Re: [PATCH v13 04/10] admin: introduce virtio admin virtqueues

[Parav Pandit <parav@nvidia.com>]

On 5/5/2023 11:40 AM, Michael S. Tsirkin wrote:
> The admin virtqueues will be the first interface used to issue admin commands.
>
> Currently the virtio specification defines control virtqueue to manipulate
> features and configuration of the device it operates on:
> virtio-net, virtio-scsi, etc all have existing control virtqueues. However,
> control virtqueue commands are device type specific, which makes it very
> difficult to extend for device agnostic commands.
>
> Keeping the device-specific virtqueue separate from the admin virtqueue
> is simpler and has fewer potential problems. I don't think creating
> common infrastructure for device-specific control virtqueues across
> device types worthwhile or within the scope of this patch series.
>
> To support this requirement in a more generic way, this patch introduces
> a new admin virtqueue interface.
> The admin virtqueue can be seen as the virtqueue analog to a transport.
> The admin queue thus does nothing device type-specific (net, scsi, etc)
> and instead focuses on transporting the admin commands.
>
> We also support more than one admin virtqueue, for QoS and
> scalability requirements.
>
> Based-on-patch-by: Max Gurtovoy <mgurtovoy@nvidia.com>
> Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
> Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Parav Pandit <parav@nvidia.com>