1 /* 2 * net/sched/cls_u32.c Ugly (or Universal) 32bit key Packet Classifier. 3 * 4 * This program is free software; you can redistribute it and/or 5 * modify it under the terms of the GNU General Public License 6 * as published by the Free Software Foundation; either version 7 * 2 of the License, or (at your option) any later version. 8 * 9 * Authors: Alexey Kuznetsov, <kuznet@ms2.inr.ac.ru> 10 * 11 * The filters are packed to hash tables of key nodes 12 * with a set of 32bit key/mask pairs at every node. 13 * Nodes reference next level hash tables etc. 14 * 15 * This scheme is the best universal classifier I managed to 16 * invent; it is not super-fast, but it is not slow (provided you 17 * program it correctly), and general enough. And its relative 18 * speed grows as the number of rules becomes larger. 19 * 20 * It seems that it represents the best middle point between 21 * speed and manageability both by human and by machine. 22 * 23 * It is especially useful for link sharing combined with QoS; 24 * pure RSVP doesn't need such a general approach and can use 25 * much simpler (and faster) schemes, sort of cls_rsvp.c. 26 * 27 * JHS: We should remove the CONFIG_NET_CLS_IND from here 28 * eventually when the meta match extension is made available 29 * 30 * nfmark match added by Catalin(ux aka Dino) BOIE <catab at umbrella.ro> 31 */ 32 33 #include <linux/module.h> 34 #include <linux/slab.h> 35 #include <linux/types.h> 36 #include <linux/kernel.h> 37 #include <linux/string.h> 38 #include <linux/errno.h> 39 #include <linux/percpu.h> 40 #include <linux/rtnetlink.h> 41 #include <linux/skbuff.h> 42 #include <linux/bitmap.h> 43 #include <linux/netdevice.h> 44 #include <linux/hash.h> 45 #include <net/netlink.h> 46 #include <net/act_api.h> 47 #include <net/pkt_cls.h> 48 #include <linux/netdevice.h> 49 50 struct tc_u_knode { 51 struct tc_u_knode __rcu *next; 52 u32 handle; 53 struct tc_u_hnode __rcu *ht_up; 54 struct tcf_exts exts; 55 #ifdef CONFIG_NET_CLS_IND 56 int ifindex; 57 #endif 58 u8 fshift; 59 struct tcf_result res; 60 struct tc_u_hnode __rcu *ht_down; 61 #ifdef CONFIG_CLS_U32_PERF 62 struct tc_u32_pcnt __percpu *pf; 63 #endif 64 u32 flags; 65 #ifdef CONFIG_CLS_U32_MARK 66 u32 val; 67 u32 mask; 68 u32 __percpu *pcpu_success; 69 #endif 70 struct tcf_proto *tp; 71 union { 72 struct work_struct work; 73 struct rcu_head rcu; 74 }; 75 /* The 'sel' field MUST be the last field in structure to allow for 76 * tc_u32_keys allocated at end of structure. 77 */ 78 struct tc_u32_sel sel; 79 }; 80 81 struct tc_u_hnode { 82 struct tc_u_hnode __rcu *next; 83 u32 handle; 84 u32 prio; 85 struct tc_u_common *tp_c; 86 int refcnt; 87 unsigned int divisor; 88 struct rcu_head rcu; 89 /* The 'ht' field MUST be the last field in structure to allow for 90 * more entries allocated at end of structure. 91 */ 92 struct tc_u_knode __rcu *ht[1]; 93 }; 94 95 struct tc_u_common { 96 struct tc_u_hnode __rcu *hlist; 97 struct Qdisc *q; 98 int refcnt; 99 u32 hgenerator; 100 struct hlist_node hnode; 101 struct rcu_head rcu; 102 }; 103 104 static inline unsigned int u32_hash_fold(__be32 key, 105 const struct tc_u32_sel *sel, 106 u8 fshift) 107 { 108 unsigned int h = ntohl(key & sel->hmask) >> fshift; 109 110 return h; 111 } 112 113 static int u32_classify(struct sk_buff *skb, const struct tcf_proto *tp, 114 struct tcf_result *res) 115 { 116 struct { 117 struct tc_u_knode *knode; 118 unsigned int off; 119 } stack[TC_U32_MAXDEPTH]; 120 121 struct tc_u_hnode *ht = rcu_dereference_bh(tp->root); 122 unsigned int off = skb_network_offset(skb); 123 struct tc_u_knode *n; 124 int sdepth = 0; 125 int off2 = 0; 126 int sel = 0; 127 #ifdef CONFIG_CLS_U32_PERF 128 int j; 129 #endif 130 int i, r; 131 132 next_ht: 133 n = rcu_dereference_bh(ht->ht[sel]); 134 135 next_knode: 136 if (n) { 137 struct tc_u32_key *key = n->sel.keys; 138 139 #ifdef CONFIG_CLS_U32_PERF 140 __this_cpu_inc(n->pf->rcnt); 141 j = 0; 142 #endif 143 144 if (tc_skip_sw(n->flags)) { 145 n = rcu_dereference_bh(n->next); 146 goto next_knode; 147 } 148 149 #ifdef CONFIG_CLS_U32_MARK 150 if ((skb->mark & n->mask) != n->val) { 151 n = rcu_dereference_bh(n->next); 