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 22 MODULE_LICENSE("GPL"); 23 MODULE_AUTHOR("Eric Dumazet <eric.dumazet@gmail.com>"); 24 MODULE_DESCRIPTION("Xtables: CPU match"); 25 MODULE_ALIAS("ipt_cpu"); 26 MODULE_ALIAS("ip6t_cpu"); 27 28 static 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 37 static 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 44 static 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 54 static int __init cpu_mt_init(void) 55 { 56 return xt_register_match(&cpu_mt_reg); 57 } 58 59 static void __exit cpu_mt_exit(void) 60 { 61 xt_unregister_match(&cpu_mt_reg); 62 } 63 64 module_init(cpu_mt_init); 65 module_exit(cpu_mt_exit); 66