Re: [RFC 1/2] wireless: add ieee80211_asmdu_to_8023s

Johannes Berg
2009-11-27T09:33:27Z

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On Fri, 2009-11-27 at 17:30 +0800, Zhu Yi wrote:
> On Fri, 2009-11-27 at 17:20 +0800, Johannes Berg wrote:
> > Is it? I don't think so. Many drivers go up beyond that as far as I
> > know. Then some do different things like putting it in a different DMA
> > block.
> >
> > > While for those drivers really need a bigger
> > > extra headroom and support Rx aggregation, this probably means
> > > ieee80211_skb_resize. But the resize should always happen for every
> > > packet from the IP stack, right?
> >
> > No, davem and I optimised that away a long time ago via using
> > netdev->needed_headroom and netdev->needed_tailroom. It even works for
> > bridges and their slave devices, iirc.
>
> I missed this. Will check it. If so, I'll add another parameter to pass
> the extra hw tx headroom to ieee80211_asmdu_to_8023s.

The thing is that I'm not even sure if we can possibly forward a frame
after this deaggregation. I'll poke at the code.