Re: [Qemu-devel] [PATCH] net/filter-redirector:Add filter-redirector

[Zhang Chen]

On 02/29/2016 03:11 PM, Jason Wang wrote:
> On 02/24/2016 05:03 PM, Zhang Chen wrote:
> > If queue=rx, filter-redirector will get the packet that guest send,
> > then redirect
> > to outdev(if none, do nothing). but queue=rx/tx/all not related to
> > indev. please
> > look the flow chart below. queue=xxx just work for one
> > way(filter->outdev).
> >
> >                                filter
> >                                  +
> >                                  |
> >                                  |
> >                 redirector       |
> >                  +-------------------------+
> >                  |               |         |
> >                  |               |         |
> >                  |               |         |
> >     indev +----------------+     +---------------->  outdev
> >                  |         |               |
> >                  |         |               |
> >                  |         |               |
> >                  +-------------------------+
> >                            |
> >                            |
> >                            v
> >                         filter
> >
> >                            |
> >
> >                            |
> >
> >                            v
> >                         filter ........ filter ...... guest
> This looks a violation on the assumption of current filter behavior.
> Each filter should only talk to the 'next' or 'prev' filter on the chain
> (depends on the direction) or netdev when queue=rx or netdev's peer when
> queue=tx.
>
> And in fact there's subtle differences with your patch:
>
> When queue='all' since you force nf->netdev as sender, direction is
> NET_FILTER_DIRECTION_TX, the packet will be passed to 'next' filter on
> the chain.
> When queue='rx', direction is NET_FILTER_DIRECTION_RX, the packet will
> be pass to 'prev' filter on the chain.
>
> So as you can see, 'all' is ambiguous here. I think we should keep
> current behavior by redirecting traffic to netdev when queue='rx'. For
> queue='all', maybe we need redirect the traffic to both netdev and
> netdev's peer.

OK, I will change usage to :

-filter-redirector,id=r0,netdev=hn0,queue=tx/rx/all,outdev=s1,indev=s0,in_direction=tx/rx
How about this?

I will fix it in V3.

Thanks
zhangchen

> .

--
Thanks
zhangchen