Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/x86/linux...
[linux-2.6] / net / ipv6 / ip6_fib.c
1 /*
2  *      Linux INET6 implementation
3  *      Forwarding Information Database
4  *
5  *      Authors:
6  *      Pedro Roque             <roque@di.fc.ul.pt>
7  *
8  *      $Id: ip6_fib.c,v 1.25 2001/10/31 21:55:55 davem Exp $
9  *
10  *      This program is free software; you can redistribute it and/or
11  *      modify it under the terms of the GNU General Public License
12  *      as published by the Free Software Foundation; either version
13  *      2 of the License, or (at your option) any later version.
14  */
15
16 /*
17  *      Changes:
18  *      Yuji SEKIYA @USAGI:     Support default route on router node;
19  *                              remove ip6_null_entry from the top of
20  *                              routing table.
21  *      Ville Nuorvala:         Fixed routing subtrees.
22  */
23 #include <linux/errno.h>
24 #include <linux/types.h>
25 #include <linux/net.h>
26 #include <linux/route.h>
27 #include <linux/netdevice.h>
28 #include <linux/in6.h>
29 #include <linux/init.h>
30 #include <linux/list.h>
31
32 #ifdef  CONFIG_PROC_FS
33 #include <linux/proc_fs.h>
34 #endif
35
36 #include <net/ipv6.h>
37 #include <net/ndisc.h>
38 #include <net/addrconf.h>
39
40 #include <net/ip6_fib.h>
41 #include <net/ip6_route.h>
42
43 #define RT6_DEBUG 2
44
45 #if RT6_DEBUG >= 3
46 #define RT6_TRACE(x...) printk(KERN_DEBUG x)
47 #else
48 #define RT6_TRACE(x...) do { ; } while (0)
49 #endif
50
51 static struct kmem_cache * fib6_node_kmem __read_mostly;
52
53 enum fib_walk_state_t
54 {
55 #ifdef CONFIG_IPV6_SUBTREES
56         FWS_S,
57 #endif
58         FWS_L,
59         FWS_R,
60         FWS_C,
61         FWS_U
62 };
63
64 struct fib6_cleaner_t
65 {
66         struct fib6_walker_t w;
67         struct net *net;
68         int (*func)(struct rt6_info *, void *arg);
69         void *arg;
70 };
71
72 static DEFINE_RWLOCK(fib6_walker_lock);
73
74 #ifdef CONFIG_IPV6_SUBTREES
75 #define FWS_INIT FWS_S
76 #else
77 #define FWS_INIT FWS_L
78 #endif
79
80 static void fib6_prune_clones(struct net *net, struct fib6_node *fn,
81                               struct rt6_info *rt);
82 static struct rt6_info *fib6_find_prefix(struct net *net, struct fib6_node *fn);
83 static struct fib6_node *fib6_repair_tree(struct net *net, struct fib6_node *fn);
84 static int fib6_walk(struct fib6_walker_t *w);
85 static int fib6_walk_continue(struct fib6_walker_t *w);
86
87 /*
88  *      A routing update causes an increase of the serial number on the
89  *      affected subtree. This allows for cached routes to be asynchronously
90  *      tested when modifications are made to the destination cache as a
91  *      result of redirects, path MTU changes, etc.
92  */
93
94 static __u32 rt_sernum;
95
96 static void fib6_gc_timer_cb(unsigned long arg);
97
98 static struct fib6_walker_t fib6_walker_list = {
99         .prev   = &fib6_walker_list,
100         .next   = &fib6_walker_list,
101 };
102
103 #define FOR_WALKERS(w) for ((w)=fib6_walker_list.next; (w) != &fib6_walker_list; (w)=(w)->next)
104
105 static inline void fib6_walker_link(struct fib6_walker_t *w)
106 {
107         write_lock_bh(&fib6_walker_lock);
108         w->next = fib6_walker_list.next;
109         w->prev = &fib6_walker_list;
110         w->next->prev = w;
111         w->prev->next = w;
112         write_unlock_bh(&fib6_walker_lock);
113 }
114
115 static inline void fib6_walker_unlink(struct fib6_walker_t *w)
116 {
117         write_lock_bh(&fib6_walker_lock);
118         w->next->prev = w->prev;
119         w->prev->next = w->next;
120         w->prev = w->next = w;
121         write_unlock_bh(&fib6_walker_lock);
122 }
123 static __inline__ u32 fib6_new_sernum(void)
124 {
125         u32 n = ++rt_sernum;
126         if ((__s32)n <= 0)
127                 rt_sernum = n = 1;
128         return n;
129 }
130
131 /*
132  *      Auxiliary address test functions for the radix tree.
133  *
134  *      These assume a 32bit processor (although it will work on
135  *      64bit processors)
136  */
137
138 /*
139  *      test bit
140  */
141
142 static __inline__ __be32 addr_bit_set(void *token, int fn_bit)
143 {
144         __be32 *addr = token;
145
146         return htonl(1 << ((~fn_bit)&0x1F)) & addr[fn_bit>>5];
147 }
148
149 static __inline__ struct fib6_node * node_alloc(void)
150 {
151         struct fib6_node *fn;
152
153         fn = kmem_cache_zalloc(fib6_node_kmem, GFP_ATOMIC);
154
155         return fn;
156 }
157
158 static __inline__ void node_free(struct fib6_node * fn)
159 {
160         kmem_cache_free(fib6_node_kmem, fn);
161 }
162
163 static __inline__ void rt6_release(struct rt6_info *rt)
164 {
165         if (atomic_dec_and_test(&rt->rt6i_ref))
166                 dst_free(&rt->u.dst);
167 }
168
169 #ifdef CONFIG_IPV6_MULTIPLE_TABLES
170 #define FIB_TABLE_HASHSZ 256
171 #else
172 #define FIB_TABLE_HASHSZ 1
173 #endif
174
175 static void fib6_link_table(struct net *net, struct fib6_table *tb)
176 {
177         unsigned int h;
178
179         /*
180          * Initialize table lock at a single place to give lockdep a key,
181          * tables aren't visible prior to being linked to the list.
182          */
183         rwlock_init(&tb->tb6_lock);
184
185         h = tb->tb6_id & (FIB_TABLE_HASHSZ - 1);
186
187         /*
188          * No protection necessary, this is the only list mutatation
189          * operation, tables never disappear once they exist.
