+/* support mbuf with external buffer attached */
+#define RTE_VHOST_USER_EXTBUF_SUPPORT (1ULL << 5)
+/* support only linear buffers (no chained mbufs) */
+#define RTE_VHOST_USER_LINEARBUF_SUPPORT (1ULL << 6)
+#define RTE_VHOST_USER_ASYNC_COPY (1ULL << 7)
+
+/* Features. */
+#ifndef VIRTIO_NET_F_GUEST_ANNOUNCE
+ #define VIRTIO_NET_F_GUEST_ANNOUNCE 21
+#endif
+
+#ifndef VIRTIO_NET_F_MQ
+ #define VIRTIO_NET_F_MQ 22
+#endif
+
+#ifndef VIRTIO_NET_F_MTU
+ #define VIRTIO_NET_F_MTU 3
+#endif
+
+#ifndef VIRTIO_F_ANY_LAYOUT
+ #define VIRTIO_F_ANY_LAYOUT 27
+#endif