Revert "drm/gem: Warn on illegal use of the dumb buffer interface v2"

This reverts commit 355a70183848f21198e9f6296bd646df3478a26d.

This had some bad side effects under normal operation, and should
have been dropped earlier.

Signed-off-by: Dave Airlie <airlied@redhat.com>
diff --git a/drivers/gpu/drm/i915/i915_gem.c b/drivers/gpu/drm/i915/i915_gem.c
index 4a9faea6..52adcb6 100644
--- a/drivers/gpu/drm/i915/i915_gem.c
+++ b/drivers/gpu/drm/i915/i915_gem.c
@@ -401,7 +401,6 @@
 i915_gem_create(struct drm_file *file,
 		struct drm_device *dev,
 		uint64_t size,
-		bool dumb,
 		uint32_t *handle_p)
 {
 	struct drm_i915_gem_object *obj;
@@ -417,7 +416,6 @@
 	if (obj == NULL)
 		return -ENOMEM;
 
-	obj->base.dumb = dumb;
 	ret = drm_gem_handle_create(file, &obj->base, &handle);
 	/* drop reference from allocate - handle holds it now */
 	drm_gem_object_unreference_unlocked(&obj->base);
@@ -437,7 +435,7 @@
 	args->pitch = ALIGN(args->width * DIV_ROUND_UP(args->bpp, 8), 64);
 	args->size = args->pitch * args->height;
 	return i915_gem_create(file, dev,
-			       args->size, true, &args->handle);
+			       args->size, &args->handle);
 }
 
 /**
@@ -450,7 +448,7 @@
 	struct drm_i915_gem_create *args = data;
 
 	return i915_gem_create(file, dev,
-			       args->size, false, &args->handle);
+			       args->size, &args->handle);
 }
 
 static inline int
@@ -1840,10 +1838,10 @@
 	drm_gem_free_mmap_offset(&obj->base);
 }
 
-static int
+int
 i915_gem_mmap_gtt(struct drm_file *file,
 		  struct drm_device *dev,
-		  uint32_t handle, bool dumb,
+		  uint32_t handle,
 		  uint64_t *offset)
 {
 	struct drm_i915_private *dev_priv = dev->dev_private;
@@ -1860,13 +1858,6 @@
 		goto unlock;
 	}
 
-	/*
-	 * We don't allow dumb mmaps on objects created using another
-	 * interface.
-	 */
-	WARN_ONCE(dumb && !(obj->base.dumb || obj->base.import_attach),
-		  "Illegal dumb map of accelerated buffer.\n");
-
 	if (obj->base.size > dev_priv->gtt.mappable_end) {
 		ret = -E2BIG;
 		goto out;
@@ -1891,15 +1882,6 @@
 	return ret;
 }
 
-int
-i915_gem_dumb_map_offset(struct drm_file *file,
-			 struct drm_device *dev,
-			 uint32_t handle,
-			 uint64_t *offset)
-{
-	return i915_gem_mmap_gtt(file, dev, handle, true, offset);
-}
-
 /**
  * i915_gem_mmap_gtt_ioctl - prepare an object for GTT mmap'ing
  * @dev: DRM device
@@ -1921,7 +1903,7 @@
 {
 	struct drm_i915_gem_mmap_gtt *args = data;
 
-	return i915_gem_mmap_gtt(file, dev, args->handle, false, &args->offset);
+	return i915_gem_mmap_gtt(file, dev, args->handle, &args->offset);
 }
 
 static inline int