[dpdk-dev] [PATCH v2] net/mlx5: fix match on Ethertype and CVLAN tag

[Dekel Peled <dekelp@mellanox.com>]

HW supports match on one Ethertype, the Ethertype following the last
VLAN tag of the packet (see PRM).
Previous patch added specific handling for packets with VLAN tag,
after setting match on Ethertype.

This patch moves the handling of packets with VLAN tag, to be done
before and instead of setting match on Ethertype.

Previous patch also added, as part of specific handling for packets
with VLAN tag, the setting of cvlan_tag mask bit in translation of
L3 items.
In case of L3 tunnel there is no inner L2 header, so setting this
mask bit is wrong and causes match failures.

This patch adds check to make sure L2 header exists before setting
cvlan_tag mask bit for L3 items.

Fixes: 00f75a40576b ("net/mlx5: fix VLAN match for DV mode")
Cc: stable@dpdk.org

Signed-off-by: Dekel Peled <dekelp@mellanox.com>
---
 drivers/net/mlx5/mlx5_flow_dv.c | 42 ++++++++++++++++++++++++++++++++---------
 1 file changed, 33 insertions(+), 9 deletions(-)

diff --git a/drivers/net/mlx5/mlx5_flow_dv.c b/drivers/net/mlx5/mlx5_flow_dv.c
index 467d1ce..6f15a91 100644
--- a/drivers/net/mlx5/mlx5_flow_dv.c
+++ b/drivers/net/mlx5/mlx5_flow_dv.c
@@ -5213,19 +5213,27 @@ struct field_modify_info modify_tcp[] = {
 	/* The value must be in the range of the mask. */
 	for (i = 0; i < sizeof(eth_m->dst); ++i)
 		l24_v[i] = eth_m->src.addr_bytes[i] & eth_v->src.addr_bytes[i];
-	MLX5_SET(fte_match_set_lyr_2_4, headers_m, ethertype,
-		 rte_be_to_cpu_16(eth_m->type));
-	l24_v = MLX5_ADDR_OF(fte_match_set_lyr_2_4, headers_v, ethertype);
-	*(uint16_t *)(l24_v) = eth_m->type & eth_v->type;
 	if (eth_v->type) {
 		/* When ethertype is present set mask for tagged VLAN. */
 		MLX5_SET(fte_match_set_lyr_2_4, headers_m, cvlan_tag, 1);
 		/* Set value for tagged VLAN if ethertype is 802.1Q. */
 		if (eth_v->type == RTE_BE16(RTE_ETHER_TYPE_VLAN) ||
-		    eth_v->type == RTE_BE16(RTE_ETHER_TYPE_QINQ))
+		    eth_v->type == RTE_BE16(RTE_ETHER_TYPE_QINQ)) {
 			MLX5_SET(fte_match_set_lyr_2_4, headers_v, cvlan_tag,
 				 1);
+			/* Return here to avoid setting match on ethertype. */
+			return;
+		}
 	}
+	/*
+	 * HW supports match on one Ethertype, the Ethertype following the last
+	 * VLAN tag of the packet (see PRM).
+	 * Set match on ethertype only if ETH header is not followed by VLAN.
+	 */
+	MLX5_SET(fte_match_set_lyr_2_4, headers_m, ethertype,
+		 rte_be_to_cpu_16(eth_m->type));
+	l24_v = MLX5_ADDR_OF(fte_match_set_lyr_2_4, headers_v, ethertype);
+	*(uint16_t *)(l24_v) = eth_m->type & eth_v->type;
 }
 
