net/sched/sch_cbq.c

   1 /*
   2  * net/sched/sch_cbq.c  Class-Based Queueing discipline.
   3  *
   4  *              This program is free software; you can redistribute it and/or
   5  *              modify it under the terms of the GNU General Public License
   6  *              as published by the Free Software Foundation; either version
   7  *              2 of the License, or (at your option) any later version.
   8  *
   9  * Authors:     Alexey Kuznetsov, <kuznet@ms2.inr.ac.ru>
  10  *
  11  */
  12
  13 #include <linux/module.h>
  14 #include <linux/slab.h>
  15 #include <linux/types.h>
  16 #include <linux/kernel.h>
  17 #include <linux/string.h>
  18 #include <linux/errno.h>
  19 #include <linux/skbuff.h>
  20 #include <net/netlink.h>
  21 #include <net/pkt_sched.h>
  22
  23
  24 /*      Class-Based Queueing (CBQ) algorithm.
  25         =======================================
  26
  27         Sources: [1] Sally Floyd and Van Jacobson, "Link-sharing and Resource
  28                  Management Models for Packet Networks",
  29                  IEEE/ACM Transactions on Networking, Vol.3, No.4, 1995
  30
  31                  [2] Sally Floyd, "Notes on CBQ and Guaranteed Service", 1995
  32
  33                  [3] Sally Floyd, "Notes on Class-Based Queueing: Setting
  34                  Parameters", 1996
  35
  36                  [4] Sally Floyd and Michael Speer, "Experimental Results
  37                  for Class-Based Queueing", 1998, not published.
  38
  39         -----------------------------------------------------------------------
  40
  41         Algorithm skeleton was taken from NS simulator cbq.cc.
  42         If someone wants to check this code against the LBL version,
  43         he should take into account that ONLY the skeleton was borrowed,
  44         the implementation is different. Particularly:
  45
  46         --- The WRR algorithm is different. Our version looks more
  47         reasonable (I hope) and works when quanta are allowed to be
  48         less than MTU, which is always the case when real time classes
  49         have small rates. Note, that the statement of [3] is
  50         incomplete, delay may actually be estimated even if class
  51         per-round allotment is less than MTU. Namely, if per-round
  52         allotment is W*r_i, and r_1+...+r_k = r < 1
  53
  54         delay_i <= ([MTU/(W*r_i)]*W*r + W*r + k*MTU)/B
  55
  56         In the worst case we have IntServ estimate with D = W*r+k*MTU
  57         and C = MTU*r. The proof (if correct at all) is trivial.
  58
  59
  60         --- It seems that cbq-2.0 is not very accurate. At least, I cannot
  61         interpret some places, which look like wrong translations
  62         from NS. Anyone is advised to find these differences
  63         and explain to me, why I am wrong 8).
  64
  65         --- Linux has no EOI event, so that we cannot estimate true class
  66         idle time. Workaround is to consider the next dequeue event
  67         as sign that previous packet is finished. This is wrong because of
  68         internal device queueing, but on a permanently loaded link it is true.
  69         Moreover, combined with clock integrator, this scheme looks
  70         very close to an ideal solution.  */
  71
  72 struct cbq_sched_data;
  73
  74
  75 struct cbq_class {
  76         struct Qdisc_class_common common;
  77         struct cbq_class        *next_alive;    /* next class with backlog in this priority band */
  78
  79 /* Parameters */
  80         unsigned char           priority;       /* class priority */
  81         unsigned char           priority2;      /* priority to be used after overlimit */
  82         unsigned char           ewma_log;       /* time constant for idle time calculation */
  83         unsigned char           ovl_strategy;
  84 #ifdef CONFIG_NET_CLS_ACT
  85         unsigned char           police;
  86 #endif
  87
  88         u32                     defmap;
  89
  90         /* Link-sharing scheduler parameters */
  91         long                    maxidle;        /* Class parameters: see below. */
  92         long                    offtime;
  93         long                    minidle;
  94         u32                     avpkt;
  95         struct qdisc_rate_table *R_tab;
  96
  97         /* Overlimit strategy parameters */
  98         void                    (*overlimit)(struct cbq_class *cl);
  99         psched_tdiff_t          penalty;
 100
 101         /* General scheduler (WRR) parameters */
 102         long                    allot;
 103         long                    quantum;        /* Allotment per WRR round */
 104         long                    weight;         /* Relative allotment: see below */
 105
 106         struct Qdisc            *qdisc;         /* Ptr to CBQ discipline */
 107         struct cbq_class        *split;         /* Ptr to split node */
 108         struct cbq_class        *share;         /* Ptr to LS parent in the class tree */
 109         struct cbq_class        *tparent;       /* Ptr to tree parent in the class tree */
 110         struct cbq_class        *borrow;        /* NULL if class is bandwidth limited;
 111                                                    parent otherwise */
 112         struct cbq_class        *sibling;       /* Sibling chain */
 113         struct cbq_class        *children;      /* Pointer to children chain */
 114
 115         struct Qdisc            *q;             /* Elementary queueing discipline */
 116
 117
 118 /* Variables */
 119         unsigned char           cpriority;      /* Effective priority */
 120         unsigned char           delayed;
 121         unsigned char           level;          /* level of the class in hierarchy:
 122                                                    0 for leaf classes, and maximal
 123                                                    level of children + 1 for nodes.
 124                                                  */
 125
 126         psched_time_t           last;           /* Last end of service */
 127         psched_time_t           undertime;
 128         long                    avgidle;
 129         long                    deficit;        /* Saved deficit for WRR */
 130         psched_time_t           penalized;
 131         struct gnet_stats_basic_packed bstats;
 132         struct gnet_stats_queue qstats;
 133         struct gnet_stats_rate_est64 rate_est;
 134         struct tc_cbq_xstats    xstats;
 135
 136         struct tcf_proto        *filter_list;
 137
 138         int                     refcnt;
 139         int                     filters;
 140
 141         struct cbq_class        *defaults[TC_PRIO_MAX + 1];
 142 };
 143
 144 struct cbq_sched_data {
 145         struct Qdisc_class_hash clhash;                 /* Hash table of all classes */
 146         int                     nclasses[TC_CBQ_MAXPRIO + 1];
 147         unsigned int            quanta[TC_CBQ_MAXPRIO + 1];
 148
 149         struct cbq_class        link;
 150
 151         unsigned int            activemask;
 152         struct cbq_class        *active[TC_CBQ_MAXPRIO + 1];    /* List of all classes
 153                                                                    with backlog */
 154
 155 #ifdef CONFIG_NET_CLS_ACT
 156         struct cbq_class        *rx_class;
 157 #endif
 158         struct cbq_class        *tx_class;
 159         struct cbq_class        *tx_borrowed;
 160         int                     tx_len;
 161         psched_time_t           now;            /* Cached timestamp */
 162         psched_time_t           now_rt;         /* Cached real time */
 163         unsigned int            pmask;
 164
 165         struct hrtimer          delay_timer;
 166         struct qdisc_watchdog   watchdog;       /* Watchdog timer,
 167                                                    started when CBQ has
 168                                                    backlog, but cannot
 169                                                    transmit just now */
 170         psched_tdiff_t          wd_expires;
 171         int                     toplevel;
 172         u32                     hgenerator;
 173 };
 174
 175
 176 #define L2T(cl, len)    qdisc_l2t((cl)->R_tab, len)
 177
 178 static inline struct cbq_class *
 179 cbq_class_lookup(struct cbq_sched_data *q, u32 classid)
 180 {
 181         struct Qdisc_class_common *clc;
 182
 183         clc = qdisc_class_find(&q->clhash, classid);
 184         if (clc == NULL)
 185                 return NULL;
 186         return container_of(clc, struct cbq_class, common);
 187 }
 188
 189 #ifdef CONFIG_NET_CLS_ACT
 190
 191 static struct cbq_class *
 192 cbq_reclassify(struct sk_buff *skb, struct cbq_class *this)
 193 {
 194         struct cbq_class *cl;
 195
 196         for (cl = this->tparent; cl; cl = cl->tparent) {
 197                 struct cbq_class *new = cl->defaults[TC_PRIO_BESTEFFORT];
 198
 199                 if (new != NULL && new != this)
 200                         return new;
 201         }
 202         return NULL;
 203 }
 204
 205 #endif
 206
 207 /* Classify packet. The procedure is pretty complicated, but
 208  * it allows us to combine link sharing and priority scheduling
 209  * transparently.
 210  *
 211  * Namely, you can put link sharing rules (f.e. route based) at root of CBQ,
 212  * so that it resolves to split nodes. Then packets are classified
 213  * by logical priority, or a more specific classifier may be attached
 214  * to the split node.
 215  */
 216
 217 static struct cbq_class *
 218 cbq_classify(struct sk_buff *skb, struct Qdisc *sch, int *qerr)
 219 {
 220         struct cbq_sched_data *q = qdisc_priv(sch);
 221         struct cbq_class *head = &q->link;
 222         struct cbq_class **defmap;
 223         struct cbq_class *cl = NULL;
 224         u32 prio = skb->priority;
 225         struct tcf_result res;
 226
 227         /*
 228          *  Step 1. If skb->priority points to one of our classes, use it.
 229          */
 230         if (TC_H_MAJ(prio ^ sch->handle) == 0 &&
 231             (cl = cbq_class_lookup(q, prio)) != NULL)
 232                 return cl;
 233
 234         *qerr = NET_XMIT_SUCCESS | __NET_XMIT_BYPASS;
 235         for (;;) {
 236                 int result = 0;
 237                 defmap = head->defaults;
 238
 239                 /*
 240                  * Step 2+n. Apply classifier.
