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authorPravin B Shelar <pshelar@nicira.com>2013-10-03 18:16:47 -0700
committerJesse Gross <jesse@nicira.com>2013-10-03 18:16:47 -0700
commite64457191a259537bbbfaebeba9a8043786af96f (patch)
tree579f47d3124b69a94b07878d65d27f71c4f7c9c5 /net/openvswitch/flow_table.c
parentf0627cfa24389cab25c67bb7ca902912216a8a2d (diff)
downloadlinux-e64457191a259537bbbfaebeba9a8043786af96f.tar.bz2
openvswitch: Restructure datapath.c and flow.c
Over the time datapath.c and flow.c has became pretty large files. Following patch restructures functionality of component into three different components: flow.c: contains flow extract. flow_netlink.c: netlink flow api. flow_table.c: flow table api. This patch restructures code without changing logic. Signed-off-by: Pravin B Shelar <pshelar@nicira.com> Signed-off-by: Jesse Gross <jesse@nicira.com>
Diffstat (limited to 'net/openvswitch/flow_table.c')
-rw-r--r--net/openvswitch/flow_table.c517
1 files changed, 517 insertions, 0 deletions
diff --git a/net/openvswitch/flow_table.c b/net/openvswitch/flow_table.c
new file mode 100644
index 000000000000..dcadb75bb173
--- /dev/null
+++ b/net/openvswitch/flow_table.c
@@ -0,0 +1,517 @@
+/*
+ * Copyright (c) 2007-2013 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 <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/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>
+
+static struct kmem_cache *flow_cache;
+
+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,
+ const struct sw_flow_mask *mask)
+{
+ const long *m = (long *)((u8 *)&mask->key + mask->range.start);
+ const long *s = (long *)((u8 *)src + mask->range.start);
+ long *d = (long *)((u8 *)dst + mask->range.start);
+ int i;
+
+ /* The memory outside of the 'mask->range' are not set since
+ * further operations on 'dst' only uses contents within
+ * 'mask->range'.
+ */
+ for (i = 0; i < range_n_bytes(&mask->range); i += sizeof(long))
+ *d++ = *s++ & *m++;
+}
+
+struct sw_flow *ovs_flow_alloc(void)
+{
+ struct sw_flow *flow;
+
+ flow = kmem_cache_alloc(flow_cache, GFP_KERNEL);
+ if (!flow)
+ return ERR_PTR(-ENOMEM);
+
+ spin_lock_init(&flow->lock);
+ flow->sf_acts = NULL;
+ flow->mask = NULL;
+
+ return flow;
+}
+
+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)
+{
+ kfree((struct sf_flow_acts __force *)flow->sf_acts);
+ 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;
+
+ ovs_sw_flow_mask_del_ref(flow->mask, deferred);
+
+ 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 __flow_tbl_destroy(struct flow_table *table)
+{
+ int i;
+
+ if (table->keep_flows)
+ goto skip_flows;
+
+ for (i = 0; i < table->n_buckets; i++) {
+ struct sw_flow *flow;
+ struct hlist_head *head = flex_array_get(table->buckets, i);
+ struct hlist_node *n;
+ int ver = table->node_ver;
+
+ hlist_for_each_entry_safe(flow, n, head, hash_node[ver]) {
+ hlist_del(&flow->hash_node[ver]);
+ ovs_flow_free(flow, false);
+ }
+ }
+
+ BUG_ON(!list_empty(table->mask_list));
+ kfree(table->mask_list);
+
+skip_flows:
+ free_buckets(table->buckets);
+ kfree(table);
+}
+
+static struct flow_table *__flow_tbl_alloc(int new_size)
+{
+ struct flow_table *table = kmalloc(sizeof(*table), GFP_KERNEL);
