tree ee772a48d1320e9f75c09fe278d3887bc70dbf5b
parent 46a55d3016083bf43568a6a20ad95567fb79202d
author Chris Wilson <chris@chris-wilson.co.uk> 1400746612 +0100
committer Daniel Vetter <daniel.vetter@ffwll.ch> 1400763994 +0200

drm/i915: Only discard backing storage on releasing the last ref

Before purging our pages (as opposed to copying back the contents from
the GPU), make sure that there is not an exposed CPU mmapping through
which the user can inspect the results.

Regression from

commit 5537252b6b6d71fb1a8ed7395a8e5babf91953fd
Author: Chris Wilson <chris@chris-wilson.co.uk>
Date:   Tue Mar 25 13:23:06 2014 +0000

    drm/i915: Invalidate our pages under memory pressure

Testcase: igt/gem_mmap/new-object
Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=79005
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Tested-by: Guo Jinxian <jinxianx.guo@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>