drm/i915: Check for get_pages instead of shmem (filp)

Ben Widawsky · danvet · commit 1db6e2e7dc27 · 2016-02-15T18:26:52.000+01:00
This behavior of checking for a shmem backed GEM object was introduced here: commit 4c914c0 Author: Brad Volkin <bradley.d.volkin@intel.com> Date: Tue Feb 18 10:15:45 2014 -0800 drm/i915: Refactor shmem pread setup It is possible for an object to not be a shmem backed GEM object (for example userptr objects). An example of how we hit this failure can be found through copy_batch() in the command parser because we allocate a userptr object for the batch which contains privileged instructions. Userptr calls drm_gem_private_object_init() which explicitly sets the filp to none. NOTE: I manually retyped this from a test machine. So I haven't even compiled this exact patch. v2: Use same logic as from a2a4f91 (Kristian, Dave Gordon) Cc: Chris Wilson <chris@chris-wilson.co.uk> Cc: Kristian Høgsberg <krh@bitplanet.net> Cc: Dave Gordon <david.s.gordon@intel.com> Signed-off-by: Ben Widawsky <benjamin.widawsky@intel.com> Tested-by: Jordan Justen <jordan.l.justen@intel.com> (v1) Reviewed-by: Jordan Justen <jordan.l.justen@intel.com> (v1) Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch> Link: http://patchwork.freedesktop.org/patch/msgid/1455047053-2644-1-git-send-email-benjamin.widawsky@intel.com
diff --git a/drivers/gpu/drm/i915/i915_gem.c b/drivers/gpu/drm/i915/i915_gem.c
@@ -489,7 +489,7 @@ int i915_gem_obj_prepare_shmem_read(struct drm_i915_gem_object *obj,
 
 	*needs_clflush = 0;
 
-	if (!obj->base.filp)
+	if (WARN_ON((obj->ops->flags & I915_GEM_OBJECT_HAS_STRUCT_PAGE) == 0))
 		return -EINVAL;
 
 	if (!(obj->base.read_domains & I915_GEM_DOMAIN_CPU)) {
