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