Re: [f2fs-dev] [PATCH] f2fs/008: test snapshot creation/deletion on lvm device

[Zorro L. <zl...@re...>]

On Mon, Dec 02, 2024 at 07:43:07PM +0800, Chao Yu wrote:
> This patch introduce a regression testcase to check whether
> f2fs can handle discard correctly once underlying lvm device
> changes to not support discard after user creates snapshot
> on it.
> 
> Related bug was fixed by commit bc8aeb04fd80 ("f2fs: fix to
> drop all discards after creating snapshot on lvm device")
> 
> Cc: Jaegeuk Kim <ja...@ke...>
> Signed-off-by: Chao Yu <ch...@ke...>
> ---
>  tests/f2fs/008     | 53 ++++++++++++++++++++++++++++++++++++++++++++++
>  tests/f2fs/008.out |  2 ++
>  2 files changed, 55 insertions(+)
>  create mode 100755 tests/f2fs/008
>  create mode 100644 tests/f2fs/008.out
> 
> diff --git a/tests/f2fs/008 b/tests/f2fs/008
> new file mode 100755
> index 00000000..a9a3f263
> --- /dev/null
> +++ b/tests/f2fs/008
> @@ -0,0 +1,53 @@
> +#! /bin/bash
> +# SPDX-License-Identifier: GPL-2.0
> +# Copyright (c) 2024 Oppo.  All Rights Reserved.
> +#
> +# FS QA Test No. f2fs/008
> +#
> +# This is a regression test to check whether f2fs can handle
> +# discard correctly once underlying lvm device changes to not
> +# support discard after user creates snapshot on it.
> +#
> +
> +. ./common/preamble
> +_begin_fstest auto quick rw
> +
> +_fixed_by_kernel_commit bc8aeb04fd80 \
> +        "f2fs: fix to drop all discards after creating snapshot on lvm device"
> +
> +_require_scratch_nolvm
> +_require_block_device $SCRATCH_DEV
> +_require_command "$LVM_PROG" lvm
> +
> +lvname=lv_$sed
> +vgname=vg_$Sseg

What's "$sed" and "$Sseg", I didn't find the definition of them.

> +testfile=$SCRATCH_MNT/testfile
> +
> +_cleanup()
> +{

  _unmount $SCRATCH_MNT >>$seqres.full 2>&1

for this test might be interrupted.

> +	$LVM_PROG lvremove -f /dev/mapper/$lvname-snapshot $vgname >>$seqres.full 2>&1
> +	$LVM_PROG lvremove -f /dev/mapper/$vgname-$lvname >>$seqres.full 2>&1
> +	$LVM_PROG vgremove -f $vgname >>$seqres.full 2>&1
> +	$LVM_PROG pvremove -f $SCRATCH_DEV >>$seqres.full 2>&1

"-ff" might be better for cleanup.

According to 5f7a66b6dc4c ("fstests: use udevadm wait in preference to settle"), Dave
recommend doing below command after above lines:

  _udev_wait --removed /dev/mapper/$vgname-$lvname

Then, don't forget the default cleanup steps:

  cd /
  rm -f $tmp.*

> +}
> +
> +$LVM_PROG pvcreate -f $SCRATCH_DEV >>$seqres.full 2>&1
> +$LVM_PROG vgcreate -f $vgname $SCRATCH_DEV >>$seqres.full 2>&1
> +$LVM_PROG lvcreate -L 1024m -n $lvname $vgname >>$seqres.full 2>&1

Also according to 5f7a66b6dc4c ("fstests: use udevadm wait in preference to settle"),
Dave recommend using a:
  _udev_wait /dev/mapper/$vgname-$lvname

> +
> +$MKFS_F2FS_PROG /dev/mapper/$vgname-$lvname >>$seqres.full 2>&1

"-f" to force overwrite ? Or use _mkfs_dev? But _mkfs_dev doesn't has a f2f2
specific line, maybe you'd like to write one.

> +mount -o discard /dev/mapper/$vgname-$lvname $SCRATCH_MNT >>$seqres.full 2>&1

_mount

> +
> +dd if=/dev/zero of=$testfile bs=1M count=20 >>$seqres.full 2>&1
> +sync
> +rm $testfile

"-f" ?

> +sync
> +
> +# create a snapshot on lvm device
> +$LVM_PROG lvcreate -L 1024m -s -n $lvname-snapshot /dev/mapper/$vgname-$lvname >>$seqres.full 2>&1
> +umount $SCRATCH_MNT

Move this line to _cleanup, to always try to do it before removing lvm.

> +
> +echo "Silence is golden"
> +
> +status=0
> +exit
> diff --git a/tests/f2fs/008.out b/tests/f2fs/008.out
> new file mode 100644
> index 00000000..dd68d5a4
> --- /dev/null
> +++ b/tests/f2fs/008.out
> @@ -0,0 +1,2 @@
> +QA output created by 008
> +Silence is golden
> -- 
> 2.40.1
>