[media_stage/next] media: videobuf2-core: update vb2_thread if wait_finish/prepare are NULL

[media-ci]

On Thu Oct 17 17:09:23 2024 +0200, Hans Verkuil wrote:
> The vb2_thread is used for DVB support. This will queue and dequeue buffers
> automatically.
> 
> It calls wait_finish/prepare around vb2_core_dqbuf() and vb2_core_qbuf(),
> but that assumes all drivers have these ops set. But that will change
> due to commit 88785982a19d ("media: vb2: use lock if wait_prepare/finish
> are NULL").
> 
> So instead just check if the callback is available, and if not, use
> q->lock, just as __vb2_wait_for_done_vb() does.
> 
> Signed-off-by: Hans Verkuil <hverk...@xs4all.nl>
> Reviewed-by: Mauro Carvalho Chehab <mchehab+hua...@kernel.org>

Patch committed.

Thanks,
Hans Verkuil

 drivers/media/common/videobuf2/videobuf2-core.c | 26 +++++++++++++++++++------
 1 file changed, 20 insertions(+), 6 deletions(-)

---

diff --git a/drivers/media/common/videobuf2/videobuf2-core.c 
b/drivers/media/common/videobuf2/videobuf2-core.c
index d064e0664851..d2275c878ea9 100644
--- a/drivers/media/common/videobuf2/videobuf2-core.c
+++ b/drivers/media/common/videobuf2/videobuf2-core.c
@@ -3218,10 +3218,17 @@ static int vb2_thread(void *data)
                                continue;
                        prequeue--;
                } else {
-                       call_void_qop(q, wait_finish, q);
-                       if (!threadio->stop)
+                       if (!threadio->stop) {
+                               if (q->ops->wait_finish)
+                                       call_void_qop(q, wait_finish, q);
+                               else if (q->lock)
+                                       mutex_lock(q->lock);
                                ret = vb2_core_dqbuf(q, &index, NULL, 0);
-                       call_void_qop(q, wait_prepare, q);
+                               if (q->ops->wait_prepare)
+                                       call_void_qop(q, wait_prepare, q);
+                               else if (q->lock)
+                                       mutex_unlock(q->lock);
+                       }
                        dprintk(q, 5, "file io: vb2_dqbuf result: %d\n", ret);
                        if (!ret)
                                vb = vb2_get_buffer(q, index);
@@ -3233,12 +3240,19 @@ static int vb2_thread(void *data)
                if (vb->state != VB2_BUF_STATE_ERROR)
                        if (threadio->fnc(vb, threadio->priv))
                                break;
-               call_void_qop(q, wait_finish, q);
                if (copy_timestamp)
                        vb->timestamp = ktime_get_ns();
-               if (!threadio->stop)
+               if (!threadio->stop) {
+                       if (q->ops->wait_finish)
+                               call_void_qop(q, wait_finish, q);
+                       else if (q->lock)
+                               mutex_lock(q->lock);
                        ret = vb2_core_qbuf(q, vb, NULL, NULL);
-               call_void_qop(q, wait_prepare, q);
+                       if (q->ops->wait_prepare)
+                               call_void_qop(q, wait_prepare, q);
+                       else if (q->lock)
+                               mutex_unlock(q->lock);
+               }
                if (ret || threadio->stop)
                        break;
        }