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/percpu.h>
  40 #include <linux/rtnetlink.h>
  41 #include <linux/skbuff.h>
  42 #include <linux/bitmap.h>
  43 #include <linux/netdevice.h>
  44 #include <linux/hash.h>
  45 #include <net/netlink.h>
  46 #include <net/act_api.h>
  47 #include <net/pkt_cls.h>
  48 #include <linux/netdevice.h>
  49 #include <linux/idr.h>
  50
  51 struct tc_u_knode {
  52         struct tc_u_knode __rcu *next;
  53         u32                     handle;
  54         struct tc_u_hnode __rcu *ht_up;
  55         struct tcf_exts         exts;
  56 #ifdef CONFIG_NET_CLS_IND
  57         int                     ifindex;
  58 #endif
  59         u8                      fshift;
  60         struct tcf_result       res;
  61         struct tc_u_hnode __rcu *ht_down;
  62 #ifdef CONFIG_CLS_U32_PERF
  63         struct tc_u32_pcnt __percpu *pf;
  64 #endif
  65         u32                     flags;
  66 #ifdef CONFIG_CLS_U32_MARK
  67         u32                     val;
  68         u32                     mask;
  69         u32 __percpu            *pcpu_success;
  70 #endif
  71         struct tcf_proto        *tp;
  72         union {
  73                 struct work_struct      work;
  74                 struct rcu_head         rcu;
  75         };
  76         /* The 'sel' field MUST be the last field in structure to allow for
  77          * tc_u32_keys allocated at end of structure.
  78          */
  79         struct tc_u32_sel       sel;
  80 };
  81
  82 struct tc_u_hnode {
  83         struct tc_u_hnode __rcu *next;
  84         u32                     handle;
  85         u32                     prio;
  86         struct tc_u_common      *tp_c;
  87         int                     refcnt;
  88         unsigned int            divisor;
  89         struct idr              handle_idr;
  90         struct rcu_head         rcu;
  91         /* The 'ht' field MUST be the last field in structure to allow for
  92          * more entries allocated at end of structure.
  93          */
  94         struct tc_u_knode __rcu *ht[1];
  95 };
  96
  97 struct tc_u_common {
  98         struct tc_u_hnode __rcu *hlist;
  99         struct tcf_block        *block;
 100         int                     refcnt;
 101         struct idr              handle_idr;
 102         struct hlist_node       hnode;
 103         struct rcu_head         rcu;
 104 };
 105
 106 static inline unsigned int u32_hash_fold(__be32 key,
 107                                          const struct tc_u32_sel *sel,
 108                                          u8 fshift)
 109 {
 110         unsigned int h = ntohl(key & sel->hmask) >> fshift;
 111
 112         return h;
 113 }
 114
 115 static int u32_classify(struct sk_buff *skb, const struct tcf_proto *tp,
 116                         struct tcf_result *res)
 117 {
 118         struct {
 119                 struct tc_u_knode *knode;
 120                 unsigned int      off;
 121         } stack[TC_U32_MAXDEPTH];
 122
 123         struct tc_u_hnode *ht = rcu_dereference_bh(tp->root);
 124         unsigned int off = skb_network_offset(skb);
 125         struct tc_u_knode *n;
 126         int sdepth = 0;
 127         int off2 = 0;
 128         int sel = 0;
 129 #ifdef CONFIG_CLS_U32_PERF
 130         int j;
 131 #endif
 132         int i, r;
 133
 134 next_ht:
 135         n = rcu_dereference_bh(ht->ht[sel]);
 136
 137 next_knode:
 138         if (n) {
 139                 struct tc_u32_key *key = n->sel.keys;
 140
 141 #ifdef CONFIG_CLS_U32_PERF
 142                 __this_cpu_inc(n->pf->rcnt);
 143                 j = 0;
 144 #endif
 145
 146                 if (tc_skip_sw(n->flags)) {
 147                         n = rcu_dereference_bh(n->next);
 148                         goto next_knode;
 149                 }
 150
 151 #ifdef CONFIG_CLS_U32_MARK
 152                 if ((skb->mark & n->mask) != n->val) {
 153                         n = rcu_dereference_bh(n->next);
 154                         goto next_knode;
 155                 } else {
 156                         __this_cpu_inc(*n->pcpu_success);
 157                 }
 158 #endif
 159
 160                 for (i = n->sel.nkeys; i > 0; i--, key++) {
 161                         int toff = off + key->off + (off2 & key->offmask);
 162                         __be32 *data, hdata;
 163
 164                         if (skb_headroom(skb) + toff > INT_MAX)
 165                                 goto out;
 166
 167                         data = skb_header_pointer(skb, toff, 4, &hdata);
 168                         if (!data)
 169                                 goto out;
 170                         if ((*data ^ key->val) & key->mask) {
 171                                 n = rcu_dereference_bh(n->next);
 172                                 goto next_knode;
 173                         }
 174 #ifdef CONFIG_CLS_U32_PERF
 175                         __this_cpu_inc(n->pf->kcnts[j]);
 176                         j++;
 177 #endif
 178                 }
 179
 180                 ht = rcu_dereference_bh(n->ht_down);
 181                 if (!ht) {
 182 check_terminal:
 183                         if (n->sel.flags & TC_U32_TERMINAL) {
 184
 185                                 *res = n->res;
 186 #ifdef CONFIG_NET_CLS_IND
 187                                 if (!tcf_match_indev(skb, n->ifindex)) {
 188                                         n = rcu_dereference_bh(n->next);
 189                                         goto next_knode;
 190                                 }
 191 #endif
 192 #ifdef CONFIG_CLS_U32_PERF
 193                                 __this_cpu_inc(n->pf->rhit);
 194 #endif
 195                                 r = tcf_exts_exec(skb, &n->exts, res);
 196                                 if (r < 0) {
 197                                         n = rcu_dereference_bh(n->next);
 198                                         goto next_knode;
 199                                 }
 200
 201                                 return r;
 202                         }
 203                         n = rcu_dereference_bh(n->next);
 204                         goto next_knode;
 205                 }
 206
 207                 /* PUSH */
 208                 if (sdepth >= TC_U32_MAXDEPTH)
 209                         goto deadloop;
 210                 stack[sdepth].knode = n;
 211                 stack[sdepth].off = off;
 212                 sdepth++;
 213
 214                 ht = rcu_dereference_bh(n->ht_down);
 215                 sel = 0;
 216                 if (ht->divisor) {
 217                         __be32 *data, hdata;
 218
 219                         data = skb_header_pointer(skb, off + n->sel.hoff, 4,
 220                                                   &hdata);
 221                         if (!data)
 222                                 goto out;
