1// SPDX-License-Identifier: GPL-2.0-or-later
2/*
3 * net/sched/sch_gred.c Generic Random Early Detection queue.
4 *
5 * Authors: J Hadi Salim (hadi@cyberus.ca) 1998-2002
6 *
7 * 991129: - Bug fix with grio mode
8 * - a better sing. AvgQ mode with Grio(WRED)
9 * - A finer grained VQ dequeue based on suggestion
10 * from Ren Liu
11 * - More error checks
12 *
13 * For all the glorious comments look at include/net/red.h
14 */
15
16#include <linux/slab.h>
17#include <linux/module.h>
18#include <linux/types.h>
19#include <linux/kernel.h>
20#include <linux/skbuff.h>
21#include <net/pkt_cls.h>
22#include <net/pkt_sched.h>
23#include <net/red.h>
24
25#define GRED_DEF_PRIO (MAX_DPs / 2)
26#define GRED_VQ_MASK (MAX_DPs - 1)
27
28#define GRED_VQ_RED_FLAGS (TC_RED_ECN | TC_RED_HARDDROP)
29
30struct gred_sched_data;
31struct gred_sched;
32
33struct gred_sched_data {
34 u32 limit; /* HARD maximal queue length */
35 u32 DP; /* the drop parameters */
36 u32 red_flags; /* virtualQ version of red_flags */
37 u64 bytesin; /* bytes seen on virtualQ so far*/
38 u32 packetsin; /* packets seen on virtualQ so far*/
39 u32 backlog; /* bytes on the virtualQ */
40 u8 prio; /* the prio of this vq */
41
42 struct red_parms parms;
43 struct red_vars vars;
44 struct red_stats stats;
45};
46
47enum {
48 GRED_WRED_MODE = 1,
49 GRED_RIO_MODE,
50};
51
52struct gred_sched {
53 struct gred_sched_data *tab[MAX_DPs];
54 unsigned long flags;
55 u32 red_flags;
56 u32 DPs;
57 u32 def;
58 struct red_vars wred_set;
59 struct tc_gred_qopt_offload *opt;
60};
61
62static inline int gred_wred_mode(struct gred_sched *table)
63{
64 return test_bit(GRED_WRED_MODE, &table->flags);
65}
66
67static inline void gred_enable_wred_mode(struct gred_sched *table)
68{
69 __set_bit(GRED_WRED_MODE, &table->flags);
70}
71
72static inline void gred_disable_wred_mode(struct gred_sched *table)
73{
74 __clear_bit(GRED_WRED_MODE, &table->flags);
75}
76
77static inline int gred_rio_mode(struct gred_sched *table)
78{
79 return test_bit(GRED_RIO_MODE, &table->flags);
80}
81
82static inline void gred_enable_rio_mode(struct gred_sched *table)
83{
84 __set_bit(GRED_RIO_MODE, &table->flags);
85}
86
87static inline void gred_disable_rio_mode(struct gred_sched *table)
88{
89 __clear_bit(GRED_RIO_MODE, &table->flags);
90}
91
92static inline int gred_wred_mode_check(struct Qdisc *sch)
93{
94 struct gred_sched *table = qdisc_priv(sch);
95 int i;
96
97 /* Really ugly O(n^2) but shouldn't be necessary too frequent. */
98 for (i = 0; i < table->DPs; i++) {
99 struct gred_sched_data *q = table->tab[i];
100 int n;
101
102 if (q == NULL)
103 continue;
104
105 for (n = i + 1; n < table->DPs; n++)
106 if (table->tab[n] && table->tab[n]->prio == q->prio)
107 return 1;
108 }
109
110 return 0;
111}
112
113static inline unsigned int gred_backlog(struct gred_sched *table,
114 struct gred_sched_data *q,
115 struct Qdisc *sch)
116{
117 if (gred_wred_mode(table))
118 return sch->qstats.backlog;
119 else
120 return q->backlog;
121}
122
123static inline u16 tc_index_to_dp(struct sk_buff *skb)
124{
125 return skb->tc_index & GRED_VQ_MASK;
126}
127
128static inline void gred_load_wred_set(const struct gred_sched *table,
129 struct gred_sched_data *q)
130{
131 q->vars.qavg = table->wred_set.qavg;
132 q->vars.qidlestart = table->wred_set.qidlestart;
133}
134
135static inline void gred_store_wred_set(struct gred_sched *table,
136 struct gred_sched_data *q)
137{
138 table->wred_set.qavg = q->vars.qavg;
139 table->wred_set.qidlestart = q->vars.qidlestart;
140}
141
142static int gred_use_ecn(struct gred_sched_data *q)
143{
144 return q->red_flags & TC_RED_ECN;
145}
146
147static int gred_use_harddrop(struct gred_sched_data *q)
148{
149 return q->red_flags & TC_RED_HARDDROP;
150}
151
152static bool gred_per_vq_red_flags_used(struct gred_sched *table)
153{
154 unsigned int i;
155
156 /* Local per-vq flags couldn't have been set unless global are 0 */
157 if (table->red_flags)
158 return false;
159 for (i = 0; i < MAX_DPs; i++)
160 if (table->tab[i] && table->tab[i]->red_flags)
161 return true;
162 return false;
163}
164
165static int gred_enqueue(struct sk_buff *skb, struct Qdisc *sch,
166 struct sk_buff **to_free)
167{
168 struct gred_sched_data *q = NULL;
169 struct gred_sched *t = qdisc_priv(sch);
170 unsigned long qavg = 0;
171 u16 dp = tc_index_to_dp(skb);
172
173 if (dp >= t->DPs || (q = t->tab[dp]) == NULL) {
174 dp = t->def;
175
176 q = t->tab[dp];
177 if (!q) {
178 /* Pass through packets not assigned to a DP
179 * if no default DP has been configured. This
180 * allows for DP flows to be left untouched.
