Merge tag 'spi' of git://git.kernel.org/pub/scm/linux/kernel/git/arm/arm-soc
[GitHub/mt8127/android_kernel_alcatel_ttab.git] / net / sched / act_police.c
CommitLineData
1da177e4
LT
1/*
2 * net/sched/police.c Input police filter.
3 *
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.
8 *
9 * Authors: Alexey Kuznetsov, <kuznet@ms2.inr.ac.ru>
10 * J Hadi Salim (action changes)
11 */
12
1da177e4
LT
13#include <linux/module.h>
14#include <linux/types.h>
15#include <linux/kernel.h>
1da177e4 16#include <linux/string.h>
1da177e4 17#include <linux/errno.h>
1da177e4 18#include <linux/skbuff.h>
1da177e4
LT
19#include <linux/rtnetlink.h>
20#include <linux/init.h>
5a0e3ad6 21#include <linux/slab.h>
1da177e4 22#include <net/act_api.h>
dc5fc579 23#include <net/netlink.h>
1da177e4 24
cc7ec456
ED
25#define L2T(p, L) qdisc_l2t((p)->tcfp_R_tab, L)
26#define L2T_P(p, L) qdisc_l2t((p)->tcfp_P_tab, L)
1da177e4 27
e9ce1cd3
DM
28#define POL_TAB_MASK 15
29static struct tcf_common *tcf_police_ht[POL_TAB_MASK + 1];
30static u32 police_idx_gen;
31static DEFINE_RWLOCK(police_lock);
1da177e4 32
e9ce1cd3
DM
33static struct tcf_hashinfo police_hash_info = {
34 .htab = tcf_police_ht,
35 .hmask = POL_TAB_MASK,
36 .lock = &police_lock,
37};
1da177e4 38
1e9b3d53 39/* old policer structure from before tc actions */
cc7ec456 40struct tc_police_compat {
1e9b3d53
PM
41 u32 index;
42 int action;
43 u32 limit;
44 u32 burst;
45 u32 mtu;
46 struct tc_ratespec rate;
47 struct tc_ratespec peakrate;
48};
49
e9ce1cd3 50/* Each policer is serialized by its individual spinlock */
1da177e4 51
83b950c8 52static int tcf_act_police_walker(struct sk_buff *skb, struct netlink_callback *cb,
10297b99 53 int type, struct tc_action *a)
1da177e4 54{
e9ce1cd3 55 struct tcf_common *p;
1da177e4 56 int err = 0, index = -1, i = 0, s_i = 0, n_i = 0;
4b3550ef 57 struct nlattr *nest;
1da177e4 58
e1e992e5 59 read_lock_bh(&police_lock);
1da177e4
LT
60
61 s_i = cb->args[0];
62
e9ce1cd3
DM
63 for (i = 0; i < (POL_TAB_MASK + 1); i++) {
64 p = tcf_police_ht[tcf_hash(i, POL_TAB_MASK)];
1da177e4 65
e9ce1cd3 66 for (; p; p = p->tcfc_next) {
1da177e4
LT
67 index++;
68 if (index < s_i)
69 continue;
70 a->priv = p;
71 a->order = index;
4b3550ef
PM
72 nest = nla_nest_start(skb, a->order);
73 if (nest == NULL)
74 goto nla_put_failure;
1da177e4
LT
75 if (type == RTM_DELACTION)
76 err = tcf_action_dump_1(skb, a, 0, 1);
77 else
78 err = tcf_action_dump_1(skb, a, 0, 0);
79 if (err < 0) {
80 index--;
4b3550ef 81 nla_nest_cancel(skb, nest);
1da177e4
LT
82 goto done;
83 }
4b3550ef 84 nla_nest_end(skb, nest);
1da177e4
LT
85 n_i++;
86 }
87 }
88done:
e1e992e5 89 read_unlock_bh(&police_lock);
1da177e4
LT
90 if (n_i)
91 cb->args[0] += n_i;
92 return n_i;
93
7ba699c6 94nla_put_failure:
4b3550ef 95 nla_nest_cancel(skb, nest);
1da177e4
LT
96 goto done;
97}
1da177e4 98
c3bc7cff 99static void tcf_police_destroy(struct tcf_police *p)
1da177e4 100{
e9ce1cd3
DM
101 unsigned int h = tcf_hash(p->tcf_index, POL_TAB_MASK);
102 struct tcf_common **p1p;
10297b99 103
e9ce1cd3
DM
104 for (p1p = &tcf_police_ht[h]; *p1p; p1p = &(*p1p)->tcfc_next) {
105 if (*p1p == &p->common) {
1da177e4 106 write_lock_bh(&police_lock);
