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)
100 unsigned long parent;
105 unsigned long parent;
107 struct hlist_head list;
112 struct hlist_node hlist;
115 struct list_head falh;
119 unsigned long parent;
121 unsigned char pos; /* 2log(KEYLENGTH) bits needed */
122 unsigned char bits; /* 2log(KEYLENGTH) bits needed */
123 unsigned int full_children; /* KEYLENGTH bits needed */
124 unsigned int 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];
152 #ifdef CONFIG_IP_FIB_TRIE_STATS
153 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(size_t size)
336 if (size <= PAGE_SIZE)
337 return kzalloc(size, 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 size_t size = sizeof(struct tnode) +
350 (sizeof(struct node *) << tn->bits);
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 size_t sz = sizeof(struct tnode) + (sizeof(struct node *) << bits);
390 struct tnode *tn = tnode_alloc(sz);
393 tn->parent = T_TNODE;
397 tn->full_children = 0;
398 tn->empty_children = 1<<bits;
401 pr_debug("AT %p s=%u %lu\n", tn, (unsigned int) sizeof(struct tnode),
402 (unsigned long) (sizeof(struct node) << bits));
407 * Check whether a tnode 'n' is "full", i.e. it is an internal node
408 * and no bits are skipped. See discussion in dyntree paper p. 6
411 static inline int tnode_full(const struct tnode *tn, const struct node *n)
413 if (n == NULL || IS_LEAF(n))
416 return ((struct tnode *) n)->pos == tn->pos + tn->bits;
419 static inline void put_child(struct trie *t, struct tnode *tn, int i, struct node *n)
421 tnode_put_child_reorg(tn, i, n, -1);
425 * Add a child at position i overwriting the old value.
426 * Update the value of full_children and empty_children.
429 static void tnode_put_child_reorg(struct tnode *tn, int i, struct node *n, int wasfull)
431 struct node *chi = tn->child[i];
434 BUG_ON(i >= 1<<tn->bits);
437 /* update emptyChildren */
438 if (n == NULL && chi != NULL)
439 tn->empty_children++;
440 else if (n != NULL && chi == NULL)
441 tn->empty_children--;
443 /* update fullChildren */
445 wasfull = tnode_full(tn, chi);
447 isfull = tnode_full(tn, n);
448 if (wasfull && !isfull)
450 else if (!wasfull && isfull)
454 node_set_parent(n, tn);
456 rcu_assign_pointer(tn->child[i], n);
459 static struct node *resize(struct trie *t, struct tnode *tn)
463 struct tnode *old_tn;
464 int inflate_threshold_use;
465 int halve_threshold_use;
471 pr_debug("In tnode_resize %p inflate_threshold=%d threshold=%d\n",
472 tn, inflate_threshold, halve_threshold);
475 if (tn->empty_children == tnode_child_length(tn)) {
480 if (tn->empty_children == tnode_child_length(tn) - 1)
481 for (i = 0; i < tnode_child_length(tn); i++) {
488 /* compress one level */
489 node_set_parent(n, NULL);
494 * Double as long as the resulting node has a number of
495 * nonempty nodes that are above the threshold.
499 * From "Implementing a dynamic compressed trie" by Stefan Nilsson of
500 * the Helsinki University of Technology and Matti Tikkanen of Nokia
501 * Telecommunications, page 6:
502 * "A node is doubled if the ratio of non-empty children to all
503 * children in the *doubled* node is at least 'high'."
505 * 'high' in this instance is the variable 'inflate_threshold'. It
506 * is expressed as a percentage, so we multiply it with
507 * tnode_child_length() and instead of multiplying by 2 (since the
508 * child array will be doubled by inflate()) and multiplying
509 * the left-hand side by 100 (to handle the percentage thing) we
510 * multiply the left-hand side by 50.
512 * The left-hand side may look a bit weird: tnode_child_length(tn)
513 * - tn->empty_children is of course the number of non-null children
514 * in the current node. tn->full_children is the number of "full"
515 * children, that is non-null tnodes with a skip value of 0.
516 * All of those will be doubled in the resulting inflated tnode, so
517 * we just count them one extra time here.
519 * A clearer way to write this would be:
521 * to_be_doubled = tn->full_children;
522 * not_to_be_doubled = tnode_child_length(tn) - tn->empty_children -
525 * new_child_length = tnode_child_length(tn) * 2;
527 * new_fill_factor = 100 * (not_to_be_doubled + 2*to_be_doubled) /
529 * if (new_fill_factor >= inflate_threshold)
531 * ...and so on, tho it would mess up the while () loop.
534 * 100 * (not_to_be_doubled + 2*to_be_doubled) / new_child_length >=
538 * 100 * (not_to_be_doubled + 2*to_be_doubled) >=
539 * inflate_threshold * new_child_length
541 * expand not_to_be_doubled and to_be_doubled, and shorten:
542 * 100 * (tnode_child_length(tn) - tn->empty_children +
543 * tn->full_children) >= inflate_threshold * new_child_length
545 * expand new_child_length:
546 * 100 * (tnode_child_length(tn) - tn->empty_children +
547 * tn->full_children) >=
548 * inflate_threshold * tnode_child_length(tn) * 2
551 * 50 * (tn->full_children + tnode_child_length(tn) -
552 * tn->empty_children) >= inflate_threshold *
553 * tnode_child_length(tn)
559 /* Keep root node larger */
562 inflate_threshold_use = inflate_threshold_root;
564 inflate_threshold_use = inflate_threshold;
568 while ((tn->full_children > 0 && max_resize-- &&
569 50 * (tn->full_children + tnode_child_length(tn) - tn->empty_children) >=
570 inflate_threshold_use * tnode_child_length(tn))) {
576 #ifdef CONFIG_IP_FIB_TRIE_STATS
577 t->stats.resize_node_skipped++;
583 if (max_resize < 0) {
585 printk(KERN_WARNING "Fix inflate_threshold_root. Now=%d size=%d bits\n",
586 inflate_threshold_root, tn->bits);
588 printk(KERN_WARNING "Fix inflate_threshold. Now=%d size=%d bits\n",
589 inflate_threshold, tn->bits);
595 * Halve as long as the number of empty children in this
596 * node is above threshold.
