diff --git a/drivers/media/media-entity.c b/drivers/media/media-entity.c index cb30ffbd5ba8d534daec5ceab6d709d888844bcf..2c286c307145b6828a7ac8c3b4bfc4f05ae18735 100644 --- a/drivers/media/media-entity.c +++ b/drivers/media/media-entity.c @@ -20,6 +20,7 @@ * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA */ +#include #include #include #include @@ -121,7 +122,6 @@ static struct media_entity *stack_pop(struct media_entity_graph *graph) return entity; } -#define stack_peek(en) ((en)->stack[(en)->top - 1].entity) #define link_top(en) ((en)->stack[(en)->top].link) #define stack_top(en) ((en)->stack[(en)->top].entity) @@ -140,6 +140,12 @@ void media_entity_graph_walk_start(struct media_entity_graph *graph, { graph->top = 0; graph->stack[graph->top].entity = NULL; + bitmap_zero(graph->entities, MEDIA_ENTITY_ENUM_MAX_ID); + + if (WARN_ON(entity->id >= MEDIA_ENTITY_ENUM_MAX_ID)) + return; + + __set_bit(entity->id, graph->entities); stack_push(graph, entity); } EXPORT_SYMBOL_GPL(media_entity_graph_walk_start); @@ -180,9 +186,11 @@ media_entity_graph_walk_next(struct media_entity_graph *graph) /* Get the entity in the other end of the link . */ next = media_entity_other(entity, link); + if (WARN_ON(next->id >= MEDIA_ENTITY_ENUM_MAX_ID)) + return NULL; - /* Was it the entity we came here from? */ - if (next == stack_peek(graph)) { + /* Has the entity already been visited? */ + if (__test_and_set_bit(next->id, graph->entities)) { link_top(graph)++; continue; } diff --git a/include/media/media-entity.h b/include/media/media-entity.h index 06bacf937d61f2fc1ec4af25afe48e87410c38a2..10df55187981979be928ede57d2d2d0b903c03c4 100644 --- a/include/media/media-entity.h +++ b/include/media/media-entity.h @@ -23,6 +23,7 @@ #ifndef _MEDIA_ENTITY_H #define _MEDIA_ENTITY_H +#include #include #include @@ -113,12 +114,15 @@ static inline u32 media_entity_subtype(struct media_entity *entity) } #define MEDIA_ENTITY_ENUM_MAX_DEPTH 16 +#define MEDIA_ENTITY_ENUM_MAX_ID 64 struct media_entity_graph { struct { struct media_entity *entity; int link; } stack[MEDIA_ENTITY_ENUM_MAX_DEPTH]; + + DECLARE_BITMAP(entities, MEDIA_ENTITY_ENUM_MAX_ID); int top; };