 223                         sel = ht->divisor & u32_hash_fold(*data, &n->sel,
 224                                                           n->fshift);
 225                 }
 226                 if (!(n->sel.flags & (TC_U32_VAROFFSET | TC_U32_OFFSET | TC_U32_EAT)))
 227                         goto next_ht;
 228
 229                 if (n->sel.flags & (TC_U32_OFFSET | TC_U32_VAROFFSET)) {
 230                         off2 = n->sel.off + 3;
 231                         if (n->sel.flags & TC_U32_VAROFFSET) {
 232                                 __be16 *data, hdata;
 233
 234                                 data = skb_header_pointer(skb,
 235                                                           off + n->sel.offoff,
 236                                                           2, &hdata);
 237                                 if (!data)
 238                                         goto out;
 239                                 off2 += ntohs(n->sel.offmask & *data) >>
 240                                         n->sel.offshift;
 241                         }
 242                         off2 &= ~3;
 243                 }
 244                 if (n->sel.flags & TC_U32_EAT) {
 245                         off += off2;
 246                         off2 = 0;
 247                 }
 248
 249                 if (off < skb->len)
 250                         goto next_ht;
 251         }
 252
 253         /* POP */
 254         if (sdepth--) {
 255                 n = stack[sdepth].knode;
 256                 ht = rcu_dereference_bh(n->ht_up);
 257                 off = stack[sdepth].off;
 258                 goto check_terminal;
 259         }
 260 out:
 261         return -1;
 262
 263 deadloop:
 264         net_warn_ratelimited("cls_u32: dead loop\n");
 265         return -1;
 266 }
 267
 268 static struct tc_u_hnode *u32_lookup_ht(struct tc_u_common *tp_c, u32 handle)
 269 {
 270         struct tc_u_hnode *ht;
 271
 272         for (ht = rtnl_dereference(tp_c->hlist);
 273              ht;
 274              ht = rtnl_dereference(ht->next))
 275                 if (ht->handle == handle)
 276                         break;
 277
 278         return ht;
 279 }
 280
 281 static struct tc_u_knode *u32_lookup_key(struct tc_u_hnode *ht, u32 handle)
 282 {
 283         unsigned int sel;
 284         struct tc_u_knode *n = NULL;
 285
 286         sel = TC_U32_HASH(handle);
 287         if (sel > ht->divisor)
 288                 goto out;
 289
 290         for (n = rtnl_dereference(ht->ht[sel]);
 291              n;
 292              n = rtnl_dereference(n->next))
 293                 if (n->handle == handle)
 294                         break;
 295 out:
 296         return n;
 297 }
 298
 299
 300 static void *u32_get(struct tcf_proto *tp, u32 handle)
 301 {
 302         struct tc_u_hnode *ht;
 303         struct tc_u_common *tp_c = tp->data;
 304
 305         if (TC_U32_HTID(handle) == TC_U32_ROOT)
 306                 ht = rtnl_dereference(tp->root);
 307         else
 308                 ht = u32_lookup_ht(tp_c, TC_U32_HTID(handle));
 309
 310         if (!ht)
 311                 return NULL;
 312
 313         if (TC_U32_KEY(handle) == 0)
 314                 return ht;
 315
 316         return u32_lookup_key(ht, handle);
 317 }
 318
 319 static u32 gen_new_htid(struct tc_u_common *tp_c, struct tc_u_hnode *ptr)
 320 {
 321         unsigned long idr_index;
 322         int err;
 323
 324         /* This is only used inside rtnl lock it is safe to increment
 325          * without read _copy_ update semantics
 326          */
 327         err = idr_alloc_ext(&tp_c->handle_idr, ptr, &idr_index,
 328                             1, 0x7FF, GFP_KERNEL);
 329         if (err)
 330                 return 0;
 331         return (u32)(idr_index | 0x800) << 20;
 332 }
 333
 334 static struct hlist_head *tc_u_common_hash;
 335
 336 #define U32_HASH_SHIFT 10
 337 #define U32_HASH_SIZE (1 << U32_HASH_SHIFT)
 338
 339 static unsigned int tc_u_hash(const struct tcf_proto *tp)
 340 {
 341         return hash_ptr(tp->chain->block, U32_HASH_SHIFT);
 342 }
 343
 344 static struct tc_u_common *tc_u_common_find(const struct tcf_proto *tp)
 345 {
 346         struct tc_u_common *tc;
 347         unsigned int h;
 348
 349         h = tc_u_hash(tp);
 350         hlist_for_each_entry(tc, &tc_u_common_hash[h], hnode) {
 351                 if (tc->block == tp->chain->block)
 352                         return tc;
 353         }
 354         return NULL;
 355 }
 356
 357 static int u32_init(struct tcf_proto *tp)
 358 {
 359         struct tc_u_hnode *root_ht;
 360         struct tc_u_common *tp_c;
 361         unsigned int h;
 362
 363         tp_c = tc_u_common_find(tp);
 364
 365         root_ht = kzalloc(sizeof(*root_ht), GFP_KERNEL);
 366         if (root_ht == NULL)
 367                 return -ENOBUFS;
 368
 369         root_ht->refcnt++;
 370         root_ht->handle = tp_c ? gen_new_htid(tp_c, root_ht) : 0x80000000;
 371         root_ht->prio = tp->prio;
 372         idr_init(&root_ht->handle_idr);
 373
 374         if (tp_c == NULL) {
 375                 tp_c = kzalloc(sizeof(*tp_c), GFP_KERNEL);
 376                 if (tp_c == NULL) {
 377                         kfree(root_ht);
 378                         return -ENOBUFS;
 379                 }
 380                 tp_c->block = tp->chain->block;
 381                 INIT_HLIST_NODE(&tp_c->hnode);
 382                 idr_init(&tp_c->handle_idr);
 383
 384                 h = tc_u_hash(tp);
 385                 hlist_add_head(&tp_c->hnode, &tc_u_common_hash[h]);
 386         }
 387
 388         tp_c->refcnt++;
 389         RCU_INIT_POINTER(root_ht->next, tp_c->hlist);
 390         rcu_assign_pointer(tp_c->hlist, root_ht);
 391         root_ht->tp_c = tp_c;
 392
 393         rcu_assign_pointer(tp->root, root_ht);
 394         tp->data = tp_c;
 395         return 0;
 396 }
 397
 398 static int u32_destroy_key(struct tcf_proto *tp, struct tc_u_knode *n,
 399                            bool free_pf)
 400 {
 401         tcf_exts_destroy(&n->exts);
 402         tcf_exts_put_net(&n->exts);
 403         if (n->ht_down)
 404                 n->ht_down->refcnt--;
 405 #ifdef CONFIG_CLS_U32_PERF
 406         if (free_pf)
 407                 free_percpu(n->pf);
 408 #endif
 409 #ifdef CONFIG_CLS_U32_MARK
 410         if (free_pf)
 411                 free_percpu(n->pcpu_success);
 412 #endif
 413         kfree(n);
 414         return 0;
 415 }
 416
 417 /* u32_delete_key_rcu should be called when free'ing a copied
 418  * version of a tc_u_knode obtained from u32_init_knode(). When
 419  * copies are obtained from u32_init_knode() the statistics are
 420  * shared between the old and new copies to allow readers to
 421  * continue to update the statistics during the copy. To support
 422  * this the u32_delete_key_rcu variant does not free the percpu
 423  * statistics.