600 /* Keep root node larger */
603 halve_threshold_use = halve_threshold_root;
605 halve_threshold_use = halve_threshold;
609 while (tn->bits > 1 && max_resize-- &&
610 100 * (tnode_child_length(tn) - tn->empty_children) <
611 halve_threshold_use * tnode_child_length(tn)) {
617 #ifdef CONFIG_IP_FIB_TRIE_STATS
618 t->stats.resize_node_skipped++;
624 if (max_resize < 0) {
626 printk(KERN_WARNING "Fix halve_threshold_root. Now=%d size=%d bits\n",
627 halve_threshold_root, tn->bits);
629 printk(KERN_WARNING "Fix halve_threshold. Now=%d size=%d bits\n",
630 halve_threshold, tn->bits);
633 /* Only one child remains */
634 if (tn->empty_children == tnode_child_length(tn) - 1)
635 for (i = 0; i < tnode_child_length(tn); i++) {
642 /* compress one level */
644 node_set_parent(n, NULL);
649 return (struct node *) tn;
652 static struct tnode *inflate(struct trie *t, struct tnode *tn)
654 struct tnode *oldtnode = tn;
655 int olen = tnode_child_length(tn);
658 pr_debug("In inflate\n");
660 tn = tnode_new(oldtnode->key, oldtnode->pos, oldtnode->bits + 1);
663 return ERR_PTR(-ENOMEM);
666 * Preallocate and store tnodes before the actual work so we
667 * don't get into an inconsistent state if memory allocation
668 * fails. In case of failure we return the oldnode and inflate
669 * of tnode is ignored.
672 for (i = 0; i < olen; i++) {
673 struct tnode *inode = (struct tnode *) tnode_get_child(oldtnode, i);
677 inode->pos == oldtnode->pos + oldtnode->bits &&
679 struct tnode *left, *right;
680 t_key m = ~0U << (KEYLENGTH - 1) >> inode->pos;
682 left = tnode_new(inode->key&(~m), inode->pos + 1,
687 right = tnode_new(inode->key|m, inode->pos + 1,
695 put_child(t, tn, 2*i, (struct node *) left);
696 put_child(t, tn, 2*i+1, (struct node *) right);
700 for (i = 0; i < olen; i++) {
702 struct node *node = tnode_get_child(oldtnode, i);
703 struct tnode *left, *right;
710 /* A leaf or an internal node with skipped bits */
712 if (IS_LEAF(node) || ((struct tnode *) node)->pos >
713 tn->pos + tn->bits - 1) {
714 if (tkey_extract_bits(node->key, oldtnode->pos + oldtnode->bits,
716 put_child(t, tn, 2*i, node);
718 put_child(t, tn, 2*i+1, node);
722 /* An internal node with two children */
723 inode = (struct tnode *) node;
725 if (inode->bits == 1) {
726 put_child(t, tn, 2*i, inode->child[0]);
727 put_child(t, tn, 2*i+1, inode->child[1]);
733 /* An internal node with more than two children */
735 /* We will replace this node 'inode' with two new
736 * ones, 'left' and 'right', each with half of the
737 * original children. The two new nodes will have
738 * a position one bit further down the key and this
739 * means that the "significant" part of their keys
740 * (see the discussion near the top of this file)
741 * will differ by one bit, which will be "0" in
742 * left's key and "1" in right's key. Since we are
743 * moving the key position by one step, the bit that
744 * we are moving away from - the bit at position
745 * (inode->pos) - is the one that will differ between
746 * left and right. So... we synthesize that bit in the
748 * The mask 'm' below will be a single "one" bit at
749 * the position (inode->pos)
752 /* Use the old key, but set the new significant
756 left = (struct tnode *) tnode_get_child(tn, 2*i);
757 put_child(t, tn, 2*i, NULL);
761 right = (struct tnode *) tnode_get_child(tn, 2*i+1);
762 put_child(t, tn, 2*i+1, NULL);
766 size = tnode_child_length(left);
767 for (j = 0; j < size; j++) {
768 put_child(t, left, j, inode->child[j]);
769 put_child(t, right, j, inode->child[j + size]);
771 put_child(t, tn, 2*i, resize(t, left));
772 put_child(t, tn, 2*i+1, resize(t, right));
776 tnode_free(oldtnode);
780 int size = tnode_child_length(tn);
783 for (j = 0; j < size; j++)
785 tnode_free((struct tnode *)tn->child[j]);
789 return ERR_PTR(-ENOMEM);
793 static struct tnode *halve(struct trie *t, struct tnode *tn)
795 struct tnode *oldtnode = tn;
796 struct node *left, *right;
798 int olen = tnode_child_length(tn);
800 pr_debug("In halve\n");
802 tn = tnode_new(oldtnode->key, oldtnode->pos, oldtnode->bits - 1);
805 return ERR_PTR(-ENOMEM);
808 * Preallocate and store tnodes before the actual work so we
809 * don't get into an inconsistent state if memory allocation
810 * fails. In case of failure we return the oldnode and halve
811 * of tnode is ignored.
814 for (i = 0; i < olen; i += 2) {
815 left = tnode_get_child(oldtnode, i);
816 right = tnode_get_child(oldtnode, i+1);
818 /* Two nonempty children */
822 newn = tnode_new(left->key, tn->pos + tn->bits, 1);
827 put_child(t, tn, i/2, (struct node *)newn);
832 for (i = 0; i < olen; i += 2) {
833 struct tnode *newBinNode;
835 left = tnode_get_child(oldtnode, i);
836 right = tnode_get_child(oldtnode, i+1);
838 /* At least one of the children is empty */
840 if (right == NULL) /* Both are empty */
842 put_child(t, tn, i/2, right);
847 put_child(t, tn, i/2, left);
851 /* Two nonempty children */
852 newBinNode = (struct tnode *) tnode_get_child(tn, i/2);
853 put_child(t, tn, i/2, NULL);
854 put_child(t, newBinNode, 0, left);
855 put_child(t, newBinNode, 1, right);
856 put_child(t, tn, i/2, resize(t, newBinNode));
858 tnode_free(oldtnode);
862 int size = tnode_child_length(tn);
865 for (j = 0; j < size; j++)
867 tnode_free((struct tnode *)tn->child[j]);
871 return ERR_PTR(-ENOMEM);
875 /* readside must use rcu_read_lock currently dump routines
876 via get_fa_head and dump */
878 static struct leaf_info *find_leaf_info(struct leaf *l, int plen)
880 struct hlist_head *head = &l->list;
881 struct hlist_node *node;
882 struct leaf_info *li;
884 hlist_for_each_entry_rcu(li, node, head, hlist)
885 if (li->plen == plen)
891 static inline struct list_head * get_fa_head(struct leaf *l, int plen)
893 struct leaf_info *li = find_leaf_info(l, plen);
901 static void insert_leaf_info(struct hlist_head *head, struct leaf_info *new)
903 struct leaf_info *li = NULL, *last = NULL;
904 struct hlist_node *node;
906 if (hlist_empty(head)) {
907 hlist_add_head_rcu(&new->hlist, head);
909 hlist_for_each_entry(li, node, head, hlist) {
910 if (new->plen > li->plen)
916 hlist_add_after_rcu(&last->hlist, &new->hlist);
918 hlist_add_before_rcu(&new->hlist, &li->hlist);
922 /* rcu_read_lock needs to be hold by caller from readside */
925 fib_find_node(struct trie *t, u32 key)
932 n = rcu_dereference(t->trie);
934 while (n != NULL && NODE_TYPE(n) == T_TNODE) {
935 tn = (struct tnode *) n;
939 if (tkey_sub_equals(tn->key, pos, tn->pos-pos, key)) {
940 pos = tn->pos + tn->bits;
941 n = tnode_get_child(tn, tkey_extract_bits(key, tn->pos, tn->bits));
945 /* Case we have found a leaf. Compare prefixes */
947 if (n != NULL && IS_LEAF(n) && tkey_equals(key, n->key))
948 return (struct leaf *)n;
953 static struct node *trie_rebalance(struct trie *t, struct tnode *tn)
956 t_key cindex, key = tn->key;
959 while (tn != NULL && (tp = node_parent((struct node *)tn)) != NULL) {
960 cindex = tkey_extract_bits(key, tp->pos, tp->bits);
961 wasfull = tnode_full(tp, tnode_get_child(tp, cindex));
962 tn = (struct tnode *) resize (t, (struct tnode *)tn);
963 tnode_put_child_reorg((struct tnode *)tp, cindex,(struct node*)tn, wasfull);
965 tp = node_parent((struct node *) tn);
971 /* Handle last (top) tnode */
973 tn = (struct tnode*) resize(t, (struct tnode *)tn);
975 return (struct node*) tn;
978 /* only used from updater-side */
980 static struct list_head *fib_insert_node(struct trie *t, u32 key, int plen)
983 struct tnode *tp = NULL, *tn = NULL;
987 struct list_head *fa_head = NULL;
988 struct leaf_info *li;
994 /* If we point to NULL, stop. Either the tree is empty and we should
995 * just put a new leaf in if, or we have reached an empty child slot,
996 * and we should just put our new leaf in that.
