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 u32 gact_idx_gen; 28 static struct tcf_hashinfo gact_hash_info; 29 30 #ifdef CONFIG_GACT_PROB 31 static int gact_net_rand(struct tcf_gact *gact) 32 { 33 if (!gact->tcfg_pval || net_random() % gact->tcfg_pval) 34 return gact->tcf_action; 35 return gact->tcfg_paction; 36 } 37 38 static int gact_determ(struct tcf_gact *gact) 39 { 40 if (!gact->tcfg_pval || gact->tcf_bstats.packets % gact->tcfg_pval) 41 return gact->tcf_action; 42 return gact->tcfg_paction; 43 } 44 45 typedef int (*g_rand)(struct tcf_gact *gact); 46 static g_rand gact_rand[MAX_RAND] = { NULL, gact_net_rand, gact_determ }; 47 #endif /* CONFIG_GACT_PROB */ 48 49 static const struct nla_policy gact_policy[TCA_GACT_MAX + 1] = { 50 [TCA_GACT_PARMS] = { .len = sizeof(struct tc_gact) }, 51 [TCA_GACT_PROB] = { .len = sizeof(struct tc_gact_p) }, 52 }; 53 54 static int tcf_gact_init(struct net *net, struct nlattr *nla, 55 struct nlattr *est, struct tc_action *a, 56 int ovr, int bind) 57 { 58 struct nlattr *tb[TCA_GACT_MAX + 1]; 59 struct tc_gact *parm; 60 struct tcf_gact *gact; 61 struct tcf_common *pc; 62 int ret = 0; 63 int err; 64 #ifdef CONFIG_GACT_PROB 65 struct tc_gact_p *p_parm = NULL; 66 #endif 67 68 if (nla == NULL) 69 return -EINVAL; 70 71 err = nla_parse_nested(tb, TCA_GACT_MAX, nla, gact_policy); 72 if (err < 0) 73 return err; 74 75 if (tb[TCA_GACT_PARMS] == NULL) 76 return -EINVAL; 77 parm = nla_data(tb[TCA_GACT_PARMS]); 78 79 #ifndef CONFIG_GACT_PROB 80 if (tb[TCA_GACT_PROB] != NULL) 81 return -EOPNOTSUPP; 82 #else 83 if (tb[TCA_GACT_PROB]) { 84 p_parm = nla_data(tb[TCA_GACT_PROB]); 85 if (p_parm->ptype >= MAX_RAND) 86 return -EINVAL; 87 } 88 #endif 89 90 pc = tcf_hash_check(parm->index, a, bind, &gact_hash_info); 91 if (!pc) { 92 pc = tcf_hash_create(parm->index, est, a, sizeof(*gact), 93 bind, &gact_idx_gen, &gact_hash_info); 94 if (IS_ERR(pc)) 95 return PTR_ERR(pc); 96 ret = ACT_P_CREATED; 97 } else { 98 if (!ovr) { 99 tcf_hash_release(pc, bind, &gact_hash_info); 100 return -EEXIST; 101 } 102 } 103 104 gact = to_gact(pc); 105 106 spin_lock_bh(&gact->tcf_lock); 107 gact->tcf_action = parm->action; 108 #ifdef CONFIG_GACT_PROB 109 if (p_parm) { 110 gact->tcfg_paction = p_parm->paction; 111 gact->tcfg_pval = p_parm->pval; 112 gact->tcfg_ptype = p_parm->ptype; 113 } 114 #endif 115 spin_unlock_bh(&gact->tcf_lock); 116 if (ret == ACT_P_CREATED) 117 tcf_hash_insert(pc, &gact_hash_info); 118 return ret; 119 } 120 121 static int tcf_gact_cleanup(struct tc_action *a, int bind) 122 { 123 struct tcf_gact *gact = a->priv; 124 125 if (gact) 126 return tcf_hash_release(&gact->common, bind, &gact_hash_info); 127 return 0; 128 } 129 130 static int tcf_gact(struct sk_buff *skb, const struct tc_action *a, 131 struct tcf_result *res) 132 { 133 struct tcf_gact *gact = a->priv; 134 int action = TC_ACT_SHOT; 135 136 spin_lock(&gact->tcf_lock); 137 #ifdef CONFIG_GACT_PROB 138 if (gact->tcfg_ptype) 139 action = gact_rand[gact->tcfg_ptype](gact); 140 else 141 action = gact->tcf_action; 142 #else 143 action = gact->tcf_action; 144 #endif 145 gact->tcf_bstats.bytes += qdisc_pkt_len(skb); 146 gact->tcf_bstats.packets++; 147 if (action == TC_ACT_SHOT) 148 gact->tcf_qstats.drops++; 149 gact->tcf_tm.lastuse = jiffies; 150 spin_unlock(&gact->tcf_lock); 151 152 return action; 153 } 154 155 static int tcf_gact_dump(struct sk_buff *skb, struct tc_action *a, int bind, int ref) 156 { 157 unsigned char *b = skb_tail_pointer(skb); 158 struct tcf_gact *gact = a->priv; 159 struct tc_gact opt = { 160 .index = gact->tcf_index, 161 .refcnt = gact->tcf_refcnt - ref, 162 .bindcnt = gact->tcf_bindcnt - bind, 163 .action = gact->tcf_action, 164 }; 165 struct tcf_t t; 166 167 if (nla_put(skb, TCA_GACT_PARMS, sizeof(opt), &opt)) 168 goto nla_put_failure; 169 #ifdef CONFIG_GACT_PROB 170 if (gact->tcfg_ptype) { 171 struct tc_gact_p p_opt = { 172 .paction = gact->tcfg_paction, 173 .pval = gact->tcfg_pval, 174 .ptype = gact->tcfg_ptype, 175 }; 176 177 if (nla_put(skb, TCA_GACT_PROB, sizeof(p_opt), &p_opt)) 178 goto nla_put_failure; 179 } 180 #endif 181 t.install = jiffies_to_clock_t(jiffies - gact->tcf_tm.install); 182 t.lastuse = jiffies_to_clock_t(jiffies - gact->tcf_tm.lastuse); 183 t.expires = jiffies_to_clock_t(gact->tcf_tm.expires); 184 if (nla_put(skb, TCA_GACT_TM, sizeof(t), &t)) 185 goto nla_put_failure; 186 return skb->len; 187 188 nla_put_failure: 189 nlmsg_trim(skb, b); 190 return -1; 191 } 192 193 static struct tc_action_ops act_gact_ops = { 194 .kind = "gact", 195 .hinfo = &gact_hash_info, 196 .type = TCA_ACT_GACT, 197 .capab = TCA_CAP_NONE, 198 .owner = THIS_MODULE, 199 .act = tcf_gact, 200 .dump = tcf_gact_dump, 201 .cleanup = tcf_gact_cleanup, 202 .init = tcf_gact_init, 203 }; 204 205 MODULE_AUTHOR("Jamal Hadi Salim(2002-4)"); 206 MODULE_DESCRIPTION("Generic Classifier actions"); 207 MODULE_LICENSE("GPL"); 208 209 static int __init gact_init_module(void) 210 { 211 int err = tcf_hashinfo_init(&gact_hash_info, GACT_TAB_MASK); 212 if (err) 213 return err; 214 #ifdef CONFIG_GACT_PROB 215 pr_info("GACT probability on\n"); 216 #else 217 pr_info("GACT probability NOT on\n"); 218 #endif 219 return tcf_register_action(&act_gact_ops); 220 } 221 222 static void __exit gact_cleanup_module(void) 223 { 224 tcf_unregister_action(&act_gact_ops); 225 tcf_hashinfo_destroy(&gact_hash_info); 226 } 227 228 module_init(gact_init_module); 229 module_exit(gact_cleanup_module); 230