I will make it an in-QEMU pci device. After it is done and the device is working, I can write a vhost-user daemon and move the device out of QEMU should it be needed. This way I'd already have the virtio-pci device tested out by the time I get to the vhost-user daemon. Also I'll be a lot more familiar to sound and virtio devices by then hopefully. I hope this is fine?
As for the implementation plan, I will start out by writing the structure for the device, `VirtIOSnd` or `VirtIOSound`. Since QEMU already has a base `VirtIODevice` with common implementation along with the `VirtQueue`s, this shouldn't be very difficult. Following this I will start implementing the methods mentioned in the `VirtIODeviceClass`. This would include creating a separate `virtio-sound-pci.c` file with the `realize`, `unrealize` and various init functions. After that, I will start writing the `get`, `set` and validate functions mentioned in the `VirtioDeviceClass`. QEMU already has an implementation for `start_ioeventfd` and `stop_ioeventfd`. This should get us done with the configuration plane. I am thinking of writing a few tests at this point. I will have to read about the qtest framework first though. This should take at most around a month. I am hoping to get it done earlier than that time (~3 weeks) if things go well. From this most of the time goes to tests. I am taking a bit of a margin to err on the side of caution. This now brings us to the dataplane and processing of the data. I think once the data plane is successfully implemented, processing shouldn't take a lot of time. Once the control queue, event queue, tx queue and rx queues are implemented, I can start implementing the Jack and PCM control requests. I can write tests after completing each of these phases. As of right now, I am not awake enough to give a clear plan on the data plane implementation. I will clear the plan out tomorrow. The dataplane along with the processing should at most take a little over a month to implement I'd guess. I will make sure I write a follow up mail tomorrow with a clearer and complete plan. Apologies for any statements that weren't very clear or mistakes in the language that I used. - Shreyansh Chouhan
