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
  50 struct tc_u_knode {
  51         struct tc_u_knode __rcu *next;
  52         u32                     handle;
  53         struct tc_u_hnode __rcu *ht_up;
  54         struct tcf_exts         exts;
  55 #ifdef CONFIG_NET_CLS_IND
  56         int                     ifindex;
  57 #endif
  58         u8                      fshift;
  59         struct tcf_result       res;
  60         struct tc_u_hnode __rcu *ht_down;
  61 #ifdef CONFIG_CLS_U32_PERF
  62         struct tc_u32_pcnt __percpu *pf;
  63 #endif
  64         u32                     flags;
  65 #ifdef CONFIG_CLS_U32_MARK
  66         u32                     val;
  67         u32                     mask;
  68         u32 __percpu            *pcpu_success;
  69 #endif
  70         struct tcf_proto        *tp;
  71         union {
  72                 struct work_struct      work;
  73                 struct rcu_head         rcu;
  74         };
  75         /* The 'sel' field MUST be the last field in structure to allow for
  76          * tc_u32_keys allocated at end of structure.
  77          */
  78         struct tc_u32_sel       sel;
  79 };
  80
  81 struct tc_u_hnode {
  82         struct tc_u_hnode __rcu *next;
  83         u32                     handle;
  84         u32                     prio;
  85         struct tc_u_common      *tp_c;
  86         int                     refcnt;
  87         unsigned int            divisor;
  88         struct rcu_head         rcu;
  89         /* The 'ht' field MUST be the last field in structure to allow for
  90          * more entries allocated at end of structure.
  91          */
  92         struct tc_u_knode __rcu *ht[1];
  93 };
  94
  95 struct tc_u_common {
  96         struct tc_u_hnode __rcu *hlist;
  97         struct Qdisc            *q;
  98         int                     refcnt;
  99         u32                     hgenerator;
 100         struct hlist_node       hnode;
 101         struct rcu_head         rcu;
 102 };
 103
 104 static inline unsigned int u32_hash_fold(__be32 key,
 105                                          const struct tc_u32_sel *sel,
 106                                          u8 fshift)
 107 {
 108         unsigned int h = ntohl(key & sel->hmask) >> fshift;
 109
 110         return h;
 111 }
 112
 113 static int u32_classify(struct sk_buff *skb, const struct tcf_proto *tp,
 114                         struct tcf_result *res)
 115 {
 116         struct {
 117                 struct tc_u_knode *knode;
 118                 unsigned int      off;
 119         } stack[TC_U32_MAXDEPTH];
 120
 121         struct tc_u_hnode *ht = rcu_dereference_bh(tp->root);
 122         unsigned int off = skb_network_offset(skb);
 123         struct tc_u_knode *n;
 124         int sdepth = 0;
 125         int off2 = 0;
 126         int sel = 0;
 127 #ifdef CONFIG_CLS_U32_PERF
 128         int j;
 129 #endif
 130         int i, r;
 131
 132 next_ht:
 133         n = rcu_dereference_bh(ht->ht[sel]);
 134
 135 next_knode:
 136         if (n) {
 137                 struct tc_u32_key *key = n->sel.keys;
 138
 139 #ifdef CONFIG_CLS_U32_PERF
 140                 __this_cpu_inc(n->pf->rcnt);
 141                 j = 0;
 142 #endif
 143
 144                 if (tc_skip_sw(n->flags)) {
 145                         n = rcu_dereference_bh(n->next);
 146                         goto next_knode;
 147                 }
 148
 149 #ifdef CONFIG_CLS_U32_MARK
 150                 if ((skb->mark & n->mask) != n->val) {
 151                         n = rcu_dereference_bh(n->next);
 152                         goto next_knode;
 153                 } else {
 154                         __this_cpu_inc(*n->pcpu_success);
 155                 }
 156 #endif
 157
 158                 for (i = n->sel.nkeys; i > 0; i--, key++) {
 159                         int toff = off + key->off + (off2 & key->offmask);
 160                         __be32 *data, hdata;
 161
 162                         if (skb_headroom(skb) + toff > INT_MAX)
 163                                 goto out;
 164
 165                         data = skb_header_pointer(skb, toff, 4, &hdata);
 166                         if (!data)
 167                                 goto out;
 168                         if ((*data ^ key->val) & key->mask) {
 169                                 n = rcu_dereference_bh(n->next);
 170                                 goto next_knode;
 171                         }
 172 #ifdef CONFIG_CLS_U32_PERF
 173                         __this_cpu_inc(n->pf->kcnts[j]);
 174                         j++;
 175 #endif
 176                 }
 177
 178                 ht = rcu_dereference_bh(n->ht_down);
 179                 if (!ht) {
 180 check_terminal:
 181                         if (n->sel.flags & TC_U32_TERMINAL) {
 182
 183                                 *res = n->res;
 184 #ifdef CONFIG_NET_CLS_IND
 185                                 if (!tcf_match_indev(skb, n->ifindex)) {
 186                                         n = rcu_dereference_bh(n->next);
 187                                         goto next_knode;
 188                                 }
 189 #endif
 190 #ifdef CONFIG_CLS_U32_PERF
 191                                 __this_cpu_inc(n->pf->rhit);
 192 #endif
 193                                 r = tcf_exts_exec(skb, &n->exts, res);
 194                                 if (r < 0) {
 195                                         n = rcu_dereference_bh(n->next);
 196                                         goto next_knode;
 197                                 }
 198
 199                                 return r;
 200                         }
 201                         n = rcu_dereference_bh(n->next);
 202                         goto next_knode;
 203                 }
 204
 205                 /* PUSH */
 206                 if (sdepth >= TC_U32_MAXDEPTH)
 207                         goto deadloop;
 208                 stack[sdepth].knode = n;
 209                 stack[sdepth].off = off;
 210                 sdepth++;
 211
 212                 ht = rcu_dereference_bh(n->ht_down);
 213                 sel = 0;
 214                 if (ht->divisor) {
 215                         __be32 *data, hdata;
 216
 217                         data = skb_header_pointer(skb, off + n->sel.hoff, 4,
 218                                                   &hdata);
 219                         if (!data)
 220                                 goto out;
