2 * Copyright (c) 2007-2013 Nicira, Inc.
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.
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.
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
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>
33 #include <linux/rcupdate.h>
34 #include <linux/if_arp.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>
45 #include <net/ndisc.h>
48 #include "flow_netlink.h"
50 #define TBL_MIN_BUCKETS 1024
51 #define MASK_ARRAY_SIZE_MIN 16
52 #define REHASH_INTERVAL (10 * 60 * HZ)
54 #define MC_HASH_SHIFT 8
55 #define MC_HASH_ENTRIES (1u << MC_HASH_SHIFT)
56 #define MC_HASH_SEGS ((sizeof(uint32_t) * 8) / MC_HASH_SHIFT)
58 static struct kmem_cache *flow_cache;
59 struct kmem_cache *flow_stats_cache __read_mostly;
61 static u16 range_n_bytes(const struct sw_flow_key_range *range)
63 return range->end - range->start;
66 void ovs_flow_mask_key(struct sw_flow_key *dst, const struct sw_flow_key *src,
67 bool full, const struct sw_flow_mask *mask)
69 int start = full ? 0 : mask->range.start;
70 int len = full ? sizeof *dst : range_n_bytes(&mask->range);
71 const long *m = (const long *)((const u8 *)&mask->key + start);
72 const long *s = (const long *)((const u8 *)src + start);
73 long *d = (long *)((u8 *)dst + start);
76 /* If 'full' is true then all of 'dst' is fully initialized. Otherwise,
77 * if 'full' is false the memory outside of the 'mask->range' is left
78 * uninitialized. This can be used as an optimization when further
79 * operations on 'dst' only use contents within 'mask->range'.
81 for (i = 0; i < len; i += sizeof(long))
85 struct sw_flow *ovs_flow_alloc(void)
88 struct flow_stats *stats;
91 flow = kmem_cache_alloc(flow_cache, GFP_KERNEL);
93 return ERR_PTR(-ENOMEM);
97 flow->id.ufid_len = 0;
98 flow->id.unmasked_key = NULL;
99 flow->stats_last_writer = NUMA_NO_NODE;
101 /* Initialize the default stat node. */
102 stats = kmem_cache_alloc_node(flow_stats_cache,
103 GFP_KERNEL | __GFP_ZERO, 0);
107 spin_lock_init(&stats->lock);
109 RCU_INIT_POINTER(flow->stats[0], stats);
113 RCU_INIT_POINTER(flow->stats[node], NULL);
117 kmem_cache_free(flow_cache, flow);
118 return ERR_PTR(-ENOMEM);
121 int ovs_flow_tbl_count(const struct flow_table *table)
126 static struct flex_array *alloc_buckets(unsigned int n_buckets)
128 struct flex_array *buckets;
131 buckets = flex_array_alloc(sizeof(struct hlist_head),
132 n_buckets, GFP_KERNEL);
136 err = flex_array_prealloc(buckets, 0, n_buckets, GFP_KERNEL);
138 flex_array_free(buckets);
142 for (i = 0; i < n_buckets; i++)
143 INIT_HLIST_HEAD((struct hlist_head *)
144 flex_array_get(buckets, i));
149 static void flow_free(struct sw_flow *flow)
153 if (ovs_identifier_is_key(&flow->id))
154 kfree(flow->id.unmasked_key);
156 ovs_nla_free_flow_actions((struct sw_flow_actions __force *)flow->sf_acts);
158 if (flow->stats[node])
159 kmem_cache_free(flow_stats_cache,
160 rcu_dereference_raw(flow->stats[node]));
161 kmem_cache_free(flow_cache, flow);
164 static void rcu_free_flow_callback(struct rcu_head *rcu)
166 struct sw_flow *flow = container_of(rcu, struct sw_flow, rcu);
171 static void rcu_free_sw_flow_mask_cb(struct rcu_head *rcu)
173 struct sw_flow_mask *mask = container_of(rcu, struct sw_flow_mask, rcu);
178 void ovs_flow_free(struct sw_flow *flow, bool deferred)
184 call_rcu(&flow->rcu, rcu_free_flow_callback);
189 static void free_buckets(struct flex_array *buckets)
191 flex_array_free(buckets);
195 static void __table_instance_destroy(struct table_instance *ti)
197 free_buckets(ti->buckets);
201 static struct table_instance *table_instance_alloc(int new_size)
203 struct table_instance *ti = kmalloc(sizeof(*ti), GFP_KERNEL);
208 ti->buckets = alloc_buckets(new_size);
214 ti->n_buckets = new_size;
216 ti->keep_flows = false;
