[PATCH 5/8] net: fix outer UDP checksum in Intel prepare helper

[David Marchand <david.marchand@redhat.com>]

Setting a pseudo header checksum in the outer UDP checksum is a Intel
(and some other vendors) requirement.
Applications (like OVS) requesting outer UDP checksum without doing this
extra setup have broken outer UDP checksums.

Move this specific setup from testpmd to the "common" helper
rte_net_intel_cksum_flags_prepare().

net/hns3 can then be adjusted.

Bugzilla ID: 1406
Fixes: d8e5e69f3a9b ("app/testpmd: add GTP parsing and Tx checksum offload")
Cc: stable@dpdk.org

Signed-off-by: David Marchand <david.marchand@redhat.com>
---
 app/test-pmd/csumonly.c      | 11 +----
 drivers/net/hns3/hns3_rxtx.c | 93 ++++++++++--------------------------
 lib/net/rte_net.h            | 18 ++++++-
 3 files changed, 44 insertions(+), 78 deletions(-)

diff --git a/app/test-pmd/csumonly.c b/app/test-pmd/csumonly.c
index f5125c2788..71add6ca47 100644
--- a/app/test-pmd/csumonly.c
+++ b/app/test-pmd/csumonly.c
@@ -577,8 +577,6 @@ static uint64_t
 process_outer_cksums(void *outer_l3_hdr, struct testpmd_offload_info *info,
 	uint64_t tx_offloads, int tso_enabled, struct rte_mbuf *m)
 {
-	struct rte_ipv4_hdr *ipv4_hdr = outer_l3_hdr;
-	struct rte_ipv6_hdr *ipv6_hdr = outer_l3_hdr;
 	struct rte_udp_hdr *udp_hdr;
 	uint64_t ol_flags = 0;
 
@@ -588,6 +586,8 @@ process_outer_cksums(void *outer_l3_hdr, struct testpmd_offload_info *info,
 		if (tx_offloads	& RTE_ETH_TX_OFFLOAD_OUTER_IPV4_CKSUM) {
 			ol_flags |= RTE_MBUF_F_TX_OUTER_IP_CKSUM;
 		} else {
+			struct rte_ipv4_hdr *ipv4_hdr = outer_l3_hdr;
+
 			ipv4_hdr->hdr_checksum = 0;
 			ipv4_hdr->hdr_checksum = rte_ipv4_cksum(ipv4_hdr);
 		}
@@ -608,13 +608,6 @@ process_outer_cksums(void *outer_l3_hdr, struct testpmd_offload_info *info,
 
 	/* Skip SW outer UDP checksum generation if HW supports it */
 	if (tx_offloads & RTE_ETH_TX_OFFLOAD_OUTER_UDP_CKSUM) {
-		if (info->outer_ethertype == _htons(RTE_ETHER_TYPE_IPV4))
-			udp_hdr->dgram_cksum
-				= rte_ipv4_phdr_cksum(ipv4_hdr, ol_flags);
-		else
-			udp_hdr->dgram_cksum
-				= rte_ipv6_phdr_cksum(ipv6_hdr, ol_flags);
-
 		ol_flags |= RTE_MBUF_F_TX_OUTER_UDP_CKSUM;
 		return ol_flags;
 	}
diff --git a/drivers/net/hns3/hns3_rxtx.c b/drivers/net/hns3/hns3_rxtx.c
index 7e636a0a2e..03fc919fd7 100644
--- a/drivers/net/hns3/hns3_rxtx.c
+++ b/drivers/net/hns3/hns3_rxtx.c
@@ -3616,58 +3616,6 @@ hns3_pkt_need_linearized(struct rte_mbuf *tx_pkts, uint32_t bd_num,
 	return false;
 }
 
