[Intel-gfx] [PATCH] drm/915: Pad GTT views of exec objects up to user specified size

[Chris Wilson]

On Thu, Oct 22, 2015 at 10:04:55AM +0200, Daniel Vetter wrote:
> On Wed, Oct 21, 2015 at 04:24:58PM +0100, Chris Wilson wrote:
> > Our GPUs impose certain requirements upon buffers that depend upon how
> > exactly they are used. Typically this is expressed as that they require
> > a larger surface than would be naively computed by pitch * height.
> > Normally such requirements are hidden away in the userspace driver, but
> > when we accept pointers from strangers and later impose extra conditions
> > on them, the original client allocator has no idea about the
> > monstrosities in the GPU and we require the userspace driver to inform
> > the kernel how many padding pages are required beyond the client
> > allocation.
> > 
> > v2: Long time, no see
> > 
> > Signed-off-by: Chris Wilson <chris at chris-wilson.co.uk>
> > Cc: Tvrtko Ursulin <tvrtko.ursulin at intel.com>
> 
> Usual "needs igt + open-source userspace" broken record from maintainer,
> in case someone really wants to use this. Noises I've heard is that it's
> for opencl, but who knows.

igt sent many, many months ago. My user, once again, is in policing
DRI3 and userptr.
-Chris

-- 
Chris Wilson, Intel Open Source Technology Centre