v4.19.13 snapshot.
diff --git a/net/openvswitch/flow_table.c b/net/openvswitch/flow_table.c
new file mode 100644
index 0000000..80ea2a7
--- /dev/null
+++ b/net/openvswitch/flow_table.c
@@ -0,0 +1,777 @@
+/*
+ * Copyright (c) 2007-2014 Nicira, Inc.
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of version 2 of the GNU General Public
+ * License as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ * General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
+ * 02110-1301, USA
+ */
+
+#include "flow.h"
+#include "datapath.h"
+#include "flow_netlink.h"
+#include <linux/uaccess.h>
+#include <linux/netdevice.h>
+#include <linux/etherdevice.h>
+#include <linux/if_ether.h>
+#include <linux/if_vlan.h>
+#include <net/llc_pdu.h>
+#include <linux/kernel.h>
+#include <linux/jhash.h>
+#include <linux/jiffies.h>
+#include <linux/llc.h>
+#include <linux/module.h>
+#include <linux/in.h>
+#include <linux/rcupdate.h>
+#include <linux/cpumask.h>
+#include <linux/if_arp.h>
+#include <linux/ip.h>
+#include <linux/ipv6.h>
+#include <linux/sctp.h>
+#include <linux/tcp.h>
+#include <linux/udp.h>
+#include <linux/icmp.h>
+#include <linux/icmpv6.h>
+#include <linux/rculist.h>
+#include <net/ip.h>
+#include <net/ipv6.h>
+#include <net/ndisc.h>
+
+#define TBL_MIN_BUCKETS 1024
+#define REHASH_INTERVAL (10 * 60 * HZ)
+
+static struct kmem_cache *flow_cache;
+struct kmem_cache *flow_stats_cache __read_mostly;
+
+static u16 range_n_bytes(const struct sw_flow_key_range *range)
+{
+ return range->end - range->start;
+}
+
+void ovs_flow_mask_key(struct sw_flow_key *dst, const struct sw_flow_key *src,
+ bool full, const struct sw_flow_mask *mask)
+{
+ int start = full ? 0 : mask->range.start;
+ int len = full ? sizeof *dst : range_n_bytes(&mask->range);
+ const long *m = (const long *)((const u8 *)&mask->key + start);
+ const long *s = (const long *)((const u8 *)src + start);
+ long *d = (long *)((u8 *)dst + start);
+ int i;
+
+ /* If 'full' is true then all of 'dst' is fully initialized. Otherwise,
+ * if 'full' is false the memory outside of the 'mask->range' is left
+ * uninitialized. This can be used as an optimization when further
+ * operations on 'dst' only use contents within 'mask->range'.
+ */
+ for (i = 0; i < len; i += sizeof(long))
+ *d++ = *s++ & *m++;
+}
+
+struct sw_flow *ovs_flow_alloc(void)
+{
+ struct sw_flow *flow;
+ struct flow_stats *stats;
+
+ flow = kmem_cache_zalloc(flow_cache, GFP_KERNEL);
+ if (!flow)
+ return ERR_PTR(-ENOMEM);
+
+ flow->stats_last_writer = -1;
+
+ /* Initialize the default stat node. */
+ stats = kmem_cache_alloc_node(flow_stats_cache,
+ GFP_KERNEL | __GFP_ZERO,
+ node_online(0) ? 0 : NUMA_NO_NODE);
+ if (!stats)
+ goto err;
+
+ spin_lock_init(&stats->lock);
+
+ RCU_INIT_POINTER(flow->stats[0], stats);
+
+ cpumask_set_cpu(0, &flow->cpu_used_mask);
+
+ return flow;
+err:
+ kmem_cache_free(flow_cache, flow);
+ return ERR_PTR(-ENOMEM);
+}
+
+int ovs_flow_tbl_count(const struct flow_table *table)
+{
+ return table->count;
+}
+
+static struct flex_array *alloc_buckets(unsigned int n_buckets)
+{
+ struct flex_array *buckets;
+ int i, err;
+
+ buckets = flex_array_alloc(sizeof(struct hlist_head),
+ n_buckets, GFP_KERNEL);
+ if (!buckets)
+ return NULL;
+
+ err = flex_array_prealloc(buckets, 0, n_buckets, GFP_KERNEL);
+ if (err) {
+ flex_array_free(buckets);
