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Date: Fri, 18 May 2018 19:08:12 +0200
From: Christoph Hellwig <hch@lst.de>
Subject: do we still need ->is_dirty_writeback
Message-ID: <20180518170812.GA5190@lst.de>
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To: Mel Gorman <mgorman@suse.de>, Trond Myklebust <trondmy@hammerspace.com>
Cc: linux-fsdevel@vger.kernel.org, linux-mm@kvack.org, linux-nfs@vger.kernel.org

Hi Mel,

you added the is_dirty_writeback callback a couple years ago mostly
to work around the crazy ext3 writeback code, which is long gone now.
We still use buffer_check_dirty_writeback on the block device, but
without that ext3 case we really should not need it anymore.

That leaves NFS, where I don't understand why it doesn't simply
use PageWrite?