Message-ID: <55280D51.20402@talpey.com>
Date: Fri, 10 Apr 2015 13:50:09 -0400
From: Tom Talpey <tom@talpey.com>
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To: Doug Ledford <dledford@redhat.com>, "ira.weiny" <ira.weiny@intel.com>
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Subject: Re: [PATCH v2 01/17] IB/Verbs: Implement new callback query_transport()
 for each HW
References: <5523CCD5.6030401@profitbricks.com>	 <5523D098.3020007@profitbricks.com> <1428517786.2980.180.camel@redhat.com>	 <20150410074805.GA11855@phlsvsds.ph.intel.com> <1428685843.2980.353.camel@redhat.com>
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Sender: linux-nfs-owner@vger.kernel.org

On 4/10/2015 1:10 PM, Doug Ledford wrote:
> As per my above statement, rdma_transport* tests were testing the high
> level transport type, rdma_port* types were testing link layers.  iWARP
> has an Eth link layer, so technically port_is_iwarp makes no sense.  But
> since all the other types had a check too, I included port_is_iwarp just
> to be complete, and if you are going to ask if a specific port is iwarp
> as a link layer, it makes sense to say yes if the transport is iwarp,
> not if the link layer is eth.

Not wanting to split hairs, but I would not rule out the possibility
of a future device supporting iWARP on one port and another RDMA
protocol on another. One could also imagine softiWARP and softROCE
co-existing atop a single ethernet NIC.

So, I disagree that port_is_iwarp() is a nonsequitur.

Tom.