 /**
@@ -5299,6 +5307,8 @@ struct field_modify_info modify_tcp[] = {
  *   Flow matcher value.
  * @param[in] item
  *   Flow pattern to translate.
+ * @param[in] item_flags
+ *   Bit-fields that holds the items detected until now.
  * @param[in] inner
  *   Item is inner pattern.
  * @param[in] group
@@ -5307,6 +5317,7 @@ struct field_modify_info modify_tcp[] = {
 static void
 flow_dv_translate_item_ipv4(void *matcher, void *key,
 			    const struct rte_flow_item *item,
+			    const uint64_t item_flags,
 			    int inner, uint32_t group)
 {
 	const struct rte_flow_item_ipv4 *ipv4_m = item->mask;
@@ -5366,7 +5377,12 @@ struct field_modify_info modify_tcp[] = {
 		 ipv4_m->hdr.next_proto_id);
 	MLX5_SET(fte_match_set_lyr_2_4, headers_v, ip_protocol,
 		 ipv4_v->hdr.next_proto_id & ipv4_m->hdr.next_proto_id);
-	MLX5_SET(fte_match_set_lyr_2_4, headers_m, cvlan_tag, 1);
+	/*
+	 * On outer header (which must contains L2), or inner header with L2,
+	 * set cvlan_tag mask bit to mark this packet as untagged.
+	 */
+	if (!inner || item_flags & MLX5_FLOW_LAYER_INNER_L2)
+		MLX5_SET(fte_match_set_lyr_2_4, headers_m, cvlan_tag, 1);
 }
 
 /**
@@ -5378,6 +5394,8 @@ struct field_modify_info modify_tcp[] = {
  *   Flow matcher value.
  * @param[in] item
  *   Flow pattern to translate.
+ * @param[in] item_flags
+ *   Bit-fields that holds the items detected until now.
  * @param[in] inner
  *   Item is inner pattern.
  * @param[in] group
@@ -5386,6 +5404,7 @@ struct field_modify_info modify_tcp[] = {
 static void
 flow_dv_translate_item_ipv6(void *matcher, void *key,
 			    const struct rte_flow_item *item,
+			    const uint64_t item_flags,
 			    int inner, uint32_t group)
 {
 	const struct rte_flow_item_ipv6 *ipv6_m = item->mask;
@@ -5471,7 +5490,12 @@ struct field_modify_info modify_tcp[] = {
 		 ipv6_m->hdr.proto);
 	MLX5_SET(fte_match_set_lyr_2_4, headers_v, ip_protocol,
 		 ipv6_v->hdr.proto & ipv6_m->hdr.proto);
-	MLX5_SET(fte_match_set_lyr_2_4, headers_m, cvlan_tag, 1);
+	/*
+	 * On outer header (which must contains L2), or inner header with L2,
+	 * set cvlan_tag mask bit to mark this packet as untagged.
+	 */
+	if (!inner || item_flags & MLX5_FLOW_LAYER_INNER_L2)
+		MLX5_SET(fte_match_set_lyr_2_4, headers_m, cvlan_tag, 1);
 }
 
 /**
@@ -7574,7 +7598,7 @@ struct field_modify_info modify_tcp[] = {
 			mlx5_flow_tunnel_ip_check(items, next_protocol,
 						  &item_flags, &tunnel);
 			flow_dv_translate_item_ipv4(match_mask, match_value,
-						    items, tunnel,
+						    items, item_flags, tunnel,
 						    dev_flow->group);
 			matcher.priority = MLX5_PRIORITY_MAP_L3;
 			last_item = tunnel ? MLX5_FLOW_LAYER_INNER_L3_IPV4 :
@@ -7597,7 +7621,7 @@ struct field_modify_info modify_tcp[] = {
 			mlx5_flow_tunnel_ip_check(items, next_protocol,
 						  &item_flags, &tunnel);
 			flow_dv_translate_item_ipv6(match_mask, match_value,
-						    items, tunnel,
+						    items, item_flags, tunnel,
 						    dev_flow->group);
 			matcher.priority = MLX5_PRIORITY_MAP_L3;
 			last_item = tunnel ? MLX5_FLOW_LAYER_INNER_L3_IPV6 :
-- 
1.8.3.1