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Sophie

distrib > Scientific%20Linux > 5x > x86_64 > by-pkgid > 1c532bdd6a38c500faa1c4918a0301ca > files > 55

autofs-5.0.1-0.rc2.184.el5.x86_64.rpm

diff -Nurp linux-2.6.9.orig/fs/autofs/dirhash.c linux-2.6.9/fs/autofs/dirhash.c
--- linux-2.6.9.orig/fs/autofs/dirhash.c	2004-10-19 05:53:12.000000000 +0800
+++ linux-2.6.9/fs/autofs/dirhash.c	2006-08-31 12:14:13.000000000 +0800
@@ -92,7 +92,7 @@ struct autofs_dir_ent *autofs_expire(str
 			;
 		dput(dentry);
 
-		if ( may_umount(mnt) == 0 ) {
+		if ( may_umount(mnt) ) {
 			mntput(mnt);
 			DPRINTK(("autofs: signaling expire on %s\n", ent->name));
 			return ent; /* Expirable! */
diff -Nurp linux-2.6.9.orig/fs/autofs4/autofs_i.h linux-2.6.9/fs/autofs4/autofs_i.h
--- linux-2.6.9.orig/fs/autofs4/autofs_i.h	2004-10-19 05:54:38.000000000 +0800
+++ linux-2.6.9/fs/autofs4/autofs_i.h	2006-08-31 12:14:13.000000000 +0800
@@ -3,6 +3,7 @@
  * linux/fs/autofs/autofs_i.h
  *
  *   Copyright 1997-1998 Transmeta Corporation - All Rights Reserved
+ *   Copyright 2005-2006 Ian Kent <raven@themaw.net>
  *
  * This file is part of the Linux kernel and is made available under
  * the terms of the GNU General Public License, version 2, or at your
@@ -40,14 +41,6 @@
 
 #define AUTOFS_SUPER_MAGIC 0x0187
 
-/*
- * If the daemon returns a negative response (AUTOFS_IOC_FAIL) then the
- * kernel will keep the negative response cached for up to the time given
- * here, although the time can be shorter if the kernel throws the dcache
- * entry away.  This probably should be settable from user space.
- */
-#define AUTOFS_NEGATIVE_TIMEOUT (60*HZ)	/* 1 minute */
-
 /* Unified info structure.  This is pointed to by both the dentry and
    inode structures.  Each file in the filesystem has an instance of this
    structure.  It holds a reference to the dentry, so dentries are never
@@ -62,6 +55,7 @@ struct autofs_info {
 
 	struct autofs_sb_info *sbi;
 	unsigned long last_used;
+	atomic_t count;
 
 	mode_t	mode;
 	size_t	size;
@@ -79,9 +73,15 @@ struct autofs_wait_queue {
 	struct autofs_wait_queue *next;
 	autofs_wqt_t wait_queue_token;
 	/* We use the following to see what we are waiting for */
-	int hash;
-	int len;
+	unsigned int hash;
+	unsigned int len;
 	char *name;
+	u32 dev;
+	u64 ino;
+	uid_t uid;
+	gid_t gid;
+	pid_t pid;
+	pid_t tgid;
 	/* This is for status reporting upon return */
 	int status;
 	atomic_t wait_ctr;
@@ -89,18 +89,28 @@ 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;
+	struct dentry *root;
+	int pipefd;
 	struct file *pipe;
 	pid_t oz_pgrp;
 	int catatonic;
 	int version;
 	int sub_version;
+	int min_proto;
+	int max_proto;
 	unsigned long exp_timeout;
+	unsigned int type;
 	int reghost_enabled;
 	int needs_reghost;
 	struct super_block *sb;
 	struct semaphore wq_sem;
+	spinlock_t fs_lock;
 	struct autofs_wait_queue *queues; /* Wait queue pointer */
 };
 
@@ -126,9 +136,18 @@ static inline int autofs4_oz_mode(struct
 static inline int autofs4_ispending(struct dentry *dentry)
 {
 	struct autofs_info *inf = autofs4_dentry_ino(dentry);
+	int pending = 0;
+
+	if (dentry->d_flags & DCACHE_AUTOFS_PENDING)
+		return 1;
 
-	return (dentry->d_flags & DCACHE_AUTOFS_PENDING) ||
-		(inf != NULL && inf->flags & AUTOFS_INF_EXPIRING);
+	if (inf) {
+		spin_lock(&inf->sbi->fs_lock);
+		pending = inf->flags & AUTOFS_INF_EXPIRING;
+		spin_unlock(&inf->sbi->fs_lock);
+	}
+
+	return pending;
 }
 
 static inline void autofs4_copy_atime(struct file *src, struct file *dst)
@@ -153,6 +172,8 @@ int autofs4_expire_multi(struct super_bl
 extern struct inode_operations autofs4_symlink_inode_operations;
 extern struct inode_operations autofs4_dir_inode_operations;
 extern struct inode_operations autofs4_root_inode_operations;
+extern struct inode_operations autofs4_indirect_root_inode_operations;
+extern struct inode_operations autofs4_direct_root_inode_operations;
 extern struct file_operations autofs4_dir_operations;
 extern struct file_operations autofs4_root_operations;
 
@@ -163,23 +184,39 @@ struct autofs_info *autofs4_init_ino(str
 
 /* Queue management functions */
 
-enum autofs_notify
-{
-	NFY_NONE,
-	NFY_MOUNT,
-	NFY_EXPIRE
-};
-
 int autofs4_wait(struct autofs_sb_info *,struct dentry *, enum autofs_notify);
 int autofs4_wait_release(struct autofs_sb_info *,autofs_wqt_t,int);
 void autofs4_catatonic_mode(struct autofs_sb_info *);
 
+static inline int autofs4_follow_mount(struct vfsmount **mnt, struct dentry **dentry)
+{
+	int res = 0;
+
+	while (d_mountpoint(*dentry)) {
+		int followed = follow_down(mnt, dentry);
+		if (!followed)
+			break;
+		res = 1;
+	}
+	return res;
+}
+
+static inline u32 autofs4_get_dev(struct autofs_sb_info *sbi)
+{
+	return new_encode_dev(sbi->sb->s_dev);
+}
+
+static inline u64 autofs4_get_ino(struct autofs_sb_info *sbi)
+{
+	return sbi->sb->s_root->d_inode->i_ino;
+}
+
 static inline int simple_positive(struct dentry *dentry)
 {
 	return dentry->d_inode && !d_unhashed(dentry);
 }
 
-static inline int simple_empty_nolock(struct dentry *dentry)
+static inline int __simple_empty(struct dentry *dentry)
 {
 	struct dentry *child;
 	int ret = 0;
@@ -191,3 +228,6 @@ static inline int simple_empty_nolock(st
 out:
 	return ret;
 }
+
+void autofs4_dentry_release(struct dentry *);
+
diff -Nurp linux-2.6.9.orig/fs/autofs4/expire.c linux-2.6.9/fs/autofs4/expire.c
--- linux-2.6.9.orig/fs/autofs4/expire.c	2004-10-19 05:54:39.000000000 +0800
+++ linux-2.6.9/fs/autofs4/expire.c	2006-08-31 12:14:13.000000000 +0800
@@ -4,7 +4,7 @@
  *
  *  Copyright 1997-1998 Transmeta Corporation -- All Rights Reserved
  *  Copyright 1999-2000 Jeremy Fitzhardinge <jeremy@goop.org>
- *  Copyright 2001-2003 Ian Kent <raven@themaw.net>
+ *  Copyright 2001-2006 Ian Kent <raven@themaw.net>
  *
  * This file is part of the Linux kernel and is made available under
  * the terms of the GNU General Public License, version 2, or at your
@@ -16,7 +16,7 @@
 
 static unsigned long now;
 
-/* Check if a dentry can be expired return 1 if it can else return 0 */
+/* Check if a dentry can be expired */
 static inline int autofs4_can_expire(struct dentry *dentry,
 					unsigned long timeout, int do_now)
 {
@@ -41,14 +41,14 @@ static inline int autofs4_can_expire(str
 		     attempts if expire fails the first time */
 		ino->last_used = now;
 	}
-
 	return 1;
 }
 
-/* Check a mount point for busyness return 1 if not busy, otherwise */
-static int autofs4_check_mount(struct vfsmount *mnt, struct dentry *dentry)
+/* Check a mount point for busyness */
+static int autofs4_mount_busy(struct vfsmount *mnt, struct dentry *dentry)
 {
-	int status = 0;
+	struct dentry *top = dentry;
+	int status = 1;
 
 	DPRINTK("dentry %p %.*s",
 		dentry, (int)dentry->d_name.len, dentry->d_name.name);
@@ -56,19 +56,21 @@ static int autofs4_check_mount(struct vf
 	mntget(mnt);
 	dget(dentry);
 
-	if (!follow_down(&mnt, &dentry))
+	if (!autofs4_follow_mount(&mnt, &dentry))
 		goto done;
 
-	while (d_mountpoint(dentry) && follow_down(&mnt, &dentry))
-		;
-
 	/* This is an autofs submount, we can't expire it */
 	if (is_autofs4_dentry(dentry))
 		goto done;
 
-	/* The big question */
-	if (may_umount_tree(mnt) == 0)
-		status = 1;
+	/* Update the expiry counter if fs is busy */
+	if (!may_umount_tree(mnt)) {
+		struct autofs_info *ino = autofs4_dentry_ino(top);
+		ino->last_used = jiffies;
+		goto done;
+	}
+
+	status = 0;
 done:
 	DPRINTK("returning = %d", status);
 	mntput(mnt);
@@ -76,74 +78,130 @@ done:
 	return status;
 }
 
