3 files changed, 67 insertions, 23 deletions

diff --git a/lib/kobject.c b/lib/kobject.c
index 057921c5945a..cecf2fbede3e 100644
--- a/lib/kobject.c
+++ b/lib/kobject.c
@@ -157,7 +157,7 @@ static void unlink(struct kobject * kobj)
 }
 
 /**
- *      kobject_add - add an object to the hierarchy.
+ *      kobject_shadow_add - add an object to the hierarchy.
  *      @kobj:  object.
  *      @shadow_parent: sysfs directory to add to.
  */
@@ -174,6 +174,7 @@ int kobject_shadow_add(struct kobject * kobj, struct dentry *shadow_parent)
         if (!*kobj->k_name) {
                 pr_debug("kobject attempted to be registered with no name!\n");
                 WARN_ON(1);
+                kobject_put(kobj);
                 return -EINVAL;
         }
         parent = kobject_get(kobj->parent);
@@ -190,8 +191,8 @@ int kobject_shadow_add(struct kobject * kobj, struct dentry *shadow_parent)
 
                 list_add_tail(&kobj->entry,&kobj->kset->list);
                 spin_unlock(&kobj->kset->list_lock);
+                kobj->parent = parent;
         }
-        kobj->parent = parent;
 
         error = create_dir(kobj, shadow_parent);
         if (error) {
@@ -311,13 +312,43 @@ EXPORT_SYMBOL(kobject_set_name);
 int kobject_rename(struct kobject * kobj, const char *new_name)
 {
         int error = 0;
+        const char *devpath = NULL;
+        char *devpath_string = NULL;
+        char *envp[2];
 
         kobj = kobject_get(kobj);
         if (!kobj)
                 return -EINVAL;
         if (!kobj->parent)
                 return -EINVAL;
+
+        devpath = kobject_get_path(kobj, GFP_KERNEL);
+        if (!devpath) {
+                error = -ENOMEM;
+                goto out;
+        }
+        devpath_string = kmalloc(strlen(devpath) + 15, GFP_KERNEL);
+        if (!devpath_string) {
+                error = -ENOMEM;
+                goto out;
+        }
+        sprintf(devpath_string, "DEVPATH_OLD=%s", devpath);
+        envp[0] = devpath_string;
+        envp[1] = NULL;
+        /* Note : if we want to send the new name alone, not the full path,
+         * we could probably use kobject_name(kobj); */
+
         error = sysfs_rename_dir(kobj, kobj->parent->dentry, new_name);
+
+        /* This function is mostly/only used for network interface.
+         * Some hotplug package track interfaces by their name and
+         * therefore want to know when the name is changed by the user. */
+        if (!error)
+                kobject_uevent_env(kobj, KOBJ_MOVE, envp);
+
+out:
+        kfree(devpath_string);
+        kfree(devpath);
         kobject_put(kobj);
 
         return error;
@@ -488,13 +519,15 @@ static struct kobj_type dir_ktype = {
 };
 
 /**
- *      kobject_add_dir - add sub directory of object.
+ *      kobject_kset_add_dir - add sub directory of object.
+ *      @kset:          kset the directory is belongs to.
  *      @parent:        object in which a directory is created.
  *      @name:  directory name.
  *
  *      Add a plain directory object as child of given object.
  */
-struct kobject *kobject_add_dir(struct kobject *parent, const char *name)
+struct kobject *kobject_kset_add_dir(struct kset *kset,
+                                     struct kobject *parent, const char *name)
 {
         struct kobject *k;
         int ret;
@@ -506,13 +539,14 @@ struct kobject *kobject_add_dir(struct kobject *parent, const char *name)
         if (!k)
                 return NULL;
 
+        k->kset = kset;
         k->parent = parent;
         k->ktype = &dir_ktype;
         kobject_set_name(k, name);
         ret = kobject_register(k);
         if (ret < 0) {
-                printk(KERN_WARNING "kobject_add_dir: "
-                        "kobject_register error: %d\n", ret);
+                printk(KERN_WARNING "%s: kobject_register error: %d\n",
+                        __func__, ret);
                 kobject_del(k);
                 return NULL;
         }
@@ -521,6 +555,18 @@ struct kobject *kobject_add_dir(struct kobject *parent, const char *name)
 }
 
