Imported Upstream version 16.04
[deb_dpdk.git] / app / test-pmd / csumonly.c
diff --git a/app/test-pmd/csumonly.c b/app/test-pmd/csumonly.c
new file mode 100644 (file)
index 0000000..7e4f662
--- /dev/null
@@ -0,0 +1,873 @@
+/*-
+ *   BSD LICENSE
+ *
+ *   Copyright(c) 2010-2014 Intel Corporation. All rights reserved.
+ *   Copyright 2014 6WIND S.A.
+ *   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 <stdarg.h>
+#include <stdio.h>
+#include <errno.h>
+#include <stdint.h>
+#include <unistd.h>
+#include <inttypes.h>
+
+#include <sys/queue.h>
+#include <sys/stat.h>
+
+#include <rte_common.h>
+#include <rte_byteorder.h>
+#include <rte_log.h>
+#include <rte_debug.h>
+#include <rte_cycles.h>
+#include <rte_memory.h>
+#include <rte_memcpy.h>
+#include <rte_memzone.h>
+#include <rte_launch.h>
+#include <rte_eal.h>
+#include <rte_per_lcore.h>
+#include <rte_lcore.h>
+#include <rte_atomic.h>
+#include <rte_branch_prediction.h>
+#include <rte_ring.h>
+#include <rte_memory.h>
+#include <rte_mempool.h>
+#include <rte_mbuf.h>
+#include <rte_memcpy.h>
+#include <rte_interrupts.h>
+#include <rte_pci.h>
+#include <rte_ether.h>
+#include <rte_ethdev.h>
+#include <rte_ip.h>
+#include <rte_tcp.h>
+#include <rte_udp.h>
+#include <rte_sctp.h>
+#include <rte_prefetch.h>
+#include <rte_string_fns.h>
+#include "testpmd.h"
+
+#define IP_DEFTTL  64   /* from RFC 1340. */
+#define IP_VERSION 0x40
+#define IP_HDRLEN  0x05 /* default IP header length == five 32-bits words. */
+#define IP_VHL_DEF (IP_VERSION | IP_HDRLEN)
+
+#define GRE_KEY_PRESENT 0x2000
+#define GRE_KEY_LEN     4
+#define GRE_SUPPORTED_FIELDS GRE_KEY_PRESENT
+
+/* We cannot use rte_cpu_to_be_16() on a constant in a switch/case */
+#if RTE_BYTE_ORDER == RTE_LITTLE_ENDIAN
+#define _htons(x) ((uint16_t)((((x) & 0x00ffU) << 8) | (((x) & 0xff00U) >> 8)))
+#else
+#define _htons(x) (x)
+#endif
+
+/* structure that caches offload info for the current packet */
+struct testpmd_offload_info {
+       uint16_t ethertype;
+       uint16_t l2_len;
+       uint16_t l3_len;
+       uint16_t l4_len;
+       uint8_t l4_proto;
+       uint8_t is_tunnel;
+       uint16_t outer_ethertype;
+       uint16_t outer_l2_len;
+       uint16_t outer_l3_len;
+       uint8_t outer_l4_proto;
+       uint16_t tso_segsz;
+};
+
+/* simplified GRE header */
+struct simple_gre_hdr {
+       uint16_t flags;
+       uint16_t proto;
+} __attribute__((__packed__));
+
+static uint16_t
+get_psd_sum(void *l3_hdr, uint16_t ethertype, uint64_t ol_flags)
+{
+       if (ethertype == _htons(ETHER_TYPE_IPv4))
+               return rte_ipv4_phdr_cksum(l3_hdr, ol_flags);
+       else /* assume ethertype == ETHER_TYPE_IPv6 */
+               return rte_ipv6_phdr_cksum(l3_hdr, ol_flags);
+}
+
+static uint16_t
+get_udptcp_checksum(void *l3_hdr, void *l4_hdr, uint16_t ethertype)
+{
+       if (ethertype == _htons(ETHER_TYPE_IPv4))
+               return rte_ipv4_udptcp_cksum(l3_hdr, l4_hdr);
+       else /* assume ethertype == ETHER_TYPE_IPv6 */
+               return rte_ipv6_udptcp_cksum(l3_hdr, l4_hdr);
+}
+
+/* Parse an IPv4 header to fill l3_len, l4_len, and l4_proto */
+static void
+parse_ipv4(struct ipv4_hdr *ipv4_hdr, struct testpmd_offload_info *info)
+{
+       struct tcp_hdr *tcp_hdr;
+
+       info->l3_len = (ipv4_hdr->version_ihl & 0x0f) * 4;
+       info->l4_proto = ipv4_hdr->next_proto_id;
+
+       /* only fill l4_len for TCP, it's useful for TSO */
+       if (info->l4_proto == IPPROTO_TCP) {
+               tcp_hdr = (struct tcp_hdr *)((char *)ipv4_hdr + info->l3_len);
+               info->l4_len = (tcp_hdr->data_off & 0xf0) >> 2;
+       } else
+               info->l4_len = 0;
+}
+
+/* Parse an IPv6 header to fill l3_len, l4_len, and l4_proto */
+static void
+parse_ipv6(struct ipv6_hdr *ipv6_hdr, struct testpmd_offload_info *info)
+{
+       struct tcp_hdr *tcp_hdr;
+
+       info->l3_len = sizeof(struct ipv6_hdr);
+       info->l4_proto = ipv6_hdr->proto;
+
+       /* only fill l4_len for TCP, it's useful for TSO */
+       if (info->l4_proto == IPPROTO_TCP) {
+               tcp_hdr = (struct tcp_hdr *)((char *)ipv6_hdr + info->l3_len);
+               info->l4_len = (tcp_hdr->data_off & 0xf0) >> 2;
+       } else
+               info->l4_len = 0;
+}
+
+/*
+ * Parse an ethernet header to fill the ethertype, l2_len, l3_len and
+ * ipproto. This function is able to recognize IPv4/IPv6 with one optional vlan
+ * header. The l4_len argument is only set in case of TCP (useful for TSO).
