Re: [PATCH] fstests: verify that xfs_growfs can operate on mounted device node

[Eryu Guan <guaneryu@gmail.com>]

On Tue, Oct 29, 2019 at 12:53:48PM -0500, Eric Sandeen wrote:
> The ability to use a mounted device node as the primary argument
> to xfs_growfs will be added back in, because it was an undocumented
> behavior that some userspace depended on.  This test exercises that
> functionality.
> 
> Signed-off-by: Eric Sandeen <sandeen@redhat.com>
> ---
> 
> diff --git a/tests/xfs/148 b/tests/xfs/148
> new file mode 100755
> index 00000000..357ae01c
> --- /dev/null
> +++ b/tests/xfs/148
> @@ -0,0 +1,100 @@
> +#! /bin/bash
> +# SPDX-License-Identifier: GPL-2.0
> +# Copyright (c) 2019 Red Hat, Inc.  All Rights Reserved.
> +#
> +# FS QA Test 148
> +#
> +# Test to ensure xfs_growfs command accepts device nodes if & only
> +# if they are mounted.
> +# This functionality, though undocumented, worked until xfsprogs v4.12
> +# It was added back and documented after xfsprogs v5.2

I'm testing with xfsprogs from for-next branch, which is v5.3.0-rc1
based xfs_growfs, but I still see failures like

     === xfs_growfs - check device node ===
    +xfs_growfs: /dev/loop0 is not a mounted XFS filesystem
     === xfs_growfs - check device symlink ===
    +xfs_growfs: /mnt/test/loop_symlink.21781 is not a mounted XFS filesystem
     === unmount ===

If it's already fixed, would you please list the related commits in
commit log as well?

> +#
> +# Based on xfs/289
> +#
> +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()
> +{
> +    $UMOUNT_PROG $mntdir
> +    _destroy_loop_device $loop_dev
> +    rmdir $mntdir
> +    rm -f $loop_symlink
> +    rm -f $loopfile
> +}

'mntdir', 'loop_symlink' and 'loopfile' should be defined before
_cleanup, otherwise if we exit early, e.g. due to unmet requirement,
we'll see false failures.

And should check if 'loop_dev' is defined before destroy it.

> +
> +# get standard environment, filters and checks
> +. ./common/rc
> +. ./common/filter
> +
> +# remove previous $seqres.full before test
> +rm -f $seqres.full
> +
> +# real QA test starts here
> +
> +# Modify as appropriate.
> +_supported_fs xfs
> +_supported_os Linux
> +_require_test
> +_require_loop
> +
> +loopfile=$TEST_DIR/fsfile
> +mntdir=$TEST_DIR/mntdir
> +loop_symlink=$TEST_DIR/loop_symlink.$$
> +
> +mkdir -p $mntdir || _fail "!!! failed to create temp mount dir"
> +
> +echo "=== mkfs.xfs ==="
> +$MKFS_XFS_PROG -d file,name=$loopfile,size=16m -f >/dev/null 2>&1
> +
> +echo "=== truncate ==="
> +$XFS_IO_PROG -fc "truncate 256m" $loopfile
> +
> +echo "=== create loop device ==="
> +loop_dev=$(_create_loop_device $loopfile)
> +
> +echo "=== create loop device symlink ==="
> +ln -s $loop_dev $loop_symlink
> +
> +echo "loop device is $loop_dev"

This should be redirected to $seqres.full, as $loop_dev could be any
loop device.

> +
> +# These unmounted operations should fail
> +
> +echo "=== xfs_growfs - unmounted device, command should be rejected ==="
> +$XFS_GROWFS_PROG $loop_dev 2>&1 | sed -e s:$loop_dev:LOOPDEV:
> +
> +echo "=== xfs_growfs - check symlinked dev, unmounted ==="
> +$XFS_GROWFS_PROG $loop_symlink 2>&1 | sed -e s:$loop_symlink:LOOPSYMLINK:
> +
> +# These mounted operations should pass
> +
> +echo "=== mount ==="
> +$MOUNT_PROG $loop_dev $mntdir || _fail "!!! failed to loopback mount"
> +
> +echo "=== xfs_growfs - check device node ==="
> +$XFS_GROWFS_PROG -D 8192 $loop_dev > /dev/null
> +
> +echo "=== xfs_growfs - check device symlink ==="
> +$XFS_GROWFS_PROG -D 12288 $loop_symlink > /dev/null
> +
> +echo "=== unmount ==="
> +$UMOUNT_PROG $mntdir || _fail "!!! failed to unmount"
> +
> +echo "=== mount device symlink ==="
> +$MOUNT_PROG $loop_symlink $mntdir || _fail "!!! failed to loopback mount"
> +
> +echo "=== xfs_growfs - check device symlink ==="
> +$XFS_GROWFS_PROG -D 16384 $loop_symlink > /dev/null
> +
> +echo "=== xfs_growfs - check device node ==="
> +$XFS_GROWFS_PROG -D 20480 $loop_dev > /dev/null
> +
> +# success, all done
> +status=0
> +exit
> diff --git a/tests/xfs/148.out b/tests/xfs/148.out
> new file mode 100644
> index 00000000..d8e6f02d
> --- /dev/null
> +++ b/tests/xfs/148.out
> @@ -0,0 +1,17 @@
> +QA output created by 148
> +=== mkfs.xfs ===
> +=== truncate ===
> +=== create loop device ===
> +=== create loop device symlink ===
> +loop device is /dev/loop0

So this line should be removed as well.

Thanks,
Eryu

> +=== xfs_growfs - unmounted device, command should be rejected ===
> +xfs_growfs: LOOPDEV is not a mounted XFS filesystem
> +=== xfs_growfs - check symlinked dev, unmounted ===
> +xfs_growfs: LOOPSYMLINK is not a mounted XFS filesystem
> +=== mount ===
> +=== xfs_growfs - check device node ===
> +=== xfs_growfs - check device symlink ===
> +=== unmount ===
> +=== mount device symlink ===
> +=== xfs_growfs - check device symlink ===
> +=== xfs_growfs - check device node ===
> diff --git a/tests/xfs/group b/tests/xfs/group
> index f4ebcd8c..40a61b55 100644
> --- a/tests/xfs/group
> +++ b/tests/xfs/group
> @@ -145,6 +145,7 @@
>  145 dmapi
>  146 dmapi
>  147 dmapi
> +148 quick auto growfs
>  150 dmapi
>  151 dmapi
>  152 dmapi
>