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e6445719 PS |
1 | /* |
2 | * Copyright (c) 2007-2013 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 <linux/uaccess.h> | |
22 | #include <linux/netdevice.h> | |
23 | #include <linux/etherdevice.h> | |
24 | #include <linux/if_ether.h> | |
25 | #include <linux/if_vlan.h> | |
26 | #include <net/llc_pdu.h> | |
27 | #include <linux/kernel.h> | |
28 | #include <linux/jhash.h> | |
29 | #include <linux/jiffies.h> | |
30 | #include <linux/llc.h> | |
31 | #include <linux/module.h> | |
32 | #include <linux/in.h> | |
33 | #include <linux/rcupdate.h> | |
34 | #include <linux/if_arp.h> | |
35 | #include <linux/ip.h> | |
36 | #include <linux/ipv6.h> | |
37 | #include <linux/sctp.h> | |
38 | #include <linux/tcp.h> | |
39 | #include <linux/udp.h> | |
40 | #include <linux/icmp.h> | |
41 | #include <linux/icmpv6.h> | |
42 | #include <linux/rculist.h> | |
43 | #include <net/ip.h> | |
44 | #include <net/ipv6.h> | |
45 | #include <net/ndisc.h> | |
46 | ||
b637e498 PS |
47 | #include "datapath.h" |
48 | ||
49 | #define TBL_MIN_BUCKETS 1024 | |
50 | #define REHASH_INTERVAL (10 * 60 * HZ) | |
51 | ||
e6445719 PS |
52 | static struct kmem_cache *flow_cache; |
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 | const struct sw_flow_mask *mask) | |
61 | { | |
62 | const long *m = (long *)((u8 *)&mask->key + mask->range.start); | |
63 | const long *s = (long *)((u8 *)src + mask->range.start); | |
64 | long *d = (long *)((u8 *)dst + mask->range.start); | |
65 | int i; | |
66 | ||
67 | /* The memory outside of the 'mask->range' are not set since | |
68 | * further operations on 'dst' only uses contents within | |
69 | * 'mask->range'. | |
70 | */ | |
71 | for (i = 0; i < range_n_bytes(&mask->range); i += sizeof(long)) | |
72 | *d++ = *s++ & *m++; | |
73 | } | |
74 | ||
75 | struct sw_flow *ovs_flow_alloc(void) | |
76 | { | |
77 | struct sw_flow *flow; | |
78 | ||
79 | flow = kmem_cache_alloc(flow_cache, GFP_KERNEL); | |
80 | if (!flow) | |
81 | return ERR_PTR(-ENOMEM); | |
82 | ||
83 | spin_lock_init(&flow->lock); | |
84 | flow->sf_acts = NULL; | |
85 | flow->mask = NULL; | |
86 | ||
87 | return flow; | |
88 | } | |
89 | ||
b637e498 PS |
90 | int ovs_flow_tbl_count(struct flow_table *table) |
91 | { | |
92 | return table->count; | |
93 | } | |
94 | ||
e6445719 PS |
95 | static struct flex_array *alloc_buckets(unsigned int n_buckets) |
96 | { | |
97 | struct flex_array *buckets; | |
98 | int i, err; | |
99 | ||
100 | buckets = flex_array_alloc(sizeof(struct hlist_head), | |
101 | n_buckets, GFP_KERNEL); | |
102 | if (!buckets) | |
103 | return NULL; | |
104 | ||
105 | err = flex_array_prealloc(buckets, 0, n_buckets, GFP_KERNEL); | |
106 | if (err) { | |
107 | flex_array_free(buckets); | |
108 | return NULL; | |
109 | } | |
110 | ||
111 | for (i = 0; i < n_buckets; i++) | |
112 | INIT_HLIST_HEAD((struct hlist_head *) | |
113 | flex_array_get(buckets, i)); | |
114 | ||
115 | return buckets; | |
116 | } | |
117 | ||
118 | static void flow_free(struct sw_flow *flow) | |
119 | { | |
120 | kfree((struct sf_flow_acts __force *)flow->sf_acts); | |
121 | kmem_cache_free(flow_cache, flow); | |
