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10#include <linux/bitops.h>
11#include <linux/module.h>
12#include <linux/types.h>
13#include <linux/kernel.h>
14#include <linux/sched.h>
15#include <linux/string.h>
16#include <linux/errno.h>
17#include <linux/netdevice.h>
18#include <linux/skbuff.h>
19#include <linux/rtnetlink.h>
20#include <linux/init.h>
21#include <linux/rcupdate.h>
22#include <linux/list.h>
23#include <linux/slab.h>
24#include <linux/if_vlan.h>
25#include <linux/skb_array.h>
26#include <linux/if_macvlan.h>
27#include <net/sch_generic.h>
28#include <net/pkt_sched.h>
29#include <net/dst.h>
30#include <trace/events/qdisc.h>
31#include <trace/events/net.h>
32#include <net/xfrm.h>
33
34
35const struct Qdisc_ops *default_qdisc_ops = &pfifo_fast_ops;
36EXPORT_SYMBOL(default_qdisc_ops);
37
38
39
40
41
42
43
44
45
46
47
48
49#define SKB_XOFF_MAGIC ((struct sk_buff *)1UL)
50
51static inline struct sk_buff *__skb_dequeue_bad_txq(struct Qdisc *q)
52{
53 const struct netdev_queue *txq = q->dev_queue;
54 spinlock_t *lock = NULL;
55 struct sk_buff *skb;
56
57 if (q->flags & TCQ_F_NOLOCK) {
58 lock = qdisc_lock(q);
59 spin_lock(lock);
60 }
61
62 skb = skb_peek(&q->skb_bad_txq);
63 if (skb) {
64
65 txq = skb_get_tx_queue(txq->dev, skb);
66 if (!netif_xmit_frozen_or_stopped(txq)) {
67 skb = __skb_dequeue(&q->skb_bad_txq);
68 if (qdisc_is_percpu_stats(q)) {
69 qdisc_qstats_cpu_backlog_dec(q, skb);
70 qdisc_qstats_cpu_qlen_dec(q);
71 } else {
72 qdisc_qstats_backlog_dec(q, skb);
73 q->q.qlen--;
74 }
75 } else {
76 skb = SKB_XOFF_MAGIC;
77 }
78 }
79
80 if (lock)
81 spin_unlock(lock);
82
83 return skb;
84}
85
86static inline struct sk_buff *qdisc_dequeue_skb_bad_txq(struct Qdisc *q)
87{
88 struct sk_buff *skb = skb_peek(&q->skb_bad_txq);
89
90 if (unlikely(skb))
91 skb = __skb_dequeue_bad_txq(q);
92
93 return skb;
94}
95
96static inline void qdisc_enqueue_skb_bad_txq(struct Qdisc *q,
97 struct sk_buff *skb)
98{
99 spinlock_t *lock = NULL;
100
101 if (q->flags & TCQ_F_NOLOCK) {
102 lock = qdisc_lock(q);
103 spin_lock(lock);
104 }
105
106 __skb_queue_tail(&q->skb_bad_txq, skb);
107
108 if (qdisc_is_percpu_stats(q)) {
109 qdisc_qstats_cpu_backlog_inc(q, skb);
110 qdisc_qstats_cpu_qlen_inc(q);
111 } else {
112 qdisc_qstats_backlog_inc(q, skb);
113 q->q.qlen++;
114 }
115
116 if (lock)
117 spin_unlock(lock);
118}
119
120static inline void dev_requeue_skb(struct sk_buff *skb, struct Qdisc *q)
121{
122 spinlock_t *lock = NULL;
123
124 if (q->flags & TCQ_F_NOLOCK) {
125 lock = qdisc_lock(q);
126 spin_lock(lock);
127 }
128
129 while (skb) {
130 struct sk_buff *next = skb->next;
131
132 __skb_queue_tail(&q->gso_skb, skb);
133
134
135 if (qdisc_is_percpu_stats(q)) {
136 qdisc_qstats_cpu_requeues_inc(q);
137 qdisc_qstats_cpu_backlog_inc(q, skb);
138 qdisc_qstats_cpu_qlen_inc(q);
139 } else {
140 q->qstats.requeues++;
141 qdisc_qstats_backlog_inc(q, skb);
142 q->q.qlen++;
143 }
144
145 skb = next;
146 }
147 if (lock)
148 spin_unlock(lock);
149 __netif_schedule(q);
150}
151
152static void try_bulk_dequeue_skb(struct Qdisc *q,
153 struct sk_buff *skb,
154 const struct netdev_queue *txq,
155 int *packets)
156{
157 int bytelimit = qdisc_avail_bulklimit(txq) - skb->len;
158
159 while (bytelimit > 0) {
160 struct sk_buff *nskb = q->dequeue(q);
161
162 if (!nskb)
163 break;
164
165 bytelimit -= nskb->len;
166 skb->next = nskb;
167 skb = nskb;
168 (*packets)++;
169 }
170 skb_mark_not_on_list(skb);
171}
172
173
174
175
176static void try_bulk_dequeue_skb_slow(struct Qdisc *q,
177 struct sk_buff *skb,
178 int *packets)
179{
180 int mapping = skb_get_queue_mapping(skb);
181 struct sk_buff *nskb;
182 int cnt = 0;
183
184 do {
185 nskb = q->dequeue(q);
186 if (!nskb)
187 break;
188 if (unlikely(skb_get_queue_mapping(nskb) != mapping)) {
189 qdisc_enqueue_skb_bad_txq(q, nskb);
190 break;
191 }
192 skb->next = nskb;
193 skb = nskb;
194 } while (++cnt < 8);
195 (*packets) += cnt;
196 skb_mark_not_on_list(skb);