152 goto next_knode; 153 } else { 154 __this_cpu_inc(*n->pcpu_success); 155 } 156 #endif 157 158 for (i = n->sel.nkeys; i > 0; i--, key++) { 159 int toff = off + key->off + (off2 & key->offmask); 160 __be32 *data, hdata; 161 162 if (skb_headroom(skb) + toff > INT_MAX) 163 goto out; 164 165 data = skb_header_pointer(skb, toff, 4, &hdata); 166 if (!data) 167 goto out; 168 if ((*data ^ key->val) & key->mask) { 169 n = rcu_dereference_bh(n->next); 170 goto next_knode; 171 } 172 #ifdef CONFIG_CLS_U32_PERF 173 __this_cpu_inc(n->pf->kcnts[j]); 174 j++; 175 #endif 176 } 177 178 ht = rcu_dereference_bh(n->ht_down); 179 if (!ht) { 180 check_terminal: 181 if (n->sel.flags & TC_U32_TERMINAL) { 182 183 *res = n->res; 184 #ifdef CONFIG_NET_CLS_IND 185 if (!tcf_match_indev(skb, n->ifindex)) { 186 n = rcu_dereference_bh(n->next); 187 goto next_knode; 188 } 189 #endif 190 #ifdef CONFIG_CLS_U32_PERF 191 __this_cpu_inc(n->pf->rhit); 192 #endif 193 r = tcf_exts_exec(skb, &n->exts, res); 194 if (r < 0) { 195 n = rcu_dereference_bh(n->next); 196 goto next_knode; 197 } 198 199 return r; 200 } 201 n = rcu_dereference_bh(n->next); 202 goto next_knode; 203 } 204 205 /* PUSH */ 206 if (sdepth >= TC_U32_MAXDEPTH) 207 goto deadloop; 208 stack[sdepth].knode = n; 209 stack[sdepth].off = off; 210 sdepth++; 211 212 ht = rcu_dereference_bh(n->ht_down); 213 sel = 0; 214 if (ht->divisor) { 215 __be32 *data, hdata; 216 217 data = skb_header_pointer(skb, off + n->sel.hoff, 4, 218 &hdata); 219 if (!data) 220 goto out; 221 sel = ht->divisor & u32_hash_fold(*data, &n->sel, 222 n->fshift); 223 } 224 if (!(n->sel.flags & (TC_U32_VAROFFSET | TC_U32_OFFSET | TC_U32_EAT))) 225 goto next_ht; 226 227 if (n->sel.flags & (TC_U32_OFFSET | TC_U32_VAROFFSET)) { 228 off2 = n->sel.off + 3; 229 if (n->sel.flags & TC_U32_VAROFFSET) { 230 __be16 *data, hdata; 231 232 data = skb_header_pointer(skb, 233 off + n->sel.offoff, 234 2, &hdata); 235 if (!data) 236 goto out; 237 off2 += ntohs(n->sel.offmask & *data) >> 238 n->sel.offshift; 239 } 240 off2 &= ~3; 241 } 242 if (n->sel.flags & TC_U32_EAT) { 243 off += off2; 244 off2 = 0; 245 } 246 247 if (off < skb->len) 248 goto next_ht; 249 } 250 251 /* POP */ 252 if (sdepth--) { 253 n = stack[sdepth].knode; 254 ht = rcu_dereference_bh(n->ht_up); 255 off = stack[sdepth].off; 256 goto check_terminal; 257 } 258 out: 259 return -1; 260 261 deadloop: 262 net_warn_ratelimited("cls_u32: dead loop\n"); 263 return -1; 264 } 265 266 static struct tc_u_hnode *u32_lookup_ht(struct tc_u_common *tp_c, u32 handle) 267 { 268 struct tc_u_hnode *ht; 269 270 for (ht = rtnl_dereference(tp_c->hlist); 271 ht; 272 ht = rtnl_dereference(ht->next)) 273 if (ht->handle == handle) 274 break; 275 276 return ht; 277 } 278 279 static struct tc_u_knode *u32_lookup_key(struct tc_u_hnode *ht, u32 handle) 280 { 281 unsigned int sel; 282 struct tc_u_knode *n = NULL; 283 284 sel = TC_U32_HASH(handle); 285 if (sel > ht->divisor) 286 goto out; 287 288 for (n = rtnl_dereference(ht->ht[sel]); 289 n; 290 n = rtnl_dereference(n->next)) 291 if (n->handle == handle) 292 break; 293 out: 294 return n; 295 } 296 297 298 static void *u32_get(struct tcf_proto *tp, u32 handle) 299 { 300 struct tc_u_hnode *ht; 301 struct tc_u_common *tp_c = tp->data; 302 303 if (TC_U32_HTID(handle) == TC_U32_ROOT) 304 ht = rtnl_dereference(tp->root); 305 else 306 ht = u32_lookup_ht(tp_c, TC_U32_HTID(handle)); 307 308 if (!ht) 309 return NULL; 310 311 if (TC_U32_KEY(handle) == 0) 312 return ht; 313 314 return u32_lookup_key(ht, handle); 315 } 316 317 static u32 gen_new_htid(struct tc_u_common *tp_c) 318 { 319 int i = 0x800; 320 321 /* hgenerator only used inside rtnl lock it is safe to increment 322 * without read _copy_ update semantics 323 */ 324 do { 325 if (++tp_c->hgenerator == 0x7FF) 326 tp_c->hgenerator = 1; 327 } while (--i > 0 && u32_lookup_ht(tp_c, (tp_c->hgenerator|0x800)<<20)); 328 329 return i > 0 ? (tp_c->hgenerator|0x800)<<20 : 0; 330 } 331 332 static struct hlist_head *tc_u_common_hash; 333 334 #define U32_HASH_SHIFT 10 335 #define U32_HASH_SIZE (1 << U32_HASH_SHIFT) 336 337 static unsigned int tc_u_hash(const struct tcf_proto *tp) 338 { 339 struct net_device *dev = tp->q->dev_queue->dev; 340 u32 qhandle = tp->q->handle; 341 int ifindex = dev->ifindex; 342 343 return hash_64((u64)ifindex << 32 | qhandle, U32_HASH_SHIFT); 344 } 345 346 static struct tc_u_common *tc_u_common_find(const struct tcf_proto *tp) 347 { 348 struct tc_u_common *tc; 349 unsigned int h; 350 351 h = tc_u_hash(tp); 352 hlist_for_each_entry(tc, &tc_u_common_hash[h], hnode) { 353 if (tc->q == tp->q) 354 return tc; 355 } 356 return NULL; 357 } 358 359 static int u32_init(struct tcf_proto *tp) 360 { 361 struct tc_u_hnode *root_ht; 362 struct tc_u_common *tp_c; 363 unsigned int h; 364 365 tp_c = tc_u_common_find(tp); 366 367 root_ht = kzalloc(sizeof(*root_ht), GFP_KERNEL); 368 if (root_ht == NULL) 369 return -ENOBUFS; 370 371 root_ht->refcnt++; 372 root_ht->handle = tp_c ? gen_new_htid(tp_c) : 0x80000000; 373 root_ht->prio = tp->prio; 374 375 if (tp_c == NULL) { 376 tp_c = kzalloc(sizeof(*tp_c), GFP_KERNEL); 377 if (tp_c == NULL) { 378 kfree(root_ht); 379 return -ENOBUFS; 380 } 381 tp_c->q = tp->q; 382 INIT_HLIST_NODE(&tp_c->hnode); 383 384 h = tc_u_hash(tp); 385 hlist_add_head(&tp_c->hnode, &tc_u_common_hash[h]); 386 } 387 388 tp_c->refcnt++; 389 RCU_INIT_POINTER(root_ht->next, tp_c->hlist); 390 rcu_assign_pointer(tp_c->hlist, root_ht); 391 root_ht->tp_c = tp_c; 392 393 rcu_assign_pointer(tp->root, root_ht); 394 tp->data = tp_c; 395 return 0; 396 } 397 398 static int u32_destroy_key(struct tcf_proto *tp, struct tc_u_knode *n, 399 bool free_pf) 400 { 401 tcf_exts_destroy(&n->exts); 402 tcf_exts_put_net(&n->exts); 403 if (n->ht_down) 404 n->ht_down->refcnt--; 405 #ifdef CONFIG_CLS_U32_PERF 406 if (free_pf) 407 free_percpu(n->pf); 408 #endif 409 #ifdef CONFIG_CLS_U32_MARK 410 if (free_pf) 411 free_percpu(n->pcpu_success); 412 #endif 413 kfree(n); 414 return 0; 415 } 416 417 /* u32_delete_key_rcu should be called when free'ing a copied 418 * version of a tc_u_knode obtained from u32_init_knode(). When 419 * copies are obtained from u32_init_knode() the statistics are 420 * shared between the old and new copies to allow readers to 421 * continue to update the statistics during the copy. To support 422 * this the u32_delete_key_rcu variant does not free the percpu 423 * statistics. 424 */ 425 static void u32_delete_key_work(struct work_struct *work) 426 { 427 struct tc_u_knode *key = container_of(work, struct tc_u_knode, work); 428 429 rtnl_lock(); 430 u32_destroy_key(key->tp, key, false); 431 rtnl_unlock(); 432 } 433 434 static void u32_delete_key_rcu(struct rcu_head *rcu) 435 { 436 struct tc_u_knode *key = container_of(rcu, struct tc_u_knode, rcu); 437 438 INIT_WORK(&key->work, u32_delete_key_work); 439 tcf_queue_work(&key->work); 440 } 441 442 /* u32_delete_key_freepf_rcu is the rcu callback variant 443 * that free's the entire structure including the statistics 444 * percpu variables. Only use this if the key is not a copy 445 * returned by u32_init_knode(). See u32_delete_key_rcu() 446 * for the variant that should be used with keys return from 447 * u32_init_knode() 448 */ 449 static void u32_delete_key_freepf_work(struct work_struct *work) 450 { 451 struct tc_u_knode *key = container_of(work, struct tc_u_knode, work); 452 453 rtnl_lock(); 454 u32_destroy_key(key->tp, key, true); 455 rtnl_unlock(); 456 } 457 458 static void u32_delete_key_freepf_rcu(struct rcu_head *rcu) 459 { 460 struct tc_u_knode *key = container_of(rcu, struct tc_u_knode, rcu); 461 462 INIT_WORK(&key->work, u32_delete_key_freepf_work); 463 tcf_queue_work(&key->work); 464 } 465 466 static int u32_delete_key(struct tcf_proto *tp, struct tc_u_knode *key) 467 { 468 struct tc_u_knode __rcu **kp; 469 struct tc_u_knode *pkp; 470 struct tc_u_hnode *ht = rtnl_dereference(key->ht_up); 471 472 if (ht) { 473 kp = &ht->ht[TC_U32_HASH(key->handle)]; 474 for (pkp = rtnl_dereference(*kp); pkp; 475 kp = &pkp->next, pkp = rtnl_dereference(*kp)) { 476 if (pkp == key) { 477 RCU_INIT_POINTER(*kp, key->next); 478 479 tcf_unbind_filter(tp, &key->res); 480 tcf_exts_get_net(&key->exts); 481 call_rcu(&key->rcu, u32_delete_key_freepf_rcu); 482 return 0; 483 } 484 } 485 } 486 WARN_ON(1); 487 