Re: [RFC PATCH 07/12] vhost: Add VhostVDPAStartOp operation

[Eugenio Perez Martin]

On Mon, Jul 18, 2022 at 10:50 AM Jason Wang <jasowang@redhat.com> wrote:
>
> On Sat, Jul 16, 2022 at 7:34 PM Eugenio Pérez <eperezma@redhat.com> wrote:
> >
> > It allows to run commands at start of the device, before it have enabled
> > any queue.
> >
> > Signed-off-by: Eugenio Pérez <eperezma@redhat.com>
> > ---
> >  hw/virtio/vhost-shadow-virtqueue.h | 3 +++
> >  include/hw/virtio/vhost-vdpa.h     | 5 +++++
> >  hw/virtio/vhost-vdpa.c             | 8 ++++++++
> >  3 files changed, 16 insertions(+)
> >
> > diff --git a/hw/virtio/vhost-shadow-virtqueue.h 
> > b/hw/virtio/vhost-shadow-virtqueue.h
> > index 03eb7ff670..210fe393cd 100644
> > --- a/hw/virtio/vhost-shadow-virtqueue.h
> > +++ b/hw/virtio/vhost-shadow-virtqueue.h
> > @@ -26,6 +26,8 @@ typedef struct SVQDescState {
> >  } SVQDescState;
> >
> >  typedef struct VhostShadowVirtqueue VhostShadowVirtqueue;
> > +typedef int (*ShadowVirtQueueStart)(VhostShadowVirtqueue *svq,
> > +                                    void *opaque);
> >
> >  /**
> >   * Callback to handle an avail buffer.
> > @@ -43,6 +45,7 @@ typedef int 
> > (*VirtQueueAvailCallback)(VhostShadowVirtqueue *svq,
> >                                        void *vq_callback_opaque);
> >
> >  typedef struct VhostShadowVirtqueueOps {
> > +    ShadowVirtQueueStart start;
>
> What's the difference between this and start_op?
>

This is a leftover, I'll delete for the next series.

Thanks!

> Thanks
>
> >      VirtQueueAvailCallback avail_handler;
> >  } VhostShadowVirtqueueOps;
> >
> > diff --git a/include/hw/virtio/vhost-vdpa.h b/include/hw/virtio/vhost-vdpa.h
> > index d10a89303e..b7d18b4e30 100644
> > --- a/include/hw/virtio/vhost-vdpa.h
> > +++ b/include/hw/virtio/vhost-vdpa.h
> > @@ -24,6 +24,10 @@ typedef struct VhostVDPAHostNotifier {
> >      void *addr;
> >  } VhostVDPAHostNotifier;
> >
> > +struct vhost_vdpa;
> > +/* Called after send DRIVER_OK but after enabling vrings */
> > +typedef int (*VhostVDPAStartOp)(struct vhost_vdpa *v);
> > +
> >  typedef struct vhost_vdpa {
> >      int device_fd;
> >      int index;
> > @@ -39,6 +43,7 @@ typedef struct vhost_vdpa {
> >      GPtrArray *shadow_vqs;
> >      const VhostShadowVirtqueueOps *shadow_vq_ops;
> >      void *shadow_vq_ops_opaque;
> > +    VhostVDPAStartOp start_op;
> >      struct vhost_dev *dev;
> >      VhostVDPAHostNotifier notifier[VIRTIO_QUEUE_MAX];
> >  } VhostVDPA;
> > diff --git a/hw/virtio/vhost-vdpa.c b/hw/virtio/vhost-vdpa.c
> > index 1d8829c619..48f031b8c0 100644
> > --- a/hw/virtio/vhost-vdpa.c
> > +++ b/hw/virtio/vhost-vdpa.c
> > @@ -1136,6 +1136,14 @@ static int vhost_vdpa_dev_start(struct vhost_dev 
> > *dev, bool started)
> >          if (unlikely(r)) {
> >              return r;
> >          }
> > +
> > +        if (v->start_op) {
> > +            r = v->start_op(v);
> > +            if (unlikely(r)) {
> > +                return r;
> > +            }
> > +        }
> > +
> >          vhost_vdpa_set_vring_ready(dev);
> >      } else {
> >          vhost_vdpa_reset_device(dev);
> > --
> > 2.31.1
> >
>