1 files changed, 78 insertions, 95 deletions

diff --git a/fs/autofs4/root.c b/fs/autofs4/root.c
index 014e7aba3b0..cc87c1abac9 100644
--- a/fs/autofs4/root.c
+++ b/fs/autofs4/root.c
@@ -23,27 +23,25 @@
 
 #include "autofs_i.h"
 
-DEFINE_SPINLOCK(autofs4_lock);
-
 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 *);
-static int autofs4_dir_mkdir(struct inode *,struct dentry *,int);
+static int autofs4_dir_mkdir(struct inode *,struct dentry *,umode_t);
 static long autofs4_root_ioctl(struct file *,unsigned int,unsigned long);
 #ifdef CONFIG_COMPAT
 static long autofs4_root_compat_ioctl(struct file *,unsigned int,unsigned long);
 #endif
 static int autofs4_dir_open(struct inode *inode, struct file *file);
-static struct dentry *autofs4_lookup(struct inode *,struct dentry *, struct nameidata *);
+static struct dentry *autofs4_lookup(struct inode *,struct dentry *, unsigned int);
 static struct vfsmount *autofs4_d_automount(struct path *);
-static int autofs4_d_manage(struct dentry *, bool, bool);
+static int autofs4_d_manage(struct dentry *, bool);
 static void autofs4_dentry_release(struct dentry *);
 
 const struct file_operations autofs4_root_operations = {
 	.open		= dcache_dir_open,
 	.release	= dcache_dir_close,
 	.read		= generic_read_dir,
-	.readdir	= dcache_readdir,
+	.iterate	= dcache_readdir,
 	.llseek		= dcache_dir_lseek,
 	.unlocked_ioctl	= autofs4_root_ioctl,
 #ifdef CONFIG_COMPAT
@@ -55,7 +53,7 @@ const struct file_operations autofs4_dir_operations = {
 	.open		= autofs4_dir_open,
 	.release	= dcache_dir_close,
 	.read		= generic_read_dir,
-	.readdir	= dcache_readdir,
+	.iterate	= dcache_readdir,
 	.llseek		= dcache_dir_lseek,
 };
 
@@ -125,15 +123,12 @@ static int autofs4_dir_open(struct inode *inode, struct file *file)
 	 * autofs file system so just let the libfs routines handle
 	 * it.
 	 */
-	spin_lock(&autofs4_lock);
-	spin_lock(&dentry->d_lock);
-	if (!d_mountpoint(dentry) && list_empty(&dentry->d_subdirs)) {
-		spin_unlock(&dentry->d_lock);
-		spin_unlock(&autofs4_lock);
+	spin_lock(&sbi->lookup_lock);
+	if (!d_mountpoint(dentry) && simple_empty(dentry)) {
+		spin_unlock(&sbi->lookup_lock);
 		return -ENOENT;
 	}
-	spin_unlock(&dentry->d_lock);
-	spin_unlock(&autofs4_lock);
+	spin_unlock(&sbi->lookup_lock);
 
 out:
 	return dcache_dir_open(inode, file);
@@ -171,7 +166,6 @@ static struct dentry *autofs4_lookup_active(struct dentry *dentry)
 	const unsigned char *str = name->name;
 	struct list_head *p, *head;
 
-	spin_lock(&autofs4_lock);
 	spin_lock(&sbi->lookup_lock);
 	head = &sbi->active_list;
 	list_for_each(p, head) {
@@ -185,7 +179,7 @@ static struct dentry *autofs4_lookup_active(struct dentry *dentry)
 		spin_lock(&active->d_lock);
 
 		/* Already gone? */
-		if (active->d_count == 0)
+		if ((int) d_count(active) <= 0)
 			goto next;
 
 		qstr = &active->d_name;
@@ -204,14 +198,12 @@ static struct dentry *autofs4_lookup_active(struct dentry *dentry)
 			dget_dlock(active);
 			spin_unlock(&active->d_lock);
 			spin_unlock(&sbi->lookup_lock);
-			spin_unlock(&autofs4_lock);
 			return active;
 		}
 next:
 		spin_unlock(&active->d_lock);
 	}
 	spin_unlock(&sbi->lookup_lock);
-	spin_unlock(&autofs4_lock);
 
 	return NULL;
 }
@@ -226,7 +218,6 @@ static struct dentry *autofs4_lookup_expiring(struct dentry *dentry)
 	const unsigned char *str = name->name;
 	struct list_head *p, *head;
 
