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virtio-sound: implement audio capture (RX)
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To perform audio capture we duplicate the TX logic of the previous
commit with the following difference: we receive data from the QEMU
audio backend and write it in the virt queue IO buffers the guest sends
to QEMU. When they are full (i.e. they have `period_bytes` amount of
data) or when recording stops in QEMU's audio backend, the buffer is
returned to the guest by notifying it.

Signed-off-by: Manos Pitsidianakis <manos.pitsidianakis@linaro.org>
Tested-by: Alex Bennée <alex.bennee@linaro.org>
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Message-Id: <e56a17741a24ccadfbbea19d3c60c9406b795b23.1698062525.git.manos.pitsidianakis@linaro.org>
Acked-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
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@epilys @mstsirkin
epilys authored and mstsirkin committed Nov 7, 2023
1 parent 18a7528 commit d8d64ac
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Showing 2 changed files with 230 additions and 35 deletions.
3 changes: 2 additions & 1 deletion hw/audio/trace-events
View file
Original file line number Diff line number Diff line change
Expand Up @@ -56,4 +56,5 @@ virtio_snd_handle_code(uint32_t val, const char *code) "ctrl code msg val = %"PR
virtio_snd_handle_chmap_info(void) "VIRTIO_SND_CHMAP_INFO called"
virtio_snd_handle_event(void) "event queue callback called"
virtio_snd_pcm_stream_flush(uint32_t stream) "flushing stream %"PRIu32
virtio_snd_handle_xfer(void) "tx/rx queue callback called"
virtio_snd_handle_tx_xfer(void) "tx queue callback called"
virtio_snd_handle_rx_xfer(void) "rx queue callback called"
262 changes: 228 additions & 34 deletions hw/audio/virtio-snd.c
View file
Original file line number Diff line number Diff line change
Expand Up @@ -28,13 +28,14 @@

#define VIRTIO_SOUND_VM_VERSION 1
#define VIRTIO_SOUND_JACK_DEFAULT 0
#define VIRTIO_SOUND_STREAM_DEFAULT 1
#define VIRTIO_SOUND_STREAM_DEFAULT 2
#define VIRTIO_SOUND_CHMAP_DEFAULT 0
#define VIRTIO_SOUND_HDA_FN_NID 0

static void virtio_snd_pcm_out_cb(void *data, int available);
static void virtio_snd_process_cmdq(VirtIOSound *s);
static void virtio_snd_pcm_flush(VirtIOSoundPCMStream *stream);
static void virtio_snd_pcm_in_cb(void *data, int available);

static uint32_t supported_formats = BIT(VIRTIO_SND_PCM_FMT_S8)
| BIT(VIRTIO_SND_PCM_FMT_U8)
Expand Down Expand Up @@ -408,10 +409,13 @@ static void virtio_snd_get_qemu_audsettings(audsettings *as,
static void virtio_snd_pcm_close(VirtIOSoundPCMStream *stream)
{
if (stream) {
virtio_snd_pcm_flush(stream);
if (stream->info.direction == VIRTIO_SND_D_OUTPUT) {
virtio_snd_pcm_flush(stream);
AUD_close_out(&stream->pcm->snd->card, stream->voice.out);
stream->voice.out = NULL;
} else if (stream->info.direction == VIRTIO_SND_D_INPUT) {
AUD_close_in(&stream->pcm->snd->card, stream->voice.in);
stream->voice.in = NULL;
}
}
}
Expand Down Expand Up @@ -482,7 +486,13 @@ static uint32_t virtio_snd_pcm_prepare(VirtIOSound *s, uint32_t stream_id)
&as);
AUD_set_volume_out(stream->voice.out, 0, 255, 255);
} else {
qemu_log_mask(LOG_UNIMP, "virtio_snd: input/capture is unimplemented.");
stream->voice.in = AUD_open_in(&s->card,
stream->voice.in,
"virtio-sound.in",
stream,
virtio_snd_pcm_in_cb,
&as);
AUD_set_volume_in(stream->voice.in, 0, 255, 255);
}

