Re: [Qemu-devel] [PATCH COLO-Frame v14 32/40] net/filter: Introduce a helper to add a filter to the netdev

[Hailiang Zhang]

On 2016/2/23 19:39, Hailiang Zhang wrote:
> On 2016/2/23 16:36, Jason Wang wrote:
> > On 02/18/2016 11:30 AM, Hailiang Zhang wrote:
> > > On 2016/2/18 11:19, Jason Wang wrote:
> > > > On 02/06/2016 05:28 PM, zhanghailiang wrote:
> > > > > We add a new helper function netdev_add_filter(),
> > > > > this function can help adding a filter object to a netdev.
> > > > >
> > > > > Signed-off-by: zhanghailiang <address@hidden>
> > > > > Cc: Jason Wang <address@hidden>
> > > > > Cc: Yang Hongyang <address@hidden>
> > > > > ---
> > > > >    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..0159080 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;
> > > >
> > > > I believe we've agreed that, we will remove this flag? And it seems that
> > > > it was not used by following patches.
> > >
> > > Oops, i forgot to remove this useless codes. 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);
> > > > >
> > > > > +NetFilterState *netdev_add_filter(const char *netdev_id,
> > > > > +                                  const char *filter_type,
> > > > > +                                  const char *filter_id,
> > > > > +                                  bool enabled,
> > > > > +                                  Error **errp);
> > > > > +
> > > > >    #endif /* QEMU_NET_FILTER_H */
> > > > > diff --git a/net/filter.c b/net/filter.c
> > > > > index 5551cf1..dbe9399 100644
> > > > > --- a/net/filter.c
> > > > > +++ b/net/filter.c
> > > > > @@ -177,6 +177,7 @@ static void netfilter_init(Object *obj)
> > > > >        * for netfilter will be enabled.
> > > > >        */
> > > > >        nf->enabled = true;
> > > > > +    nf->is_default = false;
> > > > >
> > > > >        object_property_add_str(obj, "netdev",
> > > > >                                netfilter_get_netdev_id,
> > > > > netfilter_set_netdev_id,
> > > > > @@ -232,6 +233,39 @@ static void netfilter_complete(UserCreatable
> > > > > *uc, Error **errp)
> > > > >        QTAILQ_INSERT_TAIL(&nf->netdev->filters, nf, next);
> > > > >    }
> > > > >
> > > > > +NetFilterState *netdev_add_filter(const char *netdev_id,
> > > > > +                                  const char *filter_type,
> > > > > +                                  const char *filter_id,
> > > > > +                                  bool enabled,
> > > > > +                                  Error **errp)
> > > > > +{
> > > > > +    NetClientState *nc = qemu_find_netdev(netdev_id);
> > > > > +    Object *filter;
> > > > > +    Error *local_err = NULL;
> > > > > +
> > > > > +    /* FIXME: Not support multiple queues */
> > > > > +    if (!nc || nc->queue_index > 1) {
> > > > > +        return NULL;
> > > > > +    }
> > > > > +    /* Not support vhost-net */
> > > > > +    if (get_vhost_net(nc)) {
> > > > > +        return NULL;
> > > > > +    }
> > > >
> > > > We will check those in netfilter_complete(), no?
> > >
> > > Yes, I'd like to check this more early here.
> > >
> > > Thanks,
> > > hailiang
> >
> > But what's the advantages here?
>
> Nothing special, here we just want to keep silent while users startup qemu
> with vhost=on, Or there will be an annoying "Vhost is not supported",
> since here we try to add each netdev a default filter.

Hmm, i made some mistake, we can remove the check here,
we call object_new_with_props(), with argument errp = NULL, there
won't be any complaint about vhost.
I will remove it in next version, thanks.

> Thanks,
> Hailiang