xref: /linux/net/sched/act_gate.c (revision 7a92fc8b4d20680e4c20289a670d8fca2d1f2c1b)
1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /* Copyright 2020 NXP */
3 
4 #include <linux/module.h>
5 #include <linux/types.h>
6 #include <linux/kernel.h>
7 #include <linux/string.h>
8 #include <linux/errno.h>
9 #include <linux/skbuff.h>
10 #include <linux/rtnetlink.h>
11 #include <linux/init.h>
12 #include <linux/slab.h>
13 #include <net/act_api.h>
14 #include <net/netlink.h>
15 #include <net/pkt_cls.h>
16 #include <net/tc_act/tc_gate.h>
17 #include <net/tc_wrapper.h>
18 
19 static struct tc_action_ops act_gate_ops;
20 
21 static ktime_t gate_get_time(struct tcf_gate *gact)
22 {
23 	ktime_t mono = ktime_get();
24 
25 	switch (gact->tk_offset) {
26 	case TK_OFFS_MAX:
27 		return mono;
28 	default:
29 		return ktime_mono_to_any(mono, gact->tk_offset);
30 	}
31 
32 	return KTIME_MAX;
33 }
34 
35 static void gate_get_start_time(struct tcf_gate *gact, ktime_t *start)
36 {
37 	struct tcf_gate_params *param = &gact->param;
38 	ktime_t now, base, cycle;
39 	u64 n;
40 
41 	base = ns_to_ktime(param->tcfg_basetime);
42 	now = gate_get_time(gact);
43 
44 	if (ktime_after(base, now)) {
45 		*start = base;
46 		return;
47 	}
48 
49 	cycle = param->tcfg_cycletime;
50 
51 	n = div64_u64(ktime_sub_ns(now, base), cycle);
52 	*start = ktime_add_ns(base, (n + 1) * cycle);
53 }
54 
55 static void gate_start_timer(struct tcf_gate *gact, ktime_t start)
56 {
57 	ktime_t expires;
58 
59 	expires = hrtimer_get_expires(&gact->hitimer);
60 	if (expires == 0)
61 		expires = KTIME_MAX;
62 
63 	start = min_t(ktime_t, start, expires);
64 
65 	hrtimer_start(&gact->hitimer, start, HRTIMER_MODE_ABS_SOFT);
66 }
67 
68 static enum hrtimer_restart gate_timer_func(struct hrtimer *timer)
69 {
70 	struct tcf_gate *gact = container_of(timer, struct tcf_gate,
71 					     hitimer);
72 	struct tcf_gate_params *p = &gact->param;
73 	struct tcfg_gate_entry *next;
74 	ktime_t close_time, now;
75 
76 	spin_lock(&gact->tcf_lock);
77 
78 	next = gact->next_entry;
79 
80 	/* cycle start, clear pending bit, clear total octets */
81 	gact->current_gate_status = next->gate_state ? GATE_ACT_GATE_OPEN : 0;
82 	gact->current_entry_octets = 0;
83 	gact->current_max_octets = next->maxoctets;
84 
85 	gact->current_close_time = ktime_add_ns(gact->current_close_time,
86 						next->interval);
87 
88 	close_time = gact->current_close_time;
89 
90 	if (list_is_last(&next->list, &p->entries))
91 		next = list_first_entry(&p->entries,
92 					struct tcfg_gate_entry, list);
93 	else
94 		next = list_next_entry(next, list);
95 
96 	now = gate_get_time(gact);
97 
98 	if (ktime_after(now, close_time)) {
99 		ktime_t cycle, base;
100 		u64 n;
101 
102 		cycle = p->tcfg_cycletime;
103 		base = ns_to_ktime(p->tcfg_basetime);
104 		n = div64_u64(ktime_sub_ns(now, base), cycle);
105 		close_time = ktime_add_ns(base, (n + 1) * cycle);
106 	}
107 
108 	gact->next_entry = next;
109 
110 	hrtimer_set_expires(&gact->hitimer, close_time);
111 
112 	spin_unlock(&gact->tcf_lock);
113 
114 	return HRTIMER_RESTART;
115 }
116 
