net/sched/cls_u32.c

   1 /*
   2  * net/sched/cls_u32.c  Ugly (or Universal) 32bit key Packet Classifier.
   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  *      The filters are packed to hash tables of key nodes
  12  *      with a set of 32bit key/mask pairs at every node.
  13  *      Nodes reference next level hash tables etc.
  14  *
  15  *      This scheme is the best universal classifier I managed to
  16  *      invent; it is not super-fast, but it is not slow (provided you
  17  *      program it correctly), and general enough.  And its relative
  18  *      speed grows as the number of rules becomes larger.
  19  *
  20  *      It seems that it represents the best middle point between
  21  *      speed and manageability both by human and by machine.
  22  *
  23  *      It is especially useful for link sharing combined with QoS;
  24  *      pure RSVP doesn't need such a general approach and can use
  25  *      much simpler (and faster) schemes, sort of cls_rsvp.c.
  26  *
  27  *      JHS: We should remove the CONFIG_NET_CLS_IND from here
  28  *      eventually when the meta match extension is made available
  29  *
  30  *      nfmark match added by Catalin(ux aka Dino) BOIE <catab at umbrella.ro>
  31  */
  32
  33 #include <linux/module.h>
  34 #include <linux/slab.h>
  35 #include <linux/types.h>
  36 #include <linux/kernel.h>
  37 #include <linux/string.h>
  38 #include <linux/errno.h>
  39 #include <linux/rtnetlink.h>
  40 #include <linux/skbuff.h>
  41 #include <net/netlink.h>
  42 #include <net/act_api.h>
  43 #include <net/pkt_cls.h>
  44
  45 struct tc_u_knode {
  46         struct tc_u_knode       *next;
  47         u32                     handle;
  48         struct tc_u_hnode       *ht_up;
  49         struct tcf_exts         exts;
  50 #ifdef CONFIG_NET_CLS_IND
  51         char                     indev[IFNAMSIZ];
  52 #endif
  53         u8                      fshift;
  54         struct tcf_result       res;
  55         struct tc_u_hnode       *ht_down;
  56 #ifdef CONFIG_CLS_U32_PERF
  57         struct tc_u32_pcnt      *pf;
  58 #endif
  59 #ifdef CONFIG_CLS_U32_MARK
  60         struct tc_u32_mark      mark;
  61 #endif
  62         struct tc_u32_sel       sel;
  63 };
  64
  65 struct tc_u_hnode {
  66         struct tc_u_hnode       *next;
  67         u32                     handle;
  68         u32                     prio;
  69         struct tc_u_common      *tp_c;
  70         int                     refcnt;
  71         unsigned int            divisor;
  72         struct tc_u_knode       *ht[1];
  73 };
  74
  75 struct tc_u_common {
  76         struct tc_u_hnode       *hlist;
  77         struct Qdisc            *q;
  78         int                     refcnt;
  79         u32                     hgenerator;
  80 };
  81
  82 static const struct tcf_ext_map u32_ext_map = {
  83         .action = TCA_U32_ACT,
  84         .police = TCA_U32_POLICE
  85 };
  86
  87 static inline unsigned int u32_hash_fold(__be32 key,
  88                                          const struct tc_u32_sel *sel,
  89                                          u8 fshift)
  90 {
  91         unsigned int h = ntohl(key & sel->hmask) >> fshift;
  92
  93         return h;
  94 }
  95
  96 static int u32_classify(struct sk_buff *skb, const struct tcf_proto *tp, struct tcf_result *res)
  97 {
  98         struct {
  99                 struct tc_u_knode *knode;
 100                 unsigned int      off;
 101         } stack[TC_U32_MAXDEPTH];
 102
 103         struct tc_u_hnode *ht = (struct tc_u_hnode *)tp->root;
 104         unsigned int off = skb_network_offset(skb);
 105         struct tc_u_knode *n;
 106         int sdepth = 0;
 107         int off2 = 0;
 108         int sel = 0;
 109 #ifdef CONFIG_CLS_U32_PERF
 110         int j;
 111 #endif
 112         int i, r;
 113
 114 next_ht:
 115         n = ht->ht[sel];
 116
 117 next_knode:
 118         if (n) {
 119                 struct tc_u32_key *key = n->sel.keys;
 120
 121 #ifdef CONFIG_CLS_U32_PERF
 122                 n->pf->rcnt += 1;
 123                 j = 0;