 /**
+ *      kobject_add_dir - add sub directory of object.
+ *      @parent:        object in which a directory is created.
+ *      @name:  directory name.
+ *
+ *      Add a plain directory object as child of given object.
+ */
+struct kobject *kobject_add_dir(struct kobject *parent, const char *name)
+{
+        return kobject_kset_add_dir(NULL, parent, name);
+}
+
+/**
  *      kset_init - initialize a kset for use
  *      @k:     kset 
  */
@@ -613,7 +659,6 @@ struct kobject * kset_find_obj(struct kset * kset, const char * name)
 
 void subsystem_init(struct subsystem * s)
 {
-        init_rwsem(&s->rwsem);
         kset_init(&s->kset);
 }
 
@@ -622,8 +667,7 @@ void subsystem_init(struct subsystem * s)
  *      @s:     the subsystem we're registering.
  *
  *      Once we register the subsystem, we want to make sure that 
- *      the kset points back to this subsystem for correct usage of 
- *      the rwsem. 
+ *      the kset points back to this subsystem.
  */
 
 int subsystem_register(struct subsystem * s)
diff --git a/lib/kobject_uevent.c b/lib/kobject_uevent.c
index 82fc1794b691..12e311dc664c 100644
--- a/lib/kobject_uevent.c
+++ b/lib/kobject_uevent.c
@@ -42,10 +42,6 @@ static char *action_to_string(enum kobject_action action)
                 return "remove";
         case KOBJ_CHANGE:
                 return "change";
-        case KOBJ_MOUNT:
-                return "mount";
-        case KOBJ_UMOUNT:
-                return "umount";
         case KOBJ_OFFLINE:
                 return "offline";
         case KOBJ_ONLINE:
@@ -95,10 +91,8 @@ int kobject_uevent_env(struct kobject *kobj, enum kobject_action action,
 
         /* search the kset we belong to */
         top_kobj = kobj;
-        if (!top_kobj->kset && top_kobj->parent) {
-                do {
-                        top_kobj = top_kobj->parent;
-                } while (!top_kobj->kset && top_kobj->parent);
+        while (!top_kobj->kset && top_kobj->parent) {
+                top_kobj = top_kobj->parent;
         }
         if (!top_kobj->kset) {
                 pr_debug("kobject attempted to send uevent without kset!\n");
@@ -115,6 +109,16 @@ int kobject_uevent_env(struct kobject *kobj, enum kobject_action action,
                         return 0;
                 }
 
+        /* originating subsystem */
+        if (uevent_ops && uevent_ops->name)
+                subsystem = uevent_ops->name(kset, kobj);
+        else
+                subsystem = kobject_name(&kset->kobj);
+        if (!subsystem) {
+                pr_debug("unset subsytem caused the event to drop!\n");
+                return 0;
+        }
+
         /* environment index */
         envp = kzalloc(NUM_ENVP * sizeof (char *), GFP_KERNEL);
         if (!envp)
@@ -134,12 +138,6 @@ int kobject_uevent_env(struct kobject *kobj, enum kobject_action action,
                 goto exit;
         }
 
-        /* originating subsystem */
-        if (uevent_ops && uevent_ops->name)
-                subsystem = uevent_ops->name(kset, kobj);
-        else
-                subsystem = kobject_name(&kset->kobj);
-
         /* event environemnt for helper process only */
         envp[i++] = "HOME=/";
         envp[i++] = "PATH=/sbin:/bin:/usr/sbin:/usr/bin";
diff --git a/lib/kref.c b/lib/kref.c
index 0d07cc31c818..a6dc3ec328e0 100644
--- a/lib/kref.c
+++ b/lib/kref.c
@@ -21,6 +21,7 @@
 void kref_init(struct kref *kref)
 {
         atomic_set(&kref->refcount,1);
+        smp_mb();
 }
 
 /**
@@ -31,6 +32,7 @@ void kref_get(struct kref *kref)
 {
         WARN_ON(!atomic_read(&kref->refcount));
         atomic_inc(&kref->refcount);
+        smp_mb__after_atomic_inc();
 }
 
 /**