+/*
+ * Calculate next entry in top down tree traversal.
+ * From next_mnt in namespace.c - elegant.
+ */
+static struct dentry *next_dentry(struct dentry *p, struct dentry *root)
+{
+	struct list_head *next = p->d_subdirs.next;
+
+	if (next == &p->d_subdirs) {
+		while (1) {
+			if (p == root)
+				return NULL;
+			next = p->d_child.next;
+			if (next != &p->d_parent->d_subdirs)
+				break;
+			p = p->d_parent;
+		}
+	}
+	return list_entry(next, struct dentry, d_child);
+}
+
+/*
+ * Check a direct mount point for busyness.
+ * Direct mounts have similar expiry semantics to tree mounts.
+ * The tree is not busy iff no mountpoints are busy and there are no
+ * autofs submounts.
+ */
+static int autofs4_direct_busy(struct vfsmount *mnt,
+				struct dentry *top,
+				unsigned long timeout,
+				int do_now)
+{
+	DPRINTK("top %p %.*s",
+		top, (int) top->d_name.len, top->d_name.name);
+
+	/* If it's busy update the expiry counters */
+	if (!may_umount_tree(mnt)) {
+		struct autofs_info *ino = autofs4_dentry_ino(top);
+		if (ino)
+			ino->last_used = jiffies;
+		return 1;
+	}
+
+	/* Timeout of a direct mount is determined by its top dentry */
+	if (!autofs4_can_expire(top, timeout, do_now))
+		return 1;
+
+	return 0;
+}
+
 /* Check a directory tree of mount points for busyness
  * The tree is not busy iff no mountpoints are busy
- * Return 1 if the tree is busy or 0 otherwise
  */
-static int autofs4_check_tree(struct vfsmount *mnt,
-	       		      struct dentry *top,
-			      unsigned long timeout,
-			      int do_now)
+static int autofs4_tree_busy(struct vfsmount *mnt,
+	       		     struct dentry *top,
+			     unsigned long timeout,
+			     int do_now)
 {
-	struct dentry *this_parent = top;
-	struct list_head *next;
+	struct autofs_info *top_ino = autofs4_dentry_ino(top);
+	struct dentry *p;
 
-	DPRINTK("parent %p %.*s",
+	DPRINTK("top %p %.*s",
 		top, (int)top->d_name.len, top->d_name.name);
 
 	/* Negative dentry - give up */
 	if (!simple_positive(top))
-		return 0;
-
-	/* Timeout of a tree mount is determined by its top dentry */
-	if (!autofs4_can_expire(top, timeout, do_now))
-		return 0;
+		return 1;
 
 	spin_lock(&dcache_lock);
-repeat:
-	next = this_parent->d_subdirs.next;
-resume:
-	while (next != &this_parent->d_subdirs) {
-		struct dentry *dentry = list_entry(next, struct dentry, d_child);
-
+	for (p = top; p; p = next_dentry(p, top)) {
 		/* Negative dentry - give up */
-		if (!simple_positive(dentry)) {
-			next = next->next;
+		if (!simple_positive(p))
 			continue;
-		}
 
 		DPRINTK("dentry %p %.*s",
-			dentry, (int)dentry->d_name.len, dentry->d_name.name);
-
-		if (!simple_empty_nolock(dentry)) {
-			this_parent = dentry;
-			goto repeat;
-		}
+			p, (int) p->d_name.len, p->d_name.name);
 
-		dentry = dget(dentry);
+		p = dget(p);
 		spin_unlock(&dcache_lock);
 
-		if (d_mountpoint(dentry)) {
-			/* First busy => tree busy */
-			if (!autofs4_check_mount(mnt, dentry)) {
-				dput(dentry);
-				return 0;
+		/*
+		 * Is someone visiting anywhere in the subtree ?
+		 * If there's no mount we need to check the usage
+		 * count for the autofs dentry.
+		 * If the fs is busy update the expiry counter.
+		 */
+		if (d_mountpoint(p)) {
+			if (autofs4_mount_busy(mnt, p)) {
+				top_ino->last_used = jiffies;
+				dput(p);
+				return 1;
 			}
-		}
+		} else {
+			struct autofs_info *ino = autofs4_dentry_ino(p);
+			unsigned int ino_count = atomic_read(&ino->count);
 
-		dput(dentry);
+			/*
+			 * Clean stale dentries below that have not been
+			 * invalidated after a mount fail during lookup
+			 */
+			d_invalidate(p);
+
+			/* allow for dget above and top is already dgot */
+			if (p == top)
+				ino_count += 2;
+			else
+				ino_count++;
+
+			if (atomic_read(&p->d_count) > ino_count) {
+				top_ino->last_used = jiffies;
+				dput(p);
+				return 1;
+			}
+		}
+		dput(p);
 		spin_lock(&dcache_lock);
-		next = next->next;
-	}
-
-	if (this_parent != top) {
-		next = this_parent->d_child.next;
-		this_parent = this_parent->d_parent;
-		goto resume;
 	}
 	spin_unlock(&dcache_lock);
 
-	return 1;
+	/* Timeout of a tree mount is ultimately determined by its top dentry */
+	if (!autofs4_can_expire(top, timeout, do_now))
+		return 1;
+
+	return 0;
 }
 
 static struct dentry *autofs4_check_leaves(struct vfsmount *mnt,
@@ -151,58 +209,68 @@ static struct dentry *autofs4_check_leav
 					   unsigned long timeout,
 					   int do_now)
 {
-	struct dentry *this_parent = parent;
-	struct list_head *next;
+	struct dentry *p;
 
 	DPRINTK("parent %p %.*s",
 		parent, (int)parent->d_name.len, parent->d_name.name);
 
 	spin_lock(&dcache_lock);
-repeat:
-	next = this_parent->d_subdirs.next;
-resume:
-	while (next != &this_parent->d_subdirs) {
-		struct dentry *dentry = list_entry(next, struct dentry, d_child);
-
+	for (p = parent; p; p = next_dentry(p, parent)) {
 		/* Negative dentry - give up */
-		if (!simple_positive(dentry)) {
-			next = next->next;
+		if (!simple_positive(p))
 			continue;
-		}
 
 		DPRINTK("dentry %p %.*s",
-			dentry, (int)dentry->d_name.len, dentry->d_name.name);
-
-		if (!list_empty(&dentry->d_subdirs)) {
-			this_parent = dentry;
-			goto repeat;
-		}
+			p, (int) p->d_name.len, p->d_name.name);
 
-		dentry = dget(dentry);
+		p = dget(p);
 		spin_unlock(&dcache_lock);
 
-		if (d_mountpoint(dentry)) {
-			/* Can we expire this guy */
-			if (!autofs4_can_expire(dentry, timeout, do_now))
-				goto cont;
-
+		if (d_mountpoint(p)) {
 			/* Can we umount this guy */
-			if (autofs4_check_mount(mnt, dentry))
-				return dentry;
+			if (autofs4_mount_busy(mnt, p))
+				goto cont;
 
+			/* Can we expire this guy */
+			if (autofs4_can_expire(p, timeout, do_now))
+				return p;
 		}
 cont:
-		dput(dentry);
+		dput(p);
 		spin_lock(&dcache_lock);
-		next = next->next;
 	}
+	spin_unlock(&dcache_lock);
+	return NULL;
+}
+
+/* Check if we can expire a direct mount (possibly a tree) */
+static struct dentry *autofs4_expire_direct(struct super_block *sb,
+					    struct vfsmount *mnt,
+					    struct autofs_sb_info *sbi,
+					    int how)
+{
+	unsigned long timeout;
+	struct dentry *root = dget(sb->s_root);
+	int do_now = how & AUTOFS_EXP_IMMEDIATE;
+
+	if (!sbi->exp_timeout || !root)
+		return NULL;
 
-	if (this_parent != parent) {
-		next = this_parent->d_child.next;
-		this_parent = this_parent->d_parent;
-		goto resume;
+	now = jiffies;
+	timeout = sbi->exp_timeout;
+
+	/* Lock the tree as we must expire as a whole */
+	spin_lock(&sbi->fs_lock);
+	if (!autofs4_direct_busy(mnt, root, timeout, do_now)) {
+		struct autofs_info *ino = autofs4_dentry_ino(root);
+
+		/* Set this flag early to catch sys_chdir and the like */
+		ino->flags |= AUTOFS_INF_EXPIRING;
+		spin_unlock(&sbi->fs_lock);
+		return root;
 	}
-	spin_unlock(&dcache_lock);
+	spin_unlock(&sbi->fs_lock);
+	dput(root);
 
 	return NULL;
 }
@@ -213,10 +281,10 @@ cont:
  *  - it is unused by any user process
  *  - it has been unused for exp_timeout time
  */
-static struct dentry *autofs4_expire(struct super_block *sb,
-				     struct vfsmount *mnt,
-				     struct autofs_sb_info *sbi,
-				     int how)
+static struct dentry *autofs4_expire_indirect(struct super_block *sb,
+					      struct vfsmount *mnt,
+					      struct autofs_sb_info *sbi,
+					      int how)
 {
 	unsigned long timeout;
 	struct dentry *root = sb->s_root;
@@ -240,7 +308,7 @@ static struct dentry *autofs4_expire(str
 		struct dentry *dentry = list_entry(next, struct dentry, d_child);
 
 		/* Negative dentry - give up */
-		if ( !simple_positive(dentry) ) {
+		if (!simple_positive(dentry)) {
 			next = next->next;
 			continue;
 		}
@@ -248,33 +316,49 @@ static struct dentry *autofs4_expire(str
 		dentry = dget(dentry);
 		spin_unlock(&dcache_lock);
 
-		/* Case 1: indirect mount or top level direct mount */
+		/*
+		 * Case 1: (i) indirect mount or top level pseudo direct mount
+		 *	   (autofs-4.1).
+		 *	   (ii) indirect mount with offset mount, check the "/"
+		 *	   offset (autofs-5.0+).
+		 */
 		if (d_mountpoint(dentry)) {
 			DPRINTK("checking mountpoint %p %.*s",
 				dentry, (int)dentry->d_name.len, dentry->d_name.name);
 
-			/* Can we expire this guy */
-			if (!autofs4_can_expire(dentry, timeout, do_now))
+			/* Can we umount this guy */
+			if (autofs4_mount_busy(mnt, dentry))
 				goto next;
 
