diff --git a/stmhal/moduos.c b/stmhal/moduos.c
index d206ee1d83..cb2a73c116 100644
--- a/stmhal/moduos.c
+++ b/stmhal/moduos.c
@@ -454,6 +454,9 @@ STATIC const mp_map_elem_t os_module_globals_table[] = {
 
     // these are MicroPython extensions
     { MP_OBJ_NEW_QSTR(MP_QSTR_dupterm), (mp_obj_t)&mod_os_dupterm_obj },
+    { MP_OBJ_NEW_QSTR(MP_QSTR_mount), (mp_obj_t)&fsuser_mount_obj },
+    { MP_OBJ_NEW_QSTR(MP_QSTR_umount), (mp_obj_t)&fsuser_umount_obj },
+    { MP_OBJ_NEW_QSTR(MP_QSTR_mkfs), (mp_obj_t)&fsuser_mkfs_obj },
 };
 
 STATIC MP_DEFINE_CONST_DICT(os_module_globals, os_module_globals_table);