/home/lenb/src/to-linus branch 'acpi-2.6.12'
[linux-2.6] / net / ipv6 / ip6_flowlabel.c
1 /*
2  *      ip6_flowlabel.c         IPv6 flowlabel manager.
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  */
11
12 #include <linux/config.h>
13 #include <linux/errno.h>
14 #include <linux/types.h>
15 #include <linux/socket.h>
16 #include <linux/net.h>
17 #include <linux/netdevice.h>
18 #include <linux/if_arp.h>
19 #include <linux/in6.h>
20 #include <linux/route.h>
21 #include <linux/proc_fs.h>
22 #include <linux/seq_file.h>
23
24 #include <net/sock.h>
25
26 #include <net/ipv6.h>
27 #include <net/ndisc.h>
28 #include <net/protocol.h>
29 #include <net/ip6_route.h>
30 #include <net/addrconf.h>
31 #include <net/rawv6.h>
32 #include <net/icmp.h>
33 #include <net/transp_v6.h>
34
35 #include <asm/uaccess.h>
36
37 #define FL_MIN_LINGER   6       /* Minimal linger. It is set to 6sec specified
38                                    in old IPv6 RFC. Well, it was reasonable value.
39                                  */
40 #define FL_MAX_LINGER   60      /* Maximal linger timeout */
41
42 /* FL hash table */
43
44 #define FL_MAX_PER_SOCK 32
45 #define FL_MAX_SIZE     4096
46 #define FL_HASH_MASK    255
47 #define FL_HASH(l)      (ntohl(l)&FL_HASH_MASK)
48
49 static atomic_t fl_size = ATOMIC_INIT(0);
50 static struct ip6_flowlabel *fl_ht[FL_HASH_MASK+1];
51
52 static void ip6_fl_gc(unsigned long dummy);
53 static struct timer_list ip6_fl_gc_timer = TIMER_INITIALIZER(ip6_fl_gc, 0, 0);
54
55 /* FL hash table lock: it protects only of GC */
56
57 static DEFINE_RWLOCK(ip6_fl_lock);
58
59 /* Big socket sock */
60
61 static DEFINE_RWLOCK(ip6_sk_fl_lock);
62
63
64 static __inline__ struct ip6_flowlabel * __fl_lookup(u32 label)
65 {
66         struct ip6_flowlabel *fl;
67
68         for (fl=fl_ht[FL_HASH(label)]; fl; fl = fl->next) {
69                 if (fl->label == label)
70                         return fl;
71         }
72         return NULL;
73 }
74
75 static struct ip6_flowlabel * fl_lookup(u32 label)
76 {
77         struct ip6_flowlabel *fl;
78
79         read_lock_bh(&ip6_fl_lock);
80         fl = __fl_lookup(label);
81         if (fl)
82                 atomic_inc(&fl->users);
83         read_unlock_bh(&ip6_fl_lock);
84         return fl;
85 }
86
87
88 static void fl_free(struct ip6_flowlabel *fl)
89 {
90         if (fl)
91                 kfree(fl->opt);
92         kfree(fl);
93 }
94
95 static void fl_release(struct ip6_flowlabel *fl)
96 {
97         write_lock_bh(&ip6_fl_lock);
98
99         fl->lastuse = jiffies;
100         if (atomic_dec_and_test(&fl->users)) {
101                 unsigned long ttd = fl->lastuse + fl->linger;
102                 if (time_after(ttd, fl->expires))
103                         fl->expires = ttd;
104                 ttd = fl->expires;
105                 if (fl->opt && fl->share == IPV6_FL_S_EXCL) {
106                         struct ipv6_txoptions *opt = fl->opt;
107                         fl->opt = NULL;
108                         kfree(opt);
109                 }
110                 if (!timer_pending(&ip6_fl_gc_timer) ||
111                     time_after(ip6_fl_gc_timer.expires, ttd))
112                         mod_timer(&ip6_fl_gc_timer, ttd);
113         }
114
115         write_unlock_bh(&ip6_fl_lock);
116 }
117
118 static void ip6_fl_gc(unsigned long dummy)
119 {
120         int i;
121         unsigned long now = jiffies;
122         unsigned long sched = 0;
123
124         write_lock(&ip6_fl_lock);