 221                         sel = ht->divisor & u32_hash_fold(*data, &n->sel,
 222                                                           n->fshift);
 223                 }
 224                 if (!(n->sel.flags & (TC_U32_VAROFFSET | TC_U32_OFFSET | TC_U32_EAT)))
 225                         goto next_ht;
 226
 227                 if (n->sel.flags & (TC_U32_OFFSET | TC_U32_VAROFFSET)) {
 228                         off2 = n->sel.off + 3;
 229                         if (n->sel.flags & TC_U32_VAROFFSET) {
 230                                 __be16 *data, hdata;
 231
 232                                 data = skb_header_pointer(skb,
 233                                                           off + n->sel.offoff,
 234                                                           2, &hdata);
 235                                 if (!data)
 236                                         goto out;
 237                                 off2 += ntohs(n->sel.offmask & *data) >>
 238                                         n->sel.offshift;
 239                         }
 240                         off2 &= ~3;
 241                 }
 242                 if (n->sel.flags & TC_U32_EAT) {
 243                         off += off2;
 244                         off2 = 0;
 245                 }
 246
 247                 if (off < skb->len)
 248                         goto next_ht;
 249         }
 250
 251         /* POP */
 252         if (sdepth--) {
 253                 n = stack[sdepth].knode;
 254                 ht = rcu_dereference_bh(n->ht_up);
 255                 off = stack[sdepth].off;
 256                 goto check_terminal;
 257         }
 258 out:
 259         return -1;
 260
 261 deadloop:
 262         net_warn_ratelimited("cls_u32: dead loop\n");
 263         return -1;
 264 }
 265
 266 static struct tc_u_hnode *u32_lookup_ht(struct tc_u_common *tp_c, u32 handle)
 267 {
 268         struct tc_u_hnode *ht;
 269
 270         for (ht = rtnl_dereference(tp_c->hlist);
 271              ht;
 272              ht = rtnl_dereference(ht->next))
 273                 if (ht->handle == handle)
 274                         break;
 275
 276         return ht;
 277 }
 278
 279 static struct tc_u_knode *u32_lookup_key(struct tc_u_hnode *ht, u32 handle)
 280 {
 281         unsigned int sel;
 282         struct tc_u_knode *n = NULL;
 283
 284         sel = TC_U32_HASH(handle);
 285         if (sel > ht->divisor)
 286                 goto out;
 287
 288         for (n = rtnl_dereference(ht->ht[sel]);
 289              n;
 290              n = rtnl_dereference(n->next))
 291                 if (n->handle == handle)
 292                         break;
 293 out:
 294         return n;
 295 }
 296
 297
 298 static void *u32_get(struct tcf_proto *tp, u32 handle)
 299 {
 300         struct tc_u_hnode *ht;
 301         struct tc_u_common *tp_c = tp->data;
 302
 303         if (TC_U32_HTID(handle) == TC_U32_ROOT)
 304                 ht = rtnl_dereference(tp->root);
 305         else
 306                 ht = u32_lookup_ht(tp_c, TC_U32_HTID(handle));
 307
 308         if (!ht)
 309                 return NULL;
 310
 311         if (TC_U32_KEY(handle) == 0)
 312                 return ht;
 313
 314         return u32_lookup_key(ht, handle);
 315 }
 316
 317 static u32 gen_new_htid(struct tc_u_common *tp_c)
 318 {
 319         int i = 0x800;
 320
 321         /* hgenerator only used inside rtnl lock it is safe to increment
 322          * without read _copy_ update semantics
 323          */
 324         do {
 325                 if (++tp_c->hgenerator == 0x7FF)
 326                         tp_c->hgenerator = 1;
 327         } while (--i > 0 && u32_lookup_ht(tp_c, (tp_c->hgenerator|0x800)<<20));
 328
 329         return i > 0 ? (tp_c->hgenerator|0x800)<<20 : 0;
 330 }
 331
 332 static struct hlist_head *tc_u_common_hash;
 333
 334 #define U32_HASH_SHIFT 10
 335 #define U32_HASH_SIZE (1 << U32_HASH_SHIFT)
 336
 337 static unsigned int tc_u_hash(const struct tcf_proto *tp)
 338 {
 339         struct net_device *dev = tp->q->dev_queue->dev;
 340         u32 qhandle = tp->q->handle;
 341         int ifindex = dev->ifindex;
 342
 343         return hash_64((u64)ifindex << 32 | qhandle, U32_HASH_SHIFT);
 344 }
 345
 346 static struct tc_u_common *tc_u_common_find(const struct tcf_proto *tp)
 347 {
 348         struct tc_u_common *tc;
 349         unsigned int h;
 350
 351         h = tc_u_hash(tp);
 352         hlist_for_each_entry(tc, &tc_u_common_hash[h], hnode) {
 353                 if (tc->q == tp->q)
 354                         return tc;
 355         }
 356         return NULL;
 357 }
 358
 359 static int u32_init(struct tcf_proto *tp)
 360 {
 361         struct tc_u_hnode *root_ht;
 362         struct tc_u_common *tp_c;
 363         unsigned int h;
 364
 365         tp_c = tc_u_common_find(tp);
 366
 367         root_ht = kzalloc(sizeof(*root_ht), GFP_KERNEL);
 368         if (root_ht == NULL)
 369                 return -ENOBUFS;
 370
 371         root_ht->refcnt++;
 372         root_ht->handle = tp_c ? gen_new_htid(tp_c) : 0x80000000;
 373         root_ht->prio = tp->prio;
 374
 375         if (tp_c == NULL) {
 376                 tp_c = kzalloc(sizeof(*tp_c), GFP_KERNEL);
 377                 if (tp_c == NULL) {
 378                         kfree(root_ht);
 379                         return -ENOBUFS;
 380                 }
 381                 tp_c->q = tp->q;
 382                 INIT_HLIST_NODE(&tp_c->hnode);
 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         struct tc_u_hnode *ht = rtnl_dereference(n->ht_down);
 402
 403         tcf_exts_destroy(&n->exts);
 404         tcf_exts_put_net(&n->exts);
 405         if (ht && --ht->refcnt == 0)
 406                 kfree(ht);
 407 #ifdef CONFIG_CLS_U32_PERF
 408         if (free_pf)
 409                 free_percpu(n->pf);
 410 #endif
 411 #ifdef CONFIG_CLS_U32_MARK
 412         if (free_pf)
 413                 free_percpu(n->pcpu_success);
 414 #endif
 415         kfree(n);
 416         return 0;
 417 }
 418
 419 /* u32_delete_key_rcu should be called when free'ing a copied
 420  * version of a tc_u_knode obtained from u32_init_knode(). When
 421  * copies are obtained from u32_init_knode() the statistics are
 422  * shared between the old and new copies to allow readers to
 423  * continue to update the statistics during the copy. To support
 424  * this the u32_delete_key_rcu variant does not free the percpu
 425  * statistics.
