2 * net/sched/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 <net/act_api.h>
22 #include <net/netlink.h>
24 #define L2T(p,L) qdisc_l2t((p)->tcfp_R_tab, L)
25 #define L2T_P(p,L) qdisc_l2t((p)->tcfp_P_tab, L)
27 #define POL_TAB_MASK 15
28 static struct tcf_common *tcf_police_ht[POL_TAB_MASK + 1];
29 static u32 police_idx_gen;
30 static DEFINE_RWLOCK(police_lock);
32 static struct tcf_hashinfo police_hash_info = {
33 .htab = tcf_police_ht,
34 .hmask = POL_TAB_MASK,
38 /* old policer structure from before tc actions */
39 struct tc_police_compat
46 struct tc_ratespec rate;
47 struct tc_ratespec peakrate;
50 /* Each policer is serialized by its individual spinlock */
52 static int tcf_act_police_walker(struct sk_buff *skb, struct netlink_callback *cb,
53 int type, struct tc_action *a)
56 int err = 0, index = -1, i = 0, s_i = 0, n_i = 0;
59 read_lock_bh(&police_lock);
63 for (i = 0; i < (POL_TAB_MASK + 1); i++) {
64 p = tcf_police_ht[tcf_hash(i, POL_TAB_MASK)];
66 for (; p; p = p->tcfc_next) {
72 nest = nla_nest_start(skb, a->order);
75 if (type == RTM_DELACTION)
76 err = tcf_action_dump_1(skb, a, 0, 1);
78 err = tcf_action_dump_1(skb, a, 0, 0);
81 nla_nest_cancel(skb, nest);
84 nla_nest_end(skb, nest);
89 read_unlock_bh(&police_lock);
95 nla_nest_cancel(skb, nest);
99 static void tcf_police_destroy(struct tcf_police *p)
101 unsigned int h = tcf_hash(p->tcf_index, POL_TAB_MASK);
102 struct tcf_common **p1p;
104 for (p1p = &tcf_police_ht[h]; *p1p; p1p = &(*p1p)->tcfc_next) {
105 if (*p1p == &p->common) {
106 write_lock_bh(&police_lock);
108 write_unlock_bh(&police_lock);
109 gen_kill_estimator(&p->tcf_bstats,
112 qdisc_put_rtab(p->tcfp_R_tab);
114 qdisc_put_rtab(p->tcfp_P_tab);
122 static int tcf_act_police_locate(struct nlattr *nla, struct nlattr *est,
123 struct tc_action *a, int ovr, int bind)
127 struct nlattr *tb[TCA_POLICE_MAX + 1];
128 struct tc_police *parm;
129 struct tcf_police *police;
130 struct qdisc_rate_table *R_tab = NULL, *P_tab = NULL;
136 err = nla_parse_nested(tb, TCA_POLICE_MAX, nla, NULL);
140 if (tb[TCA_POLICE_TBF] == NULL)
142 size = nla_len(tb[TCA_POLICE_TBF]);
143 if (size != sizeof(*parm) && size != sizeof(struct tc_police_compat))
145 parm = nla_data(tb[TCA_POLICE_TBF]);
147 if (tb[TCA_POLICE_RESULT] != NULL &&
148 nla_len(tb[TCA_POLICE_RESULT]) != sizeof(u32))
150 if (tb[TCA_POLICE_RESULT] != NULL &&
151 nla_len(tb[TCA_POLICE_RESULT]) != sizeof(u32))
155 struct tcf_common *pc;
157 pc = tcf_hash_lookup(parm->index, &police_hash_info);
160 police = to_police(pc);
162 police->tcf_bindcnt += 1;
163 police->tcf_refcnt += 1;
171 police = kzalloc(sizeof(*police), GFP_KERNEL);
175 police->tcf_refcnt = 1;
176 spin_lock_init(&police->tcf_lock);
178 police->tcf_bindcnt = 1;
180 if (parm->rate.rate) {
182 R_tab = qdisc_get_rtab(&parm->rate, tb[TCA_POLICE_RATE]);
185 if (parm->peakrate.rate) {
186 P_tab = qdisc_get_rtab(&parm->peakrate,
187 tb[TCA_POLICE_PEAKRATE]);
189 qdisc_put_rtab(R_tab);
194 /* No failure allowed after this point */
195 spin_lock_bh(&police->tcf_lock);
197 qdisc_put_rtab(police->tcfp_R_tab);
198 police->tcfp_R_tab = R_tab;
201 qdisc_put_rtab(police->tcfp_P_tab);
202 police->tcfp_P_tab = P_tab;
205 if (tb[TCA_POLICE_RESULT])
206 police->tcfp_result = *(u32*)nla_data(tb[TCA_POLICE_RESULT]);
207 police->tcfp_toks = police->tcfp_burst = parm->burst;
208 police->tcfp_mtu = parm->mtu;
209 if (police->tcfp_mtu == 0) {
210 police->tcfp_mtu = ~0;
211 if (police->tcfp_R_tab)
212 police->tcfp_mtu = 255<<police->tcfp_R_tab->rate.cell_log;
214 if (police->tcfp_P_tab)
215 police->tcfp_ptoks = L2T_P(police, police->tcfp_mtu);
216 police->tcf_action = parm->action;
218 if (tb[TCA_POLICE_AVRATE])
219 police->tcfp_ewma_rate =