-			/* Can we umount this guy */
-			if (autofs4_check_mount(mnt, dentry)) {
+			/* Can we expire this guy */
+			if (autofs4_can_expire(dentry, timeout, do_now)) {
 				expired = dentry;
 				break;
 			}
 			goto next;
 		}
 
-		if ( simple_empty(dentry) )
+		if (simple_empty(dentry))
 			goto next;
 
 		/* Case 2: tree mount, expire iff entire tree is not busy */
 		if (!exp_leaves) {
-			if (autofs4_check_tree(mnt, dentry, timeout, do_now)) {
-			expired = dentry;
-			break;
+			/* Lock the tree as we must expire as a whole */
+			spin_lock(&sbi->fs_lock);
+			if (!autofs4_tree_busy(mnt, dentry, timeout, do_now)) {
+				struct autofs_info *inf = autofs4_dentry_ino(dentry);
+
+				/* Set this flag early to catch sys_chdir and the like */
+				inf->flags |= AUTOFS_INF_EXPIRING;
+				spin_unlock(&sbi->fs_lock);
+				expired = dentry;
+				break;
 			}
-		/* Case 3: direct mount, expire individual leaves */
+			spin_unlock(&sbi->fs_lock);
+		/*
+		 * Case 3: pseudo direct mount, expire individual leaves
+		 *	   (autofs-4.1).
+		 */
 		} else {
 			expired = autofs4_check_leaves(mnt, dentry, timeout, do_now);
 			if (expired) {
@@ -288,7 +372,7 @@ next:
 		next = next->next;
 	}
 
-	if ( expired ) {
+	if (expired) {
 		DPRINTK("returning %p %.*s",
 			expired, (int)expired->d_name.len, expired->d_name.name);
 		spin_lock(&dcache_lock);
@@ -316,7 +400,7 @@ int autofs4_expire_run(struct super_bloc
 	pkt.hdr.proto_version = sbi->version;
 	pkt.hdr.type = autofs_ptype_expire;
 
-	if ((dentry = autofs4_expire(sb, mnt, sbi, 0)) == NULL)
+	if ((dentry = autofs4_expire_indirect(sb, mnt, sbi, 0)) == NULL)
 		return -EAGAIN;
 
 	pkt.len = dentry->d_name.len;
@@ -342,17 +426,22 @@ int autofs4_expire_multi(struct super_bl
 	if (arg && get_user(do_now, arg))
 		return -EFAULT;
 
-	if ((dentry = autofs4_expire(sb, mnt, sbi, do_now)) != NULL) {
-		struct autofs_info *de_info = autofs4_dentry_ino(dentry);
+	if (sbi->type & AUTOFS_TYPE_DIRECT)
+		dentry = autofs4_expire_direct(sb, mnt, sbi, do_now);
+	else
+		dentry = autofs4_expire_indirect(sb, mnt, sbi, do_now);
+
+	if (dentry) {
+		struct autofs_info *ino = autofs4_dentry_ino(dentry);
 
 		/* This is synchronous because it makes the daemon a
                    little easier */
-		de_info->flags |= AUTOFS_INF_EXPIRING;
+		ino->flags |= AUTOFS_INF_EXPIRING;
 		ret = autofs4_wait(sbi, dentry, NFY_EXPIRE);
-		de_info->flags &= ~AUTOFS_INF_EXPIRING;
+		ino->flags &= ~AUTOFS_INF_EXPIRING;
 		dput(dentry);
 	}
-		
+
 	return ret;
 }
 
diff -Nurp linux-2.6.9.orig/fs/autofs4/inode.c linux-2.6.9/fs/autofs4/inode.c
--- linux-2.6.9.orig/fs/autofs4/inode.c	2004-10-19 05:54:40.000000000 +0800
+++ linux-2.6.9/fs/autofs4/inode.c	2006-08-31 12:14:13.000000000 +0800
@@ -3,6 +3,7 @@
  * linux/fs/autofs/inode.c
  *
  *  Copyright 1997-1998 Transmeta Corporation -- All Rights Reserved
+ *  Copyright 2005-2006 Ian Kent <raven@themaw.net>
  *
  * This file is part of the Linux kernel and is made available under
  * the terms of the GNU General Public License, version 2, or at your
@@ -13,9 +14,11 @@
 #include <linux/kernel.h>
 #include <linux/slab.h>
 #include <linux/file.h>
+#include <linux/seq_file.h>
 #include <linux/pagemap.h>
 #include <linux/parser.h>
 #include <asm/bitops.h>
+#include <linux/smp_lock.h>
 #include "autofs_i.h"
 #include <linux/module.h>
 
@@ -47,6 +50,7 @@ struct autofs_info *autofs4_init_ino(str
 	ino->size = 0;
 
 	ino->last_used = jiffies;
+	atomic_set(&ino->count, 0);
 
 	ino->sbi = sbi;
 
@@ -65,10 +69,19 @@ struct autofs_info *autofs4_init_ino(str
 
 void autofs4_free_ino(struct autofs_info *ino)
 {
+	struct autofs_info *p_ino;
+
 	if (ino->dentry) {
 		ino->dentry->d_fsdata = NULL;
-		if (ino->dentry->d_inode)
+		if (ino->dentry->d_inode) {
+			struct dentry *parent = ino->dentry->d_parent;
+			if (atomic_dec_and_test(&ino->count)) {
+				p_ino = autofs4_dentry_ino(parent);
+				if (p_ino && parent != ino->dentry)
+					atomic_dec(&p_ino->count);
+			}
 			dput(ino->dentry);
+		}
 		ino->dentry = NULL;
 	}
 	if (ino->free)
@@ -76,6 +89,66 @@ void autofs4_free_ino(struct autofs_info
 	kfree(ino);
 }
 
+/*
+ * Deal with the infamous "Busy inodes after umount ..." message.
+ *
+ * Clean up the dentry tree. This happens with autofs if the user
+ * space program goes away due to a SIGKILL, SIGSEGV etc.
+ */
+static void autofs4_force_release(struct autofs_sb_info *sbi)
+{
+	struct dentry *this_parent = sbi->root;
+	struct list_head *next;
+
+	spin_lock(&dcache_lock);
+repeat:
+	next = this_parent->d_subdirs.next;
+resume:
+	while (next != &this_parent->d_subdirs) {
+		struct dentry *dentry = list_entry(next, struct dentry, d_child);
+
+		/* Negative dentry - don`t care */
+		if (!simple_positive(dentry)) {
+			next = next->next;
+			continue;
+		}
+
+		if (!list_empty(&dentry->d_subdirs)) {
+			this_parent = dentry;
+			goto repeat;
+		}
+
+		next = next->next;
+		spin_unlock(&dcache_lock);
+
+		DPRINTK("dentry %p %.*s",
+			dentry, (int)dentry->d_name.len, dentry->d_name.name);
+
+		dput(dentry);
+		spin_lock(&dcache_lock);
+	}
+
+	if (this_parent != sbi->root) {
+		struct dentry *dentry = this_parent;
+
+		next = this_parent->d_child.next;
+		this_parent = this_parent->d_parent;
+		spin_unlock(&dcache_lock);
+		DPRINTK("parent dentry %p %.*s",
+			dentry, (int)dentry->d_name.len, dentry->d_name.name);
+		dput(dentry);
+		spin_lock(&dcache_lock);
+		goto resume;
+	}
+	spin_unlock(&dcache_lock);
+
+	dput(sbi->root);
+	sbi->root = NULL;
+	shrink_dcache_sb(sbi->sb);
+
+	return;
+}
+
 static void autofs4_put_super(struct super_block *sb)
 {
 	struct autofs_sb_info *sbi = autofs4_sbi(sb);
@@ -85,17 +158,45 @@ static void autofs4_put_super(struct sup
 	if ( !sbi->catatonic )
 		autofs4_catatonic_mode(sbi); /* Free wait queues, close pipe */
 
+	/* Clean up and release dangling references */
+	autofs4_force_release(sbi);
+
 	kfree(sbi);
 
 	DPRINTK("shutting down");
 }
 
+static int autofs4_show_options(struct seq_file *m, struct vfsmount *mnt)
+{
+	struct autofs_sb_info *sbi = autofs4_sbi(mnt->mnt_sb);
+
+	if (!sbi)
+		return 0;
+
+	seq_printf(m, ",fd=%d", sbi->pipefd);
+	seq_printf(m, ",pgrp=%d", sbi->oz_pgrp);
+	seq_printf(m, ",timeout=%lu", sbi->exp_timeout/HZ);
+	seq_printf(m, ",minproto=%d", sbi->min_proto);
+	seq_printf(m, ",maxproto=%d", sbi->max_proto);
+
+	if (sbi->type & AUTOFS_TYPE_OFFSET)
+		seq_printf(m, ",offset");
+	else if (sbi->type & AUTOFS_TYPE_DIRECT)
+		seq_printf(m, ",direct");
+	else
+		seq_printf(m, ",indirect");
+
+	return 0;
+}
+
 static struct super_operations autofs4_sops = {
 	.put_super	= autofs4_put_super,
 	.statfs		= simple_statfs,
+	.show_options	= autofs4_show_options,
 };
 
