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 #include <linux/netdevice.h> 47 48 struct tc_u_knode { 49 struct tc_u_knode __rcu *next; 50 u32 handle; 51 struct tc_u_hnode __rcu *ht_up; 52 struct tcf_exts exts; 53 #ifdef CONFIG_NET_CLS_IND 54 int ifindex; 55 #endif 56 u8 fshift; 57 struct tcf_result res; 58 struct tc_u_hnode __rcu *ht_down; 59 #ifdef CONFIG_CLS_U32_PERF 60 struct tc_u32_pcnt __percpu *pf; 61 #endif 62 u32 flags; 63 #ifdef CONFIG_CLS_U32_MARK 64 u32 val; 65 u32 mask; 66 u32 __percpu *pcpu_success; 67 #endif 68 struct tcf_proto *tp; 69 struct rcu_head rcu; 70 /* The 'sel' field MUST be the last field in structure to allow for 71 * tc_u32_keys allocated at end of structure. 72 */ 73 struct tc_u32_sel sel; 74 }; 75 76 struct tc_u_hnode { 77 struct tc_u_hnode __rcu *next; 78 u32 handle; 79 u32 prio; 80 struct tc_u_common *tp_c; 81 int refcnt; 82 unsigned int divisor; 83 struct rcu_head rcu; 84 /* The 'ht' field MUST be the last field in structure to allow for 85 * more entries allocated at end of structure. 86 */ 87 struct tc_u_knode __rcu *ht[1]; 88 }; 89 90 struct tc_u_common { 91 struct tc_u_hnode __rcu *hlist; 92 struct Qdisc *q; 93 int refcnt; 94 u32 hgenerator; 95 struct rcu_head rcu; 96 }; 97 98 static inline unsigned int u32_hash_fold(__be32 key, 99 const struct tc_u32_sel *sel, 100 u8 fshift) 101 { 102 unsigned int h = ntohl(key & sel->hmask) >> fshift; 103 104 return h; 105 } 106 107 static int u32_classify(struct sk_buff *skb, const struct tcf_proto *tp, struct tcf_result *res) 108 { 109 struct { 110 struct tc_u_knode *knode; 111 unsigned int off; 112 } stack[TC_U32_MAXDEPTH]; 113 114 struct tc_u_hnode *ht = rcu_dereference_bh(tp->root); 115 unsigned int off = skb_network_offset(skb); 116 struct tc_u_knode *n; 117 int sdepth = 0; 118 int off2 = 0; 119 int sel = 0; 120 #ifdef CONFIG_CLS_U32_PERF 121 int j; 122 #endif 123 int i, r; 124 125 next_ht: 126 n = rcu_dereference_bh(ht->ht[sel]); 127 128 next_knode: 129 if (n) { 130 struct tc_u32_key *key = n->sel.keys; 131 132 #ifdef CONFIG_CLS_U32_PERF 133 __this_cpu_inc(n->pf->rcnt); 134 j = 0; 135 #endif 136 137 #ifdef CONFIG_CLS_U32_MARK 138 if ((skb->mark & n->mask) != n->val) { 139 n = rcu_dereference_bh(n->next); 140 goto next_knode; 141 } else { 142 __this_cpu_inc(*n->pcpu_success); 143 } 144 #endif 145 146 for (i = n->sel.nkeys; i > 0; i--, key++) { 147 int toff = off + key->off + (off2 & key->offmask); 148 __be32 *data, hdata; 149 150 if (skb_headroom(skb) + toff > INT_MAX) 151 goto out; 152 153 data = skb_header_pointer(skb, toff, 4, &hdata); 154 if (!data) 155 goto out; 156 if ((*data ^ key->val) & key->mask) { 157 n = rcu_dereference_bh(n->next); 158 goto next_knode; 159 } 160 #ifdef CONFIG_CLS_U32_PERF 161 __this_cpu_inc(n->pf->kcnts[j]); 162 j++; 163 #endif 164 } 165 166 ht = rcu_dereference_bh(n->ht_down); 167 if (!ht) { 168 check_terminal: 169 if (n->sel.flags & TC_U32_TERMINAL) { 170 171 *res = n->res; 172 #ifdef CONFIG_NET_CLS_IND 173 if (!tcf_match_indev(skb, n->ifindex)) { 174 n = rcu_dereference_bh(n->next); 175 goto next_knode; 176 } 177 #endif 178 #ifdef CONFIG_CLS_U32_PERF 179 __this_cpu_inc(n->pf->rhit); 180 #endif 181 r = tcf_exts_exec(skb, &n->exts, res); 182 if (r < 0) { 183 n = rcu_dereference_bh(n->next); 184 goto next_knode; 185 } 186 187 return r; 188 } 189 n = rcu_dereference_bh(n->next); 190 goto next_knode; 191 } 192 193 /* PUSH */ 194 if (sdepth >= TC_U32_MAXDEPTH) 195 goto deadloop; 196 stack[sdepth].knode = n; 197 stack[sdepth].off = off; 198 sdepth++; 199 200 ht = rcu_dereference_bh(n->ht_down); 201 sel = 0; 202 if (ht->divisor) { 203 __be32 *data, hdata; 204 205 data = skb_header_pointer(skb, off + n->sel.hoff, 4, 206 &hdata); 207 if (!data) 208 goto out; 209 sel = ht->divisor & u32_hash_fold(*data, &n->sel, 210 n->fshift); 211 } 212 if (!