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
  28 #include <asm/uaccess.h>
  29 #include <asm/system.h>
  30 #include <asm/bitops.h>
  31 #include <linux/config.h>
  32 #include <linux/module.h>
  33 #include <linux/types.h>
  34 #include <linux/kernel.h>
  35 #include <linux/sched.h>
  36 #include <linux/string.h>
  37 #include <linux/mm.h>
  38 #include <linux/socket.h>
  39 #include <linux/sockios.h>
  40 #include <linux/in.h>
  41 #include <linux/errno.h>
  42 #include <linux/interrupt.h>
  43 #include <linux/if_ether.h>
  44 #include <linux/inet.h>
  45 #include <linux/netdevice.h>
  46 #include <linux/etherdevice.h>
  47 #include <linux/notifier.h>
  48 #include <linux/rtnetlink.h>
  49 #include <net/ip.h>
  50 #include <net/route.h>
  51 #include <linux/skbuff.h>
  52 #include <net/sock.h>
  53 #include <net/pkt_sched.h>
  54
  55
  56 struct tc_u_knode
  57 {
  58         struct tc_u_knode       *next;
  59         u32                     handle;
  60         struct tc_u_hnode       *ht_up;
  61 #ifdef CONFIG_NET_CLS_POLICE
  62         struct tcf_police       *police;
  63 #endif
  64         struct tcf_result       res;
  65         struct tc_u_hnode       *ht_down;
  66         struct tc_u32_sel       sel;
  67 };
  68
  69 struct tc_u_hnode
  70 {
  71         struct tc_u_hnode       *next;
  72         u32                     handle;
  73         struct tc_u_common      *tp_c;
  74         int                     refcnt;
  75         unsigned                divisor;
  76         u32                     hgenerator;
  77         struct tc_u_knode       *ht[1];
  78 };
  79
  80 struct tc_u_common
  81 {
  82         struct tc_u_common      *next;
  83         struct tc_u_hnode       *hlist;
  84         struct Qdisc            *q;
  85         int                     refcnt;
  86         u32                     hgenerator;
  87 };
  88
  89 static struct tc_u_common *u32_list;
  90
  91 static __inline__ unsigned u32_hash_fold(u32 key, struct tc_u32_sel *sel)
  92 {
  93         unsigned h = key & sel->hmask;
  94
  95         h ^= h>>16;
  96         h ^= h>>8;
  97         return h;
  98 }
  99
 100 static int u32_classify(struct sk_buff *skb, struct tcf_proto *tp, struct tcf_result *res)
 101 {
 102         struct {
 103                 struct tc_u_knode *knode;
 104                 u8                *ptr;
 105         } stack[TC_U32_MAXDEPTH];
 106
 107         struct tc_u_hnode *ht = (struct tc_u_hnode*)tp->root;
 108         u8 *ptr = skb->nh.raw;
 109         struct tc_u_knode *n;
 110         int sdepth = 0;
 111         int off2 = 0;
 112         int sel = 0;
 113         int i;
 114
 115 next_ht:
 116         n = ht->ht[sel];
 117
 118 next_knode:
 119         if (n) {
 120                 struct tc_u32_key *key = n->sel.keys;
 121
 122                 for (i = n->sel.nkeys; i>0; i--, key++) {
 123                         if ((*(u32*)(ptr+key->off+(off2&key->offmask))^key->val)&key->mask) {
 124                                 n = n->next;
 125                                 goto next_knode;
 126                         }
 127                 }
 128                 if (n->ht_down == NULL) {
 129 check_terminal:
 130                         if (n->sel.flags&TC_U32_TERMINAL) {
 131                                 *res = n->res;
 132 #ifdef CONFIG_NET_CLS_POLICE
 133                                 if (n->police) {
 134                                         int pol_res = tcf_police(skb, n->police);
 135                                         if (pol_res >= 0)
 136                                                 return pol_res;
 137                                 } else
 138 #endif
 139                                         return 0;
 140                         }
 141                         n = n->next;
 142                         goto next_knode;
 143                 }
 144
 145                 /* PUSH */
 146                 if (sdepth >= TC_U32_MAXDEPTH)
