1 /* Copyright (C) 2007-2013 B.A.T.M.A.N. contributors: 2 * 3 * Marek Lindner, Simon Wunderlich 4 * 5 * This program is free software; you can redistribute it and/or 6 * modify it under the terms of version 2 of the GNU General Public 7 * License as published by the Free Software Foundation. 8 * 9 * This program is distributed in the hope that it will be useful, but 10 * WITHOUT ANY WARRANTY; without even the implied warranty of 11 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU 12 * General Public License for more details. 13 * 14 * You should have received a copy of the GNU General Public License 15 * along with this program; if not, write to the Free Software 16 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 17 * 02110-1301, USA 18 */ 19 20 #ifndef _NET_BATMAN_ADV_ORIGINATOR_H_ 21 #define _NET_BATMAN_ADV_ORIGINATOR_H_ 22 23 #include "hash.h" 24 25 int batadv_originator_init(struct batadv_priv *bat_priv); 26 void batadv_originator_free(struct batadv_priv *bat_priv); 27 void batadv_purge_orig_ref(struct batadv_priv *bat_priv); 28 void batadv_orig_node_free_ref(struct batadv_orig_node *orig_node); 29 void batadv_orig_node_free_ref_now(struct batadv_orig_node *orig_node); 30 struct batadv_orig_node *batadv_get_orig_node(struct batadv_priv *bat_priv, 31 const uint8_t *addr); 32 struct batadv_neigh_node * 33 batadv_neigh_node_new(struct batadv_hard_iface *hard_iface, 34 const uint8_t *neigh_addr, uint32_t seqno); 35 void batadv_neigh_node_free_ref(struct batadv_neigh_node *neigh_node); 36 struct batadv_neigh_node * 37 batadv_orig_node_get_router(struct batadv_orig_node *orig_node); 38 int batadv_orig_seq_print_text(struct seq_file *seq, void *offset); 39 int batadv_orig_hash_add_if(struct batadv_hard_iface *hard_iface, 40 int max_if_num); 41 int batadv_orig_hash_del_if(struct batadv_hard_iface *hard_iface, 42 int max_if_num); 43 44 45 /* hashfunction to choose an entry in a hash table of given size 46 * hash algorithm from http://en.wikipedia.org/wiki/Hash_table 47 */ 48 static inline uint32_t batadv_choose_orig(const void *data, uint32_t size) 49 { 50 const unsigned char *key = data; 51 uint32_t hash = 0; 52 size_t i; 53 54 for (i = 0; i < 6; i++) { 55 hash += key[i]; 56 hash += (hash << 10); 57 hash ^= (hash >> 6); 58 } 59 60 hash += (hash << 3); 61 hash ^= (hash >> 11); 62 hash += (hash << 15); 63 64 return hash % size; 65 } 66 67 static inline struct batadv_orig_node * 68 batadv_orig_hash_find(struct batadv_priv *bat_priv, const void *data) 69 { 70 struct batadv_hashtable *hash = bat_priv->orig_hash; 71 struct hlist_head *head; 72 struct batadv_orig_node *orig_node, *orig_node_tmp = NULL; 73 int index; 74 75 if (!hash) 76 return NULL; 77 78 index = batadv_choose_orig(data, hash->size); 79 head = &hash->table[index]; 80 81 rcu_read_lock(); 82 hlist_for_each_entry_rcu(orig_node, head, hash_entry) { 83 if (!batadv_compare_eth(orig_node, data)) 84 continue; 85 86 if (!atomic_inc_not_zero(&orig_node->refcount)) 87 continue; 88 89 orig_node_tmp = orig_node; 90 break; 91 } 92 rcu_read_unlock(); 93 94 return orig_node_tmp; 95 } 96 97 #endif /* _NET_BATMAN_ADV_ORIGINATOR_H_ */ 98