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

This reverts commit 355a7018.

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

drivers/gpu/drm/i915/i915_drv.c

@@ -1586,7 +1586,7 @@ static struct drm_driver driver = {
 	.gem_prime_import = i915_gem_prime_import,
 
 	.dumb_create = i915_gem_dumb_create,
-	.dumb_map_offset = i915_gem_dumb_map_offset,
+	.dumb_map_offset = i915_gem_mmap_gtt,
 	.dumb_destroy = drm_gem_dumb_destroy,
 	.ioctls = i915_ioctls,
 	.fops = &i915_driver_fops,

drivers/gpu/drm/i915/i915_drv.h

@@ -2501,9 +2501,8 @@ void i915_vma_move_to_active(struct i915_vma *vma,
 int i915_gem_dumb_create(struct drm_file *file_priv,
 			 struct drm_device *dev,
 			 struct drm_mode_create_dumb *args);
-int i915_gem_dumb_map_offset(struct drm_file *file_priv,
-			     struct drm_device *dev, uint32_t handle,
-			     uint64_t *offset);
+int i915_gem_mmap_gtt(struct drm_file *file_priv, struct drm_device *dev,
+		      uint32_t handle, uint64_t *offset);
 /**
  * Returns true if seq1 is later than seq2.
  */

drivers/gpu/drm/i915/i915_gem.c

@@ -401,7 +401,6 @@ static int
 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 @@ i915_gem_create(struct drm_file *file,
 	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 @@ i915_gem_dumb_create(struct drm_file *file,
 	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 @@ i915_gem_create_ioctl(struct drm_device *dev, void *data,
 	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 @@ static void i915_gem_object_free_mmap_offset(struct drm_i915_gem_object *obj)
 	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 @@ i915_gem_mmap_gtt(struct drm_file *file,
 		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 @@ i915_gem_mmap_gtt(struct drm_file *file,
 	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 @@ i915_gem_mmap_gtt_ioctl(struct drm_device *dev, void *data,
 {
 	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

drivers/gpu/drm/i915/i915_gem_execbuffer.c

@@ -121,9 +121,6 @@ eb_lookup_vmas(struct eb_vmas *eb,
 			goto err;
 		}
 
-		WARN_ONCE(obj->base.dumb,
-			  "GPU use of dumb buffer is illegal.\n");
-
 		drm_gem_object_reference(&obj->base);
 		list_add_tail(&obj->obj_exec_link, &objects);
 	}

drivers/gpu/drm/nouveau/nouveau_display.c

@@ -876,7 +876,6 @@ nouveau_display_dumb_create(struct drm_file *file_priv, struct drm_device *dev,
 	if (ret)
 		return ret;
 
-	bo->gem.dumb = true;
 	ret = drm_gem_handle_create(file_priv, &bo->gem, &args->handle);
 	drm_gem_object_unreference_unlocked(&bo->gem);
 	return ret;
@@ -892,14 +891,6 @@ nouveau_display_dumb_map_offset(struct drm_file *file_priv,
 	gem = drm_gem_object_lookup(dev, file_priv, handle);
 	if (gem) {
 		struct nouveau_bo *bo = nouveau_gem_object(gem);
-
-		/*
-		 * We don't allow dumb mmaps on objects created using another
-		 * interface.
-		 */
-		WARN_ONCE(!(gem->dumb || gem->import_attach),
-			  "Illegal dumb map of accelerated buffer.\n");
-
 		*poffset = drm_vma_node_offset_addr(&bo->bo.vma_node);
 		drm_gem_object_unreference_unlocked(gem);
 		return 0;

drivers/gpu/drm/nouveau/nouveau_gem.c

@@ -444,9 +444,6 @@ validate_list(struct nouveau_channel *chan, struct nouveau_cli *cli,
 	list_for_each_entry(nvbo, list, entry) {
 		struct drm_nouveau_gem_pushbuf_bo *b = &pbbo[nvbo->pbbo_index];
 
