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* [dpdk-dev] [PATCH v5 00/11] user space vhost library and vhost example
@ 2014-09-26  9:45 Huawei Xie
  2014-09-26  9:45 ` [dpdk-dev] [PATCH v5 01/11] lib/librte_vhost: move src files in vhost example to vhost lib directory Huawei Xie
                   ` (10 more replies)
  0 siblings, 11 replies; 23+ messages in thread
From: Huawei Xie @ 2014-09-26  9:45 UTC (permalink / raw)
  To: dev

This set of patches transforms and refactors vhost example to a user
space vhost library and a new vhost example based on this library.
This library implements a user space vhost cuse driver, and provides
generic APIs for user space ethernet vSwitch to integrate us-vhost for
fast packet switching with guest virtio.

The vhost lib consists of five APIs puls several other helper routines.
1) rte_vhost_driver_register initialises vhost driver.
2) rte_vhost_driver_callback_register registers new_device/destroy_device
callbacks. Those callbacks should be implemented in ethernet switch application.
new_device is called when a virtio_device is ready for processing.
destroy_device is called when a virtio_device is de-activated by guest.
3) rte_vhost_driver_session_start starts vhost driver
4) rte_vhost_enqueue_burst and rte_vhost_dequeue_burst for enqueue/dequeue
to/from virtio ring.

Change notes:
  v2) Turn of vhost lib by default
  v3) Fixed checkpatch issues
  v4) Split the monolithic patch
  v5) Merge merge-able rx/tx and mbuf change. Lots of coding style fixes.

Huawei Xie (11):
  1) move src files in vhost example to vhost lib directory.
  2) copy vhost rx/tx functions from main.c to a new file vhost_rxtx.c.
  3) remove main.c and main.h in vhost lib.
  4) rename virtio-net.h to rte_virtio_net.h as API header file.
  5) VMDQ, MAC learning related switching logic are removed from library.
  6) zero copy logic isn't generic enough at this stage, and is moved to example.
  7) retry logic is moved from vhost rx functions in vhost lib to switch_worker
switching function in example.
  8) add TODOs/FIXME   
    -allow application to disable cmpset reserve in rte_vhost_enqueue_burst in case
     there is no contention.      
    -fix memcpy from mbuf to vring desc when mbuf is chained and the
    desc couldn't hold all the data
    -fix vhost_set_mem_table possible race condition: two vqs concurrently   
     calls set_mem_table which cause saved mem_temp to be overided.  
  9) merge vhost merge-able rx
  10) for vhost tx, previous vhost merge-able feature introduces another version of
    virtio_dev_merge_tx, and calls virtio_dev_tx and vritio_dev_merge_tx
    respectively depends on whether the vhost device supports merge-able feature.
    Actually "merge-able" tx is the fix for memcpy from chained vring desc to mbuf.
    will use virtio_dev_merge_tx as the base for vhost tx.
  11) merge mbuf patch in vhost lib.
  12) fixes serious coding style issues.
  13) add vhost lib Makefile and vhost lib support in DPDK makefile. vhost lib is turned
off by default as it requires fuse-devel package.
  14) copy old vhost example files main.c and main.h as the base for new vhost example
  15) modify vhost example to use vhost lib API, and merge Oliver's mbuf patch.
 

 config/common_linuxapp                       |    8 +
 examples/vhost/Makefile                      |   10 +-
 examples/vhost/eventfd_link/Makefile         |   39 -
 examples/vhost/eventfd_link/eventfd_link.c   |  205 ----
 examples/vhost/eventfd_link/eventfd_link.h   |   79 --
 examples/vhost/libvirt/qemu-wrap.py          |  367 -------
 examples/vhost/main.c                        | 1465 +++++++-------------------
 examples/vhost/main.h                        |   47 +-
 examples/vhost/vhost-net-cdev.c              |  367 -------
 examples/vhost/vhost-net-cdev.h              |   83 --
 examples/vhost/virtio-net.c                  | 1165 --------------------
 examples/vhost/virtio-net.h                  |  161 ---
 lib/Makefile                                 |    1 +
 lib/librte_vhost/Makefile                    |   48 +
 lib/librte_vhost/eventfd_link/Makefile       |   39 +
 lib/librte_vhost/eventfd_link/eventfd_link.c |  205 ++++
 lib/librte_vhost/eventfd_link/eventfd_link.h |   79 ++
 lib/librte_vhost/libvirt/qemu-wrap.py        |  367 +++++++
 lib/librte_vhost/rte_virtio_net.h            |  207 ++++
 lib/librte_vhost/vhost-net-cdev.c            |  362 +++++++
 lib/librte_vhost/vhost-net-cdev.h            |  113 ++
 lib/librte_vhost/vhost_rxtx.c                |  737 +++++++++++++
 lib/librte_vhost/virtio-net.c                | 1029 ++++++++++++++++++
 mk/rte.app.mk                                |    5 +
 24 files changed, 3636 insertions(+), 3552 deletions(-)
 delete mode 100644 examples/vhost/eventfd_link/Makefile
 delete mode 100644 examples/vhost/eventfd_link/eventfd_link.c
 delete mode 100644 examples/vhost/eventfd_link/eventfd_link.h
 delete mode 100755 examples/vhost/libvirt/qemu-wrap.py
 delete mode 100644 examples/vhost/vhost-net-cdev.c
 delete mode 100644 examples/vhost/vhost-net-cdev.h
 delete mode 100644 examples/vhost/virtio-net.c
 delete mode 100644 examples/vhost/virtio-net.h
 create mode 100644 lib/librte_vhost/Makefile
 create mode 100644 lib/librte_vhost/eventfd_link/Makefile
 create mode 100644 lib/librte_vhost/eventfd_link/eventfd_link.c
 create mode 100644 lib/librte_vhost/eventfd_link/eventfd_link.h
 create mode 100755 lib/librte_vhost/libvirt/qemu-wrap.py
 create mode 100644 lib/librte_vhost/rte_virtio_net.h
 create mode 100644 lib/librte_vhost/vhost-net-cdev.c
 create mode 100644 lib/librte_vhost/vhost-net-cdev.h
 create mode 100644 lib/librte_vhost/vhost_rxtx.c
 create mode 100644 lib/librte_vhost/virtio-net.c

-- 
1.8.1.4

^ permalink raw reply	[flat|nested] 23+ messages in thread

* [dpdk-dev] [PATCH v5 01/11] lib/librte_vhost: move src files in vhost example to vhost lib directory
  2014-09-26  9:45 [dpdk-dev] [PATCH v5 00/11] user space vhost library and vhost example Huawei Xie
@ 2014-09-26  9:45 ` Huawei Xie
  2014-09-29 19:41   ` Thomas Monjalon
  2014-09-26  9:45 ` [dpdk-dev] [PATCH v5 02/11] lib/librte_vhost: refactor vhost lib for subsequent transform Huawei Xie
                   ` (9 subsequent siblings)
  10 siblings, 1 reply; 23+ messages in thread
From: Huawei Xie @ 2014-09-26  9:45 UTC (permalink / raw)
  To: dev

"git mv examples/vhost lib/librte_vhost"
This is a purely src file move, without any modification.
Subsequent patch will transform those src files to a vhost library.

Signed-off-by: Huawei Xie <huawei.xie@intel.com>
---
 examples/vhost/Makefile                      |   60 -
 examples/vhost/eventfd_link/Makefile         |   39 -
 examples/vhost/eventfd_link/eventfd_link.c   |  205 --
 examples/vhost/eventfd_link/eventfd_link.h   |   79 -
 examples/vhost/libvirt/qemu-wrap.py          |  367 ---
 examples/vhost/main.c                        | 3725 --------------------------
 examples/vhost/main.h                        |   86 -
 examples/vhost/vhost-net-cdev.c              |  367 ---
 examples/vhost/vhost-net-cdev.h              |   83 -
 examples/vhost/virtio-net.c                  | 1165 --------
 examples/vhost/virtio-net.h                  |  161 --
 lib/librte_vhost/eventfd_link/Makefile       |   39 +
 lib/librte_vhost/eventfd_link/eventfd_link.c |  205 ++
 lib/librte_vhost/eventfd_link/eventfd_link.h |   79 +
 lib/librte_vhost/libvirt/qemu-wrap.py        |  367 +++
 lib/librte_vhost/main.c                      | 3725 ++++++++++++++++++++++++++
 lib/librte_vhost/main.h                      |   86 +
 lib/librte_vhost/vhost-net-cdev.c            |  367 +++
 lib/librte_vhost/vhost-net-cdev.h            |   83 +
 lib/librte_vhost/virtio-net.c                | 1165 ++++++++
 lib/librte_vhost/virtio-net.h                |  161 ++
 21 files changed, 6277 insertions(+), 6337 deletions(-)
 delete mode 100644 examples/vhost/Makefile
 delete mode 100644 examples/vhost/eventfd_link/Makefile
 delete mode 100644 examples/vhost/eventfd_link/eventfd_link.c
 delete mode 100644 examples/vhost/eventfd_link/eventfd_link.h
 delete mode 100755 examples/vhost/libvirt/qemu-wrap.py
 delete mode 100644 examples/vhost/main.c
 delete mode 100644 examples/vhost/main.h
 delete mode 100644 examples/vhost/vhost-net-cdev.c
 delete mode 100644 examples/vhost/vhost-net-cdev.h
 delete mode 100644 examples/vhost/virtio-net.c
 delete mode 100644 examples/vhost/virtio-net.h
 create mode 100644 lib/librte_vhost/eventfd_link/Makefile
 create mode 100644 lib/librte_vhost/eventfd_link/eventfd_link.c
 create mode 100644 lib/librte_vhost/eventfd_link/eventfd_link.h
 create mode 100755 lib/librte_vhost/libvirt/qemu-wrap.py
 create mode 100644 lib/librte_vhost/main.c
 create mode 100644 lib/librte_vhost/main.h
 create mode 100644 lib/librte_vhost/vhost-net-cdev.c
 create mode 100644 lib/librte_vhost/vhost-net-cdev.h
 create mode 100644 lib/librte_vhost/virtio-net.c
 create mode 100644 lib/librte_vhost/virtio-net.h

