+uint64_t __vhost_iova_to_vva(struct virtio_net *dev, struct vhost_virtqueue *vq,
+ uint64_t iova, uint64_t size, uint8_t perm);
+int vring_translate(struct virtio_net *dev, struct vhost_virtqueue *vq);
+void vring_invalidate(struct virtio_net *dev, struct vhost_virtqueue *vq);
+
+static __rte_always_inline uint64_t
+vhost_iova_to_vva(struct virtio_net *dev, struct vhost_virtqueue *vq,
+ uint64_t iova, uint64_t size, uint8_t perm)
+{
+ if (!(dev->features & (1ULL << VIRTIO_F_IOMMU_PLATFORM)))
+ return rte_vhost_gpa_to_vva(dev->mem, iova);
+
+ return __vhost_iova_to_vva(dev, vq, iova, size, perm);
+}
+
+#define vhost_used_event(vr) \
+ (*(volatile uint16_t*)&(vr)->avail->ring[(vr)->size])
+
+/*
+ * The following is used with VIRTIO_RING_F_EVENT_IDX.
+ * Assuming a given event_idx value from the other size, if we have
+ * just incremented index from old to new_idx, should we trigger an
+ * event?
+ */
+static __rte_always_inline int
+vhost_need_event(uint16_t event_idx, uint16_t new_idx, uint16_t old)
+{
+ return (uint16_t)(new_idx - event_idx - 1) < (uint16_t)(new_idx - old);
+}
+
+static __rte_always_inline void
+vhost_vring_call(struct virtio_net *dev, struct vhost_virtqueue *vq)
+{
+ /* Flush used->idx update before we read avail->flags. */
+ rte_mb();
+
+ /* Don't kick guest if we don't reach index specified by guest. */
+ if (dev->features & (1ULL << VIRTIO_RING_F_EVENT_IDX)) {
+ uint16_t old = vq->signalled_used;
+ uint16_t new = vq->last_used_idx;
+
+ LOG_DEBUG(VHOST_DATA, "%s: used_event_idx=%d, old=%d, new=%d\n",
+ __func__,
+ vhost_used_event(vq),
+ old, new);
+ if (vhost_need_event(vhost_used_event(vq), new, old)
+ && (vq->callfd >= 0)) {
+ vq->signalled_used = vq->last_used_idx;
+ eventfd_write(vq->callfd, (eventfd_t) 1);
+ }
+ } else {
+ /* Kick the guest if necessary. */
+ if (!(vq->avail->flags & VRING_AVAIL_F_NO_INTERRUPT)
+ && (vq->callfd >= 0))
+ eventfd_write(vq->callfd, (eventfd_t)1);
+ }
+}
+