btrfs_block_group_root
root = btrfs_block_group_root(fs_info);
struct btrfs_root *root = btrfs_block_group_root(fs_info);
struct btrfs_root *root = btrfs_block_group_root(fs_info);
struct btrfs_root *root = btrfs_block_group_root(info);
struct btrfs_root *root = btrfs_block_group_root(fs_info);
struct btrfs_root *root = btrfs_block_group_root(fs_info);
struct btrfs_root *root = btrfs_block_group_root(fs_info);