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c=relaxed/relaxed; d=hostedemail.com; s=arc-20220608; t=1771397264; h=from:from:sender:reply-to:subject:subject:date:date: message-id:message-id:to:to:cc:cc:mime-version:mime-version: content-type:content-type:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=IeUO3hAFBv9RuKSTC7vFCIY9WhPjcg+tq37dXzRft+Y=; b=uxlkf8uooIoMNiZHCXWTchY4pRAxpFpdaal43fMKv60y0DIGOEhjzg0ZDcM6eHcGr+SWsU Wq5i4Lk9hTfDRV26OuznvQNqsiktjvwfbFTWczrBpuQCGhFlTXtzwZSoQ2R2BUUB75FmaP 6+KRo2zPFdRJKqjODOiHDN38mJ/TcnE= Received: by verein.lst.de (Postfix, from userid 2407) id 664F568B05; Wed, 18 Feb 2026 07:47:39 +0100 (CET) Date: Wed, 18 Feb 2026 07:47:39 +0100 From: Christoph Hellwig To: Dave Chinner Cc: Andres Freund , Pankaj Raghav , Jan Kara , Ojaswin Mujoo , linux-xfs@vger.kernel.org, linux-mm@kvack.org, linux-fsdevel@vger.kernel.org, lsf-pc@lists.linux-foundation.org, djwong@kernel.org, john.g.garry@oracle.com, willy@infradead.org, hch@lst.de, ritesh.list@gmail.com, Luis Chamberlain , dchinner@redhat.com, Javier Gonzalez , gost.dev@samsung.com, tytso@mit.edu, p.raghav@samsung.com, vi.shah@samsung.com Subject: Re: [LSF/MM/BPF TOPIC] Buffered atomic writes Message-ID: <20260218064739.GA8881@lst.de> References: <7cf3f249-453d-423a-91d1-dfb45c474b78@linux.dev> <4627056f-2ab9-4ff1-bca0-5d80f8f0bbab@linux.dev> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.5.17 (2007-11-01) X-Stat-Signature: 6d8gkufuc5xid7ac1ra75br3opjdog6e X-Rspam-User: X-Rspamd-Server: rspam08 X-Rspamd-Queue-Id: D0127A000D X-HE-Tag: 1771397263-211983 X-HE-Meta: U2FsdGVkX1+yT5qNkBck3Y9WhHNSZ8MQ/hy2jbg8wy2l6qKV6m4HT6NLQLWHhc6zNaQDWOlOzg9Se49909l69H6fDxvjk1H5WmA/bu96SwK7FgAIbq5gJnayFQSzhgF55ztXT1lm2gOGF7qYLcdLF/cuhJA7RM9Jub84sNBwxI/DfDofADQ+c7n2gonTDaDFX8hffkVPUC/k/O5DYU54QBc+Sjr2TeL/B0kwArSr4H//3VOiThhI0YGAERO83EPeHKP5WoAsJIpd82r+H/goBxBQeXxj+QdPxeIC0k9xDLIkVj2R33P+v30btEXAK93Sue5dQSVpC+Q1f2gaLGuf9KY3YTIOCzRaQEh2YbjzR9k2IyOJsZqtOyFTSBBQkOW0ex5CLaI3B21JoE7T9kWN1F33SqhT1c6C9fEi/KVm3cvZ1AWrO1sIvxDZivMBh1zR65Uhr5jrcOuL0CeFsA1j7Jx+O7cfYOBO9QMu+yiSxe6+adHPEMrCEJjB3D898uZZgp+Sa57Dn7OnXNLEoF3pGUb6iU1Lgz1xBwqYBGueOBIVMbMCg0YjWTmiigyD2AkkEk69iDXggldekfdHoViDuMhME3EGDuw/CgQsvQh+OyaYPhhp1mQLaMhG6CcB2CgvGKC84Z25fgB/er08YV/Q5wRwrCZsmDVCpuCL1S4Elo/00Gq3EQ1lUg0JnLgvedCrNEbn7lryGrXFiE7xrfbdRH0wp5E/sHVNwH51Wh6VmqFnS7f7AitllhHekzAvZkPHZe45mny0AXRAqVB/TqzzHWxzYn/7PfrIzqMjyPINQvNdd2PjdtmaJDhmg9NBQijOTuS90K3KDLYbQmX6GgxOb7EN2bFeqD1mZP2qiwCUJVBx4eky7H58m/3mxcOoQUbtSkrr6wSt5PJKgWMrQi0Cqx7LuyGDgzh2Zy7kr7e9S6AxX0QWQ/ZhTf1XqShyujufmsMaM5qcVipNIAu2yTH HecjpqyI dXBKRRsgqrf/wWft4VKN/7+TWw+YLrBEt+AqYejQ7xP3c48/97ehbn+p6Fu54t+tdS3ta/hd/dnftciXgtgewIh4mfOIIQgKrBsJu8EwpFGhLRuWg9e0reVLDuKP/GaK3/op8xF1981xtCZAV/SRNBMs6GCCV09LUMqIr+d4YeRERyHs= X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: On Wed, Feb 18, 2026 at 12:04:43PM +1100, Dave Chinner wrote: > > > > I'd call it RWF_WRITETHROUGH but otherwise it makes sense. > > > > > > > > > > One naive question: semantically what will be the difference between > > > RWF_DSYNC and RWF_WRITETHROUGH? > > None, except that RWF_DSYNC provides data integrity guarantees. Which boils down to RWF_DSYNC still writing out the inode and flushing the cache. > > Which > > wouldn't be needed for RWF_WRITETHROUGH, right? > > Correct, there shouldn't be any data integrity guarantees associated > with plain RWF_WRITETHROUGH. Which makes me curious if the plain RWF_WRITETHROUGH would be all that useful.