Merge branch 'linus' into x86/x2apic

Conflicts:

	drivers/pci/dmar.c

Signed-off-by: Ingo Molnar <mingo@elte.hu>

45 files changed, 1429 insertions, 937 deletions

diff --git a/fs/anon_inodes.c b/fs/anon_inodes.c
index 977ef208c05..3662dd44896 100644
--- a/fs/anon_inodes.c
+++ b/fs/anon_inodes.c
@@ -58,8 +58,9 @@ static struct dentry_operations anon_inodefs_dentry_operations = {
  *                    of the file
  *
  * @name:    [in]    name of the "class" of the new file
- * @fops     [in]    file operations for the new file
- * @priv     [in]    private data for the new file (will be file's private_data)
+ * @fops:    [in]    file operations for the new file
+ * @priv:    [in]    private data for the new file (will be file's private_data)
+ * @flags:   [in]    flags
  *
  * Creates a new file by hooking it on a single inode. This is useful for files
  * that do not need to have a full-fledged inode in order to operate correctly.
@@ -68,7 +69,7 @@ static struct dentry_operations anon_inodefs_dentry_operations = {
  * setup.  Returns new descriptor or -error.
  */
 int anon_inode_getfd(const char *name, const struct file_operations *fops,
-		     void *priv)
+		     void *priv, int flags)
 {
 	struct qstr this;
 	struct dentry *dentry;
@@ -78,7 +79,7 @@ int anon_inode_getfd(const char *name, const struct file_operations *fops,
 	if (IS_ERR(anon_inode_inode))
 		return -ENODEV;
 
-	error = get_unused_fd();
+	error = get_unused_fd_flags(flags);
 	if (error < 0)
 		return error;
 	fd = error;
@@ -115,7 +116,7 @@ int anon_inode_getfd(const char *name, const struct file_operations *fops,
 	file->f_mapping = anon_inode_inode->i_mapping;
 
 	file->f_pos = 0;
-	file->f_flags = O_RDWR;
+	file->f_flags = O_RDWR | (flags & O_NONBLOCK);
 	file->f_version = 0;
 	file->private_data = priv;
 
diff --git a/fs/autofs4/autofs_i.h b/fs/autofs4/autofs_i.h
index c3d352d7fa9..69a2f5c9231 100644
--- a/fs/autofs4/autofs_i.h
+++ b/fs/autofs4/autofs_i.h
@@ -52,7 +52,10 @@ struct autofs_info {
 
 	int		flags;
 
-	struct list_head rehash;
+	struct completion expire_complete;
+
+	struct list_head active;
+	struct list_head expiring;
 
 	struct autofs_sb_info *sbi;
 	unsigned long last_used;
@@ -68,15 +71,14 @@ struct autofs_info {
 };
 
 #define AUTOFS_INF_EXPIRING	(1<<0) /* dentry is in the process of expiring */
+#define AUTOFS_INF_MOUNTPOINT	(1<<1) /* mountpoint status for direct expire */
 
 struct autofs_wait_queue {
 	wait_queue_head_t queue;
 	struct autofs_wait_queue *next;
 	autofs_wqt_t wait_queue_token;
 	/* We use the following to see what we are waiting for */
-	unsigned int hash;
-	unsigned int len;
-	char *name;
+	struct qstr name;
 	u32 dev;
 	u64 ino;
 	uid_t uid;
@@ -85,7 +87,7 @@ struct autofs_wait_queue {
 	pid_t tgid;
 	/* This is for status reporting upon return */
 	int status;
-	atomic_t wait_ctr;
+	unsigned int wait_ctr;
 };
 
 #define AUTOFS_SBI_MAGIC 0x6d4a556d
@@ -112,8 +114,9 @@ struct autofs_sb_info {
 	struct mutex wq_mutex;
 	spinlock_t fs_lock;
 	struct autofs_wait_queue *queues; /* Wait queue pointer */
-	spinlock_t rehash_lock;
-	struct list_head rehash_list;
+	spinlock_t lookup_lock;
+	struct list_head active_list;
+	struct list_head expiring_list;
 };
 
 static inline struct autofs_sb_info *autofs4_sbi(struct super_block *sb)
@@ -138,18 +141,14 @@ static inline int autofs4_oz_mode(struct autofs_sb_info *sbi) {
 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;
 
