Merge branch 'misc-2.6.31' into release
[linux-2.6/linux-acpi-2.6/ibm-acpi-2.6.git] / net / ipv4 / fib_hash.c
blobecd39454235c0b12f5d99ed86a554220408f403d
1 /*
2 * INET An implementation of the TCP/IP protocol suite for the LINUX
3 * operating system. INET is implemented using the BSD Socket
4 * interface as the means of communication with the user level.
6 * IPv4 FIB: lookup engine and maintenance routines.
8 * Authors: Alexey Kuznetsov, <kuznet@ms2.inr.ac.ru>
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.
16 #include <asm/uaccess.h>
17 #include <asm/system.h>
18 #include <linux/bitops.h>
19 #include <linux/types.h>
20 #include <linux/kernel.h>
21 #include <linux/mm.h>
22 #include <linux/string.h>
23 #include <linux/socket.h>
24 #include <linux/sockios.h>
25 #include <linux/errno.h>
26 #include <linux/in.h>
27 #include <linux/inet.h>
28 #include <linux/inetdevice.h>
29 #include <linux/netdevice.h>
30 #include <linux/if_arp.h>
31 #include <linux/proc_fs.h>
32 #include <linux/skbuff.h>
33 #include <linux/netlink.h>
34 #include <linux/init.h>
36 #include <net/net_namespace.h>
37 #include <net/ip.h>
38 #include <net/protocol.h>
39 #include <net/route.h>
40 #include <net/tcp.h>
41 #include <net/sock.h>
42 #include <net/ip_fib.h>
44 #include "fib_lookup.h"
46 static struct kmem_cache *fn_hash_kmem __read_mostly;
47 static struct kmem_cache *fn_alias_kmem __read_mostly;
49 struct fib_node {
50 struct hlist_node fn_hash;
51 struct list_head fn_alias;
52 __be32 fn_key;
53 struct fib_alias fn_embedded_alias;
56 struct fn_zone {
57 struct fn_zone *fz_next; /* Next not empty zone */
58 struct hlist_head *fz_hash; /* Hash table pointer */
59 int fz_nent; /* Number of entries */
61 int fz_divisor; /* Hash divisor */
62 u32 fz_hashmask; /* (fz_divisor - 1) */
63 #define FZ_HASHMASK(fz) ((fz)->fz_hashmask)
65 int fz_order; /* Zone order */
66 __be32 fz_mask;
67 #define FZ_MASK(fz) ((fz)->fz_mask)
70 /* NOTE. On fast computers evaluation of fz_hashmask and fz_mask
71 * can be cheaper than memory lookup, so that FZ_* macros are used.
74 struct fn_hash {
75 struct fn_zone *fn_zones[33];
76 struct fn_zone *fn_zone_list;
79 static inline u32 fn_hash(__be32 key, struct fn_zone *fz)
81 u32 h = ntohl(key)>>(32 - fz->fz_order);
82 h ^= (h>>20);
83 h ^= (h>>10);
84 h ^= (h>>5);
85 h &= FZ_HASHMASK(fz);
86 return h;
89 static inline __be32 fz_key(__be32 dst, struct fn_zone *fz)
91 return dst & FZ_MASK(fz);
94 static DEFINE_RWLOCK(fib_hash_lock);
95 static unsigned int fib_hash_genid;
97 #define FZ_MAX_DIVISOR ((PAGE_SIZE<<MAX_ORDER) / sizeof(struct hlist_head))
99 static struct hlist_head *fz_hash_alloc(int divisor)
101 unsigned long size = divisor * sizeof(struct hlist_head);
103 if (size <= PAGE_SIZE) {
104 return kzalloc(size, GFP_KERNEL);
105 } else {
106 return (struct hlist_head *)
107 __get_free_pages(GFP_KERNEL | __GFP_ZERO, get_order(size));
111 /* The fib hash lock must be held when this is called. */
112 static inline void fn_rebuild_zone(struct fn_zone *fz,
113 struct hlist_head *old_ht,
114 int old_divisor)
116 int i;
118 for (i = 0; i < old_divisor; i++) {
119 struct hlist_node *node, *n;
120 struct fib_node *f;
122 hlist_for_each_entry_safe(f, node, n, &old_ht[i], fn_hash) {
123 struct hlist_head *new_head;
125 hlist_del(&f->fn_hash);
127 new_head = &fz->fz_hash[fn_hash(f->fn_key, fz)];
