Re: [dpdk-dev] [ [PATCH v2] 11/13] virtio_ioport: armv7/v8: mmap virtio iopci bar region

[Santosh Shukla <sshukla@mvista.com>]

On Wed, Dec 16, 2015 at 6:59 PM, Yuanhan Liu
<yuanhan.liu@linux.intel.com> wrote:
> On Mon, Dec 14, 2015 at 06:30:30PM +0530, Santosh Shukla wrote:
>> Introducing module to mmap iopci bar region. Applicable for linuxapp for non-x86
>> archs, Tested for arm64/ThunderX platform for linux. For that adding two global
>> api.
>> - virtio_ioport_init
>> - virtio_ioport_unmap
>>
>> Signed-off-by: Santosh Shukla <sshukla@mvista.com>
>> Signed-off-by: Rizwan Ansari <ransari@mvista.com>
>> Signed-off-by: Rakesh Krishnamurthy <rakeshk@mvista.com>
>> ---
>>  drivers/net/virtio/Makefile        |    1 +
>>  drivers/net/virtio/virtio_ioport.c |  163 ++++++++++++++++++++++++++++++++++++
>>  drivers/net/virtio/virtio_ioport.h |   42 ++++++++++
>>  3 files changed, 206 insertions(+)
>>  create mode 100644 drivers/net/virtio/virtio_ioport.c
>>  create mode 100644 drivers/net/virtio/virtio_ioport.h
>>
>> diff --git a/drivers/net/virtio/Makefile b/drivers/net/virtio/Makefile
>> index 25a842d..5cba6d3 100644
>> --- a/drivers/net/virtio/Makefile
>> +++ b/drivers/net/virtio/Makefile
>> @@ -50,6 +50,7 @@ SRCS-$(CONFIG_RTE_LIBRTE_VIRTIO_PMD) += virtqueue.c
>>  SRCS-$(CONFIG_RTE_LIBRTE_VIRTIO_PMD) += virtio_pci.c
>>  SRCS-$(CONFIG_RTE_LIBRTE_VIRTIO_PMD) += virtio_rxtx.c
>>  SRCS-$(CONFIG_RTE_LIBRTE_VIRTIO_PMD) += virtio_ethdev.c
>> +SRCS-$(CONFIG_RTE_LIBRTE_VIRTIO_PMD) += virtio_ioport.c
>>  SRCS-$(CONFIG_RTE_VIRTIO_INC_VECTOR) += virtio_rxtx_simple.c
>>
>>  # this lib depends upon:
>> diff --git a/drivers/net/virtio/virtio_ioport.c b/drivers/net/virtio/virtio_ioport.c
>> new file mode 100644
>> index 0000000..ffeb8e9
>> --- /dev/null
>> +++ b/drivers/net/virtio/virtio_ioport.c
>> @@ -0,0 +1,163 @@
>> +/*
>> + *   BSD LICENSE
>> + *
>> + *   Copyright(c) 2015 Cavium Networks. 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 "virtio_ioport.h"
>> +
>> +#if defined(RTE_EXEC_ENV_LINUXAPP) && (defined(RTE_ARCH_ARM) || \
>> +             defined(RTE_ARCH_ARM64))
>> +
>> +#include <sys/types.h>
>> +#include <sys/stat.h>
>> +#include <fcntl.h>
>> +#include <errno.h>
>> +#include <unistd.h>
>> +#include <sys/mman.h>
>> +#include <exec-env/rte_virt_ioport.h>
>> +
>> +#include "virtio_logs.h"
>> +
>> +/* start address of first pci_iobar slot (user-space virtual-addres) */
>> +void *ioport_map;
>
> You still forgot "static"?
>

I misunderstood last comment, sorry we'll do.

>> +/**
>> + * ioport map count,
>> + * Use-case: virtio-net-pci.
>
> How about removing above two lines; it's quite meaningless here, but
> instead a bit redundant.
>

ok.

>> + * Keeps track of number of virtio-net-pci device mapped/unmapped. Max device
>> + * support by linux kernel is 31, so ioport_map_cnt can not be greater than 31.
>> + */
>> +static int ioport_map_cnt;
>> +
>> +static int
>> +virtio_map_ioport(void **resource_addr)
>> +{
>> +     int fd;
>> +     int ret = 0;
>> +
>> +     /* avoid -Werror=unused-parameter, keep compiler happy */
>> +     (void)resource_addr;
>
> Using __rte_unused is more elegant.
>

ok.

