[dpdk-dev] [PATCH 02/13] Refactored IPv4 fragmentation into a proper library

[Anatoly Burakov <anatoly.burakov@intel.com>]

Signed-off-by: Anatoly Burakov <anatoly.burakov@intel.com>
---
 examples/ipv4_frag/main.c                   |  11 ++
 lib/librte_ip_frag/Makefile                 |   9 ++
 lib/librte_ip_frag/rte_ip_frag.h            | 186 +---------------------
 lib/librte_ip_frag/rte_ipv4_fragmentation.c | 239 ++++++++++++++++++++++++++++
 mk/rte.app.mk                               |   4 +
 5 files changed, 267 insertions(+), 182 deletions(-)
 create mode 100644 lib/librte_ip_frag/rte_ipv4_fragmentation.c

diff --git a/examples/ipv4_frag/main.c b/examples/ipv4_frag/main.c
index 3c2c960..05a26b1 100644
--- a/examples/ipv4_frag/main.c
+++ b/examples/ipv4_frag/main.c
@@ -74,6 +74,17 @@
 #include "rte_ip_frag.h"
 #include "main.h"
 
+/*
+ * Default byte size for the IPv4 Maximum Transfer Unit (MTU).
+ * This value includes the size of IPv4 header.
+ */
+#define	IPV4_MTU_DEFAULT	ETHER_MTU
+
+/*
+ * Default payload in bytes for the IPv4 packet.
+ */
+#define	IPV4_DEFAULT_PAYLOAD	(IPV4_MTU_DEFAULT - sizeof(struct ipv4_hdr))
+
 #define RTE_LOGTYPE_L3FWD RTE_LOGTYPE_USER1
 
 #define MBUF_SIZE (2048 + sizeof(struct rte_mbuf) + RTE_PKTMBUF_HEADROOM)
diff --git a/lib/librte_ip_frag/Makefile b/lib/librte_ip_frag/Makefile
index 3054c1f..13a83b1 100644
--- a/lib/librte_ip_frag/Makefile
+++ b/lib/librte_ip_frag/Makefile
@@ -31,6 +31,15 @@
 
 include $(RTE_SDK)/mk/rte.vars.mk
 
+# library name
+LIB = librte_ip_frag.a
+
+CFLAGS += -O3
+CFLAGS += $(WERROR_FLAGS) -I$(SRCDIR)
+
+#source files
+SRCS-$(CONFIG_RTE_LIBRTE_IP_FRAG) += rte_ipv4_fragmentation.c
+
 # install this header file
 SYMLINK-$(CONFIG_RTE_LIBRTE_IP_FRAG)-include += rte_ip_frag.h
 SYMLINK-$(CONFIG_RTE_LIBRTE_IP_FRAG)-include += ipv4_frag_tbl.h
diff --git a/lib/librte_ip_frag/rte_ip_frag.h b/lib/librte_ip_frag/rte_ip_frag.h
index 84fa9c9..0cf3878 100644
--- a/lib/librte_ip_frag/rte_ip_frag.h
+++ b/lib/librte_ip_frag/rte_ip_frag.h
@@ -31,9 +31,8 @@
  *   OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  */
 
-#ifndef __INCLUDE_RTE_IPV4_FRAG_H__
-#define __INCLUDE_RTE_IPV4_FRAG_H__
-#include <rte_ip.h>
+#ifndef _RTE_IP_FRAG_H__
+#define _RTE_IP_FRAG_H__
 