197}
198
199
200
201
202static struct sk_buff *dequeue_skb(struct Qdisc *q, bool *validate,
203 int *packets)
204{
205 const struct netdev_queue *txq = q->dev_queue;
206 struct sk_buff *skb = NULL;
207
208 *packets = 1;
209 if (unlikely(!skb_queue_empty(&q->gso_skb))) {
210 spinlock_t *lock = NULL;
211
212 if (q->flags & TCQ_F_NOLOCK) {
213 lock = qdisc_lock(q);
214 spin_lock(lock);
215 }
216
217 skb = skb_peek(&q->gso_skb);
218
219
220
221
222 if (!skb) {
223 if (lock)
224 spin_unlock(lock);
225 goto validate;
226 }
227
228
229 *validate = false;
230 if (xfrm_offload(skb))
231 *validate = true;
232
233 txq = skb_get_tx_queue(txq->dev, skb);
234 if (!netif_xmit_frozen_or_stopped(txq)) {
235 skb = __skb_dequeue(&q->gso_skb);
236 if (qdisc_is_percpu_stats(q)) {
237 qdisc_qstats_cpu_backlog_dec(q, skb);
238 qdisc_qstats_cpu_qlen_dec(q);
239 } else {
240 qdisc_qstats_backlog_dec(q, skb);
241 q->q.qlen--;
242 }
243 } else {
244 skb = NULL;
245 }
246 if (lock)
247 spin_unlock(lock);
248 goto trace;
249 }
250validate:
251 *validate = true;
252
253 if ((q->flags & TCQ_F_ONETXQUEUE) &&
254 netif_xmit_frozen_or_stopped(txq))
255 return skb;
256
257 skb = qdisc_dequeue_skb_bad_txq(q);
258 if (unlikely(skb)) {
259 if (skb == SKB_XOFF_MAGIC)
260 return NULL;
261 goto bulk;
262 }
263 skb = q->dequeue(q);
264 if (skb) {
265bulk:
266 if (qdisc_may_bulk(q))
267 try_bulk_dequeue_skb(q, skb, txq, packets);
268 else
269 try_bulk_dequeue_skb_slow(q, skb, packets);
270 }
271trace:
272 trace_qdisc_dequeue(q, txq, *packets, skb);
273 return skb;
274}
275
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283
284
285bool sch_direct_xmit(struct sk_buff *skb, struct Qdisc *q,
286 struct net_device *dev, struct netdev_queue *txq,
287 spinlock_t *root_lock, bool validate)
288{
289 int ret = NETDEV_TX_BUSY;
290 bool again = false;
291
292
293 if (root_lock)
294 spin_unlock(root_lock);
295
296
297 if (validate)
298 skb = validate_xmit_skb_list(skb, dev, &again);
299
300#ifdef CONFIG_XFRM_OFFLOAD
301 if (unlikely(again)) {
302 if (root_lock)
303 spin_lock(root_lock);
304
305 dev_requeue_skb(skb, q);
306 return false;
307 }
308#endif
309
310 if (likely(skb)) {
311 HARD_TX_LOCK(dev, txq, smp_processor_id());
312 if (!netif_xmit_frozen_or_stopped(txq))
313 skb = dev_hard_start_xmit(skb, dev, txq, &ret);
314
315 HARD_TX_UNLOCK(dev, txq);
316 } else {
317 if (root_lock)
318 spin_lock(root_lock);
319 return true;
320 }
321
322 if (root_lock)
323 spin_lock(root_lock);
324
325 if (!dev_xmit_complete(ret)) {
326
327 if (unlikely(ret != NETDEV_TX_BUSY))
328 net_warn_ratelimited("BUG %s code %d qlen %d\n",
329 dev->name, ret, q->q.qlen);
330
331 dev_requeue_skb(skb, q);
332 return false;
333 }
334
335 return true;
336}
337
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354
355
356
357static inline bool qdisc_restart(struct Qdisc *q, int *packets)
358{
359 spinlock_t *root_lock = NULL;
360 struct netdev_queue *txq;
361 struct net_device *dev;
362 struct sk_buff *skb;
363 bool validate;
364
365
366 skb = dequeue_skb(q, &validate, packets);
367 if (unlikely(!skb))
368 return false;
369
370 if (!(q->flags & TCQ_F_NOLOCK))
371 root_lock = qdisc_lock(q);
372
373 dev = qdisc_dev(q);
374 txq = skb_get_tx_queue(dev, skb);
375
376 return sch_direct_xmit(skb, q, dev, txq, root_lock, validate);
377}
378
379void __qdisc_run(struct Qdisc *q)
380{
381 int quota = dev_tx_weight;
382 int packets;
383
384 while (qdisc_restart(q, &packets)) {
385
386
387
388
389
390 quota -= packets;
391 if (quota <= 0 || need_resched()) {
392 __netif_schedule(q);
393 break;
394 }
395 }
396}
397
398unsigned long dev_trans_start(struct net_device *dev)
399{
400 unsigned long val, res;
401 unsigned int i;
402
403 if (is_vlan_dev(dev))
404 dev = vlan_dev_real_dev(dev);
405 else if (netif_is_macvlan(dev))
406 dev = macvlan_dev_real_dev(dev);
407 res = netdev_get_tx_queue(dev, 0)->trans_start;
408 for (i = 1; i < dev->num_tx_queues; i++) {
