From mboxrd@z Thu Jan  1 00:00:00 1970
From: Samuel Thibault <samuel.thibault@eu.citrix.com>
Subject: [PATCH] stubdom: fix read-only disks access
Date: Fri, 1 Aug 2008 19:17:50 +0100
Message-ID: <20080801181750.GF4553@implementation.uk.xensource.com>
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stubdom: fix read-only disks access

There is no need for a flush on read-only disks.  It would actually even
error out and disturb the guest.

Signed-off-by: Samuel Thibault <samuel.thibault@eu.citrix.com>

diff -r 3dedb6209991 tools/ioemu/block-vbd.c
--- a/tools/ioemu/block-vbd.c	Fri Aug 01 12:18:02 2008 +0100
+++ b/tools/ioemu/block-vbd.c	Fri Aug 01 19:16:52 2008 +0100
@@ -273,6 +273,10 @@ static BlockDriverAIOCB *vbd_aio_flush(B
     BDRVVbdState *s = bs->opaque;
     VbdAIOCB *acb = NULL;
 
+    if (s->info.mode == O_RDONLY) {
+        cb(opaque, 0);
+        return NULL;
+    }
     if (s->info.barrier == 1) {
         acb = vbd_aio_setup(bs, 0, NULL, 0,
                 s->info.flush == 1 ? vbd_nop_cb : cb, opaque);