tree a58dca612ff402b33b63b678e7ebb841ea731b29
parent 4d884705dababd7d0f3f12796bc7b45e84962596
author Daniel Vetter <daniel.vetter@ffwll.ch> 1407330288 +0200
committer Daniel Vetter <daniel.vetter@ffwll.ch> 1407932609 +0200

drm/i915: Only refcount ppgtt if it actually is one

This essentially unbreaks non-ppgtt operation where we'd scribble over
random memory.

While at it give the vm_to_ppgtt function a proper prefix and make it
a bit more paranoid.

Reviewed-by: Michel Thierry <michel.thierry@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>