extent_from_logical
ret = extent_from_logical(fs_info, logical, path, &found_key, &flags);
int extent_from_logical(struct btrfs_fs_info *fs_info, u64 logical,
ret = extent_from_logical(fs_info, logical, &path, &found_key, &flags);
ret = extent_from_logical(fs_info, swarn.logical, path, &found_key,