1 files changed, 835 insertions, 0 deletions

diff --git a/net/sched/sch_ets.c b/net/sched/sch_ets.c
new file mode 100644
index 000000000..05817c556
--- /dev/null
+++ b/net/sched/sch_ets.c
@@ -0,0 +1,835 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * net/sched/sch_ets.c         Enhanced Transmission Selection scheduler
+ *
+ * Description
+ * -----------
+ *
+ * The Enhanced Transmission Selection scheduler is a classful queuing
+ * discipline that merges functionality of PRIO and DRR qdiscs in one scheduler.
+ * ETS makes it easy to configure a set of strict and bandwidth-sharing bands to
+ * implement the transmission selection described in 802.1Qaz.
+ *
+ * Although ETS is technically classful, it's not possible to add and remove
+ * classes at will. Instead one specifies number of classes, how many are
+ * PRIO-like and how many DRR-like, and quanta for the latter.
+ *
+ * Algorithm
+ * ---------
+ *
+ * The strict classes, if any, are tried for traffic first: first band 0, if it
+ * has no traffic then band 1, etc.
+ *
+ * When there is no traffic in any of the strict queues, the bandwidth-sharing
+ * ones are tried next. Each band is assigned a deficit counter, initialized to
+ * "quantum" of that band. ETS maintains a list of active bandwidth-sharing
+ * bands whose qdiscs are non-empty. A packet is dequeued from the band at the
+ * head of the list if the packet size is smaller or equal to the deficit
+ * counter. If the counter is too small, it is increased by "quantum" and the
+ * scheduler moves on to the next band in the active list.
+ */
+
+#include <linux/module.h>
+#include <net/gen_stats.h>
+#include <net/netlink.h>
+#include <net/pkt_cls.h>
+#include <net/pkt_sched.h>
+#include <net/sch_generic.h>
+
+struct ets_class {
+	struct list_head alist; /* In struct ets_sched.active. */
+	struct Qdisc *qdisc;
+	u32 quantum;
+	u32 deficit;
+	struct gnet_stats_basic_packed bstats;
+	struct gnet_stats_queue qstats;
+};
+
+struct ets_sched {
+	struct list_head active;
+	struct tcf_proto __rcu *filter_list;
+	struct tcf_block *block;
+	unsigned int nbands;
+	unsigned int nstrict;
+	u8 prio2band[TC_PRIO_MAX + 1];
+	struct ets_class classes[TCQ_ETS_MAX_BANDS];
+};
+
+static const struct nla_policy ets_policy[TCA_ETS_MAX + 1] = {
+	[TCA_ETS_NBANDS] = { .type = NLA_U8 },
+	[TCA_ETS_NSTRICT] = { .type = NLA_U8 },
+	[TCA_ETS_QUANTA] = { .type = NLA_NESTED },
+	[TCA_ETS_PRIOMAP] = { .type = NLA_NESTED },
+};
+
+static const struct nla_policy ets_priomap_policy[TCA_ETS_MAX + 1] = {
+	[TCA_ETS_PRIOMAP_BAND] = { .type = NLA_U8 },
+};
+
+static const struct nla_policy ets_quanta_policy[TCA_ETS_MAX + 1] = {
+	[TCA_ETS_QUANTA_BAND] = { .type = NLA_U32 },
+};
+
+static const struct nla_policy ets_class_policy[TCA_ETS_MAX + 1] = {
+	[TCA_ETS_QUANTA_BAND] = { .type = NLA_U32 },
+};
+
+static int ets_quantum_parse(struct Qdisc *sch, const struct nlattr *attr,
+			     unsigned int *quantum,
+			     struct netlink_ext_ack *extack)
+{
+	*quantum = nla_get_u32(attr);
+	if (!*quantum) {
+		NL_SET_ERR_MSG(extack, "ETS quantum cannot be zero");
+		return -EINVAL;
+	}
+	return 0;
+}
+
+static struct ets_class *
+ets_class_from_arg(struct Qdisc *sch, unsigned long arg)
+{