e9ce1cd3 107 *p1p = p->tcf_next;
1da177e4 108 write_unlock_bh(&police_lock);
e9ce1cd3
DM
109 gen_kill_estimator(&p->tcf_bstats,
110 &p->tcf_rate_est);
e9ce1cd3
DM
111 if (p->tcfp_R_tab)
112 qdisc_put_rtab(p->tcfp_R_tab);
113 if (p->tcfp_P_tab)
114 qdisc_put_rtab(p->tcfp_P_tab);
c7de2cf0
ED
115 /*
116 * gen_estimator est_timer() might access p->tcf_lock
117 * or bstats, wait a RCU grace period before freeing p
118 */
5957b1ac 119 kfree_rcu(p, tcf_rcu);
1da177e4
LT
120 return;
121 }
122 }
547b792c 123 WARN_ON(1);
1da177e4
LT
124}
125
53b2bf3f
PM
126static const struct nla_policy police_policy[TCA_POLICE_MAX + 1] = {
127 [TCA_POLICE_RATE] = { .len = TC_RTAB_SIZE },
128 [TCA_POLICE_PEAKRATE] = { .len = TC_RTAB_SIZE },
129 [TCA_POLICE_AVRATE] = { .type = NLA_U32 },
130 [TCA_POLICE_RESULT] = { .type = NLA_U32 },
131};
132
7ba699c6 133static int tcf_act_police_locate(struct nlattr *nla, struct nlattr *est,
10297b99 134 struct tc_action *a, int ovr, int bind)
1da177e4 135{
cc7ec456 136 unsigned int h;
1da177e4 137 int ret = 0, err;
7ba699c6 138 struct nlattr *tb[TCA_POLICE_MAX + 1];
1da177e4 139 struct tc_police *parm;
e9ce1cd3 140 struct tcf_police *police;
1da177e4 141 struct qdisc_rate_table *R_tab = NULL, *P_tab = NULL;
1e9b3d53 142 int size;
1da177e4 143
cee63723 144 if (nla == NULL)
1da177e4
LT
145 return -EINVAL;
146
53b2bf3f 147 err = nla_parse_nested(tb, TCA_POLICE_MAX, nla, police_policy);
cee63723
PM
148 if (err < 0)
149 return err;
150
7ba699c6 151 if (tb[TCA_POLICE_TBF] == NULL)
1e9b3d53 152 return -EINVAL;
7ba699c6 153 size = nla_len(tb[TCA_POLICE_TBF]);
1e9b3d53 154 if (size != sizeof(*parm) && size != sizeof(struct tc_police_compat))
1da177e4 155 return -EINVAL;
7ba699c6 156 parm = nla_data(tb[TCA_POLICE_TBF]);
1da177e4 157
e9ce1cd3
DM
158 if (parm->index) {
159 struct tcf_common *pc;
160
161 pc = tcf_hash_lookup(parm->index, &police_hash_info);
162 if (pc != NULL) {
163 a->priv = pc;
164 police = to_police(pc);
165 if (bind) {
166 police->tcf_bindcnt += 1;
167 police->tcf_refcnt += 1;
168 }
169 if (ovr)
170 goto override;
171 return ret;
1da177e4 172 }
1da177e4
LT
173 }
174
e9ce1cd3
DM
175 police = kzalloc(sizeof(*police), GFP_KERNEL);
176 if (police == NULL)
1da177e4 177 return -ENOMEM;
1da177e4 178 ret = ACT_P_CREATED;
e9ce1cd3
DM
179 police->tcf_refcnt = 1;
180 spin_lock_init(&police->tcf_lock);
1da177e4 181 if (bind)
e9ce1cd3 182 police->tcf_bindcnt = 1;
1da177e4
LT
183override:
184 if (parm->rate.rate) {
185 err = -ENOMEM;
7ba699c6 186 R_tab = qdisc_get_rtab(&parm->rate, tb[TCA_POLICE_RATE]);
1da177e4
LT
187 if (R_tab == NULL)
188 goto failure;
c1b56878 189
1da177e4
LT
190 if (parm->peakrate.rate) {
191 P_tab = qdisc_get_rtab(&parm->peakrate,
7ba699c6 192 tb[TCA_POLICE_PEAKRATE]);
71bcb09a 193 if (P_tab == NULL)
1da177e4 194 goto failure;
1da177e4
LT
195 }
196 }
71bcb09a 197
e9ce1cd3 198 spin_lock_bh(&police->tcf_lock);
71bcb09a
SH
199 if (est) {
200 err = gen_replace_estimator(&police->tcf_bstats,
201 &police->tcf_rate_est,
202 &police->tcf_lock, est);
203 if (err)
204 goto failure_unlock;
a883bf56
JP
205 } else if (tb[TCA_POLICE_AVRATE] &&
206 (ret == ACT_P_CREATED ||
