drm/i915: Round-up GTT allocations for unfenced surfaces to the next tile row

Commit Message

Chris Wilson March 25, 2011, 9:36 a.m. UTC

None

Patch

diff --git a/drivers/gpu/drm/i915/i915_drv.h b/drivers/gpu/drm/i915/i915_drv.h
index 787c969..359ddce 100644
--- a/drivers/gpu/drm/i915/i915_drv.h
+++ b/drivers/gpu/drm/i915/i915_drv.h
@@ -1183,6 +1183,8 @@  void i915_gem_free_all_phys_object(struct drm_device *dev);
 void i915_gem_release(struct drm_device *dev, struct drm_file *file);
 
 uint32_t
+i915_gem_get_unfenced_gtt_size(struct drm_i915_gem_object *obj);
+uint32_t
 i915_gem_get_unfenced_gtt_alignment(struct drm_i915_gem_object *obj);
 
 /* i915_gem_gtt.c */
diff --git a/drivers/gpu/drm/i915/i915_gem.c b/drivers/gpu/drm/i915/i915_gem.c
index 0012061..3e483c5 100644
--- a/drivers/gpu/drm/i915/i915_gem.c
+++ b/drivers/gpu/drm/i915/i915_gem.c
@@ -1427,6 +1427,35 @@  i915_gem_get_gtt_alignment(struct drm_i915_gem_object *obj)
 }
 
 /**
+ * i915_gem_get_unfenced_gtt_size - return required GTT size for an
+ *				    unfenced object
+ * @obj: object to check
+ *
+ * Return the required GTT size for an object, only taking into account
+ * unfenced tiled surface requirements.
+ */
+uint32_t
+i915_gem_get_unfenced_gtt_size(struct drm_i915_gem_object *obj)
+{
+	u32 unfenced_alignment;
+
+	/*
+	 * Current userspace will attempt to overallocate a bo so that it
+	 * can be reused with another surface and so its size is unlikely
+	 * to be an exact number of tile rows - but it promised never to
+	 * access beyond the end of the last complete row.
+	 *
+	 * gen2 has a futher restriction, in that it requires an even number
+	 * of tiles rows. Userspace was not aware of this until recently
+	 * and so violated its promise to always allocate enough pages
+	 * for the hardware. In reply, we now always round up the GTT
+	 * allocation to the next [even] tile row.
+	 */
+	unfenced_alignment = i915_gem_get_unfenced_gtt_alignment(obj);
+	return ALIGN(obj->base.size, unfenced_alignment);
+}
+
+/**
  * i915_gem_get_unfenced_gtt_alignment - return required GTT alignment for an
  *					 unfenced object
  * @obj: object to check
@@ -2744,7 +2773,8 @@  i915_gem_object_bind_to_gtt(struct drm_i915_gem_object *obj,
 	drm_i915_private_t *dev_priv = dev->dev_private;
 	struct drm_mm_node *free_space;
 	gfp_t gfpmask = __GFP_NORETRY | __GFP_NOWARN;
-	u32 size, fence_size, fence_alignment, unfenced_alignment;
+	u32 size, fence_size, fence_alignment;
+	u32 unfenced_size, unfenced_alignment;
 	bool mappable, fenceable;
 	int ret;
 
@@ -2755,6 +2785,7 @@  i915_gem_object_bind_to_gtt(struct drm_i915_gem_object *obj,
 
 	fence_size = i915_gem_get_gtt_size(obj);
 	fence_alignment = i915_gem_get_gtt_alignment(obj);
+	unfenced_size = i915_gem_get_unfenced_gtt_size(obj);
 	unfenced_alignment = i915_gem_get_unfenced_gtt_alignment(obj);
 
 	if (alignment == 0)
@@ -2765,12 +2796,12 @@  i915_gem_object_bind_to_gtt(struct drm_i915_gem_object *obj,
 		return -EINVAL;
 	}
 
-	size = map_and_fenceable ? fence_size : obj->base.size;
+	size = map_and_fenceable ? fence_size : unfenced_size;
 
 	/* If the object is bigger than the entire aperture, reject it early
 	 * before evicting everything in a vain attempt to find space.
 	 */
-	if (obj->base.size >
+	if (size >
 	    (map_and_fenceable ? dev_priv->mm.gtt_mappable_end : dev_priv->mm.gtt_total)) {
 		DRM_ERROR("Attempting to bind an object larger than the aperture\n");
 		return -E2BIG;
diff --git a/drivers/gpu/drm/i915/i915_gem_tiling.c b/drivers/gpu/drm/i915/i915_gem_tiling.c
index 281ad3d..e4d5c58 100644
--- a/drivers/gpu/drm/i915/i915_gem_tiling.c
+++ b/drivers/gpu/drm/i915/i915_gem_tiling.c
@@ -349,7 +349,10 @@  i915_gem_set_tiling(struct drm_device *dev, void *data,
 		if (!obj->map_and_fenceable) {
 			u32 unfenced_alignment =
 				i915_gem_get_unfenced_gtt_alignment(obj);
-			if (obj->gtt_offset & (unfenced_alignment - 1))
+			u32 unfenced_size =
+				i915_gem_get_unfenced_gtt_size(obj);
+			if (obj->gtt_space->size < unfenced_size ||
+			    obj->gtt_offset & (unfenced_alignment - 1))
 				ret = i915_gem_object_unbind(obj);
 		}