[ALSA] usb-audio - Fix double comment
[linux-2.6/sactl.git] / net / ipv4 / fib_trie.c
blob81a8285d6d6a4251c7cd166635f7058046078bf6
1 /*
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 <asm/bitops.h>
58 #include <linux/types.h>
59 #include <linux/kernel.h>
60 #include <linux/mm.h>
61 #include <linux/string.h>
62 #include <linux/socket.h>
63 #include <linux/sockios.h>
64 #include <linux/errno.h>
65 #include <linux/in.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>
77 #include <net/ip.h>
78 #include <net/protocol.h>
79 #include <net/route.h>
80 #include <net/tcp.h>
81 #include <net/sock.h>
82 #include <net/ip_fib.h>
83 #include "fib_lookup.h"
85 #undef CONFIG_IP_FIB_TRIE_STATS
86 #define MAX_STAT_DEPTH 32
88 #define KEYLENGTH (8*sizeof(t_key))
90 typedef unsigned int t_key;
92 #define T_TNODE 0
93 #define T_LEAF 1
94 #define NODE_TYPE_MASK 0x1UL
95 #define NODE_TYPE(node) ((node)->parent & NODE_TYPE_MASK)
97 #define IS_TNODE(n) (!(n->parent & T_LEAF))
98 #define IS_LEAF(n) (n->parent & T_LEAF)
100 struct node {
101 t_key key;
102 unsigned long parent;
105 struct leaf {
106 t_key key;
107 unsigned long parent;
108 struct hlist_head list;
109 struct rcu_head rcu;
112 struct leaf_info {
113 struct hlist_node hlist;
114 struct rcu_head rcu;
115 int plen;
116 struct list_head falh;
119 struct tnode {
120 t_key key;
121 unsigned long parent;
122 unsigned short pos:5; /* 2log(KEYLENGTH) bits needed */
123 unsigned short bits:5; /* 2log(KEYLENGTH) bits needed */
124 unsigned short full_children; /* KEYLENGTH bits needed */
125 unsigned short empty_children; /* KEYLENGTH bits needed */
126 struct rcu_head rcu;
127 struct node *child[0];
130 #ifdef CONFIG_IP_FIB_TRIE_STATS
131 struct trie_use_stats {
132 unsigned int gets;
133 unsigned int backtrack;
134 unsigned int semantic_match_passed;
135 unsigned int semantic_match_miss;
136 unsigned int null_node_hit;
137 unsigned int resize_node_skipped;
139 #endif
141 struct trie_stat {
142 unsigned int totdepth;
143 unsigned int maxdepth;
144 unsigned int tnodes;
145 unsigned int leaves;
146 unsigned int nullpointers;
147 unsigned int nodesizes[MAX_STAT_DEPTH];
150 struct trie {
151 struct node *trie;
152 #ifdef CONFIG_IP_FIB_TRIE_STATS
153 struct trie_use_stats stats;
154 #endif
155 int size;
156 unsigned int revision;
159 static void put_child(struct trie *t, struct tnode *tn, int i, struct node *n);
160 static void tnode_put_child_reorg(struct tnode *tn, int i, struct node *n, int wasfull);
161 static struct node *resize(struct trie *t, struct tnode *tn);
162 static struct tnode *inflate(struct trie *t, struct tnode *tn);
163 static struct tnode *halve(struct trie *t, struct tnode *tn);
164 static void tnode_free(struct tnode *tn);
166 static struct kmem_cache *fn_alias_kmem __read_mostly;
167 static struct trie *trie_local = NULL, *trie_main = NULL;
169 static inline struct tnode *node_parent(struct node *node)
171 struct tnode *ret;
173 ret = (struct tnode *)(node->parent & ~NODE_TYPE_MASK);
174 return rcu_dereference(ret);
177 static inline void node_set_parent(struct node *node, struct tnode *ptr)
179 rcu_assign_pointer(node->parent,
180 (unsigned long)ptr | NODE_TYPE(node));
183 /* rcu_read_lock needs to be hold by caller from readside */
185 static inline struct node *tnode_get_child(struct tnode *tn, int i)
187 BUG_ON(i >= 1 << tn->bits);
189 return rcu_dereference(tn->child[i]);
192 static inline int tnode_child_length(const struct tnode *tn)
194 return 1 << tn->bits;
197 static inline t_key mask_pfx(t_key k, unsigned short l)
199 return (l == 0) ? 0 : k >> (KEYLENGTH-l) << (KEYLENGTH-l);
202 static inline t_key tkey_extract_bits(t_key a, int offset, int bits)
204 if (offset < KEYLENGTH)
205 return ((t_key)(a << offset)) >> (KEYLENGTH - bits);
206 else
207 return 0;
210 static inline int tkey_equals(t_key a, t_key b)
212 return a == b;
215 static inline int tkey_sub_equals(t_key a, int offset, int bits, t_key b)
217 if (bits == 0 || offset >= KEYLENGTH)
218 return 1;
219 bits = bits > KEYLENGTH ? KEYLENGTH : bits;
220 return ((a ^ b) << offset) >> (KEYLENGTH - bits) == 0;
223 static inline int tkey_mismatch(t_key a, int offset, t_key b)
225 t_key diff = a ^ b;
226 int i = offset;
228 if (!diff)
229 return 0;
230 while ((diff << i) >> (KEYLENGTH-1) == 0)
231 i++;
232 return i;
236 To understand this stuff, an understanding of keys and all their bits is
237 necessary. Every node in the trie has a key associated with it, but not
238 all of the bits in that key are significant.