207 !gen_estimator_active(&police->tcf_bstats,
208 &police->tcf_rate_est))) {
209 err = -EINVAL;
210 goto failure_unlock;
71bcb09a
SH
211 }
212
213 /* No failure allowed after this point */
1da177e4 214 if (R_tab != NULL) {
e9ce1cd3
DM
215 qdisc_put_rtab(police->tcfp_R_tab);
216 police->tcfp_R_tab = R_tab;
1da177e4
LT
217 }
218 if (P_tab != NULL) {
e9ce1cd3
DM
219 qdisc_put_rtab(police->tcfp_P_tab);
220 police->tcfp_P_tab = P_tab;
1da177e4
LT
221 }
222
7ba699c6 223 if (tb[TCA_POLICE_RESULT])
1587bac4 224 police->tcfp_result = nla_get_u32(tb[TCA_POLICE_RESULT]);
e9ce1cd3
DM
225 police->tcfp_toks = police->tcfp_burst = parm->burst;
226 police->tcfp_mtu = parm->mtu;
227 if (police->tcfp_mtu == 0) {
228 police->tcfp_mtu = ~0;
229 if (police->tcfp_R_tab)
230 police->tcfp_mtu = 255<<police->tcfp_R_tab->rate.cell_log;
1da177e4 231 }
e9ce1cd3
DM
232 if (police->tcfp_P_tab)
233 police->tcfp_ptoks = L2T_P(police, police->tcfp_mtu);
234 police->tcf_action = parm->action;
1da177e4 235
7ba699c6 236 if (tb[TCA_POLICE_AVRATE])
1587bac4 237 police->tcfp_ewma_rate = nla_get_u32(tb[TCA_POLICE_AVRATE]);
1da177e4 238
e9ce1cd3 239 spin_unlock_bh(&police->tcf_lock);
1da177e4
LT
240 if (ret != ACT_P_CREATED)
241 return ret;
242
3bebcda2 243 police->tcfp_t_c = psched_get_time();
e9ce1cd3
DM
244 police->tcf_index = parm->index ? parm->index :
245 tcf_hash_new_index(&police_idx_gen, &police_hash_info);
246 h = tcf_hash(police->tcf_index, POL_TAB_MASK);
1da177e4 247 write_lock_bh(&police_lock);
e9ce1cd3
DM
248 police->tcf_next = tcf_police_ht[h];
249 tcf_police_ht[h] = &police->common;
1da177e4
LT
250 write_unlock_bh(&police_lock);
251
e9ce1cd3 252 a->priv = police;
1da177e4
LT
253 return ret;
254
71bcb09a
SH
255failure_unlock:
256 spin_unlock_bh(&police->tcf_lock);
1da177e4 257failure:
71bcb09a
SH
258 if (P_tab)
259 qdisc_put_rtab(P_tab);
260 if (R_tab)
261 qdisc_put_rtab(R_tab);
1da177e4 262 if (ret == ACT_P_CREATED)
e9ce1cd3 263 kfree(police);
1da177e4
LT
264 return err;
265}
266
267static int tcf_act_police_cleanup(struct tc_action *a, int bind)
268{
e9ce1cd3 269 struct tcf_police *p = a->priv;
c3bc7cff 270 int ret = 0;
1da177e4 271
c3bc7cff
PM
272 if (p != NULL) {
273 if (bind)
274 p->tcf_bindcnt--;
275
276 p->tcf_refcnt--;
277 if (p->tcf_refcnt <= 0 && !p->tcf_bindcnt) {
278 tcf_police_destroy(p);
279 ret = 1;
280 }
281 }
282 return ret;
1da177e4
LT
283}
284
dc7f9f6e 285static int tcf_act_police(struct sk_buff *skb, const struct tc_action *a,
10297b99 286 struct tcf_result *res)
1da177e4 287{
e9ce1cd3 288 struct tcf_police *police = a->priv;
1da177e4 289 psched_time_t now;
1da177e4
LT
290 long toks;
291 long ptoks = 0;
292
e9ce1cd3 293 spin_lock(&police->tcf_lock);
1da177e4 294
bfe0d029 295 bstats_update(&police->tcf_bstats, skb);
1da177e4 296
e9ce1cd3
DM
297 if (police->tcfp_ewma_rate &&
298 police->tcf_rate_est.bps >= police->tcfp_ewma_rate) {
299 police->tcf_qstats.overlimits++;
b9647580
JP
300 if (police->tcf_action == TC_ACT_SHOT)
301 police->tcf_qstats.drops++;
e9ce1cd3
DM
302 spin_unlock(&police->tcf_lock);
303 return police->tcf_action;
1da177e4 304 }
1da177e4 305
0abf77e5 306 if (qdisc_pkt_len(skb) <= police->tcfp_mtu) {
