[Qemu-block] [PATCH v7 07/16] block/dirty-bitmap: add bdrv_dirty_bitmap_release_successor

[Vladimir Sementsov-Ogievskiy]

To just release successor and unfreeze bitmap without any additional
work.

Signed-off-by: Vladimir Sementsov-Ogievskiy <vsement...@virtuozzo.com>
Signed-off-by: Denis V. Lunev <d...@openvz.org>
---
 block/dirty-bitmap.c         | 13 +++++++++++++
 include/block/dirty-bitmap.h |  2 ++
 2 files changed, 15 insertions(+)

diff --git a/block/dirty-bitmap.c b/block/dirty-bitmap.c
index 7b598c36bf..b5678d2d25 100644
--- a/block/dirty-bitmap.c
+++ b/block/dirty-bitmap.c
@@ -303,6 +303,19 @@ BdrvDirtyBitmap 
*bdrv_reclaim_dirty_bitmap(BlockDriverState *bs,
     return parent;
 }
 
+/* Called with BQL taken. */
+void bdrv_dirty_bitmap_release_successor(BlockDriverState *bs,
+                                         BdrvDirtyBitmap *parent)
+{
+    qemu_mutex_lock(parent->mutex);
+
+    if (parent->successor) {
+        bdrv_release_dirty_bitmap(bs, parent->successor);
+        parent->successor = NULL;
+    }
+
+    qemu_mutex_unlock(parent->mutex);
+}
 /**
  * Truncates _all_ bitmaps attached to a BDS.
  * Called with BQL taken.
diff --git a/include/block/dirty-bitmap.h b/include/block/dirty-bitmap.h
index d00a7a4b7c..fa2f670050 100644
--- a/include/block/dirty-bitmap.h
+++ b/include/block/dirty-bitmap.h
@@ -20,6 +20,8 @@ BdrvDirtyBitmap *bdrv_dirty_bitmap_abdicate(BlockDriverState 
*bs,
 BdrvDirtyBitmap *bdrv_reclaim_dirty_bitmap(BlockDriverState *bs,
                                            BdrvDirtyBitmap *bitmap,
                                            Error **errp);
+void bdrv_dirty_bitmap_release_successor(BlockDriverState *bs,
+                                         BdrvDirtyBitmap *bitmap);
 void bdrv_dirty_bitmap_enable_successor(BdrvDirtyBitmap *bitmap);
 BdrvDirtyBitmap *bdrv_find_dirty_bitmap(BlockDriverState *bs,
                                         const char *name);
-- 
2.11.1