240 Consider a node 'n' and its parent 'tp'.
242 If n is a leaf, every bit in its key is significant. Its presence is
243 necessitated by path compression, since during a tree traversal (when
244 searching for a leaf - unless we are doing an insertion) we will completely
245 ignore all skipped bits we encounter. Thus we need to verify, at the end of
246 a potentially successful search, that we have indeed been walking the
247 correct key path.
249 Note that we can never "miss" the correct key in the tree if present by
250 following the wrong path. Path compression ensures that segments of the key
251 that are the same for all keys with a given prefix are skipped, but the
252 skipped part *is* identical for each node in the subtrie below the skipped
253 bit! trie_insert() in this implementation takes care of that - note the
254 call to tkey_sub_equals() in trie_insert().
256 if n is an internal node - a 'tnode' here, the various parts of its key
257 have many different meanings.
259 Example:
260 _________________________________________________________________
261 | i | i | i | i | i | i | i | N | N | N | S | S | S | S | S | C |
262 -----------------------------------------------------------------
263 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15
265 _________________________________________________________________
266 | C | C | C | u | u | u | u | u | u | u | u | u | u | u | u | u |
267 -----------------------------------------------------------------
268 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31
270 tp->pos = 7
271 tp->bits = 3
272 n->pos = 15
273 n->bits = 4
275 First, let's just ignore the bits that come before the parent tp, that is
276 the bits from 0 to (tp->pos-1). They are *known* but at this point we do
277 not use them for anything.
279 The bits from (tp->pos) to (tp->pos + tp->bits - 1) - "N", above - are the
280 index into the parent's child array. That is, they will be used to find
281 'n' among tp's children.
283 The bits from (tp->pos + tp->bits) to (n->pos - 1) - "S" - are skipped bits
284 for the node n.
286 All the bits we have seen so far are significant to the node n. The rest
287 of the bits are really not needed or indeed known in n->key.
289 The bits from (n->pos) to (n->pos + n->bits - 1) - "C" - are the index into
290 n's child array, and will of course be different for each child.
293 The rest of the bits, from (n->pos + n->bits) onward, are completely unknown
294 at this point.
298 static inline void check_tnode(const struct tnode *tn)
300 WARN_ON(tn && tn->pos+tn->bits > 32);
303 static int halve_threshold = 25;
304 static int inflate_threshold = 50;
305 static int halve_threshold_root = 8;
306 static int inflate_threshold_root = 15;
309 static void __alias_free_mem(struct rcu_head *head)
311 struct fib_alias *fa = container_of(head, struct fib_alias, rcu);
312 kmem_cache_free(fn_alias_kmem, fa);
315 static inline void alias_free_mem_rcu(struct fib_alias *fa)
317 call_rcu(&fa->rcu, __alias_free_mem);
320 static void __leaf_free_rcu(struct rcu_head *head)
322 kfree(container_of(head, struct leaf, rcu));
325 static void __leaf_info_free_rcu(struct rcu_head *head)
327 kfree(container_of(head, struct leaf_info, rcu));
330 static inline void free_leaf_info(struct leaf_info *leaf)
332 call_rcu(&leaf->rcu, __leaf_info_free_rcu);
335 static struct tnode *tnode_alloc(unsigned int size)
337 struct page *pages;
339 if (size <= PAGE_SIZE)
340 return kcalloc(size, 1, GFP_KERNEL);
342 pages = alloc_pages(GFP_KERNEL|__GFP_ZERO, get_order(size));
343 if (!pages)
344 return NULL;
346 return page_address(pages);
349 static void __tnode_free_rcu(struct rcu_head *head)
351 struct tnode *tn = container_of(head, struct tnode, rcu);
352 unsigned int size = sizeof(struct tnode) +
353 (1 << tn->bits) * sizeof(struct node *);
355 if (size <= PAGE_SIZE)
356 kfree(tn);
357 else
358 free_pages((unsigned long)tn, get_order(size));
361 static inline void tnode_free(struct tnode *tn)
363 if (IS_LEAF(tn)) {
364 struct leaf *l = (struct leaf *) tn;
365 call_rcu_bh(&l->rcu, __leaf_free_rcu);
366 } else
367 call_rcu(&tn->rcu, __tnode_free_rcu);
370 static struct leaf *leaf_new(void)
372 struct leaf *l = kmalloc(sizeof(struct leaf), GFP_KERNEL);
373 if (l) {
374 l->parent = T_LEAF;
375 INIT_HLIST_HEAD(&l->list);
377 return l;
380 static struct leaf_info *leaf_info_new(int plen)
382 struct leaf_info *li = kmalloc(sizeof(struct leaf_info), GFP_KERNEL);
383 if (li) {
384 li->plen = plen;
385 INIT_LIST_HEAD(&li->falh);
387 return li;
390 static struct tnode* tnode_new(t_key key, int pos, int bits)
392 int nchildren = 1<<bits;
393 int sz = sizeof(struct tnode) + nchildren * sizeof(struct node *);
394 struct tnode *tn = tnode_alloc(sz);
396 if (tn) {
397 memset(tn, 0, sz);
398 tn->parent = T_TNODE;
399 tn->pos = pos;
400 tn->bits = bits;
401 tn->key = key;
402 tn->full_children = 0;
403 tn->empty_children = 1<<bits;
406 pr_debug("AT %p s=%u %u\n", tn, (unsigned int) sizeof(struct tnode),
407 (unsigned int) (sizeof(struct node) * 1<<bits));
408 return tn;
412 * Check whether a tnode 'n' is "full", i.e. it is an internal node
413 * and no bits are skipped. See discussion in dyntree paper p. 6
416 static inline int tnode_full(const struct tnode *tn, const struct node *n)
418 if (n == NULL || IS_LEAF(n))
419 return 0;
421 return ((struct tnode *) n)->pos == tn->pos + tn->bits;
424 static inline void put_child(struct trie *t, struct tnode *tn, int i, struct node *n)
426 tnode_put_child_reorg(tn, i, n, -1);
430 * Add a child at position i overwriting the old value.