409 val = netdev_get_tx_queue(dev, i)->trans_start;
410 if (val && time_after(val, res))
411 res = val;
412 }
413
414 return res;
415}
416EXPORT_SYMBOL(dev_trans_start);
417
418static void dev_watchdog(struct timer_list *t)
419{
420 struct net_device *dev = from_timer(dev, t, watchdog_timer);
421
422 netif_tx_lock(dev);
423 if (!qdisc_tx_is_noop(dev)) {
424 if (netif_device_present(dev) &&
425 netif_running(dev) &&
426 netif_carrier_ok(dev)) {
427 int some_queue_timedout = 0;
428 unsigned int i;
429 unsigned long trans_start;
430
431 for (i = 0; i < dev->num_tx_queues; i++) {
432 struct netdev_queue *txq;
433
434 txq = netdev_get_tx_queue(dev, i);
435 trans_start = txq->trans_start;
436 if (netif_xmit_stopped(txq) &&
437 time_after(jiffies, (trans_start +
438 dev->watchdog_timeo))) {
439 some_queue_timedout = 1;
440 txq->trans_timeout++;
441 break;
442 }
443 }
444
445 if (some_queue_timedout) {
446 trace_net_dev_xmit_timeout(dev, i);
447 WARN_ONCE(1, KERN_INFO "NETDEV WATCHDOG: %s (%s): transmit queue %u timed out\n",
448 dev->name, netdev_drivername(dev), i);
449 dev->netdev_ops->ndo_tx_timeout(dev);
450 }
451 if (!mod_timer(&dev->watchdog_timer,
452 round_jiffies(jiffies +
453 dev->watchdog_timeo)))
454 dev_hold(dev);
455 }
456 }
457 netif_tx_unlock(dev);
458
459 dev_put(dev);
460}
461
462void __netdev_watchdog_up(struct net_device *dev)
463{
464 if (dev->netdev_ops->ndo_tx_timeout) {
465 if (dev->watchdog_timeo <= 0)
466 dev->watchdog_timeo = 5*HZ;
467 if (!mod_timer(&dev->watchdog_timer,
468 round_jiffies(jiffies + dev->watchdog_timeo)))
469 dev_hold(dev);
470 }
471}
472
473static void dev_watchdog_up(struct net_device *dev)
474{
475 __netdev_watchdog_up(dev);
476}
477
478static void dev_watchdog_down(struct net_device *dev)
479{
480 netif_tx_lock_bh(dev);
481 if (del_timer(&dev->watchdog_timer))
482 dev_put(dev);
483 netif_tx_unlock_bh(dev);
484}
485
486
487
488
489
490
491
492void netif_carrier_on(struct net_device *dev)
493{
494 if (test_and_clear_bit(__LINK_STATE_NOCARRIER, &dev->state)) {
495 if (dev->reg_state == NETREG_UNINITIALIZED)
496 return;
497 atomic_inc(&dev->carrier_up_count);
498 linkwatch_fire_event(dev);
499 if (netif_running(dev))
500 __netdev_watchdog_up(dev);
501 }
502}
503EXPORT_SYMBOL(netif_carrier_on);
504
505
506
507
508
509
510
511void netif_carrier_off(struct net_device *dev)
512{
513 if (!test_and_set_bit(__LINK_STATE_NOCARRIER, &dev->state)) {
514 if (dev->reg_state == NETREG_UNINITIALIZED)
515 return;
516 atomic_inc(&dev->carrier_down_count);
517 linkwatch_fire_event(dev);
518 }
519}
520EXPORT_SYMBOL(netif_carrier_off);
521
522
523
524
525
526
527static int noop_enqueue(struct sk_buff *skb, struct Qdisc *qdisc,
528 struct sk_buff **to_free)
529{
530 __qdisc_drop(skb, to_free);
531 return NET_XMIT_CN;
532}
533
534static struct sk_buff *noop_dequeue(struct Qdisc *qdisc)
535{
536 return NULL;
537}
538
539struct Qdisc_ops noop_qdisc_ops __read_mostly = {
540 .id = "noop",
541 .priv_size = 0,
542 .enqueue = noop_enqueue,
543 .dequeue = noop_dequeue,
544 .peek = noop_dequeue,
545 .owner = THIS_MODULE,
546};
547
548static struct netdev_queue noop_netdev_queue = {
549 RCU_POINTER_INITIALIZER(qdisc, &noop_qdisc),
550 .qdisc_sleeping = &noop_qdisc,
551};
552
553struct Qdisc noop_qdisc = {
554 .enqueue = noop_enqueue,
555 .dequeue = noop_dequeue,
556 .flags = TCQ_F_BUILTIN,
557 .ops = &noop_qdisc_ops,
558 .q.lock = __SPIN_LOCK_UNLOCKED(noop_qdisc.q.lock),
559 .dev_queue = &noop_netdev_queue,
560 .running = SEQCNT_ZERO(noop_qdisc.running),
561 .busylock = __SPIN_LOCK_UNLOCKED(noop_qdisc.busylock),
562 .gso_skb = {
563 .next = (struct sk_buff *)&noop_qdisc.gso_skb,
564 .prev = (struct sk_buff *)&noop_qdisc.gso_skb,
565 .qlen = 0,
566 .lock = __SPIN_LOCK_UNLOCKED(noop_qdisc.gso_skb.lock),
567 },
568 .skb_bad_txq = {
569 .next = (struct sk_buff *)&noop_qdisc.skb_bad_txq,
570 .prev = (struct sk_buff *)&noop_qdisc.skb_bad_txq,
571 .qlen = 0,
