2 * This program is free software; you can redistribute it and/or
3 * modify it under the terms of the GNU General Public License
4 * as published by the Free Software Foundation; either version
5 * 2 of the License, or (at your option) any later version.
7 * Robert Olsson <robert.olsson@its.uu.se> Uppsala Universitet
8 * & Swedish University of Agricultural Sciences.
10 * Jens Laas <jens.laas@data.slu.se> Swedish University of
11 * Agricultural Sciences.
13 * Hans Liss <hans.liss@its.uu.se> Uppsala Universitet
15 * This work is based on the LPC-trie which is originally descibed in:
17 * An experimental study of compression methods for dynamic tries
18 * Stefan Nilsson and Matti Tikkanen. Algorithmica, 33(1):19-33, 2002.
19 * http://www.nada.kth.se/~snilsson/public/papers/dyntrie2/
22 * IP-address lookup using LC-tries. Stefan Nilsson and Gunnar Karlsson
23 * IEEE Journal on Selected Areas in Communications, 17(6):1083-1092, June 1999
25 * Version: $Id: fib_trie.c,v 1.3 2005/06/08 14:20:01 robert Exp $
28 * Code from fib_hash has been reused which includes the following header:
31 * INET An implementation of the TCP/IP protocol suite for the LINUX
32 * operating system. INET is implemented using the BSD Socket
33 * interface as the means of communication with the user level.
35 * IPv4 FIB: lookup engine and maintenance routines.
38 * Authors: Alexey Kuznetsov, <kuznet@ms2.inr.ac.ru>
40 * This program is free software; you can redistribute it and/or
41 * modify it under the terms of the GNU General Public License
42 * as published by the Free Software Foundation; either version
43 * 2 of the License, or (at your option) any later version.
45 * Substantial contributions to this work comes from:
47 * David S. Miller, <davem@davemloft.net>
48 * Stephen Hemminger <shemminger@osdl.org>
49 * Paul E. McKenney <paulmck@us.ibm.com>
50 * Patrick McHardy <kaber@trash.net>
53 #define VERSION "0.408"
55 #include <asm/uaccess.h>
56 #include <asm/system.h>
57 #include <linux/bitops.h>
58 #include <linux/types.h>
59 #include <linux/kernel.h>
61 #include <linux/string.h>
62 #include <linux/socket.h>
63 #include <linux/sockios.h>
64 #include <linux/errno.h>
66 #include <linux/inet.h>
67 #include <linux/inetdevice.h>
68 #include <linux/netdevice.h>
69 #include <linux/if_arp.h>
70 #include <linux/proc_fs.h>
71 #include <linux/rcupdate.h>
72 #include <linux/skbuff.h>
73 #include <linux/netlink.h>
74 #include <linux/init.h>
75 #include <linux/list.h>
76 #include <net/net_namespace.h>
78 #include <net/protocol.h>
79 #include <net/route.h>
82 #include <net/ip_fib.h>
83 #include "fib_lookup.h"
85 #define MAX_STAT_DEPTH 32
87 #define KEYLENGTH (8*sizeof(t_key))
89 typedef unsigned int t_key;
93 #define NODE_TYPE_MASK 0x1UL
94 #define NODE_TYPE(node) ((node)->parent & NODE_TYPE_MASK)
96 #define IS_TNODE(n) (!(n->parent & T_LEAF))
97 #define IS_LEAF(n) (n->parent & T_LEAF)
101 unsigned long parent;
106 unsigned long parent;
107 struct hlist_head list;
112 struct hlist_node hlist;
115 struct list_head falh;
120 unsigned long parent;
121 unsigned char pos; /* 2log(KEYLENGTH) bits needed */
122 unsigned char bits; /* 2log(KEYLENGTH) bits needed */
123 unsigned short full_children; /* KEYLENGTH bits needed */
124 unsigned short empty_children; /* KEYLENGTH bits needed */
126 struct node *child[0];
129 #ifdef CONFIG_IP_FIB_TRIE_STATS
130 struct trie_use_stats {
132 unsigned int backtrack;
133 unsigned int semantic_match_passed;
134 unsigned int semantic_match_miss;
135 unsigned int null_node_hit;
136 unsigned int resize_node_skipped;
141 unsigned int totdepth;
142 unsigned int maxdepth;
145 unsigned int nullpointers;
146 unsigned int nodesizes[MAX_STAT_DEPTH];
151 #ifdef CONFIG_IP_FIB_TRIE_STATS
152 struct trie_use_stats stats;
157 static void put_child(struct trie *t, struct tnode *tn, int i, struct node *n);
158 static void tnode_put_child_reorg(struct tnode *tn, int i, struct node *n, int wasfull);
159 static struct node *resize(struct trie *t, struct tnode *tn);
160 static struct tnode *inflate(struct trie *t, struct tnode *tn);
161 static struct tnode *halve(struct trie *t, struct tnode *tn);
162 static void tnode_free(struct tnode *tn);
164 static struct kmem_cache *fn_alias_kmem __read_mostly;
166 static inline struct tnode *node_parent(struct node *node)
170 ret = (struct tnode *)(node->parent & ~NODE_TYPE_MASK);
171 return rcu_dereference(ret);
174 static inline void node_set_parent(struct node *node, struct tnode *ptr)
176 rcu_assign_pointer(node->parent,
177 (unsigned long)ptr | NODE_TYPE(node));
180 /* rcu_read_lock needs to be hold by caller from readside */
182 static inline struct node *tnode_get_child(struct tnode *tn, int i)
184 BUG_ON(i >= 1 << tn->bits);
186 return rcu_dereference(tn->child[i]);
189 static inline int tnode_child_length(const struct tnode *tn)
191 return 1 << tn->bits;
194 static inline t_key mask_pfx(t_key k, unsigned short l)
196 return (l == 0) ? 0 : k >> (KEYLENGTH-l) << (KEYLENGTH-l);
199 static inline t_key tkey_extract_bits(t_key a, int offset, int bits)
201 if (offset < KEYLENGTH)
202 return ((t_key)(a << offset)) >> (KEYLENGTH - bits);
207 static inline int tkey_equals(t_key a, t_key b)
212 static inline int tkey_sub_equals(t_key a, int offset, int bits, t_key b)
214 if (bits == 0 || offset >= KEYLENGTH)
216 bits = bits > KEYLENGTH ? KEYLENGTH : bits;
217 return ((a ^ b) << offset) >> (KEYLENGTH - bits) == 0;
220 static inline int tkey_mismatch(t_key a, int offset, t_key b)
227 while ((diff << i) >> (KEYLENGTH-1) == 0)
233 To understand this stuff, an understanding of keys and all their bits is
234 necessary. Every node in the trie has a key associated with it, but not
235 all of the bits in that key are significant.
237 Consider a node 'n' and its parent 'tp'.
239 If n is a leaf, every bit in its key is significant. Its presence is
240 necessitated by path compression, since during a tree traversal (when
241 searching for a leaf - unless we are doing an insertion) we will completely
242 ignore all skipped bits we encounter. Thus we need to verify, at the end of
243 a potentially successful search, that we have indeed been walking the
246 Note that we can never "miss" the correct key in the tree if present by
247 following the wrong path. Path compression ensures that segments of the key
248 that are the same for all keys with a given prefix are skipped, but the
249 skipped part *is* identical for each node in the subtrie below the skipped
250 bit! trie_insert() in this implementation takes care of that - note the
251 call to tkey_sub_equals() in trie_insert().
253 if n is an internal node - a 'tnode' here, the various parts of its key
254 have many different meanings.
257 _________________________________________________________________
258 | i | i | i | i | i | i | i | N | N | N | S | S | S | S | S | C |
259 -----------------------------------------------------------------
260 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15
262 _________________________________________________________________
263 | C | C | C | u | u | u | u | u | u | u | u | u | u | u | u | u |
264 -----------------------------------------------------------------
265 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31
272 First, let's just ignore the bits that come before the parent tp, that is
273 the bits from 0 to (tp->pos-1). They are *known* but at this point we do
274 not use them for anything.
276 The bits from (tp->pos) to (tp->pos + tp->bits - 1) - "N", above - are the
277 index into the parent's child array. That is, they will be used to find
278 'n' among tp's children.