-	if (inf) {
-		spin_lock(&inf->sbi->fs_lock);
-		pending = inf->flags & AUTOFS_INF_EXPIRING;
-		spin_unlock(&inf->sbi->fs_lock);
-	}
+	if (inf->flags & AUTOFS_INF_EXPIRING)
+		return 1;
 
-	return pending;
+	return 0;
 }
 
 static inline void autofs4_copy_atime(struct file *src, struct file *dst)
@@ -164,6 +163,7 @@ void autofs4_free_ino(struct autofs_info *);
 
 /* Expiration */
 int is_autofs4_dentry(struct dentry *);
+int autofs4_expire_wait(struct dentry *dentry);
 int autofs4_expire_run(struct super_block *, struct vfsmount *,
 			struct autofs_sb_info *,
 			struct autofs_packet_expire __user *);
diff --git a/fs/autofs4/expire.c b/fs/autofs4/expire.c
index 894fee54d4d..cdabb796ff0 100644
--- a/fs/autofs4/expire.c
+++ b/fs/autofs4/expire.c
@@ -259,13 +259,15 @@ static struct dentry *autofs4_expire_direct(struct super_block *sb,
 	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 */
+		if (d_mountpoint(root)) {
+			ino->flags |= AUTOFS_INF_MOUNTPOINT;
+			root->d_mounted--;
+		}
 		ino->flags |= AUTOFS_INF_EXPIRING;
+		init_completion(&ino->expire_complete);
 		spin_unlock(&sbi->fs_lock);
 		return root;
 	}
@@ -292,6 +294,8 @@ static struct dentry *autofs4_expire_indirect(struct super_block *sb,
 	struct list_head *next;
 	int do_now = how & AUTOFS_EXP_IMMEDIATE;
 	int exp_leaves = how & AUTOFS_EXP_LEAVES;
+	struct autofs_info *ino;
+	unsigned int ino_count;
 
 	if (!root)
 		return NULL;
@@ -316,6 +320,9 @@ static struct dentry *autofs4_expire_indirect(struct super_block *sb,
 		dentry = dget(dentry);
 		spin_unlock(&dcache_lock);
 
+		spin_lock(&sbi->fs_lock);
+		ino = autofs4_dentry_ino(dentry);
+
 		/*
 		 * Case 1: (i) indirect mount or top level pseudo direct mount
 		 *	   (autofs-4.1).
@@ -326,6 +333,11 @@ static struct dentry *autofs4_expire_indirect(struct super_block *sb,
 			DPRINTK("checking mountpoint %p %.*s",
 				dentry, (int)dentry->d_name.len, dentry->d_name.name);
 
+			/* Path walk currently on this dentry? */
+			ino_count = atomic_read(&ino->count) + 2;
+			if (atomic_read(&dentry->d_count) > ino_count)
+				goto next;
+
 			/* Can we umount this guy */
 			if (autofs4_mount_busy(mnt, dentry))
 				goto next;
@@ -343,23 +355,25 @@ static struct dentry *autofs4_expire_indirect(struct super_block *sb,
 
 		/* Case 2: tree mount, expire iff entire tree is not busy */
 		if (!exp_leaves) {
-			/* 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);
+			/* Path walk currently on this dentry? */
+			ino_count = atomic_read(&ino->count) + 1;
+			if (atomic_read(&dentry->d_count) > ino_count)
+				goto next;
 
-				/* Set this flag early to catch sys_chdir and the like */
-				inf->flags |= AUTOFS_INF_EXPIRING;
-				spin_unlock(&sbi->fs_lock);
+			if (!autofs4_tree_busy(mnt, dentry, timeout, do_now)) {
 				expired = dentry;
 				goto found;
 			}
-			spin_unlock(&sbi->fs_lock);
 		/*
 		 * Case 3: pseudo direct mount, expire individual leaves
 		 *	   (autofs-4.1).
 		 */
 		} else {
+			/* Path walk currently on this dentry? */
+			ino_count = atomic_read(&ino->count) + 1;
+			if (atomic_read(&dentry->d_count) > ino_count)
+				goto next;
+
 			expired = autofs4_check_leaves(mnt, dentry, timeout, do_now);
 			if (expired) {
 				dput(dentry);
@@ -367,6 +381,7 @@ static struct dentry *autofs4_expire_indirect(struct super_block *sb,
 			}
 		}
 next:
+		spin_unlock(&sbi->fs_lock);
 		dput(dentry);
 		spin_lock(&dcache_lock);
 		next = next->next;
@@ -377,12 +392,45 @@ next:
 found:
 	DPRINTK("returning %p %.*s",
 		expired, (int)expired->d_name.len, expired->d_name.name);
+	ino = autofs4_dentry_ino(expired);
+	ino->flags |= AUTOFS_INF_EXPIRING;
+	init_completion(&ino->expire_complete);
+	spin_unlock(&sbi->fs_lock);
 	spin_lock(&dcache_lock);
 	list_move(&expired->d_parent->d_subdirs, &expired->d_u.d_child);
 	spin_unlock(&dcache_lock);
 	return expired;
 }
 
