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(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++; 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(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 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(&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(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(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 sch_tree_lock(sch); 381 for (i = 0; i < MAX_DPs; i++) { 382 if (!table->tab[i]) 383 continue; 384 table->tab[i]->packetsin += u64_stats_read(&hw_stats->stats.bstats[i].packets); 385 table->tab[i]->bytesin += u64_stats_read(&hw_stats->stats.bstats[i].bytes); 386 table->tab[i]->backlog += hw_stats->stats.qstats[i].backlog; 387 388 bytes += u64_stats_read(&hw_stats->stats.bstats[i].bytes); 389 packets += u64_stats_read(&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(&sch->bstats, bytes, packets); 397 sch_tree_unlock(sch); 398 399 kfree(hw_stats); 400 return ret; 401} 402 403static inline void gred_destroy_vq(struct gred_sched_data *q) 404{ 405 kfree(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(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(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(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(table->tab[i]); 473 table->tab[i] = NULL; 474 } 475 } 476 477 gred_offload(sch, 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(ctl->qth_min, ctl->qth_max, ctl->Wlog, 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(&q->vars); 512 513 red_set_parms(&q->parms, 514 ctl->qth_min, ctl->qth_max, ctl->Wlog, ctl->Plog, 515 ctl->Scell_log, stab, max_P); 516 red_set_vars(&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, entry, 544 gred_vq_policy, NULL); 545 546 dp = nla_get_u32(tb[TCA_GRED_VQ_DP]); 547 548 if (tb[TCA_GRED_VQ_FLAGS]) 549 table->tab[dp]->red_flags = nla_get_u32(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(attr)) { 559 case TCA_GRED_VQ_ENTRY: 560 gred_vq_apply(table, 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, entry, 575 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(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(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(vqs, TCA_GRED_VQ_ENTRY_MAX, 617 gred_vqe_policy, extack); 618 if (err < 0) 619 return err; 620 621 nla_for_each_nested(attr, vqs, rem) { 622 switch (nla_type(attr)) { 623 case TCA_GRED_VQ_ENTRY: 624 err = gred_vq_validate(table, cdp, 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, opt, 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(tb[TCA_GRED_LIMIT]); 661 return gred_change_table_def(sch, 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(tb[TCA_GRED_MAX_P]) : 0; 672 673 ctl = nla_data(tb[TCA_GRED_PARMS]); 674 stab = nla_data(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, ctl->DP, 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(sizeof(*prealloc), GFP_KERNEL); 704 sch_tree_lock(sch); 705 706 err = gred_change_vq(sch, ctl->DP, ctl, prio, stab, max_P, &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, 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(sch); 721 kfree(prealloc); 722 723 gred_offload(sch, TC_GRED_REPLACE); 724 return 0; 725 726err_unlock_free: 727 sch_tree_unlock(sch); 728 kfree(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, opt, 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(tb[TCA_GRED_LIMIT]); 755 else 756 sch->limit = qdisc_dev(sch)->tx_queue_len 757 * psched_mtu(qdisc_dev(sch)); 758 759 if (qdisc_dev(sch)->netdev_ops->ndo_setup_tc) { 760 table->opt = kzalloc(sizeof(*table->opt), GFP_KERNEL); 761 if (!table->opt) 762 return -ENOMEM; 763 } 764 765 return gred_change_table_def(sch, 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, TCA_OPTIONS); 785 if (opts == NULL) 786 goto nla_put_failure; 787 if (nla_put(skb, TCA_GRED_DPS, sizeof(sopt), &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, TCA_GRED_MAX_P, sizeof(max_p), max_p)) 796 goto nla_put_failure; 797 798 if (nla_put_u32(skb, TCA_GRED_LIMIT, sch->limit)) 799 goto nla_put_failure; 800 801 /* Old style all-in-one dump of VQs */ 802 parms = nla_nest_start_noflag(skb, 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(&q->parms, &q->vars, 841 q->vars.qavg >> q->parms.Wlog); 842 opt.qave = qavg >> q->parms.Wlog; 843 844append_opt: 845 if (nla_append(skb, sizeof(opt), &opt) < 0) 846 goto nla_put_failure; 847 } 848 849 nla_nest_end(skb, parms); 850 851 /* Dump the VQs again, in more structured way */ 852 vqs = nla_nest_start_noflag(skb, 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, TCA_GRED_VQ_ENTRY); 864 if (!vq) 865 goto nla_put_failure; 866 867 if (nla_put_u32(skb, TCA_GRED_VQ_DP, q->DP)) 868 goto nla_put_failure; 869 870 if (nla_put_u32(skb, TCA_GRED_VQ_FLAGS, q->red_flags)) 871 goto nla_put_failure; 872 873 /* Stats */ 874 if (nla_put_u64_64bit(skb, TCA_GRED_VQ_STAT_BYTES, q->bytesin, 875 TCA_GRED_VQ_PAD)) 876 goto nla_put_failure; 877 if (nla_put_u32(skb, TCA_GRED_VQ_STAT_PACKETS, q->packetsin)) 878 goto nla_put_failure; 879 if (nla_put_u32(skb, TCA_GRED_VQ_STAT_BACKLOG, 880 gred_backlog(table, q, sch))) 881 goto nla_put_failure; 882 if (nla_put_u32(skb, TCA_GRED_VQ_STAT_PROB_DROP, 883 q->stats.prob_drop)) 884 goto nla_put_failure; 885 if (nla_put_u32(skb, TCA_GRED_VQ_STAT_PROB_MARK, 886 q->stats.prob_mark)) 887 goto nla_put_failure; 888 if (nla_put_u32(skb, TCA_GRED_VQ_STAT_FORCED_DROP, 889 q->stats.forced_drop)) 890 goto nla_put_failure; 891 if (nla_put_u32(skb, TCA_GRED_VQ_STAT_FORCED_MARK, 892 q->stats.forced_mark)) 893 goto nla_put_failure; 894 if (nla_put_u32(skb, TCA_GRED_VQ_STAT_PDROP, q->stats.pdrop)) 895 goto nla_put_failure; 896 897 nla_nest_end(skb, vq); 898 } 899 nla_nest_end(skb, vqs); 900 901 return nla_nest_end(skb, opts); 902 903nla_put_failure: 904 nla_nest_cancel(skb, 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(table->tab[i]); 915 916 gred_offload(sch, TC_GRED_DESTROY); 917 kfree(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}; 933MODULE_ALIAS_NET_SCH("gred"); 934 935static int __init gred_module_init(void) 936{ 937 return register_qdisc(&gred_qdisc_ops); 938} 939 940static void __exit gred_module_exit(void) 941{ 942 unregister_qdisc(&gred_qdisc_ops); 943} 944 945module_init(gred_module_init) 946module_exit(gred_module_exit) 947 948MODULE_LICENSE("GPL"); 949MODULE_DESCRIPTION("Generic Random Early Detection qdisc"); 950