Re: [PATCH v2 04/12] fat: only specify I_DIRTY_TIME when needed in fat_update_time()

Christoph Hellwig
2021-01-12T13:24:01Z

On Mon, Jan 11, 2021 at 11:50:27AM -0800, Eric Biggers wrote:
> On Mon, Jan 11, 2021 at 11:52:01AM +0100, Christoph Hellwig wrote:
> > On Fri, Jan 08, 2021 at 11:58:55PM -0800, Eric Biggers wrote:
> > > + if ((flags & S_VERSION) && inode_maybe_inc_iversion(inode, false))
> > > + dirty_flags |= I_DIRTY_SYNC;
> >
> > fat does not support i_version updates, so this bit can be skipped.
>
> Is that really the case? Any filesystem (including fat) can be mounted with
> "iversion", which causes SB_I_VERSION to be set.
>
> A lot of filesystems (including fat) don't store i_version to disk, but it looks
> like it will still get updated in-memory. Could anything be relying on that?

As Dave pointed out i_version can't really work for fat. But I guess
that is indeed out of scope for this series, so let's go ahead with this
version for now:

Reviewed-by: Christoph Hellwig <hch@lst.de>