From 971a623b5bb048b3ecf079f4a761d423388ea59c Mon Sep 17 00:00:00 2001
From: John Snow <jsnow@redhat.com>
Date: Wed, 3 Apr 2019 18:18:54 +0200
Subject: [PATCH 149/163] block/dirty-bitmaps: disallow busy bitmaps as merge
 source

RH-Author: John Snow <jsnow@redhat.com>
Message-id: <20190403181857.9693-19-jsnow@redhat.com>
Patchwork-id: 85422
O-Subject: [RHEL-7.7 qemu-kvm-rhev PATCH 18/21] block/dirty-bitmaps: disallow busy bitmaps as merge source
Bugzilla: 1677073
RH-Acked-by: Max Reitz <mreitz@redhat.com>
RH-Acked-by: Stefan Hajnoczi <stefanha@redhat.com>
RH-Acked-by: Sergio Lopez Pascual <slp@redhat.com>

We didn't do any state checking on source bitmaps at all,
so this adds inconsistent and busy checks. readonly is
allowed, so you can still copy a readonly bitmap to a new
destination to use it for operations like drive-backup.

Signed-off-by: John Snow <jsnow@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Message-id: 20190301191545.8728-7-jsnow@redhat.com
Signed-off-by: John Snow <jsnow@redhat.com>
(cherry picked from commit cb8e58e3de1a0f39c60de272faa0133b98b02cb5)
Signed-off-by: John Snow <jsnow@redhat.com>
Signed-off-by: Miroslav Rezanina <mrezanin@redhat.com>
---
 block/dirty-bitmap.c | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/block/dirty-bitmap.c b/block/dirty-bitmap.c
index 6170f3a..2139354 100644
--- a/block/dirty-bitmap.c
+++ b/block/dirty-bitmap.c
@@ -825,6 +825,9 @@ void bdrv_merge_dirty_bitmap(BdrvDirtyBitmap *dest, const BdrvDirtyBitmap *src,
         goto out;
     }
 
+    if (bdrv_dirty_bitmap_check(src, BDRV_BITMAP_ALLOW_RO, errp)) {
+        goto out;
+    }
 
     if (!hbitmap_can_merge(dest->bitmap, src->bitmap)) {
         error_setg(errp, "Bitmaps are incompatible and can't be merged");
-- 
1.8.3.1