 426  */
 427 static void u32_delete_key_work(struct work_struct *work)
 428 {
 429         struct tc_u_knode *key = container_of(work, struct tc_u_knode, work);
 430
 431         rtnl_lock();
 432         u32_destroy_key(key->tp, key, false);
 433         rtnl_unlock();
 434 }
 435
 436 static void u32_delete_key_rcu(struct rcu_head *rcu)
 437 {
 438         struct tc_u_knode *key = container_of(rcu, struct tc_u_knode, rcu);
 439
 440         INIT_WORK(&key->work, u32_delete_key_work);
 441         tcf_queue_work(&key->work);
 442 }
 443
 444 /* u32_delete_key_freepf_rcu is the rcu callback variant
 445  * that free's the entire structure including the statistics
 446  * percpu variables. Only use this if the key is not a copy
 447  * returned by u32_init_knode(). See u32_delete_key_rcu()
 448  * for the variant that should be used with keys return from
 449  * u32_init_knode()
 450  */
 451 static void u32_delete_key_freepf_work(struct work_struct *work)
 452 {
 453         struct tc_u_knode *key = container_of(work, struct tc_u_knode, work);
 454
 455         rtnl_lock();
 456         u32_destroy_key(key->tp, key, true);
 457         rtnl_unlock();
 458 }
 459
 460 static void u32_delete_key_freepf_rcu(struct rcu_head *rcu)
 461 {
 462         struct tc_u_knode *key = container_of(rcu, struct tc_u_knode, rcu);
 463
 464         INIT_WORK(&key->work, u32_delete_key_freepf_work);
 465         tcf_queue_work(&key->work);
 466 }
 467
 468 static int u32_delete_key(struct tcf_proto *tp, struct tc_u_knode *key)
 469 {
 470         struct tc_u_knode __rcu **kp;
 471         struct tc_u_knode *pkp;
 472         struct tc_u_hnode *ht = rtnl_dereference(key->ht_up);
 473
 474         if (ht) {
 475                 kp = &ht->ht[TC_U32_HASH(key->handle)];
 476                 for (pkp = rtnl_dereference(*kp); pkp;
 477                      kp = &pkp->next, pkp = rtnl_dereference(*kp)) {
 478                         if (pkp == key) {
 479                                 RCU_INIT_POINTER(*kp, key->next);
 480
 481                                 tcf_unbind_filter(tp, &key->res);
 482                                 tcf_exts_get_net(&key->exts);
 483                                 call_rcu(&key->rcu, u32_delete_key_freepf_rcu);
 484                                 return 0;
 485                         }
 486                 }
 487         }
 488         WARN_ON(1);
 489         return 0;
 490 }
 491
 492 static void u32_remove_hw_knode(struct tcf_proto *tp, u32 handle)
 493 {
 494         struct net_device *dev = tp->q->dev_queue->dev;
 495         struct tc_cls_u32_offload cls_u32 = {};
 496
 497         if (!tc_should_offload(dev, 0))
 498                 return;
 499
 500         tc_cls_common_offload_init(&cls_u32.common, tp);
 501         cls_u32.command = TC_CLSU32_DELETE_KNODE;
 502         cls_u32.knode.handle = handle;
 503
 504         dev->netdev_ops->ndo_setup_tc(dev, TC_SETUP_CLSU32, &cls_u32);
 505 }
 506
 507 static int u32_replace_hw_hnode(struct tcf_proto *tp, struct tc_u_hnode *h,
 508                                 u32 flags)
 509 {
 510         struct net_device *dev = tp->q->dev_queue->dev;
 511         struct tc_cls_u32_offload cls_u32 = {};
 512         int err;
 513
 514         if (!tc_should_offload(dev, flags))
 515                 return tc_skip_sw(flags) ? -EINVAL : 0;
 516
 517         tc_cls_common_offload_init(&cls_u32.common, tp);
 518         cls_u32.command = TC_CLSU32_NEW_HNODE;
 519         cls_u32.hnode.divisor = h->divisor;
 520         cls_u32.hnode.handle = h->handle;
 521         cls_u32.hnode.prio = h->prio;
 522
 523         err = dev->netdev_ops->ndo_setup_tc(dev, TC_SETUP_CLSU32, &cls_u32);
 524         if (tc_skip_sw(flags))
 525                 return err;
 526
 527         return 0;
 528 }
 529
 530 static void u32_clear_hw_hnode(struct tcf_proto *tp, struct tc_u_hnode *h)
 531 {
 532         struct net_device *dev = tp->q->dev_queue->dev;
 533         struct tc_cls_u32_offload cls_u32 = {};
 534
 535         if (!tc_should_offload(dev, 0))
 536                 return;
 537
 538         tc_cls_common_offload_init(&cls_u32.common, tp);
 539         cls_u32.command = TC_CLSU32_DELETE_HNODE;
 540         cls_u32.hnode.divisor = h->divisor;
 541         cls_u32.hnode.handle = h->handle;
 542         cls_u32.hnode.prio = h->prio;
 543
 544         dev->netdev_ops->ndo_setup_tc(dev, TC_SETUP_CLSU32, &cls_u32);
 545 }
 546
 547 static int u32_replace_hw_knode(struct tcf_proto *tp, struct tc_u_knode *n,
 548                                 u32 flags)
 549 {
 550         struct net_device *dev = tp->q->dev_queue->dev;
 551         struct tc_cls_u32_offload cls_u32 = {};
 552         int err;
 553
 554         if (!tc_should_offload(dev, flags))
 555                 return tc_skip_sw(flags) ? -EINVAL : 0;
 556
 557         tc_cls_common_offload_init(&cls_u32.common, tp);
 558         cls_u32.command = TC_CLSU32_REPLACE_KNODE;
 559         cls_u32.knode.handle = n->handle;
 560         cls_u32.knode.fshift = n->fshift;
 561 #ifdef CONFIG_CLS_U32_MARK
 562         cls_u32.knode.val = n->val;
