This patch converts the superblock-lock semaphore to a mutex, affecting
lock_super()/unlock_super(). Tested on ext3 and XFS.
Signed-off-by: Ingo Molnar <mingo@elte.hu>
 
 static void ext3_write_super (struct super_block * sb)
 {
-       if (down_trylock(&sb->s_lock) == 0)
+       if (mutex_trylock(&sb->s_lock) != 0)
                BUG();
        sb->s_dirt = 0;
 }
 
  */
 static void ocfs2_write_super(struct super_block *sb)
 {
-       if (down_trylock(&sb->s_lock) == 0)
+       if (mutex_trylock(&sb->s_lock) != 0)
                BUG();
        sb->s_dirt = 0;
 }
 
                INIT_HLIST_HEAD(&s->s_anon);
                INIT_LIST_HEAD(&s->s_inodes);
                init_rwsem(&s->s_umount);
-               sema_init(&s->s_lock, 1);
+               mutex_init(&s->s_lock);
                down_write(&s->s_umount);
                s->s_count = S_BIAS;
                atomic_set(&s->s_active, 1);
 
        unsigned long           s_magic;
        struct dentry           *s_root;
        struct rw_semaphore     s_umount;
-       struct semaphore        s_lock;
+       struct mutex            s_lock;
        int                     s_count;
        int                     s_syncing;
        int                     s_need_sync_fs;
 static inline void lock_super(struct super_block * sb)
 {
        get_fs_excl();
-       down(&sb->s_lock);
+       mutex_lock(&sb->s_lock);
 }
 
 static inline void unlock_super(struct super_block * sb)
 {
        put_fs_excl();
-       up(&sb->s_lock);
+       mutex_unlock(&sb->s_lock);
 }
 
 /*