-		WARN_ONCE(nvbo->gem.dumb,
-			  "GPU use of dumb buffer is illegal.\n");
-
 		ret = nouveau_gem_set_domain(&nvbo->gem, b->read_domains,
 					     b->write_domains,
 					     b->valid_domains);

drivers/gpu/drm/radeon/radeon_gem.c

@@ -394,10 +394,9 @@ int radeon_gem_set_domain_ioctl(struct drm_device *dev, void *data,
 	return r;
 }
 
-static int radeon_mode_mmap(struct drm_file *filp,
-			    struct drm_device *dev,
-			    uint32_t handle, bool dumb,
-			    uint64_t *offset_p)
+int radeon_mode_dumb_mmap(struct drm_file *filp,
+			  struct drm_device *dev,
+			  uint32_t handle, uint64_t *offset_p)
 {
 	struct drm_gem_object *gobj;
 	struct radeon_bo *robj;
@@ -406,14 +405,6 @@ static int radeon_mode_mmap(struct drm_file *filp,
 	if (gobj == NULL) {
 		return -ENOENT;
 	}
-
-	/*
-	 * We don't allow dumb mmaps on objects created using another
-	 * interface.
-	 */
-	WARN_ONCE(dumb && !(gobj->dumb || gobj->import_attach),
-		"Illegal dumb map of GPU buffer.\n");
-
 	robj = gem_to_radeon_bo(gobj);
 	if (radeon_ttm_tt_has_userptr(robj->tbo.ttm)) {
 		drm_gem_object_unreference_unlocked(gobj);
@@ -424,20 +415,12 @@ static int radeon_mode_mmap(struct drm_file *filp,
 	return 0;
 }
 
-int radeon_mode_dumb_mmap(struct drm_file *filp,
-			  struct drm_device *dev,
-			  uint32_t handle, uint64_t *offset_p)
-{
-	return radeon_mode_mmap(filp, dev, handle, true, offset_p);
-}
-
 int radeon_gem_mmap_ioctl(struct drm_device *dev, void *data,
 			  struct drm_file *filp)
 {
 	struct drm_radeon_gem_mmap *args = data;
 
-	return radeon_mode_mmap(filp, dev, args->handle, false,
-				&args->addr_ptr);
+	return radeon_mode_dumb_mmap(filp, dev, args->handle, &args->addr_ptr);
 }
 
 int radeon_gem_busy_ioctl(struct drm_device *dev, void *data,
@@ -763,7 +746,6 @@ int radeon_mode_dumb_create(struct drm_file *file_priv,
 		return -ENOMEM;
 
 	r = drm_gem_handle_create(file_priv, gobj, &handle);
-	gobj->dumb = true;
 	/* drop reference from allocate - handle holds it now */
 	drm_gem_object_unreference_unlocked(gobj);
 	if (r) {

drivers/gpu/drm/radeon/radeon_object.c

@@ -529,9 +529,6 @@ int radeon_bo_list_validate(struct radeon_device *rdev,
 			u32 current_domain =
 				radeon_mem_type_to_domain(bo->tbo.mem.mem_type);
 
-			WARN_ONCE(bo->gem_base.dumb,
-				  "GPU use of dumb buffer is illegal.\n");
-
 			/* Check if this buffer will be moved and don't move it
 			 * if we have moved too many buffers for this IB already.
 			 *

include/drm/drm_gem.h

@@ -119,13 +119,6 @@ struct drm_gem_object {
 	 * simply leave it as NULL.
 	 */
 	struct dma_buf_attachment *import_attach;
-
-	/**
-	 * dumb - created as dumb buffer
-	 * Whether the gem object was created using the dumb buffer interface
-	 * as such it may not be used for GPU rendering.
-	 */
-	bool dumb;
 };
 
 void drm_gem_object_release(struct drm_gem_object *obj);