From: Emmanouil Pitsidianakis <manos.pitsidiana...@linaro.org> 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: Emmanouil Pitsidianakis <manos.pitsidiana...@linaro.org> Reviewed-by: Alex Bennée <alex.ben...@linaro.org> --- hw/virtio/trace-events | 3 +- hw/virtio/virtio-snd.c | 262 +++++++++++++++++++++++++++++++++++------ 2 files changed, 230 insertions(+), 35 deletions(-) diff --git a/hw/virtio/trace-events b/hw/virtio/trace-events index a31531970d..56a2f44981 100644 --- a/hw/virtio/trace-events +++ b/hw/virtio/trace-events @@ -172,4 +172,5 @@ 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" diff --git a/hw/virtio/virtio-snd.c b/hw/virtio/virtio-snd.c index 5e9513fb26..636ea08c1a 100644 --- a/hw/virtio/virtio-snd.c +++ b/hw/virtio/virtio-snd.c @@ -1,40 +1,41 @@ /* * VIRTIO Sound Device conforming to * * "Virtual I/O Device (VIRTIO) Version 1.2 * Committee Specification Draft 01 * 09 May 2022" * * <https://docs.oasis-open.org/virtio/virtio/v1.2/csd01/virtio-v1.2-csd01.html#x1-52900014> * * Copyright (c) 2023 Emmanouil Pitsidianakis <manos.pitsidiana...@linaro.org> * Copyright (C) 2019 OpenSynergy GmbH * * This work is licensed under the terms of the GNU GPL, version 2 or * (at your option) any later version. See the COPYING file in the * top-level directory. */ #include "qemu/osdep.h" #include "qemu/iov.h" #include "qemu/log.h" #include "qemu/error-report.h" #include "include/qemu/lockable.h" #include "sysemu/runstate.h" #include "trace.h" #include "qapi/error.h" #include "hw/virtio/virtio-snd.h" #include "hw/core/cpu.h" #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) @@ -403,87 +404,96 @@ static void virtio_snd_get_qemu_audsettings(audsettings *as, /* * Close a stream and free all its resources. * * @stream: VirtIOSoundPCMStream *stream */ 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; } } } /* * Prepares a VirtIOSound card stream. * Returns the response status code. (VIRTIO_SND_S_*). * * @s: VirtIOSound device * @stream_id: stream id */ static uint32_t virtio_snd_pcm_prepare(VirtIOSound *s, uint32_t stream_id) { audsettings as; virtio_snd_pcm_set_params *params; VirtIOSoundPCMStream *stream; if (s->pcm->streams == NULL || s->pcm->pcm_params == NULL || stream_id >= s->snd_conf.streams) { return cpu_to_le32(VIRTIO_SND_S_BAD_MSG); } params = virtio_snd_pcm_get_params(s, stream_id); if (params == NULL) { return cpu_to_le32(VIRTIO_SND_S_BAD_MSG); } stream = virtio_snd_pcm_get_stream(s, stream_id); if (stream == NULL) { stream = g_new0(VirtIOSoundPCMStream, 1); stream->active = false; stream->id = stream_id; stream->pcm = s->pcm; stream->s = s; qemu_mutex_init(&stream->queue_mutex); QSIMPLEQ_INIT(&stream->queue); QSIMPLEQ_INIT(&stream->invalid); /* * stream_id >= s->snd_conf.streams was checked before so this is * in-bounds */ s->pcm->streams[stream_id] = stream; } virtio_snd_get_qemu_audsettings(&as, params); stream->info.direction = stream_id < s->snd_conf.streams / 2 + (s->snd_conf.streams & 1) ? VIRTIO_SND_D_OUTPUT : VIRTIO_SND_D_INPUT; stream->info.hdr.hda_fn_nid = VIRTIO_SOUND_HDA_FN_NID; stream->info.features = 0; stream->info.channels_min = 1; stream->info.channels_max = as.nchannels; stream->info.formats = supported_formats; stream->info.rates = supported_rates; stream->params = *params; stream->positions[0] = VIRTIO_SND_CHMAP_FL; stream->positions[1] = VIRTIO_SND_CHMAP_FR; stream->as = as; if (stream->info.direction == VIRTIO_SND_D_OUTPUT) { stream->voice.out = AUD_open_out(&s->card, stream->voice.out, "virtio-sound.out", stream, virtio_snd_pcm_out_cb, &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); } @@ -536,54 +546,56 @@ static void virtio_snd_handle_pcm_prepare(VirtIOSound *s, /* * Handles VIRTIO_SND_R_PCM_START. * * @s: VirtIOSound device * @cmd: The request command queue element from VirtIOSound cmdq field * @start: whether to start or stop the device */ static void virtio_snd_handle_pcm_start_stop(VirtIOSound *s, virtio_snd_ctrl_command *cmd, bool start) { VirtIOSoundPCMStream *stream; virtio_snd_pcm_hdr req; uint32_t stream_id; size_t msg_sz = iov_to_buf(cmd->elem->out_sg, cmd->elem->out_num, 0, &req, sizeof(virtio_snd_pcm_hdr)); if (msg_sz != sizeof(virtio_snd_pcm_hdr)) { qemu_log_mask(LOG_GUEST_ERROR, "%s: virtio-snd command size incorrect %zu vs \ %zu\n", __func__, msg_sz, sizeof(virtio_snd_pcm_hdr)); cmd->resp.code = cpu_to_le32(VIRTIO_SND_S_BAD_MSG); return; } stream_id = le32_to_cpu(req.stream_id); cmd->resp.code = cpu_to_le32(VIRTIO_SND_S_OK); trace_virtio_snd_handle_pcm_start_stop(start ? "VIRTIO_SND_R_PCM_START" : "VIRTIO_SND_R_PCM_STOP", stream_id); stream = virtio_snd_pcm_get_stream(s, stream_id); if (stream) { WITH_QEMU_LOCK_GUARD(&stream->queue_mutex) { stream->active = start; } 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); cmd->resp.code = cpu_to_le32(VIRTIO_SND_S_BAD_MSG); return; } stream->active = start; } /* * Returns the number of I/O messages that are being processed. * * @stream: VirtIOSoundPCMStream */ @@ -804,80 +816,122 @@ static void virtio_snd_handle_ctrl(VirtIODevice *vdev, VirtQueue *vq) /* * The event virtqueue handler. * Not implemented yet. * * @vdev: VirtIOSound device * @vq: event vq */ static void virtio_snd_handle_event(VirtIODevice *vdev, VirtQueue *vq) { qemu_log_mask(LOG_UNIMP, "virtio_snd: event queue is unimplemented.\n"); 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 * return them after the for loop. */ bool must_empty_invalid_queue = false; if (!virtio_queue_ready(vq)) { return; } - trace_virtio_snd_handle_xfer(); + trace_virtio_snd_handle_tx_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 tx_err; } stream_id = le32_to_cpu(hdr.stream_id); if (stream_id >= s->snd_conf.streams || s->pcm->streams[stream_id] == NULL) { goto tx_err; } stream = s->pcm->streams[stream_id]; if (stream->info.direction != VIRTIO_SND_D_OUTPUT) { goto tx_err; } WITH_QEMU_LOCK_GUARD(&stream->queue_mutex) { size = iov_size(elem->out_sg, elem->out_num) - msg_sz; buffer = g_malloc0(sizeof(VirtIOSoundPCMBuffer) + size); buffer->elem = elem; buffer->populated = false; buffer->vq = vq; buffer->size = size; buffer->offset = 0; QSIMPLEQ_INSERT_TAIL(&stream->queue, buffer, entry); } continue; @@ -885,44 +939,96 @@ static void virtio_snd_handle_tx(VirtIODevice *vdev, VirtQueue *vq) tx_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) { - 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) @@ -954,82 +1060,82 @@ virtio_snd_vm_state_change(void *opaque, bool running, static void virtio_snd_realize(DeviceState *dev, Error **errp) { ERRP_GUARD(); VirtIOSound *vsnd = VIRTIO_SND(dev); VirtIODevice *vdev = VIRTIO_DEVICE(dev); virtio_snd_pcm_set_params default_params = { 0 }; uint32_t status; vsnd->pcm = NULL; vsnd->vmstate = qemu_add_vm_change_state_handler(virtio_snd_vm_state_change, vsnd); trace_virtio_snd_realize(vsnd); vsnd->pcm = g_new0(VirtIOSoundPCM, 1); vsnd->pcm->snd = vsnd; vsnd->pcm->streams = g_new0(VirtIOSoundPCMStream *, vsnd->snd_conf.streams); vsnd->pcm->pcm_params = g_new0(virtio_snd_pcm_set_params, vsnd->snd_conf.streams); virtio_init(vdev, VIRTIO_ID_SOUND, sizeof(virtio_snd_config)); virtio_add_feature(&vsnd->features, VIRTIO_F_VERSION_1); /* set number of jacks and streams */ if (vsnd->snd_conf.jacks > 8) { error_setg(errp, "Invalid number of jacks: %"PRIu32, vsnd->snd_conf.jacks); return; } if (vsnd->snd_conf.streams < 1 || vsnd->snd_conf.streams > 10) { error_setg(errp, "Invalid number of streams: %"PRIu32, vsnd->snd_conf.streams); return; } if (vsnd->snd_conf.chmaps > VIRTIO_SND_CHMAP_MAX_SIZE) { error_setg(errp, "Invalid number of channel maps: %"PRIu32, vsnd->snd_conf.chmaps); return; } AUD_register_card("virtio-sound", &vsnd->card, errp); /* set default params for all streams */ default_params.features = 0; default_params.buffer_bytes = cpu_to_le32(8192); default_params.period_bytes = cpu_to_le32(2048); default_params.channels = 2; default_params.format = VIRTIO_SND_PCM_FMT_S16; default_params.rate = VIRTIO_SND_PCM_RATE_48000; vsnd->queues[VIRTIO_SND_VQ_CONTROL] = virtio_add_queue(vdev, 64, virtio_snd_handle_ctrl); 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); for (uint32_t i = 0; i < vsnd->snd_conf.streams; i++) { status = virtio_snd_set_pcm_params(vsnd, i, &default_params); if (status != cpu_to_le32(VIRTIO_SND_S_OK)) { error_setg(errp, "Can't initalize stream params, device responded with %s.", print_code(status)); return; } status = virtio_snd_pcm_prepare(vsnd, i); if (status != cpu_to_le32(VIRTIO_SND_S_OK)) { error_setg(errp, "Can't prepare streams, device responded with %s.", print_code(status)); return; } } } @@ -1059,76 +1165,164 @@ static inline void return_tx_buffer(VirtIOSoundPCMStream *stream, /* * AUD_* output callback. * * @data: VirtIOSoundPCMStream stream * @available: number of bytes that can be written with AUD_write() */ static void virtio_snd_pcm_out_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_write. */ return_tx_buffer(stream, buffer); continue; } if (!buffer->populated) { iov_to_buf(buffer->elem->out_sg, buffer->elem->out_num, sizeof(virtio_snd_pcm_xfer), buffer->data, buffer->size); buffer->populated = true; } for (;;) { size = AUD_write(stream->voice.out, buffer->data + buffer->offset, MIN(buffer->size, available)); assert(size <= MIN(buffer->size, available)); if (size == 0) { /* break out of both loops */ available = 0; break; } buffer->size -= size; buffer->offset += size; available -= size; if (buffer->size < 1) { return_tx_buffer(stream, buffer); break; } if (!available) { break; } } if (!available) { break; } } } } /* - * 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); } } } -- 2.39.2