1 // SPDX-License-Identifier: GPL-2.0-or-later
3 * net/sched/act_police.c Input police filter
5 * Authors: Alexey Kuznetsov, <kuznet@ms2.inr.ac.ru>
6 * J Hadi Salim (action changes)
9 #include <linux/module.h>
10 #include <linux/types.h>
11 #include <linux/kernel.h>
12 #include <linux/string.h>
13 #include <linux/errno.h>
14 #include <linux/skbuff.h>
15 #include <linux/rtnetlink.h>
16 #include <linux/init.h>
17 #include <linux/slab.h>
18 #include <net/act_api.h>
19 #include <net/netlink.h>
20 #include <net/pkt_cls.h>
21 #include <net/tc_act/tc_police.h>
23 /* Each policer is serialized by its individual spinlock */
25 static unsigned int police_net_id;
26 static struct tc_action_ops act_police_ops;
28 static int tcf_police_walker(struct net *net, struct sk_buff *skb,
29 struct netlink_callback *cb, int type,
30 const struct tc_action_ops *ops,
31 struct netlink_ext_ack *extack)
33 struct tc_action_net *tn = net_generic(net, police_net_id);
35 return tcf_generic_walker(tn, skb, cb, type, ops, extack);
38 static const struct nla_policy police_policy[TCA_POLICE_MAX + 1] = {
39 [TCA_POLICE_RATE] = { .len = TC_RTAB_SIZE },
40 [TCA_POLICE_PEAKRATE] = { .len = TC_RTAB_SIZE },
41 [TCA_POLICE_AVRATE] = { .type = NLA_U32 },
42 [TCA_POLICE_RESULT] = { .type = NLA_U32 },
43 [TCA_POLICE_RATE64] = { .type = NLA_U64 },
44 [TCA_POLICE_PEAKRATE64] = { .type = NLA_U64 },
47 static int tcf_police_init(struct net *net, struct nlattr *nla,
48 struct nlattr *est, struct tc_action **a,
49 int ovr, int bind, bool rtnl_held,
50 struct tcf_proto *tp, u32 flags,
51 struct netlink_ext_ack *extack)
53 int ret = 0, tcfp_result = TC_ACT_OK, err, size;
54 struct nlattr *tb[TCA_POLICE_MAX + 1];
55 struct tcf_chain *goto_ch = NULL;
56 struct tc_police *parm;
57 struct tcf_police *police;
58 struct qdisc_rate_table *R_tab = NULL, *P_tab = NULL;
59 struct tc_action_net *tn = net_generic(net, police_net_id);
60 struct tcf_police_params *new;
68 err = nla_parse_nested_deprecated(tb, TCA_POLICE_MAX, nla,
73 if (tb[TCA_POLICE_TBF] == NULL)
75 size = nla_len(tb[TCA_POLICE_TBF]);
76 if (size != sizeof(*parm) && size != sizeof(struct tc_police_compat))
79 parm = nla_data(tb[TCA_POLICE_TBF]);
81 err = tcf_idr_check_alloc(tn, &index, a, bind);
89 ret = tcf_idr_create(tn, index, NULL, a,
90 &act_police_ops, bind, true, 0);
92 tcf_idr_cleanup(tn, index);
96 spin_lock_init(&(to_police(*a)->tcfp_lock));
98 tcf_idr_release(*a, bind);
101 err = tcf_action_check_ctrlact(parm->action, tp, &goto_ch, extack);
105 police = to_police(*a);
106 if (parm->rate.rate) {
108 R_tab = qdisc_get_rtab(&parm->rate, tb[TCA_POLICE_RATE], NULL);
112 if (parm->peakrate.rate) {
113 P_tab = qdisc_get_rtab(&parm->peakrate,
114 tb[TCA_POLICE_PEAKRATE], NULL);
121 err = gen_replace_estimator(&police->tcf_bstats,
122 police->common.cpu_bstats,
123 &police->tcf_rate_est,
128 } else if (tb[TCA_POLICE_AVRATE] &&
129 (ret == ACT_P_CREATED ||
130 !gen_estimator_active(&police->tcf_rate_est))) {
135 if (tb[TCA_POLICE_RESULT]) {
136 tcfp_result = nla_get_u32(tb[TCA_POLICE_RESULT]);
137 if (TC_ACT_EXT_CMP(tcfp_result, TC_ACT_GOTO_CHAIN)) {
138 NL_SET_ERR_MSG(extack,
139 "goto chain not allowed on fallback");
145 new = kzalloc(sizeof(*new), GFP_KERNEL);
146 if (unlikely(!new)) {
151 /* No failure allowed after this point */
152 new->tcfp_result = tcfp_result;
153 new->tcfp_mtu = parm->mtu;
154 if (!new->tcfp_mtu) {
157 new->tcfp_mtu = 255 << R_tab->rate.cell_log;
160 new->rate_present = true;
161 rate64 = tb[TCA_POLICE_RATE64] ?