 /**
  * @file
@@ -43,67 +42,6 @@
  *
  */
 
-/*
- * Default byte size for the IPv4 Maximum Transfer Unit (MTU).
- * This value includes the size of IPv4 header.
- */
-#define	IPV4_MTU_DEFAULT	ETHER_MTU
-
-/*
- * Default payload in bytes for the IPv4 packet.
- */
-#define	IPV4_DEFAULT_PAYLOAD	(IPV4_MTU_DEFAULT - sizeof(struct ipv4_hdr))
-
-/*
- * MAX number of fragments per packet allowed.
- */
-#define	IPV4_MAX_FRAGS_PER_PACKET	0x80
-
-
-/* Debug on/off */
-#ifdef RTE_IPV4_FRAG_DEBUG
-
-#define	RTE_IPV4_FRAG_ASSERT(exp)					\
-if (!(exp))	{							\
-	rte_panic("function %s, line%d\tassert \"" #exp "\" failed\n",	\
-		__func__, __LINE__);					\
-}
-
-#else /*RTE_IPV4_FRAG_DEBUG*/
-
-#define RTE_IPV4_FRAG_ASSERT(exp)	do { } while(0)
-
-#endif /*RTE_IPV4_FRAG_DEBUG*/
-
-/* Fragment Offset */
-#define	IPV4_HDR_DF_SHIFT			14
-#define	IPV4_HDR_MF_SHIFT			13
-#define	IPV4_HDR_FO_SHIFT			3
-
-#define	IPV4_HDR_DF_MASK			(1 << IPV4_HDR_DF_SHIFT)
-#define	IPV4_HDR_MF_MASK			(1 << IPV4_HDR_MF_SHIFT)
-
-#define	IPV4_HDR_FO_MASK			((1 << IPV4_HDR_FO_SHIFT) - 1)
-
-static inline void __fill_ipv4hdr_frag(struct ipv4_hdr *dst,
-		const struct ipv4_hdr *src, uint16_t len, uint16_t fofs,
-		uint16_t dofs, uint32_t mf)
-{
-	rte_memcpy(dst, src, sizeof(*dst));
-	fofs = (uint16_t)(fofs + (dofs >> IPV4_HDR_FO_SHIFT));
-	fofs = (uint16_t)(fofs | mf << IPV4_HDR_MF_SHIFT);
-	dst->fragment_offset = rte_cpu_to_be_16(fofs);
-	dst->total_length = rte_cpu_to_be_16(len);
-	dst->hdr_checksum = 0;
-}
-
-static inline void __free_fragments(struct rte_mbuf *mb[], uint32_t num)
-{
-	uint32_t i;
-	for (i = 0; i != num; i++)
-		rte_pktmbuf_free(mb[i]);
-}
-
 /**
  * IPv4 fragmentation.
  *
@@ -125,127 +63,11 @@ static inline void __free_fragments(struct rte_mbuf *mb[], uint32_t num)
  *   in the pkts_out array.
  *   Otherwise - (-1) * <errno>.
  */
-static inline int32_t rte_ipv4_fragmentation(struct rte_mbuf *pkt_in,
+int32_t rte_ipv4_fragmentation(struct rte_mbuf *pkt_in,
 	struct rte_mbuf **pkts_out,
 	uint16_t nb_pkts_out,
 	uint16_t mtu_size,
 	struct rte_mempool *pool_direct,
-	struct rte_mempool *pool_indirect)
-{
-	struct rte_mbuf *in_seg = NULL;
-	struct ipv4_hdr *in_hdr;
-	uint32_t out_pkt_pos, in_seg_data_pos;
-	uint32_t more_in_segs;
-	uint16_t fragment_offset, flag_offset, frag_size;
-
-	frag_size = (uint16_t)(mtu_size - sizeof(struct ipv4_hdr));
-
-	/* Fragment size should be a multiply of 8. */
-	RTE_IPV4_FRAG_ASSERT((frag_size & IPV4_HDR_FO_MASK) == 0);
-
-	/* Fragment size should be a multiply of 8. */
-	RTE_IPV4_FRAG_ASSERT(IPV4_MAX_FRAGS_PER_PACKET * frag_size >=
-	    (uint16_t)(pkt_in->pkt.pkt_len - sizeof (struct ipv4_hdr)));
-
-	in_hdr = (struct ipv4_hdr*) pkt_in->pkt.data;
-	flag_offset = rte_cpu_to_be_16(in_hdr->fragment_offset);
-
-	/* If Don't Fragment flag is set */
