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/if_arp.h> 36#include <linux/ip.h> 37#include <linux/ipv6.h> 38#include <linux/sctp.h> 39#include <linux/tcp.h> 40#include <linux/udp.h> 41#include <linux/icmp.h> 42#include <linux/icmpv6.h> 43#include <linux/rculist.h> 44#include <net/ip.h> 45#include <net/ipv6.h> 46#include <net/ndisc.h> 47 48#define TBL_MIN_BUCKETS 1024 49#define REHASH_INTERVAL (10 * 60 * HZ) 50 51static struct kmem_cache *flow_cache; 52struct kmem_cache *flow_stats_cache __read_mostly; 53 54static u16 range_n_bytes(const struct sw_flow_key_range *range) 55{ 56 return range->end - range->start; 57} 58 59void ovs_flow_mask_key(struct sw_flow_key *dst, const struct sw_flow_key *src, 60 bool full, const struct sw_flow_mask *mask) 61{ 62 int start = full ? 0 : mask->range.start; 63 int len = full ? sizeof *dst : range_n_bytes(&mask->range); 64 const long *m = (const long *)((const u8 *)&mask->key + start); 65 const long *s = (const long *)((const u8 *)src + start); 66 long *d = (long *)((u8 *)dst + start); 67 int i; 68 69 /* If 'full' is true then all of 'dst' is fully initialized. Otherwise, 70 * if 'full' is false the memory outside of the 'mask->range' is left 71 * uninitialized. This can be used as an optimization when further 72 * operations on 'dst' only use contents within 'mask->range'. 73 */ 74 for (i = 0; i < len; i += sizeof(long)) 75 *d++ = *s++ & *m++; 76} 77 78struct sw_flow *ovs_flow_alloc(void) 79{ 80 struct sw_flow *flow; 81 struct flow_stats *stats; 82 int node; 83 84 flow = kmem_cache_alloc(flow_cache, GFP_KERNEL); 85 if (!flow) 86 return ERR_PTR(-ENOMEM); 87 88 flow->sf_acts = NULL; 89 flow->mask = NULL; 90 flow->id.unmasked_key = NULL; 91 flow->id.ufid_len = 0; 92 flow->stats_last_writer = NUMA_NO_NODE; 93 94 /* Initialize the default stat node. */ 95 stats = kmem_cache_alloc_node(flow_stats_cache, 96 GFP_KERNEL | __GFP_ZERO, 97 node_online(0) ? 0 : NUMA_NO_NODE); 98 if (!stats) 99 goto err; 100 101 spin_lock_init(&stats->lock); 102 103 RCU_INIT_POINTER(flow->stats[0], stats); 104 105 for_each_node(node) 106 if (node != 0) 107 RCU_INIT_POINTER(flow->stats[node], NULL); 108 109 return flow; 110err: 111 kmem_cache_free(flow_cache, flow); 112 return ERR_PTR(-ENOMEM); 113} 114 115int ovs_flow_tbl_count(const struct flow_table *table) 116{ 117 return table->count; 118} 119 120static struct flex_array *alloc_buckets(unsigned int n_buckets) 121{ 122 struct flex_array *buckets; 123 int i, err; 124 125 buckets = flex_array_alloc(sizeof(struct hlist_head), 126 n_buckets, GFP_KERNEL); 127 if (!buckets) 128 return NULL; 129 130 err = flex_array_prealloc(buckets, 0, n_buckets, GFP_KERNEL); 131 if (err) { 132 flex_array_free(buckets); 133 return NULL; 134 } 135 136 for (i = 0; i < n_buckets; i++) 137 INIT_HLIST_HEAD((struct hlist_head *) 138 flex_array_get(buckets, i)); 139 140 return buckets; 141} 142 143static void flow_free(struct sw_flow *flow) 144{ 145 int node; 146 147 if (ovs_identifier_is_key(&flow->id)) 148 kfree(flow->id.unmasked_key); 149 if (flow->sf_acts) 150 ovs_nla_free_flow_actions((struct sw_flow_actions __force *)flow->sf_acts); 151 for_each_node(node) 152 if (flow->stats[node]) 153 kmem_cache_free(flow_stats_cache, 154 (struct flow_stats __force *)flow->stats[node]); 155 kmem_cache_free(flow_cache, flow); 156} 157 158static