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 prefixes;
147 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,
160 static struct node *resize(struct trie *t, struct tnode *tn);
161 static struct tnode *inflate(struct trie *t, struct tnode *tn);
162 static struct tnode *halve(struct trie *t, struct tnode *tn);
163 static void tnode_free(struct tnode *tn);
165 static struct kmem_cache *fn_alias_kmem __read_mostly;
166 static struct kmem_cache *trie_leaf_kmem __read_mostly;
168 static inline struct tnode *node_parent(struct node *node)
170 return (struct tnode *)(node->parent & ~NODE_TYPE_MASK);
173 static inline struct tnode *node_parent_rcu(struct node *node)
175 struct tnode *ret = node_parent(node);
177 return rcu_dereference(ret);
180 static inline void node_set_parent(struct node *node, struct tnode *ptr)
182 rcu_assign_pointer(node->parent,
183 (unsigned long)ptr | NODE_TYPE(node));
186 static inline struct node *tnode_get_child(struct tnode *tn, unsigned int i)
188 BUG_ON(i >= 1U << tn->bits);
193 static inline struct node *tnode_get_child_rcu(struct tnode *tn, unsigned int i)
195 struct node *ret = tnode_get_child(tn, i);
197 return rcu_dereference(ret);
200 static inline int tnode_child_length(const struct tnode *tn)
202 return 1 << tn->bits;
205 static inline t_key mask_pfx(t_key k, unsigned short l)
207 return (l == 0) ? 0 : k >> (KEYLENGTH-l) << (KEYLENGTH-l);
210 static inline t_key tkey_extract_bits(t_key a, int offset, int bits)
212 if (offset < KEYLENGTH)
213 return ((t_key)(a << offset)) >> (KEYLENGTH - bits);
218 static inline int tkey_equals(t_key a, t_key b)
223 static inline int tkey_sub_equals(t_key a, int offset, int bits, t_key b)
225 if (bits == 0 || offset >= KEYLENGTH)
227 bits = bits > KEYLENGTH ? KEYLENGTH : bits;
228 return ((a ^ b) << offset) >> (KEYLENGTH - bits) == 0;
231 static inline int tkey_mismatch(t_key a, int offset, t_key b)
238 while ((diff << i) >> (KEYLENGTH-1) == 0)
244 To understand this stuff, an understanding of keys and all their bits is
245 necessary. Every node in the trie has a key associated with it, but not
246 all of the bits in that key are significant.
248 Consider a node 'n' and its parent 'tp'.
250 If n is a leaf, every bit in its key is significant. Its presence is
251 necessitated by path compression, since during a tree traversal (when
252 searching for a leaf - unless we are doing an insertion) we will completely
253 ignore all skipped bits we encounter. Thus we need to verify, at the end of
254 a potentially successful search, that we have indeed been walking the
257 Note that we can never "miss" the correct key in the tree if present by
258 following the wrong path. Path compression ensures that segments of the key
259 that are the same for all keys with a given prefix are skipped, but the
260 skipped part *is* identical for each node in the subtrie below the skipped
261 bit! trie_insert() in this implementation takes care of that - note the
262 call to tkey_sub_equals() in trie_insert().
264 if n is an internal node - a 'tnode' here, the various parts of its key
265 have many different meanings.
268 _________________________________________________________________
269 | i | i | i | i | i | i | i | N | N | N | S | S | S | S | S | C |
270 -----------------------------------------------------------------
271 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15
273 _________________________________________________________________
274 | C | C | C | u | u | u | u | u | u | u | u | u | u | u | u | u |
275 -----------------------------------------------------------------
276 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31
283 First, let's just ignore the bits that come before the parent tp, that is
284 the bits from 0 to (tp->pos-1). They are *known* but at this point we do
285 not use them for anything.
287 The bits from (tp->pos) to (tp->pos + tp->bits - 1) - "N", above - are the
288 index into the parent's child array. That is, they will be used to find
289 'n' among tp's children.
291 The bits from (tp->pos + tp->bits) to (n->pos - 1) - "S" - are skipped bits
294 All the bits we have seen so far are significant to the node n. The rest
295 of the bits are really not needed or indeed known in n->key.
297 The bits from (n->pos) to (n->pos + n->bits - 1) - "C" - are the index into
298 n's child array, and will of course be different for each child.
301 The rest of the bits, from (n->pos + n->bits) onward, are completely unknown
306 static inline void check_tnode(const struct tnode *tn)
308 WARN_ON(tn && tn->pos+tn->bits > 32);
311 static const int halve_threshold = 25;
312 static const int inflate_threshold = 50;
313 static const int halve_threshold_root = 8;
314 static const int inflate_threshold_root = 15;
317 static void __alias_free_mem(struct rcu_head *head)
319 struct fib_alias *fa = container_of(head, struct fib_alias, rcu);
320 kmem_cache_free(fn_alias_kmem, fa);
323 static inline void alias_free_mem_rcu(struct fib_alias *fa)
325 call_rcu(&fa->rcu, __alias_free_mem);
328 static void __leaf_free_rcu(struct rcu_head *head)
330 struct leaf *l = container_of(head, struct leaf, rcu);
331 kmem_cache_free(trie_leaf_kmem, l);
334 static void __leaf_info_free_rcu(struct rcu_head *head)
336 kfree(container_of(head, struct leaf_info, rcu));
339 static inline void free_leaf_info(struct leaf_info *leaf)
341 call_rcu(&leaf->rcu, __leaf_info_free_rcu);
344 static struct tnode *tnode_alloc(size_t size)
348 if (size <= PAGE_SIZE)
349 return kzalloc(size, GFP_KERNEL);
351 pages = alloc_pages(GFP_KERNEL|__GFP_ZERO, get_order(size));
355 return page_address(pages);
358 static void __tnode_free_rcu(struct rcu_head *head)
360 struct tnode *tn = container_of(head, struct tnode, rcu);
361 size_t size = sizeof(struct tnode) +
362 (sizeof(struct node *) << tn->bits);
364 if (size <= PAGE_SIZE)
367 free_pages((unsigned long)tn, get_order(size));
370 static inline void tnode_free(struct tnode *tn)
373 struct leaf *l = (struct leaf *) tn;
374 call_rcu_bh(&l->rcu, __leaf_free_rcu);
376 call_rcu(&tn->rcu, __tnode_free_rcu);
379 static struct leaf *leaf_new(void)
381 struct leaf *l = kmem_cache_alloc(trie_leaf_kmem, GFP_KERNEL);
384 INIT_HLIST_HEAD(&l->list);
389 static struct leaf_info *leaf_info_new(int plen)
391 struct leaf_info *li = kmalloc(sizeof(struct leaf_info), GFP_KERNEL);
394 INIT_LIST_HEAD(&li->falh);
399 static struct tnode *tnode_new(t_key key, int pos, int bits)
401 size_t sz = sizeof(struct tnode) + (sizeof(struct node *) << bits);
402 struct tnode *tn = tnode_alloc(sz);
405 tn->parent = T_TNODE;
409 tn->full_children = 0;
410 tn->empty_children = 1<<bits;
413 pr_debug("AT %p s=%u %lu\n", tn, (unsigned int) sizeof(struct tnode),
414 (unsigned long) (sizeof(struct node) << bits));
419 * Check whether a tnode 'n' is "full", i.e. it is an internal node
420 * and no bits are skipped. See discussion in dyntree paper p. 6
423 static inline int tnode_full(const struct tnode *tn, const struct node *n)
425 if (n == NULL || IS_LEAF(n))
428 return ((struct tnode *) n)->pos == tn->pos + tn->bits;
431 static inline void put_child(struct trie *t, struct tnode *tn, int i,
434 tnode_put_child_reorg(tn, i, n, -1);
438 * Add a child at position i overwriting the old value.