190          */
191         hlist_add_head_rcu(&tb->tb6_hlist, &net->ipv6.fib_table_hash[h]);
192 }
193
194 #ifdef CONFIG_IPV6_MULTIPLE_TABLES
195
196 static struct fib6_table *fib6_alloc_table(struct net *net, u32 id)
197 {
198         struct fib6_table *table;
199
200         table = kzalloc(sizeof(*table), GFP_ATOMIC);
201         if (table != NULL) {
202                 table->tb6_id = id;
203                 table->tb6_root.leaf = net->ipv6.ip6_null_entry;
204                 table->tb6_root.fn_flags = RTN_ROOT | RTN_TL_ROOT | RTN_RTINFO;
205         }
206
207         return table;
208 }
209
210 struct fib6_table *fib6_new_table(struct net *net, u32 id)
211 {
212         struct fib6_table *tb;
213
214         if (id == 0)
215                 id = RT6_TABLE_MAIN;
216         tb = fib6_get_table(net, id);
217         if (tb)
218                 return tb;
219
220         tb = fib6_alloc_table(net, id);
221         if (tb != NULL)
222                 fib6_link_table(net, tb);
223
224         return tb;
225 }
226
227 struct fib6_table *fib6_get_table(struct net *net, u32 id)
228 {
229         struct fib6_table *tb;
230         struct hlist_head *head;
231         struct hlist_node *node;
232         unsigned int h;
233
234         if (id == 0)
235                 id = RT6_TABLE_MAIN;
236         h = id & (FIB_TABLE_HASHSZ - 1);
237         rcu_read_lock();
238         head = &net->ipv6.fib_table_hash[h];
239         hlist_for_each_entry_rcu(tb, node, head, tb6_hlist) {
240                 if (tb->tb6_id == id) {
241                         rcu_read_unlock();
242                         return tb;
243                 }
244         }
245         rcu_read_unlock();
246
247         return NULL;
248 }
249
250 static void fib6_tables_init(struct net *net)
251 {
252         fib6_link_table(net, net->ipv6.fib6_main_tbl);
253         fib6_link_table(net, net->ipv6.fib6_local_tbl);
254 }
255 #else
256
257 struct fib6_table *fib6_new_table(struct net *net, u32 id)
258 {
259         return fib6_get_table(net, id);
260 }
261
262 struct fib6_table *fib6_get_table(struct net *net, u32 id)
263 {
264           return net->ipv6.fib6_main_tbl;
265 }
266
267 struct dst_entry *fib6_rule_lookup(struct net *net, struct flowi *fl,
268                                    int flags, pol_lookup_t lookup)
269 {
270         return (struct dst_entry *) lookup(net, net->ipv6.fib6_main_tbl, fl, flags);
271 }
272
273 static void fib6_tables_init(struct net *net)
274 {
275         fib6_link_table(net, net->ipv6.fib6_main_tbl);
276 }
277
278 #endif
279
280 static int fib6_dump_node(struct fib6_walker_t *w)
281 {
282         int res;
283         struct rt6_info *rt;
284
285         for (rt = w->leaf; rt; rt = rt->u.dst.rt6_next) {
286                 res = rt6_dump_route(rt, w->args);
287                 if (res < 0) {
288                         /* Frame is full, suspend walking */
289                         w->leaf = rt;
290                         return 1;
291                 }
292                 BUG_TRAP(res!=0);
293         }
294         w->leaf = NULL;
295         return 0;
296 }
297
298 static void fib6_dump_end(struct netlink_callback *cb)
299 {
300         struct fib6_walker_t *w = (void*)cb->args[2];
301
302         if (w) {
303                 cb->args[2] = 0;
304                 kfree(w);
305         }
306         cb->done = (void*)cb->args[3];
307         cb->args[1] = 3;
308 }
309
310 static int fib6_dump_done(struct netlink_callback *cb)
311 {
312         fib6_dump_end(cb);
313         return cb->done ? cb->done(cb) : 0;
314 }
315
316 static int fib6_dump_table(struct fib6_table *table, struct sk_buff *skb,
317                            struct netlink_callback *cb)
318 {
319         struct fib6_walker_t *w;
320         int res;
321
322         w = (void *)cb->args[2];
323         w->root = &table->tb6_root;
324
325         if (cb->args[4] == 0) {
326                 read_lock_bh(&table->tb6_lock);
327                 res = fib6_walk(w);
328                 read_unlock_bh(&table->tb6_lock);
329                 if (res > 0)
330                         cb->args[4] = 1;
331         } else {
332                 read_lock_bh(&table->tb6_lock);
333                 res = fib6_walk_continue(w);
334                 read_unlock_bh(&table->tb6_lock);
335                 if (res != 0) {
336                         if (res < 0)
337                                 fib6_walker_unlink(w);
338                         goto end;
339                 }
340                 fib6_walker_unlink(w);
341                 cb->args[4] = 0;
342         }
343 end:
344         return res;
345 }
346
347 static int inet6_dump_fib(struct sk_buff *skb, struct netlink_callback *cb)
348 {
349         struct net *net = sock_net(skb->sk);
350         unsigned int h, s_h;
351         unsigned int e = 0, s_e;
352         struct rt6_rtnl_dump_arg arg;
353         struct fib6_walker_t *w;
354         struct fib6_table *tb;
355         struct hlist_node *node;
356         struct hlist_head *head;
357         int res = 0;
358
359         s_h = cb->args[0];
360         s_e = cb->args[1];
361
362         w = (void *)cb->args[2];
363         if (w == NULL) {
364                 /* New dump:
365                  *
366                  * 1. hook callback destructor.
367                  */
368                 cb->args[3] = (long)cb->done;
369                 cb->done = fib6_dump_done;
370
371                 /*
372                  * 2. allocate and initialize walker.
373                  */
374                 w = kzalloc(sizeof(*w), GFP_ATOMIC);
375                 if (w == NULL)
376                         return -ENOMEM;
377                 w->func = fib6_dump_node;
378                 cb->args[2] = (long)w;
379         }
380
381         arg.skb = skb;
382         arg.cb = cb;
383         w->args = &arg;
384
385         for (h = s_h; h < FIB_TABLE_HASHSZ; h++, s_e = 0) {
386                 e = 0;
387                 head = &net->ipv6.fib_table_hash[h];
388                 hlist_for_each_entry(tb, node, head, tb6_hlist) {
389                         if (e < s_e)
390                                 goto next;
391                         res = fib6_dump_table(tb, skb, cb);
392                         if (res != 0)
393                                 goto out;
394 next:
395                         e++;
396                 }
397         }
398 out:
399         cb->args[1] = e;
400         cb->args[0] = h;
401
402         res = res < 0 ? res : skb->len;
403         if (res <= 0)
404                 fib6_dump_end(cb);
405         return res;
406 }
407
408 /*
409  *      Routing Table
410  *
411  *      return the appropriate node for a routing tree "add" operation
412  *      by either creating and inserting or by returning an existing
413  *      node.
