Linux 6.9-rc1
[linux-2.6-microblaze.git] / net / sched / act_gate.c
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 ACT_P_BOUND;
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 MODULE_ALIAS_NET_ACT("gate");
649
650 static __net_init int gate_init_net(struct net *net)
651 {
652         struct tc_action_net *tn = net_generic(net, act_gate_ops.net_id);
653
654         return tc_action_net_init(net, tn, &act_gate_ops);
655 }
656
657 static void __net_exit gate_exit_net(struct list_head *net_list)
658 {
659         tc_action_net_exit(net_list, act_gate_ops.net_id);
660 }
661
662 static struct pernet_operations gate_net_ops = {
663         .init = gate_init_net,
664         .exit_batch = gate_exit_net,
665         .id   = &act_gate_ops.net_id,
666         .size = sizeof(struct tc_action_net),
667 };
668
669 static int __init gate_init_module(void)
670 {
671         return tcf_register_action(&act_gate_ops, &gate_net_ops);
672 }
673
674 static void __exit gate_cleanup_module(void)
675 {
676         tcf_unregister_action(&act_gate_ops, &gate_net_ops);
677 }
678
679 module_init(gate_init_module);
680 module_exit(gate_cleanup_module);
681 MODULE_DESCRIPTION("TC gate action");
682 MODULE_LICENSE("GPL v2");