net/sched/cls_tcindex.c

   1 /*
   2  * net/sched/cls_tcindex.c      Packet classifier for skb->tc_index
   3  *
   4  * Written 1998,1999 by Werner Almesberger, EPFL ICA
   5  */
   6
   7 #include <linux/module.h>
   8 #include <linux/types.h>
   9 #include <linux/kernel.h>
  10 #include <linux/skbuff.h>
  11 #include <linux/errno.h>
  12 #include <linux/slab.h>
  13 #include <net/act_api.h>
  14 #include <net/netlink.h>
  15 #include <net/pkt_cls.h>
  16 #include <net/sch_generic.h>
  17
  18 /*
  19  * Passing parameters to the root seems to be done more awkwardly than really
  20  * necessary. At least, u32 doesn't seem to use such dirty hacks. To be
  21  * verified. FIXME.
  22  */
  23
  24 #define PERFECT_HASH_THRESHOLD  64      /* use perfect hash if not bigger */
  25 #define DEFAULT_HASH_SIZE       64      /* optimized for diffserv */
  26
  27
  28 struct tcindex_filter_result {
  29         struct tcf_exts         exts;
  30         struct tcf_result       res;
  31         union {
  32                 struct work_struct      work;
  33                 struct rcu_head         rcu;
  34         };
  35 };
  36
  37 struct tcindex_filter {
  38         u16 key;
  39         struct tcindex_filter_result result;
  40         struct tcindex_filter __rcu *next;
  41         union {
  42                 struct work_struct work;
  43                 struct rcu_head rcu;
  44         };
  45 };
  46
  47
  48 struct tcindex_data {
  49         struct tcindex_filter_result *perfect; /* perfect hash; NULL if none */
  50         struct tcindex_filter __rcu **h; /* imperfect hash; */
  51         struct tcf_proto *tp;
  52         u16 mask;               /* AND key with mask */
  53         u32 shift;              /* shift ANDed key to the right */
  54         u32 hash;               /* hash table size; 0 if undefined */
  55         u32 alloc_hash;         /* allocated size */
  56         u32 fall_through;       /* 0: only classify if explicit match */
  57         struct rcu_head rcu;
  58 };
  59
  60 static inline int tcindex_filter_is_set(struct tcindex_filter_result *r)
  61 {
  62         return tcf_exts_has_actions(&r->exts) || r->res.classid;
  63 }
  64
  65 static struct tcindex_filter_result *tcindex_lookup(struct tcindex_data *p,
  66                                                     u16 key)
  67 {
  68         if (p->perfect) {
  69                 struct tcindex_filter_result *f = p->perfect + key;
  70
  71                 return tcindex_filter_is_set(f) ? f : NULL;
  72         } else if (p->h) {
  73                 struct tcindex_filter __rcu **fp;
  74                 struct tcindex_filter *f;
  75
  76                 fp = &p->h[key % p->hash];
  77                 for (f = rcu_dereference_bh_rtnl(*fp);
  78                      f;
  79                      fp = &f->next, f = rcu_dereference_bh_rtnl(*fp))
  80                         if (f->key == key)
  81                                 return &f->result;
  82         }
  83
  84         return NULL;
  85 }
  86
  87
  88 static int tcindex_classify(struct sk_buff *skb, const struct tcf_proto *tp,
  89                             struct tcf_result *res)
  90 {
  91         struct tcindex_data *p = rcu_dereference_bh(tp->root);
  92         struct tcindex_filter_result *f;
  93         int key = (skb->tc_index & p->mask) >> p->shift;
  94
  95         pr_debug("tcindex_classify(skb %p,tp %p,res %p),p %p\n",
  96                  skb, tp, res, p);
  97
  98         f = tcindex_lookup(p, key);
  99         if (!f) {
 100                 struct Qdisc *q = tcf_block_q(tp->chain->block);