return 0; 488 } 489 490 static void u32_remove_hw_knode(struct tcf_proto *tp, u32 handle) 491 { 492 struct net_device *dev = tp->q->dev_queue->dev; 493 struct tc_cls_u32_offload cls_u32 = {}; 494 495 if (!tc_should_offload(dev, 0)) 496 return; 497 498 tc_cls_common_offload_init(&cls_u32.common, tp); 499 cls_u32.command = TC_CLSU32_DELETE_KNODE; 500 cls_u32.knode.handle = handle; 501 502 dev->netdev_ops->ndo_setup_tc(dev, TC_SETUP_CLSU32, &cls_u32); 503 } 504 505 static int u32_replace_hw_hnode(struct tcf_proto *tp, struct tc_u_hnode *h, 506 u32 flags) 507 { 508 struct net_device *dev = tp->q->dev_queue->dev; 509 struct tc_cls_u32_offload cls_u32 = {}; 510 int err; 511 512 if (!tc_should_offload(dev, flags)) 513 return tc_skip_sw(flags) ? -EINVAL : 0; 514 515 tc_cls_common_offload_init(&cls_u32.common, tp); 516 cls_u32.command = TC_CLSU32_NEW_HNODE; 517 cls_u32.hnode.divisor = h->divisor; 518 cls_u32.hnode.handle = h->handle; 519 cls_u32.hnode.prio = h->prio; 520 521 err = dev->netdev_ops->ndo_setup_tc(dev, TC_SETUP_CLSU32, &cls_u32); 522 if (tc_skip_sw(flags)) 523 return err; 524 525 return 0; 526 } 527 528 static void u32_clear_hw_hnode(struct tcf_proto *tp, struct tc_u_hnode *h) 529 { 530 struct net_device *dev = tp->q->dev_queue->dev; 531 struct tc_cls_u32_offload cls_u32 = {}; 532 533 if (!tc_should_offload(dev, 0)) 534 return; 535 536 tc_cls_common_offload_init(&cls_u32.common, tp); 537 cls_u32.command = TC_CLSU32_DELETE_HNODE; 538 cls_u32.hnode.divisor = h->divisor; 539 cls_u32.hnode.handle = h->handle; 540 cls_u32.hnode.prio = h->prio; 541 542 dev->netdev_ops->ndo_setup_tc(dev, TC_SETUP_CLSU32, &cls_u32); 543 } 544 545 static int u32_replace_hw_knode(struct tcf_proto *tp, struct tc_u_knode *n, 546 u32 flags) 547 { 548 struct net_device *dev = tp->q->dev_queue->dev; 549 struct tc_cls_u32_offload cls_u32 = {}; 550 int err; 551 552 if (!tc_should_offload(dev, flags)) 553 return tc_skip_sw(flags) ? -EINVAL : 0; 554 555 tc_cls_common_offload_init(&cls_u32.common, tp); 556 cls_u32.command = TC_CLSU32_REPLACE_KNODE; 557 cls_u32.knode.handle = n->handle; 558 cls_u32.knode.fshift = n->fshift; 559 #ifdef CONFIG_CLS_U32_MARK 560 cls_u32.knode.val = n->val; 561 cls_u32.knode.mask = n->mask; 562 #else 563 cls_u32.knode.val = 0; 564 cls_u32.knode.mask = 0; 565 #endif 566 cls_u32.knode.sel = &n->sel; 567 cls_u32.knode.exts = &n->exts; 568 if (n->ht_down) 569 cls_u32.knode.link_handle = n->ht_down->handle; 570 571 err = dev->netdev_ops->ndo_setup_tc(dev, TC_SETUP_CLSU32, &cls_u32); 572 573 if (!err) 574 n->flags |= TCA_CLS_FLAGS_IN_HW; 575 576 if (tc_skip_sw(flags)) 577 return err; 578 579 return 0; 580 } 581 582 static void u32_clear_hnode(struct tcf_proto *tp, struct tc_u_hnode *ht) 583 { 584 struct tc_u_knode *n; 585 unsigned int h; 586 587 for (h = 0; h <= ht->divisor; h++) { 588 while ((n = rtnl_dereference(ht->ht[h])) != NULL) { 589 RCU_INIT_POINTER(ht->ht[h], 590 rtnl_dereference(n->next)); 591 tcf_unbind_filter(tp, &n->res); 592 u32_remove_hw_knode(tp, n->handle); 593 if (tcf_exts_get_net(&n->exts)) 594 call_rcu(&n->rcu, u32_delete_key_freepf_rcu); 595 else 596 u32_destroy_key(n->tp, n, true); 597 } 598 } 599 } 600 601 static int u32_destroy_hnode(struct tcf_proto *tp, struct tc_u_hnode *ht) 602 { 603 struct tc_u_common *tp_c = tp->data; 604 struct tc_u_hnode __rcu **hn; 605 struct tc_u_hnode *phn; 606 607 WARN_ON(ht->refcnt); 608 609 u32_clear_hnode(tp, ht); 610 611 hn = &tp_c->hlist; 612 for (phn = rtnl_dereference(*hn); 613 phn; 614 hn = &phn->next, phn = rtnl_dereference(*hn)) { 615 if (phn == ht) { 616 u32_clear_hw_hnode(tp, ht); 617 RCU_INIT_POINTER(*hn, ht->next); 618 kfree_rcu(ht, rcu); 619 return 0; 620 } 621 } 622 623 return -ENOENT; 624 } 625 626 static bool ht_empty(struct tc_u_hnode *ht) 627 { 628 unsigned int h; 629 630 for (h = 0; h <= ht->divisor; h++) 631 if (rcu_access_pointer(ht->ht[h])) 632 return false; 633 634 return true; 635 } 636 637 static void u32_destroy(struct tcf_proto *tp) 638 { 639 struct tc_u_common *tp_c = tp->data; 640 struct tc_u_hnode *root_ht = rtnl_dereference(tp->root); 641 642 WARN_ON(root_ht == NULL); 643 644 if (root_ht && --root_ht->refcnt == 0) 645 u32_destroy_hnode(tp, root_ht); 646 647 if (--tp_c->refcnt == 0) { 648 struct tc_u_hnode *ht; 649 650 hlist_del(&tp_c->hnode); 651 652 for (ht = rtnl_dereference(tp_c->hlist); 653 ht; 654 ht = rtnl_dereference(ht->next)) { 655 ht->refcnt--; 656 u32_clear_hnode(tp, ht); 657 } 658 659 while ((ht = rtnl_dereference(tp_c->hlist)) != NULL) { 660 RCU_INIT_POINTER(tp_c->hlist, ht->next); 661 kfree_rcu(ht, rcu); 662 } 663 664 kfree(tp_c); 665 } 666 667 tp->data = NULL; 668 } 669 670 static int u32_delete(struct tcf_proto *tp, void *arg, bool *last) 671 { 672 struct tc_u_hnode *ht = arg; 673 struct tc_u_hnode *root_ht = rtnl_dereference(tp->root); 674 struct tc_u_common *tp_c = tp->data; 675 int ret = 0; 676 677 if (ht == NULL) 678 goto out; 679 680 if (TC_U32_KEY(ht->handle)) { 681 u32_remove_hw_knode(tp, ht->handle); 682 ret = u32_delete_key(tp, (struct tc_u_knode *)ht); 683 goto out; 684 } 685 686 if (root_ht == ht) 687 return -EINVAL; 688 689 if (ht->refcnt == 1) { 690 ht->refcnt--; 691 u32_destroy_hnode(tp, ht); 692 } else { 693 return -EBUSY; 694 } 695 696 out: 697 *last = true; 698 if (root_ht) { 699 if (root_ht->refcnt > 1) { 700 *last = false; 701 goto ret; 702 } 703 if (root_ht->refcnt == 1) { 704 if (!ht_empty(root_ht)) { 705 *last = false; 706 goto ret; 707 } 708 } 709 } 710 711 if (tp_c->refcnt > 1) { 712 *last = false; 713 goto ret; 714 } 715 716 if (tp_c->refcnt == 1) { 717 struct tc_u_hnode *ht; 718 719 for (ht = rtnl_dereference(tp_c->hlist); 720 ht; 721 ht = rtnl_dereference(ht->next)) 722 if (!ht_empty(ht)) { 723 *last = false; 724 break; 725 } 726 } 727 728 ret: 729 return ret; 730 } 731 732 #define NR_U32_NODE (1<<12) 733 static u32 gen_new_kid(struct tc_u_hnode *ht, u32 handle) 734 { 735 struct tc_u_knode *n; 736 unsigned long i; 737 unsigned long *bitmap = kzalloc(BITS_TO_LONGS(NR_U32_NODE) * sizeof(unsigned long), 738 GFP_KERNEL); 739 if (!bitmap) 740 return handle | 0xFFF; 741 742 for (n = rtnl_dereference(ht->ht[TC_U32_HASH(handle)]); 743 n; 744 n = rtnl_dereference(n->next)) 745 set_bit(TC_U32_NODE(n->handle), bitmap); 746 747 i = find_next_zero_bit(bitmap, NR_U32_NODE, 0x800); 748 if (i >= NR_U32_NODE) 749 i = find_next_zero_bit(bitmap, NR_U32_NODE, 1); 750 751 kfree(bitmap); 752 return handle | (i >= NR_U32_NODE ? 0xFFF : i); 753 } 754 755 static const struct nla_policy u32_policy[TCA_U32_MAX + 1] = { 756 [TCA_U32_CLASSID] = { .type = NLA_U32 }, 757 [TCA_U32_HASH] = { .type = NLA_U32 }, 758 [TCA_U32_LINK] = { .type = NLA_U32 }, 759 [TCA_U32_DIVISOR] = { .type = NLA_U32 }, 760 [TCA_U32_SEL] = { .len = sizeof(struct tc_u32_sel) }, 761 [TCA_U32_INDEV] = { .type = NLA_STRING, .len = IFNAMSIZ }, 762 [TCA_U32_MARK] = { .len = sizeof(struct tc_u32_mark) }, 763 [TCA_U32_FLAGS] = { .type = NLA_U32 }, 764 }; 765 766 static int u32_set_parms(struct net *net, struct tcf_proto *tp, 767 unsigned long base, struct tc_u_hnode *ht, 768 struct tc_u_knode *n, struct nlattr **tb, 769 struct nlattr *est, bool ovr) 770 { 771 int err; 772 773 err = tcf_exts_validate(net, tp, tb, est, &n->exts, ovr); 774 if (err < 0) 775 return err; 776 777 if (tb[TCA_U32_LINK]) { 778 u32 handle = nla_get_u32(tb[TCA_U32_LINK]); 779 struct tc_u_hnode *ht_down = NULL, *ht_old; 780 781 if (TC_U32_KEY(handle)) 782 return -EINVAL; 783 784 if (handle) { 785 ht_down = u32_lookup_ht(ht->tp_c, handle); 786 787 if (ht_down == NULL) 788 return -EINVAL; 789 ht_down->refcnt++; 790 } 791 792 ht_old = rtnl_dereference(n->ht_down); 793 rcu_assign_pointer(n->ht_down, ht_down); 794 795 if (ht_old) 796 ht_old->refcnt--; 797 } 798 if (tb[TCA_U32_CLASSID]) { 799 n->res.classid = nla_get_u32(tb[TCA_U32_CLASSID]); 800 tcf_bind_filter(tp, &n->res, base); 801 } 802 803 #ifdef CONFIG_NET_CLS_IND 804 if (tb[TCA_U32_INDEV]) { 805 int ret; 806 ret = tcf_change_indev(net, tb[TCA_U32_INDEV]); 807 if (ret < 0) 808 return -EINVAL; 809 n->ifindex = ret; 810 } 811 #endif 812 return 0; 813 } 814 815 static void u32_replace_knode(struct tcf_proto *tp, struct tc_u_common *tp_c, 816 struct tc_u_knode *n) 817 { 818 struct tc_u_knode __rcu **ins; 819 struct tc_u_knode *pins; 820 struct tc_u_hnode *ht; 821 822 if (TC_U32_HTID(n->handle) == TC_U32_ROOT) 823 ht = rtnl_dereference(tp->root); 824 else 825 ht = u32_lookup_ht(tp_c, TC_U32_HTID(n->handle)); 826 827 ins = &ht->ht[TC_U32_HASH(n->handle)]; 828 829 /* The node must always exist for it to be replaced if this is not the 830 * case then something went very wrong elsewhere. 