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 <net/netlink.h>
  44 #include <net/act_api.h>
  45 #include <net/pkt_cls.h>
  46
  47 struct tc_u_knode {
  48         struct tc_u_knode __rcu *next;
  49         u32                     handle;
  50         struct tc_u_hnode __rcu *ht_up;
  51         struct tcf_exts         exts;
  52 #ifdef CONFIG_NET_CLS_IND
  53         int                     ifindex;
  54 #endif
  55         u8                      fshift;
  56         struct tcf_result       res;
  57         struct tc_u_hnode __rcu *ht_down;
  58 #ifdef CONFIG_CLS_U32_PERF
  59         struct tc_u32_pcnt __percpu *pf;
  60 #endif
  61 #ifdef CONFIG_CLS_U32_MARK
  62         u32                     val;
  63         u32                     mask;
  64         u32 __percpu            *pcpu_success;
  65 #endif
  66         struct tcf_proto        *tp;
  67         struct rcu_head         rcu;
  68         /* The 'sel' field MUST be the last field in structure to allow for
  69          * tc_u32_keys allocated at end of structure.
  70          */
  71         struct tc_u32_sel       sel;
  72 };
  73
  74 struct tc_u_hnode {
  75         struct tc_u_hnode __rcu *next;
  76         u32                     handle;
  77         u32                     prio;
  78         struct tc_u_common      *tp_c;
  79         int                     refcnt;
  80         unsigned int            divisor;
  81         struct tc_u_knode __rcu *ht[1];
  82         struct rcu_head         rcu;
  83 };
  84
  85 struct tc_u_common {
  86         struct tc_u_hnode __rcu *hlist;
  87         struct Qdisc            *q;
  88         int                     refcnt;
  89         u32                     hgenerator;
  90         struct rcu_head         rcu;
  91 };
  92
  93 static inline unsigned int u32_hash_fold(__be32 key,
  94                                          const struct tc_u32_sel *sel,
  95                                          u8 fshift)
  96 {
  97         unsigned int h = ntohl(key & sel->hmask) >> fshift;
  98
  99         return h;
 100 }
 101
 102 static int u32_classify(struct sk_buff *skb, const struct tcf_proto *tp, struct tcf_result *res)
 103 {
 104         struct {
 105                 struct tc_u_knode *knode;
 106                 unsigned int      off;
 107         } stack[TC_U32_MAXDEPTH];
 108
 109         struct tc_u_hnode *ht = rcu_dereference_bh(tp->root);
 110         unsigned int off = skb_network_offset(skb);
 111         struct tc_u_knode *n;
 112         int sdepth = 0;
 113         int off2 = 0;
 114         int sel = 0;
 115 #ifdef CONFIG_CLS_U32_PERF
 116         int j;
 117 #endif
 118         int i, r;
 119
 120 next_ht:
 121         n = rcu_dereference_bh(ht->ht[sel]);
 122
 123 next_knode:
 124         if (n) {
 125                 struct tc_u32_key *key = n->sel.keys;
 126
 127 #ifdef CONFIG_CLS_U32_PERF
 128                 __this_cpu_inc(n->pf->rcnt);
 129                 j = 0;
 130 #endif
 131
 132 #ifdef CONFIG_CLS_U32_MARK
 133                 if ((skb->mark & n->mask) != n->val) {
 134                         n = rcu_dereference_bh(n->next);
 135                         goto next_knode;
 136                 } else {
 137                         __this_cpu_inc(*n->pcpu_success);
 138                 }
 139 #endif
 140
 141                 for (i = n->sel.nkeys; i > 0; i--, key++) {
 142                         int toff = off + key->off + (off2 & key->offmask);
 143                         __be32 *data, hdata;
 144
 145                         if (skb_headroom(skb) + toff > INT_MAX)
 146                                 goto out;
 147
 148                         data = skb_header_pointer(skb, toff, 4, &hdata);
 149                         if (!data)
 150                                 goto out;
 151                         if ((*data ^ key->val) & key->mask) {
 152                                 n = rcu_dereference_bh(n->next);
 153                                 goto next_knode;
 154                         }
 155 #ifdef CONFIG_CLS_U32_PERF
 156                         __this_cpu_inc(n->pf->kcnts[j]);
 157                         j++;
 158 #endif
 159                 }
 160
 161                 ht = rcu_dereference_bh(n->ht_down);
 162                 if (!ht) {
 163 check_terminal:
 164                         if (n->sel.flags & TC_U32_TERMINAL) {
 165
 166                                 *res = n->res;
 167 #ifdef CONFIG_NET_CLS_IND
 168                                 if (!tcf_match_indev(skb, n->ifindex)) {