997 * If we point to a T_TNODE, check if it matches our key. Note that
998 * a T_TNODE might be skipping any number of bits - its 'pos' need
999 * not be the parent's 'pos'+'bits'!
1001 * If it does match the current key, get pos/bits from it, extract
1002 * the index from our key, push the T_TNODE and walk the tree.
1004 * If it doesn't, we have to replace it with a new T_TNODE.
1006 * If we point to a T_LEAF, it might or might not have the same key
1007 * as we do. If it does, just change the value, update the T_LEAF's
1008 * value, and return it.
1009 * If it doesn't, we need to replace it with a T_TNODE.
1012 while (n != NULL && NODE_TYPE(n) == T_TNODE) {
1013 tn = (struct tnode *) n;
1017 if (tkey_sub_equals(tn->key, pos, tn->pos-pos, key)) {
1019 pos = tn->pos + tn->bits;
1020 n = tnode_get_child(tn, tkey_extract_bits(key, tn->pos, tn->bits));
1022 BUG_ON(n && node_parent(n) != tn);
1028 * n ----> NULL, LEAF or TNODE
1030 * tp is n's (parent) ----> NULL or TNODE
1033 BUG_ON(tp && IS_LEAF(tp));
1035 /* Case 1: n is a leaf. Compare prefixes */
1037 if (n != NULL && IS_LEAF(n) && tkey_equals(key, n->key)) {
1038 l = (struct leaf *) n;
1039 li = leaf_info_new(plen);
1044 fa_head = &li->falh;
1045 insert_leaf_info(&l->list, li);
1054 li = leaf_info_new(plen);
1057 tnode_free((struct tnode *) l);
1061 fa_head = &li->falh;
1062 insert_leaf_info(&l->list, li);
1064 if (t->trie && n == NULL) {
1065 /* Case 2: n is NULL, and will just insert a new leaf */
1067 node_set_parent((struct node *)l, tp);
1069 cindex = tkey_extract_bits(key, tp->pos, tp->bits);
1070 put_child(t, (struct tnode *)tp, cindex, (struct node *)l);
1072 /* Case 3: n is a LEAF or a TNODE and the key doesn't match. */
1074 * Add a new tnode here
1075 * first tnode need some special handling
1079 pos = tp->pos+tp->bits;
1084 newpos = tkey_mismatch(key, pos, n->key);
1085 tn = tnode_new(n->key, newpos, 1);
1088 tn = tnode_new(key, newpos, 1); /* First tnode */
1093 tnode_free((struct tnode *) l);
1097 node_set_parent((struct node *)tn, tp);
1099 missbit = tkey_extract_bits(key, newpos, 1);
1100 put_child(t, tn, missbit, (struct node *)l);
1101 put_child(t, tn, 1-missbit, n);
1104 cindex = tkey_extract_bits(key, tp->pos, tp->bits);
1105 put_child(t, (struct tnode *)tp, cindex, (struct node *)tn);
1107 rcu_assign_pointer(t->trie, (struct node *)tn); /* First tnode */
1112 if (tp && tp->pos + tp->bits > 32)
1113 printk(KERN_WARNING "fib_trie tp=%p pos=%d, bits=%d, key=%0x plen=%d\n",
1114 tp, tp->pos, tp->bits, key, plen);
1116 /* Rebalance the trie */
1118 rcu_assign_pointer(t->trie, trie_rebalance(t, tp));
1124 * Caller must hold RTNL.
1126 static int fn_trie_insert(struct fib_table *tb, struct fib_config *cfg)
1128 struct trie *t = (struct trie *) tb->tb_data;
1129 struct fib_alias *fa, *new_fa;
1130 struct list_head *fa_head = NULL;
1131 struct fib_info *fi;
1132 int plen = cfg->fc_dst_len;
1133 u8 tos = cfg->fc_tos;
1141 key = ntohl(cfg->fc_dst);
1143 pr_debug("Insert table=%u %08x/%d\n", tb->tb_id, key, plen);
1145 mask = ntohl(inet_make_mask(plen));
1152 fi = fib_create_info(cfg);
1158 l = fib_find_node(t, key);
1162 fa_head = get_fa_head(l, plen);
1163 fa = fib_find_alias(fa_head, tos, fi->fib_priority);
1166 /* Now fa, if non-NULL, points to the first fib alias
1167 * with the same keys [prefix,tos,priority], if such key already
1168 * exists or to the node before which we will insert new one.
1170 * If fa is NULL, we will need to allocate a new one and
1171 * insert to the head of f.
1173 * If f is NULL, no fib node matched the destination key
1174 * and we need to allocate a new one of those as well.