280 The bits from (tp->pos + tp->bits) to (n->pos - 1) - "S" - are skipped bits
283 All the bits we have seen so far are significant to the node n. The rest
284 of the bits are really not needed or indeed known in n->key.
286 The bits from (n->pos) to (n->pos + n->bits - 1) - "C" - are the index into
287 n's child array, and will of course be different for each child.
290 The rest of the bits, from (n->pos + n->bits) onward, are completely unknown
295 static inline void check_tnode(const struct tnode *tn)
297 WARN_ON(tn && tn->pos+tn->bits > 32);
300 static const int halve_threshold = 25;
301 static const int inflate_threshold = 50;
302 static const int halve_threshold_root = 8;
303 static const int inflate_threshold_root = 15;
306 static void __alias_free_mem(struct rcu_head *head)
308 struct fib_alias *fa = container_of(head, struct fib_alias, rcu);
309 kmem_cache_free(fn_alias_kmem, fa);
312 static inline void alias_free_mem_rcu(struct fib_alias *fa)
314 call_rcu(&fa->rcu, __alias_free_mem);
317 static void __leaf_free_rcu(struct rcu_head *head)
319 kfree(container_of(head, struct leaf, rcu));
322 static void __leaf_info_free_rcu(struct rcu_head *head)
324 kfree(container_of(head, struct leaf_info, rcu));
327 static inline void free_leaf_info(struct leaf_info *leaf)
329 call_rcu(&leaf->rcu, __leaf_info_free_rcu);
332 static struct tnode *tnode_alloc(unsigned int size)
336 if (size <= PAGE_SIZE)
337 return kcalloc(size, 1, GFP_KERNEL);
339 pages = alloc_pages(GFP_KERNEL|__GFP_ZERO, get_order(size));
343 return page_address(pages);
346 static void __tnode_free_rcu(struct rcu_head *head)
348 struct tnode *tn = container_of(head, struct tnode, rcu);
349 unsigned int size = sizeof(struct tnode) +
350 (1 << tn->bits) * sizeof(struct node *);
352 if (size <= PAGE_SIZE)
355 free_pages((unsigned long)tn, get_order(size));
358 static inline void tnode_free(struct tnode *tn)
361 struct leaf *l = (struct leaf *) tn;
362 call_rcu_bh(&l->rcu, __leaf_free_rcu);
364 call_rcu(&tn->rcu, __tnode_free_rcu);
367 static struct leaf *leaf_new(void)
369 struct leaf *l = kmalloc(sizeof(struct leaf), GFP_KERNEL);
372 INIT_HLIST_HEAD(&l->list);
377 static struct leaf_info *leaf_info_new(int plen)
379 struct leaf_info *li = kmalloc(sizeof(struct leaf_info), GFP_KERNEL);
382 INIT_LIST_HEAD(&li->falh);
387 static struct tnode* tnode_new(t_key key, int pos, int bits)
389 int nchildren = 1<<bits;
390 int sz = sizeof(struct tnode) + nchildren * sizeof(struct node *);
391 struct tnode *tn = tnode_alloc(sz);
395 tn->parent = T_TNODE;
399 tn->full_children = 0;
400 tn->empty_children = 1<<bits;
403 pr_debug("AT %p s=%u %u\n", tn, (unsigned int) sizeof(struct tnode),
404 (unsigned int) (sizeof(struct node) * 1<<bits));
409 * Check whether a tnode 'n' is "full", i.e. it is an internal node
410 * and no bits are skipped. See discussion in dyntree paper p. 6
413 static inline int tnode_full(const struct tnode *tn, const struct node *n)
415 if (n == NULL || IS_LEAF(n))
418 return ((struct tnode *) n)->pos == tn->pos + tn->bits;
421 static inline void put_child(struct trie *t, struct tnode *tn, int i, struct node *n)
423 tnode_put_child_reorg(tn, i, n, -1);
427 * Add a child at position i overwriting the old value.
428 * Update the value of full_children and empty_children.
431 static void tnode_put_child_reorg(struct tnode *tn, int i, struct node *n, int wasfull)
433 struct node *chi = tn->child[i];
436 BUG_ON(i >= 1<<tn->bits);
439 /* update emptyChildren */
440 if (n == NULL && chi != NULL)
441 tn->empty_children++;
442 else if (n != NULL && chi == NULL)
443 tn->empty_children--;
445 /* update fullChildren */
447 wasfull = tnode_full(tn, chi);
449 isfull = tnode_full(tn, n);
450 if (wasfull && !isfull)
452 else if (!wasfull && isfull)
456 node_set_parent(n, tn);
458 rcu_assign_pointer(tn->child[i], n);
461 static struct node *resize(struct trie *t, struct tnode *tn)
465 struct tnode *old_tn;
466 int inflate_threshold_use;
467 int halve_threshold_use;
473 pr_debug("In tnode_resize %p inflate_threshold=%d threshold=%d\n",
474 tn, inflate_threshold, halve_threshold);
477 if (tn->empty_children == tnode_child_length(tn)) {
482 if (tn->empty_children == tnode_child_length(tn) - 1)
483 for (i = 0; i < tnode_child_length(tn); i++) {
490 /* compress one level */
491 node_set_parent(n, NULL);
496 * Double as long as the resulting node has a number of
497 * nonempty nodes that are above the threshold.
501 * From "Implementing a dynamic compressed trie" by Stefan Nilsson of
502 * the Helsinki University of Technology and Matti Tikkanen of Nokia
503 * Telecommunications, page 6:
504 * "A node is doubled if the ratio of non-empty children to all
505 * children in the *doubled* node is at least 'high'."
507 * 'high' in this instance is the variable 'inflate_threshold'. It
508 * is expressed as a percentage, so we multiply it with
509 * tnode_child_length() and instead of multiplying by 2 (since the
510 * child array will be doubled by inflate()) and multiplying
511 * the left-hand side by 100 (to handle the percentage thing) we
512 * multiply the left-hand side by 50.
514 * The left-hand side may look a bit weird: tnode_child_length(tn)
515 * - tn->empty_children is of course the number of non-null children
516 * in the current node. tn->full_children is the number of "full"
517 * children, that is non-null tnodes with a skip value of 0.
518 * All of those will be doubled in the resulting inflated tnode, so
519 * we just count them one extra time here.
521 * A clearer way to write this would be:
523 * to_be_doubled = tn->full_children;
524 * not_to_be_doubled = tnode_child_length(tn) - tn->empty_children -
527 * new_child_length = tnode_child_length(tn) * 2;
529 * new_fill_factor = 100 * (not_to_be_doubled + 2*to_be_doubled) /
531 * if (new_fill_factor >= inflate_threshold)
533 * ...and so on, tho it would mess up the while () loop.
536 * 100 * (not_to_be_doubled + 2*to_be_doubled) / new_child_length >=
540 * 100 * (not_to_be_doubled + 2*to_be_doubled) >=
541 * inflate_threshold * new_child_length
543 * expand not_to_be_doubled and to_be_doubled, and shorten:
544 * 100 * (tnode_child_length(tn) - tn->empty_children +
545 * tn->full_children) >= inflate_threshold * new_child_length
547 * expand new_child_length:
548 * 100 * (tnode_child_length(tn) - tn->empty_children +
549 * tn->full_children) >=
550 * inflate_threshold * tnode_child_length(tn) * 2
553 * 50 * (tn->full_children + tnode_child_length(tn) -
554 * tn->empty_children) >= inflate_threshold *
555 * tnode_child_length(tn)
561 /* Keep root node larger */
564 inflate_threshold_use = inflate_threshold_root;
566 inflate_threshold_use = inflate_threshold;
570 while ((tn->full_children > 0 && max_resize-- &&
571 50 * (tn->full_children + tnode_child_length(tn) - tn->empty_children) >=
572 inflate_threshold_use * tnode_child_length(tn))) {
578 #ifdef CONFIG_IP_FIB_TRIE_STATS
579 t->stats.resize_node_skipped++;
585 if (max_resize < 0) {
587 printk(KERN_WARNING "Fix inflate_threshold_root. Now=%d size=%d bits\n",
588 inflate_threshold_root, tn->bits);
590 printk(KERN_WARNING "Fix inflate_threshold. Now=%d size=%d bits\n",
591 inflate_threshold, tn->bits);
597 * Halve as long as the number of empty children in this
598 * node is above threshold.
