xref: /kernel/linux/linux-5.10/net/sched/sch_ets.c (revision 8c2ecf20)
1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 * net/sched/sch_ets.c         Enhanced Transmission Selection scheduler
4 *
5 * Description
6 * -----------
7 *
8 * The Enhanced Transmission Selection scheduler is a classful queuing
9 * discipline that merges functionality of PRIO and DRR qdiscs in one scheduler.
10 * ETS makes it easy to configure a set of strict and bandwidth-sharing bands to
11 * implement the transmission selection described in 802.1Qaz.
12 *
13 * Although ETS is technically classful, it's not possible to add and remove
14 * classes at will. Instead one specifies number of classes, how many are
15 * PRIO-like and how many DRR-like, and quanta for the latter.
16 *
17 * Algorithm
18 * ---------
19 *
20 * The strict classes, if any, are tried for traffic first: first band 0, if it
21 * has no traffic then band 1, etc.
22 *
23 * When there is no traffic in any of the strict queues, the bandwidth-sharing
24 * ones are tried next. Each band is assigned a deficit counter, initialized to
25 * "quantum" of that band. ETS maintains a list of active bandwidth-sharing
26 * bands whose qdiscs are non-empty. A packet is dequeued from the band at the
27 * head of the list if the packet size is smaller or equal to the deficit
28 * counter. If the counter is too small, it is increased by "quantum" and the
29 * scheduler moves on to the next band in the active list.
30 */
31
32#include <linux/module.h>
33#include <net/gen_stats.h>
34#include <net/netlink.h>
35#include <net/pkt_cls.h>
36#include <net/pkt_sched.h>
37#include <net/sch_generic.h>
38
39struct ets_class {
40	struct list_head alist; /* In struct ets_sched.active. */
41	struct Qdisc *qdisc;
42	u32 quantum;
43	u32 deficit;
44	struct gnet_stats_basic_packed bstats;
45	struct gnet_stats_queue qstats;
46};
47
48struct ets_sched {
49	struct list_head active;
50	struct tcf_proto __rcu *filter_list;
51	struct tcf_block *block;
52	unsigned int nbands;
53	unsigned int nstrict;
54	u8 prio2band[TC_PRIO_MAX + 1];
55	struct ets_class classes[TCQ_ETS_MAX_BANDS];
56};
57
58static const struct nla_policy ets_policy[TCA_ETS_MAX + 1] = {
59	[TCA_ETS_NBANDS] = { .type = NLA_U8 },
60	[TCA_ETS_NSTRICT] = { .type = NLA_U8 },
61	[TCA_ETS_QUANTA] = { .type = NLA_NESTED },
62	[TCA_ETS_PRIOMAP] = { .type = NLA_NESTED },
63};
64
65static const struct nla_policy ets_priomap_policy[TCA_ETS_MAX + 1] = {
66	[TCA_ETS_PRIOMAP_BAND] = { .type = NLA_U8 },
67};
68
69static const struct nla_policy ets_quanta_policy[TCA_ETS_MAX + 1] = {
70	[TCA_ETS_QUANTA_BAND] = { .type = NLA_U32 },
71};
72
73static const struct nla_policy ets_class_policy[TCA_ETS_MAX + 1] = {
74	[TCA_ETS_QUANTA_BAND] = { .type = NLA_U32 },
75};
76
77static int ets_quantum_parse(struct Qdisc *sch, const struct nlattr *attr,
78			     unsigned int *quantum,
79			     struct netlink_ext_ack *extack)
80{
81	*quantum = nla_get_u32(attr);
82	if (!*quantum) {
83		NL_SET_ERR_MSG(extack, "ETS quantum cannot be zero");
84		return -EINVAL;
85	}
86	return 0;
87}
88
89static struct ets_class *
90ets_class_from_arg(struct Qdisc *sch, unsigned long arg)
91{
92	struct ets_sched *q = qdisc_priv(sch);
93
94	return &q->classes[arg - 1];
95}
96
97static u32 ets_class_id(struct Qdisc *sch, const struct ets_class *cl)