+ */
+static void
+parse_ethernet(struct ether_hdr *eth_hdr, struct testpmd_offload_info *info)
+{
+       struct ipv4_hdr *ipv4_hdr;
+       struct ipv6_hdr *ipv6_hdr;
+
+       info->l2_len = sizeof(struct ether_hdr);
+       info->ethertype = eth_hdr->ether_type;
+
+       if (info->ethertype == _htons(ETHER_TYPE_VLAN)) {
+               struct vlan_hdr *vlan_hdr = (struct vlan_hdr *)(eth_hdr + 1);
+
+               info->l2_len  += sizeof(struct vlan_hdr);
+               info->ethertype = vlan_hdr->eth_proto;
+       }
+
+       switch (info->ethertype) {
+       case _htons(ETHER_TYPE_IPv4):
+               ipv4_hdr = (struct ipv4_hdr *) ((char *)eth_hdr + info->l2_len);
+               parse_ipv4(ipv4_hdr, info);
+               break;
+       case _htons(ETHER_TYPE_IPv6):
+               ipv6_hdr = (struct ipv6_hdr *) ((char *)eth_hdr + info->l2_len);
+               parse_ipv6(ipv6_hdr, info);
+               break;
+       default:
+               info->l4_len = 0;
+               info->l3_len = 0;
+               info->l4_proto = 0;
+               break;
+       }
+}
+
+/* Parse a vxlan header */
+static void
+parse_vxlan(struct udp_hdr *udp_hdr,
+           struct testpmd_offload_info *info,
+           uint32_t pkt_type)
+{
+       struct ether_hdr *eth_hdr;
+
+       /* check udp destination port, 4789 is the default vxlan port
+        * (rfc7348) or that the rx offload flag is set (i40e only
+        * currently) */
+       if (udp_hdr->dst_port != _htons(4789) &&
+               RTE_ETH_IS_TUNNEL_PKT(pkt_type) == 0)
+               return;
+
+       info->is_tunnel = 1;
+       info->outer_ethertype = info->ethertype;
+       info->outer_l2_len = info->l2_len;
+       info->outer_l3_len = info->l3_len;
+       info->outer_l4_proto = info->l4_proto;
+
+       eth_hdr = (struct ether_hdr *)((char *)udp_hdr +
+               sizeof(struct udp_hdr) +
+               sizeof(struct vxlan_hdr));
+
+       parse_ethernet(eth_hdr, info);
+       info->l2_len += ETHER_VXLAN_HLEN; /* add udp + vxlan */
+}
+
+/* Parse a gre header */
+static void
+parse_gre(struct simple_gre_hdr *gre_hdr, struct testpmd_offload_info *info)
+{
+       struct ether_hdr *eth_hdr;
+       struct ipv4_hdr *ipv4_hdr;
+       struct ipv6_hdr *ipv6_hdr;
+       uint8_t gre_len = 0;
+
+       /* check which fields are supported */
+       if ((gre_hdr->flags & _htons(~GRE_SUPPORTED_FIELDS)) != 0)
+               return;
+
+       gre_len += sizeof(struct simple_gre_hdr);
+
+       if (gre_hdr->flags & _htons(GRE_KEY_PRESENT))
+               gre_len += GRE_KEY_LEN;
+
+       if (gre_hdr->proto == _htons(ETHER_TYPE_IPv4)) {
+               info->is_tunnel = 1;
+               info->outer_ethertype = info->ethertype;
+               info->outer_l2_len = info->l2_len;
+               info->outer_l3_len = info->l3_len;
+               info->outer_l4_proto = info->l4_proto;
+
+               ipv4_hdr = (struct ipv4_hdr *)((char *)gre_hdr + gre_len);
+
+               parse_ipv4(ipv4_hdr, info);
+               info->ethertype = _htons(ETHER_TYPE_IPv4);
+               info->l2_len = 0;
+
+       } else if (gre_hdr->proto == _htons(ETHER_TYPE_IPv6)) {
+               info->is_tunnel = 1;
+               info->outer_ethertype = info->ethertype;
+               info->outer_l2_len = info->l2_len;
+               info->outer_l3_len = info->l3_len;
+               info->outer_l4_proto = info->l4_proto;
+
+               ipv6_hdr = (struct ipv6_hdr *)((char *)gre_hdr + gre_len);
+
+               info->ethertype = _htons(ETHER_TYPE_IPv6);
+               parse_ipv6(ipv6_hdr, info);
+               info->l2_len = 0;
+
