+
+#define VHOST_LOG_PAGE 4096
+
+static __rte_always_inline void
+vhost_log_page(uint8_t *log_base, uint64_t page)
+{
+ log_base[page / 8] |= 1 << (page % 8);
+}
+
+static __rte_always_inline void
+vhost_log_write(struct virtio_net *dev, uint64_t addr, uint64_t len)
+{
+ uint64_t page;
+
+ if (likely(((dev->features & (1ULL << VHOST_F_LOG_ALL)) == 0) ||
+ !dev->log_base || !len))
+ return;
+
+ if (unlikely(dev->log_size <= ((addr + len - 1) / VHOST_LOG_PAGE / 8)))
+ return;
+
+ /* To make sure guest memory updates are committed before logging */
+ rte_smp_wmb();
+
+ page = addr / VHOST_LOG_PAGE;
+ while (page * VHOST_LOG_PAGE < addr + len) {
+ vhost_log_page((uint8_t *)(uintptr_t)dev->log_base, page);
+ page += 1;
+ }
+}
+
+static __rte_always_inline void
+vhost_log_used_vring(struct virtio_net *dev, struct vhost_virtqueue *vq,
+ uint64_t offset, uint64_t len)
+{
+ vhost_log_write(dev, vq->log_guest_addr + offset, len);
+}
+