217 get_random_bytes(&ti->hash_seed, sizeof(u32));
222 static void mask_array_rcu_cb(struct rcu_head *rcu)
224 struct mask_array *ma = container_of(rcu, struct mask_array, rcu);
229 static struct mask_array *tbl_mask_array_alloc(int size)
231 struct mask_array *new;
233 size = max(MASK_ARRAY_SIZE_MIN, size);
234 new = kzalloc(sizeof(struct mask_array) +
235 sizeof(struct sw_flow_mask *) * size, GFP_KERNEL);
245 static int tbl_mask_array_realloc(struct flow_table *tbl, int size)
247 struct mask_array *old;
248 struct mask_array *new;
250 new = tbl_mask_array_alloc(size);
254 old = ovsl_dereference(tbl->mask_array);
258 for (i = 0; i < old->max; i++) {
259 if (ovsl_dereference(old->masks[i]))
260 new->masks[count++] = old->masks[i];
265 rcu_assign_pointer(tbl->mask_array, new);
268 call_rcu(&old->rcu, mask_array_rcu_cb);
273 int ovs_flow_tbl_init(struct flow_table *table)
275 struct table_instance *ti, *ufid_ti;
276 struct mask_array *ma;
278 table->mask_cache = __alloc_percpu(sizeof(struct mask_cache_entry) *
279 MC_HASH_ENTRIES, __alignof__(struct mask_cache_entry));
280 if (!table->mask_cache)
283 ma = tbl_mask_array_alloc(MASK_ARRAY_SIZE_MIN);
285 goto free_mask_cache;
287 ti = table_instance_alloc(TBL_MIN_BUCKETS);
289 goto free_mask_array;
291 ufid_ti = table_instance_alloc(TBL_MIN_BUCKETS);
295 rcu_assign_pointer(table->ti, ti);
296 rcu_assign_pointer(table->ufid_ti, ufid_ti);
297 rcu_assign_pointer(table->mask_array, ma);
298 table->last_rehash = jiffies;
300 table->ufid_count = 0;
304 __table_instance_destroy(ti);
308 free_percpu(table->mask_cache);
312 static void flow_tbl_destroy_rcu_cb(struct rcu_head *rcu)
314 struct table_instance *ti = container_of(rcu, struct table_instance, rcu);
316 __table_instance_destroy(ti);
319 static void table_instance_destroy(struct table_instance *ti,
320 struct table_instance *ufid_ti,
332 for (i = 0; i < ti->n_buckets; i++) {
333 struct sw_flow *flow;
334 struct hlist_head *head = flex_array_get(ti->buckets, i);
335 struct hlist_node *n;
336 int ver = ti->node_ver;
337 int ufid_ver = ufid_ti->node_ver;
339 hlist_for_each_entry_safe(flow, n, head, flow_table.node[ver]) {
340 hlist_del_rcu(&flow->flow_table.node[ver]);
341 if (ovs_identifier_is_ufid(&flow->id))
342 hlist_del_rcu(&flow->ufid_table.node[ufid_ver]);
343 ovs_flow_free(flow, deferred);
349 call_rcu(&ti->rcu, flow_tbl_destroy_rcu_cb);
350 call_rcu(&ufid_ti->rcu, flow_tbl_destroy_rcu_cb);
352 __table_instance_destroy(ti);
353 __table_instance_destroy(ufid_ti);
357 /* No need for locking this function is called from RCU callback or
360 void ovs_flow_tbl_destroy(struct flow_table *table)
362 struct table_instance *ti = rcu_dereference_raw(table->ti);
363 struct table_instance *ufid_ti = rcu_dereference_raw(table->ufid_ti);
365 free_percpu(table->mask_cache);
366 kfree(rcu_dereference_raw(table->mask_array));
367 table_instance_destroy(ti, ufid_ti, false);
370 struct sw_flow *ovs_flow_tbl_dump_next(struct table_instance *ti,
371 u32 *bucket, u32 *last)
373 struct sw_flow *flow;
374 struct hlist_head *head;
379 while (*bucket < ti->n_buckets) {
381 head = flex_array_get(ti->buckets, *bucket);
382 hlist_for_each_entry_rcu(flow, head, flow_table.node[ver]) {
397 static struct hlist_head *find_bucket(struct table_instance *ti, u32 hash)
399 hash = jhash_1word(hash, ti->hash_seed);
400 return flex_array_get(ti->buckets,
401 (hash & (ti->n_buckets - 1)));
404 static void table_instance_insert(struct table_instance *ti,
405 struct sw_flow *flow)
407 struct hlist_head *head;
409 head = find_bucket(ti, flow->flow_table.hash);
410 hlist_add_head_rcu(&flow->flow_table.node[ti->node_ver], head);
413 static void ufid_table_instance_insert(struct table_instance *ti,
414 struct sw_flow *flow)
416 struct hlist_head *head;