181 */
182 if (likely(sch->qstats.backlog + qdisc_pkt_len(skb) <=
183 sch->limit))
184 return qdisc_enqueue_tail(skb, sch);
185 else
186 goto drop;
187 }
188
189 /* fix tc_index? --could be controversial but needed for
190 requeueing */
191 skb->tc_index = (skb->tc_index & ~GRED_VQ_MASK) | dp;
192 }
193
194 /* sum up all the qaves of prios < ours to get the new qave */
195 if (!gred_wred_mode(table: t) && gred_rio_mode(table: t)) {
196 int i;
197
198 for (i = 0; i < t->DPs; i++) {
199 if (t->tab[i] && t->tab[i]->prio < q->prio &&
200 !red_is_idling(v: &t->tab[i]->vars))
201 qavg += t->tab[i]->vars.qavg;
202 }
203
204 }
205
206 q->packetsin++;
207 q->bytesin += qdisc_pkt_len(skb);
208
209 if (gred_wred_mode(table: t))
210 gred_load_wred_set(table: t, q);
211
212 q->vars.qavg = red_calc_qavg(p: &q->parms,
213 v: &q->vars,
214 backlog: gred_backlog(table: t, q, sch));
215
216 if (red_is_idling(v: &q->vars))
217 red_end_of_idle_period(v: &q->vars);
218
219 if (gred_wred_mode(table: t))
220 gred_store_wred_set(table: t, q);
221
222 switch (red_action(p: &q->parms, v: &q->vars, qavg: q->vars.qavg + qavg)) {
223 case RED_DONT_MARK:
224 break;
225
226 case RED_PROB_MARK:
227 qdisc_qstats_overlimit(sch);
228 if (!gred_use_ecn(q) || !INET_ECN_set_ce(skb)) {
229 q->stats.prob_drop++;
230 goto congestion_drop;
231 }
232
233 q->stats.prob_mark++;
234 break;
235
236 case RED_HARD_MARK:
237 qdisc_qstats_overlimit(sch);
238 if (gred_use_harddrop(q) || !gred_use_ecn(q) ||
239 !INET_ECN_set_ce(skb)) {
240 q->stats.forced_drop++;
241 goto congestion_drop;
242 }
243 q->stats.forced_mark++;
244 break;
245 }
246
247 if (gred_backlog(table: t, q, sch) + qdisc_pkt_len(skb) <= q->limit) {
248 q->backlog += qdisc_pkt_len(skb);
249 return qdisc_enqueue_tail(skb, sch);
250 }
251
252 q->stats.pdrop++;
253drop:
254 return qdisc_drop(skb, sch, to_free);
255
256congestion_drop:
257 qdisc_drop(skb, sch, to_free);
258 return NET_XMIT_CN;
259}
260
261static struct sk_buff *gred_dequeue(struct Qdisc *sch)
262{
263 struct sk_buff *skb;
264 struct gred_sched *t = qdisc_priv(sch);
265
266 skb = qdisc_dequeue_head(sch);
267
268 if (skb) {
269 struct gred_sched_data *q;
270 u16 dp = tc_index_to_dp(skb);
271
272 if (dp >= t->DPs || (q = t->tab[dp]) == NULL) {
273 net_warn_ratelimited("GRED: Unable to relocate VQ 0x%x after dequeue, screwing up backlog\n",
274 tc_index_to_dp(skb));
275 } else {
276 q->backlog -= qdisc_pkt_len(skb);
277
278 if (gred_wred_mode(table: t)) {
279 if (!sch->qstats.backlog)
280 red_start_of_idle_period(v: &t->wred_set);
281 } else {
282 if (!q->backlog)