 147                         goto deadloop;
 148                 stack[sdepth].knode = n;
 149                 stack[sdepth].ptr = ptr;
 150                 sdepth++;
 151
 152                 ht = n->ht_down;
 153                 sel = 0;
 154                 if (ht->divisor)
 155                         sel = ht->divisor&u32_hash_fold(*(u32*)(ptr+n->sel.hoff), &n->sel);
 156
 157                 if (!(n->sel.flags&(TC_U32_VAROFFSET|TC_U32_OFFSET|TC_U32_EAT)))
 158                         goto next_ht;
 159
 160                 if (n->sel.flags&(TC_U32_OFFSET|TC_U32_VAROFFSET)) {
 161                         off2 = n->sel.off + 3;
 162                         if (n->sel.flags&TC_U32_VAROFFSET)
 163                                 off2 += ntohs(n->sel.offmask & *(u16*)(ptr+n->sel.offoff)) >>n->sel.offshift;
 164                         off2 &= ~3;
 165                 }
 166                 if (n->sel.flags&TC_U32_EAT) {
 167                         ptr += off2;
 168                         off2 = 0;
 169                 }
 170
 171                 if (ptr < skb->tail)
 172                         goto next_ht;
 173         }
 174
 175         /* POP */
 176         if (sdepth--) {
 177                 n = stack[sdepth].knode;
 178                 ht = n->ht_up;
 179                 ptr = stack[sdepth].ptr;
 180                 goto check_terminal;
 181         }
 182         return -1;
 183
 184 deadloop:
 185         if (net_ratelimit())
 186                 printk("cls_u32: dead loop\n");
 187         return -1;
 188 }
 189
 190 static __inline__ struct tc_u_hnode *
 191 u32_lookup_ht(struct tc_u_common *tp_c, u32 handle)
 192 {
 193         struct tc_u_hnode *ht;
 194
 195         for (ht = tp_c->hlist; ht; ht = ht->next)
 196                 if (ht->handle == handle)
 197                         break;
 198
 199         return ht;
 200 }
 201
 202 static __inline__ struct tc_u_knode *
 203 u32_lookup_key(struct tc_u_hnode *ht, u32 handle)
 204 {
 205         unsigned sel;
 206         struct tc_u_knode *n = NULL;
 207
 208         sel = TC_U32_HASH(handle);
 209         if (sel > ht->divisor)
 210                 goto out;
 211
 212         for (n = ht->ht[sel]; n; n = n->next)
 213                 if (n->handle == handle)
 214                         break;
 215 out:
 216         return n;
 217 }
 218
 219
 220 static unsigned long u32_get(struct tcf_proto *tp, u32 handle)
 221 {
 222         struct tc_u_hnode *ht;
 223         struct tc_u_common *tp_c = tp->data;
 224
 225         if (TC_U32_HTID(handle) == TC_U32_ROOT)
 226                 ht = tp->root;
 227         else
 228                 ht = u32_lookup_ht(tp_c, TC_U32_HTID(handle));
 229
 230         if (!ht)
 231                 return 0;
 232
 233         if (TC_U32_KEY(handle) == 0)
 234                 return (unsigned long)ht;
 235
 236         return (unsigned long)u32_lookup_key(ht, handle);
 237 }
 238
 239 static void u32_put(struct tcf_proto *tp, unsigned long f)
 240 {
 241 }
 242
 243 static u32 gen_new_htid(struct tc_u_common *tp_c)
 244 {
 245         int i = 0x800;
 246
 247         do {
 248                 if (++tp_c->hgenerator == 0x7FF)
 249                         tp_c->hgenerator = 1;
 250         } while (--i>0 && u32_lookup_ht(tp_c, (tp_c->hgenerator|0x800)<<20));
 251
 252         return i > 0 ? (tp_c->hgenerator|0x800)<<20 : 0;
 253 }
 254
 255 static int u32_init(struct tcf_proto *tp)
 256 {
 257         struct tc_u_hnode *root_ht;
 258         struct tc_u_common *tp_c;
 259
 260         for (tp_c = u32_list; tp_c; tp_c = tp_c->next)
 261                 if (tp_c->q == tp->q)
 262                         break;
 263
 264         root_ht = kmalloc(sizeof(*root_ht), GFP_KERNEL);
 265         if (root_ht == NULL)
 266                 return -ENOBUFS;
 267
 268         memset(root_ht, 0, sizeof(*root_ht));
 269         root_ht->divisor = 0;
 270         root_ht->refcnt++;
 271         root_ht->handle = tp_c ? gen_new_htid(tp_c) : 0x80000000;
