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 <linux/slab.h>
22 #include <net/act_api.h>
23 #include <net/netlink.h>
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)
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
{
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
);
116 * gen_estimator est_timer() might access p->tcf_lock
117 * or bstats, wait a RCU grace period before freeing p
119 kfree_rcu(p
, tcf_rcu
);
126 static 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
},
133 static int tcf_act_police_locate(struct nlattr
*nla
, struct nlattr
*est
,
134 struct tc_action
*a
, int ovr
, int bind
)
138 struct nlattr
*tb
[TCA_POLICE_MAX
+ 1];
139 struct tc_police
*parm
;
140 struct tcf_police
*police
;
141 struct qdisc_rate_table
*R_tab
= NULL
, *P_tab
= NULL
;
147 err
= nla_parse_nested(tb
, TCA_POLICE_MAX
, nla
, police_policy
);
151 if (tb
[TCA_POLICE_TBF
] == NULL
)
153 size
= nla_len(tb
[TCA_POLICE_TBF
]);
154 if (size
!= sizeof(*parm
) && size
!= sizeof(struct tc_police_compat
))
156 parm
= nla_data(tb
[TCA_POLICE_TBF
]);
159 struct tcf_common
*pc
;
161 pc
= tcf_hash_lookup(parm
->index
, &police_hash_info
);
164 police
= to_police(pc
);
166 police
->tcf_bindcnt
+= 1;
167 police
->tcf_refcnt
+= 1;
175 police
= kzalloc(sizeof(*police
), GFP_KERNEL
);
179 police
->tcf_refcnt
= 1;
180 spin_lock_init(&police
->tcf_lock
);
182 police
->tcf_bindcnt
= 1;
184 if (parm
->rate
.rate
) {
186 R_tab
= qdisc_get_rtab(&parm
->rate
, tb
[TCA_POLICE_RATE
]);
190 if (parm
->peakrate
.rate
) {
191 P_tab
= qdisc_get_rtab(&parm
->peakrate
,
192 tb
[TCA_POLICE_PEAKRATE
]);
198 spin_lock_bh(&police
->tcf_lock
);
200 err
= gen_replace_estimator(&police
->tcf_bstats
,
201 &police
->tcf_rate_est
,
202 &police
->tcf_lock
, est
);
205 } else if (tb
[TCA_POLICE_AVRATE
] &&
206 (ret
== ACT_P_CREATED
||
207 !gen_estimator_active(&police
->tcf_bstats
,
208 &police
->tcf_rate_est
))) {
213 /* No failure allowed after this point */
215 qdisc_put_rtab(police
->tcfp_R_tab
);
216 police
->tcfp_R_tab
= R_tab
;
219 qdisc_put_rtab(police
->tcfp_P_tab
);
220 police
->tcfp_P_tab
= P_tab
;
223 if (tb
[TCA_POLICE_RESULT
])
224 police
->tcfp_result
= nla_get_u32(tb
[TCA_POLICE_RESULT
]);
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
;
232 if (police
->tcfp_P_tab
)
233 police
->tcfp_ptoks
= L2T_P(police
, police
->tcfp_mtu
);
234 police
->tcf_action
= parm
->action
;
236 if (tb
[TCA_POLICE_AVRATE
])
237 police
->tcfp_ewma_rate
= nla_get_u32(tb
[TCA_POLICE_AVRATE
]);
239 spin_unlock_bh(&police
->tcf_lock
);
240 if (ret
!= ACT_P_CREATED
)
243 police
->tcfp_t_c
= psched_get_time();
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
);
247 write_lock_bh(&police_lock
);
248 police
->tcf_next
= tcf_police_ht
[h
];
249 tcf_police_ht
[h
] = &police
->common
;
250 write_unlock_bh(&police_lock
);
256 spin_unlock_bh(&police
->tcf_lock
);
259 qdisc_put_rtab(P_tab
);
261 qdisc_put_rtab(R_tab
);
262 if (ret
== ACT_P_CREATED
)
267 static int tcf_act_police_cleanup(struct tc_action
*a
, int bind
)
269 struct tcf_police
*p
= a
->priv
;
277 if (p
->tcf_refcnt
<= 0 && !p
->tcf_bindcnt
) {
278 tcf_police_destroy(p
);
285 static int tcf_act_police(struct sk_buff
*skb
, const struct tc_action
*a
,
286 struct tcf_result
*res
)
288 struct tcf_police
*police
= a
->priv
;
293 spin_lock(&police
->tcf_lock
);
295 bstats_update(&police
->tcf_bstats
, skb
);
297 if (police
->tcfp_ewma_rate
&&
298 police
->tcf_rate_est
.bps
>= police
->tcfp_ewma_rate
) {
299 police
->tcf_qstats
.overlimits
++;
300 if (police
->tcf_action
== TC_ACT_SHOT
)
301 police
->tcf_qstats
.drops
++;
302 spin_unlock(&police
->tcf_lock
);
303 return police
->tcf_action
;
306 if (qdisc_pkt_len(skb
) <= police
->tcfp_mtu
) {
307 if (police
->tcfp_R_tab
== NULL
) {
308 spin_unlock(&police
->tcf_lock
);
309 return police
->tcfp_result
;
312 now
= psched_get_time();
313 toks
= psched_tdiff_bounded(now
, police
->tcfp_t_c
,
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
);
319 ptoks
-= L2T_P(police
, qdisc_pkt_len(skb
));
321 toks
+= police
->tcfp_toks
;
322 if (toks
> (long)police
->tcfp_burst
)
323 toks
= police
->tcfp_burst
;
324 toks
-= L2T(police
, qdisc_pkt_len(skb
));
325 if ((toks
|ptoks
) >= 0) {
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
;
334 police
->tcf_qstats
.overlimits
++;
335 if (police
->tcf_action
== TC_ACT_SHOT
)
336 police
->tcf_qstats
.drops
++;
337 spin_unlock(&police
->tcf_lock
);
338 return police
->tcf_action
;
342 tcf_act_police_dump(struct sk_buff
*skb
, struct tc_action
*a
, int bind
, int ref
)
344 unsigned char *b
= skb_tail_pointer(skb
);
345 struct tcf_police
*police
= a
->priv
;
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
,
355 if (police
->tcfp_R_tab
)
356 opt
.rate
= police
->tcfp_R_tab
->rate
;
357 if (police
->tcfp_P_tab
)
358 opt
.peakrate
= police
->tcfp_P_tab
->rate
;
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
;
374 MODULE_AUTHOR("Alexey Kuznetsov");
375 MODULE_DESCRIPTION("Policing actions");
376 MODULE_LICENSE("GPL");
378 static struct tc_action_ops act_police_ops
= {
380 .hinfo
= &police_hash_info
,
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
,
387 .lookup
= tcf_hash_search
,
388 .init
= tcf_act_police_locate
,
389 .walk
= tcf_act_police_walker
393 police_init_module(void)
395 return tcf_register_action(&act_police_ops
);
399 police_cleanup_module(void)
401 tcf_unregister_action(&act_police_ops
);
404 module_init(police_init_module
);
405 module_exit(police_cleanup_module
);