-	spin_lock(&autofs4_lock);
 	spin_lock(&sbi->lookup_lock);
 	head = &sbi->expiring_list;
 	list_for_each(p, head) {
@@ -239,7 +230,7 @@ static struct dentry *autofs4_lookup_expiring(struct dentry *dentry)
 
 		spin_lock(&expiring->d_lock);
 
-		/* Bad luck, we've already been dentry_iput */
+		/* We've already been dentry_iput or unlinked */
 		if (!expiring->d_inode)
 			goto next;
 
@@ -259,14 +250,12 @@ static struct dentry *autofs4_lookup_expiring(struct dentry *dentry)
 			dget_dlock(expiring);
 			spin_unlock(&expiring->d_lock);
 			spin_unlock(&sbi->lookup_lock);
-			spin_unlock(&autofs4_lock);
 			return expiring;
 		}
 next:
 		spin_unlock(&expiring->d_lock);
 	}
 	spin_unlock(&sbi->lookup_lock);
-	spin_unlock(&autofs4_lock);
 
 	return NULL;
 }
@@ -275,17 +264,16 @@ static int autofs4_mount_wait(struct dentry *dentry)
 {
 	struct autofs_sb_info *sbi = autofs4_sbi(dentry->d_sb);
 	struct autofs_info *ino = autofs4_dentry_ino(dentry);
-	int status;
+	int status = 0;
 
 	if (ino->flags & AUTOFS_INF_PENDING) {
 		DPRINTK("waiting for mount name=%.*s",
 			dentry->d_name.len, dentry->d_name.name);
 		status = autofs4_wait(sbi, dentry, NFY_MOUNT);
 		DPRINTK("mount wait done status=%d", status);
-		ino->last_used = jiffies;
-		return status;
 	}
-	return 0;
+	ino->last_used = jiffies;
+	return status;
 }
 
 static int do_expire_wait(struct dentry *dentry)
@@ -319,9 +307,12 @@ static struct dentry *autofs4_mountpoint_changed(struct path *path)
 	 */
 	if (autofs_type_indirect(sbi->type) && d_unhashed(dentry)) {
 		struct dentry *parent = dentry->d_parent;
+		struct autofs_info *ino;
 		struct dentry *new = d_lookup(parent, &dentry->d_name);
 		if (!new)
 			return NULL;
+		ino = autofs4_dentry_ino(new);
+		ino->last_used = jiffies;
 		dput(path->dentry);
 		path->dentry = new;
 	}
@@ -338,18 +329,6 @@ static struct vfsmount *autofs4_d_automount(struct path *path)
 	DPRINTK("dentry=%p %.*s",
 		dentry, dentry->d_name.len, dentry->d_name.name);
 
-	/*
-	 * Someone may have manually umounted this or it was a submount
-	 * that has gone away.
-	 */
-	spin_lock(&dentry->d_lock);
-	if (!d_mountpoint(dentry) && list_empty(&dentry->d_subdirs)) {
-		if (!(dentry->d_flags & DCACHE_MANAGE_TRANSIT) &&
-		     (dentry->d_flags & DCACHE_NEED_AUTOMOUNT))
-			__managed_dentry_set_transit(path->dentry);
-	}
-	spin_unlock(&dentry->d_lock);
-
 	/* The daemon never triggers a mount. */
 	if (autofs4_oz_mode(sbi))
 		return NULL;
@@ -373,7 +352,6 @@ static struct vfsmount *autofs4_d_automount(struct path *path)
 		status = autofs4_mount_wait(dentry);
 		if (status)
 			return ERR_PTR(status);
-		spin_lock(&sbi->fs_lock);
 		goto done;
 	}
 
