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 if (tc_skip_sw(n->flags)) { 138 n = rcu_dereference_bh(n->next); 139 goto next_knode; 140 } 141 142 #ifdef CONFIG_CLS_U32_MARK 143 if ((skb->mark & n->mask) != n->val) { 144 n = rcu_dereference_bh(n->next); 145 goto next_knode; 146 } else { 147 __this_cpu_inc(*n->pcpu_success); 148 } 149 #endif 150 151 for (i = n->sel.nkeys; i > 0; i--, key++) { 152 int toff = off + key->off + (off2 & key->offmask); 153 __be32 *data, hdata; 154 155 if (skb_headroom(skb) + toff > INT_MAX) 156 goto out; 157 158 data = skb_header_pointer(skb, toff, 4, &hdata); 159 if (!data) 160 goto out; 161 if ((*data ^ key->val) & key->mask) { 162 n = rcu_dereference_bh(n->next); 163 goto next_knode; 164 } 165 #ifdef CONFIG_CLS_U32_PERF 166 __this_cpu_inc(n->pf->kcnts[j]); 167 j++; 168 #endif 169 } 170 171 ht = rcu_dereference_bh(n->ht_down); 172 if (!ht) { 173 check_terminal: 174 if (n->sel.flags & TC_U32_TERMINAL) { 175 176 *res = n->res; 177 #ifdef CONFIG_NET_CLS_IND 178 if (!tcf_match_indev(skb, n->ifindex)) { 179 n = rcu_dereference_bh(n->next); 180 goto next_knode; 181 } 182 #endif 183 #ifdef CONFIG_CLS_U32_PERF 184 __this_cpu_inc(n->pf->rhit); 185 #endif 186 r = tcf_exts_exec(skb, &n->exts, res); 187 if (r < 0) { 188 n = rcu_dereference_bh(n->next); 189 goto next_knode; 190 } 191 192 return r; 193 } 194 n = rcu_dereference_bh(n->next); 195 goto next_knode; 196 } 197 198 /* PUSH */ 199 if (sdepth >= TC_U32_MAXDEPTH) 200 goto deadloop; 201 stack[sdepth].knode = n; 202 stack[sdepth].off = off; 203 sdepth++; 204 205 ht = rcu_dereference_bh(n->ht_down); 206 sel = 0; 207 if (ht->divisor) { 208 __be32 *data, hdata; 209 210 data = skb_header_pointer(skb, off + n->sel.hoff, 4, 211 &hdata); 212 if (!data) 213 goto out; 214 sel = ht->divisor & u32_hash_fold(*data, &n->sel, 215 n->fshift); 216 } 217 if (!(n->sel.flags & (TC_U32_VAROFFSET | TC_U32_OFFSET | TC_U32_EAT))) 218 goto next_ht; 219 220 if (n->sel.flags & (TC_U32_OFFSET | TC_U32_VAROFFSET)) { 221 off2 = n->sel.off + 3; 222 if (n->sel.flags & TC_U32_VAROFFSET) { 223 __be16 *data, hdata; 224 225 data = skb_header_pointer(skb, 226 off + n->sel.offoff, 227 2, &hdata); 228 if (!data) 229 goto out; 230 off2 += ntohs(n->sel.offmask & *data) >> 231 n->sel.offshift; 232 } 233 off2 &= ~3; 234 } 235 if (n->sel.flags & TC_U32_EAT) { 236 off += off2; 237 off2 = 0; 238 } 239 240 if (off < skb->len) 241 goto next_ht; 242 } 243 244 /* POP */ 245 if (sdepth--) { 246 n = stack[sdepth].knode; 247 ht = rcu_dereference_bh(n->ht_up); 248 off = stack[sdepth].off; 249 goto check_terminal; 250 } 251 out: 252 return -1; 253 254 deadloop: 255 net_warn_ratelimited("cls_u32: dead loop\n"); 256 return -1; 257 } 258 259 static struct tc_u_hnode * 260 u32_lookup_ht(struct tc_u_common *tp_c, u32 handle) 261 { 262 struct tc_u_hnode *ht; 263 264 for (ht = rtnl_dereference(tp_c->hlist); 265 ht; 266 ht = rtnl_dereference(ht->next)) 267 if (ht->handle == handle) 268 break; 269 270 return ht; 271 } 272 273 static struct tc_u_knode * 274 u32_lookup_key(struct tc_u_hnode *ht, u32 handle) 275 { 276 unsigned int sel; 277 struct tc_u_knode *n = NULL; 278 279 sel = TC_U32_HASH(handle); 280 if (sel > ht->divisor) 281 goto out; 282 283 for (n = rtnl_dereference(ht->ht[sel]); 284 n; 285 n = rtnl_dereference(n->next)) 286 if (n->handle == handle) 287 break; 288 out: 289 return n; 290 } 291 292 293 static unsigned long u32_get(struct