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To:     Christoph Hellwig <hch@lst.de>
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References: <20201106170036.18713-1-logang@deltatee.com>
 <20201106170036.18713-5-logang@deltatee.com> <20201109091258.GB28918@lst.de>
From:   Logan Gunthorpe <logang@deltatee.com>
Message-ID: <4e336c7e-207b-31fa-806e-c4e8028524a5@deltatee.com>
Date:   Mon, 9 Nov 2020 09:47:11 -0700
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Subject: Re: [RFC PATCH 04/15] lib/scatterlist: Add flag for indicating P2PDMA
 segments in an SGL
Precedence: bulk


On 2020-11-09 2:12 a.m., Christoph Hellwig wrote:
> On Fri, Nov 06, 2020 at 10:00:25AM -0700, Logan Gunthorpe wrote:
>> We make use of the top bit of the dma_length to indicate a P2PDMA
>> segment.
> 
> I don't think "we" can.  There is nothing limiting the size of a SGL
> segment.

Yes, I expected this would be the unacceptable part. Any alternative ideas?

Logan