void rcu_free_flow_callback(struct rcu_head *rcu) 159{ 160 struct sw_flow *flow = container_of(rcu, struct sw_flow, rcu); 161 162 flow_free(flow); 163} 164 165void ovs_flow_free(struct sw_flow *flow, bool deferred) 166{ 167 if (!flow) 168 return; 169 170 if (deferred) 171 call_rcu(&flow->rcu, rcu_free_flow_callback); 172 else 173 flow_free(flow); 174} 175 176static void free_buckets(struct flex_array *buckets) 177{ 178 flex_array_free(buckets); 179} 180 181 182static void __table_instance_destroy(struct table_instance *ti) 183{ 184 free_buckets(ti->buckets); 185 kfree(ti); 186} 187 188static struct table_instance *table_instance_alloc(int new_size) 189{ 190 struct table_instance *ti = kmalloc(sizeof(*ti), GFP_KERNEL); 191 192 if (!ti) 193 return NULL; 194 195 ti->buckets = alloc_buckets(new_size); 196 197 if (!ti->buckets) { 198 kfree(ti); 199 return NULL; 200 } 201 ti->n_buckets = new_size; 202 ti->node_ver = 0; 203 ti->keep_flows = false; 204 get_random_bytes(&ti->hash_seed, sizeof(u32)); 205 206 return ti; 207} 208 209int ovs_flow_tbl_init(struct flow_table *table) 210{ 211 struct table_instance *ti, *ufid_ti; 212 213 ti = table_instance_alloc(TBL_MIN_BUCKETS); 214 215 if (!ti) 216 return -ENOMEM; 217 218 ufid_ti = table_instance_alloc(TBL_MIN_BUCKETS); 219 if (!ufid_ti) 220 goto free_ti; 221 222 rcu_assign_pointer(table->ti, ti); 223 rcu_assign_pointer(table->ufid_ti, ufid_ti); 224 INIT_LIST_HEAD(&table->mask_list); 225 table->last_rehash = jiffies; 226 table->count = 0; 227 table->ufid_count = 0; 228 return 0; 229 230free_ti: 231 __table_instance_destroy(ti); 232 return -ENOMEM; 233} 234 235static void flow_tbl_destroy_rcu_cb(struct rcu_head *rcu) 236{ 237 struct table_instance *ti = container_of(rcu, struct table_instance, rcu); 238 239 __table_instance_destroy(ti); 240} 241 242static void table_instance_destroy(struct table_instance *ti, 243 struct table_instance *ufid_ti, 244 bool deferred) 245{ 246 int i; 247 248 if (!ti) 249 return; 250 251 BUG_ON(!ufid_ti); 252 if (ti->keep_flows) 253 goto skip_flows; 254 255 for (i = 0; i < ti->n_buckets; i++) { 256 struct sw_flow *flow; 257 struct hlist_head *head = flex_array_get(ti->buckets, i); 258 struct hlist_node *n; 259 int ver = ti->node_ver; 260 int ufid_ver = ufid_ti->node_ver; 261 262 hlist_for_each_entry_safe(flow, n, head, flow_table.node[ver]) { 263 hlist_del_rcu(&flow->flow_table.node[ver]); 264 if (ovs_identifier_is_ufid(&flow->id)) 265 hlist_del_rcu(&flow->ufid_table.node[ufid_ver]); 266 ovs_flow_free(flow, deferred); 267 } 268 } 269 270skip_flows: 271 if (deferred) { 272 call_rcu(&ti->rcu, flow_tbl_destroy_rcu_cb); 273 call_rcu(&ufid_ti->rcu, flow_tbl_destroy_rcu_cb); 274 } else { 275 __table_instance_destroy(ti); 276 __table_instance_destroy(ufid_ti); 277 } 278} 279 280/* No need for locking this function is called from RCU callback or 281 * error path. 282 */ 283void ovs_flow_tbl_destroy(struct flow_table *table) 284{ 285 struct table_instance *ti = rcu_dereference_raw(table->ti); 286 struct table_instance *ufid_ti = rcu_dereference_raw(table->ufid_ti); 287 288 table_instance_destroy(ti, ufid_ti, false); 289} 290 291struct sw_flow *ovs_flow_tbl_dump_next(struct table_instance *ti, 292 u32 *bucket, u32 *last) 293{ 294 struct sw_flow *flow; 295 struct hlist_head *head; 296 int ver; 297 int i; 298 299 ver = ti->node_ver; 300 while (*bucket < ti->n_buckets) { 301 i = 0; 302 head = flex_array_get(ti->buckets, *bucket); 303 hlist_for_each_entry_rcu(flow, head, flow_table.node[ver]) { 304 if (i < *last) { 305 i++; 306 continue; 307 } 308 *last = i + 1; 309 return flow; 310 } 311 (*bucket)++; 312 *last = 0; 313 } 314 315 return NULL; 316} 317 318static struct hlist_head *find_bucket(struct table_instance *ti, u32 hash) 319{ 320 hash = jhash_1word(hash, ti->hash_seed); 321 return flex_array_get(ti->buckets, 322 (hash & (ti->n_buckets - 1))); 323} 324 325static void table_instance_insert(struct table_instance *ti, 326 struct sw_flow *flow) 327{ 328 struct hlist_head *head; 329 330 head = find_bucket(ti, flow->flow_table.hash); 331 hlist_add_head_rcu(&flow->flow_table.node[ti->node_ver], head); 332} 333 334static void ufid_table_instance_insert(struct table_instance *ti, 335 struct sw_flow *flow) 336{ 337 struct hlist_head *head; 338 339 head = find_bucket(ti, flow->ufid_table.hash); 340 hlist_add_head_rcu(&flow->ufid_table.node[ti->node_ver], head); 341} 342 343static void flow_table_copy_flows(struct table_instance *old, 344 struct table_instance *new, bool ufid) 345{ 346 int old_ver; 347 int i; 348 349 old_ver = old->node_ver; 350 new->node_ver = !old_ver; 351 352 /* Insert in new table. */ 353 for (i = 0; i < old->n_buckets; i++) { 354 struct sw_flow *flow; 355 struct hlist_head *head; 356 357 head = flex_array_get(old->buckets, i); 358 359 if (ufid) 360 hlist_for_each_entry(flow, head, 361 ufid_table.node[old_ver]) 362 ufid_table_instance_insert(new, flow); 363 else 364 hlist_for_each_entry(flow, head, 365 flow_table.node[old_ver]) 366 table_instance_insert(new, flow); 367 } 368 369 old->keep_flows = true; 370} 371 372static struct table_instance *table_instance_rehash(struct table_instance *ti, 373 int n_buckets, bool ufid) 374{ 375 struct table_instance *new_ti; 376 377 new_ti = table_instance_alloc(n_buckets); 378 if (!new_ti) 379 return NULL; 380 381 flow_table_copy_flows(ti, new_ti, ufid); 382 383 return new_ti; 384} 385 386int ovs_flow_tbl_flush(struct flow_table *flow_table) 387{ 388 struct table_instance *old_ti, *new_ti; 389 struct table_instance *old_ufid_ti, *new_ufid_ti; 390 391 new_ti = table_instance_alloc(TBL_MIN_BUCKETS); 392 if (!new_ti) 393 return -ENOMEM; 394 new_ufid_ti = table_instance_alloc(TBL_MIN_BUCKETS); 395 if (!new_ufid_ti) 396 goto err_free_ti; 397 398 old_ti = ovsl_dereference(flow_table->ti); 399 old_ufid_ti = ovsl_dereference(flow_table->ufid_ti); 400 401 rcu_assign_pointer(flow_table->ti, new_ti); 402 rcu_assign_pointer(flow_table->ufid_ti, new_ufid_ti); 403 flow_table->last_rehash = jiffies; 404 flow_table->count = 0; 405 flow_table->ufid_count = 0; 406 407 table_instance_destroy(old_ti, old_ufid_ti, true); 408 return 0; 409 410err_free_ti: 411 __table_instance_destroy(new_ti); 412 return -ENOMEM; 413} 414 415static u32 flow_hash(const struct sw_flow_key *key, 416 const struct sw_flow_key_range *range) 417{ 418 int key_start = range->start; 419 int key_end = range->end; 420 const u32 *hash_key = (const u32 *)((const u8 *)key + key_start); 421 int hash_u32s = (key_end - key_start) >> 2; 422 423 /* Make sure number of hash bytes are multiple of u32. */ 424 BUILD_BUG_ON(sizeof(long) % sizeof(u32)); 425 426 return jhash2(hash_key, hash_u32s, 