xfs_rtfind_forw
error = xfs_rtfind_forw(&args, start, end, &rtend);
error = xfs_rtfind_forw(args, end, args->rtg->rtg_extents - 1,
int xfs_rtfind_forw(struct xfs_rtalloc_args *args, xfs_rtxnum_t start,
error = xfs_rtfind_forw(args, end, args->rtg->rtg_extents - 1,
error = xfs_rtfind_forw(args, next, end, &i);