 124 #endif
 125
 126 #ifdef CONFIG_CLS_U32_MARK
 127                 if ((skb->mark & n->mark.mask) != n->mark.val) {
 128                         n = n->next;
 129                         goto next_knode;
 130                 } else {
 131                         n->mark.success++;
 132                 }
 133 #endif
 134
 135                 for (i = n->sel.nkeys; i > 0; i--, key++) {
 136                         int toff = off + key->off + (off2 & key->offmask);
 137                         __be32 *data, hdata;
 138
 139                         if (skb_headroom(skb) + toff > INT_MAX)
 140                                 goto out;
 141
 142                         data = skb_header_pointer(skb, toff, 4, &hdata);
 143                         if (!data)
 144                                 goto out;
 145                         if ((*data ^ key->val) & key->mask) {
 146                                 n = n->next;
 147                                 goto next_knode;
 148                         }
 149 #ifdef CONFIG_CLS_U32_PERF
 150                         n->pf->kcnts[j] += 1;
 151                         j++;
 152 #endif
 153                 }
 154                 if (n->ht_down == NULL) {
 155 check_terminal:
 156                         if (n->sel.flags & TC_U32_TERMINAL) {
 157
 158                                 *res = n->res;
 159 #ifdef CONFIG_NET_CLS_IND
 160                                 if (!tcf_match_indev(skb, n->indev)) {
 161                                         n = n->next;
 162                                         goto next_knode;
 163                                 }
 164 #endif
 165 #ifdef CONFIG_CLS_U32_PERF
 166                                 n->pf->rhit += 1;
 167 #endif
 168                                 r = tcf_exts_exec(skb, &n->exts, res);
 169                                 if (r < 0) {
 170                                         n = n->next;
 171                                         goto next_knode;
 172                                 }
 173
 174                                 return r;
 175                         }
 176                         n = n->next;
 177                         goto next_knode;
 178                 }
 179
 180                 /* PUSH */
 181                 if (sdepth >= TC_U32_MAXDEPTH)
 182                         goto deadloop;
 183                 stack[sdepth].knode = n;
 184                 stack[sdepth].off = off;
 185                 sdepth++;
 186
 187                 ht = n->ht_down;
 188                 sel = 0;
 189                 if (ht->divisor) {
 190                         __be32 *data, hdata;
 191
 192                         data = skb_header_pointer(skb, off + n->sel.hoff, 4,
 193                                                   &hdata);
 194                         if (!data)
 195                                 goto out;
 196                         sel = ht->divisor & u32_hash_fold(*data, &n->sel,
 197                                                           n->fshift);
 198                 }
 199                 if (!(n->sel.flags & (TC_U32_VAROFFSET | TC_U32_OFFSET | TC_U32_EAT)))
 200                         goto next_ht;
 201
 202                 if (n->sel.flags & (TC_U32_OFFSET | TC_U32_VAROFFSET)) {
 203                         off2 = n->sel.off + 3;
 204                         if (n->sel.flags & TC_U32_VAROFFSET) {
 205                                 __be16 *data, hdata;
 206
 207                                 data = skb_header_pointer(skb,
 208                                                           off + n->sel.offoff,
 209                                                           2, &hdata);
 210                                 if (!data)
 211                                         goto out;
 212                                 off2 += ntohs(n->sel.offmask & *data) >>
 213                                         n->sel.offshift;
 214                         }
 215                         off2 &= ~3;
 216                 }
 217                 if (n->sel.flags & TC_U32_EAT) {
 218                         off += off2;
 219                         off2 = 0;
