Re: [PATCH v3 6/7] vhost_net: Add NetClientInfo prepare callback

[Jason Wang]

On Thu, Aug 4, 2022 at 3:52 PM Eugenio Perez Martin <eperezma@redhat.com> wrote:
>
> On Thu, Aug 4, 2022 at 6:46 AM Jason Wang <jasowang@redhat.com> wrote:
> >
> >
> > 在 2022/8/4 01:18, Eugenio Pérez 写道:
> > > This is used by the backend to perform actions before the device is
> > > started.
> > >
> > > In particular, vdpa will use it to isolate CVQ in its own ASID if
> > > possible, and start SVQ unconditionally only in CVQ.
> > >
> > > Signed-off-by: Eugenio Pérez <eperezma@redhat.com>
> > > ---
> > >   include/net/net.h  | 2 ++
> > >   hw/net/vhost_net.c | 4 ++++
> > >   2 files changed, 6 insertions(+)
> > >
> > > diff --git a/include/net/net.h b/include/net/net.h
> > > index a8d47309cd..efa6448886 100644
> > > --- a/include/net/net.h
> > > +++ b/include/net/net.h
> > > @@ -44,6 +44,7 @@ typedef struct NICConf {
> > >
> > >   typedef void (NetPoll)(NetClientState *, bool enable);
> > >   typedef bool (NetCanReceive)(NetClientState *);
> > > +typedef void (NetPrepare)(NetClientState *);
> > >   typedef int (NetLoad)(NetClientState *);
> > >   typedef ssize_t (NetReceive)(NetClientState *, const uint8_t *, size_t);
> > >   typedef ssize_t (NetReceiveIOV)(NetClientState *, const struct iovec *, 
> > > int);
> > > @@ -72,6 +73,7 @@ typedef struct NetClientInfo {
> > >       NetReceive *receive_raw;
> > >       NetReceiveIOV *receive_iov;
> > >       NetCanReceive *can_receive;
> > > +    NetPrepare *prepare;
> > >       NetLoad *load;
> > >       NetCleanup *cleanup;
> > >       LinkStatusChanged *link_status_changed;
> > > diff --git a/hw/net/vhost_net.c b/hw/net/vhost_net.c
> > > index a9bf72dcda..bbbb6d759b 100644
> > > --- a/hw/net/vhost_net.c
> > > +++ b/hw/net/vhost_net.c
> > > @@ -244,6 +244,10 @@ static int vhost_net_start_one(struct vhost_net *net,
> > >       struct vhost_vring_file file = { };
> > >       int r;
> > >
> > > +    if (net->nc->info->prepare) {
> > > +        net->nc->info->prepare(net->nc);
> > > +    }
> >
> >
> > Any chance we can reuse load()?
> >
>
> We would be setting the ASID of CVQ after DRIVER_OK, vring
> addresses... if we move to load.

Ok, then this patch should be fine.

Thanks

>
> Thanks!
>
> > Thanks
> >
> >
> > > +
> > >       r = vhost_dev_enable_notifiers(&net->dev, dev);
> > >       if (r < 0) {
> > >           goto fail_notifiers;
> >
>