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
30 struct gred_sched_data;
31 struct gred_sched;
32
33 struct 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
47 enum {
48 GRED_WRED_MODE = 1,
49 GRED_RIO_MODE,
50 };
51
52 struct 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
gred_wred_mode(struct gred_sched * table)62 static inline int gred_wred_mode(struct gred_sched *table)
63 {
64 return test_bit(GRED_WRED_MODE, &table->flags);
65 }
66
gred_enable_wred_mode(struct gred_sched * table)67 static inline void gred_enable_wred_mode(struct gred_sched *table)
68 {
69 __set_bit(GRED_WRED_MODE, &table->flags);
70 }
71
gred_disable_wred_mode(struct gred_sched * table)72 static inline void gred_disable_wred_mode(struct gred_sched *table)
73 {
74 __clear_bit(GRED_WRED_MODE, &table->flags);
75 }
76
gred_rio_mode(struct gred_sched * table)77 static inline int gred_rio_mode(struct gred_sched *table)
78 {
79 return test_bit(GRED_RIO_MODE, &table->flags);
80 }
81
gred_enable_rio_mode(struct gred_sched * table)82 static inline void gred_enable_rio_mode(struct gred_sched *table)
83 {
84 __set_bit(GRED_RIO_MODE, &table->flags);
85 }
86
gred_disable_rio_mode(struct gred_sched * table)87 static inline void gred_disable_rio_mode(struct gred_sched *table)
88 {
89 __clear_bit(GRED_RIO_MODE, &table->flags);
90 }
91
gred_wred_mode_check(struct Qdisc * sch)92 static 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
gred_backlog(struct gred_sched * table,struct gred_sched_data * q,struct Qdisc * sch)113 static 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
tc_index_to_dp(struct sk_buff * skb)123 static inline u16 tc_index_to_dp(struct sk_buff *skb)
124 {
125 return skb->tc_index & GRED_VQ_MASK;
126 }
127
gred_load_wred_set(const struct gred_sched * table,struct gred_sched_data * q)128 static 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
gred_store_wred_set(struct gred_sched * table,struct gred_sched_data * q)135 static 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
gred_use_ecn(struct gred_sched_data * q)142 static int gred_use_ecn(struct gred_sched_data *q)
143 {
144 return q->red_flags & TC_RED_ECN;
145 }
146
gred_use_harddrop(struct gred_sched_data * q)147 static int gred_use_harddrop(struct gred_sched_data *q)
148 {
149 return q->red_flags & TC_RED_HARDDROP;
150 }
151
gred_per_vq_red_flags_used(struct gred_sched * table)152 static 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
gred_enqueue(struct sk_buff * skb,struct Qdisc * sch,struct sk_buff ** to_free)165 static 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(t) && gred_rio_mode(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(&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(t))
210 gred_load_wred_set(t, q);
211
212 q->vars.qavg = red_calc_qavg(&q->parms,
213 &q->vars,
214 gred_backlog(t, q, sch));
215
216 if (red_is_idling(&q->vars))
217 red_end_of_idle_period(&q->vars);
218
219 if (gred_wred_mode(t))
220 gred_store_wred_set(t, q);
221
222 switch (red_action(&q->parms, &q->vars, 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(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++;
253 drop:
254 return qdisc_drop(skb, sch, to_free);
255
256 congestion_drop:
257 qdisc_drop(skb, sch, to_free);
258 return NET_XMIT_CN;
259 }
260