 424  */
 425 static void u32_delete_key_work(struct work_struct *work)
 426 {
 427         struct tc_u_knode *key = container_of(work, struct tc_u_knode, work);
 428
 429         rtnl_lock();
 430         u32_destroy_key(key->tp, key, false);
 431         rtnl_unlock();
 432 }
 433
 434 static void u32_delete_key_rcu(struct rcu_head *rcu)
 435 {
 436         struct tc_u_knode *key = container_of(rcu, struct tc_u_knode, rcu);
 437
 438         INIT_WORK(&key->work, u32_delete_key_work);
 439         tcf_queue_work(&key->work);
 440 }
 441
 442 /* u32_delete_key_freepf_rcu is the rcu callback variant
 443  * that free's the entire structure including the statistics
 444  * percpu variables. Only use this if the key is not a copy
 445  * returned by u32_init_knode(). See u32_delete_key_rcu()
 446  * for the variant that should be used with keys return from
 447  * u32_init_knode()
 448  */
 449 static void u32_delete_key_freepf_work(struct work_struct *work)
 450 {
 451         struct tc_u_knode *key = container_of(work, struct tc_u_knode, work);
 452
 453         rtnl_lock();
 454         u32_destroy_key(key->tp, key, true);
 455         rtnl_unlock();
 456 }
 457
 458 static void u32_delete_key_freepf_rcu(struct rcu_head *rcu)
 459 {
 460         struct tc_u_knode *key = container_of(rcu, struct tc_u_knode, rcu);
 461
 462         INIT_WORK(&key->work, u32_delete_key_freepf_work);
 463         tcf_queue_work(&key->work);
 464 }
 465
 466 static int u32_delete_key(struct tcf_proto *tp, struct tc_u_knode *key)
 467 {
 468         struct tc_u_knode __rcu **kp;
 469         struct tc_u_knode *pkp;
 470         struct tc_u_hnode *ht = rtnl_dereference(key->ht_up);
 471
 472         if (ht) {
 473                 kp = &ht->ht[TC_U32_HASH(key->handle)];
 474                 for (pkp = rtnl_dereference(*kp); pkp;
 475                      kp = &pkp->next, pkp = rtnl_dereference(*kp)) {
 476                         if (pkp == key) {
 477                                 RCU_INIT_POINTER(*kp, key->next);
 478
 479                                 tcf_unbind_filter(tp, &key->res);
 480                                 tcf_exts_get_net(&key->exts);
 481                                 call_rcu(&key->rcu, u32_delete_key_freepf_rcu);
 482                                 return 0;
 483                         }
 484                 }
 485         }
 486         WARN_ON(1);
 487         return 0;
 488 }
 489
 490 static void u32_clear_hw_hnode(struct tcf_proto *tp, struct tc_u_hnode *h)
 491 {
 492         struct tcf_block *block = tp->chain->block;
 493         struct tc_cls_u32_offload cls_u32 = {};
 494
 495         tc_cls_common_offload_init(&cls_u32.common, tp);
 496         cls_u32.command = TC_CLSU32_DELETE_HNODE;
 497         cls_u32.hnode.divisor = h->divisor;
 498         cls_u32.hnode.handle = h->handle;
 499         cls_u32.hnode.prio = h->prio;
 500
 501         tc_setup_cb_call(block, NULL, TC_SETUP_CLSU32, &cls_u32, false);
 502 }
 503
 504 static int u32_replace_hw_hnode(struct tcf_proto *tp, struct tc_u_hnode *h,
 505                                 u32 flags)
 506 {
 507         struct tcf_block *block = tp->chain->block;
 508         struct tc_cls_u32_offload cls_u32 = {};
 509         bool skip_sw = tc_skip_sw(flags);
 510         bool offloaded = false;
 511         int err;
 512
 513         tc_cls_common_offload_init(&cls_u32.common, tp);
 514         cls_u32.command = TC_CLSU32_NEW_HNODE;
 515         cls_u32.hnode.divisor = h->divisor;
 516         cls_u32.hnode.handle = h->handle;
 517         cls_u32.hnode.prio = h->prio;
 518
 519         err = tc_setup_cb_call(block, NULL, TC_SETUP_CLSU32, &cls_u32, skip_sw);
 520         if (err < 0) {
 521                 u32_clear_hw_hnode(tp, h);
 522                 return err;
 523         } else if (err > 0) {
 524                 offloaded = true;
 525         }
 526
 527         if (skip_sw && !offloaded)
 528                 return -EINVAL;
 529
 530         return 0;
 531 }
 532
 533 static void u32_remove_hw_knode(struct tcf_proto *tp, u32 handle)
 534 {
 535         struct tcf_block *block = tp->chain->block;
 536         struct tc_cls_u32_offload cls_u32 = {};
 537
 538         tc_cls_common_offload_init(&cls_u32.common, tp);
 539         cls_u32.command = TC_CLSU32_DELETE_KNODE;
 540         cls_u32.knode.handle = handle;
 541
 542         tc_setup_cb_call(block, NULL, TC_SETUP_CLSU32, &cls_u32, false);
 543 }
 544
 545 static int u32_replace_hw_knode(struct tcf_proto *tp, struct tc_u_knode *n,
 546                                 u32 flags)
 547 {
 548         struct tcf_block *block = tp->chain->block;
 549         struct tc_cls_u32_offload cls_u32 = {};
 550         bool skip_sw = tc_skip_sw(flags);
 551         int err;
 552
 553         tc_cls_common_offload_init(&cls_u32.common, tp);
 554         cls_u32.command = TC_CLSU32_REPLACE_KNODE;
 555         cls_u32.knode.handle = n->handle;
 556         cls_u32.knode.fshift = n->fshift;
 557 #ifdef CONFIG_CLS_U32_MARK
 558         cls_u32.knode.val = n->val;
 559         cls_u32.knode.mask = n->mask;
 560 #else
 561         cls_u32.knode.val = 0;
 562         cls_u32.knode.mask = 0;
 563 #endif
 564         cls_u32.knode.sel = &n->sel;
 565         cls_u32.knode.exts = &n->exts;
 566         if (n->ht_down)
 567                 cls_u32.knode.link_handle = n->ht_down->handle;
 568
 569         err = tc_setup_cb_call(block, NULL, TC_SETUP_CLSU32, &cls_u32, skip_sw);
