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From:   Steve French <smfrench@gmail.com>
Date:   Wed, 23 Feb 2022 23:30:07 -0600
Message-ID: <CAH2r5mv7Z7XmyWgp5K8ZshA1OiMBTNGU-v8FdmwwkZaNNe=4wA@mail.gmail.com>
Subject: [LSF/MM/BPF TOPIC] making O_TMPFILE more atomic
To:     lsf-pc@lists.linux-foundation.org,
        linux-fsdevel <linux-fsdevel@vger.kernel.org>
Cc:     LKML <linux-kernel@vger.kernel.org>
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Currently creating tmpfiles on Linux can be problematic because the
tmpfile is not created and opened at the same time  (vfs_tmpfile calls
into the fs, then later vfs_open is called to open the tmpfile).   For
some filesystems it would be more natural to create and open the
tmpfile as one operation (because the action of creating the file on
some filesystems returns an open handle, so closing it then reopening
it would cause the tmpfile to be deleted).

I would like to discuss whether the function do_tmpfile (which creates
and then opens the tmpfile) could have an option for a filesystem to
do this as one operation which would allow it to be more atomic and
allow it to work on a wider variety of filesystems.

-- 
Thanks,

Steve