gred_dequeue(struct Qdisc * sch)261 static 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(t)) {
279 if (!sch->qstats.backlog)
280 red_start_of_idle_period(&t->wred_set);
281 } else {
282 if (!q->backlog)
283 red_start_of_idle_period(&q->vars);
284 }
285 }
286
287 return skb;
288 }
289
290 return NULL;
291 }
292
gred_reset(struct Qdisc * sch)293 static 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(&q->vars);
307 q->backlog = 0;
308 }
309 }
310
gred_offload(struct Qdisc * sch,enum tc_gred_command command)311 static 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(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
gred_offload_dump_stats(struct Qdisc * sch)354 static 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(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(&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(sch, TC_SETUP_QDISC_GRED, 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 for (i = 0; i < MAX_DPs; i++) {
381 if (!table->tab[i])
382 continue;
383 table->tab[i]->packetsin += u64_stats_read(&hw_stats->stats.bstats[i].packets);
384 table->tab[i]->bytesin += u64_stats_read(&hw_stats->stats.bstats[i].bytes);
385 table->tab[i]->backlog += hw_stats->stats.qstats[i].backlog;
386
387 bytes += u64_stats_read(&hw_stats->stats.bstats[i].bytes);
388 packets += u64_stats_read(&hw_stats->stats.bstats[i].packets);
389 sch->qstats.qlen += hw_stats->stats.qstats[i].qlen;
390 sch->qstats.backlog += hw_stats->stats.qstats[i].backlog;
391 sch->qstats.drops += hw_stats->stats.qstats[i].drops;
392 sch->qstats.requeues += hw_stats->stats.qstats[i].requeues;
393 sch->qstats.overlimits += hw_stats->stats.qstats[i].overlimits;
394 }
395 _bstats_update(&sch->bstats, bytes, packets);
396
397 kfree(hw_stats);
398 return ret;
399 }
400
gred_destroy_vq(struct gred_sched_data * q)401 static inline void gred_destroy_vq(struct gred_sched_data *q)
402 {
403 kfree(q);
404 }
405
gred_change_table_def(struct Qdisc * sch,struct nlattr * dps,struct netlink_ext_ack * extack)406 static int gred_change_table_def(struct Qdisc *sch, struct nlattr *dps,
407 struct netlink_ext_ack *extack)
408 {
409 struct gred_sched *table = qdisc_priv(sch);
410 struct tc_gred_sopt *sopt;
411 bool red_flags_changed;
412 int i;
413
414 if (!dps)
415 return -EINVAL;
416
417 sopt = nla_data(dps);
418
419 if (sopt->DPs > MAX_DPs) {
420 NL_SET_ERR_MSG_MOD(extack, "number of virtual queues too high");
421 return -EINVAL;
422 }
423 if (sopt->DPs == 0) {
424 NL_SET_ERR_MSG_MOD(extack,
425 "number of virtual queues can't be 0");
426 return -EINVAL;
427 }
428 if (sopt->def_DP >= sopt->DPs) {
429 NL_SET_ERR_MSG_MOD(extack, "default virtual queue above virtual queue count");
430 return -EINVAL;
431 }
432 if (sopt->flags && gred_per_vq_red_flags_used(table)) {
433 NL_SET_ERR_MSG_MOD(extack, "can't set per-Qdisc RED flags when per-virtual queue flags are used");
434 return -EINVAL;
435 }
436
437 sch_tree_lock(sch);
438 table->DPs = sopt->DPs;
439 table->def = sopt->def_DP;
440 red_flags_changed = table->red_flags != sopt->flags;
441 table->red_flags = sopt->flags;
442
443 /*
444 * Every entry point to GRED is synchronized with the above code
445 * and the DP is checked against DPs, i.e. shadowed VQs can no
446 * longer be found so we can unlock right here.