(n->sel.flags & (TC_U32_VAROFFSET | TC_U32_OFFSET | TC_U32_EAT))) 213 goto next_ht; 214 215 if (n->sel.flags & (TC_U32_OFFSET | TC_U32_VAROFFSET)) { 216 off2 = n->sel.off + 3; 217 if (n->sel.flags & TC_U32_VAROFFSET) { 218 __be16 *data, hdata; 219 220 data = skb_header_pointer(skb, 221 off + n->sel.offoff, 222 2, &hdata); 223 if (!data) 224 goto out; 225 off2 += ntohs(n->sel.offmask & *data) >> 226 n->sel.offshift; 227 } 228 off2 &= ~3; 229 } 230 if (n->sel.flags & TC_U32_EAT) { 231 off += off2; 232 off2 = 0; 233 } 234 235 if (off < skb->len) 236 goto next_ht; 237 } 238 239 /* POP */ 240 if (sdepth--) { 241 n = stack[sdepth].knode; 242 ht = rcu_dereference_bh(n->ht_up); 243 off = stack[sdepth].off; 244 goto check_terminal; 245 } 246 out: 247 return -1; 248 249 deadloop: 250 net_warn_ratelimited("cls_u32: dead loop\n"); 251 return -1; 252 } 253 254 static struct tc_u_hnode * 255 u32_lookup_ht(struct tc_u_common *tp_c, u32 handle) 256 { 257 struct tc_u_hnode *ht; 258 259 for (ht = rtnl_dereference(tp_c->hlist); 260 ht; 261 ht = rtnl_dereference(ht->next)) 262 if (ht->handle == handle) 263 break; 264 265 return ht; 266 } 267 268 static struct tc_u_knode * 269 u32_lookup_key(struct tc_u_hnode *ht, u32 handle) 270 { 271 unsigned int sel; 272 struct tc_u_knode *n = NULL; 273 274 sel = TC_U32_HASH(handle); 275 if (sel > ht->divisor) 276 goto out; 277 278 for (n = rtnl_dereference(ht->ht[sel]); 279 n; 280 n = rtnl_dereference(n->next)) 281 if (n->handle == handle) 282 break; 283 out: 284 return n; 285 } 286 287 288 static unsigned long u32_get(struct tcf_proto *tp, u32 handle) 289 { 290 struct tc_u_hnode *ht; 291 struct tc_u_common *tp_c = tp->data; 292 293 if (TC_U32_HTID(handle) == TC_U32_ROOT) 294 ht = rtnl_dereference(tp->root); 295 else 296 ht = u32_lookup_ht(tp_c, TC_U32_HTID(handle)); 297 298 if (!ht) 299 return 0; 300 301 if (TC_U32_KEY(handle) == 0) 302 return (unsigned long)ht; 303 304 return (unsigned long)u32_lookup_key(ht, handle); 305 } 306 307 static u32 gen_new_htid(struct tc_u_common *tp_c) 308 { 309 int i = 0x800; 310 311 /* hgenerator only used inside rtnl lock it is safe to increment 312 * without read _copy_ update semantics 313 */ 314 do { 315 if (++tp_c->hgenerator == 0x7FF) 316 tp_c->hgenerator = 1; 317 } while (--i > 0 && u32_lookup_ht(tp_c, (tp_c->hgenerator|0x800)<<20)); 318 319 return i > 0 ? (tp_c->hgenerator|0x800)<<20 : 0; 320 } 321 322 static int u32_init(struct tcf_proto *tp) 323 { 324 struct tc_u_hnode *root_ht; 325 struct tc_u_common *tp_c; 326 327 tp_c = tp->q->u32_node; 328 329 root_ht = kzalloc(sizeof(*root_ht), GFP_KERNEL); 330 if (root_ht == NULL) 331 return -ENOBUFS; 332 333 root_ht->divisor = 0; 334 root_ht->refcnt++; 335 root_ht->handle = tp_c ? gen_new_htid(tp_c) : 0x80000000; 336 root_ht->prio = tp->prio; 337 338 if (tp_c == NULL) { 339 tp_c = kzalloc(sizeof(*tp_c), GFP_KERNEL); 340 if (tp_c == NULL) { 341 kfree(root_ht); 342 return -ENOBUFS; 343 } 344 tp_c->q = tp->q; 345 tp->q->u32_node = tp_c; 346 } 347 348 tp_c->refcnt++; 349 RCU_INIT_POINTER(root_ht->next, tp_c->hlist); 350 rcu_assign_pointer(tp_c->hlist, root_ht); 351 root_ht->tp_c = tp_c; 352 353 rcu_assign_pointer(tp->root, root_ht); 354 tp->data = tp_c; 355 return 0; 356 } 357 358 static int u32_destroy_key(struct tcf_proto *tp, 359 struct tc_u_knode *n, 360 bool free_pf) 361 { 362 tcf_exts_destroy(&n->exts); 363 if (n->ht_down) 364 n->ht_down->refcnt--; 