283 red_start_of_idle_period(v: &q->vars);
284 }
285 }
286
287 return skb;
288 }
289
290 return NULL;
291}
292
293static void gred_reset(struct Qdisc *sch)
294{
295 int i;
296 struct gred_sched *t = qdisc_priv(sch);
297
298 qdisc_reset_queue(sch);
299
300 for (i = 0; i < t->DPs; i++) {
301 struct gred_sched_data *q = t->tab[i];
302
303 if (!q)
304 continue;
305
306 red_restart(v: &q->vars);
307 q->backlog = 0;
308 }
309}
310
311static void gred_offload(struct Qdisc *sch, enum tc_gred_command command)
312{
313 struct gred_sched *table = qdisc_priv(sch);
314 struct net_device *dev = qdisc_dev(qdisc: sch);
315 struct tc_gred_qopt_offload *opt = table->opt;
316
317 if (!tc_can_offload(dev) || !dev->netdev_ops->ndo_setup_tc)
318 return;
319
320 memset(opt, 0, sizeof(*opt));
321 opt->command = command;
322 opt->handle = sch->handle;
323 opt->parent = sch->parent;
324
325 if (command == TC_GRED_REPLACE) {
326 unsigned int i;
327
328 opt->set.grio_on = gred_rio_mode(table);
329 opt->set.wred_on = gred_wred_mode(table);
330 opt->set.dp_cnt = table->DPs;
331 opt->set.dp_def = table->def;
332
333 for (i = 0; i < table->DPs; i++) {
334 struct gred_sched_data *q = table->tab[i];
335
336 if (!q)
337 continue;
338 opt->set.tab[i].present = true;
339 opt->set.tab[i].limit = q->limit;
340 opt->set.tab[i].prio = q->prio;
341 opt->set.tab[i].min = q->parms.qth_min >> q->parms.Wlog;
342 opt->set.tab[i].max = q->parms.qth_max >> q->parms.Wlog;
343 opt->set.tab[i].is_ecn = gred_use_ecn(q);
344 opt->set.tab[i].is_harddrop = gred_use_harddrop(q);
345 opt->set.tab[i].probability = q->parms.max_P;
346 opt->set.tab[i].backlog = &q->backlog;
347 }
348 opt->set.qstats = &sch->qstats;
349 }
350
351 dev->netdev_ops->ndo_setup_tc(dev, TC_SETUP_QDISC_GRED, opt);
352}
353
354static int gred_offload_dump_stats(struct Qdisc *sch)
355{
356 struct gred_sched *table = qdisc_priv(sch);
357 struct tc_gred_qopt_offload *hw_stats;
358 u64 bytes = 0, packets = 0;
359 unsigned int i;
360 int ret;
361
362 hw_stats = kzalloc(size: sizeof(*hw_stats), GFP_KERNEL);
363 if (!hw_stats)
364 return -ENOMEM;
365
366 hw_stats->command = TC_GRED_STATS;
367 hw_stats->handle = sch->handle;
368 hw_stats->parent = sch->parent;
369
370 for (i = 0; i < MAX_DPs; i++) {
371 gnet_stats_basic_sync_init(b: &hw_stats->stats.bstats[i]);
372 if (table->tab[i])
373 hw_stats->stats.xstats[i] = &table->tab[i]->stats;
374 }
375
376 ret = qdisc_offload_dump_helper(q: sch, type: TC_SETUP_QDISC_GRED, type_data: hw_stats);
377 /* Even if driver returns failure adjust the stats - in case offload
378 * ended but driver still wants to adjust the values.
