/* Copyright (C) 2006-2017 B.A.T.M.A.N. contributors: * * Simon Wunderlich, Marek Lindner * * 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, see . */ #ifndef _NET_BATMAN_ADV_HASH_H_ #define _NET_BATMAN_ADV_HASH_H_ #include "main.h" #include #include #include #include #include #include struct lock_class_key; /* callback to a compare function. should compare 2 element datas for their * keys * * Return: true if same and false if not same */ typedef bool (*batadv_hashdata_compare_cb)(const struct hlist_node *, const void *); /* the hashfunction * * Return: an index based on the key in the data of the first argument and the * size the second */ typedef u32 (*batadv_hashdata_choose_cb)(const void *, u32); typedef void (*batadv_hashdata_free_cb)(struct hlist_node *, void *); struct batadv_hashtable { struct hlist_head *table; /* the hashtable itself with the buckets */ spinlock_t *list_locks; /* spinlock for each hash list entry */ u32 size; /* size of hashtable */ }; /* allocates and clears the hash */ struct batadv_hashtable *batadv_hash_new(u32 size); /* set class key for all locks */ void batadv_hash_set_lock_class(struct batadv_hashtable *hash, struct lock_class_key *key); /* free only the hashtable and the hash itself. */ void batadv_hash_destroy(struct batadv_hashtable *hash); /** * batadv_hash_add - adds data to the hashtable * @hash: storage hash table * @compare: callback to determine if 2 hash elements are identical * @choose: callback calculating the hash index * @data: data passed to the aforementioned callbacks as argument * @data_node: to be added element * * Return: 0 on success, 1 if the element already is in the hash * and -1 on error. */ static inline int batadv_hash_add(struct batadv_hashtable *hash, batadv_hashdata_compare_cb compare, batadv_hashdata_choose_cb choose, const void *data, struct hlist_node *data_node) { u32 index; int ret = -1; struct hlist_head *head; struct hlist_node *node; spinlock_t *list_lock; /* spinlock to protect write access */ if (!hash) goto out; index = choose(data, hash->size); head = &hash->table[index]; list_lock = &hash->list_locks[index]; spin_lock_bh(list_lock); hlist_for_each(node, head) { if (!compare(node, data)) continue; ret = 1; goto unlock; } /* no duplicate found in list, add new element */ hlist_add_head_rcu(data_node, head); ret = 0; unlock: spin_unlock_bh(list_lock); out: return ret; } /* removes data from hash, if found. data could be the structure you use with * just the key filled, we just need the key for comparing. * * Return: returns pointer do data on success, so you can remove the used * structure yourself, or NULL on error */ static inline void *batadv_hash_remove(struct batadv_hashtable *hash, batadv_hashdata_compare_cb compare, batadv_hashdata_choose_cb choose, void *data) { u32 index; struct hlist_node *node; struct hlist_head *head; void *data_save = NULL; index = choose(data, hash->size); head = &hash->table[index]; spin_lock_bh(&hash->list_locks[index]); hlist_for_each(node, head) { if (!compare(node, data)) continue; data_save = node; hlist_del_rcu(node); break; } spin_unlock_bh(&hash->list_locks[index]); return data_save; } #endif /* _NET_BATMAN_ADV_HASH_H_ */ value='0' selected='selected'>includemode:
Diffstat (limited to 'include/net/ip6_checksum.h')