447 */
448 sch_tree_unlock(sch);
449
450 if (sopt->grio) {
451 gred_enable_rio_mode(table);
452 gred_disable_wred_mode(table);
453 if (gred_wred_mode_check(sch))
454 gred_enable_wred_mode(table);
455 } else {
456 gred_disable_rio_mode(table);
457 gred_disable_wred_mode(table);
458 }
459
460 if (red_flags_changed)
461 for (i = 0; i < table->DPs; i++)
462 if (table->tab[i])
463 table->tab[i]->red_flags =
464 table->red_flags & GRED_VQ_RED_FLAGS;
465
466 for (i = table->DPs; i < MAX_DPs; i++) {
467 if (table->tab[i]) {
468 pr_warn("GRED: Warning: Destroying shadowed VQ 0x%x\n",
469 i);
470 gred_destroy_vq(table->tab[i]);
471 table->tab[i] = NULL;
472 }
473 }
474
475 gred_offload(sch, TC_GRED_REPLACE);
476 return 0;
477 }
478
gred_change_vq(struct Qdisc * sch,int dp,struct tc_gred_qopt * ctl,int prio,u8 * stab,u32 max_P,struct gred_sched_data ** prealloc,struct netlink_ext_ack * extack)479 static inline int gred_change_vq(struct Qdisc *sch, int dp,
480 struct tc_gred_qopt *ctl, int prio,
481 u8 *stab, u32 max_P,
482 struct gred_sched_data **prealloc,
483 struct netlink_ext_ack *extack)
484 {
485 struct gred_sched *table = qdisc_priv(sch);
486 struct gred_sched_data *q = table->tab[dp];
487
488 if (!red_check_params(ctl->qth_min, ctl->qth_max, ctl->Wlog, ctl->Scell_log, stab)) {
489 NL_SET_ERR_MSG_MOD(extack, "invalid RED parameters");
490 return -EINVAL;
491 }
492
493 if (!q) {
494 table->tab[dp] = q = *prealloc;
495 *prealloc = NULL;
496 if (!q)
497 return -ENOMEM;
498 q->red_flags = table->red_flags & GRED_VQ_RED_FLAGS;
499 }
500
501 q->DP = dp;
502 q->prio = prio;
503 if (ctl->limit > sch->limit)
504 q->limit = sch->limit;
505 else
506 q->limit = ctl->limit;
507
508 if (q->backlog == 0)
509 red_end_of_idle_period(&q->vars);
510
511 red_set_parms(&q->parms,
512 ctl->qth_min, ctl->qth_max, ctl->Wlog, ctl->Plog,
513 ctl->Scell_log, stab, max_P);
514 red_set_vars(&q->vars);
515 return 0;
516 }
517
518 static const struct nla_policy gred_vq_policy[TCA_GRED_VQ_MAX + 1] = {
519 [TCA_GRED_VQ_DP] = { .type = NLA_U32 },
520 [TCA_GRED_VQ_FLAGS] = { .type = NLA_U32 },
521 };
522
523 static const struct nla_policy gred_vqe_policy[TCA_GRED_VQ_ENTRY_MAX + 1] = {
524 [TCA_GRED_VQ_ENTRY] = { .type = NLA_NESTED },
525 };
526
527 static const struct nla_policy gred_policy[TCA_GRED_MAX + 1] = {
528 [TCA_GRED_PARMS] = { .len = sizeof(struct tc_gred_qopt) },
529 [TCA_GRED_STAB] = { .len = 256 },
530 [TCA_GRED_DPS] = { .len = sizeof(struct tc_gred_sopt) },
531 [TCA_GRED_MAX_P] = { .type = NLA_U32 },
532 [TCA_GRED_LIMIT] = { .type = NLA_U32 },
533 [TCA_GRED_VQ_LIST] = { .type = NLA_NESTED },
534 };
535
gred_vq_apply(struct gred_sched * table,const struct nlattr * entry)536 static void gred_vq_apply(struct gred_sched *table, const struct nlattr *entry)
537 {
538 struct nlattr *tb[TCA_GRED_VQ_MAX + 1];
539 u32 dp;
540
