Re: [PATCH v3] test unaligned punch hole at ENOSPC

[Anand Jain <anand.jain@oracle.com>]

On 09/29/2018 01:08 AM, Filipe Manana wrote:
> On Fri, Sep 28, 2018 at 3:51 PM Anand Jain <anand.jain@oracle.com> wrote:
>>
>> Try to punch hole with unaligned size and offset when the FS
>> returns ENOSPC
> 
> The FS returns ENOSPC is confusing. It's more clear to say when the
> filesystem doesn't have more space available for data allocation.
>>
>> Signed-off-by: Anand Jain <anand.jain@oracle.com>
>> ---
>> v2->v3:
>>   add _require_xfs_io_command "fpunch"
>>   add more logs to $seqfull.full
>>     mount options and
>>     group profile info
>>   add sync after dd upto ENOSPC
>>   drop fallocate -p and use xfs_io punch to create holes
>> v1->v2: Use at least 256MB to test.
>> This test case fails on btrfs as of now.
>>
>>   tests/btrfs/172     | 74 +++++++++++++++++++++++++++++++++++++++++++++++++++++
>>   tests/btrfs/172.out |  2 ++
>>   tests/btrfs/group   |  1 +
>>   3 files changed, 77 insertions(+)
>>   create mode 100755 tests/btrfs/172
>>   create mode 100644 tests/btrfs/172.out
>>
>> diff --git a/tests/btrfs/172 b/tests/btrfs/172
>> new file mode 100755
>> index 000000000000..59413a5de12f
>> --- /dev/null
>> +++ b/tests/btrfs/172
>> @@ -0,0 +1,74 @@
>> +#! /bin/bash
>> +# SPDX-License-Identifier: GPL-2.0
>> +# Copyright (c) 2018 Oracle. All Rights Reserved.
>> +#
>> +# FS QA Test 172
>> +#
>> +# Test if the unaligned (by size and offset) punch hole is successful when FS
>> +# is at ENOSPC.
>> +#
>> +seq=`basename $0`
>> +seqres=$RESULT_DIR/$seq
>> +echo "QA output created by $seq"
>> +
>> +here=`pwd`
>> +tmp=/tmp/$$
>> +status=1       # failure is the default!
>> +trap "_cleanup; exit \$status" 0 1 2 3 15
>> +
>> +_cleanup()
>> +{
>> +       cd /
>> +       rm -f $tmp.*
>> +}
>> +
>> +# get standard environment, filters and checks
>> +. ./common/rc
>> +. ./common/filter
>> +
>> +# remove previous $seqres.full before test
>> +rm -f $seqres.full
>> +
>> +# real QA test starts here
>> +
>> +# Modify as appropriate.
>> +_supported_fs btrfs
>> +_supported_os Linux
>> +_require_scratch
>> +_require_xfs_io_command "fpunch"
>> +
>> +_scratch_mkfs_sized $((256 * 1024 *1024)) >> $seqres.full
>> +
>> +# max_inline helps to create regular extent
> max_inline ensures data is not inlined within metadata extents

  Right. Hmm I saw the term regular extent used some where,
  so used it here. Looks that wasn't better?

>> +_scratch_mount "-o max_inline=0,nodatacow"
>> +
>> +cat /proc/self/mounts | grep $SCRATCH_DEV >> $seqres.full
>> +$BTRFS_UTIL_PROG filesystem df $SCRATCH_MNT >> $seqres.full
>> +
>> +extent_size=$(_scratch_btrfs_sectorsize)
>> +unalign_by=512
>> +echo extent_size=$extent_size unalign_by=$unalign_by >> $seqres.full
>> +
>> +$XFS_IO_PROG -f -d -c "pwrite -S 0xab 0 $((extent_size * 10))" \
>> +                                       $SCRATCH_MNT/testfile >> $seqres.full
>> +
>> +echo "Fill fs upto ENOSPC" >> $seqres.full
> Fill all space available for data and all unallocated space.

  Will update comment. (I hope that's what you mean?)

>> +dd status=none if=/dev/zero of=$SCRATCH_MNT/filler bs=512 >> $seqres.full 2>&1
> Why do you use dd here and not xfs_io?

  What I figured out xfs_io can't write until FS is full, as you need to
  specify the size for pwrite. OR did I miss something? I see some test
  cases just specify some arbitrary large number big enough than the FS.
  I didn't like that approach.

>> +sync
> Why is the sync needed?

  Yep not needed. Will remove in v6.

>> +
>> +hole_offset=0
>> +hole_len=$unalign_by
>> +$XFS_IO_PROG -f -d -c "fpunch $hole_offset $hole_len" $SCRATCH_MNT/testfile
> 
> No need to pass -f anymore. No need for -d either.

  Ah. Thanks will fix in v6.

>> +
>> +hole_offset=$(($extent_size + $unalign_by))
>> +hole_len=$(($extent_size - $unalign_by))
>> +$XFS_IO_PROG -f -d -c "fpunch $hole_offset $hole_len" $SCRATCH_MNT/testfile
> 
> No need to pass -f anymore. No need for -d either.

  Will fix in v6.

>> +
>> +hole_offset=$(($extent_size * 2 + $unalign_by))
>> +hole_len=$(($extent_size * 5))
>> +$XFS_IO_PROG -f -d -c "fpunch $hole_offset $hole_len" $SCRATCH_MNT/testfile
> 
> No need to pass -f anymore. No need for -d either.

  Got it.

Thanks, Anand

>> +
>> +# success, all done
>> +echo "Silence is golden"
>> +status=0
>> +exit
>> diff --git a/tests/btrfs/172.out b/tests/btrfs/172.out
>> new file mode 100644
>> index 000000000000..ce2de3f0d107
>> --- /dev/null
>> +++ b/tests/btrfs/172.out
>> @@ -0,0 +1,2 @@
>> +QA output created by 172
>> +Silence is golden
>> diff --git a/tests/btrfs/group b/tests/btrfs/group
>> index feffc45b6564..7e1a638ab7e1 100644
>> --- a/tests/btrfs/group
>> +++ b/tests/btrfs/group
>> @@ -174,3 +174,4 @@
>>   169 auto quick send
>>   170 auto quick snapshot
>>   171 auto quick qgroup
>> +172 auto quick
>> --
>> 1.8.3.1
>>
> 
>