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[34.87.188.174]) by smtp.gmail.com with ESMTPSA id d9443c01a7336-2b2d4f0adbbsm158961075ad.46.2026.04.14.13.00.40 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Tue, 14 Apr 2026 13:00:43 -0700 (PDT) Date: Tue, 14 Apr 2026 20:00:37 +0000 From: Pranjal Shrivastava To: Christoph Hellwig Cc: trond.myklebust@hammerspace.com, anna@kernel.org, davem@davemloft.net, kuba@kernel.org, edumazet@google.com, pabeni@redhat.com, chuck.lever@oracle.com, jlayton@kernel.org, tom@talpey.com, okorniev@redhat.com, neil@brown.name, dai.ngo@oracle.com, linux-nfs@vger.kernel.org, netdev@vger.kernel.org Subject: Re: [RFC PATCH 4/4] nfs: allow P2PDMA in direct I/O path Message-ID: References: <20260401194501.2269200-1-praan@google.com> <20260401194501.2269200-5-praan@google.com> Precedence: bulk X-Mailing-List: linux-nfs@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: On Wed, Apr 01, 2026 at 10:05:36PM -0700, Christoph Hellwig wrote: > On Wed, Apr 01, 2026 at 07:45:00PM +0000, Pranjal Shrivastava wrote: > > Migrate the NFS Direct I/O path from the legacy iov_iter_get_pages_alloc2() > > API to the modern iov_iter_extract_pages() API. This migration enables > > support for PCI Peer-to-Peer DMA (P2PDMA) by allowing the setting the > > ITER_ALLOW_P2PDMA flag. > > > > Pass ITER_ALLOW_P2PDMA to iov_iter_extract_pages() only if the local > > mount indicates support via the NFS_CAP_P2PDMA capability bit (detected > > at mount time for RDMA transports). > > Please split theconversion to iov_iter_extract_pages into a separate > preparation patch, and even series. That is a long overdue change > that fixes potential data corruption in XFS. > Sure, I'll send out a series with the migration to iov_iter_extract_pages, should I club this with the pin-aware + folios for direct I/O or send it as a separate series? Thanks, Praan