+	struct ets_sched *q = qdisc_priv(sch);
+
+	return &q->classes[arg - 1];
+}
+
+static u32 ets_class_id(struct Qdisc *sch, const struct ets_class *cl)
+{
+	struct ets_sched *q = qdisc_priv(sch);
+	int band = cl - q->classes;
+
+	return TC_H_MAKE(sch->handle, band + 1);
+}
+
+static void ets_offload_change(struct Qdisc *sch)
+{
+	struct net_device *dev = qdisc_dev(sch);
+	struct ets_sched *q = qdisc_priv(sch);
+	struct tc_ets_qopt_offload qopt;
+	unsigned int w_psum_prev = 0;
+	unsigned int q_psum = 0;
+	unsigned int q_sum = 0;
+	unsigned int quantum;
+	unsigned int w_psum;
+	unsigned int weight;
+	unsigned int i;
+
+	if (!tc_can_offload(dev) || !dev->netdev_ops->ndo_setup_tc)
+		return;
+
+	qopt.command = TC_ETS_REPLACE;
+	qopt.handle = sch->handle;
+	qopt.parent = sch->parent;
+	qopt.replace_params.bands = q->nbands;
+	qopt.replace_params.qstats = &sch->qstats;
+	memcpy(&qopt.replace_params.priomap,
+	       q->prio2band, sizeof(q->prio2band));
+
+	for (i = 0; i < q->nbands; i++)
+		q_sum += q->classes[i].quantum;
+
+	for (i = 0; i < q->nbands; i++) {
+		quantum = q->classes[i].quantum;
+		q_psum += quantum;
+		w_psum = quantum ? q_psum * 100 / q_sum : 0;
+		weight = w_psum - w_psum_prev;
+		w_psum_prev = w_psum;
+
+		qopt.replace_params.quanta[i] = quantum;
+		qopt.replace_params.weights[i] = weight;
+	}
+
+	dev->netdev_ops->ndo_setup_tc(dev, TC_SETUP_QDISC_ETS, &qopt);
+}
+
+static void ets_offload_destroy(struct Qdisc *sch)
+{
+	struct net_device *dev = qdisc_dev(sch);
+	struct tc_ets_qopt_offload qopt;
+
+	if (!tc_can_offload(dev) || !dev->netdev_ops->ndo_setup_tc)
+		return;
+
+	qopt.command = TC_ETS_DESTROY;
+	qopt.handle = sch->handle;
+	qopt.parent = sch->parent;
+	dev->netdev_ops->ndo_setup_tc(dev, TC_SETUP_QDISC_ETS, &qopt);
+}
+
+static void ets_offload_graft(struct Qdisc *sch, struct Qdisc *new,
+			      struct Qdisc *old, unsigned long arg,
+			      struct netlink_ext_ack *extack)
+{
+	struct net_device *dev = qdisc_dev(sch);
+	struct tc_ets_qopt_offload qopt;
+
+	qopt.command = TC_ETS_GRAFT;
+	qopt.handle = sch->handle;
+	qopt.parent = sch->parent;
+	qopt.graft_params.band = arg - 1;
+	qopt.graft_params.child_handle = new->handle;
+
+	qdisc_offload_graft_helper(dev, sch, new, old, TC_SETUP_QDISC_ETS,
+				   &qopt, extack);
+}
+
+static int ets_offload_dump(struct Qdisc *sch)
+{
+	struct tc_ets_qopt_offload qopt;
+
+	qopt.command = TC_ETS_STATS;
+	qopt.handle = sch->handle;
+	qopt.parent = sch->parent;
+	qopt.stats.bstats = &sch->bstats;
+	qopt.stats.qstats = &sch->qstats;
+
+	return qdisc_offload_dump_helper(sch, TC_SETUP_QDISC_ETS, &qopt);
+}
+
+static bool ets_class_is_strict(struct ets_sched *q, const struct ets_class *cl)
+{
+	unsigned int band = cl - q->classes;
+
+	return band < q->nstrict;
+}
+
+static int ets_class_change(struct Qdisc *sch, u32 classid, u32 parentid,
+			    struct nlattr **tca, unsigned long *arg,
+			    struct netlink_ext_ack *extack)
+{
+	struct ets_class *cl = ets_class_from_arg(sch, *arg);
+	struct ets_sched *q = qdisc_priv(sch);
+	struct nlattr *opt = tca[TCA_OPTIONS];
+	struct nlattr *tb[TCA_ETS_MAX + 1];
+	unsigned int quantum;
+	int err;
+
+	/* Classes can be added and removed only through Qdisc_ops.change
+	 * interface.
