2 files changed, 16 insertions, 0 deletions
diff --git a/include/block/block.h b/include/block/block.h
index 734c9d2f76..bff3317696 100644
--- a/include/block/block.h
+++ b/include/block/block.h
@@ -618,6 +618,13 @@ void bdrv_parent_drained_begin(BlockDriverState *bs, BdrvChild *ignore,
 void bdrv_parent_drained_begin_single(BdrvChild *c, bool poll);
 
 /**
+ * bdrv_parent_drained_end_single:
+ *
+ * End a quiesced section for the parent of @c.
+ */
+void bdrv_parent_drained_end_single(BdrvChild *c);
+
+/**
  * bdrv_parent_drained_end:
  *
  * End a quiesced section of all users of @bs. This is part of
diff --git a/include/block/block_int.h b/include/block/block_int.h
index 50902531b7..f5b044fcdb 100644
--- a/include/block/block_int.h
+++ b/include/block/block_int.h
@@ -729,6 +729,15 @@ struct BdrvChild {
      */
     bool frozen;
 
+    /*
+     * How many times the parent of this child has been drained
+     * (through role->drained_*).
+     * Usually, this is equal to bs->quiesce_counter (potentially
+     * reduced by bdrv_drain_all_count).  It may differ while the
+     * child is entering or leaving a drained section.
+     */
+    int parent_quiesce_counter;
+
     QLIST_ENTRY(BdrvChild) next;
     QLIST_ENTRY(BdrvChild) next_parent;
 };