365 #ifdef CONFIG_CLS_U32_PERF 366 if (free_pf) 367 free_percpu(n->pf); 368 #endif 369 #ifdef CONFIG_CLS_U32_MARK 370 if (free_pf) 371 free_percpu(n->pcpu_success); 372 #endif 373 kfree(n); 374 return 0; 375 } 376 377 /* u32_delete_key_rcu should be called when free'ing a copied 378 * version of a tc_u_knode obtained from u32_init_knode(). When 379 * copies are obtained from u32_init_knode() the statistics are 380 * shared between the old and new copies to allow readers to 381 * continue to update the statistics during the copy. To support 382 * this the u32_delete_key_rcu variant does not free the percpu 383 * statistics. 384 */ 385 static void u32_delete_key_rcu(struct rcu_head *rcu) 386 { 387 struct tc_u_knode *key = container_of(rcu, struct tc_u_knode, rcu); 388 389 u32_destroy_key(key->tp, key, false); 390 } 391 392 /* u32_delete_key_freepf_rcu is the rcu callback variant 393 * that free's the entire structure including the statistics 394 * percpu variables. Only use this if the key is not a copy 395 * returned by u32_init_knode(). See u32_delete_key_rcu() 396 * for the variant that should be used with keys return from 397 * u32_init_knode() 398 */ 399 static void u32_delete_key_freepf_rcu(struct rcu_head *rcu) 400 { 401 struct tc_u_knode *key = container_of(rcu, struct tc_u_knode, rcu); 402 403 u32_destroy_key(key->tp, key, true); 404 } 405 406 static int u32_delete_key(struct tcf_proto *tp, struct tc_u_knode *key) 407 { 408 struct tc_u_knode __rcu **kp; 409 struct tc_u_knode *pkp; 410 struct tc_u_hnode *ht = rtnl_dereference(key->ht_up); 411 412 if (ht) { 413 kp = &ht->ht[TC_U32_HASH(key->handle)]; 414 for (pkp = rtnl_dereference(*kp); pkp; 415 kp = &pkp->next, pkp = rtnl_dereference(*kp)) { 416 if (pkp == key) { 417 RCU_INIT_POINTER(*kp, key->next); 418 419 tcf_unbind_filter(tp, &key->res); 420 call_rcu(&key->rcu, u32_delete_key_freepf_rcu); 421 return 0; 422 } 423 } 424 } 425 WARN_ON(1); 426 return 0; 427 } 428 429 static void u32_remove_hw_knode(struct tcf_proto *tp, u32 handle) 430 { 431 struct net_device *dev = tp->q->dev_queue->dev; 432 struct tc_cls_u32_offload u32_offload = {0}; 433 struct tc_to_netdev offload; 434 435 offload.type = TC_SETUP_CLSU32; 436 offload.cls_u32 = &u32_offload; 437 438 if (tc_should_offload(dev, 0)) { 439 offload.cls_u32->command = TC_CLSU32_DELETE_KNODE; 440 offload.cls_u32->knode.handle = handle; 441 dev->netdev_ops->ndo_setup_tc(dev, tp->q->handle, 442 tp->protocol, &offload); 443 } 444 } 445 446 static void u32_replace_hw_hnode(struct tcf_proto *tp, 447 struct tc_u_hnode *h, 448 u32 flags) 449 { 450 struct net_device *dev = tp->q->dev_queue->dev; 451 struct tc_cls_u32_offload u32_offload = {0}; 452 struct tc_to_netdev offload; 453 454 offload.type = TC_SETUP_CLSU32; 455 offload.cls_u32 = &u32_offload; 456 457 if (tc_should_offload(dev, flags)) { 458 offload.cls_u32->command = TC_CLSU32_NEW_HNODE; 459 offload.cls_u32->hnode.divisor = h->divisor; 460 offload.cls_u32->hnode.handle = h->handle; 461 offload.cls_u32->hnode.prio = h->prio; 462 463 dev->netdev_ops->ndo_setup_tc(dev, tp->q->handle, 464 tp->protocol, &offload); 465 } 466 } 467 468 static void u32_clear_hw_hnode(struct tcf_proto *tp, struct tc_u_hnode *h) 469 { 470 struct net_device *dev = tp->q->dev_queue->dev; 471 struct tc_cls_u32_offload u32_offload = {0}; 472 struct tc_to_netdev offload; 473 474 offload.type = TC_SETUP_CLSU32; 475 offload.cls_u32 = &u32_offload; 476 477 if (tc_should_offload(dev, 0)) { 478 offload.cls_u32->command = TC_CLSU32_DELETE_HNODE; 479 offload.cls_u32->hnode.divisor = h->divisor; 480 offload.cls_u32->hnode.handle = h->handle; 481 offload.cls_u32->hnode.prio = h->prio; 482 483 dev->netdev_ops->ndo_setup_tc(dev, tp->q->handle, 484 tp->protocol, &offload); 485 } 486 } 487 488 static void u32_replace_hw_knode(struct tcf_proto *tp, 489 struct tc_u_knode *n, 490 u32 flags) 491 { 492 struct net_device *dev = tp->q->dev_queue->dev; 493 struct tc_cls_u32_offload u32_offload = {0}; 494 struct tc_to_netdev offload; 495 496 offload.type = TC_SETUP_CLSU32; 497 offload.cls_u32 = &u32_offload; 498 499 if (tc_should_offload(dev, flags)) { 500 offload.cls_u32->command = TC_CLSU32_REPLACE_KNODE; 501 offload.cls_u32->knode.handle = n->handle; 502 offload.cls_u32->knode.fshift = n->fshift; 503 #ifdef CONFIG_CLS_U32_MARK 504 offload.cls_u32->knode.val = n->val; 505 offload.cls_u32->knode.mask = n->mask; 506 #else 507 offload.cls_u32->knode.val = 0; 508 offload.cls_u32->knode.mask = 0; 509 #endif 510 offload.cls_u32->knode.sel = &n->sel; 511 offload.cls_u32->knode.exts = &n->exts; 512 if (n->ht_down) 513 offload.cls_u32->knode.link_handle = n->ht_down->handle; 514 515 dev->netdev_ops->ndo_setup_tc(dev, tp->q->handle, 516 tp->protocol, &offload); 517 } 518 } 519 520 static void u32_clear_hnode(struct tcf_proto *tp, struct tc_u_hnode *ht) 521 { 522 struct tc_u_knode *n; 523 unsigned int h; 524 525 for (h = 0; h <= ht->divisor; h++) { 526 while ((n = rtnl_dereference(ht->ht[h])) != NULL) { 527 RCU_INIT_POINTER(ht->ht[h], 528 rtnl_dereference(n->next)); 529 tcf_unbind_filter(tp, &n->res); 530 u32_remove_hw_knode(tp, n->handle); 531 call_rcu(&n->rcu, u32_delete_key_freepf_rcu); 532 } 533 } 534 } 535 536 static int u32_destroy_hnode(struct tcf_proto *tp, struct tc_u_hnode *ht) 537 { 538 struct tc_u_common *tp_c = tp->data; 539 struct tc_u_hnode __rcu **hn; 540 struct tc_u_hnode *phn; 541 542 WARN_ON(ht->refcnt); 543 544 u32_clear_hnode(tp, ht); 545 546 hn = &tp_c->hlist; 547 for (phn = rtnl_dereference(*hn); 548 phn; 549 hn = &phn->next, phn = rtnl_dereference(*hn)) { 550 if (phn == ht) { 551 u32_clear_hw_hnode(tp, ht); 552 RCU_INIT_POINTER(*hn, ht->next); 553 kfree_rcu(ht, rcu); 554 return 0; 555 } 556 } 557 558 return -ENOENT; 559 } 560 561 static bool ht_empty(struct tc_u_hnode *ht) 562 { 563 unsigned int h; 564 565 for (h = 0; h <= ht->divisor; h++) 566 if (rcu_access_pointer(ht->ht[h])) 567 return false; 568 569 return true; 570 } 571 572 static bool u32_destroy(struct tcf_proto *tp, bool force) 573 { 574 struct tc_u_common *tp_c = tp->data; 575 struct tc_u_hnode *root_ht = rtnl_dereference(tp->root); 576 577 WARN_ON(root_ht == NULL); 578 579 if (!force) { 580 if (root_ht) { 581 if (root_ht->refcnt > 1) 582 return false; 583 if (root_ht->refcnt == 1) { 584 if (!ht_empty(root_ht)) 585 return false; 586 } 587 } 588 589 if (tp_c->refcnt > 1) 590 return false; 591 592 if (tp_c->refcnt == 1) { 593 struct tc_u_hnode *ht; 594 595 for (ht = rtnl_dereference(tp_c->hlist); 596 ht; 597 ht = rtnl_dereference(ht->next)) 598 if (!ht_empty(ht)) 599 return false; 600 } 601 } 602 603 if (root_ht && --root_ht->refcnt == 0) 604 u32_destroy_hnode(tp, root_ht); 605 606 if (--tp_c->refcnt == 0) { 607 struct tc_u_hnode *ht; 608 609 tp->q->u32_node = NULL; 610 611 for (ht = rtnl_dereference(tp_c->hlist); 612 ht; 613 ht = rtnl_dereference(ht->next)) { 614 ht->refcnt--; 615 u32_clear_hnode(tp, ht); 616 } 617 618 while ((ht = rtnl_dereference(tp_c->hlist)) != NULL) { 619 RCU_INIT_POINTER(tp_c->hlist, ht->next); 620 kfree_rcu(ht, rcu); 621 } 622 623 kfree(tp_c); 624 } 625 626 tp->data = NULL; 627 return true; 628 } 629 630 static int u32_delete(struct tcf_proto *tp, unsigned long arg) 631 { 632 struct