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/idr.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 idr handle_idr; 89 struct rcu_head rcu; 90 /* The 'ht' field MUST be the last field in structure to allow for 91 * more entries allocated at end of structure. 92 */ 93 struct tc_u_knode __rcu *ht[1]; 94 }; 95 96 struct tc_u_common { 97 struct tc_u_hnode __rcu *hlist; 98 struct tcf_block *block; 99 int refcnt; 100 struct idr handle_idr; 101 struct hlist_node hnode; 102 struct rcu_head rcu; 103 }; 104 105 static inline unsigned int u32_hash_fold(__be32 key, 106 const struct tc_u32_sel *sel, 107 u8 fshift) 108 { 109 unsigned int h = ntohl(key & sel->hmask) >> fshift; 110 111 return h; 112 } 113 114 static int u32_classify(struct sk_buff *skb, const struct tcf_proto *tp, 115 struct tcf_result *res) 116 { 117 struct { 118 struct tc_u_knode *knode; 119 unsigned int off; 120 } stack[TC_U32_MAXDEPTH]; 121 122 struct tc_u_hnode *ht = rcu_dereference_bh(tp->root); 123 unsigned int off = skb_network_offset(skb); 124 struct tc_u_knode *n; 125 int sdepth = 0; 126 int off2 = 0; 127 int sel = 0; 128 #ifdef CONFIG_CLS_U32_PERF 129 int j; 130 #endif 131 int i, r; 132 133 next_ht: 134 n = rcu_dereference_bh(ht->ht[sel]); 135 136 next_knode: 137 if (n) { 138 struct tc_u32_key *key = n->sel.keys; 139 140 #ifdef CONFIG_CLS_U32_PERF 141 __this_cpu_inc(n->pf->rcnt); 142 j = 0; 143 #endif 144 145 if (tc_skip_sw(n->flags)) { 146 n = rcu_dereference_bh(n->next); 147 goto next_knode; 148 } 149 150 #ifdef CONFIG_CLS_U32_MARK 151 if ((skb->mark & n->mask) != n->val) { 152 n = rcu_dereference_bh(n->next); 153 goto next_knode; 154 } else { 155 __this_cpu_inc(*n->pcpu_success); 156 } 157 #endif 158 159 for (i = n->sel.nkeys; i > 0; i--, key++) { 160 int toff = off + key->off + (off2 & key->offmask); 161 __be32 *data, hdata; 162 163 if (skb_headroom(skb) + toff > INT_MAX) 164 goto out; 165 166 data = skb_header_pointer(skb, toff, 4, &hdata); 167 if (!data) 168 goto out; 169 if ((*data ^ key->val) & key->mask) { 170 n = rcu_dereference_bh(n->next); 171 goto next_knode; 172 } 173 #ifdef CONFIG_CLS_U32_PERF 174 __this_cpu_inc(n->pf->kcnts[j]); 175 j++; 176 #endif 177 } 178 179 ht = rcu_dereference_bh(n->ht_down); 180 if (!ht) { 181 check_terminal: 182 if (n->sel.flags & TC_U32_TERMINAL) { 183 184 *res = n->res; 185 #ifdef CONFIG_NET_CLS_IND 186 if (!tcf_match_indev(skb, n->ifindex)) { 187 n = rcu_dereference_bh(n->next); 188 goto next_knode; 189 } 190 #endif 191 #ifdef CONFIG_CLS_U32_PERF 192 __this_cpu_inc(n->pf->rhit); 193 #endif 194 r = tcf_exts_exec(skb, &n->exts, res); 195 if (r < 0) { 196 n = rcu_dereference_bh(n->next); 197 goto next_knode; 198 } 199 200 return r; 201 } 202 n = rcu_dereference_bh(n->next); 203 goto next_knode; 204 } 205 206 /* PUSH */ 207 if (sdepth >= TC_U32_MAXDEPTH) 208 goto deadloop; 209 stack[sdepth].knode = n; 210 stack[sdepth].off = off; 211 sdepth++; 212 213 ht = rcu_dereference_bh(n->ht_down); 214 sel = 0; 215 if (ht->divisor) { 216 __be32 *data, hdata; 217 218 data = skb_header_pointer(skb, off + n->sel.hoff, 4, 219 &hdata); 220 if (!data) 221 goto out; 222 sel = ht->divisor & u32_hash_fold(*data, &n->sel, 223 n->fshift); 224 } 225 if (!