128 hlist_add_head(&f->fn_hash, new_head);
133 static void fz_hash_free(struct hlist_head *hash, int divisor)
135 unsigned long size = divisor * sizeof(struct hlist_head);
137 if (size <= PAGE_SIZE)
138 kfree(hash);
139 else
140 free_pages((unsigned long)hash, get_order(size));
143 static void fn_rehash_zone(struct fn_zone *fz)
145 struct hlist_head *ht, *old_ht;
146 int old_divisor, new_divisor;
147 u32 new_hashmask;
149 old_divisor = fz->fz_divisor;
151 switch (old_divisor) {
152 case 16:
153 new_divisor = 256;
154 break;
155 case 256:
156 new_divisor = 1024;
157 break;
158 default:
159 if ((old_divisor << 1) > FZ_MAX_DIVISOR) {
160 printk(KERN_CRIT "route.c: bad divisor %d!\n", old_divisor);
161 return;
163 new_divisor = (old_divisor << 1);
164 break;
167 new_hashmask = (new_divisor - 1);
169 #if RT_CACHE_DEBUG >= 2
170 printk(KERN_DEBUG "fn_rehash_zone: hash for zone %d grows from %d\n",
171 fz->fz_order, old_divisor);
172 #endif
174 ht = fz_hash_alloc(new_divisor);
176 if (ht) {
177 write_lock_bh(&fib_hash_lock);
178 old_ht = fz->fz_hash;
179 fz->fz_hash = ht;
180 fz->fz_hashmask = new_hashmask;
181 fz->fz_divisor = new_divisor;
182 fn_rebuild_zone(fz, old_ht, old_divisor);
183 fib_hash_genid++;
184 write_unlock_bh(&fib_hash_lock);
186 fz_hash_free(old_ht, old_divisor);
190 static inline void fn_free_node(struct fib_node * f)
192 kmem_cache_free(fn_hash_kmem, f);
195 static inline void fn_free_alias(struct fib_alias *fa, struct fib_node *f)
197 fib_release_info(fa->fa_info);
198 if (fa == &f->fn_embedded_alias)
199 fa->fa_info = NULL;
200 else
201 kmem_cache_free(fn_alias_kmem, fa);
204 static struct fn_zone *
205 fn_new_zone(struct fn_hash *table, int z)
207 int i;
208 struct fn_zone *fz = kzalloc(sizeof(struct fn_zone), GFP_KERNEL);
209 if (!fz)
210 return NULL;
212 if (z) {
213 fz->fz_divisor = 16;
214 } else {
215 fz->fz_divisor = 1;
217 fz->fz_hashmask = (fz->fz_divisor - 1);
218 fz->fz_hash = fz_hash_alloc(fz->fz_divisor);
219 if (!fz->fz_hash) {
220 kfree(fz);
221 return NULL;
223 fz->fz_order = z;
224 fz->fz_mask = inet_make_mask(z);
226 /* Find the first not empty zone with more specific mask */
227 for (i=z+1; i<=32; i++)
228 if (table->fn_zones[i])
229 break;
230 write_lock_bh(&fib_hash_lock);
231 if (i>32) {
232 /* No more specific masks, we are the first. */
233 fz->fz_next = table->fn_zone_list;
234 table->fn_zone_list = fz;
235 } else {
236 fz->fz_next = table->fn_zones[i]->fz_next;
237 table->fn_zones[i]->fz_next = fz;
239 table->fn_zones[z] = fz;
240 fib_hash_genid++;
241 write_unlock_bh(&fib_hash_lock);
242 return fz;
245 static int
246 fn_hash_lookup(struct fib_table *tb, const struct flowi *flp, struct fib_result *res)
248 int err;
249 struct fn_zone *fz;
250 struct fn_hash *t = (struct fn_hash *)tb->tb_data;
252 read_lock(&fib_hash_lock);
253 for (fz = t->fn_zone_list; fz; fz = fz->fz_next) {
254 struct hlist_head *head;
255 struct hlist_node *node;
256 struct fib_node *f;
257 __be32 k = fz_key(flp->fl4_dst, fz);
259 head = &fz->fz_hash[fn_hash(k, fz)];
260 hlist_for_each_entry(f, node, head, fn_hash) {
261 if (f->fn_key != k)
262 continue;
264 err = fib_semantic_match(&f->fn_alias,
265 flp, res,
266 fz->fz_order);
267 if (err <= 0)
268 goto out;
271 err = 1;
272 out:
273 read_unlock(&fib_hash_lock);
274 return err;
277 static void