117 TC_INDIRECT_SCOPE int tcf_gate_act(struct sk_buff *skb,
118 				   const struct tc_action *a,
119 				   struct tcf_result *res)
120 {
121 	struct tcf_gate *gact = to_gate(a);
122 	int action = READ_ONCE(gact->tcf_action);
123 
124 	tcf_lastuse_update(&gact->tcf_tm);
125 	tcf_action_update_bstats(&gact->common, skb);
126 
127 	spin_lock(&gact->tcf_lock);
128 	if (unlikely(gact->current_gate_status & GATE_ACT_PENDING)) {
129 		spin_unlock(&gact->tcf_lock);
130 		return action;
131 	}
132 
133 	if (!(gact->current_gate_status & GATE_ACT_GATE_OPEN)) {
134 		spin_unlock(&gact->tcf_lock);
135 		goto drop;
136 	}
137 
138 	if (gact->current_max_octets >= 0) {
139 		gact->current_entry_octets += qdisc_pkt_len(skb);
140 		if (gact->current_entry_octets > gact->current_max_octets) {
141 			spin_unlock(&gact->tcf_lock);
142 			goto overlimit;
143 		}
144 	}
145 	spin_unlock(&gact->tcf_lock);
146 
147 	return action;
148 
149 overlimit:
150 	tcf_action_inc_overlimit_qstats(&gact->common);
151 drop:
152 	tcf_action_inc_drop_qstats(&gact->common);
153 	return TC_ACT_SHOT;
154 }
155 
156 static const struct nla_policy entry_policy[TCA_GATE_ENTRY_MAX + 1] = {
157 	[TCA_GATE_ENTRY_INDEX]		= { .type = NLA_U32 },
158 	[TCA_GATE_ENTRY_GATE]		= { .type = NLA_FLAG },
159 	[TCA_GATE_ENTRY_INTERVAL]	= { .type = NLA_U32 },
160 	[TCA_GATE_ENTRY_IPV]		= { .type = NLA_S32 },
161 	[TCA_GATE_ENTRY_MAX_OCTETS]	= { .type = NLA_S32 },
162 };
163 
164 static const struct nla_policy gate_policy[TCA_GATE_MAX + 1] = {
165 	[TCA_GATE_PARMS]		=
166 		NLA_POLICY_EXACT_LEN(sizeof(struct tc_gate)),
167 	[TCA_GATE_PRIORITY]		= { .type = NLA_S32 },
168 	[TCA_GATE_ENTRY_LIST]		= { .type = NLA_NESTED },
169 	[TCA_GATE_BASE_TIME]		= { .type = NLA_U64 },
170 	[TCA_GATE_CYCLE_TIME]		= { .type = NLA_U64 },
171 	[TCA_GATE_CYCLE_TIME_EXT]	= { .type = NLA_U64 },
172 	[TCA_GATE_FLAGS]		= { .type = NLA_U32 },
173 	[TCA_GATE_CLOCKID]		= { .type = NLA_S32 },
174 };
175 
176 static int fill_gate_entry(struct nlattr **tb, struct tcfg_gate_entry *entry,
177 			   struct netlink_ext_ack *extack)
178 {
179 	u32 interval = 0;
180 
181 	entry->gate_state = nla_get_flag(tb[TCA_GATE_ENTRY_GATE]);
182 
183 	if (tb[TCA_GATE_ENTRY_INTERVAL])
184 		interval = nla_get_u32(tb[TCA_GATE_ENTRY_INTERVAL]);
185 
186 	if (interval == 0) {
187 		NL_SET_ERR_MSG(extack, "Invalid interval for schedule entry");
188 		return -EINVAL;
189 	}
190 
191 	entry->interval = interval;
192 
193 	if (tb[TCA_GATE_ENTRY_IPV])
194 		entry->ipv = nla_get_s32(tb[TCA_GATE_ENTRY_IPV]);
195 	else
196 		entry->ipv = -1;
197 
198 	if (tb[TCA_GATE_ENTRY_MAX_OCTETS])
199 		entry->maxoctets = nla_get_s32(tb[TCA_GATE_ENTRY_MAX_OCTETS]);
200 	else
201 		entry->maxoctets = -1;
202 
203 	return 0;
204 }
205 
206 static int parse_gate_entry(struct nlattr *n, struct  tcfg_gate_entry *entry,
207 			    int index, struct netlink_ext_ack *extack)
208 {
209 	struct nlattr *tb[TCA_GATE_ENTRY_MAX + 1] = { };
210 	int err;
211 
212 	err = nla_parse_nested(tb, TCA_GATE_ENTRY_MAX, n, entry_policy, extack);
213 	if (err < 0) {
214 		NL_SET_ERR_MSG(extack, "Could not parse nested entry");
