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/module.h>
20 #include <linux/rtnetlink.h>
21 #include <linux/init.h>
22 #include <net/act_api.h>
23 #include <net/netlink.h>
25 #define L2T(p,L) ((p)->tcfp_R_tab->data[(L)>>(p)->tcfp_R_tab->rate.cell_log])
26 #define L2T_P(p,L) ((p)->tcfp_P_tab->data[(L)>>(p)->tcfp_P_tab->rate.cell_log])
28 #define POL_TAB_MASK 15
29 static struct tcf_common *tcf_police_ht[POL_TAB_MASK + 1];
30 static u32 police_idx_gen;
31 static DEFINE_RWLOCK(police_lock);
33 static struct tcf_hashinfo police_hash_info = {
34 .htab = tcf_police_ht,
35 .hmask = POL_TAB_MASK,
39 /* old policer structure from before tc actions */
40 struct tc_police_compat
47 struct tc_ratespec rate;
48 struct tc_ratespec peakrate;
51 /* Each policer is serialized by its individual spinlock */
53 static int tcf_act_police_walker(struct sk_buff *skb, struct netlink_callback *cb,
54 int type, struct tc_action *a)
57 int err = 0, index = -1, i = 0, s_i = 0, n_i = 0;
60 read_lock(&police_lock);
64 for (i = 0; i < (POL_TAB_MASK + 1); i++) {
65 p = tcf_police_ht[tcf_hash(i, POL_TAB_MASK)];
67 for (; p; p = p->tcfc_next) {
73 r = (struct rtattr *)skb_tail_pointer(skb);
74 RTA_PUT(skb, a->order, 0, NULL);
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);
84 r->rta_len = skb_tail_pointer(skb) - (u8 *)r;
89 read_unlock(&police_lock);
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 rtattr *rta, struct rtattr *est,
123 struct tc_action *a, int ovr, int bind)
127 struct rtattr *tb[TCA_POLICE_MAX];
128 struct tc_police *parm;
129 struct tcf_police *police;
130 struct qdisc_rate_table *R_tab = NULL, *P_tab = NULL;
133 if (rta == NULL || rtattr_parse_nested(tb, TCA_POLICE_MAX, rta) < 0)
136 if (tb[TCA_POLICE_TBF-1] == NULL)
138 size = RTA_PAYLOAD(tb[TCA_POLICE_TBF-1]);
139 if (size != sizeof(*parm) && size != sizeof(struct tc_police_compat))
141 parm = RTA_DATA(tb[TCA_POLICE_TBF-1]);
143 if (tb[TCA_POLICE_RESULT-1] != NULL &&
144 RTA_PAYLOAD(tb[TCA_POLICE_RESULT-1]) != sizeof(u32))
146 if (tb[TCA_POLICE_RESULT-1] != NULL &&
147 RTA_PAYLOAD(tb[TCA_POLICE_RESULT-1]) != sizeof(u32))
151 struct tcf_common *pc;
153 pc = tcf_hash_lookup(parm->index, &police_hash_info);
156 police = to_police(pc);
158 police->tcf_bindcnt += 1;
159 police->tcf_refcnt += 1;
167 police = kzalloc(sizeof(*police), GFP_KERNEL);
171 police->tcf_refcnt = 1;
172 spin_lock_init(&police->tcf_lock);
174 police->tcf_bindcnt = 1;
176 if (parm->rate.rate) {
178 R_tab = qdisc_get_rtab(&parm->rate, tb[TCA_POLICE_RATE-1]);
181 if (parm->peakrate.rate) {
182 P_tab = qdisc_get_rtab(&parm->peakrate,
183 tb[TCA_POLICE_PEAKRATE-1]);
185 qdisc_put_rtab(R_tab);
190 /* No failure allowed after this point */
191 spin_lock_bh(&police->tcf_lock);
193 qdisc_put_rtab(police->tcfp_R_tab);
194 police->tcfp_R_tab = R_tab;
197 qdisc_put_rtab(police->tcfp_P_tab);
198 police->tcfp_P_tab = P_tab;
201 if (tb[TCA_POLICE_RESULT-1])
202 police->tcfp_result = *(u32*)RTA_DATA(tb[TCA_POLICE_RESULT-1]);
203 police->tcfp_toks = police->tcfp_burst = parm->burst;
204 police->tcfp_mtu = parm->mtu;
205 if (police->tcfp_mtu == 0) {
206 police->tcfp_mtu = ~0;
207 if (police->tcfp_R_tab)
208 police->tcfp_mtu = 255<<police->tcfp_R_tab->rate.cell_log;
210 if (police->tcfp_P_tab)
211 police->tcfp_ptoks = L2T_P(police, police->tcfp_mtu);
212 police->tcf_action = parm->action;
214 if (tb[TCA_POLICE_AVRATE-1])
215 police->tcfp_ewma_rate =
216 *(u32*)RTA_DATA(tb[TCA_POLICE_AVRATE-1]);
