2 * net/sched/act_gact.c Generic actions
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.
9 * copyright Jamal Hadi Salim (2002-4)
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>
26 #define GACT_TAB_MASK 15
28 static int gact_net_id;
30 #ifdef CONFIG_GACT_PROB
31 static int gact_net_rand(struct tcf_gact *gact)
33 smp_rmb(); /* coupled with smp_wmb() in tcf_gact_init() */
34 if (prandom_u32() % gact->tcfg_pval)
35 return gact->tcf_action;
36 return gact->tcfg_paction;
39 static int gact_determ(struct tcf_gact *gact)
41 u32 pack = atomic_inc_return(&gact->packets);
43 smp_rmb(); /* coupled with smp_wmb() in tcf_gact_init() */
44 if (pack % gact->tcfg_pval)
45 return gact->tcf_action;
46 return gact->tcfg_paction;
49 typedef int (*g_rand)(struct tcf_gact *gact);
50 static g_rand gact_rand[MAX_RAND] = { NULL, gact_net_rand, gact_determ };
51 #endif /* CONFIG_GACT_PROB */
53 static const struct nla_policy gact_policy[TCA_GACT_MAX + 1] = {
54 [TCA_GACT_PARMS] = { .len = sizeof(struct tc_gact) },
55 [TCA_GACT_PROB] = { .len = sizeof(struct tc_gact_p) },
58 static int tcf_gact_init(struct net *net, struct nlattr *nla,
59 struct nlattr *est, struct tc_action *a,
62 struct tc_action_net *tn = net_generic(net, gact_net_id);
63 struct nlattr *tb[TCA_GACT_MAX + 1];
65 struct tcf_gact *gact;
68 #ifdef CONFIG_GACT_PROB
69 struct tc_gact_p *p_parm = NULL;
75 err = nla_parse_nested(tb, TCA_GACT_MAX, nla, gact_policy);
79 if (tb[TCA_GACT_PARMS] == NULL)
81 parm = nla_data(tb[TCA_GACT_PARMS]);
83 #ifndef CONFIG_GACT_PROB
84 if (tb[TCA_GACT_PROB] != NULL)
87 if (tb[TCA_GACT_PROB]) {
88 p_parm = nla_data(tb[TCA_GACT_PROB]);
89 if (p_parm->ptype >= MAX_RAND)
94 if (!tcf_hash_check(tn, parm->index, a, bind)) {
95 ret = tcf_hash_create(tn, parm->index, est, a,
96 sizeof(*gact), bind, true);
101 if (bind)/* dont override defaults */
103 tcf_hash_release(a, bind);
111 gact->tcf_action = parm->action;
112 #ifdef CONFIG_GACT_PROB
114 gact->tcfg_paction = p_parm->paction;
115 gact->tcfg_pval = max_t(u16, 1, p_parm->pval);
116 /* Make sure tcfg_pval is written before tcfg_ptype
117 * coupled with smp_rmb() in gact_net_rand() & gact_determ()
120 gact->tcfg_ptype = p_parm->ptype;
123 if (ret == ACT_P_CREATED)
124 tcf_hash_insert(tn, a);
128 static int tcf_gact(struct sk_buff *skb, const struct tc_action *a,
129 struct tcf_result *res)
131 struct tcf_gact *gact = a->priv;
132 int action = READ_ONCE(gact->tcf_action);
134 #ifdef CONFIG_GACT_PROB
136 u32 ptype = READ_ONCE(gact->tcfg_ptype);
139 action = gact_rand[ptype](gact);
142 bstats_cpu_update(this_cpu_ptr(gact->common.cpu_bstats), skb);
143 if (action == TC_ACT_SHOT)
144 qstats_drop_inc(this_cpu_ptr(gact->common.cpu_qstats));
146 tcf_lastuse_update(&gact->tcf_tm);
151 static int tcf_gact_dump(struct sk_buff *skb, struct tc_action *a, int bind, int ref)
153 unsigned char *b = skb_tail_pointer(skb);
154 struct tcf_gact *gact = a->priv;
155 struct tc_gact opt = {
156 .index = gact->tcf_index,
157 .refcnt = gact->tcf_refcnt - ref,
158 .bindcnt = gact->tcf_bindcnt - bind,
159 .action = gact->tcf_action,
163 if (nla_put(skb, TCA_GACT_PARMS, sizeof(opt), &opt))
164 goto nla_put_failure;
165 #ifdef CONFIG_GACT_PROB
166 if (gact->tcfg_ptype) {
167 struct tc_gact_p p_opt = {
168 .paction = gact->tcfg_paction,
169 .pval = gact->tcfg_pval,
170 .ptype = gact->tcfg_ptype,
173 if (nla_put(skb, TCA_GACT_PROB, sizeof(p_opt), &p_opt))
174 goto nla_put_failure;
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 if (nla_put(skb, TCA_GACT_TM, sizeof(t), &t))
181 goto nla_put_failure;
189 static int tcf_gact_walker(struct net *net, struct sk_buff *skb,
190 struct netlink_callback *cb, int type,
193 struct tc_action_net *tn = net_generic(net, gact_net_id);
195 return tcf_generic_walker(tn, skb, cb, type, a);
198 static int tcf_gact_search(struct net *net, struct tc_action *a, u32 index)
200 struct tc_action_net *tn = net_generic(net, gact_net_id);
202 return tcf_hash_search(tn, a, index);
205 static struct tc_action_ops act_gact_ops = {
207 .type = TCA_ACT_GACT,
208 .owner = THIS_MODULE,
210 .dump = tcf_gact_dump,
211 .init = tcf_gact_init,
212 .walk = tcf_gact_walker,
213 .lookup = tcf_gact_search,
216 static __net_init int gact_init_net(struct net *net)
218 struct tc_action_net *tn = net_generic(net, gact_net_id);
220 return tc_action_net_init(tn, &act_gact_ops, GACT_TAB_MASK);
223 static void __net_exit gact_exit_net(struct net *net)
225 struct tc_action_net *tn = net_generic(net, gact_net_id);
227 tc_action_net_exit(tn);
230 static struct pernet_operations gact_net_ops = {
231 .init = gact_init_net,
232 .exit = gact_exit_net,
234 .size = sizeof(struct tc_action_net),
237 MODULE_AUTHOR("Jamal Hadi Salim(2002-4)");
238 MODULE_DESCRIPTION("Generic Classifier actions");
239 MODULE_LICENSE("GPL");
241 static int __init gact_init_module(void)
243 #ifdef CONFIG_GACT_PROB
244 pr_info("GACT probability on\n");
246 pr_info("GACT probability NOT on\n");
249 return tcf_register_action(&act_gact_ops, &gact_net_ops);
252 static void __exit gact_cleanup_module(void)
254 tcf_unregister_action(&act_gact_ops, &gact_net_ops);
257 module_init(gact_init_module);
258 module_exit(gact_cleanup_module);