439 * Update the value of full_children and empty_children.
442 static void tnode_put_child_reorg(struct tnode *tn, int i, struct node *n,
445 struct node *chi = tn->child[i];
448 BUG_ON(i >= 1<<tn->bits);
451 /* update emptyChildren */
452 if (n == NULL && chi != NULL)
453 tn->empty_children++;
454 else if (n != NULL && chi == NULL)
455 tn->empty_children--;
457 /* update fullChildren */
459 wasfull = tnode_full(tn, chi);
461 isfull = tnode_full(tn, n);
462 if (wasfull && !isfull)
464 else if (!wasfull && isfull)
468 node_set_parent(n, tn);
470 rcu_assign_pointer(tn->child[i], n);
473 static struct node *resize(struct trie *t, struct tnode *tn)
477 struct tnode *old_tn;
478 int inflate_threshold_use;
479 int halve_threshold_use;
485 pr_debug("In tnode_resize %p inflate_threshold=%d threshold=%d\n",
486 tn, inflate_threshold, halve_threshold);
489 if (tn->empty_children == tnode_child_length(tn)) {
494 if (tn->empty_children == tnode_child_length(tn) - 1)
495 for (i = 0; i < tnode_child_length(tn); i++) {
502 /* compress one level */
503 node_set_parent(n, NULL);
508 * Double as long as the resulting node has a number of
509 * nonempty nodes that are above the threshold.
513 * From "Implementing a dynamic compressed trie" by Stefan Nilsson of
514 * the Helsinki University of Technology and Matti Tikkanen of Nokia
515 * Telecommunications, page 6:
516 * "A node is doubled if the ratio of non-empty children to all
517 * children in the *doubled* node is at least 'high'."
519 * 'high' in this instance is the variable 'inflate_threshold'. It
520 * is expressed as a percentage, so we multiply it with
521 * tnode_child_length() and instead of multiplying by 2 (since the
522 * child array will be doubled by inflate()) and multiplying
523 * the left-hand side by 100 (to handle the percentage thing) we
524 * multiply the left-hand side by 50.
526 * The left-hand side may look a bit weird: tnode_child_length(tn)
527 * - tn->empty_children is of course the number of non-null children
528 * in the current node. tn->full_children is the number of "full"
529 * children, that is non-null tnodes with a skip value of 0.
530 * All of those will be doubled in the resulting inflated tnode, so
531 * we just count them one extra time here.
533 * A clearer way to write this would be:
535 * to_be_doubled = tn->full_children;
536 * not_to_be_doubled = tnode_child_length(tn) - tn->empty_children -
539 * new_child_length = tnode_child_length(tn) * 2;
541 * new_fill_factor = 100 * (not_to_be_doubled + 2*to_be_doubled) /
543 * if (new_fill_factor >= inflate_threshold)
545 * ...and so on, tho it would mess up the while () loop.
548 * 100 * (not_to_be_doubled + 2*to_be_doubled) / new_child_length >=
552 * 100 * (not_to_be_doubled + 2*to_be_doubled) >=
553 * inflate_threshold * new_child_length
555 * expand not_to_be_doubled and to_be_doubled, and shorten:
556 * 100 * (tnode_child_length(tn) - tn->empty_children +
557 * tn->full_children) >= inflate_threshold * new_child_length
559 * expand new_child_length:
560 * 100 * (tnode_child_length(tn) - tn->empty_children +
561 * tn->full_children) >=
562 * inflate_threshold * tnode_child_length(tn) * 2
565 * 50 * (tn->full_children + tnode_child_length(tn) -
566 * tn->empty_children) >= inflate_threshold *
567 * tnode_child_length(tn)
573 /* Keep root node larger */
576 inflate_threshold_use = inflate_threshold_root;
578 inflate_threshold_use = inflate_threshold;
582 while ((tn->full_children > 0 && max_resize-- &&
583 50 * (tn->full_children + tnode_child_length(tn)
584 - tn->empty_children)
585 >= inflate_threshold_use * tnode_child_length(tn))) {
592 #ifdef CONFIG_IP_FIB_TRIE_STATS
593 t->stats.resize_node_skipped++;
599 if (max_resize < 0) {
601 pr_warning("Fix inflate_threshold_root."
602 " Now=%d size=%d bits\n",
603 inflate_threshold_root, tn->bits);
605 pr_warning("Fix inflate_threshold."
606 " Now=%d size=%d bits\n",
607 inflate_threshold, tn->bits);
613 * Halve as long as the number of empty children in this
614 * node is above threshold.
618 /* Keep root node larger */
621 halve_threshold_use = halve_threshold_root;
623 halve_threshold_use = halve_threshold;
627 while (tn->bits > 1 && max_resize-- &&
628 100 * (tnode_child_length(tn) - tn->empty_children) <
629 halve_threshold_use * tnode_child_length(tn)) {
635 #ifdef CONFIG_IP_FIB_TRIE_STATS
636 t->stats.resize_node_skipped++;
642 if (max_resize < 0) {
644 pr_warning("Fix halve_threshold_root."
645 " Now=%d size=%d bits\n",
646 halve_threshold_root, tn->bits);
648 pr_warning("Fix halve_threshold."
649 " Now=%d size=%d bits\n",
650 halve_threshold, tn->bits);
653 /* Only one child remains */
654 if (tn->empty_children == tnode_child_length(tn) - 1)
655 for (i = 0; i < tnode_child_length(tn); i++) {
662 /* compress one level */
664 node_set_parent(n, NULL);
669 return (struct node *) tn;
672 static struct tnode *inflate(struct trie *t, struct tnode *tn)
674 struct tnode *oldtnode = tn;
675 int olen = tnode_child_length(tn);
678 pr_debug("In inflate\n");
680 tn = tnode_new(oldtnode->key, oldtnode->pos, oldtnode->bits + 1);
683 return ERR_PTR(-ENOMEM);
686 * Preallocate and store tnodes before the actual work so we
687 * don't get into an inconsistent state if memory allocation
688 * fails. In case of failure we return the oldnode and inflate
689 * of tnode is ignored.