 563         cls_u32.knode.mask = n->mask;
 564 #else
 565         cls_u32.knode.val = 0;
 566         cls_u32.knode.mask = 0;
 567 #endif
 568         cls_u32.knode.sel = &n->sel;
 569         cls_u32.knode.exts = &n->exts;
 570         if (n->ht_down)
 571                 cls_u32.knode.link_handle = n->ht_down->handle;
 572
 573         err = dev->netdev_ops->ndo_setup_tc(dev, TC_SETUP_CLSU32, &cls_u32);
 574
 575         if (!err)
 576                 n->flags |= TCA_CLS_FLAGS_IN_HW;
 577
 578         if (tc_skip_sw(flags))
 579                 return err;
 580
 581         return 0;
 582 }
 583
 584 static void u32_clear_hnode(struct tcf_proto *tp, struct tc_u_hnode *ht)
 585 {
 586         struct tc_u_knode *n;
 587         unsigned int h;
 588
 589         for (h = 0; h <= ht->divisor; h++) {
 590                 while ((n = rtnl_dereference(ht->ht[h])) != NULL) {
 591                         RCU_INIT_POINTER(ht->ht[h],
 592                                          rtnl_dereference(n->next));
 593                         tcf_unbind_filter(tp, &n->res);
 594                         u32_remove_hw_knode(tp, 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                         RCU_INIT_POINTER(*hn, ht->next);
 620                         kfree_rcu(ht, rcu);
 621                         return 0;
 622                 }
 623         }
 624
 625         return -ENOENT;
 626 }
 627
 628 static bool ht_empty(struct tc_u_hnode *ht)
 629 {
 630         unsigned int h;
 631
 632         for (h = 0; h <= ht->divisor; h++)
 633                 if (rcu_access_pointer(ht->ht[h]))
 634                         return false;
 635
 636         return true;
 637 }
 638
 639 static void u32_destroy(struct tcf_proto *tp)
 640 {
 641         struct tc_u_common *tp_c = tp->data;
 642         struct tc_u_hnode *root_ht = rtnl_dereference(tp->root);
 643
 644         WARN_ON(root_ht == NULL);
 645
 646         if (root_ht && --root_ht->refcnt == 0)
 647                 u32_destroy_hnode(tp, root_ht);
 648
 649         if (--tp_c->refcnt == 0) {
 650                 struct tc_u_hnode *ht;
 651
 652                 hlist_del(&tp_c->hnode);
 653
 654                 while ((ht = rtnl_dereference(tp_c->hlist)) != NULL) {
 655                         u32_clear_hnode(tp, ht);
 656                         RCU_INIT_POINTER(tp_c->hlist, ht->next);
 657
 658                         /* u32_destroy_key() will later free ht for us, if it's
 659                          * still referenced by some knode
 660                          */
 661                         if (--ht->refcnt == 0)
 662                                 kfree_rcu(ht, rcu);
 663                 }
 664
 665                 kfree(tp_c);
 666         }
 667
 668         tp->data = NULL;
 669 }
 670
 671 static int u32_delete(struct tcf_proto *tp, void *arg, bool *last)
 672 {
 673         struct tc_u_hnode *ht = arg;
 674         struct tc_u_hnode *root_ht = rtnl_dereference(tp->root);
 675         struct tc_u_common *tp_c = tp->data;
 676         int ret = 0;
 677
 678         if (ht == NULL)
 679                 goto out;
 680
 681         if (TC_U32_KEY(ht->handle)) {
 682                 u32_remove_hw_knode(tp, ht->handle);
 683                 ret = u32_delete_key(tp, (struct tc_u_knode *)ht);
 684                 goto out;
 685         }
 686
 687         if (root_ht == ht)
 688                 return -EINVAL;
 689
 690         if (ht->refcnt == 1) {
 691                 ht->refcnt--;
 692                 u32_destroy_hnode(tp, ht);
 693         } else {
 694                 return -EBUSY;
 695         }
 696
 697 out:
 698         *last = true;
 699         if (root_ht) {
 700                 if (root_ht->refcnt > 1) {
 701                         *last = false;
 702                         goto ret;
 703                 }
 704                 if (root_ht->refcnt == 1) {
 705                         if (!ht_empty(root_ht)) {
 706                                 *last = false;
 707                                 goto ret;
 708                         }
 709                 }
 710         }
 711
 712         if (tp_c->refcnt > 1) {
 713                 *last = false;
 714                 goto ret;
 715         }
 716
 717         if (tp_c->refcnt == 1) {
 718                 struct tc_u_hnode *ht;
 719
 720                 for (ht = rtnl_dereference(tp_c->hlist);
 721                      ht;
 722                      ht = rtnl_dereference(ht->next))
 723                         if (!ht_empty(ht)) {
 724                                 *last = false;
 725                                 break;
 726                         }
 727         }
 728
 729 ret:
 730         return ret;
 731 }
 732
 733 #define NR_U32_NODE (1<<12)
 734 static u32 gen_new_kid(struct tc_u_hnode *ht, u32 handle)
 735 {
 736         struct tc_u_knode *n;
 737         unsigned long i;
 738         unsigned long *bitmap = kzalloc(BITS_TO_LONGS(NR_U32_NODE) * sizeof(unsigned long),
 739                                         GFP_KERNEL);
 740         if (!bitmap)
 741                 return handle | 0xFFF;