 169                                         n = rcu_dereference_bh(n->next);
 170                                         goto next_knode;
 171                                 }
 172 #endif
 173 #ifdef CONFIG_CLS_U32_PERF
 174                                 __this_cpu_inc(n->pf->rhit);
 175 #endif
 176                                 r = tcf_exts_exec(skb, &n->exts, res);
 177                                 if (r < 0) {
 178                                         n = rcu_dereference_bh(n->next);
 179                                         goto next_knode;
 180                                 }
 181
 182                                 return r;
 183                         }
 184                         n = rcu_dereference_bh(n->next);
 185                         goto next_knode;
 186                 }
 187
 188                 /* PUSH */
 189                 if (sdepth >= TC_U32_MAXDEPTH)
 190                         goto deadloop;
 191                 stack[sdepth].knode = n;
 192                 stack[sdepth].off = off;
 193                 sdepth++;
 194
 195                 ht = rcu_dereference_bh(n->ht_down);
 196                 sel = 0;
 197                 if (ht->divisor) {
 198                         __be32 *data, hdata;
 199
 200                         data = skb_header_pointer(skb, off + n->sel.hoff, 4,
 201                                                   &hdata);
 202                         if (!data)
 203                                 goto out;
 204                         sel = ht->divisor & u32_hash_fold(*data, &n->sel,
 205                                                           n->fshift);
 206                 }
 207                 if (!(n->sel.flags & (TC_U32_VAROFFSET | TC_U32_OFFSET | TC_U32_EAT)))
 208                         goto next_ht;
 209
 210                 if (n->sel.flags & (TC_U32_OFFSET | TC_U32_VAROFFSET)) {
 211                         off2 = n->sel.off + 3;
 212                         if (n->sel.flags & TC_U32_VAROFFSET) {
 213                                 __be16 *data, hdata;
 214
 215                                 data = skb_header_pointer(skb,
 216                                                           off + n->sel.offoff,
 217                                                           2, &hdata);
 218                                 if (!data)
 219                                         goto out;
 220                                 off2 += ntohs(n->sel.offmask & *data) >>
 221                                         n->sel.offshift;
 222                         }
 223                         off2 &= ~3;
 224                 }
 225                 if (n->sel.flags & TC_U32_EAT) {
 226                         off += off2;
 227                         off2 = 0;
 228                 }
 229
 230                 if (off < skb->len)
 231                         goto next_ht;
 232         }
 233
 234         /* POP */
 235         if (sdepth--) {
 236                 n = stack[sdepth].knode;
 237                 ht = rcu_dereference_bh(n->ht_up);
 238                 off = stack[sdepth].off;
 239                 goto check_terminal;
 240         }
 241 out:
 242         return -1;
 243
 244 deadloop:
 245         net_warn_ratelimited("cls_u32: dead loop\n");
 246         return -1;
 247 }
 248
 249 static struct tc_u_hnode *
 250 u32_lookup_ht(struct tc_u_common *tp_c, u32 handle)
 251 {
 252         struct tc_u_hnode *ht;
 253
 254         for (ht = rtnl_dereference(tp_c->hlist);
 255              ht;
 256              ht = rtnl_dereference(ht->next))
 257                 if (ht->handle == handle)
 258                         break;
 259
 260         return ht;
 261 }
 262
 263 static struct tc_u_knode *
 264 u32_lookup_key(struct tc_u_hnode *ht, u32 handle)
 265 {
 266         unsigned int sel;
 267         struct tc_u_knode *n = NULL;
 268
 269         sel = TC_U32_HASH(handle);
 270         if (sel > ht->divisor)
 271                 goto out;
 272
 273         for (n = rtnl_dereference(ht->ht[sel]);
 274              n;
 275              n = rtnl_dereference(n->next))
 276                 if (n->handle == handle)
 277                         break;
 278 out:
 279         return n;
 280 }
 281
 282
 283 static unsigned long u32_get(struct tcf_proto *tp, u32 handle)
 284 {
 285         struct tc_u_hnode *ht;
 286         struct tc_u_common *tp_c = tp->data;
 287
 288         if (TC_U32_HTID(handle) == TC_U32_ROOT)