 570         if (err < 0) {
 571                 u32_remove_hw_knode(tp, n->handle);
 572                 return err;
 573         } else if (err > 0) {
 574                 n->flags |= TCA_CLS_FLAGS_IN_HW;
 575         }
 576
 577         if (skip_sw && !(n->flags & TCA_CLS_FLAGS_IN_HW))
 578                 return -EINVAL;
 579
 580         return 0;
 581 }
 582
 583 static void u32_clear_hnode(struct tcf_proto *tp, struct tc_u_hnode *ht)
 584 {
 585         struct tc_u_knode *n;
 586         unsigned int h;
 587
 588         for (h = 0; h <= ht->divisor; h++) {
 589                 while ((n = rtnl_dereference(ht->ht[h])) != NULL) {
 590                         RCU_INIT_POINTER(ht->ht[h],
 591                                          rtnl_dereference(n->next));
 592                         tcf_unbind_filter(tp, &n->res);
 593                         u32_remove_hw_knode(tp, n->handle);
 594                         idr_remove_ext(&ht->handle_idr, n->handle);
 595                         if (tcf_exts_get_net(&n->exts))
 596                                 call_rcu(&n->rcu, u32_delete_key_freepf_rcu);
 597                         else
 598                                 u32_destroy_key(n->tp, n, true);
 599                 }
 600         }
 601 }
 602
 603 static int u32_destroy_hnode(struct tcf_proto *tp, struct tc_u_hnode *ht)
 604 {
 605         struct tc_u_common *tp_c = tp->data;
 606         struct tc_u_hnode __rcu **hn;
 607         struct tc_u_hnode *phn;
 608
 609         WARN_ON(ht->refcnt);
 610
 611         u32_clear_hnode(tp, ht);
 612
 613         hn = &tp_c->hlist;
 614         for (phn = rtnl_dereference(*hn);
 615              phn;
 616              hn = &phn->next, phn = rtnl_dereference(*hn)) {
 617                 if (phn == ht) {
 618                         u32_clear_hw_hnode(tp, ht);
 619                         idr_destroy(&ht->handle_idr);
 620                         idr_remove_ext(&tp_c->handle_idr, ht->handle);
 621                         RCU_INIT_POINTER(*hn, ht->next);
 622                         kfree_rcu(ht, rcu);
 623                         return 0;
 624                 }
 625         }
 626
 627         return -ENOENT;
 628 }
 629
 630 static bool ht_empty(struct tc_u_hnode *ht)
 631 {
 632         unsigned int h;
 633
 634         for (h = 0; h <= ht->divisor; h++)
 635                 if (rcu_access_pointer(ht->ht[h]))
 636                         return false;
 637
 638         return true;
 639 }
 640
 641 static void u32_destroy(struct tcf_proto *tp)
 642 {
 643         struct tc_u_common *tp_c = tp->data;
 644         struct tc_u_hnode *root_ht = rtnl_dereference(tp->root);
 645
 646         WARN_ON(root_ht == NULL);
 647
 648         if (root_ht && --root_ht->refcnt == 0)
 649                 u32_destroy_hnode(tp, root_ht);
 650
 651         if (--tp_c->refcnt == 0) {
 652                 struct tc_u_hnode *ht;
 653
 654                 hlist_del(&tp_c->hnode);
 655
 656                 for (ht = rtnl_dereference(tp_c->hlist);
 657                      ht;
 658                      ht = rtnl_dereference(ht->next)) {
 659                         ht->refcnt--;
 660                         u32_clear_hnode(tp, ht);
 661                 }
 662
 663                 while ((ht = rtnl_dereference(tp_c->hlist)) != NULL) {
 664                         RCU_INIT_POINTER(tp_c->hlist, ht->next);
 665                         kfree_rcu(ht, rcu);
 666                 }
 667
 668                 idr_destroy(&tp_c->handle_idr);
 669                 kfree(tp_c);
 670         }
 671
 672         tp->data = NULL;
 673 }
 674
 675 static int u32_delete(struct tcf_proto *tp, void *arg, bool *last)
 676 {
 677         struct tc_u_hnode *ht = arg;
 678         struct tc_u_hnode *root_ht = rtnl_dereference(tp->root);
 679         struct tc_u_common *tp_c = tp->data;
 680         int ret = 0;
 681
 682         if (ht == NULL)
 683                 goto out;
 684
 685         if (TC_U32_KEY(ht->handle)) {
 686                 u32_remove_hw_knode(tp, ht->handle);
 687                 ret = u32_delete_key(tp, (struct tc_u_knode *)ht);
 688                 goto out;
 689         }
 690
 691         if (root_ht == ht)
 692                 return -EINVAL;
 693
 694         if (ht->refcnt == 1) {
 695                 ht->refcnt--;
 696                 u32_destroy_hnode(tp, ht);
 697         } else {
 698                 return -EBUSY;
 699         }
 700
 701 out:
 702         *last = true;
 703         if (root_ht) {
 704                 if (root_ht->refcnt > 1) {
 705                         *last = false;
 706                         goto ret;
 707                 }
 708                 if (root_ht->refcnt == 1) {
 709                         if (!ht_empty(root_ht)) {
 710                                 *last = false;
 711                                 goto ret;
 712                         }
 713                 }
 714         }
 715
 716         if (tp_c->refcnt > 1) {
 717                 *last = false;
 718                 goto ret;
 719         }
 720
 721         if (tp_c->refcnt == 1) {
 722                 struct tc_u_hnode *ht;
 723
 724                 for (ht = rtnl_dereference(tp_c->hlist);
 725                      ht;
 726                      ht = rtnl_dereference(ht->next))
 727                         if (!ht_empty(ht)) {
 728                                 *last = false;
