[XENBUS] Make frontend drivers shutdown cleanly.

This patch makes frontend drivers being shutdown when devices_shutdown()
is called and walks down the device tree.  Most of it is handled by the
xenbus core, which got a new function for the bus->shutdown callback.

Signed-off-by: Gerd Hoffmann <kraxel@suse.de>

diff --git a/linux-2.6-xen-sparse/drivers/xen/blkfront/blkfront.c b/linux-2.6-xen-sparse/drivers/xen/blkfront/blkfront.c
index 9f180fd01fe9beb2cc0578ce34828e4f7c8e41df..4c44d7608d4b2e165748dc916585b890a45fafbd 100644 (file)
--- a/linux-2.6-xen-sparse/drivers/xen/blkfront/blkfront.c
+++ b/linux-2.6-xen-sparse/drivers/xen/blkfront/blkfront.c
@@ -273,7 +273,7 @@ static void backend_changed(struct xenbus_device *dev,
                        xenbus_dev_fatal(dev, -ENODEV, "bdget failed");
 
                down(&bd->bd_sem);
-               if (info->users > 0)
+               if (info->users > 0 && system_state == SYSTEM_RUNNING)
                        xenbus_dev_error(dev, -EBUSY,
                                         "Device in use; refusing to close");
                else
@@ -360,7 +360,7 @@ static void blkfront_closing(struct xenbus_device *dev)
 
        xlvbd_del(info);
 
-       xenbus_switch_state(dev, XenbusStateClosed);
+       xenbus_frontend_closed(dev);
 }
 
 

diff --git a/linux-2.6-xen-sparse/drivers/xen/netfront/netfront.c b/linux-2.6-xen-sparse/drivers/xen/netfront/netfront.c
index 136d1ea4207e839692cc4985d0a7c39434dbeffc..a257cb60643817367450ca9d9e429c314236acf5 100644 (file)
--- a/linux-2.6-xen-sparse/drivers/xen/netfront/netfront.c
+++ b/linux-2.6-xen-sparse/drivers/xen/netfront/netfront.c
@@ -486,7 +486,7 @@ static void backend_changed(struct xenbus_device *dev,
        struct netfront_info *np = dev->dev.driver_data;
        struct net_device *netdev = np->netdev;
 
-       DPRINTK("\n");
+       DPRINTK("%s\n", xenbus_strstate(backend_state));
 
        switch (backend_state) {
        case XenbusStateInitialising:
@@ -1936,11 +1936,10 @@ static void netfront_closing(struct xenbus_device *dev)
 {
        struct netfront_info *info = dev->dev.driver_data;
 
-       DPRINTK("netfront_closing: %s removed\n", dev->nodename);
+       DPRINTK("%s\n", dev->nodename);
 
        close_netdev(info);
-
-       xenbus_switch_state(dev, XenbusStateClosed);
+       xenbus_frontend_closed(dev);
 }
 
 

diff --git a/linux-2.6-xen-sparse/drivers/xen/xenbus/xenbus_client.c b/linux-2.6-xen-sparse/drivers/xen/xenbus/xenbus_client.c
index e08e88818eac3a042fb35ebfd0fbf286a5750280..9b389ec06bfd651aa3db7c2f60e17da2d9becb4f 100644 (file)
--- a/linux-2.6-xen-sparse/drivers/xen/xenbus/xenbus_client.c
+++ b/linux-2.6-xen-sparse/drivers/xen/xenbus/xenbus_client.c
@@ -138,6 +138,13 @@ int xenbus_switch_state(struct xenbus_device *dev, enum xenbus_state state)
 }
 EXPORT_SYMBOL_GPL(xenbus_switch_state);
 
+int xenbus_frontend_closed(struct xenbus_device *dev)
+{
+       xenbus_switch_state(dev, XenbusStateClosed);
+       complete(&dev->down);
+       return 0;
+}
+EXPORT_SYMBOL_GPL(xenbus_frontend_closed);
 
 /**
  * Return the path to the error node for the given device, or NULL on failure.

diff --git a/linux-2.6-xen-sparse/drivers/xen/xenbus/xenbus_probe.c b/linux-2.6-xen-sparse/drivers/xen/xenbus/xenbus_probe.c
index 4f5be0fe2e00cfad6886c5ab913002a6ebb80611..bcd1f6df06845f51f0b0b77e2ffdd83f9cadd796 100644 (file)
--- a/linux-2.6-xen-sparse/drivers/xen/xenbus/xenbus_probe.c
+++ b/linux-2.6-xen-sparse/drivers/xen/xenbus/xenbus_probe.c
@@ -73,6 +73,7 @@ static int xenbus_probe_backend(const char *type, const char *domid);
 
 static int xenbus_dev_probe(struct device *_dev);
 static int xenbus_dev_remove(struct device *_dev);
+static void xenbus_dev_shutdown(struct device *_dev);
 