 742
 743         for (n = rtnl_dereference(ht->ht[TC_U32_HASH(handle)]);
 744              n;
 745              n = rtnl_dereference(n->next))
 746                 set_bit(TC_U32_NODE(n->handle), bitmap);
 747
 748         i = find_next_zero_bit(bitmap, NR_U32_NODE, 0x800);
 749         if (i >= NR_U32_NODE)
 750                 i = find_next_zero_bit(bitmap, NR_U32_NODE, 1);
 751
 752         kfree(bitmap);
 753         return handle | (i >= NR_U32_NODE ? 0xFFF : i);
 754 }
 755
 756 static const struct nla_policy u32_policy[TCA_U32_MAX + 1] = {
 757         [TCA_U32_CLASSID]       = { .type = NLA_U32 },
 758         [TCA_U32_HASH]          = { .type = NLA_U32 },
 759         [TCA_U32_LINK]          = { .type = NLA_U32 },
 760         [TCA_U32_DIVISOR]       = { .type = NLA_U32 },
 761         [TCA_U32_SEL]           = { .len = sizeof(struct tc_u32_sel) },
 762         [TCA_U32_INDEV]         = { .type = NLA_STRING, .len = IFNAMSIZ },
 763         [TCA_U32_MARK]          = { .len = sizeof(struct tc_u32_mark) },
 764         [TCA_U32_FLAGS]         = { .type = NLA_U32 },
 765 };
 766
 767 static int u32_set_parms(struct net *net, struct tcf_proto *tp,
 768                          unsigned long base, struct tc_u_hnode *ht,
 769                          struct tc_u_knode *n, struct nlattr **tb,
 770                          struct nlattr *est, bool ovr)
 771 {
 772         int err;
 773
 774         err = tcf_exts_validate(net, tp, tb, est, &n->exts, ovr);
 775         if (err < 0)
 776                 return err;
 777
 778         if (tb[TCA_U32_LINK]) {
 779                 u32 handle = nla_get_u32(tb[TCA_U32_LINK]);
 780                 struct tc_u_hnode *ht_down = NULL, *ht_old;
 781
 782                 if (TC_U32_KEY(handle))
 783                         return -EINVAL;
 784
 785                 if (handle) {
 786                         ht_down = u32_lookup_ht(ht->tp_c, handle);
 787
 788                         if (ht_down == NULL)
 789                                 return -EINVAL;
 790                         ht_down->refcnt++;
 791                 }
 792
 793                 ht_old = rtnl_dereference(n->ht_down);
 794                 rcu_assign_pointer(n->ht_down, ht_down);
 795
 796                 if (ht_old)
 797                         ht_old->refcnt--;
 798         }
 799         if (tb[TCA_U32_CLASSID]) {
 800                 n->res.classid = nla_get_u32(tb[TCA_U32_CLASSID]);
 801                 tcf_bind_filter(tp, &n->res, base);
 802         }
 803
 804 #ifdef CONFIG_NET_CLS_IND
 805         if (tb[TCA_U32_INDEV]) {
 806                 int ret;
 807                 ret = tcf_change_indev(net, tb[TCA_U32_INDEV]);
 808                 if (ret < 0)
 809                         return -EINVAL;
 810                 n->ifindex = ret;
 811         }
 812 #endif
 813         return 0;
 814 }
 815
 816 static void u32_replace_knode(struct tcf_proto *tp, struct tc_u_common *tp_c,
 817                               struct tc_u_knode *n)
 818 {
 819         struct tc_u_knode __rcu **ins;
 820         struct tc_u_knode *pins;
 821         struct tc_u_hnode *ht;
 822
 823         if (TC_U32_HTID(n->handle) == TC_U32_ROOT)
 824                 ht = rtnl_dereference(tp->root);
 825         else
 826                 ht = u32_lookup_ht(tp_c, TC_U32_HTID(n->handle));
 827
 828         ins = &ht->ht[TC_U32_HASH(n->handle)];
 829
 830         /* The node must always exist for it to be replaced if this is not the
 831          * case then something went very wrong elsewhere.
 832          */
 833         for (pins = rtnl_dereference(*ins); ;
 834              ins = &pins->next, pins = rtnl_dereference(*ins))
 835                 if (pins->handle == n->handle)
 836                         break;
 837
 838         RCU_INIT_POINTER(n->next, pins->next);
 839         rcu_assign_pointer(*ins, n);
 840 }
 841
 842 static struct tc_u_knode *u32_init_knode(struct tcf_proto *tp,
 843                                          struct tc_u_knode *n)
 844 {
 845         struct tc_u_knode *new;
 846         struct tc_u32_sel *s = &n->sel;
 847
 848         new = kzalloc(sizeof(*n) + s->nkeys*sizeof(struct tc_u32_key),
 849                       GFP_KERNEL);
 850
 851         if (!new)
 852                 return NULL;
 853
 854         RCU_INIT_POINTER(new->next, n->next);
 855         new->handle = n->handle;
 856         RCU_INIT_POINTER(new->ht_up, n->ht_up);
 857
 858 #ifdef CONFIG_NET_CLS_IND
 859         new->ifindex = n->ifindex;
 860 #endif
 861         new->fshift = n->fshift;
 862         new->res = n->res;
 863         new->flags = n->flags;
 864         RCU_INIT_POINTER(new->ht_down, n->ht_down);
 865
 866         /* bump reference count as long as we hold pointer to structure */
 867         if (new->ht_down)
 868                 new->ht_down->refcnt++;
 869
 870 #ifdef CONFIG_CLS_U32_PERF
 871         /* Statistics may be incremented by readers during update
 872          * so we must keep them in tact. When the node is later destroyed
 873          * a special destroy call must be made to not free the pf memory.
