Re: [PATCH v3 1/9] fstests: add _loop_image_create_clone() helper

[Anand Jain <anajain.sg@gmail.com>]

On 28/4/26 02:31, Amir Goldstein wrote:
> On Mon, Apr 27, 2026 at 12:19 PM Anand Jain <asj@kernel.org> wrote:
>>
>> Introduce _loop_image_create_clone() and _loop_image_destroy() to mkfs an
>> image file and clone it to another image file, and attach a loop device to
>> them. And its destroy part.
>>
>> Signed-off-by: Anand Jain <asj@kernel.org>
>> ---
>>  common/rc | 44 ++++++++++++++++++++++++++++++++++++++++++++
>>  1 file changed, 44 insertions(+)
>>
>> diff --git a/common/rc b/common/rc
>> index 9632b211b58f..0e7b7eb1d98f 100644
>> --- a/common/rc
>> +++ b/common/rc
>> @@ -1503,6 +1503,50 @@ _scratch_resvblks()
>>         esac
>>  }
>>
>> +_loop_image_create_clone()
>> +{
>> +       local -n _ret=$1
>> +       local pre_clone_tune_func=$2
>> +       local img_file=$TEST_DIR/${seq}.img
>> +       local img_file_clone=$TEST_DIR/${seq}_clone.img
>> +       local size=$(_small_fs_size_mb 128) # Smallest possible
>> +       local loop_devs
>> +
>> +       size=$((size * 1024 * 1024))
>> +       $XFS_IO_PROG -f -c "truncate $size" $img_file
>> +
>> +       loop_devs=$(_create_loop_device $img_file)
>> +       _ret=($loop_devs)
>> +
>> +       case $FSTYP in
>> +       xfs)
>> +               _mkfs_dev "-s size=4096" $img_file
>> +               ;;
>> +       btrfs)
>> +               _mkfs_dev $img_file
>> +               ;;
>> +       *)
>> +               _mkfs_dev $img_file
> 
> You making a wrong assumption that FSTYP can format the loop devices
> 
> You should add _require_block_device $SCRATCH_DEV
> to all your tests or maybe nicer, add:
> 
> _require_loop_mountable which requires loop and block dev fs
> and use this requirement instead of just _require_loop in all tests.
> 

Thanks. I've fixed this in v4 by adding
  _require_block_device $TEST_DEV
Since SCRATCH_DEV is not required.

I didn't create a new _require_loop_mountable() helper.
Both _require_loop() and _require_block_device() are
used both together across other existing tests;
I prefer not to deviate into cleaning that up in this
patch set.

v4 is in the ML for rvb.

Thanks, Anand


> Thanks,
> Amir.