@@ -382,8 +360,11 @@ static struct vfsmount *autofs4_d_automount(struct path *path)
 	 * having d_mountpoint() true, so there's no need to call back
 	 * to the daemon.
 	 */
-	if (dentry->d_inode && S_ISLNK(dentry->d_inode->i_mode))
+	if (dentry->d_inode && S_ISLNK(dentry->d_inode->i_mode)) {
+		spin_unlock(&sbi->fs_lock);
 		goto done;
+	}
+
 	if (!d_mountpoint(dentry)) {
 		/*
 		 * It's possible that user space hasn't removed directories
@@ -397,47 +378,28 @@ static struct vfsmount *autofs4_d_automount(struct path *path)
 		 * require user space behave.
 		 */
 		if (sbi->version > 4) {
-			if (have_submounts(dentry))
+			if (have_submounts(dentry)) {
+				spin_unlock(&sbi->fs_lock);
 				goto done;
+			}
 		} else {
-			spin_lock(&dentry->d_lock);
-			if (!list_empty(&dentry->d_subdirs)) {
-				spin_unlock(&dentry->d_lock);
+			if (!simple_empty(dentry)) {
+				spin_unlock(&sbi->fs_lock);
 				goto done;
 			}
-			spin_unlock(&dentry->d_lock);
 		}
 		ino->flags |= AUTOFS_INF_PENDING;
 		spin_unlock(&sbi->fs_lock);
 		status = autofs4_mount_wait(dentry);
-		if (status)
-			return ERR_PTR(status);
 		spin_lock(&sbi->fs_lock);
 		ino->flags &= ~AUTOFS_INF_PENDING;
-	}
-done:
-	if (!(ino->flags & AUTOFS_INF_EXPIRING)) {
-		/*
-		 * Any needed mounting has been completed and the path updated
-		 * so turn this into a normal dentry so we don't continually
-		 * call ->d_automount() and ->d_manage().
-		 */
-		spin_lock(&dentry->d_lock);
-		__managed_dentry_clear_transit(dentry);
-		/*
-		 * Only clear DMANAGED_AUTOMOUNT for rootless multi-mounts and
-		 * symlinks as in all other cases the dentry will be covered by
-		 * an actual mount so ->d_automount() won't be called during
-		 * the follow.
-		 */
-		if ((!d_mountpoint(dentry) &&
-		    !list_empty(&dentry->d_subdirs)) ||
-		    (dentry->d_inode && S_ISLNK(dentry->d_inode->i_mode)))
-			__managed_dentry_clear_automount(dentry);
-		spin_unlock(&dentry->d_lock);
+		if (status) {
+			spin_unlock(&sbi->fs_lock);
+			return ERR_PTR(status);
+		}
 	}
 	spin_unlock(&sbi->fs_lock);
-
+done:
 	/* Mount succeeded, check if we ended up with a new dentry */
 	dentry = autofs4_mountpoint_changed(path);
 	if (!dentry)
@@ -446,15 +408,19 @@ done:
 	return NULL;
 }
 
-int autofs4_d_manage(struct dentry *dentry, bool mounting_here, bool rcu_walk)
+static int autofs4_d_manage(struct dentry *dentry, bool rcu_walk)
 {
 	struct autofs_sb_info *sbi = autofs4_sbi(dentry->d_sb);
+	struct autofs_info *ino = autofs4_dentry_ino(dentry);
+	int status;
 
 	DPRINTK("dentry=%p %.*s",
 		dentry, dentry->d_name.len, dentry->d_name.name);
 
 	/* The daemon never waits. */
-	if (autofs4_oz_mode(sbi) || mounting_here) {
+	if (autofs4_oz_mode(sbi)) {
+		if (rcu_walk)
+			return 0;
 		if (!d_mountpoint(dentry))
 			return -EISDIR;
 		return 0;
@@ -471,11 +437,36 @@ int autofs4_d_manage(struct dentry *dentry, bool mounting_here, bool rcu_walk)
 	 * This dentry may be under construction so wait on mount
 	 * completion.
 	 */
-	return autofs4_mount_wait(dentry);
+	status = autofs4_mount_wait(dentry);
+	if (status)
+		return status;
+
+	spin_lock(&sbi->fs_lock);
+	/*
+	 * If the dentry has been selected for expire while we slept
+	 * on the lock then it might go away. We'll deal with that in
+	 * ->d_automount() and wait on a new mount if the expire
+	 * succeeds or return here if it doesn't (since there's no
+	 * mount to follow with a rootless multi-mount).
+	 */
+	if (!(ino->flags & AUTOFS_INF_EXPIRING)) {
+		/*
+		 * Any needed mounting has been completed and the path
+		 * updated so check if this is a rootless multi-mount so
+		 * we can avoid needless calls ->d_automount() and avoid
+		 * an incorrect ELOOP error return.
+		 */
+		if ((!d_mountpoint(dentry) && !simple_empty(dentry)) ||
+		    (dentry->d_inode && S_ISLNK(dentry->d_inode->i_mode)))
+			status = -EISDIR;
+	}
+	spin_unlock(&sbi->fs_lock);
+
+	return status;
 }
 