(n->sel.flags & (TC_U32_VAROFFSET | TC_U32_OFFSET | TC_U32_EAT))) 226 goto next_ht; 227 228 if (n->sel.flags & (TC_U32_OFFSET | TC_U32_VAROFFSET)) { 229 off2 = n->sel.off + 3; 230 if (n->sel.flags & TC_U32_VAROFFSET) { 231 __be16 *data, hdata; 232 233 data = skb_header_pointer(skb, 234 off + n->sel.offoff, 235 2, &hdata); 236 if (!data) 237 goto out; 238 off2 += ntohs(n->sel.offmask & *data) >> 239 n->sel.offshift; 240 } 241 off2 &= ~3; 242 } 243 if (n->sel.flags & TC_U32_EAT) { 244 off += off2; 245 off2 = 0; 246 } 247 248 if (off < skb->len) 249 goto next_ht; 250 } 251 252 /* POP */ 253 if (sdepth--) { 254 n = stack[sdepth].knode; 255 ht = rcu_dereference_bh(n->ht_up); 256 off = stack[sdepth].off; 257 goto check_terminal; 258 } 259 out: 260 return -1; 261 262 deadloop: 263 net_warn_ratelimited("cls_u32: dead loop\n"); 264 return -1; 265 } 266 267 static struct tc_u_hnode *u32_lookup_ht(struct tc_u_common *tp_c, u32 handle) 268 { 269 struct tc_u_hnode *ht; 270 271 for (ht = rtnl_dereference(tp_c->hlist); 272 ht; 273 ht = rtnl_dereference(ht->next)) 274 if (ht->handle == handle) 275 break; 276 277 return ht; 278 } 279 280 static struct tc_u_knode *u32_lookup_key(struct tc_u_hnode *ht, u32 handle) 281 { 282 unsigned int sel; 283 struct tc_u_knode *n = NULL; 284 285 sel = TC_U32_HASH(handle); 286 if (sel > ht->divisor) 287 goto out; 288 289 for (n = rtnl_dereference(ht->ht[sel]); 290 n; 291 n = rtnl_dereference(n->next)) 292 if (n->handle == handle) 293 break; 294 out: 295 return n; 296 } 297 298 299 static void *u32_get(struct tcf_proto *tp, u32 handle) 300 { 301 struct tc_u_hnode *ht; 302 struct tc_u_common *tp_c = tp->data; 303 304 if (TC_U32_HTID(handle) == TC_U32_ROOT) 305 ht = rtnl_dereference(tp->root); 306 else 307 ht = u32_lookup_ht(tp_c, TC_U32_HTID(handle)); 308 309 if (!ht) 310 return NULL; 311 312 if (TC_U32_KEY(handle) == 0) 313 return ht; 314 315 return u32_lookup_key(ht, handle); 316 } 317 318 static u32 gen_new_htid(struct tc_u_common *tp_c, struct tc_u_hnode *ptr) 319 { 320 unsigned long idr_index; 321 int err; 322 323 /* This is only used inside rtnl lock it is safe to increment 324 * without read _copy_ update semantics 325 */ 326 err = idr_alloc_ext(&tp_c->handle_idr, ptr, &idr_index, 327 1, 0x7FF, GFP_KERNEL); 328 if (err) 329 return 0; 330 return (u32)(idr_index | 0x800) << 20; 331 } 332 333 static struct hlist_head *tc_u_common_hash; 334 335 #define U32_HASH_SHIFT 10 336 #define U32_HASH_SIZE (1 << U32_HASH_SHIFT) 337 338 static unsigned int tc_u_hash(const struct tcf_proto *tp) 339 { 340 return hash_ptr(tp->chain->block, U32_HASH_SHIFT); 341 } 342 343 static struct tc_u_common *tc_u_common_find(const struct tcf_proto *tp) 344 { 345 struct tc_u_common *tc; 346 unsigned int h; 347 348 h = tc_u_hash(tp); 349 hlist_for_each_entry(tc, &tc_u_common_hash[h], hnode) { 350 if (tc->block == tp->chain->block) 351 return tc; 352 } 353 return NULL; 354 } 355 356 static int u32_init(struct tcf_proto *tp) 357 { 358 struct tc_u_hnode *root_ht; 359 struct tc_u_common *tp_c; 360 unsigned int h; 361 362 tp_c = tc_u_common_find(tp); 363 364 root_ht = kzalloc(sizeof(*root_ht), GFP_KERNEL); 365 if (root_ht == NULL) 366 return -ENOBUFS; 367 368 root_ht->refcnt++; 369 root_ht->handle = tp_c ? gen_new_htid(tp_c, root_ht) : 0x80000000; 370 root_ht->prio = tp->prio; 371 idr_init(&root_ht->handle_idr); 372 373 if (tp_c == NULL) { 374 tp_c = kzalloc(sizeof(*tp_c), GFP_KERNEL); 375 if (tp_c == NULL) { 376 kfree(root_ht); 377 return -ENOBUFS; 378 } 379 tp_c->block = tp->chain->block; 380 INIT_HLIST_NODE(&tp_c->hnode); 381 idr_init(&tp_c->handle_idr); 382 383 h = tc_u_hash(tp); 384 hlist_add_head(&tp_c->hnode, &tc_u_common_hash[h]); 385 } 386 387 tp_c->refcnt++; 388 RCU_INIT_POINTER(root_ht->next, tp_c->hlist); 389 rcu_assign_pointer(tp_c->hlist, root_ht); 