831 */ 832 for (pins = rtnl_dereference(*ins); ; 833 ins = &pins->next, pins = rtnl_dereference(*ins)) 834 if (pins->handle == n->handle) 835 break; 836 837 RCU_INIT_POINTER(n->next, pins->next); 838 rcu_assign_pointer(*ins, n); 839 } 840 841 static struct tc_u_knode *u32_init_knode(struct tcf_proto *tp, 842 struct tc_u_knode *n) 843 { 844 struct tc_u_knode *new; 845 struct tc_u32_sel *s = &n->sel; 846 847 new = kzalloc(sizeof(*n) + s->nkeys*sizeof(struct tc_u32_key), 848 GFP_KERNEL); 849 850 if (!new) 851 return NULL; 852 853 RCU_INIT_POINTER(new->next, n->next); 854 new->handle = n->handle; 855 RCU_INIT_POINTER(new->ht_up, n->ht_up); 856 857 #ifdef CONFIG_NET_CLS_IND 858 new->ifindex = n->ifindex; 859 #endif 860 new->fshift = n->fshift; 861 new->res = n->res; 862 new->flags = n->flags; 863 RCU_INIT_POINTER(new->ht_down, n->ht_down); 864 865 /* bump reference count as long as we hold pointer to structure */ 866 if (new->ht_down) 867 new->ht_down->refcnt++; 868 869 #ifdef CONFIG_CLS_U32_PERF 870 /* Statistics may be incremented by readers during update 871 * so we must keep them in tact. When the node is later destroyed 872 * a special destroy call must be made to not free the pf memory. 873 */ 874 new->pf = n->pf; 875 #endif 876 877 #ifdef CONFIG_CLS_U32_MARK 878 new->val = n->val; 879 new->mask = n->mask; 880 /* Similarly success statistics must be moved as pointers */ 881 new->pcpu_success = n->pcpu_success; 882 #endif 883 new->tp = tp; 884 memcpy(&new->sel, s, sizeof(*s) + s->nkeys*sizeof(struct tc_u32_key)); 885 886 if (tcf_exts_init(&new->exts, TCA_U32_ACT, TCA_U32_POLICE)) { 887 kfree(new); 888 return NULL; 889 } 890 891 return new; 892 } 893 894 static int u32_change(struct net *net, struct sk_buff *in_skb, 895 struct tcf_proto *tp, unsigned long base, u32 handle, 896 struct nlattr **tca, void **arg, bool ovr) 897 { 898 struct tc_u_common *tp_c = tp->data; 899 struct tc_u_hnode *ht; 900 struct tc_u_knode *n; 901 struct tc_u32_sel *s; 902 struct nlattr *opt = tca[TCA_OPTIONS]; 903 struct nlattr *tb[TCA_U32_MAX + 1]; 904 u32 htid, flags = 0; 905 int err; 906 #ifdef CONFIG_CLS_U32_PERF 907 size_t size; 908 #endif 909 910 if (opt == NULL) 911 return handle ? -EINVAL : 0; 912 913 err = nla_parse_nested(tb, TCA_U32_MAX, opt, u32_policy, NULL); 914 if (err < 0) 915 return err; 916 917 if (tb[TCA_U32_FLAGS]) { 918 flags = nla_get_u32(tb[TCA_U32_FLAGS]); 919 if (!tc_flags_valid(flags)) 920 return -EINVAL; 921 } 922 923 n = *arg; 924 if (n) { 925 struct tc_u_knode *new; 926 927 if (TC_U32_KEY(n->handle) == 0) 928 return -EINVAL; 929 930 if (n->flags != flags) 931 return -EINVAL; 932 933 new = u32_init_knode(tp, n); 934 if (!new) 935 return -ENOMEM; 936 937 err = u32_set_parms(net, tp, base, 938 rtnl_dereference(n->ht_up), new, tb, 939 tca[TCA_RATE], ovr); 940 941 if (err) { 942 u32_destroy_key(tp, new, false); 943 return err; 944 } 945 946 err = u32_replace_hw_knode(tp, new, flags); 947 if (err) { 948 u32_destroy_key(tp, new, false); 949 return err; 950 } 951 952 if (!tc_in_hw(new->flags)) 953 new->flags |= TCA_CLS_FLAGS_NOT_IN_HW; 954 955 u32_replace_knode(tp, tp_c, new); 956 tcf_unbind_filter(tp, &n->res); 957 tcf_exts_get_net(&n->exts); 958 call_rcu(&n->rcu, u32_delete_key_rcu); 959 return 0; 960 } 961 962 if (tb[TCA_U32_DIVISOR]) { 963 unsigned int divisor = nla_get_u32(tb[TCA_U32_DIVISOR]); 964 965 if (--divisor > 0x100) 966 return -EINVAL; 967 if (TC_U32_KEY(handle)) 968 return -EINVAL; 969 if (handle == 0) { 970 handle = gen_new_htid(tp->data); 971 if (handle == 0) 972 return -ENOMEM; 973 } 974 ht = kzalloc(sizeof(*ht) + divisor*sizeof(void *), GFP_KERNEL); 975 if (ht == NULL) 976 return -ENOBUFS; 977 ht->tp_c = tp_c; 978 ht->refcnt = 1; 979 ht->divisor = divisor; 980 ht->handle = handle; 981 ht->prio = tp->prio; 982 983 err = u32_replace_hw_hnode(tp, ht, flags); 