diff --git a/examples/vhost/Makefile b/examples/vhost/Makefile
deleted file mode 100644
index f45f83f..0000000
--- a/examples/vhost/Makefile
+++ /dev/null
@@ -1,60 +0,0 @@
-#   BSD LICENSE
-#
-#   Copyright(c) 2010-2014 Intel Corporation. All rights reserved.
-#   All rights reserved.
-#
-#   Redistribution and use in source and binary forms, with or without
-#   modification, are permitted provided that the following conditions
-#   are met:
-#
-#     * Redistributions of source code must retain the above copyright
-#       notice, this list of conditions and the following disclaimer.
-#     * Redistributions in binary form must reproduce the above copyright
-#       notice, this list of conditions and the following disclaimer in
-#       the documentation and/or other materials provided with the
-#       distribution.
-#     * Neither the name of Intel Corporation nor the names of its
-#       contributors may be used to endorse or promote products derived
-#       from this software without specific prior written permission.
-#
-#   THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
-#   "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
-#   LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
-#   A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
-#   OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
-#   SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
-#   LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
-#   DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
-#   THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
-#   (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
-#   OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
-
-ifeq ($(RTE_SDK),)
-$(error "Please define RTE_SDK environment variable")
-endif
-
-# Default target, can be overriden by command line or environment
-RTE_TARGET ?= x86_64-native-linuxapp-gcc
-
-include $(RTE_SDK)/mk/rte.vars.mk
-
-ifneq ($(CONFIG_RTE_EXEC_ENV),"linuxapp")
-$(info This application can only operate in a linuxapp environment, \
-please change the definition of the RTE_TARGET environment variable)
-all:
-else
-
-# binary name
-APP = vhost-switch
-
-# all source are stored in SRCS-y
-#SRCS-y := cusedrv.c loopback-userspace.c
-SRCS-y := main.c virtio-net.c vhost-net-cdev.c
-
-CFLAGS += -O2 -I/usr/local/include -D_FILE_OFFSET_BITS=64 -Wno-unused-parameter
-CFLAGS += $(WERROR_FLAGS)
-LDFLAGS += -lfuse
-
-include $(RTE_SDK)/mk/rte.extapp.mk
-
-endif
diff --git a/examples/vhost/eventfd_link/Makefile b/examples/vhost/eventfd_link/Makefile
deleted file mode 100644
index fc3927b..0000000
--- a/examples/vhost/eventfd_link/Makefile
+++ /dev/null
@@ -1,39 +0,0 @@
-#   BSD LICENSE
-#
-#   Copyright(c) 2010-2014 Intel Corporation. All rights reserved.
-#   All rights reserved.
-#
-#   Redistribution and use in source and binary forms, with or without
-#   modification, are permitted provided that the following conditions
-#   are met:
-#
-#     * Redistributions of source code must retain the above copyright
-#       notice, this list of conditions and the following disclaimer.
-#     * Redistributions in binary form must reproduce the above copyright
-#       notice, this list of conditions and the following disclaimer in
-#       the documentation and/or other materials provided with the
-#       distribution.
-#     * Neither the name of Intel Corporation nor the names of its
-#       contributors may be used to endorse or promote products derived
-#       from this software without specific prior written permission.
-#
-#   THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
-#   "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
-#   LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
-#   A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
-#   OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
-#   SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
-#   LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
-#   DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
-#   THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
-#   (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
-#   OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
-
-obj-m += eventfd_link.o
-
-
-all:
-	make -C /lib/modules/$(shell uname -r)/build M=$(PWD) modules
-
-clean:
-	make -C /lib/modules/$(shell uname -r)/build M=$(PWD) clean
diff --git a/examples/vhost/eventfd_link/eventfd_link.c b/examples/vhost/eventfd_link/eventfd_link.c
deleted file mode 100644
index fc0653a..0000000
--- a/examples/vhost/eventfd_link/eventfd_link.c
+++ /dev/null
@@ -1,205 +0,0 @@
-/*-
- *  * GPL LICENSE SUMMARY
- *  *
- *  *   Copyright(c) 2010-2014 Intel Corporation. All rights reserved.
- *  *
- *  *   This program is free software; you can redistribute it and/or modify
- *  *   it under the terms of version 2 of the GNU General Public License as
- *  *   published by the Free Software Foundation.
- *  *
- *  *   This program is distributed in the hope that it will be useful, but
- *  *   WITHOUT ANY WARRANTY; without even the implied warranty of
- *  *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
- *  *   General Public License for more details.
- *  *
- *  *   You should have received a copy of the GNU General Public License
- *  *   along with this program; if not, write to the Free Software
- *  *   Foundation, Inc., 51 Franklin St - Fifth Floor, Boston, MA 02110-1301 USA.
- *  *   The full GNU General Public License is included in this distribution
- *  *   in the file called LICENSE.GPL.
- *  *
- *  *   Contact Information:
- *  *   Intel Corporation
- *   */
-
-#include <linux/eventfd.h>
-#include <linux/miscdevice.h>
-#include <linux/module.h>
-#include <linux/moduleparam.h>
-#include <linux/rcupdate.h>
-#include <linux/file.h>
-#include <linux/slab.h>
-#include <linux/fs.h>
-#include <linux/mmu_context.h>
-#include <linux/sched.h>
-#include <asm/mmu_context.h>
-#include <linux/fdtable.h>
-
-#include "eventfd_link.h"
-
-
-/*
- * get_files_struct is copied from fs/file.c
- */
-struct files_struct *
-get_files_struct (struct task_struct *task)
-{
-	struct files_struct *files;
-
-	task_lock (task);
-	files = task->files;
-	if (files)
-		atomic_inc (&files->count);
-	task_unlock (task);
-
-	return files;
-}
-
-/*
- * put_files_struct is extracted from fs/file.c
- */
-void
-put_files_struct (struct files_struct *files)
-{
-	if (atomic_dec_and_test (&files->count))
-	{
-		BUG ();
-	}
-}
-
-
-static long
-eventfd_link_ioctl (struct file *f, unsigned int ioctl, unsigned long arg)
-{
-	void __user *argp = (void __user *) arg;
-	struct task_struct *task_target = NULL;
-	struct file *file;
-	struct files_struct *files;
-	struct fdtable *fdt;
-	struct eventfd_copy eventfd_copy;
-
-	switch (ioctl)
-	{
-		case EVENTFD_COPY:
-			if (copy_from_user (&eventfd_copy, argp, sizeof (struct eventfd_copy)))
-				return -EFAULT;
-
-			/*
-			 * Find the task struct for the target pid
-			 */
-			task_target =
-				pid_task (find_vpid (eventfd_copy.target_pid), PIDTYPE_PID);
-			if (task_target == NULL)
-			{
-				printk (KERN_DEBUG "Failed to get mem ctx for target pid\n");
-				return -EFAULT;
-			}
-
-			files = get_files_struct (current);
-			if (files == NULL)
-			{
-				printk (KERN_DEBUG "Failed to get files struct\n");
-				return -EFAULT;
-			}
-
-			rcu_read_lock ();
-			file = fcheck_files (files, eventfd_copy.source_fd);
-			if (file)
-			{
-				if (file->f_mode & FMODE_PATH
-						|| !atomic_long_inc_not_zero (&file->f_count))
-					file = NULL;
-			}
-			rcu_read_unlock ();
-			put_files_struct (files);
-
-			if (file == NULL)
-			{
-				printk (KERN_DEBUG "Failed to get file from source pid\n");
-				return 0;
-			}
-
-			/*
-			 * Release the existing eventfd in the source process
-			 */
-			spin_lock (&files->file_lock);
-			filp_close (file, files);
-			fdt = files_fdtable (files);
-			fdt->fd[eventfd_copy.source_fd] = NULL;
-			spin_unlock (&files->file_lock);
-
-			/*
-			 * Find the file struct associated with the target fd.
-			 */
-
-			files = get_files_struct (task_target);
-			if (files == NULL)
-			{
-				printk (KERN_DEBUG "Failed to get files struct\n");
-				return -EFAULT;
-			}
-
-			rcu_read_lock ();
-			file = fcheck_files (files, eventfd_copy.target_fd);
-			if (file)
-			{
-				if (file->f_mode & FMODE_PATH
-						|| !atomic_long_inc_not_zero (&file->f_count))
-					file = NULL;
-			}
-			rcu_read_unlock ();
-			put_files_struct (files);
-
-			if (file == NULL)
-			{
-				printk (KERN_DEBUG "Failed to get file from target pid\n");
-				return 0;
-			}
-
-
-			/*
-			 * Install the file struct from the target process into the
-			 * file desciptor of the source process,
-			 */
-
-			fd_install (eventfd_copy.source_fd, file);
-
-			return 0;
-
-		default:
-			return -ENOIOCTLCMD;
-	}
-}
-
-static const struct file_operations eventfd_link_fops = {
-	.owner = THIS_MODULE,
-	.unlocked_ioctl = eventfd_link_ioctl,
-};
-
-
-static struct miscdevice eventfd_link_misc = {
-	.name = "eventfd-link",
-	.fops = &eventfd_link_fops,
-};
-
-static int __init
-eventfd_link_init (void)
-{
-	return misc_register (&eventfd_link_misc);
-}
-
-module_init (eventfd_link_init);
-
-static void __exit
-eventfd_link_exit (void)
-{
-	misc_deregister (&eventfd_link_misc);
-}
-
-module_exit (eventfd_link_exit);
-
-MODULE_VERSION ("0.0.1");
-MODULE_LICENSE ("GPL v2");
-MODULE_AUTHOR ("Anthony Fee");
-MODULE_DESCRIPTION ("Link eventfd");
-MODULE_ALIAS ("devname:eventfd-link");
diff --git a/examples/vhost/eventfd_link/eventfd_link.h b/examples/vhost/eventfd_link/eventfd_link.h
deleted file mode 100644
index a32a8dd..0000000
--- a/examples/vhost/eventfd_link/eventfd_link.h
+++ /dev/null
@@ -1,79 +0,0 @@
-/*-
- *  * This file is provided under a dual BSD/GPLv2 license.  When using or
- *  *   redistributing this file, you may do so under either license.
- *  *
- *  *   GPL LICENSE SUMMARY
- *  *
- *  *   Copyright(c) 2010-2014 Intel Corporation. All rights reserved.
- *  *
- *  *   This program is free software; you can redistribute it and/or modify
- *  *   it under the terms of version 2 of the GNU General Public License as
- *  *   published by the Free Software Foundation.
- *  *
- *  *   This program is distributed in the hope that it will be useful, but
- *  *   WITHOUT ANY WARRANTY; without even the implied warranty of
- *  *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
- *  *   General Public License for more details.
- *  *
- *  *   You should have received a copy of the GNU General Public License
- *  *   along with this program; if not, write to the Free Software
- *  *   Foundation, Inc., 51 Franklin St - Fifth Floor, Boston, MA 02110-1301 USA.
- *  *   The full GNU General Public License is included in this distribution
- *  *   in the file called LICENSE.GPL.
- *  *
- *  *   Contact Information:
- *  *   Intel Corporation
- *  *
- *  *   BSD LICENSE
- *  *
- *  *   Copyright(c) 2010-2014 Intel Corporation. All rights reserved.
- *  *   All rights reserved.
- *  *
- *  *   Redistribution and use in source and binary forms, with or without
- *  *   modification, are permitted provided that the following conditions
- *  *   are met:
- *  *
- *  *     * Redistributions of source code must retain the above copyright
- *  *       notice, this list of conditions and the following disclaimer.
- *  *     * Redistributions in binary form must reproduce the above copyright
- *  *       notice, this list of conditions and the following disclaimer in
- *  *       the documentation and/or other materials provided with the
- *  *       distribution.
- *  *     * Neither the name of Intel Corporation nor the names of its
- *  *       contributors may be used to endorse or promote products derived
- *  *       from this software without specific prior written permission.
- *  *
- *  *   THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- *  *   "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- *  *   LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- *  *   A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- *  *   OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- *  *   SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- *  *   LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- *  *   DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- *  *   THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- *  *   (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- *  *   OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
- *  *
- *   */
-
-#ifndef _EVENTFD_LINK_H_
-#define _EVENTFD_LINK_H_
-
-/*
- *	ioctl to copy an fd entry in calling process to an fd in a target process
- */
-#define EVENTFD_COPY 1
-
-/*
- *	arguements for the EVENTFD_COPY ioctl
- */
-struct eventfd_copy {
-	// fd in the target pid
-    unsigned target_fd;
-	// fd in the calling pid
-    unsigned source_fd;
-	// pid of the target pid
-    pid_t target_pid;
-};
-#endif /* _EVENTFD_LINK_H_ */
diff --git a/examples/vhost/libvirt/qemu-wrap.py b/examples/vhost/libvirt/qemu-wrap.py
deleted file mode 100755
index e2d68a0..0000000
--- a/examples/vhost/libvirt/qemu-wrap.py
+++ /dev/null
@@ -1,367 +0,0 @@
-#!/usr/bin/python
-#/*
-# *   BSD LICENSE
-# *
-# *   Copyright(c) 2010-2014 Intel Corporation. All rights reserved.
-# *   All rights reserved.
-# *
-# *   Redistribution and use in source and binary forms, with or without
-# *   modification, are permitted provided that the following conditions
-# *   are met:
-# *
-# *     * Redistributions of source code must retain the above copyright
-# *       notice, this list of conditions and the following disclaimer.
-# *     * Redistributions in binary form must reproduce the above copyright
-# *       notice, this list of conditions and the following disclaimer in
-# *       the documentation and/or other materials provided with the
-# *       distribution.
-# *     * Neither the name of Intel Corporation nor the names of its
-# *       contributors may be used to endorse or promote products derived
-# *       from this software without specific prior written permission.
-# *
-# *   THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
-# *   "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
-# *   LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
-# *   A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
-# *   OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
-# *   SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
-# *   LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
-# *   DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
-# *   THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
-# *   (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
-# *   OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
-# */
-
-#####################################################################
-# This script is designed to modify the call to the QEMU emulator
-# to support userspace vhost when starting a guest machine through
-# libvirt with vhost enabled. The steps to enable this are as follows
-# and should be run as root:
-#
-# 1. Place this script in a libvirtd's binary search PATH ($PATH)
-#    A good location would be in the same directory that the QEMU
-#    binary is located
-#
-# 2. Ensure that the script has the same owner/group and file
-#    permissions as the QEMU binary
-#
-# 3. Update the VM xml file using "virsh edit VM.xml"
-#
-#    3.a) Set the VM to use the launch script
-#
-#    	Set the emulator path contained in the
-#		<emulator><emulator/> tags
-#
-#    	e.g replace <emulator>/usr/bin/qemu-kvm<emulator/>
-#        with    <emulator>/usr/bin/qemu-wrap.py<emulator/>
-#
-#	 3.b) Set the VM's device's to use vhost-net offload
-#
-#		<interface type="network">
-#       	<model type="virtio"/>
-#       	<driver name="vhost"/>
-#		<interface/>
-#
-# 4. Enable libvirt to access our userpace device file by adding it to
-#    controllers cgroup for libvirtd using the following steps
-#
-#   4.a) In /etc/libvirt/qemu.conf add/edit the following lines:
-#         1) cgroup_controllers = [ ... "devices", ... ]
-#		  2) clear_emulator_capabilities = 0
-#         3) user = "root"
-#         4) group = "root"
-#         5) cgroup_device_acl = [
-#                "/dev/null", "/dev/full", "/dev/zero",
-#                "/dev/random", "/dev/urandom",
-#                "/dev/ptmx", "/dev/kvm", "/dev/kqemu",
-#                "/dev/rtc", "/dev/hpet", "/dev/net/tun",
-#                "/dev/<devbase-name>-<index>",
-#            ]
-#
-#   4.b) Disable SELinux or set to permissive mode
-#
-#   4.c) Mount cgroup device controller
-#        "mkdir /dev/cgroup"
-#        "mount -t cgroup none /dev/cgroup -o devices"
-#
-#   4.d) Set hugetlbfs_mount variable - ( Optional )
-#        VMs using userspace vhost must use hugepage backed
-#        memory. This can be enabled in the libvirt XML
-#        config by adding a memory backing section to the
-#        XML config e.g.
-#             <memoryBacking>
-#             <hugepages/>
-#             </memoryBacking>
-#        This memory backing section should be added after the
-#        <memory> and <currentMemory> sections. This will add
-#        flags "-mem-prealloc -mem-path <path>" to the QEMU
-#        command line. The hugetlbfs_mount variable can be used
-#        to override the default <path> passed through by libvirt.
-#
-#        if "-mem-prealloc" or "-mem-path <path>" are not passed
-#        through and a vhost device is detected then these options will
-#        be automatically added by this script. This script will detect
-#        the system hugetlbfs mount point to be used for <path>. The
-#        default <path> for this script can be overidden by the
-#        hugetlbfs_dir variable in the configuration section of this script.
-#
-#
-#   4.e) Restart the libvirtd system process
-#        e.g. on Fedora "systemctl restart libvirtd.service"
-#
-#
-#   4.f) Edit the Configuration Parameters section of this script
-#        to point to the correct emulator location and set any
-#        addition options
-#
-# The script modifies the libvirtd Qemu call by modifying/adding
-# options based on the configuration parameters below.
-# NOTE:
-#     emul_path and us_vhost_path must be set
-#     All other parameters are optional
-#####################################################################
-
-
-#############################################
-# Configuration Parameters
-#############################################
-#Path to QEMU binary
-emul_path = "/usr/local/bin/qemu-system-x86_64"
-
-#Path to userspace vhost device file
-# This filename should match the --dev-basename --dev-index parameters of
-# the command used to launch the userspace vhost sample application e.g.
-# if the sample app lauch command is:
-#    ./build/vhost-switch ..... --dev-basename usvhost --dev-index 1
-# then this variable should be set to:
-#   us_vhost_path = "/dev/usvhost-1"
-us_vhost_path = "/dev/usvhost-1"
-
-#List of additional user defined emulation options. These options will
-#be added to all Qemu calls
-emul_opts_user = []
-
-#List of additional user defined emulation options for vhost only.
-#These options will only be added to vhost enabled guests
-emul_opts_user_vhost = []
-
-#For all VHOST enabled VMs, the VM memory is preallocated from hugetlbfs
-# Set this variable to one to enable this option for all VMs
-use_huge_all = 0
-
-#Instead of autodetecting, override the hugetlbfs directory by setting
-#this variable
-hugetlbfs_dir = ""
-
-#############################################
-
-
-#############################################
-# ****** Do Not Modify Below this Line ******
-#############################################
-
-import sys, os, subprocess
-
-
-#List of open userspace vhost file descriptors
-fd_list = []
-
-#additional virtio device flags when using userspace vhost
-vhost_flags = [ "csum=off",
-                "gso=off",
-                "guest_tso4=off",
-                "guest_tso6=off",
-                "guest_ecn=off"
-              ]
-
-
-#############################################
-# Find the system hugefile mount point.
-# Note:
-# if multiple hugetlbfs mount points exist
-# then the first one found will be used
-#############################################
-def find_huge_mount():
-
-    if (len(hugetlbfs_dir)):
-        return hugetlbfs_dir
-
-    huge_mount = ""
-
-    if (os.access("/proc/mounts", os.F_OK)):
-        f = open("/proc/mounts", "r")
-        line = f.readline()
-        while line:
-            line_split = line.split(" ")
-            if line_split[2] == 'hugetlbfs':
-                huge_mount = line_split[1]
-                break
-            line = f.readline()
-    else:
-        print "/proc/mounts not found"
-        exit (1)
-
-    f.close
-    if len(huge_mount) == 0:
-        print "Failed to find hugetlbfs mount point"
-        exit (1)
-
-    return huge_mount
-
-
-#############################################
-# Get a userspace Vhost file descriptor
-#############################################
-def get_vhost_fd():
-
-    if (os.access(us_vhost_path, os.F_OK)):
-        fd = os.open( us_vhost_path, os.O_RDWR)
-    else:
-        print ("US-Vhost file %s not found" %us_vhost_path)
-        exit (1)
-
-    return fd
-
-
-#############################################
-# Check for vhostfd. if found then replace
-# with our own vhost fd and append any vhost
-# flags onto the end
-#############################################
-def modify_netdev_arg(arg):
-	
-    global fd_list
-    vhost_in_use = 0
-    s = ''
-    new_opts = []
-    netdev_opts = arg.split(",")
-
-    for opt in netdev_opts:
-        #check if vhost is used
-        if "vhost" == opt[:5]:
-            vhost_in_use = 1
-        else:
-            new_opts.append(opt)
-
-    #if using vhost append vhost options
-    if vhost_in_use == 1:
-        #append vhost on option
-        new_opts.append('vhost=on')
-        #append vhostfd ption
-        new_fd = get_vhost_fd()
-        new_opts.append('vhostfd=' + str(new_fd))
-        fd_list.append(new_fd)
-
-    #concatenate all options
-    for opt in new_opts:
-        if len(s) > 0:
-			s+=','
-
-        s+=opt
-
-    return s	
-
-
-#############################################
-# Main
-#############################################
-def main():
-
-    global fd_list
-    global vhost_in_use
-    new_args = []
-    num_cmd_args = len(sys.argv)
-    emul_call = ''
-    mem_prealloc_set = 0
-    mem_path_set = 0
-    num = 0;
-
-    #parse the parameters
-    while (num < num_cmd_args):
-        arg = sys.argv[num]
-
-		#Check netdev +1 parameter for vhostfd
-        if arg == '-netdev':
-            num_vhost_devs = len(fd_list)
-            new_args.append(arg)
-
-            num+=1
-            arg = sys.argv[num]
-            mod_arg = modify_netdev_arg(arg)
-            new_args.append(mod_arg)
-
-            #append vhost flags if this is a vhost device
-            # and -device is the next arg
-            # i.e -device -opt1,-opt2,...,-opt3,%vhost
-            if (num_vhost_devs < len(fd_list)):
-                num+=1
-                arg = sys.argv[num]
-                if arg == '-device':
-                    new_args.append(arg)
-                    num+=1
-                    new_arg = sys.argv[num]
-                    for flag in vhost_flags:
-                        new_arg = ''.join([new_arg,',',flag])
-                    new_args.append(new_arg)
-                else:
-                    new_args.append(arg)
-        elif arg == '-mem-prealloc':
-            mem_prealloc_set = 1
-            new_args.append(arg)
-        elif arg == '-mem-path':
-            mem_path_set = 1
-            new_args.append(arg)
-
-        else:
-            new_args.append(arg)
-
-        num+=1
-
-    #Set Qemu binary location
-    emul_call+=emul_path
-    emul_call+=" "
-
-    #Add prealloc mem options if using vhost and not already added
-    if ((len(fd_list) > 0) and (mem_prealloc_set == 0)):
-        emul_call += "-mem-prealloc "
-
-    #Add mempath mem options if using vhost and not already added
-    if ((len(fd_list) > 0) and (mem_path_set == 0)):
-        #Detect and add hugetlbfs mount point
-        mp = find_huge_mount()
-        mp = "".join(["-mem-path ", mp])
-        emul_call += mp
-        emul_call += " "
-
-
-    #add user options
-    for opt in emul_opts_user:
-        emul_call += opt
-        emul_call += " "
-
-    #Add add user vhost only options
-    if len(fd_list) > 0:
-        for opt in emul_opts_user_vhost:
-            emul_call += opt
-            emul_call += " "
-
-    #Add updated libvirt options
-    iter_args = iter(new_args)
-    #skip 1st arg i.e. call to this script
-    next(iter_args)
-    for arg in iter_args:
-        emul_call+=str(arg)
-        emul_call+= " "
-
-    #Call QEMU
-    subprocess.call(emul_call, shell=True)
-
-
-    #Close usvhost files
-    for fd in fd_list:
-        os.close(fd)
-
-
-if __name__ == "__main__":
-    main()
-
diff --git a/examples/vhost/main.c b/examples/vhost/main.c
deleted file mode 100644
index 85ee8b8..0000000
--- a/examples/vhost/main.c
+++ /dev/null
@@ -1,3725 +0,0 @@
-/*-
- *   BSD LICENSE
- *
- *   Copyright(c) 2010-2014 Intel Corporation. All rights reserved.
- *   All rights reserved.
- *
- *   Redistribution and use in source and binary forms, with or without
- *   modification, are permitted provided that the following conditions
- *   are met:
- *
- *     * Redistributions of source code must retain the above copyright
- *       notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above copyright
- *       notice, this list of conditions and the following disclaimer in
- *       the documentation and/or other materials provided with the
- *       distribution.
- *     * Neither the name of Intel Corporation nor the names of its
- *       contributors may be used to endorse or promote products derived
- *       from this software without specific prior written permission.
- *
- *   THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- *   "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- *   LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- *   A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- *   OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- *   SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- *   LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- *   DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- *   THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- *   (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- *   OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
- */
-
-#include <arpa/inet.h>
-#include <getopt.h>
-#include <linux/if_ether.h>
-#include <linux/if_vlan.h>
-#include <linux/virtio_net.h>
-#include <linux/virtio_ring.h>
-#include <signal.h>
-#include <stdint.h>
-#include <sys/eventfd.h>
-#include <sys/param.h>
-#include <unistd.h>
-
-#include <rte_atomic.h>
-#include <rte_cycles.h>
-#include <rte_ethdev.h>
-#include <rte_log.h>
-#include <rte_string_fns.h>
-#include <rte_malloc.h>
-
-#include "main.h"
-#include "virtio-net.h"
-#include "vhost-net-cdev.h"
-
-#define MAX_QUEUES 128
-
-/* the maximum number of external ports supported */
-#define MAX_SUP_PORTS 1
-
-/*
- * Calculate the number of buffers needed per port
- */
-#define NUM_MBUFS_PER_PORT ((MAX_QUEUES*RTE_TEST_RX_DESC_DEFAULT) +  		\
-							(num_switching_cores*MAX_PKT_BURST) +  			\
-							(num_switching_cores*RTE_TEST_TX_DESC_DEFAULT) +\
-							(num_switching_cores*MBUF_CACHE_SIZE))
-
-#define MBUF_CACHE_SIZE 128
-#define MBUF_SIZE (2048 + sizeof(struct rte_mbuf) + RTE_PKTMBUF_HEADROOM)
-
-/*
- * No frame data buffer allocated from host are required for zero copy
- * implementation, guest will allocate the frame data buffer, and vhost
- * directly use it.
- */
-#define VIRTIO_DESCRIPTOR_LEN_ZCP 1518
-#define MBUF_SIZE_ZCP (VIRTIO_DESCRIPTOR_LEN_ZCP + sizeof(struct rte_mbuf) \
-	+ RTE_PKTMBUF_HEADROOM)
-#define MBUF_CACHE_SIZE_ZCP 0
-
-/*
- * RX and TX Prefetch, Host, and Write-back threshold values should be
- * carefully set for optimal performance. Consult the network
- * controller's datasheet and supporting DPDK documentation for guidance
- * on how these parameters should be set.
- */
-#define RX_PTHRESH 8 /* Default values of RX prefetch threshold reg. */
-#define RX_HTHRESH 8 /* Default values of RX host threshold reg. */
-#define RX_WTHRESH 4 /* Default values of RX write-back threshold reg. */
-
-/*
- * These default values are optimized for use with the Intel(R) 82599 10 GbE
- * Controller and the DPDK ixgbe PMD. Consider using other values for other
- * network controllers and/or network drivers.
- */
-#define TX_PTHRESH 36 /* Default values of TX prefetch threshold reg. */
-#define TX_HTHRESH 0  /* Default values of TX host threshold reg. */
-#define TX_WTHRESH 0  /* Default values of TX write-back threshold reg. */
-
-#define MAX_PKT_BURST 32 		/* Max burst size for RX/TX */
-#define MAX_MRG_PKT_BURST 16 	/* Max burst for merge buffers. Set to 1 due to performance issue. */
-#define BURST_TX_DRAIN_US 100 	/* TX drain every ~100us */
-
-#define BURST_RX_WAIT_US 15 	/* Defines how long we wait between retries on RX */
-#define BURST_RX_RETRIES 4		/* Number of retries on RX. */
-
-#define JUMBO_FRAME_MAX_SIZE    0x2600
-
-/* State of virtio device. */
-#define DEVICE_MAC_LEARNING 0
-#define DEVICE_RX			1
-#define DEVICE_SAFE_REMOVE	2
-
-/* Config_core_flag status definitions. */
-#define REQUEST_DEV_REMOVAL 1
-#define ACK_DEV_REMOVAL 0
-
-/* Configurable number of RX/TX ring descriptors */
-#define RTE_TEST_RX_DESC_DEFAULT 1024
-#define RTE_TEST_TX_DESC_DEFAULT 512
-
-/*
- * Need refine these 2 macros for legacy and DPDK based front end:
- * Max vring avail descriptor/entries from guest - MAX_PKT_BURST
- * And then adjust power 2.
- */
-/*
- * For legacy front end, 128 descriptors,
- * half for virtio header, another half for mbuf.
- */
-#define RTE_TEST_RX_DESC_DEFAULT_ZCP 32   /* legacy: 32, DPDK virt FE: 128. */
-#define RTE_TEST_TX_DESC_DEFAULT_ZCP 64   /* legacy: 64, DPDK virt FE: 64.  */
-
-/* Get first 4 bytes in mbuf headroom. */
-#define MBUF_HEADROOM_UINT32(mbuf) (*(uint32_t *)((uint8_t *)(mbuf) \
-		+ sizeof(struct rte_mbuf)))
-
-/* true if x is a power of 2 */
-#define POWEROF2(x) ((((x)-1) & (x)) == 0)
-
-#define INVALID_PORT_ID 0xFF
-
-/* Max number of devices. Limited by vmdq. */
-#define MAX_DEVICES 64
-
-/* Size of buffers used for snprintfs. */
-#define MAX_PRINT_BUFF 6072
-
-/* Maximum character device basename size. */
-#define MAX_BASENAME_SZ 10
-
-/* Maximum long option length for option parsing. */
-#define MAX_LONG_OPT_SZ 64
-
-/* Used to compare MAC addresses. */
-#define MAC_ADDR_CMP 0xFFFFFFFFFFFFULL
-
-/* Number of descriptors per cacheline. */
-#define DESC_PER_CACHELINE (CACHE_LINE_SIZE / sizeof(struct vring_desc))
-
-/* mask of enabled ports */
-static uint32_t enabled_port_mask = 0;
-
-/*Number of switching cores enabled*/
-static uint32_t num_switching_cores = 0;
-
-/* number of devices/queues to support*/
-static uint32_t num_queues = 0;
-uint32_t num_devices = 0;
-
-/*
- * Enable zero copy, pkts buffer will directly dma to hw descriptor,
- * disabled on default.
- */
-static uint32_t zero_copy;
-
-/* number of descriptors to apply*/
-static uint32_t num_rx_descriptor = RTE_TEST_RX_DESC_DEFAULT_ZCP;
-static uint32_t num_tx_descriptor = RTE_TEST_TX_DESC_DEFAULT_ZCP;
-
-/* max ring descriptor, ixgbe, i40e, e1000 all are 4096. */
-#define MAX_RING_DESC 4096
-
-struct vpool {
-	struct rte_mempool *pool;
-	struct rte_ring *ring;
-	uint32_t buf_size;
-} vpool_array[MAX_QUEUES+MAX_QUEUES];
-
-/* Enable VM2VM communications. If this is disabled then the MAC address compare is skipped. */
-typedef enum {
-	VM2VM_DISABLED = 0,
-	VM2VM_SOFTWARE = 1,
-	VM2VM_HARDWARE = 2,
-	VM2VM_LAST
-} vm2vm_type;
-static vm2vm_type vm2vm_mode = VM2VM_SOFTWARE;
-
-/* The type of host physical address translated from guest physical address. */
-typedef enum {
-	PHYS_ADDR_CONTINUOUS = 0,
-	PHYS_ADDR_CROSS_SUBREG = 1,
-	PHYS_ADDR_INVALID = 2,
-	PHYS_ADDR_LAST
-} hpa_type;
-
-/* Enable stats. */
-static uint32_t enable_stats = 0;
-/* Enable retries on RX. */
-static uint32_t enable_retry = 1;
-/* Specify timeout (in useconds) between retries on RX. */
-static uint32_t burst_rx_delay_time = BURST_RX_WAIT_US;
-/* Specify the number of retries on RX. */
-static uint32_t burst_rx_retry_num = BURST_RX_RETRIES;
-
-/* Character device basename. Can be set by user. */
-static char dev_basename[MAX_BASENAME_SZ] = "vhost-net";
-
-/* Charater device index. Can be set by user. */
-static uint32_t dev_index = 0;
-
-/* This can be set by the user so it is made available here. */
-extern uint64_t VHOST_FEATURES;
-
-/* Default configuration for rx and tx thresholds etc. */
-static struct rte_eth_rxconf rx_conf_default = {
-	.rx_thresh = {
-		.pthresh = RX_PTHRESH,
-		.hthresh = RX_HTHRESH,
-		.wthresh = RX_WTHRESH,
-	},
-	.rx_drop_en = 1,
-};
-
-/*
- * These default values are optimized for use with the Intel(R) 82599 10 GbE
- * Controller and the DPDK ixgbe/igb PMD. Consider using other values for other
- * network controllers and/or network drivers.
- */
-static struct rte_eth_txconf tx_conf_default = {
-	.tx_thresh = {
-		.pthresh = TX_PTHRESH,
-		.hthresh = TX_HTHRESH,
-		.wthresh = TX_WTHRESH,
-	},
-	.tx_free_thresh = 0, /* Use PMD default values */
-	.tx_rs_thresh = 0, /* Use PMD default values */
-};
-
-/* empty vmdq configuration structure. Filled in programatically */
-static struct rte_eth_conf vmdq_conf_default = {
-	.rxmode = {
-		.mq_mode        = ETH_MQ_RX_VMDQ_ONLY,
-		.split_hdr_size = 0,
-		.header_split   = 0, /**< Header Split disabled */
-		.hw_ip_checksum = 0, /**< IP checksum offload disabled */
-		.hw_vlan_filter = 0, /**< VLAN filtering disabled */
-		/*
-		 * It is necessary for 1G NIC such as I350,
-		 * this fixes bug of ipv4 forwarding in guest can't
-		 * forward pakets from one virtio dev to another virtio dev.
-		 */
-		.hw_vlan_strip  = 1, /**< VLAN strip enabled. */
-		.jumbo_frame    = 0, /**< Jumbo Frame Support disabled */
-		.hw_strip_crc   = 0, /**< CRC stripped by hardware */
-	},
-
-	.txmode = {
-		.mq_mode = ETH_MQ_TX_NONE,
-	},
-	.rx_adv_conf = {
-		/*
-		 * should be overridden separately in code with
-		 * appropriate values
-		 */
-		.vmdq_rx_conf = {
-			.nb_queue_pools = ETH_8_POOLS,
-			.enable_default_pool = 0,
-			.default_pool = 0,
-			.nb_pool_maps = 0,
-			.pool_map = {{0, 0},},
-		},
-	},
-};
-
-static unsigned lcore_ids[RTE_MAX_LCORE];
-static uint8_t ports[RTE_MAX_ETHPORTS];
-static unsigned num_ports = 0; /**< The number of ports specified in command line */
-
-static const uint16_t external_pkt_default_vlan_tag = 2000;
-const uint16_t vlan_tags[] = {
-	1000, 1001, 1002, 1003, 1004, 1005, 1006, 1007,
-	1008, 1009, 1010, 1011,	1012, 1013, 1014, 1015,
-	1016, 1017, 1018, 1019, 1020, 1021, 1022, 1023,
-	1024, 1025, 1026, 1027, 1028, 1029, 1030, 1031,
-	1032, 1033, 1034, 1035, 1036, 1037, 1038, 1039,
-	1040, 1041, 1042, 1043, 1044, 1045, 1046, 1047,
-	1048, 1049, 1050, 1051, 1052, 1053, 1054, 1055,
-	1056, 1057, 1058, 1059, 1060, 1061, 1062, 1063,
-};
-
-/* ethernet addresses of ports */
-static struct ether_addr vmdq_ports_eth_addr[RTE_MAX_ETHPORTS];
-
-/* heads for the main used and free linked lists for the data path. */
-static struct virtio_net_data_ll *ll_root_used = NULL;
-static struct virtio_net_data_ll *ll_root_free = NULL;
-
-/* Array of data core structures containing information on individual core linked lists. */
-static struct lcore_info lcore_info[RTE_MAX_LCORE];
-
-/* Used for queueing bursts of TX packets. */
-struct mbuf_table {
-	unsigned len;
-	unsigned txq_id;
-	struct rte_mbuf *m_table[MAX_PKT_BURST];
-};
-
-/* TX queue for each data core. */
-struct mbuf_table lcore_tx_queue[RTE_MAX_LCORE];
-
-/* TX queue fori each virtio device for zero copy. */
-struct mbuf_table tx_queue_zcp[MAX_QUEUES];
-
-/* Vlan header struct used to insert vlan tags on TX. */
-struct vlan_ethhdr {
-	unsigned char   h_dest[ETH_ALEN];
-	unsigned char   h_source[ETH_ALEN];
-	__be16          h_vlan_proto;
-	__be16          h_vlan_TCI;
-	__be16          h_vlan_encapsulated_proto;
-};
-
-/* IPv4 Header */
-struct ipv4_hdr {
-	uint8_t  version_ihl;		/**< version and header length */
-	uint8_t  type_of_service;	/**< type of service */
-	uint16_t total_length;		/**< length of packet */
-	uint16_t packet_id;		/**< packet ID */
-	uint16_t fragment_offset;	/**< fragmentation offset */
-	uint8_t  time_to_live;		/**< time to live */
-	uint8_t  next_proto_id;		/**< protocol ID */
-	uint16_t hdr_checksum;		/**< header checksum */
-	uint32_t src_addr;		/**< source address */
-	uint32_t dst_addr;		/**< destination address */
-} __attribute__((__packed__));
-
-/* Header lengths. */
-#define VLAN_HLEN       4
-#define VLAN_ETH_HLEN   18
-
-/* Per-device statistics struct */
-struct device_statistics {
-	uint64_t tx_total;
-	rte_atomic64_t rx_total_atomic;
-	uint64_t rx_total;
-	uint64_t tx;
-	rte_atomic64_t rx_atomic;
-	uint64_t rx;
-} __rte_cache_aligned;
-struct device_statistics dev_statistics[MAX_DEVICES];
-
-/*
- * Builds up the correct configuration for VMDQ VLAN pool map
- * according to the pool & queue limits.
- */
-static inline int
-get_eth_conf(struct rte_eth_conf *eth_conf, uint32_t num_devices)
-{
-	struct rte_eth_vmdq_rx_conf conf;
-	unsigned i;
-
-	memset(&conf, 0, sizeof(conf));
-	conf.nb_queue_pools = (enum rte_eth_nb_pools)num_devices;
-	conf.nb_pool_maps = num_devices;
-	conf.enable_loop_back =
-		vmdq_conf_default.rx_adv_conf.vmdq_rx_conf.enable_loop_back;
-
-	for (i = 0; i < conf.nb_pool_maps; i++) {
-		conf.pool_map[i].vlan_id = vlan_tags[ i ];
-		conf.pool_map[i].pools = (1UL << i);
-	}
-
-	(void)(rte_memcpy(eth_conf, &vmdq_conf_default, sizeof(*eth_conf)));
-	(void)(rte_memcpy(&eth_conf->rx_adv_conf.vmdq_rx_conf, &conf,
-		   sizeof(eth_conf->rx_adv_conf.vmdq_rx_conf)));
-	return 0;
-}
-
-/*
- * Validate the device number according to the max pool number gotten form
- * dev_info. If the device number is invalid, give the error message and
- * return -1. Each device must have its own pool.
- */
-static inline int
-validate_num_devices(uint32_t max_nb_devices)
-{
-	if (num_devices > max_nb_devices) {
-		RTE_LOG(ERR, VHOST_PORT, "invalid number of devices\n");
-		return -1;
-	}
-	return 0;
-}
-
-/*
- * Initialises a given port using global settings and with the rx buffers
- * coming from the mbuf_pool passed as parameter
- */
-static inline int
-port_init(uint8_t port)
-{
-	struct rte_eth_dev_info dev_info;
-	struct rte_eth_conf port_conf;
-	uint16_t rx_rings, tx_rings;
-	uint16_t rx_ring_size, tx_ring_size;
-	int retval;
-	uint16_t q;
-
-	/* The max pool number from dev_info will be used to validate the pool number specified in cmd line */
-	rte_eth_dev_info_get (port, &dev_info);
-
-	/*configure the number of supported virtio devices based on VMDQ limits */
-	num_devices = dev_info.max_vmdq_pools;
-	num_queues = dev_info.max_rx_queues;
-
-	if (zero_copy) {
-		rx_ring_size = num_rx_descriptor;
-		tx_ring_size = num_tx_descriptor;
-		tx_rings = dev_info.max_tx_queues;
-	} else {
-		rx_ring_size = RTE_TEST_RX_DESC_DEFAULT;
-		tx_ring_size = RTE_TEST_TX_DESC_DEFAULT;
-		tx_rings = (uint16_t)rte_lcore_count();
-	}
-
-	retval = validate_num_devices(MAX_DEVICES);
-	if (retval < 0)
-		return retval;
-
-	/* Get port configuration. */
-	retval = get_eth_conf(&port_conf, num_devices);
-	if (retval < 0)
-		return retval;
-
-	if (port >= rte_eth_dev_count()) return -1;
-
-	rx_rings = (uint16_t)num_queues,
-	/* Configure ethernet device. */
-	retval = rte_eth_dev_configure(port, rx_rings, tx_rings, &port_conf);
-	if (retval != 0)
-		return retval;
-
-	/* Setup the queues. */
-	for (q = 0; q < rx_rings; q ++) {
-		retval = rte_eth_rx_queue_setup(port, q, rx_ring_size,
-						rte_eth_dev_socket_id(port), &rx_conf_default,
-						vpool_array[q].pool);
-		if (retval < 0)
-			return retval;
-	}
-	for (q = 0; q < tx_rings; q ++) {
-		retval = rte_eth_tx_queue_setup(port, q, tx_ring_size,
-						rte_eth_dev_socket_id(port), &tx_conf_default);
-		if (retval < 0)
-			return retval;
-	}
-
-	/* Start the device. */
-	retval  = rte_eth_dev_start(port);
-	if (retval < 0) {
-		RTE_LOG(ERR, VHOST_DATA, "Failed to start the device.\n");
-		return retval;
-	}
-
-	rte_eth_macaddr_get(port, &vmdq_ports_eth_addr[port]);
-	RTE_LOG(INFO, VHOST_PORT, "Max virtio devices supported: %u\n", num_devices);
-	RTE_LOG(INFO, VHOST_PORT, "Port %u MAC: %02"PRIx8" %02"PRIx8" %02"PRIx8
-			" %02"PRIx8" %02"PRIx8" %02"PRIx8"\n",
-			(unsigned)port,
-			vmdq_ports_eth_addr[port].addr_bytes[0],
-			vmdq_ports_eth_addr[port].addr_bytes[1],
-			vmdq_ports_eth_addr[port].addr_bytes[2],
-			vmdq_ports_eth_addr[port].addr_bytes[3],
-			vmdq_ports_eth_addr[port].addr_bytes[4],
-			vmdq_ports_eth_addr[port].addr_bytes[5]);
-
-	return 0;
-}
-
-/*
- * Set character device basename.
- */
-static int
-us_vhost_parse_basename(const char *q_arg)
-{
-	/* parse number string */
-
-	if (strnlen(q_arg, MAX_BASENAME_SZ) > MAX_BASENAME_SZ)
-		return -1;
-	else
-		snprintf((char*)&dev_basename, MAX_BASENAME_SZ, "%s", q_arg);
-
-	return 0;
-}
-
-/*
- * Parse the portmask provided at run time.
- */
-static int
-parse_portmask(const char *portmask)
-{
-	char *end = NULL;
-	unsigned long pm;
-
-	errno = 0;
-
-	/* parse hexadecimal string */
-	pm = strtoul(portmask, &end, 16);
-	if ((portmask[0] == '\0') || (end == NULL) || (*end != '\0') || (errno != 0))
-		return -1;
-
-	if (pm == 0)
-		return -1;
-
-	return pm;
-
-}
-
-/*
- * Parse num options at run time.
- */
-static int
-parse_num_opt(const char *q_arg, uint32_t max_valid_value)
-{
-	char *end = NULL;
-	unsigned long num;
-
-	errno = 0;
-
-	/* parse unsigned int string */
-	num = strtoul(q_arg, &end, 10);
-	if ((q_arg[0] == '\0') || (end == NULL) || (*end != '\0') || (errno != 0))
-		return -1;
-
-	if (num > max_valid_value)
-		return -1;
-
-	return num;
-
-}
-
-/*
- * Display usage
- */
-static void
-us_vhost_usage(const char *prgname)
-{
-	RTE_LOG(INFO, VHOST_CONFIG, "%s [EAL options] -- -p PORTMASK\n"
-	"		--vm2vm [0|1|2]\n"
-	"		--rx_retry [0|1] --mergeable [0|1] --stats [0-N]\n"
-	"		--dev-basename <name> --dev-index [0-N]\n"
-	"		--nb-devices ND\n"
-	"		-p PORTMASK: Set mask for ports to be used by application\n"
-	"		--vm2vm [0|1|2]: disable/software(default)/hardware vm2vm comms\n"
-	"		--rx-retry [0|1]: disable/enable(default) retries on rx. Enable retry if destintation queue is full\n"
-	"		--rx-retry-delay [0-N]: timeout(in usecond) between retries on RX. This makes effect only if retries on rx enabled\n"
-	"		--rx-retry-num [0-N]: the number of retries on rx. This makes effect only if retries on rx enabled\n"
-	"		--mergeable [0|1]: disable(default)/enable RX mergeable buffers\n"
-	"		--stats [0-N]: 0: Disable stats, N: Time in seconds to print stats\n"
-	"		--dev-basename: The basename to be used for the character device.\n"
-	"		--dev-index [0-N]: Defaults to zero if not used. Index is appended to basename.\n"
-	"		--zero-copy [0|1]: disable(default)/enable rx/tx "
-			"zero copy\n"
-	"		--rx-desc-num [0-N]: the number of descriptors on rx, "
-			"used only when zero copy is enabled.\n"
-	"		--tx-desc-num [0-N]: the number of descriptors on tx, "
-			"used only when zero copy is enabled.\n",
-	       prgname);
-}
-
-/*
- * Parse the arguments given in the command line of the application.
- */
-static int
-us_vhost_parse_args(int argc, char **argv)
-{
-	int opt, ret;
-	int option_index;
-	unsigned i;
-	const char *prgname = argv[0];
-	static struct option long_option[] = {
-		{"vm2vm", required_argument, NULL, 0},
-		{"rx-retry", required_argument, NULL, 0},
-		{"rx-retry-delay", required_argument, NULL, 0},
-		{"rx-retry-num", required_argument, NULL, 0},
-		{"mergeable", required_argument, NULL, 0},
-		{"stats", required_argument, NULL, 0},
-		{"dev-basename", required_argument, NULL, 0},
-		{"dev-index", required_argument, NULL, 0},
-		{"zero-copy", required_argument, NULL, 0},
-		{"rx-desc-num", required_argument, NULL, 0},
-		{"tx-desc-num", required_argument, NULL, 0},
-		{NULL, 0, 0, 0},
-	};
-
-	/* Parse command line */
-	while ((opt = getopt_long(argc, argv, "p:",long_option, &option_index)) != EOF) {
-		switch (opt) {
-		/* Portmask */
-		case 'p':
-			enabled_port_mask = parse_portmask(optarg);
-			if (enabled_port_mask == 0) {
-				RTE_LOG(INFO, VHOST_CONFIG, "Invalid portmask\n");
-				us_vhost_usage(prgname);
-				return -1;
-			}
-			break;
-
-		case 0:
-			/* Enable/disable vm2vm comms. */
-			if (!strncmp(long_option[option_index].name, "vm2vm",
-				MAX_LONG_OPT_SZ)) {
-				ret = parse_num_opt(optarg, (VM2VM_LAST - 1));
-				if (ret == -1) {
-					RTE_LOG(INFO, VHOST_CONFIG,
-						"Invalid argument for "
-						"vm2vm [0|1|2]\n");
-					us_vhost_usage(prgname);
-					return -1;
-				} else {
-					vm2vm_mode = (vm2vm_type)ret;
-				}
-			}
-
-			/* Enable/disable retries on RX. */
-			if (!strncmp(long_option[option_index].name, "rx-retry", MAX_LONG_OPT_SZ)) {
-				ret = parse_num_opt(optarg, 1);
-				if (ret == -1) {
-					RTE_LOG(INFO, VHOST_CONFIG, "Invalid argument for rx-retry [0|1]\n");
-					us_vhost_usage(prgname);
-					return -1;
-				} else {
-					enable_retry = ret;
-				}
-			}
-
-			/* Specify the retries delay time (in useconds) on RX. */
-			if (!strncmp(long_option[option_index].name, "rx-retry-delay", MAX_LONG_OPT_SZ)) {
-				ret = parse_num_opt(optarg, INT32_MAX);
-				if (ret == -1) {
-					RTE_LOG(INFO, VHOST_CONFIG, "Invalid argument for rx-retry-delay [0-N]\n");
-					us_vhost_usage(prgname);
-					return -1;
-				} else {
-					burst_rx_delay_time = ret;
-				}
-			}
-
-			/* Specify the retries number on RX. */
-			if (!strncmp(long_option[option_index].name, "rx-retry-num", MAX_LONG_OPT_SZ)) {
-				ret = parse_num_opt(optarg, INT32_MAX);
-				if (ret == -1) {
-					RTE_LOG(INFO, VHOST_CONFIG, "Invalid argument for rx-retry-num [0-N]\n");
-					us_vhost_usage(prgname);
-					return -1;
-				} else {
-					burst_rx_retry_num = ret;
-				}
-			}
-
-			/* Enable/disable RX mergeable buffers. */
-			if (!strncmp(long_option[option_index].name, "mergeable", MAX_LONG_OPT_SZ)) {
-				ret = parse_num_opt(optarg, 1);
-				if (ret == -1) {
-					RTE_LOG(INFO, VHOST_CONFIG, "Invalid argument for mergeable [0|1]\n");
-					us_vhost_usage(prgname);
-					return -1;
-				} else {
-					if (ret) {
-						vmdq_conf_default.rxmode.jumbo_frame = 1;
-						vmdq_conf_default.rxmode.max_rx_pkt_len
-							= JUMBO_FRAME_MAX_SIZE;
-						VHOST_FEATURES = (1ULL << VIRTIO_NET_F_MRG_RXBUF);
-					}
-				}
-			}
-
-			/* Enable/disable stats. */
-			if (!strncmp(long_option[option_index].name, "stats", MAX_LONG_OPT_SZ)) {
-				ret = parse_num_opt(optarg, INT32_MAX);
-				if (ret == -1) {
-					RTE_LOG(INFO, VHOST_CONFIG, "Invalid argument for stats [0..N]\n");
-					us_vhost_usage(prgname);
-					return -1;
-				} else {
-					enable_stats = ret;
-				}
-			}
-
-			/* Set character device basename. */
-			if (!strncmp(long_option[option_index].name, "dev-basename", MAX_LONG_OPT_SZ)) {
-				if (us_vhost_parse_basename(optarg) == -1) {
-					RTE_LOG(INFO, VHOST_CONFIG, "Invalid argument for character device basename (Max %d characters)\n", MAX_BASENAME_SZ);
-					us_vhost_usage(prgname);
-					return -1;
-				}
-			}
-
-			/* Set character device index. */
-			if (!strncmp(long_option[option_index].name, "dev-index", MAX_LONG_OPT_SZ)) {
-				ret = parse_num_opt(optarg, INT32_MAX);
-				if (ret == -1) {
-					RTE_LOG(INFO, VHOST_CONFIG, "Invalid argument for character device index [0..N]\n");
-					us_vhost_usage(prgname);
-					return -1;
-				} else
-					dev_index = ret;
-			}
-
-			/* Enable/disable rx/tx zero copy. */
-			if (!strncmp(long_option[option_index].name,
-				"zero-copy", MAX_LONG_OPT_SZ)) {
-				ret = parse_num_opt(optarg, 1);
-				if (ret == -1) {
-					RTE_LOG(INFO, VHOST_CONFIG,
-						"Invalid argument"
-						" for zero-copy [0|1]\n");
-					us_vhost_usage(prgname);
-					return -1;
-				} else
-					zero_copy = ret;
-
-				if (zero_copy) {
-#ifdef RTE_MBUF_REFCNT
-					RTE_LOG(ERR, VHOST_CONFIG, "Before running "
-					"zero copy vhost APP, please "
-					"disable RTE_MBUF_REFCNT\n"
-					"in config file and then rebuild DPDK "
-					"core lib!\n"
-					"Otherwise please disable zero copy "
-					"flag in command line!\n");
-					return -1;
-#endif
-				}
-			}
-
-			/* Specify the descriptor number on RX. */
-			if (!strncmp(long_option[option_index].name,
-				"rx-desc-num", MAX_LONG_OPT_SZ)) {
-				ret = parse_num_opt(optarg, MAX_RING_DESC);
-				if ((ret == -1) || (!POWEROF2(ret))) {
-					RTE_LOG(INFO, VHOST_CONFIG,
-					"Invalid argument for rx-desc-num[0-N],"
-					"power of 2 required.\n");
-					us_vhost_usage(prgname);
-					return -1;
-				} else {
-					num_rx_descriptor = ret;
-				}
-			}
-
-			/* Specify the descriptor number on TX. */
-			if (!strncmp(long_option[option_index].name,
-				"tx-desc-num", MAX_LONG_OPT_SZ)) {
-				ret = parse_num_opt(optarg, MAX_RING_DESC);
-				if ((ret == -1) || (!POWEROF2(ret))) {
-					RTE_LOG(INFO, VHOST_CONFIG,
-					"Invalid argument for tx-desc-num [0-N],"
-					"power of 2 required.\n");
-					us_vhost_usage(prgname);
-					return -1;
-				} else {
-					num_tx_descriptor = ret;
-				}
-			}
-
-			break;
-
-			/* Invalid option - print options. */
-		default:
-			us_vhost_usage(prgname);
-			return -1;
-		}
-	}
-
-	for (i = 0; i < RTE_MAX_ETHPORTS; i++) {
-		if (enabled_port_mask & (1 << i))
-			ports[num_ports++] = (uint8_t)i;
-	}
-
-	if ((num_ports ==  0) || (num_ports > MAX_SUP_PORTS)) {
-		RTE_LOG(INFO, VHOST_PORT, "Current enabled port number is %u,"
-			"but only %u port can be enabled\n",num_ports, MAX_SUP_PORTS);
-		return -1;
-	}
-
-	if ((zero_copy == 1) && (vm2vm_mode == VM2VM_SOFTWARE)) {
-		RTE_LOG(INFO, VHOST_PORT,
-			"Vhost zero copy doesn't support software vm2vm,"
-			"please specify 'vm2vm 2' to use hardware vm2vm.\n");
-		return -1;
-	}
-
-	if ((zero_copy == 1) && (vmdq_conf_default.rxmode.jumbo_frame == 1)) {
-		RTE_LOG(INFO, VHOST_PORT,
-			"Vhost zero copy doesn't support jumbo frame,"
-			"please specify '--mergeable 0' to disable the "
-			"mergeable feature.\n");
-		return -1;
-	}
-
-	return 0;
-}
-
-/*
- * Update the global var NUM_PORTS and array PORTS according to system ports number
- * and return valid ports number
- */
-static unsigned check_ports_num(unsigned nb_ports)
-{
-	unsigned valid_num_ports = num_ports;
-	unsigned portid;
-
-	if (num_ports > nb_ports) {
-		RTE_LOG(INFO, VHOST_PORT, "\nSpecified port number(%u) exceeds total system port number(%u)\n",
-			num_ports, nb_ports);
-		num_ports = nb_ports;
-	}
-
-	for (portid = 0; portid < num_ports; portid ++) {
-		if (ports[portid] >= nb_ports) {
-			RTE_LOG(INFO, VHOST_PORT, "\nSpecified port ID(%u) exceeds max system port ID(%u)\n",
-				ports[portid], (nb_ports - 1));
-			ports[portid] = INVALID_PORT_ID;
-			valid_num_ports--;
-		}
-	}
-	return valid_num_ports;
-}
-
-/*
- * Macro to print out packet contents. Wrapped in debug define so that the
- * data path is not effected when debug is disabled.
- */
-#ifdef DEBUG
-#define PRINT_PACKET(device, addr, size, header) do {																\
-	char *pkt_addr = (char*)(addr);																					\
-	unsigned int index;																								\
-	char packet[MAX_PRINT_BUFF];																					\
-																													\
-	if ((header))																									\
-		snprintf(packet, MAX_PRINT_BUFF, "(%"PRIu64") Header size %d: ", (device->device_fh), (size));				\
-	else																											\
-		snprintf(packet, MAX_PRINT_BUFF, "(%"PRIu64") Packet size %d: ", (device->device_fh), (size));				\
-	for (index = 0; index < (size); index++) {																		\
-		snprintf(packet + strnlen(packet, MAX_PRINT_BUFF), MAX_PRINT_BUFF - strnlen(packet, MAX_PRINT_BUFF),	\
-			"%02hhx ", pkt_addr[index]);																			\
-	}																												\
-	snprintf(packet + strnlen(packet, MAX_PRINT_BUFF), MAX_PRINT_BUFF - strnlen(packet, MAX_PRINT_BUFF), "\n");	\
-																													\
-	LOG_DEBUG(VHOST_DATA, "%s", packet);																					\
-} while(0)
-#else
-#define PRINT_PACKET(device, addr, size, header) do{} while(0)
-#endif
-
-/*
- * Function to convert guest physical addresses to vhost virtual addresses. This
- * is used to convert virtio buffer addresses.
- */
-static inline uint64_t __attribute__((always_inline))
-gpa_to_vva(struct virtio_net *dev, uint64_t guest_pa)
-{
-	struct virtio_memory_regions *region;
-	uint32_t regionidx;
-	uint64_t vhost_va = 0;
-
-	for (regionidx = 0; regionidx < dev->mem->nregions; regionidx++) {
-		region = &dev->mem->regions[regionidx];
-		if ((guest_pa >= region->guest_phys_address) &&
-			(guest_pa <= region->guest_phys_address_end)) {
-			vhost_va = region->address_offset + guest_pa;
-			break;
-		}
-	}
-	LOG_DEBUG(VHOST_DATA, "(%"PRIu64") GPA %p| VVA %p\n",
-		dev->device_fh, (void*)(uintptr_t)guest_pa, (void*)(uintptr_t)vhost_va);
-
-	return vhost_va;
-}
-
-/*
- * Function to convert guest physical addresses to vhost physical addresses.
- * This is used to convert virtio buffer addresses.
- */
-static inline uint64_t __attribute__((always_inline))
-gpa_to_hpa(struct virtio_net *dev, uint64_t guest_pa,
-	uint32_t buf_len, hpa_type *addr_type)
-{
-	struct virtio_memory_regions_hpa *region;
-	uint32_t regionidx;
-	uint64_t vhost_pa = 0;
-
-	*addr_type = PHYS_ADDR_INVALID;
-
-	for (regionidx = 0; regionidx < dev->mem->nregions_hpa; regionidx++) {
-		region = &dev->mem->regions_hpa[regionidx];
-		if ((guest_pa >= region->guest_phys_address) &&
-			(guest_pa <= region->guest_phys_address_end)) {
-			vhost_pa = region->host_phys_addr_offset + guest_pa;
-			if (likely((guest_pa + buf_len - 1)
-				<= region->guest_phys_address_end))
-				*addr_type = PHYS_ADDR_CONTINUOUS;
-			else
-				*addr_type = PHYS_ADDR_CROSS_SUBREG;
-			break;
-		}
-	}
-
-	LOG_DEBUG(VHOST_DATA, "(%"PRIu64") GPA %p| HPA %p\n",
-		dev->device_fh, (void *)(uintptr_t)guest_pa,
-		(void *)(uintptr_t)vhost_pa);
-
-	return vhost_pa;
-}
-
-/*
- * This function adds buffers to the virtio devices RX virtqueue. Buffers can
- * be received from the physical port or from another virtio device. A packet
- * count is returned to indicate the number of packets that were succesfully
- * added to the RX queue. This function works when mergeable is disabled.
- */
-static inline uint32_t __attribute__((always_inline))
-virtio_dev_rx(struct virtio_net *dev, struct rte_mbuf **pkts, uint32_t count)
-{
-	struct vhost_virtqueue *vq;
-	struct vring_desc *desc;
-	struct rte_mbuf *buff;
-	/* The virtio_hdr is initialised to 0. */
-	struct virtio_net_hdr_mrg_rxbuf virtio_hdr = {{0,0,0,0,0,0},0};
-	uint64_t buff_addr = 0;
-	uint64_t buff_hdr_addr = 0;
-	uint32_t head[MAX_PKT_BURST], packet_len = 0;
-	uint32_t head_idx, packet_success = 0;
-	uint32_t retry = 0;
-	uint16_t avail_idx, res_cur_idx;
-	uint16_t res_base_idx, res_end_idx;
-	uint16_t free_entries;
-	uint8_t success = 0;
-
-	LOG_DEBUG(VHOST_DATA, "(%"PRIu64") virtio_dev_rx()\n", dev->device_fh);
-	vq = dev->virtqueue[VIRTIO_RXQ];
-	count = (count > MAX_PKT_BURST) ? MAX_PKT_BURST : count;
-
-	/* As many data cores may want access to available buffers, they need to be reserved. */
-	do {
-		res_base_idx = vq->last_used_idx_res;
-		avail_idx = *((volatile uint16_t *)&vq->avail->idx);
-
-		free_entries = (avail_idx - res_base_idx);
-		/* If retry is enabled and the queue is full then we wait and retry to avoid packet loss. */
-		if (enable_retry && unlikely(count > free_entries)) {
-			for (retry = 0; retry < burst_rx_retry_num; retry++) {
-				rte_delay_us(burst_rx_delay_time);
-				avail_idx =
-					*((volatile uint16_t *)&vq->avail->idx);
-				free_entries = (avail_idx - res_base_idx);
-				if (count <= free_entries)
-					break;
-			}
-		}
-
-		/*check that we have enough buffers*/
-		if (unlikely(count > free_entries))
-			count = free_entries;
-
-		if (count == 0)
-			return 0;
-
-		res_end_idx = res_base_idx + count;
-		/* vq->last_used_idx_res is atomically updated. */
-		success = rte_atomic16_cmpset(&vq->last_used_idx_res, res_base_idx,
-									res_end_idx);
-	} while (unlikely(success == 0));
-	res_cur_idx = res_base_idx;
-	LOG_DEBUG(VHOST_DATA, "(%"PRIu64") Current Index %d| End Index %d\n", dev->device_fh, res_cur_idx, res_end_idx);
-
-	/* Prefetch available ring to retrieve indexes. */
-	rte_prefetch0(&vq->avail->ring[res_cur_idx & (vq->size - 1)]);
-
-	/* Retrieve all of the head indexes first to avoid caching issues. */
-	for (head_idx = 0; head_idx < count; head_idx++)
-		head[head_idx] = vq->avail->ring[(res_cur_idx + head_idx) & (vq->size - 1)];
-
-	/*Prefetch descriptor index. */
-	rte_prefetch0(&vq->desc[head[packet_success]]);
-
-	while (res_cur_idx != res_end_idx) {
-		/* Get descriptor from available ring */
-		desc = &vq->desc[head[packet_success]];
-
-		buff = pkts[packet_success];
-
-		/* Convert from gpa to vva (guest physical addr -> vhost virtual addr) */
-		buff_addr = gpa_to_vva(dev, desc->addr);
-		/* Prefetch buffer address. */
-		rte_prefetch0((void*)(uintptr_t)buff_addr);
-
-		/* Copy virtio_hdr to packet and increment buffer address */
-		buff_hdr_addr = buff_addr;
-		packet_len = rte_pktmbuf_data_len(buff) + vq->vhost_hlen;
-
-		/*
-		 * If the descriptors are chained the header and data are
-		 * placed in separate buffers.
-		 */
-		if (desc->flags & VRING_DESC_F_NEXT) {
-			desc->len = vq->vhost_hlen;
-			desc = &vq->desc[desc->next];
-			/* Buffer address translation. */
-			buff_addr = gpa_to_vva(dev, desc->addr);
-			desc->len = rte_pktmbuf_data_len(buff);
-		} else {
-			buff_addr += vq->vhost_hlen;
-			desc->len = packet_len;
-		}
-
-		/* Update used ring with desc information */
-		vq->used->ring[res_cur_idx & (vq->size - 1)].id = head[packet_success];
-		vq->used->ring[res_cur_idx & (vq->size - 1)].len = packet_len;
-
-		/* Copy mbuf data to buffer */
-		rte_memcpy((void *)(uintptr_t)buff_addr,
-			rte_pktmbuf_mtod(buff, const void *),
-			rte_pktmbuf_data_len(buff));
-		PRINT_PACKET(dev, (uintptr_t)buff_addr,
-			rte_pktmbuf_data_len(buff), 0);
-
-		res_cur_idx++;
-		packet_success++;
-
-		rte_memcpy((void *)(uintptr_t)buff_hdr_addr,
-			(const void *)&virtio_hdr, vq->vhost_hlen);
-
-		PRINT_PACKET(dev, (uintptr_t)buff_hdr_addr, vq->vhost_hlen, 1);
-
-		if (res_cur_idx < res_end_idx) {
-			/* Prefetch descriptor index. */
-			rte_prefetch0(&vq->desc[head[packet_success]]);
-		}
-	}
-
-	rte_compiler_barrier();
-
-	/* Wait until it's our turn to add our buffer to the used ring. */
-	while (unlikely(vq->last_used_idx != res_base_idx))
-		rte_pause();
-
-	*(volatile uint16_t *)&vq->used->idx += count;
-	vq->last_used_idx = res_end_idx;
-
-	/* Kick the guest if necessary. */
-	if (!(vq->avail->flags & VRING_AVAIL_F_NO_INTERRUPT))
-		eventfd_write((int)vq->kickfd, 1);
-	return count;
-}
-
-static inline uint32_t __attribute__((always_inline))
-copy_from_mbuf_to_vring(struct virtio_net *dev,
-	uint16_t res_base_idx, uint16_t res_end_idx,
-	struct rte_mbuf *pkt)
-{
-	uint32_t vec_idx = 0;
-	uint32_t entry_success = 0;
-	struct vhost_virtqueue *vq;
-	/* The virtio_hdr is initialised to 0. */
-	struct virtio_net_hdr_mrg_rxbuf virtio_hdr = {
-		{0, 0, 0, 0, 0, 0}, 0};
-	uint16_t cur_idx = res_base_idx;
-	uint64_t vb_addr = 0;
-	uint64_t vb_hdr_addr = 0;
-	uint32_t seg_offset = 0;
-	uint32_t vb_offset = 0;
-	uint32_t seg_avail;
-	uint32_t vb_avail;
-	uint32_t cpy_len, entry_len;
-
-	if (pkt == NULL)
-		return 0;
-
-	LOG_DEBUG(VHOST_DATA, "(%"PRIu64") Current Index %d| "
-		"End Index %d\n",
-		dev->device_fh, cur_idx, res_end_idx);
-
-	/*
-	 * Convert from gpa to vva
-	 * (guest physical addr -> vhost virtual addr)
-	 */
-	vq = dev->virtqueue[VIRTIO_RXQ];
-	vb_addr =
-		gpa_to_vva(dev, vq->buf_vec[vec_idx].buf_addr);
-	vb_hdr_addr = vb_addr;
-
-	/* Prefetch buffer address. */
-	rte_prefetch0((void *)(uintptr_t)vb_addr);
-
-	virtio_hdr.num_buffers = res_end_idx - res_base_idx;
-
-	LOG_DEBUG(VHOST_DATA, "(%"PRIu64") RX: Num merge buffers %d\n",
-		dev->device_fh, virtio_hdr.num_buffers);
-
-	rte_memcpy((void *)(uintptr_t)vb_hdr_addr,
-		(const void *)&virtio_hdr, vq->vhost_hlen);
-
-	PRINT_PACKET(dev, (uintptr_t)vb_hdr_addr, vq->vhost_hlen, 1);
-
-	seg_avail = rte_pktmbuf_data_len(pkt);
-	vb_offset = vq->vhost_hlen;
-	vb_avail =
-		vq->buf_vec[vec_idx].buf_len - vq->vhost_hlen;
-
-	entry_len = vq->vhost_hlen;
-
-	if (vb_avail == 0) {
-		uint32_t desc_idx =
-			vq->buf_vec[vec_idx].desc_idx;
-		vq->desc[desc_idx].len = vq->vhost_hlen;
-
-		if ((vq->desc[desc_idx].flags
-			& VRING_DESC_F_NEXT) == 0) {
-			/* Update used ring with desc information */
-			vq->used->ring[cur_idx & (vq->size - 1)].id
-				= vq->buf_vec[vec_idx].desc_idx;
-			vq->used->ring[cur_idx & (vq->size - 1)].len
-				= entry_len;
-
-			entry_len = 0;
-			cur_idx++;
-			entry_success++;
-		}
-
-		vec_idx++;
-		vb_addr =
-			gpa_to_vva(dev, vq->buf_vec[vec_idx].buf_addr);
-
-		/* Prefetch buffer address. */
-		rte_prefetch0((void *)(uintptr_t)vb_addr);
-		vb_offset = 0;
-		vb_avail = vq->buf_vec[vec_idx].buf_len;
-	}
-
-	cpy_len = RTE_MIN(vb_avail, seg_avail);
-
-	while (cpy_len > 0) {
-		/* Copy mbuf data to vring buffer */
-		rte_memcpy((void *)(uintptr_t)(vb_addr + vb_offset),
-			(const void *)(rte_pktmbuf_mtod(pkt, char*) + seg_offset),
-			cpy_len);
-
-		PRINT_PACKET(dev,
-			(uintptr_t)(vb_addr + vb_offset),
-			cpy_len, 0);
-
-		seg_offset += cpy_len;
-		vb_offset += cpy_len;
-		seg_avail -= cpy_len;
-		vb_avail -= cpy_len;
-		entry_len += cpy_len;
-
-		if (seg_avail != 0) {
-			/*
-			 * The virtio buffer in this vring
-			 * entry reach to its end.
-			 * But the segment doesn't complete.
-			 */
-			if ((vq->desc[vq->buf_vec[vec_idx].desc_idx].flags &
-				VRING_DESC_F_NEXT) == 0) {
-				/* Update used ring with desc information */
-				vq->used->ring[cur_idx & (vq->size - 1)].id
-					= vq->buf_vec[vec_idx].desc_idx;
-				vq->used->ring[cur_idx & (vq->size - 1)].len
-					= entry_len;
-				entry_len = 0;
-				cur_idx++;
-				entry_success++;
-			}
-
-			vec_idx++;
-			vb_addr = gpa_to_vva(dev,
-				vq->buf_vec[vec_idx].buf_addr);
-			vb_offset = 0;
-			vb_avail = vq->buf_vec[vec_idx].buf_len;
-			cpy_len = RTE_MIN(vb_avail, seg_avail);
-		} else {
-			/*
-			 * This current segment complete, need continue to
-			 * check if the whole packet complete or not.
-			 */
-			pkt = pkt->next;
-			if (pkt != NULL) {
-				/*
-				 * There are more segments.
-				 */
-				if (vb_avail == 0) {
-					/*
-					 * This current buffer from vring is
-					 * used up, need fetch next buffer
-					 * from buf_vec.
-					 */
-					uint32_t desc_idx =
-						vq->buf_vec[vec_idx].desc_idx;
-					vq->desc[desc_idx].len = vb_offset;
-
-					if ((vq->desc[desc_idx].flags &
-						VRING_DESC_F_NEXT) == 0) {
-						uint16_t wrapped_idx =
-							cur_idx & (vq->size - 1);
-						/*
-						 * Update used ring with the
-						 * descriptor information
-						 */
-						vq->used->ring[wrapped_idx].id
-							= desc_idx;
-						vq->used->ring[wrapped_idx].len
-							= entry_len;
-						entry_success++;
-						entry_len = 0;
-						cur_idx++;
-					}
-
-					/* Get next buffer from buf_vec. */
-					vec_idx++;
-					vb_addr = gpa_to_vva(dev,
-						vq->buf_vec[vec_idx].buf_addr);
-					vb_avail =
-						vq->buf_vec[vec_idx].buf_len;
-					vb_offset = 0;
-				}
-
-				seg_offset = 0;
-				seg_avail = rte_pktmbuf_data_len(pkt);
-				cpy_len = RTE_MIN(vb_avail, seg_avail);
-			} else {
-				/*
-				 * This whole packet completes.
-				 */
-				uint32_t desc_idx =
-					vq->buf_vec[vec_idx].desc_idx;
-				vq->desc[desc_idx].len = vb_offset;
-
-				while (vq->desc[desc_idx].flags &
-					VRING_DESC_F_NEXT) {
-					desc_idx = vq->desc[desc_idx].next;
-					 vq->desc[desc_idx].len = 0;
-				}
-
-				/* Update used ring with desc information */
-				vq->used->ring[cur_idx & (vq->size - 1)].id
-					= vq->buf_vec[vec_idx].desc_idx;
-				vq->used->ring[cur_idx & (vq->size - 1)].len
-					= entry_len;
-				entry_len = 0;
-				cur_idx++;
-				entry_success++;
-				seg_avail = 0;
-				cpy_len = RTE_MIN(vb_avail, seg_avail);
-			}
-		}
-	}
-
-	return entry_success;
-}
-
-/*
- * This function adds buffers to the virtio devices RX virtqueue. Buffers can
- * be received from the physical port or from another virtio device. A packet
- * count is returned to indicate the number of packets that were succesfully
- * added to the RX queue. This function works for mergeable RX.
- */
-static inline uint32_t __attribute__((always_inline))
-virtio_dev_merge_rx(struct virtio_net *dev, struct rte_mbuf **pkts,
-	uint32_t count)
-{
-	struct vhost_virtqueue *vq;
-	uint32_t pkt_idx = 0, entry_success = 0;
-	uint32_t retry = 0;
-	uint16_t avail_idx, res_cur_idx;
-	uint16_t res_base_idx, res_end_idx;
-	uint8_t success = 0;
-
-	LOG_DEBUG(VHOST_DATA, "(%"PRIu64") virtio_dev_merge_rx()\n",
-		dev->device_fh);
-	vq = dev->virtqueue[VIRTIO_RXQ];
-	count = RTE_MIN((uint32_t)MAX_PKT_BURST, count);
-
-	if (count == 0)
-		return 0;
-
-	for (pkt_idx = 0; pkt_idx < count; pkt_idx++) {
-		uint32_t secure_len = 0;
-		uint16_t need_cnt;
-		uint32_t vec_idx = 0;
-		uint32_t pkt_len = pkts[pkt_idx]->pkt_len + vq->vhost_hlen;
-		uint16_t i, id;
-
-		do {
-			/*
-			 * As many data cores may want access to available
-			 * buffers, they need to be reserved.
-			 */
-			res_base_idx = vq->last_used_idx_res;
-			res_cur_idx = res_base_idx;
-
-			do {
-				avail_idx = *((volatile uint16_t *)&vq->avail->idx);
-				if (unlikely(res_cur_idx == avail_idx)) {
-					/*
-					 * If retry is enabled and the queue is
-					 * full then we wait and retry to avoid
-					 * packet loss.
-					 */
-					if (enable_retry) {
-						uint8_t cont = 0;
-						for (retry = 0; retry < burst_rx_retry_num; retry++) {
-							rte_delay_us(burst_rx_delay_time);
-							avail_idx =
-								*((volatile uint16_t *)&vq->avail->idx);
-							if (likely(res_cur_idx != avail_idx)) {
-								cont = 1;
-								break;
-							}
-						}
-						if (cont == 1)
-							continue;
-					}
-
-					LOG_DEBUG(VHOST_DATA,
-						"(%"PRIu64") Failed "
-						"to get enough desc from "
-						"vring\n",
-						dev->device_fh);
-					return pkt_idx;
-				} else {
-					uint16_t wrapped_idx =
-						(res_cur_idx) & (vq->size - 1);
-					uint32_t idx =
-						vq->avail->ring[wrapped_idx];
-					uint8_t next_desc;
-
-					do {
-						next_desc = 0;
-						secure_len += vq->desc[idx].len;
-						if (vq->desc[idx].flags &
-							VRING_DESC_F_NEXT) {
-							idx = vq->desc[idx].next;
-							next_desc = 1;
-						}
-					} while (next_desc);
-
-					res_cur_idx++;
-				}
-			} while (pkt_len > secure_len);
-
-			/* vq->last_used_idx_res is atomically updated. */
-			success = rte_atomic16_cmpset(&vq->last_used_idx_res,
-							res_base_idx,
-							res_cur_idx);
-		} while (success == 0);
-
-		id = res_base_idx;
-		need_cnt = res_cur_idx - res_base_idx;
-
-		for (i = 0; i < need_cnt; i++, id++) {
-			uint16_t wrapped_idx = id & (vq->size - 1);
-			uint32_t idx = vq->avail->ring[wrapped_idx];
-			uint8_t next_desc;
-			do {
-				next_desc = 0;
-				vq->buf_vec[vec_idx].buf_addr =
-					vq->desc[idx].addr;
-				vq->buf_vec[vec_idx].buf_len =
-					vq->desc[idx].len;
-				vq->buf_vec[vec_idx].desc_idx = idx;
-				vec_idx++;
-
-				if (vq->desc[idx].flags & VRING_DESC_F_NEXT) {
-					idx = vq->desc[idx].next;
-					next_desc = 1;
-				}
-			} while (next_desc);
-		}
-
-		res_end_idx = res_cur_idx;
-
-		entry_success = copy_from_mbuf_to_vring(dev, res_base_idx,
-			res_end_idx, pkts[pkt_idx]);
-
-		rte_compiler_barrier();
-
-		/*
-		 * Wait until it's our turn to add our buffer
-		 * to the used ring.
-		 */
-		while (unlikely(vq->last_used_idx != res_base_idx))
-			rte_pause();
-
-		*(volatile uint16_t *)&vq->used->idx += entry_success;
-		vq->last_used_idx = res_end_idx;
-
-		/* Kick the guest if necessary. */
-		if (!(vq->avail->flags & VRING_AVAIL_F_NO_INTERRUPT))
-			eventfd_write((int)vq->kickfd, 1);
-	}
-
-	return count;
-}
-
-/*
- * Compares a packet destination MAC address to a device MAC address.
- */
-static inline int __attribute__((always_inline))
-ether_addr_cmp(struct ether_addr *ea, struct ether_addr *eb)
-{
-	return (((*(uint64_t *)ea ^ *(uint64_t *)eb) & MAC_ADDR_CMP) == 0);
-}
-
-/*
- * This function learns the MAC address of the device and registers this along with a
- * vlan tag to a VMDQ.
- */
-static int
-link_vmdq(struct virtio_net *dev, struct rte_mbuf *m)
-{
-	struct ether_hdr *pkt_hdr;
-	struct virtio_net_data_ll *dev_ll;
-	int i, ret;
-
-	/* Learn MAC address of guest device from packet */
-	pkt_hdr = rte_pktmbuf_mtod(m, struct ether_hdr *);
-
-	dev_ll = ll_root_used;
-
-	while (dev_ll != NULL) {
-		if (ether_addr_cmp(&(pkt_hdr->s_addr), &dev_ll->dev->mac_address)) {
-			RTE_LOG(INFO, VHOST_DATA, "(%"PRIu64") WARNING: This device is using an existing MAC address and has not been registered.\n", dev->device_fh);
-			return -1;
-		}
-		dev_ll = dev_ll->next;
-	}
-
-	for (i = 0; i < ETHER_ADDR_LEN; i++)
-		dev->mac_address.addr_bytes[i] = pkt_hdr->s_addr.addr_bytes[i];
-
-	/* vlan_tag currently uses the device_id. */
-	dev->vlan_tag = vlan_tags[dev->device_fh];
-
-	/* Print out VMDQ registration info. */
-	RTE_LOG(INFO, VHOST_DATA, "(%"PRIu64") MAC_ADDRESS %02x:%02x:%02x:%02x:%02x:%02x and VLAN_TAG %d registered\n",
-		dev->device_fh,
-		dev->mac_address.addr_bytes[0], dev->mac_address.addr_bytes[1],
-		dev->mac_address.addr_bytes[2], dev->mac_address.addr_bytes[3],
-		dev->mac_address.addr_bytes[4], dev->mac_address.addr_bytes[5],
-		dev->vlan_tag);
-
-	/* Register the MAC address. */
-	ret = rte_eth_dev_mac_addr_add(ports[0], &dev->mac_address, (uint32_t)dev->device_fh);
-	if (ret)
-		RTE_LOG(ERR, VHOST_DATA, "(%"PRIu64") Failed to add device MAC address to VMDQ\n",
-					dev->device_fh);
-
-	/* Enable stripping of the vlan tag as we handle routing. */
-	rte_eth_dev_set_vlan_strip_on_queue(ports[0], (uint16_t)dev->vmdq_rx_q, 1);
-
-	/* Set device as ready for RX. */
-	dev->ready = DEVICE_RX;
-
-	return 0;
-}
-
-/*
- * Removes MAC address and vlan tag from VMDQ. Ensures that nothing is adding buffers to the RX
- * queue before disabling RX on the device.
- */
-static inline void
-unlink_vmdq(struct virtio_net *dev)
-{
-	unsigned i = 0;
-	unsigned rx_count;
-	struct rte_mbuf *pkts_burst[MAX_PKT_BURST];
-
-	if (dev->ready == DEVICE_RX) {
-		/*clear MAC and VLAN settings*/
-		rte_eth_dev_mac_addr_remove(ports[0], &dev->mac_address);
-		for (i = 0; i < 6; i++)
-			dev->mac_address.addr_bytes[i] = 0;
-
-		dev->vlan_tag = 0;
-
-		/*Clear out the receive buffers*/
-		rx_count = rte_eth_rx_burst(ports[0],
-					(uint16_t)dev->vmdq_rx_q, pkts_burst, MAX_PKT_BURST);
-
-		while (rx_count) {
-			for (i = 0; i < rx_count; i++)
-				rte_pktmbuf_free(pkts_burst[i]);
-
-			rx_count = rte_eth_rx_burst(ports[0],
-					(uint16_t)dev->vmdq_rx_q, pkts_burst, MAX_PKT_BURST);
-		}
-
-		dev->ready = DEVICE_MAC_LEARNING;
-	}
-}
-
-/*
- * Check if the packet destination MAC address is for a local device. If so then put
- * the packet on that devices RX queue. If not then return.
- */
-static inline unsigned __attribute__((always_inline))
-virtio_tx_local(struct virtio_net *dev, struct rte_mbuf *m)
-{
-	struct virtio_net_data_ll *dev_ll;
-	struct ether_hdr *pkt_hdr;
-	uint64_t ret = 0;
-
-	pkt_hdr = rte_pktmbuf_mtod(m, struct ether_hdr *);
-
-	/*get the used devices list*/
-	dev_ll = ll_root_used;
-
-	while (dev_ll != NULL) {
-		if ((dev_ll->dev->ready == DEVICE_RX) && ether_addr_cmp(&(pkt_hdr->d_addr),
-				          &dev_ll->dev->mac_address)) {
-
-			/* Drop the packet if the TX packet is destined for the TX device. */
-			if (dev_ll->dev->device_fh == dev->device_fh) {
-				LOG_DEBUG(VHOST_DATA, "(%"PRIu64") TX: Source and destination MAC addresses are the same. Dropping packet.\n",
-							dev_ll->dev->device_fh);
-				return 0;
-			}
-
-
-			LOG_DEBUG(VHOST_DATA, "(%"PRIu64") TX: MAC address is local\n", dev_ll->dev->device_fh);
-
-			if (dev_ll->dev->remove) {
-				/*drop the packet if the device is marked for removal*/
-				LOG_DEBUG(VHOST_DATA, "(%"PRIu64") Device is marked for removal\n", dev_ll->dev->device_fh);
-			} else {
-				uint32_t mergeable =
-					dev_ll->dev->features &
-					(1 << VIRTIO_NET_F_MRG_RXBUF);
-
-				/*send the packet to the local virtio device*/
-				if (likely(mergeable == 0))
-					ret = virtio_dev_rx(dev_ll->dev, &m, 1);
-				else
-					ret = virtio_dev_merge_rx(dev_ll->dev,
-						&m, 1);
-
-				if (enable_stats) {
-					rte_atomic64_add(
-					&dev_statistics[dev_ll->dev->device_fh].rx_total_atomic,
-					1);
-					rte_atomic64_add(
-					&dev_statistics[dev_ll->dev->device_fh].rx_atomic,
-					ret);
-					dev_statistics[dev->device_fh].tx_total++;
-					dev_statistics[dev->device_fh].tx += ret;
-				}
-			}
-
-			return 0;
-		}
-		dev_ll = dev_ll->next;
-	}
-
-	return -1;
-}
-
-/*
- * This function routes the TX packet to the correct interface. This may be a local device
- * or the physical port.
- */
-static inline void __attribute__((always_inline))
-virtio_tx_route(struct virtio_net* dev, struct rte_mbuf *m, struct rte_mempool *mbuf_pool, uint16_t vlan_tag)
-{
-	struct mbuf_table *tx_q;
-	struct vlan_ethhdr *vlan_hdr;
-	struct rte_mbuf **m_table;
-	struct rte_mbuf *mbuf, *prev;
-	unsigned len, ret, offset = 0;
-	const uint16_t lcore_id = rte_lcore_id();
-	struct virtio_net_data_ll *dev_ll = ll_root_used;
-	struct ether_hdr *pkt_hdr = rte_pktmbuf_mtod(m, struct ether_hdr *);
-
-	/*check if destination is local VM*/
-	if ((vm2vm_mode == VM2VM_SOFTWARE) && (virtio_tx_local(dev, m) == 0))
-		return;
-
-	if (vm2vm_mode == VM2VM_HARDWARE) {
-		while (dev_ll != NULL) {
-			if ((dev_ll->dev->ready == DEVICE_RX)
-				&& ether_addr_cmp(&(pkt_hdr->d_addr),
-				&dev_ll->dev->mac_address)) {
-				/*
-				 * Drop the packet if the TX packet is
-				 * destined for the TX device.
-				 */
-				if (dev_ll->dev->device_fh == dev->device_fh) {
-					LOG_DEBUG(VHOST_DATA,
-					"(%"PRIu64") TX: Source and destination"
-					" MAC addresses are the same. Dropping "
-					"packet.\n",
-					dev_ll->dev->device_fh);
-					return;
-				}
-				offset = 4;
-				vlan_tag =
-				(uint16_t)
-				vlan_tags[(uint16_t)dev_ll->dev->device_fh];
-
-				LOG_DEBUG(VHOST_DATA,
-				"(%"PRIu64") TX: pkt to local VM device id:"
-				"(%"PRIu64") vlan tag: %d.\n",
-				dev->device_fh, dev_ll->dev->device_fh,
-				vlan_tag);
-
-				break;
-			}
-			dev_ll = dev_ll->next;
-		}
-	}
-
-	LOG_DEBUG(VHOST_DATA, "(%"PRIu64") TX: MAC address is external\n", dev->device_fh);
-
-	/*Add packet to the port tx queue*/
-	tx_q = &lcore_tx_queue[lcore_id];
-	len = tx_q->len;
-
-	/* Allocate an mbuf and populate the structure. */
-	mbuf = rte_pktmbuf_alloc(mbuf_pool);
-	if (unlikely(mbuf == NULL)) {
-		RTE_LOG(ERR, VHOST_DATA,
-			"Failed to allocate memory for mbuf.\n");
-		return;
-	}
-
-	mbuf->data_len = m->data_len + VLAN_HLEN + offset;
-	mbuf->pkt_len = m->pkt_len + VLAN_HLEN + offset;
-	mbuf->nb_segs = m->nb_segs;
-
-	/* Copy ethernet header to mbuf. */
-	rte_memcpy(rte_pktmbuf_mtod(mbuf, void *),
-		rte_pktmbuf_mtod(m, const void *),
-		ETH_HLEN);
-
-
-	/* Setup vlan header. Bytes need to be re-ordered for network with htons()*/
-	vlan_hdr = rte_pktmbuf_mtod(mbuf, struct vlan_ethhdr *);
-	vlan_hdr->h_vlan_encapsulated_proto = vlan_hdr->h_vlan_proto;
-	vlan_hdr->h_vlan_proto = htons(ETH_P_8021Q);
-	vlan_hdr->h_vlan_TCI = htons(vlan_tag);
-
-	/* Copy the remaining packet contents to the mbuf. */
-	rte_memcpy((void *)(rte_pktmbuf_mtod(mbuf, uint8_t *) + VLAN_ETH_HLEN),
-		(const void *)(rte_pktmbuf_mtod(m, uint8_t *) + ETH_HLEN),
-		(m->data_len - ETH_HLEN));
-
-	/* Copy the remaining segments for the whole packet. */
-	prev = mbuf;
-	while (m->next) {
-		/* Allocate an mbuf and populate the structure. */
-		struct rte_mbuf *next_mbuf = rte_pktmbuf_alloc(mbuf_pool);
-		if (unlikely(next_mbuf == NULL)) {
-			rte_pktmbuf_free(mbuf);
-			RTE_LOG(ERR, VHOST_DATA,
-				"Failed to allocate memory for mbuf.\n");
-			return;
-		}
-
-		m = m->next;
-		prev->next = next_mbuf;
-		prev = next_mbuf;
-		next_mbuf->data_len = m->data_len;
-
-		/* Copy data to next mbuf. */
-		rte_memcpy(rte_pktmbuf_mtod(next_mbuf, void *),
-			rte_pktmbuf_mtod(m, const void *), m->data_len);
-	}
-
-	tx_q->m_table[len] = mbuf;
-	len++;
-	if (enable_stats) {
-		dev_statistics[dev->device_fh].tx_total++;
-		dev_statistics[dev->device_fh].tx++;
-	}
-
-	if (unlikely(len == MAX_PKT_BURST)) {
-		m_table = (struct rte_mbuf **)tx_q->m_table;
-		ret = rte_eth_tx_burst(ports[0], (uint16_t)tx_q->txq_id, m_table, (uint16_t) len);
-		/* Free any buffers not handled by TX and update the port stats. */
-		if (unlikely(ret < len)) {
-			do {
-				rte_pktmbuf_free(m_table[ret]);
-			} while (++ret < len);
-		}
-
-		len = 0;
-	}
-
-	tx_q->len = len;
-	return;
-}
-
-static inline void __attribute__((always_inline))
-virtio_dev_tx(struct virtio_net* dev, struct rte_mempool *mbuf_pool)
-{
-	struct rte_mbuf m;
-	struct vhost_virtqueue *vq;
-	struct vring_desc *desc;
-	uint64_t buff_addr = 0;
-	uint32_t head[MAX_PKT_BURST];
-	uint32_t used_idx;
-	uint32_t i;
-	uint16_t free_entries, packet_success = 0;
-	uint16_t avail_idx;
-
-	vq = dev->virtqueue[VIRTIO_TXQ];
-	avail_idx =  *((volatile uint16_t *)&vq->avail->idx);
-
-	/* If there are no available buffers then return. */
-	if (vq->last_used_idx == avail_idx)
-		return;
-
-	LOG_DEBUG(VHOST_DATA, "(%"PRIu64") virtio_dev_tx()\n", dev->device_fh);
-
-	/* Prefetch available ring to retrieve head indexes. */
-	rte_prefetch0(&vq->avail->ring[vq->last_used_idx & (vq->size - 1)]);
-
-	/*get the number of free entries in the ring*/
-	free_entries = (avail_idx - vq->last_used_idx);
-
-	/* Limit to MAX_PKT_BURST. */
-	if (free_entries > MAX_PKT_BURST)
-		free_entries = MAX_PKT_BURST;
-
-	LOG_DEBUG(VHOST_DATA, "(%"PRIu64") Buffers available %d\n", dev->device_fh, free_entries);
-	/* Retrieve all of the head indexes first to avoid caching issues. */
-	for (i = 0; i < free_entries; i++)
-		head[i] = vq->avail->ring[(vq->last_used_idx + i) & (vq->size - 1)];
-
-	/* Prefetch descriptor index. */
-	rte_prefetch0(&vq->desc[head[packet_success]]);
-	rte_prefetch0(&vq->used->ring[vq->last_used_idx & (vq->size - 1)]);
-
-	while (packet_success < free_entries) {
-		desc = &vq->desc[head[packet_success]];
-
-		/* Discard first buffer as it is the virtio header */
-		desc = &vq->desc[desc->next];
-
-		/* Buffer address translation. */
-		buff_addr = gpa_to_vva(dev, desc->addr);
-		/* Prefetch buffer address. */
-		rte_prefetch0((void*)(uintptr_t)buff_addr);
-
-		used_idx = vq->last_used_idx & (vq->size - 1);
-
-		if (packet_success < (free_entries - 1)) {
-			/* Prefetch descriptor index. */
-			rte_prefetch0(&vq->desc[head[packet_success+1]]);
-			rte_prefetch0(&vq->used->ring[(used_idx + 1) & (vq->size - 1)]);
-		}
-
-		/* Update used index buffer information. */
-		vq->used->ring[used_idx].id = head[packet_success];
-		vq->used->ring[used_idx].len = 0;
-
-		/* Setup dummy mbuf. This is copied to a real mbuf if transmitted out the physical port. */
-		m.data_len = desc->len;
-		m.pkt_len = desc->len;
-		m.data_off = 0;
-
-		PRINT_PACKET(dev, (uintptr_t)buff_addr, desc->len, 0);
-
-		/* If this is the first received packet we need to learn the MAC and setup VMDQ */
-		if (dev->ready == DEVICE_MAC_LEARNING) {
-			if (dev->remove || (link_vmdq(dev, &m) == -1)) {
-				/*discard frame if device is scheduled for removal or a duplicate MAC address is found. */
-				packet_success += free_entries;
-				vq->last_used_idx += packet_success;
-				break;
-			}
-		}
-		virtio_tx_route(dev, &m, mbuf_pool, (uint16_t)dev->device_fh);
-
-		vq->last_used_idx++;
-		packet_success++;
-	}
-
-	rte_compiler_barrier();
-	vq->used->idx += packet_success;
-	/* Kick guest if required. */
-	if (!(vq->avail->flags & VRING_AVAIL_F_NO_INTERRUPT))
-		eventfd_write((int)vq->kickfd, 1);
-}
-
-/* This function works for TX packets with mergeable feature enabled. */
-static inline void __attribute__((always_inline))
-virtio_dev_merge_tx(struct virtio_net *dev, struct rte_mempool *mbuf_pool)
-{
-	struct rte_mbuf *m, *prev;
-	struct vhost_virtqueue *vq;
-	struct vring_desc *desc;
-	uint64_t vb_addr = 0;
-	uint32_t head[MAX_PKT_BURST];
-	uint32_t used_idx;
-	uint32_t i;
-	uint16_t free_entries, entry_success = 0;
-	uint16_t avail_idx;
-	uint32_t buf_size = MBUF_SIZE - (sizeof(struct rte_mbuf)
-			+ RTE_PKTMBUF_HEADROOM);
-
-	vq = dev->virtqueue[VIRTIO_TXQ];
-	avail_idx =  *((volatile uint16_t *)&vq->avail->idx);
-
-	/* If there are no available buffers then return. */
-	if (vq->last_used_idx == avail_idx)
-		return;
-
-	LOG_DEBUG(VHOST_DATA, "(%"PRIu64") virtio_dev_merge_tx()\n",
-		dev->device_fh);
-
-	/* Prefetch available ring to retrieve head indexes. */
-	rte_prefetch0(&vq->avail->ring[vq->last_used_idx & (vq->size - 1)]);
-
-	/*get the number of free entries in the ring*/
-	free_entries = (avail_idx - vq->last_used_idx);
-
-	/* Limit to MAX_PKT_BURST. */
-	free_entries = RTE_MIN(free_entries, MAX_PKT_BURST);
-
-	LOG_DEBUG(VHOST_DATA, "(%"PRIu64") Buffers available %d\n",
-		dev->device_fh, free_entries);
-	/* Retrieve all of the head indexes first to avoid caching issues. */
-	for (i = 0; i < free_entries; i++)
-		head[i] = vq->avail->ring[(vq->last_used_idx + i) & (vq->size - 1)];
-
-	/* Prefetch descriptor index. */
-	rte_prefetch0(&vq->desc[head[entry_success]]);
-	rte_prefetch0(&vq->used->ring[vq->last_used_idx & (vq->size - 1)]);
-
-	while (entry_success < free_entries) {
-		uint32_t vb_avail, vb_offset;
-		uint32_t seg_avail, seg_offset;
-		uint32_t cpy_len;
-		uint32_t seg_num = 0;
-		struct rte_mbuf *cur;
-		uint8_t alloc_err = 0;
-
-		desc = &vq->desc[head[entry_success]];
-
-		/* Discard first buffer as it is the virtio header */
-		desc = &vq->desc[desc->next];
-
-		/* Buffer address translation. */
-		vb_addr = gpa_to_vva(dev, desc->addr);
-		/* Prefetch buffer address. */
-		rte_prefetch0((void *)(uintptr_t)vb_addr);
-
-		used_idx = vq->last_used_idx & (vq->size - 1);
-
-		if (entry_success < (free_entries - 1)) {
-			/* Prefetch descriptor index. */
-			rte_prefetch0(&vq->desc[head[entry_success+1]]);
-			rte_prefetch0(&vq->used->ring[(used_idx + 1) & (vq->size - 1)]);
-		}
-
-		/* Update used index buffer information. */
-		vq->used->ring[used_idx].id = head[entry_success];
-		vq->used->ring[used_idx].len = 0;
-
-		vb_offset = 0;
-		vb_avail = desc->len;
-		seg_offset = 0;
-		seg_avail = buf_size;
-		cpy_len = RTE_MIN(vb_avail, seg_avail);
-
-		PRINT_PACKET(dev, (uintptr_t)vb_addr, desc->len, 0);
-
-		/* Allocate an mbuf and populate the structure. */
-		m = rte_pktmbuf_alloc(mbuf_pool);
-		if (unlikely(m == NULL)) {
-			RTE_LOG(ERR, VHOST_DATA,
-				"Failed to allocate memory for mbuf.\n");
-			return;
-		}
-
-		seg_num++;
-		cur = m;
-		prev = m;
-		while (cpy_len != 0) {
-			rte_memcpy((void *)(rte_pktmbuf_mtod(cur, char *) + seg_offset),
-				(void *)((uintptr_t)(vb_addr + vb_offset)),
-				cpy_len);
-
-			seg_offset += cpy_len;
-			vb_offset += cpy_len;
-			vb_avail -= cpy_len;
-			seg_avail -= cpy_len;
-
-			if (vb_avail != 0) {
-				/*
-				 * The segment reachs to its end,
-				 * while the virtio buffer in TX vring has
-				 * more data to be copied.
-				 */
-				cur->data_len = seg_offset;
-				m->pkt_len += seg_offset;
-				/* Allocate mbuf and populate the structure. */
-				cur = rte_pktmbuf_alloc(mbuf_pool);
-				if (unlikely(cur == NULL)) {
-					RTE_LOG(ERR, VHOST_DATA, "Failed to "
-						"allocate memory for mbuf.\n");
-					rte_pktmbuf_free(m);
-					alloc_err = 1;
-					break;
-				}
-
-				seg_num++;
-				prev->next = cur;
-				prev = cur;
-				seg_offset = 0;
-				seg_avail = buf_size;
-			} else {
-				if (desc->flags & VRING_DESC_F_NEXT) {
-					/*
-					 * There are more virtio buffers in
-					 * same vring entry need to be copied.
-					 */
-					if (seg_avail == 0) {
-						/*
-						 * The current segment hasn't
-						 * room to accomodate more
-						 * data.
-						 */
-						cur->data_len = seg_offset;
-						m->pkt_len += seg_offset;
-						/*
-						 * Allocate an mbuf and
-						 * populate the structure.
-						 */
-						cur = rte_pktmbuf_alloc(mbuf_pool);
-						if (unlikely(cur == NULL)) {
-							RTE_LOG(ERR,
-								VHOST_DATA,
-								"Failed to "
-								"allocate memory "
-								"for mbuf\n");
-							rte_pktmbuf_free(m);
-							alloc_err = 1;
-							break;
-						}
-						seg_num++;
-						prev->next = cur;
-						prev = cur;
-						seg_offset = 0;
-						seg_avail = buf_size;
-					}
-
-					desc = &vq->desc[desc->next];
-
-					/* Buffer address translation. */
-					vb_addr = gpa_to_vva(dev, desc->addr);
-					/* Prefetch buffer address. */
-					rte_prefetch0((void *)(uintptr_t)vb_addr);
-					vb_offset = 0;
-					vb_avail = desc->len;
-
-					PRINT_PACKET(dev, (uintptr_t)vb_addr,
-						desc->len, 0);
-				} else {
-					/* The whole packet completes. */
-					cur->data_len = seg_offset;
-					m->pkt_len += seg_offset;
-					vb_avail = 0;
-				}
-			}
-
-			cpy_len = RTE_MIN(vb_avail, seg_avail);
-		}
-
-		if (unlikely(alloc_err == 1))
-			break;
-
-		m->nb_segs = seg_num;
-
-		/*
-		 * If this is the first received packet we need to learn
-		 * the MAC and setup VMDQ
-		 */
-		if (dev->ready == DEVICE_MAC_LEARNING) {
-			if (dev->remove || (link_vmdq(dev, m) == -1)) {
-				/*
-				 * Discard frame if device is scheduled for
-				 * removal or a duplicate MAC address is found.
-				 */
-				entry_success = free_entries;
-				vq->last_used_idx += entry_success;
-				rte_pktmbuf_free(m);
-				break;
-			}
-		}
-
-		virtio_tx_route(dev, m, mbuf_pool, (uint16_t)dev->device_fh);
-		vq->last_used_idx++;
-		entry_success++;
-		rte_pktmbuf_free(m);
-	}
-
-	rte_compiler_barrier();
-	vq->used->idx += entry_success;
-	/* Kick guest if required. */
-	if (!(vq->avail->flags & VRING_AVAIL_F_NO_INTERRUPT))
-		eventfd_write((int)vq->kickfd, 1);
-
-}
-
-/*
- * This function is called by each data core. It handles all RX/TX registered with the
- * core. For TX the specific lcore linked list is used. For RX, MAC addresses are compared
- * with all devices in the main linked list.
- */
-static int
-switch_worker(__attribute__((unused)) void *arg)
-{
-	struct rte_mempool *mbuf_pool = arg;
-	struct virtio_net *dev = NULL;
-	struct rte_mbuf *pkts_burst[MAX_PKT_BURST];
-	struct virtio_net_data_ll *dev_ll;
-	struct mbuf_table *tx_q;
-	volatile struct lcore_ll_info *lcore_ll;
-	const uint64_t drain_tsc = (rte_get_tsc_hz() + US_PER_S - 1) / US_PER_S * BURST_TX_DRAIN_US;
-	uint64_t prev_tsc, diff_tsc, cur_tsc, ret_count = 0;
-	unsigned ret, i;
-	const uint16_t lcore_id = rte_lcore_id();
-	const uint16_t num_cores = (uint16_t)rte_lcore_count();
-	uint16_t rx_count = 0;
-	uint32_t mergeable = 0;
-
-	RTE_LOG(INFO, VHOST_DATA, "Procesing on Core %u started\n", lcore_id);
-	lcore_ll = lcore_info[lcore_id].lcore_ll;
-	prev_tsc = 0;
-
-	tx_q = &lcore_tx_queue[lcore_id];
-	for (i = 0; i < num_cores; i ++) {
-		if (lcore_ids[i] == lcore_id) {
-			tx_q->txq_id = i;
-			break;
-		}
-	}
-
-	while(1) {
-		cur_tsc = rte_rdtsc();
-		/*
-		 * TX burst queue drain
-		 */
-		diff_tsc = cur_tsc - prev_tsc;
-		if (unlikely(diff_tsc > drain_tsc)) {
-
-			if (tx_q->len) {
-				LOG_DEBUG(VHOST_DATA, "TX queue drained after timeout with burst size %u \n", tx_q->len);
-
-				/*Tx any packets in the queue*/
-				ret = rte_eth_tx_burst(ports[0], (uint16_t)tx_q->txq_id,
-									   (struct rte_mbuf **)tx_q->m_table,
-									   (uint16_t)tx_q->len);
-				if (unlikely(ret < tx_q->len)) {
-					do {
-						rte_pktmbuf_free(tx_q->m_table[ret]);
-					} while (++ret < tx_q->len);
-				}
-
-				tx_q->len = 0;
-			}
-
-			prev_tsc = cur_tsc;
-
-		}
-
-		rte_prefetch0(lcore_ll->ll_root_used);
-		/*
-		 * Inform the configuration core that we have exited the linked list and that no devices are
-		 * in use if requested.
-		 */
-		if (lcore_ll->dev_removal_flag == REQUEST_DEV_REMOVAL)
-			lcore_ll->dev_removal_flag = ACK_DEV_REMOVAL;
-
-		/*
-		 * Process devices
-		 */
-		dev_ll = lcore_ll->ll_root_used;
-
-		while (dev_ll != NULL) {
-			/*get virtio device ID*/
-			dev = dev_ll->dev;
-			mergeable =
-				dev->features & (1 << VIRTIO_NET_F_MRG_RXBUF);
-
-			if (dev->remove) {
-				dev_ll = dev_ll->next;
-				unlink_vmdq(dev);
-				dev->ready = DEVICE_SAFE_REMOVE;
-				continue;
-			}
-			if (likely(dev->ready == DEVICE_RX)) {
-				/*Handle guest RX*/
-				rx_count = rte_eth_rx_burst(ports[0],
-					(uint16_t)dev->vmdq_rx_q, pkts_burst, MAX_PKT_BURST);
-
-				if (rx_count) {
-					if (likely(mergeable == 0))
-						ret_count =
-							virtio_dev_rx(dev,
-							pkts_burst, rx_count);
-					else
-						ret_count =
-							virtio_dev_merge_rx(dev,
-							pkts_burst, rx_count);
-
-					if (enable_stats) {
-						rte_atomic64_add(
-						&dev_statistics[dev_ll->dev->device_fh].rx_total_atomic,
-						rx_count);
-						rte_atomic64_add(
-						&dev_statistics[dev_ll->dev->device_fh].rx_atomic, ret_count);
-					}
-					while (likely(rx_count)) {
-						rx_count--;
-						rte_pktmbuf_free(pkts_burst[rx_count]);
-					}
-
-				}
-			}
-
-			if (!dev->remove) {
-				/*Handle guest TX*/
-				if (likely(mergeable == 0))
-					virtio_dev_tx(dev, mbuf_pool);
-				else
-					virtio_dev_merge_tx(dev, mbuf_pool);
-			}
-
-			/*move to the next device in the list*/
-			dev_ll = dev_ll->next;
-		}
-	}
-
-	return 0;
-}
-
-/*
- * This function gets available ring number for zero copy rx.
- * Only one thread will call this funciton for a paticular virtio device,
- * so, it is designed as non-thread-safe function.
- */
-static inline uint32_t __attribute__((always_inline))
-get_available_ring_num_zcp(struct virtio_net *dev)
-{
-	struct vhost_virtqueue *vq = dev->virtqueue[VIRTIO_RXQ];
-	uint16_t avail_idx;
-
-	avail_idx = *((volatile uint16_t *)&vq->avail->idx);
-	return (uint32_t)(avail_idx - vq->last_used_idx_res);
-}
-
-/*
- * This function gets available ring index for zero copy rx,
- * it will retry 'burst_rx_retry_num' times till it get enough ring index.
- * Only one thread will call this funciton for a paticular virtio device,
- * so, it is designed as non-thread-safe function.
- */
-static inline uint32_t __attribute__((always_inline))
-get_available_ring_index_zcp(struct virtio_net *dev,
-	uint16_t *res_base_idx, uint32_t count)
-{
-	struct vhost_virtqueue *vq = dev->virtqueue[VIRTIO_RXQ];
-	uint16_t avail_idx;
-	uint32_t retry = 0;
-	uint16_t free_entries;
-
-	*res_base_idx = vq->last_used_idx_res;
-	avail_idx = *((volatile uint16_t *)&vq->avail->idx);
-	free_entries = (avail_idx - *res_base_idx);
-
-	LOG_DEBUG(VHOST_DATA, "(%"PRIu64") in get_available_ring_index_zcp: "
-			"avail idx: %d, "
-			"res base idx:%d, free entries:%d\n",
-			dev->device_fh, avail_idx, *res_base_idx,
-			free_entries);
-
-	/*
-	 * If retry is enabled and the queue is full then we wait
-	 * and retry to avoid packet loss.
-	 */
-	if (enable_retry && unlikely(count > free_entries)) {
-		for (retry = 0; retry < burst_rx_retry_num; retry++) {
-			rte_delay_us(burst_rx_delay_time);
-			avail_idx = *((volatile uint16_t *)&vq->avail->idx);
-			free_entries = (avail_idx - *res_base_idx);
-			if (count <= free_entries)
-				break;
-		}
-	}
-
-	/*check that we have enough buffers*/
-	if (unlikely(count > free_entries))
-		count = free_entries;
-
-	if (unlikely(count == 0)) {
-		LOG_DEBUG(VHOST_DATA,
-			"(%"PRIu64") Fail in get_available_ring_index_zcp: "
-			"avail idx: %d, res base idx:%d, free entries:%d\n",
-			dev->device_fh, avail_idx,
-			*res_base_idx, free_entries);
-		return 0;
-	}
-
-	vq->last_used_idx_res = *res_base_idx + count;
-
-	return count;
-}
-
-/*
- * This function put descriptor back to used list.
- */
-static inline void __attribute__((always_inline))
-put_desc_to_used_list_zcp(struct vhost_virtqueue *vq, uint16_t desc_idx)
-{
-	uint16_t res_cur_idx = vq->last_used_idx;
-	vq->used->ring[res_cur_idx & (vq->size - 1)].id = (uint32_t)desc_idx;
-	vq->used->ring[res_cur_idx & (vq->size - 1)].len = 0;
-	rte_compiler_barrier();
-	*(volatile uint16_t *)&vq->used->idx += 1;
-	vq->last_used_idx += 1;
-
-	/* Kick the guest if necessary. */
-	if (!(vq->avail->flags & VRING_AVAIL_F_NO_INTERRUPT))
-		eventfd_write((int)vq->kickfd, 1);
-}
-
-/*
- * This function get available descriptor from vitio vring and un-attached mbuf
- * from vpool->ring, and then attach them together. It needs adjust the offset
- * for buff_addr and phys_addr accroding to PMD implementation, otherwise the
- * frame data may be put to wrong location in mbuf.
- */
-static inline void __attribute__((always_inline))
-attach_rxmbuf_zcp(struct virtio_net *dev)
-{
-	uint16_t res_base_idx, desc_idx;
-	uint64_t buff_addr, phys_addr;
-	struct vhost_virtqueue *vq;
-	struct vring_desc *desc;
-	struct rte_mbuf *mbuf = NULL;
-	struct vpool *vpool;
-	hpa_type addr_type;
-
-	vpool = &vpool_array[dev->vmdq_rx_q];
-	vq = dev->virtqueue[VIRTIO_RXQ];
-
-	do {
-		if (unlikely(get_available_ring_index_zcp(dev, &res_base_idx,
-				1) != 1))
-			return;
-		desc_idx = vq->avail->ring[(res_base_idx) & (vq->size - 1)];
-
-		desc = &vq->desc[desc_idx];
-		if (desc->flags & VRING_DESC_F_NEXT) {
-			desc = &vq->desc[desc->next];
-			buff_addr = gpa_to_vva(dev, desc->addr);
-			phys_addr = gpa_to_hpa(dev, desc->addr, desc->len,
-					&addr_type);
-		} else {
-			buff_addr = gpa_to_vva(dev,
-					desc->addr + vq->vhost_hlen);
-			phys_addr = gpa_to_hpa(dev,
-					desc->addr + vq->vhost_hlen,
-					desc->len, &addr_type);
-		}
-
-		if (unlikely(addr_type == PHYS_ADDR_INVALID)) {
-			RTE_LOG(ERR, VHOST_DATA, "(%"PRIu64") Invalid frame buffer"
-				" address found when attaching RX frame buffer"
-				" address!\n", dev->device_fh);
-			put_desc_to_used_list_zcp(vq, desc_idx);
-			continue;
-		}
-
-		/*
-		 * Check if the frame buffer address from guest crosses
-		 * sub-region or not.
-		 */
-		if (unlikely(addr_type == PHYS_ADDR_CROSS_SUBREG)) {
-			RTE_LOG(ERR, VHOST_DATA,
-				"(%"PRIu64") Frame buffer address cross "
-				"sub-regioin found when attaching RX frame "
-				"buffer address!\n",
-				dev->device_fh);
-			put_desc_to_used_list_zcp(vq, desc_idx);
-			continue;
-		}
-	} while (unlikely(phys_addr == 0));
-
-	rte_ring_sc_dequeue(vpool->ring, (void **)&mbuf);
-	if (unlikely(mbuf == NULL)) {
-		LOG_DEBUG(VHOST_DATA,
-			"(%"PRIu64") in attach_rxmbuf_zcp: "
-			"ring_sc_dequeue fail.\n",
-			dev->device_fh);
-		put_desc_to_used_list_zcp(vq, desc_idx);
-		return;
-	}
-
-	if (unlikely(vpool->buf_size > desc->len)) {
-		LOG_DEBUG(VHOST_DATA,
-			"(%"PRIu64") in attach_rxmbuf_zcp: frame buffer "
-			"length(%d) of descriptor idx: %d less than room "
-			"size required: %d\n",
-			dev->device_fh, desc->len, desc_idx, vpool->buf_size);
-		put_desc_to_used_list_zcp(vq, desc_idx);
-		rte_ring_sp_enqueue(vpool->ring, (void *)mbuf);
-		return;
-	}
-
-	mbuf->buf_addr = (void *)(uintptr_t)(buff_addr - RTE_PKTMBUF_HEADROOM);
-	mbuf->data_off = RTE_PKTMBUF_HEADROOM;
-	mbuf->buf_physaddr = phys_addr - RTE_PKTMBUF_HEADROOM;
-	mbuf->data_len = desc->len;
-	MBUF_HEADROOM_UINT32(mbuf) = (uint32_t)desc_idx;
-
-	LOG_DEBUG(VHOST_DATA,
-		"(%"PRIu64") in attach_rxmbuf_zcp: res base idx:%d, "
-		"descriptor idx:%d\n",
-		dev->device_fh, res_base_idx, desc_idx);
-
-	__rte_mbuf_raw_free(mbuf);
-
-	return;
-}
-
-/*
- * Detach an attched packet mbuf -
- *  - restore original mbuf address and length values.
- *  - reset pktmbuf data and data_len to their default values.
- *  All other fields of the given packet mbuf will be left intact.
- *
- * @param m
- *   The attached packet mbuf.
- */
-static inline void pktmbuf_detach_zcp(struct rte_mbuf *m)
-{
-	const struct rte_mempool *mp = m->pool;
-	void *buf = RTE_MBUF_TO_BADDR(m);
-	uint32_t buf_ofs;
-	uint32_t buf_len = mp->elt_size - sizeof(*m);
-	m->buf_physaddr = rte_mempool_virt2phy(mp, m) + sizeof(*m);
-
-	m->buf_addr = buf;
-	m->buf_len = (uint16_t)buf_len;
-
-	buf_ofs = (RTE_PKTMBUF_HEADROOM <= m->buf_len) ?
-			RTE_PKTMBUF_HEADROOM : m->buf_len;
-	m->data_off = buf_ofs;
-
-	m->data_len = 0;
-}
-
-/*
- * This function is called after packets have been transimited. It fetchs mbuf
- * from vpool->pool, detached it and put into vpool->ring. It also update the
- * used index and kick the guest if necessary.
- */
-static inline uint32_t __attribute__((always_inline))
-txmbuf_clean_zcp(struct virtio_net *dev, struct vpool *vpool)
-{
-	struct rte_mbuf *mbuf;
-	struct vhost_virtqueue *vq = dev->virtqueue[VIRTIO_TXQ];
-	uint32_t used_idx = vq->last_used_idx & (vq->size - 1);
-	uint32_t index = 0;
-	uint32_t mbuf_count = rte_mempool_count(vpool->pool);
-
-	LOG_DEBUG(VHOST_DATA,
-		"(%"PRIu64") in txmbuf_clean_zcp: mbuf count in mempool before "
-		"clean is: %d\n",
-		dev->device_fh, mbuf_count);
-	LOG_DEBUG(VHOST_DATA,
-		"(%"PRIu64") in txmbuf_clean_zcp: mbuf count in  ring before "
-		"clean  is : %d\n",
-		dev->device_fh, rte_ring_count(vpool->ring));
-
-	for (index = 0; index < mbuf_count; index++) {
-		mbuf = __rte_mbuf_raw_alloc(vpool->pool);
-		if (likely(RTE_MBUF_INDIRECT(mbuf)))
-			pktmbuf_detach_zcp(mbuf);
-		rte_ring_sp_enqueue(vpool->ring, mbuf);
-
-		/* Update used index buffer information. */
-		vq->used->ring[used_idx].id = MBUF_HEADROOM_UINT32(mbuf);
-		vq->used->ring[used_idx].len = 0;
-
-		used_idx = (used_idx + 1) & (vq->size - 1);
-	}
-
-	LOG_DEBUG(VHOST_DATA,
-		"(%"PRIu64") in txmbuf_clean_zcp: mbuf count in mempool after "
-		"clean is: %d\n",
-		dev->device_fh, rte_mempool_count(vpool->pool));
-	LOG_DEBUG(VHOST_DATA,
-		"(%"PRIu64") in txmbuf_clean_zcp: mbuf count in  ring after "
-		"clean  is : %d\n",
-		dev->device_fh, rte_ring_count(vpool->ring));
-	LOG_DEBUG(VHOST_DATA,
-		"(%"PRIu64") in txmbuf_clean_zcp: before updated "
-		"vq->last_used_idx:%d\n",
-		dev->device_fh, vq->last_used_idx);
-
-	vq->last_used_idx += mbuf_count;
-
-	LOG_DEBUG(VHOST_DATA,
-		"(%"PRIu64") in txmbuf_clean_zcp: after updated "
-		"vq->last_used_idx:%d\n",
-		dev->device_fh, vq->last_used_idx);
-
-	rte_compiler_barrier();
-
-	*(volatile uint16_t *)&vq->used->idx += mbuf_count;
-
-	/* Kick guest if required. */
-	if (!(vq->avail->flags & VRING_AVAIL_F_NO_INTERRUPT))
-		eventfd_write((int)vq->kickfd, 1);
-
-	return 0;
-}
-
-/*
- * This function is called when a virtio device is destroy.
- * It fetchs mbuf from vpool->pool, and detached it, and put into vpool->ring.
- */
-static void mbuf_destroy_zcp(struct vpool *vpool)
-{
-	struct rte_mbuf *mbuf = NULL;
-	uint32_t index, mbuf_count = rte_mempool_count(vpool->pool);
-
-	LOG_DEBUG(VHOST_CONFIG,
-		"in mbuf_destroy_zcp: mbuf count in mempool before "
-		"mbuf_destroy_zcp is: %d\n",
-		mbuf_count);
-	LOG_DEBUG(VHOST_CONFIG,
-		"in mbuf_destroy_zcp: mbuf count in  ring before "
-		"mbuf_destroy_zcp  is : %d\n",
-		rte_ring_count(vpool->ring));
-
-	for (index = 0; index < mbuf_count; index++) {
-		mbuf = __rte_mbuf_raw_alloc(vpool->pool);
-		if (likely(mbuf != NULL)) {
-			if (likely(RTE_MBUF_INDIRECT(mbuf)))
-				pktmbuf_detach_zcp(mbuf);
-			rte_ring_sp_enqueue(vpool->ring, (void *)mbuf);
-		}
-	}
-
-	LOG_DEBUG(VHOST_CONFIG,
-		"in mbuf_destroy_zcp: mbuf count in mempool after "
-		"mbuf_destroy_zcp is: %d\n",
-		rte_mempool_count(vpool->pool));
-	LOG_DEBUG(VHOST_CONFIG,
-		"in mbuf_destroy_zcp: mbuf count in ring after "
-		"mbuf_destroy_zcp is : %d\n",
-		rte_ring_count(vpool->ring));
-}
-
-/*
- * This function update the use flag and counter.
- */
-static inline uint32_t __attribute__((always_inline))
-virtio_dev_rx_zcp(struct virtio_net *dev, struct rte_mbuf **pkts,
-	uint32_t count)
-{
-	struct vhost_virtqueue *vq;
-	struct vring_desc *desc;
-	struct rte_mbuf *buff;
-	/* The virtio_hdr is initialised to 0. */
-	struct virtio_net_hdr_mrg_rxbuf virtio_hdr
-		= {{0, 0, 0, 0, 0, 0}, 0};
-	uint64_t buff_hdr_addr = 0;
-	uint32_t head[MAX_PKT_BURST], packet_len = 0;
-	uint32_t head_idx, packet_success = 0;
-	uint16_t res_cur_idx;
-
-	LOG_DEBUG(VHOST_DATA, "(%"PRIu64") virtio_dev_rx()\n", dev->device_fh);
-
-	if (count == 0)
-		return 0;
-
-	vq = dev->virtqueue[VIRTIO_RXQ];
-	count = (count > MAX_PKT_BURST) ? MAX_PKT_BURST : count;
-
-	res_cur_idx = vq->last_used_idx;
-	LOG_DEBUG(VHOST_DATA, "(%"PRIu64") Current Index %d| End Index %d\n",
-		dev->device_fh, res_cur_idx, res_cur_idx + count);
-
-	/* Retrieve all of the head indexes first to avoid caching issues. */
-	for (head_idx = 0; head_idx < count; head_idx++)
-		head[head_idx] = MBUF_HEADROOM_UINT32(pkts[head_idx]);
-
-	/*Prefetch descriptor index. */
-	rte_prefetch0(&vq->desc[head[packet_success]]);
-
-	while (packet_success != count) {
-		/* Get descriptor from available ring */
-		desc = &vq->desc[head[packet_success]];
-
-		buff = pkts[packet_success];
-		LOG_DEBUG(VHOST_DATA,
-			"(%"PRIu64") in dev_rx_zcp: update the used idx for "
-			"pkt[%d] descriptor idx: %d\n",
-			dev->device_fh, packet_success,
-			MBUF_HEADROOM_UINT32(buff));
-
-		PRINT_PACKET(dev,
-			(uintptr_t)(((uint64_t)(uintptr_t)buff->buf_addr)
-			+ RTE_PKTMBUF_HEADROOM),
-			rte_pktmbuf_data_len(buff), 0);
-
-		/* Buffer address translation for virtio header. */
-		buff_hdr_addr = gpa_to_vva(dev, desc->addr);
-		packet_len = rte_pktmbuf_data_len(buff) + vq->vhost_hlen;
-
-		/*
-		 * If the descriptors are chained the header and data are
-		 * placed in separate buffers.
-		 */
-		if (desc->flags & VRING_DESC_F_NEXT) {
-			desc->len = vq->vhost_hlen;
-			desc = &vq->desc[desc->next];
-			desc->len = rte_pktmbuf_data_len(buff);
-		} else {
-			desc->len = packet_len;
-		}
-
-		/* Update used ring with desc information */
-		vq->used->ring[res_cur_idx & (vq->size - 1)].id
-			= head[packet_success];
-		vq->used->ring[res_cur_idx & (vq->size - 1)].len
-			= packet_len;
-		res_cur_idx++;
-		packet_success++;
-
-		/* A header is required per buffer. */
-		rte_memcpy((void *)(uintptr_t)buff_hdr_addr,
-			(const void *)&virtio_hdr, vq->vhost_hlen);
-
-		PRINT_PACKET(dev, (uintptr_t)buff_hdr_addr, vq->vhost_hlen, 1);
-
-		if (likely(packet_success < count)) {
-			/* Prefetch descriptor index. */
-			rte_prefetch0(&vq->desc[head[packet_success]]);
-		}
-	}
-
-	rte_compiler_barrier();
-
-	LOG_DEBUG(VHOST_DATA,
-		"(%"PRIu64") in dev_rx_zcp: before update used idx: "
-		"vq.last_used_idx: %d, vq->used->idx: %d\n",
-		dev->device_fh, vq->last_used_idx, vq->used->idx);
-
-	*(volatile uint16_t *)&vq->used->idx += count;
-	vq->last_used_idx += count;
-
-	LOG_DEBUG(VHOST_DATA,
-		"(%"PRIu64") in dev_rx_zcp: after  update used idx: "
-		"vq.last_used_idx: %d, vq->used->idx: %d\n",
-		dev->device_fh, vq->last_used_idx, vq->used->idx);
-
-	/* Kick the guest if necessary. */
-	if (!(vq->avail->flags & VRING_AVAIL_F_NO_INTERRUPT))
-		eventfd_write((int)vq->kickfd, 1);
-
-	return count;
-}
-
-/*
- * This function routes the TX packet to the correct interface.
- * This may be a local device or the physical port.
- */
-static inline void __attribute__((always_inline))
-virtio_tx_route_zcp(struct virtio_net *dev, struct rte_mbuf *m,
-	uint32_t desc_idx, uint8_t need_copy)
-{
-	struct mbuf_table *tx_q;
-	struct rte_mbuf **m_table;
-	struct rte_mbuf *mbuf = NULL;
-	unsigned len, ret, offset = 0;
-	struct vpool *vpool;
-	struct virtio_net_data_ll *dev_ll = ll_root_used;
-	struct ether_hdr *pkt_hdr = rte_pktmbuf_mtod(m, struct ether_hdr *);
-	uint16_t vlan_tag = (uint16_t)vlan_tags[(uint16_t)dev->device_fh];
-
-	/*Add packet to the port tx queue*/
-	tx_q = &tx_queue_zcp[(uint16_t)dev->vmdq_rx_q];
-	len = tx_q->len;
-
-	/* Allocate an mbuf and populate the structure. */
-	vpool = &vpool_array[MAX_QUEUES + (uint16_t)dev->vmdq_rx_q];
-	rte_ring_sc_dequeue(vpool->ring, (void **)&mbuf);
-	if (unlikely(mbuf == NULL)) {
-		struct vhost_virtqueue *vq = dev->virtqueue[VIRTIO_TXQ];
-		RTE_LOG(ERR, VHOST_DATA,
-			"(%"PRIu64") Failed to allocate memory for mbuf.\n",
-			dev->device_fh);
-		put_desc_to_used_list_zcp(vq, desc_idx);
-		return;
-	}
-
-	if (vm2vm_mode == VM2VM_HARDWARE) {
-		/* Avoid using a vlan tag from any vm for external pkt, such as
-		 * vlan_tags[dev->device_fh], oterwise, it conflicts when pool
-		 * selection, MAC address determines it as an external pkt
-		 * which should go to network, while vlan tag determine it as
-		 * a vm2vm pkt should forward to another vm. Hardware confuse
-		 * such a ambiguous situation, so pkt will lost.
-		 */
-		vlan_tag = external_pkt_default_vlan_tag;
-		while (dev_ll != NULL) {
-			if (likely(dev_ll->dev->ready == DEVICE_RX) &&
-				ether_addr_cmp(&(pkt_hdr->d_addr),
-				&dev_ll->dev->mac_address)) {
-
-				/*
-				 * Drop the packet if the TX packet is destined
-				 * for the TX device.
-				 */
-				if (unlikely(dev_ll->dev->device_fh
-					== dev->device_fh)) {
-					LOG_DEBUG(VHOST_DATA,
-					"(%"PRIu64") TX: Source and destination"
-					"MAC addresses are the same. Dropping "
-					"packet.\n",
-					dev_ll->dev->device_fh);
-					MBUF_HEADROOM_UINT32(mbuf)
-						= (uint32_t)desc_idx;
-					__rte_mbuf_raw_free(mbuf);
-					return;
-				}
-
-				/*
-				 * Packet length offset 4 bytes for HW vlan
-				 * strip when L2 switch back.
-				 */
-				offset = 4;
-				vlan_tag =
-				(uint16_t)
-				vlan_tags[(uint16_t)dev_ll->dev->device_fh];
-
-				LOG_DEBUG(VHOST_DATA,
-				"(%"PRIu64") TX: pkt to local VM device id:"
-				"(%"PRIu64") vlan tag: %d.\n",
-				dev->device_fh, dev_ll->dev->device_fh,
-				vlan_tag);
-
-				break;
-			}
-			dev_ll = dev_ll->next;
-		}
-	}
-
-	mbuf->nb_segs = m->nb_segs;
-	mbuf->next = m->next;
-	mbuf->data_len = m->data_len + offset;
-	mbuf->pkt_len = mbuf->data_len;
-	if (unlikely(need_copy)) {
-		/* Copy the packet contents to the mbuf. */
-		rte_memcpy(rte_pktmbuf_mtod(mbuf, void *),
-			rte_pktmbuf_mtod(m, void *),
-			m->data_len);
-	} else {
-		mbuf->data_off = m->data_off;
-		mbuf->buf_physaddr = m->buf_physaddr;
-		mbuf->buf_addr = m->buf_addr;
-	}
-	mbuf->ol_flags = PKT_TX_VLAN_PKT;
-	mbuf->vlan_tci = vlan_tag;
-	mbuf->l2_len = sizeof(struct ether_hdr);
-	mbuf->l3_len = sizeof(struct ipv4_hdr);
-	MBUF_HEADROOM_UINT32(mbuf) = (uint32_t)desc_idx;
-
-	tx_q->m_table[len] = mbuf;
-	len++;
-
-	LOG_DEBUG(VHOST_DATA,
-		"(%"PRIu64") in tx_route_zcp: pkt: nb_seg: %d, next:%s\n",
-		dev->device_fh,
-		mbuf->nb_segs,
-		(mbuf->next == NULL) ? "null" : "non-null");
-
-	if (enable_stats) {
-		dev_statistics[dev->device_fh].tx_total++;
-		dev_statistics[dev->device_fh].tx++;
-	}
-
-	if (unlikely(len == MAX_PKT_BURST)) {
-		m_table = (struct rte_mbuf **)tx_q->m_table;
-		ret = rte_eth_tx_burst(ports[0],
-			(uint16_t)tx_q->txq_id, m_table, (uint16_t) len);
-
-		/*
-		 * Free any buffers not handled by TX and update
-		 * the port stats.
-		 */
-		if (unlikely(ret < len)) {
-			do {
-				rte_pktmbuf_free(m_table[ret]);
-			} while (++ret < len);
-		}
-
-		len = 0;
-		txmbuf_clean_zcp(dev, vpool);
-	}
-
-	tx_q->len = len;
-
-	return;
-}
-
-/*
- * This function TX all available packets in virtio TX queue for one
- * virtio-net device. If it is first packet, it learns MAC address and
- * setup VMDQ.
- */
-static inline void __attribute__((always_inline))
-virtio_dev_tx_zcp(struct virtio_net *dev)
-{
-	struct rte_mbuf m;
-	struct vhost_virtqueue *vq;
-	struct vring_desc *desc;
-	uint64_t buff_addr = 0, phys_addr;
-	uint32_t head[MAX_PKT_BURST];
-	uint32_t i;
-	uint16_t free_entries, packet_success = 0;
-	uint16_t avail_idx;
-	uint8_t need_copy = 0;
-	hpa_type addr_type;
-
-	vq = dev->virtqueue[VIRTIO_TXQ];
-	avail_idx =  *((volatile uint16_t *)&vq->avail->idx);
-
-	/* If there are no available buffers then return. */
-	if (vq->last_used_idx_res == avail_idx)
-		return;
-
-	LOG_DEBUG(VHOST_DATA, "(%"PRIu64") virtio_dev_tx()\n", dev->device_fh);
-
-	/* Prefetch available ring to retrieve head indexes. */
-	rte_prefetch0(&vq->avail->ring[vq->last_used_idx_res & (vq->size - 1)]);
-
-	/* Get the number of free entries in the ring */
-	free_entries = (avail_idx - vq->last_used_idx_res);
-
-	/* Limit to MAX_PKT_BURST. */
-	free_entries
-		= (free_entries > MAX_PKT_BURST) ? MAX_PKT_BURST : free_entries;
-
-	LOG_DEBUG(VHOST_DATA, "(%"PRIu64") Buffers available %d\n",
-		dev->device_fh, free_entries);
-
-	/* Retrieve all of the head indexes first to avoid caching issues. */
-	for (i = 0; i < free_entries; i++)
-		head[i]
-			= vq->avail->ring[(vq->last_used_idx_res + i)
-			& (vq->size - 1)];
-
-	vq->last_used_idx_res += free_entries;
-
-	/* Prefetch descriptor index. */
-	rte_prefetch0(&vq->desc[head[packet_success]]);
-	rte_prefetch0(&vq->used->ring[vq->last_used_idx & (vq->size - 1)]);
-
-	while (packet_success < free_entries) {
-		desc = &vq->desc[head[packet_success]];
-
-		/* Discard first buffer as it is the virtio header */
-		desc = &vq->desc[desc->next];
-
-		/* Buffer address translation. */
-		buff_addr = gpa_to_vva(dev, desc->addr);
-		phys_addr = gpa_to_hpa(dev, desc->addr, desc->len, &addr_type);
-
-		if (likely(packet_success < (free_entries - 1)))
-			/* Prefetch descriptor index. */
-			rte_prefetch0(&vq->desc[head[packet_success + 1]]);
-
-		if (unlikely(addr_type == PHYS_ADDR_INVALID)) {
-			RTE_LOG(ERR, VHOST_DATA,
-				"(%"PRIu64") Invalid frame buffer address found"
-				"when TX packets!\n",
-				dev->device_fh);
-			packet_success++;
-			continue;
-		}
-
-		/* Prefetch buffer address. */
-		rte_prefetch0((void *)(uintptr_t)buff_addr);
-
-		/*
-		 * Setup dummy mbuf. This is copied to a real mbuf if
-		 * transmitted out the physical port.
-		 */
-		m.data_len = desc->len;
-		m.nb_segs = 1;
-		m.next = NULL;
-		m.data_off = 0;
-		m.buf_addr = (void *)(uintptr_t)buff_addr;
-		m.buf_physaddr = phys_addr;
-
-		/*
-		 * Check if the frame buffer address from guest crosses
-		 * sub-region or not.
-		 */
-		if (unlikely(addr_type == PHYS_ADDR_CROSS_SUBREG)) {
-			RTE_LOG(ERR, VHOST_DATA,
-				"(%"PRIu64") Frame buffer address cross "
-				"sub-regioin found when attaching TX frame "
-				"buffer address!\n",
-				dev->device_fh);
-			need_copy = 1;
-		} else
-			need_copy = 0;
-
-		PRINT_PACKET(dev, (uintptr_t)buff_addr, desc->len, 0);
-
-		/*
-		 * If this is the first received packet we need to learn
-		 * the MAC and setup VMDQ
-		 */
-		if (unlikely(dev->ready == DEVICE_MAC_LEARNING)) {
-			if (dev->remove || (link_vmdq(dev, &m) == -1)) {
-				/*
-				 * Discard frame if device is scheduled for
-				 * removal or a duplicate MAC address is found.
-				 */
-				packet_success += free_entries;
-				vq->last_used_idx += packet_success;
-				break;
-			}
-		}
-
-		virtio_tx_route_zcp(dev, &m, head[packet_success], need_copy);
-		packet_success++;
-	}
-}
-
-/*
- * This function is called by each data core. It handles all RX/TX registered
- * with the core. For TX the specific lcore linked list is used. For RX, MAC
- * addresses are compared with all devices in the main linked list.
- */
-static int
-switch_worker_zcp(__attribute__((unused)) void *arg)
-{
-	struct virtio_net *dev = NULL;
-	struct rte_mbuf *pkts_burst[MAX_PKT_BURST];
-	struct virtio_net_data_ll *dev_ll;
-	struct mbuf_table *tx_q;
-	volatile struct lcore_ll_info *lcore_ll;
-	const uint64_t drain_tsc
-		= (rte_get_tsc_hz() + US_PER_S - 1) / US_PER_S
-		* BURST_TX_DRAIN_US;
-	uint64_t prev_tsc, diff_tsc, cur_tsc, ret_count = 0;
-	unsigned ret;
-	const uint16_t lcore_id = rte_lcore_id();
-	uint16_t count_in_ring, rx_count = 0;
-
-	RTE_LOG(INFO, VHOST_DATA, "Procesing on Core %u started\n", lcore_id);
-
-	lcore_ll = lcore_info[lcore_id].lcore_ll;
-	prev_tsc = 0;
-
-	while (1) {
-		cur_tsc = rte_rdtsc();
-
-		/* TX burst queue drain */
-		diff_tsc = cur_tsc - prev_tsc;
-		if (unlikely(diff_tsc > drain_tsc)) {
-			/*
-			 * Get mbuf from vpool.pool and detach mbuf and
-			 * put back into vpool.ring.
-			 */
-			dev_ll = lcore_ll->ll_root_used;
-			while ((dev_ll != NULL) && (dev_ll->dev != NULL)) {
-				/* Get virtio device ID */
-				dev = dev_ll->dev;
-
-				if (likely(!dev->remove)) {
-					tx_q = &tx_queue_zcp[(uint16_t)dev->vmdq_rx_q];
-					if (tx_q->len) {
-						LOG_DEBUG(VHOST_DATA,
-						"TX queue drained after timeout"
-						" with burst size %u\n",
-						tx_q->len);
-
-						/*
-						 * Tx any packets in the queue
-						 */
-						ret = rte_eth_tx_burst(
-							ports[0],
-							(uint16_t)tx_q->txq_id,
-							(struct rte_mbuf **)
-							tx_q->m_table,
-							(uint16_t)tx_q->len);
-						if (unlikely(ret < tx_q->len)) {
-							do {
-								rte_pktmbuf_free(
-									tx_q->m_table[ret]);
-							} while (++ret < tx_q->len);
-						}
-						tx_q->len = 0;
-
-						txmbuf_clean_zcp(dev,
-							&vpool_array[MAX_QUEUES+dev->vmdq_rx_q]);
-					}
-				}
-				dev_ll = dev_ll->next;
-			}
-			prev_tsc = cur_tsc;
-		}
-
-		rte_prefetch0(lcore_ll->ll_root_used);
-
-		/*
-		 * Inform the configuration core that we have exited the linked
-		 * list and that no devices are in use if requested.
-		 */
-		if (lcore_ll->dev_removal_flag == REQUEST_DEV_REMOVAL)
-			lcore_ll->dev_removal_flag = ACK_DEV_REMOVAL;
-
-		/* Process devices */
-		dev_ll = lcore_ll->ll_root_used;
-
-		while ((dev_ll != NULL) && (dev_ll->dev != NULL)) {
-			dev = dev_ll->dev;
-			if (unlikely(dev->remove)) {
-				dev_ll = dev_ll->next;
-				unlink_vmdq(dev);
-				dev->ready = DEVICE_SAFE_REMOVE;
-				continue;
-			}
-
-			if (likely(dev->ready == DEVICE_RX)) {
-				uint32_t index = dev->vmdq_rx_q;
-				uint16_t i;
-				count_in_ring
-				= rte_ring_count(vpool_array[index].ring);
-				uint16_t free_entries
-				= (uint16_t)get_available_ring_num_zcp(dev);
-
-				/*
-				 * Attach all mbufs in vpool.ring and put back
-				 * into vpool.pool.
-				 */
-				for (i = 0;
-				i < RTE_MIN(free_entries,
-				RTE_MIN(count_in_ring, MAX_PKT_BURST));
-				i++)
-					attach_rxmbuf_zcp(dev);
-
-				/* Handle guest RX */
-				rx_count = rte_eth_rx_burst(ports[0],
-					(uint16_t)dev->vmdq_rx_q, pkts_burst,
-					MAX_PKT_BURST);
-
-				if (rx_count) {
-					ret_count = virtio_dev_rx_zcp(dev,
-							pkts_burst, rx_count);
-					if (enable_stats) {
-						dev_statistics[dev->device_fh].rx_total
-							+= rx_count;
-						dev_statistics[dev->device_fh].rx
-							+= ret_count;
-					}
-					while (likely(rx_count)) {
-						rx_count--;
-						pktmbuf_detach_zcp(
-							pkts_burst[rx_count]);
-						rte_ring_sp_enqueue(
-							vpool_array[index].ring,
-							(void *)pkts_burst[rx_count]);
-					}
-				}
-			}
-
-			if (likely(!dev->remove))
-				/* Handle guest TX */
-				virtio_dev_tx_zcp(dev);
-
-			/* Move to the next device in the list */
-			dev_ll = dev_ll->next;
-		}
-	}
-
-	return 0;
-}
-
-
-/*
- * Add an entry to a used linked list. A free entry must first be found
- * in the free linked list using get_data_ll_free_entry();
- */
-static void
-add_data_ll_entry(struct virtio_net_data_ll **ll_root_addr,
-	struct virtio_net_data_ll *ll_dev)
-{
-	struct virtio_net_data_ll *ll = *ll_root_addr;
-
-	/* Set next as NULL and use a compiler barrier to avoid reordering. */
-	ll_dev->next = NULL;
-	rte_compiler_barrier();
-
-	/* If ll == NULL then this is the first device. */
-	if (ll) {
-		/* Increment to the tail of the linked list. */
-		while ((ll->next != NULL) )
-			ll = ll->next;
-
-		ll->next = ll_dev;
-	} else {
-		*ll_root_addr = ll_dev;
-	}
-}
-
-/*
- * Remove an entry from a used linked list. The entry must then be added to
- * the free linked list using put_data_ll_free_entry().
- */
-static void
-rm_data_ll_entry(struct virtio_net_data_ll **ll_root_addr,
-	struct virtio_net_data_ll *ll_dev,
-	struct virtio_net_data_ll *ll_dev_last)
-{
-	struct virtio_net_data_ll *ll = *ll_root_addr;
-
-	if (unlikely((ll == NULL) || (ll_dev == NULL)))
-		return;
-
-	if (ll_dev == ll)
-		*ll_root_addr = ll_dev->next;
-	else
-		if (likely(ll_dev_last != NULL))
-			ll_dev_last->next = ll_dev->next;
-		else
-			RTE_LOG(ERR, VHOST_CONFIG, "Remove entry form ll failed.\n");
-}
-
-/*
- * Find and return an entry from the free linked list.
- */
-static struct virtio_net_data_ll *
-get_data_ll_free_entry(struct virtio_net_data_ll **ll_root_addr)
-{
-	struct virtio_net_data_ll *ll_free = *ll_root_addr;
-	struct virtio_net_data_ll *ll_dev;
-
-	if (ll_free == NULL)
-		return NULL;
-
-	ll_dev = ll_free;
-	*ll_root_addr = ll_free->next;
-
-	return ll_dev;
-}
-
-/*
- * Place an entry back on to the free linked list.
- */
-static void
-put_data_ll_free_entry(struct virtio_net_data_ll **ll_root_addr,
-	struct virtio_net_data_ll *ll_dev)
-{
-	struct virtio_net_data_ll *ll_free = *ll_root_addr;
-
-	if (ll_dev == NULL)
-		return;
-
-	ll_dev->next = ll_free;
-	*ll_root_addr = ll_dev;
-}
-
-/*
- * Creates a linked list of a given size.
- */
-static struct virtio_net_data_ll *
-alloc_data_ll(uint32_t size)
-{
-	struct virtio_net_data_ll *ll_new;
-	uint32_t i;
-
-	/* Malloc and then chain the linked list. */
-	ll_new = malloc(size * sizeof(struct virtio_net_data_ll));
-	if (ll_new == NULL) {
-		RTE_LOG(ERR, VHOST_CONFIG, "Failed to allocate memory for ll_new.\n");
-		return NULL;
-	}
-
-	for (i = 0; i < size - 1; i++) {
-		ll_new[i].dev = NULL;
-		ll_new[i].next = &ll_new[i+1];
-	}
-	ll_new[i].next = NULL;
-
-	return (ll_new);
-}
-
-/*
- * Create the main linked list along with each individual cores linked list. A used and a free list
- * are created to manage entries.
- */
-static int
-init_data_ll (void)
-{
-	int lcore;
-
-	RTE_LCORE_FOREACH_SLAVE(lcore) {
-		lcore_info[lcore].lcore_ll = malloc(sizeof(struct lcore_ll_info));
-		if (lcore_info[lcore].lcore_ll == NULL) {
-			RTE_LOG(ERR, VHOST_CONFIG, "Failed to allocate memory for lcore_ll.\n");
-			return -1;
-		}
-
-		lcore_info[lcore].lcore_ll->device_num = 0;
-		lcore_info[lcore].lcore_ll->dev_removal_flag = ACK_DEV_REMOVAL;
-		lcore_info[lcore].lcore_ll->ll_root_used = NULL;
-		if (num_devices % num_switching_cores)
-			lcore_info[lcore].lcore_ll->ll_root_free = alloc_data_ll((num_devices / num_switching_cores) + 1);
-		else
-			lcore_info[lcore].lcore_ll->ll_root_free = alloc_data_ll(num_devices / num_switching_cores);
-	}
-
-	/* Allocate devices up to a maximum of MAX_DEVICES. */
-	ll_root_free = alloc_data_ll(MIN((num_devices), MAX_DEVICES));
-
-	return 0;
-}
-
-/*
- * Set virtqueue flags so that we do not receive interrupts.
- */
-static void
-set_irq_status (struct virtio_net *dev)
-{
-	dev->virtqueue[VIRTIO_RXQ]->used->flags = VRING_USED_F_NO_NOTIFY;
-	dev->virtqueue[VIRTIO_TXQ]->used->flags = VRING_USED_F_NO_NOTIFY;
-}
-
-/*
- * Remove a device from the specific data core linked list and from the main linked list. Synchonization
- * occurs through the use of the lcore dev_removal_flag. Device is made volatile here to avoid re-ordering
- * of dev->remove=1 which can cause an infinite loop in the rte_pause loop.
- */
-static void
-destroy_device (volatile struct virtio_net *dev)
-{
-	struct virtio_net_data_ll *ll_lcore_dev_cur;
-	struct virtio_net_data_ll *ll_main_dev_cur;
-	struct virtio_net_data_ll *ll_lcore_dev_last = NULL;
-	struct virtio_net_data_ll *ll_main_dev_last = NULL;
-	int lcore;
-
-	dev->flags &= ~VIRTIO_DEV_RUNNING;
-
-	/*set the remove flag. */
-	dev->remove = 1;
-
-	while(dev->ready != DEVICE_SAFE_REMOVE) {
-		rte_pause();
-	}
-
-	/* Search for entry to be removed from lcore ll */
-	ll_lcore_dev_cur = lcore_info[dev->coreid].lcore_ll->ll_root_used;
-	while (ll_lcore_dev_cur != NULL) {
-		if (ll_lcore_dev_cur->dev == dev) {
-			break;
-		} else {
-			ll_lcore_dev_last = ll_lcore_dev_cur;
-			ll_lcore_dev_cur = ll_lcore_dev_cur->next;
-		}
-	}
-
-	if (ll_lcore_dev_cur == NULL) {
-		RTE_LOG(ERR, VHOST_CONFIG,
-			"(%"PRIu64") Failed to find the dev to be destroy.\n",
-			dev->device_fh);
-		return;
-	}
-
-	/* Search for entry to be removed from main ll */
-	ll_main_dev_cur = ll_root_used;
-	ll_main_dev_last = NULL;
-	while (ll_main_dev_cur != NULL) {
-		if (ll_main_dev_cur->dev == dev) {
-			break;
-		} else {
-			ll_main_dev_last = ll_main_dev_cur;
-			ll_main_dev_cur = ll_main_dev_cur->next;
-		}
-	}
-
-	/* Remove entries from the lcore and main ll. */
-	rm_data_ll_entry(&lcore_info[ll_lcore_dev_cur->dev->coreid].lcore_ll->ll_root_used, ll_lcore_dev_cur, ll_lcore_dev_last);
-	rm_data_ll_entry(&ll_root_used, ll_main_dev_cur, ll_main_dev_last);
-
-	/* Set the dev_removal_flag on each lcore. */
-	RTE_LCORE_FOREACH_SLAVE(lcore) {
-		lcore_info[lcore].lcore_ll->dev_removal_flag = REQUEST_DEV_REMOVAL;
-	}
-
-	/*
-	 * Once each core has set the dev_removal_flag to ACK_DEV_REMOVAL we can be sure that
-	 * they can no longer access the device removed from the linked lists and that the devices
-	 * are no longer in use.
-	 */
-	RTE_LCORE_FOREACH_SLAVE(lcore) {
-		while (lcore_info[lcore].lcore_ll->dev_removal_flag != ACK_DEV_REMOVAL) {
-			rte_pause();
-		}
-	}
-
-	/* Add the entries back to the lcore and main free ll.*/
-	put_data_ll_free_entry(&lcore_info[ll_lcore_dev_cur->dev->coreid].lcore_ll->ll_root_free, ll_lcore_dev_cur);
-	put_data_ll_free_entry(&ll_root_free, ll_main_dev_cur);
-
-	/* Decrement number of device on the lcore. */
-	lcore_info[ll_lcore_dev_cur->dev->coreid].lcore_ll->device_num--;
-
-	RTE_LOG(INFO, VHOST_DATA, "(%"PRIu64") Device has been removed from data core\n", dev->device_fh);
-
-	if (zero_copy) {
-		struct vpool *vpool = &vpool_array[dev->vmdq_rx_q];
-
-		/* Stop the RX queue. */
-		if (rte_eth_dev_rx_queue_stop(ports[0], dev->vmdq_rx_q) != 0) {
-			LOG_DEBUG(VHOST_CONFIG,
-				"(%"PRIu64") In destroy_device: Failed to stop "
-				"rx queue:%d\n",
-				dev->device_fh,
-				dev->vmdq_rx_q);
-		}
-
-		LOG_DEBUG(VHOST_CONFIG,
-			"(%"PRIu64") in destroy_device: Start put mbuf in "
-			"mempool back to ring for RX queue: %d\n",
-			dev->device_fh, dev->vmdq_rx_q);
-
-		mbuf_destroy_zcp(vpool);
-
-		/* Stop the TX queue. */
-		if (rte_eth_dev_tx_queue_stop(ports[0], dev->vmdq_rx_q) != 0) {
-			LOG_DEBUG(VHOST_CONFIG,
-				"(%"PRIu64") In destroy_device: Failed to "
-				"stop tx queue:%d\n",
-				dev->device_fh, dev->vmdq_rx_q);
-		}
-
-		vpool = &vpool_array[dev->vmdq_rx_q + MAX_QUEUES];
-
-		LOG_DEBUG(VHOST_CONFIG,
-			"(%"PRIu64") destroy_device: Start put mbuf in mempool "
-			"back to ring for TX queue: %d, dev:(%"PRIu64")\n",
-			dev->device_fh, (dev->vmdq_rx_q + MAX_QUEUES),
-			dev->device_fh);
-
-		mbuf_destroy_zcp(vpool);
-	}
-
-}
-
-/*
- * A new device is added to a data core. First the device is added to the main linked list
- * and the allocated to a specific data core.
- */
-static int
-new_device (struct virtio_net *dev)
-{
-	struct virtio_net_data_ll *ll_dev;
-	int lcore, core_add = 0;
-	uint32_t device_num_min = num_devices;
-
-	/* Add device to main ll */
-	ll_dev = get_data_ll_free_entry(&ll_root_free);
-	if (ll_dev == NULL) {
-		RTE_LOG(INFO, VHOST_DATA, "(%"PRIu64") No free entry found in linked list. Device limit "
-			"of %d devices per core has been reached\n",
-			dev->device_fh, num_devices);
-		return -1;
-	}
-	ll_dev->dev = dev;
-	add_data_ll_entry(&ll_root_used, ll_dev);
-	ll_dev->dev->vmdq_rx_q
-		= ll_dev->dev->device_fh * (num_queues / num_devices);
-
-	if (zero_copy) {
-		uint32_t index = ll_dev->dev->vmdq_rx_q;
-		uint32_t count_in_ring, i;
-		struct mbuf_table *tx_q;
-
-		count_in_ring = rte_ring_count(vpool_array[index].ring);
-
-		LOG_DEBUG(VHOST_CONFIG,
-			"(%"PRIu64") in new_device: mbuf count in mempool "
-			"before attach is: %d\n",
-			dev->device_fh,
-			rte_mempool_count(vpool_array[index].pool));
-		LOG_DEBUG(VHOST_CONFIG,
-			"(%"PRIu64") in new_device: mbuf count in  ring "
-			"before attach  is : %d\n",
-			dev->device_fh, count_in_ring);
-
-		/*
-		 * Attach all mbufs in vpool.ring and put back intovpool.pool.
-		 */
-		for (i = 0; i < count_in_ring; i++)
-			attach_rxmbuf_zcp(dev);
-
-		LOG_DEBUG(VHOST_CONFIG, "(%"PRIu64") in new_device: mbuf count in "
-			"mempool after attach is: %d\n",
-			dev->device_fh,
-			rte_mempool_count(vpool_array[index].pool));
-		LOG_DEBUG(VHOST_CONFIG, "(%"PRIu64") in new_device: mbuf count in "
-			"ring after attach  is : %d\n",
-			dev->device_fh,
-			rte_ring_count(vpool_array[index].ring));
-
-		tx_q = &tx_queue_zcp[(uint16_t)dev->vmdq_rx_q];
-		tx_q->txq_id = dev->vmdq_rx_q;
-
-		if (rte_eth_dev_tx_queue_start(ports[0], dev->vmdq_rx_q) != 0) {
-			struct vpool *vpool = &vpool_array[dev->vmdq_rx_q];
-
-			LOG_DEBUG(VHOST_CONFIG,
-				"(%"PRIu64") In new_device: Failed to start "
-				"tx queue:%d\n",
-				dev->device_fh, dev->vmdq_rx_q);
-
-			mbuf_destroy_zcp(vpool);
-			return -1;
-		}
-
-		if (rte_eth_dev_rx_queue_start(ports[0], dev->vmdq_rx_q) != 0) {
-			struct vpool *vpool = &vpool_array[dev->vmdq_rx_q];
-
-			LOG_DEBUG(VHOST_CONFIG,
-				"(%"PRIu64") In new_device: Failed to start "
-				"rx queue:%d\n",
-				dev->device_fh, dev->vmdq_rx_q);
-
-			/* Stop the TX queue. */
-			if (rte_eth_dev_tx_queue_stop(ports[0],
-				dev->vmdq_rx_q) != 0) {
-				LOG_DEBUG(VHOST_CONFIG,
-					"(%"PRIu64") In new_device: Failed to "
-					"stop tx queue:%d\n",
-					dev->device_fh, dev->vmdq_rx_q);
-			}
-
-			mbuf_destroy_zcp(vpool);
-			return -1;
-		}
-
-	}
-
-	/*reset ready flag*/
-	dev->ready = DEVICE_MAC_LEARNING;
-	dev->remove = 0;
-
-	/* Find a suitable lcore to add the device. */
-	RTE_LCORE_FOREACH_SLAVE(lcore) {
-		if (lcore_info[lcore].lcore_ll->device_num < device_num_min) {
-			device_num_min = lcore_info[lcore].lcore_ll->device_num;
-			core_add = lcore;
-		}
-	}
-	/* Add device to lcore ll */
-	ll_dev->dev->coreid = core_add;
-	ll_dev = get_data_ll_free_entry(&lcore_info[ll_dev->dev->coreid].lcore_ll->ll_root_free);
-	if (ll_dev == NULL) {
-		RTE_LOG(INFO, VHOST_DATA, "(%"PRIu64") Failed to add device to data core\n", dev->device_fh);
-		dev->ready = DEVICE_SAFE_REMOVE;
-		destroy_device(dev);
-		return -1;
-	}
-	ll_dev->dev = dev;
-	add_data_ll_entry(&lcore_info[ll_dev->dev->coreid].lcore_ll->ll_root_used, ll_dev);
-
-	/* Initialize device stats */
-	memset(&dev_statistics[dev->device_fh], 0, sizeof(struct device_statistics));
-
-	/* Disable notifications. */
-	set_irq_status(dev);
-	lcore_info[ll_dev->dev->coreid].lcore_ll->device_num++;
-	dev->flags |= VIRTIO_DEV_RUNNING;
-
-	RTE_LOG(INFO, VHOST_DATA, "(%"PRIu64") Device has been added to data core %d\n", dev->device_fh, dev->coreid);
-
-	return 0;
-}
-
-/*
- * These callback allow devices to be added to the data core when configuration
- * has been fully complete.
- */
-static const struct virtio_net_device_ops virtio_net_device_ops =
-{
-	.new_device =  new_device,
-	.destroy_device = destroy_device,
-};
-
-/*
- * This is a thread will wake up after a period to print stats if the user has
- * enabled them.
- */
-static void
-print_stats(void)
-{
-	struct virtio_net_data_ll *dev_ll;
-	uint64_t tx_dropped, rx_dropped;
-	uint64_t tx, tx_total, rx, rx_total;
-	uint32_t device_fh;
-	const char clr[] = { 27, '[', '2', 'J', '\0' };
-	const char top_left[] = { 27, '[', '1', ';', '1', 'H','\0' };
-
-	while(1) {
-		sleep(enable_stats);
-
-		/* Clear screen and move to top left */
-		printf("%s%s", clr, top_left);
-
-		printf("\nDevice statistics ====================================");
-
-		dev_ll = ll_root_used;
-		while (dev_ll != NULL) {
-			device_fh = (uint32_t)dev_ll->dev->device_fh;
-			tx_total = dev_statistics[device_fh].tx_total;
-			tx = dev_statistics[device_fh].tx;
-			tx_dropped = tx_total - tx;
-			if (zero_copy == 0) {
-				rx_total = rte_atomic64_read(
-					&dev_statistics[device_fh].rx_total_atomic);
-				rx = rte_atomic64_read(
-					&dev_statistics[device_fh].rx_atomic);
-			} else {
-				rx_total = dev_statistics[device_fh].rx_total;
-				rx = dev_statistics[device_fh].rx;
-			}
-			rx_dropped = rx_total - rx;
-
-			printf("\nStatistics for device %"PRIu32" ------------------------------"
-					"\nTX total: 		%"PRIu64""
-					"\nTX dropped: 		%"PRIu64""
-					"\nTX successful: 		%"PRIu64""
-					"\nRX total: 		%"PRIu64""
-					"\nRX dropped: 		%"PRIu64""
-					"\nRX successful: 		%"PRIu64"",
-					device_fh,
-					tx_total,
-					tx_dropped,
-					tx,
-					rx_total,
-					rx_dropped,
-					rx);
-
-			dev_ll = dev_ll->next;
-		}
-		printf("\n======================================================\n");
-	}
-}
-
-static void
-setup_mempool_tbl(int socket, uint32_t index, char *pool_name,
-	char *ring_name, uint32_t nb_mbuf)
-{
-	uint16_t roomsize = VIRTIO_DESCRIPTOR_LEN_ZCP + RTE_PKTMBUF_HEADROOM;
-	vpool_array[index].pool
-		= rte_mempool_create(pool_name, nb_mbuf, MBUF_SIZE_ZCP,
-		MBUF_CACHE_SIZE_ZCP, sizeof(struct rte_pktmbuf_pool_private),
-		rte_pktmbuf_pool_init, (void *)(uintptr_t)roomsize,
-		rte_pktmbuf_init, NULL, socket, 0);
-	if (vpool_array[index].pool != NULL) {
-		vpool_array[index].ring
-			= rte_ring_create(ring_name,
-				rte_align32pow2(nb_mbuf + 1),
-				socket, RING_F_SP_ENQ | RING_F_SC_DEQ);
-		if (likely(vpool_array[index].ring != NULL)) {
-			LOG_DEBUG(VHOST_CONFIG,
-				"in setup_mempool_tbl: mbuf count in "
-				"mempool is: %d\n",
-				rte_mempool_count(vpool_array[index].pool));
-			LOG_DEBUG(VHOST_CONFIG,
-				"in setup_mempool_tbl: mbuf count in "
-				"ring   is: %d\n",
-				rte_ring_count(vpool_array[index].ring));
-		} else {
-			rte_exit(EXIT_FAILURE, "ring_create(%s) failed",
-				ring_name);
-		}
-
-		/* Need consider head room. */
-		vpool_array[index].buf_size = roomsize - RTE_PKTMBUF_HEADROOM;
-	} else {
-		rte_exit(EXIT_FAILURE, "mempool_create(%s) failed", pool_name);
-	}
-}
-
-
-/*
- * Main function, does initialisation and calls the per-lcore functions. The CUSE
- * device is also registered here to handle the IOCTLs.
- */
-int
-MAIN(int argc, char *argv[])
-{
-	struct rte_mempool *mbuf_pool = NULL;
-	unsigned lcore_id, core_id = 0;
-	unsigned nb_ports, valid_num_ports;
-	int ret;
-	uint8_t portid, queue_id = 0;
-	static pthread_t tid;
-
-	/* init EAL */
-	ret = rte_eal_init(argc, argv);
-	if (ret < 0)
-		rte_exit(EXIT_FAILURE, "Error with EAL initialization\n");
-	argc -= ret;
-	argv += ret;
-
-	/* parse app arguments */
-	ret = us_vhost_parse_args(argc, argv);
-	if (ret < 0)
-		rte_exit(EXIT_FAILURE, "Invalid argument\n");
-
-	if (rte_eal_pci_probe() != 0)
-		rte_exit(EXIT_FAILURE, "Error with NIC driver initialization\n");
-
-	for (lcore_id = 0; lcore_id < RTE_MAX_LCORE; lcore_id ++)
-		if (rte_lcore_is_enabled(lcore_id))
-			lcore_ids[core_id ++] = lcore_id;
-
-	if (rte_lcore_count() > RTE_MAX_LCORE)
-		rte_exit(EXIT_FAILURE,"Not enough cores\n");
-
-	/*set the number of swithcing cores available*/
-	num_switching_cores = rte_lcore_count()-1;
-
-	/* Get the number of physical ports. */
-	nb_ports = rte_eth_dev_count();
-	if (nb_ports > RTE_MAX_ETHPORTS)
-		nb_ports = RTE_MAX_ETHPORTS;
-
-	/*
-	 * Update the global var NUM_PORTS and global array PORTS
-	 * and get value of var VALID_NUM_PORTS according to system ports number
-	 */
-	valid_num_ports = check_ports_num(nb_ports);
-
-	if ((valid_num_ports ==  0) || (valid_num_ports > MAX_SUP_PORTS)) {
-		RTE_LOG(INFO, VHOST_PORT, "Current enabled port number is %u,"
-			"but only %u port can be enabled\n",num_ports, MAX_SUP_PORTS);
-		return -1;
-	}
-
-	if (zero_copy == 0) {
-		/* Create the mbuf pool. */
-		mbuf_pool = rte_mempool_create(
-				"MBUF_POOL",
-				NUM_MBUFS_PER_PORT
-				* valid_num_ports,
-				MBUF_SIZE, MBUF_CACHE_SIZE,
-				sizeof(struct rte_pktmbuf_pool_private),
-				rte_pktmbuf_pool_init, NULL,
-				rte_pktmbuf_init, NULL,
-				rte_socket_id(), 0);
-		if (mbuf_pool == NULL)
-			rte_exit(EXIT_FAILURE, "Cannot create mbuf pool\n");
-
-		for (queue_id = 0; queue_id < MAX_QUEUES + 1; queue_id++)
-			vpool_array[queue_id].pool = mbuf_pool;
-
-		if (vm2vm_mode == VM2VM_HARDWARE) {
-			/* Enable VT loop back to let L2 switch to do it. */
-			vmdq_conf_default.rx_adv_conf.vmdq_rx_conf.enable_loop_back = 1;
-			LOG_DEBUG(VHOST_CONFIG,
-				"Enable loop back for L2 switch in vmdq.\n");
-		}
-	} else {
-		uint32_t nb_mbuf;
-		char pool_name[RTE_MEMPOOL_NAMESIZE];
-		char ring_name[RTE_MEMPOOL_NAMESIZE];
-
-		rx_conf_default.start_rx_per_q = (uint8_t)zero_copy;
-		rx_conf_default.rx_drop_en = 0;
-		tx_conf_default.start_tx_per_q = (uint8_t)zero_copy;
-		nb_mbuf = num_rx_descriptor
-			+ num_switching_cores * MBUF_CACHE_SIZE_ZCP
-			+ num_switching_cores * MAX_PKT_BURST;
-
-		for (queue_id = 0; queue_id < MAX_QUEUES; queue_id++) {
-			snprintf(pool_name, sizeof(pool_name),
-				"rxmbuf_pool_%u", queue_id);
-			snprintf(ring_name, sizeof(ring_name),
-				"rxmbuf_ring_%u", queue_id);
-			setup_mempool_tbl(rte_socket_id(), queue_id,
-				pool_name, ring_name, nb_mbuf);
-		}
-
-		nb_mbuf = num_tx_descriptor
-				+ num_switching_cores * MBUF_CACHE_SIZE_ZCP
-				+ num_switching_cores * MAX_PKT_BURST;
-
-		for (queue_id = 0; queue_id < MAX_QUEUES; queue_id++) {
-			snprintf(pool_name, sizeof(pool_name),
-				"txmbuf_pool_%u", queue_id);
-			snprintf(ring_name, sizeof(ring_name),
-				"txmbuf_ring_%u", queue_id);
-			setup_mempool_tbl(rte_socket_id(),
-				(queue_id + MAX_QUEUES),
-				pool_name, ring_name, nb_mbuf);
-		}
-
-		if (vm2vm_mode == VM2VM_HARDWARE) {
-			/* Enable VT loop back to let L2 switch to do it. */
-			vmdq_conf_default.rx_adv_conf.vmdq_rx_conf.enable_loop_back = 1;
-			LOG_DEBUG(VHOST_CONFIG,
-				"Enable loop back for L2 switch in vmdq.\n");
-		}
-	}
-	/* Set log level. */
-	rte_set_log_level(LOG_LEVEL);
-
-	/* initialize all ports */
-	for (portid = 0; portid < nb_ports; portid++) {
-		/* skip ports that are not enabled */
-		if ((enabled_port_mask & (1 << portid)) == 0) {
-			RTE_LOG(INFO, VHOST_PORT,
-				"Skipping disabled port %d\n", portid);
-			continue;
-		}
-		if (port_init(portid) != 0)
-			rte_exit(EXIT_FAILURE,
-				"Cannot initialize network ports\n");
-	}
-
-	/* Initialise all linked lists. */
-	if (init_data_ll() == -1)
-		rte_exit(EXIT_FAILURE, "Failed to initialize linked list\n");
-
-	/* Initialize device stats */
-	memset(&dev_statistics, 0, sizeof(dev_statistics));
-
-	/* Enable stats if the user option is set. */
-	if (enable_stats)
-		pthread_create(&tid, NULL, (void*)print_stats, NULL );
-
-	/* Launch all data cores. */
-	if (zero_copy == 0) {
-		RTE_LCORE_FOREACH_SLAVE(lcore_id) {
-			rte_eal_remote_launch(switch_worker,
-				mbuf_pool, lcore_id);
-		}
-	} else {
-		uint32_t count_in_mempool, index, i;
-		for (index = 0; index < 2*MAX_QUEUES; index++) {
-			/* For all RX and TX queues. */
-			count_in_mempool
-				= rte_mempool_count(vpool_array[index].pool);
-
-			/*
-			 * Transfer all un-attached mbufs from vpool.pool
-			 * to vpoo.ring.
-			 */
-			for (i = 0; i < count_in_mempool; i++) {
-				struct rte_mbuf *mbuf
-					= __rte_mbuf_raw_alloc(
-						vpool_array[index].pool);
-				rte_ring_sp_enqueue(vpool_array[index].ring,
-						(void *)mbuf);
-			}
-
-			LOG_DEBUG(VHOST_CONFIG,
-				"in MAIN: mbuf count in mempool at initial "
-				"is: %d\n", count_in_mempool);
-			LOG_DEBUG(VHOST_CONFIG,
-				"in MAIN: mbuf count in  ring at initial  is :"
-				" %d\n",
-				rte_ring_count(vpool_array[index].ring));
-		}
-
-		RTE_LCORE_FOREACH_SLAVE(lcore_id)
-			rte_eal_remote_launch(switch_worker_zcp, NULL,
-				lcore_id);
-	}
-
-	/* Register CUSE device to handle IOCTLs. */
-	ret = register_cuse_device((char*)&dev_basename, dev_index, get_virtio_net_callbacks());
-	if (ret != 0)
-		rte_exit(EXIT_FAILURE,"CUSE device setup failure.\n");
-
-	init_virtio_net(&virtio_net_device_ops);
-
-	/* Start CUSE session. */
-	start_cuse_session_loop();
-	return 0;
-
-}
-
diff --git a/examples/vhost/main.h b/examples/vhost/main.h
deleted file mode 100644
index c15d938..0000000
--- a/examples/vhost/main.h
+++ /dev/null
@@ -1,86 +0,0 @@
-/*-
- *   BSD LICENSE
- *
- *   Copyright(c) 2010-2014 Intel Corporation. All rights reserved.
- *   All rights reserved.
- *
- *   Redistribution and use in source and binary forms, with or without
- *   modification, are permitted provided that the following conditions
- *   are met:
- *
- *     * Redistributions of source code must retain the above copyright
- *       notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above copyright
- *       notice, this list of conditions and the following disclaimer in
- *       the documentation and/or other materials provided with the
- *       distribution.
- *     * Neither the name of Intel Corporation nor the names of its
- *       contributors may be used to endorse or promote products derived
- *       from this software without specific prior written permission.
- *
- *   THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- *   "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- *   LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- *   A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- *   OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- *   SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- *   LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- *   DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- *   THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- *   (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- *   OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
- */
-
-#ifndef _MAIN_H_
-#define _MAIN_H_
-
-#ifdef RTE_EXEC_ENV_BAREMETAL
-#define MAIN _main
-#else
-#define MAIN main
-#endif
-
-//#define DEBUG
-
-#ifdef DEBUG
-#define LOG_LEVEL RTE_LOG_DEBUG
-#define LOG_DEBUG(log_type, fmt, args...) do {	\
-	RTE_LOG(DEBUG, log_type, fmt, ##args);		\
-} while (0)
-#else
-#define LOG_LEVEL RTE_LOG_INFO
-#define LOG_DEBUG(log_type, fmt, args...) do{} while(0)
-#endif
-
-/* Macros for printing using RTE_LOG */
-#define RTE_LOGTYPE_VHOST_CONFIG RTE_LOGTYPE_USER1
-#define RTE_LOGTYPE_VHOST_DATA   RTE_LOGTYPE_USER2
-#define RTE_LOGTYPE_VHOST_PORT   RTE_LOGTYPE_USER3
-
-/*
- * Device linked list structure for data path.
- */
-struct virtio_net_data_ll
-{
-	struct virtio_net			*dev;	/* Pointer to device created by configuration core. */
-	struct virtio_net_data_ll	*next;  /* Pointer to next device in linked list. */
-};
-
-/*
- * Structure containing data core specific information.
- */
-struct lcore_ll_info
-{
-	struct virtio_net_data_ll	*ll_root_free; 		/* Pointer to head in free linked list. */
-	struct virtio_net_data_ll	*ll_root_used;		/* Pointer to head of used linked list. */
-	uint32_t 					device_num;			/* Number of devices on lcore. */
-	volatile uint8_t			dev_removal_flag;	/* Flag to synchronize device removal. */
-};
-
-struct lcore_info
-{
-	struct lcore_ll_info	*lcore_ll;	/* Pointer to data core specific lcore_ll_info struct */
-};
-
-int MAIN(int argc, char **argv);
-#endif /* _MAIN_H_ */
diff --git a/examples/vhost/vhost-net-cdev.c b/examples/vhost/vhost-net-cdev.c
deleted file mode 100644
index 8cf806a..0000000
--- a/examples/vhost/vhost-net-cdev.c
+++ /dev/null
@@ -1,367 +0,0 @@
-/*-
- *   BSD LICENSE
- *
- *   Copyright(c) 2010-2014 Intel Corporation. All rights reserved.
- *   All rights reserved.
- *
- *   Redistribution and use in source and binary forms, with or without
- *   modification, are permitted provided that the following conditions
- *   are met:
- *
- *     * Redistributions of source code must retain the above copyright
- *       notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above copyright
- *       notice, this list of conditions and the following disclaimer in
- *       the documentation and/or other materials provided with the
- *       distribution.
- *     * Neither the name of Intel Corporation nor the names of its
- *       contributors may be used to endorse or promote products derived
- *       from this software without specific prior written permission.
- *
- *   THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- *   "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- *   LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- *   A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- *   OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- *   SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- *   LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- *   DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- *   THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- *   (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- *   OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
- */
-
-#include <errno.h>
-#include <fuse/cuse_lowlevel.h>
-#include <linux/limits.h>
-#include <linux/vhost.h>
-#include <stdint.h>
-#include <string.h>
-#include <unistd.h>
-
-#include <rte_ethdev.h>
-#include <rte_log.h>
-#include <rte_string_fns.h>
-
-#include "main.h"
-#include "vhost-net-cdev.h"
-
-#define FUSE_OPT_DUMMY 		"\0\0"
-#define FUSE_OPT_FORE 		"-f\0\0"
-#define FUSE_OPT_NOMULTI 	"-s\0\0"
-
-const uint32_t	default_major = 231;
-const uint32_t	default_minor = 1;
-const char		cuse_device_name[]	= "/dev/cuse";
-const char		default_cdev[] = "vhost-net";
-
-static struct fuse_session			*session;
-static struct vhost_net_device_ops	const *ops;
-
-/*
- * Returns vhost_device_ctx from given fuse_req_t. The index is populated later when
- * the device is added to the device linked list.
- */
-static struct vhost_device_ctx
-fuse_req_to_vhost_ctx(fuse_req_t req, struct fuse_file_info *fi)
-{
-	struct vhost_device_ctx ctx;
-	struct fuse_ctx const *const req_ctx = fuse_req_ctx(req);
-
-	ctx.pid = req_ctx->pid;
-	ctx.fh = fi->fh;
-
-	return ctx;
-}
-
-/*
- * When the device is created in QEMU it gets initialised here and added to the device linked list.
- */
-static void
-vhost_net_open(fuse_req_t req, struct fuse_file_info *fi)
-{
-	struct vhost_device_ctx ctx = fuse_req_to_vhost_ctx(req, fi);
-	int err = 0;
-
-	err = ops->new_device(ctx);
-	if (err == -1) {
-		fuse_reply_err(req, EPERM);
-		return;
-	}
-
-	fi->fh = err;
-
-	RTE_LOG(INFO, VHOST_CONFIG, "(%"PRIu64") Device configuration started\n", fi->fh);
-	fuse_reply_open(req, fi);
-}
-
-/*
- * When QEMU is shutdown or killed the device gets released.
- */
-static void
-vhost_net_release(fuse_req_t req, struct fuse_file_info *fi)
-{
-	int err = 0;
-	struct vhost_device_ctx ctx = fuse_req_to_vhost_ctx(req, fi);
-
-	ops->destroy_device(ctx);
-	RTE_LOG(INFO, VHOST_CONFIG, "(%"PRIu64") Device released\n", ctx.fh);
-	fuse_reply_err(req, err);
-}
-
-/*
- * Boilerplate code for CUSE IOCTL
- * Implicit arguments: ctx, req, result.
- */
-#define VHOST_IOCTL(func) do {								\
-	result = (func)(ctx);									\
-	fuse_reply_ioctl(req, result, NULL, 0);					\
-} while(0)													\
-
-/*
- * Boilerplate IOCTL RETRY
- * Implicit arguments: req.
- */
-#define VHOST_IOCTL_RETRY(size_r, size_w) do {									\
-	struct iovec iov_r = { arg, (size_r) };										\
-	struct iovec iov_w = { arg, (size_w) };										\
-	fuse_reply_ioctl_retry(req, &iov_r, (size_r)?1:0, &iov_w, (size_w)?1:0);	\
-} while(0)																		\
-
-/*
- * Boilerplate code for CUSE Read IOCTL
- * Implicit arguments: ctx, req, result, in_bufsz, in_buf.
- */
-#define VHOST_IOCTL_R(type, var, func) do {				\
-	if (!in_bufsz) {									\
-		VHOST_IOCTL_RETRY(sizeof(type), 0);				\
-	} else {											\
-		(var) = *(const type * ) in_buf;				\
-		result = func(ctx, &(var));						\
-		fuse_reply_ioctl(req, result, NULL, 0);			\
-	}													\
-} while(0)												\
-
-/*
- *	Boilerplate code for CUSE Write IOCTL
- * Implicit arguments: ctx, req, result, out_bufsz.
- */
-#define	VHOST_IOCTL_W(type, var, func) do {						\
-	if (!out_bufsz) {											\
-		VHOST_IOCTL_RETRY(0, sizeof(type));						\
-	} else {													\
-		result = (func)(ctx, &(var));							\
-		fuse_reply_ioctl(req, result, &(var), sizeof(type));	\
-	}															\
-} while(0)														\
-
-/*
- * Boilerplate code for CUSE Read/Write IOCTL
- * Implicit arguments: ctx, req, result, in_bufsz, in_buf.
- */
-#define VHOST_IOCTL_RW(type1, var1, type2, var2, func) do {			\
-	if (!in_bufsz) {												\
-		VHOST_IOCTL_RETRY(sizeof(type1), sizeof(type2));			\
-	} else {														\
-		(var1) = *(const type1* ) (in_buf);							\
-		result = (func)(ctx, (var1), &(var2));						\
-		fuse_reply_ioctl(req, result, &(var2), sizeof(type2));		\
-	}																\
-} while(0)															\
-
-/*
- * The IOCTLs are handled using CUSE/FUSE in userspace. Depending on
- * the type of IOCTL a buffer is requested to read or to write. This
- * request is handled by FUSE and the buffer is then given to CUSE.
- */
-static void
-vhost_net_ioctl(fuse_req_t req, int cmd, void *arg,
-		struct fuse_file_info *fi, __rte_unused unsigned flags,
-		const void *in_buf, size_t in_bufsz, size_t out_bufsz)
-{
-	struct vhost_device_ctx ctx = fuse_req_to_vhost_ctx(req, fi);
-	struct vhost_vring_file file;
-	struct vhost_vring_state state;
-	struct vhost_vring_addr addr;
-	uint64_t features;
-	uint32_t index;
-	int result = 0;
-
-	switch(cmd)
-	{
-		case VHOST_NET_SET_BACKEND:
-			LOG_DEBUG(VHOST_CONFIG, "(%"PRIu64") IOCTL: VHOST_NET_SET_BACKEND\n", ctx.fh);
-			VHOST_IOCTL_R(struct vhost_vring_file, file, ops->set_backend);
-			break;
-
-		case VHOST_GET_FEATURES:
-			LOG_DEBUG(VHOST_CONFIG, "(%"PRIu64") IOCTL: VHOST_GET_FEATURES\n", ctx.fh);
-			VHOST_IOCTL_W(uint64_t, features, ops->get_features);
-			break;
-
-		case VHOST_SET_FEATURES:
-			LOG_DEBUG(VHOST_CONFIG, "(%"PRIu64") IOCTL: VHOST_SET_FEATURES\n", ctx.fh);
-			VHOST_IOCTL_R(uint64_t, features, ops->set_features);
-			break;
-
-		case VHOST_RESET_OWNER:
-			LOG_DEBUG(VHOST_CONFIG, "(%"PRIu64") IOCTL: VHOST_RESET_OWNER\n", ctx.fh);
-			VHOST_IOCTL(ops->reset_owner);
-			break;
-
-		case VHOST_SET_OWNER:
-			LOG_DEBUG(VHOST_CONFIG, "(%"PRIu64") IOCTL: VHOST_SET_OWNER\n", ctx.fh);
-			VHOST_IOCTL(ops->set_owner);
-			break;
-
-		case VHOST_SET_MEM_TABLE:
-			LOG_DEBUG(VHOST_CONFIG, "(%"PRIu64") IOCTL: VHOST_SET_MEM_TABLE\n", ctx.fh);
-			static struct vhost_memory mem_temp;
-
-			switch(in_bufsz){
-				case 0:
-					VHOST_IOCTL_RETRY(sizeof(struct vhost_memory), 0);
-					break;
-
-				case sizeof(struct vhost_memory):
-					mem_temp = *(const struct vhost_memory *) in_buf;
-
-					if (mem_temp.nregions > 0) {
-						VHOST_IOCTL_RETRY(sizeof(struct vhost_memory) + (sizeof(struct vhost_memory_region) * mem_temp.nregions), 0);
-					} else {
-						result = -1;
-						fuse_reply_ioctl(req, result, NULL, 0);
-					}
-					break;
-
-				default:
-					result = ops->set_mem_table(ctx, in_buf, mem_temp.nregions);
-					if (result)
-						fuse_reply_err(req, EINVAL);
-					else
-						fuse_reply_ioctl(req, result, NULL, 0);
-
-			}
-
-			break;
-
-		case VHOST_SET_VRING_NUM:
-			LOG_DEBUG(VHOST_CONFIG, "(%"PRIu64") IOCTL: VHOST_SET_VRING_NUM\n", ctx.fh);
-			VHOST_IOCTL_R(struct vhost_vring_state, state, ops->set_vring_num);
-			break;
-
-		case VHOST_SET_VRING_BASE:
-			LOG_DEBUG(VHOST_CONFIG, "(%"PRIu64") IOCTL: VHOST_SET_VRING_BASE\n", ctx.fh);
-			VHOST_IOCTL_R(struct vhost_vring_state, state, ops->set_vring_base);
-			break;
-
-		case VHOST_GET_VRING_BASE:
-			LOG_DEBUG(VHOST_CONFIG, "(%"PRIu64") IOCTL: VHOST_GET_VRING_BASE\n", ctx.fh);
-			VHOST_IOCTL_RW(uint32_t, index, struct vhost_vring_state, state, ops->get_vring_base);
-			break;
-
-		case VHOST_SET_VRING_ADDR:
-			LOG_DEBUG(VHOST_CONFIG, "(%"PRIu64") IOCTL: VHOST_SET_VRING_ADDR\n", ctx.fh);
-			VHOST_IOCTL_R(struct vhost_vring_addr, addr, ops->set_vring_addr);
-			break;
-
-		case VHOST_SET_VRING_KICK:
-			LOG_DEBUG(VHOST_CONFIG, "(%"PRIu64") IOCTL: VHOST_SET_VRING_KICK\n", ctx.fh);
-			VHOST_IOCTL_R(struct vhost_vring_file, file, ops->set_vring_kick);
-			break;
-
-		case VHOST_SET_VRING_CALL:
-			LOG_DEBUG(VHOST_CONFIG, "(%"PRIu64") IOCTL: VHOST_SET_VRING_CALL\n", ctx.fh);
-			VHOST_IOCTL_R(struct vhost_vring_file, file, ops->set_vring_call);
-			break;
-
-		default:
-			RTE_LOG(ERR, VHOST_CONFIG, "(%"PRIu64") IOCTL: DOESN NOT EXIST\n", ctx.fh);
-			result = -1;
-			fuse_reply_ioctl(req, result, NULL, 0);
-	}
-
-	if (result < 0) {
-		LOG_DEBUG(VHOST_CONFIG, "(%"PRIu64") IOCTL: FAIL\n", ctx.fh);
-	} else {
-		LOG_DEBUG(VHOST_CONFIG, "(%"PRIu64") IOCTL: SUCCESS\n", ctx.fh);
-	}
-}
-
-/*
- * Structure handling open, release and ioctl function pointers is populated.
- */
-static const struct cuse_lowlevel_ops vhost_net_ops = {
-	.open		= vhost_net_open,
-	.release	= vhost_net_release,
-	.ioctl		= vhost_net_ioctl,
-};
-
-/*
- * cuse_info is populated and used to register the cuse device. vhost_net_device_ops are
- * also passed when the device is registered in main.c.
- */
-int
-register_cuse_device(const char *base_name, int index, struct vhost_net_device_ops const * const pops)
-{
-	struct cuse_info cuse_info;
-	char device_name[PATH_MAX] = "";
-	char char_device_name[PATH_MAX] = "";
-	const char *device_argv[] = { device_name };
-
-	char fuse_opt_dummy[] = FUSE_OPT_DUMMY;
-	char fuse_opt_fore[] = FUSE_OPT_FORE;
-	char fuse_opt_nomulti[] = FUSE_OPT_NOMULTI;
-	char *fuse_argv[] = {fuse_opt_dummy, fuse_opt_fore, fuse_opt_nomulti};
-
-	if (access(cuse_device_name, R_OK | W_OK) < 0) {
-		RTE_LOG(ERR, VHOST_CONFIG, "Character device %s can't be accessed, maybe not exist\n", cuse_device_name);
-		return -1;
-	}
-
-	/*
-	 * The device name is created. This is passed to QEMU so that it can register
-	 * the device with our application. The index allows us to have multiple instances
-	 * of userspace vhost which we can then add devices to separately.
-	 */
-	if (strncmp(base_name, default_cdev, PATH_MAX)!=0) {
-		snprintf(device_name, PATH_MAX, "DEVNAME=%s-%d", base_name, index);
-		snprintf(char_device_name, PATH_MAX, "/dev/%s-%d", base_name, index);
-	} else {
-		snprintf(device_name, PATH_MAX, "DEVNAME=%s", base_name);
-		snprintf(char_device_name, PATH_MAX, "/dev/%s", base_name);
-	}
-
-	/* Check if device already exists. */
-	if (access(char_device_name, F_OK) != -1) {
-		RTE_LOG(ERR, VHOST_CONFIG, "Character device %s already exists\n", char_device_name);
-		return -1;
-	}
-
-	memset(&cuse_info, 0, sizeof(cuse_info));
-	cuse_info.dev_major = default_major;
-	cuse_info.dev_minor = default_minor + index;
-	cuse_info.dev_info_argc = 1;
-	cuse_info.dev_info_argv = device_argv;
-	cuse_info.flags = CUSE_UNRESTRICTED_IOCTL;
-
-	ops = pops;
-
-	session = cuse_lowlevel_setup(3, fuse_argv,
-				&cuse_info, &vhost_net_ops, 0, NULL);
-	if (session == NULL)
-		return -1;
-
-	return 0;
-}
-
-/*
- * The CUSE session is launched allowing the application to receive open, release and ioctl calls.
- */
-int
-start_cuse_session_loop(void)
-{
-	fuse_session_loop(session);
-
-	return 0;
-}
diff --git a/examples/vhost/vhost-net-cdev.h b/examples/vhost/vhost-net-cdev.h
deleted file mode 100644
index 575daa9..0000000
--- a/examples/vhost/vhost-net-cdev.h
+++ /dev/null
@@ -1,83 +0,0 @@
-/*-
- *   BSD LICENSE
- *
- *   Copyright(c) 2010-2014 Intel Corporation. All rights reserved.
- *   All rights reserved.
- *
- *   Redistribution and use in source and binary forms, with or without
- *   modification, are permitted provided that the following conditions
- *   are met:
- *
- *     * Redistributions of source code must retain the above copyright
- *       notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above copyright
- *       notice, this list of conditions and the following disclaimer in
- *       the documentation and/or other materials provided with the
- *       distribution.
- *     * Neither the name of Intel Corporation nor the names of its
- *       contributors may be used to endorse or promote products derived
- *       from this software without specific prior written permission.
- *
- *   THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- *   "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- *   LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- *   A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- *   OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- *   SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- *   LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- *   DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- *   THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- *   (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- *   OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
- */
-
-#ifndef _VHOST_NET_CDEV_H_
-#define _VHOST_NET_CDEV_H_
-
-#include <linux/vhost.h>
-
-struct vhost_memory;
-struct vhost_vring_state;
-struct vhost_vring_addr;
-struct vhost_vring_file;
-
-/*
- * Structure used to identify device context.
- */
-struct vhost_device_ctx
-{
-	pid_t		pid;	/* PID of process calling the IOCTL. */
-	uint64_t 	fh;		/* Populated with fi->fh to track the device index. */
-};
-
-/*
- * Structure contains function pointers to be defined in virtio-net.c. These
- * functions are called in CUSE context and are used to configure devices.
- */
-struct vhost_net_device_ops {
-	int (* new_device) 		(struct vhost_device_ctx);
-	void (* destroy_device) (struct vhost_device_ctx);
-
-	int (* get_features) 	(struct vhost_device_ctx, uint64_t *);
-	int (* set_features) 	(struct vhost_device_ctx, uint64_t *);
-
-	int (* set_mem_table) 	(struct vhost_device_ctx, const void *, uint32_t);
-
-	int (* set_vring_num) 	(struct vhost_device_ctx, struct vhost_vring_state *);
-	int (* set_vring_addr) 	(struct vhost_device_ctx, struct vhost_vring_addr *);
-	int (* set_vring_base) 	(struct vhost_device_ctx, struct vhost_vring_state *);
-	int (* get_vring_base) 	(struct vhost_device_ctx, uint32_t, struct vhost_vring_state *);
-
-	int (* set_vring_kick) 	(struct vhost_device_ctx, struct vhost_vring_file *);
-	int (* set_vring_call) 	(struct vhost_device_ctx, struct vhost_vring_file *);
-
-	int (* set_backend) 	(struct vhost_device_ctx, struct vhost_vring_file *);
-
-	int (* set_owner) 		(struct vhost_device_ctx);
-	int (* reset_owner) 	(struct vhost_device_ctx);
-};
-
-int register_cuse_device(const char *base_name, int index, struct vhost_net_device_ops const * const);
-int start_cuse_session_loop(void);
-
-#endif /* _VHOST_NET_CDEV_H_ */
diff --git a/examples/vhost/virtio-net.c b/examples/vhost/virtio-net.c
deleted file mode 100644
index 5e659c7..0000000
--- a/examples/vhost/virtio-net.c
+++ /dev/null
@@ -1,1165 +0,0 @@
-/*-
- *   BSD LICENSE
- *
- *   Copyright(c) 2010-2014 Intel Corporation. All rights reserved.
- *   All rights reserved.
- *
- *   Redistribution and use in source and binary forms, with or without
- *   modification, are permitted provided that the following conditions
- *   are met:
- *
- *     * Redistributions of source code must retain the above copyright
- *       notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above copyright
- *       notice, this list of conditions and the following disclaimer in
- *       the documentation and/or other materials provided with the
- *       distribution.
- *     * Neither the name of Intel Corporation nor the names of its
- *       contributors may be used to endorse or promote products derived
- *       from this software without specific prior written permission.
- *
- *   THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- *   "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- *   LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- *   A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- *   OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- *   SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- *   LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- *   DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- *   THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- *   (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- *   OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
- */
-
-#include <dirent.h>
-#include <fuse/cuse_lowlevel.h>
-#include <linux/vhost.h>
-#include <linux/virtio_net.h>
-#include <stddef.h>
-#include <stdint.h>
-#include <stdlib.h>
-#include <sys/eventfd.h>
-#include <sys/ioctl.h>
-#include <sys/mman.h>
-#include <unistd.h>
-
-#include <rte_ethdev.h>
-#include <rte_log.h>
-#include <rte_string_fns.h>
-#include <rte_memory.h>
-
-#include "main.h"
-#include "virtio-net.h"
-#include "vhost-net-cdev.h"
-#include "eventfd_link/eventfd_link.h"
-
-const char eventfd_cdev[] = "/dev/eventfd-link";
-
-extern uint32_t num_devices;
-static uint32_t num_cur_devices = 0;
-
-/* device ops to add/remove device to data core. */
-static struct virtio_net_device_ops const * notify_ops;
-/* Root address of the linked list in the configuration core. */
-static struct virtio_net_config_ll			*ll_root = NULL;
-
-/* Features supported by this application. RX merge buffers are disabled by default. */
-uint64_t VHOST_FEATURES = (0ULL << VIRTIO_NET_F_MRG_RXBUF);
-
-/* Line size for reading maps file. */
-const uint32_t BUFSIZE = PATH_MAX;
-
-/* Size of prot char array in procmap. */
-#define PROT_SZ 5
-
-/* Number of elements in procmap struct. */
-#define PROCMAP_SZ 8
-
-/* Structure containing information gathered from maps file. */
-struct procmap
-{
-	uint64_t	va_start;			/* Start virtual address in file. */
-	uint64_t	len;				/* Size of file. */
-	uint64_t	pgoff;				/* Not used. */
-	uint32_t	maj;				/* Not used. */
-	uint32_t	min;				/* Not used. */
-	uint32_t	ino;				/* Not used. */
-	char		prot[PROT_SZ];		/* Not used. */
-	char		fname[PATH_MAX];	/* File name. */
-};
-
-/*
- * Converts QEMU virtual address to Vhost virtual address. This function is used
- * to convert the ring addresses to our address space.
- */
-static uint64_t
-qva_to_vva(struct virtio_net *dev, uint64_t qemu_va)
-{
-	struct virtio_memory_regions *region;
-	uint64_t vhost_va = 0;
-	uint32_t regionidx = 0;
-
-	/* Find the region where the address lives. */
-	for (regionidx = 0; regionidx < dev->mem->nregions; regionidx++) {
-		region = &dev->mem->regions[regionidx];
-		if ((qemu_va >= region->userspace_address) &&
-				(qemu_va <= region->userspace_address +
-			 	region->memory_size)) {
-			vhost_va = dev->mem->mapped_address + qemu_va - dev->mem->base_address;
-			break;
-		}
-	}
-	return vhost_va;
-}
-
-/*
- * Locate the file containing QEMU's memory space and map it to our address space.
- */
-static int
-host_memory_map (struct virtio_net *dev, struct virtio_memory *mem, pid_t pid, uint64_t addr)
-{
-	struct dirent *dptr = NULL;
-	struct procmap procmap;
-	DIR *dp = NULL;
-	int fd;
-	int i;
-	char memfile[PATH_MAX];
-	char mapfile[PATH_MAX];
-	char procdir[PATH_MAX];
-	char resolved_path[PATH_MAX];
-	FILE		*fmap;
-	void		*map;
-	uint8_t 	found = 0;
-	char 		line[BUFSIZE];
-	char dlm[] = "-   :   ";
-	char *str, *sp, *in[PROCMAP_SZ];
-	char *end = NULL;
-
-	/* Path where mem files are located. */
-	snprintf (procdir, PATH_MAX, "/proc/%u/fd/", pid);
-	/* Maps file used to locate mem file. */
-	snprintf (mapfile, PATH_MAX, "/proc/%u/maps", pid);
-
-	fmap = fopen(mapfile, "r");
-	if (fmap == NULL) {
-		RTE_LOG(ERR, VHOST_CONFIG, "(%"PRIu64") Failed to open maps file for pid %d\n", dev->device_fh, pid);
-		return -1;
-	}
-
-	/* Read through maps file until we find out base_address. */
-	while (fgets(line, BUFSIZE, fmap) != 0) {
-		str = line;
-		errno = 0;
-		/* Split line in to fields. */
-		for (i = 0; i < PROCMAP_SZ; i++) {
-			if (((in[i] = strtok_r(str, &dlm[i], &sp)) == NULL) || (errno != 0)) {
-				fclose(fmap);
-				return -1;
-			}
-			str = NULL;
-		}
-
-		/* Convert/Copy each field as needed. */
-		procmap.va_start = strtoull(in[0], &end, 16);
-		if ((in[0] == '\0') || (end == NULL) || (*end != '\0') || (errno != 0)) {
-			fclose(fmap);
-			return -1;
-		}
-
-		procmap.len = strtoull(in[1], &end, 16);
-		if ((in[1] == '\0') || (end == NULL) || (*end != '\0') || (errno != 0)) {
-			fclose(fmap);
-			return -1;
-		}
-
-		procmap.pgoff = strtoull(in[3], &end, 16);
-		if ((in[3] == '\0') || (end == NULL) || (*end != '\0') || (errno != 0)) {
-			fclose(fmap);
-			return -1;
-		}
-
-		procmap.maj = strtoul(in[4], &end, 16);
-		if ((in[4] == '\0') || (end == NULL) || (*end != '\0') || (errno != 0)) {
-			fclose(fmap);
-			return -1;
-		}
-
-		procmap.min = strtoul(in[5], &end, 16);
-		if ((in[5] == '\0') || (end == NULL) || (*end != '\0') || (errno != 0)) {
-			fclose(fmap);
-			return -1;
-		}
-
-		procmap.ino = strtoul(in[6], &end, 16);
-		if ((in[6] == '\0') || (end == NULL) || (*end != '\0') || (errno != 0)) {
-			fclose(fmap);
-			return -1;
-		}
-
-		memcpy(&procmap.prot, in[2], PROT_SZ);
-		memcpy(&procmap.fname, in[7], PATH_MAX);
-
-		if (procmap.va_start == addr) {
-			procmap.len = procmap.len - procmap.va_start;
-			found = 1;
-			break;
-		}
-	}
-	fclose(fmap);
-
-	if (!found) {
-		RTE_LOG(ERR, VHOST_CONFIG, "(%"PRIu64") Failed to find memory file in pid %d maps file\n", dev->device_fh, pid);
-		return -1;
-	}
-
-	/* Find the guest memory file among the process fds. */
-	dp = opendir(procdir);
-	if (dp == NULL) {
-		RTE_LOG(ERR, VHOST_CONFIG, "(%"PRIu64") Cannot open pid %d process directory \n", dev->device_fh, pid);
-		return -1;
-
-	}
-
-	found = 0;
-
-	/* Read the fd directory contents. */
-	while (NULL != (dptr = readdir(dp))) {
-		snprintf (memfile, PATH_MAX, "/proc/%u/fd/%s", pid, dptr->d_name);
-	    realpath(memfile, resolved_path);
-		if (resolved_path == NULL) {
-			RTE_LOG(ERR, VHOST_CONFIG, "(%"PRIu64") Failed to resolve fd directory\n", dev->device_fh);
-			closedir(dp);
-			return -1;
-		}
-		if (strncmp(resolved_path, procmap.fname,
-			strnlen(procmap.fname, PATH_MAX)) == 0) {
-			found = 1;
-			break;
-		}
-	}
-
-	closedir(dp);
-
-	if (found == 0) {
-		RTE_LOG(ERR, VHOST_CONFIG, "(%"PRIu64") Failed to find memory file for pid %d\n", dev->device_fh, pid);
-		return -1;
-	}
-	/* Open the shared memory file and map the memory into this process. */
-	fd = open(memfile, O_RDWR);
-
-	if (fd == -1) {
-		RTE_LOG(ERR, VHOST_CONFIG, "(%"PRIu64") Failed to open %s for pid %d\n", dev->device_fh, memfile, pid);
-		return -1;
-	}
-
-	map = mmap(0, (size_t)procmap.len, PROT_READ|PROT_WRITE , MAP_POPULATE|MAP_SHARED, fd, 0);
-	close (fd);
-
-	if (map == MAP_FAILED) {
-		RTE_LOG(ERR, VHOST_CONFIG, "(%"PRIu64") Error mapping the file %s for pid %d\n",  dev->device_fh, memfile, pid);
-		return -1;
-	}
-
-	/* Store the memory address and size in the device data structure */
-	mem->mapped_address = (uint64_t)(uintptr_t)map;
-	mem->mapped_size = procmap.len;
-
-	LOG_DEBUG(VHOST_CONFIG, "(%"PRIu64") Mem File: %s->%s - Size: %llu - VA: %p\n", dev->device_fh,
-		memfile, resolved_path, (long long unsigned)mem->mapped_size, map);
-
-	return 0;
-}
-
-/*
- * Retrieves an entry from the devices configuration linked list.
- */
-static struct virtio_net_config_ll *
-get_config_ll_entry(struct vhost_device_ctx ctx)
-{
-	struct virtio_net_config_ll *ll_dev = ll_root;
-
-	/* Loop through linked list until the device_fh is found. */
-	while (ll_dev != NULL) {
-		if (ll_dev->dev.device_fh == ctx.fh)
-			return ll_dev;
-		ll_dev = ll_dev->next;
-	}
-
-	return NULL;
-}
-
-/*
- * Searches the configuration core linked list and retrieves the device if it exists.
- */
-static struct virtio_net *
-get_device(struct vhost_device_ctx ctx)
-{
-	struct virtio_net_config_ll *ll_dev;
-
-	ll_dev = get_config_ll_entry(ctx);
-
-	/* If a matching entry is found in the linked list, return the device in that entry. */
-	if (ll_dev) {
-		return &ll_dev->dev;
-	}
-
-	RTE_LOG(ERR, VHOST_CONFIG, "(%"PRIu64") Device not found in linked list.\n", ctx.fh);
-	return NULL;
-}
-
-/*
- * Add entry containing a device to the device configuration linked list.
- */
-static void
-add_config_ll_entry(struct virtio_net_config_ll *new_ll_dev)
-{
-	struct virtio_net_config_ll *ll_dev = ll_root;
-
-	/* If ll_dev == NULL then this is the first device so go to else */
-	if (ll_dev) {
-		/* If the 1st device_fh != 0 then we insert our device here. */
-		if (ll_dev->dev.device_fh != 0)	{
-			new_ll_dev->dev.device_fh = 0;
-			new_ll_dev->next = ll_dev;
-			ll_root = new_ll_dev;
-		} else {
-			/* Increment through the ll until we find un unused device_fh. Insert the device at that entry*/
-			while ((ll_dev->next != NULL) && (ll_dev->dev.device_fh == (ll_dev->next->dev.device_fh - 1)))
-				ll_dev = ll_dev->next;
-
-			new_ll_dev->dev.device_fh = ll_dev->dev.device_fh + 1;
-			new_ll_dev->next = ll_dev->next;
-			ll_dev->next = new_ll_dev;
-		}
-	} else {
-		ll_root = new_ll_dev;
-		ll_root->dev.device_fh = 0;
-	}
-
-}
-
-/*
- * Unmap any memory, close any file descriptors and free any memory owned by a device.
- */
-static void
-cleanup_device(struct virtio_net *dev)
-{
-	/* Unmap QEMU memory file if mapped. */
-	if (dev->mem) {
-		munmap((void*)(uintptr_t)dev->mem->mapped_address, (size_t)dev->mem->mapped_size);
-		if (dev->mem->regions_hpa)
-			free(dev->mem->regions_hpa);
-		free(dev->mem);
-	}
-
-	/* Close any event notifiers opened by device. */
-	if (dev->virtqueue[VIRTIO_RXQ]->callfd)
-		close((int)dev->virtqueue[VIRTIO_RXQ]->callfd);
-	if (dev->virtqueue[VIRTIO_RXQ]->kickfd)
-		close((int)dev->virtqueue[VIRTIO_RXQ]->kickfd);
-	if (dev->virtqueue[VIRTIO_TXQ]->callfd)
-		close((int)dev->virtqueue[VIRTIO_TXQ]->callfd);
-	if (dev->virtqueue[VIRTIO_TXQ]->kickfd)
-		close((int)dev->virtqueue[VIRTIO_TXQ]->kickfd);
-}
-
-/*
- * Release virtqueues and device memory.
- */
-static void
-free_device(struct virtio_net_config_ll *ll_dev)
-{
-	/* Free any malloc'd memory */
-	free(ll_dev->dev.virtqueue[VIRTIO_RXQ]);
-	free(ll_dev->dev.virtqueue[VIRTIO_TXQ]);
-	free(ll_dev);
-}
-/*
- * Remove an entry from the device configuration linked list.
- */
-static struct virtio_net_config_ll *
-rm_config_ll_entry(struct virtio_net_config_ll *ll_dev, struct virtio_net_config_ll *ll_dev_last)
-{
-	/* First remove the device and then clean it up. */
-	if (ll_dev == ll_root) {
-		ll_root = ll_dev->next;
-		cleanup_device(&ll_dev->dev);
-		free_device(ll_dev);
-		return ll_root;
-	} else {
-		if (likely(ll_dev_last != NULL)) {
-			ll_dev_last->next = ll_dev->next;
-			cleanup_device(&ll_dev->dev);
-			free_device(ll_dev);
-			return ll_dev_last->next;
-		} else {
-			cleanup_device(&ll_dev->dev);
-			free_device(ll_dev);
-			RTE_LOG(ERR, VHOST_CONFIG, "Remove entry from config_ll failed\n");
-			return NULL;
-		}
-	}
-}
-
-/*
- *  Initialise all variables in device structure.
- */
-static void
-init_device(struct virtio_net *dev)
-{
-	uint64_t vq_offset;
-
-	/* Virtqueues have already been malloced so we don't want to set them to NULL. */
-	vq_offset = offsetof(struct virtio_net, mem);
-
-	/* Set everything to 0. */
-	memset((void*)(uintptr_t)((uint64_t)(uintptr_t)dev + vq_offset), 0,
-		(sizeof(struct virtio_net) - (size_t)vq_offset));
-	memset(dev->virtqueue[VIRTIO_RXQ], 0, sizeof(struct vhost_virtqueue));
-	memset(dev->virtqueue[VIRTIO_TXQ], 0, sizeof(struct vhost_virtqueue));
-
-	/* Backends are set to -1 indicating an inactive device. */
-	dev->virtqueue[VIRTIO_RXQ]->backend = VIRTIO_DEV_STOPPED;
-	dev->virtqueue[VIRTIO_TXQ]->backend = VIRTIO_DEV_STOPPED;
-}
-
-/*
- * Function is called from the CUSE open function. The device structure is
- * initialised and a new entry is added to the device configuration linked
- * list.
- */
-static int
-new_device(struct vhost_device_ctx ctx)
-{
-	struct virtio_net_config_ll *new_ll_dev;
-	struct vhost_virtqueue *virtqueue_rx, *virtqueue_tx;
-
-	/*check the number of devices in the system*/
-	if (num_cur_devices == num_devices) {
-		RTE_LOG(ERR, VHOST_CONFIG, "() Max num devices (%u) exceeded\n", num_devices);
-		return -1;
-	}
-
-	/* Setup device and virtqueues. */
-	new_ll_dev = malloc(sizeof(struct virtio_net_config_ll));
-	if (new_ll_dev == NULL) {
-		RTE_LOG(ERR, VHOST_CONFIG, "(%"PRIu64") Failed to allocate memory for dev.\n", ctx.fh);
-		return -1;
-	}
-
-	virtqueue_rx = malloc(sizeof(struct vhost_virtqueue));
-	if (virtqueue_rx == NULL) {
-		free(new_ll_dev);
-		RTE_LOG(ERR, VHOST_CONFIG, "(%"PRIu64") Failed to allocate memory for virtqueue_rx.\n", ctx.fh);
-		return -1;
-	}
-
-	virtqueue_tx = malloc(sizeof(struct vhost_virtqueue));
-	if (virtqueue_tx == NULL) {
-		free(virtqueue_rx);
-		free(new_ll_dev);
-		RTE_LOG(ERR, VHOST_CONFIG, "(%"PRIu64") Failed to allocate memory for virtqueue_tx.\n", ctx.fh);
-		return -1;
-	}
-
-	new_ll_dev->dev.virtqueue[VIRTIO_RXQ] = virtqueue_rx;
-	new_ll_dev->dev.virtqueue[VIRTIO_TXQ] = virtqueue_tx;
-
-	/* Initialise device and virtqueues. */
-	init_device(&new_ll_dev->dev);
-
-	new_ll_dev->next = NULL;
-
-	/* Add entry to device configuration linked list. */
-	add_config_ll_entry(new_ll_dev);
-
-	/*increment the number of devices in the system*/
-	num_cur_devices++;
-
-	return new_ll_dev->dev.device_fh;
-}
-
-/*
- * Function is called from the CUSE release function. This function will cleanup
- * the device and remove it from device configuration linked list.
- */
-static void
-destroy_device(struct vhost_device_ctx ctx)
-{
-	struct virtio_net_config_ll *ll_dev_cur_ctx, *ll_dev_last = NULL;
-	struct virtio_net_config_ll *ll_dev_cur = ll_root;
-
-	/* Find the linked list entry for the device to be removed. */
-	ll_dev_cur_ctx = get_config_ll_entry(ctx);
-	while (ll_dev_cur != NULL) {
-		/* If the device is found or a device that doesn't exist is found then it is removed. */
-		if (ll_dev_cur == ll_dev_cur_ctx) {
-			/*
-			 * If the device is running on a data core then call the function to remove it from
-			 * the data core.
-			 */
-			if ((ll_dev_cur->dev.flags & VIRTIO_DEV_RUNNING))
-				notify_ops->destroy_device(&(ll_dev_cur->dev));
-			ll_dev_cur = rm_config_ll_entry(ll_dev_cur, ll_dev_last);
-		} else {
-			ll_dev_last = ll_dev_cur;
-			ll_dev_cur = ll_dev_cur->next;
-		}
-	}
-
-	/*decrement the number of devices in the system*/
-	num_cur_devices--;
-}
-
-/*
- * Called from CUSE IOCTL: VHOST_SET_OWNER
- * This function just returns success at the moment unless the device hasn't been initialised.
- */
-static int
-set_owner(struct vhost_device_ctx ctx)
-{
-	struct virtio_net *dev;
-
-	dev = get_device(ctx);
-	if (dev == NULL)
-		return -1;
-
-	return 0;
-}
-
-/*
- * Called from CUSE IOCTL: VHOST_RESET_OWNER
- */
-static int
-reset_owner(struct vhost_device_ctx ctx)
-{
-	struct virtio_net_config_ll *ll_dev;
-
-	ll_dev = get_config_ll_entry(ctx);
-
-	cleanup_device(&ll_dev->dev);
-	init_device(&ll_dev->dev);
-
-	return 0;
-}
-
-/*
- * Called from CUSE IOCTL: VHOST_GET_FEATURES
- * The features that we support are requested.
- */
-static int
-get_features(struct vhost_device_ctx ctx, uint64_t *pu)
-{
-	struct virtio_net *dev;
-
-	dev = get_device(ctx);
-	if (dev == NULL)
-		return -1;
-
-	/* Send our supported features. */
-	*pu = VHOST_FEATURES;
-	return 0;
-}
-
-/*
- * Called from CUSE IOCTL: VHOST_SET_FEATURES
- * We receive the negotiated set of features supported by us and the virtio device.
- */
-static int
-set_features(struct vhost_device_ctx ctx, uint64_t *pu)
-{
-	struct virtio_net *dev;
-
-	dev = get_device(ctx);
-	if (dev == NULL)
-		return -1;
-	if (*pu & ~VHOST_FEATURES)
-		return -1;
-
-	/* Store the negotiated feature list for the device. */
-	dev->features = *pu;
-
-	/* Set the vhost_hlen depending on if VIRTIO_NET_F_MRG_RXBUF is set. */
-	if (dev->features & (1 << VIRTIO_NET_F_MRG_RXBUF)) {
-		LOG_DEBUG(VHOST_CONFIG, "(%"PRIu64") Mergeable RX buffers enabled\n", dev->device_fh);
-		dev->virtqueue[VIRTIO_RXQ]->vhost_hlen = sizeof(struct virtio_net_hdr_mrg_rxbuf);
-		dev->virtqueue[VIRTIO_TXQ]->vhost_hlen = sizeof(struct virtio_net_hdr_mrg_rxbuf);
-	} else {
-		LOG_DEBUG(VHOST_CONFIG, "(%"PRIu64") Mergeable RX buffers disabled\n", dev->device_fh);
-		dev->virtqueue[VIRTIO_RXQ]->vhost_hlen = sizeof(struct virtio_net_hdr);
-		dev->virtqueue[VIRTIO_TXQ]->vhost_hlen = sizeof(struct virtio_net_hdr);
-	}
-	return 0;
-}
-
-/*
- * Calculate the region count of physical continous regions for one particular
- * region of whose vhost virtual address is continous. The particular region
- * start from vva_start, with size of 'size' in argument.
- */
-static uint32_t check_hpa_regions(uint64_t vva_start, uint64_t size)
-{
-	uint32_t i, nregions = 0, page_size = PAGE_SIZE;
-	uint64_t cur_phys_addr = 0, next_phys_addr = 0;
-	if (vva_start % page_size) {
-		LOG_DEBUG(VHOST_CONFIG,
-			"in check_countinous: vva start(%p) mod page_size(%d) "
-			"has remainder\n",
-			(void *)(uintptr_t)vva_start, page_size);
-		return 0;
-	}
-	if (size % page_size) {
-		LOG_DEBUG(VHOST_CONFIG,
-			"in check_countinous: "
-			"size((%"PRIu64")) mod page_size(%d) has remainder\n",
-			size, page_size);
-		return 0;
-	}
-	for (i = 0; i < size - page_size; i = i + page_size) {
-		cur_phys_addr
-			= rte_mem_virt2phy((void *)(uintptr_t)(vva_start + i));
-		next_phys_addr = rte_mem_virt2phy(
-			(void *)(uintptr_t)(vva_start + i + page_size));
-		if ((cur_phys_addr + page_size) != next_phys_addr) {
-			++nregions;
-			LOG_DEBUG(VHOST_CONFIG,
-				"in check_continuous: hva addr:(%p) is not "
-				"continuous with hva addr:(%p), diff:%d\n",
-				(void *)(uintptr_t)(vva_start + (uint64_t)i),
-				(void *)(uintptr_t)(vva_start + (uint64_t)i
-				+ page_size), page_size);
-			LOG_DEBUG(VHOST_CONFIG,
-				"in check_continuous: hpa addr:(%p) is not "
-				"continuous with hpa addr:(%p), "
-				"diff:(%"PRIu64")\n",
-				(void *)(uintptr_t)cur_phys_addr,
-				(void *)(uintptr_t)next_phys_addr,
-				(next_phys_addr-cur_phys_addr));
-		}
-	}
-	return nregions;
-}
-
-/*
- * Divide each region whose vhost virtual address is continous into a few
- * sub-regions, make sure the physical address within each sub-region are
- * continous. And fill offset(to GPA) and size etc. information of each
- * sub-region into regions_hpa.
- */
-static uint32_t fill_hpa_memory_regions(void *memory)
-{
-	uint32_t regionidx, regionidx_hpa = 0, i, k, page_size = PAGE_SIZE;
-	uint64_t cur_phys_addr = 0, next_phys_addr = 0, vva_start;
-	struct virtio_memory *virtio_memory = (struct virtio_memory *)memory;
-	struct virtio_memory_regions_hpa *mem_region_hpa
-		= virtio_memory->regions_hpa;
-
-	if (mem_region_hpa == NULL)
-		return 0;
-
-	for (regionidx = 0; regionidx < virtio_memory->nregions; regionidx++) {
-		vva_start = virtio_memory->regions[regionidx].guest_phys_address
-			+ virtio_memory->regions[regionidx].address_offset;
-		mem_region_hpa[regionidx_hpa].guest_phys_address
-			= virtio_memory->regions[regionidx].guest_phys_address;
-		mem_region_hpa[regionidx_hpa].host_phys_addr_offset =
-			rte_mem_virt2phy((void *)(uintptr_t)(vva_start))
-			- mem_region_hpa[regionidx_hpa].guest_phys_address;
-		LOG_DEBUG(VHOST_CONFIG,
-			"in fill_hpa_regions: guest phys addr start[%d]:(%p)\n",
-			regionidx_hpa,
-			(void *)(uintptr_t)
-			(mem_region_hpa[regionidx_hpa].guest_phys_address));
-		LOG_DEBUG(VHOST_CONFIG,
-			"in fill_hpa_regions: host  phys addr start[%d]:(%p)\n",
-			regionidx_hpa,
-			(void *)(uintptr_t)
-			(mem_region_hpa[regionidx_hpa].host_phys_addr_offset));
-		for (i = 0, k = 0;
-			i < virtio_memory->regions[regionidx].memory_size
-				- page_size;
-			i += page_size) {
-			cur_phys_addr = rte_mem_virt2phy(
-					(void *)(uintptr_t)(vva_start + i));
-			next_phys_addr = rte_mem_virt2phy(
-					(void *)(uintptr_t)(vva_start
-					+ i + page_size));
-			if ((cur_phys_addr + page_size) != next_phys_addr) {
-				mem_region_hpa[regionidx_hpa].guest_phys_address_end =
-					mem_region_hpa[regionidx_hpa].guest_phys_address
-					+ k + page_size;
-				mem_region_hpa[regionidx_hpa].memory_size
-					= k + page_size;
-				LOG_DEBUG(VHOST_CONFIG, "in fill_hpa_regions: guest "
-					"phys addr end  [%d]:(%p)\n",
-					regionidx_hpa,
-					(void *)(uintptr_t)
-					(mem_region_hpa[regionidx_hpa].guest_phys_address_end));
-				LOG_DEBUG(VHOST_CONFIG,
-					"in fill_hpa_regions: guest phys addr "
-					"size [%d]:(%p)\n",
-					regionidx_hpa,
-					(void *)(uintptr_t)
-					(mem_region_hpa[regionidx_hpa].memory_size));
-				mem_region_hpa[regionidx_hpa + 1].guest_phys_address
-					= mem_region_hpa[regionidx_hpa].guest_phys_address_end;
-				++regionidx_hpa;
-				mem_region_hpa[regionidx_hpa].host_phys_addr_offset =
-					next_phys_addr
-					- mem_region_hpa[regionidx_hpa].guest_phys_address;
-				LOG_DEBUG(VHOST_CONFIG, "in fill_hpa_regions: guest"
-					" phys addr start[%d]:(%p)\n",
-					regionidx_hpa,
-					(void *)(uintptr_t)
-					(mem_region_hpa[regionidx_hpa].guest_phys_address));
-				LOG_DEBUG(VHOST_CONFIG,
-					"in fill_hpa_regions: host  phys addr "
-					"start[%d]:(%p)\n",
-					regionidx_hpa,
-					(void *)(uintptr_t)
-					(mem_region_hpa[regionidx_hpa].host_phys_addr_offset));
-				k = 0;
-			} else {
-				k += page_size;
-			}
-		}
-		mem_region_hpa[regionidx_hpa].guest_phys_address_end
-			= mem_region_hpa[regionidx_hpa].guest_phys_address
-			+ k + page_size;
-		mem_region_hpa[regionidx_hpa].memory_size = k + page_size;
-		LOG_DEBUG(VHOST_CONFIG, "in fill_hpa_regions: guest phys addr end  "
-			"[%d]:(%p)\n", regionidx_hpa,
-			(void *)(uintptr_t)
-			(mem_region_hpa[regionidx_hpa].guest_phys_address_end));
-		LOG_DEBUG(VHOST_CONFIG, "in fill_hpa_regions: guest phys addr size "
-			"[%d]:(%p)\n", regionidx_hpa,
-			(void *)(uintptr_t)
-			(mem_region_hpa[regionidx_hpa].memory_size));
-		++regionidx_hpa;
-	}
-	return regionidx_hpa;
-}
-
-/*
- * Called from CUSE IOCTL: VHOST_SET_MEM_TABLE
- * This function creates and populates the memory structure for the device. This includes
- * storing offsets used to translate buffer addresses.
- */
-static int
-set_mem_table(struct vhost_device_ctx ctx, const void *mem_regions_addr, uint32_t nregions)
-{
-	struct virtio_net *dev;
-	struct vhost_memory_region *mem_regions;
-	struct virtio_memory *mem;
-	uint64_t size = offsetof(struct vhost_memory, regions);
-	uint32_t regionidx, valid_regions;
-
-	dev = get_device(ctx);
-	if (dev == NULL)
-		return -1;
-
-	if (dev->mem) {
-		munmap((void*)(uintptr_t)dev->mem->mapped_address, (size_t)dev->mem->mapped_size);
-		free(dev->mem);
-	}
-
-	/* Malloc the memory structure depending on the number of regions. */
-	mem = calloc(1, sizeof(struct virtio_memory) + (sizeof(struct virtio_memory_regions) * nregions));
-	if (mem == NULL) {
-		RTE_LOG(ERR, VHOST_CONFIG, "(%"PRIu64") Failed to allocate memory for dev->mem.\n", dev->device_fh);
-		return -1;
-	}
-
-	mem->nregions = nregions;
-
-	mem_regions = (void*)(uintptr_t)((uint64_t)(uintptr_t)mem_regions_addr + size);
-
-	for (regionidx = 0; regionidx < mem->nregions; regionidx++) {
-		/* Populate the region structure for each region. */
-		mem->regions[regionidx].guest_phys_address = mem_regions[regionidx].guest_phys_addr;
-		mem->regions[regionidx].guest_phys_address_end = mem->regions[regionidx].guest_phys_address +
-			mem_regions[regionidx].memory_size;
-		mem->regions[regionidx].memory_size = mem_regions[regionidx].memory_size;
-		mem->regions[regionidx].userspace_address = mem_regions[regionidx].userspace_addr;
-
-		LOG_DEBUG(VHOST_CONFIG, "(%"PRIu64") REGION: %u - GPA: %p - QEMU VA: %p - SIZE (%"PRIu64")\n", dev->device_fh,
-				regionidx, (void*)(uintptr_t)mem->regions[regionidx].guest_phys_address,
-				(void*)(uintptr_t)mem->regions[regionidx].userspace_address,
-				mem->regions[regionidx].memory_size);
-
-		/*set the base address mapping*/
-		if (mem->regions[regionidx].guest_phys_address == 0x0) {
-			mem->base_address = mem->regions[regionidx].userspace_address;
-			/* Map VM memory file */
-			if (host_memory_map(dev, mem, ctx.pid, mem->base_address) != 0) {
-				free(mem);
-				return -1;
-			}
-		}
-	}
-
-	/* Check that we have a valid base address. */
-	if (mem->base_address == 0) {
-		RTE_LOG(ERR, VHOST_CONFIG, "(%"PRIu64") Failed to find base address of qemu memory file.\n", dev->device_fh);
-		free(mem);
-		return -1;
-	}
-
-	/* Check if all of our regions have valid mappings. Usually one does not exist in the QEMU memory file. */
-	valid_regions = mem->nregions;
-	for (regionidx = 0; regionidx < mem->nregions; regionidx++) {
-		if ((mem->regions[regionidx].userspace_address < mem->base_address) ||
-			(mem->regions[regionidx].userspace_address > (mem->base_address + mem->mapped_size)))
-				valid_regions--;
-	}
-
-	/* If a region does not have a valid mapping we rebuild our memory struct to contain only valid entries. */
-	if (valid_regions != mem->nregions) {
-		LOG_DEBUG(VHOST_CONFIG, "(%"PRIu64") Not all memory regions exist in the QEMU mem file. Re-populating mem structure\n",
-			dev->device_fh);
-
-		/* Re-populate the memory structure with only valid regions. Invalid regions are over-written with memmove. */
-		valid_regions = 0;
-
-		for (regionidx = mem->nregions; 0 != regionidx--;) {
-			if ((mem->regions[regionidx].userspace_address < mem->base_address) ||
-					(mem->regions[regionidx].userspace_address > (mem->base_address + mem->mapped_size))) {
-				memmove(&mem->regions[regionidx], &mem->regions[regionidx + 1],
-					sizeof(struct virtio_memory_regions) * valid_regions);
-			} else {
-				valid_regions++;
-			}
-		}
-	}
-	mem->nregions = valid_regions;
-	mem->nregions_hpa = mem->nregions;
-	dev->mem = mem;
-
-	/*
-	 * Calculate the address offset for each region. This offset is used to identify the vhost virtual address
-	 * corresponding to a QEMU guest physical address.
-	 */
-	for (regionidx = 0; regionidx < dev->mem->nregions; regionidx++) {
-		dev->mem->regions[regionidx].address_offset = dev->mem->regions[regionidx].userspace_address - dev->mem->base_address
-			+ dev->mem->mapped_address - dev->mem->regions[regionidx].guest_phys_address;
-
-		dev->mem->nregions_hpa
-			+= check_hpa_regions(
-				dev->mem->regions[regionidx].guest_phys_address
-				+ dev->mem->regions[regionidx].address_offset,
-				dev->mem->regions[regionidx].memory_size);
-	}
-	if (dev->mem->regions_hpa != NULL) {
-		free(dev->mem->regions_hpa);
-		dev->mem->regions_hpa = NULL;
-	}
-
-	dev->mem->regions_hpa = (struct virtio_memory_regions_hpa *) calloc(1,
-		(sizeof(struct virtio_memory_regions_hpa)
-		* dev->mem->nregions_hpa));
-	if (dev->mem->regions_hpa == NULL) {
-		RTE_LOG(ERR, VHOST_CONFIG,
-			"(%"PRIu64") Failed to allocate memory for "
-			"dev->mem->regions_hpa.\n", dev->device_fh);
-		return -1;
-	}
-	if (fill_hpa_memory_regions(
-		(void *)dev->mem) != dev->mem->nregions_hpa) {
-		RTE_LOG(ERR, VHOST_CONFIG,
-			"in set_mem_table: hpa memory regions number mismatch: "
-			"[%d]\n", dev->mem->nregions_hpa);
-		return -1;
-	}
-
-	return 0;
-}
-
-/*
- * Called from CUSE IOCTL: VHOST_SET_VRING_NUM
- * The virtio device sends us the size of the descriptor ring.
- */
-static int
-set_vring_num(struct vhost_device_ctx ctx, struct vhost_vring_state *state)
-{
-	struct virtio_net *dev;
-
-	dev = get_device(ctx);
-	if (dev == NULL)
-		return -1;
-
-	/* State->index refers to the queue index. The TX queue is 1, RX queue is 0. */
-	dev->virtqueue[state->index]->size = state->num;
-
-	return 0;
-}
-
-/*
- * Called from CUSE IOCTL: VHOST_SET_VRING_ADDR
- * The virtio device sends us the desc, used and avail ring addresses. This function
- * then converts these to our address space.
- */
-static int
-set_vring_addr(struct vhost_device_ctx ctx, struct vhost_vring_addr *addr)
-{
-	struct virtio_net *dev;
-	struct vhost_virtqueue *vq;
-
-	dev = get_device(ctx);
-	if (dev == NULL)
-		return -1;
-
-	/* addr->index refers to the queue index. The TX queue is 1, RX queue is 0. */
-	vq = dev->virtqueue[addr->index];
-
-	/* The addresses are converted from QEMU virtual to Vhost virtual. */
-	vq->desc = (struct vring_desc*)(uintptr_t)qva_to_vva(dev, addr->desc_user_addr);
-	if (vq->desc == 0) {
-		RTE_LOG(ERR, VHOST_CONFIG, "(%"PRIu64") Failed to find descriptor ring address.\n", dev->device_fh);
-		return -1;
-	}
-
-	vq->avail = (struct vring_avail*)(uintptr_t)qva_to_vva(dev, addr->avail_user_addr);
-	if (vq->avail == 0) {
-		RTE_LOG(ERR, VHOST_CONFIG, "(%"PRIu64") Failed to find available ring address.\n", dev->device_fh);
-		return -1;
-	}
-
-	vq->used = (struct vring_used*)(uintptr_t)qva_to_vva(dev, addr->used_user_addr);
-	if (vq->used == 0) {
-		RTE_LOG(ERR, VHOST_CONFIG, "(%"PRIu64") Failed to find used ring address.\n", dev->device_fh);
-		return -1;
-	}
-
-	LOG_DEBUG(VHOST_CONFIG, "(%"PRIu64") mapped address desc: %p\n", dev->device_fh, vq->desc);
-	LOG_DEBUG(VHOST_CONFIG, "(%"PRIu64") mapped address avail: %p\n", dev->device_fh, vq->avail);
-	LOG_DEBUG(VHOST_CONFIG, "(%"PRIu64") mapped address used: %p\n", dev->device_fh, vq->used);
-
-	return 0;
-}
-
-/*
- * Called from CUSE IOCTL: VHOST_SET_VRING_BASE
- * The virtio device sends us the available ring last used index.
- */
-static int
-set_vring_base(struct vhost_device_ctx ctx, struct vhost_vring_state *state)
-{
-	struct virtio_net *dev;
-
-	dev = get_device(ctx);
-	if (dev == NULL)
-		return -1;
-
-	/* State->index refers to the queue index. The TX queue is 1, RX queue is 0. */
-	dev->virtqueue[state->index]->last_used_idx = state->num;
-	dev->virtqueue[state->index]->last_used_idx_res = state->num;
-
-	return 0;
-}
-
-/*
- * Called from CUSE IOCTL: VHOST_GET_VRING_BASE
- * We send the virtio device our available ring last used index.
- */
-static int
-get_vring_base(struct vhost_device_ctx ctx, uint32_t index, struct vhost_vring_state *state)
-{
-	struct virtio_net *dev;
-
-	dev = get_device(ctx);
-	if (dev == NULL)
-		return -1;
-
-	state->index = index;
-	/* State->index refers to the queue index. The TX queue is 1, RX queue is 0. */
-	state->num = dev->virtqueue[state->index]->last_used_idx;
-
-	return 0;
-}
-
-/*
- * This function uses the eventfd_link kernel module to copy an eventfd file descriptor
- * provided by QEMU in to our process space.
- */
-static int
-eventfd_copy(struct virtio_net *dev, struct eventfd_copy *eventfd_copy)
-{
-	int eventfd_link, ret;
-
-	/* Open the character device to the kernel module. */
-	eventfd_link = open(eventfd_cdev, O_RDWR);
-	if (eventfd_link < 0) {
-		RTE_LOG(ERR, VHOST_CONFIG, "(%"PRIu64") eventfd_link module is not loaded\n",  dev->device_fh);
-		return -1;
-	}
-
-	/* Call the IOCTL to copy the eventfd. */
-	ret = ioctl(eventfd_link, EVENTFD_COPY, eventfd_copy);
-	close(eventfd_link);
-
-	if (ret < 0) {
-		RTE_LOG(ERR, VHOST_CONFIG, "(%"PRIu64") EVENTFD_COPY ioctl failed\n",  dev->device_fh);
-		return -1;
-	}
-
-
-	return 0;
-}
-
-/*
- * Called from CUSE IOCTL: VHOST_SET_VRING_CALL
- * The virtio device sends an eventfd to interrupt the guest. This fd gets copied in
- * to our process space.
- */
-static int
-set_vring_call(struct vhost_device_ctx ctx, struct vhost_vring_file *file)
-{
-	struct virtio_net *dev;
-	struct eventfd_copy	eventfd_kick;
-	struct vhost_virtqueue *vq;
-
-	dev = get_device(ctx);
-	if (dev == NULL)
-		return -1;
-
-	/* file->index refers to the queue index. The TX queue is 1, RX queue is 0. */
-	vq = dev->virtqueue[file->index];
-
-	if (vq->kickfd)
-		close((int)vq->kickfd);
-
-	/* Populate the eventfd_copy structure and call eventfd_copy. */
-	vq->kickfd = eventfd(0, EFD_NONBLOCK | EFD_CLOEXEC);
-	eventfd_kick.source_fd = vq->kickfd;
-	eventfd_kick.target_fd = file->fd;
-	eventfd_kick.target_pid = ctx.pid;
-
-	if (eventfd_copy(dev, &eventfd_kick))
-		return -1;
-
-	return 0;
-}
-
-/*
- * Called from CUSE IOCTL: VHOST_SET_VRING_KICK
- * The virtio device sends an eventfd that it can use to notify us. This fd gets copied in
- * to our process space.
- */
-static int
-set_vring_kick(struct vhost_device_ctx ctx, struct vhost_vring_file *file)
-{
-	struct virtio_net *dev;
-	struct eventfd_copy eventfd_call;
-	struct vhost_virtqueue *vq;
-
-	dev = get_device(ctx);
-	if (dev == NULL)
-		return -1;
-
-	/* file->index refers to the queue index. The TX queue is 1, RX queue is 0. */
-	vq = dev->virtqueue[file->index];
-
-	if (vq->callfd)
-		close((int)vq->callfd);
-
-	/* Populate the eventfd_copy structure and call eventfd_copy. */
-	vq->callfd = eventfd(0, EFD_NONBLOCK | EFD_CLOEXEC);
-	eventfd_call.source_fd = vq->callfd;
-	eventfd_call.target_fd = file->fd;
-	eventfd_call.target_pid = ctx.pid;
-
-	if (eventfd_copy(dev, &eventfd_call))
-        return -1;
-
-	return 0;
-}
-
-/*
- * Called from CUSE IOCTL: VHOST_NET_SET_BACKEND
- * To complete device initialisation when the virtio driver is loaded we are provided with a
- * valid fd for a tap device (not used by us). If this happens then we can add the device to a
- * data core. When the virtio driver is removed we get fd=-1. At that point we remove the device
- * from the data core. The device will still exist in the device configuration linked list.
- */
-static int
-set_backend(struct vhost_device_ctx ctx, struct vhost_vring_file *file)
-{
-	struct virtio_net *dev;
-
-	dev = get_device(ctx);
-	if (dev == NULL) {
-		return -1;
-	}
-
-	/* file->index refers to the queue index. The TX queue is 1, RX queue is 0. */
-	dev->virtqueue[file->index]->backend = file->fd;
-
-	/* If the device isn't already running and both backend fds are set we add the device. */
-	if (!(dev->flags & VIRTIO_DEV_RUNNING)) {
-		if (((int)dev->virtqueue[VIRTIO_TXQ]->backend != VIRTIO_DEV_STOPPED) &&
-			((int)dev->virtqueue[VIRTIO_RXQ]->backend != VIRTIO_DEV_STOPPED))
-			return notify_ops->new_device(dev);
-	/* Otherwise we remove it. */
-	} else
-		if (file->fd == VIRTIO_DEV_STOPPED) {
-			notify_ops->destroy_device(dev);
-		}
-	return 0;
-}
-
-/*
- * Function pointers are set for the device operations to allow CUSE to call functions
- * when an IOCTL, device_add or device_release is received.
- */
-static const struct vhost_net_device_ops vhost_device_ops =
-{
-	.new_device = new_device,
-	.destroy_device = destroy_device,
-
-	.get_features = get_features,
-	.set_features = set_features,
-
-	.set_mem_table = set_mem_table,
-
-	.set_vring_num = set_vring_num,
-	.set_vring_addr = set_vring_addr,
-	.set_vring_base = set_vring_base,
-	.get_vring_base = get_vring_base,
-
-	.set_vring_kick = set_vring_kick,
-	.set_vring_call = set_vring_call,
-
-	.set_backend = set_backend,
-
-	.set_owner = set_owner,
-	.reset_owner = reset_owner,
-};
-
-/*
- * Called by main to setup callbacks when registering CUSE device.
- */
-struct vhost_net_device_ops const *
-get_virtio_net_callbacks(void)
-{
-	return &vhost_device_ops;
-}
-
-/*
- * Register ops so that we can add/remove device to data core.
- */
-int
-init_virtio_net(struct virtio_net_device_ops const * const ops)
-{
-	notify_ops = ops;
-
-	return 0;
-}
-
-/*
- * Currently not used as we Ctrl+c to exit application.
- */
-int
-deinit_virtio_net(void)
-{
-	return 0;
-}
diff --git a/examples/vhost/virtio-net.h b/examples/vhost/virtio-net.h
deleted file mode 100644
index 1a2f0dc..0000000
--- a/examples/vhost/virtio-net.h
+++ /dev/null
@@ -1,161 +0,0 @@
-/*-
- *   BSD LICENSE
- *
- *   Copyright(c) 2010-2014 Intel Corporation. All rights reserved.
- *   All rights reserved.
- *
- *   Redistribution and use in source and binary forms, with or without
- *   modification, are permitted provided that the following conditions
- *   are met:
- *
- *     * Redistributions of source code must retain the above copyright
- *       notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above copyright
- *       notice, this list of conditions and the following disclaimer in
- *       the documentation and/or other materials provided with the
- *       distribution.
- *     * Neither the name of Intel Corporation nor the names of its
- *       contributors may be used to endorse or promote products derived
- *       from this software without specific prior written permission.
- *
- *   THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- *   "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- *   LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- *   A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- *   OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- *   SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- *   LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- *   DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- *   THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- *   (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- *   OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
- */
-
-#ifndef _VIRTIO_NET_H_
-#define _VIRTIO_NET_H_
-
-/* Used to indicate that the device is running on a data core */
-#define VIRTIO_DEV_RUNNING 1
-
-/* Backend value set by guest. */
-#define VIRTIO_DEV_STOPPED -1
-
-#define PAGE_SIZE   4096
-
-/* Enum for virtqueue management. */
-enum {VIRTIO_RXQ, VIRTIO_TXQ, VIRTIO_QNUM};
-
-#define BUF_VECTOR_MAX 256
-
-/*
- * Structure contains buffer address, length and descriptor index
- * from vring to do scatter RX.
-*/
-struct buf_vector {
-uint64_t buf_addr;
-uint32_t buf_len;
-uint32_t desc_idx;
-};
-
-/*
- * Structure contains variables relevant to TX/RX virtqueues.
- */
-struct vhost_virtqueue
-{
-	struct vring_desc	*desc;				/* Virtqueue descriptor ring. */
-	struct vring_avail	*avail;				/* Virtqueue available ring. */
-	struct vring_used	*used;				/* Virtqueue used ring. */
-	uint32_t			size;				/* Size of descriptor ring. */
-	uint32_t			backend;			/* Backend value to determine if device should started/stopped. */
-	uint16_t			vhost_hlen;			/* Vhost header length (varies depending on RX merge buffers. */
-	volatile uint16_t	last_used_idx;		/* Last index used on the available ring */
-	volatile uint16_t	last_used_idx_res;	/* Used for multiple devices reserving buffers. */
-	eventfd_t			callfd;				/* Currently unused as polling mode is enabled. */
-	eventfd_t			kickfd;				/* Used to notify the guest (trigger interrupt). */
-	/* Used for scatter RX. */
-	struct buf_vector	buf_vec[BUF_VECTOR_MAX];
-} __rte_cache_aligned;
-
-/*
- * Device structure contains all configuration information relating to the device.
- */
-struct virtio_net
-{
-	struct vhost_virtqueue	*virtqueue[VIRTIO_QNUM];	/* Contains all virtqueue information. */
-	struct virtio_memory 	*mem;						/* QEMU memory and memory region information. */
-	struct ether_addr 		mac_address;				/* Device MAC address (Obtained on first TX packet). */
-	uint64_t 				features;					/* Negotiated feature set. */
-	uint64_t 				device_fh;					/* device identifier. */
-	uint32_t 				vmdq_rx_q;					/* RX VMDQ queue number. */
-	uint32_t 				flags;						/* Device flags. Only used to check if device is running on data core. */
-	uint32_t 				vlan_tag;					/* Vlan tag for device. Currently set to device_id (0-63). */
-	uint16_t 				coreid;						/* Data core that the device is added to. */
-	volatile uint8_t 		ready;						/* A device is set as ready if the MAC address has been set. */
-	volatile uint8_t		remove;						/* Device is marked for removal from the data core. */
-} __rte_cache_aligned;
-
-/*
- * Device linked list structure for configuration.
- */
-struct virtio_net_config_ll
-{
-	struct virtio_net		dev;	/* Virtio device. */
-	struct virtio_net_config_ll	*next; /* Next entry on linked list. */
-};
-
-/*
- * Information relating to memory regions including offsets to addresses in QEMUs memory file.
- */
-struct virtio_memory_regions {
-	uint64_t	guest_phys_address;		/* Base guest physical address of region. */
-	uint64_t	guest_phys_address_end;	/* End guest physical address of region. */
-	uint64_t	memory_size;			/* Size of region. */
-	uint64_t	userspace_address;		/* Base userspace address of region. */
-	uint64_t	address_offset;			/* Offset of region for address translation. */
-};
-
-/*
- * Information relating to memory regions including offsets to
- * addresses in host physical space.
- */
-struct virtio_memory_regions_hpa {
-	/* Base guest physical address of region. */
-	uint64_t	guest_phys_address;
-	/* End guest physical address of region. */
-	uint64_t	guest_phys_address_end;
-	/* Size of region. */
-	uint64_t	memory_size;
-	/* Offset of region for gpa to hpa translation. */
-	uint64_t	host_phys_addr_offset;
-};
-
-/*
- * Memory structure includes region and mapping information.