 241                  */
 242                 if (!head->filter_list ||
 243                     (result = tc_classify_compat(skb, head->filter_list, &res)) < 0)
 244                         goto fallback;
 245
 246                 cl = (void *)res.class;
 247                 if (!cl) {
 248                         if (TC_H_MAJ(res.classid))
 249                                 cl = cbq_class_lookup(q, res.classid);
 250                         else if ((cl = defmap[res.classid & TC_PRIO_MAX]) == NULL)
 251                                 cl = defmap[TC_PRIO_BESTEFFORT];
 252
 253                         if (cl == NULL)
 254                                 goto fallback;
 255                 }
 256                 if (cl->level >= head->level)
 257                         goto fallback;
 258 #ifdef CONFIG_NET_CLS_ACT
 259                 switch (result) {
 260                 case TC_ACT_QUEUED:
 261                 case TC_ACT_STOLEN:
 262                         *qerr = NET_XMIT_SUCCESS | __NET_XMIT_STOLEN;
 263                 case TC_ACT_SHOT:
 264                         return NULL;
 265                 case TC_ACT_RECLASSIFY:
 266                         return cbq_reclassify(skb, cl);
 267                 }
 268 #endif
 269                 if (cl->level == 0)
 270                         return cl;
 271
 272                 /*
 273                  * Step 3+n. If classifier selected a link sharing class,
 274                  *         apply agency specific classifier.
 275                  *         Repeat this procdure until we hit a leaf node.
 276                  */
 277                 head = cl;
 278         }
 279
 280 fallback:
 281         cl = head;
 282
 283         /*
 284          * Step 4. No success...
 285          */
 286         if (TC_H_MAJ(prio) == 0 &&
 287             !(cl = head->defaults[prio & TC_PRIO_MAX]) &&
 288             !(cl = head->defaults[TC_PRIO_BESTEFFORT]))
 289                 return head;
 290
 291         return cl;
 292 }
 293
 294 /*
 295  * A packet has just been enqueued on the empty class.
 296  * cbq_activate_class adds it to the tail of active class list
 297  * of its priority band.
 298  */
 299
 300 static inline void cbq_activate_class(struct cbq_class *cl)
 301 {
 302         struct cbq_sched_data *q = qdisc_priv(cl->qdisc);
 303         int prio = cl->cpriority;
 304         struct cbq_class *cl_tail;
 305
 306         cl_tail = q->active[prio];
 307         q->active[prio] = cl;
 308
 309         if (cl_tail != NULL) {
 310                 cl->next_alive = cl_tail->next_alive;
 311                 cl_tail->next_alive = cl;
 312         } else {
 313                 cl->next_alive = cl;
 314                 q->activemask |= (1<<prio);
 315         }
 316 }
 317
 318 /*
 319  * Unlink class from active chain.
 320  * Note that this same procedure is done directly in cbq_dequeue*
 321  * during round-robin procedure.
 322  */
 323
 324 static void cbq_deactivate_class(struct cbq_class *this)
 325 {
 326         struct cbq_sched_data *q = qdisc_priv(this->qdisc);
 327         int prio = this->cpriority;
 328         struct cbq_class *cl;
 329         struct cbq_class *cl_prev = q->active[prio];
 330
 331         do {
 332                 cl = cl_prev->next_alive;
 333                 if (cl == this) {
 334                         cl_prev->next_alive = cl->next_alive;
 335                         cl->next_alive = NULL;
 336
 337                         if (cl == q->active[prio]) {
 338                                 q->active[prio] = cl_prev;
 339                                 if (cl == q->active[prio]) {
 340                                         q->active[prio] = NULL;
 341                                         q->activemask &= ~(1<<prio);
 342                                         return;
 343                                 }
 344                         }
 345                         return;
 346                 }
 347         } while ((cl_prev = cl) != q->active[prio]);
 348 }
 349
 350 static void
 351 cbq_mark_toplevel(struct cbq_sched_data *q, struct cbq_class *cl)
 352 {
 353         int toplevel = q->toplevel;
 354
 355         if (toplevel > cl->level && !(qdisc_is_throttled(cl->q))) {
 356                 psched_time_t now;
 357                 psched_tdiff_t incr;
 358
 359                 now = psched_get_time();
 360                 incr = now - q->now_rt;
 361                 now = q->now + incr;
 362
 363                 do {
 364                         if (cl->undertime < now) {
 365                                 q->toplevel = cl->level;
 366                                 return;
 367                         }
 368                 } while ((cl = cl->borrow) != NULL && toplevel > cl->level);
 369         }
 370 }
 371
 372 static int
 373 cbq_enqueue(struct sk_buff *skb, struct Qdisc *sch)
 374 {
 375         struct cbq_sched_data *q = qdisc_priv(sch);
 376         int uninitialized_var(ret);
 377         struct cbq_class *cl = cbq_classify(skb, sch, &ret);
 378
 379 #ifdef CONFIG_NET_CLS_ACT
 380         q->rx_class = cl;
 381 #endif
 382         if (cl == NULL) {
 383                 if (ret & __NET_XMIT_BYPASS)
 384                         sch->qstats.drops++;
 385                 kfree_skb(skb);
 386                 return ret;
 387         }
 388
 389 #ifdef CONFIG_NET_CLS_ACT
 390         cl->q->__parent = sch;
 391 #endif
 392         ret = qdisc_enqueue(skb, cl->q);
 393         if (ret == NET_XMIT_SUCCESS) {
 394                 sch->q.qlen++;
 395                 cbq_mark_toplevel(q, cl);
 396                 if (!cl->next_alive)
 397                         cbq_activate_class(cl);
 398                 return ret;
 399         }
 400
 401         if (net_xmit_drop_count(ret)) {
 402                 sch->qstats.drops++;
 403                 cbq_mark_toplevel(q, cl);
 404                 cl->qstats.drops++;
 405         }
 406         return ret;
 407 }
 408
 409 /* Overlimit actions */
 410
 411 /* TC_CBQ_OVL_CLASSIC: (default) penalize leaf class by adding offtime */
 412
 413 static void cbq_ovl_classic(struct cbq_class *cl)
 414 {
 415         struct cbq_sched_data *q = qdisc_priv(cl->qdisc);
 416         psched_tdiff_t delay = cl->undertime - q->now;
 417
 418         if (!cl->delayed) {
 419                 delay += cl->offtime;
 420
 421                 /*
 422                  * Class goes to sleep, so that it will have no
 423                  * chance to work avgidle. Let's forgive it 8)
 424                  *
 425                  * BTW cbq-2.0 has a crap in this
 426                  * place, apparently they forgot to shift it by cl->ewma_log.
 427                  */
 428                 if (cl->avgidle < 0)
 429                         delay -= (-cl->avgidle) - ((-cl->avgidle) >> cl->ewma_log);
 430                 if (cl->avgidle < cl->minidle)
 431                         cl->avgidle = cl->minidle;
 432                 if (delay <= 0)
 433                         delay = 1;
 434                 cl->undertime = q->now + delay;
 435
 436                 cl->xstats.overactions++;
 437                 cl->delayed = 1;
 438         }
 439         if (q->wd_expires == 0 || q->wd_expires > delay)
 440                 q->wd_expires = delay;
 441
 442         /* Dirty work! We must schedule wakeups based on
 443          * real available rate, rather than leaf rate,
 444          * which may be tiny (even zero).