431 * Update the value of full_children and empty_children.
434 static void tnode_put_child_reorg(struct tnode *tn, int i, struct node *n, int wasfull)
436 struct node *chi = tn->child[i];
437 int isfull;
439 BUG_ON(i >= 1<<tn->bits);
442 /* update emptyChildren */
443 if (n == NULL && chi != NULL)
444 tn->empty_children++;
445 else if (n != NULL && chi == NULL)
446 tn->empty_children--;
448 /* update fullChildren */
449 if (wasfull == -1)
450 wasfull = tnode_full(tn, chi);
452 isfull = tnode_full(tn, n);
453 if (wasfull && !isfull)
454 tn->full_children--;
455 else if (!wasfull && isfull)
456 tn->full_children++;
458 if (n)
459 node_set_parent(n, tn);
461 rcu_assign_pointer(tn->child[i], n);
464 static struct node *resize(struct trie *t, struct tnode *tn)
466 int i;
467 int err = 0;
468 struct tnode *old_tn;
469 int inflate_threshold_use;
470 int halve_threshold_use;
471 int max_resize;
473 if (!tn)
474 return NULL;
476 pr_debug("In tnode_resize %p inflate_threshold=%d threshold=%d\n",
477 tn, inflate_threshold, halve_threshold);
479 /* No children */
480 if (tn->empty_children == tnode_child_length(tn)) {
481 tnode_free(tn);
482 return NULL;
484 /* One child */
485 if (tn->empty_children == tnode_child_length(tn) - 1)
486 for (i = 0; i < tnode_child_length(tn); i++) {
487 struct node *n;
489 n = tn->child[i];
490 if (!n)
491 continue;
493 /* compress one level */
494 node_set_parent(n, NULL);
495 tnode_free(tn);
496 return n;
499 * Double as long as the resulting node has a number of
500 * nonempty nodes that are above the threshold.
504 * From "Implementing a dynamic compressed trie" by Stefan Nilsson of
505 * the Helsinki University of Technology and Matti Tikkanen of Nokia
506 * Telecommunications, page 6:
507 * "A node is doubled if the ratio of non-empty children to all
508 * children in the *doubled* node is at least 'high'."
510 * 'high' in this instance is the variable 'inflate_threshold'. It
511 * is expressed as a percentage, so we multiply it with
512 * tnode_child_length() and instead of multiplying by 2 (since the
513 * child array will be doubled by inflate()) and multiplying
514 * the left-hand side by 100 (to handle the percentage thing) we
515 * multiply the left-hand side by 50.
517 * The left-hand side may look a bit weird: tnode_child_length(tn)
518 * - tn->empty_children is of course the number of non-null children
519 * in the current node. tn->full_children is the number of "full"
520 * children, that is non-null tnodes with a skip value of 0.
521 * All of those will be doubled in the resulting inflated tnode, so
522 * we just count them one extra time here.
524 * A clearer way to write this would be:
526 * to_be_doubled = tn->full_children;
527 * not_to_be_doubled = tnode_child_length(tn) - tn->empty_children -
528 * tn->full_children;
530 * new_child_length = tnode_child_length(tn) * 2;
532 * new_fill_factor = 100 * (not_to_be_doubled + 2*to_be_doubled) /
533 * new_child_length;
534 * if (new_fill_factor >= inflate_threshold)
536 * ...and so on, tho it would mess up the while () loop.