 729                                 break;
 730                         }
 731         }
 732
 733 ret:
 734         return ret;
 735 }
 736
 737 static u32 gen_new_kid(struct tc_u_hnode *ht, u32 htid)
 738 {
 739         unsigned long idr_index;
 740         u32 start = htid | 0x800;
 741         u32 max = htid | 0xFFF;
 742         u32 min = htid;
 743
 744         if (idr_alloc_ext(&ht->handle_idr, NULL, &idr_index,
 745                           start, max + 1, GFP_KERNEL)) {
 746                 if (idr_alloc_ext(&ht->handle_idr, NULL, &idr_index,
 747                                   min + 1, max + 1, GFP_KERNEL))
 748                         return max;
 749         }
 750
 751         return (u32)idr_index;
 752 }
 753
 754 static const struct nla_policy u32_policy[TCA_U32_MAX + 1] = {
 755         [TCA_U32_CLASSID]       = { .type = NLA_U32 },
 756         [TCA_U32_HASH]          = { .type = NLA_U32 },
 757         [TCA_U32_LINK]          = { .type = NLA_U32 },
 758         [TCA_U32_DIVISOR]       = { .type = NLA_U32 },
 759         [TCA_U32_SEL]           = { .len = sizeof(struct tc_u32_sel) },
 760         [TCA_U32_INDEV]         = { .type = NLA_STRING, .len = IFNAMSIZ },
 761         [TCA_U32_MARK]          = { .len = sizeof(struct tc_u32_mark) },
 762         [TCA_U32_FLAGS]         = { .type = NLA_U32 },
 763 };
 764
 765 static int u32_set_parms(struct net *net, struct tcf_proto *tp,
 766                          unsigned long base, struct tc_u_hnode *ht,
 767                          struct tc_u_knode *n, struct nlattr **tb,
 768                          struct nlattr *est, bool ovr)
 769 {
 770         int err;
 771
 772         err = tcf_exts_validate(net, tp, tb, est, &n->exts, ovr);
 773         if (err < 0)
 774                 return err;
 775
 776         if (tb[TCA_U32_LINK]) {
 777                 u32 handle = nla_get_u32(tb[TCA_U32_LINK]);
 778                 struct tc_u_hnode *ht_down = NULL, *ht_old;
 779
 780                 if (TC_U32_KEY(handle))
 781                         return -EINVAL;
 782
 783                 if (handle) {
 784                         ht_down = u32_lookup_ht(ht->tp_c, handle);
 785
 786                         if (ht_down == NULL)
 787                                 return -EINVAL;
 788                         ht_down->refcnt++;
 789                 }
 790
 791                 ht_old = rtnl_dereference(n->ht_down);
 792                 rcu_assign_pointer(n->ht_down, ht_down);
 793
 794                 if (ht_old)
 795                         ht_old->refcnt--;
 796         }
 797         if (tb[TCA_U32_CLASSID]) {
 798                 n->res.classid = nla_get_u32(tb[TCA_U32_CLASSID]);
 799                 tcf_bind_filter(tp, &n->res, base);
 800         }
 801
 802 #ifdef CONFIG_NET_CLS_IND
 803         if (tb[TCA_U32_INDEV]) {
 804                 int ret;
 805                 ret = tcf_change_indev(net, tb[TCA_U32_INDEV]);
 806                 if (ret < 0)
 807                         return -EINVAL;
 808                 n->ifindex = ret;
 809         }
 810 #endif
 811         return 0;
 812 }
 813
 814 static void u32_replace_knode(struct tcf_proto *tp, struct tc_u_common *tp_c,
 815                               struct tc_u_knode *n)
 816 {
 817         struct tc_u_knode __rcu **ins;
 818         struct tc_u_knode *pins;
 819         struct tc_u_hnode *ht;
 820
 821         if (TC_U32_HTID(n->handle) == TC_U32_ROOT)
 822                 ht = rtnl_dereference(tp->root);
 823         else
 824                 ht = u32_lookup_ht(tp_c, TC_U32_HTID(n->handle));
 825
 826         ins = &ht->ht[TC_U32_HASH(n->handle)];
 827
 828         /* The node must always exist for it to be replaced if this is not the
 829          * case then something went very wrong elsewhere.
 830          */
 831         for (pins = rtnl_dereference(*ins); ;
 832              ins = &pins->next, pins = rtnl_dereference(*ins))
 833                 if (pins->handle == n->handle)
 834                         break;
 835
 836         idr_replace_ext(&ht->handle_idr, n, n->handle);
 837         RCU_INIT_POINTER(n->next, pins->next);
 838         rcu_assign_pointer(*ins, n);
 839 }
 840
 841 static struct tc_u_knode *u32_init_knode(struct tcf_proto *tp,
 842                                          struct tc_u_knode *n)
 843 {
 844         struct tc_u_knode *new;
 845         struct tc_u32_sel *s = &n->sel;
 846
 847         new = kzalloc(sizeof(*n) + s->nkeys*sizeof(struct tc_u32_key),
 848                       GFP_KERNEL);
 849
 850         if (!new)
 851                 return NULL;
 852
 853         RCU_INIT_POINTER(new->next, n->next);
 854         new->handle = n->handle;
 855         RCU_INIT_POINTER(new->ht_up, n->ht_up);
 856
 857 #ifdef CONFIG_NET_CLS_IND
 858         new->ifindex = n->ifindex;
 859 #endif
 860         new->fshift = n->fshift;
 861         new->res = n->res;
 862         new->flags = n->flags;
 863         RCU_INIT_POINTER(new->ht_down, n->ht_down);
 864
 865         /* bump reference count as long as we hold pointer to structure */
 866         if (new->ht_down)
 867                 new->ht_down->refcnt++;
 868
 869 #ifdef CONFIG_CLS_U32_PERF
 870         /* Statistics may be incremented by readers during update
 871          * so we must keep them in tact. When the node is later destroyed
 872          * a special destroy call must be made to not free the pf memory.
