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

[Hailiang Zhang <zhang.zhanghailiang@huawei.com>]

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 <zhang.zhanghailiang@huawei.com>
>> ---
>> 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);
>>
>