>> +     fd = open(VIRT_IOPORT_DEV, O_RDWR);
>> +     if (fd < 0) {
>> +             PMD_INIT_LOG(ERR, "device file %s open error: %d\n",
>> +                          DEV_NAME, fd);
>> +             ret = -1;
>> +             goto out;
>> +     }
>> +
>> +     ioport_map = mmap(NULL, PCI_VIRT_IOPORT_SIZE,
>> +                     PROT_EXEC | PROT_WRITE | PROT_READ, MAP_SHARED, fd, 0);
>> +
>> +     if (ioport_map == MAP_FAILED) {
>> +             PMD_INIT_LOG(ERR, "mmap: failed to map bar Address=%p\n",
>> +                             *resource_addr);
>> +             ret = -ENOMEM;
>> +             goto out1;
>> +     }
>> +
>> +     PMD_INIT_LOG(INFO, "First pci_iobar mapped at %p\n", ioport_map);
>> +
>> +out1:
>> +     close(fd);
>> +out:
>> +     return ret;
>> +}
>> +
>> +static int
>> +virtio_set_ioport_addr(void **resource_addr, unsigned long offset)
>> +{
>> +     int ret = 0;
>> +
>> +     if (ioport_map_cnt >= PCI_VIRT_IOPORT_MAX) {
>> +             ret = -1;
>> +             PMD_INIT_LOG(ERR,
>> +                          "ioport_map_cnt(%d) greater than"
>> +                          "PCI_VIRT_IOPORT_MAX(%d)\n",
>> +                          ioport_map_cnt, PCI_VIRT_IOPORT_MAX);
>> +             return ret;
>> +     }
>> +     *resource_addr = (void *)((char *)ioport_map + (ioport_map_cnt)*offset);
>
> Redundant (), and the void * cast seems to be unnecessary.
>

(void *) is unnecessary, but couldn't get the redundant() part?

>> +     ioport_map_cnt++;
>> +
>> +     PMD_INIT_LOG(DEBUG, "pci.resource_addr %p ioport_map_cnt %d\n",
>> +                     *resource_addr, ioport_map_cnt);
>> +     return ret;
>> +}
>> +
>> +int virtio_ioport_init(struct rte_pci_resource *mem_resource)
>> +{
>> +     int ret = 0;
>> +
>> +     /**
>> +      * Map the all IOBAR entry from /proc/ioport to 4k page_size only once.
>> +      * Later virtio_set_ioport_addr() func will update correct bar_addr for
>> +      * each ioport (i.e..pci_dev->mem_resource[0].addr)
>> +      */
>> +     if (!ioport_map) {
>> +             ret = virtio_map_ioport(&mem_resource->addr);
>> +             if (ret < 0)
>> +                     return ret;
>> +             PMD_INIT_LOG(INFO, "ioport_map %p\n", ioport_map);
>> +     }
>> +
>> +     ret = virtio_set_ioport_addr(&mem_resource->addr, mem_resource->len);
>> +     if (ret < 0)
>> +             return ret;
>> +
>> +     PMD_INIT_LOG(INFO, "resource_addr %p resource_len :%ld\n",
>> +                     mem_resource->addr, (unsigned long)mem_resource->len);
>> +     return ret;
>> +}
>> +
>> +void virtio_ioport_unmap(void)
>> +{
>> +     /* unmap ioport memory */
>
> Redundant comment.
>

ok.
>> +     ioport_map_cnt--;
>> +     if (!ioport_map_cnt)
>> +             munmap(ioport_map, PCI_VIRT_IOPORT_SIZE);
>> +
>> +     PMD_INIT_LOG(DEBUG, "unmapping ioport_mem %d\n", ioport_map_cnt);
>> +}
>> +
>> +#else /* !LINUXAPP && !ARM/64 */
>> +
>> +int virtio_ioport_init(struct rte_pci_resource *mem_resource)
>> +{
>> +     (void)mem_resource;
>
> ditto.
>
Is it redundant comment or your suggesting to use : r / (void) / __rte_unused?

>> +     return 0;
>> +}
>> +
>> +void virtio_ioport_unmap(void)
>> +{
>> +     return;
>> +}
>> +
>> +#endif /* LINUXAPP, ARM/64 */
>> diff --git a/drivers/net/virtio/virtio_ioport.h b/drivers/net/virtio/virtio_ioport.h
>> new file mode 100644
>> index 0000000..bf79551
>> --- /dev/null
>> +++ b/drivers/net/virtio/virtio_ioport.h
>> @@ -0,0 +1,42 @@
>> +/*
>> + *   BSD LICENSE
>> + *
>> + *   Copyright(c) 2015 Cavium Networks. 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_IOPORT_H_
>> +#define _VIRTIO_IOPORT_H_
>> +
>> +#include <rte_pci.h>
>> +
>> +int virtio_ioport_init(struct rte_pci_resource *mem_resource);
>> +void virtio_ioport_unmap(void);
>> +
>> +#endif /* _VIRTIO_IOPORT_H_ */
>> --
>> 1.7.9.5