Re: [PATCH v3 4/4] xfstests: btrfs/134: add test for incremental send which renames a directory already being deleted

From: robbieko <robbieko@synology.com>
To: fdmanana@gmail.com
Cc: fstests@vger.kernel.org, linux-btrfs@vger.kernel.org
Subject: Re: [PATCH v3 4/4] xfstests: btrfs/134: add test for incremental send which renames a directory already being deleted
Date: Thu, 05 Jan 2017 13:22:41 +0800	[thread overview]
Message-ID: <edb59fe19caeed584141d9616f428c10@synology.com> (raw)
In-Reply-To: <CAL3q7H6eNoP6v+T=AXwB+5V0z_GMaJq8BxU=PO6z0mhRNtyuBA@mail.gmail.com>

Filipe Manana 於 2017-01-04 21:07 寫到:
> On Wed, Jan 4, 2017 at 10:53 AM, robbieko <robbieko@synology.com> 
> wrote:
>> From: Robbie Ko <robbieko@synology.com>
>> 
>> Test that an incremental send operation dosen't work because
> 
> dosen't -> doesn't
> 
>> it tries to rename a directory which is already deleted.
>> 
>> This test exercises scenarios used to fail in btrfs and are fixed by
>> the following patch for the linux kernel:
>> 
>> "Btrfs: incremental send, add generation check for inode is waiting 
>> for move."
>> 
>> Signed-off-by: Robbie Ko <robbieko@synology.com>
>> ---
>> V3: remove "run_" based helpers
>> V2: improve the change log
>> 
>>  tests/btrfs/134     | 124 
>> ++++++++++++++++++++++++++++++++++++++++++++++++++++
>>  tests/btrfs/134.out |   9 ++++
>>  tests/btrfs/group   |   1 +
>>  3 files changed, 134 insertions(+)
>>  create mode 100755 tests/btrfs/134
>>  create mode 100644 tests/btrfs/134.out
>> 
>> diff --git a/tests/btrfs/134 b/tests/btrfs/134
>> new file mode 100755
>> index 0000000..87c108e
>> --- /dev/null
>> +++ b/tests/btrfs/134
>> @@ -0,0 +1,124 @@
>> +#! /bin/bash
>> +# FS QA Test No. btrfs/134
>> +#
>> +# Test that an incremental send operation dosen't work because
> 
> dosen't -> doesn't
> 
>> +# it tries to rename a directory which is already deleted.
>> +#
>> +#-----------------------------------------------------------------------
>> +# Copyright (C) 2016 Synology Inc. All Rights Reserved.
> 
> We're already in 2017 btw.
> 
>> +# Author: Robbie Ko <robbieko@synology.com>
>> +#
>> +# This program is free software; you can redistribute it and/or
>> +# modify it under the terms of the GNU General Public License as
>> +# published by the Free Software Foundation.
>> +#
>> +# This program is distributed in the hope that it would be useful,
>> +# but WITHOUT ANY WARRANTY; without even the implied warranty of
>> +# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
>> +# GNU General Public License for more details.
>> +#
>> +# You should have received a copy of the GNU General Public License
>> +# along with this program; if not, write the Free Software 
>> Foundation,
>> +# Inc.,  51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
>> +#-----------------------------------------------------------------------
>> +#
>> +
>> +seq=`basename $0`
>> +seqres=$RESULT_DIR/$seq
>> +echo "QA output created by $seq"
>> +
>> +tmp=/tmp/$$
>> +status=1       # failure is the default!
>> +trap "_cleanup; exit \$status" 0 1 2 3 15
>> +
>> +_cleanup()
>> +{
>> +       cd /
>> +       rm -fr $send_files_dir
>> +       rm -f $tmp.*
>> +}
>> +
>> +# get standard environment, filters and checks
>> +. ./common/rc
>> +. ./common/filter
>> +
>> +# real QA test starts here
>> +_supported_fs btrfs
>> +_supported_os Linux
>> +_require_test
>> +_require_scratch
>> +_require_fssum
>> +
>> +send_files_dir=$TEST_DIR/btrfs-test-$seq
>> +
>> +rm -f $seqres.full
>> +rm -fr $send_files_dir
>> +mkdir $send_files_dir
>> +
>> +_scratch_mkfs >>$seqres.full 2>&1
>> +_scratch_mount
>> +
>> +mkdir $SCRATCH_MNT/d1
>> +mkdir $SCRATCH_MNT/d4
>> +mkdir $SCRATCH_MNT/d3
>> +
>> +# Filesystem looks like:
>> +#
>> +# .                                                             (ino 
>> 256)
>> +# |--- d1                                                       (ino 
>> 257)
>> +# |--- d4                                                       (ino 
>> 258)
>> +# |--- d3                                                       (ino 
>> 259)
>> +#
>> +$BTRFS_UTIL_PROG subvolume snapshot -r $SCRATCH_MNT \
>> +    $SCRATCH_MNT/mysnap1 > /dev/null
>> +
>> +$BTRFS_UTIL_PROG send $SCRATCH_MNT/mysnap1 -f \
>> +    $send_files_dir/1.snap 2>&1 1>/dev/null | _filter_scratch
>> +
>> +_scratch_unmount
>> +_scratch_mkfs >>$seqres.full 2>&1
>> +_scratch_mount
> 
> I don't understand this. Why do we need to recreate the filesystem?
> Why don't we just create the first and second snapshots in the same
> filesystems, just like all the other tests do.
> 
> I would like to see comments explaining why that is needed and how/why
> the incremental send used to fail (in a user understandable way, not
> in a very technical way referring to pieces of code of btrfs), just
> like most of the existing send/receive tests have.
> 
> I haven't tried nor reviewed the btrfs patches, but I hope to do it 
> this week.
> 
> thanks

