1 /* 2 * Copyright (c) 2007-2014 Nicira, Inc. 3 * 4 * This program is free software; you can redistribute it and/or 5 * modify it under the terms of version 2 of the GNU General Public 6 * License as published by the Free Software Foundation. 7 * 8 * This program is distributed in the hope that it will be useful, but 9 * WITHOUT ANY WARRANTY; without even the implied warranty of 10 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU 11 * General Public License for more details. 12 * 13 * You should have received a copy of the GNU General Public License 14 * along with this program; if not, write to the Free Software 15 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 16 * 02110-1301, USA 17 */ 18 19 #include "flow.h" 20 #include "datapath.h" 21 #include "flow_netlink.h" 22 #include <linux/uaccess.h> 23 #include <linux/netdevice.h> 24 #include <linux/etherdevice.h> 25 #include <linux/if_ether.h> 26 #include <linux/if_vlan.h> 27 #include <net/llc_pdu.h> 28 #include <linux/kernel.h> 29 #include <linux/jhash.h> 30 #include <linux/jiffies.h> 31 #include <linux/llc.h> 32 #include <linux/module.h> 33 #include <linux/in.h> 34 #include <linux/rcupdate.h> 35 #include <linux/cpumask.h> 36 #include <linux/if_arp.h> 37 #include <linux/ip.h> 38 #include <linux/ipv6.h> 39 #include <linux/sctp.h> 40 #include <linux/tcp.h> 41 #include <linux/udp.h> 42 #include <linux/icmp.h> 43 #include <linux/icmpv6.h> 44 #include <linux/rculist.h> 45 #include <net/ip.h> 46 #include <net/ipv6.h> 47 #include <net/ndisc.h> 48 49 #define TBL_MIN_BUCKETS 1024 50 #define REHASH_INTERVAL (10 * 60 * HZ) 51 52 static struct kmem_cache *flow_cache; 53 struct kmem_cache *flow_stats_cache __read_mostly; 54 55 static u16 range_n_bytes(const struct sw_flow_key_range *range) 56 { 57 return range->end - range->start; 58 } 59 60 void ovs_flow_mask_key(struct sw_flow_key *dst, const struct sw_flow_key *src, 61 bool full, const struct sw_flow_mask *mask) 62 { 63 int start = full ? 0 : mask->range.start; 64 int len = full ? sizeof *dst : range_n_bytes(&mask->range); 65 const long *m = (const long *)((const u8 *)&mask->key + start); 66 const long *s = (const long *)((const u8 *)src + start); 67 long *d = (long *)((u8 *)dst + start); 68 int i; 69 70 /* If 'full' is true then all of 'dst' is fully initialized. Otherwise, 71 * if 'full' is false the memory outside of the 'mask->range' is left 72 * uninitialized. This can be used as an optimization when further 73 * operations on 'dst' only use contents within 'mask->range'. 74 */ 75 for (i = 0; i < len; i += sizeof(long)) 76 *d++ = *s++ & *m++; 77 } 78 79 struct sw_flow *ovs_flow_alloc(void) 80 { 81 struct sw_flow *flow; 82 struct flow_stats *stats; 83 84 flow = kmem_cache_zalloc(flow_cache, GFP_KERNEL); 85 if (!flow) 86 return ERR_PTR(-ENOMEM); 87 88 flow->stats_last_writer = -1; 89 90 /* Initialize the default stat node. */ 91 stats = kmem_cache_alloc_node(flow_stats_cache, 92 GFP_KERNEL | __GFP_ZERO, 93 node_online(0) ? 