278 fn_hash_select_default(struct fib_table *tb, const struct flowi *flp, struct fib_result *res)
280 int order, last_idx;
281 struct hlist_node *node;
282 struct fib_node *f;
283 struct fib_info *fi = NULL;
284 struct fib_info *last_resort;
285 struct fn_hash *t = (struct fn_hash *)tb->tb_data;
286 struct fn_zone *fz = t->fn_zones[0];
288 if (fz == NULL)
289 return;
291 last_idx = -1;
292 last_resort = NULL;
293 order = -1;
295 read_lock(&fib_hash_lock);
296 hlist_for_each_entry(f, node, &fz->fz_hash[0], fn_hash) {
297 struct fib_alias *fa;
299 list_for_each_entry(fa, &f->fn_alias, fa_list) {
300 struct fib_info *next_fi = fa->fa_info;
302 if (fa->fa_scope != res->scope ||
303 fa->fa_type != RTN_UNICAST)
304 continue;
306 if (next_fi->fib_priority > res->fi->fib_priority)
307 break;
308 if (!next_fi->fib_nh[0].nh_gw ||
309 next_fi->fib_nh[0].nh_scope != RT_SCOPE_LINK)
310 continue;
311 fa->fa_state |= FA_S_ACCESSED;
313 if (fi == NULL) {
314 if (next_fi != res->fi)
315 break;
316 } else if (!fib_detect_death(fi, order, &last_resort,
317 &last_idx, tb->tb_default)) {
318 fib_result_assign(res, fi);
319 tb->tb_default = order;
320 goto out;
322 fi = next_fi;
323 order++;
327 if (order <= 0 || fi == NULL) {
328 tb->tb_default = -1;
329 goto out;
332 if (!fib_detect_death(fi, order, &last_resort, &last_idx,
333 tb->tb_default)) {
334 fib_result_assign(res, fi);
335 tb->tb_default = order;
336 goto out;
339 if (last_idx >= 0)
340 fib_result_assign(res, last_resort);
341 tb->tb_default = last_idx;
342 out:
343 read_unlock(&fib_hash_lock);
346 /* Insert node F to FZ. */
347 static inline void fib_insert_node(struct fn_zone *fz, struct fib_node *f)
349 struct hlist_head *head = &fz->fz_hash[fn_hash(f->fn_key, fz)];
351 hlist_add_head(&f->fn_hash, head);
354 /* Return the node in FZ matching KEY. */
355 static struct fib_node *fib_find_node(struct fn_zone *fz, __be32 key)
357 struct hlist_head *head = &fz->fz_hash[fn_hash(key, fz)];
358 struct hlist_node *node;
359 struct fib_node *f;
361 hlist_for_each_entry(f, node, head, fn_hash) {
362 if (f->fn_key == key)
363 return f;
366 return NULL;
369 static int fn_hash_insert(struct fib_table *tb, struct fib_config *cfg)
371 struct fn_hash *table = (struct fn_hash *) tb->tb_data;
372 struct fib_node *new_f = NULL;
373 struct fib_node *f;
374 struct fib_alias *fa, *new_fa;
375 struct fn_zone *fz;
376 struct fib_info *fi;
377 u8 tos = cfg->fc_tos;
378 __be32 key;
379 int err;
381 if (cfg->fc_dst_len > 32)
382 return -EINVAL;
384 fz = table->fn_zones[cfg->fc_dst_len];
385 if (!fz && !(fz = fn_new_zone(table, cfg->fc_dst_len)))
386 return -ENOBUFS;
388 key = 0;
389 if (cfg->fc_dst) {
390 if (cfg->fc_dst & ~FZ_MASK(fz))
391 return -EINVAL;
392 key = fz_key(cfg->fc_dst, fz);
395 fi = fib_create_info(cfg);
396 if (IS_ERR(fi))
397 return PTR_ERR(fi);
399 if (fz->fz_nent > (fz->fz_divisor<<1) &&
400 fz->fz_divisor < FZ_MAX_DIVISOR &&
401 (cfg->fc_dst_len == 32 ||
402 (1 << cfg->fc_dst_len) > fz->fz_divisor))
403 fn_rehash_zone(fz);
405 f = fib_find_node(fz, key);
407 if (!f)
408 fa = NULL;
409 else
410 fa = fib_find_alias(&f->fn_alias, tos, fi->fib_priority);
412 /* Now fa, if non-NULL, points to the first fib alias
413 * with the same keys [prefix,tos,priority], if such key already
414 * exists or to the node before which we will insert new one.