538 * anyway,
539 * 100 * (not_to_be_doubled + 2*to_be_doubled) / new_child_length >=
540 * inflate_threshold
542 * avoid a division:
543 * 100 * (not_to_be_doubled + 2*to_be_doubled) >=
544 * inflate_threshold * new_child_length
546 * expand not_to_be_doubled and to_be_doubled, and shorten:
547 * 100 * (tnode_child_length(tn) - tn->empty_children +
548 * tn->full_children) >= inflate_threshold * new_child_length
550 * expand new_child_length:
551 * 100 * (tnode_child_length(tn) - tn->empty_children +
552 * tn->full_children) >=
553 * inflate_threshold * tnode_child_length(tn) * 2
555 * shorten again:
556 * 50 * (tn->full_children + tnode_child_length(tn) -
557 * tn->empty_children) >= inflate_threshold *
558 * tnode_child_length(tn)
562 check_tnode(tn);
564 /* Keep root node larger */
566 if (!tn->parent)
567 inflate_threshold_use = inflate_threshold_root;
568 else
569 inflate_threshold_use = inflate_threshold;
571 err = 0;
572 max_resize = 10;
573 while ((tn->full_children > 0 && max_resize-- &&
574 50 * (tn->full_children + tnode_child_length(tn) - tn->empty_children) >=
575 inflate_threshold_use * tnode_child_length(tn))) {
577 old_tn = tn;
578 tn = inflate(t, tn);
579 if (IS_ERR(tn)) {
580 tn = old_tn;
581 #ifdef CONFIG_IP_FIB_TRIE_STATS
582 t->stats.resize_node_skipped++;
583 #endif
584 break;
588 if (max_resize < 0) {
589 if (!tn->parent)
590 printk(KERN_WARNING "Fix inflate_threshold_root. Now=%d size=%d bits\n",
591 inflate_threshold_root, tn->bits);
592 else
593 printk(KERN_WARNING "Fix inflate_threshold. Now=%d size=%d bits\n",
594 inflate_threshold, tn->bits);
597 check_tnode(tn);
600 * Halve as long as the number of empty children in this
601 * node is above threshold.
605 /* Keep root node larger */
607 if (!tn->parent)
608 halve_threshold_use = halve_threshold_root;
609 else
610 halve_threshold_use = halve_threshold;
612 err = 0;
613 max_resize = 10;
614 while (tn->bits > 1 && max_resize-- &&
615 100 * (tnode_child_length(tn) - tn->empty_children) <
616 halve_threshold_use * tnode_child_length(tn)) {
618 old_tn = tn;
619 tn = halve(t, tn);
620 if (IS_ERR(tn)) {
621 tn = old_tn;
622 #ifdef CONFIG_IP_FIB_TRIE_STATS
623 t->stats.resize_node_skipped++;
624 #endif
625 break;
629 if (max_resize < 0) {
630 if (!tn->parent)
631 printk(KERN_WARNING "Fix halve_threshold_root. Now=%d size=%d bits\n",
632 halve_threshold_root, tn->bits);
633 else
634 printk(KERN_WARNING "Fix halve_threshold. Now=%d size=%d bits\n",
635 halve_threshold, tn->bits);
638 /* Only one child remains */
639 if (tn->empty_children == tnode_child_length(tn) - 1)
640 for (i = 0; i < tnode_child_length(tn); i++) {
641 struct node *n;
643 n = tn->child[i];
644 if (!n)
645 continue;
647 /* compress one level */
649 node_set_parent(n, NULL);
650 tnode_free(tn);
651 return n;
654 return (struct node *) tn;
657 static struct tnode *inflate(struct trie *t, struct tnode *tn)
659 struct tnode *inode;
660 struct tnode *oldtnode = tn;
661 int olen = tnode_child_length(tn);
662 int i;
664 pr_debug("In inflate\n");
666 tn = tnode_new(oldtnode->key, oldtnode->pos, oldtnode->bits + 1);
668 if (!tn)
669 return ERR_PTR(-ENOMEM);
672 * Preallocate and store tnodes before the actual work so we
673 * don't get into an inconsistent state if memory allocation
674 * fails. In case of failure we return the oldnode and inflate
675 * of tnode is ignored.
678 for (i = 0; i < olen; i++) {
679 struct tnode *inode = (struct tnode *) tnode_get_child(oldtnode, i);
681 if (inode &&
682 IS_TNODE(inode) &&
683 inode->pos == oldtnode->pos + oldtnode->bits &&
684 inode->bits > 1) {
685 struct tnode *left, *right;
686 t_key m = ~0U << (KEYLENGTH - 1) >> inode->pos;
688 left = tnode_new(inode->key&(~m), inode->pos + 1,
689 inode->bits - 1);
690 if (!left)
691 goto nomem;
693 right = tnode_new(inode->key|m, inode->pos + 1,
694 inode->bits - 1);
696 if (!right) {
697 tnode_free(left);
698 goto nomem;
701 put_child(t, tn, 2*i, (struct node *) left);
702 put_child(t, tn, 2*i+1, (struct node *) right);
706 for (i = 0; i < olen; i++) {
707 struct node *node = tnode_get_child(oldtnode, i);
708 struct tnode *left, *right;
709 int size, j;
711 /* An empty child */
712 if (node == NULL)
713 continue;
715 /* A leaf or an internal node with skipped bits */
717 if (IS_LEAF(node) || ((struct tnode *) node)->pos >
718 tn->pos + tn->bits - 1) {
719 if (tkey_extract_bits(node->key, oldtnode->pos + oldtnode->bits,
720 1) == 0)
721 put_child(t, tn, 2*i, node);
722 else
723 put_child(t, tn, 2*i+1, node);
724 continue;
727 /* An internal node with two children */
728 inode = (struct tnode *) node;
730 if (inode->bits == 1) {
731 put_child(t, tn, 2*i, inode->child[0]);
732 put_child(t, tn, 2*i+1, inode->child[1]);
734 tnode_free(inode);
735 continue;
738 /* An internal node with more than two children */
740 /* We will replace this node 'inode' with two new
741 * ones, 'left' and 'right', each with half of the
742 * original children. The two new nodes will have
743 * a position one bit further down the key and this
744 * means that the "significant" part of their keys
745 * (see the discussion near the top of this file)
746 * will differ by one bit, which will be "0" in
747 * left's key and "1" in right's key. Since we are
748 * moving the key position by one step, the bit that
749 * we are moving away from - the bit at position
750 * (inode->pos) - is the one that will differ between
751 * left and right. So... we synthesize that bit in the
752 * two new keys.
