1 files changed, 17 insertions, 12 deletions

diff --git a/fs/configfs/dir.c b/fs/configfs/dir.c
index b0fbcbeb03ee..54c59a7e37ce 100644
--- a/fs/configfs/dir.c
+++ b/fs/configfs/dir.c
@@ -1079,6 +1079,7 @@ int configfs_depend_item(struct configfs_subsystem *subsys,
         int ret;
         struct configfs_dirent *p, *root_sd, *subsys_sd = NULL;
         struct config_item *s_item = &subsys->su_group.cg_item;
+        struct dentry *root;
 
         /*
          * Pin the configfs filesystem.  This means we can safely access
@@ -1093,9 +1094,10 @@ int configfs_depend_item(struct configfs_subsystem *subsys,
          * subsystem is really registered, and so we need to lock out
          * configfs_[un]register_subsystem().
          */
-        mutex_lock(&configfs_sb->s_root->d_inode->i_mutex);
+        root = configfs_mount->mnt_root;
+        mutex_lock(&root->d_inode->i_mutex);
 
-        root_sd = configfs_sb->s_root->d_fsdata;
+        root_sd = root->d_fsdata;
 
         list_for_each_entry(p, &root_sd->s_children, s_sibling) {
                 if (p->s_type & CONFIGFS_DIR) {
@@ -1129,7 +1131,7 @@ int configfs_depend_item(struct configfs_subsystem *subsys,
 out_unlock_dirent_lock:
         spin_unlock(&configfs_dirent_lock);
 out_unlock_fs:
-        mutex_unlock(&configfs_sb->s_root->d_inode->i_mutex);
+        mutex_unlock(&root->d_inode->i_mutex);
 
         /*
          * If we succeeded, the fs is pinned via other methods.  If not,
@@ -1543,6 +1545,7 @@ static inline unsigned char dt_type(struct configfs_dirent *sd)
 static int configfs_readdir(struct file * filp, void * dirent, filldir_t filldir)
 {
         struct dentry *dentry = filp->f_path.dentry;
+        struct super_block *sb = dentry->d_sb;
         struct configfs_dirent * parent_sd = dentry->d_fsdata;
         struct configfs_dirent *cursor = filp->private_data;
         struct list_head *p, *q = &cursor->s_sibling;
@@ -1605,7 +1608,7 @@ static int configfs_readdir(struct file * filp, void * dirent, filldir_t filldir
                                         ino = inode->i_ino;
                                 spin_unlock(&configfs_dirent_lock);
                                 if (!inode)
-                                        ino = iunique(configfs_sb, 2);
+                                        ino = iunique(sb, 2);
 
                                 if (filldir(dirent, name, len, filp->f_pos, ino,
                                                  dt_type(next)) < 0)
@@ -1677,6 +1680,7 @@ int configfs_register_subsystem(struct configfs_subsystem *subsys)
         struct config_group *group = &subsys->su_group;
         struct qstr name;
         struct dentry *dentry;
+        struct dentry *root;
         struct configfs_dirent *sd;
 
         err = configfs_pin_fs();
@@ -1686,18 +1690,18 @@ int configfs_register_subsystem(struct configfs_subsystem *subsys)
         if (!group->cg_item.ci_name)
                 group->cg_item.ci_name = group->cg_item.ci_namebuf;
 
-        sd = configfs_sb->s_root->d_fsdata;
+        root = configfs_mount->mnt_root;
+        sd = root->d_fsdata;
         link_group(to_config_group(sd->s_element), group);
 
-        mutex_lock_nested(&configfs_sb->s_root->d_inode->i_mutex,
-                        I_MUTEX_PARENT);
+        mutex_lock_nested(&root->d_inode->i_mutex, I_MUTEX_PARENT);
 
         name.name = group->cg_item.ci_name;
         name.len = strlen(name.name);
         name.hash = full_name_hash(name.name, name.len);
 
         err = -ENOMEM;
-        dentry = d_alloc(configfs_sb->s_root, &name);
+        dentry = d_alloc(root, &name);
         if (dentry) {
                 d_add(dentry, NULL);
 
@@ -1714,7 +1718,7 @@ int configfs_register_subsystem(struct configfs_subsystem *subsys)
                 }
         }
 
-        mutex_unlock(&configfs_sb->s_root->d_inode->i_mutex);
+        mutex_unlock(&root->d_inode->i_mutex);
 
         if (err) {
                 unlink_group(group);
@@ -1728,13 +1732,14 @@ void configfs_unregister_subsystem(struct configfs_subsystem *subsys)
 {
         struct config_group *group = &subsys->su_group;
         struct dentry *dentry = group->cg_item.ci_dentry;
+        struct dentry *root = dentry->d_sb->s_root;
 
-        if (dentry->d_parent != configfs_sb->s_root) {
+        if (dentry->d_parent != root) {
                 printk(KERN_ERR "configfs: Tried to unregister non-subsystem!\n");
                 return;
         }
 
-        mutex_lock_nested(&configfs_sb->s_root->d_inode->i_mutex,
+        mutex_lock_nested(&root->d_inode->i_mutex,
                           I_MUTEX_PARENT);
         mutex_lock_nested(&dentry->d_inode->i_mutex, I_MUTEX_CHILD);
         mutex_lock(&configfs_symlink_mutex);
@@ -1751,7 +1756,7 @@ void configfs_unregister_subsystem(struct configfs_subsystem *subsys)
 
         d_delete(dentry);
 
-        mutex_unlock(&configfs_sb->s_root->d_inode->i_mutex);
+        mutex_unlock(&root->d_inode->i_mutex);
 
         dput(dentry);