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Received: from viro by zeniv.linux.org.uk with local (Exim 4.96 #2 (Red Hat Linux)) id 1r2xf0-00FlkJ-2v; Tue, 14 Nov 2023 17:57:15 +0000 Date: Tue, 14 Nov 2023 17:57:14 +0000 From: Al Viro To: Christian Brauner Cc: Chuck Lever , akpm@linux-foundation.org, hughd@google.com, jlayton@redhat.com, Tavian Barnes , Chuck Lever , linux-fsdevel@vger.kernel.org, linux-mm@kvack.org Subject: Re: [PATCH RFC] libfs: getdents() should return 0 after reaching EOD Message-ID: <20231114175714.GT1957730@ZenIV> References: <169997697704.4588.14555611205729567800.stgit@bazille.1015granger.net> <20231114-begleichen-miniatur-3c3a02862c4c@brauner> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20231114-begleichen-miniatur-3c3a02862c4c@brauner> X-Stat-Signature: uup9xwgnintqx1dfohctewaxkfns9b6i X-Rspamd-Server: rspam10 X-Rspamd-Queue-Id: 9DE878001F X-Rspam-User: X-HE-Tag: 1699984649-988428 X-HE-Meta: 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 qGYhd42s TTLoVhs8ZLLGr7zoy/73ElaimjYHR9aTBHKQp6igj/tw0iDy3Y7vMZ0IosHkektzxG/v2eMcTOxuiaPUcZHr9T9YlyzAMdg+AVYh/zp7AJBQvbXnoQjU7ScDk1Qb/Zgvmgk+oZMMcV//Bt0gbEK8EwG5vwPzfs5oAG+3oIPlKvMFJLdjTHXEsCxXdT1W2IYcECMFoSfULDb88+nvzx/FKxN2b21lgaU/dEgCwh92K+BSvrw4wS50RkyHC1hanU4RfNSZVIbJ5kkoOpUw+uPj4WJ7snOHCjqTjbHnAJkeNKDAY50vak0Q4DomMQCHA8HwgKqH97lWSmUjqqKrbyrENwmZqAEetmSx3tASgd6FW1OaLb5Awt4cf9IEjAQ== X-Bogosity: Ham, tests=bogofilter, spamicity=0.075701, 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 Tue, Nov 14, 2023 at 06:29:15PM +0100, Christian Brauner wrote: > I think it's usually best practice to only modify the file->private_data > pointer during f_op->open and f_op->close but not override > file->private_data once the file is visible to other threads. I think > here it might not matter because access to file->private_data is > serialized on f_pos_lock and it's not used by anything else. That is entirely up to filesystem. Warning that use of that library helper means that you can't use your ->d_fsdata for anything else - sure, but that's it.