-enum {Opt_err, Opt_fd, Opt_uid, Opt_gid, Opt_pgrp, Opt_minproto, Opt_maxproto};
+enum {Opt_err, Opt_fd, Opt_uid, Opt_gid, Opt_pgrp, Opt_minproto, Opt_maxproto,
+	Opt_indirect, Opt_direct, Opt_offset};
 
 static match_table_t tokens = {
 	{Opt_fd, "fd=%u"},
@@ -104,11 +205,15 @@ static match_table_t tokens = {
 	{Opt_pgrp, "pgrp=%u"},
 	{Opt_minproto, "minproto=%u"},
 	{Opt_maxproto, "maxproto=%u"},
+	{Opt_indirect, "indirect"},
+	{Opt_direct, "direct"},
+	{Opt_offset, "offset"},
 	{Opt_err, NULL}
 };
 
 static int parse_options(char *options, int *pipefd, uid_t *uid, gid_t *gid,
-			 pid_t *pgrp, int *minproto, int *maxproto)
+			 pid_t *pgrp, unsigned int *type,
+			 int *minproto, int *maxproto)
 {
 	char *p;
 	substring_t args[MAX_OPT_ARGS];
@@ -162,6 +267,15 @@ static int parse_options(char *options, 
 				return 1;
 			*maxproto = option;
 			break;
+		case Opt_indirect:
+			*type = AUTOFS_TYPE_INDIRECT;
+			break;
+		case Opt_direct:
+			*type = AUTOFS_TYPE_DIRECT;
+			break;
+		case Opt_offset:
+			*type = AUTOFS_TYPE_DIRECT | AUTOFS_TYPE_OFFSET;
+			break;
 		default:
 			return 1;
 		}
@@ -180,6 +294,10 @@ static struct autofs_info *autofs4_mkroo
 	return ino;
 }
 
+static struct dentry_operations autofs4_sb_dentry_operations = {
+	.d_release      = autofs4_dentry_release,
+};
+
 int autofs4_fill_super(struct super_block *s, void *data, int silent)
 {
 	struct inode * root_inode;
@@ -188,7 +306,6 @@ int autofs4_fill_super(struct super_bloc
 	int pipefd;
 	struct autofs_sb_info *sbi;
 	struct autofs_info *ino;
-	int minproto, maxproto;
 
 	sbi = (struct autofs_sb_info *) kmalloc(sizeof(*sbi), GFP_KERNEL);
 	if ( !sbi )
@@ -199,13 +316,19 @@ int autofs4_fill_super(struct super_bloc
 
 	s->s_fs_info = sbi;
 	sbi->magic = AUTOFS_SBI_MAGIC;
+	sbi->root = NULL;
+	sbi->pipefd = -1;
 	sbi->catatonic = 0;
 	sbi->exp_timeout = 0;
 	sbi->oz_pgrp = process_group(current);
 	sbi->sb = s;
 	sbi->version = 0;
 	sbi->sub_version = 0;
+	sbi->type = 0;
+	sbi->min_proto = 0;
+	sbi->max_proto = 0;
 	init_MUTEX(&sbi->wq_sem);
+	spin_lock_init(&sbi->fs_lock);
 	sbi->queues = NULL;
 	s->s_blocksize = 1024;
 	s->s_blocksize_bits = 10;
@@ -219,38 +342,46 @@ int autofs4_fill_super(struct super_bloc
 	if (!ino)
 		goto fail_free;
 	root_inode = autofs4_get_inode(s, ino);
-	kfree(ino);
 	if (!root_inode)
-		goto fail_free;
+		goto fail_ino;
 
-	root_inode->i_op = &autofs4_root_inode_operations;
-	root_inode->i_fop = &autofs4_root_operations;
 	root = d_alloc_root(root_inode);
-	pipe = NULL;
-
 	if (!root)
 		goto fail_iput;
+	pipe = NULL;
+
+	root->d_op = &autofs4_sb_dentry_operations;
+	root->d_fsdata = ino;
 
 	/* Can this call block? */
 	if (parse_options(data, &pipefd,
 			  &root_inode->i_uid, &root_inode->i_gid,
-			  &sbi->oz_pgrp,
-			  &minproto, &maxproto)) {
+			  &sbi->oz_pgrp, &sbi->type,
+			  &sbi->min_proto, &sbi->max_proto)) {
 		printk("autofs: called with bogus options\n");
 		goto fail_dput;
 	}
 
+	root_inode->i_fop = &autofs4_root_operations;
+	root_inode->i_op = sbi->type & AUTOFS_TYPE_DIRECT ?
+			&autofs4_direct_root_inode_operations :
+			&autofs4_indirect_root_inode_operations;
+
 	/* Couldn't this be tested earlier? */
-	if (maxproto < AUTOFS_MIN_PROTO_VERSION ||
-	    minproto > AUTOFS_MAX_PROTO_VERSION) {
+	if (sbi->max_proto < AUTOFS_MIN_PROTO_VERSION ||
+	    sbi->min_proto > AUTOFS_MAX_PROTO_VERSION) {
 		printk("autofs: kernel does not match daemon version "
 		       "daemon (%d, %d) kernel (%d, %d)\n",
-			minproto, maxproto,
+			sbi->min_proto, sbi->max_proto,
 			AUTOFS_MIN_PROTO_VERSION, AUTOFS_MAX_PROTO_VERSION);
 		goto fail_dput;
 	}
 
-	sbi->version = maxproto > AUTOFS_MAX_PROTO_VERSION ? AUTOFS_MAX_PROTO_VERSION : maxproto;
+	/* Establish highest kernel protocol version */
+	if (sbi->max_proto > AUTOFS_MAX_PROTO_VERSION)
+		sbi->version = AUTOFS_MAX_PROTO_VERSION;
+	else
+		sbi->version = sbi->max_proto;
 	sbi->sub_version = AUTOFS_PROTO_SUBVERSION;
 
 	DPRINTK("pipe fd = %d, pgrp = %u", pipefd, sbi->oz_pgrp);
@@ -263,6 +394,14 @@ int autofs4_fill_super(struct super_bloc
 	if ( !pipe->f_op || !pipe->f_op->write )
 		goto fail_fput;
 	sbi->pipe = pipe;
+	sbi->pipefd = pipefd;
+
+	/*
+	 * Take a reference to the root dentry so we get a chance to
+	 * clean up the dentry tree on umount.
+	 * See autofs4_force_release.
+	 */
+	sbi->root = dget(root);
 
 	/*
 	 * Success! Install the root dentry now to indicate completion.
@@ -283,6 +422,8 @@ fail_dput:
 fail_iput:
 	printk("autofs: get root dentry failed\n");
 	iput(root_inode);
+fail_ino:
+	kfree(ino);
 fail_free:
 	kfree(sbi);
 fail_unlock:
diff -Nurp linux-2.6.9.orig/fs/autofs4/root.c linux-2.6.9/fs/autofs4/root.c
--- linux-2.6.9.orig/fs/autofs4/root.c	2004-10-19 05:53:06.000000000 +0800
+++ linux-2.6.9/fs/autofs4/root.c	2006-08-31 12:14:14.000000000 +0800
@@ -4,7 +4,7 @@
  *
  *  Copyright 1997-1998 Transmeta Corporation -- All Rights Reserved
  *  Copyright 1999-2000 Jeremy Fitzhardinge <jeremy@goop.org>
- *  Copyright 2001-2003 Ian Kent <raven@themaw.net>
+ *  Copyright 2001-2006 Ian Kent <raven@themaw.net>
  *
  * This file is part of the Linux kernel and is made available under
  * the terms of the GNU General Public License, version 2, or at your
@@ -19,7 +19,6 @@
 #include <linux/smp_lock.h>
 #include "autofs_i.h"
 
-static struct dentry *autofs4_dir_lookup(struct inode *,struct dentry *, struct nameidata *);
 static int autofs4_dir_symlink(struct inode *,struct dentry *,const char *);
 static int autofs4_dir_unlink(struct inode *,struct dentry *);
 static int autofs4_dir_rmdir(struct inode *,struct dentry *);
@@ -29,8 +28,8 @@ static int autofs4_dir_open(struct inode
 static int autofs4_dir_close(struct inode *inode, struct file *file);
 static int autofs4_dir_readdir(struct file * filp, void * dirent, filldir_t filldir);
 static int autofs4_root_readdir(struct file * filp, void * dirent, filldir_t filldir);
-static struct dentry *autofs4_root_lookup(struct inode *,struct dentry *, struct nameidata *);
-static int autofs4_dcache_readdir(struct file *, void *, filldir_t);
+static struct dentry *autofs4_lookup(struct inode *,struct dentry *, struct nameidata *);
+static int autofs4_follow_link(struct dentry *, struct nameidata *);
 
 struct file_operations autofs4_root_operations = {
 	.open		= dcache_dir_open,
@@ -47,16 +46,24 @@ struct file_operations autofs4_dir_opera
 	.readdir	= autofs4_dir_readdir,
 };
 
-struct inode_operations autofs4_root_inode_operations = {
-	.lookup		= autofs4_root_lookup,
+struct inode_operations autofs4_indirect_root_inode_operations = {
+	.lookup		= autofs4_lookup,
 	.unlink		= autofs4_dir_unlink,
 	.symlink	= autofs4_dir_symlink,
 	.mkdir		= autofs4_dir_mkdir,
 	.rmdir		= autofs4_dir_rmdir,
 };
 
+struct inode_operations autofs4_direct_root_inode_operations = {
+	.lookup		= autofs4_lookup,
+	.unlink		= autofs4_dir_unlink,
+	.mkdir		= autofs4_dir_mkdir,
+	.rmdir		= autofs4_dir_rmdir,
+	.follow_link	= autofs4_follow_link,
+};
+
 struct inode_operations autofs4_dir_inode_operations = {
-	.lookup		= autofs4_dir_lookup,
+	.lookup		= autofs4_lookup,
 	.unlink		= autofs4_dir_unlink,
 	.symlink	= autofs4_dir_symlink,
 	.mkdir		= autofs4_dir_mkdir,
@@ -82,86 +89,7 @@ static int autofs4_root_readdir(struct f
 
 	DPRINTK("needs_reghost = %d", sbi->needs_reghost);
 