414  */
415
416 static struct fib6_node * fib6_add_1(struct fib6_node *root, void *addr,
417                                      int addrlen, int plen,
418                                      int offset)
419 {
420         struct fib6_node *fn, *in, *ln;
421         struct fib6_node *pn = NULL;
422         struct rt6key *key;
423         int     bit;
424         __be32  dir = 0;
425         __u32   sernum = fib6_new_sernum();
426
427         RT6_TRACE("fib6_add_1\n");
428
429         /* insert node in tree */
430
431         fn = root;
432
433         do {
434                 key = (struct rt6key *)((u8 *)fn->leaf + offset);
435
436                 /*
437                  *      Prefix match
438                  */
439                 if (plen < fn->fn_bit ||
440                     !ipv6_prefix_equal(&key->addr, addr, fn->fn_bit))
441                         goto insert_above;
442
443                 /*
444                  *      Exact match ?
445                  */
446
447                 if (plen == fn->fn_bit) {
448                         /* clean up an intermediate node */
449                         if ((fn->fn_flags & RTN_RTINFO) == 0) {
450                                 rt6_release(fn->leaf);
451                                 fn->leaf = NULL;
452                         }
453
454                         fn->fn_sernum = sernum;
455
456                         return fn;
457                 }
458
459                 /*
460                  *      We have more bits to go
461                  */
462
463                 /* Try to walk down on tree. */
464                 fn->fn_sernum = sernum;
465                 dir = addr_bit_set(addr, fn->fn_bit);
466                 pn = fn;
467                 fn = dir ? fn->right: fn->left;
468         } while (fn);
469
470         /*
471          *      We walked to the bottom of tree.
472          *      Create new leaf node without children.
473          */
474
475         ln = node_alloc();
476
477         if (ln == NULL)
478                 return NULL;
479         ln->fn_bit = plen;
480
481         ln->parent = pn;
482         ln->fn_sernum = sernum;
483
484         if (dir)
485                 pn->right = ln;
486         else
487                 pn->left  = ln;
488
489         return ln;
490
491
492 insert_above:
493         /*
494          * split since we don't have a common prefix anymore or
495          * we have a less significant route.
496          * we've to insert an intermediate node on the list
497          * this new node will point to the one we need to create
498          * and the current
499          */
500
501         pn = fn->parent;
502
503         /* find 1st bit in difference between the 2 addrs.
504
505            See comment in __ipv6_addr_diff: bit may be an invalid value,
506            but if it is >= plen, the value is ignored in any case.
507          */
508
509         bit = __ipv6_addr_diff(addr, &key->addr, addrlen);
510
511         /*
512          *              (intermediate)[in]
513          *                /        \
514          *      (new leaf node)[ln] (old node)[fn]
515          */
516         if (plen > bit) {
517                 in = node_alloc();
518                 ln = node_alloc();
519
520                 if (in == NULL || ln == NULL) {
521                         if (in)
522                                 node_free(in);
523                         if (ln)
524                                 node_free(ln);
525                         return NULL;
526                 }
527
528                 /*
529                  * new intermediate node.
530                  * RTN_RTINFO will
531                  * be off since that an address that chooses one of
532                  * the branches would not match less specific routes
533                  * in the other branch
534                  */
535
536                 in->fn_bit = bit;
537
538                 in->parent = pn;
539                 in->leaf = fn->leaf;
540                 atomic_inc(&in->leaf->rt6i_ref);
541
542                 in->fn_sernum = sernum;
543
544                 /* update parent pointer */
545                 if (dir)
546                         pn->right = in;
547                 else
548                         pn->left  = in;
549
550                 ln->fn_bit = plen;
551
552                 ln->parent = in;
553                 fn->parent = in;
554
555                 ln->fn_sernum = sernum;
556
557                 if (addr_bit_set(addr, bit)) {
558                         in->right = ln;
559                         in->left  = fn;
560                 } else {
561                         in->left  = ln;
562                         in->right = fn;
563                 }
564         } else { /* plen <= bit */
565
566                 /*
567                  *              (new leaf node)[ln]
568                  *                /        \
569                  *           (old node)[fn] NULL
570                  */
571
572                 ln = node_alloc();
573
574                 if (ln == NULL)
575                         return NULL;
576
577                 ln->fn_bit = plen;
578
579                 ln->parent = pn;
580
581                 ln->fn_sernum = sernum;
582
583                 if (dir)
584                         pn->right = ln;
585                 else
586                         pn->left  = ln;
587
588                 if (addr_bit_set(&key->addr, plen))
589                         ln->right = fn;
590                 else
591                         ln->left  = fn;
592
593                 fn->parent = ln;
594         }
595         return ln;
596 }
597
598 /*
599  *      Insert routing information in a node.
600  */
601
602 static int fib6_add_rt2node(struct fib6_node *fn, struct rt6_info *rt,
603                             struct nl_info *info)
604 {
605         struct rt6_info *iter = NULL;
606         struct rt6_info **ins;
607
608         ins = &fn->leaf;
609
610         for (iter = fn->leaf; iter; iter=iter->u.dst.rt6_next) {
611                 /*
612                  *      Search for duplicates
613                  */
614
615                 if (iter->rt6i_metric == rt->rt6i_metric) {
616                         /*
617                          *      Same priority level
618                          */
619
620                         if (iter->rt6i_dev == rt->rt6i_dev &&
621                             iter->rt6i_idev == rt->rt6i_idev &&
622                             ipv6_addr_equal(&iter->rt6i_gateway,
623                                             &rt->rt6i_gateway)) {
624                                 if (!(iter->rt6i_flags&RTF_EXPIRES))
625                                         return -EEXIST;
626                                 iter->rt6i_expires = rt->rt6i_expires;
627                                 if (!(rt->rt6i_flags&RTF_EXPIRES)) {
628                                         iter->rt6i_flags &= ~RTF_EXPIRES;
629                                         iter->rt6i_expires = 0;
630                                 }
631                                 return -EEXIST;
632                         }
633                 }
634
635                 if (iter->rt6i_metric > rt->rt6i_metric)
636                         break;
637
638                 ins = &iter->u.dst.rt6_next;
639         }
640
641         /* Reset round-robin state, if necessary */
642         if (ins == &fn->leaf)
643                 fn->rr_ptr = NULL;
644
645         /*
646          *      insert node
647          */
648
649         rt->u.dst.rt6_next = iter;
650         *ins = rt;
651         rt->rt6i_node = fn;
652         atomic_inc(&rt->rt6i_ref);
653         inet6_rt_notify(RTM_NEWROUTE, rt, info);
654         info->nl_net->ipv6.rt6_stats->fib_rt_entries++;
655
656         if ((fn->fn_flags & RTN_RTINFO) == 0) {
657                 info->nl_net->ipv6.rt6_stats->fib_route_nodes++;
658                 fn->fn_flags |= RTN_RTINFO;
659         }
660
661         return 0;
662 }
663
664 static __inline__ void fib6_start_gc(struct net *net, struct rt6_info *rt)
665 {
666         if (net->ipv6.ip6_fib_timer->expires == 0 &&
667             (rt->rt6i_flags & (RTF_EXPIRES|RTF_CACHE)))
668                 mod_timer(net->ipv6.ip6_fib_timer, jiffies +
669                           net->ipv6.sysctl.ip6_rt_gc_interval);
670 }
671
672 void fib6_force_start_gc(struct net *net)
673 {
674         if (net->ipv6.ip6_fib_timer->expires == 0)
675                 mod_timer(net->ipv6.ip6_fib_timer, jiffies +
676                           net->ipv6.sysctl.ip6_rt_gc_interval);
677 }
678
679 /*
680  *      Add routing information to the routing tree.