125
126         for (i=0; i<=FL_HASH_MASK; i++) {
127                 struct ip6_flowlabel *fl, **flp;
128                 flp = &fl_ht[i];
129                 while ((fl=*flp) != NULL) {
130                         if (atomic_read(&fl->users) == 0) {
131                                 unsigned long ttd = fl->lastuse + fl->linger;
132                                 if (time_after(ttd, fl->expires))
133                                         fl->expires = ttd;
134                                 ttd = fl->expires;
135                                 if (time_after_eq(now, ttd)) {
136                                         *flp = fl->next;
137                                         fl_free(fl);
138                                         atomic_dec(&fl_size);
139                                         continue;
140                                 }
141                                 if (!sched || time_before(ttd, sched))
142                                         sched = ttd;
143                         }
144                         flp = &fl->next;
145                 }
146         }
147         if (!sched && atomic_read(&fl_size))
148                 sched = now + FL_MAX_LINGER;
149         if (sched) {
150                 ip6_fl_gc_timer.expires = sched;
151                 add_timer(&ip6_fl_gc_timer);
152         }
153         write_unlock(&ip6_fl_lock);
154 }
155
156 static int fl_intern(struct ip6_flowlabel *fl, __u32 label)
157 {
158         fl->label = label & IPV6_FLOWLABEL_MASK;
159
160         write_lock_bh(&ip6_fl_lock);
161         if (label == 0) {
162                 for (;;) {
163                         fl->label = htonl(net_random())&IPV6_FLOWLABEL_MASK;
164                         if (fl->label) {
165                                 struct ip6_flowlabel *lfl;
166                                 lfl = __fl_lookup(fl->label);
167                                 if (lfl == NULL)
168                                         break;
169                         }
170                 }
171         }
172
173         fl->lastuse = jiffies;
174         fl->next = fl_ht[FL_HASH(fl->label)];
175         fl_ht[FL_HASH(fl->label)] = fl;
176         atomic_inc(&fl_size);
177         write_unlock_bh(&ip6_fl_lock);
178         return 0;
179 }
180
181
182
183 /* Socket flowlabel lists */
184
185 struct ip6_flowlabel * fl6_sock_lookup(struct sock *sk, u32 label)
186 {
187         struct ipv6_fl_socklist *sfl;
188         struct ipv6_pinfo *np = inet6_sk(sk);
189
190         label &= IPV6_FLOWLABEL_MASK;
191
192         for (sfl=np->ipv6_fl_list; sfl; sfl = sfl->next) {
193                 struct ip6_flowlabel *fl = sfl->fl;
194                 if (fl->label == label) {
195                         fl->lastuse = jiffies;
196                         atomic_inc(&fl->users);
197                         return fl;
198                 }
199         }
200         return NULL;
201 }
202
203 void fl6_free_socklist(struct sock *sk)
204 {
205         struct ipv6_pinfo *np = inet6_sk(sk);
206         struct ipv6_fl_socklist *sfl;
207
208         while ((sfl = np->ipv6_fl_list) != NULL) {
209                 np->ipv6_fl_list = sfl->next;
210                 fl_release(sfl->fl);
211                 kfree(sfl);
212         }
213 }
214
215 /* Service routines */
216
217
218 /*
219    It is the only difficult place. flowlabel enforces equal headers
220    before and including routing header, however user may supply options
221    following rthdr.