+ return NULL;
+ }
+
+ for (i = 0; i < n_buckets; i++)
+ INIT_HLIST_HEAD((struct hlist_head *)
+ flex_array_get(buckets, i));
+
+ return buckets;
+}
+
+static void flow_free(struct sw_flow *flow)
+{
+ int cpu;
+
+ if (ovs_identifier_is_key(&flow->id))
+ kfree(flow->id.unmasked_key);
+ if (flow->sf_acts)
+ ovs_nla_free_flow_actions((struct sw_flow_actions __force *)flow->sf_acts);
+ /* We open code this to make sure cpu 0 is always considered */
+ for (cpu = 0; cpu < nr_cpu_ids; cpu = cpumask_next(cpu, &flow->cpu_used_mask))
+ if (flow->stats[cpu])
+ kmem_cache_free(flow_stats_cache,
+ (struct flow_stats __force *)flow->stats[cpu]);
+ kmem_cache_free(flow_cache, flow);
+}
+
+static void rcu_free_flow_callback(struct rcu_head *rcu)
+{
+ struct sw_flow *flow = container_of(rcu, struct sw_flow, rcu);
+
+ flow_free(flow);
+}
+
+void ovs_flow_free(struct sw_flow *flow, bool deferred)
+{
+ if (!flow)
+ return;
+
+ if (deferred)
+ call_rcu(&flow->rcu, rcu_free_flow_callback);
+ else
+ flow_free(flow);
+}
+
+static void free_buckets(struct flex_array *buckets)
+{
+ flex_array_free(buckets);
+}
+
+
+static void __table_instance_destroy(struct table_instance *ti)
+{
+ free_buckets(ti->buckets);
+ kfree(ti);
+}
+
+static struct table_instance *table_instance_alloc(int new_size)
+{
+ struct table_instance *ti = kmalloc(sizeof(*ti), GFP_KERNEL);
+
+ if (!ti)
+ return NULL;
+
+ ti->buckets = alloc_buckets(new_size);
+
+ if (!ti->buckets) {
+ kfree(ti);
+ return NULL;
+ }
+ ti->n_buckets = new_size;
+ ti->node_ver = 0;
+ ti->keep_flows = false;
+ get_random_bytes(&ti->hash_seed, sizeof(u32));
+
+ return ti;
+}
+
+int ovs_flow_tbl_init(struct flow_table *table)
+{
+ struct table_instance *ti, *ufid_ti;
+
+ ti = table_instance_alloc(TBL_MIN_BUCKETS);
+
+ if (!ti)
+ return -ENOMEM;
+
+ ufid_ti = table_instance_alloc(TBL_MIN_BUCKETS);
+ if (!ufid_ti)
+ goto free_ti;
+
+ rcu_assign_pointer(table->ti, ti);
+ rcu_assign_pointer(table->ufid_ti, ufid_ti);
+ INIT_LIST_HEAD(&table->mask_list);
+ table->last_rehash = jiffies;
+ table->count = 0;
+ table->ufid_count = 0;
+ return 0;
+
+free_ti:
+ __table_instance_destroy(ti);
+ return -ENOMEM;
+}
+
+static void flow_tbl_destroy_rcu_cb(struct rcu_head *rcu)
+{
+ struct table_instance *ti = container_of(rcu, struct table_instance, rcu);
+
+ __table_instance_destroy(ti);
+}
+
+static void table_instance_destroy(struct table_instance *ti,
+ struct table_instance *ufid_ti,
+ bool deferred)
+{
+ int i;
+
+ if (!ti)
+ return;
+
+ BUG_ON(!ufid_ti);
+ if (ti->keep_flows)
+ goto skip_flows;
+
+ for (i = 0; i < ti->n_buckets; i++) {
+ struct sw_flow *flow;
+ struct hlist_head *head = flex_array_get(ti->buckets, i);
+ struct hlist_node *n;
+ int ver = ti->node_ver;
+ int ufid_ver = ufid_ti->node_ver;
+
+ hlist_for_each_entry_safe(flow, n, head, flow_table.node[ver]) {
+ hlist_del_rcu(&flow->flow_table.node[ver]);
+ if (ovs_identifier_is_ufid(&flow->id))
+ hlist_del_rcu(&flow->ufid_table.node[ufid_ver]);
+ ovs_flow_free(flow, deferred);
+ }
+ }
+
+skip_flows:
+ if (deferred) {
+ call_rcu(&ti->rcu, flow_tbl_destroy_rcu_cb);
+ call_rcu(&ufid_ti->rcu, flow_tbl_destroy_rcu_cb);
+ } else {
+ __table_instance_destroy(ti);
+ __table_instance_destroy(ufid_ti);
+ }
+}
+
+/* No need for locking this function is called from RCU callback or
+ * error path.
