2 * Copyright (c) 2008, 2009, 2010, 2011, 2012, 2013 Nicira, Inc.
4 * Licensed under the Apache License, Version 2.0 (the "License");
5 * you may not use this file except in compliance with the License.
6 * You may obtain a copy of the License at:
8 * http://www.apache.org/licenses/LICENSE-2.0
10 * Unless required by applicable law or agreed to in writing, software
11 * distributed under the License is distributed on an "AS IS" BASIS,
12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13 * See the License for the specific language governing permissions and
14 * limitations under the License.
17 #ifndef MAC_LEARNING_H
18 #define MAC_LEARNING_H 1
23 #include "ovs-atomic.h"
24 #include "ovs-thread.h"
30 /* Default maximum size of a MAC learning table, in entries. */
31 #define MAC_DEFAULT_MAX 2048
33 /* Time, in seconds, before expiring a mac_entry due to inactivity. */
34 #define MAC_ENTRY_DEFAULT_IDLE_TIME 300
36 /* Time, in seconds, to lock an entry updated by a gratuitous ARP to avoid
37 * relearning based on a reflection from a bond slave. */
38 #define MAC_GRAT_ARP_LOCK_TIME 5
40 /* A MAC learning table entry.
41 * Guarded by owning 'mac_learning''s rwlock */
43 struct hmap_node hmap_node; /* Node in a mac_learning hmap. */
44 time_t expires; /* Expiration time. */
45 time_t grat_arp_lock; /* Gratuitous ARP lock expiration time. */
46 uint8_t mac[ETH_ADDR_LEN]; /* Known MAC address. */
47 uint16_t vlan; /* VLAN tag. */
49 /* The following are marked guarded to prevent users from iterating over or
50 * accessing a mac_entry without hodling the parent mac_learning rwlock. */
51 struct list lru_node OVS_GUARDED; /* Element in 'lrus' list. */
60 /* Sets a gratuitous ARP lock on 'mac' that will expire in
61 * MAC_GRAT_ARP_LOCK_TIME seconds. */
62 static inline void mac_entry_set_grat_arp_lock(struct mac_entry *mac)
64 mac->grat_arp_lock = time_now() + MAC_GRAT_ARP_LOCK_TIME;
67 /* Returns true if a gratuitous ARP lock is in effect on 'mac', false if none
68 * has ever been asserted or if it has expired. */
69 static inline bool mac_entry_is_grat_arp_locked(const struct mac_entry *mac)
71 return time_now() < mac->grat_arp_lock;
74 /* MAC learning table. */
76 struct hmap table; /* Learning table. */
77 struct list lrus OVS_GUARDED; /* In-use entries, least recently used at the
78 front, most recently used at the back. */
79 uint32_t secret; /* Secret for randomizing hash table. */
80 unsigned long *flood_vlans; /* Bitmap of learning disabled VLANs. */
81 unsigned int idle_time; /* Max age before deleting an entry. */
82 size_t max_entries; /* Max number of learned MACs. */
83 struct ovs_refcount ref_cnt;
84 struct ovs_rwlock rwlock;
88 int mac_entry_age(const struct mac_learning *ml, const struct mac_entry *e)
89 OVS_REQ_RDLOCK(ml->rwlock);
92 struct mac_learning *mac_learning_create(unsigned int idle_time);
93 struct mac_learning *mac_learning_ref(const struct mac_learning *);
94 void mac_learning_unref(struct mac_learning *);
96 bool mac_learning_run(struct mac_learning *ml) OVS_REQ_WRLOCK(ml->rwlock);
97 void mac_learning_wait(struct mac_learning *ml)
98 OVS_REQ_RDLOCK(ml->rwlock);
101 bool mac_learning_set_flood_vlans(struct mac_learning *ml,
102 const unsigned long *bitmap)
103 OVS_REQ_WRLOCK(ml->rwlock);
104 void mac_learning_set_idle_time(struct mac_learning *ml,
105 unsigned int idle_time)
106 OVS_REQ_WRLOCK(ml->rwlock);
107 void mac_learning_set_max_entries(struct mac_learning *ml, size_t max_entries)
108 OVS_REQ_WRLOCK(ml->rwlock);
111 bool mac_learning_may_learn(const struct mac_learning *ml,
112 const uint8_t src_mac[ETH_ADDR_LEN],
114 OVS_REQ_RDLOCK(ml->rwlock);
115 struct mac_entry *mac_learning_insert(struct mac_learning *ml,
116 const uint8_t src[ETH_ADDR_LEN],
118 OVS_REQ_WRLOCK(ml->rwlock);
119 void mac_learning_changed(struct mac_learning *ml) OVS_REQ_WRLOCK(ml->rwlock);
122 struct mac_entry *mac_learning_lookup(const struct mac_learning *ml,
123 const uint8_t dst[ETH_ADDR_LEN],
125 OVS_REQ_RDLOCK(ml->rwlock);
128 void mac_learning_expire(struct mac_learning *ml, struct mac_entry *e)
129 OVS_REQ_WRLOCK(ml->rwlock);
130 void mac_learning_flush(struct mac_learning *ml) OVS_REQ_WRLOCK(ml->rwlock);
132 #endif /* mac-learning.h */