BKL: Remove BKL from fat

The lock_kernel in fat_put_super is not needed because
it only protects the super block itself and we know that
no other thread can reach it because we are about to
kfree the object.

In the two fill_super functions, this converts the locking
to use lock_super like elsewhere in the fat code. This
is probably not needed either, but is consistent and puts
us on the safe side.
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Cc: OGAWA Hirofumi <hirofumi@mail.parknet.co.jp>
Cc: Jan Blunck <jblunck@infradead.org>

fs/fat/inode.c

@@ -14,7 +14,6 @@
 #include <linux/init.h>
 #include <linux/time.h>
 #include <linux/slab.h>
-#include <linux/smp_lock.h>
 #include <linux/seq_file.h>
 #include <linux/pagemap.h>
 #include <linux/mpage.h>
@@ -489,8 +488,6 @@ static void fat_put_super(struct super_block *sb)
 {
 	struct msdos_sb_info *sbi = MSDOS_SB(sb);
 
-	lock_kernel();
-
 	if (sb->s_dirt)
 		fat_write_super(sb);
 
@@ -504,8 +501,6 @@ static void fat_put_super(struct super_block *sb)
 
 	sb->s_fs_info = NULL;
 	kfree(sbi);
-
-	unlock_kernel();
 }
 
 static struct kmem_cache *fat_inode_cachep;

fs/fat/namei_msdos.c

@@ -9,7 +9,6 @@
 #include <linux/module.h>
 #include <linux/time.h>
 #include <linux/buffer_head.h>
-#include <linux/smp_lock.h>     /* For lock_kernel() */
 #include "fat.h"
 
 /* Characters that are undesirable in an MS-DOS file name */
@@ -663,16 +662,16 @@ static int msdos_fill_super(struct super_block *sb, void *data, int silent)
 {
 	int res;
 
-	lock_kernel();
+	lock_super(sb);
 	res = fat_fill_super(sb, data, silent, &msdos_dir_inode_operations, 0);
 	if (res) {
-		unlock_kernel();
+		unlock_super(sb);
 		return res;
 	}
 
 	sb->s_flags |= MS_NOATIME;
 	sb->s_root->d_op = &msdos_dentry_operations;
-	unlock_kernel();
+	unlock_super(sb);
 	return 0;
 }
 

fs/fat/namei_vfat.c

@@ -21,7 +21,6 @@
 #include <linux/slab.h>
 #include <linux/buffer_head.h>
 #include <linux/namei.h>
-#include <linux/smp_lock.h>     /* For lock_kernel() */
 #include "fat.h"
 
 /*
@@ -1056,10 +1055,10 @@ static int vfat_fill_super(struct super_block *sb, void *data, int silent)
 {
 	int res;
 
-	lock_kernel();
+	lock_super(sb);
 	res = fat_fill_super(sb, data, silent, &vfat_dir_inode_operations, 1);
 	if (res) {
-		unlock_kernel();
+		unlock_super(sb);
 		return res;
 	}
 
@@ -1068,7 +1067,7 @@ static int vfat_fill_super(struct super_block *sb, void *data, int silent)
 	else
 		sb->s_root->d_op = &vfat_dentry_ops;
 
-	unlock_kernel();
+	unlock_super(sb);
 	return 0;
 }