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Received: from guinness.priv.deltatee.com ([172.16.1.162]) by ale.deltatee.com with esmtp (Exim 4.92) (envelope-from ) id 1kcAK2-00011d-Rd; Mon, 09 Nov 2020 09:47:15 -0700 To: Christoph Hellwig References: <20201106170036.18713-1-logang@deltatee.com> <20201106170036.18713-5-logang@deltatee.com> <20201109091258.GB28918@lst.de> From: Logan Gunthorpe Message-ID: <4e336c7e-207b-31fa-806e-c4e8028524a5@deltatee.com> Date: Mon, 9 Nov 2020 09:47:11 -0700 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:78.0) Gecko/20100101 Thunderbird/78.3.1 MIME-Version: 1.0 In-Reply-To: <20201109091258.GB28918@lst.de> Content-Language: en-CA X-SA-Exim-Connect-IP: 172.16.1.162 X-SA-Exim-Rcpt-To: daniel.vetter@ffwll.ch, willy@infradead.org, ddutile@redhat.com, jhubbard@nvidia.com, iweiny@intel.com, christian.koenig@amd.com, jgg@ziepe.ca, dan.j.williams@intel.com, sbates@raithlin.com, iommu@lists.linux-foundation.org, linux-mm@kvack.org, linux-pci@vger.kernel.org, linux-block@vger.kernel.org, linux-nvme@lists.infradead.org, linux-kernel@vger.kernel.org, hch@lst.de X-SA-Exim-Mail-From: logang@deltatee.com Subject: Re: [RFC PATCH 04/15] lib/scatterlist: Add flag for indicating P2PDMA segments in an SGL X-SA-Exim-Version: 4.2.1 (built Wed, 08 May 2019 21:11:16 +0000) X-SA-Exim-Scanned: Yes (on ale.deltatee.com) X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20201109_114723_745374_9D77E4A6 X-CRM114-Status: GOOD ( 12.85 ) X-BeenThere: linux-nvme@lists.infradead.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Jason Gunthorpe , linux-pci@vger.kernel.org, Daniel Vetter , Ira Weiny , linux-kernel@vger.kernel.org, linux-nvme@lists.infradead.org, Stephen Bates , linux-block@vger.kernel.org, linux-mm@kvack.org, iommu@lists.linux-foundation.org, Don Dutile , Matthew Wilcox , John Hubbard , Dan Williams , =?UTF-8?Q?Christian_K=c3=b6nig?= Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "Linux-nvme" Errors-To: linux-nvme-bounces+linux-nvme=archiver.kernel.org@lists.infradead.org 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 _______________________________________________ Linux-nvme mailing list Linux-nvme@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-nvme