122 | } | |
123 | ||
124 | static void rcu_free_flow_callback(struct rcu_head *rcu) | |
125 | { | |
126 | struct sw_flow *flow = container_of(rcu, struct sw_flow, rcu); | |
127 | ||
128 | flow_free(flow); | |
129 | } | |
130 | ||
618ed0c8 PS |
131 | static void rcu_free_sw_flow_mask_cb(struct rcu_head *rcu) |
132 | { | |
133 | struct sw_flow_mask *mask = container_of(rcu, struct sw_flow_mask, rcu); | |
134 | ||
135 | kfree(mask); | |
136 | } | |
137 | ||
138 | static void flow_mask_del_ref(struct sw_flow_mask *mask, bool deferred) | |
139 | { | |
140 | if (!mask) | |
141 | return; | |
142 | ||
143 | BUG_ON(!mask->ref_count); | |
144 | mask->ref_count--; | |
145 | ||
146 | if (!mask->ref_count) { | |
147 | list_del_rcu(&mask->list); | |
148 | if (deferred) | |
149 | call_rcu(&mask->rcu, rcu_free_sw_flow_mask_cb); | |
150 | else | |
151 | kfree(mask); | |
152 | } | |
153 | } | |
154 | ||
e6445719 PS |
155 | void ovs_flow_free(struct sw_flow *flow, bool deferred) |
156 | { | |
157 | if (!flow) | |
158 | return; | |
159 | ||
618ed0c8 | 160 | flow_mask_del_ref(flow->mask, deferred); |
e6445719 PS |
161 | |
162 | if (deferred) | |
163 | call_rcu(&flow->rcu, rcu_free_flow_callback); | |
164 | else | |
165 | flow_free(flow); | |
166 | } | |
167 | ||
168 | static void free_buckets(struct flex_array *buckets) | |
169 | { | |
170 | flex_array_free(buckets); | |
171 | } | |
172 | ||
b637e498 | 173 | static void __table_instance_destroy(struct table_instance *ti) |
e6445719 PS |
174 | { |
175 | int i; | |
176 | ||
b637e498 | 177 | if (ti->keep_flows) |
e6445719 PS |
178 | goto skip_flows; |
179 | ||
b637e498 | 180 | for (i = 0; i < ti->n_buckets; i++) { |
e6445719 | 181 | struct sw_flow *flow; |
b637e498 | 182 | struct hlist_head *head = flex_array_get(ti->buckets, i); |
e6445719 | 183 | struct hlist_node *n; |
b637e498 | 184 | int ver = ti->node_ver; |
e6445719 PS |
185 | |
186 | hlist_for_each_entry_safe(flow, n, head, hash_node[ver]) { | |
187 | hlist_del(&flow->hash_node[ver]); | |
188 | ovs_flow_free(flow, false); | |
189 | } | |
190 | } | |
191 | ||
e6445719 | 192 | skip_flows: |
b637e498 PS |
193 | free_buckets(ti->buckets); |
194 | kfree(ti); | |
e6445719 PS |
195 | } |
196 | ||
b637e498 | 197 | static struct table_instance *table_instance_alloc(int new_size) |
e6445719 | 198 | { |
b637e498 | 199 | struct table_instance *ti = kmalloc(sizeof(*ti), GFP_KERNEL); |
e6445719 | 200 | |
b637e498 | 201 | if (!ti) |
e6445719 PS |
202 | return NULL; |
203 | ||
b637e498 | 204 | ti->buckets = alloc_buckets(new_size); |
e6445719 | 205 | |
b637e498 PS |
206 | if (!ti->buckets) { |
207 | kfree(ti); | |
e6445719 PS |
208 | return NULL; |
209 | } | |
b637e498 PS |
210 | ti->n_buckets = new_size; |
211 | ti->node_ver = 0; | |
212 | ti->keep_flows = false; | |
213 | get_random_bytes(&ti->hash_seed, sizeof(u32)); | |
e6445719 | 214 | |
b637e498 | 215 | return ti; |
e6445719 PS |
216 | } |
217 | ||
b637e498 | 218 | int ovs_flow_tbl_init(struct flow_table *table) |
e6445719 | 219 | { |
b637e498 | 220 | struct table_instance *ti; |
e6445719 | 221 | |
b637e498 | 222 | ti = table_instance_alloc(TBL_MIN_BUCKETS); |