984 if (err) { 985 kfree(ht); 986 return err; 987 } 988 989 RCU_INIT_POINTER(ht->next, tp_c->hlist); 990 rcu_assign_pointer(tp_c->hlist, ht); 991 *arg = ht; 992 993 return 0; 994 } 995 996 if (tb[TCA_U32_HASH]) { 997 htid = nla_get_u32(tb[TCA_U32_HASH]); 998 if (TC_U32_HTID(htid) == TC_U32_ROOT) { 999 ht = rtnl_dereference(tp->root); 1000 htid = ht->handle; 1001 } else { 1002 ht = u32_lookup_ht(tp->data, TC_U32_HTID(htid)); 1003 if (ht == NULL) 1004 return -EINVAL; 1005 } 1006 } else { 1007 ht = rtnl_dereference(tp->root); 1008 htid = ht->handle; 1009 } 1010 1011 if (ht->divisor < TC_U32_HASH(htid)) 1012 return -EINVAL; 1013 1014 if (handle) { 1015 if (TC_U32_HTID(handle) && TC_U32_HTID(handle^htid)) 1016 return -EINVAL; 1017 handle = htid | TC_U32_NODE(handle); 1018 } else 1019 handle = gen_new_kid(ht, htid); 1020 1021 if (tb[TCA_U32_SEL] == NULL) 1022 return -EINVAL; 1023 1024 s = nla_data(tb[TCA_U32_SEL]); 1025 1026 n = kzalloc(sizeof(*n) + s->nkeys*sizeof(struct tc_u32_key), GFP_KERNEL); 1027 if (n == NULL) 1028 return -ENOBUFS; 1029 1030 #ifdef CONFIG_CLS_U32_PERF 1031 size = sizeof(struct tc_u32_pcnt) + s->nkeys * sizeof(u64); 1032 n->pf = __alloc_percpu(size, __alignof__(struct tc_u32_pcnt)); 1033 if (!n->pf) { 1034 kfree(n); 1035 return -ENOBUFS; 1036 } 1037 #endif 1038 1039 memcpy(&n->sel, s, sizeof(*s) + s->nkeys*sizeof(struct tc_u32_key)); 1040 RCU_INIT_POINTER(n->ht_up, ht); 1041 n->handle = handle; 1042 n->fshift = s->hmask ? ffs(ntohl(s->hmask)) - 1 : 0; 1043 n->flags = flags; 1044 n->tp = tp; 1045 1046 err = tcf_exts_init(&n->exts, TCA_U32_ACT, TCA_U32_POLICE); 1047 if (err < 0) 1048 goto errout; 1049 1050 #ifdef CONFIG_CLS_U32_MARK 1051 n->pcpu_success = alloc_percpu(u32); 1052 if (!n->pcpu_success) { 1053 err = -ENOMEM; 1054 goto errout; 1055 } 1056 1057 if (tb[TCA_U32_MARK]) { 1058 struct tc_u32_mark *mark; 1059 1060 mark = nla_data(tb[TCA_U32_MARK]); 1061 n->val = mark->val; 1062 n->mask = mark->mask; 1063 } 1064 #endif 1065 1066 err = u32_set_parms(net, tp, base, ht, n, tb, tca[TCA_RATE], ovr); 1067 if (err == 0) { 1068 struct tc_u_knode __rcu **ins; 1069 struct tc_u_knode *pins; 1070 1071 err = u32_replace_hw_knode(tp, n, flags); 1072 if (err) 1073 goto errhw; 1074 1075 if (!tc_in_hw(n->flags)) 1076 n->flags |= TCA_CLS_FLAGS_NOT_IN_HW; 1077 1078 ins = &ht->ht[TC_U32_HASH(handle)]; 1079 for (pins = rtnl_dereference(*ins); pins; 1080 ins = &pins->next, pins = rtnl_dereference(*ins)) 1081 if (TC_U32_NODE(handle) < TC_U32_NODE(pins->handle)) 1082 break; 1083 1084 RCU_INIT_POINTER(n->next, pins); 1085 rcu_assign_pointer(*ins, n); 1086 *arg = n; 1087 return 0; 1088 } 1089 1090 errhw: 1091 #ifdef CONFIG_CLS_U32_MARK 1092 free_percpu(n->pcpu_success); 1093 #endif 1094 1095 errout: 1096 tcf_exts_destroy(&n->exts); 1097 #ifdef CONFIG_CLS_U32_PERF 1098 free_percpu(n->pf); 1099 #endif 1100 kfree(n); 1101 return err; 1102 } 1103 1104 static void u32_walk(struct tcf_proto *tp, struct tcf_walker *arg) 1105 { 1106 struct tc_u_common *tp_c = tp->data; 1107 struct tc_u_hnode *ht; 1108 struct tc_u_knode *n; 1109 unsigned int h; 1110 1111 if (arg->stop) 1112 return; 1113 1114 for (ht = rtnl_dereference(tp_c->hlist); 1115 ht; 1116 ht = rtnl_dereference(ht->next)) { 1117 if (ht->prio != tp->prio) 1118 continue; 1119 if (arg->count >= arg->skip) { 1120 if (arg->fn(tp, ht, arg) < 0) { 1121 arg->stop = 1; 1122 return; 1123 } 1124 } 1125 arg->count++; 1126 for (h = 0; h <= ht->divisor; h++) { 1127 for (n = rtnl_dereference(ht->ht[h]); 1128 n; 1129 n = rtnl_dereference(n->next)) { 1130 if (arg->count < arg->skip) { 1131 arg->count++; 1132 continue; 1133 } 1134 if (arg->fn(tp, n, arg) < 0) { 1135 arg->stop = 1; 1136 return; 1137 } 1138 arg->count++; 1139 } 1140 } 1141 } 1142 } 1143 1144 static void u32_bind_class(void *fh, u32 classid, unsigned long cl) 1145 { 1146 struct tc_u_knode *n = fh; 1147 1148 if (n && n->res.classid == classid) 1149 n->res.class = cl; 1150 } 1151 1152 static int u32_dump(struct net *net, struct tcf_proto *tp, void *fh, 1153 struct sk_buff *skb, struct tcmsg *t) 1154 { 1155 struct tc_u_knode *n = fh; 1156 struct tc_u_hnode *ht_up, *ht_down; 