418 head = find_bucket(ti, flow->ufid_table.hash);
419 hlist_add_head_rcu(&flow->ufid_table.node[ti->node_ver], head);
422 static void flow_table_copy_flows(struct table_instance *old,
423 struct table_instance *new, bool ufid)
428 old_ver = old->node_ver;
429 new->node_ver = !old_ver;
431 /* Insert in new table. */
432 for (i = 0; i < old->n_buckets; i++) {
433 struct sw_flow *flow;
434 struct hlist_head *head;
436 head = flex_array_get(old->buckets, i);
439 hlist_for_each_entry(flow, head,
440 ufid_table.node[old_ver])
441 ufid_table_instance_insert(new, flow);
443 hlist_for_each_entry(flow, head,
444 flow_table.node[old_ver])
445 table_instance_insert(new, flow);
448 old->keep_flows = true;
451 static struct table_instance *table_instance_rehash(struct table_instance *ti,
452 int n_buckets, bool ufid)
454 struct table_instance *new_ti;
456 new_ti = table_instance_alloc(n_buckets);
460 flow_table_copy_flows(ti, new_ti, ufid);
465 int ovs_flow_tbl_flush(struct flow_table *flow_table)
467 struct table_instance *old_ti, *new_ti;
468 struct table_instance *old_ufid_ti, *new_ufid_ti;
470 new_ti = table_instance_alloc(TBL_MIN_BUCKETS);
473 new_ufid_ti = table_instance_alloc(TBL_MIN_BUCKETS);
477 old_ti = ovsl_dereference(flow_table->ti);
478 old_ufid_ti = ovsl_dereference(flow_table->ufid_ti);
480 rcu_assign_pointer(flow_table->ti, new_ti);
481 rcu_assign_pointer(flow_table->ufid_ti, new_ufid_ti);
482 flow_table->last_rehash = jiffies;
483 flow_table->count = 0;
484 flow_table->ufid_count = 0;
486 table_instance_destroy(old_ti, old_ufid_ti, true);
490 __table_instance_destroy(new_ti);
494 static u32 flow_hash(const struct sw_flow_key *key,
495 const struct sw_flow_key_range *range)
497 int key_start = range->start;
498 int key_end = range->end;
499 const u32 *hash_key = (const u32 *)((const u8 *)key + key_start);
500 int hash_u32s = (key_end - key_start) >> 2;
502 /* Make sure number of hash bytes are multiple of u32. */
503 BUILD_BUG_ON(sizeof(long) % sizeof(u32));
505 return jhash2(hash_key, hash_u32s, 0);
508 static int flow_key_start(const struct sw_flow_key *key)
510 if (key->tun_key.u.ipv4.dst)
513 return rounddown(offsetof(struct sw_flow_key, phy),
517 static bool cmp_key(const struct sw_flow_key *key1,
518 const struct sw_flow_key *key2,
519 int key_start, int key_end)
521 const long *cp1 = (const long *)((const u8 *)key1 + key_start);
522 const long *cp2 = (const long *)((const u8 *)key2 + key_start);
526 for (i = key_start; i < key_end; i += sizeof(long))
527 diffs |= *cp1++ ^ *cp2++;
532 static bool flow_cmp_masked_key(const struct sw_flow *flow,
533 const struct sw_flow_key *key,
534 const struct sw_flow_key_range *range)
536 return cmp_key(&flow->key, key, range->start, range->end);
539 static bool ovs_flow_cmp_unmasked_key(const struct sw_flow *flow,
540 const struct sw_flow_match *match)
542 struct sw_flow_key *key = match->key;
543 int key_start = flow_key_start(key);
544 int key_end = match->range.end;
546 BUG_ON(ovs_identifier_is_ufid(&flow->id));
547 return cmp_key(flow->id.unmasked_key, key, key_start, key_end);
550 static struct sw_flow *masked_flow_lookup(struct table_instance *ti,
551 const struct sw_flow_key *unmasked,
552 const struct sw_flow_mask *mask,
555 struct sw_flow *flow;
556 struct hlist_head *head;
558 struct sw_flow_key masked_key;
560 ovs_flow_mask_key(&masked_key, unmasked, false, mask);
561 hash = flow_hash(&masked_key, &mask->range);
562 head = find_bucket(ti, hash);
564 hlist_for_each_entry_rcu(flow, head, flow_table.node[ti->node_ver]) {
565 if (flow->mask == mask && flow->flow_table.hash == hash &&
566 flow_cmp_masked_key(flow, &masked_key, &mask->range))
572 /* Flow lookup does full lookup on flow table. It starts with
573 * mask from index passed in *index.