98{
99	struct ets_sched *q = qdisc_priv(sch);
100	int band = cl - q->classes;
101
102	return TC_H_MAKE(sch->handle, band + 1);
103}
104
105static void ets_offload_change(struct Qdisc *sch)
106{
107	struct net_device *dev = qdisc_dev(sch);
108	struct ets_sched *q = qdisc_priv(sch);
109	struct tc_ets_qopt_offload qopt;
110	unsigned int w_psum_prev = 0;
111	unsigned int q_psum = 0;
112	unsigned int q_sum = 0;
113	unsigned int quantum;
114	unsigned int w_psum;
115	unsigned int weight;
116	unsigned int i;
117
118	if (!tc_can_offload(dev) || !dev->netdev_ops->ndo_setup_tc)
119		return;
120
121	qopt.command = TC_ETS_REPLACE;
122	qopt.handle = sch->handle;
123	qopt.parent = sch->parent;
124	qopt.replace_params.bands = q->nbands;
125	qopt.replace_params.qstats = &sch->qstats;
126	memcpy(&qopt.replace_params.priomap,
127	       q->prio2band, sizeof(q->prio2band));
128
129	for (i = 0; i < q->nbands; i++)
130		q_sum += q->classes[i].quantum;
131
132	for (i = 0; i < q->nbands; i++) {
133		quantum = q->classes[i].quantum;
134		q_psum += quantum;
135		w_psum = quantum ? q_psum * 100 / q_sum : 0;
136		weight = w_psum - w_psum_prev;
137		w_psum_prev = w_psum;
138
139		qopt.replace_params.quanta[i] = quantum;
140		qopt.replace_params.weights[i] = weight;
141	}
142
143	dev->netdev_ops->ndo_setup_tc(dev, TC_SETUP_QDISC_ETS, &qopt);
144}
145
146static void ets_offload_destroy(struct Qdisc *sch)
147{
148	struct net_device *dev = qdisc_dev(sch);
149	struct tc_ets_qopt_offload qopt;
150
151	if (!tc_can_offload(dev) || !dev->netdev_ops->ndo_setup_tc)
152		return;
153
154	qopt.command = TC_ETS_DESTROY;
155	qopt.handle = sch->handle;
156	qopt.parent = sch->parent;
157	dev->netdev_ops->ndo_setup_tc(dev, TC_SETUP_QDISC_ETS, &qopt);
158}
159
160static void ets_offload_graft(struct Qdisc *sch, struct Qdisc *new,
161			      struct Qdisc *old, unsigned long arg,
162			      struct netlink_ext_ack *extack)
163{
164	struct net_device *dev = qdisc_dev(sch);
165	struct tc_ets_qopt_offload qopt;
166
167	qopt.command = TC_ETS_GRAFT;
168	qopt.handle = sch->handle;
169	qopt.parent = sch->parent;
170	qopt.graft_params.band = arg - 1;
171	qopt.graft_params.child_handle = new->handle;
172
173	qdisc_offload_graft_helper(dev, sch, new, old, TC_SETUP_QDISC_ETS,
174				   &qopt, extack);
175}
176
177static int ets_offload_dump(struct Qdisc *sch)
178{
179	struct tc_ets_qopt_offload qopt;
180
181	qopt.command = TC_ETS_STATS;
182	qopt.handle = sch->handle;
183	qopt.parent = sch->parent;
184	qopt.stats.bstats = &sch->bstats;
185	qopt.stats.qstats = &sch->qstats;
186
187	return qdisc_offload_dump_helper(sch, TC_SETUP_QDISC_ETS, &qopt);
188}
189
190static bool ets_class_is_strict(struct ets_sched *q, const struct ets_class *cl)
191{
192	unsigned int band = cl - q->classes;
193
194	return band < q->nstrict;
195}
196
197static int ets_class_change(struct Qdisc *sch, u32 classid, u32 parentid,
198			    struct nlattr **tca, unsigned long *arg,
199			    struct netlink_ext_ack *extack)
200{
201	struct ets_class *cl = ets_class_from_arg(sch, *arg);
202	struct ets_sched *q = qdisc_priv(sch);
203	struct nlattr *opt = tca[TCA_OPTIONS];
204	struct nlattr *tb[TCA_ETS_MAX + 1];
205	unsigned int quantum;
206	int err;
207
208	/* Classes can be added and removed only through Qdisc_ops.change
209	 * interface.