222  */
223
224 struct ipv6_txoptions *fl6_merge_options(struct ipv6_txoptions * opt_space,
225                                          struct ip6_flowlabel * fl,
226                                          struct ipv6_txoptions * fopt)
227 {
228         struct ipv6_txoptions * fl_opt = fl->opt;
229
230         if (fopt == NULL || fopt->opt_flen == 0)
231                 return fl_opt;
232
233         if (fl_opt != NULL) {
234                 opt_space->hopopt = fl_opt->hopopt;
235                 opt_space->dst0opt = fl_opt->dst0opt;
236                 opt_space->srcrt = fl_opt->srcrt;
237                 opt_space->opt_nflen = fl_opt->opt_nflen;
238         } else {
239                 if (fopt->opt_nflen == 0)
240                         return fopt;
241                 opt_space->hopopt = NULL;
242                 opt_space->dst0opt = NULL;
243                 opt_space->srcrt = NULL;
244                 opt_space->opt_nflen = 0;
245         }
246         opt_space->dst1opt = fopt->dst1opt;
247         opt_space->opt_flen = fopt->opt_flen;
248         return opt_space;
249 }
250
251 static unsigned long check_linger(unsigned long ttl)
252 {
253         if (ttl < FL_MIN_LINGER)
254                 return FL_MIN_LINGER*HZ;
255         if (ttl > FL_MAX_LINGER && !capable(CAP_NET_ADMIN))
256                 return 0;
257         return ttl*HZ;
258 }
259
260 static int fl6_renew(struct ip6_flowlabel *fl, unsigned long linger, unsigned long expires)
261 {
262         linger = check_linger(linger);
263         if (!linger)
264                 return -EPERM;
265         expires = check_linger(expires);
266         if (!expires)
267                 return -EPERM;
268         fl->lastuse = jiffies;
269         if (time_before(fl->linger, linger))
270                 fl->linger = linger;
271         if (time_before(expires, fl->linger))
272                 expires = fl->linger;
273         if (time_before(fl->expires, fl->lastuse + expires))
274                 fl->expires = fl->lastuse + expires;
275         return 0;
276 }
277
278 static struct ip6_flowlabel *
279 fl_create(struct in6_flowlabel_req *freq, char __user *optval, int optlen, int *err_p)
280 {
281         struct ip6_flowlabel *fl;
282         int olen;
283         int addr_type;
284         int err;
285
286         err = -ENOMEM;
287         fl = kmalloc(sizeof(*fl), GFP_KERNEL);
288         if (fl == NULL)
289                 goto done;
290         memset(fl, 0, sizeof(*fl));
291
292         olen = optlen - CMSG_ALIGN(sizeof(*freq));
293         if (olen > 0) {
294                 struct msghdr msg;
295                 struct flowi flowi;
296                 int junk;
297
298                 err = -ENOMEM;
299                 fl->opt = kmalloc(sizeof(*fl->opt) + olen, GFP_KERNEL);
300                 if (fl->opt == NULL)
301                         goto done;
302
303                 memset(fl->opt, 0, sizeof(*fl->opt));
304                 fl->opt->tot_len = sizeof(*fl->opt) + olen;
305                 err = -EFAULT;
306                 if (copy_from_user(fl->opt+1, optval+CMSG_ALIGN(sizeof(*freq)), olen))
307                         goto done;
308
309                 msg.msg_controllen = olen;
310                 msg.msg_control = (void*)(fl->opt+1);
311                 flowi.oif = 0;
312
313                 err = datagram_send_ctl(&msg, &flowi, fl->opt, &junk);
314                 if (err)
315                         goto done;
316                 err = -EINVAL;
317                 if (fl->opt->opt_flen)
318                         goto done;
319                 if (fl->opt->opt_nflen == 0) {
320                         kfree(fl->opt);
321                         fl->opt = NULL;
322                 }
323         }
324
325         fl->expires = jiffies;
326         err = fl6_renew(fl, freq->flr_linger, freq->flr_expires);
327         if (err)
328                 goto done;
329         fl->share = freq->flr_share;
330         addr_type = ipv6_addr_type(&freq->flr_dst);
331         if ((addr_type&IPV6_ADDR_MAPPED)
332             || addr_type == IPV6_ADDR_ANY)
333                 goto done;
334         ipv6_addr_copy(&fl->dst, &freq->flr_dst);
335         atomic_set(&fl->users, 1);
336         switch (fl->share) {
337         case IPV6_FL_S_EXCL:
338         case IPV6_FL_S_ANY:
339                 break;
340         case IPV6_FL_S_PROCESS:
341                 fl->owner = current->pid;
342                 break;
343         case IPV6_FL_S_USER:
344                 fl->owner = current->euid;
345                 break;
346         default:
347                 err = -EINVAL;
348                 goto done;
349         }
350         return fl;
351
352 done:
353         fl_free(fl);
354         *err_p = err;
355         return NULL;
356 }
357
358 static int mem_check(struct sock *sk)
359 {
360         struct ipv6_pinfo *np = inet6_sk(sk);
361         struct ipv6_fl_socklist *sfl;
362         int room = FL_MAX_SIZE - atomic_read(&fl_size);
363         int count = 0;
364
365         if (room > FL_MAX_SIZE - FL_MAX_PER_SOCK)
366                 return 0;
367
368         for (sfl = np->ipv6_fl_list; sfl; sfl = sfl->next)
369                 count++;
370
371         if (room <= 0 ||
372             ((count >= FL_MAX_PER_SOCK ||
373              (count > 0 && room < FL_MAX_SIZE/2) || room < FL_MAX_SIZE/4)
374              && !capable(CAP_NET_ADMIN)))
375                 return -ENOBUFS;
376
377         return 0;
378 }
379
380 static int ipv6_hdr_cmp(struct ipv6_opt_hdr *h1, struct ipv6_opt_hdr *h2)
381 {
382         if (h1 == h2)
383                 return 0;
384         if (h1 == NULL || h2 == NULL)
385                 return 1;
386         if (h1->hdrlen != h2->hdrlen)
387                 return 1;
388         return memcmp(h1+1, h2+1, ((h1->hdrlen+1)<<3) - sizeof(*h1));
389 }
390
391 static int ipv6_opt_cmp(struct ipv6_txoptions *o1, struct ipv6_txoptions *o2)
392 {
393         if (o1 == o2)
394                 return 0;
395         if (o1 == NULL || o2 == NULL)
396                 return 1;
397         if (o1->opt_nflen != o2->opt_nflen)
398                 return 1;
399         if (ipv6_hdr_cmp(o1->hopopt, o2->hopopt))
400                 return 1;
401         if (ipv6_hdr_cmp(o1->dst0opt, o2->dst0opt))
402                 return 1;
403         if (ipv6_hdr_cmp((struct ipv6_opt_hdr *)o1->srcrt, (struct ipv6_opt_hdr *)o2->srcrt))
404                 return 1;
405         return 0;
406 }
407
408 int ipv6_flowlabel_opt(struct sock *sk, char __user *optval, int optlen)
409 {
410         int err;
411         struct ipv6_pinfo *np = inet6_sk(sk);
412         struct in6_flowlabel_req freq;
413         struct ipv6_fl_socklist *sfl1=NULL;
414         struct ipv6_fl_socklist *sfl, **sflp;
415         struct ip6_flowlabel *fl;
416
417         if (optlen < sizeof(freq))
418                 return -EINVAL;
419
420         if (copy_from_user(&freq, optval, sizeof(freq)))
421                 return -EFAULT;
422
423         switch (freq.flr_action) {
424         case IPV6_FL_A_PUT:
425                 write_lock_bh(&ip6_sk_fl_lock);
426                 for (sflp = &np->ipv6_fl_list; (sfl=*sflp)!=NULL; sflp = &sfl->next) {
427                         if (sfl->fl->label == freq.flr_label) {
428                                 if (freq.flr_label == (np->flow_label&IPV6_FLOWLABEL_MASK))
429                                         np->flow_label &= ~IPV6_FLOWLABEL_MASK;
430                                 *sflp = sfl->next;
431                                 write_unlock_bh(&ip6_sk_fl_lock);
432                                 fl_release(sfl->fl);
433                                 kfree(sfl);
434                                 return 0;
435                         }
436                 }
437                 write_unlock_bh(&ip6_sk_fl_lock);
438                 return -ESRCH;
439
440         case IPV6_FL_A_RENEW:
441                 read_lock_bh(&ip6_sk_fl_lock);
442                 for (sfl = np->ipv6_fl_list; sfl; sfl = sfl->next) {
443                         if (sfl->fl->label == freq.flr_label) {
444                                 err = fl6_renew(sfl->fl, freq.flr_linger, freq.flr_expires);
445                                 read_unlock_bh(&ip6_sk_fl_lock);
446                                 return err;
447                         }
448                 }
449                 read_unlock_bh(&ip6_sk_fl_lock);
450
451                 if (freq.flr_share == IPV6_FL_S_NONE && capable(CAP_NET_ADMIN)) {
452                         fl = fl_lookup(freq.flr_label);
453                         if (fl) {
454                                 err = fl6_renew(fl, freq.flr_linger, freq.flr_expires);
455                                 fl_release(fl);
456                                 return err;
457                         }
458                 }
459                 return -ESRCH;
460
461         case IPV6_FL_A_GET:
462                 if (freq.flr_label & ~IPV6_FLOWLABEL_MASK)