+ */
+void ovs_flow_tbl_destroy(struct flow_table *table)
+{
+ struct table_instance *ti = rcu_dereference_raw(table->ti);
+ struct table_instance *ufid_ti = rcu_dereference_raw(table->ufid_ti);
+
+ table_instance_destroy(ti, ufid_ti, false);
+}
+
+struct sw_flow *ovs_flow_tbl_dump_next(struct table_instance *ti,
+ u32 *bucket, u32 *last)
+{
+ struct sw_flow *flow;
+ struct hlist_head *head;
+ int ver;
+ int i;
+
+ ver = ti->node_ver;
+ while (*bucket < ti->n_buckets) {
+ i = 0;
+ head = flex_array_get(ti->buckets, *bucket);
+ hlist_for_each_entry_rcu(flow, head, flow_table.node[ver]) {
+ if (i < *last) {
+ i++;
+ continue;
+ }
+ *last = i + 1;
+ return flow;
+ }
+ (*bucket)++;
+ *last = 0;
+ }
+
+ return NULL;
+}
+
+static struct hlist_head *find_bucket(struct table_instance *ti, u32 hash)
+{
+ hash = jhash_1word(hash, ti->hash_seed);
+ return flex_array_get(ti->buckets,
+ (hash & (ti->n_buckets - 1)));
+}
+
+static void table_instance_insert(struct table_instance *ti,
+ struct sw_flow *flow)
+{
+ struct hlist_head *head;
+
+ head = find_bucket(ti, flow->flow_table.hash);
+ hlist_add_head_rcu(&flow->flow_table.node[ti->node_ver], head);
+}
+
+static void ufid_table_instance_insert(struct table_instance *ti,
+ struct sw_flow *flow)
+{
+ struct hlist_head *head;
+
+ head = find_bucket(ti, flow->ufid_table.hash);
+ hlist_add_head_rcu(&flow->ufid_table.node[ti->node_ver], head);
+}
+
+static void flow_table_copy_flows(struct table_instance *old,
+ struct table_instance *new, bool ufid)
+{
+ int old_ver;
+ int i;
+
+ old_ver = old->node_ver;
+ new->node_ver = !old_ver;
+
+ /* Insert in new table. */
+ for (i = 0; i < old->n_buckets; i++) {
+ struct sw_flow *flow;
+ struct hlist_head *head;
+
+ head = flex_array_get(old->buckets, i);
+
+ if (ufid)
+ hlist_for_each_entry(flow, head,
+ ufid_table.node[old_ver])
+ ufid_table_instance_insert(new, flow);
+ else
+ hlist_for_each_entry(flow, head,
+ flow_table.node[old_ver])
+ table_instance_insert(new, flow);
+ }
+
+ old->keep_flows = true;
+}
+
+static struct table_instance *table_instance_rehash(struct table_instance *ti,
+ int n_buckets, bool ufid)
+{
+ struct table_instance *new_ti;
+
+ new_ti = table_instance_alloc(n_buckets);
+ if (!new_ti)
+ return NULL;
+
+ flow_table_copy_flows(ti, new_ti, ufid);
+
+ return new_ti;
+}
+
+int ovs_flow_tbl_flush(struct flow_table *flow_table)
+{
+ struct table_instance *old_ti, *new_ti;
+ struct table_instance *old_ufid_ti, *new_ufid_ti;
+
+ new_ti = table_instance_alloc(TBL_MIN_BUCKETS);
+ if (!new_ti)
+ return -ENOMEM;
+ new_ufid_ti = table_instance_alloc(TBL_MIN_BUCKETS);
+ if (!new_ufid_ti)
+ goto err_free_ti;
+
+ old_ti = ovsl_dereference(flow_table->ti);
+ old_ufid_ti = ovsl_dereference(flow_table->ufid_ti);
+
+ rcu_assign_pointer(flow_table->ti, new_ti);
+ rcu_assign_pointer(flow_table->ufid_ti, new_ufid_ti);
+ flow_table->last_rehash = jiffies;
+ flow_table->count = 0;
+ flow_table->ufid_count = 0;