1177 if (fa && fa->fa_info->fib_priority == fi->fib_priority) {
1178 struct fib_alias *fa_orig;
1181 if (cfg->fc_nlflags & NLM_F_EXCL)
1184 if (cfg->fc_nlflags & NLM_F_REPLACE) {
1185 struct fib_info *fi_drop;
1188 if (fi->fib_treeref > 1)
1192 new_fa = kmem_cache_alloc(fn_alias_kmem, GFP_KERNEL);
1196 fi_drop = fa->fa_info;
1197 new_fa->fa_tos = fa->fa_tos;
1198 new_fa->fa_info = fi;
1199 new_fa->fa_type = cfg->fc_type;
1200 new_fa->fa_scope = cfg->fc_scope;
1201 state = fa->fa_state;
1202 new_fa->fa_state &= ~FA_S_ACCESSED;
1204 list_replace_rcu(&fa->fa_list, &new_fa->fa_list);
1205 alias_free_mem_rcu(fa);
1207 fib_release_info(fi_drop);
1208 if (state & FA_S_ACCESSED)
1210 rtmsg_fib(RTM_NEWROUTE, htonl(key), new_fa, plen,
1211 tb->tb_id, &cfg->fc_nlinfo, NLM_F_REPLACE);
1215 /* Error if we find a perfect match which
1216 * uses the same scope, type, and nexthop
1220 list_for_each_entry(fa, fa_orig->fa_list.prev, fa_list) {
1221 if (fa->fa_tos != tos)
1223 if (fa->fa_info->fib_priority != fi->fib_priority)
1225 if (fa->fa_type == cfg->fc_type &&
1226 fa->fa_scope == cfg->fc_scope &&
1227 fa->fa_info == fi) {
1231 if (!(cfg->fc_nlflags & NLM_F_APPEND))
1235 if (!(cfg->fc_nlflags & NLM_F_CREATE))
1239 new_fa = kmem_cache_alloc(fn_alias_kmem, GFP_KERNEL);
1243 new_fa->fa_info = fi;
1244 new_fa->fa_tos = tos;
1245 new_fa->fa_type = cfg->fc_type;
1246 new_fa->fa_scope = cfg->fc_scope;
1247 new_fa->fa_state = 0;
1249 * Insert new entry to the list.
1253 fa_head = fib_insert_node(t, key, plen);
1254 if (unlikely(!fa_head)) {
1256 goto out_free_new_fa;
1260 list_add_tail_rcu(&new_fa->fa_list,
1261 (fa ? &fa->fa_list : fa_head));
1266 rtmsg_fib(RTM_NEWROUTE, htonl(key), new_fa, plen, tb->tb_id,
1267 &cfg->fc_nlinfo, 0);
1272 kmem_cache_free(fn_alias_kmem, new_fa);
1274 fib_release_info(fi);
1280 /* should be called with rcu_read_lock */
1281 static inline int check_leaf(struct trie *t, struct leaf *l,
1282 t_key key, int *plen, const struct flowi *flp,
1283 struct fib_result *res)
1287 struct leaf_info *li;
1288 struct hlist_head *hhead = &l->list;
1289 struct hlist_node *node;
1291 hlist_for_each_entry_rcu(li, node, hhead, hlist) {
1293 mask = inet_make_mask(i);
1294 if (l->key != (key & ntohl(mask)))
1297 if ((err = fib_semantic_match(&li->falh, flp, res, htonl(l->key), mask, i)) <= 0) {
1299 #ifdef CONFIG_IP_FIB_TRIE_STATS
1300 t->stats.semantic_match_passed++;
1304 #ifdef CONFIG_IP_FIB_TRIE_STATS
1305 t->stats.semantic_match_miss++;
1312 fn_trie_lookup(struct fib_table *tb, const struct flowi *flp, struct fib_result *res)
1314 struct trie *t = (struct trie *) tb->tb_data;
1319 t_key key = ntohl(flp->fl4_dst);
1322 int current_prefix_length = KEYLENGTH;
1324 t_key node_prefix, key_prefix, pref_mismatch;
1329 n = rcu_dereference(t->trie);
1333 #ifdef CONFIG_IP_FIB_TRIE_STATS
1339 if ((ret = check_leaf(t, (struct leaf *)n, key, &plen, flp, res)) <= 0)
1343 pn = (struct tnode *) n;
1351 cindex = tkey_extract_bits(mask_pfx(key, current_prefix_length),
1354 n = tnode_get_child(pn, cindex);
1357 #ifdef CONFIG_IP_FIB_TRIE_STATS
1358 t->stats.null_node_hit++;
1364 if ((ret = check_leaf(t, (struct leaf *)n, key, &plen, flp, res)) <= 0)
1372 cn = (struct tnode *)n;
1375 * It's a tnode, and we can do some extra checks here if we
1376 * like, to avoid descending into a dead-end branch.
1377 * This tnode is in the parent's child array at index
1378 * key[p_pos..p_pos+p_bits] but potentially with some bits
1379 * chopped off, so in reality the index may be just a
1380 * subprefix, padded with zero at the end.
1381 * We can also take a look at any skipped bits in this
1382 * tnode - everything up to p_pos is supposed to be ok,
1383 * and the non-chopped bits of the index (se previous
1384 * paragraph) are also guaranteed ok, but the rest is
1385 * considered unknown.
1387 * The skipped bits are key[pos+bits..cn->pos].
1390 /* If current_prefix_length < pos+bits, we are already doing
1391 * actual prefix matching, which means everything from
1392 * pos+(bits-chopped_off) onward must be zero along some
1393 * branch of this subtree - otherwise there is *no* valid
1394 * prefix present. Here we can only check the skipped
1395 * bits. Remember, since we have already indexed into the
1396 * parent's child array, we know that the bits we chopped of
1400 /* NOTA BENE: CHECKING ONLY SKIPPED BITS FOR THE NEW NODE HERE */
1402 if (current_prefix_length < pos+bits) {
1403 if (tkey_extract_bits(cn->key, current_prefix_length,
1404 cn->pos - current_prefix_length) != 0 ||
1410 * If chopped_off=0, the index is fully validated and we
1411 * only need to look at the skipped bits for this, the new,
1412 * tnode. What we actually want to do is to find out if
1413 * these skipped bits match our key perfectly, or if we will
1414 * have to count on finding a matching prefix further down,
1415 * because if we do, we would like to have some way of
1416 * verifying the existence of such a prefix at this point.
1419 /* The only thing we can do at this point is to verify that
1420 * any such matching prefix can indeed be a prefix to our
1421 * key, and if the bits in the node we are inspecting that
1422 * do not match our key are not ZERO, this cannot be true.
1423 * Thus, find out where there is a mismatch (before cn->pos)
1424 * and verify that all the mismatching bits are zero in the
1428 /* Note: We aren't very concerned about the piece of the key
1429 * that precede pn->pos+pn->bits, since these have already been
1430 * checked. The bits after cn->pos aren't checked since these are
1431 * by definition "unknown" at this point. Thus, what we want to
1432 * see is if we are about to enter the "prefix matching" state,
1433 * and in that case verify that the skipped bits that will prevail
1434 * throughout this subtree are zero, as they have to be if we are
1435 * to find a matching prefix.
