drm/v3d: replace obj lookup steps with drm_gem_objects_lookup

As v3d_lookup_bos() performs the same steps as drm_gem_objects_lookup(),
replace the explicit code in v3d to simply use the DRM function.
Signed-off-by: Melissa Wen <mwen@igalia.com>
Reviewed-by: Maíra Canal <mcanal@igalia.com>
Signed-off-by: Melissa Wen <melissa.srw@gmail.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20221205135538.3545051-3-mwen@igalia.com

drivers/gpu/drm/v3d/v3d_gem.c

@@ -299,10 +299,6 @@ v3d_lookup_bos(struct drm_device *dev,
 	       u64 bo_handles,
 	       u32 bo_count)
 {
-	u32 *handles;
-	int ret = 0;
-	int i;
-
 	job->bo_count = bo_count;
 
 	if (!job->bo_count) {
@@ -313,48 +309,9 @@ v3d_lookup_bos(struct drm_device *dev,
 		return -EINVAL;
 	}
 
-	job->bo = kvmalloc_array(job->bo_count,
-				 sizeof(struct drm_gem_dma_object *),
-				 GFP_KERNEL | __GFP_ZERO);
-	if (!job->bo) {
-		DRM_DEBUG("Failed to allocate validated BO pointers\n");
-		return -ENOMEM;
-	}
-
-	handles = kvmalloc_array(job->bo_count, sizeof(u32), GFP_KERNEL);
-	if (!handles) {
-		ret = -ENOMEM;
-		DRM_DEBUG("Failed to allocate incoming GEM handles\n");
-		goto fail;
-	}
-
-	if (copy_from_user(handles,
-			   (void __user *)(uintptr_t)bo_handles,
-			   job->bo_count * sizeof(u32))) {
-		ret = -EFAULT;
-		DRM_DEBUG("Failed to copy in GEM handles\n");
-		goto fail;
-	}
-
-	spin_lock(&file_priv->table_lock);
-	for (i = 0; i < job->bo_count; i++) {
-		struct drm_gem_object *bo = idr_find(&file_priv->object_idr,
-						     handles[i]);
-		if (!bo) {
-			DRM_DEBUG("Failed to look up GEM BO %d: %d\n",
-				  i, handles[i]);
-			ret = -ENOENT;
-			spin_unlock(&file_priv->table_lock);
-			goto fail;
-		}
-		drm_gem_object_get(bo);
-		job->bo[i] = bo;
-	}
-	spin_unlock(&file_priv->table_lock);
-
-fail:
-	kvfree(handles);
-	return ret;
+	return drm_gem_objects_lookup(file_priv,
+				      (void __user *)(uintptr_t)bo_handles,
+				      job->bo_count, &job->bo);
 }
 
 static void