+	 */
+	if (!cl) {
+		NL_SET_ERR_MSG(extack, "Fine-grained class addition and removal is not supported");
+		return -EOPNOTSUPP;
+	}
+
+	if (!opt) {
+		NL_SET_ERR_MSG(extack, "ETS options are required for this operation");
+		return -EINVAL;
+	}
+
+	err = nla_parse_nested(tb, TCA_ETS_MAX, opt, ets_class_policy, extack);
+	if (err < 0)
+		return err;
+
+	if (!tb[TCA_ETS_QUANTA_BAND])
+		/* Nothing to configure. */
+		return 0;
+
+	if (ets_class_is_strict(q, cl)) {
+		NL_SET_ERR_MSG(extack, "Strict bands do not have a configurable quantum");
+		return -EINVAL;
+	}
+
+	err = ets_quantum_parse(sch, tb[TCA_ETS_QUANTA_BAND], &quantum,
+				extack);
+	if (err)
+		return err;
+
+	sch_tree_lock(sch);
+	cl->quantum = quantum;
+	sch_tree_unlock(sch);
+
+	ets_offload_change(sch);
+	return 0;
+}
+
+static int ets_class_graft(struct Qdisc *sch, unsigned long arg,
+			   struct Qdisc *new, struct Qdisc **old,
+			   struct netlink_ext_ack *extack)
+{
+	struct ets_class *cl = ets_class_from_arg(sch, arg);
+
+	if (!new) {
+		new = qdisc_create_dflt(sch->dev_queue, &pfifo_qdisc_ops,
+					ets_class_id(sch, cl), NULL);
+		if (!new)
+			new = &noop_qdisc;
+		else
+			qdisc_hash_add(new, true);
+	}
+
+	*old = qdisc_replace(sch, new, &cl->qdisc);
+	ets_offload_graft(sch, new, *old, arg, extack);
+	return 0;
+}
+
+static struct Qdisc *ets_class_leaf(struct Qdisc *sch, unsigned long arg)
+{
+	struct ets_class *cl = ets_class_from_arg(sch, arg);
+
+	return cl->qdisc;
+}
+
+static unsigned long ets_class_find(struct Qdisc *sch, u32 classid)
+{
+	unsigned long band = TC_H_MIN(classid);
+	struct ets_sched *q = qdisc_priv(sch);
+
+	if (band - 1 >= q->nbands)
+		return 0;
+	return band;
+}
+
+static void ets_class_qlen_notify(struct Qdisc *sch, unsigned long arg)
+{
+	struct ets_class *cl = ets_class_from_arg(sch, arg);
+	struct ets_sched *q = qdisc_priv(sch);
+
+	/* We get notified about zero-length child Qdiscs as well if they are
+	 * offloaded. Those aren't on the active list though, so don't attempt
+	 * to remove them.
+	 */
+	if (!ets_class_is_strict(q, cl) && sch->q.qlen)
+		list_del(&cl->alist);
+}
+
+static int ets_class_dump(struct Qdisc *sch, unsigned long arg,
+			  struct sk_buff *skb, struct tcmsg *tcm)
+{
+	struct ets_class *cl = ets_class_from_arg(sch, arg);
+	struct ets_sched *q = qdisc_priv(sch);
+	struct nlattr *nest;
+
+	tcm->tcm_parent = TC_H_ROOT;
+	tcm->tcm_handle = ets_class_id(sch, cl);
+	tcm->tcm_info = cl->qdisc->handle;
+
+	nest = nla_nest_start_noflag(skb, TCA_OPTIONS);
+	if (!nest)
+		goto nla_put_failure;
+	if (!ets_class_is_strict(q, cl)) {
+		if (nla_put_u32(skb, TCA_ETS_QUANTA_BAND, cl->quantum))
+			goto nla_put_failure;
+	}
+	return nla_nest_end(skb, nest);
+
+nla_put_failure:
+	nla_nest_cancel(skb, nest);
+	return -EMSGSIZE;
+}
+
+static int ets_class_dump_stats(struct Qdisc *sch, unsigned long arg,
+				struct gnet_dump *d)
+{
+	struct ets_class *cl = ets_class_from_arg(sch, arg);
+	struct Qdisc *cl_q = cl->qdisc;
+
+	if (gnet_stats_copy_basic(qdisc_root_sleeping_running(sch),
