[openib-general] Re: [RFC] IB address translation using ARP

[Sean Hefty]

>I suspect the CM related part cant be easily shared between SDP and CMA,
>since the CM REQ format and the service record format for SDP are already
>set in stone, and are very SDP-specific.

I've given this some more thought, and I think that it makes sense for the CMA
to provide support for SDP, iSER, kDAPL, etc. to the extent that it can.  This
requires the CMA to:

* send CM REQ private data using different formats
* know how to interpret received CM REQ private data
* map listen requests to service IDs correctly

One solution is to make the CMA protocol aware to some degree.  Clients can
specify a protocol when binding a cma_id to a particular address.

In the simplest case, a user can tell the CMA to simply pass through all private
data.  On the passive side, this means that the CMA does not provide source
address information.  Apps must either extract the source information from the
private data themselves, or through some other means, such as ATS.

However, this doesn't help map connection or listen requests to IB service IDs.
And I'm not familiar with how SDP, iSER, kDAPL perform their mappings to know if
the CMA could do this without knowing being protocol aware.  If this is the
case, then it makes sense to give the CMA some knowledge of the CM REQ private
data format.

- Sean