xen: fix is_disconnected_device/exists_disconnected_device

The logic of is_disconnected_device/exists_disconnected_device is wrong
in that they are used to test whether a device is trying to connect (i.e.
connecting).  For this reason the patch fixes them to not consider a
Closing or Closed device to be connecting.  At the same time the patch
also renames the functions according to what they really do; you could
say a closed device is "disconnected" (the old name), but not "connecting"
(the new name).

This patch is a backport of changeset 909 from the Xenbits tree.

Cc: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>

1 files changed, 7 insertions, 6 deletions

diff --git a/drivers/xen/xenbus/xenbus_probe.c b/drivers/xen/xenbus/xenbus_probe.c
index 3800da7dabfe..19bce3e1b333 100644
--- a/drivers/xen/xenbus/xenbus_probe.c
+++ b/drivers/xen/xenbus/xenbus_probe.c
@@ -843,7 +843,7 @@ postcore_initcall(xenbus_probe_init);
 
 MODULE_LICENSE("GPL");
 
-static int is_disconnected_device(struct device *dev, void *data)
+static int is_device_connecting(struct device *dev, void *data)
 {
         struct xenbus_device *xendev = to_xenbus_device(dev);
         struct device_driver *drv = data;
@@ -861,14 +861,15 @@ static int is_disconnected_device(struct device *dev, void *data)
                 return 0;
 
         xendrv = to_xenbus_driver(dev->driver);
-        return (xendev->state != XenbusStateConnected ||
-                (xendrv->is_ready && !xendrv->is_ready(xendev)));
+        return (xendev->state < XenbusStateConnected ||
+                (xendev->state == XenbusStateConnected &&
+                 xendrv->is_ready && !xendrv->is_ready(xendev)));
 }
 
-static int exists_disconnected_device(struct device_driver *drv)
+static int exists_connecting_device(struct device_driver *drv)
 {
         return bus_for_each_dev(&xenbus_frontend.bus, NULL, drv,
-                                is_disconnected_device);
+                                is_device_connecting);
 }
 
 static int print_device_status(struct device *dev, void *data)
@@ -918,7 +919,7 @@ static void wait_for_devices(struct xenbus_driver *xendrv)
         if (!ready_to_wait_for_devices || !xen_domain())
                 return;
 
-        while (exists_disconnected_device(drv)) {
+        while (exists_connecting_device(drv)) {
                 if (time_after(jiffies, timeout))
                         break;
                 schedule_timeout_interruptible(HZ/10);