210	 */
211	if (!cl) {
212		NL_SET_ERR_MSG(extack, "Fine-grained class addition and removal is not supported");
213		return -EOPNOTSUPP;
214	}
215
216	if (!opt) {
217		NL_SET_ERR_MSG(extack, "ETS options are required for this operation");
218		return -EINVAL;
219	}
220
221	err = nla_parse_nested(tb, TCA_ETS_MAX, opt, ets_class_policy, extack);
222	if (err < 0)
223		return err;
224
225	if (!tb[TCA_ETS_QUANTA_BAND])
226		/* Nothing to configure. */
227		return 0;
228
229	if (ets_class_is_strict(q, cl)) {
230		NL_SET_ERR_MSG(extack, "Strict bands do not have a configurable quantum");
231		return -EINVAL;
232	}
233
234	err = ets_quantum_parse(sch, tb[TCA_ETS_QUANTA_BAND], &quantum,
235				extack);
236	if (err)
237		return err;
238
239	sch_tree_lock(sch);
240	cl->quantum = quantum;
241	sch_tree_unlock(sch);
242
243	ets_offload_change(sch);
244	return 0;
245}
246
247static int ets_class_graft(struct Qdisc *sch, unsigned long arg,
248			   struct Qdisc *new, struct Qdisc **old,
249			   struct netlink_ext_ack *extack)
250{
251	struct ets_class *cl = ets_class_from_arg(sch, arg);
252
253	if (!new) {
254		new = qdisc_create_dflt(sch->dev_queue, &pfifo_qdisc_ops,
255					ets_class_id(sch, cl), NULL);
256		if (!new)
257			new = &noop_qdisc;
258		else
259			qdisc_hash_add(new, true);
260	}
261
262	*old = qdisc_replace(sch, new, &cl->qdisc);
263	ets_offload_graft(sch, new, *old, arg, extack);
264	return 0;
265}
266
267static struct Qdisc *ets_class_leaf(struct Qdisc *sch, unsigned long arg)
268{
269	struct ets_class *cl = ets_class_from_arg(sch, arg);
270
271	return cl->qdisc;
272}
273
274static unsigned long ets_class_find(struct Qdisc *sch, u32 classid)
275{
276	unsigned long band = TC_H_MIN(classid);
277	struct ets_sched *q = qdisc_priv(sch);
278
279	if (band - 1 >= q->nbands)
280		return 0;
281	return band;
282}
283
284static void ets_class_qlen_notify(struct Qdisc *sch, unsigned long arg)
285{
286	struct ets_class *cl = ets_class_from_arg(sch, arg);
287	struct ets_sched *q = qdisc_priv(sch);
288
289	/* We get notified about zero-length child Qdiscs as well if they are
290	 * offloaded. Those aren't on the active list though, so don't attempt
291	 * to remove them.
292	 */
293	if (!ets_class_is_strict(q, cl) && sch->q.qlen)
294		list_del(&cl->alist);
295}
296
297static int ets_class_dump(struct Qdisc *sch, unsigned long arg,
298			  struct sk_buff *skb, struct tcmsg *tcm)
299{
300	struct ets_class *cl = ets_class_from_arg(sch, arg);
301	struct ets_sched *q = qdisc_priv(sch);
302	struct nlattr *nest;
303
304	tcm->tcm_parent = TC_H_ROOT;
305	tcm->tcm_handle = ets_class_id(sch, cl);
306	tcm->tcm_info = cl->qdisc->handle;
307
308	nest = nla_nest_start_noflag(skb, TCA_OPTIONS);
309	if (!nest)
310		goto nla_put_failure;
311	if (!ets_class_is_strict(q, cl)) {
312		if (nla_put_u32(skb, TCA_ETS_QUANTA_BAND, cl->quantum))
313			goto nla_put_failure;
314	}
315	return nla_nest_end(skb, nest);
316
317nla_put_failure:
318	nla_nest_cancel(skb, nest);
319	return -EMSGSIZE;
320}
321
322static int ets_class_dump_stats(struct Qdisc *sch, unsigned long arg,
323				struct gnet_dump *d)
324{
325	struct ets_class *cl = ets_class_from_arg(sch, arg);
326	struct Qdisc *cl_q = cl->qdisc;
327
328	if (gnet_stats_copy_basic(qdisc_root_sleeping_running(sch),
