4 files changed, 35 insertions, 24 deletions

diff --git a/fs/configfs/dir.c b/fs/configfs/dir.c
index 9a37a9b..5ef72c8 100644
--- a/fs/configfs/dir.c
+++ b/fs/configfs/dir.c
@@ -56,10 +56,19 @@ static void configfs_d_iput(struct dentry * dentry,
 	struct configfs_dirent *sd = dentry->d_fsdata;
 
 	if (sd) {
-		BUG_ON(sd->s_dentry != dentry);
 		/* Coordinate with configfs_readdir */
 		spin_lock(&configfs_dirent_lock);
-		sd->s_dentry = NULL;
+		/* Coordinate with configfs_attach_attr where will increase
+		 * sd->s_count and update sd->s_dentry to new allocated one.
+		 * Only set sd->dentry to null when this dentry is the only
+		 * sd owner.
+		 * If not do so, configfs_d_iput may run just after
+		 * configfs_attach_attr and set sd->s_dentry to null
+		 * even it's still in use.
+		 */
+		if (atomic_read(&sd->s_count) <= 2)
+			sd->s_dentry = NULL;
+
 		spin_unlock(&configfs_dirent_lock);
 		configfs_put(sd);
 	}
@@ -436,8 +445,11 @@ static int configfs_attach_attr(struct configfs_dirent * sd, struct dentry * den
 	struct configfs_attribute * attr = sd->s_element;
 	int error;
 
+	spin_lock(&configfs_dirent_lock);
 	dentry->d_fsdata = configfs_get(sd);
 	sd->s_dentry = dentry;
+	spin_unlock(&configfs_dirent_lock);
+
 	error = configfs_create(dentry, (attr->ca_mode & S_IALLUGO) | S_IFREG,
 				configfs_init_file);
 	if (error) {
diff --git a/fs/configfs/inode.c b/fs/configfs/inode.c
index c83f476..9d8715c 100644
--- a/fs/configfs/inode.c
+++ b/fs/configfs/inode.c
@@ -23,7 +23,8 @@
  *
  * configfs Copyright (C) 2005 Oracle.  All rights reserved.
  *
- * Please see Documentation/filesystems/configfs.txt for more information.
+ * Please see Documentation/filesystems/configfs/configfs.txt for more
+ * information.
  */
 
 #undef DEBUG
@@ -291,7 +292,7 @@ int __init configfs_inode_init(void)
 	return bdi_init(&configfs_backing_dev_info);
 }
 
-void __exit configfs_inode_exit(void)
+void configfs_inode_exit(void)
 {
 	bdi_destroy(&configfs_backing_dev_info);
 }
diff --git a/fs/configfs/item.c b/fs/configfs/item.c
index 76dc4c3..50cee7f 100644
--- a/fs/configfs/item.c
+++ b/fs/configfs/item.c
@@ -23,7 +23,7 @@
  *
  * configfs Copyright (C) 2005 Oracle.  All rights reserved.
  *
- * Please see the file Documentation/filesystems/configfs.txt for
+ * Please see the file Documentation/filesystems/configfs/configfs.txt for
  * critical information about using the config_item interface.
  */
 
diff --git a/fs/configfs/mount.c b/fs/configfs/mount.c
index ecc6217..276e15c 100644
--- a/fs/configfs/mount.c
+++ b/fs/configfs/mount.c
@@ -143,28 +143,26 @@ static int __init configfs_init(void)
 		goto out;
 
 	config_kobj = kobject_create_and_add("config", kernel_kobj);
-	if (!config_kobj) {
-		kmem_cache_destroy(configfs_dir_cachep);
-		configfs_dir_cachep = NULL;
-		goto out;
-	}
+	if (!config_kobj)
+		goto out2;
+
+	err = configfs_inode_init();
+	if (err)
+		goto out3;
 
 	err = register_filesystem(&configfs_fs_type);
-	if (err) {
-		printk(KERN_ERR "configfs: Unable to register filesystem!\n");
-		kobject_put(config_kobj);
-		kmem_cache_destroy(configfs_dir_cachep);
-		configfs_dir_cachep = NULL;
-		goto out;
-	}
+	if (err)
+		goto out4;
 
-	err = configfs_inode_init();
-	if (err) {
-		unregister_filesystem(&configfs_fs_type);
-		kobject_put(config_kobj);
-		kmem_cache_destroy(configfs_dir_cachep);
-		configfs_dir_cachep = NULL;
-	}
+	return 0;
+out4:
+	printk(KERN_ERR "configfs: Unable to register filesystem!\n");
+	configfs_inode_exit();
+out3:
+	kobject_put(config_kobj);
+out2:
+	kmem_cache_destroy(configfs_dir_cachep);
+	configfs_dir_cachep = NULL;
 out:
 	return err;
 }