463                         return -EINVAL;
464
465                 fl = fl_create(&freq, optval, optlen, &err);
466                 if (fl == NULL)
467                         return err;
468                 sfl1 = kmalloc(sizeof(*sfl1), GFP_KERNEL);
469
470                 if (freq.flr_label) {
471                         struct ip6_flowlabel *fl1 = NULL;
472
473                         err = -EEXIST;
474                         read_lock_bh(&ip6_sk_fl_lock);
475                         for (sfl = np->ipv6_fl_list; sfl; sfl = sfl->next) {
476                                 if (sfl->fl->label == freq.flr_label) {
477                                         if (freq.flr_flags&IPV6_FL_F_EXCL) {
478                                                 read_unlock_bh(&ip6_sk_fl_lock);
479                                                 goto done;
480                                         }
481                                         fl1 = sfl->fl;
482                                         atomic_inc(&fl->users);
483                                         break;
484                                 }
485                         }
486                         read_unlock_bh(&ip6_sk_fl_lock);
487
488                         if (fl1 == NULL)
489                                 fl1 = fl_lookup(freq.flr_label);
490                         if (fl1) {
491                                 err = -EEXIST;
492                                 if (freq.flr_flags&IPV6_FL_F_EXCL)
493                                         goto release;
494                                 err = -EPERM;
495                                 if (fl1->share == IPV6_FL_S_EXCL ||
496                                     fl1->share != fl->share ||
497                                     fl1->owner != fl->owner)
498                                         goto release;
499
500                                 err = -EINVAL;
501                                 if (!ipv6_addr_equal(&fl1->dst, &fl->dst) ||
502                                     ipv6_opt_cmp(fl1->opt, fl->opt))
503                                         goto release;
504
505                                 err = -ENOMEM;
506                                 if (sfl1 == NULL)
507                                         goto release;
508                                 if (fl->linger > fl1->linger)
509                                         fl1->linger = fl->linger;
510                                 if ((long)(fl->expires - fl1->expires) > 0)
511                                         fl1->expires = fl->expires;
512                                 write_lock_bh(&ip6_sk_fl_lock);
513                                 sfl1->fl = fl1;
514                                 sfl1->next = np->ipv6_fl_list;
515                                 np->ipv6_fl_list = sfl1;
516                                 write_unlock_bh(&ip6_sk_fl_lock);
517                                 fl_free(fl);
518                                 return 0;
519
520 release:
521                                 fl_release(fl1);
522                                 goto done;
523                         }
524                 }
525                 err = -ENOENT;
526                 if (!(freq.flr_flags&IPV6_FL_F_CREATE))
527                         goto done;
528
529                 err = -ENOMEM;
530                 if (sfl1 == NULL || (err = mem_check(sk)) != 0)
531                         goto done;
532
533                 err = fl_intern(fl, freq.flr_label);
534                 if (err)
535                         goto done;
536
537                 if (!freq.flr_label) {
538                         if (copy_to_user(&((struct in6_flowlabel_req __user *) optval)->flr_label,
539                                          &fl->label, sizeof(fl->label))) {
540                                 /* Intentionally ignore fault. */
541                         }
542                 }
543
544                 sfl1->fl = fl;
545                 sfl1->next = np->ipv6_fl_list;
546                 np->ipv6_fl_list = sfl1;
547                 return 0;
548
549         default:
550                 return -EINVAL;
551         }
552
553 done:
554         fl_free(fl);
555         kfree(sfl1);
556         return err;
557 }
558
559 #ifdef CONFIG_PROC_FS
560
561 struct ip6fl_iter_state {
562         int bucket;
563 };
564
565 #define ip6fl_seq_private(seq)  ((struct ip6fl_iter_state *)(seq)->private)
566