215 		return -EINVAL;
216 	}
217 
218 	entry->index = index;
219 
220 	return fill_gate_entry(tb, entry, extack);
221 }
222 
223 static void release_entry_list(struct list_head *entries)
224 {
225 	struct tcfg_gate_entry *entry, *e;
226 
227 	list_for_each_entry_safe(entry, e, entries, list) {
228 		list_del(&entry->list);
229 		kfree(entry);
230 	}
231 }
232 
233 static int parse_gate_list(struct nlattr *list_attr,
234 			   struct tcf_gate_params *sched,
235 			   struct netlink_ext_ack *extack)
236 {
237 	struct tcfg_gate_entry *entry;
238 	struct nlattr *n;
239 	int err, rem;
240 	int i = 0;
241 
242 	if (!list_attr)
243 		return -EINVAL;
244 
245 	nla_for_each_nested(n, list_attr, rem) {
246 		if (nla_type(n) != TCA_GATE_ONE_ENTRY) {
247 			NL_SET_ERR_MSG(extack, "Attribute isn't type 'entry'");
248 			continue;
249 		}
250 
251 		entry = kzalloc(sizeof(*entry), GFP_ATOMIC);
252 		if (!entry) {
253 			NL_SET_ERR_MSG(extack, "Not enough memory for entry");
254 			err = -ENOMEM;
255 			goto release_list;
256 		}
257 
258 		err = parse_gate_entry(n, entry, i, extack);
259 		if (err < 0) {
260 			kfree(entry);
261 			goto release_list;
262 		}
263 
264 		list_add_tail(&entry->list, &sched->entries);
265 		i++;
266 	}
267 
268 	sched->num_entries = i;
269 
270 	return i;
271 
272 release_list:
273 	release_entry_list(&sched->entries);
274 
275 	return err;
276 }
277 
278 static void gate_setup_timer(struct tcf_gate *gact, u64 basetime,
279 			     enum tk_offsets tko, s32 clockid,
280 			     bool do_init)
281 {
282 	if (!do_init) {
283 		if (basetime == gact->param.tcfg_basetime &&
284 		    tko == gact->tk_offset &&
285 		    clockid == gact->param.tcfg_clockid)
286 			return;
287 
288 		spin_unlock_bh(&gact->tcf_lock);
289 		hrtimer_cancel(&gact->hitimer);
290 		spin_lock_bh(&gact->tcf_lock);
291 	}
292 	gact->param.tcfg_basetime = basetime;
293 	gact->param.tcfg_clockid = clockid;
294 	gact->tk_offset = tko;
295 	hrtimer_init(&gact->hitimer, clockid, HRTIMER_MODE_ABS_SOFT);
296 	gact->hitimer.function = gate_timer_func;
297 }
298 
299 static int tcf_gate_init(struct net *net, struct nlattr *nla,
300 			 struct nlattr *est, struct tc_action **a,
301 			 struct tcf_proto *tp, u32 flags,
302 			 struct netlink_ext_ack *extack)
303 {
304 	struct tc_action_net *tn = net_generic(net, act_gate_ops.net_id);
305 	enum tk_offsets tk_offset = TK_OFFS_TAI;
306 	bool bind = flags & TCA_ACT_FLAGS_BIND;
307 	struct nlattr *tb[TCA_GATE_MAX + 1];
308 	struct tcf_chain *goto_ch = NULL;
309 	u64 cycletime = 0, basetime = 0;
310 	struct tcf_gate_params *p;
311 	s32 clockid = CLOCK_TAI;
312 	struct tcf_gate *gact;
313 	struct tc_gate *parm;
314 	int ret = 0, err;
315 	u32 gflags = 0;
316 	s32 prio = -1;
317 	ktime_t start;
318 	u32 index;
319 
320 	if (!nla)
321 		return -EINVAL;
322 
323 	err = nla_parse_nested(tb, TCA_GATE_MAX, nla, gate_policy, extack);
324 	if (err < 0)
325 		return err;
326 
327 	if (!tb[TCA_GATE_PARMS])
328 		return -EINVAL;
329 
330 	if (tb[TCA_GATE_CLOCKID]) {
331 		clockid = nla_get_s32(tb[TCA_GATE_CLOCKID]);
332 		switch (clockid) {
