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

[cascardo/linux.git] / drivers / gpu / drm / nouveau / nouveau_display.c

diff --git a/drivers/gpu/drm/nouveau/nouveau_display.c b/drivers/gpu/drm/nouveau/nouveau_display.c
index a88e692..2640fcf 100644 (file)
--- a/drivers/gpu/drm/nouveau/nouveau_display.c
+++ b/drivers/gpu/drm/nouveau/nouveau_display.c
@@ -871,6 +871,7 @@ 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;
@@ -886,6 +887,14 @@ 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;