2 * net/sched/act_police.c Input police filter
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 * Authors: Alexey Kuznetsov, <kuznet@ms2.inr.ac.ru>
10 * J Hadi Salim (action changes)
13 #include <linux/module.h>
14 #include <linux/types.h>
15 #include <linux/kernel.h>
16 #include <linux/string.h>
17 #include <linux/errno.h>
18 #include <linux/skbuff.h>
19 #include <linux/rtnetlink.h>
20 #include <linux/init.h>
21 #include <linux/slab.h>
22 #include <net/act_api.h>
23 #include <net/netlink.h>
26 struct tcf_common common;
35 struct psched_ratecfg rate;
37 struct psched_ratecfg peak;
40 #define to_police(pc) \
41 container_of(pc, struct tcf_police, common)
43 #define POL_TAB_MASK 15
45 /* old policer structure from before tc actions */
46 struct tc_police_compat {
52 struct tc_ratespec rate;
53 struct tc_ratespec peakrate;
56 /* Each policer is serialized by its individual spinlock */
58 static int police_net_id;
60 static int tcf_act_police_walker(struct net *net, struct sk_buff *skb,
61 struct netlink_callback *cb, int type,
64 struct tc_action_net *tn = net_generic(net, police_net_id);
65 struct tcf_hashinfo *hinfo = tn->hinfo;
66 struct hlist_head *head;
68 int err = 0, index = -1, i = 0, s_i = 0, n_i = 0;
71 spin_lock_bh(&hinfo->lock);
75 for (i = 0; i < (POL_TAB_MASK + 1); i++) {
76 head = &hinfo->htab[tcf_hash(i, POL_TAB_MASK)];
78 hlist_for_each_entry_rcu(p, head, tcfc_head) {
84 nest = nla_nest_start(skb, a->order);
87 if (type == RTM_DELACTION)
88 err = tcf_action_dump_1(skb, a, 0, 1);
90 err = tcf_action_dump_1(skb, a, 0, 0);
93 nla_nest_cancel(skb, nest);
96 nla_nest_end(skb, nest);
101 spin_unlock_bh(&hinfo->lock);
107 nla_nest_cancel(skb, nest);
111 static const struct nla_policy police_policy[TCA_POLICE_MAX + 1] = {
112 [TCA_POLICE_RATE] = { .len = TC_RTAB_SIZE },
113 [TCA_POLICE_PEAKRATE] = { .len = TC_RTAB_SIZE },
114 [TCA_POLICE_AVRATE] = { .type = NLA_U32 },
115 [TCA_POLICE_RESULT] = { .type = NLA_U32 },
118 static int tcf_act_police_locate(struct net *net, struct nlattr *nla,
119 struct nlattr *est, struct tc_action *a,
124 struct nlattr *tb[TCA_POLICE_MAX + 1];
125 struct tc_police *parm;
126 struct tcf_police *police;
127 struct qdisc_rate_table *R_tab = NULL, *P_tab = NULL;
128 struct tc_action_net *tn = net_generic(net, police_net_id);
129 struct tcf_hashinfo *hinfo = tn->hinfo;
135 err = nla_parse_nested(tb, TCA_POLICE_MAX, nla, police_policy);
139 if (tb[TCA_POLICE_TBF] == NULL)
141 size = nla_len(tb[TCA_POLICE_TBF]);
142 if (size != sizeof(*parm) && size != sizeof(struct tc_police_compat))
144 parm = nla_data(tb[TCA_POLICE_TBF]);
147 if (tcf_hash_search(tn, a, parm->index)) {
148 police = to_police(a->priv);
150 police->tcf_bindcnt += 1;
151 police->tcf_refcnt += 1;
161 police = kzalloc(sizeof(*police), GFP_KERNEL);
165 police->tcf_refcnt = 1;
166 spin_lock_init(&police->tcf_lock);
168 police->tcf_bindcnt = 1;
170 if (parm->rate.rate) {
172 R_tab = qdisc_get_rtab(&parm->rate, tb[TCA_POLICE_RATE]);
176 if (parm->peakrate.rate) {
177 P_tab = qdisc_get_rtab(&parm->peakrate,
178 tb[TCA_POLICE_PEAKRATE]);
184 spin_lock_bh(&police->tcf_lock);
186 err = gen_replace_estimator(&police->tcf_bstats, NULL,
187 &police->tcf_rate_est,
188 &police->tcf_lock, est);
191 } else if (tb[TCA_POLICE_AVRATE] &&
192 (ret == ACT_P_CREATED ||
193 !gen_estimator_active(&police->tcf_bstats,
194 &police->tcf_rate_est))) {
199 /* No failure allowed after this point */
200 police->tcfp_mtu = parm->mtu;
201 if (police->tcfp_mtu == 0) {
202 police->tcfp_mtu = ~0;
204 police->tcfp_mtu = 255 << R_tab->rate.cell_log;
207 police->rate_present = true;
208 psched_ratecfg_precompute(&police->rate, &R_tab->rate, 0);
209 qdisc_put_rtab(R_tab);
211 police->rate_present = false;
214 police->peak_present = true;
215 psched_ratecfg_precompute(&police->peak, &P_tab->rate, 0);
216 qdisc_put_rtab(P_tab);
218 police->peak_present = false;
221 if (tb[TCA_POLICE_RESULT])
222 police->tcfp_result = nla_get_u32(tb[TCA_POLICE_RESULT]);
223 police->tcfp_burst = PSCHED_TICKS2NS(parm->burst);
224 police->tcfp_toks = police->tcfp_burst;
225 if (police->peak_present) {
226 police->tcfp_mtu_ptoks = (s64) psched_l2t_ns(&police->peak,
228 police->tcfp_ptoks = police->tcfp_mtu_ptoks;
230 police->tcf_action = parm->action;
232 if (tb[TCA_POLICE_AVRATE])