692 for (i = 0; i < olen; i++) {
695 inode = (struct tnode *) tnode_get_child(oldtnode, i);
698 inode->pos == oldtnode->pos + oldtnode->bits &&
700 struct tnode *left, *right;
701 t_key m = ~0U << (KEYLENGTH - 1) >> inode->pos;
703 left = tnode_new(inode->key&(~m), inode->pos + 1,
708 right = tnode_new(inode->key|m, inode->pos + 1,
716 put_child(t, tn, 2*i, (struct node *) left);
717 put_child(t, tn, 2*i+1, (struct node *) right);
721 for (i = 0; i < olen; i++) {
723 struct node *node = tnode_get_child(oldtnode, i);
724 struct tnode *left, *right;
731 /* A leaf or an internal node with skipped bits */
733 if (IS_LEAF(node) || ((struct tnode *) node)->pos >
734 tn->pos + tn->bits - 1) {
735 if (tkey_extract_bits(node->key,
736 oldtnode->pos + oldtnode->bits,
738 put_child(t, tn, 2*i, node);
740 put_child(t, tn, 2*i+1, node);
744 /* An internal node with two children */
745 inode = (struct tnode *) node;
747 if (inode->bits == 1) {
748 put_child(t, tn, 2*i, inode->child[0]);
749 put_child(t, tn, 2*i+1, inode->child[1]);
755 /* An internal node with more than two children */
757 /* We will replace this node 'inode' with two new
758 * ones, 'left' and 'right', each with half of the
759 * original children. The two new nodes will have
760 * a position one bit further down the key and this
761 * means that the "significant" part of their keys
762 * (see the discussion near the top of this file)
763 * will differ by one bit, which will be "0" in
764 * left's key and "1" in right's key. Since we are
765 * moving the key position by one step, the bit that
766 * we are moving away from - the bit at position
767 * (inode->pos) - is the one that will differ between
768 * left and right. So... we synthesize that bit in the
770 * The mask 'm' below will be a single "one" bit at
771 * the position (inode->pos)
774 /* Use the old key, but set the new significant
778 left = (struct tnode *) tnode_get_child(tn, 2*i);
779 put_child(t, tn, 2*i, NULL);
783 right = (struct tnode *) tnode_get_child(tn, 2*i+1);
784 put_child(t, tn, 2*i+1, NULL);
788 size = tnode_child_length(left);
789 for (j = 0; j < size; j++) {
790 put_child(t, left, j, inode->child[j]);
791 put_child(t, right, j, inode->child[j + size]);
793 put_child(t, tn, 2*i, resize(t, left));
794 put_child(t, tn, 2*i+1, resize(t, right));
798 tnode_free(oldtnode);
802 int size = tnode_child_length(tn);
805 for (j = 0; j < size; j++)
807 tnode_free((struct tnode *)tn->child[j]);
811 return ERR_PTR(-ENOMEM);
815 static struct tnode *halve(struct trie *t, struct tnode *tn)
817 struct tnode *oldtnode = tn;
818 struct node *left, *right;
820 int olen = tnode_child_length(tn);
822 pr_debug("In halve\n");
824 tn = tnode_new(oldtnode->key, oldtnode->pos, oldtnode->bits - 1);
827 return ERR_PTR(-ENOMEM);
830 * Preallocate and store tnodes before the actual work so we
831 * don't get into an inconsistent state if memory allocation
832 * fails. In case of failure we return the oldnode and halve
833 * of tnode is ignored.
836 for (i = 0; i < olen; i += 2) {
837 left = tnode_get_child(oldtnode, i);
838 right = tnode_get_child(oldtnode, i+1);
840 /* Two nonempty children */
844 newn = tnode_new(left->key, tn->pos + tn->bits, 1);
849 put_child(t, tn, i/2, (struct node *)newn);
854 for (i = 0; i < olen; i += 2) {
855 struct tnode *newBinNode;
857 left = tnode_get_child(oldtnode, i);
858 right = tnode_get_child(oldtnode, i+1);
860 /* At least one of the children is empty */
862 if (right == NULL) /* Both are empty */
864 put_child(t, tn, i/2, right);
869 put_child(t, tn, i/2, left);
873 /* Two nonempty children */
874 newBinNode = (struct tnode *) tnode_get_child(tn, i/2);
875 put_child(t, tn, i/2, NULL);
876 put_child(t, newBinNode, 0, left);
877 put_child(t, newBinNode, 1, right);
878 put_child(t, tn, i/2, resize(t, newBinNode));
880 tnode_free(oldtnode);
884 int size = tnode_child_length(tn);
887 for (j = 0; j < size; j++)
889 tnode_free((struct tnode *)tn->child[j]);
893 return ERR_PTR(-ENOMEM);
897 /* readside must use rcu_read_lock currently dump routines
898 via get_fa_head and dump */
900 static struct leaf_info *find_leaf_info(struct leaf *l, int plen)
902 struct hlist_head *head = &l->list;
903 struct hlist_node *node;
904 struct leaf_info *li;
906 hlist_for_each_entry_rcu(li, node, head, hlist)
907 if (li->plen == plen)
913 static inline struct list_head *get_fa_head(struct leaf *l, int plen)
915 struct leaf_info *li = find_leaf_info(l, plen);
923 static void insert_leaf_info(struct hlist_head *head, struct leaf_info *new)
925 struct leaf_info *li = NULL, *last = NULL;
926 struct hlist_node *node;
928 if (hlist_empty(head)) {
929 hlist_add_head_rcu(&new->hlist, head);
931 hlist_for_each_entry(li, node, head, hlist) {
932 if (new->plen > li->plen)
938 hlist_add_after_rcu(&last->hlist, &new->hlist);
940 hlist_add_before_rcu(&new->hlist, &li->hlist);
944 /* rcu_read_lock needs to be hold by caller from readside */
947 fib_find_node(struct trie *t, u32 key)
954 n = rcu_dereference(t->trie);
956 while (n != NULL && NODE_TYPE(n) == T_TNODE) {
957 tn = (struct tnode *) n;
961 if (tkey_sub_equals(tn->key, pos, tn->pos-pos, key)) {
962 pos = tn->pos + tn->bits;
963 n = tnode_get_child_rcu(tn,
964 tkey_extract_bits(key,
970 /* Case we have found a leaf. Compare prefixes */
972 if (n != NULL && IS_LEAF(n) && tkey_equals(key, n->key))
973 return (struct leaf *)n;
978 static struct node *trie_rebalance(struct trie *t, struct tnode *tn)
981 t_key cindex, key = tn->key;
984 while (tn != NULL && (tp = node_parent((struct node *)tn)) != NULL) {
985 cindex = tkey_extract_bits(key, tp->pos, tp->bits);
986 wasfull = tnode_full(tp, tnode_get_child(tp, cindex));
987 tn = (struct tnode *) resize(t, (struct tnode *)tn);
989 tnode_put_child_reorg((struct tnode *)tp, cindex,
990 (struct node *)tn, wasfull);
992 tp = node_parent((struct node *) tn);
998 /* Handle last (top) tnode */
1000 tn = (struct tnode *)resize(t, (struct tnode *)tn);
1002 return (struct node *)tn;
1005 /* only used from updater-side */
1007 static struct list_head *fib_insert_node(struct trie *t, u32 key, int plen)
1010 struct tnode *tp = NULL, *tn = NULL;
1014 struct list_head *fa_head = NULL;
1015 struct leaf_info *li;
1021 /* If we point to NULL, stop. Either the tree is empty and we should
1022 * just put a new leaf in if, or we have reached an empty child slot,
1023 * and we should just put our new leaf in that.
1024 * If we point to a T_TNODE, check if it matches our key. Note that
1025 * a T_TNODE might be skipping any number of bits - its 'pos' need
1026 * not be the parent's 'pos'+'bits'!
1028 * If it does match the current key, get pos/bits from it, extract
1029 * the index from our key, push the T_TNODE and walk the tree.
1031 * If it doesn't, we have to replace it with a new T_TNODE.
1033 * If we point to a T_LEAF, it might or might not have the same key
1034 * as we do. If it does, just change the value, update the T_LEAF's
1035 * value, and return it.
1036 * If it doesn't, we need to replace it with a T_TNODE.