329				  d, NULL, &cl_q->bstats) < 0 ||
330	    qdisc_qstats_copy(d, cl_q) < 0)
331		return -1;
332
333	return 0;
334}
335
336static void ets_qdisc_walk(struct Qdisc *sch, struct qdisc_walker *arg)
337{
338	struct ets_sched *q = qdisc_priv(sch);
339	int i;
340
341	if (arg->stop)
342		return;
343
344	for (i = 0; i < q->nbands; i++) {
345		if (arg->count < arg->skip) {
346			arg->count++;
347			continue;
348		}
349		if (arg->fn(sch, i + 1, arg) < 0) {
350			arg->stop = 1;
351			break;
352		}
353		arg->count++;
354	}
355}
356
357static struct tcf_block *
358ets_qdisc_tcf_block(struct Qdisc *sch, unsigned long cl,
359		    struct netlink_ext_ack *extack)
360{
361	struct ets_sched *q = qdisc_priv(sch);
362
363	if (cl) {
364		NL_SET_ERR_MSG(extack, "ETS classid must be zero");
365		return NULL;
366	}
367
368	return q->block;
369}
370
371static unsigned long ets_qdisc_bind_tcf(struct Qdisc *sch, unsigned long parent,
372					u32 classid)
373{
374	return ets_class_find(sch, classid);
375}
376
377static void ets_qdisc_unbind_tcf(struct Qdisc *sch, unsigned long arg)
378{
379}
380
381static struct ets_class *ets_classify(struct sk_buff *skb, struct Qdisc *sch,
382				      int *qerr)
383{
384	struct ets_sched *q = qdisc_priv(sch);
385	u32 band = skb->priority;
386	struct tcf_result res;
387	struct tcf_proto *fl;
388	int err;
389
390	*qerr = NET_XMIT_SUCCESS | __NET_XMIT_BYPASS;
391	if (TC_H_MAJ(skb->priority) != sch->handle) {
392		fl = rcu_dereference_bh(q->filter_list);
393		err = tcf_classify(skb, fl, &res, false);
394#ifdef CONFIG_NET_CLS_ACT
395		switch (err) {
396		case TC_ACT_STOLEN:
397		case TC_ACT_QUEUED:
398		case TC_ACT_TRAP:
399			*qerr = NET_XMIT_SUCCESS | __NET_XMIT_STOLEN;
400			fallthrough;
401		case TC_ACT_SHOT:
402			return NULL;
403		}
404#endif
405		if (!fl || err < 0) {
406			if (TC_H_MAJ(band))
407				band = 0;
408			return &q->classes[q->prio2band[band & TC_PRIO_MAX]];
409		}
410		band = res.classid;
411	}
412	band = TC_H_MIN(band) - 1;
413	if (band >= q->nbands)
414		return &q->classes[q->prio2band[0]];
415	return &q->classes[band];
416}
417
418static int ets_qdisc_enqueue(struct sk_buff *skb, struct Qdisc *sch,
419			     struct sk_buff **to_free)
420{
421	unsigned int len = qdisc_pkt_len(skb);
422	struct ets_sched *q = qdisc_priv(sch);
423	struct ets_class *cl;
424	int err = 0;
425	bool first;
426
427	cl = ets_classify(skb, sch, &err);
428	if (!cl) {
429		if (err & __NET_XMIT_BYPASS)
430			qdisc_qstats_drop(sch);
431		__qdisc_drop(skb, to_free);
432		return err;
433	}
434
435	first = !cl->qdisc->q.qlen;
436	err = qdisc_enqueue(skb, cl->qdisc, to_free);
437	if (unlikely(err != NET_XMIT_SUCCESS)) {
438		if (net_xmit_drop_count(err)) {
439			cl->qstats.drops++;
440			qdisc_qstats_drop(sch);
441		}
442		return err;
443	}
444
445	if (first && !ets_class_is_strict(q, cl)) {
446		list_add_tail(&cl->alist, &q->active);
447		cl->deficit = cl->quantum;
448	}
449
450	sch->qstats.backlog += len;
451	sch->q.qlen++;
452	return err;
453}
454
455static struct sk_buff *
456ets_qdisc_dequeue_skb(struct Qdisc *sch, struct sk_buff *skb)
457{
458	qdisc_bstats_update(sch, skb);
459	qdisc_qstats_backlog_dec(sch, skb);
460	sch->q.qlen--;
461	return skb;
462}
463
464static struct sk_buff *ets_qdisc_dequeue(struct Qdisc *sch)
