media: videobuf2-core: add request helper functions

Add a new helper function to tell if a request object is a buffer.

Add a new helper function that returns true if a media_request
contains at least one buffer.

Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com>
Reviewed-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>
Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>

drivers/media/common/videobuf2/videobuf2-core.c

@@ -1362,6 +1362,30 @@ static const struct media_request_object_ops vb2_core_req_ops = {
 	.release = vb2_req_release,
 };
 
+bool vb2_request_object_is_buffer(struct media_request_object *obj)
+{
+	return obj->ops == &vb2_core_req_ops;
+}
+EXPORT_SYMBOL_GPL(vb2_request_object_is_buffer);
+
+bool vb2_request_has_buffers(struct media_request *req)
+{
+	struct media_request_object *obj;
+	unsigned long flags;
+	bool has_buffers = false;
+
+	spin_lock_irqsave(&req->lock, flags);
+	list_for_each_entry(obj, &req->objects, list) {
+		if (vb2_request_object_is_buffer(obj)) {
+			has_buffers = true;
+			break;
+		}
+	}
+	spin_unlock_irqrestore(&req->lock, flags);
+	return has_buffers;
+}
+EXPORT_SYMBOL_GPL(vb2_request_has_buffers);
+
 int vb2_core_prepare_buf(struct vb2_queue *q, unsigned int index, void *pb)
 {
 	struct vb2_buffer *vb;