0 : NUMA_NO_NODE); 94 if (!stats) 95 goto err; 96 97 spin_lock_init(&stats->lock); 98 99 RCU_INIT_POINTER(flow->stats[0], stats); 100 101 return flow; 102 err: 103 kmem_cache_free(flow_cache, flow); 104 return ERR_PTR(-ENOMEM); 105 } 106 107 int ovs_flow_tbl_count(const struct flow_table *table) 108 { 109 return table->count; 110 } 111 112 static struct flex_array *alloc_buckets(unsigned int n_buckets) 113 { 114 struct flex_array *buckets; 115 int i, err; 116 117 buckets = flex_array_alloc(sizeof(struct hlist_head), 118 n_buckets, GFP_KERNEL); 119 if (!buckets) 120 return NULL; 121 122 err = flex_array_prealloc(buckets, 0, n_buckets, GFP_KERNEL); 123 if (err) { 124 flex_array_free(buckets); 125 return NULL; 126 } 127 128 for (i = 0; i < n_buckets; i++) 129 INIT_HLIST_HEAD((struct hlist_head *) 130 flex_array_get(buckets, i)); 131 132 return buckets; 133 } 134 135 static void flow_free(struct sw_flow *flow) 136 { 137 int cpu; 138 139 if (ovs_identifier_is_key(&flow->id)) 140 kfree(flow->id.unmasked_key); 141 if (flow->sf_acts) 142 ovs_nla_free_flow_actions((struct sw_flow_actions __force *)flow->sf_acts); 143 /* We open code this to make sure cpu 0 is always considered */ 144 for (cpu = 0; cpu < nr_cpu_ids; cpu = cpumask_next(cpu, cpu_possible_mask)) 145 if (flow->stats[cpu]) 146 kmem_cache_free(flow_stats_cache, 147 (struct flow_stats __force *)flow->stats[cpu]); 148 kmem_cache_free(flow_cache, flow); 149 } 150 151 static void rcu_free_flow_callback(struct rcu_head *rcu) 152 { 153 struct sw_flow *flow = container_of(rcu, struct sw_flow, rcu); 154 155 flow_free(flow); 156 } 157 158 void ovs_flow_free(struct sw_flow *flow, bool deferred) 159 { 160 if (!flow) 161 return; 162 163 if (deferred) 164 call_rcu(&flow->rcu, rcu_free_flow_callback); 165 else 166 flow_free(flow); 167 } 168 169 static void free_buckets(struct flex_array *buckets) 170 { 171 flex_array_free(buckets); 172 } 173 174 175 static void __table_instance_destroy(struct table_instance *ti) 176 { 177 free_buckets(ti->buckets); 178 kfree(ti); 179 } 180 181 static struct table_instance *table_instance_alloc(int new_size) 182 { 183 struct table_instance *ti = kmalloc(sizeof(*ti), GFP_KERNEL); 184 185 if (!ti) 186 return NULL; 187 188 ti->buckets = alloc_buckets(new_size); 189 190 if (!ti->buckets) { 191 kfree(ti); 192 return NULL; 193 } 194 ti->n_buckets = new_size; 195 ti->node_ver = 0; 196 ti->keep_flows = false; 197 get_random_bytes(&ti->hash_seed, sizeof(u32)); 198 199 return ti; 200 } 201 202 int ovs_flow_tbl_init(struct flow_table *table) 203 { 204 struct table_instance *ti, *ufid_ti; 205 206 ti = table_instance_alloc(TBL_MIN_BUCKETS); 207 208 if (!ti) 209 return -ENOMEM; 210 211 ufid_ti = table_instance_alloc(TBL_MIN_BUCKETS); 212 if (!ufid_ti) 213 goto free_ti; 214 215 rcu_assign_pointer(table->ti, ti); 216 rcu_assign_pointer(table->ufid_ti, ufid_ti); 217 INIT_LIST_HEAD(&table->mask_list); 218 table->last_rehash = jiffies; 219 table->count = 0; 220 table->ufid_count = 0; 221 return 0; 222 223 free_ti: 224 __table_instance_destroy(ti); 225 return -ENOMEM; 226 } 227 228 static void flow_tbl_destroy_rcu_cb(struct rcu_head *rcu) 229 { 230 struct table_instance *ti = container_of(rcu, struct table_instance, rcu); 231 232 __table_instance_destroy(ti); 233 } 234 235 static void table_instance_destroy(struct table_instance *ti, 236 struct table_instance *ufid_ti, 237 bool deferred) 238 { 239 int i; 240 241 if (!ti) 242 return; 243 244 BUG_ON(!ufid_ti); 245 if (ti->keep_flows) 246 goto skip_flows; 247 248 for (i = 0; i < ti->n_buckets; i++) { 249 struct sw_flow *flow; 250 struct hlist_head *head = flex_array_get(ti->buckets, i); 251 struct hlist_node *n; 252 int ver = ti->node_ver; 253 int ufid_ver = ufid_ti->node_ver; 254 255 hlist_for_each_entry_safe(flow, n, head, flow_table.node[ver]) { 256 hlist_del_rcu(&flow->flow_table.node[ver]); 257 if (ovs_identifier_is_ufid(&flow->id)) 258 hlist_del_rcu(&flow->ufid_table.node[ufid_ver]); 259 ovs_flow_free(flow, deferred); 260 } 261 } 262 263 skip_flows: 264 if (deferred) { 265 call_rcu(&ti->rcu, flow_tbl_destroy_rcu_cb); 266 call_rcu(&ufid_ti->rcu, flow_tbl_destroy_rcu_cb); 267 } else { 268 __table_instance_destroy(ti); 269 __table_instance_destroy(ufid_ti); 270 } 271 } 272 273 /* No need for locking this function is called from RCU callback or 274 * error path. 275 */ 276 void ovs_flow_tbl_destroy(struct flow_table *table) 277 { 278 struct table_instance *ti = rcu_dereference_raw(table->ti); 279 struct table_instance *ufid_ti = rcu_dereference_raw(table->ufid_ti); 280 281 table_instance_destroy(ti, ufid_ti, false); 282 } 283 284 struct sw_flow *ovs_flow_tbl_dump_next(struct table_instance *ti, 285 u32 *bucket, u32 *last) 286 { 287 struct sw_flow *flow; 288 struct hlist_head *head; 289 int ver; 290 int i; 291 292 ver = ti->node_ver; 293 while (*bucket < ti->n_buckets) { 294 i = 0; 295 head = flex_array_get(ti->buckets, *bucket); 296 hlist_for_each_entry_rcu(flow, head, flow_table.node[ver]) { 297 if (i < *last) { 298 i++; 299 continue; 300 } 301 *last = i + 1; 302 return flow; 303 } 304 (*bucket)++; 305 *last = 0; 306 } 307 308 return NULL; 309 } 310 311 static struct hlist_head *find_bucket(struct table_instance *ti, u32 hash) 312 { 313 hash = jhash_1word(hash, ti->hash_seed); 314 return flex_array_get(ti->buckets, 315 (hash & (ti->n_buckets - 1))); 316 } 317 318 static void table_instance_insert(struct table_instance *ti, 319 struct sw_flow *flow) 320 { 321 struct hlist_head *head; 322 323 head = find_bucket(ti, flow->flow_table.hash); 324 hlist_add_head_rcu(&flow->flow_table.node[ti->node_ver], head); 325 } 326 327 static void ufid_table_instance_insert(struct table_instance *ti, 328 struct sw_flow *flow) 329 { 330 struct hlist_head *head; 331 332 head = find_bucket(ti, flow->ufid_table.hash); 333 hlist_add_head_rcu(&flow->ufid_table.node[ti->node_ver], head); 334 } 335 336 static void flow_table_copy_flows(struct table_instance *old, 337 struct table_instance *new, bool ufid) 338 { 339 int old_ver; 340 int i; 341 342 old_ver = old->node_ver; 343 new->node_ver = !old_ver; 344 345 /* Insert