 272
 273         if (tp_c == NULL) {
 274                 tp_c = kmalloc(sizeof(*tp_c), GFP_KERNEL);
 275                 if (tp_c == NULL) {
 276                         kfree(root_ht);
 277                         return -ENOBUFS;
 278                 }
 279                 memset(tp_c, 0, sizeof(*tp_c));
 280                 tp_c->q = tp->q;
 281                 tp_c->next = u32_list;
 282                 u32_list = tp_c;
 283         }
 284
 285         tp_c->refcnt++;
 286         root_ht->next = tp_c->hlist;
 287         tp_c->hlist = root_ht;
 288         root_ht->tp_c = tp_c;
 289
 290         tp->root = root_ht;
 291         tp->data = tp_c;
 292         return 0;
 293 }
 294
 295 static int u32_destroy_key(struct tcf_proto *tp, struct tc_u_knode *n)
 296 {
 297         unsigned long cl;
 298
 299         if ((cl = __cls_set_class(&n->res.class, 0)) != 0)
 300                 tp->q->ops->cl_ops->unbind_tcf(tp->q, cl);
 301 #ifdef CONFIG_NET_CLS_POLICE
 302         tcf_police_release(n->police);
 303 #endif
 304         if (n->ht_down)
 305                 n->ht_down->refcnt--;
 306         kfree(n);
 307         return 0;
 308 }
 309
 310 static int u32_delete_key(struct tcf_proto *tp, struct tc_u_knode* key)
 311 {
 312         struct tc_u_knode **kp;
 313         struct tc_u_hnode *ht = key->ht_up;
 314
 315         if (ht) {
 316                 for (kp = &ht->ht[TC_U32_HASH(key->handle)]; *kp; kp = &(*kp)->next) {
 317                         if (*kp == key) {
 318                                 tcf_tree_lock(tp);
 319                                 *kp = key->next;
 320                                 tcf_tree_unlock(tp);
 321
 322                                 u32_destroy_key(tp, key);
 323                                 return 0;
 324                         }
 325                 }
 326         }
 327         BUG_TRAP(0);
 328         return 0;
 329 }
 330
 331 static void u32_clear_hnode(struct tcf_proto *tp, struct tc_u_hnode *ht)
 332 {
 333         struct tc_u_knode *n;
 334         unsigned h;
 335
 336         for (h=0; h<=ht->divisor; h++) {
 337                 while ((n = ht->ht[h]) != NULL) {
 338                         ht->ht[h] = n->next;
 339
 340                         u32_destroy_key(tp, n);
 341                 }
 342         }
 343 }
 344
 345 static int u32_destroy_hnode(struct tcf_proto *tp, struct tc_u_hnode *ht)
 346 {
 347         struct tc_u_common *tp_c = tp->data;
 348         struct tc_u_hnode **hn;
 349
 350         BUG_TRAP(!ht->refcnt);
 351
 352         u32_clear_hnode(tp, ht);
 353
 354         for (hn = &tp_c->hlist; *hn; hn = &(*hn)->next) {
 355                 if (*hn == ht) {
 356                         *hn = ht->next;
 357                         kfree(ht);
 358                         return 0;
 359                 }
 360         }
 361
 362         BUG_TRAP(0);
 363         return -ENOENT;
 364 }
 365
 366 static void u32_destroy(struct tcf_proto *tp)
 367 {
 368         struct tc_u_common *tp_c = tp->data;
 369         struct tc_u_hnode *root_ht = xchg(&tp->root, NULL);
 370
 371         BUG_TRAP(root_ht != NULL);
 372
 373         if (root_ht && --root_ht->refcnt == 0)
 374                 u32_destroy_hnode(tp, root_ht);
 375
 376         if (--tp_c->refcnt == 0) {
 377                 struct tc_u_hnode *ht;
 378                 struct tc_u_common **tp_cp;
 379
 380                 for (tp_cp = &u32_list; *tp_cp; tp_cp = &(*tp_cp)->next) {
 381                         if (*tp_cp == tp_c) {
 382                                 *tp_cp = tp_c->next;
 383                                 break;
 384                         }
 385                 }
 386
 387                 for (ht=tp_c->hlist; ht; ht = ht->next)
 388                         u32_clear_hnode(tp, ht);
 389
 390                 while ((ht = tp_c->hlist) != NULL) {
 391                         tp_c->hlist = ht->next;
 392
