On Fri, Feb 06, 2009 at 09:28:22PM +1100, Herbert Xu wrote:

On Fri, Feb 06, 2009 at 09:51:20AM +0000, Jarek Poplawski wrote:

quoted

OK, but since there is not so much difference, and we need to waste
it in some cases anyway, plus handle it later some special way, I'm
a bit in doubt.

Well the thing is cards that don't support SG on tx probably
don't support jumbo frames either.

?? I mean this 128 byte chunk would be hard to reuse after copying
to skb->data, and if reused, we could miss this for some NICs on TX,
so the whole packed would need a copy.

BTW, David mentioned something simple like sk_sndmsg_page would be
enough, but I guess not for these non-SG NICs. We have to allocate
bigger chunks for them, so more fragmentation to handle.

Cheers,
Jarek P.