Fix bus watch code, and clean up a little.

Signed-off-by: Rusty Russel <rusty@rustcorp.com.au>
Signed-off-by: Christian Limpach <Christian.Limpach@cl.cam.ac.uk>

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 abf9f834bf728fde7e8a2e068db72e9b05c081d4..2b3fe0d967da6f6739e5752307518138663700c6 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
@@ -233,29 +233,25 @@ static unsigned int char_count(const char *str, char c)
 static void dev_changed(struct xenbus_watch *watch, const char *node)
 {
        char busid[BUS_ID_SIZE];
-       unsigned int typelen, idlen;
        int exists;
        struct xenbus_device *dev;
-       char *type;
+       char *p;
 
        /* Node is of form device/<type>/<identifier>[/...] */
-       if (char_count(node, '/') != 3)
+       if (char_count(node, '/') != 2)
                return;
 
-       type = strchr(node, '/');
-       type++;
-       typelen = strcspn(type, "/");
-       idlen = strcspn(type + typelen + 1, "/");
-       if (typelen + strlen("-") + idlen + 1 > BUS_ID_SIZE) {
+       /* Created or deleted? */
+       exists = xenbus_exists(node, "");
+
+       p = strchr(node, '/') + 1;
+       if (strlen(p) + 1 > BUS_ID_SIZE) {
                printk("Device for node %s is too big!\n", node);
                return;
        }
-
-       /* Does it exist? */
-       exists = xenbus_exists(node, "");
-
-       /* Create it with a / so we can see if it exists. */
-       sprintf(busid, "%.*s-%.*s", typelen, type, idlen, type + typelen + 1);
+       /* Bus ID is name with / changed to - */
+       strcpy(busid, p);
+       *strchr(busid, '/') = '-';
 
        dev = xenbus_device_find(busid);
        printk("xenbus: device %s %s\n", busid, dev ? "exists" : "new");
@@ -263,12 +259,14 @@ static void dev_changed(struct xenbus_watch *watch, const char *node)
                printk("xenbus: Unregistering device %s\n", busid);
                /* FIXME: free? */
                device_unregister(&dev->dev);
-       }
-       if (!dev && exists) {
+       } else if (!dev && exists) {
                printk("xenbus: Adding device %s\n", busid);
-               busid[typelen] = '\0';
-               xenbus_probe_device("device", busid, busid+typelen+1);
-       }
+               /* Hack bus id back into two strings. */
+               *strrchr(busid, '-') = '\0';
+               xenbus_probe_device("device", busid, busid+strlen(busid)+1);
+       } else
+               printk("xenbus: strange, %s already %s\n", busid,
+                      exists ? "exists" : "gone");
        if (dev)
                put_device(&dev->dev);
 }