+struct Qdisc *qdisc_match_from_root(struct Qdisc *root, u32 handle)
+{
+ struct Qdisc *q;
+
+ if (!(root->flags & TCQ_F_BUILTIN) &&
+ root->handle == handle)
+ return root;
+
+ list_for_each_entry(q, &root->list, list) {
+ if (q->handle == handle)
+ return q;
+ }
+ return NULL;
+}
+
+/*
+ * This lock is needed until some qdiscs stop calling qdisc_tree_decrease_qlen()
+ * without rtnl_lock(); currently hfsc_dequeue(), netem_dequeue(), tbf_dequeue()
+ */
+static DEFINE_SPINLOCK(qdisc_list_lock);
+
+static void qdisc_list_add(struct Qdisc *q)
+{
+ if ((q->parent != TC_H_ROOT) && !(q->flags & TCQ_F_INGRESS)) {
+ spin_lock_bh(&qdisc_list_lock);
+ list_add_tail(&q->list, &qdisc_root_sleeping(q)->list);
+ spin_unlock_bh(&qdisc_list_lock);
+ }
+}
+
+void qdisc_list_del(struct Qdisc *q)
+{
+ if ((q->parent != TC_H_ROOT) && !(q->flags & TCQ_F_INGRESS)) {
+ spin_lock_bh(&qdisc_list_lock);
+ list_del(&q->list);
+ spin_unlock_bh(&qdisc_list_lock);
+ }
+}
+EXPORT_SYMBOL(qdisc_list_del);
+