 445          */
 446         if (q->toplevel == TC_CBQ_MAXLEVEL) {
 447                 struct cbq_class *b;
 448                 psched_tdiff_t base_delay = q->wd_expires;
 449
 450                 for (b = cl->borrow; b; b = b->borrow) {
 451                         delay = b->undertime - q->now;
 452                         if (delay < base_delay) {
 453                                 if (delay <= 0)
 454                                         delay = 1;
 455                                 base_delay = delay;
 456                         }
 457                 }
 458
 459                 q->wd_expires = base_delay;
 460         }
 461 }
 462
 463 /* TC_CBQ_OVL_RCLASSIC: penalize by offtime classes in hierarchy, when
 464  * they go overlimit
 465  */
 466
 467 static void cbq_ovl_rclassic(struct cbq_class *cl)
 468 {
 469         struct cbq_sched_data *q = qdisc_priv(cl->qdisc);
 470         struct cbq_class *this = cl;
 471
 472         do {
 473                 if (cl->level > q->toplevel) {
 474                         cl = NULL;
 475                         break;
 476                 }
 477         } while ((cl = cl->borrow) != NULL);
 478
 479         if (cl == NULL)
 480                 cl = this;
 481         cbq_ovl_classic(cl);
 482 }
 483
 484 /* TC_CBQ_OVL_DELAY: delay until it will go to underlimit */
 485
 486 static void cbq_ovl_delay(struct cbq_class *cl)
 487 {
 488         struct cbq_sched_data *q = qdisc_priv(cl->qdisc);
 489         psched_tdiff_t delay = cl->undertime - q->now;
 490
 491         if (test_bit(__QDISC_STATE_DEACTIVATED,
 492                      &qdisc_root_sleeping(cl->qdisc)->state))
 493                 return;
 494
 495         if (!cl->delayed) {
 496                 psched_time_t sched = q->now;
 497                 ktime_t expires;
 498
 499                 delay += cl->offtime;
 500                 if (cl->avgidle < 0)
 501                         delay -= (-cl->avgidle) - ((-cl->avgidle) >> cl->ewma_log);
 502                 if (cl->avgidle < cl->minidle)
 503                         cl->avgidle = cl->minidle;
 504                 cl->undertime = q->now + delay;
 505
 506                 if (delay > 0) {
 507                         sched += delay + cl->penalty;
 508                         cl->penalized = sched;
 509                         cl->cpriority = TC_CBQ_MAXPRIO;
 510                         q->pmask |= (1<<TC_CBQ_MAXPRIO);
 511
 512                         expires = ns_to_ktime(PSCHED_TICKS2NS(sched));
 513                         if (hrtimer_try_to_cancel(&q->delay_timer) &&
 514                             ktime_to_ns(ktime_sub(
 515                                         hrtimer_get_expires(&q->delay_timer),
 516                                         expires)) > 0)
 517                                 hrtimer_set_expires(&q->delay_timer, expires);
 518                         hrtimer_restart(&q->delay_timer);
 519                         cl->delayed = 1;
 520                         cl->xstats.overactions++;
 521                         return;
 522                 }
 523                 delay = 1;
 524         }
 525         if (q->wd_expires == 0 || q->wd_expires > delay)
 526                 q->wd_expires = delay;
 527 }
 528
 529 /* TC_CBQ_OVL_LOWPRIO: penalize class by lowering its priority band */
 530
 531 static void cbq_ovl_lowprio(struct cbq_class *cl)
 532 {
 533         struct cbq_sched_data *q = qdisc_priv(cl->qdisc);
 534
 535         cl->penalized = q->now + cl->penalty;
 536
 537         if (cl->cpriority != cl->priority2) {
 538                 cl->cpriority = cl->priority2;
 539                 q->pmask |= (1<<cl->cpriority);
 540                 cl->xstats.overactions++;
 541         }
 542         cbq_ovl_classic(cl);
 543 }
 544
 545 /* TC_CBQ_OVL_DROP: penalize class by dropping */
 546
 547 static void cbq_ovl_drop(struct cbq_class *cl)
 548 {
 549         if (cl->q->ops->drop)
 550                 if (cl->q->ops->drop(cl->q))
 551                         cl->qdisc->q.qlen--;
 552         cl->xstats.overactions++;
 553         cbq_ovl_classic(cl);
 554 }
 555
 556 static psched_tdiff_t cbq_undelay_prio(struct cbq_sched_data *q, int prio,
 557                                        psched_time_t now)
 558 {
 559         struct cbq_class *cl;
 560         struct cbq_class *cl_prev = q->active[prio];
 561         psched_time_t sched = now;
 562
 563         if (cl_prev == NULL)
 564                 return 0;
 565
 566         do {
 567                 cl = cl_prev->next_alive;
 568                 if (now - cl->penalized > 0) {
 569                         cl_prev->next_alive = cl->next_alive;
 570                         cl->next_alive = NULL;
 571                         cl->cpriority = cl->priority;
 572                         cl->delayed = 0;
 573                         cbq_activate_class(cl);
 574
 575                         if (cl == q->active[prio]) {
 576                                 q->active[prio] = cl_prev;
 577                                 if (cl == q->active[prio]) {
 578                                         q->active[prio] = NULL;
 579                                         return 0;
 580                                 }
 581                         }
 582
 583                         cl = cl_prev->next_alive;
 584                 } else if (sched - cl->penalized > 0)
 585                         sched = cl->penalized;
 586         } while ((cl_prev = cl) != q->active[prio]);
 587
 588         return sched - now;
 589 }
 590
 591 static enum hrtimer_restart cbq_undelay(struct hrtimer *timer)
 592 {
 593         struct cbq_sched_data *q = container_of(timer, struct cbq_sched_data,
 594                                                 delay_timer);
 595         struct Qdisc *sch = q->watchdog.qdisc;
 596         psched_time_t now;
 597         psched_tdiff_t delay = 0;
 598         unsigned int pmask;
 599
 600         now = psched_get_time();
 601
 602         pmask = q->pmask;
 603         q->pmask = 0;
 604
 605         while (pmask) {
 606                 int prio = ffz(~pmask);
 607                 psched_tdiff_t tmp;
 608
 609                 pmask &= ~(1<<prio);
 610
 611                 tmp = cbq_undelay_prio(q, prio, now);
 612                 if (tmp > 0) {
 613                         q->pmask |= 1<<prio;
 614                         if (tmp < delay || delay == 0)
 615                                 delay = tmp;
 616                 }
 617         }
 618
 619         if (delay) {
 620                 ktime_t time;
 621
 622                 time = ktime_set(0, 0);
 623                 time = ktime_add_ns(time, PSCHED_TICKS2NS(now + delay));
 624                 hrtimer_start(&q->delay_timer, time, HRTIMER_MODE_ABS);
 625         }
 626
 627         qdisc_unthrottled(sch);
 628         __netif_schedule(qdisc_root(sch));
 629         return HRTIMER_NORESTART;
 630 }
 631
 632 #ifdef CONFIG_NET_CLS_ACT
 633 static int cbq_reshape_fail(struct sk_buff *skb, struct Qdisc *child)
 634 {
 635         struct Qdisc *sch = child->__parent;
 636         struct cbq_sched_data *q = qdisc_priv(sch);
 637         struct cbq_class *cl = q->rx_class;
 638
 639         q->rx_class = NULL;
 640
 641         if (cl && (cl = cbq_reclassify(skb, cl)) != NULL) {
 642                 int ret;
 643
 644                 cbq_mark_toplevel(q, cl);
 645
 646                 q->rx_class = cl;
 647                 cl->q->__parent = sch;
 648
 649                 ret = qdisc_enqueue(skb, cl->q);
 650                 if (ret == NET_XMIT_SUCCESS) {
 651                         sch->q.qlen++;
 652                         if (!cl->next_alive)
 653                                 cbq_activate_class(cl);
 654                         return 0;
 655                 }
 656                 if (net_xmit_drop_count(ret))
 657                         sch->qstats.drops++;
 658                 return 0;
 659         }
 660
 661         sch->qstats.drops++;
 662         return -1;
 663 }
 664 #endif
 665
 666 /*
 667  * It is mission critical procedure.
 668  *
 669  * We "regenerate" toplevel cutoff, if transmitting class
 670  * has backlog and it is not regulated. It is not part of
 671  * original CBQ description, but looks more reasonable.
 672  * Probably, it is wrong. This question needs further investigation.
 673  */
 674
 675 static inline void
 676 cbq_update_toplevel(struct cbq_sched_data *q, struct cbq_class *cl,
 677                     struct cbq_class *borrowed)
 678 {
 679         if (cl && q->toplevel >= borrowed->level) {
 680                 if (cl->q->q.qlen > 1) {
 681                         do {
 682                                 if (borrowed->undertime == PSCHED_PASTPERFECT) {
 683                                         q->toplevel = borrowed->level;
 684                                         return;
 685                                 }
 686                         } while ((borrowed = borrowed->borrow) != NULL);
 687                 }
 688 #if 0
 689         /* It is not necessary now. Uncommenting it
 690            will save CPU cycles, but decrease fairness.
 691          */
 692                 q->toplevel = TC_CBQ_MAXLEVEL;
 693 #endif
 694         }
 695 }
 696
 697 static void
 698 cbq_update(struct cbq_sched_data *q)
 699 {
 700         struct cbq_class *this = q->tx_class;
 701         struct cbq_class *cl = this;
 702         int len = q->tx_len;
 703
 704         q->tx_class = NULL;
 705
 706         for ( ; cl; cl = cl->share) {
 707                 long avgidle = cl->avgidle;
 708                 long idle;
 709
 710                 cl->bstats.packets++;
 711                 cl->bstats.bytes += len;
 712
 713                 /*
 714                  * (now - last) is total time between packet right edges.
 715                  * (last_pktlen/rate) is "virtual" busy time, so that
 716                  *
 717                  *      idle = (now - last) - last_pktlen/rate
 718                  */
 719
 720                 idle = q->now - cl->last;
 721                 if ((unsigned long)idle > 128*1024*1024) {
 722                         avgidle = cl->maxidle;
 723                 } else {
 724                         idle -= L2T(cl, len);
 725
 726                 /* true_avgidle := (1-W)*true_avgidle + W*idle,
 727                  * where W=2^{-ewma_log}. But cl->avgidle is scaled:
 728                  * cl->avgidle == true_avgidle/W,
 729                  * hence:
 730                  */
 731                         avgidle += idle - (avgidle>>cl->ewma_log);
 732                 }
 733
 734                 if (avgidle <= 0) {
 735                         /* Overlimit or at-limit */
 736
 737                         if (avgidle < cl->minidle)
 738                                 avgidle = cl->minidle;
 739
 740                         cl->avgidle = avgidle;
 741
 742                         /* Calculate expected time, when this class
 743                          * will be allowed to send.
 744                          * It will occur, when:
 745                          * (1-W)*true_avgidle + W*delay = 0, i.e.
 746                          * idle = (1/W - 1)*(-true_avgidle)
 747                          * or
 748                          * idle = (1 - W)*(-cl->avgidle);
 749                          */
 750                         idle = (-avgidle) - ((-avgidle) >> cl->ewma_log);
 751
 752                         /*
 753                          * That is not all.
 754                          * To maintain the rate allocated to the class,
 755                          * we add to undertime virtual clock,
 756                          * necessary to complete transmitted packet.
 757                          * (len/phys_bandwidth has been already passed
 758                          * to the moment of cbq_update)
 759                          */
 760
 761                         idle -= L2T(&q->link, len);
 762                         idle += L2T(cl, len);
 763
 764                         cl->undertime = q->now + idle;
 765                 } else {
 766                         /* Underlimit */
 767
 768                         cl->undertime = PSCHED_PASTPERFECT;
 769                         if (avgidle > cl->maxidle)
 770                                 cl->avgidle = cl->maxidle;
 771                         else
 772                                 cl->avgidle = avgidle;
 773                 }
 774                 cl->last = q->now;
 775         }
 776
 777         cbq_update_toplevel(q, this, q->tx_borrowed);
 778 }
 779
 780 static inline struct cbq_class *
 781 cbq_under_limit(struct cbq_class *cl)
 782 {
 783         struct cbq_sched_data *q = qdisc_priv(cl->qdisc);
 784         struct cbq_class *this_cl = cl;
 785
 786         if (cl->tparent == NULL)
 787                 return cl;
 788
 789         if (cl->undertime == PSCHED_PASTPERFECT || q->now >= cl->undertime) {
 790                 cl->delayed = 0;
 791                 return cl;
 792         }
 793
 794         do {
 795                 /* It is very suspicious place. Now overlimit
 796                  * action is generated for not bounded classes
 797                  * only if link is completely congested.
