Hi Emmanouil,
On 28/8/23 21:55, Emmanouil Pitsidianakis wrote:
Receive guest requests in the control (CTRL) queue of the virtio sound
device and reply with a NOT SUPPORTED error to all control commands.
The receiving handler is virtio_snd_handle_ctrl(). It stores all control
messages in the queue in the device's command queue. Then it calls
virtio_snd_process_cmdq() to handle each message.
The handler is process_cmd() which replies with VIRTIO_SND_S_NOT_SUPP.
Based-on:
https://github.com/OpenSynergy/qemu/commit/5a2f350eec5d157b90d9c7b40a8e603f4da92471
Reviewed-by: Alex Bennée <alex.ben...@linaro.org>
Signed-off-by: Igor Skalkin <igor.skal...@opensynergy.com>
Signed-off-by: Anton Yakovlev <anton.yakov...@opensynergy.com>
Signed-off-by: Emmanouil Pitsidianakis <manos.pitsidiana...@linaro.org>
---
hw/virtio/trace-events | 4 +
hw/virtio/virtio-snd.c | 227 ++++++++++++++++++++++++++++++++-
include/hw/virtio/virtio-snd.h | 70 +++++++++-
3 files changed, 292 insertions(+), 9 deletions(-)
/*
- * Queue handler stub.
+ * The actual processing done in virtio_snd_process_cmdq().
+ *
+ * @s: VirtIOSound device
+ * @cmd: control command request
+ */
+static inline void
+process_cmd(VirtIOSound *s, virtio_snd_ctrl_command *cmd)
+{
+ size_t sz = iov_to_buf(cmd->elem->out_sg,
+ cmd->elem->out_num,
+ 0,
+ &cmd->ctrl,
+ sizeof(cmd->ctrl));
+ if (sz != sizeof(cmd->ctrl)) {
+ qemu_log_mask(LOG_GUEST_ERROR,
+ "%s: virtio-snd command size incorrect %zu vs \
+ %zu\n", __func__, sz, sizeof(cmd->ctrl));
+ return;
+ }
+
+ trace_virtio_snd_handle_code(cmd->ctrl.code,
+ print_code(cmd->ctrl.code));
+
+ switch (cmd->ctrl.code) {
+ case VIRTIO_SND_R_JACK_INFO:
+ case VIRTIO_SND_R_JACK_REMAP:
+ qemu_log_mask(LOG_UNIMP,
+ "virtio_snd: jack functionality is unimplemented.");
+ cmd->resp.code = VIRTIO_SND_S_NOT_SUPP;
+ break;
+ case VIRTIO_SND_R_PCM_INFO:
+ case VIRTIO_SND_R_PCM_SET_PARAMS:
+ case VIRTIO_SND_R_PCM_PREPARE:
+ case VIRTIO_SND_R_PCM_START:
+ case VIRTIO_SND_R_PCM_STOP:
+ case VIRTIO_SND_R_PCM_RELEASE:
+ cmd->resp.code = VIRTIO_SND_S_NOT_SUPP;
+ break;
+ case VIRTIO_SND_R_CHMAP_INFO:
+ qemu_log_mask(LOG_UNIMP,
+ "virtio_snd: chmap info functionality is unimplemented.");
+ trace_virtio_snd_handle_chmap_info();
+ cmd->resp.code = VIRTIO_SND_S_NOT_SUPP;
+ break;
+ default:
+ /* error */
+ error_report("virtio snd header not recognized: %"PRIu32,
+ cmd->ctrl.code);
+ cmd->resp.code = VIRTIO_SND_S_BAD_MSG;
+ }
+
+ iov_from_buf(cmd->elem->in_sg,
+ cmd->elem->in_num,
+ 0,
+ &cmd->resp,
+ sizeof(cmd->resp));
+ virtqueue_push(cmd->vq, cmd->elem, sizeof(cmd->elem));
+ virtio_notify(VIRTIO_DEVICE(s), cmd->vq);
I have very few understanding of virtio, but I'm wondering here,
since this function is called under cmdq_mutex(), could it be
useful to batch the queue by calling virtio_notify() only once
in the caller once the whole cmdq is processed ...
+}
+
+/*
+ * Consume all elements in command queue.
+ *
+ * @s: VirtIOSound device
+ */
+static void virtio_snd_process_cmdq(VirtIOSound *s)
+{
+ virtio_snd_ctrl_command *cmd;
+
+ if (unlikely(qatomic_read(&s->processing_cmdq))) {
+ return;
+ }
+
+ WITH_QEMU_LOCK_GUARD(&s->cmdq_mutex) {
+ qatomic_set(&s->processing_cmdq, true);
+ while (!QTAILQ_EMPTY(&s->cmdq)) {
+ cmd = QTAILQ_FIRST(&s->cmdq);
+
+ /* process command */
+ process_cmd(s, cmd);
+
+ QTAILQ_REMOVE(&s->cmdq, cmd, next);
+
+ g_free(cmd);
+ }
... here?
+ qatomic_set(&s->processing_cmdq, false);
+ }
+}