379 */
380 sch_tree_lock(q: sch);
381 for (i = 0; i < MAX_DPs; i++) {
382 if (!table->tab[i])
383 continue;
384 table->tab[i]->packetsin += u64_stats_read(p: &hw_stats->stats.bstats[i].packets);
385 table->tab[i]->bytesin += u64_stats_read(p: &hw_stats->stats.bstats[i].bytes);
386 table->tab[i]->backlog += hw_stats->stats.qstats[i].backlog;
387
388 bytes += u64_stats_read(p: &hw_stats->stats.bstats[i].bytes);
389 packets += u64_stats_read(p: &hw_stats->stats.bstats[i].packets);
390 sch->qstats.qlen += hw_stats->stats.qstats[i].qlen;
391 sch->qstats.backlog += hw_stats->stats.qstats[i].backlog;
392 sch->qstats.drops += hw_stats->stats.qstats[i].drops;
393 sch->qstats.requeues += hw_stats->stats.qstats[i].requeues;
394 sch->qstats.overlimits += hw_stats->stats.qstats[i].overlimits;
395 }
396 _bstats_update(bstats: &sch->bstats, bytes, packets);
397 sch_tree_unlock(q: sch);
398
399 kfree(objp: hw_stats);
400 return ret;
401}
402
403static inline void gred_destroy_vq(struct gred_sched_data *q)
404{
405 kfree(objp: q);
406}
407
408static int gred_change_table_def(struct Qdisc *sch, struct nlattr *dps,
409 struct netlink_ext_ack *extack)
410{
411 struct gred_sched *table = qdisc_priv(sch);
412 struct tc_gred_sopt *sopt;
413 bool red_flags_changed;
414 int i;
415
416 if (!dps)
417 return -EINVAL;
418
419 sopt = nla_data(nla: dps);
420
421 if (sopt->DPs > MAX_DPs) {
422 NL_SET_ERR_MSG_MOD(extack, "number of virtual queues too high");
423 return -EINVAL;
424 }
425 if (sopt->DPs == 0) {
426 NL_SET_ERR_MSG_MOD(extack,
427 "number of virtual queues can't be 0");
428 return -EINVAL;
429 }
430 if (sopt->def_DP >= sopt->DPs) {
431 NL_SET_ERR_MSG_MOD(extack, "default virtual queue above virtual queue count");
432 return -EINVAL;
433 }
434 if (sopt->flags && gred_per_vq_red_flags_used(table)) {
435 NL_SET_ERR_MSG_MOD(extack, "can't set per-Qdisc RED flags when per-virtual queue flags are used");
436 return -EINVAL;
437 }
438
439 sch_tree_lock(q: sch);
440 table->DPs = sopt->DPs;
441 table->def = sopt->def_DP;
442 red_flags_changed = table->red_flags != sopt->flags;
443 table->red_flags = sopt->flags;
444
445 /*
446 * Every entry point to GRED is synchronized with the above code
447 * and the DP is checked against DPs, i.e. shadowed VQs can no
448 * longer be found so we can unlock right here.
449 */
450 sch_tree_unlock(q: sch);
451
452 if (sopt->grio) {
453 gred_enable_rio_mode(table);
454 gred_disable_wred_mode(table);
455 if (gred_wred_mode_check(sch))
456 gred_enable_wred_mode(table);
457 } else {
458 gred_disable_rio_mode(table);
459 gred_disable_wred_mode(table);
460 }
461
462 if (red_flags_changed)
463 for (i = 0; i < table->DPs; i++)
464 if (table->tab[i])
465 table->tab[i]->red_flags =
466 table->red_flags & GRED_VQ_RED_FLAGS;
467
468 for (i = table->DPs; i < MAX_DPs; i++) {
469 if (table->tab[i]) {
470 pr_warn("GRED: Warning: Destroying shadowed VQ 0x%x\n",
471 i);
472 gred_destroy_vq(q: table->tab[i]);
473 table->tab[i] = NULL;
474 }
475 }
476
477 gred_offload(sch, command: TC_GRED_REPLACE);
478 return 0;
479}
480
481static inline int gred_change_vq(struct Qdisc *sch, int dp,
482 struct tc_gred_qopt *ctl, int prio,
483 u8 *stab, u32 max_P,
484 struct gred_sched_data **prealloc,
485 struct netlink_ext_ack *extack)
486{
