From: Hans Verkuil <hans.verkuil@xxxxxxxxx> Add media_request_object_find to find a request object inside a request based on ops and/or priv values. Objects of the same type (vb2 buffer, control handler) will have the same ops value. And objects that refer to the same 'parent' object (e.g. the v4l2_ctrl_handler that has the current driver state) will have the same priv value. The caller has to call media_request_object_put() for the returned object since this function increments the refcount. Signed-off-by: Hans Verkuil <hans.verkuil@xxxxxxxxx> Acked-by: Sakari Ailus <sakari.ailus@xxxxxxxxxxxxxxx> --- drivers/media/media-request.c | 25 +++++++++++++++++++++++++ include/media/media-request.h | 28 ++++++++++++++++++++++++++++ 2 files changed, 53 insertions(+) diff --git a/drivers/media/media-request.c b/drivers/media/media-request.c index b011f9911fbd..6b9a4fc0248b 100644 --- a/drivers/media/media-request.c +++ b/drivers/media/media-request.c @@ -342,6 +342,31 @@ static void media_request_object_release(struct kref *kref) obj->ops->release(obj); } +struct media_request_object * +media_request_object_find(struct media_request *req, + const struct media_request_object_ops *ops, + void *priv) +{ + struct media_request_object *obj; + struct media_request_object *found = NULL; + unsigned long flags; + + if (WARN_ON(!ops || !priv)) + return NULL; + + spin_lock_irqsave(&req->lock, flags); + list_for_each_entry(obj, &req->objects, list) { + if (obj->ops == ops && obj->priv == priv) { + media_request_object_get(obj); + found = obj; + break; + } + } + spin_unlock_irqrestore(&req->lock, flags); + return found; +} +EXPORT_SYMBOL_GPL(media_request_object_find); + void media_request_object_put(struct media_request_object *obj) { kref_put(&obj->kref, media_request_object_release); diff --git a/include/media/media-request.h b/include/media/media-request.h index d9931dddb3a8..2b458d4d8a65 100644 --- a/include/media/media-request.h +++ b/include/media/media-request.h @@ -252,6 +252,26 @@ static inline void media_request_object_get(struct media_request_object *obj) */ void media_request_object_put(struct media_request_object *obj); +/** + * media_request_object_find - Find an object in a request + * + * @req: The media request + * @ops: Find an object with this ops value + * @priv: Find an object with this priv value + * + * Both @ops and @priv must be non-NULL. + * + * Returns the object pointer or NULL if not found. The caller must + * call media_request_object_put() once it finished using the object. + * + * Since this function needs to walk the list of objects it takes + * the @req->lock spin lock to make this safe. + */ +struct media_request_object * +media_request_object_find(struct media_request *req, + const struct media_request_object_ops *ops, + void *priv); + /** * media_request_object_init - Initialise a media request object * @@ -323,6 +343,14 @@ static inline void media_request_object_put(struct media_request_object *obj) { } +static inline struct media_request_object * +media_request_object_find(struct media_request *req, + const struct media_request_object_ops *ops, + void *priv) +{ + return NULL; +} + static inline void media_request_object_init(struct media_request_object *obj) { obj->ops = NULL; -- 2.17.0