Subject: Re: [RFC PATCH 08/11] IB/Verbs: Use management helper has_iwarp() for, iwarp-check

From: Michael Wang <[email-masked]>
Date: Tue, 31 Mar 2015 13:41:07 +0200

Hi, Tom

Thanks for the comments :-)

On 03/31/2015 01:19 PM, Tom Talpey wrote:
> [snip]
>
>>
>> Actually I'm thinking about Doug's idea to use rdma_transport_is_XX()
>> instead of the current basic helper, thus may be use rdma_transport_is_iwarp()
>> in here could be better, since it's actually a feature of iwarp tech
>> that RDMA Read only support one scatter-gather entry.
>
> No, you should expose an attribute to surface the maximum length of
> the remote gather list, which varies by adapter as well as protocol.
> The fact that iWARP is different from IB is not relevant, and conflates
> unrelated properties.

To be confirmed, so your point is that the max-read-sges will be different
even the transport is the same IWRAP, and that depends on the capability
of adapter, correct?

I currently only find this one place where infer max-read-sges from
transport type, it looks more like a special case to me rather than a generic
method we could exposed... and also  not very related with IB management
helper concept IMHO.

Regards,
Michael Wang