summaryrefslogtreecommitdiffstats
path: root/net/sched/act_police.c
blob: 616f465f407e03d33feaffc17f45a937fb3fcd23 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
/*
 * net/sched/police.c	Input police filter.
 *
 *		This program is free software; you can redistribute it and/or
 *		modify it under the terms of the GNU General Public License
 *		as published by the Free Software Foundation; either version
 *		2 of the License, or (at your option) any later version.
 *
 * Authors:	Alexey Kuznetsov, <kuznet@ms2.inr.ac.ru>
 * 		J Hadi Salim (action changes)
 */

#include <asm/uaccess.h>
#include <asm/system.h>
#include <linux/bitops.h>
#include <linux/module.h>
#include <linux/types.h>
#include <linux/kernel.h>
#include <linux/string.h>
#include <linux/mm.h>
#include <linux/socket.h>
#include <linux/sockios.h>
#include <linux/in.h>
#include <linux/errno.h>
#include <linux/interrupt.h>
#include <linux/netdevice.h>
#include <linux/skbuff.h>
#include <linux/module.h>
#include <linux/rtnetlink.h>
#include <linux/init.h>
#include <net/sock.h>
#include <net/act_api.h>
#include <net/netlink.h>

#define L2T(p,L)   ((p)->tcfp_R_tab->data[(L)>>(p)->tcfp_R_tab->rate.cell_log])
#define L2T_P(p,L) ((p)->tcfp_P_tab->data[(L)>>(p)->tcfp_P_tab->rate.cell_log])

#define POL_TAB_MASK     15
static struct tcf_common *tcf_police_ht[POL_TAB_MASK + 1];
static u32 police_idx_gen;
static DEFINE_RWLOCK(police_lock);

static struct tcf_hashinfo police_hash_info = {
	.htab	=	tcf_police_ht,
	.hmask	=	POL_TAB_MASK,
	.lock	=	&police_lock,
};

/* old policer structure from before tc actions */
struct tc_police_compat
{
	u32			index;
	int			action;
	u32			limit;
	u32			burst;
	u32			mtu;
	struct tc_ratespec	rate;
	struct tc_ratespec	peakrate;
};

/* Each policer is serialized by its individual spinlock */

#ifdef CONFIG_NET_CLS_ACT
static int tcf_act_police_walker(struct sk_buff *skb, struct netlink_callback *cb,
			      int type, struct tc_action *a)
{
	struct tcf_common *p;
	int err = 0, index = -1, i = 0, s_i = 0, n_i = 0;
	struct rtattr *r;

	read_lock(&police_lock);

	s_i = cb->args[0];

	for (i = 0; i < (POL_TAB_MASK + 1); i++) {
		p = tcf_police_ht[tcf_hash(i, POL_TAB_MASK)];

		for (; p; p = p->tcfc_next) {
			index++;
			if (index < s_i)
				continue;
			a->priv = p;
			a->order = index;
			r = (struct rtattr *)skb_tail_pointer(skb);
			RTA_PUT(skb, a->order, 0, NULL);
			if (type == RTM_DELACTION)
				err = tcf_action_dump_1(skb, a, 0, 1);
			else
				err = tcf_action_dump_1(skb, a, 0, 0);
			if (err < 0) {
				index--;
				nlmsg_trim(skb, r);
				goto done;
			}
			r->rta_len = skb_tail_pointer(skb) - (u8 *)r;
			n_i++;
		}
	}
done:
	read_unlock(&police_lock);
	if (n_i)
		cb->args[0] += n_i;
	return n_i;

rtattr_failure:
	nlmsg_trim(skb, r);
	goto done;
}
#endif

void tcf_police_destroy(struct tcf_police *p)
{
	unsigned int h = tcf_hash(p->tcf_index, POL_TAB_MASK);
	struct tcf_common **p1p;

	for (p1p = &tcf_police_ht[h]; *p1p; p1p = &(*p1p)->tcfc_next) {
		if (*p1p == &p->common) {
			write_lock_bh(&police_lock);
			*p1p = p->tcf_next;
			write_unlock_bh(&police_lock);
#ifdef CONFIG_NET_ESTIMATOR
			gen_kill_estimator(&p->tcf_bstats,
					   &p->tcf_rate_est);
#endif
			if (p->tcfp_R_tab)
				qdisc_put_rtab(p->tcfp_R_tab);
			if (p->tcfp_P_tab)
				qdisc_put_rtab(p->tcfp_P_tab);
			kfree(p);
			return;
		}
	}
	BUG_TRAP(0);
}