in new table. */ 346 for (i = 0; i < old->n_buckets; i++) { 347 struct sw_flow *flow; 348 struct hlist_head *head; 349 350 head = flex_array_get(old->buckets, i); 351 352 if (ufid) 353 hlist_for_each_entry(flow, head, 354 ufid_table.node[old_ver]) 355 ufid_table_instance_insert(new, flow); 356 else 357 hlist_for_each_entry(flow, head, 358 flow_table.node[old_ver]) 359 table_instance_insert(new, flow); 360 } 361 362 old->keep_flows = true; 363 } 364 365 static struct table_instance *table_instance_rehash(struct table_instance *ti, 366 int n_buckets, bool ufid) 367 { 368 struct table_instance *new_ti; 369 370 new_ti = table_instance_alloc(n_buckets); 371 if (!new_ti) 372 return NULL; 373 374 flow_table_copy_flows(ti, new_ti, ufid); 375 376 return new_ti; 377 } 378 379 int ovs_flow_tbl_flush(struct flow_table *flow_table) 380 { 381 struct table_instance *old_ti, *new_ti; 382 struct table_instance *old_ufid_ti, *new_ufid_ti; 383 384 new_ti = table_instance_alloc(TBL_MIN_BUCKETS); 385 if (!new_ti) 386 return -ENOMEM; 387 new_ufid_ti = table_instance_alloc(TBL_MIN_BUCKETS); 388 if (!new_ufid_ti) 389 goto err_free_ti; 390 391 old_ti = ovsl_dereference(flow_table->ti); 392 old_ufid_ti = ovsl_dereference(flow_table->ufid_ti); 393 394 rcu_assign_pointer(flow_table->ti, new_ti); 395 rcu_assign_pointer(flow_table->ufid_ti, new_ufid_ti); 396 flow_table->last_rehash = jiffies; 397 flow_table->count = 0; 398 flow_table->ufid_count = 0; 399 400 table_instance_destroy(old_ti, old_ufid_ti, true); 401 return 0; 402 403 err_free_ti: 404 __table_instance_destroy(new_ti); 405 return -ENOMEM; 406 } 407 408 static u32 flow_hash(const struct sw_flow_key *key, 409 const struct sw_flow_key_range *range) 410 { 411 int key_start = range->start; 412 int key_end = range->end; 413 const u32 *hash_key = (const u32 *)((const u8 *)key + key_start); 414 int hash_u32s = (key_end - key_start) >> 2; 415 416 /* Make sure number of hash bytes are multiple of u32. */ 417 BUILD_BUG_ON(sizeof(long) % sizeof(u32)); 418 419 return jhash2(hash_key, hash_u32s, 0); 420 } 421 422 static int flow_key_start(const struct sw_flow_key *key) 423 { 424 if (key->tun_proto) 425 return 0; 426 else 427 return rounddown(offsetof(struct sw_flow_key, phy), 428 sizeof(long)); 429 } 430 431 static bool cmp_key(const struct sw_flow_key *key1, 432 const struct sw_flow_key *key2, 433 int key_start, int key_end) 434 { 435 const long *cp1 = (const long *)((const u8 *)key1 + key_start); 436 const long *cp2 = (const long *)((const u8 *)key2 + key_start); 437 long diffs = 0; 438 int i; 439 440 for (i = key_start; i < key_end; i += sizeof(long)) 441 diffs |= *cp1++ ^ *cp2++; 442 443 return diffs == 0; 444 } 445 446 static bool flow_cmp_masked_key(const struct sw_flow *flow, 447 const struct sw_flow_key *key, 448 const struct sw_flow_key_range *range) 449 { 450 return cmp_key(&flow->key, key, range->start, range->end); 451 } 452 453 static bool ovs_flow_cmp_unmasked_key(const struct sw_flow *flow, 454 const struct sw_flow_match *match) 455 { 456 struct