diff --git a/lib/constants.py b/lib/constants.py
index f20117d13c22ab9c04e65cc27a577747a9c325aa..9ffa3d1f22ee9ebc19639e02eec99c8f971a0c2a 100644
--- a/lib/constants.py
+++ b/lib/constants.py
@@ -175,6 +175,7 @@ DTS_NOT_LVM = frozenset([DT_DISKLESS, DT_FILE])
 LD_LV = "lvm"
 LD_DRBD8 = "drbd8"
 LD_FILE = "file"
+LDS_BLOCK = frozenset([LD_LV, LD_DRBD8])
 
 # drbd constants
 DRBD_HMAC_ALG = "md5"