#ifdef CONFIG_NET_CLS_ACT
static int tcf_act_police_locate(struct rtattr *rta, struct rtattr *est,
				 struct tc_action *a, int ovr, int bind)
{
	unsigned h;
	int ret = 0, err;
	struct rtattr *tb[TCA_POLICE_MAX];
	struct tc_police *parm;
	struct tcf_police *police;
	struct qdisc_rate_table *R_tab = NULL, *P_tab = NULL;
	int size;

	if (rta == NULL || rtattr_parse_nested(tb, TCA_POLICE_MAX, rta) < 0)
		return -EINVAL;

	if (tb[TCA_POLICE_TBF-1] == NULL)
		return -EINVAL;
	size = RTA_PAYLOAD(tb[TCA_POLICE_TBF-1]);
	if (size != sizeof(*parm) && size != sizeof(struct tc_police_compat))
		return -EINVAL;
	parm = RTA_DATA(tb[TCA_POLICE_TBF-1]);

	if (tb[TCA_POLICE_RESULT-1] != NULL &&
	    RTA_PAYLOAD(tb[TCA_POLICE_RESULT-1]) != sizeof(u32))
		return -EINVAL;
	if (tb[TCA_POLICE_RESULT-1] != NULL &&
	    RTA_PAYLOAD(tb[TCA_POLICE_RESULT-1]) != sizeof(u32))
		return -EINVAL;

	if (parm->index) {
		struct tcf_common *pc;

		pc = tcf_hash_lookup(parm->index, &police_hash_info);
		if (pc != NULL) {
			a->priv = pc;
			police = to_police(pc);
			if (bind) {
				police->tcf_bindcnt += 1;
				police->tcf_refcnt += 1;
			}
			if (ovr)
				goto override;
			return ret;
		}
	}

	police = kzalloc(sizeof(*police), GFP_KERNEL);
	if (police == NULL)
		return -ENOMEM;
	ret = ACT_P_CREATED;
	police->tcf_refcnt = 1;
	spin_lock_init(&police->tcf_lock);
	police->tcf_stats_lock = &police->tcf_lock;
	if (bind)
		police->tcf_bindcnt = 1;
override:
	if (parm->rate.rate) {
		err = -ENOMEM;
		R_tab = qdisc_get_rtab(&parm->rate, tb[TCA_POLICE_RATE-1]);
		if (R_tab == NULL)
			goto failure;
		if (parm->peakrate.rate) {
			P_tab = qdisc_get_rtab(&parm->peakrate,
					       tb[TCA_POLICE_PEAKRATE-1]);
			if (P_tab == NULL) {
				qdisc_put_rtab(R_tab);
				goto failure;
			}
		}
	}
	/* No failure allowed after this point */
	spin_lock_bh(&police->tcf_lock);
	if (R_tab != NULL) {
		qdisc_put_rtab(police->tcfp_R_tab);
		police->tcfp_R_tab = R_tab;
	}
	if (P_tab != NULL) {
		qdisc_put_rtab(police->tcfp_P_tab);
		police->tcfp_P_tab = P_tab;
	}

	if (tb[TCA_POLICE_RESULT-1])
		police->tcfp_result = *(u32*)RTA_DATA(tb[TCA_POLICE_RESULT-1]);
	police->tcfp_toks = police->tcfp_burst = parm->burst;
	police->tcfp_mtu = parm->mtu;
	if (police->tcfp_mtu == 0) {
		police->tcfp_mtu = ~0;
		if (police->tcfp_R_tab)
			police->tcfp_mtu = 255<<police->tcfp_R_tab->rate.cell_log;
	}
	if (police->tcfp_P_tab)
		police->tcfp_ptoks = L2T_P(police, police->tcfp_mtu);
	police->tcf_action = parm->action;

#ifdef CONFIG_NET_ESTIMATOR
	if (tb[TCA_POLICE_AVRATE-1])
		police->tcfp_ewma_rate =
			*(u32*)RTA_DATA(tb[TCA_POLICE_AVRATE-1]);
	if (est)
		gen_replace_estimator(&police->tcf_bstats,
				      &police->tcf_rate_est,
				      police->tcf_stats_lock, est);
#endif

	spin_unlock_bh(&police->tcf_lock);
	if (ret != ACT_P_CREATED)
		return ret;