602 /* Keep root node larger */
605 halve_threshold_use = halve_threshold_root;
607 halve_threshold_use = halve_threshold;
611 while (tn->bits > 1 && max_resize-- &&
612 100 * (tnode_child_length(tn) - tn->empty_children) <
613 halve_threshold_use * tnode_child_length(tn)) {
619 #ifdef CONFIG_IP_FIB_TRIE_STATS
620 t->stats.resize_node_skipped++;
626 if (max_resize < 0) {
628 printk(KERN_WARNING "Fix halve_threshold_root. Now=%d size=%d bits\n",
629 halve_threshold_root, tn->bits);
631 printk(KERN_WARNING "Fix halve_threshold. Now=%d size=%d bits\n",
632 halve_threshold, tn->bits);
635 /* Only one child remains */
636 if (tn->empty_children == tnode_child_length(tn) - 1)
637 for (i = 0; i < tnode_child_length(tn); i++) {
644 /* compress one level */
646 node_set_parent(n, NULL);
651 return (struct node *) tn;
654 static struct tnode *inflate(struct trie *t, struct tnode *tn)
656 struct tnode *oldtnode = tn;
657 int olen = tnode_child_length(tn);
660 pr_debug("In inflate\n");
662 tn = tnode_new(oldtnode->key, oldtnode->pos, oldtnode->bits + 1);
665 return ERR_PTR(-ENOMEM);
668 * Preallocate and store tnodes before the actual work so we
669 * don't get into an inconsistent state if memory allocation
670 * fails. In case of failure we return the oldnode and inflate
671 * of tnode is ignored.
674 for (i = 0; i < olen; i++) {
675 struct tnode *inode = (struct tnode *) tnode_get_child(oldtnode, i);
679 inode->pos == oldtnode->pos + oldtnode->bits &&
681 struct tnode *left, *right;
682 t_key m = ~0U << (KEYLENGTH - 1) >> inode->pos;
684 left = tnode_new(inode->key&(~m), inode->pos + 1,
689 right = tnode_new(inode->key|m, inode->pos + 1,
697 put_child(t, tn, 2*i, (struct node *) left);
698 put_child(t, tn, 2*i+1, (struct node *) right);
702 for (i = 0; i < olen; i++) {
704 struct node *node = tnode_get_child(oldtnode, i);
705 struct tnode *left, *right;
712 /* A leaf or an internal node with skipped bits */
714 if (IS_LEAF(node) || ((struct tnode *) node)->pos >
715 tn->pos + tn->bits - 1) {
716 if (tkey_extract_bits(node->key, oldtnode->pos + oldtnode->bits,
718 put_child(t, tn, 2*i, node);
720 put_child(t, tn, 2*i+1, node);
724 /* An internal node with two children */
725 inode = (struct tnode *) node;
727 if (inode->bits == 1) {
728 put_child(t, tn, 2*i, inode->child[0]);
729 put_child(t, tn, 2*i+1, inode->child[1]);
735 /* An internal node with more than two children */
737 /* We will replace this node 'inode' with two new
738 * ones, 'left' and 'right', each with half of the
739 * original children. The two new nodes will have
740 * a position one bit further down the key and this
741 * means that the "significant" part of their keys
742 * (see the discussion near the top of this file)
743 * will differ by one bit, which will be "0" in
744 * left's key and "1" in right's key. Since we are
745 * moving the key position by one step, the bit that
746 * we are moving away from - the bit at position
747 * (inode->pos) - is the one that will differ between
748 * left and right. So... we synthesize that bit in the
750 * The mask 'm' below will be a single "one" bit at
751 * the position (inode->pos)
754 /* Use the old key, but set the new significant
758 left = (struct tnode *) tnode_get_child(tn, 2*i);
759 put_child(t, tn, 2*i, NULL);
763 right = (struct tnode *) tnode_get_child(tn, 2*i+1);
764 put_child(t, tn, 2*i+1, NULL);
768 size = tnode_child_length(left);
769 for (j = 0; j < size; j++) {
770 put_child(t, left, j, inode->child[j]);
771 put_child(t, right, j, inode->child[j + size]);
773 put_child(t, tn, 2*i, resize(t, left));
774 put_child(t, tn, 2*i+1, resize(t, right));
778 tnode_free(oldtnode);
782 int size = tnode_child_length(tn);
785 for (j = 0; j < size; j++)
787 tnode_free((struct tnode *)tn->child[j]);
791 return ERR_PTR(-ENOMEM);
795 static struct tnode *halve(struct trie *t, struct tnode *tn)
797 struct tnode *oldtnode = tn;
798 struct node *left, *right;
800 int olen = tnode_child_length(tn);
802 pr_debug("In halve\n");
804 tn = tnode_new(oldtnode->key, oldtnode->pos, oldtnode->bits - 1);
807 return ERR_PTR(-ENOMEM);
810 * Preallocate and store tnodes before the actual work so we
811 * don't get into an inconsistent state if memory allocation
812 * fails. In case of failure we return the oldnode and halve
813 * of tnode is ignored.
816 for (i = 0; i < olen; i += 2) {
817 left = tnode_get_child(oldtnode, i);
818 right = tnode_get_child(oldtnode, i+1);
820 /* Two nonempty children */
824 newn = tnode_new(left->key, tn->pos + tn->bits, 1);
829 put_child(t, tn, i/2, (struct node *)newn);
834 for (i = 0; i < olen; i += 2) {
835 struct tnode *newBinNode;
837 left = tnode_get_child(oldtnode, i);
838 right = tnode_get_child(oldtnode, i+1);
840 /* At least one of the children is empty */
842 if (right == NULL) /* Both are empty */
844 put_child(t, tn, i/2, right);
849 put_child(t, tn, i/2, left);
853 /* Two nonempty children */
854 newBinNode = (struct tnode *) tnode_get_child(tn, i/2);
855 put_child(t, tn, i/2, NULL);
856 put_child(t, newBinNode, 0, left);
857 put_child(t, newBinNode, 1, right);
858 put_child(t, tn, i/2, resize(t, newBinNode));
860 tnode_free(oldtnode);
864 int size = tnode_child_length(tn);
867 for (j = 0; j < size; j++)
869 tnode_free((struct tnode *)tn->child[j]);
873 return ERR_PTR(-ENOMEM);
877 /* readside must use rcu_read_lock currently dump routines
878 via get_fa_head and dump */
880 static struct leaf_info *find_leaf_info(struct leaf *l, int plen)
882 struct hlist_head *head = &l->list;
883 struct hlist_node *node;
884 struct leaf_info *li;
886 hlist_for_each_entry_rcu(li, node, head, hlist)
887 if (li->plen == plen)
893 static inline struct list_head * get_fa_head(struct leaf *l, int plen)
895 struct leaf_info *li = find_leaf_info(l, plen);
903 static void insert_leaf_info(struct hlist_head *head, struct leaf_info *new)
905 struct leaf_info *li = NULL, *last = NULL;
906 struct hlist_node *node;
908 if (hlist_empty(head)) {
909 hlist_add_head_rcu(&new->hlist, head);
911 hlist_for_each_entry(li, node, head, hlist) {
912 if (new->plen > li->plen)
918 hlist_add_after_rcu(&last->hlist, &new->hlist);
920 hlist_add_before_rcu(&new->hlist, &li->hlist);
924 /* rcu_read_lock needs to be hold by caller from readside */
927 fib_find_node(struct trie *t, u32 key)
934 n = rcu_dereference(t->trie);
936 while (n != NULL && NODE_TYPE(n) == T_TNODE) {
937 tn = (struct tnode *) n;
941 if (tkey_sub_equals(tn->key, pos, tn->pos-pos, key)) {
942 pos = tn->pos + tn->bits;
943 n = tnode_get_child(tn, tkey_extract_bits(key, tn->pos, tn->bits));
947 /* Case we have found a leaf. Compare prefixes */
949 if (n != NULL && IS_LEAF(n) && tkey_equals(key, n->key))
950 return (struct leaf *)n;
955 static struct node *trie_rebalance(struct trie *t, struct tnode *tn)
958 t_key cindex, key = tn->key;
961 while (tn != NULL && (tp = node_parent((struct node *)tn)) != NULL) {
962 cindex = tkey_extract_bits(key, tp->pos, tp->bits);
963 wasfull = tnode_full(tp, tnode_get_child(tp, cindex));
964 tn = (struct tnode *) resize (t, (struct tnode *)tn);
965 tnode_put_child_reorg((struct tnode *)tp, cindex,(struct node*)tn, wasfull);
967 tp = node_parent((struct node *) tn);
973 /* Handle last (top) tnode */
975 tn = (struct tnode*) resize(t, (struct tnode *)tn);
977 return (struct node*) tn;
980 /* only used from updater-side */
982 static struct list_head *fib_insert_node(struct trie *t, u32 key, int plen)
985 struct tnode *tp = NULL, *tn = NULL;
989 struct list_head *fa_head = NULL;
990 struct leaf_info *li;
996 /* If we point to NULL, stop. Either the tree is empty and we should
997 * just put a new leaf in if, or we have reached an empty child slot,
998 * and we should just put our new leaf in that.
