[RFC PATCH 08/12] vdpa: Add vhost_vdpa_start_control_svq

[Eugenio Pérez]

As a first step we only enable CVQ first than others. Future patches add
state restore.

Signed-off-by: Eugenio Pérez <eperezma@redhat.com>
---
 net/vhost-vdpa.c | 13 +++++++++++++
 1 file changed, 13 insertions(+)

diff --git a/net/vhost-vdpa.c b/net/vhost-vdpa.c
index 986e6414b4..211bd0468b 100644
--- a/net/vhost-vdpa.c
+++ b/net/vhost-vdpa.c
@@ -334,6 +334,18 @@ static bool vhost_vdpa_net_cvq_map_elem(VhostVDPAState *s,
     return true;
 }
 
+static int vhost_vdpa_start_control_svq(struct vhost_vdpa *v)
+{
+    struct vhost_vring_state state = {
+        .index = v->dev->vq_index,
+        .num = 1,
+    };
+    int r;
+
+    r = ioctl(v->device_fd, VHOST_VDPA_SET_VRING_ENABLE, &state);
+    return r < 0 ? -errno : r;
+}
+
 /**
  * Do not forward commands not supported by SVQ. Otherwise, the device could
  * accept it and qemu would not know how to update the device model.
@@ -493,6 +505,7 @@ static NetClientState *net_vhost_vdpa_init(NetClientState 
*peer,
                                             vhost_vdpa_net_cvq_cmd_page_len());
         memset(s->cvq_cmd_in_buffer, 0, vhost_vdpa_net_cvq_cmd_page_len());
 
+        s->vhost_vdpa.start_op = vhost_vdpa_start_control_svq;
         s->vhost_vdpa.shadow_vq_ops = &vhost_vdpa_net_svq_ops;
         s->vhost_vdpa.shadow_vq_ops_opaque = s;
         error_setg(&s->vhost_vdpa.migration_blocker,
-- 
2.31.1