+				  d, NULL, &cl_q->bstats) < 0 ||
+	    qdisc_qstats_copy(d, cl_q) < 0)
+		return -1;
+
+	return 0;
+}
+
+static void ets_qdisc_walk(struct Qdisc *sch, struct qdisc_walker *arg)
+{
+	struct ets_sched *q = qdisc_priv(sch);
+	int i;
+
+	if (arg->stop)
+		return;
+
+	for (i = 0; i < q->nbands; i++) {
+		if (arg->count < arg->skip) {
+			arg->count++;
+			continue;
+		}
+		if (arg->fn(sch, i + 1, arg) < 0) {
+			arg->stop = 1;
+			break;
+		}
+		arg->count++;
+	}
+}
+
+static struct tcf_block *
+ets_qdisc_tcf_block(struct Qdisc *sch, unsigned long cl,
+		    struct netlink_ext_ack *extack)
+{
+	struct ets_sched *q = qdisc_priv(sch);
+
+	if (cl) {
+		NL_SET_ERR_MSG(extack, "ETS classid must be zero");
+		return NULL;
+	}
+
+	return q->block;
+}
+
+static unsigned long ets_qdisc_bind_tcf(struct Qdisc *sch, unsigned long parent,
+					u32 classid)
+{
+	return ets_class_find(sch, classid);
+}
+
+static void ets_qdisc_unbind_tcf(struct Qdisc *sch, unsigned long arg)
+{
+}
+
+static struct ets_class *ets_classify(struct sk_buff *skb, struct Qdisc *sch,
+				      int *qerr)
+{
+	struct ets_sched *q = qdisc_priv(sch);
+	u32 band = skb->priority;
+	struct tcf_result res;
+	struct tcf_proto *fl;
+	int err;
+
+	*qerr = NET_XMIT_SUCCESS | __NET_XMIT_BYPASS;
+	if (TC_H_MAJ(skb->priority) != sch->handle) {
+		fl = rcu_dereference_bh(q->filter_list);
+		err = tcf_classify(skb, fl, &res, false);
+#ifdef CONFIG_NET_CLS_ACT
+		switch (err) {
+		case TC_ACT_STOLEN:
+		case TC_ACT_QUEUED:
+		case TC_ACT_TRAP:
+			*qerr = NET_XMIT_SUCCESS | __NET_XMIT_STOLEN;
+			fallthrough;
+		case TC_ACT_SHOT:
+			return NULL;
+		}
+#endif
+		if (!fl || err < 0) {
+			if (TC_H_MAJ(band))
+				band = 0;
+			return &q->classes[q->prio2band[band & TC_PRIO_MAX]];
+		}
+		band = res.classid;
+	}
+	band = TC_H_MIN(band) - 1;
+	if (band >= q->nbands)
+		return &q->classes[q->prio2band[0]];
+	return &q->classes[band];
+}
+
+static int ets_qdisc_enqueue(struct sk_buff *skb, struct Qdisc *sch,
+			     struct sk_buff **to_free)
+{
+	unsigned int len = qdisc_pkt_len(skb);
+	struct ets_sched *q = qdisc_priv(sch);
+	struct ets_class *cl;
+	int err = 0;
+	bool first;
+
+	cl = ets_classify(skb, sch, &err);
+	if (!cl) {
+		if (err & __NET_XMIT_BYPASS)
+			qdisc_qstats_drop(sch);
+		__qdisc_drop(skb, to_free);
+		return err;
+	}
+
+	first = !cl->qdisc->q.qlen;
+	err = qdisc_enqueue(skb, cl->qdisc, to_free);
+	if (unlikely(err != NET_XMIT_SUCCESS)) {
+		if (net_xmit_drop_count(err)) {
+			cl->qstats.drops++;
+			qdisc_qstats_drop(sch);
+		}
+		return err;
+	}
+
+	if (first && !ets_class_is_strict(q, cl)) {
+		list_add_tail(&cl->alist, &q->active);
+		cl->deficit = cl->quantum;
+	}
+
+	sch->qstats.backlog += len;
+	sch->q.qlen++;
+	return err;
+}
+
+static struct sk_buff *
+ets_qdisc_dequeue_skb(struct Qdisc *sch, struct sk_buff *skb)
+{
+	qdisc_bstats_update(sch, skb);
+	qdisc_qstats_backlog_dec(sch, skb);
+	sch->q.qlen--;
+	return skb;
+}
+
+static struct sk_buff *ets_qdisc_dequeue(struct Qdisc *sch)
+{