+       } else if (gre_hdr->proto == _htons(ETHER_TYPE_TEB)) {
+               info->is_tunnel = 1;
+               info->outer_ethertype = info->ethertype;
+               info->outer_l2_len = info->l2_len;
+               info->outer_l3_len = info->l3_len;
+               info->outer_l4_proto = info->l4_proto;
+
+               eth_hdr = (struct ether_hdr *)((char *)gre_hdr + gre_len);
+
+               parse_ethernet(eth_hdr, info);
+       } else
+               return;
+
+       info->l2_len += gre_len;
+}
+
+
+/* Parse an encapsulated ip or ipv6 header */
+static void
+parse_encap_ip(void *encap_ip, struct testpmd_offload_info *info)
+{
+       struct ipv4_hdr *ipv4_hdr = encap_ip;
+       struct ipv6_hdr *ipv6_hdr = encap_ip;
+       uint8_t ip_version;
+
+       ip_version = (ipv4_hdr->version_ihl & 0xf0) >> 4;
+
+       if (ip_version != 4 && ip_version != 6)
+               return;
+
+       info->is_tunnel = 1;
+       info->outer_ethertype = info->ethertype;
+       info->outer_l2_len = info->l2_len;
+       info->outer_l3_len = info->l3_len;
+
+       if (ip_version == 4) {
+               parse_ipv4(ipv4_hdr, info);
+               info->ethertype = _htons(ETHER_TYPE_IPv4);
+       } else {
+               parse_ipv6(ipv6_hdr, info);
+               info->ethertype = _htons(ETHER_TYPE_IPv6);
+       }
+       info->l2_len = 0;
+}
+
+/* modify the IPv4 or IPv4 source address of a packet */
+static void
+change_ip_addresses(void *l3_hdr, uint16_t ethertype)
+{
+       struct ipv4_hdr *ipv4_hdr = l3_hdr;
+       struct ipv6_hdr *ipv6_hdr = l3_hdr;
+
+       if (ethertype == _htons(ETHER_TYPE_IPv4)) {
+               ipv4_hdr->src_addr =
+                       rte_cpu_to_be_32(rte_be_to_cpu_32(ipv4_hdr->src_addr) + 1);
+       } else if (ethertype == _htons(ETHER_TYPE_IPv6)) {
+               ipv6_hdr->src_addr[15] = ipv6_hdr->src_addr[15] + 1;
+       }
+}
+
+/* if possible, calculate the checksum of a packet in hw or sw,
+ * depending on the testpmd command line configuration */
+static uint64_t
+process_inner_cksums(void *l3_hdr, const struct testpmd_offload_info *info,
+       uint16_t testpmd_ol_flags)
+{
+       struct ipv4_hdr *ipv4_hdr = l3_hdr;
+       struct udp_hdr *udp_hdr;
+       struct tcp_hdr *tcp_hdr;
+       struct sctp_hdr *sctp_hdr;
+       uint64_t ol_flags = 0;
+
+       if (info->ethertype == _htons(ETHER_TYPE_IPv4)) {
+               ipv4_hdr = l3_hdr;
+               ipv4_hdr->hdr_checksum = 0;
+
+               ol_flags |= PKT_TX_IPV4;
+               if (info->tso_segsz != 0 && info->l4_proto == IPPROTO_TCP) {
+                       ol_flags |= PKT_TX_IP_CKSUM;
+               } else {
+                       if (testpmd_ol_flags & TESTPMD_TX_OFFLOAD_IP_CKSUM)
+                               ol_flags |= PKT_TX_IP_CKSUM;
+                       else
+                               ipv4_hdr->hdr_checksum =
+                                       rte_ipv4_cksum(ipv4_hdr);
+               }
+       } else if (info->ethertype == _htons(ETHER_TYPE_IPv6))
+               ol_flags |= PKT_TX_IPV6;
+       else
+               return 0; /* packet type not supported, nothing to do */
+
+       if (info->l4_proto == IPPROTO_UDP) {
+               udp_hdr = (struct udp_hdr *)((char *)l3_hdr + info->l3_len);
+               /* do not recalculate udp cksum if it was 0 */
+               if (udp_hdr->dgram_cksum != 0) {
+                       udp_hdr->dgram_cksum = 0;
+                       if (testpmd_ol_flags & TESTPMD_TX_OFFLOAD_UDP_CKSUM) {
+                               ol_flags |= PKT_TX_UDP_CKSUM;
+                               udp_hdr->dgram_cksum = get_psd_sum(l3_hdr,