541 nla_parse_nested_deprecated(tb, TCA_GRED_VQ_MAX, entry,
542 gred_vq_policy, NULL);
543
544 dp = nla_get_u32(tb[TCA_GRED_VQ_DP]);
545
546 if (tb[TCA_GRED_VQ_FLAGS])
547 table->tab[dp]->red_flags = nla_get_u32(tb[TCA_GRED_VQ_FLAGS]);
548 }
549
gred_vqs_apply(struct gred_sched * table,struct nlattr * vqs)550 static void gred_vqs_apply(struct gred_sched *table, struct nlattr *vqs)
551 {
552 const struct nlattr *attr;
553 int rem;
554
555 nla_for_each_nested(attr, vqs, rem) {
556 switch (nla_type(attr)) {
557 case TCA_GRED_VQ_ENTRY:
558 gred_vq_apply(table, attr);
559 break;
560 }
561 }
562 }
563
gred_vq_validate(struct gred_sched * table,u32 cdp,const struct nlattr * entry,struct netlink_ext_ack * extack)564 static int gred_vq_validate(struct gred_sched *table, u32 cdp,
565 const struct nlattr *entry,
566 struct netlink_ext_ack *extack)
567 {
568 struct nlattr *tb[TCA_GRED_VQ_MAX + 1];
569 int err;
570 u32 dp;
571
572 err = nla_parse_nested_deprecated(tb, TCA_GRED_VQ_MAX, entry,
573 gred_vq_policy, extack);
574 if (err < 0)
575 return err;
576
577 if (!tb[TCA_GRED_VQ_DP]) {
578 NL_SET_ERR_MSG_MOD(extack, "Virtual queue with no index specified");
579 return -EINVAL;
580 }
581 dp = nla_get_u32(tb[TCA_GRED_VQ_DP]);
582 if (dp >= table->DPs) {
583 NL_SET_ERR_MSG_MOD(extack, "Virtual queue with index out of bounds");
584 return -EINVAL;
585 }
586 if (dp != cdp && !table->tab[dp]) {
587 NL_SET_ERR_MSG_MOD(extack, "Virtual queue not yet instantiated");
588 return -EINVAL;
589 }
590
591 if (tb[TCA_GRED_VQ_FLAGS]) {
592 u32 red_flags = nla_get_u32(tb[TCA_GRED_VQ_FLAGS]);
593
594 if (table->red_flags && table->red_flags != red_flags) {
595 NL_SET_ERR_MSG_MOD(extack, "can't change per-virtual queue RED flags when per-Qdisc flags are used");
596 return -EINVAL;
597 }
598 if (red_flags & ~GRED_VQ_RED_FLAGS) {
599 NL_SET_ERR_MSG_MOD(extack,
600 "invalid RED flags specified");
601 return -EINVAL;
602 }
603 }
604
605 return 0;
606 }
607
gred_vqs_validate(struct gred_sched * table,u32 cdp,struct nlattr * vqs,struct netlink_ext_ack * extack)608 static int gred_vqs_validate(struct gred_sched *table, u32 cdp,
609 struct nlattr *vqs, struct netlink_ext_ack *extack)
610 {
611 const struct nlattr *attr;
612 int rem, err;
613
614 err = nla_validate_nested_deprecated(vqs, TCA_GRED_VQ_ENTRY_MAX,
615 gred_vqe_policy, extack);
616 if (err < 0)
617 return err;
618
619 nla_for_each_nested(attr, vqs, rem) {
620 switch (nla_type(attr)) {
621 case TCA_GRED_VQ_ENTRY:
622 err = gred_vq_validate(table, cdp, attr, extack);
623 if (err)
624 return err;
625 break;
626 default:
627 NL_SET_ERR_MSG_MOD(extack, "GRED_VQ_LIST can contain only entry attributes");
628 return -EINVAL;
629 }
630 }
631
632 if (rem > 0) {
633 NL_SET_ERR_MSG_MOD(extack, "Trailing data after parsing virtual queue list");
634 return -EINVAL;
635 }
636
637 return 0;
638 }
639