390 root_ht->tp_c = tp_c; 391 392 rcu_assign_pointer(tp->root, root_ht); 393 tp->data = tp_c; 394 return 0; 395 } 396 397 static int u32_destroy_key(struct tcf_proto *tp, struct tc_u_knode *n, 398 bool free_pf) 399 { 400 tcf_exts_destroy(&n->exts); 401 tcf_exts_put_net(&n->exts); 402 if (n->ht_down) 403 n->ht_down->refcnt--; 404 #ifdef CONFIG_CLS_U32_PERF 405 if (free_pf) 406 free_percpu(n->pf); 407 #endif 408 #ifdef CONFIG_CLS_U32_MARK 409 if (free_pf) 410 free_percpu(n->pcpu_success); 411 #endif 412 kfree(n); 413 return 0; 414 } 415 416 /* u32_delete_key_rcu should be called when free'ing a copied 417 * version of a tc_u_knode obtained from u32_init_knode(). When 418 * copies are obtained from u32_init_knode() the statistics are 419 * shared between the old and new copies to allow readers to 420 * continue to update the statistics during the copy. To support 421 * this the u32_delete_key_rcu variant does not free the percpu 422 * statistics. 423 */ 424 static void u32_delete_key_work(struct work_struct *work) 425 { 426 struct tc_u_knode *key = container_of(work, struct tc_u_knode, work); 427 428 rtnl_lock(); 429 u32_destroy_key(key->tp, key, false); 430 rtnl_unlock(); 431 } 432 433 static void u32_delete_key_rcu(struct rcu_head *rcu) 434 { 435 struct tc_u_knode *key = container_of(rcu, struct tc_u_knode, rcu); 436 437 INIT_WORK(&key->work, u32_delete_key_work); 438 tcf_queue_work(&key->work); 439 } 440 441 /* u32_delete_key_freepf_rcu is the rcu callback variant 442 * that free's the entire structure including the statistics 443 * percpu variables. Only use this if the key is not a copy 444 * returned by u32_init_knode(). See u32_delete_key_rcu() 445 * for the variant that should be used with keys return from 446 * u32_init_knode() 447 */ 448 static void u32_delete_key_freepf_work(struct work_struct *work) 449 { 450 struct tc_u_knode *key = container_of(work, struct tc_u_knode, work); 451 452 rtnl_lock(); 453 u32_destroy_key(key->tp, key, true); 454 rtnl_unlock(); 455 } 456 457 static void u32_delete_key_freepf_rcu(struct rcu_head *rcu) 458 { 459 struct tc_u_knode *key = container_of(rcu, struct tc_u_knode, rcu); 460 461 INIT_WORK(&key->work, u32_delete_key_freepf_work); 462 tcf_queue_work(&key->work); 463 } 464 465 static int u32_delete_key(struct tcf_proto *tp, struct tc_u_knode *key) 466 { 467 struct tc_u_knode __rcu **kp; 468 struct tc_u_knode *pkp; 469 struct tc_u_hnode *ht = rtnl_dereference(key->ht_up); 470 471 if (ht) { 472 kp = &ht->ht[TC_U32_HASH(key->handle)]; 473 for (pkp = rtnl_dereference(*kp); pkp; 474 kp = &pkp->next, pkp = rtnl_dereference(*kp)) { 475 if (pkp == key) { 476 RCU_INIT_POINTER(*kp, key->next); 477 478 tcf_unbind_filter(tp, &key->res); 479 tcf_exts_get_net(&key->exts); 480 call_rcu(&key->rcu, u32_delete_key_freepf_rcu); 481 return 0; 482 } 483 } 484 } 485 WARN_ON(1); 486 return 0; 487 } 488 489 static void u32_clear_hw_hnode(struct tcf_proto *tp, struct tc_u_hnode *h) 490 { 491 struct tcf_block *block = tp->chain->block; 492 struct tc_cls_u32_offload cls_u32 = {}; 493 494 tc_cls_common_offload_init(&cls_u32.common, tp); 495 cls_u32.command = TC_CLSU32_DELETE_HNODE; 496 cls_u32.hnode.divisor = h->divisor; 497 cls_u32.hnode.handle = h->handle; 498 cls_u32.hnode.prio = h->prio; 499 500 tc_setup_cb_call(block, NULL, TC_SETUP_CLSU32, &cls_u32, false); 501 } 502 503 static int u32_replace_hw_hnode(struct tcf_proto *tp, struct tc_u_hnode *h, 504 u32 flags) 505 { 506 struct tcf_block *block = tp->chain->block; 