On Mar 11, 2005, at 9:37 AM, Matt Thomas wrote:

>> although it has another problem; IP_MAXPACKET, which is used to limit
>> largesend size, seems too large for rtl8169, which has only 64 tx 
>> descriptor.
>> i guess we need something like NDIS_TASK_TCP_LARGE_SEND.
>
> We could add a member to ifnet which contain the maximum multiplier of 
> MSS that could be offloaded.
>
>   len = (min(len, IP_MAXPACKET) / txsegsize) * txsegsize;
>
> would become:
>
>   len = min(len, IP_MAXPACKET) / txsegsize;
>   len = min(len, tp->t_inpcb->inp_route.ro_rt->rt_ifp->if_tsomaxseg);
>   len *= txsegsize;
>
> Does that make sense?

I don't think so.  It's not obvious to me how the packet-size-envening 
calculation has any correlation to the number of DMA segments.

-- thorpej