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Date: Tue, 1 Mar 2011 12:48:34 +0000
From: Stefan Hajnoczi <stefanha@linux.vnet.ibm.com>
Subject: Re: [Qemu-devel] [RFC][PATCH 0/2] Allow cache settings for block
	devices to be changed at runtime.
Message-ID: <20110301124834.GA10953@stefanha-thinkpad.localdomain>
References: <20110228171956.05a84fb9@zephyr> <4D6BBB72.6040205@redhat.com>
	<AANLkTim2iv4zAhLsC5XzhOX9o3bMVQ866O3z-ZAWG7r4@mail.gmail.com>
	<20110301124254.GA29485@lst.de>
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To: Christoph Hellwig <hch@lst.de>
Cc: Kevin Wolf <kwolf@redhat.com>, Anthony Liguori <aliguori@us.ibm.com>, Stefan Hajnoczi <stefanha@gmail.com>, qemu-devel <qemu-devel@nongnu.org>, Ananth Narayan <ananth@linux.vnet.ibm.com>, Prerna Saxena <prerna@linux.vnet.ibm.com>

On Tue, Mar 01, 2011 at 01:42:54PM +0100, Christoph Hellwig wrote:
> I have patches to do that, and to allow changing O_DIRECT via a monitor
> command, but to toggle O_SYNC via fcntl I first need to get a kernel
> patch in as that's currently not allowed to be changed at runtime.

Great it sounds like you have already implemented the two cases (guest wce and
host O_DIRECT) that we're talking about.

Stefan