[dpdk-dev] [RFC 06/10] virtio: use software vlan stripping

[Ouyang, Changchun]

> -----Original Message-----
> From: Stephen Hemminger [mailto:stephen at networkplumber.org]
> Sent: Wednesday, August 27, 2014 12:24 AM
> To: Ouyang, Changchun
> Cc: dev at dpdk.org
> Subject: Re: [RFC 06/10] virtio: use software vlan stripping
> 
> On Tue, 26 Aug 2014 08:37:11 +0000
> "Ouyang, Changchun" <changchun.ouyang at intel.com> wrote:
> 
> > Hi Stephen,
> >
> > Would you please describe the use scenario for the front end rx vlan strip
> and tx vlan insertion?
> > In our current implementation, backend will strip vlan tag for RX, and insert
> vlan tag for TX.
> >
> > Thanks
> > Changchun
> 
> First, we don't have to do software VLAN strip on our backend if we do this.
> And this way we can always use VLAN insert on transmit. Otherwise you
> have to introduce special case because there is no DPDK API to determine if
> device does or does not do VLAN handling.
> 

How the virtio frontend tell backend whether it has software VLAN strip feature or not?
It seems no feature bit to negotiate it.

Thanks
Changchun