Re: [PATCH v2] /dev/zero: also implement ->read

[Christoph Hellwig <hch@lst.de>]

On Mon, Sep 07, 2020 at 10:21:14AM +0200, Greg KH wrote:
> On Mon, Sep 07, 2020 at 09:51:43AM +0200, Christoph Hellwig wrote:
> > Christophe reported a major speedup due to avoiding the iov_iter
> > overhead, so just add this trivial function.
> > 
> > Suggested-by: Christophe Leroy <christophe.leroy@csgroup.eu>
> > Signed-off-by: Christoph Hellwig <hch@lst.de>
> > Tested-by: Christophe Leroy <christophe.leroy@csgroup.eu>
> > ---
> > 
> > Changes since v1:
> >  - fix the Suggested-by: tag
> >  - report the actually read bytes in case of a partial clear_user
> >  - remove an impossible to hit conditional
> > 
> >  drivers/char/mem.c | 28 ++++++++++++++++++++++++++++
> >  1 file changed, 28 insertions(+)
> 
> I already merged your v1 into my tree, do you want me to revert that and
> then add this, or can you send me the diff to apply instead?  I can't
> rebase my public trees.

Sure, I can send an incremental one.  I vaguely remembered you as one
of the quilt holdouts.