- */
-struct virtio_memory {
-	uint64_t			base_address;			/* Base QEMU userspace address of the memory file. */
-	uint64_t			mapped_address;			/* Mapped address of memory file base in our applications memory space. */
-	uint64_t			mapped_size;			/* Total size of memory file. */
-	uint32_t			nregions;				/* Number of memory regions. */
-	 /* Number of memory regions for gpa to hpa translation. */
-	uint32_t			nregions_hpa;
-	/* Memory region information for gpa to hpa translation. */
-	struct virtio_memory_regions_hpa  *regions_hpa;
-	/* Memory region information. */
-	struct virtio_memory_regions      regions[0];
-};
-
-/*
- * Device operations to add/remove device.
- */
-struct virtio_net_device_ops {
-	int (* new_device) 		(struct virtio_net *);	/* Add device. */
-	void (* destroy_device)	(volatile struct virtio_net *);	/* Remove device. */
-};
-
-int init_virtio_net(struct virtio_net_device_ops const * const);
-int deinit_virtio_net(void);
-
-struct vhost_net_device_ops const * get_virtio_net_callbacks(void);
-
-#endif /* _VIRTIO_NET_H_ */
diff --git a/lib/librte_vhost/eventfd_link/Makefile b/lib/librte_vhost/eventfd_link/Makefile
new file mode 100644
index 0000000..fc3927b
--- /dev/null
+++ b/lib/librte_vhost/eventfd_link/Makefile
@@ -0,0 +1,39 @@
+#   BSD LICENSE
+#
+#   Copyright(c) 2010-2014 Intel Corporation. All rights reserved.
+#   All rights reserved.
+#
+#   Redistribution and use in source and binary forms, with or without
+#   modification, are permitted provided that the following conditions
+#   are met:
+#
+#     * Redistributions of source code must retain the above copyright
+#       notice, this list of conditions and the following disclaimer.
+#     * Redistributions in binary form must reproduce the above copyright
+#       notice, this list of conditions and the following disclaimer in
+#       the documentation and/or other materials provided with the
+#       distribution.
+#     * Neither the name of Intel Corporation nor the names of its
+#       contributors may be used to endorse or promote products derived
+#       from this software without specific prior written permission.
+#
+#   THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+#   "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+#   LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+#   A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+#   OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+#   SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+#   LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+#   DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+#   THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+#   (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+#   OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+
+obj-m += eventfd_link.o
+
+
+all:
+	make -C /lib/modules/$(shell uname -r)/build M=$(PWD) modules
+
+clean:
+	make -C /lib/modules/$(shell uname -r)/build M=$(PWD) clean
diff --git a/lib/librte_vhost/eventfd_link/eventfd_link.c b/lib/librte_vhost/eventfd_link/eventfd_link.c
new file mode 100644
index 0000000..fc0653a
--- /dev/null
+++ b/lib/librte_vhost/eventfd_link/eventfd_link.c
@@ -0,0 +1,205 @@
+/*-
+ *  * GPL LICENSE SUMMARY
+ *  *
+ *  *   Copyright(c) 2010-2014 Intel Corporation. All rights reserved.
+ *  *
+ *  *   This program is free software; you can redistribute it and/or modify
+ *  *   it under the terms of version 2 of the GNU General Public License as
+ *  *   published by the Free Software Foundation.
+ *  *
+ *  *   This program is distributed in the hope that it will be useful, but
+ *  *   WITHOUT ANY WARRANTY; without even the implied warranty of
+ *  *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ *  *   General Public License for more details.
+ *  *
+ *  *   You should have received a copy of the GNU General Public License
+ *  *   along with this program; if not, write to the Free Software
+ *  *   Foundation, Inc., 51 Franklin St - Fifth Floor, Boston, MA 02110-1301 USA.
+ *  *   The full GNU General Public License is included in this distribution
+ *  *   in the file called LICENSE.GPL.
+ *  *
+ *  *   Contact Information:
+ *  *   Intel Corporation
+ *   */
+
+#include <linux/eventfd.h>
+#include <linux/miscdevice.h>
+#include <linux/module.h>
+#include <linux/moduleparam.h>
+#include <linux/rcupdate.h>
+#include <linux/file.h>
+#include <linux/slab.h>
+#include <linux/fs.h>
+#include <linux/mmu_context.h>
+#include <linux/sched.h>
+#include <asm/mmu_context.h>
+#include <linux/fdtable.h>
+
+#include "eventfd_link.h"
+
+
+/*
+ * get_files_struct is copied from fs/file.c
+ */
+struct files_struct *
+get_files_struct (struct task_struct *task)
+{
+	struct files_struct *files;
+
+	task_lock (task);
+	files = task->files;
+	if (files)
+		atomic_inc (&files->count);
+	task_unlock (task);
+
+	return files;
+}
+
+/*
+ * put_files_struct is extracted from fs/file.c
+ */
+void
+put_files_struct (struct files_struct *files)
+{
+	if (atomic_dec_and_test (&files->count))
+	{
+		BUG ();
+	}
+}
+
+
+static long
+eventfd_link_ioctl (struct file *f, unsigned int ioctl, unsigned long arg)
+{
+	void __user *argp = (void __user *) arg;
+	struct task_struct *task_target = NULL;
+	struct file *file;
+	struct files_struct *files;
+	struct fdtable *fdt;
+	struct eventfd_copy eventfd_copy;
+
+	switch (ioctl)
+	{
+		case EVENTFD_COPY:
+			if (copy_from_user (&eventfd_copy, argp, sizeof (struct eventfd_copy)))
+				return -EFAULT;
+
+			/*
+			 * Find the task struct for the target pid
+			 */
+			task_target =
+				pid_task (find_vpid (eventfd_copy.target_pid), PIDTYPE_PID);
+			if (task_target == NULL)
+			{
+				printk (KERN_DEBUG "Failed to get mem ctx for target pid\n");
+				return -EFAULT;
+			}
+
+			files = get_files_struct (current);
+			if (files == NULL)
+			{
+				printk (KERN_DEBUG "Failed to get files struct\n");
+				return -EFAULT;
+			}
+
+			rcu_read_lock ();
+			file = fcheck_files (files, eventfd_copy.source_fd);
+			if (file)
+			{
+				if (file->f_mode & FMODE_PATH
+						|| !atomic_long_inc_not_zero (&file->f_count))
+					file = NULL;
+			}
+			rcu_read_unlock ();
+			put_files_struct (files);
+
+			if (file == NULL)
+			{
+				printk (KERN_DEBUG "Failed to get file from source pid\n");
+				return 0;
+			}
+
+			/*
+			 * Release the existing eventfd in the source process
+			 */
+			spin_lock (&files->file_lock);
+			filp_close (file, files);
+			fdt = files_fdtable (files);
+			fdt->fd[eventfd_copy.source_fd] = NULL;
+			spin_unlock (&files->file_lock);
+
+			/*
+			 * Find the file struct associated with the target fd.
+			 */
+
+			files = get_files_struct (task_target);
+			if (files == NULL)
+			{
+				printk (KERN_DEBUG "Failed to get files struct\n");
+				return -EFAULT;
+			}
+
+			rcu_read_lock ();
+			file = fcheck_files (files, eventfd_copy.target_fd);
+			if (file)
+			{
+				if (file->f_mode & FMODE_PATH
+						|| !atomic_long_inc_not_zero (&file->f_count))
+					file = NULL;
+			}
+			rcu_read_unlock ();
+			put_files_struct (files);
+
+			if (file == NULL)
+			{
+				printk (KERN_DEBUG "Failed to get file from target pid\n");
+				return 0;
+			}
+
+
+			/*
+			 * Install the file struct from the target process into the
+			 * file desciptor of the source process,
+			 */
+
+			fd_install (eventfd_copy.source_fd, file);
+
+			return 0;
+
+		default:
+			return -ENOIOCTLCMD;
+	}
+}
+
+static const struct file_operations eventfd_link_fops = {
+	.owner = THIS_MODULE,
+	.unlocked_ioctl = eventfd_link_ioctl,
+};
+
+
+static struct miscdevice eventfd_link_misc = {
+	.name = "eventfd-link",
+	.fops = &eventfd_link_fops,
+};
+
+static int __init
+eventfd_link_init (void)
+{
+	return misc_register (&eventfd_link_misc);
+}
+
+module_init (eventfd_link_init);
+
+static void __exit
+eventfd_link_exit (void)
+{
+	misc_deregister (&eventfd_link_misc);
+}
+
+module_exit (eventfd_link_exit);
+
+MODULE_VERSION ("0.0.1");
+MODULE_LICENSE ("GPL v2");
+MODULE_AUTHOR ("Anthony Fee");
+MODULE_DESCRIPTION ("Link eventfd");
+MODULE_ALIAS ("devname:eventfd-link");
diff --git a/lib/librte_vhost/eventfd_link/eventfd_link.h b/lib/librte_vhost/eventfd_link/eventfd_link.h
new file mode 100644
index 0000000..a32a8dd
--- /dev/null
+++ b/lib/librte_vhost/eventfd_link/eventfd_link.h
@@ -0,0 +1,79 @@
+/*-
+ *  * This file is provided under a dual BSD/GPLv2 license.  When using or
+ *  *   redistributing this file, you may do so under either license.
+ *  *
+ *  *   GPL LICENSE SUMMARY
+ *  *
+ *  *   Copyright(c) 2010-2014 Intel Corporation. All rights reserved.
+ *  *
+ *  *   This program is free software; you can redistribute it and/or modify
+ *  *   it under the terms of version 2 of the GNU General Public License as
+ *  *   published by the Free Software Foundation.
+ *  *
+ *  *   This program is distributed in the hope that it will be useful, but
+ *  *   WITHOUT ANY WARRANTY; without even the implied warranty of
+ *  *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ *  *   General Public License for more details.
+ *  *
+ *  *   You should have received a copy of the GNU General Public License
+ *  *   along with this program; if not, write to the Free Software
+ *  *   Foundation, Inc., 51 Franklin St - Fifth Floor, Boston, MA 02110-1301 USA.
+ *  *   The full GNU General Public License is included in this distribution
+ *  *   in the file called LICENSE.GPL.
+ *  *
+ *  *   Contact Information:
+ *  *   Intel Corporation
+ *  *
+ *  *   BSD LICENSE
+ *  *
+ *  *   Copyright(c) 2010-2014 Intel Corporation. All rights reserved.
+ *  *   All rights reserved.
+ *  *
+ *  *   Redistribution and use in source and binary forms, with or without
+ *  *   modification, are permitted provided that the following conditions
+ *  *   are met:
+ *  *
+ *  *     * Redistributions of source code must retain the above copyright
+ *  *       notice, this list of conditions and the following disclaimer.
+ *  *     * Redistributions in binary form must reproduce the above copyright
+ *  *       notice, this list of conditions and the following disclaimer in
+ *  *       the documentation and/or other materials provided with the
+ *  *       distribution.
+ *  *     * Neither the name of Intel Corporation nor the names of its
+ *  *       contributors may be used to endorse or promote products derived
+ *  *       from this software without specific prior written permission.
+ *  *
+ *  *   THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ *  *   "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ *  *   LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+ *  *   A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+ *  *   OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+ *  *   SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+ *  *   LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+ *  *   DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+ *  *   THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ *  *   (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+ *  *   OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ *  *
+ *   */
+
+#ifndef _EVENTFD_LINK_H_
+#define _EVENTFD_LINK_H_
+
+/*
+ *	ioctl to copy an fd entry in calling process to an fd in a target process
+ */
+#define EVENTFD_COPY 1
+
+/*
+ *	arguements for the EVENTFD_COPY ioctl
+ */
+struct eventfd_copy {
+	// fd in the target pid
+    unsigned target_fd;
+	// fd in the calling pid
+    unsigned source_fd;
+	// pid of the target pid
+    pid_t target_pid;
+};
+#endif /* _EVENTFD_LINK_H_ */
diff --git a/lib/librte_vhost/libvirt/qemu-wrap.py b/lib/librte_vhost/libvirt/qemu-wrap.py
new file mode 100755
index 0000000..e2d68a0
--- /dev/null
+++ b/lib/librte_vhost/libvirt/qemu-wrap.py
@@ -0,0 +1,367 @@
+#!/usr/bin/python
+#/*
+# *   BSD LICENSE
+# *
+# *   Copyright(c) 2010-2014 Intel Corporation. All rights reserved.
+# *   All rights reserved.
+# *
+# *   Redistribution and use in source and binary forms, with or without
+# *   modification, are permitted provided that the following conditions
+# *   are met:
+# *
+# *     * Redistributions of source code must retain the above copyright
+# *       notice, this list of conditions and the following disclaimer.
+# *     * Redistributions in binary form must reproduce the above copyright
+# *       notice, this list of conditions and the following disclaimer in
+# *       the documentation and/or other materials provided with the
+# *       distribution.
+# *     * Neither the name of Intel Corporation nor the names of its
+# *       contributors may be used to endorse or promote products derived
+# *       from this software without specific prior written permission.
+# *
+# *   THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+# *   "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+# *   LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+# *   A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+# *   OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+# *   SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+# *   LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+# *   DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+# *   THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+# *   (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+# *   OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+# */
+
+#####################################################################
+# This script is designed to modify the call to the QEMU emulator
+# to support userspace vhost when starting a guest machine through
+# libvirt with vhost enabled. The steps to enable this are as follows
+# and should be run as root:
+#
+# 1. Place this script in a libvirtd's binary search PATH ($PATH)
+#    A good location would be in the same directory that the QEMU
+#    binary is located
+#
+# 2. Ensure that the script has the same owner/group and file
+#    permissions as the QEMU binary
+#
+# 3. Update the VM xml file using "virsh edit VM.xml"
+#
+#    3.a) Set the VM to use the launch script
+#
+#    	Set the emulator path contained in the
+#		<emulator><emulator/> tags
+#
+#    	e.g replace <emulator>/usr/bin/qemu-kvm<emulator/>
+#        with    <emulator>/usr/bin/qemu-wrap.py<emulator/>
+#
+#	 3.b) Set the VM's device's to use vhost-net offload
+#
+#		<interface type="network">
+#       	<model type="virtio"/>
+#       	<driver name="vhost"/>
+#		<interface/>
+#
+# 4. Enable libvirt to access our userpace device file by adding it to
+#    controllers cgroup for libvirtd using the following steps
+#
+#   4.a) In /etc/libvirt/qemu.conf add/edit the following lines:
+#         1) cgroup_controllers = [ ... "devices", ... ]
+#		  2) clear_emulator_capabilities = 0
+#         3) user = "root"
+#         4) group = "root"
+#         5) cgroup_device_acl = [
+#                "/dev/null", "/dev/full", "/dev/zero",
+#                "/dev/random", "/dev/urandom",
+#                "/dev/ptmx", "/dev/kvm", "/dev/kqemu",
+#                "/dev/rtc", "/dev/hpet", "/dev/net/tun",
+#                "/dev/<devbase-name>-<index>",
+#            ]
+#
+#   4.b) Disable SELinux or set to permissive mode
+#
+#   4.c) Mount cgroup device controller
+#        "mkdir /dev/cgroup"
+#        "mount -t cgroup none /dev/cgroup -o devices"
+#
+#   4.d) Set hugetlbfs_mount variable - ( Optional )
+#        VMs using userspace vhost must use hugepage backed
+#        memory. This can be enabled in the libvirt XML
+#        config by adding a memory backing section to the
+#        XML config e.g.
+#             <memoryBacking>
+#             <hugepages/>
+#             </memoryBacking>
+#        This memory backing section should be added after the
+#        <memory> and <currentMemory> sections. This will add
+#        flags "-mem-prealloc -mem-path <path>" to the QEMU
+#        command line. The hugetlbfs_mount variable can be used
+#        to override the default <path> passed through by libvirt.
+#
+#        if "-mem-prealloc" or "-mem-path <path>" are not passed
+#        through and a vhost device is detected then these options will
+#        be automatically added by this script. This script will detect
+#        the system hugetlbfs mount point to be used for <path>. The
+#        default <path> for this script can be overidden by the
+#        hugetlbfs_dir variable in the configuration section of this script.
+#
+#
+#   4.e) Restart the libvirtd system process
+#        e.g. on Fedora "systemctl restart libvirtd.service"
+#
+#
+#   4.f) Edit the Configuration Parameters section of this script
+#        to point to the correct emulator location and set any
+#        addition options
+#
+# The script modifies the libvirtd Qemu call by modifying/adding
+# options based on the configuration parameters below.
+# NOTE:
+#     emul_path and us_vhost_path must be set
+#     All other parameters are optional
+#####################################################################
+
+
+#############################################
+# Configuration Parameters
+#############################################
+#Path to QEMU binary
+emul_path = "/usr/local/bin/qemu-system-x86_64"
+
+#Path to userspace vhost device file
+# This filename should match the --dev-basename --dev-index parameters of
+# the command used to launch the userspace vhost sample application e.g.
+# if the sample app lauch command is:
+#    ./build/vhost-switch ..... --dev-basename usvhost --dev-index 1
+# then this variable should be set to:
+#   us_vhost_path = "/dev/usvhost-1"
+us_vhost_path = "/dev/usvhost-1"
+
+#List of additional user defined emulation options. These options will
+#be added to all Qemu calls
+emul_opts_user = []
+
+#List of additional user defined emulation options for vhost only.
+#These options will only be added to vhost enabled guests
+emul_opts_user_vhost = []
+
+#For all VHOST enabled VMs, the VM memory is preallocated from hugetlbfs
+# Set this variable to one to enable this option for all VMs
+use_huge_all = 0
+
+#Instead of autodetecting, override the hugetlbfs directory by setting
+#this variable
+hugetlbfs_dir = ""
+
+#############################################
+
+
+#############################################
+# ****** Do Not Modify Below this Line ******
+#############################################
+
+import sys, os, subprocess
+
+
+#List of open userspace vhost file descriptors
+fd_list = []
+
+#additional virtio device flags when using userspace vhost
+vhost_flags = [ "csum=off",
+                "gso=off",
+                "guest_tso4=off",
+                "guest_tso6=off",
+                "guest_ecn=off"
+              ]
+
+
+#############################################
+# Find the system hugefile mount point.
+# Note:
+# if multiple hugetlbfs mount points exist
+# then the first one found will be used
+#############################################
+def find_huge_mount():
+
+    if (len(hugetlbfs_dir)):
+        return hugetlbfs_dir
+
+    huge_mount = ""
+
+    if (os.access("/proc/mounts", os.F_OK)):
+        f = open("/proc/mounts", "r")
+        line = f.readline()
+        while line:
+            line_split = line.split(" ")
+            if line_split[2] == 'hugetlbfs':
+                huge_mount = line_split[1]
+                break
+            line = f.readline()
+    else:
+        print "/proc/mounts not found"
+        exit (1)
+
+    f.close
+    if len(huge_mount) == 0:
+        print "Failed to find hugetlbfs mount point"
+        exit (1)
+
+    return huge_mount
+
+
+#############################################
+# Get a userspace Vhost file descriptor
+#############################################
+def get_vhost_fd():
+
+    if (os.access(us_vhost_path, os.F_OK)):
+        fd = os.open( us_vhost_path, os.O_RDWR)
+    else:
+        print ("US-Vhost file %s not found" %us_vhost_path)
+        exit (1)
+
+    return fd
+
+
+#############################################
+# Check for vhostfd. if found then replace
+# with our own vhost fd and append any vhost
+# flags onto the end
+#############################################
+def modify_netdev_arg(arg):
+	
+    global fd_list
+    vhost_in_use = 0
+    s = ''
+    new_opts = []
+    netdev_opts = arg.split(",")
+
+    for opt in netdev_opts:
+        #check if vhost is used
+        if "vhost" == opt[:5]:
+            vhost_in_use = 1
+        else:
+            new_opts.append(opt)
+
+    #if using vhost append vhost options
+    if vhost_in_use == 1:
+        #append vhost on option
+        new_opts.append('vhost=on')
+        #append vhostfd ption
+        new_fd = get_vhost_fd()
+        new_opts.append('vhostfd=' + str(new_fd))
+        fd_list.append(new_fd)
+
+    #concatenate all options
+    for opt in new_opts:
+        if len(s) > 0:
+			s+=','
+
+        s+=opt
+
+    return s	
+
+
+#############################################
+# Main
+#############################################
+def main():
+
+    global fd_list
+    global vhost_in_use
+    new_args = []
+    num_cmd_args = len(sys.argv)
+    emul_call = ''
+    mem_prealloc_set = 0
+    mem_path_set = 0
+    num = 0;
+
+    #parse the parameters
+    while (num < num_cmd_args):
+        arg = sys.argv[num]
+
+		#Check netdev +1 parameter for vhostfd
+        if arg == '-netdev':
+            num_vhost_devs = len(fd_list)
+            new_args.append(arg)
+
+            num+=1
+            arg = sys.argv[num]
+            mod_arg = modify_netdev_arg(arg)
+            new_args.append(mod_arg)
+
+            #append vhost flags if this is a vhost device
+            # and -device is the next arg
+            # i.e -device -opt1,-opt2,...,-opt3,%vhost
+            if (num_vhost_devs < len(fd_list)):
+                num+=1
+                arg = sys.argv[num]
+                if arg == '-device':
+                    new_args.append(arg)
+                    num+=1
+                    new_arg = sys.argv[num]
+                    for flag in vhost_flags:
+                        new_arg = ''.join([new_arg,',',flag])
+                    new_args.append(new_arg)
+                else:
+                    new_args.append(arg)
+        elif arg == '-mem-prealloc':
+            mem_prealloc_set = 1
+            new_args.append(arg)
+        elif arg == '-mem-path':
+            mem_path_set = 1
+            new_args.append(arg)
+
+        else:
+            new_args.append(arg)
+
+        num+=1
+
+    #Set Qemu binary location
+    emul_call+=emul_path
+    emul_call+=" "
+
+    #Add prealloc mem options if using vhost and not already added
+    if ((len(fd_list) > 0) and (mem_prealloc_set == 0)):
+        emul_call += "-mem-prealloc "
+
+    #Add mempath mem options if using vhost and not already added
+    if ((len(fd_list) > 0) and (mem_path_set == 0)):
+        #Detect and add hugetlbfs mount point
+        mp = find_huge_mount()
+        mp = "".join(["-mem-path ", mp])
+        emul_call += mp
+        emul_call += " "
+
+
+    #add user options
+    for opt in emul_opts_user:
+        emul_call += opt
+        emul_call += " "
+
+    #Add add user vhost only options
+    if len(fd_list) > 0:
+        for opt in emul_opts_user_vhost:
+            emul_call += opt
+            emul_call += " "
+
+    #Add updated libvirt options
+    iter_args = iter(new_args)
+    #skip 1st arg i.e. call to this script
+    next(iter_args)
+    for arg in iter_args:
+        emul_call+=str(arg)
+        emul_call+= " "
+
+    #Call QEMU
+    subprocess.call(emul_call, shell=True)
+
+
+    #Close usvhost files
+    for fd in fd_list:
+        os.close(fd)
+
+
+if __name__ == "__main__":
+    main()
+
diff --git a/lib/librte_vhost/main.c b/lib/librte_vhost/main.c
new file mode 100644
index 0000000..85ee8b8
--- /dev/null
+++ b/lib/librte_vhost/main.c
@@ -0,0 +1,3725 @@
+/*-
+ *   BSD LICENSE
+ *
+ *   Copyright(c) 2010-2014 Intel Corporation. All rights reserved.
+ *   All rights reserved.
+ *
+ *   Redistribution and use in source and binary forms, with or without
+ *   modification, are permitted provided that the following conditions
+ *   are met:
+ *
+ *     * Redistributions of source code must retain the above copyright
+ *       notice, this list of conditions and the following disclaimer.
+ *     * Redistributions in binary form must reproduce the above copyright
+ *       notice, this list of conditions and the following disclaimer in
+ *       the documentation and/or other materials provided with the
+ *       distribution.
+ *     * Neither the name of Intel Corporation nor the names of its
+ *       contributors may be used to endorse or promote products derived
+ *       from this software without specific prior written permission.
+ *
+ *   THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ *   "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ *   LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+ *   A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+ *   OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+ *   SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+ *   LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+ *   DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+ *   THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ *   (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+ *   OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#include <arpa/inet.h>
+#include <getopt.h>
+#include <linux/if_ether.h>
+#include <linux/if_vlan.h>
+#include <linux/virtio_net.h>
+#include <linux/virtio_ring.h>
+#include <signal.h>
+#include <stdint.h>
+#include <sys/eventfd.h>
+#include <sys/param.h>
+#include <unistd.h>
+
+#include <rte_atomic.h>
+#include <rte_cycles.h>
+#include <rte_ethdev.h>
+#include <rte_log.h>
+#include <rte_string_fns.h>
+#include <rte_malloc.h>
+
+#include "main.h"
+#include "virtio-net.h"
+#include "vhost-net-cdev.h"
+
+#define MAX_QUEUES 128
+
+/* the maximum number of external ports supported */
+#define MAX_SUP_PORTS 1
+
+/*
+ * Calculate the number of buffers needed per port
+ */
+#define NUM_MBUFS_PER_PORT ((MAX_QUEUES*RTE_TEST_RX_DESC_DEFAULT) +  		\
+							(num_switching_cores*MAX_PKT_BURST) +  			\
+							(num_switching_cores*RTE_TEST_TX_DESC_DEFAULT) +\
+							(num_switching_cores*MBUF_CACHE_SIZE))
+
+#define MBUF_CACHE_SIZE 128
+#define MBUF_SIZE (2048 + sizeof(struct rte_mbuf) + RTE_PKTMBUF_HEADROOM)
+
+/*
+ * No frame data buffer allocated from host are required for zero copy
+ * implementation, guest will allocate the frame data buffer, and vhost
+ * directly use it.
+ */
+#define VIRTIO_DESCRIPTOR_LEN_ZCP 1518
+#define MBUF_SIZE_ZCP (VIRTIO_DESCRIPTOR_LEN_ZCP + sizeof(struct rte_mbuf) \
+	+ RTE_PKTMBUF_HEADROOM)
+#define MBUF_CACHE_SIZE_ZCP 0
+
+/*
+ * RX and TX Prefetch, Host, and Write-back threshold values should be
+ * carefully set for optimal performance. Consult the network
+ * controller's datasheet and supporting DPDK documentation for guidance
+ * on how these parameters should be set.
+ */
+#define RX_PTHRESH 8 /* Default values of RX prefetch threshold reg. */
+#define RX_HTHRESH 8 /* Default values of RX host threshold reg. */
+#define RX_WTHRESH 4 /* Default values of RX write-back threshold reg. */
+
+/*
+ * These default values are optimized for use with the Intel(R) 82599 10 GbE
+ * Controller and the DPDK ixgbe PMD. Consider using other values for other
+ * network controllers and/or network drivers.
+ */
+#define TX_PTHRESH 36 /* Default values of TX prefetch threshold reg. */
+#define TX_HTHRESH 0  /* Default values of TX host threshold reg. */
+#define TX_WTHRESH 0  /* Default values of TX write-back threshold reg. */
+
+#define MAX_PKT_BURST 32 		/* Max burst size for RX/TX */
+#define MAX_MRG_PKT_BURST 16 	/* Max burst for merge buffers. Set to 1 due to performance issue. */
+#define BURST_TX_DRAIN_US 100 	/* TX drain every ~100us */
+
+#define BURST_RX_WAIT_US 15 	/* Defines how long we wait between retries on RX */
+#define BURST_RX_RETRIES 4		/* Number of retries on RX. */
+
+#define JUMBO_FRAME_MAX_SIZE    0x2600
+
+/* State of virtio device. */
+#define DEVICE_MAC_LEARNING 0
+#define DEVICE_RX			1
+#define DEVICE_SAFE_REMOVE	2
+
+/* Config_core_flag status definitions. */
+#define REQUEST_DEV_REMOVAL 1
+#define ACK_DEV_REMOVAL 0
+
+/* Configurable number of RX/TX ring descriptors */
+#define RTE_TEST_RX_DESC_DEFAULT 1024
+#define RTE_TEST_TX_DESC_DEFAULT 512
+
+/*
+ * Need refine these 2 macros for legacy and DPDK based front end:
+ * Max vring avail descriptor/entries from guest - MAX_PKT_BURST
+ * And then adjust power 2.
+ */
+/*
+ * For legacy front end, 128 descriptors,
+ * half for virtio header, another half for mbuf.
+ */
+#define RTE_TEST_RX_DESC_DEFAULT_ZCP 32   /* legacy: 32, DPDK virt FE: 128. */
+#define RTE_TEST_TX_DESC_DEFAULT_ZCP 64   /* legacy: 64, DPDK virt FE: 64.  */
+
+/* Get first 4 bytes in mbuf headroom. */
+#define MBUF_HEADROOM_UINT32(mbuf) (*(uint32_t *)((uint8_t *)(mbuf) \
+		+ sizeof(struct rte_mbuf)))
+
+/* true if x is a power of 2 */
+#define POWEROF2(x) ((((x)-1) & (x)) == 0)
+
+#define INVALID_PORT_ID 0xFF
+
+/* Max number of devices. Limited by vmdq. */
+#define MAX_DEVICES 64
+
+/* Size of buffers used for snprintfs. */
+#define MAX_PRINT_BUFF 6072
+
+/* Maximum character device basename size. */
+#define MAX_BASENAME_SZ 10
+
+/* Maximum long option length for option parsing. */
+#define MAX_LONG_OPT_SZ 64
+
+/* Used to compare MAC addresses. */
+#define MAC_ADDR_CMP 0xFFFFFFFFFFFFULL
+
+/* Number of descriptors per cacheline. */
+#define DESC_PER_CACHELINE (CACHE_LINE_SIZE / sizeof(struct vring_desc))
+
+/* mask of enabled ports */
+static uint32_t enabled_port_mask = 0;
+
+/*Number of switching cores enabled*/
+static uint32_t num_switching_cores = 0;
+
+/* number of devices/queues to support*/
+static uint32_t num_queues = 0;
+uint32_t num_devices = 0;
+
+/*
+ * Enable zero copy, pkts buffer will directly dma to hw descriptor,
+ * disabled on default.
+ */
+static uint32_t zero_copy;
+
+/* number of descriptors to apply*/
+static uint32_t num_rx_descriptor = RTE_TEST_RX_DESC_DEFAULT_ZCP;
+static uint32_t num_tx_descriptor = RTE_TEST_TX_DESC_DEFAULT_ZCP;
+
+/* max ring descriptor, ixgbe, i40e, e1000 all are 4096. */
+#define MAX_RING_DESC 4096
+
+struct vpool {
+	struct rte_mempool *pool;
+	struct rte_ring *ring;
+	uint32_t buf_size;
+} vpool_array[MAX_QUEUES+MAX_QUEUES];
+
+/* Enable VM2VM communications. If this is disabled then the MAC address compare is skipped. */
+typedef enum {
+	VM2VM_DISABLED = 0,
+	VM2VM_SOFTWARE = 1,
+	VM2VM_HARDWARE = 2,
+	VM2VM_LAST
+} vm2vm_type;
+static vm2vm_type vm2vm_mode = VM2VM_SOFTWARE;
+
+/* The type of host physical address translated from guest physical address. */
+typedef enum {
+	PHYS_ADDR_CONTINUOUS = 0,
+	PHYS_ADDR_CROSS_SUBREG = 1,
+	PHYS_ADDR_INVALID = 2,
+	PHYS_ADDR_LAST
+} hpa_type;
+
+/* Enable stats. */
+static uint32_t enable_stats = 0;
+/* Enable retries on RX. */
+static uint32_t enable_retry = 1;
+/* Specify timeout (in useconds) between retries on RX. */
+static uint32_t burst_rx_delay_time = BURST_RX_WAIT_US;
+/* Specify the number of retries on RX. */
+static uint32_t burst_rx_retry_num = BURST_RX_RETRIES;
+
+/* Character device basename. Can be set by user. */
+static char dev_basename[MAX_BASENAME_SZ] = "vhost-net";
+
+/* Charater device index. Can be set by user. */
+static uint32_t dev_index = 0;
+
+/* This can be set by the user so it is made available here. */
+extern uint64_t VHOST_FEATURES;
+
+/* Default configuration for rx and tx thresholds etc. */
+static struct rte_eth_rxconf rx_conf_default = {
+	.rx_thresh = {
+		.pthresh = RX_PTHRESH,
+		.hthresh = RX_HTHRESH,
+		.wthresh = RX_WTHRESH,
+	},
+	.rx_drop_en = 1,
+};
+
+/*
+ * These default values are optimized for use with the Intel(R) 82599 10 GbE
+ * Controller and the DPDK ixgbe/igb PMD. Consider using other values for other
+ * network controllers and/or network drivers.
+ */
+static struct rte_eth_txconf tx_conf_default = {
+	.tx_thresh = {
+		.pthresh = TX_PTHRESH,
+		.hthresh = TX_HTHRESH,
+		.wthresh = TX_WTHRESH,
+	},
+	.tx_free_thresh = 0, /* Use PMD default values */
+	.tx_rs_thresh = 0, /* Use PMD default values */
+};
+
+/* empty vmdq configuration structure. Filled in programatically */
+static struct rte_eth_conf vmdq_conf_default = {
+	.rxmode = {
+		.mq_mode        = ETH_MQ_RX_VMDQ_ONLY,
+		.split_hdr_size = 0,
+		.header_split   = 0, /**< Header Split disabled */
+		.hw_ip_checksum = 0, /**< IP checksum offload disabled */
+		.hw_vlan_filter = 0, /**< VLAN filtering disabled */
+		/*
+		 * It is necessary for 1G NIC such as I350,
+		 * this fixes bug of ipv4 forwarding in guest can't
+		 * forward pakets from one virtio dev to another virtio dev.
+		 */
+		.hw_vlan_strip  = 1, /**< VLAN strip enabled. */
+		.jumbo_frame    = 0, /**< Jumbo Frame Support disabled */
+		.hw_strip_crc   = 0, /**< CRC stripped by hardware */
+	},
+
+	.txmode = {
+		.mq_mode = ETH_MQ_TX_NONE,
+	},
+	.rx_adv_conf = {
+		/*
+		 * should be overridden separately in code with
+		 * appropriate values
+		 */
+		.vmdq_rx_conf = {
+			.nb_queue_pools = ETH_8_POOLS,
+			.enable_default_pool = 0,
+			.default_pool = 0,
+			.nb_pool_maps = 0,
+			.pool_map = {{0, 0},},
+		},
+	},
+};
+
+static unsigned lcore_ids[RTE_MAX_LCORE];
+static uint8_t ports[RTE_MAX_ETHPORTS];
+static unsigned num_ports = 0; /**< The number of ports specified in command line */
+
+static const uint16_t external_pkt_default_vlan_tag = 2000;
+const uint16_t vlan_tags[] = {
+	1000, 1001, 1002, 1003, 1004, 1005, 1006, 1007,
+	1008, 1009, 1010, 1011,	1012, 1013, 1014, 1015,
+	1016, 1017, 1018, 1019, 1020, 1021, 1022, 1023,
+	1024, 1025, 1026, 1027, 1028, 1029, 1030, 1031,
+	1032, 1033, 1034, 1035, 1036, 1037, 1038, 1039,
+	1040, 1041, 1042, 1043, 1044, 1045, 1046, 1047,
+	1048, 1049, 1050, 1051, 1052, 1053, 1054, 1055,
+	1056, 1057, 1058, 1059, 1060, 1061, 1062, 1063,
+};
+
+/* ethernet addresses of ports */
+static struct ether_addr vmdq_ports_eth_addr[RTE_MAX_ETHPORTS];
+
+/* heads for the main used and free linked lists for the data path. */
+static struct virtio_net_data_ll *ll_root_used = NULL;
+static struct virtio_net_data_ll *ll_root_free = NULL;
+
+/* Array of data core structures containing information on individual core linked lists. */
+static struct lcore_info lcore_info[RTE_MAX_LCORE];
+
+/* Used for queueing bursts of TX packets. */
+struct mbuf_table {
+	unsigned len;
+	unsigned txq_id;
+	struct rte_mbuf *m_table[MAX_PKT_BURST];
+};
+
+/* TX queue for each data core. */
+struct mbuf_table lcore_tx_queue[RTE_MAX_LCORE];
+
+/* TX queue fori each virtio device for zero copy. */
+struct mbuf_table tx_queue_zcp[MAX_QUEUES];
+
+/* Vlan header struct used to insert vlan tags on TX. */
+struct vlan_ethhdr {
+	unsigned char   h_dest[ETH_ALEN];
+	unsigned char   h_source[ETH_ALEN];
+	__be16          h_vlan_proto;
+	__be16          h_vlan_TCI;
+	__be16          h_vlan_encapsulated_proto;
+};
+
+/* IPv4 Header */
+struct ipv4_hdr {
+	uint8_t  version_ihl;		/**< version and header length */
+	uint8_t  type_of_service;	/**< type of service */
+	uint16_t total_length;		/**< length of packet */
+	uint16_t packet_id;		/**< packet ID */
+	uint16_t fragment_offset;	/**< fragmentation offset */
+	uint8_t  time_to_live;		/**< time to live */
+	uint8_t  next_proto_id;		/**< protocol ID */
+	uint16_t hdr_checksum;		/**< header checksum */
+	uint32_t src_addr;		/**< source address */
+	uint32_t dst_addr;		/**< destination address */
+} __attribute__((__packed__));
+
+/* Header lengths. */
+#define VLAN_HLEN       4
+#define VLAN_ETH_HLEN   18
+
+/* Per-device statistics struct */
+struct device_statistics {
+	uint64_t tx_total;
+	rte_atomic64_t rx_total_atomic;
+	uint64_t rx_total;
+	uint64_t tx;
+	rte_atomic64_t rx_atomic;
+	uint64_t rx;
+} __rte_cache_aligned;
+struct device_statistics dev_statistics[MAX_DEVICES];
+
+/*
+ * Builds up the correct configuration for VMDQ VLAN pool map
+ * according to the pool & queue limits.
+ */
+static inline int
+get_eth_conf(struct rte_eth_conf *eth_conf, uint32_t num_devices)
+{
+	struct rte_eth_vmdq_rx_conf conf;
+	unsigned i;
+
+	memset(&conf, 0, sizeof(conf));
+	conf.nb_queue_pools = (enum rte_eth_nb_pools)num_devices;
+	conf.nb_pool_maps = num_devices;
+	conf.enable_loop_back =
+		vmdq_conf_default.rx_adv_conf.vmdq_rx_conf.enable_loop_back;
+
+	for (i = 0; i < conf.nb_pool_maps; i++) {
+		conf.pool_map[i].vlan_id = vlan_tags[ i ];
+		conf.pool_map[i].pools = (1UL << i);
+	}
+
+	(void)(rte_memcpy(eth_conf, &vmdq_conf_default, sizeof(*eth_conf)));
+	(void)(rte_memcpy(&eth_conf->rx_adv_conf.vmdq_rx_conf, &conf,
+		   sizeof(eth_conf->rx_adv_conf.vmdq_rx_conf)));
+	return 0;
+}
+
+/*
+ * Validate the device number according to the max pool number gotten form
+ * dev_info. If the device number is invalid, give the error message and
+ * return -1. Each device must have its own pool.
+ */
+static inline int
+validate_num_devices(uint32_t max_nb_devices)
+{
+	if (num_devices > max_nb_devices) {
+		RTE_LOG(ERR, VHOST_PORT, "invalid number of devices\n");
+		return -1;
+	}
+	return 0;
+}
+
+/*
+ * Initialises a given port using global settings and with the rx buffers
+ * coming from the mbuf_pool passed as parameter
+ */
+static inline int
+port_init(uint8_t port)
+{
+	struct rte_eth_dev_info dev_info;
+	struct rte_eth_conf port_conf;
+	uint16_t rx_rings, tx_rings;
+	uint16_t rx_ring_size, tx_ring_size;
+	int retval;
+	uint16_t q;
+
+	/* The max pool number from dev_info will be used to validate the pool number specified in cmd line */
+	rte_eth_dev_info_get (port, &dev_info);
+
+	/*configure the number of supported virtio devices based on VMDQ limits */
+	num_devices = dev_info.max_vmdq_pools;
+	num_queues = dev_info.max_rx_queues;
+
+	if (zero_copy) {
+		rx_ring_size = num_rx_descriptor;
+		tx_ring_size = num_tx_descriptor;
+		tx_rings = dev_info.max_tx_queues;
+	} else {
+		rx_ring_size = RTE_TEST_RX_DESC_DEFAULT;
+		tx_ring_size = RTE_TEST_TX_DESC_DEFAULT;
+		tx_rings = (uint16_t)rte_lcore_count();
+	}
+
+	retval = validate_num_devices(MAX_DEVICES);
+	if (retval < 0)
+		return retval;
+
+	/* Get port configuration. */
+	retval = get_eth_conf(&port_conf, num_devices);
+	if (retval < 0)
+		return retval;
+
+	if (port >= rte_eth_dev_count()) return -1;
+
+	rx_rings = (uint16_t)num_queues,
+	/* Configure ethernet device. */
+	retval = rte_eth_dev_configure(port, rx_rings, tx_rings, &port_conf);
+	if (retval != 0)
+		return retval;
+
+	/* Setup the queues. */
+	for (q = 0; q < rx_rings; q ++) {
+		retval = rte_eth_rx_queue_setup(port, q, rx_ring_size,
+						rte_eth_dev_socket_id(port), &rx_conf_default,
+						vpool_array[q].pool);
+		if (retval < 0)
+			return retval;
+	}
+	for (q = 0; q < tx_rings; q ++) {
+		retval = rte_eth_tx_queue_setup(port, q, tx_ring_size,
+						rte_eth_dev_socket_id(port), &tx_conf_default);
+		if (retval < 0)
+			return retval;
+	}
+
+	/* Start the device. */
+	retval  = rte_eth_dev_start(port);
+	if (retval < 0) {
+		RTE_LOG(ERR, VHOST_DATA, "Failed to start the device.\n");
+		return retval;
+	}
+
+	rte_eth_macaddr_get(port, &vmdq_ports_eth_addr[port]);
+	RTE_LOG(INFO, VHOST_PORT, "Max virtio devices supported: %u\n", num_devices);
+	RTE_LOG(INFO, VHOST_PORT, "Port %u MAC: %02"PRIx8" %02"PRIx8" %02"PRIx8
+			" %02"PRIx8" %02"PRIx8" %02"PRIx8"\n",
+			(unsigned)port,
+			vmdq_ports_eth_addr[port].addr_bytes[0],
+			vmdq_ports_eth_addr[port].addr_bytes[1],
+			vmdq_ports_eth_addr[port].addr_bytes[2],
+			vmdq_ports_eth_addr[port].addr_bytes[3],
+			vmdq_ports_eth_addr[port].addr_bytes[4],
+			vmdq_ports_eth_addr[port].addr_bytes[5]);
+
+	return 0;
+}
+
+/*
+ * Set character device basename.
+ */
+static int
+us_vhost_parse_basename(const char *q_arg)
+{
+	/* parse number string */
+
+	if (strnlen(q_arg, MAX_BASENAME_SZ) > MAX_BASENAME_SZ)
+		return -1;
+	else
+		snprintf((char*)&dev_basename, MAX_BASENAME_SZ, "%s", q_arg);
+
+	return 0;
+}
+
+/*
+ * Parse the portmask provided at run time.
+ */
+static int
+parse_portmask(const char *portmask)
+{
+	char *end = NULL;
+	unsigned long pm;
+
+	errno = 0;
+
+	/* parse hexadecimal string */
+	pm = strtoul(portmask, &end, 16);
+	if ((portmask[0] == '\0') || (end == NULL) || (*end != '\0') || (errno != 0))
+		return -1;
+
+	if (pm == 0)
+		return -1;
+
+	return pm;
+
+}
+
+/*
+ * Parse num options at run time.
+ */
+static int
+parse_num_opt(const char *q_arg, uint32_t max_valid_value)
+{
+	char *end = NULL;
+	unsigned long num;
+
+	errno = 0;
+
+	/* parse unsigned int string */
+	num = strtoul(q_arg, &end, 10);
+	if ((q_arg[0] == '\0') || (end == NULL) || (*end != '\0') || (errno != 0))
+		return -1;
+
+	if (num > max_valid_value)
+		return -1;
+
+	return num;
+
+}
+
+/*
+ * Display usage
+ */
+static void
+us_vhost_usage(const char *prgname)
+{
+	RTE_LOG(INFO, VHOST_CONFIG, "%s [EAL options] -- -p PORTMASK\n"
+	"		--vm2vm [0|1|2]\n"
+	"		--rx_retry [0|1] --mergeable [0|1] --stats [0-N]\n"
+	"		--dev-basename <name> --dev-index [0-N]\n"
+	"		--nb-devices ND\n"
+	"		-p PORTMASK: Set mask for ports to be used by application\n"
+	"		--vm2vm [0|1|2]: disable/software(default)/hardware vm2vm comms\n"
+	"		--rx-retry [0|1]: disable/enable(default) retries on rx. Enable retry if destintation queue is full\n"
+	"		--rx-retry-delay [0-N]: timeout(in usecond) between retries on RX. This makes effect only if retries on rx enabled\n"
+	"		--rx-retry-num [0-N]: the number of retries on rx. This makes effect only if retries on rx enabled\n"
+	"		--mergeable [0|1]: disable(default)/enable RX mergeable buffers\n"
+	"		--stats [0-N]: 0: Disable stats, N: Time in seconds to print stats\n"
+	"		--dev-basename: The basename to be used for the character device.\n"
+	"		--dev-index [0-N]: Defaults to zero if not used. Index is appended to basename.\n"
+	"		--zero-copy [0|1]: disable(default)/enable rx/tx "
+			"zero copy\n"
+	"		--rx-desc-num [0-N]: the number of descriptors on rx, "
+			"used only when zero copy is enabled.\n"
+	"		--tx-desc-num [0-N]: the number of descriptors on tx, "
+			"used only when zero copy is enabled.\n",
+	       prgname);
+}
+
+/*
+ * Parse the arguments given in the command line of the application.
+ */
+static int
+us_vhost_parse_args(int argc, char **argv)
+{
+	int opt, ret;
+	int option_index;
+	unsigned i;
+	const char *prgname = argv[0];
+	static struct option long_option[] = {
+		{"vm2vm", required_argument, NULL, 0},
+		{"rx-retry", required_argument, NULL, 0},
+		{"rx-retry-delay", required_argument, NULL, 0},
+		{"rx-retry-num", required_argument, NULL, 0},
+		{"mergeable", required_argument, NULL, 0},
+		{"stats", required_argument, NULL, 0},
+		{"dev-basename", required_argument, NULL, 0},
+		{"dev-index", required_argument, NULL, 0},
+		{"zero-copy", required_argument, NULL, 0},
+		{"rx-desc-num", required_argument, NULL, 0},
+		{"tx-desc-num", required_argument, NULL, 0},
+		{NULL, 0, 0, 0},
+	};
+
+	/* Parse command line */
+	while ((opt = getopt_long(argc, argv, "p:",long_option, &option_index)) != EOF) {
+		switch (opt) {
+		/* Portmask */
+		case 'p':
+			enabled_port_mask = parse_portmask(optarg);
+			if (enabled_port_mask == 0) {
+				RTE_LOG(INFO, VHOST_CONFIG, "Invalid portmask\n");
+				us_vhost_usage(prgname);
+				return -1;
+			}
+			break;
+
+		case 0:
+			/* Enable/disable vm2vm comms. */
+			if (!strncmp(long_option[option_index].name, "vm2vm",
+				MAX_LONG_OPT_SZ)) {
+				ret = parse_num_opt(optarg, (VM2VM_LAST - 1));
+				if (ret == -1) {
+					RTE_LOG(INFO, VHOST_CONFIG,
+						"Invalid argument for "
+						"vm2vm [0|1|2]\n");
+					us_vhost_usage(prgname);
+					return -1;
+				} else {
+					vm2vm_mode = (vm2vm_type)ret;
+				}
+			}
+
+			/* Enable/disable retries on RX. */
+			if (!strncmp(long_option[option_index].name, "rx-retry", MAX_LONG_OPT_SZ)) {
+				ret = parse_num_opt(optarg, 1);
+				if (ret == -1) {
+					RTE_LOG(INFO, VHOST_CONFIG, "Invalid argument for rx-retry [0|1]\n");
+					us_vhost_usage(prgname);
+					return -1;
+				} else {
+					enable_retry = ret;
+				}
+			}
+
+			/* Specify the retries delay time (in useconds) on RX. */
+			if (!strncmp(long_option[option_index].name, "rx-retry-delay", MAX_LONG_OPT_SZ)) {
+				ret = parse_num_opt(optarg, INT32_MAX);
+				if (ret == -1) {
+					RTE_LOG(INFO, VHOST_CONFIG, "Invalid argument for rx-retry-delay [0-N]\n");
+					us_vhost_usage(prgname);
+					return -1;
+				} else {
+					burst_rx_delay_time = ret;
+				}
+			}
+
+			/* Specify the retries number on RX. */
+			if (!strncmp(long_option[option_index].name, "rx-retry-num", MAX_LONG_OPT_SZ)) {
+				ret = parse_num_opt(optarg, INT32_MAX);
+				if (ret == -1) {
+					RTE_LOG(INFO, VHOST_CONFIG, "Invalid argument for rx-retry-num [0-N]\n");
+					us_vhost_usage(prgname);
+					return -1;
+				} else {
+					burst_rx_retry_num = ret;
+				}
+			}
+
+			/* Enable/disable RX mergeable buffers. */
+			if (!strncmp(long_option[option_index].name, "mergeable", MAX_LONG_OPT_SZ)) {
+				ret = parse_num_opt(optarg, 1);
+				if (ret == -1) {
+					RTE_LOG(INFO, VHOST_CONFIG, "Invalid argument for mergeable [0|1]\n");
+					us_vhost_usage(prgname);
+					return -1;
+				} else {
+					if (ret) {
+						vmdq_conf_default.rxmode.jumbo_frame = 1;
+						vmdq_conf_default.rxmode.max_rx_pkt_len
+							= JUMBO_FRAME_MAX_SIZE;
+						VHOST_FEATURES = (1ULL << VIRTIO_NET_F_MRG_RXBUF);
+					}
+				}
+			}
+
+			/* Enable/disable stats. */
+			if (!strncmp(long_option[option_index].name, "stats", MAX_LONG_OPT_SZ)) {
+				ret = parse_num_opt(optarg, INT32_MAX);
+				if (ret == -1) {
+					RTE_LOG(INFO, VHOST_CONFIG, "Invalid argument for stats [0..N]\n");
+					us_vhost_usage(prgname);
+					return -1;
+				} else {
+					enable_stats = ret;
+				}
+			}
+
+			/* Set character device basename. */
+			if (!strncmp(long_option[option_index].name, "dev-basename", MAX_LONG_OPT_SZ)) {
+				if (us_vhost_parse_basename(optarg) == -1) {
+					RTE_LOG(INFO, VHOST_CONFIG, "Invalid argument for character device basename (Max %d characters)\n", MAX_BASENAME_SZ);
+					us_vhost_usage(prgname);
+					return -1;
+				}
+			}
+
+			/* Set character device index. */
+			if (!strncmp(long_option[option_index].name, "dev-index", MAX_LONG_OPT_SZ)) {
+				ret = parse_num_opt(optarg, INT32_MAX);
+				if (ret == -1) {
+					RTE_LOG(INFO, VHOST_CONFIG, "Invalid argument for character device index [0..N]\n");
+					us_vhost_usage(prgname);
+					return -1;
+				} else
+					dev_index = ret;
+			}
+
+			/* Enable/disable rx/tx zero copy. */
+			if (!strncmp(long_option[option_index].name,
+				"zero-copy", MAX_LONG_OPT_SZ)) {
+				ret = parse_num_opt(optarg, 1);
+				if (ret == -1) {
+					RTE_LOG(INFO, VHOST_CONFIG,
+						"Invalid argument"
+						" for zero-copy [0|1]\n");
+					us_vhost_usage(prgname);
+					return -1;
+				} else
+					zero_copy = ret;
+
+				if (zero_copy) {
+#ifdef RTE_MBUF_REFCNT
+					RTE_LOG(ERR, VHOST_CONFIG, "Before running "
+					"zero copy vhost APP, please "
+					"disable RTE_MBUF_REFCNT\n"
+					"in config file and then rebuild DPDK "
+					"core lib!\n"
+					"Otherwise please disable zero copy "
+					"flag in command line!\n");
+					return -1;
+#endif
+				}
+			}
+
+			/* Specify the descriptor number on RX. */
+			if (!strncmp(long_option[option_index].name,
+				"rx-desc-num", MAX_LONG_OPT_SZ)) {
+				ret = parse_num_opt(optarg, MAX_RING_DESC);
+				if ((ret == -1) || (!POWEROF2(ret))) {
+					RTE_LOG(INFO, VHOST_CONFIG,
+					"Invalid argument for rx-desc-num[0-N],"
+					"power of 2 required.\n");
+					us_vhost_usage(prgname);
+					return -1;
+				} else {
+					num_rx_descriptor = ret;
+				}
+			}
+
+			/* Specify the descriptor number on TX. */
+			if (!strncmp(long_option[option_index].name,
+				"tx-desc-num", MAX_LONG_OPT_SZ)) {
+				ret = parse_num_opt(optarg, MAX_RING_DESC);
+				if ((ret == -1) || (!POWEROF2(ret))) {
+					RTE_LOG(INFO, VHOST_CONFIG,
+					"Invalid argument for tx-desc-num [0-N],"
+					"power of 2 required.\n");
+					us_vhost_usage(prgname);
+					return -1;
+				} else {
+					num_tx_descriptor = ret;
+				}
+			}
+
+			break;
+
+			/* Invalid option - print options. */
+		default:
+			us_vhost_usage(prgname);
+			return -1;
+		}
+	}
+
+	for (i = 0; i < RTE_MAX_ETHPORTS; i++) {
+		if (enabled_port_mask & (1 << i))
+			ports[num_ports++] = (uint8_t)i;
+	}
+
+	if ((num_ports ==  0) || (num_ports > MAX_SUP_PORTS)) {
+		RTE_LOG(INFO, VHOST_PORT, "Current enabled port number is %u,"
+			"but only %u port can be enabled\n",num_ports, MAX_SUP_PORTS);
+		return -1;
+	}
+
+	if ((zero_copy == 1) && (vm2vm_mode == VM2VM_SOFTWARE)) {
+		RTE_LOG(INFO, VHOST_PORT,
+			"Vhost zero copy doesn't support software vm2vm,"
+			"please specify 'vm2vm 2' to use hardware vm2vm.\n");
+		return -1;
+	}
+
+	if ((zero_copy == 1) && (vmdq_conf_default.rxmode.jumbo_frame == 1)) {
+		RTE_LOG(INFO, VHOST_PORT,
+			"Vhost zero copy doesn't support jumbo frame,"
+			"please specify '--mergeable 0' to disable the "
+			"mergeable feature.\n");
+		return -1;
+	}
+
+	return 0;
+}
+
+/*
+ * Update the global var NUM_PORTS and array PORTS according to system ports number
+ * and return valid ports number
+ */
+static unsigned check_ports_num(unsigned nb_ports)
+{
+	unsigned valid_num_ports = num_ports;
+	unsigned portid;
+
+	if (num_ports > nb_ports) {
+		RTE_LOG(INFO, VHOST_PORT, "\nSpecified port number(%u) exceeds total system port number(%u)\n",
+			num_ports, nb_ports);
+		num_ports = nb_ports;
+	}
+
+	for (portid = 0; portid < num_ports; portid ++) {
+		if (ports[portid] >= nb_ports) {
+			RTE_LOG(INFO, VHOST_PORT, "\nSpecified port ID(%u) exceeds max system port ID(%u)\n",
+				ports[portid], (nb_ports - 1));
+			ports[portid] = INVALID_PORT_ID;
+			valid_num_ports--;
+		}
+	}
+	return valid_num_ports;
+}
+
+/*
+ * Macro to print out packet contents. Wrapped in debug define so that the
+ * data path is not effected when debug is disabled.
+ */
+#ifdef DEBUG
+#define PRINT_PACKET(device, addr, size, header) do {																\
+	char *pkt_addr = (char*)(addr);																					\
+	unsigned int index;																								\
+	char packet[MAX_PRINT_BUFF];																					\
+																													\
+	if ((header))																									\
+		snprintf(packet, MAX_PRINT_BUFF, "(%"PRIu64") Header size %d: ", (device->device_fh), (size));				\
+	else																											\
+		snprintf(packet, MAX_PRINT_BUFF, "(%"PRIu64") Packet size %d: ", (device->device_fh), (size));				\
+	for (index = 0; index < (size); index++) {																		\
+		snprintf(packet + strnlen(packet, MAX_PRINT_BUFF), MAX_PRINT_BUFF - strnlen(packet, MAX_PRINT_BUFF),	\
+			"%02hhx ", pkt_addr[index]);																			\
+	}																												\
+	snprintf(packet + strnlen(packet, MAX_PRINT_BUFF), MAX_PRINT_BUFF - strnlen(packet, MAX_PRINT_BUFF), "\n");	\
+																													\
+	LOG_DEBUG(VHOST_DATA, "%s", packet);																					\
+} while(0)
+#else
+#define PRINT_PACKET(device, addr, size, header) do{} while(0)
+#endif
+
+/*
+ * Function to convert guest physical addresses to vhost virtual addresses. This
+ * is used to convert virtio buffer addresses.
+ */
+static inline uint64_t __attribute__((always_inline))
+gpa_to_vva(struct virtio_net *dev, uint64_t guest_pa)
+{
+	struct virtio_memory_regions *region;
+	uint32_t regionidx;
+	uint64_t vhost_va = 0;
+
+	for (regionidx = 0; regionidx < dev->mem->nregions; regionidx++) {
+		region = &dev->mem->regions[regionidx];
+		if ((guest_pa >= region->guest_phys_address) &&
+			(guest_pa <= region->guest_phys_address_end)) {
+			vhost_va = region->address_offset + guest_pa;
+			break;
+		}
+	}
+	LOG_DEBUG(VHOST_DATA, "(%"PRIu64") GPA %p| VVA %p\n",
+		dev->device_fh, (void*)(uintptr_t)guest_pa, (void*)(uintptr_t)vhost_va);
+
+	return vhost_va;
+}
+
+/*
+ * Function to convert guest physical addresses to vhost physical addresses.
+ * This is used to convert virtio buffer addresses.
+ */
+static inline uint64_t __attribute__((always_inline))
+gpa_to_hpa(struct virtio_net *dev, uint64_t guest_pa,
+	uint32_t buf_len, hpa_type *addr_type)
+{
+	struct virtio_memory_regions_hpa *region;
+	uint32_t regionidx;
+	uint64_t vhost_pa = 0;
+
+	*addr_type = PHYS_ADDR_INVALID;
+
+	for (regionidx = 0; regionidx < dev->mem->nregions_hpa; regionidx++) {
+		region = &dev->mem->regions_hpa[regionidx];
+		if ((guest_pa >= region->guest_phys_address) &&
+			(guest_pa <= region->guest_phys_address_end)) {
+			vhost_pa = region->host_phys_addr_offset + guest_pa;
+			if (likely((guest_pa + buf_len - 1)
+				<= region->guest_phys_address_end))
+				*addr_type = PHYS_ADDR_CONTINUOUS;
+			else
+				*addr_type = PHYS_ADDR_CROSS_SUBREG;
+			break;
+		}
+	}
+
+	LOG_DEBUG(VHOST_DATA, "(%"PRIu64") GPA %p| HPA %p\n",
+		dev->device_fh, (void *)(uintptr_t)guest_pa,
+		(void *)(uintptr_t)vhost_pa);
+
+	return vhost_pa;
+}
+
+/*
+ * This function adds buffers to the virtio devices RX virtqueue. Buffers can
+ * be received from the physical port or from another virtio device. A packet
+ * count is returned to indicate the number of packets that were succesfully
+ * added to the RX queue. This function works when mergeable is disabled.
+ */
+static inline uint32_t __attribute__((always_inline))
+virtio_dev_rx(struct virtio_net *dev, struct rte_mbuf **pkts, uint32_t count)
+{
+	struct vhost_virtqueue *vq;
+	struct vring_desc *desc;
+	struct rte_mbuf *buff;
+	/* The virtio_hdr is initialised to 0. */
+	struct virtio_net_hdr_mrg_rxbuf virtio_hdr = {{0,0,0,0,0,0},0};
+	uint64_t buff_addr = 0;
+	uint64_t buff_hdr_addr = 0;
+	uint32_t head[MAX_PKT_BURST], packet_len = 0;
+	uint32_t head_idx, packet_success = 0;
+	uint32_t retry = 0;
+	uint16_t avail_idx, res_cur_idx;
+	uint16_t res_base_idx, res_end_idx;
+	uint16_t free_entries;
+	uint8_t success = 0;
+
+	LOG_DEBUG(VHOST_DATA, "(%"PRIu64") virtio_dev_rx()\n", dev->device_fh);
+	vq = dev->virtqueue[VIRTIO_RXQ];
+	count = (count > MAX_PKT_BURST) ? MAX_PKT_BURST : count;
+
+	/* As many data cores may want access to available buffers, they need to be reserved. */
+	do {
+		res_base_idx = vq->last_used_idx_res;
+		avail_idx = *((volatile uint16_t *)&vq->avail->idx);
+
+		free_entries = (avail_idx - res_base_idx);
+		/* If retry is enabled and the queue is full then we wait and retry to avoid packet loss. */
+		if (enable_retry && unlikely(count > free_entries)) {
+			for (retry = 0; retry < burst_rx_retry_num; retry++) {
+				rte_delay_us(burst_rx_delay_time);
+				avail_idx =
+					*((volatile uint16_t *)&vq->avail->idx);
+				free_entries = (avail_idx - res_base_idx);
+				if (count <= free_entries)
+					break;
+			}
+		}
+
+		/*check that we have enough buffers*/
+		if (unlikely(count > free_entries))
+			count = free_entries;
+
+		if (count == 0)
+			return 0;
+
+		res_end_idx = res_base_idx + count;
+		/* vq->last_used_idx_res is atomically updated. */
+		success = rte_atomic16_cmpset(&vq->last_used_idx_res, res_base_idx,
+									res_end_idx);
+	} while (unlikely(success == 0));
+	res_cur_idx = res_base_idx;
+	LOG_DEBUG(VHOST_DATA, "(%"PRIu64") Current Index %d| End Index %d\n", dev->device_fh, res_cur_idx, res_end_idx);
+
+	/* Prefetch available ring to retrieve indexes. */
+	rte_prefetch0(&vq->avail->ring[res_cur_idx & (vq->size - 1)]);
+
+	/* Retrieve all of the head indexes first to avoid caching issues. */
+	for (head_idx = 0; head_idx < count; head_idx++)
+		head[head_idx] = vq->avail->ring[(res_cur_idx + head_idx) & (vq->size - 1)];
+
+	/*Prefetch descriptor index. */
+	rte_prefetch0(&vq->desc[head[packet_success]]);
+
+	while (res_cur_idx != res_end_idx) {
+		/* Get descriptor from available ring */
+		desc = &vq->desc[head[packet_success]];
+
+		buff = pkts[packet_success];
+
+		/* Convert from gpa to vva (guest physical addr -> vhost virtual addr) */
+		buff_addr = gpa_to_vva(dev, desc->addr);
+		/* Prefetch buffer address. */
+		rte_prefetch0((void*)(uintptr_t)buff_addr);
+
+		/* Copy virtio_hdr to packet and increment buffer address */
+		buff_hdr_addr = buff_addr;
+		packet_len = rte_pktmbuf_data_len(buff) + vq->vhost_hlen;
+
+		/*
+		 * If the descriptors are chained the header and data are
+		 * placed in separate buffers.
+		 */
+		if (desc->flags & VRING_DESC_F_NEXT) {
+			desc->len = vq->vhost_hlen;
+			desc = &vq->desc[desc->next];
+			/* Buffer address translation. */
+			buff_addr = gpa_to_vva(dev, desc->addr);
+			desc->len = rte_pktmbuf_data_len(buff);
+		} else {
+			buff_addr += vq->vhost_hlen;
+			desc->len = packet_len;
+		}
+
+		/* Update used ring with desc information */
+		vq->used->ring[res_cur_idx & (vq->size - 1)].id = head[packet_success];
+		vq->used->ring[res_cur_idx & (vq->size - 1)].len = packet_len;
+
+		/* Copy mbuf data to buffer */
+		rte_memcpy((void *)(uintptr_t)buff_addr,
+			rte_pktmbuf_mtod(buff, const void *),
+			rte_pktmbuf_data_len(buff));
+		PRINT_PACKET(dev, (uintptr_t)buff_addr,
+			rte_pktmbuf_data_len(buff), 0);
+
+		res_cur_idx++;
+		packet_success++;
+
+		rte_memcpy((void *)(uintptr_t)buff_hdr_addr,
+			(const void *)&virtio_hdr, vq->vhost_hlen);
+
+		PRINT_PACKET(dev, (uintptr_t)buff_hdr_addr, vq->vhost_hlen, 1);
+
+		if (res_cur_idx < res_end_idx) {
+			/* Prefetch descriptor index. */
+			rte_prefetch0(&vq->desc[head[packet_success]]);
+		}
+	}
+
+	rte_compiler_barrier();
+
+	/* Wait until it's our turn to add our buffer to the used ring. */
+	while (unlikely(vq->last_used_idx != res_base_idx))
+		rte_pause();
+
+	*(volatile uint16_t *)&vq->used->idx += count;
+	vq->last_used_idx = res_end_idx;
+
+	/* Kick the guest if necessary. */
+	if (!(vq->avail->flags & VRING_AVAIL_F_NO_INTERRUPT))
+		eventfd_write((int)vq->kickfd, 1);
+	return count;
+}
+
+static inline uint32_t __attribute__((always_inline))
+copy_from_mbuf_to_vring(struct virtio_net *dev,
+	uint16_t res_base_idx, uint16_t res_end_idx,
+	struct rte_mbuf *pkt)
+{
+	uint32_t vec_idx = 0;
+	uint32_t entry_success = 0;
+	struct vhost_virtqueue *vq;
+	/* The virtio_hdr is initialised to 0. */
+	struct virtio_net_hdr_mrg_rxbuf virtio_hdr = {
+		{0, 0, 0, 0, 0, 0}, 0};
+	uint16_t cur_idx = res_base_idx;
+	uint64_t vb_addr = 0;
+	uint64_t vb_hdr_addr = 0;
+	uint32_t seg_offset = 0;
+	uint32_t vb_offset = 0;
+	uint32_t seg_avail;
+	uint32_t vb_avail;
+	uint32_t cpy_len, entry_len;
+
+	if (pkt == NULL)
+		return 0;
+
+	LOG_DEBUG(VHOST_DATA, "(%"PRIu64") Current Index %d| "
+		"End Index %d\n",
+		dev->device_fh, cur_idx, res_end_idx);
+
+	/*
+	 * Convert from gpa to vva
+	 * (guest physical addr -> vhost virtual addr)
+	 */
+	vq = dev->virtqueue[VIRTIO_RXQ];
+	vb_addr =
+		gpa_to_vva(dev, vq->buf_vec[vec_idx].buf_addr);
+	vb_hdr_addr = vb_addr;
+
+	/* Prefetch buffer address. */
+	rte_prefetch0((void *)(uintptr_t)vb_addr);
+
+	virtio_hdr.num_buffers = res_end_idx - res_base_idx;
+
+	LOG_DEBUG(VHOST_DATA, "(%"PRIu64") RX: Num merge buffers %d\n",
+		dev->device_fh, virtio_hdr.num_buffers);
+
+	rte_memcpy((void *)(uintptr_t)vb_hdr_addr,
+		(const void *)&virtio_hdr, vq->vhost_hlen);
+
+	PRINT_PACKET(dev, (uintptr_t)vb_hdr_addr, vq->vhost_hlen, 1);
+
+	seg_avail = rte_pktmbuf_data_len(pkt);
+	vb_offset = vq->vhost_hlen;
+	vb_avail =
+		vq->buf_vec[vec_idx].buf_len - vq->vhost_hlen;
+
+	entry_len = vq->vhost_hlen;
+
+	if (vb_avail == 0) {
+		uint32_t desc_idx =
+			vq->buf_vec[vec_idx].desc_idx;
+		vq->desc[desc_idx].len = vq->vhost_hlen;
+
+		if ((vq->desc[desc_idx].flags
+			& VRING_DESC_F_NEXT) == 0) {
+			/* Update used ring with desc information */
+			vq->used->ring[cur_idx & (vq->size - 1)].id
+				= vq->buf_vec[vec_idx].desc_idx;
+			vq->used->ring[cur_idx & (vq->size - 1)].len
+				= entry_len;
+
+			entry_len = 0;
+			cur_idx++;
+			entry_success++;
+		}
+
+		vec_idx++;
+		vb_addr =
+			gpa_to_vva(dev, vq->buf_vec[vec_idx].buf_addr);
+
+		/* Prefetch buffer address. */
+		rte_prefetch0((void *)(uintptr_t)vb_addr);
+		vb_offset = 0;
+		vb_avail = vq->buf_vec[vec_idx].buf_len;
+	}
+
+	cpy_len = RTE_MIN(vb_avail, seg_avail);
+
+	while (cpy_len > 0) {
+		/* Copy mbuf data to vring buffer */
+		rte_memcpy((void *)(uintptr_t)(vb_addr + vb_offset),
+			(const void *)(rte_pktmbuf_mtod(pkt, char*) + seg_offset),
+			cpy_len);
+
+		PRINT_PACKET(dev,
+			(uintptr_t)(vb_addr + vb_offset),
+			cpy_len, 0);
+
+		seg_offset += cpy_len;
+		vb_offset += cpy_len;
+		seg_avail -= cpy_len;
+		vb_avail -= cpy_len;
+		entry_len += cpy_len;
+
+		if (seg_avail != 0) {
+			/*
+			 * The virtio buffer in this vring
+			 * entry reach to its end.
+			 * But the segment doesn't complete.
+			 */
+			if ((vq->desc[vq->buf_vec[vec_idx].desc_idx].flags &
+				VRING_DESC_F_NEXT) == 0) {
+				/* Update used ring with desc information */
+				vq->used->ring[cur_idx & (vq->size - 1)].id
+					= vq->buf_vec[vec_idx].desc_idx;
+				vq->used->ring[cur_idx & (vq->size - 1)].len
+					= entry_len;
+				entry_len = 0;
+				cur_idx++;
+				entry_success++;
+			}
+
+			vec_idx++;
+			vb_addr = gpa_to_vva(dev,
+				vq->buf_vec[vec_idx].buf_addr);
+			vb_offset = 0;
+			vb_avail = vq->buf_vec[vec_idx].buf_len;
+			cpy_len = RTE_MIN(vb_avail, seg_avail);
+		} else {
+			/*
+			 * This current segment complete, need continue to
+			 * check if the whole packet complete or not.
+			 */
+			pkt = pkt->next;
+			if (pkt != NULL) {
+				/*
+				 * There are more segments.
+				 */
+				if (vb_avail == 0) {
+					/*
+					 * This current buffer from vring is
+					 * used up, need fetch next buffer
+					 * from buf_vec.
+					 */
+					uint32_t desc_idx =
+						vq->buf_vec[vec_idx].desc_idx;
+					vq->desc[desc_idx].len = vb_offset;
+
+					if ((vq->desc[desc_idx].flags &
+						VRING_DESC_F_NEXT) == 0) {
+						uint16_t wrapped_idx =
+							cur_idx & (vq->size - 1);
+						/*
+						 * Update used ring with the
+						 * descriptor information
+						 */
+						vq->used->ring[wrapped_idx].id
+							= desc_idx;
+						vq->used->ring[wrapped_idx].len
+							= entry_len;
+						entry_success++;
+						entry_len = 0;
+						cur_idx++;
+					}
+
+					/* Get next buffer from buf_vec. */
+					vec_idx++;
+					vb_addr = gpa_to_vva(dev,
+						vq->buf_vec[vec_idx].buf_addr);
+					vb_avail =
+						vq->buf_vec[vec_idx].buf_len;
+					vb_offset = 0;
+				}
+
+				seg_offset = 0;
+				seg_avail = rte_pktmbuf_data_len(pkt);
+				cpy_len = RTE_MIN(vb_avail, seg_avail);
+			} else {
+				/*
+				 * This whole packet completes.
+				 */
+				uint32_t desc_idx =
+					vq->buf_vec[vec_idx].desc_idx;
+				vq->desc[desc_idx].len = vb_offset;
+
+				while (vq->desc[desc_idx].flags &
+					VRING_DESC_F_NEXT) {
+					desc_idx = vq->desc[desc_idx].next;
+					 vq->desc[desc_idx].len = 0;
+				}
+
+				/* Update used ring with desc information */
+				vq->used->ring[cur_idx & (vq->size - 1)].id
+					= vq->buf_vec[vec_idx].desc_idx;
+				vq->used->ring[cur_idx & (vq->size - 1)].len
+					= entry_len;
+				entry_len = 0;
+				cur_idx++;
+				entry_success++;
+				seg_avail = 0;
+				cpy_len = RTE_MIN(vb_avail, seg_avail);
+			}
+		}
+	}
+
+	return entry_success;
+}
+
+/*
+ * This function adds buffers to the virtio devices RX virtqueue. Buffers can
+ * be received from the physical port or from another virtio device. A packet
+ * count is returned to indicate the number of packets that were succesfully
+ * added to the RX queue. This function works for mergeable RX.
+ */
+static inline uint32_t __attribute__((always_inline))
+virtio_dev_merge_rx(struct virtio_net *dev, struct rte_mbuf **pkts,
+	uint32_t count)
+{
+	struct vhost_virtqueue *vq;
+	uint32_t pkt_idx = 0, entry_success = 0;
+	uint32_t retry = 0;
+	uint16_t avail_idx, res_cur_idx;
+	uint16_t res_base_idx, res_end_idx;
+	uint8_t success = 0;
+
+	LOG_DEBUG(VHOST_DATA, "(%"PRIu64") virtio_dev_merge_rx()\n",
+		dev->device_fh);
+	vq = dev->virtqueue[VIRTIO_RXQ];
+	count = RTE_MIN((uint32_t)MAX_PKT_BURST, count);
+
+	if (count == 0)
+		return 0;
+
+	for (pkt_idx = 0; pkt_idx < count; pkt_idx++) {
+		uint32_t secure_len = 0;
+		uint16_t need_cnt;
+		uint32_t vec_idx = 0;
+		uint32_t pkt_len = pkts[pkt_idx]->pkt_len + vq->vhost_hlen;
+		uint16_t i, id;
+
+		do {
+			/*
+			 * As many data cores may want access to available
+			 * buffers, they need to be reserved.
+			 */
+			res_base_idx = vq->last_used_idx_res;
+			res_cur_idx = res_base_idx;
+
+			do {
+				avail_idx = *((volatile uint16_t *)&vq->avail->idx);
+				if (unlikely(res_cur_idx == avail_idx)) {
+					/*
+					 * If retry is enabled and the queue is
+					 * full then we wait and retry to avoid
+					 * packet loss.
+					 */
+					if (enable_retry) {
+						uint8_t cont = 0;
+						for (retry = 0; retry < burst_rx_retry_num; retry++) {
+							rte_delay_us(burst_rx_delay_time);
+							avail_idx =
+								*((volatile uint16_t *)&vq->avail->idx);
+							if (likely(res_cur_idx != avail_idx)) {
+								cont = 1;
+								break;
+							}
+						}
+						if (cont == 1)
+							continue;
+					}
+
+					LOG_DEBUG(VHOST_DATA,
+						"(%"PRIu64") Failed "
+						"to get enough desc from "
+						"vring\n",
+						dev->device_fh);
+					return pkt_idx;
+				} else {
+					uint16_t wrapped_idx =
+						(res_cur_idx) & (vq->size - 1);
+					uint32_t idx =
+						vq->avail->ring[wrapped_idx];
+					uint8_t next_desc;
+
+					do {
+						next_desc = 0;
+						secure_len += vq->desc[idx].len;
+						if (vq->desc[idx].flags &
+							VRING_DESC_F_NEXT) {
+							idx = vq->desc[idx].next;
+							next_desc = 1;
+						}
+					} while (next_desc);
+
+					res_cur_idx++;
+				}
+			} while (pkt_len > secure_len);
+
+			/* vq->last_used_idx_res is atomically updated. */
+			success = rte_atomic16_cmpset(&vq->last_used_idx_res,
+							res_base_idx,
+							res_cur_idx);
+		} while (success == 0);
+
+		id = res_base_idx;
+		need_cnt = res_cur_idx - res_base_idx;
+
+		for (i = 0; i < need_cnt; i++, id++) {
+			uint16_t wrapped_idx = id & (vq->size - 1);
+			uint32_t idx = vq->avail->ring[wrapped_idx];
+			uint8_t next_desc;
+			do {
+				next_desc = 0;
+				vq->buf_vec[vec_idx].buf_addr =
+					vq->desc[idx].addr;
+				vq->buf_vec[vec_idx].buf_len =
+					vq->desc[idx].len;
+				vq->buf_vec[vec_idx].desc_idx = idx;
+				vec_idx++;
+
+				if (vq->desc[idx].flags & VRING_DESC_F_NEXT) {
+					idx = vq->desc[idx].next;
+					next_desc = 1;
+				}
+			} while (next_desc);
+		}
+
+		res_end_idx = res_cur_idx;
+
+		entry_success = copy_from_mbuf_to_vring(dev, res_base_idx,
+			res_end_idx, pkts[pkt_idx]);
+
+		rte_compiler_barrier();
+
+		/*
+		 * Wait until it's our turn to add our buffer
+		 * to the used ring.
+		 */
+		while (unlikely(vq->last_used_idx != res_base_idx))
+			rte_pause();
+
+		*(volatile uint16_t *)&vq->used->idx += entry_success;
+		vq->last_used_idx = res_end_idx;
+
+		/* Kick the guest if necessary. */
+		if (!(vq->avail->flags & VRING_AVAIL_F_NO_INTERRUPT))
+			eventfd_write((int)vq->kickfd, 1);
+	}
+
+	return count;
+}
+
+/*
+ * Compares a packet destination MAC address to a device MAC address.
+ */
+static inline int __attribute__((always_inline))
+ether_addr_cmp(struct ether_addr *ea, struct ether_addr *eb)
+{
+	return (((*(uint64_t *)ea ^ *(uint64_t *)eb) & MAC_ADDR_CMP) == 0);
+}
+
+/*
+ * This function learns the MAC address of the device and registers this along with a
+ * vlan tag to a VMDQ.
+ */
+static int
+link_vmdq(struct virtio_net *dev, struct rte_mbuf *m)
+{
+	struct ether_hdr *pkt_hdr;
+	struct virtio_net_data_ll *dev_ll;
+	int i, ret;
+
+	/* Learn MAC address of guest device from packet */
+	pkt_hdr = rte_pktmbuf_mtod(m, struct ether_hdr *);
+
+	dev_ll = ll_root_used;
+
+	while (dev_ll != NULL) {
+		if (ether_addr_cmp(&(pkt_hdr->s_addr), &dev_ll->dev->mac_address)) {
+			RTE_LOG(INFO, VHOST_DATA, "(%"PRIu64") WARNING: This device is using an existing MAC address and has not been registered.\n", dev->device_fh);
+			return -1;
+		}
+		dev_ll = dev_ll->next;
+	}
+
+	for (i = 0; i < ETHER_ADDR_LEN; i++)
+		dev->mac_address.addr_bytes[i] = pkt_hdr->s_addr.addr_bytes[i];
+
+	/* vlan_tag currently uses the device_id. */
+	dev->vlan_tag = vlan_tags[dev->device_fh];
+
+	/* Print out VMDQ registration info. */
+	RTE_LOG(INFO, VHOST_DATA, "(%"PRIu64") MAC_ADDRESS %02x:%02x:%02x:%02x:%02x:%02x and VLAN_TAG %d registered\n",
+		dev->device_fh,
+		dev->mac_address.addr_bytes[0], dev->mac_address.addr_bytes[1],
+		dev->mac_address.addr_bytes[2], dev->mac_address.addr_bytes[3],
+		dev->mac_address.addr_bytes[4], dev->mac_address.addr_bytes[5],
+		dev->vlan_tag);
+
+	/* Register the MAC address. */
+	ret = rte_eth_dev_mac_addr_add(ports[0], &dev->mac_address, (uint32_t)dev->device_fh);
+	if (ret)
+		RTE_LOG(ERR, VHOST_DATA, "(%"PRIu64") Failed to add device MAC address to VMDQ\n",
+					dev->device_fh);
+
+	/* Enable stripping of the vlan tag as we handle routing. */
+	rte_eth_dev_set_vlan_strip_on_queue(ports[0], (uint16_t)dev->vmdq_rx_q, 1);
+
+	/* Set device as ready for RX. */
+	dev->ready = DEVICE_RX;
+
+	return 0;
+}
+
+/*
+ * Removes MAC address and vlan tag from VMDQ. Ensures that nothing is adding buffers to the RX
+ * queue before disabling RX on the device.
+ */
+static inline void
+unlink_vmdq(struct virtio_net *dev)
+{
+	unsigned i = 0;
+	unsigned rx_count;
+	struct rte_mbuf *pkts_burst[MAX_PKT_BURST];
+
+	if (dev->ready == DEVICE_RX) {
+		/*clear MAC and VLAN settings*/
+		rte_eth_dev_mac_addr_remove(ports[0], &dev->mac_address);
+		for (i = 0; i < 6; i++)
+			dev->mac_address.addr_bytes[i] = 0;
+
+		dev->vlan_tag = 0;
+
+		/*Clear out the receive buffers*/
+		rx_count = rte_eth_rx_burst(ports[0],
+					(uint16_t)dev->vmdq_rx_q, pkts_burst, MAX_PKT_BURST);
+
+		while (rx_count) {
+			for (i = 0; i < rx_count; i++)
+				rte_pktmbuf_free(pkts_burst[i]);
+
+			rx_count = rte_eth_rx_burst(ports[0],
+					(uint16_t)dev->vmdq_rx_q, pkts_burst, MAX_PKT_BURST);
+		}
+
+		dev->ready = DEVICE_MAC_LEARNING;
+	}
+}
+
+/*
+ * Check if the packet destination MAC address is for a local device. If so then put
+ * the packet on that devices RX queue. If not then return.
+ */
+static inline unsigned __attribute__((always_inline))
+virtio_tx_local(struct virtio_net *dev, struct rte_mbuf *m)
+{
+	struct virtio_net_data_ll *dev_ll;
+	struct ether_hdr *pkt_hdr;
+	uint64_t ret = 0;
+
+	pkt_hdr = rte_pktmbuf_mtod(m, struct ether_hdr *);
+
+	/*get the used devices list*/
+	dev_ll = ll_root_used;
+
+	while (dev_ll != NULL) {
+		if ((dev_ll->dev->ready == DEVICE_RX) && ether_addr_cmp(&(pkt_hdr->d_addr),
+				          &dev_ll->dev->mac_address)) {
+
+			/* Drop the packet if the TX packet is destined for the TX device. */
+			if (dev_ll->dev->device_fh == dev->device_fh) {
+				LOG_DEBUG(VHOST_DATA, "(%"PRIu64") TX: Source and destination MAC addresses are the same. Dropping packet.\n",
+							dev_ll->dev->device_fh);
+				return 0;
+			}
+
+
+			LOG_DEBUG(VHOST_DATA, "(%"PRIu64") TX: MAC address is local\n", dev_ll->dev->device_fh);
+
+			if (dev_ll->dev->remove) {
+				/*drop the packet if the device is marked for removal*/
+				LOG_DEBUG(VHOST_DATA, "(%"PRIu64") Device is marked for removal\n", dev_ll->dev->device_fh);
+			} else {
+				uint32_t mergeable =
+					dev_ll->dev->features &
+					(1 << VIRTIO_NET_F_MRG_RXBUF);
+
+				/*send the packet to the local virtio device*/
+				if (likely(mergeable == 0))
+					ret = virtio_dev_rx(dev_ll->dev, &m, 1);
+				else
+					ret = virtio_dev_merge_rx(dev_ll->dev,
+						&m, 1);
+
+				if (enable_stats) {
+					rte_atomic64_add(
+					&dev_statistics[dev_ll->dev->device_fh].rx_total_atomic,
+					1);
+					rte_atomic64_add(
+					&dev_statistics[dev_ll->dev->device_fh].rx_atomic,
+					ret);
+					dev_statistics[dev->device_fh].tx_total++;
+					dev_statistics[dev->device_fh].tx += ret;
+				}
+			}
+
+			return 0;
+		}
+		dev_ll = dev_ll->next;
+	}
+
+	return -1;
+}
+
+/*
+ * This function routes the TX packet to the correct interface. This may be a local device
+ * or the physical port.
+ */
+static inline void __attribute__((always_inline))
+virtio_tx_route(struct virtio_net* dev, struct rte_mbuf *m, struct rte_mempool *mbuf_pool, uint16_t vlan_tag)
+{
+	struct mbuf_table *tx_q;
+	struct vlan_ethhdr *vlan_hdr;
+	struct rte_mbuf **m_table;
+	struct rte_mbuf *mbuf, *prev;
+	unsigned len, ret, offset = 0;
+	const uint16_t lcore_id = rte_lcore_id();
+	struct virtio_net_data_ll *dev_ll = ll_root_used;
+	struct ether_hdr *pkt_hdr = rte_pktmbuf_mtod(m, struct ether_hdr *);
+
+	/*check if destination is local VM*/
+	if ((vm2vm_mode == VM2VM_SOFTWARE) && (virtio_tx_local(dev, m) == 0))
+		return;
+
+	if (vm2vm_mode == VM2VM_HARDWARE) {
+		while (dev_ll != NULL) {
+			if ((dev_ll->dev->ready == DEVICE_RX)
+				&& ether_addr_cmp(&(pkt_hdr->d_addr),
+				&dev_ll->dev->mac_address)) {
+				/*
+				 * Drop the packet if the TX packet is
+				 * destined for the TX device.
+				 */
+				if (dev_ll->dev->device_fh == dev->device_fh) {
+					LOG_DEBUG(VHOST_DATA,
+					"(%"PRIu64") TX: Source and destination"
+					" MAC addresses are the same. Dropping "
+					"packet.\n",
+					dev_ll->dev->device_fh);
+					return;
+				}
+				offset = 4;
+				vlan_tag =
+				(uint16_t)
+				vlan_tags[(uint16_t)dev_ll->dev->device_fh];
+
+				LOG_DEBUG(VHOST_DATA,
+				"(%"PRIu64") TX: pkt to local VM device id:"
+				"(%"PRIu64") vlan tag: %d.\n",
+				dev->device_fh, dev_ll->dev->device_fh,
+				vlan_tag);
+
+				break;
+			}
+			dev_ll = dev_ll->next;
+		}
+	}
+
+	LOG_DEBUG(VHOST_DATA, "(%"PRIu64") TX: MAC address is external\n", dev->device_fh);
+
+	/*Add packet to the port tx queue*/
+	tx_q = &lcore_tx_queue[lcore_id];
+	len = tx_q->len;
+
+	/* Allocate an mbuf and populate the structure. */
+	mbuf = rte_pktmbuf_alloc(mbuf_pool);
+	if (unlikely(mbuf == NULL)) {
+		RTE_LOG(ERR, VHOST_DATA,
+			"Failed to allocate memory for mbuf.\n");
+		return;
+	}
+
+	mbuf->data_len = m->data_len + VLAN_HLEN + offset;
+	mbuf->pkt_len = m->pkt_len + VLAN_HLEN + offset;
+	mbuf->nb_segs = m->nb_segs;
+
+	/* Copy ethernet header to mbuf. */
+	rte_memcpy(rte_pktmbuf_mtod(mbuf, void *),
+		rte_pktmbuf_mtod(m, const void *),
+		ETH_HLEN);
+
+
+	/* Setup vlan header. Bytes need to be re-ordered for network with htons()*/
+	vlan_hdr = rte_pktmbuf_mtod(mbuf, struct vlan_ethhdr *);
+	vlan_hdr->h_vlan_encapsulated_proto = vlan_hdr->h_vlan_proto;
+	vlan_hdr->h_vlan_proto = htons(ETH_P_8021Q);
+	vlan_hdr->h_vlan_TCI = htons(vlan_tag);
+
+	/* Copy the remaining packet contents to the mbuf. */
+	rte_memcpy((void *)(rte_pktmbuf_mtod(mbuf, uint8_t *) + VLAN_ETH_HLEN),
+		(const void *)(rte_pktmbuf_mtod(m, uint8_t *) + ETH_HLEN),
+		(m->data_len - ETH_HLEN));
+
+	/* Copy the remaining segments for the whole packet. */
+	prev = mbuf;
+	while (m->next) {
+		/* Allocate an mbuf and populate the structure. */
+		struct rte_mbuf *next_mbuf = rte_pktmbuf_alloc(mbuf_pool);
+		if (unlikely(next_mbuf == NULL)) {
+			rte_pktmbuf_free(mbuf);
+			RTE_LOG(ERR, VHOST_DATA,
+				"Failed to allocate memory for mbuf.\n");
+			return;
+		}
+
+		m = m->next;
+		prev->next = next_mbuf;
+		prev = next_mbuf;
+		next_mbuf->data_len = m->data_len;
+
+		/* Copy data to next mbuf. */
+		rte_memcpy(rte_pktmbuf_mtod(next_mbuf, void *),
+			rte_pktmbuf_mtod(m, const void *), m->data_len);
+	}
+
+	tx_q->m_table[len] = mbuf;
+	len++;
+	if (enable_stats) {
+		dev_statistics[dev->device_fh].tx_total++;
+		dev_statistics[dev->device_fh].tx++;
+	}
+
+	if (unlikely(len == MAX_PKT_BURST)) {
+		m_table = (struct rte_mbuf **)tx_q->m_table;
+		ret = rte_eth_tx_burst(ports[0], (uint16_t)tx_q->txq_id, m_table, (uint16_t) len);
+		/* Free any buffers not handled by TX and update the port stats. */
+		if (unlikely(ret < len)) {
+			do {
+				rte_pktmbuf_free(m_table[ret]);
+			} while (++ret < len);
+		}
+
+		len = 0;
+	}
+
+	tx_q->len = len;
+	return;
+}
+
+static inline void __attribute__((always_inline))
+virtio_dev_tx(struct virtio_net* dev, struct rte_mempool *mbuf_pool)
+{
+	struct rte_mbuf m;
+	struct vhost_virtqueue *vq;
+	struct vring_desc *desc;
+	uint64_t buff_addr = 0;
+	uint32_t head[MAX_PKT_BURST];
+	uint32_t used_idx;
+	uint32_t i;
+	uint16_t free_entries, packet_success = 0;
+	uint16_t avail_idx;
+
+	vq = dev->virtqueue[VIRTIO_TXQ];
+	avail_idx =  *((volatile uint16_t *)&vq->avail->idx);
+
+	/* If there are no available buffers then return. */
+	if (vq->last_used_idx == avail_idx)
+		return;
+
+	LOG_DEBUG(VHOST_DATA, "(%"PRIu64") virtio_dev_tx()\n", dev->device_fh);
+
+	/* Prefetch available ring to retrieve head indexes. */
+	rte_prefetch0(&vq->avail->ring[vq->last_used_idx & (vq->size - 1)]);
+
+	/*get the number of free entries in the ring*/
+	free_entries = (avail_idx - vq->last_used_idx);
+
+	/* Limit to MAX_PKT_BURST. */
+	if (free_entries > MAX_PKT_BURST)
+		free_entries = MAX_PKT_BURST;
+
+	LOG_DEBUG(VHOST_DATA, "(%"PRIu64") Buffers available %d\n", dev->device_fh, free_entries);
+	/* Retrieve all of the head indexes first to avoid caching issues. */
+	for (i = 0; i < free_entries; i++)
+		head[i] = vq->avail->ring[(vq->last_used_idx + i) & (vq->size - 1)];
+
+	/* Prefetch descriptor index. */
+	rte_prefetch0(&vq->desc[head[packet_success]]);
+	rte_prefetch0(&vq->used->ring[vq->last_used_idx & (vq->size - 1)]);
+
+	while (packet_success < free_entries) {
+		desc = &vq->desc[head[packet_success]];
+
+		/* Discard first buffer as it is the virtio header */
+		desc = &vq->desc[desc->next];
+
+		/* Buffer address translation. */
+		buff_addr = gpa_to_vva(dev, desc->addr);
+		/* Prefetch buffer address. */
+		rte_prefetch0((void*)(uintptr_t)buff_addr);
+
+		used_idx = vq->last_used_idx & (vq->size - 1);
+
+		if (packet_success < (free_entries - 1)) {
+			/* Prefetch descriptor index. */
+			rte_prefetch0(&vq->desc[head[packet_success+1]]);
+			rte_prefetch0(&vq->used->ring[(used_idx + 1) & (vq->size - 1)]);
+		}
+
+		/* Update used index buffer information. */
+		vq->used->ring[used_idx].id = head[packet_success];
+		vq->used->ring[used_idx].len = 0;
+
+		/* Setup dummy mbuf. This is copied to a real mbuf if transmitted out the physical port. */
+		m.data_len = desc->len;
+		m.pkt_len = desc->len;
+		m.data_off = 0;
+
+		PRINT_PACKET(dev, (uintptr_t)buff_addr, desc->len, 0);
+
+		/* If this is the first received packet we need to learn the MAC and setup VMDQ */
+		if (dev->ready == DEVICE_MAC_LEARNING) {
+			if (dev->remove || (link_vmdq(dev, &m) == -1)) {
+				/*discard frame if device is scheduled for removal or a duplicate MAC address is found. */
+				packet_success += free_entries;
+				vq->last_used_idx += packet_success;
+				break;
+			}
+		}
+		virtio_tx_route(dev, &m, mbuf_pool, (uint16_t)dev->device_fh);
+
+		vq->last_used_idx++;
+		packet_success++;
+	}
+
+	rte_compiler_barrier();
+	vq->used->idx += packet_success;
+	/* Kick guest if required. */
+	if (!(vq->avail->flags & VRING_AVAIL_F_NO_INTERRUPT))
+		eventfd_write((int)vq->kickfd, 1);
+}
+
+/* This function works for TX packets with mergeable feature enabled. */
+static inline void __attribute__((always_inline))
+virtio_dev_merge_tx(struct virtio_net *dev, struct rte_mempool *mbuf_pool)
+{
+	struct rte_mbuf *m, *prev;
+	struct vhost_virtqueue *vq;
+	struct vring_desc *desc;
+	uint64_t vb_addr = 0;
+	uint32_t head[MAX_PKT_BURST];
+	uint32_t used_idx;
+	uint32_t i;
+	uint16_t free_entries, entry_success = 0;
+	uint16_t avail_idx;
+	uint32_t buf_size = MBUF_SIZE - (sizeof(struct rte_mbuf)
+			+ RTE_PKTMBUF_HEADROOM);
+
+	vq = dev->virtqueue[VIRTIO_TXQ];
+	avail_idx =  *((volatile uint16_t *)&vq->avail->idx);
+
+	/* If there are no available buffers then return. */
+	if (vq->last_used_idx == avail_idx)
+		return;
+
+	LOG_DEBUG(VHOST_DATA, "(%"PRIu64") virtio_dev_merge_tx()\n",
+		dev->device_fh);
+
+	/* Prefetch available ring to retrieve head indexes. */
+	rte_prefetch0(&vq->avail->ring[vq->last_used_idx & (vq->size - 1)]);
+
+	/*get the number of free entries in the ring*/
+	free_entries = (avail_idx - vq->last_used_idx);
+
+	/* Limit to MAX_PKT_BURST. */
+	free_entries = RTE_MIN(free_entries, MAX_PKT_BURST);
+
+	LOG_DEBUG(VHOST_DATA, "(%"PRIu64") Buffers available %d\n",
+		dev->device_fh, free_entries);
+	/* Retrieve all of the head indexes first to avoid caching issues. */
+	for (i = 0; i < free_entries; i++)
+		head[i] = vq->avail->ring[(vq->last_used_idx + i) & (vq->size - 1)];
+
+	/* Prefetch descriptor index. */
+	rte_prefetch0(&vq->desc[head[entry_success]]);
+	rte_prefetch0(&vq->used->ring[vq->last_used_idx & (vq->size - 1)]);
+
+	while (entry_success < free_entries) {
+		uint32_t vb_avail, vb_offset;
+		uint32_t seg_avail, seg_offset;
+		uint32_t cpy_len;
+		uint32_t seg_num = 0;
+		struct rte_mbuf *cur;
+		uint8_t alloc_err = 0;
+
+		desc = &vq->desc[head[entry_success]];
+
+		/* Discard first buffer as it is the virtio header */
+		desc = &vq->desc[desc->next];
+
+		/* Buffer address translation. */
+		vb_addr = gpa_to_vva(dev, desc->addr);
+		/* Prefetch buffer address. */
+		rte_prefetch0((void *)(uintptr_t)vb_addr);
+
+		used_idx = vq->last_used_idx & (vq->size - 1);
+
+		if (entry_success < (free_entries - 1)) {
+			/* Prefetch descriptor index. */
+			rte_prefetch0(&vq->desc[head[entry_success+1]]);
+			rte_prefetch0(&vq->used->ring[(used_idx + 1) & (vq->size - 1)]);
+		}
+
+		/* Update used index buffer information. */
+		vq->used->ring[used_idx].id = head[entry_success];
+		vq->used->ring[used_idx].len = 0;
+
+		vb_offset = 0;
+		vb_avail = desc->len;
+		seg_offset = 0;
+		seg_avail = buf_size;
+		cpy_len = RTE_MIN(vb_avail, seg_avail);
+
+		PRINT_PACKET(dev, (uintptr_t)vb_addr, desc->len, 0);
+
+		/* Allocate an mbuf and populate the structure. */
+		m = rte_pktmbuf_alloc(mbuf_pool);
+		if (unlikely(m == NULL)) {
+			RTE_LOG(ERR, VHOST_DATA,
+				"Failed to allocate memory for mbuf.\n");
+			return;
+		}
+
+		seg_num++;
+		cur = m;
+		prev = m;
+		while (cpy_len != 0) {
+			rte_memcpy((void *)(rte_pktmbuf_mtod(cur, char *) + seg_offset),
+				(void *)((uintptr_t)(vb_addr + vb_offset)),
+				cpy_len);
+
+			seg_offset += cpy_len;
+			vb_offset += cpy_len;
+			vb_avail -= cpy_len;
+			seg_avail -= cpy_len;
+
+			if (vb_avail != 0) {
+				/*
+				 * The segment reachs to its end,
+				 * while the virtio buffer in TX vring has
+				 * more data to be copied.
+				 */
+				cur->data_len = seg_offset;
+				m->pkt_len += seg_offset;
+				/* Allocate mbuf and populate the structure. */
+				cur = rte_pktmbuf_alloc(mbuf_pool);
+				if (unlikely(cur == NULL)) {
+					RTE_LOG(ERR, VHOST_DATA, "Failed to "
+						"allocate memory for mbuf.\n");
+					rte_pktmbuf_free(m);
+					alloc_err = 1;
+					break;
+				}
+
+				seg_num++;
+				prev->next = cur;
+				prev = cur;
+				seg_offset = 0;
+				seg_avail = buf_size;
+			} else {
+				if (desc->flags & VRING_DESC_F_NEXT) {
+					/*
+					 * There are more virtio buffers in
+					 * same vring entry need to be copied.
+					 */
+					if (seg_avail == 0) {
+						/*
+						 * The current segment hasn't
+						 * room to accomodate more
+						 * data.
+						 */
+						cur->data_len = seg_offset;
+						m->pkt_len += seg_offset;
+						/*
+						 * Allocate an mbuf and
+						 * populate the structure.
+						 */
+						cur = rte_pktmbuf_alloc(mbuf_pool);
+						if (unlikely(cur == NULL)) {
+							RTE_LOG(ERR,
+								VHOST_DATA,
+								"Failed to "
+								"allocate memory "
+								"for mbuf\n");
+							rte_pktmbuf_free(m);
+							alloc_err = 1;
+							break;
+						}
+						seg_num++;
+						prev->next = cur;
+						prev = cur;
+						seg_offset = 0;
+						seg_avail = buf_size;
+					}
+
+					desc = &vq->desc[desc->next];
+
+					/* Buffer address translation. */
+					vb_addr = gpa_to_vva(dev, desc->addr);
+					/* Prefetch buffer address. */
+					rte_prefetch0((void *)(uintptr_t)vb_addr);
+					vb_offset = 0;
+					vb_avail = desc->len;
+
+					PRINT_PACKET(dev, (uintptr_t)vb_addr,
+						desc->len, 0);
+				} else {
+					/* The whole packet completes. */
+					cur->data_len = seg_offset;
+					m->pkt_len += seg_offset;
+					vb_avail = 0;
+				}
+			}
+
+			cpy_len = RTE_MIN(vb_avail, seg_avail);
+		}
+
+		if (unlikely(alloc_err == 1))
+			break;
+
+		m->nb_segs = seg_num;
+
+		/*
+		 * If this is the first received packet we need to learn
+		 * the MAC and setup VMDQ
+		 */
+		if (dev->ready == DEVICE_MAC_LEARNING) {
+			if (dev->remove || (link_vmdq(dev, m) == -1)) {
+				/*
+				 * Discard frame if device is scheduled for
+				 * removal or a duplicate MAC address is found.
+				 */
+				entry_success = free_entries;
+				vq->last_used_idx += entry_success;
+				rte_pktmbuf_free(m);
+				break;
+			}
+		}
+
+		virtio_tx_route(dev, m, mbuf_pool, (uint16_t)dev->device_fh);
+		vq->last_used_idx++;
+		entry_success++;
+		rte_pktmbuf_free(m);
+	}
+
+	rte_compiler_barrier();
+	vq->used->idx += entry_success;
+	/* Kick guest if required. */
+	if (!(vq->avail->flags & VRING_AVAIL_F_NO_INTERRUPT))
+		eventfd_write((int)vq->kickfd, 1);
+
+}
+
+/*
+ * This function is called by each data core. It handles all RX/TX registered with the
+ * core. For TX the specific lcore linked list is used. For RX, MAC addresses are compared
+ * with all devices in the main linked list.
+ */
+static int
+switch_worker(__attribute__((unused)) void *arg)
+{
+	struct rte_mempool *mbuf_pool = arg;
+	struct virtio_net *dev = NULL;
+	struct rte_mbuf *pkts_burst[MAX_PKT_BURST];
+	struct virtio_net_data_ll *dev_ll;
+	struct mbuf_table *tx_q;
+	volatile struct lcore_ll_info *lcore_ll;
+	const uint64_t drain_tsc = (rte_get_tsc_hz() + US_PER_S - 1) / US_PER_S * BURST_TX_DRAIN_US;
+	uint64_t prev_tsc, diff_tsc, cur_tsc, ret_count = 0;
+	unsigned ret, i;
+	const uint16_t lcore_id = rte_lcore_id();
+	const uint16_t num_cores = (uint16_t)rte_lcore_count();
+	uint16_t rx_count = 0;
+	uint32_t mergeable = 0;
+
+	RTE_LOG(INFO, VHOST_DATA, "Procesing on Core %u started\n", lcore_id);
+	lcore_ll = lcore_info[lcore_id].lcore_ll;
+	prev_tsc = 0;
+
+	tx_q = &lcore_tx_queue[lcore_id];
+	for (i = 0; i < num_cores; i ++) {
+		if (lcore_ids[i] == lcore_id) {
+			tx_q->txq_id = i;
+			break;
+		}
+	}
+
+	while(1) {
+		cur_tsc = rte_rdtsc();
+		/*
+		 * TX burst queue drain
+		 */
+		diff_tsc = cur_tsc - prev_tsc;
+		if (unlikely(diff_tsc > drain_tsc)) {
+
+			if (tx_q->len) {
+				LOG_DEBUG(VHOST_DATA, "TX queue drained after timeout with burst size %u \n", tx_q->len);
+
+				/*Tx any packets in the queue*/
+				ret = rte_eth_tx_burst(ports[0], (uint16_t)tx_q->txq_id,
+									   (struct rte_mbuf **)tx_q->m_table,
+									   (uint16_t)tx_q->len);
+				if (unlikely(ret < tx_q->len)) {
+					do {
+						rte_pktmbuf_free(tx_q->m_table[ret]);
+					} while (++ret < tx_q->len);
+				}
+
+				tx_q->len = 0;
+			}
+
+			prev_tsc = cur_tsc;
+
+		}
+
+		rte_prefetch0(lcore_ll->ll_root_used);
+		/*
+		 * Inform the configuration core that we have exited the linked list and that no devices are
+		 * in use if requested.
+		 */
+		if (lcore_ll->dev_removal_flag == REQUEST_DEV_REMOVAL)
+			lcore_ll->dev_removal_flag = ACK_DEV_REMOVAL;
+
+		/*
+		 * Process devices
+		 */
+		dev_ll = lcore_ll->ll_root_used;
+
+		while (dev_ll != NULL) {
+			/*get virtio device ID*/
+			dev = dev_ll->dev;
+			mergeable =
+				dev->features & (1 << VIRTIO_NET_F_MRG_RXBUF);
+
+			if (dev->remove) {
+				dev_ll = dev_ll->next;
+				unlink_vmdq(dev);
+				dev->ready = DEVICE_SAFE_REMOVE;
+				continue;
+			}
+			if (likely(dev->ready == DEVICE_RX)) {
+				/*Handle guest RX*/
+				rx_count = rte_eth_rx_burst(ports[0],
+					(uint16_t)dev->vmdq_rx_q, pkts_burst, MAX_PKT_BURST);
+
+				if (rx_count) {
+					if (likely(mergeable == 0))
+						ret_count =
+							virtio_dev_rx(dev,
+							pkts_burst, rx_count);
+					else
+						ret_count =
+							virtio_dev_merge_rx(dev,
+							pkts_burst, rx_count);
+
+					if (enable_stats) {
+						rte_atomic64_add(
+						&dev_statistics[dev_ll->dev->device_fh].rx_total_atomic,
+						rx_count);
+						rte_atomic64_add(
+						&dev_statistics[dev_ll->dev->device_fh].rx_atomic, ret_count);
+					}
+					while (likely(rx_count)) {
+						rx_count--;
+						rte_pktmbuf_free(pkts_burst[rx_count]);
+					}
+
+				}
+			}
+
+			if (!dev->remove) {
+				/*Handle guest TX*/
+				if (likely(mergeable == 0))
+					virtio_dev_tx(dev, mbuf_pool);
+				else
+					virtio_dev_merge_tx(dev, mbuf_pool);
+			}
+
+			/*move to the next device in the list*/
+			dev_ll = dev_ll->next;
+		}
+	}
+
+	return 0;
+}
+
+/*
+ * This function gets available ring number for zero copy rx.
+ * Only one thread will call this funciton for a paticular virtio device,
+ * so, it is designed as non-thread-safe function.
+ */
+static inline uint32_t __attribute__((always_inline))
+get_available_ring_num_zcp(struct virtio_net *dev)
+{
+	struct vhost_virtqueue *vq = dev->virtqueue[VIRTIO_RXQ];
+	uint16_t avail_idx;
+
+	avail_idx = *((volatile uint16_t *)&vq->avail->idx);
+	return (uint32_t)(avail_idx - vq->last_used_idx_res);
+}
+
+/*
+ * This function gets available ring index for zero copy rx,
+ * it will retry 'burst_rx_retry_num' times till it get enough ring index.
+ * Only one thread will call this funciton for a paticular virtio device,
+ * so, it is designed as non-thread-safe function.
+ */
+static inline uint32_t __attribute__((always_inline))
+get_available_ring_index_zcp(struct virtio_net *dev,
+	uint16_t *res_base_idx, uint32_t count)
+{
+	struct vhost_virtqueue *vq = dev->virtqueue[VIRTIO_RXQ];
+	uint16_t avail_idx;
+	uint32_t retry = 0;
+	uint16_t free_entries;
+
+	*res_base_idx = vq->last_used_idx_res;
+	avail_idx = *((volatile uint16_t *)&vq->avail->idx);
+	free_entries = (avail_idx - *res_base_idx);
+
+	LOG_DEBUG(VHOST_DATA, "(%"PRIu64") in get_available_ring_index_zcp: "
+			"avail idx: %d, "
+			"res base idx:%d, free entries:%d\n",
+			dev->device_fh, avail_idx, *res_base_idx,
+			free_entries);
+
+	/*
+	 * If retry is enabled and the queue is full then we wait
+	 * and retry to avoid packet loss.
+	 */
+	if (enable_retry && unlikely(count > free_entries)) {
+		for (retry = 0; retry < burst_rx_retry_num; retry++) {
+			rte_delay_us(burst_rx_delay_time);
+			avail_idx = *((volatile uint16_t *)&vq->avail->idx);
+			free_entries = (avail_idx - *res_base_idx);
+			if (count <= free_entries)
+				break;
+		}
+	}
+
+	/*check that we have enough buffers*/
+	if (unlikely(count > free_entries))
+		count = free_entries;
+
+	if (unlikely(count == 0)) {
+		LOG_DEBUG(VHOST_DATA,
+			"(%"PRIu64") Fail in get_available_ring_index_zcp: "
+			"avail idx: %d, res base idx:%d, free entries:%d\n",
+			dev->device_fh, avail_idx,
+			*res_base_idx, free_entries);
+		return 0;
+	}
+
+	vq->last_used_idx_res = *res_base_idx + count;
+
+	return count;
+}
+
+/*
+ * This function put descriptor back to used list.
+ */
+static inline void __attribute__((always_inline))
+put_desc_to_used_list_zcp(struct vhost_virtqueue *vq, uint16_t desc_idx)
+{
+	uint16_t res_cur_idx = vq->last_used_idx;
+	vq->used->ring[res_cur_idx & (vq->size - 1)].id = (uint32_t)desc_idx;
+	vq->used->ring[res_cur_idx & (vq->size - 1)].len = 0;
+	rte_compiler_barrier();
+	*(volatile uint16_t *)&vq->used->idx += 1;
+	vq->last_used_idx += 1;
+
+	/* Kick the guest if necessary. */
+	if (!(vq->avail->flags & VRING_AVAIL_F_NO_INTERRUPT))
+		eventfd_write((int)vq->kickfd, 1);
+}
+
+/*
+ * This function get available descriptor from vitio vring and un-attached mbuf
+ * from vpool->ring, and then attach them together. It needs adjust the offset
+ * for buff_addr and phys_addr accroding to PMD implementation, otherwise the
+ * frame data may be put to wrong location in mbuf.
+ */
+static inline void __attribute__((always_inline))
+attach_rxmbuf_zcp(struct virtio_net *dev)
+{
+	uint16_t res_base_idx, desc_idx;
+	uint64_t buff_addr, phys_addr;
+	struct vhost_virtqueue *vq;
+	struct vring_desc *desc;
+	struct rte_mbuf *mbuf = NULL;
+	struct vpool *vpool;
+	hpa_type addr_type;
+
+	vpool = &vpool_array[dev->vmdq_rx_q];
+	vq = dev->virtqueue[VIRTIO_RXQ];
+
+	do {
+		if (unlikely(get_available_ring_index_zcp(dev, &res_base_idx,
+				1) != 1))
+			return;
+		desc_idx = vq->avail->ring[(res_base_idx) & (vq->size - 1)];
+
+		desc = &vq->desc[desc_idx];
+		if (desc->flags & VRING_DESC_F_NEXT) {
+			desc = &vq->desc[desc->next];
+			buff_addr = gpa_to_vva(dev, desc->addr);
+			phys_addr = gpa_to_hpa(dev, desc->addr, desc->len,
+					&addr_type);
+		} else {
+			buff_addr = gpa_to_vva(dev,
+					desc->addr + vq->vhost_hlen);
+			phys_addr = gpa_to_hpa(dev,
+					desc->addr + vq->vhost_hlen,
+					desc->len, &addr_type);
+		}
+
+		if (unlikely(addr_type == PHYS_ADDR_INVALID)) {
+			RTE_LOG(ERR, VHOST_DATA, "(%"PRIu64") Invalid frame buffer"
+				" address found when attaching RX frame buffer"
+				" address!\n", dev->device_fh);
+			put_desc_to_used_list_zcp(vq, desc_idx);
+			continue;
+		}
+
+		/*
+		 * Check if the frame buffer address from guest crosses
+		 * sub-region or not.
+		 */
+		if (unlikely(addr_type == PHYS_ADDR_CROSS_SUBREG)) {
+			RTE_LOG(ERR, VHOST_DATA,
+				"(%"PRIu64") Frame buffer address cross "
+				"sub-regioin found when attaching RX frame "
+				"buffer address!\n",
+				dev->device_fh);
+			put_desc_to_used_list_zcp(vq, desc_idx);
+			continue;
+		}
+	} while (unlikely(phys_addr == 0));
+
+	rte_ring_sc_dequeue(vpool->ring, (void **)&mbuf);
+	if (unlikely(mbuf == NULL)) {
+		LOG_DEBUG(VHOST_DATA,
+			"(%"PRIu64") in attach_rxmbuf_zcp: "
+			"ring_sc_dequeue fail.\n",
+			dev->device_fh);
+		put_desc_to_used_list_zcp(vq, desc_idx);
+		return;
+	}
+
+	if (unlikely(vpool->buf_size > desc->len)) {
+		LOG_DEBUG(VHOST_DATA,
+			"(%"PRIu64") in attach_rxmbuf_zcp: frame buffer "
+			"length(%d) of descriptor idx: %d less than room "
+			"size required: %d\n",
+			dev->device_fh, desc->len, desc_idx, vpool->buf_size);
+		put_desc_to_used_list_zcp(vq, desc_idx);
+		rte_ring_sp_enqueue(vpool->ring, (void *)mbuf);
+		return;
+	}
+
+	mbuf->buf_addr = (void *)(uintptr_t)(buff_addr - RTE_PKTMBUF_HEADROOM);
+	mbuf->data_off = RTE_PKTMBUF_HEADROOM;
+	mbuf->buf_physaddr = phys_addr - RTE_PKTMBUF_HEADROOM;
+	mbuf->data_len = desc->len;
+	MBUF_HEADROOM_UINT32(mbuf) = (uint32_t)desc_idx;
+
+	LOG_DEBUG(VHOST_DATA,
+		"(%"PRIu64") in attach_rxmbuf_zcp: res base idx:%d, "
+		"descriptor idx:%d\n",
+		dev->device_fh, res_base_idx, desc_idx);
+
+	__rte_mbuf_raw_free(mbuf);
+
+	return;
+}
+
+/*
+ * Detach an attched packet mbuf -
+ *  - restore original mbuf address and length values.
+ *  - reset pktmbuf data and data_len to their default values.
+ *  All other fields of the given packet mbuf will be left intact.
+ *
+ * @param m
+ *   The attached packet mbuf.
+ */
+static inline void pktmbuf_detach_zcp(struct rte_mbuf *m)
+{
+	const struct rte_mempool *mp = m->pool;
+	void *buf = RTE_MBUF_TO_BADDR(m);
+	uint32_t buf_ofs;
+	uint32_t buf_len = mp->elt_size - sizeof(*m);
+	m->buf_physaddr = rte_mempool_virt2phy(mp, m) + sizeof(*m);
+
+	m->buf_addr = buf;
+	m->buf_len = (uint16_t)buf_len;
+
+	buf_ofs = (RTE_PKTMBUF_HEADROOM <= m->buf_len) ?
+			RTE_PKTMBUF_HEADROOM : m->buf_len;
+	m->data_off = buf_ofs;
+
+	m->data_len = 0;
+}
+
+/*
+ * This function is called after packets have been transimited. It fetchs mbuf
+ * from vpool->pool, detached it and put into vpool->ring. It also update the
+ * used index and kick the guest if necessary.
+ */
+static inline uint32_t __attribute__((always_inline))
+txmbuf_clean_zcp(struct virtio_net *dev, struct vpool *vpool)
+{
+	struct rte_mbuf *mbuf;
+	struct vhost_virtqueue *vq = dev->virtqueue[VIRTIO_TXQ];
+	uint32_t used_idx = vq->last_used_idx & (vq->size - 1);
+	uint32_t index = 0;
+	uint32_t mbuf_count = rte_mempool_count(vpool->pool);
+
+	LOG_DEBUG(VHOST_DATA,
+		"(%"PRIu64") in txmbuf_clean_zcp: mbuf count in mempool before "
+		"clean is: %d\n",
+		dev->device_fh, mbuf_count);
+	LOG_DEBUG(VHOST_DATA,
+		"(%"PRIu64") in txmbuf_clean_zcp: mbuf count in  ring before "
+		"clean  is : %d\n",
+		dev->device_fh, rte_ring_count(vpool->ring));
+
+	for (index = 0; index < mbuf_count; index++) {
+		mbuf = __rte_mbuf_raw_alloc(vpool->pool);
+		if (likely(RTE_MBUF_INDIRECT(mbuf)))
+			pktmbuf_detach_zcp(mbuf);
+		rte_ring_sp_enqueue(vpool->ring, mbuf);
+
+		/* Update used index buffer information. */
+		vq->used->ring[used_idx].id = MBUF_HEADROOM_UINT32(mbuf);
+		vq->used->ring[used_idx].len = 0;
+
+		used_idx = (used_idx + 1) & (vq->size - 1);
+	}
+
+	LOG_DEBUG(VHOST_DATA,
+		"(%"PRIu64") in txmbuf_clean_zcp: mbuf count in mempool after "
+		"clean is: %d\n",
+		dev->device_fh, rte_mempool_count(vpool->pool));
+	LOG_DEBUG(VHOST_DATA,
+		"(%"PRIu64") in txmbuf_clean_zcp: mbuf count in  ring after "
+		"clean  is : %d\n",
+		dev->device_fh, rte_ring_count(vpool->ring));
+	LOG_DEBUG(VHOST_DATA,
+		"(%"PRIu64") in txmbuf_clean_zcp: before updated "
+		"vq->last_used_idx:%d\n",
+		dev->device_fh, vq->last_used_idx);
+
+	vq->last_used_idx += mbuf_count;
+
+	LOG_DEBUG(VHOST_DATA,
+		"(%"PRIu64") in txmbuf_clean_zcp: after updated "
+		"vq->last_used_idx:%d\n",
+		dev->device_fh, vq->last_used_idx);
+
+	rte_compiler_barrier();
+
+	*(volatile uint16_t *)&vq->used->idx += mbuf_count;
+
+	/* Kick guest if required. */
+	if (!(vq->avail->flags & VRING_AVAIL_F_NO_INTERRUPT))
+		eventfd_write((int)vq->kickfd, 1);
+
+	return 0;
+}
+
+/*
+ * This function is called when a virtio device is destroy.
+ * It fetchs mbuf from vpool->pool, and detached it, and put into vpool->ring.
+ */
+static void mbuf_destroy_zcp(struct vpool *vpool)
+{
+	struct rte_mbuf *mbuf = NULL;
+	uint32_t index, mbuf_count = rte_mempool_count(vpool->pool);
+
+	LOG_DEBUG(VHOST_CONFIG,
+		"in mbuf_destroy_zcp: mbuf count in mempool before "
+		"mbuf_destroy_zcp is: %d\n",
+		mbuf_count);
+	LOG_DEBUG(VHOST_CONFIG,
+		"in mbuf_destroy_zcp: mbuf count in  ring before "
+		"mbuf_destroy_zcp  is : %d\n",
+		rte_ring_count(vpool->ring));
+
+	for (index = 0; index < mbuf_count; index++) {
+		mbuf = __rte_mbuf_raw_alloc(vpool->pool);
+		if (likely(mbuf != NULL)) {
+			if (likely(RTE_MBUF_INDIRECT(mbuf)))
+				pktmbuf_detach_zcp(mbuf);
+			rte_ring_sp_enqueue(vpool->ring, (void *)mbuf);
+		}
+	}
+
+	LOG_DEBUG(VHOST_CONFIG,
+		"in mbuf_destroy_zcp: mbuf count in mempool after "
+		"mbuf_destroy_zcp is: %d\n",
+		rte_mempool_count(vpool->pool));
+	LOG_DEBUG(VHOST_CONFIG,
+		"in mbuf_destroy_zcp: mbuf count in ring after "
+		"mbuf_destroy_zcp is : %d\n",
+		rte_ring_count(vpool->ring));
+}
+
+/*
+ * This function update the use flag and counter.
+ */
+static inline uint32_t __attribute__((always_inline))
+virtio_dev_rx_zcp(struct virtio_net *dev, struct rte_mbuf **pkts,
+	uint32_t count)
+{
+	struct vhost_virtqueue *vq;
+	struct vring_desc *desc;
+	struct rte_mbuf *buff;
+	/* The virtio_hdr is initialised to 0. */
+	struct virtio_net_hdr_mrg_rxbuf virtio_hdr
+		= {{0, 0, 0, 0, 0, 0}, 0};
+	uint64_t buff_hdr_addr = 0;
+	uint32_t head[MAX_PKT_BURST], packet_len = 0;
+	uint32_t head_idx, packet_success = 0;
+	uint16_t res_cur_idx;
+
+	LOG_DEBUG(VHOST_DATA, "(%"PRIu64") virtio_dev_rx()\n", dev->device_fh);
+
+	if (count == 0)
+		return 0;
+
+	vq = dev->virtqueue[VIRTIO_RXQ];
+	count = (count > MAX_PKT_BURST) ? MAX_PKT_BURST : count;
+
+	res_cur_idx = vq->last_used_idx;
+	LOG_DEBUG(VHOST_DATA, "(%"PRIu64") Current Index %d| End Index %d\n",
+		dev->device_fh, res_cur_idx, res_cur_idx + count);
+
+	/* Retrieve all of the head indexes first to avoid caching issues. */
+	for (head_idx = 0; head_idx < count; head_idx++)
+		head[head_idx] = MBUF_HEADROOM_UINT32(pkts[head_idx]);
+
+	/*Prefetch descriptor index. */
+	rte_prefetch0(&vq->desc[head[packet_success]]);
+
+	while (packet_success != count) {
+		/* Get descriptor from available ring */
+		desc = &vq->desc[head[packet_success]];
+
+		buff = pkts[packet_success];
+		LOG_DEBUG(VHOST_DATA,
+			"(%"PRIu64") in dev_rx_zcp: update the used idx for "
+			"pkt[%d] descriptor idx: %d\n",
+			dev->device_fh, packet_success,
+			MBUF_HEADROOM_UINT32(buff));
+
+		PRINT_PACKET(dev,
+			(uintptr_t)(((uint64_t)(uintptr_t)buff->buf_addr)
+			+ RTE_PKTMBUF_HEADROOM),
+			rte_pktmbuf_data_len(buff), 0);
+
+		/* Buffer address translation for virtio header. */
+		buff_hdr_addr = gpa_to_vva(dev, desc->addr);
+		packet_len = rte_pktmbuf_data_len(buff) + vq->vhost_hlen;
+
+		/*
+		 * If the descriptors are chained the header and data are
+		 * placed in separate buffers.
+		 */
+		if (desc->flags & VRING_DESC_F_NEXT) {
+			desc->len = vq->vhost_hlen;
+			desc = &vq->desc[desc->next];
+			desc->len = rte_pktmbuf_data_len(buff);
+		} else {
+			desc->len = packet_len;
+		}
+
+		/* Update used ring with desc information */
+		vq->used->ring[res_cur_idx & (vq->size - 1)].id
+			= head[packet_success];
+		vq->used->ring[res_cur_idx & (vq->size - 1)].len
+			= packet_len;
+		res_cur_idx++;
+		packet_success++;
+
+		/* A header is required per buffer. */
+		rte_memcpy((void *)(uintptr_t)buff_hdr_addr,
+			(const void *)&virtio_hdr, vq->vhost_hlen);
+
+		PRINT_PACKET(dev, (uintptr_t)buff_hdr_addr, vq->vhost_hlen, 1);
+
+		if (likely(packet_success < count)) {
+			/* Prefetch descriptor index. */
+			rte_prefetch0(&vq->desc[head[packet_success]]);
+		}
+	}
+
+	rte_compiler_barrier();
+
+	LOG_DEBUG(VHOST_DATA,
+		"(%"PRIu64") in dev_rx_zcp: before update used idx: "
+		"vq.last_used_idx: %d, vq->used->idx: %d\n",
+		dev->device_fh, vq->last_used_idx, vq->used->idx);
+
+	*(volatile uint16_t *)&vq->used->idx += count;
+	vq->last_used_idx += count;
+
+	LOG_DEBUG(VHOST_DATA,
+		"(%"PRIu64") in dev_rx_zcp: after  update used idx: "
+		"vq.last_used_idx: %d, vq->used->idx: %d\n",
+		dev->device_fh, vq->last_used_idx, vq->used->idx);
+
+	/* Kick the guest if necessary. */
+	if (!(vq->avail->flags & VRING_AVAIL_F_NO_INTERRUPT))
+		eventfd_write((int)vq->kickfd, 1);
+
+	return count;
+}
+
+/*
+ * This function routes the TX packet to the correct interface.
+ * This may be a local device or the physical port.
+ */
+static inline void __attribute__((always_inline))
+virtio_tx_route_zcp(struct virtio_net *dev, struct rte_mbuf *m,
+	uint32_t desc_idx, uint8_t need_copy)
+{
+	struct mbuf_table *tx_q;
+	struct rte_mbuf **m_table;
+	struct rte_mbuf *mbuf = NULL;
+	unsigned len, ret, offset = 0;
+	struct vpool *vpool;
+	struct virtio_net_data_ll *dev_ll = ll_root_used;
+	struct ether_hdr *pkt_hdr = rte_pktmbuf_mtod(m, struct ether_hdr *);
+	uint16_t vlan_tag = (uint16_t)vlan_tags[(uint16_t)dev->device_fh];
+
+	/*Add packet to the port tx queue*/
+	tx_q = &tx_queue_zcp[(uint16_t)dev->vmdq_rx_q];
+	len = tx_q->len;
+
+	/* Allocate an mbuf and populate the structure. */
+	vpool = &vpool_array[MAX_QUEUES + (uint16_t)dev->vmdq_rx_q];
+	rte_ring_sc_dequeue(vpool->ring, (void **)&mbuf);
+	if (unlikely(mbuf == NULL)) {
+		struct vhost_virtqueue *vq = dev->virtqueue[VIRTIO_TXQ];
+		RTE_LOG(ERR, VHOST_DATA,
+			"(%"PRIu64") Failed to allocate memory for mbuf.\n",
+			dev->device_fh);
+		put_desc_to_used_list_zcp(vq, desc_idx);
+		return;
+	}
+
+	if (vm2vm_mode == VM2VM_HARDWARE) {
+		/* Avoid using a vlan tag from any vm for external pkt, such as
+		 * vlan_tags[dev->device_fh], oterwise, it conflicts when pool
+		 * selection, MAC address determines it as an external pkt
+		 * which should go to network, while vlan tag determine it as
+		 * a vm2vm pkt should forward to another vm. Hardware confuse
+		 * such a ambiguous situation, so pkt will lost.
+		 */
+		vlan_tag = external_pkt_default_vlan_tag;
+		while (dev_ll != NULL) {
+			if (likely(dev_ll->dev->ready == DEVICE_RX) &&
+				ether_addr_cmp(&(pkt_hdr->d_addr),
+				&dev_ll->dev->mac_address)) {
+
+				/*
+				 * Drop the packet if the TX packet is destined
+				 * for the TX device.
+				 */
+				if (unlikely(dev_ll->dev->device_fh
+					== dev->device_fh)) {
+					LOG_DEBUG(VHOST_DATA,
+					"(%"PRIu64") TX: Source and destination"
+					"MAC addresses are the same. Dropping "
+					"packet.\n",
+					dev_ll->dev->device_fh);
+					MBUF_HEADROOM_UINT32(mbuf)
+						= (uint32_t)desc_idx;
+					__rte_mbuf_raw_free(mbuf);
+					return;
+				}
+
+				/*
+				 * Packet length offset 4 bytes for HW vlan
+				 * strip when L2 switch back.
+				 */
+				offset = 4;
+				vlan_tag =
+				(uint16_t)
+				vlan_tags[(uint16_t)dev_ll->dev->device_fh];
+
+				LOG_DEBUG(VHOST_DATA,
+				"(%"PRIu64") TX: pkt to local VM device id:"
+				"(%"PRIu64") vlan tag: %d.\n",
+				dev->device_fh, dev_ll->dev->device_fh,
+				vlan_tag);
+
+				break;
+			}
+			dev_ll = dev_ll->next;
+		}
+	}
+
+	mbuf->nb_segs = m->nb_segs;
+	mbuf->next = m->next;
+	mbuf->data_len = m->data_len + offset;
+	mbuf->pkt_len = mbuf->data_len;
+	if (unlikely(need_copy)) {
+		/* Copy the packet contents to the mbuf. */
+		rte_memcpy(rte_pktmbuf_mtod(mbuf, void *),
+			rte_pktmbuf_mtod(m, void *),
+			m->data_len);
+	} else {
+		mbuf->data_off = m->data_off;
+		mbuf->buf_physaddr = m->buf_physaddr;
+		mbuf->buf_addr = m->buf_addr;
+	}
+	mbuf->ol_flags = PKT_TX_VLAN_PKT;
+	mbuf->vlan_tci = vlan_tag;
+	mbuf->l2_len = sizeof(struct ether_hdr);
+	mbuf->l3_len = sizeof(struct ipv4_hdr);
+	MBUF_HEADROOM_UINT32(mbuf) = (uint32_t)desc_idx;
+
+	tx_q->m_table[len] = mbuf;
+	len++;
+
+	LOG_DEBUG(VHOST_DATA,
+		"(%"PRIu64") in tx_route_zcp: pkt: nb_seg: %d, next:%s\n",
+		dev->device_fh,
+		mbuf->nb_segs,
+		(mbuf->next == NULL) ? "null" : "non-null");
+
+	if (enable_stats) {
+		dev_statistics[dev->device_fh].tx_total++;
+		dev_statistics[dev->device_fh].tx++;
+	}
+
+	if (unlikely(len == MAX_PKT_BURST)) {
+		m_table = (struct rte_mbuf **)tx_q->m_table;
+		ret = rte_eth_tx_burst(ports[0],
+			(uint16_t)tx_q->txq_id, m_table, (uint16_t) len);
+
+		/*
+		 * Free any buffers not handled by TX and update
+		 * the port stats.
+		 */
+		if (unlikely(ret < len)) {
+			do {
+				rte_pktmbuf_free(m_table[ret]);
+			} while (++ret < len);
+		}
+
+		len = 0;
+		txmbuf_clean_zcp(dev, vpool);
+	}
+
+	tx_q->len = len;
+
+	return;
+}
+
+/*
+ * This function TX all available packets in virtio TX queue for one
+ * virtio-net device. If it is first packet, it learns MAC address and
+ * setup VMDQ.
+ */
+static inline void __attribute__((always_inline))
+virtio_dev_tx_zcp(struct virtio_net *dev)
+{
+	struct rte_mbuf m;
+	struct vhost_virtqueue *vq;
+	struct vring_desc *desc;
+	uint64_t buff_addr = 0, phys_addr;
+	uint32_t head[MAX_PKT_BURST];
+	uint32_t i;
+	uint16_t free_entries, packet_success = 0;
+	uint16_t avail_idx;
+	uint8_t need_copy = 0;
+	hpa_type addr_type;
+
+	vq = dev->virtqueue[VIRTIO_TXQ];
+	avail_idx =  *((volatile uint16_t *)&vq->avail->idx);
+
+	/* If there are no available buffers then return. */
+	if (vq->last_used_idx_res == avail_idx)
+		return;
+
+	LOG_DEBUG(VHOST_DATA, "(%"PRIu64") virtio_dev_tx()\n", dev->device_fh);
+
+	/* Prefetch available ring to retrieve head indexes. */
+	rte_prefetch0(&vq->avail->ring[vq->last_used_idx_res & (vq->size - 1)]);
+
+	/* Get the number of free entries in the ring */
+	free_entries = (avail_idx - vq->last_used_idx_res);
+
+	/* Limit to MAX_PKT_BURST. */
+	free_entries
+		= (free_entries > MAX_PKT_BURST) ? MAX_PKT_BURST : free_entries;
+
+	LOG_DEBUG(VHOST_DATA, "(%"PRIu64") Buffers available %d\n",
+		dev->device_fh, free_entries);
+
+	/* Retrieve all of the head indexes first to avoid caching issues. */
+	for (i = 0; i < free_entries; i++)
+		head[i]
+			= vq->avail->ring[(vq->last_used_idx_res + i)
+			& (vq->size - 1)];
+
+	vq->last_used_idx_res += free_entries;
+
+	/* Prefetch descriptor index. */
+	rte_prefetch0(&vq->desc[head[packet_success]]);
+	rte_prefetch0(&vq->used->ring[vq->last_used_idx & (vq->size - 1)]);
+
+	while (packet_success < free_entries) {
+		desc = &vq->desc[head[packet_success]];
+
+		/* Discard first buffer as it is the virtio header */
+		desc = &vq->desc[desc->next];
+
+		/* Buffer address translation. */
+		buff_addr = gpa_to_vva(dev, desc->addr);
+		phys_addr = gpa_to_hpa(dev, desc->addr, desc->len, &addr_type);
+
+		if (likely(packet_success < (free_entries - 1)))
+			/* Prefetch descriptor index. */
+			rte_prefetch0(&vq->desc[head[packet_success + 1]]);
+
+		if (unlikely(addr_type == PHYS_ADDR_INVALID)) {
+			RTE_LOG(ERR, VHOST_DATA,
+				"(%"PRIu64") Invalid frame buffer address found"
+				"when TX packets!\n",
+				dev->device_fh);
+			packet_success++;
+			continue;
+		}
+
+		/* Prefetch buffer address. */
+		rte_prefetch0((void *)(uintptr_t)buff_addr);
+
+		/*
+		 * Setup dummy mbuf. This is copied to a real mbuf if
+		 * transmitted out the physical port.
+		 */
+		m.data_len = desc->len;
+		m.nb_segs = 1;
+		m.next = NULL;
+		m.data_off = 0;
+		m.buf_addr = (void *)(uintptr_t)buff_addr;
+		m.buf_physaddr = phys_addr;
+
+		/*
+		 * Check if the frame buffer address from guest crosses
+		 * sub-region or not.
+		 */
+		if (unlikely(addr_type == PHYS_ADDR_CROSS_SUBREG)) {
+			RTE_LOG(ERR, VHOST_DATA,
+				"(%"PRIu64") Frame buffer address cross "
+				"sub-regioin found when attaching TX frame "
+				"buffer address!\n",
+				dev->device_fh);
+			need_copy = 1;
+		} else
+			need_copy = 0;
+
+		PRINT_PACKET(dev, (uintptr_t)buff_addr, desc->len, 0);
+
+		/*
+		 * If this is the first received packet we need to learn
+		 * the MAC and setup VMDQ
+		 */
+		if (unlikely(dev->ready == DEVICE_MAC_LEARNING)) {
+			if (dev->remove || (link_vmdq(dev, &m) == -1)) {
+				/*
+				 * Discard frame if device is scheduled for
+				 * removal or a duplicate MAC address is found.
+				 */
+				packet_success += free_entries;
+				vq->last_used_idx += packet_success;
+				break;
+			}
+		}
+
+		virtio_tx_route_zcp(dev, &m, head[packet_success], need_copy);
+		packet_success++;
+	}
+}
+
+/*
+ * This function is called by each data core. It handles all RX/TX registered
+ * with the core. For TX the specific lcore linked list is used. For RX, MAC
+ * addresses are compared with all devices in the main linked list.
+ */
+static int
+switch_worker_zcp(__attribute__((unused)) void *arg)
+{
+	struct virtio_net *dev = NULL;
+	struct rte_mbuf *pkts_burst[MAX_PKT_BURST];
+	struct virtio_net_data_ll *dev_ll;
+	struct mbuf_table *tx_q;
+	volatile struct lcore_ll_info *lcore_ll;
+	const uint64_t drain_tsc
+		= (rte_get_tsc_hz() + US_PER_S - 1) / US_PER_S
+		* BURST_TX_DRAIN_US;
+	uint64_t prev_tsc, diff_tsc, cur_tsc, ret_count = 0;
+	unsigned ret;
+	const uint16_t lcore_id = rte_lcore_id();
+	uint16_t count_in_ring, rx_count = 0;
+
+	RTE_LOG(INFO, VHOST_DATA, "Procesing on Core %u started\n", lcore_id);
+
+	lcore_ll = lcore_info[lcore_id].lcore_ll;
+	prev_tsc = 0;
+
+	while (1) {
+		cur_tsc = rte_rdtsc();
+
+		/* TX burst queue drain */
+		diff_tsc = cur_tsc - prev_tsc;
+		if (unlikely(diff_tsc > drain_tsc)) {
+			/*
+			 * Get mbuf from vpool.pool and detach mbuf and
+			 * put back into vpool.ring.
+			 */
+			dev_ll = lcore_ll->ll_root_used;
+			while ((dev_ll != NULL) && (dev_ll->dev != NULL)) {
+				/* Get virtio device ID */
+				dev = dev_ll->dev;
+
+				if (likely(!dev->remove)) {
+					tx_q = &tx_queue_zcp[(uint16_t)dev->vmdq_rx_q];
+					if (tx_q->len) {
+						LOG_DEBUG(VHOST_DATA,
+						"TX queue drained after timeout"
+						" with burst size %u\n",
+						tx_q->len);
+
+						/*
+						 * Tx any packets in the queue
+						 */
+						ret = rte_eth_tx_burst(
+							ports[0],
+							(uint16_t)tx_q->txq_id,
+							(struct rte_mbuf **)
+							tx_q->m_table,
+							(uint16_t)tx_q->len);
+						if (unlikely(ret < tx_q->len)) {
+							do {
+								rte_pktmbuf_free(
+									tx_q->m_table[ret]);
+							} while (++ret < tx_q->len);
+						}
+						tx_q->len = 0;
+
+						txmbuf_clean_zcp(dev,
+							&vpool_array[MAX_QUEUES+dev->vmdq_rx_q]);
+					}
+				}
+				dev_ll = dev_ll->next;
+			}
+			prev_tsc = cur_tsc;
+		}
+
+		rte_prefetch0(lcore_ll->ll_root_used);
+
+		/*
+		 * Inform the configuration core that we have exited the linked
+		 * list and that no devices are in use if requested.
+		 */
+		if (lcore_ll->dev_removal_flag == REQUEST_DEV_REMOVAL)
+			lcore_ll->dev_removal_flag = ACK_DEV_REMOVAL;
+
+		/* Process devices */
+		dev_ll = lcore_ll->ll_root_used;
+
+		while ((dev_ll != NULL) && (dev_ll->dev != NULL)) {
+			dev = dev_ll->dev;
+			if (unlikely(dev->remove)) {
+				dev_ll = dev_ll->next;
+				unlink_vmdq(dev);
+				dev->ready = DEVICE_SAFE_REMOVE;
+				continue;
+			}
+
+			if (likely(dev->ready == DEVICE_RX)) {
+				uint32_t index = dev->vmdq_rx_q;
+				uint16_t i;
+				count_in_ring
+				= rte_ring_count(vpool_array[index].ring);
+				uint16_t free_entries
+				= (uint16_t)get_available_ring_num_zcp(dev);
+
+				/*
+				 * Attach all mbufs in vpool.ring and put back
+				 * into vpool.pool.
+				 */
+				for (i = 0;
+				i < RTE_MIN(free_entries,
+				RTE_MIN(count_in_ring, MAX_PKT_BURST));
+				i++)
+					attach_rxmbuf_zcp(dev);
+
+				/* Handle guest RX */
+				rx_count = rte_eth_rx_burst(ports[0],
+					(uint16_t)dev->vmdq_rx_q, pkts_burst,
+					MAX_PKT_BURST);
+
+				if (rx_count) {
+					ret_count = virtio_dev_rx_zcp(dev,
+							pkts_burst, rx_count);
+					if (enable_stats) {
+						dev_statistics[dev->device_fh].rx_total
+							+= rx_count;
+						dev_statistics[dev->device_fh].rx
+							+= ret_count;
+					}
+					while (likely(rx_count)) {
+						rx_count--;
+						pktmbuf_detach_zcp(
+							pkts_burst[rx_count]);
+						rte_ring_sp_enqueue(
+							vpool_array[index].ring,
+							(void *)pkts_burst[rx_count]);
+					}
+				}
+			}
+
+			if (likely(!dev->remove))
+				/* Handle guest TX */
+				virtio_dev_tx_zcp(dev);
+
+			/* Move to the next device in the list */
+			dev_ll = dev_ll->next;
+		}
+	}
+
+	return 0;
+}
+
+
+/*
+ * Add an entry to a used linked list. A free entry must first be found
+ * in the free linked list using get_data_ll_free_entry();
+ */
+static void
+add_data_ll_entry(struct virtio_net_data_ll **ll_root_addr,
+	struct virtio_net_data_ll *ll_dev)
+{
+	struct virtio_net_data_ll *ll = *ll_root_addr;
+
+	/* Set next as NULL and use a compiler barrier to avoid reordering. */
+	ll_dev->next = NULL;
+	rte_compiler_barrier();
+
+	/* If ll == NULL then this is the first device. */
+	if (ll) {
+		/* Increment to the tail of the linked list. */
+		while ((ll->next != NULL) )
+			ll = ll->next;
+
+		ll->next = ll_dev;
+	} else {
+		*ll_root_addr = ll_dev;
+	}
+}
+
+/*
+ * Remove an entry from a used linked list. The entry must then be added to
+ * the free linked list using put_data_ll_free_entry().
+ */
+static void
+rm_data_ll_entry(struct virtio_net_data_ll **ll_root_addr,
+	struct virtio_net_data_ll *ll_dev,
+	struct virtio_net_data_ll *ll_dev_last)
+{
+	struct virtio_net_data_ll *ll = *ll_root_addr;
+
+	if (unlikely((ll == NULL) || (ll_dev == NULL)))
+		return;
+
+	if (ll_dev == ll)
+		*ll_root_addr = ll_dev->next;
+	else
+		if (likely(ll_dev_last != NULL))
+			ll_dev_last->next = ll_dev->next;
+		else
+			RTE_LOG(ERR, VHOST_CONFIG, "Remove entry form ll failed.\n");
+}
+
+/*
+ * Find and return an entry from the free linked list.
+ */
+static struct virtio_net_data_ll *
+get_data_ll_free_entry(struct virtio_net_data_ll **ll_root_addr)
+{
+	struct virtio_net_data_ll *ll_free = *ll_root_addr;
+	struct virtio_net_data_ll *ll_dev;
+
+	if (ll_free == NULL)
+		return NULL;
+
+	ll_dev = ll_free;
+	*ll_root_addr = ll_free->next;
+
+	return ll_dev;
+}
+
+/*
+ * Place an entry back on to the free linked list.
+ */
+static void
+put_data_ll_free_entry(struct virtio_net_data_ll **ll_root_addr,
+	struct virtio_net_data_ll *ll_dev)
+{
+	struct virtio_net_data_ll *ll_free = *ll_root_addr;
+
+	if (ll_dev == NULL)
+		return;
+
+	ll_dev->next = ll_free;
+	*ll_root_addr = ll_dev;
+}
+
+/*
+ * Creates a linked list of a given size.
+ */
+static struct virtio_net_data_ll *
+alloc_data_ll(uint32_t size)
+{
+	struct virtio_net_data_ll *ll_new;
+	uint32_t i;
+
+	/* Malloc and then chain the linked list. */
+	ll_new = malloc(size * sizeof(struct virtio_net_data_ll));
+	if (ll_new == NULL) {
+		RTE_LOG(ERR, VHOST_CONFIG, "Failed to allocate memory for ll_new.\n");
+		return NULL;
+	}
+
+	for (i = 0; i < size - 1; i++) {
+		ll_new[i].dev = NULL;
+		ll_new[i].next = &ll_new[i+1];
+	}
+	ll_new[i].next = NULL;
+
+	return (ll_new);
+}
+
+/*
+ * Create the main linked list along with each individual cores linked list. A used and a free list
+ * are created to manage entries.
+ */
+static int
+init_data_ll (void)
+{
+	int lcore;
+
+	RTE_LCORE_FOREACH_SLAVE(lcore) {
+		lcore_info[lcore].lcore_ll = malloc(sizeof(struct lcore_ll_info));
+		if (lcore_info[lcore].lcore_ll == NULL) {
+			RTE_LOG(ERR, VHOST_CONFIG, "Failed to allocate memory for lcore_ll.\n");
+			return -1;
+		}
+
+		lcore_info[lcore].lcore_ll->device_num = 0;
+		lcore_info[lcore].lcore_ll->dev_removal_flag = ACK_DEV_REMOVAL;
+		lcore_info[lcore].lcore_ll->ll_root_used = NULL;
+		if (num_devices % num_switching_cores)
+			lcore_info[lcore].lcore_ll->ll_root_free = alloc_data_ll((num_devices / num_switching_cores) + 1);
+		else
+			lcore_info[lcore].lcore_ll->ll_root_free = alloc_data_ll(num_devices / num_switching_cores);
+	}
+
+	/* Allocate devices up to a maximum of MAX_DEVICES. */
+	ll_root_free = alloc_data_ll(MIN((num_devices), MAX_DEVICES));
+
+	return 0;
+}
+
+/*
+ * Set virtqueue flags so that we do not receive interrupts.
+ */
+static void
+set_irq_status (struct virtio_net *dev)
+{
+	dev->virtqueue[VIRTIO_RXQ]->used->flags = VRING_USED_F_NO_NOTIFY;
+	dev->virtqueue[VIRTIO_TXQ]->used->flags = VRING_USED_F_NO_NOTIFY;
+}
+
+/*
+ * Remove a device from the specific data core linked list and from the main linked list. Synchonization
+ * occurs through the use of the lcore dev_removal_flag. Device is made volatile here to avoid re-ordering
+ * of dev->remove=1 which can cause an infinite loop in the rte_pause loop.
+ */
+static void
+destroy_device (volatile struct virtio_net *dev)
+{
+	struct virtio_net_data_ll *ll_lcore_dev_cur;
+	struct virtio_net_data_ll *ll_main_dev_cur;
+	struct virtio_net_data_ll *ll_lcore_dev_last = NULL;
+	struct virtio_net_data_ll *ll_main_dev_last = NULL;
+	int lcore;
+
+	dev->flags &= ~VIRTIO_DEV_RUNNING;
+
+	/*set the remove flag. */
+	dev->remove = 1;
+
+	while(dev->ready != DEVICE_SAFE_REMOVE) {
+		rte_pause();
+	}
+
+	/* Search for entry to be removed from lcore ll */
+	ll_lcore_dev_cur = lcore_info[dev->coreid].lcore_ll->ll_root_used;
+	while (ll_lcore_dev_cur != NULL) {
+		if (ll_lcore_dev_cur->dev == dev) {
+			break;
+		} else {
+			ll_lcore_dev_last = ll_lcore_dev_cur;
+			ll_lcore_dev_cur = ll_lcore_dev_cur->next;
+		}
+	}
+
+	if (ll_lcore_dev_cur == NULL) {
+		RTE_LOG(ERR, VHOST_CONFIG,
+			"(%"PRIu64") Failed to find the dev to be destroy.\n",
+			dev->device_fh);
+		return;
+	}
+
+	/* Search for entry to be removed from main ll */
+	ll_main_dev_cur = ll_root_used;
+	ll_main_dev_last = NULL;
+	while (ll_main_dev_cur != NULL) {
+		if (ll_main_dev_cur->dev == dev) {
+			break;
+		} else {
+			ll_main_dev_last = ll_main_dev_cur;
+			ll_main_dev_cur = ll_main_dev_cur->next;
+		}
+	}
+
+	/* Remove entries from the lcore and main ll. */
+	rm_data_ll_entry(&lcore_info[ll_lcore_dev_cur->dev->coreid].lcore_ll->ll_root_used, ll_lcore_dev_cur, ll_lcore_dev_last);
+	rm_data_ll_entry(&ll_root_used, ll_main_dev_cur, ll_main_dev_last);
+
+	/* Set the dev_removal_flag on each lcore. */
+	RTE_LCORE_FOREACH_SLAVE(lcore) {
+		lcore_info[lcore].lcore_ll->dev_removal_flag = REQUEST_DEV_REMOVAL;
+	}
+
+	/*
+	 * Once each core has set the dev_removal_flag to ACK_DEV_REMOVAL we can be sure that
+	 * they can no longer access the device removed from the linked lists and that the devices
+	 * are no longer in use.
+	 */
+	RTE_LCORE_FOREACH_SLAVE(lcore) {
+		while (lcore_info[lcore].lcore_ll->dev_removal_flag != ACK_DEV_REMOVAL) {
+			rte_pause();
+		}
+	}
+
+	/* Add the entries back to the lcore and main free ll.*/
+	put_data_ll_free_entry(&lcore_info[ll_lcore_dev_cur->dev->coreid].lcore_ll->ll_root_free, ll_lcore_dev_cur);
+	put_data_ll_free_entry(&ll_root_free, ll_main_dev_cur);
+
+	/* Decrement number of device on the lcore. */
+	lcore_info[ll_lcore_dev_cur->dev->coreid].lcore_ll->device_num--;
+
+	RTE_LOG(INFO, VHOST_DATA, "(%"PRIu64") Device has been removed from data core\n", dev->device_fh);
+
+	if (zero_copy) {
+		struct vpool *vpool = &vpool_array[dev->vmdq_rx_q];
+
+		/* Stop the RX queue. */
+		if (rte_eth_dev_rx_queue_stop(ports[0], dev->vmdq_rx_q) != 0) {
+			LOG_DEBUG(VHOST_CONFIG,
+				"(%"PRIu64") In destroy_device: Failed to stop "
+				"rx queue:%d\n",
+				dev->device_fh,
+				dev->vmdq_rx_q);
+		}
+
+		LOG_DEBUG(VHOST_CONFIG,
+			"(%"PRIu64") in destroy_device: Start put mbuf in "
+			"mempool back to ring for RX queue: %d\n",
+			dev->device_fh, dev->vmdq_rx_q);
+
+		mbuf_destroy_zcp(vpool);
+
+		/* Stop the TX queue. */
+		if (rte_eth_dev_tx_queue_stop(ports[0], dev->vmdq_rx_q) != 0) {
+			LOG_DEBUG(VHOST_CONFIG,
+				"(%"PRIu64") In destroy_device: Failed to "
+				"stop tx queue:%d\n",
+				dev->device_fh, dev->vmdq_rx_q);
+		}
+
+		vpool = &vpool_array[dev->vmdq_rx_q + MAX_QUEUES];
+
+		LOG_DEBUG(VHOST_CONFIG,
+			"(%"PRIu64") destroy_device: Start put mbuf in mempool "
+			"back to ring for TX queue: %d, dev:(%"PRIu64")\n",
+			dev->device_fh, (dev->vmdq_rx_q + MAX_QUEUES),
+			dev->device_fh);
+
+		mbuf_destroy_zcp(vpool);
+	}
+
+}
+
+/*
+ * A new device is added to a data core. First the device is added to the main linked list
+ * and the allocated to a specific data core.
+ */
+static int
+new_device (struct virtio_net *dev)
+{
+	struct virtio_net_data_ll *ll_dev;
+	int lcore, core_add = 0;
+	uint32_t device_num_min = num_devices;
+
+	/* Add device to main ll */
+	ll_dev = get_data_ll_free_entry(&ll_root_free);
+	if (ll_dev == NULL) {
+		RTE_LOG(INFO, VHOST_DATA, "(%"PRIu64") No free entry found in linked list. Device limit "
+			"of %d devices per core has been reached\n",
+			dev->device_fh, num_devices);
+		return -1;
+	}
+	ll_dev->dev = dev;
+	add_data_ll_entry(&ll_root_used, ll_dev);
+	ll_dev->dev->vmdq_rx_q
+		= ll_dev->dev->device_fh * (num_queues / num_devices);
+
+	if (zero_copy) {
+		uint32_t index = ll_dev->dev->vmdq_rx_q;
+		uint32_t count_in_ring, i;
+		struct mbuf_table *tx_q;
+
+		count_in_ring = rte_ring_count(vpool_array[index].ring);
+
+		LOG_DEBUG(VHOST_CONFIG,
+			"(%"PRIu64") in new_device: mbuf count in mempool "
+			"before attach is: %d\n",
+			dev->device_fh,
+			rte_mempool_count(vpool_array[index].pool));
+		LOG_DEBUG(VHOST_CONFIG,
+			"(%"PRIu64") in new_device: mbuf count in  ring "
+			"before attach  is : %d\n",
+			dev->device_fh, count_in_ring);
+
+		/*
+		 * Attach all mbufs in vpool.ring and put back intovpool.pool.
+		 */
+		for (i = 0; i < count_in_ring; i++)
+			attach_rxmbuf_zcp(dev);
+
+		LOG_DEBUG(VHOST_CONFIG, "(%"PRIu64") in new_device: mbuf count in "
+			"mempool after attach is: %d\n",
+			dev->device_fh,
+			rte_mempool_count(vpool_array[index].pool));
+		LOG_DEBUG(VHOST_CONFIG, "(%"PRIu64") in new_device: mbuf count in "
+			"ring after attach  is : %d\n",
+			dev->device_fh,
+			rte_ring_count(vpool_array[index].ring));
+
+		tx_q = &tx_queue_zcp[(uint16_t)dev->vmdq_rx_q];
+		tx_q->txq_id = dev->vmdq_rx_q;
+
+		if (rte_eth_dev_tx_queue_start(ports[0], dev->vmdq_rx_q) != 0) {
+			struct vpool *vpool = &vpool_array[dev->vmdq_rx_q];
+
+			LOG_DEBUG(VHOST_CONFIG,
+				"(%"PRIu64") In new_device: Failed to start "
+				"tx queue:%d\n",
+				dev->device_fh, dev->vmdq_rx_q);
+
+			mbuf_destroy_zcp(vpool);
+			return -1;
+		}
+
+		if (rte_eth_dev_rx_queue_start(ports[0], dev->vmdq_rx_q) != 0) {
+			struct vpool *vpool = &vpool_array[dev->vmdq_rx_q];
+
+			LOG_DEBUG(VHOST_CONFIG,
+				"(%"PRIu64") In new_device: Failed to start "
+				"rx queue:%d\n",
+				dev->device_fh, dev->vmdq_rx_q);
+
+			/* Stop the TX queue. */
+			if (rte_eth_dev_tx_queue_stop(ports[0],
+				dev->vmdq_rx_q) != 0) {
+				LOG_DEBUG(VHOST_CONFIG,
+					"(%"PRIu64") In new_device: Failed to "
+					"stop tx queue:%d\n",
+					dev->device_fh, dev->vmdq_rx_q);
+			}
+
+			mbuf_destroy_zcp(vpool);
+			return -1;
+		}
+
+	}
+
+	/*reset ready flag*/
+	dev->ready = DEVICE_MAC_LEARNING;
+	dev->remove = 0;
+
+	/* Find a suitable lcore to add the device. */
+	RTE_LCORE_FOREACH_SLAVE(lcore) {
+		if (lcore_info[lcore].lcore_ll->device_num < device_num_min) {
+			device_num_min = lcore_info[lcore].lcore_ll->device_num;
+			core_add = lcore;
+		}
+	}
+	/* Add device to lcore ll */
+	ll_dev->dev->coreid = core_add;
+	ll_dev = get_data_ll_free_entry(&lcore_info[ll_dev->dev->coreid].lcore_ll->ll_root_free);
+	if (ll_dev == NULL) {
+		RTE_LOG(INFO, VHOST_DATA, "(%"PRIu64") Failed to add device to data core\n", dev->device_fh);
+		dev->ready = DEVICE_SAFE_REMOVE;
+		destroy_device(dev);
+		return -1;
+	}
+	ll_dev->dev = dev;
+	add_data_ll_entry(&lcore_info[ll_dev->dev->coreid].lcore_ll->ll_root_used, ll_dev);
+
+	/* Initialize device stats */
+	memset(&dev_statistics[dev->device_fh], 0, sizeof(struct device_statistics));
+
+	/* Disable notifications. */
+	set_irq_status(dev);
+	lcore_info[ll_dev->dev->coreid].lcore_ll->device_num++;
+	dev->flags |= VIRTIO_DEV_RUNNING;
+
+	RTE_LOG(INFO, VHOST_DATA, "(%"PRIu64") Device has been added to data core %d\n", dev->device_fh, dev->coreid);
+
+	return 0;
+}
+
+/*
+ * These callback allow devices to be added to the data core when configuration
+ * has been fully complete.
+ */
+static const struct virtio_net_device_ops virtio_net_device_ops =
+{
+	.new_device =  new_device,
+	.destroy_device = destroy_device,
+};
+
+/*
+ * This is a thread will wake up after a period to print stats if the user has
+ * enabled them.
+ */
+static void
+print_stats(void)
+{
+	struct virtio_net_data_ll *dev_ll;
+	uint64_t tx_dropped, rx_dropped;
+	uint64_t tx, tx_total, rx, rx_total;
+	uint32_t device_fh;
+	const char clr[] = { 27, '[', '2', 'J', '\0' };
+	const char top_left[] = { 27, '[', '1', ';', '1', 'H','\0' };
+
+	while(1) {
+		sleep(enable_stats);
+
+		/* Clear screen and move to top left */
+		printf("%s%s", clr, top_left);
+
+		printf("\nDevice statistics ====================================");
+
+		dev_ll = ll_root_used;
+		while (dev_ll != NULL) {
+			device_fh = (uint32_t)dev_ll->dev->device_fh;
+			tx_total = dev_statistics[device_fh].tx_total;
+			tx = dev_statistics[device_fh].tx;
+			tx_dropped = tx_total - tx;
+			if (zero_copy == 0) {
+				rx_total = rte_atomic64_read(
+					&dev_statistics[device_fh].rx_total_atomic);
+				rx = rte_atomic64_read(
+					&dev_statistics[device_fh].rx_atomic);
+			} else {
+				rx_total = dev_statistics[device_fh].rx_total;
+				rx = dev_statistics[device_fh].rx;
+			}
+			rx_dropped = rx_total - rx;
+
+			printf("\nStatistics for device %"PRIu32" ------------------------------"
+					"\nTX total: 		%"PRIu64""
+					"\nTX dropped: 		%"PRIu64""
+					"\nTX successful: 		%"PRIu64""
+					"\nRX total: 		%"PRIu64""
+					"\nRX dropped: 		%"PRIu64""
+					"\nRX successful: 		%"PRIu64"",
+					device_fh,
+					tx_total,
+					tx_dropped,
+					tx,
+					rx_total,
+					rx_dropped,
+					rx);
+
+			dev_ll = dev_ll->next;
+		}
+		printf("\n======================================================\n");
+	}
+}
+
+static void
+setup_mempool_tbl(int socket, uint32_t index, char *pool_name,
+	char *ring_name, uint32_t nb_mbuf)
+{
+	uint16_t roomsize = VIRTIO_DESCRIPTOR_LEN_ZCP + RTE_PKTMBUF_HEADROOM;
+	vpool_array[index].pool
+		= rte_mempool_create(pool_name, nb_mbuf, MBUF_SIZE_ZCP,
+		MBUF_CACHE_SIZE_ZCP, sizeof(struct rte_pktmbuf_pool_private),
+		rte_pktmbuf_pool_init, (void *)(uintptr_t)roomsize,
+		rte_pktmbuf_init, NULL, socket, 0);
+	if (vpool_array[index].pool != NULL) {
+		vpool_array[index].ring
+			= rte_ring_create(ring_name,
+				rte_align32pow2(nb_mbuf + 1),
+				socket, RING_F_SP_ENQ | RING_F_SC_DEQ);
+		if (likely(vpool_array[index].ring != NULL)) {
+			LOG_DEBUG(VHOST_CONFIG,
+				"in setup_mempool_tbl: mbuf count in "
+				"mempool is: %d\n",
+				rte_mempool_count(vpool_array[index].pool));
+			LOG_DEBUG(VHOST_CONFIG,
+				"in setup_mempool_tbl: mbuf count in "
+				"ring   is: %d\n",
+				rte_ring_count(vpool_array[index].ring));
+		} else {
+			rte_exit(EXIT_FAILURE, "ring_create(%s) failed",
+				ring_name);
+		}
+
+		/* Need consider head room. */
+		vpool_array[index].buf_size = roomsize - RTE_PKTMBUF_HEADROOM;
+	} else {
+		rte_exit(EXIT_FAILURE, "mempool_create(%s) failed", pool_name);
+	}
+}
+
+
+/*
+ * Main function, does initialisation and calls the per-lcore functions. The CUSE
+ * device is also registered here to handle the IOCTLs.
+ */
+int
+MAIN(int argc, char *argv[])
+{
+	struct rte_mempool *mbuf_pool = NULL;
+	unsigned lcore_id, core_id = 0;
+	unsigned nb_ports, valid_num_ports;
+	int ret;
+	uint8_t portid, queue_id = 0;
+	static pthread_t tid;
+
+	/* init EAL */
+	ret = rte_eal_init(argc, argv);
+	if (ret < 0)
+		rte_exit(EXIT_FAILURE, "Error with EAL initialization\n");
+	argc -= ret;
+	argv += ret;
+
+	/* parse app arguments */
+	ret = us_vhost_parse_args(argc, argv);
+	if (ret < 0)
+		rte_exit(EXIT_FAILURE, "Invalid argument\n");
+
+	if (rte_eal_pci_probe() != 0)
+		rte_exit(EXIT_FAILURE, "Error with NIC driver initialization\n");
+
+	for (lcore_id = 0; lcore_id < RTE_MAX_LCORE; lcore_id ++)
+		if (rte_lcore_is_enabled(lcore_id))
+			lcore_ids[core_id ++] = lcore_id;
+
+	if (rte_lcore_count() > RTE_MAX_LCORE)
+		rte_exit(EXIT_FAILURE,"Not enough cores\n");
+
+	/*set the number of swithcing cores available*/
+	num_switching_cores = rte_lcore_count()-1;
+
+	/* Get the number of physical ports. */
+	nb_ports = rte_eth_dev_count();
+	if (nb_ports > RTE_MAX_ETHPORTS)
+		nb_ports = RTE_MAX_ETHPORTS;
+
+	/*
+	 * Update the global var NUM_PORTS and global array PORTS
+	 * and get value of var VALID_NUM_PORTS according to system ports number
+	 */
+	valid_num_ports = check_ports_num(nb_ports);
+
+	if ((valid_num_ports ==  0) || (valid_num_ports > MAX_SUP_PORTS)) {
+		RTE_LOG(INFO, VHOST_PORT, "Current enabled port number is %u,"
+			"but only %u port can be enabled\n",num_ports, MAX_SUP_PORTS);
+		return -1;
+	}
+
+	if (zero_copy == 0) {
+		/* Create the mbuf pool. */
+		mbuf_pool = rte_mempool_create(
+				"MBUF_POOL",
+				NUM_MBUFS_PER_PORT
+				* valid_num_ports,
+				MBUF_SIZE, MBUF_CACHE_SIZE,
+				sizeof(struct rte_pktmbuf_pool_private),
+				rte_pktmbuf_pool_init, NULL,
+				rte_pktmbuf_init, NULL,
+				rte_socket_id(), 0);
+		if (mbuf_pool == NULL)
+			rte_exit(EXIT_FAILURE, "Cannot create mbuf pool\n");
+
+		for (queue_id = 0; queue_id < MAX_QUEUES + 1; queue_id++)
+			vpool_array[queue_id].pool = mbuf_pool;
+
+		if (vm2vm_mode == VM2VM_HARDWARE) {
+			/* Enable VT loop back to let L2 switch to do it. */
+			vmdq_conf_default.rx_adv_conf.vmdq_rx_conf.enable_loop_back = 1;
+			LOG_DEBUG(VHOST_CONFIG,
+				"Enable loop back for L2 switch in vmdq.\n");
+		}
+	} else {
+		uint32_t nb_mbuf;
+		char pool_name[RTE_MEMPOOL_NAMESIZE];
+		char ring_name[RTE_MEMPOOL_NAMESIZE];
+
+		rx_conf_default.start_rx_per_q = (uint8_t)zero_copy;
+		rx_conf_default.rx_drop_en = 0;
+		tx_conf_default.start_tx_per_q = (uint8_t)zero_copy;
+		nb_mbuf = num_rx_descriptor
+			+ num_switching_cores * MBUF_CACHE_SIZE_ZCP
+			+ num_switching_cores * MAX_PKT_BURST;
+
+		for (queue_id = 0; queue_id < MAX_QUEUES; queue_id++) {
+			snprintf(pool_name, sizeof(pool_name),
+				"rxmbuf_pool_%u", queue_id);
+			snprintf(ring_name, sizeof(ring_name),
+				"rxmbuf_ring_%u", queue_id);
+			setup_mempool_tbl(rte_socket_id(), queue_id,
+				pool_name, ring_name, nb_mbuf);
+		}
+
+		nb_mbuf = num_tx_descriptor
+				+ num_switching_cores * MBUF_CACHE_SIZE_ZCP
+				+ num_switching_cores * MAX_PKT_BURST;
+
+		for (queue_id = 0; queue_id < MAX_QUEUES; queue_id++) {
+			snprintf(pool_name, sizeof(pool_name),
+				"txmbuf_pool_%u", queue_id);
+			snprintf(ring_name, sizeof(ring_name),
+				"txmbuf_ring_%u", queue_id);
+			setup_mempool_tbl(rte_socket_id(),
+				(queue_id + MAX_QUEUES),
+				pool_name, ring_name, nb_mbuf);
+		}
+
+		if (vm2vm_mode == VM2VM_HARDWARE) {
+			/* Enable VT loop back to let L2 switch to do it. */
+			vmdq_conf_default.rx_adv_conf.vmdq_rx_conf.enable_loop_back = 1;
+			LOG_DEBUG(VHOST_CONFIG,
+				"Enable loop back for L2 switch in vmdq.\n");
+		}
+	}
+	/* Set log level. */
+	rte_set_log_level(LOG_LEVEL);
+
+	/* initialize all ports */
+	for (portid = 0; portid < nb_ports; portid++) {
+		/* skip ports that are not enabled */
+		if ((enabled_port_mask & (1 << portid)) == 0) {
+			RTE_LOG(INFO, VHOST_PORT,
+				"Skipping disabled port %d\n", portid);
+			continue;
+		}
+		if (port_init(portid) != 0)
+			rte_exit(EXIT_FAILURE,
+				"Cannot initialize network ports\n");
+	}
+
+	/* Initialise all linked lists. */
+	if (init_data_ll() == -1)
+		rte_exit(EXIT_FAILURE, "Failed to initialize linked list\n");
+
+	/* Initialize device stats */
+	memset(&dev_statistics, 0, sizeof(dev_statistics));
+
+	/* Enable stats if the user option is set. */
+	if (enable_stats)
+		pthread_create(&tid, NULL, (void*)print_stats, NULL );
+
+	/* Launch all data cores. */
+	if (zero_copy == 0) {
+		RTE_LCORE_FOREACH_SLAVE(lcore_id) {
+			rte_eal_remote_launch(switch_worker,
+				mbuf_pool, lcore_id);
+		}
+	} else {
+		uint32_t count_in_mempool, index, i;
+		for (index = 0; index < 2*MAX_QUEUES; index++) {
+			/* For all RX and TX queues. */
+			count_in_mempool
+				= rte_mempool_count(vpool_array[index].pool);
+
+			/*
+			 * Transfer all un-attached mbufs from vpool.pool
+			 * to vpoo.ring.
+			 */
+			for (i = 0; i < count_in_mempool; i++) {
+				struct rte_mbuf *mbuf
+					= __rte_mbuf_raw_alloc(
+						vpool_array[index].pool);
+				rte_ring_sp_enqueue(vpool_array[index].ring,
+						(void *)mbuf);
+			}
+
+			LOG_DEBUG(VHOST_CONFIG,
+				"in MAIN: mbuf count in mempool at initial "
+				"is: %d\n", count_in_mempool);
+			LOG_DEBUG(VHOST_CONFIG,
+				"in MAIN: mbuf count in  ring at initial  is :"
+				" %d\n",
+				rte_ring_count(vpool_array[index].ring));
+		}
+
+		RTE_LCORE_FOREACH_SLAVE(lcore_id)
+			rte_eal_remote_launch(switch_worker_zcp, NULL,
+				lcore_id);
+	}
+
+	/* Register CUSE device to handle IOCTLs. */
+	ret = register_cuse_device((char*)&dev_basename, dev_index, get_virtio_net_callbacks());
+	if (ret != 0)
+		rte_exit(EXIT_FAILURE,"CUSE device setup failure.\n");
+
+	init_virtio_net(&virtio_net_device_ops);
+
+	/* Start CUSE session. */
+	start_cuse_session_loop();
+	return 0;
+
+}
+
diff --git a/lib/librte_vhost/main.h b/lib/librte_vhost/main.h
new file mode 100644
index 0000000..c15d938
--- /dev/null
+++ b/lib/librte_vhost/main.h
@@ -0,0 +1,86 @@
+/*-
+ *   BSD LICENSE
+ *
+ *   Copyright(c) 2010-2014 Intel Corporation. All rights reserved.
+ *   All rights reserved.
+ *
+ *   Redistribution and use in source and binary forms, with or without
+ *   modification, are permitted provided that the following conditions
+ *   are met:
+ *
+ *     * Redistributions of source code must retain the above copyright
+ *       notice, this list of conditions and the following disclaimer.
+ *     * Redistributions in binary form must reproduce the above copyright
+ *       notice, this list of conditions and the following disclaimer in
+ *       the documentation and/or other materials provided with the
+ *       distribution.
+ *     * Neither the name of Intel Corporation nor the names of its
+ *       contributors may be used to endorse or promote products derived
+ *       from this software without specific prior written permission.
+ *
+ *   THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ *   "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ *   LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+ *   A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+ *   OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+ *   SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+ *   LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+ *   DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+ *   THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ *   (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+ *   OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#ifndef _MAIN_H_
+#define _MAIN_H_
+
+#ifdef RTE_EXEC_ENV_BAREMETAL
+#define MAIN _main
+#else
+#define MAIN main
+#endif
+
+//#define DEBUG
+
+#ifdef DEBUG
+#define LOG_LEVEL RTE_LOG_DEBUG
+#define LOG_DEBUG(log_type, fmt, args...) do {	\
+	RTE_LOG(DEBUG, log_type, fmt, ##args);		\
+} while (0)
+#else
+#define LOG_LEVEL RTE_LOG_INFO
+#define LOG_DEBUG(log_type, fmt, args...) do{} while(0)
+#endif
+
+/* Macros for printing using RTE_LOG */
+#define RTE_LOGTYPE_VHOST_CONFIG RTE_LOGTYPE_USER1
+#define RTE_LOGTYPE_VHOST_DATA   RTE_LOGTYPE_USER2
+#define RTE_LOGTYPE_VHOST_PORT   RTE_LOGTYPE_USER3
+
+/*
+ * Device linked list structure for data path.
+ */
+struct virtio_net_data_ll
+{
+	struct virtio_net			*dev;	/* Pointer to device created by configuration core. */
+	struct virtio_net_data_ll	*next;  /* Pointer to next device in linked list. */
+};
+
+/*
+ * Structure containing data core specific information.
+ */
+struct lcore_ll_info
+{
+	struct virtio_net_data_ll	*ll_root_free; 		/* Pointer to head in free linked list. */
+	struct virtio_net_data_ll	*ll_root_used;		/* Pointer to head of used linked list. */
+	uint32_t 					device_num;			/* Number of devices on lcore. */
+	volatile uint8_t			dev_removal_flag;	/* Flag to synchronize device removal. */
+};
+
+struct lcore_info
+{
+	struct lcore_ll_info	*lcore_ll;	/* Pointer to data core specific lcore_ll_info struct */
+};
+
+int MAIN(int argc, char **argv);
+#endif /* _MAIN_H_ */
diff --git a/lib/librte_vhost/vhost-net-cdev.c b/lib/librte_vhost/vhost-net-cdev.c
new file mode 100644
index 0000000..8cf806a
--- /dev/null
+++ b/lib/librte_vhost/vhost-net-cdev.c
@@ -0,0 +1,367 @@
+/*-
+ *   BSD LICENSE
+ *
+ *   Copyright(c) 2010-2014 Intel Corporation. All rights reserved.
+ *   All rights reserved.
+ *
+ *   Redistribution and use in source and binary forms, with or without
+ *   modification, are permitted provided that the following conditions
+ *   are met:
+ *
+ *     * Redistributions of source code must retain the above copyright
+ *       notice, this list of conditions and the following disclaimer.
+ *     * Redistributions in binary form must reproduce the above copyright
+ *       notice, this list of conditions and the following disclaimer in
+ *       the documentation and/or other materials provided with the
+ *       distribution.
+ *     * Neither the name of Intel Corporation nor the names of its
+ *       contributors may be used to endorse or promote products derived
+ *       from this software without specific prior written permission.
+ *
+ *   THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ *   "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ *   LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+ *   A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+ *   OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+ *   SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+ *   LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+ *   DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+ *   THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ *   (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+ *   OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#include <errno.h>
+#include <fuse/cuse_lowlevel.h>
+#include <linux/limits.h>
+#include <linux/vhost.h>
+#include <stdint.h>
+#include <string.h>
+#include <unistd.h>
+
+#include <rte_ethdev.h>
+#include <rte_log.h>
+#include <rte_string_fns.h>
+
+#include "main.h"
+#include "vhost-net-cdev.h"
+
+#define FUSE_OPT_DUMMY 		"\0\0"
+#define FUSE_OPT_FORE 		"-f\0\0"
+#define FUSE_OPT_NOMULTI 	"-s\0\0"
+
+const uint32_t	default_major = 231;
+const uint32_t	default_minor = 1;
+const char		cuse_device_name[]	= "/dev/cuse";
+const char		default_cdev[] = "vhost-net";
+
+static struct fuse_session			*session;
+static struct vhost_net_device_ops	const *ops;
+
+/*
+ * Returns vhost_device_ctx from given fuse_req_t. The index is populated later when
+ * the device is added to the device linked list.
+ */
+static struct vhost_device_ctx
+fuse_req_to_vhost_ctx(fuse_req_t req, struct fuse_file_info *fi)
+{
+	struct vhost_device_ctx ctx;
+	struct fuse_ctx const *const req_ctx = fuse_req_ctx(req);
+
+	ctx.pid = req_ctx->pid;
+	ctx.fh = fi->fh;
+
+	return ctx;
+}
+
+/*
+ * When the device is created in QEMU it gets initialised here and added to the device linked list.
+ */
+static void
+vhost_net_open(fuse_req_t req, struct fuse_file_info *fi)
+{
+	struct vhost_device_ctx ctx = fuse_req_to_vhost_ctx(req, fi);
+	int err = 0;
+
+	err = ops->new_device(ctx);
+	if (err == -1) {
+		fuse_reply_err(req, EPERM);
+		return;
+	}
+
+	fi->fh = err;
+
+	RTE_LOG(INFO, VHOST_CONFIG, "(%"PRIu64") Device configuration started\n", fi->fh);
+	fuse_reply_open(req, fi);
+}
+
+/*
+ * When QEMU is shutdown or killed the device gets released.
+ */
+static void
+vhost_net_release(fuse_req_t req, struct fuse_file_info *fi)
+{
+	int err = 0;
+	struct vhost_device_ctx ctx = fuse_req_to_vhost_ctx(req, fi);
+
+	ops->destroy_device(ctx);
+	RTE_LOG(INFO, VHOST_CONFIG, "(%"PRIu64") Device released\n", ctx.fh);
+	fuse_reply_err(req, err);
+}
+
+/*
+ * Boilerplate code for CUSE IOCTL
+ * Implicit arguments: ctx, req, result.
+ */
+#define VHOST_IOCTL(func) do {								\
+	result = (func)(ctx);									\
+	fuse_reply_ioctl(req, result, NULL, 0);					\
+} while(0)													\
+
+/*
+ * Boilerplate IOCTL RETRY
+ * Implicit arguments: req.
+ */
+#define VHOST_IOCTL_RETRY(size_r, size_w) do {									\
+	struct iovec iov_r = { arg, (size_r) };										\
+	struct iovec iov_w = { arg, (size_w) };										\
+	fuse_reply_ioctl_retry(req, &iov_r, (size_r)?1:0, &iov_w, (size_w)?1:0);	\
+} while(0)																		\
+
+/*
+ * Boilerplate code for CUSE Read IOCTL
+ * Implicit arguments: ctx, req, result, in_bufsz, in_buf.
+ */
+#define VHOST_IOCTL_R(type, var, func) do {				\
+	if (!in_bufsz) {									\
+		VHOST_IOCTL_RETRY(sizeof(type), 0);				\
+	} else {											\
+		(var) = *(const type * ) in_buf;				\
+		result = func(ctx, &(var));						\
+		fuse_reply_ioctl(req, result, NULL, 0);			\
+	}													\
+} while(0)												\
+
+/*
+ *	Boilerplate code for CUSE Write IOCTL
+ * Implicit arguments: ctx, req, result, out_bufsz.
+ */
+#define	VHOST_IOCTL_W(type, var, func) do {						\
+	if (!out_bufsz) {											\
+		VHOST_IOCTL_RETRY(0, sizeof(type));						\
+	} else {													\
+		result = (func)(ctx, &(var));							\
+		fuse_reply_ioctl(req, result, &(var), sizeof(type));	\
+	}															\
+} while(0)														\
+
+/*
+ * Boilerplate code for CUSE Read/Write IOCTL
+ * Implicit arguments: ctx, req, result, in_bufsz, in_buf.
+ */
+#define VHOST_IOCTL_RW(type1, var1, type2, var2, func) do {			\
+	if (!in_bufsz) {												\
+		VHOST_IOCTL_RETRY(sizeof(type1), sizeof(type2));			\
+	} else {														\
+		(var1) = *(const type1* ) (in_buf);							\
+		result = (func)(ctx, (var1), &(var2));						\
+		fuse_reply_ioctl(req, result, &(var2), sizeof(type2));		\
+	}																\
+} while(0)															\
+
+/*
+ * The IOCTLs are handled using CUSE/FUSE in userspace. Depending on
+ * the type of IOCTL a buffer is requested to read or to write. This
+ * request is handled by FUSE and the buffer is then given to CUSE.
+ */
+static void
+vhost_net_ioctl(fuse_req_t req, int cmd, void *arg,
+		struct fuse_file_info *fi, __rte_unused unsigned flags,
+		const void *in_buf, size_t in_bufsz, size_t out_bufsz)
+{
+	struct vhost_device_ctx ctx = fuse_req_to_vhost_ctx(req, fi);
+	struct vhost_vring_file file;
+	struct vhost_vring_state state;
+	struct vhost_vring_addr addr;
+	uint64_t features;
+	uint32_t index;
+	int result = 0;
+
+	switch(cmd)
+	{
+		case VHOST_NET_SET_BACKEND:
+			LOG_DEBUG(VHOST_CONFIG, "(%"PRIu64") IOCTL: VHOST_NET_SET_BACKEND\n", ctx.fh);
+			VHOST_IOCTL_R(struct vhost_vring_file, file, ops->set_backend);
+			break;
+
+		case VHOST_GET_FEATURES:
+			LOG_DEBUG(VHOST_CONFIG, "(%"PRIu64") IOCTL: VHOST_GET_FEATURES\n", ctx.fh);
+			VHOST_IOCTL_W(uint64_t, features, ops->get_features);
+			break;
+
+		case VHOST_SET_FEATURES:
+			LOG_DEBUG(VHOST_CONFIG, "(%"PRIu64") IOCTL: VHOST_SET_FEATURES\n", ctx.fh);
+			VHOST_IOCTL_R(uint64_t, features, ops->set_features);
+			break;
+
+		case VHOST_RESET_OWNER:
+			LOG_DEBUG(VHOST_CONFIG, "(%"PRIu64") IOCTL: VHOST_RESET_OWNER\n", ctx.fh);
+			VHOST_IOCTL(ops->reset_owner);
+			break;
+
+		case VHOST_SET_OWNER:
+			LOG_DEBUG(VHOST_CONFIG, "(%"PRIu64") IOCTL: VHOST_SET_OWNER\n", ctx.fh);
+			VHOST_IOCTL(ops->set_owner);
+			break;
+
+		case VHOST_SET_MEM_TABLE:
+			LOG_DEBUG(VHOST_CONFIG, "(%"PRIu64") IOCTL: VHOST_SET_MEM_TABLE\n", ctx.fh);
+			static struct vhost_memory mem_temp;
+
+			switch(in_bufsz){
+				case 0:
+					VHOST_IOCTL_RETRY(sizeof(struct vhost_memory), 0);
+					break;
+
+				case sizeof(struct vhost_memory):
+					mem_temp = *(const struct vhost_memory *) in_buf;
+
+					if (mem_temp.nregions > 0) {
+						VHOST_IOCTL_RETRY(sizeof(struct vhost_memory) + (sizeof(struct vhost_memory_region) * mem_temp.nregions), 0);
+					} else {
+						result = -1;
+						fuse_reply_ioctl(req, result, NULL, 0);
+					}
+					break;
+
+				default:
+					result = ops->set_mem_table(ctx, in_buf, mem_temp.nregions);
+					if (result)
+						fuse_reply_err(req, EINVAL);
+					else
+						fuse_reply_ioctl(req, result, NULL, 0);
+
+			}
+
+			break;
+
+		case VHOST_SET_VRING_NUM:
+			LOG_DEBUG(VHOST_CONFIG, "(%"PRIu64") IOCTL: VHOST_SET_VRING_NUM\n", ctx.fh);
+			VHOST_IOCTL_R(struct vhost_vring_state, state, ops->set_vring_num);
+			break;
+
+		case VHOST_SET_VRING_BASE:
+			LOG_DEBUG(VHOST_CONFIG, "(%"PRIu64") IOCTL: VHOST_SET_VRING_BASE\n", ctx.fh);
+			VHOST_IOCTL_R(struct vhost_vring_state, state, ops->set_vring_base);
+			break;
+
+		case VHOST_GET_VRING_BASE:
+			LOG_DEBUG(VHOST_CONFIG, "(%"PRIu64") IOCTL: VHOST_GET_VRING_BASE\n", ctx.fh);
+			VHOST_IOCTL_RW(uint32_t, index, struct vhost_vring_state, state, ops->get_vring_base);
+			break;
+
+		case VHOST_SET_VRING_ADDR:
+			LOG_DEBUG(VHOST_CONFIG, "(%"PRIu64") IOCTL: VHOST_SET_VRING_ADDR\n", ctx.fh);
+			VHOST_IOCTL_R(struct vhost_vring_addr, addr, ops->set_vring_addr);
+			break;
+
+		case VHOST_SET_VRING_KICK:
+			LOG_DEBUG(VHOST_CONFIG, "(%"PRIu64") IOCTL: VHOST_SET_VRING_KICK\n", ctx.fh);
+			VHOST_IOCTL_R(struct vhost_vring_file, file, ops->set_vring_kick);
+			break;
+
+		case VHOST_SET_VRING_CALL:
+			LOG_DEBUG(VHOST_CONFIG, "(%"PRIu64") IOCTL: VHOST_SET_VRING_CALL\n", ctx.fh);
+			VHOST_IOCTL_R(struct vhost_vring_file, file, ops->set_vring_call);
+			break;
+
+		default:
+			RTE_LOG(ERR, VHOST_CONFIG, "(%"PRIu64") IOCTL: DOESN NOT EXIST\n", ctx.fh);
+			result = -1;
+			fuse_reply_ioctl(req, result, NULL, 0);
+	}
+
+	if (result < 0) {
+		LOG_DEBUG(VHOST_CONFIG, "(%"PRIu64") IOCTL: FAIL\n", ctx.fh);
+	} else {
+		LOG_DEBUG(VHOST_CONFIG, "(%"PRIu64") IOCTL: SUCCESS\n", ctx.fh);
+	}
+}
+
+/*
+ * Structure handling open, release and ioctl function pointers is populated.
+ */
+static const struct cuse_lowlevel_ops vhost_net_ops = {
+	.open		= vhost_net_open,
+	.release	= vhost_net_release,
+	.ioctl		= vhost_net_ioctl,
+};
+
+/*
+ * cuse_info is populated and used to register the cuse device. vhost_net_device_ops are
+ * also passed when the device is registered in main.c.
+ */
+int
+register_cuse_device(const char *base_name, int index, struct vhost_net_device_ops const * const pops)
+{
+	struct cuse_info cuse_info;
+	char device_name[PATH_MAX] = "";
+	char char_device_name[PATH_MAX] = "";
+	const char *device_argv[] = { device_name };
+
+	char fuse_opt_dummy[] = FUSE_OPT_DUMMY;
+	char fuse_opt_fore[] = FUSE_OPT_FORE;
+	char fuse_opt_nomulti[] = FUSE_OPT_NOMULTI;
+	char *fuse_argv[] = {fuse_opt_dummy, fuse_opt_fore, fuse_opt_nomulti};
+
+	if (access(cuse_device_name, R_OK | W_OK) < 0) {
+		RTE_LOG(ERR, VHOST_CONFIG, "Character device %s can't be accessed, maybe not exist\n", cuse_device_name);
+		return -1;
+	}
+
+	/*
+	 * The device name is created. This is passed to QEMU so that it can register
+	 * the device with our application. The index allows us to have multiple instances
+	 * of userspace vhost which we can then add devices to separately.
+	 */
+	if (strncmp(base_name, default_cdev, PATH_MAX)!=0) {
+		snprintf(device_name, PATH_MAX, "DEVNAME=%s-%d", base_name, index);
+		snprintf(char_device_name, PATH_MAX, "/dev/%s-%d", base_name, index);
+	} else {
+		snprintf(device_name, PATH_MAX, "DEVNAME=%s", base_name);
+		snprintf(char_device_name, PATH_MAX, "/dev/%s", base_name);
+	}
+
+	/* Check if device already exists. */
+	if (access(char_device_name, F_OK) != -1) {
+		RTE_LOG(ERR, VHOST_CONFIG, "Character device %s already exists\n", char_device_name);
+		return -1;
+	}
+
+	memset(&cuse_info, 0, sizeof(cuse_info));
+	cuse_info.dev_major = default_major;
+	cuse_info.dev_minor = default_minor + index;
+	cuse_info.dev_info_argc = 1;
+	cuse_info.dev_info_argv = device_argv;
+	cuse_info.flags = CUSE_UNRESTRICTED_IOCTL;
+
+	ops = pops;
+
+	session = cuse_lowlevel_setup(3, fuse_argv,
+				&cuse_info, &vhost_net_ops, 0, NULL);
+	if (session == NULL)
+		return -1;
+
+	return 0;
+}
+
+/*
+ * The CUSE session is launched allowing the application to receive open, release and ioctl calls.
+ */
+int
+start_cuse_session_loop(void)
+{
+	fuse_session_loop(session);
+
+	return 0;
+}
diff --git a/lib/librte_vhost/vhost-net-cdev.h b/lib/librte_vhost/vhost-net-cdev.h
new file mode 100644
index 0000000..575daa9
--- /dev/null
+++ b/lib/librte_vhost/vhost-net-cdev.h
@@ -0,0 +1,83 @@
+/*-
+ *   BSD LICENSE
+ *
+ *   Copyright(c) 2010-2014 Intel Corporation. All rights reserved.
+ *   All rights reserved.
+ *
+ *   Redistribution and use in source and binary forms, with or without
+ *   modification, are permitted provided that the following conditions
+ *   are met:
+ *
+ *     * Redistributions of source code must retain the above copyright
+ *       notice, this list of conditions and the following disclaimer.
+ *     * Redistributions in binary form must reproduce the above copyright
+ *       notice, this list of conditions and the following disclaimer in
+ *       the documentation and/or other materials provided with the
+ *       distribution.
+ *     * Neither the name of Intel Corporation nor the names of its
+ *       contributors may be used to endorse or promote products derived
+ *       from this software without specific prior written permission.
+ *
+ *   THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ *   "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ *   LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+ *   A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+ *   OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+ *   SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+ *   LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+ *   DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+ *   THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ *   (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+ *   OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#ifndef _VHOST_NET_CDEV_H_
+#define _VHOST_NET_CDEV_H_
+
+#include <linux/vhost.h>
+
+struct vhost_memory;
+struct vhost_vring_state;
+struct vhost_vring_addr;
+struct vhost_vring_file;
+
+/*
+ * Structure used to identify device context.
+ */
+struct vhost_device_ctx
+{
+	pid_t		pid;	/* PID of process calling the IOCTL. */
+	uint64_t 	fh;		/* Populated with fi->fh to track the device index. */
+};
+
+/*
+ * Structure contains function pointers to be defined in virtio-net.c. These
+ * functions are called in CUSE context and are used to configure devices.
+ */
+struct vhost_net_device_ops {
+	int (* new_device) 		(struct vhost_device_ctx);
+	void (* destroy_device) (struct vhost_device_ctx);
+
+	int (* get_features) 	(struct vhost_device_ctx, uint64_t *);
+	int (* set_features) 	(struct vhost_device_ctx, uint64_t *);
+
+	int (* set_mem_table) 	(struct vhost_device_ctx, const void *, uint32_t);
+
+	int (* set_vring_num) 	(struct vhost_device_ctx, struct vhost_vring_state *);
+	int (* set_vring_addr) 	(struct vhost_device_ctx, struct vhost_vring_addr *);
+	int (* set_vring_base) 	(struct vhost_device_ctx, struct vhost_vring_state *);
+	int (* get_vring_base) 	(struct vhost_device_ctx, uint32_t, struct vhost_vring_state *);
+
+	int (* set_vring_kick) 	(struct vhost_device_ctx, struct vhost_vring_file *);
+	int (* set_vring_call) 	(struct vhost_device_ctx, struct vhost_vring_file *);
+
+	int (* set_backend) 	(struct vhost_device_ctx, struct vhost_vring_file *);
+
+	int (* set_owner) 		(struct vhost_device_ctx);
+	int (* reset_owner) 	(struct vhost_device_ctx);
+};
+
+int register_cuse_device(const char *base_name, int index, struct vhost_net_device_ops const * const);
+int start_cuse_session_loop(void);
+
+#endif /* _VHOST_NET_CDEV_H_ */
diff --git a/lib/librte_vhost/virtio-net.c b/lib/librte_vhost/virtio-net.c
new file mode 100644
index 0000000..5e659c7
--- /dev/null
+++ b/lib/librte_vhost/virtio-net.c
@@ -0,0 +1,1165 @@
+/*-
+ *   BSD LICENSE
+ *
+ *   Copyright(c) 2010-2014 Intel Corporation. All rights reserved.
+ *   All rights reserved.
+ *
+ *   Redistribution and use in source and binary forms, with or without
+ *   modification, are permitted provided that the following conditions
+ *   are met:
+ *
+ *     * Redistributions of source code must retain the above copyright
+ *       notice, this list of conditions and the following disclaimer.
+ *     * Redistributions in binary form must reproduce the above copyright
+ *       notice, this list of conditions and the following disclaimer in
+ *       the documentation and/or other materials provided with the
+ *       distribution.
+ *     * Neither the name of Intel Corporation nor the names of its
+ *       contributors may be used to endorse or promote products derived
+ *       from this software without specific prior written permission.
+ *
+ *   THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ *   "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ *   LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+ *   A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+ *   OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+ *   SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+ *   LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+ *   DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+ *   THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ *   (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+ *   OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#include <dirent.h>
+#include <fuse/cuse_lowlevel.h>
+#include <linux/vhost.h>
+#include <linux/virtio_net.h>
+#include <stddef.h>
+#include <stdint.h>
+#include <stdlib.h>
+#include <sys/eventfd.h>
+#include <sys/ioctl.h>
+#include <sys/mman.h>
+#include <unistd.h>
+
+#include <rte_ethdev.h>
+#include <rte_log.h>
+#include <rte_string_fns.h>
+#include <rte_memory.h>
+
+#include "main.h"
+#include "virtio-net.h"
+#include "vhost-net-cdev.h"
+#include "eventfd_link/eventfd_link.h"
+
+const char eventfd_cdev[] = "/dev/eventfd-link";
+
+extern uint32_t num_devices;
+static uint32_t num_cur_devices = 0;
+
+/* device ops to add/remove device to data core. */
+static struct virtio_net_device_ops const * notify_ops;
+/* Root address of the linked list in the configuration core. */
+static struct virtio_net_config_ll			*ll_root = NULL;
+
+/* Features supported by this application. RX merge buffers are disabled by default. */
+uint64_t VHOST_FEATURES = (0ULL << VIRTIO_NET_F_MRG_RXBUF);
+
+/* Line size for reading maps file. */
+const uint32_t BUFSIZE = PATH_MAX;
+
+/* Size of prot char array in procmap. */
+#define PROT_SZ 5
+
+/* Number of elements in procmap struct. */
+#define PROCMAP_SZ 8
+
+/* Structure containing information gathered from maps file. */
+struct procmap
+{
+	uint64_t	va_start;			/* Start virtual address in file. */
+	uint64_t	len;				/* Size of file. */
+	uint64_t	pgoff;				/* Not used. */
+	uint32_t	maj;				/* Not used. */
+	uint32_t	min;				/* Not used. */
+	uint32_t	ino;				/* Not used. */
+	char		prot[PROT_SZ];		/* Not used. */
+	char		fname[PATH_MAX];	/* File name. */
+};
+
+/*
+ * Converts QEMU virtual address to Vhost virtual address. This function is used
+ * to convert the ring addresses to our address space.
+ */
+static uint64_t
+qva_to_vva(struct virtio_net *dev, uint64_t qemu_va)
+{
+	struct virtio_memory_regions *region;
+	uint64_t vhost_va = 0;
+	uint32_t regionidx = 0;
+
+	/* Find the region where the address lives. */
+	for (regionidx = 0; regionidx < dev->mem->nregions; regionidx++) {
+		region = &dev->mem->regions[regionidx];
+		if ((qemu_va >= region->userspace_address) &&
+				(qemu_va <= region->userspace_address +
+			 	region->memory_size)) {
+			vhost_va = dev->mem->mapped_address + qemu_va - dev->mem->base_address;
+			break;
+		}
+	}
+	return vhost_va;
+}
+
+/*
+ * Locate the file containing QEMU's memory space and map it to our address space.
+ */
+static int
+host_memory_map (struct virtio_net *dev, struct virtio_memory *mem, pid_t pid, uint64_t addr)
+{
+	struct dirent *dptr = NULL;
+	struct procmap procmap;
+	DIR *dp = NULL;
+	int fd;
+	int i;
+	char memfile[PATH_MAX];
+	char mapfile[PATH_MAX];
+	char procdir[PATH_MAX];
+	char resolved_path[PATH_MAX];
+	FILE		*fmap;
+	void		*map;
+	uint8_t 	found = 0;
+	char 		line[BUFSIZE];
+	char dlm[] = "-   :   ";
+	char *str, *sp, *in[PROCMAP_SZ];
+	char *end = NULL;
+
+	/* Path where mem files are located. */
+	snprintf (procdir, PATH_MAX, "/proc/%u/fd/", pid);
+	/* Maps file used to locate mem file. */
+	snprintf (mapfile, PATH_MAX, "/proc/%u/maps", pid);
+
+	fmap = fopen(mapfile, "r");
+	if (fmap == NULL) {
+		RTE_LOG(ERR, VHOST_CONFIG, "(%"PRIu64") Failed to open maps file for pid %d\n", dev->device_fh, pid);
+		return -1;
+	}
+
+	/* Read through maps file until we find out base_address. */
+	while (fgets(line, BUFSIZE, fmap) != 0) {
+		str = line;
+		errno = 0;
+		/* Split line in to fields. */
+		for (i = 0; i < PROCMAP_SZ; i++) {
+			if (((in[i] = strtok_r(str, &dlm[i], &sp)) == NULL) || (errno != 0)) {
+				fclose(fmap);
+				return -1;
+			}
+			str = NULL;
+		}
+
+		/* Convert/Copy each field as needed. */
+		procmap.va_start = strtoull(in[0], &end, 16);
+		if ((in[0] == '\0') || (end == NULL) || (*end != '\0') || (errno != 0)) {
+			fclose(fmap);
+			return -1;
+		}
+
+		procmap.len = strtoull(in[1], &end, 16);
+		if ((in[1] == '\0') || (end == NULL) || (*end != '\0') || (errno != 0)) {
+			fclose(fmap);
+			return -1;
+		}
+
+		procmap.pgoff = strtoull(in[3], &end, 16);
+		if ((in[3] == '\0') || (end == NULL) || (*end != '\0') || (errno != 0)) {
+			fclose(fmap);
+			return -1;
+		}
+
+		procmap.maj = strtoul(in[4], &end, 16);
+		if ((in[4] == '\0') || (end == NULL) || (*end != '\0') || (errno != 0)) {
+			fclose(fmap);
+			return -1;
+		}
+
+		procmap.min = strtoul(in[5], &end, 16);
+		if ((in[5] == '\0') || (end == NULL) || (*end != '\0') || (errno != 0)) {
+			fclose(fmap);
+			return -1;
+		}
+
+		procmap.ino = strtoul(in[6], &end, 16);
+		if ((in[6] == '\0') || (end == NULL) || (*end != '\0') || (errno != 0)) {
+			fclose(fmap);
+			return -1;
+		}
+
+		memcpy(&procmap.prot, in[2], PROT_SZ);
+		memcpy(&procmap.fname, in[7], PATH_MAX);
+
+		if (procmap.va_start == addr) {
+			procmap.len = procmap.len - procmap.va_start;
+			found = 1;
+			break;
+		}
+	}
+	fclose(fmap);
+
+	if (!found) {
+		RTE_LOG(ERR, VHOST_CONFIG, "(%"PRIu64") Failed to find memory file in pid %d maps file\n", dev->device_fh, pid);
+		return -1;
+	}
+
+	/* Find the guest memory file among the process fds. */
+	dp = opendir(procdir);
+	if (dp == NULL) {
+		RTE_LOG(ERR, VHOST_CONFIG, "(%"PRIu64") Cannot open pid %d process directory \n", dev->device_fh, pid);
+		return -1;
+
+	}
+
+	found = 0;
+
+	/* Read the fd directory contents. */
+	while (NULL != (dptr = readdir(dp))) {
+		snprintf (memfile, PATH_MAX, "/proc/%u/fd/%s", pid, dptr->d_name);
+	    realpath(memfile, resolved_path);
+		if (resolved_path == NULL) {
+			RTE_LOG(ERR, VHOST_CONFIG, "(%"PRIu64") Failed to resolve fd directory\n", dev->device_fh);
+			closedir(dp);
+			return -1;
+		}
+		if (strncmp(resolved_path, procmap.fname,
+			strnlen(procmap.fname, PATH_MAX)) == 0) {
+			found = 1;
+			break;
+		}
+	}
+
+	closedir(dp);
+
+	if (found == 0) {
+		RTE_LOG(ERR, VHOST_CONFIG, "(%"PRIu64") Failed to find memory file for pid %d\n", dev->device_fh, pid);
+		return -1;
+	}
+	/* Open the shared memory file and map the memory into this process. */
+	fd = open(memfile, O_RDWR);
+
+	if (fd == -1) {
+		RTE_LOG(ERR, VHOST_CONFIG, "(%"PRIu64") Failed to open %s for pid %d\n", dev->device_fh, memfile, pid);
+		return -1;
+	}
+
+	map = mmap(0, (size_t)procmap.len, PROT_READ|PROT_WRITE , MAP_POPULATE|MAP_SHARED, fd, 0);
+	close (fd);
+
+	if (map == MAP_FAILED) {
+		RTE_LOG(ERR, VHOST_CONFIG, "(%"PRIu64") Error mapping the file %s for pid %d\n",  dev->device_fh, memfile, pid);
+		return -1;
+	}
+
+	/* Store the memory address and size in the device data structure */
+	mem->mapped_address = (uint64_t)(uintptr_t)map;
+	mem->mapped_size = procmap.len;
+
+	LOG_DEBUG(VHOST_CONFIG, "(%"PRIu64") Mem File: %s->%s - Size: %llu - VA: %p\n", dev->device_fh,
+		memfile, resolved_path, (long long unsigned)mem->mapped_size, map);
+
+	return 0;
+}
+
+/*
+ * Retrieves an entry from the devices configuration linked list.
+ */
+static struct virtio_net_config_ll *
+get_config_ll_entry(struct vhost_device_ctx ctx)
+{
+	struct virtio_net_config_ll *ll_dev = ll_root;
+
+	/* Loop through linked list until the device_fh is found. */
+	while (ll_dev != NULL) {
+		if (ll_dev->dev.device_fh == ctx.fh)
+			return ll_dev;
+		ll_dev = ll_dev->next;
+	}
+
+	return NULL;
+}
+
+/*
+ * Searches the configuration core linked list and retrieves the device if it exists.
+ */
+static struct virtio_net *
+get_device(struct vhost_device_ctx ctx)
+{
+	struct virtio_net_config_ll *ll_dev;
+
+	ll_dev = get_config_ll_entry(ctx);
+
+	/* If a matching entry is found in the linked list, return the device in that entry. */
+	if (ll_dev) {
+		return &ll_dev->dev;
+	}
+
+	RTE_LOG(ERR, VHOST_CONFIG, "(%"PRIu64") Device not found in linked list.\n", ctx.fh);
+	return NULL;
+}
+
+/*
+ * Add entry containing a device to the device configuration linked list.
+ */
+static void
+add_config_ll_entry(struct virtio_net_config_ll *new_ll_dev)
+{
+	struct virtio_net_config_ll *ll_dev = ll_root;
+
+	/* If ll_dev == NULL then this is the first device so go to else */
+	if (ll_dev) {
+		/* If the 1st device_fh != 0 then we insert our device here. */
+		if (ll_dev->dev.device_fh != 0)	{
+			new_ll_dev->dev.device_fh = 0;
+			new_ll_dev->next = ll_dev;
+			ll_root = new_ll_dev;
+		} else {
+			/* Increment through the ll until we find un unused device_fh. Insert the device at that entry*/
+			while ((ll_dev->next != NULL) && (ll_dev->dev.device_fh == (ll_dev->next->dev.device_fh - 1)))
+				ll_dev = ll_dev->next;
+
+			new_ll_dev->dev.device_fh = ll_dev->dev.device_fh + 1;
+			new_ll_dev->next = ll_dev->next;
+			ll_dev->next = new_ll_dev;
+		}
+	} else {
+		ll_root = new_ll_dev;
+		ll_root->dev.device_fh = 0;
+	}
+
+}
+
+/*
+ * Unmap any memory, close any file descriptors and free any memory owned by a device.
+ */
+static void
+cleanup_device(struct virtio_net *dev)
+{
+	/* Unmap QEMU memory file if mapped. */
+	if (dev->mem) {
+		munmap((void*)(uintptr_t)dev->mem->mapped_address, (size_t)dev->mem->mapped_size);
+		if (dev->mem->regions_hpa)
+			free(dev->mem->regions_hpa);
+		free(dev->mem);
+	}
+
+	/* Close any event notifiers opened by device. */
+	if (dev->virtqueue[VIRTIO_RXQ]->callfd)
+		close((int)dev->virtqueue[VIRTIO_RXQ]->callfd);
+	if (dev->virtqueue[VIRTIO_RXQ]->kickfd)
+		close((int)dev->virtqueue[VIRTIO_RXQ]->kickfd);
+	if (dev->virtqueue[VIRTIO_TXQ]->callfd)
+		close((int)dev->virtqueue[VIRTIO_TXQ]->callfd);
+	if (dev->virtqueue[VIRTIO_TXQ]->kickfd)
+		close((int)dev->virtqueue[VIRTIO_TXQ]->kickfd);
+}
+
+/*
+ * Release virtqueues and device memory.
+ */
+static void
+free_device(struct virtio_net_config_ll *ll_dev)
+{
+	/* Free any malloc'd memory */
+	free(ll_dev->dev.virtqueue[VIRTIO_RXQ]);
+	free(ll_dev->dev.virtqueue[VIRTIO_TXQ]);
+	free(ll_dev);
+}
+/*
+ * Remove an entry from the device configuration linked list.
+ */
+static struct virtio_net_config_ll *
+rm_config_ll_entry(struct virtio_net_config_ll *ll_dev, struct virtio_net_config_ll *ll_dev_last)
+{
+	/* First remove the device and then clean it up. */
+	if (ll_dev == ll_root) {
+		ll_root = ll_dev->next;
+		cleanup_device(&ll_dev->dev);
+		free_device(ll_dev);
+		return ll_root;
+	} else {
+		if (likely(ll_dev_last != NULL)) {
+			ll_dev_last->next = ll_dev->next;
+			cleanup_device(&ll_dev->dev);
+			free_device(ll_dev);
+			return ll_dev_last->next;
+		} else {
+			cleanup_device(&ll_dev->dev);
+			free_device(ll_dev);
+			RTE_LOG(ERR, VHOST_CONFIG, "Remove entry from config_ll failed\n");
+			return NULL;
+		}
+	}
+}
+
+/*
+ *  Initialise all variables in device structure.
+ */
+static void
+init_device(struct virtio_net *dev)
+{
+	uint64_t vq_offset;
+
+	/* Virtqueues have already been malloced so we don't want to set them to NULL. */
+	vq_offset = offsetof(struct virtio_net, mem);
+
+	/* Set everything to 0. */
+	memset((void*)(uintptr_t)((uint64_t)(uintptr_t)dev + vq_offset), 0,
+		(sizeof(struct virtio_net) - (size_t)vq_offset));
+	memset(dev->virtqueue[VIRTIO_RXQ], 0, sizeof(struct vhost_virtqueue));
+	memset(dev->virtqueue[VIRTIO_TXQ], 0, sizeof(struct vhost_virtqueue));
+
+	/* Backends are set to -1 indicating an inactive device. */
+	dev->virtqueue[VIRTIO_RXQ]->backend = VIRTIO_DEV_STOPPED;
+	dev->virtqueue[VIRTIO_TXQ]->backend = VIRTIO_DEV_STOPPED;
+}
+
+/*
+ * Function is called from the CUSE open function. The device structure is
+ * initialised and a new entry is added to the device configuration linked
+ * list.
+ */
+static int
+new_device(struct vhost_device_ctx ctx)
+{
+	struct virtio_net_config_ll *new_ll_dev;
+	struct vhost_virtqueue *virtqueue_rx, *virtqueue_tx;
+
+	/*check the number of devices in the system*/
+	if (num_cur_devices == num_devices) {
+		RTE_LOG(ERR, VHOST_CONFIG, "() Max num devices (%u) exceeded\n", num_devices);
+		return -1;
+	}
+
+	/* Setup device and virtqueues. */
+	new_ll_dev = malloc(sizeof(struct virtio_net_config_ll));
+	if (new_ll_dev == NULL) {
+		RTE_LOG(ERR, VHOST_CONFIG, "(%"PRIu64") Failed to allocate memory for dev.\n", ctx.fh);
+		return -1;
+	}
+
+	virtqueue_rx = malloc(sizeof(struct vhost_virtqueue));
+	if (virtqueue_rx == NULL) {
+		free(new_ll_dev);
+		RTE_LOG(ERR, VHOST_CONFIG, "(%"PRIu64") Failed to allocate memory for virtqueue_rx.\n", ctx.fh);
+		return -1;
+	}
+
+	virtqueue_tx = malloc(sizeof(struct vhost_virtqueue));
+	if (virtqueue_tx == NULL) {
+		free(virtqueue_rx);
+		free(new_ll_dev);
+		RTE_LOG(ERR, VHOST_CONFIG, "(%"PRIu64") Failed to allocate memory for virtqueue_tx.\n", ctx.fh);
+		return -1;
+	}
+
+	new_ll_dev->dev.virtqueue[VIRTIO_RXQ] = virtqueue_rx;
+	new_ll_dev->dev.virtqueue[VIRTIO_TXQ] = virtqueue_tx;
+
+	/* Initialise device and virtqueues. */
+	init_device(&new_ll_dev->dev);
+
+	new_ll_dev->next = NULL;
+
+	/* Add entry to device configuration linked list. */
+	add_config_ll_entry(new_ll_dev);
+
+	/*increment the number of devices in the system*/
+	num_cur_devices++;
+
+	return new_ll_dev->dev.device_fh;
+}
+
+/*
+ * Function is called from the CUSE release function. This function will cleanup
+ * the device and remove it from device configuration linked list.
+ */
+static void
+destroy_device(struct vhost_device_ctx ctx)
+{
+	struct virtio_net_config_ll *ll_dev_cur_ctx, *ll_dev_last = NULL;
+	struct virtio_net_config_ll *ll_dev_cur = ll_root;
+
+	/* Find the linked list entry for the device to be removed. */
+	ll_dev_cur_ctx = get_config_ll_entry(ctx);
+	while (ll_dev_cur != NULL) {
+		/* If the device is found or a device that doesn't exist is found then it is removed. */
+		if (ll_dev_cur == ll_dev_cur_ctx) {
+			/*
+			 * If the device is running on a data core then call the function to remove it from
+			 * the data core.
+			 */
+			if ((ll_dev_cur->dev.flags & VIRTIO_DEV_RUNNING))
+				notify_ops->destroy_device(&(ll_dev_cur->dev));
+			ll_dev_cur = rm_config_ll_entry(ll_dev_cur, ll_dev_last);
+		} else {
+			ll_dev_last = ll_dev_cur;
+			ll_dev_cur = ll_dev_cur->next;
+		}
+	}
+
+	/*decrement the number of devices in the system*/
+	num_cur_devices--;
+}
+
+/*
+ * Called from CUSE IOCTL: VHOST_SET_OWNER
+ * This function just returns success at the moment unless the device hasn't been initialised.
+ */
+static int
+set_owner(struct vhost_device_ctx ctx)
+{
+	struct virtio_net *dev;
+
+	dev = get_device(ctx);
+	if (dev == NULL)
+		return -1;
+
+	return 0;
+}
+
+/*
+ * Called from CUSE IOCTL: VHOST_RESET_OWNER
+ */
+static int
+reset_owner(struct vhost_device_ctx ctx)
+{
+	struct virtio_net_config_ll *ll_dev;
+
+	ll_dev = get_config_ll_entry(ctx);
+
+	cleanup_device(&ll_dev->dev);
+	init_device(&ll_dev->dev);
+
+	return 0;
+}
+
+/*
+ * Called from CUSE IOCTL: VHOST_GET_FEATURES
+ * The features that we support are requested.
+ */
+static int
+get_features(struct vhost_device_ctx ctx, uint64_t *pu)
+{
+	struct virtio_net *dev;
+
+	dev = get_device(ctx);
+	if (dev == NULL)
+		return -1;
+
+	/* Send our supported features. */
+	*pu = VHOST_FEATURES;
+	return 0;
+}
+
+/*
+ * Called from CUSE IOCTL: VHOST_SET_FEATURES
+ * We receive the negotiated set of features supported by us and the virtio device.
+ */
+static int
+set_features(struct vhost_device_ctx ctx, uint64_t *pu)
+{
+	struct virtio_net *dev;
+
+	dev = get_device(ctx);
+	if (dev == NULL)
+		return -1;
+	if (*pu & ~VHOST_FEATURES)
+		return -1;
+
+	/* Store the negotiated feature list for the device. */
+	dev->features = *pu;
+
+	/* Set the vhost_hlen depending on if VIRTIO_NET_F_MRG_RXBUF is set. */
+	if (dev->features & (1 << VIRTIO_NET_F_MRG_RXBUF)) {
+		LOG_DEBUG(VHOST_CONFIG, "(%"PRIu64") Mergeable RX buffers enabled\n", dev->device_fh);
+		dev->virtqueue[VIRTIO_RXQ]->vhost_hlen = sizeof(struct virtio_net_hdr_mrg_rxbuf);
+		dev->virtqueue[VIRTIO_TXQ]->vhost_hlen = sizeof(struct virtio_net_hdr_mrg_rxbuf);
+	} else {
+		LOG_DEBUG(VHOST_CONFIG, "(%"PRIu64") Mergeable RX buffers disabled\n", dev->device_fh);
+		dev->virtqueue[VIRTIO_RXQ]->vhost_hlen = sizeof(struct virtio_net_hdr);
+		dev->virtqueue[VIRTIO_TXQ]->vhost_hlen = sizeof(struct virtio_net_hdr);
+	}
+	return 0;
+}
+
+/*
+ * Calculate the region count of physical continous regions for one particular
+ * region of whose vhost virtual address is continous. The particular region
+ * start from vva_start, with size of 'size' in argument.
+ */
+static uint32_t check_hpa_regions(uint64_t vva_start, uint64_t size)
+{
+	uint32_t i, nregions = 0, page_size = PAGE_SIZE;
+	uint64_t cur_phys_addr = 0, next_phys_addr = 0;
+	if (vva_start % page_size) {
+		LOG_DEBUG(VHOST_CONFIG,
+			"in check_countinous: vva start(%p) mod page_size(%d) "
+			"has remainder\n",
+			(void *)(uintptr_t)vva_start, page_size);
+		return 0;
+	}
+	if (size % page_size) {
+		LOG_DEBUG(VHOST_CONFIG,
+			"in check_countinous: "
+			"size((%"PRIu64")) mod page_size(%d) has remainder\n",
+			size, page_size);
+		return 0;
+	}
+	for (i = 0; i < size - page_size; i = i + page_size) {
+		cur_phys_addr
+			= rte_mem_virt2phy((void *)(uintptr_t)(vva_start + i));
+		next_phys_addr = rte_mem_virt2phy(
+			(void *)(uintptr_t)(vva_start + i + page_size));
+		if ((cur_phys_addr + page_size) != next_phys_addr) {
+			++nregions;
+			LOG_DEBUG(VHOST_CONFIG,
+				"in check_continuous: hva addr:(%p) is not "
+				"continuous with hva addr:(%p), diff:%d\n",
+				(void *)(uintptr_t)(vva_start + (uint64_t)i),
+				(void *)(uintptr_t)(vva_start + (uint64_t)i
+				+ page_size), page_size);
+			LOG_DEBUG(VHOST_CONFIG,
+				"in check_continuous: hpa addr:(%p) is not "
+				"continuous with hpa addr:(%p), "
+				"diff:(%"PRIu64")\n",
+				(void *)(uintptr_t)cur_phys_addr,
+				(void *)(uintptr_t)next_phys_addr,
+				(next_phys_addr-cur_phys_addr));
+		}
+	}
+	return nregions;
+}
+
+/*
+ * Divide each region whose vhost virtual address is continous into a few
+ * sub-regions, make sure the physical address within each sub-region are
+ * continous. And fill offset(to GPA) and size etc. information of each
+ * sub-region into regions_hpa.
+ */
+static uint32_t fill_hpa_memory_regions(void *memory)
+{
+	uint32_t regionidx, regionidx_hpa = 0, i, k, page_size = PAGE_SIZE;
+	uint64_t cur_phys_addr = 0, next_phys_addr = 0, vva_start;
+	struct virtio_memory *virtio_memory = (struct virtio_memory *)memory;
+	struct virtio_memory_regions_hpa *mem_region_hpa
+		= virtio_memory->regions_hpa;
+
+	if (mem_region_hpa == NULL)
+		return 0;
+
+	for (regionidx = 0; regionidx < virtio_memory->nregions; regionidx++) {
+		vva_start = virtio_memory->regions[regionidx].guest_phys_address
+			+ virtio_memory->regions[regionidx].address_offset;
+		mem_region_hpa[regionidx_hpa].guest_phys_address
+			= virtio_memory->regions[regionidx].guest_phys_address;
+		mem_region_hpa[regionidx_hpa].host_phys_addr_offset =
+			rte_mem_virt2phy((void *)(uintptr_t)(vva_start))
+			- mem_region_hpa[regionidx_hpa].guest_phys_address;
+		LOG_DEBUG(VHOST_CONFIG,
+			"in fill_hpa_regions: guest phys addr start[%d]:(%p)\n",
+			regionidx_hpa,
+			(void *)(uintptr_t)
+			(mem_region_hpa[regionidx_hpa].guest_phys_address));
+		LOG_DEBUG(VHOST_CONFIG,
+			"in fill_hpa_regions: host  phys addr start[%d]:(%p)\n",
+			regionidx_hpa,
+			(void *)(uintptr_t)
+			(mem_region_hpa[regionidx_hpa].host_phys_addr_offset));
+		for (i = 0, k = 0;
+			i < virtio_memory->regions[regionidx].memory_size
+				- page_size;
+			i += page_size) {
+			cur_phys_addr = rte_mem_virt2phy(
+					(void *)(uintptr_t)(vva_start + i));
+			next_phys_addr = rte_mem_virt2phy(
+					(void *)(uintptr_t)(vva_start
+					+ i + page_size));
+			if ((cur_phys_addr + page_size) != next_phys_addr) {
+				mem_region_hpa[regionidx_hpa].guest_phys_address_end =
+					mem_region_hpa[regionidx_hpa].guest_phys_address
+					+ k + page_size;
+				mem_region_hpa[regionidx_hpa].memory_size
+					= k + page_size;
+				LOG_DEBUG(VHOST_CONFIG, "in fill_hpa_regions: guest "
+					"phys addr end  [%d]:(%p)\n",
+					regionidx_hpa,
+					(void *)(uintptr_t)
+					(mem_region_hpa[regionidx_hpa].guest_phys_address_end));
+				LOG_DEBUG(VHOST_CONFIG,
+					"in fill_hpa_regions: guest phys addr "
+					"size [%d]:(%p)\n",
+					regionidx_hpa,
+					(void *)(uintptr_t)
+					(mem_region_hpa[regionidx_hpa].memory_size));
+				mem_region_hpa[regionidx_hpa + 1].guest_phys_address
+					= mem_region_hpa[regionidx_hpa].guest_phys_address_end;
+				++regionidx_hpa;
+				mem_region_hpa[regionidx_hpa].host_phys_addr_offset =
+					next_phys_addr
+					- mem_region_hpa[regionidx_hpa].guest_phys_address;
+				LOG_DEBUG(VHOST_CONFIG, "in fill_hpa_regions: guest"
+					" phys addr start[%d]:(%p)\n",
+					regionidx_hpa,
+					(void *)(uintptr_t)
+					(mem_region_hpa[regionidx_hpa].guest_phys_address));
+				LOG_DEBUG(VHOST_CONFIG,
+					"in fill_hpa_regions: host  phys addr "
+					"start[%d]:(%p)\n",
+					regionidx_hpa,
+					(void *)(uintptr_t)
+					(mem_region_hpa[regionidx_hpa].host_phys_addr_offset));
+				k = 0;
+			} else {
+				k += page_size;
+			}
+		}
+		mem_region_hpa[regionidx_hpa].guest_phys_address_end
+			= mem_region_hpa[regionidx_hpa].guest_phys_address
+			+ k + page_size;
+		mem_region_hpa[regionidx_hpa].memory_size = k + page_size;
+		LOG_DEBUG(VHOST_CONFIG, "in fill_hpa_regions: guest phys addr end  "
+			"[%d]:(%p)\n", regionidx_hpa,
+			(void *)(uintptr_t)
+			(mem_region_hpa[regionidx_hpa].guest_phys_address_end));
+		LOG_DEBUG(VHOST_CONFIG, "in fill_hpa_regions: guest phys addr size "
+			"[%d]:(%p)\n", regionidx_hpa,
+			(void *)(uintptr_t)
+			(mem_region_hpa[regionidx_hpa].memory_size));
+		++regionidx_hpa;
+	}
+	return regionidx_hpa;
+}
+
+/*
+ * Called from CUSE IOCTL: VHOST_SET_MEM_TABLE
+ * This function creates and populates the memory structure for the device. This includes
+ * storing offsets used to translate buffer addresses.
+ */
+static int
+set_mem_table(struct vhost_device_ctx ctx, const void *mem_regions_addr, uint32_t nregions)
+{
+	struct virtio_net *dev;
+	struct vhost_memory_region *mem_regions;
+	struct virtio_memory *mem;
+	uint64_t size = offsetof(struct vhost_memory, regions);
+	uint32_t regionidx, valid_regions;
+
+	dev = get_device(ctx);
+	if (dev == NULL)
+		return -1;
+
+	if (dev->mem) {
+		munmap((void*)(uintptr_t)dev->mem->mapped_address, (size_t)dev->mem->mapped_size);
+		free(dev->mem);
+	}
+
+	/* Malloc the memory structure depending on the number of regions. */
+	mem = calloc(1, sizeof(struct virtio_memory) + (sizeof(struct virtio_memory_regions) * nregions));
+	if (mem == NULL) {
+		RTE_LOG(ERR, VHOST_CONFIG, "(%"PRIu64") Failed to allocate memory for dev->mem.\n", dev->device_fh);
+		return -1;
+	}
+
+	mem->nregions = nregions;
+
+	mem_regions = (void*)(uintptr_t)((uint64_t)(uintptr_t)mem_regions_addr + size);
+
+	for (regionidx = 0; regionidx < mem->nregions; regionidx++) {
+		/* Populate the region structure for each region. */
+		mem->regions[regionidx].guest_phys_address = mem_regions[regionidx].guest_phys_addr;
+		mem->regions[regionidx].guest_phys_address_end = mem->regions[regionidx].guest_phys_address +
+			mem_regions[regionidx].memory_size;
+		mem->regions[regionidx].memory_size = mem_regions[regionidx].memory_size;
+		mem->regions[regionidx].userspace_address = mem_regions[regionidx].userspace_addr;
+
+		LOG_DEBUG(VHOST_CONFIG, "(%"PRIu64") REGION: %u - GPA: %p - QEMU VA: %p - SIZE (%"PRIu64")\n", dev->device_fh,
+				regionidx, (void*)(uintptr_t)mem->regions[regionidx].guest_phys_address,
+				(void*)(uintptr_t)mem->regions[regionidx].userspace_address,
+				mem->regions[regionidx].memory_size);
+
+		/*set the base address mapping*/
+		if (mem->regions[regionidx].guest_phys_address == 0x0) {
+			mem->base_address = mem->regions[regionidx].userspace_address;
+			/* Map VM memory file */
+			if (host_memory_map(dev, mem, ctx.pid, mem->base_address) != 0) {
+				free(mem);
+				return -1;
+			}
+		}
+	}
+
+	/* Check that we have a valid base address. */
+	if (mem->base_address == 0) {
+		RTE_LOG(ERR, VHOST_CONFIG, "(%"PRIu64") Failed to find base address of qemu memory file.\n", dev->device_fh);
+		free(mem);
+		return -1;
+	}
+
+	/* Check if all of our regions have valid mappings. Usually one does not exist in the QEMU memory file. */
+	valid_regions = mem->nregions;
+	for (regionidx = 0; regionidx < mem->nregions; regionidx++) {
+		if ((mem->regions[regionidx].userspace_address < mem->base_address) ||
+			(mem->regions[regionidx].userspace_address > (mem->base_address + mem->mapped_size)))
+				valid_regions--;
+	}
+
+	/* If a region does not have a valid mapping we rebuild our memory struct to contain only valid entries. */
+	if (valid_regions != mem->nregions) {
+		LOG_DEBUG(VHOST_CONFIG, "(%"PRIu64") Not all memory regions exist in the QEMU mem file. Re-populating mem structure\n",
+			dev->device_fh);
+
+		/* Re-populate the memory structure with only valid regions. Invalid regions are over-written with memmove. */
+		valid_regions = 0;
+
+		for (regionidx = mem->nregions; 0 != regionidx--;) {
+			if ((mem->regions[regionidx].userspace_address < mem->base_address) ||
+					(mem->regions[regionidx].userspace_address > (mem->base_address + mem->mapped_size))) {
+				memmove(&mem->regions[regionidx], &mem->regions[regionidx + 1],
+					sizeof(struct virtio_memory_regions) * valid_regions);
+			} else {
+				valid_regions++;
+			}
+		}
+	}
+	mem->nregions = valid_regions;
+	mem->nregions_hpa = mem->nregions;
+	dev->mem = mem;
+
+	/*
+	 * Calculate the address offset for each region. This offset is used to identify the vhost virtual address
+	 * corresponding to a QEMU guest physical address.
+	 */
+	for (regionidx = 0; regionidx < dev->mem->nregions; regionidx++) {
+		dev->mem->regions[regionidx].address_offset = dev->mem->regions[regionidx].userspace_address - dev->mem->base_address
+			+ dev->mem->mapped_address - dev->mem->regions[regionidx].guest_phys_address;
+
+		dev->mem->nregions_hpa
+			+= check_hpa_regions(
+				dev->mem->regions[regionidx].guest_phys_address
+				+ dev->mem->regions[regionidx].address_offset,
+				dev->mem->regions[regionidx].memory_size);
+	}
+	if (dev->mem->regions_hpa != NULL) {
+		free(dev->mem->regions_hpa);
+		dev->mem->regions_hpa = NULL;
+	}
+
+	dev->mem->regions_hpa = (struct virtio_memory_regions_hpa *) calloc(1,
+		(sizeof(struct virtio_memory_regions_hpa)
+		* dev->mem->nregions_hpa));
+	if (dev->mem->regions_hpa == NULL) {
+		RTE_LOG(ERR, VHOST_CONFIG,
+			"(%"PRIu64") Failed to allocate memory for "
+			"dev->mem->regions_hpa.\n", dev->device_fh);
+		return -1;
+	}
+	if (fill_hpa_memory_regions(
+		(void *)dev->mem) != dev->mem->nregions_hpa) {
+		RTE_LOG(ERR, VHOST_CONFIG,
+			"in set_mem_table: hpa memory regions number mismatch: "
+			"[%d]\n", dev->mem->nregions_hpa);
+		return -1;
+	}
+
+	return 0;
+}
+
+/*
+ * Called from CUSE IOCTL: VHOST_SET_VRING_NUM
+ * The virtio device sends us the size of the descriptor ring.
+ */
+static int
+set_vring_num(struct vhost_device_ctx ctx, struct vhost_vring_state *state)
+{
+	struct virtio_net *dev;
+
+	dev = get_device(ctx);
+	if (dev == NULL)
+		return -1;
+
+	/* State->index refers to the queue index. The TX queue is 1, RX queue is 0. */
+	dev->virtqueue[state->index]->size = state->num;
+
+	return 0;
+}
+
+/*
+ * Called from CUSE IOCTL: VHOST_SET_VRING_ADDR
+ * The virtio device sends us the desc, used and avail ring addresses. This function
+ * then converts these to our address space.
+ */
+static int
+set_vring_addr(struct vhost_device_ctx ctx, struct vhost_vring_addr *addr)
+{
+	struct virtio_net *dev;
+	struct vhost_virtqueue *vq;
+
+	dev = get_device(ctx);
+	if (dev == NULL)
+		return -1;
+
+	/* addr->index refers to the queue index. The TX queue is 1, RX queue is 0. */
+	vq = dev->virtqueue[addr->index];
+
+	/* The addresses are converted from QEMU virtual to Vhost virtual. */
+	vq->desc = (struct vring_desc*)(uintptr_t)qva_to_vva(dev, addr->desc_user_addr);
+	if (vq->desc == 0) {
+		RTE_LOG(ERR, VHOST_CONFIG, "(%"PRIu64") Failed to find descriptor ring address.\n", dev->device_fh);
+		return -1;
+	}
+
+	vq->avail = (struct vring_avail*)(uintptr_t)qva_to_vva(dev, addr->avail_user_addr);
+	if (vq->avail == 0) {
+		RTE_LOG(ERR, VHOST_CONFIG, "(%"PRIu64") Failed to find available ring address.\n", dev->device_fh);
+		return -1;
+	}
+
+	vq->used = (struct vring_used*)(uintptr_t)qva_to_vva(dev, addr->used_user_addr);
+	if (vq->used == 0) {
+		RTE_LOG(ERR, VHOST_CONFIG, "(%"PRIu64") Failed to find used ring address.\n", dev->device_fh);
+		return -1;
+	}
+
+	LOG_DEBUG(VHOST_CONFIG, "(%"PRIu64") mapped address desc: %p\n", dev->device_fh, vq->desc);
+	LOG_DEBUG(VHOST_CONFIG, "(%"PRIu64") mapped address avail: %p\n", dev->device_fh, vq->avail);
+	LOG_DEBUG(VHOST_CONFIG, "(%"PRIu64") mapped address used: %p\n", dev->device_fh, vq->used);
+
+	return 0;
+}
+
+/*
+ * Called from CUSE IOCTL: VHOST_SET_VRING_BASE
+ * The virtio device sends us the available ring last used index.
+ */
+static int
+set_vring_base(struct vhost_device_ctx ctx, struct vhost_vring_state *state)
+{
+	struct virtio_net *dev;
+
+	dev = get_device(ctx);
+	if (dev == NULL)
+		return -1;
+
+	/* State->index refers to the queue index. The TX queue is 1, RX queue is 0. */
+	dev->virtqueue[state->index]->last_used_idx = state->num;
+	dev->virtqueue[state->index]->last_used_idx_res = state->num;
+
+	return 0;
+}
+
+/*
+ * Called from CUSE IOCTL: VHOST_GET_VRING_BASE
+ * We send the virtio device our available ring last used index.
+ */
+static int
+get_vring_base(struct vhost_device_ctx ctx, uint32_t index, struct vhost_vring_state *state)
+{
+	struct virtio_net *dev;
+
+	dev = get_device(ctx);
+	if (dev == NULL)
+		return -1;
+
+	state->index = index;
+	/* State->index refers to the queue index. The TX queue is 1, RX queue is 0. */
+	state->num = dev->virtqueue[state->index]->last_used_idx;
+
+	return 0;
+}
+
+/*
+ * This function uses the eventfd_link kernel module to copy an eventfd file descriptor
+ * provided by QEMU in to our process space.
+ */
+static int
+eventfd_copy(struct virtio_net *dev, struct eventfd_copy *eventfd_copy)
+{
+	int eventfd_link, ret;
+
+	/* Open the character device to the kernel module. */
+	eventfd_link = open(eventfd_cdev, O_RDWR);
+	if (eventfd_link < 0) {
+		RTE_LOG(ERR, VHOST_CONFIG, "(%"PRIu64") eventfd_link module is not loaded\n",  dev->device_fh);
+		return -1;
+	}
+
+	/* Call the IOCTL to copy the eventfd. */
+	ret = ioctl(eventfd_link, EVENTFD_COPY, eventfd_copy);
+	close(eventfd_link);
+
+	if (ret < 0) {
+		RTE_LOG(ERR, VHOST_CONFIG, "(%"PRIu64") EVENTFD_COPY ioctl failed\n",  dev->device_fh);
+		return -1;
+	}
+
+
+	return 0;
+}
+
+/*
+ * Called from CUSE IOCTL: VHOST_SET_VRING_CALL
+ * The virtio device sends an eventfd to interrupt the guest. This fd gets copied in
+ * to our process space.
+ */
+static int
+set_vring_call(struct vhost_device_ctx ctx, struct vhost_vring_file *file)
+{
+	struct virtio_net *dev;
+	struct eventfd_copy	eventfd_kick;
+	struct vhost_virtqueue *vq;
+
+	dev = get_device(ctx);
+	if (dev == NULL)
+		return -1;
+
+	/* file->index refers to the queue index. The TX queue is 1, RX queue is 0. */
+	vq = dev->virtqueue[file->index];
+
+	if (vq->kickfd)
+		close((int)vq->kickfd);
+
+	/* Populate the eventfd_copy structure and call eventfd_copy. */
+	vq->kickfd = eventfd(0, EFD_NONBLOCK | EFD_CLOEXEC);
+	eventfd_kick.source_fd = vq->kickfd;
+	eventfd_kick.target_fd = file->fd;
+	eventfd_kick.target_pid = ctx.pid;
+
+	if (eventfd_copy(dev, &eventfd_kick))
+		return -1;
+
+	return 0;
+}
+
+/*
+ * Called from CUSE IOCTL: VHOST_SET_VRING_KICK
+ * The virtio device sends an eventfd that it can use to notify us. This fd gets copied in
+ * to our process space.
+ */
+static int
+set_vring_kick(struct vhost_device_ctx ctx, struct vhost_vring_file *file)
+{
+	struct virtio_net *dev;
+	struct eventfd_copy eventfd_call;
+	struct vhost_virtqueue *vq;
+
+	dev = get_device(ctx);
+	if (dev == NULL)
+		return -1;
+
+	/* file->index refers to the queue index. The TX queue is 1, RX queue is 0. */
+	vq = dev->virtqueue[file->index];
+
+	if (vq->callfd)
+		close((int)vq->callfd);
+
+	/* Populate the eventfd_copy structure and call eventfd_copy. */
+	vq->callfd = eventfd(0, EFD_NONBLOCK | EFD_CLOEXEC);
+	eventfd_call.source_fd = vq->callfd;
+	eventfd_call.target_fd = file->fd;
+	eventfd_call.target_pid = ctx.pid;
+
+	if (eventfd_copy(dev, &eventfd_call))
+        return -1;
+
+	return 0;
+}
+
+/*
+ * Called from CUSE IOCTL: VHOST_NET_SET_BACKEND
+ * To complete device initialisation when the virtio driver is loaded we are provided with a
+ * valid fd for a tap device (not used by us). If this happens then we can add the device to a
+ * data core. When the virtio driver is removed we get fd=-1. At that point we remove the device
+ * from the data core. The device will still exist in the device configuration linked list.
+ */
+static int
+set_backend(struct vhost_device_ctx ctx, struct vhost_vring_file *file)
+{
+	struct virtio_net *dev;
+
+	dev = get_device(ctx);
+	if (dev == NULL) {
+		return -1;
+	}
+
+	/* file->index refers to the queue index. The TX queue is 1, RX queue is 0. */
+	dev->virtqueue[file->index]->backend = file->fd;
+
+	/* If the device isn't already running and both backend fds are set we add the device. */
+	if (!(dev->flags & VIRTIO_DEV_RUNNING)) {
+		if (((int)dev->virtqueue[VIRTIO_TXQ]->backend != VIRTIO_DEV_STOPPED) &&
+			((int)dev->virtqueue[VIRTIO_RXQ]->backend != VIRTIO_DEV_STOPPED))
+			return notify_ops->new_device(dev);
+	/* Otherwise we remove it. */
+	} else
+		if (file->fd == VIRTIO_DEV_STOPPED) {
+			notify_ops->destroy_device(dev);
+		}
+	return 0;
+}
+
+/*
+ * Function pointers are set for the device operations to allow CUSE to call functions
+ * when an IOCTL, device_add or device_release is received.
+ */
+static const struct vhost_net_device_ops vhost_device_ops =
+{
+	.new_device = new_device,
+	.destroy_device = destroy_device,
+
+	.get_features = get_features,
+	.set_features = set_features,
+
+	.set_mem_table = set_mem_table,
+
+	.set_vring_num = set_vring_num,
+	.set_vring_addr = set_vring_addr,
+	.set_vring_base = set_vring_base,
+	.get_vring_base = get_vring_base,
+
+	.set_vring_kick = set_vring_kick,
+	.set_vring_call = set_vring_call,
+
+	.set_backend = set_backend,
+
+	.set_owner = set_owner,
+	.reset_owner = reset_owner,
+};
+
+/*
+ * Called by main to setup callbacks when registering CUSE device.
+ */
+struct vhost_net_device_ops const *
+get_virtio_net_callbacks(void)
+{
+	return &vhost_device_ops;
+}
+
+/*
+ * Register ops so that we can add/remove device to data core.
+ */
+int
+init_virtio_net(struct virtio_net_device_ops const * const ops)
+{
+	notify_ops = ops;
+
+	return 0;
+}
+
+/*
+ * Currently not used as we Ctrl+c to exit application.
+ */
+int
+deinit_virtio_net(void)
+{
+	return 0;
+}
diff --git a/lib/librte_vhost/virtio-net.h b/lib/librte_vhost/virtio-net.h
new file mode 100644
index 0000000..1a2f0dc
--- /dev/null
+++ b/lib/librte_vhost/virtio-net.h
@@ -0,0 +1,161 @@
+/*-
+ *   BSD LICENSE
+ *
+ *   Copyright(c) 2010-2014 Intel Corporation. All rights reserved.
+ *   All rights reserved.
+ *
+ *   Redistribution and use in source and binary forms, with or without
+ *   modification, are permitted provided that the following conditions
+ *   are met:
+ *
+ *     * Redistributions of source code must retain the above copyright
+ *       notice, this list of conditions and the following disclaimer.
+ *     * Redistributions in binary form must reproduce the above copyright
+ *       notice, this list of conditions and the following disclaimer in
+ *       the documentation and/or other materials provided with the
+ *       distribution.
+ *     * Neither the name of Intel Corporation nor the names of its
+ *       contributors may be used to endorse or promote products derived
+ *       from this software without specific prior written permission.
+ *
+ *   THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ *   "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ *   LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+ *   A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+ *   OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+ *   SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+ *   LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+ *   DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+ *   THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ *   (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+ *   OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#ifndef _VIRTIO_NET_H_
+#define _VIRTIO_NET_H_
+
+/* Used to indicate that the device is running on a data core */
+#define VIRTIO_DEV_RUNNING 1
+
+/* Backend value set by guest. */
+#define VIRTIO_DEV_STOPPED -1
+
+#define PAGE_SIZE   4096
+
+/* Enum for virtqueue management. */
+enum {VIRTIO_RXQ, VIRTIO_TXQ, VIRTIO_QNUM};
+
+#define BUF_VECTOR_MAX 256
+
+/*
+ * Structure contains buffer address, length and descriptor index
+ * from vring to do scatter RX.
+*/
+struct buf_vector {
+uint64_t buf_addr;
+uint32_t buf_len;
+uint32_t desc_idx;
+};
+
+/*
+ * Structure contains variables relevant to TX/RX virtqueues.
+ */
+struct vhost_virtqueue
+{
+	struct vring_desc	*desc;				/* Virtqueue descriptor ring. */
+	struct vring_avail	*avail;				/* Virtqueue available ring. */
+	struct vring_used	*used;				/* Virtqueue used ring. */
+	uint32_t			size;				/* Size of descriptor ring. */
+	uint32_t			backend;			/* Backend value to determine if device should started/stopped. */
+	uint16_t			vhost_hlen;			/* Vhost header length (varies depending on RX merge buffers. */
+	volatile uint16_t	last_used_idx;		/* Last index used on the available ring */
+	volatile uint16_t	last_used_idx_res;	/* Used for multiple devices reserving buffers. */
+	eventfd_t			callfd;				/* Currently unused as polling mode is enabled. */
+	eventfd_t			kickfd;				/* Used to notify the guest (trigger interrupt). */
+	/* Used for scatter RX. */
+	struct buf_vector	buf_vec[BUF_VECTOR_MAX];
+} __rte_cache_aligned;
+
+/*
+ * Device structure contains all configuration information relating to the device.
+ */
+struct virtio_net
+{
+	struct vhost_virtqueue	*virtqueue[VIRTIO_QNUM];	/* Contains all virtqueue information. */
+	struct virtio_memory 	*mem;						/* QEMU memory and memory region information. */
+	struct ether_addr 		mac_address;				/* Device MAC address (Obtained on first TX packet). */
+	uint64_t 				features;					/* Negotiated feature set. */
+	uint64_t 				device_fh;					/* device identifier. */
+	uint32_t 				vmdq_rx_q;					/* RX VMDQ queue number. */
+	uint32_t 				flags;						/* Device flags. Only used to check if device is running on data core. */
+	uint32_t 				vlan_tag;					/* Vlan tag for device. Currently set to device_id (0-63). */
+	uint16_t 				coreid;						/* Data core that the device is added to. */
+	volatile uint8_t 		ready;						/* A device is set as ready if the MAC address has been set. */
+	volatile uint8_t		remove;						/* Device is marked for removal from the data core. */
+} __rte_cache_aligned;
+
+/*
+ * Device linked list structure for configuration.
+ */
+struct virtio_net_config_ll
+{
+	struct virtio_net		dev;	/* Virtio device. */
+	struct virtio_net_config_ll	*next; /* Next entry on linked list. */
+};
+
+/*
+ * Information relating to memory regions including offsets to addresses in QEMUs memory file.
+ */
+struct virtio_memory_regions {
+	uint64_t	guest_phys_address;		/* Base guest physical address of region. */
+	uint64_t	guest_phys_address_end;	/* End guest physical address of region. */
+	uint64_t	memory_size;			/* Size of region. */
+	uint64_t	userspace_address;		/* Base userspace address of region. */
+	uint64_t	address_offset;			/* Offset of region for address translation. */
+};
+
+/*
+ * Information relating to memory regions including offsets to
+ * addresses in host physical space.
+ */
+struct virtio_memory_regions_hpa {
+	/* Base guest physical address of region. */
+	uint64_t	guest_phys_address;
+	/* End guest physical address of region. */
+	uint64_t	guest_phys_address_end;
+	/* Size of region. */
+	uint64_t	memory_size;
+	/* Offset of region for gpa to hpa translation. */
+	uint64_t	host_phys_addr_offset;
+};
+
+/*
+ * Memory structure includes region and mapping information.
+ */
+struct virtio_memory {
+	uint64_t			base_address;			/* Base QEMU userspace address of the memory file. */
+	uint64_t			mapped_address;			/* Mapped address of memory file base in our applications memory space. */
+	uint64_t			mapped_size;			/* Total size of memory file. */
+	uint32_t			nregions;				/* Number of memory regions. */
+	 /* Number of memory regions for gpa to hpa translation. */
+	uint32_t			nregions_hpa;
+	/* Memory region information for gpa to hpa translation. */
+	struct virtio_memory_regions_hpa  *regions_hpa;
+	/* Memory region information. */
+	struct virtio_memory_regions      regions[0];
+};
+
+/*
+ * Device operations to add/remove device.
+ */
+struct virtio_net_device_ops {
+	int (* new_device) 		(struct virtio_net *);	/* Add device. */
+	void (* destroy_device)	(volatile struct virtio_net *);	/* Remove device. */
+};
+
+int init_virtio_net(struct virtio_net_device_ops const * const);
+int deinit_virtio_net(void);
+
+struct vhost_net_device_ops const * get_virtio_net_callbacks(void);
+
+#endif /* _VIRTIO_NET_H_ */
-- 
1.8.1.4