 393                         BUG_TRAP(ht->refcnt == 0);
 394
 395                         kfree(ht);
 396                 };
 397
 398                 kfree(tp_c);
 399         }
 400
 401         tp->data = NULL;
 402 }
 403
 404 static int u32_delete(struct tcf_proto *tp, unsigned long arg)
 405 {
 406         struct tc_u_hnode *ht = (struct tc_u_hnode*)arg;
 407
 408         if (ht == NULL)
 409                 return 0;
 410
 411         if (TC_U32_KEY(ht->handle))
 412                 return u32_delete_key(tp, (struct tc_u_knode*)ht);
 413
 414         if (tp->root == ht)
 415                 return -EINVAL;
 416
 417         if (--ht->refcnt == 0)
 418                 u32_destroy_hnode(tp, ht);
 419
 420         return 0;
 421 }
 422
 423 static u32 gen_new_kid(struct tc_u_hnode *ht, u32 handle)
 424 {
 425         struct tc_u_knode *n;
 426         unsigned i = 0x7FF;
 427
 428         for (n=ht->ht[TC_U32_HASH(handle)]; n; n = n->next)
 429                 if (i < TC_U32_NODE(n->handle))
 430                         i = TC_U32_NODE(n->handle);
 431         i++;
 432
 433         return handle|(i>0xFFF ? 0xFFF : i);
 434 }
 435
 436 static int u32_set_parms(struct Qdisc *q, unsigned long base,
 437                          struct tc_u_hnode *ht,
 438                          struct tc_u_knode *n, struct rtattr **tb,
 439                          struct rtattr *est)
 440 {
 441         if (tb[TCA_U32_LINK-1]) {
 442                 u32 handle = *(u32*)RTA_DATA(tb[TCA_U32_LINK-1]);
 443                 struct tc_u_hnode *ht_down = NULL;
 444
 445                 if (TC_U32_KEY(handle))
 446                         return -EINVAL;
 447
 448                 if (handle) {
 449                         ht_down = u32_lookup_ht(ht->tp_c, handle);
 450
 451                         if (ht_down == NULL)
 452                                 return -EINVAL;
 453                         ht_down->refcnt++;
 454                 }
 455
 456                 sch_tree_lock(q);
 457                 ht_down = xchg(&n->ht_down, ht_down);
 458                 sch_tree_unlock(q);
 459
 460                 if (ht_down)
 461                         ht_down->refcnt--;
 462         }
 463         if (tb[TCA_U32_CLASSID-1]) {
 464                 unsigned long cl;
 465
 466                 n->res.classid = *(u32*)RTA_DATA(tb[TCA_U32_CLASSID-1]);
 467                 sch_tree_lock(q);
 468                 cl = __cls_set_class(&n->res.class, q->ops->cl_ops->bind_tcf(q, base, n->res.classid));
 469                 sch_tree_unlock(q);
 470                 if (cl)
 471                         q->ops->cl_ops->unbind_tcf(q, cl);
 472         }
 473 #ifdef CONFIG_NET_CLS_POLICE
 474         if (tb[TCA_U32_POLICE-1]) {
 475                 struct tcf_police *police = tcf_police_locate(tb[TCA_U32_POLICE-1], est);
 476
 477                 sch_tree_lock(q);
 478                 police = xchg(&n->police, police);
 479                 sch_tree_unlock(q);
 480
 481                 tcf_police_release(police);
 482         }
 483 #endif
 484         return 0;
 485 }
 486
 487 static int u32_change(struct tcf_proto *tp, unsigned long base, u32 handle,
 488                       struct rtattr **tca,
 489                       unsigned long *arg)
 490 {
 491         struct tc_u_common *tp_c = tp->data;
 492         struct tc_u_hnode *ht;
 493         struct tc_u_knode *n;
 494         struct tc_u32_sel *s;
 495         struct rtattr *opt = tca[TCA_OPTIONS-1];
 496         struct rtattr *tb[TCA_U32_MAX];
 497         u32 htid;
 498         int err;
 499
 500         if (opt == NULL)
 501                 return handle ? -EINVAL : 0;
 502
 503         if (rtattr_parse(tb, TCA_U32_MAX, RTA_DATA(opt), RTA_PAYLOAD(opt)) < 0)
 504                 return -EINVAL;
 505
 506         if ((n = (struct tc_u_knode*)*arg) != NULL) {
 507                 if (TC_U32_KEY(n->handle) == 0)
 508                         return -EINVAL;
 509