tc_u_hnode *ht = (struct tc_u_hnode *)arg; 633 struct tc_u_hnode *root_ht = rtnl_dereference(tp->root); 634 635 if (ht == NULL) 636 return 0; 637 638 if (TC_U32_KEY(ht->handle)) { 639 u32_remove_hw_knode(tp, ht->handle); 640 return u32_delete_key(tp, (struct tc_u_knode *)ht); 641 } 642 643 if (root_ht == ht) 644 return -EINVAL; 645 646 if (ht->refcnt == 1) { 647 ht->refcnt--; 648 u32_destroy_hnode(tp, ht); 649 } else { 650 return -EBUSY; 651 } 652 653 return 0; 654 } 655 656 #define NR_U32_NODE (1<<12) 657 static u32 gen_new_kid(struct tc_u_hnode *ht, u32 handle) 658 { 659 struct tc_u_knode *n; 660 unsigned long i; 661 unsigned long *bitmap = kzalloc(BITS_TO_LONGS(NR_U32_NODE) * sizeof(unsigned long), 662 GFP_KERNEL); 663 if (!bitmap) 664 return handle | 0xFFF; 665 666 for (n = rtnl_dereference(ht->ht[TC_U32_HASH(handle)]); 667 n; 668 n = rtnl_dereference(n->next)) 669 set_bit(TC_U32_NODE(n->handle), bitmap); 670 671 i = find_next_zero_bit(bitmap, NR_U32_NODE, 0x800); 672 if (i >= NR_U32_NODE) 673 i = find_next_zero_bit(bitmap, NR_U32_NODE, 1); 674 675 kfree(bitmap); 676 return handle | (i >= NR_U32_NODE ? 0xFFF : i); 677 } 678 679 static const struct nla_policy u32_policy[TCA_U32_MAX + 1] = { 680 [TCA_U32_CLASSID] = { .type = NLA_U32 }, 681 [TCA_U32_HASH] = { .type = NLA_U32 }, 682 [TCA_U32_LINK] = { .type = NLA_U32 }, 683 [TCA_U32_DIVISOR] = { .type = NLA_U32 }, 684 [TCA_U32_SEL] = { .len = sizeof(struct tc_u32_sel) }, 685 [TCA_U32_INDEV] = { .type = NLA_STRING, .len = IFNAMSIZ }, 686 [TCA_U32_MARK] = { .len = sizeof(struct tc_u32_mark) }, 687 [TCA_U32_FLAGS] = { .type = NLA_U32 }, 688 }; 689 690 static int u32_set_parms(struct net *net, struct tcf_proto *tp, 691 unsigned long base, struct tc_u_hnode *ht, 692 struct tc_u_knode *n, struct nlattr **tb, 693 struct nlattr *est, bool ovr) 694 { 695 int err; 696 struct tcf_exts e; 697 698 tcf_exts_init(&e, TCA_U32_ACT, TCA_U32_POLICE); 699 err = tcf_exts_validate(net, tp, tb, est, &e, ovr); 700 if (err < 0) 701 return err; 702 703 err = -EINVAL; 704 if (tb[TCA_U32_LINK]) { 705 u32 handle = nla_get_u32(tb[TCA_U32_LINK]); 706 struct tc_u_hnode *ht_down = NULL, *ht_old; 707 708 if (TC_U32_KEY(handle)) 709 goto errout; 710 711 if (handle) { 712 ht_down = u32_lookup_ht(ht->tp_c, handle); 713 714 if (ht_down == NULL) 715 goto errout; 716 ht_down->refcnt++; 717 } 718 719 ht_old = rtnl_dereference(n->ht_down); 720 rcu_assign_pointer(n->ht_down, ht_down); 721 722 if (ht_old) 723 ht_old->refcnt--; 724 } 725 if (tb[TCA_U32_CLASSID]) { 726 n->res.classid = nla_get_u32(tb[TCA_U32_CLASSID]); 727 tcf_bind_filter(tp, &n->res, base); 728 } 729 730 #ifdef CONFIG_NET_CLS_IND 731 if (tb[TCA_U32_INDEV]) { 732 int ret; 733 ret = tcf_change_indev(net, tb[TCA_U32_INDEV]); 734 if (ret < 0) 735 goto errout; 736 n->ifindex = ret; 737 } 738 #endif 739 tcf_exts_change(tp, &n->exts, &e); 740 741 return 0; 742 errout: 743 tcf_exts_destroy(&e); 744 return err; 745 } 746 747 static void u32_replace_knode(struct tcf_proto *tp, 748 struct tc_u_common *tp_c, 749 struct tc_u_knode *n) 750 { 751 struct tc_u_knode __rcu **ins; 752 struct tc_u_knode *pins; 753 struct tc_u_hnode *ht; 754 755 if (TC_U32_HTID(n->handle) == TC_U32_ROOT) 756 ht = rtnl_dereference(tp->root); 757 else 758 ht = u32_lookup_ht(tp_c, TC_U32_HTID(n->handle)); 759 760 ins = &ht->ht[TC_U32_HASH(n->handle)]; 761 762 /* The node must always exist for it to be replaced if this is not the 763 * case then something went very wrong elsewhere. 