 220                 }
 221
 222                 if (off < skb->len)
 223                         goto next_ht;
 224         }
 225
 226         /* POP */
 227         if (sdepth--) {
 228                 n = stack[sdepth].knode;
 229                 ht = n->ht_up;
 230                 off = stack[sdepth].off;
 231                 goto check_terminal;
 232         }
 233 out:
 234         return -1;
 235
 236 deadloop:
 237         net_warn_ratelimited("cls_u32: dead loop\n");
 238         return -1;
 239 }
 240
 241 static struct tc_u_hnode *
 242 u32_lookup_ht(struct tc_u_common *tp_c, u32 handle)
 243 {
 244         struct tc_u_hnode *ht;
 245
 246         for (ht = tp_c->hlist; ht; ht = ht->next)
 247                 if (ht->handle == handle)
 248                         break;
 249
 250         return ht;
 251 }
 252
 253 static struct tc_u_knode *
 254 u32_lookup_key(struct tc_u_hnode *ht, u32 handle)
 255 {
 256         unsigned int sel;
 257         struct tc_u_knode *n = NULL;
 258
 259         sel = TC_U32_HASH(handle);
 260         if (sel > ht->divisor)
 261                 goto out;
 262
 263         for (n = ht->ht[sel]; n; n = n->next)
 264                 if (n->handle == handle)
 265                         break;
 266 out:
 267         return n;
 268 }
 269
 270
 271 static unsigned long u32_get(struct tcf_proto *tp, u32 handle)
 272 {
 273         struct tc_u_hnode *ht;
 274         struct tc_u_common *tp_c = tp->data;
 275
 276         if (TC_U32_HTID(handle) == TC_U32_ROOT)
 277                 ht = tp->root;
 278         else
 279                 ht = u32_lookup_ht(tp_c, TC_U32_HTID(handle));
 280
 281         if (!ht)
 282                 return 0;
 283
 284         if (TC_U32_KEY(handle) == 0)
 285                 return (unsigned long)ht;
 286
 287         return (unsigned long)u32_lookup_key(ht, handle);
 288 }
 289
 290 static void u32_put(struct tcf_proto *tp, unsigned long f)
 291 {
 292 }
 293
 294 static u32 gen_new_htid(struct tc_u_common *tp_c)
 295 {
 296         int i = 0x800;
 297
 298         do {
 299                 if (++tp_c->hgenerator == 0x7FF)
 300                         tp_c->hgenerator = 1;
 301         } while (--i > 0 && u32_lookup_ht(tp_c, (tp_c->hgenerator|0x800)<<20));
 302
 303         return i > 0 ? (tp_c->hgenerator|0x800)<<20 : 0;
 304 }
 305
 306 static int u32_init(struct tcf_proto *tp)
 307 {
 308         struct tc_u_hnode *root_ht;
 309         struct tc_u_common *tp_c;
 310
 311         tp_c = tp->q->u32_node;
 312
 313         root_ht = kzalloc(sizeof(*root_ht), GFP_KERNEL);
 314         if (root_ht == NULL)
 315                 return -ENOBUFS;
 316
 317         root_ht->divisor = 0;
 318         root_ht->refcnt++;
 319         root_ht->handle = tp_c ? gen_new_htid(tp_c) : 0x80000000;
 320         root_ht->prio = tp->prio;
 321
 322         if (tp_c == NULL) {
 323                 tp_c = kzalloc(sizeof(*tp_c), GFP_KERNEL);
 324                 if (tp_c == NULL) {
 325                         kfree(root_ht);
 326                         return -ENOBUFS;
 327                 }
 328                 tp_c->q = tp->q;
 329                 tp->q->u32_node = tp_c;
 330         }
 331
 332         tp_c->refcnt++;
 333         root_ht->next = tp_c->hlist;
 334         tp_c->hlist = root_ht;
 335         root_ht->tp_c = tp_c;
 336
 337         tp->root = root_ht;
 338         tp->data = tp_c;
 339         return 0;
 340 }
 341
 342 static int u32_destroy_key(struct tcf_proto *tp, struct tc_u_knode *n)
 343 {
 344         tcf_unbind_filter(tp, &n->res);
 345         tcf_exts_destroy(tp, &n->exts);
 346         if (n->ht_down)
 347                 n->ht_down->refcnt--;
 348 #ifdef CONFIG_CLS_U32_PERF
 349         kfree(n->pf);
 350 #endif
 351         kfree(n);
 352         return 0;
 353 }
 354
 355 static int u32_delete_key(struct tcf_proto *tp, struct tc_u_knode* key)
 356 {
 357         struct tc_u_knode **kp;
 358         struct tc_u_hnode *ht = key->ht_up;
 359
 360         if (ht) {
 361                 for (kp = &ht->ht[TC_U32_HASH(key->handle)]; *kp; kp = &(*kp)->next) {