999 * If we point to a T_TNODE, check if it matches our key. Note that
1000 * a T_TNODE might be skipping any number of bits - its 'pos' need
1001 * not be the parent's 'pos'+'bits'!
1003 * If it does match the current key, get pos/bits from it, extract
1004 * the index from our key, push the T_TNODE and walk the tree.
1006 * If it doesn't, we have to replace it with a new T_TNODE.
1008 * If we point to a T_LEAF, it might or might not have the same key
1009 * as we do. If it does, just change the value, update the T_LEAF's
1010 * value, and return it.
1011 * If it doesn't, we need to replace it with a T_TNODE.
1014 while (n != NULL && NODE_TYPE(n) == T_TNODE) {
1015 tn = (struct tnode *) n;
1019 if (tkey_sub_equals(tn->key, pos, tn->pos-pos, key)) {
1021 pos = tn->pos + tn->bits;
1022 n = tnode_get_child(tn, tkey_extract_bits(key, tn->pos, tn->bits));
1024 BUG_ON(n && node_parent(n) != tn);
1030 * n ----> NULL, LEAF or TNODE
1032 * tp is n's (parent) ----> NULL or TNODE
1035 BUG_ON(tp && IS_LEAF(tp));
1037 /* Case 1: n is a leaf. Compare prefixes */
1039 if (n != NULL && IS_LEAF(n) && tkey_equals(key, n->key)) {
1040 l = (struct leaf *) n;
1041 li = leaf_info_new(plen);
1046 fa_head = &li->falh;
1047 insert_leaf_info(&l->list, li);
1057 li = leaf_info_new(plen);
1060 tnode_free((struct tnode *) l);
1064 fa_head = &li->falh;
1065 insert_leaf_info(&l->list, li);
1067 if (t->trie && n == NULL) {
1068 /* Case 2: n is NULL, and will just insert a new leaf */
1070 node_set_parent((struct node *)l, tp);
1072 cindex = tkey_extract_bits(key, tp->pos, tp->bits);
1073 put_child(t, (struct tnode *)tp, cindex, (struct node *)l);
1075 /* Case 3: n is a LEAF or a TNODE and the key doesn't match. */
1077 * Add a new tnode here
1078 * first tnode need some special handling
1082 pos = tp->pos+tp->bits;
1087 newpos = tkey_mismatch(key, pos, n->key);
1088 tn = tnode_new(n->key, newpos, 1);
1091 tn = tnode_new(key, newpos, 1); /* First tnode */
1096 tnode_free((struct tnode *) l);
1100 node_set_parent((struct node *)tn, tp);
1102 missbit = tkey_extract_bits(key, newpos, 1);
1103 put_child(t, tn, missbit, (struct node *)l);
1104 put_child(t, tn, 1-missbit, n);
1107 cindex = tkey_extract_bits(key, tp->pos, tp->bits);
1108 put_child(t, (struct tnode *)tp, cindex, (struct node *)tn);
1110 rcu_assign_pointer(t->trie, (struct node *)tn); /* First tnode */
1115 if (tp && tp->pos + tp->bits > 32)
1116 printk(KERN_WARNING "fib_trie tp=%p pos=%d, bits=%d, key=%0x plen=%d\n",
1117 tp, tp->pos, tp->bits, key, plen);
1119 /* Rebalance the trie */
1121 rcu_assign_pointer(t->trie, trie_rebalance(t, tp));
1127 * Caller must hold RTNL.
1129 static int fn_trie_insert(struct fib_table *tb, struct fib_config *cfg)
1131 struct trie *t = (struct trie *) tb->tb_data;
1132 struct fib_alias *fa, *new_fa;
1133 struct list_head *fa_head = NULL;
1134 struct fib_info *fi;
1135 int plen = cfg->fc_dst_len;
1136 u8 tos = cfg->fc_tos;
1144 key = ntohl(cfg->fc_dst);
1146 pr_debug("Insert table=%u %08x/%d\n", tb->tb_id, key, plen);
1148 mask = ntohl(inet_make_mask(plen));
1155 fi = fib_create_info(cfg);
1161 l = fib_find_node(t, key);
1165 fa_head = get_fa_head(l, plen);
1166 fa = fib_find_alias(fa_head, tos, fi->fib_priority);
1169 /* Now fa, if non-NULL, points to the first fib alias
1170 * with the same keys [prefix,tos,priority], if such key already
1171 * exists or to the node before which we will insert new one.
1173 * If fa is NULL, we will need to allocate a new one and
1174 * insert to the head of f.
1176 * If f is NULL, no fib node matched the destination key
1177 * and we need to allocate a new one of those as well.
1180 if (fa && fa->fa_info->fib_priority == fi->fib_priority) {
1181 struct fib_alias *fa_orig;
1184 if (cfg->fc_nlflags & NLM_F_EXCL)
1187 if (cfg->fc_nlflags & NLM_F_REPLACE) {
1188 struct fib_info *fi_drop;
1191 if (fi->fib_treeref > 1)
1195 new_fa = kmem_cache_alloc(fn_alias_kmem, GFP_KERNEL);
1199 fi_drop = fa->fa_info;
1200 new_fa->fa_tos = fa->fa_tos;
1201 new_fa->fa_info = fi;
1202 new_fa->fa_type = cfg->fc_type;
1203 new_fa->fa_scope = cfg->fc_scope;
1204 state = fa->fa_state;
1205 new_fa->fa_state &= ~FA_S_ACCESSED;
1207 list_replace_rcu(&fa->fa_list, &new_fa->fa_list);
1208 alias_free_mem_rcu(fa);
1210 fib_release_info(fi_drop);
1211 if (state & FA_S_ACCESSED)
1213 rtmsg_fib(RTM_NEWROUTE, htonl(key), new_fa, plen,
1214 tb->tb_id, &cfg->fc_nlinfo, NLM_F_REPLACE);
1218 /* Error if we find a perfect match which
1219 * uses the same scope, type, and nexthop
1223 list_for_each_entry(fa, fa_orig->fa_list.prev, fa_list) {
1224 if (fa->fa_tos != tos)
1226 if (fa->fa_info->fib_priority != fi->fib_priority)
1228 if (fa->fa_type == cfg->fc_type &&
1229 fa->fa_scope == cfg->fc_scope &&
1230 fa->fa_info == fi) {
1234 if (!(cfg->fc_nlflags & NLM_F_APPEND))
1238 if (!(cfg->fc_nlflags & NLM_F_CREATE))
1242 new_fa = kmem_cache_alloc(fn_alias_kmem, GFP_KERNEL);
1246 new_fa->fa_info = fi;
1247 new_fa->fa_tos = tos;
1248 new_fa->fa_type = cfg->fc_type;
1249 new_fa->fa_scope = cfg->fc_scope;
1250 new_fa->fa_state = 0;
1252 * Insert new entry to the list.
