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Subject: Re: [PATCH 00/16] Add new DMA mapping operation for P2PDMA
To:     Jason Gunthorpe <jgg@ziepe.ca>,
        Logan Gunthorpe <logang@deltatee.com>
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 <20210427192838.GP2047089@ziepe.ca>
From:   John Hubbard <jhubbard@nvidia.com>
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Date:   Tue, 27 Apr 2021 13:21:50 -0700
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On 4/27/21 12:28 PM, Jason Gunthorpe wrote:
> On Thu, Apr 08, 2021 at 11:01:07AM -0600, Logan Gunthorpe wrote:
>> Hi,
>>
>> This patchset continues my work to to add P2PDMA support to the common
>> dma map operations. This allows for creating SGLs that have both P2PDMA
>> and regular pages which is a necessary step to allowing P2PDMA pages in
>> userspace.
>>
>> The earlier RFC[1] generated a lot of great feedback and I heard no show
>> stopping objections. Thus, I've incorporated all the feedback and have
>> decided to post this as a proper patch series with hopes of eventually
>> getting it in mainline.
>>
>> I'm happy to do a few more passes if anyone has any further feedback
>> or better ideas.
> 
> For the user of the DMA API the idea seems reasonable enough, the next
> steps to integrate with pin_user_pages() seem fairly straightfoward
> too
> 
> Was there no feedback on this at all?
> 

oops, I meant to review this a lot sooner, because this whole p2pdma thing is
actually very interesting and important...somehow it slipped but I'll take
a look now.

thanks,
-- 
John Hubbard
NVIDIA