+
+ table_instance_destroy(old_ti, old_ufid_ti, true);
+ return 0;
+
+err_free_ti:
+ __table_instance_destroy(new_ti);
+ return -ENOMEM;
+}
+
+static u32 flow_hash(const struct sw_flow_key *key,
+ const struct sw_flow_key_range *range)
+{
+ int key_start = range->start;
+ int key_end = range->end;
+ const u32 *hash_key = (const u32 *)((const u8 *)key + key_start);
+ int hash_u32s = (key_end - key_start) >> 2;
+
+ /* Make sure number of hash bytes are multiple of u32. */
+ BUILD_BUG_ON(sizeof(long) % sizeof(u32));
+
+ return jhash2(hash_key, hash_u32s, 0);
+}
+
+static int flow_key_start(const struct sw_flow_key *key)
+{
+ if (key->tun_proto)
+ return 0;
+ else
+ return rounddown(offsetof(struct sw_flow_key, phy),
+ sizeof(long));
+}
+
+static bool cmp_key(const struct sw_flow_key *key1,
+ const struct sw_flow_key *key2,
+ int key_start, int key_end)
+{
+ const long *cp1 = (const long *)((const u8 *)key1 + key_start);
+ const long *cp2 = (const long *)((const u8 *)key2 + key_start);
+ long diffs = 0;
+ int i;
+
+ for (i = key_start; i < key_end; i += sizeof(long))
+ diffs |= *cp1++ ^ *cp2++;
+
+ return diffs == 0;
+}
+
+static bool flow_cmp_masked_key(const struct sw_flow *flow,
+ const struct sw_flow_key *key,
+ const struct sw_flow_key_range *range)
+{
+ return cmp_key(&flow->key, key, range->start, range->end);
+}
+
+static bool ovs_flow_cmp_unmasked_key(const struct sw_flow *flow,
+ const struct sw_flow_match *match)
+{
+ struct sw_flow_key *key = match->key;
+ int key_start = flow_key_start(key);
+ int key_end = match->range.end;
+
+ BUG_ON(ovs_identifier_is_ufid(&flow->id));
+ return cmp_key(flow->id.unmasked_key, key, key_start, key_end);
+}
+
+static struct sw_flow *masked_flow_lookup(struct table_instance *ti,
+ const struct sw_flow_key *unmasked,
+ const struct sw_flow_mask *mask)
+{
+ struct sw_flow *flow;
+ struct hlist_head *head;
+ u32 hash;
+ struct sw_flow_key masked_key;
+
+ ovs_flow_mask_key(&masked_key, unmasked, false, mask);
+ hash = flow_hash(&masked_key, &mask->range);
+ head = find_bucket(ti, hash);
+ hlist_for_each_entry_rcu(flow, head, flow_table.node[ti->node_ver]) {
+ if (flow->mask == mask && flow->flow_table.hash == hash &&
+ flow_cmp_masked_key(flow, &masked_key, &mask->range))
+ return flow;
+ }
+ return NULL;
+}
+
+struct sw_flow *ovs_flow_tbl_lookup_stats(struct flow_table *tbl,
+ const struct sw_flow_key *key,
+ u32 *n_mask_hit)
+{
+ struct table_instance *ti = rcu_dereference_ovsl(tbl->ti);
+ struct sw_flow_mask *mask;
+ struct sw_flow *flow;
+
+ *n_mask_hit = 0;
+ list_for_each_entry_rcu(mask, &tbl->mask_list, list) {
+ (*n_mask_hit)++;
+ flow = masked_flow_lookup(ti, key, mask);
+ if (flow) /* Found */
+ return flow;
+ }
+ return NULL;
+}
+
+struct sw_flow *ovs_flow_tbl_lookup(struct flow_table *tbl,
+ const struct sw_flow_key *key)
+{
+ u32 __always_unused n_mask_hit;
+
+ return ovs_flow_tbl_lookup_stats(tbl, key, &n_mask_hit);