 874          */
 875         new->pf = n->pf;
 876 #endif
 877
 878 #ifdef CONFIG_CLS_U32_MARK
 879         new->val = n->val;
 880         new->mask = n->mask;
 881         /* Similarly success statistics must be moved as pointers */
 882         new->pcpu_success = n->pcpu_success;
 883 #endif
 884         new->tp = tp;
 885         memcpy(&new->sel, s, sizeof(*s) + s->nkeys*sizeof(struct tc_u32_key));
 886
 887         if (tcf_exts_init(&new->exts, TCA_U32_ACT, TCA_U32_POLICE)) {
 888                 kfree(new);
 889                 return NULL;
 890         }
 891
 892         return new;
 893 }
 894
 895 static int u32_change(struct net *net, struct sk_buff *in_skb,
 896                       struct tcf_proto *tp, unsigned long base, u32 handle,
 897                       struct nlattr **tca, void **arg, bool ovr)
 898 {
 899         struct tc_u_common *tp_c = tp->data;
 900         struct tc_u_hnode *ht;
 901         struct tc_u_knode *n;
 902         struct tc_u32_sel *s;
 903         struct nlattr *opt = tca[TCA_OPTIONS];
 904         struct nlattr *tb[TCA_U32_MAX + 1];
 905         u32 htid, flags = 0;
 906         size_t sel_size;
 907         int err;
 908 #ifdef CONFIG_CLS_U32_PERF
 909         size_t size;
 910 #endif
 911
 912         if (opt == NULL)
 913                 return handle ? -EINVAL : 0;
 914
 915         err = nla_parse_nested(tb, TCA_U32_MAX, opt, u32_policy, NULL);
 916         if (err < 0)
 917                 return err;
 918
 919         if (tb[TCA_U32_FLAGS]) {
 920                 flags = nla_get_u32(tb[TCA_U32_FLAGS]);
 921                 if (!tc_flags_valid(flags))
 922                         return -EINVAL;
 923         }
 924
 925         n = *arg;
 926         if (n) {
 927                 struct tc_u_knode *new;
 928
 929                 if (TC_U32_KEY(n->handle) == 0)
 930                         return -EINVAL;
 931
 932                 if ((n->flags ^ flags) &
 933                     ~(TCA_CLS_FLAGS_IN_HW | TCA_CLS_FLAGS_NOT_IN_HW))
 934                         return -EINVAL;
 935
 936                 new = u32_init_knode(tp, n);
 937                 if (!new)
 938                         return -ENOMEM;
 939
 940                 err = u32_set_parms(net, tp, base,
 941                                     rtnl_dereference(n->ht_up), new, tb,
 942                                     tca[TCA_RATE], ovr);
 943
 944                 if (err) {
 945                         u32_destroy_key(tp, new, false);
 946                         return err;
 947                 }
 948
 949                 err = u32_replace_hw_knode(tp, new, flags);
 950                 if (err) {
 951                         u32_destroy_key(tp, new, false);
 952                         return err;
 953                 }
 954
 955                 if (!tc_in_hw(new->flags))
 956                         new->flags |= TCA_CLS_FLAGS_NOT_IN_HW;
 957
 958                 u32_replace_knode(tp, tp_c, new);
 959                 tcf_unbind_filter(tp, &n->res);
 960                 tcf_exts_get_net(&n->exts);
 961                 call_rcu(&n->rcu, u32_delete_key_rcu);
 962                 return 0;
 963         }
 964
 965         if (tb[TCA_U32_DIVISOR]) {
 966                 unsigned int divisor = nla_get_u32(tb[TCA_U32_DIVISOR]);
 967
 968                 if (--divisor > 0x100)
 969                         return -EINVAL;
 970                 if (TC_U32_KEY(handle))
 971                         return -EINVAL;
 972                 if (handle == 0) {
 973                         handle = gen_new_htid(tp->data);
 974                         if (handle == 0)
 975                                 return -ENOMEM;
 976                 }
 977                 ht = kzalloc(sizeof(*ht) + divisor*sizeof(void *), GFP_KERNEL);
 978                 if (ht == NULL)
 979                         return -ENOBUFS;
 980                 ht->tp_c = tp_c;
 981                 ht->refcnt = 1;
 982                 ht->divisor = divisor;
 983                 ht->handle = handle;
 984                 ht->prio = tp->prio;
 985
 986                 err = u32_replace_hw_hnode(tp, ht, flags);
 987                 if (err) {
 988                         kfree(ht);
 989                         return err;
 990                 }
 991
 992                 RCU_INIT_POINTER(ht->next, tp_c->hlist);
 993                 rcu_assign_pointer(tp_c->hlist, ht);
 994                 *arg = ht;
 995
 996                 return 0;
 997         }
 998
 999         if (tb[TCA_U32_HASH]) {
1000                 htid = nla_get_u32(tb[TCA_U32_HASH]);
1001                 if (TC_U32_HTID(htid) == TC_U32_ROOT) {
1002                         ht = rtnl_dereference(tp->root);
1003                         htid = ht->handle;
1004                 } else {
1005                         ht = u32_lookup_ht(tp->data, TC_U32_HTID(htid));
1006                         if (ht == NULL)
1007                                 return -EINVAL;
1008                 }
1009         } else {
1010                 ht = rtnl_dereference(tp->root);
1011                 htid = ht->handle;
1012         }
1013
1014         if (ht->divisor < TC_U32_HASH(htid))
1015                 return -EINVAL;
1016
1017         if (handle) {
1018                 if (TC_U32_HTID(handle) && TC_U32_HTID(handle^htid))
1019                         return -EINVAL;
1020                 handle = htid | TC_U32_NODE(handle);
1021         } else
1022                 handle = gen_new_kid(ht, htid);
1023
1024         if (tb[TCA_U32_SEL] == NULL)
1025                 return -EINVAL;
1026