 289                 ht = rtnl_dereference(tp->root);
 290         else
 291                 ht = u32_lookup_ht(tp_c, TC_U32_HTID(handle));
 292
 293         if (!ht)
 294                 return 0;
 295
 296         if (TC_U32_KEY(handle) == 0)
 297                 return (unsigned long)ht;
 298
 299         return (unsigned long)u32_lookup_key(ht, handle);
 300 }
 301
 302 static u32 gen_new_htid(struct tc_u_common *tp_c)
 303 {
 304         int i = 0x800;
 305
 306         /* hgenerator only used inside rtnl lock it is safe to increment
 307          * without read _copy_ update semantics
 308          */
 309         do {
 310                 if (++tp_c->hgenerator == 0x7FF)
 311                         tp_c->hgenerator = 1;
 312         } while (--i > 0 && u32_lookup_ht(tp_c, (tp_c->hgenerator|0x800)<<20));
 313
 314         return i > 0 ? (tp_c->hgenerator|0x800)<<20 : 0;
 315 }
 316
 317 static int u32_init(struct tcf_proto *tp)
 318 {
 319         struct tc_u_hnode *root_ht;
 320         struct tc_u_common *tp_c;
 321
 322         tp_c = tp->q->u32_node;
 323
 324         root_ht = kzalloc(sizeof(*root_ht), GFP_KERNEL);
 325         if (root_ht == NULL)
 326                 return -ENOBUFS;
 327
 328         root_ht->divisor = 0;
 329         root_ht->refcnt++;
 330         root_ht->handle = tp_c ? gen_new_htid(tp_c) : 0x80000000;
 331         root_ht->prio = tp->prio;
 332
 333         if (tp_c == NULL) {
 334                 tp_c = kzalloc(sizeof(*tp_c), GFP_KERNEL);
 335                 if (tp_c == NULL) {
 336                         kfree(root_ht);
 337                         return -ENOBUFS;
 338                 }
 339                 tp_c->q = tp->q;
 340                 tp->q->u32_node = tp_c;
 341         }
 342
 343         tp_c->refcnt++;
 344         RCU_INIT_POINTER(root_ht->next, tp_c->hlist);
 345         rcu_assign_pointer(tp_c->hlist, root_ht);
 346         root_ht->tp_c = tp_c;
 347
 348         rcu_assign_pointer(tp->root, root_ht);
 349         tp->data = tp_c;
 350         return 0;
 351 }
 352
 353 static int u32_destroy_key(struct tcf_proto *tp,
 354                            struct tc_u_knode *n,
 355                            bool free_pf)
 356 {
 357         tcf_exts_destroy(&n->exts);
 358         if (n->ht_down)
 359                 n->ht_down->refcnt--;
 360 #ifdef CONFIG_CLS_U32_PERF
 361         if (free_pf)
 362                 free_percpu(n->pf);
 363 #endif
 364 #ifdef CONFIG_CLS_U32_MARK
 365         if (free_pf)
 366                 free_percpu(n->pcpu_success);
 367 #endif
 368         kfree(n);
 369         return 0;
 370 }
 371
 372 /* u32_delete_key_rcu should be called when free'ing a copied
 373  * version of a tc_u_knode obtained from u32_init_knode(). When
 374  * copies are obtained from u32_init_knode() the statistics are
 375  * shared between the old and new copies to allow readers to
 376  * continue to update the statistics during the copy. To support
 377  * this the u32_delete_key_rcu variant does not free the percpu
 378  * statistics.
 379  */
 380 static void u32_delete_key_rcu(struct rcu_head *rcu)
 381 {
 382         struct tc_u_knode *key = container_of(rcu, struct tc_u_knode, rcu);
 383
 384         u32_destroy_key(key->tp, key, false);
 385 }
 386
 387 /* u32_delete_key_freepf_rcu is the rcu callback variant
 388  * that free's the entire structure including the statistics
 389  * percpu variables. Only use this if the key is not a copy
 390  * returned by u32_init_knode(). See u32_delete_key_rcu()
 391  * for the variant that should be used with keys return from
 392  * u32_init_knode()
 393  */
 394 static void u32_delete_key_freepf_rcu(struct rcu_head *rcu)
 395 {
 396         struct tc_u_knode *key = container_of(rcu, struct tc_u_knode, rcu);
 397
 398         u32_destroy_key(key->tp, key, true);
 399 }
 400
 401 static int u32_delete_key(struct tcf_proto *tp, struct tc_u_knode *key)
 402 {
 403         struct tc_u_knode __rcu **kp;
 404         struct tc_u_knode *pkp;
 405         struct tc_u_hnode *ht = rtnl_dereference(key->ht_up);
 406
 407         if (ht) {
 408                 kp = &ht->ht[TC_U32_HASH(key->handle)];
 409                 for (pkp = rtnl_dereference(*kp); pkp;
 410                      kp = &pkp->next, pkp = rtnl_dereference(*kp)) {
 411                         if (pkp == key) {
 412                                 RCU_INIT_POINTER(*kp, key->next);
 413
 414                                 tcf_unbind_filter(tp, &key->res);
