drm/nouveau: add dumb ioctl support

Signed-off-by: Ben Skeggs <bskeggs@redhat.com>
diff --git a/drivers/gpu/drm/nouveau/nouveau_display.c b/drivers/gpu/drm/nouveau/nouveau_display.c
index ddbabef..b12fd2c 100644
--- a/drivers/gpu/drm/nouveau/nouveau_display.c
+++ b/drivers/gpu/drm/nouveau/nouveau_display.c
@@ -369,3 +369,48 @@
 	spin_unlock_irqrestore(&dev->event_lock, flags);
 	return 0;
 }
+
+int
+nouveau_display_dumb_create(struct drm_file *file_priv, struct drm_device *dev,
+			    struct drm_mode_create_dumb *args)
+{
+	struct nouveau_bo *bo;
+	int ret;
+
+	args->pitch = roundup(args->width * (args->bpp / 8), 256);
+	args->size = args->pitch * args->height;
+	args->size = roundup(args->size, PAGE_SIZE);
+
+	ret = nouveau_gem_new(dev, args->size, 0, TTM_PL_FLAG_VRAM, 0, 0, &bo);
+	if (ret)
+		return ret;
+
+	ret = drm_gem_handle_create(file_priv, bo->gem, &args->handle);
+	drm_gem_object_unreference_unlocked(bo->gem);
+	return ret;
+}
+
+int
+nouveau_display_dumb_destroy(struct drm_file *file_priv, struct drm_device *dev,
+			     uint32_t handle)
+{
+	return drm_gem_handle_delete(file_priv, handle);
+}
+
+int
+nouveau_display_dumb_map_offset(struct drm_file *file_priv,
+				struct drm_device *dev,
+				uint32_t handle, uint64_t *poffset)
+{
+	struct drm_gem_object *gem;
+
+	gem = drm_gem_object_lookup(dev, file_priv, handle);
+	if (gem) {
+		struct nouveau_bo *bo = gem->driver_private;
+		*poffset = bo->bo.addr_space_offset;
+		drm_gem_object_unreference_unlocked(gem);
+		return 0;
+	}
+
+	return -ENOENT;
+}