From mboxrd@z Thu Jan  1 00:00:00 1970
From: Samuel Thibault <samuel.thibault@eu.citrix.com>
Subject: Block WRITE_BARRIER / FLUSH_DISKCACHE operations and
	parameters
Date: Thu, 7 Feb 2008 16:14:42 +0000
Message-ID: <20080207161442.GJ4310@implementation.uk.xensource.com>
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Hello,

Nothing is said about parameters to be given along WRITE_BARRIER or
FLUSH_DISKCACHE operations.  I guess they are both implicitely supposed
to be write operations? (it's the case for WRITE_BARRIER in the Linux
implementation) If so, would it be fine to allow nr_segments to be 0?
As part of IDE cache flush emulation, I need to issue WRITE_BARRIERs
without issuing any actual write...

Samuel