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 const struct nla_policy gact_policy[TCA_GACT_MAX + 1] = { 57 [TCA_GACT_PARMS] = { .len = sizeof(struct tc_gact) }, 58 [TCA_GACT_PROB] = { .len = sizeof(struct tc_gact_p) }, 59 }; 60 61 static int tcf_gact_init(struct net *net, struct nlattr *nla, 62 struct nlattr *est, struct tc_action *a, 63 int ovr, int bind) 64 { 65 struct nlattr *tb[TCA_GACT_MAX + 1]; 66 struct tc_gact *parm; 67 struct tcf_gact *gact; 68 struct tcf_common *pc; 69 int ret = 0; 70 int err; 71 #ifdef CONFIG_GACT_PROB 72 struct tc_gact_p *p_parm = NULL; 73 #endif 74 75 if (nla == NULL) 76 return -EINVAL; 77 78 err = nla_parse_nested(tb, TCA_GACT_MAX, nla, gact_policy); 79 if (err < 0) 80 return err; 81 82 if (tb[TCA_GACT_PARMS] == NULL) 83 return -EINVAL; 84 parm = nla_data(tb[TCA_GACT_PARMS]); 85 86 #ifndef CONFIG_GACT_PROB 87 if (tb[TCA_GACT_PROB] != NULL) 88 return -EOPNOTSUPP; 89 #else 90 if (tb[TCA_GACT_PROB]) { 91 p_parm = nla_data(tb[TCA_GACT_PROB]); 92 if (p_parm->ptype >= MAX_RAND) 93 return -EINVAL; 94 } 95 #endif 96 97 pc = tcf_hash_check(parm->index, a, bind, &gact_hash_info); 98 if (!pc) { 99 pc = tcf_hash_create(parm->index, est, a, sizeof(*gact), 100 bind, &gact_idx_gen, &gact_hash_info); 101 if (IS_ERR(pc)) 102 return PTR_ERR(pc); 103 ret = ACT_P_CREATED; 104 } else { 105 if (bind)/* dont override defaults */ 106 return 0; 107 tcf_hash_release(pc, bind, &gact_hash_info); 108 if (!ovr) 109 return -EEXIST; 110 } 111 112 gact = to_gact(pc); 113 114 spin_lock_bh(&gact->tcf_lock); 115 gact->tcf_action = parm->action; 116 #ifdef CONFIG_GACT_PROB 117 if (p_parm) { 118 gact->tcfg_paction = p_parm->paction; 119 gact->tcfg_pval = p_parm->pval; 120 gact->tcfg_ptype = p_parm->ptype; 121 } 122 #endif 123 spin_unlock_bh(&gact->tcf_lock); 124 if (ret == ACT_P_CREATED) 125 tcf_hash_insert(pc, &gact_hash_info); 126 return ret; 127 } 128 129 static int tcf_gact_cleanup(struct tc_action *a, int bind) 130 { 131 struct tcf_gact *gact = a->priv; 132 133 if (gact) 134 return tcf_hash_release(&gact->common, bind, &gact_hash_info); 135 return 0; 136 } 137 138 static int tcf_gact(struct sk_buff *skb, const struct tc_action *a, 139 struct tcf_result *res) 140 { 141 struct tcf_gact *gact = a->priv; 142 int action = TC_ACT_SHOT; 143 144 spin_lock(&gact->tcf_lock); 145 #ifdef CONFIG_GACT_PROB 146 if (gact->tcfg_ptype) 147 action = gact_rand[gact->tcfg_ptype](gact); 148 else 149 action = gact->tcf_action; 150 #else 151 action = gact->tcf_action; 152 #endif 153 gact->tcf_bstats.bytes += qdisc_pkt_len(skb); 154 gact->tcf_bstats.packets++; 155 if (action == TC_ACT_SHOT) 156 gact->tcf_qstats.drops++; 157 gact->tcf_tm.lastuse = jiffies; 158 spin_unlock(&gact->tcf_lock); 159 160 return action; 161 } 162 163 static int tcf_gact_dump(struct sk_buff *skb, struct tc_action *a, int bind, int ref) 164 { 165 unsigned char *b = skb_tail_pointer(skb); 166 struct tcf_gact *gact = a->priv; 167 struct tc_gact opt = { 168 .index = gact->tcf_index, 169 .refcnt = gact->tcf_refcnt - ref, 170 .bindcnt = gact->tcf_bindcnt - bind, 171 .action = gact->tcf_action, 172 }; 173 struct tcf_t t; 174 175 if (nla_put(skb, TCA_GACT_PARMS, sizeof(opt), &opt)) 176 goto nla_put_failure; 177 #ifdef CONFIG_GACT_PROB 178 if (gact->tcfg_ptype) { 179 struct tc_gact_p p_opt = { 180 .paction = gact->tcfg_paction, 181 .pval = gact->tcfg_pval, 182 .ptype = gact->tcfg_ptype, 183 }; 184 185 if (nla_put(skb, TCA_GACT_PROB, sizeof(p_opt), &p_opt)) 186 goto nla_put_failure; 187 } 188 #endif 189 t.install = jiffies_to_clock_t(jiffies - gact->tcf_tm.install); 190 t.lastuse = jiffies_to_clock_t(jiffies - gact->tcf_tm.lastuse); 191 t.expires = jiffies_to_clock_t(gact->tcf_tm.expires); 192 if (nla_put(skb, TCA_GACT_TM, sizeof(t), &t)) 193 goto nla_put_failure; 194 return skb->len; 195 196 nla_put_failure: 197 nlmsg_trim(skb, b); 198 return -1; 199 } 200 201 static struct tc_action_ops act_gact_ops = { 202 .kind = "gact", 203 .hinfo = &gact_hash_info, 204 .type = TCA_ACT_GACT, 205 .capab = TCA_CAP_NONE, 206 .owner = THIS_MODULE, 207 .act = tcf_gact, 208 .dump = tcf_gact_dump, 209 .cleanup = tcf_gact_cleanup, 210 .init = tcf_gact_init, 211 }; 212 213 MODULE_AUTHOR("Jamal Hadi Salim(2002-4)"); 214 MODULE_DESCRIPTION("Generic Classifier actions"); 215 MODULE_LICENSE("GPL"); 216 217 static int __init gact_init_module(void) 218 { 219 #ifdef CONFIG_GACT_PROB 220 pr_info("GACT probability on\n"); 221 #else 222 pr_info("GACT probability NOT on\n"); 223 #endif 224 return tcf_register_action(&act_gact_ops); 225 } 226 227 static void __exit gact_cleanup_module(void) 228 { 229 tcf_unregister_action(&act_gact_ops); 230 } 231 232 module_init(gact_init_module); 233 module_exit(gact_cleanup_module); 234