1 /* 2 * net/sched/gact.c Generic actions 3 * 4 * This program is free software; you can redistribute it and/or 5 * modify it under the terms of the GNU General Public License 6 * as published by the Free Software Foundation; either version 7 * 2 of the License, or (at your option) any later version. 8 * 9 * copyright Jamal Hadi Salim (2002-4) 10 * 11 */ 12 13 #include <asm/uaccess.h> 14 #include <asm/system.h> 15 #include <linux/bitops.h> 16 #include <linux/types.h> 17 #include <linux/kernel.h> 18 #include <linux/string.h> 19 #include <linux/mm.h> 20 #include <linux/socket.h> 21 #include <linux/sockios.h> 22 #include <linux/in.h> 23 #include <linux/errno.h> 24 #include <linux/interrupt.h> 25 #include <linux/netdevice.h> 26 #include <linux/skbuff.h> 27 #include <linux/rtnetlink.h> 28 #include <linux/module.h> 29 #include <linux/init.h> 30 #include <linux/proc_fs.h> 31 #include <net/sock.h> 32 #include <net/pkt_sched.h> 33 #include <linux/tc_act/tc_gact.h> 34 #include <net/tc_act/tc_gact.h> 35 36 #define GACT_TAB_MASK 15 37 static struct tcf_common *tcf_gact_ht[GACT_TAB_MASK + 1]; 38 static u32 gact_idx_gen; 39 static DEFINE_RWLOCK(gact_lock); 40 41 static struct tcf_hashinfo gact_hash_info = { 42 .htab = tcf_gact_ht, 43 .hmask = GACT_TAB_MASK, 44 .lock = &gact_lock, 45 }; 46 47 #ifdef CONFIG_GACT_PROB 48 static int gact_net_rand(struct tcf_gact *gact) 49 { 50 if (!gact->tcfg_pval || net_random() % gact->tcfg_pval) 51 return gact->tcf_action; 52 return gact->tcfg_paction; 53 } 54 55 static int gact_determ(struct tcf_gact *gact) 56 { 57 if (!gact->tcfg_pval || gact->tcf_bstats.packets % gact->tcfg_pval) 58 return gact->tcf_action; 59 return gact->tcfg_paction; 60 } 61 62 typedef int (*g_rand)(struct tcf_gact *gact); 63 static g_rand gact_rand[MAX_RAND]= { NULL, gact_net_rand, gact_determ }; 64 #endif /* CONFIG_GACT_PROB */ 65 66 static int tcf_gact_init(struct rtattr *rta, struct rtattr *est, 67 struct tc_action *a, int ovr, int bind) 68 { 69 struct rtattr *tb[TCA_GACT_MAX]; 70 struct tc_gact *parm; 71 struct tcf_gact *gact; 72 struct tcf_common *pc; 73 int ret = 0; 74 75 if (rta == NULL || rtattr_parse_nested(tb, TCA_GACT_MAX, rta) < 0) 76 return -EINVAL; 77 78 if (tb[TCA_GACT_PARMS - 1] == NULL || 79 RTA_PAYLOAD(tb[TCA_GACT_PARMS - 1]) < sizeof(*parm)) 80 return -EINVAL; 81 parm = RTA_DATA(tb[TCA_GACT_PARMS - 1]); 82 83 if (tb[TCA_GACT_PROB-1] != NULL) 84 #ifdef CONFIG_GACT_PROB 85 if (RTA_PAYLOAD(tb[TCA_GACT_PROB-1]) < sizeof(struct tc_gact_p)) 86 return -EINVAL; 87 #else 88 return -EOPNOTSUPP; 89 #endif 90 91 pc = tcf_hash_check(parm->index, a, bind, &gact_hash_info); 92 if (!pc) { 93 pc = tcf_hash_create(parm->index, est, a, sizeof(*gact), 94 bind, &gact_idx_gen, &gact_hash_info); 95 if (unlikely(!pc)) 96 return -ENOMEM; 97 ret = ACT_P_CREATED; 98 } else { 99 if (!ovr) { 100 tcf_hash_release(pc, bind, &gact_hash_info); 101 return -EEXIST; 102 } 103 } 104 105 gact = to_gact(pc); 106 107 spin_lock_bh(&gact->tcf_lock); 108 gact->tcf_action = parm->action; 109 #ifdef CONFIG_GACT_PROB 110 if (tb[TCA_GACT_PROB-1] != NULL) { 111 struct tc_gact_p *p_parm = RTA_DATA(tb[TCA_GACT_PROB-1]); 112 gact->tcfg_paction = p_parm->paction; 113 gact->tcfg_pval = p_parm->pval; 114 gact->tcfg_ptype = p_parm->ptype; 115 } 116 #endif 117 spin_unlock_bh(&gact->tcf_lock); 118 if (ret == ACT_P_CREATED) 119 tcf_hash_insert(pc, &gact_hash_info); 120 return ret; 121 } 122 123 static int tcf_gact_cleanup(struct tc_action *a, int bind) 124 { 125 struct tcf_gact *gact = a->priv; 126 127 if (gact) 128 return tcf_hash_release(&gact->common, bind, &gact_hash_info); 129 return 0; 130 } 131 132 static int tcf_gact(struct sk_buff *skb, struct tc_action *a, struct tcf_result *res) 133 { 134 struct tcf_gact *gact = a->priv; 135 int action = TC_ACT_SHOT; 136 137 spin_lock(&gact->tcf_lock); 138 #ifdef CONFIG_GACT_PROB 139 if (gact->tcfg_ptype && gact_rand[gact->tcfg_ptype] != NULL) 140 action = gact_rand[gact->tcfg_ptype](gact); 141 else 142 action = gact->tcf_action; 143 #else 144 action = gact->tcf_action; 145 #endif 146 gact->tcf_bstats.bytes += skb->len; 147 gact->tcf_bstats.packets++; 148 if (action == TC_ACT_SHOT) 149 gact->tcf_qstats.drops++; 150 gact->tcf_tm.lastuse = jiffies; 151 spin_unlock(&gact->tcf_lock); 152 153 return action; 154 } 155 156 static int tcf_gact_dump(struct sk_buff *skb, struct tc_action *a, int bind, int ref) 157 { 158 unsigned char *b = skb->tail; 159 struct tc_gact opt; 160 struct tcf_gact *gact = a->priv; 161 struct tcf_t t; 162 163 opt.index = gact->tcf_index; 164 opt.refcnt = gact->tcf_refcnt - ref; 165 opt.bindcnt = gact->tcf_bindcnt - bind; 166 opt.action = gact->tcf_action; 167 RTA_PUT(skb, TCA_GACT_PARMS, sizeof(opt), &opt); 168 #ifdef CONFIG_GACT_PROB 169 if (gact->tcfg_ptype) { 170 struct tc_gact_p p_opt; 171 p_opt.paction = gact->tcfg_paction; 172 p_opt.pval = gact->tcfg_pval; 173 p_opt.ptype = gact->tcfg_ptype; 174 RTA_PUT(skb, TCA_GACT_PROB, sizeof(p_opt), &p_opt); 175 } 176 #endif 177 t.install = jiffies_to_clock_t(jiffies - gact->tcf_tm.install); 178 t.lastuse = jiffies_to_clock_t(jiffies - gact->tcf_tm.lastuse); 179 t.expires = jiffies_to_clock_t(gact->tcf_tm.expires); 180 RTA_PUT(skb, TCA_GACT_TM, sizeof(t), &t); 181 return skb->len; 182 183 rtattr_failure: 184 skb_trim(skb, b - skb->data); 185 return -1; 186 } 187 188 static struct tc_action_ops act_gact_ops = { 189 .kind = "gact", 190 .hinfo = &gact_hash_info, 191 .type = TCA_ACT_GACT, 192 .capab = TCA_CAP_NONE, 193 .owner = THIS_MODULE, 194 .act = tcf_gact, 195 .dump = tcf_gact_dump, 196 .cleanup = tcf_gact_cleanup, 197 .lookup = tcf_hash_search, 198 .init = tcf_gact_init, 199 .walk = tcf_generic_walker 200 }; 201 202 MODULE_AUTHOR("Jamal Hadi Salim(2002-4)"); 203 MODULE_DESCRIPTION("Generic Classifier actions"); 204 MODULE_LICENSE("GPL"); 205 206 static int __init gact_init_module(void) 207 { 208 #ifdef CONFIG_GACT_PROB 209 printk("GACT probability on\n"); 210 #else 211 printk("GACT probability NOT on\n"); 212 #endif 213 return tcf_register_action(&act_gact_ops); 214 } 215 216 static void __exit gact_cleanup_module(void) 217 { 218 tcf_unregister_action(&act_gact_ops); 219 } 220 221 module_init(gact_init_module); 222 module_exit(gact_cleanup_module); 223