e6445719 | 223 | |
b637e498 PS |
224 | if (!ti) |
225 | return -ENOMEM; | |
e6445719 | 226 | |
b637e498 PS |
227 | rcu_assign_pointer(table->ti, ti); |
228 | INIT_LIST_HEAD(&table->mask_list); | |
229 | table->last_rehash = jiffies; | |
230 | table->count = 0; | |
231 | return 0; | |
e6445719 PS |
232 | } |
233 | ||
234 | static void flow_tbl_destroy_rcu_cb(struct rcu_head *rcu) | |
235 | { | |
b637e498 | 236 | struct table_instance *ti = container_of(rcu, struct table_instance, rcu); |
e6445719 | 237 | |
b637e498 | 238 | __table_instance_destroy(ti); |
e6445719 PS |
239 | } |
240 | ||
b637e498 | 241 | static void table_instance_destroy(struct table_instance *ti, bool deferred) |
e6445719 | 242 | { |
b637e498 | 243 | if (!ti) |
e6445719 PS |
244 | return; |
245 | ||
246 | if (deferred) | |
b637e498 | 247 | call_rcu(&ti->rcu, flow_tbl_destroy_rcu_cb); |
e6445719 | 248 | else |
b637e498 PS |
249 | __table_instance_destroy(ti); |
250 | } | |
251 | ||
618ed0c8 | 252 | void ovs_flow_tbl_destroy(struct flow_table *table) |
b637e498 PS |
253 | { |
254 | struct table_instance *ti = ovsl_dereference(table->ti); | |
255 | ||
618ed0c8 | 256 | table_instance_destroy(ti, false); |
e6445719 PS |
257 | } |
258 | ||
b637e498 | 259 | struct sw_flow *ovs_flow_tbl_dump_next(struct table_instance *ti, |
e6445719 PS |
260 | u32 *bucket, u32 *last) |
261 | { | |
262 | struct sw_flow *flow; | |
263 | struct hlist_head *head; | |
264 | int ver; | |
265 | int i; | |
266 | ||
b637e498 PS |
267 | ver = ti->node_ver; |
268 | while (*bucket < ti->n_buckets) { | |
e6445719 | 269 | i = 0; |
b637e498 | 270 | head = flex_array_get(ti->buckets, *bucket); |
e6445719 PS |
271 | hlist_for_each_entry_rcu(flow, head, hash_node[ver]) { |
272 | if (i < *last) { | |
273 | i++; | |
274 | continue; | |
275 | } | |
276 | *last = i + 1; | |
277 | return flow; | |
278 | } | |
279 | (*bucket)++; | |
280 | *last = 0; | |
281 | } | |
282 | ||
283 | return NULL; | |
284 | } | |
285 | ||
b637e498 | 286 | static struct hlist_head *find_bucket(struct table_instance *ti, u32 hash) |
e6445719 | 287 | { |
b637e498 PS |
288 | hash = jhash_1word(hash, ti->hash_seed); |
289 | return flex_array_get(ti->buckets, | |
290 | (hash & (ti->n_buckets - 1))); | |
e6445719 PS |
291 | } |
292 | ||
b637e498 | 293 | static void table_instance_insert(struct table_instance *ti, struct sw_flow *flow) |
e6445719 PS |
294 | { |
295 | struct hlist_head *head; | |
296 | ||
b637e498 PS |
297 | head = find_bucket(ti, flow->hash); |
298 | hlist_add_head_rcu(&flow->hash_node[ti->node_ver], head); | |
e6445719 PS |
299 | } |
300 | ||
b637e498 PS |
301 | static void flow_table_copy_flows(struct table_instance *old, |
302 | struct table_instance *new) | |
e6445719 PS |
303 | { |
304 | int old_ver; | |
305 | int i; | |
306 | ||
307 | old_ver = old->node_ver; | |
308 | new->node_ver = !old_ver; | |
309 | ||
310 | /* Insert in new table. */ | |
311 | for (i = 0; i < old->n_buckets; i++) { | |
312 | struct sw_flow *flow; | |
313 | struct hlist_head *head; | |
314 | ||
315 | head = flex_array_get(old->buckets, i); | |
316 | ||
317 | hlist_for_each_entry(flow, head, hash_node[old_ver]) | |
