On 12/20/20 10:13 PM, Maxime Coquelin wrote:
> This series significantly rework Virtio PMD to improve
> the Virtio-user PMD and its backends integration.
>
> First part of the series (first 21 patches) removes the
> dependency of Virtio-user ethdev on Virtio PCI, by
> creating generic files, adding per-bus meta data, ...
>
> Main (if not single) functionnal change of this first
> part is to remove the hack for Virtio-user to work in
> IOVA as PA mode, this hack being very fragile. Now, the
> user has to manually pass --iova-mode=va in EAL
> parameters, otherwise vdev probe will fail. In v21.11,
> when ABI/API can be changed, I will add vdev driver
> flags so that the Virtio-user PMD can request IOVA as VA
> mode to be used.
>
> Second part of the series reworks Virtio-user internal,
> by reworking the requests handling so that vDPA and Kernel
> backends no more hack into being Vhost-user backend. It
> implies implementing new ops for all the request types.
> Also, all the backend specific actions are moved from the
> virtio_user_dev.c and virtio_user_ethdev.c to their
> backend files.
>
> Only functionnal change in this second part is making the
> Vhost-user server mode blocking at init time, as long as
> a client is not connected. The goal of this change is to
> make the Vhost-user support much more robust, as without
> blocking, the driver has to assume features that are going
> to be supported by the client, which is very fragile and
> error prone. As a side-effect, it also simplifies the
> logic nin several place of the virtio-user PMD.
>
> Plese note that I haven't tested the last 5 patches yet,
> I will conduct more testing early next week.
I forgot to add the remaining things to do in next release:
1. More testing
2. Rebase on top of Vhost-vDPA batching support
3. Rebase on top of Olivier's protocol features fix
4. (Maybe) Loosen restrictions on IOVA as VA mode, by making Vhost-
backend to use IOVA instead of directly VAs, but still warn IOVA
as VA mode is advised to ensure init won't fail.
Regards,
Maxime
