vhost: implement vhost_vq_get_addr method

use vhost_vq_get_addr callback to get the vq address from backend

Signed-off-by: Cindy Lu <[email protected]>
Message-Id: <[email protected]>
Reviewed-by: Michael S. Tsirkin <[email protected]>
Signed-off-by: Michael S. Tsirkin <[email protected]>
Acked-by: Jason Wang <[email protected]>

Author: lulu-github-name

hw/virtio/vhost.c

@@ -773,15 +773,25 @@ static int vhost_virtqueue_set_addr(struct vhost_dev *dev,
                                     struct vhost_virtqueue *vq,
                                     unsigned idx, bool enable_log)
 {
-    struct vhost_vring_addr addr = {
-        .index = idx,
-        .desc_user_addr = (uint64_t)(unsigned long)vq->desc,
-        .avail_user_addr = (uint64_t)(unsigned long)vq->avail,
-        .used_user_addr = (uint64_t)(unsigned long)vq->used,
-        .log_guest_addr = vq->used_phys,
-        .flags = enable_log ? (1 << VHOST_VRING_F_LOG) : 0,
-    };
-    int r = dev->vhost_ops->vhost_set_vring_addr(dev, &addr);
+    struct vhost_vring_addr addr;
+    int r;
+    memset(&addr, 0, sizeof(struct vhost_vring_addr));
+
+    if (dev->vhost_ops->vhost_vq_get_addr) {
+        r = dev->vhost_ops->vhost_vq_get_addr(dev, &addr, vq);
+        if (r < 0) {
+            VHOST_OPS_DEBUG("vhost_vq_get_addr failed");
+            return -errno;
+        }
+    } else {
+        addr.desc_user_addr = (uint64_t)(unsigned long)vq->desc;
+        addr.avail_user_addr = (uint64_t)(unsigned long)vq->avail;
+        addr.used_user_addr = (uint64_t)(unsigned long)vq->used;
+    }
+    addr.index = idx;
+    addr.log_guest_addr = vq->used_phys;
+    addr.flags = enable_log ? (1 << VHOST_VRING_F_LOG) : 0;
+    r = dev->vhost_ops->vhost_set_vring_addr(dev, &addr);
     if (r < 0) {
         VHOST_OPS_DEBUG("vhost_set_vring_addr failed");
         return -errno;

include/hw/virtio/vhost-backend.h

@@ -118,6 +118,9 @@ typedef int (*vhost_dev_start_op)(struct vhost_dev *dev, bool started);
 typedef int (*vhost_vq_get_addr_op)(struct vhost_dev *dev,
                     struct vhost_vring_addr *addr,
                     struct vhost_virtqueue *vq);
+
+typedef int (*vhost_get_device_id_op)(struct vhost_dev *dev, uint32_t *dev_id);
+
 typedef struct VhostOps {
     VhostBackendType backend_type;
     vhost_backend_init vhost_backend_init;
@@ -160,6 +163,7 @@ typedef struct VhostOps {
     vhost_set_inflight_fd_op vhost_set_inflight_fd;
     vhost_dev_start_op vhost_dev_start;
     vhost_vq_get_addr_op  vhost_vq_get_addr;
+    vhost_get_device_id_op vhost_get_device_id;
 } VhostOps;
 
 extern const VhostOps user_ops;