-static bool
-hns3_outer_ipv4_cksum_prepared(struct rte_mbuf *m, uint64_t ol_flags,
-				uint32_t *l4_proto)
-{
-	struct rte_ipv4_hdr *ipv4_hdr;
-	ipv4_hdr = rte_pktmbuf_mtod_offset(m, struct rte_ipv4_hdr *,
-					   m->outer_l2_len);
-	if (ol_flags & RTE_MBUF_F_TX_OUTER_IP_CKSUM)
-		ipv4_hdr->hdr_checksum = 0;
-	if (ol_flags & RTE_MBUF_F_TX_OUTER_UDP_CKSUM) {
-		struct rte_udp_hdr *udp_hdr;
-		/*
-		 * If OUTER_UDP_CKSUM is support, HW can calculate the pseudo
-		 * header for TSO packets
-		 */
-		if (ol_flags & RTE_MBUF_F_TX_TCP_SEG)
-			return true;
-		udp_hdr = rte_pktmbuf_mtod_offset(m, struct rte_udp_hdr *,
-				m->outer_l2_len + m->outer_l3_len);
-		udp_hdr->dgram_cksum = rte_ipv4_phdr_cksum(ipv4_hdr, ol_flags);
-
-		return true;
-	}
-	*l4_proto = ipv4_hdr->next_proto_id;
-	return false;
-}
-
-static bool
-hns3_outer_ipv6_cksum_prepared(struct rte_mbuf *m, uint64_t ol_flags,
-				uint32_t *l4_proto)
-{
-	struct rte_ipv6_hdr *ipv6_hdr;
-	ipv6_hdr = rte_pktmbuf_mtod_offset(m, struct rte_ipv6_hdr *,
-					   m->outer_l2_len);
-	if (ol_flags & RTE_MBUF_F_TX_OUTER_UDP_CKSUM) {
-		struct rte_udp_hdr *udp_hdr;
-		/*
-		 * If OUTER_UDP_CKSUM is support, HW can calculate the pseudo
-		 * header for TSO packets
-		 */
-		if (ol_flags & RTE_MBUF_F_TX_TCP_SEG)
-			return true;
-		udp_hdr = rte_pktmbuf_mtod_offset(m, struct rte_udp_hdr *,
-				m->outer_l2_len + m->outer_l3_len);
-		udp_hdr->dgram_cksum = rte_ipv6_phdr_cksum(ipv6_hdr, ol_flags);
-
-		return true;
-	}
-	*l4_proto = ipv6_hdr->proto;
-	return false;
-}
-
 static void
 hns3_outer_header_cksum_prepare(struct rte_mbuf *m)
 {
@@ -3675,29 +3623,38 @@ hns3_outer_header_cksum_prepare(struct rte_mbuf *m)
 	uint32_t paylen, hdr_len, l4_proto;
 	struct rte_udp_hdr *udp_hdr;
 
-	if (!(ol_flags & (RTE_MBUF_F_TX_OUTER_IPV4 | RTE_MBUF_F_TX_OUTER_IPV6)))
+	if (!(ol_flags & (RTE_MBUF_F_TX_OUTER_IPV4 | RTE_MBUF_F_TX_OUTER_IPV6)) &&
+			((ol_flags & RTE_MBUF_F_TX_OUTER_UDP_CKSUM) ||
+			!(ol_flags & RTE_MBUF_F_TX_TCP_SEG)))
 		return;
 
 	if (ol_flags & RTE_MBUF_F_TX_OUTER_IPV4) {
-		if (hns3_outer_ipv4_cksum_prepared(m, ol_flags, &l4_proto))
-			return;
+		struct rte_ipv4_hdr *ipv4_hdr;
+
+		ipv4_hdr = rte_pktmbuf_mtod_offset(m, struct rte_ipv4_hdr *,
+			m->outer_l2_len);
+		l4_proto = ipv4_hdr->next_proto_id;
 	} else {
-		if (hns3_outer_ipv6_cksum_prepared(m, ol_flags, &l4_proto))
-			return;
+		struct rte_ipv6_hdr *ipv6_hdr;
+
+		ipv6_hdr = rte_pktmbuf_mtod_offset(m, struct rte_ipv6_hdr *,
+					   m->outer_l2_len);
+		l4_proto = ipv6_hdr->proto;
 	}
 