+                                       info->ethertype, ol_flags);
+                       } else {
+                               udp_hdr->dgram_cksum =
+                                       get_udptcp_checksum(l3_hdr, udp_hdr,
+                                               info->ethertype);
+                       }
+               }
+       } else if (info->l4_proto == IPPROTO_TCP) {
+               tcp_hdr = (struct tcp_hdr *)((char *)l3_hdr + info->l3_len);
+               tcp_hdr->cksum = 0;
+               if (info->tso_segsz != 0) {
+                       ol_flags |= PKT_TX_TCP_SEG;
+                       tcp_hdr->cksum = get_psd_sum(l3_hdr, info->ethertype,
+                               ol_flags);
+               } else if (testpmd_ol_flags & TESTPMD_TX_OFFLOAD_TCP_CKSUM) {
+                       ol_flags |= PKT_TX_TCP_CKSUM;
+                       tcp_hdr->cksum = get_psd_sum(l3_hdr, info->ethertype,
+                               ol_flags);
+               } else {
+                       tcp_hdr->cksum =
+                               get_udptcp_checksum(l3_hdr, tcp_hdr,
+                                       info->ethertype);
+               }
+       } else if (info->l4_proto == IPPROTO_SCTP) {
+               sctp_hdr = (struct sctp_hdr *)((char *)l3_hdr + info->l3_len);
+               sctp_hdr->cksum = 0;
+               /* sctp payload must be a multiple of 4 to be
+                * offloaded */
+               if ((testpmd_ol_flags & TESTPMD_TX_OFFLOAD_SCTP_CKSUM) &&
+                       ((ipv4_hdr->total_length & 0x3) == 0)) {
+                       ol_flags |= PKT_TX_SCTP_CKSUM;
+               } else {
+                       /* XXX implement CRC32c, example available in
+                        * RFC3309 */
+               }
+       }
+
+       return ol_flags;
+}
+
+/* Calculate the checksum of outer header (only vxlan is supported,
+ * meaning IP + UDP). The caller already checked that it's a vxlan
+ * packet */
+static uint64_t
+process_outer_cksums(void *outer_l3_hdr, struct testpmd_offload_info *info,
+       uint16_t testpmd_ol_flags)
+{
+       struct ipv4_hdr *ipv4_hdr = outer_l3_hdr;
+       struct ipv6_hdr *ipv6_hdr = outer_l3_hdr;
+       struct udp_hdr *udp_hdr;
+       uint64_t ol_flags = 0;
+
+       if (info->outer_ethertype == _htons(ETHER_TYPE_IPv4)) {
+               ipv4_hdr->hdr_checksum = 0;
+               ol_flags |= PKT_TX_OUTER_IPV4;
+
+               if (testpmd_ol_flags & TESTPMD_TX_OFFLOAD_OUTER_IP_CKSUM)
+                       ol_flags |= PKT_TX_OUTER_IP_CKSUM;
+               else
+                       ipv4_hdr->hdr_checksum = rte_ipv4_cksum(ipv4_hdr);
+       } else if (testpmd_ol_flags & TESTPMD_TX_OFFLOAD_OUTER_IP_CKSUM)
+               ol_flags |= PKT_TX_OUTER_IPV6;
+
+       if (info->outer_l4_proto != IPPROTO_UDP)
+               return ol_flags;
+
+       /* outer UDP checksum is always done in software as we have no
+        * hardware supporting it today, and no API for it. */
+
+       udp_hdr = (struct udp_hdr *)((char *)outer_l3_hdr + info->outer_l3_len);
+       /* do not recalculate udp cksum if it was 0 */
+       if (udp_hdr->dgram_cksum != 0) {
+               udp_hdr->dgram_cksum = 0;
+               if (info->outer_ethertype == _htons(ETHER_TYPE_IPv4))
+                       udp_hdr->dgram_cksum =
+                               rte_ipv4_udptcp_cksum(ipv4_hdr, udp_hdr);
+               else
+                       udp_hdr->dgram_cksum =
+                               rte_ipv6_udptcp_cksum(ipv6_hdr, udp_hdr);
+       }
+
+       return ol_flags;
+}
+
+/*
+ * Helper function.