 873          */
 874         new->pf = n->pf;
 875 #endif
 876
 877 #ifdef CONFIG_CLS_U32_MARK
 878         new->val = n->val;
 879         new->mask = n->mask;
 880         /* Similarly success statistics must be moved as pointers */
 881         new->pcpu_success = n->pcpu_success;
 882 #endif
 883         new->tp = tp;
 884         memcpy(&new->sel, s, sizeof(*s) + s->nkeys*sizeof(struct tc_u32_key));
 885
 886         if (tcf_exts_init(&new->exts, TCA_U32_ACT, TCA_U32_POLICE)) {
 887                 kfree(new);
 888                 return NULL;
 889         }
 890
 891         return new;
 892 }
 893
 894 static int u32_change(struct net *net, struct sk_buff *in_skb,
 895                       struct tcf_proto *tp, unsigned long base, u32 handle,
 896                       struct nlattr **tca, void **arg, bool ovr)
 897 {
 898         struct tc_u_common *tp_c = tp->data;
 899         struct tc_u_hnode *ht;
 900         struct tc_u_knode *n;
 901         struct tc_u32_sel *s;
 902         struct nlattr *opt = tca[TCA_OPTIONS];
 903         struct nlattr *tb[TCA_U32_MAX + 1];
 904         u32 htid, flags = 0;
 905         int err;
 906 #ifdef CONFIG_CLS_U32_PERF
 907         size_t size;
 908 #endif
 909
 910         if (opt == NULL)
 911                 return handle ? -EINVAL : 0;
 912
 913         err = nla_parse_nested(tb, TCA_U32_MAX, opt, u32_policy, NULL);
 914         if (err < 0)
 915                 return err;
 916
 917         if (tb[TCA_U32_FLAGS]) {
 918                 flags = nla_get_u32(tb[TCA_U32_FLAGS]);
 919                 if (!tc_flags_valid(flags))
 920                         return -EINVAL;
 921         }
 922
 923         n = *arg;
 924         if (n) {
 925                 struct tc_u_knode *new;
 926
 927                 if (TC_U32_KEY(n->handle) == 0)
 928                         return -EINVAL;
 929
 930                 if (n->flags != flags)
 931                         return -EINVAL;
 932
 933                 new = u32_init_knode(tp, n);
 934                 if (!new)
 935                         return -ENOMEM;
 936
 937                 err = u32_set_parms(net, tp, base,
 938                                     rtnl_dereference(n->ht_up), new, tb,
 939                                     tca[TCA_RATE], ovr);
 940
 941                 if (err) {
 942                         u32_destroy_key(tp, new, false);
 943                         return err;
 944                 }
 945
 946                 err = u32_replace_hw_knode(tp, new, flags);
 947                 if (err) {
 948                         u32_destroy_key(tp, new, false);
 949                         return err;
 950                 }
 951
 952                 if (!tc_in_hw(new->flags))
 953                         new->flags |= TCA_CLS_FLAGS_NOT_IN_HW;
 954
 955                 u32_replace_knode(tp, tp_c, new);
 956                 tcf_unbind_filter(tp, &n->res);
 957                 tcf_exts_get_net(&n->exts);
 958                 call_rcu(&n->rcu, u32_delete_key_rcu);
 959                 return 0;
 960         }
 961
 962         if (tb[TCA_U32_DIVISOR]) {
 963                 unsigned int divisor = nla_get_u32(tb[TCA_U32_DIVISOR]);
 964
 965                 if (--divisor > 0x100)
 966                         return -EINVAL;
 967                 if (TC_U32_KEY(handle))
 968                         return -EINVAL;
 969                 ht = kzalloc(sizeof(*ht) + divisor*sizeof(void *), GFP_KERNEL);
 970                 if (ht == NULL)
 971                         return -ENOBUFS;
 972                 if (handle == 0) {
 973                         handle = gen_new_htid(tp->data, ht);
 974                         if (handle == 0) {
 975                                 kfree(ht);
 976                                 return -ENOMEM;
 977                         }
 978                 } else {
 979                         err = idr_alloc_ext(&tp_c->handle_idr, ht, NULL,
 980                                             handle, handle + 1, GFP_KERNEL);
 981                         if (err) {
 982                                 kfree(ht);
 983                                 return err;
 984                         }
 985                 }
 986                 ht->tp_c = tp_c;
 987                 ht->refcnt = 1;
 988                 ht->divisor = divisor;
 989                 ht->handle = handle;
 990                 ht->prio = tp->prio;
 991                 idr_init(&ht->handle_idr);
 992
 993                 err = u32_replace_hw_hnode(tp, ht, flags);
 994                 if (err) {
 995                         idr_remove_ext(&tp_c->handle_idr, handle);
 996                         kfree(ht);
 997                         return err;
 998                 }
 999
1000                 RCU_INIT_POINTER(ht->next, tp_c->hlist);
1001                 rcu_assign_pointer(tp_c->hlist, ht);
1002                 *arg = ht;
1003
1004                 return 0;
1005         }
1006
1007         if (tb[TCA_U32_HASH]) {
1008                 htid = nla_get_u32(tb[TCA_U32_HASH]);
1009                 if (TC_U32_HTID(htid) == TC_U32_ROOT) {
1010                         ht = rtnl_dereference(tp->root);
1011                         htid = ht->handle;
1012                 } else {
1013                         ht = u32_lookup_ht(tp->data, TC_U32_HTID(htid));
1014                         if (ht == NULL)
1015                                 return -EINVAL;
1016                 }
1017         } else {
1018                 ht = rtnl_dereference(tp->root);
1019                 htid = ht->handle;
1020         }
1021
1022         if (ht->divisor < TC_U32_HASH(htid))
1023                 return -EINVAL;
1024
1025         if (handle) {
1026                 if (TC_U32_HTID(handle) && TC_U32_HTID(handle^htid))
1027                         return -EINVAL;
1028                 handle = htid | TC_U32_NODE(handle);