487 struct gred_sched *table = qdisc_priv(sch);
488 struct gred_sched_data *q = table->tab[dp];
489
490 if (!red_check_params(qth_min: ctl->qth_min, qth_max: ctl->qth_max, Wlog: ctl->Wlog, Scell_log: ctl->Scell_log, stab)) {
491 NL_SET_ERR_MSG_MOD(extack, "invalid RED parameters");
492 return -EINVAL;
493 }
494
495 if (!q) {
496 table->tab[dp] = q = *prealloc;
497 *prealloc = NULL;
498 if (!q)
499 return -ENOMEM;
500 q->red_flags = table->red_flags & GRED_VQ_RED_FLAGS;
501 }
502
503 q->DP = dp;
504 q->prio = prio;
505 if (ctl->limit > sch->limit)
506 q->limit = sch->limit;
507 else
508 q->limit = ctl->limit;
509
510 if (q->backlog == 0)
511 red_end_of_idle_period(v: &q->vars);
512
513 red_set_parms(p: &q->parms,
514 qth_min: ctl->qth_min, qth_max: ctl->qth_max, Wlog: ctl->Wlog, Plog: ctl->Plog,
515 Scell_log: ctl->Scell_log, stab, max_P);
516 red_set_vars(v: &q->vars);
517 return 0;
518}
519
520static const struct nla_policy gred_vq_policy[TCA_GRED_VQ_MAX + 1] = {
521 [TCA_GRED_VQ_DP] = { .type = NLA_U32 },
522 [TCA_GRED_VQ_FLAGS] = { .type = NLA_U32 },
523};
524
525static const struct nla_policy gred_vqe_policy[TCA_GRED_VQ_ENTRY_MAX + 1] = {
526 [TCA_GRED_VQ_ENTRY] = { .type = NLA_NESTED },
527};
528
529static const struct nla_policy gred_policy[TCA_GRED_MAX + 1] = {
530 [TCA_GRED_PARMS] = { .len = sizeof(struct tc_gred_qopt) },
531 [TCA_GRED_STAB] = { .len = 256 },
532 [TCA_GRED_DPS] = { .len = sizeof(struct tc_gred_sopt) },
533 [TCA_GRED_MAX_P] = { .type = NLA_U32 },
534 [TCA_GRED_LIMIT] = { .type = NLA_U32 },
535 [TCA_GRED_VQ_LIST] = { .type = NLA_NESTED },
536};
537
538static void gred_vq_apply(struct gred_sched *table, const struct nlattr *entry)
539{
540 struct nlattr *tb[TCA_GRED_VQ_MAX + 1];
541 u32 dp;
542
543 nla_parse_nested_deprecated(tb, TCA_GRED_VQ_MAX, nla: entry,
544 policy: gred_vq_policy, NULL);
545
546 dp = nla_get_u32(nla: tb[TCA_GRED_VQ_DP]);
547
548 if (tb[TCA_GRED_VQ_FLAGS])
549 table->tab[dp]->red_flags = nla_get_u32(nla: tb[TCA_GRED_VQ_FLAGS]);
550}
551
552static void gred_vqs_apply(struct gred_sched *table, struct nlattr *vqs)
553{
554 const struct nlattr *attr;
555 int rem;
556
557 nla_for_each_nested(attr, vqs, rem) {
558 switch (nla_type(nla: attr)) {
559 case TCA_GRED_VQ_ENTRY:
560 gred_vq_apply(table, entry: attr);
561 break;
562 }
563 }
564}
565
566static int gred_vq_validate(struct gred_sched *table, u32 cdp,
567 const struct nlattr *entry,
568 struct netlink_ext_ack *extack)
569{
570 struct nlattr *tb[TCA_GRED_VQ_MAX + 1];
571 int err;
572 u32 dp;
573
574 err = nla_parse_nested_deprecated(tb, TCA_GRED_VQ_MAX, nla: entry,
575 policy: gred_vq_policy, extack);
576 if (err < 0)
577 return err;
578
579 if (!tb[TCA_GRED_VQ_DP]) {
580 NL_SET_ERR_MSG_MOD(extack, "Virtual queue with no index specified");
581 return -EINVAL;
582 }
583 dp = nla_get_u32(nla: tb[TCA_GRED_VQ_DP]);
584 if (dp >= table->DPs) {
585 NL_SET_ERR_MSG_MOD(extack, "Virtual queue with index out of bounds");
586 return -EINVAL;
587 }
588 if (dp != cdp && !table->tab[dp]) {
589 NL_SET_ERR_MSG_MOD(extack, "Virtual queue not yet instantiated");
590 return -EINVAL;
591 }
592
593 if (tb[TCA_GRED_VQ_FLAGS]) {
594 u32 red_flags = nla_get_u32(nla: tb[TCA_GRED_VQ_FLAGS]);
595
596 if (table->red_flags && table->red_flags != red_flags) {
