> + if (lseek(file_fd->fd, outmap[extent].bmv_length, SEEK_CUR) < 0) {
> fsrprintf(_("could not lseek in file: %s : %s\n"),
Maybe avoid the overly long lines here?
> -int read_fd_bmap(int fd, struct xfs_bstat *sin, int *cur_nextents)
> +int read_fd_bmap(int fd, struct xfs_bulkstat *sin, int *cur_nextents)
Maybe fix the weird formatting here while you're at it?
Otherwise looks good:
Reviewed-by: Christoph Hellwig <hch@xxxxxx>
