[LTP] [PATCH] lib/tst_device.c: Make sure all loop deivces fot test are detached

[Xiao Yang <yangx.jy@cn.fujitsu.com>]

On 2018/09/12 20:33, Cyril Hrubis wrote:
> Hi!
>> Running statx05 by runltp without -b option every time attached a loop
>> device but didn't detach it, as below:
>> ------------------------------------------------------------------
>> ...
>> tst_device.c:230: INFO: Using test device LTP_DEV='/dev/loop0'
>> tst_device.c:268: INFO: Skipping $LTP_DEV size 256MB, requested size 512MB
>> tst_device.c:83: INFO: Found free device '/dev/loop1'
>> tst_mkfs.c:83: INFO: Formatting /dev/loop1 with ext4 opts='' extra opts='-O encrypt'
>> ...
>> NAME       SIZELIMIT OFFSET AUTOCLEAR RO BACK-FILE                                         DIO
>> /dev/loop1         0      0         0  0 /tmp/ltp-gsrcFAkGpZ/Wka3bp/test_dev.img (deleted)   0
>> ------------------------------------------------------------------
>>
>> runltp created a block device with default 256M size by attaching a free loop
>> device and set LTP_DEV variable, but statx05 needed a 512M block device, so
>> tst_acquire_device__() in setup skipped the $LTP_DEV device and created another
>> block device with 512M size by attaching another free loop device.  Unfortunately,
>> tst_release_device() in cleanup cannot detach the 512M block device due to the
>> defined LTP_DEV.
> Btw his has been fixed for statx since:
>
> commit e583eacf3c9781116c19dec4c7e8c0aa4ed01ed5
> Author: Cyril Hrubis<chrubis@suse.cz>
> Date:   Tue Sep 11 17:27:43 2018 +0200
>
>      syscalls/statx05: Fix test on ppc64le
>
>
> But yes apart from that the test library is still broken.
>
>> We should just skip the detach in tst_release_device() when LTP_DEV variable is
>> set and device_acquired flag is not set.
>>
>> Signed-off-by: Xiao Yang<yangx.jy@cn.fujitsu.com>
>> ---
>>   lib/tst_device.c | 2 +-
>>   1 file changed, 1 insertion(+), 1 deletion(-)
>>
>> diff --git a/lib/tst_device.c b/lib/tst_device.c
>> index 463743443..23c99dba2 100644
>> --- a/lib/tst_device.c
>> +++ b/lib/tst_device.c
>> @@ -313,7 +313,7 @@ int tst_release_device(const char *dev)
>>   {
>>   	int ret;
>>
>> -	if (getenv("LTP_DEV"))
>> +	if (getenv("LTP_DEV")&&  !device_acquired)
>>   		return 0;
> I guess that this really should be just:
>
> 	if (!device_acquired)
> 		return 0;
Hi Cyril,

Thanks for yor review.
It seems better to me, and i will send the v2 patch.

Thanks,
Xiao Yang
> I will double check and test it later today.
>