 798                  * Though it is in agree with ancestor-only paradigm,
 799                  * it looks very stupid. Particularly,
 800                  * it means that this chunk of code will either
 801                  * never be called or result in strong amplification
 802                  * of burstiness. Dangerous, silly, and, however,
 803                  * no another solution exists.
 804                  */
 805                 cl = cl->borrow;
 806                 if (!cl) {
 807                         this_cl->qstats.overlimits++;
 808                         this_cl->overlimit(this_cl);
 809                         return NULL;
 810                 }
 811                 if (cl->level > q->toplevel)
 812                         return NULL;
 813         } while (cl->undertime != PSCHED_PASTPERFECT && q->now < cl->undertime);
 814
 815         cl->delayed = 0;
 816         return cl;
 817 }
 818
 819 static inline struct sk_buff *
 820 cbq_dequeue_prio(struct Qdisc *sch, int prio)
 821 {
 822         struct cbq_sched_data *q = qdisc_priv(sch);
 823         struct cbq_class *cl_tail, *cl_prev, *cl;
 824         struct sk_buff *skb;
 825         int deficit;
 826
 827         cl_tail = cl_prev = q->active[prio];
 828         cl = cl_prev->next_alive;
 829
 830         do {
 831                 deficit = 0;
 832
 833                 /* Start round */
 834                 do {
 835                         struct cbq_class *borrow = cl;
 836
 837                         if (cl->q->q.qlen &&
 838                             (borrow = cbq_under_limit(cl)) == NULL)
 839                                 goto skip_class;
 840
 841                         if (cl->deficit <= 0) {
 842                                 /* Class exhausted its allotment per
 843                                  * this round. Switch to the next one.
 844                                  */
 845                                 deficit = 1;
 846                                 cl->deficit += cl->quantum;
 847                                 goto next_class;
 848                         }
 849
 850                         skb = cl->q->dequeue(cl->q);
 851
 852                         /* Class did not give us any skb :-(
 853                          * It could occur even if cl->q->q.qlen != 0
 854                          * f.e. if cl->q == "tbf"
 855                          */
 856                         if (skb == NULL)
 857                                 goto skip_class;
 858
 859                         cl->deficit -= qdisc_pkt_len(skb);
 860                         q->tx_class = cl;
 861                         q->tx_borrowed = borrow;
 862                         if (borrow != cl) {
 863 #ifndef CBQ_XSTATS_BORROWS_BYTES
 864                                 borrow->xstats.borrows++;
 865                                 cl->xstats.borrows++;
 866 #else
 867                                 borrow->xstats.borrows += qdisc_pkt_len(skb);
 868                                 cl->xstats.borrows += qdisc_pkt_len(skb);
 869 #endif
 870                         }
 871                         q->tx_len = qdisc_pkt_len(skb);
 872
 873                         if (cl->deficit <= 0) {
 874                                 q->active[prio] = cl;
 875                                 cl = cl->next_alive;
 876                                 cl->deficit += cl->quantum;
 877                         }
 878                         return skb;
 879
 880 skip_class:
 881                         if (cl->q->q.qlen == 0 || prio != cl->cpriority) {
 882                                 /* Class is empty or penalized.
 883                                  * Unlink it from active chain.
 884                                  */
 885                                 cl_prev->next_alive = cl->next_alive;
 886                                 cl->next_alive = NULL;
 887
 888                                 /* Did cl_tail point to it? */
 889                                 if (cl == cl_tail) {
 890                                         /* Repair it! */
 891                                         cl_tail = cl_prev;
 892
 893                                         /* Was it the last class in this band? */
 894                                         if (cl == cl_tail) {
 895                                                 /* Kill the band! */
 896                                                 q->active[prio] = NULL;
 897                                                 q->activemask &= ~(1<<prio);
 898                                                 if (cl->q->q.qlen)
 899                                                         cbq_activate_class(cl);
 900                                                 return NULL;
 901                                         }
 902
 903                                         q->active[prio] = cl_tail;
 904                                 }
 905                                 if (cl->q->q.qlen)
 906                                         cbq_activate_class(cl);
 907
 908                                 cl = cl_prev;
 909                         }
 910
 911 next_class:
 912                         cl_prev = cl;
 913                         cl = cl->next_alive;
 914                 } while (cl_prev != cl_tail);
 915         } while (deficit);
 916
 917         q->active[prio] = cl_prev;
 918
 919         return NULL;
 920 }
 921
 922 static inline struct sk_buff *
 923 cbq_dequeue_1(struct Qdisc *sch)
 924 {
 925         struct cbq_sched_data *q = qdisc_priv(sch);
 926         struct sk_buff *skb;
 927         unsigned int activemask;
 928
 929         activemask = q->activemask & 0xFF;
 930         while (activemask) {
 931                 int prio = ffz(~activemask);
 932                 activemask &= ~(1<<prio);
 933                 skb = cbq_dequeue_prio(sch, prio);
 934                 if (skb)
 935                         return skb;
 936         }
 937         return NULL;
 938 }
 939
 940 static struct sk_buff *
 941 cbq_dequeue(struct Qdisc *sch)
 942 {
 943         struct sk_buff *skb;
 944         struct cbq_sched_data *q = qdisc_priv(sch);
 945         psched_time_t now;
 946         psched_tdiff_t incr;
 947
 948         now = psched_get_time();
 949         incr = now - q->now_rt;
 950
 951         if (q->tx_class) {
 952                 psched_tdiff_t incr2;
 953                 /* Time integrator. We calculate EOS time
 954                  * by adding expected packet transmission time.
 955                  * If real time is greater, we warp artificial clock,
 956                  * so that:
 957                  *
 958                  * cbq_time = max(real_time, work);
 959                  */
 960                 incr2 = L2T(&q->link, q->tx_len);
 961                 q->now += incr2;
 962                 cbq_update(q);
 963                 if ((incr -= incr2) < 0)
 964                         incr = 0;
 965                 q->now += incr;
 966         } else {
 967                 if (now > q->now)
 968                         q->now = now;
 969         }
 970         q->now_rt = now;
 971
 972         for (;;) {
 973                 q->wd_expires = 0;
 974
 975                 skb = cbq_dequeue_1(sch);
 976                 if (skb) {
 977                         qdisc_bstats_update(sch, skb);
 978                         sch->q.qlen--;
 979                         qdisc_unthrottled(sch);
 980                         return skb;
 981                 }
 982
 983                 /* All the classes are overlimit.
 984                  *
 985                  * It is possible, if:
 986                  *
 987                  * 1. Scheduler is empty.
 988                  * 2. Toplevel cutoff inhibited borrowing.
 989                  * 3. Root class is overlimit.
 990                  *
 991                  * Reset 2d and 3d conditions and retry.
 992                  *
 993                  * Note, that NS and cbq-2.0 are buggy, peeking
 994                  * an arbitrary class is appropriate for ancestor-only
 995                  * sharing, but not for toplevel algorithm.
 996                  *
 997                  * Our version is better, but slower, because it requires
 998                  * two passes, but it is unavoidable with top-level sharing.
 999                  */
1000
1001                 if (q->toplevel == TC_CBQ_MAXLEVEL &&
1002                     q->link.undertime == PSCHED_PASTPERFECT)
1003                         break;
1004
1005                 q->toplevel = TC_CBQ_MAXLEVEL;
1006                 q->link.undertime = PSCHED_PASTPERFECT;
1007         }
1008
1009         /* No packets in scheduler or nobody wants to give them to us :-(
1010          * Sigh... start watchdog timer in the last case.
1011          */
1012
1013         if (sch->q.qlen) {
1014                 sch->qstats.overlimits++;
1015                 if (q->wd_expires)
1016                         qdisc_watchdog_schedule(&q->watchdog,
1017                                                 now + q->wd_expires);
1018         }
1019         return NULL;
1020 }
1021
1022 /* CBQ class maintanance routines */
1023
1024 static void cbq_adjust_levels(struct cbq_class *this)
1025 {
1026         if (this == NULL)
1027                 return;
1028
1029         do {
1030                 int level = 0;
1031                 struct cbq_class *cl;
1032
1033                 cl = this->children;
1034                 if (cl) {
1035                         do {
1036                                 if (cl->level > level)
1037                                         level = cl->level;
1038                         } while ((cl = cl->sibling) != this->children);
1039                 }
1040                 this->level = level + 1;
1041         } while ((this = this->tparent) != NULL);
1042 }
1043
1044 static void cbq_normalize_quanta(struct cbq_sched_data *q, int prio)
1045 {
1046         struct cbq_class *cl;
1047         unsigned int h;
1048
1049         if (q->quanta[prio] == 0)
1050                 return;
1051
1052         for (h = 0; h < q->clhash.hashsize; h++) {
1053                 hlist_for_each_entry(cl, &q->clhash.hash[h], common.hnode) {
1054                         /* BUGGGG... Beware! This expression suffer of
1055                          * arithmetic overflows!
