Re: [PATCH 1/2] xfs: add mount test for read only rt devices

[Hans Holmberg <Hans.Holmberg@wdc.com>]

On 25/04/2025 17:04, Darrick J. Wong wrote:
> On Fri, Apr 25, 2025 at 09:03:22AM +0000, Hans Holmberg wrote:
>> Make sure that we can mount rt devices read-only if them themselves
>> are marked as read-only.
>>
>> Also make sure that rw re-mounts are not allowed if the device is
>> marked as read-only.
>>
>> Based on generic/050.
>>
>> Signed-off-by: Hans Holmberg <hans.holmberg@wdc.com>
>> ---
>>  tests/xfs/837     | 55 +++++++++++++++++++++++++++++++++++++++++++++++
>>  tests/xfs/837.out | 10 +++++++++
>>  2 files changed, 65 insertions(+)
>>  create mode 100755 tests/xfs/837
>>  create mode 100644 tests/xfs/837.out
>>
>> diff --git a/tests/xfs/837 b/tests/xfs/837
>> new file mode 100755
>> index 000000000000..b20e9c5f33f2
>> --- /dev/null
>> +++ b/tests/xfs/837
>> @@ -0,0 +1,55 @@
>> +#! /bin/bash
>> +# SPDX-License-Identifier: GPL-2.0
>> +# Copyright (c) 2009 Christoph Hellwig.
>> +# Copyright (c) 2025 Western Digital Corporation
>> +#
>> +# FS QA Test No. 837
>> +#
>> +# Check out various mount/remount/unmount scenarious on a read-only rtdev
>> +# Based on generic/050
>> +#
>> +. ./common/preamble
>> +_begin_fstest mount auto quick
>> +
>> +_cleanup_setrw()
>> +{
>> +	cd /
>> +	blockdev --setrw $SCRATCH_RTDEV
>> +}
>> +
>> +# Import common functions.
>> +. ./common/filter
>> +
>> +_require_realtime
>> +_require_local_device $SCRATCH_RTDEV
> 
> I suspect this is copy-pasted from generic/050, but I wonder when
> SCRATCH_RTDEV could be a character device, but maybe that's a relic of
> Irix (and Solaris too, IIRC)?

Yeah, this was carried over from generic/050, and I can just drop it
unless there is a good reason for keeping it?

<pardon replying again Darrick, forgot to reply-all yesterday>

> 
> The rest of the test looks fine to me though.
> 
> --D
> 
>> +_register_cleanup "_cleanup_setrw"
>> +
>> +_scratch_mkfs "-d rtinherit" > /dev/null 2>&1
>> +
>> +#
>> +# Mark the rt device read-only.
>> +#
>> +echo "setting device read-only"
>> +blockdev --setro $SCRATCH_RTDEV
>> +
>> +#
>> +# Mount it and make sure it can't be written to.
>> +#
>> +echo "mounting read-only rt block device:"
>> +_scratch_mount 2>&1 | _filter_ro_mount | _filter_scratch
>> +if [ "${PIPESTATUS[0]}" -eq 0 ]; then
>> +	echo "writing to file on read-only filesystem:"
>> +	dd if=/dev/zero of=$SCRATCH_MNT/foo bs=1M count=1 oflag=direct 2>&1 | _filter_scratch
>> +else
>> +	_fail "failed to mount"
>> +fi
>> +
>> +echo "remounting read-write:"
>> +_scratch_remount rw 2>&1 | _filter_scratch | _filter_ro_mount
>> +
>> +echo "unmounting read-only filesystem"
>> +_scratch_unmount 2>&1 | _filter_scratch | _filter_ending_dot
>> +
>> +# success, all done
>> +echo "*** done"
>> +status=0
>> diff --git a/tests/xfs/837.out b/tests/xfs/837.out
>> new file mode 100644
>> index 000000000000..0a843a0ba398
>> --- /dev/null
>> +++ b/tests/xfs/837.out
>> @@ -0,0 +1,10 @@
>> +QA output created by 837
>> +setting device read-only
>> +mounting read-only rt block device:
>> +mount: device write-protected, mounting read-only
>> +writing to file on read-only filesystem:
>> +dd: failed to open 'SCRATCH_MNT/foo': Read-only file system
>> +remounting read-write:
>> +mount: cannot remount device read-write, is write-protected
>> +unmounting read-only filesystem
>> +*** done
>> -- 
>> 2.34.1
>>
>