1039 while (n != NULL && NODE_TYPE(n) == T_TNODE) {
1040 tn = (struct tnode *) n;
1044 if (tkey_sub_equals(tn->key, pos, tn->pos-pos, key)) {
1046 pos = tn->pos + tn->bits;
1047 n = tnode_get_child(tn,
1048 tkey_extract_bits(key,
1052 BUG_ON(n && node_parent(n) != tn);
1058 * n ----> NULL, LEAF or TNODE
1060 * tp is n's (parent) ----> NULL or TNODE
1063 BUG_ON(tp && IS_LEAF(tp));
1065 /* Case 1: n is a leaf. Compare prefixes */
1067 if (n != NULL && IS_LEAF(n) && tkey_equals(key, n->key)) {
1068 l = (struct leaf *) n;
1069 li = leaf_info_new(plen);
1074 fa_head = &li->falh;
1075 insert_leaf_info(&l->list, li);
1084 li = leaf_info_new(plen);
1087 tnode_free((struct tnode *) l);
1091 fa_head = &li->falh;
1092 insert_leaf_info(&l->list, li);
1094 if (t->trie && n == NULL) {
1095 /* Case 2: n is NULL, and will just insert a new leaf */
1097 node_set_parent((struct node *)l, tp);
1099 cindex = tkey_extract_bits(key, tp->pos, tp->bits);
1100 put_child(t, (struct tnode *)tp, cindex, (struct node *)l);
1102 /* Case 3: n is a LEAF or a TNODE and the key doesn't match. */
1104 * Add a new tnode here
1105 * first tnode need some special handling
1109 pos = tp->pos+tp->bits;
1114 newpos = tkey_mismatch(key, pos, n->key);
1115 tn = tnode_new(n->key, newpos, 1);
1118 tn = tnode_new(key, newpos, 1); /* First tnode */
1123 tnode_free((struct tnode *) l);
1127 node_set_parent((struct node *)tn, tp);
1129 missbit = tkey_extract_bits(key, newpos, 1);
1130 put_child(t, tn, missbit, (struct node *)l);
1131 put_child(t, tn, 1-missbit, n);
1134 cindex = tkey_extract_bits(key, tp->pos, tp->bits);
1135 put_child(t, (struct tnode *)tp, cindex,
1138 rcu_assign_pointer(t->trie, (struct node *)tn);
1143 if (tp && tp->pos + tp->bits > 32)
1144 pr_warning("fib_trie"
1145 " tp=%p pos=%d, bits=%d, key=%0x plen=%d\n",
1146 tp, tp->pos, tp->bits, key, plen);
1148 /* Rebalance the trie */
1150 rcu_assign_pointer(t->trie, trie_rebalance(t, tp));
1156 * Caller must hold RTNL.
1158 static int fn_trie_insert(struct fib_table *tb, struct fib_config *cfg)
1160 struct trie *t = (struct trie *) tb->tb_data;
1161 struct fib_alias *fa, *new_fa;
1162 struct list_head *fa_head = NULL;
1163 struct fib_info *fi;
1164 int plen = cfg->fc_dst_len;
1165 u8 tos = cfg->fc_tos;
1173 key = ntohl(cfg->fc_dst);
1175 pr_debug("Insert table=%u %08x/%d\n", tb->tb_id, key, plen);
1177 mask = ntohl(inet_make_mask(plen));
1184 fi = fib_create_info(cfg);
1190 l = fib_find_node(t, key);
1194 fa_head = get_fa_head(l, plen);
1195 fa = fib_find_alias(fa_head, tos, fi->fib_priority);
1198 /* Now fa, if non-NULL, points to the first fib alias
1199 * with the same keys [prefix,tos,priority], if such key already
1200 * exists or to the node before which we will insert new one.
1202 * If fa is NULL, we will need to allocate a new one and
1203 * insert to the head of f.
1205 * If f is NULL, no fib node matched the destination key
1206 * and we need to allocate a new one of those as well.
1209 if (fa && fa->fa_info->fib_priority == fi->fib_priority) {
1210 struct fib_alias *fa_orig;
1213 if (cfg->fc_nlflags & NLM_F_EXCL)
1216 if (cfg->fc_nlflags & NLM_F_REPLACE) {
1217 struct fib_info *fi_drop;
1220 if (fi->fib_treeref > 1)
1224 new_fa = kmem_cache_alloc(fn_alias_kmem, GFP_KERNEL);
1228 fi_drop = fa->fa_info;
1229 new_fa->fa_tos = fa->fa_tos;
1230 new_fa->fa_info = fi;
1231 new_fa->fa_type = cfg->fc_type;
1232 new_fa->fa_scope = cfg->fc_scope;
1233 state = fa->fa_state;
1234 new_fa->fa_state &= ~FA_S_ACCESSED;
1236 list_replace_rcu(&fa->fa_list, &new_fa->fa_list);
1237 alias_free_mem_rcu(fa);
1239 fib_release_info(fi_drop);
1240 if (state & FA_S_ACCESSED)
1242 rtmsg_fib(RTM_NEWROUTE, htonl(key), new_fa, plen,
1243 tb->tb_id, &cfg->fc_nlinfo, NLM_F_REPLACE);
1247 /* Error if we find a perfect match which
1248 * uses the same scope, type, and nexthop
1252 list_for_each_entry(fa, fa_orig->fa_list.prev, fa_list) {
1253 if (fa->fa_tos != tos)
1255 if (fa->fa_info->fib_priority != fi->fib_priority)
1257 if (fa->fa_type == cfg->fc_type &&
1258 fa->fa_scope == cfg->fc_scope &&
1263 if (!(cfg->fc_nlflags & NLM_F_APPEND))
1267 if (!(cfg->fc_nlflags & NLM_F_CREATE))
1271 new_fa = kmem_cache_alloc(fn_alias_kmem, GFP_KERNEL);
1275 new_fa->fa_info = fi;
1276 new_fa->fa_tos = tos;
1277 new_fa->fa_type = cfg->fc_type;
1278 new_fa->fa_scope = cfg->fc_scope;
1279 new_fa->fa_state = 0;
1281 * Insert new entry to the list.
1285 fa_head = fib_insert_node(t, key, plen);
1286 if (unlikely(!fa_head)) {
1288 goto out_free_new_fa;
1292 list_add_tail_rcu(&new_fa->fa_list,
1293 (fa ? &fa->fa_list : fa_head));
1296 rtmsg_fib(RTM_NEWROUTE, htonl(key), new_fa, plen, tb->tb_id,
1297 &cfg->fc_nlinfo, 0);
1302 kmem_cache_free(fn_alias_kmem, new_fa);
1304 fib_release_info(fi);
1310 /* should be called with rcu_read_lock */
1311 static int check_leaf(struct trie *t, struct leaf *l,
1312 t_key key, const struct flowi *flp,
1313 struct fib_result *res)
1315 struct leaf_info *li;
1316 struct hlist_head *hhead = &l->list;
1317 struct hlist_node *node;
1319 hlist_for_each_entry_rcu(li, node, hhead, hlist) {
1321 int plen = li->plen;
1322 __be32 mask = inet_make_mask(plen);
1324 if (l->key != (key & ntohl(mask)))
1327 err = fib_semantic_match(&li->falh, flp, res,
1328 htonl(l->key), mask, plen);
1330 #ifdef CONFIG_IP_FIB_TRIE_STATS
1332 t->stats.semantic_match_passed++;
1334 t->stats.semantic_match_miss++;
1343 static int fn_trie_lookup(struct fib_table *tb, const struct flowi *flp,
1344 struct fib_result *res)
1346 struct trie *t = (struct trie *) tb->tb_data;
1351 t_key key = ntohl(flp->fl4_dst);
1354 int current_prefix_length = KEYLENGTH;
1356 t_key node_prefix, key_prefix, pref_mismatch;
1361 n = rcu_dereference(t->trie);
1365 #ifdef CONFIG_IP_FIB_TRIE_STATS
1371 plen = check_leaf(t, (struct leaf *)n, key, flp, res);
1378 pn = (struct tnode *) n;
1386 cindex = tkey_extract_bits(mask_pfx(key, current_prefix_length),
1389 n = tnode_get_child(pn, cindex);
1392 #ifdef CONFIG_IP_FIB_TRIE_STATS
1393 t->stats.null_node_hit++;
1399 plen = check_leaf(t, (struct leaf *)n, key, flp, res);
1407 cn = (struct tnode *)n;
1410 * It's a tnode, and we can do some extra checks here if we
1411 * like, to avoid descending into a dead-end branch.