^ permalink raw reply	[flat|nested] 23+ messages in thread

* [dpdk-dev] [PATCH v5 02/11] lib/librte_vhost: refactor vhost lib for subsequent transform
  2014-09-26  9:45 [dpdk-dev] [PATCH v5 00/11] user space vhost library and vhost example Huawei Xie
  2014-09-26  9:45 ` [dpdk-dev] [PATCH v5 01/11] lib/librte_vhost: move src files in vhost example to vhost lib directory Huawei Xie
@ 2014-09-26  9:45 ` Huawei Xie
  2014-09-29 19:55   ` Thomas Monjalon
  2014-09-26  9:45 ` [dpdk-dev] [PATCH v5 03/11] lib/librte_vhost: vhost lib transform Huawei Xie
                   ` (8 subsequent siblings)
  10 siblings, 1 reply; 23+ messages in thread
From: Huawei Xie @ 2014-09-26  9:45 UTC (permalink / raw)
  To: dev

This patch does simple split of the original vhost example source
files in vhost lib directory.
vhost rx/tx functions virtio_dev_rx/tx are copied from main.c to
new file vhost_rxtx.c and license header is added.
main.c and main.h are removed and will be copied to new vhost
example in subsequent patch.
virtio-net.h is renamed to rte_virtio_net.h as API header file.

Signed-off-by: Huawei Xie <huawei.xie@intel.com>
---
 lib/librte_vhost/main.c           | 3725 -------------------------------------
 lib/librte_vhost/main.h           |   86 -
 lib/librte_vhost/rte_virtio_net.h |  161 ++
 lib/librte_vhost/vhost_rxtx.c     |  281 +++
 lib/librte_vhost/virtio-net.h     |  161 --
 5 files changed, 442 insertions(+), 3972 deletions(-)
 delete mode 100644 lib/librte_vhost/main.c
 delete mode 100644 lib/librte_vhost/main.h
 create mode 100644 lib/librte_vhost/rte_virtio_net.h
 create mode 100644 lib/librte_vhost/vhost_rxtx.c
 delete mode 100644 lib/librte_vhost/virtio-net.h