0); 427} 428 429static int flow_key_start(const struct sw_flow_key *key) 430{ 431 if (key->tun_proto) 432 return 0; 433 else 434 return rounddown(offsetof(struct sw_flow_key, phy), 435 sizeof(long)); 436} 437 438static bool cmp_key(const struct sw_flow_key *key1, 439 const struct sw_flow_key *key2, 440 int key_start, int key_end) 441{ 442 const long *cp1 = (const long *)((const u8 *)key1 + key_start); 443 const long *cp2 = (const long *)((const u8 *)key2 + key_start); 444 long diffs = 0; 445 int i; 446 447 for (i = key_start; i < key_end; i += sizeof(long)) 448 diffs |= *cp1++ ^ *cp2++; 449 450 return diffs == 0; 451} 452 453static bool flow_cmp_masked_key(const struct sw_flow *flow, 454 const struct sw_flow_key *key, 455 const struct sw_flow_key_range *range) 456{ 457 return cmp_key(&flow->key, key, range->start, range->end); 458} 459 460static bool ovs_flow_cmp_unmasked_key(const struct sw_flow *flow, 461 const struct sw_flow_match *match) 462{ 463 struct sw_flow_key *key = match->key; 464 int key_start = flow_key_start(key); 465 int key_end = match->range.end; 466 467 BUG_ON(ovs_identifier_is_ufid(&flow->id)); 468 return cmp_key(flow->id.unmasked_key, key, key_start, key_end); 469} 470 471static struct sw_flow *masked_flow_lookup(struct table_instance *ti, 472 const struct sw_flow_key *unmasked, 473 const struct sw_flow_mask *mask) 474{ 475 struct sw_flow *flow; 476 struct hlist_head *head; 477 u32 hash; 478 struct sw_flow_key masked_key; 479 480 ovs_flow_mask_key(&masked_key, unmasked, false, mask); 481 hash = flow_hash(&masked_key, &mask->range); 482 head = find_bucket(ti, hash); 483 hlist_for_each_entry_rcu(flow, head, flow_table.node[ti->node_ver]) { 484 if (flow->mask == mask && flow->flow_table.hash == hash && 485 flow_cmp_masked_key(flow, &masked_key, &mask->range)) 486 return flow; 487 } 488 return NULL; 489} 490 491struct sw_flow *ovs_flow_tbl_lookup_stats(struct flow_table *tbl, 492 const struct sw_flow_key *key, 493 u32 *n_mask_hit) 494{ 495 struct table_instance *ti = rcu_dereference_ovsl(tbl->ti); 496 struct sw_flow_mask *mask; 497 struct sw_flow *flow; 498 499 *n_mask_hit = 0; 500 list_for_each_entry_rcu(mask, &tbl->mask_list, list) { 501 (*n_mask_hit)++; 502 flow = masked_flow_lookup(ti, key, mask); 503 if (flow) /* Found */ 504 return flow; 505 } 506 return NULL; 507} 508 509struct sw_flow *ovs_flow_tbl_lookup(struct flow_table *tbl, 510 const struct sw_flow_key *key) 511{ 512 u32 __always_unused n_mask_hit; 513 514 return ovs_flow_tbl_lookup_stats(tbl, key, &n_mask_hit); 515} 516 517struct sw_flow *ovs_flow_tbl_lookup_exact(struct flow_table *tbl, 518 const struct sw_flow_match *match) 519{ 520 struct table_instance *ti = rcu_dereference_ovsl(tbl->ti); 521 struct sw_flow_mask *mask; 522 struct sw_flow *flow; 523 524 /* Always called under ovs-mutex. */ 525 list_for_each_entry(mask, &tbl->mask_list, list) { 526 flow = masked_flow_lookup(ti, match->key, mask); 527 if (flow && ovs_identifier_is_key(&flow->id) && 528 ovs_flow_cmp_unmasked_key(flow, match)) 529 return flow; 530 } 531 return NULL; 532} 533 534static u32 ufid_hash(const struct sw_flow_id *sfid) 535{ 536 return jhash(sfid->ufid, sfid->ufid_len, 0); 537} 538 539static bool ovs_flow_cmp_ufid(const struct sw_flow *flow, 540 const struct sw_flow_id *sfid) 541{ 542 if (flow->id.ufid_len != sfid->ufid_len) 543 return false; 544 545 return !memcmp(flow->id.ufid, sfid->ufid, sfid->ufid_len); 546} 547 548bool ovs_flow_cmp(const struct sw_flow *flow, const struct sw_flow_match *match) 549{ 550 if (ovs_identifier_is_ufid(&flow->id)) 551 return flow_cmp_masked_key(flow, match->key, &match->range); 552 553 return ovs_flow_cmp_unmasked_key(flow, match); 554} 555 556struct sw_flow *ovs_flow_tbl_lookup_ufid(struct flow_table *tbl, 557 const struct sw_flow_id *ufid) 558{ 559 struct table_instance *ti = rcu_dereference_ovsl(tbl->ufid_ti); 560 struct sw_flow *flow; 561 struct hlist_head *head; 562 u32 hash; 563 564 hash = ufid_hash(ufid); 565 head = find_bucket(ti, hash); 566 hlist_for_each_entry_rcu(flow, head, ufid_table.node[ti->node_ver]) { 567 if (flow->ufid_table.hash == hash && 568 ovs_flow_cmp_ufid(flow, ufid)) 569 return flow; 570 } 571 return NULL; 572} 573 574int ovs_flow_tbl_num_masks(const struct flow_table *table) 575{ 576 struct sw_flow_mask *mask; 577 int num = 0; 578 579 list_for_each_entry(mask, &table->mask_list, list) 580 num++; 581 582 return num; 583} 584 585static struct table_instance *table_instance_expand(struct table_instance *ti, 586 bool ufid) 587{ 588 return table_instance_rehash(ti, ti->n_buckets * 2, ufid); 589} 590 591/* Remove 'mask' from the mask list, if it is not needed any more. */ 592static void flow_mask_remove(struct flow_table *tbl, struct sw_flow_mask *mask) 593{ 594 if (mask) { 595 /* ovs-lock is required to protect mask-refcount and 596 * mask list. 597 */ 598 ASSERT_OVSL(); 599 BUG_ON(!mask->ref_count); 600 mask->ref_count--; 601 602 if (!mask->ref_count) { 603 list_del_rcu(&mask->list); 604 kfree_rcu(mask, rcu); 605 } 606 } 607} 608 609/* Must be called with OVS mutex held. */ 610void ovs_flow_tbl_remove(struct flow_table *table, struct sw_flow *flow) 611{ 612 struct table_instance *ti = ovsl_dereference(table->ti); 613 struct table_instance *ufid_ti = ovsl_dereference(table->ufid_ti); 614 615 BUG_ON(table->count == 0); 616 hlist_del_rcu(&flow->flow_table.node[ti->node_ver]); 617 table->count--; 618 if (ovs_identifier_is_ufid(&flow->id)) { 619 hlist_del_rcu(&flow->ufid_table.node[ufid_ti->node_ver]); 620 table->ufid_count--; 621 } 622 623 /* RCU delete the mask. 'flow->mask' is not NULLed, as it should be 624 * accessible as long as the RCU read lock is held. 625 */ 626 flow_mask_remove(table, flow->mask); 627} 628 629static struct sw_flow_mask *mask_alloc(void) 630{ 631 struct sw_flow_mask *mask; 632 633 mask = kmalloc(sizeof(*mask), GFP_KERNEL); 634 if (mask) 635 mask->ref_count = 1; 636 637 return mask; 638} 639 640static bool mask_equal(const struct sw_flow_mask *a, 641 const struct sw_flow_mask *b) 642{ 643 const u8 *a_ = (const u8 *)&a->key + a->range.start; 644 const u8 *b_ = (const u8 *)&b->key + b->range.start; 645 646 return (a->range.end == b->range.end) 647 && (a->range.start == b->range.start) 648 && (memcmp(a_, b_, range_n_bytes(&a->range)) == 0); 649} 650 651static struct sw_flow_mask *flow_mask_find(const struct flow_table *tbl, 652 const struct sw_flow_mask *mask) 653{ 654 struct list_head *ml; 655 656 list_for_each(ml, &tbl->mask_list) { 657 struct sw_flow_mask *m; 658 m = container_of(ml, struct sw_flow_mask, list); 659 if (mask_equal(mask, m)) 660 return m; 661 } 662 663 return NULL; 664} 665 666/* Add 