Re: [PATCH] generic/473: fix expectation properly in out file

[Su Yue <l@damenly.su>]

Cc to the author and linux-xfs, since it's xfsprogs related.

On Tue 23 Feb 2021 at 21:40, Chengguang Xu <cgxu519@mykernel.net> 
wrote:

> It seems the expected result of testcase of "Hole + Data"
> in generic/473 is not correct, so just fix it properly.
>

But it's not proper...

> Signed-off-by: Chengguang Xu <cgxu519@mykernel.net>
> ---
>  tests/generic/473.out | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/tests/generic/473.out b/tests/generic/473.out
> index 75816388..f1ee5805 100644
> --- a/tests/generic/473.out
> +++ b/tests/generic/473.out
> @@ -6,7 +6,7 @@ Data + Hole
>  1: [256..287]: hole
>  Hole + Data
>  0: [0..127]: hole
> -1: [128..255]: data
> +1: [128..135]: data
>
The line is produced by `$XFS_IO_PROG -c "fiemap -v 0 65k" $file | 
_filter_fiemap`.
0-64k is a hole and 64k-128k is a data extent.
fiemap ioctl always returns *complete* ranges of extents.

You may ask why the ending hole range is not aligned to 128 in 
473.out. Because
fiemap ioctl returns nothing of querying holes. xfs_io does the 
extra
print work for holes.

xfsprogs-dev/io/fiemap.c:
for holes:
 153     if (lstart > llast) {
 154         print_hole(0, 0, 0, cur_extent, lflag, true, llast, 
 lstart);
 155         cur_extent++;
 156         num_printed++;
 157     }

for the ending hole:
  381     if (cur_extent && last_logical < range_end)
  382         print_hole(foff_w, boff_w, tot_w, cur_extent, lflag, 
  !vflag,
  383                BTOBBT(last_logical), BTOBBT(range_end));

>  Hole + Data + Hole
>  0: [0..127]: hole
>  1: [128..255]: data