572 .lock = __SPIN_LOCK_UNLOCKED(noop_qdisc.skb_bad_txq.lock),
573 },
574};
575EXPORT_SYMBOL(noop_qdisc);
576
577static int noqueue_init(struct Qdisc *qdisc, struct nlattr *opt,
578 struct netlink_ext_ack *extack)
579{
580
581
582
583 qdisc->enqueue = NULL;
584 return 0;
585}
586
587struct Qdisc_ops noqueue_qdisc_ops __read_mostly = {
588 .id = "noqueue",
589 .priv_size = 0,
590 .init = noqueue_init,
591 .enqueue = noop_enqueue,
592 .dequeue = noop_dequeue,
593 .peek = noop_dequeue,
594 .owner = THIS_MODULE,
595};
596
597static const u8 prio2band[TC_PRIO_MAX + 1] = {
598 1, 2, 2, 2, 1, 2, 0, 0 , 1, 1, 1, 1, 1, 1, 1, 1
599};
600
601
602
603
604
605#define PFIFO_FAST_BANDS 3
606
607
608
609
610
611struct pfifo_fast_priv {
612 struct skb_array q[PFIFO_FAST_BANDS];
613};
614
615static inline struct skb_array *band2list(struct pfifo_fast_priv *priv,
616 int band)
617{
618 return &priv->q[band];
619}
620
621static int pfifo_fast_enqueue(struct sk_buff *skb, struct Qdisc *qdisc,
622 struct sk_buff **to_free)
623{
624 int band = prio2band[skb->priority & TC_PRIO_MAX];
625 struct pfifo_fast_priv *priv = qdisc_priv(qdisc);
626 struct skb_array *q = band2list(priv, band);
627 unsigned int pkt_len = qdisc_pkt_len(skb);
628 int err;
629
630 err = skb_array_produce(q, skb);
631
632 if (unlikely(err)) {
633 if (qdisc_is_percpu_stats(qdisc))
634 return qdisc_drop_cpu(skb, qdisc, to_free);
635 else
636 return qdisc_drop(skb, qdisc, to_free);
637 }
638
639 qdisc_update_stats_at_enqueue(qdisc, pkt_len);
640 return NET_XMIT_SUCCESS;
641}
642
643static struct sk_buff *pfifo_fast_dequeue(struct Qdisc *qdisc)
644{
645 struct pfifo_fast_priv *priv = qdisc_priv(qdisc);
646 struct sk_buff *skb = NULL;
647 int band;
648
649 for (band = 0; band < PFIFO_FAST_BANDS && !skb; band++) {
650 struct skb_array *q = band2list(priv, band);
651
652 if (__skb_array_empty(q))
653 continue;
654
655 skb = __skb_array_consume(q);
656 }
657 if (likely(skb)) {
658 qdisc_update_stats_at_dequeue(qdisc, skb);
659 } else {
660 qdisc->empty = true;
661 }
662
663 return skb;
664}
665
666static struct sk_buff *pfifo_fast_peek(struct Qdisc *qdisc)
667{
668 struct pfifo_fast_priv *priv = qdisc_priv(qdisc);
669 struct sk_buff *skb = NULL;
670 int band;
671
672 for (band = 0; band < PFIFO_FAST_BANDS && !skb; band++) {
673 struct skb_array *q = band2list(priv, band);
674
675 skb = __skb_array_peek(q);
676 }
677
678 return skb;
679}
680
681static void pfifo_fast_reset(struct Qdisc *qdisc)
682{
683 int i, band;
684 struct pfifo_fast_priv *priv = qdisc_priv(qdisc);
685
686 for (band = 0; band < PFIFO_FAST_BANDS; band++) {
687 struct skb_array *q = band2list(priv, band);
688 struct sk_buff *skb;
689
690
691
692
693 if (!q->ring.queue)
694 continue;
695
696 while ((skb = __skb_array_consume(q)) != NULL)
697 kfree_skb(skb);
698 }
699
700 if (qdisc_is_percpu_stats(qdisc)) {
701 for_each_possible_cpu(i) {
702 struct gnet_stats_queue *q;
703
704 q = per_cpu_ptr(qdisc->cpu_qstats, i);
705 q->backlog = 0;
706 q->qlen = 0;
707 }
708 }
709}
710
711static int pfifo_fast_dump(struct Qdisc *qdisc, struct sk_buff *skb)
712{
713 struct tc_prio_qopt opt = { .bands = PFIFO_FAST_BANDS };
714
715 memcpy(&opt.priomap, prio2band, TC_PRIO_MAX + 1);
716 if (nla_put(skb, TCA_OPTIONS, sizeof(opt), &opt))
717 goto nla_put_failure;
718 return skb->len;
719
720nla_put_failure:
721 return -1;
722}
723
724static int pfifo_fast_init(struct Qdisc *qdisc, struct nlattr *opt,
725 struct netlink_ext_ack *extack)
726{
727 unsigned int qlen = qdisc_dev(qdisc)->tx_queue_len;
728 struct pfifo_fast_priv *priv = qdisc_priv(qdisc);
729 int prio;
730
731
732 if (!qlen)
733 return -EINVAL;
734
735 for (prio = 0; prio < PFIFO_FAST_BANDS; prio++) {
736 struct skb_array *q = band2list(priv, prio);
737 int err;
738
739 err = skb_array_init(q, qlen, GFP_KERNEL);
740 if (err)
741 return -ENOMEM;
742 }
743
744
745 qdisc->flags |= TCQ_F_CAN_BYPASS;
746 return 0;
747}
748
749static void pfifo_fast_destroy(struct Qdisc *sch)