gred_change(struct Qdisc * sch,struct nlattr * opt,struct netlink_ext_ack * extack)640 static int gred_change(struct Qdisc *sch, struct nlattr *opt,
641 struct netlink_ext_ack *extack)
642 {
643 struct gred_sched *table = qdisc_priv(sch);
644 struct tc_gred_qopt *ctl;
645 struct nlattr *tb[TCA_GRED_MAX + 1];
646 int err, prio = GRED_DEF_PRIO;
647 u8 *stab;
648 u32 max_P;
649 struct gred_sched_data *prealloc;
650
651 if (opt == NULL)
652 return -EINVAL;
653
654 err = nla_parse_nested_deprecated(tb, TCA_GRED_MAX, opt, gred_policy,
655 extack);
656 if (err < 0)
657 return err;
658
659 if (tb[TCA_GRED_PARMS] == NULL && tb[TCA_GRED_STAB] == NULL) {
660 if (tb[TCA_GRED_LIMIT] != NULL)
661 sch->limit = nla_get_u32(tb[TCA_GRED_LIMIT]);
662 return gred_change_table_def(sch, tb[TCA_GRED_DPS], extack);
663 }
664
665 if (tb[TCA_GRED_PARMS] == NULL ||
666 tb[TCA_GRED_STAB] == NULL ||
667 tb[TCA_GRED_LIMIT] != NULL) {
668 NL_SET_ERR_MSG_MOD(extack, "can't configure Qdisc and virtual queue at the same time");
669 return -EINVAL;
670 }
671
672 max_P = tb[TCA_GRED_MAX_P] ? nla_get_u32(tb[TCA_GRED_MAX_P]) : 0;
673
674 ctl = nla_data(tb[TCA_GRED_PARMS]);
675 stab = nla_data(tb[TCA_GRED_STAB]);
676
677 if (ctl->DP >= table->DPs) {
678 NL_SET_ERR_MSG_MOD(extack, "virtual queue index above virtual queue count");
679 return -EINVAL;
680 }
681
682 if (tb[TCA_GRED_VQ_LIST]) {
683 err = gred_vqs_validate(table, ctl->DP, tb[TCA_GRED_VQ_LIST],
684 extack);
685 if (err)
686 return err;
687 }
688
689 if (gred_rio_mode(table)) {
690 if (ctl->prio == 0) {
691 int def_prio = GRED_DEF_PRIO;
692
693 if (table->tab[table->def])
694 def_prio = table->tab[table->def]->prio;
695
696 printk(KERN_DEBUG "GRED: DP %u does not have a prio "
697 "setting default to %d\n", ctl->DP, def_prio);
698
699 prio = def_prio;
700 } else
701 prio = ctl->prio;
702 }
703
704 prealloc = kzalloc(sizeof(*prealloc), GFP_KERNEL);
705 sch_tree_lock(sch);
706
707 err = gred_change_vq(sch, ctl->DP, ctl, prio, stab, max_P, &prealloc,
708 extack);
709 if (err < 0)
710 goto err_unlock_free;
711
712 if (tb[TCA_GRED_VQ_LIST])
713 gred_vqs_apply(table, tb[TCA_GRED_VQ_LIST]);
714
715 if (gred_rio_mode(table)) {
716 gred_disable_wred_mode(table);
717 if (gred_wred_mode_check(sch))
718 gred_enable_wred_mode(table);
719 }
720
721 sch_tree_unlock(sch);
722 kfree(prealloc);
723
724 gred_offload(sch, TC_GRED_REPLACE);
725 return 0;
726
727 err_unlock_free:
728 sch_tree_unlock(sch);
729 kfree(prealloc);
730 return err;
731 }
732
gred_init(struct Qdisc * sch,struct nlattr * opt,struct netlink_ext_ack * extack)733 static int gred_init(struct Qdisc *sch, struct nlattr *opt,
734 struct netlink_ext_ack *extack)
735 {
736 struct gred_sched *table = qdisc_priv(sch);
737 struct nlattr *tb[TCA_GRED_MAX + 1];
738 int err;
739
740 if (!opt)
741 return -EINVAL;
742
743 err = nla_parse_nested_deprecated(tb, TCA_GRED_MAX, opt, gred_policy,
744 extack);
