From mboxrd@z Thu Jan  1 00:00:00 1970
From: Matthew Wilcox <willy@infradead.org>
Date: Mon, 13 Jul 2020 12:55:09 +0100
Subject: [Cluster-devel] [PATCH 2/2] iomap: fall back to buffered writes
 for invalidation failures
In-Reply-To: <20200713074633.875946-3-hch@lst.de>
References: <20200713074633.875946-1-hch@lst.de>
	<20200713074633.875946-3-hch@lst.de>
Message-ID: <20200713115509.GW12769@casper.infradead.org>
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On Mon, Jul 13, 2020 at 09:46:33AM +0200, Christoph Hellwig wrote:
> Failing to invalid the page cache means data in incoherent, which is
> a very bad state for the system.  Always fall back to buffered I/O
> through the page cache if we can't invalidate mappings.

Is that the right approach though?  I don't have a full picture in my head,
but wouldn't we be better off marking these pages as !Uptodate and doing
the direct I/O?