1056                          */
1057                         if (cl->priority == prio) {
1058                                 cl->quantum = (cl->weight*cl->allot*q->nclasses[prio])/
1059                                         q->quanta[prio];
1060                         }
1061                         if (cl->quantum <= 0 ||
1062                             cl->quantum > 32*qdisc_dev(cl->qdisc)->mtu) {
1063                                 pr_warning("CBQ: class %08x has bad quantum==%ld, repaired.\n",
1064                                            cl->common.classid, cl->quantum);
1065                                 cl->quantum = qdisc_dev(cl->qdisc)->mtu/2 + 1;
1066                         }
1067                 }
1068         }
1069 }
1070
1071 static void cbq_sync_defmap(struct cbq_class *cl)
1072 {
1073         struct cbq_sched_data *q = qdisc_priv(cl->qdisc);
1074         struct cbq_class *split = cl->split;
1075         unsigned int h;
1076         int i;
1077
1078         if (split == NULL)
1079                 return;
1080
1081         for (i = 0; i <= TC_PRIO_MAX; i++) {
1082                 if (split->defaults[i] == cl && !(cl->defmap & (1<<i)))
1083                         split->defaults[i] = NULL;
1084         }
1085
1086         for (i = 0; i <= TC_PRIO_MAX; i++) {
1087                 int level = split->level;
1088
1089                 if (split->defaults[i])
1090                         continue;
1091
1092                 for (h = 0; h < q->clhash.hashsize; h++) {
1093                         struct cbq_class *c;
1094
1095                         hlist_for_each_entry(c, &q->clhash.hash[h],
1096                                              common.hnode) {
1097                                 if (c->split == split && c->level < level &&
1098                                     c->defmap & (1<<i)) {
1099                                         split->defaults[i] = c;
1100                                         level = c->level;
1101                                 }
1102                         }
1103                 }
1104         }
1105 }
1106
1107 static void cbq_change_defmap(struct cbq_class *cl, u32 splitid, u32 def, u32 mask)
1108 {
1109         struct cbq_class *split = NULL;
1110
1111         if (splitid == 0) {
1112                 split = cl->split;
1113                 if (!split)
1114                         return;
1115                 splitid = split->common.classid;
1116         }
1117
1118         if (split == NULL || split->common.classid != splitid) {
1119                 for (split = cl->tparent; split; split = split->tparent)
1120                         if (split->common.classid == splitid)
1121                                 break;
1122         }
1123
1124         if (split == NULL)
1125                 return;
1126
1127         if (cl->split != split) {
1128                 cl->defmap = 0;
1129                 cbq_sync_defmap(cl);
1130                 cl->split = split;
1131                 cl->defmap = def & mask;
1132         } else
1133                 cl->defmap = (cl->defmap & ~mask) | (def & mask);
1134
1135         cbq_sync_defmap(cl);
1136 }
1137
1138 static void cbq_unlink_class(struct cbq_class *this)
1139 {
1140         struct cbq_class *cl, **clp;
1141         struct cbq_sched_data *q = qdisc_priv(this->qdisc);
1142
1143         qdisc_class_hash_remove(&q->clhash, &this->common);
1144
1145         if (this->tparent) {
1146                 clp = &this->sibling;
1147                 cl = *clp;
1148                 do {
1149                         if (cl == this) {
1150                                 *clp = cl->sibling;
1151                                 break;
1152                         }
1153                         clp = &cl->sibling;
1154                 } while ((cl = *clp) != this->sibling);
1155
1156                 if (this->tparent->children == this) {
1157                         this->tparent->children = this->sibling;
1158                         if (this->sibling == this)
1159                                 this->tparent->children = NULL;
1160                 }
1161         } else {
1162                 WARN_ON(this->sibling != this);
1163         }
1164 }
1165
1166 static void cbq_link_class(struct cbq_class *this)
1167 {
1168         struct cbq_sched_data *q = qdisc_priv(this->qdisc);
1169         struct cbq_class *parent = this->tparent;
1170
1171         this->sibling = this;
1172         qdisc_class_hash_insert(&q->clhash, &this->common);
1173
1174         if (parent == NULL)
1175                 return;
1176
1177         if (parent->children == NULL) {
1178                 parent->children = this;
1179         } else {
1180                 this->sibling = parent->children->sibling;
1181                 parent->children->sibling = this;
1182         }
1183 }
1184
1185 static unsigned int cbq_drop(struct Qdisc *sch)
1186 {
1187         struct cbq_sched_data *q = qdisc_priv(sch);
1188         struct cbq_class *cl, *cl_head;
1189         int prio;
1190         unsigned int len;
1191
1192         for (prio = TC_CBQ_MAXPRIO; prio >= 0; prio--) {
1193                 cl_head = q->active[prio];
1194                 if (!cl_head)
1195                         continue;
1196
1197                 cl = cl_head;
1198                 do {
1199                         if (cl->q->ops->drop && (len = cl->q->ops->drop(cl->q))) {
1200                                 sch->q.qlen--;
1201                                 if (!cl->q->q.qlen)
1202                                         cbq_deactivate_class(cl);
1203                                 return len;
1204                         }
1205                 } while ((cl = cl->next_alive) != cl_head);
1206         }
1207         return 0;
1208 }
1209
1210 static void
1211 cbq_reset(struct Qdisc *sch)
1212 {
1213         struct cbq_sched_data *q = qdisc_priv(sch);
1214         struct cbq_class *cl;
1215         int prio;
1216         unsigned int h;
1217
1218         q->activemask = 0;
1219         q->pmask = 0;
1220         q->tx_class = NULL;
1221         q->tx_borrowed = NULL;
1222         qdisc_watchdog_cancel(&q->watchdog);
1223         hrtimer_cancel(&q->delay_timer);
1224         q->toplevel = TC_CBQ_MAXLEVEL;
1225         q->now = psched_get_time();
1226         q->now_rt = q->now;
1227
1228         for (prio = 0; prio <= TC_CBQ_MAXPRIO; prio++)
1229                 q->active[prio] = NULL;
1230
1231         for (h = 0; h < q->clhash.hashsize; h++) {
1232                 hlist_for_each_entry(cl, &q->clhash.hash[h], common.hnode) {
1233                         qdisc_reset(cl->q);
1234
1235                         cl->next_alive = NULL;
1236                         cl->undertime = PSCHED_PASTPERFECT;
1237                         cl->avgidle = cl->maxidle;
1238                         cl->deficit = cl->quantum;
1239                         cl->cpriority = cl->priority;
1240                 }
1241         }
1242         sch->q.qlen = 0;
1243 }
1244
1245
1246 static int cbq_set_lss(struct cbq_class *cl, struct tc_cbq_lssopt *lss)
1247 {
1248         if (lss->change & TCF_CBQ_LSS_FLAGS) {
1249                 cl->share = (lss->flags & TCF_CBQ_LSS_ISOLATED) ? NULL : cl->tparent;
1250                 cl->borrow = (lss->flags & TCF_CBQ_LSS_BOUNDED) ? NULL : cl->tparent;
1251         }
1252         if (lss->change & TCF_CBQ_LSS_EWMA)
1253                 cl->ewma_log = lss->ewma_log;
1254         if (lss->change & TCF_CBQ_LSS_AVPKT)
1255                 cl->avpkt = lss->avpkt;
1256         if (lss->change & TCF_CBQ_LSS_MINIDLE)
1257                 cl->minidle = -(long)lss->minidle;
1258         if (lss->change & TCF_CBQ_LSS_MAXIDLE) {
1259                 cl->maxidle = lss->maxidle;
1260                 cl->avgidle = lss->maxidle;
1261         }
1262         if (lss->change & TCF_CBQ_LSS_OFFTIME)
1263                 cl->offtime = lss->offtime;
1264         return 0;
1265 }
1266
1267 static void cbq_rmprio(struct cbq_sched_data *q, struct cbq_class *cl)
1268 {
1269         q->nclasses[cl->priority]--;
1270         q->quanta[cl->priority] -= cl->weight;
1271         cbq_normalize_quanta(q, cl->priority);
1272 }
1273
1274 static void cbq_addprio(struct cbq_sched_data *q, struct cbq_class *cl)
1275 {
1276         q->nclasses[cl->priority]++;
1277         q->quanta[cl->priority] += cl->weight;
1278         cbq_normalize_quanta(q, cl->priority);
1279 }
1280
1281 static int cbq_set_wrr(struct cbq_class *cl, struct tc_cbq_wrropt *wrr)
1282 {
1283         struct cbq_sched_data *q = qdisc_priv(cl->qdisc);
1284
1285         if (wrr->allot)
1286                 cl->allot = wrr->allot;
1287         if (wrr->weight)
1288                 cl->weight = wrr->weight;
1289         if (wrr->priority) {
1290                 cl->priority = wrr->priority - 1;
1291                 cl->cpriority = cl->priority;
1292                 if (cl->priority >= cl->priority2)
1293                         cl->priority2 = TC_CBQ_MAXPRIO - 1;
1294         }
1295
1296         cbq_addprio(q, cl);
1297         return 0;
1298 }
1299
1300 static int cbq_set_overlimit(struct cbq_class *cl, struct tc_cbq_ovl *ovl)
1301 {
1302         switch (ovl->strategy) {
1303         case TC_CBQ_OVL_CLASSIC:
1304                 cl->overlimit = cbq_ovl_classic;
