3 files changed, 37 insertions, 6 deletions

diff --git a/fs/autofs4/expire.c b/fs/autofs4/expire.c
index 2f7951d67d16..cc1d01365905 100644
--- a/fs/autofs4/expire.c
+++ b/fs/autofs4/expire.c
@@ -295,7 +295,9 @@ struct dentry *autofs4_expire_direct(struct super_block *sb,
                 struct autofs_info *ino = autofs4_dentry_ino(root);
                 if (d_mountpoint(root)) {
                         ino->flags |= AUTOFS_INF_MOUNTPOINT;
-                        root->d_mounted--;
+                        spin_lock(&root->d_lock);
+                        root->d_flags &= ~DCACHE_MOUNTED;
+                        spin_unlock(&root->d_lock);
                 }
                 ino->flags |= AUTOFS_INF_EXPIRING;
                 init_completion(&ino->expire_complete);
@@ -503,7 +505,14 @@ int autofs4_do_expire_multi(struct super_block *sb, struct vfsmount *mnt,
 
                 spin_lock(&sbi->fs_lock);
                 if (ino->flags & AUTOFS_INF_MOUNTPOINT) {
-                        sb->s_root->d_mounted++;
+                        spin_lock(&sb->s_root->d_lock);
+                        /*
+                         * If we haven't been expired away, then reset
+                         * mounted status.
+                         */
+                        if (mnt->mnt_parent != mnt)
+                                sb->s_root->d_flags |= DCACHE_MOUNTED;
+                        spin_unlock(&sb->s_root->d_lock);
                         ino->flags &= ~AUTOFS_INF_MOUNTPOINT;
                 }
                 ino->flags &= ~AUTOFS_INF_EXPIRING;
diff --git a/fs/dcache.c b/fs/dcache.c
index 187fea040108..1d5cf511e1c7 100644
--- a/fs/dcache.c
+++ b/fs/dcache.c
@@ -1265,7 +1265,6 @@ struct dentry *d_alloc(struct dentry * parent, const struct qstr *name)
         dentry->d_sb = NULL;
         dentry->d_op = NULL;
         dentry->d_fsdata = NULL;
-        dentry->d_mounted = 0;
         INIT_HLIST_NODE(&dentry->d_hash);
         INIT_LIST_HEAD(&dentry->d_lru);
         INIT_LIST_HEAD(&dentry->d_subdirs);
diff --git a/fs/namespace.c b/fs/namespace.c
index 3dbfc072ec70..39a7d507fba0 100644
--- a/fs/namespace.c
+++ b/fs/namespace.c
@@ -492,6 +492,27 @@ static void __touch_mnt_namespace(struct mnt_namespace *ns)
 }
 
 /*
+ * Clear dentry's mounted state if it has no remaining mounts.
+ * vfsmount_lock must be held for write.
+ */
+static void dentry_reset_mounted(struct vfsmount *mnt, struct dentry *dentry)
+{
+        unsigned u;
+
+        for (u = 0; u < HASH_SIZE; u++) {
+                struct vfsmount *p;
+
+                list_for_each_entry(p, &mount_hashtable[u], mnt_hash) {
+                        if (p->mnt_mountpoint == dentry)
+                                return;
+                }
+        }
+        spin_lock(&dentry->d_lock);
+        dentry->d_flags &= ~DCACHE_MOUNTED;
+        spin_unlock(&dentry->d_lock);
+}
+
+/*
  * vfsmount lock must be held for write
  */
 static void detach_mnt(struct vfsmount *mnt, struct path *old_path)
@@ -502,7 +523,7 @@ static void detach_mnt(struct vfsmount *mnt, struct path *old_path)
         mnt->mnt_mountpoint = mnt->mnt_root;
         list_del_init(&mnt->mnt_child);
         list_del_init(&mnt->mnt_hash);
-        old_path->dentry->d_mounted--;
+        dentry_reset_mounted(old_path->mnt, old_path->dentry);
 }
 
 /*
@@ -513,7 +534,9 @@ void mnt_set_mountpoint(struct vfsmount *mnt, struct dentry *dentry,
 {
         child_mnt->mnt_parent = mntget(mnt);
         child_mnt->mnt_mountpoint = dget(dentry);
-        dentry->d_mounted++;
+        spin_lock(&dentry->d_lock);
+        dentry->d_flags |= DCACHE_MOUNTED;
+        spin_unlock(&dentry->d_lock);
 }
 
 /*
@@ -1073,7 +1096,7 @@ void umount_tree(struct vfsmount *mnt, int propagate, struct list_head *kill)
                 list_del_init(&p->mnt_child);
                 if (p->mnt_parent != p) {
                         p->mnt_parent->mnt_ghosts++;
-                        p->mnt_mountpoint->d_mounted--;
+                        dentry_reset_mounted(p->mnt_parent, p->mnt_mountpoint);
                 }
                 change_mnt_propagation(p, MS_PRIVATE);
         }