Re: [f2fs-dev] [PATCH] f2fs: fix quota info to adjust recovered data

From: Chao Yu
Date: Tue Sep 11 2018 - 22:57:55 EST


On 2018/9/12 10:46, Jaegeuk Kim wrote:
> On 09/12, Chao Yu wrote:
>> On 2018/9/12 9:25, Jaegeuk Kim wrote:
>>> On 09/12, Chao Yu wrote:
>>>> On 2018/9/12 8:27, Jaegeuk Kim wrote:
>>>>> On 09/11, Jaegeuk Kim wrote:
>>>>>> On 09/12, Chao Yu wrote:
>>>>>>> On 2018/9/12 4:15, Jaegeuk Kim wrote:
>>>>>>>> fsck.f2fs is able to recover the quota structure, since roll-forward recovery
>>>>>>>> can recover it based on previous user information.
>>>>>>>
>>>>>>> I didn't get it, both fsck and kernel recover quota file based all inodes'
>>>>>>> uid/gid/prjid, if {x}id didn't change, wouldn't those two recovery result be the
>>>>>>> same?
>>>>>>
>>>>>> I thought that, but had to add this, since I was encountering quota errors right
>>>>>> after getting some files recovered. And, I thought it'd make it more safe to do
>>>>>> fsck after roll-forward recovery.
>>>>>>
>>>>>> Anyway, let me test again without this patch for a while.
>>>>>
>>>>> Hmm, I just got a fsck failure right after some files recovered.
>>>>
>>>> To make sure, do you test with "f2fs: guarantee journalled quota data by
>>>> checkpoint"? if not, I think there is no guarantee that f2fs can recover
>>>> quote info into correct quote file, because, in last checkpoint, quota file
>>>> may was corrupted/inconsistent. Right?
>>
>> Oh, I forget to mention that, I add a patch to fsck to let it noticing
>> CP_QUOTA_NEED_FSCK_FLAG flag, and by default, fsck will fix corrupted quote
>> file if the flag is set, but w/o this flag, quota file is still corrupted
>> detected by fsck, I guess there is bug in v8.
>>
>> Can you add that in fsck too? so we can separate real kernel bug and quota
>> file corruption due to dquot subsystem error caused like below case:
>
> I'm testing to trigger fsck when it sees the below flag. But, when considering
> old f2fs-tools, we may need a way to detect mkfs version in superblock in order

Oh, that will make kernel be complicated... kernel should be aware of user
space things... if user use old tools and new kernel, how about just let
kernel give warning on dmesg to user to upgrade f2fs tool set.

And also, even if w/o CP_FSCK_FLAG, fsck can also detect such quote file
corruption, then do repair, right?

Thanks,

> to determine whether we can rely on this new flag or not.
>
>>
>> +static int f2fs_dquot_acquire(struct dquot *dquot)
>> +{
>> + int ret;
>> +
>> + ret = dquot_acquire(dquot);
>> + if (ret == -ENOSPC || ret == -EIO)
>> + set_sbi_flag(F2FS_SB(dquot->dq_sb), SBI_QUOTA_NEED_REPAIR);
>> + return ret;
>> +}
>>
>>>
>>> I hit the failure with v8. And, the test scenario is 1) enable fault injection
>>> 2) run fsstress, 3) call shutdowon, 4) kill fsstress, 5) unmount, 6) fsck, 7)
>>> mount, 8) fsck, 9) go 1).
>>>
>>> So, I'm hitting failure in 8) fsck. I expect 6) fsck should fix any corruption
>>> and 7) recovered some files on clean checkpoint.
>>
>> I see, I can add this case too, does this exist in your xfstest tree in github?
>
> I think so.
>
>>
>> Thanks,
>>
>>>
>>> Thanks,
>>>
>>>>
>>>> Thanks,
>>>>
>>>>>
>>>>>>
>>>>>> Thanks,
>>>>>>
>>>>>>
>>>>>>>
>>>>>>> Thanks,
>>>>>>>
>>>>>>>>
>>>>>>>> Signed-off-by: Jaegeuk Kim <jaegeuk@xxxxxxxxxx>
>>>>>>>> ---
>>>>>>>> fs/f2fs/recovery.c | 3 +++
>>>>>>>> 1 file changed, 3 insertions(+)
>>>>>>>>
>>>>>>>> diff --git a/fs/f2fs/recovery.c b/fs/f2fs/recovery.c
>>>>>>>> index 95511ed11a22..1fde86a2107e 100644
>>>>>>>> --- a/fs/f2fs/recovery.c
>>>>>>>> +++ b/fs/f2fs/recovery.c
>>>>>>>> @@ -675,6 +675,9 @@ int f2fs_recover_fsync_data(struct f2fs_sb_info *sbi, bool check_only)
>>>>>>>>
>>>>>>>> need_writecp = true;
>>>>>>>>
>>>>>>>> + /* quota is not fully updated due to the lack of user information. */
>>>>>>>> + set_sbi_flag(sbi, SBI_NEED_FSCK);
>>>>>>>> +
>>>>>>>> /* step #2: recover data */
>>>>>>>> err = recover_data(sbi, &inode_list, &dir_list);
>>>>>>>> if (!err)
>>>>>>>>
>>>>>>
>>>>>>
>>>>>> _______________________________________________
>>>>>> Linux-f2fs-devel mailing list
>>>>>> Linux-f2fs-devel@xxxxxxxxxxxxxxxxxxxxx
>>>>>> https://lists.sourceforge.net/lists/listinfo/linux-f2fs-devel
>>>>>
>>>>> .
>>>>>
>>>
>>> .
>>>
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> .
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