1 files changed, 49 insertions, 0 deletions
diff --git a/block.c b/block.c
index 724b3b2db5..0726dab8d0 100644
--- a/block.c
+++ b/block.c
@@ -4011,3 +4011,52 @@ void bdrv_refresh_filename(BlockDriverState *bs)
         QDECREF(json);
     }
 }
+
+/*
+ * Hot add/remove a BDS's child. So the user can take a child offline when
+ * it is broken and take a new child online
+ */
+void bdrv_add_child(BlockDriverState *parent_bs, BlockDriverState *child_bs,
+                    Error **errp)
+{
+
+    if (!parent_bs->drv || !parent_bs->drv->bdrv_add_child) {
+        error_setg(errp, "The node %s does not support adding a child",
+                   bdrv_get_device_or_node_name(parent_bs));
+        return;
+    }
+
+    if (!QLIST_EMPTY(&child_bs->parents)) {
+        error_setg(errp, "The node %s already has a parent",
+                   child_bs->node_name);
+        return;
+    }
+
+    parent_bs->drv->bdrv_add_child(parent_bs, child_bs, errp);
+}
+
+void bdrv_del_child(BlockDriverState *parent_bs, BdrvChild *child, Error **errp)
+{
+    BdrvChild *tmp;
+
+    if (!parent_bs->drv || !parent_bs->drv->bdrv_del_child) {
+        error_setg(errp, "The node %s does not support removing a child",
+                   bdrv_get_device_or_node_name(parent_bs));
+        return;
+    }
+
+    QLIST_FOREACH(tmp, &parent_bs->children, next) {
+        if (tmp == child) {
+            break;
+        }
+    }
+
+    if (!tmp) {
+        error_setg(errp, "The node %s does not have a child named %s",
+                   bdrv_get_device_or_node_name(parent_bs),
+                   bdrv_get_device_or_node_name(child->bs));
+        return;
+    }
+
+    parent_bs->drv->bdrv_del_child(parent_bs, child, errp);
+}