Re: [PATCH][v2] xfstest: add a test for the btrfs file extent gap issue

[Filipe Manana <fdmanana@gmail.com>]

On Tue, Feb 4, 2020 at 2:39 PM Josef Bacik <josef@toxicpanda.com> wrote:
>
> This is a test to validate that we're not adjusting up i_size before we
> have the appropriate file extents on disk.  We had a problem where
> i_size would be adjusted up without a contiguous range of file extents,
> which isn't ok without a special option enabled.
>
> Signed-off-by: Josef Bacik <josef@toxicpanda.com>

Reviewed-by: Filipe Manana <fdmanana@suse.com>

Thanks.

> ---
> v1->v2:
> - adjusted the commit interval time to make the test shorter
> - adjusted the write range so we didn't get tripped up by btrfs's delalloc
>   behavior
> - integrated all of Filipe's suggestions
>
>  tests/btrfs/172     | 76 +++++++++++++++++++++++++++++++++++++++++++++
>  tests/btrfs/172.out |  3 ++
>  tests/btrfs/group   |  1 +
>  3 files changed, 80 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 00000000..cae5f623
> --- /dev/null
> +++ b/tests/btrfs/172
> @@ -0,0 +1,76 @@
> +#! /bin/bash
> +# SPDX-License-Identifier: GPL-2.0
> +# Copyright (c) 2020 Facebook.  All Rights Reserved.
> +#
> +# FS QA Test 172
> +#
> +# Validate that without no-holes we do not get an i_size that is after a gap in
> +# the file extents on disk.  This is fixed by the following patches
> +#
> +#     btrfs: use the file extent tree infrastructure
> +#     btrfs: replace all uses of btrfs_ordered_update_i_size
> +#
> +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
> +. ./common/dmlogwrites
> +
> +# 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_log_writes
> +_require_xfs_io_command "sync_range"
> +
> +_log_writes_init $SCRATCH_DEV
> +_log_writes_mkfs "-O ^no-holes" >> $seqres.full 2>&1
> +
> +# There's not a straightforward way to commit the transaction without also
> +# flushing dirty pages, so shorten the commit interval to 1 so we're sure to get
> +# a commit with our broken file
> +_log_writes_mount -o commit=1
> +
> +$XFS_IO_PROG -f -c "pwrite 0 5m" $SCRATCH_MNT/file | _filter_xfs_io
> +$XFS_IO_PROG -f -c "sync_range -abw 4m 1m" $SCRATCH_MNT/file | _filter_xfs_io
> +
> +# Now wait for a transaction commit to happen, wait 2x just to be super sure
> +sleep 2
> +
> +_log_writes_unmount
> +_log_writes_remove
> +
> +cur=$(_log_writes_find_next_fua 0)
> +echo "cur=$cur" >> $seqres.full
> +while [ ! -z "$cur" ]; do
> +       _log_writes_replay_log_range $cur $SCRATCH_DEV >> $seqres.full
> +
> +       # We only care about the fs consistency, so just run fsck, we don't have
> +       # to mount the fs to validate it
> +       _check_scratch_fs
> +
> +       cur=$(_log_writes_find_next_fua $(($cur + 1)))
> +done
> +
> +# success, all done
> +status=0
> +exit
> diff --git a/tests/btrfs/172.out b/tests/btrfs/172.out
> new file mode 100644
> index 00000000..45051739
> --- /dev/null
> +++ b/tests/btrfs/172.out
> @@ -0,0 +1,3 @@
> +QA output created by 172
> +wrote 5242880/5242880 bytes at offset 0
> +XXX Bytes, X ops; XX:XX:XX.X (XXX YYY/sec and XXX ops/sec)
> diff --git a/tests/btrfs/group b/tests/btrfs/group
> index 4b64bf8b..53cb3451 100644
> --- a/tests/btrfs/group
> +++ b/tests/btrfs/group
> @@ -174,6 +174,7 @@
>  169 auto quick send
>  170 auto quick snapshot
>  171 auto quick qgroup
> +172 auto quick log replay
>  173 auto quick swap
>  174 auto quick swap
>  175 auto quick swap volume
> --
> 2.24.1
>


-- 
Filipe David Manana,

“Whether you think you can, or you think you can't — you're right.”