diff --git a/lib/librte_vhost/main.c b/lib/librte_vhost/main.c
deleted file mode 100644
index 85ee8b8..0000000
--- a/lib/librte_vhost/main.c
+++ /dev/null
@@ -1,3725 +0,0 @@
-/*-
- *   BSD LICENSE
- *
- *   Copyright(c) 2010-2014 Intel Corporation. All rights reserved.
- *   All rights reserved.
- *
- *   Redistribution and use in source and binary forms, with or without
- *   modification, are permitted provided that the following conditions
- *   are met:
- *
- *     * Redistributions of source code must retain the above copyright
- *       notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above copyright
- *       notice, this list of conditions and the following disclaimer in
- *       the documentation and/or other materials provided with the
- *       distribution.
- *     * Neither the name of Intel Corporation nor the names of its
- *       contributors may be used to endorse or promote products derived
- *       from this software without specific prior written permission.
- *
- *   THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- *   "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- *   LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- *   A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- *   OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- *   SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- *   LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- *   DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- *   THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- *   (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- *   OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
- */
-
-#include <arpa/inet.h>
-#include <getopt.h>
-#include <linux/if_ether.h>
-#include <linux/if_vlan.h>
-#include <linux/virtio_net.h>
-#include <linux/virtio_ring.h>
-#include <signal.h>
-#include <stdint.h>
-#include <sys/eventfd.h>
-#include <sys/param.h>
-#include <unistd.h>
-
-#include <rte_atomic.h>
-#include <rte_cycles.h>
-#include <rte_ethdev.h>
-#include <rte_log.h>
-#include <rte_string_fns.h>
-#include <rte_malloc.h>
-
-#include "main.h"
-#include "virtio-net.h"
-#include "vhost-net-cdev.h"
-
-#define MAX_QUEUES 128
-
-/* the maximum number of external ports supported */
-#define MAX_SUP_PORTS 1
-
-/*
- * Calculate the number of buffers needed per port
- */
-#define NUM_MBUFS_PER_PORT ((MAX_QUEUES*RTE_TEST_RX_DESC_DEFAULT) +  		\
-							(num_switching_cores*MAX_PKT_BURST) +  			\
-							(num_switching_cores*RTE_TEST_TX_DESC_DEFAULT) +\
-							(num_switching_cores*MBUF_CACHE_SIZE))
-
-#define MBUF_CACHE_SIZE 128
-#define MBUF_SIZE (2048 + sizeof(struct rte_mbuf) + RTE_PKTMBUF_HEADROOM)
-
-/*
- * No frame data buffer allocated from host are required for zero copy
- * implementation, guest will allocate the frame data buffer, and vhost
- * directly use it.
- */
-#define VIRTIO_DESCRIPTOR_LEN_ZCP 1518
-#define MBUF_SIZE_ZCP (VIRTIO_DESCRIPTOR_LEN_ZCP + sizeof(struct rte_mbuf) \
-	+ RTE_PKTMBUF_HEADROOM)
-#define MBUF_CACHE_SIZE_ZCP 0
-
-/*
- * RX and TX Prefetch, Host, and Write-back threshold values should be
- * carefully set for optimal performance. Consult the network
- * controller's datasheet and supporting DPDK documentation for guidance
- * on how these parameters should be set.
- */
-#define RX_PTHRESH 8 /* Default values of RX prefetch threshold reg. */
-#define RX_HTHRESH 8 /* Default values of RX host threshold reg. */
-#define RX_WTHRESH 4 /* Default values of RX write-back threshold reg. */
-
-/*
- * These default values are optimized for use with the Intel(R) 82599 10 GbE
- * Controller and the DPDK ixgbe PMD. Consider using other values for other
- * network controllers and/or network drivers.
- */
-#define TX_PTHRESH 36 /* Default values of TX prefetch threshold reg. */
-#define TX_HTHRESH 0  /* Default values of TX host threshold reg. */
-#define TX_WTHRESH 0  /* Default values of TX write-back threshold reg. */
-
-#define MAX_PKT_BURST 32 		/* Max burst size for RX/TX */
-#define MAX_MRG_PKT_BURST 16 	/* Max burst for merge buffers. Set to 1 due to performance issue. */
-#define BURST_TX_DRAIN_US 100 	/* TX drain every ~100us */
-
-#define BURST_RX_WAIT_US 15 	/* Defines how long we wait between retries on RX */
-#define BURST_RX_RETRIES 4		/* Number of retries on RX. */
-
-#define JUMBO_FRAME_MAX_SIZE    0x2600
-
-/* State of virtio device. */
-#define DEVICE_MAC_LEARNING 0
-#define DEVICE_RX			1
-#define DEVICE_SAFE_REMOVE	2
-
-/* Config_core_flag status definitions. */
-#define REQUEST_DEV_REMOVAL 1
-#define ACK_DEV_REMOVAL 0
-
-/* Configurable number of RX/TX ring descriptors */
-#define RTE_TEST_RX_DESC_DEFAULT 1024
-#define RTE_TEST_TX_DESC_DEFAULT 512
-
-/*
- * Need refine these 2 macros for legacy and DPDK based front end:
- * Max vring avail descriptor/entries from guest - MAX_PKT_BURST
- * And then adjust power 2.
- */
-/*
- * For legacy front end, 128 descriptors,
- * half for virtio header, another half for mbuf.
- */
-#define RTE_TEST_RX_DESC_DEFAULT_ZCP 32   /* legacy: 32, DPDK virt FE: 128. */
-#define RTE_TEST_TX_DESC_DEFAULT_ZCP 64   /* legacy: 64, DPDK virt FE: 64.  */
-
-/* Get first 4 bytes in mbuf headroom. */
-#define MBUF_HEADROOM_UINT32(mbuf) (*(uint32_t *)((uint8_t *)(mbuf) \
-		+ sizeof(struct rte_mbuf)))
-
-/* true if x is a power of 2 */
-#define POWEROF2(x) ((((x)-1) & (x)) == 0)
-
-#define INVALID_PORT_ID 0xFF
-
-/* Max number of devices. Limited by vmdq. */
-#define MAX_DEVICES 64
-
-/* Size of buffers used for snprintfs. */
-#define MAX_PRINT_BUFF 6072
-
-/* Maximum character device basename size. */
-#define MAX_BASENAME_SZ 10
-
-/* Maximum long option length for option parsing. */
-#define MAX_LONG_OPT_SZ 64
-
-/* Used to compare MAC addresses. */
-#define MAC_ADDR_CMP 0xFFFFFFFFFFFFULL
-
-/* Number of descriptors per cacheline. */
-#define DESC_PER_CACHELINE (CACHE_LINE_SIZE / sizeof(struct vring_desc))
-
-/* mask of enabled ports */
-static uint32_t enabled_port_mask = 0;
-
-/*Number of switching cores enabled*/
-static uint32_t num_switching_cores = 0;
-
-/* number of devices/queues to support*/
-static uint32_t num_queues = 0;
-uint32_t num_devices = 0;
-
-/*
- * Enable zero copy, pkts buffer will directly dma to hw descriptor,
- * disabled on default.
- */
-static uint32_t zero_copy;
-
-/* number of descriptors to apply*/
-static uint32_t num_rx_descriptor = RTE_TEST_RX_DESC_DEFAULT_ZCP;
-static uint32_t num_tx_descriptor = RTE_TEST_TX_DESC_DEFAULT_ZCP;
-
-/* max ring descriptor, ixgbe, i40e, e1000 all are 4096. */
-#define MAX_RING_DESC 4096
-
-struct vpool {
-	struct rte_mempool *pool;
-	struct rte_ring *ring;
-	uint32_t buf_size;
-} vpool_array[MAX_QUEUES+MAX_QUEUES];
-
-/* Enable VM2VM communications. If this is disabled then the MAC address compare is skipped. */
-typedef enum {
-	VM2VM_DISABLED = 0,
-	VM2VM_SOFTWARE = 1,
-	VM2VM_HARDWARE = 2,
-	VM2VM_LAST
-} vm2vm_type;
-static vm2vm_type vm2vm_mode = VM2VM_SOFTWARE;
-
-/* The type of host physical address translated from guest physical address. */
-typedef enum {
-	PHYS_ADDR_CONTINUOUS = 0,
-	PHYS_ADDR_CROSS_SUBREG = 1,
-	PHYS_ADDR_INVALID = 2,
-	PHYS_ADDR_LAST
-} hpa_type;
-
-/* Enable stats. */
-static uint32_t enable_stats = 0;
-/* Enable retries on RX. */
-static uint32_t enable_retry = 1;
-/* Specify timeout (in useconds) between retries on RX. */
-static uint32_t burst_rx_delay_time = BURST_RX_WAIT_US;
-/* Specify the number of retries on RX. */
-static uint32_t burst_rx_retry_num = BURST_RX_RETRIES;
-
-/* Character device basename. Can be set by user. */
-static char dev_basename[MAX_BASENAME_SZ] = "vhost-net";
-
-/* Charater device index. Can be set by user. */
-static uint32_t dev_index = 0;
-
-/* This can be set by the user so it is made available here. */
-extern uint64_t VHOST_FEATURES;
-
-/* Default configuration for rx and tx thresholds etc. */
-static struct rte_eth_rxconf rx_conf_default = {
-	.rx_thresh = {
-		.pthresh = RX_PTHRESH,
-		.hthresh = RX_HTHRESH,
-		.wthresh = RX_WTHRESH,
-	},
-	.rx_drop_en = 1,
-};
-
-/*
- * These default values are optimized for use with the Intel(R) 82599 10 GbE
- * Controller and the DPDK ixgbe/igb PMD. Consider using other values for other
- * network controllers and/or network drivers.
- */
-static struct rte_eth_txconf tx_conf_default = {
-	.tx_thresh = {
-		.pthresh = TX_PTHRESH,
-		.hthresh = TX_HTHRESH,
-		.wthresh = TX_WTHRESH,
-	},
-	.tx_free_thresh = 0, /* Use PMD default values */
-	.tx_rs_thresh = 0, /* Use PMD default values */
-};
-
-/* empty vmdq configuration structure. Filled in programatically */
-static struct rte_eth_conf vmdq_conf_default = {
-	.rxmode = {
-		.mq_mode        = ETH_MQ_RX_VMDQ_ONLY,
-		.split_hdr_size = 0,
-		.header_split   = 0, /**< Header Split disabled */
-		.hw_ip_checksum = 0, /**< IP checksum offload disabled */
-		.hw_vlan_filter = 0, /**< VLAN filtering disabled */
-		/*
-		 * It is necessary for 1G NIC such as I350,
-		 * this fixes bug of ipv4 forwarding in guest can't
-		 * forward pakets from one virtio dev to another virtio dev.
-		 */
-		.hw_vlan_strip  = 1, /**< VLAN strip enabled. */
-		.jumbo_frame    = 0, /**< Jumbo Frame Support disabled */
-		.hw_strip_crc   = 0, /**< CRC stripped by hardware */
-	},
-
-	.txmode = {
-		.mq_mode = ETH_MQ_TX_NONE,
-	},
-	.rx_adv_conf = {
-		/*
-		 * should be overridden separately in code with
-		 * appropriate values
-		 */
-		.vmdq_rx_conf = {
-			.nb_queue_pools = ETH_8_POOLS,
-			.enable_default_pool = 0,
-			.default_pool = 0,
-			.nb_pool_maps = 0,
-			.pool_map = {{0, 0},},
-		},
-	},
-};
-
-static unsigned lcore_ids[RTE_MAX_LCORE];
-static uint8_t ports[RTE_MAX_ETHPORTS];
-static unsigned num_ports = 0; /**< The number of ports specified in command line */
-
-static const uint16_t external_pkt_default_vlan_tag = 2000;
-const uint16_t vlan_tags[] = {
-	1000, 1001, 1002, 1003, 1004, 1005, 1006, 1007,
-	1008, 1009, 1010, 1011,	1012, 1013, 1014, 1015,
-	1016, 1017, 1018, 1019, 1020, 1021, 1022, 1023,
-	1024, 1025, 1026, 1027, 1028, 1029, 1030, 1031,
-	1032, 1033, 1034, 1035, 1036, 1037, 1038, 1039,
-	1040, 1041, 1042, 1043, 1044, 1045, 1046, 1047,
-	1048, 1049, 1050, 1051, 1052, 1053, 1054, 1055,
-	1056, 1057, 1058, 1059, 1060, 1061, 1062, 1063,
-};
-
-/* ethernet addresses of ports */
-static struct ether_addr vmdq_ports_eth_addr[RTE_MAX_ETHPORTS];
-
-/* heads for the main used and free linked lists for the data path. */
-static struct virtio_net_data_ll *ll_root_used = NULL;
-static struct virtio_net_data_ll *ll_root_free = NULL;
-
-/* Array of data core structures containing information on individual core linked lists. */
-static struct lcore_info lcore_info[RTE_MAX_LCORE];
-
-/* Used for queueing bursts of TX packets. */
-struct mbuf_table {
-	unsigned len;
-	unsigned txq_id;
-	struct rte_mbuf *m_table[MAX_PKT_BURST];
-};
-
-/* TX queue for each data core. */
-struct mbuf_table lcore_tx_queue[RTE_MAX_LCORE];
-
-/* TX queue fori each virtio device for zero copy. */
-struct mbuf_table tx_queue_zcp[MAX_QUEUES];
-
-/* Vlan header struct used to insert vlan tags on TX. */
-struct vlan_ethhdr {
-	unsigned char   h_dest[ETH_ALEN];
-	unsigned char   h_source[ETH_ALEN];
-	__be16          h_vlan_proto;
-	__be16          h_vlan_TCI;
-	__be16          h_vlan_encapsulated_proto;
-};
-
-/* IPv4 Header */
-struct ipv4_hdr {
-	uint8_t  version_ihl;		/**< version and header length */
-	uint8_t  type_of_service;	/**< type of service */
-	uint16_t total_length;		/**< length of packet */
-	uint16_t packet_id;		/**< packet ID */
-	uint16_t fragment_offset;	/**< fragmentation offset */
-	uint8_t  time_to_live;		/**< time to live */
-	uint8_t  next_proto_id;		/**< protocol ID */
-	uint16_t hdr_checksum;		/**< header checksum */
-	uint32_t src_addr;		/**< source address */
-	uint32_t dst_addr;		/**< destination address */
-} __attribute__((__packed__));
-
-/* Header lengths. */
-#define VLAN_HLEN       4
-#define VLAN_ETH_HLEN   18
-
-/* Per-device statistics struct */
-struct device_statistics {
-	uint64_t tx_total;
-	rte_atomic64_t rx_total_atomic;
-	uint64_t rx_total;
-	uint64_t tx;
-	rte_atomic64_t rx_atomic;
-	uint64_t rx;
-} __rte_cache_aligned;
-struct device_statistics dev_statistics[MAX_DEVICES];
-
-/*
- * Builds up the correct configuration for VMDQ VLAN pool map
- * according to the pool & queue limits.
- */
-static inline int
-get_eth_conf(struct rte_eth_conf *eth_conf, uint32_t num_devices)
-{
-	struct rte_eth_vmdq_rx_conf conf;
-	unsigned i;
-
-	memset(&conf, 0, sizeof(conf));
-	conf.nb_queue_pools = (enum rte_eth_nb_pools)num_devices;
-	conf.nb_pool_maps = num_devices;
-	conf.enable_loop_back =
-		vmdq_conf_default.rx_adv_conf.vmdq_rx_conf.enable_loop_back;
-
-	for (i = 0; i < conf.nb_pool_maps; i++) {
-		conf.pool_map[i].vlan_id = vlan_tags[ i ];
-		conf.pool_map[i].pools = (1UL << i);
-	}
-
-	(void)(rte_memcpy(eth_conf, &vmdq_conf_default, sizeof(*eth_conf)));
-	(void)(rte_memcpy(&eth_conf->rx_adv_conf.vmdq_rx_conf, &conf,
-		   sizeof(eth_conf->rx_adv_conf.vmdq_rx_conf)));
-	return 0;
-}
-
-/*
- * Validate the device number according to the max pool number gotten form
- * dev_info. If the device number is invalid, give the error message and
- * return -1. Each device must have its own pool.
- */
-static inline int
-validate_num_devices(uint32_t max_nb_devices)
-{
-	if (num_devices > max_nb_devices) {
-		RTE_LOG(ERR, VHOST_PORT, "invalid number of devices\n");
-		return -1;
-	}
-	return 0;
-}
-
-/*
- * Initialises a given port using global settings and with the rx buffers
- * coming from the mbuf_pool passed as parameter
- */
-static inline int
-port_init(uint8_t port)
-{
-	struct rte_eth_dev_info dev_info;
-	struct rte_eth_conf port_conf;
-	uint16_t rx_rings, tx_rings;
-	uint16_t rx_ring_size, tx_ring_size;
-	int retval;
-	uint16_t q;
-
-	/* The max pool number from dev_info will be used to validate the pool number specified in cmd line */
-	rte_eth_dev_info_get (port, &dev_info);
-
-	/*configure the number of supported virtio devices based on VMDQ limits */
-	num_devices = dev_info.max_vmdq_pools;
-	num_queues = dev_info.max_rx_queues;
-
-	if (zero_copy) {
-		rx_ring_size = num_rx_descriptor;
-		tx_ring_size = num_tx_descriptor;
-		tx_rings = dev_info.max_tx_queues;
-	} else {
-		rx_ring_size = RTE_TEST_RX_DESC_DEFAULT;
-		tx_ring_size = RTE_TEST_TX_DESC_DEFAULT;
-		tx_rings = (uint16_t)rte_lcore_count();
-	}
-
-	retval = validate_num_devices(MAX_DEVICES);
-	if (retval < 0)
-		return retval;
-
-	/* Get port configuration. */
-	retval = get_eth_conf(&port_conf, num_devices);
-	if (retval < 0)
-		return retval;
-
-	if (port >= rte_eth_dev_count()) return -1;
-
-	rx_rings = (uint16_t)num_queues,
-	/* Configure ethernet device. */
-	retval = rte_eth_dev_configure(port, rx_rings, tx_rings, &port_conf);
-	if (retval != 0)
-		return retval;
-
-	/* Setup the queues. */
-	for (q = 0; q < rx_rings; q ++) {
-		retval = rte_eth_rx_queue_setup(port, q, rx_ring_size,
-						rte_eth_dev_socket_id(port), &rx_conf_default,
-						vpool_array[q].pool);
-		if (retval < 0)
-			return retval;
-	}
-	for (q = 0; q < tx_rings; q ++) {
-		retval = rte_eth_tx_queue_setup(port, q, tx_ring_size,
-						rte_eth_dev_socket_id(port), &tx_conf_default);
-		if (retval < 0)
-			return retval;
-	}
-
-	/* Start the device. */
-	retval  = rte_eth_dev_start(port);
-	if (retval < 0) {
-		RTE_LOG(ERR, VHOST_DATA, "Failed to start the device.\n");
-		return retval;
-	}
-
-	rte_eth_macaddr_get(port, &vmdq_ports_eth_addr[port]);
-	RTE_LOG(INFO, VHOST_PORT, "Max virtio devices supported: %u\n", num_devices);
-	RTE_LOG(INFO, VHOST_PORT, "Port %u MAC: %02"PRIx8" %02"PRIx8" %02"PRIx8
-			" %02"PRIx8" %02"PRIx8" %02"PRIx8"\n",
-			(unsigned)port,
-			vmdq_ports_eth_addr[port].addr_bytes[0],
-			vmdq_ports_eth_addr[port].addr_bytes[1],
-			vmdq_ports_eth_addr[port].addr_bytes[2],
-			vmdq_ports_eth_addr[port].addr_bytes[3],
-			vmdq_ports_eth_addr[port].addr_bytes[4],
-			vmdq_ports_eth_addr[port].addr_bytes[5]);
-
-	return 0;
-}
-
-/*
- * Set character device basename.
- */
-static int
-us_vhost_parse_basename(const char *q_arg)
-{
-	/* parse number string */
-
-	if (strnlen(q_arg, MAX_BASENAME_SZ) > MAX_BASENAME_SZ)
-		return -1;
-	else
-		snprintf((char*)&dev_basename, MAX_BASENAME_SZ, "%s", q_arg);
-
-	return 0;
-}
-
-/*
- * Parse the portmask provided at run time.
- */
-static int
-parse_portmask(const char *portmask)
-{
-	char *end = NULL;
-	unsigned long pm;
-
-	errno = 0;
-
-	/* parse hexadecimal string */
-	pm = strtoul(portmask, &end, 16);
-	if ((portmask[0] == '\0') || (end == NULL) || (*end != '\0') || (errno != 0))
-		return -1;
-
-	if (pm == 0)
-		return -1;
-
-	return pm;
-
-}
-
-/*
- * Parse num options at run time.
- */
-static int
-parse_num_opt(const char *q_arg, uint32_t max_valid_value)
-{
-	char *end = NULL;
-	unsigned long num;
-
-	errno = 0;
-
-	/* parse unsigned int string */
-	num = strtoul(q_arg, &end, 10);
-	if ((q_arg[0] == '\0') || (end == NULL) || (*end != '\0') || (errno != 0))
-		return -1;
-
-	if (num > max_valid_value)
-		return -1;
-
-	return num;
-
-}
-
-/*
- * Display usage
- */
-static void
-us_vhost_usage(const char *prgname)
-{
-	RTE_LOG(INFO, VHOST_CONFIG, "%s [EAL options] -- -p PORTMASK\n"
-	"		--vm2vm [0|1|2]\n"
-	"		--rx_retry [0|1] --mergeable [0|1] --stats [0-N]\n"
-	"		--dev-basename <name> --dev-index [0-N]\n"
-	"		--nb-devices ND\n"
-	"		-p PORTMASK: Set mask for ports to be used by application\n"
-	"		--vm2vm [0|1|2]: disable/software(default)/hardware vm2vm comms\n"
-	"		--rx-retry [0|1]: disable/enable(default) retries on rx. Enable retry if destintation queue is full\n"
-	"		--rx-retry-delay [0-N]: timeout(in usecond) between retries on RX. This makes effect only if retries on rx enabled\n"
-	"		--rx-retry-num [0-N]: the number of retries on rx. This makes effect only if retries on rx enabled\n"
-	"		--mergeable [0|1]: disable(default)/enable RX mergeable buffers\n"
-	"		--stats [0-N]: 0: Disable stats, N: Time in seconds to print stats\n"
-	"		--dev-basename: The basename to be used for the character device.\n"
-	"		--dev-index [0-N]: Defaults to zero if not used. Index is appended to basename.\n"
-	"		--zero-copy [0|1]: disable(default)/enable rx/tx "
-			"zero copy\n"
-	"		--rx-desc-num [0-N]: the number of descriptors on rx, "
-			"used only when zero copy is enabled.\n"
-	"		--tx-desc-num [0-N]: the number of descriptors on tx, "
-			"used only when zero copy is enabled.\n",
-	       prgname);
-}
-
-/*
- * Parse the arguments given in the command line of the application.
- */
-static int
-us_vhost_parse_args(int argc, char **argv)
-{
-	int opt, ret;
-	int option_index;
-	unsigned i;
-	const char *prgname = argv[0];
-	static struct option long_option[] = {
-		{"vm2vm", required_argument, NULL, 0},
-		{"rx-retry", required_argument, NULL, 0},
-		{"rx-retry-delay", required_argument, NULL, 0},
-		{"rx-retry-num", required_argument, NULL, 0},
-		{"mergeable", required_argument, NULL, 0},
-		{"stats", required_argument, NULL, 0},
-		{"dev-basename", required_argument, NULL, 0},
-		{"dev-index", required_argument, NULL, 0},
-		{"zero-copy", required_argument, NULL, 0},
-		{"rx-desc-num", required_argument, NULL, 0},
-		{"tx-desc-num", required_argument, NULL, 0},
-		{NULL, 0, 0, 0},
-	};
-
-	/* Parse command line */
-	while ((opt = getopt_long(argc, argv, "p:",long_option, &option_index)) != EOF) {
-		switch (opt) {
-		/* Portmask */
-		case 'p':
-			enabled_port_mask = parse_portmask(optarg);
-			if (enabled_port_mask == 0) {
-				RTE_LOG(INFO, VHOST_CONFIG, "Invalid portmask\n");
-				us_vhost_usage(prgname);
-				return -1;
-			}
-			break;
-
-		case 0:
-			/* Enable/disable vm2vm comms. */
-			if (!strncmp(long_option[option_index].name, "vm2vm",
-				MAX_LONG_OPT_SZ)) {
-				ret = parse_num_opt(optarg, (VM2VM_LAST - 1));
-				if (ret == -1) {
-					RTE_LOG(INFO, VHOST_CONFIG,
-						"Invalid argument for "
-						"vm2vm [0|1|2]\n");
-					us_vhost_usage(prgname);
-					return -1;
-				} else {
-					vm2vm_mode = (vm2vm_type)ret;
-				}
-			}
-
-			/* Enable/disable retries on RX. */
-			if (!strncmp(long_option[option_index].name, "rx-retry", MAX_LONG_OPT_SZ)) {
-				ret = parse_num_opt(optarg, 1);
-				if (ret == -1) {
-					RTE_LOG(INFO, VHOST_CONFIG, "Invalid argument for rx-retry [0|1]\n");
-					us_vhost_usage(prgname);
-					return -1;
-				} else {
-					enable_retry = ret;
-				}
-			}
-
-			/* Specify the retries delay time (in useconds) on RX. */
-			if (!strncmp(long_option[option_index].name, "rx-retry-delay", MAX_LONG_OPT_SZ)) {
-				ret = parse_num_opt(optarg, INT32_MAX);
-				if (ret == -1) {
-					RTE_LOG(INFO, VHOST_CONFIG, "Invalid argument for rx-retry-delay [0-N]\n");
-					us_vhost_usage(prgname);
-					return -1;
-				} else {
-					burst_rx_delay_time = ret;
-				}
-			}
-
-			/* Specify the retries number on RX. */
-			if (!strncmp(long_option[option_index].name, "rx-retry-num", MAX_LONG_OPT_SZ)) {
-				ret = parse_num_opt(optarg, INT32_MAX);
-				if (ret == -1) {
-					RTE_LOG(INFO, VHOST_CONFIG, "Invalid argument for rx-retry-num [0-N]\n");
-					us_vhost_usage(prgname);
-					return -1;
-				} else {
-					burst_rx_retry_num = ret;
-				}
-			}
-
-			/* Enable/disable RX mergeable buffers. */
-			if (!strncmp(long_option[option_index].name, "mergeable", MAX_LONG_OPT_SZ)) {
-				ret = parse_num_opt(optarg, 1);
-				if (ret == -1) {
-					RTE_LOG(INFO, VHOST_CONFIG, "Invalid argument for mergeable [0|1]\n");
-					us_vhost_usage(prgname);
-					return -1;
-				} else {
-					if (ret) {
-						vmdq_conf_default.rxmode.jumbo_frame = 1;
-						vmdq_conf_default.rxmode.max_rx_pkt_len
-							= JUMBO_FRAME_MAX_SIZE;
-						VHOST_FEATURES = (1ULL << VIRTIO_NET_F_MRG_RXBUF);
-					}
-				}
-			}
-
-			/* Enable/disable stats. */
-			if (!strncmp(long_option[option_index].name, "stats", MAX_LONG_OPT_SZ)) {
-				ret = parse_num_opt(optarg, INT32_MAX);
-				if (ret == -1) {
-					RTE_LOG(INFO, VHOST_CONFIG, "Invalid argument for stats [0..N]\n");
-					us_vhost_usage(prgname);
-					return -1;
-				} else {
-					enable_stats = ret;
-				}
-			}
-
-			/* Set character device basename. */
-			if (!strncmp(long_option[option_index].name, "dev-basename", MAX_LONG_OPT_SZ)) {
-				if (us_vhost_parse_basename(optarg) == -1) {
-					RTE_LOG(INFO, VHOST_CONFIG, "Invalid argument for character device basename (Max %d characters)\n", MAX_BASENAME_SZ);
-					us_vhost_usage(prgname);
-					return -1;
-				}
-			}
-
-			/* Set character device index. */
-			if (!strncmp(long_option[option_index].name, "dev-index", MAX_LONG_OPT_SZ)) {
-				ret = parse_num_opt(optarg, INT32_MAX);
-				if (ret == -1) {
-					RTE_LOG(INFO, VHOST_CONFIG, "Invalid argument for character device index [0..N]\n");
-					us_vhost_usage(prgname);
-					return -1;
-				} else
-					dev_index = ret;
-			}
-
-			/* Enable/disable rx/tx zero copy. */
-			if (!strncmp(long_option[option_index].name,
-				"zero-copy", MAX_LONG_OPT_SZ)) {
-				ret = parse_num_opt(optarg, 1);
-				if (ret == -1) {
-					RTE_LOG(INFO, VHOST_CONFIG,
-						"Invalid argument"
-						" for zero-copy [0|1]\n");
-					us_vhost_usage(prgname);
-					return -1;
-				} else
-					zero_copy = ret;
-
-				if (zero_copy) {
-#ifdef RTE_MBUF_REFCNT
-					RTE_LOG(ERR, VHOST_CONFIG, "Before running "
-					"zero copy vhost APP, please "
-					"disable RTE_MBUF_REFCNT\n"
-					"in config file and then rebuild DPDK "
-					"core lib!\n"
-					"Otherwise please disable zero copy "
-					"flag in command line!\n");
-					return -1;
-#endif
-				}
-			}
-
-			/* Specify the descriptor number on RX. */
-			if (!strncmp(long_option[option_index].name,
-				"rx-desc-num", MAX_LONG_OPT_SZ)) {
-				ret = parse_num_opt(optarg, MAX_RING_DESC);
-				if ((ret == -1) || (!POWEROF2(ret))) {
-					RTE_LOG(INFO, VHOST_CONFIG,
-					"Invalid argument for rx-desc-num[0-N],"
-					"power of 2 required.\n");
-					us_vhost_usage(prgname);
-					return -1;
-				} else {
-					num_rx_descriptor = ret;
-				}
-			}
-
-			/* Specify the descriptor number on TX. */
-			if (!strncmp(long_option[option_index].name,
-				"tx-desc-num", MAX_LONG_OPT_SZ)) {
-				ret = parse_num_opt(optarg, MAX_RING_DESC);
-				if ((ret == -1) || (!POWEROF2(ret))) {
-					RTE_LOG(INFO, VHOST_CONFIG,
-					"Invalid argument for tx-desc-num [0-N],"
-					"power of 2 required.\n");
-					us_vhost_usage(prgname);
-					return -1;
-				} else {
-					num_tx_descriptor = ret;
-				}
-			}
-
-			break;
-
-			/* Invalid option - print options. */
-		default:
-			us_vhost_usage(prgname);
-			return -1;
-		}
-	}
-
-	for (i = 0; i < RTE_MAX_ETHPORTS; i++) {
-		if (enabled_port_mask & (1 << i))
-			ports[num_ports++] = (uint8_t)i;
-	}
-
-	if ((num_ports ==  0) || (num_ports > MAX_SUP_PORTS)) {
-		RTE_LOG(INFO, VHOST_PORT, "Current enabled port number is %u,"
-			"but only %u port can be enabled\n",num_ports, MAX_SUP_PORTS);
-		return -1;
-	}
-
-	if ((zero_copy == 1) && (vm2vm_mode == VM2VM_SOFTWARE)) {
-		RTE_LOG(INFO, VHOST_PORT,
-			"Vhost zero copy doesn't support software vm2vm,"
-			"please specify 'vm2vm 2' to use hardware vm2vm.\n");
-		return -1;
-	}
-
-	if ((zero_copy == 1) && (vmdq_conf_default.rxmode.jumbo_frame == 1)) {
-		RTE_LOG(INFO, VHOST_PORT,
-			"Vhost zero copy doesn't support jumbo frame,"
-			"please specify '--mergeable 0' to disable the "
-			"mergeable feature.\n");
-		return -1;
-	}
-
-	return 0;
-}
-
-/*
- * Update the global var NUM_PORTS and array PORTS according to system ports number
- * and return valid ports number
- */
-static unsigned check_ports_num(unsigned nb_ports)
-{
-	unsigned valid_num_ports = num_ports;
-	unsigned portid;
-
-	if (num_ports > nb_ports) {
-		RTE_LOG(INFO, VHOST_PORT, "\nSpecified port number(%u) exceeds total system port number(%u)\n",
-			num_ports, nb_ports);
-		num_ports = nb_ports;
-	}
-
-	for (portid = 0; portid < num_ports; portid ++) {
-		if (ports[portid] >= nb_ports) {
-			RTE_LOG(INFO, VHOST_PORT, "\nSpecified port ID(%u) exceeds max system port ID(%u)\n",
-				ports[portid], (nb_ports - 1));
-			ports[portid] = INVALID_PORT_ID;
-			valid_num_ports--;
-		}
-	}
-	return valid_num_ports;
-}
-
-/*
- * Macro to print out packet contents. Wrapped in debug define so that the
- * data path is not effected when debug is disabled.
- */
-#ifdef DEBUG
-#define PRINT_PACKET(device, addr, size, header) do {																\
-	char *pkt_addr = (char*)(addr);																					\
-	unsigned int index;																								\
-	char packet[MAX_PRINT_BUFF];																					\
-																													\
-	if ((header))																									\
-		snprintf(packet, MAX_PRINT_BUFF, "(%"PRIu64") Header size %d: ", (device->device_fh), (size));				\
-	else																											\
-		snprintf(packet, MAX_PRINT_BUFF, "(%"PRIu64") Packet size %d: ", (device->device_fh), (size));				\
-	for (index = 0; index < (size); index++) {																		\
-		snprintf(packet + strnlen(packet, MAX_PRINT_BUFF), MAX_PRINT_BUFF - strnlen(packet, MAX_PRINT_BUFF),	\
-			"%02hhx ", pkt_addr[index]);																			\
-	}																												\
-	snprintf(packet + strnlen(packet, MAX_PRINT_BUFF), MAX_PRINT_BUFF - strnlen(packet, MAX_PRINT_BUFF), "\n");	\
-																													\
-	LOG_DEBUG(VHOST_DATA, "%s", packet);																					\
-} while(0)
-#else
-#define PRINT_PACKET(device, addr, size, header) do{} while(0)
-#endif
-
-/*
- * Function to convert guest physical addresses to vhost virtual addresses. This
- * is used to convert virtio buffer addresses.
- */
-static inline uint64_t __attribute__((always_inline))
-gpa_to_vva(struct virtio_net *dev, uint64_t guest_pa)
-{
-	struct virtio_memory_regions *region;
-	uint32_t regionidx;
-	uint64_t vhost_va = 0;
-
-	for (regionidx = 0; regionidx < dev->mem->nregions; regionidx++) {
-		region = &dev->mem->regions[regionidx];
-		if ((guest_pa >= region->guest_phys_address) &&
-			(guest_pa <= region->guest_phys_address_end)) {
-			vhost_va = region->address_offset + guest_pa;
-			break;
-		}
-	}
-	LOG_DEBUG(VHOST_DATA, "(%"PRIu64") GPA %p| VVA %p\n",
-		dev->device_fh, (void*)(uintptr_t)guest_pa, (void*)(uintptr_t)vhost_va);
-
-	return vhost_va;
-}
-
-/*
- * Function to convert guest physical addresses to vhost physical addresses.
- * This is used to convert virtio buffer addresses.
- */
-static inline uint64_t __attribute__((always_inline))
-gpa_to_hpa(struct virtio_net *dev, uint64_t guest_pa,
-	uint32_t buf_len, hpa_type *addr_type)
-{
-	struct virtio_memory_regions_hpa *region;
-	uint32_t regionidx;
-	uint64_t vhost_pa = 0;
-
-	*addr_type = PHYS_ADDR_INVALID;
-
-	for (regionidx = 0; regionidx < dev->mem->nregions_hpa; regionidx++) {
-		region = &dev->mem->regions_hpa[regionidx];
-		if ((guest_pa >= region->guest_phys_address) &&
-			(guest_pa <= region->guest_phys_address_end)) {
-			vhost_pa = region->host_phys_addr_offset + guest_pa;
-			if (likely((guest_pa + buf_len - 1)
-				<= region->guest_phys_address_end))
-				*addr_type = PHYS_ADDR_CONTINUOUS;
-			else
-				*addr_type = PHYS_ADDR_CROSS_SUBREG;
-			break;
-		}
-	}
-
-	LOG_DEBUG(VHOST_DATA, "(%"PRIu64") GPA %p| HPA %p\n",
-		dev->device_fh, (void *)(uintptr_t)guest_pa,
-		(void *)(uintptr_t)vhost_pa);
-
-	return vhost_pa;
-}
-
-/*
- * This function adds buffers to the virtio devices RX virtqueue. Buffers can
- * be received from the physical port or from another virtio device. A packet
- * count is returned to indicate the number of packets that were succesfully
- * added to the RX queue. This function works when mergeable is disabled.
- */
-static inline uint32_t __attribute__((always_inline))
-virtio_dev_rx(struct virtio_net *dev, struct rte_mbuf **pkts, uint32_t count)
-{
-	struct vhost_virtqueue *vq;
-	struct vring_desc *desc;
-	struct rte_mbuf *buff;
-	/* The virtio_hdr is initialised to 0. */
-	struct virtio_net_hdr_mrg_rxbuf virtio_hdr = {{0,0,0,0,0,0},0};
-	uint64_t buff_addr = 0;
-	uint64_t buff_hdr_addr = 0;
-	uint32_t head[MAX_PKT_BURST], packet_len = 0;
-	uint32_t head_idx, packet_success = 0;
-	uint32_t retry = 0;
-	uint16_t avail_idx, res_cur_idx;
-	uint16_t res_base_idx, res_end_idx;
-	uint16_t free_entries;
-	uint8_t success = 0;
-
-	LOG_DEBUG(VHOST_DATA, "(%"PRIu64") virtio_dev_rx()\n", dev->device_fh);
-	vq = dev->virtqueue[VIRTIO_RXQ];
-	count = (count > MAX_PKT_BURST) ? MAX_PKT_BURST : count;
-
-	/* As many data cores may want access to available buffers, they need to be reserved. */
-	do {
-		res_base_idx = vq->last_used_idx_res;
-		avail_idx = *((volatile uint16_t *)&vq->avail->idx);
-
-		free_entries = (avail_idx - res_base_idx);
-		/* If retry is enabled and the queue is full then we wait and retry to avoid packet loss. */
-		if (enable_retry && unlikely(count > free_entries)) {
-			for (retry = 0; retry < burst_rx_retry_num; retry++) {
-				rte_delay_us(burst_rx_delay_time);
-				avail_idx =
-					*((volatile uint16_t *)&vq->avail->idx);
-				free_entries = (avail_idx - res_base_idx);
-				if (count <= free_entries)
-					break;
-			}
-		}
-
-		/*check that we have enough buffers*/
-		if (unlikely(count > free_entries))
-			count = free_entries;
-
-		if (count == 0)
-			return 0;
-
-		res_end_idx = res_base_idx + count;
-		/* vq->last_used_idx_res is atomically updated. */
-		success = rte_atomic16_cmpset(&vq->last_used_idx_res, res_base_idx,
-									res_end_idx);
-	} while (unlikely(success == 0));
-	res_cur_idx = res_base_idx;
-	LOG_DEBUG(VHOST_DATA, "(%"PRIu64") Current Index %d| End Index %d\n", dev->device_fh, res_cur_idx, res_end_idx);
-
-	/* Prefetch available ring to retrieve indexes. */
-	rte_prefetch0(&vq->avail->ring[res_cur_idx & (vq->size - 1)]);
-
-	/* Retrieve all of the head indexes first to avoid caching issues. */
-	for (head_idx = 0; head_idx < count; head_idx++)
-		head[head_idx] = vq->avail->ring[(res_cur_idx + head_idx) & (vq->size - 1)];
-
-	/*Prefetch descriptor index. */
-	rte_prefetch0(&vq->desc[head[packet_success]]);
-
-	while (res_cur_idx != res_end_idx) {
-		/* Get descriptor from available ring */
-		desc = &vq->desc[head[packet_success]];
-
-		buff = pkts[packet_success];
-
-		/* Convert from gpa to vva (guest physical addr -> vhost virtual addr) */
-		buff_addr = gpa_to_vva(dev, desc->addr);
-		/* Prefetch buffer address. */
-		rte_prefetch0((void*)(uintptr_t)buff_addr);
-
-		/* Copy virtio_hdr to packet and increment buffer address */
-		buff_hdr_addr = buff_addr;
-		packet_len = rte_pktmbuf_data_len(buff) + vq->vhost_hlen;
-
-		/*
-		 * If the descriptors are chained the header and data are
-		 * placed in separate buffers.
-		 */
-		if (desc->flags & VRING_DESC_F_NEXT) {
-			desc->len = vq->vhost_hlen;
-			desc = &vq->desc[desc->next];
-			/* Buffer address translation. */
-			buff_addr = gpa_to_vva(dev, desc->addr);
-			desc->len = rte_pktmbuf_data_len(buff);
-		} else {
-			buff_addr += vq->vhost_hlen;
-			desc->len = packet_len;
-		}
-
-		/* Update used ring with desc information */
-		vq->used->ring[res_cur_idx & (vq->size - 1)].id = head[packet_success];
-		vq->used->ring[res_cur_idx & (vq->size - 1)].len = packet_len;
-
-		/* Copy mbuf data to buffer */
-		rte_memcpy((void *)(uintptr_t)buff_addr,
-			rte_pktmbuf_mtod(buff, const void *),
-			rte_pktmbuf_data_len(buff));
-		PRINT_PACKET(dev, (uintptr_t)buff_addr,
-			rte_pktmbuf_data_len(buff), 0);
-
-		res_cur_idx++;
-		packet_success++;
-
-		rte_memcpy((void *)(uintptr_t)buff_hdr_addr,
-			(const void *)&virtio_hdr, vq->vhost_hlen);
-
-		PRINT_PACKET(dev, (uintptr_t)buff_hdr_addr, vq->vhost_hlen, 1);
-
-		if (res_cur_idx < res_end_idx) {
-			/* Prefetch descriptor index. */
-			rte_prefetch0(&vq->desc[head[packet_success]]);
-		}
-	}
-
-	rte_compiler_barrier();
-
-	/* Wait until it's our turn to add our buffer to the used ring. */
-	while (unlikely(vq->last_used_idx != res_base_idx))
-		rte_pause();
-
-	*(volatile uint16_t *)&vq->used->idx += count;
-	vq->last_used_idx = res_end_idx;
-
-	/* Kick the guest if necessary. */
-	if (!(vq->avail->flags & VRING_AVAIL_F_NO_INTERRUPT))
-		eventfd_write((int)vq->kickfd, 1);
-	return count;
-}
-
-static inline uint32_t __attribute__((always_inline))
-copy_from_mbuf_to_vring(struct virtio_net *dev,
-	uint16_t res_base_idx, uint16_t res_end_idx,
-	struct rte_mbuf *pkt)
-{
-	uint32_t vec_idx = 0;
-	uint32_t entry_success = 0;
-	struct vhost_virtqueue *vq;
-	/* The virtio_hdr is initialised to 0. */
-	struct virtio_net_hdr_mrg_rxbuf virtio_hdr = {
-		{0, 0, 0, 0, 0, 0}, 0};
-	uint16_t cur_idx = res_base_idx;
-	uint64_t vb_addr = 0;
-	uint64_t vb_hdr_addr = 0;
-	uint32_t seg_offset = 0;
-	uint32_t vb_offset = 0;
-	uint32_t seg_avail;
-	uint32_t vb_avail;
-	uint32_t cpy_len, entry_len;
-
-	if (pkt == NULL)
-		return 0;
-
-	LOG_DEBUG(VHOST_DATA, "(%"PRIu64") Current Index %d| "
-		"End Index %d\n",
-		dev->device_fh, cur_idx, res_end_idx);
-
-	/*
-	 * Convert from gpa to vva
-	 * (guest physical addr -> vhost virtual addr)
-	 */
-	vq = dev->virtqueue[VIRTIO_RXQ];
-	vb_addr =
-		gpa_to_vva(dev, vq->buf_vec[vec_idx].buf_addr);
-	vb_hdr_addr = vb_addr;
-
-	/* Prefetch buffer address. */
-	rte_prefetch0((void *)(uintptr_t)vb_addr);
-
-	virtio_hdr.num_buffers = res_end_idx - res_base_idx;
-
-	LOG_DEBUG(VHOST_DATA, "(%"PRIu64") RX: Num merge buffers %d\n",
-		dev->device_fh, virtio_hdr.num_buffers);
-
-	rte_memcpy((void *)(uintptr_t)vb_hdr_addr,
-		(const void *)&virtio_hdr, vq->vhost_hlen);
-
-	PRINT_PACKET(dev, (uintptr_t)vb_hdr_addr, vq->vhost_hlen, 1);
-
-	seg_avail = rte_pktmbuf_data_len(pkt);
-	vb_offset = vq->vhost_hlen;
-	vb_avail =
-		vq->buf_vec[vec_idx].buf_len - vq->vhost_hlen;
-
-	entry_len = vq->vhost_hlen;
-
-	if (vb_avail == 0) {
-		uint32_t desc_idx =
-			vq->buf_vec[vec_idx].desc_idx;
-		vq->desc[desc_idx].len = vq->vhost_hlen;
-
-		if ((vq->desc[desc_idx].flags
-			& VRING_DESC_F_NEXT) == 0) {
-			/* Update used ring with desc information */
-			vq->used->ring[cur_idx & (vq->size - 1)].id
-				= vq->buf_vec[vec_idx].desc_idx;
-			vq->used->ring[cur_idx & (vq->size - 1)].len
-				= entry_len;
-
-			entry_len = 0;
-			cur_idx++;
-			entry_success++;
-		}
-
-		vec_idx++;
-		vb_addr =
-			gpa_to_vva(dev, vq->buf_vec[vec_idx].buf_addr);
-
-		/* Prefetch buffer address. */
-		rte_prefetch0((void *)(uintptr_t)vb_addr);
-		vb_offset = 0;
-		vb_avail = vq->buf_vec[vec_idx].buf_len;
-	}
-
-	cpy_len = RTE_MIN(vb_avail, seg_avail);
-
-	while (cpy_len > 0) {
-		/* Copy mbuf data to vring buffer */
-		rte_memcpy((void *)(uintptr_t)(vb_addr + vb_offset),
-			(const void *)(rte_pktmbuf_mtod(pkt, char*) + seg_offset),
-			cpy_len);
-
-		PRINT_PACKET(dev,
-			(uintptr_t)(vb_addr + vb_offset),
-			cpy_len, 0);
-
-		seg_offset += cpy_len;
-		vb_offset += cpy_len;
-		seg_avail -= cpy_len;
-		vb_avail -= cpy_len;
-		entry_len += cpy_len;
-
-		if (seg_avail != 0) {
-			/*
-			 * The virtio buffer in this vring
-			 * entry reach to its end.
-			 * But the segment doesn't complete.
-			 */
-			if ((vq->desc[vq->buf_vec[vec_idx].desc_idx].flags &
-				VRING_DESC_F_NEXT) == 0) {
-				/* Update used ring with desc information */
-				vq->used->ring[cur_idx & (vq->size - 1)].id
-					= vq->buf_vec[vec_idx].desc_idx;
-				vq->used->ring[cur_idx & (vq->size - 1)].len
-					= entry_len;
-				entry_len = 0;
-				cur_idx++;
-				entry_success++;
-			}
-
-			vec_idx++;
-			vb_addr = gpa_to_vva(dev,
-				vq->buf_vec[vec_idx].buf_addr);
-			vb_offset = 0;
-			vb_avail = vq->buf_vec[vec_idx].buf_len;
-			cpy_len = RTE_MIN(vb_avail, seg_avail);
-		} else {
-			/*
-			 * This current segment complete, need continue to
-			 * check if the whole packet complete or not.
-			 */
-			pkt = pkt->next;
-			if (pkt != NULL) {
-				/*
-				 * There are more segments.
-				 */
-				if (vb_avail == 0) {
-					/*
-					 * This current buffer from vring is
-					 * used up, need fetch next buffer
-					 * from buf_vec.
-					 */
-					uint32_t desc_idx =
-						vq->buf_vec[vec_idx].desc_idx;
-					vq->desc[desc_idx].len = vb_offset;
-
-					if ((vq->desc[desc_idx].flags &
-						VRING_DESC_F_NEXT) == 0) {
-						uint16_t wrapped_idx =
-							cur_idx & (vq->size - 1);
-						/*
-						 * Update used ring with the
-						 * descriptor information
-						 */
-						vq->used->ring[wrapped_idx].id
-							= desc_idx;
-						vq->used->ring[wrapped_idx].len
-							= entry_len;
-						entry_success++;
-						entry_len = 0;
-						cur_idx++;
-					}
-
-					/* Get next buffer from buf_vec. */
-					vec_idx++;
-					vb_addr = gpa_to_vva(dev,
-						vq->buf_vec[vec_idx].buf_addr);
-					vb_avail =
-						vq->buf_vec[vec_idx].buf_len;
-					vb_offset = 0;
-				}
-
-				seg_offset = 0;
-				seg_avail = rte_pktmbuf_data_len(pkt);
-				cpy_len = RTE_MIN(vb_avail, seg_avail);
-			} else {
-				/*
-				 * This whole packet completes.
-				 */
-				uint32_t desc_idx =
-					vq->buf_vec[vec_idx].desc_idx;
-				vq->desc[desc_idx].len = vb_offset;
-
-				while (vq->desc[desc_idx].flags &
-					VRING_DESC_F_NEXT) {
-					desc_idx = vq->desc[desc_idx].next;
-					 vq->desc[desc_idx].len = 0;
-				}
-
-				/* Update used ring with desc information */
-				vq->used->ring[cur_idx & (vq->size - 1)].id
-					= vq->buf_vec[vec_idx].desc_idx;
-				vq->used->ring[cur_idx & (vq->size - 1)].len
-					= entry_len;
-				entry_len = 0;
-				cur_idx++;
-				entry_success++;
-				seg_avail = 0;
-				cpy_len = RTE_MIN(vb_avail, seg_avail);
-			}
-		}
-	}
-
-	return entry_success;
-}
-
-/*
- * This function adds buffers to the virtio devices RX virtqueue. Buffers can
- * be received from the physical port or from another virtio device. A packet
- * count is returned to indicate the number of packets that were succesfully
- * added to the RX queue. This function works for mergeable RX.
- */
-static inline uint32_t __attribute__((always_inline))
-virtio_dev_merge_rx(struct virtio_net *dev, struct rte_mbuf **pkts,
-	uint32_t count)
-{
-	struct vhost_virtqueue *vq;
-	uint32_t pkt_idx = 0, entry_success = 0;
-	uint32_t retry = 0;
-	uint16_t avail_idx, res_cur_idx;
-	uint16_t res_base_idx, res_end_idx;
-	uint8_t success = 0;
-
-	LOG_DEBUG(VHOST_DATA, "(%"PRIu64") virtio_dev_merge_rx()\n",
-		dev->device_fh);
-	vq = dev->virtqueue[VIRTIO_RXQ];
-	count = RTE_MIN((uint32_t)MAX_PKT_BURST, count);
-
-	if (count == 0)
-		return 0;
-
-	for (pkt_idx = 0; pkt_idx < count; pkt_idx++) {
-		uint32_t secure_len = 0;
-		uint16_t need_cnt;
-		uint32_t vec_idx = 0;
-		uint32_t pkt_len = pkts[pkt_idx]->pkt_len + vq->vhost_hlen;
-		uint16_t i, id;
-
-		do {
-			/*
-			 * As many data cores may want access to available
-			 * buffers, they need to be reserved.
-			 */
-			res_base_idx = vq->last_used_idx_res;
-			res_cur_idx = res_base_idx;
-
-			do {
-				avail_idx = *((volatile uint16_t *)&vq->avail->idx);
-				if (unlikely(res_cur_idx == avail_idx)) {
-					/*
-					 * If retry is enabled and the queue is
-					 * full then we wait and retry to avoid
-					 * packet loss.
-					 */
-					if (enable_retry) {
-						uint8_t cont = 0;
-						for (retry = 0; retry < burst_rx_retry_num; retry++) {
-							rte_delay_us(burst_rx_delay_time);
-							avail_idx =
-								*((volatile uint16_t *)&vq->avail->idx);
-							if (likely(res_cur_idx != avail_idx)) {
-								cont = 1;
-								break;
-							}
-						}
-						if (cont == 1)
-							continue;
-					}
-
-					LOG_DEBUG(VHOST_DATA,
-						"(%"PRIu64") Failed "
-						"to get enough desc from "
-						"vring\n",
-						dev->device_fh);
-					return pkt_idx;
-				} else {
-					uint16_t wrapped_idx =
-						(res_cur_idx) & (vq->size - 1);
-					uint32_t idx =
-						vq->avail->ring[wrapped_idx];
-					uint8_t next_desc;
-
-					do {
-						next_desc = 0;
-						secure_len += vq->desc[idx].len;
-						if (vq->desc[idx].flags &
-							VRING_DESC_F_NEXT) {
-							idx = vq->desc[idx].next;
-							next_desc = 1;
-						}
-					} while (next_desc);
-
-					res_cur_idx++;
-				}
-			} while (pkt_len > secure_len);
-
-			/* vq->last_used_idx_res is atomically updated. */
-			success = rte_atomic16_cmpset(&vq->last_used_idx_res,
-							res_base_idx,
-							res_cur_idx);
-		} while (success == 0);
-
-		id = res_base_idx;
-		need_cnt = res_cur_idx - res_base_idx;
-
-		for (i = 0; i < need_cnt; i++, id++) {
-			uint16_t wrapped_idx = id & (vq->size - 1);
-			uint32_t idx = vq->avail->ring[wrapped_idx];
-			uint8_t next_desc;
-			do {
-				next_desc = 0;
-				vq->buf_vec[vec_idx].buf_addr =
-					vq->desc[idx].addr;
-				vq->buf_vec[vec_idx].buf_len =
-					vq->desc[idx].len;
-				vq->buf_vec[vec_idx].desc_idx = idx;
-				vec_idx++;
-
-				if (vq->desc[idx].flags & VRING_DESC_F_NEXT) {
-					idx = vq->desc[idx].next;
-					next_desc = 1;
-				}
-			} while (next_desc);
-		}
-
-		res_end_idx = res_cur_idx;
-
-		entry_success = copy_from_mbuf_to_vring(dev, res_base_idx,
-			res_end_idx, pkts[pkt_idx]);
-
-		rte_compiler_barrier();
-
-		/*
-		 * Wait until it's our turn to add our buffer
-		 * to the used ring.
-		 */
-		while (unlikely(vq->last_used_idx != res_base_idx))
-			rte_pause();
-
-		*(volatile uint16_t *)&vq->used->idx += entry_success;
-		vq->last_used_idx = res_end_idx;
-
-		/* Kick the guest if necessary. */
-		if (!(vq->avail->flags & VRING_AVAIL_F_NO_INTERRUPT))
-			eventfd_write((int)vq->kickfd, 1);
-	}
-
-	return count;
-}
-
-/*
- * Compares a packet destination MAC address to a device MAC address.
- */
-static inline int __attribute__((always_inline))
-ether_addr_cmp(struct ether_addr *ea, struct ether_addr *eb)
-{
-	return (((*(uint64_t *)ea ^ *(uint64_t *)eb) & MAC_ADDR_CMP) == 0);
-}
-
-/*
- * This function learns the MAC address of the device and registers this along with a
- * vlan tag to a VMDQ.
- */
-static int
-link_vmdq(struct virtio_net *dev, struct rte_mbuf *m)
-{
-	struct ether_hdr *pkt_hdr;
-	struct virtio_net_data_ll *dev_ll;
-	int i, ret;
-
-	/* Learn MAC address of guest device from packet */
-	pkt_hdr = rte_pktmbuf_mtod(m, struct ether_hdr *);
-
-	dev_ll = ll_root_used;
-
-	while (dev_ll != NULL) {
-		if (ether_addr_cmp(&(pkt_hdr->s_addr), &dev_ll->dev->mac_address)) {
-			RTE_LOG(INFO, VHOST_DATA, "(%"PRIu64") WARNING: This device is using an existing MAC address and has not been registered.\n", dev->device_fh);
-			return -1;
-		}
-		dev_ll = dev_ll->next;
-	}
-
-	for (i = 0; i < ETHER_ADDR_LEN; i++)
-		dev->mac_address.addr_bytes[i] = pkt_hdr->s_addr.addr_bytes[i];
-
-	/* vlan_tag currently uses the device_id. */
-	dev->vlan_tag = vlan_tags[dev->device_fh];
-
-	/* Print out VMDQ registration info. */
-	RTE_LOG(INFO, VHOST_DATA, "(%"PRIu64") MAC_ADDRESS %02x:%02x:%02x:%02x:%02x:%02x and VLAN_TAG %d registered\n",
-		dev->device_fh,
-		dev->mac_address.addr_bytes[0], dev->mac_address.addr_bytes[1],
-		dev->mac_address.addr_bytes[2], dev->mac_address.addr_bytes[3],
-		dev->mac_address.addr_bytes[4], dev->mac_address.addr_bytes[5],
-		dev->vlan_tag);
-
-	/* Register the MAC address. */
-	ret = rte_eth_dev_mac_addr_add(ports[0], &dev->mac_address, (uint32_t)dev->device_fh);
-	if (ret)
-		RTE_LOG(ERR, VHOST_DATA, "(%"PRIu64") Failed to add device MAC address to VMDQ\n",
-					dev->device_fh);
-
-	/* Enable stripping of the vlan tag as we handle routing. */
-	rte_eth_dev_set_vlan_strip_on_queue(ports[0], (uint16_t)dev->vmdq_rx_q, 1);
-
-	/* Set device as ready for RX. */
-	dev->ready = DEVICE_RX;
-
-	return 0;
-}
-
-/*
- * Removes MAC address and vlan tag from VMDQ. Ensures that nothing is adding buffers to the RX
- * queue before disabling RX on the device.
- */
-static inline void
-unlink_vmdq(struct virtio_net *dev)
-{
-	unsigned i = 0;
-	unsigned rx_count;
-	struct rte_mbuf *pkts_burst[MAX_PKT_BURST];
-
-	if (dev->ready == DEVICE_RX) {
-		/*clear MAC and VLAN settings*/
-		rte_eth_dev_mac_addr_remove(ports[0], &dev->mac_address);
-		for (i = 0; i < 6; i++)
-			dev->mac_address.addr_bytes[i] = 0;
-
-		dev->vlan_tag = 0;
-
-		/*Clear out the receive buffers*/
-		rx_count = rte_eth_rx_burst(ports[0],
-					(uint16_t)dev->vmdq_rx_q, pkts_burst, MAX_PKT_BURST);
-
-		while (rx_count) {
-			for (i = 0; i < rx_count; i++)
-				rte_pktmbuf_free(pkts_burst[i]);
-
-			rx_count = rte_eth_rx_burst(ports[0],
-					(uint16_t)dev->vmdq_rx_q, pkts_burst, MAX_PKT_BURST);
-		}
-
-		dev->ready = DEVICE_MAC_LEARNING;
-	}
-}
-
-/*
- * Check if the packet destination MAC address is for a local device. If so then put
- * the packet on that devices RX queue. If not then return.
- */
-static inline unsigned __attribute__((always_inline))
-virtio_tx_local(struct virtio_net *dev, struct rte_mbuf *m)
-{
-	struct virtio_net_data_ll *dev_ll;
-	struct ether_hdr *pkt_hdr;
-	uint64_t ret = 0;
-
-	pkt_hdr = rte_pktmbuf_mtod(m, struct ether_hdr *);
-
-	/*get the used devices list*/
-	dev_ll = ll_root_used;
-
-	while (dev_ll != NULL) {
-		if ((dev_ll->dev->ready == DEVICE_RX) && ether_addr_cmp(&(pkt_hdr->d_addr),
-				          &dev_ll->dev->mac_address)) {
-
-			/* Drop the packet if the TX packet is destined for the TX device. */
-			if (dev_ll->dev->device_fh == dev->device_fh) {
-				LOG_DEBUG(VHOST_DATA, "(%"PRIu64") TX: Source and destination MAC addresses are the same. Dropping packet.\n",
-							dev_ll->dev->device_fh);
-				return 0;
-			}
-
-
-			LOG_DEBUG(VHOST_DATA, "(%"PRIu64") TX: MAC address is local\n", dev_ll->dev->device_fh);
-
-			if (dev_ll->dev->remove) {
-				/*drop the packet if the device is marked for removal*/
-				LOG_DEBUG(VHOST_DATA, "(%"PRIu64") Device is marked for removal\n", dev_ll->dev->device_fh);
-			} else {
-				uint32_t mergeable =
-					dev_ll->dev->features &
-					(1 << VIRTIO_NET_F_MRG_RXBUF);
-
-				/*send the packet to the local virtio device*/
-				if (likely(mergeable == 0))
-					ret = virtio_dev_rx(dev_ll->dev, &m, 1);
-				else
-					ret = virtio_dev_merge_rx(dev_ll->dev,
-						&m, 1);
-
-				if (enable_stats) {
-					rte_atomic64_add(
-					&dev_statistics[dev_ll->dev->device_fh].rx_total_atomic,
-					1);
-					rte_atomic64_add(
-					&dev_statistics[dev_ll->dev->device_fh].rx_atomic,
-					ret);
-					dev_statistics[dev->device_fh].tx_total++;
-					dev_statistics[dev->device_fh].tx += ret;
-				}
-			}
-
-			return 0;
-		}
-		dev_ll = dev_ll->next;
-	}
-
-	return -1;
-}
-
-/*
- * This function routes the TX packet to the correct interface. This may be a local device
- * or the physical port.
- */
-static inline void __attribute__((always_inline))
-virtio_tx_route(struct virtio_net* dev, struct rte_mbuf *m, struct rte_mempool *mbuf_pool, uint16_t vlan_tag)
-{
-	struct mbuf_table *tx_q;
-	struct vlan_ethhdr *vlan_hdr;
-	struct rte_mbuf **m_table;
-	struct rte_mbuf *mbuf, *prev;
-	unsigned len, ret, offset = 0;
-	const uint16_t lcore_id = rte_lcore_id();
-	struct virtio_net_data_ll *dev_ll = ll_root_used;
-	struct ether_hdr *pkt_hdr = rte_pktmbuf_mtod(m, struct ether_hdr *);
-
-	/*check if destination is local VM*/
-	if ((vm2vm_mode == VM2VM_SOFTWARE) && (virtio_tx_local(dev, m) == 0))
-		return;
-
-	if (vm2vm_mode == VM2VM_HARDWARE) {
-		while (dev_ll != NULL) {
-			if ((dev_ll->dev->ready == DEVICE_RX)
-				&& ether_addr_cmp(&(pkt_hdr->d_addr),
-				&dev_ll->dev->mac_address)) {
-				/*
-				 * Drop the packet if the TX packet is
-				 * destined for the TX device.
-				 */
-				if (dev_ll->dev->device_fh == dev->device_fh) {
-					LOG_DEBUG(VHOST_DATA,
-					"(%"PRIu64") TX: Source and destination"
-					" MAC addresses are the same. Dropping "
-					"packet.\n",
-					dev_ll->dev->device_fh);
-					return;
-				}
-				offset = 4;
-				vlan_tag =
-				(uint16_t)
-				vlan_tags[(uint16_t)dev_ll->dev->device_fh];
-
-				LOG_DEBUG(VHOST_DATA,
-				"(%"PRIu64") TX: pkt to local VM device id:"
-				"(%"PRIu64") vlan tag: %d.\n",
-				dev->device_fh, dev_ll->dev->device_fh,
-				vlan_tag);
-
-				break;
-			}
-			dev_ll = dev_ll->next;
-		}
-	}
-
-	LOG_DEBUG(VHOST_DATA, "(%"PRIu64") TX: MAC address is external\n", dev->device_fh);
-
-	/*Add packet to the port tx queue*/
-	tx_q = &lcore_tx_queue[lcore_id];
-	len = tx_q->len;
-
-	/* Allocate an mbuf and populate the structure. */
-	mbuf = rte_pktmbuf_alloc(mbuf_pool);
-	if (unlikely(mbuf == NULL)) {
-		RTE_LOG(ERR, VHOST_DATA,
-			"Failed to allocate memory for mbuf.\n");
-		return;
-	}
-
-	mbuf->data_len = m->data_len + VLAN_HLEN + offset;
-	mbuf->pkt_len = m->pkt_len + VLAN_HLEN + offset;
-	mbuf->nb_segs = m->nb_segs;
-
-	/* Copy ethernet header to mbuf. */
-	rte_memcpy(rte_pktmbuf_mtod(mbuf, void *),
-		rte_pktmbuf_mtod(m, const void *),
-		ETH_HLEN);
-
-
-	/* Setup vlan header. Bytes need to be re-ordered for network with htons()*/
-	vlan_hdr = rte_pktmbuf_mtod(mbuf, struct vlan_ethhdr *);
-	vlan_hdr->h_vlan_encapsulated_proto = vlan_hdr->h_vlan_proto;
-	vlan_hdr->h_vlan_proto = htons(ETH_P_8021Q);
-	vlan_hdr->h_vlan_TCI = htons(vlan_tag);
-
-	/* Copy the remaining packet contents to the mbuf. */
-	rte_memcpy((void *)(rte_pktmbuf_mtod(mbuf, uint8_t *) + VLAN_ETH_HLEN),
-		(const void *)(rte_pktmbuf_mtod(m, uint8_t *) + ETH_HLEN),
-		(m->data_len - ETH_HLEN));
-
-	/* Copy the remaining segments for the whole packet. */
-	prev = mbuf;
-	while (m->next) {
-		/* Allocate an mbuf and populate the structure. */
-		struct rte_mbuf *next_mbuf = rte_pktmbuf_alloc(mbuf_pool);
-		if (unlikely(next_mbuf == NULL)) {
-			rte_pktmbuf_free(mbuf);
-			RTE_LOG(ERR, VHOST_DATA,
-				"Failed to allocate memory for mbuf.\n");
-			return;
-		}
-
-		m = m->next;
-		prev->next = next_mbuf;
-		prev = next_mbuf;
-		next_mbuf->data_len = m->data_len;
-
-		/* Copy data to next mbuf. */
-		rte_memcpy(rte_pktmbuf_mtod(next_mbuf, void *),
-			rte_pktmbuf_mtod(m, const void *), m->data_len);
-	}
-
-	tx_q->m_table[len] = mbuf;
-	len++;
-	if (enable_stats) {
-		dev_statistics[dev->device_fh].tx_total++;
-		dev_statistics[dev->device_fh].tx++;
-	}
-
-	if (unlikely(len == MAX_PKT_BURST)) {
-		m_table = (struct rte_mbuf **)tx_q->m_table;
-		ret = rte_eth_tx_burst(ports[0], (uint16_t)tx_q->txq_id, m_table, (uint16_t) len);
-		/* Free any buffers not handled by TX and update the port stats. */
-		if (unlikely(ret < len)) {
-			do {
-				rte_pktmbuf_free(m_table[ret]);
-			} while (++ret < len);
-		}
-
-		len = 0;
-	}
-
-	tx_q->len = len;
-	return;
-}
-
-static inline void __attribute__((always_inline))
-virtio_dev_tx(struct virtio_net* dev, struct rte_mempool *mbuf_pool)
-{
-	struct rte_mbuf m;
-	struct vhost_virtqueue *vq;
-	struct vring_desc *desc;
-	uint64_t buff_addr = 0;
-	uint32_t head[MAX_PKT_BURST];
-	uint32_t used_idx;
-	uint32_t i;
-	uint16_t free_entries, packet_success = 0;
-	uint16_t avail_idx;
-
-	vq = dev->virtqueue[VIRTIO_TXQ];
-	avail_idx =  *((volatile uint16_t *)&vq->avail->idx);
-
-	/* If there are no available buffers then return. */
-	if (vq->last_used_idx == avail_idx)
-		return;
-
-	LOG_DEBUG(VHOST_DATA, "(%"PRIu64") virtio_dev_tx()\n", dev->device_fh);
-
-	/* Prefetch available ring to retrieve head indexes. */
-	rte_prefetch0(&vq->avail->ring[vq->last_used_idx & (vq->size - 1)]);
-
-	/*get the number of free entries in the ring*/
-	free_entries = (avail_idx - vq->last_used_idx);
-
-	/* Limit to MAX_PKT_BURST. */
-	if (free_entries > MAX_PKT_BURST)
-		free_entries = MAX_PKT_BURST;
-
-	LOG_DEBUG(VHOST_DATA, "(%"PRIu64") Buffers available %d\n", dev->device_fh, free_entries);
-	/* Retrieve all of the head indexes first to avoid caching issues. */
-	for (i = 0; i < free_entries; i++)
-		head[i] = vq->avail->ring[(vq->last_used_idx + i) & (vq->size - 1)];
-
-	/* Prefetch descriptor index. */
-	rte_prefetch0(&vq->desc[head[packet_success]]);
-	rte_prefetch0(&vq->used->ring[vq->last_used_idx & (vq->size - 1)]);
-
-	while (packet_success < free_entries) {
-		desc = &vq->desc[head[packet_success]];
-
-		/* Discard first buffer as it is the virtio header */
-		desc = &vq->desc[desc->next];
-
-		/* Buffer address translation. */
-		buff_addr = gpa_to_vva(dev, desc->addr);
-		/* Prefetch buffer address. */
-		rte_prefetch0((void*)(uintptr_t)buff_addr);
-
-		used_idx = vq->last_used_idx & (vq->size - 1);
-
-		if (packet_success < (free_entries - 1)) {
-			/* Prefetch descriptor index. */
-			rte_prefetch0(&vq->desc[head[packet_success+1]]);
-			rte_prefetch0(&vq->used->ring[(used_idx + 1) & (vq->size - 1)]);
-		}
-
-		/* Update used index buffer information. */
-		vq->used->ring[used_idx].id = head[packet_success];
-		vq->used->ring[used_idx].len = 0;
-
-		/* Setup dummy mbuf. This is copied to a real mbuf if transmitted out the physical port. */
-		m.data_len = desc->len;
-		m.pkt_len = desc->len;
-		m.data_off = 0;
-
-		PRINT_PACKET(dev, (uintptr_t)buff_addr, desc->len, 0);
-
-		/* If this is the first received packet we need to learn the MAC and setup VMDQ */
-		if (dev->ready == DEVICE_MAC_LEARNING) {
-			if (dev->remove || (link_vmdq(dev, &m) == -1)) {
-				/*discard frame if device is scheduled for removal or a duplicate MAC address is found. */
-				packet_success += free_entries;
-				vq->last_used_idx += packet_success;
-				break;
-			}
-		}
-		virtio_tx_route(dev, &m, mbuf_pool, (uint16_t)dev->device_fh);
-
-		vq->last_used_idx++;
-		packet_success++;
-	}
-
-	rte_compiler_barrier();
-	vq->used->idx += packet_success;
-	/* Kick guest if required. */
-	if (!(vq->avail->flags & VRING_AVAIL_F_NO_INTERRUPT))
-		eventfd_write((int)vq->kickfd, 1);
-}
-
-/* This function works for TX packets with mergeable feature enabled. */
-static inline void __attribute__((always_inline))
-virtio_dev_merge_tx(struct virtio_net *dev, struct rte_mempool *mbuf_pool)
-{
-	struct rte_mbuf *m, *prev;
-	struct vhost_virtqueue *vq;
-	struct vring_desc *desc;
-	uint64_t vb_addr = 0;
-	uint32_t head[MAX_PKT_BURST];
-	uint32_t used_idx;
-	uint32_t i;
-	uint16_t free_entries, entry_success = 0;
-	uint16_t avail_idx;
-	uint32_t buf_size = MBUF_SIZE - (sizeof(struct rte_mbuf)
-			+ RTE_PKTMBUF_HEADROOM);
-
-	vq = dev->virtqueue[VIRTIO_TXQ];
-	avail_idx =  *((volatile uint16_t *)&vq->avail->idx);
-
-	/* If there are no available buffers then return. */
-	if (vq->last_used_idx == avail_idx)
-		return;
-
-	LOG_DEBUG(VHOST_DATA, "(%"PRIu64") virtio_dev_merge_tx()\n",
-		dev->device_fh);
-
-	/* Prefetch available ring to retrieve head indexes. */
-	rte_prefetch0(&vq->avail->ring[vq->last_used_idx & (vq->size - 1)]);
-
-	/*get the number of free entries in the ring*/
-	free_entries = (avail_idx - vq->last_used_idx);
-
-	/* Limit to MAX_PKT_BURST. */
-	free_entries = RTE_MIN(free_entries, MAX_PKT_BURST);
-
-	LOG_DEBUG(VHOST_DATA, "(%"PRIu64") Buffers available %d\n",
-		dev->device_fh, free_entries);
-	/* Retrieve all of the head indexes first to avoid caching issues. */
-	for (i = 0; i < free_entries; i++)
-		head[i] = vq->avail->ring[(vq->last_used_idx + i) & (vq->size - 1)];
-
-	/* Prefetch descriptor index. */
-	rte_prefetch0(&vq->desc[head[entry_success]]);
-	rte_prefetch0(&vq->used->ring[vq->last_used_idx & (vq->size - 1)]);
-
-	while (entry_success < free_entries) {
-		uint32_t vb_avail, vb_offset;
-		uint32_t seg_avail, seg_offset;
-		uint32_t cpy_len;
-		uint32_t seg_num = 0;
-		struct rte_mbuf *cur;
-		uint8_t alloc_err = 0;
-
-		desc = &vq->desc[head[entry_success]];
-
-		/* Discard first buffer as it is the virtio header */
-		desc = &vq->desc[desc->next];
-
-		/* Buffer address translation. */
-		vb_addr = gpa_to_vva(dev, desc->addr);
-		/* Prefetch buffer address. */
-		rte_prefetch0((void *)(uintptr_t)vb_addr);
-
-		used_idx = vq->last_used_idx & (vq->size - 1);
-
-		if (entry_success < (free_entries - 1)) {
-			/* Prefetch descriptor index. */
-			rte_prefetch0(&vq->desc[head[entry_success+1]]);
-			rte_prefetch0(&vq->used->ring[(used_idx + 1) & (vq->size - 1)]);
-		}
-
-		/* Update used index buffer information. */
-		vq->used->ring[used_idx].id = head[entry_success];
-		vq->used->ring[used_idx].len = 0;
-
-		vb_offset = 0;
-		vb_avail = desc->len;
-		seg_offset = 0;
-		seg_avail = buf_size;
-		cpy_len = RTE_MIN(vb_avail, seg_avail);
-
-		PRINT_PACKET(dev, (uintptr_t)vb_addr, desc->len, 0);
-
-		/* Allocate an mbuf and populate the structure. */
-		m = rte_pktmbuf_alloc(mbuf_pool);
-		if (unlikely(m == NULL)) {
-			RTE_LOG(ERR, VHOST_DATA,
-				"Failed to allocate memory for mbuf.\n");
-			return;
-		}
-
-		seg_num++;
-		cur = m;
-		prev = m;
-		while (cpy_len != 0) {
-			rte_memcpy((void *)(rte_pktmbuf_mtod(cur, char *) + seg_offset),
-				(void *)((uintptr_t)(vb_addr + vb_offset)),
-				cpy_len);
-
-			seg_offset += cpy_len;
-			vb_offset += cpy_len;
-			vb_avail -= cpy_len;
-			seg_avail -= cpy_len;
-
-			if (vb_avail != 0) {
-				/*
-				 * The segment reachs to its end,
-				 * while the virtio buffer in TX vring has
-				 * more data to be copied.
-				 */
-				cur->data_len = seg_offset;
-				m->pkt_len += seg_offset;
-				/* Allocate mbuf and populate the structure. */
-				cur = rte_pktmbuf_alloc(mbuf_pool);
-				if (unlikely(cur == NULL)) {
-					RTE_LOG(ERR, VHOST_DATA, "Failed to "
-						"allocate memory for mbuf.\n");
-					rte_pktmbuf_free(m);
-					alloc_err = 1;
-					break;
-				}
-
-				seg_num++;
-				prev->next = cur;
-				prev = cur;
-				seg_offset = 0;
-				seg_avail = buf_size;
-			} else {
-				if (desc->flags & VRING_DESC_F_NEXT) {
-					/*
-					 * There are more virtio buffers in
-					 * same vring entry need to be copied.
-					 */
-					if (seg_avail == 0) {
-						/*
-						 * The current segment hasn't
-						 * room to accomodate more
-						 * data.
-						 */
-						cur->data_len = seg_offset;
-						m->pkt_len += seg_offset;
-						/*
-						 * Allocate an mbuf and
-						 * populate the structure.
-						 */
-						cur = rte_pktmbuf_alloc(mbuf_pool);
-						if (unlikely(cur == NULL)) {
-							RTE_LOG(ERR,
-								VHOST_DATA,
-								"Failed to "
-								"allocate memory "
-								"for mbuf\n");
-							rte_pktmbuf_free(m);
-							alloc_err = 1;
-							break;
-						}
-						seg_num++;
-						prev->next = cur;
-						prev = cur;
-						seg_offset = 0;
-						seg_avail = buf_size;
-					}
-
-					desc = &vq->desc[desc->next];
-
-					/* Buffer address translation. */
-					vb_addr = gpa_to_vva(dev, desc->addr);
-					/* Prefetch buffer address. */
-					rte_prefetch0((void *)(uintptr_t)vb_addr);
-					vb_offset = 0;
-					vb_avail = desc->len;
-
-					PRINT_PACKET(dev, (uintptr_t)vb_addr,
-						desc->len, 0);
-				} else {
-					/* The whole packet completes. */
-					cur->data_len = seg_offset;
-					m->pkt_len += seg_offset;
-					vb_avail = 0;
-				}
-			}
-
-			cpy_len = RTE_MIN(vb_avail, seg_avail);
-		}
-
-		if (unlikely(alloc_err == 1))
-			break;
-
-		m->nb_segs = seg_num;
-
-		/*
-		 * If this is the first received packet we need to learn
-		 * the MAC and setup VMDQ
-		 */
-		if (dev->ready == DEVICE_MAC_LEARNING) {
-			if (dev->remove || (link_vmdq(dev, m) == -1)) {
-				/*
-				 * Discard frame if device is scheduled for
-				 * removal or a duplicate MAC address is found.
-				 */
-				entry_success = free_entries;
-				vq->last_used_idx += entry_success;
-				rte_pktmbuf_free(m);
-				break;
-			}
-		}
-
-		virtio_tx_route(dev, m, mbuf_pool, (uint16_t)dev->device_fh);
-		vq->last_used_idx++;
-		entry_success++;
-		rte_pktmbuf_free(m);
-	}
-
-	rte_compiler_barrier();
-	vq->used->idx += entry_success;
-	/* Kick guest if required. */
-	if (!(vq->avail->flags & VRING_AVAIL_F_NO_INTERRUPT))
-		eventfd_write((int)vq->kickfd, 1);
-
-}
-
-/*
- * This function is called by each data core. It handles all RX/TX registered with the
- * core. For TX the specific lcore linked list is used. For RX, MAC addresses are compared
- * with all devices in the main linked list.
- */
-static int
-switch_worker(__attribute__((unused)) void *arg)
-{
-	struct rte_mempool *mbuf_pool = arg;
-	struct virtio_net *dev = NULL;
-	struct rte_mbuf *pkts_burst[MAX_PKT_BURST];
-	struct virtio_net_data_ll *dev_ll;
-	struct mbuf_table *tx_q;
-	volatile struct lcore_ll_info *lcore_ll;
-	const uint64_t drain_tsc = (rte_get_tsc_hz() + US_PER_S - 1) / US_PER_S * BURST_TX_DRAIN_US;
-	uint64_t prev_tsc, diff_tsc, cur_tsc, ret_count = 0;
-	unsigned ret, i;
-	const uint16_t lcore_id = rte_lcore_id();
-	const uint16_t num_cores = (uint16_t)rte_lcore_count();
-	uint16_t rx_count = 0;
-	uint32_t mergeable = 0;
-
-	RTE_LOG(INFO, VHOST_DATA, "Procesing on Core %u started\n", lcore_id);
-	lcore_ll = lcore_info[lcore_id].lcore_ll;
-	prev_tsc = 0;
-
-	tx_q = &lcore_tx_queue[lcore_id];
-	for (i = 0; i < num_cores; i ++) {
-		if (lcore_ids[i] == lcore_id) {
-			tx_q->txq_id = i;
-			break;
-		}
-	}
-
-	while(1) {
-		cur_tsc = rte_rdtsc();
-		/*
-		 * TX burst queue drain
-		 */
-		diff_tsc = cur_tsc - prev_tsc;
-		if (unlikely(diff_tsc > drain_tsc)) {
-
-			if (tx_q->len) {
-				LOG_DEBUG(VHOST_DATA, "TX queue drained after timeout with burst size %u \n", tx_q->len);
-
-				/*Tx any packets in the queue*/
-				ret = rte_eth_tx_burst(ports[0], (uint16_t)tx_q->txq_id,
-									   (struct rte_mbuf **)tx_q->m_table,
-									   (uint16_t)tx_q->len);
-				if (unlikely(ret < tx_q->len)) {
-					do {
-						rte_pktmbuf_free(tx_q->m_table[ret]);
-					} while (++ret < tx_q->len);
-				}
-
-				tx_q->len = 0;
-			}
-
-			prev_tsc = cur_tsc;
-
-		}
-
-		rte_prefetch0(lcore_ll->ll_root_used);
-		/*
-		 * Inform the configuration core that we have exited the linked list and that no devices are
-		 * in use if requested.
-		 */
-		if (lcore_ll->dev_removal_flag == REQUEST_DEV_REMOVAL)
-			lcore_ll->dev_removal_flag = ACK_DEV_REMOVAL;
-
-		/*
-		 * Process devices
-		 */
-		dev_ll = lcore_ll->ll_root_used;
-
-		while (dev_ll != NULL) {
-			/*get virtio device ID*/
-			dev = dev_ll->dev;
-			mergeable =
-				dev->features & (1 << VIRTIO_NET_F_MRG_RXBUF);
-
-			if (dev->remove) {
-				dev_ll = dev_ll->next;
-				unlink_vmdq(dev);
-				dev->ready = DEVICE_SAFE_REMOVE;
-				continue;
-			}
-			if (likely(dev->ready == DEVICE_RX)) {
-				/*Handle guest RX*/
-				rx_count = rte_eth_rx_burst(ports[0],
-					(uint16_t)dev->vmdq_rx_q, pkts_burst, MAX_PKT_BURST);
-
-				if (rx_count) {
-					if (likely(mergeable == 0))
-						ret_count =
-							virtio_dev_rx(dev,
-							pkts_burst, rx_count);
-					else
-						ret_count =
-							virtio_dev_merge_rx(dev,
-							pkts_burst, rx_count);
-
-					if (enable_stats) {
-						rte_atomic64_add(
-						&dev_statistics[dev_ll->dev->device_fh].rx_total_atomic,
-						rx_count);
-						rte_atomic64_add(
-						&dev_statistics[dev_ll->dev->device_fh].rx_atomic, ret_count);
-					}
-					while (likely(rx_count)) {
-						rx_count--;
-						rte_pktmbuf_free(pkts_burst[rx_count]);
-					}
-
-				}
-			}
-
-			if (!dev->remove) {
-				/*Handle guest TX*/
-				if (likely(mergeable == 0))
-					virtio_dev_tx(dev, mbuf_pool);
-				else
-					virtio_dev_merge_tx(dev, mbuf_pool);
-			}
-
-			/*move to the next device in the list*/
-			dev_ll = dev_ll->next;
-		}
-	}
-
-	return 0;
-}
-
-/*
- * This function gets available ring number for zero copy rx.
- * Only one thread will call this funciton for a paticular virtio device,
- * so, it is designed as non-thread-safe function.
- */
-static inline uint32_t __attribute__((always_inline))
-get_available_ring_num_zcp(struct virtio_net *dev)
-{
-	struct vhost_virtqueue *vq = dev->virtqueue[VIRTIO_RXQ];
-	uint16_t avail_idx;
-
-	avail_idx = *((volatile uint16_t *)&vq->avail->idx);
-	return (uint32_t)(avail_idx - vq->last_used_idx_res);
-}
-
-/*
- * This function gets available ring index for zero copy rx,
- * it will retry 'burst_rx_retry_num' times till it get enough ring index.
- * Only one thread will call this funciton for a paticular virtio device,
- * so, it is designed as non-thread-safe function.
- */
-static inline uint32_t __attribute__((always_inline))
-get_available_ring_index_zcp(struct virtio_net *dev,
-	uint16_t *res_base_idx, uint32_t count)
-{
-	struct vhost_virtqueue *vq = dev->virtqueue[VIRTIO_RXQ];
-	uint16_t avail_idx;
-	uint32_t retry = 0;
-	uint16_t free_entries;
-
-	*res_base_idx = vq->last_used_idx_res;
-	avail_idx = *((volatile uint16_t *)&vq->avail->idx);
-	free_entries = (avail_idx - *res_base_idx);
-
-	LOG_DEBUG(VHOST_DATA, "(%"PRIu64") in get_available_ring_index_zcp: "
-			"avail idx: %d, "
-			"res base idx:%d, free entries:%d\n",
-			dev->device_fh, avail_idx, *res_base_idx,
-			free_entries);
-
-	/*
-	 * If retry is enabled and the queue is full then we wait
-	 * and retry to avoid packet loss.
-	 */
-	if (enable_retry && unlikely(count > free_entries)) {
-		for (retry = 0; retry < burst_rx_retry_num; retry++) {
-			rte_delay_us(burst_rx_delay_time);
-			avail_idx = *((volatile uint16_t *)&vq->avail->idx);
-			free_entries = (avail_idx - *res_base_idx);
-			if (count <= free_entries)
-				break;
-		}
-	}
-
-	/*check that we have enough buffers*/
-	if (unlikely(count > free_entries))
-		count = free_entries;
-
-	if (unlikely(count == 0)) {
-		LOG_DEBUG(VHOST_DATA,
-			"(%"PRIu64") Fail in get_available_ring_index_zcp: "
-			"avail idx: %d, res base idx:%d, free entries:%d\n",
-			dev->device_fh, avail_idx,
-			*res_base_idx, free_entries);
-		return 0;
-	}
-
-	vq->last_used_idx_res = *res_base_idx + count;
-
-	return count;
-}
-
-/*
- * This function put descriptor back to used list.
- */
-static inline void __attribute__((always_inline))
-put_desc_to_used_list_zcp(struct vhost_virtqueue *vq, uint16_t desc_idx)
-{
-	uint16_t res_cur_idx = vq->last_used_idx;
-	vq->used->ring[res_cur_idx & (vq->size - 1)].id = (uint32_t)desc_idx;
-	vq->used->ring[res_cur_idx & (vq->size - 1)].len = 0;
-	rte_compiler_barrier();
-	*(volatile uint16_t *)&vq->used->idx += 1;
-	vq->last_used_idx += 1;
-
-	/* Kick the guest if necessary. */
-	if (!(vq->avail->flags & VRING_AVAIL_F_NO_INTERRUPT))
-		eventfd_write((int)vq->kickfd, 1);
-}
-
-/*
- * This function get available descriptor from vitio vring and un-attached mbuf
- * from vpool->ring, and then attach them together. It needs adjust the offset
- * for buff_addr and phys_addr accroding to PMD implementation, otherwise the
- * frame data may be put to wrong location in mbuf.
- */
-static inline void __attribute__((always_inline))
-attach_rxmbuf_zcp(struct virtio_net *dev)
-{
-	uint16_t res_base_idx, desc_idx;
-	uint64_t buff_addr, phys_addr;
-	struct vhost_virtqueue *vq;
-	struct vring_desc *desc;
-	struct rte_mbuf *mbuf = NULL;
-	struct vpool *vpool;
-	hpa_type addr_type;
-
-	vpool = &vpool_array[dev->vmdq_rx_q];
-	vq = dev->virtqueue[VIRTIO_RXQ];
-
-	do {
-		if (unlikely(get_available_ring_index_zcp(dev, &res_base_idx,
-				1) != 1))
-			return;
-		desc_idx = vq->avail->ring[(res_base_idx) & (vq->size - 1)];
-
-		desc = &vq->desc[desc_idx];
-		if (desc->flags & VRING_DESC_F_NEXT) {
-			desc = &vq->desc[desc->next];
-			buff_addr = gpa_to_vva(dev, desc->addr);
-			phys_addr = gpa_to_hpa(dev, desc->addr, desc->len,
-					&addr_type);
-		} else {
-			buff_addr = gpa_to_vva(dev,
-					desc->addr + vq->vhost_hlen);
-			phys_addr = gpa_to_hpa(dev,
-					desc->addr + vq->vhost_hlen,
-					desc->len, &addr_type);
-		}
-
-		if (unlikely(addr_type == PHYS_ADDR_INVALID)) {
-			RTE_LOG(ERR, VHOST_DATA, "(%"PRIu64") Invalid frame buffer"
-				" address found when attaching RX frame buffer"
-				" address!\n", dev->device_fh);
-			put_desc_to_used_list_zcp(vq, desc_idx);
-			continue;
-		}
-
-		/*
-		 * Check if the frame buffer address from guest crosses
-		 * sub-region or not.
-		 */
-		if (unlikely(addr_type == PHYS_ADDR_CROSS_SUBREG)) {
-			RTE_LOG(ERR, VHOST_DATA,
-				"(%"PRIu64") Frame buffer address cross "
-				"sub-regioin found when attaching RX frame "
-				"buffer address!\n",
-				dev->device_fh);
-			put_desc_to_used_list_zcp(vq, desc_idx);
-			continue;
-		}
-	} while (unlikely(phys_addr == 0));
-
-	rte_ring_sc_dequeue(vpool->ring, (void **)&mbuf);
-	if (unlikely(mbuf == NULL)) {
-		LOG_DEBUG(VHOST_DATA,
-			"(%"PRIu64") in attach_rxmbuf_zcp: "
-			"ring_sc_dequeue fail.\n",
-			dev->device_fh);
-		put_desc_to_used_list_zcp(vq, desc_idx);
-		return;
-	}
-
-	if (unlikely(vpool->buf_size > desc->len)) {
-		LOG_DEBUG(VHOST_DATA,
-			"(%"PRIu64") in attach_rxmbuf_zcp: frame buffer "
-			"length(%d) of descriptor idx: %d less than room "
-			"size required: %d\n",
-			dev->device_fh, desc->len, desc_idx, vpool->buf_size);
-		put_desc_to_used_list_zcp(vq, desc_idx);
-		rte_ring_sp_enqueue(vpool->ring, (void *)mbuf);
-		return;
-	}
-
-	mbuf->buf_addr = (void *)(uintptr_t)(buff_addr - RTE_PKTMBUF_HEADROOM);
-	mbuf->data_off = RTE_PKTMBUF_HEADROOM;
-	mbuf->buf_physaddr = phys_addr - RTE_PKTMBUF_HEADROOM;
-	mbuf->data_len = desc->len;
-	MBUF_HEADROOM_UINT32(mbuf) = (uint32_t)desc_idx;
-
-	LOG_DEBUG(VHOST_DATA,
-		"(%"PRIu64") in attach_rxmbuf_zcp: res base idx:%d, "
-		"descriptor idx:%d\n",
-		dev->device_fh, res_base_idx, desc_idx);
-
-	__rte_mbuf_raw_free(mbuf);
-
-	return;
-}
-
-/*
- * Detach an attched packet mbuf -
- *  - restore original mbuf address and length values.
- *  - reset pktmbuf data and data_len to their default values.
- *  All other fields of the given packet mbuf will be left intact.
- *
- * @param m
- *   The attached packet mbuf.
- */
-static inline void pktmbuf_detach_zcp(struct rte_mbuf *m)
-{
-	const struct rte_mempool *mp = m->pool;
-	void *buf = RTE_MBUF_TO_BADDR(m);
-	uint32_t buf_ofs;
-	uint32_t buf_len = mp->elt_size - sizeof(*m);
-	m->buf_physaddr = rte_mempool_virt2phy(mp, m) + sizeof(*m);
-
-	m->buf_addr = buf;
-	m->buf_len = (uint16_t)buf_len;
-
-	buf_ofs = (RTE_PKTMBUF_HEADROOM <= m->buf_len) ?
-			RTE_PKTMBUF_HEADROOM : m->buf_len;
-	m->data_off = buf_ofs;
-
-	m->data_len = 0;
-}
-
-/*
- * This function is called after packets have been transimited. It fetchs mbuf
- * from vpool->pool, detached it and put into vpool->ring. It also update the
- * used index and kick the guest if necessary.
- */
-static inline uint32_t __attribute__((always_inline))
-txmbuf_clean_zcp(struct virtio_net *dev, struct vpool *vpool)
-{
-	struct rte_mbuf *mbuf;
-	struct vhost_virtqueue *vq = dev->virtqueue[VIRTIO_TXQ];
-	uint32_t used_idx = vq->last_used_idx & (vq->size - 1);
-	uint32_t index = 0;
-	uint32_t mbuf_count = rte_mempool_count(vpool->pool);
-
-	LOG_DEBUG(VHOST_DATA,
-		"(%"PRIu64") in txmbuf_clean_zcp: mbuf count in mempool before "
-		"clean is: %d\n",
-		dev->device_fh, mbuf_count);
-	LOG_DEBUG(VHOST_DATA,
-		"(%"PRIu64") in txmbuf_clean_zcp: mbuf count in  ring before "
-		"clean  is : %d\n",
-		dev->device_fh, rte_ring_count(vpool->ring));
-
-	for (index = 0; index < mbuf_count; index++) {
-		mbuf = __rte_mbuf_raw_alloc(vpool->pool);
-		if (likely(RTE_MBUF_INDIRECT(mbuf)))
-			pktmbuf_detach_zcp(mbuf);
-		rte_ring_sp_enqueue(vpool->ring, mbuf);
-
-		/* Update used index buffer information. */
-		vq->used->ring[used_idx].id = MBUF_HEADROOM_UINT32(mbuf);
-		vq->used->ring[used_idx].len = 0;
-
-		used_idx = (used_idx + 1) & (vq->size - 1);
-	}
-
-	LOG_DEBUG(VHOST_DATA,
-		"(%"PRIu64") in txmbuf_clean_zcp: mbuf count in mempool after "
-		"clean is: %d\n",
-		dev->device_fh, rte_mempool_count(vpool->pool));
-	LOG_DEBUG(VHOST_DATA,
-		"(%"PRIu64") in txmbuf_clean_zcp: mbuf count in  ring after "
-		"clean  is : %d\n",
-		dev->device_fh, rte_ring_count(vpool->ring));
-	LOG_DEBUG(VHOST_DATA,
-		"(%"PRIu64") in txmbuf_clean_zcp: before updated "
-		"vq->last_used_idx:%d\n",
-		dev->device_fh, vq->last_used_idx);
-
-	vq->last_used_idx += mbuf_count;
-
-	LOG_DEBUG(VHOST_DATA,
-		"(%"PRIu64") in txmbuf_clean_zcp: after updated "
-		"vq->last_used_idx:%d\n",
-		dev->device_fh, vq->last_used_idx);
-
-	rte_compiler_barrier();
-
-	*(volatile uint16_t *)&vq->used->idx += mbuf_count;
-
-	/* Kick guest if required. */
-	if (!(vq->avail->flags & VRING_AVAIL_F_NO_INTERRUPT))
-		eventfd_write((int)vq->kickfd, 1);
-
-	return 0;
-}
-
-/*
- * This function is called when a virtio device is destroy.
- * It fetchs mbuf from vpool->pool, and detached it, and put into vpool->ring.
- */
-static void mbuf_destroy_zcp(struct vpool *vpool)
-{
-	struct rte_mbuf *mbuf = NULL;
-	uint32_t index, mbuf_count = rte_mempool_count(vpool->pool);
-
-	LOG_DEBUG(VHOST_CONFIG,
-		"in mbuf_destroy_zcp: mbuf count in mempool before "
-		"mbuf_destroy_zcp is: %d\n",
-		mbuf_count);
-	LOG_DEBUG(VHOST_CONFIG,
-		"in mbuf_destroy_zcp: mbuf count in  ring before "
-		"mbuf_destroy_zcp  is : %d\n",
-		rte_ring_count(vpool->ring));
-
-	for (index = 0; index < mbuf_count; index++) {
-		mbuf = __rte_mbuf_raw_alloc(vpool->pool);
-		if (likely(mbuf != NULL)) {
-			if (likely(RTE_MBUF_INDIRECT(mbuf)))
-				pktmbuf_detach_zcp(mbuf);
-			rte_ring_sp_enqueue(vpool->ring, (void *)mbuf);
-		}
-	}
-
-	LOG_DEBUG(VHOST_CONFIG,
-		"in mbuf_destroy_zcp: mbuf count in mempool after "
-		"mbuf_destroy_zcp is: %d\n",
-		rte_mempool_count(vpool->pool));
-	LOG_DEBUG(VHOST_CONFIG,
-		"in mbuf_destroy_zcp: mbuf count in ring after "
-		"mbuf_destroy_zcp is : %d\n",
-		rte_ring_count(vpool->ring));
-}
-
-/*
- * This function update the use flag and counter.
- */
-static inline uint32_t __attribute__((always_inline))
-virtio_dev_rx_zcp(struct virtio_net *dev, struct rte_mbuf **pkts,
-	uint32_t count)
-{
-	struct vhost_virtqueue *vq;
-	struct vring_desc *desc;
-	struct rte_mbuf *buff;
-	/* The virtio_hdr is initialised to 0. */
-	struct virtio_net_hdr_mrg_rxbuf virtio_hdr
-		= {{0, 0, 0, 0, 0, 0}, 0};
-	uint64_t buff_hdr_addr = 0;
-	uint32_t head[MAX_PKT_BURST], packet_len = 0;
-	uint32_t head_idx, packet_success = 0;
-	uint16_t res_cur_idx;
-
-	LOG_DEBUG(VHOST_DATA, "(%"PRIu64") virtio_dev_rx()\n", dev->device_fh);
-
-	if (count == 0)
-		return 0;
-
-	vq = dev->virtqueue[VIRTIO_RXQ];
-	count = (count > MAX_PKT_BURST) ? MAX_PKT_BURST : count;
-
-	res_cur_idx = vq->last_used_idx;
-	LOG_DEBUG(VHOST_DATA, "(%"PRIu64") Current Index %d| End Index %d\n",
-		dev->device_fh, res_cur_idx, res_cur_idx + count);
-
-	/* Retrieve all of the head indexes first to avoid caching issues. */
-	for (head_idx = 0; head_idx < count; head_idx++)
-		head[head_idx] = MBUF_HEADROOM_UINT32(pkts[head_idx]);
-
-	/*Prefetch descriptor index. */
-	rte_prefetch0(&vq->desc[head[packet_success]]);
-
-	while (packet_success != count) {
-		/* Get descriptor from available ring */
-		desc = &vq->desc[head[packet_success]];
-
-		buff = pkts[packet_success];
-		LOG_DEBUG(VHOST_DATA,
-			"(%"PRIu64") in dev_rx_zcp: update the used idx for "
-			"pkt[%d] descriptor idx: %d\n",
-			dev->device_fh, packet_success,
-			MBUF_HEADROOM_UINT32(buff));
-
-		PRINT_PACKET(dev,
-			(uintptr_t)(((uint64_t)(uintptr_t)buff->buf_addr)
-			+ RTE_PKTMBUF_HEADROOM),
-			rte_pktmbuf_data_len(buff), 0);
-
-		/* Buffer address translation for virtio header. */
-		buff_hdr_addr = gpa_to_vva(dev, desc->addr);
-		packet_len = rte_pktmbuf_data_len(buff) + vq->vhost_hlen;
-
-		/*
-		 * If the descriptors are chained the header and data are
-		 * placed in separate buffers.
-		 */
-		if (desc->flags & VRING_DESC_F_NEXT) {
-			desc->len = vq->vhost_hlen;
-			desc = &vq->desc[desc->next];
-			desc->len = rte_pktmbuf_data_len(buff);
-		} else {
-			desc->len = packet_len;
-		}
-
-		/* Update used ring with desc information */
-		vq->used->ring[res_cur_idx & (vq->size - 1)].id
-			= head[packet_success];
-		vq->used->ring[res_cur_idx & (vq->size - 1)].len
-			= packet_len;
-		res_cur_idx++;
-		packet_success++;
-
-		/* A header is required per buffer. */
-		rte_memcpy((void *)(uintptr_t)buff_hdr_addr,
-			(const void *)&virtio_hdr, vq->vhost_hlen);
-
-		PRINT_PACKET(dev, (uintptr_t)buff_hdr_addr, vq->vhost_hlen, 1);
-
-		if (likely(packet_success < count)) {
-			/* Prefetch descriptor index. */
-			rte_prefetch0(&vq->desc[head[packet_success]]);
-		}
-	}
-
-	rte_compiler_barrier();
-
-	LOG_DEBUG(VHOST_DATA,
-		"(%"PRIu64") in dev_rx_zcp: before update used idx: "
-		"vq.last_used_idx: %d, vq->used->idx: %d\n",
-		dev->device_fh, vq->last_used_idx, vq->used->idx);
-
-	*(volatile uint16_t *)&vq->used->idx += count;
-	vq->last_used_idx += count;
-
-	LOG_DEBUG(VHOST_DATA,
-		"(%"PRIu64") in dev_rx_zcp: after  update used idx: "
-		"vq.last_used_idx: %d, vq->used->idx: %d\n",
-		dev->device_fh, vq->last_used_idx, vq->used->idx);
-
-	/* Kick the guest if necessary. */
-	if (!(vq->avail->flags & VRING_AVAIL_F_NO_INTERRUPT))
-		eventfd_write((int)vq->kickfd, 1);
-
-	return count;
-}
-
-/*
- * This function routes the TX packet to the correct interface.
- * This may be a local device or the physical port.
- */
-static inline void __attribute__((always_inline))
-virtio_tx_route_zcp(struct virtio_net *dev, struct rte_mbuf *m,
-	uint32_t desc_idx, uint8_t need_copy)
-{
-	struct mbuf_table *tx_q;
-	struct rte_mbuf **m_table;
-	struct rte_mbuf *mbuf = NULL;
-	unsigned len, ret, offset = 0;
-	struct vpool *vpool;
-	struct virtio_net_data_ll *dev_ll = ll_root_used;
-	struct ether_hdr *pkt_hdr = rte_pktmbuf_mtod(m, struct ether_hdr *);
-	uint16_t vlan_tag = (uint16_t)vlan_tags[(uint16_t)dev->device_fh];
-
-	/*Add packet to the port tx queue*/
-	tx_q = &tx_queue_zcp[(uint16_t)dev->vmdq_rx_q];
-	len = tx_q->len;
-
-	/* Allocate an mbuf and populate the structure. */
-	vpool = &vpool_array[MAX_QUEUES + (uint16_t)dev->vmdq_rx_q];
-	rte_ring_sc_dequeue(vpool->ring, (void **)&mbuf);
-	if (unlikely(mbuf == NULL)) {
-		struct vhost_virtqueue *vq = dev->virtqueue[VIRTIO_TXQ];
-		RTE_LOG(ERR, VHOST_DATA,
-			"(%"PRIu64") Failed to allocate memory for mbuf.\n",
-			dev->device_fh);
-		put_desc_to_used_list_zcp(vq, desc_idx);
-		return;
-	}
-
-	if (vm2vm_mode == VM2VM_HARDWARE) {
-		/* Avoid using a vlan tag from any vm for external pkt, such as
-		 * vlan_tags[dev->device_fh], oterwise, it conflicts when pool
-		 * selection, MAC address determines it as an external pkt
-		 * which should go to network, while vlan tag determine it as
-		 * a vm2vm pkt should forward to another vm. Hardware confuse
-		 * such a ambiguous situation, so pkt will lost.
-		 */
-		vlan_tag = external_pkt_default_vlan_tag;
-		while (dev_ll != NULL) {
-			if (likely(dev_ll->dev->ready == DEVICE_RX) &&
-				ether_addr_cmp(&(pkt_hdr->d_addr),
-				&dev_ll->dev->mac_address)) {
-
-				/*
-				 * Drop the packet if the TX packet is destined
-				 * for the TX device.
-				 */
-				if (unlikely(dev_ll->dev->device_fh
-					== dev->device_fh)) {
-					LOG_DEBUG(VHOST_DATA,
-					"(%"PRIu64") TX: Source and destination"
-					"MAC addresses are the same. Dropping "
-					"packet.\n",
-					dev_ll->dev->device_fh);
-					MBUF_HEADROOM_UINT32(mbuf)
-						= (uint32_t)desc_idx;
-					__rte_mbuf_raw_free(mbuf);
-					return;
-				}
-
-				/*
-				 * Packet length offset 4 bytes for HW vlan
-				 * strip when L2 switch back.
-				 */
-				offset = 4;
-				vlan_tag =
-				(uint16_t)
-				vlan_tags[(uint16_t)dev_ll->dev->device_fh];
-
-				LOG_DEBUG(VHOST_DATA,
-				"(%"PRIu64") TX: pkt to local VM device id:"
-				"(%"PRIu64") vlan tag: %d.\n",
-				dev->device_fh, dev_ll->dev->device_fh,
-				vlan_tag);
-
-				break;
-			}
-			dev_ll = dev_ll->next;
-		}
-	}
-
-	mbuf->nb_segs = m->nb_segs;
-	mbuf->next = m->next;
-	mbuf->data_len = m->data_len + offset;
-	mbuf->pkt_len = mbuf->data_len;
-	if (unlikely(need_copy)) {
-		/* Copy the packet contents to the mbuf. */
-		rte_memcpy(rte_pktmbuf_mtod(mbuf, void *),
-			rte_pktmbuf_mtod(m, void *),
-			m->data_len);
-	} else {
-		mbuf->data_off = m->data_off;
-		mbuf->buf_physaddr = m->buf_physaddr;
-		mbuf->buf_addr = m->buf_addr;
-	}
-	mbuf->ol_flags = PKT_TX_VLAN_PKT;
-	mbuf->vlan_tci = vlan_tag;
-	mbuf->l2_len = sizeof(struct ether_hdr);
-	mbuf->l3_len = sizeof(struct ipv4_hdr);
-	MBUF_HEADROOM_UINT32(mbuf) = (uint32_t)desc_idx;
-
-	tx_q->m_table[len] = mbuf;
-	len++;
-
-	LOG_DEBUG(VHOST_DATA,
-		"(%"PRIu64") in tx_route_zcp: pkt: nb_seg: %d, next:%s\n",
-		dev->device_fh,
-		mbuf->nb_segs,
-		(mbuf->next == NULL) ? "null" : "non-null");
-
-	if (enable_stats) {
-		dev_statistics[dev->device_fh].tx_total++;
-		dev_statistics[dev->device_fh].tx++;
-	}
-
-	if (unlikely(len == MAX_PKT_BURST)) {
-		m_table = (struct rte_mbuf **)tx_q->m_table;
-		ret = rte_eth_tx_burst(ports[0],
-			(uint16_t)tx_q->txq_id, m_table, (uint16_t) len);
-
-		/*
-		 * Free any buffers not handled by TX and update
-		 * the port stats.
-		 */
-		if (unlikely(ret < len)) {
-			do {
-				rte_pktmbuf_free(m_table[ret]);
-			} while (++ret < len);
-		}
-
-		len = 0;
-		txmbuf_clean_zcp(dev, vpool);
-	}
-
-	tx_q->len = len;
-
-	return;
-}
-
-/*
- * This function TX all available packets in virtio TX queue for one
- * virtio-net device. If it is first packet, it learns MAC address and
- * setup VMDQ.
- */
-static inline void __attribute__((always_inline))
-virtio_dev_tx_zcp(struct virtio_net *dev)
-{
-	struct rte_mbuf m;
-	struct vhost_virtqueue *vq;
-	struct vring_desc *desc;
-	uint64_t buff_addr = 0, phys_addr;
-	uint32_t head[MAX_PKT_BURST];
-	uint32_t i;
-	uint16_t free_entries, packet_success = 0;
-	uint16_t avail_idx;
-	uint8_t need_copy = 0;
-	hpa_type addr_type;
-
-	vq = dev->virtqueue[VIRTIO_TXQ];
-	avail_idx =  *((volatile uint16_t *)&vq->avail->idx);
-
-	/* If there are no available buffers then return. */
-	if (vq->last_used_idx_res == avail_idx)
-		return;
-
-	LOG_DEBUG(VHOST_DATA, "(%"PRIu64") virtio_dev_tx()\n", dev->device_fh);
-
-	/* Prefetch available ring to retrieve head indexes. */
-	rte_prefetch0(&vq->avail->ring[vq->last_used_idx_res & (vq->size - 1)]);
-
-	/* Get the number of free entries in the ring */
-	free_entries = (avail_idx - vq->last_used_idx_res);
-
-	/* Limit to MAX_PKT_BURST. */
-	free_entries
-		= (free_entries > MAX_PKT_BURST) ? MAX_PKT_BURST : free_entries;
-
-	LOG_DEBUG(VHOST_DATA, "(%"PRIu64") Buffers available %d\n",
-		dev->device_fh, free_entries);
-
-	/* Retrieve all of the head indexes first to avoid caching issues. */
-	for (i = 0; i < free_entries; i++)
-		head[i]
-			= vq->avail->ring[(vq->last_used_idx_res + i)
-			& (vq->size - 1)];
-
-	vq->last_used_idx_res += free_entries;
-
-	/* Prefetch descriptor index. */
-	rte_prefetch0(&vq->desc[head[packet_success]]);
-	rte_prefetch0(&vq->used->ring[vq->last_used_idx & (vq->size - 1)]);
-
-	while (packet_success < free_entries) {
-		desc = &vq->desc[head[packet_success]];
-
-		/* Discard first buffer as it is the virtio header */
-		desc = &vq->desc[desc->next];
-
-		/* Buffer address translation. */
-		buff_addr = gpa_to_vva(dev, desc->addr);
-		phys_addr = gpa_to_hpa(dev, desc->addr, desc->len, &addr_type);
-
-		if (likely(packet_success < (free_entries - 1)))
-			/* Prefetch descriptor index. */
-			rte_prefetch0(&vq->desc[head[packet_success + 1]]);
-
-		if (unlikely(addr_type == PHYS_ADDR_INVALID)) {
-			RTE_LOG(ERR, VHOST_DATA,
-				"(%"PRIu64") Invalid frame buffer address found"
-				"when TX packets!\n",
-				dev->device_fh);
-			packet_success++;
-			continue;
-		}
-
-		/* Prefetch buffer address. */
-		rte_prefetch0((void *)(uintptr_t)buff_addr);
-
-		/*
-		 * Setup dummy mbuf. This is copied to a real mbuf if
-		 * transmitted out the physical port.
-		 */
-		m.data_len = desc->len;
-		m.nb_segs = 1;
-		m.next = NULL;
-		m.data_off = 0;
-		m.buf_addr = (void *)(uintptr_t)buff_addr;
-		m.buf_physaddr = phys_addr;
-
-		/*
-		 * Check if the frame buffer address from guest crosses
-		 * sub-region or not.
-		 */
-		if (unlikely(addr_type == PHYS_ADDR_CROSS_SUBREG)) {
-			RTE_LOG(ERR, VHOST_DATA,
-				"(%"PRIu64") Frame buffer address cross "
-				"sub-regioin found when attaching TX frame "
-				"buffer address!\n",
-				dev->device_fh);
-			need_copy = 1;
-		} else
-			need_copy = 0;
-
-		PRINT_PACKET(dev, (uintptr_t)buff_addr, desc->len, 0);
-
-		/*
-		 * If this is the first received packet we need to learn
-		 * the MAC and setup VMDQ
-		 */
-		if (unlikely(dev->ready == DEVICE_MAC_LEARNING)) {
-			if (dev->remove || (link_vmdq(dev, &m) == -1)) {
-				/*
-				 * Discard frame if device is scheduled for
-				 * removal or a duplicate MAC address is found.
-				 */
-				packet_success += free_entries;
-				vq->last_used_idx += packet_success;
-				break;
-			}
-		}
-
-		virtio_tx_route_zcp(dev, &m, head[packet_success], need_copy);
-		packet_success++;
-	}
-}
-
-/*
- * This function is called by each data core. It handles all RX/TX registered
- * with the core. For TX the specific lcore linked list is used. For RX, MAC
- * addresses are compared with all devices in the main linked list.
- */
-static int
-switch_worker_zcp(__attribute__((unused)) void *arg)
-{
-	struct virtio_net *dev = NULL;
-	struct rte_mbuf *pkts_burst[MAX_PKT_BURST];
-	struct virtio_net_data_ll *dev_ll;
-	struct mbuf_table *tx_q;
-	volatile struct lcore_ll_info *lcore_ll;
-	const uint64_t drain_tsc
-		= (rte_get_tsc_hz() + US_PER_S - 1) / US_PER_S
-		* BURST_TX_DRAIN_US;
-	uint64_t prev_tsc, diff_tsc, cur_tsc, ret_count = 0;
-	unsigned ret;
-	const uint16_t lcore_id = rte_lcore_id();
-	uint16_t count_in_ring, rx_count = 0;
-
-	RTE_LOG(INFO, VHOST_DATA, "Procesing on Core %u started\n", lcore_id);
-
-	lcore_ll = lcore_info[lcore_id].lcore_ll;
-	prev_tsc = 0;
-
-	while (1) {
-		cur_tsc = rte_rdtsc();
-
-		/* TX burst queue drain */
-		diff_tsc = cur_tsc - prev_tsc;
-		if (unlikely(diff_tsc > drain_tsc)) {
-			/*
-			 * Get mbuf from vpool.pool and detach mbuf and
-			 * put back into vpool.ring.
-			 */
-			dev_ll = lcore_ll->ll_root_used;
-			while ((dev_ll != NULL) && (dev_ll->dev != NULL)) {
-				/* Get virtio device ID */
-				dev = dev_ll->dev;
-
-				if (likely(!dev->remove)) {
-					tx_q = &tx_queue_zcp[(uint16_t)dev->vmdq_rx_q];
-					if (tx_q->len) {
-						LOG_DEBUG(VHOST_DATA,
-						"TX queue drained after timeout"
-						" with burst size %u\n",
-						tx_q->len);
-
-						/*
-						 * Tx any packets in the queue
-						 */
-						ret = rte_eth_tx_burst(
-							ports[0],
-							(uint16_t)tx_q->txq_id,
-							(struct rte_mbuf **)
-							tx_q->m_table,
-							(uint16_t)tx_q->len);
-						if (unlikely(ret < tx_q->len)) {
-							do {
-								rte_pktmbuf_free(
-									tx_q->m_table[ret]);
-							} while (++ret < tx_q->len);
-						}
-						tx_q->len = 0;
-
-						txmbuf_clean_zcp(dev,
-							&vpool_array[MAX_QUEUES+dev->vmdq_rx_q]);
-					}
-				}
-				dev_ll = dev_ll->next;
-			}
-			prev_tsc = cur_tsc;
-		}
-
-		rte_prefetch0(lcore_ll->ll_root_used);
-
-		/*
-		 * Inform the configuration core that we have exited the linked
-		 * list and that no devices are in use if requested.
-		 */
-		if (lcore_ll->dev_removal_flag == REQUEST_DEV_REMOVAL)
-			lcore_ll->dev_removal_flag = ACK_DEV_REMOVAL;
-
-		/* Process devices */
-		dev_ll = lcore_ll->ll_root_used;
-
-		while ((dev_ll != NULL) && (dev_ll->dev != NULL)) {
-			dev = dev_ll->dev;
-			if (unlikely(dev->remove)) {
-				dev_ll = dev_ll->next;
-				unlink_vmdq(dev);
-				dev->ready = DEVICE_SAFE_REMOVE;
-				continue;
-			}
-
-			if (likely(dev->ready == DEVICE_RX)) {
-				uint32_t index = dev->vmdq_rx_q;
-				uint16_t i;
-				count_in_ring
-				= rte_ring_count(vpool_array[index].ring);
-				uint16_t free_entries
-				= (uint16_t)get_available_ring_num_zcp(dev);
-
-				/*
-				 * Attach all mbufs in vpool.ring and put back
-				 * into vpool.pool.
-				 */
-				for (i = 0;
-				i < RTE_MIN(free_entries,
-				RTE_MIN(count_in_ring, MAX_PKT_BURST));
-				i++)
-					attach_rxmbuf_zcp(dev);
-
-				/* Handle guest RX */
-				rx_count = rte_eth_rx_burst(ports[0],
-					(uint16_t)dev->vmdq_rx_q, pkts_burst,
-					MAX_PKT_BURST);
-
-				if (rx_count) {
-					ret_count = virtio_dev_rx_zcp(dev,
-							pkts_burst, rx_count);
-					if (enable_stats) {
-						dev_statistics[dev->device_fh].rx_total
-							+= rx_count;
-						dev_statistics[dev->device_fh].rx
-							+= ret_count;
-					}
-					while (likely(rx_count)) {
-						rx_count--;
-						pktmbuf_detach_zcp(
-							pkts_burst[rx_count]);
-						rte_ring_sp_enqueue(
-							vpool_array[index].ring,
-							(void *)pkts_burst[rx_count]);
-					}
-				}
-			}
-
-			if (likely(!dev->remove))
-				/* Handle guest TX */
-				virtio_dev_tx_zcp(dev);
-
-			/* Move to the next device in the list */
-			dev_ll = dev_ll->next;
-		}
-	}
-
-	return 0;
-}
-
-
-/*
- * Add an entry to a used linked list. A free entry must first be found
- * in the free linked list using get_data_ll_free_entry();
- */
-static void
-add_data_ll_entry(struct virtio_net_data_ll **ll_root_addr,
-	struct virtio_net_data_ll *ll_dev)
-{
-	struct virtio_net_data_ll *ll = *ll_root_addr;
-
-	/* Set next as NULL and use a compiler barrier to avoid reordering. */
-	ll_dev->next = NULL;
-	rte_compiler_barrier();
-
-	/* If ll == NULL then this is the first device. */
-	if (ll) {
-		/* Increment to the tail of the linked list. */
-		while ((ll->next != NULL) )
-			ll = ll->next;
-
-		ll->next = ll_dev;
-	} else {
-		*ll_root_addr = ll_dev;
-	}
-}
-
-/*
- * Remove an entry from a used linked list. The entry must then be added to
- * the free linked list using put_data_ll_free_entry().
- */
-static void
-rm_data_ll_entry(struct virtio_net_data_ll **ll_root_addr,
-	struct virtio_net_data_ll *ll_dev,
-	struct virtio_net_data_ll *ll_dev_last)
-{
-	struct virtio_net_data_ll *ll = *ll_root_addr;
-
-	if (unlikely((ll == NULL) || (ll_dev == NULL)))
-		return;
-
-	if (ll_dev == ll)
-		*ll_root_addr = ll_dev->next;
-	else
-		if (likely(ll_dev_last != NULL))
-			ll_dev_last->next = ll_dev->next;
-		else
-			RTE_LOG(ERR, VHOST_CONFIG, "Remove entry form ll failed.\n");
-}
-
-/*
- * Find and return an entry from the free linked list.
- */
-static struct virtio_net_data_ll *
-get_data_ll_free_entry(struct virtio_net_data_ll **ll_root_addr)
-{
-	struct virtio_net_data_ll *ll_free = *ll_root_addr;
-	struct virtio_net_data_ll *ll_dev;
-
-	if (ll_free == NULL)
-		return NULL;
-
-	ll_dev = ll_free;
-	*ll_root_addr = ll_free->next;
-
-	return ll_dev;
-}
-
-/*
- * Place an entry back on to the free linked list.
- */
-static void
-put_data_ll_free_entry(struct virtio_net_data_ll **ll_root_addr,
-	struct virtio_net_data_ll *ll_dev)
-{
-	struct virtio_net_data_ll *ll_free = *ll_root_addr;
-
-	if (ll_dev == NULL)
-		return;
-
-	ll_dev->next = ll_free;
-	*ll_root_addr = ll_dev;
-}
-
-/*
- * Creates a linked list of a given size.
- */
-static struct virtio_net_data_ll *
-alloc_data_ll(uint32_t size)
-{
-	struct virtio_net_data_ll *ll_new;
-	uint32_t i;
-
-	/* Malloc and then chain the linked list. */
-	ll_new = malloc(size * sizeof(struct virtio_net_data_ll));
-	if (ll_new == NULL) {
-		RTE_LOG(ERR, VHOST_CONFIG, "Failed to allocate memory for ll_new.\n");
-		return NULL;
-	}
-
-	for (i = 0; i < size - 1; i++) {
-		ll_new[i].dev = NULL;
-		ll_new[i].next = &ll_new[i+1];
-	}
-	ll_new[i].next = NULL;
-
-	return (ll_new);
-}
-
-/*
- * Create the main linked list along with each individual cores linked list. A used and a free list
- * are created to manage entries.
- */
-static int
-init_data_ll (void)
-{
-	int lcore;
-
-	RTE_LCORE_FOREACH_SLAVE(lcore) {
-		lcore_info[lcore].lcore_ll = malloc(sizeof(struct lcore_ll_info));
-		if (lcore_info[lcore].lcore_ll == NULL) {
-			RTE_LOG(ERR, VHOST_CONFIG, "Failed to allocate memory for lcore_ll.\n");
-			return -1;
-		}
-
-		lcore_info[lcore].lcore_ll->device_num = 0;
-		lcore_info[lcore].lcore_ll->dev_removal_flag = ACK_DEV_REMOVAL;
-		lcore_info[lcore].lcore_ll->ll_root_used = NULL;
-		if (num_devices % num_switching_cores)
-			lcore_info[lcore].lcore_ll->ll_root_free = alloc_data_ll((num_devices / num_switching_cores) + 1);
-		else
-			lcore_info[lcore].lcore_ll->ll_root_free = alloc_data_ll(num_devices / num_switching_cores);
-	}
-
-	/* Allocate devices up to a maximum of MAX_DEVICES. */
-	ll_root_free = alloc_data_ll(MIN((num_devices), MAX_DEVICES));
-
-	return 0;
-}
-
-/*
- * Set virtqueue flags so that we do not receive interrupts.
- */
-static void
-set_irq_status (struct virtio_net *dev)
-{
-	dev->virtqueue[VIRTIO_RXQ]->used->flags = VRING_USED_F_NO_NOTIFY;
-	dev->virtqueue[VIRTIO_TXQ]->used->flags = VRING_USED_F_NO_NOTIFY;
-}
-
-/*
- * Remove a device from the specific data core linked list and from the main linked list. Synchonization
- * occurs through the use of the lcore dev_removal_flag. Device is made volatile here to avoid re-ordering
- * of dev->remove=1 which can cause an infinite loop in the rte_pause loop.
- */
-static void
-destroy_device (volatile struct virtio_net *dev)
-{
-	struct virtio_net_data_ll *ll_lcore_dev_cur;
-	struct virtio_net_data_ll *ll_main_dev_cur;
-	struct virtio_net_data_ll *ll_lcore_dev_last = NULL;
-	struct virtio_net_data_ll *ll_main_dev_last = NULL;
-	int lcore;
-
-	dev->flags &= ~VIRTIO_DEV_RUNNING;
-
-	/*set the remove flag. */
-	dev->remove = 1;
-
-	while(dev->ready != DEVICE_SAFE_REMOVE) {
-		rte_pause();
-	}
-
-	/* Search for entry to be removed from lcore ll */
-	ll_lcore_dev_cur = lcore_info[dev->coreid].lcore_ll->ll_root_used;
-	while (ll_lcore_dev_cur != NULL) {
-		if (ll_lcore_dev_cur->dev == dev) {
-			break;
-		} else {
-			ll_lcore_dev_last = ll_lcore_dev_cur;
-			ll_lcore_dev_cur = ll_lcore_dev_cur->next;
-		}
-	}
-
-	if (ll_lcore_dev_cur == NULL) {
-		RTE_LOG(ERR, VHOST_CONFIG,
-			"(%"PRIu64") Failed to find the dev to be destroy.\n",
-			dev->device_fh);
-		return;
-	}
-
-	/* Search for entry to be removed from main ll */
-	ll_main_dev_cur = ll_root_used;
-	ll_main_dev_last = NULL;
-	while (ll_main_dev_cur != NULL) {
-		if (ll_main_dev_cur->dev == dev) {
-			break;
-		} else {
-			ll_main_dev_last = ll_main_dev_cur;
-			ll_main_dev_cur = ll_main_dev_cur->next;
-		}
-	}
-
-	/* Remove entries from the lcore and main ll. */
-	rm_data_ll_entry(&lcore_info[ll_lcore_dev_cur->dev->coreid].lcore_ll->ll_root_used, ll_lcore_dev_cur, ll_lcore_dev_last);
-	rm_data_ll_entry(&ll_root_used, ll_main_dev_cur, ll_main_dev_last);
-
-	/* Set the dev_removal_flag on each lcore. */
-	RTE_LCORE_FOREACH_SLAVE(lcore) {
-		lcore_info[lcore].lcore_ll->dev_removal_flag = REQUEST_DEV_REMOVAL;
-	}
-
-	/*
-	 * Once each core has set the dev_removal_flag to ACK_DEV_REMOVAL we can be sure that
-	 * they can no longer access the device removed from the linked lists and that the devices
-	 * are no longer in use.
-	 */
-	RTE_LCORE_FOREACH_SLAVE(lcore) {
-		while (lcore_info[lcore].lcore_ll->dev_removal_flag != ACK_DEV_REMOVAL) {
-			rte_pause();
-		}
-	}
-
-	/* Add the entries back to the lcore and main free ll.*/
-	put_data_ll_free_entry(&lcore_info[ll_lcore_dev_cur->dev->coreid].lcore_ll->ll_root_free, ll_lcore_dev_cur);
-	put_data_ll_free_entry(&ll_root_free, ll_main_dev_cur);
-
-	/* Decrement number of device on the lcore. */
-	lcore_info[ll_lcore_dev_cur->dev->coreid].lcore_ll->device_num--;
-
-	RTE_LOG(INFO, VHOST_DATA, "(%"PRIu64") Device has been removed from data core\n", dev->device_fh);
-
-	if (zero_copy) {
-		struct vpool *vpool = &vpool_array[dev->vmdq_rx_q];
-
-		/* Stop the RX queue. */
-		if (rte_eth_dev_rx_queue_stop(ports[0], dev->vmdq_rx_q) != 0) {
-			LOG_DEBUG(VHOST_CONFIG,
-				"(%"PRIu64") In destroy_device: Failed to stop "
-				"rx queue:%d\n",
-				dev->device_fh,
-				dev->vmdq_rx_q);
-		}
-
-		LOG_DEBUG(VHOST_CONFIG,
-			"(%"PRIu64") in destroy_device: Start put mbuf in "
-			"mempool back to ring for RX queue: %d\n",
-			dev->device_fh, dev->vmdq_rx_q);
-
-		mbuf_destroy_zcp(vpool);
-
-		/* Stop the TX queue. */
-		if (rte_eth_dev_tx_queue_stop(ports[0], dev->vmdq_rx_q) != 0) {
-			LOG_DEBUG(VHOST_CONFIG,
-				"(%"PRIu64") In destroy_device: Failed to "
-				"stop tx queue:%d\n",
-				dev->device_fh, dev->vmdq_rx_q);
-		}
-
-		vpool = &vpool_array[dev->vmdq_rx_q + MAX_QUEUES];
-
-		LOG_DEBUG(VHOST_CONFIG,
-			"(%"PRIu64") destroy_device: Start put mbuf in mempool "
-			"back to ring for TX queue: %d, dev:(%"PRIu64")\n",
-			dev->device_fh, (dev->vmdq_rx_q + MAX_QUEUES),
-			dev->device_fh);
-
-		mbuf_destroy_zcp(vpool);
-	}
-
-}
-
-/*
- * A new device is added to a data core. First the device is added to the main linked list
- * and the allocated to a specific data core.
- */
-static int
-new_device (struct virtio_net *dev)
-{
-	struct virtio_net_data_ll *ll_dev;
-	int lcore, core_add = 0;
-	uint32_t device_num_min = num_devices;
-
-	/* Add device to main ll */
-	ll_dev = get_data_ll_free_entry(&ll_root_free);
-	if (ll_dev == NULL) {
-		RTE_LOG(INFO, VHOST_DATA, "(%"PRIu64") No free entry found in linked list. Device limit "
-			"of %d devices per core has been reached\n",
-			dev->device_fh, num_devices);
-		return -1;
-	}
-	ll_dev->dev = dev;
-	add_data_ll_entry(&ll_root_used, ll_dev);
-	ll_dev->dev->vmdq_rx_q
-		= ll_dev->dev->device_fh * (num_queues / num_devices);
-
-	if (zero_copy) {
-		uint32_t index = ll_dev->dev->vmdq_rx_q;
-		uint32_t count_in_ring, i;
-		struct mbuf_table *tx_q;
-
-		count_in_ring = rte_ring_count(vpool_array[index].ring);
-
-		LOG_DEBUG(VHOST_CONFIG,
-			"(%"PRIu64") in new_device: mbuf count in mempool "
-			"before attach is: %d\n",
-			dev->device_fh,
-			rte_mempool_count(vpool_array[index].pool));
-		LOG_DEBUG(VHOST_CONFIG,
-			"(%"PRIu64") in new_device: mbuf count in  ring "
-			"before attach  is : %d\n",
-			dev->device_fh, count_in_ring);
-
-		/*
-		 * Attach all mbufs in vpool.ring and put back intovpool.pool.
-		 */
-		for (i = 0; i < count_in_ring; i++)
-			attach_rxmbuf_zcp(dev);
-
-		LOG_DEBUG(VHOST_CONFIG, "(%"PRIu64") in new_device: mbuf count in "
-			"mempool after attach is: %d\n",
-			dev->device_fh,
-			rte_mempool_count(vpool_array[index].pool));
-		LOG_DEBUG(VHOST_CONFIG, "(%"PRIu64") in new_device: mbuf count in "
-			"ring after attach  is : %d\n",
-			dev->device_fh,
-			rte_ring_count(vpool_array[index].ring));
-
-		tx_q = &tx_queue_zcp[(uint16_t)dev->vmdq_rx_q];
-		tx_q->txq_id = dev->vmdq_rx_q;
-
-		if (rte_eth_dev_tx_queue_start(ports[0], dev->vmdq_rx_q) != 0) {
-			struct vpool *vpool = &vpool_array[dev->vmdq_rx_q];
-
-			LOG_DEBUG(VHOST_CONFIG,
-				"(%"PRIu64") In new_device: Failed to start "
-				"tx queue:%d\n",
-				dev->device_fh, dev->vmdq_rx_q);
-
-			mbuf_destroy_zcp(vpool);
-			return -1;
-		}
-
-		if (rte_eth_dev_rx_queue_start(ports[0], dev->vmdq_rx_q) != 0) {
-			struct vpool *vpool = &vpool_array[dev->vmdq_rx_q];
-
-			LOG_DEBUG(VHOST_CONFIG,
-				"(%"PRIu64") In new_device: Failed to start "
-				"rx queue:%d\n",
-				dev->device_fh, dev->vmdq_rx_q);
-
-			/* Stop the TX queue. */
-			if (rte_eth_dev_tx_queue_stop(ports[0],
-				dev->vmdq_rx_q) != 0) {
-				LOG_DEBUG(VHOST_CONFIG,
-					"(%"PRIu64") In new_device: Failed to "
-					"stop tx queue:%d\n",
-					dev->device_fh, dev->vmdq_rx_q);
-			}
-
-			mbuf_destroy_zcp(vpool);
-			return -1;
-		}
-
-	}
-
-	/*reset ready flag*/
-	dev->ready = DEVICE_MAC_LEARNING;
-	dev->remove = 0;
-
-	/* Find a suitable lcore to add the device. */
-	RTE_LCORE_FOREACH_SLAVE(lcore) {
-		if (lcore_info[lcore].lcore_ll->device_num < device_num_min) {
-			device_num_min = lcore_info[lcore].lcore_ll->device_num;
-			core_add = lcore;
-		}
-	}
-	/* Add device to lcore ll */
-	ll_dev->dev->coreid = core_add;
-	ll_dev = get_data_ll_free_entry(&lcore_info[ll_dev->dev->coreid].lcore_ll->ll_root_free);
-	if (ll_dev == NULL) {
-		RTE_LOG(INFO, VHOST_DATA, "(%"PRIu64") Failed to add device to data core\n", dev->device_fh);
-		dev->ready = DEVICE_SAFE_REMOVE;
-		destroy_device(dev);
-		return -1;
-	}
-	ll_dev->dev = dev;
-	add_data_ll_entry(&lcore_info[ll_dev->dev->coreid].lcore_ll->ll_root_used, ll_dev);
-
-	/* Initialize device stats */
-	memset(&dev_statistics[dev->device_fh], 0, sizeof(struct device_statistics));
-
-	/* Disable notifications. */
-	set_irq_status(dev);
-	lcore_info[ll_dev->dev->coreid].lcore_ll->device_num++;
-	dev->flags |= VIRTIO_DEV_RUNNING;
-
-	RTE_LOG(INFO, VHOST_DATA, "(%"PRIu64") Device has been added to data core %d\n", dev->device_fh, dev->coreid);
-
-	return 0;
-}
-
-/*
- * These callback allow devices to be added to the data core when configuration
- * has been fully complete.
- */
-static const struct virtio_net_device_ops virtio_net_device_ops =
-{
-	.new_device =  new_device,
-	.destroy_device = destroy_device,
-};
-
-/*
- * This is a thread will wake up after a period to print stats if the user has
- * enabled them.
- */
-static void
-print_stats(void)
-{
-	struct virtio_net_data_ll *dev_ll;
-	uint64_t tx_dropped, rx_dropped;
-	uint64_t tx, tx_total, rx, rx_total;
-	uint32_t device_fh;
-	const char clr[] = { 27, '[', '2', 'J', '\0' };
-	const char top_left[] = { 27, '[', '1', ';', '1', 'H','\0' };
-
-	while(1) {
-		sleep(enable_stats);
-
-		/* Clear screen and move to top left */
-		printf("%s%s", clr, top_left);
-
-		printf("\nDevice statistics ====================================");
-
-		dev_ll = ll_root_used;
-		while (dev_ll != NULL) {
-			device_fh = (uint32_t)dev_ll->dev->device_fh;
-			tx_total = dev_statistics[device_fh].tx_total;
-			tx = dev_statistics[device_fh].tx;
-			tx_dropped = tx_total - tx;
-			if (zero_copy == 0) {
-				rx_total = rte_atomic64_read(
-					&dev_statistics[device_fh].rx_total_atomic);
-				rx = rte_atomic64_read(
-					&dev_statistics[device_fh].rx_atomic);
-			} else {
-				rx_total = dev_statistics[device_fh].rx_total;
-				rx = dev_statistics[device_fh].rx;
-			}
-			rx_dropped = rx_total - rx;
-
-			printf("\nStatistics for device %"PRIu32" ------------------------------"
-					"\nTX total: 		%"PRIu64""
-					"\nTX dropped: 		%"PRIu64""
-					"\nTX successful: 		%"PRIu64""
-					"\nRX total: 		%"PRIu64""
-					"\nRX dropped: 		%"PRIu64""
-					"\nRX successful: 		%"PRIu64"",
-					device_fh,
-					tx_total,
-					tx_dropped,
-					tx,
-					rx_total,
-					rx_dropped,
-					rx);
-
-			dev_ll = dev_ll->next;
-		}
-		printf("\n======================================================\n");
-	}
-}
-
-static void
-setup_mempool_tbl(int socket, uint32_t index, char *pool_name,
-	char *ring_name, uint32_t nb_mbuf)
-{
-	uint16_t roomsize = VIRTIO_DESCRIPTOR_LEN_ZCP + RTE_PKTMBUF_HEADROOM;
-	vpool_array[index].pool
-		= rte_mempool_create(pool_name, nb_mbuf, MBUF_SIZE_ZCP,
-		MBUF_CACHE_SIZE_ZCP, sizeof(struct rte_pktmbuf_pool_private),
-		rte_pktmbuf_pool_init, (void *)(uintptr_t)roomsize,
-		rte_pktmbuf_init, NULL, socket, 0);
-	if (vpool_array[index].pool != NULL) {
-		vpool_array[index].ring
-			= rte_ring_create(ring_name,
-				rte_align32pow2(nb_mbuf + 1),
-				socket, RING_F_SP_ENQ | RING_F_SC_DEQ);
-		if (likely(vpool_array[index].ring != NULL)) {
-			LOG_DEBUG(VHOST_CONFIG,
-				"in setup_mempool_tbl: mbuf count in "
-				"mempool is: %d\n",
-				rte_mempool_count(vpool_array[index].pool));
-			LOG_DEBUG(VHOST_CONFIG,
-				"in setup_mempool_tbl: mbuf count in "
-				"ring   is: %d\n",
-				rte_ring_count(vpool_array[index].ring));
-		} else {
-			rte_exit(EXIT_FAILURE, "ring_create(%s) failed",
-				ring_name);
-		}
-
-		/* Need consider head room. */
-		vpool_array[index].buf_size = roomsize - RTE_PKTMBUF_HEADROOM;
-	} else {
-		rte_exit(EXIT_FAILURE, "mempool_create(%s) failed", pool_name);
-	}
-}
-
-
-/*
- * Main function, does initialisation and calls the per-lcore functions. The CUSE
- * device is also registered here to handle the IOCTLs.
- */
-int
-MAIN(int argc, char *argv[])
-{
-	struct rte_mempool *mbuf_pool = NULL;
-	unsigned lcore_id, core_id = 0;
-	unsigned nb_ports, valid_num_ports;
-	int ret;
-	uint8_t portid, queue_id = 0;
-	static pthread_t tid;
-
-	/* init EAL */
-	ret = rte_eal_init(argc, argv);
-	if (ret < 0)
-		rte_exit(EXIT_FAILURE, "Error with EAL initialization\n");
-	argc -= ret;
-	argv += ret;
-
-	/* parse app arguments */
-	ret = us_vhost_parse_args(argc, argv);
-	if (ret < 0)
-		rte_exit(EXIT_FAILURE, "Invalid argument\n");
-
-	if (rte_eal_pci_probe() != 0)
-		rte_exit(EXIT_FAILURE, "Error with NIC driver initialization\n");
-
-	for (lcore_id = 0; lcore_id < RTE_MAX_LCORE; lcore_id ++)
-		if (rte_lcore_is_enabled(lcore_id))
-			lcore_ids[core_id ++] = lcore_id;
-
-	if (rte_lcore_count() > RTE_MAX_LCORE)
-		rte_exit(EXIT_FAILURE,"Not enough cores\n");
-
-	/*set the number of swithcing cores available*/
-	num_switching_cores = rte_lcore_count()-1;
-
-	/* Get the number of physical ports. */
-	nb_ports = rte_eth_dev_count();
-	if (nb_ports > RTE_MAX_ETHPORTS)
-		nb_ports = RTE_MAX_ETHPORTS;
-
-	/*
-	 * Update the global var NUM_PORTS and global array PORTS
-	 * and get value of var VALID_NUM_PORTS according to system ports number
-	 */
-	valid_num_ports = check_ports_num(nb_ports);
-
-	if ((valid_num_ports ==  0) || (valid_num_ports > MAX_SUP_PORTS)) {
-		RTE_LOG(INFO, VHOST_PORT, "Current enabled port number is %u,"
-			"but only %u port can be enabled\n",num_ports, MAX_SUP_PORTS);
-		return -1;
-	}
-
-	if (zero_copy == 0) {
-		/* Create the mbuf pool. */
-		mbuf_pool = rte_mempool_create(
-				"MBUF_POOL",
-				NUM_MBUFS_PER_PORT
-				* valid_num_ports,
-				MBUF_SIZE, MBUF_CACHE_SIZE,
-				sizeof(struct rte_pktmbuf_pool_private),
-				rte_pktmbuf_pool_init, NULL,
-				rte_pktmbuf_init, NULL,
-				rte_socket_id(), 0);
-		if (mbuf_pool == NULL)
-			rte_exit(EXIT_FAILURE, "Cannot create mbuf pool\n");
-
-		for (queue_id = 0; queue_id < MAX_QUEUES + 1; queue_id++)
-			vpool_array[queue_id].pool = mbuf_pool;
-
-		if (vm2vm_mode == VM2VM_HARDWARE) {
-			/* Enable VT loop back to let L2 switch to do it. */
-			vmdq_conf_default.rx_adv_conf.vmdq_rx_conf.enable_loop_back = 1;
-			LOG_DEBUG(VHOST_CONFIG,
-				"Enable loop back for L2 switch in vmdq.\n");
-		}
-	} else {
-		uint32_t nb_mbuf;
-		char pool_name[RTE_MEMPOOL_NAMESIZE];
-		char ring_name[RTE_MEMPOOL_NAMESIZE];
-
-		rx_conf_default.start_rx_per_q = (uint8_t)zero_copy;
-		rx_conf_default.rx_drop_en = 0;
-		tx_conf_default.start_tx_per_q = (uint8_t)zero_copy;
-		nb_mbuf = num_rx_descriptor
-			+ num_switching_cores * MBUF_CACHE_SIZE_ZCP
-			+ num_switching_cores * MAX_PKT_BURST;
-
-		for (queue_id = 0; queue_id < MAX_QUEUES; queue_id++) {
-			snprintf(pool_name, sizeof(pool_name),
-				"rxmbuf_pool_%u", queue_id);
-			snprintf(ring_name, sizeof(ring_name),
-				"rxmbuf_ring_%u", queue_id);
-			setup_mempool_tbl(rte_socket_id(), queue_id,
-				pool_name, ring_name, nb_mbuf);
-		}
-
-		nb_mbuf = num_tx_descriptor
-				+ num_switching_cores * MBUF_CACHE_SIZE_ZCP
-				+ num_switching_cores * MAX_PKT_BURST;
-
-		for (queue_id = 0; queue_id < MAX_QUEUES; queue_id++) {
-			snprintf(pool_name, sizeof(pool_name),
-				"txmbuf_pool_%u", queue_id);
-			snprintf(ring_name, sizeof(ring_name),
-				"txmbuf_ring_%u", queue_id);
-			setup_mempool_tbl(rte_socket_id(),
-				(queue_id + MAX_QUEUES),
-				pool_name, ring_name, nb_mbuf);
-		}
-
-		if (vm2vm_mode == VM2VM_HARDWARE) {
-			/* Enable VT loop back to let L2 switch to do it. */
-			vmdq_conf_default.rx_adv_conf.vmdq_rx_conf.enable_loop_back = 1;
-			LOG_DEBUG(VHOST_CONFIG,
-				"Enable loop back for L2 switch in vmdq.\n");
-		}
-	}
-	/* Set log level. */
-	rte_set_log_level(LOG_LEVEL);
-
-	/* initialize all ports */
-	for (portid = 0; portid < nb_ports; portid++) {
-		/* skip ports that are not enabled */
-		if ((enabled_port_mask & (1 << portid)) == 0) {
-			RTE_LOG(INFO, VHOST_PORT,
-				"Skipping disabled port %d\n", portid);
-			continue;
-		}
-		if (port_init(portid) != 0)
-			rte_exit(EXIT_FAILURE,
-				"Cannot initialize network ports\n");
-	}
-
-	/* Initialise all linked lists. */
-	if (init_data_ll() == -1)
-		rte_exit(EXIT_FAILURE, "Failed to initialize linked list\n");
-
-	/* Initialize device stats */
-	memset(&dev_statistics, 0, sizeof(dev_statistics));
-
-	/* Enable stats if the user option is set. */
-	if (enable_stats)
-		pthread_create(&tid, NULL, (void*)print_stats, NULL );
-
-	/* Launch all data cores. */
-	if (zero_copy == 0) {
-		RTE_LCORE_FOREACH_SLAVE(lcore_id) {
-			rte_eal_remote_launch(switch_worker,
-				mbuf_pool, lcore_id);
-		}
-	} else {
-		uint32_t count_in_mempool, index, i;
-		for (index = 0; index < 2*MAX_QUEUES; index++) {
-			/* For all RX and TX queues. */
-			count_in_mempool
-				= rte_mempool_count(vpool_array[index].pool);
-
-			/*
-			 * Transfer all un-attached mbufs from vpool.pool
-			 * to vpoo.ring.
-			 */
-			for (i = 0; i < count_in_mempool; i++) {
-				struct rte_mbuf *mbuf
-					= __rte_mbuf_raw_alloc(
-						vpool_array[index].pool);
-				rte_ring_sp_enqueue(vpool_array[index].ring,
-						(void *)mbuf);
-			}
-
-			LOG_DEBUG(VHOST_CONFIG,
-				"in MAIN: mbuf count in mempool at initial "
-				"is: %d\n", count_in_mempool);
-			LOG_DEBUG(VHOST_CONFIG,
-				"in MAIN: mbuf count in  ring at initial  is :"
-				" %d\n",
-				rte_ring_count(vpool_array[index].ring));
-		}
-
-		RTE_LCORE_FOREACH_SLAVE(lcore_id)
-			rte_eal_remote_launch(switch_worker_zcp, NULL,
-				lcore_id);
-	}
-
-	/* Register CUSE device to handle IOCTLs. */
-	ret = register_cuse_device((char*)&dev_basename, dev_index, get_virtio_net_callbacks());
-	if (ret != 0)
-		rte_exit(EXIT_FAILURE,"CUSE device setup failure.\n");
-
-	init_virtio_net(&virtio_net_device_ops);
-
-	/* Start CUSE session. */
-	start_cuse_session_loop();
-	return 0;
-
-}
-
diff --git a/lib/librte_vhost/main.h b/lib/librte_vhost/main.h
deleted file mode 100644
index c15d938..0000000
--- a/lib/librte_vhost/main.h
+++ /dev/null
@@ -1,86 +0,0 @@
-/*-
- *   BSD LICENSE
- *
- *   Copyright(c) 2010-2014 Intel Corporation. All rights reserved.
- *   All rights reserved.
- *
- *   Redistribution and use in source and binary forms, with or without
- *   modification, are permitted provided that the following conditions
- *   are met:
- *
- *     * Redistributions of source code must retain the above copyright
- *       notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above copyright
- *       notice, this list of conditions and the following disclaimer in
- *       the documentation and/or other materials provided with the
- *       distribution.
- *     * Neither the name of Intel Corporation nor the names of its
- *       contributors may be used to endorse or promote products derived
- *       from this software without specific prior written permission.
- *
- *   THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- *   "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- *   LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- *   A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- *   OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- *   SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- *   LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- *   DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- *   THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- *   (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- *   OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
- */
-
-#ifndef _MAIN_H_
-#define _MAIN_H_
-
-#ifdef RTE_EXEC_ENV_BAREMETAL
-#define MAIN _main
-#else
-#define MAIN main
-#endif
-
-//#define DEBUG
-
-#ifdef DEBUG
-#define LOG_LEVEL RTE_LOG_DEBUG
-#define LOG_DEBUG(log_type, fmt, args...) do {	\
-	RTE_LOG(DEBUG, log_type, fmt, ##args);		\
-} while (0)
-#else
-#define LOG_LEVEL RTE_LOG_INFO
-#define LOG_DEBUG(log_type, fmt, args...) do{} while(0)
-#endif
-
-/* Macros for printing using RTE_LOG */
-#define RTE_LOGTYPE_VHOST_CONFIG RTE_LOGTYPE_USER1
-#define RTE_LOGTYPE_VHOST_DATA   RTE_LOGTYPE_USER2
-#define RTE_LOGTYPE_VHOST_PORT   RTE_LOGTYPE_USER3
-
-/*
- * Device linked list structure for data path.
- */
-struct virtio_net_data_ll
-{
-	struct virtio_net			*dev;	/* Pointer to device created by configuration core. */
-	struct virtio_net_data_ll	*next;  /* Pointer to next device in linked list. */
-};
-
-/*
- * Structure containing data core specific information.
- */
-struct lcore_ll_info
-{
-	struct virtio_net_data_ll	*ll_root_free; 		/* Pointer to head in free linked list. */
-	struct virtio_net_data_ll	*ll_root_used;		/* Pointer to head of used linked list. */
-	uint32_t 					device_num;			/* Number of devices on lcore. */
-	volatile uint8_t			dev_removal_flag;	/* Flag to synchronize device removal. */
-};
-
-struct lcore_info
-{
-	struct lcore_ll_info	*lcore_ll;	/* Pointer to data core specific lcore_ll_info struct */
-};
-
-int MAIN(int argc, char **argv);
-#endif /* _MAIN_H_ */
diff --git a/lib/librte_vhost/rte_virtio_net.h b/lib/librte_vhost/rte_virtio_net.h
new file mode 100644
index 0000000..1a2f0dc
--- /dev/null
+++ b/lib/librte_vhost/rte_virtio_net.h
@@ -0,0 +1,161 @@
+/*-
+ *   BSD LICENSE
+ *
+ *   Copyright(c) 2010-2014 Intel Corporation. All rights reserved.
+ *   All rights reserved.
+ *
+ *   Redistribution and use in source and binary forms, with or without
+ *   modification, are permitted provided that the following conditions
+ *   are met:
+ *
+ *     * Redistributions of source code must retain the above copyright
+ *       notice, this list of conditions and the following disclaimer.
+ *     * Redistributions in binary form must reproduce the above copyright
+ *       notice, this list of conditions and the following disclaimer in
+ *       the documentation and/or other materials provided with the
+ *       distribution.
+ *     * Neither the name of Intel Corporation nor the names of its
+ *       contributors may be used to endorse or promote products derived
+ *       from this software without specific prior written permission.
+ *
+ *   THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ *   "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ *   LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+ *   A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+ *   OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+ *   SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+ *   LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+ *   DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+ *   THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ *   (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+ *   OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#ifndef _VIRTIO_NET_H_
+#define _VIRTIO_NET_H_
+
+/* Used to indicate that the device is running on a data core */
+#define VIRTIO_DEV_RUNNING 1
+
+/* Backend value set by guest. */
+#define VIRTIO_DEV_STOPPED -1
+
+#define PAGE_SIZE   4096
+
+/* Enum for virtqueue management. */
+enum {VIRTIO_RXQ, VIRTIO_TXQ, VIRTIO_QNUM};
+
+#define BUF_VECTOR_MAX 256
+
+/*
+ * Structure contains buffer address, length and descriptor index
+ * from vring to do scatter RX.
+*/
+struct buf_vector {
+uint64_t buf_addr;
+uint32_t buf_len;
+uint32_t desc_idx;
+};
+
+/*
+ * Structure contains variables relevant to TX/RX virtqueues.
+ */
+struct vhost_virtqueue
+{
+	struct vring_desc	*desc;				/* Virtqueue descriptor ring. */
+	struct vring_avail	*avail;				/* Virtqueue available ring. */
+	struct vring_used	*used;				/* Virtqueue used ring. */
+	uint32_t			size;				/* Size of descriptor ring. */
+	uint32_t			backend;			/* Backend value to determine if device should started/stopped. */
+	uint16_t			vhost_hlen;			/* Vhost header length (varies depending on RX merge buffers. */
+	volatile uint16_t	last_used_idx;		/* Last index used on the available ring */
+	volatile uint16_t	last_used_idx_res;	/* Used for multiple devices reserving buffers. */
+	eventfd_t			callfd;				/* Currently unused as polling mode is enabled. */
+	eventfd_t			kickfd;				/* Used to notify the guest (trigger interrupt). */
+	/* Used for scatter RX. */
+	struct buf_vector	buf_vec[BUF_VECTOR_MAX];
+} __rte_cache_aligned;
+
+/*
+ * Device structure contains all configuration information relating to the device.
+ */
+struct virtio_net
+{
+	struct vhost_virtqueue	*virtqueue[VIRTIO_QNUM];	/* Contains all virtqueue information. */
+	struct virtio_memory 	*mem;						/* QEMU memory and memory region information. */
+	struct ether_addr 		mac_address;				/* Device MAC address (Obtained on first TX packet). */
+	uint64_t 				features;					/* Negotiated feature set. */
+	uint64_t 				device_fh;					/* device identifier. */
+	uint32_t 				vmdq_rx_q;					/* RX VMDQ queue number. */
+	uint32_t 				flags;						/* Device flags. Only used to check if device is running on data core. */
+	uint32_t 				vlan_tag;					/* Vlan tag for device. Currently set to device_id (0-63). */
+	uint16_t 				coreid;						/* Data core that the device is added to. */
+	volatile uint8_t 		ready;						/* A device is set as ready if the MAC address has been set. */
+	volatile uint8_t		remove;						/* Device is marked for removal from the data core. */
+} __rte_cache_aligned;
+
+/*
+ * Device linked list structure for configuration.
+ */
+struct virtio_net_config_ll
+{
+	struct virtio_net		dev;	/* Virtio device. */
+	struct virtio_net_config_ll	*next; /* Next entry on linked list. */
+};
+
+/*
+ * Information relating to memory regions including offsets to addresses in QEMUs memory file.
+ */
+struct virtio_memory_regions {
+	uint64_t	guest_phys_address;		/* Base guest physical address of region. */
+	uint64_t	guest_phys_address_end;	/* End guest physical address of region. */
+	uint64_t	memory_size;			/* Size of region. */
+	uint64_t	userspace_address;		/* Base userspace address of region. */
+	uint64_t	address_offset;			/* Offset of region for address translation. */
+};
+
+/*
+ * Information relating to memory regions including offsets to
+ * addresses in host physical space.
+ */
+struct virtio_memory_regions_hpa {
+	/* Base guest physical address of region. */
+	uint64_t	guest_phys_address;
+	/* End guest physical address of region. */
+	uint64_t	guest_phys_address_end;
+	/* Size of region. */
+	uint64_t	memory_size;
+	/* Offset of region for gpa to hpa translation. */
+	uint64_t	host_phys_addr_offset;
+};
+
+/*
+ * Memory structure includes region and mapping information.
+ */
+struct virtio_memory {
+	uint64_t			base_address;			/* Base QEMU userspace address of the memory file. */
+	uint64_t			mapped_address;			/* Mapped address of memory file base in our applications memory space. */
+	uint64_t			mapped_size;			/* Total size of memory file. */
+	uint32_t			nregions;				/* Number of memory regions. */
+	 /* Number of memory regions for gpa to hpa translation. */
+	uint32_t			nregions_hpa;
+	/* Memory region information for gpa to hpa translation. */
+	struct virtio_memory_regions_hpa  *regions_hpa;
+	/* Memory region information. */
+	struct virtio_memory_regions      regions[0];
+};
+
+/*
+ * Device operations to add/remove device.
+ */
+struct virtio_net_device_ops {
+	int (* new_device) 		(struct virtio_net *);	/* Add device. */
+	void (* destroy_device)	(volatile struct virtio_net *);	/* Remove device. */
+};
+
+int init_virtio_net(struct virtio_net_device_ops const * const);
+int deinit_virtio_net(void);
+
+struct vhost_net_device_ops const * get_virtio_net_callbacks(void);
+
+#endif /* _VIRTIO_NET_H_ */
diff --git a/lib/librte_vhost/vhost_rxtx.c b/lib/librte_vhost/vhost_rxtx.c
new file mode 100644
index 0000000..78fce0d
--- /dev/null
+++ b/lib/librte_vhost/vhost_rxtx.c
@@ -0,0 +1,281 @@
+/*-
+ *   BSD LICENSE
+ *
+ *   Copyright(c) 2010-2014 Intel Corporation. All rights reserved.
+ *   All rights reserved.
+ *
+ *   Redistribution and use in source and binary forms, with or without
+ *   modification, are permitted provided that the following conditions
+ *   are met:
+ *
+ *     * Redistributions of source code must retain the above copyright
+ *       notice, this list of conditions and the following disclaimer.
+ *     * Redistributions in binary form must reproduce the above copyright
+ *       notice, this list of conditions and the following disclaimer in
+ *       the documentation and/or other materials provided with the
+ *       distribution.
+ *     * Neither the name of Intel Corporation nor the names of its
+ *       contributors may be used to endorse or promote products derived
+ *       from this software without specific prior written permission.
+ *
+ *   THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ *   "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ *   LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+ *   A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+ *   OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+ *   SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+ *   LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+ *   DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+ *   THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ *   (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+ *   OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#include <stdint.h>
+#include <linux/virtio_net.h>
+
+#include <rte_mbuf.h>
+#include <rte_memcpy.h>
+#include <rte_virtio_net.h>
+
+#include "vhost-net-cdev.h"
+
+#define MAX_PKT_BURST 64
+#define MAX_MRG_PKT_BURST 64
+
+/*
+ * This function adds buffers to the virtio devices RX virtqueue. Buffers can
+ * be received from the physical port or from another virtio device. A packet
+ * count is returned to indicate the number of packets that were succesfully
+ * added to the RX queue. This function works when mergeable is disabled.
+ */
+static inline uint32_t __attribute__((always_inline))
+virtio_dev_rx(struct virtio_net *dev, struct rte_mbuf **pkts, uint32_t count)
+{
+	struct vhost_virtqueue *vq;
+	struct vring_desc *desc;
+	struct rte_mbuf *buff;
+	/* The virtio_hdr is initialised to 0. */
+	struct virtio_net_hdr_mrg_rxbuf virtio_hdr = {{0,0,0,0,0,0},0};
+	uint64_t buff_addr = 0;
+	uint64_t buff_hdr_addr = 0;
+	uint32_t head[MAX_PKT_BURST], packet_len = 0;
+	uint32_t head_idx, packet_success = 0;
+	uint32_t retry = 0;
+	uint16_t avail_idx, res_cur_idx;
+	uint16_t res_base_idx, res_end_idx;
+	uint16_t free_entries;
+	uint8_t success = 0;
+
+	LOG_DEBUG(VHOST_DATA, "(%"PRIu64") virtio_dev_rx()\n", dev->device_fh);
+	vq = dev->virtqueue[VIRTIO_RXQ];
+	count = (count > MAX_PKT_BURST) ? MAX_PKT_BURST : count;
+
+	/* As many data cores may want access to available buffers, they need to be reserved. */
+	do {
+		res_base_idx = vq->last_used_idx_res;
+		avail_idx = *((volatile uint16_t *)&vq->avail->idx);
+
+		free_entries = (avail_idx - res_base_idx);
+		/* If retry is enabled and the queue is full then we wait and retry to avoid packet loss. */
+		if (enable_retry && unlikely(count > free_entries)) {
+			for (retry = 0; retry < burst_rx_retry_num; retry++) {
+				rte_delay_us(burst_rx_delay_time);
+				avail_idx =
+					*((volatile uint16_t *)&vq->avail->idx);
+				free_entries = (avail_idx - res_base_idx);
+				if (count <= free_entries)
+					break;
+			}
+		}
+
+		/*check that we have enough buffers*/
+		if (unlikely(count > free_entries))
+			count = free_entries;
+
+		if (count == 0)
+			return 0;
+
+		res_end_idx = res_base_idx + count;
+		/* vq->last_used_idx_res is atomically updated. */
+		success = rte_atomic16_cmpset(&vq->last_used_idx_res, res_base_idx,
+									res_end_idx);
+	} while (unlikely(success == 0));
+	res_cur_idx = res_base_idx;
+	LOG_DEBUG(VHOST_DATA, "(%"PRIu64") Current Index %d| End Index %d\n", dev->device_fh, res_cur_idx, res_end_idx);
+
+	/* Prefetch available ring to retrieve indexes. */
+	rte_prefetch0(&vq->avail->ring[res_cur_idx & (vq->size - 1)]);
+
+	/* Retrieve all of the head indexes first to avoid caching issues. */
+	for (head_idx = 0; head_idx < count; head_idx++)
+		head[head_idx] = vq->avail->ring[(res_cur_idx + head_idx) & (vq->size - 1)];
+
+	/*Prefetch descriptor index. */
+	rte_prefetch0(&vq->desc[head[packet_success]]);
+
+	while (res_cur_idx != res_end_idx) {
+		/* Get descriptor from available ring */
+		desc = &vq->desc[head[packet_success]];
+
+		buff = pkts[packet_success];
+
+		/* Convert from gpa to vva (guest physical addr -> vhost virtual addr) */
+		buff_addr = gpa_to_vva(dev, desc->addr);
+		/* Prefetch buffer address. */
+		rte_prefetch0((void*)(uintptr_t)buff_addr);
+
+		/* Copy virtio_hdr to packet and increment buffer address */
+		buff_hdr_addr = buff_addr;
+		packet_len = rte_pktmbuf_data_len(buff) + vq->vhost_hlen;
+
+		/*
+		 * If the descriptors are chained the header and data are
+		 * placed in separate buffers.
+		 */
+		if (desc->flags & VRING_DESC_F_NEXT) {
+			desc->len = vq->vhost_hlen;
+			desc = &vq->desc[desc->next];
+			/* Buffer address translation. */
+			buff_addr = gpa_to_vva(dev, desc->addr);
+			desc->len = rte_pktmbuf_data_len(buff);
+		} else {
+			buff_addr += vq->vhost_hlen;
+			desc->len = packet_len;
+		}
+
+		/* Update used ring with desc information */
+		vq->used->ring[res_cur_idx & (vq->size - 1)].id = head[packet_success];
+		vq->used->ring[res_cur_idx & (vq->size - 1)].len = packet_len;
+
+		/* Copy mbuf data to buffer */
+		rte_memcpy((void *)(uintptr_t)buff_addr,
+			(const void *)buff->pkt.data,
+			rte_pktmbuf_data_len(buff));
+		PRINT_PACKET(dev, (uintptr_t)buff_addr,
+			rte_pktmbuf_data_len(buff), 0);
+
+		res_cur_idx++;
+		packet_success++;
+
+		rte_memcpy((void *)(uintptr_t)buff_hdr_addr,
+			(const void *)&virtio_hdr, vq->vhost_hlen);
+
+		PRINT_PACKET(dev, (uintptr_t)buff_hdr_addr, vq->vhost_hlen, 1);
+
+		if (res_cur_idx < res_end_idx) {
+			/* Prefetch descriptor index. */
+			rte_prefetch0(&vq->desc[head[packet_success]]);
+		}
+	}
+
+	rte_compiler_barrier();
+
+	/* Wait until it's our turn to add our buffer to the used ring. */
+	while (unlikely(vq->last_used_idx != res_base_idx))
+		rte_pause();
+
+	*(volatile uint16_t *)&vq->used->idx += count;
+	vq->last_used_idx = res_end_idx;
+
+	/* Kick the guest if necessary. */
+	if (!(vq->avail->flags & VRING_AVAIL_F_NO_INTERRUPT))
+		eventfd_write((int)vq->kickfd, 1);
+	return count;
+}
+
+
+static inline void __attribute__((always_inline))
+virtio_dev_tx(struct virtio_net* dev, struct rte_mempool *mbuf_pool)
+{
+	struct rte_mbuf m;
+	struct vhost_virtqueue *vq;
+	struct vring_desc *desc;
+	uint64_t buff_addr = 0;
+	uint32_t head[MAX_PKT_BURST];
+	uint32_t used_idx;
+	uint32_t i;
+	uint16_t free_entries, packet_success = 0;
+	uint16_t avail_idx;
+
+	vq = dev->virtqueue[VIRTIO_TXQ];
+	avail_idx =  *((volatile uint16_t *)&vq->avail->idx);
+
+	/* If there are no available buffers then return. */
+	if (vq->last_used_idx == avail_idx)
+		return;
+
+	LOG_DEBUG(VHOST_DATA, "(%"PRIu64") virtio_dev_tx()\n", dev->device_fh);
+
+	/* Prefetch available ring to retrieve head indexes. */
+	rte_prefetch0(&vq->avail->ring[vq->last_used_idx & (vq->size - 1)]);
+
+	/*get the number of free entries in the ring*/
+	free_entries = (avail_idx - vq->last_used_idx);
+
+	/* Limit to MAX_PKT_BURST. */
+	if (free_entries > MAX_PKT_BURST)
+		free_entries = MAX_PKT_BURST;
+
+	LOG_DEBUG(VHOST_DATA, "(%"PRIu64") Buffers available %d\n", dev->device_fh, free_entries);
+	/* Retrieve all of the head indexes first to avoid caching issues. */
+	for (i = 0; i < free_entries; i++)
+		head[i] = vq->avail->ring[(vq->last_used_idx + i) & (vq->size - 1)];
+
+	/* Prefetch descriptor index. */
+	rte_prefetch0(&vq->desc[head[packet_success]]);
+	rte_prefetch0(&vq->used->ring[vq->last_used_idx & (vq->size - 1)]);
+
+	while (packet_success < free_entries) {
+		desc = &vq->desc[head[packet_success]];
+
+		/* Discard first buffer as it is the virtio header */
+		desc = &vq->desc[desc->next];
+
+		/* Buffer address translation. */
+		buff_addr = gpa_to_vva(dev, desc->addr);
+		/* Prefetch buffer address. */
+		rte_prefetch0((void*)(uintptr_t)buff_addr);
+
+		used_idx = vq->last_used_idx & (vq->size - 1);
+
+		if (packet_success < (free_entries - 1)) {
+			/* Prefetch descriptor index. */
+			rte_prefetch0(&vq->desc[head[packet_success+1]]);
+			rte_prefetch0(&vq->used->ring[(used_idx + 1) & (vq->size - 1)]);
+		}
+
+		/* Update used index buffer information. */
+		vq->used->ring[used_idx].id = head[packet_success];
+		vq->used->ring[used_idx].len = 0;
+
+		/* Setup dummy mbuf. This is copied to a real mbuf if transmitted out the physical port. */
+		m.pkt.data_len = desc->len;
+		m.pkt.pkt_len = desc->len;
+		m.pkt.data = (void*)(uintptr_t)buff_addr;
+
+		PRINT_PACKET(dev, (uintptr_t)buff_addr, desc->len, 0);
+
+		/* If this is the first received packet we need to learn the MAC and setup VMDQ */
+		if (dev->ready == DEVICE_MAC_LEARNING) {
+			if (dev->remove || (link_vmdq(dev, &m) == -1)) {
+				/*discard frame if device is scheduled for removal or a duplicate MAC address is found. */
+				packet_success += free_entries;
+				vq->last_used_idx += packet_success;
+				break;
+			}
+		}
+		virtio_tx_route(dev, &m, mbuf_pool, (uint16_t)dev->device_fh);
+
+		vq->last_used_idx++;
+		packet_success++;
+	}
+
+	rte_compiler_barrier();
+	vq->used->idx += packet_success;
+	/* Kick guest if required. */
+	if (!(vq->avail->flags & VRING_AVAIL_F_NO_INTERRUPT))
+		eventfd_write((int)vq->kickfd, 1);
+}
+
+
diff --git a/lib/librte_vhost/virtio-net.h b/lib/librte_vhost/virtio-net.h
deleted file mode 100644
index 1a2f0dc..0000000
--- a/lib/librte_vhost/virtio-net.h
+++ /dev/null
@@ -1,161 +0,0 @@
-/*-
- *   BSD LICENSE
- *
- *   Copyright(c) 2010-2014 Intel Corporation. All rights reserved.
- *   All rights reserved.
- *
- *   Redistribution and use in source and binary forms, with or without
- *   modification, are permitted provided that the following conditions
- *   are met:
- *
- *     * Redistributions of source code must retain the above copyright
- *       notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above copyright
- *       notice, this list of conditions and the following disclaimer in
- *       the documentation and/or other materials provided with the
- *       distribution.
- *     * Neither the name of Intel Corporation nor the names of its
- *       contributors may be used to endorse or promote products derived
- *       from this software without specific prior written permission.
- *
- *   THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- *   "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- *   LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- *   A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- *   OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- *   SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- *   LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- *   DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- *   THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- *   (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- *   OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
- */
-
-#ifndef _VIRTIO_NET_H_
-#define _VIRTIO_NET_H_
-
-/* Used to indicate that the device is running on a data core */
-#define VIRTIO_DEV_RUNNING 1
-
-/* Backend value set by guest. */
-#define VIRTIO_DEV_STOPPED -1
-
-#define PAGE_SIZE   4096
-
-/* Enum for virtqueue management. */
-enum {VIRTIO_RXQ, VIRTIO_TXQ, VIRTIO_QNUM};
-
-#define BUF_VECTOR_MAX 256
-
-/*
- * Structure contains buffer address, length and descriptor index
- * from vring to do scatter RX.
-*/
-struct buf_vector {
-uint64_t buf_addr;
-uint32_t buf_len;
-uint32_t desc_idx;
-};
-
-/*
- * Structure contains variables relevant to TX/RX virtqueues.
- */
-struct vhost_virtqueue
-{
-	struct vring_desc	*desc;				/* Virtqueue descriptor ring. */
-	struct vring_avail	*avail;				/* Virtqueue available ring. */
-	struct vring_used	*used;				/* Virtqueue used ring. */
-	uint32_t			size;				/* Size of descriptor ring. */
-	uint32_t			backend;			/* Backend value to determine if device should started/stopped. */
-	uint16_t			vhost_hlen;			/* Vhost header length (varies depending on RX merge buffers. */
-	volatile uint16_t	last_used_idx;		/* Last index used on the available ring */
-	volatile uint16_t	last_used_idx_res;	/* Used for multiple devices reserving buffers. */
-	eventfd_t			callfd;				/* Currently unused as polling mode is enabled. */
-	eventfd_t			kickfd;				/* Used to notify the guest (trigger interrupt). */
-	/* Used for scatter RX. */
-	struct buf_vector	buf_vec[BUF_VECTOR_MAX];
-} __rte_cache_aligned;
-
-/*
- * Device structure contains all configuration information relating to the device.
- */
-struct virtio_net
-{
-	struct vhost_virtqueue	*virtqueue[VIRTIO_QNUM];	/* Contains all virtqueue information. */
-	struct virtio_memory 	*mem;						/* QEMU memory and memory region information. */
-	struct ether_addr 		mac_address;				/* Device MAC address (Obtained on first TX packet). */
-	uint64_t 				features;					/* Negotiated feature set. */
-	uint64_t 				device_fh;					/* device identifier. */
-	uint32_t 				vmdq_rx_q;					/* RX VMDQ queue number. */
-	uint32_t 				flags;						/* Device flags. Only used to check if device is running on data core. */
-	uint32_t 				vlan_tag;					/* Vlan tag for device. Currently set to device_id (0-63). */
-	uint16_t 				coreid;						/* Data core that the device is added to. */
-	volatile uint8_t 		ready;						/* A device is set as ready if the MAC address has been set. */
-	volatile uint8_t		remove;						/* Device is marked for removal from the data core. */
-} __rte_cache_aligned;
-
-/*
- * Device linked list structure for configuration.
- */
-struct virtio_net_config_ll
-{
-	struct virtio_net		dev;	/* Virtio device. */
-	struct virtio_net_config_ll	*next; /* Next entry on linked list. */
-};
-
-/*
- * Information relating to memory regions including offsets to addresses in QEMUs memory file.
- */
-struct virtio_memory_regions {
-	uint64_t	guest_phys_address;		/* Base guest physical address of region. */
-	uint64_t	guest_phys_address_end;	/* End guest physical address of region. */
-	uint64_t	memory_size;			/* Size of region. */
-	uint64_t	userspace_address;		/* Base userspace address of region. */
-	uint64_t	address_offset;			/* Offset of region for address translation. */
-};
-
-/*
- * Information relating to memory regions including offsets to
- * addresses in host physical space.
- */
-struct virtio_memory_regions_hpa {
-	/* Base guest physical address of region. */
-	uint64_t	guest_phys_address;
-	/* End guest physical address of region. */
-	uint64_t	guest_phys_address_end;
-	/* Size of region. */
-	uint64_t	memory_size;
-	/* Offset of region for gpa to hpa translation. */
-	uint64_t	host_phys_addr_offset;
-};
-
-/*
- * Memory structure includes region and mapping information.
- */
-struct virtio_memory {
-	uint64_t			base_address;			/* Base QEMU userspace address of the memory file. */
-	uint64_t			mapped_address;			/* Mapped address of memory file base in our applications memory space. */
-	uint64_t			mapped_size;			/* Total size of memory file. */
-	uint32_t			nregions;				/* Number of memory regions. */
-	 /* Number of memory regions for gpa to hpa translation. */
-	uint32_t			nregions_hpa;
-	/* Memory region information for gpa to hpa translation. */
-	struct virtio_memory_regions_hpa  *regions_hpa;
-	/* Memory region information. */
-	struct virtio_memory_regions      regions[0];
-};
-
-/*
- * Device operations to add/remove device.
- */
-struct virtio_net_device_ops {
-	int (* new_device) 		(struct virtio_net *);	/* Add device. */
-	void (* destroy_device)	(volatile struct virtio_net *);	/* Remove device. */
-};
-
-int init_virtio_net(struct virtio_net_device_ops const * const);
-int deinit_virtio_net(void);
-
-struct vhost_net_device_ops const * get_virtio_net_callbacks(void);
-
-#endif /* _VIRTIO_NET_H_ */
-- 
1.8.1.4

^ permalink raw reply	[flat|nested] 23+ messages in thread

* [dpdk-dev] [PATCH v5 03/11] lib/librte_vhost: vhost lib transform
  2014-09-26  9:45 [dpdk-dev] [PATCH v5 00/11] user space vhost library and vhost example Huawei Xie
  2014-09-26  9:45 ` [dpdk-dev] [PATCH v5 01/11] lib/librte_vhost: move src files in vhost example to vhost lib directory Huawei Xie
  2014-09-26  9:45 ` [dpdk-dev] [PATCH v5 02/11] lib/librte_vhost: refactor vhost lib for subsequent transform Huawei Xie
@ 2014-09-26  9:45 ` Huawei Xie
  2014-09-29 19:51   ` Thomas Monjalon
  2014-09-26  9:45 ` [dpdk-dev] [PATCH v5 04/11] lib/librte_vhost: merge vhost merge-able rx. merge vhost tx fix Huawei Xie
                   ` (7 subsequent siblings)
  10 siblings, 1 reply; 23+ messages in thread
From: Huawei Xie @ 2014-09-26  9:45 UTC (permalink / raw)
  To: dev

This vhost lib consists of five APIs plus several other helper routines
for feature disable/enable.
1) rte_vhost_driver_register initialises vhost driver.
2) rte_vhost_driver_callback_register registers the callbacks.
Callbacks are called from vhost driver when virtio device is ready
for polling or is de-activated by guest.
3) rte_vhost_driver_session_start, a blocking API to start vhost
message handler session.
4) rte_vhost_enqueue_burst and rte_vhost_dequeue_burst for
enqueue/dequeue to/from virtio ring.
											
Modifications include:
1) in vhost_rxtx.c
   virtio_dev_rx -> rte_vhost_enqueue_burst
   virtio_dev_tx -> rte_vhost_dequeue_burst
2) VMDQ, MAC learning and other switch related logics are removed.
3) zero copy feature isn't generic at this stage, and is removed.
4) retry logic is removed from vhost rx functions.
The above three logics will be implemented in example as reference.
5) Add several TODO/FIXME:
   -allow application to disable cmpset reserve in rte_vhost_enqueue_burst
in case there is no contention.
   -fix memcpy from mbuf to vring desc when mbuf is chained and the
desc couldn't hold all the data
   -fix vhost_set_mem_table possible race condition: two vqs concurrently
calls set_mem_table which cause saved mem_temp to be overide.
6) merge-able feature is removed, which will be merged in subsequent patch.