Does not require recreate the filesystem, it just a scenario,
there are many ways to do the same thing,
we just need to use the same inode number, but different from the old 
one.
Let btrfs send need to recreate dir.

The primary mistake is "ERROR: rename d1 -> o257-44-0 failed: No such 
file or directory"
But in fact the old d1 has been deleted.

thanks.

>> +mkdir $SCRATCH_MNT/d1
>> +mkdir $SCRATCH_MNT/d2
>> +mkdir $SCRATCH_MNT/d3
>> +mkdir $SCRATCH_MNT/d4
>> +mv $SCRATCH_MNT/d1 $SCRATCH_MNT/d3/d1
>> +mv $SCRATCH_MNT/d3 $SCRATCH_MNT/d4/d3
>> +mv $SCRATCH_MNT/d2 $SCRATCH_MNT/d1
>> +
>> +# Filesystem now looks like:
>> +#
>> +# .                                                             (ino 
>> 256)
>> +# |--- d1                                                       (ino 
>> 258)
>> +# |--- d4                                                       (ino 
>> 260)
>> +# |    |--- d3/                                                 (ino 
>> 259)
>> +# |    |    |--- d1/                                            (ino 
>> 257)
>> +#
>> +$BTRFS_UTIL_PROG subvolume snapshot -r $SCRATCH_MNT \
>> +    $SCRATCH_MNT/mysnap2 > /dev/null
>> +
>> +$BTRFS_UTIL_PROG receive $SCRATCH_MNT -f $send_files_dir/1.snap > 
>> /dev/null
>> +rm $send_files_dir/1.snap
>> +
>> +$FSSUM_PROG -A -f -w $send_files_dir/1.fssum $SCRATCH_MNT/mysnap1
>> +$FSSUM_PROG -A -f -w $send_files_dir/2.fssum $SCRATCH_MNT/mysnap2
>> +
>> +$BTRFS_UTIL_PROG send $SCRATCH_MNT/mysnap1 -f \
>> +    $send_files_dir/1.snap 2>&1 1>/dev/null | _filter_scratch
>> +$BTRFS_UTIL_PROG send -p $SCRATCH_MNT/mysnap1 $SCRATCH_MNT/mysnap2 \
>> +       -f $send_files_dir/2.snap 2>&1 1>/dev/null | _filter_scratch
>> +
>> +# Now recreate the filesystem by receiving both send streams and 
>> verify we get
>> +# the same content that the original filesystem had.
>> +_scratch_unmount
>> +_scratch_mkfs >>$seqres.full 2>&1
>> +_scratch_mount
>> +
>> +$BTRFS_UTIL_PROG receive $SCRATCH_MNT -f $send_files_dir/1.snap > 
>> /dev/null
>> +$FSSUM_PROG -r $send_files_dir/1.fssum $SCRATCH_MNT/mysnap1
>> +$BTRFS_UTIL_PROG receive $SCRATCH_MNT -f $send_files_dir/2.snap > 
>> /dev/null
>> +$FSSUM_PROG -r $send_files_dir/2.fssum $SCRATCH_MNT/mysnap2
>> +
>> +echo "Silence is golden"
>> +status=0
>> +exit
>> diff --git a/tests/btrfs/134.out b/tests/btrfs/134.out
>> new file mode 100644
>> index 0000000..700a78f
>> --- /dev/null
>> +++ b/tests/btrfs/134.out
>> @@ -0,0 +1,9 @@
>> +QA output created by 134
>> +At subvol SCRATCH_MNT/mysnap1
>> +At subvol mysnap1
>> +At subvol SCRATCH_MNT/mysnap1
>> +At subvol SCRATCH_MNT/mysnap2
>> +At subvol mysnap1
>> +OK
>> +OK
>> +Silence is golden
>> diff --git a/tests/btrfs/group b/tests/btrfs/group
>> index 779caec..831283e 100644
>> --- a/tests/btrfs/group
>> +++ b/tests/btrfs/group
>> @@ -136,3 +136,4 @@
>>  131 auto quick send
>>  132 auto quick send
>>  133 auto quick send
>> +134 auto quick send
>> --
>> 1.9.1
>> 
>> --
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