-	return autofs4_dcache_readdir(file, dirent, filldir);
-}
-
-/* Update usage from here to top of tree, so that scan of
-   top-level directories will give a useful result */
-static void autofs4_update_usage(struct dentry *dentry)
-{
-	struct dentry *top = dentry->d_sb->s_root;
-
-	spin_lock(&dcache_lock);
-	for(; dentry != top; dentry = dentry->d_parent) {
-		struct autofs_info *ino = autofs4_dentry_ino(dentry);
-
-		if (ino) {
-			update_atime(dentry->d_inode);
-			ino->last_used = jiffies;
-		}
-	}
-	spin_unlock(&dcache_lock);
-}
-
-/*
- * From 2.4 kernel readdir.c
- */
-static int autofs4_dcache_readdir(struct file * filp, void * dirent, filldir_t filldir)
-{
-	int i;
-	struct dentry *dentry = filp->f_dentry;
-
-	i = filp->f_pos;
-	switch (i) {
-		case 0:
-			if (filldir(dirent, ".", 1, i, dentry->d_inode->i_ino, DT_DIR) < 0)
-				break;
-			i++;
-			filp->f_pos++;
-			/* fallthrough */
-		case 1:
-			if (filldir(dirent, "..", 2, i, dentry->d_parent->d_inode->i_ino, DT_DIR) < 0)
-				break;
-			i++;
-			filp->f_pos++;
-			/* fallthrough */
-		default: {
-			struct list_head *list;
-			int j = i-2;
-
-			spin_lock(&dcache_lock);
-			list = dentry->d_subdirs.next;
-
-			for (;;) {
-				if (list == &dentry->d_subdirs) {
-					spin_unlock(&dcache_lock);
-					return 0;
-				}
-				if (!j)
-					break;
-				j--;
-				list = list->next;
-			}
-
-			while(1) {
-				struct dentry *de = list_entry(list, struct dentry, d_child);
-
-				if (!d_unhashed(de) && de->d_inode) {
-					spin_unlock(&dcache_lock);
-					if (filldir(dirent, de->d_name.name, de->d_name.len, filp->f_pos, de->d_inode->i_ino, DT_UNKNOWN) < 0)
-						break;
-					spin_lock(&dcache_lock);
-				}
-				filp->f_pos++;
-				list = list->next;
-				if (list != &dentry->d_subdirs)
-					continue;
-				spin_unlock(&dcache_lock);
-				break;
-			}
-		}
-	}
-	return 0;
+	return dcache_readdir(file, dirent, filldir);
 }
 
 static int autofs4_dir_open(struct inode *inode, struct file *file)
@@ -169,8 +97,16 @@ static int autofs4_dir_open(struct inode
 	struct dentry *dentry = file->f_dentry;
 	struct vfsmount *mnt = file->f_vfsmnt;
 	struct autofs_sb_info *sbi = autofs4_sbi(dentry->d_sb);
+	struct dentry *cursor;
 	int status;
 
+	status = dcache_dir_open(inode, file);
+	if (status)
+		goto out;
+
+	cursor = file->private_data;
+	cursor->d_fsdata = NULL;
+
 	DPRINTK("file=%p dentry=%p %.*s",
 		file, dentry, dentry->d_name.len, dentry->d_name.name);
 
@@ -179,12 +115,15 @@ static int autofs4_dir_open(struct inode
 
 	if (autofs4_ispending(dentry)) {
 		DPRINTK("dentry busy");
-		return -EBUSY;
+		dcache_dir_close(inode, file);
+		status = -EBUSY;
+		goto out;
 	}
 
+	status = -ENOENT;
 	if (!d_mountpoint(dentry) && dentry->d_op && dentry->d_op->d_revalidate) {
 		struct nameidata nd;
-		int empty;
+		int empty, ret;
 
 		/* In case there are stale directory dentrys from a failed mount */
 		spin_lock(&dcache_lock);
@@ -195,10 +134,14 @@ static int autofs4_dir_open(struct inode
 			d_invalidate(dentry);
 
 		nd.flags = LOOKUP_DIRECTORY;
-		status = (dentry->d_op->d_revalidate)(dentry, &nd);
+		ret = (dentry->d_op->d_revalidate)(dentry, &nd);
 
-		if (!status)
-			return -ENOENT;
+		if (ret <= 0) {
+			if (ret < 0)
+				status = ret;
+			dcache_dir_close(inode, file);
+			goto out;
+		}
 	}
 
 	if (d_mountpoint(dentry)) {
@@ -206,24 +149,32 @@ static int autofs4_dir_open(struct inode
 		struct vfsmount *fp_mnt = mntget(mnt);
 		struct dentry *fp_dentry = dget(dentry);
 
-		while (follow_down(&fp_mnt, &fp_dentry) && d_mountpoint(fp_dentry));
+		if (!autofs4_follow_mount(&fp_mnt, &fp_dentry)) {
+			dput(fp_dentry);
+			mntput(fp_mnt);
+			dcache_dir_close(inode, file);
+			goto out;
+		}
 
 		fp = dentry_open(fp_dentry, fp_mnt, file->f_flags);
 		status = PTR_ERR(fp);
 		if (IS_ERR(fp)) {
-			file->private_data = NULL;
-			return status;
+			dcache_dir_close(inode, file);
+			goto out;
 		}
-		file->private_data = fp;
+		cursor->d_fsdata = fp;
 	}
-out:
 	return 0;
+out:
+	return status;
 }
 
 static int autofs4_dir_close(struct inode *inode, struct file *file)
 {
 	struct dentry *dentry = file->f_dentry;
 	struct autofs_sb_info *sbi = autofs4_sbi(dentry->d_sb);
+	struct dentry *cursor = file->private_data;
+	int status = 0;
 
 	DPRINTK("file=%p dentry=%p %.*s",
 		file, dentry, dentry->d_name.len, dentry->d_name.name);
@@ -233,26 +184,28 @@ static int autofs4_dir_close(struct inod
 
 	if (autofs4_ispending(dentry)) {
 		DPRINTK("dentry busy");
-		return -EBUSY;
+		status = -EBUSY;
+		goto out;
 	}
 
 	if (d_mountpoint(dentry)) {
-		struct file *fp = file->private_data;
-
-		if (!fp)
-			return -ENOENT;
-
+		struct file *fp = cursor->d_fsdata;
+		if (!fp) {
+			status = -ENOENT;
+			goto out;
+		}
 		filp_close(fp, current->files);
-		file->private_data = NULL;
 	}
 out:
-	return 0;
+	dcache_dir_close(inode, file);
+	return status;
 }
 
 static int autofs4_dir_readdir(struct file *file, void *dirent, filldir_t filldir)
 {
 	struct dentry *dentry = file->f_dentry;
 	struct autofs_sb_info *sbi = autofs4_sbi(dentry->d_sb);
+	struct dentry *cursor = file->private_data;
 	int status;
 
 	DPRINTK("file=%p dentry=%p %.*s",
@@ -267,7 +220,7 @@ static int autofs4_dir_readdir(struct fi
 	}
 
 	if (d_mountpoint(dentry)) {
-		struct file *fp = file->private_data;
+		struct file *fp = cursor->d_fsdata;
 
 		if (!fp)
 			return -ENOENT;
@@ -282,28 +235,34 @@ static int autofs4_dir_readdir(struct fi
 		return status;
 	}
 out:
-	return autofs4_dcache_readdir(file, dirent, filldir);
+	return dcache_readdir(file, dirent, filldir);
 }
 
-static int try_to_fill_dentry(struct dentry *dentry, 
-			      struct super_block *sb,
-			      struct autofs_sb_info *sbi, int flags)
+static int try_to_fill_dentry(struct dentry *dentry, int flags)
 {
-	struct autofs_info *de_info = autofs4_dentry_ino(dentry);
+	struct autofs_sb_info *sbi = autofs4_sbi(dentry->d_sb);
+	struct autofs_info *ino = autofs4_dentry_ino(dentry);
 	int status = 0;
 
 	/* Block on any pending expiry here; invalidate the dentry
            when expiration is done to trigger mount request with a new
            dentry */
-	if (de_info && (de_info->flags & AUTOFS_INF_EXPIRING)) {
+	if (ino && (ino->flags & AUTOFS_INF_EXPIRING)) {
 		DPRINTK("waiting for expire %p name=%.*s",
 			 dentry, dentry->d_name.len, dentry->d_name.name);
 
 		status = autofs4_wait(sbi, dentry, NFY_NONE);
-		
+
 		DPRINTK("expire done status=%d", status);
-		
-		return 0;
+
+		/*
+		 * If the directory still exists the mount request must
+		 * continue otherwise it can't be followed at the right
+		 * time during the walk.
+		 */
+		status = d_invalidate(dentry);
+		if (status != -EBUSY)
+			return -ENOENT;
 	}
 
 	DPRINTK("dentry=%p %.*s ino=%p",
@@ -318,19 +277,15 @@ static int try_to_fill_dentry(struct den
 		 
 		DPRINTK("mount done status=%d", status);
 
-		if (status && dentry->d_inode)
-			return 0; /* Try to get the kernel to invalidate this dentry */
-		
 		/* Turn this into a real negative dentry? */
 		if (status == -ENOENT) {
-			dentry->d_time = jiffies + AUTOFS_NEGATIVE_TIMEOUT;
 			spin_lock(&dentry->d_lock);
 			dentry->d_flags &= ~DCACHE_AUTOFS_PENDING;
 			spin_unlock(&dentry->d_lock);
-			return 1;
+			return status;
 		} else if (status) {
 			/* Return a negative dentry, but leave it "pending" */
-			return 1;
+			return status;
 		}
 	/* Trigger mount for path component or follow link */
 	} else if (flags & (LOOKUP_CONTINUE | LOOKUP_DIRECTORY) ||
@@ -349,19 +304,83 @@ static int try_to_fill_dentry(struct den
 			spin_lock(&dentry->d_lock);
 			dentry->d_flags &= ~DCACHE_AUTOFS_PENDING;
 			spin_unlock(&dentry->d_lock);
-			return 0;
+			return status;
 		}
 	}
 
