From mboxrd@z Thu Jan  1 00:00:00 1970
From: Alasdair G Kergon <agk@redhat.com>
Subject: Re: Re: [RFD] BIO_RW_BARRIER - what it means for devices,
	filesystems, and dm/md.
Date: Thu, 31 May 2007 01:57:37 +0100
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Cc: Tejun Heo <htejun@gmail.com>, David Chinner <dgc@sgi.com>,
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On Thu, May 31, 2007 at 10:46:04AM +1000, Neil Brown wrote:
> What if the truth changes (as can happen with md or dm)?

You get notified in endio() that the barrier had to be emulated?
 
Alasdair
-- 
agk@redhat.com