416 * If fa is NULL, we will need to allocate a new one and
417 * insert to the head of f.
419 * If f is NULL, no fib node matched the destination key
420 * and we need to allocate a new one of those as well.
423 if (fa && fa->fa_tos == tos &&
424 fa->fa_info->fib_priority == fi->fib_priority) {
425 struct fib_alias *fa_first, *fa_match;
427 err = -EEXIST;
428 if (cfg->fc_nlflags & NLM_F_EXCL)
429 goto out;
431 /* We have 2 goals:
432 * 1. Find exact match for type, scope, fib_info to avoid
433 * duplicate routes
434 * 2. Find next 'fa' (or head), NLM_F_APPEND inserts before it
436 fa_match = NULL;
437 fa_first = fa;
438 fa = list_entry(fa->fa_list.prev, struct fib_alias, fa_list);
439 list_for_each_entry_continue(fa, &f->fn_alias, fa_list) {
440 if (fa->fa_tos != tos)
441 break;
442 if (fa->fa_info->fib_priority != fi->fib_priority)
443 break;
444 if (fa->fa_type == cfg->fc_type &&
445 fa->fa_scope == cfg->fc_scope &&
446 fa->fa_info == fi) {
447 fa_match = fa;
448 break;
452 if (cfg->fc_nlflags & NLM_F_REPLACE) {
453 struct fib_info *fi_drop;
454 u8 state;
456 fa = fa_first;
457 if (fa_match) {
458 if (fa == fa_match)
459 err = 0;
460 goto out;
462 write_lock_bh(&fib_hash_lock);
463 fi_drop = fa->fa_info;
464 fa->fa_info = fi;
465 fa->fa_type = cfg->fc_type;
466 fa->fa_scope = cfg->fc_scope;
467 state = fa->fa_state;
468 fa->fa_state &= ~FA_S_ACCESSED;
469 fib_hash_genid++;
470 write_unlock_bh(&fib_hash_lock);
472 fib_release_info(fi_drop);
473 if (state & FA_S_ACCESSED)
474 rt_cache_flush(cfg->fc_nlinfo.nl_net, -1);
475 rtmsg_fib(RTM_NEWROUTE, key, fa, cfg->fc_dst_len, tb->tb_id,
476 &cfg->fc_nlinfo, NLM_F_REPLACE);
477 return 0;
480 /* Error if we find a perfect match which
481 * uses the same scope, type, and nexthop
482 * information.
484 if (fa_match)
485 goto out;
487 if (!(cfg->fc_nlflags & NLM_F_APPEND))
488 fa = fa_first;
491 err = -ENOENT;
492 if (!(cfg->fc_nlflags & NLM_F_CREATE))
493 goto out;
495 err = -ENOBUFS;
497 if (!f) {
498 new_f = kmem_cache_zalloc(fn_hash_kmem, GFP_KERNEL);
499 if (new_f == NULL)
500 goto out;
502 INIT_HLIST_NODE(&new_f->fn_hash);
503 INIT_LIST_HEAD(&new_f->fn_alias);
504 new_f->fn_key = key;
505 f = new_f;
508 new_fa = &f->fn_embedded_alias;
509 if (new_fa->fa_info != NULL) {
510 new_fa = kmem_cache_alloc(fn_alias_kmem, GFP_KERNEL);
511 if (new_fa == NULL)
512 goto out;
514 new_fa->fa_info = fi;
515 new_fa->fa_tos = tos;
516 new_fa->fa_type = cfg->fc_type;
517 new_fa->fa_scope = cfg->fc_scope;
518 new_fa->fa_state = 0;
521 * Insert new entry to the list.