597 NL_SET_ERR_MSG_MOD(extack, "can't change per-virtual queue RED flags when per-Qdisc flags are used");
598 return -EINVAL;
599 }
600 if (red_flags & ~GRED_VQ_RED_FLAGS) {
601 NL_SET_ERR_MSG_MOD(extack,
602 "invalid RED flags specified");
603 return -EINVAL;
604 }
605 }
606
607 return 0;
608}
609
610static int gred_vqs_validate(struct gred_sched *table, u32 cdp,
611 struct nlattr *vqs, struct netlink_ext_ack *extack)
612{
613 const struct nlattr *attr;
614 int rem, err;
615
616 err = nla_validate_nested_deprecated(start: vqs, TCA_GRED_VQ_ENTRY_MAX,
617 policy: gred_vqe_policy, extack);
618 if (err < 0)
619 return err;
620
621 nla_for_each_nested(attr, vqs, rem) {
622 switch (nla_type(nla: attr)) {
623 case TCA_GRED_VQ_ENTRY:
624 err = gred_vq_validate(table, cdp, entry: attr, extack);
625 if (err)
626 return err;
627 break;
628 default:
629 NL_SET_ERR_MSG_MOD(extack, "GRED_VQ_LIST can contain only entry attributes");
630 return -EINVAL;
631 }
632 }
633
634 if (rem > 0) {
635 NL_SET_ERR_MSG_MOD(extack, "Trailing data after parsing virtual queue list");
636 return -EINVAL;
637 }
638
639 return 0;
640}
641
642static int gred_change(struct Qdisc *sch, struct nlattr *opt,
643 struct netlink_ext_ack *extack)
644{
645 struct gred_sched *table = qdisc_priv(sch);
646 struct tc_gred_qopt *ctl;
647 struct nlattr *tb[TCA_GRED_MAX + 1];
648 int err, prio = GRED_DEF_PRIO;
649 u8 *stab;
650 u32 max_P;
651 struct gred_sched_data *prealloc;
652
653 err = nla_parse_nested_deprecated(tb, TCA_GRED_MAX, nla: opt, policy: gred_policy,
654 extack);
655 if (err < 0)
656 return err;
657
658 if (tb[TCA_GRED_PARMS] == NULL && tb[TCA_GRED_STAB] == NULL) {
659 if (tb[TCA_GRED_LIMIT] != NULL)
660 sch->limit = nla_get_u32(nla: tb[TCA_GRED_LIMIT]);
661 return gred_change_table_def(sch, dps: tb[TCA_GRED_DPS], extack);
662 }
663
664 if (tb[TCA_GRED_PARMS] == NULL ||
665 tb[TCA_GRED_STAB] == NULL ||
666 tb[TCA_GRED_LIMIT] != NULL) {
667 NL_SET_ERR_MSG_MOD(extack, "can't configure Qdisc and virtual queue at the same time");
668 return -EINVAL;
669 }
670
671 max_P = tb[TCA_GRED_MAX_P] ? nla_get_u32(nla: tb[TCA_GRED_MAX_P]) : 0;
672
673 ctl = nla_data(nla: tb[TCA_GRED_PARMS]);
674 stab = nla_data(nla: tb[TCA_GRED_STAB]);
675
676 if (ctl->DP >= table->DPs) {
677 NL_SET_ERR_MSG_MOD(extack, "virtual queue index above virtual queue count");
678 return -EINVAL;
679 }
680
681 if (tb[TCA_GRED_VQ_LIST]) {
682 err = gred_vqs_validate(table, cdp: ctl->DP, vqs: tb[TCA_GRED_VQ_LIST],
683 extack);
684 if (err)
685 return err;
686 }
687
688 if (gred_rio_mode(table)) {
689 if (ctl->prio == 0) {
690 int def_prio = GRED_DEF_PRIO;
691
692 if (table->tab[table->def])
693 def_prio = table->tab[table->def]->prio;
694
695 printk(KERN_DEBUG "GRED: DP %u does not have a prio "
696 "setting default to %d\n", ctl->DP, def_prio);
697
698 prio = def_prio;
699 } else
700 prio = ctl->prio;
701 }
702
703 prealloc = kzalloc(size: sizeof(*prealloc), GFP_KERNEL);
704 sch_tree_lock(q: sch);
705
706 err = gred_change_vq(sch, dp: ctl->DP, ctl, prio, stab, max_P, prealloc: &prealloc,
707 extack);
708 if (err < 0)
709 goto err_unlock_free;
710
711 if (tb[TCA_GRED_VQ_LIST])
712 gred_vqs_apply(table, vqs: tb[TCA_GRED_VQ_LIST]);
713
714 if (gred_rio_mode(table)) {
715 gred_disable_wred_mode(table);