	police->tcfp_t_c = psched_get_time();
	police->tcf_index = parm->index ? parm->index :
		tcf_hash_new_index(&police_idx_gen, &police_hash_info);
	h = tcf_hash(police->tcf_index, POL_TAB_MASK);
	write_lock_bh(&police_lock);
	police->tcf_next = tcf_police_ht[h];
	tcf_police_ht[h] = &police->common;
	write_unlock_bh(&police_lock);

	a->priv = police;
	return ret;

failure:
	if (ret == ACT_P_CREATED)
		kfree(police);
	return err;
}

static int tcf_act_police_cleanup(struct tc_action *a, int bind)
{
	struct tcf_police *p = a->priv;

	if (p != NULL)
		return tcf_police_release(p, bind);
	return 0;
}

static int tcf_act_police(struct sk_buff *skb, struct tc_action *a,
			  struct tcf_result *res)
{
	struct tcf_police *police = a->priv;
	psched_time_t now;
	long toks;
	long ptoks = 0;

	spin_lock(&police->tcf_lock);

	police->tcf_bstats.bytes += skb->len;
	police->tcf_bstats.packets++;

#ifdef CONFIG_NET_ESTIMATOR
	if (police->tcfp_ewma_rate &&
	    police->tcf_rate_est.bps >= police->tcfp_ewma_rate) {
		police->tcf_qstats.overlimits++;
		spin_unlock(&police->tcf_lock);
		return police->tcf_action;
	}
#endif

	if (skb->len <= police->tcfp_mtu) {
		if (police->tcfp_R_tab == NULL) {
			spin_unlock(&police->tcf_lock);
			return police->tcfp_result;
		}

		now = psched_get_time();
		toks = psched_tdiff_bounded(now, police->tcfp_t_c,
					    police->tcfp_burst);
		if (police->tcfp_P_tab) {
			ptoks = toks + police->tcfp_ptoks;
			if (ptoks > (long)L2T_P(police, police->tcfp_mtu))
				ptoks = (long)L2T_P(police, police->tcfp_mtu);
			ptoks -= L2T_P(police, skb->len);
		}
		toks += police->tcfp_toks;
		if (toks > (long)police->tcfp_burst)
			toks = police->tcfp_burst;
		toks -= L2T(police, skb->len);
		if ((toks|ptoks) >= 0) {
			police->tcfp_t_c = now;
			police->tcfp_toks = toks;
			police->tcfp_ptoks = ptoks;
			spin_unlock(&police->tcf_lock);
			return police->tcfp_result;
		}
	}

	police->tcf_qstats.overlimits++;
	spin_unlock(&police->tcf_lock);
	return police->tcf_action;
}

static int
tcf_act_police_dump(struct sk_buff *skb, struct tc_action *a, int bind, int ref)
{
	unsigned char *b = skb_tail_pointer(skb);
	struct tcf_police *police = a->priv;
	struct tc_police opt;

	opt.index = police->tcf_index;
	opt.action = police->tcf_action;
	opt.mtu = police->tcfp_mtu;
	opt.burst = police->tcfp_burst;
	opt.refcnt = police->tcf_refcnt - ref;
	opt.bindcnt = police->tcf_bindcnt - bind;
	if (police->tcfp_R_tab)
		opt.rate = police->tcfp_R_tab->rate;
	else
		memset(&opt.rate, 0, sizeof(opt.rate));
	if (police->tcfp_P_tab)
		opt.peakrate = police->tcfp_P_tab->rate;
	else
		memset(&opt.peakrate, 0, sizeof(opt.peakrate));
	RTA_PUT(skb, TCA_POLICE_TBF, sizeof(opt), &opt);
	if (police->tcfp_result)
		RTA_PUT(skb, TCA_POLICE_RESULT, sizeof(int),
			&police->tcfp_result);
#ifdef CONFIG_NET_ESTIMATOR
	if (police->tcfp_ewma_rate)
		RTA_PUT(skb, TCA_POLICE_AVRATE, 4, &police->tcfp_ewma_rate);
#endif
	return skb->len;

rtattr_failure:
	nlmsg_trim(skb, b);
	return -1;
}

MODULE_AUTHOR("Alexey Kuznetsov");
MODULE_DESCRIPTION("Policing actions");
MODULE_LICENSE("GPL");

static struct tc_action_ops act_police_ops = {
	.kind		=	"police",
	.hinfo		=	&police_hash_info,
	.type		=	TCA_ID_POLICE,
	.capab		=	TCA_CAP_NONE,
	.owner		=	THIS_MODULE,
	.act		=	tcf_act_police,
	.dump		=	tcf_act_police_dump,
	.cleanup	=	tcf_act_police_cleanup,
	.lookup		=	tcf_hash_search,
	.init		=	tcf_act_police_locate,
	.walk		=	tcf_act_police_walker
};

static int __init
police_init_module(void)
{
	return tcf_register_action(&act_police_ops);
}

static void __exit
police_cleanup_module(void)
{
	tcf_unregister_action(&act_police_ops);
}

module_init(police_init_module);
module_exit(police_cleanup_module);

