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

Jason Gunthorpe
2009-10-09T00:33:03Z

On Fri, Oct 09, 2009 at 01:33:56AM +0200, Or Gerlitz wrote:

> However, I don't manage to follow on your port space discussion with
> Jason. Some apps may have client in user space and server in the
> kernel or vise versa. I wouldn't tie PS_IB or a like with ACM. The ACM
> ARP replacement protocol will reply only if the ip address specified
> in the broadcast request is an ip of this host on that pkey and a port
> connected to that fabric, correct?

The PS and sockaddr type are linked together, it makes no sense to use
a PS_TCP and a sockaddr_ib together - sockaddr_ib doesn't have a port
number, or IP address.

So AF_GID/IB must also use PS_IB.

The real complex question is if the scheme should have a transparent
way for something like rdma_get_addr_info to return a description that
uses PS_IB but sets things up to be compatible with a PS_TCP listener.

It would be easy to do this..

I really don't know, bypassing the IP stack so completely is really
not a great idea from an administration standpoint..

Jason