1412 * This tnode is in the parent's child array at index
1413 * key[p_pos..p_pos+p_bits] but potentially with some bits
1414 * chopped off, so in reality the index may be just a
1415 * subprefix, padded with zero at the end.
1416 * We can also take a look at any skipped bits in this
1417 * tnode - everything up to p_pos is supposed to be ok,
1418 * and the non-chopped bits of the index (se previous
1419 * paragraph) are also guaranteed ok, but the rest is
1420 * considered unknown.
1422 * The skipped bits are key[pos+bits..cn->pos].
1425 /* If current_prefix_length < pos+bits, we are already doing
1426 * actual prefix matching, which means everything from
1427 * pos+(bits-chopped_off) onward must be zero along some
1428 * branch of this subtree - otherwise there is *no* valid
1429 * prefix present. Here we can only check the skipped
1430 * bits. Remember, since we have already indexed into the
1431 * parent's child array, we know that the bits we chopped of
1435 /* NOTA BENE: Checking only skipped bits
1436 for the new node here */
1438 if (current_prefix_length < pos+bits) {
1439 if (tkey_extract_bits(cn->key, current_prefix_length,
1440 cn->pos - current_prefix_length)
1446 * If chopped_off=0, the index is fully validated and we
1447 * only need to look at the skipped bits for this, the new,
1448 * tnode. What we actually want to do is to find out if
1449 * these skipped bits match our key perfectly, or if we will
1450 * have to count on finding a matching prefix further down,
1451 * because if we do, we would like to have some way of
1452 * verifying the existence of such a prefix at this point.
1455 /* The only thing we can do at this point is to verify that
1456 * any such matching prefix can indeed be a prefix to our
1457 * key, and if the bits in the node we are inspecting that
1458 * do not match our key are not ZERO, this cannot be true.
1459 * Thus, find out where there is a mismatch (before cn->pos)
1460 * and verify that all the mismatching bits are zero in the
1465 * Note: We aren't very concerned about the piece of
1466 * the key that precede pn->pos+pn->bits, since these
1467 * have already been checked. The bits after cn->pos
1468 * aren't checked since these are by definition
1469 * "unknown" at this point. Thus, what we want to see
1470 * is if we are about to enter the "prefix matching"
1471 * state, and in that case verify that the skipped
1472 * bits that will prevail throughout this subtree are
1473 * zero, as they have to be if we are to find a
1477 node_prefix = mask_pfx(cn->key, cn->pos);
1478 key_prefix = mask_pfx(key, cn->pos);
1479 pref_mismatch = key_prefix^node_prefix;
1483 * In short: If skipped bits in this node do not match
1484 * the search key, enter the "prefix matching"
1487 if (pref_mismatch) {
1488 while (!(pref_mismatch & (1<<(KEYLENGTH-1)))) {
1490 pref_mismatch = pref_mismatch << 1;
1492 key_prefix = tkey_extract_bits(cn->key, mp, cn->pos-mp);
1494 if (key_prefix != 0)
1497 if (current_prefix_length >= cn->pos)
1498 current_prefix_length = mp;
1501 pn = (struct tnode *)n; /* Descend */
1508 /* As zero don't change the child key (cindex) */
1509 while ((chopped_off <= pn->bits)
1510 && !(cindex & (1<<(chopped_off-1))))
1513 /* Decrease current_... with bits chopped off */
1514 if (current_prefix_length > pn->pos + pn->bits - chopped_off)
1515 current_prefix_length = pn->pos + pn->bits
1519 * Either we do the actual chop off according or if we have
1520 * chopped off all bits in this tnode walk up to our parent.
1523 if (chopped_off <= pn->bits) {
1524 cindex &= ~(1 << (chopped_off-1));
1526 struct tnode *parent = node_parent((struct node *) pn);
1530 /* Get Child's index */
1531 cindex = tkey_extract_bits(pn->key, parent->pos, parent->bits);
1535 #ifdef CONFIG_IP_FIB_TRIE_STATS
1536 t->stats.backtrack++;
1548 /* only called from updater side */
1549 static int trie_leaf_remove(struct trie *t, t_key key)
1552 struct tnode *tp = NULL;
1553 struct node *n = t->trie;
1556 pr_debug("entering trie_leaf_remove(%p)\n", n);
1558 /* Note that in the case skipped bits, those bits are *not* checked!
1559 * When we finish this, we will have NULL or a T_LEAF, and the
1560 * T_LEAF may or may not match our key.
1563 while (n != NULL && IS_TNODE(n)) {
1564 struct tnode *tn = (struct tnode *) n;
1566 n = tnode_get_child(tn, tkey_extract_bits(key,
1567 tn->pos, tn->bits));
1569 BUG_ON(n && node_parent(n) != tn);
1571 l = (struct leaf *) n;
1573 if (!n || !tkey_equals(l->key, key))
1578 * Remove the leaf and rebalance the tree
1580 tp = node_parent(n);
1581 tnode_free((struct tnode *) n);
1584 cindex = tkey_extract_bits(key, tp->pos, tp->bits);
1585 put_child(t, (struct tnode *)tp, cindex, NULL);
1586 rcu_assign_pointer(t->trie, trie_rebalance(t, tp));
1588 rcu_assign_pointer(t->trie, NULL);
1594 * Caller must hold RTNL.
1596 static int fn_trie_delete(struct fib_table *tb, struct fib_config *cfg)
1598 struct trie *t = (struct trie *) tb->tb_data;
1600 int plen = cfg->fc_dst_len;
1601 u8 tos = cfg->fc_tos;
1602 struct fib_alias *fa, *fa_to_delete;
1603 struct list_head *fa_head;
1605 struct leaf_info *li;
1610 key = ntohl(cfg->fc_dst);
1611 mask = ntohl(inet_make_mask(plen));
1617 l = fib_find_node(t, key);
1622 fa_head = get_fa_head(l, plen);
1623 fa = fib_find_alias(fa_head, tos, 0);
1628 pr_debug("Deleting %08x/%d tos=%d t=%p\n", key, plen, tos, t);
1630 fa_to_delete = NULL;
1631 fa_head = fa->fa_list.prev;
1633 list_for_each_entry(fa, fa_head, fa_list) {
1634 struct fib_info *fi = fa->fa_info;
1636 if (fa->fa_tos != tos)
1639 if ((!cfg->fc_type || fa->fa_type == cfg->fc_type) &&
1640 (cfg->fc_scope == RT_SCOPE_NOWHERE ||
1641 fa->fa_scope == cfg->fc_scope) &&
1642 (!cfg->fc_protocol ||
1643 fi->fib_protocol == cfg->fc_protocol) &&
1644 fib_nh_match(cfg, fi) == 0) {
1654 rtmsg_fib(RTM_DELROUTE, htonl(key), fa, plen, tb->tb_id,
1655 &cfg->fc_nlinfo, 0);
1657 l = fib_find_node(t, key);
1658 li = find_leaf_info(l, plen);
1660 list_del_rcu(&fa->fa_list);
1662 if (list_empty(fa_head)) {
1663 hlist_del_rcu(&li->hlist);
1667 if (hlist_empty(&l->list))
1668 trie_leaf_remove(t, key);
1670 if (fa->fa_state & FA_S_ACCESSED)
1673 fib_release_info(fa->fa_info);
1674 alias_free_mem_rcu(fa);
1678 static int trie_flush_list(struct trie *t, struct list_head *head)
1680 struct fib_alias *fa, *fa_node;
1683 list_for_each_entry_safe(fa, fa_node, head, fa_list) {
1684 struct fib_info *fi = fa->fa_info;
1686 if (fi && (fi->fib_flags & RTNH_F_DEAD)) {
1687 list_del_rcu(&fa->fa_list);
1688 fib_release_info(fa->fa_info);
1689 alias_free_mem_rcu(fa);
1696 static int trie_flush_leaf(struct trie *t, struct leaf *l)
1699 struct hlist_head *lih = &l->list;
1700 struct hlist_node *node, *tmp;
1701 struct leaf_info *li = NULL;
1703 hlist_for_each_entry_safe(li, node, tmp, lih, hlist) {
1704 found += trie_flush_list(t, &li->falh);
1706 if (list_empty(&li->falh)) {
1707 hlist_del_rcu(&li->hlist);
1714 /* rcu_read_lock needs to be hold by caller from readside */
1716 static struct leaf *nextleaf(struct trie *t, struct leaf *thisleaf)
1718 struct node *c = (struct node *) thisleaf;
1721 struct node *trie = rcu_dereference(t->trie);
1727 if (IS_LEAF(trie)) /* trie w. just a leaf */
1728 return (struct leaf *) trie;
1730 p = (struct tnode *)trie; /* Start */
1732 p = node_parent_rcu(c);
1737 /* Find the next child of the parent */
1739 pos = 1 + tkey_extract_bits(c->key, p->pos, p->bits);
1743 last = 1 << p->bits;
1744 for (idx = pos; idx < last ; idx++) {
1745 c = rcu_dereference(p->child[idx]);
1750 /* Decend if tnode */
1751 while (IS_TNODE(c)) {
1752 p = (struct tnode *) c;
1755 /* Rightmost non-NULL branch */
1756 if (p && IS_TNODE(p))
1757 while (!(c = rcu_dereference(p->child[idx]))
1758 && idx < (1<<p->bits)) idx++;
1760 /* Done with this tnode? */
1761 if (idx >= (1 << p->bits) || !c)
1764 return (struct leaf *) c;
1767 /* No more children go up one step */
1768 c = (struct node *) p;
1769 p = node_parent_rcu(c);
1771 return NULL; /* Ready. Root of trie */
1775 * Caller must hold RTNL.
