[linux.git] / net / ipv4 / multipath.c

/* multipath.c: IPV4 multipath algorithm support.
 *
 * Copyright (C) 2004, 2005 Einar Lueck <[email protected]>
 * Copyright (C) 2005 David S. Miller <[email protected]>
 */

#include <linux/module.h>
#include <linux/errno.h>
#include <linux/netdevice.h>
#include <linux/spinlock.h>

#include <net/ip_mp_alg.h>

static DEFINE_SPINLOCK(alg_table_lock);
struct ip_mp_alg_ops *ip_mp_alg_table[IP_MP_ALG_MAX + 1];

int multipath_alg_register(struct ip_mp_alg_ops *ops, enum ip_mp_alg n)
{
	struct ip_mp_alg_ops **slot;
	int err;

	if (n < IP_MP_ALG_NONE || n > IP_MP_ALG_MAX ||
	    !ops->mp_alg_select_route)
		return -EINVAL;

	spin_lock(&alg_table_lock);
	slot = &ip_mp_alg_table[n];
	if (*slot != NULL) {
		err = -EBUSY;
	} else {
		*slot = ops;
		err = 0;
	}
	spin_unlock(&alg_table_lock);

	return err;
}
EXPORT_SYMBOL(multipath_alg_register);

void multipath_alg_unregister(struct ip_mp_alg_ops *ops, enum ip_mp_alg n)
{
	struct ip_mp_alg_ops **slot;

	if (n < IP_MP_ALG_NONE || n > IP_MP_ALG_MAX)
		return;

	spin_lock(&alg_table_lock);
	slot = &ip_mp_alg_table[n];
	if (*slot == ops)
		*slot = NULL;
	spin_unlock(&alg_table_lock);

	synchronize_net();
}
EXPORT_SYMBOL(multipath_alg_unregister);
Commit	Line	Data
1da177e4 LT	1	/* multipath.c: IPV4 multipath algorithm support.
	2	*
	3	* Copyright (C) 2004, 2005 Einar Lueck <[email protected]>
	4	* Copyright (C) 2005 David S. Miller <[email protected]>
	5	*/
	6
	7	#include <linux/module.h>
	8	#include <linux/errno.h>
	9	#include <linux/netdevice.h>
	10	#include <linux/spinlock.h>
	11
	12	#include <net/ip_mp_alg.h>
	13
	14	static DEFINE_SPINLOCK(alg_table_lock);
	15	struct ip_mp_alg_ops *ip_mp_alg_table[IP_MP_ALG_MAX + 1];
	16
	17	int multipath_alg_register(struct ip_mp_alg_ops *ops, enum ip_mp_alg n)
	18	{
	19	struct ip_mp_alg_ops **slot;
	20	int err;
	21
	22	if (n < IP_MP_ALG_NONE \|\| n > IP_MP_ALG_MAX \|\|
	23	!ops->mp_alg_select_route)
	24	return -EINVAL;
	25
	26	spin_lock(&alg_table_lock);
	27	slot = &ip_mp_alg_table[n];
	28	if (*slot != NULL) {
	29	err = -EBUSY;
	30	} else {
	31	*slot = ops;
	32	err = 0;
	33	}
	34	spin_unlock(&alg_table_lock);
	35
	36	return err;
	37	}
	38	EXPORT_SYMBOL(multipath_alg_register);
	39
	40	void multipath_alg_unregister(struct ip_mp_alg_ops *ops, enum ip_mp_alg n)
	41	{
	42	struct ip_mp_alg_ops **slot;
	43
	44	if (n < IP_MP_ALG_NONE \|\| n > IP_MP_ALG_MAX)
	45	return;
	46
	47	spin_lock(&alg_table_lock);
	48	slot = &ip_mp_alg_table[n];
	49	if (*slot == ops)
	50	*slot = NULL;
	51	spin_unlock(&alg_table_lock);
	52
	53	synchronize_net();
	54	}
	55	EXPORT_SYMBOL(multipath_alg_unregister);