-	if (unlikely ((flag_offset & IPV4_HDR_DF_MASK) != 0))
-		return (-ENOTSUP);
-
-	/* Check that pkts_out is big enough to hold all fragments */
-	if (unlikely (frag_size * nb_pkts_out <
-	    (uint16_t)(pkt_in->pkt.pkt_len - sizeof (struct ipv4_hdr))))
-		return (-EINVAL);
-
-	in_seg = pkt_in;
-	in_seg_data_pos = sizeof(struct ipv4_hdr);
-	out_pkt_pos = 0;
-	fragment_offset = 0;
-
-	more_in_segs = 1;
-	while (likely(more_in_segs)) {
-		struct rte_mbuf *out_pkt = NULL, *out_seg_prev = NULL;
-		uint32_t more_out_segs;
-		struct ipv4_hdr *out_hdr;
-
-		/* Allocate direct buffer */
-		out_pkt = rte_pktmbuf_alloc(pool_direct);
-		if (unlikely(out_pkt == NULL)) {
-			__free_fragments(pkts_out, out_pkt_pos);
-			return (-ENOMEM);
-		}
-
-		/* Reserve space for the IP header that will be built later */
-		out_pkt->pkt.data_len = sizeof(struct ipv4_hdr);
-		out_pkt->pkt.pkt_len = sizeof(struct ipv4_hdr);
-
-		out_seg_prev = out_pkt;
-		more_out_segs = 1;
-		while (likely(more_out_segs && more_in_segs)) {
-			struct rte_mbuf *out_seg = NULL;
-			uint32_t len;
-
-			/* Allocate indirect buffer */
-			out_seg = rte_pktmbuf_alloc(pool_indirect);
-			if (unlikely(out_seg == NULL)) {
-				rte_pktmbuf_free(out_pkt);
-				__free_fragments(pkts_out, out_pkt_pos);
-				return (-ENOMEM);
-			}
-			out_seg_prev->pkt.next = out_seg;
-			out_seg_prev = out_seg;
-
-			/* Prepare indirect buffer */
-			rte_pktmbuf_attach(out_seg, in_seg);
-			len = mtu_size - out_pkt->pkt.pkt_len;
-			if (len > (in_seg->pkt.data_len - in_seg_data_pos)) {
-				len = in_seg->pkt.data_len - in_seg_data_pos;
-			}
-			out_seg->pkt.data = (char*) in_seg->pkt.data + (uint16_t)in_seg_data_pos;
-			out_seg->pkt.data_len = (uint16_t)len;
-			out_pkt->pkt.pkt_len = (uint16_t)(len +
-			    out_pkt->pkt.pkt_len);
-			out_pkt->pkt.nb_segs += 1;
-			in_seg_data_pos += len;
-
-			/* Current output packet (i.e. fragment) done ? */
-			if (unlikely(out_pkt->pkt.pkt_len >= mtu_size)) {
-				more_out_segs = 0;
-			}
-
-			/* Current input segment done ? */
-			if (unlikely(in_seg_data_pos == in_seg->pkt.data_len)) {
-				in_seg = in_seg->pkt.next;
-				in_seg_data_pos = 0;
-
-				if (unlikely(in_seg == NULL)) {
-					more_in_segs = 0;
-				}
-			}
-		}
-
-		/* Build the IP header */
-
-		out_hdr = (struct ipv4_hdr*) out_pkt->pkt.data;
-
-		__fill_ipv4hdr_frag(out_hdr, in_hdr,
-		    (uint16_t)out_pkt->pkt.pkt_len,
-		    flag_offset, fragment_offset, more_in_segs);
-
-		fragment_offset = (uint16_t)(fragment_offset +
-		    out_pkt->pkt.pkt_len - sizeof(struct ipv4_hdr));
-
-		out_pkt->ol_flags |= PKT_TX_IP_CKSUM;
-		out_pkt->pkt.vlan_macip.f.l3_len = sizeof(struct ipv4_hdr);
-
-		/* Write the fragment to the output list */
-		pkts_out[out_pkt_pos] = out_pkt;
-		out_pkt_pos ++;
-	}
-
-	return (out_pkt_pos);
-}
+	struct rte_mempool *pool_indirect);
 