+}
+
+struct sw_flow *ovs_flow_tbl_lookup_exact(struct flow_table *tbl,
+ const struct sw_flow_match *match)
+{
+ struct table_instance *ti = rcu_dereference_ovsl(tbl->ti);
+ struct sw_flow_mask *mask;
+ struct sw_flow *flow;
+
+ /* Always called under ovs-mutex. */
+ list_for_each_entry(mask, &tbl->mask_list, list) {
+ flow = masked_flow_lookup(ti, match->key, mask);
+ if (flow && ovs_identifier_is_key(&flow->id) &&
+ ovs_flow_cmp_unmasked_key(flow, match))
+ return flow;
+ }
+ return NULL;
+}
+
+static u32 ufid_hash(const struct sw_flow_id *sfid)
+{
+ return jhash(sfid->ufid, sfid->ufid_len, 0);
+}
+
+static bool ovs_flow_cmp_ufid(const struct sw_flow *flow,
+ const struct sw_flow_id *sfid)
+{
+ if (flow->id.ufid_len != sfid->ufid_len)
+ return false;
+
+ return !memcmp(flow->id.ufid, sfid->ufid, sfid->ufid_len);
+}
+
+bool ovs_flow_cmp(const struct sw_flow *flow, const struct sw_flow_match *match)
+{
+ if (ovs_identifier_is_ufid(&flow->id))
+ return flow_cmp_masked_key(flow, match->key, &match->range);
+
+ return ovs_flow_cmp_unmasked_key(flow, match);
+}
+
+struct sw_flow *ovs_flow_tbl_lookup_ufid(struct flow_table *tbl,
+ const struct sw_flow_id *ufid)
+{
+ struct table_instance *ti = rcu_dereference_ovsl(tbl->ufid_ti);
+ struct sw_flow *flow;
+ struct hlist_head *head;
+ u32 hash;
+
+ hash = ufid_hash(ufid);
+ head = find_bucket(ti, hash);
+ hlist_for_each_entry_rcu(flow, head, ufid_table.node[ti->node_ver]) {
+ if (flow->ufid_table.hash == hash &&
+ ovs_flow_cmp_ufid(flow, ufid))
+ return flow;
+ }
+ return NULL;
+}
+
+int ovs_flow_tbl_num_masks(const struct flow_table *table)
+{
+ struct sw_flow_mask *mask;
+ int num = 0;
+
+ list_for_each_entry(mask, &table->mask_list, list)
+ num++;
+
+ return num;
+}
+
+static struct table_instance *table_instance_expand(struct table_instance *ti,
+ bool ufid)
+{
+ return table_instance_rehash(ti, ti->n_buckets * 2, ufid);
+}
+
+/* Remove 'mask' from the mask list, if it is not needed any more. */
+static void flow_mask_remove(struct flow_table *tbl, struct sw_flow_mask *mask)
+{
+ if (mask) {
+ /* ovs-lock is required to protect mask-refcount and
+ * mask list.
+ */
+ ASSERT_OVSL();
+ BUG_ON(!mask->ref_count);
+ mask->ref_count--;
+
+ if (!mask->ref_count) {
+ list_del_rcu(&mask->list);
+ kfree_rcu(mask, rcu);
+ }
+ }
+}
+
+/* Must be called with OVS mutex held. */
+void ovs_flow_tbl_remove(struct flow_table *table, struct sw_flow *flow)
+{
+ struct table_instance *ti = ovsl_dereference(table->ti);
+ struct table_instance *ufid_ti = ovsl_dereference(table->ufid_ti);
+
+ BUG_ON(table->count == 0);
+ hlist_del_rcu(&flow->flow_table.node[ti->node_ver]);
+ table->count--;
+ if (ovs_identifier_is_ufid(&flow->id)) {
+ hlist_del_rcu(&flow->ufid_table.node[ufid_ti->node_ver]);
+ table->ufid_count--;
+ }
+
+ /* RCU delete the mask. 'flow->mask' is not NULLed, as it should be
+ * accessible as long as the RCU read lock is held.