753 * The mask 'm' below will be a single "one" bit at
754 * the position (inode->pos)
757 /* Use the old key, but set the new significant
758 * bit to zero.
761 left = (struct tnode *) tnode_get_child(tn, 2*i);
762 put_child(t, tn, 2*i, NULL);
764 BUG_ON(!left);
766 right = (struct tnode *) tnode_get_child(tn, 2*i+1);
767 put_child(t, tn, 2*i+1, NULL);
769 BUG_ON(!right);
771 size = tnode_child_length(left);
772 for (j = 0; j < size; j++) {
773 put_child(t, left, j, inode->child[j]);
774 put_child(t, right, j, inode->child[j + size]);
776 put_child(t, tn, 2*i, resize(t, left));
777 put_child(t, tn, 2*i+1, resize(t, right));
779 tnode_free(inode);
781 tnode_free(oldtnode);
782 return tn;
783 nomem:
785 int size = tnode_child_length(tn);
786 int j;
788 for (j = 0; j < size; j++)
789 if (tn->child[j])
790 tnode_free((struct tnode *)tn->child[j]);
792 tnode_free(tn);
794 return ERR_PTR(-ENOMEM);
798 static struct tnode *halve(struct trie *t, struct tnode *tn)
800 struct tnode *oldtnode = tn;
801 struct node *left, *right;
802 int i;
803 int olen = tnode_child_length(tn);
805 pr_debug("In halve\n");
807 tn = tnode_new(oldtnode->key, oldtnode->pos, oldtnode->bits - 1);
809 if (!tn)
810 return ERR_PTR(-ENOMEM);
813 * Preallocate and store tnodes before the actual work so we
814 * don't get into an inconsistent state if memory allocation
815 * fails. In case of failure we return the oldnode and halve
816 * of tnode is ignored.
819 for (i = 0; i < olen; i += 2) {
820 left = tnode_get_child(oldtnode, i);
821 right = tnode_get_child(oldtnode, i+1);
823 /* Two nonempty children */
824 if (left && right) {
825 struct tnode *newn;
827 newn = tnode_new(left->key, tn->pos + tn->bits, 1);
829 if (!newn)
830 goto nomem;
832 put_child(t, tn, i/2, (struct node *)newn);
837 for (i = 0; i < olen; i += 2) {
838 struct tnode *newBinNode;
840 left = tnode_get_child(oldtnode, i);
841 right = tnode_get_child(oldtnode, i+1);
843 /* At least one of the children is empty */
844 if (left == NULL) {
845 if (right == NULL) /* Both are empty */
846 continue;
847 put_child(t, tn, i/2, right);
848 continue;
851 if (right == NULL) {
852 put_child(t, tn, i/2, left);
853 continue;
856 /* Two nonempty children */
857 newBinNode = (struct tnode *) tnode_get_child(tn, i/2);
858 put_child(t, tn, i/2, NULL);
859 put_child(t, newBinNode, 0, left);
860 put_child(t, newBinNode, 1, right);
861 put_child(t, tn, i/2, resize(t, newBinNode));
863 tnode_free(oldtnode);
864 return tn;
865 nomem:
867 int size = tnode_child_length(tn);
868 int j;
870 for (j = 0; j < size; j++)
871 if (tn->child[j])
872 tnode_free((struct tnode *)tn->child[j]);
874 tnode_free(tn);
876 return ERR_PTR(-ENOMEM);
880 static void trie_init(struct trie *t)
882 if (!t)
883 return;
885 t->size = 0;
886 rcu_assign_pointer(t->trie, NULL);
887 t->revision = 0;
888 #ifdef CONFIG_IP_FIB_TRIE_STATS
889 memset(&t->stats, 0, sizeof(struct trie_use_stats));
890 #endif
893 /* readside must use rcu_read_lock currently dump routines
894 via get_fa_head and dump */
896 static struct leaf_info *find_leaf_info(struct leaf *l, int plen)
898 struct hlist_head *head = &l->list;
899 struct hlist_node *node;
900 struct leaf_info *li;
902 hlist_for_each_entry_rcu(li, node, head, hlist)
903 if (li->plen == plen)
904 return li;
906 return NULL;
909 static inline struct list_head * get_fa_head(struct leaf *l, int plen)
911 struct leaf_info *li = find_leaf_info(l, plen);
913 if (!li)
914 return NULL;
916 return &li->falh;
919 static void insert_leaf_info(struct hlist_head *head, struct leaf_info *new)
921 struct leaf_info *li = NULL, *last = NULL;
922 struct hlist_node *node;
924 if (hlist_empty(head)) {
925 hlist_add_head_rcu(&new->hlist, head);
926 } else {
927 hlist_for_each_entry(li, node, head, hlist) {
928 if (new->plen > li->plen)
