[RFC PATCH v9 04/23] vhost: Get vring base from vq, not svq

["Eugenio Pérez" <eperezma@redhat.com>]

The used idx used to match with this, but it will not match from the
moment we introduce svq_inject. Rewind all the descriptors not used by
vdpa device and get the vq state properly.

Signed-off-by: Eugenio Pérez <eperezma@redhat.com>
---
 include/hw/virtio/virtio.h | 1 +
 hw/virtio/vhost-vdpa.c     | 7 +++----
 hw/virtio/virtio.c         | 5 +++++
 3 files changed, 9 insertions(+), 4 deletions(-)

diff --git a/include/hw/virtio/virtio.h b/include/hw/virtio/virtio.h
index db1c0ddf6b..4b51ab9d06 100644
--- a/include/hw/virtio/virtio.h
+++ b/include/hw/virtio/virtio.h
@@ -302,6 +302,7 @@ hwaddr virtio_queue_get_desc_size(VirtIODevice *vdev, int n);
 hwaddr virtio_queue_get_avail_size(VirtIODevice *vdev, int n);
 hwaddr virtio_queue_get_used_size(VirtIODevice *vdev, int n);
 unsigned int virtio_queue_get_last_avail_idx(VirtIODevice *vdev, int n);
+unsigned int virtio_queue_get_in_use(const VirtQueue *vq);
 void virtio_queue_set_last_avail_idx(VirtIODevice *vdev, int n,
                                      unsigned int idx);
 void virtio_queue_restore_last_avail_idx(VirtIODevice *vdev, int n);
diff --git a/hw/virtio/vhost-vdpa.c b/hw/virtio/vhost-vdpa.c
index 2ee8009594..de76128030 100644
--- a/hw/virtio/vhost-vdpa.c
+++ b/hw/virtio/vhost-vdpa.c
@@ -1189,12 +1189,10 @@ static int vhost_vdpa_get_vring_base(struct vhost_dev *dev,
                                        struct vhost_vring_state *ring)
 {
     struct vhost_vdpa *v = dev->opaque;
-    int vdpa_idx = ring->index - dev->vq_index;
     int ret;
 
     if (v->shadow_vqs_enabled) {
-        VhostShadowVirtqueue *svq = g_ptr_array_index(v->shadow_vqs, vdpa_idx);
-
+        const VirtQueue *vq = virtio_get_queue(dev->vdev, ring->index);
         /*
          * Setting base as last used idx, so destination will see as available
          * all the entries that the device did not use, including the in-flight
@@ -1203,7 +1201,8 @@ static int vhost_vdpa_get_vring_base(struct vhost_dev *dev,
          * TODO: This is ok for networking, but other kinds of devices might
          * have problems with these retransmissions.
          */
-        ring->num = svq->last_used_idx;
+        ring->num = virtio_queue_get_last_avail_idx(dev->vdev, ring->index) -
+                    virtio_queue_get_in_use(vq);
         return 0;
     }
 
diff --git a/hw/virtio/virtio.c b/hw/virtio/virtio.c
index 5d607aeaa0..e02656f7a2 100644
--- a/hw/virtio/virtio.c
+++ b/hw/virtio/virtio.c
@@ -3420,6 +3420,11 @@ unsigned int virtio_queue_get_last_avail_idx(VirtIODevice *vdev, int n)
     }
 }
 
+unsigned int virtio_queue_get_in_use(const VirtQueue *vq)
+{
+    return vq->inuse;
+}
+
 static void virtio_queue_packed_set_last_avail_idx(VirtIODevice *vdev,
                                                    int n, unsigned int idx)
 {
-- 
2.31.1