1777 static int fn_trie_flush(struct fib_table *tb)
1779 struct trie *t = (struct trie *) tb->tb_data;
1780 struct leaf *ll = NULL, *l = NULL;
1783 for (h = 0; (l = nextleaf(t, l)) != NULL; h++) {
1784 found += trie_flush_leaf(t, l);
1786 if (ll && hlist_empty(&ll->list))
1787 trie_leaf_remove(t, ll->key);
1791 if (ll && hlist_empty(&ll->list))
1792 trie_leaf_remove(t, ll->key);
1794 pr_debug("trie_flush found=%d\n", found);
1798 static void fn_trie_select_default(struct fib_table *tb,
1799 const struct flowi *flp,
1800 struct fib_result *res)
1802 struct trie *t = (struct trie *) tb->tb_data;
1803 int order, last_idx;
1804 struct fib_info *fi = NULL;
1805 struct fib_info *last_resort;
1806 struct fib_alias *fa = NULL;
1807 struct list_head *fa_head;
1816 l = fib_find_node(t, 0);
1820 fa_head = get_fa_head(l, 0);
1824 if (list_empty(fa_head))
1827 list_for_each_entry_rcu(fa, fa_head, fa_list) {
1828 struct fib_info *next_fi = fa->fa_info;
1830 if (fa->fa_scope != res->scope ||
1831 fa->fa_type != RTN_UNICAST)
1834 if (next_fi->fib_priority > res->fi->fib_priority)
1836 if (!next_fi->fib_nh[0].nh_gw ||
1837 next_fi->fib_nh[0].nh_scope != RT_SCOPE_LINK)
1839 fa->fa_state |= FA_S_ACCESSED;
1842 if (next_fi != res->fi)
1844 } else if (!fib_detect_death(fi, order, &last_resort,
1845 &last_idx, tb->tb_default)) {
1846 fib_result_assign(res, fi);
1847 tb->tb_default = order;
1853 if (order <= 0 || fi == NULL) {
1854 tb->tb_default = -1;
1858 if (!fib_detect_death(fi, order, &last_resort, &last_idx,
1860 fib_result_assign(res, fi);
1861 tb->tb_default = order;
1865 fib_result_assign(res, last_resort);
1866 tb->tb_default = last_idx;
1871 static int fn_trie_dump_fa(t_key key, int plen, struct list_head *fah,
1872 struct fib_table *tb,
1873 struct sk_buff *skb, struct netlink_callback *cb)
1876 struct fib_alias *fa;
1878 __be32 xkey = htonl(key);
1883 /* rcu_read_lock is hold by caller */
1885 list_for_each_entry_rcu(fa, fah, fa_list) {
1890 BUG_ON(!fa->fa_info);
1892 if (fib_dump_info(skb, NETLINK_CB(cb->skb).pid,
1901 fa->fa_info, 0) < 0) {
1911 static int fn_trie_dump_plen(struct trie *t, int plen, struct fib_table *tb,
1912 struct sk_buff *skb, struct netlink_callback *cb)
1915 struct list_head *fa_head;
1916 struct leaf *l = NULL;
1920 for (h = 0; (l = nextleaf(t, l)) != NULL; h++) {
1924 memset(&cb->args[4], 0,
1925 sizeof(cb->args) - 4*sizeof(cb->args[0]));
1927 fa_head = get_fa_head(l, plen);
1932 if (list_empty(fa_head))
1935 if (fn_trie_dump_fa(l->key, plen, fa_head, tb, skb, cb) < 0) {
1944 static int fn_trie_dump(struct fib_table *tb, struct sk_buff *skb,
1945 struct netlink_callback *cb)
1948 struct trie *t = (struct trie *) tb->tb_data;
1953 for (m = 0; m <= 32; m++) {
1957 memset(&cb->args[3], 0,
1958 sizeof(cb->args) - 3*sizeof(cb->args[0]));
1960 if (fn_trie_dump_plen(t, 32-m, tb, skb, cb) < 0) {
1973 void __init fib_hash_init(void)
1975 fn_alias_kmem = kmem_cache_create("ip_fib_alias",
1976 sizeof(struct fib_alias),
1977 0, SLAB_PANIC, NULL);
1979 trie_leaf_kmem = kmem_cache_create("ip_fib_trie",
1980 max(sizeof(struct leaf),
1981 sizeof(struct leaf_info)),
1982 0, SLAB_PANIC, NULL);
1986 /* Fix more generic FIB names for init later */
1987 struct fib_table *fib_hash_table(u32 id)
1989 struct fib_table *tb;
1992 tb = kmalloc(sizeof(struct fib_table) + sizeof(struct trie),
1998 tb->tb_default = -1;
1999 tb->tb_lookup = fn_trie_lookup;
2000 tb->tb_insert = fn_trie_insert;
2001 tb->tb_delete = fn_trie_delete;
2002 tb->tb_flush = fn_trie_flush;
2003 tb->tb_select_default = fn_trie_select_default;
2004 tb->tb_dump = fn_trie_dump;
2006 t = (struct trie *) tb->tb_data;
2007 memset(t, 0, sizeof(*t));
2009 if (id == RT_TABLE_LOCAL)
2010 pr_info("IPv4 FIB: Using LC-trie version %s\n", VERSION);
2015 #ifdef CONFIG_PROC_FS
2016 /* Depth first Trie walk iterator */
2017 struct fib_trie_iter {
2018 struct seq_net_private p;
2019 struct trie *trie_local, *trie_main;
2020 struct tnode *tnode;
2026 static struct node *fib_trie_get_next(struct fib_trie_iter *iter)
2028 struct tnode *tn = iter->tnode;
2029 unsigned cindex = iter->index;
2032 /* A single entry routing table */
2036 pr_debug("get_next iter={node=%p index=%d depth=%d}\n",
2037 iter->tnode, iter->index, iter->depth);
2039 while (cindex < (1<<tn->bits)) {
2040 struct node *n = tnode_get_child_rcu(tn, cindex);
2045 iter->index = cindex + 1;
2047 /* push down one level */
2048 iter->tnode = (struct tnode *) n;
2058 /* Current node exhausted, pop back up */
2059 p = node_parent_rcu((struct node *)tn);
2061 cindex = tkey_extract_bits(tn->key, p->pos, p->bits)+1;
2071 static struct node *fib_trie_get_first(struct fib_trie_iter *iter,
2079 n = rcu_dereference(t->trie);
2086 iter->tnode = (struct tnode *) n;
2101 static void trie_collect_stats(struct trie *t, struct trie_stat *s)
2104 struct fib_trie_iter iter;
2106 memset(s, 0, sizeof(*s));
2109 for (n = fib_trie_get_first(&iter, t); n;
2110 n = fib_trie_get_next(&iter)) {
2112 struct leaf *l = (struct leaf *)n;
2113 struct leaf_info *li;
2114 struct hlist_node *tmp;
