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