 #endif
diff --git a/lib/librte_ip_frag/rte_ipv4_fragmentation.c b/lib/librte_ip_frag/rte_ipv4_fragmentation.c
new file mode 100644
index 0000000..2d33a7b
--- /dev/null
+++ b/lib/librte_ip_frag/rte_ipv4_fragmentation.c
@@ -0,0 +1,239 @@
+/*-
+ *   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 <stddef.h>
+#include <stdint.h>
+#include <errno.h>
+
+#include <rte_byteorder.h>
+#include <rte_memcpy.h>
+#include <rte_mempool.h>
+#include <rte_debug.h>
+#include <rte_mbuf.h>
+#include <rte_ip.h>
+
+#include "rte_ip_frag.h"
+
+/*
+ * MAX number of fragments per packet allowed.
+ */
+#define	IPV4_MAX_FRAGS_PER_PACKET	0x80
+
+/* Debug on/off */
+#ifdef RTE_IPV4_FRAG_DEBUG
+
+#define	RTE_IPV4_FRAG_ASSERT(exp)					\
+if (!(exp))	{							\
+	rte_panic("function %s, line%d\tassert \"" #exp "\" failed\n",	\
+		__func__, __LINE__);					\
+}
+
+#else /*RTE_IPV4_FRAG_DEBUG*/
+
+#define RTE_IPV4_FRAG_ASSERT(exp)	do { } while(0)
+
+#endif /*RTE_IPV4_FRAG_DEBUG*/
+
+/* Fragment Offset */
+#define	IPV4_HDR_DF_SHIFT			14
+#define	IPV4_HDR_MF_SHIFT			13
+#define	IPV4_HDR_FO_SHIFT			3
+
+#define	IPV4_HDR_DF_MASK			(1 << IPV4_HDR_DF_SHIFT)
+#define	IPV4_HDR_MF_MASK			(1 << IPV4_HDR_MF_SHIFT)
+
+#define	IPV4_HDR_FO_MASK			((1 << IPV4_HDR_FO_SHIFT) - 1)
+
+static inline void __fill_ipv4hdr_frag(struct ipv4_hdr *dst,
+		const struct ipv4_hdr *src, uint16_t len, uint16_t fofs,
+		uint16_t dofs, uint32_t mf)
+{
+	rte_memcpy(dst, src, sizeof(*dst));
+	fofs = (uint16_t)(fofs + (dofs >> IPV4_HDR_FO_SHIFT));
+	fofs = (uint16_t)(fofs | mf << IPV4_HDR_MF_SHIFT);
+	dst->fragment_offset = rte_cpu_to_be_16(fofs);
+	dst->total_length = rte_cpu_to_be_16(len);
+	dst->hdr_checksum = 0;
+}
+
+static inline void __free_fragments(struct rte_mbuf *mb[], uint32_t num)
+{
+	uint32_t i;
+	for (i = 0; i != num; i++)
+		rte_pktmbuf_free(mb[i]);
+}
+
+/**
+ * IPv4 fragmentation.
+ *
+ * This function implements the fragmentation of IPv4 packets.
+ *
+ * @param pkt_in
+ *   The input packet.
+ * @param pkts_out
+ *   Array storing the output fragments.
+ * @param mtu_size
+ *   Size in bytes of the Maximum Transfer Unit (MTU) for the outgoing IPv4
+ *   datagrams. This value includes the size of the IPv4 header.
+ * @param pool_direct
+ *   MBUF pool used for allocating direct buffers for the output fragments.
+ * @param pool_indirect
+ *   MBUF pool used for allocating indirect buffers for the output fragments.
+ * @return
+ *   Upon successful completion - number of output fragments placed
+ *   in the pkts_out array.
+ *   Otherwise - (-1) * <errno>.
+ */
+int32_t
+rte_ipv4_fragmentation(struct rte_mbuf *pkt_in,
+	struct rte_mbuf **pkts_out,
+	uint16_t nb_pkts_out,
+	uint16_t mtu_size,
+	struct rte_mempool *pool_direct,
+	struct rte_mempool *pool_indirect)
+{
+	struct rte_mbuf *in_seg = NULL;
+	struct ipv4_hdr *in_hdr;
+	uint32_t out_pkt_pos, in_seg_data_pos;
+	uint32_t more_in_segs;
+	uint16_t fragment_offset, flag_offset, frag_size;
+
+	frag_size = (uint16_t)(mtu_size - sizeof(struct ipv4_hdr));
+
+	/* Fragment size should be a multiply of 8. */
+	RTE_IPV4_FRAG_ASSERT((frag_size & IPV4_HDR_FO_MASK) == 0);
+
+	/* Fragment size should be a multiply of 8. */
+	RTE_IPV4_FRAG_ASSERT(IPV4_MAX_FRAGS_PER_PACKET * frag_size >=
+	    (uint16_t)(pkt_in->pkt.pkt_len - sizeof (struct ipv4_hdr)));