-	/* We don't update the usages for the autofs daemon itself, this
-	   is necessary for recursive autofs mounts */
-	if (!autofs4_oz_mode(sbi))
-		autofs4_update_usage(dentry);
+	/* Initialize expiry counter after successful mount */
+	if (ino)
+		ino->last_used = jiffies;
 
 	spin_lock(&dentry->d_lock);
 	dentry->d_flags &= ~DCACHE_AUTOFS_PENDING;
 	spin_unlock(&dentry->d_lock);
-	return 1;
+	return status;
+}
+
+/* For autofs direct mounts the follow link triggers the mount */
+static int autofs4_follow_link(struct dentry *dentry, struct nameidata *nd)
+{
+	struct autofs_sb_info *sbi = autofs4_sbi(dentry->d_sb);
+	struct autofs_info *ino = autofs4_dentry_ino(dentry);
+	int oz_mode = autofs4_oz_mode(sbi);
+	unsigned int lookup_type;
+	int status;
+
+	DPRINTK("dentry=%p %.*s oz_mode=%d nd->flags=%d",
+		dentry, dentry->d_name.len, dentry->d_name.name, oz_mode,
+		nd->flags);
+
+	/* If it's our master or we shouldn't trigger a mount we're done */
+	lookup_type = nd->flags & (LOOKUP_CONTINUE | LOOKUP_DIRECTORY);
+	if (oz_mode || !lookup_type)
+		goto done;
+
+	/* If an expire request is pending wait for it. */
+	if (ino && (ino->flags & AUTOFS_INF_EXPIRING)) {
+		DPRINTK("waiting for active request %p name=%.*s",
+			dentry, dentry->d_name.len, dentry->d_name.name);
+
+		status = autofs4_wait(sbi, dentry, NFY_NONE);
+
+		DPRINTK("request done status=%d", status);
+	}
+
+	/*
+	 * If the dentry contains directories then it is an
+	 * autofs multi-mount with no root mount offset. So
+	 * don't try to mount it again.
+	 */
+	spin_lock(&dcache_lock);
+	if (!d_mountpoint(dentry) && __simple_empty(dentry)) {
+		spin_unlock(&dcache_lock);
+
+		status = try_to_fill_dentry(dentry, 0);
+		if (status)
+			goto out_error;
+
+		/*
+		 * The mount succeeded but if there is no root mount
+		 * it must be an autofs multi-mount with no root offset
+		 * so we don't need to follow the mount.
+		 */
+		if (d_mountpoint(dentry)) {
+			if (!autofs4_follow_mount(&nd->mnt, &nd->dentry)) {
+				status = -ENOENT;
+				goto out_error;
+			}
+		}
+
+		goto done;
+	}
+	spin_unlock(&dcache_lock);
+
+done:
+	return NULL;
+
+out_error:
+	path_release(nd);
+	return ERR_PTR(status);
 }
 
 /*
@@ -370,47 +389,63 @@ static int try_to_fill_dentry(struct den
  * yet completely filled in, and revalidate has to delay such
  * lookups..
  */
-static int autofs4_revalidate(struct dentry * dentry, struct nameidata *nd)
+static int autofs4_revalidate(struct dentry *dentry, struct nameidata *nd)
 {
-	struct inode * dir = dentry->d_parent->d_inode;
+	struct inode *dir = dentry->d_parent->d_inode;
 	struct autofs_sb_info *sbi = autofs4_sbi(dir->i_sb);
 	int oz_mode = autofs4_oz_mode(sbi);
 	int flags = nd ? nd->flags : 0;
-	int status = 1;
+	int status;
 
 	/* Pending dentry */
 	if (autofs4_ispending(dentry)) {
-		if (!oz_mode)
-			status = try_to_fill_dentry(dentry, dir->i_sb, sbi, flags);
+		/* The daemon never causes a mount to trigger */
+		if (oz_mode)
+			return 1;
+
+		/*
+		 * A zero status is success otherwise we have a
+		 * negative error code.
+		 */
+		status = try_to_fill_dentry(dentry, flags);
+		if (status == 0)
+			return 1;
+
 		return status;
 	}
 
 	/* Negative dentry.. invalidate if "old" */
 	if (dentry->d_inode == NULL)
-		return (dentry->d_time - jiffies <= AUTOFS_NEGATIVE_TIMEOUT);
+		return 0;
 
 	/* Check for a non-mountpoint directory with no contents */
 	spin_lock(&dcache_lock);
 	if (S_ISDIR(dentry->d_inode->i_mode) &&
 	    !d_mountpoint(dentry) && 
-	    list_empty(&dentry->d_subdirs)) {
+	    __simple_empty(dentry)) {
 		DPRINTK("dentry=%p %.*s, emptydir",
 			 dentry, dentry->d_name.len, dentry->d_name.name);
 		spin_unlock(&dcache_lock);
-		if (!oz_mode)
-			status = try_to_fill_dentry(dentry, dir->i_sb, sbi, flags);
+		/* The daemon never causes a mount to trigger */
+		if (oz_mode)
+			return 1;
+
+		/*
+		 * A zero status is success otherwise we have a
+		 * negative error code.
+		 */
+		status = try_to_fill_dentry(dentry, flags);
+		if (status == 0)
+			return 1;
+
 		return status;
 	}
 	spin_unlock(&dcache_lock);
 
-	/* Update the usage list */
-	if (!oz_mode)
-		autofs4_update_usage(dentry);
-
 	return 1;
 }
 
-static void autofs4_dentry_release(struct dentry *de)
+void autofs4_dentry_release(struct dentry *de)
 {
 	struct autofs_info *inf;
 
@@ -439,23 +474,8 @@ static struct dentry_operations autofs4_
 	.d_release	= autofs4_dentry_release,
 };
 
-/* Lookups in non-root dirs never find anything - if it's there, it's
-   already in the dcache */
-static struct dentry *autofs4_dir_lookup(struct inode *dir, struct dentry *dentry, struct nameidata *nd)
-{
-#if 0
-	DPRINTK("ignoring lookup of %.*s/%.*s",
-		 dentry->d_parent->d_name.len, dentry->d_parent->d_name.name,
-		 dentry->d_name.len, dentry->d_name.name);
-#endif
-
-	dentry->d_fsdata = NULL;
-	d_add(dentry, NULL);
-	return NULL;
-}
-
 /* Lookups in the root directory */
-static struct dentry *autofs4_root_lookup(struct inode *dir, struct dentry *dentry, struct nameidata *nd)
+static struct dentry *autofs4_lookup(struct inode *dir, struct dentry *dentry, struct nameidata *nd)
 {
 	struct autofs_sb_info *sbi;
 	int oz_mode;
@@ -463,12 +483,13 @@ static struct dentry *autofs4_root_looku
 	DPRINTK("name = %.*s",
 		dentry->d_name.len, dentry->d_name.name);
 
+	/* File name too long to exist */
 	if (dentry->d_name.len > NAME_MAX)
-		return ERR_PTR(-ENAMETOOLONG);/* File name too long to exist */
+		return ERR_PTR(-ENAMETOOLONG);
 
 	sbi = autofs4_sbi(dir->i_sb);
-
 	oz_mode = autofs4_oz_mode(sbi);
+
 	DPRINTK("pid = %u, pgrp = %u, catatonic = %d, oz_mode = %d",
 		 current->pid, process_group(current), sbi->catatonic, oz_mode);
 
@@ -512,6 +533,9 @@ static struct dentry *autofs4_root_looku
 			    return ERR_PTR(-ERESTARTNOINTR);
 			}
 		}
+		spin_lock(&dentry->d_lock);
+		dentry->d_flags &= ~DCACHE_AUTOFS_PENDING;
+		spin_unlock(&dentry->d_lock);
 	}
 
 	/*
@@ -520,7 +544,7 @@ static struct dentry *autofs4_root_looku
 	 * doesn't do the right thing for all system calls, but it should
 	 * be OK for the operations we permit from an autofs.
 	 */
-	if ( dentry->d_inode && d_unhashed(dentry) )
+	if (dentry->d_inode && d_unhashed(dentry))
 		return ERR_PTR(-ENOENT);
 
 	return NULL;
@@ -532,6 +556,7 @@ static int autofs4_dir_symlink(struct in
 {
 	struct autofs_sb_info *sbi = autofs4_sbi(dir->i_sb);
 	struct autofs_info *ino = autofs4_dentry_ino(dentry);
+	struct autofs_info *p_ino;
 	struct inode *inode;
 	char *cp;
 
@@ -565,6 +590,10 @@ static int autofs4_dir_symlink(struct in
 
 	dentry->d_fsdata = ino;
 	ino->dentry = dget(dentry);
+	atomic_inc(&ino->count);
+	p_ino = autofs4_dentry_ino(dentry->d_parent);
+	if (p_ino && dentry->d_parent != dentry)
+		atomic_inc(&p_ino->count);
 	ino->inode = inode;
 
 	dir->i_mtime = CURRENT_TIME;
@@ -591,11 +620,17 @@ static int autofs4_dir_unlink(struct ino
 {
 	struct autofs_sb_info *sbi = autofs4_sbi(dir->i_sb);
 	struct autofs_info *ino = autofs4_dentry_ino(dentry);
+	struct autofs_info *p_ino;
 	
 	/* This allows root to remove symlinks */
 	if ( !autofs4_oz_mode(sbi) && !capable(CAP_SYS_ADMIN) )
 		return -EACCES;
 
+	if (atomic_dec_and_test(&ino->count)) {
+		p_ino = autofs4_dentry_ino(dentry->d_parent);
+		if (p_ino && dentry->d_parent != dentry)
+			atomic_dec(&p_ino->count);
+	}
 	dput(ino->dentry);
 
 	dentry->d_inode->i_size = 0;
@@ -612,6 +647,7 @@ static int autofs4_dir_rmdir(struct inod
 {
 	struct autofs_sb_info *sbi = autofs4_sbi(dir->i_sb);
 	struct autofs_info *ino = autofs4_dentry_ino(dentry);
+	struct autofs_info *p_ino;
 	
 	if (!autofs4_oz_mode(sbi))
 		return -EACCES;
@@ -624,8 +660,12 @@ static int autofs4_dir_rmdir(struct inod
 	__d_drop(dentry);
 	spin_unlock(&dcache_lock);
 
+	if (atomic_dec_and_test(&ino->count)) {
+		p_ino = autofs4_dentry_ino(dentry->d_parent);
+		if (p_ino && dentry->d_parent != dentry)
+			atomic_dec(&p_ino->count);
+	}
 	dput(ino->dentry);
-
 	dentry->d_inode->i_size = 0;
 	dentry->d_inode->i_nlink = 0;
 
