5 files changed, 35 insertions, 11 deletions

diff --git a/drivers/usb/core/inode.c b/drivers/usb/core/inode.c
index 4a6366a42129..111a01a747fc 100644
--- a/drivers/usb/core/inode.c
+++ b/drivers/usb/core/inode.c
@@ -380,6 +380,7 @@ static int usbfs_rmdir(struct inode *dir, struct dentry *dentry)
         mutex_lock(&inode->i_mutex);
         dentry_unhash(dentry);
         if (usbfs_empty(dentry)) {
+                dont_mount(dentry);
                 drop_nlink(dentry->d_inode);
                 drop_nlink(dentry->d_inode);
                 dput(dentry);
diff --git a/fs/configfs/dir.c b/fs/configfs/dir.c
index 8e48b52205aa..0b502f80c691 100644
--- a/fs/configfs/dir.c
+++ b/fs/configfs/dir.c
@@ -645,6 +645,7 @@ static void detach_groups(struct config_group *group)
 
                 configfs_detach_group(sd->s_element);
                 child->d_inode->i_flags |= S_DEAD;
+                dont_mount(child);
 
                 mutex_unlock(&child->d_inode->i_mutex);
 
@@ -840,6 +841,7 @@ static int configfs_attach_item(struct config_item *parent_item,
                         mutex_lock(&dentry->d_inode->i_mutex);
                         configfs_remove_dir(item);
                         dentry->d_inode->i_flags |= S_DEAD;
+                        dont_mount(dentry);
                         mutex_unlock(&dentry->d_inode->i_mutex);
                         d_delete(dentry);
                 }
@@ -882,6 +884,7 @@ static int configfs_attach_group(struct config_item *parent_item,
                 if (ret) {
                         configfs_detach_item(item);
                         dentry->d_inode->i_flags |= S_DEAD;
+                        dont_mount(dentry);
                 }
                 configfs_adjust_dir_dirent_depth_after_populate(sd);
                 mutex_unlock(&dentry->d_inode->i_mutex);
@@ -1725,6 +1728,7 @@ void configfs_unregister_subsystem(struct configfs_subsystem *subsys)
         mutex_unlock(&configfs_symlink_mutex);
         configfs_detach_group(&group->cg_item);
         dentry->d_inode->i_flags |= S_DEAD;
+        dont_mount(dentry);
         mutex_unlock(&dentry->d_inode->i_mutex);
 
         d_delete(dentry);
diff --git a/fs/namei.c b/fs/namei.c
index 16df7277a92e..b86b96fe1dc3 100644
--- a/fs/namei.c
+++ b/fs/namei.c
@@ -2176,8 +2176,10 @@ int vfs_rmdir(struct inode *dir, struct dentry *dentry)
                 error = security_inode_rmdir(dir, dentry);
                 if (!error) {
                         error = dir->i_op->rmdir(dir, dentry);
-                        if (!error)
+                        if (!error) {
                                 dentry->d_inode->i_flags |= S_DEAD;
+                                dont_mount(dentry);
+                        }
                 }
         }
         mutex_unlock(&dentry->d_inode->i_mutex);
@@ -2261,7 +2263,7 @@ int vfs_unlink(struct inode *dir, struct dentry *dentry)
                 if (!error) {
                         error = dir->i_op->unlink(dir, dentry);
                         if (!error)
-                                dentry->d_inode->i_flags |= S_DEAD;
+                                dont_mount(dentry);
                 }
         }
         mutex_unlock(&dentry->d_inode->i_mutex);
@@ -2572,17 +2574,20 @@ static int vfs_rename_dir(struct inode *old_dir, struct dentry *old_dentry,
                 return error;
 
         target = new_dentry->d_inode;
-        if (target) {
+        if (target)
                 mutex_lock(&target->i_mutex);
-                dentry_unhash(new_dentry);
-        }
         if (d_mountpoint(old_dentry)||d_mountpoint(new_dentry))
                 error = -EBUSY;
-        else 
+        else {
+                if (target)
+                        dentry_unhash(new_dentry);
                 error = old_dir->i_op->rename(old_dir, old_dentry, new_dir, new_dentry);
+        }
         if (target) {
-                if (!error)
+                if (!error) {
                         target->i_flags |= S_DEAD;
+                        dont_mount(new_dentry);
+                }
                 mutex_unlock(&target->i_mutex);
                 if (d_unhashed(new_dentry))
                         d_rehash(new_dentry);
@@ -2614,7 +2619,7 @@ static int vfs_rename_other(struct inode *old_dir, struct dentry *old_dentry,
                 error = old_dir->i_op->rename(old_dir, old_dentry, new_dir, new_dentry);
         if (!error) {
                 if (target)
-                        target->i_flags |= S_DEAD;
+                        dont_mount(new_dentry);
                 if (!(old_dir->i_sb->s_type->fs_flags & FS_RENAME_DOES_D_MOVE))
                         d_move(old_dentry, new_dentry);
         }
diff --git a/fs/namespace.c b/fs/namespace.c
index 8174c8ab5c70..f20cb57d1067 100644
--- a/fs/namespace.c
+++ b/fs/namespace.c
@@ -1432,7 +1432,7 @@ static int graft_tree(struct vfsmount *mnt, struct path *path)
 
         err = -ENOENT;
         mutex_lock(&path->dentry->d_inode->i_mutex);
-        if (IS_DEADDIR(path->dentry->d_inode))
+        if (cant_mount(path->dentry))
                 goto out_unlock;
 
         err = security_sb_check_sb(mnt, path);
@@ -1623,7 +1623,7 @@ static int do_move_mount(struct path *path, char *old_name)
 
         err = -ENOENT;
         mutex_lock(&path->dentry->d_inode->i_mutex);
-        if (IS_DEADDIR(path->dentry->d_inode))
+        if (cant_mount(path->dentry))
                 goto out1;
 
         if (d_unlinked(path->dentry))
@@ -2234,7 +2234,7 @@ SYSCALL_DEFINE2(pivot_root, const char __user *, new_root,
         if (!check_mnt(root.mnt))
                 goto out2;
         error = -ENOENT;
-        if (IS_DEADDIR(new.dentry->d_inode))
+        if (cant_mount(old.dentry))
                 goto out2;
         if (d_unlinked(new.dentry))
                 goto out2;
diff --git a/include/linux/dcache.h b/include/linux/dcache.h
index 30b93b2a01a4..eebb617c17d8 100644
--- a/include/linux/dcache.h
+++ b/include/linux/dcache.h
@@ -186,6 +186,8 @@ d_iput:		no		no		no       yes
 
 #define DCACHE_FSNOTIFY_PARENT_WATCHED  0x0080 /* Parent inode is watched by some fsnotify listener */
 
+#define DCACHE_CANT_MOUNT       0x0100
+
 extern spinlock_t dcache_lock;
 extern seqlock_t rename_lock;
 
@@ -358,6 +360,18 @@ static inline int d_unlinked(struct dentry *dentry)
         return d_unhashed(dentry) && !IS_ROOT(dentry);
 }
 
+static inline int cant_mount(struct dentry *dentry)
+{
+        return (dentry->d_flags & DCACHE_CANT_MOUNT);
+}
+
+static inline void dont_mount(struct dentry *dentry)
+{
+        spin_lock(&dentry->d_lock);
+        dentry->d_flags |= DCACHE_CANT_MOUNT;
+        spin_unlock(&dentry->d_lock);
+}
+
 static inline struct dentry *dget_parent(struct dentry *dentry)
 {
         struct dentry *ret;