+	if (l4_proto != IPPROTO_UDP)
+		return;
+
 	/* driver should ensure the outer udp cksum is 0 for TUNNEL TSO */
-	if (l4_proto == IPPROTO_UDP && (ol_flags & RTE_MBUF_F_TX_TCP_SEG)) {
-		hdr_len = m->l2_len + m->l3_len + m->l4_len;
-		hdr_len += m->outer_l2_len + m->outer_l3_len;
-		paylen = m->pkt_len - hdr_len;
-		if (paylen <= m->tso_segsz)
-			return;
-		udp_hdr = rte_pktmbuf_mtod_offset(m, struct rte_udp_hdr *,
-						  m->outer_l2_len +
-						  m->outer_l3_len);
-		udp_hdr->dgram_cksum = 0;
-	}
+	hdr_len = m->l2_len + m->l3_len + m->l4_len;
+	hdr_len += m->outer_l2_len + m->outer_l3_len;
+	paylen = m->pkt_len - hdr_len;
+	if (paylen <= m->tso_segsz)
+		return;
+	udp_hdr = rte_pktmbuf_mtod_offset(m, struct rte_udp_hdr *,
+					  m->outer_l2_len +
+					  m->outer_l3_len);
+	udp_hdr->dgram_cksum = 0;
 }
 
 static int
diff --git a/lib/net/rte_net.h b/lib/net/rte_net.h
index ef3ff4c6fd..efd9d5f5ee 100644
--- a/lib/net/rte_net.h
+++ b/lib/net/rte_net.h
@@ -121,7 +121,8 @@ rte_net_intel_cksum_flags_prepare(struct rte_mbuf *m, uint64_t ol_flags)
 	 * no offloads are requested.
 	 */
 	if (!(ol_flags & (RTE_MBUF_F_TX_IP_CKSUM | RTE_MBUF_F_TX_L4_MASK | RTE_MBUF_F_TX_TCP_SEG |
-					RTE_MBUF_F_TX_UDP_SEG | RTE_MBUF_F_TX_OUTER_IP_CKSUM)))
+					RTE_MBUF_F_TX_UDP_SEG | RTE_MBUF_F_TX_OUTER_IP_CKSUM |
+					RTE_MBUF_F_TX_OUTER_UDP_CKSUM)))
 		return 0;
 
 	if (ol_flags & (RTE_MBUF_F_TX_OUTER_IPV4 | RTE_MBUF_F_TX_OUTER_IPV6)) {
@@ -135,6 +136,21 @@ rte_net_intel_cksum_flags_prepare(struct rte_mbuf *m, uint64_t ol_flags)
 					struct rte_ipv4_hdr *, m->outer_l2_len);
 			ipv4_hdr->hdr_checksum = 0;
 		}
+		if (ol_flags & RTE_MBUF_F_TX_OUTER_UDP_CKSUM) {
+			if (ol_flags & RTE_MBUF_F_TX_OUTER_IPV4) {
+				ipv4_hdr = rte_pktmbuf_mtod_offset(m, struct rte_ipv4_hdr *,
+					m->outer_l2_len);
+				udp_hdr = (struct rte_udp_hdr *)((char *)ipv4_hdr +
+					m->outer_l3_len);
+				udp_hdr->dgram_cksum = rte_ipv4_phdr_cksum(ipv4_hdr, m->ol_flags);
+			} else {
+				ipv6_hdr = rte_pktmbuf_mtod_offset(m, struct rte_ipv6_hdr *,
+					m->outer_l2_len);
+				udp_hdr = rte_pktmbuf_mtod_offset(m, struct rte_udp_hdr *,
+					 m->outer_l2_len + m->outer_l3_len);
+				udp_hdr->dgram_cksum = rte_ipv6_phdr_cksum(ipv6_hdr, m->ol_flags);
+			}
+		}
 	}
 
 	/*
-- 
2.44.0