#else /* CONFIG_NET_CLS_ACT */

static struct tcf_common *tcf_police_lookup(u32 index)
{
	struct tcf_hashinfo *hinfo = &police_hash_info;
	struct tcf_common *p;

	read_lock(hinfo->lock);
	for (p = hinfo->htab[tcf_hash(index, hinfo->hmask)]; p;
	     p = p->tcfc_next) {
		if (p->tcfc_index == index)
			break;
	}
	read_unlock(hinfo->lock);

	return p;
}

static u32 tcf_police_new_index(void)
{
	u32 *idx_gen = &police_idx_gen;
	u32 val = *idx_gen;

	do {
		if (++val == 0)
			val = 1;
	} while (tcf_police_lookup(val));

	return (*idx_gen = val);
}

struct tcf_police *tcf_police_locate(struct rtattr *rta, struct rtattr *est)
{
	unsigned int h;
	struct tcf_police *police;
	struct rtattr *tb[TCA_POLICE_MAX];
	struct tc_police *parm;
	int size;

	if (rtattr_parse_nested(tb, TCA_POLICE_MAX, rta) < 0)
		return NULL;

	if (tb[TCA_POLICE_TBF-1] == NULL)
		return NULL;
	size = RTA_PAYLOAD(tb[TCA_POLICE_TBF-1]);
	if (size != sizeof(*parm) && size != sizeof(struct tc_police_compat))
		return NULL;

	parm = RTA_DATA(tb[TCA_POLICE_TBF-1]);

	if (parm->index) {
		struct tcf_common *pc;

		pc = tcf_police_lookup(parm->index);
		if (pc) {
			police = to_police(pc);
			police->tcf_refcnt++;
			return police;
		}
	}
	police = kzalloc(sizeof(*police), GFP_KERNEL);
	if (unlikely(!police))
		return NULL;

	police->tcf_refcnt = 1;
	spin_lock_init(&police->tcf_lock);
	police->tcf_stats_lock = &police->tcf_lock;
	if (parm->rate.rate) {
		police->tcfp_R_tab =
			qdisc_get_rtab(&parm->rate, tb[TCA_POLICE_RATE-1]);
		if (police->tcfp_R_tab == NULL)
			goto failure;
		if (parm->peakrate.rate) {
			police->tcfp_P_tab =
				qdisc_get_rtab(&parm->peakrate,
					       tb[TCA_POLICE_PEAKRATE-1]);
			if (police->tcfp_P_tab == NULL)
				goto failure;
		}
	}
	if (tb[TCA_POLICE_RESULT-1]) {
		if (RTA_PAYLOAD(tb[TCA_POLICE_RESULT-1]) != sizeof(u32))
			goto failure;
		police->tcfp_result = *(u32*)RTA_DATA(tb[TCA_POLICE_RESULT-1]);
	}
#ifdef CONFIG_NET_ESTIMATOR
	if (tb[TCA_POLICE_AVRATE-1]) {
		if (RTA_PAYLOAD(tb[TCA_POLICE_AVRATE-1]) != sizeof(u32))
			goto failure;
		police->tcfp_ewma_rate =
			*(u32*)RTA_DATA(tb[TCA_POLICE_AVRATE-1]);
	}
#endif
	police->tcfp_toks = police->tcfp_burst = parm->burst;
	police->tcfp_mtu = parm->mtu;
	if (police->tcfp_mtu == 0) {
		police->tcfp_mtu = ~0;
		if (police->tcfp_R_tab)
			police->tcfp_mtu = 255<<police->tcfp_R_tab->rate.cell_log;
	}
	if (police->tcfp_P_tab)
		police->tcfp_ptoks = L2T_P(police, police->tcfp_mtu);
	police->tcfp_t_c = psched_get_time();
	police->tcf_index = parm->index ? parm->index :
		tcf_police_new_index();
	police->tcf_action = parm->action;
#ifdef CONFIG_NET_ESTIMATOR
	if (est)
		gen_new_estimator(&police->tcf_bstats, &police->tcf_rate_est,
				  police->tcf_stats_lock, est);
#endif
	h = tcf_hash(police->tcf_index, POL_TAB_MASK);
	write_lock_bh(&police_lock);
	police->tcf_next = tcf_police_ht[h];
	tcf_police_ht[h] = &police->common;
	write_unlock_bh(&police_lock);
	return police;