507 struct tc_cls_u32_offload cls_u32 = {}; 508 bool skip_sw = tc_skip_sw(flags); 509 bool offloaded = false; 510 int err; 511 512 tc_cls_common_offload_init(&cls_u32.common, tp); 513 cls_u32.command = TC_CLSU32_NEW_HNODE; 514 cls_u32.hnode.divisor = h->divisor; 515 cls_u32.hnode.handle = h->handle; 516 cls_u32.hnode.prio = h->prio; 517 518 err = tc_setup_cb_call(block, NULL, TC_SETUP_CLSU32, &cls_u32, skip_sw); 519 if (err < 0) { 520 u32_clear_hw_hnode(tp, h); 521 return err; 522 } else if (err > 0) { 523 offloaded = true; 524 } 525 526 if (skip_sw && !offloaded) 527 return -EINVAL; 528 529 return 0; 530 } 531 532 static void u32_remove_hw_knode(struct tcf_proto *tp, struct tc_u_knode *n) 533 { 534 struct tcf_block *block = tp->chain->block; 535 struct tc_cls_u32_offload cls_u32 = {}; 536 537 tc_cls_common_offload_init(&cls_u32.common, tp); 538 cls_u32.command = TC_CLSU32_DELETE_KNODE; 539 cls_u32.knode.handle = n->handle; 540 541 tc_setup_cb_call(block, NULL, TC_SETUP_CLSU32, &cls_u32, false); 542 tcf_block_offload_dec(block, &n->flags); 543 } 544 545 static int u32_replace_hw_knode(struct tcf_proto *tp, struct tc_u_knode *n, 546 u32 flags) 547 { 548 struct tcf_block *block = tp->chain->block; 549 struct tc_cls_u32_offload cls_u32 = {}; 550 bool skip_sw = tc_skip_sw(flags); 551 int err; 552 553 tc_cls_common_offload_init(&cls_u32.common, tp); 554 cls_u32.command = TC_CLSU32_REPLACE_KNODE; 555 cls_u32.knode.handle = n->handle; 556 cls_u32.knode.fshift = n->fshift; 557 #ifdef CONFIG_CLS_U32_MARK 558 cls_u32.knode.val = n->val; 559 cls_u32.knode.mask = n->mask; 560 #else 561 cls_u32.knode.val = 0; 562 cls_u32.knode.mask = 0; 563 #endif 564 cls_u32.knode.sel = &n->sel; 565 cls_u32.knode.exts = &n->exts; 566 if (n->ht_down) 567 cls_u32.knode.link_handle = n->ht_down->handle; 568 569 err = tc_setup_cb_call(block, NULL, TC_SETUP_CLSU32, &cls_u32, skip_sw); 570 if (err < 0) { 571 u32_remove_hw_knode(tp, n); 572 return err; 573 } else if (err > 0) { 574 tcf_block_offload_inc(block, &n->flags); 575 } 576 577 if (skip_sw && !(n->flags & TCA_CLS_FLAGS_IN_HW)) 578 return -EINVAL; 579 580 return 0; 581 } 582 583 static void u32_clear_hnode(struct tcf_proto *tp, struct tc_u_hnode *ht) 584 { 585 struct tc_u_knode *n; 586 unsigned int h; 587 588 for (h = 0; h <= ht->divisor; h++) { 589 while ((n = rtnl_dereference(ht->ht[h])) != NULL) { 590 RCU_INIT_POINTER(ht->ht[h], 591 rtnl_dereference(n->next)); 592 tcf_unbind_filter(tp, &n->res); 593 u32_remove_hw_knode(tp, n); 594 idr_remove_ext(&ht->handle_idr, n->handle); 595 if (tcf_exts_get_net(&n->exts)) 596 call_rcu(&n->rcu, u32_delete_key_freepf_rcu); 597 else 598 u32_destroy_key(n->tp, n, true); 599 } 600 } 601 } 602 603 static int u32_destroy_hnode(struct tcf_proto *tp, struct tc_u_hnode *ht) 604 { 605 struct tc_u_common *tp_c = tp->data; 606 struct tc_u_hnode __rcu **hn; 607 struct tc_u_hnode *phn; 608 609 WARN_ON(ht->refcnt); 610 611 u32_clear_hnode(tp, ht); 612 613 hn = &tp_c->hlist; 614 for (phn = rtnl_dereference(*hn); 615 phn; 616 hn = &phn->next, phn = rtnl_dereference(*hn)) { 617 if (phn == ht) { 618 u32_clear_hw_hnode(tp, ht); 619 idr_destroy(&ht->handle_idr); 620 idr_remove_ext(&tp_c->handle_idr, ht->handle); 621 RCU_INIT_POINTER(*hn, ht->next); 622 kfree_rcu(ht, rcu); 623 return 0; 624 } 625 } 626 627 return -ENOENT; 628 } 629 630 static bool ht_empty(struct tc_u_hnode *ht) 631 { 632 unsigned int h; 633 634 for (h = 0; h <= ht->divisor; h++) 635 if (rcu_access_pointer(ht->ht[h])) 636 return false; 