[virtio-dev] Re: [PATCH 0/5] virtio: introduce SUSPEND bit and vq state

Michael S. Tsirkin
2023-09-14T11:14:21Z

On Wed, Sep 06, 2023 at 04:16:32PM +0800, Zhu Lingshan wrote:
> This series introduces
> 1)a new SUSPEND bit in the device status
> Which is used to suspend the device, so that the device states
> and virtqueue states are stabilized.
>
> 2)virtqueue state and its accessor, to get and set last_avail_idx
> and last_used_idx of virtqueues.
>
> The main usecase of these new facilities is Live Migration.
>
> Future work: dirty page tracking and in-flight descriptors.
> This series addresses many comments from Jason, Stefan and Eugenio
> from RFC series.

Compared to Parav's patchset this is much less functional.

Assuming that one goes in, can't we add ability to submit
admin commands through MMIO on the device itself and be done with it?

> Zhu Lingshan (5):
> virtio: introduce vq state as basic facility
> virtio: introduce SUSPEND bit in device status
> virtqueue: constraints for virtqueue state
> virtqueue: ignore resetting vqs when SUSPEND
> virtio-pci: implement VIRTIO_F_QUEUE_STATE
>
> content.tex | 118 ++++++++++++++++++++++++++++++++++++++++++++++
> transport-pci.tex | 18 +++++++
> 2 files changed, 136 insertions(+)
>
> --
> 2.35.3