716 if (gred_wred_mode_check(sch))
717 gred_enable_wred_mode(table);
718 }
719
720 sch_tree_unlock(q: sch);
721 kfree(objp: prealloc);
722
723 gred_offload(sch, command: TC_GRED_REPLACE);
724 return 0;
725
726err_unlock_free:
727 sch_tree_unlock(q: sch);
728 kfree(objp: prealloc);
729 return err;
730}
731
732static int gred_init(struct Qdisc *sch, struct nlattr *opt,
733 struct netlink_ext_ack *extack)
734{
735 struct gred_sched *table = qdisc_priv(sch);
736 struct nlattr *tb[TCA_GRED_MAX + 1];
737 int err;
738
739 if (!opt)
740 return -EINVAL;
741
742 err = nla_parse_nested_deprecated(tb, TCA_GRED_MAX, nla: opt, policy: gred_policy,
743 extack);
744 if (err < 0)
745 return err;
746
747 if (tb[TCA_GRED_PARMS] || tb[TCA_GRED_STAB]) {
748 NL_SET_ERR_MSG_MOD(extack,
749 "virtual queue configuration can't be specified at initialization time");
750 return -EINVAL;
751 }
752
753 if (tb[TCA_GRED_LIMIT])
754 sch->limit = nla_get_u32(nla: tb[TCA_GRED_LIMIT]);
755 else
756 sch->limit = qdisc_dev(qdisc: sch)->tx_queue_len
757 * psched_mtu(dev: qdisc_dev(qdisc: sch));
758
759 if (qdisc_dev(qdisc: sch)->netdev_ops->ndo_setup_tc) {
760 table->opt = kzalloc(size: sizeof(*table->opt), GFP_KERNEL);
761 if (!table->opt)
762 return -ENOMEM;
763 }
764
765 return gred_change_table_def(sch, dps: tb[TCA_GRED_DPS], extack);
766}
767
768static int gred_dump(struct Qdisc *sch, struct sk_buff *skb)
769{
770 struct gred_sched *table = qdisc_priv(sch);
771 struct nlattr *parms, *vqs, *opts = NULL;
772 int i;
773 u32 max_p[MAX_DPs];
774 struct tc_gred_sopt sopt = {
775 .DPs = table->DPs,
776 .def_DP = table->def,
777 .grio = gred_rio_mode(table),
778 .flags = table->red_flags,
779 };
780
781 if (gred_offload_dump_stats(sch))
782 goto nla_put_failure;
783
784 opts = nla_nest_start_noflag(skb, attrtype: TCA_OPTIONS);
785 if (opts == NULL)
786 goto nla_put_failure;
787 if (nla_put(skb, attrtype: TCA_GRED_DPS, attrlen: sizeof(sopt), data: &sopt))
788 goto nla_put_failure;
789
790 for (i = 0; i < MAX_DPs; i++) {
791 struct gred_sched_data *q = table->tab[i];
792
793 max_p[i] = q ? q->parms.max_P : 0;
794 }
795 if (nla_put(skb, attrtype: TCA_GRED_MAX_P, attrlen: sizeof(max_p), data: max_p))
796 goto nla_put_failure;
797
798 if (nla_put_u32(skb, attrtype: TCA_GRED_LIMIT, value: sch->limit))
799 goto nla_put_failure;
800
801 /* Old style all-in-one dump of VQs */
802 parms = nla_nest_start_noflag(skb, attrtype: TCA_GRED_PARMS);
803 if (parms == NULL)
804 goto nla_put_failure;
805
806 for (i = 0; i < MAX_DPs; i++) {
807 struct gred_sched_data *q = table->tab[i];
808 struct tc_gred_qopt opt;
809 unsigned long qavg;
810
811 memset(&opt, 0, sizeof(opt));
812
813 if (!q) {
814 /* hack -- fix at some point with proper message
815 This is how we indicate to tc that there is no VQ
816 at this DP */
817
818 opt.DP = MAX_DPs + i;
819 goto append_opt;
820 }
821
822 opt.limit = q->limit;
823 opt.DP = q->DP;
824 opt.backlog = gred_backlog(table, q, sch);
825 opt.prio = q->prio;
826 opt.qth_min = q->parms.qth_min >> q->parms.Wlog;
827 opt.qth_max = q->parms.qth_max >> q->parms.Wlog;
828 opt.Wlog = q->parms.Wlog;
829 opt.Plog = q->parms.Plog;
830 opt.Scell_log = q->parms.Scell_log;
831 opt.early = q->stats.prob_drop;
832 opt.forced = q->stats.forced_drop;
833 opt.pdrop = q->stats.pdrop;