1029                 err = idr_alloc_ext(&ht->handle_idr, NULL, NULL,
1030                                     handle, handle + 1,
1031                                     GFP_KERNEL);
1032                 if (err)
1033                         return err;
1034         } else
1035                 handle = gen_new_kid(ht, htid);
1036
1037         if (tb[TCA_U32_SEL] == NULL) {
1038                 err = -EINVAL;
1039                 goto erridr;
1040         }
1041
1042         s = nla_data(tb[TCA_U32_SEL]);
1043
1044         n = kzalloc(sizeof(*n) + s->nkeys*sizeof(struct tc_u32_key), GFP_KERNEL);
1045         if (n == NULL) {
1046                 err = -ENOBUFS;
1047                 goto erridr;
1048         }
1049
1050 #ifdef CONFIG_CLS_U32_PERF
1051         size = sizeof(struct tc_u32_pcnt) + s->nkeys * sizeof(u64);
1052         n->pf = __alloc_percpu(size, __alignof__(struct tc_u32_pcnt));
1053         if (!n->pf) {
1054                 err = -ENOBUFS;
1055                 goto errfree;
1056         }
1057 #endif
1058
1059         memcpy(&n->sel, s, sizeof(*s) + s->nkeys*sizeof(struct tc_u32_key));
1060         RCU_INIT_POINTER(n->ht_up, ht);
1061         n->handle = handle;
1062         n->fshift = s->hmask ? ffs(ntohl(s->hmask)) - 1 : 0;
1063         n->flags = flags;
1064         n->tp = tp;
1065
1066         err = tcf_exts_init(&n->exts, TCA_U32_ACT, TCA_U32_POLICE);
1067         if (err < 0)
1068                 goto errout;
1069
1070 #ifdef CONFIG_CLS_U32_MARK
1071         n->pcpu_success = alloc_percpu(u32);
1072         if (!n->pcpu_success) {
1073                 err = -ENOMEM;
1074                 goto errout;
1075         }
1076
1077         if (tb[TCA_U32_MARK]) {
1078                 struct tc_u32_mark *mark;
1079
1080                 mark = nla_data(tb[TCA_U32_MARK]);
1081                 n->val = mark->val;
1082                 n->mask = mark->mask;
1083         }
1084 #endif
1085
1086         err = u32_set_parms(net, tp, base, ht, n, tb, tca[TCA_RATE], ovr);
1087         if (err == 0) {
1088                 struct tc_u_knode __rcu **ins;
1089                 struct tc_u_knode *pins;
1090
1091                 err = u32_replace_hw_knode(tp, n, flags);
1092                 if (err)
1093                         goto errhw;
1094
1095                 if (!tc_in_hw(n->flags))
1096                         n->flags |= TCA_CLS_FLAGS_NOT_IN_HW;
1097
1098                 ins = &ht->ht[TC_U32_HASH(handle)];
1099                 for (pins = rtnl_dereference(*ins); pins;
1100                      ins = &pins->next, pins = rtnl_dereference(*ins))
1101                         if (TC_U32_NODE(handle) < TC_U32_NODE(pins->handle))
1102                                 break;
1103
1104                 RCU_INIT_POINTER(n->next, pins);
1105                 rcu_assign_pointer(*ins, n);
1106                 *arg = n;
1107                 return 0;
1108         }
1109
1110 errhw:
1111 #ifdef CONFIG_CLS_U32_MARK
1112         free_percpu(n->pcpu_success);
1113 #endif
1114
1115 errout:
1116         tcf_exts_destroy(&n->exts);
1117 #ifdef CONFIG_CLS_U32_PERF
1118 errfree:
1119         free_percpu(n->pf);
1120 #endif
1121         kfree(n);
1122 erridr:
1123         idr_remove_ext(&ht->handle_idr, handle);
1124         return err;
1125 }
1126
1127 static void u32_walk(struct tcf_proto *tp, struct tcf_walker *arg)
1128 {
1129         struct tc_u_common *tp_c = tp->data;
1130         struct tc_u_hnode *ht;
1131         struct tc_u_knode *n;
1132         unsigned int h;
1133
1134         if (arg->stop)
1135                 return;
1136
1137         for (ht = rtnl_dereference(tp_c->hlist);
1138              ht;
1139              ht = rtnl_dereference(ht->next)) {
1140                 if (ht->prio != tp->prio)
1141                         continue;
1142                 if (arg->count >= arg->skip) {
1143                         if (arg->fn(tp, ht, arg) < 0) {
1144                                 arg->stop = 1;
1145                                 return;
1146                         }
1147                 }
1148                 arg->count++;
1149                 for (h = 0; h <= ht->divisor; h++) {
1150                         for (n = rtnl_dereference(ht->ht[h]);
1151                              n;
1152                              n = rtnl_dereference(n->next)) {
1153                                 if (arg->count < arg->skip) {
1154                                         arg->count++;
1155                                         continue;
1156                                 }
1157                                 if (arg->fn(tp, n, arg) < 0) {
1158                                         arg->stop = 1;
1159                                         return;
1160                                 }
1161                                 arg->count++;
1162                         }
1163                 }
1164         }
1165 }
1166
1167 static void u32_bind_class(void *fh, u32 classid, unsigned long cl)
1168 {
1169         struct tc_u_knode *n = fh;
1170
1171         if (n && n->res.classid == classid)
1172                 n->res.class = cl;
1173 }
1174
1175 static int u32_dump(struct net *net, struct tcf_proto *tp, void *fh,
1176                     struct sk_buff *skb, struct tcmsg *t)
1177 {
1178         struct tc_u_knode *n = fh;
1179         struct tc_u_hnode *ht_up, *ht_down;
1180         struct nlattr *nest;
1181
1182         if (n == NULL)
1183                 return skb->len;
1184
1185         t->tcm_handle = n->handle;
1186
1187         nest = nla_nest_start(skb, TCA_OPTIONS);
1188         if (nest == NULL)
1189                 goto nla_put_failure;
1190
1191         if (TC_U32_KEY(n->handle) == 0) {
1192                 struct tc_u_hnode *ht = fh;
1193                 u32 divisor = ht->divisor + 1;
1194
1195                 if (nla_put_u32(skb, TCA_U32_DIVISOR, divisor))