+
+ if (!table)
+ return NULL;
+
+ table->buckets = alloc_buckets(new_size);
+
+ if (!table->buckets) {
+ kfree(table);
+ return NULL;
+ }
+ table->n_buckets = new_size;
+ table->count = 0;
+ table->node_ver = 0;
+ table->keep_flows = false;
+ get_random_bytes(&table->hash_seed, sizeof(u32));
+ table->mask_list = NULL;
+
+ return table;
+}
+
+struct flow_table *ovs_flow_tbl_alloc(int new_size)
+{
+ struct flow_table *table = __flow_tbl_alloc(new_size);
+
+ if (!table)
+ return NULL;
+
+ table->mask_list = kmalloc(sizeof(struct list_head), GFP_KERNEL);
+ if (!table->mask_list) {
+ table->keep_flows = true;
+ __flow_tbl_destroy(table);
+ return NULL;
+ }
+ INIT_LIST_HEAD(table->mask_list);
+
+ return table;
+}
+
+static void flow_tbl_destroy_rcu_cb(struct rcu_head *rcu)
+{
+ struct flow_table *table = container_of(rcu, struct flow_table, rcu);
+
+ __flow_tbl_destroy(table);
+}
+
+void ovs_flow_tbl_destroy(struct flow_table *table, bool deferred)
+{
+ if (!table)
+ return;
+
+ if (deferred)
+ call_rcu(&table->rcu, flow_tbl_destroy_rcu_cb);
+ else
+ __flow_tbl_destroy(table);
+}
+
+struct sw_flow *ovs_flow_tbl_dump_next(struct flow_table *table,
+ u32 *bucket, u32 *last)
+{
+ struct sw_flow *flow;
+ struct hlist_head *head;
+ int ver;
+ int i;
+
+ ver = table->node_ver;
+ while (*bucket < table->n_buckets) {
+ i = 0;
+ head = flex_array_get(table->buckets, *bucket);
+ hlist_for_each_entry_rcu(flow, head, hash_node[ver]) {
+ if (i < *last) {
+ i++;
+ continue;
+ }
+ *last = i + 1;
+ return flow;
+ }
+ (*bucket)++;
+ *last = 0;
+ }
+
+ return NULL;
+}
+
+static struct hlist_head *find_bucket(struct flow_table *table, u32 hash)
+{
+ hash = jhash_1word(hash, table->hash_seed);
+ return flex_array_get(table->buckets,
+ (hash & (table->n_buckets - 1)));
+}
+
+static void __tbl_insert(struct flow_table *table, struct sw_flow *flow)
+{
+ struct hlist_head *head;
+
+ head = find_bucket(table, flow->hash);
+ hlist_add_head_rcu(&flow->hash_node[table->node_ver], head);
+
+ table->count++;
+}
+
+static void flow_table_copy_flows(struct flow_table *old,
+ struct flow_table *new)
+{
+ 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);
+
+ hlist_for_each_entry(flow, head, hash_node[old_ver])
+ __tbl_insert(new, flow);
+ }
+
+ new->mask_list = old->mask_list;
+ old->keep_flows = true;
+}
+
+static struct flow_table *__flow_tbl_rehash(struct flow_table *table,
+ int n_buckets)
+{
+ struct flow_table *new_table;
+
+ new_table = __flow_tbl_alloc(n_buckets);
+ if (!new_table)
+ return ERR_PTR(-ENOMEM);
+
+ flow_table_copy_flows(table, new_table);
+
+ return new_table;
+}
+
+struct flow_table *ovs_flow_tbl_rehash(struct flow_table *table)
+{
+ return __flow_tbl_rehash(table, table->n_buckets);
+}
+
+struct flow_table *ovs_flow_tbl_expand(struct flow_table *table)
+{
+ return __flow_tbl_rehash(table, table->n_buckets * 2);
+}
+
+static u32 flow_hash(const struct sw_flow_key *key, int key_start,
+ int key_end)
+{
+ u32 *hash_key = (u32 *)((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_key.ipv4_dst)
+ 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 = (long *)((u8 *)key1 + key_start);
+ const long *cp2 = (long *)((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,