 101
 102                 if (!p->fall_through)
 103                         return -1;
 104                 res->classid = TC_H_MAKE(TC_H_MAJ(q->handle), key);
 105                 res->class = 0;
 106                 pr_debug("alg 0x%x\n", res->classid);
 107                 return 0;
 108         }
 109         *res = f->res;
 110         pr_debug("map 0x%x\n", res->classid);
 111
 112         return tcf_exts_exec(skb, &f->exts, res);
 113 }
 114
 115
 116 static void *tcindex_get(struct tcf_proto *tp, u32 handle)
 117 {
 118         struct tcindex_data *p = rtnl_dereference(tp->root);
 119         struct tcindex_filter_result *r;
 120
 121         pr_debug("tcindex_get(tp %p,handle 0x%08x)\n", tp, handle);
 122         if (p->perfect && handle >= p->alloc_hash)
 123                 return NULL;
 124         r = tcindex_lookup(p, handle);
 125         return r && tcindex_filter_is_set(r) ? r : NULL;
 126 }
 127
 128 static int tcindex_init(struct tcf_proto *tp)
 129 {
 130         struct tcindex_data *p;
 131
 132         pr_debug("tcindex_init(tp %p)\n", tp);
 133         p = kzalloc(sizeof(struct tcindex_data), GFP_KERNEL);
 134         if (!p)
 135                 return -ENOMEM;
 136
 137         p->mask = 0xffff;
 138         p->hash = DEFAULT_HASH_SIZE;
 139         p->fall_through = 1;
 140
 141         rcu_assign_pointer(tp->root, p);
 142         return 0;
 143 }
 144
 145 static void __tcindex_destroy_rexts(struct tcindex_filter_result *r)
 146 {
 147         tcf_exts_destroy(&r->exts);
 148         tcf_exts_put_net(&r->exts);
 149 }
 150
 151 static void tcindex_destroy_rexts_work(struct work_struct *work)
 152 {
 153         struct tcindex_filter_result *r;
 154
 155         r = container_of(work, struct tcindex_filter_result, work);
 156         rtnl_lock();
 157         __tcindex_destroy_rexts(r);
 158         rtnl_unlock();
 159 }
 160
 161 static void tcindex_destroy_rexts(struct rcu_head *head)
 162 {
 163         struct tcindex_filter_result *r;
 164
 165         r = container_of(head, struct tcindex_filter_result, rcu);
 166         INIT_WORK(&r->work, tcindex_destroy_rexts_work);
 167         tcf_queue_work(&r->work);
 168 }
 169
 170 static void __tcindex_destroy_fexts(struct tcindex_filter *f)
 171 {
 172         tcf_exts_destroy(&f->result.exts);
 173         tcf_exts_put_net(&f->result.exts);
 174         kfree(f);
 175 }
 176
 177 static void tcindex_destroy_fexts_work(struct work_struct *work)
 178 {
 179         struct tcindex_filter *f = container_of(work, struct tcindex_filter,
 180                                                 work);
 181
 182         rtnl_lock();
 183         __tcindex_destroy_fexts(f);
 184         rtnl_unlock();
 185 }
 186
 187 static void tcindex_destroy_fexts(struct rcu_head *head)
 188 {
 189         struct tcindex_filter *f = container_of(head, struct tcindex_filter,
 190                                                 rcu);
 191
 192         INIT_WORK(&f->work, tcindex_destroy_fexts_work);
 193         tcf_queue_work(&f->work);
 194 }
 195
 196 static int tcindex_delete(struct tcf_proto *tp, void *arg, bool *last,
 197                           struct netlink_ext_ack *extack)
 198 {
 199         struct tcindex_data *p = rtnl_dereference(tp->root);
 200         struct tcindex_filter_result *r = arg;
 201         struct tcindex_filter __rcu **walk;
 202         struct tcindex_filter *f = NULL;
 203
 204         pr_debug("tcindex_delete(tp %p,arg %p),p %p\n", tp, arg, p);
 205         if (p->perfect) {
 206                 if (!r->res.class)
 207                         return -ENOENT;
