[openib-general] RDMA connection and address translation API

[Christoph Hellwig]

On Wed, Aug 24, 2005 at 02:15:09PM -0700, Roland Dreier wrote:
>     Roland> Well, that's not what I would expect.  Suppose I have a
>     Roland> device configured with local addresses 192.168.11.12 and
>     Roland> 192.168.98.99 and I
> 
>     Christoph> You never configure a device with local addresses.  IP
>     Christoph> addresses are always a per-host attribute in Linux.
> 
> I don't think this is really true.  In some ways Linux behaves as if
> IP addresses are per-host (eg ARP responses can go out any interface)
> but really IP addresses are attached to an interface.  Every struct
> net_device has a struct in_device, and every struct in_device has a
> list of struct in_ifaddrs for the device's IP addresses.

This is correct, but the user-visible effect is what I said above.
When you do an ARP query for any of the IP addresses of a linux box
you'll get a responce even if that interface isn't on the network.

Even if you don't think that's enough you can assign any number of
IP and other networking addresses to a given device even formally,
rendering the notation of an IP address <-> network device relation
rather mood.