Pretty soon only some drivers will need dev->struct_mutex in their
gem_free_object callbacks. Hence it's really important to make sure
everything still keeps getting this right.

v2: Don't check for locking before we check for non-NULL obj. Spotted
by Dan Carpenter.

Link: http://mid.gmane.org/1444894601-5200-10-git-send-email-daniel.vetter@ffwll.chReviewed-by: NDavid Herrmann <dh.herrmann@gmail.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@intel.com>

If kref_put_mutex returns true then the caller or the put function is responsible
for unlocking the mutex. The usual pattern assumes that the free
callback unlocks the mutex, but since that is shared with the locked
variant we need to explicitly unlock here.
Signed-off-by: NMaarten Lankhorst <maarten.lankhorst@linux.intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

This reverts commit 355a7018.

This had some bad side effects under normal operation, and should
have been dropped earlier.
Signed-off-by: NDave Airlie <airlied@redhat.com>

It happens on occasion that developers of generic user-space applications
abuse the dumb buffer API to get hold of drm buffers that they can both
mmap() and use for GPU acceleration, using the assumptions that dumb buffers
and buffers available for GPU are
a) The same type and can be aribtrarily type-casted.
b) fully coherent.

This patch makes the most widely used drivers warn nicely when that happens,
the next step will be to fail.

v2: Move drmP.h changes to drm_gem.h. Fix Radeon dumb mmap breakage.
Signed-off-by: NThomas Hellstrom <thellstrom@vmware.com>
Acked-by: NDaniel Vetter <daniel.vetter@ffwll.ch>
Acked-by: NAlex Deucher <alexander.deucher@amd.com>
Signed-off-by: NDave Airlie <airlied@redhat.com>

v2: Don't forget git add, noticed by David.

Cc: David Herrmann <dh.herrmann@gmail.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@intel.com>
Acked-by: NDavid Herrmann <dh.herrmann@gmail.com>
Acked-by: NAlex Deucher <alexander.deucher@amd.com>
Signed-off-by: NDave Airlie <airlied@redhat.com>