Re: [Qemu-devel] [PATCH v3 2/4] net/filter: Introduce a helper to add a filter to the netdev

[Hailiang Zhang]

On 2016/2/2 11:14, Yang Hongyang wrote:
> On 02/01/2016 08:01 PM, zhanghailiang wrote:
> > We add a new helper function netdev_add_filter(), this function
> > can help adding a filter object to a netdev.
> > Besides, we add a is_default member for struct NetFilterState
> > to indicate whether the filter is default or not.
> >
> > Signed-off-by: zhanghailiang <address@hidden>
> > ---
> > v3:
> >   - Use object_new_with_props() instead of object_create()
> >    (Daniel's suggestion)
> > v2:
> >   - Re-implement netdev_add_filter() by re-using object_create()
> >    (Jason's suggestion)
> > ---
> >   include/net/filter.h |  7 +++++++
> >   net/filter.c         | 34 ++++++++++++++++++++++++++++++++++
> >   2 files changed, 41 insertions(+)
> >
> > diff --git a/include/net/filter.h b/include/net/filter.h
> > index af3c53c..661abef 100644
> > --- a/include/net/filter.h
> > +++ b/include/net/filter.h
> > @@ -55,6 +55,7 @@ struct NetFilterState {
> >       char *netdev_id;
> >       NetClientState *netdev;
> >       NetFilterDirection direction;
> > +    bool is_default;
>
> You added a member, but seems did not initialize it. although the
> default behavior of a struct init is 0, a explicit is_defuault=false
> is better IMO.

OK, i will fix it in next version.

> >       bool enabled;
> >       QTAILQ_ENTRY(NetFilterState) next;
> >   };
> > @@ -74,4 +75,10 @@ ssize_t qemu_netfilter_pass_to_next(NetClientState *sender,
> >                                       int iovcnt,
> >                                       void *opaque);
> >
> > +void netdev_add_filter(const char *netdev_id,
> > +                       const char *filter_type,
> > +                       const char *filter_id,
> > +                       bool is_default,
> > +                       Error **errp);
> > +
> >   #endif /* QEMU_NET_FILTER_H */
> > diff --git a/net/filter.c b/net/filter.c
> > index d08a2be..7f9df57 100644
> > --- a/net/filter.c
> > +++ b/net/filter.c
> > @@ -214,6 +214,40 @@ static void netfilter_complete(UserCreatable *uc, Error 
> > **errp)
> >       QTAILQ_INSERT_TAIL(&nf->netdev->filters, nf, next);
> >   }
> >
> > +void netdev_add_filter(const char *netdev_id,
> > +                       const char *filter_type,
> > +                       const char *filter_id,
> > +                       bool is_default,
> > +                       Error **errp)
>
> We could assume all calls to this API is adding default filter.
> so is_default is useness.

Make sense, i will rename this API to netdev_add_default_filter()
and drop the is_default parameter.

Thanks,
Hailiang

> > +{
> > +    NetClientState *nc = qemu_find_netdev(netdev_id);
> > +    Object *filter;
> > +    NetFilterState *nf;
> > +    Error *local_err = NULL;
> > +
> > +    /* FIXME: Not support multiple queues */
> > +    if (!nc || nc->queue_index > 1) {
> > +        return;
> > +    }
> > +    /* Not support vhost-net */
> > +    if (get_vhost_net(nc)) {
> > +        return;
> > +    }
> > +    filter = object_new_with_props(filter_type,
> > +                        object_get_objects_root(),
> > +                        filter_id,
> > +                        &local_err,
> > +                        "netdev", netdev_id,
> > +                        "status", is_default ? "disable" : "enable",
> > +                        NULL);
> > +    if (local_err) {
> > +        error_propagate(errp, local_err);
> > +        return;
> > +    }
> > +    nf = NETFILTER(filter);
> > +    nf->is_default = is_default;
> > +}
> > +
> >   static void netfilter_finalize(Object *obj)
> >   {
> >       NetFilterState *nf = NETFILTER(obj);