return cpu_to_le32(VIRTIO_SND_S_OK);
Expand Down Expand Up @@ -573,6 +583,8 @@ static void virtio_snd_handle_pcm_start_stop(VirtIOSound *s,
}
if (stream->info.direction == VIRTIO_SND_D_OUTPUT) {
AUD_set_active_out(stream->voice.out, start);
} else {
AUD_set_active_in(stream->voice.in, start);
}
} else {
error_report("Invalid stream id: %"PRIu32, stream_id);
Expand Down Expand Up @@ -814,22 +826,64 @@ static void virtio_snd_handle_event(VirtIODevice *vdev, VirtQueue *vq)
trace_virtio_snd_handle_event();
}

static inline void empty_invalid_queue(VirtIODevice *vdev, VirtQueue *vq)
{
VirtIOSoundPCMBuffer *buffer = NULL;
VirtIOSoundPCMStream *stream = NULL;
virtio_snd_pcm_status resp = { 0 };
VirtIOSound *vsnd = VIRTIO_SND(vdev);
bool any = false;

for (uint32_t i = 0; i < vsnd->snd_conf.streams; i++) {
stream = vsnd->pcm->streams[i];
if (stream) {
any = false;
WITH_QEMU_LOCK_GUARD(&stream->queue_mutex) {
while (!QSIMPLEQ_EMPTY(&stream->invalid)) {
buffer = QSIMPLEQ_FIRST(&stream->invalid);
if (buffer->vq != vq) {
break;
}
any = true;
resp.status = cpu_to_le32(VIRTIO_SND_S_BAD_MSG);
iov_from_buf(buffer->elem->in_sg,
buffer->elem->in_num,
0,
&resp,
sizeof(virtio_snd_pcm_status));
virtqueue_push(vq,
buffer->elem,
sizeof(virtio_snd_pcm_status));
QSIMPLEQ_REMOVE_HEAD(&stream->invalid, entry);
virtio_snd_pcm_buffer_free(buffer);
}
if (any) {
/*
* Notify vq about virtio_snd_pcm_status responses.
* Buffer responses must be notified separately later.
*/
virtio_notify(vdev, vq);
}
}
}
}
}

/*
* The tx virtqueue handler. Makes the buffers available to their respective
* streams for consumption.
*
* @vdev: VirtIOSound device
* @vq: tx virtqueue
*/
static void virtio_snd_handle_tx(VirtIODevice *vdev, VirtQueue *vq)
static void virtio_snd_handle_tx_xfer(VirtIODevice *vdev, VirtQueue *vq)
{
VirtIOSound *s = VIRTIO_SND(vdev);
VirtIOSoundPCMStream *stream = NULL;
VirtIOSoundPCMBuffer *buffer;
VirtQueueElement *elem;
size_t msg_sz, size;
virtio_snd_pcm_xfer hdr;
virtio_snd_pcm_status resp = { 0 };
uint32_t stream_id;
/*
* If any of the I/O messages are invalid, put them in stream->invalid and
Expand All @@ -840,7 +894,7 @@ static void virtio_snd_handle_tx(VirtIODevice *vdev, VirtQueue *vq)
if (!virtio_queue_ready(vq)) {
return;
}
trace_virtio_snd_handle_xfer();
trace_virtio_snd_handle_tx_xfer();

for (;;) {
elem = virtqueue_pop(vq, sizeof(VirtQueueElement));
Expand Down Expand Up @@ -893,36 +947,88 @@ static void virtio_snd_handle_tx(VirtIODevice *vdev, VirtQueue *vq)
}

if (must_empty_invalid_queue) {
WITH_QEMU_LOCK_GUARD(&stream->queue_mutex) {
while (!QSIMPLEQ_EMPTY(&stream->invalid)) {
buffer = QSIMPLEQ_FIRST(&stream->invalid);

