Re: [PATCH for 8.0 v8 06/12] vdpa: extract vhost_vdpa_svq_allocate_iova_tree

[Jason Wang <jasowang@xxxxxxxxxx>]

On Wed, Nov 30, 2022 at 3:40 PM Eugenio Perez Martin
<eperezma@xxxxxxxxxx> wrote:
>
> On Wed, Nov 30, 2022 at 7:43 AM Jason Wang <jasowang@xxxxxxxxxx> wrote:
> >
> > On Thu, Nov 24, 2022 at 11:52 PM Eugenio Pérez <eperezma@xxxxxxxxxx> wrote:
> > >
> > > It can be allocated either if all virtqueues must be shadowed or if
> > > vdpa-net detects it can shadow only cvq.
> > >
> > > Extract in its own function so we can reuse it.
> > >
> > > Signed-off-by: Eugenio Pérez <eperezma@xxxxxxxxxx>
> > > ---
> > >  net/vhost-vdpa.c | 29 +++++++++++++++++------------
> > >  1 file changed, 17 insertions(+), 12 deletions(-)
> > >
> > > diff --git a/net/vhost-vdpa.c b/net/vhost-vdpa.c
> > > index 88e0eec5fa..9ee3bc4cd3 100644
> > > --- a/net/vhost-vdpa.c
> > > +++ b/net/vhost-vdpa.c
> > > @@ -240,6 +240,22 @@ static NetClientInfo net_vhost_vdpa_info = {
> > >          .check_peer_type = vhost_vdpa_check_peer_type,
> > >  };
> > >
> > > +static int vhost_vdpa_get_iova_range(int fd,
> > > +                                     struct vhost_vdpa_iova_range *iova_range)
> > > +{
> > > +    int ret = ioctl(fd, VHOST_VDPA_GET_IOVA_RANGE, iova_range);
> > > +
> > > +    return ret < 0 ? -errno : 0;
> > > +}
> >
> > I don't get why this needs to be moved to net specific code.
> >
>
> It was already in net, this code just extracted it in its own function.

Ok, there's similar function that in vhost-vdpa.c:

static void vhost_vdpa_get_iova_range(struct vhost_vdpa *v)
{
    int ret = vhost_vdpa_call(v->dev, VHOST_VDPA_GET_IOVA_RANGE,
                              &v->iova_range);
    if (ret != 0) {
        v->iova_range.first = 0;
        v->iova_range.last = UINT64_MAX;
    }

    trace_vhost_vdpa_get_iova_range(v->dev, v->iova_range.first,
                                    v->iova_range.last);
}

I think we can reuse that.

Thanks

>
> It's done in net because iova_tree must be the same for all queuepair
> vhost, so we need to allocate before them.
>
> Thanks!
>
> > Thanks
> >
> > > +
> > > +static VhostIOVATree *vhost_vdpa_svq_allocate_iova_tree(int vdpa_device_fd)
> > > +{
> > > +    struct vhost_vdpa_iova_range iova_range;
> > > +
> > > +    vhost_vdpa_get_iova_range(vdpa_device_fd, &iova_range);
> > > +    return vhost_iova_tree_new(iova_range.first, iova_range.last);
> > > +}
> > > +
> > >  static void vhost_vdpa_cvq_unmap_buf(struct vhost_vdpa *v, void *addr)
> > >  {
> > >      VhostIOVATree *tree = v->iova_tree;
> > > @@ -587,14 +603,6 @@ static NetClientState *net_vhost_vdpa_init(NetClientState *peer,
> > >      return nc;
> > >  }
> > >
> > > -static int vhost_vdpa_get_iova_range(int fd,
> > > -                                     struct vhost_vdpa_iova_range *iova_range)
> > > -{
> > > -    int ret = ioctl(fd, VHOST_VDPA_GET_IOVA_RANGE, iova_range);
> > > -
> > > -    return ret < 0 ? -errno : 0;
> > > -}
> > > -
> > >  static int vhost_vdpa_get_features(int fd, uint64_t *features, Error **errp)
> > >  {
> > >      int ret = ioctl(fd, VHOST_GET_FEATURES, features);
> > > @@ -690,14 +698,11 @@ int net_init_vhost_vdpa(const Netdev *netdev, const char *name,
> > >      }
> > >
> > >      if (opts->x_svq) {
> > > -        struct vhost_vdpa_iova_range iova_range;
> > > -
> > >          if (!vhost_vdpa_net_valid_svq_features(features, errp)) {
> > >              goto err_svq;
> > >          }
> > >
> > > -        vhost_vdpa_get_iova_range(vdpa_device_fd, &iova_range);
> > > -        iova_tree = vhost_iova_tree_new(iova_range.first, iova_range.last);
> > > +        iova_tree = vhost_vdpa_svq_allocate_iova_tree(vdpa_device_fd);
> > >      }
> > >
> > >      ncs = g_malloc0(sizeof(*ncs) * queue_pairs);
> > > --
> > > 2.31.1
> > >
> >
>