+
+	in_hdr = (struct ipv4_hdr*) pkt_in->pkt.data;
+	flag_offset = rte_cpu_to_be_16(in_hdr->fragment_offset);
+
+	/* If Don't Fragment flag is set */
+	if (unlikely ((flag_offset & IPV4_HDR_DF_MASK) != 0))
+		return (-ENOTSUP);
+
+	/* Check that pkts_out is big enough to hold all fragments */
+	if (unlikely (frag_size * nb_pkts_out <
+	    (uint16_t)(pkt_in->pkt.pkt_len - sizeof (struct ipv4_hdr))))
+		return (-EINVAL);
+
+	in_seg = pkt_in;
+	in_seg_data_pos = sizeof(struct ipv4_hdr);
+	out_pkt_pos = 0;
+	fragment_offset = 0;
+
+	more_in_segs = 1;
+	while (likely(more_in_segs)) {
+		struct rte_mbuf *out_pkt = NULL, *out_seg_prev = NULL;
+		uint32_t more_out_segs;
+		struct ipv4_hdr *out_hdr;
+
+		/* Allocate direct buffer */
+		out_pkt = rte_pktmbuf_alloc(pool_direct);
+		if (unlikely(out_pkt == NULL)) {
+			__free_fragments(pkts_out, out_pkt_pos);
+			return (-ENOMEM);
+		}
+
+		/* Reserve space for the IP header that will be built later */
+		out_pkt->pkt.data_len = sizeof(struct ipv4_hdr);
+		out_pkt->pkt.pkt_len = sizeof(struct ipv4_hdr);
+
+		out_seg_prev = out_pkt;
+		more_out_segs = 1;
+		while (likely(more_out_segs && more_in_segs)) {
+			struct rte_mbuf *out_seg = NULL;
+			uint32_t len;
+
+			/* Allocate indirect buffer */
+			out_seg = rte_pktmbuf_alloc(pool_indirect);
+			if (unlikely(out_seg == NULL)) {
+				rte_pktmbuf_free(out_pkt);
+				__free_fragments(pkts_out, out_pkt_pos);
+				return (-ENOMEM);
+			}
+			out_seg_prev->pkt.next = out_seg;
+			out_seg_prev = out_seg;
+
+			/* Prepare indirect buffer */
+			rte_pktmbuf_attach(out_seg, in_seg);
+			len = mtu_size - out_pkt->pkt.pkt_len;
+			if (len > (in_seg->pkt.data_len - in_seg_data_pos)) {
+				len = in_seg->pkt.data_len - in_seg_data_pos;
+			}
+			out_seg->pkt.data = (char*) in_seg->pkt.data + (uint16_t)in_seg_data_pos;
+			out_seg->pkt.data_len = (uint16_t)len;
+			out_pkt->pkt.pkt_len = (uint16_t)(len +
+			    out_pkt->pkt.pkt_len);
+			out_pkt->pkt.nb_segs += 1;
+			in_seg_data_pos += len;
+
+			/* Current output packet (i.e. fragment) done ? */
+			if (unlikely(out_pkt->pkt.pkt_len >= mtu_size)) {
+				more_out_segs = 0;
+			}
+
+			/* Current input segment done ? */
+			if (unlikely(in_seg_data_pos == in_seg->pkt.data_len)) {
+				in_seg = in_seg->pkt.next;
+				in_seg_data_pos = 0;
+
+				if (unlikely(in_seg == NULL)) {
+					more_in_segs = 0;
+				}
+			}
+		}
+
+		/* Build the IP header */
+
+		out_hdr = (struct ipv4_hdr*) out_pkt->pkt.data;
+
+		__fill_ipv4hdr_frag(out_hdr, in_hdr,
+		    (uint16_t)out_pkt->pkt.pkt_len,
+		    flag_offset, fragment_offset, more_in_segs);
+
+		fragment_offset = (uint16_t)(fragment_offset +
+		    out_pkt->pkt.pkt_len - sizeof(struct ipv4_hdr));
+
+		out_pkt->ol_flags |= PKT_TX_IP_CKSUM;
+		out_pkt->pkt.vlan_macip.f.l3_len = sizeof(struct ipv4_hdr);
+
+		/* Write the fragment to the output list */
+		pkts_out[out_pkt_pos] = out_pkt;
+		out_pkt_pos ++;
+	}
+
+	return (out_pkt_pos);
+}
diff --git a/mk/rte.app.mk b/mk/rte.app.mk
index a836577..058e362 100644
--- a/mk/rte.app.mk
+++ b/mk/rte.app.mk
@@ -113,6 +113,10 @@ ifeq ($(CONFIG_RTE_LIBRTE_MBUF),y)
 LDLIBS += -lrte_mbuf
 endif
 
+ifeq ($(CONFIG_RTE_LIBRTE_IP_FRAG),y)
+LDLIBS += -lrte_ip_frag
+endif
+
 ifeq ($(CONFIG_RTE_LIBRTE_ETHER),y)
 LDLIBS += -lethdev
 endif
-- 
1.8.1.4