1256 fa_head = fib_insert_node(t, key, plen);
1257 if (unlikely(!fa_head)) {
1259 goto out_free_new_fa;
1263 list_add_tail_rcu(&new_fa->fa_list,
1264 (fa ? &fa->fa_list : fa_head));
1267 rtmsg_fib(RTM_NEWROUTE, htonl(key), new_fa, plen, tb->tb_id,
1268 &cfg->fc_nlinfo, 0);
1273 kmem_cache_free(fn_alias_kmem, new_fa);
1275 fib_release_info(fi);
1281 /* should be called with rcu_read_lock */
1282 static inline int check_leaf(struct trie *t, struct leaf *l,
1283 t_key key, int *plen, const struct flowi *flp,
1284 struct fib_result *res)
1288 struct leaf_info *li;
1289 struct hlist_head *hhead = &l->list;
1290 struct hlist_node *node;
1292 hlist_for_each_entry_rcu(li, node, hhead, hlist) {
1294 mask = inet_make_mask(i);
1295 if (l->key != (key & ntohl(mask)))
1298 if ((err = fib_semantic_match(&li->falh, flp, res, htonl(l->key), mask, i)) <= 0) {
1300 #ifdef CONFIG_IP_FIB_TRIE_STATS
1301 t->stats.semantic_match_passed++;
1305 #ifdef CONFIG_IP_FIB_TRIE_STATS
1306 t->stats.semantic_match_miss++;
1313 fn_trie_lookup(struct fib_table *tb, const struct flowi *flp, struct fib_result *res)
1315 struct trie *t = (struct trie *) tb->tb_data;
1320 t_key key = ntohl(flp->fl4_dst);
1323 int current_prefix_length = KEYLENGTH;
1325 t_key node_prefix, key_prefix, pref_mismatch;
1330 n = rcu_dereference(t->trie);
1334 #ifdef CONFIG_IP_FIB_TRIE_STATS
1340 if ((ret = check_leaf(t, (struct leaf *)n, key, &plen, flp, res)) <= 0)
1344 pn = (struct tnode *) n;
1352 cindex = tkey_extract_bits(mask_pfx(key, current_prefix_length),
1355 n = tnode_get_child(pn, cindex);
1358 #ifdef CONFIG_IP_FIB_TRIE_STATS
1359 t->stats.null_node_hit++;
1365 if ((ret = check_leaf(t, (struct leaf *)n, key, &plen, flp, res)) <= 0)
1373 cn = (struct tnode *)n;
1376 * It's a tnode, and we can do some extra checks here if we
1377 * like, to avoid descending into a dead-end branch.
1378 * This tnode is in the parent's child array at index
1379 * key[p_pos..p_pos+p_bits] but potentially with some bits
1380 * chopped off, so in reality the index may be just a
1381 * subprefix, padded with zero at the end.
1382 * We can also take a look at any skipped bits in this
1383 * tnode - everything up to p_pos is supposed to be ok,
1384 * and the non-chopped bits of the index (se previous
1385 * paragraph) are also guaranteed ok, but the rest is
1386 * considered unknown.
1388 * The skipped bits are key[pos+bits..cn->pos].
1391 /* If current_prefix_length < pos+bits, we are already doing
1392 * actual prefix matching, which means everything from
1393 * pos+(bits-chopped_off) onward must be zero along some
1394 * branch of this subtree - otherwise there is *no* valid
1395 * prefix present. Here we can only check the skipped
1396 * bits. Remember, since we have already indexed into the
1397 * parent's child array, we know that the bits we chopped of
1401 /* NOTA BENE: CHECKING ONLY SKIPPED BITS FOR THE NEW NODE HERE */
1403 if (current_prefix_length < pos+bits) {
1404 if (tkey_extract_bits(cn->key, current_prefix_length,
1405 cn->pos - current_prefix_length) != 0 ||
1411 * If chopped_off=0, the index is fully validated and we
1412 * only need to look at the skipped bits for this, the new,
1413 * tnode. What we actually want to do is to find out if
1414 * these skipped bits match our key perfectly, or if we will
1415 * have to count on finding a matching prefix further down,
1416 * because if we do, we would like to have some way of
1417 * verifying the existence of such a prefix at this point.
1420 /* The only thing we can do at this point is to verify that
1421 * any such matching prefix can indeed be a prefix to our
1422 * key, and if the bits in the node we are inspecting that
1423 * do not match our key are not ZERO, this cannot be true.
1424 * Thus, find out where there is a mismatch (before cn->pos)
1425 * and verify that all the mismatching bits are zero in the
1429 /* Note: We aren't very concerned about the piece of the key
1430 * that precede pn->pos+pn->bits, since these have already been
1431 * checked. The bits after cn->pos aren't checked since these are
1432 * by definition "unknown" at this point. Thus, what we want to
1433 * see is if we are about to enter the "prefix matching" state,
1434 * and in that case verify that the skipped bits that will prevail
1435 * throughout this subtree are zero, as they have to be if we are
1436 * to find a matching prefix.
1439 node_prefix = mask_pfx(cn->key, cn->pos);
1440 key_prefix = mask_pfx(key, cn->pos);
1441 pref_mismatch = key_prefix^node_prefix;
1444 /* In short: If skipped bits in this node do not match the search
1445 * key, enter the "prefix matching" state.directly.
1447 if (pref_mismatch) {
1448 while (!(pref_mismatch & (1<<(KEYLENGTH-1)))) {
1450 pref_mismatch = pref_mismatch <<1;
1452 key_prefix = tkey_extract_bits(cn->key, mp, cn->pos-mp);
1454 if (key_prefix != 0)
1457 if (current_prefix_length >= cn->pos)
1458 current_prefix_length = mp;
1461 pn = (struct tnode *)n; /* Descend */
1468 /* As zero don't change the child key (cindex) */
1469 while ((chopped_off <= pn->bits) && !(cindex & (1<<(chopped_off-1))))
1472 /* Decrease current_... with bits chopped off */
1473 if (current_prefix_length > pn->pos + pn->bits - chopped_off)
1474 current_prefix_length = pn->pos + pn->bits - chopped_off;
1477 * Either we do the actual chop off according or if we have
1478 * chopped off all bits in this tnode walk up to our parent.
1481 if (chopped_off <= pn->bits) {
1482 cindex &= ~(1 << (chopped_off-1));
1484 struct tnode *parent = node_parent((struct node *) pn);
1488 /* Get Child's index */
1489 cindex = tkey_extract_bits(pn->key, parent->pos, parent->bits);
1493 #ifdef CONFIG_IP_FIB_TRIE_STATS
1494 t->stats.backtrack++;
1506 /* only called from updater side */
1507 static int trie_leaf_remove(struct trie *t, t_key key)
1510 struct tnode *tp = NULL;
1511 struct node *n = t->trie;
1514 pr_debug("entering trie_leaf_remove(%p)\n", n);
1516 /* Note that in the case skipped bits, those bits are *not* checked!
1517 * When we finish this, we will have NULL or a T_LEAF, and the
1518 * T_LEAF may or may not match our key.
1521 while (n != NULL && IS_TNODE(n)) {
1522 struct tnode *tn = (struct tnode *) n;
1524 n = tnode_get_child(tn ,tkey_extract_bits(key, tn->pos, tn->bits));
1526 BUG_ON(n && node_parent(n) != tn);
1528 l = (struct leaf *) n;
1530 if (!n || !tkey_equals(l->key, key))
1535 * Remove the leaf and rebalance the tree
1540 tp = node_parent(n);
1541 tnode_free((struct tnode *) n);
1544 cindex = tkey_extract_bits(key, tp->pos, tp->bits);
1545 put_child(t, (struct tnode *)tp, cindex, NULL);
1546 rcu_assign_pointer(t->trie, trie_rebalance(t, tp));
1548 rcu_assign_pointer(t->trie, NULL);
1554 * Caller must hold RTNL.