681  *      <destination addr>/<source addr>
682  *      with source addr info in sub-trees
683  */
684
685 int fib6_add(struct fib6_node *root, struct rt6_info *rt, struct nl_info *info)
686 {
687         struct fib6_node *fn, *pn = NULL;
688         int err = -ENOMEM;
689
690         fn = fib6_add_1(root, &rt->rt6i_dst.addr, sizeof(struct in6_addr),
691                         rt->rt6i_dst.plen, offsetof(struct rt6_info, rt6i_dst));
692
693         if (fn == NULL)
694                 goto out;
695
696         pn = fn;
697
698 #ifdef CONFIG_IPV6_SUBTREES
699         if (rt->rt6i_src.plen) {
700                 struct fib6_node *sn;
701
702                 if (fn->subtree == NULL) {
703                         struct fib6_node *sfn;
704
705                         /*
706                          * Create subtree.
707                          *
708                          *              fn[main tree]
709                          *              |
710                          *              sfn[subtree root]
711                          *                 \
712                          *                  sn[new leaf node]
713                          */
714
715                         /* Create subtree root node */
716                         sfn = node_alloc();
717                         if (sfn == NULL)
718                                 goto st_failure;
719
720                         sfn->leaf = info->nl_net->ipv6.ip6_null_entry;
721                         atomic_inc(&info->nl_net->ipv6.ip6_null_entry->rt6i_ref);
722                         sfn->fn_flags = RTN_ROOT;
723                         sfn->fn_sernum = fib6_new_sernum();
724
725                         /* Now add the first leaf node to new subtree */
726
727                         sn = fib6_add_1(sfn, &rt->rt6i_src.addr,
728                                         sizeof(struct in6_addr), rt->rt6i_src.plen,
729                                         offsetof(struct rt6_info, rt6i_src));
730
731                         if (sn == NULL) {
732                                 /* If it is failed, discard just allocated
733                                    root, and then (in st_failure) stale node
734                                    in main tree.
735                                  */
736                                 node_free(sfn);
737                                 goto st_failure;
738                         }
739
740                         /* Now link new subtree to main tree */
741                         sfn->parent = fn;
742                         fn->subtree = sfn;
743                 } else {
744                         sn = fib6_add_1(fn->subtree, &rt->rt6i_src.addr,
745                                         sizeof(struct in6_addr), rt->rt6i_src.plen,
746                                         offsetof(struct rt6_info, rt6i_src));
747
748                         if (sn == NULL)
749                                 goto st_failure;
750                 }
751
752                 if (fn->leaf == NULL) {
753                         fn->leaf = rt;
754                         atomic_inc(&rt->rt6i_ref);
755                 }
756                 fn = sn;
757         }
758 #endif
759
760         err = fib6_add_rt2node(fn, rt, info);
761
762         if (err == 0) {
763                 fib6_start_gc(info->nl_net, rt);
764                 if (!(rt->rt6i_flags&RTF_CACHE))
765                         fib6_prune_clones(info->nl_net, pn, rt);
766         }
767
768 out:
769         if (err) {
770 #ifdef CONFIG_IPV6_SUBTREES
771                 /*
772                  * If fib6_add_1 has cleared the old leaf pointer in the
773                  * super-tree leaf node we have to find a new one for it.
774                  */
775                 if (pn != fn && pn->leaf == rt) {
776                         pn->leaf = NULL;
777                         atomic_dec(&rt->rt6i_ref);
778                 }
779                 if (pn != fn && !pn->leaf && !(pn->fn_flags & RTN_RTINFO)) {
780                         pn->leaf = fib6_find_prefix(info->nl_net, pn);
781 #if RT6_DEBUG >= 2
782                         if (!pn->leaf) {
783                                 BUG_TRAP(pn->leaf != NULL);
784                                 pn->leaf = info->nl_net->ipv6.ip6_null_entry;
785                         }
786 #endif
787                         atomic_inc(&pn->leaf->rt6i_ref);
788                 }
789 #endif
790                 dst_free(&rt->u.dst);
791         }
792         return err;
793
794 #ifdef CONFIG_IPV6_SUBTREES
795         /* Subtree creation failed, probably main tree node
796            is orphan. If it is, shoot it.