+ * Performs actual copying.
+ * Returns number of segments in the destination mbuf on success,
+ * or negative error code on failure.
+ */
+static int
+mbuf_copy_split(const struct rte_mbuf *ms, struct rte_mbuf *md[],
+       uint16_t seglen[], uint8_t nb_seg)
+{
+       uint32_t dlen, slen, tlen;
+       uint32_t i, len;
+       const struct rte_mbuf *m;
+       const uint8_t *src;
+       uint8_t *dst;
+
+       dlen = 0;
+       slen = 0;
+       tlen = 0;
+
+       dst = NULL;
+       src = NULL;
+
+       m = ms;
+       i = 0;
+       while (ms != NULL && i != nb_seg) {
+
+               if (slen == 0) {
+                       slen = rte_pktmbuf_data_len(ms);
+                       src = rte_pktmbuf_mtod(ms, const uint8_t *);
+               }
+
+               if (dlen == 0) {
+                       dlen = RTE_MIN(seglen[i], slen);
+                       md[i]->data_len = dlen;
+                       md[i]->next = (i + 1 == nb_seg) ? NULL : md[i + 1];
+                       dst = rte_pktmbuf_mtod(md[i], uint8_t *);
+               }
+
+               len = RTE_MIN(slen, dlen);
+               memcpy(dst, src, len);
+               tlen += len;
+               slen -= len;
+               dlen -= len;
+               src += len;
+               dst += len;
+
+               if (slen == 0)
+                       ms = ms->next;
+               if (dlen == 0)
+                       i++;
+       }
+
+       if (ms != NULL)
+               return -ENOBUFS;
+       else if (tlen != m->pkt_len)
+               return -EINVAL;
+
+       md[0]->nb_segs = nb_seg;
+       md[0]->pkt_len = tlen;
+       md[0]->vlan_tci = m->vlan_tci;
+       md[0]->vlan_tci_outer = m->vlan_tci_outer;
+       md[0]->ol_flags = m->ol_flags;
+       md[0]->tx_offload = m->tx_offload;
+
+       return nb_seg;
+}
+
+/*
+ * Allocate a new mbuf with up to tx_pkt_nb_segs segments.
+ * Copy packet contents and offload information into then new segmented mbuf.
+ */
+static struct rte_mbuf *
+pkt_copy_split(const struct rte_mbuf *pkt)
+{
+       int32_t n, rc;
+       uint32_t i, len, nb_seg;
+       struct rte_mempool *mp;
+       uint16_t seglen[RTE_MAX_SEGS_PER_PKT];
+       struct rte_mbuf *p, *md[RTE_MAX_SEGS_PER_PKT];
+
+       mp = current_fwd_lcore()->mbp;
+
+       if (tx_pkt_split == TX_PKT_SPLIT_RND)
+               nb_seg = random() % tx_pkt_nb_segs + 1;
+       else
+               nb_seg = tx_pkt_nb_segs;
+
+       memcpy(seglen, tx_pkt_seg_lengths, nb_seg * sizeof(seglen[0]));
+
+       /* calculate number of segments to use and their length. */
+       len = 0;
+       for (i = 0; i != nb_seg && len < pkt->pkt_len; i++) {
+               len += seglen[i];
+               md[i] = NULL;
+       }
+
+       n = pkt->pkt_len - len;
+
+       /* update size of the last segment to fit rest of the packet */
+       if (n >= 0) {
+               seglen[i - 1] += n;
+               len += n;
+       }
+
+       nb_seg = i;
+       while (i != 0) {
+               p = rte_pktmbuf_alloc(mp);
+               if (p == NULL) {
+                       RTE_LOG(ERR, USER1,
+                               "failed to allocate %u-th of %u mbuf "
+                               "from mempool: %s\n",
+                               nb_seg - i, nb_seg, mp->name);
+                       break;
+               }
+
+               md[--i] = p;
+               if (rte_pktmbuf_tailroom(md[i]) < seglen[i]) {
+                       RTE_LOG(ERR, USER1, "mempool %s, %u-th segment: "
+                               "expected seglen: %u, "
+                               "actual mbuf tailroom: %u\n",
+                               mp->name, i, seglen[i],
+                               rte_pktmbuf_tailroom(md[i]));
+                       break;
+               }
+       }
+
+       /* all mbufs successfully allocated, do copy */
+       if (i == 0) {
+               rc = mbuf_copy_split(pkt, md, seglen, nb_seg);
+               if (rc < 0)
+                       RTE_LOG(ERR, USER1,
+                               "mbuf_copy_split for %p(len=%u, nb_seg=%hhu) "
+                               "into %u segments failed with error code: %d\n",
+                               pkt, pkt->pkt_len, pkt->nb_segs, nb_seg, rc);
+
+               /* figure out how many mbufs to free. */
+               i = RTE_MAX(rc, 0);
+       }
+
+       /* free unused mbufs */
+       for (; i != nb_seg; i++) {
+               rte_pktmbuf_free_seg(md[i]);
+               md[i] = NULL;
+       }
+
+       return md[0];
+}
+
+/*
+ * Receive a burst of packets, and for each packet:
+ *  - parse packet, and try to recognize a supported packet type (1)
+ *  - if it's not a supported packet type, don't touch the packet, else:
+ *  - modify the IPs in inner headers and in outer headers if any
+ *  - reprocess the checksum of all supported layers. This is done in SW
+ *    or HW, depending on testpmd command line configuration
+ *  - if TSO is enabled in testpmd command line, also flag the mbuf for TCP
+ *    segmentation offload (this implies HW TCP checksum)
+ * Then transmit packets on the output port.