1196                         goto nla_put_failure;
1197         } else {
1198 #ifdef CONFIG_CLS_U32_PERF
1199                 struct tc_u32_pcnt *gpf;
1200                 int cpu;
1201 #endif
1202
1203                 if (nla_put(skb, TCA_U32_SEL,
1204                             sizeof(n->sel) + n->sel.nkeys*sizeof(struct tc_u32_key),
1205                             &n->sel))
1206                         goto nla_put_failure;
1207
1208                 ht_up = rtnl_dereference(n->ht_up);
1209                 if (ht_up) {
1210                         u32 htid = n->handle & 0xFFFFF000;
1211                         if (nla_put_u32(skb, TCA_U32_HASH, htid))
1212                                 goto nla_put_failure;
1213                 }
1214                 if (n->res.classid &&
1215                     nla_put_u32(skb, TCA_U32_CLASSID, n->res.classid))
1216                         goto nla_put_failure;
1217
1218                 ht_down = rtnl_dereference(n->ht_down);
1219                 if (ht_down &&
1220                     nla_put_u32(skb, TCA_U32_LINK, ht_down->handle))
1221                         goto nla_put_failure;
1222
1223                 if (n->flags && nla_put_u32(skb, TCA_U32_FLAGS, n->flags))
1224                         goto nla_put_failure;
1225
1226 #ifdef CONFIG_CLS_U32_MARK
1227                 if ((n->val || n->mask)) {
1228                         struct tc_u32_mark mark = {.val = n->val,
1229                                                    .mask = n->mask,
1230                                                    .success = 0};
1231                         int cpum;
1232
1233                         for_each_possible_cpu(cpum) {
1234                                 __u32 cnt = *per_cpu_ptr(n->pcpu_success, cpum);
1235
1236                                 mark.success += cnt;
1237                         }
1238
1239                         if (nla_put(skb, TCA_U32_MARK, sizeof(mark), &mark))
1240                                 goto nla_put_failure;
1241                 }
1242 #endif
1243
1244                 if (tcf_exts_dump(skb, &n->exts) < 0)
1245                         goto nla_put_failure;
1246
1247 #ifdef CONFIG_NET_CLS_IND
1248                 if (n->ifindex) {
1249                         struct net_device *dev;
1250                         dev = __dev_get_by_index(net, n->ifindex);
1251                         if (dev && nla_put_string(skb, TCA_U32_INDEV, dev->name))
1252                                 goto nla_put_failure;
1253                 }
1254 #endif
1255 #ifdef CONFIG_CLS_U32_PERF
1256                 gpf = kzalloc(sizeof(struct tc_u32_pcnt) +
1257                               n->sel.nkeys * sizeof(u64),
1258                               GFP_KERNEL);
1259                 if (!gpf)
1260                         goto nla_put_failure;
1261
1262                 for_each_possible_cpu(cpu) {
1263                         int i;
1264                         struct tc_u32_pcnt *pf = per_cpu_ptr(n->pf, cpu);
1265
1266                         gpf->rcnt += pf->rcnt;
1267                         gpf->rhit += pf->rhit;
1268                         for (i = 0; i < n->sel.nkeys; i++)
1269                                 gpf->kcnts[i] += pf->kcnts[i];
1270                 }
1271
1272                 if (nla_put_64bit(skb, TCA_U32_PCNT,
1273                                   sizeof(struct tc_u32_pcnt) +
1274                                   n->sel.nkeys * sizeof(u64),
1275                                   gpf, TCA_U32_PAD)) {
1276                         kfree(gpf);
1277                         goto nla_put_failure;
1278                 }
1279                 kfree(gpf);
1280 #endif
1281         }
1282
1283         nla_nest_end(skb, nest);
1284
1285         if (TC_U32_KEY(n->handle))
1286                 if (tcf_exts_dump_stats(skb, &n->exts) < 0)
1287                         goto nla_put_failure;
1288         return skb->len;
1289
1290 nla_put_failure:
1291         nla_nest_cancel(skb, nest);
1292         return -1;
1293 }
1294
1295 static struct tcf_proto_ops cls_u32_ops __read_mostly = {
1296         .kind           =       "u32",
1297         .classify       =       u32_classify,
1298         .init           =       u32_init,
1299         .destroy        =       u32_destroy,
1300         .get            =       u32_get,
1301         .change         =       u32_change,
1302         .delete         =       u32_delete,
1303         .walk           =       u32_walk,
1304         .dump           =       u32_dump,
1305         .bind_class     =       u32_bind_class,
1306         .owner          =       THIS_MODULE,
1307 };
1308
1309 static int __init init_u32(void)
1310 {
1311         int i, ret;
1312
1313         pr_info("u32 classifier\n");
1314 #ifdef CONFIG_CLS_U32_PERF
1315         pr_info("    Performance counters on\n");
1316 #endif
1317 #ifdef CONFIG_NET_CLS_IND
1318         pr_info("    input device check on\n");
1319 #endif
1320 #ifdef CONFIG_NET_CLS_ACT
1321         pr_info("    Actions configured\n");
1322 #endif
1323         tc_u_common_hash = kvmalloc_array(U32_HASH_SIZE,
1324                                           sizeof(struct hlist_head),
1325                                           GFP_KERNEL);
1326         if (!tc_u_common_hash)
1327                 return -ENOMEM;
1328
1329         for (i = 0; i < U32_HASH_SIZE; i++)
1330                 INIT_HLIST_HEAD(&tc_u_common_hash[i]);
1331
1332         ret = register_tcf_proto_ops(&cls_u32_ops);
1333         if (ret)
1334                 kvfree(tc_u_common_hash);
1335         return ret;
1336 }
1337
1338 static void __exit exit_u32(void)
1339 {
1340         unregister_tcf_proto_ops(&cls_u32_ops);
1341         kvfree(tc_u_common_hash);
1342 }
1343
1344 module_init(init_u32)
1345 module_exit(exit_u32)
1346 MODULE_LICENSE("GPL");