 208         } else {
 209                 int i;
 210
 211                 for (i = 0; i < p->hash; i++) {
 212                         walk = p->h + i;
 213                         for (f = rtnl_dereference(*walk); f;
 214                              walk = &f->next, f = rtnl_dereference(*walk)) {
 215                                 if (&f->result == r)
 216                                         goto found;
 217                         }
 218                 }
 219                 return -ENOENT;
 220
 221 found:
 222                 rcu_assign_pointer(*walk, rtnl_dereference(f->next));
 223         }
 224         tcf_unbind_filter(tp, &r->res);
 225         /* all classifiers are required to call tcf_exts_destroy() after rcu
 226          * grace period, since converted-to-rcu actions are relying on that
 227          * in cleanup() callback
 228          */
 229         if (f) {
 230                 if (tcf_exts_get_net(&f->result.exts))
 231                         call_rcu(&f->rcu, tcindex_destroy_fexts);
 232                 else
 233                         __tcindex_destroy_fexts(f);
 234         } else {
 235                 if (tcf_exts_get_net(&r->exts))
 236                         call_rcu(&r->rcu, tcindex_destroy_rexts);
 237                 else
 238                         __tcindex_destroy_rexts(r);
 239         }
 240
 241         *last = false;
 242         return 0;
 243 }
 244
 245 static int tcindex_destroy_element(struct tcf_proto *tp,
 246                                    void *arg, struct tcf_walker *walker)
 247 {
 248         bool last;
 249
 250         return tcindex_delete(tp, arg, &last, NULL);
 251 }
 252
 253 static void __tcindex_destroy(struct rcu_head *head)
 254 {
 255         struct tcindex_data *p = container_of(head, struct tcindex_data, rcu);
 256
 257         kfree(p->perfect);
 258         kfree(p->h);
 259         kfree(p);
 260 }
 261
 262 static inline int
 263 valid_perfect_hash(struct tcindex_data *p)
 264 {
 265         return  p->hash > (p->mask >> p->shift);
 266 }
 267
 268 static const struct nla_policy tcindex_policy[TCA_TCINDEX_MAX + 1] = {
 269         [TCA_TCINDEX_HASH]              = { .type = NLA_U32 },
 270         [TCA_TCINDEX_MASK]              = { .type = NLA_U16 },
 271         [TCA_TCINDEX_SHIFT]             = { .type = NLA_U32 },
 272         [TCA_TCINDEX_FALL_THROUGH]      = { .type = NLA_U32 },
 273         [TCA_TCINDEX_CLASSID]           = { .type = NLA_U32 },
 274 };
 275
 276 static int tcindex_filter_result_init(struct tcindex_filter_result *r)
 277 {
 278         memset(r, 0, sizeof(*r));
 279         return tcf_exts_init(&r->exts, TCA_TCINDEX_ACT, TCA_TCINDEX_POLICE);
 280 }
 281
 282 static void __tcindex_partial_destroy(struct rcu_head *head)
 283 {
 284         struct tcindex_data *p = container_of(head, struct tcindex_data, rcu);
 285
 286         kfree(p->perfect);
 287         kfree(p);
 288 }
 289
 290 static void tcindex_free_perfect_hash(struct tcindex_data *cp)
 291 {
 292         int i;
 293
 294         for (i = 0; i < cp->hash; i++)
 295                 tcf_exts_destroy(&cp->perfect[i].exts);
 296         kfree(cp->perfect);
 297 }
 298
 299 static int tcindex_alloc_perfect_hash(struct tcindex_data *cp)
 300 {
 301         int i, err = 0;
 302
 303         cp->perfect = kcalloc(cp->hash, sizeof(struct tcindex_filter_result),
 304                               GFP_KERNEL);
 305         if (!cp->perfect)
 306                 return -ENOMEM;
 307
 308         for (i = 0; i < cp->hash; i++) {
 309                 err = tcf_exts_init(&cp->perfect[i].exts,
