From mboxrd@z Thu Jan  1 00:00:00 1970
From: Michael Wang <yun.wang-EIkl63zCoXaH+58JC4qpiA@public.gmane.org>
Subject: Re: [RFC PATCH 08/11] IB/Verbs: Use management helper has_iwarp()
 for, iwarp-check
Date: Tue, 31 Mar 2015 09:39:16 +0200
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List-Id: linux-rdma@vger.kernel.org

On 03/31/2015 12:35 AM, Jason Gunthorpe wrote:
> On Mon, Mar 30, 2015 at 05:10:12PM +0200, Michael Wang wrote:
>> I found that actually we don't have to touch this one which
>> only used by HW driver currently.
> I'm having a hard time understanding this, the code in question was in
>
> net/sunrpc/xprtrdma/svc_rdma_recvfrom.c
>
> Which is the NFS ULP, not a device driver.

I'm not familiar with this part too :-P but yes, it looks like an ulp
to support NFS.

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.

But I need more investigation on that idea, there are some part
especially inside device driver I'm not very clear, things could be more
easier if the semantic there is compatible with Doug's proposal ;-)

Regards,
Michael Wang

>
> Regards,
> Jason

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