resp.status = cpu_to_le32(VIRTIO_SND_S_BAD_MSG);
iov_from_buf(buffer->elem->in_sg,
buffer->elem->in_num,
0,
&resp,
sizeof(virtio_snd_pcm_status));
virtqueue_push(vq, buffer->elem, sizeof(virtio_snd_pcm_status));
QSIMPLEQ_REMOVE_HEAD(&stream->invalid, entry);
virtio_snd_pcm_buffer_free(buffer);
}
/*
* Notify vq about virtio_snd_pcm_status responses.
* Buffer responses must be notified separately later.
*/
virtio_notify(vdev, vq);
}
empty_invalid_queue(vdev, vq);
}
}

/*
* Stub buffer virtqueue handler.
* The rx virtqueue handler. Makes the buffers available to their respective
* streams for consumption.
*
* @vdev: VirtIOSound device
* @vq: virtqueue
* @vq: rx virtqueue
*/
static void virtio_snd_handle_xfer(VirtIODevice *vdev, VirtQueue *vq) {}
static void virtio_snd_handle_rx_xfer(VirtIODevice *vdev, VirtQueue *vq)
{
VirtIOSound *s = VIRTIO_SND(vdev);
VirtIOSoundPCMStream *stream = NULL;
VirtIOSoundPCMBuffer *buffer;
VirtQueueElement *elem;
size_t msg_sz, size;
virtio_snd_pcm_xfer hdr;
uint32_t stream_id;
/*
* if any of the I/O messages are invalid, put them in stream->invalid and
* return them after the for loop.
*/
bool must_empty_invalid_queue = false;

if (!virtio_queue_ready(vq)) {
return;
}
trace_virtio_snd_handle_rx_xfer();

for (;;) {
elem = virtqueue_pop(vq, sizeof(VirtQueueElement));
if (!elem) {
break;
}
/* get the message hdr object */
msg_sz = iov_to_buf(elem->out_sg,
elem->out_num,
0,
&hdr,
sizeof(virtio_snd_pcm_xfer));
if (msg_sz != sizeof(virtio_snd_pcm_xfer)) {
goto rx_err;
}
stream_id = le32_to_cpu(hdr.stream_id);

if (stream_id >= s->snd_conf.streams
|| !s->pcm->streams[stream_id]) {
goto rx_err;
}

stream = s->pcm->streams[stream_id];
if (stream == NULL || stream->info.direction != VIRTIO_SND_D_INPUT) {
goto rx_err;
}
WITH_QEMU_LOCK_GUARD(&stream->queue_mutex) {
size = iov_size(elem->in_sg, elem->in_num) -
sizeof(virtio_snd_pcm_status);
buffer = g_malloc0(sizeof(VirtIOSoundPCMBuffer) + size);
buffer->elem = elem;
buffer->vq = vq;
buffer->size = 0;
buffer->offset = 0;
QSIMPLEQ_INSERT_TAIL(&stream->queue, buffer, entry);
}
continue;

rx_err:
WITH_QEMU_LOCK_GUARD(&stream->queue_mutex) {
must_empty_invalid_queue = true;
buffer = g_malloc0(sizeof(VirtIOSoundPCMBuffer));
buffer->elem = elem;
buffer->vq = vq;
QSIMPLEQ_INSERT_TAIL(&stream->invalid, buffer, entry);
}
}

if (must_empty_invalid_queue) {
empty_invalid_queue(vdev, vq);
}
}

static uint64_t get_features(VirtIODevice *vdev, uint64_t features,
Error **errp)
Expand Down Expand Up @@ -1010,9 +1116,9 @@ static void virtio_snd_realize(DeviceState *dev, Error **errp)
vsnd->queues[VIRTIO_SND_VQ_EVENT] =
virtio_add_queue(vdev, 64, virtio_snd_handle_event);
vsnd->queues[VIRTIO_SND_VQ_TX] =
virtio_add_queue(vdev, 64, virtio_snd_handle_tx);
virtio_add_queue(vdev, 64, virtio_snd_handle_tx_xfer);
vsnd->queues[VIRTIO_SND_VQ_RX] =
virtio_add_queue(vdev, 64, virtio_snd_handle_xfer);
virtio_add_queue(vdev, 64, virtio_snd_handle_rx_xfer);
qemu_mutex_init(&vsnd->cmdq_mutex);
QTAILQ_INIT(&vsnd->cmdq);