+ int key_start, int key_end)
+{
+ return cmp_key(&flow->key, key, key_start, key_end);
+}
+
+bool ovs_flow_cmp_unmasked_key(const struct sw_flow *flow,
+ 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;
+
+ return cmp_key(&flow->unmasked_key, key, key_start, key_end);
+}
+
+static struct sw_flow *masked_flow_lookup(struct flow_table *table,
+ const struct sw_flow_key *unmasked,
+ struct sw_flow_mask *mask)
+{
+ struct sw_flow *flow;
+ struct hlist_head *head;
+ int key_start = mask->range.start;
+ int key_end = mask->range.end;
+ u32 hash;
+ struct sw_flow_key masked_key;
+
+ ovs_flow_mask_key(&masked_key, unmasked, mask);
+ hash = flow_hash(&masked_key, key_start, key_end);
+ head = find_bucket(table, hash);
+ hlist_for_each_entry_rcu(flow, head, hash_node[table->node_ver]) {
+ if (flow->mask == mask &&
+ flow_cmp_masked_key(flow, &masked_key,
+ key_start, key_end))
+ return flow;
+ }
+ return NULL;
+}
+
+struct sw_flow *ovs_flow_tbl_lookup(struct flow_table *tbl,
+ const struct sw_flow_key *key)
+{
+ struct sw_flow *flow = NULL;
+ struct sw_flow_mask *mask;
+
+ list_for_each_entry_rcu(mask, tbl->mask_list, list) {
+ flow = masked_flow_lookup(tbl, key, mask);
+ if (flow) /* Found */
+ break;
+ }
+
+ return flow;
+}
+
+void ovs_flow_tbl_insert(struct flow_table *table, struct sw_flow *flow)
+{
+ flow->hash = flow_hash(&flow->key, flow->mask->range.start,
+ flow->mask->range.end);
+ __tbl_insert(table, flow);
+}
+
+void ovs_flow_tbl_remove(struct flow_table *table, struct sw_flow *flow)
+{
+ BUG_ON(table->count == 0);
+ hlist_del_rcu(&flow->hash_node[table->node_ver]);
+ table->count--;
+}
+
+struct sw_flow_mask *ovs_sw_flow_mask_alloc(void)
+{
+ struct sw_flow_mask *mask;
+
+ mask = kmalloc(sizeof(*mask), GFP_KERNEL);
+ if (mask)
+ mask->ref_count = 0;
+
+ return mask;
+}
+
+void ovs_sw_flow_mask_add_ref(struct sw_flow_mask *mask)
+{
+ mask->ref_count++;
+}
+
+static void rcu_free_sw_flow_mask_cb(struct rcu_head *rcu)
+{
+ struct sw_flow_mask *mask = container_of(rcu, struct sw_flow_mask, rcu);
+
+ kfree(mask);
+}
+
+void ovs_sw_flow_mask_del_ref(struct sw_flow_mask *mask, bool deferred)
+{
+ if (!mask)
+ return;
+
+ BUG_ON(!mask->ref_count);
+ mask->ref_count--;
+
+ if (!mask->ref_count) {
+ list_del_rcu(&mask->list);
+ if (deferred)
+ call_rcu(&mask->rcu, rcu_free_sw_flow_mask_cb);
+ else
+ kfree(mask);
+ }
+}
+
+static bool mask_equal(const struct sw_flow_mask *a,
+ const struct sw_flow_mask *b)
+{
+ u8 *a_ = (u8 *)&a->key + a->range.start;
+ u8 *b_ = (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);
+}
+
+struct sw_flow_mask *ovs_sw_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 a new mask into the mask list.
+ * The caller needs to make sure that 'mask' is not the same
+ * as any masks that are already on the list.
+ */
+void ovs_sw_flow_mask_insert(struct flow_table *tbl, struct sw_flow_mask *mask)
+{
+ list_add_rcu(&mask->list, tbl->mask_list);
+}
+
+/* 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), 0,
+ 0, NULL);
+ if (flow_cache == NULL)
+ return -ENOMEM;
+
+ return 0;
+}
+
+/* Uninitializes the flow module. */
+void ovs_flow_exit(void)
+{
+ kmem_cache_destroy(flow_cache);
+}