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Date:   Thu, 6 Oct 2022 01:33:34 -0700
From:   Christoph Hellwig <hch@infradead.org>
To:     Daeho Jeong <daeho43@gmail.com>,
        "Darrick J. Wong" <djwong@kernel.org>
Cc:     linux-kernel@vger.kernel.org,
        linux-f2fs-devel@lists.sourceforge.net, kernel-team@android.com,
        Daeho Jeong <daehojeong@google.com>,
        linux-fsdevel@vger.kernel.org
Subject: Re: [PATCH v4 2/2] f2fs: introduce F2FS_IOC_START_ATOMIC_REPLACE
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On Tue, Oct 04, 2022 at 10:13:51AM -0700, Daeho Jeong wrote:
> From: Daeho Jeong <daehojeong@google.com>
> 
> introduce a new ioctl to replace the whole content of a file atomically,
> which means it induces truncate and content update at the same time.
> We can start it with F2FS_IOC_START_ATOMIC_REPLACE and complete it with
> F2FS_IOC_COMMIT_ATOMIC_WRITE. Or abort it with
> F2FS_IOC_ABORT_ATOMIC_WRITE.

It would be great to Cc Darrick and linux-fsdevel as there have been
attempts to do this properly at the VFS level instead of a completely
undocumented ioctl.