@@ -639,6 +679,7 @@ static int autofs4_dir_mkdir(struct inod
 {
 	struct autofs_sb_info *sbi = autofs4_sbi(dir->i_sb);
 	struct autofs_info *ino = autofs4_dentry_ino(dentry);
+	struct autofs_info *p_ino;
 	struct inode *inode;
 
 	if ( !autofs4_oz_mode(sbi) )
@@ -661,6 +702,10 @@ static int autofs4_dir_mkdir(struct inod
 
 	dentry->d_fsdata = ino;
 	ino->dentry = dget(dentry);
+	atomic_inc(&ino->count);
+	p_ino = autofs4_dentry_ino(dentry->d_parent);
+	if (p_ino && dentry->d_parent != dentry)
+		atomic_inc(&p_ino->count);
 	ino->inode = inode;
 	dir->i_nlink++;
 	dir->i_mtime = CURRENT_TIME;
@@ -744,7 +789,7 @@ static inline int autofs4_ask_umount(str
 {
 	int status = 0;
 
-	if (may_umount(mnt) == 0)
+	if (may_umount(mnt))
 		status = 1;
 
 	DPRINTK("returning %d", status);
diff -Nurp linux-2.6.9.orig/fs/autofs4/waitq.c linux-2.6.9/fs/autofs4/waitq.c
--- linux-2.6.9.orig/fs/autofs4/waitq.c	2004-10-19 05:55:27.000000000 +0800
+++ linux-2.6.9/fs/autofs4/waitq.c	2006-08-31 12:14:13.000000000 +0800
@@ -3,7 +3,7 @@
  * linux/fs/autofs/waitq.c
  *
  *  Copyright 1997-1998 Transmeta Corporation -- All Rights Reserved
- *  Copyright 2001-2003 Ian Kent <raven@themaw.net>
+ *  Copyright 2001-2006 Ian Kent <raven@themaw.net>
  *
  * This file is part of the Linux kernel and is made available under
  * the terms of the GNU General Public License, version 2, or at your
@@ -33,7 +33,7 @@ void autofs4_catatonic_mode(struct autof
 	sbi->catatonic = 1;
 	wq = sbi->queues;
 	sbi->queues = NULL;	/* Erase all wait queues */
-	while ( wq ) {
+	while (wq) {
 		nwq = wq->next;
 		wq->status = -ENOENT; /* Magic is gone - report failure */
 		kfree(wq->name);
@@ -45,7 +45,6 @@ void autofs4_catatonic_mode(struct autof
 		fput(sbi->pipe);	/* Close the pipe */
 		sbi->pipe = NULL;
 	}
-
 	shrink_dcache_sb(sbi->sb);
 }
 
@@ -98,7 +97,10 @@ static void autofs4_notify_daemon(struct
 
 	pkt.hdr.proto_version = sbi->version;
 	pkt.hdr.type = type;
-	if (type == autofs_ptype_missing) {
+	switch (type) {
+	/* Kernel protocol v4 missing and expire packets */
+	case autofs_ptype_missing:
+	{
 		struct autofs_packet_missing *mp = &pkt.missing;
 
 		pktsz = sizeof(*mp);
@@ -107,7 +109,10 @@ static void autofs4_notify_daemon(struct
 		mp->len = wq->len;
 		memcpy(mp->name, wq->name, wq->len);
 		mp->name[wq->len] = '\0';
-	} else if (type == autofs_ptype_expire_multi) {
+		break;
+	}
+	case autofs_ptype_expire_multi:
+	{
 		struct autofs_packet_expire_multi *ep = &pkt.expire_multi;
 
 		pktsz = sizeof(*ep);
@@ -116,7 +121,34 @@ static void autofs4_notify_daemon(struct
 		ep->len = wq->len;
 		memcpy(ep->name, wq->name, wq->len);
 		ep->name[wq->len] = '\0';
-	} else {
+		break;
+	}
+	/*
+	 * Kernel protocol v5 packet for handling indirect and direct
+	 * mount missing and expire requests
+	 */
+	case autofs_ptype_missing_indirect:
+	case autofs_ptype_expire_indirect:
+	case autofs_ptype_missing_direct:
+	case autofs_ptype_expire_direct:
+	{
+		struct autofs_v5_packet *packet = &pkt.v5_packet;
+
+		pktsz = sizeof(*packet);
+
+		packet->wait_queue_token = wq->wait_queue_token;
+		packet->len = wq->len;
+		memcpy(packet->name, wq->name, wq->len);
+		packet->name[wq->len] = '\0';
+		packet->dev = wq->dev;
+		packet->ino = wq->ino;
+		packet->uid = wq->uid;
+		packet->gid = wq->gid;
+		packet->pid = wq->pid;
+		packet->tgid = wq->tgid;
+		break;
+	}
+	default:
 		printk("autofs4_notify_daemon: bad type %d!\n", type);
 		return;
 	}
@@ -157,43 +189,95 @@ static int autofs4_getpath(struct autofs
 	return len;
 }
 
+static struct autofs_wait_queue *
+autofs4_find_wait(struct autofs_sb_info *sbi,
+		  char *name, unsigned int hash, unsigned int len)
+{
+	struct autofs_wait_queue *wq = NULL;
+
+	for (wq = sbi->queues ; wq ; wq = wq->next) {
+		if (wq->hash == hash &&
+		    wq->len == len &&
+		    wq->name && !memcmp(wq->name, name, len))
+			break;
+	}
+	return wq;
+}
+
 int autofs4_wait(struct autofs_sb_info *sbi, struct dentry *dentry,
 		enum autofs_notify notify)
 {
+	struct autofs_info *ino;
 	struct autofs_wait_queue *wq;
 	char *name;
-	int len, status;
+	unsigned int len = 0;
+	unsigned int hash = 0;
+	int status, type;
 
 	/* In catatonic mode, we don't wait for nobody */
-	if ( sbi->catatonic )
+	if (sbi->catatonic)
 		return -ENOENT;
 	
 	name = kmalloc(NAME_MAX + 1, GFP_KERNEL);
 	if (!name)
 		return -ENOMEM;
 
-	len = autofs4_getpath(sbi, dentry, &name);
-	if (!len) {
-		kfree(name);
-		return -ENOENT;
+	/* If this is a direct mount request create a dummy name */
+	if (IS_ROOT(dentry) && (sbi->type & AUTOFS_TYPE_DIRECT))
+		len = sprintf(name, "%p", dentry);
+	else {
+		len = autofs4_getpath(sbi, dentry, &name);
+		if (!len) {
+			kfree(name);
+			return -ENOENT;
+		}
 	}
+	hash = full_name_hash(name, len);
 
 	if (down_interruptible(&sbi->wq_sem)) {
 		kfree(name);
 		return -EINTR;
 	}
 
-	for (wq = sbi->queues ; wq ; wq = wq->next) {
-		if (wq->hash == dentry->d_name.hash &&
-		    wq->len == len &&
-		    wq->name && !memcmp(wq->name, name, len))
-			break;
+	wq = autofs4_find_wait(sbi, name, hash, len);
+	ino = autofs4_dentry_ino(dentry);
+	if (!wq && ino && notify == NFY_NONE) {
+		/*
+		 * Either we've betean the pending expire to post it's
+		 * wait or it finished while we waited on the mutex.
+		 * So we need to wait till either, the wait appears
+		 * or the expire finishes.
+		 */
+
+		while (ino->flags & AUTOFS_INF_EXPIRING) {
+			up(&sbi->wq_sem);
+			set_current_state(TASK_INTERRUPTIBLE);
+			schedule_timeout(HZ/10);
+			if (down_interruptible(&sbi->wq_sem)) {
+				kfree(name);
+				return -EINTR;
+			}
+			wq = autofs4_find_wait(sbi, name, hash, len);
+			if (wq)
+				break;
+		}
+
+		/*
+		 * Not ideal but the status has already gone. Of the two
+		 * cases where we wait on NFY_NONE neither depend on the
+		 * return status of the wait.
+		 */
+		if (!wq) {
+			kfree(name);
+			up(&sbi->wq_sem);
+			return 0;
+		}
 	}
 
-	if ( !wq ) {
+	if (!wq) {
 		/* Create a new wait queue */
 		wq = kmalloc(sizeof(struct autofs_wait_queue),GFP_KERNEL);
-		if ( !wq ) {
+		if (!wq) {
 			kfree(name);
 			up(&sbi->wq_sem);
 			return -ENOMEM;
@@ -205,25 +289,44 @@ int autofs4_wait(struct autofs_sb_info *
 		wq->next = sbi->queues;
 		sbi->queues = wq;
 		init_waitqueue_head(&wq->queue);
-		wq->hash = dentry->d_name.hash;
+		wq->hash = hash;
 		wq->name = name;
 		wq->len = len;
+		wq->dev = autofs4_get_dev(sbi);
+		wq->ino = autofs4_get_ino(sbi);
+		wq->uid = current->uid;
+		wq->gid = current->gid;
+		wq->pid = current->pid;
+		wq->tgid = current->tgid;
 		wq->status = -EINTR; /* Status return if interrupted */
 		atomic_set(&wq->wait_ctr, 2);
 		up(&sbi->wq_sem);
 
