From d42fea8a40c4a5d8909103910d86da8e674d1fb2 Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?Eugenio=20P=C3=A9rez?= Date: Mon, 14 Mar 2022 18:34:52 +0100 Subject: [PATCH] vdpa: Adapt vhost_vdpa_get_vring_base to SVQ MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit This is needed to achieve migration, so the destination can restore its 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 processing ones. This is ok for networking, but other kinds of devices might have problems with these retransmissions. Signed-off-by: Eugenio Pérez Acked-by: Michael S. Tsirkin Signed-off-by: Jason Wang Signed-off-by: fangyi --- hw/virtio/vhost-vdpa.c | 17 +++++++++++++++++ 1 file changed, 17 insertions(+) diff --git a/hw/virtio/vhost-vdpa.c b/hw/virtio/vhost-vdpa.c index 8245345bcd..428137f654 100644 --- a/hw/virtio/vhost-vdpa.c +++ b/hw/virtio/vhost-vdpa.c @@ -1143,8 +1143,25 @@ static int vhost_vdpa_set_vring_base(struct vhost_dev *dev, static int vhost_vdpa_get_vring_base(struct vhost_dev *dev, struct vhost_vring_state *ring) { + struct vhost_vdpa *v = dev->opaque; int ret; + if (v->shadow_vqs_enabled) { + VhostShadowVirtqueue *svq = g_ptr_array_index(v->shadow_vqs, + 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 + * processing ones. + * + * TODO: This is ok for networking, but other kinds of devices might + * have problems with these retransmissions. + */ + ring->num = svq->last_used_idx; + return 0; + } + ret = vhost_vdpa_call(dev, VHOST_GET_VRING_BASE, ring); trace_vhost_vdpa_get_vring_base(dev, ring->index, ring->num); return ret; -- 2.27.0