1305                 break;
1306         case TC_CBQ_OVL_DELAY:
1307                 cl->overlimit = cbq_ovl_delay;
1308                 break;
1309         case TC_CBQ_OVL_LOWPRIO:
1310                 if (ovl->priority2 - 1 >= TC_CBQ_MAXPRIO ||
1311                     ovl->priority2 - 1 <= cl->priority)
1312                         return -EINVAL;
1313                 cl->priority2 = ovl->priority2 - 1;
1314                 cl->overlimit = cbq_ovl_lowprio;
1315                 break;
1316         case TC_CBQ_OVL_DROP:
1317                 cl->overlimit = cbq_ovl_drop;
1318                 break;
1319         case TC_CBQ_OVL_RCLASSIC:
1320                 cl->overlimit = cbq_ovl_rclassic;
1321                 break;
1322         default:
1323                 return -EINVAL;
1324         }
1325         cl->penalty = ovl->penalty;
1326         return 0;
1327 }
1328
1329 #ifdef CONFIG_NET_CLS_ACT
1330 static int cbq_set_police(struct cbq_class *cl, struct tc_cbq_police *p)
1331 {
1332         cl->police = p->police;
1333
1334         if (cl->q->handle) {
1335                 if (p->police == TC_POLICE_RECLASSIFY)
1336                         cl->q->reshape_fail = cbq_reshape_fail;
1337                 else
1338                         cl->q->reshape_fail = NULL;
1339         }
1340         return 0;
1341 }
1342 #endif
1343
1344 static int cbq_set_fopt(struct cbq_class *cl, struct tc_cbq_fopt *fopt)
1345 {
1346         cbq_change_defmap(cl, fopt->split, fopt->defmap, fopt->defchange);
1347         return 0;
1348 }
1349
1350 static const struct nla_policy cbq_policy[TCA_CBQ_MAX + 1] = {
1351         [TCA_CBQ_LSSOPT]        = { .len = sizeof(struct tc_cbq_lssopt) },
1352         [TCA_CBQ_WRROPT]        = { .len = sizeof(struct tc_cbq_wrropt) },
1353         [TCA_CBQ_FOPT]          = { .len = sizeof(struct tc_cbq_fopt) },
1354         [TCA_CBQ_OVL_STRATEGY]  = { .len = sizeof(struct tc_cbq_ovl) },
1355         [TCA_CBQ_RATE]          = { .len = sizeof(struct tc_ratespec) },
1356         [TCA_CBQ_RTAB]          = { .type = NLA_BINARY, .len = TC_RTAB_SIZE },
1357         [TCA_CBQ_POLICE]        = { .len = sizeof(struct tc_cbq_police) },
1358 };
1359
1360 static int cbq_init(struct Qdisc *sch, struct nlattr *opt)
1361 {
1362         struct cbq_sched_data *q = qdisc_priv(sch);
1363         struct nlattr *tb[TCA_CBQ_MAX + 1];
1364         struct tc_ratespec *r;
1365         int err;
1366
1367         err = nla_parse_nested(tb, TCA_CBQ_MAX, opt, cbq_policy);
1368         if (err < 0)
1369                 return err;
1370
1371         if (tb[TCA_CBQ_RTAB] == NULL || tb[TCA_CBQ_RATE] == NULL)
1372                 return -EINVAL;
1373
1374         r = nla_data(tb[TCA_CBQ_RATE]);
1375
1376         if ((q->link.R_tab = qdisc_get_rtab(r, tb[TCA_CBQ_RTAB])) == NULL)
1377                 return -EINVAL;
1378
1379         err = qdisc_class_hash_init(&q->clhash);
1380         if (err < 0)
1381                 goto put_rtab;
1382
1383         q->link.refcnt = 1;
1384         q->link.sibling = &q->link;
1385         q->link.common.classid = sch->handle;
1386         q->link.qdisc = sch;
1387         q->link.q = qdisc_create_dflt(sch->dev_queue, &pfifo_qdisc_ops,
1388                                       sch->handle);
1389         if (!q->link.q)
1390                 q->link.q = &noop_qdisc;
1391
1392         q->link.priority = TC_CBQ_MAXPRIO - 1;
1393         q->link.priority2 = TC_CBQ_MAXPRIO - 1;
1394         q->link.cpriority = TC_CBQ_MAXPRIO - 1;
1395         q->link.ovl_strategy = TC_CBQ_OVL_CLASSIC;
1396         q->link.overlimit = cbq_ovl_classic;
1397         q->link.allot = psched_mtu(qdisc_dev(sch));
1398         q->link.quantum = q->link.allot;
1399         q->link.weight = q->link.R_tab->rate.rate;
1400
1401         q->link.ewma_log = TC_CBQ_DEF_EWMA;
1402         q->link.avpkt = q->link.allot/2;
1403         q->link.minidle = -0x7FFFFFFF;
1404
1405         qdisc_watchdog_init(&q->watchdog, sch);
1406         hrtimer_init(&q->delay_timer, CLOCK_MONOTONIC, HRTIMER_MODE_ABS);
1407         q->delay_timer.function = cbq_undelay;
1408         q->toplevel = TC_CBQ_MAXLEVEL;
1409         q->now = psched_get_time();
1410         q->now_rt = q->now;
1411
1412         cbq_link_class(&q->link);
1413
1414         if (tb[TCA_CBQ_LSSOPT])
1415                 cbq_set_lss(&q->link, nla_data(tb[TCA_CBQ_LSSOPT]));
1416
1417         cbq_addprio(q, &q->link);
1418         return 0;
1419
1420 put_rtab:
1421         qdisc_put_rtab(q->link.R_tab);
1422         return err;
1423 }
1424
1425 static int cbq_dump_rate(struct sk_buff *skb, struct cbq_class *cl)
1426 {
1427         unsigned char *b = skb_tail_pointer(skb);
1428
1429         if (nla_put(skb, TCA_CBQ_RATE, sizeof(cl->R_tab->rate), &cl->R_tab->rate))
1430                 goto nla_put_failure;
1431         return skb->len;
1432
1433 nla_put_failure:
1434         nlmsg_trim(skb, b);
1435         return -1;
1436 }
1437
1438 static int cbq_dump_lss(struct sk_buff *skb, struct cbq_class *cl)
1439 {
1440         unsigned char *b = skb_tail_pointer(skb);
1441         struct tc_cbq_lssopt opt;
1442
1443         opt.flags = 0;
1444         if (cl->borrow == NULL)
1445                 opt.flags |= TCF_CBQ_LSS_BOUNDED;
1446         if (cl->share == NULL)
1447                 opt.flags |= TCF_CBQ_LSS_ISOLATED;
1448         opt.ewma_log = cl->ewma_log;
1449         opt.level = cl->level;
1450         opt.avpkt = cl->avpkt;
1451         opt.maxidle = cl->maxidle;
1452         opt.minidle = (u32)(-cl->minidle);
1453         opt.offtime = cl->offtime;
1454         opt.change = ~0;
1455         if (nla_put(skb, TCA_CBQ_LSSOPT, sizeof(opt), &opt))
1456                 goto nla_put_failure;
1457         return skb->len;
1458
1459 nla_put_failure:
1460         nlmsg_trim(skb, b);
1461         return -1;
1462 }
1463
1464 static int cbq_dump_wrr(struct sk_buff *skb, struct cbq_class *cl)
1465 {
1466         unsigned char *b = skb_tail_pointer(skb);
1467         struct tc_cbq_wrropt opt;
1468
1469         memset(&opt, 0, sizeof(opt));
1470         opt.flags = 0;
1471         opt.allot = cl->allot;
1472         opt.priority = cl->priority + 1;
1473         opt.cpriority = cl->cpriority + 1;
1474         opt.weight = cl->weight;
1475         if (nla_put(skb, TCA_CBQ_WRROPT, sizeof(opt), &opt))
1476                 goto nla_put_failure;
1477         return skb->len;
1478
1479 nla_put_failure:
1480         nlmsg_trim(skb, b);
1481         return -1;
1482 }
1483
1484 static int cbq_dump_ovl(struct sk_buff *skb, struct cbq_class *cl)
1485 {
1486         unsigned char *b = skb_tail_pointer(skb);
1487         struct tc_cbq_ovl opt;
1488
1489         opt.strategy = cl->ovl_strategy;
1490         opt.priority2 = cl->priority2 + 1;
1491         opt.pad = 0;
1492         opt.penalty = cl->penalty;
1493         if (nla_put(skb, TCA_CBQ_OVL_STRATEGY, sizeof(opt), &opt))
1494                 goto nla_put_failure;
1495         return skb->len;
1496
1497 nla_put_failure:
1498         nlmsg_trim(skb, b);
1499         return -1;
1500 }
1501
1502 static int cbq_dump_fopt(struct sk_buff *skb, struct cbq_class *cl)
1503 {
1504         unsigned char *b = skb_tail_pointer(skb);
1505         struct tc_cbq_fopt opt;
1506
1507         if (cl->split || cl->defmap) {
1508                 opt.split = cl->split ? cl->split->common.classid : 0;
1509                 opt.defmap = cl->defmap;
1510                 opt.defchange = ~0;
1511                 if (nla_put(skb, TCA_CBQ_FOPT, sizeof(opt), &opt))
1512                         goto nla_put_failure;
1513         }
1514         return skb->len;
1515
1516 nla_put_failure:
1517         nlmsg_trim(skb, b);
1518         return -1;
1519 }
1520
1521 #ifdef CONFIG_NET_CLS_ACT
1522 static int cbq_dump_police(struct sk_buff *skb, struct cbq_class *cl)
1523 {
1524         unsigned char *b = skb_tail_pointer(skb);
1525         struct tc_cbq_police opt;
1526
1527         if (cl->police) {
1528                 opt.police = cl->police;
1529                 opt.__res1 = 0;
1530                 opt.__res2 = 0;
1531                 if (nla_put(skb, TCA_CBQ_POLICE, sizeof(opt), &opt))
1532                         goto nla_put_failure;
1533         }
1534         return skb->len;
1535
1536 nla_put_failure:
1537         nlmsg_trim(skb, b);
1538         return -1;
1539 }
1540 #endif
1541
1542 static int cbq_dump_attr(struct sk_buff *skb, struct cbq_class *cl)
1543 {
1544         if (cbq_dump_lss(skb, cl) < 0 ||
1545             cbq_dump_rate(skb, cl) < 0 ||
1546             cbq_dump_wrr(skb, cl) < 0 ||
1547             cbq_dump_ovl(skb, cl) < 0 ||
1548 #ifdef CONFIG_NET_CLS_ACT
1549             cbq_dump_police(skb, cl) < 0 ||
1550 #endif
1551             cbq_dump_fopt(skb, cl) < 0)
1552                 return -1;
1553         return 0;
1554 }
1555
1556 static int cbq_dump(struct Qdisc *sch, struct sk_buff *skb)
1557 {
1558         struct cbq_sched_data *q = qdisc_priv(sch);
1559         struct nlattr *nest;
1560
1561         nest = nla_nest_start(skb, TCA_OPTIONS);
1562         if (nest == NULL)
1563                 goto nla_put_failure;
1564         if (cbq_dump_attr(skb, &q->link) < 0)
1565                 goto nla_put_failure;
1566         nla_nest_end(skb, nest);
