--- c2287313b98598917bc6f7e194c25a2a6b0b6cb3
+++ 680dcbb2d91ee75ddaaa1d0236962974a96d4696
@@ -513,6 +513,15 @@ static atomic_t vmap_lazy_nr = ATOMIC_IN
 static void purge_fragmented_blocks_allcpus(void);
 
 /*
+ * called before a call to iounmap() if the caller wants vm_area_struct's
+ * immediately freed.
+ */
+void set_iounmap_nonlazy(void)
+{
+	atomic_set(&vmap_lazy_nr, lazy_max_pages()+1);
+}
+
+/*
  * Purges all lazily-freed vmap areas.
  *
  * If sync is 0 then don't purge if there is already a purge in progress.