[Qemu-devel] [PATCH RFC 08/14] vhost: add vhost_dev stop callback

[marcandre . lureau]

From: Marc-André Lureau <address@hidden>

vhost backend may want to stop the device, for example if it wants to
restart itself (translates to a link down for vhost-net).

Signed-off-by: Marc-André Lureau <address@hidden>
---
 hw/net/vhost_net.c        | 13 +++++++++++++
 include/hw/virtio/vhost.h |  4 ++++
 2 files changed, 17 insertions(+)

diff --git a/hw/net/vhost_net.c b/hw/net/vhost_net.c
index ea15220..f977e2d 100644
--- a/hw/net/vhost_net.c
+++ b/hw/net/vhost_net.c
@@ -134,6 +134,18 @@ static int vhost_net_get_fd(NetClientState *backend)
     }
 }
 
+static void vhost_net_backend_stop(struct vhost_dev *dev)
+{
+    struct vhost_net *net = container_of(dev, struct vhost_net, dev);
+    NetClientState *nc = net->nc;
+    NetClientState *peer = nc->peer;
+
+    peer->link_down = 1;
+    if (peer->info->link_status_changed) {
+        peer->info->link_status_changed(peer);
+    }
+}
+
 struct vhost_net *vhost_net_init(VhostNetOptions *options)
 {
     int r;
@@ -163,6 +175,7 @@ struct vhost_net *vhost_net_init(VhostNetOptions *options)
 
     net->dev.nvqs = 2;
     net->dev.vqs = net->vqs;
+    net->dev.stop = vhost_net_backend_stop;
 
     r = vhost_dev_init(&net->dev, options->opaque,
                        options->backend_type);
diff --git a/include/hw/virtio/vhost.h b/include/hw/virtio/vhost.h
index ab1dcac..48efd87 100644
--- a/include/hw/virtio/vhost.h
+++ b/include/hw/virtio/vhost.h
@@ -35,6 +35,8 @@ struct vhost_log {
     vhost_log_chunk_t *log;
 };
 
+typedef void (*vhost_stop)(struct vhost_dev *dev);
+
 struct vhost_memory;
 struct vhost_dev {
     MemoryListener memory_listener;
@@ -59,6 +61,8 @@ struct vhost_dev {
     const VhostOps *vhost_ops;
     void *opaque;
     struct vhost_log *log;
+    /* backend request to stop */
+    vhost_stop stop;
 };
 
 int vhost_dev_init(struct vhost_dev *hdev, void *opaque,
-- 
2.4.3