 415                                 call_rcu(&key->rcu, u32_delete_key_freepf_rcu);
 416                                 return 0;
 417                         }
 418                 }
 419         }
 420         WARN_ON(1);
 421         return 0;
 422 }
 423
 424 static void u32_clear_hnode(struct tcf_proto *tp, struct tc_u_hnode *ht)
 425 {
 426         struct tc_u_knode *n;
 427         unsigned int h;
 428
 429         for (h = 0; h <= ht->divisor; h++) {
 430                 while ((n = rtnl_dereference(ht->ht[h])) != NULL) {
 431                         RCU_INIT_POINTER(ht->ht[h],
 432                                          rtnl_dereference(n->next));
 433                         tcf_unbind_filter(tp, &n->res);
 434                         call_rcu(&n->rcu, u32_delete_key_freepf_rcu);
 435                 }
 436         }
 437 }
 438
 439 static int u32_destroy_hnode(struct tcf_proto *tp, struct tc_u_hnode *ht)
 440 {
 441         struct tc_u_common *tp_c = tp->data;
 442         struct tc_u_hnode __rcu **hn;
 443         struct tc_u_hnode *phn;
 444
 445         WARN_ON(ht->refcnt);
 446
 447         u32_clear_hnode(tp, ht);
 448
 449         hn = &tp_c->hlist;
 450         for (phn = rtnl_dereference(*hn);
 451              phn;
 452              hn = &phn->next, phn = rtnl_dereference(*hn)) {
 453                 if (phn == ht) {
 454                         RCU_INIT_POINTER(*hn, ht->next);
 455                         kfree_rcu(ht, rcu);
 456                         return 0;
 457                 }
 458         }
 459
 460         return -ENOENT;
 461 }
 462
 463 static void u32_destroy(struct tcf_proto *tp)
 464 {
 465         struct tc_u_common *tp_c = tp->data;
 466         struct tc_u_hnode *root_ht = rtnl_dereference(tp->root);
 467
 468         WARN_ON(root_ht == NULL);
 469
 470         if (root_ht && --root_ht->refcnt == 0)
 471                 u32_destroy_hnode(tp, root_ht);
 472
 473         if (--tp_c->refcnt == 0) {
 474                 struct tc_u_hnode *ht;
 475
 476                 tp->q->u32_node = NULL;
 477
 478                 for (ht = rtnl_dereference(tp_c->hlist);
 479                      ht;
 480                      ht = rtnl_dereference(ht->next)) {
 481                         ht->refcnt--;
 482                         u32_clear_hnode(tp, ht);
 483                 }
 484
 485                 while ((ht = rtnl_dereference(tp_c->hlist)) != NULL) {
 486                         RCU_INIT_POINTER(tp_c->hlist, ht->next);
 487                         kfree_rcu(ht, rcu);
 488                 }
 489
 490                 kfree(tp_c);
 491         }
 492
 493         tp->data = NULL;
 494 }
 495
 496 static int u32_delete(struct tcf_proto *tp, unsigned long arg)
 497 {
 498         struct tc_u_hnode *ht = (struct tc_u_hnode *)arg;
 499         struct tc_u_hnode *root_ht = rtnl_dereference(tp->root);
 500
 501         if (ht == NULL)
 502                 return 0;
 503
 504         if (TC_U32_KEY(ht->handle))
 505                 return u32_delete_key(tp, (struct tc_u_knode *)ht);
 506
 507         if (root_ht == ht)
 508                 return -EINVAL;
 509
 510         if (ht->refcnt == 1) {
 511                 ht->refcnt--;
 512                 u32_destroy_hnode(tp, ht);
 513         } else {
 514                 return -EBUSY;
 515         }
 516
 517         return 0;
 518 }
 519
 520 #define NR_U32_NODE (1<<12)
 521 static u32 gen_new_kid(struct tc_u_hnode *ht, u32 handle)
 522 {
 523         struct tc_u_knode *n;
 524         unsigned long i;
 525         unsigned long *bitmap = kzalloc(BITS_TO_LONGS(NR_U32_NODE) * sizeof(unsigned long),
 526                                         GFP_KERNEL);
 527         if (!bitmap)
 528                 return handle | 0xFFF;
 529
 530         for (n = rtnl_dereference(ht->ht[TC_U32_HASH(handle)]);
 531              n;
 532              n = rtnl_dereference(n->next))
 533                 set_bit(TC_U32_NODE(n->handle), bitmap);
 534
 535         i = find_next_zero_bit(bitmap, NR_U32_NODE, 0x800);
 536         if (i >= NR_U32_NODE)
 537                 i = find_next_zero_bit(bitmap, NR_U32_NODE, 1);
 538
 539         kfree(bitmap);
 540         return handle | (i >= NR_U32_NODE ? 0xFFF : i);
 541 }
 542
 543 static const struct nla_policy u32_policy[TCA_U32_MAX + 1] = {
 544         [TCA_U32_CLASSID]       = { .type = NLA_U32 },
 545         [TCA_U32_HASH]          = { .type = NLA_U32 },
 546         [TCA_U32_LINK]          = { .type = NLA_U32 },
 547         [TCA_U32_DIVISOR]       = { .type = NLA_U32 },