929 break;
931 last = li;
933 if (last)
934 hlist_add_after_rcu(&last->hlist, &new->hlist);
935 else
936 hlist_add_before_rcu(&new->hlist, &li->hlist);
940 /* rcu_read_lock needs to be hold by caller from readside */
942 static struct leaf *
943 fib_find_node(struct trie *t, u32 key)
945 int pos;
946 struct tnode *tn;
947 struct node *n;
949 pos = 0;
950 n = rcu_dereference(t->trie);
952 while (n != NULL && NODE_TYPE(n) == T_TNODE) {
953 tn = (struct tnode *) n;
955 check_tnode(tn);
957 if (tkey_sub_equals(tn->key, pos, tn->pos-pos, key)) {
958 pos = tn->pos + tn->bits;
959 n = tnode_get_child(tn, tkey_extract_bits(key, tn->pos, tn->bits));
960 } else
961 break;
963 /* Case we have found a leaf. Compare prefixes */
965 if (n != NULL && IS_LEAF(n) && tkey_equals(key, n->key))
966 return (struct leaf *)n;
968 return NULL;
971 static struct node *trie_rebalance(struct trie *t, struct tnode *tn)
973 int wasfull;
974 t_key cindex, key = tn->key;
975 struct tnode *tp;
977 while (tn != NULL && (tp = node_parent((struct node *)tn)) != NULL) {
978 cindex = tkey_extract_bits(key, tp->pos, tp->bits);
979 wasfull = tnode_full(tp, tnode_get_child(tp, cindex));
980 tn = (struct tnode *) resize (t, (struct tnode *)tn);
981 tnode_put_child_reorg((struct tnode *)tp, cindex,(struct node*)tn, wasfull);
983 tp = node_parent((struct node *) tn);
984 if (!tp)
985 break;
986 tn = tp;
989 /* Handle last (top) tnode */
990 if (IS_TNODE(tn))
991 tn = (struct tnode*) resize(t, (struct tnode *)tn);
993 return (struct node*) tn;
996 /* only used from updater-side */
998 static struct list_head *
999 fib_insert_node(struct trie *t, int *err, u32 key, int plen)
1001 int pos, newpos;
1002 struct tnode *tp = NULL, *tn = NULL;
1003 struct node *n;
1004 struct leaf *l;
1005 int missbit;
1006 struct list_head *fa_head = NULL;
1007 struct leaf_info *li;
1008 t_key cindex;
1010 pos = 0;
1011 n = t->trie;
1013 /* If we point to NULL, stop. Either the tree is empty and we should
1014 * just put a new leaf in if, or we have reached an empty child slot,
1015 * and we should just put our new leaf in that.
1016 * If we point to a T_TNODE, check if it matches our key. Note that
1017 * a T_TNODE might be skipping any number of bits - its 'pos' need
1018 * not be the parent's 'pos'+'bits'!
1020 * If it does match the current key, get pos/bits from it, extract
1021 * the index from our key, push the T_TNODE and walk the tree.
1023 * If it doesn't, we have to replace it with a new T_TNODE.
1025 * If we point to a T_LEAF, it might or might not have the same key
1026 * as we do. If it does, just change the value, update the T_LEAF's
1027 * value, and return it.
1028 * If it doesn't, we need to replace it with a T_TNODE.
1031 while (n != NULL && NODE_TYPE(n) == T_TNODE) {
1032 tn = (struct tnode *) n;
1034 check_tnode(tn);
1036 if (tkey_sub_equals(tn->key, pos, tn->pos-pos, key)) {
1037 tp = tn;
1038 pos = tn->pos + tn->bits;
1039 n = tnode_get_child(tn, tkey_extract_bits(key, tn->pos, tn->bits));
1041 BUG_ON(n && node_parent(n) != tn);
1042 } else
1043 break;
1047 * n ----> NULL, LEAF or TNODE
1049 * tp is n's (parent) ----> NULL or TNODE
1052 BUG_ON(tp && IS_LEAF(tp));
1054 /* Case 1: n is a leaf. Compare prefixes */
1056 if (n != NULL && IS_LEAF(n) && tkey_equals(key, n->key)) {
1057 struct leaf *l = (struct leaf *) n;
1059 li = leaf_info_new(plen);
1061 if (!li) {
1062 *err = -ENOMEM;
1063 goto err;
1066 fa_head = &li->falh;
1067 insert_leaf_info(&l->list, li);
1068 goto done;
1070 t->size++;
1071 l = leaf_new();
1073 if (!l) {
1074 *err = -ENOMEM;
1075 goto err;
1078 l->key = key;
1079 li = leaf_info_new(plen);
1081 if (!li) {
1082 tnode_free((struct tnode *) l);
1083 *err = -ENOMEM;
1084 goto err;
1087 fa_head = &li->falh;
1088 insert_leaf_info(&l->list, li);