575 static struct sw_flow *flow_lookup(struct flow_table *tbl,
576 struct table_instance *ti,
577 const struct mask_array *ma,
578 const struct sw_flow_key *key,
582 struct sw_flow_mask *mask;
583 struct sw_flow *flow;
586 if (*index < ma->max) {
587 mask = rcu_dereference_ovsl(ma->masks[*index]);
589 flow = masked_flow_lookup(ti, key, mask, n_mask_hit);
595 for (i = 0; i < ma->max; i++) {
600 mask = rcu_dereference_ovsl(ma->masks[i]);
604 flow = masked_flow_lookup(ti, key, mask, n_mask_hit);
605 if (flow) { /* Found */
615 * mask_cache maps flow to probable mask. This cache is not tightly
616 * coupled cache, It means updates to mask list can result in inconsistent
617 * cache entry in mask cache.
618 * This is per cpu cache and is divided in MC_HASH_SEGS segments.
619 * In case of a hash collision the entry is hashed in next segment.
621 struct sw_flow *ovs_flow_tbl_lookup_stats(struct flow_table *tbl,
622 const struct sw_flow_key *key,
626 struct mask_array *ma = rcu_dereference(tbl->mask_array);
627 struct table_instance *ti = rcu_dereference(tbl->ti);
628 struct mask_cache_entry *entries, *ce;
629 struct sw_flow *flow;
634 if (unlikely(!skb_hash)) {
637 return flow_lookup(tbl, ti, ma, key, n_mask_hit, &mask_index);
640 /* Pre and post recirulation flows usually have the same skb_hash
641 * value. To avoid hash collisions, rehash the 'skb_hash' with
644 skb_hash = jhash_1word(skb_hash, key->recirc_id);
648 entries = this_cpu_ptr(tbl->mask_cache);
650 /* Find the cache entry 'ce' to operate on. */
651 for (seg = 0; seg < MC_HASH_SEGS; seg++) {
652 int index = hash & (MC_HASH_ENTRIES - 1);
653 struct mask_cache_entry *e;
656 if (e->skb_hash == skb_hash) {
657 flow = flow_lookup(tbl, ti, ma, key, n_mask_hit,
664 if (!ce || e->skb_hash < ce->skb_hash)
665 ce = e; /* A better replacement cache candidate. */
667 hash >>= MC_HASH_SHIFT;
670 /* Cache miss, do full lookup. */
671 flow = flow_lookup(tbl, ti, ma, key, n_mask_hit, &ce->mask_index);
673 ce->skb_hash = skb_hash;
678 struct sw_flow *ovs_flow_tbl_lookup(struct flow_table *tbl,
679 const struct sw_flow_key *key)
681 struct table_instance *ti = rcu_dereference_ovsl(tbl->ti);
682 struct mask_array *ma = rcu_dereference_ovsl(tbl->mask_array);
683 u32 __always_unused n_mask_hit;
686 return flow_lookup(tbl, ti, ma, key, &n_mask_hit, &index);
689 struct sw_flow *ovs_flow_tbl_lookup_exact(struct flow_table *tbl,
690 const struct sw_flow_match *match)
692 struct mask_array *ma = ovsl_dereference(tbl->mask_array);
695 /* Always called under ovs-mutex. */
696 for (i = 0; i < ma->max; i++) {
697 struct table_instance *ti = ovsl_dereference(tbl->ti);
698 u32 __always_unused n_mask_hit;
699 struct sw_flow_mask *mask;
700 struct sw_flow *flow;
702 mask = ovsl_dereference(ma->masks[i]);
705 flow = masked_flow_lookup(ti, match->key, mask, &n_mask_hit);
