tree adb0d1d1343b8ca93dec9bf95a5263455371654a
parent 6dacfd2faa398dc5206523ae6a2f8dd037488de8
author Chris Wilson <chris@chris-wilson.co.uk> 1316002468 +0200
committer Keith Packard <keithp@keithp.com> 1319145079 -0700

drm/i915: Defend against userspace creating a gem object with size==0

We currently only round up the userspace size to the next page. We
assume that userspace hasn't made a mistake and requested a zero-length
gem object and all through our internal code we then presume that every
object is backed by at least a single page. Fix that oversight and
report EINVAL back to userspace if they try to create a zero length
object.

[danvet: This fixes tests/gem_bad_length]

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-Off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Reviewed-by: Ben Widawsky <ben@bwidawsk.net>
Signed-off-by: Keith Packard <keithp@keithp.com>