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@suse.de --- drivers/gpu/drm/mgag200/mgag200_main.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-)
diff --git a/drivers/gpu/drm/mgag200/mgag200_main.c b/drivers/gpu/drm/mgag200/mgag200_main.c index 780f983b0294..880047000ccf 100644 --- a/drivers/gpu/drm/mgag200/mgag200_main.c +++ b/drivers/gpu/drm/mgag200/mgag200_main.c @@ -33,7 +33,7 @@ int mgag200_framebuffer_init(struct drm_device *dev, struct drm_gem_object *obj) { int ret; - + drm_helper_mode_fill_fb_struct(dev, &gfb->base, mode_cmd); gfb->obj = obj; ret = drm_framebuffer_init(dev, &gfb->base, &mga_fb_funcs); @@ -333,7 +333,7 @@ static void mgag200_bo_unref(struct mgag200_bo **bo) return;
tbo = &((*bo)->bo); - ttm_bo_unref(&tbo); + ttm_bo_put(tbo); *bo = NULL; }