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 51 static struct kmem_cache *flow_cache; 52 struct kmem_cache *flow_stats_cache __read_mostly; 53 54 static u16 range_n_bytes(const struct sw_flow_key_range *range) 55 { 56 return range->end - range->start; 57 } 58 59 void 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 78 struct 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, 0); 97 if (!stats) 98 goto err; 99 100 spin_lock_init(&stats->lock); 101 102 RCU_INIT_POINTER(flow->stats[0], stats); 103 104 for_each_node(node) 105 if (node != 0) 106 RCU_INIT_POINTER(flow->stats[node], NULL); 107 108 return flow; 109 err: 110 kmem_cache_free(flow_cache, flow); 111 return ERR_PTR(-ENOMEM); 112 } 113 114 int ovs_flow_tbl_count(const struct flow_table *table) 115 { 116 return table->count; 117 } 118 119 static struct flex_array *alloc_buckets(unsigned int n_buckets) 120 { 121 struct flex_array *buckets; 122 int i, err; 123 124 buckets = flex_array_alloc(sizeof(struct hlist_head), 125 n_buckets, GFP_KERNEL); 126 if (!buckets) 127 return NULL; 128 129 err = flex_array_prealloc(buckets, 0, n_buckets, GFP_KERNEL); 130 if (err) { 131 flex_array_free(buckets); 132 return NULL; 133 } 134 135 for (i = 0; i < n_buckets; i++) 136 INIT_HLIST_HEAD((struct hlist_head *) 137 flex_array_get(buckets, i)); 138 139 return buckets; 140 } 141 142 static void flow_free(struct sw_flow *flow) 143 { 144 int node; 145 146 if (ovs_identifier_is_key(&flow->id)) 147 kfree(flow->id.unmasked_key); 148 if (flow->sf_acts) 149 ovs_nla_free_flow_actions((struct sw_flow_actions __force *)flow->sf_acts); 150 for_each_node(node) 151 if (flow->stats[node]) 152 kmem_cache_free(flow_stats_cache, 153 (struct flow_stats __force *)flow->stats[node]); 154 kmem_cache_free(flow_cache, flow); 155 } 156 157 static void rcu_free_flow_callback(struct rcu_head *rcu) 158 { 159 struct sw_flow *flow = container_of(rcu, struct sw_flow, rcu); 160 161 flow_free(flow); 162 } 163 164 void ovs_flow_free(struct sw_flow *flow, bool deferred) 165 { 166 if (!flow) 167 return; 168 169 if (deferred) 170 call_rcu(&flow->rcu, rcu_free_flow_callback); 171 else 172 flow_free(flow); 173 } 174 175 static void free_buckets(struct flex_array *buckets) 176 { 177 flex_array_free(buckets); 178 } 179 180 181 static void __table_instance_destroy(struct table_instance *ti) 182 { 183 free_buckets(ti->buckets); 184 kfree(ti); 185 } 186 187 static struct table_instance *table_instance_alloc(int new_size) 188 { 189 struct table_instance *ti = kmalloc(sizeof(*ti), GFP_KERNEL); 190 191 if (!ti) 192 return NULL; 193 194 ti->buckets = alloc_buckets(new_size); 195 196 if (!ti->buckets) { 197 kfree(ti); 198 return NULL; 199 } 200 ti->n_buckets = new_size; 201 ti->node_ver = 0; 202 ti->keep_flows = false; 203 get_random_bytes(&ti->hash_seed, sizeof(u32)); 204 205 return ti; 206 } 207 208 int ovs_flow_tbl_init(struct flow_table *table) 209 { 210 struct table_instance *ti, *ufid_ti; 211 212 ti = table_instance_alloc(TBL_MIN_BUCKETS); 213 214 if (!ti) 215 return -ENOMEM; 216 217 ufid_ti = table_instance_alloc(TBL_MIN_BUCKETS); 218 