1567         return skb->len;
1568
1569 nla_put_failure:
1570         nla_nest_cancel(skb, nest);
1571         return -1;
1572 }
1573
1574 static int
1575 cbq_dump_stats(struct Qdisc *sch, struct gnet_dump *d)
1576 {
1577         struct cbq_sched_data *q = qdisc_priv(sch);
1578
1579         q->link.xstats.avgidle = q->link.avgidle;
1580         return gnet_stats_copy_app(d, &q->link.xstats, sizeof(q->link.xstats));
1581 }
1582
1583 static int
1584 cbq_dump_class(struct Qdisc *sch, unsigned long arg,
1585                struct sk_buff *skb, struct tcmsg *tcm)
1586 {
1587         struct cbq_class *cl = (struct cbq_class *)arg;
1588         struct nlattr *nest;
1589
1590         if (cl->tparent)
1591                 tcm->tcm_parent = cl->tparent->common.classid;
1592         else
1593                 tcm->tcm_parent = TC_H_ROOT;
1594         tcm->tcm_handle = cl->common.classid;
1595         tcm->tcm_info = cl->q->handle;
1596
1597         nest = nla_nest_start(skb, TCA_OPTIONS);
1598         if (nest == NULL)
1599                 goto nla_put_failure;
1600         if (cbq_dump_attr(skb, cl) < 0)
1601                 goto nla_put_failure;
1602         nla_nest_end(skb, nest);
1603         return skb->len;
1604
1605 nla_put_failure:
1606         nla_nest_cancel(skb, nest);
1607         return -1;
1608 }
1609
1610 static int
1611 cbq_dump_class_stats(struct Qdisc *sch, unsigned long arg,
1612         struct gnet_dump *d)
1613 {
1614         struct cbq_sched_data *q = qdisc_priv(sch);
1615         struct cbq_class *cl = (struct cbq_class *)arg;
1616
1617         cl->qstats.qlen = cl->q->q.qlen;
1618         cl->xstats.avgidle = cl->avgidle;
1619         cl->xstats.undertime = 0;
1620
1621         if (cl->undertime != PSCHED_PASTPERFECT)
1622                 cl->xstats.undertime = cl->undertime - q->now;
1623
1624         if (gnet_stats_copy_basic(d, &cl->bstats) < 0 ||
1625             gnet_stats_copy_rate_est(d, &cl->bstats, &cl->rate_est) < 0 ||
1626             gnet_stats_copy_queue(d, &cl->qstats) < 0)
1627                 return -1;
1628
1629         return gnet_stats_copy_app(d, &cl->xstats, sizeof(cl->xstats));
1630 }
1631
1632 static int cbq_graft(struct Qdisc *sch, unsigned long arg, struct Qdisc *new,
1633                      struct Qdisc **old)
1634 {
1635         struct cbq_class *cl = (struct cbq_class *)arg;
1636
1637         if (new == NULL) {
1638                 new = qdisc_create_dflt(sch->dev_queue,
1639                                         &pfifo_qdisc_ops, cl->common.classid);
1640                 if (new == NULL)
1641                         return -ENOBUFS;
1642         } else {
1643 #ifdef CONFIG_NET_CLS_ACT
1644                 if (cl->police == TC_POLICE_RECLASSIFY)
1645                         new->reshape_fail = cbq_reshape_fail;
1646 #endif
1647         }
1648         sch_tree_lock(sch);
1649         *old = cl->q;
1650         cl->q = new;
1651         qdisc_tree_decrease_qlen(*old, (*old)->q.qlen);
1652         qdisc_reset(*old);
1653         sch_tree_unlock(sch);
1654
1655         return 0;
1656 }
1657
1658 static struct Qdisc *cbq_leaf(struct Qdisc *sch, unsigned long arg)
1659 {
1660         struct cbq_class *cl = (struct cbq_class *)arg;
1661
1662         return cl->q;
1663 }
1664
1665 static void cbq_qlen_notify(struct Qdisc *sch, unsigned long arg)
1666 {
1667         struct cbq_class *cl = (struct cbq_class *)arg;
1668
1669         if (cl->q->q.qlen == 0)
1670                 cbq_deactivate_class(cl);
1671 }
1672
1673 static unsigned long cbq_get(struct Qdisc *sch, u32 classid)
1674 {
1675         struct cbq_sched_data *q = qdisc_priv(sch);
1676         struct cbq_class *cl = cbq_class_lookup(q, classid);
1677
1678         if (cl) {
1679                 cl->refcnt++;
1680                 return (unsigned long)cl;
1681         }
1682         return 0;
1683 }
1684
1685 static void cbq_destroy_class(struct Qdisc *sch, struct cbq_class *cl)
1686 {
1687         struct cbq_sched_data *q = qdisc_priv(sch);
1688
1689         WARN_ON(cl->filters);
1690
1691         tcf_destroy_chain(&cl->filter_list);
1692         qdisc_destroy(cl->q);
1693         qdisc_put_rtab(cl->R_tab);
1694         gen_kill_estimator(&cl->bstats, &cl->rate_est);
1695         if (cl != &q->link)
1696                 kfree(cl);
1697 }
1698
1699 static void cbq_destroy(struct Qdisc *sch)
1700 {
1701         struct cbq_sched_data *q = qdisc_priv(sch);
1702         struct hlist_node *next;
1703         struct cbq_class *cl;
1704         unsigned int h;
1705
1706 #ifdef CONFIG_NET_CLS_ACT
1707         q->rx_class = NULL;
1708 #endif
1709         /*
1710          * Filters must be destroyed first because we don't destroy the
1711          * classes from root to leafs which means that filters can still
1712          * be bound to classes which have been destroyed already. --TGR '04
1713          */
1714         for (h = 0; h < q->clhash.hashsize; h++) {
1715                 hlist_for_each_entry(cl, &q->clhash.hash[h], common.hnode)
1716                         tcf_destroy_chain(&cl->filter_list);
1717         }
1718         for (h = 0; h < q->clhash.hashsize; h++) {
1719                 hlist_for_each_entry_safe(cl, next, &q->clhash.hash[h],
1720                                           common.hnode)
1721                         cbq_destroy_class(sch, cl);
1722         }
1723         qdisc_class_hash_destroy(&q->clhash);
1724 }
1725
1726 static void cbq_put(struct Qdisc *sch, unsigned long arg)
1727 {
1728         struct cbq_class *cl = (struct cbq_class *)arg;
1729
1730         if (--cl->refcnt == 0) {
1731 #ifdef CONFIG_NET_CLS_ACT
1732                 spinlock_t *root_lock = qdisc_root_sleeping_lock(sch);
1733                 struct cbq_sched_data *q = qdisc_priv(sch);
1734
1735                 spin_lock_bh(root_lock);
1736                 if (q->rx_class == cl)
1737                         q->rx_class = NULL;
1738                 spin_unlock_bh(root_lock);
1739 #endif
1740
1741                 cbq_destroy_class(sch, cl);
1742         }
1743 }
1744
1745 static int
1746 cbq_change_class(struct Qdisc *sch, u32 classid, u32 parentid, struct nlattr **tca,
1747                  unsigned long *arg)
1748 {
1749         int err;
1750         struct cbq_sched_data *q = qdisc_priv(sch);
1751         struct cbq_class *cl = (struct cbq_class *)*arg;
1752         struct nlattr *opt = tca[TCA_OPTIONS];
1753         struct nlattr *tb[TCA_CBQ_MAX + 1];
1754         struct cbq_class *parent;
1755         struct qdisc_rate_table *rtab = NULL;
1756
1757         if (opt == NULL)
1758                 return -EINVAL;
1759
1760         err = nla_parse_nested(tb, TCA_CBQ_MAX, opt, cbq_policy);
1761         if (err < 0)
1762                 return err;
1763
1764         if (cl) {
1765                 /* Check parent */
1766                 if (parentid) {
1767                         if (cl->tparent &&
1768                             cl->tparent->common.classid != parentid)
1769                                 return -EINVAL;
1770                         if (!cl->tparent && parentid != TC_H_ROOT)
1771                                 return -EINVAL;
1772                 }
1773
1774                 if (tb[TCA_CBQ_RATE]) {
1775                         rtab = qdisc_get_rtab(nla_data(tb[TCA_CBQ_RATE]),
1776                                               tb[TCA_CBQ_RTAB]);
1777                         if (rtab == NULL)
1778                                 return -EINVAL;
1779                 }
1780
1781                 if (tca[TCA_RATE]) {
1782                         err = gen_replace_estimator(&cl->bstats, &cl->rate_est,
1783                                                     qdisc_root_sleeping_lock(sch),
1784                                                     tca[TCA_RATE]);
1785                         if (err) {
1786                                 if (rtab)
1787                                         qdisc_put_rtab(rtab);
1788                                 return err;
1789                         }
1790                 }
1791
1792                 /* Change class parameters */
1793                 sch_tree_lock(sch);
1794
1795                 if (cl->next_alive != NULL)
1796                         cbq_deactivate_class(cl);
1797
1798                 if (rtab) {
1799                         qdisc_put_rtab(cl->R_tab);
1800                         cl->R_tab = rtab;
1801                 }
1802
1803                 if (tb[TCA_CBQ_LSSOPT])
1804                         cbq_set_lss(cl, nla_data(tb[TCA_CBQ_LSSOPT]));
1805
1806                 if (tb[TCA_CBQ_WRROPT]) {
1807                         cbq_rmprio(q, cl);
1808                         cbq_set_wrr(cl, nla_data(tb[TCA_CBQ_WRROPT]));
1809                 }
1810
1811                 if (tb[TCA_CBQ_OVL_STRATEGY])
1812                         cbq_set_overlimit(cl, nla_data(tb[TCA_CBQ_OVL_STRATEGY]));
1813
1814 #ifdef CONFIG_NET_CLS_ACT
1815                 if (tb[TCA_CBQ_POLICE])
1816                         cbq_set_police(cl, nla_data(tb[TCA_CBQ_POLICE]));
1817 #endif
1818
1819                 if (tb[TCA_CBQ_FOPT])
1820                         cbq_set_fopt(cl, nla_data(tb[TCA_CBQ_FOPT]));
1821
1822                 if (cl->q->q.qlen)
1823                         cbq_activate_class(cl);
