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

From: Jaegeuk Kim
Date: Mon Sep 17 2018 - 22:06:04 EST


On 09/18, Chao Yu wrote:
> On 2018/9/18 9:19, Jaegeuk Kim wrote:
> > On 09/13, Chao Yu wrote:
> >> On 2018/9/13 3:54, Jaegeuk Kim wrote:
> >>> On 09/12, Chao Yu wrote:
> >>>> 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.
> >>>
> >>> Okay, I got another failure and it seems CP_QUOTA_NEED_FSCK_FLAG was not set
> >>> during the recovery. So, we have something missing in the recovery in terms
> >>> of quota updates.
> >>
> >> Yeah, I checked the code, just found one suspected place:
> >>
> >> find_fsync_dnodes()
> >> - f2fs_recover_inode_page
> >> - inc_valid_node_count
> >> - dquot_reserve_block dquot info is not initialized now
> >> - add_fsync_inode
> >> - dquot_initialize
> >>
> >> I think we should reserve block for inode block after dquot_initialize(), can
> >> you confirm this?
> >
> > Let me test this.
> >
> >>From b90260bc577fe87570b1ef7b134554a8295b1f6c Mon Sep 17 00:00:00 2001
> > From: Jaegeuk Kim <jaegeuk@xxxxxxxxxx>
> > Date: Mon, 17 Sep 2018 18:14:41 -0700
> > Subject: [PATCH] f2fs: count inode block for recovered files
> >
> > If a new file is recovered, we missed to reserve its inode block.
>
> I remember, in order to keep line with other filesystem, unlike on-disk, we
> have to keep backward compatibilty, in memory we don't account block number
> for f2fs' inode block, but only account inode number for it, so here like
> we did in inc_valid_node_count(), we don't need to do this.

Okay, I just hit the error again w/o your patch. Another one coming to my mind
is that caused by uid/gid change during recovery. Let me try out your patch.

>
> Can you test v9 first? I didn't encounter quota corruption with your
> testcase right now. Will check it in cell phone environment.
>
> >
> > Signed-off-by: Chao Yu <yuchao0@xxxxxxxxxx>
> > Signed-off-by: Jaegeuk Kim <jaegeuk@xxxxxxxxxx>
> > ---
> > fs/f2fs/recovery.c | 5 +++++
> > 1 file changed, 5 insertions(+)
> >
> > diff --git a/fs/f2fs/recovery.c b/fs/f2fs/recovery.c
> > index 56d34193a74b..bff5cf730e13 100644
> > --- a/fs/f2fs/recovery.c
> > +++ b/fs/f2fs/recovery.c
> > @@ -84,6 +84,11 @@ static struct fsync_inode_entry *add_fsync_inode(struct f2fs_sb_info *sbi,
> > err = dquot_alloc_inode(inode);
> > if (err)
> > goto err_out;
> > + err = dquot_reserve_block(inode, 1);
> > + if (err) {
> > + dquot_drop(inode);
> > + goto err_out;
> > + }
> > }
> >
> > entry = f2fs_kmem_cache_alloc(fsync_entry_slab, GFP_F2FS_ZERO);
> >