autofs: use IS_ROOT to replace root dentry checks

Use the helper macro !IS_ROOT to replace parent != dentry->d_parent.  Just
clean up.

Signed-off-by: Rui Xiang <rui.xiang@huawei.com>
Signed-off-by: Ian Kent <raven@themaw.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

fs/autofs4/root.c

@@ -558,7 +558,7 @@ static int autofs4_dir_symlink(struct inode *dir,
 	dget(dentry);
 	atomic_inc(&ino->count);
 	p_ino = autofs4_dentry_ino(dentry->d_parent);
-	if (p_ino && dentry->d_parent != dentry)
+	if (p_ino && !IS_ROOT(dentry))
 		atomic_inc(&p_ino->count);
 
 	dir->i_mtime = CURRENT_TIME;
@@ -593,7 +593,7 @@ static int autofs4_dir_unlink(struct inode *dir, struct dentry *dentry)
 
 	if (atomic_dec_and_test(&ino->count)) {
 		p_ino = autofs4_dentry_ino(dentry->d_parent);
-		if (p_ino && dentry->d_parent != dentry)
+		if (p_ino && !IS_ROOT(dentry))
 			atomic_dec(&p_ino->count);
 	}
 	dput(ino->dentry);
@@ -732,7 +732,7 @@ static int autofs4_dir_mkdir(struct inode *dir, struct dentry *dentry, umode_t m
 	dget(dentry);
 	atomic_inc(&ino->count);
 	p_ino = autofs4_dentry_ino(dentry->d_parent);
-	if (p_ino && dentry->d_parent != dentry)
+	if (p_ino && !IS_ROOT(dentry))
 		atomic_inc(&p_ino->count);
 	inc_nlink(dir);
 	dir->i_mtime = CURRENT_TIME;