From 2afae8c7d44a043e36038d5f6f600034ad2b2aca Mon Sep 17 00:00:00 2001
From: Kevin Shanahan <kmshanah@disenchant.net>
Date: Fri, 21 Sep 2012 08:50:22 +0930
Subject: [PATCH] blockdev: preserve readonly and snapshot states across media
 changes

If readonly=on is given at device creation time, the ->readonly flag
needs to be set in the block driver state for this device so that
readonly-ness is preserved across media changes (qmp change command).
Similarly, to preserve the snapshot property requires ->open_flags to
be correct.

Signed-off-by: Kevin Shanahan <kmshanah@disenchant.net>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
(cherry picked from commit 80dd1aae3657a902d262f5d20a7a3c655b23705e)

Signed-off-by: Michael Roth <mdroth@linux.vnet.ibm.com>
---
 blockdev.c | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/blockdev.c b/blockdev.c
index 4a5266e..9ba3503 100644
--- a/blockdev.c
+++ b/blockdev.c
@@ -533,6 +533,8 @@ DriveInfo *drive_init(QemuOpts *opts, int default_to_scsi)
                      if_name[type], mediastr, unit_id);
     }
     dinfo->bdrv = bdrv_new(dinfo->id);
+    dinfo->bdrv->open_flags = snapshot ? BDRV_O_SNAPSHOT : 0;
+    dinfo->bdrv->read_only = ro;
     dinfo->devaddr = devaddr;
     dinfo->type = type;
     dinfo->bus = bus_id;
-- 
1.8.0.2