[PATCH 2/2] drm/etnaviv: User FOLL_LONGTERM in userptr

[Daniel Vetter]

On Mon, Mar 01, 2021 at 02:26:01AM -0800, John Hubbard wrote:
> On 3/1/21 01:52, Daniel Vetter wrote:
> > There's no mmu notifier or anything like that, releasing this pin is
> > entirely up to userspace. Hence FOLL_LONGTERM.
> > 
> > No cc: stable for this patch since a lot of the infrastructure around
> > FOLL_LONGETRM (like not allowing it for pages currently sitting in
> 
>   ^FOLL_LONGTERM
> 
> > ZONE_MOVEABLE before they're migrated) is still being worked on. So
> > not big benefits yet.
> 
> Yes. Great write-up, that's very clear, and it's exactly where we're at.
> 
> Reviewed-by: John Hubbard <jhubbard at nvidia.com>

Both patches pushed to drm-misc-fixes. 2nd one maybe not required there,
but easier due to conflicts.

Thanks for the review.
-Daniel

> 
> 
> thanks,
> -- 
> John Hubbard
> NVIDIA
> 
> > 
> > Cc: John Hubbard <jhubbard at nvidia.com>
> > Signed-off-by: Daniel Vetter <daniel.vetter at intel.com>
> > Cc: Lucas Stach <l.stach at pengutronix.de>
> > Cc: Russell King <linux+etnaviv at armlinux.org.uk>
> > Cc: Christian Gmeiner <christian.gmeiner at gmail.com>
> > Cc: etnaviv at lists.freedesktop.org
> > ---
> >   drivers/gpu/drm/etnaviv/etnaviv_gem.c | 3 ++-
> >   1 file changed, 2 insertions(+), 1 deletion(-)
> > 
> > diff --git a/drivers/gpu/drm/etnaviv/etnaviv_gem.c b/drivers/gpu/drm/etnaviv/etnaviv_gem.c
> > index a9e696d05b33..db69f19ab5bc 100644
> > --- a/drivers/gpu/drm/etnaviv/etnaviv_gem.c
> > +++ b/drivers/gpu/drm/etnaviv/etnaviv_gem.c
> > @@ -689,7 +689,8 @@ static int etnaviv_gem_userptr_get_pages(struct etnaviv_gem_object *etnaviv_obj)
> >   		struct page **pages = pvec + pinned;
> >   		ret = pin_user_pages_fast(ptr, num_pages,
> > -					  FOLL_WRITE | FOLL_FORCE, pages);
> > +					  FOLL_WRITE | FOLL_FORCE | FOLL_LONGTERM,
> > +					  pages);
> >   		if (ret < 0) {
> >   			unpin_user_pages(pvec, pinned);
> >   			kvfree(pvec);
> > 

-- 
Daniel Vetter
Software Engineer, Intel Corporation
http://blog.ffwll.ch