218 gen_replace_estimator(&police->tcf_bstats,
219 &police->tcf_rate_est,
220 &police->tcf_lock, est);
222 spin_unlock_bh(&police->tcf_lock);
223 if (ret != ACT_P_CREATED)
226 police->tcfp_t_c = psched_get_time();
227 police->tcf_index = parm->index ? parm->index :
228 tcf_hash_new_index(&police_idx_gen, &police_hash_info);
229 h = tcf_hash(police->tcf_index, POL_TAB_MASK);
230 write_lock_bh(&police_lock);
231 police->tcf_next = tcf_police_ht[h];
232 tcf_police_ht[h] = &police->common;
233 write_unlock_bh(&police_lock);
239 if (ret == ACT_P_CREATED)
244 static int tcf_act_police_cleanup(struct tc_action *a, int bind)
246 struct tcf_police *p = a->priv;
254 if (p->tcf_refcnt <= 0 && !p->tcf_bindcnt) {
255 tcf_police_destroy(p);
262 static int tcf_act_police(struct sk_buff *skb, struct tc_action *a,
263 struct tcf_result *res)
265 struct tcf_police *police = a->priv;
270 spin_lock(&police->tcf_lock);
272 police->tcf_bstats.bytes += skb->len;
273 police->tcf_bstats.packets++;
275 if (police->tcfp_ewma_rate &&
276 police->tcf_rate_est.bps >= police->tcfp_ewma_rate) {
277 police->tcf_qstats.overlimits++;
278 spin_unlock(&police->tcf_lock);
279 return police->tcf_action;
282 if (skb->len <= police->tcfp_mtu) {
283 if (police->tcfp_R_tab == NULL) {
284 spin_unlock(&police->tcf_lock);
285 return police->tcfp_result;
288 now = psched_get_time();
289 toks = psched_tdiff_bounded(now, police->tcfp_t_c,
291 if (police->tcfp_P_tab) {
292 ptoks = toks + police->tcfp_ptoks;
293 if (ptoks > (long)L2T_P(police, police->tcfp_mtu))
294 ptoks = (long)L2T_P(police, police->tcfp_mtu);
295 ptoks -= L2T_P(police, skb->len);
297 toks += police->tcfp_toks;
298 if (toks > (long)police->tcfp_burst)
299 toks = police->tcfp_burst;
300 toks -= L2T(police, skb->len);
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 spin_unlock(&police->tcf_lock);
312 return police->tcf_action;
316 tcf_act_police_dump(struct sk_buff *skb, struct tc_action *a, int bind, int ref)
318 unsigned char *b = skb_tail_pointer(skb);
319 struct tcf_police *police = a->priv;
320 struct tc_police opt;
322 opt.index = police->tcf_index;
323 opt.action = police->tcf_action;
324 opt.mtu = police->tcfp_mtu;
325 opt.burst = police->tcfp_burst;
326 opt.refcnt = police->tcf_refcnt - ref;
327 opt.bindcnt = police->tcf_bindcnt - bind;
328 if (police->tcfp_R_tab)
329 opt.rate = police->tcfp_R_tab->rate;
331 memset(&opt.rate, 0, sizeof(opt.rate));
332 if (police->tcfp_P_tab)
333 opt.peakrate = police->tcfp_P_tab->rate;
335 memset(&opt.peakrate, 0, sizeof(opt.peakrate));
336 RTA_PUT(skb, TCA_POLICE_TBF, sizeof(opt), &opt);
337 if (police->tcfp_result)
338 RTA_PUT(skb, TCA_POLICE_RESULT, sizeof(int),
339 &police->tcfp_result);
340 if (police->tcfp_ewma_rate)
341 RTA_PUT(skb, TCA_POLICE_AVRATE, 4, &police->tcfp_ewma_rate);
349 MODULE_AUTHOR("Alexey Kuznetsov");
350 MODULE_DESCRIPTION("Policing actions");
351 MODULE_LICENSE("GPL");
353 static struct tc_action_ops act_police_ops = {
355 .hinfo = &police_hash_info,
356 .type = TCA_ID_POLICE,
357 .capab = TCA_CAP_NONE,
358 .owner = THIS_MODULE,
359 .act = tcf_act_police,
360 .dump = tcf_act_police_dump,
361 .cleanup = tcf_act_police_cleanup,
362 .lookup = tcf_hash_search,
363 .init = tcf_act_police_locate,
364 .walk = tcf_act_police_walker
368 police_init_module(void)
370 return tcf_register_action(&act_police_ops);
374 police_cleanup_module(void)
376 tcf_unregister_action(&act_police_ops);
379 module_init(police_init_module);
380 module_exit(police_cleanup_module);