Subject: Re: [PATCH V3 1/5] RDMA/core: Transport-independent access flags
To: Christoph Hellwig <hch@infradead.org>
References: <20150705231831.12029.80307.stgit@build2.ogc.int>
 <20150705232158.12029.25472.stgit@build2.ogc.int>
 <559A340E.9000000@dev.mellanox.co.il>
 <001601d0b7f9$3e1d6d40$ba5847c0$@opengridcomputing.com>
 <559AAA22.1000608@dev.mellanox.co.il> <20150707090001.GB11736@infradead.org>
Cc: Steve Wise <swise@opengridcomputing.com>, dledford@redhat.com,
        sagig@mellanox.com, ogerlitz@mellanox.com, roid@mellanox.com,
        linux-rdma@vger.kernel.org, eli@mellanox.com,
        target-devel@vger.kernel.org, linux-nfs@vger.kernel.org,
        trond.myklebust@primarydata.com, bfields@fieldses.org
From: Sagi Grimberg <sagig@dev.mellanox.co.il>
Message-ID: <559B9891.8060907@dev.mellanox.co.il>
Date: Tue, 7 Jul 2015 12:14:57 +0300
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Sender: linux-nfs-owner@vger.kernel.org

On 7/7/2015 12:00 PM, Christoph Hellwig wrote:
> On Mon, Jul 06, 2015 at 07:17:38PM +0300, Sagi Grimberg wrote:
>>> Ok. I'll remove all uses of ib_get_dma_mr()...
>>>
>>>
>>
>> I meant that rdma_get_dma_mr can go away. I'd prefer to get the
>> needed access_flags and just call existing verb.
>
> I strongly disagree.  As this series has shown the existing API is not
> epressive enough for all transports.  It thus needs to go away and be
> fully replaced by the new API introduced here.
>

Christoph,

I wasn't arguing about having a transport independent API. I was
referring to this wrapper specifically that trampolines to
ib_get_dma_mr() with rdma_device_access_flags(pd, roles, attrs) helper.

The rdma_device_access_flags() itself is fine. However, given that
this helper is used elsewhere as well, I don't see the point of having
yet another helper specifically just for the dma_mr case that does
nothing more than trampolines with a call to rdma_device_access_flags().

Sagi.