+int autofs4_expire_wait(struct dentry *dentry)
+{
+	struct autofs_sb_info *sbi = autofs4_sbi(dentry->d_sb);
+	struct autofs_info *ino = autofs4_dentry_ino(dentry);
+	int status;
+
+	/* Block on any pending expire */
+	spin_lock(&sbi->fs_lock);
+	if (ino->flags & AUTOFS_INF_EXPIRING) {
+		spin_unlock(&sbi->fs_lock);
+
+		DPRINTK("waiting for expire %p name=%.*s",
+			 dentry, dentry->d_name.len, dentry->d_name.name);
+
+		status = autofs4_wait(sbi, dentry, NFY_NONE);
+		wait_for_completion(&ino->expire_complete);
+
+		DPRINTK("expire done status=%d", status);
+
+		if (d_unhashed(dentry))
+			return -EAGAIN;
+
+		return status;
+	}
+	spin_unlock(&sbi->fs_lock);
+
+	return 0;
+}
+
 /* Perform an expiry operation */
 int autofs4_expire_run(struct super_block *sb,
 		      struct vfsmount *mnt,
@@ -390,7 +438,9 @@ int autofs4_expire_run(struct super_block *sb,
 		      struct autofs_packet_expire __user *pkt_p)
 {
 	struct autofs_packet_expire pkt;
+	struct autofs_info *ino;
 	struct dentry *dentry;
+	int ret = 0;
 
 	memset(&pkt,0,sizeof pkt);
 
@@ -406,9 +456,15 @@ int autofs4_expire_run(struct super_block *sb,
 	dput(dentry);
 
 	if ( copy_to_user(pkt_p, &pkt, sizeof(struct autofs_packet_expire)) )
-		return -EFAULT;
+		ret = -EFAULT;
 
-	return 0;
+	spin_lock(&sbi->fs_lock);
+	ino = autofs4_dentry_ino(dentry);
+	ino->flags &= ~AUTOFS_INF_EXPIRING;
+	complete_all(&ino->expire_complete);
+	spin_unlock(&sbi->fs_lock);
+
+	return ret;
 }
 
 /* Call repeatedly until it returns -EAGAIN, meaning there's nothing
@@ -433,9 +489,16 @@ int autofs4_expire_multi(struct super_block *sb, struct vfsmount *mnt,
 
 		/* This is synchronous because it makes the daemon a
                    little easier */
-		ino->flags |= AUTOFS_INF_EXPIRING;
 		ret = autofs4_wait(sbi, dentry, NFY_EXPIRE);
+
+		spin_lock(&sbi->fs_lock);
+		if (ino->flags & AUTOFS_INF_MOUNTPOINT) {
+			sb->s_root->d_mounted++;
+			ino->flags &= ~AUTOFS_INF_MOUNTPOINT;
+		}
 		ino->flags &= ~AUTOFS_INF_EXPIRING;
+		complete_all(&ino->expire_complete);
+		spin_unlock(&sbi->fs_lock);
 		dput(dentry);
 	}
 
diff --git a/fs/autofs4/inode.c b/fs/autofs4/inode.c
index 2fdcf5e1d23..7bb3e5ba053 100644
--- a/fs/autofs4/inode.c
+++ b/fs/autofs4/inode.c
@@ -24,8 +24,10 @@
 
 static void ino_lnkfree(struct autofs_info *ino)
 {
-	kfree(ino->u.symlink);
-	ino->u.symlink = NULL;
+	if (ino->u.symlink) {
+		kfree(ino->u.symlink);
+		ino->u.symlink = NULL;
+	}
 }
 
 struct autofs_info *autofs4_init_ino(struct autofs_info *ino,
@@ -41,16 +43,18 @@ struct autofs_info *autofs4_init_ino(struct autofs_info *ino,
 	if (ino == NULL)
 		return NULL;
 