Signed-off-by: Huawei Xie <huawei.xie@intel.com>
---
 lib/librte_vhost/Makefile         |  48 ++++++++
 lib/librte_vhost/rte_virtio_net.h | 179 ++++++++++++++++-----------
 lib/librte_vhost/vhost-net-cdev.c |  35 +++---
 lib/librte_vhost/vhost-net-cdev.h |  45 +++++--
 lib/librte_vhost/vhost_rxtx.c     | 157 +++++++++++++-----------
 lib/librte_vhost/virtio-net.c     | 249 +++++++-------------------------------
 6 files changed, 341 insertions(+), 372 deletions(-)
 create mode 100644 lib/librte_vhost/Makefile

diff --git a/lib/librte_vhost/Makefile b/lib/librte_vhost/Makefile
new file mode 100644
index 0000000..6ad706d
--- /dev/null
+++ b/lib/librte_vhost/Makefile
@@ -0,0 +1,48 @@
+#   BSD LICENSE
+#
+#   Copyright(c) 2010-2014 Intel Corporation. All rights reserved.
+#   All rights reserved.
+#
+#   Redistribution and use in source and binary forms, with or without
+#   modification, are permitted provided that the following conditions
+#   are met:
+#
+#     * Redistributions of source code must retain the above copyright
+#       notice, this list of conditions and the following disclaimer.
+#     * Redistributions in binary form must reproduce the above copyright
+#       notice, this list of conditions and the following disclaimer in
+#       the documentation and/or other materials provided with the
+#       distribution.
+#     * Neither the name of Intel Corporation nor the names of its
+#       contributors may be used to endorse or promote products derived
+#       from this software without specific prior written permission.
+#
+#   THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+#   "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+#   LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+#   A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+#   OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+#   SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+#   LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+#   DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+#   THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+#   (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+#   OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+
+include $(RTE_SDK)/mk/rte.vars.mk
+
+# library name
+LIB = librte_vhost.a
+
+CFLAGS += $(WERROR_FLAGS) -I$(SRCDIR) -O3 -D_FILE_OFFSET_BITS=64 -lfuse
+LDFLAGS += -lfuse
+# all source are stored in SRCS-y
+SRCS-$(CONFIG_RTE_LIBRTE_VHOST) := vhost-net-cdev.c virtio-net.c vhost_rxtx.c
+
+# install includes
+SYMLINK-$(CONFIG_RTE_LIBRTE_VHOST)-include += rte_virtio_net.h
+
+# this lib needs eal
+DEPDIRS-$(CONFIG_RTE_LIBRTE_VHOST) += lib/librte_eal lib/librte_mbuf
+
+include $(RTE_SDK)/mk/rte.lib.mk
diff --git a/lib/librte_vhost/rte_virtio_net.h b/lib/librte_vhost/rte_virtio_net.h
index 1a2f0dc..08dc6f4 100644
--- a/lib/librte_vhost/rte_virtio_net.h
+++ b/lib/librte_vhost/rte_virtio_net.h
@@ -34,28 +34,25 @@
 #ifndef _VIRTIO_NET_H_
 #define _VIRTIO_NET_H_
 
+#include <stdint.h>
+#include <linux/virtio_ring.h>
+#include <linux/virtio_net.h>
+#include <sys/eventfd.h>
+
+#include <rte_memory.h>
+#include <rte_mempool.h>
+#include <rte_mbuf.h>
+
 /* Used to indicate that the device is running on a data core */
 #define VIRTIO_DEV_RUNNING 1
 
 /* Backend value set by guest. */
 #define VIRTIO_DEV_STOPPED -1
 
-#define PAGE_SIZE   4096
 
 /* Enum for virtqueue management. */
 enum {VIRTIO_RXQ, VIRTIO_TXQ, VIRTIO_QNUM};
 
-#define BUF_VECTOR_MAX 256
-
-/*
- * Structure contains buffer address, length and descriptor index
- * from vring to do scatter RX.
-*/
-struct buf_vector {
-uint64_t buf_addr;
-uint32_t buf_len;
-uint32_t desc_idx;
-};
 
 /*
  * Structure contains variables relevant to TX/RX virtqueues.
@@ -72,36 +69,8 @@ struct vhost_virtqueue
 	volatile uint16_t	last_used_idx_res;	/* Used for multiple devices reserving buffers. */
 	eventfd_t			callfd;				/* Currently unused as polling mode is enabled. */
 	eventfd_t			kickfd;				/* Used to notify the guest (trigger interrupt). */
-	/* Used for scatter RX. */
-	struct buf_vector	buf_vec[BUF_VECTOR_MAX];
-} __rte_cache_aligned;
-
-/*
- * Device structure contains all configuration information relating to the device.
- */
-struct virtio_net
-{
-	struct vhost_virtqueue	*virtqueue[VIRTIO_QNUM];	/* Contains all virtqueue information. */
-	struct virtio_memory 	*mem;						/* QEMU memory and memory region information. */
-	struct ether_addr 		mac_address;				/* Device MAC address (Obtained on first TX packet). */
-	uint64_t 				features;					/* Negotiated feature set. */
-	uint64_t 				device_fh;					/* device identifier. */
-	uint32_t 				vmdq_rx_q;					/* RX VMDQ queue number. */
-	uint32_t 				flags;						/* Device flags. Only used to check if device is running on data core. */
-	uint32_t 				vlan_tag;					/* Vlan tag for device. Currently set to device_id (0-63). */
-	uint16_t 				coreid;						/* Data core that the device is added to. */
-	volatile uint8_t 		ready;						/* A device is set as ready if the MAC address has been set. */
-	volatile uint8_t		remove;						/* Device is marked for removal from the data core. */
 } __rte_cache_aligned;
 
-/*
- * Device linked list structure for configuration.
- */
-struct virtio_net_config_ll
-{
-	struct virtio_net		dev;	/* Virtio device. */
-	struct virtio_net_config_ll	*next; /* Next entry on linked list. */
-};
 
 /*
  * Information relating to memory regions including offsets to addresses in QEMUs memory file.
@@ -114,48 +83,116 @@ struct virtio_memory_regions {
 	uint64_t	address_offset;			/* Offset of region for address translation. */
 };
 
-/*
- * Information relating to memory regions including offsets to
- * addresses in host physical space.
- */
-struct virtio_memory_regions_hpa {
-	/* Base guest physical address of region. */
-	uint64_t	guest_phys_address;
-	/* End guest physical address of region. */
-	uint64_t	guest_phys_address_end;
-	/* Size of region. */
-	uint64_t	memory_size;
-	/* Offset of region for gpa to hpa translation. */
-	uint64_t	host_phys_addr_offset;
-};
 
-/*
+/**
  * Memory structure includes region and mapping information.
  */
 struct virtio_memory {
-	uint64_t			base_address;			/* Base QEMU userspace address of the memory file. */
-	uint64_t			mapped_address;			/* Mapped address of memory file base in our applications memory space. */
-	uint64_t			mapped_size;			/* Total size of memory file. */
-	uint32_t			nregions;				/* Number of memory regions. */
-	 /* Number of memory regions for gpa to hpa translation. */
-	uint32_t			nregions_hpa;
-	/* Memory region information for gpa to hpa translation. */
-	struct virtio_memory_regions_hpa  *regions_hpa;
-	/* Memory region information. */
-	struct virtio_memory_regions      regions[0];
+	uint64_t    base_address;    /**< Base QEMU userspace address of the memory file. */
+	uint64_t    mapped_address;  /**< Mapped address of memory file base in our applications memory space. */
+	uint64_t    mapped_size;     /**< Total size of memory file. */
+	uint32_t    nregions;        /**< Number of memory regions. */
+	struct virtio_memory_regions      regions[0]; /**< Memory region information. */
 };
 
-/*
+/**
+ * Device structure contains all configuration information relating to the device.
+ */
+struct virtio_net {
+	struct vhost_virtqueue  *virtqueue[VIRTIO_QNUM]; /**< Contains all virtqueue information. */
+	struct virtio_memory    *mem;                    /**< QEMU memory and memory region information. */
+	uint64_t features;    /**< Negotiated feature set. */
+	uint64_t device_fh;   /**< Device identifier. */
+	uint32_t flags;       /**< Device flags. Only used to check if device is running on data core. */
+	void     *priv;
+} __rte_cache_aligned;
+
+/**
  * Device operations to add/remove device.
  */
 struct virtio_net_device_ops {
-	int (* new_device) 		(struct virtio_net *);	/* Add device. */
-	void (* destroy_device)	(volatile struct virtio_net *);	/* Remove device. */
+	int (*new_device)(struct virtio_net *); /**< Add device. */
+	void (*destroy_device)(struct virtio_net *); /**< Remove device. */
 };
 
-int init_virtio_net(struct virtio_net_device_ops const * const);
-int deinit_virtio_net(void);
 
-struct vhost_net_device_ops const * get_virtio_net_callbacks(void);
+static inline uint16_t __attribute__((always_inline))
+rte_vring_available_entries(struct virtio_net *dev, uint16_t queue_id)
+{
+	struct vhost_virtqueue *vq = dev->virtqueue[queue_id];
+	return *(volatile uint16_t *)&vq->avail->idx - vq->last_used_idx_res;
+}
+
+/**
+ * Function to convert guest physical addresses to vhost virtual addresses.
+ * This is used to convert guest virtio buffer addresses.
+ */
+static inline uint64_t __attribute__((always_inline))
+gpa_to_vva(struct virtio_net *dev, uint64_t guest_pa)
+{
+	struct virtio_memory_regions *region;
+	uint32_t regionidx;
+	uint64_t vhost_va = 0;
+
+	for (regionidx = 0; regionidx < dev->mem->nregions; regionidx++) {
+		region = &dev->mem->regions[regionidx];
+		if ((guest_pa >= region->guest_phys_address) &&
+			(guest_pa <= region->guest_phys_address_end)) {
+			vhost_va = region->address_offset + guest_pa;
+			break;
+		}
+	}
+	return vhost_va;
+}
+
+/**
+ *  Disable features in feature_mask. Returns 0 on success.
+ */
+int rte_vhost_feature_disable(uint64_t feature_mask);
+
+/**
+ *  Enable features in feature_mask. Returns 0 on success.
+ */
+int rte_vhost_feature_enable(uint64_t feature_mask);
+
+/* Returns currently supported vhost features */
+uint64_t rte_vhost_feature_get(void);
+
+int rte_vhost_enable_guest_notification(struct virtio_net *dev, uint16_t queue_id, int enable);
+
+/* Register vhost driver. dev_name could be different for multiple instance support. */
+int rte_vhost_driver_register(const char *dev_name);
+
+/* Register callbacks. */
+int rte_vhost_driver_callback_register(struct virtio_net_device_ops const * const);
+
+int rte_vhost_driver_session_start(void);
+
+/**
+ * This function adds buffers to the virtio devices RX virtqueue. Buffers can
+ * be received from the physical port or from another virtual device. A packet
+ * count is returned to indicate the number of packets that were succesfully
+ * added to the RX queue.
+ * @param queue_id
+ *  virtio queue index in mq case
+ * @return
+ *  num of packets enqueued
+ */
+uint32_t rte_vhost_enqueue_burst(struct virtio_net *dev, uint16_t queue_id,
+	struct rte_mbuf **pkts, uint32_t count);
+
+/**
+ * This function gets guest buffers from the virtio device TX virtqueue,
+ * construct host mbufs, copies guest buffer content to host mbufs and
+ * store them in pkts to be processed.
+ * @param mbuf_pool
+ *  mbuf_pool where host mbuf is allocated.
+ * @param queue_id
+ *  virtio queue index in mq case.
+ * @return
+ *  num of packets dequeued
+ */
+uint32_t rte_vhost_dequeue_burst(struct virtio_net *dev, uint16_t queue_id,
+	struct rte_mempool *mbuf_pool, struct rte_mbuf **pkts, uint32_t count);
 
 #endif /* _VIRTIO_NET_H_ */
diff --git a/lib/librte_vhost/vhost-net-cdev.c b/lib/librte_vhost/vhost-net-cdev.c
index 8cf806a..e73bf23 100644
--- a/lib/librte_vhost/vhost-net-cdev.c
+++ b/lib/librte_vhost/vhost-net-cdev.c
@@ -42,18 +42,18 @@
 #include <rte_ethdev.h>
 #include <rte_log.h>
 #include <rte_string_fns.h>
+#include <rte_virtio_net.h>
 
-#include "main.h"
 #include "vhost-net-cdev.h"
 
 #define FUSE_OPT_DUMMY 		"\0\0"
 #define FUSE_OPT_FORE 		"-f\0\0"
 #define FUSE_OPT_NOMULTI 	"-s\0\0"
 
-const uint32_t	default_major = 231;
-const uint32_t	default_minor = 1;
-const char		cuse_device_name[]	= "/dev/cuse";
-const char		default_cdev[] = "vhost-net";
+static const uint32_t	default_major = 231;
+static const uint32_t	default_minor = 1;
+static const char	cuse_device_name[]	= "/dev/cuse";
+static const char	default_cdev[] = "vhost-net";
 
 static struct fuse_session			*session;
 static struct vhost_net_device_ops	const *ops;
@@ -116,7 +116,7 @@ vhost_net_release(fuse_req_t req, struct fuse_file_info *fi)
 #define VHOST_IOCTL(func) do {								\
 	result = (func)(ctx);									\
 	fuse_reply_ioctl(req, result, NULL, 0);					\
-} while(0)													\
+} while(0)													
 
 /*
  * Boilerplate IOCTL RETRY
@@ -215,6 +215,7 @@ vhost_net_ioctl(fuse_req_t req, int cmd, void *arg,
 			break;
 
 		case VHOST_SET_MEM_TABLE:
+			/*TODO fix race condition.*/
 			LOG_DEBUG(VHOST_CONFIG, "(%"PRIu64") IOCTL: VHOST_SET_MEM_TABLE\n", ctx.fh);
 			static struct vhost_memory mem_temp;
 
@@ -302,7 +303,7 @@ static const struct cuse_lowlevel_ops vhost_net_ops = {
  * also passed when the device is registered in main.c.
  */
 int
-register_cuse_device(const char *base_name, int index, struct vhost_net_device_ops const * const pops)
+rte_vhost_driver_register(const char *dev_name)
 {
 	struct cuse_info cuse_info;
 	char device_name[PATH_MAX] = "";
@@ -321,16 +322,11 @@ register_cuse_device(const char *base_name, int index, struct vhost_net_device_o
 
 	/*
 	 * The device name is created. This is passed to QEMU so that it can register
-	 * the device with our application. The index allows us to have multiple instances
+	 * the device with our application. The dev_name allows us to have multiple instances
 	 * of userspace vhost which we can then add devices to separately.
 	 */
-	if (strncmp(base_name, default_cdev, PATH_MAX)!=0) {
-		snprintf(device_name, PATH_MAX, "DEVNAME=%s-%d", base_name, index);
-		snprintf(char_device_name, PATH_MAX, "/dev/%s-%d", base_name, index);
-	} else {
-		snprintf(device_name, PATH_MAX, "DEVNAME=%s", base_name);
-		snprintf(char_device_name, PATH_MAX, "/dev/%s", base_name);
-	}
+	snprintf(device_name, PATH_MAX, "DEVNAME=%s", dev_name);
+	snprintf(char_device_name, PATH_MAX, "/dev/%s", dev_name);
 
 	/* Check if device already exists. */
 	if (access(char_device_name, F_OK) != -1) {
@@ -340,12 +336,12 @@ register_cuse_device(const char *base_name, int index, struct vhost_net_device_o
 
 	memset(&cuse_info, 0, sizeof(cuse_info));
 	cuse_info.dev_major = default_major;
-	cuse_info.dev_minor = default_minor + index;
+	cuse_info.dev_minor = default_minor;
 	cuse_info.dev_info_argc = 1;
 	cuse_info.dev_info_argv = device_argv;
 	cuse_info.flags = CUSE_UNRESTRICTED_IOCTL;
 
-	ops = pops;
+	ops = get_virtio_net_callbacks();
 
 	session = cuse_lowlevel_setup(3, fuse_argv,
 				&cuse_info, &vhost_net_ops, 0, NULL);
@@ -355,11 +351,12 @@ register_cuse_device(const char *base_name, int index, struct vhost_net_device_o
 	return 0;
 }
 
-/*
+
+/**
  * The CUSE session is launched allowing the application to receive open, release and ioctl calls.
  */
 int
-start_cuse_session_loop(void)
+rte_vhost_driver_session_start(void)
 {
 	fuse_session_loop(session);
 
diff --git a/lib/librte_vhost/vhost-net-cdev.h b/lib/librte_vhost/vhost-net-cdev.h
index 575daa9..d9a5a9a 100644
--- a/lib/librte_vhost/vhost-net-cdev.h
+++ b/lib/librte_vhost/vhost-net-cdev.h
@@ -33,13 +33,45 @@
 
 #ifndef _VHOST_NET_CDEV_H_
 #define _VHOST_NET_CDEV_H_
-
+#include <stdint.h>
+#include <stdio.h>
+#include <sys/types.h>
+#include <unistd.h>
 #include <linux/vhost.h>
 
-struct vhost_memory;
-struct vhost_vring_state;
-struct vhost_vring_addr;
-struct vhost_vring_file;
+#include <rte_log.h>
+
+/* Macros for printing using RTE_LOG */
+#define RTE_LOGTYPE_VHOST_CONFIG RTE_LOGTYPE_USER1
+#define RTE_LOGTYPE_VHOST_DATA   RTE_LOGTYPE_USER1
+
+#ifdef RTE_LIBRTE_VHOST_DEBUG
+#define VHOST_MAX_PRINT_BUFF 6072
+#define LOG_LEVEL RTE_LOG_DEBUG
+#define LOG_DEBUG(log_type, fmt, args...) RTE_LOG(DEBUG, log_type, fmt, ##args)
+#define VHOST_PRINT_PACKET(device, addr, size, header) do { \
+	char *pkt_addr = (char *)(addr); \
+	unsigned int index; \
+	char packet[VHOST_MAX_PRINT_BUFF]; \
+	\
+	if ((header)) \
+		snprintf(packet, VHOST_MAX_PRINT_BUFF, "(%"PRIu64") Header size %d: ", (device->device_fh), (size)); \
+	else \
+		snprintf(packet, VHOST_MAX_PRINT_BUFF, "(%"PRIu64") Packet size %d: ", (device->device_fh), (size)); \
+	for (index = 0; index < (size); index++) { \
+		snprintf(packet + strnlen(packet, VHOST_MAX_PRINT_BUFF), VHOST_MAX_PRINT_BUFF - strnlen(packet, VHOST_MAX_PRINT_BUFF), \
+			"%02hhx ", pkt_addr[index]); \
+	} \
+	snprintf(packet + strnlen(packet, VHOST_MAX_PRINT_BUFF), VHOST_MAX_PRINT_BUFF - strnlen(packet, VHOST_MAX_PRINT_BUFF), "\n"); \
+	\
+	LOG_DEBUG(VHOST_DATA, "%s", packet); \
+} while (0)
+#else
+#define LOG_LEVEL RTE_LOG_INFO
+#define LOG_DEBUG(log_type, fmt, args...) do {} while (0)
+#define VHOST_PRINT_PACKET(device, addr, size, header) do {} while (0)
+#endif
+
 
 /*
  * Structure used to identify device context.
@@ -77,7 +109,6 @@ struct vhost_net_device_ops {
 	int (* reset_owner) 	(struct vhost_device_ctx);
 };
 
-int register_cuse_device(const char *base_name, int index, struct vhost_net_device_ops const * const);
-int start_cuse_session_loop(void);
 
+struct vhost_net_device_ops const *get_virtio_net_callbacks(void);
 #endif /* _VHOST_NET_CDEV_H_ */
diff --git a/lib/librte_vhost/vhost_rxtx.c b/lib/librte_vhost/vhost_rxtx.c
index 78fce0d..0d96c43 100644
--- a/lib/librte_vhost/vhost_rxtx.c
+++ b/lib/librte_vhost/vhost_rxtx.c
@@ -40,17 +40,17 @@
 
 #include "vhost-net-cdev.h"
 
-#define MAX_PKT_BURST 64
-#define MAX_MRG_PKT_BURST 64
+#define VHOST_MAX_PKT_BURST 64
+#define VHOST_MAX_MRG_PKT_BURST 64
 
-/*
+/**
  * This function adds buffers to the virtio devices RX virtqueue. Buffers can
  * be received from the physical port or from another virtio device. A packet
  * count is returned to indicate the number of packets that were succesfully
  * added to the RX queue. This function works when mergeable is disabled.
  */
-static inline uint32_t __attribute__((always_inline))
-virtio_dev_rx(struct virtio_net *dev, struct rte_mbuf **pkts, uint32_t count)
+uint32_t
+rte_vhost_enqueue_burst(struct virtio_net *dev, uint16_t queue_id, struct rte_mbuf **pkts, uint32_t count)
 {
 	struct vhost_virtqueue *vq;
 	struct vring_desc *desc;
@@ -59,36 +59,28 @@ virtio_dev_rx(struct virtio_net *dev, struct rte_mbuf **pkts, uint32_t count)
 	struct virtio_net_hdr_mrg_rxbuf virtio_hdr = {{0,0,0,0,0,0},0};
 	uint64_t buff_addr = 0;
 	uint64_t buff_hdr_addr = 0;
-	uint32_t head[MAX_PKT_BURST], packet_len = 0;
+	uint32_t head[VHOST_MAX_PKT_BURST], packet_len = 0;
 	uint32_t head_idx, packet_success = 0;
-	uint32_t retry = 0;
+	uint32_t mergeable, mrg_count = 0;
 	uint16_t avail_idx, res_cur_idx;
 	uint16_t res_base_idx, res_end_idx;
 	uint16_t free_entries;
 	uint8_t success = 0;
 
 	LOG_DEBUG(VHOST_DATA, "(%"PRIu64") virtio_dev_rx()\n", dev->device_fh);
-	vq = dev->virtqueue[VIRTIO_RXQ];
-	count = (count > MAX_PKT_BURST) ? MAX_PKT_BURST : count;
+	if (unlikely(queue_id != VIRTIO_RXQ)) {
+		LOG_DEBUG(VHOST_DATA, "mq isn't supported in this version.\n");
+		return 0;
+	}
 
+	vq = dev->virtqueue[VIRTIO_RXQ];
+	count = (count > VHOST_MAX_PKT_BURST) ? VHOST_MAX_PKT_BURST : count;
 	/* As many data cores may want access to available buffers, they need to be reserved. */
 	do {
 		res_base_idx = vq->last_used_idx_res;
 		avail_idx = *((volatile uint16_t *)&vq->avail->idx);
 
 		free_entries = (avail_idx - res_base_idx);
-		/* If retry is enabled and the queue is full then we wait and retry to avoid packet loss. */
-		if (enable_retry && unlikely(count > free_entries)) {
-			for (retry = 0; retry < burst_rx_retry_num; retry++) {
-				rte_delay_us(burst_rx_delay_time);
-				avail_idx =
-					*((volatile uint16_t *)&vq->avail->idx);
-				free_entries = (avail_idx - res_base_idx);
-				if (count <= free_entries)
-					break;
-			}
-		}
-
 		/*check that we have enough buffers*/
 		if (unlikely(count > free_entries))
 			count = free_entries;
@@ -98,8 +90,10 @@ virtio_dev_rx(struct virtio_net *dev, struct rte_mbuf **pkts, uint32_t count)
 
 		res_end_idx = res_base_idx + count;
 		/* vq->last_used_idx_res is atomically updated. */
-		success = rte_atomic16_cmpset(&vq->last_used_idx_res, res_base_idx,
-									res_end_idx);
+		/* TODO: Allow to disable cmpset if no concurrency in application */
+		success = rte_atomic16_cmpset(&vq->last_used_idx_res,
+				res_base_idx, res_end_idx);
+		/* If there is contention here and failed, try again. */
 	} while (unlikely(success == 0));
 	res_cur_idx = res_base_idx;
 	LOG_DEBUG(VHOST_DATA, "(%"PRIu64") Current Index %d| End Index %d\n", dev->device_fh, res_cur_idx, res_end_idx);
@@ -107,6 +101,9 @@ virtio_dev_rx(struct virtio_net *dev, struct rte_mbuf **pkts, uint32_t count)
 	/* Prefetch available ring to retrieve indexes. */
 	rte_prefetch0(&vq->avail->ring[res_cur_idx & (vq->size - 1)]);
 
+	/* Check if the VIRTIO_NET_F_MRG_RXBUF feature is enabled. */
+	mergeable = dev->features & (1 << VIRTIO_NET_F_MRG_RXBUF);
+
 	/* Retrieve all of the head indexes first to avoid caching issues. */
 	for (head_idx = 0; head_idx < count; head_idx++)
 		head[head_idx] = vq->avail->ring[(res_cur_idx + head_idx) & (vq->size - 1)];
@@ -125,44 +122,60 @@ virtio_dev_rx(struct virtio_net *dev, struct rte_mbuf **pkts, uint32_t count)
 		/* Prefetch buffer address. */
 		rte_prefetch0((void*)(uintptr_t)buff_addr);
 
-		/* Copy virtio_hdr to packet and increment buffer address */
-		buff_hdr_addr = buff_addr;
-		packet_len = rte_pktmbuf_data_len(buff) + vq->vhost_hlen;
-
-		/*
-		 * If the descriptors are chained the header and data are
-		 * placed in separate buffers.
-		 */
-		if (desc->flags & VRING_DESC_F_NEXT) {
-			desc->len = vq->vhost_hlen;
-			desc = &vq->desc[desc->next];
-			/* Buffer address translation. */
-			buff_addr = gpa_to_vva(dev, desc->addr);
-			desc->len = rte_pktmbuf_data_len(buff);
+		if (mergeable && (mrg_count != 0)) {
+			desc->len = packet_len = rte_pktmbuf_data_len(buff);
 		} else {
-			buff_addr += vq->vhost_hlen;
-			desc->len = packet_len;
+			/* Copy virtio_hdr to packet and increment buffer address */
+			buff_hdr_addr = buff_addr;
+			packet_len = rte_pktmbuf_data_len(buff) + vq->vhost_hlen;
+
+			/*
+			 * If the descriptors are chained the header and data are placed in
+			 * separate buffers.
+			 */
+			if (desc->flags & VRING_DESC_F_NEXT) {
+				desc->len = vq->vhost_hlen;
+				desc = &vq->desc[desc->next];
+				/* Buffer address translation. */
+				buff_addr = gpa_to_vva(dev, desc->addr);
+				desc->len = rte_pktmbuf_data_len(buff);
+			} else {
+				buff_addr += vq->vhost_hlen;
+				desc->len = packet_len;
+			}
 		}
 
+
 		/* Update used ring with desc information */
 		vq->used->ring[res_cur_idx & (vq->size - 1)].id = head[packet_success];
 		vq->used->ring[res_cur_idx & (vq->size - 1)].len = packet_len;
 
 		/* Copy mbuf data to buffer */
+		/* TODO fixme for sg mbuf and the case that desc couldn't hold the mbuf data */
 		rte_memcpy((void *)(uintptr_t)buff_addr,
 			(const void *)buff->pkt.data,
 			rte_pktmbuf_data_len(buff));
-		PRINT_PACKET(dev, (uintptr_t)buff_addr,
+		VHOST_PRINT_PACKET(dev, (uintptr_t)buff_addr,
 			rte_pktmbuf_data_len(buff), 0);
 
 		res_cur_idx++;
 		packet_success++;
-
-		rte_memcpy((void *)(uintptr_t)buff_hdr_addr,
-			(const void *)&virtio_hdr, vq->vhost_hlen);
-
-		PRINT_PACKET(dev, (uintptr_t)buff_hdr_addr, vq->vhost_hlen, 1);
-
+	
+		/* If mergeable is disabled then a header is required per buffer. */
+		if (!mergeable) {
+			rte_memcpy((void *)(uintptr_t)buff_hdr_addr, (const void *)&virtio_hdr, vq->vhost_hlen);
+			VHOST_PRINT_PACKET(dev, (uintptr_t)buff_hdr_addr, vq->vhost_hlen, 1);
+		} else {
+			mrg_count++;
+			/* Merge buffer can only handle so many buffers at a time. Tell the guest if this limit is reached. */
+			if ((mrg_count == VHOST_MAX_MRG_PKT_BURST) || (res_cur_idx == res_end_idx)) {
+				virtio_hdr.num_buffers = mrg_count;
+				LOG_DEBUG(VHOST_DATA, "(%"PRIu64") RX: Num merge buffers %d\n", dev->device_fh, virtio_hdr.num_buffers);
+				rte_memcpy((void *)(uintptr_t)buff_hdr_addr, (const void *)&virtio_hdr, vq->vhost_hlen);
+				VHOST_PRINT_PACKET(dev, (uintptr_t)buff_hdr_addr, vq->vhost_hlen, 1);
+				mrg_count = 0;
+			}
+		}
 		if (res_cur_idx < res_end_idx) {
 			/* Prefetch descriptor index. */
 			rte_prefetch0(&vq->desc[head[packet_success]]);
@@ -185,25 +198,30 @@ virtio_dev_rx(struct virtio_net *dev, struct rte_mbuf **pkts, uint32_t count)
 }
 
 
-static inline void __attribute__((always_inline))
-virtio_dev_tx(struct virtio_net* dev, struct rte_mempool *mbuf_pool)
+uint32_t
+rte_vhost_dequeue_burst(struct virtio_net *dev, uint16_t queue_id, struct rte_mempool *mbuf_pool, struct rte_mbuf **pkts, uint32_t count)
 {
-	struct rte_mbuf m;
+	struct rte_mbuf *mbuf;
 	struct vhost_virtqueue *vq;
 	struct vring_desc *desc;
 	uint64_t buff_addr = 0;
-	uint32_t head[MAX_PKT_BURST];
+	uint32_t head[VHOST_MAX_PKT_BURST];
 	uint32_t used_idx;
 	uint32_t i;
 	uint16_t free_entries, packet_success = 0;
 	uint16_t avail_idx;
 
+	if (unlikely(queue_id != VIRTIO_TXQ)) {
+		LOG_DEBUG(VHOST_DATA, "mq isn't supported in this version.\n");
+		return 0;
+	}
+
 	vq = dev->virtqueue[VIRTIO_TXQ];
 	avail_idx =  *((volatile uint16_t *)&vq->avail->idx);
 
 	/* If there are no available buffers then return. */
 	if (vq->last_used_idx == avail_idx)
-		return;
+		return 0;
 
 	LOG_DEBUG(VHOST_DATA, "(%"PRIu64") virtio_dev_tx()\n", dev->device_fh);
 
@@ -213,9 +231,11 @@ virtio_dev_tx(struct virtio_net* dev, struct rte_mempool *mbuf_pool)
 	/*get the number of free entries in the ring*/
 	free_entries = (avail_idx - vq->last_used_idx);
 
+	if (free_entries > count)
+		free_entries = count;
 	/* Limit to MAX_PKT_BURST. */
-	if (free_entries > MAX_PKT_BURST)
-		free_entries = MAX_PKT_BURST;
+	if (free_entries > VHOST_MAX_PKT_BURST)
+		free_entries = VHOST_MAX_PKT_BURST;
 
 	LOG_DEBUG(VHOST_DATA, "(%"PRIu64") Buffers available %d\n", dev->device_fh, free_entries);
 	/* Retrieve all of the head indexes first to avoid caching issues. */
@@ -249,23 +269,20 @@ virtio_dev_tx(struct virtio_net* dev, struct rte_mempool *mbuf_pool)
 		vq->used->ring[used_idx].id = head[packet_success];
 		vq->used->ring[used_idx].len = 0;
 
-		/* Setup dummy mbuf. This is copied to a real mbuf if transmitted out the physical port. */
-		m.pkt.data_len = desc->len;
-		m.pkt.pkt_len = desc->len;
-		m.pkt.data = (void*)(uintptr_t)buff_addr;
+		mbuf = rte_pktmbuf_alloc(mbuf_pool);
+		if (unlikely(mbuf == NULL)) {
+			RTE_LOG(ERR, VHOST_DATA, "Failed to allocate memory for mbuf.\n");
+			return packet_success;
+		}
+		mbuf->pkt.data_len = desc->len;
+		mbuf->pkt.pkt_len  = mbuf->pkt.data_len;
+
+		rte_memcpy((void *) mbuf->pkt.data,
+			(const void *) buff_addr, mbuf->pkt.data_len);
 
-		PRINT_PACKET(dev, (uintptr_t)buff_addr, desc->len, 0);
+		pkts[packet_success] = mbuf;
 
-		/* If this is the first received packet we need to learn the MAC and setup VMDQ */
-		if (dev->ready == DEVICE_MAC_LEARNING) {
-			if (dev->remove || (link_vmdq(dev, &m) == -1)) {
-				/*discard frame if device is scheduled for removal or a duplicate MAC address is found. */
-				packet_success += free_entries;
-				vq->last_used_idx += packet_success;
-				break;
-			}
-		}
-		virtio_tx_route(dev, &m, mbuf_pool, (uint16_t)dev->device_fh);
+		VHOST_PRINT_PACKET(dev, (uintptr_t)buff_addr, desc->len, 0);
 
 		vq->last_used_idx++;
 		packet_success++;
@@ -276,6 +293,6 @@ virtio_dev_tx(struct virtio_net* dev, struct rte_mempool *mbuf_pool)
 	/* Kick guest if required. */
 	if (!(vq->avail->flags & VRING_AVAIL_F_NO_INTERRUPT))
 		eventfd_write((int)vq->kickfd, 1);
-}
-
 
+	return packet_success;
+}
diff --git a/lib/librte_vhost/virtio-net.c b/lib/librte_vhost/virtio-net.c
index 5e659c7..9852961 100644
--- a/lib/librte_vhost/virtio-net.c
+++ b/lib/librte_vhost/virtio-net.c
@@ -47,27 +47,32 @@
 #include <rte_log.h>
 #include <rte_string_fns.h>
 #include <rte_memory.h>
+#include <rte_virtio_net.h>
 
-#include "main.h"
-#include "virtio-net.h"
 #include "vhost-net-cdev.h"
 #include "eventfd_link/eventfd_link.h"
 
-const char eventfd_cdev[] = "/dev/eventfd-link";
+/**
+ * Device linked list structure for configuration.
+ */
+struct virtio_net_config_ll {
+	struct virtio_net             dev;    /* Virtio device. */
+	struct virtio_net_config_ll   *next;  /* Next entry on linked list. */
+};
 
-extern uint32_t num_devices;
-static uint32_t num_cur_devices = 0;
+static const char eventfd_cdev[] = "/dev/eventfd-link";
 
 /* device ops to add/remove device to data core. */
 static struct virtio_net_device_ops const * notify_ops;
 /* Root address of the linked list in the configuration core. */
 static struct virtio_net_config_ll			*ll_root = NULL;
 
-/* Features supported by this application. RX merge buffers are disabled by default. */
-uint64_t VHOST_FEATURES = (0ULL << VIRTIO_NET_F_MRG_RXBUF);
+/* Features supported by this library. */
+#define VHOST_SUPPORTED_FEATURES (1ULL << VIRTIO_NET_F_MRG_RXBUF)
+static uint64_t VHOST_FEATURES = VHOST_SUPPORTED_FEATURES;
 
 /* Line size for reading maps file. */
-const uint32_t BUFSIZE = PATH_MAX;
+static const uint32_t BUFSIZE = PATH_MAX;
 
 /* Size of prot char array in procmap. */
 #define PROT_SZ 5
@@ -347,8 +352,6 @@ cleanup_device(struct virtio_net *dev)
 	/* Unmap QEMU memory file if mapped. */
 	if (dev->mem) {
 		munmap((void*)(uintptr_t)dev->mem->mapped_address, (size_t)dev->mem->mapped_size);
-		if (dev->mem->regions_hpa)
-			free(dev->mem->regions_hpa);
 		free(dev->mem);
 	}
 
@@ -434,12 +437,6 @@ new_device(struct vhost_device_ctx ctx)
 	struct virtio_net_config_ll *new_ll_dev;
 	struct vhost_virtqueue *virtqueue_rx, *virtqueue_tx;
 
-	/*check the number of devices in the system*/
-	if (num_cur_devices == num_devices) {
-		RTE_LOG(ERR, VHOST_CONFIG, "() Max num devices (%u) exceeded\n", num_devices);
-		return -1;
-	}
-
 	/* Setup device and virtqueues. */
 	new_ll_dev = malloc(sizeof(struct virtio_net_config_ll));
 	if (new_ll_dev == NULL) {
@@ -473,9 +470,6 @@ new_device(struct vhost_device_ctx ctx)
 	/* Add entry to device configuration linked list. */
 	add_config_ll_entry(new_ll_dev);
 
-	/*increment the number of devices in the system*/
-	num_cur_devices++;
-
 	return new_ll_dev->dev.device_fh;
 }
 
@@ -506,9 +500,6 @@ destroy_device(struct vhost_device_ctx ctx)
 			ll_dev_cur = ll_dev_cur->next;
 		}
 	}
-
-	/*decrement the number of devices in the system*/
-	num_cur_devices--;
 }
 
 /*
@@ -592,153 +583,6 @@ set_features(struct vhost_device_ctx ctx, uint64_t *pu)
 	return 0;
 }
 
-/*
- * Calculate the region count of physical continous regions for one particular
- * region of whose vhost virtual address is continous. The particular region
- * start from vva_start, with size of 'size' in argument.
- */
-static uint32_t check_hpa_regions(uint64_t vva_start, uint64_t size)
-{
-	uint32_t i, nregions = 0, page_size = PAGE_SIZE;
-	uint64_t cur_phys_addr = 0, next_phys_addr = 0;
-	if (vva_start % page_size) {
-		LOG_DEBUG(VHOST_CONFIG,
-			"in check_countinous: vva start(%p) mod page_size(%d) "
-			"has remainder\n",
-			(void *)(uintptr_t)vva_start, page_size);
-		return 0;
-	}
-	if (size % page_size) {
-		LOG_DEBUG(VHOST_CONFIG,
-			"in check_countinous: "
-			"size((%"PRIu64")) mod page_size(%d) has remainder\n",
-			size, page_size);
-		return 0;
-	}
-	for (i = 0; i < size - page_size; i = i + page_size) {
-		cur_phys_addr
-			= rte_mem_virt2phy((void *)(uintptr_t)(vva_start + i));
-		next_phys_addr = rte_mem_virt2phy(
-			(void *)(uintptr_t)(vva_start + i + page_size));
-		if ((cur_phys_addr + page_size) != next_phys_addr) {
-			++nregions;
-			LOG_DEBUG(VHOST_CONFIG,
-				"in check_continuous: hva addr:(%p) is not "
-				"continuous with hva addr:(%p), diff:%d\n",
-				(void *)(uintptr_t)(vva_start + (uint64_t)i),
-				(void *)(uintptr_t)(vva_start + (uint64_t)i
-				+ page_size), page_size);
-			LOG_DEBUG(VHOST_CONFIG,
-				"in check_continuous: hpa addr:(%p) is not "
-				"continuous with hpa addr:(%p), "
-				"diff:(%"PRIu64")\n",
-				(void *)(uintptr_t)cur_phys_addr,
-				(void *)(uintptr_t)next_phys_addr,
-				(next_phys_addr-cur_phys_addr));
-		}
-	}
-	return nregions;
-}
-
-/*
- * Divide each region whose vhost virtual address is continous into a few
- * sub-regions, make sure the physical address within each sub-region are
- * continous. And fill offset(to GPA) and size etc. information of each
- * sub-region into regions_hpa.
- */
-static uint32_t fill_hpa_memory_regions(void *memory)
-{
-	uint32_t regionidx, regionidx_hpa = 0, i, k, page_size = PAGE_SIZE;
-	uint64_t cur_phys_addr = 0, next_phys_addr = 0, vva_start;
-	struct virtio_memory *virtio_memory = (struct virtio_memory *)memory;
-	struct virtio_memory_regions_hpa *mem_region_hpa
-		= virtio_memory->regions_hpa;
-
-	if (mem_region_hpa == NULL)
-		return 0;
-
-	for (regionidx = 0; regionidx < virtio_memory->nregions; regionidx++) {
-		vva_start = virtio_memory->regions[regionidx].guest_phys_address
-			+ virtio_memory->regions[regionidx].address_offset;
-		mem_region_hpa[regionidx_hpa].guest_phys_address
-			= virtio_memory->regions[regionidx].guest_phys_address;
-		mem_region_hpa[regionidx_hpa].host_phys_addr_offset =
-			rte_mem_virt2phy((void *)(uintptr_t)(vva_start))
-			- mem_region_hpa[regionidx_hpa].guest_phys_address;
-		LOG_DEBUG(VHOST_CONFIG,
-			"in fill_hpa_regions: guest phys addr start[%d]:(%p)\n",
-			regionidx_hpa,
-			(void *)(uintptr_t)
-			(mem_region_hpa[regionidx_hpa].guest_phys_address));
-		LOG_DEBUG(VHOST_CONFIG,
-			"in fill_hpa_regions: host  phys addr start[%d]:(%p)\n",
-			regionidx_hpa,
-			(void *)(uintptr_t)
-			(mem_region_hpa[regionidx_hpa].host_phys_addr_offset));
-		for (i = 0, k = 0;
-			i < virtio_memory->regions[regionidx].memory_size
-				- page_size;
-			i += page_size) {
-			cur_phys_addr = rte_mem_virt2phy(
-					(void *)(uintptr_t)(vva_start + i));
-			next_phys_addr = rte_mem_virt2phy(
-					(void *)(uintptr_t)(vva_start
-					+ i + page_size));
-			if ((cur_phys_addr + page_size) != next_phys_addr) {
-				mem_region_hpa[regionidx_hpa].guest_phys_address_end =
-					mem_region_hpa[regionidx_hpa].guest_phys_address
-					+ k + page_size;
-				mem_region_hpa[regionidx_hpa].memory_size
-					= k + page_size;
-				LOG_DEBUG(VHOST_CONFIG, "in fill_hpa_regions: guest "
-					"phys addr end  [%d]:(%p)\n",
-					regionidx_hpa,
-					(void *)(uintptr_t)
-					(mem_region_hpa[regionidx_hpa].guest_phys_address_end));
-				LOG_DEBUG(VHOST_CONFIG,
-					"in fill_hpa_regions: guest phys addr "
-					"size [%d]:(%p)\n",
-					regionidx_hpa,
-					(void *)(uintptr_t)
-					(mem_region_hpa[regionidx_hpa].memory_size));
-				mem_region_hpa[regionidx_hpa + 1].guest_phys_address
-					= mem_region_hpa[regionidx_hpa].guest_phys_address_end;
-				++regionidx_hpa;
-				mem_region_hpa[regionidx_hpa].host_phys_addr_offset =
-					next_phys_addr
-					- mem_region_hpa[regionidx_hpa].guest_phys_address;
-				LOG_DEBUG(VHOST_CONFIG, "in fill_hpa_regions: guest"
-					" phys addr start[%d]:(%p)\n",
-					regionidx_hpa,
-					(void *)(uintptr_t)
-					(mem_region_hpa[regionidx_hpa].guest_phys_address));
-				LOG_DEBUG(VHOST_CONFIG,
-					"in fill_hpa_regions: host  phys addr "
-					"start[%d]:(%p)\n",
-					regionidx_hpa,
-					(void *)(uintptr_t)
-					(mem_region_hpa[regionidx_hpa].host_phys_addr_offset));
-				k = 0;
-			} else {
-				k += page_size;
-			}
-		}
-		mem_region_hpa[regionidx_hpa].guest_phys_address_end
-			= mem_region_hpa[regionidx_hpa].guest_phys_address
-			+ k + page_size;
-		mem_region_hpa[regionidx_hpa].memory_size = k + page_size;
-		LOG_DEBUG(VHOST_CONFIG, "in fill_hpa_regions: guest phys addr end  "
-			"[%d]:(%p)\n", regionidx_hpa,
-			(void *)(uintptr_t)
-			(mem_region_hpa[regionidx_hpa].guest_phys_address_end));
-		LOG_DEBUG(VHOST_CONFIG, "in fill_hpa_regions: guest phys addr size "
-			"[%d]:(%p)\n", regionidx_hpa,
-			(void *)(uintptr_t)
-			(mem_region_hpa[regionidx_hpa].memory_size));
-		++regionidx_hpa;
-	}
-	return regionidx_hpa;
-}
 
 /*
  * Called from CUSE IOCTL: VHOST_SET_MEM_TABLE
@@ -832,7 +676,6 @@ set_mem_table(struct vhost_device_ctx ctx, const void *mem_regions_addr, uint32_
 		}
 	}
 	mem->nregions = valid_regions;
-	mem->nregions_hpa = mem->nregions;
 	dev->mem = mem;
 
 	/*
@@ -843,34 +686,7 @@ set_mem_table(struct vhost_device_ctx ctx, const void *mem_regions_addr, uint32_
 		dev->mem->regions[regionidx].address_offset = dev->mem->regions[regionidx].userspace_address - dev->mem->base_address
 			+ dev->mem->mapped_address - dev->mem->regions[regionidx].guest_phys_address;
 
-		dev->mem->nregions_hpa
-			+= check_hpa_regions(
-				dev->mem->regions[regionidx].guest_phys_address
-				+ dev->mem->regions[regionidx].address_offset,
-				dev->mem->regions[regionidx].memory_size);
-	}
-	if (dev->mem->regions_hpa != NULL) {
-		free(dev->mem->regions_hpa);
-		dev->mem->regions_hpa = NULL;
 	}
-
-	dev->mem->regions_hpa = (struct virtio_memory_regions_hpa *) calloc(1,
-		(sizeof(struct virtio_memory_regions_hpa)
-		* dev->mem->nregions_hpa));
-	if (dev->mem->regions_hpa == NULL) {
-		RTE_LOG(ERR, VHOST_CONFIG,
-			"(%"PRIu64") Failed to allocate memory for "
-			"dev->mem->regions_hpa.\n", dev->device_fh);
-		return -1;
-	}
-	if (fill_hpa_memory_regions(
-		(void *)dev->mem) != dev->mem->nregions_hpa) {
-		RTE_LOG(ERR, VHOST_CONFIG,
-			"in set_mem_table: hpa memory regions number mismatch: "
-			"[%d]\n", dev->mem->nregions_hpa);
-		return -1;
-	}
-
 	return 0;
 }
 
@@ -1144,22 +960,45 @@ get_virtio_net_callbacks(void)
 	return &vhost_device_ops;
 }
 
-/*
- * Register ops so that we can add/remove device to data core.
- */
-int
-init_virtio_net(struct virtio_net_device_ops const * const ops)
+int rte_vhost_enable_guest_notification(struct virtio_net *dev, uint16_t queue_id, int enable)
 {
-	notify_ops = ops;
+	if (enable) {
+		RTE_LOG(ERR, VHOST_CONFIG, "guest notification isn't supported.\n");
+		return -1;
+	}
 
+	dev->virtqueue[queue_id]->used->flags = enable ? 0 : VRING_USED_F_NO_NOTIFY;
 	return 0;
 }
 
+uint64_t rte_vhost_feature_get(void)
+{
+	return VHOST_FEATURES;
+}
+
+int rte_vhost_feature_disable(uint64_t feature_mask)
+{
+	VHOST_FEATURES = VHOST_FEATURES & ~feature_mask;
+	return 0;
+}
+
+int rte_vhost_feature_enable(uint64_t feature_mask)
+{
+	if ((feature_mask & VHOST_SUPPORTED_FEATURES) == feature_mask) {
+		VHOST_FEATURES = VHOST_FEATURES | feature_mask;
+		return 0;
+	}
+	return -1;
+}
+
+
 /*
- * Currently not used as we Ctrl+c to exit application.
+ * Register ops so that we can add/remove device to data core.
  */
 int
-deinit_virtio_net(void)
+rte_vhost_driver_callback_register(struct virtio_net_device_ops const * const ops)
 {
+	notify_ops = ops;
+
 	return 0;
 }
-- 
1.8.1.4

^ permalink raw reply	[flat|nested] 23+ messages in thread

* [dpdk-dev] [PATCH v5 04/11] lib/librte_vhost: merge vhost merge-able rx. merge vhost tx fix.
  2014-09-26  9:45 [dpdk-dev] [PATCH v5 00/11] user space vhost library and vhost example Huawei Xie
                   ` (2 preceding siblings ...)
  2014-09-26  9:45 ` [dpdk-dev] [PATCH v5 03/11] lib/librte_vhost: vhost lib transform Huawei Xie
@ 2014-09-26  9:45 ` Huawei Xie
  2014-09-26  9:45 ` [dpdk-dev] [PATCH v5 05/11] lib/librte_vhost: merge Oliver's mbuf change Huawei Xie
                   ` (6 subsequent siblings)
  10 siblings, 0 replies; 23+ messages in thread
From: Huawei Xie @ 2014-09-26  9:45 UTC (permalink / raw)
  To: dev

Merge vhost merge-able rx.
For vhost tx, previous vhost merge-able feature introduces virtio_dev_merge_tx,
and calls virtio_dev_tx and vritio_dev_merge_tx respectively depends on whether
the vhost device supports merge-able feature.
There is no so called merge-tx, it is actually fix for memcpy from chained vring
desc to chained mbuf.
Use virtio_dev_merge_tx as the base for vhost tx.

Signed-off-by: Huawei Xie <huawei.xie@intel.com>
---
 lib/librte_vhost/rte_virtio_net.h |  16 +-
 lib/librte_vhost/vhost_rxtx.c     | 568 +++++++++++++++++++++++++++++++++-----
 2 files changed, 511 insertions(+), 73 deletions(-)

diff --git a/lib/librte_vhost/rte_virtio_net.h b/lib/librte_vhost/rte_virtio_net.h
index 08dc6f4..99ddfc1 100644
--- a/lib/librte_vhost/rte_virtio_net.h
+++ b/lib/librte_vhost/rte_virtio_net.h
@@ -53,9 +53,18 @@
 /* Enum for virtqueue management. */
 enum {VIRTIO_RXQ, VIRTIO_TXQ, VIRTIO_QNUM};
 
-
-/*
- * Structure contains variables relevant to TX/RX virtqueues.
+#define BUF_VECTOR_MAX 256
+/**
+ * Structure contains buffer address, length and descriptor index
+ * from vring to do scatter RX.
+ */
+struct buf_vector {
+	uint64_t buf_addr;
+	uint32_t buf_len;
+	uint32_t desc_idx;
+};
+/**
+ * Structure contains variables relevant to RX/TX virtqueues.
  */
 struct vhost_virtqueue
 {
@@ -69,6 +78,7 @@ struct vhost_virtqueue
 	volatile uint16_t	last_used_idx_res;	/* Used for multiple devices reserving buffers. */
 	eventfd_t			callfd;				/* Currently unused as polling mode is enabled. */
 	eventfd_t			kickfd;				/* Used to notify the guest (trigger interrupt). */
+	struct buf_vector    buf_vec[BUF_VECTOR_MAX]; /**< for scatter RX. */
 } __rte_cache_aligned;
 
 
diff --git a/lib/librte_vhost/vhost_rxtx.c b/lib/librte_vhost/vhost_rxtx.c
index 0d96c43..81368e6 100644
--- a/lib/librte_vhost/vhost_rxtx.c
+++ b/lib/librte_vhost/vhost_rxtx.c
@@ -49,8 +49,8 @@
  * count is returned to indicate the number of packets that were succesfully
  * added to the RX queue. This function works when mergeable is disabled.
  */
-uint32_t
-rte_vhost_enqueue_burst(struct virtio_net *dev, uint16_t queue_id, struct rte_mbuf **pkts, uint32_t count)
+static inline uint32_t __attribute__((always_inline))
+virtio_dev_rx(struct virtio_net *dev, uint16_t queue_id, struct rte_mbuf **pkts, uint32_t count)
 {
 	struct vhost_virtqueue *vq;
 	struct vring_desc *desc;
@@ -61,7 +61,6 @@ rte_vhost_enqueue_burst(struct virtio_net *dev, uint16_t queue_id, struct rte_mb
 	uint64_t buff_hdr_addr = 0;
 	uint32_t head[VHOST_MAX_PKT_BURST], packet_len = 0;
 	uint32_t head_idx, packet_success = 0;
-	uint32_t mergeable, mrg_count = 0;
 	uint16_t avail_idx, res_cur_idx;
 	uint16_t res_base_idx, res_end_idx;
 	uint16_t free_entries;
@@ -101,9 +100,6 @@ rte_vhost_enqueue_burst(struct virtio_net *dev, uint16_t queue_id, struct rte_mb
 	/* Prefetch available ring to retrieve indexes. */
 	rte_prefetch0(&vq->avail->ring[res_cur_idx & (vq->size - 1)]);
 
-	/* Check if the VIRTIO_NET_F_MRG_RXBUF feature is enabled. */
-	mergeable = dev->features & (1 << VIRTIO_NET_F_MRG_RXBUF);
-
 	/* Retrieve all of the head indexes first to avoid caching issues. */
 	for (head_idx = 0; head_idx < count; head_idx++)
 		head[head_idx] = vq->avail->ring[(res_cur_idx + head_idx) & (vq->size - 1)];
@@ -122,27 +118,23 @@ rte_vhost_enqueue_burst(struct virtio_net *dev, uint16_t queue_id, struct rte_mb
 		/* Prefetch buffer address. */
 		rte_prefetch0((void*)(uintptr_t)buff_addr);
 
-		if (mergeable && (mrg_count != 0)) {
-			desc->len = packet_len = rte_pktmbuf_data_len(buff);
+		/* Copy virtio_hdr to packet and increment buffer address */
+		buff_hdr_addr = buff_addr;
+		packet_len = rte_pktmbuf_data_len(buff) + vq->vhost_hlen;
+
+		/*
+		 * If the descriptors are chained the header and data are placed in
+		 * separate buffers.
+		 */
+		if (desc->flags & VRING_DESC_F_NEXT) {
+			desc->len = vq->vhost_hlen;
+			desc = &vq->desc[desc->next];
+			/* Buffer address translation. */
+			buff_addr = gpa_to_vva(dev, desc->addr);
+			desc->len = rte_pktmbuf_data_len(buff);
 		} else {
-			/* Copy virtio_hdr to packet and increment buffer address */
-			buff_hdr_addr = buff_addr;
-			packet_len = rte_pktmbuf_data_len(buff) + vq->vhost_hlen;
-
-			/*
-			 * If the descriptors are chained the header and data are placed in
-			 * separate buffers.
-			 */
-			if (desc->flags & VRING_DESC_F_NEXT) {
-				desc->len = vq->vhost_hlen;
-				desc = &vq->desc[desc->next];
-				/* Buffer address translation. */
-				buff_addr = gpa_to_vva(dev, desc->addr);
-				desc->len = rte_pktmbuf_data_len(buff);
-			} else {
-				buff_addr += vq->vhost_hlen;
-				desc->len = packet_len;
-			}
+			buff_addr += vq->vhost_hlen;
+			desc->len = packet_len;
 		}
 
 
@@ -161,21 +153,9 @@ rte_vhost_enqueue_burst(struct virtio_net *dev, uint16_t queue_id, struct rte_mb
 		res_cur_idx++;
 		packet_success++;
 	
-		/* If mergeable is disabled then a header is required per buffer. */
-		if (!mergeable) {
-			rte_memcpy((void *)(uintptr_t)buff_hdr_addr, (const void *)&virtio_hdr, vq->vhost_hlen);
-			VHOST_PRINT_PACKET(dev, (uintptr_t)buff_hdr_addr, vq->vhost_hlen, 1);
-		} else {
-			mrg_count++;
-			/* Merge buffer can only handle so many buffers at a time. Tell the guest if this limit is reached. */
-			if ((mrg_count == VHOST_MAX_MRG_PKT_BURST) || (res_cur_idx == res_end_idx)) {
-				virtio_hdr.num_buffers = mrg_count;
-				LOG_DEBUG(VHOST_DATA, "(%"PRIu64") RX: Num merge buffers %d\n", dev->device_fh, virtio_hdr.num_buffers);
-				rte_memcpy((void *)(uintptr_t)buff_hdr_addr, (const void *)&virtio_hdr, vq->vhost_hlen);
-				VHOST_PRINT_PACKET(dev, (uintptr_t)buff_hdr_addr, vq->vhost_hlen, 1);
-				mrg_count = 0;
-			}
-		}
+		rte_memcpy((void *)(uintptr_t)buff_hdr_addr, (const void *)&virtio_hdr,
+				vq->vhost_hlen);
+		VHOST_PRINT_PACKET(dev, (uintptr_t)buff_hdr_addr, vq->vhost_hlen, 1);
 		if (res_cur_idx < res_end_idx) {
 			/* Prefetch descriptor index. */
 			rte_prefetch0(&vq->desc[head[packet_success]]);
@@ -197,18 +177,357 @@ rte_vhost_enqueue_burst(struct virtio_net *dev, uint16_t queue_id, struct rte_mb
 	return count;
 }
 
+static inline uint32_t __attribute__((always_inline))
+copy_from_mbuf_to_vring(struct virtio_net *dev, uint16_t res_base_idx,
+	uint16_t res_end_idx, struct rte_mbuf *pkt)
+{
+	uint32_t vec_idx = 0;
+	uint32_t entry_success = 0;
+	struct vhost_virtqueue *vq;
+	/* The virtio_hdr is initialised to 0. */
+	struct virtio_net_hdr_mrg_rxbuf virtio_hdr = {
+		{0, 0, 0, 0, 0, 0}, 0};
+	uint16_t cur_idx = res_base_idx;
+	uint64_t vb_addr = 0;
+	uint64_t vb_hdr_addr = 0;
+	uint32_t seg_offset = 0;
+	uint32_t vb_offset = 0;
+	uint32_t seg_avail;
+	uint32_t vb_avail;
+	uint32_t cpy_len, entry_len;
+
+	if (pkt == NULL)
+		return 0;
+
+	LOG_DEBUG(VHOST_DATA, "(%"PRIu64") Current Index %d| "
+		"End Index %d\n",
+		dev->device_fh, cur_idx, res_end_idx);
+
+	/*
+	 * Convert from gpa to vva
+	 * (guest physical addr -> vhost virtual addr)
+	 */
+	vq = dev->virtqueue[VIRTIO_RXQ];
+	vb_addr =
+		gpa_to_vva(dev, vq->buf_vec[vec_idx].buf_addr);
+	vb_hdr_addr = vb_addr;
+
+	/* Prefetch buffer address. */
+	rte_prefetch0((void *)(uintptr_t)vb_addr);
+
+	virtio_hdr.num_buffers = res_end_idx - res_base_idx;
+
+	LOG_DEBUG(VHOST_DATA, "(%"PRIu64") RX: Num merge buffers %d\n",
+		dev->device_fh, virtio_hdr.num_buffers);
+
+	rte_memcpy((void *)(uintptr_t)vb_hdr_addr,
+		(const void *)&virtio_hdr, vq->vhost_hlen);
+
+	VHOST_PRINT_PACKET(dev, (uintptr_t)vb_hdr_addr, vq->vhost_hlen, 1);
+
+	seg_avail = rte_pktmbuf_data_len(pkt);
+	vb_offset = vq->vhost_hlen;
+	vb_avail =
+		vq->buf_vec[vec_idx].buf_len - vq->vhost_hlen;
+
+	entry_len = vq->vhost_hlen;
+
+	if (vb_avail == 0) {
+		uint32_t desc_idx =
+			vq->buf_vec[vec_idx].desc_idx;
+		vq->desc[desc_idx].len = vq->vhost_hlen;
+
+		if ((vq->desc[desc_idx].flags
+			& VRING_DESC_F_NEXT) == 0) {
+			/* Update used ring with desc information */
+			vq->used->ring[cur_idx & (vq->size - 1)].id
+				= vq->buf_vec[vec_idx].desc_idx;
+			vq->used->ring[cur_idx & (vq->size - 1)].len
+				= entry_len;
+
+			entry_len = 0;
+			cur_idx++;
+			entry_success++;
+		}
+
+		vec_idx++;
+		vb_addr =
+			gpa_to_vva(dev, vq->buf_vec[vec_idx].buf_addr);
+
+		/* Prefetch buffer address. */
+		rte_prefetch0((void *)(uintptr_t)vb_addr);
+		vb_offset = 0;
+		vb_avail = vq->buf_vec[vec_idx].buf_len;
+	}
+
+	cpy_len = RTE_MIN(vb_avail, seg_avail);
+
+	while (cpy_len > 0) {
+		/* Copy mbuf data to vring buffer */
+		rte_memcpy((void *)(uintptr_t)(vb_addr + vb_offset),
+			(const void *)(rte_pktmbuf_mtod(pkt, char*) + seg_offset),
+			cpy_len);
+
+		VHOST_PRINT_PACKET(dev,
+			(uintptr_t)(vb_addr + vb_offset),
+			cpy_len, 0);
+
+		seg_offset += cpy_len;
+		vb_offset += cpy_len;
+		seg_avail -= cpy_len;
+		vb_avail -= cpy_len;
+		entry_len += cpy_len;
+
+		if (seg_avail != 0) {
+			/*
+			 * The virtio buffer in this vring
+			 * entry reach to its end.
+			 * But the segment doesn't complete.
+			 */
+			if ((vq->desc[vq->buf_vec[vec_idx].desc_idx].flags &
+				VRING_DESC_F_NEXT) == 0) {
+				/* Update used ring with desc information */
+				vq->used->ring[cur_idx & (vq->size - 1)].id
+					= vq->buf_vec[vec_idx].desc_idx;
+				vq->used->ring[cur_idx & (vq->size - 1)].len
+					= entry_len;
+				entry_len = 0;
+				cur_idx++;
+				entry_success++;
+			}
+
+			vec_idx++;
+			vb_addr = gpa_to_vva(dev,
+				vq->buf_vec[vec_idx].buf_addr);
+			vb_offset = 0;
+			vb_avail = vq->buf_vec[vec_idx].buf_len;
+			cpy_len = RTE_MIN(vb_avail, seg_avail);
+		} else {
+			/*
+			 * This current segment complete, need continue to
+			 * check if the whole packet complete or not.
+			 */
+			pkt = pkt->pkt.next;
+			if (pkt != NULL) {
+				/*
+				 * There are more segments.
+				 */
+				if (vb_avail == 0) {
+					/*
+					 * This current buffer from vring is
+					 * used up, need fetch next buffer
+					 * from buf_vec.
+					 */
+					uint32_t desc_idx =
+						vq->buf_vec[vec_idx].desc_idx;
+					vq->desc[desc_idx].len = vb_offset;
+
+					if ((vq->desc[desc_idx].flags &
+						VRING_DESC_F_NEXT) == 0) {
+						uint16_t wrapped_idx =
+							cur_idx & (vq->size - 1);
+						/*
+						 * Update used ring with the
+						 * descriptor information
+						 */
+						vq->used->ring[wrapped_idx].id
+							= desc_idx;
+						vq->used->ring[wrapped_idx].len
+							= entry_len;
+						entry_success++;
+						entry_len = 0;
+						cur_idx++;
+					}
+
+					/* Get next buffer from buf_vec. */
+					vec_idx++;
+					vb_addr = gpa_to_vva(dev,
+						vq->buf_vec[vec_idx].buf_addr);
+					vb_avail =
+						vq->buf_vec[vec_idx].buf_len;
+					vb_offset = 0;
+				}
+
+				seg_offset = 0;
+				seg_avail = rte_pktmbuf_data_len(pkt);
+				cpy_len = RTE_MIN(vb_avail, seg_avail);
+			} else {
+				/*
+				 * This whole packet completes.
+				 */
+				uint32_t desc_idx =
+					vq->buf_vec[vec_idx].desc_idx;
+				vq->desc[desc_idx].len = vb_offset;
+
+				while (vq->desc[desc_idx].flags &
+					VRING_DESC_F_NEXT) {
+					desc_idx = vq->desc[desc_idx].next;
+					 vq->desc[desc_idx].len = 0;
+				}
+
+				/* Update used ring with desc information */
+				vq->used->ring[cur_idx & (vq->size - 1)].id
+					= vq->buf_vec[vec_idx].desc_idx;
+				vq->used->ring[cur_idx & (vq->size - 1)].len
+					= entry_len;
+				entry_len = 0;
+				cur_idx++;
+				entry_success++;
+				seg_avail = 0;
+				cpy_len = RTE_MIN(vb_avail, seg_avail);
+			}
+		}
+	}
+
+	return entry_success;
+}
+
+/*
+ * This function works for mergeable RX.
+ */
+static inline uint32_t __attribute__((always_inline))
+virtio_dev_merge_rx(struct virtio_net *dev, uint16_t queue_id, struct rte_mbuf **pkts,
+	uint32_t count)
+{
+	struct vhost_virtqueue *vq;
+	uint32_t pkt_idx = 0, entry_success = 0;
+	uint16_t avail_idx, res_cur_idx;
+	uint16_t res_base_idx, res_end_idx;
+	uint8_t success = 0;
+
+	LOG_DEBUG(VHOST_DATA, "(%"PRIu64") virtio_dev_merge_rx()\n",
+		dev->device_fh);
+	if (unlikely(queue_id != VIRTIO_RXQ)) {
+		LOG_DEBUG(VHOST_DATA, "mq isn't supported in this version.\n");
+	}
+
+	vq = dev->virtqueue[VIRTIO_RXQ];
+	count = RTE_MIN((uint32_t)VHOST_MAX_PKT_BURST, count);
+
+	if (count == 0)
+		return 0;
+
+	for (pkt_idx = 0; pkt_idx < count; pkt_idx++) {
+		uint32_t secure_len = 0;
+		uint16_t need_cnt;
+		uint32_t vec_idx = 0;
+		uint32_t pkt_len = pkts[pkt_idx]->pkt.pkt_len + vq->vhost_hlen;
+		uint16_t i, id;
+
+		do {
+			/*
+			 * As many data cores may want access to available
+			 * buffers, they need to be reserved.
+			 */
+			res_base_idx = vq->last_used_idx_res;
+			res_cur_idx = res_base_idx;
+
+			do {
+				avail_idx = *((volatile uint16_t *)&vq->avail->idx);
+				if (unlikely(res_cur_idx == avail_idx)) {
+					LOG_DEBUG(VHOST_DATA,
+						"(%"PRIu64") Failed "
+						"to get enough desc from "
+						"vring\n",
+						dev->device_fh);
+					return pkt_idx;
+				} else {
+					uint16_t wrapped_idx =
+						(res_cur_idx) & (vq->size - 1);
+					uint32_t idx =
+						vq->avail->ring[wrapped_idx];
+					uint8_t next_desc;
+
+					do {
+						next_desc = 0;
+						secure_len += vq->desc[idx].len;
+						if (vq->desc[idx].flags &
+							VRING_DESC_F_NEXT) {
+							idx = vq->desc[idx].next;
+							next_desc = 1;
+						}
+					} while (next_desc);
+
+					res_cur_idx++;
+				}
+			} while (pkt_len > secure_len);
+
+			/* vq->last_used_idx_res is atomically updated. */
+			success = rte_atomic16_cmpset(&vq->last_used_idx_res,
+							res_base_idx,
+							res_cur_idx);
+		} while (success == 0);
+
+		id = res_base_idx;
+		need_cnt = res_cur_idx - res_base_idx;
+
+		for (i = 0; i < need_cnt; i++, id++) {
+			uint16_t wrapped_idx = id & (vq->size - 1);
+			uint32_t idx = vq->avail->ring[wrapped_idx];
+			uint8_t next_desc;
+			do {
+				next_desc = 0;
+				vq->buf_vec[vec_idx].buf_addr =
+					vq->desc[idx].addr;
+				vq->buf_vec[vec_idx].buf_len =
+					vq->desc[idx].len;
+				vq->buf_vec[vec_idx].desc_idx = idx;
+				vec_idx++;
+
+				if (vq->desc[idx].flags & VRING_DESC_F_NEXT) {
+					idx = vq->desc[idx].next;
+					next_desc = 1;
+				}
+			} while (next_desc);
+		}
+
+		res_end_idx = res_cur_idx;
+
+		entry_success = copy_from_mbuf_to_vring(dev, res_base_idx,
+			res_end_idx, pkts[pkt_idx]);
+
+		rte_compiler_barrier();
+
+		/*
+		 * Wait until it's our turn to add our buffer
+		 * to the used ring.
+		 */
+		while (unlikely(vq->last_used_idx != res_base_idx))
+			rte_pause();
+
+		*(volatile uint16_t *)&vq->used->idx += entry_success;
+		vq->last_used_idx = res_end_idx;
+
+		/* Kick the guest if necessary. */
+		if (!(vq->avail->flags & VRING_AVAIL_F_NO_INTERRUPT))
+			eventfd_write((int)vq->kickfd, 1);
+	}
+
+	return count;
+}
+
+uint32_t
+rte_vhost_enqueue_burst(struct virtio_net *dev, uint16_t queue_id, struct rte_mbuf **pkts, uint32_t count)
+{
+	if (unlikely(dev->features & (1 << VIRTIO_NET_F_MRG_RXBUF)))
+		return virtio_dev_merge_rx(dev, queue_id, pkts, count);
+	else
+		return virtio_dev_rx(dev, queue_id, pkts, count);
+}
+
+
 
 uint32_t
 rte_vhost_dequeue_burst(struct virtio_net *dev, uint16_t queue_id, struct rte_mempool *mbuf_pool, struct rte_mbuf **pkts, uint32_t count)
 {
-	struct rte_mbuf *mbuf;
+	struct rte_mbuf *m, *prev;
 	struct vhost_virtqueue *vq;
 	struct vring_desc *desc;
-	uint64_t buff_addr = 0;
+	uint64_t vb_addr = 0;
 	uint32_t head[VHOST_MAX_PKT_BURST];
 	uint32_t used_idx;
 	uint32_t i;
-	uint16_t free_entries, packet_success = 0;
+	uint16_t free_entries, entry_success = 0;
 	uint16_t avail_idx;
 
 	if (unlikely(queue_id != VIRTIO_TXQ)) {
@@ -223,7 +542,8 @@ rte_vhost_dequeue_burst(struct virtio_net *dev, uint16_t queue_id, struct rte_me
 	if (vq->last_used_idx == avail_idx)
 		return 0;
 
-	LOG_DEBUG(VHOST_DATA, "(%"PRIu64") virtio_dev_tx()\n", dev->device_fh);
+	LOG_DEBUG(VHOST_DATA, "(%"PRIu64") %s()\n", __func__,
+		dev->device_fh);
 
 	/* Prefetch available ring to retrieve head indexes. */
 	rte_prefetch0(&vq->avail->ring[vq->last_used_idx & (vq->size - 1)]);
@@ -231,11 +551,9 @@ rte_vhost_dequeue_burst(struct virtio_net *dev, uint16_t queue_id, struct rte_me
 	/*get the number of free entries in the ring*/
 	free_entries = (avail_idx - vq->last_used_idx);
 
-	if (free_entries > count)
-		free_entries = count;
+	free_entries = RTE_MIN(free_entries, count);
 	/* Limit to MAX_PKT_BURST. */
-	if (free_entries > VHOST_MAX_PKT_BURST)
-		free_entries = VHOST_MAX_PKT_BURST;
+	free_entries = RTE_MIN(free_entries, VHOST_MAX_PKT_BURST);
 
 	LOG_DEBUG(VHOST_DATA, "(%"PRIu64") Buffers available %d\n", dev->device_fh, free_entries);
 	/* Retrieve all of the head indexes first to avoid caching issues. */
@@ -243,56 +561,166 @@ rte_vhost_dequeue_burst(struct virtio_net *dev, uint16_t queue_id, struct rte_me
 		head[i] = vq->avail->ring[(vq->last_used_idx + i) & (vq->size - 1)];
 
 	/* Prefetch descriptor index. */
-	rte_prefetch0(&vq->desc[head[packet_success]]);
+	rte_prefetch0(&vq->desc[head[entry_success]]);
 	rte_prefetch0(&vq->used->ring[vq->last_used_idx & (vq->size - 1)]);
 
-	while (packet_success < free_entries) {
-		desc = &vq->desc[head[packet_success]];
+	while (entry_success < free_entries) {
+		uint32_t vb_avail, vb_offset;
+		uint32_t seg_avail, seg_offset;
+		uint32_t cpy_len;
+		uint32_t seg_num = 0;
+		struct rte_mbuf *cur;
+		uint8_t alloc_err = 0;
+
+		desc = &vq->desc[head[entry_success]];
 
 		/* Discard first buffer as it is the virtio header */
 		desc = &vq->desc[desc->next];
 
 		/* Buffer address translation. */
-		buff_addr = gpa_to_vva(dev, desc->addr);
+		vb_addr = gpa_to_vva(dev, desc->addr);
 		/* Prefetch buffer address. */
-		rte_prefetch0((void*)(uintptr_t)buff_addr);
+		rte_prefetch0((void *)(uintptr_t)vb_addr);
 
 		used_idx = vq->last_used_idx & (vq->size - 1);
 
-		if (packet_success < (free_entries - 1)) {
+		if (entry_success < (free_entries - 1)) {
 			/* Prefetch descriptor index. */
-			rte_prefetch0(&vq->desc[head[packet_success+1]]);
+			rte_prefetch0(&vq->desc[head[entry_success+1]]);
 			rte_prefetch0(&vq->used->ring[(used_idx + 1) & (vq->size - 1)]);
 		}
 
 		/* Update used index buffer information. */
-		vq->used->ring[used_idx].id = head[packet_success];
+		vq->used->ring[used_idx].id = head[entry_success];
 		vq->used->ring[used_idx].len = 0;
 
-		mbuf = rte_pktmbuf_alloc(mbuf_pool);
-		if (unlikely(mbuf == NULL)) {
-			RTE_LOG(ERR, VHOST_DATA, "Failed to allocate memory for mbuf.\n");
-			return packet_success;
+		vb_offset = 0;
+		vb_avail = desc->len;
+		
+		seg_avail = 0;
+		/* Allocate an mbuf and populate the structure. */
+		m = rte_pktmbuf_alloc(mbuf_pool);
+		if (unlikely(m == NULL)) {
+			RTE_LOG(ERR, VHOST_DATA,
+				"Failed to allocate memory for mbuf.\n");
+			return entry_success;
 		}
-		mbuf->pkt.data_len = desc->len;
-		mbuf->pkt.pkt_len  = mbuf->pkt.data_len;
+		seg_offset = 0;
+		seg_avail = m->buf_len - RTE_PKTMBUF_HEADROOM;
+		cpy_len = RTE_MIN(vb_avail, seg_avail);
+
+		VHOST_PRINT_PACKET(dev, (uintptr_t)vb_addr, desc->len, 0);
+
+		
+		seg_num++;
+		cur = m;
+		prev = m;
+		while (cpy_len != 0) {
+			rte_memcpy((void *)(rte_pktmbuf_mtod(cur, char *) + seg_offset),
+				(void *)((uintptr_t)(vb_addr + vb_offset)),
+				cpy_len);
+
+			seg_offset += cpy_len;
+			vb_offset += cpy_len;
+			vb_avail -= cpy_len;
+			seg_avail -= cpy_len;
+
+			if (vb_avail != 0) {
+				/*
+				 * The segment reachs to its end,
+				 * while the virtio buffer in TX vring has
+				 * more data to be copied.
+				 */
+				cur->pkt.data_len = seg_offset;
+				m->pkt.pkt_len += seg_offset;
+				/* Allocate mbuf and populate the structure. */
+				cur = rte_pktmbuf_alloc(mbuf_pool);
+				if (unlikely(cur == NULL)) {
+					RTE_LOG(ERR, VHOST_DATA, "Failed to "
+						"allocate memory for mbuf.\n");
+					rte_pktmbuf_free(m);
+					alloc_err = 1;
+					break;
+				}
+
+				seg_num++;
+				prev->pkt.next = cur;
+				prev = cur;
+				seg_offset = 0;
+				seg_avail = cur->buf_len - RTE_PKTMBUF_HEADROOM;
+			} else {
+				if (desc->flags & VRING_DESC_F_NEXT) {
+					/*
+					 * There are more virtio buffers in
+					 * same vring entry need to be copied.
+					 */
+					if (seg_avail == 0) {
+						/*
+						 * The current segment hasn't
+						 * room to accomodate more
+						 * data.
+						 */
+						cur->pkt.data_len = seg_offset;
+						m->pkt.pkt_len += seg_offset;
+						/*
+						 * Allocate an mbuf and
+						 * populate the structure.
+						 */
+						cur = rte_pktmbuf_alloc(mbuf_pool);
+						if (unlikely(cur == NULL)) {
+							RTE_LOG(ERR,
+								VHOST_DATA,
+								"Failed to "
+								"allocate memory "
+								"for mbuf\n");
+							rte_pktmbuf_free(m);
+							alloc_err = 1;
+							break;
+						}
+						seg_num++;
+						prev->pkt.next = cur;
+						prev = cur;
+						seg_offset = 0;
+						seg_avail = cur->buf_len - RTE_PKTMBUF_HEADROOM;
+					}
+
+					desc = &vq->desc[desc->next];
+
+					/* Buffer address translation. */
+					vb_addr = gpa_to_vva(dev, desc->addr);
+					/* Prefetch buffer address. */
+					rte_prefetch0((void *)(uintptr_t)vb_addr);
+					vb_offset = 0;
+					vb_avail = desc->len;
+
+					VHOST_PRINT_PACKET(dev, (uintptr_t)vb_addr,
+						desc->len, 0);
+				} else {
+					/* The whole packet completes. */
+					cur->pkt.data_len = seg_offset;
+					m->pkt.pkt_len += seg_offset;
+					vb_avail = 0;
+				}
+			}
 
-		rte_memcpy((void *) mbuf->pkt.data,
-			(const void *) buff_addr, mbuf->pkt.data_len);
+			cpy_len = RTE_MIN(vb_avail, seg_avail);
+		}
 
-		pkts[packet_success] = mbuf;
+		if (unlikely(alloc_err == 1))
+			break;
 
-		VHOST_PRINT_PACKET(dev, (uintptr_t)buff_addr, desc->len, 0);
+		m->pkt.nb_segs = seg_num;
 
+		pkts[entry_success] = m;
 		vq->last_used_idx++;
-		packet_success++;
+		entry_success++;
 	}
 
 	rte_compiler_barrier();
-	vq->used->idx += packet_success;
+	vq->used->idx += entry_success;
 	/* Kick guest if required. */
 	if (!(vq->avail->flags & VRING_AVAIL_F_NO_INTERRUPT))
 		eventfd_write((int)vq->kickfd, 1);
+	return entry_success;
 
-	return packet_success;
 }
-- 
1.8.1.4

^ permalink raw reply	[flat|nested] 23+ messages in thread

* [dpdk-dev] [PATCH v5 05/11] lib/librte_vhost: merge Oliver's mbuf change
  2014-09-26  9:45 [dpdk-dev] [PATCH v5 00/11] user space vhost library and vhost example Huawei Xie
                   ` (3 preceding siblings ...)
  2014-09-26  9:45 ` [dpdk-dev] [PATCH v5 04/11] lib/librte_vhost: merge vhost merge-able rx. merge vhost tx fix Huawei Xie
@ 2014-09-26  9:45 ` Huawei Xie
  2014-09-29 19:44   ` Thomas Monjalon
  2014-09-26  9:45 ` [dpdk-dev] [PATCH v5 06/11] lib/librte_vhost: fixes serious coding style issues Huawei Xie
                   ` (5 subsequent siblings)
  10 siblings, 1 reply; 23+ messages in thread
From: Huawei Xie @ 2014-09-26  9:45 UTC (permalink / raw)
  To: dev

There is no rte_pktmbuf structure in mbuf now. Its fields are merged to
rte_mbuf structure.

Signed-off-by: Huawei Xie <huawei.xie@intel.com>
---
 lib/librte_vhost/vhost_rxtx.c | 24 ++++++++++++------------
 1 file changed, 12 insertions(+), 12 deletions(-)

diff --git a/lib/librte_vhost/vhost_rxtx.c b/lib/librte_vhost/vhost_rxtx.c
index 81368e6..688e661 100644
--- a/lib/librte_vhost/vhost_rxtx.c
+++ b/lib/librte_vhost/vhost_rxtx.c
@@ -145,7 +145,7 @@ virtio_dev_rx(struct virtio_net *dev, uint16_t queue_id, struct rte_mbuf **pkts,
 		/* Copy mbuf data to buffer */
 		/* TODO fixme for sg mbuf and the case that desc couldn't hold the mbuf data */
 		rte_memcpy((void *)(uintptr_t)buff_addr,
-			(const void *)buff->pkt.data,
+			rte_pktmbuf_mtod(buff, const void *),
 			rte_pktmbuf_data_len(buff));
 		VHOST_PRINT_PACKET(dev, (uintptr_t)buff_addr,
 			rte_pktmbuf_data_len(buff), 0);
@@ -307,7 +307,7 @@ copy_from_mbuf_to_vring(struct virtio_net *dev, uint16_t res_base_idx,
 			 * This current segment complete, need continue to
 			 * check if the whole packet complete or not.
 			 */
-			pkt = pkt->pkt.next;
+			pkt = pkt->next;
 			if (pkt != NULL) {
 				/*
 				 * There are more segments.
@@ -411,7 +411,7 @@ virtio_dev_merge_rx(struct virtio_net *dev, uint16_t queue_id, struct rte_mbuf *
 		uint32_t secure_len = 0;
 		uint16_t need_cnt;
 		uint32_t vec_idx = 0;
-		uint32_t pkt_len = pkts[pkt_idx]->pkt.pkt_len + vq->vhost_hlen;
+		uint32_t pkt_len = pkts[pkt_idx]->pkt_len + vq->vhost_hlen;
 		uint16_t i, id;
 
 		do {
@@ -631,8 +631,8 @@ rte_vhost_dequeue_burst(struct virtio_net *dev, uint16_t queue_id, struct rte_me
 				 * while the virtio buffer in TX vring has
 				 * more data to be copied.
 				 */
-				cur->pkt.data_len = seg_offset;
-				m->pkt.pkt_len += seg_offset;
+				cur->data_len = seg_offset;
+				m->pkt_len += seg_offset;
 				/* Allocate mbuf and populate the structure. */
 				cur = rte_pktmbuf_alloc(mbuf_pool);
 				if (unlikely(cur == NULL)) {
@@ -644,7 +644,7 @@ rte_vhost_dequeue_burst(struct virtio_net *dev, uint16_t queue_id, struct rte_me
 				}
 
 				seg_num++;
-				prev->pkt.next = cur;
+				prev->next = cur;
 				prev = cur;
 				seg_offset = 0;
 				seg_avail = cur->buf_len - RTE_PKTMBUF_HEADROOM;
@@ -660,8 +660,8 @@ rte_vhost_dequeue_burst(struct virtio_net *dev, uint16_t queue_id, struct rte_me
 						 * room to accomodate more
 						 * data.
 						 */
-						cur->pkt.data_len = seg_offset;
-						m->pkt.pkt_len += seg_offset;
+						cur->data_len = seg_offset;
+						m->pkt_len += seg_offset;
 						/*
 						 * Allocate an mbuf and
 						 * populate the structure.
@@ -678,7 +678,7 @@ rte_vhost_dequeue_burst(struct virtio_net *dev, uint16_t queue_id, struct rte_me
 							break;
 						}
 						seg_num++;
-						prev->pkt.next = cur;
+						prev->next = cur;
 						prev = cur;
 						seg_offset = 0;
 						seg_avail = cur->buf_len - RTE_PKTMBUF_HEADROOM;
@@ -697,8 +697,8 @@ rte_vhost_dequeue_burst(struct virtio_net *dev, uint16_t queue_id, struct rte_me
 						desc->len, 0);
 				} else {
 					/* The whole packet completes. */
-					cur->pkt.data_len = seg_offset;
-					m->pkt.pkt_len += seg_offset;
+					cur->data_len = seg_offset;
+					m->pkt_len += seg_offset;
 					vb_avail = 0;
 				}
 			}
@@ -709,7 +709,7 @@ rte_vhost_dequeue_burst(struct virtio_net *dev, uint16_t queue_id, struct rte_me
 		if (unlikely(alloc_err == 1))
 			break;
 
-		m->pkt.nb_segs = seg_num;
+		m->nb_segs = seg_num;
 
 		pkts[entry_success] = m;
 		vq->last_used_idx++;
-- 
1.8.1.4

^ permalink raw reply	[flat|nested] 23+ messages in thread

* [dpdk-dev] [PATCH v5 06/11] lib/librte_vhost: fixes serious coding style issues
  2014-09-26  9:45 [dpdk-dev] [PATCH v5 00/11] user space vhost library and vhost example Huawei Xie
                   ` (4 preceding siblings ...)
  2014-09-26  9:45 ` [dpdk-dev] [PATCH v5 05/11] lib/librte_vhost: merge Oliver's mbuf change Huawei Xie
@ 2014-09-26  9:45 ` Huawei Xie
  2014-09-26  9:45 ` [dpdk-dev] [PATCH v5 07/11] lib/librte_vhost: add vhost support in DPDK makefile Huawei Xie
                   ` (4 subsequent siblings)
  10 siblings, 0 replies; 23+ messages in thread
From: Huawei Xie @ 2014-09-26  9:45 UTC (permalink / raw)
  To: dev

fixes checkpatch reported issues.

Signed-off-by: Huawei Xie <huawei.xie@intel.com>
---
 lib/librte_vhost/rte_virtio_net.h |  55 +++++----
 lib/librte_vhost/vhost-net-cdev.c | 236 +++++++++++++++++++-------------------
 lib/librte_vhost/vhost-net-cdev.h |  33 +++---
 lib/librte_vhost/vhost_rxtx.c     |  57 +++++----
 lib/librte_vhost/virtio-net.c     | 149 ++++++++++++++----------
 5 files changed, 281 insertions(+), 249 deletions(-)

diff --git a/lib/librte_vhost/rte_virtio_net.h b/lib/librte_vhost/rte_virtio_net.h
index 99ddfc1..06cbdf7 100644
--- a/lib/librte_vhost/rte_virtio_net.h
+++ b/lib/librte_vhost/rte_virtio_net.h
@@ -66,19 +66,18 @@ struct buf_vector {
 /**
  * Structure contains variables relevant to RX/TX virtqueues.
  */
-struct vhost_virtqueue
-{
-	struct vring_desc	*desc;				/* Virtqueue descriptor ring. */
-	struct vring_avail	*avail;				/* Virtqueue available ring. */
-	struct vring_used	*used;				/* Virtqueue used ring. */
-	uint32_t			size;				/* Size of descriptor ring. */
-	uint32_t			backend;			/* Backend value to determine if device should started/stopped. */
-	uint16_t			vhost_hlen;			/* Vhost header length (varies depending on RX merge buffers. */
+struct vhost_virtqueue {
+	struct vring_desc	*desc;			/* Virtqueue descriptor ring. */
+	struct vring_avail	*avail;			/* Virtqueue available ring. */
+	struct vring_used	*used;			/* Virtqueue used ring. */
+	uint32_t		size;			/* Size of descriptor ring. */
+	uint32_t		backend;		/* Backend value to determine if device should started/stopped. */
+	uint16_t		vhost_hlen;		/* Vhost header length (varies depending on RX merge buffers. */
 	volatile uint16_t	last_used_idx;		/* Last index used on the available ring */
 	volatile uint16_t	last_used_idx_res;	/* Used for multiple devices reserving buffers. */
-	eventfd_t			callfd;				/* Currently unused as polling mode is enabled. */
-	eventfd_t			kickfd;				/* Used to notify the guest (trigger interrupt). */
-	struct buf_vector    buf_vec[BUF_VECTOR_MAX]; /**< for scatter RX. */
+	eventfd_t		callfd;			/* Currently unused as polling mode is enabled. */
+	eventfd_t		kickfd;			/* Used to notify the guest (trigger interrupt). */
+	struct buf_vector	buf_vec[BUF_VECTOR_MAX]; /**< for scatter RX. */
 } __rte_cache_aligned;
 
 
@@ -86,11 +85,11 @@ struct vhost_virtqueue
  * Information relating to memory regions including offsets to addresses in QEMUs memory file.
  */
 struct virtio_memory_regions {
-	uint64_t	guest_phys_address;		/* Base guest physical address of region. */
+	uint64_t	guest_phys_address;	/* Base guest physical address of region. */
 	uint64_t	guest_phys_address_end;	/* End guest physical address of region. */
-	uint64_t	memory_size;			/* Size of region. */
-	uint64_t	userspace_address;		/* Base userspace address of region. */
-	uint64_t	address_offset;			/* Offset of region for address translation. */
+	uint64_t	memory_size;		/* Size of region. */
+	uint64_t	userspace_address;	/* Base userspace address of region. */
+	uint64_t	address_offset;		/* Offset of region for address translation. */
 };
 
 
@@ -98,31 +97,31 @@ struct virtio_memory_regions {
  * Memory structure includes region and mapping information.
  */
 struct virtio_memory {
-	uint64_t    base_address;    /**< Base QEMU userspace address of the memory file. */
-	uint64_t    mapped_address;  /**< Mapped address of memory file base in our applications memory space. */
-	uint64_t    mapped_size;     /**< Total size of memory file. */
-	uint32_t    nregions;        /**< Number of memory regions. */
-	struct virtio_memory_regions      regions[0]; /**< Memory region information. */
+	uint64_t	base_address;	/**< Base QEMU userspace address of the memory file. */
+	uint64_t	mapped_address;	/**< Mapped address of memory file base in our applications memory space. */
+	uint64_t	mapped_size;	/**< Total size of memory file. */
+	uint32_t	nregions;	/**< Number of memory regions. */
+	struct		virtio_memory_regions      regions[0];	/**< Memory region information. */
 };
 
 /**
  * Device structure contains all configuration information relating to the device.
  */
 struct virtio_net {
-	struct vhost_virtqueue  *virtqueue[VIRTIO_QNUM]; /**< Contains all virtqueue information. */
-	struct virtio_memory    *mem;                    /**< QEMU memory and memory region information. */
-	uint64_t features;    /**< Negotiated feature set. */
-	uint64_t device_fh;   /**< Device identifier. */
-	uint32_t flags;       /**< Device flags. Only used to check if device is running on data core. */
-	void     *priv;
+	struct vhost_virtqueue	*virtqueue[VIRTIO_QNUM];	/**< Contains all virtqueue information. */
+	struct virtio_memory	*mem;				/**< QEMU memory and memory region information. */
+	uint64_t features;	/**< Negotiated feature set. */
+	uint64_t device_fh;	/**< Device identifier. */
+	uint32_t flags;		/**< Device flags. Only used to check if device is running on data core. */
+	void     *priv;		/**< User context. */
 } __rte_cache_aligned;
 
 /**
  * Device operations to add/remove device.
  */
 struct virtio_net_device_ops {
-	int (*new_device)(struct virtio_net *); /**< Add device. */
-	void (*destroy_device)(struct virtio_net *); /**< Remove device. */
+	int (*new_device)(struct virtio_net *);		/**< Add device. */
+	void (*destroy_device)(struct virtio_net *);	/**< Remove device. */
 };
 
 
diff --git a/lib/librte_vhost/vhost-net-cdev.c b/lib/librte_vhost/vhost-net-cdev.c
index e73bf23..499e9b3 100644
--- a/lib/librte_vhost/vhost-net-cdev.c
+++ b/lib/librte_vhost/vhost-net-cdev.c
@@ -46,9 +46,9 @@
 
 #include "vhost-net-cdev.h"
 
-#define FUSE_OPT_DUMMY 		"\0\0"
-#define FUSE_OPT_FORE 		"-f\0\0"
-#define FUSE_OPT_NOMULTI 	"-s\0\0"
+#define FUSE_OPT_DUMMY		"\0\0"
+#define FUSE_OPT_FORE		"-f\0\0"
+#define FUSE_OPT_NOMULTI	"-s\0\0"
 
 static const uint32_t	default_major = 231;
 static const uint32_t	default_minor = 1;
@@ -113,61 +113,61 @@ vhost_net_release(fuse_req_t req, struct fuse_file_info *fi)
  * Boilerplate code for CUSE IOCTL
  * Implicit arguments: ctx, req, result.
  */
-#define VHOST_IOCTL(func) do {								\
-	result = (func)(ctx);									\
-	fuse_reply_ioctl(req, result, NULL, 0);					\
-} while(0)													
+#define VHOST_IOCTL(func) do {			\
+	result = (func)(ctx);			\
+	fuse_reply_ioctl(req, result, NULL, 0);	\
+} while (0)
 
 /*
  * Boilerplate IOCTL RETRY
  * Implicit arguments: req.
  */
-#define VHOST_IOCTL_RETRY(size_r, size_w) do {									\
-	struct iovec iov_r = { arg, (size_r) };										\
-	struct iovec iov_w = { arg, (size_w) };										\
+#define VHOST_IOCTL_RETRY(size_r, size_w) do {		\
+	struct iovec iov_r = { arg, (size_r) };		\
+	struct iovec iov_w = { arg, (size_w) };		\
 	fuse_reply_ioctl_retry(req, &iov_r, (size_r)?1:0, &iov_w, (size_w)?1:0);	\
-} while(0)																		\
+} while (0)
 
 /*
  * Boilerplate code for CUSE Read IOCTL
  * Implicit arguments: ctx, req, result, in_bufsz, in_buf.
  */
-#define VHOST_IOCTL_R(type, var, func) do {				\
-	if (!in_bufsz) {									\
-		VHOST_IOCTL_RETRY(sizeof(type), 0);				\
-	} else {											\
-		(var) = *(const type * ) in_buf;				\
-		result = func(ctx, &(var));						\
-		fuse_reply_ioctl(req, result, NULL, 0);			\
-	}													\
-} while(0)												\
+#define VHOST_IOCTL_R(type, var, func) do {		\
+	if (!in_bufsz) {				\
+		VHOST_IOCTL_RETRY(sizeof(type), 0);	\
+	} else {					\
+		(var) = *(const type*) in_buf;	\
+		result = func(ctx, &(var));		\
+		fuse_reply_ioctl(req, result, NULL, 0);	\
+	}						\
+} while (0)
 
 /*
  *	Boilerplate code for CUSE Write IOCTL
  * Implicit arguments: ctx, req, result, out_bufsz.
  */
-#define	VHOST_IOCTL_W(type, var, func) do {						\
-	if (!out_bufsz) {											\
-		VHOST_IOCTL_RETRY(0, sizeof(type));						\
-	} else {													\
-		result = (func)(ctx, &(var));							\
+#define	VHOST_IOCTL_W(type, var, func) do {		\
+	if (!out_bufsz) {				\
+		VHOST_IOCTL_RETRY(0, sizeof(type));	\
+	} else {					\
+		result = (func)(ctx, &(var));		\
 		fuse_reply_ioctl(req, result, &(var), sizeof(type));	\
-	}															\
-} while(0)														\
+	}								\
+} while (0)
 
 /*
  * Boilerplate code for CUSE Read/Write IOCTL
  * Implicit arguments: ctx, req, result, in_bufsz, in_buf.
  */
-#define VHOST_IOCTL_RW(type1, var1, type2, var2, func) do {			\
-	if (!in_bufsz) {												\
-		VHOST_IOCTL_RETRY(sizeof(type1), sizeof(type2));			\
-	} else {														\
-		(var1) = *(const type1* ) (in_buf);							\
-		result = (func)(ctx, (var1), &(var2));						\
-		fuse_reply_ioctl(req, result, &(var2), sizeof(type2));		\
-	}																\
-} while(0)															\
+#define VHOST_IOCTL_RW(type1, var1, type2, var2, func) do {		\
+	if (!in_bufsz) {						\
+		VHOST_IOCTL_RETRY(sizeof(type1), sizeof(type2));	\
+	} else {							\
+		(var1) = *(const type1*) (in_buf);			\
+		result = (func)(ctx, (var1), &(var2));			\
+		fuse_reply_ioctl(req, result, &(var2), sizeof(type2));	\
+	}								\
+} while (0)
 
 /*
  * The IOCTLs are handled using CUSE/FUSE in userspace. Depending on
@@ -187,106 +187,104 @@ vhost_net_ioctl(fuse_req_t req, int cmd, void *arg,
 	uint32_t index;
 	int result = 0;
 
-	switch(cmd)
-	{
-		case VHOST_NET_SET_BACKEND:
-			LOG_DEBUG(VHOST_CONFIG, "(%"PRIu64") IOCTL: VHOST_NET_SET_BACKEND\n", ctx.fh);
-			VHOST_IOCTL_R(struct vhost_vring_file, file, ops->set_backend);
-			break;
+	switch (cmd) {
+	case VHOST_NET_SET_BACKEND:
+		LOG_DEBUG(VHOST_CONFIG, "(%"PRIu64") IOCTL: VHOST_NET_SET_BACKEND\n", ctx.fh);
+		VHOST_IOCTL_R(struct vhost_vring_file, file, ops->set_backend);
+		break;
 
-		case VHOST_GET_FEATURES:
-			LOG_DEBUG(VHOST_CONFIG, "(%"PRIu64") IOCTL: VHOST_GET_FEATURES\n", ctx.fh);
-			VHOST_IOCTL_W(uint64_t, features, ops->get_features);
-			break;
+	case VHOST_GET_FEATURES:
+		LOG_DEBUG(VHOST_CONFIG, "(%"PRIu64") IOCTL: VHOST_GET_FEATURES\n", ctx.fh);
+		VHOST_IOCTL_W(uint64_t, features, ops->get_features);
+		break;
 
-		case VHOST_SET_FEATURES:
-			LOG_DEBUG(VHOST_CONFIG, "(%"PRIu64") IOCTL: VHOST_SET_FEATURES\n", ctx.fh);
-			VHOST_IOCTL_R(uint64_t, features, ops->set_features);
+	case VHOST_SET_FEATURES:
+		LOG_DEBUG(VHOST_CONFIG, "(%"PRIu64") IOCTL: VHOST_SET_FEATURES\n", ctx.fh);
+		VHOST_IOCTL_R(uint64_t, features, ops->set_features);
 			break;
 
-		case VHOST_RESET_OWNER:
-			LOG_DEBUG(VHOST_CONFIG, "(%"PRIu64") IOCTL: VHOST_RESET_OWNER\n", ctx.fh);
-			VHOST_IOCTL(ops->reset_owner);
-			break;
+	case VHOST_RESET_OWNER:
+		LOG_DEBUG(VHOST_CONFIG, "(%"PRIu64") IOCTL: VHOST_RESET_OWNER\n", ctx.fh);
+		VHOST_IOCTL(ops->reset_owner);
+		break;
 
-		case VHOST_SET_OWNER:
-			LOG_DEBUG(VHOST_CONFIG, "(%"PRIu64") IOCTL: VHOST_SET_OWNER\n", ctx.fh);
-			VHOST_IOCTL(ops->set_owner);
-			break;
+	case VHOST_SET_OWNER:
+		LOG_DEBUG(VHOST_CONFIG, "(%"PRIu64") IOCTL: VHOST_SET_OWNER\n", ctx.fh);
+		VHOST_IOCTL(ops->set_owner);
+		break;
 
-		case VHOST_SET_MEM_TABLE:
-			/*TODO fix race condition.*/
-			LOG_DEBUG(VHOST_CONFIG, "(%"PRIu64") IOCTL: VHOST_SET_MEM_TABLE\n", ctx.fh);
-			static struct vhost_memory mem_temp;
-
-			switch(in_bufsz){
-				case 0:
-					VHOST_IOCTL_RETRY(sizeof(struct vhost_memory), 0);
-					break;
-
-				case sizeof(struct vhost_memory):
-					mem_temp = *(const struct vhost_memory *) in_buf;
-
-					if (mem_temp.nregions > 0) {
-						VHOST_IOCTL_RETRY(sizeof(struct vhost_memory) + (sizeof(struct vhost_memory_region) * mem_temp.nregions), 0);
-					} else {
-						result = -1;
-						fuse_reply_ioctl(req, result, NULL, 0);
-					}
-					break;
-
-				default:
-					result = ops->set_mem_table(ctx, in_buf, mem_temp.nregions);
-					if (result)
-						fuse_reply_err(req, EINVAL);
-					else
-						fuse_reply_ioctl(req, result, NULL, 0);
+	case VHOST_SET_MEM_TABLE:
+		/*TODO fix race condition.*/
+		LOG_DEBUG(VHOST_CONFIG, "(%"PRIu64") IOCTL: VHOST_SET_MEM_TABLE\n", ctx.fh);
+		static struct vhost_memory mem_temp;
 
-			}
-
-			break;
-
-		case VHOST_SET_VRING_NUM:
-			LOG_DEBUG(VHOST_CONFIG, "(%"PRIu64") IOCTL: VHOST_SET_VRING_NUM\n", ctx.fh);
-			VHOST_IOCTL_R(struct vhost_vring_state, state, ops->set_vring_num);
+		switch (in_bufsz) {
+		case 0:
+			VHOST_IOCTL_RETRY(sizeof(struct vhost_memory), 0);
 			break;
 
-		case VHOST_SET_VRING_BASE:
-			LOG_DEBUG(VHOST_CONFIG, "(%"PRIu64") IOCTL: VHOST_SET_VRING_BASE\n", ctx.fh);
-			VHOST_IOCTL_R(struct vhost_vring_state, state, ops->set_vring_base);
-			break;
+		case sizeof(struct vhost_memory):
+			mem_temp = *(const struct vhost_memory *) in_buf;
 
-		case VHOST_GET_VRING_BASE:
-			LOG_DEBUG(VHOST_CONFIG, "(%"PRIu64") IOCTL: VHOST_GET_VRING_BASE\n", ctx.fh);
-			VHOST_IOCTL_RW(uint32_t, index, struct vhost_vring_state, state, ops->get_vring_base);
-			break;
-
-		case VHOST_SET_VRING_ADDR:
-			LOG_DEBUG(VHOST_CONFIG, "(%"PRIu64") IOCTL: VHOST_SET_VRING_ADDR\n", ctx.fh);
-			VHOST_IOCTL_R(struct vhost_vring_addr, addr, ops->set_vring_addr);
-			break;
-
-		case VHOST_SET_VRING_KICK:
-			LOG_DEBUG(VHOST_CONFIG, "(%"PRIu64") IOCTL: VHOST_SET_VRING_KICK\n", ctx.fh);
-			VHOST_IOCTL_R(struct vhost_vring_file, file, ops->set_vring_kick);
-			break;
-
-		case VHOST_SET_VRING_CALL:
-			LOG_DEBUG(VHOST_CONFIG, "(%"PRIu64") IOCTL: VHOST_SET_VRING_CALL\n", ctx.fh);
-			VHOST_IOCTL_R(struct vhost_vring_file, file, ops->set_vring_call);
+			if (mem_temp.nregions > 0) {
+				VHOST_IOCTL_RETRY(sizeof(struct vhost_memory) + (sizeof(struct vhost_memory_region) * mem_temp.nregions), 0);
+			} else {
+				result = -1;
+				fuse_reply_ioctl(req, result, NULL, 0);
+			}
 			break;
 
 		default:
-			RTE_LOG(ERR, VHOST_CONFIG, "(%"PRIu64") IOCTL: DOESN NOT EXIST\n", ctx.fh);
-			result = -1;
-			fuse_reply_ioctl(req, result, NULL, 0);
+			result = ops->set_mem_table(ctx, in_buf, mem_temp.nregions);
+			if (result)
+				fuse_reply_err(req, EINVAL);
+			else
+				fuse_reply_ioctl(req, result, NULL, 0);
+
+		}
+
+		break;
+
+	case VHOST_SET_VRING_NUM:
+		LOG_DEBUG(VHOST_CONFIG, "(%"PRIu64") IOCTL: VHOST_SET_VRING_NUM\n", ctx.fh);
+		VHOST_IOCTL_R(struct vhost_vring_state, state, ops->set_vring_num);
+		break;
+
+	case VHOST_SET_VRING_BASE:
+		LOG_DEBUG(VHOST_CONFIG, "(%"PRIu64") IOCTL: VHOST_SET_VRING_BASE\n", ctx.fh);
+		VHOST_IOCTL_R(struct vhost_vring_state, state, ops->set_vring_base);
+		break;
+
+	case VHOST_GET_VRING_BASE:
+		LOG_DEBUG(VHOST_CONFIG, "(%"PRIu64") IOCTL: VHOST_GET_VRING_BASE\n", ctx.fh);
+		VHOST_IOCTL_RW(uint32_t, index, struct vhost_vring_state, state, ops->get_vring_base);
+		break;
+
+	case VHOST_SET_VRING_ADDR:
+		LOG_DEBUG(VHOST_CONFIG, "(%"PRIu64") IOCTL: VHOST_SET_VRING_ADDR\n", ctx.fh);
+		VHOST_IOCTL_R(struct vhost_vring_addr, addr, ops->set_vring_addr);
+		break;
+
+	case VHOST_SET_VRING_KICK:
+		LOG_DEBUG(VHOST_CONFIG, "(%"PRIu64") IOCTL: VHOST_SET_VRING_KICK\n", ctx.fh);
+		VHOST_IOCTL_R(struct vhost_vring_file, file, ops->set_vring_kick);
+		break;
+
+	case VHOST_SET_VRING_CALL:
+		LOG_DEBUG(VHOST_CONFIG, "(%"PRIu64") IOCTL: VHOST_SET_VRING_CALL\n", ctx.fh);
+		VHOST_IOCTL_R(struct vhost_vring_file, file, ops->set_vring_call);
+		break;
+
+	default:
+		RTE_LOG(ERR, VHOST_CONFIG, "(%"PRIu64") IOCTL: DOESN NOT EXIST\n", ctx.fh);
+		result = -1;
+		fuse_reply_ioctl(req, result, NULL, 0);
 	}
 
-	if (result < 0) {
+	if (result < 0)
 		LOG_DEBUG(VHOST_CONFIG, "(%"PRIu64") IOCTL: FAIL\n", ctx.fh);
-	} else {
+	else
 		LOG_DEBUG(VHOST_CONFIG, "(%"PRIu64") IOCTL: SUCCESS\n", ctx.fh);
-	}
 }
 
 /*
diff --git a/lib/librte_vhost/vhost-net-cdev.h b/lib/librte_vhost/vhost-net-cdev.h
index d9a5a9a..f685f2b 100644
--- a/lib/librte_vhost/vhost-net-cdev.h
+++ b/lib/librte_vhost/vhost-net-cdev.h
@@ -76,10 +76,9 @@
 /*
  * Structure used to identify device context.
  */
-struct vhost_device_ctx
-{
+struct vhost_device_ctx {
 	pid_t		pid;	/* PID of process calling the IOCTL. */
-	uint64_t 	fh;		/* Populated with fi->fh to track the device index. */
+	uint64_t	fh;	/* Populated with fi->fh to track the device index. */
 };
 
 /*
@@ -87,26 +86,26 @@ struct vhost_device_ctx
  * functions are called in CUSE context and are used to configure devices.
  */
 struct vhost_net_device_ops {
-	int (* new_device) 		(struct vhost_device_ctx);
-	void (* destroy_device) (struct vhost_device_ctx);
+	int (*new_device)(struct vhost_device_ctx);
+	void (*destroy_device)(struct vhost_device_ctx);
 
-	int (* get_features) 	(struct vhost_device_ctx, uint64_t *);
-	int (* set_features) 	(struct vhost_device_ctx, uint64_t *);
+	int (*get_features)(struct vhost_device_ctx, uint64_t *);
+	int (*set_features)(struct vhost_device_ctx, uint64_t *);
 
-	int (* set_mem_table) 	(struct vhost_device_ctx, const void *, uint32_t);
+	int (*set_mem_table)(struct vhost_device_ctx, const void *, uint32_t);
 
-	int (* set_vring_num) 	(struct vhost_device_ctx, struct vhost_vring_state *);
-	int (* set_vring_addr) 	(struct vhost_device_ctx, struct vhost_vring_addr *);
-	int (* set_vring_base) 	(struct vhost_device_ctx, struct vhost_vring_state *);
-	int (* get_vring_base) 	(struct vhost_device_ctx, uint32_t, struct vhost_vring_state *);
+	int (*set_vring_num)(struct vhost_device_ctx, struct vhost_vring_state *);
+	int (*set_vring_addr)(struct vhost_device_ctx, struct vhost_vring_addr *);
+	int (*set_vring_base)(struct vhost_device_ctx, struct vhost_vring_state *);
+	int (*get_vring_base)(struct vhost_device_ctx, uint32_t, struct vhost_vring_state *);
 
-	int (* set_vring_kick) 	(struct vhost_device_ctx, struct vhost_vring_file *);
-	int (* set_vring_call) 	(struct vhost_device_ctx, struct vhost_vring_file *);
+	int (*set_vring_kick)(struct vhost_device_ctx, struct vhost_vring_file *);
+	int (*set_vring_call)(struct vhost_device_ctx, struct vhost_vring_file *);
 
-	int (* set_backend) 	(struct vhost_device_ctx, struct vhost_vring_file *);
+	int (*set_backend)(struct vhost_device_ctx, struct vhost_vring_file *);
 
-	int (* set_owner) 		(struct vhost_device_ctx);
-	int (* reset_owner) 	(struct vhost_device_ctx);
+	int (*set_owner)(struct vhost_device_ctx);
+	int (*reset_owner)(struct vhost_device_ctx);
 };
 
 
diff --git a/lib/librte_vhost/vhost_rxtx.c b/lib/librte_vhost/vhost_rxtx.c
index 688e661..7c2c47a 100644
--- a/lib/librte_vhost/vhost_rxtx.c
+++ b/lib/librte_vhost/vhost_rxtx.c
@@ -50,13 +50,14 @@
  * added to the RX queue. This function works when mergeable is disabled.
  */
 static inline uint32_t __attribute__((always_inline))
-virtio_dev_rx(struct virtio_net *dev, uint16_t queue_id, struct rte_mbuf **pkts, uint32_t count)
+virtio_dev_rx(struct virtio_net *dev, uint16_t queue_id,
+	struct rte_mbuf **pkts, uint32_t count)
 {
 	struct vhost_virtqueue *vq;
 	struct vring_desc *desc;
 	struct rte_mbuf *buff;
 	/* The virtio_hdr is initialised to 0. */
-	struct virtio_net_hdr_mrg_rxbuf virtio_hdr = {{0,0,0,0,0,0},0};
+	struct virtio_net_hdr_mrg_rxbuf virtio_hdr = {{0, 0, 0, 0, 0, 0}, 0};
 	uint64_t buff_addr = 0;
 	uint64_t buff_hdr_addr = 0;
 	uint32_t head[VHOST_MAX_PKT_BURST], packet_len = 0;
@@ -74,7 +75,10 @@ virtio_dev_rx(struct virtio_net *dev, uint16_t queue_id, struct rte_mbuf **pkts,
 
 	vq = dev->virtqueue[VIRTIO_RXQ];
 	count = (count > VHOST_MAX_PKT_BURST) ? VHOST_MAX_PKT_BURST : count;
-	/* As many data cores may want access to available buffers, they need to be reserved. */
+	/*
+	 * As many data cores may want access to available buffers,
+	 * they need to be reserved.
+	 */
 	do {
 		res_base_idx = vq->last_used_idx_res;
 		avail_idx = *((volatile uint16_t *)&vq->avail->idx);
@@ -89,20 +93,22 @@ virtio_dev_rx(struct virtio_net *dev, uint16_t queue_id, struct rte_mbuf **pkts,
 
 		res_end_idx = res_base_idx + count;
 		/* vq->last_used_idx_res is atomically updated. */
-		/* TODO: Allow to disable cmpset if no concurrency in application */
+		/* TODO: Allow to disable cmpset if no concurrency in application. */
 		success = rte_atomic16_cmpset(&vq->last_used_idx_res,
 				res_base_idx, res_end_idx);
 		/* If there is contention here and failed, try again. */
 	} while (unlikely(success == 0));
 	res_cur_idx = res_base_idx;
-	LOG_DEBUG(VHOST_DATA, "(%"PRIu64") Current Index %d| End Index %d\n", dev->device_fh, res_cur_idx, res_end_idx);
+	LOG_DEBUG(VHOST_DATA, "(%"PRIu64") Current Index %d| End Index %d\n",
+			dev->device_fh, res_cur_idx, res_end_idx);
 
 	/* Prefetch available ring to retrieve indexes. */
 	rte_prefetch0(&vq->avail->ring[res_cur_idx & (vq->size - 1)]);
 
 	/* Retrieve all of the head indexes first to avoid caching issues. */
 	for (head_idx = 0; head_idx < count; head_idx++)
-		head[head_idx] = vq->avail->ring[(res_cur_idx + head_idx) & (vq->size - 1)];
+		head[head_idx] = vq->avail->ring[(res_cur_idx + head_idx) &
+					(vq->size - 1)];
 
 	/*Prefetch descriptor index. */
 	rte_prefetch0(&vq->desc[head[packet_success]]);
@@ -113,18 +119,18 @@ virtio_dev_rx(struct virtio_net *dev, uint16_t queue_id, struct rte_mbuf **pkts,
 
 		buff = pkts[packet_success];
 
-		/* Convert from gpa to vva (guest physical addr -> vhost virtual addr) */
+		/* gpa to vva (guest physical addr -> vhost virtual addr) */
 		buff_addr = gpa_to_vva(dev, desc->addr);
 		/* Prefetch buffer address. */
-		rte_prefetch0((void*)(uintptr_t)buff_addr);
+		rte_prefetch0((void *)(uintptr_t)buff_addr);
 
 		/* Copy virtio_hdr to packet and increment buffer address */
 		buff_hdr_addr = buff_addr;
 		packet_len = rte_pktmbuf_data_len(buff) + vq->vhost_hlen;
 
 		/*
-		 * If the descriptors are chained the header and data are placed in
-		 * separate buffers.
+		 * If the descriptors are chained the header and data are
+		 * placed in separate buffers.
 		 */
 		if (desc->flags & VRING_DESC_F_NEXT) {
 			desc->len = vq->vhost_hlen;
@@ -143,7 +149,7 @@ virtio_dev_rx(struct virtio_net *dev, uint16_t queue_id, struct rte_mbuf **pkts,
 		vq->used->ring[res_cur_idx & (vq->size - 1)].len = packet_len;
 
 		/* Copy mbuf data to buffer */
-		/* TODO fixme for sg mbuf and the case that desc couldn't hold the mbuf data */
+		/* FIXME for sg mbuf and the case that desc couldn't hold the mbuf data */
 		rte_memcpy((void *)(uintptr_t)buff_addr,
 			rte_pktmbuf_mtod(buff, const void *),
 			rte_pktmbuf_data_len(buff));
@@ -152,10 +158,11 @@ virtio_dev_rx(struct virtio_net *dev, uint16_t queue_id, struct rte_mbuf **pkts,
 
 		res_cur_idx++;
 		packet_success++;
-	
-		rte_memcpy((void *)(uintptr_t)buff_hdr_addr, (const void *)&virtio_hdr,
-				vq->vhost_hlen);
-		VHOST_PRINT_PACKET(dev, (uintptr_t)buff_hdr_addr, vq->vhost_hlen, 1);
+
+		rte_memcpy((void *)(uintptr_t)buff_hdr_addr,
+			(const void *)&virtio_hdr, vq->vhost_hlen);
+		VHOST_PRINT_PACKET(dev, (uintptr_t)buff_hdr_addr,
+				vq->vhost_hlen, 1);
 		if (res_cur_idx < res_end_idx) {
 			/* Prefetch descriptor index. */
 			rte_prefetch0(&vq->desc[head[packet_success]]);
@@ -386,8 +393,8 @@ copy_from_mbuf_to_vring(struct virtio_net *dev, uint16_t res_base_idx,
  * This function works for mergeable RX.
  */
 static inline uint32_t __attribute__((always_inline))
-virtio_dev_merge_rx(struct virtio_net *dev, uint16_t queue_id, struct rte_mbuf **pkts,
-	uint32_t count)
+virtio_dev_merge_rx(struct virtio_net *dev, uint16_t queue_id,
+	struct rte_mbuf **pkts, uint32_t count)
 {
 	struct vhost_virtqueue *vq;
 	uint32_t pkt_idx = 0, entry_success = 0;
@@ -507,7 +514,8 @@ virtio_dev_merge_rx(struct virtio_net *dev, uint16_t queue_id, struct rte_mbuf *
 }
 
 uint32_t
-rte_vhost_enqueue_burst(struct virtio_net *dev, uint16_t queue_id, struct rte_mbuf **pkts, uint32_t count)
+rte_vhost_enqueue_burst(struct virtio_net *dev, uint16_t queue_id,
+	struct rte_mbuf **pkts, uint32_t count)
 {
 	if (unlikely(dev->features & (1 << VIRTIO_NET_F_MRG_RXBUF)))
 		return virtio_dev_merge_rx(dev, queue_id, pkts, count);
@@ -518,7 +526,8 @@ rte_vhost_enqueue_burst(struct virtio_net *dev, uint16_t queue_id, struct rte_mb
 
 
 uint32_t
-rte_vhost_dequeue_burst(struct virtio_net *dev, uint16_t queue_id, struct rte_mempool *mbuf_pool, struct rte_mbuf **pkts, uint32_t count)
+rte_vhost_dequeue_burst(struct virtio_net *dev, uint16_t queue_id,
+	struct rte_mempool *mbuf_pool, struct rte_mbuf **pkts, uint32_t count)
 {
 	struct rte_mbuf *m, *prev;
 	struct vhost_virtqueue *vq;
@@ -555,7 +564,8 @@ rte_vhost_dequeue_burst(struct virtio_net *dev, uint16_t queue_id, struct rte_me
 	/* Limit to MAX_PKT_BURST. */
 	free_entries = RTE_MIN(free_entries, VHOST_MAX_PKT_BURST);
 
-	LOG_DEBUG(VHOST_DATA, "(%"PRIu64") Buffers available %d\n", dev->device_fh, free_entries);
+	LOG_DEBUG(VHOST_DATA, "(%"PRIu64") Buffers available %d\n",
+			dev->device_fh, free_entries);
 	/* Retrieve all of the head indexes first to avoid caching issues. */
 	for (i = 0; i < free_entries; i++)
 		head[i] = vq->avail->ring[(vq->last_used_idx + i) & (vq->size - 1)];
@@ -596,7 +606,7 @@ rte_vhost_dequeue_burst(struct virtio_net *dev, uint16_t queue_id, struct rte_me
 
 		vb_offset = 0;
 		vb_avail = desc->len;
-		
+
 		seg_avail = 0;
 		/* Allocate an mbuf and populate the structure. */
 		m = rte_pktmbuf_alloc(mbuf_pool);
@@ -611,7 +621,7 @@ rte_vhost_dequeue_burst(struct virtio_net *dev, uint16_t queue_id, struct rte_me
 
 		VHOST_PRINT_PACKET(dev, (uintptr_t)vb_addr, desc->len, 0);
 
-		
+
 		seg_num++;
 		cur = m;
 		prev = m;
@@ -681,7 +691,8 @@ rte_vhost_dequeue_burst(struct virtio_net *dev, uint16_t queue_id, struct rte_me
 						prev->next = cur;
 						prev = cur;
 						seg_offset = 0;
-						seg_avail = cur->buf_len - RTE_PKTMBUF_HEADROOM;
+						seg_avail = cur->buf_len -
+							RTE_PKTMBUF_HEADROOM;
 					}
 
 					desc = &vq->desc[desc->next];
diff --git a/lib/librte_vhost/virtio-net.c b/lib/librte_vhost/virtio-net.c
index 9852961..616af5f 100644
--- a/lib/librte_vhost/virtio-net.c
+++ b/lib/librte_vhost/virtio-net.c
@@ -56,16 +56,16 @@
  * Device linked list structure for configuration.
  */
 struct virtio_net_config_ll {
-	struct virtio_net             dev;    /* Virtio device. */
-	struct virtio_net_config_ll   *next;  /* Next entry on linked list. */
+	struct virtio_net		dev;	/* Virtio device.*/
+	struct virtio_net_config_ll	*next;	/* Next entry on linked list.*/
 };
 
 static const char eventfd_cdev[] = "/dev/eventfd-link";
 
 /* device ops to add/remove device to data core. */
-static struct virtio_net_device_ops const * notify_ops;
+static struct virtio_net_device_ops const *notify_ops;
 /* Root address of the linked list in the configuration core. */
-static struct virtio_net_config_ll			*ll_root = NULL;
+static struct virtio_net_config_ll	*ll_root;
 
 /* Features supported by this library. */
 #define VHOST_SUPPORTED_FEATURES (1ULL << VIRTIO_NET_F_MRG_RXBUF)
@@ -81,16 +81,15 @@ static const uint32_t BUFSIZE = PATH_MAX;
 #define PROCMAP_SZ 8
 
 /* Structure containing information gathered from maps file. */
-struct procmap
-{
-	uint64_t	va_start;			/* Start virtual address in file. */
-	uint64_t	len;				/* Size of file. */
-	uint64_t	pgoff;				/* Not used. */
-	uint32_t	maj;				/* Not used. */
-	uint32_t	min;				/* Not used. */
-	uint32_t	ino;				/* Not used. */
-	char		prot[PROT_SZ];		/* Not used. */
-	char		fname[PATH_MAX];	/* File name. */
+struct procmap {
+	uint64_t	va_start;	/* Start virtual address in file. */
+	uint64_t	len;		/* Size of file. */
+	uint64_t	pgoff;		/* Not used. */
+	uint32_t	maj;		/* Not used. */
+	uint32_t	min;		/* Not used. */
+	uint32_t	ino;		/* Not used. */
+	char		prot[PROT_SZ];	/* Not used. */
+	char		fname[PATH_MAX];/* File name. */
 };
 
 /*
@@ -109,8 +108,9 @@ qva_to_vva(struct virtio_net *dev, uint64_t qemu_va)
 		region = &dev->mem->regions[regionidx];
 		if ((qemu_va >= region->userspace_address) &&
 				(qemu_va <= region->userspace_address +
-			 	region->memory_size)) {
-			vhost_va = dev->mem->mapped_address + qemu_va - dev->mem->base_address;
+				region->memory_size)) {
+			vhost_va = dev->mem->mapped_address + qemu_va -
+					dev->mem->base_address;
 			break;
 		}
 	}
@@ -121,7 +121,8 @@ qva_to_vva(struct virtio_net *dev, uint64_t qemu_va)
  * Locate the file containing QEMU's memory space and map it to our address space.
  */
 static int
-host_memory_map (struct virtio_net *dev, struct virtio_memory *mem, pid_t pid, uint64_t addr)
+host_memory_map(struct virtio_net *dev, struct virtio_memory *mem,
+	pid_t pid, uint64_t addr)
 {
 	struct dirent *dptr = NULL;
 	struct procmap procmap;
@@ -134,20 +135,22 @@ host_memory_map (struct virtio_net *dev, struct virtio_memory *mem, pid_t pid, u
 	char resolved_path[PATH_MAX];
 	FILE		*fmap;
 	void		*map;
-	uint8_t 	found = 0;
-	char 		line[BUFSIZE];
+	uint8_t		found = 0;
+	char		line[BUFSIZE];
 	char dlm[] = "-   :   ";
 	char *str, *sp, *in[PROCMAP_SZ];
 	char *end = NULL;
 
 	/* Path where mem files are located. */
-	snprintf (procdir, PATH_MAX, "/proc/%u/fd/", pid);
+	snprintf(procdir, PATH_MAX, "/proc/%u/fd/", pid);
 	/* Maps file used to locate mem file. */
-	snprintf (mapfile, PATH_MAX, "/proc/%u/maps", pid);
+	snprintf(mapfile, PATH_MAX, "/proc/%u/maps", pid);
 
 	fmap = fopen(mapfile, "r");
 	if (fmap == NULL) {
-		RTE_LOG(ERR, VHOST_CONFIG, "(%"PRIu64") Failed to open maps file for pid %d\n", dev->device_fh, pid);
+		RTE_LOG(ERR, VHOST_CONFIG,
+			"(%"PRIu64") Failed to open maps file for pid %d\n",
+			dev->device_fh, pid);
 		return -1;
 	}
 
@@ -157,7 +160,8 @@ host_memory_map (struct virtio_net *dev, struct virtio_memory *mem, pid_t pid, u
 		errno = 0;
 		/* Split line in to fields. */
 		for (i = 0; i < PROCMAP_SZ; i++) {
-			if (((in[i] = strtok_r(str, &dlm[i], &sp)) == NULL) || (errno != 0)) {
+			in[i] = strtok_r(str, &dlm[i], &sp);
+			if ((in[i] == NULL) || (errno != 0)) {
 				fclose(fmap);
 				return -1;
 			}
@@ -220,7 +224,7 @@ host_memory_map (struct virtio_net *dev, struct virtio_memory *mem, pid_t pid, u
 	/* Find the guest memory file among the process fds. */
 	dp = opendir(procdir);
 	if (dp == NULL) {
-		RTE_LOG(ERR, VHOST_CONFIG, "(%"PRIu64") Cannot open pid %d process directory \n", dev->device_fh, pid);
+		RTE_LOG(ERR, VHOST_CONFIG, "(%"PRIu64") Cannot open pid %d process directory\n", dev->device_fh, pid);
 		return -1;
 
 	}
@@ -229,7 +233,8 @@ host_memory_map (struct virtio_net *dev, struct virtio_memory *mem, pid_t pid, u
 
 	/* Read the fd directory contents. */
 	while (NULL != (dptr = readdir(dp))) {
-		snprintf (memfile, PATH_MAX, "/proc/%u/fd/%s", pid, dptr->d_name);
+		snprintf(memfile, PATH_MAX, "/proc/%u/fd/%s",
+				pid, dptr->d_name);
 	    realpath(memfile, resolved_path);
 		if (resolved_path == NULL) {
 			RTE_LOG(ERR, VHOST_CONFIG, "(%"PRIu64") Failed to resolve fd directory\n", dev->device_fh);
@@ -257,8 +262,9 @@ host_memory_map (struct virtio_net *dev, struct virtio_memory *mem, pid_t pid, u
 		return -1;
 	}
 
-	map = mmap(0, (size_t)procmap.len, PROT_READ|PROT_WRITE , MAP_POPULATE|MAP_SHARED, fd, 0);
-	close (fd);
+	map = mmap(0, (size_t)procmap.len, PROT_READ|PROT_WRITE ,
+			MAP_POPULATE|MAP_SHARED, fd, 0);
+	close(fd);
 
 	if (map == MAP_FAILED) {
 		RTE_LOG(ERR, VHOST_CONFIG, "(%"PRIu64") Error mapping the file %s for pid %d\n",  dev->device_fh, memfile, pid);
@@ -304,9 +310,8 @@ get_device(struct vhost_device_ctx ctx)
 	ll_dev = get_config_ll_entry(ctx);
 
 	/* If a matching entry is found in the linked list, return the device in that entry. */
-	if (ll_dev) {
+	if (ll_dev)
 		return &ll_dev->dev;
-	}
 
 	RTE_LOG(ERR, VHOST_CONFIG, "(%"PRIu64") Device not found in linked list.\n", ctx.fh);
 	return NULL;
@@ -351,7 +356,8 @@ cleanup_device(struct virtio_net *dev)
 {
 	/* Unmap QEMU memory file if mapped. */
 	if (dev->mem) {
-		munmap((void*)(uintptr_t)dev->mem->mapped_address, (size_t)dev->mem->mapped_size);
+		munmap((void *)(uintptr_t)dev->mem->mapped_address,
+			(size_t)dev->mem->mapped_size);
 		free(dev->mem);
 	}
 
@@ -381,7 +387,8 @@ free_device(struct virtio_net_config_ll *ll_dev)
  * Remove an entry from the device configuration linked list.
  */
 static struct virtio_net_config_ll *
-rm_config_ll_entry(struct virtio_net_config_ll *ll_dev, struct virtio_net_config_ll *ll_dev_last)
+rm_config_ll_entry(struct virtio_net_config_ll *ll_dev,
+	struct virtio_net_config_ll *ll_dev_last)
 {
 	/* First remove the device and then clean it up. */
 	if (ll_dev == ll_root) {
@@ -398,7 +405,8 @@ rm_config_ll_entry(struct virtio_net_config_ll *ll_dev, struct virtio_net_config
 		} else {
 			cleanup_device(&ll_dev->dev);
 			free_device(ll_dev);
-			RTE_LOG(ERR, VHOST_CONFIG, "Remove entry from config_ll failed\n");
+			RTE_LOG(ERR, VHOST_CONFIG,
+				"Remove entry from config_ll failed\n");
 			return NULL;
 		}
 	}
@@ -416,7 +424,7 @@ init_device(struct virtio_net *dev)
 	vq_offset = offsetof(struct virtio_net, mem);
 
 	/* Set everything to 0. */
-	memset((void*)(uintptr_t)((uint64_t)(uintptr_t)dev + vq_offset), 0,
+	memset((void *)(uintptr_t)((uint64_t)(uintptr_t)dev + vq_offset), 0,
 		(sizeof(struct virtio_net) - (size_t)vq_offset));
 	memset(dev->virtqueue[VIRTIO_RXQ], 0, sizeof(struct vhost_virtqueue));
 	memset(dev->virtqueue[VIRTIO_TXQ], 0, sizeof(struct vhost_virtqueue));
@@ -440,14 +448,18 @@ new_device(struct vhost_device_ctx ctx)
 	/* Setup device and virtqueues. */
 	new_ll_dev = malloc(sizeof(struct virtio_net_config_ll));
 	if (new_ll_dev == NULL) {
-		RTE_LOG(ERR, VHOST_CONFIG, "(%"PRIu64") Failed to allocate memory for dev.\n", ctx.fh);
+		RTE_LOG(ERR, VHOST_CONFIG,
+			"(%"PRIu64") Failed to allocate memory for dev.\n",
+			ctx.fh);
 		return -1;
 	}
 
 	virtqueue_rx = malloc(sizeof(struct vhost_virtqueue));
 	if (virtqueue_rx == NULL) {
 		free(new_ll_dev);
-		RTE_LOG(ERR, VHOST_CONFIG, "(%"PRIu64") Failed to allocate memory for virtqueue_rx.\n", ctx.fh);
+		RTE_LOG(ERR, VHOST_CONFIG,
+			"(%"PRIu64") Failed to allocate memory for rxq.\n",
+			ctx.fh);
 		return -1;
 	}
 
@@ -455,7 +467,9 @@ new_device(struct vhost_device_ctx ctx)
 	if (virtqueue_tx == NULL) {
 		free(virtqueue_rx);
 		free(new_ll_dev);
-		RTE_LOG(ERR, VHOST_CONFIG, "(%"PRIu64") Failed to allocate memory for virtqueue_tx.\n", ctx.fh);
+		RTE_LOG(ERR, VHOST_CONFIG,
+			"(%"PRIu64") Failed to allocate memory for txq.\n",
+			ctx.fh);
 		return -1;
 	}
 
@@ -573,12 +587,16 @@ set_features(struct vhost_device_ctx ctx, uint64_t *pu)
 	/* Set the vhost_hlen depending on if VIRTIO_NET_F_MRG_RXBUF is set. */
 	if (dev->features & (1 << VIRTIO_NET_F_MRG_RXBUF)) {
 		LOG_DEBUG(VHOST_CONFIG, "(%"PRIu64") Mergeable RX buffers enabled\n", dev->device_fh);
-		dev->virtqueue[VIRTIO_RXQ]->vhost_hlen = sizeof(struct virtio_net_hdr_mrg_rxbuf);
-		dev->virtqueue[VIRTIO_TXQ]->vhost_hlen = sizeof(struct virtio_net_hdr_mrg_rxbuf);
+		dev->virtqueue[VIRTIO_RXQ]->vhost_hlen =
+			sizeof(struct virtio_net_hdr_mrg_rxbuf);
+		dev->virtqueue[VIRTIO_TXQ]->vhost_hlen =
+			sizeof(struct virtio_net_hdr_mrg_rxbuf);
 	} else {
 		LOG_DEBUG(VHOST_CONFIG, "(%"PRIu64") Mergeable RX buffers disabled\n", dev->device_fh);
-		dev->virtqueue[VIRTIO_RXQ]->vhost_hlen = sizeof(struct virtio_net_hdr);
-		dev->virtqueue[VIRTIO_TXQ]->vhost_hlen = sizeof(struct virtio_net_hdr);
+		dev->virtqueue[VIRTIO_RXQ]->vhost_hlen =
+			sizeof(struct virtio_net_hdr);
+		dev->virtqueue[VIRTIO_TXQ]->vhost_hlen =
+			sizeof(struct virtio_net_hdr);
 	}
 	return 0;
 }
@@ -590,7 +608,8 @@ set_features(struct vhost_device_ctx ctx, uint64_t *pu)
  * storing offsets used to translate buffer addresses.
  */
 static int
-set_mem_table(struct vhost_device_ctx ctx, const void *mem_regions_addr, uint32_t nregions)
+set_mem_table(struct vhost_device_ctx ctx, const void *mem_regions_addr,
+	uint32_t nregions)
 {
 	struct virtio_net *dev;
 	struct vhost_memory_region *mem_regions;
@@ -603,12 +622,14 @@ set_mem_table(struct vhost_device_ctx ctx, const void *mem_regions_addr, uint32_
 		return -1;
 
 	if (dev->mem) {
-		munmap((void*)(uintptr_t)dev->mem->mapped_address, (size_t)dev->mem->mapped_size);
+		munmap((void *)(uintptr_t)dev->mem->mapped_address,
+			(size_t)dev->mem->mapped_size);
 		free(dev->mem);
 	}
 
 	/* Malloc the memory structure depending on the number of regions. */
-	mem = calloc(1, sizeof(struct virtio_memory) + (sizeof(struct virtio_memory_regions) * nregions));
+	mem = calloc(1, sizeof(struct virtio_memory) +
+		(sizeof(struct virtio_memory_regions) * nregions));
 	if (mem == NULL) {
 		RTE_LOG(ERR, VHOST_CONFIG, "(%"PRIu64") Failed to allocate memory for dev->mem.\n", dev->device_fh);
 		return -1;
@@ -616,19 +637,24 @@ set_mem_table(struct vhost_device_ctx ctx, const void *mem_regions_addr, uint32_
 
 	mem->nregions = nregions;
 
-	mem_regions = (void*)(uintptr_t)((uint64_t)(uintptr_t)mem_regions_addr + size);
+	mem_regions = (void *)(uintptr_t)
+			((uint64_t)(uintptr_t)mem_regions_addr + size);
 
 	for (regionidx = 0; regionidx < mem->nregions; regionidx++) {
 		/* Populate the region structure for each region. */
-		mem->regions[regionidx].guest_phys_address = mem_regions[regionidx].guest_phys_addr;
-		mem->regions[regionidx].guest_phys_address_end = mem->regions[regionidx].guest_phys_address +
+		mem->regions[regionidx].guest_phys_address =
+			mem_regions[regionidx].guest_phys_addr;
+		mem->regions[regionidx].guest_phys_address_end =
+			mem->regions[regionidx].guest_phys_address +
 			mem_regions[regionidx].memory_size;
-		mem->regions[regionidx].memory_size = mem_regions[regionidx].memory_size;
-		mem->regions[regionidx].userspace_address = mem_regions[regionidx].userspace_addr;
+		mem->regions[regionidx].memory_size =
+			mem_regions[regionidx].memory_size;
+		mem->regions[regionidx].userspace_address =
+			mem_regions[regionidx].userspace_addr;
 
 		LOG_DEBUG(VHOST_CONFIG, "(%"PRIu64") REGION: %u - GPA: %p - QEMU VA: %p - SIZE (%"PRIu64")\n", dev->device_fh,
-				regionidx, (void*)(uintptr_t)mem->regions[regionidx].guest_phys_address,
-				(void*)(uintptr_t)mem->regions[regionidx].userspace_address,
+				regionidx, (void *)(uintptr_t)mem->regions[regionidx].guest_phys_address,
+				(void *)(uintptr_t)mem->regions[regionidx].userspace_address,
 				mem->regions[regionidx].memory_size);
 
 		/*set the base address mapping*/
@@ -728,19 +754,19 @@ set_vring_addr(struct vhost_device_ctx ctx, struct vhost_vring_addr *addr)
 	vq = dev->virtqueue[addr->index];
 
 	/* The addresses are converted from QEMU virtual to Vhost virtual. */
-	vq->desc = (struct vring_desc*)(uintptr_t)qva_to_vva(dev, addr->desc_user_addr);
+	vq->desc = (struct vring_desc *)(uintptr_t)qva_to_vva(dev, addr->desc_user_addr);
 	if (vq->desc == 0) {
 		RTE_LOG(ERR, VHOST_CONFIG, "(%"PRIu64") Failed to find descriptor ring address.\n", dev->device_fh);
 		return -1;
 	}
 
-	vq->avail = (struct vring_avail*)(uintptr_t)qva_to_vva(dev, addr->avail_user_addr);
+	vq->avail = (struct vring_avail *)(uintptr_t)qva_to_vva(dev, addr->avail_user_addr);
 	if (vq->avail == 0) {
 		RTE_LOG(ERR, VHOST_CONFIG, "(%"PRIu64") Failed to find available ring address.\n", dev->device_fh);
 		return -1;
 	}
 
-	vq->used = (struct vring_used*)(uintptr_t)qva_to_vva(dev, addr->used_user_addr);
+	vq->used = (struct vring_used *)(uintptr_t)qva_to_vva(dev, addr->used_user_addr);
 	if (vq->used == 0) {
 		RTE_LOG(ERR, VHOST_CONFIG, "(%"PRIu64") Failed to find used ring address.\n", dev->device_fh);
 		return -1;
@@ -778,7 +804,8 @@ set_vring_base(struct vhost_device_ctx ctx, struct vhost_vring_state *state)
  * We send the virtio device our available ring last used index.
  */
 static int
-get_vring_base(struct vhost_device_ctx ctx, uint32_t index, struct vhost_vring_state *state)
+get_vring_base(struct vhost_device_ctx ctx, uint32_t index,
+	struct vhost_vring_state *state)
 {
 	struct virtio_net *dev;
 
@@ -885,7 +912,7 @@ set_vring_kick(struct vhost_device_ctx ctx, struct vhost_vring_file *file)
 	eventfd_call.target_pid = ctx.pid;
 
 	if (eventfd_copy(dev, &eventfd_call))
-        return -1;
+		return -1;
 
 	return 0;
 }
@@ -903,9 +930,8 @@ set_backend(struct vhost_device_ctx ctx, struct vhost_vring_file *file)
 	struct virtio_net *dev;
 
 	dev = get_device(ctx);
-	if (dev == NULL) {
+	if (dev == NULL)
 		return -1;
-	}
 
 	/* file->index refers to the queue index. The TX queue is 1, RX queue is 0. */
 	dev->virtqueue[file->index]->backend = file->fd;
@@ -917,9 +943,8 @@ set_backend(struct vhost_device_ctx ctx, struct vhost_vring_file *file)
 			return notify_ops->new_device(dev);
 	/* Otherwise we remove it. */
 	} else
-		if (file->fd == VIRTIO_DEV_STOPPED) {
+		if (file->fd == VIRTIO_DEV_STOPPED)
 			notify_ops->destroy_device(dev);
-		}
 	return 0;
 }
 
@@ -927,8 +952,7 @@ set_backend(struct vhost_device_ctx ctx, struct vhost_vring_file *file)
  * Function pointers are set for the device operations to allow CUSE to call functions
  * when an IOCTL, device_add or device_release is received.
  */
-static const struct vhost_net_device_ops vhost_device_ops =
-{
+static const struct vhost_net_device_ops vhost_device_ops = {
 	.new_device = new_device,
 	.destroy_device = destroy_device,
 
@@ -960,7 +984,8 @@ get_virtio_net_callbacks(void)
 	return &vhost_device_ops;
 }
 
-int rte_vhost_enable_guest_notification(struct virtio_net *dev, uint16_t queue_id, int enable)
+int rte_vhost_enable_guest_notification(struct virtio_net *dev,
+	uint16_t queue_id, int enable)
 {
 	if (enable) {
 		RTE_LOG(ERR, VHOST_CONFIG, "guest notification isn't supported.\n");
-- 
1.8.1.4

^ permalink raw reply	[flat|nested] 23+ messages in thread

* [dpdk-dev] [PATCH v5 07/11] lib/librte_vhost: add vhost support in DPDK makefile
  2014-09-26  9:45 [dpdk-dev] [PATCH v5 00/11] user space vhost library and vhost example Huawei Xie
                   ` (5 preceding siblings ...)
  2014-09-26  9:45 ` [dpdk-dev] [PATCH v5 06/11] lib/librte_vhost: fixes serious coding style issues Huawei Xie
@ 2014-09-26  9:45 ` Huawei Xie
  2014-09-26  9:45 ` [dpdk-dev] [PATCH v5 08/11] examples/vhost: copy old vhost example src file Huawei Xie
                   ` (3 subsequent siblings)
  10 siblings, 0 replies; 23+ messages in thread
From: Huawei Xie @ 2014-09-26  9:45 UTC (permalink / raw)
  To: dev

vhost lib is turned off by default as it requires fuse-devel package.
fuse-devel isn't installed in every linux distribution.
fuse-devel enables user space filesystem/char driver development.
vhost lib contains a user space char driver, which replies on this package.

Signed-off-by: Huawei Xie <huawei.xie@intel.com>
---
 config/common_linuxapp | 8 ++++++++
 lib/Makefile           | 1 +
 mk/rte.app.mk          | 5 +++++
 3 files changed, 14 insertions(+)

diff --git a/config/common_linuxapp b/config/common_linuxapp
index 5bee910..6ac6f35 100644
--- a/config/common_linuxapp
+++ b/config/common_linuxapp
@@ -390,6 +390,14 @@ CONFIG_RTE_KNI_VHOST_DEBUG_RX=n
 CONFIG_RTE_KNI_VHOST_DEBUG_TX=n
 
 #
+# Compile vhost library
+# fuse-devel is needed to run vhost.
+# fuse-devel enables user space char driver development
+#
+CONFIG_RTE_LIBRTE_VHOST=n
+CONFIG_RTE_LIBRTE_VHOST_DEBUG=n
+
+#
 #Compile Xen domain0 support
 #
 CONFIG_RTE_LIBRTE_XEN_DOM0=n
diff --git a/lib/Makefile b/lib/Makefile
index 10c5bb3..007c174 100644
--- a/lib/Makefile
+++ b/lib/Makefile
@@ -60,6 +60,7 @@ DIRS-$(CONFIG_RTE_LIBRTE_METER) += librte_meter
 DIRS-$(CONFIG_RTE_LIBRTE_SCHED) += librte_sched
 DIRS-$(CONFIG_RTE_LIBRTE_KVARGS) += librte_kvargs
 DIRS-$(CONFIG_RTE_LIBRTE_DISTRIBUTOR) += librte_distributor
+DIRS-$(CONFIG_RTE_LIBRTE_VHOST) += librte_vhost
 DIRS-$(CONFIG_RTE_LIBRTE_PORT) += librte_port
 DIRS-$(CONFIG_RTE_LIBRTE_TABLE) += librte_table
 DIRS-$(CONFIG_RTE_LIBRTE_PIPELINE) += librte_pipeline
diff --git a/mk/rte.app.mk b/mk/rte.app.mk
index 34dff2a..285b65c 100644
--- a/mk/rte.app.mk
+++ b/mk/rte.app.mk
@@ -190,6 +190,11 @@ ifeq ($(CONFIG_RTE_LIBRTE_VIRTIO_PMD),y)
 LDLIBS += -lrte_pmd_virtio_uio
 endif
 
+ifeq ($(CONFIG_RTE_LIBRTE_VHOST), y)
+LDLIBS += -lrte_vhost
+LDLIBS += -lfuse
+endif
+
 ifeq ($(CONFIG_RTE_LIBRTE_I40E_PMD),y)
 LDLIBS += -lrte_pmd_i40e
 endif
-- 
1.8.1.4

^ permalink raw reply	[flat|nested] 23+ messages in thread

* [dpdk-dev] [PATCH v5 08/11] examples/vhost: copy old vhost example src file
  2014-09-26  9:45 [dpdk-dev] [PATCH v5 00/11] user space vhost library and vhost example Huawei Xie
                   ` (6 preceding siblings ...)
  2014-09-26  9:45 ` [dpdk-dev] [PATCH v5 07/11] lib/librte_vhost: add vhost support in DPDK makefile Huawei Xie
@ 2014-09-26  9:45 ` Huawei Xie
  2014-09-26  9:45 ` [dpdk-dev] [PATCH v5 09/11] examples/vhost: vhost example based on vhost lib API Huawei Xie
                   ` (2 subsequent siblings)
  10 siblings, 0 replies; 23+ messages in thread
From: Huawei Xie @ 2014-09-26  9:45 UTC (permalink / raw)
  To: dev

copy old vhost example source files without any modification.
The subsequent patch will modify it to use new vhost lib API.