 510                 return u32_set_parms(tp->q, base, n->ht_up, n, tb, tca[TCA_RATE-1]);
 511         }
 512
 513         if (tb[TCA_U32_DIVISOR-1]) {
 514                 unsigned divisor = *(unsigned*)RTA_DATA(tb[TCA_U32_DIVISOR-1]);
 515
 516                 if (--divisor > 0x100)
 517                         return -EINVAL;
 518                 if (TC_U32_KEY(handle))
 519                         return -EINVAL;
 520                 if (handle == 0) {
 521                         handle = gen_new_htid(tp->data);
 522                         if (handle == 0)
 523                                 return -ENOMEM;
 524                 }
 525                 ht = kmalloc(sizeof(*ht) + divisor*sizeof(void*), GFP_KERNEL);
 526                 if (ht == NULL)
 527                         return -ENOBUFS;
 528                 memset(ht, 0, sizeof(*ht) + divisor*sizeof(void*));
 529                 ht->tp_c = tp_c;
 530                 ht->refcnt = 0;
 531                 ht->divisor = divisor;
 532                 ht->handle = handle;
 533                 ht->next = tp_c->hlist;
 534                 tp_c->hlist = ht;
 535                 *arg = (unsigned long)ht;
 536                 return 0;
 537         }
 538
 539         if (tb[TCA_U32_HASH-1]) {
 540                 htid = *(unsigned*)RTA_DATA(tb[TCA_U32_HASH-1]);
 541                 if (TC_U32_HTID(htid) == TC_U32_ROOT) {
 542                         ht = tp->root;
 543                         htid = ht->handle;
 544                 } else {
 545                         ht = u32_lookup_ht(tp->data, TC_U32_HTID(htid));
 546                         if (ht == NULL)
 547                                 return -EINVAL;
 548                 }
 549         } else {
 550                 ht = tp->root;
 551                 htid = ht->handle;
 552         }
 553
 554         if (ht->divisor < TC_U32_HASH(htid))
 555                 return -EINVAL;
 556
 557         if (handle) {
 558                 if (TC_U32_HTID(handle) && TC_U32_HTID(handle^htid))
 559                         return -EINVAL;
 560                 handle = htid | TC_U32_NODE(handle);
 561         } else
 562                 handle = gen_new_kid(ht, htid);
 563
 564         if (tb[TCA_U32_SEL-1] == 0 ||
 565             RTA_PAYLOAD(tb[TCA_U32_SEL-1]) < sizeof(struct tc_u32_sel))
 566                 return -EINVAL;
 567
 568         s = RTA_DATA(tb[TCA_U32_SEL-1]);
 569         n = kmalloc(sizeof(*n) + s->nkeys*sizeof(struct tc_u32_key), GFP_KERNEL);
 570         if (n == NULL)
 571                 return -ENOBUFS;
 572         memset(n, 0, sizeof(*n) + s->nkeys*sizeof(struct tc_u32_key));
 573         memcpy(&n->sel, s, sizeof(*s) + s->nkeys*sizeof(struct tc_u32_key));
 574         n->ht_up = ht;
 575         n->handle = handle;
 576         err = u32_set_parms(tp->q, base, ht, n, tb, tca[TCA_RATE-1]);
 577         if (err == 0) {
 578                 struct tc_u_knode **ins;
 579                 for (ins = &ht->ht[TC_U32_HASH(handle)]; *ins; ins = &(*ins)->next)
 580                         if (TC_U32_NODE(handle) < TC_U32_NODE((*ins)->handle))
 581                                 break;
 582
 583                 n->next = *ins;
 584                 wmb();
 585                 *ins = n;
 586
 587                 *arg = (unsigned long)n;
 588                 return 0;
 589         }
 590         kfree(n);
 591         return err;
 592 }
 593
 594 static void u32_walk(struct tcf_proto *tp, struct tcf_walker *arg)
 595 {
 596         struct tc_u_common *tp_c = tp->data;
 597         struct tc_u_hnode *ht;
 598         struct tc_u_knode *n;
 599         unsigned h;
 600
 601         if (arg->stop)
 602                 return;
 603
 604         for (ht = tp_c->hlist; ht; ht = ht->next) {
 605                 if (arg->count >= arg->skip) {
 606                         if (arg->fn(tp, (unsigned long)ht, arg) < 0) {
 607                                 arg->stop = 1;
 608                                 return;