1157 struct nlattr *nest; 1158 1159 if (n == NULL) 1160 return skb->len; 1161 1162 t->tcm_handle = n->handle; 1163 1164 nest = nla_nest_start(skb, TCA_OPTIONS); 1165 if (nest == NULL) 1166 goto nla_put_failure; 1167 1168 if (TC_U32_KEY(n->handle) == 0) { 1169 struct tc_u_hnode *ht = fh; 1170 u32 divisor = ht->divisor + 1; 1171 1172 if (nla_put_u32(skb, TCA_U32_DIVISOR, divisor)) 1173 goto nla_put_failure; 1174 } else { 1175 #ifdef CONFIG_CLS_U32_PERF 1176 struct tc_u32_pcnt *gpf; 1177 int cpu; 1178 #endif 1179 1180 if (nla_put(skb, TCA_U32_SEL, 1181 sizeof(n->sel) + n->sel.nkeys*sizeof(struct tc_u32_key), 1182 &n->sel)) 1183 goto nla_put_failure; 1184 1185 ht_up = rtnl_dereference(n->ht_up); 1186 if (ht_up) { 1187 u32 htid = n->handle & 0xFFFFF000; 1188 if (nla_put_u32(skb, TCA_U32_HASH, htid)) 1189 goto nla_put_failure; 1190 } 1191 if (n->res.classid && 1192 nla_put_u32(skb, TCA_U32_CLASSID, n->res.classid)) 1193 goto nla_put_failure; 1194 1195 ht_down = rtnl_dereference(n->ht_down); 1196 if (ht_down && 1197 nla_put_u32(skb, TCA_U32_LINK, ht_down->handle)) 1198 goto nla_put_failure; 1199 1200 if (n->flags && nla_put_u32(skb, TCA_U32_FLAGS, n->flags)) 1201 goto nla_put_failure; 1202 1203 #ifdef CONFIG_CLS_U32_MARK 1204 if ((n->val || n->mask)) { 1205 struct tc_u32_mark mark = {.val = n->val, 1206 .mask = n->mask, 1207 .success = 0}; 1208 int cpum; 1209 1210 for_each_possible_cpu(cpum) { 1211 __u32 cnt = *per_cpu_ptr(n->pcpu_success, cpum); 1212 1213 mark.success += cnt; 1214 } 1215 1216 if (nla_put(skb, TCA_U32_MARK, sizeof(mark), &mark)) 1217 goto nla_put_failure; 1218 } 1219 #endif 1220 1221 if (tcf_exts_dump(skb, &n->exts) < 0) 1222 goto nla_put_failure; 1223 1224 #ifdef CONFIG_NET_CLS_IND 1225 if (n->ifindex) { 1226 struct net_device *dev; 1227 dev = __dev_get_by_index(net, n->ifindex); 1228 if (dev && nla_put_string(skb, TCA_U32_INDEV, dev->name)) 1229 goto nla_put_failure; 1230 } 1231 #endif 1232 #ifdef CONFIG_CLS_U32_PERF 1233 gpf = kzalloc(sizeof(struct tc_u32_pcnt) + 1234 n->sel.nkeys * sizeof(u64), 1235 GFP_KERNEL); 1236 if (!gpf) 1237 goto nla_put_failure; 1238 1239 for_each_possible_cpu(cpu) { 1240 int i; 1241 struct tc_u32_pcnt *pf = per_cpu_ptr(n->pf, cpu); 1242 1243 gpf->rcnt += pf->rcnt; 1244 gpf->rhit += pf->rhit; 1245 for (i = 0; i < n->sel.nkeys; i++) 1246 gpf->kcnts[i] += pf->kcnts[i]; 1247 } 1248 1249 if (nla_put_64bit(skb, TCA_U32_PCNT, 1250 sizeof(struct tc_u32_pcnt) + 1251 n->sel.nkeys * sizeof(u64), 1252 gpf, TCA_U32_PAD)) { 1253 kfree(gpf); 1254 goto nla_put_failure; 1255 } 1256 kfree(gpf); 1257 #endif 1258 } 1259 1260 nla_nest_end(skb, nest); 1261 1262 if (TC_U32_KEY(n->handle)) 1263 if (tcf_exts_dump_stats(skb, &n->exts) < 0) 1264 goto nla_put_failure; 1265 return skb->len; 1266 1267 nla_put_failure: 1268 nla_nest_cancel(skb, nest); 1269 return -1; 1270 } 1271 1272 static struct tcf_proto_ops cls_u32_ops __read_mostly = { 1273 .kind = "u32", 1274 .classify = u32_classify, 1275 .init = u32_init, 1276 .destroy = u32_destroy, 1277 .get = u32_get, 1278 .change = u32_change, 1279 .delete = u32_delete, 1280 .walk = u32_walk, 1281 .dump = u32_dump, 1282 .bind_class = u32_bind_class, 1283 .owner = THIS_MODULE, 1284 }; 1285 1286 static int __init init_u32(void) 1287 { 1288 int i, ret; 1289 1290 pr_info("u32 classifier\n"); 1291 #ifdef CONFIG_CLS_U32_PERF 1292 pr_info(" Performance counters on\n"); 1293 #endif 1294 #ifdef CONFIG_NET_CLS_IND 1295 pr_info(" input device check on\n"); 1296 #endif 1297 #ifdef CONFIG_NET_CLS_ACT 1298 pr_info(" Actions configured\n"); 1299 #endif 1300 tc_u_common_hash = kvmalloc_array(U32_HASH_SIZE, 1301 sizeof(struct hlist_head), 1302 GFP_KERNEL); 1303 if (!tc_u_common_hash) 1304 return -ENOMEM; 1305 1306 for (i = 0; i < U32_HASH_SIZE; i++) 1307 INIT_HLIST_HEAD(&tc_u_common_hash[i]); 1308 1309 ret = register_tcf_proto_ops(&cls_u32_ops); 1310 if (ret) 1311 kvfree(tc_u_common_hash); 1312 return ret; 1313 } 1314 1315 static void __exit exit_u32(void) 1316 { 1317 unregister_tcf_proto_ops(&cls_u32_ops); 1318 kvfree(tc_u_common_hash); 1319 } 1320 1321 module_init(init_u32) 1322 module_exit(exit_u32) 1323 MODULE_LICENSE("GPL"); 1324