 310                                     TCA_TCINDEX_ACT, TCA_TCINDEX_POLICE);
 311                 if (err < 0)
 312                         goto errout;
 313         }
 314
 315         return 0;
 316
 317 errout:
 318         tcindex_free_perfect_hash(cp);
 319         return err;
 320 }
 321
 322 static int
 323 tcindex_set_parms(struct net *net, struct tcf_proto *tp, unsigned long base,
 324                   u32 handle, struct tcindex_data *p,
 325                   struct tcindex_filter_result *r, struct nlattr **tb,
 326                   struct nlattr *est, bool ovr, struct netlink_ext_ack *extack)
 327 {
 328         struct tcindex_filter_result new_filter_result, *old_r = r;
 329         struct tcindex_filter_result cr;
 330         struct tcindex_data *cp = NULL, *oldp;
 331         struct tcindex_filter *f = NULL; /* make gcc behave */
 332         int err, balloc = 0;
 333         struct tcf_exts e;
 334
 335         err = tcf_exts_init(&e, TCA_TCINDEX_ACT, TCA_TCINDEX_POLICE);
 336         if (err < 0)
 337                 return err;
 338         err = tcf_exts_validate(net, tp, tb, est, &e, ovr, extack);
 339         if (err < 0)
 340                 goto errout;
 341
 342         err = -ENOMEM;
 343         /* tcindex_data attributes must look atomic to classifier/lookup so
 344          * allocate new tcindex data and RCU assign it onto root. Keeping
 345          * perfect hash and hash pointers from old data.
 346          */
 347         cp = kzalloc(sizeof(*cp), GFP_KERNEL);
 348         if (!cp)
 349                 goto errout;
 350
 351         cp->mask = p->mask;
 352         cp->shift = p->shift;
 353         cp->hash = p->hash;
 354         cp->alloc_hash = p->alloc_hash;
 355         cp->fall_through = p->fall_through;
 356         cp->tp = tp;
 357
 358         if (p->perfect) {
 359                 int i;
 360
 361                 if (tcindex_alloc_perfect_hash(cp) < 0)
 362                         goto errout;
 363                 for (i = 0; i < cp->hash; i++)
 364                         cp->perfect[i].res = p->perfect[i].res;
 365                 balloc = 1;
 366         }
 367         cp->h = p->h;
 368
 369         err = tcindex_filter_result_init(&new_filter_result);
 370         if (err < 0)
 371                 goto errout1;
 372         err = tcindex_filter_result_init(&cr);
 373         if (err < 0)
 374                 goto errout1;
 375         if (old_r)
 376                 cr.res = r->res;
 377
 378         if (tb[TCA_TCINDEX_HASH])
 379                 cp->hash = nla_get_u32(tb[TCA_TCINDEX_HASH]);
 380
 381         if (tb[TCA_TCINDEX_MASK])
 382                 cp->mask = nla_get_u16(tb[TCA_TCINDEX_MASK]);
 383
 384         if (tb[TCA_TCINDEX_SHIFT])
 385                 cp->shift = nla_get_u32(tb[TCA_TCINDEX_SHIFT]);
 386
 387         err = -EBUSY;
 388
 389         /* Hash already allocated, make sure that we still meet the
 390          * requirements for the allocated hash.
 391          */
 392         if (cp->perfect) {
 393                 if (!valid_perfect_hash(cp) ||
 394                     cp->hash > cp->alloc_hash)
 395                         goto errout_alloc;
 396         } else if (cp->h && cp->hash != cp->alloc_hash) {
 397                 goto errout_alloc;
 398         }
 399
 400         err = -EINVAL;
 401         if (tb[TCA_TCINDEX_FALL_THROUGH])
 402                 cp->fall_through = nla_get_u32(tb[TCA_TCINDEX_FALL_THROUGH]);
 403
 404         if (!cp->hash) {
 405                 /* Hash not specified, use perfect hash if the upper limit
 406                  * of the hashing index is below the threshold.