 548         [TCA_U32_SEL]           = { .len = sizeof(struct tc_u32_sel) },
 549         [TCA_U32_INDEV]         = { .type = NLA_STRING, .len = IFNAMSIZ },
 550         [TCA_U32_MARK]          = { .len = sizeof(struct tc_u32_mark) },
 551 };
 552
 553 static int u32_set_parms(struct net *net, struct tcf_proto *tp,
 554                          unsigned long base, struct tc_u_hnode *ht,
 555                          struct tc_u_knode *n, struct nlattr **tb,
 556                          struct nlattr *est, bool ovr)
 557 {
 558         int err;
 559         struct tcf_exts e;
 560
 561         tcf_exts_init(&e, TCA_U32_ACT, TCA_U32_POLICE);
 562         err = tcf_exts_validate(net, tp, tb, est, &e, ovr);
 563         if (err < 0)
 564                 return err;
 565
 566         err = -EINVAL;
 567         if (tb[TCA_U32_LINK]) {
 568                 u32 handle = nla_get_u32(tb[TCA_U32_LINK]);
 569                 struct tc_u_hnode *ht_down = NULL, *ht_old;
 570
 571                 if (TC_U32_KEY(handle))
 572                         goto errout;
 573
 574                 if (handle) {
 575                         ht_down = u32_lookup_ht(ht->tp_c, handle);
 576
 577                         if (ht_down == NULL)
 578                                 goto errout;
 579                         ht_down->refcnt++;
 580                 }
 581
 582                 ht_old = rtnl_dereference(n->ht_down);
 583                 rcu_assign_pointer(n->ht_down, ht_down);
 584
 585                 if (ht_old)
 586                         ht_old->refcnt--;
 587         }
 588         if (tb[TCA_U32_CLASSID]) {
 589                 n->res.classid = nla_get_u32(tb[TCA_U32_CLASSID]);
 590                 tcf_bind_filter(tp, &n->res, base);
 591         }
 592
 593 #ifdef CONFIG_NET_CLS_IND
 594         if (tb[TCA_U32_INDEV]) {
 595                 int ret;
 596                 ret = tcf_change_indev(net, tb[TCA_U32_INDEV]);
 597                 if (ret < 0)
 598                         goto errout;
 599                 n->ifindex = ret;
 600         }
 601 #endif
 602         tcf_exts_change(tp, &n->exts, &e);
 603
 604         return 0;
 605 errout:
 606         tcf_exts_destroy(&e);
 607         return err;
 608 }
 609
 610 static void u32_replace_knode(struct tcf_proto *tp,
 611                               struct tc_u_common *tp_c,
 612                               struct tc_u_knode *n)
 613 {
 614         struct tc_u_knode __rcu **ins;
 615         struct tc_u_knode *pins;
 616         struct tc_u_hnode *ht;
 617
 618         if (TC_U32_HTID(n->handle) == TC_U32_ROOT)
 619                 ht = rtnl_dereference(tp->root);
 620         else
 621                 ht = u32_lookup_ht(tp_c, TC_U32_HTID(n->handle));
 622
 623         ins = &ht->ht[TC_U32_HASH(n->handle)];
 624
 625         /* The node must always exist for it to be replaced if this is not the
 626          * case then something went very wrong elsewhere.
 627          */
 628         for (pins = rtnl_dereference(*ins); ;
 629              ins = &pins->next, pins = rtnl_dereference(*ins))
 630                 if (pins->handle == n->handle)
 631                         break;
 632
 633         RCU_INIT_POINTER(n->next, pins->next);
 634         rcu_assign_pointer(*ins, n);
 635 }
 636
 637 static struct tc_u_knode *u32_init_knode(struct tcf_proto *tp,
 638                                          struct tc_u_knode *n)
 639 {
 640         struct tc_u_knode *new;
 641         struct tc_u32_sel *s = &n->sel;
 642
 643         new = kzalloc(sizeof(*n) + s->nkeys*sizeof(struct tc_u32_key),
 644                       GFP_KERNEL);
 645
 646         if (!new)
 647                 return NULL;
 648
 649         RCU_INIT_POINTER(new->next, n->next);
 650         new->handle = n->handle;
 651         RCU_INIT_POINTER(new->ht_up, n->ht_up);
 652
 653 #ifdef CONFIG_NET_CLS_IND
 654         new->ifindex = n->ifindex;
 655 #endif
 656         new->fshift = n->fshift;
 657         new->res = n->res;
 658         RCU_INIT_POINTER(new->ht_down, n->ht_down);
 659
 660         /* bump reference count as long as we hold pointer to structure */
 661         if (new->ht_down)
 662                 new->ht_down->refcnt++;
 663
 664 #ifdef CONFIG_CLS_U32_PERF
 665         /* Statistics may be incremented by readers during update
 666          * so we must keep them in tact. When the node is later destroyed
 667          * a special destroy call must be made to not free the pf memory.