2117 s->totdepth += iter.depth;
2118 if (iter.depth > s->maxdepth)
2119 s->maxdepth = iter.depth;
2121 hlist_for_each_entry_rcu(li, tmp, &l->list, hlist)
2124 const struct tnode *tn = (const struct tnode *) n;
2128 if (tn->bits < MAX_STAT_DEPTH)
2129 s->nodesizes[tn->bits]++;
2131 for (i = 0; i < (1<<tn->bits); i++)
2140 * This outputs /proc/net/fib_triestats
2142 static void trie_show_stats(struct seq_file *seq, struct trie_stat *stat)
2144 unsigned i, max, pointers, bytes, avdepth;
2147 avdepth = stat->totdepth*100 / stat->leaves;
2151 seq_printf(seq, "\tAver depth: %u.%02d\n",
2152 avdepth / 100, avdepth % 100);
2153 seq_printf(seq, "\tMax depth: %u\n", stat->maxdepth);
2155 seq_printf(seq, "\tLeaves: %u\n", stat->leaves);
2156 bytes = sizeof(struct leaf) * stat->leaves;
2158 seq_printf(seq, "\tPrefixes: %u\n", stat->prefixes);
2159 bytes += sizeof(struct leaf_info) * stat->prefixes;
2161 seq_printf(seq, "\tInternal nodes: %u\n\t", stat->tnodes);
2162 bytes += sizeof(struct tnode) * stat->tnodes;
2164 max = MAX_STAT_DEPTH;
2165 while (max > 0 && stat->nodesizes[max-1] == 0)
2169 for (i = 1; i <= max; i++)
2170 if (stat->nodesizes[i] != 0) {
2171 seq_printf(seq, " %u: %u", i, stat->nodesizes[i]);
2172 pointers += (1<<i) * stat->nodesizes[i];
2174 seq_putc(seq, '\n');
2175 seq_printf(seq, "\tPointers: %u\n", pointers);
2177 bytes += sizeof(struct node *) * pointers;
2178 seq_printf(seq, "Null ptrs: %u\n", stat->nullpointers);
2179 seq_printf(seq, "Total size: %u kB\n", (bytes + 1023) / 1024);
2182 #ifdef CONFIG_IP_FIB_TRIE_STATS
2183 static void trie_show_usage(struct seq_file *seq,
2184 const struct trie_use_stats *stats)
2186 seq_printf(seq, "\nCounters:\n---------\n");
2187 seq_printf(seq, "gets = %u\n", stats->gets);
2188 seq_printf(seq, "backtracks = %u\n", stats->backtrack);
2189 seq_printf(seq, "semantic match passed = %u\n",
2190 stats->semantic_match_passed);
2191 seq_printf(seq, "semantic match miss = %u\n",
2192 stats->semantic_match_miss);
2193 seq_printf(seq, "null node hit= %u\n", stats->null_node_hit);
2194 seq_printf(seq, "skipped node resize = %u\n\n",
2195 stats->resize_node_skipped);
2197 #endif /* CONFIG_IP_FIB_TRIE_STATS */
2199 static void fib_trie_show(struct seq_file *seq, const char *name,
2202 struct trie_stat stat;
2204 trie_collect_stats(trie, &stat);
2205 seq_printf(seq, "%s:\n", name);
2206 trie_show_stats(seq, &stat);
2207 #ifdef CONFIG_IP_FIB_TRIE_STATS
2208 trie_show_usage(seq, &trie->stats);
2212 static int fib_triestat_seq_show(struct seq_file *seq, void *v)
2214 struct net *net = (struct net *)seq->private;
2215 struct fib_table *tb;
2218 "Basic info: size of leaf:"
2219 " %Zd bytes, size of tnode: %Zd bytes.\n",
2220 sizeof(struct leaf), sizeof(struct tnode));
2222 tb = fib_get_table(net, RT_TABLE_LOCAL);
2224 fib_trie_show(seq, "Local", (struct trie *) tb->tb_data);
2226 tb = fib_get_table(net, RT_TABLE_MAIN);
2228 fib_trie_show(seq, "Main", (struct trie *) tb->tb_data);
2233 static int fib_triestat_seq_open(struct inode *inode, struct file *file)
2238 net = get_proc_net(inode);
2241 err = single_open(file, fib_triestat_seq_show, net);
2249 static int fib_triestat_seq_release(struct inode *ino, struct file *f)
2251 struct seq_file *seq = f->private_data;
2252 put_net(seq->private);
2253 return single_release(ino, f);
2256 static const struct file_operations fib_triestat_fops = {
2257 .owner = THIS_MODULE,
2258 .open = fib_triestat_seq_open,
2260 .llseek = seq_lseek,
2261 .release = fib_triestat_seq_release,
2264 static struct node *fib_trie_get_idx(struct fib_trie_iter *iter,
2270 for (n = fib_trie_get_first(iter, iter->trie_local);
2271 n; ++idx, n = fib_trie_get_next(iter)) {
2276 for (n = fib_trie_get_first(iter, iter->trie_main);
2277 n; ++idx, n = fib_trie_get_next(iter)) {
2284 static void *fib_trie_seq_start(struct seq_file *seq, loff_t *pos)
2287 struct fib_trie_iter *iter = seq->private;
2288 struct fib_table *tb;
2290 if (!iter->trie_local) {
2291 tb = fib_get_table(iter->p.net, RT_TABLE_LOCAL);
2293 iter->trie_local = (struct trie *) tb->tb_data;
2295 if (!iter->trie_main) {
2296 tb = fib_get_table(iter->p.net, RT_TABLE_MAIN);
2298 iter->trie_main = (struct trie *) tb->tb_data;
2302 return SEQ_START_TOKEN;
2303 return fib_trie_get_idx(iter, *pos - 1);
2306 static void *fib_trie_seq_next(struct seq_file *seq, void *v, loff_t *pos)
2308 struct fib_trie_iter *iter = seq->private;
2312 if (v == SEQ_START_TOKEN)
2313 return fib_trie_get_idx(iter, 0);
2315 v = fib_trie_get_next(iter);
2320 /* continue scan in next trie */
2321 if (iter->trie == iter->trie_local)
2322 return fib_trie_get_first(iter, iter->trie_main);
2327 static void fib_trie_seq_stop(struct seq_file *seq, void *v)
2333 static void seq_indent(struct seq_file *seq, int n)
2335 while (n-- > 0) seq_puts(seq, " ");
2338 static inline const char *rtn_scope(char *buf, size_t len, enum rt_scope_t s)
2341 case RT_SCOPE_UNIVERSE: return "universe";
2342 case RT_SCOPE_SITE: return "site";
2343 case RT_SCOPE_LINK: return "link";
2344 case RT_SCOPE_HOST: return "host";