162 nla_get_u64(tb[TCA_POLICE_RATE64]) : 0;
163 psched_ratecfg_precompute(&new->rate, &R_tab->rate, rate64);
164 qdisc_put_rtab(R_tab);
166 new->rate_present = false;
169 new->peak_present = true;
170 prate64 = tb[TCA_POLICE_PEAKRATE64] ?
171 nla_get_u64(tb[TCA_POLICE_PEAKRATE64]) : 0;
172 psched_ratecfg_precompute(&new->peak, &P_tab->rate, prate64);
173 qdisc_put_rtab(P_tab);
175 new->peak_present = false;
178 new->tcfp_burst = PSCHED_TICKS2NS(parm->burst);
179 if (new->peak_present)
180 new->tcfp_mtu_ptoks = (s64)psched_l2t_ns(&new->peak,
183 if (tb[TCA_POLICE_AVRATE])
184 new->tcfp_ewma_rate = nla_get_u32(tb[TCA_POLICE_AVRATE]);
186 spin_lock_bh(&police->tcf_lock);
187 spin_lock_bh(&police->tcfp_lock);
188 police->tcfp_t_c = ktime_get_ns();
189 police->tcfp_toks = new->tcfp_burst;
190 if (new->peak_present)
191 police->tcfp_ptoks = new->tcfp_mtu_ptoks;
192 spin_unlock_bh(&police->tcfp_lock);
193 goto_ch = tcf_action_set_ctrlact(*a, parm->action, goto_ch);
194 new = rcu_replace_pointer(police->params,
196 lockdep_is_held(&police->tcf_lock));
197 spin_unlock_bh(&police->tcf_lock);
200 tcf_chain_put_by_act(goto_ch);
207 qdisc_put_rtab(P_tab);
208 qdisc_put_rtab(R_tab);
210 tcf_chain_put_by_act(goto_ch);
212 tcf_idr_release(*a, bind);
216 static int tcf_police_act(struct sk_buff *skb, const struct tc_action *a,
217 struct tcf_result *res)
219 struct tcf_police *police = to_police(a);
220 struct tcf_police_params *p;
221 s64 now, toks, ptoks = 0;
224 tcf_lastuse_update(&police->tcf_tm);
225 bstats_cpu_update(this_cpu_ptr(police->common.cpu_bstats), skb);
227 ret = READ_ONCE(police->tcf_action);
228 p = rcu_dereference_bh(police->params);
230 if (p->tcfp_ewma_rate) {
231 struct gnet_stats_rate_est64 sample;
233 if (!gen_estimator_read(&police->tcf_rate_est, &sample) ||
234 sample.bps >= p->tcfp_ewma_rate)
238 if (qdisc_pkt_len(skb) <= p->tcfp_mtu) {
239 if (!p->rate_present) {
240 ret = p->tcfp_result;
244 now = ktime_get_ns();
245 spin_lock_bh(&police->tcfp_lock);
246 toks = min_t(s64, now - police->tcfp_t_c, p->tcfp_burst);
247 if (p->peak_present) {
248 ptoks = toks + police->tcfp_ptoks;
249 if (ptoks > p->tcfp_mtu_ptoks)
250 ptoks = p->tcfp_mtu_ptoks;
251 ptoks -= (s64)psched_l2t_ns(&p->peak,
254 toks += police->tcfp_toks;
255 if (toks > p->tcfp_burst)
256 toks = p->tcfp_burst;
257 toks -= (s64)psched_l2t_ns(&p->rate, qdisc_pkt_len(skb));
258 if ((toks|ptoks) >= 0) {
259 police->tcfp_t_c = now;
260 police->tcfp_toks = toks;
261 police->tcfp_ptoks = ptoks;
262 spin_unlock_bh(&police->tcfp_lock);
263 ret = p->tcfp_result;
266 spin_unlock_bh(&police->tcfp_lock);
270 qstats_overlimit_inc(this_cpu_ptr(police->common.cpu_qstats));
272 if (ret == TC_ACT_SHOT)
273 qstats_drop_inc(this_cpu_ptr(police->common.cpu_qstats));
278 static void tcf_police_cleanup(struct tc_action *a)
280 struct tcf_police *police = to_police(a);
281 struct tcf_police_params *p;
283 p = rcu_dereference_protected(police->params, 1);
288 static void tcf_police_stats_update(struct tc_action *a,
289 u64 bytes, u64 packets, u64 drops,
290 u64 lastuse, bool hw)
292 struct tcf_police *police = to_police(a);
293 struct tcf_t *tm = &police->tcf_tm;