706 if (flow && ovs_identifier_is_key(&flow->id) &&
707 ovs_flow_cmp_unmasked_key(flow, match))
713 static u32 ufid_hash(const struct sw_flow_id *sfid)
715 return jhash(sfid->ufid, sfid->ufid_len, 0);
718 static bool ovs_flow_cmp_ufid(const struct sw_flow *flow,
719 const struct sw_flow_id *sfid)
721 if (flow->id.ufid_len != sfid->ufid_len)
724 return !memcmp(flow->id.ufid, sfid->ufid, sfid->ufid_len);
727 bool ovs_flow_cmp(const struct sw_flow *flow, const struct sw_flow_match *match)
729 if (ovs_identifier_is_ufid(&flow->id))
730 return flow_cmp_masked_key(flow, match->key, &match->range);
732 return ovs_flow_cmp_unmasked_key(flow, match);
735 struct sw_flow *ovs_flow_tbl_lookup_ufid(struct flow_table *tbl,
736 const struct sw_flow_id *ufid)
738 struct table_instance *ti = rcu_dereference_ovsl(tbl->ufid_ti);
739 struct sw_flow *flow;
740 struct hlist_head *head;
743 hash = ufid_hash(ufid);
744 head = find_bucket(ti, hash);
745 hlist_for_each_entry_rcu(flow, head, ufid_table.node[ti->node_ver]) {
746 if (flow->ufid_table.hash == hash &&
747 ovs_flow_cmp_ufid(flow, ufid))
753 int ovs_flow_tbl_num_masks(const struct flow_table *table)
755 struct mask_array *ma;
757 ma = rcu_dereference_ovsl(table->mask_array);
761 static struct table_instance *table_instance_expand(struct table_instance *ti,
764 return table_instance_rehash(ti, ti->n_buckets * 2, ufid);
767 static void tbl_mask_array_delete_mask(struct mask_array *ma,
768 struct sw_flow_mask *mask)
772 /* Remove the deleted mask pointers from the array */
773 for (i = 0; i < ma->max; i++) {
774 if (mask == ovsl_dereference(ma->masks[i])) {
775 RCU_INIT_POINTER(ma->masks[i], NULL);
777 call_rcu(&mask->rcu, rcu_free_sw_flow_mask_cb);
784 /* Remove 'mask' from the mask list, if it is not needed any more. */
785 static void flow_mask_remove(struct flow_table *tbl, struct sw_flow_mask *mask)
788 /* ovs-lock is required to protect mask-refcount and
792 BUG_ON(!mask->ref_count);
795 if (!mask->ref_count) {
796 struct mask_array *ma;
798 ma = ovsl_dereference(tbl->mask_array);
799 tbl_mask_array_delete_mask(ma, mask);
801 /* Shrink the mask array if necessary. */
802 if (ma->max >= (MASK_ARRAY_SIZE_MIN * 2) &&
803 ma->count <= (ma->max / 3))
804 tbl_mask_array_realloc(tbl, ma->max / 2);
810 /* Must be called with OVS mutex held. */
811 void ovs_flow_tbl_remove(struct flow_table *table, struct sw_flow *flow)
813 struct table_instance *ti = ovsl_dereference(table->ti);
814 struct table_instance *ufid_ti = ovsl_dereference(table->ufid_ti);
816 BUG_ON(table->count == 0);
817 hlist_del_rcu(&flow->flow_table.node[ti->node_ver]);
819 if (ovs_identifier_is_ufid(&flow->id)) {
820 hlist_del_rcu(&flow->ufid_table.node[ufid_ti->node_ver]);
824 /* RCU delete the mask. 'flow->mask' is not NULLed, as it should be
825 * accessible as long as the RCU read lock is held.