 /* Lookups in the root directory */
-static struct dentry *autofs4_lookup(struct inode *dir, struct dentry *dentry, struct nameidata *nd)
+static struct dentry *autofs4_lookup(struct inode *dir, struct dentry *dentry, unsigned int flags)
 {
 	struct autofs_sb_info *sbi;
 	struct autofs_info *ino;
@@ -567,7 +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;
@@ -598,11 +589,11 @@ static int autofs4_dir_unlink(struct inode *dir, struct dentry *dentry)
 	
 	/* This allows root to remove symlinks */
 	if (!autofs4_oz_mode(sbi) && !capable(CAP_SYS_ADMIN))
-		return -EACCES;
+		return -EPERM;
 
 	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);
@@ -612,12 +603,10 @@ static int autofs4_dir_unlink(struct inode *dir, struct dentry *dentry)
 
 	dir->i_mtime = CURRENT_TIME;
 
-	spin_lock(&autofs4_lock);
-	autofs4_add_expiring(dentry);
-	spin_lock(&dentry->d_lock);
-	__d_drop(dentry);
-	spin_unlock(&dentry->d_lock);
-	spin_unlock(&autofs4_lock);
+	spin_lock(&sbi->lookup_lock);
+	__autofs4_add_expiring(dentry);
+	d_drop(dentry);
+	spin_unlock(&sbi->lookup_lock);
 
 	return 0;
 }
@@ -629,7 +618,7 @@ static int autofs4_dir_unlink(struct inode *dir, struct dentry *dentry)
  * set the DMANAGED_AUTOMOUNT and DMANAGED_TRANSIT flags on the leaves
  * of the directory tree. There is no need to clear the automount flag
  * following a mount or restore it after an expire because these mounts
- * are always covered. However, it is neccessary to ensure that these
+ * are always covered. However, it is necessary to ensure that these
  * flags are clear on non-empty directories to avoid unnecessary calls
  * during path walks.
  */
@@ -686,20 +675,14 @@ static int autofs4_dir_rmdir(struct inode *dir, struct dentry *dentry)
 	if (!autofs4_oz_mode(sbi))
 		return -EACCES;
 
-	spin_lock(&autofs4_lock);
 	spin_lock(&sbi->lookup_lock);
-	spin_lock(&dentry->d_lock);
-	if (!list_empty(&dentry->d_subdirs)) {
-		spin_unlock(&dentry->d_lock);
+	if (!simple_empty(dentry)) {
 		spin_unlock(&sbi->lookup_lock);
-		spin_unlock(&autofs4_lock);
 		return -ENOTEMPTY;
 	}
 	__autofs4_add_expiring(dentry);
+	d_drop(dentry);
 	spin_unlock(&sbi->lookup_lock);
-	__d_drop(dentry);
-	spin_unlock(&dentry->d_lock);
-	spin_unlock(&autofs4_lock);
 
 	if (sbi->version < 5)
 		autofs_clear_leaf_automount_flags(dentry);
@@ -719,7 +702,7 @@ static int autofs4_dir_rmdir(struct inode *dir, struct dentry *dentry)
 	return 0;
 }
 
-static int autofs4_dir_mkdir(struct inode *dir, struct dentry *dentry, int mode)
+static int autofs4_dir_mkdir(struct inode *dir, struct dentry *dentry, umode_t mode)
 {
 	struct autofs_sb_info *sbi = autofs4_sbi(dir->i_sb);
 	struct autofs_info *ino = autofs4_dentry_ino(dentry);
@@ -749,7 +732,7 @@ static int autofs4_dir_mkdir(struct inode *dir, struct dentry *dentry, int mode)
 	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;
@@ -893,7 +876,7 @@ static int autofs4_root_ioctl_unlocked(struct inode *inode, struct file *filp,
 static long autofs4_root_ioctl(struct file *filp,
 			       unsigned int cmd, unsigned long arg)
 {
-	struct inode *inode = filp->f_dentry->d_inode;
+	struct inode *inode = file_inode(filp);
 	return autofs4_root_ioctl_unlocked(inode, filp, cmd, arg);
 }
 
@@ -901,7 +884,7 @@ static long autofs4_root_ioctl(struct file *filp,
 static long autofs4_root_compat_ioctl(struct file *filp,
 			     unsigned int cmd, unsigned long arg)
 {
-	struct inode *inode = filp->f_path.dentry->d_inode;
+	struct inode *inode = file_inode(filp);
 	int ret;
 
 	if (cmd == AUTOFS_IOC_READY || cmd == AUTOFS_IOC_FAIL)