750{
751 struct pfifo_fast_priv *priv = qdisc_priv(sch);
752 int prio;
753
754 for (prio = 0; prio < PFIFO_FAST_BANDS; prio++) {
755 struct skb_array *q = band2list(priv, prio);
756
757
758
759
760 if (!q->ring.queue)
761 continue;
762
763
764
765 ptr_ring_cleanup(&q->ring, NULL);
766 }
767}
768
769static int pfifo_fast_change_tx_queue_len(struct Qdisc *sch,
770 unsigned int new_len)
771{
772 struct pfifo_fast_priv *priv = qdisc_priv(sch);
773 struct skb_array *bands[PFIFO_FAST_BANDS];
774 int prio;
775
776 for (prio = 0; prio < PFIFO_FAST_BANDS; prio++) {
777 struct skb_array *q = band2list(priv, prio);
778
779 bands[prio] = q;
780 }
781
782 return skb_array_resize_multiple(bands, PFIFO_FAST_BANDS, new_len,
783 GFP_KERNEL);
784}
785
786struct Qdisc_ops pfifo_fast_ops __read_mostly = {
787 .id = "pfifo_fast",
788 .priv_size = sizeof(struct pfifo_fast_priv),
789 .enqueue = pfifo_fast_enqueue,
790 .dequeue = pfifo_fast_dequeue,
791 .peek = pfifo_fast_peek,
792 .init = pfifo_fast_init,
793 .destroy = pfifo_fast_destroy,
794 .reset = pfifo_fast_reset,
795 .dump = pfifo_fast_dump,
796 .change_tx_queue_len = pfifo_fast_change_tx_queue_len,
797 .owner = THIS_MODULE,
798 .static_flags = TCQ_F_NOLOCK | TCQ_F_CPUSTATS,
799};
800EXPORT_SYMBOL(pfifo_fast_ops);
801
802static struct lock_class_key qdisc_tx_busylock;
803static struct lock_class_key qdisc_running_key;
804
805struct Qdisc *qdisc_alloc(struct netdev_queue *dev_queue,
806 const struct Qdisc_ops *ops,
807 struct netlink_ext_ack *extack)
808{
809 void *p;
810 struct Qdisc *sch;
811 unsigned int size = QDISC_ALIGN(sizeof(*sch)) + ops->priv_size;
812 int err = -ENOBUFS;
813 struct net_device *dev;
814
815 if (!dev_queue) {
816 NL_SET_ERR_MSG(extack, "No device queue given");
817 err = -EINVAL;
818 goto errout;
819 }
820
821 dev = dev_queue->dev;
822 p = kzalloc_node(size, GFP_KERNEL,
823 netdev_queue_numa_node_read(dev_queue));
824
825 if (!p)
826 goto errout;
827 sch = (struct Qdisc *) QDISC_ALIGN((unsigned long) p);
828
829 if (sch != p) {
830 kfree(p);
831 p = kzalloc_node(size + QDISC_ALIGNTO - 1, GFP_KERNEL,
832 netdev_queue_numa_node_read(dev_queue));
833 if (!p)
834 goto errout;
835 sch = (struct Qdisc *) QDISC_ALIGN((unsigned long) p);
836 sch->padded = (char *) sch - (char *) p;
837 }
838 __skb_queue_head_init(&sch->gso_skb);
839 __skb_queue_head_init(&sch->skb_bad_txq);
840 qdisc_skb_head_init(&sch->q);
841 spin_lock_init(&sch->q.lock);
842
843 if (ops->static_flags & TCQ_F_CPUSTATS) {
844 sch->cpu_bstats =
845 netdev_alloc_pcpu_stats(struct gnet_stats_basic_cpu);
846 if (!sch->cpu_bstats)
847 goto errout1;
848
849 sch->cpu_qstats = alloc_percpu(struct gnet_stats_queue);
850 if (!sch->cpu_qstats) {
851 free_percpu(sch->cpu_bstats);
852 goto errout1;
853 }
854 }
855
856 spin_lock_init(&sch->busylock);
857 lockdep_set_class(&sch->busylock,
858 dev->qdisc_tx_busylock ?: &qdisc_tx_busylock);
859
860
861 spin_lock_init(&sch->seqlock);
862 lockdep_set_class(&sch->busylock,
863 dev->qdisc_tx_busylock ?: &qdisc_tx_busylock);
864
865 seqcount_init(&sch->running);
866 lockdep_set_class(&sch->running,
867 dev->qdisc_running_key ?: &qdisc_running_key);
868
869 sch->ops = ops;
870 sch->flags = ops->static_flags;
871 sch->enqueue = ops->enqueue;
872 sch->dequeue = ops->dequeue;
873 sch->dev_queue = dev_queue;
874 sch->empty = true;
875 dev_hold(dev);
876 refcount_set(&sch->refcnt, 1);
877
878 return sch;
879errout1:
880 kfree(p);
881errout:
882 return ERR_PTR(err);
883}
884
885struct Qdisc *qdisc_create_dflt(struct netdev_queue *dev_queue,
886 const struct Qdisc_ops *ops,
887 unsigned int parentid,
888 struct netlink_ext_ack *extack)
889{
890 struct Qdisc *sch;
891
892 if (!try_module_get(ops->owner)) {
893 NL_SET_ERR_MSG(extack, "Failed to increase module reference counter");
894 return NULL;
895 }
896
897 sch = qdisc_alloc(dev_queue, ops, extack);
898 if (IS_ERR(sch)) {
899 module_put(ops->owner);
900 return NULL;