1556 static int fn_trie_delete(struct fib_table *tb, struct fib_config *cfg)
1558 struct trie *t = (struct trie *) tb->tb_data;
1560 int plen = cfg->fc_dst_len;
1561 u8 tos = cfg->fc_tos;
1562 struct fib_alias *fa, *fa_to_delete;
1563 struct list_head *fa_head;
1565 struct leaf_info *li;
1570 key = ntohl(cfg->fc_dst);
1571 mask = ntohl(inet_make_mask(plen));
1577 l = fib_find_node(t, key);
1582 fa_head = get_fa_head(l, plen);
1583 fa = fib_find_alias(fa_head, tos, 0);
1588 pr_debug("Deleting %08x/%d tos=%d t=%p\n", key, plen, tos, t);
1590 fa_to_delete = NULL;
1591 fa_head = fa->fa_list.prev;
1593 list_for_each_entry(fa, fa_head, fa_list) {
1594 struct fib_info *fi = fa->fa_info;
1596 if (fa->fa_tos != tos)
1599 if ((!cfg->fc_type || fa->fa_type == cfg->fc_type) &&
1600 (cfg->fc_scope == RT_SCOPE_NOWHERE ||
1601 fa->fa_scope == cfg->fc_scope) &&
1602 (!cfg->fc_protocol ||
1603 fi->fib_protocol == cfg->fc_protocol) &&
1604 fib_nh_match(cfg, fi) == 0) {
1614 rtmsg_fib(RTM_DELROUTE, htonl(key), fa, plen, tb->tb_id,
1615 &cfg->fc_nlinfo, 0);
1617 l = fib_find_node(t, key);
1618 li = find_leaf_info(l, plen);
1620 list_del_rcu(&fa->fa_list);
1622 if (list_empty(fa_head)) {
1623 hlist_del_rcu(&li->hlist);
1627 if (hlist_empty(&l->list))
1628 trie_leaf_remove(t, key);
1630 if (fa->fa_state & FA_S_ACCESSED)
1633 fib_release_info(fa->fa_info);
1634 alias_free_mem_rcu(fa);
1638 static int trie_flush_list(struct trie *t, struct list_head *head)
1640 struct fib_alias *fa, *fa_node;
1643 list_for_each_entry_safe(fa, fa_node, head, fa_list) {
1644 struct fib_info *fi = fa->fa_info;
1646 if (fi && (fi->fib_flags & RTNH_F_DEAD)) {
1647 list_del_rcu(&fa->fa_list);
1648 fib_release_info(fa->fa_info);
1649 alias_free_mem_rcu(fa);
1656 static int trie_flush_leaf(struct trie *t, struct leaf *l)
1659 struct hlist_head *lih = &l->list;
1660 struct hlist_node *node, *tmp;
1661 struct leaf_info *li = NULL;
1663 hlist_for_each_entry_safe(li, node, tmp, lih, hlist) {
1664 found += trie_flush_list(t, &li->falh);
1666 if (list_empty(&li->falh)) {
1667 hlist_del_rcu(&li->hlist);
1674 /* rcu_read_lock needs to be hold by caller from readside */
1676 static struct leaf *nextleaf(struct trie *t, struct leaf *thisleaf)
1678 struct node *c = (struct node *) thisleaf;
1681 struct node *trie = rcu_dereference(t->trie);
1687 if (IS_LEAF(trie)) /* trie w. just a leaf */
1688 return (struct leaf *) trie;
1690 p = (struct tnode*) trie; /* Start */
1697 /* Find the next child of the parent */
1699 pos = 1 + tkey_extract_bits(c->key, p->pos, p->bits);
1703 last = 1 << p->bits;
1704 for (idx = pos; idx < last ; idx++) {
1705 c = rcu_dereference(p->child[idx]);
1710 /* Decend if tnode */
1711 while (IS_TNODE(c)) {
1712 p = (struct tnode *) c;
1715 /* Rightmost non-NULL branch */
1716 if (p && IS_TNODE(p))
1717 while (!(c = rcu_dereference(p->child[idx]))
1718 && idx < (1<<p->bits)) idx++;
1720 /* Done with this tnode? */
1721 if (idx >= (1 << p->bits) || !c)
1724 return (struct leaf *) c;
1727 /* No more children go up one step */
1728 c = (struct node *) p;
1731 return NULL; /* Ready. Root of trie */
1735 * Caller must hold RTNL.
1737 static int fn_trie_flush(struct fib_table *tb)
1739 struct trie *t = (struct trie *) tb->tb_data;
1740 struct leaf *ll = NULL, *l = NULL;
1743 for (h = 0; (l = nextleaf(t, l)) != NULL; h++) {
1744 found += trie_flush_leaf(t, l);
1746 if (ll && hlist_empty(&ll->list))
1747 trie_leaf_remove(t, ll->key);
1751 if (ll && hlist_empty(&ll->list))
1752 trie_leaf_remove(t, ll->key);
1754 pr_debug("trie_flush found=%d\n", found);
1759 fn_trie_select_default(struct fib_table *tb, const struct flowi *flp, struct fib_result *res)
1761 struct trie *t = (struct trie *) tb->tb_data;
1762 int order, last_idx;
1763 struct fib_info *fi = NULL;
1764 struct fib_info *last_resort;
1765 struct fib_alias *fa = NULL;
1766 struct list_head *fa_head;
1775 l = fib_find_node(t, 0);
1779 fa_head = get_fa_head(l, 0);
1783 if (list_empty(fa_head))
1786 list_for_each_entry_rcu(fa, fa_head, fa_list) {
1787 struct fib_info *next_fi = fa->fa_info;
1789 if (fa->fa_scope != res->scope ||
1790 fa->fa_type != RTN_UNICAST)
1793 if (next_fi->fib_priority > res->fi->fib_priority)
1795 if (!next_fi->fib_nh[0].nh_gw ||
1796 next_fi->fib_nh[0].nh_scope != RT_SCOPE_LINK)
1798 fa->fa_state |= FA_S_ACCESSED;
1801 if (next_fi != res->fi)
1803 } else if (!fib_detect_death(fi, order, &last_resort,
1804 &last_idx, tb->tb_default)) {
1805 fib_result_assign(res, fi);
1806 tb->tb_default = order;
1812 if (order <= 0 || fi == NULL) {
1813 tb->tb_default = -1;
1817 if (!fib_detect_death(fi, order, &last_resort, &last_idx,
1819 fib_result_assign(res, fi);
1820 tb->tb_default = order;
1824 fib_result_assign(res, last_resort);
1825 tb->tb_default = last_idx;
1830 static int fn_trie_dump_fa(t_key key, int plen, struct list_head *fah, struct fib_table *tb,
1831 struct sk_buff *skb, struct netlink_callback *cb)
1834 struct fib_alias *fa;
1836 __be32 xkey = htonl(key);
1841 /* rcu_read_lock is hold by caller */
1843 list_for_each_entry_rcu(fa, fah, fa_list) {
1848 BUG_ON(!fa->fa_info);
1850 if (fib_dump_info(skb, NETLINK_CB(cb->skb).pid,
1859 fa->fa_info, 0) < 0) {
1869 static int fn_trie_dump_plen(struct trie *t, int plen, struct fib_table *tb, struct sk_buff *skb,
1870 struct netlink_callback *cb)
1873 struct list_head *fa_head;
1874 struct leaf *l = NULL;
1878 for (h = 0; (l = nextleaf(t, l)) != NULL; h++) {
1882 memset(&cb->args[4], 0,
1883 sizeof(cb->args) - 4*sizeof(cb->args[0]));
1885 fa_head = get_fa_head(l, plen);
1890 if (list_empty(fa_head))
1893 if (fn_trie_dump_fa(l->key, plen, fa_head, tb, skb, cb)<0) {
1902 static int fn_trie_dump(struct fib_table *tb, struct sk_buff *skb, struct netlink_callback *cb)
1905 struct trie *t = (struct trie *) tb->tb_data;
1910 for (m = 0; m <= 32; m++) {
1914 memset(&cb->args[3], 0,
1915 sizeof(cb->args) - 3*sizeof(cb->args[0]));
1917 if (fn_trie_dump_plen(t, 32-m, tb, skb, cb)<0) {
1930 /* Fix more generic FIB names for init later */
