Re: [PATCH] direct-io: allow direct writes to empty inodes

["Ernesto A. Fernández" <ernesto.mnd.fernandez@gmail.com>]

On Mon, Jan 07, 2019 at 03:03:08PM -0300, Ernesto A. Fernández wrote:
> On Sat, Oct 27, 2018 at 10:54:09AM -0600, Jens Axboe wrote:
> > On 10/26/18 10:12 PM, Ernesto A. Fernández wrote:
> > > On Fri, Oct 26, 2018 at 08:29:00AM -0600, Jens Axboe wrote:
> > >> On 10/26/18 3:30 AM, Jan Kara wrote:
> > >>> On Mon 08-10-18 20:58:23, Ernesto A. Fernández wrote:
> > >>>> On a DIO_SKIP_HOLES filesystem, the ->get_block() method is currently
> > >>>> not allowed to create blocks for an empty inode.  This confusion comes
> > >>>> from trying to bit shift a negative number, so check the size of the
> > >>>> inode first.
> > >>>>
> > >>>> The problem is most visible for hfsplus, because the fallback to
> > >>>> buffered I/O doesn't happen and the write fails with EIO.  This is in
> > >>>> part the fault of the module, because it gives a wrong return value on
> > >>>> ->get_block(); that will be fixed in a separate patch.
> > >>>>
> > >>>> Signed-off-by: Ernesto A. Fernández <ernesto.mnd.fernandez@gmail.com>
> > >>>
> > >>> Good catch. The patch looks good. You can add:
> > >>>
> > >>> Reviewed-by: Jan Kara <jack@suse.cz>
> > >>>
> > >>> Also Jens often picks up patches for direct IO code so added him to CC.
> > >>> Jens?
> > >>
> > >> Looks good to me. Ernesto, did you run this through xfstests as well?
> > > 
> > > I only ran the quick tests for ext2.  Also for hfsplus, but those are not
> > > very meaningful because too many are failing.
> > 
> > OK, that's useful. I'll run it through the whole thing just in case,
> > but I don't expect to find anything.
> 
> So what happened with this patch?  Any issues?

Ping?

> 
> > 
> > -- 
> > Jens Axboe
> >