Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs-2.6

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs-2.6:
  [PATCH] mnt_expire is protected by namespace_sem, no need for vfsmount_lock
  [PATCH] do shrink_submounts() for all fs types
  [PATCH] sanitize locking in mark_mounts_for_expiry() and shrink_submounts()
  [PATCH] count ghost references to vfsmounts
  [PATCH] reduce stack footprint in namespace.c

8 files changed, 71 insertions, 146 deletions

diff --git a/fs/afs/internal.h b/fs/afs/internal.h
index 5ca3625cd39e..9ba16edc0af2 100644
--- a/fs/afs/internal.h
+++ b/fs/afs/internal.h
@@ -573,7 +573,6 @@ extern const struct file_operations afs_mntpt_file_operations;
 
 extern int afs_mntpt_check_symlink(struct afs_vnode *, struct key *);
 extern void afs_mntpt_kill_timer(void);
-extern void afs_umount_begin(struct vfsmount *, int);
 
 /*
  * proc.c
diff --git a/fs/afs/mntpt.c b/fs/afs/mntpt.c
index a3510b8ba3e7..2f5503902c37 100644
--- a/fs/afs/mntpt.c
+++ b/fs/afs/mntpt.c
@@ -283,11 +283,3 @@ void afs_mntpt_kill_timer(void)
         cancel_delayed_work(&afs_mntpt_expiry_timer);
         flush_scheduled_work();
 }
-
-/*
- * begin unmount by attempting to remove all automounted mountpoints we added
- */
-void afs_umount_begin(struct vfsmount *vfsmnt, int flags)
-{
-        shrink_submounts(vfsmnt, &afs_vfsmounts);
-}
diff --git a/fs/afs/super.c b/fs/afs/super.c
index 36bbce45f44b..4b572b801d8d 100644
--- a/fs/afs/super.c
+++ b/fs/afs/super.c
@@ -50,7 +50,6 @@ static const struct super_operations afs_super_ops = {
         .write_inode    = afs_write_inode,
         .destroy_inode  = afs_destroy_inode,
         .clear_inode    = afs_clear_inode,
-        .umount_begin   = afs_umount_begin,
         .put_super      = afs_put_super,
         .show_options   = generic_show_options,
 };
diff --git a/fs/cifs/cifs_dfs_ref.c b/fs/cifs/cifs_dfs_ref.c
index a1a95b027136..56c924033b78 100644
--- a/fs/cifs/cifs_dfs_ref.c
+++ b/fs/cifs/cifs_dfs_ref.c
@@ -33,7 +33,6 @@ void dfs_shrink_umount_helper(struct vfsmount *vfsmnt)
 {
         mark_mounts_for_expiry(&cifs_dfs_automount_list);
         mark_mounts_for_expiry(&cifs_dfs_automount_list);
-        shrink_submounts(vfsmnt, &cifs_dfs_automount_list);
 }
 
 /**
diff --git a/fs/namespace.c b/fs/namespace.c
index 7953c96a2071..94f026ec990a 100644
--- a/fs/namespace.c
+++ b/fs/namespace.c
@@ -155,15 +155,15 @@ static void __touch_mnt_namespace(struct mnt_namespace *ns)
         }
 }
 
-static void detach_mnt(struct vfsmount *mnt, struct nameidata *old_nd)
+static void detach_mnt(struct vfsmount *mnt, struct path *old_path)
 {
-        old_nd->path.dentry = mnt->mnt_mountpoint;
-        old_nd->path.mnt = mnt->mnt_parent;
+        old_path->dentry = mnt->mnt_mountpoint;
+        old_path->mnt = mnt->mnt_parent;
         mnt->mnt_parent = mnt;
         mnt->mnt_mountpoint = mnt->mnt_root;
         list_del_init(&mnt->mnt_child);
         list_del_init(&mnt->mnt_hash);
-        old_nd->path.dentry->d_mounted--;
+        old_path->dentry->d_mounted--;
 }
 
 void mnt_set_mountpoint(struct vfsmount *mnt, struct dentry *dentry,
@@ -174,12 +174,12 @@ void mnt_set_mountpoint(struct vfsmount *mnt, struct dentry *dentry,
         dentry->d_mounted++;
 }
 