764 */ 765 for (pins = rtnl_dereference(*ins); ; 766 ins = &pins->next, pins = rtnl_dereference(*ins)) 767 if (pins->handle == n->handle) 768 break; 769 770 RCU_INIT_POINTER(n->next, pins->next); 771 rcu_assign_pointer(*ins, n); 772 } 773 774 static struct tc_u_knode *u32_init_knode(struct tcf_proto *tp, 775 struct tc_u_knode *n) 776 { 777 struct tc_u_knode *new; 778 struct tc_u32_sel *s = &n->sel; 779 780 new = kzalloc(sizeof(*n) + s->nkeys*sizeof(struct tc_u32_key), 781 GFP_KERNEL); 782 783 if (!new) 784 return NULL; 785 786 RCU_INIT_POINTER(new->next, n->next); 787 new->handle = n->handle; 788 RCU_INIT_POINTER(new->ht_up, n->ht_up); 789 790 #ifdef CONFIG_NET_CLS_IND 791 new->ifindex = n->ifindex; 792 #endif 793 new->fshift = n->fshift; 794 new->res = n->res; 795 new->flags = n->flags; 796 RCU_INIT_POINTER(new->ht_down, n->ht_down); 797 798 /* bump reference count as long as we hold pointer to structure */ 799 if (new->ht_down) 800 new->ht_down->refcnt++; 801 802 #ifdef CONFIG_CLS_U32_PERF 803 /* Statistics may be incremented by readers during update 804 * so we must keep them in tact. When the node is later destroyed 805 * a special destroy call must be made to not free the pf memory. 806 */ 807 new->pf = n->pf; 808 #endif 809 810 #ifdef CONFIG_CLS_U32_MARK 811 new->val = n->val; 812 new->mask = n->mask; 813 /* Similarly success statistics must be moved as pointers */ 814 new->pcpu_success = n->pcpu_success; 815 #endif 816 new->tp = tp; 817 memcpy(&new->sel, s, sizeof(*s) + s->nkeys*sizeof(struct tc_u32_key)); 818 819 tcf_exts_init(&new->exts, TCA_U32_ACT, TCA_U32_POLICE); 820 821 return new; 822 } 823 824 static int u32_change(struct net *net, struct sk_buff *in_skb, 825 struct tcf_proto *tp, unsigned long base, u32 handle, 826 struct nlattr **tca, 827 unsigned long *arg, bool ovr) 828 { 829 struct tc_u_common *tp_c = tp->data; 830 struct tc_u_hnode *ht; 831 struct tc_u_knode *n; 832 struct tc_u32_sel *s; 833 struct nlattr *opt = tca[TCA_OPTIONS]; 834 struct nlattr *tb[TCA_U32_MAX + 1]; 835 u32 htid, flags = 0; 836 int err; 837 #ifdef CONFIG_CLS_U32_PERF 838 size_t size; 839 #endif 840 841 if (opt == NULL) 842 return handle ? -EINVAL : 0; 843 844 err = nla_parse_nested(tb, TCA_U32_MAX, opt, u32_policy); 845 if (err < 0) 846 return err; 847 848 if (tb[TCA_U32_FLAGS]) 849 flags = nla_get_u32(tb[TCA_U32_FLAGS]); 850 851 n = (struct tc_u_knode *)*arg; 852 if (n) { 853 struct tc_u_knode *new; 854 855 if (TC_U32_KEY(n->handle) == 0) 856 return -EINVAL; 857 858 if (n->flags != flags) 859 return -EINVAL; 860 861 new = u32_init_knode(tp, n); 862 if (!new) 863 return -ENOMEM; 864 865 err = u32_set_parms(net, tp, base, 866 rtnl_dereference(n->ht_up), new, tb, 867 tca[TCA_RATE], ovr); 868 869 if (err) { 870 u32_destroy_key(tp, new, false); 871 return err; 872 } 873 874 u32_replace_knode(tp, tp_c, new); 875 tcf_unbind_filter(tp, &n->res); 876 call_rcu(&n->rcu, u32_delete_key_rcu); 877 u32_replace_hw_knode(tp, new, flags); 878 return 0; 879 } 880 881 if (tb[TCA_U32_DIVISOR]) { 882 unsigned int divisor = nla_get_u32(tb[TCA_U32_DIVISOR]); 883 884 if (--divisor > 0x100) 885 return -EINVAL; 886 if (TC_U32_KEY(handle)) 887 return -EINVAL; 888 if (handle == 0) { 889 handle = gen_new_htid(tp->data); 890 if (handle == 0) 891 return -ENOMEM; 892 } 893 ht = kzalloc(sizeof(*ht) + divisor*sizeof(void *), GFP_KERNEL); 894 if (ht == NULL) 895 return -ENOBUFS; 896 ht->tp_c = tp_c; 897 ht->refcnt = 1; 898 ht->divisor = divisor; 899 ht->handle = handle; 900 ht->prio = tp->prio; 901 RCU_INIT_POINTER(ht->next, tp_c->hlist); 902 rcu_assign_pointer(tp_c->hlist, ht); 903 *arg = (unsigned long)ht; 904 905 u32_replace_hw_hnode(tp, ht, flags); 906 return 0; 907 } 908 909 if (tb[TCA_U32_HASH]) { 910 htid = nla_get_u32(tb[TCA_U32_HASH]); 911 if (TC_U32_HTID(htid) == TC_U32_ROOT) { 912 ht = rtnl_dereference(tp->root); 913 htid = ht->handle; 914 } else { 915 ht = u32_lookup_ht(tp->data, TC_U32_HTID(htid)); 916 if (ht == NULL) 917 return -EINVAL; 918 } 919 } else { 920 ht = rtnl_dereference(tp->root); 921 htid = ht->handle; 922 } 923 924 if (ht->divisor < TC_U32_HASH(htid)) 925 return -EINVAL; 926 927 if (handle) { 928 if (TC_U32_HTID(handle) && TC_U32_HTID(handle^htid)) 929 return -EINVAL; 930 handle = htid | TC_U32_NODE(handle); 931 } else 932 handle = gen_new_kid(ht, htid); 933 934 if (tb[TCA_U32_SEL] == NULL) 935 return -EINVAL; 936 937 s = nla_data(tb[TCA_U32_SEL]); 938 939 n = kzalloc(sizeof(*n) + s->nkeys*sizeof(struct tc_u32_key), GFP_KERNEL); 940 if (n == NULL) 941 return -ENOBUFS; 942 943 #ifdef CONFIG_CLS_U32_PERF 944 size = sizeof(struct tc_u32_pcnt) + s->nkeys * sizeof(u64); 945 n->pf = __alloc_percpu(size, __alignof__(struct tc_u32_pcnt)); 946 if (!n->pf) { 947 kfree(n); 948 return -ENOBUFS; 949 } 950 #endif 951 952 memcpy(&n->sel, s, sizeof(*s) + s->nkeys*sizeof(struct tc_u32_key)); 953 RCU_INIT_POINTER(n->ht_up, ht); 954 n->handle = handle; 955 n->fshift = s->hmask ? ffs(ntohl(s->hmask)) - 1 : 0; 956 n->flags = flags; 957 tcf_exts_init(&n->exts, TCA_U32_ACT, TCA_U32_POLICE); 958 n->tp = tp; 959 960 #ifdef CONFIG_CLS_U32_MARK 961 n->pcpu_success = alloc_percpu(u32); 962 if (!n->pcpu_success) { 963 err = -ENOMEM; 964 goto errout; 965 } 966 967 if (tb[TCA_U32_MARK]) { 968 struct tc_u32_mark *mark; 969 970 mark = nla_data(tb[TCA_U32_MARK]); 971 n->val = mark->val; 972 n->mask = mark->mask; 973 } 974 #endif 975 976 err = u32_set_parms(net, tp, base, ht, n, tb, tca[TCA_RATE], ovr); 977 if (err == 0) { 978 struct tc_u_knode __rcu **ins; 979 struct tc_u_knode *pins; 980 981 ins = &ht->ht[TC_U32_HASH(handle)]; 982 for (pins = rtnl_dereference(*ins); pins; 983 ins = &pins->next, pins = rtnl_dereference(*ins)) 984 if (TC_U32_NODE(handle) < TC_U32_NODE(pins->handle)) 985 break; 986 987 RCU_INIT_POINTER(n->next, pins); 988 rcu_assign_pointer(*ins, n); 989 u32_replace_hw_knode(tp, n, flags); 990 *arg = (unsigned long)n; 991 return 0; 992 } 993 994 #ifdef CONFIG_CLS_U32_MARK 995 free_percpu(n->pcpu_success); 996 errout: 997 #endif 998 999 #ifdef CONFIG_CLS_U32_PERF 1000 free_percpu(n->pf); 1001 #endif 1002 kfree(n); 1003 return err; 1004 } 1005 1006 static void u32_walk(struct tcf_proto *tp, struct tcf_walker *arg) 1007 { 1008 struct tc_u_common *tp_c = tp->data; 1009 struct tc_u_hnode *ht; 1010 struct tc_u_knode *n; 1011 unsigned int h; 1012 1013 if (arg->stop) 1014 return; 1015 1016 for (ht = rtnl_dereference(tp_c->hlist); 1017 ht; 1018 ht = rtnl_dereference(ht->next)) { 1019 if (ht->prio != tp->prio) 1020 continue; 1021 if (arg->count >= arg->skip) { 1022 if (arg->fn(tp, (unsigned long)ht, arg) < 0) { 1023 arg->stop = 1; 1024 return; 1025 } 1026 } 1027 arg->count++; 1028 for (h = 0; h <= ht->divisor; h++) { 1029 for (n = rtnl_dereference(ht->ht[h]); 1030 n; 1031 n = rtnl_dereference(n->next)) { 1032 if (arg->count < arg->skip) { 1033 arg->count++; 1034 continue; 1035 } 1036 if (arg->fn(tp, (unsigned long)n, arg) < 0) { 1037 arg->stop = 1; 1038 return; 1039 } 1040 arg->count++; 1041 } 1042 } 1043 } 1044 } 1045 1046 static int u32_dump(struct net *net, struct tcf_proto *tp, unsigned long fh, 1047 struct sk_buff *skb, struct tcmsg *t) 1048 { 1049 struct tc_u_knode *n = (struct tc_u_knode *)fh; 1050 struct tc_u_hnode *ht_up, *ht_down; 1051 struct nlattr *nest; 1052 1053 if (n == NULL) 1054 return skb->len; 1055 1056 t->tcm_handle = n->handle; 1057 1058 nest = nla_nest_start(skb, TCA_OPTIONS); 1059 if (nest == NULL) 1060 goto nla_put_failure; 1061 1062 if (TC_U32_KEY(n->handle) == 0) { 1063 struct tc_u_hnode *ht = (struct tc_u_hnode *)fh; 1064 u32 divisor = ht->divisor + 1; 1065 1066 if (nla_put_u32(skb, TCA_U32_DIVISOR, divisor)) 1067 goto nla_put_failure; 1068 } else { 1069 #ifdef CONFIG_CLS_U32_PERF 1070 struct tc_u32_pcnt *gpf; 1071 int cpu; 1072 #endif 1073 1074 if (nla_put(skb, TCA_U32_SEL, 1075 sizeof(n->sel) + n->sel.nkeys*sizeof(struct tc_u32_key), 1076 &n->sel)) 1077 goto nla_put_failure; 1078 1079 ht_up = rtnl_dereference(n->ht_up); 1080 if (ht_up) { 1081 u32 htid = n->handle & 0xFFFFF000; 1082 if (nla_put_u32(skb, TCA_U32_HASH, htid)) 1083 goto nla_put_failure; 1084 } 1085 if (n->res.classid && 1086 nla_put_u32(skb, TCA_U32_CLASSID, n->res.classid)) 1087 goto nla_put_failure; 1088 1089 ht_down = rtnl_dereference(n->ht_down); 1090 if (ht_down && 1091 nla_put_u32(skb, TCA_U32_LINK, ht_down->handle)) 1092 goto nla_put_failure; 1093 1094 if (n->flags && nla_put_u32(skb, TCA_U32_FLAGS, n->flags)) 1095 goto nla_put_failure; 1096 1097 #ifdef CONFIG_CLS_U32_MARK 1098 if ((n->val || n->mask)) { 1099 struct tc_u32_mark mark = {.val = n->val, 1100 .mask = n->mask, 1101 .success = 0}; 1102 int cpum; 1103 1104 for_each_possible_cpu(cpum) { 1105 __u32 cnt = *per_cpu_ptr(n->pcpu_success, cpum); 1106 1107 mark.success += cnt; 1108 } 1109 1110 if (nla_put(skb, TCA_U32_MARK, sizeof(mark), &mark)) 1111 goto nla_put_failure; 1112 } 1113 #endif 1114 1115 if (tcf_exts_dump(skb, &n->exts) < 0) 1116 goto nla_put_failure; 1117 1118 #ifdef CONFIG_NET_CLS_IND 1119 if (n->ifindex) { 1120 struct net_device *dev; 1121 dev = __dev_get_by_index(net, n->ifindex); 1122 if (dev && nla_put_string(skb, TCA_U32_INDEV, dev->name)) 1123 goto nla_put_failure; 1124 } 1125 #endif 1126 #ifdef CONFIG_CLS_U32_PERF 1127 gpf = kzalloc(sizeof(struct tc_u32_pcnt) + 1128 n->sel.nkeys * sizeof(u64), 1129 GFP_KERNEL); 1130 if (!gpf) 1131 goto nla_put_failure; 1132 1133 for_each_possible_cpu(cpu) { 1134 int i; 1135 struct tc_u32_pcnt *pf = per_cpu_ptr(n->pf, cpu); 1136 1137 gpf->rcnt += pf->rcnt; 1138 gpf->rhit += pf->rhit; 1139 for (i = 0; i < n->sel.nkeys; i++) 1140 gpf->kcnts[i] += pf->kcnts[i]; 1141 } 1142 1143 if (nla_put(skb, TCA_U32_PCNT, 1144 sizeof(struct tc_u32_pcnt) + n->sel.nkeys*sizeof(u64), 1145 gpf)) { 1146 kfree(gpf); 1147 goto nla_put_failure; 1148 } 1149 kfree(gpf); 1150 #endif 1151 } 1152 1153 nla_nest_end(skb, nest); 1154 1155 if (TC_U32_KEY(n->handle)) 1156 if (tcf_exts_dump_stats(skb, &n->exts) < 0) 1157 goto nla_put_failure; 1158 return skb->len; 1159 1160 nla_put_failure: 1161 nla_nest_cancel(skb, nest); 1162 return -1; 1163 } 1164 1165 static struct tcf_proto_ops cls_u32_ops __read_mostly = { 1166 .kind = "u32", 1167 .classify = u32_classify, 1168 .init = u32_init, 1169 .destroy = u32_destroy, 1170 .get = u32_get, 1171 .change = u32_change, 1172 .delete = u32_delete, 1173 .walk = u32_walk, 1174 .dump = u32_dump, 1175 .owner = THIS_MODULE, 1176 }; 1177 1178 static int __init init_u32(void) 1179 { 1180 pr_info("u32 classifier\n"); 1181 #ifdef CONFIG_CLS_U32_PERF 1182 pr_info(" Performance counters on\n"); 1183 #endif 1184 #ifdef CONFIG_NET_CLS_IND 1185 pr_info(" input device check on\n"); 1186 #endif 1187 #ifdef CONFIG_NET_CLS_ACT 1188 pr_info(" Actions configured\n"); 1189 #endif 1190 return register_tcf_proto_ops(&cls_u32_ops); 1191 } 1192 1193 static void __exit exit_u32(void) 1194 { 1195 unregister_tcf_proto_ops(&cls_u32_ops); 1196 } 1197 1198 module_init(init_u32) 1199 module_exit(exit_u32) 1200 MODULE_LICENSE("GPL"); 1201