tcf_proto *tp, u32 handle) 294 { 295 struct tc_u_hnode *ht; 296 struct tc_u_common *tp_c = tp->data; 297 298 if (TC_U32_HTID(handle) == TC_U32_ROOT) 299 ht = rtnl_dereference(tp->root); 300 else 301 ht = u32_lookup_ht(tp_c, TC_U32_HTID(handle)); 302 303 if (!ht) 304 return 0; 305 306 if (TC_U32_KEY(handle) == 0) 307 return (unsigned long)ht; 308 309 return (unsigned long)u32_lookup_key(ht, handle); 310 } 311 312 static u32 gen_new_htid(struct tc_u_common *tp_c) 313 { 314 int i = 0x800; 315 316 /* hgenerator only used inside rtnl lock it is safe to increment 317 * without read _copy_ update semantics 318 */ 319 do { 320 if (++tp_c->hgenerator == 0x7FF) 321 tp_c->hgenerator = 1; 322 } while (--i > 0 && u32_lookup_ht(tp_c, (tp_c->hgenerator|0x800)<<20)); 323 324 return i > 0 ? (tp_c->hgenerator|0x800)<<20 : 0; 325 } 326 327 static int u32_init(struct tcf_proto *tp) 328 { 329 struct tc_u_hnode *root_ht; 330 struct tc_u_common *tp_c; 331 332 tp_c = tp->q->u32_node; 333 334 root_ht = kzalloc(sizeof(*root_ht), GFP_KERNEL); 335 if (root_ht == NULL) 336 return -ENOBUFS; 337 338 root_ht->divisor = 0; 339 root_ht->refcnt++; 340 root_ht->handle = tp_c ? gen_new_htid(tp_c) : 0x80000000; 341 root_ht->prio = tp->prio; 342 343 if (tp_c == NULL) { 344 tp_c = kzalloc(sizeof(*tp_c), GFP_KERNEL); 345 if (tp_c == NULL) { 346 kfree(root_ht); 347 return -ENOBUFS; 348 } 349 tp_c->q = tp->q; 350 tp->q->u32_node = tp_c; 351 } 352 353 tp_c->refcnt++; 354 RCU_INIT_POINTER(root_ht->next, tp_c->hlist); 355 rcu_assign_pointer(tp_c->hlist, root_ht); 356 root_ht->tp_c = tp_c; 357 358 rcu_assign_pointer(tp->root, root_ht); 359 tp->data = tp_c; 360 return 0; 361 } 362 363 static int u32_destroy_key(struct tcf_proto *tp, 364 struct tc_u_knode *n, 365 bool free_pf) 366 { 367 tcf_exts_destroy(&n->exts); 368 if (n->ht_down) 369 n->ht_down->refcnt--; 370 #ifdef CONFIG_CLS_U32_PERF 371 if (free_pf) 372 free_percpu(n->pf); 373 #endif 374 #ifdef CONFIG_CLS_U32_MARK 375 if (free_pf) 376 free_percpu(n->pcpu_success); 377 #endif 378 kfree(n); 379 return 0; 380 } 381 382 /* u32_delete_key_rcu should be called when free'ing a copied 383 * version of a tc_u_knode obtained from u32_init_knode(). When 384 * copies are obtained from u32_init_knode() the statistics are 385 * shared between the old and new copies to allow readers to 386 * continue to update the statistics during the copy. To support 387 * this the u32_delete_key_rcu variant does not free the percpu 388 * statistics. 389 */ 390 static void u32_delete_key_rcu(struct rcu_head *rcu) 391 { 392 struct tc_u_knode *key = container_of(rcu, struct tc_u_knode, rcu); 393 394 u32_destroy_key(key->tp, key, false); 395 } 396 397 /* u32_delete_key_freepf_rcu is the rcu callback variant 398 * that free's the entire structure including the statistics 399 * percpu variables. Only use this if the key is not a copy 400 * returned by u32_init_knode(). See u32_delete_key_rcu() 401 * for the variant that should be used with keys return from 402 * u32_init_knode() 403 */ 404 static void u32_delete_key_freepf_rcu(struct rcu_head *rcu) 405 { 406 struct tc_u_knode *key = container_of(rcu, struct tc_u_knode, rcu); 407 408 u32_destroy_key(key->tp, key, true); 409 } 410 411 static int u32_delete_key(struct tcf_proto *tp, struct tc_u_knode *key) 412 { 413 struct tc_u_knode __rcu **kp; 414 struct tc_u_knode *pkp; 415 struct tc_u_hnode *ht = rtnl_dereference(key->ht_up); 