-	ino->flags = 0;
-	ino->mode = mode;
-	ino->inode = NULL;
-	ino->dentry = NULL;
-	ino->size = 0;
-
-	INIT_LIST_HEAD(&ino->rehash);
+	if (!reinit) {
+		ino->flags = 0;
+		ino->inode = NULL;
+		ino->dentry = NULL;
+		ino->size = 0;
+		INIT_LIST_HEAD(&ino->active);
+		INIT_LIST_HEAD(&ino->expiring);
+		atomic_set(&ino->count, 0);
+	}
 
+	ino->mode = mode;
 	ino->last_used = jiffies;
-	atomic_set(&ino->count, 0);
 
 	ino->sbi = sbi;
 
@@ -159,8 +163,8 @@ void autofs4_kill_sb(struct super_block *sb)
 	if (!sbi)
 		goto out_kill_sb;
 
-	if (!sbi->catatonic)
-		autofs4_catatonic_mode(sbi); /* Free wait queues, close pipe */
+	/* Free wait queues, close pipe */
+	autofs4_catatonic_mode(sbi);
 
 	/* Clean up and release dangling references */
 	autofs4_force_release(sbi);
@@ -338,8 +342,9 @@ int autofs4_fill_super(struct super_block *s, void *data, int silent)
 	mutex_init(&sbi->wq_mutex);
 	spin_lock_init(&sbi->fs_lock);
 	sbi->queues = NULL;
-	spin_lock_init(&sbi->rehash_lock);
-	INIT_LIST_HEAD(&sbi->rehash_list);
+	spin_lock_init(&sbi->lookup_lock);
+	INIT_LIST_HEAD(&sbi->active_list);
+	INIT_LIST_HEAD(&sbi->expiring_list);
 	s->s_blocksize = 1024;
 	s->s_blocksize_bits = 10;
 	s->s_magic = AUTOFS_SUPER_MAGIC;
diff --git a/fs/autofs4/root.c b/fs/autofs4/root.c
index edf5b6bddb5..bcfb2dc0a61 100644
--- a/fs/autofs4/root.c
+++ b/fs/autofs4/root.c
@@ -25,25 +25,25 @@ static int autofs4_dir_rmdir(struct inode *,struct dentry *);
 static int autofs4_dir_mkdir(struct inode *,struct dentry *,int);
 static int autofs4_root_ioctl(struct inode *, struct file *,unsigned int,unsigned long);
 static int autofs4_dir_open(struct inode *inode, struct file *file);
-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_lookup(struct inode *,struct dentry *, struct nameidata *);
 static void *autofs4_follow_link(struct dentry *, struct nameidata *);
 
+#define TRIGGER_FLAGS   (LOOKUP_CONTINUE | LOOKUP_DIRECTORY)
+#define TRIGGER_INTENTS (LOOKUP_OPEN | LOOKUP_CREATE)
+
 const struct file_operations autofs4_root_operations = {
 	.open		= dcache_dir_open,
 	.release	= dcache_dir_close,
 	.read		= generic_read_dir,
-	.readdir	= autofs4_root_readdir,
+	.readdir	= dcache_readdir,
 	.ioctl		= autofs4_root_ioctl,
 };
 
 const struct file_operations autofs4_dir_operations = {
 	.open		= autofs4_dir_open,
-	.release	= autofs4_dir_close,
+	.release	= dcache_dir_close,
 	.read		= generic_read_dir,
-	.readdir	= autofs4_dir_readdir,
+	.readdir	= dcache_readdir,
 };
 
 const struct inode_operations autofs4_indirect_root_inode_operations = {
@@ -70,42 +70,10 @@ const struct inode_operations autofs4_dir_inode_operations = {
 	.rmdir		= autofs4_dir_rmdir,
 };
 