745 if (err < 0)
746 return err;
747
748 if (tb[TCA_GRED_PARMS] || tb[TCA_GRED_STAB]) {
749 NL_SET_ERR_MSG_MOD(extack,
750 "virtual queue configuration can't be specified at initialization time");
751 return -EINVAL;
752 }
753
754 if (tb[TCA_GRED_LIMIT])
755 sch->limit = nla_get_u32(tb[TCA_GRED_LIMIT]);
756 else
757 sch->limit = qdisc_dev(sch)->tx_queue_len
758 * psched_mtu(qdisc_dev(sch));
759
760 if (qdisc_dev(sch)->netdev_ops->ndo_setup_tc) {
761 table->opt = kzalloc(sizeof(*table->opt), GFP_KERNEL);
762 if (!table->opt)
763 return -ENOMEM;
764 }
765
766 return gred_change_table_def(sch, tb[TCA_GRED_DPS], extack);
767 }
768
gred_dump(struct Qdisc * sch,struct sk_buff * skb)769 static int gred_dump(struct Qdisc *sch, struct sk_buff *skb)
770 {
771 struct gred_sched *table = qdisc_priv(sch);
772 struct nlattr *parms, *vqs, *opts = NULL;
773 int i;
774 u32 max_p[MAX_DPs];
775 struct tc_gred_sopt sopt = {
776 .DPs = table->DPs,
777 .def_DP = table->def,
778 .grio = gred_rio_mode(table),
779 .flags = table->red_flags,
780 };
781
782 if (gred_offload_dump_stats(sch))
783 goto nla_put_failure;
784
785 opts = nla_nest_start_noflag(skb, TCA_OPTIONS);
786 if (opts == NULL)
787 goto nla_put_failure;
788 if (nla_put(skb, TCA_GRED_DPS, sizeof(sopt), &sopt))
789 goto nla_put_failure;
790
791 for (i = 0; i < MAX_DPs; i++) {
792 struct gred_sched_data *q = table->tab[i];
793
794 max_p[i] = q ? q->parms.max_P : 0;
795 }
796 if (nla_put(skb, TCA_GRED_MAX_P, sizeof(max_p), max_p))
797 goto nla_put_failure;
798
799 if (nla_put_u32(skb, TCA_GRED_LIMIT, sch->limit))
800 goto nla_put_failure;
801
802 /* Old style all-in-one dump of VQs */
803 parms = nla_nest_start_noflag(skb, TCA_GRED_PARMS);
804 if (parms == NULL)
805 goto nla_put_failure;
806
807 for (i = 0; i < MAX_DPs; i++) {
808 struct gred_sched_data *q = table->tab[i];
809 struct tc_gred_qopt opt;
810 unsigned long qavg;
811
812 memset(&opt, 0, sizeof(opt));
813
814 if (!q) {
815 /* hack -- fix at some point with proper message
816 This is how we indicate to tc that there is no VQ
817 at this DP */
818
819 opt.DP = MAX_DPs + i;
820 goto append_opt;
821 }
822
823 opt.limit = q->limit;
824 opt.DP = q->DP;
825 opt.backlog = gred_backlog(table, q, sch);
826 opt.prio = q->prio;
827 opt.qth_min = q->parms.qth_min >> q->parms.Wlog;
828 opt.qth_max = q->parms.qth_max >> q->parms.Wlog;
829 opt.Wlog = q->parms.Wlog;
830 opt.Plog = q->parms.Plog;
831 opt.Scell_log = q->parms.Scell_log;
832 opt.other = q->stats.other;
833 opt.early = q->stats.prob_drop;
834 opt.forced = q->stats.forced_drop;
835 opt.pdrop = q->stats.pdrop;
836 opt.packets = q->packetsin;
837 opt.bytesin = q->bytesin;
838
839 if (gred_wred_mode(table))
840 gred_load_wred_set(table, q);
841
842 qavg = red_calc_qavg(&q->parms, &q->vars,
843 q->vars.qavg >> q->parms.Wlog);
844 opt.qave = qavg >> q->parms.Wlog;
845
846 append_opt:
