1/* Kernel module to match running CPU */ 2 3/* 4 * Might be used to distribute connections on several daemons, if 5 * RPS (Remote Packet Steering) is enabled or NIC is multiqueue capable, 6 * each RX queue IRQ affined to one CPU (1:1 mapping) 7 * 8 */ 9 10/* (C) 2010 Eric Dumazet 11 * 12 * This program is free software; you can redistribute it and/or modify 13 * it under the terms of the GNU General Public License version 2 as 14 * published by the Free Software Foundation. 15 */ 16 17#include <linux/module.h> 18#include <linux/skbuff.h> 19#include <linux/netfilter/xt_cpu.h> 20#include <linux/netfilter/x_tables.h> 21 22MODULE_LICENSE("GPL"); 23MODULE_AUTHOR("Eric Dumazet <eric.dumazet@gmail.com>"); 24MODULE_DESCRIPTION("Xtables: CPU match"); 25MODULE_ALIAS("ipt_cpu"); 26MODULE_ALIAS("ip6t_cpu"); 27 28static int cpu_mt_check(const struct xt_mtchk_param *par) 29{ 30 const struct xt_cpu_info *info = par->matchinfo; 31 32 if (info->invert & ~1) 33 return -EINVAL; 34 return 0; 35} 36 37static bool cpu_mt(const struct sk_buff *skb, struct xt_action_param *par) 38{ 39 const struct xt_cpu_info *info = par->matchinfo; 40 41 return (info->cpu == smp_processor_id()) ^ info->invert; 42} 43 44static struct xt_match cpu_mt_reg __read_mostly = { 45 .name = "cpu", 46 .revision = 0, 47 .family = NFPROTO_UNSPEC, 48 .checkentry = cpu_mt_check, 49 .match = cpu_mt, 50 .matchsize = sizeof(struct xt_cpu_info), 51 .me = THIS_MODULE, 52}; 53 54static int __init cpu_mt_init(void) 55{ 56 return xt_register_match(&cpu_mt_reg); 57} 58 59static void __exit cpu_mt_exit(void) 60{ 61 xt_unregister_match(&cpu_mt_reg); 62} 63 64module_init(cpu_mt_init); 65module_exit(cpu_mt_exit); 66