+ vhost_user_vring_t *vrings;
+
+ /*
+ * vrings is a dynamic array. It may have more elements than it is
+ * currently used. num_qid indicates the current total qid's in the
+ * vrings. For example, vec_len(vrings) = 64, num_qid = 60, so the
+ * current valid/used qid is (0, 59) in the vrings array.
+ */
+ u32 num_qid;