-static int autofs4_root_readdir(struct file *file, void *dirent,
-				filldir_t filldir)
-{
-	struct autofs_sb_info *sbi = autofs4_sbi(file->f_path.dentry->d_sb);
-	int oz_mode = autofs4_oz_mode(sbi);
-
-	DPRINTK("called, filp->f_pos = %lld", file->f_pos);
-
-	/*
-	 * Don't set reghost flag if:
-	 * 1) f_pos is larger than zero -- we've already been here.
-	 * 2) we haven't even enabled reghosting in the 1st place.
-	 * 3) this is the daemon doing a readdir
-	 */
-	if (oz_mode && file->f_pos == 0 && sbi->reghost_enabled)
-		sbi->needs_reghost = 1;
-
-	DPRINTK("needs_reghost = %d", sbi->needs_reghost);
-
-	return dcache_readdir(file, dirent, filldir);
-}
-
 static int autofs4_dir_open(struct inode *inode, struct file *file)
 {
 	struct dentry *dentry = file->f_path.dentry;
-	struct vfsmount *mnt = file->f_path.mnt;
 	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);
@@ -113,159 +81,32 @@ static int autofs4_dir_open(struct inode *inode, struct file *file)
 	if (autofs4_oz_mode(sbi))
 		goto out;
 
-	if (autofs4_ispending(dentry)) {
-		DPRINTK("dentry busy");
-		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, ret;
-
-		/* In case there are stale directory dentrys from a failed mount */
-		spin_lock(&dcache_lock);
-		empty = list_empty(&dentry->d_subdirs);
+	/*
+	 * An empty directory in an autofs file system is always a
+	 * mount point. The daemon must have failed to mount this
+	 * during lookup so it doesn't exist. This can happen, for
+	 * example, if user space returns an incorrect status for a
+	 * mount request. Otherwise we're doing a readdir on the
+	 * autofs file system so just let the libfs routines handle
+	 * it.
+	 */
+	spin_lock(&dcache_lock);
+	if (!d_mountpoint(dentry) && __simple_empty(dentry)) {
 		spin_unlock(&dcache_lock);
-
-		if (!empty)
-			d_invalidate(dentry);
-
-		nd.flags = LOOKUP_DIRECTORY;
-		ret = (dentry->d_op->d_revalidate)(dentry, &nd);
-
-		if (ret <= 0) {
-			if (ret < 0)
-				status = ret;
-			dcache_dir_close(inode, file);
-			goto out;
-		}
+		return -ENOENT;
 	}
+	spin_unlock(&dcache_lock);
 
-	if (d_mountpoint(dentry)) {
-		struct file *fp = NULL;
-		struct path fp_path = { .dentry = dentry, .mnt = mnt };
-
-		path_get(&fp_path);
-
-		if (!autofs4_follow_mount(&fp_path.mnt, &fp_path.dentry)) {
-			path_put(&fp_path);
-			dcache_dir_close(inode, file);
-			goto out;
-		}
-
-		fp = dentry_open(fp_path.dentry, fp_path.mnt, file->f_flags);
-		status = PTR_ERR(fp);
-		if (IS_ERR(fp)) {
-			dcache_dir_close(inode, file);
-			goto out;
-		}
-		cursor->d_fsdata = fp;
-	}
-	return 0;
-out:
-	return status;
-}
-
-static int autofs4_dir_close(struct inode *inode, struct file *file)
-{
-	struct dentry *dentry = file->f_path.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);
-
-	if (autofs4_oz_mode(sbi))
-		goto out;
-
-	if (autofs4_ispending(dentry)) {
-		DPRINTK("dentry busy");
-		status = -EBUSY;
-		goto out;
-	}
-
-	if (d_mountpoint(dentry)) {
-		struct file *fp = cursor->d_fsdata;
-		if (!fp) {
-			status = -ENOENT;
-			goto out;
-		}
-		filp_close(fp, current->files);
-	}
-out:
-	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_path.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",
-		file, dentry, dentry->d_name.len, dentry->d_name.name);
-
-	if (autofs4_oz_mode(sbi))
-		goto out;
-
-	if (autofs4_ispending(dentry)) {
-		DPRINTK("dentry busy");
-		return -EBUSY;
-	}
-
-	if (d_mountpoint(dentry)) {
-		struct file *fp = cursor->d_fsdata;
-
-		if (!fp)
-			return -ENOENT;
-
-		if (!fp->f_op || !fp->f_op->readdir)
-			goto out;
-
-		status = vfs_readdir(fp, filldir, dirent);
-		file->f_pos = fp->f_pos;
-		if (status)
-			autofs4_copy_atime(file, fp);
-		return status;
-	}
 out:
-	return dcache_readdir(file, dirent, filldir);
+	return dcache_dir_open(inode, file);
 }
 
 static int try_to_fill_dentry(struct dentry *dentry, int flags)
 {
 	struct autofs_sb_info *sbi = autofs4_sbi(dentry->d_sb);
 	struct autofs_info *ino = autofs4_dentry_ino(dentry);
-	struct dentry *new;
 	int status;
 
