Index: linux-2.6.27/fs/autofs4/autofs_i.h
===================================================================
--- linux-2.6.27.orig/fs/autofs4/autofs_i.h
+++ linux-2.6.27/fs/autofs4/autofs_i.h
@@ -21,6 +21,8 @@
 #define AUTOFS_IOC_FIRST     AUTOFS_IOC_READY
 #define AUTOFS_IOC_COUNT     32
 
+#define AUTOFS_TYPE_TRIGGER	(AUTOFS_TYPE_DIRECT|AUTOFS_TYPE_OFFSET)
+
 #include <linux/kernel.h>
 #include <linux/slab.h>
 #include <linux/time.h>
@@ -92,10 +94,6 @@ struct autofs_wait_queue {
 
 #define AUTOFS_SBI_MAGIC 0x6d4a556d
 
-#define AUTOFS_TYPE_INDIRECT     0x0001
-#define AUTOFS_TYPE_DIRECT       0x0002
-#define AUTOFS_TYPE_OFFSET       0x0004
-
 struct autofs_sb_info {
 	u32 magic;
 	int pipefd;
Index: linux-2.6.27/fs/autofs4/expire.c
===================================================================
--- linux-2.6.27.orig/fs/autofs4/expire.c
+++ linux-2.6.27/fs/autofs4/expire.c
@@ -56,12 +56,23 @@ static int autofs4_mount_busy(struct vfs
 	mntget(mnt);
 	dget(dentry);
 
-	if (!autofs4_follow_mount(&mnt, &dentry))
+	if (!follow_down(&mnt, &dentry))
 		goto done;
 
-	/* This is an autofs submount, we can't expire it */
-	if (is_autofs4_dentry(dentry))
-		goto done;
+	if (is_autofs4_dentry(dentry)) {
+		struct autofs_sb_info *sbi = autofs4_sbi(dentry->d_sb);
+
+		/* This is an autofs submount, we can't expire it */
+		if (sbi->type == AUTOFS_TYPE_INDIRECT)
+			goto done;
+
+		/*
+		 * Otherwise it's an offset mount and we need to check
+		 * if we can umount its mount, if there is one.
+		 */
+		if (!d_mountpoint(dentry))
+			goto done;
+	}
 
 	/* Update the expiry counter if fs is busy */
 	if (!may_umount_tree(mnt)) {
@@ -479,7 +490,7 @@ int autofs4_expire_multi(struct super_bl
 	if (arg && get_user(do_now, arg))
 		return -EFAULT;
 
-	if (sbi->type & AUTOFS_TYPE_DIRECT)
+	if (sbi->type & AUTOFS_TYPE_TRIGGER)
 		dentry = autofs4_expire_direct(sb, mnt, sbi, do_now);
 	else
 		dentry = autofs4_expire_indirect(sb, mnt, sbi, do_now);
Index: linux-2.6.27/fs/autofs4/inode.c
===================================================================
--- linux-2.6.27.orig/fs/autofs4/inode.c
+++ linux-2.6.27/fs/autofs4/inode.c
@@ -288,7 +288,7 @@ static int parse_options(char *options, 
 			*type = AUTOFS_TYPE_DIRECT;
 			break;
 		case Opt_offset:
-			*type = AUTOFS_TYPE_DIRECT | AUTOFS_TYPE_OFFSET;
+			*type = AUTOFS_TYPE_OFFSET;
 			break;
 		default:
 			return 1;
@@ -336,7 +336,7 @@ int autofs4_fill_super(struct super_bloc
 	sbi->sb = s;
 	sbi->version = 0;
 	sbi->sub_version = 0;
-	sbi->type = 0;
+	sbi->type = AUTOFS_TYPE_INDIRECT;
 	sbi->min_proto = 0;
 	sbi->max_proto = 0;
 	mutex_init(&sbi->wq_mutex);
@@ -378,7 +378,7 @@ int autofs4_fill_super(struct super_bloc
 	}
 
 	root_inode->i_fop = &autofs4_root_operations;
-	root_inode->i_op = sbi->type & AUTOFS_TYPE_DIRECT ?
+	root_inode->i_op = sbi->type & AUTOFS_TYPE_TRIGGER ?
 			&autofs4_direct_root_inode_operations :
 			&autofs4_indirect_root_inode_operations;
 
Index: linux-2.6.27/fs/autofs4/waitq.c
===================================================================
--- linux-2.6.27.orig/fs/autofs4/waitq.c
+++ linux-2.6.27/fs/autofs4/waitq.c
@@ -337,7 +337,7 @@ int autofs4_wait(struct autofs_sb_info *
 		 * is very similar for indirect mounts except only dentrys
 		 * in the root of the autofs file system may be negative.
 		 */
-		if (sbi->type & (AUTOFS_TYPE_DIRECT|AUTOFS_TYPE_OFFSET))
+		if (sbi->type & AUTOFS_TYPE_TRIGGER)
 			return -ENOENT;
 		else if (!IS_ROOT(dentry->d_parent))
 			return -ENOENT;
@@ -348,7 +348,7 @@ int autofs4_wait(struct autofs_sb_info *
 		return -ENOMEM;
 
 	/* If this is a direct mount request create a dummy name */
-	if (IS_ROOT(dentry) && (sbi->type & AUTOFS_TYPE_DIRECT))
+	if (IS_ROOT(dentry) && sbi->type & AUTOFS_TYPE_TRIGGER)
 		qstr.len = sprintf(name, "%p", dentry);
 	else {
 		qstr.len = autofs4_getpath(sbi, dentry, &name);
@@ -406,11 +406,11 @@ int autofs4_wait(struct autofs_sb_info *
 				type = autofs_ptype_expire_multi;
 		} else {
 			if (notify == NFY_MOUNT)
-				type = (sbi->type & AUTOFS_TYPE_DIRECT) ?
+				type = (sbi->type & AUTOFS_TYPE_TRIGGER) ?
 					autofs_ptype_missing_direct :
 					 autofs_ptype_missing_indirect;
 			else
-				type = (sbi->type & AUTOFS_TYPE_DIRECT) ?
+				type = (sbi->type & AUTOFS_TYPE_TRIGGER) ?
 					autofs_ptype_expire_direct :
 					autofs_ptype_expire_indirect;
 		}
Index: linux-2.6.27/include/linux/auto_fs4.h
===================================================================
--- linux-2.6.27.orig/include/linux/auto_fs4.h
+++ linux-2.6.27/include/linux/auto_fs4.h
@@ -29,6 +29,11 @@
 #define AUTOFS_EXP_IMMEDIATE		1
 #define AUTOFS_EXP_LEAVES		2
 
+#define AUTOFS_TYPE_ANY			0x0000
+#define AUTOFS_TYPE_INDIRECT		0x0001
+#define AUTOFS_TYPE_DIRECT		0x0002
+#define AUTOFS_TYPE_OFFSET		0x0004
+
 /* Daemon notification packet types */
 enum autofs_notify {
 	NFY_NONE,