Re: [PATCH v2] RDMA/CMA: fix iWARP adapter TCP port space usage

Roland Dreier
2010-06-23T18:28:03Z

> Roland, do you think the iSCSI approach is a "good design" for iWARP
> devices?

Well, it's a different problem since as I said the port collision
problem is a non-issue for iSCSI anyway. But yes having a separate
interface to assign an iWARP IP address to an RNIC does seem to avoid
the immediate problem.

I actually don't know what the right answer is -- having a separate IP
address for iWARP does seem to lead to having to duplicate everything
for configuring it. (And this is the approach for the cxgb[34] iSCSI
drivers, right?)

On the other hand trying to hook offloaded iWARP into the normal stack
does seem to lead to a mess. I see DaveM's point: TCP port space is
just the beginning -- filtering, queueing, etc also have config that
ultimately an offload device would want to hook too.

Maybe the sanest out of a bad set of options would be to come up with a
standard way to configure independent TCP/IP stacks that share a link.

really, dunno.

- R.
--
Roland Dreier <rolandd-FYB4Gu1CFyUAvxtiuMwx3w@public.gmane.org> || For corporate legal information go to: