/* multipath.c: IPV4 multipath algorithm support. * * Copyright (C) 2004, 2005 Einar Lueck <elueck@de.ibm.com> * Copyright (C) 2005 David S. Miller <davem@davemloft.net> */ #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);