btrfs_get_or_create_delayed_node
delayed_node = btrfs_get_or_create_delayed_node(dir, &delayed_node_tracker);
node = btrfs_get_or_create_delayed_node(dir, &delayed_node_tracker);
delayed_node = btrfs_get_or_create_delayed_node(inode, &delayed_node_tracker);
delayed_node = btrfs_get_or_create_delayed_node(inode, &delayed_node_tracker);