-		DPRINTK("new wait id = 0x%08lx, name = %.*s, nfy=%d",
+		if (sbi->version < 5) {
+			if (notify == NFY_MOUNT)
+				type = autofs_ptype_missing;
+			else
+				type = autofs_ptype_expire_multi;
+		} else {
+			if (notify == NFY_MOUNT)
+				type = (sbi->type & AUTOFS_TYPE_DIRECT) ?
+					autofs_ptype_missing_direct :
+					 autofs_ptype_missing_indirect;
+			else
+				type = (sbi->type & AUTOFS_TYPE_DIRECT) ?
+					autofs_ptype_expire_direct :
+					autofs_ptype_expire_indirect;
+		}
+
+		DPRINTK("new wait id = 0x%08lx, name = %.*s, nfy=%d\n",
 			(unsigned long) wq->wait_queue_token, wq->len, wq->name, notify);
+
 		/* autofs4_notify_daemon() may block */
-		if (notify != NFY_NONE) {
-			autofs4_notify_daemon(sbi,wq, 
-					notify == NFY_MOUNT ?
-						  autofs_ptype_missing :
-						  autofs_ptype_expire_multi);
-		}
+		autofs4_notify_daemon(sbi, wq, type);
 	} else {
 		atomic_inc(&wq->wait_ctr);
 		up(&sbi->wq_sem);
+		kfree(name);
 		DPRINTK("existing wait id = 0x%08lx, name = %.*s, nfy=%d",
 			(unsigned long) wq->wait_queue_token, wq->len, wq->name, notify);
 	}
@@ -275,12 +378,12 @@ int autofs4_wait_release(struct autofs_s
 	struct autofs_wait_queue *wq, **wql;
 
 	down(&sbi->wq_sem);
-	for ( wql = &sbi->queues ; (wq = *wql) != 0 ; wql = &wq->next ) {
-		if ( wq->wait_queue_token == wait_queue_token )
+	for (wql = &sbi->queues ; (wq = *wql) != 0 ; wql = &wq->next) {
+		if (wq->wait_queue_token == wait_queue_token)
 			break;
 	}
 
-	if ( !wq ) {
+	if (!wq) {
 		up(&sbi->wq_sem);
 		return -EINVAL;
 	}
diff -Nurp linux-2.6.9.orig/fs/namei.c linux-2.6.9/fs/namei.c
--- linux-2.6.9.orig/fs/namei.c	2004-10-19 05:53:46.000000000 +0800
+++ linux-2.6.9/fs/namei.c	2006-08-31 12:14:14.000000000 +0800
@@ -288,6 +288,29 @@ void path_release_on_umount(struct namei
 	_mntput(nd->mnt);
 }
 
+static inline struct dentry *do_revalidate(struct dentry *dentry, struct nameidata *nd)
+{
+	int status = dentry->d_op->d_revalidate(dentry, nd);
+	if (unlikely(status <= 0)) {
+		/*
+		 * The dentry failed validation.
+		 * If d_revalidate returned 0 attempt to invalidate
+		 * the dentry otherwise d_revalidate is asking us
+		 * to return a fail status.
+		 */
+		if (!status) {
+			if (!d_invalidate(dentry)) {
+				dput(dentry);
+				dentry = NULL;
+			}
+		} else {
+			dput(dentry);
+			dentry = ERR_PTR(status);
+		}
+	}
+	return dentry;
+}
+
 /*
  * Internal lookup() using the new generic dcache.
  * SMP-safe
@@ -302,12 +325,9 @@ static struct dentry * cached_lookup(str
 	if (!dentry)
 		dentry = d_lookup(parent, name);
 
-	if (dentry && dentry->d_op && dentry->d_op->d_revalidate) {
-		if (!dentry->d_op->d_revalidate(dentry, nd) && !d_invalidate(dentry)) {
-			dput(dentry);
-			dentry = NULL;
-		}
-	}
+	if (dentry && dentry->d_op && dentry->d_op->d_revalidate)
+		dentry = do_revalidate(dentry, nd);
+
 	return dentry;
 }
 
@@ -400,10 +420,9 @@ static struct dentry * real_lookup(struc
 	 */
 	up(&dir->i_sem);
 	if (result->d_op && result->d_op->d_revalidate) {
-		if (!result->d_op->d_revalidate(result, nd) && !d_invalidate(result)) {
-			dput(result);
+		result = do_revalidate(result, nd);
+		if (!result)
 			result = ERR_PTR(-ENOENT);
-		}
 	}
 	return result;
 }
@@ -635,12 +654,12 @@ need_lookup:
 	goto done;
 
 need_revalidate:
-	if (dentry->d_op->d_revalidate(dentry, nd))
-		goto done;
-	if (d_invalidate(dentry))
-		goto done;
-	dput(dentry);
-	goto need_lookup;
+	dentry = do_revalidate(dentry, nd);
+	if (!dentry)
+		goto need_lookup;
+	if (IS_ERR(dentry))
+		goto fail;
+	goto done;
 
 fail:
 	return PTR_ERR(dentry);
@@ -746,6 +765,11 @@ int fastcall link_path_walk(const char *
 
 		if (inode->i_op->follow_link) {
 			mntget(next.mnt);
+			if (next.mnt != nd->mnt) {
+				dput(nd->dentry);
+				nd->mnt = next.mnt;
+				nd->dentry = dget(next.dentry);
+			}
 			err = do_follow_link(next.dentry, nd);
 			dput(next.dentry);
 			mntput(next.mnt);
@@ -800,6 +824,11 @@ last_component:
 		if ((lookup_flags & LOOKUP_FOLLOW)
 		    && inode && inode->i_op && inode->i_op->follow_link) {
 			mntget(next.mnt);
+			if (next.mnt != nd->mnt) {
+				dput(nd->dentry);
+				nd->mnt = next.mnt;
+				nd->dentry = dget(next.dentry);
+			}
 			err = do_follow_link(next.dentry, nd);
 			dput(next.dentry);
 			mntput(next.mnt);
diff -Nurp linux-2.6.9.orig/fs/namespace.c linux-2.6.9/fs/namespace.c
--- linux-2.6.9.orig/fs/namespace.c	2004-10-19 05:54:37.000000000 +0800
+++ linux-2.6.9/fs/namespace.c	2006-08-31 12:14:13.000000000 +0800
@@ -309,9 +309,9 @@ resume:
 	spin_unlock(&vfsmount_lock);
 
 	if (actual_refs > minimum_refs)
-		return -EBUSY;
+		return 0;
 
-	return 0;
+	return 1;
 }
 
 EXPORT_SYMBOL(may_umount_tree);
@@ -331,9 +331,10 @@ EXPORT_SYMBOL(may_umount_tree);
  */
 int may_umount(struct vfsmount *mnt)
 {
+	int ret = 1;
 	if (atomic_read(&mnt->mnt_count) > 2)
-		return -EBUSY;
-	return 0;
+		ret = 0;
+	return ret;
 }
 
 EXPORT_SYMBOL(may_umount);
diff -Nurp linux-2.6.9.orig/include/linux/auto_fs4.h linux-2.6.9/include/linux/auto_fs4.h
--- linux-2.6.9.orig/include/linux/auto_fs4.h	2004-10-19 05:53:08.000000000 +0800
+++ linux-2.6.9/include/linux/auto_fs4.h	2006-08-31 12:14:13.000000000 +0800
@@ -19,18 +19,37 @@
 #undef AUTOFS_MIN_PROTO_VERSION
 #undef AUTOFS_MAX_PROTO_VERSION
 
-#define AUTOFS_PROTO_VERSION		4
+#define AUTOFS_PROTO_VERSION		5
 #define AUTOFS_MIN_PROTO_VERSION	3
-#define AUTOFS_MAX_PROTO_VERSION	4
+#define AUTOFS_MAX_PROTO_VERSION	5
 
-#define AUTOFS_PROTO_SUBVERSION         5
+#define AUTOFS_PROTO_SUBVERSION		0
 
 /* Mask for expire behaviour */
 #define AUTOFS_EXP_IMMEDIATE		1
 #define AUTOFS_EXP_LEAVES		2
 
-/* New message type */
-#define autofs_ptype_expire_multi	2	/* Expire entry (umount request) */
+/* Daemon notification packet types */
+enum autofs_notify {
+	NFY_NONE,
+	NFY_MOUNT,
+	NFY_EXPIRE
+};
+
+/* Kernel protocol version 4 packet types */
+
+/* Expire entry (umount request) */
+#define autofs_ptype_expire_multi	2
+
+/* Kernel protocol version 5 packet types */
+
+/* Indirect mount missing and expire requests. */
+#define autofs_ptype_missing_indirect	3
+#define autofs_ptype_expire_indirect	4
+
+/* Direct mount missing and expire requests */
+#define autofs_ptype_missing_direct	5
+#define autofs_ptype_expire_direct	6
 
 /* v4 multi expire (via pipe) */
 struct autofs_packet_expire_multi {
@@ -40,14 +59,36 @@ struct autofs_packet_expire_multi {
 	char name[NAME_MAX+1];
 };
 
+/* autofs v5 common packet struct */
+struct autofs_v5_packet {
+	struct autofs_packet_hdr hdr;
+	autofs_wqt_t wait_queue_token;
+	__u32 dev;
+	__u64 ino;
+	__u32 uid;
+	__u32 gid;
+	__u32 pid;
+	__u32 tgid;
+	__u32 len;
+	char name[NAME_MAX+1];
+};
+
+typedef struct autofs_v5_packet autofs_packet_missing_indirect_t;
+typedef struct autofs_v5_packet autofs_packet_expire_indirect_t;
+typedef struct autofs_v5_packet autofs_packet_missing_direct_t;
+typedef struct autofs_v5_packet autofs_packet_expire_direct_t;
+
 union autofs_packet_union {
 	struct autofs_packet_hdr hdr;
 	struct autofs_packet_missing missing;
 	struct autofs_packet_expire expire;
 	struct autofs_packet_expire_multi expire_multi;
+	struct autofs_v5_packet v5_packet;
 };
 
 #define AUTOFS_IOC_EXPIRE_MULTI		_IOW(0x93,0x66,int)
+#define AUTOFS_IOC_EXPIRE_INDIRECT	AUTOFS_IOC_EXPIRE_MULTI
+#define AUTOFS_IOC_EXPIRE_DIRECT	AUTOFS_IOC_EXPIRE_MULTI
 #define AUTOFS_IOC_PROTOSUBVER		_IOR(0x93,0x67,int)
 #define AUTOFS_IOC_ASKREGHOST           _IOR(0x93,0x68,int)
 #define AUTOFS_IOC_TOGGLEREGHOST        _IOR(0x93,0x69,int)