 668          */
 669         new->pf = n->pf;
 670 #endif
 671
 672 #ifdef CONFIG_CLS_U32_MARK
 673         new->val = n->val;
 674         new->mask = n->mask;
 675         /* Similarly success statistics must be moved as pointers */
 676         new->pcpu_success = n->pcpu_success;
 677 #endif
 678         new->tp = tp;
 679         memcpy(&new->sel, s, sizeof(*s) + s->nkeys*sizeof(struct tc_u32_key));
 680
 681         tcf_exts_init(&new->exts, TCA_U32_ACT, TCA_U32_POLICE);
 682
 683         return new;
 684 }
 685
 686 static int u32_change(struct net *net, struct sk_buff *in_skb,
 687                       struct tcf_proto *tp, unsigned long base, u32 handle,
 688                       struct nlattr **tca,
 689                       unsigned long *arg, bool ovr)
 690 {
 691         struct tc_u_common *tp_c = tp->data;
 692         struct tc_u_hnode *ht;
 693         struct tc_u_knode *n;
 694         struct tc_u32_sel *s;
 695         struct nlattr *opt = tca[TCA_OPTIONS];
 696         struct nlattr *tb[TCA_U32_MAX + 1];
 697         u32 htid;
 698         int err;
 699 #ifdef CONFIG_CLS_U32_PERF
 700         size_t size;
 701 #endif
 702
 703         if (opt == NULL)
 704                 return handle ? -EINVAL : 0;
 705
 706         err = nla_parse_nested(tb, TCA_U32_MAX, opt, u32_policy);
 707         if (err < 0)
 708                 return err;
 709
 710         n = (struct tc_u_knode *)*arg;
 711         if (n) {
 712                 struct tc_u_knode *new;
 713
 714                 if (TC_U32_KEY(n->handle) == 0)
 715                         return -EINVAL;
 716
 717                 new = u32_init_knode(tp, n);
 718                 if (!new)
 719                         return -ENOMEM;
 720
 721                 err = u32_set_parms(net, tp, base,
 722                                     rtnl_dereference(n->ht_up), new, tb,
 723                                     tca[TCA_RATE], ovr);
 724
 725                 if (err) {
 726                         u32_destroy_key(tp, new, false);
 727                         return err;
 728                 }
 729
 730                 u32_replace_knode(tp, tp_c, new);
 731                 tcf_unbind_filter(tp, &n->res);
 732                 call_rcu(&n->rcu, u32_delete_key_rcu);
 733                 return 0;
 734         }
 735
 736         if (tb[TCA_U32_DIVISOR]) {
 737                 unsigned int divisor = nla_get_u32(tb[TCA_U32_DIVISOR]);
 738
 739                 if (--divisor > 0x100)
 740                         return -EINVAL;
 741                 if (TC_U32_KEY(handle))
 742                         return -EINVAL;
 743                 if (handle == 0) {
 744                         handle = gen_new_htid(tp->data);
 745                         if (handle == 0)
 746                                 return -ENOMEM;
 747                 }
 748                 ht = kzalloc(sizeof(*ht) + divisor*sizeof(void *), GFP_KERNEL);
 749                 if (ht == NULL)
 750                         return -ENOBUFS;
 751                 ht->tp_c = tp_c;
 752                 ht->refcnt = 1;
 753                 ht->divisor = divisor;
 754                 ht->handle = handle;
 755                 ht->prio = tp->prio;
 756                 RCU_INIT_POINTER(ht->next, tp_c->hlist);
 757                 rcu_assign_pointer(tp_c->hlist, ht);
 758                 *arg = (unsigned long)ht;
 759                 return 0;
 760         }
 761
 762         if (tb[TCA_U32_HASH]) {
 763                 htid = nla_get_u32(tb[TCA_U32_HASH]);
 764                 if (TC_U32_HTID(htid) == TC_U32_ROOT) {
 765                         ht = rtnl_dereference(tp->root);
 766                         htid = ht->handle;
 767                 } else {
 768                         ht = u32_lookup_ht(tp->data, TC_U32_HTID(htid));
 769                         if (ht == NULL)
 770                                 return -EINVAL;
 771                 }
 772         } else {
 773                 ht = rtnl_dereference(tp->root);
 774                 htid = ht->handle;
 775         }
 776
 777         if (ht->divisor < TC_U32_HASH(htid))
 778                 return -EINVAL;
 779
 780         if (handle) {
 781                 if (TC_U32_HTID(handle) && TC_U32_HTID(handle^htid))
 782                         return -EINVAL;
 783                 handle = htid | TC_U32_NODE(handle);
 784         } else
 785                 handle = gen_new_kid(ht, htid);
 786
 787         if (tb[TCA_U32_SEL] == NULL)
 788                 return -EINVAL;
 789
 790         s = nla_data(tb[TCA_U32_SEL]);
 791
 792         n = kzalloc(sizeof(*n) + s->nkeys*sizeof(struct tc_u32_key), GFP_KERNEL);
 793         if (n == NULL)
 794                 return -ENOBUFS;
 795
 796 #ifdef CONFIG_CLS_U32_PERF