 /* If something in array of ids matches this device, return it. */
 static const struct xenbus_device_id *
@@ -192,6 +193,7 @@ static struct xen_bus_type xenbus_frontend = {
                .match    = xenbus_match,
                .probe    = xenbus_dev_probe,
                .remove   = xenbus_dev_remove,
+               .shutdown = xenbus_dev_shutdown,
        },
        .dev = {
                .bus_id = "xen",
@@ -246,6 +248,7 @@ static struct xen_bus_type xenbus_backend = {
                .match    = xenbus_match,
                .probe    = xenbus_dev_probe,
                .remove   = xenbus_dev_remove,
+//             .shutdown = xenbus_dev_shutdown,
                .uevent   = xenbus_uevent_backend,
        },
        .dev = {
@@ -349,7 +352,7 @@ static int xenbus_dev_probe(struct device *_dev)
        const struct xenbus_device_id *id;
        int err;
 
-       DPRINTK("");
+       DPRINTK("%s", dev->nodename);
 
        if (!drv->probe) {
                err = -ENODEV;
@@ -394,7 +397,7 @@ static int xenbus_dev_remove(struct device *_dev)
        struct xenbus_device *dev = to_xenbus_device(_dev);
        struct xenbus_driver *drv = to_xenbus_driver(_dev->driver);
 
-       DPRINTK("");
+       DPRINTK("%s", dev->nodename);
 
        free_otherend_watch(dev);
        free_otherend_details(dev);
@@ -406,6 +409,27 @@ static int xenbus_dev_remove(struct device *_dev)
        return 0;
 }
 
+static void xenbus_dev_shutdown(struct device *_dev)
+{
+       struct xenbus_device *dev = to_xenbus_device(_dev);
+       unsigned long timeout = 5*HZ;
+
+       DPRINTK("%s", dev->nodename);
+
+       get_device(&dev->dev);
+       if (dev->state != XenbusStateConnected) {
+               printk("%s: %s: %s != Connected, skipping\n", __FUNCTION__,
+                      dev->nodename, xenbus_strstate(dev->state));
+               goto out;
+       }
+       xenbus_switch_state(dev, XenbusStateClosing);
+       timeout = wait_for_completion_timeout(&dev->down, timeout);
+       if (!timeout)
+               printk("%s: %s timeout closing device\n", __FUNCTION__, dev->nodename);
+ out:
+       put_device(&dev->dev);
+}
+
 static int xenbus_register_driver_common(struct xenbus_driver *drv,
                                         struct xen_bus_type *bus)
 {
@@ -588,6 +612,7 @@ static int xenbus_probe_node(struct xen_bus_type *bus,
        tmpstring += strlen(tmpstring) + 1;
        strcpy(tmpstring, type);
        xendev->devicetype = tmpstring;
+       init_completion(&xendev->down);
 
        xendev->dev.parent = &bus->dev;
        xendev->dev.bus = &bus->bus;

diff --git a/linux-2.6-xen-sparse/include/xen/xenbus.h b/linux-2.6-xen-sparse/include/xen/xenbus.h
index cd09eb89855940c8cdbab4d9b5aa689118533c7f..8e259ce777fc40ab7c98927a6cd9892bbf891a2d 100644 (file)
--- a/linux-2.6-xen-sparse/include/xen/xenbus.h
+++ b/linux-2.6-xen-sparse/include/xen/xenbus.h
@@ -37,6 +37,7 @@
 #include <linux/device.h>
 #include <linux/notifier.h>
 #include <linux/mutex.h>
+#include <linux/completion.h>
 #include <xen/interface/xen.h>
 #include <xen/interface/grant_table.h>
 #include <xen/interface/io/xenbus.h>
@@ -74,6 +75,7 @@ struct xenbus_device {
        struct xenbus_watch otherend_watch;
        struct device dev;
        enum xenbus_state state;
+       struct completion down;
 };
 
 static inline struct xenbus_device *to_xenbus_device(struct device *dev)
@@ -299,5 +301,6 @@ int __init xenbus_dev_init(void);
 
 char *xenbus_strstate(enum xenbus_state state);
 int xenbus_dev_is_online(struct xenbus_device *dev);
+int xenbus_frontend_closed(struct xenbus_device *dev);
 
 #endif /* _XEN_XENBUS_H */