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[34.124.168.21]) by smtp.gmail.com with ESMTPSA id d9443c01a7336-2d14ccd8f1bsm41025825ad.25.2026.08.10.13.38.53 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Mon, 10 Aug 2026 13:38:55 -0700 (PDT) Date: Mon, 10 Aug 2026 20:38:49 +0000 From: Pranjal Shrivastava To: linux-nfs@vger.kernel.org, Trond Myklebust , Anna Schumaker Cc: Chuck Lever , Jeff Layton , linux-kernel@vger.kernel.org, Christoph Hellwig , Logan Gunthorpe , Jason Gunthorpe , linux-pci@vger.kernel.org, linux-rdma@vger.kernel.org, Shivaji Kant Subject: Re: [PATCH v4 0/5] nfs: modernize direct I/O path Message-ID: References: <20260810195040.2877784-1-praan@google.com> Precedence: bulk X-Mailing-List: linux-kernel@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: <20260810195040.2877784-1-praan@google.com> On Mon, Aug 10, 2026 at 07:50:34PM +0000, Pranjal Shrivastava wrote: > Modernize the NFS Direct I/O path as a preparatory step to enable PCI > Peer-to-Peer DMA (P2PDMA) support. Following feedback on the initial > RFC [1], the modernization and architectural changes are split into > different series. Additionally, based on the discussion in the v2 [2] > of this series, the migration of NFS Direct I/O to folios would be > handled in a separate follow-up series. > > Currently, NFS O_DIRECT relies on the legacy iov_iter_get_pages_alloc2() > API which does not support the pinning requirements for P2P memory. > The implementation moves NFS to the modern iov_iter_extract_pages() API. > [...] I'm calling out a few typos / non-code mistakes: 1. On the cover letter I missed updating the subject to v5 for this series (the changelog is noted below). 2. I also accidentally dropped Christoph's Reviewed-by tags on patches 1, 2, and 3 during the rebase (given while reviewing v4 [1]). Everything else in the series is correct as per the v5 changelog. Please let me know what the right etiquette is? Shall I resend the series? Apologies for the noise! > > [v5] > - Fixed an iov_iter_revert oops in nfs_direct_extract_pages(). > - Fixed a refcount underflow in nfs_direct_release_pages() during > swap-over-NFS by ensuring we do not call put_page() on unpinned memory. > - Rebased on fs-next > > [v4] > - https://lore.kernel.org/all/20260720150601.2702700-1-praan@google.com/ > - Dropped superfluous externs in include/linux/nfs_page.h > - Scoped `req` locally inside the loop in nfs_release_request_list() > - Wrapped >80 character lines in Patch 1 to adhere to coding style. > - Fixed typos and capitalization convention in the commit msgs > - Collected Reviewed-by tags from Christoph and Shivaji > - Rebased on fs-next > > [v3] > - https://lore.kernel.org/all/20260715143540.3597616-1-praan@google.com/ > - Dropped patches that added folio support for NFS Direct I/O > - Folded requested_bytes accounting in patch 5 due to dropped folio support > - Rebased on fs-next > > [v2] > - https://lore.kernel.org/all/20260616134000.2733403-1-praan@google.com/ > - Fix data corruption in nfs_direct_extract_pages() by correctly > calculating intra-page offsets using offset_in_page(). > - Fix requested_bytes accounting in direct read/write paths to only > increment after successful RPC scheduling. > - Add missing kernel-doc descriptions for the @pinned parameter in > nfs_page_create_from_page() and nfs_page_create_from_folio(). > - Rebase on fs-next/ > > [v1] https://lore.kernel.org/all/20260603053033.3300318-1-praan@google.com/ > > Pranjal Shrivastava (5): > nfs: make nfs_page pin-aware > nfs: track number of pinned pages in nfs_page > nfs: introduce nfs_release_request_list helper > nfs: migrate direct I/O to iov_iter_extract_pages > nfs: introduce nfs_direct_extract_pages helper > > fs/nfs/direct.c | 139 ++++++++++++++++++++------------------- > fs/nfs/pagelist.c | 62 ++++++++++++++--- > fs/nfs/read.c | 2 +- > fs/nfs/write.c | 2 +- > include/linux/nfs_page.h | 8 ++- > 5 files changed, 130 insertions(+), 83 deletions(-) > > > base-commit: 5b57716ed7ad2f4b1724461c8777015c4e4befb1 > -- > 2.55.0.679.g6767b8d81c-goog > Thanks, Praan [1] https://lore.kernel.org/all/20260720150601.2702700-1-praan@google.com/