1438 node_prefix = mask_pfx(cn->key, cn->pos);
1439 key_prefix = mask_pfx(key, cn->pos);
1440 pref_mismatch = key_prefix^node_prefix;
1443 /* In short: If skipped bits in this node do not match the search
1444 * key, enter the "prefix matching" state.directly.
1446 if (pref_mismatch) {
1447 while (!(pref_mismatch & (1<<(KEYLENGTH-1)))) {
1449 pref_mismatch = pref_mismatch <<1;
1451 key_prefix = tkey_extract_bits(cn->key, mp, cn->pos-mp);
1453 if (key_prefix != 0)
1456 if (current_prefix_length >= cn->pos)
1457 current_prefix_length = mp;
1460 pn = (struct tnode *)n; /* Descend */
1467 /* As zero don't change the child key (cindex) */
1468 while ((chopped_off <= pn->bits) && !(cindex & (1<<(chopped_off-1))))
1471 /* Decrease current_... with bits chopped off */
1472 if (current_prefix_length > pn->pos + pn->bits - chopped_off)
1473 current_prefix_length = pn->pos + pn->bits - chopped_off;
1476 * Either we do the actual chop off according or if we have
1477 * chopped off all bits in this tnode walk up to our parent.
1480 if (chopped_off <= pn->bits) {
1481 cindex &= ~(1 << (chopped_off-1));
1483 struct tnode *parent = node_parent((struct node *) pn);
1487 /* Get Child's index */
1488 cindex = tkey_extract_bits(pn->key, parent->pos, parent->bits);
1492 #ifdef CONFIG_IP_FIB_TRIE_STATS
1493 t->stats.backtrack++;
1505 /* only called from updater side */
1506 static int trie_leaf_remove(struct trie *t, t_key key)
1509 struct tnode *tp = NULL;
1510 struct node *n = t->trie;
1513 pr_debug("entering trie_leaf_remove(%p)\n", n);
1515 /* Note that in the case skipped bits, those bits are *not* checked!
1516 * When we finish this, we will have NULL or a T_LEAF, and the
1517 * T_LEAF may or may not match our key.
1520 while (n != NULL && IS_TNODE(n)) {
1521 struct tnode *tn = (struct tnode *) n;
1523 n = tnode_get_child(tn ,tkey_extract_bits(key, tn->pos, tn->bits));
1525 BUG_ON(n && node_parent(n) != tn);
1527 l = (struct leaf *) n;
1529 if (!n || !tkey_equals(l->key, key))
1534 * Remove the leaf and rebalance the tree
1539 tp = node_parent(n);
1540 tnode_free((struct tnode *) n);
1543 cindex = tkey_extract_bits(key, tp->pos, tp->bits);
1544 put_child(t, (struct tnode *)tp, cindex, NULL);
1545 rcu_assign_pointer(t->trie, trie_rebalance(t, tp));
1547 rcu_assign_pointer(t->trie, NULL);
1553 * Caller must hold RTNL.
1555 static int fn_trie_delete(struct fib_table *tb, struct fib_config *cfg)
1557 struct trie *t = (struct trie *) tb->tb_data;
1559 int plen = cfg->fc_dst_len;
1560 u8 tos = cfg->fc_tos;
1561 struct fib_alias *fa, *fa_to_delete;
1562 struct list_head *fa_head;
1564 struct leaf_info *li;
1569 key = ntohl(cfg->fc_dst);
1570 mask = ntohl(inet_make_mask(plen));
1576 l = fib_find_node(t, key);
1581 fa_head = get_fa_head(l, plen);
1582 fa = fib_find_alias(fa_head, tos, 0);
1587 pr_debug("Deleting %08x/%d tos=%d t=%p\n", key, plen, tos, t);
1589 fa_to_delete = NULL;
1590 fa_head = fa->fa_list.prev;
1592 list_for_each_entry(fa, fa_head, fa_list) {
1593 struct fib_info *fi = fa->fa_info;
1595 if (fa->fa_tos != tos)
1598 if ((!cfg->fc_type || fa->fa_type == cfg->fc_type) &&
1599 (cfg->fc_scope == RT_SCOPE_NOWHERE ||
1600 fa->fa_scope == cfg->fc_scope) &&
1601 (!cfg->fc_protocol ||
1602 fi->fib_protocol == cfg->fc_protocol) &&
1603 fib_nh_match(cfg, fi) == 0) {
1613 rtmsg_fib(RTM_DELROUTE, htonl(key), fa, plen, tb->tb_id,
1614 &cfg->fc_nlinfo, 0);
1616 l = fib_find_node(t, key);
1617 li = find_leaf_info(l, plen);
1619 list_del_rcu(&fa->fa_list);
1621 if (list_empty(fa_head)) {
1622 hlist_del_rcu(&li->hlist);
1626 if (hlist_empty(&l->list))
1627 trie_leaf_remove(t, key);
1629 if (fa->fa_state & FA_S_ACCESSED)
1632 fib_release_info(fa->fa_info);
1633 alias_free_mem_rcu(fa);
1637 static int trie_flush_list(struct trie *t, struct list_head *head)
1639 struct fib_alias *fa, *fa_node;
1642 list_for_each_entry_safe(fa, fa_node, head, fa_list) {
1643 struct fib_info *fi = fa->fa_info;
1645 if (fi && (fi->fib_flags & RTNH_F_DEAD)) {
1646 list_del_rcu(&fa->fa_list);
1647 fib_release_info(fa->fa_info);
1648 alias_free_mem_rcu(fa);
1655 static int trie_flush_leaf(struct trie *t, struct leaf *l)
1658 struct hlist_head *lih = &l->list;
1659 struct hlist_node *node, *tmp;
1660 struct leaf_info *li = NULL;
1662 hlist_for_each_entry_safe(li, node, tmp, lih, hlist) {
1663 found += trie_flush_list(t, &li->falh);
1665 if (list_empty(&li->falh)) {
1666 hlist_del_rcu(&li->hlist);
1673 /* rcu_read_lock needs to be hold by caller from readside */
1675 static struct leaf *nextleaf(struct trie *t, struct leaf *thisleaf)
1677 struct node *c = (struct node *) thisleaf;
1680 struct node *trie = rcu_dereference(t->trie);
1686 if (IS_LEAF(trie)) /* trie w. just a leaf */
1687 return (struct leaf *) trie;
1689 p = (struct tnode*) trie; /* Start */
1696 /* Find the next child of the parent */
1698 pos = 1 + tkey_extract_bits(c->key, p->pos, p->bits);
1702 last = 1 << p->bits;
1703 for (idx = pos; idx < last ; idx++) {
1704 c = rcu_dereference(p->child[idx]);
1709 /* Decend if tnode */
1710 while (IS_TNODE(c)) {
1711 p = (struct tnode *) c;
1714 /* Rightmost non-NULL branch */
1715 if (p && IS_TNODE(p))
1716 while (!(c = rcu_dereference(p->child[idx]))
1717 && idx < (1<<p->bits)) idx++;
1719 /* Done with this tnode? */
1720 if (idx >= (1 << p->bits) || !c)
1723 return (struct leaf *) c;
1726 /* No more children go up one step */
1727 c = (struct node *) p;
1730 return NULL; /* Ready. Root of trie */
1734 * Caller must hold RTNL.
