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From:   =?UTF-8?Q?Andreas_Gr=C3=BCnbacher?= <andreas.gruenbacher@gmail.com>
Date:   Thu, 6 Jul 2023 01:19:33 +0200
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Subject: Re: [PATCH 7/9] gfs2: update ctime when quota is updated
To:     Jeff Layton <jlayton@kernel.org>
Cc:     Andreas Gruenbacher <agruenba@redhat.com>,
        Christian Brauner <brauner@kernel.org>,
        Al Viro <viro@zeniv.linux.org.uk>,
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Am Mi., 5. Juli 2023 um 23:51 Uhr schrieb Jeff Layton <jlayton@kernel.org>:
>
> On Wed, 2023-07-05 at 22:25 +0200, Andreas Gruenbacher wrote:
> > On Mon, Jun 12, 2023 at 12:36=E2=80=AFPM Jeff Layton <jlayton@kernel.or=
g> wrote:
> > > On Fri, 2023-06-09 at 18:44 +0200, Andreas Gruenbacher wrote:
> > > > Jeff,
> > > >
> > > > On Fri, Jun 9, 2023 at 2:50=E2=80=AFPM Jeff Layton <jlayton@kernel.=
org> wrote:
> > > > > Signed-off-by: Jeff Layton <jlayton@kernel.org>
> > > > > ---
> > > > >  fs/gfs2/quota.c | 2 +-
> > > > >  1 file changed, 1 insertion(+), 1 deletion(-)
> > > > >
> > > > > diff --git a/fs/gfs2/quota.c b/fs/gfs2/quota.c
> > > > > index 1ed17226d9ed..6d283e071b90 100644
> > > > > --- a/fs/gfs2/quota.c
> > > > > +++ b/fs/gfs2/quota.c
> > > > > @@ -869,7 +869,7 @@ static int gfs2_adjust_quota(struct gfs2_inod=
e *ip, loff_t loc,
> > > > >                 size =3D loc + sizeof(struct gfs2_quota);
> > > > >                 if (size > inode->i_size)
> > > > >                         i_size_write(inode, size);
> > > > > -               inode->i_mtime =3D inode->i_atime =3D current_tim=
e(inode);
> > > > > +               inode->i_mtime =3D inode->i_atime =3D inode->i_ct=
ime =3D current_time(inode);
> > > >
> > > > I don't think we need to worry about the ctime of the quota inode a=
s
> > > > that inode is internal to the filesystem only.
> > > >
> > >
> > > Thanks Andreas.  I'll plan to drop this patch from the series for now=
.
> > >
> > > Does updating the mtime and atime here serve any purpose, or should
> > > those also be removed? If you plan to keep the a/mtime updates then I=
'd
> > > still suggest updating the ctime for consistency's sake. It shouldn't
> > > cost anything extra to do so since you're dirtying the inode below
> > > anyway.
> >
> > Yes, good point actually, we should keep things consistent for simplici=
ty.
> >
> > Would you add this back in if you do another posting?
> >
>
> I just re-posted the other patches in this as part of the ctime accessor
> conversion. If I post again though, I can resurrect the gfs2 patch. If
> not, we can do a follow-on fix later.

Sure, not a big deal.

> Since we're discussing it, it may be more correct to remove the atime
> update there. gfs2_adjust_quota sounds like a "modify" operation, not a
> "read", so I don't see a reason to update the atime.
>
> In general, the only time you only want to set the atime, ctime and
> mtime in lockstep is when the inode is brand new.

Yes, that makes sense, too.

Thanks,
Andreas