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Date:   Thu, 5 Aug 2021 19:24:28 +0100
From:   Matthew Wilcox <willy@infradead.org>
To:     "Darrick J. Wong" <djwong@kernel.org>
Cc:     linux-xfs@vger.kernel.org, linux-fsdevel@vger.kernel.org,
        Alexander Viro <viro@zeniv.linux.org.uk>,
        Thomas Gleixner <tglx@linutronix.de>
Subject: Re: [PATCH 1/2] iomap: Use kmap_local_page instead of kmap_atomic
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On Thu, Aug 05, 2021 at 10:39:03AM -0700, Darrick J. Wong wrote:
> Though now that I think about it: Why does iomap_write_actor still use
> copy_page_from_iter_atomic?  Can that be converted to use regular
> copy_page_from_iter, which at least sometimes uses kmap_local_page?

I suspect copy_page_from_iter_atomic() should be converted to use
kmap_local_page(), but I don't know.  generic_perform_write() uses
the _atomic() version, so I'm not doing anything different without
understanding more than I currently do.