797          */
798 st_failure:
799         if (fn && !(fn->fn_flags & (RTN_RTINFO|RTN_ROOT)))
800                 fib6_repair_tree(info->nl_net, fn);
801         dst_free(&rt->u.dst);
802         return err;
803 #endif
804 }
805
806 /*
807  *      Routing tree lookup
808  *
809  */
810
811 struct lookup_args {
812         int             offset;         /* key offset on rt6_info       */
813         struct in6_addr *addr;          /* search key                   */
814 };
815
816 static struct fib6_node * fib6_lookup_1(struct fib6_node *root,
817                                         struct lookup_args *args)
818 {
819         struct fib6_node *fn;
820         __be32 dir;
821
822         if (unlikely(args->offset == 0))
823                 return NULL;
824
825         /*
826          *      Descend on a tree
827          */
828
829         fn = root;
830
831         for (;;) {
832                 struct fib6_node *next;
833
834                 dir = addr_bit_set(args->addr, fn->fn_bit);
835
836                 next = dir ? fn->right : fn->left;
837
838                 if (next) {
839                         fn = next;
840                         continue;
841                 }
842
843                 break;
844         }
845
846         while(fn) {
847                 if (FIB6_SUBTREE(fn) || fn->fn_flags & RTN_RTINFO) {
848                         struct rt6key *key;
849
850                         key = (struct rt6key *) ((u8 *) fn->leaf +
851                                                  args->offset);
852
853                         if (ipv6_prefix_equal(&key->addr, args->addr, key->plen)) {
854 #ifdef CONFIG_IPV6_SUBTREES
855                                 if (fn->subtree)
856                                         fn = fib6_lookup_1(fn->subtree, args + 1);
857 #endif
858                                 if (!fn || fn->fn_flags & RTN_RTINFO)
859                                         return fn;
860                         }
861                 }
862
863                 if (fn->fn_flags & RTN_ROOT)
864                         break;
865
866                 fn = fn->parent;
867         }
868
869         return NULL;
870 }
871
872 struct fib6_node * fib6_lookup(struct fib6_node *root, struct in6_addr *daddr,
873                                struct in6_addr *saddr)
874 {
875         struct fib6_node *fn;
876         struct lookup_args args[] = {
877                 {
878                         .offset = offsetof(struct rt6_info, rt6i_dst),
879                         .addr = daddr,
880                 },
881 #ifdef CONFIG_IPV6_SUBTREES
882                 {
883                         .offset = offsetof(struct rt6_info, rt6i_src),
884                         .addr = saddr,
885                 },
886 #endif
887                 {
888                         .offset = 0,    /* sentinel */
889                 }
890         };
891
892         fn = fib6_lookup_1(root, daddr ? args : args + 1);
893
894         if (fn == NULL || fn->fn_flags & RTN_TL_ROOT)
895                 fn = root;
896
897         return fn;
898 }
899
900 /*
901  *      Get node with specified destination prefix (and source prefix,
902  *      if subtrees are used)
903  */
904
905
906 static struct fib6_node * fib6_locate_1(struct fib6_node *root,
907                                         struct in6_addr *addr,
908                                         int plen, int offset)
909 {
910         struct fib6_node *fn;
911
912         for (fn = root; fn ; ) {
913                 struct rt6key *key = (struct rt6key *)((u8 *)fn->leaf + offset);
914
915                 /*
916                  *      Prefix match
917                  */
918                 if (plen < fn->fn_bit ||
919                     !ipv6_prefix_equal(&key->addr, addr, fn->fn_bit))
920                         return NULL;
921
922                 if (plen == fn->fn_bit)
923                         return fn;
924
925                 /*
926                  *      We have more bits to go
927                  */
928                 if (addr_bit_set(addr, fn->fn_bit))
929                         fn = fn->right;
930                 else
931                         fn = fn->left;
932         }
933         return NULL;
934 }
935
936 struct fib6_node * fib6_locate(struct fib6_node *root,
937                                struct in6_addr *daddr, int dst_len,
938                                struct in6_addr *saddr, int src_len)
939 {
940         struct fib6_node *fn;
941
942         fn = fib6_locate_1(root, daddr, dst_len,
943                            offsetof(struct rt6_info, rt6i_dst));
944
945 #ifdef CONFIG_IPV6_SUBTREES
946         if (src_len) {
947                 BUG_TRAP(saddr!=NULL);
948                 if (fn && fn->subtree)
949                         fn = fib6_locate_1(fn->subtree, saddr, src_len,
950                                            offsetof(struct rt6_info, rt6i_src));
951         }
952 #endif
953
954         if (fn && fn->fn_flags&RTN_RTINFO)
955                 return fn;
956
957         return NULL;
958 }
959
960
961 /*
962  *      Deletion
963  *
964  */
965
966 static struct rt6_info *fib6_find_prefix(struct net *net, struct fib6_node *fn)
967 {
968         if (fn->fn_flags&RTN_ROOT)
969                 return net->ipv6.ip6_null_entry;
970
971         while(fn) {
972                 if(fn->left)
973                         return fn->left->leaf;
974
975                 if(fn->right)
976                         return fn->right->leaf;
977
978                 fn = FIB6_SUBTREE(fn);
979         }
980         return NULL;
981 }
982
983 /*
984  *      Called to trim the tree of intermediate nodes when possible. "fn"
985  *      is the node we want to try and remove.
986  */
987
988 static struct fib6_node *fib6_repair_tree(struct net *net,
989                                            struct fib6_node *fn)
990 {
991         int children;
992         int nstate;
993         struct fib6_node *child, *pn;
994         struct fib6_walker_t *w;
995         int iter = 0;
996
997         for (;;) {
998                 RT6_TRACE("fixing tree: plen=%d iter=%d\n", fn->fn_bit, iter);
999                 iter++;
1000
1001                 BUG_TRAP(!(fn->fn_flags&RTN_RTINFO));
1002                 BUG_TRAP(!(fn->fn_flags&RTN_TL_ROOT));
1003                 BUG_TRAP(fn->leaf==NULL);
1004
1005                 children = 0;
1006                 child = NULL;
1007                 if (fn->right) child = fn->right, children |= 1;
1008                 if (fn->left) child = fn->left, children |= 2;
1009
1010                 if (children == 3 || FIB6_SUBTREE(fn)
1011 #ifdef CONFIG_IPV6_SUBTREES
1012                     /* Subtree root (i.e. fn) may have one child */
1013                     || (children && fn->fn_flags&RTN_ROOT)
1014 #endif
1015                     ) {
1016                         fn->leaf = fib6_find_prefix(net, fn);
1017 #if RT6_DEBUG >= 2
1018                         if (fn->leaf==NULL) {
1019                                 BUG_TRAP(fn->leaf);
1020                                 fn->leaf = net->ipv6.ip6_null_entry;
1021                         }
1022 #endif
1023                         atomic_inc(&fn->leaf->rt6i_ref);
1024                         return fn->parent;
1025                 }
1026
1027                 pn = fn->parent;
1028 #ifdef CONFIG_IPV6_SUBTREES
1029                 if (FIB6_SUBTREE(pn) == fn) {
1030                         BUG_TRAP(fn->fn_flags&RTN_ROOT);
1031                         FIB6_SUBTREE(pn) = NULL;
1032                         nstate = FWS_L;
1033                 } else {
1034                         BUG_TRAP(!(fn->fn_flags&RTN_ROOT));