827 flow_mask_remove(table, flow->mask);
830 static struct sw_flow_mask *mask_alloc(void)
832 struct sw_flow_mask *mask;
834 mask = kmalloc(sizeof(*mask), GFP_KERNEL);
841 static bool mask_equal(const struct sw_flow_mask *a,
842 const struct sw_flow_mask *b)
844 const u8 *a_ = (const u8 *)&a->key + a->range.start;
845 const u8 *b_ = (const u8 *)&b->key + b->range.start;
847 return (a->range.end == b->range.end)
848 && (a->range.start == b->range.start)
849 && (memcmp(a_, b_, range_n_bytes(&a->range)) == 0);
852 static struct sw_flow_mask *flow_mask_find(const struct flow_table *tbl,
853 const struct sw_flow_mask *mask)
855 struct mask_array *ma;
858 ma = ovsl_dereference(tbl->mask_array);
859 for (i = 0; i < ma->max; i++) {
860 struct sw_flow_mask *t;
862 t = ovsl_dereference(ma->masks[i]);
863 if (t && mask_equal(mask, t))
870 /* Add 'mask' into the mask list, if it is not already there. */
871 static int flow_mask_insert(struct flow_table *tbl, struct sw_flow *flow,
872 const struct sw_flow_mask *new)
874 struct sw_flow_mask *mask;
876 mask = flow_mask_find(tbl, new);
878 struct mask_array *ma;
881 /* Allocate a new mask if none exsits. */
886 mask->key = new->key;
887 mask->range = new->range;
889 /* Add mask to mask-list. */
890 ma = ovsl_dereference(tbl->mask_array);
891 if (ma->count >= ma->max) {
894 err = tbl_mask_array_realloc(tbl, ma->max +
895 MASK_ARRAY_SIZE_MIN);
900 ma = ovsl_dereference(tbl->mask_array);
903 for (i = 0; i < ma->max; i++) {
904 struct sw_flow_mask *t;
906 t = ovsl_dereference(ma->masks[i]);
908 rcu_assign_pointer(ma->masks[i], mask);
915 BUG_ON(!mask->ref_count);
923 /* Must be called with OVS mutex held. */
924 static void flow_key_insert(struct flow_table *table, struct sw_flow *flow)
926 struct table_instance *new_ti = NULL;
927 struct table_instance *ti;
929 flow->flow_table.hash = flow_hash(&flow->key, &flow->mask->range);
930 ti = ovsl_dereference(table->ti);
931 table_instance_insert(ti, flow);
934 /* Expand table, if necessary, to make room. */
935 if (table->count > ti->n_buckets)
936 new_ti = table_instance_expand(ti, false);
937 else if (time_after(jiffies, table->last_rehash + REHASH_INTERVAL))
938 new_ti = table_instance_rehash(ti, ti->n_buckets, false);
941 rcu_assign_pointer(table->ti, new_ti);
942 call_rcu(&ti->rcu, flow_tbl_destroy_rcu_cb);
943 table->last_rehash = jiffies;
947 /* Must be called with OVS mutex held. */
948 static void flow_ufid_insert(struct flow_table *table, struct sw_flow *flow)
950 struct table_instance *ti;
952 flow->ufid_table.hash = ufid_hash(&flow->id);
953 ti = ovsl_dereference(table->ufid_ti);
954 ufid_table_instance_insert(ti, flow);
957 /* Expand table, if necessary, to make room. */
958 if (table->ufid_count > ti->n_buckets) {
959 struct table_instance *new_ti;
961 new_ti = table_instance_expand(ti, true);
963 rcu_assign_pointer(table->ufid_ti, new_ti);
964 call_rcu(&ti->rcu, flow_tbl_destroy_rcu_cb);
969 /* Must be called with OVS mutex held. */
970 int ovs_flow_tbl_insert(struct flow_table *table, struct sw_flow *flow,
971 const struct sw_flow_mask *mask)
975 err = flow_mask_insert(table, flow, mask);
978 flow_key_insert(table, flow);
979 if (ovs_identifier_is_ufid(&flow->id))
980 flow_ufid_insert(table, flow);
985 /* Initializes the flow module.
986 * Returns zero if successful or a negative error code.
988 int ovs_flow_init(void)
990 BUILD_BUG_ON(__alignof__(struct sw_flow_key) % __alignof__(long));
991 BUILD_BUG_ON(sizeof(struct sw_flow_key) % sizeof(long));
993 flow_cache = kmem_cache_create("sw_flow", sizeof(struct sw_flow)
995 * sizeof(struct flow_stats *)),
997 if (flow_cache == NULL)
1001 = kmem_cache_create("sw_flow_stats", sizeof(struct flow_stats),
1002 0, SLAB_HWCACHE_ALIGN, NULL);
1003 if (flow_stats_cache == NULL) {
1004 kmem_cache_destroy(flow_cache);
1012 /* Uninitializes the flow module. */
1013 void ovs_flow_exit(void)
1015 kmem_cache_destroy(flow_stats_cache);
1016 kmem_cache_destroy(flow_cache);