RE: [PATCH 2/2] rdma/cm: allow user to specify IP to DGID mapping

Sean Hefty
2009-10-22T19:14:03Z

>I really tried to follow the thread between you and Jason with quite
>little success, and I am going to give it more tries... in parallel,
>could you help me understand what is the --drive/reasoning-- from your
>perspective to add AF_IB / PS_IB here?

These are the things done today in the kernel wrt IB:

* Map a local or remote IP address to a GID.
* If a local address is not given, provide a usable address
based on the destination address.
* Acquire a path between the source and destination.
* Format the first 36 bytes of private data in the CM REQ.

Any or all of these could be done in user space instead. Adding AF_IB to the
kernel can provide a clean way of enabling this. It can also allow full support
of IB CM functionality through the RDMA CM interfaces.

- Sean