901 }
902 sch->parent = parentid;
903
904 if (!ops->init || ops->init(sch, NULL, extack) == 0)
905 return sch;
906
907 qdisc_put(sch);
908 return NULL;
909}
910EXPORT_SYMBOL(qdisc_create_dflt);
911
912
913
914void qdisc_reset(struct Qdisc *qdisc)
915{
916 const struct Qdisc_ops *ops = qdisc->ops;
917 struct sk_buff *skb, *tmp;
918
919 if (ops->reset)
920 ops->reset(qdisc);
921
922 skb_queue_walk_safe(&qdisc->gso_skb, skb, tmp) {
923 __skb_unlink(skb, &qdisc->gso_skb);
924 kfree_skb_list(skb);
925 }
926
927 skb_queue_walk_safe(&qdisc->skb_bad_txq, skb, tmp) {
928 __skb_unlink(skb, &qdisc->skb_bad_txq);
929 kfree_skb_list(skb);
930 }
931
932 qdisc->q.qlen = 0;
933 qdisc->qstats.backlog = 0;
934}
935EXPORT_SYMBOL(qdisc_reset);
936
937void qdisc_free(struct Qdisc *qdisc)
938{
939 if (qdisc_is_percpu_stats(qdisc)) {
940 free_percpu(qdisc->cpu_bstats);
941 free_percpu(qdisc->cpu_qstats);
942 }
943
944 kfree((char *) qdisc - qdisc->padded);
945}
946
947static void qdisc_free_cb(struct rcu_head *head)
948{
949 struct Qdisc *q = container_of(head, struct Qdisc, rcu);
950
951 qdisc_free(q);
952}
953
954static void qdisc_destroy(struct Qdisc *qdisc)
955{
956 const struct Qdisc_ops *ops = qdisc->ops;
957 struct sk_buff *skb, *tmp;
958
959#ifdef CONFIG_NET_SCHED
960 qdisc_hash_del(qdisc);
961
962 qdisc_put_stab(rtnl_dereference(qdisc->stab));
963#endif
964 gen_kill_estimator(&qdisc->rate_est);
965 if (ops->reset)
966 ops->reset(qdisc);
967 if (ops->destroy)
968 ops->destroy(qdisc);
969
970 module_put(ops->owner);
971 dev_put(qdisc_dev(qdisc));
972
973 skb_queue_walk_safe(&qdisc->gso_skb, skb, tmp) {
974 __skb_unlink(skb, &qdisc->gso_skb);
975 kfree_skb_list(skb);
976 }
977
978 skb_queue_walk_safe(&qdisc->skb_bad_txq, skb, tmp) {
979 __skb_unlink(skb, &qdisc->skb_bad_txq);
980 kfree_skb_list(skb);
981 }
982
983 call_rcu(&qdisc->rcu, qdisc_free_cb);
984}
985
986void qdisc_put(struct Qdisc *qdisc)
987{
988 if (qdisc->flags & TCQ_F_BUILTIN ||
989 !refcount_dec_and_test(&qdisc->refcnt))
990 return;
991
992 qdisc_destroy(qdisc);
993}
994EXPORT_SYMBOL(qdisc_put);
995
996
997
998
999
1000
1001void qdisc_put_unlocked(struct Qdisc *qdisc)
1002{
1003 if (qdisc->flags & TCQ_F_BUILTIN ||
1004 !refcount_dec_and_rtnl_lock(&qdisc->refcnt))
1005 return;
1006
1007 qdisc_destroy(qdisc);
1008 rtnl_unlock();
1009}
1010EXPORT_SYMBOL(qdisc_put_unlocked);
1011
1012
1013struct Qdisc *dev_graft_qdisc(struct netdev_queue *dev_queue,
1014 struct Qdisc *qdisc)
1015{
1016 struct Qdisc *oqdisc = dev_queue->qdisc_sleeping;
1017 spinlock_t *root_lock;
1018
1019 root_lock = qdisc_lock(oqdisc);
1020 spin_lock_bh(root_lock);
1021
1022
1023 if (qdisc == NULL)
1024 qdisc = &noop_qdisc;
1025 dev_queue->qdisc_sleeping = qdisc;
1026 rcu_assign_pointer(dev_queue->qdisc, &noop_qdisc);
1027
1028 spin_unlock_bh(root_lock);
1029
1030 return oqdisc;
1031}
1032EXPORT_SYMBOL(dev_graft_qdisc);
1033
1034static void attach_one_default_qdisc(struct net_device *dev,
1035 struct netdev_queue *dev_queue,
1036 void *_unused)
1037{
1038 struct Qdisc *qdisc;
1039 const struct Qdisc_ops *ops = default_qdisc_ops;
1040
1041 if (dev->priv_flags & IFF_NO_QUEUE)
1042 ops = &noqueue_qdisc_ops;
1043
1044 qdisc = qdisc_create_dflt(dev_queue, ops, TC_H_ROOT, NULL);
1045 if (!qdisc) {
1046 netdev_info(dev, "activation failed\n");
1047 return;
1048 }
1049 if (!netif_is_multiqueue(dev))
1050 qdisc->flags |= TCQ_F_ONETXQUEUE | TCQ_F_NOPARENT;
1051 dev_queue->qdisc_sleeping = qdisc;
1052}
1053
1054static void attach_default_qdiscs(struct net_device *dev)
1055{
1056 struct netdev_queue *txq;
1057 struct Qdisc *qdisc;
1058
1059 txq = netdev_get_tx_queue(dev, 0);
1060
1061 if (!netif_is_multiqueue(dev) ||
1062 dev->priv_flags & IFF_NO_QUEUE) {
1063 netdev_for_each_tx_queue(dev, attach_one_default_qdisc, NULL);
1064 dev->qdisc = txq->qdisc_sleeping;
1065 qdisc_refcount_inc(dev->qdisc);
1066 } else {
1067 qdisc = qdisc_create_dflt(txq, &mq_qdisc_ops, TC_H_ROOT, NULL);