2345 case RT_SCOPE_NOWHERE: return "nowhere";
2347 snprintf(buf, len, "scope=%d", s);
2352 static const char *rtn_type_names[__RTN_MAX] = {
2353 [RTN_UNSPEC] = "UNSPEC",
2354 [RTN_UNICAST] = "UNICAST",
2355 [RTN_LOCAL] = "LOCAL",
2356 [RTN_BROADCAST] = "BROADCAST",
2357 [RTN_ANYCAST] = "ANYCAST",
2358 [RTN_MULTICAST] = "MULTICAST",
2359 [RTN_BLACKHOLE] = "BLACKHOLE",
2360 [RTN_UNREACHABLE] = "UNREACHABLE",
2361 [RTN_PROHIBIT] = "PROHIBIT",
2362 [RTN_THROW] = "THROW",
2364 [RTN_XRESOLVE] = "XRESOLVE",
2367 static inline const char *rtn_type(char *buf, size_t len, unsigned t)
2369 if (t < __RTN_MAX && rtn_type_names[t])
2370 return rtn_type_names[t];
2371 snprintf(buf, len, "type %u", t);
2375 /* Pretty print the trie */
2376 static int fib_trie_seq_show(struct seq_file *seq, void *v)
2378 const struct fib_trie_iter *iter = seq->private;
2381 if (v == SEQ_START_TOKEN)
2384 if (!node_parent_rcu(n)) {
2385 if (iter->trie == iter->trie_local)
2386 seq_puts(seq, "<local>:\n");
2388 seq_puts(seq, "<main>:\n");
2392 struct tnode *tn = (struct tnode *) n;
2393 __be32 prf = htonl(mask_pfx(tn->key, tn->pos));
2395 seq_indent(seq, iter->depth-1);
2396 seq_printf(seq, " +-- %d.%d.%d.%d/%d %d %d %d\n",
2397 NIPQUAD(prf), tn->pos, tn->bits, tn->full_children,
2398 tn->empty_children);
2401 struct leaf *l = (struct leaf *) n;
2403 __be32 val = htonl(l->key);
2405 seq_indent(seq, iter->depth);
2406 seq_printf(seq, " |-- %d.%d.%d.%d\n", NIPQUAD(val));
2407 for (i = 32; i >= 0; i--) {
2408 struct leaf_info *li = find_leaf_info(l, i);
2411 struct fib_alias *fa;
2413 list_for_each_entry_rcu(fa, &li->falh, fa_list) {
2414 char buf1[32], buf2[32];
2416 seq_indent(seq, iter->depth+1);
2417 seq_printf(seq, " /%d %s %s", i,
2418 rtn_scope(buf1, sizeof(buf1),
2420 rtn_type(buf2, sizeof(buf2),
2423 seq_printf(seq, "tos =%d\n",
2425 seq_putc(seq, '\n');
2434 static const struct seq_operations fib_trie_seq_ops = {
2435 .start = fib_trie_seq_start,
2436 .next = fib_trie_seq_next,
2437 .stop = fib_trie_seq_stop,
2438 .show = fib_trie_seq_show,
2441 static int fib_trie_seq_open(struct inode *inode, struct file *file)
2443 return seq_open_net(inode, file, &fib_trie_seq_ops,
2444 sizeof(struct fib_trie_iter));
2447 static const struct file_operations fib_trie_fops = {
2448 .owner = THIS_MODULE,
2449 .open = fib_trie_seq_open,
2451 .llseek = seq_lseek,
2452 .release = seq_release_net,
2455 static unsigned fib_flag_trans(int type, __be32 mask, const struct fib_info *fi)
2457 static unsigned type2flags[RTN_MAX + 1] = {
2458 [7] = RTF_REJECT, [8] = RTF_REJECT,
2460 unsigned flags = type2flags[type];
2462 if (fi && fi->fib_nh->nh_gw)
2463 flags |= RTF_GATEWAY;
2464 if (mask == htonl(0xFFFFFFFF))
2471 * This outputs /proc/net/route.
2472 * The format of the file is not supposed to be changed
2473 * and needs to be same as fib_hash output to avoid breaking
2476 static int fib_route_seq_show(struct seq_file *seq, void *v)
2478 const struct fib_trie_iter *iter = seq->private;
2483 if (v == SEQ_START_TOKEN) {
2484 seq_printf(seq, "%-127s\n", "Iface\tDestination\tGateway "
2485 "\tFlags\tRefCnt\tUse\tMetric\tMask\t\tMTU"
2490 if (iter->trie == iter->trie_local)
2496 for (i = 32; i >= 0; i--) {
2497 struct leaf_info *li = find_leaf_info(l, i);
2498 struct fib_alias *fa;
2499 __be32 mask, prefix;
2504 mask = inet_make_mask(li->plen);
2505 prefix = htonl(l->key);
2507 list_for_each_entry_rcu(fa, &li->falh, fa_list) {
2508 const struct fib_info *fi = fa->fa_info;
2509 unsigned flags = fib_flag_trans(fa->fa_type, mask, fi);
2511 if (fa->fa_type == RTN_BROADCAST
2512 || fa->fa_type == RTN_MULTICAST)
2516 snprintf(bf, sizeof(bf),
2517 "%s\t%08X\t%08X\t%04X\t%d\t%u\t%d\t%08X\t%d\t%u\t%u",
2518 fi->fib_dev ? fi->fib_dev->name : "*",
2520 fi->fib_nh->nh_gw, flags, 0, 0,
2524 fi->fib_advmss + 40 : 0),
2528 snprintf(bf, sizeof(bf),
2529 "*\t%08X\t%08X\t%04X\t%d\t%u\t%d\t%08X\t%d\t%u\t%u",
2530 prefix, 0, flags, 0, 0, 0,
2533 seq_printf(seq, "%-127s\n", bf);
2540 static const struct seq_operations fib_route_seq_ops = {
2541 .start = fib_trie_seq_start,
2542 .next = fib_trie_seq_next,
2543 .stop = fib_trie_seq_stop,
2544 .show = fib_route_seq_show,
2547 static int fib_route_seq_open(struct inode *inode, struct file *file)
2549 return seq_open_net(inode, file, &fib_route_seq_ops,
2550 sizeof(struct fib_trie_iter));
2553 static const struct file_operations fib_route_fops = {
2554 .owner = THIS_MODULE,
2555 .open = fib_route_seq_open,
2557 .llseek = seq_lseek,
2558 .release = seq_release_net,
2561 int __net_init fib_proc_init(struct net *net)
2563 if (!proc_net_fops_create(net, "fib_trie", S_IRUGO, &fib_trie_fops))
2566 if (!proc_net_fops_create(net, "fib_triestat", S_IRUGO,
2567 &fib_triestat_fops))
2570 if (!proc_net_fops_create(net, "route", S_IRUGO, &fib_route_fops))
2576 proc_net_remove(net, "fib_triestat");
2578 proc_net_remove(net, "fib_trie");
2583 void __net_exit fib_proc_exit(struct net *net)
2585 proc_net_remove(net, "fib_trie");
2586 proc_net_remove(net, "fib_triestat");
2587 proc_net_remove(net, "route");
2590 #endif /* CONFIG_PROC_FS */