net/mlx5e: Add flow steering DMAC trap rule

Add flow group to the L2 table to hold the catch-all DMAC rule. Add API
which adds/removes DMAC trap rule. This rule catches packets that were
destined to be dropped due to no-match with previous DMAC rules. The
trap rule steer these packets to the trap tir related to the trap-RQ.

Signed-off-by: Aya Levin <ayal@nvidia.com>
Reviewed-by: Moshe Shemesh <moshe@nvidia.com>
Reviewed-by: Tariq Toukan <tariqt@nvidia.com>
Signed-off-by: Tariq Toukan <tariqt@nvidia.com>
Signed-off-by: Saeed Mahameed <saeedm@nvidia.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

drivers/net/ethernet/mellanox/mlx5/core/en/fs.h

@@ -68,6 +68,7 @@ struct mlx5e_l2_table {
 	struct hlist_head          netdev_mc[MLX5E_L2_ADDR_HASH_SIZE];
 	struct mlx5e_l2_rule	   broadcast;
 	struct mlx5e_l2_rule	   allmulti;
+	struct mlx5_flow_handle    *trap_rule;
 	bool                       broadcast_enabled;
 	bool                       allmulti_enabled;
 	bool                       promisc_enabled;
@@ -297,6 +298,8 @@ void mlx5e_destroy_flow_steering(struct mlx5e_priv *priv);
 u8 mlx5e_get_proto_by_tunnel_type(enum mlx5e_tunnel_types tt);
 int mlx5e_add_vlan_trap(struct mlx5e_priv *priv, int  trap_id, int tir_num);
 void mlx5e_remove_vlan_trap(struct mlx5e_priv *priv);
+int mlx5e_add_mac_trap(struct mlx5e_priv *priv, int  trap_id, int tir_num);
+void mlx5e_remove_mac_trap(struct mlx5e_priv *priv);
 
 #endif /* __MLX5E_FLOW_STEER_H__ */
 

drivers/net/ethernet/mellanox/mlx5/core/en_fs.c

@@ -352,6 +352,32 @@ void mlx5e_remove_vlan_trap(struct mlx5e_priv *priv)
 	}
 }
 
+int mlx5e_add_mac_trap(struct mlx5e_priv *priv, int trap_id, int tir_num)
+{
+	struct mlx5_flow_table *ft = priv->fs.l2.ft.t;
+	struct mlx5_flow_handle *rule;
+	int err;
+
+	rule = mlx5e_add_trap_rule(ft, trap_id, tir_num);
+	if (IS_ERR(rule)) {
+		err = PTR_ERR(rule);
+		priv->fs.l2.trap_rule = NULL;
+		netdev_err(priv->netdev, "%s: add MAC trap rule failed, err %d\n",
+			   __func__, err);
+		return err;
+	}
+	priv->fs.l2.trap_rule = rule;
+	return 0;
+}
+
+void mlx5e_remove_mac_trap(struct mlx5e_priv *priv)
+{
+	if (priv->fs.l2.trap_rule) {
+		mlx5_del_flow_rules(priv->fs.l2.trap_rule);
+		priv->fs.l2.trap_rule = NULL;
+	}
+}
+
 void mlx5e_enable_cvlan_filter(struct mlx5e_priv *priv)
 {
 	if (!priv->fs.vlan.cvlan_filter_disabled)
@@ -1444,11 +1470,13 @@ static int mlx5e_add_l2_flow_rule(struct mlx5e_priv *priv,
 	return err;
 }
 
-#define MLX5E_NUM_L2_GROUPS	   2
+#define MLX5E_NUM_L2_GROUPS	   3
 #define MLX5E_L2_GROUP1_SIZE	   BIT(15)
 #define MLX5E_L2_GROUP2_SIZE	   BIT(0)
+#define MLX5E_L2_GROUP_TRAP_SIZE   BIT(0) /* must be last */
 #define MLX5E_L2_TABLE_SIZE	   (MLX5E_L2_GROUP1_SIZE +\
-				    MLX5E_L2_GROUP2_SIZE)
+				    MLX5E_L2_GROUP2_SIZE +\
+				    MLX5E_L2_GROUP_TRAP_SIZE)
 static int mlx5e_create_l2_table_groups(struct mlx5e_l2_table *l2_table)
 {
 	int inlen = MLX5_ST_SZ_BYTES(create_flow_group_in);
@@ -1493,6 +1521,16 @@ static int mlx5e_create_l2_table_groups(struct mlx5e_l2_table *l2_table)
 		goto err_destroy_groups;
 	ft->num_groups++;
 
+	/* Flow Group for l2 traps */
+	memset(in, 0, inlen);
+	MLX5_SET_CFG(in, start_flow_index, ix);
+	ix += MLX5E_L2_GROUP_TRAP_SIZE;
+	MLX5_SET_CFG(in, end_flow_index, ix - 1);
+	ft->g[ft->num_groups] = mlx5_create_flow_group(ft->t, in);
+	if (IS_ERR(ft->g[ft->num_groups]))
+		goto err_destroy_groups;
+	ft->num_groups++;
+
 	kvfree(in);
 	return 0;