Re: [f2fs-dev] [PATCH] f2fs: return error number for quota_write

From: Jaegeuk Kim
Date: Tue Oct 17 2017 - 14:17:57 EST


On 10/17, Chao Yu wrote:
>
>
> On 2017/10/17 7:04, Jaegeuk Kim wrote:
> > On 10/16, Chao Yu wrote:
> >> Hi Jaegeuk,
> >>
> >> On 2017/10/13 7:15, Jaegeuk Kim wrote:
> >>> This patch returns an error number to quota_write in order for quota to handle
> >>> it correctly.
> >>
> >> We should return error number like __generic_file_write_iter, right? it
> >> needs to return written bytes if we have written one page or more, otherwise
> >> return error number feedbacked from write_begin.
> >>
> >> So how about reverting 4f31d26b0c17 ("f2fs: return wrong error number on
> >> f2fs_quota_write")?
> >
> > I thought like that, but realized the code change is somewhat different between
> > them.
>
> Hmm... main structure of codes here is copied from other file systems, is there
> the same problem in *_quota_write of other file systems?
>
> BTW, it looks making below judgment condition being useless.
>
> if (len == towrite)
> return 0;

We need this to avoid needless inode updates. :P

Thanks,

>
> Thanks,
>
> >
> > Thanks,
> >
> >>
> >> Thanks,
> >>
> >>>
> >>> Signed-off-by: Jaegeuk Kim <jaegeuk@xxxxxxxxxx>
> >>> ---
> >>> fs/f2fs/super.c | 5 ++++-
> >>> 1 file changed, 4 insertions(+), 1 deletion(-)
> >>>
> >>> diff --git a/fs/f2fs/super.c b/fs/f2fs/super.c
> >>> index 2feecf5e7f4c..840a0876005b 100644
> >>> --- a/fs/f2fs/super.c
> >>> +++ b/fs/f2fs/super.c
> >>> @@ -1397,8 +1397,11 @@ static ssize_t f2fs_quota_write(struct super_block *sb, int type,
> >>>
> >>> err = a_ops->write_begin(NULL, mapping, off, tocopy, 0,
> >>> &page, NULL);
> >>> - if (unlikely(err))
> >>> + if (unlikely(err)) {
> >>> + if (len == towrite)
> >>> + return err;
> >>> break;
> >>> + }
> >>>
> >>> kaddr = kmap_atomic(page);
> >>> memcpy(kaddr + offset, data, tocopy);
> >>>
> >
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