+	struct ets_sched *q = qdisc_priv(sch);
+	struct ets_class *cl;
+	struct sk_buff *skb;
+	unsigned int band;
+	unsigned int len;
+
+	while (1) {
+		for (band = 0; band < q->nstrict; band++) {
+			cl = &q->classes[band];
+			skb = qdisc_dequeue_peeked(cl->qdisc);
+			if (skb)
+				return ets_qdisc_dequeue_skb(sch, skb);
+		}
+
+		if (list_empty(&q->active))
+			goto out;
+
+		cl = list_first_entry(&q->active, struct ets_class, alist);
+		skb = cl->qdisc->ops->peek(cl->qdisc);
+		if (!skb) {
+			qdisc_warn_nonwc(__func__, cl->qdisc);
+			goto out;
+		}
+
+		len = qdisc_pkt_len(skb);
+		if (len <= cl->deficit) {
+			cl->deficit -= len;
+			skb = qdisc_dequeue_peeked(cl->qdisc);
+			if (unlikely(!skb))
+				goto out;
+			if (cl->qdisc->q.qlen == 0)
+				list_del(&cl->alist);
+			return ets_qdisc_dequeue_skb(sch, skb);
+		}
+
+		cl->deficit += cl->quantum;
+		list_move_tail(&cl->alist, &q->active);
+	}
+out:
+	return NULL;
+}
+
+static int ets_qdisc_priomap_parse(struct nlattr *priomap_attr,
+				   unsigned int nbands, u8 *priomap,
+				   struct netlink_ext_ack *extack)
+{
+	const struct nlattr *attr;
+	int prio = 0;
+	u8 band;
+	int rem;
+	int err;
+
+	err = __nla_validate_nested(priomap_attr, TCA_ETS_MAX,
+				    ets_priomap_policy, NL_VALIDATE_STRICT,
+				    extack);
+	if (err)
+		return err;
+
+	nla_for_each_nested(attr, priomap_attr, rem) {
+		switch (nla_type(attr)) {
+		case TCA_ETS_PRIOMAP_BAND:
+			if (prio > TC_PRIO_MAX) {
+				NL_SET_ERR_MSG_MOD(extack, "Too many priorities in ETS priomap");
+				return -EINVAL;
+			}
+			band = nla_get_u8(attr);
+			if (band >= nbands) {
+				NL_SET_ERR_MSG_MOD(extack, "Invalid band number in ETS priomap");
+				return -EINVAL;
+			}
+			priomap[prio++] = band;
+			break;
+		default:
+			WARN_ON_ONCE(1); /* Validate should have caught this. */
+			return -EINVAL;
+		}
+	}
+
+	return 0;
+}
+
+static int ets_qdisc_quanta_parse(struct Qdisc *sch, struct nlattr *quanta_attr,
+				  unsigned int nbands, unsigned int nstrict,
+				  unsigned int *quanta,
+				  struct netlink_ext_ack *extack)
+{
+	const struct nlattr *attr;
+	int band = nstrict;
+	int rem;
+	int err;
+
+	err = __nla_validate_nested(quanta_attr, TCA_ETS_MAX,
+				    ets_quanta_policy, NL_VALIDATE_STRICT,
+				    extack);
+	if (err < 0)
+		return err;
+
+	nla_for_each_nested(attr, quanta_attr, rem) {
+		switch (nla_type(attr)) {
+		case TCA_ETS_QUANTA_BAND:
+			if (band >= nbands) {
+				NL_SET_ERR_MSG_MOD(extack, "ETS quanta has more values than bands");
+				return -EINVAL;
+			}
+			err = ets_quantum_parse(sch, attr, &quanta[band++],
+						extack);
+			if (err)
+				return err;
+			break;
+		default:
+			WARN_ON_ONCE(1); /* Validate should have caught this. */
+			return -EINVAL;
+		}
+	}
+
+	return 0;
+}
+
+static int ets_qdisc_change(struct Qdisc *sch, struct nlattr *opt,
+			    struct netlink_ext_ack *extack)
+{
+	unsigned int quanta[TCQ_ETS_MAX_BANDS] = {0};
+	struct Qdisc *queues[TCQ_ETS_MAX_BANDS];
+	struct ets_sched *q = qdisc_priv(sch);
+	struct nlattr *tb[TCA_ETS_MAX + 1];