+ *
+ * (1) Supported packets are:
+ *   Ether / (vlan) / IP|IP6 / UDP|TCP|SCTP .
+ *   Ether / (vlan) / outer IP|IP6 / outer UDP / VxLAN / Ether / IP|IP6 /
+ *           UDP|TCP|SCTP
+ *   Ether / (vlan) / outer IP|IP6 / GRE / Ether / IP|IP6 / UDP|TCP|SCTP
+ *   Ether / (vlan) / outer IP|IP6 / GRE / IP|IP6 / UDP|TCP|SCTP
+ *   Ether / (vlan) / outer IP|IP6 / IP|IP6 / UDP|TCP|SCTP
+ *
+ * The testpmd command line for this forward engine sets the flags
+ * TESTPMD_TX_OFFLOAD_* in ports[tx_port].tx_ol_flags. They control
+ * wether a checksum must be calculated in software or in hardware. The
+ * IP, UDP, TCP and SCTP flags always concern the inner layer. The
+ * OUTER_IP is only useful for tunnel packets.
+ */
+static void
+pkt_burst_checksum_forward(struct fwd_stream *fs)
+{
+       struct rte_mbuf *pkts_burst[MAX_PKT_BURST];
+       struct rte_port *txp;
+       struct rte_mbuf *m, *p;
+       struct ether_hdr *eth_hdr;
+       void *l3_hdr = NULL, *outer_l3_hdr = NULL; /* can be IPv4 or IPv6 */
+       uint16_t nb_rx;
+       uint16_t nb_tx;
+       uint16_t i;
+       uint64_t ol_flags;
+       uint16_t testpmd_ol_flags;
+       uint32_t rx_bad_ip_csum;
+       uint32_t rx_bad_l4_csum;
+       struct testpmd_offload_info info;
+
+#ifdef RTE_TEST_PMD_RECORD_CORE_CYCLES
+       uint64_t start_tsc;
+       uint64_t end_tsc;
+       uint64_t core_cycles;
+#endif
+
+#ifdef RTE_TEST_PMD_RECORD_CORE_CYCLES
+       start_tsc = rte_rdtsc();
+#endif
+
+       /* receive a burst of packet */
+       nb_rx = rte_eth_rx_burst(fs->rx_port, fs->rx_queue, pkts_burst,
+                                nb_pkt_per_burst);
+       if (unlikely(nb_rx == 0))
+               return;
+
+#ifdef RTE_TEST_PMD_RECORD_BURST_STATS
+       fs->rx_burst_stats.pkt_burst_spread[nb_rx]++;
+#endif
+       fs->rx_packets += nb_rx;
+       rx_bad_ip_csum = 0;
+       rx_bad_l4_csum = 0;
+
+       txp = &ports[fs->tx_port];
+       testpmd_ol_flags = txp->tx_ol_flags;
+       memset(&info, 0, sizeof(info));
+       info.tso_segsz = txp->tso_segsz;
+
+       for (i = 0; i < nb_rx; i++) {
+
+               ol_flags = 0;
+               info.is_tunnel = 0;
+               m = pkts_burst[i];
+
+               /* Update the L3/L4 checksum error packet statistics */
+               rx_bad_ip_csum += ((m->ol_flags & PKT_RX_IP_CKSUM_BAD) != 0);
+               rx_bad_l4_csum += ((m->ol_flags & PKT_RX_L4_CKSUM_BAD) != 0);
+
+               /* step 1: dissect packet, parsing optional vlan, ip4/ip6, vxlan
+                * and inner headers */
+
+               eth_hdr = rte_pktmbuf_mtod(m, struct ether_hdr *);
+               ether_addr_copy(&peer_eth_addrs[fs->peer_addr],
+                               &eth_hdr->d_addr);
+               ether_addr_copy(&ports[fs->tx_port].eth_addr,
+                               &eth_hdr->s_addr);
+               parse_ethernet(eth_hdr, &info);
+               l3_hdr = (char *)eth_hdr + info.l2_len;
+
+               /* check if it's a supported tunnel */
+               if (testpmd_ol_flags & TESTPMD_TX_OFFLOAD_PARSE_TUNNEL) {
+                       if (info.l4_proto == IPPROTO_UDP) {
+                               struct udp_hdr *udp_hdr;
+                               udp_hdr = (struct udp_hdr *)((char *)l3_hdr +
+                                       info.l3_len);
+                               parse_vxlan(udp_hdr, &info, m->packet_type);
+                       } else if (info.l4_proto == IPPROTO_GRE) {
+                               struct simple_gre_hdr *gre_hdr;
+                               gre_hdr = (struct simple_gre_hdr *)
+                                       ((char *)l3_hdr + info.l3_len);
+                               parse_gre(gre_hdr, &info);
+                       } else if (info.l4_proto == IPPROTO_IPIP) {
+                               void *encap_ip_hdr;
+                               encap_ip_hdr = (char *)l3_hdr + info.l3_len;
+                               parse_encap_ip(encap_ip_hdr, &info);