637 638 return true; 639 } 640 641 static void u32_destroy(struct tcf_proto *tp) 642 { 643 struct tc_u_common *tp_c = tp->data; 644 struct tc_u_hnode *root_ht = rtnl_dereference(tp->root); 645 646 WARN_ON(root_ht == NULL); 647 648 if (root_ht && --root_ht->refcnt == 0) 649 u32_destroy_hnode(tp, root_ht); 650 651 if (--tp_c->refcnt == 0) { 652 struct tc_u_hnode *ht; 653 654 hlist_del(&tp_c->hnode); 655 656 for (ht = rtnl_dereference(tp_c->hlist); 657 ht; 658 ht = rtnl_dereference(ht->next)) { 659 ht->refcnt--; 660 u32_clear_hnode(tp, ht); 661 } 662 663 while ((ht = rtnl_dereference(tp_c->hlist)) != NULL) { 664 RCU_INIT_POINTER(tp_c->hlist, ht->next); 665 kfree_rcu(ht, rcu); 666 } 667 668 idr_destroy(&tp_c->handle_idr); 669 kfree(tp_c); 670 } 671 672 tp->data = NULL; 673 } 674 675 static int u32_delete(struct tcf_proto *tp, void *arg, bool *last) 676 { 677 struct tc_u_hnode *ht = arg; 678 struct tc_u_hnode *root_ht = rtnl_dereference(tp->root); 679 struct tc_u_common *tp_c = tp->data; 680 int ret = 0; 681 682 if (ht == NULL) 683 goto out; 684 685 if (TC_U32_KEY(ht->handle)) { 686 u32_remove_hw_knode(tp, (struct tc_u_knode *)ht); 687 ret = u32_delete_key(tp, (struct tc_u_knode *)ht); 688 goto out; 689 } 690 691 if (root_ht == ht) 692 return -EINVAL; 693 694 if (ht->refcnt == 1) { 695 ht->refcnt--; 696 u32_destroy_hnode(tp, ht); 697 } else { 698 return -EBUSY; 699 } 700 701 out: 702 *last = true; 703 if (root_ht) { 704 if (root_ht->refcnt > 1) { 705 *last = false; 706 goto ret; 707 } 708 if (root_ht->refcnt == 1) { 709 if (!ht_empty(root_ht)) { 710 *last = false; 711 goto ret; 712 } 713 } 714 } 715 716 if (tp_c->refcnt > 1) { 717 *last = false; 718 goto ret; 719 } 720 721 if (tp_c->refcnt == 1) { 722 struct tc_u_hnode *ht; 723 724 for (ht = rtnl_dereference(tp_c->hlist); 725 ht; 726 ht = rtnl_dereference(ht->next)) 727 if (!ht_empty(ht)) { 728 *last = false; 729 break; 730 } 731 } 732 733 ret: 734 return ret; 735 } 736 737 static u32 gen_new_kid(struct tc_u_hnode *ht, u32 htid) 738 { 739 unsigned long idr_index; 740 u32 start = htid | 0x800; 741 u32 max = htid | 0xFFF; 742 u32 min = htid; 743 744 if (idr_alloc_ext(&ht->handle_idr, NULL, &idr_index, 745 start, max + 1, GFP_KERNEL)) { 746 if (idr_alloc_ext(&ht->handle_idr, NULL, &idr_index, 747 min + 1, max + 1, GFP_KERNEL)) 748 return max; 749 } 750 751 return (u32)idr_index; 752 } 753 754 static const struct nla_policy u32_policy[TCA_U32_MAX + 1] = { 755 [TCA_U32_CLASSID] = { .type = NLA_U32 }, 756 [TCA_U32_HASH] = { .type = NLA_U32 }, 757 [TCA_U32_LINK] = { .type = NLA_U32 }, 758 [TCA_U32_DIVISOR] = { .type = NLA_U32 }, 759 [TCA_U32_SEL] = { .len = sizeof(struct tc_u32_sel) }, 760 [TCA_U32_INDEV] = { .type = NLA_STRING, .len = IFNAMSIZ }, 761 [TCA_U32_MARK] = { .len = sizeof(struct tc_u32_mark) }, 762 [TCA_U32_FLAGS] = { .type = NLA_U32 }, 763 }; 764 765 static int u32_set_parms(struct net *net, struct tcf_proto *tp, 766 unsigned long base, struct tc_u_hnode *ht, 767 struct tc_u_knode *n, struct nlattr **tb, 768 struct nlattr *est, bool ovr) 769 { 770 int err; 771 772 err = tcf_exts_validate(net, tp, tb, est, &n->exts, ovr); 773 if (err < 0) 774 return err; 775 776 if (tb[TCA_U32_LINK]) { 777 u32 handle = nla_get_u32(tb[TCA_U32_LINK]); 778 struct tc_u_hnode *ht_down = NULL, *ht_old; 779 780 if (TC_U32_KEY(handle)) 781 return -EINVAL; 782 783 if (handle) { 784 ht_down = u32_lookup_ht(ht->tp_c, handle); 785 786 if (!ht_down) 787 return -EINVAL; 788 ht_down->refcnt++; 789 } 790 791 ht_old = rtnl_dereference(n->ht_down); 792 rcu_assign_pointer(n->ht_down, ht_down); 793 794 if (ht_old) 795 ht_old->refcnt--; 796 } 797 if (tb[TCA_U32_CLASSID]) { 798 n->res.classid = nla_get_u32(tb[TCA_U32_CLASSID]); 799 tcf_bind_filter(tp, &n->res, base); 800 } 801 802 #ifdef CONFIG_NET_CLS_IND 803 if (tb[TCA_U32_INDEV]) { 804 int ret; 805 ret = tcf_change_indev(net, tb[TCA_U32_INDEV]); 806 if (ret < 0) 807 return -EINVAL; 808 n->ifindex = ret; 809 } 810 #endif 811 return 0; 812 } 813 814 static void u32_replace_knode(struct tcf_proto *tp, struct tc_u_common *tp_c, 815 struct tc_u_knode *n) 816 { 817 struct tc_u_knode __rcu **ins; 818 struct tc_u_knode *pins; 819 struct tc_u_hnode *ht; 820 821 if (TC_U32_HTID(n->handle) == TC_U32_ROOT) 822 ht = rtnl_dereference(tp->root); 823 else 824 ht = u32_lookup_ht(tp_c, TC_U32_HTID(n->handle)); 825 826 ins = &ht->ht[TC_U32_HASH(n->handle)]; 827 828 /* The node must always exist for it to be replaced if this is not the 829 * case then something went very wrong elsewhere. 830 */ 831 for (pins = rtnl_dereference(*ins); ; 832 ins = &pins->next, pins = rtnl_dereference(*ins)) 833 if (pins->handle == n->handle) 834 break; 835 836 idr_replace_ext(&ht->handle_idr, n, n->handle); 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) 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 ht = kzalloc(sizeof(*ht) + divisor*sizeof(void *), GFP_KERNEL); 970 if (ht == NULL) 971 return -ENOBUFS; 972 if (handle == 0) { 973 handle = gen_new_htid(tp->data, ht); 974 if (handle == 0) { 975 kfree(ht); 976 return -ENOMEM; 977 } 978 } else { 979 err = idr_alloc_ext(&tp_c->handle_idr, ht, NULL, 980 handle, handle + 1, GFP_KERNEL); 981 if (err) { 982 kfree(ht); 983 return err; 984 } 985 } 986 ht->tp_c = tp_c; 987 ht->refcnt = 1; 988 ht->divisor = divisor; 989 ht->handle = handle; 990 ht->prio = tp->prio; 991 idr_init(&ht->handle_idr); 992 993 err = u32_replace_hw_hnode(tp, ht, flags); 994 if (err) { 995 idr_remove_ext(&tp_c->handle_idr, handle); 996 kfree(ht); 997 return err; 998 } 999 1000 RCU_INIT_POINTER(ht->next, tp_c->hlist); 1001 rcu_assign_pointer(tp_c->hlist, ht); 1002 *arg = ht; 1003 1004 return 0; 1005 } 1006 1007 if (tb[TCA_U32_HASH]) { 1008 htid = nla_get_u32(tb[TCA_U32_HASH]); 1009 if (TC_U32_HTID(htid) == TC_U32_ROOT) { 1010 ht = rtnl_dereference(tp->root); 1011 htid = ht->handle; 1012 } else { 1013 ht = u32_lookup_ht(tp->data, TC_U32_HTID(htid)); 1014 if (!ht) 1015 return -EINVAL; 1016 } 1017 } else { 1018 ht = rtnl_dereference(tp->root); 1019 htid = ht->handle; 1020 } 1021 1022 if (ht->divisor < TC_U32_HASH(htid)) 1023 return -EINVAL; 1024 1025 if (handle) { 1026 if (TC_U32_HTID(handle) && TC_U32_HTID(handle ^ htid)) 1027 return -EINVAL; 1028 handle = htid | TC_U32_NODE(handle); 1029 err = idr_alloc_ext(&ht->handle_idr, NULL, NULL, 1030 handle, handle + 1, 1031 GFP_KERNEL); 1032 if (err) 1033 return err; 1034 } else 1035 handle = gen_new_kid(ht, htid); 1036 1037 if (tb[TCA_U32_SEL] == NULL) { 1038 err = -EINVAL; 1039 goto erridr; 1040 } 1041 1042 s = nla_data(tb[TCA_U32_SEL]); 1043 1044 n = kzalloc(sizeof(*n) + s->nkeys*sizeof(struct tc_u32_key), GFP_KERNEL); 1045 if (n == NULL) { 1046 err = -ENOBUFS; 1047 goto erridr; 1048 } 1049 1050 #ifdef CONFIG_CLS_U32_PERF 1051 size = sizeof(struct tc_u32_pcnt) + s->nkeys * sizeof(u64); 1052 n->pf = __alloc_percpu(size, __alignof__(struct tc_u32_pcnt)); 1053 if (!n->pf) { 1054 err = -ENOBUFS; 1055 goto errfree; 1056 } 1057 #endif 1058 1059 memcpy(&n->sel, s, sizeof(*s) + s->nkeys*sizeof(struct