RDMA/mlx5: Add new flow action verb - packet reformat

For now, only add L2_TUNNEL_TO_L2 option. This will allow to perform
generic decap operation if the encapsulating protocol is L2 based, and the
inner packet is also L2 based. For example this can be used to decap VXLAN
packets.

Signed-off-by: Mark Bloch <markb@mellanox.com>
Signed-off-by: Leon Romanovsky <leonro@mellanox.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>

drivers/infiniband/hw/mlx5/flow.c

@@ -202,6 +202,8 @@ void mlx5_ib_destroy_flow_action_raw(struct mlx5_ib_flow_action *maction)
 		mlx5_modify_header_dealloc(maction->flow_action_raw.dev->mdev,
 					   maction->flow_action_raw.action_id);
 		break;
+	case MLX5_IB_FLOW_ACTION_DECAP:
+		break;
 	default:
 		break;
 	}
@@ -286,6 +288,64 @@ static int UVERBS_HANDLER(MLX5_IB_METHOD_FLOW_ACTION_CREATE_MODIFY_HEADER)(
 	return 0;
 }
 
+static bool mlx5_ib_flow_action_packet_reformat_valid(struct mlx5_ib_dev *ibdev,
+						      u8 packet_reformat_type,
+						      u8 ft_type)
+{
+	switch (packet_reformat_type) {
+	case MLX5_IB_UAPI_FLOW_ACTION_PACKET_REFORMAT_TYPE_L2_TUNNEL_TO_L2:
+		if (ft_type == MLX5_IB_UAPI_FLOW_TABLE_TYPE_NIC_RX)
+			return MLX5_CAP_FLOWTABLE_NIC_RX(ibdev->mdev, decap);
+		break;
+	default:
+		break;
+	}
+
+	return false;
+}
+
+static int UVERBS_HANDLER(MLX5_IB_METHOD_FLOW_ACTION_CREATE_PACKET_REFORMAT)(
+	struct ib_uverbs_file *file,
+	struct uverbs_attr_bundle *attrs)
+{
+	struct ib_uobject *uobj = uverbs_attr_get_uobject(attrs,
+		MLX5_IB_ATTR_CREATE_PACKET_REFORMAT_HANDLE);
+	struct mlx5_ib_dev *mdev = to_mdev(uobj->context->device);
+	enum mlx5_ib_uapi_flow_action_packet_reformat_type dv_prt;
+	enum mlx5_ib_uapi_flow_table_type ft_type;
+	struct mlx5_ib_flow_action *maction;
+	int ret;
+
+	ret = uverbs_get_const(&ft_type, attrs,
+			       MLX5_IB_ATTR_CREATE_PACKET_REFORMAT_FT_TYPE);
+	if (ret)
+		return ret;
+
+	ret = uverbs_get_const(&dv_prt, attrs,
+			       MLX5_IB_ATTR_CREATE_PACKET_REFORMAT_TYPE);
+	if (ret)
+		return ret;
+
+	if (!mlx5_ib_flow_action_packet_reformat_valid(mdev, dv_prt, ft_type))
+		return -EOPNOTSUPP;
+
+	maction = kzalloc(sizeof(*maction), GFP_KERNEL);
+	if (!maction)
+		return -ENOMEM;
+
+	if (dv_prt ==
+	    MLX5_IB_UAPI_FLOW_ACTION_PACKET_REFORMAT_TYPE_L2_TUNNEL_TO_L2) {
+		maction->flow_action_raw.sub_type =
+			MLX5_IB_FLOW_ACTION_DECAP;
+		maction->flow_action_raw.dev = mdev;
+	}
+
+	uverbs_flow_action_fill_action(&maction->ib_action, uobj,
+				       uobj->context->device,
+				       IB_FLOW_ACTION_UNSPECIFIED);
+	return 0;
+}
+
 DECLARE_UVERBS_NAMED_METHOD(
 	MLX5_IB_METHOD_CREATE_FLOW,
 	UVERBS_ATTR_IDR(MLX5_IB_ATTR_CREATE_FLOW_HANDLE,
@@ -335,10 +395,24 @@ DECLARE_UVERBS_NAMED_METHOD(
 			     enum mlx5_ib_uapi_flow_table_type,
 			     UA_MANDATORY));
 