 407                  */
 408                 if ((cp->mask >> cp->shift) < PERFECT_HASH_THRESHOLD)
 409                         cp->hash = (cp->mask >> cp->shift) + 1;
 410                 else
 411                         cp->hash = DEFAULT_HASH_SIZE;
 412         }
 413
 414         if (!cp->perfect && !cp->h)
 415                 cp->alloc_hash = cp->hash;
 416
 417         /* Note: this could be as restrictive as if (handle & ~(mask >> shift))
 418          * but then, we'd fail handles that may become valid after some future
 419          * mask change. While this is extremely unlikely to ever matter,
 420          * the check below is safer (and also more backwards-compatible).
 421          */
 422         if (cp->perfect || valid_perfect_hash(cp))
 423                 if (handle >= cp->alloc_hash)
 424                         goto errout_alloc;
 425
 426
 427         err = -ENOMEM;
 428         if (!cp->perfect && !cp->h) {
 429                 if (valid_perfect_hash(cp)) {
 430                         if (tcindex_alloc_perfect_hash(cp) < 0)
 431                                 goto errout_alloc;
 432                         balloc = 1;
 433                 } else {
 434                         struct tcindex_filter __rcu **hash;
 435
 436                         hash = kcalloc(cp->hash,
 437                                        sizeof(struct tcindex_filter *),
 438                                        GFP_KERNEL);
 439
 440                         if (!hash)
 441                                 goto errout_alloc;
 442
 443                         cp->h = hash;
 444                         balloc = 2;
 445                 }
 446         }
 447
 448         if (cp->perfect)
 449                 r = cp->perfect + handle;
 450         else
 451                 r = tcindex_lookup(cp, handle) ? : &new_filter_result;
 452
 453         if (r == &new_filter_result) {
 454                 f = kzalloc(sizeof(*f), GFP_KERNEL);
 455                 if (!f)
 456                         goto errout_alloc;
 457                 f->key = handle;
 458                 f->next = NULL;
 459                 err = tcindex_filter_result_init(&f->result);
 460                 if (err < 0) {
 461                         kfree(f);
 462                         goto errout_alloc;
 463                 }
 464         }
 465
 466         if (tb[TCA_TCINDEX_CLASSID]) {
 467                 cr.res.classid = nla_get_u32(tb[TCA_TCINDEX_CLASSID]);
 468                 tcf_bind_filter(tp, &cr.res, base);
 469         }
 470
 471         if (old_r)
 472                 tcf_exts_change(&r->exts, &e);
 473         else
 474                 tcf_exts_change(&cr.exts, &e);
 475
 476         if (old_r && old_r != r) {
 477                 err = tcindex_filter_result_init(old_r);
 478                 if (err < 0) {
 479                         kfree(f);
 480                         goto errout_alloc;
 481                 }
 482         }
 483
 484         oldp = p;
 485         r->res = cr.res;
 486         rcu_assign_pointer(tp->root, cp);
 487
 488         if (r == &new_filter_result) {
 489                 struct tcindex_filter *nfp;
 490                 struct tcindex_filter __rcu **fp;
 491
 492                 tcf_exts_change(&f->result.exts, &r->exts);
 493
 494                 fp = cp->h + (handle % cp->hash);
 495                 for (nfp = rtnl_dereference(*fp);
 496                      nfp;
 497                      fp = &nfp->next, nfp = rtnl_dereference(*fp))
 498                                 ; /* nothing */
 499
 500                 rcu_assign_pointer(*fp, f);
 501         }
 502
 503         if (oldp)
 504                 call_rcu(&oldp->rcu, __tcindex_partial_destroy);
 505         return 0;
 506