+                       }
+               }
+
+               /* update l3_hdr and outer_l3_hdr if a tunnel was parsed */
+               if (info.is_tunnel) {
+                       outer_l3_hdr = l3_hdr;
+                       l3_hdr = (char *)l3_hdr + info.outer_l3_len + info.l2_len;
+               }
+
+               /* step 2: change all source IPs (v4 or v6) so we need
+                * to recompute the chksums even if they were correct */
+
+               change_ip_addresses(l3_hdr, info.ethertype);
+               if (info.is_tunnel == 1)
+                       change_ip_addresses(outer_l3_hdr, info.outer_ethertype);
+
+               /* step 3: depending on user command line configuration,
+                * recompute checksum either in software or flag the
+                * mbuf to offload the calculation to the NIC. If TSO
+                * is configured, prepare the mbuf for TCP segmentation. */
+
+               /* process checksums of inner headers first */
+               ol_flags |= process_inner_cksums(l3_hdr, &info, testpmd_ol_flags);
+
+               /* Then process outer headers if any. Note that the software
+                * checksum will be wrong if one of the inner checksums is
+                * processed in hardware. */
+               if (info.is_tunnel == 1) {
+                       ol_flags |= process_outer_cksums(outer_l3_hdr, &info,
+                               testpmd_ol_flags);
+               }
+
+               /* step 4: fill the mbuf meta data (flags and header lengths) */
+
+               if (info.is_tunnel == 1) {
+                       if (testpmd_ol_flags & TESTPMD_TX_OFFLOAD_OUTER_IP_CKSUM) {
+                               m->outer_l2_len = info.outer_l2_len;
+                               m->outer_l3_len = info.outer_l3_len;
+                               m->l2_len = info.l2_len;
+                               m->l3_len = info.l3_len;
+                               m->l4_len = info.l4_len;
+                       }
+                       else {
+                               /* if there is a outer UDP cksum
+                                  processed in sw and the inner in hw,
+                                  the outer checksum will be wrong as
+                                  the payload will be modified by the
+                                  hardware */
+                               m->l2_len = info.outer_l2_len +
+                                       info.outer_l3_len + info.l2_len;
+                               m->l3_len = info.l3_len;
+                               m->l4_len = info.l4_len;
+                       }
+               } else {
+                       /* this is only useful if an offload flag is
+                        * set, but it does not hurt to fill it in any
+                        * case */
+                       m->l2_len = info.l2_len;
+                       m->l3_len = info.l3_len;
+                       m->l4_len = info.l4_len;
+               }
+               m->tso_segsz = info.tso_segsz;
+               m->ol_flags = ol_flags;
+
+               /* Do split & copy for the packet. */
+               if (tx_pkt_split != TX_PKT_SPLIT_OFF) {
+                       p = pkt_copy_split(m);
+                       if (p != NULL) {
+                               rte_pktmbuf_free(m);
+                               m = p;
+                               pkts_burst[i] = m;
+                       }
+               }
+
+               /* if verbose mode is enabled, dump debug info */
+               if (verbose_level > 0) {
+                       struct {
+                               uint64_t flag;
+                               uint64_t mask;
+                       } tx_flags[] = {
+                               { PKT_TX_IP_CKSUM, PKT_TX_IP_CKSUM },
+                               { PKT_TX_UDP_CKSUM, PKT_TX_L4_MASK },
+                               { PKT_TX_TCP_CKSUM, PKT_TX_L4_MASK },