+	unsigned int oldbands = q->nbands;
+	u8 priomap[TC_PRIO_MAX + 1];
+	unsigned int nstrict = 0;
+	unsigned int nbands;
+	unsigned int i;
+	int err;
+
+	if (!opt) {
+		NL_SET_ERR_MSG(extack, "ETS options are required for this operation");
+		return -EINVAL;
+	}
+
+	err = nla_parse_nested(tb, TCA_ETS_MAX, opt, ets_policy, extack);
+	if (err < 0)
+		return err;
+
+	if (!tb[TCA_ETS_NBANDS]) {
+		NL_SET_ERR_MSG_MOD(extack, "Number of bands is a required argument");
+		return -EINVAL;
+	}
+	nbands = nla_get_u8(tb[TCA_ETS_NBANDS]);
+	if (nbands < 1 || nbands > TCQ_ETS_MAX_BANDS) {
+		NL_SET_ERR_MSG_MOD(extack, "Invalid number of bands");
+		return -EINVAL;
+	}
+	/* Unless overridden, traffic goes to the last band. */
+	memset(priomap, nbands - 1, sizeof(priomap));
+
+	if (tb[TCA_ETS_NSTRICT]) {
+		nstrict = nla_get_u8(tb[TCA_ETS_NSTRICT]);
+		if (nstrict > nbands) {
+			NL_SET_ERR_MSG_MOD(extack, "Invalid number of strict bands");
+			return -EINVAL;
+		}
+	}
+
+	if (tb[TCA_ETS_PRIOMAP]) {
+		err = ets_qdisc_priomap_parse(tb[TCA_ETS_PRIOMAP],
+					      nbands, priomap, extack);
+		if (err)
+			return err;
+	}
+
+	if (tb[TCA_ETS_QUANTA]) {
+		err = ets_qdisc_quanta_parse(sch, tb[TCA_ETS_QUANTA],
+					     nbands, nstrict, quanta, extack);
+		if (err)
+			return err;
+	}
+	/* If there are more bands than strict + quanta provided, the remaining
+	 * ones are ETS with quantum of MTU. Initialize the missing values here.
+	 */
+	for (i = nstrict; i < nbands; i++) {
+		if (!quanta[i])
+			quanta[i] = psched_mtu(qdisc_dev(sch));
+	}
+
+	/* Before commit, make sure we can allocate all new qdiscs */
+	for (i = oldbands; i < nbands; i++) {
+		queues[i] = qdisc_create_dflt(sch->dev_queue, &pfifo_qdisc_ops,
+					      ets_class_id(sch, &q->classes[i]),
+					      extack);
+		if (!queues[i]) {
+			while (i > oldbands)
+				qdisc_put(queues[--i]);
+			return -ENOMEM;
+		}
+	}
+
+	sch_tree_lock(sch);
+
+	q->nbands = nbands;
+	for (i = nstrict; i < q->nstrict; i++) {
+		INIT_LIST_HEAD(&q->classes[i].alist);
+		if (q->classes[i].qdisc->q.qlen) {
+			list_add_tail(&q->classes[i].alist, &q->active);
+			q->classes[i].deficit = quanta[i];
+		}
+	}
+	for (i = q->nbands; i < oldbands; i++) {
+		if (i >= q->nstrict && q->classes[i].qdisc->q.qlen)
+			list_del(&q->classes[i].alist);
+		qdisc_tree_flush_backlog(q->classes[i].qdisc);
+	}
+	q->nstrict = nstrict;
+	memcpy(q->prio2band, priomap, sizeof(priomap));
+
+	for (i = 0; i < q->nbands; i++)
+		q->classes[i].quantum = quanta[i];
+
+	for (i = oldbands; i < q->nbands; i++) {
+		q->classes[i].qdisc = queues[i];
+		if (q->classes[i].qdisc != &noop_qdisc)
+			qdisc_hash_add(q->classes[i].qdisc, true);
+	}
+
+	sch_tree_unlock(sch);
+
+	ets_offload_change(sch);
+	for (i = q->nbands; i < oldbands; i++) {
+		qdisc_put(q->classes[i].qdisc);
+		memset(&q->classes[i], 0, sizeof(q->classes[i]));
+	}
+	return 0;
+}
+
+static int ets_qdisc_init(struct Qdisc *sch, struct nlattr *opt,
+			  struct netlink_ext_ack *extack)
+{
+	struct ets_sched *q = qdisc_priv(sch);