b637e498 | 318 | table_instance_insert(new, flow); |
e6445719 PS |
319 | } |
320 | ||
e6445719 PS |
321 | old->keep_flows = true; |
322 | } | |
323 | ||
b637e498 | 324 | static struct table_instance *table_instance_rehash(struct table_instance *ti, |
e6445719 PS |
325 | int n_buckets) |
326 | { | |
b637e498 | 327 | struct table_instance *new_ti; |
e6445719 | 328 | |
b637e498 PS |
329 | new_ti = table_instance_alloc(n_buckets); |
330 | if (!new_ti) | |
618ed0c8 | 331 | return NULL; |
e6445719 | 332 | |
b637e498 | 333 | flow_table_copy_flows(ti, new_ti); |
e6445719 | 334 | |
b637e498 | 335 | return new_ti; |
e6445719 PS |
336 | } |
337 | ||
b637e498 | 338 | int ovs_flow_tbl_flush(struct flow_table *flow_table) |
e6445719 | 339 | { |
b637e498 PS |
340 | struct table_instance *old_ti; |
341 | struct table_instance *new_ti; | |
e6445719 | 342 | |
b637e498 PS |
343 | old_ti = ovsl_dereference(flow_table->ti); |
344 | new_ti = table_instance_alloc(TBL_MIN_BUCKETS); | |
345 | if (!new_ti) | |
346 | return -ENOMEM; | |
347 | ||
348 | rcu_assign_pointer(flow_table->ti, new_ti); | |
349 | flow_table->last_rehash = jiffies; | |
350 | flow_table->count = 0; | |
351 | ||
352 | table_instance_destroy(old_ti, true); | |
353 | return 0; | |
e6445719 PS |
354 | } |
355 | ||
356 | static u32 flow_hash(const struct sw_flow_key *key, int key_start, | |
357 | int key_end) | |
358 | { | |
359 | u32 *hash_key = (u32 *)((u8 *)key + key_start); | |
360 | int hash_u32s = (key_end - key_start) >> 2; | |
361 | ||
362 | /* Make sure number of hash bytes are multiple of u32. */ | |
363 | BUILD_BUG_ON(sizeof(long) % sizeof(u32)); | |
364 | ||
365 | return jhash2(hash_key, hash_u32s, 0); | |
366 | } | |
367 | ||
368 | static int flow_key_start(const struct sw_flow_key *key) | |
369 | { | |
370 | if (key->tun_key.ipv4_dst) | |
371 | return 0; | |
372 | else | |
373 | return rounddown(offsetof(struct sw_flow_key, phy), | |
374 | sizeof(long)); | |
375 | } | |
376 | ||
377 | static bool cmp_key(const struct sw_flow_key *key1, | |
378 | const struct sw_flow_key *key2, | |
379 | int key_start, int key_end) | |
380 | { | |
381 | const long *cp1 = (long *)((u8 *)key1 + key_start); | |
382 | const long *cp2 = (long *)((u8 *)key2 + key_start); | |
383 | long diffs = 0; | |
384 | int i; | |
385 | ||
386 | for (i = key_start; i < key_end; i += sizeof(long)) | |
387 | diffs |= *cp1++ ^ *cp2++; | |
388 | ||
389 | return diffs == 0; | |
390 | } | |
391 | ||
392 | static bool flow_cmp_masked_key(const struct sw_flow *flow, | |
393 | const struct sw_flow_key *key, | |
394 | int key_start, int key_end) | |
395 | { | |
396 | return cmp_key(&flow->key, key, key_start, key_end); | |
397 | } | |
398 | ||
399 | bool ovs_flow_cmp_unmasked_key(const struct sw_flow *flow, | |
400 | struct sw_flow_match *match) | |
401 | { | |
402 | struct sw_flow_key *key = match->key; | |
403 | int key_start = flow_key_start(key); | |
404 | int key_end = match->range.end; | |
405 | ||
406 | return cmp_key(&flow->unmasked_key, key, key_start, key_end); | |
407 | } | |
408 | ||
b637e498 | 409 | static struct sw_flow *masked_flow_lookup(struct table_instance *ti, |
e6445719 PS |