1027         s = nla_data(tb[TCA_U32_SEL]);
1028         sel_size = sizeof(*s) + sizeof(*s->keys) * s->nkeys;
1029         if (nla_len(tb[TCA_U32_SEL]) < sel_size)
1030                 return -EINVAL;
1031
1032         n = kzalloc(offsetof(typeof(*n), sel) + sel_size, GFP_KERNEL);
1033         if (n == NULL)
1034                 return -ENOBUFS;
1035
1036 #ifdef CONFIG_CLS_U32_PERF
1037         size = sizeof(struct tc_u32_pcnt) + s->nkeys * sizeof(u64);
1038         n->pf = __alloc_percpu(size, __alignof__(struct tc_u32_pcnt));
1039         if (!n->pf) {
1040                 kfree(n);
1041                 return -ENOBUFS;
1042         }
1043 #endif
1044
1045         memcpy(&n->sel, s, sel_size);
1046         RCU_INIT_POINTER(n->ht_up, ht);
1047         n->handle = handle;
1048         n->fshift = s->hmask ? ffs(ntohl(s->hmask)) - 1 : 0;
1049         n->flags = flags;
1050         n->tp = tp;
1051
1052         err = tcf_exts_init(&n->exts, TCA_U32_ACT, TCA_U32_POLICE);
1053         if (err < 0)
1054                 goto errout;
1055
1056 #ifdef CONFIG_CLS_U32_MARK
1057         n->pcpu_success = alloc_percpu(u32);
1058         if (!n->pcpu_success) {
1059                 err = -ENOMEM;
1060                 goto errout;
1061         }
1062
1063         if (tb[TCA_U32_MARK]) {
1064                 struct tc_u32_mark *mark;
1065
1066                 mark = nla_data(tb[TCA_U32_MARK]);
1067                 n->val = mark->val;
1068                 n->mask = mark->mask;
1069         }
1070 #endif
1071
1072         err = u32_set_parms(net, tp, base, ht, n, tb, tca[TCA_RATE], ovr);
1073         if (err == 0) {
1074                 struct tc_u_knode __rcu **ins;
1075                 struct tc_u_knode *pins;
1076
1077                 err = u32_replace_hw_knode(tp, n, flags);
1078                 if (err)
1079                         goto errhw;
1080
1081                 if (!tc_in_hw(n->flags))
1082                         n->flags |= TCA_CLS_FLAGS_NOT_IN_HW;
1083
1084                 ins = &ht->ht[TC_U32_HASH(handle)];
1085                 for (pins = rtnl_dereference(*ins); pins;
1086                      ins = &pins->next, pins = rtnl_dereference(*ins))
1087                         if (TC_U32_NODE(handle) < TC_U32_NODE(pins->handle))
1088                                 break;
1089
1090                 RCU_INIT_POINTER(n->next, pins);
1091                 rcu_assign_pointer(*ins, n);
1092                 *arg = n;
1093                 return 0;
1094         }
1095
1096 errhw:
1097 #ifdef CONFIG_CLS_U32_MARK
1098         free_percpu(n->pcpu_success);
1099 #endif
1100
1101 errout:
1102         tcf_exts_destroy(&n->exts);
1103 #ifdef CONFIG_CLS_U32_PERF
1104         free_percpu(n->pf);
1105 #endif
1106         kfree(n);
1107         return err;
1108 }
1109
1110 static void u32_walk(struct tcf_proto *tp, struct tcf_walker *arg)
1111 {
1112         struct tc_u_common *tp_c = tp->data;
1113         struct tc_u_hnode *ht;
1114         struct tc_u_knode *n;
1115         unsigned int h;
1116
1117         if (arg->stop)
1118                 return;
1119
1120         for (ht = rtnl_dereference(tp_c->hlist);
1121              ht;
1122              ht = rtnl_dereference(ht->next)) {
1123                 if (ht->prio != tp->prio)
1124                         continue;
1125                 if (arg->count >= arg->skip) {
1126                         if (arg->fn(tp, ht, arg) < 0) {
1127                                 arg->stop = 1;
1128                                 return;
1129                         }
1130                 }
1131                 arg->count++;
1132                 for (h = 0; h <= ht->divisor; h++) {
1133                         for (n = rtnl_dereference(ht->ht[h]);
1134                              n;
1135                              n = rtnl_dereference(n->next)) {
1136                                 if (arg->count < arg->skip) {
1137                                         arg->count++;
1138                                         continue;
1139                                 }
1140                                 if (arg->fn(tp, n, arg) < 0) {
1141                                         arg->stop = 1;
1142                                         return;
1143                                 }
1144                                 arg->count++;
1145                         }
1146                 }
1147         }
1148 }
1149
1150 static void u32_bind_class(void *fh, u32 classid, unsigned long cl)
1151 {
1152         struct tc_u_knode *n = fh;
1153
1154         if (n && n->res.classid == classid)
1155                 n->res.class = cl;
1156 }
1157
1158 static int u32_dump(struct net *net, struct tcf_proto *tp, void *fh,
1159                     struct sk_buff *skb, struct tcmsg *t)
1160 {
1161         struct tc_u_knode *n = fh;
1162         struct tc_u_hnode *ht_up, *ht_down;
1163         struct nlattr *nest;
1164
1165         if (n == NULL)
1166                 return skb->len;
1167
1168         t->tcm_handle = n->handle;
1169
1170         nest = nla_nest_start(skb, TCA_OPTIONS);
1171         if (nest == NULL)
1172                 goto nla_put_failure;
1173
1174         if (TC_U32_KEY(n->handle) == 0) {
1175                 struct tc_u_hnode *ht = fh;
1176                 u32 divisor = ht->divisor + 1;
1177
1178                 if (nla_put_u32(skb, TCA_U32_DIVISOR, divisor))
1179                         goto nla_put_failure;
1180         } else {
1181 #ifdef CONFIG_CLS_U32_PERF
1182                 struct tc_u32_pcnt *gpf;
1183                 int cpu;
1184 #endif
1185
1186                 if (nla_put(skb, TCA_U32_SEL,
