Re: [PATCH v2 2/4] punch: Implement fixup for fiemap range queries

Eryu Guan
2017-11-07T05:18:57Z

On Tue, Oct 31, 2017 at 04:11:34PM +0200, Nikolay Borisov wrote:
> With the new range query support for the fiemap command,
> the command also started printing hole extent for files which
> consist of only a hole. This change breaks tests which are
> executed with a version of xfs_io that doesn't support fiemap's
> range query.
>
> Fix this by implementing a function which will fixup the output
> of tests which are broken by emulating the output on older
> xfs_io versions
>
> Signed-off-by: Nikolay Borisov <nborisov@suse.com>
> ---
> common/punch | 19 +++++++++++++++++++
> 1 file changed, 19 insertions(+)
>
> diff --git a/common/punch b/common/punch
> index c4ed261..b20dc30 100644
> --- a/common/punch
> +++ b/common/punch
> @@ -218,6 +218,23 @@ _filter_fiemap()
> _coalesce_extents
> }
>
> +_fiemap_range_fixup()

Good to have some comments too on what this function does.

> +{
> + #check if we support ranged query
> + $XFS_IO_PROG -c "help fiemap" | head -n 1 | grep -q "[offset [len]]"

return immediately if fiemap supports range query?

Thanks,
Eryu

> + local range_sup=$?
> + #check if the file consists of a single hole only
> + echo "$1" | grep -q "^0\: \[.*\]\: hole$"
> + local sole_hole=$?
> + local filesize="$(((`stat -c %s $1` / 512) - 1))"
> + local output_line_num=`$XFS_IO_PROG -c 'fiemap' $testfile | wc -l`
> +
> + if [ $range_sup -eq 1 ] && [ $sole_hole -eq 1 ] && [ $output_line_num -eq 1 ]
> + then
> + echo "0: [0..$filesize]: hole"
> + fi
> +}
> +
> _filter_fiemap_flags()
> {
> $AWK_PROG '
> @@ -363,6 +380,7 @@ _test_generic_punch()
> $XFS_IO_PROG -f -c "truncate $_20k" \
> -c "$zero_cmd $_4k $_8k" \
> -c "$map_cmd -v" $testfile | $filter_cmd
> + _fiemap_range_fixup $testfile
> [ $? -ne 0 ] && die_now
> _md5_checksum $testfile
>
> @@ -470,6 +488,7 @@ _test_generic_punch()
> -c "pwrite $_8k $_4k" $sync_cmd \
> -c "$zero_cmd $_4k $_12k" \
> -c "$map_cmd -v" $testfile | $filter_cmd
> + _fiemap_range_fixup $testfile
> [ $? -ne 0 ] && die_now
> _md5_checksum $testfile
>
> --
> 2.7.4
>