+/* OST_LVB_ERR_INIT is needed because the return code in rc is
+ * negative, i.e. because ((MASK + rc) & MASK) != MASK. */
+#define OST_LVB_ERR_INIT 0xffbadbad80000000ULL
+#define OST_LVB_ERR_MASK 0xffbadbad00000000ULL
+#define OST_LVB_IS_ERR(blocks) \
+ ((blocks & OST_LVB_ERR_MASK) == OST_LVB_ERR_MASK)
+#define OST_LVB_SET_ERR(blocks, rc) \
+ do { blocks = OST_LVB_ERR_INIT + rc; } while (0)
+#define OST_LVB_GET_ERR(blocks) (int)(blocks - OST_LVB_ERR_INIT)
+