-uint64_t ll_lookup (list_t *ll, uint64_t key);
-uint64_t ll_add (list_t *ll, uint64_t key, uint64_t value);
-uint64_t ll_remove (list_t *ll, uint64_t key);
+uint64_t ll_lookup (list_t *ll, const void *key_data, uint32_t key_len);
+uint64_t ll_cas (list_t *ll, const void *key_data, uint32_t key_len, uint64_t expected_val, uint64_t new_val);
+uint64_t ll_remove (list_t *ll, const void *key_data, uint32_t key_len);