416 417 if (ht) { 418 kp = &ht->ht[TC_U32_HASH(key->handle)]; 419 for (pkp = rtnl_dereference(*kp); pkp; 420 kp = &pkp->next, pkp = rtnl_dereference(*kp)) { 421 if (pkp == key) { 422 RCU_INIT_POINTER(*kp, key->next); 423 424 tcf_unbind_filter(tp, &key->res); 425 call_rcu(&key->rcu, u32_delete_key_freepf_rcu); 426 return 0; 427 } 428 } 429 } 430 WARN_ON(1); 431 return 0; 432 } 433 434 static void u32_remove_hw_knode(struct tcf_proto *tp, u32 handle) 435 { 436 struct net_device *dev = tp->q->dev_queue->dev; 437 struct tc_cls_u32_offload u32_offload = {0}; 438 struct tc_to_netdev offload; 439 440 offload.type = TC_SETUP_CLSU32; 441 offload.cls_u32 = &u32_offload; 442 443 if (tc_should_offload(dev, 0)) { 444 offload.cls_u32->command = TC_CLSU32_DELETE_KNODE; 445 offload.cls_u32->knode.handle = handle; 446 dev->netdev_ops->ndo_setup_tc(dev, tp->q->handle, 447 tp->protocol, &offload); 448 } 449 } 450 451 static int u32_replace_hw_hnode(struct tcf_proto *tp, 452 struct tc_u_hnode *h, 453 u32 flags) 454 { 455 struct net_device *dev = tp->q->dev_queue->dev; 456 struct tc_cls_u32_offload u32_offload = {0}; 457 struct tc_to_netdev offload; 458 int err; 459 460 offload.type = TC_SETUP_CLSU32; 461 offload.cls_u32 = &u32_offload; 462 463 if (tc_should_offload(dev, flags)) { 464 offload.cls_u32->command = TC_CLSU32_NEW_HNODE; 465 offload.cls_u32->hnode.divisor = h->divisor; 466 offload.cls_u32->hnode.handle = h->handle; 467 offload.cls_u32->hnode.prio = h->prio; 468 469 err = dev->netdev_ops->ndo_setup_tc(dev, tp->q->handle, 470 tp->protocol, &offload); 471 if (tc_skip_sw(flags)) 472 return err; 473 } 474 475 return 0; 476 } 477 478 static void u32_clear_hw_hnode(struct tcf_proto *tp, struct tc_u_hnode *h) 479 { 480 struct net_device *dev = tp->q->dev_queue->dev; 481 struct tc_cls_u32_offload u32_offload = {0}; 482 struct tc_to_netdev offload; 483 484 offload.type = TC_SETUP_CLSU32; 485 offload.cls_u32 = &u32_offload; 486 487 if (tc_should_offload(dev, 0)) { 488 offload.cls_u32->command = TC_CLSU32_DELETE_HNODE; 489 offload.cls_u32->hnode.divisor = h->divisor; 490 offload.cls_u32->hnode.handle = h->handle; 491 offload.cls_u32->hnode.prio = h->prio; 492 493 dev->netdev_ops->ndo_setup_tc(dev, tp->q->handle, 494 tp->protocol, &offload); 495 } 496 } 497 498 static int u32_replace_hw_knode(struct tcf_proto *tp, 499 struct tc_u_knode *n, 500 u32 flags) 501 { 502 struct net_device *dev = tp->q->dev_queue->dev; 503 struct tc_cls_u32_offload u32_offload = {0}; 504 struct tc_to_netdev offload; 505 int err; 506 507 offload.type = TC_SETUP_CLSU32; 508 offload.cls_u32 = &u32_offload; 509 510 if (tc_should_offload(dev, flags)) { 511 offload.cls_u32->command = TC_CLSU32_REPLACE_KNODE; 512 offload.cls_u32->knode.handle = n->handle; 513 offload.cls_u32->knode.fshift = n->fshift; 514 #ifdef CONFIG_CLS_U32_MARK 515 offload.cls_u32->knode.val = n->val; 516 offload.cls_u32->knode.mask = n->mask; 517 #else 518 offload.cls_u32->knode.val = 0; 519 offload.cls_u32->knode.mask = 0; 520 #endif 521 offload.cls_u32->knode.sel = &n->sel; 522 offload.cls_u32->knode.exts = &n->exts; 523 if (n->ht_down) 524 offload.cls_u32->knode.link_handle = n->ht_down->handle; 525 526 err = dev->netdev_ops->ndo_setup_tc(dev, tp->q->handle, 527 tp->protocol, &offload); 528 if (tc_skip_sw(flags)) 529 return err; 530 } 531 532 return 0; 533 } 534 535 static void u32_clear_hnode(struct tcf_proto *tp, struct tc_u_hnode *ht) 536 { 537 struct tc_u_knode *n; 538 unsigned int h; 539 540 for (h = 0; h <= ht->divisor; h++) { 541 while ((n = rtnl_dereference(ht->ht[h])) != NULL) { 542 RCU_INIT_POINTER(ht->ht[h], 543 rtnl_dereference(n->next)); 544 tcf_unbind_filter(tp, &n->res); 545 u32_remove_hw_knode(tp, n->handle); 546 call_rcu(&n->rcu, u32_delete_key_freepf_rcu); 547 } 548 } 549 } 550 551 static int u32_destroy_hnode(struct tcf_proto *tp, struct tc_u_hnode *ht) 552 { 553 struct tc_u_common *tp_c = tp->data; 554 struct tc_u_hnode __rcu **hn; 555 struct tc_u_hnode *phn; 556 557 WARN_ON(ht->refcnt); 558 559 u32_clear_hnode(tp, ht); 560 561 hn = &tp_c->hlist; 562 for (phn = rtnl_dereference(*hn); 563 phn; 564 hn = &phn->next, phn = rtnl_dereference(*hn)) { 565 if (phn == ht) { 566 u32_clear_hw_hnode(tp, ht); 567 RCU_INIT_POINTER(*hn, ht->next); 568 kfree_rcu(ht, rcu); 569 return 0; 570 } 571 } 572 573 return -ENOENT; 574 } 575 576 static bool ht_empty(struct tc_u_hnode *ht) 577 { 578 unsigned int h; 579 580 for (h = 0; h <= ht->divisor; h++) 581 if (rcu_access_pointer(ht->ht[h])) 582 return false; 583 584 return true; 585 } 586 587 static bool u32_destroy(struct tcf_proto *tp, bool force) 588 { 589 struct tc_u_common *tp_c = tp->data; 590 struct tc_u_hnode *root_ht = rtnl_dereference(tp->root); 591 592 WARN_ON(root_ht == NULL); 593 594 if (!force) { 595 if (root_ht) { 596 if (root_ht->refcnt > 1) 597 return false; 598 if (root_ht->refcnt == 1) { 599 if (!ht_empty(root_ht)) 600 return false; 601 } 602 } 603 604 if (tp_c->refcnt > 1) 605 return false; 606 607 if (tp_c->refcnt == 1) { 608 struct tc_u_hnode *ht; 609 610 for (ht = rtnl_dereference(tp_c->hlist); 611 ht; 612 ht = rtnl_dereference(ht->next)) 613 if (!ht_empty(ht)) 614 return false; 615 } 616 } 617 618 if (root_ht && --root_ht->refcnt == 0) 619 u32_destroy_hnode(tp, root_ht); 620 621 if (--tp_c->refcnt == 0) { 622 struct tc_u_hnode *ht; 623 624 tp->q->u32_node = NULL; 625 626 for (ht = rtnl_dereference(tp_c->hlist); 627 ht; 628 ht = rtnl_dereference(ht->next)) { 629 ht->refcnt--; 630 u32_clear_hnode(tp, ht); 631 } 632 633 while ((ht = rtnl_dereference(tp_c->hlist)) != NULL) { 634 RCU_INIT_POINTER(tp_c->hlist, ht->next); 635 kfree_rcu(ht, rcu); 636 } 637 638 kfree(tp_c); 639 } 640 641 tp->data = NULL; 642 return true; 643 } 644 645 static int u32_delete(struct tcf_proto *tp, unsigned long arg) 646 { 647 struct tc_u_hnode *ht = (struct tc_u_hnode *)arg; 648 struct tc_u_hnode *root_ht = rtnl_dereference(tp->root); 649 650 if (ht == NULL) 651 return 0; 652 653 if (TC_U32_KEY(ht->handle)) { 654 u32_remove_hw_knode(tp, ht->handle); 655 return u32_delete_key(tp, (struct tc_u_knode *)ht); 656 } 657 658 if (root_ht == ht) 659 return -EINVAL; 660 661 if (ht->refcnt == 1) { 662 ht->refcnt--; 663 u32_destroy_hnode(tp, ht); 664 } else { 665 return -EBUSY; 666 } 667 668 return 0; 669 } 670 671 #define NR_U32_NODE (1<<12) 672 static u32 gen_new_kid(struct tc_u_hnode *ht, u32 handle) 673 { 674 struct tc_u_knode *n; 675 unsigned long i; 676 unsigned long *bitmap = kzalloc(BITS_TO_LONGS(NR_U32_NODE) * sizeof(unsigned long), 677 GFP_KERNEL); 678 if (!bitmap) 679 return handle | 0xFFF; 680 681 for (n = rtnl_dereference(ht->ht[TC_U32_HASH(handle)]); 682 n; 683 n = rtnl_dereference(n->next)) 684 set_bit(TC_U32_NODE(n->handle), bitmap); 685 686 i = find_next_zero_bit(bitmap, NR_U32_NODE, 0x800); 687 if (i >= NR_U32_NODE) 688 i = find_next_zero_bit(bitmap, NR_U32_NODE, 1); 689 690 kfree(bitmap); 691 return handle | (i >= NR_U32_NODE ? 