847 if (nla_append(skb, sizeof(opt), &opt) < 0)
848 goto nla_put_failure;
849 }
850
851 nla_nest_end(skb, parms);
852
853 /* Dump the VQs again, in more structured way */
854 vqs = nla_nest_start_noflag(skb, TCA_GRED_VQ_LIST);
855 if (!vqs)
856 goto nla_put_failure;
857
858 for (i = 0; i < MAX_DPs; i++) {
859 struct gred_sched_data *q = table->tab[i];
860 struct nlattr *vq;
861
862 if (!q)
863 continue;
864
865 vq = nla_nest_start_noflag(skb, TCA_GRED_VQ_ENTRY);
866 if (!vq)
867 goto nla_put_failure;
868
869 if (nla_put_u32(skb, TCA_GRED_VQ_DP, q->DP))
870 goto nla_put_failure;
871
872 if (nla_put_u32(skb, TCA_GRED_VQ_FLAGS, q->red_flags))
873 goto nla_put_failure;
874
875 /* Stats */
876 if (nla_put_u64_64bit(skb, TCA_GRED_VQ_STAT_BYTES, q->bytesin,
877 TCA_GRED_VQ_PAD))
878 goto nla_put_failure;
879 if (nla_put_u32(skb, TCA_GRED_VQ_STAT_PACKETS, q->packetsin))
880 goto nla_put_failure;
881 if (nla_put_u32(skb, TCA_GRED_VQ_STAT_BACKLOG,
882 gred_backlog(table, q, sch)))
883 goto nla_put_failure;
884 if (nla_put_u32(skb, TCA_GRED_VQ_STAT_PROB_DROP,
885 q->stats.prob_drop))
886 goto nla_put_failure;
887 if (nla_put_u32(skb, TCA_GRED_VQ_STAT_PROB_MARK,
888 q->stats.prob_mark))
889 goto nla_put_failure;
890 if (nla_put_u32(skb, TCA_GRED_VQ_STAT_FORCED_DROP,
891 q->stats.forced_drop))
892 goto nla_put_failure;
893 if (nla_put_u32(skb, TCA_GRED_VQ_STAT_FORCED_MARK,
894 q->stats.forced_mark))
895 goto nla_put_failure;
896 if (nla_put_u32(skb, TCA_GRED_VQ_STAT_PDROP, q->stats.pdrop))
897 goto nla_put_failure;
898 if (nla_put_u32(skb, TCA_GRED_VQ_STAT_OTHER, q->stats.other))
899 goto nla_put_failure;
900
901 nla_nest_end(skb, vq);
902 }
903 nla_nest_end(skb, vqs);
904
905 return nla_nest_end(skb, opts);
906
907 nla_put_failure:
908 nla_nest_cancel(skb, opts);
909 return -EMSGSIZE;
910 }
911
gred_destroy(struct Qdisc * sch)912 static void gred_destroy(struct Qdisc *sch)
913 {
914 struct gred_sched *table = qdisc_priv(sch);
915 int i;
916
917 for (i = 0; i < table->DPs; i++) {
918 if (table->tab[i])
919 gred_destroy_vq(table->tab[i]);
920 }
921 gred_offload(sch, TC_GRED_DESTROY);
922 kfree(table->opt);
923 }
924
925 static struct Qdisc_ops gred_qdisc_ops __read_mostly = {
926 .id = "gred",
927 .priv_size = sizeof(struct gred_sched),
928 .enqueue = gred_enqueue,
929 .dequeue = gred_dequeue,
930 .peek = qdisc_peek_head,
931 .init = gred_init,
932 .reset = gred_reset,
933 .destroy = gred_destroy,
934 .change = gred_change,
935 .dump = gred_dump,
936 .owner = THIS_MODULE,
937 };
938
gred_module_init(void)939 static int __init gred_module_init(void)
940 {
941 return register_qdisc(&gred_qdisc_ops);
942 }
943
gred_module_exit(void)944 static void __exit gred_module_exit(void)
945 {
946 unregister_qdisc(&gred_qdisc_ops);
947 }
948
949 module_init(gred_module_init)
950 module_exit(gred_module_exit)
951
952 MODULE_LICENSE("GPL");
953