1932 struct fib_table *fib_hash_init(u32 id)
1934 struct fib_table *tb;
1937 if (fn_alias_kmem == NULL)
1938 fn_alias_kmem = kmem_cache_create("ip_fib_alias",
1939 sizeof(struct fib_alias),
1940 0, SLAB_HWCACHE_ALIGN,
1943 tb = kmalloc(sizeof(struct fib_table) + sizeof(struct trie),
1949 tb->tb_default = -1;
1950 tb->tb_lookup = fn_trie_lookup;
1951 tb->tb_insert = fn_trie_insert;
1952 tb->tb_delete = fn_trie_delete;
1953 tb->tb_flush = fn_trie_flush;
1954 tb->tb_select_default = fn_trie_select_default;
1955 tb->tb_dump = fn_trie_dump;
1957 t = (struct trie *) tb->tb_data;
1958 memset(t, 0, sizeof(*t));
1960 if (id == RT_TABLE_LOCAL)
1961 printk(KERN_INFO "IPv4 FIB: Using LC-trie version %s\n", VERSION);
1966 #ifdef CONFIG_PROC_FS
1967 /* Depth first Trie walk iterator */
1968 struct fib_trie_iter {
1969 struct seq_net_private p;
1970 struct trie *trie_local, *trie_main;
1971 struct tnode *tnode;
1977 static struct node *fib_trie_get_next(struct fib_trie_iter *iter)
1979 struct tnode *tn = iter->tnode;
1980 unsigned cindex = iter->index;
1983 /* A single entry routing table */
1987 pr_debug("get_next iter={node=%p index=%d depth=%d}\n",
1988 iter->tnode, iter->index, iter->depth);
1990 while (cindex < (1<<tn->bits)) {
1991 struct node *n = tnode_get_child(tn, cindex);
1996 iter->index = cindex + 1;
1998 /* push down one level */
1999 iter->tnode = (struct tnode *) n;
2009 /* Current node exhausted, pop back up */
2010 p = node_parent((struct node *)tn);
2012 cindex = tkey_extract_bits(tn->key, p->pos, p->bits)+1;
2022 static struct node *fib_trie_get_first(struct fib_trie_iter *iter,
2030 n = rcu_dereference(t->trie);
2037 iter->tnode = (struct tnode *) n;
2052 static void trie_collect_stats(struct trie *t, struct trie_stat *s)
2055 struct fib_trie_iter iter;
2057 memset(s, 0, sizeof(*s));
2060 for (n = fib_trie_get_first(&iter, t); n;
2061 n = fib_trie_get_next(&iter)) {
2064 s->totdepth += iter.depth;
2065 if (iter.depth > s->maxdepth)
2066 s->maxdepth = iter.depth;
2068 const struct tnode *tn = (const struct tnode *) n;
2072 if (tn->bits < MAX_STAT_DEPTH)
2073 s->nodesizes[tn->bits]++;
2075 for (i = 0; i < (1<<tn->bits); i++)
2084 * This outputs /proc/net/fib_triestats
2086 static void trie_show_stats(struct seq_file *seq, struct trie_stat *stat)
2088 unsigned i, max, pointers, bytes, avdepth;
2091 avdepth = stat->totdepth*100 / stat->leaves;
2095 seq_printf(seq, "\tAver depth: %u.%02d\n", avdepth / 100, avdepth % 100 );
2096 seq_printf(seq, "\tMax depth: %u\n", stat->maxdepth);
2098 seq_printf(seq, "\tLeaves: %u\n", stat->leaves);
2100 bytes = sizeof(struct leaf) * stat->leaves;
2101 seq_printf(seq, "\tInternal nodes: %u\n\t", stat->tnodes);
2102 bytes += sizeof(struct tnode) * stat->tnodes;
2104 max = MAX_STAT_DEPTH;
2105 while (max > 0 && stat->nodesizes[max-1] == 0)
2109 for (i = 1; i <= max; i++)
2110 if (stat->nodesizes[i] != 0) {
2111 seq_printf(seq, " %u: %u", i, stat->nodesizes[i]);
2112 pointers += (1<<i) * stat->nodesizes[i];
2114 seq_putc(seq, '\n');
2115 seq_printf(seq, "\tPointers: %u\n", pointers);
2117 bytes += sizeof(struct node *) * pointers;
2118 seq_printf(seq, "Null ptrs: %u\n", stat->nullpointers);
2119 seq_printf(seq, "Total size: %u kB\n", (bytes + 1023) / 1024);
2122 #ifdef CONFIG_IP_FIB_TRIE_STATS
2123 static void trie_show_usage(struct seq_file *seq,
2124 const struct trie_use_stats *stats)
2126 seq_printf(seq, "\nCounters:\n---------\n");
2127 seq_printf(seq,"gets = %u\n", stats->gets);
2128 seq_printf(seq,"backtracks = %u\n", stats->backtrack);
2129 seq_printf(seq,"semantic match passed = %u\n", stats->semantic_match_passed);
2130 seq_printf(seq,"semantic match miss = %u\n", stats->semantic_match_miss);
2131 seq_printf(seq,"null node hit= %u\n", stats->null_node_hit);
2132 seq_printf(seq,"skipped node resize = %u\n\n", stats->resize_node_skipped);
2134 #endif /* CONFIG_IP_FIB_TRIE_STATS */
2137 static int fib_triestat_seq_show(struct seq_file *seq, void *v)
2139 struct net *net = (struct net *)seq->private;
2140 struct trie *trie_local, *trie_main;
2141 struct trie_stat *stat;
2142 struct fib_table *tb;
2145 tb = fib_get_table(net, RT_TABLE_LOCAL);
2147 trie_local = (struct trie *) tb->tb_data;
2150 tb = fib_get_table(net, RT_TABLE_MAIN);
2152 trie_main = (struct trie *) tb->tb_data;
2155 stat = kmalloc(sizeof(*stat), GFP_KERNEL);
2159 seq_printf(seq, "Basic info: size of leaf: %Zd bytes, size of tnode: %Zd bytes.\n",
2160 sizeof(struct leaf), sizeof(struct tnode));
2163 seq_printf(seq, "Local:\n");
2164 trie_collect_stats(trie_local, stat);
2165 trie_show_stats(seq, stat);
2166 #ifdef CONFIG_IP_FIB_TRIE_STATS
2167 trie_show_usage(seq, &trie_local->stats);
2172 seq_printf(seq, "Main:\n");
2173 trie_collect_stats(trie_main, stat);
2174 trie_show_stats(seq, stat);
2175 #ifdef CONFIG_IP_FIB_TRIE_STATS
2176 trie_show_usage(seq, &trie_main->stats);
2184 static int fib_triestat_seq_open(struct inode *inode, struct file *file)
2189 net = get_proc_net(inode);
2192 err = single_open(file, fib_triestat_seq_show, net);
2200 static int fib_triestat_seq_release(struct inode *ino, struct file *f)
2202 struct seq_file *seq = f->private_data;
2203 put_net(seq->private);
2204 return single_release(ino, f);
2207 static const struct file_operations fib_triestat_fops = {
2208 .owner = THIS_MODULE,
2209 .open = fib_triestat_seq_open,
2211 .llseek = seq_lseek,
2212 .release = fib_triestat_seq_release,
2215 static struct node *fib_trie_get_idx(struct fib_trie_iter *iter,
2221 for (n = fib_trie_get_first(iter, iter->trie_local);
2222 n; ++idx, n = fib_trie_get_next(iter)) {
2227 for (n = fib_trie_get_first(iter, iter->trie_main);
2228 n; ++idx, n = fib_trie_get_next(iter)) {
2235 static void *fib_trie_seq_start(struct seq_file *seq, loff_t *pos)
2238 struct fib_trie_iter *iter = seq->private;
2239 struct fib_table *tb;
2241 if (!iter->trie_local) {
2242 tb = fib_get_table(iter->p.net, RT_TABLE_LOCAL);
2244 iter->trie_local = (struct trie *) tb->tb_data;
2246 if (!iter->trie_main) {