465{
466	struct ets_sched *q = qdisc_priv(sch);
467	struct ets_class *cl;
468	struct sk_buff *skb;
469	unsigned int band;
470	unsigned int len;
471
472	while (1) {
473		for (band = 0; band < q->nstrict; band++) {
474			cl = &q->classes[band];
475			skb = qdisc_dequeue_peeked(cl->qdisc);
476			if (skb)
477				return ets_qdisc_dequeue_skb(sch, skb);
478		}
479
480		if (list_empty(&q->active))
481			goto out;
482
483		cl = list_first_entry(&q->active, struct ets_class, alist);
484		skb = cl->qdisc->ops->peek(cl->qdisc);
485		if (!skb) {
486			qdisc_warn_nonwc(__func__, cl->qdisc);
487			goto out;
488		}
489
490		len = qdisc_pkt_len(skb);
491		if (len <= cl->deficit) {
492			cl->deficit -= len;
493			skb = qdisc_dequeue_peeked(cl->qdisc);
494			if (unlikely(!skb))
495				goto out;
496			if (cl->qdisc->q.qlen == 0)
497				list_del(&cl->alist);
498			return ets_qdisc_dequeue_skb(sch, skb);
499		}
500
501		cl->deficit += cl->quantum;
502		list_move_tail(&cl->alist, &q->active);
503	}
504out:
505	return NULL;
506}
507
508static int ets_qdisc_priomap_parse(struct nlattr *priomap_attr,
509				   unsigned int nbands, u8 *priomap,
510				   struct netlink_ext_ack *extack)
511{
512	const struct nlattr *attr;
513	int prio = 0;
514	u8 band;
515	int rem;
516	int err;
517
518	err = __nla_validate_nested(priomap_attr, TCA_ETS_MAX,
519				    ets_priomap_policy, NL_VALIDATE_STRICT,
520				    extack);
521	if (err)
522		return err;
523
524	nla_for_each_nested(attr, priomap_attr, rem) {
525		switch (nla_type(attr)) {
526		case TCA_ETS_PRIOMAP_BAND:
527			if (prio > TC_PRIO_MAX) {
528				NL_SET_ERR_MSG_MOD(extack, "Too many priorities in ETS priomap");
529				return -EINVAL;
530			}
531			band = nla_get_u8(attr);
532			if (band >= nbands) {
533				NL_SET_ERR_MSG_MOD(extack, "Invalid band number in ETS priomap");
534				return -EINVAL;
535			}
536			priomap[prio++] = band;
537			break;
538		default:
539			WARN_ON_ONCE(1); /* Validate should have caught this. */
540			return -EINVAL;
541		}
542	}
543
544	return 0;
545}
546
547static int ets_qdisc_quanta_parse(struct Qdisc *sch, struct nlattr *quanta_attr,
548				  unsigned int nbands, unsigned int nstrict,
549				  unsigned int *quanta,
550				  struct netlink_ext_ack *extack)
551{
552	const struct nlattr *attr;
553	int band = nstrict;
554	int rem;
555	int err;
556
557	err = __nla_validate_nested(quanta_attr, TCA_ETS_MAX,
558				    ets_quanta_policy, NL_VALIDATE_STRICT,
559				    extack);
560	if (err < 0)
561		return err;
562
563	nla_for_each_nested(attr, quanta_attr, rem) {
564		switch (nla_type(attr)) {
565		case TCA_ETS_QUANTA_BAND:
566			if (band >= nbands) {
567				NL_SET_ERR_MSG_MOD(extack, "ETS quanta has more values than bands");
568				return -EINVAL;
569			}
570			err = ets_quantum_parse(sch, attr, &quanta[band++],
571						extack);
572			if (err)
573				return err;
574			break;
575		default:
576			WARN_ON_ONCE(1); /* Validate should have caught this. */
577			return -EINVAL;
578		}
579	}
580
581	return 0;
582}
583
584static int ets_qdisc_change(struct Qdisc *sch, struct nlattr *opt,
585			    struct netlink_ext_ack *extack)
586{
587	unsigned int quanta[TCQ_ETS_MAX_BANDS] = {0};
588	struct Qdisc *queues[TCQ_ETS_MAX_BANDS];
589	struct ets_sched *q = qdisc_priv(sch);
