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[34.124.129.10]) by smtp.gmail.com with ESMTPSA id 41be03b00d2f7-ca5af7d58f3sm853302a12.1.2026.07.07.05.08.36 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Tue, 07 Jul 2026 05:08:38 -0700 (PDT) Date: Tue, 7 Jul 2026 12:08:27 +0000 From: Pranjal Shrivastava To: Christoph Hellwig Cc: Matthew Wilcox , Trond Myklebust , linux-nfs@vger.kernel.org, linux-kernel@vger.kernel.org, Anna Schumaker , Shivaji Kant , linux-mm@kvack.org, linux-fsdevel@vger.kernel.org Subject: Re: [PATCH v2 6/7] nfs: Optimize direct I/O to use folios for requests Message-ID: References: <20260616134000.2733403-1-praan@google.com> <20260616134000.2733403-7-praan@google.com> <7ee3bcfdd6126c93cbb1c219bf601182b95c10d9.camel@kernel.org> 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: On Fri, Jul 03, 2026 at 07:00:35AM -0700, Christoph Hellwig wrote: > On Fri, Jul 03, 2026 at 12:46:58PM +0000, Pranjal Shrivastava wrote: > > Do we have use-cases for a kernel user for direct I/O ? (Just curious to > > know if there's something on the horizon). > > Plenty. Basically any storage on file driver, or storage / file system > server: loop, zloop, nvmet, scsi target and nfsd ar the ones I know off > by head. > Ack. I see! Thanks! Regarding the page_folio impasse, how do you suggest we proceed? Should I expose and use get_contig_folio_len() from bvec? Or should I move the NFS helper into the iov_iter lib? (or both). Also, do you suggest sending the Folio move as a standalone patch if it is blocking the rest of the series or do we prefer keeping these in a single series? Thanks, Praan