 797         size = sizeof(struct tc_u32_pcnt) + s->nkeys * sizeof(u64);
 798         n->pf = __alloc_percpu(size, __alignof__(struct tc_u32_pcnt));
 799         if (!n->pf) {
 800                 kfree(n);
 801                 return -ENOBUFS;
 802         }
 803 #endif
 804
 805         memcpy(&n->sel, s, sizeof(*s) + s->nkeys*sizeof(struct tc_u32_key));
 806         RCU_INIT_POINTER(n->ht_up, ht);
 807         n->handle = handle;
 808         n->fshift = s->hmask ? ffs(ntohl(s->hmask)) - 1 : 0;
 809         tcf_exts_init(&n->exts, TCA_U32_ACT, TCA_U32_POLICE);
 810         n->tp = tp;
 811
 812 #ifdef CONFIG_CLS_U32_MARK
 813         n->pcpu_success = alloc_percpu(u32);
 814         if (!n->pcpu_success) {
 815                 err = -ENOMEM;
 816                 goto errout;
 817         }
 818
 819         if (tb[TCA_U32_MARK]) {
 820                 struct tc_u32_mark *mark;
 821
 822                 mark = nla_data(tb[TCA_U32_MARK]);
 823                 n->val = mark->val;
 824                 n->mask = mark->mask;
 825         }
 826 #endif
 827
 828         err = u32_set_parms(net, tp, base, ht, n, tb, tca[TCA_RATE], ovr);
 829         if (err == 0) {
 830                 struct tc_u_knode __rcu **ins;
 831                 struct tc_u_knode *pins;
 832
 833                 ins = &ht->ht[TC_U32_HASH(handle)];
 834                 for (pins = rtnl_dereference(*ins); pins;
 835                      ins = &pins->next, pins = rtnl_dereference(*ins))
 836                         if (TC_U32_NODE(handle) < TC_U32_NODE(pins->handle))
 837                                 break;
 838
 839                 RCU_INIT_POINTER(n->next, pins);
 840                 rcu_assign_pointer(*ins, n);
 841
 842                 *arg = (unsigned long)n;
 843                 return 0;
 844         }
 845
 846 #ifdef CONFIG_CLS_U32_MARK
 847         free_percpu(n->pcpu_success);
 848 errout:
 849 #endif
 850
 851 #ifdef CONFIG_CLS_U32_PERF
 852         free_percpu(n->pf);
 853 #endif
 854         kfree(n);
 855         return err;
 856 }
 857
 858 static void u32_walk(struct tcf_proto *tp, struct tcf_walker *arg)
 859 {
 860         struct tc_u_common *tp_c = tp->data;
 861         struct tc_u_hnode *ht;
 862         struct tc_u_knode *n;
 863         unsigned int h;
 864
 865         if (arg->stop)
 866                 return;
 867
 868         for (ht = rtnl_dereference(tp_c->hlist);
 869              ht;
 870              ht = rtnl_dereference(ht->next)) {
 871                 if (ht->prio != tp->prio)
 872                         continue;
 873                 if (arg->count >= arg->skip) {
 874                         if (arg->fn(tp, (unsigned long)ht, arg) < 0) {
 875                                 arg->stop = 1;
 876                                 return;
 877                         }
 878                 }
 879                 arg->count++;
 880                 for (h = 0; h <= ht->divisor; h++) {
 881                         for (n = rtnl_dereference(ht->ht[h]);
 882                              n;
 883                              n = rtnl_dereference(n->next)) {
 884                                 if (arg->count < arg->skip) {
 885                                         arg->count++;
 886                                         continue;
 887                                 }
 888                                 if (arg->fn(tp, (unsigned long)n, arg) < 0) {
 889                                         arg->stop = 1;
 890                                         return;
 891                                 }
 892                                 arg->count++;
 893                         }
 894                 }
 895         }
 896 }
 897
 898 static int u32_dump(struct net *net, struct tcf_proto *tp, unsigned long fh,
 899                      struct sk_buff *skb, struct tcmsg *t)
 900 {
 901         struct tc_u_knode *n = (struct tc_u_knode *)fh;
 902         struct tc_u_hnode *ht_up, *ht_down;
 903         struct nlattr *nest;
 904
 905         if (n == NULL)
 906                 return skb->len;
 907
 908         t->tcm_handle = n->handle;
 909
 910         nest = nla_nest_start(skb, TCA_OPTIONS);
 911         if (nest == NULL)
 912                 goto nla_put_failure;
 913
 914         if (TC_U32_KEY(n->handle) == 0) {
 915                 struct tc_u_hnode *ht = (struct tc_u_hnode *)fh;
 916                 u32 divisor = ht->divisor + 1;
 917
 918                 if (nla_put_u32(skb, TCA_U32_DIVISOR, divisor))
 919                         goto nla_put_failure;
 920         } else {
 921 #ifdef CONFIG_CLS_U32_PERF
 922                 struct tc_u32_pcnt *gpf;
 923                 int cpu;
 924 #endif
 925
 926                 if (nla_put(skb, TCA_U32_SEL,