220 *(u32*)nla_data(tb[TCA_POLICE_AVRATE]);
222 gen_replace_estimator(&police->tcf_bstats,
223 &police->tcf_rate_est,
224 &police->tcf_lock, est);
226 spin_unlock_bh(&police->tcf_lock);
227 if (ret != ACT_P_CREATED)
230 police->tcfp_t_c = psched_get_time();
231 police->tcf_index = parm->index ? parm->index :
232 tcf_hash_new_index(&police_idx_gen, &police_hash_info);
233 h = tcf_hash(police->tcf_index, POL_TAB_MASK);
234 write_lock_bh(&police_lock);
235 police->tcf_next = tcf_police_ht[h];
236 tcf_police_ht[h] = &police->common;
237 write_unlock_bh(&police_lock);
243 if (ret == ACT_P_CREATED)
248 static int tcf_act_police_cleanup(struct tc_action *a, int bind)
250 struct tcf_police *p = a->priv;
258 if (p->tcf_refcnt <= 0 && !p->tcf_bindcnt) {
259 tcf_police_destroy(p);
266 static int tcf_act_police(struct sk_buff *skb, struct tc_action *a,
267 struct tcf_result *res)
269 struct tcf_police *police = a->priv;
274 spin_lock(&police->tcf_lock);
276 police->tcf_bstats.bytes += skb->len;
277 police->tcf_bstats.packets++;
279 if (police->tcfp_ewma_rate &&
280 police->tcf_rate_est.bps >= police->tcfp_ewma_rate) {
281 police->tcf_qstats.overlimits++;
282 spin_unlock(&police->tcf_lock);
283 return police->tcf_action;
286 if (skb->len <= police->tcfp_mtu) {
287 if (police->tcfp_R_tab == NULL) {
288 spin_unlock(&police->tcf_lock);
289 return police->tcfp_result;
292 now = psched_get_time();
293 toks = psched_tdiff_bounded(now, police->tcfp_t_c,
295 if (police->tcfp_P_tab) {
296 ptoks = toks + police->tcfp_ptoks;
297 if (ptoks > (long)L2T_P(police, police->tcfp_mtu))
298 ptoks = (long)L2T_P(police, police->tcfp_mtu);
299 ptoks -= L2T_P(police, skb->len);
301 toks += police->tcfp_toks;
302 if (toks > (long)police->tcfp_burst)
303 toks = police->tcfp_burst;
304 toks -= L2T(police, skb->len);
305 if ((toks|ptoks) >= 0) {
306 police->tcfp_t_c = now;
307 police->tcfp_toks = toks;
308 police->tcfp_ptoks = ptoks;
309 spin_unlock(&police->tcf_lock);
310 return police->tcfp_result;
314 police->tcf_qstats.overlimits++;
315 spin_unlock(&police->tcf_lock);
316 return police->tcf_action;
320 tcf_act_police_dump(struct sk_buff *skb, struct tc_action *a, int bind, int ref)
322 unsigned char *b = skb_tail_pointer(skb);
323 struct tcf_police *police = a->priv;
324 struct tc_police opt;
326 opt.index = police->tcf_index;
327 opt.action = police->tcf_action;
328 opt.mtu = police->tcfp_mtu;
329 opt.burst = police->tcfp_burst;
330 opt.refcnt = police->tcf_refcnt - ref;
331 opt.bindcnt = police->tcf_bindcnt - bind;
332 if (police->tcfp_R_tab)
333 opt.rate = police->tcfp_R_tab->rate;
335 memset(&opt.rate, 0, sizeof(opt.rate));
336 if (police->tcfp_P_tab)
337 opt.peakrate = police->tcfp_P_tab->rate;
339 memset(&opt.peakrate, 0, sizeof(opt.peakrate));
340 NLA_PUT(skb, TCA_POLICE_TBF, sizeof(opt), &opt);
341 if (police->tcfp_result)
342 NLA_PUT(skb, TCA_POLICE_RESULT, sizeof(int),
343 &police->tcfp_result);
344 if (police->tcfp_ewma_rate)
345 NLA_PUT(skb, TCA_POLICE_AVRATE, 4, &police->tcfp_ewma_rate);
353 MODULE_AUTHOR("Alexey Kuznetsov");
354 MODULE_DESCRIPTION("Policing actions");
355 MODULE_LICENSE("GPL");
357 static struct tc_action_ops act_police_ops = {
359 .hinfo = &police_hash_info,
360 .type = TCA_ID_POLICE,
361 .capab = TCA_CAP_NONE,
362 .owner = THIS_MODULE,
363 .act = tcf_act_police,
364 .dump = tcf_act_police_dump,
365 .cleanup = tcf_act_police_cleanup,
366 .lookup = tcf_hash_search,
367 .init = tcf_act_police_locate,
368 .walk = tcf_act_police_walker
372 police_init_module(void)
374 return tcf_register_action(&act_police_ops);
378 police_cleanup_module(void)
380 tcf_unregister_action(&act_police_ops);
383 module_init(police_init_module);
384 module_exit(police_cleanup_module);