524 write_lock_bh(&fib_hash_lock);
525 if (new_f)
526 fib_insert_node(fz, new_f);
527 list_add_tail(&new_fa->fa_list,
528 (fa ? &fa->fa_list : &f->fn_alias));
529 fib_hash_genid++;
530 write_unlock_bh(&fib_hash_lock);
532 if (new_f)
533 fz->fz_nent++;
534 rt_cache_flush(cfg->fc_nlinfo.nl_net, -1);
536 rtmsg_fib(RTM_NEWROUTE, key, new_fa, cfg->fc_dst_len, tb->tb_id,
537 &cfg->fc_nlinfo, 0);
538 return 0;
540 out:
541 if (new_f)
542 kmem_cache_free(fn_hash_kmem, new_f);
543 fib_release_info(fi);
544 return err;
548 static int fn_hash_delete(struct fib_table *tb, struct fib_config *cfg)
550 struct fn_hash *table = (struct fn_hash *)tb->tb_data;
551 struct fib_node *f;
552 struct fib_alias *fa, *fa_to_delete;
553 struct fn_zone *fz;
554 __be32 key;
556 if (cfg->fc_dst_len > 32)
557 return -EINVAL;
559 if ((fz = table->fn_zones[cfg->fc_dst_len]) == NULL)
560 return -ESRCH;
562 key = 0;
563 if (cfg->fc_dst) {
564 if (cfg->fc_dst & ~FZ_MASK(fz))
565 return -EINVAL;
566 key = fz_key(cfg->fc_dst, fz);
569 f = fib_find_node(fz, key);
571 if (!f)
572 fa = NULL;
573 else
574 fa = fib_find_alias(&f->fn_alias, cfg->fc_tos, 0);
575 if (!fa)
576 return -ESRCH;
578 fa_to_delete = NULL;
579 fa = list_entry(fa->fa_list.prev, struct fib_alias, fa_list);
580 list_for_each_entry_continue(fa, &f->fn_alias, fa_list) {
581 struct fib_info *fi = fa->fa_info;
583 if (fa->fa_tos != cfg->fc_tos)
584 break;
586 if ((!cfg->fc_type ||
587 fa->fa_type == cfg->fc_type) &&
588 (cfg->fc_scope == RT_SCOPE_NOWHERE ||
589 fa->fa_scope == cfg->fc_scope) &&
590 (!cfg->fc_protocol ||
591 fi->fib_protocol == cfg->fc_protocol) &&
592 fib_nh_match(cfg, fi) == 0) {
593 fa_to_delete = fa;
594 break;
598 if (fa_to_delete) {
599 int kill_fn;
601 fa = fa_to_delete;
602 rtmsg_fib(RTM_DELROUTE, key, fa, cfg->fc_dst_len,
603 tb->tb_id, &cfg->fc_nlinfo, 0);
605 kill_fn = 0;
606 write_lock_bh(&fib_hash_lock);
607 list_del(&fa->fa_list);
608 if (list_empty(&f->fn_alias)) {
609 hlist_del(&f->fn_hash);
610 kill_fn = 1;
612 fib_hash_genid++;
613 write_unlock_bh(&fib_hash_lock);
615 if (fa->fa_state & FA_S_ACCESSED)
616 rt_cache_flush(cfg->fc_nlinfo.nl_net, -1);
617 fn_free_alias(fa, f);
618 if (kill_fn) {
619 fn_free_node(f);
620 fz->fz_nent--;
623 return 0;
625 return -ESRCH;
628 static int fn_flush_list(struct fn_zone *fz, int idx)
630 struct hlist_head *head = &fz->fz_hash[idx];
631 struct hlist_node *node, *n;
632 struct fib_node *f;
633 int found = 0;
635 hlist_for_each_entry_safe(f, node, n, head, fn_hash) {
636 struct fib_alias *fa, *fa_node;
637 int kill_f;
639 kill_f = 0;
640 list_for_each_entry_safe(fa, fa_node, &f->fn_alias, fa_list) {
641 struct fib_info *fi = fa->fa_info;
643 if (fi && (fi->fib_flags&RTNH_F_DEAD)) {
644 write_lock_bh(&fib_hash_lock);
645 list_del(&fa->fa_list);
646 if (list_empty(&f->fn_alias)) {
647 hlist_del(&f->fn_hash);
648 kill_f = 1;
650 fib_hash_genid++;
651 write_unlock_bh(&fib_hash_lock);
653 fn_free_alias(fa, f);
654 found++;
657 if (kill_f) {
658 fn_free_node(f);
659 fz->fz_nent--;
662 return found;
665 static int fn_hash_flush(struct fib_table *tb)