1068 if (qdisc) {
1069 dev->qdisc = qdisc;
1070 qdisc->ops->attach(qdisc);
1071 }
1072 }
1073#ifdef CONFIG_NET_SCHED
1074 if (dev->qdisc != &noop_qdisc)
1075 qdisc_hash_add(dev->qdisc, false);
1076#endif
1077}
1078
1079static void transition_one_qdisc(struct net_device *dev,
1080 struct netdev_queue *dev_queue,
1081 void *_need_watchdog)
1082{
1083 struct Qdisc *new_qdisc = dev_queue->qdisc_sleeping;
1084 int *need_watchdog_p = _need_watchdog;
1085
1086 if (!(new_qdisc->flags & TCQ_F_BUILTIN))
1087 clear_bit(__QDISC_STATE_DEACTIVATED, &new_qdisc->state);
1088
1089 rcu_assign_pointer(dev_queue->qdisc, new_qdisc);
1090 if (need_watchdog_p) {
1091 dev_queue->trans_start = 0;
1092 *need_watchdog_p = 1;
1093 }
1094}
1095
1096void dev_activate(struct net_device *dev)
1097{
1098 int need_watchdog;
1099
1100
1101
1102
1103
1104
1105 if (dev->qdisc == &noop_qdisc)
1106 attach_default_qdiscs(dev);
1107
1108 if (!netif_carrier_ok(dev))
1109
1110 return;
1111
1112 need_watchdog = 0;
1113 netdev_for_each_tx_queue(dev, transition_one_qdisc, &need_watchdog);
1114 if (dev_ingress_queue(dev))
1115 transition_one_qdisc(dev, dev_ingress_queue(dev), NULL);
1116
1117 if (need_watchdog) {
1118 netif_trans_update(dev);
1119 dev_watchdog_up(dev);
1120 }
1121}
1122EXPORT_SYMBOL(dev_activate);
1123
1124static void dev_deactivate_queue(struct net_device *dev,
1125 struct netdev_queue *dev_queue,
1126 void *_qdisc_default)
1127{
1128 struct Qdisc *qdisc_default = _qdisc_default;
1129 struct Qdisc *qdisc;
1130
1131 qdisc = rtnl_dereference(dev_queue->qdisc);
1132 if (qdisc) {
1133 bool nolock = qdisc->flags & TCQ_F_NOLOCK;
1134
1135 if (nolock)
1136 spin_lock_bh(&qdisc->seqlock);
1137 spin_lock_bh(qdisc_lock(qdisc));
1138
1139 if (!(qdisc->flags & TCQ_F_BUILTIN))
1140 set_bit(__QDISC_STATE_DEACTIVATED, &qdisc->state);
1141
1142 rcu_assign_pointer(dev_queue->qdisc, qdisc_default);
1143 qdisc_reset(qdisc);
1144
1145 spin_unlock_bh(qdisc_lock(qdisc));
1146 if (nolock)
1147 spin_unlock_bh(&qdisc->seqlock);
1148 }
1149}
1150
1151static bool some_qdisc_is_busy(struct net_device *dev)
1152{
1153 unsigned int i;
1154
1155 for (i = 0; i < dev->num_tx_queues; i++) {
1156 struct netdev_queue *dev_queue;
1157 spinlock_t *root_lock;
1158 struct Qdisc *q;
1159 int val;
1160
1161 dev_queue = netdev_get_tx_queue(dev, i);
1162 q = dev_queue->qdisc_sleeping;
1163
1164 root_lock = qdisc_lock(q);
1165 spin_lock_bh(root_lock);
1166
1167 val = (qdisc_is_running(q) ||
1168 test_bit(__QDISC_STATE_SCHED, &q->state));
1169
1170 spin_unlock_bh(root_lock);
1171
1172 if (val)
1173 return true;
1174 }
1175 return false;
1176}
1177
1178static void dev_qdisc_reset(struct net_device *dev,
1179 struct netdev_queue *dev_queue,
1180 void *none)
1181{
1182 struct Qdisc *qdisc = dev_queue->qdisc_sleeping;
1183
1184 if (qdisc)
1185 qdisc_reset(qdisc);
1186}
1187
1188
1189
1190
1191
1192
1193
1194
1195void dev_deactivate_many(struct list_head *head)
1196{
1197 struct net_device *dev;
1198
1199 list_for_each_entry(dev, head, close_list) {
1200 netdev_for_each_tx_queue(dev, dev_deactivate_queue,
1201 &noop_qdisc);
1202 if (dev_ingress_queue(dev))
1203 dev_deactivate_queue(dev, dev_ingress_queue(dev),
1204 &noop_qdisc);
1205
1206 dev_watchdog_down(dev);
1207 }
1208
1209
1210
1211
1212
1213 synchronize_net();
1214
1215
1216 list_for_each_entry(dev, head, close_list) {
1217 while (some_qdisc_is_busy(dev))
1218 yield();
1219
1220
1221
1222 netdev_for_each_tx_queue(dev, dev_qdisc_reset, NULL);
1223 if (dev_ingress_queue(dev))
1224 dev_qdisc_reset(dev, dev_ingress_queue(dev), NULL);
1225 }
1226}
1227
1228void dev_deactivate(struct net_device *dev)
1229{
1230 LIST_HEAD(single);
1231
1232 list_add(&dev->close_list, &single);
1233 dev_deactivate_many(&single);
1234 list_del(&single);
1235}
1236EXPORT_SYMBOL(dev_deactivate);
1237
1238static int qdisc_change_tx_queue_len(struct net_device *dev,
1239 struct netdev_queue *dev_queue)
1240{