1736 static int fn_trie_flush(struct fib_table *tb)
1738 struct trie *t = (struct trie *) tb->tb_data;
1739 struct leaf *ll = NULL, *l = NULL;
1742 for (h = 0; (l = nextleaf(t, l)) != NULL; h++) {
1743 found += trie_flush_leaf(t, l);
1745 if (ll && hlist_empty(&ll->list))
1746 trie_leaf_remove(t, ll->key);
1750 if (ll && hlist_empty(&ll->list))
1751 trie_leaf_remove(t, ll->key);
1753 pr_debug("trie_flush found=%d\n", found);
1758 fn_trie_select_default(struct fib_table *tb, const struct flowi *flp, struct fib_result *res)
1760 struct trie *t = (struct trie *) tb->tb_data;
1761 int order, last_idx;
1762 struct fib_info *fi = NULL;
1763 struct fib_info *last_resort;
1764 struct fib_alias *fa = NULL;
1765 struct list_head *fa_head;
1774 l = fib_find_node(t, 0);
1778 fa_head = get_fa_head(l, 0);
1782 if (list_empty(fa_head))
1785 list_for_each_entry_rcu(fa, fa_head, fa_list) {
1786 struct fib_info *next_fi = fa->fa_info;
1788 if (fa->fa_scope != res->scope ||
1789 fa->fa_type != RTN_UNICAST)
1792 if (next_fi->fib_priority > res->fi->fib_priority)
1794 if (!next_fi->fib_nh[0].nh_gw ||
1795 next_fi->fib_nh[0].nh_scope != RT_SCOPE_LINK)
1797 fa->fa_state |= FA_S_ACCESSED;
1800 if (next_fi != res->fi)
1802 } else if (!fib_detect_death(fi, order, &last_resort,
1803 &last_idx, tb->tb_default)) {
1804 fib_result_assign(res, fi);
1805 tb->tb_default = order;
1811 if (order <= 0 || fi == NULL) {
1812 tb->tb_default = -1;
1816 if (!fib_detect_death(fi, order, &last_resort, &last_idx,
1818 fib_result_assign(res, fi);
1819 tb->tb_default = order;
1823 fib_result_assign(res, last_resort);
1824 tb->tb_default = last_idx;
1829 static int fn_trie_dump_fa(t_key key, int plen, struct list_head *fah, struct fib_table *tb,
1830 struct sk_buff *skb, struct netlink_callback *cb)
1833 struct fib_alias *fa;
1835 __be32 xkey = htonl(key);
1840 /* rcu_read_lock is hold by caller */
1842 list_for_each_entry_rcu(fa, fah, fa_list) {
1847 BUG_ON(!fa->fa_info);
1849 if (fib_dump_info(skb, NETLINK_CB(cb->skb).pid,
1858 fa->fa_info, 0) < 0) {
1868 static int fn_trie_dump_plen(struct trie *t, int plen, struct fib_table *tb, struct sk_buff *skb,
1869 struct netlink_callback *cb)
1872 struct list_head *fa_head;
1873 struct leaf *l = NULL;
1877 for (h = 0; (l = nextleaf(t, l)) != NULL; h++) {
1881 memset(&cb->args[4], 0,
1882 sizeof(cb->args) - 4*sizeof(cb->args[0]));
1884 fa_head = get_fa_head(l, plen);
1889 if (list_empty(fa_head))
1892 if (fn_trie_dump_fa(l->key, plen, fa_head, tb, skb, cb)<0) {
1901 static int fn_trie_dump(struct fib_table *tb, struct sk_buff *skb, struct netlink_callback *cb)
1904 struct trie *t = (struct trie *) tb->tb_data;
1909 for (m = 0; m <= 32; m++) {
1913 memset(&cb->args[3], 0,
1914 sizeof(cb->args) - 3*sizeof(cb->args[0]));
1916 if (fn_trie_dump_plen(t, 32-m, tb, skb, cb)<0) {
1929 void __init fib_hash_init(void)
1931 fn_alias_kmem = kmem_cache_create("ip_fib_alias", sizeof(struct fib_alias),
1932 0, SLAB_HWCACHE_ALIGN|SLAB_PANIC, NULL);
1936 /* Fix more generic FIB names for init later */
1937 struct fib_table *fib_hash_table(u32 id)
1939 struct fib_table *tb;
1942 tb = kmalloc(sizeof(struct fib_table) + sizeof(struct trie),
1948 tb->tb_default = -1;
1949 tb->tb_lookup = fn_trie_lookup;
1950 tb->tb_insert = fn_trie_insert;
1951 tb->tb_delete = fn_trie_delete;
1952 tb->tb_flush = fn_trie_flush;
1953 tb->tb_select_default = fn_trie_select_default;
1954 tb->tb_dump = fn_trie_dump;
1956 t = (struct trie *) tb->tb_data;
1957 memset(t, 0, sizeof(*t));
1959 if (id == RT_TABLE_LOCAL)
1960 printk(KERN_INFO "IPv4 FIB: Using LC-trie version %s\n", VERSION);
1965 #ifdef CONFIG_PROC_FS
1966 /* Depth first Trie walk iterator */
1967 struct fib_trie_iter {
1968 struct seq_net_private p;
1969 struct trie *trie_local, *trie_main;
1970 struct tnode *tnode;
1976 static struct node *fib_trie_get_next(struct fib_trie_iter *iter)
1978 struct tnode *tn = iter->tnode;
1979 unsigned cindex = iter->index;
1982 /* A single entry routing table */
1986 pr_debug("get_next iter={node=%p index=%d depth=%d}\n",
1987 iter->tnode, iter->index, iter->depth);
1989 while (cindex < (1<<tn->bits)) {
1990 struct node *n = tnode_get_child(tn, cindex);
1995 iter->index = cindex + 1;
1997 /* push down one level */
1998 iter->tnode = (struct tnode *) n;
2008 /* Current node exhausted, pop back up */
2009 p = node_parent((struct node *)tn);
2011 cindex = tkey_extract_bits(tn->key, p->pos, p->bits)+1;
2021 static struct node *fib_trie_get_first(struct fib_trie_iter *iter,
2029 n = rcu_dereference(t->trie);
2036 iter->tnode = (struct tnode *) n;
2051 static void trie_collect_stats(struct trie *t, struct trie_stat *s)
2054 struct fib_trie_iter iter;
2056 memset(s, 0, sizeof(*s));
2059 for (n = fib_trie_get_first(&iter, t); n;
2060 n = fib_trie_get_next(&iter)) {
2063 s->totdepth += iter.depth;
2064 if (iter.depth > s->maxdepth)
2065 s->maxdepth = iter.depth;
2067 const struct tnode *tn = (const struct tnode *) n;
