@@ -263,6 +263,10 @@ struct vb2_buffer {
* after the 'buf_finish' op is called.
* copied_timestamp: the timestamp of this capture buffer was copied
* from an output buffer.
+ * need_cache_sync_on_prepare: do not sync/invalidate cache from
+ * buffer's ->prepare() callback.
+ * need_cache_sync_on_finish: do not sync/invalidate cache from buffer's
+ * ->finish() callback.
* queued_entry: entry on the queued buffers list, which holds
* all buffers queued from userspace
* done_entry: entry on the list that stores all buffers ready
@@ -273,6 +277,8 @@ struct vb2_buffer {
unsigned int synced:1;
unsigned int prepared:1;
unsigned int copied_timestamp:1;
+ unsigned int need_cache_sync_on_prepare:1;
+ unsigned int need_cache_sync_on_finish:1;
struct vb2_plane planes[VB2_MAX_PLANES];
struct list_head queued_entry;
@@ -491,6 +497,9 @@ struct vb2_buf_ops {
* @uses_requests: requests are used for this queue. Set to 1 the first time
* a request is queued. Set to 0 when the queue is canceled.
* If this is 1, then you cannot queue buffers directly.
+ * @allow_cache_hints: when set user-space can pass cache management hints in
+ * order to skip cache flush/invalidation on ->prepare() or/and
+ * ->finish().
* @lock: pointer to a mutex that protects the &struct vb2_queue. The
* driver can set this to a mutex to let the v4l2 core serialize
* the queuing ioctls. If the driver wants to handle locking
@@ -564,6 +573,7 @@ struct vb2_queue {
unsigned requires_requests:1;
unsigned uses_qbuf:1;
unsigned uses_requests:1;
+ unsigned allow_cache_hints:1;
struct mutex *lock;
void *owner;
Extend vb2_buffer and vb2_queue structs with cache management members. V4L2 UAPI already contains two buffer flags which user-space, supposedly, can use to control buffer cache sync: - V4L2_BUF_FLAG_NO_CACHE_INVALIDATE - V4L2_BUF_FLAG_NO_CACHE_CLEAN None of these, however, do anything at the moment. This patch set is intended to change it. Since user-space cache management hints are supposed to be implemented on a per-buffer basis we need to extend vb2_buffer struct with two new memebers ->need_cache_sync_on_prepare and ->need_cache_sync_on_finish, which will store corresponding user-space hints. In order to preserve the existing behaviour, user-space cache managements flags will be handled only by those drivers that permit user-space cache hints. That's the purpose of vb2_queue ->allow_cache_hints member. Driver must set ->allow_cache_hints during queue initialisation to enable cache management hints mechanism. Only drivers that set ->allow_cache_hints during queue initialisation will handle user-space cache management hints. Otherwise hints will be ignored. Signed-off-by: Sergey Senozhatsky <senozhatsky@chromium.org> --- include/media/videobuf2-core.h | 10 ++++++++++ 1 file changed, 10 insertions(+)