233 police->tcfp_ewma_rate = nla_get_u32(tb[TCA_POLICE_AVRATE]);
235 spin_unlock_bh(&police->tcf_lock);
236 if (ret != ACT_P_CREATED)
239 police->tcfp_t_c = ktime_get_ns();
240 police->tcf_index = parm->index ? parm->index :
241 tcf_hash_new_index(tn);
242 h = tcf_hash(police->tcf_index, POL_TAB_MASK);
243 spin_lock_bh(&hinfo->lock);
244 hlist_add_head(&police->tcf_head, &hinfo->htab[h]);
245 spin_unlock_bh(&hinfo->lock);
251 spin_unlock_bh(&police->tcf_lock);
253 qdisc_put_rtab(P_tab);
254 qdisc_put_rtab(R_tab);
255 if (ret == ACT_P_CREATED)
260 static int tcf_act_police(struct sk_buff *skb, const struct tc_action *a,
261 struct tcf_result *res)
263 struct tcf_police *police = a->priv;
268 spin_lock(&police->tcf_lock);
270 bstats_update(&police->tcf_bstats, skb);
272 if (police->tcfp_ewma_rate &&
273 police->tcf_rate_est.bps >= police->tcfp_ewma_rate) {
274 police->tcf_qstats.overlimits++;
275 if (police->tcf_action == TC_ACT_SHOT)
276 police->tcf_qstats.drops++;
277 spin_unlock(&police->tcf_lock);
278 return police->tcf_action;
281 if (qdisc_pkt_len(skb) <= police->tcfp_mtu) {
282 if (!police->rate_present) {
283 spin_unlock(&police->tcf_lock);
284 return police->tcfp_result;
287 now = ktime_get_ns();
288 toks = min_t(s64, now - police->tcfp_t_c,
290 if (police->peak_present) {
291 ptoks = toks + police->tcfp_ptoks;
292 if (ptoks > police->tcfp_mtu_ptoks)
293 ptoks = police->tcfp_mtu_ptoks;
294 ptoks -= (s64) psched_l2t_ns(&police->peak,
297 toks += police->tcfp_toks;
298 if (toks > police->tcfp_burst)
299 toks = police->tcfp_burst;
300 toks -= (s64) psched_l2t_ns(&police->rate, qdisc_pkt_len(skb));
301 if ((toks|ptoks) >= 0) {
302 police->tcfp_t_c = now;
303 police->tcfp_toks = toks;
304 police->tcfp_ptoks = ptoks;
305 spin_unlock(&police->tcf_lock);
306 return police->tcfp_result;
310 police->tcf_qstats.overlimits++;
311 if (police->tcf_action == TC_ACT_SHOT)
312 police->tcf_qstats.drops++;
313 spin_unlock(&police->tcf_lock);
314 return police->tcf_action;
318 tcf_act_police_dump(struct sk_buff *skb, struct tc_action *a, int bind, int ref)
320 unsigned char *b = skb_tail_pointer(skb);
321 struct tcf_police *police = a->priv;
322 struct tc_police opt = {
323 .index = police->tcf_index,
324 .action = police->tcf_action,
325 .mtu = police->tcfp_mtu,
326 .burst = PSCHED_NS2TICKS(police->tcfp_burst),
327 .refcnt = police->tcf_refcnt - ref,
328 .bindcnt = police->tcf_bindcnt - bind,
331 if (police->rate_present)
332 psched_ratecfg_getrate(&opt.rate, &police->rate);
333 if (police->peak_present)
334 psched_ratecfg_getrate(&opt.peakrate, &police->peak);
335 if (nla_put(skb, TCA_POLICE_TBF, sizeof(opt), &opt))
336 goto nla_put_failure;
337 if (police->tcfp_result &&
338 nla_put_u32(skb, TCA_POLICE_RESULT, police->tcfp_result))
339 goto nla_put_failure;
340 if (police->tcfp_ewma_rate &&
341 nla_put_u32(skb, TCA_POLICE_AVRATE, police->tcfp_ewma_rate))
342 goto nla_put_failure;
350 static int tcf_police_search(struct net *net, struct tc_action *a, u32 index)
352 struct tc_action_net *tn = net_generic(net, police_net_id);
354 return tcf_hash_search(tn, a, index);
357 MODULE_AUTHOR("Alexey Kuznetsov");
358 MODULE_DESCRIPTION("Policing actions");
359 MODULE_LICENSE("GPL");
361 static struct tc_action_ops act_police_ops = {
363 .type = TCA_ID_POLICE,
364 .owner = THIS_MODULE,
365 .act = tcf_act_police,
366 .dump = tcf_act_police_dump,
367 .init = tcf_act_police_locate,
368 .walk = tcf_act_police_walker,
369 .lookup = tcf_police_search,
372 static __net_init int police_init_net(struct net *net)
374 struct tc_action_net *tn = net_generic(net, police_net_id);
376 return tc_action_net_init(tn, &act_police_ops, POL_TAB_MASK);
379 static void __net_exit police_exit_net(struct net *net)
381 struct tc_action_net *tn = net_generic(net, police_net_id);
383 tc_action_net_exit(tn);
386 static struct pernet_operations police_net_ops = {
387 .init = police_init_net,
388 .exit = police_exit_net,
389 .id = &police_net_id,
390 .size = sizeof(struct tc_action_net),
394 police_init_module(void)
396 return tcf_register_action(&act_police_ops, &police_net_ops);
400 police_cleanup_module(void)
402 tcf_unregister_action(&act_police_ops, &police_net_ops);
405 module_init(police_init_module);
406 module_exit(police_cleanup_module);