vfs: switch ->show_options() to struct dentry *

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
diff --git a/fs/nilfs2/super.c b/fs/nilfs2/super.c
index 5356c71..08e3d4f 100644
--- a/fs/nilfs2/super.c
+++ b/fs/nilfs2/super.c
@@ -648,11 +648,11 @@
 	return 0;
 }
 
-static int nilfs_show_options(struct seq_file *seq, struct vfsmount *vfs)
+static int nilfs_show_options(struct seq_file *seq, struct dentry *dentry)
 {
-	struct super_block *sb = vfs->mnt_sb;
+	struct super_block *sb = dentry->d_sb;
 	struct the_nilfs *nilfs = sb->s_fs_info;
-	struct nilfs_root *root = NILFS_I(vfs->mnt_root->d_inode)->i_root;
+	struct nilfs_root *root = NILFS_I(dentry->d_inode)->i_root;
 
 	if (!nilfs_test_opt(nilfs, BARRIER))
 		seq_puts(seq, ",nobarrier");