[ofa-general] [PATCH] use LIDs from REQ LRH for inter-subnet connections

[Sean Hefty]

> When you get a chance, can you try out this patch?  I tested that it worked
> for a local subnet connection by commenting out the hop_limit check.  So,
> I'm interested to know if you run into any problems.  If you do run into
> issues, madeye may be able to help.

I've reworked this patch, and added a couple more based on 2.6.21-rc4.  The 
patches are available from

	git://git.openfabrics.org/~shefty/rdma-dev.git ib_router

I started to put checks to validate the CM REQ data against the received LRH 
data, but dropped them.

A couple of other notes:

* If the LID in the CM REQ is permissive, then the LID/SL data from the LRH is 
used instead.  The user of the ib_cm is responsible for setting the LID to 
permissive to control this, which should allow this functionality to work 
alongside the more general ib_remote_sa type of solution.

* The CM architecture allows for primary and alternate paths where one is subnet 
local, and the other is routed.  I don't think anything breaks this at the 
moment, and I believe that the changes to the ib_cm to support routing are done. 
  (Support for non-reversible paths is still missing.)

I'm still developing the ib_remote_sa solution.  All of my testing done so far 
is limited to a single subnet, with hacks thrown into the code to force 
execution of the new code paths.

- Sean