'mask' into the mask list, if it is not already there. */ 667static int flow_mask_insert(struct flow_table *tbl, struct sw_flow *flow, 668 const struct sw_flow_mask *new) 669{ 670 struct sw_flow_mask *mask; 671 mask = flow_mask_find(tbl, new); 672 if (!mask) { 673 /* Allocate a new mask if none exsits. */ 674 mask = mask_alloc(); 675 if (!mask) 676 return -ENOMEM; 677 mask->key = new->key; 678 mask->range = new->range; 679 list_add_rcu(&mask->list, &tbl->mask_list); 680 } else { 681 BUG_ON(!mask->ref_count); 682 mask->ref_count++; 683 } 684 685 flow->mask = mask; 686 return 0; 687} 688 689/* Must be called with OVS mutex held. */ 690static void flow_key_insert(struct flow_table *table, struct sw_flow *flow) 691{ 692 struct table_instance *new_ti = NULL; 693 struct table_instance *ti; 694 695 flow->flow_table.hash = flow_hash(&flow->key, &flow->mask->range); 696 ti = ovsl_dereference(table->ti); 697 table_instance_insert(ti, flow); 698 table->count++; 699 700 /* Expand table, if necessary, to make room. */ 701 if (table->count > ti->n_buckets) 702 new_ti = table_instance_expand(ti, false); 703 else if (time_after(jiffies, table->last_rehash + REHASH_INTERVAL)) 704 new_ti = table_instance_rehash(ti, ti->n_buckets, false); 705 706 if (new_ti) { 707 rcu_assign_pointer(table->ti, new_ti); 708 call_rcu(&ti->rcu, flow_tbl_destroy_rcu_cb); 709 table->last_rehash = jiffies; 710 } 711} 712 713/* Must be called with OVS mutex held. */ 714static void flow_ufid_insert(struct flow_table *table, struct sw_flow *flow) 715{ 716 struct table_instance *ti; 717 718 flow->ufid_table.hash = ufid_hash(&flow->id); 719 ti = ovsl_dereference(table->ufid_ti); 720 ufid_table_instance_insert(ti, flow); 721 table->ufid_count++; 722 723 /* Expand table, if necessary, to make room. */ 724 if (table->ufid_count > ti->n_buckets) { 725 struct table_instance *new_ti; 726 727 new_ti = table_instance_expand(ti, true); 728 if (new_ti) { 729 rcu_assign_pointer(table->ufid_ti, new_ti); 730 call_rcu(&ti->rcu, flow_tbl_destroy_rcu_cb); 731 } 732 } 733} 734 735/* Must be called with OVS mutex held. */ 736int ovs_flow_tbl_insert(struct flow_table *table, struct sw_flow *flow, 737 const struct sw_flow_mask *mask) 738{ 739 int err; 740 741 err = flow_mask_insert(table, flow, mask); 742 if (err) 743 return err; 744 flow_key_insert(table, flow); 745 if (ovs_identifier_is_ufid(&flow->id)) 746 flow_ufid_insert(table, flow); 747 748 return 0; 749} 750 751/* Initializes the flow module. 752 * Returns zero if successful or a negative error code. */ 753int ovs_flow_init(void) 754{ 755 BUILD_BUG_ON(__alignof__(struct sw_flow_key) % __alignof__(long)); 756 BUILD_BUG_ON(sizeof(struct sw_flow_key) % sizeof(long)); 757 758 flow_cache = kmem_cache_create("sw_flow", sizeof(struct sw_flow) 759 + (nr_node_ids 760 * sizeof(struct flow_stats *)), 761 0, 0, NULL); 762 if (flow_cache == NULL) 763 return -ENOMEM; 764 765 flow_stats_cache 766 = kmem_cache_create("sw_flow_stats", sizeof(struct flow_stats), 767 0, SLAB_HWCACHE_ALIGN, NULL); 768 if (flow_stats_cache == NULL) { 769 kmem_cache_destroy(flow_cache); 770 flow_cache = NULL; 771 return -ENOMEM; 772 } 773 774 return 0; 775} 776 777/* Uninitializes the flow module. */ 778void ovs_flow_exit(void) 779{ 780 kmem_cache_destroy(flow_stats_cache); 781 kmem_cache_destroy(flow_cache); 782} 783