namespace.c: get rid of mnt_ghosts

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

3 files changed, 9 insertions, 18 deletions

diff --git a/fs/mount.h b/fs/mount.h
index 64a858143ff9..3168dc41bad5 100644
--- a/fs/mount.h
+++ b/fs/mount.h
@@ -55,7 +55,7 @@ struct mount {
         int mnt_group_id;               /* peer group identifier */
         int mnt_expiry_mark;            /* true if marked for expiry */
         int mnt_pinned;
-        int mnt_ghosts;
+        struct path mnt_ex_mountpoint;
 };
 
 #define MNT_NS_INTERNAL ERR_PTR(-EINVAL) /* distinct from any mnt_namespace */
diff --git a/fs/namespace.c b/fs/namespace.c
index c8d214ce30c6..846ea43ab0c6 100644
--- a/fs/namespace.c
+++ b/fs/namespace.c
@@ -1136,20 +1136,8 @@ static void namespace_unlock(void)
         while (!list_empty(&head)) {
                 mnt = list_first_entry(&head, struct mount, mnt_hash);
                 list_del_init(&mnt->mnt_hash);
-                if (mnt_has_parent(mnt)) {
-                        struct dentry *dentry;
-                        struct mount *m;
-
-                        br_write_lock(&vfsmount_lock);
-                        dentry = mnt->mnt_mountpoint;
-                        m = mnt->mnt_parent;
-                        mnt->mnt_mountpoint = mnt->mnt.mnt_root;
-                        mnt->mnt_parent = mnt;
-                        m->mnt_ghosts--;
-                        br_write_unlock(&vfsmount_lock);
-                        dput(dentry);
-                        mntput(&m->mnt);
-                }
+                if (mnt->mnt_ex_mountpoint.mnt)
+                        path_put(&mnt->mnt_ex_mountpoint);
                 mntput(&mnt->mnt);
         }
 }
@@ -1181,8 +1169,12 @@ void umount_tree(struct mount *mnt, int propagate)
                 p->mnt_ns = NULL;
                 list_del_init(&p->mnt_child);
                 if (mnt_has_parent(p)) {
-                        p->mnt_parent->mnt_ghosts++;
                         put_mountpoint(p->mnt_mp);
+                        /* move the reference to mountpoint into ->mnt_ex_mountpoint */
+                        p->mnt_ex_mountpoint.dentry = p->mnt_mountpoint;
+                        p->mnt_ex_mountpoint.mnt = &p->mnt_parent->mnt;
+                        p->mnt_mountpoint = p->mnt.mnt_root;
+                        p->mnt_parent = p;
                         p->mnt_mp = NULL;
                 }
                 change_mnt_propagation(p, MS_PRIVATE);
diff --git a/fs/pnode.c b/fs/pnode.c
index 9af0df15256e..3cfd48cf887e 100644
--- a/fs/pnode.c
+++ b/fs/pnode.c
@@ -278,8 +278,7 @@ out:
  */
 static inline int do_refcount_check(struct mount *mnt, int count)
 {
-        int mycount = mnt_get_count(mnt) - mnt->mnt_ghosts;
-        return (mycount > count);
+        return mnt_get_count(mnt) > count;
 }
 
 /*