[PATCH 5/5] net/mlx5: fix GRE protocol type translation

[Gregory Etelson <getelson@nvidia.com>]

When application creates several flows to match on GRE tunnel
without explicitly specifying GRE protocol type value in
flow rules, PMD will translate that to zero mask.
RDMA-CORE cannot distinguish between different inner flow types and
produces identical matchers for each zero mask.

The patch extracts inner header type from flow rule and forces it
in GRE protocol type, if application did not specify
any without explicitly specifying GRE protocol type value in
flow rules, protocol type value.

Cc: stable@dpdk.org

Fixes: fc2c498ccb94 ("net/mlx5: add Direct Verbs translate items")

Signed-off-by: Gregory Etelson <getelson@nvidia.com>
---
 drivers/net/mlx5/mlx5_flow_dv.c | 70 +++++++++++++++++++--------------
 1 file changed, 40 insertions(+), 30 deletions(-)

diff --git a/drivers/net/mlx5/mlx5_flow_dv.c b/drivers/net/mlx5/mlx5_flow_dv.c
index bce504391d..287a17d956 100644
--- a/drivers/net/mlx5/mlx5_flow_dv.c
+++ b/drivers/net/mlx5/mlx5_flow_dv.c
@@ -8730,18 +8730,19 @@ flow_dv_translate_item_gre_key(void *matcher, void *key,
  *   Flow matcher value.
  * @param[in] item
  *   Flow pattern to translate.
- * @param[in] inner
- *   Item is inner pattern.
+ * @param[in] pattern_flags
+ *   Accumulated pattern flags.
  */
 static void
 flow_dv_translate_item_gre(void *matcher, void *key,
 			   const struct rte_flow_item *item,
-			   int inner)
+			   uint64_t pattern_flags)
 {
+	static const struct rte_flow_item_gre empty_gre = {0,};
 	const struct rte_flow_item_gre *gre_m = item->mask;
 	const struct rte_flow_item_gre *gre_v = item->spec;
-	void *headers_m;
-	void *headers_v;
+	void *headers_m = MLX5_ADDR_OF(fte_match_param, matcher, outer_headers);
+	void *headers_v = MLX5_ADDR_OF(fte_match_param, key, outer_headers);
 	void *misc_m = MLX5_ADDR_OF(fte_match_param, matcher, misc_parameters);
 	void *misc_v = MLX5_ADDR_OF(fte_match_param, key, misc_parameters);
 	struct {
@@ -8758,26 +8759,17 @@ flow_dv_translate_item_gre(void *matcher, void *key,
 			uint16_t value;
 		};
 	} gre_crks_rsvd0_ver_m, gre_crks_rsvd0_ver_v;
+	uint16_t protocol_m, protocol_v;
 
-	if (inner) {
-		headers_m = MLX5_ADDR_OF(fte_match_param, matcher,
-					 inner_headers);
-		headers_v = MLX5_ADDR_OF(fte_match_param, key, inner_headers);
-	} else {
-		headers_m = MLX5_ADDR_OF(fte_match_param, matcher,
-					 outer_headers);
-		headers_v = MLX5_ADDR_OF(fte_match_param, key, outer_headers);
-	}
 	MLX5_SET(fte_match_set_lyr_2_4, headers_m, ip_protocol, 0xff);
 	MLX5_SET(fte_match_set_lyr_2_4, headers_v, ip_protocol, IPPROTO_GRE);
-	if (!gre_v)
-		return;
-	if (!gre_m)
-		gre_m = &rte_flow_item_gre_mask;
-	MLX5_SET(fte_match_set_misc, misc_m, gre_protocol,
-		 rte_be_to_cpu_16(gre_m->protocol));
-	MLX5_SET(fte_match_set_misc, misc_v, gre_protocol,
-		 rte_be_to_cpu_16(gre_v->protocol & gre_m->protocol));
+	if (!gre_v) {
+		gre_v = &empty_gre;
+		gre_m = &empty_gre;
+	} else {
+		if (!gre_m)
+			gre_m = &rte_flow_item_gre_mask;
+	}
 	gre_crks_rsvd0_ver_m.value = rte_be_to_cpu_16(gre_m->c_rsvd0_ver);
 	gre_crks_rsvd0_ver_v.value = rte_be_to_cpu_16(gre_v->c_rsvd0_ver);
 	MLX5_SET(fte_match_set_misc, misc_m, gre_c_present,
@@ -8795,6 +8787,16 @@ flow_dv_translate_item_gre(void *matcher, void *key,
 	MLX5_SET(fte_match_set_misc, misc_v, gre_s_present,
 		 gre_crks_rsvd0_ver_v.s_present &
 		 gre_crks_rsvd0_ver_m.s_present);
+	protocol_m = rte_be_to_cpu_16(gre_m->protocol);
+	protocol_v = rte_be_to_cpu_16(gre_v->protocol);
+	if (!protocol_m) {
+		/* Force next protocol to prevent matchers duplication */
+		protocol_m = 0xFFFF;
+		protocol_v = mlx5_translate_tunnel_etypes(pattern_flags);
+	}
+	MLX5_SET(fte_match_set_misc, misc_m, gre_protocol, protocol_m);
+	MLX5_SET(fte_match_set_misc, misc_v, gre_protocol,
+		 protocol_m & protocol_v);
 }
 
