cifs: display iocharset= option in /proc/mounts

...but only if it's not the default charset.

Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Steve French <smfrench@gmail.com>
diff --git a/fs/cifs/cifsfs.c b/fs/cifs/cifsfs.c
index 85ea98d..d70e551f 100644
--- a/fs/cifs/cifsfs.c
+++ b/fs/cifs/cifsfs.c
@@ -357,6 +357,18 @@
 		seq_printf(s, "loose");
 }
 
+static void
+cifs_show_nls(struct seq_file *s, struct nls_table *cur)
+{
+	struct nls_table *def;
+
+	/* Display iocharset= option if it's not default charset */
+	def = load_nls_default();
+	if (def != cur)
+		seq_printf(s, ",iocharset=%s", cur->charset);
+	unload_nls(def);
+}
+
 /*
  * cifs_show_options() is for displaying mount options in /proc/mounts.
  * Not all settable options are displayed but most of the important
@@ -418,6 +430,9 @@
 		seq_printf(s, ",file_mode=0%ho,dir_mode=0%ho",
 					   cifs_sb->mnt_file_mode,
 					   cifs_sb->mnt_dir_mode);
+
+	cifs_show_nls(s, cifs_sb->local_nls);
+
 	if (tcon->seal)
 		seq_printf(s, ",seal");
 	if (tcon->nocase)