sw_flow_key *key = match->key; 457 int key_start = flow_key_start(key); 458 int key_end = match->range.end; 459 460 BUG_ON(ovs_identifier_is_ufid(&flow->id)); 461 return cmp_key(flow->id.unmasked_key, key, key_start, key_end); 462 } 463 464 static struct sw_flow *masked_flow_lookup(struct table_instance *ti, 465 const struct sw_flow_key *unmasked, 466 const struct sw_flow_mask *mask) 467 { 468 struct sw_flow *flow; 469 struct hlist_head *head; 470 u32 hash; 471 struct sw_flow_key masked_key; 472 473 ovs_flow_mask_key(&masked_key, unmasked, false, mask); 474 hash = flow_hash(&masked_key, &mask->range); 475 head = find_bucket(ti, hash); 476 hlist_for_each_entry_rcu(flow, head, flow_table.node[ti->node_ver]) { 477 if (flow->mask == mask && flow->flow_table.hash == hash && 478 flow_cmp_masked_key(flow, &masked_key, &mask->range)) 479 return flow; 480 } 481 return NULL; 482 } 483 484 struct sw_flow *ovs_flow_tbl_lookup_stats(struct flow_table *tbl, 485 const struct sw_flow_key *key, 486 u32 *n_mask_hit) 487 { 488 struct table_instance *ti = rcu_dereference_ovsl(tbl->ti); 489 struct sw_flow_mask *mask; 490 struct sw_flow *flow; 491 492 *n_mask_hit = 0; 493 list_for_each_entry_rcu(mask, &tbl->mask_list, list) { 494 (*n_mask_hit)++; 495 flow = masked_flow_lookup(ti, key, mask); 496 if (flow) /* Found */ 497 return flow; 498 } 499 return NULL; 500 } 501 502 struct sw_flow *ovs_flow_tbl_lookup(struct flow_table *tbl, 503 const struct sw_flow_key *key) 504 { 505 u32 __always_unused n_mask_hit; 506 507 return ovs_flow_tbl_lookup_stats(tbl, key, &n_mask_hit); 508 } 509 510 struct sw_flow *ovs_flow_tbl_lookup_exact(struct flow_table *tbl, 511 const struct sw_flow_match *match) 512 { 513 struct table_instance *ti = rcu_dereference_ovsl(tbl->ti); 514 struct sw_flow_mask *mask; 515 struct sw_flow *flow; 516 517 /* Always called under ovs-mutex. */ 518 list_for_each_entry(mask, &tbl->mask_list, list) { 519 flow = masked_flow_lookup(ti, match->key, mask); 520 if (flow && ovs_identifier_is_key(&flow->id) && 521 ovs_flow_cmp_unmasked_key(flow, match)) 522 return flow; 523 } 524 return NULL; 525 } 526 527 static u32 ufid_hash(const struct sw_flow_id *sfid) 528 { 529 return jhash(sfid->ufid, sfid->ufid_len, 0); 530 } 531 532 static bool ovs_flow_cmp_ufid(const struct sw_flow *flow, 533 const struct sw_flow_id *sfid) 534 { 535 if (flow->id.ufid_len != sfid->ufid_len) 536 return false; 537 538 return !memcmp(flow->id.ufid, sfid->ufid, sfid->ufid_len); 539 } 540 541 bool ovs_flow_cmp(const struct sw_flow *flow, const struct sw_flow_match *match) 542 { 543 if (ovs_identifier_is_ufid(&flow->id)) 544 return flow_cmp_masked_key(flow, match->key, &match->range); 545 546 return ovs_flow_cmp_unmasked_key(flow, match); 547 } 548 549 struct sw_flow *ovs_flow_tbl_lookup_ufid(struct flow_table *tbl, 550 const struct sw_flow_id *ufid) 551 { 552 struct table_instance *ti = rcu_dereference_ovsl(tbl->ufid_ti); 553 struct sw_flow *flow; 554 struct hlist_head *head; 555 u32 hash; 556 557 hash = ufid_hash(ufid); 558 