333 		case CLOCK_REALTIME:
334 			tk_offset = TK_OFFS_REAL;
335 			break;
336 		case CLOCK_MONOTONIC:
337 			tk_offset = TK_OFFS_MAX;
338 			break;
339 		case CLOCK_BOOTTIME:
340 			tk_offset = TK_OFFS_BOOT;
341 			break;
342 		case CLOCK_TAI:
343 			tk_offset = TK_OFFS_TAI;
344 			break;
345 		default:
346 			NL_SET_ERR_MSG(extack, "Invalid 'clockid'");
347 			return -EINVAL;
348 		}
349 	}
350 
351 	parm = nla_data(tb[TCA_GATE_PARMS]);
352 	index = parm->index;
353 
354 	err = tcf_idr_check_alloc(tn, &index, a, bind);
355 	if (err < 0)
356 		return err;
357 
358 	if (err && bind)
359 		return 0;
360 
361 	if (!err) {
362 		ret = tcf_idr_create_from_flags(tn, index, est, a,
363 						&act_gate_ops, bind, flags);
364 		if (ret) {
365 			tcf_idr_cleanup(tn, index);
366 			return ret;
367 		}
368 
369 		ret = ACT_P_CREATED;
370 	} else if (!(flags & TCA_ACT_FLAGS_REPLACE)) {
371 		tcf_idr_release(*a, bind);
372 		return -EEXIST;
373 	}
374 
375 	if (tb[TCA_GATE_PRIORITY])
376 		prio = nla_get_s32(tb[TCA_GATE_PRIORITY]);
377 
378 	if (tb[TCA_GATE_BASE_TIME])
379 		basetime = nla_get_u64(tb[TCA_GATE_BASE_TIME]);
380 
381 	if (tb[TCA_GATE_FLAGS])
382 		gflags = nla_get_u32(tb[TCA_GATE_FLAGS]);
383 
384 	gact = to_gate(*a);
385 	if (ret == ACT_P_CREATED)
386 		INIT_LIST_HEAD(&gact->param.entries);
387 
388 	err = tcf_action_check_ctrlact(parm->action, tp, &goto_ch, extack);
389 	if (err < 0)
390 		goto release_idr;
391 
392 	spin_lock_bh(&gact->tcf_lock);
393 	p = &gact->param;
394 
395 	if (tb[TCA_GATE_CYCLE_TIME])
396 		cycletime = nla_get_u64(tb[TCA_GATE_CYCLE_TIME]);
397 
398 	if (tb[TCA_GATE_ENTRY_LIST]) {
399 		err = parse_gate_list(tb[TCA_GATE_ENTRY_LIST], p, extack);
400 		if (err < 0)
401 			goto chain_put;
402 	}
403 
404 	if (!cycletime) {
405 		struct tcfg_gate_entry *entry;
406 		ktime_t cycle = 0;
407 
408 		list_for_each_entry(entry, &p->entries, list)
409 			cycle = ktime_add_ns(cycle, entry->interval);
410 		cycletime = cycle;
411 		if (!cycletime) {
412 			err = -EINVAL;
413 			goto chain_put;
414 		}
415 	}
416 	p->tcfg_cycletime = cycletime;
417 
418 	if (tb[TCA_GATE_CYCLE_TIME_EXT])
419 		p->tcfg_cycletime_ext =
420 			nla_get_u64(tb[TCA_GATE_CYCLE_TIME_EXT]);
421 
422 	gate_setup_timer(gact, basetime, tk_offset, clockid,
423 			 ret == ACT_P_CREATED);
424 	p->tcfg_priority = prio;
425 	p->tcfg_flags = gflags;
426 	gate_get_start_time(gact, &start);
427 
428 	gact->current_close_time = start;
429 	gact->current_gate_status = GATE_ACT_GATE_OPEN | GATE_ACT_PENDING;
430 
431 	gact->next_entry = list_first_entry(&p->entries,
432 					    struct tcfg_gate_entry, list);
433 
434 	goto_ch = tcf_action_set_ctrlact(*a, parm->action, goto_ch);
435 
436 	gate_start_timer(gact, start);
437 
438 	spin_unlock_bh(&gact->tcf_lock);
439 
440 	if (goto_ch)
441 		tcf_chain_put_by_act(goto_ch);
442 
443 	return ret;
444 
445 chain_put:
446 	spin_unlock_bh(&gact->tcf_lock);
447 
448 	if (goto_ch)
449 		tcf_chain_put_by_act(goto_ch);
450 release_idr:
451 	/* action is not inserted in any list: it's safe to init hitimer
452 	 * without taking tcf_lock.