1241 struct Qdisc *qdisc = dev_queue->qdisc_sleeping;
1242 const struct Qdisc_ops *ops = qdisc->ops;
1243
1244 if (ops->change_tx_queue_len)
1245 return ops->change_tx_queue_len(qdisc, dev->tx_queue_len);
1246 return 0;
1247}
1248
1249int dev_qdisc_change_tx_queue_len(struct net_device *dev)
1250{
1251 bool up = dev->flags & IFF_UP;
1252 unsigned int i;
1253 int ret = 0;
1254
1255 if (up)
1256 dev_deactivate(dev);
1257
1258 for (i = 0; i < dev->num_tx_queues; i++) {
1259 ret = qdisc_change_tx_queue_len(dev, &dev->_tx[i]);
1260
1261
1262 if (ret)
1263 break;
1264 }
1265
1266 if (up)
1267 dev_activate(dev);
1268 return ret;
1269}
1270
1271static void dev_init_scheduler_queue(struct net_device *dev,
1272 struct netdev_queue *dev_queue,
1273 void *_qdisc)
1274{
1275 struct Qdisc *qdisc = _qdisc;
1276
1277 rcu_assign_pointer(dev_queue->qdisc, qdisc);
1278 dev_queue->qdisc_sleeping = qdisc;
1279}
1280
1281void dev_init_scheduler(struct net_device *dev)
1282{
1283 dev->qdisc = &noop_qdisc;
1284 netdev_for_each_tx_queue(dev, dev_init_scheduler_queue, &noop_qdisc);
1285 if (dev_ingress_queue(dev))
1286 dev_init_scheduler_queue(dev, dev_ingress_queue(dev), &noop_qdisc);
1287
1288 timer_setup(&dev->watchdog_timer, dev_watchdog, 0);
1289}
1290
1291static void shutdown_scheduler_queue(struct net_device *dev,
1292 struct netdev_queue *dev_queue,
1293 void *_qdisc_default)
1294{
1295 struct Qdisc *qdisc = dev_queue->qdisc_sleeping;
1296 struct Qdisc *qdisc_default = _qdisc_default;
1297
1298 if (qdisc) {
1299 rcu_assign_pointer(dev_queue->qdisc, qdisc_default);
1300 dev_queue->qdisc_sleeping = qdisc_default;
1301
1302 qdisc_put(qdisc);
1303 }
1304}
1305
1306void dev_shutdown(struct net_device *dev)
1307{
1308 netdev_for_each_tx_queue(dev, shutdown_scheduler_queue, &noop_qdisc);
1309 if (dev_ingress_queue(dev))
1310 shutdown_scheduler_queue(dev, dev_ingress_queue(dev), &noop_qdisc);
1311 qdisc_put(dev->qdisc);
1312 dev->qdisc = &noop_qdisc;
1313
1314 WARN_ON(timer_pending(&dev->watchdog_timer));
1315}
1316
1317void psched_ratecfg_precompute(struct psched_ratecfg *r,
1318 const struct tc_ratespec *conf,
1319 u64 rate64)
1320{
1321 memset(r, 0, sizeof(*r));
1322 r->overhead = conf->overhead;
1323 r->rate_bytes_ps = max_t(u64, conf->rate, rate64);
1324 r->linklayer = (conf->linklayer & TC_LINKLAYER_MASK);
1325 r->mult = 1;
1326
1327
1328
1329
1330
1331
1332
1333
1334
1335
1336
1337
1338
1339 if (r->rate_bytes_ps > 0) {
1340 u64 factor = NSEC_PER_SEC;
1341
1342 for (;;) {
1343 r->mult = div64_u64(factor, r->rate_bytes_ps);
1344 if (r->mult & (1U << 31) || factor & (1ULL << 63))
1345 break;
1346 factor <<= 1;
1347 r->shift++;
1348 }
1349 }
1350}
1351EXPORT_SYMBOL(psched_ratecfg_precompute);
1352
1353static void mini_qdisc_rcu_func(struct rcu_head *head)
1354{
1355}
1356
1357void mini_qdisc_pair_swap(struct mini_Qdisc_pair *miniqp,
1358 struct tcf_proto *tp_head)
1359{
1360
1361
1362
1363 struct mini_Qdisc *miniq_old =
1364 rcu_dereference_protected(*miniqp->p_miniq, 1);
1365 struct mini_Qdisc *miniq;
1366
1367 if (!tp_head) {
1368 RCU_INIT_POINTER(*miniqp->p_miniq, NULL);
1369
1370 rcu_barrier();
1371 return;
1372 }
1373
1374 miniq = !miniq_old || miniq_old == &miniqp->miniq2 ?
1375 &miniqp->miniq1 : &miniqp->miniq2;
1376
1377
1378
1379
1380
1381 rcu_barrier();
1382 miniq->filter_list = tp_head;
1383 rcu_assign_pointer(*miniqp->p_miniq, miniq);
1384
1385 if (miniq_old)
1386
1387
1388
1389
1390 call_rcu(&miniq_old->rcu, mini_qdisc_rcu_func);
1391}
1392EXPORT_SYMBOL(mini_qdisc_pair_swap);
1393
1394void mini_qdisc_pair_init(struct mini_Qdisc_pair *miniqp, struct Qdisc *qdisc,
1395 struct mini_Qdisc __rcu **p_miniq)
1396{
1397 miniqp->miniq1.cpu_bstats = qdisc->cpu_bstats;
1398 miniqp->miniq1.cpu_qstats = qdisc->cpu_qstats;
1399 miniqp->miniq2.cpu_bstats = qdisc->cpu_bstats;
1400 miniqp->miniq2.cpu_qstats = qdisc->cpu_qstats;
1401 miniqp->p_miniq = p_miniq;
1402}
1403EXPORT_SYMBOL(mini_qdisc_pair_init);
1404