head = find_bucket(ti, hash); 559 hlist_for_each_entry_rcu(flow, head, ufid_table.node[ti->node_ver]) { 560 if (flow->ufid_table.hash == hash && 561 ovs_flow_cmp_ufid(flow, ufid)) 562 return flow; 563 } 564 return NULL; 565 } 566 567 int ovs_flow_tbl_num_masks(const struct flow_table *table) 568 { 569 struct sw_flow_mask *mask; 570 int num = 0; 571 572 list_for_each_entry(mask, &table->mask_list, list) 573 num++; 574 575 return num; 576 } 577 578 static struct table_instance *table_instance_expand(struct table_instance *ti, 579 bool ufid) 580 { 581 return table_instance_rehash(ti, ti->n_buckets * 2, ufid); 582 } 583 584 /* Remove 'mask' from the mask list, if it is not needed any more. */ 585 static void flow_mask_remove(struct flow_table *tbl, struct sw_flow_mask *mask) 586 { 587 if (mask) { 588 /* ovs-lock is required to protect mask-refcount and 589 * mask list. 590 */ 591 ASSERT_OVSL(); 592 BUG_ON(!mask->ref_count); 593 mask->ref_count--; 594 595 if (!mask->ref_count) { 596 list_del_rcu(&mask->list); 597 kfree_rcu(mask, rcu); 598 } 599 } 600 } 601 602 /* Must be called with OVS mutex held. */ 603 void ovs_flow_tbl_remove(struct flow_table *table, struct sw_flow *flow) 604 { 605 struct table_instance *ti = ovsl_dereference(table->ti); 606 struct table_instance *ufid_ti = ovsl_dereference(table->ufid_ti); 607 608 BUG_ON(table->count == 0); 609 hlist_del_rcu(&flow->flow_table.node[ti->node_ver]); 610 table->count--; 611 if (ovs_identifier_is_ufid(&flow->id)) { 612 hlist_del_rcu(&flow->ufid_table.node[ufid_ti->node_ver]); 613 table->ufid_count--; 614 } 615 616 /* RCU delete the mask. 'flow->mask' is not NULLed, as it should be 617 * accessible as long as the RCU read lock is held. 618 */ 619 flow_mask_remove(table, flow->mask); 620 } 621 622 static struct sw_flow_mask *mask_alloc(void) 623 { 624 struct sw_flow_mask *mask; 625 626 mask = kmalloc(sizeof(*mask), GFP_KERNEL); 627 if (mask) 628 mask->ref_count = 1; 629 630 return mask; 631 } 632 633 static bool mask_equal(const struct sw_flow_mask *a, 634 const struct sw_flow_mask *b) 635 { 636 const u8 *a_ = (const u8 *)&a->key + a->range.start; 637 const u8 *b_ = (const u8 *)&b->key + b->range.start; 638 639 return (a->range.end == b->range.end) 640 && (a->range.start == b->range.start) 641 && (memcmp(a_, b_, range_n_bytes(&a->range)) == 0); 642 } 643 644 static struct sw_flow_mask *flow_mask_find(const struct flow_table *tbl, 645 const struct sw_flow_mask *mask) 646 { 647 struct list_head *ml; 648 649 list_for_each(ml, &tbl->mask_list) { 650 struct sw_flow_mask *m; 651 m = container_of(ml, struct sw_flow_mask, list); 652 if (mask_equal(mask, m)) 653 return m; 654 } 655 656 return NULL; 657 } 658 659 /* Add 'mask' into the mask list, if it is not already there. */ 660 static int flow_mask_insert(struct flow_table *tbl, struct sw_flow *flow, 661 const struct sw_flow_mask *new) 662 { 663 struct sw_flow_mask *mask; 664 mask = flow_mask_find(tbl, new); 665 if (!mask) { 666 /* Allocate a new mask if none exsits. */ 667 mask = mask_alloc(); 668 if (!mask) 669 return -ENOMEM; 670 mask->key = new->key; 671 mask->range = new->range; 672 list_add_rcu(&mask->list, &tbl->mask_list); 673 } else { 674 BUG_ON(!mask->ref_count); 675 mask->ref_count++; 676 } 677 678 flow->mask = mask; 679 return 0; 680 } 681 682 /* Must be called with OVS mutex held. */ 683 static void flow_key_insert(struct flow_table *table, struct sw_flow *flow) 684 { 685 struct table_instance *new_ti = NULL; 686 struct table_instance *ti; 687 688 flow->flow_table.hash = flow_hash(&flow->key, &flow->mask->range); 689 ti = ovsl_dereference(table->ti); 690 table_instance_insert(ti, flow); 691 table->count++; 692 693 /* Expand table, if necessary, to make room. */ 694 if (table->count > ti->n_buckets) 695 new_ti = table_instance_expand(ti, false); 696 else if (time_after(jiffies, table->last_rehash + REHASH_INTERVAL)) 697 new_ti = table_instance_rehash(ti, ti->n_buckets, false); 698 699 if (new_ti) { 700 rcu_assign_pointer(table->ti, new_ti); 701 call_rcu(&ti->rcu, flow_tbl_destroy_rcu_cb); 702 table->last_rehash = jiffies; 703 } 704 } 705 706 /* Must be called with OVS mutex held. */ 707 static void flow_ufid_insert(struct flow_table *table, struct sw_flow *flow) 708 { 709 struct table_instance *ti; 710 711 flow->ufid_table.hash = ufid_hash(&flow->id); 712 ti = ovsl_dereference(table->ufid_ti); 713 ufid_table_instance_insert(ti, flow); 714 table->ufid_count++; 715 716 /* Expand table, if necessary, to make room. */ 717 if (table->ufid_count > ti->n_buckets) { 718 struct table_instance *new_ti; 719 720 new_ti = table_instance_expand(ti, true); 721 if (new_ti) { 722 rcu_assign_pointer(table->ufid_ti, new_ti); 723 call_rcu(&ti->rcu, flow_tbl_destroy_rcu_cb); 724 } 725 } 726 } 727 728 /* Must be called with OVS mutex held. */ 729 int ovs_flow_tbl_insert(struct flow_table *table, struct sw_flow *flow, 730 const struct sw_flow_mask *mask) 731 { 732 int err; 733 734 err = flow_mask_insert(table, flow, mask); 735 if (err) 736 return err; 737 flow_key_insert(table, flow); 738 if (ovs_identifier_is_ufid(&flow->id)) 739 flow_ufid_insert(table, flow); 740 741 return 0; 742 } 743 744 /* Initializes the flow module. 745 * Returns zero if successful or a negative error code. */ 746 int ovs_flow_init(void) 747 { 748 BUILD_BUG_ON(__alignof__(struct sw_flow_key) % __alignof__(long)); 749 BUILD_BUG_ON(sizeof(struct sw_flow_key) % sizeof(long)); 750 751 flow_cache = kmem_cache_create("sw_flow", sizeof(struct sw_flow) 752 + (nr_cpu_ids 753 * sizeof(struct flow_stats *)), 754 0, 0, NULL); 755 if (flow_cache == NULL) 756 return -ENOMEM; 757 758 flow_stats_cache 759 = kmem_cache_create("sw_flow_stats", sizeof(struct flow_stats), 760 0, SLAB_HWCACHE_ALIGN, NULL); 761 if (flow_stats_cache == NULL) { 762 kmem_cache_destroy(flow_cache); 763 flow_cache = NULL; 764 return -ENOMEM; 765 } 766 767 return 0; 768 } 769 770 /* Uninitializes the flow module. */ 771 void ovs_flow_exit(void) 772 { 773 kmem_cache_destroy(flow_stats_cache); 774 kmem_cache_destroy(flow_cache); 775 } 776