1187                             sizeof(n->sel) + n->sel.nkeys*sizeof(struct tc_u32_key),
1188                             &n->sel))
1189                         goto nla_put_failure;
1190
1191                 ht_up = rtnl_dereference(n->ht_up);
1192                 if (ht_up) {
1193                         u32 htid = n->handle & 0xFFFFF000;
1194                         if (nla_put_u32(skb, TCA_U32_HASH, htid))
1195                                 goto nla_put_failure;
1196                 }
1197                 if (n->res.classid &&
1198                     nla_put_u32(skb, TCA_U32_CLASSID, n->res.classid))
1199                         goto nla_put_failure;
1200
1201                 ht_down = rtnl_dereference(n->ht_down);
1202                 if (ht_down &&
1203                     nla_put_u32(skb, TCA_U32_LINK, ht_down->handle))
1204                         goto nla_put_failure;
1205
1206                 if (n->flags && nla_put_u32(skb, TCA_U32_FLAGS, n->flags))
1207                         goto nla_put_failure;
1208
1209 #ifdef CONFIG_CLS_U32_MARK
1210                 if ((n->val || n->mask)) {
1211                         struct tc_u32_mark mark = {.val = n->val,
1212                                                    .mask = n->mask,
1213                                                    .success = 0};
1214                         int cpum;
1215
1216                         for_each_possible_cpu(cpum) {
1217                                 __u32 cnt = *per_cpu_ptr(n->pcpu_success, cpum);
1218
1219                                 mark.success += cnt;
1220                         }
1221
1222                         if (nla_put(skb, TCA_U32_MARK, sizeof(mark), &mark))
1223                                 goto nla_put_failure;
1224                 }
1225 #endif
1226
1227                 if (tcf_exts_dump(skb, &n->exts) < 0)
1228                         goto nla_put_failure;
1229
1230 #ifdef CONFIG_NET_CLS_IND
1231                 if (n->ifindex) {
1232                         struct net_device *dev;
1233                         dev = __dev_get_by_index(net, n->ifindex);
1234                         if (dev && nla_put_string(skb, TCA_U32_INDEV, dev->name))
1235                                 goto nla_put_failure;
1236                 }
1237 #endif
1238 #ifdef CONFIG_CLS_U32_PERF
1239                 gpf = kzalloc(sizeof(struct tc_u32_pcnt) +
1240                               n->sel.nkeys * sizeof(u64),
1241                               GFP_KERNEL);
1242                 if (!gpf)
1243                         goto nla_put_failure;
1244
1245                 for_each_possible_cpu(cpu) {
1246                         int i;
1247                         struct tc_u32_pcnt *pf = per_cpu_ptr(n->pf, cpu);
1248
1249                         gpf->rcnt += pf->rcnt;
1250                         gpf->rhit += pf->rhit;
1251                         for (i = 0; i < n->sel.nkeys; i++)
1252                                 gpf->kcnts[i] += pf->kcnts[i];
1253                 }
1254
1255                 if (nla_put_64bit(skb, TCA_U32_PCNT,
1256                                   sizeof(struct tc_u32_pcnt) +
1257                                   n->sel.nkeys * sizeof(u64),
1258                                   gpf, TCA_U32_PAD)) {
1259                         kfree(gpf);
1260                         goto nla_put_failure;
1261                 }
1262                 kfree(gpf);
1263 #endif
1264         }
1265
1266         nla_nest_end(skb, nest);
1267
1268         if (TC_U32_KEY(n->handle))
1269                 if (tcf_exts_dump_stats(skb, &n->exts) < 0)
1270                         goto nla_put_failure;
1271         return skb->len;
1272
1273 nla_put_failure:
1274         nla_nest_cancel(skb, nest);
1275         return -1;
1276 }
1277
1278 static struct tcf_proto_ops cls_u32_ops __read_mostly = {
1279         .kind           =       "u32",
1280         .classify       =       u32_classify,
1281         .init           =       u32_init,
1282         .destroy        =       u32_destroy,
1283         .get            =       u32_get,
1284         .change         =       u32_change,
1285         .delete         =       u32_delete,
1286         .walk           =       u32_walk,
1287         .dump           =       u32_dump,
1288         .bind_class     =       u32_bind_class,
1289         .owner          =       THIS_MODULE,
1290 };
1291
1292 static int __init init_u32(void)
1293 {
1294         int i, ret;
1295
1296         pr_info("u32 classifier\n");
1297 #ifdef CONFIG_CLS_U32_PERF
1298         pr_info("    Performance counters on\n");
1299 #endif
1300 #ifdef CONFIG_NET_CLS_IND
1301         pr_info("    input device check on\n");
1302 #endif
1303 #ifdef CONFIG_NET_CLS_ACT
1304         pr_info("    Actions configured\n");
1305 #endif
1306         tc_u_common_hash = kvmalloc_array(U32_HASH_SIZE,
1307                                           sizeof(struct hlist_head),
1308                                           GFP_KERNEL);
1309         if (!tc_u_common_hash)
1310                 return -ENOMEM;
1311
1312         for (i = 0; i < U32_HASH_SIZE; i++)
1313                 INIT_HLIST_HEAD(&tc_u_common_hash[i]);
1314
1315         ret = register_tcf_proto_ops(&cls_u32_ops);
1316         if (ret)
1317                 kvfree(tc_u_common_hash);
1318         return ret;
1319 }
1320
1321 static void __exit exit_u32(void)
1322 {
1323         unregister_tcf_proto_ops(&cls_u32_ops);
1324         kvfree(tc_u_common_hash);
1325 }
1326
1327 module_init(init_u32)
1328 module_exit(exit_u32)
1329 MODULE_LICENSE("GPL");