1035 #endif
1036                         if (pn->right == fn) pn->right = child;
1037                         else if (pn->left == fn) pn->left = child;
1038 #if RT6_DEBUG >= 2
1039                         else BUG_TRAP(0);
1040 #endif
1041                         if (child)
1042                                 child->parent = pn;
1043                         nstate = FWS_R;
1044 #ifdef CONFIG_IPV6_SUBTREES
1045                 }
1046 #endif
1047
1048                 read_lock(&fib6_walker_lock);
1049                 FOR_WALKERS(w) {
1050                         if (child == NULL) {
1051                                 if (w->root == fn) {
1052                                         w->root = w->node = NULL;
1053                                         RT6_TRACE("W %p adjusted by delroot 1\n", w);
1054                                 } else if (w->node == fn) {
1055                                         RT6_TRACE("W %p adjusted by delnode 1, s=%d/%d\n", w, w->state, nstate);
1056                                         w->node = pn;
1057                                         w->state = nstate;
1058                                 }
1059                         } else {
1060                                 if (w->root == fn) {
1061                                         w->root = child;
1062                                         RT6_TRACE("W %p adjusted by delroot 2\n", w);
1063                                 }
1064                                 if (w->node == fn) {
1065                                         w->node = child;
1066                                         if (children&2) {
1067                                                 RT6_TRACE("W %p adjusted by delnode 2, s=%d\n", w, w->state);
1068                                                 w->state = w->state>=FWS_R ? FWS_U : FWS_INIT;
1069                                         } else {
1070                                                 RT6_TRACE("W %p adjusted by delnode 2, s=%d\n", w, w->state);
1071                                                 w->state = w->state>=FWS_C ? FWS_U : FWS_INIT;
1072                                         }
1073                                 }
1074                         }
1075                 }
1076                 read_unlock(&fib6_walker_lock);
1077
1078                 node_free(fn);
1079                 if (pn->fn_flags&RTN_RTINFO || FIB6_SUBTREE(pn))
1080                         return pn;
1081
1082                 rt6_release(pn->leaf);
1083                 pn->leaf = NULL;
1084                 fn = pn;
1085         }
1086 }
1087
1088 static void fib6_del_route(struct fib6_node *fn, struct rt6_info **rtp,
1089                            struct nl_info *info)
1090 {
1091         struct fib6_walker_t *w;
1092         struct rt6_info *rt = *rtp;
1093         struct net *net = info->nl_net;
1094
1095         RT6_TRACE("fib6_del_route\n");
1096
1097         /* Unlink it */
1098         *rtp = rt->u.dst.rt6_next;
1099         rt->rt6i_node = NULL;
1100         net->ipv6.rt6_stats->fib_rt_entries--;
1101         net->ipv6.rt6_stats->fib_discarded_routes++;
1102
1103         /* Reset round-robin state, if necessary */
1104         if (fn->rr_ptr == rt)
1105                 fn->rr_ptr = NULL;
1106
1107         /* Adjust walkers */
1108         read_lock(&fib6_walker_lock);
1109         FOR_WALKERS(w) {
1110                 if (w->state == FWS_C && w->leaf == rt) {
1111                         RT6_TRACE("walker %p adjusted by delroute\n", w);
1112                         w->leaf = rt->u.dst.rt6_next;
1113                         if (w->leaf == NULL)
1114                                 w->state = FWS_U;
1115                 }
1116         }
1117         read_unlock(&fib6_walker_lock);
1118
1119         rt->u.dst.rt6_next = NULL;
1120
1121         /* If it was last route, expunge its radix tree node */
1122         if (fn->leaf == NULL) {
1123                 fn->fn_flags &= ~RTN_RTINFO;
1124                 net->ipv6.rt6_stats->fib_route_nodes--;
1125                 fn = fib6_repair_tree(net, fn);
1126         }
1127
1128         if (atomic_read(&rt->rt6i_ref) != 1) {
1129                 /* This route is used as dummy address holder in some split
1130                  * nodes. It is not leaked, but it still holds other resources,
1131                  * which must be released in time. So, scan ascendant nodes
1132                  * and replace dummy references to this route with references
1133                  * to still alive ones.
1134                  */
1135                 while (fn) {
1136                         if (!(fn->fn_flags&RTN_RTINFO) && fn->leaf == rt) {
1137                                 fn->leaf = fib6_find_prefix(net, fn);
1138                                 atomic_inc(&fn->leaf->rt6i_ref);
1139                                 rt6_release(rt);
1140                         }
1141                         fn = fn->parent;
1142                 }
1143                 /* No more references are possible at this point. */
1144                 BUG_ON(atomic_read(&rt->rt6i_ref) != 1);
1145         }
1146
1147         inet6_rt_notify(RTM_DELROUTE, rt, info);
1148         rt6_release(rt);
1149 }
1150
1151 int fib6_del(struct rt6_info *rt, struct nl_info *info)
1152 {
1153         struct net *net = info->nl_net;
1154         struct fib6_node *fn = rt->rt6i_node;
1155         struct rt6_info **rtp;
1156
1157 #if RT6_DEBUG >= 2
1158         if (rt->u.dst.obsolete>0) {
1159                 BUG_TRAP(fn==NULL);
1160                 return -ENOENT;
1161         }
1162 #endif
1163         if (fn == NULL || rt == net->ipv6.ip6_null_entry)
1164                 return -ENOENT;
1165
1166         BUG_TRAP(fn->fn_flags&RTN_RTINFO);
1167
1168         if (!(rt->rt6i_flags&RTF_CACHE)) {
1169                 struct fib6_node *pn = fn;
1170 #ifdef CONFIG_IPV6_SUBTREES
1171                 /* clones of this route might be in another subtree */
1172                 if (rt->rt6i_src.plen) {
1173                         while (!(pn->fn_flags&RTN_ROOT))
1174                                 pn = pn->parent;
1175                         pn = pn->parent;
1176                 }
1177 #endif
1178                 fib6_prune_clones(info->nl_net, pn, rt);
1179         }
1180
1181         /*
1182          *      Walk the leaf entries looking for ourself
1183          */
1184
1185         for (rtp = &fn->leaf; *rtp; rtp = &(*rtp)->u.dst.rt6_next) {
1186                 if (*rtp == rt) {
1187                         fib6_del_route(fn, rtp, info);
1188                         return 0;
1189                 }
1190         }
1191         return -ENOENT;
1192 }
1193
1194 /*
1195  *      Tree traversal function.
1196  *
1197  *      Certainly, it is not interrupt safe.
1198  *      However, it is internally reenterable wrt itself and fib6_add/fib6_del.
1199  *      It means, that we can modify tree during walking
1200  *      and use this function for garbage collection, clone pruning,
1201  *      cleaning tree when a device goes down etc. etc.
1202  *
1203  *      It guarantees that every node will be traversed,
1204  *      and that it will be traversed only once.
1205  *
1206  *      Callback function w->func may return:
1207  *      0 -> continue walking.
1208  *      positive value -> walking is suspended (used by tree dumps,
1209  *      and probably by gc, if it will be split to several slices)
1210  *      negative value -> terminate walking.
1211  *
1212  *      The function itself returns:
1213  *      0   -> walk is complete.
1214  *      >0  -> walk is incomplete (i.e. suspended)
1215  *      <0  -> walk is terminated by an error.
