Enabling bitmap successor is necessary to enable successors of bitmaps
being migrated before target vm start.

Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Reviewed-by: John Snow <jsnow@redhat.com>
Reviewed-by: Fam Zheng <famz@redhat.com>
Message-id: 20180207155837.92351-2-vsementsov@virtuozzo.com
Signed-off-by: John Snow <jsnow@redhat.com>
---
 include/block/dirty-bitmap.h | 1 +
 block/dirty-bitmap.c         | 8 ++++++++
 2 files changed, 9 insertions(+)

diff --git a/include/block/dirty-bitmap.h b/include/block/dirty-bitmap.h
index 09efec609f..e0ebc96b01 100644
--- a/include/block/dirty-bitmap.h
+++ b/include/block/dirty-bitmap.h
@@ -21,6 +21,7 @@ BdrvDirtyBitmap *bdrv_dirty_bitmap_abdicate(BlockDriverState *bs,
 BdrvDirtyBitmap *bdrv_reclaim_dirty_bitmap(BlockDriverState *bs,
                                            BdrvDirtyBitmap *bitmap,
                                            Error **errp);
+void bdrv_dirty_bitmap_enable_successor(BdrvDirtyBitmap *bitmap);
 BdrvDirtyBitmap *bdrv_find_dirty_bitmap(BlockDriverState *bs,
                                         const char *name);
 void bdrv_dirty_bitmap_make_anon(BdrvDirtyBitmap *bitmap);
diff --git a/block/dirty-bitmap.c b/block/dirty-bitmap.c
index 909f0517f8..0d0e807216 100644
--- a/block/dirty-bitmap.c
+++ b/block/dirty-bitmap.c
@@ -234,6 +234,14 @@ int bdrv_dirty_bitmap_create_successor(BlockDriverState *bs,
     return 0;
 }
 
+/* Called with BQL taken. */
+void bdrv_dirty_bitmap_enable_successor(BdrvDirtyBitmap *bitmap)
+{
+    qemu_mutex_lock(bitmap->mutex);
+    bdrv_enable_dirty_bitmap(bitmap->successor);
+    qemu_mutex_unlock(bitmap->mutex);
+}
+
 /**
  * For a bitmap with a successor, yield our name to the successor,
  * delete the old bitmap, and return a handle to the new bitmap.
-- 
2.11.1