-	/* Block on any pending expiry here; invalidate the dentry
-           when expiration is done to trigger mount request with a new
-           dentry */
-	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);
-
-		/*
-		 * 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 -EAGAIN;
-	}
-
 	DPRINTK("dentry=%p %.*s ino=%p",
 		 dentry, dentry->d_name.len, dentry->d_name.name, dentry->d_inode);
 
@@ -292,7 +133,8 @@ static int try_to_fill_dentry(struct dentry *dentry, int flags)
 			return status;
 		}
 	/* Trigger mount for path component or follow link */
-	} else if (flags & (LOOKUP_CONTINUE | LOOKUP_DIRECTORY) ||
+	} else if (dentry->d_flags & DCACHE_AUTOFS_PENDING ||
+			flags & (TRIGGER_FLAGS | TRIGGER_INTENTS) ||
 			current->link_count) {
 		DPRINTK("waiting for mount name=%.*s",
 			dentry->d_name.len, dentry->d_name.name);
@@ -320,26 +162,6 @@ static int try_to_fill_dentry(struct dentry *dentry, int flags)
 	dentry->d_flags &= ~DCACHE_AUTOFS_PENDING;
 	spin_unlock(&dentry->d_lock);
 
-	/*
-	 * The dentry that is passed in from lookup may not be the one
-	 * we end up using, as mkdir can create a new one.  If this
-	 * happens, and another process tries the lookup at the same time,
-	 * it will set the PENDING flag on this new dentry, but add itself
-	 * to our waitq.  Then, if after the lookup succeeds, the first
-	 * process that requested the mount performs another lookup of the
-	 * same directory, it will show up as still pending!  So, we need
-	 * to redo the lookup here and clear pending on that dentry.
-	 */
-	if (d_unhashed(dentry)) {
-		new = d_lookup(dentry->d_parent, &dentry->d_name);
-		if (new) {
-			spin_lock(&new->d_lock);
-			new->d_flags &= ~DCACHE_AUTOFS_PENDING;
-			spin_unlock(&new->d_lock);
-			dput(new);
-		}
-	}
-
 	return 0;
 }
 
@@ -355,51 +177,63 @@ static void *autofs4_follow_link(struct dentry *dentry, struct nameidata *nd)
 	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)
+	/*
+	 * For an expire of a covered direct or offset mount we need
+	 * to beeak out of follow_down() at the autofs mount trigger
+	 * (d_mounted--), so we can see the expiring flag, and manage
+	 * the blocking and following here until the expire is completed.
+	 */
+	if (oz_mode) {
+		spin_lock(&sbi->fs_lock);
+		if (ino->flags & AUTOFS_INF_EXPIRING) {
+			spin_unlock(&sbi->fs_lock);
+			/* Follow down to our covering mount. */
+			if (!follow_down(&nd->path.mnt, &nd->path.dentry))
+				goto done;
+			goto follow;
+		}
+		spin_unlock(&sbi->fs_lock);
 		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);
+	/* If an expire request is pending everyone must wait. */
+	autofs4_expire_wait(dentry);
 
-		DPRINTK("request done status=%d", status);
-	}
+	/* We trigger a mount for almost all flags */
+	lookup_type = nd->flags & (TRIGGER_FLAGS | TRIGGER_INTENTS);
+	if (!(lookup_type || dentry->d_flags & DCACHE_AUTOFS_PENDING))
+		goto follow;
 
 	/*
-	 * 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.
+	 * 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)) {
+	if (dentry->d_flags & DCACHE_AUTOFS_PENDING ||
+	    (!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->path.mnt,
-						  &nd->path.dentry)) {
-				status = -ENOENT;
-				goto out_error;
-			}
-		}
-
-		goto done;
+		goto follow;
 	}
 	spin_unlock(&dcache_lock);
+follow:
+	/*
+	 * If there is no root mount it m