+                               { PKT_TX_SCTP_CKSUM, PKT_TX_L4_MASK },
+                               { PKT_TX_IPV4, PKT_TX_IPV4 },
+                               { PKT_TX_IPV6, PKT_TX_IPV6 },
+                               { PKT_TX_OUTER_IP_CKSUM, PKT_TX_OUTER_IP_CKSUM },
+                               { PKT_TX_OUTER_IPV4, PKT_TX_OUTER_IPV4 },
+                               { PKT_TX_OUTER_IPV6, PKT_TX_OUTER_IPV6 },
+                               { PKT_TX_TCP_SEG, PKT_TX_TCP_SEG },
+                       };
+                       unsigned j;
+                       const char *name;
+
+                       printf("-----------------\n");
+                       printf("mbuf=%p, pkt_len=%u, nb_segs=%hhu:\n",
+                               m, m->pkt_len, m->nb_segs);
+                       /* dump rx parsed packet info */
+                       printf("rx: l2_len=%d ethertype=%x l3_len=%d "
+                               "l4_proto=%d l4_len=%d\n",
+                               info.l2_len, rte_be_to_cpu_16(info.ethertype),
+                               info.l3_len, info.l4_proto, info.l4_len);
+                       if (info.is_tunnel == 1)
+                               printf("rx: outer_l2_len=%d outer_ethertype=%x "
+                                       "outer_l3_len=%d\n", info.outer_l2_len,
+                                       rte_be_to_cpu_16(info.outer_ethertype),
+                                       info.outer_l3_len);
+                       /* dump tx packet info */
+                       if ((testpmd_ol_flags & (TESTPMD_TX_OFFLOAD_IP_CKSUM |
+                                               TESTPMD_TX_OFFLOAD_UDP_CKSUM |
+                                               TESTPMD_TX_OFFLOAD_TCP_CKSUM |
+                                               TESTPMD_TX_OFFLOAD_SCTP_CKSUM)) ||
+                               info.tso_segsz != 0)
+                               printf("tx: m->l2_len=%d m->l3_len=%d "
+                                       "m->l4_len=%d\n",
+                                       m->l2_len, m->l3_len, m->l4_len);
+                       if ((info.is_tunnel == 1) &&
+                               (testpmd_ol_flags & TESTPMD_TX_OFFLOAD_OUTER_IP_CKSUM))
+                               printf("tx: m->outer_l2_len=%d m->outer_l3_len=%d\n",
+                                       m->outer_l2_len, m->outer_l3_len);
+                       if (info.tso_segsz != 0)
+                               printf("tx: m->tso_segsz=%d\n", m->tso_segsz);
+                       printf("tx: flags=");
+                       for (j = 0; j < sizeof(tx_flags)/sizeof(*tx_flags); j++) {
+                               name = rte_get_tx_ol_flag_name(tx_flags[j].flag);
+                               if ((m->ol_flags & tx_flags[j].mask) ==
+                                       tx_flags[j].flag)
+                                       printf("%s ", name);
+                       }
+                       printf("\n");
+               }
+       }
+       nb_tx = rte_eth_tx_burst(fs->tx_port, fs->tx_queue, pkts_burst, nb_rx);
+       fs->tx_packets += nb_tx;
+       fs->rx_bad_ip_csum += rx_bad_ip_csum;
+       fs->rx_bad_l4_csum += rx_bad_l4_csum;
+
+#ifdef RTE_TEST_PMD_RECORD_BURST_STATS
+       fs->tx_burst_stats.pkt_burst_spread[nb_tx]++;
+#endif
+       if (unlikely(nb_tx < nb_rx)) {
+               fs->fwd_dropped += (nb_rx - nb_tx);
+               do {
+                       rte_pktmbuf_free(pkts_burst[nb_tx]);
+               } while (++nb_tx < nb_rx);
+       }
+#ifdef RTE_TEST_PMD_RECORD_CORE_CYCLES
+       end_tsc = rte_rdtsc();
+       core_cycles = (end_tsc - start_tsc);
+       fs->core_cycles = (uint64_t) (fs->core_cycles + core_cycles);
+#endif
+}
+
+struct fwd_engine csum_fwd_engine = {
+       .fwd_mode_name  = "csum",
+       .port_fwd_begin = NULL,
+       .port_fwd_end   = NULL,
+       .packet_fwd     = pkt_burst_checksum_forward,
+};