 507 errout_alloc:
 508         if (balloc == 1)
 509                 tcindex_free_perfect_hash(cp);
 510         else if (balloc == 2)
 511                 kfree(cp->h);
 512 errout1:
 513         tcf_exts_destroy(&cr.exts);
 514         tcf_exts_destroy(&new_filter_result.exts);
 515 errout:
 516         kfree(cp);
 517         tcf_exts_destroy(&e);
 518         return err;
 519 }
 520
 521 static int
 522 tcindex_change(struct net *net, struct sk_buff *in_skb,
 523                struct tcf_proto *tp, unsigned long base, u32 handle,
 524                struct nlattr **tca, void **arg, bool ovr,
 525                struct netlink_ext_ack *extack)
 526 {
 527         struct nlattr *opt = tca[TCA_OPTIONS];
 528         struct nlattr *tb[TCA_TCINDEX_MAX + 1];
 529         struct tcindex_data *p = rtnl_dereference(tp->root);
 530         struct tcindex_filter_result *r = *arg;
 531         int err;
 532
 533         pr_debug("tcindex_change(tp %p,handle 0x%08x,tca %p,arg %p),opt %p,"
 534             "p %p,r %p,*arg %p\n",
 535             tp, handle, tca, arg, opt, p, r, arg ? *arg : NULL);
 536
 537         if (!opt)
 538                 return 0;
 539
 540         err = nla_parse_nested(tb, TCA_TCINDEX_MAX, opt, tcindex_policy, NULL);
 541         if (err < 0)
 542                 return err;
 543
 544         return tcindex_set_parms(net, tp, base, handle, p, r, tb,
 545                                  tca[TCA_RATE], ovr, extack);
 546 }
 547
 548 static void tcindex_walk(struct tcf_proto *tp, struct tcf_walker *walker)
 549 {
 550         struct tcindex_data *p = rtnl_dereference(tp->root);
 551         struct tcindex_filter *f, *next;
 552         int i;
 553
 554         pr_debug("tcindex_walk(tp %p,walker %p),p %p\n", tp, walker, p);
 555         if (p->perfect) {
 556                 for (i = 0; i < p->hash; i++) {
 557                         if (!p->perfect[i].res.class)
 558                                 continue;
 559                         if (walker->count >= walker->skip) {
 560                                 if (walker->fn(tp, p->perfect + i, walker) < 0) {
 561                                         walker->stop = 1;
 562                                         return;
 563                                 }
 564                         }
 565                         walker->count++;
 566                 }
 567         }
 568         if (!p->h)
 569                 return;
 570         for (i = 0; i < p->hash; i++) {
 571                 for (f = rtnl_dereference(p->h[i]); f; f = next) {
 572                         next = rtnl_dereference(f->next);
 573                         if (walker->count >= walker->skip) {
 574                                 if (walker->fn(tp, &f->result, walker) < 0) {
 575                                         walker->stop = 1;
 576                                         return;
 577                                 }
 578                         }
 579                         walker->count++;
 580                 }
 581         }
 582 }
 583
 584 static void tcindex_destroy(struct tcf_proto *tp,
 585                             struct netlink_ext_ack *extack)
 586 {
 587         struct tcindex_data *p = rtnl_dereference(tp->root);
 588         struct tcf_walker walker;
 589
 590         pr_debug("tcindex_destroy(tp %p),p %p\n", tp, p);
 591         walker.count = 0;
 592         walker.skip = 0;
 593         walker.fn = tcindex_destroy_element;
 594         tcindex_walk(tp, &walker);
 595
 596         call_rcu(&p->rcu, __tcindex_destroy);
 597 }
 598
 599
 600 static int tcindex_dump(struct net *net, struct tcf_proto *tp, void *fh,
 601                         struct sk_buff *skb, struct tcmsg *t)
 602 {
 603         struct tcindex_data *p = rtnl_dereference(tp->root);
