RDMA/mlx5: RDMA_RX flow type support for user applications

Currently user applications can only steer TCP/IP(NIC RX/RX) traffic.
This patch adds RDMA_RX as a new flow type to allow the user to insert
steering rules to control RDMA traffic.
Two destinations are supported(but not set at the same time): devx
flow table object and QP.
Signed-off-by: Mark Zhang <markz@mellanox.com>
Signed-off-by: Leon Romanovsky <leonro@mellanox.com>
Link: https://lore.kernel.org/r/20190819113626.20284-4-leon@kernel.orgSigned-off-by: Doug Ledford <dledford@redhat.com>

drivers/infiniband/hw/mlx5/flow.c

@@ -32,6 +32,9 @@ mlx5_ib_ft_type_to_namespace(enum mlx5_ib_uapi_flow_table_type table_type,
 	case MLX5_IB_UAPI_FLOW_TABLE_TYPE_FDB:
 		*namespace = MLX5_FLOW_NAMESPACE_FDB;
 		break;
+	case MLX5_IB_UAPI_FLOW_TABLE_TYPE_RDMA_RX:
+		*namespace = MLX5_FLOW_NAMESPACE_RDMA_RX;
+		break;
 	default:
 		return -EINVAL;
 	}
@@ -101,6 +104,11 @@ static int UVERBS_HANDLER(MLX5_IB_METHOD_CREATE_FLOW)(
 	if (fs_matcher->ns_type == MLX5_FLOW_NAMESPACE_FDB && !dest_devx)
 		return -EINVAL;
 
+	/* Allow only DEVX object or QP as dest when inserting to RDMA_RX */
+	if ((fs_matcher->ns_type == MLX5_FLOW_NAMESPACE_RDMA_RX) &&
+	    ((!dest_devx && !dest_qp) || (dest_devx && dest_qp)))
+		return -EINVAL;
+
 	if (dest_devx) {
 		devx_obj = uverbs_attr_get_obj(
 			attrs, MLX5_IB_ATTR_CREATE_FLOW_DEST_DEVX);
@@ -112,8 +120,9 @@ static int UVERBS_HANDLER(MLX5_IB_METHOD_CREATE_FLOW)(
 		 */
 		if (!mlx5_ib_devx_is_flow_dest(devx_obj, &dest_id, &dest_type))
 			return -EINVAL;
-		/* Allow only flow table as dest when inserting to FDB */
-		if (fs_matcher->ns_type == MLX5_FLOW_NAMESPACE_FDB &&
+		/* Allow only flow table as dest when inserting to FDB or RDMA_RX */
+		if ((fs_matcher->ns_type == MLX5_FLOW_NAMESPACE_FDB ||
+		     fs_matcher->ns_type == MLX5_FLOW_NAMESPACE_RDMA_RX) &&
 		    dest_type != MLX5_FLOW_DESTINATION_TYPE_FLOW_TABLE)
 			return -EINVAL;
 	} else if (dest_qp) {

drivers/infiniband/hw/mlx5/main.c

@@ -3963,6 +3963,11 @@ _get_flow_table(struct mlx5_ib_dev *dev,
 		    esw_encap)
 			flags |= MLX5_FLOW_TABLE_TUNNEL_EN_REFORMAT;
 		priority = FDB_BYPASS_PATH;
+	} else if (fs_matcher->ns_type == MLX5_FLOW_NAMESPACE_RDMA_RX) {
+		max_table_size =
+			BIT(MLX5_CAP_FLOWTABLE_RDMA_RX(dev->mdev,
+						       log_max_ft_size));
+		priority = fs_matcher->priority;
 	}
 
 	max_table_size = min_t(int, max_table_size, MLX5_FS_MAX_ENTRIES);
@@ -3977,6 +3982,8 @@ _get_flow_table(struct mlx5_ib_dev *dev,
 		prio = &dev->flow_db->egress_prios[priority];
 	else if (fs_matcher->ns_type == MLX5_FLOW_NAMESPACE_FDB)
 		prio = &dev->flow_db->fdb;
+	else if (fs_matcher->ns_type == MLX5_FLOW_NAMESPACE_RDMA_RX)
+		prio = &dev->flow_db->rdma_rx[priority];
 
 	if (!prio)
 		return ERR_PTR(-EINVAL);

drivers/infiniband/hw/mlx5/mlx5_ib.h

@@ -200,6 +200,7 @@ struct mlx5_ib_flow_db {
 	struct mlx5_ib_flow_prio	sniffer[MLX5_IB_NUM_SNIFFER_FTS];
 	struct mlx5_ib_flow_prio	egress[MLX5_IB_NUM_EGRESS_FTS];
 	struct mlx5_ib_flow_prio	fdb;
+	struct mlx5_ib_flow_prio	rdma_rx[MLX5_IB_NUM_FLOW_FT];
 	struct mlx5_flow_table		*lag_demux_ft;
 	/* Protect flow steering bypass flow tables
 	 * when add/del flow rules.

include/uapi/rdma/mlx5_user_ioctl_verbs.h

@@ -43,6 +43,7 @@ enum mlx5_ib_uapi_flow_table_type {
 	MLX5_IB_UAPI_FLOW_TABLE_TYPE_NIC_RX     = 0x0,
 	MLX5_IB_UAPI_FLOW_TABLE_TYPE_NIC_TX	= 0x1,
 	MLX5_IB_UAPI_FLOW_TABLE_TYPE_FDB	= 0x2,
+	MLX5_IB_UAPI_FLOW_TABLE_TYPE_RDMA_RX	= 0x3,
 };
 
 enum mlx5_ib_uapi_flow_action_packet_reformat_type {