2247 tb = fib_get_table(iter->p.net, RT_TABLE_MAIN);
2249 iter->trie_main = (struct trie *) tb->tb_data;
2253 return SEQ_START_TOKEN;
2254 return fib_trie_get_idx(iter, *pos - 1);
2257 static void *fib_trie_seq_next(struct seq_file *seq, void *v, loff_t *pos)
2259 struct fib_trie_iter *iter = seq->private;
2263 if (v == SEQ_START_TOKEN)
2264 return fib_trie_get_idx(iter, 0);
2266 v = fib_trie_get_next(iter);
2271 /* continue scan in next trie */
2272 if (iter->trie == iter->trie_local)
2273 return fib_trie_get_first(iter, iter->trie_main);
2278 static void fib_trie_seq_stop(struct seq_file *seq, void *v)
2284 static void seq_indent(struct seq_file *seq, int n)
2286 while (n-- > 0) seq_puts(seq, " ");
2289 static inline const char *rtn_scope(enum rt_scope_t s)
2291 static char buf[32];
2294 case RT_SCOPE_UNIVERSE: return "universe";
2295 case RT_SCOPE_SITE: return "site";
2296 case RT_SCOPE_LINK: return "link";
2297 case RT_SCOPE_HOST: return "host";
2298 case RT_SCOPE_NOWHERE: return "nowhere";
2300 snprintf(buf, sizeof(buf), "scope=%d", s);
2305 static const char *rtn_type_names[__RTN_MAX] = {
2306 [RTN_UNSPEC] = "UNSPEC",
2307 [RTN_UNICAST] = "UNICAST",
2308 [RTN_LOCAL] = "LOCAL",
2309 [RTN_BROADCAST] = "BROADCAST",
2310 [RTN_ANYCAST] = "ANYCAST",
2311 [RTN_MULTICAST] = "MULTICAST",
2312 [RTN_BLACKHOLE] = "BLACKHOLE",
2313 [RTN_UNREACHABLE] = "UNREACHABLE",
2314 [RTN_PROHIBIT] = "PROHIBIT",
2315 [RTN_THROW] = "THROW",
2317 [RTN_XRESOLVE] = "XRESOLVE",
2320 static inline const char *rtn_type(unsigned t)
2322 static char buf[32];
2324 if (t < __RTN_MAX && rtn_type_names[t])
2325 return rtn_type_names[t];
2326 snprintf(buf, sizeof(buf), "type %u", t);
2330 /* Pretty print the trie */
2331 static int fib_trie_seq_show(struct seq_file *seq, void *v)
2333 const struct fib_trie_iter *iter = seq->private;
2336 if (v == SEQ_START_TOKEN)
2339 if (!node_parent(n)) {
2340 if (iter->trie == iter->trie_local)
2341 seq_puts(seq, "<local>:\n");
2343 seq_puts(seq, "<main>:\n");
2347 struct tnode *tn = (struct tnode *) n;
2348 __be32 prf = htonl(mask_pfx(tn->key, tn->pos));
2350 seq_indent(seq, iter->depth-1);
2351 seq_printf(seq, " +-- %d.%d.%d.%d/%d %d %d %d\n",
2352 NIPQUAD(prf), tn->pos, tn->bits, tn->full_children,
2353 tn->empty_children);
2356 struct leaf *l = (struct leaf *) n;
2358 __be32 val = htonl(l->key);
2360 seq_indent(seq, iter->depth);
2361 seq_printf(seq, " |-- %d.%d.%d.%d\n", NIPQUAD(val));
2362 for (i = 32; i >= 0; i--) {
2363 struct leaf_info *li = find_leaf_info(l, i);
2365 struct fib_alias *fa;
2366 list_for_each_entry_rcu(fa, &li->falh, fa_list) {
2367 seq_indent(seq, iter->depth+1);
2368 seq_printf(seq, " /%d %s %s", i,
2369 rtn_scope(fa->fa_scope),
2370 rtn_type(fa->fa_type));
2372 seq_printf(seq, "tos =%d\n",
2374 seq_putc(seq, '\n');
2383 static const struct seq_operations fib_trie_seq_ops = {
2384 .start = fib_trie_seq_start,
2385 .next = fib_trie_seq_next,
2386 .stop = fib_trie_seq_stop,
2387 .show = fib_trie_seq_show,
2390 static int fib_trie_seq_open(struct inode *inode, struct file *file)
2392 return seq_open_net(inode, file, &fib_trie_seq_ops,
2393 sizeof(struct fib_trie_iter));
2396 static const struct file_operations fib_trie_fops = {
2397 .owner = THIS_MODULE,
2398 .open = fib_trie_seq_open,
2400 .llseek = seq_lseek,
2401 .release = seq_release_net,
2404 static unsigned fib_flag_trans(int type, __be32 mask, const struct fib_info *fi)
2406 static unsigned type2flags[RTN_MAX + 1] = {
2407 [7] = RTF_REJECT, [8] = RTF_REJECT,
2409 unsigned flags = type2flags[type];
2411 if (fi && fi->fib_nh->nh_gw)
2412 flags |= RTF_GATEWAY;
2413 if (mask == htonl(0xFFFFFFFF))
2420 * This outputs /proc/net/route.
2421 * The format of the file is not supposed to be changed
2422 * and needs to be same as fib_hash output to avoid breaking
2425 static int fib_route_seq_show(struct seq_file *seq, void *v)
2427 const struct fib_trie_iter *iter = seq->private;
2432 if (v == SEQ_START_TOKEN) {
2433 seq_printf(seq, "%-127s\n", "Iface\tDestination\tGateway "
2434 "\tFlags\tRefCnt\tUse\tMetric\tMask\t\tMTU"
2439 if (iter->trie == iter->trie_local)
2444 for (i=32; i>=0; i--) {
2445 struct leaf_info *li = find_leaf_info(l, i);
2446 struct fib_alias *fa;
2447 __be32 mask, prefix;
2452 mask = inet_make_mask(li->plen);
2453 prefix = htonl(l->key);
2455 list_for_each_entry_rcu(fa, &li->falh, fa_list) {
2456 const struct fib_info *fi = fa->fa_info;
2457 unsigned flags = fib_flag_trans(fa->fa_type, mask, fi);
2459 if (fa->fa_type == RTN_BROADCAST
2460 || fa->fa_type == RTN_MULTICAST)
2464 snprintf(bf, sizeof(bf),
2465 "%s\t%08X\t%08X\t%04X\t%d\t%u\t%d\t%08X\t%d\t%u\t%u",
2466 fi->fib_dev ? fi->fib_dev->name : "*",
2468 fi->fib_nh->nh_gw, flags, 0, 0,
2471 (fi->fib_advmss ? fi->fib_advmss + 40 : 0),
2475 snprintf(bf, sizeof(bf),
2476 "*\t%08X\t%08X\t%04X\t%d\t%u\t%d\t%08X\t%d\t%u\t%u",
2477 prefix, 0, flags, 0, 0, 0,
2480 seq_printf(seq, "%-127s\n", bf);
2487 static const struct seq_operations fib_route_seq_ops = {
2488 .start = fib_trie_seq_start,
2489 .next = fib_trie_seq_next,
2490 .stop = fib_trie_seq_stop,
2491 .show = fib_route_seq_show,
2494 static int fib_route_seq_open(struct inode *inode, struct file *file)
2496 return seq_open_net(inode, file, &fib_route_seq_ops,
2497 sizeof(struct fib_trie_iter));
2500 static const struct file_operations fib_route_fops = {
2501 .owner = THIS_MODULE,
2502 .open = fib_route_seq_open,
2504 .llseek = seq_lseek,
2505 .release = seq_release_net,
2508 int __net_init fib_proc_init(struct net *net)
2510 if (!proc_net_fops_create(net, "fib_trie", S_IRUGO, &fib_trie_fops))
2513 if (!proc_net_fops_create(net, "fib_triestat", S_IRUGO,
2514 &fib_triestat_fops))
2517 if (!proc_net_fops_create(net, "route", S_IRUGO, &fib_route_fops))
2523 proc_net_remove(net, "fib_triestat");
2525 proc_net_remove(net, "fib_trie");
2530 void __net_exit fib_proc_exit(struct net *net)
2532 proc_net_remove(net, "fib_trie");
2533 proc_net_remove(net, "fib_triestat");
2534 proc_net_remove(net, "route");
2537 #endif /* CONFIG_PROC_FS */