1216  */
1217
1218 static int fib6_walk_continue(struct fib6_walker_t *w)
1219 {
1220         struct fib6_node *fn, *pn;
1221
1222         for (;;) {
1223                 fn = w->node;
1224                 if (fn == NULL)
1225                         return 0;
1226
1227                 if (w->prune && fn != w->root &&
1228                     fn->fn_flags&RTN_RTINFO && w->state < FWS_C) {
1229                         w->state = FWS_C;
1230                         w->leaf = fn->leaf;
1231                 }
1232                 switch (w->state) {
1233 #ifdef CONFIG_IPV6_SUBTREES
1234                 case FWS_S:
1235                         if (FIB6_SUBTREE(fn)) {
1236                                 w->node = FIB6_SUBTREE(fn);
1237                                 continue;
1238                         }
1239                         w->state = FWS_L;
1240 #endif
1241                 case FWS_L:
1242                         if (fn->left) {
1243                                 w->node = fn->left;
1244                                 w->state = FWS_INIT;
1245                                 continue;
1246                         }
1247                         w->state = FWS_R;
1248                 case FWS_R:
1249                         if (fn->right) {
1250                                 w->node = fn->right;
1251                                 w->state = FWS_INIT;
1252                                 continue;
1253                         }
1254                         w->state = FWS_C;
1255                         w->leaf = fn->leaf;
1256                 case FWS_C:
1257                         if (w->leaf && fn->fn_flags&RTN_RTINFO) {
1258                                 int err = w->func(w);
1259                                 if (err)
1260                                         return err;
1261                                 continue;
1262                         }
1263                         w->state = FWS_U;
1264                 case FWS_U:
1265                         if (fn == w->root)
1266                                 return 0;
1267                         pn = fn->parent;
1268                         w->node = pn;
1269 #ifdef CONFIG_IPV6_SUBTREES
1270                         if (FIB6_SUBTREE(pn) == fn) {
1271                                 BUG_TRAP(fn->fn_flags&RTN_ROOT);
1272                                 w->state = FWS_L;
1273                                 continue;
1274                         }
1275 #endif
1276                         if (pn->left == fn) {
1277                                 w->state = FWS_R;
1278                                 continue;
1279                         }
1280                         if (pn->right == fn) {
1281                                 w->state = FWS_C;
1282                                 w->leaf = w->node->leaf;
1283                                 continue;
1284                         }
1285 #if RT6_DEBUG >= 2
1286                         BUG_TRAP(0);
1287 #endif
1288                 }
1289         }
1290 }
1291
1292 static int fib6_walk(struct fib6_walker_t *w)
1293 {
1294         int res;
1295
1296         w->state = FWS_INIT;
1297         w->node = w->root;
1298
1299         fib6_walker_link(w);
1300         res = fib6_walk_continue(w);
1301         if (res <= 0)
1302                 fib6_walker_unlink(w);
1303         return res;
1304 }
1305
1306 static int fib6_clean_node(struct fib6_walker_t *w)
1307 {
1308         int res;
1309         struct rt6_info *rt;
1310         struct fib6_cleaner_t *c = container_of(w, struct fib6_cleaner_t, w);
1311         struct nl_info info = {
1312                 .nl_net = c->net,
1313         };
1314
1315         for (rt = w->leaf; rt; rt = rt->u.dst.rt6_next) {
1316                 res = c->func(rt, c->arg);
1317                 if (res < 0) {
1318                         w->leaf = rt;
1319                         res = fib6_del(rt, &info);
1320                         if (res) {
1321 #if RT6_DEBUG >= 2
1322                                 printk(KERN_DEBUG "fib6_clean_node: del failed: rt=%p@%p err=%d\n", rt, rt->rt6i_node, res);
1323 #endif
1324                                 continue;
1325                         }
1326                         return 0;
1327                 }
1328                 BUG_TRAP(res==0);
1329         }
1330         w->leaf = rt;
1331         return 0;
1332 }
1333
1334 /*
1335  *      Convenient frontend to tree walker.
1336  *
1337  *      func is called on each route.
1338  *              It may return -1 -> delete this route.
1339  *                            0  -> continue walking
1340  *
1341  *      prune==1 -> only immediate children of node (certainly,
1342  *      ignoring pure split nodes) will be scanned.
1343  */
1344
1345 static void fib6_clean_tree(struct net *net, struct fib6_node *root,
1346                             int (*func)(struct rt6_info *, void *arg),
1347                             int prune, void *arg)
1348 {
1349         struct fib6_cleaner_t c;
1350
1351         c.w.root = root;
1352         c.w.func = fib6_clean_node;
1353         c.w.prune = prune;
1354         c.func = func;
1355         c.arg = arg;
1356         c.net = net;
1357
1358         fib6_walk(&c.w);
1359 }
1360
1361 void fib6_clean_all(struct net *net, int (*func)(struct rt6_info *, void *arg),
1362                     int prune, void *arg)
1363 {
1364         struct fib6_table *table;
1365         struct hlist_node *node;
1366         struct hlist_head *head;
1367         unsigned int h;
1368
1369         rcu_read_lock();
1370         for (h = 0; h < FIB_TABLE_HASHSZ; h++) {
1371                 head = &net->ipv6.fib_table_hash[h];
1372                 hlist_for_each_entry_rcu(table, node, head, tb6_hlist) {
1373                         write_lock_bh(&table->tb6_lock);
1374                         fib6_clean_tree(net, &table->tb6_root,
1375                                         func, prune, arg);
1376                         write_unlock_bh(&table->tb6_lock);
1377                 }
1378         }
1379         rcu_read_unlock();
1380 }
1381
1382 static int fib6_prune_clone(struct rt6_info *rt, void *arg)
1383 {
1384         if (rt->rt6i_flags & RTF_CACHE) {
1385                 RT6_TRACE("pruning clone %p\n", rt);
1386                 return -1;
1387         }
1388
1389         return 0;
1390 }
1391
1392 static void fib6_prune_clones(struct net *net, struct fib6_node *fn,
1393                               struct rt6_info *rt)
1394 {
1395         fib6_clean_tree(net, fn, fib6_prune_clone, 1, rt);
1396 }
1397
1398 /*
1399  *      Garbage collection
1400  */
1401
1402 static struct fib6_gc_args
1403 {
1404         int                     timeout;
1405         int                     more;
1406 } gc_args;
1407
1408 static int fib6_age(struct rt6_info *rt, void *arg)
1409 {
1410         unsigned long now = jiffies;
1411
1412         /*
1413          *      check addrconf expiration here.
1414          *      Routes are expired even if they are in use.
1415          *
1416          *      Also age clones. Note, that clones are aged out
1417          *      only if they are not in use now.