tc_u32_key)); 1060 RCU_INIT_POINTER(n->ht_up, ht); 1061 n->handle = handle; 1062 n->fshift = s->hmask ? ffs(ntohl(s->hmask)) - 1 : 0; 1063 n->flags = flags; 1064 n->tp = tp; 1065 1066 err = tcf_exts_init(&n->exts, TCA_U32_ACT, TCA_U32_POLICE); 1067 if (err < 0) 1068 goto errout; 1069 1070 #ifdef CONFIG_CLS_U32_MARK 1071 n->pcpu_success = alloc_percpu(u32); 1072 if (!n->pcpu_success) { 1073 err = -ENOMEM; 1074 goto errout; 1075 } 1076 1077 if (tb[TCA_U32_MARK]) { 1078 struct tc_u32_mark *mark; 1079 1080 mark = nla_data(tb[TCA_U32_MARK]); 1081 n->val = mark->val; 1082 n->mask = mark->mask; 1083 } 1084 #endif 1085 1086 err = u32_set_parms(net, tp, base, ht, n, tb, tca[TCA_RATE], ovr); 1087 if (err == 0) { 1088 struct tc_u_knode __rcu **ins; 1089 struct tc_u_knode *pins; 1090 1091 err = u32_replace_hw_knode(tp, n, flags); 1092 if (err) 1093 goto errhw; 1094 1095 if (!tc_in_hw(n->flags)) 1096 n->flags |= TCA_CLS_FLAGS_NOT_IN_HW; 1097 1098 ins = &ht->ht[TC_U32_HASH(handle)]; 1099 for (pins = rtnl_dereference(*ins); pins; 1100 ins = &pins->next, pins = rtnl_dereference(*ins)) 1101 if (TC_U32_NODE(handle) < TC_U32_NODE(pins->handle)) 1102 break; 1103 1104 RCU_INIT_POINTER(n->next, pins); 1105 rcu_assign_pointer(*ins, n); 1106 *arg = n; 1107 return 0; 1108 } 1109 1110 errhw: 1111 #ifdef CONFIG_CLS_U32_MARK 1112 free_percpu(n->pcpu_success); 1113 #endif 1114 1115 errout: 1116 tcf_exts_destroy(&n->exts); 1117 #ifdef CONFIG_CLS_U32_PERF 1118 errfree: 1119 free_percpu(n->pf); 1120 #endif 1121 kfree(n); 1122 erridr: 1123 idr_remove_ext(&ht->handle_idr, handle); 1124 return err; 1125 } 1126 1127 static void u32_walk(struct tcf_proto *tp, struct tcf_walker *arg) 1128 { 1129 struct tc_u_common *tp_c = tp->data; 1130 struct tc_u_hnode *ht; 1131 struct tc_u_knode *n; 1132 unsigned int h; 1133 1134 if (arg->stop) 1135 return; 1136 1137 for (ht = rtnl_dereference(tp_c->hlist); 1138 ht; 1139 ht = rtnl_dereference(ht->next)) { 1140 if (ht->prio != tp->prio) 1141 continue; 1142 if (arg->count >= arg->skip) { 1143 if (arg->fn(tp, ht, arg) < 0) { 1144 arg->stop = 1; 1145 return; 1146 } 1147 } 1148 arg->count++; 1149 for (h = 0; h <= ht->divisor; h++) { 1150 for (n = rtnl_dereference(ht->ht[h]); 1151 n; 1152 n = rtnl_dereference(n->next)) { 1153 if (arg->count < arg->skip) { 1154 arg->count++; 1155 continue; 1156 } 1157 if (arg->fn(tp, n, arg) < 0) { 1158 arg->stop = 1; 1159 return; 1160 } 1161 arg->count++; 1162 } 1163 } 1164 } 1165 } 1166 1167 static void u32_bind_class(void *fh, u32 classid, unsigned long cl) 1168 { 1169 struct tc_u_knode *n = fh; 1170 1171 if (n && n->res.classid == classid) 1172 n->res.class = cl; 1173 } 1174 1175 static int u32_dump(struct net *net, struct tcf_proto *tp, void *fh, 1176 struct sk_buff *skb, struct tcmsg *t) 1177 { 1178 struct tc_u_knode *n = fh; 1179 struct tc_u_hnode *ht_up, *ht_down; 1180 struct nlattr *nest; 1181 1182 if (n == NULL) 1183 return skb->len; 1184 1185 t->tcm_handle = n->handle; 1186 1187 nest = nla_nest_start(skb, TCA_OPTIONS); 1188 if (nest == NULL) 1189 goto nla_put_failure; 1190 1191 if (TC_U32_KEY(n->handle) == 0) { 1192 struct tc_u_hnode *ht = fh; 1193 u32 divisor = ht->divisor + 1; 1194 1195 if (nla_put_u32(skb, TCA_U32_DIVISOR, divisor)) 1196 goto nla_put_failure; 1197 } else { 1198 #ifdef CONFIG_CLS_U32_PERF 1199 struct tc_u32_pcnt *gpf; 1200 int cpu; 1201 #endif 1202 1203 if (nla_put(skb, TCA_U32_SEL, 1204 sizeof(n->sel) + n->sel.nkeys*sizeof(struct tc_u32_key), 1205 &n->sel)) 1206 goto