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

From: Chao Yu
Date: Tue Sep 11 2018 - 21:46:57 EST


On 2018/9/12 9:40, 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.

In v8, there are two cases we didn't guarantee quota file's consistence:
1. flush time in block_operation exceed a threshold.
2. dquot subsystem error occurs.

For above case, fsck should repair the quota file by default.

>
> 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:
>
> +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).

8) fsck is do fscking in a mounted image?

Thanks,

>>
>> 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?
>
> 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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