fs: Make unload_nls() NULL pointer safe

Most call sites of unload_nls() do:
	if (nls)
		unload_nls(nls);

Check the pointer inside unload_nls() like we do in kfree() and
simplify the call sites.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Steve French <sfrench@us.ibm.com>
Cc: OGAWA Hirofumi <hirofumi@mail.parknet.co.jp>
Cc: Roman Zippel <zippel@linux-m68k.org>
Cc: Dave Kleikamp <shaggy@linux.vnet.ibm.com>
Cc: Petr Vandrovec <vandrove@vc.cvut.cz>
Cc: Anton Altaparmakov <aia21@cantab.net>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

1 files changed, 4 insertions, 12 deletions

diff --git a/fs/fat/inode.c b/fs/fat/inode.c
index 8970d8c49bb0..04629d1302fc 100644
--- a/fs/fat/inode.c
+++ b/fs/fat/inode.c
@@ -470,19 +470,11 @@ static void fat_put_super(struct super_block *sb)
 
         iput(sbi->fat_inode);
 
-        if (sbi->nls_disk) {
-                unload_nls(sbi->nls_disk);
-                sbi->nls_disk = NULL;
-                sbi->options.codepage = fat_default_codepage;
-        }
-        if (sbi->nls_io) {
-                unload_nls(sbi->nls_io);
-                sbi->nls_io = NULL;
-        }
-        if (sbi->options.iocharset != fat_default_iocharset) {
+        unload_nls(sbi->nls_disk);
+        unload_nls(sbi->nls_io);
+
+        if (sbi->options.iocharset != fat_default_iocharset)
                 kfree(sbi->options.iocharset);
-                sbi->options.iocharset = fat_default_iocharset;
-        }
 
         sb->s_fs_info = NULL;
         kfree(sbi);