nla_put_failure; 1207 1208 ht_up = rtnl_dereference(n->ht_up); 1209 if (ht_up) { 1210 u32 htid = n->handle & 0xFFFFF000; 1211 if (nla_put_u32(skb, TCA_U32_HASH, htid)) 1212 goto nla_put_failure; 1213 } 1214 if (n->res.classid && 1215 nla_put_u32(skb, TCA_U32_CLASSID, n->res.classid)) 1216 goto nla_put_failure; 1217 1218 ht_down = rtnl_dereference(n->ht_down); 1219 if (ht_down && 1220 nla_put_u32(skb, TCA_U32_LINK, ht_down->handle)) 1221 goto nla_put_failure; 1222 1223 if (n->flags && nla_put_u32(skb, TCA_U32_FLAGS, n->flags)) 1224 goto nla_put_failure; 1225 1226 #ifdef CONFIG_CLS_U32_MARK 1227 if ((n->val || n->mask)) { 1228 struct tc_u32_mark mark = {.val = n->val, 1229 .mask = n->mask, 1230 .success = 0}; 1231 int cpum; 1232 1233 for_each_possible_cpu(cpum) { 1234 __u32 cnt = *per_cpu_ptr(n->pcpu_success, cpum); 1235 1236 mark.success += cnt; 1237 } 1238 1239 if (nla_put(skb, TCA_U32_MARK, sizeof(mark), &mark)) 1240 goto nla_put_failure; 1241 } 1242 #endif 1243 1244 if (tcf_exts_dump(skb, &n->exts) < 0) 1245 goto nla_put_failure; 1246 1247 #ifdef CONFIG_NET_CLS_IND 1248 if (n->ifindex) { 1249 struct net_device *dev; 1250 dev = __dev_get_by_index(net, n->ifindex); 1251 if (dev && nla_put_string(skb, TCA_U32_INDEV, dev->name)) 1252 goto nla_put_failure; 1253 } 1254 #endif 1255 #ifdef CONFIG_CLS_U32_PERF 1256 gpf = kzalloc(sizeof(struct tc_u32_pcnt) + 1257 n->sel.nkeys * sizeof(u64), 1258 GFP_KERNEL); 1259 if (!gpf) 1260 goto nla_put_failure; 1261 1262 for_each_possible_cpu(cpu) { 1263 int i; 1264 struct tc_u32_pcnt *pf = per_cpu_ptr(n->pf, cpu); 1265 1266 gpf->rcnt += pf->rcnt; 1267 gpf->rhit += pf->rhit; 1268 for (i = 0; i < n->sel.nkeys; i++) 1269 gpf->kcnts[i] += pf->kcnts[i]; 1270 } 1271 1272 if (nla_put_64bit(skb, TCA_U32_PCNT, 1273 sizeof(struct tc_u32_pcnt) + 1274 n->sel.nkeys * sizeof(u64), 1275 gpf, TCA_U32_PAD)) { 1276 kfree(gpf); 1277 goto nla_put_failure; 1278 } 1279 kfree(gpf); 1280 #endif 1281 } 1282 1283 nla_nest_end(skb, nest); 1284 1285 if (TC_U32_KEY(n->handle)) 1286 if (tcf_exts_dump_stats(skb, &n->exts) < 0) 1287 goto nla_put_failure; 1288 return skb->len; 1289 1290 nla_put_failure: 1291 nla_nest_cancel(skb, nest); 1292 return -1; 1293 } 1294 1295 static struct tcf_proto_ops cls_u32_ops __read_mostly = { 1296 .kind = "u32", 1297 .classify = u32_classify, 1298 .init = u32_init, 1299 .destroy = u32_destroy, 1300 .get = u32_get, 1301 .change = u32_change, 1302 .delete = u32_delete, 1303 .walk = u32_walk, 1304 .dump = u32_dump, 1305 .bind_class = u32_bind_class, 1306 .owner = THIS_MODULE, 1307 }; 1308 1309 static int __init init_u32(void) 1310 { 1311 int i, ret; 1312 1313 pr_info("u32 classifier\n"); 1314 #ifdef CONFIG_CLS_U32_PERF 1315 pr_info(" Performance counters on\n"); 1316 #endif 1317 #ifdef CONFIG_NET_CLS_IND 1318 pr_info(" input device check on\n"); 1319 #endif 1320 #ifdef CONFIG_NET_CLS_ACT 1321 pr_info(" Actions configured\n"); 1322 #endif 1323 tc_u_common_hash = kvmalloc_array(U32_HASH_SIZE, 1324 sizeof(struct hlist_head), 1325 GFP_KERNEL); 1326 if (!tc_u_common_hash) 1327 return -ENOMEM; 1328 1329 for (i = 0; i < U32_HASH_SIZE; i++) 1330 INIT_HLIST_HEAD(&tc_u_common_hash[i]); 1331 1332 ret = register_tcf_proto_ops(&cls_u32_ops); 1333 if (ret) 1334 kvfree(tc_u_common_hash); 1335 return ret; 1336 } 1337 1338 static void __exit exit_u32(void) 1339 { 1340 unregister_tcf_proto_ops(&cls_u32_ops); 1341 kvfree(tc_u_common_hash); 1342 } 1343 1344 module_init(init_u32) 1345 module_exit(exit_u32) 1346 MODULE_LICENSE("GPL"); 1347