+DECLARE_UVERBS_NAMED_METHOD(
+	MLX5_IB_METHOD_FLOW_ACTION_CREATE_PACKET_REFORMAT,
+	UVERBS_ATTR_IDR(MLX5_IB_ATTR_CREATE_PACKET_REFORMAT_HANDLE,
+			UVERBS_OBJECT_FLOW_ACTION,
+			UVERBS_ACCESS_NEW,
+			UA_MANDATORY),
+	UVERBS_ATTR_CONST_IN(MLX5_IB_ATTR_CREATE_PACKET_REFORMAT_TYPE,
+			     enum mlx5_ib_uapi_flow_action_packet_reformat_type,
+			     UA_MANDATORY),
+	UVERBS_ATTR_CONST_IN(MLX5_IB_ATTR_CREATE_PACKET_REFORMAT_FT_TYPE,
+			     enum mlx5_ib_uapi_flow_table_type,
+			     UA_MANDATORY));
+
 ADD_UVERBS_METHODS(
 	mlx5_ib_flow_actions,
 	UVERBS_OBJECT_FLOW_ACTION,
-	&UVERBS_METHOD(MLX5_IB_METHOD_FLOW_ACTION_CREATE_MODIFY_HEADER));
+	&UVERBS_METHOD(MLX5_IB_METHOD_FLOW_ACTION_CREATE_MODIFY_HEADER),
+	&UVERBS_METHOD(MLX5_IB_METHOD_FLOW_ACTION_CREATE_PACKET_REFORMAT));
 
 DECLARE_UVERBS_NAMED_METHOD(
 	MLX5_IB_METHOD_FLOW_MATCHER_CREATE,

drivers/infiniband/hw/mlx5/mlx5_ib.h

@@ -153,6 +153,7 @@ struct mlx5_ib_pd {
 
 enum {
 	MLX5_IB_FLOW_ACTION_MODIFY_HEADER,
+	MLX5_IB_FLOW_ACTION_DECAP,
 };
 
 #define MLX5_IB_FLOW_MCAST_PRIO		(MLX5_BY_PASS_NUM_PRIOS - 1)

include/uapi/rdma/mlx5_user_ioctl_cmds.h

@@ -168,6 +168,7 @@ enum mlx5_ib_flow_methods {
 
 enum mlx5_ib_flow_action_methods {
 	MLX5_IB_METHOD_FLOW_ACTION_CREATE_MODIFY_HEADER = (1U << UVERBS_ID_NS_SHIFT),
+	MLX5_IB_METHOD_FLOW_ACTION_CREATE_PACKET_REFORMAT,
 };
 
 enum mlx5_ib_create_flow_action_create_modify_header_attrs {
@@ -176,4 +177,10 @@ enum mlx5_ib_create_flow_action_create_modify_header_attrs {
 	MLX5_IB_ATTR_CREATE_MODIFY_HEADER_FT_TYPE,
 };
 
+enum mlx5_ib_create_flow_action_create_packet_reformat_attrs {
+	MLX5_IB_ATTR_CREATE_PACKET_REFORMAT_HANDLE = (1U << UVERBS_ID_NS_SHIFT),
+	MLX5_IB_ATTR_CREATE_PACKET_REFORMAT_TYPE,
+	MLX5_IB_ATTR_CREATE_PACKET_REFORMAT_FT_TYPE,
+};
+
 #endif

include/uapi/rdma/mlx5_user_ioctl_verbs.h

@@ -44,5 +44,9 @@ enum mlx5_ib_uapi_flow_table_type {
 	MLX5_IB_UAPI_FLOW_TABLE_TYPE_NIC_TX	= 0x1,
 };
 
+enum mlx5_ib_uapi_flow_action_packet_reformat_type {
+	MLX5_IB_UAPI_FLOW_ACTION_PACKET_REFORMAT_TYPE_L2_TUNNEL_TO_L2 = 0x0,
+};
+
 #endif