[deliverable/linux.git] / net / batman-adv / originator.h

/*
 * Copyright (C) 2007-2011 B.A.T.M.A.N. contributors:
 *
 * Marek Lindner, Simon Wunderlich
 *
 * 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
 *
 */

#ifndef _NET_BATMAN_ADV_ORIGINATOR_H_
#define _NET_BATMAN_ADV_ORIGINATOR_H_

#include "hash.h"

int originator_init(struct bat_priv *bat_priv);
void originator_free(struct bat_priv *bat_priv);
void purge_orig_ref(struct bat_priv *bat_priv);
void orig_node_free_ref(struct orig_node *orig_node);
struct orig_node *get_orig_node(struct bat_priv *bat_priv, uint8_t *addr);
struct neigh_node *create_neighbor(struct orig_node *orig_node,
				   struct orig_node *orig_neigh_node,
				   uint8_t *neigh,
				   struct hard_iface *if_incoming);
void neigh_node_free_ref(struct neigh_node *neigh_node);
int orig_seq_print_text(struct seq_file *seq, void *offset);
int orig_hash_add_if(struct hard_iface *hard_iface, int max_if_num);
int orig_hash_del_if(struct hard_iface *hard_iface, int max_if_num);


/* returns 1 if they are the same originator */
static inline int compare_orig(struct hlist_node *node, void *data2)
{
	void *data1 = container_of(node, struct orig_node, hash_entry);

	return (memcmp(data1, data2, ETH_ALEN) == 0 ? 1 : 0);
}

/* hashfunction to choose an entry in a hash table of given size */
/* hash algorithm from http://en.wikipedia.org/wiki/Hash_table */
static inline int choose_orig(void *data, int32_t size)
{
	unsigned char *key = data;
	uint32_t hash = 0;
	size_t i;

	for (i = 0; i < 6; i++) {
		hash += key[i];
		hash += (hash << 10);
		hash ^= (hash >> 6);
	}

	hash += (hash << 3);
	hash ^= (hash >> 11);
	hash += (hash << 15);

	return hash % size;
}

static inline struct orig_node *orig_hash_find(struct bat_priv *bat_priv,
					       void *data)
{
	struct hashtable_t *hash = bat_priv->orig_hash;
	struct hlist_head *head;
	struct hlist_node *node;
	struct orig_node *orig_node, *orig_node_tmp = NULL;
	int index;

	if (!hash)
		return NULL;

	index = choose_orig(data, hash->size);
	head = &hash->table[index];

	rcu_read_lock();
	hlist_for_each_entry_rcu(orig_node, node, head, hash_entry) {
		if (!compare_eth(orig_node, data))
			continue;

		if (!atomic_inc_not_zero(&orig_node->refcount))
			continue;

		orig_node_tmp = orig_node;
		break;
	}
	rcu_read_unlock();

	return orig_node_tmp;
}

#endif /* _NET_BATMAN_ADV_ORIGINATOR_H_ */
Commit	Line	Data
c6c8fea2	1	/*
64afe353	2	* Copyright (C) 2007-2011 B.A.T.M.A.N. contributors:
c6c8fea2 SE	3	*
	4	* Marek Lindner, Simon Wunderlich
	5	*
	6	* This program is free software; you can redistribute it and/or
	7	* modify it under the terms of version 2 of the GNU General Public
	8	* License as published by the Free Software Foundation.
	9	*
	10	* This program is distributed in the hope that it will be useful, but
	11	* WITHOUT ANY WARRANTY; without even the implied warranty of
	12	* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
	13	* General Public License for more details.
	14	*
	15	* You should have received a copy of the GNU General Public License
	16	* along with this program; if not, write to the Free Software
	17	* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
	18	* 02110-1301, USA
	19	*
	20	*/
	21
	22	#ifndef _NET_BATMAN_ADV_ORIGINATOR_H_
	23	#define _NET_BATMAN_ADV_ORIGINATOR_H_
	24
7aadf889 ML	25	#include "hash.h"
7aadf889 ML	26
c6c8fea2 SE	27	int originator_init(struct bat_priv *bat_priv);
	28	void originator_free(struct bat_priv *bat_priv);
	29	void purge_orig_ref(struct bat_priv *bat_priv);
7b36e8ee	30	void orig_node_free_ref(struct orig_node *orig_node);
c6c8fea2	31	struct orig_node get_orig_node(struct bat_priv bat_priv, uint8_t *addr);
a8e7f4bc ML	32	struct neigh_node create_neighbor(struct orig_node orig_node,
	33	struct orig_node *orig_neigh_node,
	34	uint8_t *neigh,
e6c10f43	35	struct hard_iface *if_incoming);
44524fcd	36	void neigh_node_free_ref(struct neigh_node *neigh_node);
c6c8fea2	37	int orig_seq_print_text(struct seq_file seq, void offset);
e6c10f43 ML	38	int orig_hash_add_if(struct hard_iface *hard_iface, int max_if_num);
e6c10f43 ML	39	int orig_hash_del_if(struct hard_iface *hard_iface, int max_if_num);
c6c8fea2 SE	40
	41
	42	/* returns 1 if they are the same originator */
7aadf889	43	static inline int compare_orig(struct hlist_node node, void data2)
c6c8fea2	44	{
7aadf889 ML	45	void *data1 = container_of(node, struct orig_node, hash_entry);
7aadf889 ML	46
c6c8fea2 SE	47	return (memcmp(data1, data2, ETH_ALEN) == 0 ? 1 : 0);
	48	}
	49
	50	/* hashfunction to choose an entry in a hash table of given size */
	51	/* hash algorithm from http://en.wikipedia.org/wiki/Hash_table */
	52	static inline int choose_orig(void *data, int32_t size)
	53	{
	54	unsigned char *key = data;
	55	uint32_t hash = 0;
	56	size_t i;
	57
	58	for (i = 0; i < 6; i++) {
	59	hash += key[i];
	60	hash += (hash << 10);
	61	hash ^= (hash >> 6);
	62	}
	63
	64	hash += (hash << 3);
	65	hash ^= (hash >> 11);
	66	hash += (hash << 15);
	67
	68	return hash % size;
	69	}
	70
7aadf889 ML	71	static inline struct orig_node orig_hash_find(struct bat_priv bat_priv,
	72	void *data)
	73	{
	74	struct hashtable_t *hash = bat_priv->orig_hash;
	75	struct hlist_head *head;
	76	struct hlist_node *node;
	77	struct orig_node orig_node, orig_node_tmp = NULL;
	78	int index;
	79
	80	if (!hash)
	81	return NULL;
	82
	83	index = choose_orig(data, hash->size);
	84	head = &hash->table[index];
	85
	86	rcu_read_lock();
	87	hlist_for_each_entry_rcu(orig_node, node, head, hash_entry) {
	88	if (!compare_eth(orig_node, data))
	89	continue;
	90
7b36e8ee ML	91	if (!atomic_inc_not_zero(&orig_node->refcount))
	92	continue;
	93
7aadf889	94	orig_node_tmp = orig_node;
7aadf889 ML	95	break;
	96	}
	97	rcu_read_unlock();
	98
	99	return orig_node_tmp;
	100	}
	101
c6c8fea2	102	#endif /* _NET_BATMAN_ADV_ORIGINATOR_H_ */