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_hashinfo gact_hash_info; 28 29 #ifdef CONFIG_GACT_PROB 30 static int gact_net_rand(struct tcf_gact *gact) 31 { 32 if (!gact->tcfg_pval || prandom_u32() % gact->tcfg_pval) 33 return gact->tcf_action; 34 return gact->tcfg_paction; 35 } 36 37 static int gact_determ(struct tcf_gact *gact) 38 { 39 if (!gact->tcfg_pval || gact->tcf_bstats.packets % gact->tcfg_pval) 40 return gact->tcf_action; 41 return gact->tcfg_paction; 42 } 43 44 typedef int (*g_rand)(struct tcf_gact *gact); 45 static g_rand gact_rand[MAX_RAND] = { NULL, gact_net_rand, gact_determ }; 46 #endif /* CONFIG_GACT_PROB */ 47 48 static const struct nla_policy gact_policy[TCA_GACT_MAX + 1] = { 49 [TCA_GACT_PARMS] = { .len = sizeof(struct tc_gact) }, 50 [TCA_GACT_PROB] = { .len = sizeof(struct tc_gact_p) }, 51 }; 52 53 static int tcf_gact_init(struct net *net, struct nlattr *nla, 54 struct nlattr *est, struct tc_action *a, 55 int ovr, int bind) 56 { 57 struct nlattr *tb[TCA_GACT_MAX + 1]; 58 struct tc_gact *parm; 59 struct tcf_gact *gact; 60 struct tcf_common *pc; 61 int ret = 0; 62 int err; 63 #ifdef CONFIG_GACT_PROB 64 struct tc_gact_p *p_parm = NULL; 65 #endif 66 67 if (nla == NULL) 68 return -EINVAL; 69 70 err = nla_parse_nested(tb, TCA_GACT_MAX, nla, gact_policy); 71 if (err < 0) 72 return err; 73 74 if (tb[TCA_GACT_PARMS] == NULL) 75 return -EINVAL; 76 parm = nla_data(tb[TCA_GACT_PARMS]); 77 78 #ifndef CONFIG_GACT_PROB 79 if (tb[TCA_GACT_PROB] != NULL) 80 return -EOPNOTSUPP; 81 #else 82 if (tb[TCA_GACT_PROB]) { 83 p_parm = nla_data(tb[TCA_GACT_PROB]); 84 if (p_parm->ptype >= MAX_RAND) 85 return -EINVAL; 86 } 87 #endif 88 89 pc = tcf_hash_check(parm->index, a, bind); 90 if (!pc) { 91 pc = tcf_hash_create(parm->index, est, a, sizeof(*gact), bind); 92 if (IS_ERR(pc)) 93 return PTR_ERR(pc); 94 ret = ACT_P_CREATED; 95 } else { 96 if (bind)/* dont override defaults */ 97 return 0; 98 tcf_hash_release(pc, bind, a->ops->hinfo); 99 if (!ovr) 100 return -EEXIST; 101 } 102 103 gact = to_gact(pc); 104 105 spin_lock_bh(&gact->tcf_lock); 106 gact->tcf_action = parm->action; 107 #ifdef CONFIG_GACT_PROB 108 if (p_parm) { 109 gact->tcfg_paction = p_parm->paction; 110 gact->tcfg_pval = p_parm->pval; 111 gact->tcfg_ptype = p_parm->ptype; 112 } 113 #endif 114 spin_unlock_bh(&gact->tcf_lock); 115 if (ret == ACT_P_CREATED) 116 tcf_hash_insert(pc, a->ops->hinfo); 117 return ret; 118 } 119 120 static int tcf_gact_cleanup(struct tc_action *a, int bind) 121 { 122 struct tcf_gact *gact = a->priv; 123 124 if (gact) 125 return tcf_hash_release(&gact->common, bind, a->ops->hinfo); 126 return 0; 127 } 128 129 static int tcf_gact(struct sk_buff *skb, const struct tc_action *a, 130 struct tcf_result *res) 131 { 132 struct tcf_gact *gact = a->priv; 133 int action = TC_ACT_SHOT; 134 135 spin_lock(&gact->tcf_lock); 136 #ifdef CONFIG_GACT_PROB 137 if (gact->tcfg_ptype) 138 action = gact_rand[gact->tcfg_ptype](gact); 139 else 140 action = gact->tcf_action; 141 #else 142 action = gact->tcf_action; 143 #endif 144 gact->tcf_bstats.bytes += qdisc_pkt_len(skb); 145 gact->tcf_bstats.packets++; 146 if (action == TC_ACT_SHOT) 147 gact->tcf_qstats.drops++; 148 gact->tcf_tm.lastuse = jiffies; 149 spin_unlock(&gact->tcf_lock); 150 151 return action; 152 } 153 154 static int tcf_gact_dump(struct sk_buff *skb, struct tc_action *a, int bind, int ref) 155 { 156 unsigned char *b = skb_tail_pointer(skb); 157 struct tcf_gact *gact = a->priv; 158 struct tc_gact opt = { 159 .index = gact->tcf_index, 160 .refcnt = gact->tcf_refcnt - ref, 161 .bindcnt = gact->tcf_bindcnt - bind, 162 .action = gact->tcf_action, 163 }; 164 struct tcf_t t; 165 166 if (nla_put(skb, TCA_GACT_PARMS, sizeof(opt), &opt)) 167 goto nla_put_failure; 168 #ifdef CONFIG_GACT_PROB 169 if (gact->tcfg_ptype) { 170 struct tc_gact_p p_opt = { 171 .paction = gact->tcfg_paction, 172 .pval = gact->tcfg_pval, 173 .ptype = gact->tcfg_ptype, 174 }; 175 176 if (nla_put(skb, TCA_GACT_PROB, sizeof(p_opt), &p_opt)) 177 goto nla_put_failure; 178 } 179 #endif 180 t.install = jiffies_to_clock_t(jiffies - gact->tcf_tm.install); 181 t.lastuse = jiffies_to_clock_t(jiffies - gact->tcf_tm.lastuse); 182 t.expires = jiffies_to_clock_t(gact->tcf_tm.expires); 183 if (nla_put(skb, TCA_GACT_TM, sizeof(t), &t)) 184 goto nla_put_failure; 185 return skb->len; 186 187 nla_put_failure: 188 nlmsg_trim(skb, b); 189 return -1; 190 } 191 192 static struct tc_action_ops act_gact_ops = { 193 .kind = "gact", 194 .hinfo = &gact_hash_info, 195 .type = TCA_ACT_GACT, 196 .owner = THIS_MODULE, 197 .act = tcf_gact, 198 .dump = tcf_gact_dump, 199 .cleanup = tcf_gact_cleanup, 200 .init = tcf_gact_init, 201 }; 202 203 MODULE_AUTHOR("Jamal Hadi Salim(2002-4)"); 204 MODULE_DESCRIPTION("Generic Classifier actions"); 205 MODULE_LICENSE("GPL"); 206 207 static int __init gact_init_module(void) 208 { 209 int err = tcf_hashinfo_init(&gact_hash_info, GACT_TAB_MASK); 210 if (err) 211 return err; 212 #ifdef CONFIG_GACT_PROB 213 pr_info("GACT probability on\n"); 214 #else 215 pr_info("GACT probability NOT on\n"); 216 #endif 217 return tcf_register_action(&act_gact_ops); 218 } 219 220 static void __exit gact_cleanup_module(void) 221 { 222 tcf_unregister_action(&act_gact_ops); 223 tcf_hashinfo_destroy(&gact_hash_info); 224 } 225 226 module_init(gact_init_module); 227 module_exit(gact_cleanup_module); 228