 604         struct tcindex_filter_result *r = fh;
 605         struct nlattr *nest;
 606
 607         pr_debug("tcindex_dump(tp %p,fh %p,skb %p,t %p),p %p,r %p\n",
 608                  tp, fh, skb, t, p, r);
 609         pr_debug("p->perfect %p p->h %p\n", p->perfect, p->h);
 610
 611         nest = nla_nest_start(skb, TCA_OPTIONS);
 612         if (nest == NULL)
 613                 goto nla_put_failure;
 614
 615         if (!fh) {
 616                 t->tcm_handle = ~0; /* whatever ... */
 617                 if (nla_put_u32(skb, TCA_TCINDEX_HASH, p->hash) ||
 618                     nla_put_u16(skb, TCA_TCINDEX_MASK, p->mask) ||
 619                     nla_put_u32(skb, TCA_TCINDEX_SHIFT, p->shift) ||
 620                     nla_put_u32(skb, TCA_TCINDEX_FALL_THROUGH, p->fall_through))
 621                         goto nla_put_failure;
 622                 nla_nest_end(skb, nest);
 623         } else {
 624                 if (p->perfect) {
 625                         t->tcm_handle = r - p->perfect;
 626                 } else {
 627                         struct tcindex_filter *f;
 628                         struct tcindex_filter __rcu **fp;
 629                         int i;
 630
 631                         t->tcm_handle = 0;
 632                         for (i = 0; !t->tcm_handle && i < p->hash; i++) {
 633                                 fp = &p->h[i];
 634                                 for (f = rtnl_dereference(*fp);
 635                                      !t->tcm_handle && f;
 636                                      fp = &f->next, f = rtnl_dereference(*fp)) {
 637                                         if (&f->result == r)
 638                                                 t->tcm_handle = f->key;
 639                                 }
 640                         }
 641                 }
 642                 pr_debug("handle = %d\n", t->tcm_handle);
 643                 if (r->res.class &&
 644                     nla_put_u32(skb, TCA_TCINDEX_CLASSID, r->res.classid))
 645                         goto nla_put_failure;
 646
 647                 if (tcf_exts_dump(skb, &r->exts) < 0)
 648                         goto nla_put_failure;
 649                 nla_nest_end(skb, nest);
 650
 651                 if (tcf_exts_dump_stats(skb, &r->exts) < 0)
 652                         goto nla_put_failure;
 653         }
 654
 655         return skb->len;
 656
 657 nla_put_failure:
 658         nla_nest_cancel(skb, nest);
 659         return -1;
 660 }
 661
 662 static void tcindex_bind_class(void *fh, u32 classid, unsigned long cl)
 663 {
 664         struct tcindex_filter_result *r = fh;
 665
 666         if (r && r->res.classid == classid)
 667                 r->res.class = cl;
 668 }
 669
 670 static struct tcf_proto_ops cls_tcindex_ops __read_mostly = {
 671         .kind           =       "tcindex",
 672         .classify       =       tcindex_classify,
 673         .init           =       tcindex_init,
 674         .destroy        =       tcindex_destroy,
 675         .get            =       tcindex_get,
 676         .change         =       tcindex_change,
 677         .delete         =       tcindex_delete,
 678         .walk           =       tcindex_walk,
 679         .dump           =       tcindex_dump,
 680         .bind_class     =       tcindex_bind_class,
 681         .owner          =       THIS_MODULE,
 682 };
 683
 684 static int __init init_tcindex(void)
 685 {
 686         return register_tcf_proto_ops(&cls_tcindex_ops);
 687 }
 688
 689 static void __exit exit_tcindex(void)
 690 {
 691         unregister_tcf_proto_ops(&cls_tcindex_ops);
 692 }
 693
 694 module_init(init_tcindex)
 695 module_exit(exit_tcindex)
 696 MODULE_LICENSE("GPL");