+ */
+ flow_mask_remove(table, flow->mask);
+}
+
+static struct sw_flow_mask *mask_alloc(void)
+{
+ struct sw_flow_mask *mask;
+
+ mask = kmalloc(sizeof(*mask), GFP_KERNEL);
+ if (mask)
+ mask->ref_count = 1;
+
+ return mask;
+}
+
+static bool mask_equal(const struct sw_flow_mask *a,
+ const struct sw_flow_mask *b)
+{
+ const u8 *a_ = (const u8 *)&a->key + a->range.start;
+ const u8 *b_ = (const u8 *)&b->key + b->range.start;
+
+ return (a->range.end == b->range.end)
+ && (a->range.start == b->range.start)
+ && (memcmp(a_, b_, range_n_bytes(&a->range)) == 0);
+}
+
+static struct sw_flow_mask *flow_mask_find(const struct flow_table *tbl,
+ const struct sw_flow_mask *mask)
+{
+ struct list_head *ml;
+
+ list_for_each(ml, &tbl->mask_list) {
+ struct sw_flow_mask *m;
+ m = container_of(ml, struct sw_flow_mask, list);
+ if (mask_equal(mask, m))
+ return m;
+ }
+
+ return NULL;
+}
+
+/* Add 'mask' into the mask list, if it is not already there. */
+static int flow_mask_insert(struct flow_table *tbl, struct sw_flow *flow,
+ const struct sw_flow_mask *new)
+{
+ struct sw_flow_mask *mask;
+ mask = flow_mask_find(tbl, new);
+ if (!mask) {
+ /* Allocate a new mask if none exsits. */
+ mask = mask_alloc();
+ if (!mask)
+ return -ENOMEM;
+ mask->key = new->key;
+ mask->range = new->range;
+ list_add_rcu(&mask->list, &tbl->mask_list);
+ } else {
+ BUG_ON(!mask->ref_count);
+ mask->ref_count++;
+ }
+
+ flow->mask = mask;
+ return 0;
+}
+
+/* Must be called with OVS mutex held. */
+static void flow_key_insert(struct flow_table *table, struct sw_flow *flow)
+{
+ struct table_instance *new_ti = NULL;
+ struct table_instance *ti;
+
+ flow->flow_table.hash = flow_hash(&flow->key, &flow->mask->range);
+ ti = ovsl_dereference(table->ti);
+ table_instance_insert(ti, flow);
+ table->count++;
+
+ /* Expand table, if necessary, to make room. */
+ if (table->count > ti->n_buckets)
+ new_ti = table_instance_expand(ti, false);
+ else if (time_after(jiffies, table->last_rehash + REHASH_INTERVAL))
+ new_ti = table_instance_rehash(ti, ti->n_buckets, false);
+
+ if (new_ti) {
+ rcu_assign_pointer(table->ti, new_ti);
+ call_rcu(&ti->rcu, flow_tbl_destroy_rcu_cb);
+ table->last_rehash = jiffies;
+ }
+}
+
+/* Must be called with OVS mutex held. */
+static void flow_ufid_insert(struct flow_table *table, struct sw_flow *flow)
+{
+ struct table_instance *ti;
+
+ flow->ufid_table.hash = ufid_hash(&flow->id);
+ ti = ovsl_dereference(table->ufid_ti);
+ ufid_table_instance_insert(ti, flow);
+ table->ufid_count++;
+
+ /* Expand table, if necessary, to make room. */
+ if (table->ufid_count > ti->n_buckets) {
+ struct table_instance *new_ti;
+
+ new_ti = table_instance_expand(ti, true);
+ if (new_ti) {
+ rcu_assign_pointer(table->ufid_ti, new_ti);
+ call_rcu(&ti->rcu, flow_tbl_destroy_rcu_cb);
+ }
+ }
+}
+
+/* Must be called with OVS mutex held. */
+int ovs_flow_tbl_insert(struct flow_table *table, struct sw_flow *flow,
+ const struct sw_flow_mask *mask)
+{
+ int err;
+
+ err = flow_mask_insert(table, flow, mask);
+ if (err)
+ return err;
+ flow_key_insert(table, flow);
+ if (ovs_identifier_is_ufid(&flow->id))
+ flow_ufid_insert(table, flow);
+
+ return 0;
+}
+
+/* Initializes the flow module.
+ * Returns zero if successful or a negative error code. */
+int ovs_flow_init(void)
+{
+ BUILD_BUG_ON(__alignof__(struct sw_flow_key) % __alignof__(long));
+ BUILD_BUG_ON(sizeof(struct sw_flow_key) % sizeof(long));
+
+ flow_cache = kmem_cache_create("sw_flow", sizeof(struct sw_flow)
+ + (nr_cpu_ids
+ * sizeof(struct flow_stats *)),
+ 0, 0, NULL);
+ if (flow_cache == NULL)
+ return -ENOMEM;
+
+ flow_stats_cache
+ = kmem_cache_create("sw_flow_stats", sizeof(struct flow_stats),
+ 0, SLAB_HWCACHE_ALIGN, NULL);
+ if (flow_stats_cache == NULL) {
+ kmem_cache_destroy(flow_cache);
+ flow_cache = NULL;
+ return -ENOMEM;
+ }
+
+ return 0;
+}
+
+/* Uninitializes the flow module. */
+void ovs_flow_exit(void)
+{
+ kmem_cache_destroy(flow_stats_cache);
+ kmem_cache_destroy(flow_cache);
+}