 927                             sizeof(n->sel) + n->sel.nkeys*sizeof(struct tc_u32_key),
 928                             &n->sel))
 929                         goto nla_put_failure;
 930
 931                 ht_up = rtnl_dereference(n->ht_up);
 932                 if (ht_up) {
 933                         u32 htid = n->handle & 0xFFFFF000;
 934                         if (nla_put_u32(skb, TCA_U32_HASH, htid))
 935                                 goto nla_put_failure;
 936                 }
 937                 if (n->res.classid &&
 938                     nla_put_u32(skb, TCA_U32_CLASSID, n->res.classid))
 939                         goto nla_put_failure;
 940
 941                 ht_down = rtnl_dereference(n->ht_down);
 942                 if (ht_down &&
 943                     nla_put_u32(skb, TCA_U32_LINK, ht_down->handle))
 944                         goto nla_put_failure;
 945
 946 #ifdef CONFIG_CLS_U32_MARK
 947                 if ((n->val || n->mask)) {
 948                         struct tc_u32_mark mark = {.val = n->val,
 949                                                    .mask = n->mask,
 950                                                    .success = 0};
 951                         int cpum;
 952
 953                         for_each_possible_cpu(cpum) {
 954                                 __u32 cnt = *per_cpu_ptr(n->pcpu_success, cpum);
 955
 956                                 mark.success += cnt;
 957                         }
 958
 959                         if (nla_put(skb, TCA_U32_MARK, sizeof(mark), &mark))
 960                                 goto nla_put_failure;
 961                 }
 962 #endif
 963
 964                 if (tcf_exts_dump(skb, &n->exts) < 0)
 965                         goto nla_put_failure;
 966
 967 #ifdef CONFIG_NET_CLS_IND
 968                 if (n->ifindex) {
 969                         struct net_device *dev;
 970                         dev = __dev_get_by_index(net, n->ifindex);
 971                         if (dev && nla_put_string(skb, TCA_U32_INDEV, dev->name))
 972                                 goto nla_put_failure;
 973                 }
 974 #endif
 975 #ifdef CONFIG_CLS_U32_PERF
 976                 gpf = kzalloc(sizeof(struct tc_u32_pcnt) +
 977                               n->sel.nkeys * sizeof(u64),
 978                               GFP_KERNEL);
 979                 if (!gpf)
 980                         goto nla_put_failure;
 981
 982                 for_each_possible_cpu(cpu) {
 983                         int i;
 984                         struct tc_u32_pcnt *pf = per_cpu_ptr(n->pf, cpu);
 985
 986                         gpf->rcnt += pf->rcnt;
 987                         gpf->rhit += pf->rhit;
 988                         for (i = 0; i < n->sel.nkeys; i++)
 989                                 gpf->kcnts[i] += pf->kcnts[i];
 990                 }
 991
 992                 if (nla_put(skb, TCA_U32_PCNT,
 993                             sizeof(struct tc_u32_pcnt) + n->sel.nkeys*sizeof(u64),
 994                             gpf)) {
 995                         kfree(gpf);
 996                         goto nla_put_failure;
 997                 }
 998                 kfree(gpf);
 999 #endif
1000         }
1001
1002         nla_nest_end(skb, nest);
1003
1004         if (TC_U32_KEY(n->handle))
1005                 if (tcf_exts_dump_stats(skb, &n->exts) < 0)
1006                         goto nla_put_failure;
1007         return skb->len;
1008
1009 nla_put_failure:
1010         nla_nest_cancel(skb, nest);
1011         return -1;
1012 }
1013
1014 static struct tcf_proto_ops cls_u32_ops __read_mostly = {
1015         .kind           =       "u32",
1016         .classify       =       u32_classify,
1017         .init           =       u32_init,
1018         .destroy        =       u32_destroy,
1019         .get            =       u32_get,
1020         .change         =       u32_change,
1021         .delete         =       u32_delete,
1022         .walk           =       u32_walk,
1023         .dump           =       u32_dump,
1024         .owner          =       THIS_MODULE,
1025 };
1026
1027 static int __init init_u32(void)
1028 {
1029         pr_info("u32 classifier\n");
1030 #ifdef CONFIG_CLS_U32_PERF
1031         pr_info("    Performance counters on\n");
1032 #endif
1033 #ifdef CONFIG_NET_CLS_IND
1034         pr_info("    input device check on\n");
1035 #endif
1036 #ifdef CONFIG_NET_CLS_ACT
1037         pr_info("    Actions configured\n");
1038 #endif
1039         return register_tcf_proto_ops(&cls_u32_ops);
1040 }
1041
1042 static void __exit exit_u32(void)
1043 {
1044         unregister_tcf_proto_ops(&cls_u32_ops);
1045 }
1046
1047 module_init(init_u32)
1048 module_exit(exit_u32)
1049 MODULE_LICENSE("GPL");