834 opt.packets = q->packetsin;
835 opt.bytesin = q->bytesin;
836
837 if (gred_wred_mode(table))
838 gred_load_wred_set(table, q);
839
840 qavg = red_calc_qavg(p: &q->parms, v: &q->vars,
841 backlog: q->vars.qavg >> q->parms.Wlog);
842 opt.qave = qavg >> q->parms.Wlog;
843
844append_opt:
845 if (nla_append(skb, attrlen: sizeof(opt), data: &opt) < 0)
846 goto nla_put_failure;
847 }
848
849 nla_nest_end(skb, start: parms);
850
851 /* Dump the VQs again, in more structured way */
852 vqs = nla_nest_start_noflag(skb, attrtype: TCA_GRED_VQ_LIST);
853 if (!vqs)
854 goto nla_put_failure;
855
856 for (i = 0; i < MAX_DPs; i++) {
857 struct gred_sched_data *q = table->tab[i];
858 struct nlattr *vq;
859
860 if (!q)
861 continue;
862
863 vq = nla_nest_start_noflag(skb, attrtype: TCA_GRED_VQ_ENTRY);
864 if (!vq)
865 goto nla_put_failure;
866
867 if (nla_put_u32(skb, attrtype: TCA_GRED_VQ_DP, value: q->DP))
868 goto nla_put_failure;
869
870 if (nla_put_u32(skb, attrtype: TCA_GRED_VQ_FLAGS, value: q->red_flags))
871 goto nla_put_failure;
872
873 /* Stats */
874 if (nla_put_u64_64bit(skb, attrtype: TCA_GRED_VQ_STAT_BYTES, value: q->bytesin,
875 padattr: TCA_GRED_VQ_PAD))
876 goto nla_put_failure;
877 if (nla_put_u32(skb, attrtype: TCA_GRED_VQ_STAT_PACKETS, value: q->packetsin))
878 goto nla_put_failure;
879 if (nla_put_u32(skb, attrtype: TCA_GRED_VQ_STAT_BACKLOG,
880 value: gred_backlog(table, q, sch)))
881 goto nla_put_failure;
882 if (nla_put_u32(skb, attrtype: TCA_GRED_VQ_STAT_PROB_DROP,
883 value: q->stats.prob_drop))
884 goto nla_put_failure;
885 if (nla_put_u32(skb, attrtype: TCA_GRED_VQ_STAT_PROB_MARK,
886 value: q->stats.prob_mark))
887 goto nla_put_failure;
888 if (nla_put_u32(skb, attrtype: TCA_GRED_VQ_STAT_FORCED_DROP,
889 value: q->stats.forced_drop))
890 goto nla_put_failure;
891 if (nla_put_u32(skb, attrtype: TCA_GRED_VQ_STAT_FORCED_MARK,
892 value: q->stats.forced_mark))
893 goto nla_put_failure;
894 if (nla_put_u32(skb, attrtype: TCA_GRED_VQ_STAT_PDROP, value: q->stats.pdrop))
895 goto nla_put_failure;
896
897 nla_nest_end(skb, start: vq);
898 }
899 nla_nest_end(skb, start: vqs);
900
901 return nla_nest_end(skb, start: opts);
902
903nla_put_failure:
904 nla_nest_cancel(skb, start: opts);
905 return -EMSGSIZE;
906}
907
908static void gred_destroy(struct Qdisc *sch)
909{
910 struct gred_sched *table = qdisc_priv(sch);
911 int i;
912
913 for (i = 0; i < table->DPs; i++)
914 gred_destroy_vq(q: table->tab[i]);
915
916 gred_offload(sch, command: TC_GRED_DESTROY);
917 kfree(objp: table->opt);
918}
919
920static struct Qdisc_ops gred_qdisc_ops __read_mostly = {
921 .id = "gred",
922 .priv_size = sizeof(struct gred_sched),
923 .enqueue = gred_enqueue,
924 .dequeue = gred_dequeue,
925 .peek = qdisc_peek_head,
926 .init = gred_init,
927 .reset = gred_reset,
928 .destroy = gred_destroy,
929 .change = gred_change,
930 .dump = gred_dump,
931 .owner = THIS_MODULE,
932};
933
934static int __init gred_module_init(void)
935{
936 return register_qdisc(qops: &gred_qdisc_ops);
937}
938
939static void __exit gred_module_exit(void)
940{
941 unregister_qdisc(qops: &gred_qdisc_ops);
942}
943
944module_init(gred_module_init)
945module_exit(gred_module_exit)
946
947MODULE_LICENSE("GPL");
948

source code of linux/net/sched/sch_gred.c