Network device driver KPI/ABI and TOE

[gnn at freebsd.org]

At Sun, 6 Jan 2008 13:47:24 +0000 (GMT),
rwatson wrote:
> 
> 
> There's also the opportunity to think about whether it's possible to
> harden things in such a ways as to not give up our flexibility to
> keep maintaining and improving TCP (and other related subsystems),
> yet improving the quality of life for a third party TOE driver
> maintainer.  For example, might we provide accessor routines for
> certain data structures, or attempt to structure things to hide more
> of TCP locking from a TOE implementation?  Should we suggest that
> non-native TOE implementations rely less on our TCP code and provide
> there own where the hardware doesn't provide a complete
> implementation, in order to avoid building dependency on things that
> we know will change?
> 

Given the intimacy that I just perused in the code, basically the
driver knows a lot about internal TCP data structures, I think we need
to think about a kernel KPI just for these things. I'm not very happy
that there are things like cxgb_tcp_ctlinput() although I do know that
cleaning that kind of thing up and making a better KPI will be hard.

Best,
George