2 files changed, 34 insertions, 6 deletions

diff --git a/include/net/sch_generic.h b/include/net/sch_generic.h
index b37572db12ab..82086392735a 100644
--- a/include/net/sch_generic.h
+++ b/include/net/sch_generic.h
@@ -60,6 +60,7 @@ struct Qdisc_class_ops
         int                     (*graft)(struct Qdisc *, unsigned long cl,
                                         struct Qdisc *, struct Qdisc **);
         struct Qdisc *          (*leaf)(struct Qdisc *, unsigned long cl);
+        void                    (*qlen_notify)(struct Qdisc *, unsigned long);
 
         /* Class manipulation routines */
         unsigned long           (*get)(struct Qdisc *, u32 classid);
@@ -172,6 +173,7 @@ extern void dev_activate(struct net_device *dev);
 extern void dev_deactivate(struct net_device *dev);
 extern void qdisc_reset(struct Qdisc *qdisc);
 extern void qdisc_destroy(struct Qdisc *qdisc);
+extern void qdisc_tree_decrease_qlen(struct Qdisc *qdisc, unsigned int n);
 extern struct Qdisc *qdisc_alloc(struct net_device *dev, struct Qdisc_ops *ops);
 extern struct Qdisc *qdisc_create_dflt(struct net_device *dev,
                                        struct Qdisc_ops *ops, u32 parentid);
diff --git a/net/sched/sch_api.c b/net/sched/sch_api.c
index d99802f3023d..05a93da6f057 100644
--- a/net/sched/sch_api.c
+++ b/net/sched/sch_api.c
@@ -191,21 +191,27 @@ int unregister_qdisc(struct Qdisc_ops *qops)
    (root qdisc, all its children, children of children etc.)
  */
 
-struct Qdisc *qdisc_lookup(struct net_device *dev, u32 handle)
+static struct Qdisc *__qdisc_lookup(struct net_device *dev, u32 handle)
 {
         struct Qdisc *q;
 
-        read_lock(&qdisc_tree_lock);
         list_for_each_entry(q, &dev->qdisc_list, list) {
-                if (q->handle == handle) {
-                        read_unlock(&qdisc_tree_lock);
+                if (q->handle == handle)
                         return q;
-                }
         }
-        read_unlock(&qdisc_tree_lock);
         return NULL;
 }
 
+struct Qdisc *qdisc_lookup(struct net_device *dev, u32 handle)
+{
+        struct Qdisc *q;
+
+        read_lock(&qdisc_tree_lock);
+        q = __qdisc_lookup(dev, handle);
+        read_unlock(&qdisc_tree_lock);
+        return q;
+}
+
 static struct Qdisc *qdisc_leaf(struct Qdisc *p, u32 classid)
 {
         unsigned long cl;
@@ -348,6 +354,26 @@ dev_graft_qdisc(struct net_device *dev, struct Qdisc *qdisc)
         return oqdisc;
 }
 
+void qdisc_tree_decrease_qlen(struct Qdisc *sch, unsigned int n)
+{
+        struct Qdisc_class_ops *cops;
+        unsigned long cl;
+        u32 parentid;
+
+        if (n == 0)
+                return;
+        while ((parentid = sch->parent)) {
+                sch = __qdisc_lookup(sch->dev, TC_H_MAJ(parentid));
+                cops = sch->ops->cl_ops;
+                if (cops->qlen_notify) {
+                        cl = cops->get(sch, parentid);
+                        cops->qlen_notify(sch, cl);
+                        cops->put(sch, cl);
+                }
+                sch->q.qlen -= n;
+        }
+}
+EXPORT_SYMBOL(qdisc_tree_decrease_qlen);
 
 /* Graft qdisc "new" to class "classid" of qdisc "parent" or
    to device "dev".