667 struct fn_hash *table = (struct fn_hash *) tb->tb_data;
668 struct fn_zone *fz;
669 int found = 0;
671 for (fz = table->fn_zone_list; fz; fz = fz->fz_next) {
672 int i;
674 for (i = fz->fz_divisor - 1; i >= 0; i--)
675 found += fn_flush_list(fz, i);
677 return found;
681 static inline int
682 fn_hash_dump_bucket(struct sk_buff *skb, struct netlink_callback *cb,
683 struct fib_table *tb,
684 struct fn_zone *fz,
685 struct hlist_head *head)
687 struct hlist_node *node;
688 struct fib_node *f;
689 int i, s_i;
691 s_i = cb->args[4];
692 i = 0;
693 hlist_for_each_entry(f, node, head, fn_hash) {
694 struct fib_alias *fa;
696 list_for_each_entry(fa, &f->fn_alias, fa_list) {
697 if (i < s_i)
698 goto next;
700 if (fib_dump_info(skb, NETLINK_CB(cb->skb).pid,
701 cb->nlh->nlmsg_seq,
702 RTM_NEWROUTE,
703 tb->tb_id,
704 fa->fa_type,
705 fa->fa_scope,
706 f->fn_key,
707 fz->fz_order,
708 fa->fa_tos,
709 fa->fa_info,
710 NLM_F_MULTI) < 0) {
711 cb->args[4] = i;
712 return -1;
714 next:
715 i++;
718 cb->args[4] = i;
719 return skb->len;
722 static inline int
723 fn_hash_dump_zone(struct sk_buff *skb, struct netlink_callback *cb,
724 struct fib_table *tb,
725 struct fn_zone *fz)
727 int h, s_h;
729 if (fz->fz_hash == NULL)
730 return skb->len;
731 s_h = cb->args[3];
732 for (h = s_h; h < fz->fz_divisor; h++) {
733 if (hlist_empty(&fz->fz_hash[h]))
734 continue;
735 if (fn_hash_dump_bucket(skb, cb, tb, fz, &fz->fz_hash[h]) < 0) {
736 cb->args[3] = h;
737 return -1;
739 memset(&cb->args[4], 0,
740 sizeof(cb->args) - 4*sizeof(cb->args[0]));
742 cb->args[3] = h;
743 return skb->len;
746 static int fn_hash_dump(struct fib_table *tb, struct sk_buff *skb, struct netlink_callback *cb)
748 int m, s_m;
749 struct fn_zone *fz;
750 struct fn_hash *table = (struct fn_hash *)tb->tb_data;
752 s_m = cb->args[2];
753 read_lock(&fib_hash_lock);
754 for (fz = table->fn_zone_list, m=0; fz; fz = fz->fz_next, m++) {
755 if (m < s_m) continue;
756 if (fn_hash_dump_zone(skb, cb, tb, fz) < 0) {
757 cb->args[2] = m;
758 read_unlock(&fib_hash_lock);
759 return -1;
761 memset(&cb->args[3], 0,
762 sizeof(cb->args) - 3*sizeof(cb->args[0]));
764 read_unlock(&fib_hash_lock);
765 cb->args[2] = m;
766 return skb->len;
769 void __init fib_hash_init(void)
771 fn_hash_kmem = kmem_cache_create("ip_fib_hash", sizeof(struct fib_node),
772 0, SLAB_PANIC, NULL);
774 fn_alias_kmem = kmem_cache_create("ip_fib_alias", sizeof(struct fib_alias),
775 0, SLAB_PANIC, NULL);
779 struct fib_table *fib_hash_table(u32 id)
781 struct fib_table *tb;
783 tb = kmalloc(sizeof(struct fib_table) + sizeof(struct fn_hash),
784 GFP_KERNEL);
785 if (tb == NULL)
786 return NULL;
788 tb->tb_id = id;
789 tb->tb_default = -1;
790 tb->tb_lookup = fn_hash_lookup;
791 tb->tb_insert = fn_hash_insert;
792 tb->tb_delete = fn_hash_delete;
793 tb->tb_flush = fn_hash_flush;
794 tb->tb_select_default = fn_hash_select_default;
795 tb->tb_dump = fn_hash_dump;
796 memset(tb->tb_data, 0, sizeof(struct fn_hash));
797 return tb;
800 /* ------------------------------------------------------------------------ */