 362                         if (*kp == key) {
 363                                 tcf_tree_lock(tp);
 364                                 *kp = key->next;
 365                                 tcf_tree_unlock(tp);
 366
 367                                 u32_destroy_key(tp, key);
 368                                 return 0;
 369                         }
 370                 }
 371         }
 372         WARN_ON(1);
 373         return 0;
 374 }
 375
 376 static void u32_clear_hnode(struct tcf_proto *tp, struct tc_u_hnode *ht)
 377 {
 378         struct tc_u_knode *n;
 379         unsigned int h;
 380
 381         for (h = 0; h <= ht->divisor; h++) {
 382                 while ((n = ht->ht[h]) != NULL) {
 383                         ht->ht[h] = n->next;
 384
 385                         u32_destroy_key(tp, n);
 386                 }
 387         }
 388 }
 389
 390 static int u32_destroy_hnode(struct tcf_proto *tp, struct tc_u_hnode *ht)
 391 {
 392         struct tc_u_common *tp_c = tp->data;
 393         struct tc_u_hnode **hn;
 394
 395         WARN_ON(ht->refcnt);
 396
 397         u32_clear_hnode(tp, ht);
 398
 399         for (hn = &tp_c->hlist; *hn; hn = &(*hn)->next) {
 400                 if (*hn == ht) {
 401                         *hn = ht->next;
 402                         kfree(ht);
 403                         return 0;
 404                 }
 405         }
 406
 407         WARN_ON(1);
 408         return -ENOENT;
 409 }
 410
 411 static void u32_destroy(struct tcf_proto *tp)
 412 {
 413         struct tc_u_common *tp_c = tp->data;
 414         struct tc_u_hnode *root_ht = tp->root;
 415
 416         WARN_ON(root_ht == NULL);
 417
 418         if (root_ht && --root_ht->refcnt == 0)
 419                 u32_destroy_hnode(tp, root_ht);
 420
 421         if (--tp_c->refcnt == 0) {
 422                 struct tc_u_hnode *ht;
 423
 424                 tp->q->u32_node = NULL;
 425
 426                 for (ht = tp_c->hlist; ht; ht = ht->next) {
 427                         ht->refcnt--;
 428                         u32_clear_hnode(tp, ht);
 429                 }
 430
 431                 while ((ht = tp_c->hlist) != NULL) {
 432                         tp_c->hlist = ht->next;
 433
 434                         WARN_ON(ht->refcnt != 0);
 435
 436                         kfree(ht);
 437                 }
 438
 439                 kfree(tp_c);
 440         }
 441
 442         tp->data = NULL;
 443 }
 444
 445 static int u32_delete(struct tcf_proto *tp, unsigned long arg)
 446 {
 447         struct tc_u_hnode *ht = (struct tc_u_hnode *)arg;
 448
 449         if (ht == NULL)
 450                 return 0;
 451
 452         if (TC_U32_KEY(ht->handle))
 453                 return u32_delete_key(tp, (struct tc_u_knode *)ht);
 454
 455         if (tp->root == ht)
 456                 return -EINVAL;
 457
 458         if (ht->refcnt == 1) {
 459                 ht->refcnt--;
 460                 u32_destroy_hnode(tp, ht);
 461         } else {
 462                 return -EBUSY;
 463         }
 464
 465         return 0;
 466 }
 467
 468 static u32 gen_new_kid(struct tc_u_hnode *ht, u32 handle)
 469 {
 470         struct tc_u_knode *n;
 471         unsigned int i = 0x7FF;
 472
 473         for (n = ht->ht[TC_U32_HASH(handle)]; n; n = n->next)
 474                 if (i < TC_U32_NODE(n->handle))
 475                         i = TC_U32_NODE(n->handle);
 476         i++;
 477
 478         return handle | (i > 0xFFF ? 0xFFF : i);
 479 }
 480
 481 static const struct nla_policy u32_policy[TCA_U32_MAX + 1] = {
 482         [TCA_U32_CLASSID]       = { .type = NLA_U32 },
 483         [TCA_U32_HASH]          = { .type = NLA_U32 },
 484         [TCA_U32_LINK]          = { .type = NLA_U32 },
 485         [TCA_U32_DIVISOR]       = { .type = NLA_U32 },
 486         [TCA_U32_SEL]           = { .len = sizeof(struct tc_u32_sel) },
 487         [TCA_U32_INDEV]         = { .type = NLA_STRING, .len = IFNAMSIZ },
 488         [TCA_U32_MARK]          = { .len = sizeof(struct tc_u32_mark) },
 489 };
 490
 491 static int u32_set_parms(struct net *net, struct tcf_proto *tp,