0xFFF : i); 692 } 693 694 static const struct nla_policy u32_policy[TCA_U32_MAX + 1] = { 695 [TCA_U32_CLASSID] = { .type = NLA_U32 }, 696 [TCA_U32_HASH] = { .type = NLA_U32 }, 697 [TCA_U32_LINK] = { .type = NLA_U32 }, 698 [TCA_U32_DIVISOR] = { .type = NLA_U32 }, 699 [TCA_U32_SEL] = { .len = sizeof(struct tc_u32_sel) }, 700 [TCA_U32_INDEV] = { .type = NLA_STRING, .len = IFNAMSIZ }, 701 [TCA_U32_MARK] = { .len = sizeof(struct tc_u32_mark) }, 702 [TCA_U32_FLAGS] = { .type = NLA_U32 }, 703 }; 704 705 static int u32_set_parms(struct net *net, struct tcf_proto *tp, 706 unsigned long base, struct tc_u_hnode *ht, 707 struct tc_u_knode *n, struct nlattr **tb, 708 struct nlattr *est, bool ovr) 709 { 710 int err; 711 struct tcf_exts e; 712 713 tcf_exts_init(&e, TCA_U32_ACT, TCA_U32_POLICE); 714 err = tcf_exts_validate(net, tp, tb, est, &e, ovr); 715 if (err < 0) 716 return err; 717 718 err = -EINVAL; 719 if (tb[TCA_U32_LINK]) { 720 u32 handle = nla_get_u32(tb[TCA_U32_LINK]); 721 struct tc_u_hnode *ht_down = NULL, *ht_old; 722 723 if (TC_U32_KEY(handle)) 724 goto errout; 725 726 if (handle) { 727 ht_down = u32_lookup_ht(ht->tp_c, handle); 728 729 if (ht_down == NULL) 730 goto errout; 731 ht_down->refcnt++; 732 } 733 734 ht_old = rtnl_dereference(n->ht_down); 735 rcu_assign_pointer(n->ht_down, ht_down); 736 737 if (ht_old) 738 ht_old->refcnt--; 739 } 740 if (tb[TCA_U32_CLASSID]) { 741 n->res.classid = nla_get_u32(tb[TCA_U32_CLASSID]); 742 tcf_bind_filter(tp, &n->res, base); 743 } 744 745 #ifdef CONFIG_NET_CLS_IND 746 if (tb[TCA_U32_INDEV]) { 747 int ret; 748 ret = tcf_change_indev(net, tb[TCA_U32_INDEV]); 749 if (ret < 0) 750 goto errout; 751 n->ifindex = ret; 752 } 753 #endif 754 tcf_exts_change(tp, &n->exts, &e); 755 756 return 0; 757 errout: 758 tcf_exts_destroy(&e); 759 return err; 760 } 761 762 static void u32_replace_knode(struct tcf_proto *tp, 763 struct tc_u_common *tp_c, 764 struct tc_u_knode *n) 765 { 766 struct tc_u_knode __rcu **ins; 767 struct tc_u_knode *pins; 768 struct tc_u_hnode *ht; 769 770 if (TC_U32_HTID(n->handle) == TC_U32_ROOT) 771 ht = rtnl_dereference(tp->root); 772 else 773 ht = u32_lookup_ht(tp_c, TC_U32_HTID(n->handle)); 774 775 ins = &ht->ht[TC_U32_HASH(n->handle)]; 776 777 /* The node must always exist for it to be replaced if this is not the 778 * case then something went very wrong elsewhere. 779 */ 780 for (pins = rtnl_dereference(*ins); ; 781 ins = &pins->next, pins = rtnl_dereference(*ins)) 782 if (pins->handle == n->handle) 783 break; 784 785 RCU_INIT_POINTER(n->next, pins->next); 786 rcu_assign_pointer(*ins, n); 787 } 788 789 static struct tc_u_knode *u32_init_knode(struct tcf_proto *tp, 790 struct tc_u_knode *n) 791 { 792 struct tc_u_knode *new; 793 struct tc_u32_sel *s = &n->sel; 794 795 new = kzalloc(sizeof(*n) + s->nkeys*sizeof(struct tc_u32_key), 796 GFP_KERNEL); 797 798 if (!new) 799 return NULL; 800 801 RCU_INIT_POINTER(new->next, n->next); 802 new->handle = n->handle; 803 RCU_INIT_POINTER(new->ht_up, n->ht_up); 804 805 #ifdef CONFIG_NET_CLS_IND 806 new->ifindex = n->ifindex; 807 #endif 808 new->fshift = n->fshift; 809 new->res = n->res; 810 new->flags = n->flags; 811 RCU_INIT_POINTER(new->ht_down, n->ht_down); 812 813 /* bump reference count as long as we hold pointer to structure */ 814 if (new->ht_down) 815 new->ht_down->refcnt++; 816 817 #ifdef CONFIG_CLS_U32_PERF 818 /* Statistics may be incremented by readers during update 819 * so we must keep them in tact. When the node is later destroyed 820 * a special destroy call must be made to not free the pf memory. 