2071 if (tn->bits < MAX_STAT_DEPTH)
2072 s->nodesizes[tn->bits]++;
2074 for (i = 0; i < (1<<tn->bits); i++)
2083 * This outputs /proc/net/fib_triestats
2085 static void trie_show_stats(struct seq_file *seq, struct trie_stat *stat)
2087 unsigned i, max, pointers, bytes, avdepth;
2090 avdepth = stat->totdepth*100 / stat->leaves;
2094 seq_printf(seq, "\tAver depth: %u.%02d\n", avdepth / 100, avdepth % 100 );
2095 seq_printf(seq, "\tMax depth: %u\n", stat->maxdepth);
2097 seq_printf(seq, "\tLeaves: %u\n", stat->leaves);
2099 bytes = sizeof(struct leaf) * stat->leaves;
2100 seq_printf(seq, "\tInternal nodes: %u\n\t", stat->tnodes);
2101 bytes += sizeof(struct tnode) * stat->tnodes;
2103 max = MAX_STAT_DEPTH;
2104 while (max > 0 && stat->nodesizes[max-1] == 0)
2108 for (i = 1; i <= max; i++)
2109 if (stat->nodesizes[i] != 0) {
2110 seq_printf(seq, " %u: %u", i, stat->nodesizes[i]);
2111 pointers += (1<<i) * stat->nodesizes[i];
2113 seq_putc(seq, '\n');
2114 seq_printf(seq, "\tPointers: %u\n", pointers);
2116 bytes += sizeof(struct node *) * pointers;
2117 seq_printf(seq, "Null ptrs: %u\n", stat->nullpointers);
2118 seq_printf(seq, "Total size: %u kB\n", (bytes + 1023) / 1024);
2121 #ifdef CONFIG_IP_FIB_TRIE_STATS
2122 static void trie_show_usage(struct seq_file *seq,
2123 const struct trie_use_stats *stats)
2125 seq_printf(seq, "\nCounters:\n---------\n");
2126 seq_printf(seq,"gets = %u\n", stats->gets);
2127 seq_printf(seq,"backtracks = %u\n", stats->backtrack);
2128 seq_printf(seq,"semantic match passed = %u\n", stats->semantic_match_passed);
2129 seq_printf(seq,"semantic match miss = %u\n", stats->semantic_match_miss);
2130 seq_printf(seq,"null node hit= %u\n", stats->null_node_hit);
2131 seq_printf(seq,"skipped node resize = %u\n\n", stats->resize_node_skipped);
2133 #endif /* CONFIG_IP_FIB_TRIE_STATS */
2135 static void fib_trie_show(struct seq_file *seq, const char *name, struct trie *trie)
2137 struct trie_stat stat;
2139 seq_printf(seq, "%s: %d\n", name, trie->size);
2140 trie_collect_stats(trie, &stat);
2141 trie_show_stats(seq, &stat);
2142 #ifdef CONFIG_IP_FIB_TRIE_STATS
2143 trie_show_usage(seq, &trie->stats);
2147 static int fib_triestat_seq_show(struct seq_file *seq, void *v)
2149 struct net *net = (struct net *)seq->private;
2150 struct fib_table *tb;
2153 "Basic info: size of leaf: %Zd bytes, size of tnode: %Zd bytes.\n",
2154 sizeof(struct leaf), sizeof(struct tnode));
2156 tb = fib_get_table(net, RT_TABLE_LOCAL);
2158 fib_trie_show(seq, "Local", (struct trie *) tb->tb_data);
2160 tb = fib_get_table(net, RT_TABLE_MAIN);
2162 fib_trie_show(seq, "Main", (struct trie *) tb->tb_data);
2167 static int fib_triestat_seq_open(struct inode *inode, struct file *file)
2172 net = get_proc_net(inode);
2175 err = single_open(file, fib_triestat_seq_show, net);
2183 static int fib_triestat_seq_release(struct inode *ino, struct file *f)
2185 struct seq_file *seq = f->private_data;
2186 put_net(seq->private);
2187 return single_release(ino, f);
2190 static const struct file_operations fib_triestat_fops = {
2191 .owner = THIS_MODULE,
2192 .open = fib_triestat_seq_open,
2194 .llseek = seq_lseek,
2195 .release = fib_triestat_seq_release,
2198 static struct node *fib_trie_get_idx(struct fib_trie_iter *iter,
2204 for (n = fib_trie_get_first(iter, iter->trie_local);
2205 n; ++idx, n = fib_trie_get_next(iter)) {
2210 for (n = fib_trie_get_first(iter, iter->trie_main);
2211 n; ++idx, n = fib_trie_get_next(iter)) {
2218 static void *fib_trie_seq_start(struct seq_file *seq, loff_t *pos)
2221 struct fib_trie_iter *iter = seq->private;
2222 struct fib_table *tb;
2224 if (!iter->trie_local) {
2225 tb = fib_get_table(iter->p.net, RT_TABLE_LOCAL);
2227 iter->trie_local = (struct trie *) tb->tb_data;
2229 if (!iter->trie_main) {
2230 tb = fib_get_table(iter->p.net, RT_TABLE_MAIN);
2232 iter->trie_main = (struct trie *) tb->tb_data;
2236 return SEQ_START_TOKEN;
2237 return fib_trie_get_idx(iter, *pos - 1);
2240 static void *fib_trie_seq_next(struct seq_file *seq, void *v, loff_t *pos)
2242 struct fib_trie_iter *iter = seq->private;
2246 if (v == SEQ_START_TOKEN)
2247 return fib_trie_get_idx(iter, 0);
2249 v = fib_trie_get_next(iter);
2254 /* continue scan in next trie */
2255 if (iter->trie == iter->trie_local)
2256 return fib_trie_get_first(iter, iter->trie_main);
2261 static void fib_trie_seq_stop(struct seq_file *seq, void *v)
2267 static void seq_indent(struct seq_file *seq, int n)
2269 while (n-- > 0) seq_puts(seq, " ");
2272 static inline const char *rtn_scope(char *buf, size_t len, enum rt_scope_t s)
2275 case RT_SCOPE_UNIVERSE: return "universe";
2276 case RT_SCOPE_SITE: return "site";
2277 case RT_SCOPE_LINK: return "link";
2278 case RT_SCOPE_HOST: return "host";
2279 case RT_SCOPE_NOWHERE: return "nowhere";
2281 snprintf(buf, len, "scope=%d", s);
2286 static const char *rtn_type_names[__RTN_MAX] = {
2287 [RTN_UNSPEC] = "UNSPEC",