453 	 */
454 	if (ret == ACT_P_CREATED)
455 		gate_setup_timer(gact, gact->param.tcfg_basetime,
456 				 gact->tk_offset, gact->param.tcfg_clockid,
457 				 true);
458 	tcf_idr_release(*a, bind);
459 	return err;
460 }
461 
462 static void tcf_gate_cleanup(struct tc_action *a)
463 {
464 	struct tcf_gate *gact = to_gate(a);
465 	struct tcf_gate_params *p;
466 
467 	p = &gact->param;
468 	hrtimer_cancel(&gact->hitimer);
469 	release_entry_list(&p->entries);
470 }
471 
472 static int dumping_entry(struct sk_buff *skb,
473 			 struct tcfg_gate_entry *entry)
474 {
475 	struct nlattr *item;
476 
477 	item = nla_nest_start_noflag(skb, TCA_GATE_ONE_ENTRY);
478 	if (!item)
479 		return -ENOSPC;
480 
481 	if (nla_put_u32(skb, TCA_GATE_ENTRY_INDEX, entry->index))
482 		goto nla_put_failure;
483 
484 	if (entry->gate_state && nla_put_flag(skb, TCA_GATE_ENTRY_GATE))
485 		goto nla_put_failure;
486 
487 	if (nla_put_u32(skb, TCA_GATE_ENTRY_INTERVAL, entry->interval))
488 		goto nla_put_failure;
489 
490 	if (nla_put_s32(skb, TCA_GATE_ENTRY_MAX_OCTETS, entry->maxoctets))
491 		goto nla_put_failure;
492 
493 	if (nla_put_s32(skb, TCA_GATE_ENTRY_IPV, entry->ipv))
494 		goto nla_put_failure;
495 
496 	return nla_nest_end(skb, item);
497 
498 nla_put_failure:
499 	nla_nest_cancel(skb, item);
500 	return -1;
501 }
502 
503 static int tcf_gate_dump(struct sk_buff *skb, struct tc_action *a,
504 			 int bind, int ref)
505 {
506 	unsigned char *b = skb_tail_pointer(skb);
507 	struct tcf_gate *gact = to_gate(a);
508 	struct tc_gate opt = {
509 		.index    = gact->tcf_index,
510 		.refcnt   = refcount_read(&gact->tcf_refcnt) - ref,
511 		.bindcnt  = atomic_read(&gact->tcf_bindcnt) - bind,
512 	};
513 	struct tcfg_gate_entry *entry;
514 	struct tcf_gate_params *p;
515 	struct nlattr *entry_list;
516 	struct tcf_t t;
517 
518 	spin_lock_bh(&gact->tcf_lock);
519 	opt.action = gact->tcf_action;
520 
521 	p = &gact->param;
522 
523 	if (nla_put(skb, TCA_GATE_PARMS, sizeof(opt), &opt))
524 		goto nla_put_failure;
525 
526 	if (nla_put_u64_64bit(skb, TCA_GATE_BASE_TIME,
527 			      p->tcfg_basetime, TCA_GATE_PAD))
528 		goto nla_put_failure;
529 
530 	if (nla_put_u64_64bit(skb, TCA_GATE_CYCLE_TIME,
531 			      p->tcfg_cycletime, TCA_GATE_PAD))
532 		goto nla_put_failure;
533 
534 	if (nla_put_u64_64bit(skb, TCA_GATE_CYCLE_TIME_EXT,
535 			      p->tcfg_cycletime_ext, TCA_GATE_PAD))
536 		goto nla_put_failure;
537 
538 	if (nla_put_s32(skb, TCA_GATE_CLOCKID, p->tcfg_clockid))
539 		goto nla_put_failure;
540 
541 	if (nla_put_u32(skb, TCA_GATE_FLAGS, p->tcfg_flags))
542 		goto nla_put_failure;
543 
544 	if (nla_put_s32(skb, TCA_GATE_PRIORITY, p->tcfg_priority))
545 		goto nla_put_failure;
546 
547 	entry_list = nla_nest_start_noflag(skb, TCA_GATE_ENTRY_LIST);
548 	if (!entry_list)
549 		goto nla_put_failure;
550 
551 	list_for_each_entry(entry, &p->entries, list) {
552 		if (dumping_entry(skb, entry) < 0)
553 			goto nla_put_failure;
554 	}
555 
556 	nla_nest_end(skb, entry_list);
557 
558 	tcf_tm_dump(&t, &gact->tcf_tm);
559 	if (nla_put_64bit(skb, TCA_GATE_TM, sizeof(t), &t, TCA_GATE_PAD))
560 		goto nla_put_failure;
561 	spin_unlock_bh(&gact->tcf_lock);
562 
563 	return skb->len;
564 
565 nla_put_failure:
566 	spin_unlock_bh(&gact->tcf_lock);