 492                          unsigned long base, struct tc_u_hnode *ht,
 493                          struct tc_u_knode *n, struct nlattr **tb,
 494                          struct nlattr *est)
 495 {
 496         int err;
 497         struct tcf_exts e;
 498
 499         err = tcf_exts_validate(net, tp, tb, est, &e, &u32_ext_map);
 500         if (err < 0)
 501                 return err;
 502
 503         err = -EINVAL;
 504         if (tb[TCA_U32_LINK]) {
 505                 u32 handle = nla_get_u32(tb[TCA_U32_LINK]);
 506                 struct tc_u_hnode *ht_down = NULL, *ht_old;
 507
 508                 if (TC_U32_KEY(handle))
 509                         goto errout;
 510
 511                 if (handle) {
 512                         ht_down = u32_lookup_ht(ht->tp_c, handle);
 513
 514                         if (ht_down == NULL)
 515                                 goto errout;
 516                         ht_down->refcnt++;
 517                 }
 518
 519                 tcf_tree_lock(tp);
 520                 ht_old = n->ht_down;
 521                 n->ht_down = ht_down;
 522                 tcf_tree_unlock(tp);
 523
 524                 if (ht_old)
 525                         ht_old->refcnt--;
 526         }
 527         if (tb[TCA_U32_CLASSID]) {
 528                 n->res.classid = nla_get_u32(tb[TCA_U32_CLASSID]);
 529                 tcf_bind_filter(tp, &n->res, base);
 530         }
 531
 532 #ifdef CONFIG_NET_CLS_IND
 533         if (tb[TCA_U32_INDEV]) {
 534                 err = tcf_change_indev(tp, n->indev, tb[TCA_U32_INDEV]);
 535                 if (err < 0)
 536                         goto errout;
 537         }
 538 #endif
 539         tcf_exts_change(tp, &n->exts, &e);
 540
 541         return 0;
 542 errout:
 543         tcf_exts_destroy(tp, &e);
 544         return err;
 545 }
 546
 547 static int u32_change(struct net *net, struct sk_buff *in_skb,
 548                       struct tcf_proto *tp, unsigned long base, u32 handle,
 549                       struct nlattr **tca,
 550                       unsigned long *arg)
 551 {
 552         struct tc_u_common *tp_c = tp->data;
 553         struct tc_u_hnode *ht;
 554         struct tc_u_knode *n;
 555         struct tc_u32_sel *s;
 556         struct nlattr *opt = tca[TCA_OPTIONS];
 557         struct nlattr *tb[TCA_U32_MAX + 1];
 558         u32 htid;
 559         int err;
 560
 561         if (opt == NULL)
 562                 return handle ? -EINVAL : 0;
 563
 564         err = nla_parse_nested(tb, TCA_U32_MAX, opt, u32_policy);
 565         if (err < 0)
 566                 return err;
 567
 568         n = (struct tc_u_knode *)*arg;
 569         if (n) {
 570                 if (TC_U32_KEY(n->handle) == 0)
 571                         return -EINVAL;
 572
 573                 return u32_set_parms(net, tp, base, n->ht_up, n, tb,
 574                                      tca[TCA_RATE]);
 575         }
 576
 577         if (tb[TCA_U32_DIVISOR]) {
 578                 unsigned int divisor = nla_get_u32(tb[TCA_U32_DIVISOR]);
 579
 580                 if (--divisor > 0x100)
 581                         return -EINVAL;
 582                 if (TC_U32_KEY(handle))
 583                         return -EINVAL;
 584                 if (handle == 0) {
 585                         handle = gen_new_htid(tp->data);
 586                         if (handle == 0)
 587                                 return -ENOMEM;
 588                 }
 589                 ht = kzalloc(sizeof(*ht) + divisor*sizeof(void *), GFP_KERNEL);
 590                 if (ht == NULL)
 591                         return -ENOBUFS;
 592                 ht->tp_c = tp_c;
 593                 ht->refcnt = 1;
 594                 ht->divisor = divisor;
 595                 ht->handle = handle;
 596                 ht->prio = tp->prio;
 597                 ht->next = tp_c->hlist;
 598                 tp_c->hlist = ht;
 599                 *arg = (unsigned long)ht;
 600                 return 0;
 601         }
 602
 603         if (tb[TCA_U32_HASH]) {
 604                 htid = nla_get_u32(tb[TCA_U32_HASH]);