821 */ 822 new->pf = n->pf; 823 #endif 824 825 #ifdef CONFIG_CLS_U32_MARK 826 new->val = n->val; 827 new->mask = n->mask; 828 /* Similarly success statistics must be moved as pointers */ 829 new->pcpu_success = n->pcpu_success; 830 #endif 831 new->tp = tp; 832 memcpy(&new->sel, s, sizeof(*s) + s->nkeys*sizeof(struct tc_u32_key)); 833 834 tcf_exts_init(&new->exts, TCA_U32_ACT, TCA_U32_POLICE); 835 836 return new; 837 } 838 839 static int u32_change(struct net *net, struct sk_buff *in_skb, 840 struct tcf_proto *tp, unsigned long base, u32 handle, 841 struct nlattr **tca, 842 unsigned long *arg, bool ovr) 843 { 844 struct tc_u_common *tp_c = tp->data; 845 struct tc_u_hnode *ht; 846 struct tc_u_knode *n; 847 struct tc_u32_sel *s; 848 struct nlattr *opt = tca[TCA_OPTIONS]; 849 struct nlattr *tb[TCA_U32_MAX + 1]; 850 u32 htid, flags = 0; 851 int err; 852 #ifdef CONFIG_CLS_U32_PERF 853 size_t size; 854 #endif 855 856 if (opt == NULL) 857 return handle ? -EINVAL : 0; 858 859 err = nla_parse_nested(tb, TCA_U32_MAX, opt, u32_policy); 860 if (err < 0) 861 return err; 862 863 if (tb[TCA_U32_FLAGS]) { 864 flags = nla_get_u32(tb[TCA_U32_FLAGS]); 865 if (!tc_flags_valid(flags)) 866 return err; 867 } 868 869 n = (struct tc_u_knode *)*arg; 870 if (n) { 871 struct tc_u_knode *new; 872 873 if (TC_U32_KEY(n->handle) == 0) 874 return -EINVAL; 875 876 if (n->flags != flags) 877 return -EINVAL; 878 879 new = u32_init_knode(tp, n); 880 if (!new) 881 return -ENOMEM; 882 883 err = u32_set_parms(net, tp, base, 884 rtnl_dereference(n->ht_up), new, tb, 885 tca[TCA_RATE], ovr); 886 887 if (err) { 888 u32_destroy_key(tp, new, false); 889 return err; 890 } 891 892 err = u32_replace_hw_knode(tp, new, flags); 893 if (err) { 894 u32_destroy_key(tp, new, false); 895 return err; 896 } 897 898 u32_replace_knode(tp, tp_c, new); 899 tcf_unbind_filter(tp, &n->res); 900 call_rcu(&n->rcu, u32_delete_key_rcu); 901 return 0; 902 } 903 904 if (tb[TCA_U32_DIVISOR]) { 905 unsigned int divisor = nla_get_u32(tb[TCA_U32_DIVISOR]); 906 907 if (--divisor > 0x100) 908 return -EINVAL; 909 if (TC_U32_KEY(handle)) 910 return -EINVAL; 911 if (handle == 0) { 912 handle = gen_new_htid(tp->data); 913 if (handle == 0) 914 return -ENOMEM; 915 } 916 ht = kzalloc(sizeof(*ht) + divisor*sizeof(void *), GFP_KERNEL); 917 if (ht == NULL) 918 return -ENOBUFS; 919 ht->tp_c = tp_c; 920 ht->refcnt = 1; 921 ht->divisor = divisor; 922 ht->handle = handle; 923 ht->prio = tp->prio; 924 RCU_INIT_POINTER(ht->next, tp_c->hlist); 925 rcu_assign_pointer(tp_c->hlist, ht); 926 *arg = (unsigned long)ht; 927 928 u32_replace_hw_hnode(tp, ht, flags); 929 return 0; 930 } 931 932 if (tb[TCA_U32_HASH]) { 933 htid = nla_get_u32(tb[TCA_U32_HASH]); 934 if (TC_U32_HTID(htid) == TC_U32_ROOT) { 935 ht = rtnl_dereference(tp->root); 936 htid = ht->handle; 937 } else { 938 ht = u32_lookup_ht(tp->data, TC_U32_HTID(htid)); 939 if (ht == NULL) 940 return -EINVAL; 941 } 942 } else { 943 ht = rtnl_dereference(tp->root); 944 htid = ht->handle; 945 } 946 947 if (ht->divisor < TC_U32_HASH(htid)) 948 return -EINVAL; 949 950 if (handle) { 951 if (TC_U32_HTID(handle) && TC_U32_HTID(handle^htid)) 952 return -EINVAL; 953 handle = htid | TC_U32_NODE(handle); 954 } else 955 handle = gen_new_kid(ht, htid); 956 957 if (tb[TCA_U32_SEL] == NULL) 958 return -EINVAL; 959 960 s = nla_data(tb[TCA_U32_SEL]); 961 962 n = kzalloc(sizeof(*n) + s->nkeys*sizeof(struct tc_u32_key), GFP_KERNEL); 963 if (n == NULL) 964 return -ENOBUFS; 965 966 #ifdef CONFIG_CLS_U32_PERF 967 size = sizeof(struct tc_u32_pcnt) + s->nkeys * sizeof(u64); 968 n->pf = __alloc_percpu(size, __alignof__(struct tc_u32_pcnt)); 969 if (!n->pf) { 970 kfree(n); 971 return -ENOBUFS; 972 } 973 #endif 974 975 memcpy(&n->sel, s, sizeof(*s) + s->nkeys*sizeof(struct tc_u32_key)); 976 RCU_INIT_POINTER(n->ht_up, ht); 977 n->handle = handle; 978 n->fshift = s->hmask ? ffs(ntohl(s->hmask)) - 1 : 0; 979 n->flags = flags; 980 tcf_exts_init(&n->exts, TCA_U32_ACT, TCA_U32_POLICE); 981 n->tp = tp; 982 983 #ifdef CONFIG_CLS_U32_MARK 984 n->pcpu_success = alloc_percpu(u32); 985 if (!n->pcpu_success) { 986 err = -ENOMEM; 987 goto errout; 988 } 989 990 if (tb[TCA_U32_MARK]) { 991 struct tc_u32_mark *mark; 992 993 mark = nla_data(tb[TCA_U32_MARK]); 994 n->val = mark->val; 995 n->mask = mark->mask; 996 } 997 #endif 998 999 err = u32_set_parms(net, tp, base, ht, n, tb, tca[TCA_RATE], ovr); 1000 if (err == 0) { 1001 struct tc_u_knode __rcu **ins; 1002 struct tc_u_knode *pins; 1003 1004 err = u32_replace_hw_knode(tp, n, flags); 1005 if (err) 1006 goto errhw; 1007 1008 ins = &ht->ht[TC_U32_HASH(handle)]; 1009 for (pins = rtnl_dereference(*ins); pins; 1010 ins = &pins->next, pins = rtnl_dereference(*ins)) 1011 if (TC_U32_NODE(handle) < TC_U32_NODE(pins->handle)) 1012 break; 1013 1014 RCU_INIT_POINTER(n->next, pins); 1015 rcu_assign_pointer(*ins, n); 1016 *arg = (unsigned long)n; 1017 return 0; 1018 } 1019 1020 errhw: 1021 #ifdef CONFIG_CLS_U32_MARK 1022 free_percpu(n->pcpu_success); 1023 errout: 1024 #endif 1025 1026 #ifdef CONFIG_CLS_U32_PERF 1027 free_percpu(n->pf); 1028 #endif 1029 kfree(n); 1030 return err; 1031 } 1032 1033 static void u32_walk(struct tcf_proto *tp, struct tcf_walker *arg) 1034 { 1035 struct tc_u_common *tp_c = tp->data; 1036 struct tc_u_hnode *ht; 1037 struct tc_u_knode *n; 1038 unsigned int h; 1039 1040 if (arg->stop) 1041 return; 1042 1043 for (ht = rtnl_dereference(tp_c->hlist); 1044 ht; 1045 ht = rtnl_dereference(ht->next)) { 1046 if (ht->prio != tp->prio) 1047 continue; 1048 if (arg->count >= arg->skip) { 1049 if (arg->fn(tp, (unsigned long)ht, arg) < 0) { 1050 arg->stop = 1; 1051 return; 1052 } 1053 } 1054 arg->count++; 1055 for (h = 0; h <= ht->divisor; h++) { 1056 for (n = rtnl_dereference(ht->ht[h]); 1057 n; 1058 n = rtnl_dereference(n->next)) { 1059 if (arg->count < arg->skip) { 1060 arg->count++; 1061 continue; 1062 } 1063 if (arg->fn(tp, (unsigned long)n, arg) < 0) { 1064 arg->stop = 1; 1065 return; 1066 } 1067 arg->count++; 1068 } 1069 } 1070 } 1071 } 1072 1073 static int u32_dump(struct net *net, struct tcf_proto *tp, unsigned long fh, 1074 struct sk_buff *skb, struct tcmsg *t) 1075 { 1076 struct tc_u_knode *n = (struct tc_u_knode *)fh; 1077 struct tc_u_hnode *ht_up, *ht_down; 1078 struct nlattr *nest; 1079 1080 if (n == NULL) 1081 return skb->len; 1082 1083 t->tcm_handle = n->handle; 1084 1085 nest = nla_nest_start(skb, TCA_OPTIONS); 1086 if (nest == NULL) 1087 goto nla_put_failure; 1088 1089 if (TC_U32_KEY(n->handle) == 0) { 1090 struct tc_u_hnode *ht = (struct tc_u_hnode *)fh; 1091 u32 divisor = ht->divisor + 1; 1092 1093 