diff --git a/drivers/gpu/drm/drm_exec.c b/drivers/gpu/drm/drm_exec.c index ff69cf0fb42aab..5d2809de4517ca 100644 --- a/drivers/gpu/drm/drm_exec.c +++ b/drivers/gpu/drm/drm_exec.c @@ -56,7 +56,7 @@ static void drm_exec_unlock_all(struct drm_exec *exec) struct drm_gem_object *obj; unsigned long index; - drm_exec_for_each_locked_object(exec, index, obj) { + drm_exec_for_each_locked_object_reverse(exec, index, obj) { dma_resv_unlock(obj->resv); drm_gem_object_put(obj); } diff --git a/include/drm/drm_exec.h b/include/drm/drm_exec.h index e0462361adf9ed..55764cf7c3743f 100644 --- a/include/drm/drm_exec.h +++ b/include/drm/drm_exec.h @@ -51,6 +51,20 @@ struct drm_exec { struct drm_gem_object *prelocked; }; +/** + * drm_exec_obj() - Return the object for a give drm_exec index + * @exec: Pointer to the drm_exec context + * @index: The index. + * + * Return: Pointer to the locked object corresponding to @index if + * index is within the number of locked objects. NULL otherwise. + */ +static inline struct drm_gem_object * +drm_exec_obj(struct drm_exec *exec, unsigned long index) +{ + return index < exec->num_objects ? exec->objects[index] : NULL; +} + /** * drm_exec_for_each_locked_object - iterate over all the locked objects * @exec: drm_exec object @@ -59,10 +73,23 @@ struct drm_exec { * * Iterate over all the locked GEM objects inside the drm_exec object. */ -#define drm_exec_for_each_locked_object(exec, index, obj) \ - for (index = 0, obj = (exec)->objects[0]; \ - index < (exec)->num_objects; \ - ++index, obj = (exec)->objects[index]) +#define drm_exec_for_each_locked_object(exec, index, obj) \ + for ((index) = 0; ((obj) = drm_exec_obj(exec, index)); ++(index)) + +/** + * drm_exec_for_each_locked_object_reverse - iterate over all the locked + * objects in reverse locking order + * @exec: drm_exec object + * @index: unsigned long index for the iteration + * @obj: the current GEM object + * + * Iterate over all the locked GEM objects inside the drm_exec object in + * reverse locking order. Note that @index may go below zero and wrap, + * but that will be caught by drm_exec_object(), returning a NULL object. + */ +#define drm_exec_for_each_locked_object_reverse(exec, index, obj) \ + for ((index) = (exec)->num_objects - 1; \ + ((obj) = drm_exec_obj(exec, index)); --(index)) /** * drm_exec_until_all_locked - loop until all GEM objects are locked