xen-netback: Don't destroy the netdev until the vif is shut down
Without this patch, if a frontend cycles through states Closing
and Closed (which Windows frontends need to do) then the netdev
will be destroyed and requires re-invocation of hotplug scripts
to restore state before the frontend can move to Connected. Thus
when udev is not in use the backend gets stuck in InitWait.
With this patch, the netdev is left alone whilst the backend is
still online and is only de-registered and freed just prior to
destroying the vif (which is also nicely symmetrical with the
netdev allocation and registration being done during probe) so
no re-invocation of hotplug scripts is required.
Signed-off-by: Paul Durrant <paul.durrant@citrix.com>
Cc: David Vrabel <david.vrabel@citrix.com>
Cc: Wei Liu <wei.liu2@citrix.com>
Cc: Ian Campbell <ian.campbell@citrix.com>
Acked-by: Wei Liu <wei.liu2@citrix.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/drivers/net/xen-netback/interface.c b/drivers/net/xen-netback/interface.c
index 77fee1d..01bb854 100644
--- a/drivers/net/xen-netback/interface.c
+++ b/drivers/net/xen-netback/interface.c
@@ -353,6 +353,9 @@
}
netdev_dbg(dev, "Successfully created xenvif\n");
+
+ __module_get(THIS_MODULE);
+
return vif;
}
@@ -366,8 +369,6 @@
if (vif->tx_irq)
return 0;
- __module_get(THIS_MODULE);
-
err = xenvif_map_frontend_rings(vif, tx_ring_ref, rx_ring_ref);
if (err < 0)
goto err;
@@ -452,12 +453,6 @@
void xenvif_disconnect(struct xenvif *vif)
{
- /* Disconnect funtion might get called by generic framework
- * even before vif connects, so we need to check if we really
- * need to do a module_put.
- */
- int need_module_put = 0;
-
if (netif_carrier_ok(vif->dev))
xenvif_carrier_off(vif);
@@ -468,23 +463,22 @@
unbind_from_irqhandler(vif->tx_irq, vif);
unbind_from_irqhandler(vif->rx_irq, vif);
}
- /* vif->irq is valid, we had a module_get in
- * xenvif_connect.
- */
- need_module_put = 1;
+ vif->tx_irq = 0;
}
if (vif->task)
kthread_stop(vif->task);
+ xenvif_unmap_frontend_rings(vif);
+}
+
+void xenvif_free(struct xenvif *vif)
+{
netif_napi_del(&vif->napi);
unregister_netdev(vif->dev);
- xenvif_unmap_frontend_rings(vif);
-
free_netdev(vif->dev);
- if (need_module_put)
- module_put(THIS_MODULE);
+ module_put(THIS_MODULE);
}