[PATCH] staging/vboxvideo: Replace ttm_bo_unref with ttm_bo_put

Thomas Zimmermann tzimmermann at suse.de
Mon Sep 10 09:36:44 UTC 2018

The function ttm_bo_put releases a reference to a TTM buffer object. The
function's name is more aligned to the Linux kernel convention of naming
ref-counting function _get and _put.

A call to ttm_bo_unref takes the address of the TTM BO object's pointer and
clears the pointer's value to NULL. This is not necessary in most cases and
sometimes even worked around by the calling code. A call to ttm_bo_put only
releases the reference without clearing the pointer.

The current behaviour of cleaning the pointer is kept in the calling code,
but should be removed if not required in a later patch.

Signed-off-by: Thomas Zimmermann <tzimmermann at suse.de>
 drivers/staging/vboxvideo/vbox_main.c | 5 ++---
 1 file changed, 2 insertions(+), 3 deletions(-)

diff --git a/drivers/staging/vboxvideo/vbox_main.c b/drivers/staging/vboxvideo/vbox_main.c
index 429f6a453619..b6cff31903b3 100644
--- a/drivers/staging/vboxvideo/vbox_main.c
+++ b/drivers/staging/vboxvideo/vbox_main.c
@@ -490,9 +490,8 @@ static void vbox_bo_unref(struct vbox_bo **bo)
 	tbo = &((*bo)->bo);
-	ttm_bo_unref(&tbo);
-	if (!tbo)
-		*bo = NULL;
+	ttm_bo_put(tbo);
+	*bo = NULL;
 void vbox_gem_free_object(struct drm_gem_object *obj)

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