567 static struct ip6_flowlabel *ip6fl_get_first(struct seq_file *seq)
568 {
569         struct ip6_flowlabel *fl = NULL;
570         struct ip6fl_iter_state *state = ip6fl_seq_private(seq);
571
572         for (state->bucket = 0; state->bucket <= FL_HASH_MASK; ++state->bucket) {
573                 if (fl_ht[state->bucket]) {
574                         fl = fl_ht[state->bucket];
575                         break;
576                 }
577         }
578         return fl;
579 }
580
581 static struct ip6_flowlabel *ip6fl_get_next(struct seq_file *seq, struct ip6_flowlabel *fl)
582 {
583         struct ip6fl_iter_state *state = ip6fl_seq_private(seq);
584
585         fl = fl->next;
586         while (!fl) {
587                 if (++state->bucket <= FL_HASH_MASK)
588                         fl = fl_ht[state->bucket];
589         }
590         return fl;
591 }
592
593 static struct ip6_flowlabel *ip6fl_get_idx(struct seq_file *seq, loff_t pos)
594 {
595         struct ip6_flowlabel *fl = ip6fl_get_first(seq);
596         if (fl)
597                 while (pos && (fl = ip6fl_get_next(seq, fl)) != NULL)
598                         --pos;
599         return pos ? NULL : fl;
600 }
601
602 static void *ip6fl_seq_start(struct seq_file *seq, loff_t *pos)
603 {
604         read_lock_bh(&ip6_fl_lock);
605         return *pos ? ip6fl_get_idx(seq, *pos - 1) : SEQ_START_TOKEN;
606 }
607
608 static void *ip6fl_seq_next(struct seq_file *seq, void *v, loff_t *pos)
609 {
610         struct ip6_flowlabel *fl;
611
612         if (v == SEQ_START_TOKEN)
613                 fl = ip6fl_get_first(seq);
614         else
615                 fl = ip6fl_get_next(seq, v);
616         ++*pos;
617         return fl;
618 }
619
620 static void ip6fl_seq_stop(struct seq_file *seq, void *v)
621 {
622         read_unlock_bh(&ip6_fl_lock);
623 }
624
625 static void ip6fl_fl_seq_show(struct seq_file *seq, struct ip6_flowlabel *fl)
626 {
627         while(fl) {
628                 seq_printf(seq,
629                            "%05X %-1d %-6d %-6d %-6ld %-8ld "
630                            "%02x%02x%02x%02x%02x%02x%02x%02x "
631                            "%-4d\n",
632                            (unsigned)ntohl(fl->label),
633                            fl->share,
634                            (unsigned)fl->owner,
635                            atomic_read(&fl->users),
636                            fl->linger/HZ,
637                            (long)(fl->expires - jiffies)/HZ,
638                            NIP6(fl->dst),
639                            fl->opt ? fl->opt->opt_nflen : 0);
640                 fl = fl->next;
641         }
642 }
643
644 static int ip6fl_seq_show(struct seq_file *seq, void *v)
645 {
646         if (v == SEQ_START_TOKEN)
647                 seq_puts(seq, "Label S Owner  Users  Linger Expires  "
648                               "Dst                              Opt\n");
649         else
650                 ip6fl_fl_seq_show(seq, v);
651         return 0;
652 }
653
654 static struct seq_operations ip6fl_seq_ops = {
655         .start  =       ip6fl_seq_start,
656         .next   =       ip6fl_seq_next,
657         .stop   =       ip6fl_seq_stop,
658         .show   =       ip6fl_seq_show,
659 };
660
661 static int ip6fl_seq_open(struct inode *inode, struct file *file)
662 {
663         struct seq_file *seq;
664         int rc = -ENOMEM;
665         struct ip6fl_iter_state *s = kmalloc(sizeof(*s), GFP_KERNEL);
666
667         if (!s)
668                 goto out;
669
670         rc = seq_open(file, &ip6fl_seq_ops);
671         if (rc)
672                 goto out_kfree;
673
674         seq = file->private_data;
675         seq->private = s;
676         memset(s, 0, sizeof(*s));
677 out:
678         return rc;
679 out_kfree:
680         kfree(s);
681         goto out;
682 }
683
684 static struct file_operations ip6fl_seq_fops = {
685         .owner          =       THIS_MODULE,
686         .open           =       ip6fl_seq_open,
687         .read           =       seq_read,
688         .llseek         =       seq_lseek,
689         .release        =       seq_release_private,
690 };
691 #endif
692
693
694 void ip6_flowlabel_init(void)
695 {
696 #ifdef CONFIG_PROC_FS
697         proc_net_fops_create("ip6_flowlabel", S_IRUGO, &ip6fl_seq_fops);
698 #endif
699 }
700
701 void ip6_flowlabel_cleanup(void)
702 {
703         del_timer(&ip6_fl_gc_timer);
704 #ifdef CONFIG_PROC_FS
705         proc_net_remove("ip6_flowlabel");
706 #endif
707 }