 /**
@@ -8806,13 +8808,13 @@ flow_dv_translate_item_gre(void *matcher, void *key,
  *   Flow matcher value.
  * @param[in] item
  *   Flow pattern to translate.
- * @param[in] inner
- *   Item is inner pattern.
+ * @param[in] pattern_flags
+ *   Accumulated pattern flags.
  */
 static void
 flow_dv_translate_item_nvgre(void *matcher, void *key,
 			     const struct rte_flow_item *item,
-			     int inner)
+			     unsigned long pattern_flags)
 {
 	const struct rte_flow_item_nvgre *nvgre_m = item->mask;
 	const struct rte_flow_item_nvgre *nvgre_v = item->spec;
@@ -8839,7 +8841,7 @@ flow_dv_translate_item_nvgre(void *matcher, void *key,
 		.mask = &gre_mask,
 		.last = NULL,
 	};
-	flow_dv_translate_item_gre(matcher, key, &gre_item, inner);
+	flow_dv_translate_item_gre(matcher, key, &gre_item, pattern_flags);
 	if (!nvgre_v)
 		return;
 	if (!nvgre_m)
@@ -13434,10 +13436,9 @@ flow_dv_translate(struct rte_eth_dev *dev,
 					     MLX5_FLOW_LAYER_OUTER_L4_UDP;
 			break;
 		case RTE_FLOW_ITEM_TYPE_GRE:
-			flow_dv_translate_item_gre(match_mask, match_value,
-						   items, tunnel);
 			matcher.priority = MLX5_TUNNEL_PRIO_GET(rss_desc);
 			last_item = MLX5_FLOW_LAYER_GRE;
+			tunnel_item = items;
 			break;
 		case RTE_FLOW_ITEM_TYPE_GRE_KEY:
 			flow_dv_translate_item_gre_key(match_mask,
@@ -13445,10 +13446,9 @@ flow_dv_translate(struct rte_eth_dev *dev,
 			last_item = MLX5_FLOW_LAYER_GRE_KEY;
 			break;
 		case RTE_FLOW_ITEM_TYPE_NVGRE:
-			flow_dv_translate_item_nvgre(match_mask, match_value,
-						     items, tunnel);
 			matcher.priority = MLX5_TUNNEL_PRIO_GET(rss_desc);
 			last_item = MLX5_FLOW_LAYER_GRE;
+			tunnel_item = items;
 			break;
 		case RTE_FLOW_ITEM_TYPE_VXLAN:
 			flow_dv_translate_item_vxlan(dev, attr,
@@ -13597,6 +13597,16 @@ flow_dv_translate(struct rte_eth_dev *dev,
 	else if (item_flags & MLX5_FLOW_LAYER_GENEVE)
 		flow_dv_translate_item_geneve(match_mask, match_value,
 					      tunnel_item, item_flags);
+	else if (item_flags & MLX5_FLOW_LAYER_GRE) {
+		if (tunnel_item->type == RTE_FLOW_ITEM_TYPE_GRE)
+			flow_dv_translate_item_gre(match_mask, match_value,
+						   tunnel_item, item_flags);
+		else if (tunnel_item->type == RTE_FLOW_ITEM_TYPE_NVGRE)
+			flow_dv_translate_item_nvgre(match_mask, match_value,
+						     tunnel_item, item_flags);
+		else
+			MLX5_ASSERT(false);
+	}
 #ifdef RTE_LIBRTE_MLX5_DEBUG
 	MLX5_ASSERT(!flow_dv_check_valid_spec(matcher.mask.buf,
 					      dev_flow->dv.value.buf));
-- 
2.33.1