--- fs/btrfs/ioctl.c

+++ fs/btrfs/ioctl.c

@@ -285,6 +285,10 @@ static noinline int create_subvol(struct

inode_item->nbytes = cpu_to_le64(root->leafsize);

inode_item->mode = cpu_to_le32(S_IFDIR | 0755);

+ root_item.flags = 0;

+ root_item.byte_limit = 0;

+ inode_item->flags = cpu_to_le64(BTRFS_INODE_ROOT_ITEM_INIT);

+

btrfs_set_root_bytenr(&root_item, leaf->start);

btrfs_set_root_generation(&root_item, trans->transid);

btrfs_set_root_level(&root_item, 0);