 605                 if (TC_U32_HTID(htid) == TC_U32_ROOT) {
 606                         ht = tp->root;
 607                         htid = ht->handle;
 608                 } else {
 609                         ht = u32_lookup_ht(tp->data, TC_U32_HTID(htid));
 610                         if (ht == NULL)
 611                                 return -EINVAL;
 612                 }
 613         } else {
 614                 ht = tp->root;
 615                 htid = ht->handle;
 616         }
 617
 618         if (ht->divisor < TC_U32_HASH(htid))
 619                 return -EINVAL;
 620
 621         if (handle) {
 622                 if (TC_U32_HTID(handle) && TC_U32_HTID(handle^htid))
 623                         return -EINVAL;
 624                 handle = htid | TC_U32_NODE(handle);
 625         } else
 626                 handle = gen_new_kid(ht, htid);
 627
 628         if (tb[TCA_U32_SEL] == NULL)
 629                 return -EINVAL;
 630
 631         s = nla_data(tb[TCA_U32_SEL]);
 632
 633         n = kzalloc(sizeof(*n) + s->nkeys*sizeof(struct tc_u32_key), GFP_KERNEL);
 634         if (n == NULL)
 635                 return -ENOBUFS;
 636
 637 #ifdef CONFIG_CLS_U32_PERF
 638         n->pf = kzalloc(sizeof(struct tc_u32_pcnt) + s->nkeys*sizeof(u64), GFP_KERNEL);
 639         if (n->pf == NULL) {
 640                 kfree(n);
 641                 return -ENOBUFS;
 642         }
 643 #endif
 644
 645         memcpy(&n->sel, s, sizeof(*s) + s->nkeys*sizeof(struct tc_u32_key));
 646         n->ht_up = ht;
 647         n->handle = handle;
 648         n->fshift = s->hmask ? ffs(ntohl(s->hmask)) - 1 : 0;
 649
 650 #ifdef CONFIG_CLS_U32_MARK
 651         if (tb[TCA_U32_MARK]) {
 652                 struct tc_u32_mark *mark;
 653
 654                 mark = nla_data(tb[TCA_U32_MARK]);
 655                 memcpy(&n->mark, mark, sizeof(struct tc_u32_mark));
 656                 n->mark.success = 0;
 657         }
 658 #endif
 659
 660         err = u32_set_parms(net, tp, base, ht, n, tb, tca[TCA_RATE]);
 661         if (err == 0) {
 662                 struct tc_u_knode **ins;
 663                 for (ins = &ht->ht[TC_U32_HASH(handle)]; *ins; ins = &(*ins)->next)
 664                         if (TC_U32_NODE(handle) < TC_U32_NODE((*ins)->handle))
 665                                 break;
 666
 667                 n->next = *ins;
 668                 tcf_tree_lock(tp);
 669                 *ins = n;
 670                 tcf_tree_unlock(tp);
 671
 672                 *arg = (unsigned long)n;
 673                 return 0;
 674         }
 675 #ifdef CONFIG_CLS_U32_PERF
 676         kfree(n->pf);
 677 #endif
 678         kfree(n);
 679         return err;
 680 }
 681
 682 static void u32_walk(struct tcf_proto *tp, struct tcf_walker *arg)
 683 {
 684         struct tc_u_common *tp_c = tp->data;
 685         struct tc_u_hnode *ht;
 686         struct tc_u_knode *n;
 687         unsigned int h;
 688
 689         if (arg->stop)
 690                 return;
 691
 692         for (ht = tp_c->hlist; ht; ht = ht->next) {
 693                 if (ht->prio != tp->prio)
 694                         continue;
 695                 if (arg->count >= arg->skip) {
 696                         if (arg->fn(tp, (unsigned long)ht, arg) < 0) {
 697                                 arg->stop = 1;
 698                                 return;
 699                         }
 700                 }
 701                 arg->count++;
 702                 for (h = 0; h <= ht->divisor; h++) {
 703                         for (n = ht->ht[h]; n; n = n->next) {
 704                                 if (arg->count < arg->skip) {
 705                                         arg->count++;
 706                                         continue;
 707                                 }
 708                                 if (arg->fn(tp, (unsigned long)n, arg) < 0) {
 709                                         arg->stop = 1;
 710                                         return;
 711                                 }
 712                                 arg->count++;
 713                         }
 714                 }