if (nla_put_u32(skb, TCA_U32_DIVISOR, divisor)) 1094 goto nla_put_failure; 1095 } else { 1096 #ifdef CONFIG_CLS_U32_PERF 1097 struct tc_u32_pcnt *gpf; 1098 int cpu; 1099 #endif 1100 1101 if (nla_put(skb, TCA_U32_SEL, 1102 sizeof(n->sel) + n->sel.nkeys*sizeof(struct tc_u32_key), 1103 &n->sel)) 1104 goto nla_put_failure; 1105 1106 ht_up = rtnl_dereference(n->ht_up); 1107 if (ht_up) { 1108 u32 htid = n->handle & 0xFFFFF000; 1109 if (nla_put_u32(skb, TCA_U32_HASH, htid)) 1110 goto nla_put_failure; 1111 } 1112 if (n->res.classid && 1113 nla_put_u32(skb, TCA_U32_CLASSID, n->res.classid)) 1114 goto nla_put_failure; 1115 1116 ht_down = rtnl_dereference(n->ht_down); 1117 if (ht_down && 1118 nla_put_u32(skb, TCA_U32_LINK, ht_down->handle)) 1119 goto nla_put_failure; 1120 1121 if (n->flags && nla_put_u32(skb, TCA_U32_FLAGS, n->flags)) 1122 goto nla_put_failure; 1123 1124 #ifdef CONFIG_CLS_U32_MARK 1125 if ((n->val || n->mask)) { 1126 struct tc_u32_mark mark = {.val = n->val, 1127 .mask = n->mask, 1128 .success = 0}; 1129 int cpum; 1130 1131 for_each_possible_cpu(cpum) { 1132 __u32 cnt = *per_cpu_ptr(n->pcpu_success, cpum); 1133 1134 mark.success += cnt; 1135 } 1136 1137 if (nla_put(skb, TCA_U32_MARK, sizeof(mark), &mark)) 1138 goto nla_put_failure; 1139 } 1140 #endif 1141 1142 if (tcf_exts_dump(skb, &n->exts) < 0) 1143 goto nla_put_failure; 1144 1145 #ifdef CONFIG_NET_CLS_IND 1146 if (n->ifindex) { 1147 struct net_device *dev; 1148 dev = __dev_get_by_index(net, n->ifindex); 1149 if (dev && nla_put_string(skb, TCA_U32_INDEV, dev->name)) 1150 goto nla_put_failure; 1151 } 1152 #endif 1153 #ifdef CONFIG_CLS_U32_PERF 1154 gpf = kzalloc(sizeof(struct tc_u32_pcnt) + 1155 n->sel.nkeys * sizeof(u64), 1156 GFP_KERNEL); 1157 if (!gpf) 1158 goto nla_put_failure; 1159 1160 for_each_possible_cpu(cpu) { 1161 int i; 1162 struct tc_u32_pcnt *pf = per_cpu_ptr(n->pf, cpu); 1163 1164 gpf->rcnt += pf->rcnt; 1165 gpf->rhit += pf->rhit; 1166 for (i = 0; i < n->sel.nkeys; i++) 1167 gpf->kcnts[i] += pf->kcnts[i]; 1168 } 1169 1170 if (nla_put_64bit(skb, TCA_U32_PCNT, 1171 sizeof(struct tc_u32_pcnt) + 1172 n->sel.nkeys * sizeof(u64), 1173 gpf, TCA_U32_PAD)) { 1174 kfree(gpf); 1175 goto nla_put_failure; 1176 } 1177 kfree(gpf); 1178 #endif 1179 } 1180 1181 nla_nest_end(skb, nest); 1182 1183 if (TC_U32_KEY(n->handle)) 1184 if (tcf_exts_dump_stats(skb, &n->exts) < 0) 1185 goto nla_put_failure; 1186 return skb->len; 1187 1188 nla_put_failure: 1189 nla_nest_cancel(skb, nest); 1190 return -1; 1191 } 1192 1193 static struct tcf_proto_ops cls_u32_ops __read_mostly = { 1194 .kind = "u32", 1195 .classify = u32_classify, 1196 .init = u32_init, 1197 .destroy = u32_destroy, 1198 .get = u32_get, 1199 .change = u32_change, 1200 .delete = u32_delete, 1201 .walk = u32_walk, 1202 .dump = u32_dump, 1203 .owner = THIS_MODULE, 1204 }; 1205 1206 static int __init init_u32(void) 1207 { 1208 pr_info("u32 classifier\n"); 1209 #ifdef CONFIG_CLS_U32_PERF 1210 pr_info(" Performance counters on\n"); 1211 #endif 1212 #ifdef CONFIG_NET_CLS_IND 1213 pr_info(" input device check on\n"); 1214 #endif 1215 #ifdef CONFIG_NET_CLS_ACT 1216 pr_info(" Actions configured\n"); 1217 #endif 1218 return register_tcf_proto_ops(&cls_u32_ops); 1219 } 1220 1221 static void __exit exit_u32(void) 1222 { 1223 unregister_tcf_proto_ops(&cls_u32_ops); 1224 } 1225 1226 module_init(init_u32) 1227 module_exit(exit_u32) 1228 MODULE_LICENSE("GPL"); 1229