410 | const struct sw_flow_key *unmasked, |
411 | struct sw_flow_mask *mask) | |
412 | { | |
413 | struct sw_flow *flow; | |
414 | struct hlist_head *head; | |
415 | int key_start = mask->range.start; | |
416 | int key_end = mask->range.end; | |
417 | u32 hash; | |
418 | struct sw_flow_key masked_key; | |
419 | ||
420 | ovs_flow_mask_key(&masked_key, unmasked, mask); | |
421 | hash = flow_hash(&masked_key, key_start, key_end); | |
b637e498 PS |
422 | head = find_bucket(ti, hash); |
423 | hlist_for_each_entry_rcu(flow, head, hash_node[ti->node_ver]) { | |
8ddd0946 | 424 | if (flow->mask == mask && flow->hash == hash && |
e6445719 PS |
425 | flow_cmp_masked_key(flow, &masked_key, |
426 | key_start, key_end)) | |
427 | return flow; | |
428 | } | |
429 | return NULL; | |
430 | } | |
431 | ||
432 | struct sw_flow *ovs_flow_tbl_lookup(struct flow_table *tbl, | |
1bd7116f AZ |
433 | const struct sw_flow_key *key, |
434 | u32 *n_mask_hit) | |
e6445719 | 435 | { |
b637e498 | 436 | struct table_instance *ti = rcu_dereference(tbl->ti); |
e6445719 | 437 | struct sw_flow_mask *mask; |
b637e498 | 438 | struct sw_flow *flow; |
e6445719 | 439 | |
1bd7116f | 440 | *n_mask_hit = 0; |
b637e498 | 441 | list_for_each_entry_rcu(mask, &tbl->mask_list, list) { |
1bd7116f | 442 | (*n_mask_hit)++; |
b637e498 | 443 | flow = masked_flow_lookup(ti, key, mask); |
e6445719 | 444 | if (flow) /* Found */ |
b637e498 | 445 | return flow; |
e6445719 | 446 | } |
b637e498 PS |
447 | return NULL; |
448 | } | |
e6445719 | 449 | |
1bd7116f AZ |
450 | int ovs_flow_tbl_num_masks(const struct flow_table *table) |
451 | { | |
452 | struct sw_flow_mask *mask; | |
453 | int num = 0; | |
454 | ||
455 | list_for_each_entry(mask, &table->mask_list, list) | |
456 | num++; | |
457 | ||
458 | return num; | |
459 | } | |
460 | ||
b637e498 PS |
461 | static struct table_instance *table_instance_expand(struct table_instance *ti) |
462 | { | |
463 | return table_instance_rehash(ti, ti->n_buckets * 2); | |
e6445719 PS |
464 | } |
465 | ||
e6445719 PS |
466 | void ovs_flow_tbl_remove(struct flow_table *table, struct sw_flow *flow) |
467 | { | |
b637e498 PS |
468 | struct table_instance *ti = ovsl_dereference(table->ti); |
469 | ||
e6445719 | 470 | BUG_ON(table->count == 0); |
b637e498 | 471 | hlist_del_rcu(&flow->hash_node[ti->node_ver]); |
e6445719 PS |
472 | table->count--; |
473 | } | |
474 | ||
618ed0c8 | 475 | static struct sw_flow_mask *mask_alloc(void) |
e6445719 PS |
476 | { |
477 | struct sw_flow_mask *mask; | |
478 | ||
479 | mask = kmalloc(sizeof(*mask), GFP_KERNEL); | |
480 | if (mask) | |
481 | mask->ref_count = 0; | |
482 | ||
483 | return mask; | |
484 | } | |
485 | ||
618ed0c8 | 486 | static void mask_add_ref(struct sw_flow_mask *mask) |
e6445719 PS |
487 | { |
488 | mask->ref_count++; | |
489 | } | |
490 | ||
e6445719 PS |
491 | static bool mask_equal(const struct sw_flow_mask *a, |
492 | const struct sw_flow_mask *b) | |
493 | { | |
494 | u8 *a_ = (u8 *)&a->key + a->range.start; | |
495 | u8 *b_ = (u8 *)&b->key + b->range.start; | |
496 | ||
497 | return (a->range.end == b->range.end) | |
498 | && (a->range.start == b->range.start) | |