590	struct nlattr *tb[TCA_ETS_MAX + 1];
591	unsigned int oldbands = q->nbands;
592	u8 priomap[TC_PRIO_MAX + 1];
593	unsigned int nstrict = 0;
594	unsigned int nbands;
595	unsigned int i;
596	int err;
597
598	if (!opt) {
599		NL_SET_ERR_MSG(extack, "ETS options are required for this operation");
600		return -EINVAL;
601	}
602
603	err = nla_parse_nested(tb, TCA_ETS_MAX, opt, ets_policy, extack);
604	if (err < 0)
605		return err;
606
607	if (!tb[TCA_ETS_NBANDS]) {
608		NL_SET_ERR_MSG_MOD(extack, "Number of bands is a required argument");
609		return -EINVAL;
610	}
611	nbands = nla_get_u8(tb[TCA_ETS_NBANDS]);
612	if (nbands < 1 || nbands > TCQ_ETS_MAX_BANDS) {
613		NL_SET_ERR_MSG_MOD(extack, "Invalid number of bands");
614		return -EINVAL;
615	}
616	/* Unless overridden, traffic goes to the last band. */
617	memset(priomap, nbands - 1, sizeof(priomap));
618
619	if (tb[TCA_ETS_NSTRICT]) {
620		nstrict = nla_get_u8(tb[TCA_ETS_NSTRICT]);
621		if (nstrict > nbands) {
622			NL_SET_ERR_MSG_MOD(extack, "Invalid number of strict bands");
623			return -EINVAL;
624		}
625	}
626
627	if (tb[TCA_ETS_PRIOMAP]) {
628		err = ets_qdisc_priomap_parse(tb[TCA_ETS_PRIOMAP],
629					      nbands, priomap, extack);
630		if (err)
631			return err;
632	}
633
634	if (tb[TCA_ETS_QUANTA]) {
635		err = ets_qdisc_quanta_parse(sch, tb[TCA_ETS_QUANTA],
636					     nbands, nstrict, quanta, extack);
637		if (err)
638			return err;
639	}
640	/* If there are more bands than strict + quanta provided, the remaining
641	 * ones are ETS with quantum of MTU. Initialize the missing values here.
642	 */
643	for (i = nstrict; i < nbands; i++) {
644		if (!quanta[i])
645			quanta[i] = psched_mtu(qdisc_dev(sch));
646	}
647
648	/* Before commit, make sure we can allocate all new qdiscs */
649	for (i = oldbands; i < nbands; i++) {
650		queues[i] = qdisc_create_dflt(sch->dev_queue, &pfifo_qdisc_ops,
651					      ets_class_id(sch, &q->classes[i]),
652					      extack);
653		if (!queues[i]) {
654			while (i > oldbands)
655				qdisc_put(queues[--i]);
656			return -ENOMEM;
657		}
658	}
659
660	sch_tree_lock(sch);
661
662	q->nbands = nbands;
663	for (i = nstrict; i < q->nstrict; i++) {
664		INIT_LIST_HEAD(&q->classes[i].alist);
665		if (q->classes[i].qdisc->q.qlen) {
666			list_add_tail(&q->classes[i].alist, &q->active);
667			q->classes[i].deficit = quanta[i];
668		}
669	}
670	for (i = q->nbands; i < oldbands; i++) {
671		if (i >= q->nstrict && q->classes[i].qdisc->q.qlen)
672			list_del(&q->classes[i].alist);
673		qdisc_tree_flush_backlog(q->classes[i].qdisc);
674	}
675	q->nstrict = nstrict;
676	memcpy(q->prio2band, priomap, sizeof(priomap));
677
678	for (i = 0; i < q->nbands; i++)
679		q->classes[i].quantum = quanta[i];
680
681	for (i = oldbands; i < q->nbands; i++) {
682		q->classes[i].qdisc = queues[i];
683		if (q->classes[i].qdisc != &noop_qdisc)
684			qdisc_hash_add(q->classes[i].qdisc, true);
685	}
686
687	sch_tree_unlock(sch);
688
689	ets_offload_change(sch);
690	for (i = q->nbands; i < oldbands; i++) {
691		qdisc_put(q->classes[i].qdisc);
692		memset(&q->classes[i], 0, sizeof(q->classes[i]));
693	}
694	return 0;
695}
696
697static int ets_qdisc_init(struct Qdisc *sch, struct nlattr *opt,
698			  struct netlink_ext_ack *extack)
699{
700	struct ets_sched *q = qdisc_priv(sch);