+	int err;
+
+	if (!opt)
+		return -EINVAL;
+
+	err = tcf_block_get(&q->block, &q->filter_list, sch, extack);
+	if (err)
+		return err;
+
+	INIT_LIST_HEAD(&q->active);
+	return ets_qdisc_change(sch, opt, extack);
+}
+
+static void ets_qdisc_reset(struct Qdisc *sch)
+{
+	struct ets_sched *q = qdisc_priv(sch);
+	int band;
+
+	for (band = q->nstrict; band < q->nbands; band++) {
+		if (q->classes[band].qdisc->q.qlen)
+			list_del(&q->classes[band].alist);
+	}
+	for (band = 0; band < q->nbands; band++)
+		qdisc_reset(q->classes[band].qdisc);
+}
+
+static void ets_qdisc_destroy(struct Qdisc *sch)
+{
+	struct ets_sched *q = qdisc_priv(sch);
+	int band;
+
+	ets_offload_destroy(sch);
+	tcf_block_put(q->block);
+	for (band = 0; band < q->nbands; band++)
+		qdisc_put(q->classes[band].qdisc);
+}
+
+static int ets_qdisc_dump(struct Qdisc *sch, struct sk_buff *skb)
+{
+	struct ets_sched *q = qdisc_priv(sch);
+	struct nlattr *opts;
+	struct nlattr *nest;
+	int band;
+	int prio;
+	int err;
+
+	err = ets_offload_dump(sch);
+	if (err)
+		return err;
+
+	opts = nla_nest_start_noflag(skb, TCA_OPTIONS);
+	if (!opts)
+		goto nla_err;
+
+	if (nla_put_u8(skb, TCA_ETS_NBANDS, q->nbands))
+		goto nla_err;
+
+	if (q->nstrict &&
+	    nla_put_u8(skb, TCA_ETS_NSTRICT, q->nstrict))
+		goto nla_err;
+
+	if (q->nbands > q->nstrict) {
+		nest = nla_nest_start(skb, TCA_ETS_QUANTA);
+		if (!nest)
+			goto nla_err;
+
+		for (band = q->nstrict; band < q->nbands; band++) {
+			if (nla_put_u32(skb, TCA_ETS_QUANTA_BAND,
+					q->classes[band].quantum))
+				goto nla_err;
+		}
+
+		nla_nest_end(skb, nest);
+	}
+
+	nest = nla_nest_start(skb, TCA_ETS_PRIOMAP);
+	if (!nest)
+		goto nla_err;
+
+	for (prio = 0; prio <= TC_PRIO_MAX; prio++) {
+		if (nla_put_u8(skb, TCA_ETS_PRIOMAP_BAND, q->prio2band[prio]))
+			goto nla_err;
+	}
+
+	nla_nest_end(skb, nest);
+
+	return nla_nest_end(skb, opts);
+
+nla_err:
+	nla_nest_cancel(skb, opts);
+	return -EMSGSIZE;
+}
+
+static const struct Qdisc_class_ops ets_class_ops = {
+	.change		= ets_class_change,
+	.graft		= ets_class_graft,
+	.leaf		= ets_class_leaf,
+	.find		= ets_class_find,
+	.qlen_notify	= ets_class_qlen_notify,
+	.dump		= ets_class_dump,
+	.dump_stats	= ets_class_dump_stats,
+	.walk		= ets_qdisc_walk,
+	.tcf_block	= ets_qdisc_tcf_block,
+	.bind_tcf	= ets_qdisc_bind_tcf,
+	.unbind_tcf	= ets_qdisc_unbind_tcf,
+};
+
+static struct Qdisc_ops ets_qdisc_ops __read_mostly = {
+	.cl_ops		= &ets_class_ops,
+	.id		= "ets",
+	.priv_size	= sizeof(struct ets_sched),
+	.enqueue	= ets_qdisc_enqueue,
+	.dequeue	= ets_qdisc_dequeue,
+	.peek		= qdisc_peek_dequeued,
+	.change		= ets_qdisc_change,
+	.init		= ets_qdisc_init,
+	.reset		= ets_qdisc_reset,
+	.destroy	= ets_qdisc_destroy,
+	.dump		= ets_qdisc_dump,
+	.owner		= THIS_MODULE,
+};
+
+static int __init ets_init(void)
+{
+	return register_qdisc(&ets_qdisc_ops);
+}
+
+static void __exit ets_exit(void)
+{
+	unregister_qdisc(&ets_qdisc_ops);
+}
+
+module_init(ets_init);
+module_exit(ets_exit);
+MODULE_LICENSE("GPL");