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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> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: X-Rspamd-Queue-Id: E60C54000D X-Rspam-User: X-Stat-Signature: 7pz5imewfdw9whmojd3i4mrya8hsrytf X-Rspamd-Server: rspam03 X-HE-Tag: 1783426120-256803 X-HE-Meta: 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 7Nr9DNYh Y1II3BPuD0ISDRP4np/sM/k04Ovw61qoaiLbcOf3I1vOYcNTsi7MwdR25vesZlkVaH9K3H7I/1ygkx3RLe3FviyvRhAWSKLedyURAoK4mYhA8blzXX3Q07MDtlsFY0KxgAPGmlXqJu+cEv4LBNMOvzOYypwMUUQDxhAMuGirVBNEtzIsLp6Lzojii2MdCBUL72bN6SOLfFPhkALIKFWzfuQISjMujVe2ytO7jaPIhA5PCCL0GOKv8Dge3/haH2wWozBdzaDAFQHRBp3HBx0zhA/hoHpJiQhsWuLvV4iESmeHpvZtFHxz6pdyB5eJWd8+BhaylcwQQfSYifQ+hT5hk3or/SXb5lSdMXBI2aJK1kAx0WWY= Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: 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