 715         }
 716 }
 717
 718 static int u32_dump(struct tcf_proto *tp, unsigned long fh,
 719                      struct sk_buff *skb, struct tcmsg *t)
 720 {
 721         struct tc_u_knode *n = (struct tc_u_knode *)fh;
 722         struct nlattr *nest;
 723
 724         if (n == NULL)
 725                 return skb->len;
 726
 727         t->tcm_handle = n->handle;
 728
 729         nest = nla_nest_start(skb, TCA_OPTIONS);
 730         if (nest == NULL)
 731                 goto nla_put_failure;
 732
 733         if (TC_U32_KEY(n->handle) == 0) {
 734                 struct tc_u_hnode *ht = (struct tc_u_hnode *)fh;
 735                 u32 divisor = ht->divisor + 1;
 736
 737                 if (nla_put_u32(skb, TCA_U32_DIVISOR, divisor))
 738                         goto nla_put_failure;
 739         } else {
 740                 if (nla_put(skb, TCA_U32_SEL,
 741                             sizeof(n->sel) + n->sel.nkeys*sizeof(struct tc_u32_key),
 742                             &n->sel))
 743                         goto nla_put_failure;
 744                 if (n->ht_up) {
 745                         u32 htid = n->handle & 0xFFFFF000;
 746                         if (nla_put_u32(skb, TCA_U32_HASH, htid))
 747                                 goto nla_put_failure;
 748                 }
 749                 if (n->res.classid &&
 750                     nla_put_u32(skb, TCA_U32_CLASSID, n->res.classid))
 751                         goto nla_put_failure;
 752                 if (n->ht_down &&
 753                     nla_put_u32(skb, TCA_U32_LINK, n->ht_down->handle))
 754                         goto nla_put_failure;
 755
 756 #ifdef CONFIG_CLS_U32_MARK
 757                 if ((n->mark.val || n->mark.mask) &&
 758                     nla_put(skb, TCA_U32_MARK, sizeof(n->mark), &n->mark))
 759                         goto nla_put_failure;
 760 #endif
 761
 762                 if (tcf_exts_dump(skb, &n->exts, &u32_ext_map) < 0)
 763                         goto nla_put_failure;
 764
 765 #ifdef CONFIG_NET_CLS_IND
 766                 if (strlen(n->indev) &&
 767                     nla_put_string(skb, TCA_U32_INDEV, n->indev))
 768                         goto nla_put_failure;
 769 #endif
 770 #ifdef CONFIG_CLS_U32_PERF
 771                 if (nla_put(skb, TCA_U32_PCNT,
 772                             sizeof(struct tc_u32_pcnt) + n->sel.nkeys*sizeof(u64),
 773                             n->pf))
 774                         goto nla_put_failure;
 775 #endif
 776         }
 777
 778         nla_nest_end(skb, nest);
 779
 780         if (TC_U32_KEY(n->handle))
 781                 if (tcf_exts_dump_stats(skb, &n->exts, &u32_ext_map) < 0)
 782                         goto nla_put_failure;
 783         return skb->len;
 784
 785 nla_put_failure:
 786         nla_nest_cancel(skb, nest);
 787         return -1;
 788 }
 789
 790 static struct tcf_proto_ops cls_u32_ops __read_mostly = {
 791         .kind           =       "u32",
 792         .classify       =       u32_classify,
 793         .init           =       u32_init,
 794         .destroy        =       u32_destroy,
 795         .get            =       u32_get,
 796         .put            =       u32_put,
 797         .change         =       u32_change,
 798         .delete         =       u32_delete,
 799         .walk           =       u32_walk,
 800         .dump           =       u32_dump,
 801         .owner          =       THIS_MODULE,
 802 };
 803
 804 static int __init init_u32(void)
 805 {
 806         pr_info("u32 classifier\n");
 807 #ifdef CONFIG_CLS_U32_PERF
 808         pr_info("    Performance counters on\n");
 809 #endif
 810 #ifdef CONFIG_NET_CLS_IND
 811         pr_info("    input device check on\n");
 812 #endif
 813 #ifdef CONFIG_NET_CLS_ACT
 814         pr_info("    Actions configured\n");
 815 #endif
 816         return register_tcf_proto_ops(&cls_u32_ops);
 817 }
 818
 819 static void __exit exit_u32(void)
 820 {
 821         unregister_tcf_proto_ops(&cls_u32_ops);
 822 }
 823
 824 module_init(init_u32)
 825 module_exit(exit_u32)
 826 MODULE_LICENSE("GPL");