1824
1825                 sch_tree_unlock(sch);
1826
1827                 return 0;
1828         }
1829
1830         if (parentid == TC_H_ROOT)
1831                 return -EINVAL;
1832
1833         if (tb[TCA_CBQ_WRROPT] == NULL || tb[TCA_CBQ_RATE] == NULL ||
1834             tb[TCA_CBQ_LSSOPT] == NULL)
1835                 return -EINVAL;
1836
1837         rtab = qdisc_get_rtab(nla_data(tb[TCA_CBQ_RATE]), tb[TCA_CBQ_RTAB]);
1838         if (rtab == NULL)
1839                 return -EINVAL;
1840
1841         if (classid) {
1842                 err = -EINVAL;
1843                 if (TC_H_MAJ(classid ^ sch->handle) ||
1844                     cbq_class_lookup(q, classid))
1845                         goto failure;
1846         } else {
1847                 int i;
1848                 classid = TC_H_MAKE(sch->handle, 0x8000);
1849
1850                 for (i = 0; i < 0x8000; i++) {
1851                         if (++q->hgenerator >= 0x8000)
1852                                 q->hgenerator = 1;
1853                         if (cbq_class_lookup(q, classid|q->hgenerator) == NULL)
1854                                 break;
1855                 }
1856                 err = -ENOSR;
1857                 if (i >= 0x8000)
1858                         goto failure;
1859                 classid = classid|q->hgenerator;
1860         }
1861
1862         parent = &q->link;
1863         if (parentid) {
1864                 parent = cbq_class_lookup(q, parentid);
1865                 err = -EINVAL;
1866                 if (parent == NULL)
1867                         goto failure;
1868         }
1869
1870         err = -ENOBUFS;
1871         cl = kzalloc(sizeof(*cl), GFP_KERNEL);
1872         if (cl == NULL)
1873                 goto failure;
1874
1875         if (tca[TCA_RATE]) {
1876                 err = gen_new_estimator(&cl->bstats, &cl->rate_est,
1877                                         qdisc_root_sleeping_lock(sch),
1878                                         tca[TCA_RATE]);
1879                 if (err) {
1880                         kfree(cl);
1881                         goto failure;
1882                 }
1883         }
1884
1885         cl->R_tab = rtab;
1886         rtab = NULL;
1887         cl->refcnt = 1;
1888         cl->q = qdisc_create_dflt(sch->dev_queue, &pfifo_qdisc_ops, classid);
1889         if (!cl->q)
1890                 cl->q = &noop_qdisc;
1891         cl->common.classid = classid;
1892         cl->tparent = parent;
1893         cl->qdisc = sch;
1894         cl->allot = parent->allot;
1895         cl->quantum = cl->allot;
1896         cl->weight = cl->R_tab->rate.rate;
1897
1898         sch_tree_lock(sch);
1899         cbq_link_class(cl);
1900         cl->borrow = cl->tparent;
1901         if (cl->tparent != &q->link)
1902                 cl->share = cl->tparent;
1903         cbq_adjust_levels(parent);
1904         cl->minidle = -0x7FFFFFFF;
1905         cbq_set_lss(cl, nla_data(tb[TCA_CBQ_LSSOPT]));
1906         cbq_set_wrr(cl, nla_data(tb[TCA_CBQ_WRROPT]));
1907         if (cl->ewma_log == 0)
1908                 cl->ewma_log = q->link.ewma_log;
1909         if (cl->maxidle == 0)
1910                 cl->maxidle = q->link.maxidle;
1911         if (cl->avpkt == 0)
1912                 cl->avpkt = q->link.avpkt;
1913         cl->overlimit = cbq_ovl_classic;
1914         if (tb[TCA_CBQ_OVL_STRATEGY])
1915                 cbq_set_overlimit(cl, nla_data(tb[TCA_CBQ_OVL_STRATEGY]));
1916 #ifdef CONFIG_NET_CLS_ACT
1917         if (tb[TCA_CBQ_POLICE])
1918                 cbq_set_police(cl, nla_data(tb[TCA_CBQ_POLICE]));
1919 #endif
1920         if (tb[TCA_CBQ_FOPT])
1921                 cbq_set_fopt(cl, nla_data(tb[TCA_CBQ_FOPT]));
1922         sch_tree_unlock(sch);
1923
1924         qdisc_class_hash_grow(sch, &q->clhash);
1925
1926         *arg = (unsigned long)cl;
1927         return 0;
1928
1929 failure:
1930         qdisc_put_rtab(rtab);
1931         return err;
1932 }
1933
1934 static int cbq_delete(struct Qdisc *sch, unsigned long arg)
1935 {
1936         struct cbq_sched_data *q = qdisc_priv(sch);
1937         struct cbq_class *cl = (struct cbq_class *)arg;
1938         unsigned int qlen;
1939
1940         if (cl->filters || cl->children || cl == &q->link)
1941                 return -EBUSY;
1942
1943         sch_tree_lock(sch);
1944
1945         qlen = cl->q->q.qlen;
1946         qdisc_reset(cl->q);
1947         qdisc_tree_decrease_qlen(cl->q, qlen);
1948
1949         if (cl->next_alive)
1950                 cbq_deactivate_class(cl);
1951
1952         if (q->tx_borrowed == cl)
1953                 q->tx_borrowed = q->tx_class;
1954         if (q->tx_class == cl) {
1955                 q->tx_class = NULL;
1956                 q->tx_borrowed = NULL;
1957         }
1958 #ifdef CONFIG_NET_CLS_ACT
1959         if (q->rx_class == cl)
1960                 q->rx_class = NULL;
1961 #endif
1962
1963         cbq_unlink_class(cl);
1964         cbq_adjust_levels(cl->tparent);
1965         cl->defmap = 0;
1966         cbq_sync_defmap(cl);
1967
1968         cbq_rmprio(q, cl);
1969         sch_tree_unlock(sch);
1970
1971         BUG_ON(--cl->refcnt == 0);
1972         /*
1973          * This shouldn't happen: we "hold" one cops->get() when called
1974          * from tc_ctl_tclass; the destroy method is done from cops->put().
1975          */
1976
1977         return 0;
1978 }
1979
1980 static struct tcf_proto **cbq_find_tcf(struct Qdisc *sch, unsigned long arg)
1981 {
1982         struct cbq_sched_data *q = qdisc_priv(sch);
1983         struct cbq_class *cl = (struct cbq_class *)arg;
1984
1985         if (cl == NULL)
1986                 cl = &q->link;
1987
1988         return &cl->filter_list;
1989 }
1990
1991 static unsigned long cbq_bind_filter(struct Qdisc *sch, unsigned long parent,
1992                                      u32 classid)
1993 {
1994         struct cbq_sched_data *q = qdisc_priv(sch);
1995         struct cbq_class *p = (struct cbq_class *)parent;
1996         struct cbq_class *cl = cbq_class_lookup(q, classid);
1997
1998         if (cl) {
1999                 if (p && p->level <= cl->level)
2000                         return 0;
2001                 cl->filters++;
2002                 return (unsigned long)cl;
2003         }
2004         return 0;
2005 }
2006
2007 static void cbq_unbind_filter(struct Qdisc *sch, unsigned long arg)
2008 {
2009         struct cbq_class *cl = (struct cbq_class *)arg;
2010
2011         cl->filters--;
2012 }
2013
2014 static void cbq_walk(struct Qdisc *sch, struct qdisc_walker *arg)
2015 {
2016         struct cbq_sched_data *q = qdisc_priv(sch);
2017         struct cbq_class *cl;
2018         unsigned int h;
2019
2020         if (arg->stop)
2021                 return;
2022
2023         for (h = 0; h < q->clhash.hashsize; h++) {
2024                 hlist_for_each_entry(cl, &q->clhash.hash[h], common.hnode) {
2025                         if (arg->count < arg->skip) {
2026                                 arg->count++;
2027                                 continue;
2028                         }
2029                         if (arg->fn(sch, (unsigned long)cl, arg) < 0) {
2030                                 arg->stop = 1;
2031                                 return;
2032                         }
2033                         arg->count++;
2034                 }
2035         }
2036 }
2037
2038 static const struct Qdisc_class_ops cbq_class_ops = {
2039         .graft          =       cbq_graft,
2040         .leaf           =       cbq_leaf,
2041         .qlen_notify    =       cbq_qlen_notify,
2042         .get            =       cbq_get,
2043         .put            =       cbq_put,
2044         .change         =       cbq_change_class,
2045         .delete         =       cbq_delete,
2046         .walk           =       cbq_walk,
2047         .tcf_chain      =       cbq_find_tcf,
2048         .bind_tcf       =       cbq_bind_filter,
2049         .unbind_tcf     =       cbq_unbind_filter,
2050         .dump           =       cbq_dump_class,
2051         .dump_stats     =       cbq_dump_class_stats,
2052 };
2053
2054 static struct Qdisc_ops cbq_qdisc_ops __read_mostly = {
2055         .next           =       NULL,
2056         .cl_ops         =       &cbq_class_ops,
2057         .id             =       "cbq",
2058         .priv_size      =       sizeof(struct cbq_sched_data),
2059         .enqueue        =       cbq_enqueue,
2060         .dequeue        =       cbq_dequeue,
2061         .peek           =       qdisc_peek_dequeued,
2062         .drop           =       cbq_drop,
2063         .init           =       cbq_init,
2064         .reset          =       cbq_reset,
2065         .destroy        =       cbq_destroy,
2066         .change         =       NULL,
2067         .dump           =       cbq_dump,
2068         .dump_stats     =       cbq_dump_stats,
2069         .owner          =       THIS_MODULE,
2070 };
2071
2072 static int __init cbq_module_init(void)
2073 {
2074         return register_qdisc(&cbq_qdisc_ops);
2075 }
2076 static void __exit cbq_module_exit(void)
2077 {
2078         unregister_qdisc(&cbq_qdisc_ops);
2079 }
2080 module_init(cbq_module_init)
2081 module_exit(cbq_module_exit)
2082 MODULE_LICENSE("GPL");