2288 [RTN_UNICAST] = "UNICAST",
2289 [RTN_LOCAL] = "LOCAL",
2290 [RTN_BROADCAST] = "BROADCAST",
2291 [RTN_ANYCAST] = "ANYCAST",
2292 [RTN_MULTICAST] = "MULTICAST",
2293 [RTN_BLACKHOLE] = "BLACKHOLE",
2294 [RTN_UNREACHABLE] = "UNREACHABLE",
2295 [RTN_PROHIBIT] = "PROHIBIT",
2296 [RTN_THROW] = "THROW",
2298 [RTN_XRESOLVE] = "XRESOLVE",
2301 static inline const char *rtn_type(char *buf, size_t len, unsigned t)
2303 if (t < __RTN_MAX && rtn_type_names[t])
2304 return rtn_type_names[t];
2305 snprintf(buf, len, "type %u", t);
2309 /* Pretty print the trie */
2310 static int fib_trie_seq_show(struct seq_file *seq, void *v)
2312 const struct fib_trie_iter *iter = seq->private;
2315 if (v == SEQ_START_TOKEN)
2318 if (!node_parent(n)) {
2319 if (iter->trie == iter->trie_local)
2320 seq_puts(seq, "<local>:\n");
2322 seq_puts(seq, "<main>:\n");
2326 struct tnode *tn = (struct tnode *) n;
2327 __be32 prf = htonl(mask_pfx(tn->key, tn->pos));
2329 seq_indent(seq, iter->depth-1);
2330 seq_printf(seq, " +-- %d.%d.%d.%d/%d %d %d %d\n",
2331 NIPQUAD(prf), tn->pos, tn->bits, tn->full_children,
2332 tn->empty_children);
2335 struct leaf *l = (struct leaf *) n;
2337 __be32 val = htonl(l->key);
2339 seq_indent(seq, iter->depth);
2340 seq_printf(seq, " |-- %d.%d.%d.%d\n", NIPQUAD(val));
2341 for (i = 32; i >= 0; i--) {
2342 struct leaf_info *li = find_leaf_info(l, i);
2345 struct fib_alias *fa;
2347 list_for_each_entry_rcu(fa, &li->falh, fa_list) {
2348 char buf1[32], buf2[32];
2350 seq_indent(seq, iter->depth+1);
2351 seq_printf(seq, " /%d %s %s", i,
2352 rtn_scope(buf1, sizeof(buf1),
2354 rtn_type(buf2, sizeof(buf2),
2357 seq_printf(seq, "tos =%d\n",
2359 seq_putc(seq, '\n');
2368 static const struct seq_operations fib_trie_seq_ops = {
2369 .start = fib_trie_seq_start,
2370 .next = fib_trie_seq_next,
2371 .stop = fib_trie_seq_stop,
2372 .show = fib_trie_seq_show,
2375 static int fib_trie_seq_open(struct inode *inode, struct file *file)
2377 return seq_open_net(inode, file, &fib_trie_seq_ops,
2378 sizeof(struct fib_trie_iter));
2381 static const struct file_operations fib_trie_fops = {
2382 .owner = THIS_MODULE,
2383 .open = fib_trie_seq_open,
2385 .llseek = seq_lseek,
2386 .release = seq_release_net,
2389 static unsigned fib_flag_trans(int type, __be32 mask, const struct fib_info *fi)
2391 static unsigned type2flags[RTN_MAX + 1] = {
2392 [7] = RTF_REJECT, [8] = RTF_REJECT,
2394 unsigned flags = type2flags[type];
2396 if (fi && fi->fib_nh->nh_gw)
2397 flags |= RTF_GATEWAY;
2398 if (mask == htonl(0xFFFFFFFF))
2405 * This outputs /proc/net/route.
2406 * The format of the file is not supposed to be changed
2407 * and needs to be same as fib_hash output to avoid breaking
2410 static int fib_route_seq_show(struct seq_file *seq, void *v)
2412 const struct fib_trie_iter *iter = seq->private;
2417 if (v == SEQ_START_TOKEN) {
2418 seq_printf(seq, "%-127s\n", "Iface\tDestination\tGateway "
2419 "\tFlags\tRefCnt\tUse\tMetric\tMask\t\tMTU"
2424 if (iter->trie == iter->trie_local)
2429 for (i=32; i>=0; i--) {
2430 struct leaf_info *li = find_leaf_info(l, i);
2431 struct fib_alias *fa;
2432 __be32 mask, prefix;
2437 mask = inet_make_mask(li->plen);
2438 prefix = htonl(l->key);
2440 list_for_each_entry_rcu(fa, &li->falh, fa_list) {
2441 const struct fib_info *fi = fa->fa_info;
2442 unsigned flags = fib_flag_trans(fa->fa_type, mask, fi);
2444 if (fa->fa_type == RTN_BROADCAST
2445 || fa->fa_type == RTN_MULTICAST)
2449 snprintf(bf, sizeof(bf),
2450 "%s\t%08X\t%08X\t%04X\t%d\t%u\t%d\t%08X\t%d\t%u\t%u",
2451 fi->fib_dev ? fi->fib_dev->name : "*",
2453 fi->fib_nh->nh_gw, flags, 0, 0,
2456 (fi->fib_advmss ? fi->fib_advmss + 40 : 0),
2460 snprintf(bf, sizeof(bf),
2461 "*\t%08X\t%08X\t%04X\t%d\t%u\t%d\t%08X\t%d\t%u\t%u",
2462 prefix, 0, flags, 0, 0, 0,
2465 seq_printf(seq, "%-127s\n", bf);
2472 static const struct seq_operations fib_route_seq_ops = {
2473 .start = fib_trie_seq_start,
2474 .next = fib_trie_seq_next,
2475 .stop = fib_trie_seq_stop,
2476 .show = fib_route_seq_show,
2479 static int fib_route_seq_open(struct inode *inode, struct file *file)
2481 return seq_open_net(inode, file, &fib_route_seq_ops,
2482 sizeof(struct fib_trie_iter));
2485 static const struct file_operations fib_route_fops = {
2486 .owner = THIS_MODULE,
2487 .open = fib_route_seq_open,
2489 .llseek = seq_lseek,
2490 .release = seq_release_net,
2493 int __net_init fib_proc_init(struct net *net)
2495 if (!proc_net_fops_create(net, "fib_trie", S_IRUGO, &fib_trie_fops))
2498 if (!proc_net_fops_create(net, "fib_triestat", S_IRUGO,
2499 &fib_triestat_fops))
2502 if (!proc_net_fops_create(net, "route", S_IRUGO, &fib_route_fops))
2508 proc_net_remove(net, "fib_triestat");
2510 proc_net_remove(net, "fib_trie");
2515 void __net_exit fib_proc_exit(struct net *net)
2517 proc_net_remove(net, "fib_trie");
2518 proc_net_remove(net, "fib_triestat");
2519 proc_net_remove(net, "route");
2522 #endif /* CONFIG_PROC_FS */