801 #ifdef CONFIG_PROC_FS
803 struct fib_iter_state {
804 struct seq_net_private p;
805 struct fn_zone *zone;
806 int bucket;
807 struct hlist_head *hash_head;
808 struct fib_node *fn;
809 struct fib_alias *fa;
810 loff_t pos;
811 unsigned int genid;
812 int valid;
815 static struct fib_alias *fib_get_first(struct seq_file *seq)
817 struct fib_iter_state *iter = seq->private;
818 struct fib_table *main_table;
819 struct fn_hash *table;
821 main_table = fib_get_table(seq_file_net(seq), RT_TABLE_MAIN);
822 table = (struct fn_hash *)main_table->tb_data;
824 iter->bucket = 0;
825 iter->hash_head = NULL;
826 iter->fn = NULL;
827 iter->fa = NULL;
828 iter->pos = 0;
829 iter->genid = fib_hash_genid;
830 iter->valid = 1;
832 for (iter->zone = table->fn_zone_list; iter->zone;
833 iter->zone = iter->zone->fz_next) {
834 int maxslot;
836 if (!iter->zone->fz_nent)
837 continue;
839 iter->hash_head = iter->zone->fz_hash;
840 maxslot = iter->zone->fz_divisor;
842 for (iter->bucket = 0; iter->bucket < maxslot;
843 ++iter->bucket, ++iter->hash_head) {
844 struct hlist_node *node;
845 struct fib_node *fn;
847 hlist_for_each_entry(fn, node, iter->hash_head, fn_hash) {
848 struct fib_alias *fa;
850 list_for_each_entry(fa, &fn->fn_alias, fa_list) {
851 iter->fn = fn;
852 iter->fa = fa;
853 goto out;
858 out:
859 return iter->fa;
862 static struct fib_alias *fib_get_next(struct seq_file *seq)
864 struct fib_iter_state *iter = seq->private;
865 struct fib_node *fn;
866 struct fib_alias *fa;
868 /* Advance FA, if any. */
869 fn = iter->fn;
870 fa = iter->fa;
871 if (fa) {
872 BUG_ON(!fn);
873 list_for_each_entry_continue(fa, &fn->fn_alias, fa_list) {
874 iter->fa = fa;
875 goto out;
879 fa = iter->fa = NULL;
881 /* Advance FN. */
882 if (fn) {
883 struct hlist_node *node = &fn->fn_hash;
884 hlist_for_each_entry_continue(fn, node, fn_hash) {
885 iter->fn = fn;
887 list_for_each_entry(fa, &fn->fn_alias, fa_list) {
888 iter->fa = fa;
889 goto out;
894 fn = iter->fn = NULL;
896 /* Advance hash chain. */
897 if (!iter->zone)
898 goto out;
900 for (;;) {
901 struct hlist_node *node;
902 int maxslot;
904 maxslot = iter->zone->fz_divisor;
906 while (++iter->bucket < maxslot) {
907 iter->hash_head++;
909 hlist_for_each_entry(fn, node, iter->hash_head, fn_hash) {
910 list_for_each_entry(fa, &fn->fn_alias, fa_list) {
911 iter->fn = fn;
912 iter->fa = fa;
913 goto out;
918 iter->zone = iter->zone->fz_next;
920 if (!iter->zone)
921 goto out;
923 iter->bucket = 0;
924 iter->hash_head = iter->zone->fz_hash;
926 hlist_for_each_entry(fn, node, iter->hash_head, fn_hash) {
927 list_for_each_entry(fa, &fn->fn_alias, fa_list) {
928 iter->fn = fn;
929 iter->fa = fa;
930 goto out;
934 out:
935 iter->pos++;
936 return fa;
939 static struct fib_alias *fib_get_idx(struct seq_file *seq, loff_t pos)
941 struct fib_iter_state *iter = seq->private;
942 struct fib_alias *fa;
944 if (iter->valid && pos >= iter->pos && iter->genid == fib_hash_genid) {
945 fa = iter->fa;
946 pos -= iter->pos;
947 } else
948 fa = fib_get_first(seq);
950 if (fa)
951 while (pos && (fa = fib_get_next(seq)))