if (!ufid_ti) 219 goto free_ti; 220 221 rcu_assign_pointer(table->ti, ti); 222 rcu_assign_pointer(table->ufid_ti, ufid_ti); 223 INIT_LIST_HEAD(&table->mask_list); 224 table->last_rehash = jiffies; 225 table->count = 0; 226 table->ufid_count = 0; 227 return 0; 228 229 free_ti: 230 __table_instance_destroy(ti); 231 return -ENOMEM; 232 } 233 234 static void flow_tbl_destroy_rcu_cb(struct rcu_head *rcu) 235 { 236 struct table_instance *ti = container_of(rcu, struct table_instance, rcu); 237 238 __table_instance_destroy(ti); 239 } 240 241 static void table_instance_destroy(struct table_instance *ti, 242 struct table_instance *ufid_ti, 243 bool deferred) 244 { 245 int i; 246 247 if (!ti) 248 return; 249 250 BUG_ON(!ufid_ti); 251 if (ti->keep_flows) 252 goto skip_flows; 253 254 for (i = 0; i < ti->n_buckets; i++) { 255 struct sw_flow *flow; 256 struct hlist_head *head = flex_array_get(ti->buckets, i); 257 struct hlist_node *n; 258 int ver = ti->node_ver; 259 int ufid_ver = ufid_ti->node_ver; 260 261 hlist_for_each_entry_safe(flow, n, head, flow_table.node[ver]) { 262 hlist_del_rcu(&flow->flow_table.node[ver]); 263 if (ovs_identifier_is_ufid(&flow->id)) 264 hlist_del_rcu(&flow->ufid_table.node[ufid_ver]); 265 ovs_flow_free(flow, deferred); 266 } 267 } 268 269 skip_flows: 270 if (deferred) { 271 call_rcu(&ti->rcu, flow_tbl_destroy_rcu_cb); 272 call_rcu(&ufid_ti->rcu, flow_tbl_destroy_rcu_cb); 273 } else { 274 __table_instance_destroy(ti); 275 __table_instance_destroy(ufid_ti); 276 } 277 } 278 279 /* No need for locking this function is called from RCU callback or 280 * error path. 281 */ 282 void ovs_flow_tbl_destroy(struct flow_table *table) 283 { 284 struct table_instance *ti = rcu_dereference_raw(table->ti); 285 struct table_instance *ufid_ti = rcu_dereference_raw(table->ufid_ti); 286 287 table_instance_destroy(ti, ufid_ti, false); 288 } 289 290 struct sw_flow *ovs_flow_tbl_dump_next(struct table_instance *ti, 291 u32 *bucket, u32 *last) 292 { 293 struct sw_flow *flow; 294 struct hlist_head *head; 295 int ver; 296 int i; 297 298 ver = ti->node_ver; 299 while (*bucket < ti->n_buckets) { 300 i = 0; 301 head = flex_array_get(ti->buckets, *bucket); 302 hlist_for_each_entry_rcu(flow, head, flow_table.node[ver]) { 303 if (i < *last) { 304 i++; 305 continue; 306 } 307 *last = i + 1; 308 return flow; 309 } 310 (*bucket)++; 311 *last = 0; 312 } 313 314 return NULL; 315 } 316 317 static struct hlist_head *find_bucket(struct table_instance *ti, u32 hash) 318 { 319 hash = jhash_1word(hash, ti->hash_seed); 320 return flex_array_get(ti->buckets, 321 (hash & (ti->n_buckets - 1))); 322 } 323 324 static void table_instance_insert(struct table_instance *ti, 325 struct sw_flow *flow) 326 { 327 struct hlist_head *head; 328 329 head = find_bucket(ti, flow->flow_table.hash); 330 hlist_add_head_rcu(&flow->flow_table.node[ti->node_ver], head); 331 } 332 333 static void ufid_table_instance_insert(struct table_instance *ti, 334 struct sw_flow *flow) 335 { 336 struct hlist_head *head; 337 338 head = find_bucket(ti, flow->ufid_table.hash); 339 