Re: [PATCH] xfs: test xfs_growfs with too-small size expansion

[David Disseldorp <ddiss@suse.de>]

Looks fine.
Reviewed-by: David Disseldorp <ddiss@suse.de>

A couple of minor comments below...

On Sun, 28 Jan 2024 23:56:53 +0800, Zorro Lang wrote:

> This's a regression test of 84712492e6da ("xfs: short circuit
> xfs_growfs_data_private() if delta is zero").
> 
> If try to do growfs with "too-small" size expansion, might lead to a
> delta of "0" in xfs_growfs_data_private(), then end up in the shrink
> case and emit the EXPERIMENTAL warning even if we're not changing
> anything at all.
> 
> Signed-off-by: Zorro Lang <zlang@redhat.com>
> ---
>  tests/xfs/999     | 53 +++++++++++++++++++++++++++++++++++++++++++++++
>  tests/xfs/999.out |  2 ++
>  2 files changed, 55 insertions(+)
>  create mode 100755 tests/xfs/999
>  create mode 100644 tests/xfs/999.out
> 
> diff --git a/tests/xfs/999 b/tests/xfs/999
> new file mode 100755
> index 00000000..09192ba3
> --- /dev/null
> +++ b/tests/xfs/999
> @@ -0,0 +1,53 @@
> +#! /bin/bash
> +# SPDX-License-Identifier: GPL-2.0
> +# Copyright (c) 2024 Red Hat, Inc.  All Rights Reserved.
> +#
> +# FS QA Test No. 999

I'll assume 999 is just a placeholder...

> +#
> +# Test xfs_growfs with "too-small" size expansion, which lead to a delta of "0"
> +# in xfs_growfs_data_private. This's a regression test of 84712492e6da ("xfs:
> +# short circuit xfs_growfs_data_private() if delta is zero").
> +#
> +. ./common/preamble
> +_begin_fstest auto quick growfs
> +
> +_cleanup()
> +{
> +	local dev
> +        $UMOUNT_PROG $LOOP_MNT 2>/dev/null
> +	dev=$(losetup -j testfile | cut -d: -f1)
> +	losetup -d $dev 2>/dev/null
> +        rm -rf $LOOP_IMG $LOOP_MNT
> +        cd /
> +        rm -f $tmp.*

nit: tabs and spaces mixed above

> +}
> +
> +# real QA test starts here
> +_supported_fs xfs
> +_fixed_by_kernel_commit 84712492e6da \
> +	"xfs: short circuit xfs_growfs_data_private() if delta is zero"
> +_require_test
> +_require_loop
> +_require_xfs_io_command "truncate"

nit: it doesn't seem common for growfs, but you might want to add a:
  _require_command "$XFS_GROWFS_PROG" xfs_growfs