[openib-general] [PATCH] [CMA] support for SDP + standard protocol

[Fab Tillier]

> From: Sean Hefty [mailto:sean.hefty at intel.com]
> Sent: Tuesday, December 13, 2005 10:39 AM
> 
> >I understand that SDP needs address translation services as well as
> >its own private data. However, I think it could be implemented using
> >optional API functions that allow the ULP to modify the private data
> >per its need, rather than adding ULP knowledge into CMA.
> >As example, if ISER spec will be modified, or some new ULP
> >implemented, that needed their own private data, we'll need to modify
> >CMA again, as well as creating a dependency between CMA versions and
> >ULPs.
> 
> The CMA must be aware of the format of the data in order to
> set and extract the IP addressing information.  SDP and the
> new CMA format locate these in different areas of the private
> data.  The CMA only defines the SDP hello header, and
> restricts its definition to the location of the IP addresses,
> source port, and version information.
> 
> If a ULP wants to define their own private data format and move
> the locations of any of those fields, then yes, the CMA would
> need to be changed again.  But I don't see how any API changes
> can prevent this, since the CMA must be able to extract the data
> on the remote side.

Now that the IB spec is going to have a section for how to support IP addressing
in CM MADs, there shouldn't be any need for a ULP to duplicate that
functionality.  SDP is a special case because it predates the IP addressing
extension to the CM protocol.

- Fab