Re: [PATCH v2 12/92] exfat: convert to simple_rename_timestamp

From: Jeff Layton
Date: Thu Jul 06 2023 - 07:41:23 EST


On Thu, 2023-07-06 at 12:39 +0200, Jan Kara wrote:
> On Wed 05-07-23 15:00:37, Jeff Layton wrote:
> > A rename potentially involves updating 4 different inode timestamps.
> > Convert to the new simple_rename_timestamp helper function.
> >
> > Signed-off-by: Jeff Layton <jlayton@xxxxxxxxxx>
> > ---
> > fs/exfat/namei.c | 5 ++---
> > 1 file changed, 2 insertions(+), 3 deletions(-)
> >
> > diff --git a/fs/exfat/namei.c b/fs/exfat/namei.c
> > index d9b46fa36bff..e91022ff80ef 100644
> > --- a/fs/exfat/namei.c
> > +++ b/fs/exfat/namei.c
> > @@ -1312,8 +1312,8 @@ static int exfat_rename(struct mnt_idmap *idmap,
> > goto unlock;
> >
> > inode_inc_iversion(new_dir);
> > - new_dir->i_ctime = new_dir->i_mtime = new_dir->i_atime =
> > - EXFAT_I(new_dir)->i_crtime = current_time(new_dir);
> > + simple_rename_timestamp(old_dir, old_dentry, new_dir, new_dentry);
> > + EXFAT_I(new_dir)->i_crtime = current_time(new_dir);
>
> Hum, you loose atime update with this. Not that it would make sense to have
> it but it would probably deserve a comment in the changelog.
>
> Also why you use current_time(new_dir) here instead of say inode->i_ctime?
>

I think the atime update there is a mistake. A rename is not a "read"
operation. I'll note it in the changelog.

The i_crtime in exfat is the creation time (aka btime). I don't think it
matters much which source that ultimately comes from, but now I'm
wondering why it gets set here at all. Does exfat create a new inode
during a rename? If not, then the i_crtime updates here should probably
be removed.


> > exfat_truncate_atime(&new_dir->i_atime);
> > if (IS_DIRSYNC(new_dir))
> > exfat_sync_inode(new_dir);
> > @@ -1336,7 +1336,6 @@ static int exfat_rename(struct mnt_idmap *idmap,
> > }
> >
> > inode_inc_iversion(old_dir);
> > - old_dir->i_ctime = old_dir->i_mtime = current_time(old_dir);
> > if (IS_DIRSYNC(old_dir))
> > exfat_sync_inode(old_dir);
> > else
>
> Also there is:
>
> new_inode->i_ctime = EXFAT_I(new_inode)->i_crtime =
> current_time(new_inode);
>
> in exfat_rename() from which you can remove the ctime update?
>

Yeah, that should be removed too. I'll fix that in my tree. The i_crtime
update here looks pretty suspicious too, fwiw.

Thanks!
--
Jeff Layton <jlayton@xxxxxxxxxx>