499 | && (memcmp(a_, b_, range_n_bytes(&a->range)) == 0); | |
500 | } | |
501 | ||
618ed0c8 | 502 | static struct sw_flow_mask *flow_mask_find(const struct flow_table *tbl, |
e6445719 PS |
503 | const struct sw_flow_mask *mask) |
504 | { | |
505 | struct list_head *ml; | |
506 | ||
b637e498 | 507 | list_for_each(ml, &tbl->mask_list) { |
e6445719 PS |
508 | struct sw_flow_mask *m; |
509 | m = container_of(ml, struct sw_flow_mask, list); | |
510 | if (mask_equal(mask, m)) | |
511 | return m; | |
512 | } | |
513 | ||
514 | return NULL; | |
515 | } | |
516 | ||
517 | /** | |
518 | * add a new mask into the mask list. | |
519 | * The caller needs to make sure that 'mask' is not the same | |
520 | * as any masks that are already on the list. | |
521 | */ | |
618ed0c8 PS |
522 | static int flow_mask_insert(struct flow_table *tbl, struct sw_flow *flow, |
523 | struct sw_flow_mask *new) | |
524 | { | |
525 | struct sw_flow_mask *mask; | |
526 | mask = flow_mask_find(tbl, new); | |
527 | if (!mask) { | |
528 | /* Allocate a new mask if none exsits. */ | |
529 | mask = mask_alloc(); | |
530 | if (!mask) | |
531 | return -ENOMEM; | |
532 | mask->key = new->key; | |
533 | mask->range = new->range; | |
534 | list_add_rcu(&mask->list, &tbl->mask_list); | |
535 | } | |
536 | ||
537 | mask_add_ref(mask); | |
538 | flow->mask = mask; | |
539 | return 0; | |
540 | } | |
541 | ||
542 | int ovs_flow_tbl_insert(struct flow_table *table, struct sw_flow *flow, | |
543 | struct sw_flow_mask *mask) | |
e6445719 | 544 | { |
618ed0c8 PS |
545 | struct table_instance *new_ti = NULL; |
546 | struct table_instance *ti; | |
547 | int err; | |
548 | ||
549 | err = flow_mask_insert(table, flow, mask); | |
550 | if (err) | |
551 | return err; | |
552 | ||
553 | flow->hash = flow_hash(&flow->key, flow->mask->range.start, | |
554 | flow->mask->range.end); | |
555 | ti = ovsl_dereference(table->ti); | |
556 | table_instance_insert(ti, flow); | |
557 | table->count++; | |
558 | ||
559 | /* Expand table, if necessary, to make room. */ | |
560 | if (table->count > ti->n_buckets) | |
561 | new_ti = table_instance_expand(ti); | |
562 | else if (time_after(jiffies, table->last_rehash + REHASH_INTERVAL)) | |
563 | new_ti = table_instance_rehash(ti, ti->n_buckets); | |
564 | ||
565 | if (new_ti) { | |
566 | rcu_assign_pointer(table->ti, new_ti); | |
567 | table_instance_destroy(ti, true); | |
568 | table->last_rehash = jiffies; | |
569 | } | |
570 | return 0; | |
e6445719 PS |
571 | } |
572 | ||
573 | /* Initializes the flow module. | |
574 | * Returns zero if successful or a negative error code. */ | |
575 | int ovs_flow_init(void) | |
576 | { | |
577 | BUILD_BUG_ON(__alignof__(struct sw_flow_key) % __alignof__(long)); | |
578 | BUILD_BUG_ON(sizeof(struct sw_flow_key) % sizeof(long)); | |
579 | ||
580 | flow_cache = kmem_cache_create("sw_flow", sizeof(struct sw_flow), 0, | |
581 | 0, NULL); | |
582 | if (flow_cache == NULL) | |
583 | return -ENOMEM; | |
584 | ||
585 | return 0; | |
586 | } | |
587 | ||
588 | /* Uninitializes the flow module. */ | |
589 | void ovs_flow_exit(void) | |
590 | { | |
591 | kmem_cache_destroy(flow_cache); | |
592 | } |