net/mlx5: Add API to set the namespace steering mode

Add API to set the flow steering root namesapce mode.
Setting new mode should be called before any steering operation
is executed on the namespace.
This API is going to be used by steering users such switchdev.
Signed-off-by: Maor Gottlieb <maorg@mellanox.com>
Reviewed-by: Mark Bloch <markb@mellanox.com>
Signed-off-by: Saeed Mahameed <saeedm@mellanox.com>

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

@@ -2995,5 +2995,54 @@ EXPORT_SYMBOL(mlx5_packet_reformat_dealloc);
 int mlx5_flow_namespace_set_peer(struct mlx5_flow_root_namespace *ns,
 				 struct mlx5_flow_root_namespace *peer_ns)
 {
+	if (peer_ns && ns->mode != peer_ns->mode) {
+		mlx5_core_err(ns->dev,
+			      "Can't peer namespace of different steering mode\n");
+		return -EINVAL;
+	}
+
 	return ns->cmds->set_peer(ns, peer_ns);
 }
+
+/* This function should be called only at init stage of the namespace.
+ * It is not safe to call this function while steering operations
+ * are executed in the namespace.
+ */
+int mlx5_flow_namespace_set_mode(struct mlx5_flow_namespace *ns,
+				 enum mlx5_flow_steering_mode mode)
+{
+	struct mlx5_flow_root_namespace *root;
+	const struct mlx5_flow_cmds *cmds;
+	int err;
+
+	root = find_root(&ns->node);
+	if (&root->ns != ns)
+	/* Can't set cmds to non root namespace */
+		return -EINVAL;
+
+	if (root->table_type != FS_FT_FDB)
+		return -EOPNOTSUPP;
+
+	if (root->mode == mode)
+		return 0;
+
+	if (mode == MLX5_FLOW_STEERING_MODE_SMFS)
+		cmds = mlx5_fs_cmd_get_dr_cmds();
+	else
+		cmds = mlx5_fs_cmd_get_fw_cmds();
+	if (!cmds)
+		return -EOPNOTSUPP;
+
+	err = cmds->create_ns(root);
+	if (err) {
+		mlx5_core_err(root->dev, "Failed to create flow namespace (%d)\n",
+			      err);
+		return err;
+	}
+
+	root->cmds->destroy_ns(root);
+	root->cmds = cmds;
+	root->mode = mode;
+
+	return 0;
+}

drivers/net/ethernet/mellanox/mlx5/core/fs_core.h

@@ -98,9 +98,15 @@ enum fs_fte_status {
 	FS_FTE_STATUS_EXISTING = 1UL << 0,
 };
 
+enum mlx5_flow_steering_mode {
+	MLX5_FLOW_STEERING_MODE_DMFS,
+	MLX5_FLOW_STEERING_MODE_SMFS
+};
+
 struct mlx5_flow_steering {
 	struct mlx5_core_dev *dev;
-	struct kmem_cache               *fgs_cache;
+	enum   mlx5_flow_steering_mode	mode;
+	struct kmem_cache		*fgs_cache;
 	struct kmem_cache               *ftes_cache;
 	struct mlx5_flow_root_namespace *root_ns;
 	struct mlx5_flow_root_namespace *fdb_root_ns;
@@ -235,6 +241,7 @@ struct mlx5_flow_group {
 
 struct mlx5_flow_root_namespace {
 	struct mlx5_flow_namespace	ns;
+	enum   mlx5_flow_steering_mode	mode;
 	struct mlx5_fs_dr_domain	fs_dr_domain;
 	enum   fs_flow_table_type	table_type;
 	struct mlx5_core_dev		*dev;
@@ -258,6 +265,9 @@ const struct mlx5_flow_cmds *mlx5_fs_cmd_get_fw_cmds(void);
 int mlx5_flow_namespace_set_peer(struct mlx5_flow_root_namespace *ns,
 				 struct mlx5_flow_root_namespace *peer_ns);
 
+int mlx5_flow_namespace_set_mode(struct mlx5_flow_namespace *ns,
+				 enum mlx5_flow_steering_mode mode);
+
 int mlx5_init_fs(struct mlx5_core_dev *dev);
 void mlx5_cleanup_fs(struct mlx5_core_dev *dev);