[PATCH] fat_lock is used as a mutex, convert it to using the new mutex primitive

The fat code uses the fat_lock always in a mutex way (taking and releasing
the lock in the same function), the patch below converts it into the new
mutex primitive.  Please consider this patch for the code.

Signed-off-by: Arjan van de Ven <arjan@infradead.org>
Acked-by: OGAWA Hirofumi <hirofumi@mail.parknet.co.jp>
Cc: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

fs/fat/fatent.c

@@ -267,19 +267,19 @@ static struct fatent_operations fat32_ops = {
 
 static inline void lock_fat(struct msdos_sb_info *sbi)
 {
-	down(&sbi->fat_lock);
+	mutex_lock(&sbi->fat_lock);
 }
 
 static inline void unlock_fat(struct msdos_sb_info *sbi)
 {
-	up(&sbi->fat_lock);
+	mutex_unlock(&sbi->fat_lock);
 }
 
 void fat_ent_access_init(struct super_block *sb)
 {
 	struct msdos_sb_info *sbi = MSDOS_SB(sb);
 
-	init_MUTEX(&sbi->fat_lock);
+	mutex_init(&sbi->fat_lock);
 
 	switch (sbi->fat_bits) {
 	case 32:

include/linux/msdos_fs.h

@@ -184,6 +184,7 @@ struct fat_slot_info {
 #include <linux/string.h>
 #include <linux/nls.h>
 #include <linux/fs.h>
+#include <linux/mutex.h>
 
 struct fat_mount_options {
 	uid_t fs_uid;
@@ -226,7 +227,7 @@ struct msdos_sb_info {
 	unsigned long max_cluster;   /* maximum cluster number */
 	unsigned long root_cluster;  /* first cluster of the root directory */
 	unsigned long fsinfo_sector; /* sector number of FAT32 fsinfo */
-	struct semaphore fat_lock;
+	struct mutex fat_lock;
 	unsigned int prev_free;      /* previously allocated cluster number */
 	unsigned int free_clusters;  /* -1 if undefined */
 	struct fat_mount_options options;