567 	nlmsg_trim(skb, b);
568 	return -1;
569 }
570 
571 static void tcf_gate_stats_update(struct tc_action *a, u64 bytes, u64 packets,
572 				  u64 drops, u64 lastuse, bool hw)
573 {
574 	struct tcf_gate *gact = to_gate(a);
575 	struct tcf_t *tm = &gact->tcf_tm;
576 
577 	tcf_action_update_stats(a, bytes, packets, drops, hw);
578 	tm->lastuse = max_t(u64, tm->lastuse, lastuse);
579 }
580 
581 static size_t tcf_gate_get_fill_size(const struct tc_action *act)
582 {
583 	return nla_total_size(sizeof(struct tc_gate));
584 }
585 
586 static void tcf_gate_entry_destructor(void *priv)
587 {
588 	struct action_gate_entry *oe = priv;
589 
590 	kfree(oe);
591 }
592 
593 static int tcf_gate_get_entries(struct flow_action_entry *entry,
594 				const struct tc_action *act)
595 {
596 	entry->gate.entries = tcf_gate_get_list(act);
597 
598 	if (!entry->gate.entries)
599 		return -EINVAL;
600 
601 	entry->destructor = tcf_gate_entry_destructor;
602 	entry->destructor_priv = entry->gate.entries;
603 
604 	return 0;
605 }
606 
607 static int tcf_gate_offload_act_setup(struct tc_action *act, void *entry_data,
608 				      u32 *index_inc, bool bind,
609 				      struct netlink_ext_ack *extack)
610 {
611 	int err;
612 
613 	if (bind) {
614 		struct flow_action_entry *entry = entry_data;
615 
616 		entry->id = FLOW_ACTION_GATE;
617 		entry->gate.prio = tcf_gate_prio(act);
618 		entry->gate.basetime = tcf_gate_basetime(act);
619 		entry->gate.cycletime = tcf_gate_cycletime(act);
620 		entry->gate.cycletimeext = tcf_gate_cycletimeext(act);
621 		entry->gate.num_entries = tcf_gate_num_entries(act);
622 		err = tcf_gate_get_entries(entry, act);
623 		if (err)
624 			return err;
625 		*index_inc = 1;
626 	} else {
627 		struct flow_offload_action *fl_action = entry_data;
628 
629 		fl_action->id = FLOW_ACTION_GATE;
630 	}
631 
632 	return 0;
633 }
634 
635 static struct tc_action_ops act_gate_ops = {
636 	.kind		=	"gate",
637 	.id		=	TCA_ID_GATE,
638 	.owner		=	THIS_MODULE,
639 	.act		=	tcf_gate_act,
640 	.dump		=	tcf_gate_dump,
641 	.init		=	tcf_gate_init,
642 	.cleanup	=	tcf_gate_cleanup,
643 	.stats_update	=	tcf_gate_stats_update,
644 	.get_fill_size	=	tcf_gate_get_fill_size,
645 	.offload_act_setup =	tcf_gate_offload_act_setup,
646 	.size		=	sizeof(struct tcf_gate),
647 };
648 
649 static __net_init int gate_init_net(struct net *net)
650 {
651 	struct tc_action_net *tn = net_generic(net, act_gate_ops.net_id);
652 
653 	return tc_action_net_init(net, tn, &act_gate_ops);
654 }
655 
656 static void __net_exit gate_exit_net(struct list_head *net_list)
657 {
658 	tc_action_net_exit(net_list, act_gate_ops.net_id);
659 }
660 
661 static struct pernet_operations gate_net_ops = {
662 	.init = gate_init_net,
663 	.exit_batch = gate_exit_net,
664 	.id   = &act_gate_ops.net_id,
665 	.size = sizeof(struct tc_action_net),
666 };
667 
668 static int __init gate_init_module(void)
669 {
670 	return tcf_register_action(&act_gate_ops, &gate_net_ops);
671 }
672 
673 static void __exit gate_cleanup_module(void)
674 {
675 	tcf_unregister_action(&act_gate_ops, &gate_net_ops);
676 }
677 
678 module_init(gate_init_module);
679 module_exit(gate_cleanup_module);
680 MODULE_DESCRIPTION("TC gate action");
681 MODULE_LICENSE("GPL v2");
682