hpfs: Convert sbi->hpfs_creation_de to mutex

sbi->hpfs_creation_de is used as mutex so make it a mutex.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Christoph Hellwig <hch@infradead.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: linux-fsdevel@vger.kernel.org
LKML-Reference: <20100907125056.228874895@linutronix.de>

diff --git a/fs/hpfs/buffer.c b/fs/hpfs/buffer.c
index eac5f96..793cb9d 100644
--- a/fs/hpfs/buffer.c
+++ b/fs/hpfs/buffer.c
@@ -14,7 +14,7 @@
 #ifdef DEBUG_LOCKS
 	printk("lock creation\n");
 #endif
-	down(&hpfs_sb(s)->hpfs_creation_de);
+	mutex_lock(&hpfs_sb(s)->hpfs_creation_de);
 }
 
 void hpfs_unlock_creation(struct super_block *s)
@@ -22,7 +22,7 @@
 #ifdef DEBUG_LOCKS
 	printk("unlock creation\n");
 #endif
-	up(&hpfs_sb(s)->hpfs_creation_de);
+	mutex_unlock(&hpfs_sb(s)->hpfs_creation_de);
 }
 
 /* Map a sector into a buffer and return pointers to it and to the buffer. */