hlist_add_head_rcu(&flow->ufid_table.node[ti->node_ver], head); 340 } 341 342 static void flow_table_copy_flows(struct table_instance *old, 343 struct table_instance *new, bool ufid) 344 { 345 int old_ver; 346 int i; 347 348 old_ver = old->node_ver; 349 new->node_ver = !old_ver; 350 351 /* Insert in new table. */ 352 for (i = 0; i < old->n_buckets; i++) { 353 struct sw_flow *flow; 354 struct hlist_head *head; 355 356 head = flex_array_get(old->buckets, i); 357 358 if (ufid) 359 hlist_for_each_entry(flow, head, 360 ufid_table.node[old_ver]) 361 ufid_table_instance_insert(new, flow); 362 else 363 hlist_for_each_entry(flow, head, 364 flow_table.node[old_ver]) 365 table_instance_insert(new, flow); 366 } 367 368 old->keep_flows = true; 369 } 370 371 static struct table_instance *table_instance_rehash(struct table_instance *ti, 372 int n_buckets, bool ufid) 373 { 374 struct table_instance *new_ti; 375 376 new_ti = table_instance_alloc(n_buckets); 377 if (!new_ti) 378 return NULL; 379 380 flow_table_copy_flows(ti, new_ti, ufid); 381 382 return new_ti; 383 } 384 385 int ovs_flow_tbl_flush(struct flow_table *flow_table) 386 { 387 struct table_instance *old_ti, *new_ti; 388 struct table_instance *old_ufid_ti, *new_ufid_ti; 389 390 new_ti = table_instance_alloc(TBL_MIN_BUCKETS); 391 if (!new_ti) 392 return -ENOMEM; 393 new_ufid_ti = table_instance_alloc(TBL_MIN_BUCKETS); 394 if (!new_ufid_ti) 395 goto err_free_ti; 396 397 old_ti = ovsl_dereference(flow_table->ti); 398 old_ufid_ti = ovsl_dereference(flow_table->ufid_ti); 399 400 rcu_assign_pointer(flow_table->ti, new_ti); 401 rcu_assign_pointer(flow_table->ufid_ti, new_ufid_ti); 402 flow_table->last_rehash = jiffies; 403 flow_table->count = 0; 404 flow_table->ufid_count = 0; 405 406 table_instance_destroy(old_ti, old_ufid_ti, true); 407 return 0; 408 409 err_free_ti: 410 __table_instance_destroy(new_ti); 411 return -ENOMEM; 412 } 413 414 static u32 flow_hash(const struct sw_flow_key *key, 415 const struct sw_flow_key_range *range) 416 { 417 int key_start = range->start; 418 int key_end = range->end; 419 const u32 *hash_key = (const u32 *)((const u8 *)key + key_start); 420 int hash_u32s = (key_end - key_start) >> 2; 421 422 /* Make sure number of hash bytes are multiple of u32. */ 423 BUILD_BUG_ON(sizeof(long) % sizeof(u32)); 424 425 return jhash2(hash_key, hash_u32s, 0); 426 } 427 428 static int flow_key_start(const struct sw_flow_key *key) 429 { 430 if (key->tun_key.u.ipv4.dst) 431 return 0; 432 else 433 return rounddown(offsetof(struct sw_flow_key, phy), 434 sizeof(long)); 435 } 436 437 static bool cmp_key(const struct sw_flow_key *key1, 438 const struct sw_flow_key *key2, 439 int key_start, int key_end) 440 { 441 const long *cp1 = (const long *)((const u8 *)key1 + key_start); 442 const long *cp2 = (const long *)((const u8 *)key2 + key_start); 443 long diffs = 0; 444 int i; 445 446 for (i = key_start; i < key_end; i += sizeof(long)) 447 diffs |= *cp1++ ^ *cp2++; 448 449 return diffs == 0; 450 } 451 452 static bool flow_cmp_masked_key(const struct sw_flow *flow, 453 const struct sw_flow_key *key, 454 const struct sw_flow_key_range *range) 455 { 456 return cmp_key(&flow->key, key, range->start, range->end); 457 } 458 459 static bool ovs_flow_cmp_unmasked_key(const struct sw_flow *flow, 460 const struct sw_flow_match *match) 461 { 462 struct sw_flow_key *key = match->key; 463 int key_start = flow_key_start(key); 464 int key_end = match->range.end; 465 466 BUG_ON(ovs_identifier_is_ufid(&flow->id)); 467 return cmp_key(flow->id.unmasked_key, key, key_start, key_end); 468 } 469 470 static struct sw_flow *masked_flow_lookup(struct table_instance *ti, 471 const struct sw_flow_key *unmasked, 472 const struct sw_flow_mask *mask) 473 { 474 struct sw_flow *flow; 475 struct hlist_head *head; 476 u32 hash; 477 struct sw_flow_key masked_key; 478 479 ovs_flow_mask_key(&masked_key, unmasked, false, mask); 480 hash = flow_hash(&masked_key, &mask->range); 481 head = find_bucket(ti, hash); 482 hlist_for_each_entry_rcu(flow, head, flow_table.node[ti->node_ver]) { 483 if (flow->mask == mask && flow->flow_table.hash == hash && 484 flow_cmp_masked_key(flow, &masked_key, &mask->range)) 485 return flow; 486 } 487 return NULL; 488 } 489 490 struct sw_flow *ovs_flow_tbl_lookup_stats(struct flow_table *tbl, 491 const struct sw_flow_key *key, 492 u32 *n_mask_hit) 493 { 494 struct table_instance *ti = rcu_dereference_ovsl(tbl->ti); 495 struct sw_flow_mask *mask; 496 struct sw_flow *flow; 497 498 *n_mask_hit = 0; 499 list_for_each_entry_rcu(mask, &tbl->mask_list, list) { 500 (*n_mask_hit)++; 501 flow = masked_flow_lookup(ti, key, mask); 502 if (flow) /* Found */ 503 return flow; 504 } 505 return NULL; 506 } 507 508 struct sw_flow *ovs_flow_tbl_lookup(struct flow_table *tbl, 509 const struct sw_flow_key *key) 510 { 511 u32 __always_unused n_mask_hit; 512 513 return ovs_flow_tbl_lookup_stats(tbl, key, &n_mask_hit); 514 } 515 516 struct sw_flow *ovs_flow_tbl_lookup_exact(struct flow_table *tbl, 517 const struct sw_flow_match *match) 518 { 519 struct table_instance *ti = rcu_dereference_ovsl(tbl->ti); 520 struct sw_flow_mask *mask; 521 struct sw_flow *flow; 522 523 /* Always called under ovs-mutex. */ 524 list_for_each_entry(mask, &tbl->mask_list, list) { 525 flow = masked_flow_lookup(ti, match->key, mask); 526 if (flow && ovs_identifier_is_key(&flow->id) && 527 ovs_flow_cmp_unmasked_key(flow, match)) 528 return flow; 529 } 530 return NULL; 531 } 532 533 static u32 ufid_hash(const struct sw_flow_id *sfid) 534 { 535 return jhash(sfid->ufid, sfid->ufid_len, 0); 536 } 537 538 static bool ovs_flow_cmp_ufid(const struct sw_flow *flow, 539 const struct sw_flow_id *sfid) 540 { 541 if (flow->id.ufid_len != sfid->ufid_len) 542 return false; 543 544 return !memcmp(flow->id.ufid, sfid->ufid, sfid->ufid_len); 545 } 546 547 bool ovs_flow_cmp(const struct sw_flow *flow, const struct sw_flow_match *match) 548 { 549 if (ovs_identifier_is_ufid(&flow->id)) 550 return flow_cmp_masked_key(flow, match->key, &match->range); 551 552 return ovs_flow_cmp_unmasked_key(flow, match); 553 } 554 555 struct sw_flow *ovs_flow_tbl_lookup_ufid(struct flow_table *tbl, 556 const struct sw_flow_id *ufid) 557 { 558 struct table_instance *ti = rcu_dereference_ovsl(tbl->ufid_ti); 559 struct sw_flow *flow; 560 struct hlist_head *head; 561 u32 hash; 562 563 hash = ufid_hash(ufid); 564 head = find_bucket(ti, hash); 565 hlist_for_each_entry_rcu(flow, head, ufid_table.node[ti->node_ver]) { 566 if (flow->ufid_table.hash == hash && 567 ovs_flow_cmp_ufid(flow, ufid)) 568 return flow; 569 } 570 return NULL; 571 } 572 573 int ovs_flow_tbl_num_masks(const struct flow_table *table) 574 { 575 struct sw_flow_mask *mask; 576 int num = 0; 577 578 list_for_each_entry(mask, &table->mask_list, list) 579 num++; 580 581 return num; 582 } 583 584 static struct table_instance *table_instance_expand(struct table_instance *ti, 585 bool ufid) 586 { 587 return table_instance_rehash(ti, ti->n_buckets * 2, ufid); 588 } 589 590 /* Remove 'mask' from the mask list, if it is not needed any more. */ 591 static void flow_mask_remove(struct flow_table *tbl, struct sw_flow_mask *mask) 592 { 593 if (mask) { 594 /* ovs-lock is required to protect mask-refcount and 595 * mask list. 596 */ 597 ASSERT_OVSL(); 598 BUG_ON(!mask->ref_count); 599 mask->ref_count--; 600 601 if (!mask->ref_count) { 602 list_del_rcu(&mask->list); 603 kfree_rcu(mask, rcu); 604 } 605 } 606 } 607 608 /* Must be called with OVS mutex held. */ 609 void ovs_flow_tbl_remove(struct flow_table *table, struct sw_flow *flow) 610 { 611 struct table_instance *ti = ovsl_dereference(table->ti); 612 struct table_instance *ufid_ti = ovsl_dereference(table->ufid_ti); 613 614 BUG_ON(table->count == 0); 615 hlist_del_rcu(&flow->flow_table.node[ti->node_ver]); 616 table->count--; 617 if (ovs_identifier_is_ufid(&flow->id)) { 618 hlist_del_rcu(&flow->ufid_table.node[ufid_ti->node_ver]); 619 table->ufid_count--; 620 } 621 622 /* RCU delete the mask. 'flow->mask' is not NULLed, as it should be 623 * accessible as long as the RCU read lock is held. 624 */ 625 flow_mask_remove(table, flow->mask); 626 } 627 628 static struct sw_flow_mask *mask_alloc(void) 629 { 630 struct sw_flow_mask *mask; 631 632 mask = kmalloc(sizeof(*mask), GFP_KERNEL); 633 if (mask) 634 mask->ref_count = 1; 635 636 return mask; 637 } 638 639 static bool mask_equal(const struct sw_flow_mask *a, 640 const struct sw_flow_mask *b) 641 { 642 const u8 *a_ = (const u8 *)&a->key + a->range.start; 643 const u8 *b_ = (const u8 *)&b->key + b->range.start; 644 645 return (a->range.end == b->range.end) 646 && (a->range.start == b->range.start) 647 && (memcmp(a_, b_, range_n_bytes(&a->range)) == 0); 648 } 649 650 static struct sw_flow_mask *flow_mask_find(const struct flow_table *tbl, 651 const struct sw_flow_mask *mask) 652 { 653 struct list_head *ml; 654 655 list_for_each(ml, &tbl->mask_list) { 656 struct sw_flow_mask *m; 657 m = container_of(ml, struct sw_flow_mask, list); 658 if (mask_equal(mask, m)) 659 return m; 660 } 661 662 return NULL; 663 } 664 665 /* Add 'mask' into the mask list, if it is not already there. */ 666 static int flow_mask_insert(struct flow_table *tbl, struct sw_flow *flow, 667 const struct sw_flow_mask *new) 668 { 669 struct sw_flow_mask *mask; 670 mask = flow_mask_find(tbl, new); 671 if (!mask) { 672 /* Allocate a new mask if none exsits. */ 673 mask = mask_alloc(); 674 if (!mask) 675 return -ENOMEM; 676 mask->key = new->key; 677 mask->range = new->range; 678 list_add_rcu(&mask->list, &tbl->mask_list); 679 } else { 680 BUG_ON(!mask->ref_count); 681 mask->ref_count++; 682 } 683 684 flow->mask = mask; 685 return 0; 686 } 687 688 /* Must be called with OVS mutex held. */ 689 static void flow_key_insert(struct flow_table *table, struct sw_flow *flow) 690 { 691 struct table_instance *new_ti = NULL; 692 struct table_instance *ti; 693 694 flow->flow_table.hash = flow_hash(&flow->key, &flow->mask->range); 695 ti = ovsl_dereference(table->ti); 696 table_instance_insert(ti, flow); 697 table->count++; 698 699 /* Expand table, if necessary, to make room. */ 700 if (table->count > ti->n_buckets) 701 new_ti = table_instance_expand(ti, false); 702 else if (time_after(jiffies, table->last_rehash + REHASH_INTERVAL)) 703 new_ti = table_instance_rehash(ti, ti->n_buckets, false); 704 705 if (new_ti) { 706 rcu_assign_pointer(table->ti, new_ti); 707 call_rcu(&ti->rcu, flow_tbl_destroy_rcu_cb); 708 table->last_rehash = jiffies; 709 } 710 } 711 712 /* Must be called with OVS mutex held. */ 713 static void flow_ufid_insert(struct flow_table *table, struct sw_flow *flow) 714 { 715 struct table_instance *ti; 716 717 flow->ufid_table.hash = ufid_hash(&flow->id); 718 ti = ovsl_dereference(table->ufid_ti); 719 ufid_table_instance_insert(ti, flow); 720 table->ufid_count++; 721 722 /* Expand table, if necessary, to make room. */ 723 if (table->ufid_count > ti->n_buckets) { 724 struct table_instance *new_ti; 725 726 new_ti = table_instance_expand(ti, true); 727 if (new_ti) { 728 rcu_assign_pointer(table->ufid_ti, new_ti); 729 call_rcu(&ti->rcu, flow_tbl_destroy_rcu_cb); 730 } 731 } 732 } 733 734 /* Must be called with OVS mutex held. */ 735 int ovs_flow_tbl_insert(struct flow_table *table, struct sw_flow *flow, 736 const struct sw_flow_mask *mask) 737 { 738 int err; 739 740 err = flow_mask_insert(table, flow, mask); 741 if (err) 742 return err; 743 flow_key_insert(table, flow); 744 if (ovs_identifier_is_ufid(&flow->id)) 745 flow_ufid_insert(table, flow); 746 747 return 0; 748 } 749 750 /* Initializes the flow module. 751 * Returns zero if successful or a negative error code. */ 752 int ovs_flow_init(void) 753 { 754 BUILD_BUG_ON(__alignof__(struct sw_flow_key) % __alignof__(long)); 755 BUILD_BUG_ON(sizeof(struct sw_flow_key) % sizeof(long)); 756 757 flow_cache = kmem_cache_create("sw_flow", sizeof(struct sw_flow) 758 + (nr_node_ids 759 * sizeof(struct flow_stats *)), 760 0, 0, NULL); 761 if (flow_cache == NULL) 762 return -ENOMEM; 763 764 flow_stats_cache 765 = kmem_cache_create("sw_flow_stats", sizeof(struct flow_stats), 766 0, SLAB_HWCACHE_ALIGN, NULL); 767 if (flow_stats_cache == NULL) { 768 kmem_cache_destroy(flow_cache); 769 flow_cache = NULL; 770 return -ENOMEM; 771 } 772 773 return 0; 774 } 775 776 /* Uninitializes the flow module. */ 777 void ovs_flow_exit(void) 778 { 779 kmem_cache_destroy(flow_stats_cache); 780 kmem_cache_destroy(flow_cache); 781 } 782