1418          */
1419
1420         if (rt->rt6i_flags&RTF_EXPIRES && rt->rt6i_expires) {
1421                 if (time_after(now, rt->rt6i_expires)) {
1422                         RT6_TRACE("expiring %p\n", rt);
1423                         return -1;
1424                 }
1425                 gc_args.more++;
1426         } else if (rt->rt6i_flags & RTF_CACHE) {
1427                 if (atomic_read(&rt->u.dst.__refcnt) == 0 &&
1428                     time_after_eq(now, rt->u.dst.lastuse + gc_args.timeout)) {
1429                         RT6_TRACE("aging clone %p\n", rt);
1430                         return -1;
1431                 } else if ((rt->rt6i_flags & RTF_GATEWAY) &&
1432                            (!(rt->rt6i_nexthop->flags & NTF_ROUTER))) {
1433                         RT6_TRACE("purging route %p via non-router but gateway\n",
1434                                   rt);
1435                         return -1;
1436                 }
1437                 gc_args.more++;
1438         }
1439
1440         return 0;
1441 }
1442
1443 static DEFINE_SPINLOCK(fib6_gc_lock);
1444
1445 void fib6_run_gc(unsigned long expires, struct net *net)
1446 {
1447         if (expires != ~0UL) {
1448                 spin_lock_bh(&fib6_gc_lock);
1449                 gc_args.timeout = expires ? (int)expires :
1450                         net->ipv6.sysctl.ip6_rt_gc_interval;
1451         } else {
1452                 local_bh_disable();
1453                 if (!spin_trylock(&fib6_gc_lock)) {
1454                         mod_timer(net->ipv6.ip6_fib_timer, jiffies + HZ);
1455                         local_bh_enable();
1456                         return;
1457                 }
1458                 gc_args.timeout = net->ipv6.sysctl.ip6_rt_gc_interval;
1459         }
1460         gc_args.more = 0;
1461
1462         icmp6_dst_gc(&gc_args.more);
1463
1464         fib6_clean_all(net, fib6_age, 0, NULL);
1465
1466         if (gc_args.more)
1467                 mod_timer(net->ipv6.ip6_fib_timer, jiffies +
1468                           net->ipv6.sysctl.ip6_rt_gc_interval);
1469         else {
1470                 del_timer(net->ipv6.ip6_fib_timer);
1471                 net->ipv6.ip6_fib_timer->expires = 0;
1472         }
1473         spin_unlock_bh(&fib6_gc_lock);
1474 }
1475
1476 static void fib6_gc_timer_cb(unsigned long arg)
1477 {
1478         fib6_run_gc(0, (struct net *)arg);
1479 }
1480
1481 static int fib6_net_init(struct net *net)
1482 {
1483         int ret;
1484         struct timer_list *timer;
1485
1486         ret = -ENOMEM;
1487         timer = kzalloc(sizeof(*timer), GFP_KERNEL);
1488         if (!timer)
1489                 goto out;
1490
1491         setup_timer(timer, fib6_gc_timer_cb, (unsigned long)net);
1492         net->ipv6.ip6_fib_timer = timer;
1493
1494         net->ipv6.rt6_stats = kzalloc(sizeof(*net->ipv6.rt6_stats), GFP_KERNEL);
1495         if (!net->ipv6.rt6_stats)
1496                 goto out_timer;
1497
1498         net->ipv6.fib_table_hash =
1499                 kzalloc(sizeof(*net->ipv6.fib_table_hash)*FIB_TABLE_HASHSZ,
1500                         GFP_KERNEL);
1501         if (!net->ipv6.fib_table_hash)
1502                 goto out_rt6_stats;
1503
1504         net->ipv6.fib6_main_tbl = kzalloc(sizeof(*net->ipv6.fib6_main_tbl),
1505                                           GFP_KERNEL);
1506         if (!net->ipv6.fib6_main_tbl)
1507                 goto out_fib_table_hash;
1508
1509         net->ipv6.fib6_main_tbl->tb6_id = RT6_TABLE_MAIN;
1510         net->ipv6.fib6_main_tbl->tb6_root.leaf = net->ipv6.ip6_null_entry;
1511         net->ipv6.fib6_main_tbl->tb6_root.fn_flags =
1512                 RTN_ROOT | RTN_TL_ROOT | RTN_RTINFO;
1513
1514 #ifdef CONFIG_IPV6_MULTIPLE_TABLES
1515         net->ipv6.fib6_local_tbl = kzalloc(sizeof(*net->ipv6.fib6_local_tbl),
1516                                            GFP_KERNEL);
1517         if (!net->ipv6.fib6_local_tbl)
1518                 goto out_fib6_main_tbl;
1519         net->ipv6.fib6_local_tbl->tb6_id = RT6_TABLE_LOCAL;
1520         net->ipv6.fib6_local_tbl->tb6_root.leaf = net->ipv6.ip6_null_entry;
1521         net->ipv6.fib6_local_tbl->tb6_root.fn_flags =
1522                 RTN_ROOT | RTN_TL_ROOT | RTN_RTINFO;
1523 #endif
1524         fib6_tables_init(net);
1525
1526         ret = 0;
1527 out:
1528         return ret;
1529
1530 #ifdef CONFIG_IPV6_MULTIPLE_TABLES
1531 out_fib6_main_tbl:
1532         kfree(net->ipv6.fib6_main_tbl);
1533 #endif
1534 out_fib_table_hash:
1535         kfree(net->ipv6.fib_table_hash);
1536 out_rt6_stats:
1537         kfree(net->ipv6.rt6_stats);
1538 out_timer:
1539         kfree(timer);
1540         goto out;
1541  }
1542
1543 static void fib6_net_exit(struct net *net)
1544 {
1545         rt6_ifdown(net, NULL);
1546         del_timer_sync(net->ipv6.ip6_fib_timer);
1547         kfree(net->ipv6.ip6_fib_timer);
1548 #ifdef CONFIG_IPV6_MULTIPLE_TABLES
1549         kfree(net->ipv6.fib6_local_tbl);
1550 #endif
1551         kfree(net->ipv6.fib6_main_tbl);
1552         kfree(net->ipv6.fib_table_hash);
1553         kfree(net->ipv6.rt6_stats);
1554 }
1555
1556 static struct pernet_operations fib6_net_ops = {
1557         .init = fib6_net_init,
1558         .exit = fib6_net_exit,
1559 };
1560
1561 int __init fib6_init(void)
1562 {
1563         int ret = -ENOMEM;
1564
1565         fib6_node_kmem = kmem_cache_create("fib6_nodes",
1566                                            sizeof(struct fib6_node),
1567                                            0, SLAB_HWCACHE_ALIGN,
1568                                            NULL);
1569         if (!fib6_node_kmem)
1570                 goto out;
1571
1572         ret = register_pernet_subsys(&fib6_net_ops);
1573         if (ret)
1574                 goto out_kmem_cache_create;
1575
1576         ret = __rtnl_register(PF_INET6, RTM_GETROUTE, NULL, inet6_dump_fib);
1577         if (ret)
1578                 goto out_unregister_subsys;
1579 out:
1580         return ret;
1581
1582 out_unregister_subsys:
1583         unregister_pernet_subsys(&fib6_net_ops);
1584 out_kmem_cache_create:
1585         kmem_cache_destroy(fib6_node_kmem);
1586         goto out;
1587 }
1588
1589 void fib6_gc_cleanup(void)
1590 {
1591         unregister_pernet_subsys(&fib6_net_ops);
1592         kmem_cache_destroy(fib6_node_kmem);
1593 }