952 --pos;
953 return pos ? NULL : fa;
956 static void *fib_seq_start(struct seq_file *seq, loff_t *pos)
957 __acquires(fib_hash_lock)
959 void *v = NULL;
961 read_lock(&fib_hash_lock);
962 if (fib_get_table(seq_file_net(seq), RT_TABLE_MAIN))
963 v = *pos ? fib_get_idx(seq, *pos - 1) : SEQ_START_TOKEN;
964 return v;
967 static void *fib_seq_next(struct seq_file *seq, void *v, loff_t *pos)
969 ++*pos;
970 return v == SEQ_START_TOKEN ? fib_get_first(seq) : fib_get_next(seq);
973 static void fib_seq_stop(struct seq_file *seq, void *v)
974 __releases(fib_hash_lock)
976 read_unlock(&fib_hash_lock);
979 static unsigned fib_flag_trans(int type, __be32 mask, struct fib_info *fi)
981 static const unsigned type2flags[RTN_MAX + 1] = {
982 [7] = RTF_REJECT, [8] = RTF_REJECT,
984 unsigned flags = type2flags[type];
986 if (fi && fi->fib_nh->nh_gw)
987 flags |= RTF_GATEWAY;
988 if (mask == htonl(0xFFFFFFFF))
989 flags |= RTF_HOST;
990 flags |= RTF_UP;
991 return flags;
995 * This outputs /proc/net/route.
997 * It always works in backward compatibility mode.
998 * The format of the file is not supposed to be changed.
1000 static int fib_seq_show(struct seq_file *seq, void *v)
1002 struct fib_iter_state *iter;
1003 int len;
1004 __be32 prefix, mask;
1005 unsigned flags;
1006 struct fib_node *f;
1007 struct fib_alias *fa;
1008 struct fib_info *fi;
1010 if (v == SEQ_START_TOKEN) {
1011 seq_printf(seq, "%-127s\n", "Iface\tDestination\tGateway "
1012 "\tFlags\tRefCnt\tUse\tMetric\tMask\t\tMTU"
1013 "\tWindow\tIRTT");
1014 goto out;
1017 iter = seq->private;
1018 f = iter->fn;
1019 fa = iter->fa;
1020 fi = fa->fa_info;
1021 prefix = f->fn_key;
1022 mask = FZ_MASK(iter->zone);
1023 flags = fib_flag_trans(fa->fa_type, mask, fi);
1024 if (fi)
1025 seq_printf(seq,
1026 "%s\t%08X\t%08X\t%04X\t%d\t%u\t%d\t%08X\t%d\t%u\t%u%n",
1027 fi->fib_dev ? fi->fib_dev->name : "*", prefix,
1028 fi->fib_nh->nh_gw, flags, 0, 0, fi->fib_priority,
1029 mask, (fi->fib_advmss ? fi->fib_advmss + 40 : 0),
1030 fi->fib_window,
1031 fi->fib_rtt >> 3, &len);
1032 else
1033 seq_printf(seq,
1034 "*\t%08X\t%08X\t%04X\t%d\t%u\t%d\t%08X\t%d\t%u\t%u%n",
1035 prefix, 0, flags, 0, 0, 0, mask, 0, 0, 0, &len);
1037 seq_printf(seq, "%*s\n", 127 - len, "");
1038 out:
1039 return 0;
1042 static const struct seq_operations fib_seq_ops = {
1043 .start = fib_seq_start,
1044 .next = fib_seq_next,
1045 .stop = fib_seq_stop,
1046 .show = fib_seq_show,
1049 static int fib_seq_open(struct inode *inode, struct file *file)
1051 return seq_open_net(inode, file, &fib_seq_ops,
1052 sizeof(struct fib_iter_state));
1055 static const struct file_operations fib_seq_fops = {
1056 .owner = THIS_MODULE,
1057 .open = fib_seq_open,
1058 .read = seq_read,
1059 .llseek = seq_lseek,
1060 .release = seq_release_net,
1063 int __net_init fib_proc_init(struct net *net)
1065 if (!proc_net_fops_create(net, "route", S_IRUGO, &fib_seq_fops))
1066 return -ENOMEM;
1067 return 0;
1070 void __net_exit fib_proc_exit(struct net *net)
1072 proc_net_remove(net, "route");
1074 #endif /* CONFIG_PROC_FS */