drm/i915: Getter/setter for object attributes

Soon we want to gut a lot of our existing assumptions how many address
spaces an object can live in, and in doing so, embed the drm_mm_node in
the object (and later the VMA).

It's possible in the future we'll want to add more getter/setter
methods, but for now this is enough to enable the VMAs.

v2: Reworked commit message (Ben)
Added comments to the main functions (Ben)
sed -i "s/i915_gem_obj_set_color/i915_gem_obj_ggtt_set_color/" drivers/gpu/drm/i915/*.[ch]
sed -i "s/i915_gem_obj_bound/i915_gem_obj_ggtt_bound/" drivers/gpu/drm/i915/*.[ch]
sed -i "s/i915_gem_obj_size/i915_gem_obj_ggtt_size/" drivers/gpu/drm/i915/*.[ch]
sed -i "s/i915_gem_obj_offset/i915_gem_obj_ggtt_offset/" drivers/gpu/drm/i915/*.[ch]
(Daniel)

v3: Rebased on new reserve_node patch
Changed DRM_DEBUG_KMS to actually work (will need fixing later)

Signed-off-by: Ben Widawsky <ben@bwidawsk.net>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
diff --git a/drivers/gpu/drm/i915/i915_drv.h b/drivers/gpu/drm/i915/i915_drv.h
index 0a91554..8a92174 100644
--- a/drivers/gpu/drm/i915/i915_drv.h
+++ b/drivers/gpu/drm/i915/i915_drv.h
@@ -1361,6 +1361,37 @@
 
 #define to_intel_bo(x) container_of(x, struct drm_i915_gem_object, base)
 
+/* Offset of the first PTE pointing to this object */
+static inline unsigned long
+i915_gem_obj_ggtt_offset(struct drm_i915_gem_object *o)
+{
+	return o->gtt_space->start;
+}
+
+/* Whether or not this object is currently mapped by the translation tables */
+static inline bool
+i915_gem_obj_ggtt_bound(struct drm_i915_gem_object *o)
+{
+	return o->gtt_space != NULL;
+}
+
+/* The size used in the translation tables may be larger than the actual size of
+ * the object on GEN2/GEN3 because of the way tiling is handled. See
+ * i915_gem_get_gtt_size() for more details.
+ */
+static inline unsigned long
+i915_gem_obj_ggtt_size(struct drm_i915_gem_object *o)
+{
+	return o->gtt_space->size;
+}
+
+static inline void
+i915_gem_obj_ggtt_set_color(struct drm_i915_gem_object *o,
+			    enum i915_cache_level color)
+{
+	o->gtt_space->color = color;
+}
+
 /**
  * Request queue structure.
  *