failure:
	if (police->tcfp_R_tab)
		qdisc_put_rtab(police->tcfp_R_tab);
	kfree(police);
	return NULL;
}

int tcf_police(struct sk_buff *skb, struct tcf_police *police)
{
	psched_time_t now;
	long toks;
	long ptoks = 0;

	spin_lock(&police->tcf_lock);

	police->tcf_bstats.bytes += skb->len;
	police->tcf_bstats.packets++;

#ifdef CONFIG_NET_ESTIMATOR
	if (police->tcfp_ewma_rate &&
	    police->tcf_rate_est.bps >= police->tcfp_ewma_rate) {
		police->tcf_qstats.overlimits++;
		spin_unlock(&police->tcf_lock);
		return police->tcf_action;
	}
#endif
	if (skb->len <= police->tcfp_mtu) {
		if (police->tcfp_R_tab == NULL) {
			spin_unlock(&police->tcf_lock);
			return police->tcfp_result;
		}

		now = psched_get_time();
		toks = psched_tdiff_bounded(now, police->tcfp_t_c,
					    police->tcfp_burst);
		if (police->tcfp_P_tab) {
			ptoks = toks + police->tcfp_ptoks;
			if (ptoks > (long)L2T_P(police, police->tcfp_mtu))
				ptoks = (long)L2T_P(police, police->tcfp_mtu);
			ptoks -= L2T_P(police, skb->len);
		}
		toks += police->tcfp_toks;
		if (toks > (long)police->tcfp_burst)
			toks = police->tcfp_burst;
		toks -= L2T(police, skb->len);
		if ((toks|ptoks) >= 0) {
			police->tcfp_t_c = now;
			police->tcfp_toks = toks;
			police->tcfp_ptoks = ptoks;
			spin_unlock(&police->tcf_lock);
			return police->tcfp_result;
		}
	}

	police->tcf_qstats.overlimits++;
	spin_unlock(&police->tcf_lock);
	return police->tcf_action;
}
EXPORT_SYMBOL(tcf_police);

int tcf_police_dump(struct sk_buff *skb, struct tcf_police *police)
{
	unsigned char *b = skb_tail_pointer(skb);
	struct tc_police opt;

	opt.index = police->tcf_index;
	opt.action = police->tcf_action;
	opt.mtu = police->tcfp_mtu;
	opt.burst = police->tcfp_burst;
	if (police->tcfp_R_tab)
		opt.rate = police->tcfp_R_tab->rate;
	else
		memset(&opt.rate, 0, sizeof(opt.rate));
	if (police->tcfp_P_tab)
		opt.peakrate = police->tcfp_P_tab->rate;
	else
		memset(&opt.peakrate, 0, sizeof(opt.peakrate));
	RTA_PUT(skb, TCA_POLICE_TBF, sizeof(opt), &opt);
	if (police->tcfp_result)
		RTA_PUT(skb, TCA_POLICE_RESULT, sizeof(int),
			&police->tcfp_result);
#ifdef CONFIG_NET_ESTIMATOR
	if (police->tcfp_ewma_rate)
		RTA_PUT(skb, TCA_POLICE_AVRATE, 4, &police->tcfp_ewma_rate);
#endif
	return skb->len;

rtattr_failure:
	nlmsg_trim(skb, b);
	return -1;
}

int tcf_police_dump_stats(struct sk_buff *skb, struct tcf_police *police)
{
	struct gnet_dump d;

	if (gnet_stats_start_copy_compat(skb, TCA_STATS2, TCA_STATS,
					 TCA_XSTATS, police->tcf_stats_lock,
					 &d) < 0)
		goto errout;

	if (gnet_stats_copy_basic(&d, &police->tcf_bstats) < 0 ||
#ifdef CONFIG_NET_ESTIMATOR
	    gnet_stats_copy_rate_est(&d, &police->tcf_rate_est) < 0 ||
#endif
	    gnet_stats_copy_queue(&d, &police->tcf_qstats) < 0)
		goto errout;

	if (gnet_stats_finish_copy(&d) < 0)
		goto errout;

	return 0;

errout:
	return -1;
}

#endif /* CONFIG_NET_CLS_ACT */
OpenPOWER on IntegriCloud