 609                         }
 610                 }
 611                 arg->count++;
 612                 for (h = 0; h <= ht->divisor; h++) {
 613                         for (n = ht->ht[h]; n; n = n->next) {
 614                                 if (arg->count < arg->skip) {
 615                                         arg->count++;
 616                                         continue;
 617                                 }
 618                                 if (arg->fn(tp, (unsigned long)n, arg) < 0) {
 619                                         arg->stop = 1;
 620                                         return;
 621                                 }
 622                                 arg->count++;
 623                         }
 624                 }
 625         }
 626 }
 627
 628 static int u32_dump(struct tcf_proto *tp, unsigned long fh,
 629                      struct sk_buff *skb, struct tcmsg *t)
 630 {
 631         struct tc_u_knode *n = (struct tc_u_knode*)fh;
 632         unsigned char    *b = skb->tail;
 633         struct rtattr *rta;
 634
 635         if (n == NULL)
 636                 return skb->len;
 637
 638         t->tcm_handle = n->handle;
 639
 640         rta = (struct rtattr*)b;
 641         RTA_PUT(skb, TCA_OPTIONS, 0, NULL);
 642
 643         if (TC_U32_KEY(n->handle) == 0) {
 644                 struct tc_u_hnode *ht = (struct tc_u_hnode*)fh;
 645                 u32 divisor = ht->divisor+1;
 646                 RTA_PUT(skb, TCA_U32_DIVISOR, 4, &divisor);
 647         } else {
 648                 RTA_PUT(skb, TCA_U32_SEL,
 649                         sizeof(n->sel) + n->sel.nkeys*sizeof(struct tc_u32_key),
 650                         &n->sel);
 651                 if (n->ht_up) {
 652                         u32 htid = n->handle & 0xFFFFF000;
 653                         RTA_PUT(skb, TCA_U32_HASH, 4, &htid);
 654                 }
 655                 if (n->res.classid)
 656                         RTA_PUT(skb, TCA_U32_CLASSID, 4, &n->res.classid);
 657                 if (n->ht_down)
 658                         RTA_PUT(skb, TCA_U32_LINK, 4, &n->ht_down->handle);
 659 #ifdef CONFIG_NET_CLS_POLICE
 660                 if (n->police) {
 661                         struct rtattr * p_rta = (struct rtattr*)skb->tail;
 662
 663                         RTA_PUT(skb, TCA_U32_POLICE, 0, NULL);
 664
 665                         if (tcf_police_dump(skb, n->police) < 0)
 666                                 goto rtattr_failure;
 667
 668                         p_rta->rta_len = skb->tail - (u8*)p_rta;
 669                 }
 670 #endif
 671         }
 672
 673         rta->rta_len = skb->tail - b;
 674 #ifdef CONFIG_NET_CLS_POLICE
 675         if (TC_U32_KEY(n->handle) && n->police) {
 676                 if (qdisc_copy_stats(skb, &n->police->stats))
 677                         goto rtattr_failure;
 678         }
 679 #endif
 680         return skb->len;
 681
 682 rtattr_failure:
 683         skb_trim(skb, b - skb->data);
 684         return -1;
 685 }
 686
 687 static struct tcf_proto_ops cls_u32_ops = {
 688         .next           =       NULL,
 689         .kind           =       "u32",
 690         .classify       =       u32_classify,
 691         .init           =       u32_init,
 692         .destroy        =       u32_destroy,
 693         .get            =       u32_get,
 694         .put            =       u32_put,
 695         .change         =       u32_change,
 696         .delete         =       u32_delete,
 697         .walk           =       u32_walk,
 698         .dump           =       u32_dump,
 699         .owner          =       THIS_MODULE,
 700 };
 701
 702 static int __init init_u32(void)
 703 {
 704         return register_tcf_proto_ops(&cls_u32_ops);
 705 }
 706
 707 static void __exit exit_u32(void)
 708 {
 709         unregister_tcf_proto_ops(&cls_u32_ops);
 710 }
 711
 712 module_init(init_u32)
 713 module_exit(exit_u32)
 714 MODULE_LICENSE("GPL");