Expand Down Expand Up @@ -1116,19 +1222,107 @@ static void virtio_snd_pcm_out_cb(void *data, int available)
}

/*
* Flush all buffer data from this stream's queue into the driver's virtual
* queue.
* Flush all buffer data from this input stream's queue into the driver's
* virtual queue.
*
* @stream: VirtIOSoundPCMStream *stream
*/
static inline void return_rx_buffer(VirtIOSoundPCMStream *stream,
VirtIOSoundPCMBuffer *buffer)
{
virtio_snd_pcm_status resp = { 0 };
resp.status = cpu_to_le32(VIRTIO_SND_S_OK);
resp.latency_bytes = 0;
/* Copy data -if any- to guest */
iov_from_buf(buffer->elem->in_sg,
buffer->elem->in_num,
0,
buffer->data,
buffer->size);
iov_from_buf(buffer->elem->in_sg,
buffer->elem->in_num,
buffer->size,
&resp,
sizeof(virtio_snd_pcm_status));
virtqueue_push(buffer->vq,
buffer->elem,
sizeof(virtio_snd_pcm_status) + buffer->size);
virtio_notify(VIRTIO_DEVICE(stream->s), buffer->vq);
QSIMPLEQ_REMOVE(&stream->queue,
buffer,
VirtIOSoundPCMBuffer,
entry);
virtio_snd_pcm_buffer_free(buffer);
}


/*
* AUD_* input callback.
*
* @data: VirtIOSoundPCMStream stream
* @available: number of bytes that can be read with AUD_read()
*/
static void virtio_snd_pcm_in_cb(void *data, int available)
{
VirtIOSoundPCMStream *stream = data;
VirtIOSoundPCMBuffer *buffer;
size_t size;

WITH_QEMU_LOCK_GUARD(&stream->queue_mutex) {
while (!QSIMPLEQ_EMPTY(&stream->queue)) {
buffer = QSIMPLEQ_FIRST(&stream->queue);
if (!virtio_queue_ready(buffer->vq)) {
return;
}
if (!stream->active) {
/* Stream has stopped, so do not perform AUD_read. */
return_rx_buffer(stream, buffer);
continue;
}

for (;;) {
size = AUD_read(stream->voice.in,
buffer->data + buffer->size,
MIN(available, (stream->params.period_bytes -
buffer->size)));
if (!size) {
available = 0;
break;
}
buffer->size += size;
available -= size;
if (buffer->size >= stream->params.period_bytes) {
return_rx_buffer(stream, buffer);
break;
}
if (!available) {
break;
}
}
if (!available) {
break;
}
}
}
}

/*
* Flush all buffer data from this output stream's queue into the driver's
* virtual queue.
*
* @stream: VirtIOSoundPCMStream *stream
*/
static inline void virtio_snd_pcm_flush(VirtIOSoundPCMStream *stream)
{
VirtIOSoundPCMBuffer *buffer;
void (*cb)(VirtIOSoundPCMStream *, VirtIOSoundPCMBuffer *) =
(stream->info.direction == VIRTIO_SND_D_OUTPUT) ? return_tx_buffer :
return_rx_buffer;

WITH_QEMU_LOCK_GUARD(&stream->queue_mutex) {
while (!QSIMPLEQ_EMPTY(&stream->queue)) {
buffer = QSIMPLEQ_FIRST(&stream->queue);
return_tx_buffer(stream, buffer);
cb(stream, buffer);
}
}
}
Expand Down

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