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Date: Tue, 14 Nov 2023 17:57:14 +0000
From: Al Viro <viro@zeniv.linux.org.uk>
To: Christian Brauner <brauner@kernel.org>
Cc: Chuck Lever <cel@kernel.org>, akpm@linux-foundation.org,
	hughd@google.com, jlayton@redhat.com,
	Tavian Barnes <tavianator@tavianator.com>,
	Chuck Lever <chuck.lever@oracle.com>, linux-fsdevel@vger.kernel.org,
	linux-mm@kvack.org
Subject: Re: [PATCH RFC] libfs: getdents() should return 0 after reaching EOD
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References: <169997697704.4588.14555611205729567800.stgit@bazille.1015granger.net>
 <20231114-begleichen-miniatur-3c3a02862c4c@brauner>
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Sender: Al Viro <viro@ftp.linux.org.uk>

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.