[PATCH 1/8] vfs: remove lock and unlock functions for super block

[Marco Stornelli <marco.stornelli@gmail.com>]

From: Marco Stornelli <marco.stornelli@gmail.com>

Remove lock_super and unlock_super from VFS.

Signed-off-by: Marco Stornelli <marco.stornelli@gmail.com>
---

diff -Nurp linux-3.6-rc1-orig/fs/super.c linux-3.6-rc1/fs/super.c
--- linux-3.6-rc1-orig/fs/super.c	2012-08-16 09:37:35.000000000 +0200
+++ linux-3.6-rc1/fs/super.c	2012-08-16 09:43:46.000000000 +0200
@@ -186,15 +186,8 @@ static struct super_block *alloc_super(s
 		spin_lock_init(&s->s_inode_lru_lock);
 		INIT_LIST_HEAD(&s->s_mounts);
 		init_rwsem(&s->s_umount);
-		mutex_init(&s->s_lock);
 		lockdep_set_class(&s->s_umount, &type->s_umount_key);
 		/*
-		 * The locking rules for s_lock are up to the
-		 * filesystem. For example ext3fs has different
-		 * lock ordering than usbfs:
-		 */
-		lockdep_set_class(&s->s_lock, &type->s_lock_key);
-		/*
 		 * sget() can have s_umount recursion.
 		 *
 		 * When it cannot find a suitable sb, it allocates a new
@@ -400,22 +393,6 @@ bool grab_super_passive(struct super_blo
 	return false;
 }
 -/*
- * Superblock locking.  We really ought to get rid of these two.
- */
-void lock_super(struct super_block * sb)
-{
-	mutex_lock(&sb->s_lock);
-}
-
-void unlock_super(struct super_block * sb)
-{
-	mutex_unlock(&sb->s_lock);
-}
-
-EXPORT_SYMBOL(lock_super);
-EXPORT_SYMBOL(unlock_super);
-
 /**
  *	generic_shutdown_super	-	common helper for ->kill_sb()
  *	@sb: superblock to kill

diff -Nurp linux-3.6-rc1-orig/include/linux/fs.h linux-3.6-rc1/include/linux/fs.h
--- linux-3.6-rc1-orig/include/linux/fs.h	2012-08-16 11:38:42.000000000 +0200
+++ linux-3.6-rc1/include/linux/fs.h	2012-08-16 09:45:18.000000000 +0200
@@ -1504,7 +1504,6 @@ struct super_block {
 	unsigned long		s_magic;
 	struct dentry		*s_root;
 	struct rw_semaphore	s_umount;
-	struct mutex		s_lock;
 	int			s_count;
 	atomic_t		s_active;
 #ifdef CONFIG_SECURITY