1 files changed, 45 insertions, 43 deletions

diff --git a/net/sched/sch_taprio.c b/net/sched/sch_taprio.c
index 5c91df52b8c2..66fe2b82af9a 100644
--- a/net/sched/sch_taprio.c
+++ b/net/sched/sch_taprio.c
@@ -114,9 +114,6 @@ static void taprio_free_sched_cb(struct rcu_head *head)
 	struct sched_gate_list *sched = container_of(head, struct sched_gate_list, rcu);
 	struct sched_entry *entry, *n;
 
-	if (!sched)
-		return;
-
 	list_for_each_entry_safe(entry, n, &sched->entries, list) {
 		list_del(&entry->list);
 		kfree(entry);
@@ -438,6 +435,11 @@ static int taprio_enqueue(struct sk_buff *skb, struct Qdisc *sch,
 	struct Qdisc *child;
 	int queue;
 
+	if (unlikely(FULL_OFFLOAD_IS_ENABLED(q->flags))) {
+		WARN_ONCE(1, "Trying to enqueue skb into the root of a taprio qdisc configured with full offload\n");
+		return qdisc_drop(skb, sch, to_free);
+	}
+
 	queue = skb_get_queue_mapping(skb);
 
 	child = q->qdiscs[queue];
@@ -529,23 +531,7 @@ static struct sk_buff *taprio_peek_soft(struct Qdisc *sch)
 
 static struct sk_buff *taprio_peek_offload(struct Qdisc *sch)
 {
-	struct taprio_sched *q = qdisc_priv(sch);
-	struct net_device *dev = qdisc_dev(sch);
-	struct sk_buff *skb;
-	int i;
-
-	for (i = 0; i < dev->num_tx_queues; i++) {
-		struct Qdisc *child = q->qdiscs[i];
-
-		if (unlikely(!child))
-			continue;
-
-		skb = child->ops->peek(child);
-		if (!skb)
-			continue;
-
-		return skb;
-	}
+	WARN_ONCE(1, "Trying to peek into the root of a taprio qdisc configured with full offload\n");
 
 	return NULL;
 }
@@ -654,27 +640,7 @@ done:
 
 static struct sk_buff *taprio_dequeue_offload(struct Qdisc *sch)
 {
-	struct taprio_sched *q = qdisc_priv(sch);
-	struct net_device *dev = qdisc_dev(sch);
-	struct sk_buff *skb;
-	int i;
-
-	for (i = 0; i < dev->num_tx_queues; i++) {
-		struct Qdisc *child = q->qdiscs[i];
-
-		if (unlikely(!child))
-			continue;
-
-		skb = child->ops->dequeue(child);
-		if (unlikely(!skb))
-			continue;
-
-		qdisc_bstats_update(sch, skb);
-		qdisc_qstats_backlog_dec(sch, skb);
-		sch->q.qlen--;
-
-		return skb;
-	}
+	WARN_ONCE(1, "Trying to dequeue from the root of a taprio qdisc configured with full offload\n");
 
 	return NULL;
 }
@@ -1759,6 +1725,37 @@ static int taprio_init(struct Qdisc *sch, struct nlattr *opt,
 	return taprio_change(sch, opt, extack);
 }
 
+static void taprio_attach(struct Qdisc *sch)
+{
+	struct taprio_sched *q = qdisc_priv(sch);
+	struct net_device *dev = qdisc_dev(sch);
+	unsigned int ntx;
+
+	/* Attach underlying qdisc */
+	for (ntx = 0; ntx < dev->num_tx_queues; ntx++) {
+		struct Qdisc *qdisc = q->qdiscs[ntx];
+		struct Qdisc *old;
+
+		if (FULL_OFFLOAD_IS_ENABLED(q->flags)) {
+			qdisc->flags |= TCQ_F_ONETXQUEUE | TCQ_F_NOPARENT;
+			old = dev_graft_qdisc(qdisc->dev_queue, qdisc);
+			if (ntx < dev->real_num_tx_queues)
+				qdisc_hash_add(qdisc, false);
+		} else {
+			old = dev_graft_qdisc(qdisc->dev_queue, sch);
+			qdisc_refcount_inc(sch);
+		}
+		if (old)
+			qdisc_put(old);
+	}
+
+	/* access to the child qdiscs is not needed in offload mode */
+	if (FULL_OFFLOAD_IS_ENABLED(q->flags)) {
+		kfree(q->qdiscs);
+		q->qdiscs = NULL;
+	}
+}
+
 static struct netdev_queue *taprio_queue_get(struct Qdisc *sch,
 					     unsigned long cl)
 {
@@ -1785,8 +1782,12 @@ static int taprio_graft(struct Qdisc *sch, unsigned long cl,
 	if (dev->flags & IFF_UP)
 		dev_deactivate(dev);
 
-	*old = q->qdiscs[cl - 1];
-	q->qdiscs[cl - 1] = new;
+	if (FULL_OFFLOAD_IS_ENABLED(q->flags)) {
+		*old = dev_graft_qdisc(dev_queue, new);
+	} else {
+		*old = q->qdiscs[cl - 1];
+		q->qdiscs[cl - 1] = new;
+	}
 
 	if (new)
 		new->flags |= TCQ_F_ONETXQUEUE | TCQ_F_NOPARENT;
@@ -2020,6 +2021,7 @@ static struct Qdisc_ops taprio_qdisc_ops __read_mostly = {
 	.change		= taprio_change,
 	.destroy	= taprio_destroy,
 	.reset		= taprio_reset,
+	.attach		= taprio_attach,
 	.peek		= taprio_peek,
 	.dequeue	= taprio_dequeue,
 	.enqueue	= taprio_enqueue,