[net-next 14/16] net/mlx5e: Add support for tc trap

[saeed@kernel.org]

From: Eli Cohen <eli@mellanox.com>

Support tc trap such that packets can explicitly be forwarded to slow
path if they match a specific rule.

In the example below, we want packets with src IP equals 7.7.7.8 to be
forwarded to software, in which case it will get to the appropriate
representor net device.

$ tc filter add dev eth1 protocol ip prio 1 root flower skip_sw \
    src_ip 7.7.7.8 action trap

Signed-off-by: Eli Cohen <eli@mellanox.com>
Reviewed-by: Roi Dayan <roid@nvidia.com>
Reviewed-by: Ariel Levkovich <lariel@nvidia.com>
Reviewed-by: Maor Dickman <maord@nvidia.com>
Signed-off-by: Saeed Mahameed <saeedm@nvidia.com>
---
 drivers/net/ethernet/mellanox/mlx5/core/en_tc.c | 10 ++++++++++
 1 file changed, 10 insertions(+)

diff --git a/drivers/net/ethernet/mellanox/mlx5/core/en_tc.c b/drivers/net/ethernet/mellanox/mlx5/core/en_tc.c
index fd53d101d8fd..2dded22a64a3 100644
--- a/drivers/net/ethernet/mellanox/mlx5/core/en_tc.c
+++ b/drivers/net/ethernet/mellanox/mlx5/core/en_tc.c
@@ -3943,6 +3943,16 @@ static int parse_tc_fdb_actions(struct mlx5e_priv *priv,
 			action |= MLX5_FLOW_CONTEXT_ACTION_DROP |
 				  MLX5_FLOW_CONTEXT_ACTION_COUNT;
 			break;
+		case FLOW_ACTION_TRAP:
+			if (!flow_offload_has_one_action(flow_action)) {
+				NL_SET_ERR_MSG_MOD(extack,
+						   "action trap is supported as a sole action only");
+				return -EOPNOTSUPP;
+			}
+			action |= (MLX5_FLOW_CONTEXT_ACTION_FWD_DEST |
+				   MLX5_FLOW_CONTEXT_ACTION_COUNT);
+			attr->flags |= MLX5_ESW_ATTR_FLAG_SLOW_PATH;
+			break;
 		case FLOW_ACTION_MPLS_PUSH:
 			if (!MLX5_CAP_ESW_FLOWTABLE_FDB(priv->mdev,
 							reformat_l2_to_l3_tunnel) ||
-- 
2.26.2