[PATCH] sysfs_rename_dir-cleanup

o The following patch cleans up sysfs_rename_dir(). It now checks the
  return code of kobject_set_name() and propagates the error code to its
  callers. Because of this there are changes in the following two APIs. Both
  return int instead of void.

int sysfs_rename_dir(struct kobject * kobj, const char *new_name)
int kobject_rename(struct kobject * kobj, char *new_name)

drivers/base/class.c

@@ -361,6 +361,8 @@ void class_device_unregister(struct class_device *class_dev)
 
 int class_device_rename(struct class_device *class_dev, char *new_name)
 {
+	int error = 0;
+
 	class_dev = class_device_get(class_dev);
 	if (!class_dev)
 		return -EINVAL;
@@ -370,11 +372,11 @@ int class_device_rename(struct class_device *class_dev, char *new_name)
 
 	strlcpy(class_dev->class_id, new_name, KOBJ_NAME_LEN);
 
-	kobject_rename(&class_dev->kobj, new_name);
+	error = kobject_rename(&class_dev->kobj, new_name);
 
 	class_device_put(class_dev);
 
-	return 0;
+	return error;
 }
 
 struct class_device * class_device_get(struct class_device *class_dev)

fs/sysfs/dir.c

@@ -154,24 +154,33 @@ void sysfs_remove_dir(struct kobject * kobj)
 	dput(dentry);
 }
 
-void sysfs_rename_dir(struct kobject * kobj, const char *new_name)
+int sysfs_rename_dir(struct kobject * kobj, const char *new_name)
 {
+	int error = 0;
 	struct dentry * new_dentry, * parent;
 
 	if (!strcmp(kobject_name(kobj), new_name))
-		return;
+		return -EINVAL;
 
 	if (!kobj->parent)
-		return;
+		return -EINVAL;
 
 	parent = kobj->parent->dentry;
 
 	down(&parent->d_inode->i_sem);
 
 	new_dentry = sysfs_get_dentry(parent, new_name);
+	if (!IS_ERR(new_dentry)) {
+  		if (!new_dentry->d_inode) {
+			error = kobject_set_name(kobj,new_name);
+			if (!error)
 				d_move(kobj->dentry, new_dentry);
-	kobject_set_name(kobj,new_name);
+		}
+		dput(new_dentry);
+	}
 	up(&parent->d_inode->i_sem);	
+
+	return error;
 }
 
 EXPORT_SYMBOL(sysfs_create_dir);

include/linux/kobject.h

@@ -48,7 +48,7 @@ extern void kobject_cleanup(struct kobject *);
 extern int kobject_add(struct kobject *);
 extern void kobject_del(struct kobject *);
 
-extern void kobject_rename(struct kobject *, char *new_name);
+extern int kobject_rename(struct kobject *, char *new_name);
 
 extern int kobject_register(struct kobject *);
 extern void kobject_unregister(struct kobject *);

include/linux/sysfs.h

@@ -44,7 +44,7 @@ sysfs_create_dir(struct kobject *);
 extern void
 sysfs_remove_dir(struct kobject *);
 
-extern void
+extern int
 sysfs_rename_dir(struct kobject *, const char *new_name);
 
 extern int

lib/kobject.c

@@ -385,13 +385,17 @@ EXPORT_SYMBOL(kobject_set_name);
  *	@new_name: object's new name
  */
 
-void kobject_rename(struct kobject * kobj, char *new_name)
+int kobject_rename(struct kobject * kobj, char *new_name)
 {
+	int error = 0;
+
 	kobj = kobject_get(kobj);
 	if (!kobj)
-		return;
-	sysfs_rename_dir(kobj, new_name);
+		return -EINVAL;
+	error = sysfs_rename_dir(kobj, new_name);
 	kobject_put(kobj);
+
+	return error;
 }
 
 /**

net/core/dev.c

@@ -792,6 +792,8 @@ int dev_alloc_name(struct net_device *dev, const char *name)
  */
 int dev_change_name(struct net_device *dev, char *newname)
 {
+	int err = 0;
+
 	ASSERT_RTNL();
 
 	if (dev->flags & IFF_UP)
@@ -801,7 +803,7 @@ int dev_change_name(struct net_device *dev, char *newname)
 		return -EINVAL;
 
 	if (strchr(newname, '%')) {
-		int err = dev_alloc_name(dev, newname);
+		err = dev_alloc_name(dev, newname);
 		if (err < 0)
 			return err;
 		strcpy(newname, dev->name);
@@ -811,12 +813,14 @@ int dev_change_name(struct net_device *dev, char *newname)
 	else
 		strlcpy(dev->name, newname, IFNAMSIZ);
 
+	err = class_device_rename(&dev->class_dev, dev->name);
+	if (!err) {
 		hlist_del(&dev->name_hlist);
 		hlist_add_head(&dev->name_hlist, dev_name_hash(dev->name));
-
-	class_device_rename(&dev->class_dev, dev->name);
 		notifier_call_chain(&netdev_chain, NETDEV_CHANGENAME, dev);
-	return 0;
+	}
+
+	return err;
 }
 
 /**