1090 if (t->trie && n == NULL) {
1091 /* Case 2: n is NULL, and will just insert a new leaf */
1093 node_set_parent((struct node *)l, tp);
1095 cindex = tkey_extract_bits(key, tp->pos, tp->bits);
1096 put_child(t, (struct tnode *)tp, cindex, (struct node *)l);
1097 } else {
1098 /* Case 3: n is a LEAF or a TNODE and the key doesn't match. */
1100 * Add a new tnode here
1101 * first tnode need some special handling
1104 if (tp)
1105 pos = tp->pos+tp->bits;
1106 else
1107 pos = 0;
1109 if (n) {
1110 newpos = tkey_mismatch(key, pos, n->key);
1111 tn = tnode_new(n->key, newpos, 1);
1112 } else {
1113 newpos = 0;
1114 tn = tnode_new(key, newpos, 1); /* First tnode */
1117 if (!tn) {
1118 free_leaf_info(li);
1119 tnode_free((struct tnode *) l);
1120 *err = -ENOMEM;
1121 goto err;
1124 node_set_parent((struct node *)tn, tp);
1126 missbit = tkey_extract_bits(key, newpos, 1);
1127 put_child(t, tn, missbit, (struct node *)l);
1128 put_child(t, tn, 1-missbit, n);
1130 if (tp) {
1131 cindex = tkey_extract_bits(key, tp->pos, tp->bits);
1132 put_child(t, (struct tnode *)tp, cindex, (struct node *)tn);
1133 } else {
1134 rcu_assign_pointer(t->trie, (struct node *)tn); /* First tnode */
1135 tp = tn;
1139 if (tp && tp->pos + tp->bits > 32)
1140 printk(KERN_WARNING "fib_trie tp=%p pos=%d, bits=%d, key=%0x plen=%d\n",
1141 tp, tp->pos, tp->bits, key, plen);
1143 /* Rebalance the trie */
1145 rcu_assign_pointer(t->trie, trie_rebalance(t, tp));
1146 done:
1147 t->revision++;
1148 err:
1149 return fa_head;
1153 * Caller must hold RTNL.
1155 static int fn_trie_insert(struct fib_table *tb, struct fib_config *cfg)
1157 struct trie *t = (struct trie *) tb->tb_data;
1158 struct fib_alias *fa, *new_fa;
1159 struct list_head *fa_head = NULL;
1160 struct fib_info *fi;
1161 int plen = cfg->fc_dst_len;
1162 u8 tos = cfg->fc_tos;
1163 u32 key, mask;
1164 int err;
1165 struct leaf *l;
1167 if (plen > 32)
1168 return -EINVAL;
1170 key = ntohl(cfg->fc_dst);
1172 pr_debug("Insert table=%u %08x/%d\n", tb->tb_id, key, plen);
1174 mask = ntohl(inet_make_mask(plen));
1176 if (key & ~mask)
1177 return -EINVAL;
1179 key = key & mask;
1181 fi = fib_create_info(cfg);
1182 if (IS_ERR(fi)) {
1183 err = PTR_ERR(fi);
1184 goto err;
1187 l = fib_find_node(t, key);
1188 fa = NULL;
1190 if (l) {
1191 fa_head = get_fa_head(l, plen);
1192 fa = fib_find_alias(fa_head, tos, fi->fib_priority);
1195 /* Now fa, if non-NULL, points to the first fib alias
1196 * with the same keys [prefix,tos,priority], if such key already
1197 * exists or to the node before which we will insert new one.
1199 * If fa is NULL, we will need to allocate a new one and
1200 * insert to the head of f.
1202 * If f is NULL, no fib node matched the destination key
1203 * and we need to allocate a new one of those as well.
1206 if (fa && fa->fa_info->fib_priority == fi->fib_priority) {
1207 struct fib_alias *fa_orig;
1209 err = -EEXIST;
1210 if (cfg->fc_nlflags & NLM_F_EXCL)
1211 goto out;
1213 if (cfg->fc_nlflags & NLM_F_REPLACE) {
1214 struct fib_info *fi_drop;
1215 u8 state;
1217 err = -ENOBUFS;
1218 new_fa = kmem_cache_alloc(fn_alias_kmem, GFP_KERNEL);
1219 if (new_fa == NULL)
1220 goto out;
1222 fi_drop = fa->fa_info;
1223 new_fa->fa_tos = fa->fa_tos;
1224 new_fa->fa_info = fi;
1225 new_fa->fa_type = cfg->fc_type;
1226 new_fa->fa_scope = cfg->fc_scope;
1227 state = fa->fa_state;
1228 new_fa->fa_state &= ~FA_S_ACCESSED;
1230 list_replace_rcu(&fa->fa_list, &new_fa->fa_list);
1231 alias_free_mem_rcu(fa);
1233 fib_release_info(fi_drop);
1234 if (state & FA_S_ACCESSED)
1235 rt_cache_flush(-1);
1236 rtmsg_fib(RTM_NEWROUTE, htonl(key), new_fa, plen,
1237 tb->tb_id, &cfg->fc_nlinfo, NLM_F_REPLACE);
1239 goto succeeded;
1241 /* Error if we find a perfect match which
1242 * uses the same scope, type, and nexthop
1243 * information.