-static void attach_mnt(struct vfsmount *mnt, struct nameidata *nd)
+static void attach_mnt(struct vfsmount *mnt, struct path *path)
 {
-        mnt_set_mountpoint(nd->path.mnt, nd->path.dentry, mnt);
+        mnt_set_mountpoint(path->mnt, path->dentry, mnt);
         list_add_tail(&mnt->mnt_hash, mount_hashtable +
-                        hash(nd->path.mnt, nd->path.dentry));
-        list_add_tail(&mnt->mnt_child, &nd->path.mnt->mnt_mounts);
+                        hash(path->mnt, path->dentry));
+        list_add_tail(&mnt->mnt_child, &path->mnt->mnt_mounts);
 }
 
 /*
@@ -262,10 +262,8 @@ static struct vfsmount *clone_mnt(struct vfsmount *old, struct dentry *root,
                 /* stick the duplicate mount on the same expiry list
                  * as the original if that was on one */
                 if (flag & CL_EXPIRE) {
-                        spin_lock(&vfsmount_lock);
                         if (!list_empty(&old->mnt_expire))
                                 list_add(&mnt->mnt_expire, &old->mnt_expire);
-                        spin_unlock(&vfsmount_lock);
                 }
         }
         return mnt;
@@ -548,6 +546,7 @@ void release_mounts(struct list_head *head)
                         m = mnt->mnt_parent;
                         mnt->mnt_mountpoint = mnt->mnt_root;
                         mnt->mnt_parent = mnt;
+                        m->mnt_ghosts--;
                         spin_unlock(&vfsmount_lock);
                         dput(dentry);
                         mntput(m);
@@ -572,12 +571,16 @@ void umount_tree(struct vfsmount *mnt, int propagate, struct list_head *kill)
                 __touch_mnt_namespace(p->mnt_ns);
                 p->mnt_ns = NULL;
                 list_del_init(&p->mnt_child);
-                if (p->mnt_parent != p)
+                if (p->mnt_parent != p) {
+                        p->mnt_parent->mnt_ghosts++;
                         p->mnt_mountpoint->d_mounted--;
+                }
                 change_mnt_propagation(p, MS_PRIVATE);
         }
 }
 
+static void shrink_submounts(struct vfsmount *mnt, struct list_head *umounts);
+
 static int do_umount(struct vfsmount *mnt, int flags)
 {
         struct super_block *sb = mnt->mnt_sb;
@@ -650,6 +653,9 @@ static int do_umount(struct vfsmount *mnt, int flags)
         spin_lock(&vfsmount_lock);
         event++;
 
+        if (!(flags & MNT_DETACH))
+                shrink_submounts(mnt, &umount_list);
+
         retval = -EBUSY;
         if (flags & MNT_DETACH || !propagate_mount_busy(mnt, 2)) {
                 if (!list_empty(&mnt->mnt_list))
@@ -744,7 +750,7 @@ struct vfsmount *copy_tree(struct vfsmount *mnt, struct dentry *dentry,
                                         int flag)
 {
         struct vfsmount *res, *p, *q, *r, *s;
-        struct nameidata nd;
+        struct path path;
 
         if (!(flag & CL_COPY_ALL) && IS_MNT_UNBINDABLE(mnt))
                 return NULL;
@@ -769,14 +775,14 @@ struct vfsmount *copy_tree(struct vfsmount *mnt, struct dentry *dentry,
                                 q = q->mnt_parent;
                         }
                         p = s;
-                        nd.path.mnt = q;
-                        nd.path.dentry = p->mnt_mountpoint;
+                        path.mnt = q;
+                        path.dentry = p->mnt_mountpoint;
                         q = clone_mnt(p, p->mnt_root, flag);
                         if (!q)
                                 goto Enomem;
                         spin_lock(&vfsmount_lock);
                         list_add_tail(&q->mnt_list, &res->mnt_list);