295 tcf_action_update_stats(a, bytes, packets, drops, hw);
296 tm->lastuse = max_t(u64, tm->lastuse, lastuse);
299 static int tcf_police_dump(struct sk_buff *skb, struct tc_action *a,
302 unsigned char *b = skb_tail_pointer(skb);
303 struct tcf_police *police = to_police(a);
304 struct tcf_police_params *p;
305 struct tc_police opt = {
306 .index = police->tcf_index,
307 .refcnt = refcount_read(&police->tcf_refcnt) - ref,
308 .bindcnt = atomic_read(&police->tcf_bindcnt) - bind,
312 spin_lock_bh(&police->tcf_lock);
313 opt.action = police->tcf_action;
314 p = rcu_dereference_protected(police->params,
315 lockdep_is_held(&police->tcf_lock));
316 opt.mtu = p->tcfp_mtu;
317 opt.burst = PSCHED_NS2TICKS(p->tcfp_burst);
318 if (p->rate_present) {
319 psched_ratecfg_getrate(&opt.rate, &p->rate);
320 if ((police->params->rate.rate_bytes_ps >= (1ULL << 32)) &&
321 nla_put_u64_64bit(skb, TCA_POLICE_RATE64,
322 police->params->rate.rate_bytes_ps,
324 goto nla_put_failure;
326 if (p->peak_present) {
327 psched_ratecfg_getrate(&opt.peakrate, &p->peak);
328 if ((police->params->peak.rate_bytes_ps >= (1ULL << 32)) &&
329 nla_put_u64_64bit(skb, TCA_POLICE_PEAKRATE64,
330 police->params->peak.rate_bytes_ps,
332 goto nla_put_failure;
334 if (nla_put(skb, TCA_POLICE_TBF, sizeof(opt), &opt))
335 goto nla_put_failure;
336 if (p->tcfp_result &&
337 nla_put_u32(skb, TCA_POLICE_RESULT, p->tcfp_result))
338 goto nla_put_failure;
339 if (p->tcfp_ewma_rate &&
340 nla_put_u32(skb, TCA_POLICE_AVRATE, p->tcfp_ewma_rate))
341 goto nla_put_failure;
343 tcf_tm_dump(&t, &police->tcf_tm);
344 if (nla_put_64bit(skb, TCA_POLICE_TM, sizeof(t), &t, TCA_POLICE_PAD))
345 goto nla_put_failure;
346 spin_unlock_bh(&police->tcf_lock);
351 spin_unlock_bh(&police->tcf_lock);
356 static int tcf_police_search(struct net *net, struct tc_action **a, u32 index)
358 struct tc_action_net *tn = net_generic(net, police_net_id);
360 return tcf_idr_search(tn, a, index);
363 MODULE_AUTHOR("Alexey Kuznetsov");
364 MODULE_DESCRIPTION("Policing actions");
365 MODULE_LICENSE("GPL");
367 static struct tc_action_ops act_police_ops = {
370 .owner = THIS_MODULE,
371 .stats_update = tcf_police_stats_update,
372 .act = tcf_police_act,
373 .dump = tcf_police_dump,
374 .init = tcf_police_init,
375 .walk = tcf_police_walker,
376 .lookup = tcf_police_search,
377 .cleanup = tcf_police_cleanup,
378 .size = sizeof(struct tcf_police),
381 static __net_init int police_init_net(struct net *net)
383 struct tc_action_net *tn = net_generic(net, police_net_id);
385 return tc_action_net_init(net, tn, &act_police_ops);
388 static void __net_exit police_exit_net(struct list_head *net_list)
390 tc_action_net_exit(net_list, police_net_id);
393 static struct pernet_operations police_net_ops = {
394 .init = police_init_net,
395 .exit_batch = police_exit_net,
396 .id = &police_net_id,
397 .size = sizeof(struct tc_action_net),
400 static int __init police_init_module(void)
402 return tcf_register_action(&act_police_ops, &police_net_ops);
405 static void __exit police_cleanup_module(void)
407 tcf_unregister_action(&act_police_ops, &police_net_ops);
410 module_init(police_init_module);
411 module_exit(police_cleanup_module);