Signed-off-by: Huawei Xie <huawei.xie@intel.com>
---
 examples/vhost/main.c | 3722 +++++++++++++++++++++++++++++++++++++++++++++++++
 examples/vhost/main.h |   86 ++
 2 files changed, 3808 insertions(+)
 create mode 100644 examples/vhost/main.c
 create mode 100644 examples/vhost/main.h

diff --git a/examples/vhost/main.c b/examples/vhost/main.c
new file mode 100644
index 0000000..7d9e6a2
--- /dev/null
+++ b/examples/vhost/main.c
@@ -0,0 +1,3722 @@
+/*-
+ *   BSD LICENSE
+ *
+ *   Copyright(c) 2010-2014 Intel Corporation. All rights reserved.
+ *   All rights reserved.
+ *
+ *   Redistribution and use in source and binary forms, with or without
+ *   modification, are permitted provided that the following conditions
+ *   are met:
+ *
+ *     * Redistributions of source code must retain the above copyright
+ *       notice, this list of conditions and the following disclaimer.
+ *     * Redistributions in binary form must reproduce the above copyright
+ *       notice, this list of conditions and the following disclaimer in
+ *       the documentation and/or other materials provided with the
+ *       distribution.
+ *     * Neither the name of Intel Corporation nor the names of its
+ *       contributors may be used to endorse or promote products derived
+ *       from this software without specific prior written permission.
+ *
+ *   THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ *   "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ *   LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+ *   A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+ *   OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+ *   SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+ *   LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+ *   DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+ *   THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ *   (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+ *   OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#include <arpa/inet.h>
+#include <getopt.h>
+#include <linux/if_ether.h>
+#include <linux/if_vlan.h>
+#include <linux/virtio_net.h>
+#include <linux/virtio_ring.h>
+#include <signal.h>
+#include <stdint.h>
+#include <sys/eventfd.h>
+#include <sys/param.h>
+#include <unistd.h>
+
+#include <rte_atomic.h>
+#include <rte_cycles.h>
+#include <rte_ethdev.h>
+#include <rte_log.h>
+#include <rte_string_fns.h>
+#include <rte_malloc.h>
+
+#include "main.h"
+#include "virtio-net.h"
+#include "vhost-net-cdev.h"
+
+#define MAX_QUEUES 128
+
+/* the maximum number of external ports supported */
+#define MAX_SUP_PORTS 1
+
+/*
+ * Calculate the number of buffers needed per port
+ */
+#define NUM_MBUFS_PER_PORT ((MAX_QUEUES*RTE_TEST_RX_DESC_DEFAULT) +  		\
+							(num_switching_cores*MAX_PKT_BURST) +  			\
+							(num_switching_cores*RTE_TEST_TX_DESC_DEFAULT) +\
+							(num_switching_cores*MBUF_CACHE_SIZE))
+
+#define MBUF_CACHE_SIZE 128
+#define MBUF_SIZE (2048 + sizeof(struct rte_mbuf) + RTE_PKTMBUF_HEADROOM)
+
+/*
+ * No frame data buffer allocated from host are required for zero copy
+ * implementation, guest will allocate the frame data buffer, and vhost
+ * directly use it.
+ */
+#define VIRTIO_DESCRIPTOR_LEN_ZCP 1518
+#define MBUF_SIZE_ZCP (VIRTIO_DESCRIPTOR_LEN_ZCP + sizeof(struct rte_mbuf) \
+	+ RTE_PKTMBUF_HEADROOM)
+#define MBUF_CACHE_SIZE_ZCP 0
+
+/*
+ * RX and TX Prefetch, Host, and Write-back threshold values should be
+ * carefully set for optimal performance. Consult the network
+ * controller's datasheet and supporting DPDK documentation for guidance
+ * on how these parameters should be set.
+ */
+#define RX_PTHRESH 8 /* Default values of RX prefetch threshold reg. */
+#define RX_HTHRESH 8 /* Default values of RX host threshold reg. */
+#define RX_WTHRESH 4 /* Default values of RX write-back threshold reg. */
+
+/*
+ * These default values are optimized for use with the Intel(R) 82599 10 GbE
+ * Controller and the DPDK ixgbe PMD. Consider using other values for other
+ * network controllers and/or network drivers.
+ */
+#define TX_PTHRESH 36 /* Default values of TX prefetch threshold reg. */
+#define TX_HTHRESH 0  /* Default values of TX host threshold reg. */
+#define TX_WTHRESH 0  /* Default values of TX write-back threshold reg. */
+
+#define MAX_PKT_BURST 32 		/* Max burst size for RX/TX */
+#define MAX_MRG_PKT_BURST 16 	/* Max burst for merge buffers. Set to 1 due to performance issue. */
+#define BURST_TX_DRAIN_US 100 	/* TX drain every ~100us */
+
+#define BURST_RX_WAIT_US 15 	/* Defines how long we wait between retries on RX */
+#define BURST_RX_RETRIES 4		/* Number of retries on RX. */
+
+#define JUMBO_FRAME_MAX_SIZE    0x2600
+
+/* State of virtio device. */
+#define DEVICE_MAC_LEARNING 0
+#define DEVICE_RX			1
+#define DEVICE_SAFE_REMOVE	2
+
+/* Config_core_flag status definitions. */
+#define REQUEST_DEV_REMOVAL 1
+#define ACK_DEV_REMOVAL 0
+
+/* Configurable number of RX/TX ring descriptors */
+#define RTE_TEST_RX_DESC_DEFAULT 1024
+#define RTE_TEST_TX_DESC_DEFAULT 512
+
+/*
+ * Need refine these 2 macros for legacy and DPDK based front end:
+ * Max vring avail descriptor/entries from guest - MAX_PKT_BURST
+ * And then adjust power 2.
+ */
+/*
+ * For legacy front end, 128 descriptors,
+ * half for virtio header, another half for mbuf.
+ */
+#define RTE_TEST_RX_DESC_DEFAULT_ZCP 32   /* legacy: 32, DPDK virt FE: 128. */
+#define RTE_TEST_TX_DESC_DEFAULT_ZCP 64   /* legacy: 64, DPDK virt FE: 64.  */
+
+/* Get first 4 bytes in mbuf headroom. */
+#define MBUF_HEADROOM_UINT32(mbuf) (*(uint32_t *)((uint8_t *)(mbuf) \
+		+ sizeof(struct rte_mbuf)))
+
+/* true if x is a power of 2 */
+#define POWEROF2(x) ((((x)-1) & (x)) == 0)
+
+#define INVALID_PORT_ID 0xFF
+
+/* Max number of devices. Limited by vmdq. */
+#define MAX_DEVICES 64
+
+/* Size of buffers used for snprintfs. */
+#define MAX_PRINT_BUFF 6072
+
+/* Maximum character device basename size. */
+#define MAX_BASENAME_SZ 10
+
+/* Maximum long option length for option parsing. */
+#define MAX_LONG_OPT_SZ 64
+
+/* Used to compare MAC addresses. */
+#define MAC_ADDR_CMP 0xFFFFFFFFFFFFULL
+
+/* Number of descriptors per cacheline. */
+#define DESC_PER_CACHELINE (CACHE_LINE_SIZE / sizeof(struct vring_desc))
+
+/* mask of enabled ports */
+static uint32_t enabled_port_mask = 0;
+
+/*Number of switching cores enabled*/
+static uint32_t num_switching_cores = 0;
+
+/* number of devices/queues to support*/
+static uint32_t num_queues = 0;
+uint32_t num_devices = 0;
+
+/*
+ * Enable zero copy, pkts buffer will directly dma to hw descriptor,
+ * disabled on default.
+ */
+static uint32_t zero_copy;
+
+/* number of descriptors to apply*/
+static uint32_t num_rx_descriptor = RTE_TEST_RX_DESC_DEFAULT_ZCP;
+static uint32_t num_tx_descriptor = RTE_TEST_TX_DESC_DEFAULT_ZCP;
+
+/* max ring descriptor, ixgbe, i40e, e1000 all are 4096. */
+#define MAX_RING_DESC 4096
+
+struct vpool {
+	struct rte_mempool *pool;
+	struct rte_ring *ring;
+	uint32_t buf_size;
+} vpool_array[MAX_QUEUES+MAX_QUEUES];
+
+/* Enable VM2VM communications. If this is disabled then the MAC address compare is skipped. */
+typedef enum {
+	VM2VM_DISABLED = 0,
+	VM2VM_SOFTWARE = 1,
+	VM2VM_HARDWARE = 2,
+	VM2VM_LAST
+} vm2vm_type;
+static vm2vm_type vm2vm_mode = VM2VM_SOFTWARE;
+
+/* The type of host physical address translated from guest physical address. */
+typedef enum {
+	PHYS_ADDR_CONTINUOUS = 0,
+	PHYS_ADDR_CROSS_SUBREG = 1,
+	PHYS_ADDR_INVALID = 2,
+	PHYS_ADDR_LAST
+} hpa_type;
+
+/* Enable stats. */
+static uint32_t enable_stats = 0;
+/* Enable retries on RX. */
+static uint32_t enable_retry = 1;
+/* Specify timeout (in useconds) between retries on RX. */
+static uint32_t burst_rx_delay_time = BURST_RX_WAIT_US;
+/* Specify the number of retries on RX. */
+static uint32_t burst_rx_retry_num = BURST_RX_RETRIES;
+
+/* Character device basename. Can be set by user. */
+static char dev_basename[MAX_BASENAME_SZ] = "vhost-net";
+
+/* Charater device index. Can be set by user. */
+static uint32_t dev_index = 0;
+
+/* This can be set by the user so it is made available here. */
+extern uint64_t VHOST_FEATURES;
+
+/* Default configuration for rx and tx thresholds etc. */
+static struct rte_eth_rxconf rx_conf_default = {
+	.rx_thresh = {
+		.pthresh = RX_PTHRESH,
+		.hthresh = RX_HTHRESH,
+		.wthresh = RX_WTHRESH,
+	},
+	.rx_drop_en = 1,
+};
+
+/*
+ * These default values are optimized for use with the Intel(R) 82599 10 GbE
+ * Controller and the DPDK ixgbe/igb PMD. Consider using other values for other
+ * network controllers and/or network drivers.
+ */
+static struct rte_eth_txconf tx_conf_default = {
+	.tx_thresh = {
+		.pthresh = TX_PTHRESH,
+		.hthresh = TX_HTHRESH,
+		.wthresh = TX_WTHRESH,
+	},
+	.tx_free_thresh = 0, /* Use PMD default values */
+	.tx_rs_thresh = 0, /* Use PMD default values */
+};
+
+/* empty vmdq configuration structure. Filled in programatically */
+static struct rte_eth_conf vmdq_conf_default = {
+	.rxmode = {
+		.mq_mode        = ETH_MQ_RX_VMDQ_ONLY,
+		.split_hdr_size = 0,
+		.header_split   = 0, /**< Header Split disabled */
+		.hw_ip_checksum = 0, /**< IP checksum offload disabled */
+		.hw_vlan_filter = 0, /**< VLAN filtering disabled */
+		/*
+		 * It is necessary for 1G NIC such as I350,
+		 * this fixes bug of ipv4 forwarding in guest can't
+		 * forward pakets from one virtio dev to another virtio dev.
+		 */
+		.hw_vlan_strip  = 1, /**< VLAN strip enabled. */
+		.jumbo_frame    = 0, /**< Jumbo Frame Support disabled */
+		.hw_strip_crc   = 0, /**< CRC stripped by hardware */
+	},
+
+	.txmode = {
+		.mq_mode = ETH_MQ_TX_NONE,
+	},
+	.rx_adv_conf = {
+		/*
+		 * should be overridden separately in code with
+		 * appropriate values
+		 */
+		.vmdq_rx_conf = {
+			.nb_queue_pools = ETH_8_POOLS,
+			.enable_default_pool = 0,
+			.default_pool = 0,
+			.nb_pool_maps = 0,
+			.pool_map = {{0, 0},},
+		},
+	},
+};
+
+static unsigned lcore_ids[RTE_MAX_LCORE];
+static uint8_t ports[RTE_MAX_ETHPORTS];
+static unsigned num_ports = 0; /**< The number of ports specified in command line */
+
+static const uint16_t external_pkt_default_vlan_tag = 2000;
+const uint16_t vlan_tags[] = {
+	1000, 1001, 1002, 1003, 1004, 1005, 1006, 1007,
+	1008, 1009, 1010, 1011,	1012, 1013, 1014, 1015,
+	1016, 1017, 1018, 1019, 1020, 1021, 1022, 1023,
+	1024, 1025, 1026, 1027, 1028, 1029, 1030, 1031,
+	1032, 1033, 1034, 1035, 1036, 1037, 1038, 1039,
+	1040, 1041, 1042, 1043, 1044, 1045, 1046, 1047,
+	1048, 1049, 1050, 1051, 1052, 1053, 1054, 1055,
+	1056, 1057, 1058, 1059, 1060, 1061, 1062, 1063,
+};
+
+/* ethernet addresses of ports */
+static struct ether_addr vmdq_ports_eth_addr[RTE_MAX_ETHPORTS];
+
+/* heads for the main used and free linked lists for the data path. */
+static struct virtio_net_data_ll *ll_root_used = NULL;
+static struct virtio_net_data_ll *ll_root_free = NULL;
+
+/* Array of data core structures containing information on individual core linked lists. */
+static struct lcore_info lcore_info[RTE_MAX_LCORE];
+
+/* Used for queueing bursts of TX packets. */
+struct mbuf_table {
+	unsigned len;
+	unsigned txq_id;
+	struct rte_mbuf *m_table[MAX_PKT_BURST];
+};
+
+/* TX queue for each data core. */
+struct mbuf_table lcore_tx_queue[RTE_MAX_LCORE];
+
+/* TX queue fori each virtio device for zero copy. */
+struct mbuf_table tx_queue_zcp[MAX_QUEUES];
+
+/* Vlan header struct used to insert vlan tags on TX. */
+struct vlan_ethhdr {
+	unsigned char   h_dest[ETH_ALEN];
+	unsigned char   h_source[ETH_ALEN];
+	__be16          h_vlan_proto;
+	__be16          h_vlan_TCI;
+	__be16          h_vlan_encapsulated_proto;
+};
+
+/* IPv4 Header */
+struct ipv4_hdr {
+	uint8_t  version_ihl;		/**< version and header length */
+	uint8_t  type_of_service;	/**< type of service */
+	uint16_t total_length;		/**< length of packet */
+	uint16_t packet_id;		/**< packet ID */
+	uint16_t fragment_offset;	/**< fragmentation offset */
+	uint8_t  time_to_live;		/**< time to live */
+	uint8_t  next_proto_id;		/**< protocol ID */
+	uint16_t hdr_checksum;		/**< header checksum */
+	uint32_t src_addr;		/**< source address */
+	uint32_t dst_addr;		/**< destination address */
+} __attribute__((__packed__));
+
+/* Header lengths. */
+#define VLAN_HLEN       4
+#define VLAN_ETH_HLEN   18
+
+/* Per-device statistics struct */
+struct device_statistics {
+	uint64_t tx_total;
+	rte_atomic64_t rx_total_atomic;
+	uint64_t rx_total;
+	uint64_t tx;
+	rte_atomic64_t rx_atomic;
+	uint64_t rx;
+} __rte_cache_aligned;
+struct device_statistics dev_statistics[MAX_DEVICES];
+
+/*
+ * Builds up the correct configuration for VMDQ VLAN pool map
+ * according to the pool & queue limits.
+ */
+static inline int
+get_eth_conf(struct rte_eth_conf *eth_conf, uint32_t num_devices)
+{
+	struct rte_eth_vmdq_rx_conf conf;
+	unsigned i;
+
+	memset(&conf, 0, sizeof(conf));
+	conf.nb_queue_pools = (enum rte_eth_nb_pools)num_devices;
+	conf.nb_pool_maps = num_devices;
+	conf.enable_loop_back =
+		vmdq_conf_default.rx_adv_conf.vmdq_rx_conf.enable_loop_back;
+
+	for (i = 0; i < conf.nb_pool_maps; i++) {
+		conf.pool_map[i].vlan_id = vlan_tags[ i ];
+		conf.pool_map[i].pools = (1UL << i);
+	}
+
+	(void)(rte_memcpy(eth_conf, &vmdq_conf_default, sizeof(*eth_conf)));
+	(void)(rte_memcpy(&eth_conf->rx_adv_conf.vmdq_rx_conf, &conf,
+		   sizeof(eth_conf->rx_adv_conf.vmdq_rx_conf)));
+	return 0;
+}
+
+/*
+ * Validate the device number according to the max pool number gotten form
+ * dev_info. If the device number is invalid, give the error message and
+ * return -1. Each device must have its own pool.
+ */
+static inline int
+validate_num_devices(uint32_t max_nb_devices)
+{
+	if (num_devices > max_nb_devices) {
+		RTE_LOG(ERR, VHOST_PORT, "invalid number of devices\n");
+		return -1;
+	}
+	return 0;
+}
+
+/*
+ * Initialises a given port using global settings and with the rx buffers
+ * coming from the mbuf_pool passed as parameter
+ */
+static inline int
+port_init(uint8_t port)
+{
+	struct rte_eth_dev_info dev_info;
+	struct rte_eth_conf port_conf;
+	uint16_t rx_rings, tx_rings;
+	uint16_t rx_ring_size, tx_ring_size;
+	int retval;
+	uint16_t q;
+
+	/* The max pool number from dev_info will be used to validate the pool number specified in cmd line */
+	rte_eth_dev_info_get (port, &dev_info);
+
+	/*configure the number of supported virtio devices based on VMDQ limits */
+	num_devices = dev_info.max_vmdq_pools;
+	num_queues = dev_info.max_rx_queues;
+
+	if (zero_copy) {
+		rx_ring_size = num_rx_descriptor;
+		tx_ring_size = num_tx_descriptor;
+		tx_rings = dev_info.max_tx_queues;
+	} else {
+		rx_ring_size = RTE_TEST_RX_DESC_DEFAULT;
+		tx_ring_size = RTE_TEST_TX_DESC_DEFAULT;
+		tx_rings = (uint16_t)rte_lcore_count();
+	}
+
+	retval = validate_num_devices(MAX_DEVICES);
+	if (retval < 0)
+		return retval;
+
+	/* Get port configuration. */
+	retval = get_eth_conf(&port_conf, num_devices);
+	if (retval < 0)
+		return retval;
+
+	if (port >= rte_eth_dev_count()) return -1;
+
+	rx_rings = (uint16_t)num_queues,
+	/* Configure ethernet device. */
+	retval = rte_eth_dev_configure(port, rx_rings, tx_rings, &port_conf);
+	if (retval != 0)
+		return retval;
+
+	/* Setup the queues. */
+	for (q = 0; q < rx_rings; q ++) {
+		retval = rte_eth_rx_queue_setup(port, q, rx_ring_size,
+						rte_eth_dev_socket_id(port), &rx_conf_default,
+						vpool_array[q].pool);
+		if (retval < 0)
+			return retval;
+	}
+	for (q = 0; q < tx_rings; q ++) {
+		retval = rte_eth_tx_queue_setup(port, q, tx_ring_size,
+						rte_eth_dev_socket_id(port), &tx_conf_default);
+		if (retval < 0)
+			return retval;
+	}
+
+	/* Start the device. */
+	retval  = rte_eth_dev_start(port);
+	if (retval < 0) {
+		RTE_LOG(ERR, VHOST_DATA, "Failed to start the device.\n");
+		return retval;
+	}
+
+	rte_eth_macaddr_get(port, &vmdq_ports_eth_addr[port]);
+	RTE_LOG(INFO, VHOST_PORT, "Max virtio devices supported: %u\n", num_devices);
+	RTE_LOG(INFO, VHOST_PORT, "Port %u MAC: %02"PRIx8" %02"PRIx8" %02"PRIx8
+			" %02"PRIx8" %02"PRIx8" %02"PRIx8"\n",
+			(unsigned)port,
+			vmdq_ports_eth_addr[port].addr_bytes[0],
+			vmdq_ports_eth_addr[port].addr_bytes[1],
+			vmdq_ports_eth_addr[port].addr_bytes[2],
+			vmdq_ports_eth_addr[port].addr_bytes[3],
+			vmdq_ports_eth_addr[port].addr_bytes[4],
+			vmdq_ports_eth_addr[port].addr_bytes[5]);
+
+	return 0;
+}
+
+/*
+ * Set character device basename.
+ */
+static int
+us_vhost_parse_basename(const char *q_arg)
+{
+	/* parse number string */
+
+	if (strnlen(q_arg, MAX_BASENAME_SZ) > MAX_BASENAME_SZ)
+		return -1;
+	else
+		snprintf((char*)&dev_basename, MAX_BASENAME_SZ, "%s", q_arg);
+
+	return 0;
+}
+
+/*
+ * Parse the portmask provided at run time.
+ */
+static int
+parse_portmask(const char *portmask)
+{
+	char *end = NULL;
+	unsigned long pm;
+
+	errno = 0;
+
+	/* parse hexadecimal string */
+	pm = strtoul(portmask, &end, 16);
+	if ((portmask[0] == '\0') || (end == NULL) || (*end != '\0') || (errno != 0))
+		return -1;
+
+	if (pm == 0)
+		return -1;
+
+	return pm;
+
+}
+
+/*
+ * Parse num options at run time.
+ */
+static int
+parse_num_opt(const char *q_arg, uint32_t max_valid_value)
+{
+	char *end = NULL;
+	unsigned long num;
+
+	errno = 0;
+
+	/* parse unsigned int string */
+	num = strtoul(q_arg, &end, 10);
+	if ((q_arg[0] == '\0') || (end == NULL) || (*end != '\0') || (errno != 0))
+		return -1;
+
+	if (num > max_valid_value)
+		return -1;
+
+	return num;
+
+}
+
+/*
+ * Display usage
+ */
+static void
+us_vhost_usage(const char *prgname)
+{
+	RTE_LOG(INFO, VHOST_CONFIG, "%s [EAL options] -- -p PORTMASK\n"
+	"		--vm2vm [0|1|2]\n"
+	"		--rx_retry [0|1] --mergeable [0|1] --stats [0-N]\n"
+	"		--dev-basename <name> --dev-index [0-N]\n"
+	"		--nb-devices ND\n"
+	"		-p PORTMASK: Set mask for ports to be used by application\n"
+	"		--vm2vm [0|1|2]: disable/software(default)/hardware vm2vm comms\n"
+	"		--rx-retry [0|1]: disable/enable(default) retries on rx. Enable retry if destintation queue is full\n"
+	"		--rx-retry-delay [0-N]: timeout(in usecond) between retries on RX. This makes effect only if retries on rx enabled\n"
+	"		--rx-retry-num [0-N]: the number of retries on rx. This makes effect only if retries on rx enabled\n"
+	"		--mergeable [0|1]: disable(default)/enable RX mergeable buffers\n"
+	"		--stats [0-N]: 0: Disable stats, N: Time in seconds to print stats\n"
+	"		--dev-basename: The basename to be used for the character device.\n"
+	"		--dev-index [0-N]: Defaults to zero if not used. Index is appended to basename.\n"
+	"		--zero-copy [0|1]: disable(default)/enable rx/tx "
+			"zero copy\n"
+	"		--rx-desc-num [0-N]: the number of descriptors on rx, "
+			"used only when zero copy is enabled.\n"
+	"		--tx-desc-num [0-N]: the number of descriptors on tx, "
+			"used only when zero copy is enabled.\n",
+	       prgname);
+}
+
+/*
+ * Parse the arguments given in the command line of the application.
+ */
+static int
+us_vhost_parse_args(int argc, char **argv)
+{
+	int opt, ret;
+	int option_index;
+	unsigned i;
+	const char *prgname = argv[0];
+	static struct option long_option[] = {
+		{"vm2vm", required_argument, NULL, 0},
+		{"rx-retry", required_argument, NULL, 0},
+		{"rx-retry-delay", required_argument, NULL, 0},
+		{"rx-retry-num", required_argument, NULL, 0},
+		{"mergeable", required_argument, NULL, 0},
+		{"stats", required_argument, NULL, 0},
+		{"dev-basename", required_argument, NULL, 0},
+		{"dev-index", required_argument, NULL, 0},
+		{"zero-copy", required_argument, NULL, 0},
+		{"rx-desc-num", required_argument, NULL, 0},
+		{"tx-desc-num", required_argument, NULL, 0},
+		{NULL, 0, 0, 0},
+	};
+
+	/* Parse command line */
+	while ((opt = getopt_long(argc, argv, "p:",long_option, &option_index)) != EOF) {
+		switch (opt) {
+		/* Portmask */
+		case 'p':
+			enabled_port_mask = parse_portmask(optarg);
+			if (enabled_port_mask == 0) {
+				RTE_LOG(INFO, VHOST_CONFIG, "Invalid portmask\n");
+				us_vhost_usage(prgname);
+				return -1;
+			}
+			break;
+
+		case 0:
+			/* Enable/disable vm2vm comms. */
+			if (!strncmp(long_option[option_index].name, "vm2vm",
+				MAX_LONG_OPT_SZ)) {
+				ret = parse_num_opt(optarg, (VM2VM_LAST - 1));
+				if (ret == -1) {
+					RTE_LOG(INFO, VHOST_CONFIG,
+						"Invalid argument for "
+						"vm2vm [0|1|2]\n");
+					us_vhost_usage(prgname);
+					return -1;
+				} else {
+					vm2vm_mode = (vm2vm_type)ret;
+				}
+			}
+
+			/* Enable/disable retries on RX. */
+			if (!strncmp(long_option[option_index].name, "rx-retry", MAX_LONG_OPT_SZ)) {
+				ret = parse_num_opt(optarg, 1);
+				if (ret == -1) {
+					RTE_LOG(INFO, VHOST_CONFIG, "Invalid argument for rx-retry [0|1]\n");
+					us_vhost_usage(prgname);
+					return -1;
+				} else {
+					enable_retry = ret;
+				}
+			}
+
+			/* Specify the retries delay time (in useconds) on RX. */
+			if (!strncmp(long_option[option_index].name, "rx-retry-delay", MAX_LONG_OPT_SZ)) {
+				ret = parse_num_opt(optarg, INT32_MAX);
+				if (ret == -1) {
+					RTE_LOG(INFO, VHOST_CONFIG, "Invalid argument for rx-retry-delay [0-N]\n");
+					us_vhost_usage(prgname);
+					return -1;
+				} else {
+					burst_rx_delay_time = ret;
+				}
+			}
+
+			/* Specify the retries number on RX. */
+			if (!strncmp(long_option[option_index].name, "rx-retry-num", MAX_LONG_OPT_SZ)) {
+				ret = parse_num_opt(optarg, INT32_MAX);
+				if (ret == -1) {
+					RTE_LOG(INFO, VHOST_CONFIG, "Invalid argument for rx-retry-num [0-N]\n");
+					us_vhost_usage(prgname);
+					return -1;
+				} else {
+					burst_rx_retry_num = ret;
+				}
+			}
+
+			/* Enable/disable RX mergeable buffers. */
+			if (!strncmp(long_option[option_index].name, "mergeable", MAX_LONG_OPT_SZ)) {
+				ret = parse_num_opt(optarg, 1);
+				if (ret == -1) {
+					RTE_LOG(INFO, VHOST_CONFIG, "Invalid argument for mergeable [0|1]\n");
+					us_vhost_usage(prgname);
+					return -1;
+				} else {
+					if (ret) {
+						vmdq_conf_default.rxmode.jumbo_frame = 1;
+						vmdq_conf_default.rxmode.max_rx_pkt_len
+							= JUMBO_FRAME_MAX_SIZE;
+						VHOST_FEATURES = (1ULL << VIRTIO_NET_F_MRG_RXBUF);
+					}
+				}
+			}
+
+			/* Enable/disable stats. */
+			if (!strncmp(long_option[option_index].name, "stats", MAX_LONG_OPT_SZ)) {
+				ret = parse_num_opt(optarg, INT32_MAX);
+				if (ret == -1) {
+					RTE_LOG(INFO, VHOST_CONFIG, "Invalid argument for stats [0..N]\n");
+					us_vhost_usage(prgname);
+					return -1;
+				} else {
+					enable_stats = ret;
+				}
+			}
+
+			/* Set character device basename. */
+			if (!strncmp(long_option[option_index].name, "dev-basename", MAX_LONG_OPT_SZ)) {
+				if (us_vhost_parse_basename(optarg) == -1) {
+					RTE_LOG(INFO, VHOST_CONFIG, "Invalid argument for character device basename (Max %d characters)\n", MAX_BASENAME_SZ);
+					us_vhost_usage(prgname);
+					return -1;
+				}
+			}
+
+			/* Set character device index. */
+			if (!strncmp(long_option[option_index].name, "dev-index", MAX_LONG_OPT_SZ)) {
+				ret = parse_num_opt(optarg, INT32_MAX);
+				if (ret == -1) {
+					RTE_LOG(INFO, VHOST_CONFIG, "Invalid argument for character device index [0..N]\n");
+					us_vhost_usage(prgname);
+					return -1;
+				} else
+					dev_index = ret;
+			}
+
+			/* Enable/disable rx/tx zero copy. */
+			if (!strncmp(long_option[option_index].name,
+				"zero-copy", MAX_LONG_OPT_SZ)) {
+				ret = parse_num_opt(optarg, 1);
+				if (ret == -1) {
+					RTE_LOG(INFO, VHOST_CONFIG,
+						"Invalid argument"
+						" for zero-copy [0|1]\n");
+					us_vhost_usage(prgname);
+					return -1;
+				} else
+					zero_copy = ret;
+
+				if (zero_copy) {
+#ifdef RTE_MBUF_SCATTER_GATHER
+					RTE_LOG(ERR, VHOST_CONFIG, "Before running "
+					"zero copy vhost APP, please "
+					"disable RTE_MBUF_SCATTER_GATHER\n"
+					"in config file and then rebuild DPDK "
+					"core lib!\n"
+					"Otherwise please disable zero copy "
+					"flag in command line!\n");
+					return -1;
+#endif
+				}
+			}
+
+			/* Specify the descriptor number on RX. */
+			if (!strncmp(long_option[option_index].name,
+				"rx-desc-num", MAX_LONG_OPT_SZ)) {
+				ret = parse_num_opt(optarg, MAX_RING_DESC);
+				if ((ret == -1) || (!POWEROF2(ret))) {
+					RTE_LOG(INFO, VHOST_CONFIG,
+					"Invalid argument for rx-desc-num[0-N],"
+					"power of 2 required.\n");
+					us_vhost_usage(prgname);
+					return -1;
+				} else {
+					num_rx_descriptor = ret;
+				}
+			}
+
+			/* Specify the descriptor number on TX. */
+			if (!strncmp(long_option[option_index].name,
+				"tx-desc-num", MAX_LONG_OPT_SZ)) {
+				ret = parse_num_opt(optarg, MAX_RING_DESC);
+				if ((ret == -1) || (!POWEROF2(ret))) {
+					RTE_LOG(INFO, VHOST_CONFIG,
+					"Invalid argument for tx-desc-num [0-N],"
+					"power of 2 required.\n");
+					us_vhost_usage(prgname);
+					return -1;
+				} else {
+					num_tx_descriptor = ret;
+				}
+			}
+
+			break;
+
+			/* Invalid option - print options. */
+		default:
+			us_vhost_usage(prgname);
+			return -1;
+		}
+	}
+
+	for (i = 0; i < RTE_MAX_ETHPORTS; i++) {
+		if (enabled_port_mask & (1 << i))
+			ports[num_ports++] = (uint8_t)i;
+	}
+
+	if ((num_ports ==  0) || (num_ports > MAX_SUP_PORTS)) {
+		RTE_LOG(INFO, VHOST_PORT, "Current enabled port number is %u,"
+			"but only %u port can be enabled\n",num_ports, MAX_SUP_PORTS);
+		return -1;
+	}
+
+	if ((zero_copy == 1) && (vm2vm_mode == VM2VM_SOFTWARE)) {
+		RTE_LOG(INFO, VHOST_PORT,
+			"Vhost zero copy doesn't support software vm2vm,"
+			"please specify 'vm2vm 2' to use hardware vm2vm.\n");
+		return -1;
+	}
+
+	if ((zero_copy == 1) && (vmdq_conf_default.rxmode.jumbo_frame == 1)) {
+		RTE_LOG(INFO, VHOST_PORT,
+			"Vhost zero copy doesn't support jumbo frame,"
+			"please specify '--mergeable 0' to disable the "
+			"mergeable feature.\n");
+		return -1;
+	}
+
+	return 0;
+}
+
+/*
+ * Update the global var NUM_PORTS and array PORTS according to system ports number
+ * and return valid ports number
+ */
+static unsigned check_ports_num(unsigned nb_ports)
+{
+	unsigned valid_num_ports = num_ports;
+	unsigned portid;
+
+	if (num_ports > nb_ports) {
+		RTE_LOG(INFO, VHOST_PORT, "\nSpecified port number(%u) exceeds total system port number(%u)\n",
+			num_ports, nb_ports);
+		num_ports = nb_ports;
+	}
+
+	for (portid = 0; portid < num_ports; portid ++) {
+		if (ports[portid] >= nb_ports) {
+			RTE_LOG(INFO, VHOST_PORT, "\nSpecified port ID(%u) exceeds max system port ID(%u)\n",
+				ports[portid], (nb_ports - 1));
+			ports[portid] = INVALID_PORT_ID;
+			valid_num_ports--;
+		}
+	}
+	return valid_num_ports;
+}
+
+/*
+ * Macro to print out packet contents. Wrapped in debug define so that the
+ * data path is not effected when debug is disabled.
+ */
+#ifdef DEBUG
+#define PRINT_PACKET(device, addr, size, header) do {																\
+	char *pkt_addr = (char*)(addr);																					\
+	unsigned int index;																								\
+	char packet[MAX_PRINT_BUFF];																					\
+																													\
+	if ((header))																									\
+		snprintf(packet, MAX_PRINT_BUFF, "(%"PRIu64") Header size %d: ", (device->device_fh), (size));				\
+	else																											\
+		snprintf(packet, MAX_PRINT_BUFF, "(%"PRIu64") Packet size %d: ", (device->device_fh), (size));				\
+	for (index = 0; index < (size); index++) {																		\
+		snprintf(packet + strnlen(packet, MAX_PRINT_BUFF), MAX_PRINT_BUFF - strnlen(packet, MAX_PRINT_BUFF),	\
+			"%02hhx ", pkt_addr[index]);																			\
+	}																												\
+	snprintf(packet + strnlen(packet, MAX_PRINT_BUFF), MAX_PRINT_BUFF - strnlen(packet, MAX_PRINT_BUFF), "\n");	\
+																													\
+	LOG_DEBUG(VHOST_DATA, "%s", packet);																					\
+} while(0)
+#else
+#define PRINT_PACKET(device, addr, size, header) do{} while(0)
+#endif
+
+/*
+ * Function to convert guest physical addresses to vhost virtual addresses. This
+ * is used to convert virtio buffer addresses.
+ */
+static inline uint64_t __attribute__((always_inline))
+gpa_to_vva(struct virtio_net *dev, uint64_t guest_pa)
+{
+	struct virtio_memory_regions *region;
+	uint32_t regionidx;
+	uint64_t vhost_va = 0;
+
+	for (regionidx = 0; regionidx < dev->mem->nregions; regionidx++) {
+		region = &dev->mem->regions[regionidx];
+		if ((guest_pa >= region->guest_phys_address) &&
+			(guest_pa <= region->guest_phys_address_end)) {
+			vhost_va = region->address_offset + guest_pa;
+			break;
+		}
+	}
+	LOG_DEBUG(VHOST_DATA, "(%"PRIu64") GPA %p| VVA %p\n",
+		dev->device_fh, (void*)(uintptr_t)guest_pa, (void*)(uintptr_t)vhost_va);
+
+	return vhost_va;
+}
+
+/*
+ * Function to convert guest physical addresses to vhost physical addresses.
+ * This is used to convert virtio buffer addresses.
+ */
+static inline uint64_t __attribute__((always_inline))
+gpa_to_hpa(struct virtio_net *dev, uint64_t guest_pa,
+	uint32_t buf_len, hpa_type *addr_type)
+{
+	struct virtio_memory_regions_hpa *region;
+	uint32_t regionidx;
+	uint64_t vhost_pa = 0;
+
+	*addr_type = PHYS_ADDR_INVALID;
+
+	for (regionidx = 0; regionidx < dev->mem->nregions_hpa; regionidx++) {
+		region = &dev->mem->regions_hpa[regionidx];
+		if ((guest_pa >= region->guest_phys_address) &&
+			(guest_pa <= region->guest_phys_address_end)) {
+			vhost_pa = region->host_phys_addr_offset + guest_pa;
+			if (likely((guest_pa + buf_len - 1)
+				<= region->guest_phys_address_end))
+				*addr_type = PHYS_ADDR_CONTINUOUS;
+			else
+				*addr_type = PHYS_ADDR_CROSS_SUBREG;
+			break;
+		}
+	}
+
+	LOG_DEBUG(VHOST_DATA, "(%"PRIu64") GPA %p| HPA %p\n",
+		dev->device_fh, (void *)(uintptr_t)guest_pa,
+		(void *)(uintptr_t)vhost_pa);
+
+	return vhost_pa;
+}
+
+/*
+ * This function adds buffers to the virtio devices RX virtqueue. Buffers can
+ * be received from the physical port or from another virtio device. A packet
+ * count is returned to indicate the number of packets that were succesfully
+ * added to the RX queue. This function works when mergeable is disabled.
+ */
+static inline uint32_t __attribute__((always_inline))
+virtio_dev_rx(struct virtio_net *dev, struct rte_mbuf **pkts, uint32_t count)
+{
+	struct vhost_virtqueue *vq;
+	struct vring_desc *desc;
+	struct rte_mbuf *buff;
+	/* The virtio_hdr is initialised to 0. */
+	struct virtio_net_hdr_mrg_rxbuf virtio_hdr = {{0,0,0,0,0,0},0};
+	uint64_t buff_addr = 0;
+	uint64_t buff_hdr_addr = 0;
+	uint32_t head[MAX_PKT_BURST], packet_len = 0;
+	uint32_t head_idx, packet_success = 0;
+	uint32_t retry = 0;
+	uint16_t avail_idx, res_cur_idx;
+	uint16_t res_base_idx, res_end_idx;
+	uint16_t free_entries;
+	uint8_t success = 0;
+
+	LOG_DEBUG(VHOST_DATA, "(%"PRIu64") virtio_dev_rx()\n", dev->device_fh);
+	vq = dev->virtqueue[VIRTIO_RXQ];
+	count = (count > MAX_PKT_BURST) ? MAX_PKT_BURST : count;
+
+	/* As many data cores may want access to available buffers, they need to be reserved. */
+	do {
+		res_base_idx = vq->last_used_idx_res;
+		avail_idx = *((volatile uint16_t *)&vq->avail->idx);
+
+		free_entries = (avail_idx - res_base_idx);
+		/* If retry is enabled and the queue is full then we wait and retry to avoid packet loss. */
+		if (enable_retry && unlikely(count > free_entries)) {
+			for (retry = 0; retry < burst_rx_retry_num; retry++) {
+				rte_delay_us(burst_rx_delay_time);
+				avail_idx =
+					*((volatile uint16_t *)&vq->avail->idx);
+				free_entries = (avail_idx - res_base_idx);
+				if (count <= free_entries)
+					break;
+			}
+		}
+
+		/*check that we have enough buffers*/
+		if (unlikely(count > free_entries))
+			count = free_entries;
+
+		if (count == 0)
+			return 0;
+
+		res_end_idx = res_base_idx + count;
+		/* vq->last_used_idx_res is atomically updated. */
+		success = rte_atomic16_cmpset(&vq->last_used_idx_res, res_base_idx,
+									res_end_idx);
+	} while (unlikely(success == 0));
+	res_cur_idx = res_base_idx;
+	LOG_DEBUG(VHOST_DATA, "(%"PRIu64") Current Index %d| End Index %d\n", dev->device_fh, res_cur_idx, res_end_idx);
+
+	/* Prefetch available ring to retrieve indexes. */
+	rte_prefetch0(&vq->avail->ring[res_cur_idx & (vq->size - 1)]);
+
+	/* Retrieve all of the head indexes first to avoid caching issues. */
+	for (head_idx = 0; head_idx < count; head_idx++)
+		head[head_idx] = vq->avail->ring[(res_cur_idx + head_idx) & (vq->size - 1)];
+
+	/*Prefetch descriptor index. */
+	rte_prefetch0(&vq->desc[head[packet_success]]);
+
+	while (res_cur_idx != res_end_idx) {
+		/* Get descriptor from available ring */
+		desc = &vq->desc[head[packet_success]];
+
+		buff = pkts[packet_success];
+
+		/* Convert from gpa to vva (guest physical addr -> vhost virtual addr) */
+		buff_addr = gpa_to_vva(dev, desc->addr);
+		/* Prefetch buffer address. */
+		rte_prefetch0((void*)(uintptr_t)buff_addr);
+
+		/* Copy virtio_hdr to packet and increment buffer address */
+		buff_hdr_addr = buff_addr;
+		packet_len = rte_pktmbuf_data_len(buff) + vq->vhost_hlen;
+
+		/*
+		 * If the descriptors are chained the header and data are
+		 * placed in separate buffers.
+		 */
+		if (desc->flags & VRING_DESC_F_NEXT) {
+			desc->len = vq->vhost_hlen;
+			desc = &vq->desc[desc->next];
+			/* Buffer address translation. */
+			buff_addr = gpa_to_vva(dev, desc->addr);
+			desc->len = rte_pktmbuf_data_len(buff);
+		} else {
+			buff_addr += vq->vhost_hlen;
+			desc->len = packet_len;
+		}
+
+		/* Update used ring with desc information */
+		vq->used->ring[res_cur_idx & (vq->size - 1)].id = head[packet_success];
+		vq->used->ring[res_cur_idx & (vq->size - 1)].len = packet_len;
+
+		/* Copy mbuf data to buffer */
+		rte_memcpy((void *)(uintptr_t)buff_addr,
+			(const void *)buff->pkt.data,
+			rte_pktmbuf_data_len(buff));
+		PRINT_PACKET(dev, (uintptr_t)buff_addr,
+			rte_pktmbuf_data_len(buff), 0);
+
+		res_cur_idx++;
+		packet_success++;
+
+		rte_memcpy((void *)(uintptr_t)buff_hdr_addr,
+			(const void *)&virtio_hdr, vq->vhost_hlen);
+
+		PRINT_PACKET(dev, (uintptr_t)buff_hdr_addr, vq->vhost_hlen, 1);
+
+		if (res_cur_idx < res_end_idx) {
+			/* Prefetch descriptor index. */
+			rte_prefetch0(&vq->desc[head[packet_success]]);
+		}
+	}
+
+	rte_compiler_barrier();
+
+	/* Wait until it's our turn to add our buffer to the used ring. */
+	while (unlikely(vq->last_used_idx != res_base_idx))
+		rte_pause();
+
+	*(volatile uint16_t *)&vq->used->idx += count;
+	vq->last_used_idx = res_end_idx;
+
+	/* Kick the guest if necessary. */
+	if (!(vq->avail->flags & VRING_AVAIL_F_NO_INTERRUPT))
+		eventfd_write((int)vq->kickfd, 1);
+	return count;
+}
+
+static inline uint32_t __attribute__((always_inline))
+copy_from_mbuf_to_vring(struct virtio_net *dev,
+	uint16_t res_base_idx, uint16_t res_end_idx,
+	struct rte_mbuf *pkt)
+{
+	uint32_t vec_idx = 0;
+	uint32_t entry_success = 0;
+	struct vhost_virtqueue *vq;
+	/* The virtio_hdr is initialised to 0. */
+	struct virtio_net_hdr_mrg_rxbuf virtio_hdr = {
+		{0, 0, 0, 0, 0, 0}, 0};
+	uint16_t cur_idx = res_base_idx;
+	uint64_t vb_addr = 0;
+	uint64_t vb_hdr_addr = 0;
+	uint32_t seg_offset = 0;
+	uint32_t vb_offset = 0;
+	uint32_t seg_avail;
+	uint32_t vb_avail;
+	uint32_t cpy_len, entry_len;
+
+	if (pkt == NULL)
+		return 0;
+
+	LOG_DEBUG(VHOST_DATA, "(%"PRIu64") Current Index %d| "
+		"End Index %d\n",
+		dev->device_fh, cur_idx, res_end_idx);
+
+	/*
+	 * Convert from gpa to vva
+	 * (guest physical addr -> vhost virtual addr)
+	 */
+	vq = dev->virtqueue[VIRTIO_RXQ];
+	vb_addr =
+		gpa_to_vva(dev, vq->buf_vec[vec_idx].buf_addr);
+	vb_hdr_addr = vb_addr;
+
+	/* Prefetch buffer address. */
+	rte_prefetch0((void *)(uintptr_t)vb_addr);
+
+	virtio_hdr.num_buffers = res_end_idx - res_base_idx;
+
+	LOG_DEBUG(VHOST_DATA, "(%"PRIu64") RX: Num merge buffers %d\n",
+		dev->device_fh, virtio_hdr.num_buffers);
+
+	rte_memcpy((void *)(uintptr_t)vb_hdr_addr,
+		(const void *)&virtio_hdr, vq->vhost_hlen);
+
+	PRINT_PACKET(dev, (uintptr_t)vb_hdr_addr, vq->vhost_hlen, 1);
+
+	seg_avail = rte_pktmbuf_data_len(pkt);
+	vb_offset = vq->vhost_hlen;
+	vb_avail =
+		vq->buf_vec[vec_idx].buf_len - vq->vhost_hlen;
+
+	entry_len = vq->vhost_hlen;
+
+	if (vb_avail == 0) {
+		uint32_t desc_idx =
+			vq->buf_vec[vec_idx].desc_idx;
+		vq->desc[desc_idx].len = vq->vhost_hlen;
+
+		if ((vq->desc[desc_idx].flags
+			& VRING_DESC_F_NEXT) == 0) {
+			/* Update used ring with desc information */
+			vq->used->ring[cur_idx & (vq->size - 1)].id
+				= vq->buf_vec[vec_idx].desc_idx;
+			vq->used->ring[cur_idx & (vq->size - 1)].len
+				= entry_len;
+
+			entry_len = 0;
+			cur_idx++;
+			entry_success++;
+		}
+
+		vec_idx++;
+		vb_addr =
+			gpa_to_vva(dev, vq->buf_vec[vec_idx].buf_addr);
+
+		/* Prefetch buffer address. */
+		rte_prefetch0((void *)(uintptr_t)vb_addr);
+		vb_offset = 0;
+		vb_avail = vq->buf_vec[vec_idx].buf_len;
+	}
+
+	cpy_len = RTE_MIN(vb_avail, seg_avail);
+
+	while (cpy_len > 0) {
+		/* Copy mbuf data to vring buffer */
+		rte_memcpy((void *)(uintptr_t)(vb_addr + vb_offset),
+			(const void *)(rte_pktmbuf_mtod(pkt, char*) + seg_offset),
+			cpy_len);
+
+		PRINT_PACKET(dev,
+			(uintptr_t)(vb_addr + vb_offset),
+			cpy_len, 0);
+
+		seg_offset += cpy_len;
+		vb_offset += cpy_len;
+		seg_avail -= cpy_len;
+		vb_avail -= cpy_len;
+		entry_len += cpy_len;
+
+		if (seg_avail != 0) {
+			/*
+			 * The virtio buffer in this vring
+			 * entry reach to its end.
+			 * But the segment doesn't complete.
+			 */
+			if ((vq->desc[vq->buf_vec[vec_idx].desc_idx].flags &
+				VRING_DESC_F_NEXT) == 0) {
+				/* Update used ring with desc information */
+				vq->used->ring[cur_idx & (vq->size - 1)].id
+					= vq->buf_vec[vec_idx].desc_idx;
+				vq->used->ring[cur_idx & (vq->size - 1)].len
+					= entry_len;
+				entry_len = 0;
+				cur_idx++;
+				entry_success++;
+			}
+
+			vec_idx++;
+			vb_addr = gpa_to_vva(dev,
+				vq->buf_vec[vec_idx].buf_addr);
+			vb_offset = 0;
+			vb_avail = vq->buf_vec[vec_idx].buf_len;
+			cpy_len = RTE_MIN(vb_avail, seg_avail);
+		} else {
+			/*
+			 * This current segment complete, need continue to
+			 * check if the whole packet complete or not.
+			 */
+			pkt = pkt->pkt.next;
+			if (pkt != NULL) {
+				/*
+				 * There are more segments.
+				 */
+				if (vb_avail == 0) {
+					/*
+					 * This current buffer from vring is
+					 * used up, need fetch next buffer
+					 * from buf_vec.
+					 */
+					uint32_t desc_idx =
+						vq->buf_vec[vec_idx].desc_idx;
+					vq->desc[desc_idx].len = vb_offset;
+
+					if ((vq->desc[desc_idx].flags &
+						VRING_DESC_F_NEXT) == 0) {
+						uint16_t wrapped_idx =
+							cur_idx & (vq->size - 1);
+						/*
+						 * Update used ring with the
+						 * descriptor information
+						 */
+						vq->used->ring[wrapped_idx].id
+							= desc_idx;
+						vq->used->ring[wrapped_idx].len
+							= entry_len;
+						entry_success++;
+						entry_len = 0;
+						cur_idx++;
+					}
+
+					/* Get next buffer from buf_vec. */
+					vec_idx++;
+					vb_addr = gpa_to_vva(dev,
+						vq->buf_vec[vec_idx].buf_addr);
+					vb_avail =
+						vq->buf_vec[vec_idx].buf_len;
+					vb_offset = 0;
+				}
+
+				seg_offset = 0;
+				seg_avail = rte_pktmbuf_data_len(pkt);
+				cpy_len = RTE_MIN(vb_avail, seg_avail);
+			} else {
+				/*
+				 * This whole packet completes.
+				 */
+				uint32_t desc_idx =
+					vq->buf_vec[vec_idx].desc_idx;
+				vq->desc[desc_idx].len = vb_offset;
+
+				while (vq->desc[desc_idx].flags &
+					VRING_DESC_F_NEXT) {
+					desc_idx = vq->desc[desc_idx].next;
+					 vq->desc[desc_idx].len = 0;
+				}
+
+				/* Update used ring with desc information */
+				vq->used->ring[cur_idx & (vq->size - 1)].id
+					= vq->buf_vec[vec_idx].desc_idx;
+				vq->used->ring[cur_idx & (vq->size - 1)].len
+					= entry_len;
+				entry_len = 0;
+				cur_idx++;
+				entry_success++;
+				seg_avail = 0;
+				cpy_len = RTE_MIN(vb_avail, seg_avail);
+			}
+		}
+	}
+
+	return entry_success;
+}
+
+/*
+ * This function adds buffers to the virtio devices RX virtqueue. Buffers can
+ * be received from the physical port or from another virtio device. A packet
+ * count is returned to indicate the number of packets that were succesfully
+ * added to the RX queue. This function works for mergeable RX.
+ */
+static inline uint32_t __attribute__((always_inline))
+virtio_dev_merge_rx(struct virtio_net *dev, struct rte_mbuf **pkts,
+	uint32_t count)
+{
+	struct vhost_virtqueue *vq;
+	uint32_t pkt_idx = 0, entry_success = 0;
+	uint32_t retry = 0;
+	uint16_t avail_idx, res_cur_idx;
+	uint16_t res_base_idx, res_end_idx;
+	uint8_t success = 0;
+
+	LOG_DEBUG(VHOST_DATA, "(%"PRIu64") virtio_dev_merge_rx()\n",
+		dev->device_fh);
+	vq = dev->virtqueue[VIRTIO_RXQ];
+	count = RTE_MIN((uint32_t)MAX_PKT_BURST, count);
+
+	if (count == 0)
+		return 0;
+
+	for (pkt_idx = 0; pkt_idx < count; pkt_idx++) {
+		uint32_t secure_len = 0;
+		uint16_t need_cnt;
+		uint32_t vec_idx = 0;
+		uint32_t pkt_len = pkts[pkt_idx]->pkt.pkt_len + vq->vhost_hlen;
+		uint16_t i, id;
+
+		do {
+			/*
+			 * As many data cores may want access to available
+			 * buffers, they need to be reserved.
+			 */
+			res_base_idx = vq->last_used_idx_res;
+			res_cur_idx = res_base_idx;
+
+			do {
+				avail_idx = *((volatile uint16_t *)&vq->avail->idx);
+				if (unlikely(res_cur_idx == avail_idx)) {
+					/*
+					 * If retry is enabled and the queue is
+					 * full then we wait and retry to avoid
+					 * packet loss.
+					 */
+					if (enable_retry) {
+						uint8_t cont = 0;
+						for (retry = 0; retry < burst_rx_retry_num; retry++) {
+							rte_delay_us(burst_rx_delay_time);
+							avail_idx =
+								*((volatile uint16_t *)&vq->avail->idx);
+							if (likely(res_cur_idx != avail_idx)) {
+								cont = 1;
+								break;
+							}
+						}
+						if (cont == 1)
+							continue;
+					}
+
+					LOG_DEBUG(VHOST_DATA,
+						"(%"PRIu64") Failed "
+						"to get enough desc from "
+						"vring\n",
+						dev->device_fh);
+					return pkt_idx;
+				} else {
+					uint16_t wrapped_idx =
+						(res_cur_idx) & (vq->size - 1);
+					uint32_t idx =
+						vq->avail->ring[wrapped_idx];
+					uint8_t next_desc;
+
+					do {
+						next_desc = 0;
+						secure_len += vq->desc[idx].len;
+						if (vq->desc[idx].flags &
+							VRING_DESC_F_NEXT) {
+							idx = vq->desc[idx].next;
+							next_desc = 1;
+						}
+					} while (next_desc);
+
+					res_cur_idx++;
+				}
+			} while (pkt_len > secure_len);
+
+			/* vq->last_used_idx_res is atomically updated. */
+			success = rte_atomic16_cmpset(&vq->last_used_idx_res,
+							res_base_idx,
+							res_cur_idx);
+		} while (success == 0);
+
+		id = res_base_idx;
+		need_cnt = res_cur_idx - res_base_idx;
+
+		for (i = 0; i < need_cnt; i++, id++) {
+			uint16_t wrapped_idx = id & (vq->size - 1);
+			uint32_t idx = vq->avail->ring[wrapped_idx];
+			uint8_t next_desc;
+			do {
+				next_desc = 0;
+				vq->buf_vec[vec_idx].buf_addr =
+					vq->desc[idx].addr;
+				vq->buf_vec[vec_idx].buf_len =
+					vq->desc[idx].len;
+				vq->buf_vec[vec_idx].desc_idx = idx;
+				vec_idx++;
+
+				if (vq->desc[idx].flags & VRING_DESC_F_NEXT) {
+					idx = vq->desc[idx].next;
+					next_desc = 1;
+				}
+			} while (next_desc);
+		}
+
+		res_end_idx = res_cur_idx;
+
+		entry_success = copy_from_mbuf_to_vring(dev, res_base_idx,
+			res_end_idx, pkts[pkt_idx]);
+
+		rte_compiler_barrier();
+
+		/*
+		 * Wait until it's our turn to add our buffer
+		 * to the used ring.
+		 */
+		while (unlikely(vq->last_used_idx != res_base_idx))
+			rte_pause();
+
+		*(volatile uint16_t *)&vq->used->idx += entry_success;
+		vq->last_used_idx = res_end_idx;
+
+		/* Kick the guest if necessary. */
+		if (!(vq->avail->flags & VRING_AVAIL_F_NO_INTERRUPT))
+			eventfd_write((int)vq->kickfd, 1);
+	}
+
+	return count;
+}
+
+/*
+ * Compares a packet destination MAC address to a device MAC address.
+ */
+static inline int __attribute__((always_inline))
+ether_addr_cmp(struct ether_addr *ea, struct ether_addr *eb)
+{
+	return (((*(uint64_t *)ea ^ *(uint64_t *)eb) & MAC_ADDR_CMP) == 0);
+}
+
+/*
+ * This function learns the MAC address of the device and registers this along with a
+ * vlan tag to a VMDQ.
+ */
+static int
+link_vmdq(struct virtio_net *dev, struct rte_mbuf *m)
+{
+	struct ether_hdr *pkt_hdr;
+	struct virtio_net_data_ll *dev_ll;
+	int i, ret;
+
+	/* Learn MAC address of guest device from packet */
+	pkt_hdr = (struct ether_hdr *)m->pkt.data;
+
+	dev_ll = ll_root_used;
+
+	while (dev_ll != NULL) {
+		if (ether_addr_cmp(&(pkt_hdr->s_addr), &dev_ll->dev->mac_address)) {
+			RTE_LOG(INFO, VHOST_DATA, "(%"PRIu64") WARNING: This device is using an existing MAC address and has not been registered.\n", dev->device_fh);
+			return -1;
+		}
+		dev_ll = dev_ll->next;
+	}
+
+	for (i = 0; i < ETHER_ADDR_LEN; i++)
+		dev->mac_address.addr_bytes[i] = pkt_hdr->s_addr.addr_bytes[i];
+
+	/* vlan_tag currently uses the device_id. */
+	dev->vlan_tag = vlan_tags[dev->device_fh];
+
+	/* Print out VMDQ registration info. */
+	RTE_LOG(INFO, VHOST_DATA, "(%"PRIu64") MAC_ADDRESS %02x:%02x:%02x:%02x:%02x:%02x and VLAN_TAG %d registered\n",
+		dev->device_fh,
+		dev->mac_address.addr_bytes[0], dev->mac_address.addr_bytes[1],
+		dev->mac_address.addr_bytes[2], dev->mac_address.addr_bytes[3],
+		dev->mac_address.addr_bytes[4], dev->mac_address.addr_bytes[5],
+		dev->vlan_tag);
+
+	/* Register the MAC address. */
+	ret = rte_eth_dev_mac_addr_add(ports[0], &dev->mac_address, (uint32_t)dev->device_fh);
+	if (ret)
+		RTE_LOG(ERR, VHOST_DATA, "(%"PRIu64") Failed to add device MAC address to VMDQ\n",
+					dev->device_fh);
+
+	/* Enable stripping of the vlan tag as we handle routing. */
+	rte_eth_dev_set_vlan_strip_on_queue(ports[0], (uint16_t)dev->vmdq_rx_q, 1);
+
+	/* Set device as ready for RX. */
+	dev->ready = DEVICE_RX;
+
+	return 0;
+}
+
+/*
+ * Removes MAC address and vlan tag from VMDQ. Ensures that nothing is adding buffers to the RX
+ * queue before disabling RX on the device.
+ */
+static inline void
+unlink_vmdq(struct virtio_net *dev)
+{
+	unsigned i = 0;
+	unsigned rx_count;
+	struct rte_mbuf *pkts_burst[MAX_PKT_BURST];
+
+	if (dev->ready == DEVICE_RX) {
+		/*clear MAC and VLAN settings*/
+		rte_eth_dev_mac_addr_remove(ports[0], &dev->mac_address);
+		for (i = 0; i < 6; i++)
+			dev->mac_address.addr_bytes[i] = 0;
+
+		dev->vlan_tag = 0;
+
+		/*Clear out the receive buffers*/
+		rx_count = rte_eth_rx_burst(ports[0],
+					(uint16_t)dev->vmdq_rx_q, pkts_burst, MAX_PKT_BURST);
+
+		while (rx_count) {
+			for (i = 0; i < rx_count; i++)
+				rte_pktmbuf_free(pkts_burst[i]);
+
+			rx_count = rte_eth_rx_burst(ports[0],
+					(uint16_t)dev->vmdq_rx_q, pkts_burst, MAX_PKT_BURST);
+		}
+
+		dev->ready = DEVICE_MAC_LEARNING;
+	}
+}
+
+/*
+ * Check if the packet destination MAC address is for a local device. If so then put
+ * the packet on that devices RX queue. If not then return.
+ */
+static inline unsigned __attribute__((always_inline))
+virtio_tx_local(struct virtio_net *dev, struct rte_mbuf *m)
+{
+	struct virtio_net_data_ll *dev_ll;
+	struct ether_hdr *pkt_hdr;
+	uint64_t ret = 0;
+
+	pkt_hdr = (struct ether_hdr *)m->pkt.data;
+
+	/*get the used devices list*/
+	dev_ll = ll_root_used;
+
+	while (dev_ll != NULL) {
+		if ((dev_ll->dev->ready == DEVICE_RX) && ether_addr_cmp(&(pkt_hdr->d_addr),
+				          &dev_ll->dev->mac_address)) {
+
+			/* Drop the packet if the TX packet is destined for the TX device. */
+			if (dev_ll->dev->device_fh == dev->device_fh) {
+				LOG_DEBUG(VHOST_DATA, "(%"PRIu64") TX: Source and destination MAC addresses are the same. Dropping packet.\n",
+							dev_ll->dev->device_fh);
+				return 0;
+			}
+
+
+			LOG_DEBUG(VHOST_DATA, "(%"PRIu64") TX: MAC address is local\n", dev_ll->dev->device_fh);
+
+			if (dev_ll->dev->remove) {
+				/*drop the packet if the device is marked for removal*/
+				LOG_DEBUG(VHOST_DATA, "(%"PRIu64") Device is marked for removal\n", dev_ll->dev->device_fh);
+			} else {
+				uint32_t mergeable =
+					dev_ll->dev->features &
+					(1 << VIRTIO_NET_F_MRG_RXBUF);
+
+				/*send the packet to the local virtio device*/
+				if (likely(mergeable == 0))
+					ret = virtio_dev_rx(dev_ll->dev, &m, 1);
+				else
+					ret = virtio_dev_merge_rx(dev_ll->dev,
+						&m, 1);
+
+				if (enable_stats) {
+					rte_atomic64_add(
+					&dev_statistics[dev_ll->dev->device_fh].rx_total_atomic,
+					1);
+					rte_atomic64_add(
+					&dev_statistics[dev_ll->dev->device_fh].rx_atomic,
+					ret);
+					dev_statistics[dev->device_fh].tx_total++;
+					dev_statistics[dev->device_fh].tx += ret;
+				}
+			}
+
+			return 0;
+		}
+		dev_ll = dev_ll->next;
+	}
+
+	return -1;
+}
+
+/*
+ * This function routes the TX packet to the correct interface. This may be a local device
+ * or the physical port.
+ */
+static inline void __attribute__((always_inline))
+virtio_tx_route(struct virtio_net* dev, struct rte_mbuf *m, struct rte_mempool *mbuf_pool, uint16_t vlan_tag)
+{
+	struct mbuf_table *tx_q;
+	struct vlan_ethhdr *vlan_hdr;
+	struct rte_mbuf **m_table;
+	struct rte_mbuf *mbuf, *prev;
+	unsigned len, ret, offset = 0;
+	const uint16_t lcore_id = rte_lcore_id();
+	struct virtio_net_data_ll *dev_ll = ll_root_used;
+	struct ether_hdr *pkt_hdr = (struct ether_hdr *)m->pkt.data;
+
+	/*check if destination is local VM*/
+	if ((vm2vm_mode == VM2VM_SOFTWARE) && (virtio_tx_local(dev, m) == 0))
+		return;
+
+	if (vm2vm_mode == VM2VM_HARDWARE) {
+		while (dev_ll != NULL) {
+			if ((dev_ll->dev->ready == DEVICE_RX)
+				&& ether_addr_cmp(&(pkt_hdr->d_addr),
+				&dev_ll->dev->mac_address)) {
+				/*
+				 * Drop the packet if the TX packet is
+				 * destined for the TX device.
+				 */
+				if (dev_ll->dev->device_fh == dev->device_fh) {
+					LOG_DEBUG(VHOST_DATA,
+					"(%"PRIu64") TX: Source and destination"
+					" MAC addresses are the same. Dropping "
+					"packet.\n",
+					dev_ll->dev->device_fh);
+					return;
+				}
+				offset = 4;
+				vlan_tag =
+				(uint16_t)
+				vlan_tags[(uint16_t)dev_ll->dev->device_fh];
+
+				LOG_DEBUG(VHOST_DATA,
+				"(%"PRIu64") TX: pkt to local VM device id:"
+				"(%"PRIu64") vlan tag: %d.\n",
+				dev->device_fh, dev_ll->dev->device_fh,
+				vlan_tag);
+
+				break;
+			}
+			dev_ll = dev_ll->next;
+		}
+	}
+
+	LOG_DEBUG(VHOST_DATA, "(%"PRIu64") TX: MAC address is external\n", dev->device_fh);
+
+	/*Add packet to the port tx queue*/
+	tx_q = &lcore_tx_queue[lcore_id];
+	len = tx_q->len;
+
+	/* Allocate an mbuf and populate the structure. */
+	mbuf = rte_pktmbuf_alloc(mbuf_pool);
+	if (unlikely(mbuf == NULL)) {
+		RTE_LOG(ERR, VHOST_DATA,
+			"Failed to allocate memory for mbuf.\n");
+		return;
+	}
+
+	mbuf->pkt.data_len = m->pkt.data_len + VLAN_HLEN + offset;
+	mbuf->pkt.pkt_len = m->pkt.pkt_len + VLAN_HLEN + offset;
+	mbuf->pkt.nb_segs = m->pkt.nb_segs;
+
+	/* Copy ethernet header to mbuf. */
+	rte_memcpy((void*)mbuf->pkt.data, (const void*)m->pkt.data, ETH_HLEN);
+
+
+	/* Setup vlan header. Bytes need to be re-ordered for network with htons()*/
+	vlan_hdr = (struct vlan_ethhdr *) mbuf->pkt.data;
+	vlan_hdr->h_vlan_encapsulated_proto = vlan_hdr->h_vlan_proto;
+	vlan_hdr->h_vlan_proto = htons(ETH_P_8021Q);
+	vlan_hdr->h_vlan_TCI = htons(vlan_tag);
+
+	/* Copy the remaining packet contents to the mbuf. */
+	rte_memcpy((void*) ((uint8_t*)mbuf->pkt.data + VLAN_ETH_HLEN),
+		(const void*) ((uint8_t*)m->pkt.data + ETH_HLEN), (m->pkt.data_len - ETH_HLEN));
+
+	/* Copy the remaining segments for the whole packet. */
+	prev = mbuf;
+	while (m->pkt.next) {
+		/* Allocate an mbuf and populate the structure. */
+		struct rte_mbuf *next_mbuf = rte_pktmbuf_alloc(mbuf_pool);
+		if (unlikely(next_mbuf == NULL)) {
+			rte_pktmbuf_free(mbuf);
+			RTE_LOG(ERR, VHOST_DATA,
+				"Failed to allocate memory for mbuf.\n");
+			return;
+		}
+
+		m = m->pkt.next;
+		prev->pkt.next = next_mbuf;
+		prev = next_mbuf;
+		next_mbuf->pkt.data_len = m->pkt.data_len;
+
+		/* Copy data to next mbuf. */
+		rte_memcpy(rte_pktmbuf_mtod(next_mbuf, void *),
+			rte_pktmbuf_mtod(m, const void *), m->pkt.data_len);
+	}
+
+	tx_q->m_table[len] = mbuf;
+	len++;
+	if (enable_stats) {
+		dev_statistics[dev->device_fh].tx_total++;
+		dev_statistics[dev->device_fh].tx++;
+	}
+
+	if (unlikely(len == MAX_PKT_BURST)) {
+		m_table = (struct rte_mbuf **)tx_q->m_table;
+		ret = rte_eth_tx_burst(ports[0], (uint16_t)tx_q->txq_id, m_table, (uint16_t) len);
+		/* Free any buffers not handled by TX and update the port stats. */
+		if (unlikely(ret < len)) {
+			do {
+				rte_pktmbuf_free(m_table[ret]);
+			} while (++ret < len);
+		}
+
+		len = 0;
+	}
+
+	tx_q->len = len;
+	return;
+}
+
+static inline void __attribute__((always_inline))
+virtio_dev_tx(struct virtio_net* dev, struct rte_mempool *mbuf_pool)
+{
+	struct rte_mbuf m;
+	struct vhost_virtqueue *vq;
+	struct vring_desc *desc;
+	uint64_t buff_addr = 0;
+	uint32_t head[MAX_PKT_BURST];
+	uint32_t used_idx;
+	uint32_t i;
+	uint16_t free_entries, packet_success = 0;
+	uint16_t avail_idx;
+
+	vq = dev->virtqueue[VIRTIO_TXQ];
+	avail_idx =  *((volatile uint16_t *)&vq->avail->idx);
+
+	/* If there are no available buffers then return. */
+	if (vq->last_used_idx == avail_idx)
+		return;
+
+	LOG_DEBUG(VHOST_DATA, "(%"PRIu64") virtio_dev_tx()\n", dev->device_fh);
+
+	/* Prefetch available ring to retrieve head indexes. */
+	rte_prefetch0(&vq->avail->ring[vq->last_used_idx & (vq->size - 1)]);
+
+	/*get the number of free entries in the ring*/
+	free_entries = (avail_idx - vq->last_used_idx);
+
+	/* Limit to MAX_PKT_BURST. */
+	if (free_entries > MAX_PKT_BURST)
+		free_entries = MAX_PKT_BURST;
+
+	LOG_DEBUG(VHOST_DATA, "(%"PRIu64") Buffers available %d\n", dev->device_fh, free_entries);
+	/* Retrieve all of the head indexes first to avoid caching issues. */
+	for (i = 0; i < free_entries; i++)
+		head[i] = vq->avail->ring[(vq->last_used_idx + i) & (vq->size - 1)];
+
+	/* Prefetch descriptor index. */
+	rte_prefetch0(&vq->desc[head[packet_success]]);
+	rte_prefetch0(&vq->used->ring[vq->last_used_idx & (vq->size - 1)]);
+
+	while (packet_success < free_entries) {
+		desc = &vq->desc[head[packet_success]];
+
+		/* Discard first buffer as it is the virtio header */
+		desc = &vq->desc[desc->next];
+
+		/* Buffer address translation. */
+		buff_addr = gpa_to_vva(dev, desc->addr);
+		/* Prefetch buffer address. */
+		rte_prefetch0((void*)(uintptr_t)buff_addr);
+
+		used_idx = vq->last_used_idx & (vq->size - 1);
+
+		if (packet_success < (free_entries - 1)) {
+			/* Prefetch descriptor index. */
+			rte_prefetch0(&vq->desc[head[packet_success+1]]);
+			rte_prefetch0(&vq->used->ring[(used_idx + 1) & (vq->size - 1)]);
+		}
+
+		/* Update used index buffer information. */
+		vq->used->ring[used_idx].id = head[packet_success];
+		vq->used->ring[used_idx].len = 0;
+
+		/* Setup dummy mbuf. This is copied to a real mbuf if transmitted out the physical port. */
+		m.pkt.data_len = desc->len;
+		m.pkt.pkt_len = desc->len;
+		m.pkt.data = (void*)(uintptr_t)buff_addr;
+
+		PRINT_PACKET(dev, (uintptr_t)buff_addr, desc->len, 0);
+
+		/* If this is the first received packet we need to learn the MAC and setup VMDQ */
+		if (dev->ready == DEVICE_MAC_LEARNING) {
+			if (dev->remove || (link_vmdq(dev, &m) == -1)) {
+				/*discard frame if device is scheduled for removal or a duplicate MAC address is found. */
+				packet_success += free_entries;
+				vq->last_used_idx += packet_success;
+				break;
+			}
+		}
+		virtio_tx_route(dev, &m, mbuf_pool, (uint16_t)dev->device_fh);
+
+		vq->last_used_idx++;
+		packet_success++;
+	}
+
+	rte_compiler_barrier();
+	vq->used->idx += packet_success;
+	/* Kick guest if required. */
+	if (!(vq->avail->flags & VRING_AVAIL_F_NO_INTERRUPT))
+		eventfd_write((int)vq->kickfd, 1);
+}
+
+/* This function works for TX packets with mergeable feature enabled. */
+static inline void __attribute__((always_inline))
+virtio_dev_merge_tx(struct virtio_net *dev, struct rte_mempool *mbuf_pool)
+{
+	struct rte_mbuf *m, *prev;
+	struct vhost_virtqueue *vq;
+	struct vring_desc *desc;
+	uint64_t vb_addr = 0;
+	uint32_t head[MAX_PKT_BURST];
+	uint32_t used_idx;
+	uint32_t i;
+	uint16_t free_entries, entry_success = 0;
+	uint16_t avail_idx;
+	uint32_t buf_size = MBUF_SIZE - (sizeof(struct rte_mbuf)
+			+ RTE_PKTMBUF_HEADROOM);
+
+	vq = dev->virtqueue[VIRTIO_TXQ];
+	avail_idx =  *((volatile uint16_t *)&vq->avail->idx);
+
+	/* If there are no available buffers then return. */
+	if (vq->last_used_idx == avail_idx)
+		return;
+
+	LOG_DEBUG(VHOST_DATA, "(%"PRIu64") virtio_dev_merge_tx()\n",
+		dev->device_fh);
+
+	/* Prefetch available ring to retrieve head indexes. */
+	rte_prefetch0(&vq->avail->ring[vq->last_used_idx & (vq->size - 1)]);
+
+	/*get the number of free entries in the ring*/
+	free_entries = (avail_idx - vq->last_used_idx);
+
+	/* Limit to MAX_PKT_BURST. */
+	free_entries = RTE_MIN(free_entries, MAX_PKT_BURST);
+
+	LOG_DEBUG(VHOST_DATA, "(%"PRIu64") Buffers available %d\n",
+		dev->device_fh, free_entries);
+	/* Retrieve all of the head indexes first to avoid caching issues. */
+	for (i = 0; i < free_entries; i++)
+		head[i] = vq->avail->ring[(vq->last_used_idx + i) & (vq->size - 1)];
+
+	/* Prefetch descriptor index. */
+	rte_prefetch0(&vq->desc[head[entry_success]]);
+	rte_prefetch0(&vq->used->ring[vq->last_used_idx & (vq->size - 1)]);
+
+	while (entry_success < free_entries) {
+		uint32_t vb_avail, vb_offset;
+		uint32_t seg_avail, seg_offset;
+		uint32_t cpy_len;
+		uint32_t seg_num = 0;
+		struct rte_mbuf *cur;
+		uint8_t alloc_err = 0;
+
+		desc = &vq->desc[head[entry_success]];
+
+		/* Discard first buffer as it is the virtio header */
+		desc = &vq->desc[desc->next];
+
+		/* Buffer address translation. */
+		vb_addr = gpa_to_vva(dev, desc->addr);
+		/* Prefetch buffer address. */
+		rte_prefetch0((void *)(uintptr_t)vb_addr);
+
+		used_idx = vq->last_used_idx & (vq->size - 1);
+
+		if (entry_success < (free_entries - 1)) {
+			/* Prefetch descriptor index. */
+			rte_prefetch0(&vq->desc[head[entry_success+1]]);
+			rte_prefetch0(&vq->used->ring[(used_idx + 1) & (vq->size - 1)]);
+		}
+
+		/* Update used index buffer information. */
+		vq->used->ring[used_idx].id = head[entry_success];
+		vq->used->ring[used_idx].len = 0;
+
+		vb_offset = 0;
+		vb_avail = desc->len;
+		seg_offset = 0;
+		seg_avail = buf_size;
+		cpy_len = RTE_MIN(vb_avail, seg_avail);
+
+		PRINT_PACKET(dev, (uintptr_t)vb_addr, desc->len, 0);
+
+		/* Allocate an mbuf and populate the structure. */
+		m = rte_pktmbuf_alloc(mbuf_pool);
+		if (unlikely(m == NULL)) {
+			RTE_LOG(ERR, VHOST_DATA,
+				"Failed to allocate memory for mbuf.\n");
+			return;
+		}
+
+		seg_num++;
+		cur = m;
+		prev = m;
+		while (cpy_len != 0) {
+			rte_memcpy((void *)(rte_pktmbuf_mtod(cur, char *) + seg_offset),
+				(void *)((uintptr_t)(vb_addr + vb_offset)),
+				cpy_len);
+
+			seg_offset += cpy_len;
+			vb_offset += cpy_len;
+			vb_avail -= cpy_len;
+			seg_avail -= cpy_len;
+
+			if (vb_avail != 0) {
+				/*
+				 * The segment reachs to its end,
+				 * while the virtio buffer in TX vring has
+				 * more data to be copied.
+				 */
+				cur->pkt.data_len = seg_offset;
+				m->pkt.pkt_len += seg_offset;
+				/* Allocate mbuf and populate the structure. */
+				cur = rte_pktmbuf_alloc(mbuf_pool);
+				if (unlikely(cur == NULL)) {
+					RTE_LOG(ERR, VHOST_DATA, "Failed to "
+						"allocate memory for mbuf.\n");
+					rte_pktmbuf_free(m);
+					alloc_err = 1;
+					break;
+				}
+
+				seg_num++;
+				prev->pkt.next = cur;
+				prev = cur;
+				seg_offset = 0;
+				seg_avail = buf_size;
+			} else {
+				if (desc->flags & VRING_DESC_F_NEXT) {
+					/*
+					 * There are more virtio buffers in
+					 * same vring entry need to be copied.
+					 */
+					if (seg_avail == 0) {
+						/*
+						 * The current segment hasn't
+						 * room to accomodate more
+						 * data.
+						 */
+						cur->pkt.data_len = seg_offset;
+						m->pkt.pkt_len += seg_offset;
+						/*
+						 * Allocate an mbuf and
+						 * populate the structure.
+						 */
+						cur = rte_pktmbuf_alloc(mbuf_pool);
+						if (unlikely(cur == NULL)) {
+							RTE_LOG(ERR,
+								VHOST_DATA,
+								"Failed to "
+								"allocate memory "
+								"for mbuf\n");
+							rte_pktmbuf_free(m);
+							alloc_err = 1;
+							break;
+						}
+						seg_num++;
+						prev->pkt.next = cur;
+						prev = cur;
+						seg_offset = 0;
+						seg_avail = buf_size;
+					}
+
+					desc = &vq->desc[desc->next];
+
+					/* Buffer address translation. */
+					vb_addr = gpa_to_vva(dev, desc->addr);
+					/* Prefetch buffer address. */
+					rte_prefetch0((void *)(uintptr_t)vb_addr);
+					vb_offset = 0;
+					vb_avail = desc->len;
+
+					PRINT_PACKET(dev, (uintptr_t)vb_addr,
+						desc->len, 0);
+				} else {
+					/* The whole packet completes. */
+					cur->pkt.data_len = seg_offset;
+					m->pkt.pkt_len += seg_offset;
+					vb_avail = 0;
+				}
+			}
+
+			cpy_len = RTE_MIN(vb_avail, seg_avail);
+		}
+
+		if (unlikely(alloc_err == 1))
+			break;
+
+		m->pkt.nb_segs = seg_num;
+
+		/*
+		 * If this is the first received packet we need to learn
+		 * the MAC and setup VMDQ
+		 */
+		if (dev->ready == DEVICE_MAC_LEARNING) {
+			if (dev->remove || (link_vmdq(dev, m) == -1)) {
+				/*
+				 * Discard frame if device is scheduled for
+				 * removal or a duplicate MAC address is found.
+				 */
+				entry_success = free_entries;
+				vq->last_used_idx += entry_success;
+				rte_pktmbuf_free(m);
+				break;
+			}
+		}
+
+		virtio_tx_route(dev, m, mbuf_pool, (uint16_t)dev->device_fh);
+		vq->last_used_idx++;
+		entry_success++;
+		rte_pktmbuf_free(m);
+	}
+
+	rte_compiler_barrier();
+	vq->used->idx += entry_success;
+	/* Kick guest if required. */
+	if (!(vq->avail->flags & VRING_AVAIL_F_NO_INTERRUPT))
+		eventfd_write((int)vq->kickfd, 1);
+
+}
+
+/*
+ * This function is called by each data core. It handles all RX/TX registered with the
+ * core. For TX the specific lcore linked list is used. For RX, MAC addresses are compared
+ * with all devices in the main linked list.
+ */
+static int
+switch_worker(__attribute__((unused)) void *arg)
+{
+	struct rte_mempool *mbuf_pool = arg;
+	struct virtio_net *dev = NULL;
+	struct rte_mbuf *pkts_burst[MAX_PKT_BURST];
+	struct virtio_net_data_ll *dev_ll;
+	struct mbuf_table *tx_q;
+	volatile struct lcore_ll_info *lcore_ll;
+	const uint64_t drain_tsc = (rte_get_tsc_hz() + US_PER_S - 1) / US_PER_S * BURST_TX_DRAIN_US;
+	uint64_t prev_tsc, diff_tsc, cur_tsc, ret_count = 0;
+	unsigned ret, i;
+	const uint16_t lcore_id = rte_lcore_id();
+	const uint16_t num_cores = (uint16_t)rte_lcore_count();
+	uint16_t rx_count = 0;
+	uint32_t mergeable = 0;
+
+	RTE_LOG(INFO, VHOST_DATA, "Procesing on Core %u started\n", lcore_id);
+	lcore_ll = lcore_info[lcore_id].lcore_ll;
+	prev_tsc = 0;
+
+	tx_q = &lcore_tx_queue[lcore_id];
+	for (i = 0; i < num_cores; i ++) {
+		if (lcore_ids[i] == lcore_id) {
+			tx_q->txq_id = i;
+			break;
+		}
+	}
+
+	while(1) {
+		cur_tsc = rte_rdtsc();
+		/*
+		 * TX burst queue drain
+		 */
+		diff_tsc = cur_tsc - prev_tsc;
+		if (unlikely(diff_tsc > drain_tsc)) {
+
+			if (tx_q->len) {
+				LOG_DEBUG(VHOST_DATA, "TX queue drained after timeout with burst size %u \n", tx_q->len);
+
+				/*Tx any packets in the queue*/
+				ret = rte_eth_tx_burst(ports[0], (uint16_t)tx_q->txq_id,
+									   (struct rte_mbuf **)tx_q->m_table,
+									   (uint16_t)tx_q->len);
+				if (unlikely(ret < tx_q->len)) {
+					do {
+						rte_pktmbuf_free(tx_q->m_table[ret]);
+					} while (++ret < tx_q->len);
+				}
+
+				tx_q->len = 0;
+			}
+
+			prev_tsc = cur_tsc;
+
+		}
+
+		rte_prefetch0(lcore_ll->ll_root_used);
+		/*
+		 * Inform the configuration core that we have exited the linked list and that no devices are
+		 * in use if requested.
+		 */
+		if (lcore_ll->dev_removal_flag == REQUEST_DEV_REMOVAL)
+			lcore_ll->dev_removal_flag = ACK_DEV_REMOVAL;
+
+		/*
+		 * Process devices
+		 */
+		dev_ll = lcore_ll->ll_root_used;
+
+		while (dev_ll != NULL) {
+			/*get virtio device ID*/
+			dev = dev_ll->dev;
+			mergeable =
+				dev->features & (1 << VIRTIO_NET_F_MRG_RXBUF);
+
+			if (dev->remove) {
+				dev_ll = dev_ll->next;
+				unlink_vmdq(dev);
+				dev->ready = DEVICE_SAFE_REMOVE;
+				continue;
+			}
+			if (likely(dev->ready == DEVICE_RX)) {
+				/*Handle guest RX*/
+				rx_count = rte_eth_rx_burst(ports[0],
+					(uint16_t)dev->vmdq_rx_q, pkts_burst, MAX_PKT_BURST);
+
+				if (rx_count) {
+					if (likely(mergeable == 0))
+						ret_count =
+							virtio_dev_rx(dev,
+							pkts_burst, rx_count);
+					else
+						ret_count =
+							virtio_dev_merge_rx(dev,
+							pkts_burst, rx_count);
+
+					if (enable_stats) {
+						rte_atomic64_add(
+						&dev_statistics[dev_ll->dev->device_fh].rx_total_atomic,
+						rx_count);
+						rte_atomic64_add(
+						&dev_statistics[dev_ll->dev->device_fh].rx_atomic, ret_count);
+					}
+					while (likely(rx_count)) {
+						rx_count--;
+						rte_pktmbuf_free(pkts_burst[rx_count]);
+					}
+
+				}
+			}
+
+			if (!dev->remove) {
+				/*Handle guest TX*/
+				if (likely(mergeable == 0))
+					virtio_dev_tx(dev, mbuf_pool);
+				else
+					virtio_dev_merge_tx(dev, mbuf_pool);
+			}
+
+			/*move to the next device in the list*/
+			dev_ll = dev_ll->next;
+		}
+	}
+
+	return 0;
+}
+
+/*
+ * This function gets available ring number for zero copy rx.
+ * Only one thread will call this funciton for a paticular virtio device,
+ * so, it is designed as non-thread-safe function.
+ */
+static inline uint32_t __attribute__((always_inline))
+get_available_ring_num_zcp(struct virtio_net *dev)
+{
+	struct vhost_virtqueue *vq = dev->virtqueue[VIRTIO_RXQ];
+	uint16_t avail_idx;
+
+	avail_idx = *((volatile uint16_t *)&vq->avail->idx);
+	return (uint32_t)(avail_idx - vq->last_used_idx_res);
+}
+
+/*
+ * This function gets available ring index for zero copy rx,
+ * it will retry 'burst_rx_retry_num' times till it get enough ring index.
+ * Only one thread will call this funciton for a paticular virtio device,
+ * so, it is designed as non-thread-safe function.
+ */
+static inline uint32_t __attribute__((always_inline))
+get_available_ring_index_zcp(struct virtio_net *dev,
+	uint16_t *res_base_idx, uint32_t count)
+{
+	struct vhost_virtqueue *vq = dev->virtqueue[VIRTIO_RXQ];
+	uint16_t avail_idx;
+	uint32_t retry = 0;
+	uint16_t free_entries;
+
+	*res_base_idx = vq->last_used_idx_res;
+	avail_idx = *((volatile uint16_t *)&vq->avail->idx);
+	free_entries = (avail_idx - *res_base_idx);
+
+	LOG_DEBUG(VHOST_DATA, "(%"PRIu64") in get_available_ring_index_zcp: "
+			"avail idx: %d, "
+			"res base idx:%d, free entries:%d\n",
+			dev->device_fh, avail_idx, *res_base_idx,
+			free_entries);
+
+	/*
+	 * If retry is enabled and the queue is full then we wait
+	 * and retry to avoid packet loss.
+	 */
+	if (enable_retry && unlikely(count > free_entries)) {
+		for (retry = 0; retry < burst_rx_retry_num; retry++) {
+			rte_delay_us(burst_rx_delay_time);
+			avail_idx = *((volatile uint16_t *)&vq->avail->idx);
+			free_entries = (avail_idx - *res_base_idx);
+			if (count <= free_entries)
+				break;
+		}
+	}
+
+	/*check that we have enough buffers*/
+	if (unlikely(count > free_entries))
+		count = free_entries;
+
+	if (unlikely(count == 0)) {
+		LOG_DEBUG(VHOST_DATA,
+			"(%"PRIu64") Fail in get_available_ring_index_zcp: "
+			"avail idx: %d, res base idx:%d, free entries:%d\n",
+			dev->device_fh, avail_idx,
+			*res_base_idx, free_entries);
+		return 0;
+	}
+
+	vq->last_used_idx_res = *res_base_idx + count;
+
+	return count;
+}
+
+/*
+ * This function put descriptor back to used list.
+ */
+static inline void __attribute__((always_inline))
+put_desc_to_used_list_zcp(struct vhost_virtqueue *vq, uint16_t desc_idx)
+{
+	uint16_t res_cur_idx = vq->last_used_idx;
+	vq->used->ring[res_cur_idx & (vq->size - 1)].id = (uint32_t)desc_idx;
+	vq->used->ring[res_cur_idx & (vq->size - 1)].len = 0;
+	rte_compiler_barrier();
+	*(volatile uint16_t *)&vq->used->idx += 1;
+	vq->last_used_idx += 1;
+
+	/* Kick the guest if necessary. */
+	if (!(vq->avail->flags & VRING_AVAIL_F_NO_INTERRUPT))
+		eventfd_write((int)vq->kickfd, 1);
+}
+
+/*
+ * This function get available descriptor from vitio vring and un-attached mbuf
+ * from vpool->ring, and then attach them together. It needs adjust the offset
+ * for buff_addr and phys_addr accroding to PMD implementation, otherwise the
+ * frame data may be put to wrong location in mbuf.
+ */
+static inline void __attribute__((always_inline))
+attach_rxmbuf_zcp(struct virtio_net *dev)
+{
+	uint16_t res_base_idx, desc_idx;
+	uint64_t buff_addr, phys_addr;
+	struct vhost_virtqueue *vq;
+	struct vring_desc *desc;
+	struct rte_mbuf *mbuf = NULL;
+	struct vpool *vpool;
+	hpa_type addr_type;
+
+	vpool = &vpool_array[dev->vmdq_rx_q];
+	vq = dev->virtqueue[VIRTIO_RXQ];
+
+	do {
+		if (unlikely(get_available_ring_index_zcp(dev, &res_base_idx,
+				1) != 1))
+			return;
+		desc_idx = vq->avail->ring[(res_base_idx) & (vq->size - 1)];
+
+		desc = &vq->desc[desc_idx];
+		if (desc->flags & VRING_DESC_F_NEXT) {
+			desc = &vq->desc[desc->next];
+			buff_addr = gpa_to_vva(dev, desc->addr);
+			phys_addr = gpa_to_hpa(dev, desc->addr, desc->len,
+					&addr_type);
+		} else {
+			buff_addr = gpa_to_vva(dev,
+					desc->addr + vq->vhost_hlen);
+			phys_addr = gpa_to_hpa(dev,
+					desc->addr + vq->vhost_hlen,
+					desc->len, &addr_type);
+		}
+
+		if (unlikely(addr_type == PHYS_ADDR_INVALID)) {
+			RTE_LOG(ERR, VHOST_DATA, "(%"PRIu64") Invalid frame buffer"
+				" address found when attaching RX frame buffer"
+				" address!\n", dev->device_fh);
+			put_desc_to_used_list_zcp(vq, desc_idx);
+			continue;
+		}
+
+		/*
+		 * Check if the frame buffer address from guest crosses
+		 * sub-region or not.
+		 */
+		if (unlikely(addr_type == PHYS_ADDR_CROSS_SUBREG)) {
+			RTE_LOG(ERR, VHOST_DATA,
+				"(%"PRIu64") Frame buffer address cross "
+				"sub-regioin found when attaching RX frame "
+				"buffer address!\n",
+				dev->device_fh);
+			put_desc_to_used_list_zcp(vq, desc_idx);
+			continue;
+		}
+	} while (unlikely(phys_addr == 0));
+
+	rte_ring_sc_dequeue(vpool->ring, (void **)&mbuf);
+	if (unlikely(mbuf == NULL)) {
+		LOG_DEBUG(VHOST_DATA,
+			"(%"PRIu64") in attach_rxmbuf_zcp: "
+			"ring_sc_dequeue fail.\n",
+			dev->device_fh);
+		put_desc_to_used_list_zcp(vq, desc_idx);
+		return;
+	}
+
+	if (unlikely(vpool->buf_size > desc->len)) {
+		LOG_DEBUG(VHOST_DATA,
+			"(%"PRIu64") in attach_rxmbuf_zcp: frame buffer "
+			"length(%d) of descriptor idx: %d less than room "
+			"size required: %d\n",
+			dev->device_fh, desc->len, desc_idx, vpool->buf_size);
+		put_desc_to_used_list_zcp(vq, desc_idx);
+		rte_ring_sp_enqueue(vpool->ring, (void *)mbuf);
+		return;
+	}
+
+	mbuf->buf_addr = (void *)(uintptr_t)(buff_addr - RTE_PKTMBUF_HEADROOM);
+	mbuf->pkt.data = (void *)(uintptr_t)(buff_addr);
+	mbuf->buf_physaddr = phys_addr - RTE_PKTMBUF_HEADROOM;
+	mbuf->pkt.data_len = desc->len;
+	MBUF_HEADROOM_UINT32(mbuf) = (uint32_t)desc_idx;
+
+	LOG_DEBUG(VHOST_DATA,
+		"(%"PRIu64") in attach_rxmbuf_zcp: res base idx:%d, "
+		"descriptor idx:%d\n",
+		dev->device_fh, res_base_idx, desc_idx);
+
+	__rte_mbuf_raw_free(mbuf);
+
+	return;
+}
+
+/*
+ * Detach an attched packet mbuf -
+ *  - restore original mbuf address and length values.
+ *  - reset pktmbuf data and data_len to their default values.
+ *  All other fields of the given packet mbuf will be left intact.
+ *
+ * @param m
+ *   The attached packet mbuf.
+ */
+static inline void pktmbuf_detach_zcp(struct rte_mbuf *m)
+{
+	const struct rte_mempool *mp = m->pool;
+	void *buf = RTE_MBUF_TO_BADDR(m);
+	uint32_t buf_ofs;
+	uint32_t buf_len = mp->elt_size - sizeof(*m);
+	m->buf_physaddr = rte_mempool_virt2phy(mp, m) + sizeof(*m);
+
+	m->buf_addr = buf;
+	m->buf_len = (uint16_t)buf_len;
+
+	buf_ofs = (RTE_PKTMBUF_HEADROOM <= m->buf_len) ?
+			RTE_PKTMBUF_HEADROOM : m->buf_len;
+	m->pkt.data = (char *) m->buf_addr + buf_ofs;
+
+	m->pkt.data_len = 0;
+}
+
+/*
+ * This function is called after packets have been transimited. It fetchs mbuf
+ * from vpool->pool, detached it and put into vpool->ring. It also update the
+ * used index and kick the guest if necessary.
+ */
+static inline uint32_t __attribute__((always_inline))
+txmbuf_clean_zcp(struct virtio_net *dev, struct vpool *vpool)
+{
+	struct rte_mbuf *mbuf;
+	struct vhost_virtqueue *vq = dev->virtqueue[VIRTIO_TXQ];
+	uint32_t used_idx = vq->last_used_idx & (vq->size - 1);
+	uint32_t index = 0;
+	uint32_t mbuf_count = rte_mempool_count(vpool->pool);
+
+	LOG_DEBUG(VHOST_DATA,
+		"(%"PRIu64") in txmbuf_clean_zcp: mbuf count in mempool before "
+		"clean is: %d\n",
+		dev->device_fh, mbuf_count);
+	LOG_DEBUG(VHOST_DATA,
+		"(%"PRIu64") in txmbuf_clean_zcp: mbuf count in  ring before "
+		"clean  is : %d\n",
+		dev->device_fh, rte_ring_count(vpool->ring));
+
+	for (index = 0; index < mbuf_count; index++) {
+		mbuf = __rte_mbuf_raw_alloc(vpool->pool);
+		if (likely(RTE_MBUF_INDIRECT(mbuf)))
+			pktmbuf_detach_zcp(mbuf);
+		rte_ring_sp_enqueue(vpool->ring, mbuf);
+
+		/* Update used index buffer information. */
+		vq->used->ring[used_idx].id = MBUF_HEADROOM_UINT32(mbuf);
+		vq->used->ring[used_idx].len = 0;
+
+		used_idx = (used_idx + 1) & (vq->size - 1);
+	}
+
+	LOG_DEBUG(VHOST_DATA,
+		"(%"PRIu64") in txmbuf_clean_zcp: mbuf count in mempool after "
+		"clean is: %d\n",
+		dev->device_fh, rte_mempool_count(vpool->pool));
+	LOG_DEBUG(VHOST_DATA,
+		"(%"PRIu64") in txmbuf_clean_zcp: mbuf count in  ring after "
+		"clean  is : %d\n",
+		dev->device_fh, rte_ring_count(vpool->ring));
+	LOG_DEBUG(VHOST_DATA,
+		"(%"PRIu64") in txmbuf_clean_zcp: before updated "
+		"vq->last_used_idx:%d\n",
+		dev->device_fh, vq->last_used_idx);
+
+	vq->last_used_idx += mbuf_count;
+
+	LOG_DEBUG(VHOST_DATA,
+		"(%"PRIu64") in txmbuf_clean_zcp: after updated "
+		"vq->last_used_idx:%d\n",
+		dev->device_fh, vq->last_used_idx);
+
+	rte_compiler_barrier();
+
+	*(volatile uint16_t *)&vq->used->idx += mbuf_count;
+
+	/* Kick guest if required. */
+	if (!(vq->avail->flags & VRING_AVAIL_F_NO_INTERRUPT))
+		eventfd_write((int)vq->kickfd, 1);
+
+	return 0;
+}
+
+/*
+ * This function is called when a virtio device is destroy.
+ * It fetchs mbuf from vpool->pool, and detached it, and put into vpool->ring.
+ */
+static void mbuf_destroy_zcp(struct vpool *vpool)
+{
+	struct rte_mbuf *mbuf = NULL;
+	uint32_t index, mbuf_count = rte_mempool_count(vpool->pool);
+
+	LOG_DEBUG(VHOST_CONFIG,
+		"in mbuf_destroy_zcp: mbuf count in mempool before "
+		"mbuf_destroy_zcp is: %d\n",
+		mbuf_count);
+	LOG_DEBUG(VHOST_CONFIG,
+		"in mbuf_destroy_zcp: mbuf count in  ring before "
+		"mbuf_destroy_zcp  is : %d\n",
+		rte_ring_count(vpool->ring));
+
+	for (index = 0; index < mbuf_count; index++) {
+		mbuf = __rte_mbuf_raw_alloc(vpool->pool);
+		if (likely(mbuf != NULL)) {
+			if (likely(RTE_MBUF_INDIRECT(mbuf)))
+				pktmbuf_detach_zcp(mbuf);
+			rte_ring_sp_enqueue(vpool->ring, (void *)mbuf);
+		}
+	}
+
+	LOG_DEBUG(VHOST_CONFIG,
+		"in mbuf_destroy_zcp: mbuf count in mempool after "
+		"mbuf_destroy_zcp is: %d\n",
+		rte_mempool_count(vpool->pool));
+	LOG_DEBUG(VHOST_CONFIG,
+		"in mbuf_destroy_zcp: mbuf count in ring after "
+		"mbuf_destroy_zcp is : %d\n",
+		rte_ring_count(vpool->ring));
+}
+
+/*
+ * This function update the use flag and counter.
+ */
+static inline uint32_t __attribute__((always_inline))
+virtio_dev_rx_zcp(struct virtio_net *dev, struct rte_mbuf **pkts,
+	uint32_t count)
+{
+	struct vhost_virtqueue *vq;
+	struct vring_desc *desc;
+	struct rte_mbuf *buff;
+	/* The virtio_hdr is initialised to 0. */
+	struct virtio_net_hdr_mrg_rxbuf virtio_hdr
+		= {{0, 0, 0, 0, 0, 0}, 0};
+	uint64_t buff_hdr_addr = 0;
+	uint32_t head[MAX_PKT_BURST], packet_len = 0;
+	uint32_t head_idx, packet_success = 0;
+	uint16_t res_cur_idx;
+
+	LOG_DEBUG(VHOST_DATA, "(%"PRIu64") virtio_dev_rx()\n", dev->device_fh);
+
+	if (count == 0)
+		return 0;
+
+	vq = dev->virtqueue[VIRTIO_RXQ];
+	count = (count > MAX_PKT_BURST) ? MAX_PKT_BURST : count;
+
+	res_cur_idx = vq->last_used_idx;
+	LOG_DEBUG(VHOST_DATA, "(%"PRIu64") Current Index %d| End Index %d\n",
+		dev->device_fh, res_cur_idx, res_cur_idx + count);
+
+	/* Retrieve all of the head indexes first to avoid caching issues. */
+	for (head_idx = 0; head_idx < count; head_idx++)
+		head[head_idx] = MBUF_HEADROOM_UINT32(pkts[head_idx]);
+
+	/*Prefetch descriptor index. */
+	rte_prefetch0(&vq->desc[head[packet_success]]);
+
+	while (packet_success != count) {
+		/* Get descriptor from available ring */
+		desc = &vq->desc[head[packet_success]];
+
+		buff = pkts[packet_success];
+		LOG_DEBUG(VHOST_DATA,
+			"(%"PRIu64") in dev_rx_zcp: update the used idx for "
+			"pkt[%d] descriptor idx: %d\n",
+			dev->device_fh, packet_success,
+			MBUF_HEADROOM_UINT32(buff));
+
+		PRINT_PACKET(dev,
+			(uintptr_t)(((uint64_t)(uintptr_t)buff->buf_addr)
+			+ RTE_PKTMBUF_HEADROOM),
+			rte_pktmbuf_data_len(buff), 0);
+
+		/* Buffer address translation for virtio header. */
+		buff_hdr_addr = gpa_to_vva(dev, desc->addr);
+		packet_len = rte_pktmbuf_data_len(buff) + vq->vhost_hlen;
+
+		/*
+		 * If the descriptors are chained the header and data are
+		 * placed in separate buffers.
+		 */
+		if (desc->flags & VRING_DESC_F_NEXT) {
+			desc->len = vq->vhost_hlen;
+			desc = &vq->desc[desc->next];
+			desc->len = rte_pktmbuf_data_len(buff);
+		} else {
+			desc->len = packet_len;
+		}
+
+		/* Update used ring with desc information */
+		vq->used->ring[res_cur_idx & (vq->size - 1)].id
+			= head[packet_success];
+		vq->used->ring[res_cur_idx & (vq->size - 1)].len
+			= packet_len;
+		res_cur_idx++;
+		packet_success++;
+
+		/* A header is required per buffer. */
+		rte_memcpy((void *)(uintptr_t)buff_hdr_addr,
+			(const void *)&virtio_hdr, vq->vhost_hlen);
+
+		PRINT_PACKET(dev, (uintptr_t)buff_hdr_addr, vq->vhost_hlen, 1);
+
+		if (likely(packet_success < count)) {
+			/* Prefetch descriptor index. */
+			rte_prefetch0(&vq->desc[head[packet_success]]);
+		}
+	}
+
+	rte_compiler_barrier();
+
+	LOG_DEBUG(VHOST_DATA,
+		"(%"PRIu64") in dev_rx_zcp: before update used idx: "
+		"vq.last_used_idx: %d, vq->used->idx: %d\n",
+		dev->device_fh, vq->last_used_idx, vq->used->idx);
+
+	*(volatile uint16_t *)&vq->used->idx += count;
+	vq->last_used_idx += count;
+
+	LOG_DEBUG(VHOST_DATA,
+		"(%"PRIu64") in dev_rx_zcp: after  update used idx: "
+		"vq.last_used_idx: %d, vq->used->idx: %d\n",
+		dev->device_fh, vq->last_used_idx, vq->used->idx);
+
+	/* Kick the guest if necessary. */
+	if (!(vq->avail->flags & VRING_AVAIL_F_NO_INTERRUPT))
+		eventfd_write((int)vq->kickfd, 1);
+
+	return count;
+}
+
+/*
+ * This function routes the TX packet to the correct interface.
+ * This may be a local device or the physical port.
+ */
+static inline void __attribute__((always_inline))
+virtio_tx_route_zcp(struct virtio_net *dev, struct rte_mbuf *m,
+	uint32_t desc_idx, uint8_t need_copy)
+{
+	struct mbuf_table *tx_q;
+	struct rte_mbuf **m_table;
+	struct rte_mbuf *mbuf = NULL;
+	unsigned len, ret, offset = 0;
+	struct vpool *vpool;
+	struct virtio_net_data_ll *dev_ll = ll_root_used;
+	struct ether_hdr *pkt_hdr = (struct ether_hdr *)m->pkt.data;
+	uint16_t vlan_tag = (uint16_t)vlan_tags[(uint16_t)dev->device_fh];
+
+	/*Add packet to the port tx queue*/
+	tx_q = &tx_queue_zcp[(uint16_t)dev->vmdq_rx_q];
+	len = tx_q->len;
+
+	/* Allocate an mbuf and populate the structure. */
+	vpool = &vpool_array[MAX_QUEUES + (uint16_t)dev->vmdq_rx_q];
+	rte_ring_sc_dequeue(vpool->ring, (void **)&mbuf);
+	if (unlikely(mbuf == NULL)) {
+		struct vhost_virtqueue *vq = dev->virtqueue[VIRTIO_TXQ];
+		RTE_LOG(ERR, VHOST_DATA,
+			"(%"PRIu64") Failed to allocate memory for mbuf.\n",
+			dev->device_fh);
+		put_desc_to_used_list_zcp(vq, desc_idx);
+		return;
+	}
+
+	if (vm2vm_mode == VM2VM_HARDWARE) {
+		/* Avoid using a vlan tag from any vm for external pkt, such as
+		 * vlan_tags[dev->device_fh], oterwise, it conflicts when pool
+		 * selection, MAC address determines it as an external pkt
+		 * which should go to network, while vlan tag determine it as
+		 * a vm2vm pkt should forward to another vm. Hardware confuse
+		 * such a ambiguous situation, so pkt will lost.
+		 */
+		vlan_tag = external_pkt_default_vlan_tag;
+		while (dev_ll != NULL) {
+			if (likely(dev_ll->dev->ready == DEVICE_RX) &&
+				ether_addr_cmp(&(pkt_hdr->d_addr),
+				&dev_ll->dev->mac_address)) {
+
+				/*
+				 * Drop the packet if the TX packet is destined
+				 * for the TX device.
+				 */
+				if (unlikely(dev_ll->dev->device_fh
+					== dev->device_fh)) {
+					LOG_DEBUG(VHOST_DATA,
+					"(%"PRIu64") TX: Source and destination"
+					"MAC addresses are the same. Dropping "
+					"packet.\n",
+					dev_ll->dev->device_fh);
+					MBUF_HEADROOM_UINT32(mbuf)
+						= (uint32_t)desc_idx;
+					__rte_mbuf_raw_free(mbuf);
+					return;
+				}
+
+				/*
+				 * Packet length offset 4 bytes for HW vlan
+				 * strip when L2 switch back.
+				 */
+				offset = 4;
+				vlan_tag =
+				(uint16_t)
+				vlan_tags[(uint16_t)dev_ll->dev->device_fh];
+
+				LOG_DEBUG(VHOST_DATA,
+				"(%"PRIu64") TX: pkt to local VM device id:"
+				"(%"PRIu64") vlan tag: %d.\n",
+				dev->device_fh, dev_ll->dev->device_fh,
+				vlan_tag);
+
+				break;
+			}
+			dev_ll = dev_ll->next;
+		}
+	}
+
+	mbuf->pkt.nb_segs = m->pkt.nb_segs;
+	mbuf->pkt.next = m->pkt.next;
+	mbuf->pkt.data_len = m->pkt.data_len + offset;
+	mbuf->pkt.pkt_len = mbuf->pkt.data_len;
+	if (unlikely(need_copy)) {
+		/* Copy the packet contents to the mbuf. */
+		rte_memcpy((void *)((uint8_t *)mbuf->pkt.data),
+			(const void *) ((uint8_t *)m->pkt.data),
+			m->pkt.data_len);
+	} else {
+		mbuf->pkt.data = m->pkt.data;
+		mbuf->buf_physaddr = m->buf_physaddr;
+		mbuf->buf_addr = m->buf_addr;
+	}
+	mbuf->ol_flags = PKT_TX_VLAN_PKT;
+	mbuf->pkt.vlan_macip.f.vlan_tci = vlan_tag;
+	mbuf->pkt.vlan_macip.f.l2_len = sizeof(struct ether_hdr);
+	mbuf->pkt.vlan_macip.f.l3_len = sizeof(struct ipv4_hdr);
+	MBUF_HEADROOM_UINT32(mbuf) = (uint32_t)desc_idx;
+
+	tx_q->m_table[len] = mbuf;
+	len++;
+
+	LOG_DEBUG(VHOST_DATA,
+		"(%"PRIu64") in tx_route_zcp: pkt: nb_seg: %d, next:%s\n",
+		dev->device_fh,
+		mbuf->pkt.nb_segs,
+		(mbuf->pkt.next == NULL) ? "null" : "non-null");
+
+	if (enable_stats) {
+		dev_statistics[dev->device_fh].tx_total++;
+		dev_statistics[dev->device_fh].tx++;
+	}
+
+	if (unlikely(len == MAX_PKT_BURST)) {
+		m_table = (struct rte_mbuf **)tx_q->m_table;
+		ret = rte_eth_tx_burst(ports[0],
+			(uint16_t)tx_q->txq_id, m_table, (uint16_t) len);
+
+		/*
+		 * Free any buffers not handled by TX and update
+		 * the port stats.
+		 */
+		if (unlikely(ret < len)) {
+			do {
+				rte_pktmbuf_free(m_table[ret]);
+			} while (++ret < len);
+		}
+
+		len = 0;
+		txmbuf_clean_zcp(dev, vpool);
+	}
+
+	tx_q->len = len;
+
+	return;
+}
+
+/*
+ * This function TX all available packets in virtio TX queue for one
+ * virtio-net device. If it is first packet, it learns MAC address and
+ * setup VMDQ.
+ */
+static inline void __attribute__((always_inline))
+virtio_dev_tx_zcp(struct virtio_net *dev)
+{
+	struct rte_mbuf m;
+	struct vhost_virtqueue *vq;
+	struct vring_desc *desc;
+	uint64_t buff_addr = 0, phys_addr;
+	uint32_t head[MAX_PKT_BURST];
+	uint32_t i;
+	uint16_t free_entries, packet_success = 0;
+	uint16_t avail_idx;
+	uint8_t need_copy = 0;
+	hpa_type addr_type;
+
+	vq = dev->virtqueue[VIRTIO_TXQ];
+	avail_idx =  *((volatile uint16_t *)&vq->avail->idx);
+
+	/* If there are no available buffers then return. */
+	if (vq->last_used_idx_res == avail_idx)
+		return;
+
+	LOG_DEBUG(VHOST_DATA, "(%"PRIu64") virtio_dev_tx()\n", dev->device_fh);
+
+	/* Prefetch available ring to retrieve head indexes. */
+	rte_prefetch0(&vq->avail->ring[vq->last_used_idx_res & (vq->size - 1)]);
+
+	/* Get the number of free entries in the ring */
+	free_entries = (avail_idx - vq->last_used_idx_res);
+
+	/* Limit to MAX_PKT_BURST. */
+	free_entries
+		= (free_entries > MAX_PKT_BURST) ? MAX_PKT_BURST : free_entries;
+
+	LOG_DEBUG(VHOST_DATA, "(%"PRIu64") Buffers available %d\n",
+		dev->device_fh, free_entries);
+
+	/* Retrieve all of the head indexes first to avoid caching issues. */
+	for (i = 0; i < free_entries; i++)
+		head[i]
+			= vq->avail->ring[(vq->last_used_idx_res + i)
+			& (vq->size - 1)];
+
+	vq->last_used_idx_res += free_entries;
+
+	/* Prefetch descriptor index. */
+	rte_prefetch0(&vq->desc[head[packet_success]]);
+	rte_prefetch0(&vq->used->ring[vq->last_used_idx & (vq->size - 1)]);
+
+	while (packet_success < free_entries) {
+		desc = &vq->desc[head[packet_success]];
+
+		/* Discard first buffer as it is the virtio header */
+		desc = &vq->desc[desc->next];
+
+		/* Buffer address translation. */
+		buff_addr = gpa_to_vva(dev, desc->addr);
+		phys_addr = gpa_to_hpa(dev, desc->addr, desc->len, &addr_type);
+
+		if (likely(packet_success < (free_entries - 1)))
+			/* Prefetch descriptor index. */
+			rte_prefetch0(&vq->desc[head[packet_success + 1]]);
+
+		if (unlikely(addr_type == PHYS_ADDR_INVALID)) {
+			RTE_LOG(ERR, VHOST_DATA,
+				"(%"PRIu64") Invalid frame buffer address found"
+				"when TX packets!\n",
+				dev->device_fh);
+			packet_success++;
+			continue;
+		}
+
+		/* Prefetch buffer address. */
+		rte_prefetch0((void *)(uintptr_t)buff_addr);
+
+		/*
+		 * Setup dummy mbuf. This is copied to a real mbuf if
+		 * transmitted out the physical port.
+		 */
+		m.pkt.data_len = desc->len;
+		m.pkt.nb_segs = 1;
+		m.pkt.next = NULL;
+		m.pkt.data = (void *)(uintptr_t)buff_addr;
+		m.buf_addr = m.pkt.data;
+		m.buf_physaddr = phys_addr;
+
+		/*
+		 * Check if the frame buffer address from guest crosses
+		 * sub-region or not.
+		 */
+		if (unlikely(addr_type == PHYS_ADDR_CROSS_SUBREG)) {
+			RTE_LOG(ERR, VHOST_DATA,
+				"(%"PRIu64") Frame buffer address cross "
+				"sub-regioin found when attaching TX frame "
+				"buffer address!\n",
+				dev->device_fh);
+			need_copy = 1;
+		} else
+			need_copy = 0;
+
+		PRINT_PACKET(dev, (uintptr_t)buff_addr, desc->len, 0);
+
+		/*
+		 * If this is the first received packet we need to learn
+		 * the MAC and setup VMDQ
+		 */
+		if (unlikely(dev->ready == DEVICE_MAC_LEARNING)) {
+			if (dev->remove || (link_vmdq(dev, &m) == -1)) {
+				/*
+				 * Discard frame if device is scheduled for
+				 * removal or a duplicate MAC address is found.
+				 */
+				packet_success += free_entries;
+				vq->last_used_idx += packet_success;
+				break;
+			}
+		}
+
+		virtio_tx_route_zcp(dev, &m, head[packet_success], need_copy);
+		packet_success++;
+	}
+}
+
+/*
+ * This function is called by each data core. It handles all RX/TX registered
+ * with the core. For TX the specific lcore linked list is used. For RX, MAC
+ * addresses are compared with all devices in the main linked list.
+ */
+static int
+switch_worker_zcp(__attribute__((unused)) void *arg)
+{
+	struct virtio_net *dev = NULL;
+	struct rte_mbuf *pkts_burst[MAX_PKT_BURST];
+	struct virtio_net_data_ll *dev_ll;
+	struct mbuf_table *tx_q;
+	volatile struct lcore_ll_info *lcore_ll;
+	const uint64_t drain_tsc
+		= (rte_get_tsc_hz() + US_PER_S - 1) / US_PER_S
+		* BURST_TX_DRAIN_US;
+	uint64_t prev_tsc, diff_tsc, cur_tsc, ret_count = 0;
+	unsigned ret;
+	const uint16_t lcore_id = rte_lcore_id();
+	uint16_t count_in_ring, rx_count = 0;
+
+	RTE_LOG(INFO, VHOST_DATA, "Procesing on Core %u started\n", lcore_id);
+
+	lcore_ll = lcore_info[lcore_id].lcore_ll;
+	prev_tsc = 0;
+
+	while (1) {
+		cur_tsc = rte_rdtsc();
+
+		/* TX burst queue drain */
+		diff_tsc = cur_tsc - prev_tsc;
+		if (unlikely(diff_tsc > drain_tsc)) {
+			/*
+			 * Get mbuf from vpool.pool and detach mbuf and
+			 * put back into vpool.ring.
+			 */
+			dev_ll = lcore_ll->ll_root_used;
+			while ((dev_ll != NULL) && (dev_ll->dev != NULL)) {
+				/* Get virtio device ID */
+				dev = dev_ll->dev;
+
+				if (likely(!dev->remove)) {
+					tx_q = &tx_queue_zcp[(uint16_t)dev->vmdq_rx_q];
+					if (tx_q->len) {
+						LOG_DEBUG(VHOST_DATA,
+						"TX queue drained after timeout"
+						" with burst size %u\n",
+						tx_q->len);
+
+						/*
+						 * Tx any packets in the queue
+						 */
+						ret = rte_eth_tx_burst(
+							ports[0],
+							(uint16_t)tx_q->txq_id,
+							(struct rte_mbuf **)
+							tx_q->m_table,
+							(uint16_t)tx_q->len);
+						if (unlikely(ret < tx_q->len)) {
+							do {
+								rte_pktmbuf_free(
+									tx_q->m_table[ret]);
+							} while (++ret < tx_q->len);
+						}
+						tx_q->len = 0;
+
+						txmbuf_clean_zcp(dev,
+							&vpool_array[MAX_QUEUES+dev->vmdq_rx_q]);
+					}
+				}
+				dev_ll = dev_ll->next;
+			}
+			prev_tsc = cur_tsc;
+		}
+
+		rte_prefetch0(lcore_ll->ll_root_used);
+
+		/*
+		 * Inform the configuration core that we have exited the linked
+		 * list and that no devices are in use if requested.
+		 */
+		if (lcore_ll->dev_removal_flag == REQUEST_DEV_REMOVAL)
+			lcore_ll->dev_removal_flag = ACK_DEV_REMOVAL;
+
+		/* Process devices */
+		dev_ll = lcore_ll->ll_root_used;
+
+		while ((dev_ll != NULL) && (dev_ll->dev != NULL)) {
+			dev = dev_ll->dev;
+			if (unlikely(dev->remove)) {
+				dev_ll = dev_ll->next;
+				unlink_vmdq(dev);
+				dev->ready = DEVICE_SAFE_REMOVE;
+				continue;
+			}
+
+			if (likely(dev->ready == DEVICE_RX)) {
+				uint32_t index = dev->vmdq_rx_q;
+				uint16_t i;
+				count_in_ring
+				= rte_ring_count(vpool_array[index].ring);
+				uint16_t free_entries
+				= (uint16_t)get_available_ring_num_zcp(dev);
+
+				/*
+				 * Attach all mbufs in vpool.ring and put back
+				 * into vpool.pool.
+				 */
+				for (i = 0;
+				i < RTE_MIN(free_entries,
+				RTE_MIN(count_in_ring, MAX_PKT_BURST));
+				i++)
+					attach_rxmbuf_zcp(dev);
+
+				/* Handle guest RX */
+				rx_count = rte_eth_rx_burst(ports[0],
+					(uint16_t)dev->vmdq_rx_q, pkts_burst,
+					MAX_PKT_BURST);
+
+				if (rx_count) {
+					ret_count = virtio_dev_rx_zcp(dev,
+							pkts_burst, rx_count);
+					if (enable_stats) {
+						dev_statistics[dev->device_fh].rx_total
+							+= rx_count;
+						dev_statistics[dev->device_fh].rx
+							+= ret_count;
+					}
+					while (likely(rx_count)) {
+						rx_count--;
+						pktmbuf_detach_zcp(
+							pkts_burst[rx_count]);
+						rte_ring_sp_enqueue(
+							vpool_array[index].ring,
+							(void *)pkts_burst[rx_count]);
+					}
+				}
+			}
+
+			if (likely(!dev->remove))
+				/* Handle guest TX */
+				virtio_dev_tx_zcp(dev);
+
+			/* Move to the next device in the list */
+			dev_ll = dev_ll->next;
+		}
+	}
+
+	return 0;
+}
+
+
+/*
+ * Add an entry to a used linked list. A free entry must first be found
+ * in the free linked list using get_data_ll_free_entry();
+ */
+static void
+add_data_ll_entry(struct virtio_net_data_ll **ll_root_addr,
+	struct virtio_net_data_ll *ll_dev)
+{
+	struct virtio_net_data_ll *ll = *ll_root_addr;
+
+	/* Set next as NULL and use a compiler barrier to avoid reordering. */
+	ll_dev->next = NULL;
+	rte_compiler_barrier();
+
+	/* If ll == NULL then this is the first device. */
+	if (ll) {
+		/* Increment to the tail of the linked list. */
+		while ((ll->next != NULL) )
+			ll = ll->next;
+
+		ll->next = ll_dev;
+	} else {
+		*ll_root_addr = ll_dev;
+	}
+}
+
+/*
+ * Remove an entry from a used linked list. The entry must then be added to
+ * the free linked list using put_data_ll_free_entry().
+ */
+static void
+rm_data_ll_entry(struct virtio_net_data_ll **ll_root_addr,
+	struct virtio_net_data_ll *ll_dev,
+	struct virtio_net_data_ll *ll_dev_last)
+{
+	struct virtio_net_data_ll *ll = *ll_root_addr;
+
+	if (unlikely((ll == NULL) || (ll_dev == NULL)))
+		return;
+
+	if (ll_dev == ll)
+		*ll_root_addr = ll_dev->next;
+	else
+		if (likely(ll_dev_last != NULL))
+			ll_dev_last->next = ll_dev->next;
+		else
+			RTE_LOG(ERR, VHOST_CONFIG, "Remove entry form ll failed.\n");
+}
+
+/*
+ * Find and return an entry from the free linked list.
+ */
+static struct virtio_net_data_ll *
+get_data_ll_free_entry(struct virtio_net_data_ll **ll_root_addr)
+{
+	struct virtio_net_data_ll *ll_free = *ll_root_addr;
+	struct virtio_net_data_ll *ll_dev;
+
+	if (ll_free == NULL)
+		return NULL;
+
+	ll_dev = ll_free;
+	*ll_root_addr = ll_free->next;
+
+	return ll_dev;
+}
+
+/*
+ * Place an entry back on to the free linked list.
+ */
+static void
+put_data_ll_free_entry(struct virtio_net_data_ll **ll_root_addr,
+	struct virtio_net_data_ll *ll_dev)
+{
+	struct virtio_net_data_ll *ll_free = *ll_root_addr;
+
+	if (ll_dev == NULL)
+		return;
+
+	ll_dev->next = ll_free;
+	*ll_root_addr = ll_dev;
+}
+
+/*
+ * Creates a linked list of a given size.
+ */
+static struct virtio_net_data_ll *
+alloc_data_ll(uint32_t size)
+{
+	struct virtio_net_data_ll *ll_new;
+	uint32_t i;
+
+	/* Malloc and then chain the linked list. */
+	ll_new = malloc(size * sizeof(struct virtio_net_data_ll));
+	if (ll_new == NULL) {
+		RTE_LOG(ERR, VHOST_CONFIG, "Failed to allocate memory for ll_new.\n");
+		return NULL;
+	}
+
+	for (i = 0; i < size - 1; i++) {
+		ll_new[i].dev = NULL;
+		ll_new[i].next = &ll_new[i+1];
+	}
+	ll_new[i].next = NULL;
+
+	return (ll_new);
+}
+
+/*
+ * Create the main linked list along with each individual cores linked list. A used and a free list
+ * are created to manage entries.
+ */
+static int
+init_data_ll (void)
+{
+	int lcore;
+
+	RTE_LCORE_FOREACH_SLAVE(lcore) {
+		lcore_info[lcore].lcore_ll = malloc(sizeof(struct lcore_ll_info));
+		if (lcore_info[lcore].lcore_ll == NULL) {
+			RTE_LOG(ERR, VHOST_CONFIG, "Failed to allocate memory for lcore_ll.\n");
+			return -1;
+		}
+
+		lcore_info[lcore].lcore_ll->device_num = 0;
+		lcore_info[lcore].lcore_ll->dev_removal_flag = ACK_DEV_REMOVAL;
+		lcore_info[lcore].lcore_ll->ll_root_used = NULL;
+		if (num_devices % num_switching_cores)
+			lcore_info[lcore].lcore_ll->ll_root_free = alloc_data_ll((num_devices / num_switching_cores) + 1);
+		else
+			lcore_info[lcore].lcore_ll->ll_root_free = alloc_data_ll(num_devices / num_switching_cores);
+	}
+
+	/* Allocate devices up to a maximum of MAX_DEVICES. */
+	ll_root_free = alloc_data_ll(MIN((num_devices), MAX_DEVICES));
+
+	return 0;
+}
+
+/*
+ * Set virtqueue flags so that we do not receive interrupts.
+ */
+static void
+set_irq_status (struct virtio_net *dev)
+{
+	dev->virtqueue[VIRTIO_RXQ]->used->flags = VRING_USED_F_NO_NOTIFY;
+	dev->virtqueue[VIRTIO_TXQ]->used->flags = VRING_USED_F_NO_NOTIFY;
+}
+
+/*
+ * Remove a device from the specific data core linked list and from the main linked list. Synchonization
+ * occurs through the use of the lcore dev_removal_flag. Device is made volatile here to avoid re-ordering
+ * of dev->remove=1 which can cause an infinite loop in the rte_pause loop.
+ */
+static void
+destroy_device (volatile struct virtio_net *dev)
+{
+	struct virtio_net_data_ll *ll_lcore_dev_cur;
+	struct virtio_net_data_ll *ll_main_dev_cur;
+	struct virtio_net_data_ll *ll_lcore_dev_last = NULL;
+	struct virtio_net_data_ll *ll_main_dev_last = NULL;
+	int lcore;
+
+	dev->flags &= ~VIRTIO_DEV_RUNNING;
+
+	/*set the remove flag. */
+	dev->remove = 1;
+
+	while(dev->ready != DEVICE_SAFE_REMOVE) {
+		rte_pause();
+	}
+
+	/* Search for entry to be removed from lcore ll */
+	ll_lcore_dev_cur = lcore_info[dev->coreid].lcore_ll->ll_root_used;
+	while (ll_lcore_dev_cur != NULL) {
+		if (ll_lcore_dev_cur->dev == dev) {
+			break;
+		} else {
+			ll_lcore_dev_last = ll_lcore_dev_cur;
+			ll_lcore_dev_cur = ll_lcore_dev_cur->next;
+		}
+	}
+
+	if (ll_lcore_dev_cur == NULL) {
+		RTE_LOG(ERR, VHOST_CONFIG,
+			"(%"PRIu64") Failed to find the dev to be destroy.\n",
+			dev->device_fh);
+		return;
+	}
+
+	/* Search for entry to be removed from main ll */
+	ll_main_dev_cur = ll_root_used;
+	ll_main_dev_last = NULL;
+	while (ll_main_dev_cur != NULL) {
+		if (ll_main_dev_cur->dev == dev) {
+			break;
+		} else {
+			ll_main_dev_last = ll_main_dev_cur;
+			ll_main_dev_cur = ll_main_dev_cur->next;
+		}
+	}
+
+	/* Remove entries from the lcore and main ll. */
+	rm_data_ll_entry(&lcore_info[ll_lcore_dev_cur->dev->coreid].lcore_ll->ll_root_used, ll_lcore_dev_cur, ll_lcore_dev_last);
+	rm_data_ll_entry(&ll_root_used, ll_main_dev_cur, ll_main_dev_last);
+
+	/* Set the dev_removal_flag on each lcore. */
+	RTE_LCORE_FOREACH_SLAVE(lcore) {
+		lcore_info[lcore].lcore_ll->dev_removal_flag = REQUEST_DEV_REMOVAL;
+	}
+
+	/*
+	 * Once each core has set the dev_removal_flag to ACK_DEV_REMOVAL we can be sure that
+	 * they can no longer access the device removed from the linked lists and that the devices
+	 * are no longer in use.
+	 */
+	RTE_LCORE_FOREACH_SLAVE(lcore) {
+		while (lcore_info[lcore].lcore_ll->dev_removal_flag != ACK_DEV_REMOVAL) {
+			rte_pause();
+		}
+	}
+
+	/* Add the entries back to the lcore and main free ll.*/
+	put_data_ll_free_entry(&lcore_info[ll_lcore_dev_cur->dev->coreid].lcore_ll->ll_root_free, ll_lcore_dev_cur);
+	put_data_ll_free_entry(&ll_root_free, ll_main_dev_cur);
+
+	/* Decrement number of device on the lcore. */
+	lcore_info[ll_lcore_dev_cur->dev->coreid].lcore_ll->device_num--;
+
+	RTE_LOG(INFO, VHOST_DATA, "(%"PRIu64") Device has been removed from data core\n", dev->device_fh);
+
+	if (zero_copy) {
+		struct vpool *vpool = &vpool_array[dev->vmdq_rx_q];
+
+		/* Stop the RX queue. */
+		if (rte_eth_dev_rx_queue_stop(ports[0], dev->vmdq_rx_q) != 0) {
+			LOG_DEBUG(VHOST_CONFIG,
+				"(%"PRIu64") In destroy_device: Failed to stop "
+				"rx queue:%d\n",
+				dev->device_fh,
+				dev->vmdq_rx_q);
+		}
+
+		LOG_DEBUG(VHOST_CONFIG,
+			"(%"PRIu64") in destroy_device: Start put mbuf in "
+			"mempool back to ring for RX queue: %d\n",
+			dev->device_fh, dev->vmdq_rx_q);
+
+		mbuf_destroy_zcp(vpool);
+
+		/* Stop the TX queue. */
+		if (rte_eth_dev_tx_queue_stop(ports[0], dev->vmdq_rx_q) != 0) {
+			LOG_DEBUG(VHOST_CONFIG,
+				"(%"PRIu64") In destroy_device: Failed to "
+				"stop tx queue:%d\n",
+				dev->device_fh, dev->vmdq_rx_q);
+		}
+
+		vpool = &vpool_array[dev->vmdq_rx_q + MAX_QUEUES];
+
+		LOG_DEBUG(VHOST_CONFIG,
+			"(%"PRIu64") destroy_device: Start put mbuf in mempool "
+			"back to ring for TX queue: %d, dev:(%"PRIu64")\n",
+			dev->device_fh, (dev->vmdq_rx_q + MAX_QUEUES),
+			dev->device_fh);
+
+		mbuf_destroy_zcp(vpool);
+	}
+
+}
+
+/*
+ * A new device is added to a data core. First the device is added to the main linked list
+ * and the allocated to a specific data core.
+ */
+static int
+new_device (struct virtio_net *dev)
+{
+	struct virtio_net_data_ll *ll_dev;
+	int lcore, core_add = 0;
+	uint32_t device_num_min = num_devices;
+
+	/* Add device to main ll */
+	ll_dev = get_data_ll_free_entry(&ll_root_free);
+	if (ll_dev == NULL) {
+		RTE_LOG(INFO, VHOST_DATA, "(%"PRIu64") No free entry found in linked list. Device limit "
+			"of %d devices per core has been reached\n",
+			dev->device_fh, num_devices);
+		return -1;
+	}
+	ll_dev->dev = dev;
+	add_data_ll_entry(&ll_root_used, ll_dev);
+	ll_dev->dev->vmdq_rx_q
+		= ll_dev->dev->device_fh * (num_queues / num_devices);
+
+	if (zero_copy) {
+		uint32_t index = ll_dev->dev->vmdq_rx_q;
+		uint32_t count_in_ring, i;
+		struct mbuf_table *tx_q;
+
+		count_in_ring = rte_ring_count(vpool_array[index].ring);
+
+		LOG_DEBUG(VHOST_CONFIG,
+			"(%"PRIu64") in new_device: mbuf count in mempool "
+			"before attach is: %d\n",
+			dev->device_fh,
+			rte_mempool_count(vpool_array[index].pool));
+		LOG_DEBUG(VHOST_CONFIG,
+			"(%"PRIu64") in new_device: mbuf count in  ring "
+			"before attach  is : %d\n",
+			dev->device_fh, count_in_ring);
+
+		/*
+		 * Attach all mbufs in vpool.ring and put back intovpool.pool.
+		 */
+		for (i = 0; i < count_in_ring; i++)
+			attach_rxmbuf_zcp(dev);
+
+		LOG_DEBUG(VHOST_CONFIG, "(%"PRIu64") in new_device: mbuf count in "
+			"mempool after attach is: %d\n",
+			dev->device_fh,
+			rte_mempool_count(vpool_array[index].pool));
+		LOG_DEBUG(VHOST_CONFIG, "(%"PRIu64") in new_device: mbuf count in "
+			"ring after attach  is : %d\n",
+			dev->device_fh,
+			rte_ring_count(vpool_array[index].ring));
+
+		tx_q = &tx_queue_zcp[(uint16_t)dev->vmdq_rx_q];
+		tx_q->txq_id = dev->vmdq_rx_q;
+
+		if (rte_eth_dev_tx_queue_start(ports[0], dev->vmdq_rx_q) != 0) {
+			struct vpool *vpool = &vpool_array[dev->vmdq_rx_q];
+
+			LOG_DEBUG(VHOST_CONFIG,
+				"(%"PRIu64") In new_device: Failed to start "
+				"tx queue:%d\n",
+				dev->device_fh, dev->vmdq_rx_q);
+
+			mbuf_destroy_zcp(vpool);
+			return -1;
+		}
+
+		if (rte_eth_dev_rx_queue_start(ports[0], dev->vmdq_rx_q) != 0) {
+			struct vpool *vpool = &vpool_array[dev->vmdq_rx_q];
+
+			LOG_DEBUG(VHOST_CONFIG,
+				"(%"PRIu64") In new_device: Failed to start "
+				"rx queue:%d\n",
+				dev->device_fh, dev->vmdq_rx_q);
+
+			/* Stop the TX queue. */
+			if (rte_eth_dev_tx_queue_stop(ports[0],
+				dev->vmdq_rx_q) != 0) {
+				LOG_DEBUG(VHOST_CONFIG,
+					"(%"PRIu64") In new_device: Failed to "
+					"stop tx queue:%d\n",
+					dev->device_fh, dev->vmdq_rx_q);
+			}
+
+			mbuf_destroy_zcp(vpool);
+			return -1;
+		}
+
+	}
+
+	/*reset ready flag*/
+	dev->ready = DEVICE_MAC_LEARNING;
+	dev->remove = 0;
+
+	/* Find a suitable lcore to add the device. */
+	RTE_LCORE_FOREACH_SLAVE(lcore) {
+		if (lcore_info[lcore].lcore_ll->device_num < device_num_min) {
+			device_num_min = lcore_info[lcore].lcore_ll->device_num;
+			core_add = lcore;
+		}
+	}
+	/* Add device to lcore ll */
+	ll_dev->dev->coreid = core_add;
+	ll_dev = get_data_ll_free_entry(&lcore_info[ll_dev->dev->coreid].lcore_ll->ll_root_free);
+	if (ll_dev == NULL) {
+		RTE_LOG(INFO, VHOST_DATA, "(%"PRIu64") Failed to add device to data core\n", dev->device_fh);
+		dev->ready = DEVICE_SAFE_REMOVE;
+		destroy_device(dev);
+		return -1;
+	}
+	ll_dev->dev = dev;
+	add_data_ll_entry(&lcore_info[ll_dev->dev->coreid].lcore_ll->ll_root_used, ll_dev);
+
+	/* Initialize device stats */
+	memset(&dev_statistics[dev->device_fh], 0, sizeof(struct device_statistics));
+
+	/* Disable notifications. */
+	set_irq_status(dev);
+	lcore_info[ll_dev->dev->coreid].lcore_ll->device_num++;
+	dev->flags |= VIRTIO_DEV_RUNNING;
+
+	RTE_LOG(INFO, VHOST_DATA, "(%"PRIu64") Device has been added to data core %d\n", dev->device_fh, dev->coreid);
+
+	return 0;
+}
+
+/*
+ * These callback allow devices to be added to the data core when configuration
+ * has been fully complete.
+ */
+static const struct virtio_net_device_ops virtio_net_device_ops =
+{
+	.new_device =  new_device,
+	.destroy_device = destroy_device,
+};
+
+/*
+ * This is a thread will wake up after a period to print stats if the user has
+ * enabled them.
+ */
+static void
+print_stats(void)
+{
+	struct virtio_net_data_ll *dev_ll;
+	uint64_t tx_dropped, rx_dropped;
+	uint64_t tx, tx_total, rx, rx_total;
+	uint32_t device_fh;
+	const char clr[] = { 27, '[', '2', 'J', '\0' };
+	const char top_left[] = { 27, '[', '1', ';', '1', 'H','\0' };
+
+	while(1) {
+		sleep(enable_stats);
+
+		/* Clear screen and move to top left */
+		printf("%s%s", clr, top_left);
+
+		printf("\nDevice statistics ====================================");
+
+		dev_ll = ll_root_used;
+		while (dev_ll != NULL) {
+			device_fh = (uint32_t)dev_ll->dev->device_fh;
+			tx_total = dev_statistics[device_fh].tx_total;
+			tx = dev_statistics[device_fh].tx;
+			tx_dropped = tx_total - tx;
+			if (zero_copy == 0) {
+				rx_total = rte_atomic64_read(
+					&dev_statistics[device_fh].rx_total_atomic);
+				rx = rte_atomic64_read(
+					&dev_statistics[device_fh].rx_atomic);
+			} else {
+				rx_total = dev_statistics[device_fh].rx_total;
+				rx = dev_statistics[device_fh].rx;
+			}
+			rx_dropped = rx_total - rx;
+
+			printf("\nStatistics for device %"PRIu32" ------------------------------"
+					"\nTX total: 		%"PRIu64""
+					"\nTX dropped: 		%"PRIu64""
+					"\nTX successful: 		%"PRIu64""
+					"\nRX total: 		%"PRIu64""
+					"\nRX dropped: 		%"PRIu64""
+					"\nRX successful: 		%"PRIu64"",
+					device_fh,
+					tx_total,
+					tx_dropped,
+					tx,
+					rx_total,
+					rx_dropped,
+					rx);
+
+			dev_ll = dev_ll->next;
+		}
+		printf("\n======================================================\n");
+	}
+}
+
+static void
+setup_mempool_tbl(int socket, uint32_t index, char *pool_name,
+	char *ring_name, uint32_t nb_mbuf)
+{
+	uint16_t roomsize = VIRTIO_DESCRIPTOR_LEN_ZCP + RTE_PKTMBUF_HEADROOM;
+	vpool_array[index].pool
+		= rte_mempool_create(pool_name, nb_mbuf, MBUF_SIZE_ZCP,
+		MBUF_CACHE_SIZE_ZCP, sizeof(struct rte_pktmbuf_pool_private),
+		rte_pktmbuf_pool_init, (void *)(uintptr_t)roomsize,
+		rte_pktmbuf_init, NULL, socket, 0);
+	if (vpool_array[index].pool != NULL) {
+		vpool_array[index].ring
+			= rte_ring_create(ring_name,
+				rte_align32pow2(nb_mbuf + 1),
+				socket, RING_F_SP_ENQ | RING_F_SC_DEQ);
+		if (likely(vpool_array[index].ring != NULL)) {
+			LOG_DEBUG(VHOST_CONFIG,
+				"in setup_mempool_tbl: mbuf count in "
+				"mempool is: %d\n",
+				rte_mempool_count(vpool_array[index].pool));
+			LOG_DEBUG(VHOST_CONFIG,
+				"in setup_mempool_tbl: mbuf count in "
+				"ring   is: %d\n",
+				rte_ring_count(vpool_array[index].ring));
+		} else {
+			rte_exit(EXIT_FAILURE, "ring_create(%s) failed",
+				ring_name);
+		}
+
+		/* Need consider head room. */
+		vpool_array[index].buf_size = roomsize - RTE_PKTMBUF_HEADROOM;
+	} else {
+		rte_exit(EXIT_FAILURE, "mempool_create(%s) failed", pool_name);
+	}
+}
+
+
+/*
+ * Main function, does initialisation and calls the per-lcore functions. The CUSE
+ * device is also registered here to handle the IOCTLs.
+ */
+int
+MAIN(int argc, char *argv[])
+{
+	struct rte_mempool *mbuf_pool = NULL;
+	unsigned lcore_id, core_id = 0;
+	unsigned nb_ports, valid_num_ports;
+	int ret;
+	uint8_t portid, queue_id = 0;
+	static pthread_t tid;
+
+	/* init EAL */
+	ret = rte_eal_init(argc, argv);
+	if (ret < 0)
+		rte_exit(EXIT_FAILURE, "Error with EAL initialization\n");
+	argc -= ret;
+	argv += ret;
+
+	/* parse app arguments */
+	ret = us_vhost_parse_args(argc, argv);
+	if (ret < 0)
+		rte_exit(EXIT_FAILURE, "Invalid argument\n");
+
+	if (rte_eal_pci_probe() != 0)
+		rte_exit(EXIT_FAILURE, "Error with NIC driver initialization\n");
+
+	for (lcore_id = 0; lcore_id < RTE_MAX_LCORE; lcore_id ++)
+		if (rte_lcore_is_enabled(lcore_id))
+			lcore_ids[core_id ++] = lcore_id;
+
+	if (rte_lcore_count() > RTE_MAX_LCORE)
+		rte_exit(EXIT_FAILURE,"Not enough cores\n");
+
+	/*set the number of swithcing cores available*/
+	num_switching_cores = rte_lcore_count()-1;
+
+	/* Get the number of physical ports. */
+	nb_ports = rte_eth_dev_count();
+	if (nb_ports > RTE_MAX_ETHPORTS)
+		nb_ports = RTE_MAX_ETHPORTS;
+
+	/*
+	 * Update the global var NUM_PORTS and global array PORTS
+	 * and get value of var VALID_NUM_PORTS according to system ports number
+	 */
+	valid_num_ports = check_ports_num(nb_ports);
+
+	if ((valid_num_ports ==  0) || (valid_num_ports > MAX_SUP_PORTS)) {
+		RTE_LOG(INFO, VHOST_PORT, "Current enabled port number is %u,"
+			"but only %u port can be enabled\n",num_ports, MAX_SUP_PORTS);
+		return -1;
+	}
+
+	if (zero_copy == 0) {
+		/* Create the mbuf pool. */
+		mbuf_pool = rte_mempool_create(
+				"MBUF_POOL",
+				NUM_MBUFS_PER_PORT
+				* valid_num_ports,
+				MBUF_SIZE, MBUF_CACHE_SIZE,
+				sizeof(struct rte_pktmbuf_pool_private),
+				rte_pktmbuf_pool_init, NULL,
+				rte_pktmbuf_init, NULL,
+				rte_socket_id(), 0);
+		if (mbuf_pool == NULL)
+			rte_exit(EXIT_FAILURE, "Cannot create mbuf pool\n");
+
+		for (queue_id = 0; queue_id < MAX_QUEUES + 1; queue_id++)
+			vpool_array[queue_id].pool = mbuf_pool;
+
+		if (vm2vm_mode == VM2VM_HARDWARE) {
+			/* Enable VT loop back to let L2 switch to do it. */
+			vmdq_conf_default.rx_adv_conf.vmdq_rx_conf.enable_loop_back = 1;
+			LOG_DEBUG(VHOST_CONFIG,
+				"Enable loop back for L2 switch in vmdq.\n");
+		}
+	} else {
+		uint32_t nb_mbuf;
+		char pool_name[RTE_MEMPOOL_NAMESIZE];
+		char ring_name[RTE_MEMPOOL_NAMESIZE];
+
+		rx_conf_default.start_rx_per_q = (uint8_t)zero_copy;
+		rx_conf_default.rx_drop_en = 0;
+		tx_conf_default.start_tx_per_q = (uint8_t)zero_copy;
+		nb_mbuf = num_rx_descriptor
+			+ num_switching_cores * MBUF_CACHE_SIZE_ZCP
+			+ num_switching_cores * MAX_PKT_BURST;
+
+		for (queue_id = 0; queue_id < MAX_QUEUES; queue_id++) {
+			snprintf(pool_name, sizeof(pool_name),
+				"rxmbuf_pool_%u", queue_id);
+			snprintf(ring_name, sizeof(ring_name),
+				"rxmbuf_ring_%u", queue_id);
+			setup_mempool_tbl(rte_socket_id(), queue_id,
+				pool_name, ring_name, nb_mbuf);
+		}
+
+		nb_mbuf = num_tx_descriptor
+				+ num_switching_cores * MBUF_CACHE_SIZE_ZCP
+				+ num_switching_cores * MAX_PKT_BURST;
+
+		for (queue_id = 0; queue_id < MAX_QUEUES; queue_id++) {
+			snprintf(pool_name, sizeof(pool_name),
+				"txmbuf_pool_%u", queue_id);
+			snprintf(ring_name, sizeof(ring_name),
+				"txmbuf_ring_%u", queue_id);
+			setup_mempool_tbl(rte_socket_id(),
+				(queue_id + MAX_QUEUES),
+				pool_name, ring_name, nb_mbuf);
+		}
+
+		if (vm2vm_mode == VM2VM_HARDWARE) {
+			/* Enable VT loop back to let L2 switch to do it. */
+			vmdq_conf_default.rx_adv_conf.vmdq_rx_conf.enable_loop_back = 1;
+			LOG_DEBUG(VHOST_CONFIG,
+				"Enable loop back for L2 switch in vmdq.\n");
+		}
+	}
+	/* Set log level. */
+	rte_set_log_level(LOG_LEVEL);
+
+	/* initialize all ports */
+	for (portid = 0; portid < nb_ports; portid++) {
+		/* skip ports that are not enabled */
+		if ((enabled_port_mask & (1 << portid)) == 0) {
+			RTE_LOG(INFO, VHOST_PORT,
+				"Skipping disabled port %d\n", portid);
+			continue;
+		}
+		if (port_init(portid) != 0)
+			rte_exit(EXIT_FAILURE,
+				"Cannot initialize network ports\n");
+	}
+
+	/* Initialise all linked lists. */
+	if (init_data_ll() == -1)
+		rte_exit(EXIT_FAILURE, "Failed to initialize linked list\n");
+
+	/* Initialize device stats */
+	memset(&dev_statistics, 0, sizeof(dev_statistics));
+
+	/* Enable stats if the user option is set. */
+	if (enable_stats)
+		pthread_create(&tid, NULL, (void*)print_stats, NULL );
+
+	/* Launch all data cores. */
+	if (zero_copy == 0) {
+		RTE_LCORE_FOREACH_SLAVE(lcore_id) {
+			rte_eal_remote_launch(switch_worker,
+				mbuf_pool, lcore_id);
+		}
+	} else {
+		uint32_t count_in_mempool, index, i;
+		for (index = 0; index < 2*MAX_QUEUES; index++) {
+			/* For all RX and TX queues. */
+			count_in_mempool
+				= rte_mempool_count(vpool_array[index].pool);
+
+			/*
+			 * Transfer all un-attached mbufs from vpool.pool
+			 * to vpoo.ring.
+			 */
+			for (i = 0; i < count_in_mempool; i++) {
+				struct rte_mbuf *mbuf
+					= __rte_mbuf_raw_alloc(
+						vpool_array[index].pool);
+				rte_ring_sp_enqueue(vpool_array[index].ring,
+						(void *)mbuf);
+			}
+
+			LOG_DEBUG(VHOST_CONFIG,
+				"in MAIN: mbuf count in mempool at initial "
+				"is: %d\n", count_in_mempool);
+			LOG_DEBUG(VHOST_CONFIG,
+				"in MAIN: mbuf count in  ring at initial  is :"
+				" %d\n",
+				rte_ring_count(vpool_array[index].ring));
+		}
+
+		RTE_LCORE_FOREACH_SLAVE(lcore_id)
+			rte_eal_remote_launch(switch_worker_zcp, NULL,
+				lcore_id);
+	}
+
+	/* Register CUSE device to handle IOCTLs. */
+	ret = register_cuse_device((char*)&dev_basename, dev_index, get_virtio_net_callbacks());
+	if (ret != 0)
+		rte_exit(EXIT_FAILURE,"CUSE device setup failure.\n");
+
+	init_virtio_net(&virtio_net_device_ops);
+
+	/* Start CUSE session. */
+	start_cuse_session_loop();
+	return 0;
+
+}
+
diff --git a/examples/vhost/main.h b/examples/vhost/main.h
new file mode 100644
index 0000000..c15d938
--- /dev/null
+++ b/examples/vhost/main.h
@@ -0,0 +1,86 @@
+/*-
+ *   BSD LICENSE
+ *
+ *   Copyright(c) 2010-2014 Intel Corporation. All rights reserved.
+ *   All rights reserved.
+ *
+ *   Redistribution and use in source and binary forms, with or without
+ *   modification, are permitted provided that the following conditions
+ *   are met:
+ *
+ *     * Redistributions of source code must retain the above copyright
+ *       notice, this list of conditions and the following disclaimer.
+ *     * Redistributions in binary form must reproduce the above copyright
+ *       notice, this list of conditions and the following disclaimer in
+ *       the documentation and/or other materials provided with the
+ *       distribution.
+ *     * Neither the name of Intel Corporation nor the names of its
+ *       contributors may be used to endorse or promote products derived
+ *       from this software without specific prior written permission.
+ *
+ *   THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ *   "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ *   LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+ *   A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+ *   OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+ *   SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+ *   LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+ *   DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+ *   THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ *   (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+ *   OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#ifndef _MAIN_H_
+#define _MAIN_H_
+
+#ifdef RTE_EXEC_ENV_BAREMETAL
+#define MAIN _main
+#else
+#define MAIN main
+#endif
+
+//#define DEBUG
+
+#ifdef DEBUG
+#define LOG_LEVEL RTE_LOG_DEBUG
+#define LOG_DEBUG(log_type, fmt, args...) do {	\
+	RTE_LOG(DEBUG, log_type, fmt, ##args);		\
+} while (0)
+#else
+#define LOG_LEVEL RTE_LOG_INFO
+#define LOG_DEBUG(log_type, fmt, args...) do{} while(0)
+#endif
+
+/* Macros for printing using RTE_LOG */
+#define RTE_LOGTYPE_VHOST_CONFIG RTE_LOGTYPE_USER1
+#define RTE_LOGTYPE_VHOST_DATA   RTE_LOGTYPE_USER2
+#define RTE_LOGTYPE_VHOST_PORT   RTE_LOGTYPE_USER3
+
+/*
+ * Device linked list structure for data path.
+ */
+struct virtio_net_data_ll
+{
+	struct virtio_net			*dev;	/* Pointer to device created by configuration core. */
+	struct virtio_net_data_ll	*next;  /* Pointer to next device in linked list. */
+};
+
+/*
+ * Structure containing data core specific information.
+ */
+struct lcore_ll_info
+{
+	struct virtio_net_data_ll	*ll_root_free; 		/* Pointer to head in free linked list. */
+	struct virtio_net_data_ll	*ll_root_used;		/* Pointer to head of used linked list. */
+	uint32_t 					device_num;			/* Number of devices on lcore. */
+	volatile uint8_t			dev_removal_flag;	/* Flag to synchronize device removal. */
+};
+
+struct lcore_info
+{
+	struct lcore_ll_info	*lcore_ll;	/* Pointer to data core specific lcore_ll_info struct */
+};
+
+int MAIN(int argc, char **argv);
+#endif /* _MAIN_H_ */
-- 
1.8.1.4

^ permalink raw reply	[flat|nested] 23+ messages in thread

* [dpdk-dev] [PATCH v5 09/11] examples/vhost: vhost example based on vhost lib API
  2014-09-26  9:45 [dpdk-dev] [PATCH v5 00/11] user space vhost library and vhost example Huawei Xie
                   ` (7 preceding siblings ...)
  2014-09-26  9:45 ` [dpdk-dev] [PATCH v5 08/11] examples/vhost: copy old vhost example src file Huawei Xie
@ 2014-09-26  9:45 ` Huawei Xie
  2014-09-26  9:45 ` [dpdk-dev] [PATCH v5 10/11] examples/vhost: merge oliver's mbuf changes to vhost example Huawei Xie
  2014-09-26  9:45 ` [dpdk-dev] [PATCH v5 11/11] examples/vhost: add vhost example Makefile Huawei Xie
  10 siblings, 0 replies; 23+ messages in thread
From: Huawei Xie @ 2014-09-26  9:45 UTC (permalink / raw)
  To: dev

This vhost example demonstrates how to integrate user space vhost
with DPDK accelerated ethernet vSwitch.

