diff options
author | Manos Pitsidianakis <manos.pitsidianakis@linaro.org> | 2024-03-24 12:04:59 +0200 |
---|---|---|
committer | Michael S. Tsirkin <mst@redhat.com> | 2024-04-09 02:31:16 -0400 |
commit | 731655f87f319fd06f27282c6cafbc2467ac8045 (patch) | |
tree | 26379535218e48e114a997cb3175da3a6d7518fd /include | |
parent | a45f09935c88ae352a5ec120418a8b2b36ec1daa (diff) |
virtio-snd: rewrite invalid tx/rx message handling
The current handling of invalid virtqueue elements inside the TX/RX virt
queue handlers is wrong.
They are added in a per-stream invalid queue to be processed after the
handler is done examining each message, but the invalid message might
not be specifying any stream_id; which means it's invalid to add it to
any stream->invalid queue since stream could be NULL at this point.
This commit moves the invalid queue to the VirtIOSound struct which
guarantees there will always be a valid temporary place to store them
inside the tx/rx handlers. The queue will be emptied before the handler
returns, so the queue must be empty at any other point of the device's
lifetime.
Signed-off-by: Manos Pitsidianakis <manos.pitsidianakis@linaro.org>
Message-Id: <virtio-snd-rewrite-invalid-tx-rx-message-handling-v1.manos.pitsidianakis@linaro.org>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Diffstat (limited to 'include')
-rw-r--r-- | include/hw/audio/virtio-snd.h | 16 |
1 files changed, 15 insertions, 1 deletions
diff --git a/include/hw/audio/virtio-snd.h b/include/hw/audio/virtio-snd.h index 3d79181364..8dafedb276 100644 --- a/include/hw/audio/virtio-snd.h +++ b/include/hw/audio/virtio-snd.h @@ -151,7 +151,6 @@ struct VirtIOSoundPCMStream { QemuMutex queue_mutex; bool active; QSIMPLEQ_HEAD(, VirtIOSoundPCMBuffer) queue; - QSIMPLEQ_HEAD(, VirtIOSoundPCMBuffer) invalid; }; /* @@ -223,6 +222,21 @@ struct VirtIOSound { QemuMutex cmdq_mutex; QTAILQ_HEAD(, virtio_snd_ctrl_command) cmdq; bool processing_cmdq; + /* + * Convenience queue to keep track of invalid tx/rx queue messages inside + * the tx/rx callbacks. + * + * In the callbacks as a first step we are emptying the virtqueue to handle + * each message and we cannot add an invalid message back to the queue: we + * would re-process it in subsequent loop iterations. + * + * Instead, we add them to this queue and after finishing examining every + * virtqueue element, we inform the guest for each invalid message. + * + * This queue must be empty at all times except for inside the tx/rx + * callbacks. + */ + QSIMPLEQ_HEAD(, VirtIOSoundPCMBuffer) invalid; }; struct virtio_snd_ctrl_command { |