e9ce1cd3
DM
307 if (police->tcfp_R_tab == NULL) {
308 spin_unlock(&police->tcf_lock);
309 return police->tcfp_result;
1da177e4
LT
310 }
311
3bebcda2 312 now = psched_get_time();
03cc45c0
PM
313 toks = psched_tdiff_bounded(now, police->tcfp_t_c,
314 police->tcfp_burst);
e9ce1cd3
DM
315 if (police->tcfp_P_tab) {
316 ptoks = toks + police->tcfp_ptoks;
317 if (ptoks > (long)L2T_P(police, police->tcfp_mtu))
318 ptoks = (long)L2T_P(police, police->tcfp_mtu);
0abf77e5 319 ptoks -= L2T_P(police, qdisc_pkt_len(skb));
1da177e4 320 }
e9ce1cd3
DM
321 toks += police->tcfp_toks;
322 if (toks > (long)police->tcfp_burst)
323 toks = police->tcfp_burst;
0abf77e5 324 toks -= L2T(police, qdisc_pkt_len(skb));
1da177e4 325 if ((toks|ptoks) >= 0) {
e9ce1cd3
DM
326 police->tcfp_t_c = now;
327 police->tcfp_toks = toks;
328 police->tcfp_ptoks = ptoks;
329 spin_unlock(&police->tcf_lock);
330 return police->tcfp_result;
1da177e4
LT
331 }
332 }
333
e9ce1cd3 334 police->tcf_qstats.overlimits++;
b9647580
JP
335 if (police->tcf_action == TC_ACT_SHOT)
336 police->tcf_qstats.drops++;
e9ce1cd3
DM
337 spin_unlock(&police->tcf_lock);
338 return police->tcf_action;
1da177e4
LT
339}
340
341static int
342tcf_act_police_dump(struct sk_buff *skb, struct tc_action *a, int bind, int ref)
343{
27a884dc 344 unsigned char *b = skb_tail_pointer(skb);
e9ce1cd3 345 struct tcf_police *police = a->priv;
0f04cfd0
JM
346 struct tc_police opt = {
347 .index = police->tcf_index,
348 .action = police->tcf_action,
349 .mtu = police->tcfp_mtu,
350 .burst = police->tcfp_burst,
351 .refcnt = police->tcf_refcnt - ref,
352 .bindcnt = police->tcf_bindcnt - bind,
353 };
354
e9ce1cd3
DM
355 if (police->tcfp_R_tab)
356 opt.rate = police->tcfp_R_tab->rate;
e9ce1cd3
DM
357 if (police->tcfp_P_tab)
358 opt.peakrate = police->tcfp_P_tab->rate;
1b34ec43
DM
359 if (nla_put(skb, TCA_POLICE_TBF, sizeof(opt), &opt))
360 goto nla_put_failure;
361 if (police->tcfp_result &&
362 nla_put_u32(skb, TCA_POLICE_RESULT, police->tcfp_result))
363 goto nla_put_failure;
364 if (police->tcfp_ewma_rate &&
365 nla_put_u32(skb, TCA_POLICE_AVRATE, police->tcfp_ewma_rate))
366 goto nla_put_failure;
1da177e4
LT
367 return skb->len;
368
7ba699c6 369nla_put_failure:
dc5fc579 370 nlmsg_trim(skb, b);
1da177e4
LT
371 return -1;
372}
373
374MODULE_AUTHOR("Alexey Kuznetsov");
375MODULE_DESCRIPTION("Policing actions");
376MODULE_LICENSE("GPL");
377
378static struct tc_action_ops act_police_ops = {
379 .kind = "police",
e9ce1cd3 380 .hinfo = &police_hash_info,
1da177e4
LT
381 .type = TCA_ID_POLICE,
382 .capab = TCA_CAP_NONE,
383 .owner = THIS_MODULE,
384 .act = tcf_act_police,
385 .dump = tcf_act_police_dump,
386 .cleanup = tcf_act_police_cleanup,
e9ce1cd3 387 .lookup = tcf_hash_search,
1da177e4 388 .init = tcf_act_police_locate,
83b950c8 389 .walk = tcf_act_police_walker
1da177e4
LT
390};
391
392static int __init
393police_init_module(void)
394{
395 return tcf_register_action(&act_police_ops);
396}
397
398static void __exit
399police_cleanup_module(void)
400{
401 tcf_unregister_action(&act_police_ops);
402}
403
404module_init(police_init_module);
405module_exit(police_cleanup_module);