701	int err;
702
703	if (!opt)
704		return -EINVAL;
705
706	err = tcf_block_get(&q->block, &q->filter_list, sch, extack);
707	if (err)
708		return err;
709
710	INIT_LIST_HEAD(&q->active);
711	return ets_qdisc_change(sch, opt, extack);
712}
713
714static void ets_qdisc_reset(struct Qdisc *sch)
715{
716	struct ets_sched *q = qdisc_priv(sch);
717	int band;
718
719	for (band = q->nstrict; band < q->nbands; band++) {
720		if (q->classes[band].qdisc->q.qlen)
721			list_del(&q->classes[band].alist);
722	}
723	for (band = 0; band < q->nbands; band++)
724		qdisc_reset(q->classes[band].qdisc);
725}
726
727static void ets_qdisc_destroy(struct Qdisc *sch)
728{
729	struct ets_sched *q = qdisc_priv(sch);
730	int band;
731
732	ets_offload_destroy(sch);
733	tcf_block_put(q->block);
734	for (band = 0; band < q->nbands; band++)
735		qdisc_put(q->classes[band].qdisc);
736}
737
738static int ets_qdisc_dump(struct Qdisc *sch, struct sk_buff *skb)
739{
740	struct ets_sched *q = qdisc_priv(sch);
741	struct nlattr *opts;
742	struct nlattr *nest;
743	int band;
744	int prio;
745	int err;
746
747	err = ets_offload_dump(sch);
748	if (err)
749		return err;
750
751	opts = nla_nest_start_noflag(skb, TCA_OPTIONS);
752	if (!opts)
753		goto nla_err;
754
755	if (nla_put_u8(skb, TCA_ETS_NBANDS, q->nbands))
756		goto nla_err;
757
758	if (q->nstrict &&
759	    nla_put_u8(skb, TCA_ETS_NSTRICT, q->nstrict))
760		goto nla_err;
761
762	if (q->nbands > q->nstrict) {
763		nest = nla_nest_start(skb, TCA_ETS_QUANTA);
764		if (!nest)
765			goto nla_err;
766
767		for (band = q->nstrict; band < q->nbands; band++) {
768			if (nla_put_u32(skb, TCA_ETS_QUANTA_BAND,
769					q->classes[band].quantum))
770				goto nla_err;
771		}
772
773		nla_nest_end(skb, nest);
774	}
775
776	nest = nla_nest_start(skb, TCA_ETS_PRIOMAP);
777	if (!nest)
778		goto nla_err;
779
780	for (prio = 0; prio <= TC_PRIO_MAX; prio++) {
781		if (nla_put_u8(skb, TCA_ETS_PRIOMAP_BAND, q->prio2band[prio]))
782			goto nla_err;
783	}
784
785	nla_nest_end(skb, nest);
786
787	return nla_nest_end(skb, opts);
788
789nla_err:
790	nla_nest_cancel(skb, opts);
791	return -EMSGSIZE;
792}
793
794static const struct Qdisc_class_ops ets_class_ops = {
795	.change		= ets_class_change,
796	.graft		= ets_class_graft,
797	.leaf		= ets_class_leaf,
798	.find		= ets_class_find,
799	.qlen_notify	= ets_class_qlen_notify,
800	.dump		= ets_class_dump,
801	.dump_stats	= ets_class_dump_stats,
802	.walk		= ets_qdisc_walk,
803	.tcf_block	= ets_qdisc_tcf_block,
804	.bind_tcf	= ets_qdisc_bind_tcf,
805	.unbind_tcf	= ets_qdisc_unbind_tcf,
806};
807
808static struct Qdisc_ops ets_qdisc_ops __read_mostly = {
809	.cl_ops		= &ets_class_ops,
810	.id		= "ets",
811	.priv_size	= sizeof(struct ets_sched),
812	.enqueue	= ets_qdisc_enqueue,
813	.dequeue	= ets_qdisc_dequeue,
814	.peek		= qdisc_peek_dequeued,
815	.change		= ets_qdisc_change,
816	.init		= ets_qdisc_init,
817	.reset		= ets_qdisc_reset,
818	.destroy	= ets_qdisc_destroy,
819	.dump		= ets_qdisc_dump,
820	.owner		= THIS_MODULE,
821};
822
823static int __init ets_init(void)
824{
825	return register_qdisc(&ets_qdisc_ops);
826}
827
828static void __exit ets_exit(void)
829{
830	unregister_qdisc(&ets_qdisc_ops);
831}
832
833module_init(ets_init);
834module_exit(ets_exit);
835MODULE_LICENSE("GPL");
836