security: remove dead hook sb_umount_busy

Unused hook.  Remove.

Signed-off-by: Eric Paris <eparis@redhat.com>
Signed-off-by: James Morris <jmorris@namei.org>
diff --git a/fs/namespace.c b/fs/namespace.c
index 8aea78c..6c9ca73 100644
--- a/fs/namespace.c
+++ b/fs/namespace.c
@@ -1116,8 +1116,6 @@
 		retval = 0;
 	}
 	spin_unlock(&vfsmount_lock);
-	if (retval)
-		security_sb_umount_busy(mnt);
 	up_write(&namespace_sem);
 	release_mounts(&umount_list);
 	return retval;
diff --git a/include/linux/security.h b/include/linux/security.h
index 354b0ce..b206795 100644
--- a/include/linux/security.h
+++ b/include/linux/security.h
@@ -272,12 +272,6 @@
  *	@mnt contains the mounted file system.
  *	@flags contains the unmount flags, e.g. MNT_FORCE.
  *	Return 0 if permission is granted.
- * @sb_umount_busy:
- *	Handle a failed umount of the @mnt mounted filesystem, e.g.  re-opening
- *	any files that were closed by umount_close.  This hook is called during
- *	an umount operation if the umount fails after a call to the
- *	umount_close hook.
- *	@mnt contains the mounted filesystem.
  * @sb_post_remount:
  *	Update the security module's state when a filesystem is remounted.
  *	This hook is only called if the remount was successful.
@@ -1474,7 +1468,6 @@
 	int (*sb_mount) (char *dev_name, struct path *path,
 			 char *type, unsigned long flags, void *data);
 	int (*sb_umount) (struct vfsmount *mnt, int flags);
-	void (*sb_umount_busy) (struct vfsmount *mnt);
 	void (*sb_post_remount) (struct vfsmount *mnt,
 				 unsigned long flags, void *data);
 	void (*sb_post_addmount) (struct vfsmount *mnt,
@@ -1771,7 +1764,6 @@
 int security_sb_mount(char *dev_name, struct path *path,
 		      char *type, unsigned long flags, void *data);
 int security_sb_umount(struct vfsmount *mnt, int flags);
-void security_sb_umount_busy(struct vfsmount *mnt);
 void security_sb_post_remount(struct vfsmount *mnt, unsigned long flags, void *data);
 void security_sb_post_addmount(struct vfsmount *mnt, struct path *mountpoint);
 int security_sb_pivotroot(struct path *old_path, struct path *new_path);
@@ -2089,9 +2081,6 @@
 	return 0;
 }
 
-static inline void security_sb_umount_busy(struct vfsmount *mnt)
-{ }
-
 static inline void security_sb_post_remount(struct vfsmount *mnt,
 					     unsigned long flags, void *data)
 { }
diff --git a/security/capability.c b/security/capability.c
index db72f4f..476d430 100644
--- a/security/capability.c
+++ b/security/capability.c
@@ -85,10 +85,6 @@
 	return 0;
 }
 
-static void cap_sb_umount_busy(struct vfsmount *mnt)
-{
-}
-
 static void cap_sb_post_remount(struct vfsmount *mnt, unsigned long flags,
 				void *data)
 {
@@ -933,7 +929,6 @@
 	set_to_cap_if_null(ops, sb_statfs);
 	set_to_cap_if_null(ops, sb_mount);
 	set_to_cap_if_null(ops, sb_umount);
-	set_to_cap_if_null(ops, sb_umount_busy);
 	set_to_cap_if_null(ops, sb_post_remount);
 	set_to_cap_if_null(ops, sb_post_addmount);
 	set_to_cap_if_null(ops, sb_pivotroot);
diff --git a/security/security.c b/security/security.c
index 591c25f..c1341fb 100644
--- a/security/security.c
+++ b/security/security.c
@@ -311,11 +311,6 @@
 	return security_ops->sb_umount(mnt, flags);
 }
 
-void security_sb_umount_busy(struct vfsmount *mnt)
-{
-	security_ops->sb_umount_busy(mnt);
-}
-
 void security_sb_post_remount(struct vfsmount *mnt, unsigned long flags, void *data)
 {
 	security_ops->sb_post_remount(mnt, flags, data);