Signed-off-by: Huawei Xie <huawei.xie@intel.com>
---
 examples/vhost/main.c | 1455 +++++++++++++------------------------------------
 examples/vhost/main.h |   47 +-
 2 files changed, 431 insertions(+), 1071 deletions(-)

diff --git a/examples/vhost/main.c b/examples/vhost/main.c
index 7d9e6a2..3834af4 100644
--- a/examples/vhost/main.c
+++ b/examples/vhost/main.c
@@ -49,10 +49,9 @@
 #include <rte_log.h>
 #include <rte_string_fns.h>
 #include <rte_malloc.h>
+#include <rte_virtio_net.h>
 
 #include "main.h"
-#include "virtio-net.h"
-#include "vhost-net-cdev.h"
 
 #define MAX_QUEUES 128
 
@@ -100,7 +99,6 @@
 #define TX_WTHRESH 0  /* Default values of TX write-back threshold reg. */
 
 #define MAX_PKT_BURST 32 		/* Max burst size for RX/TX */
-#define MAX_MRG_PKT_BURST 16 	/* Max burst for merge buffers. Set to 1 due to performance issue. */
 #define BURST_TX_DRAIN_US 100 	/* TX drain every ~100us */
 
 #define BURST_RX_WAIT_US 15 	/* Defines how long we wait between retries on RX */
@@ -168,13 +166,14 @@ static uint32_t num_switching_cores = 0;
 
 /* number of devices/queues to support*/
 static uint32_t num_queues = 0;
-uint32_t num_devices = 0;
+static uint32_t num_devices;
 
 /*
  * Enable zero copy, pkts buffer will directly dma to hw descriptor,
  * disabled on default.
  */
 static uint32_t zero_copy;
+static int mergeable;
 
 /* number of descriptors to apply*/
 static uint32_t num_rx_descriptor = RTE_TEST_RX_DESC_DEFAULT_ZCP;
@@ -218,12 +217,6 @@ static uint32_t burst_rx_retry_num = BURST_RX_RETRIES;
 /* Character device basename. Can be set by user. */
 static char dev_basename[MAX_BASENAME_SZ] = "vhost-net";
 
-/* Charater device index. Can be set by user. */
-static uint32_t dev_index = 0;
-
-/* This can be set by the user so it is made available here. */
-extern uint64_t VHOST_FEATURES;
-
 /* Default configuration for rx and tx thresholds etc. */
 static struct rte_eth_rxconf rx_conf_default = {
 	.rx_thresh = {
@@ -678,11 +671,12 @@ us_vhost_parse_args(int argc, char **argv)
 					us_vhost_usage(prgname);
 					return -1;
 				} else {
+					mergeable = !!ret;
 					if (ret) {
 						vmdq_conf_default.rxmode.jumbo_frame = 1;
 						vmdq_conf_default.rxmode.max_rx_pkt_len
 							= JUMBO_FRAME_MAX_SIZE;
-						VHOST_FEATURES = (1ULL << VIRTIO_NET_F_MRG_RXBUF);
+
 					}
 				}
 			}
@@ -708,17 +702,6 @@ us_vhost_parse_args(int argc, char **argv)
 				}
 			}
 
-			/* Set character device index. */
-			if (!strncmp(long_option[option_index].name, "dev-index", MAX_LONG_OPT_SZ)) {
-				ret = parse_num_opt(optarg, INT32_MAX);
-				if (ret == -1) {
-					RTE_LOG(INFO, VHOST_CONFIG, "Invalid argument for character device index [0..N]\n");
-					us_vhost_usage(prgname);
-					return -1;
-				} else
-					dev_index = ret;
-			}
-
 			/* Enable/disable rx/tx zero copy. */
 			if (!strncmp(long_option[option_index].name,
 				"zero-copy", MAX_LONG_OPT_SZ)) {
@@ -867,36 +850,11 @@ static unsigned check_ports_num(unsigned nb_ports)
 #endif
 
 /*
- * Function to convert guest physical addresses to vhost virtual addresses. This
- * is used to convert virtio buffer addresses.
- */
-static inline uint64_t __attribute__((always_inline))
-gpa_to_vva(struct virtio_net *dev, uint64_t guest_pa)
-{
-	struct virtio_memory_regions *region;
-	uint32_t regionidx;
-	uint64_t vhost_va = 0;
-
-	for (regionidx = 0; regionidx < dev->mem->nregions; regionidx++) {
-		region = &dev->mem->regions[regionidx];
-		if ((guest_pa >= region->guest_phys_address) &&
-			(guest_pa <= region->guest_phys_address_end)) {
-			vhost_va = region->address_offset + guest_pa;
-			break;
-		}
-	}
-	LOG_DEBUG(VHOST_DATA, "(%"PRIu64") GPA %p| VVA %p\n",
-		dev->device_fh, (void*)(uintptr_t)guest_pa, (void*)(uintptr_t)vhost_va);
-
-	return vhost_va;
-}
-
-/*
  * Function to convert guest physical addresses to vhost physical addresses.
  * This is used to convert virtio buffer addresses.
  */
 static inline uint64_t __attribute__((always_inline))
-gpa_to_hpa(struct virtio_net *dev, uint64_t guest_pa,
+gpa_to_hpa(struct vhost_dev  *vdev, uint64_t guest_pa,
 	uint32_t buf_len, hpa_type *addr_type)
 {
 	struct virtio_memory_regions_hpa *region;
@@ -905,8 +863,8 @@ gpa_to_hpa(struct virtio_net *dev, uint64_t guest_pa,
 
 	*addr_type = PHYS_ADDR_INVALID;
 
-	for (regionidx = 0; regionidx < dev->mem->nregions_hpa; regionidx++) {
-		region = &dev->mem->regions_hpa[regionidx];
+	for (regionidx = 0; regionidx < vdev->nregions_hpa; regionidx++) {
+		region = &vdev->regions_hpa[regionidx];
 		if ((guest_pa >= region->guest_phys_address) &&
 			(guest_pa <= region->guest_phys_address_end)) {
 			vhost_pa = region->host_phys_addr_offset + guest_pa;
@@ -927,497 +885,6 @@ gpa_to_hpa(struct virtio_net *dev, uint64_t guest_pa,
 }
 
 /*
- * This function adds buffers to the virtio devices RX virtqueue. Buffers can
- * be received from the physical port or from another virtio device. A packet
- * count is returned to indicate the number of packets that were succesfully
- * added to the RX queue. This function works when mergeable is disabled.
- */
-static inline uint32_t __attribute__((always_inline))
-virtio_dev_rx(struct virtio_net *dev, struct rte_mbuf **pkts, uint32_t count)
-{
-	struct vhost_virtqueue *vq;
-	struct vring_desc *desc;
-	struct rte_mbuf *buff;
-	/* The virtio_hdr is initialised to 0. */
-	struct virtio_net_hdr_mrg_rxbuf virtio_hdr = {{0,0,0,0,0,0},0};
-	uint64_t buff_addr = 0;
-	uint64_t buff_hdr_addr = 0;
-	uint32_t head[MAX_PKT_BURST], packet_len = 0;
-	uint32_t head_idx, packet_success = 0;
-	uint32_t retry = 0;
-	uint16_t avail_idx, res_cur_idx;
-	uint16_t res_base_idx, res_end_idx;
-	uint16_t free_entries;
-	uint8_t success = 0;
-
-	LOG_DEBUG(VHOST_DATA, "(%"PRIu64") virtio_dev_rx()\n", dev->device_fh);
-	vq = dev->virtqueue[VIRTIO_RXQ];
-	count = (count > MAX_PKT_BURST) ? MAX_PKT_BURST : count;
-
-	/* As many data cores may want access to available buffers, they need to be reserved. */
-	do {
-		res_base_idx = vq->last_used_idx_res;
-		avail_idx = *((volatile uint16_t *)&vq->avail->idx);
-
-		free_entries = (avail_idx - res_base_idx);
-		/* If retry is enabled and the queue is full then we wait and retry to avoid packet loss. */
-		if (enable_retry && unlikely(count > free_entries)) {
-			for (retry = 0; retry < burst_rx_retry_num; retry++) {
-				rte_delay_us(burst_rx_delay_time);
-				avail_idx =
-					*((volatile uint16_t *)&vq->avail->idx);
-				free_entries = (avail_idx - res_base_idx);
-				if (count <= free_entries)
-					break;
-			}
-		}
-
-		/*check that we have enough buffers*/
-		if (unlikely(count > free_entries))
-			count = free_entries;
-
-		if (count == 0)
-			return 0;
-
-		res_end_idx = res_base_idx + count;
-		/* vq->last_used_idx_res is atomically updated. */
-		success = rte_atomic16_cmpset(&vq->last_used_idx_res, res_base_idx,
-									res_end_idx);
-	} while (unlikely(success == 0));
-	res_cur_idx = res_base_idx;
-	LOG_DEBUG(VHOST_DATA, "(%"PRIu64") Current Index %d| End Index %d\n", dev->device_fh, res_cur_idx, res_end_idx);
-
-	/* Prefetch available ring to retrieve indexes. */
-	rte_prefetch0(&vq->avail->ring[res_cur_idx & (vq->size - 1)]);
-
-	/* Retrieve all of the head indexes first to avoid caching issues. */
-	for (head_idx = 0; head_idx < count; head_idx++)
-		head[head_idx] = vq->avail->ring[(res_cur_idx + head_idx) & (vq->size - 1)];
-
-	/*Prefetch descriptor index. */
-	rte_prefetch0(&vq->desc[head[packet_success]]);
-
-	while (res_cur_idx != res_end_idx) {
-		/* Get descriptor from available ring */
-		desc = &vq->desc[head[packet_success]];
-
-		buff = pkts[packet_success];
-
-		/* Convert from gpa to vva (guest physical addr -> vhost virtual addr) */
-		buff_addr = gpa_to_vva(dev, desc->addr);
-		/* Prefetch buffer address. */
-		rte_prefetch0((void*)(uintptr_t)buff_addr);
-
-		/* Copy virtio_hdr to packet and increment buffer address */
-		buff_hdr_addr = buff_addr;
-		packet_len = rte_pktmbuf_data_len(buff) + vq->vhost_hlen;
-
-		/*
-		 * If the descriptors are chained the header and data are
-		 * placed in separate buffers.
-		 */
-		if (desc->flags & VRING_DESC_F_NEXT) {
-			desc->len = vq->vhost_hlen;
-			desc = &vq->desc[desc->next];
-			/* Buffer address translation. */
-			buff_addr = gpa_to_vva(dev, desc->addr);
-			desc->len = rte_pktmbuf_data_len(buff);
-		} else {
-			buff_addr += vq->vhost_hlen;
-			desc->len = packet_len;
-		}
-
-		/* Update used ring with desc information */
-		vq->used->ring[res_cur_idx & (vq->size - 1)].id = head[packet_success];
-		vq->used->ring[res_cur_idx & (vq->size - 1)].len = packet_len;
-
-		/* Copy mbuf data to buffer */
-		rte_memcpy((void *)(uintptr_t)buff_addr,
-			(const void *)buff->pkt.data,
-			rte_pktmbuf_data_len(buff));
-		PRINT_PACKET(dev, (uintptr_t)buff_addr,
-			rte_pktmbuf_data_len(buff), 0);
-
-		res_cur_idx++;
-		packet_success++;
-
-		rte_memcpy((void *)(uintptr_t)buff_hdr_addr,
-			(const void *)&virtio_hdr, vq->vhost_hlen);
-
-		PRINT_PACKET(dev, (uintptr_t)buff_hdr_addr, vq->vhost_hlen, 1);
-
-		if (res_cur_idx < res_end_idx) {
-			/* Prefetch descriptor index. */
-			rte_prefetch0(&vq->desc[head[packet_success]]);
-		}
-	}
-
-	rte_compiler_barrier();
-
-	/* Wait until it's our turn to add our buffer to the used ring. */
-	while (unlikely(vq->last_used_idx != res_base_idx))
-		rte_pause();
-
-	*(volatile uint16_t *)&vq->used->idx += count;
-	vq->last_used_idx = res_end_idx;
-
-	/* Kick the guest if necessary. */
-	if (!(vq->avail->flags & VRING_AVAIL_F_NO_INTERRUPT))
-		eventfd_write((int)vq->kickfd, 1);
-	return count;
-}
-
-static inline uint32_t __attribute__((always_inline))
-copy_from_mbuf_to_vring(struct virtio_net *dev,
-	uint16_t res_base_idx, uint16_t res_end_idx,
-	struct rte_mbuf *pkt)
-{
-	uint32_t vec_idx = 0;
-	uint32_t entry_success = 0;
-	struct vhost_virtqueue *vq;
-	/* The virtio_hdr is initialised to 0. */
-	struct virtio_net_hdr_mrg_rxbuf virtio_hdr = {
-		{0, 0, 0, 0, 0, 0}, 0};
-	uint16_t cur_idx = res_base_idx;
-	uint64_t vb_addr = 0;
-	uint64_t vb_hdr_addr = 0;
-	uint32_t seg_offset = 0;
-	uint32_t vb_offset = 0;
-	uint32_t seg_avail;
-	uint32_t vb_avail;
-	uint32_t cpy_len, entry_len;
-
-	if (pkt == NULL)
-		return 0;
-
-	LOG_DEBUG(VHOST_DATA, "(%"PRIu64") Current Index %d| "
-		"End Index %d\n",
-		dev->device_fh, cur_idx, res_end_idx);
-
-	/*
-	 * Convert from gpa to vva
-	 * (guest physical addr -> vhost virtual addr)
-	 */
-	vq = dev->virtqueue[VIRTIO_RXQ];
-	vb_addr =
-		gpa_to_vva(dev, vq->buf_vec[vec_idx].buf_addr);
-	vb_hdr_addr = vb_addr;
-
-	/* Prefetch buffer address. */
-	rte_prefetch0((void *)(uintptr_t)vb_addr);
-
-	virtio_hdr.num_buffers = res_end_idx - res_base_idx;
-
-	LOG_DEBUG(VHOST_DATA, "(%"PRIu64") RX: Num merge buffers %d\n",
-		dev->device_fh, virtio_hdr.num_buffers);
-
-	rte_memcpy((void *)(uintptr_t)vb_hdr_addr,
-		(const void *)&virtio_hdr, vq->vhost_hlen);
-
-	PRINT_PACKET(dev, (uintptr_t)vb_hdr_addr, vq->vhost_hlen, 1);
-
-	seg_avail = rte_pktmbuf_data_len(pkt);
-	vb_offset = vq->vhost_hlen;
-	vb_avail =
-		vq->buf_vec[vec_idx].buf_len - vq->vhost_hlen;
-
-	entry_len = vq->vhost_hlen;
-
-	if (vb_avail == 0) {
-		uint32_t desc_idx =
-			vq->buf_vec[vec_idx].desc_idx;
-		vq->desc[desc_idx].len = vq->vhost_hlen;
-
-		if ((vq->desc[desc_idx].flags
-			& VRING_DESC_F_NEXT) == 0) {
-			/* Update used ring with desc information */
-			vq->used->ring[cur_idx & (vq->size - 1)].id
-				= vq->buf_vec[vec_idx].desc_idx;
-			vq->used->ring[cur_idx & (vq->size - 1)].len
-				= entry_len;
-
-			entry_len = 0;
-			cur_idx++;
-			entry_success++;
-		}
-
-		vec_idx++;
-		vb_addr =
-			gpa_to_vva(dev, vq->buf_vec[vec_idx].buf_addr);
-
-		/* Prefetch buffer address. */
-		rte_prefetch0((void *)(uintptr_t)vb_addr);
-		vb_offset = 0;
-		vb_avail = vq->buf_vec[vec_idx].buf_len;
-	}
-
-	cpy_len = RTE_MIN(vb_avail, seg_avail);
-
-	while (cpy_len > 0) {
-		/* Copy mbuf data to vring buffer */
-		rte_memcpy((void *)(uintptr_t)(vb_addr + vb_offset),
-			(const void *)(rte_pktmbuf_mtod(pkt, char*) + seg_offset),
-			cpy_len);
-
-		PRINT_PACKET(dev,
-			(uintptr_t)(vb_addr + vb_offset),
-			cpy_len, 0);
-
-		seg_offset += cpy_len;
-		vb_offset += cpy_len;
-		seg_avail -= cpy_len;
-		vb_avail -= cpy_len;
-		entry_len += cpy_len;
-
-		if (seg_avail != 0) {
-			/*
-			 * The virtio buffer in this vring
-			 * entry reach to its end.
-			 * But the segment doesn't complete.
-			 */
-			if ((vq->desc[vq->buf_vec[vec_idx].desc_idx].flags &
-				VRING_DESC_F_NEXT) == 0) {
-				/* Update used ring with desc information */
-				vq->used->ring[cur_idx & (vq->size - 1)].id
-					= vq->buf_vec[vec_idx].desc_idx;
-				vq->used->ring[cur_idx & (vq->size - 1)].len
-					= entry_len;
-				entry_len = 0;
-				cur_idx++;
-				entry_success++;
-			}
-
-			vec_idx++;
-			vb_addr = gpa_to_vva(dev,
-				vq->buf_vec[vec_idx].buf_addr);
-			vb_offset = 0;
-			vb_avail = vq->buf_vec[vec_idx].buf_len;
-			cpy_len = RTE_MIN(vb_avail, seg_avail);
-		} else {
-			/*
-			 * This current segment complete, need continue to
-			 * check if the whole packet complete or not.
-			 */
-			pkt = pkt->pkt.next;
-			if (pkt != NULL) {
-				/*
-				 * There are more segments.
-				 */
-				if (vb_avail == 0) {
-					/*
-					 * This current buffer from vring is
-					 * used up, need fetch next buffer
-					 * from buf_vec.
-					 */
-					uint32_t desc_idx =
-						vq->buf_vec[vec_idx].desc_idx;
-					vq->desc[desc_idx].len = vb_offset;
-
-					if ((vq->desc[desc_idx].flags &
-						VRING_DESC_F_NEXT) == 0) {
-						uint16_t wrapped_idx =
-							cur_idx & (vq->size - 1);
-						/*
-						 * Update used ring with the
-						 * descriptor information
-						 */
-						vq->used->ring[wrapped_idx].id
-							= desc_idx;
-						vq->used->ring[wrapped_idx].len
-							= entry_len;
-						entry_success++;
-						entry_len = 0;
-						cur_idx++;
-					}
-
-					/* Get next buffer from buf_vec. */
-					vec_idx++;
-					vb_addr = gpa_to_vva(dev,
-						vq->buf_vec[vec_idx].buf_addr);
-					vb_avail =
-						vq->buf_vec[vec_idx].buf_len;
-					vb_offset = 0;
-				}
-
-				seg_offset = 0;
-				seg_avail = rte_pktmbuf_data_len(pkt);
-				cpy_len = RTE_MIN(vb_avail, seg_avail);
-			} else {
-				/*
-				 * This whole packet completes.
-				 */
-				uint32_t desc_idx =
-					vq->buf_vec[vec_idx].desc_idx;
-				vq->desc[desc_idx].len = vb_offset;
-
-				while (vq->desc[desc_idx].flags &
-					VRING_DESC_F_NEXT) {
-					desc_idx = vq->desc[desc_idx].next;
-					 vq->desc[desc_idx].len = 0;
-				}
-
-				/* Update used ring with desc information */
-				vq->used->ring[cur_idx & (vq->size - 1)].id
-					= vq->buf_vec[vec_idx].desc_idx;
-				vq->used->ring[cur_idx & (vq->size - 1)].len
-					= entry_len;
-				entry_len = 0;
-				cur_idx++;
-				entry_success++;
-				seg_avail = 0;
-				cpy_len = RTE_MIN(vb_avail, seg_avail);
-			}
-		}
-	}
-
-	return entry_success;
-}
-
-/*
- * This function adds buffers to the virtio devices RX virtqueue. Buffers can
- * be received from the physical port or from another virtio device. A packet
- * count is returned to indicate the number of packets that were succesfully
- * added to the RX queue. This function works for mergeable RX.
- */
-static inline uint32_t __attribute__((always_inline))
-virtio_dev_merge_rx(struct virtio_net *dev, struct rte_mbuf **pkts,
-	uint32_t count)
-{
-	struct vhost_virtqueue *vq;
-	uint32_t pkt_idx = 0, entry_success = 0;
-	uint32_t retry = 0;
-	uint16_t avail_idx, res_cur_idx;
-	uint16_t res_base_idx, res_end_idx;
-	uint8_t success = 0;
-
-	LOG_DEBUG(VHOST_DATA, "(%"PRIu64") virtio_dev_merge_rx()\n",
-		dev->device_fh);
-	vq = dev->virtqueue[VIRTIO_RXQ];
-	count = RTE_MIN((uint32_t)MAX_PKT_BURST, count);
-
-	if (count == 0)
-		return 0;
-
-	for (pkt_idx = 0; pkt_idx < count; pkt_idx++) {
-		uint32_t secure_len = 0;
-		uint16_t need_cnt;
-		uint32_t vec_idx = 0;
-		uint32_t pkt_len = pkts[pkt_idx]->pkt.pkt_len + vq->vhost_hlen;
-		uint16_t i, id;
-
-		do {
-			/*
-			 * As many data cores may want access to available
-			 * buffers, they need to be reserved.
-			 */
-			res_base_idx = vq->last_used_idx_res;
-			res_cur_idx = res_base_idx;
-
-			do {
-				avail_idx = *((volatile uint16_t *)&vq->avail->idx);
-				if (unlikely(res_cur_idx == avail_idx)) {
-					/*
-					 * If retry is enabled and the queue is
-					 * full then we wait and retry to avoid
-					 * packet loss.
-					 */
-					if (enable_retry) {
-						uint8_t cont = 0;
-						for (retry = 0; retry < burst_rx_retry_num; retry++) {
-							rte_delay_us(burst_rx_delay_time);
-							avail_idx =
-								*((volatile uint16_t *)&vq->avail->idx);
-							if (likely(res_cur_idx != avail_idx)) {
-								cont = 1;
-								break;
-							}
-						}
-						if (cont == 1)
-							continue;
-					}
-
-					LOG_DEBUG(VHOST_DATA,
-						"(%"PRIu64") Failed "
-						"to get enough desc from "
-						"vring\n",
-						dev->device_fh);
-					return pkt_idx;
-				} else {
-					uint16_t wrapped_idx =
-						(res_cur_idx) & (vq->size - 1);
-					uint32_t idx =
-						vq->avail->ring[wrapped_idx];
-					uint8_t next_desc;
-
-					do {
-						next_desc = 0;
-						secure_len += vq->desc[idx].len;
-						if (vq->desc[idx].flags &
-							VRING_DESC_F_NEXT) {
-							idx = vq->desc[idx].next;
-							next_desc = 1;
-						}
-					} while (next_desc);
-
-					res_cur_idx++;
-				}
-			} while (pkt_len > secure_len);
-
-			/* vq->last_used_idx_res is atomically updated. */
-			success = rte_atomic16_cmpset(&vq->last_used_idx_res,
-							res_base_idx,
-							res_cur_idx);
-		} while (success == 0);
-
-		id = res_base_idx;
-		need_cnt = res_cur_idx - res_base_idx;
-
-		for (i = 0; i < need_cnt; i++, id++) {
-			uint16_t wrapped_idx = id & (vq->size - 1);
-			uint32_t idx = vq->avail->ring[wrapped_idx];
-			uint8_t next_desc;
-			do {
-				next_desc = 0;
-				vq->buf_vec[vec_idx].buf_addr =
-					vq->desc[idx].addr;
-				vq->buf_vec[vec_idx].buf_len =
-					vq->desc[idx].len;
-				vq->buf_vec[vec_idx].desc_idx = idx;
-				vec_idx++;
-
-				if (vq->desc[idx].flags & VRING_DESC_F_NEXT) {
-					idx = vq->desc[idx].next;
-					next_desc = 1;
-				}
-			} while (next_desc);
-		}
-
-		res_end_idx = res_cur_idx;
-
-		entry_success = copy_from_mbuf_to_vring(dev, res_base_idx,
-			res_end_idx, pkts[pkt_idx]);
-
-		rte_compiler_barrier();
-
-		/*
-		 * Wait until it's our turn to add our buffer
-		 * to the used ring.
-		 */
-		while (unlikely(vq->last_used_idx != res_base_idx))
-			rte_pause();
-
-		*(volatile uint16_t *)&vq->used->idx += entry_success;
-		vq->last_used_idx = res_end_idx;
-
-		/* Kick the guest if necessary. */
-		if (!(vq->avail->flags & VRING_AVAIL_F_NO_INTERRUPT))
-			eventfd_write((int)vq->kickfd, 1);
-	}
-
-	return count;
-}
-
-/*
  * Compares a packet destination MAC address to a device MAC address.
  */
 static inline int __attribute__((always_inline))
@@ -1431,10 +898,11 @@ ether_addr_cmp(struct ether_addr *ea, struct ether_addr *eb)
  * vlan tag to a VMDQ.
  */
 static int
-link_vmdq(struct virtio_net *dev, struct rte_mbuf *m)
+link_vmdq(struct vhost_dev *vdev, struct rte_mbuf *m)
 {
 	struct ether_hdr *pkt_hdr;
 	struct virtio_net_data_ll *dev_ll;
+	struct virtio_net *dev = vdev->dev;
 	int i, ret;
 
 	/* Learn MAC address of guest device from packet */
@@ -1443,7 +911,7 @@ link_vmdq(struct virtio_net *dev, struct rte_mbuf *m)
 	dev_ll = ll_root_used;
 
 	while (dev_ll != NULL) {
-		if (ether_addr_cmp(&(pkt_hdr->s_addr), &dev_ll->dev->mac_address)) {
+		if (ether_addr_cmp(&(pkt_hdr->s_addr), &dev_ll->vdev->mac_address)) {
 			RTE_LOG(INFO, VHOST_DATA, "(%"PRIu64") WARNING: This device is using an existing MAC address and has not been registered.\n", dev->device_fh);
 			return -1;
 		}
@@ -1451,30 +919,30 @@ link_vmdq(struct virtio_net *dev, struct rte_mbuf *m)
 	}
 
 	for (i = 0; i < ETHER_ADDR_LEN; i++)
-		dev->mac_address.addr_bytes[i] = pkt_hdr->s_addr.addr_bytes[i];
+		vdev->mac_address.addr_bytes[i] = pkt_hdr->s_addr.addr_bytes[i];
 
 	/* vlan_tag currently uses the device_id. */
-	dev->vlan_tag = vlan_tags[dev->device_fh];
+	vdev->vlan_tag = vlan_tags[dev->device_fh];
 
 	/* Print out VMDQ registration info. */
 	RTE_LOG(INFO, VHOST_DATA, "(%"PRIu64") MAC_ADDRESS %02x:%02x:%02x:%02x:%02x:%02x and VLAN_TAG %d registered\n",
 		dev->device_fh,
-		dev->mac_address.addr_bytes[0], dev->mac_address.addr_bytes[1],
-		dev->mac_address.addr_bytes[2], dev->mac_address.addr_bytes[3],
-		dev->mac_address.addr_bytes[4], dev->mac_address.addr_bytes[5],
-		dev->vlan_tag);
+		vdev->mac_address.addr_bytes[0], vdev->mac_address.addr_bytes[1],
+		vdev->mac_address.addr_bytes[2], vdev->mac_address.addr_bytes[3],
+		vdev->mac_address.addr_bytes[4], vdev->mac_address.addr_bytes[5],
+		vdev->vlan_tag);
 
 	/* Register the MAC address. */
-	ret = rte_eth_dev_mac_addr_add(ports[0], &dev->mac_address, (uint32_t)dev->device_fh);
+	ret = rte_eth_dev_mac_addr_add(ports[0], &vdev->mac_address, (uint32_t)dev->device_fh);
 	if (ret)
 		RTE_LOG(ERR, VHOST_DATA, "(%"PRIu64") Failed to add device MAC address to VMDQ\n",
 					dev->device_fh);
 
 	/* Enable stripping of the vlan tag as we handle routing. */
-	rte_eth_dev_set_vlan_strip_on_queue(ports[0], (uint16_t)dev->vmdq_rx_q, 1);
+	rte_eth_dev_set_vlan_strip_on_queue(ports[0], (uint16_t)vdev->vmdq_rx_q, 1);
 
 	/* Set device as ready for RX. */
-	dev->ready = DEVICE_RX;
+	vdev->ready = DEVICE_RX;
 
 	return 0;
 }
@@ -1484,33 +952,33 @@ link_vmdq(struct virtio_net *dev, struct rte_mbuf *m)
  * queue before disabling RX on the device.
  */
 static inline void
-unlink_vmdq(struct virtio_net *dev)
+unlink_vmdq(struct vhost_dev *vdev)
 {
 	unsigned i = 0;
 	unsigned rx_count;
 	struct rte_mbuf *pkts_burst[MAX_PKT_BURST];
 
-	if (dev->ready == DEVICE_RX) {
+	if (vdev->ready == DEVICE_RX) {
 		/*clear MAC and VLAN settings*/
-		rte_eth_dev_mac_addr_remove(ports[0], &dev->mac_address);
+		rte_eth_dev_mac_addr_remove(ports[0], &vdev->mac_address);
 		for (i = 0; i < 6; i++)
-			dev->mac_address.addr_bytes[i] = 0;
+			vdev->mac_address.addr_bytes[i] = 0;
 
-		dev->vlan_tag = 0;
+		vdev->vlan_tag = 0;
 
 		/*Clear out the receive buffers*/
 		rx_count = rte_eth_rx_burst(ports[0],
-					(uint16_t)dev->vmdq_rx_q, pkts_burst, MAX_PKT_BURST);
+					(uint16_t)vdev->vmdq_rx_q, pkts_burst, MAX_PKT_BURST);
 
 		while (rx_count) {
 			for (i = 0; i < rx_count; i++)
 				rte_pktmbuf_free(pkts_burst[i]);
 
 			rx_count = rte_eth_rx_burst(ports[0],
-					(uint16_t)dev->vmdq_rx_q, pkts_burst, MAX_PKT_BURST);
+					(uint16_t)vdev->vmdq_rx_q, pkts_burst, MAX_PKT_BURST);
 		}
 
-		dev->ready = DEVICE_MAC_LEARNING;
+		vdev->ready = DEVICE_MAC_LEARNING;
 	}
 }
 
@@ -1518,12 +986,14 @@ unlink_vmdq(struct virtio_net *dev)
  * Check if the packet destination MAC address is for a local device. If so then put
  * the packet on that devices RX queue. If not then return.
  */
-static inline unsigned __attribute__((always_inline))
-virtio_tx_local(struct virtio_net *dev, struct rte_mbuf *m)
+static inline int __attribute__((always_inline))
+virtio_tx_local(struct vhost_dev *vdev, struct rte_mbuf *m)
 {
 	struct virtio_net_data_ll *dev_ll;
 	struct ether_hdr *pkt_hdr;
 	uint64_t ret = 0;
+	struct virtio_net *dev = vdev->dev;
+	struct virtio_net *tdev; /* destination virito device */
 
 	pkt_hdr = (struct ether_hdr *)m->pkt.data;
 
@@ -1531,43 +1001,34 @@ virtio_tx_local(struct virtio_net *dev, struct rte_mbuf *m)
 	dev_ll = ll_root_used;
 
 	while (dev_ll != NULL) {
-		if ((dev_ll->dev->ready == DEVICE_RX) && ether_addr_cmp(&(pkt_hdr->d_addr),
-				          &dev_ll->dev->mac_address)) {
+		if ((dev_ll->vdev->ready == DEVICE_RX) && ether_addr_cmp(&(pkt_hdr->d_addr),
+			&dev_ll->vdev->mac_address)) {
 
 			/* Drop the packet if the TX packet is destined for the TX device. */
-			if (dev_ll->dev->device_fh == dev->device_fh) {
+			if (dev_ll->vdev->dev->device_fh == dev->device_fh) {
 				LOG_DEBUG(VHOST_DATA, "(%"PRIu64") TX: Source and destination MAC addresses are the same. Dropping packet.\n",
-							dev_ll->dev->device_fh);
+							dev->device_fh);
 				return 0;
 			}
+			tdev = dev_ll->vdev->dev;
 
+			LOG_DEBUG(VHOST_DATA, "(%"PRIu64") TX: MAC address is local\n", tdev->device_fh);
 
-			LOG_DEBUG(VHOST_DATA, "(%"PRIu64") TX: MAC address is local\n", dev_ll->dev->device_fh);
-
-			if (dev_ll->dev->remove) {
+			if (unlikely(dev_ll->vdev->remove)) {
 				/*drop the packet if the device is marked for removal*/
-				LOG_DEBUG(VHOST_DATA, "(%"PRIu64") Device is marked for removal\n", dev_ll->dev->device_fh);
+				LOG_DEBUG(VHOST_DATA, "(%"PRIu64") Device is marked for removal\n", tdev->device_fh);
 			} else {
-				uint32_t mergeable =
-					dev_ll->dev->features &
-					(1 << VIRTIO_NET_F_MRG_RXBUF);
-
 				/*send the packet to the local virtio device*/
-				if (likely(mergeable == 0))
-					ret = virtio_dev_rx(dev_ll->dev, &m, 1);
-				else
-					ret = virtio_dev_merge_rx(dev_ll->dev,
-						&m, 1);
-
+				ret = rte_vhost_enqueue_burst(tdev, VIRTIO_RXQ, &m, 1);
 				if (enable_stats) {
 					rte_atomic64_add(
-					&dev_statistics[dev_ll->dev->device_fh].rx_total_atomic,
+					&dev_statistics[tdev->device_fh].rx_total_atomic,
 					1);
 					rte_atomic64_add(
-					&dev_statistics[dev_ll->dev->device_fh].rx_atomic,
+					&dev_statistics[tdev->device_fh].rx_atomic,
 					ret);
-					dev_statistics[dev->device_fh].tx_total++;
-					dev_statistics[dev->device_fh].tx += ret;
+					dev_statistics[tdev->device_fh].tx_total++;
+					dev_statistics[tdev->device_fh].tx += ret;
 				}
 			}
 
@@ -1584,47 +1045,49 @@ virtio_tx_local(struct virtio_net *dev, struct rte_mbuf *m)
  * or the physical port.
  */
 static inline void __attribute__((always_inline))
-virtio_tx_route(struct virtio_net* dev, struct rte_mbuf *m, struct rte_mempool *mbuf_pool, uint16_t vlan_tag)
+virtio_tx_route(struct vhost_dev *vdev, struct rte_mbuf *m, struct rte_mempool *mbuf_pool, uint16_t vlan_tag)
 {
 	struct mbuf_table *tx_q;
-	struct vlan_ethhdr *vlan_hdr;
 	struct rte_mbuf **m_table;
-	struct rte_mbuf *mbuf, *prev;
 	unsigned len, ret, offset = 0;
 	const uint16_t lcore_id = rte_lcore_id();
 	struct virtio_net_data_ll *dev_ll = ll_root_used;
 	struct ether_hdr *pkt_hdr = (struct ether_hdr *)m->pkt.data;
+	struct virtio_net *dev = vdev->dev;
 
-	/*check if destination is local VM*/
-	if ((vm2vm_mode == VM2VM_SOFTWARE) && (virtio_tx_local(dev, m) == 0))
+	/*heck if destination is local VM*/
+	if (vm2vm_mode == VM2VM_SOFTWARE && (virtio_tx_local(vdev, m) == 0)) {
+		rte_pktmbuf_free(m);
 		return;
+	}
 
 	if (vm2vm_mode == VM2VM_HARDWARE) {
 		while (dev_ll != NULL) {
-			if ((dev_ll->dev->ready == DEVICE_RX)
+			if ((dev_ll->vdev->ready == DEVICE_RX)
 				&& ether_addr_cmp(&(pkt_hdr->d_addr),
-				&dev_ll->dev->mac_address)) {
+				&dev_ll->vdev->mac_address)) {
 				/*
 				 * Drop the packet if the TX packet is
 				 * destined for the TX device.
 				 */
-				if (dev_ll->dev->device_fh == dev->device_fh) {
+				if (dev_ll->vdev->dev->device_fh == dev->device_fh) {
 					LOG_DEBUG(VHOST_DATA,
 					"(%"PRIu64") TX: Source and destination"
 					" MAC addresses are the same. Dropping "
 					"packet.\n",
-					dev_ll->dev->device_fh);
+					dev_ll->vdev->device_fh);
+					rte_pktmbuf_free(m);
 					return;
 				}
 				offset = 4;
 				vlan_tag =
 				(uint16_t)
-				vlan_tags[(uint16_t)dev_ll->dev->device_fh];
+				vlan_tags[(uint16_t)dev_ll->vdev->dev->device_fh];
 
 				LOG_DEBUG(VHOST_DATA,
 				"(%"PRIu64") TX: pkt to local VM device id:"
 				"(%"PRIu64") vlan tag: %d.\n",
-				dev->device_fh, dev_ll->dev->device_fh,
+				dev->device_fh, dev_ll->vdev->dev->device_fh,
 				vlan_tag);
 
 				break;
@@ -1639,55 +1102,12 @@ virtio_tx_route(struct virtio_net* dev, struct rte_mbuf *m, struct rte_mempool *
 	tx_q = &lcore_tx_queue[lcore_id];
 	len = tx_q->len;
 
-	/* Allocate an mbuf and populate the structure. */
-	mbuf = rte_pktmbuf_alloc(mbuf_pool);
-	if (unlikely(mbuf == NULL)) {
-		RTE_LOG(ERR, VHOST_DATA,
-			"Failed to allocate memory for mbuf.\n");
-		return;
-	}
-
-	mbuf->pkt.data_len = m->pkt.data_len + VLAN_HLEN + offset;
-	mbuf->pkt.pkt_len = m->pkt.pkt_len + VLAN_HLEN + offset;
-	mbuf->pkt.nb_segs = m->pkt.nb_segs;
-
-	/* Copy ethernet header to mbuf. */
-	rte_memcpy((void*)mbuf->pkt.data, (const void*)m->pkt.data, ETH_HLEN);
-
-
-	/* Setup vlan header. Bytes need to be re-ordered for network with htons()*/
-	vlan_hdr = (struct vlan_ethhdr *) mbuf->pkt.data;
-	vlan_hdr->h_vlan_encapsulated_proto = vlan_hdr->h_vlan_proto;
-	vlan_hdr->h_vlan_proto = htons(ETH_P_8021Q);
-	vlan_hdr->h_vlan_TCI = htons(vlan_tag);
-
-	/* Copy the remaining packet contents to the mbuf. */
-	rte_memcpy((void*) ((uint8_t*)mbuf->pkt.data + VLAN_ETH_HLEN),
-		(const void*) ((uint8_t*)m->pkt.data + ETH_HLEN), (m->pkt.data_len - ETH_HLEN));
-
-	/* Copy the remaining segments for the whole packet. */
-	prev = mbuf;
-	while (m->pkt.next) {
-		/* Allocate an mbuf and populate the structure. */
-		struct rte_mbuf *next_mbuf = rte_pktmbuf_alloc(mbuf_pool);
-		if (unlikely(next_mbuf == NULL)) {
-			rte_pktmbuf_free(mbuf);
-			RTE_LOG(ERR, VHOST_DATA,
-				"Failed to allocate memory for mbuf.\n");
-			return;
-		}
-
-		m = m->pkt.next;
-		prev->pkt.next = next_mbuf;
-		prev = next_mbuf;
-		next_mbuf->pkt.data_len = m->pkt.data_len;
+	m->ol_flags = PKT_TX_VLAN_PKT;
+	/*FIXME: offset*/
+	m->pkt.data_len += offset;
+	m->pkt.vlan_macip.f.vlan_tci = vlan_tag;
 
-		/* Copy data to next mbuf. */
-		rte_memcpy(rte_pktmbuf_mtod(next_mbuf, void *),
-			rte_pktmbuf_mtod(m, const void *), m->pkt.data_len);
-	}
-
-	tx_q->m_table[len] = mbuf;
+	tx_q->m_table[len] = m;
 	len++;
 	if (enable_stats) {
 		dev_statistics[dev->device_fh].tx_total++;
@@ -1710,321 +1130,6 @@ virtio_tx_route(struct virtio_net* dev, struct rte_mbuf *m, struct rte_mempool *
 	tx_q->len = len;
 	return;
 }
-
-static inline void __attribute__((always_inline))
-virtio_dev_tx(struct virtio_net* dev, struct rte_mempool *mbuf_pool)
-{
-	struct rte_mbuf m;
-	struct vhost_virtqueue *vq;
-	struct vring_desc *desc;
-	uint64_t buff_addr = 0;
-	uint32_t head[MAX_PKT_BURST];
-	uint32_t used_idx;
-	uint32_t i;
-	uint16_t free_entries, packet_success = 0;
-	uint16_t avail_idx;
-
-	vq = dev->virtqueue[VIRTIO_TXQ];
-	avail_idx =  *((volatile uint16_t *)&vq->avail->idx);
-
-	/* If there are no available buffers then return. */
-	if (vq->last_used_idx == avail_idx)
-		return;
-
-	LOG_DEBUG(VHOST_DATA, "(%"PRIu64") virtio_dev_tx()\n", dev->device_fh);
-
-	/* Prefetch available ring to retrieve head indexes. */
-	rte_prefetch0(&vq->avail->ring[vq->last_used_idx & (vq->size - 1)]);
-
-	/*get the number of free entries in the ring*/
-	free_entries = (avail_idx - vq->last_used_idx);
-
-	/* Limit to MAX_PKT_BURST. */
-	if (free_entries > MAX_PKT_BURST)
-		free_entries = MAX_PKT_BURST;
-
-	LOG_DEBUG(VHOST_DATA, "(%"PRIu64") Buffers available %d\n", dev->device_fh, free_entries);
-	/* Retrieve all of the head indexes first to avoid caching issues. */
-	for (i = 0; i < free_entries; i++)
-		head[i] = vq->avail->ring[(vq->last_used_idx + i) & (vq->size - 1)];
-
-	/* Prefetch descriptor index. */
-	rte_prefetch0(&vq->desc[head[packet_success]]);
-	rte_prefetch0(&vq->used->ring[vq->last_used_idx & (vq->size - 1)]);
-
-	while (packet_success < free_entries) {
-		desc = &vq->desc[head[packet_success]];
-
-		/* Discard first buffer as it is the virtio header */
-		desc = &vq->desc[desc->next];
-
-		/* Buffer address translation. */
-		buff_addr = gpa_to_vva(dev, desc->addr);
-		/* Prefetch buffer address. */
-		rte_prefetch0((void*)(uintptr_t)buff_addr);
-
-		used_idx = vq->last_used_idx & (vq->size - 1);
-
-		if (packet_success < (free_entries - 1)) {
-			/* Prefetch descriptor index. */
-			rte_prefetch0(&vq->desc[head[packet_success+1]]);
-			rte_prefetch0(&vq->used->ring[(used_idx + 1) & (vq->size - 1)]);
-		}
-
-		/* Update used index buffer information. */
-		vq->used->ring[used_idx].id = head[packet_success];
-		vq->used->ring[used_idx].len = 0;
-
-		/* Setup dummy mbuf. This is copied to a real mbuf if transmitted out the physical port. */
-		m.pkt.data_len = desc->len;
-		m.pkt.pkt_len = desc->len;
-		m.pkt.data = (void*)(uintptr_t)buff_addr;
-
-		PRINT_PACKET(dev, (uintptr_t)buff_addr, desc->len, 0);
-
-		/* If this is the first received packet we need to learn the MAC and setup VMDQ */
-		if (dev->ready == DEVICE_MAC_LEARNING) {
-			if (dev->remove || (link_vmdq(dev, &m) == -1)) {
-				/*discard frame if device is scheduled for removal or a duplicate MAC address is found. */
-				packet_success += free_entries;
-				vq->last_used_idx += packet_success;
-				break;
-			}
-		}
-		virtio_tx_route(dev, &m, mbuf_pool, (uint16_t)dev->device_fh);
-
-		vq->last_used_idx++;
-		packet_success++;
-	}
-
-	rte_compiler_barrier();
-	vq->used->idx += packet_success;
-	/* Kick guest if required. */
-	if (!(vq->avail->flags & VRING_AVAIL_F_NO_INTERRUPT))
-		eventfd_write((int)vq->kickfd, 1);
-}
-
-/* This function works for TX packets with mergeable feature enabled. */
-static inline void __attribute__((always_inline))
-virtio_dev_merge_tx(struct virtio_net *dev, struct rte_mempool *mbuf_pool)
-{
-	struct rte_mbuf *m, *prev;
-	struct vhost_virtqueue *vq;
-	struct vring_desc *desc;
-	uint64_t vb_addr = 0;
-	uint32_t head[MAX_PKT_BURST];
-	uint32_t used_idx;
-	uint32_t i;
-	uint16_t free_entries, entry_success = 0;
-	uint16_t avail_idx;
-	uint32_t buf_size = MBUF_SIZE - (sizeof(struct rte_mbuf)
-			+ RTE_PKTMBUF_HEADROOM);
-
-	vq = dev->virtqueue[VIRTIO_TXQ];
-	avail_idx =  *((volatile uint16_t *)&vq->avail->idx);
-
-	/* If there are no available buffers then return. */
-	if (vq->last_used_idx == avail_idx)
-		return;
-
-	LOG_DEBUG(VHOST_DATA, "(%"PRIu64") virtio_dev_merge_tx()\n",
-		dev->device_fh);
-
-	/* Prefetch available ring to retrieve head indexes. */
-	rte_prefetch0(&vq->avail->ring[vq->last_used_idx & (vq->size - 1)]);
-
-	/*get the number of free entries in the ring*/
-	free_entries = (avail_idx - vq->last_used_idx);
-
-	/* Limit to MAX_PKT_BURST. */
-	free_entries = RTE_MIN(free_entries, MAX_PKT_BURST);
-
-	LOG_DEBUG(VHOST_DATA, "(%"PRIu64") Buffers available %d\n",
-		dev->device_fh, free_entries);
-	/* Retrieve all of the head indexes first to avoid caching issues. */
-	for (i = 0; i < free_entries; i++)
-		head[i] = vq->avail->ring[(vq->last_used_idx + i) & (vq->size - 1)];
-
-	/* Prefetch descriptor index. */
-	rte_prefetch0(&vq->desc[head[entry_success]]);
-	rte_prefetch0(&vq->used->ring[vq->last_used_idx & (vq->size - 1)]);
-
-	while (entry_success < free_entries) {
-		uint32_t vb_avail, vb_offset;
-		uint32_t seg_avail, seg_offset;
-		uint32_t cpy_len;
-		uint32_t seg_num = 0;
-		struct rte_mbuf *cur;
-		uint8_t alloc_err = 0;
-
-		desc = &vq->desc[head[entry_success]];
-
-		/* Discard first buffer as it is the virtio header */
-		desc = &vq->desc[desc->next];
-
-		/* Buffer address translation. */
-		vb_addr = gpa_to_vva(dev, desc->addr);
-		/* Prefetch buffer address. */
-		rte_prefetch0((void *)(uintptr_t)vb_addr);
-
-		used_idx = vq->last_used_idx & (vq->size - 1);
-
-		if (entry_success < (free_entries - 1)) {
-			/* Prefetch descriptor index. */
-			rte_prefetch0(&vq->desc[head[entry_success+1]]);
-			rte_prefetch0(&vq->used->ring[(used_idx + 1) & (vq->size - 1)]);
-		}
-
-		/* Update used index buffer information. */
-		vq->used->ring[used_idx].id = head[entry_success];
-		vq->used->ring[used_idx].len = 0;
-
-		vb_offset = 0;
-		vb_avail = desc->len;
-		seg_offset = 0;
-		seg_avail = buf_size;
-		cpy_len = RTE_MIN(vb_avail, seg_avail);
-
-		PRINT_PACKET(dev, (uintptr_t)vb_addr, desc->len, 0);
-
-		/* Allocate an mbuf and populate the structure. */
-		m = rte_pktmbuf_alloc(mbuf_pool);
-		if (unlikely(m == NULL)) {
-			RTE_LOG(ERR, VHOST_DATA,
-				"Failed to allocate memory for mbuf.\n");
-			return;
-		}
-
-		seg_num++;
-		cur = m;
-		prev = m;
-		while (cpy_len != 0) {
-			rte_memcpy((void *)(rte_pktmbuf_mtod(cur, char *) + seg_offset),
-				(void *)((uintptr_t)(vb_addr + vb_offset)),
-				cpy_len);
-
-			seg_offset += cpy_len;
-			vb_offset += cpy_len;
-			vb_avail -= cpy_len;
-			seg_avail -= cpy_len;
-
-			if (vb_avail != 0) {
-				/*
-				 * The segment reachs to its end,
-				 * while the virtio buffer in TX vring has
-				 * more data to be copied.
-				 */
-				cur->pkt.data_len = seg_offset;
-				m->pkt.pkt_len += seg_offset;
-				/* Allocate mbuf and populate the structure. */
-				cur = rte_pktmbuf_alloc(mbuf_pool);
-				if (unlikely(cur == NULL)) {
-					RTE_LOG(ERR, VHOST_DATA, "Failed to "
-						"allocate memory for mbuf.\n");
-					rte_pktmbuf_free(m);
-					alloc_err = 1;
-					break;
-				}
-
-				seg_num++;
-				prev->pkt.next = cur;
-				prev = cur;
-				seg_offset = 0;
-				seg_avail = buf_size;
-			} else {
-				if (desc->flags & VRING_DESC_F_NEXT) {
-					/*
-					 * There are more virtio buffers in
-					 * same vring entry need to be copied.
-					 */
-					if (seg_avail == 0) {
-						/*
-						 * The current segment hasn't
-						 * room to accomodate more
-						 * data.
-						 */
-						cur->pkt.data_len = seg_offset;
-						m->pkt.pkt_len += seg_offset;
-						/*
-						 * Allocate an mbuf and
-						 * populate the structure.
-						 */
-						cur = rte_pktmbuf_alloc(mbuf_pool);
-						if (unlikely(cur == NULL)) {
-							RTE_LOG(ERR,
-								VHOST_DATA,
-								"Failed to "
-								"allocate memory "
-								"for mbuf\n");
-							rte_pktmbuf_free(m);
-							alloc_err = 1;
-							break;
-						}
-						seg_num++;
-						prev->pkt.next = cur;
-						prev = cur;
-						seg_offset = 0;
-						seg_avail = buf_size;
-					}
-
-					desc = &vq->desc[desc->next];
-
-					/* Buffer address translation. */
-					vb_addr = gpa_to_vva(dev, desc->addr);
-					/* Prefetch buffer address. */
-					rte_prefetch0((void *)(uintptr_t)vb_addr);
-					vb_offset = 0;
-					vb_avail = desc->len;
-
-					PRINT_PACKET(dev, (uintptr_t)vb_addr,
-						desc->len, 0);
-				} else {
-					/* The whole packet completes. */
-					cur->pkt.data_len = seg_offset;
-					m->pkt.pkt_len += seg_offset;
-					vb_avail = 0;
-				}
-			}
-
-			cpy_len = RTE_MIN(vb_avail, seg_avail);
-		}
-
-		if (unlikely(alloc_err == 1))
-			break;
-
-		m->pkt.nb_segs = seg_num;
-
-		/*
-		 * If this is the first received packet we need to learn
-		 * the MAC and setup VMDQ
-		 */
-		if (dev->ready == DEVICE_MAC_LEARNING) {
-			if (dev->remove || (link_vmdq(dev, m) == -1)) {
-				/*
-				 * Discard frame if device is scheduled for
-				 * removal or a duplicate MAC address is found.
-				 */
-				entry_success = free_entries;
-				vq->last_used_idx += entry_success;
-				rte_pktmbuf_free(m);
-				break;
-			}
-		}
-
-		virtio_tx_route(dev, m, mbuf_pool, (uint16_t)dev->device_fh);
-		vq->last_used_idx++;
-		entry_success++;
-		rte_pktmbuf_free(m);
-	}
-
-	rte_compiler_barrier();
-	vq->used->idx += entry_success;
-	/* Kick guest if required. */
-	if (!(vq->avail->flags & VRING_AVAIL_F_NO_INTERRUPT))
-		eventfd_write((int)vq->kickfd, 1);
-
-}
-
 /*
  * This function is called by each data core. It handles all RX/TX registered with the
  * core. For TX the specific lcore linked list is used. For RX, MAC addresses are compared
@@ -2035,6 +1140,7 @@ switch_worker(__attribute__((unused)) void *arg)
 {
 	struct rte_mempool *mbuf_pool = arg;
 	struct virtio_net *dev = NULL;
+	struct vhost_dev *vdev = NULL;
 	struct rte_mbuf *pkts_burst[MAX_PKT_BURST];
 	struct virtio_net_data_ll *dev_ll;
 	struct mbuf_table *tx_q;
@@ -2045,7 +1151,8 @@ switch_worker(__attribute__((unused)) void *arg)
 	const uint16_t lcore_id = rte_lcore_id();
 	const uint16_t num_cores = (uint16_t)rte_lcore_count();
 	uint16_t rx_count = 0;
-	uint32_t mergeable = 0;
+	uint16_t tx_count;
+	uint32_t retry = 0;
 
 	RTE_LOG(INFO, VHOST_DATA, "Procesing on Core %u started\n", lcore_id);
 	lcore_ll = lcore_info[lcore_id].lcore_ll;
@@ -2102,37 +1209,39 @@ switch_worker(__attribute__((unused)) void *arg)
 
 		while (dev_ll != NULL) {
 			/*get virtio device ID*/
-			dev = dev_ll->dev;
-			mergeable =
-				dev->features & (1 << VIRTIO_NET_F_MRG_RXBUF);
+			vdev = dev_ll->vdev;
+			dev = vdev->dev;
 
-			if (dev->remove) {
+			if (vdev->remove) {
 				dev_ll = dev_ll->next;
-				unlink_vmdq(dev);
-				dev->ready = DEVICE_SAFE_REMOVE;
+				unlink_vmdq(vdev);
+				vdev->ready = DEVICE_SAFE_REMOVE;
 				continue;
 			}
-			if (likely(dev->ready == DEVICE_RX)) {
+			if (likely(vdev->ready == DEVICE_RX)) {
 				/*Handle guest RX*/
 				rx_count = rte_eth_rx_burst(ports[0],
-					(uint16_t)dev->vmdq_rx_q, pkts_burst, MAX_PKT_BURST);
+					vdev->vmdq_rx_q, pkts_burst, MAX_PKT_BURST);
 
 				if (rx_count) {
-					if (likely(mergeable == 0))
-						ret_count =
-							virtio_dev_rx(dev,
-							pkts_burst, rx_count);
-					else
-						ret_count =
-							virtio_dev_merge_rx(dev,
-							pkts_burst, rx_count);
-
+					/*
+					* Retry is enabled and the queue is full then we wait and retry to avoid packet loss
+					* Here MAX_PKT_BURST must be less than virtio queue size
+					*/
+					if (enable_retry && unlikely(rx_count > rte_vring_available_entries(dev, VIRTIO_RXQ))) {
+						for (retry = 0; retry < burst_rx_retry_num; retry++) {
+							rte_delay_us(burst_rx_delay_time);
+							if (rx_count <= rte_vring_available_entries(dev, VIRTIO_RXQ))
+								break;
+						}
+					}
+					ret_count = rte_vhost_enqueue_burst(dev, VIRTIO_RXQ, pkts_burst, rx_count);
 					if (enable_stats) {
 						rte_atomic64_add(
-						&dev_statistics[dev_ll->dev->device_fh].rx_total_atomic,
+						&dev_statistics[dev_ll->vdev->dev->device_fh].rx_total_atomic,
 						rx_count);
 						rte_atomic64_add(
-						&dev_statistics[dev_ll->dev->device_fh].rx_atomic, ret_count);
+						&dev_statistics[dev_ll->vdev->dev->device_fh].rx_atomic, ret_count);
 					}
 					while (likely(rx_count)) {
 						rx_count--;
@@ -2142,12 +1251,18 @@ switch_worker(__attribute__((unused)) void *arg)
 				}
 			}
 
-			if (!dev->remove) {
-				/*Handle guest TX*/
-				if (likely(mergeable == 0))
-					virtio_dev_tx(dev, mbuf_pool);
-				else
-					virtio_dev_merge_tx(dev, mbuf_pool);
+			if (!vdev->remove) {
+				/* Handle guest TX*/
+				tx_count = rte_vhost_dequeue_burst(dev, VIRTIO_TXQ, mbuf_pool, pkts_burst, MAX_PKT_BURST);
+				/* If this is the first received packet we need to learn the MAC and setup VMDQ */
+				if (unlikely(vdev->ready == DEVICE_MAC_LEARNING) && tx_count) {
+					if (vdev->remove || (link_vmdq(vdev, pkts_burst[0]) == -1)) {
+						while (tx_count--)
+							rte_pktmbuf_free(pkts_burst[tx_count]);
+					}
+				}
+				while (tx_count)
+					virtio_tx_route(vdev, pkts_burst[--tx_count], mbuf_pool, (uint16_t)dev->device_fh);
 			}
 
 			/*move to the next device in the list*/
@@ -2264,12 +1379,13 @@ attach_rxmbuf_zcp(struct virtio_net *dev)
 	struct rte_mbuf *mbuf = NULL;
 	struct vpool *vpool;
 	hpa_type addr_type;
+	struct vhost_dev *vdev = (struct vhost_dev *)dev->priv;
 
-	vpool = &vpool_array[dev->vmdq_rx_q];
+	vpool = &vpool_array[vdev->vmdq_rx_q];
 	vq = dev->virtqueue[VIRTIO_RXQ];
 
 	do {
-		if (unlikely(get_available_ring_index_zcp(dev, &res_base_idx,
+		if (unlikely(get_available_ring_index_zcp(vdev->dev, &res_base_idx,
 				1) != 1))
 			return;
 		desc_idx = vq->avail->ring[(res_base_idx) & (vq->size - 1)];
@@ -2278,12 +1394,12 @@ attach_rxmbuf_zcp(struct virtio_net *dev)
 		if (desc->flags & VRING_DESC_F_NEXT) {
 			desc = &vq->desc[desc->next];
 			buff_addr = gpa_to_vva(dev, desc->addr);
-			phys_addr = gpa_to_hpa(dev, desc->addr, desc->len,
+			phys_addr = gpa_to_hpa(vdev, desc->addr, desc->len,
 					&addr_type);
 		} else {
 			buff_addr = gpa_to_vva(dev,
 					desc->addr + vq->vhost_hlen);
-			phys_addr = gpa_to_hpa(dev,
+			phys_addr = gpa_to_hpa(vdev,
 					desc->addr + vq->vhost_hlen,
 					desc->len, &addr_type);
 		}
@@ -2606,13 +1722,14 @@ virtio_tx_route_zcp(struct virtio_net *dev, struct rte_mbuf *m,
 	struct virtio_net_data_ll *dev_ll = ll_root_used;
 	struct ether_hdr *pkt_hdr = (struct ether_hdr *)m->pkt.data;
 	uint16_t vlan_tag = (uint16_t)vlan_tags[(uint16_t)dev->device_fh];
+	uint16_t vmdq_rx_q = ((struct vhost_dev *)dev->priv)->vmdq_rx_q;
 
 	/*Add packet to the port tx queue*/
-	tx_q = &tx_queue_zcp[(uint16_t)dev->vmdq_rx_q];
+	tx_q = &tx_queue_zcp[vmdq_rx_q];
 	len = tx_q->len;
 
 	/* Allocate an mbuf and populate the structure. */
-	vpool = &vpool_array[MAX_QUEUES + (uint16_t)dev->vmdq_rx_q];
+	vpool = &vpool_array[MAX_QUEUES + vmdq_rx_q];
 	rte_ring_sc_dequeue(vpool->ring, (void **)&mbuf);
 	if (unlikely(mbuf == NULL)) {
 		struct vhost_virtqueue *vq = dev->virtqueue[VIRTIO_TXQ];
@@ -2633,15 +1750,15 @@ virtio_tx_route_zcp(struct virtio_net *dev, struct rte_mbuf *m,
 		 */
 		vlan_tag = external_pkt_default_vlan_tag;
 		while (dev_ll != NULL) {
-			if (likely(dev_ll->dev->ready == DEVICE_RX) &&
+			if (likely(dev_ll->vdev->ready == DEVICE_RX) &&
 				ether_addr_cmp(&(pkt_hdr->d_addr),
-				&dev_ll->dev->mac_address)) {
+				&dev_ll->vdev->mac_address)) {
 
 				/*
 				 * Drop the packet if the TX packet is destined
 				 * for the TX device.
 				 */
-				if (unlikely(dev_ll->dev->device_fh
+				if (unlikely(dev_ll->vdev->dev->device_fh
 					== dev->device_fh)) {
 					LOG_DEBUG(VHOST_DATA,
 					"(%"PRIu64") TX: Source and destination"
@@ -2661,7 +1778,7 @@ virtio_tx_route_zcp(struct virtio_net *dev, struct rte_mbuf *m,
 				offset = 4;
 				vlan_tag =
 				(uint16_t)
-				vlan_tags[(uint16_t)dev_ll->dev->device_fh];
+				vlan_tags[(uint16_t)dev_ll->vdev->dev->device_fh];
 
 				LOG_DEBUG(VHOST_DATA,
 				"(%"PRIu64") TX: pkt to local VM device id:"
@@ -2751,6 +1868,7 @@ virtio_dev_tx_zcp(struct virtio_net *dev)
 	uint16_t avail_idx;
 	uint8_t need_copy = 0;
 	hpa_type addr_type;
+	struct vhost_dev *vdev = (struct vhost_dev *)dev->priv;
 
 	vq = dev->virtqueue[VIRTIO_TXQ];
 	avail_idx =  *((volatile uint16_t *)&vq->avail->idx);
@@ -2794,7 +1912,7 @@ virtio_dev_tx_zcp(struct virtio_net *dev)
 
 		/* Buffer address translation. */
 		buff_addr = gpa_to_vva(dev, desc->addr);
-		phys_addr = gpa_to_hpa(dev, desc->addr, desc->len, &addr_type);
+		phys_addr = gpa_to_hpa(vdev, desc->addr, desc->len, &addr_type);
 
 		if (likely(packet_success < (free_entries - 1)))
 			/* Prefetch descriptor index. */
@@ -2843,8 +1961,8 @@ virtio_dev_tx_zcp(struct virtio_net *dev)
 		 * If this is the first received packet we need to learn
 		 * the MAC and setup VMDQ
 		 */
-		if (unlikely(dev->ready == DEVICE_MAC_LEARNING)) {
-			if (dev->remove || (link_vmdq(dev, &m) == -1)) {
+		if (unlikely(vdev->ready == DEVICE_MAC_LEARNING)) {
+			if (vdev->remove || (link_vmdq(vdev, &m) == -1)) {
 				/*
 				 * Discard frame if device is scheduled for
 				 * removal or a duplicate MAC address is found.
@@ -2869,6 +1987,7 @@ static int
 switch_worker_zcp(__attribute__((unused)) void *arg)
 {
 	struct virtio_net *dev = NULL;
+	struct vhost_dev  *vdev = NULL;
 	struct rte_mbuf *pkts_burst[MAX_PKT_BURST];
 	struct virtio_net_data_ll *dev_ll;
 	struct mbuf_table *tx_q;
@@ -2897,12 +2016,13 @@ switch_worker_zcp(__attribute__((unused)) void *arg)
 			 * put back into vpool.ring.
 			 */
 			dev_ll = lcore_ll->ll_root_used;
-			while ((dev_ll != NULL) && (dev_ll->dev != NULL)) {
+			while ((dev_ll != NULL) && (dev_ll->vdev != NULL)) {
 				/* Get virtio device ID */
-				dev = dev_ll->dev;
+				vdev = dev_ll->vdev;
+				dev = vdev->dev;
 
-				if (likely(!dev->remove)) {
-					tx_q = &tx_queue_zcp[(uint16_t)dev->vmdq_rx_q];
+				if (likely(!vdev->remove)) {
+					tx_q = &tx_queue_zcp[(uint16_t)vdev->vmdq_rx_q];
 					if (tx_q->len) {
 						LOG_DEBUG(VHOST_DATA,
 						"TX queue drained after timeout"
@@ -2927,7 +2047,7 @@ switch_worker_zcp(__attribute__((unused)) void *arg)
 						tx_q->len = 0;
 
 						txmbuf_clean_zcp(dev,
-							&vpool_array[MAX_QUEUES+dev->vmdq_rx_q]);
+							&vpool_array[MAX_QUEUES + vdev->vmdq_rx_q]);
 					}
 				}
 				dev_ll = dev_ll->next;
@@ -2947,17 +2067,18 @@ switch_worker_zcp(__attribute__((unused)) void *arg)
 		/* Process devices */
 		dev_ll = lcore_ll->ll_root_used;
 
-		while ((dev_ll != NULL) && (dev_ll->dev != NULL)) {
-			dev = dev_ll->dev;
-			if (unlikely(dev->remove)) {
+		while ((dev_ll != NULL) && (dev_ll->vdev != NULL)) {
+			vdev = dev_ll->vdev;
+			dev  = vdev->dev;
+			if (unlikely(vdev->remove)) {
 				dev_ll = dev_ll->next;
-				unlink_vmdq(dev);
-				dev->ready = DEVICE_SAFE_REMOVE;
+				unlink_vmdq(vdev);
+				vdev->ready = DEVICE_SAFE_REMOVE;
 				continue;
 			}
 
-			if (likely(dev->ready == DEVICE_RX)) {
-				uint32_t index = dev->vmdq_rx_q;
+			if (likely(vdev->ready == DEVICE_RX)) {
+				uint32_t index = vdev->vmdq_rx_q;
 				uint16_t i;
 				count_in_ring
 				= rte_ring_count(vpool_array[index].ring);
@@ -2976,7 +2097,7 @@ switch_worker_zcp(__attribute__((unused)) void *arg)
 
 				/* Handle guest RX */
 				rx_count = rte_eth_rx_burst(ports[0],
-					(uint16_t)dev->vmdq_rx_q, pkts_burst,
+					vdev->vmdq_rx_q, pkts_burst,
 					MAX_PKT_BURST);
 
 				if (rx_count) {
@@ -2999,7 +2120,7 @@ switch_worker_zcp(__attribute__((unused)) void *arg)
 				}
 			}
 
-			if (likely(!dev->remove))
+			if (likely(!vdev->remove))
 				/* Handle guest TX */
 				virtio_dev_tx_zcp(dev);
 
@@ -3112,7 +2233,7 @@ alloc_data_ll(uint32_t size)
 	}
 
 	for (i = 0; i < size - 1; i++) {
-		ll_new[i].dev = NULL;
+		ll_new[i].vdev = NULL;
 		ll_new[i].next = &ll_new[i+1];
 	}
 	ll_new[i].next = NULL;
@@ -3152,42 +2273,32 @@ init_data_ll (void)
 }
 
 /*
- * Set virtqueue flags so that we do not receive interrupts.
- */
-static void
-set_irq_status (struct virtio_net *dev)
-{
-	dev->virtqueue[VIRTIO_RXQ]->used->flags = VRING_USED_F_NO_NOTIFY;
-	dev->virtqueue[VIRTIO_TXQ]->used->flags = VRING_USED_F_NO_NOTIFY;
-}
-
-/*
  * Remove a device from the specific data core linked list and from the main linked list. Synchonization
  * occurs through the use of the lcore dev_removal_flag. Device is made volatile here to avoid re-ordering
  * of dev->remove=1 which can cause an infinite loop in the rte_pause loop.
  */
 static void
-destroy_device (volatile struct virtio_net *dev)
+destroy_device(struct virtio_net *dev)
 {
 	struct virtio_net_data_ll *ll_lcore_dev_cur;
 	struct virtio_net_data_ll *ll_main_dev_cur;
 	struct virtio_net_data_ll *ll_lcore_dev_last = NULL;
 	struct virtio_net_data_ll *ll_main_dev_last = NULL;
+	struct vhost_dev *vdev;
 	int lcore;
 
 	dev->flags &= ~VIRTIO_DEV_RUNNING;
 
+	vdev = (struct vhost_dev *)dev->priv;
 	/*set the remove flag. */
-	dev->remove = 1;
-
-	while(dev->ready != DEVICE_SAFE_REMOVE) {
+	vdev->remove = 1;
+	while (vdev->ready != DEVICE_SAFE_REMOVE)
 		rte_pause();
-	}
 
 	/* Search for entry to be removed from lcore ll */
-	ll_lcore_dev_cur = lcore_info[dev->coreid].lcore_ll->ll_root_used;
+	ll_lcore_dev_cur = lcore_info[vdev->coreid].lcore_ll->ll_root_used;
 	while (ll_lcore_dev_cur != NULL) {
-		if (ll_lcore_dev_cur->dev == dev) {
+		if (ll_lcore_dev_cur->vdev == vdev) {
 			break;
 		} else {
 			ll_lcore_dev_last = ll_lcore_dev_cur;
@@ -3206,7 +2317,7 @@ destroy_device (volatile struct virtio_net *dev)
 	ll_main_dev_cur = ll_root_used;
 	ll_main_dev_last = NULL;
 	while (ll_main_dev_cur != NULL) {
-		if (ll_main_dev_cur->dev == dev) {
+		if (ll_main_dev_cur->vdev == vdev) {
 			break;
 		} else {
 			ll_main_dev_last = ll_main_dev_cur;
@@ -3215,7 +2326,7 @@ destroy_device (volatile struct virtio_net *dev)
 	}
 
 	/* Remove entries from the lcore and main ll. */
-	rm_data_ll_entry(&lcore_info[ll_lcore_dev_cur->dev->coreid].lcore_ll->ll_root_used, ll_lcore_dev_cur, ll_lcore_dev_last);
+	rm_data_ll_entry(&lcore_info[vdev->coreid].lcore_ll->ll_root_used, ll_lcore_dev_cur, ll_lcore_dev_last);
 	rm_data_ll_entry(&ll_root_used, ll_main_dev_cur, ll_main_dev_last);
 
 	/* Set the dev_removal_flag on each lcore. */
@@ -3235,19 +2346,19 @@ destroy_device (volatile struct virtio_net *dev)
 	}
 
 	/* Add the entries back to the lcore and main free ll.*/
-	put_data_ll_free_entry(&lcore_info[ll_lcore_dev_cur->dev->coreid].lcore_ll->ll_root_free, ll_lcore_dev_cur);
+	put_data_ll_free_entry(&lcore_info[vdev->coreid].lcore_ll->ll_root_free, ll_lcore_dev_cur);
 	put_data_ll_free_entry(&ll_root_free, ll_main_dev_cur);
 
 	/* Decrement number of device on the lcore. */
-	lcore_info[ll_lcore_dev_cur->dev->coreid].lcore_ll->device_num--;
+	lcore_info[vdev->coreid].lcore_ll->device_num--;
 
 	RTE_LOG(INFO, VHOST_DATA, "(%"PRIu64") Device has been removed from data core\n", dev->device_fh);
 
 	if (zero_copy) {
-		struct vpool *vpool = &vpool_array[dev->vmdq_rx_q];
+		struct vpool *vpool = &vpool_array[vdev->vmdq_rx_q];
 
 		/* Stop the RX queue. */
-		if (rte_eth_dev_rx_queue_stop(ports[0], dev->vmdq_rx_q) != 0) {
+		if (rte_eth_dev_rx_queue_stop(ports[0], vdev->vmdq_rx_q) != 0) {
 			LOG_DEBUG(VHOST_CONFIG,
 				"(%"PRIu64") In destroy_device: Failed to stop "
 				"rx queue:%d\n",
@@ -3263,24 +2374,173 @@ destroy_device (volatile struct virtio_net *dev)
 		mbuf_destroy_zcp(vpool);
 
 		/* Stop the TX queue. */
-		if (rte_eth_dev_tx_queue_stop(ports[0], dev->vmdq_rx_q) != 0) {
+		if (rte_eth_dev_tx_queue_stop(ports[0], vdev->vmdq_rx_q) != 0) {
 			LOG_DEBUG(VHOST_CONFIG,
 				"(%"PRIu64") In destroy_device: Failed to "
 				"stop tx queue:%d\n",
 				dev->device_fh, dev->vmdq_rx_q);
 		}
 
-		vpool = &vpool_array[dev->vmdq_rx_q + MAX_QUEUES];
+		vpool = &vpool_array[vdev->vmdq_rx_q + MAX_QUEUES];
 
 		LOG_DEBUG(VHOST_CONFIG,
 			"(%"PRIu64") destroy_device: Start put mbuf in mempool "
 			"back to ring for TX queue: %d, dev:(%"PRIu64")\n",
-			dev->device_fh, (dev->vmdq_rx_q + MAX_QUEUES),
+			dev->device_fh, (vdev->vmdq_rx_q + MAX_QUEUES),
 			dev->device_fh);
 
 		mbuf_destroy_zcp(vpool);
+		rte_free(vdev->regions_hpa);
+	}
+	rte_free(vdev);
+
+}
+
+/*
+ * Calculate the region count of physical continous regions for one particular
+ * region of whose vhost virtual address is continous. The particular region
+ * start from vva_start, with size of 'size' in argument.
+ */
+static uint32_t
+check_hpa_regions(uint64_t vva_start, uint64_t size)
+{
+	uint32_t i, nregions = 0, page_size = getpagesize();
+	uint64_t cur_phys_addr = 0, next_phys_addr = 0;
+	if (vva_start % page_size) {
+		LOG_DEBUG(VHOST_CONFIG,
+			"in check_countinous: vva start(%p) mod page_size(%d) "
+			"has remainder\n",
+			(void *)(uintptr_t)vva_start, page_size);
+		return 0;
+	}
+	if (size % page_size) {
+		LOG_DEBUG(VHOST_CONFIG,
+			"in check_countinous: "
+			"size((%"PRIu64")) mod page_size(%d) has remainder\n",
+			size, page_size);
+		return 0;
+	}
+	for (i = 0; i < size - page_size; i = i + page_size) {
+		cur_phys_addr
+			= rte_mem_virt2phy((void *)(uintptr_t)(vva_start + i));
+		next_phys_addr = rte_mem_virt2phy(
+			(void *)(uintptr_t)(vva_start + i + page_size));
+		if ((cur_phys_addr + page_size) != next_phys_addr) {
+			++nregions;
+			LOG_DEBUG(VHOST_CONFIG,
+				"in check_continuous: hva addr:(%p) is not "
+				"continuous with hva addr:(%p), diff:%d\n",
+				(void *)(uintptr_t)(vva_start + (uint64_t)i),
+				(void *)(uintptr_t)(vva_start + (uint64_t)i
+				+ page_size), page_size);
+			LOG_DEBUG(VHOST_CONFIG,
+				"in check_continuous: hpa addr:(%p) is not "
+				"continuous with hpa addr:(%p), "
+				"diff:(%"PRIu64")\n",
+				(void *)(uintptr_t)cur_phys_addr,
+				(void *)(uintptr_t)next_phys_addr,
+				(next_phys_addr-cur_phys_addr));
+		}
 	}
+	return nregions;
+}
 
+/*
+ * Divide each region whose vhost virtual address is continous into a few
+ * sub-regions, make sure the physical address within each sub-region are
+ * continous. And fill offset(to GPA) and size etc. information of each
+ * sub-region into regions_hpa.
+ */
+static uint32_t
+fill_hpa_memory_regions(struct virtio_memory_regions_hpa *mem_region_hpa, struct virtio_memory *virtio_memory)
+{
+	uint32_t regionidx, regionidx_hpa = 0, i, k, page_size = getpagesize();
+	uint64_t cur_phys_addr = 0, next_phys_addr = 0, vva_start;
+
+	if (mem_region_hpa == NULL)
+		return 0;
+
+	for (regionidx = 0; regionidx < virtio_memory->nregions; regionidx++) {
+		vva_start = virtio_memory->regions[regionidx].guest_phys_address +
+			virtio_memory->regions[regionidx].address_offset;
+		mem_region_hpa[regionidx_hpa].guest_phys_address
+			= virtio_memory->regions[regionidx].guest_phys_address;
+		mem_region_hpa[regionidx_hpa].host_phys_addr_offset =
+			rte_mem_virt2phy((void *)(uintptr_t)(vva_start)) -
+			mem_region_hpa[regionidx_hpa].guest_phys_address;
+		LOG_DEBUG(VHOST_CONFIG,
+			"in fill_hpa_regions: guest phys addr start[%d]:(%p)\n",
+			regionidx_hpa,
+			(void *)(uintptr_t)
+			(mem_region_hpa[regionidx_hpa].guest_phys_address));
+		LOG_DEBUG(VHOST_CONFIG,
+			"in fill_hpa_regions: host  phys addr start[%d]:(%p)\n",
+			regionidx_hpa,
+			(void *)(uintptr_t)
+			(mem_region_hpa[regionidx_hpa].host_phys_addr_offset));
+		for (i = 0, k = 0;
+			i < virtio_memory->regions[regionidx].memory_size -
+				page_size;
+			i += page_size) {
+			cur_phys_addr = rte_mem_virt2phy(
+					(void *)(uintptr_t)(vva_start + i));
+			next_phys_addr = rte_mem_virt2phy(
+					(void *)(uintptr_t)(vva_start +
+					i + page_size));
+			if ((cur_phys_addr + page_size) != next_phys_addr) {
+				mem_region_hpa[regionidx_hpa].guest_phys_address_end =
+					mem_region_hpa[regionidx_hpa].guest_phys_address +
+					k + page_size;
+				mem_region_hpa[regionidx_hpa].memory_size
+					= k + page_size;
+				LOG_DEBUG(VHOST_CONFIG, "in fill_hpa_regions: guest "
+					"phys addr end  [%d]:(%p)\n",
+					regionidx_hpa,
+					(void *)(uintptr_t)
+					(mem_region_hpa[regionidx_hpa].guest_phys_address_end));
+				LOG_DEBUG(VHOST_CONFIG,
+					"in fill_hpa_regions: guest phys addr "
+					"size [%d]:(%p)\n",
+					regionidx_hpa,
+					(void *)(uintptr_t)
+					(mem_region_hpa[regionidx_hpa].memory_size));
+				mem_region_hpa[regionidx_hpa + 1].guest_phys_address
+					= mem_region_hpa[regionidx_hpa].guest_phys_address_end;
+				++regionidx_hpa;
+				mem_region_hpa[regionidx_hpa].host_phys_addr_offset =
+					next_phys_addr -
+					mem_region_hpa[regionidx_hpa].guest_phys_address;
+				LOG_DEBUG(VHOST_CONFIG, "in fill_hpa_regions: guest"
+					" phys addr start[%d]:(%p)\n",
+					regionidx_hpa,
+					(void *)(uintptr_t)
+					(mem_region_hpa[regionidx_hpa].guest_phys_address));
+				LOG_DEBUG(VHOST_CONFIG,
+					"in fill_hpa_regions: host  phys addr "
+					"start[%d]:(%p)\n",
+					regionidx_hpa,
+					(void *)(uintptr_t)
+					(mem_region_hpa[regionidx_hpa].host_phys_addr_offset));
+				k = 0;
+			} else {
+				k += page_size;
+			}
+		}
+		mem_region_hpa[regionidx_hpa].guest_phys_address_end
+			= mem_region_hpa[regionidx_hpa].guest_phys_address
+			+ k + page_size;
+		mem_region_hpa[regionidx_hpa].memory_size = k + page_size;
+		LOG_DEBUG(VHOST_CONFIG, "in fill_hpa_regions: guest phys addr end  "
+			"[%d]:(%p)\n", regionidx_hpa,
+			(void *)(uintptr_t)
+			(mem_region_hpa[regionidx_hpa].guest_phys_address_end));
+		LOG_DEBUG(VHOST_CONFIG, "in fill_hpa_regions: guest phys addr size "
+			"[%d]:(%p)\n", regionidx_hpa,
+			(void *)(uintptr_t)
+			(mem_region_hpa[regionidx_hpa].memory_size));
+		++regionidx_hpa;
+	}
+	return regionidx_hpa;
 }
 
 /*
@@ -3293,6 +2553,52 @@ new_device (struct virtio_net *dev)
 	struct virtio_net_data_ll *ll_dev;
 	int lcore, core_add = 0;
 	uint32_t device_num_min = num_devices;
+	struct vhost_dev *vdev;
+	uint32_t regionidx;
+
+	vdev = rte_zmalloc("vhost device", sizeof(*vdev), CACHE_LINE_SIZE);
+	if (vdev == NULL) {
+		RTE_LOG(INFO, VHOST_DATA, "(%"PRIu64") Couldn't allocate memory for vhost dev\n",
+			dev->device_fh);
+		return -1;
+	}
+	vdev->dev = dev;
+	dev->priv = vdev;
+
+	if (zero_copy) {
+		vdev->nregions_hpa = dev->mem->nregions;
+		for (regionidx = 0; regionidx < dev->mem->nregions; regionidx++) {
+			vdev->nregions_hpa
+				+= check_hpa_regions(
+					dev->mem->regions[regionidx].guest_phys_address
+					+ dev->mem->regions[regionidx].address_offset,
+					dev->mem->regions[regionidx].memory_size);
+
+		}
+
+		vdev->regions_hpa = (struct virtio_memory_regions_hpa *) rte_zmalloc("vhost hpa region",
+			sizeof(struct virtio_memory_regions_hpa) * vdev->nregions_hpa,
+			CACHE_LINE_SIZE);
+		if (vdev->regions_hpa == NULL) {
+			RTE_LOG(ERR, VHOST_CONFIG, "Cannot allocate memory for hpa region\n");
+			rte_free(vdev);
+			return -1;
+		}
+
+
+		if (fill_hpa_memory_regions(
+			vdev->regions_hpa, dev->mem
+			) != vdev->nregions_hpa) {
+
+			RTE_LOG(ERR, VHOST_CONFIG,
+				"hpa memory regions number mismatch: "
+				"[%d]\n", vdev->nregions_hpa);
+			rte_free(vdev->regions_hpa);
+			rte_free(vdev);
+			return -1;
+		}
+	}
+
 
 	/* Add device to main ll */
 	ll_dev = get_data_ll_free_entry(&ll_root_free);
@@ -3300,15 +2606,18 @@ new_device (struct virtio_net *dev)
 		RTE_LOG(INFO, VHOST_DATA, "(%"PRIu64") No free entry found in linked list. Device limit "
 			"of %d devices per core has been reached\n",
 			dev->device_fh, num_devices);
+		if (vdev->regions_hpa)
+			rte_free(vdev->regions_hpa);
+		rte_free(vdev);
 		return -1;
 	}
-	ll_dev->dev = dev;
+	ll_dev->vdev = vdev;
 	add_data_ll_entry(&ll_root_used, ll_dev);
-	ll_dev->dev->vmdq_rx_q
-		= ll_dev->dev->device_fh * (num_queues / num_devices);
+	vdev->vmdq_rx_q
+		= dev->device_fh *  (num_queues / num_devices);
 
 	if (zero_copy) {
-		uint32_t index = ll_dev->dev->vmdq_rx_q;
+		uint32_t index = vdev->vmdq_rx_q;
 		uint32_t count_in_ring, i;
 		struct mbuf_table *tx_q;
 
@@ -3339,47 +2648,51 @@ new_device (struct virtio_net *dev)
 			dev->device_fh,
 			rte_ring_count(vpool_array[index].ring));
 
-		tx_q = &tx_queue_zcp[(uint16_t)dev->vmdq_rx_q];
-		tx_q->txq_id = dev->vmdq_rx_q;
+		tx_q = &tx_queue_zcp[(uint16_t)vdev->vmdq_rx_q];
+		tx_q->txq_id = vdev->vmdq_rx_q;
 
-		if (rte_eth_dev_tx_queue_start(ports[0], dev->vmdq_rx_q) != 0) {
-			struct vpool *vpool = &vpool_array[dev->vmdq_rx_q];
+		if (rte_eth_dev_tx_queue_start(ports[0], vdev->vmdq_rx_q) != 0) {
+			struct vpool *vpool = &vpool_array[vdev->vmdq_rx_q];
 
 			LOG_DEBUG(VHOST_CONFIG,
 				"(%"PRIu64") In new_device: Failed to start "
 				"tx queue:%d\n",
-				dev->device_fh, dev->vmdq_rx_q);
+				dev->device_fh, vdev->vmdq_rx_q);
 
 			mbuf_destroy_zcp(vpool);
+			rte_free(vdev->regions_hpa);
+			rte_free(vdev);
 			return -1;
 		}
 
-		if (rte_eth_dev_rx_queue_start(ports[0], dev->vmdq_rx_q) != 0) {
-			struct vpool *vpool = &vpool_array[dev->vmdq_rx_q];
+		if (rte_eth_dev_rx_queue_start(ports[0], vdev->vmdq_rx_q) != 0) {
+			struct vpool *vpool = &vpool_array[vdev->vmdq_rx_q];
 
 			LOG_DEBUG(VHOST_CONFIG,
 				"(%"PRIu64") In new_device: Failed to start "
 				"rx queue:%d\n",
-				dev->device_fh, dev->vmdq_rx_q);
+				dev->device_fh, vdev->vmdq_rx_q);
 
 			/* Stop the TX queue. */
 			if (rte_eth_dev_tx_queue_stop(ports[0],
-				dev->vmdq_rx_q) != 0) {
+				vdev->vmdq_rx_q) != 0) {
 				LOG_DEBUG(VHOST_CONFIG,
 					"(%"PRIu64") In new_device: Failed to "
 					"stop tx queue:%d\n",
-					dev->device_fh, dev->vmdq_rx_q);
+					dev->device_fh, vmdq_rx_q);
 			}
 
 			mbuf_destroy_zcp(vpool);
+			rte_free(vdev->regions_hpa);
+			rte_free(vdev);
 			return -1;
 		}
 
 	}
 
 	/*reset ready flag*/
-	dev->ready = DEVICE_MAC_LEARNING;
-	dev->remove = 0;
+	vdev->ready = DEVICE_MAC_LEARNING;
+	vdev->remove = 0;
 
 	/* Find a suitable lcore to add the device. */
 	RTE_LCORE_FOREACH_SLAVE(lcore) {
@@ -3389,26 +2702,33 @@ new_device (struct virtio_net *dev)
 		}
 	}
 	/* Add device to lcore ll */
-	ll_dev->dev->coreid = core_add;
-	ll_dev = get_data_ll_free_entry(&lcore_info[ll_dev->dev->coreid].lcore_ll->ll_root_free);
+	ll_dev = get_data_ll_free_entry(&lcore_info[core_add].lcore_ll->ll_root_free);
 	if (ll_dev == NULL) {
 		RTE_LOG(INFO, VHOST_DATA, "(%"PRIu64") Failed to add device to data core\n", dev->device_fh);
-		dev->ready = DEVICE_SAFE_REMOVE;
+		vdev->ready = DEVICE_SAFE_REMOVE;
 		destroy_device(dev);
+		if (vdev->regions_hpa)
+			rte_free(vdev->regions_hpa);
+		rte_free(vdev);
 		return -1;
 	}
-	ll_dev->dev = dev;
-	add_data_ll_entry(&lcore_info[ll_dev->dev->coreid].lcore_ll->ll_root_used, ll_dev);
+	ll_dev->vdev = vdev;
+	vdev->coreid = core_add;
+
+
+
+	add_data_ll_entry(&lcore_info[vdev->coreid].lcore_ll->ll_root_used, ll_dev);
 
 	/* Initialize device stats */
 	memset(&dev_statistics[dev->device_fh], 0, sizeof(struct device_statistics));
 
 	/* Disable notifications. */
-	set_irq_status(dev);
-	lcore_info[ll_dev->dev->coreid].lcore_ll->device_num++;
+	rte_vhost_enable_guest_notification(dev, VIRTIO_RXQ, 0);
+	rte_vhost_enable_guest_notification(dev, VIRTIO_TXQ, 0);
+	lcore_info[vdev->coreid].lcore_ll->device_num++;
 	dev->flags |= VIRTIO_DEV_RUNNING;
 
-	RTE_LOG(INFO, VHOST_DATA, "(%"PRIu64") Device has been added to data core %d\n", dev->device_fh, dev->coreid);
+	RTE_LOG(INFO, VHOST_DATA, "(%"PRIu64") Device has been added to data core %d\n", dev->device_fh, vdev->coreid);
 
 	return 0;
 }
@@ -3447,7 +2767,7 @@ print_stats(void)
 
 		dev_ll = ll_root_used;
 		while (dev_ll != NULL) {
-			device_fh = (uint32_t)dev_ll->dev->device_fh;
+			device_fh = (uint32_t)dev_ll->vdev->dev->device_fh;
 			tx_total = dev_statistics[device_fh].tx_total;
 			tx = dev_statistics[device_fh].tx;
 			tx_dropped = tx_total - tx;
@@ -3707,15 +3027,18 @@ MAIN(int argc, char *argv[])
 				lcore_id);
 	}
 
+	if (mergeable == 0)
+		rte_vhost_feature_disable(1ULL << VIRTIO_NET_F_MRG_RXBUF);
+
 	/* Register CUSE device to handle IOCTLs. */
-	ret = register_cuse_device((char*)&dev_basename, dev_index, get_virtio_net_callbacks());
+	ret = rte_vhost_driver_register((char *)&dev_basename);
 	if (ret != 0)
 		rte_exit(EXIT_FAILURE,"CUSE device setup failure.\n");
 
-	init_virtio_net(&virtio_net_device_ops);
+	rte_vhost_driver_callback_register(&virtio_net_device_ops);
 
 	/* Start CUSE session. */
-	start_cuse_session_loop();
+	rte_vhost_driver_session_start();
 	return 0;
 
 }
diff --git a/examples/vhost/main.h b/examples/vhost/main.h
index c15d938..02e991d 100644
--- a/examples/vhost/main.h
+++ b/examples/vhost/main.h
@@ -57,13 +57,50 @@
 #define RTE_LOGTYPE_VHOST_DATA   RTE_LOGTYPE_USER2
 #define RTE_LOGTYPE_VHOST_PORT   RTE_LOGTYPE_USER3
 
-/*
+/**
+ * Information relating to memory regions including offsets to
+ * addresses in host physical space.
+ */
+struct virtio_memory_regions_hpa {
+	/**< Base guest physical address of region. */
+	uint64_t    guest_phys_address;
+	/**< End guest physical address of region. */
+	uint64_t    guest_phys_address_end;
+	/**< Size of region. */
+	uint64_t    memory_size;
+	/**< Offset of region for gpa to hpa translation. */
+	uint64_t    host_phys_addr_offset;
+};
+
+/**
  * Device linked list structure for data path.
  */
-struct virtio_net_data_ll
-{
-	struct virtio_net			*dev;	/* Pointer to device created by configuration core. */
-	struct virtio_net_data_ll	*next;  /* Pointer to next device in linked list. */
+struct vhost_dev {
+	/**< Pointer to device created by vhost lib. */
+	struct virtio_net      *dev;
+	/**< Number of memory regions for gpa to hpa translation. */
+	uint32_t nregions_hpa;
+	/**< Memory region information for gpa to hpa translation. */
+	struct virtio_memory_regions_hpa *regions_hpa;
+	/**< Device MAC address (Obtained on first TX packet). */
+	struct ether_addr mac_address;
+	/**< RX VMDQ queue number. */
+	uint16_t vmdq_rx_q;
+	/**< Vlan tag assigned to the pool */
+	uint32_t vlan_tag;
+	/**< Data core that the device is added to. */
+	uint16_t coreid;
+	/**< A device is set as ready if the MAC address has been set. */
+	volatile uint8_t ready;
+	/**< Device is marked for removal from the data core. */
+	volatile uint8_t remove;
+} __rte_cache_aligned;
+
+struct virtio_net_data_ll {
+	/* Pointer to device created by configuration core. */
+	struct vhost_dev		*vdev;
+	/* Pointer to next device in linked list. */
+	struct virtio_net_data_ll	*next;
 };
 
 /*
-- 
1.8.1.4

^ permalink raw reply	[flat|nested] 23+ messages in thread

* [dpdk-dev] [PATCH v5 10/11] examples/vhost: merge oliver's mbuf changes to vhost example
  2014-09-26  9:45 [dpdk-dev] [PATCH v5 00/11] user space vhost library and vhost example Huawei Xie
                   ` (8 preceding siblings ...)
  2014-09-26  9:45 ` [dpdk-dev] [PATCH v5 09/11] examples/vhost: vhost example based on vhost lib API Huawei Xie
@ 2014-09-26  9:45 ` Huawei Xie
  2014-09-26  9:45 ` [dpdk-dev] [PATCH v5 11/11] examples/vhost: add vhost example Makefile Huawei Xie
  10 siblings, 0 replies; 23+ messages in thread
From: Huawei Xie @ 2014-09-26  9:45 UTC (permalink / raw)
  To: dev

The mbuf changes include:
1. flattened structure vlan_macip
2. removed rte_pktmbuf structure.
3. mbuf data pointer replaced by an offset

Other changes include:
1. fix sg mbuf xmit in virtio_tx_route
2. rename RTE_MBUF_SCATTER_GATHER to RTE_MBUF_REFCNT
3. add one TODO and FIXME 

Signed-off-by: Huawei Xie <huawei.xie@intel.com>
---
 examples/vhost/main.c | 57 ++++++++++++++++++++++++++-------------------------
 1 file changed, 29 insertions(+), 28 deletions(-)

diff --git a/examples/vhost/main.c b/examples/vhost/main.c
index 3834af4..6569188 100644
--- a/examples/vhost/main.c
+++ b/examples/vhost/main.c
@@ -716,10 +716,10 @@ us_vhost_parse_args(int argc, char **argv)
 					zero_copy = ret;
 
 				if (zero_copy) {
-#ifdef RTE_MBUF_SCATTER_GATHER
+#ifdef RTE_MBUF_REFCNT
 					RTE_LOG(ERR, VHOST_CONFIG, "Before running "
 					"zero copy vhost APP, please "
-					"disable RTE_MBUF_SCATTER_GATHER\n"
+					"disable RTE_MBUF_REFCNT\n"
 					"in config file and then rebuild DPDK "
 					"core lib!\n"
 					"Otherwise please disable zero copy "
@@ -906,7 +906,7 @@ link_vmdq(struct vhost_dev *vdev, struct rte_mbuf *m)
 	int i, ret;
 
 	/* Learn MAC address of guest device from packet */
-	pkt_hdr = (struct ether_hdr *)m->pkt.data;
+	pkt_hdr = rte_pktmbuf_mtod(m, struct ether_hdr *);
 
 	dev_ll = ll_root_used;
 
@@ -995,7 +995,7 @@ virtio_tx_local(struct vhost_dev *vdev, struct rte_mbuf *m)
 	struct virtio_net *dev = vdev->dev;
 	struct virtio_net *tdev; /* destination virito device */
 
-	pkt_hdr = (struct ether_hdr *)m->pkt.data;
+	pkt_hdr = rte_pktmbuf_mtod(m, struct ether_hdr *);
 
 	/*get the used devices list*/
 	dev_ll = ll_root_used;
@@ -1052,7 +1052,7 @@ virtio_tx_route(struct vhost_dev *vdev, struct rte_mbuf *m, struct rte_mempool *
 	unsigned len, ret, offset = 0;
 	const uint16_t lcore_id = rte_lcore_id();
 	struct virtio_net_data_ll *dev_ll = ll_root_used;
-	struct ether_hdr *pkt_hdr = (struct ether_hdr *)m->pkt.data;
+	struct ether_hdr *pkt_hdr = rte_pktmbuf_mtod(m, struct ether_hdr *);
 	struct virtio_net *dev = vdev->dev;
 
 	/*heck if destination is local VM*/
@@ -1104,8 +1104,8 @@ virtio_tx_route(struct vhost_dev *vdev, struct rte_mbuf *m, struct rte_mempool *
 
 	m->ol_flags = PKT_TX_VLAN_PKT;
 	/*FIXME: offset*/
-	m->pkt.data_len += offset;
-	m->pkt.vlan_macip.f.vlan_tci = vlan_tag;
+	m->data_len += offset;
+	m->vlan_tci = vlan_tag;
 
 	tx_q->m_table[len] = m;
 	len++;
@@ -1449,9 +1449,9 @@ attach_rxmbuf_zcp(struct virtio_net *dev)
 	}
 
 	mbuf->buf_addr = (void *)(uintptr_t)(buff_addr - RTE_PKTMBUF_HEADROOM);
-	mbuf->pkt.data = (void *)(uintptr_t)(buff_addr);
+	mbuf->data_off = RTE_PKTMBUF_HEADROOM;
 	mbuf->buf_physaddr = phys_addr - RTE_PKTMBUF_HEADROOM;
-	mbuf->pkt.data_len = desc->len;
+	mbuf->data_len = desc->len;
 	MBUF_HEADROOM_UINT32(mbuf) = (uint32_t)desc_idx;
 
 	LOG_DEBUG(VHOST_DATA,
@@ -1486,9 +1486,9 @@ static inline void pktmbuf_detach_zcp(struct rte_mbuf *m)
 
 	buf_ofs = (RTE_PKTMBUF_HEADROOM <= m->buf_len) ?
 			RTE_PKTMBUF_HEADROOM : m->buf_len;
-	m->pkt.data = (char *) m->buf_addr + buf_ofs;
+	m->data_off = buf_ofs;
 
-	m->pkt.data_len = 0;
+	m->data_len = 0;
 }
 
 /*
@@ -1720,7 +1720,7 @@ virtio_tx_route_zcp(struct virtio_net *dev, struct rte_mbuf *m,
 	unsigned len, ret, offset = 0;
 	struct vpool *vpool;
 	struct virtio_net_data_ll *dev_ll = ll_root_used;
-	struct ether_hdr *pkt_hdr = (struct ether_hdr *)m->pkt.data;
+	struct ether_hdr *pkt_hdr = rte_pktmbuf_mtod(m, struct ether_hdr *);
 	uint16_t vlan_tag = (uint16_t)vlan_tags[(uint16_t)dev->device_fh];
 	uint16_t vmdq_rx_q = ((struct vhost_dev *)dev->priv)->vmdq_rx_q;
 
@@ -1792,24 +1792,25 @@ virtio_tx_route_zcp(struct virtio_net *dev, struct rte_mbuf *m,
 		}
 	}
 
-	mbuf->pkt.nb_segs = m->pkt.nb_segs;
-	mbuf->pkt.next = m->pkt.next;
-	mbuf->pkt.data_len = m->pkt.data_len + offset;
-	mbuf->pkt.pkt_len = mbuf->pkt.data_len;
+	mbuf->nb_segs = m->nb_segs;
+	mbuf->next = m->next;
+	mbuf->data_len = m->data_len + offset;
+	mbuf->pkt_len = mbuf->data_len;
 	if (unlikely(need_copy)) {
 		/* Copy the packet contents to the mbuf. */
-		rte_memcpy((void *)((uint8_t *)mbuf->pkt.data),
-			(const void *) ((uint8_t *)m->pkt.data),
-			m->pkt.data_len);
+		rte_memcpy(rte_pktmbuf_mtod(mbuf, void *),
+			rte_pktmbuf_mtod(m, const void *),
+			m->data_len);
 	} else {
-		mbuf->pkt.data = m->pkt.data;
+		/* TODO verification */
+		mbuf->data_off = m->data_off;
 		mbuf->buf_physaddr = m->buf_physaddr;
 		mbuf->buf_addr = m->buf_addr;
 	}
 	mbuf->ol_flags = PKT_TX_VLAN_PKT;
-	mbuf->pkt.vlan_macip.f.vlan_tci = vlan_tag;
-	mbuf->pkt.vlan_macip.f.l2_len = sizeof(struct ether_hdr);
-	mbuf->pkt.vlan_macip.f.l3_len = sizeof(struct ipv4_hdr);
+	mbuf->vlan_tci = vlan_tag;
+	mbuf->l2_len = sizeof(struct ether_hdr);
+	mbuf->l3_len = sizeof(struct ipv4_hdr);
 	MBUF_HEADROOM_UINT32(mbuf) = (uint32_t)desc_idx;
 
 	tx_q->m_table[len] = mbuf;
@@ -1934,11 +1935,11 @@ virtio_dev_tx_zcp(struct virtio_net *dev)
 		 * Setup dummy mbuf. This is copied to a real mbuf if
 		 * transmitted out the physical port.
 		 */
-		m.pkt.data_len = desc->len;
-		m.pkt.nb_segs = 1;
-		m.pkt.next = NULL;
-		m.pkt.data = (void *)(uintptr_t)buff_addr;
-		m.buf_addr = m.pkt.data;
+		m.data_len = desc->len;
+		m.nb_segs = 1;
+		m.next = NULL;
+		m.data_off = 0;
+		m.buf_addr = (void *)(uintptr_t)buff_addr;
 		m.buf_physaddr = phys_addr;
 
 		/*
-- 
1.8.1.4

^ permalink raw reply	[flat|nested] 23+ messages in thread

* [dpdk-dev] [PATCH v5 11/11] examples/vhost: add vhost example Makefile
  2014-09-26  9:45 [dpdk-dev] [PATCH v5 00/11] user space vhost library and vhost example Huawei Xie
                   ` (9 preceding siblings ...)
  2014-09-26  9:45 ` [dpdk-dev] [PATCH v5 10/11] examples/vhost: merge oliver's mbuf changes to vhost example Huawei Xie
@ 2014-09-26  9:45 ` Huawei Xie
  10 siblings, 0 replies; 23+ messages in thread
From: Huawei Xie @ 2014-09-26  9:45 UTC (permalink / raw)
  To: dev

Signed-off-by: Huawei Xie <huawei.xie@intel.com>
---
 examples/vhost/Makefile | 52 +++++++++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 52 insertions(+)
 create mode 100644 examples/vhost/Makefile

diff --git a/examples/vhost/Makefile b/examples/vhost/Makefile
new file mode 100644
index 0000000..a4d4fb0
--- /dev/null
+++ b/examples/vhost/Makefile
@@ -0,0 +1,52 @@
+#   BSD LICENSE
+#
+#   Copyright(c) 2010-2014 Intel Corporation. All rights reserved.
+#   All rights reserved.
+#
+#   Redistribution and use in source and binary forms, with or without
+#   modification, are permitted provided that the following conditions
+#   are met:
+#
+#     * Redistributions of source code must retain the above copyright
+#       notice, this list of conditions and the following disclaimer.
+#     * Redistributions in binary form must reproduce the above copyright
+#       notice, this list of conditions and the following disclaimer in
+#       the documentation and/or other materials provided with the
+#       distribution.
+#     * Neither the name of Intel Corporation nor the names of its
+#       contributors may be used to endorse or promote products derived
+#       from this software without specific prior written permission.
+#
+#   THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+#   "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+#   LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+#   A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+#   OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+#   SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+#   LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+#   DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+#   THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+#   (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+#   OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+
+ifeq ($(RTE_SDK),)
+$(error "Please define RTE_SDK environment variable")
+endif
+
+# Default target, can be overriden by command line or environment
+RTE_TARGET ?= x86_64-native-linuxapp-gcc
+
+include $(RTE_SDK)/mk/rte.vars.mk
+
+# binary name
+APP = vhost-switch
+
+# all source are stored in SRCS-y
+#SRCS-y := cusedrv.c loopback-userspace.c
+SRCS-y := main.c
+
+CFLAGS += -O2 -I/usr/local/include -D_FILE_OFFSET_BITS=64 -Wno-unused-parameter
+CFLAGS += $(WERROR_FLAGS)
+LDFLAGS += -lfuse
+
+include $(RTE_SDK)/mk/rte.extapp.mk
-- 
1.8.1.4

^ permalink raw reply	[flat|nested] 23+ messages in thread

* Re: [dpdk-dev] [PATCH v5 01/11] lib/librte_vhost: move src files in vhost example to vhost lib directory
  2014-09-26  9:45 ` [dpdk-dev] [PATCH v5 01/11] lib/librte_vhost: move src files in vhost example to vhost lib directory Huawei Xie
@ 2014-09-29 19:41   ` Thomas Monjalon
  2014-09-30  2:07     ` Xie, Huawei
  0 siblings, 1 reply; 23+ messages in thread
From: Thomas Monjalon @ 2014-09-29 19:41 UTC (permalink / raw)
  To: Huawei Xie; +Cc: dev

Hi Huawei,

2014-09-26 17:45, Huawei Xie:
> "git mv examples/vhost lib/librte_vhost"
> This is a purely src file move, without any modification.
> Subsequent patch will transform those src files to a vhost library.
> 
> Signed-off-by: Huawei Xie <huawei.xie@intel.com>
> ---
>  examples/vhost/Makefile                      |   60 -
>  examples/vhost/eventfd_link/Makefile         |   39 -
>  examples/vhost/eventfd_link/eventfd_link.c   |  205 --
>  examples/vhost/eventfd_link/eventfd_link.h   |   79 -
>  examples/vhost/libvirt/qemu-wrap.py          |  367 ---
>  examples/vhost/main.c                        | 3725 --------------------------
>  examples/vhost/main.h                        |   86 -
>  examples/vhost/vhost-net-cdev.c              |  367 ---
>  examples/vhost/vhost-net-cdev.h              |   83 -
>  examples/vhost/virtio-net.c                  | 1165 --------
>  examples/vhost/virtio-net.h                  |  161 --
>  lib/librte_vhost/eventfd_link/Makefile       |   39 +
>  lib/librte_vhost/eventfd_link/eventfd_link.c |  205 ++
>  lib/librte_vhost/eventfd_link/eventfd_link.h |   79 +
>  lib/librte_vhost/libvirt/qemu-wrap.py        |  367 +++
>  lib/librte_vhost/main.c                      | 3725 ++++++++++++++++++++++++++
>  lib/librte_vhost/main.h                      |   86 +
>  lib/librte_vhost/vhost-net-cdev.c            |  367 +++
>  lib/librte_vhost/vhost-net-cdev.h            |   83 +
>  lib/librte_vhost/virtio-net.c                | 1165 ++++++++
>  lib/librte_vhost/virtio-net.h                |  161 ++
>  21 files changed, 6277 insertions(+), 6337 deletions(-)

In patch 2, you're using main.c to create vhost_rxtx.c.
So it would be clearer to rename it in this patch 1.

-- 
Thomas

^ permalink raw reply	[flat|nested] 23+ messages in thread

* Re: [dpdk-dev] [PATCH v5 05/11] lib/librte_vhost: merge Oliver's mbuf change
  2014-09-26  9:45 ` [dpdk-dev] [PATCH v5 05/11] lib/librte_vhost: merge Oliver's mbuf change Huawei Xie
@ 2014-09-29 19:44   ` Thomas Monjalon
       [not found]     ` <C37D651A908B024F974696C65296B57B0F2AF2C0@SHSMSX101.ccr.corp.intel.com>
  0 siblings, 1 reply; 23+ messages in thread
From: Thomas Monjalon @ 2014-09-29 19:44 UTC (permalink / raw)
  To: Huawei Xie; +Cc: dev

> There is no rte_pktmbuf structure in mbuf now. Its fields are merged to
> rte_mbuf structure.
> 
> Signed-off-by: Huawei Xie <huawei.xie@intel.com>

This patch shouldn't appear but should be merged with your previous work.

-- 
Thomas

^ permalink raw reply	[flat|nested] 23+ messages in thread

* Re: [dpdk-dev] [PATCH v5 03/11] lib/librte_vhost: vhost lib transform
  2014-09-26  9:45 ` [dpdk-dev] [PATCH v5 03/11] lib/librte_vhost: vhost lib transform Huawei Xie
@ 2014-09-29 19:51   ` Thomas Monjalon
  0 siblings, 0 replies; 23+ messages in thread
From: Thomas Monjalon @ 2014-09-29 19:51 UTC (permalink / raw)
  To: Huawei Xie; +Cc: dev

2014-09-26 17:45, Huawei Xie:
> This vhost lib consists of five APIs plus several other helper routines
> for feature disable/enable.
> 1) rte_vhost_driver_register initialises vhost driver.
> 2) rte_vhost_driver_callback_register registers the callbacks.
> Callbacks are called from vhost driver when virtio device is ready
> for polling or is de-activated by guest.
> 3) rte_vhost_driver_session_start, a blocking API to start vhost
> message handler session.
> 4) rte_vhost_enqueue_burst and rte_vhost_dequeue_burst for
> enqueue/dequeue to/from virtio ring.

There are probably many things here to split in different patches.
It's not mandatory but would be very nice. Example: a patch to remove
hpa_memory_regions would explain why it is removed.

> Modifications include:
> 1) in vhost_rxtx.c
>    virtio_dev_rx -> rte_vhost_enqueue_burst
>    virtio_dev_tx -> rte_vhost_dequeue_burst
> 2) VMDQ, MAC learning and other switch related logics are removed.
> 3) zero copy feature isn't generic at this stage, and is removed.
> 4) retry logic is removed from vhost rx functions.
> The above three logics will be implemented in example as reference.
> 5) Add several TODO/FIXME:
>    -allow application to disable cmpset reserve in rte_vhost_enqueue_burst
> in case there is no contention.
>    -fix memcpy from mbuf to vring desc when mbuf is chained and the
> desc couldn't hold all the data
>    -fix vhost_set_mem_table possible race condition: two vqs concurrently
> calls set_mem_table which cause saved mem_temp to be overide.
> 6) merge-able feature is removed, which will be merged in subsequent patch.

Please do not remove a feature which is re-added later. It's really difficult
to follow such history.

-- 
Thomas

^ permalink raw reply	[flat|nested] 23+ messages in thread

* Re: [dpdk-dev] [PATCH v5 02/11] lib/librte_vhost: refactor vhost lib for subsequent transform
  2014-09-26  9:45 ` [dpdk-dev] [PATCH v5 02/11] lib/librte_vhost: refactor vhost lib for subsequent transform Huawei Xie
@ 2014-09-29 19:55   ` Thomas Monjalon
  2014-09-29 20:00     ` Thomas Monjalon
  0 siblings, 1 reply; 23+ messages in thread
From: Thomas Monjalon @ 2014-09-29 19:55 UTC (permalink / raw)
  To: Huawei Xie; +Cc: dev

2014-09-26 17:45, Huawei Xie:
> This patch does simple split of the original vhost example source
> files in vhost lib directory.
> vhost rx/tx functions virtio_dev_rx/tx are copied from main.c to
> new file vhost_rxtx.c and license header is added.
> main.c and main.h are removed and will be copied to new vhost
> example in subsequent patch.
> virtio-net.h is renamed to rte_virtio_net.h as API header file.
> 
> Signed-off-by: Huawei Xie <huawei.xie@intel.com>

You are removing functions for mergeable buffer feature.
Please keep it instead of re-adding it later.

-- 
Thomas

^ permalink raw reply	[flat|nested] 23+ messages in thread

* Re: [dpdk-dev] [PATCH v5 02/11] lib/librte_vhost: refactor vhost lib for subsequent transform
  2014-09-29 19:55   ` Thomas Monjalon
@ 2014-09-29 20:00     ` Thomas Monjalon
  0 siblings, 0 replies; 23+ messages in thread
From: Thomas Monjalon @ 2014-09-29 20:00 UTC (permalink / raw)
  To: Huawei Xie; +Cc: dev

2014-09-29 21:55, Thomas Monjalon:
> 2014-09-26 17:45, Huawei Xie:
> > This patch does simple split of the original vhost example source
> > files in vhost lib directory.
> > vhost rx/tx functions virtio_dev_rx/tx are copied from main.c to
> > new file vhost_rxtx.c and license header is added.
> > main.c and main.h are removed and will be copied to new vhost
> > example in subsequent patch.
> > virtio-net.h is renamed to rte_virtio_net.h as API header file.
> > 
> > Signed-off-by: Huawei Xie <huawei.xie@intel.com>
> 
> You are removing functions for mergeable buffer feature.
> Please keep it instead of re-adding it later.

Other comment, you are silently increasing these values to 64:

 #define MAX_PKT_BURST 32               /* Max burst size for RX/TX */
 #define MAX_MRG_PKT_BURST 16   /* Max burst for merge buffers. Set to 1 due to performance issue. */

-- 
Thomas

^ permalink raw reply	[flat|nested] 23+ messages in thread

* Re: [dpdk-dev] [PATCH v5 01/11] lib/librte_vhost: move src files in vhost example to vhost lib directory
  2014-09-29 19:41   ` Thomas Monjalon
@ 2014-09-30  2:07     ` Xie, Huawei
  2014-09-30  4:35       ` Thomas Monjalon
  0 siblings, 1 reply; 23+ messages in thread
From: Xie, Huawei @ 2014-09-30  2:07 UTC (permalink / raw)
  To: Thomas Monjalon; +Cc: dev



> -----Original Message-----
> From: Thomas Monjalon [mailto:thomas.monjalon@6wind.com]
> Sent: Tuesday, September 30, 2014 3:42 AM
> To: Xie, Huawei
> Cc: dev@dpdk.org
> Subject: Re: [dpdk-dev] [PATCH v5 01/11] lib/librte_vhost: move src files in vhost
> example to vhost lib directory
> 
> Hi Huawei,
> 
> 2014-09-26 17:45, Huawei Xie:
> > "git mv examples/vhost lib/librte_vhost"
> > This is a purely src file move, without any modification.
> > Subsequent patch will transform those src files to a vhost library.
> >
> > Signed-off-by: Huawei Xie <huawei.xie@intel.com>
> > ---
> >  examples/vhost/Makefile                      |   60 -
> >  examples/vhost/eventfd_link/Makefile         |   39 -
> >  examples/vhost/eventfd_link/eventfd_link.c   |  205 --
> >  examples/vhost/eventfd_link/eventfd_link.h   |   79 -
> >  examples/vhost/libvirt/qemu-wrap.py          |  367 ---
> >  examples/vhost/main.c                        | 3725 --------------------------
> >  examples/vhost/main.h                        |   86 -
> >  examples/vhost/vhost-net-cdev.c              |  367 ---
> >  examples/vhost/vhost-net-cdev.h              |   83 -
> >  examples/vhost/virtio-net.c                  | 1165 --------
> >  examples/vhost/virtio-net.h                  |  161 --
> >  lib/librte_vhost/eventfd_link/Makefile       |   39 +
> >  lib/librte_vhost/eventfd_link/eventfd_link.c |  205 ++
> >  lib/librte_vhost/eventfd_link/eventfd_link.h |   79 +
> >  lib/librte_vhost/libvirt/qemu-wrap.py        |  367 +++
> >  lib/librte_vhost/main.c                      | 3725 ++++++++++++++++++++++++++
> >  lib/librte_vhost/main.h                      |   86 +
> >  lib/librte_vhost/vhost-net-cdev.c            |  367 +++
> >  lib/librte_vhost/vhost-net-cdev.h            |   83 +
> >  lib/librte_vhost/virtio-net.c                | 1165 ++++++++
> >  lib/librte_vhost/virtio-net.h                |  161 ++
> >  21 files changed, 6277 insertions(+), 6337 deletions(-)
> 
> In patch 2, you're using main.c to create vhost_rxtx.c.
> So it would be clearer to rename it in this patch 1.
> 
Rename it to vhost_rxtx.c?
> --
> Thomas

^ permalink raw reply	[flat|nested] 23+ messages in thread

* Re: [dpdk-dev] [PATCH v5 05/11] lib/librte_vhost: merge Oliver's mbuf change
       [not found]     ` <C37D651A908B024F974696C65296B57B0F2AF2C0@SHSMSX101.ccr.corp.intel.com>
@ 2014-09-30  3:41       ` Ouyang, Changchun
  2014-09-30  4:46       ` Thomas Monjalon
  1 sibling, 0 replies; 23+ messages in thread
From: Ouyang, Changchun @ 2014-09-30  3:41 UTC (permalink / raw)
  To: Xie, Huawei, Thomas Monjalon; +Cc: dev

Hi Huawei,

My response as below.
Thanks
Changchun

> -----Original Message-----
> From: dev [mailto:dev-bounces@dpdk.org] On Behalf Of Xie, Huawei
> Sent: Tuesday, September 30, 2014 10:41 AM
> To: Thomas Monjalon
> Cc: dev@dpdk.org
> Subject: Re: [dpdk-dev] [PATCH v5 05/11] lib/librte_vhost: merge Oliver's
> mbuf change
> 
> > -----Original Message-----
> > From: Thomas Monjalon [mailto:thomas.monjalon@6wind.com]
> > Sent: Tuesday, September 30, 2014 3:44 AM
> > To: Xie, Huawei
> > Cc: dev@dpdk.org
> > Subject: Re: [dpdk-dev] [PATCH v5 05/11] lib/librte_vhost: merge
> > Oliver's mbuf change
> >
> > > There is no rte_pktmbuf structure in mbuf now. Its fields are merged
> > > to rte_mbuf structure.
> > >
> > > Signed-off-by: Huawei Xie <huawei.xie@intel.com>
> >
> > This patch shouldn't appear but should be merged with your previous work.
> >
> > --
> > Thomas
> 
> Hi Thomas:
> I would rework the patch according to your comment.
> I don't get clear about this comment. Do you mean that recreate the patch
> set based on the example that already has this mbuf change?

My understanding is as follows:
Basically every patch file need base on the latest commit, so need merge all changes which have already been applied into mainline,
No only mbuf related change and mergeable feature but also other fix.
"git fetch" and "git pull origin master" may help you, 
If there are conflicts, need resolve them.

And you don't need redo all works from scratch to regenerate the patch files, 
Maybe based on your current commit and do the merge work and resolve some conflicts are the most rework task.
 
> 
> Some of the background you might not know:
> I fully understand your concern here to make it a better patch and I fully
> agree with you total comments.
> This is really a special case. You know it is transform of thousand lines of code
> with modifications.
> Sometimes a simple change could take me more than one day to rework the
> patch, lines of lines manual check.
> I have already spent more than one week of time merely  on the patch
> format itself. :(.
> 
> Could we possibly treat it specially when we have comment whether the
> patch can be split/merged better?

^ permalink raw reply	[flat|nested] 23+ messages in thread

* Re: [dpdk-dev] [PATCH v5 01/11] lib/librte_vhost: move src files in vhost example to vhost lib directory
  2014-09-30  2:07     ` Xie, Huawei
@ 2014-09-30  4:35       ` Thomas Monjalon
  0 siblings, 0 replies; 23+ messages in thread
From: Thomas Monjalon @ 2014-09-30  4:35 UTC (permalink / raw)
  To: Xie, Huawei; +Cc: dev

2014-09-30 02:07, Xie, Huawei:
> > In patch 2, you're using main.c to create vhost_rxtx.c.
> > So it would be clearer to rename it in this patch 1.
> > 
> Rename it to vhost_rxtx.c?

Yes :)
And rename virtio-net.h to rte_virtio_net.h.
Please put all file renaming in the same patch.
Then second patch should be definitive removals.
>From the third patch, you can start reworks.

-- 
Thomas

^ permalink raw reply	[flat|nested] 23+ messages in thread

* Re: [dpdk-dev] [PATCH v5 05/11] lib/librte_vhost: merge Oliver's mbuf change
       [not found]     ` <C37D651A908B024F974696C65296B57B0F2AF2C0@SHSMSX101.ccr.corp.intel.com>
  2014-09-30  3:41       ` Ouyang, Changchun
@ 2014-09-30  4:46       ` Thomas Monjalon
  2014-09-30  6:43         ` Xie, Huawei
  1 sibling, 1 reply; 23+ messages in thread
From: Thomas Monjalon @ 2014-09-30  4:46 UTC (permalink / raw)
  To: Xie, Huawei; +Cc: dev

2014-09-30 02:41, Xie, Huawei:
> I would rework the patch according to your comment.
> I don't get clear about this comment. Do you mean that recreate the patch set
> based on the example that already has this mbuf change?

Yes

> Some of the background you might not know:
> I fully understand your concern here to make it a better patch and I fully agree
> with you total comments. 
> This is really a special case. You know it is transform of thousand lines of code with modifications.
> Sometimes a simple change could take me more than one day to rework the patch, lines of lines manual check. 
> I have already spent more than one week of time merely  on the patch format itself. :(.

I know. I think you are learning (the hard way) how to use git.
As Ouyang said in this thread, you should use "git rebase" 
and especially the --interactive mode to update your changes.
And you should make small commits at first. It's easier to squash
commits than splitting them.

> Could we possibly treat it specially when we have comment whether the patch can be split/merged better? 

I thought it many times because I see it causes you many troubles.
But I still think that vhost is an important feature and we probably
want to be able to understand what are the reasons behond the changes
by looking at the git history. That's why I'd like you to make smaller
refactoring commits with explanations in commit logs.

That's said, we should continue working together on it.
Send me your drafts and I'll help you to split them. The part I cannot do
by myself is about the explanations in commit logs.

Thanks
-- 
Thomas

^ permalink raw reply	[flat|nested] 23+ messages in thread

* Re: [dpdk-dev] [PATCH v5 05/11] lib/librte_vhost: merge Oliver's mbuf change
  2014-09-30  4:46       ` Thomas Monjalon
@ 2014-09-30  6:43         ` Xie, Huawei
  2014-09-30  8:06           ` Thomas Monjalon
  0 siblings, 1 reply; 23+ messages in thread
From: Xie, Huawei @ 2014-09-30  6:43 UTC (permalink / raw)
  To: Thomas Monjalon; +Cc: dev



> -----Original Message-----
> From: Thomas Monjalon [mailto:thomas.monjalon@6wind.com]
> Sent: Tuesday, September 30, 2014 12:46 PM
> To: Xie, Huawei
> Cc: dev@dpdk.org
> Subject: Re: [dpdk-dev] [PATCH v5 05/11] lib/librte_vhost: merge Oliver's mbuf
> change
> 
> 2014-09-30 02:41, Xie, Huawei:
> > I would rework the patch according to your comment.
> > I don't get clear about this comment. Do you mean that recreate the patch set
> > based on the example that already has this mbuf change?
> 
> Yes
> 
> > Some of the background you might not know:
> > I fully understand your concern here to make it a better patch and I fully agree
> > with you total comments.
> > This is really a special case. You know it is transform of thousand lines of code
> with modifications.
> > Sometimes a simple change could take me more than one day to rework the
> patch, lines of lines manual check.
> > I have already spent more than one week of time merely  on the patch format
> itself. :(.
> 

> I know. I think you are learning (the hard way) how to use git.
> As Ouyang said in this thread, you should use "git rebase"
> and especially the --interactive mode to update your changes.
> And you should make small commits at first. It's easier to squash
> commits than splitting them.
> 
> > Could we possibly treat it specially when we have comment whether the patch
> can be split/merged better?
> 
> I thought it many times because I see it causes you many troubles.
> But I still think that vhost is an important feature and we probably
> want to be able to understand what are the reasons behond the changes
> by looking at the git history. That's why I'd like you to make smaller
> refactoring commits with explanations in commit logs.
> 
> That's said, we should continue working together on it.
> Send me your drafts and I'll help you to split them. The part I cannot do
> by myself is about the explanations in commit logs.
>
Based on the principle "small commit", this is the rough idea. Btw, git tool will n't help here. Please have a quick read through. I will start the rework asap.
Patch 1:
	copy examples/vhost/main.c    /lib/librte_vhost/vhost/vhost_rxtx.c
	git mv examples/vhost/eventfd_link  /lib/librte_vhost/
	git mv examples/vhost/libvirt   /lib/librte/vhost/libvirt
	git mv examples/vhost/vhost-net-cdev.c  /lib/librte_vhost/
	git mv examples/vhost/vhost-net-cdev.h /lib/librte_vhost/  
	git mv examples/vhost/virtio-net.* /lib/librte_vhost/
comment:
As in previous patch set, vhost_rxtx.c is partly copied from main.c, here I decide to "copy" rather than "mv" main.c from example to vhost lib. The drawback is gitk couldn't recognize main.c and vhost_rxtx.c have the same index.
The pros is even with mv, gitk couldn't recognize partly copy of vhost_rxtx.c, and later we could patch vhost example based on existing files.
Will emphasize that vhost_rxtx.c is a purely copy without any modification in commit message.
delete examples/vhost/Makefile as vhost example could no longer be compiled from here after until the example patch.

Another option is leave all example files, and copy needed ones to vhost lib directory. The cons is gitk will treat all files in vhost lib as new files. 

patch 2:
	rename virtio-net.c to rte_virtio_net.h
patch 3:
	remove zero copy logic in related files.
patch 4:
	remove switching related logics in related files.
patch 5:
	delete all functions in vhost_rxtx.c except four functions virtio_dev_(merge)_rx/tx and helper functions copy_mbuf_to_rings..
comment here:
	here virtio_dev_(merge)_rx/tx will refer non-existing functions like virtio_tx_route.
I think it is ok, right?
patch 6:
	remove virtio_dev_tx, and rename virtio_dev_merge_tx to
virtio_dev_tx.
	patch virtio_dev_rx, virtio_dev_merge_rx and virtio_dev_tx
	will see if this can be further divided.
patch 7:
	Other minior fixes, like change global vars to static vars
patch 8:
	fixes plenty of serious coding style issues
Patch 9:
	Vhost API patch
Patch 10:
	Added identified TODO or FIXME
patch 11:
	Add vhost lib makefiles.	
Patch 12...:
	Vhost example patch

 
> Thanks
> --
> Thomas

^ permalink raw reply	[flat|nested] 23+ messages in thread

* Re: [dpdk-dev] [PATCH v5 05/11] lib/librte_vhost: merge Oliver's mbuf change
  2014-09-30  6:43         ` Xie, Huawei
@ 2014-09-30  8:06           ` Thomas Monjalon
  0 siblings, 0 replies; 23+ messages in thread
From: Thomas Monjalon @ 2014-09-30  8:06 UTC (permalink / raw)
  To: Xie, Huawei; +Cc: dev

2014-09-30 06:43, Xie, Huawei:
> > 2014-09-30 02:41, Xie, Huawei:
> > > I would rework the patch according to your comment.
> > > I don't get clear about this comment. Do you mean that recreate the patch set
> > > based on the example that already has this mbuf change?
> > 
> > Yes
> > 
> > > Some of the background you might not know:
> > > I fully understand your concern here to make it a better patch and I fully agree
> > > with you total comments.
> > > This is really a special case. You know it is transform of thousand lines of code
> > with modifications.
> > > Sometimes a simple change could take me more than one day to rework the
> > patch, lines of lines manual check.
> > > I have already spent more than one week of time merely  on the patch format
> > itself. :(.
> > 
> 
> > I know. I think you are learning (the hard way) how to use git.
> > As Ouyang said in this thread, you should use "git rebase"
> > and especially the --interactive mode to update your changes.
> > And you should make small commits at first. It's easier to squash
> > commits than splitting them.
> > 
> > > Could we possibly treat it specially when we have comment whether the patch
> > can be split/merged better?
> > 
> > I thought it many times because I see it causes you many troubles.
> > But I still think that vhost is an important feature and we probably
> > want to be able to understand what are the reasons behond the changes
> > by looking at the git history. That's why I'd like you to make smaller
> > refactoring commits with explanations in commit logs.
> > 
> > That's said, we should continue working together on it.
> > Send me your drafts and I'll help you to split them. The part I cannot do
> > by myself is about the explanations in commit logs.
> >
> Based on the principle "small commit", this is the rough idea. Btw, git tool will n't help here. Please have a quick read through. I will start the rework asap.
> Patch 1:
> 	copy examples/vhost/main.c    /lib/librte_vhost/vhost/vhost_rxtx.c
> 	git mv examples/vhost/eventfd_link  /lib/librte_vhost/
> 	git mv examples/vhost/libvirt   /lib/librte/vhost/libvirt
> 	git mv examples/vhost/vhost-net-cdev.c  /lib/librte_vhost/
> 	git mv examples/vhost/vhost-net-cdev.h /lib/librte_vhost/  
> 	git mv examples/vhost/virtio-net.* /lib/librte_vhost/
> comment:
> As in previous patch set, vhost_rxtx.c is partly copied from main.c, here I decide to "copy" rather than "mv" main.c from example to vhost lib. The drawback is gitk couldn't recognize main.c and vhost_rxtx.c have the same index.
> The pros is even with mv, gitk couldn't recognize partly copy of vhost_rxtx.c, and later we could patch vhost example based on existing files.
> Will emphasize that vhost_rxtx.c is a purely copy without any modification in commit message.
> delete examples/vhost/Makefile as vhost example could no longer be compiled from here after until the example patch.
> 
> Another option is leave all example files, and copy needed ones to vhost lib directory. The cons is gitk will treat all files in vhost lib as new files. 

No please move the files to the lib. It's easier to read.
You can drop all the example in 1 patch or make as you did before:
drop old example and rework it in subsequent patches.
The most important part is the library.

> patch 2:
> 	rename virtio-net.c to rte_virtio_net.h

It can be done in patch 1.

> patch 3:
> 	remove zero copy logic in related files.
> patch 4:
> 	remove switching related logics in related files.
> patch 5:
> 	delete all functions in vhost_rxtx.c except four functions virtio_dev_(merge)_rx/tx and helper functions copy_mbuf_to_rings..
> comment here:
> 	here virtio_dev_(merge)_rx/tx will refer non-existing functions like virtio_tx_route.
> I think it is ok, right?
> patch 6:
> 	remove virtio_dev_tx, and rename virtio_dev_merge_tx to
> virtio_dev_tx.
> 	patch virtio_dev_rx, virtio_dev_merge_rx and virtio_dev_tx
> 	will see if this can be further divided.

Yes please try to split and explain these important things.

> patch 7:
> 	Other minior fixes, like change global vars to static vars
> patch 8:
> 	fixes plenty of serious coding style issues
> Patch 9:
> 	Vhost API patch
> Patch 10:
> 	Added identified TODO or FIXME
> patch 11:
> 	Add vhost lib makefiles.	
> Patch 12...:
> 	Vhost example patch

OK for the other ones.
The global idea is to isolate minor changes in order to make important
changes clearly visible in dedicated patches.

-- 
Thomas

^ permalink raw reply	[flat|nested] 23+ messages in thread

end of thread, other threads:[~2014-09-30  8:00 UTC | newest]

Thread overview: 23+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2014-09-26  9:45 [dpdk-dev] [PATCH v5 00/11] user space vhost library and vhost example Huawei Xie
2014-09-26  9:45 ` [dpdk-dev] [PATCH v5 01/11] lib/librte_vhost: move src files in vhost example to vhost lib directory Huawei Xie
2014-09-29 19:41   ` Thomas Monjalon
2014-09-30  2:07     ` Xie, Huawei
2014-09-30  4:35       ` Thomas Monjalon
2014-09-26  9:45 ` [dpdk-dev] [PATCH v5 02/11] lib/librte_vhost: refactor vhost lib for subsequent transform Huawei Xie
2014-09-29 19:55   ` Thomas Monjalon
2014-09-29 20:00     ` Thomas Monjalon
2014-09-26  9:45 ` [dpdk-dev] [PATCH v5 03/11] lib/librte_vhost: vhost lib transform Huawei Xie
2014-09-29 19:51   ` Thomas Monjalon
2014-09-26  9:45 ` [dpdk-dev] [PATCH v5 04/11] lib/librte_vhost: merge vhost merge-able rx. merge vhost tx fix Huawei Xie
2014-09-26  9:45 ` [dpdk-dev] [PATCH v5 05/11] lib/librte_vhost: merge Oliver's mbuf change Huawei Xie
2014-09-29 19:44   ` Thomas Monjalon
     [not found]     ` <C37D651A908B024F974696C65296B57B0F2AF2C0@SHSMSX101.ccr.corp.intel.com>
2014-09-30  3:41       ` Ouyang, Changchun
2014-09-30  4:46       ` Thomas Monjalon
2014-09-30  6:43         ` Xie, Huawei
2014-09-30  8:06           ` Thomas Monjalon
2014-09-26  9:45 ` [dpdk-dev] [PATCH v5 06/11] lib/librte_vhost: fixes serious coding style issues Huawei Xie
2014-09-26  9:45 ` [dpdk-dev] [PATCH v5 07/11] lib/librte_vhost: add vhost support in DPDK makefile Huawei Xie
2014-09-26  9:45 ` [dpdk-dev] [PATCH v5 08/11] examples/vhost: copy old vhost example src file Huawei Xie
2014-09-26  9:45 ` [dpdk-dev] [PATCH v5 09/11] examples/vhost: vhost example based on vhost lib API Huawei Xie
2014-09-26  9:45 ` [dpdk-dev] [PATCH v5 10/11] examples/vhost: merge oliver's mbuf changes to vhost example Huawei Xie
2014-09-26  9:45 ` [dpdk-dev] [PATCH v5 11/11] examples/vhost: add vhost example Makefile Huawei Xie

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