1245 fa_orig = fa;
1246 list_for_each_entry(fa, fa_orig->fa_list.prev, fa_list) {
1247 if (fa->fa_tos != tos)
1248 break;
1249 if (fa->fa_info->fib_priority != fi->fib_priority)
1250 break;
1251 if (fa->fa_type == cfg->fc_type &&
1252 fa->fa_scope == cfg->fc_scope &&
1253 fa->fa_info == fi) {
1254 goto out;
1257 if (!(cfg->fc_nlflags & NLM_F_APPEND))
1258 fa = fa_orig;
1260 err = -ENOENT;
1261 if (!(cfg->fc_nlflags & NLM_F_CREATE))
1262 goto out;
1264 err = -ENOBUFS;
1265 new_fa = kmem_cache_alloc(fn_alias_kmem, GFP_KERNEL);
1266 if (new_fa == NULL)
1267 goto out;
1269 new_fa->fa_info = fi;
1270 new_fa->fa_tos = tos;
1271 new_fa->fa_type = cfg->fc_type;
1272 new_fa->fa_scope = cfg->fc_scope;
1273 new_fa->fa_state = 0;
1275 * Insert new entry to the list.
1278 if (!fa_head) {
1279 err = 0;
1280 fa_head = fib_insert_node(t, &err, key, plen);
1281 if (err)
1282 goto out_free_new_fa;
1285 list_add_tail_rcu(&new_fa->fa_list,
1286 (fa ? &fa->fa_list : fa_head));
1288 rt_cache_flush(-1);
1289 rtmsg_fib(RTM_NEWROUTE, htonl(key), new_fa, plen, tb->tb_id,
1290 &cfg->fc_nlinfo, 0);
1291 succeeded:
1292 return 0;
1294 out_free_new_fa:
1295 kmem_cache_free(fn_alias_kmem, new_fa);
1296 out:
1297 fib_release_info(fi);
1298 err:
1299 return err;
1303 /* should be called with rcu_read_lock */
1304 static inline int check_leaf(struct trie *t, struct leaf *l,
1305 t_key key, int *plen, const struct flowi *flp,
1306 struct fib_result *res)
1308 int err, i;
1309 __be32 mask;
1310 struct leaf_info *li;
1311 struct hlist_head *hhead = &l->list;
1312 struct hlist_node *node;
1314 hlist_for_each_entry_rcu(li, node, hhead, hlist) {
1315 i = li->plen;
1316 mask = inet_make_mask(i);
1317 if (l->key != (key & ntohl(mask)))
1318 continue;
1320 if ((err = fib_semantic_match(&li->falh, flp, res, htonl(l->key), mask, i)) <= 0) {
1321 *plen = i;
1322 #ifdef CONFIG_IP_FIB_TRIE_STATS
1323 t->stats.semantic_match_passed++;
1324 #endif
1325 return err;
1327 #ifdef CONFIG_IP_FIB_TRIE_STATS
1328 t->stats.semantic_match_miss++;
1329 #endif
1331 return 1;
1334 static int
1335 fn_trie_lookup(struct fib_table *tb, const struct flowi *flp, struct fib_result *res)
1337 struct trie *t = (struct trie *) tb->tb_data;
1338 int plen, ret = 0;
1339 struct node *n;
1340 struct tnode *pn;
1341 int pos, bits;
1342 t_key key = ntohl(flp->fl4_dst);
1343 int chopped_off;
1344 t_key cindex = 0;
1345 int current_prefix_length = KEYLENGTH;
1346 struct tnode *cn;
1347 t_key node_prefix, key_prefix, pref_mismatch;
1348 int mp;
1350 rcu_read_lock();
1352 n = rcu_dereference(t->trie);
1353 if (!n)
1354 goto failed;
1356 #ifdef CONFIG_IP_FIB_TRIE_STATS
1357 t->stats.gets++;
1358 #endif
1360 /* Just a leaf? */
1361 if (IS_LEAF(n)) {
1362 if ((ret = check_leaf(t, (struct leaf *)n, key, &plen, flp, res)) <= 0)
1363 goto found;
1364 goto failed;
1366 pn = (struct tnode *) n;
1367 chopped_off = 0;
1369 while (pn) {
1370 pos = pn->pos;
1371 bits = pn->bits;
1373 if (!chopped_off)
1374 cindex = tkey_extract_bits(mask_pfx(key, current_prefix_length),
1375 pos, bits);
1377 n = tnode_get_child(pn, cindex);
1379 if (n == NULL) {
1380 #ifdef CONFIG_IP_FIB_TRIE_STATS
1381 t->stats.null_node_hit++;
1382 #endif
1383 goto backtrace;
1386 if (IS_LEAF(n)) {
1387 if ((ret = check_leaf(t, (struct leaf *)n, key, &plen, flp, res)) <= 0)
1388 goto found;
1389 else
1390 goto backtrace;
1393 #define HL_OPTIMIZE
1394 #ifdef HL_OPTIMIZE
1395 cn = (struct tnode *)n;
1398 * It's a tnode, and we can do some extra checks here if we
1399 * like, to avoid descending into a dead-end branch.
1400 * This tnode is in the parent's child array at index
1401 * key[p_pos..p_pos+p_bits] but potentially with some bits
1402 * chopped off, so in reality the index may be just a
1403 * subprefix, padded with zero at the end.
1404 * We can also take a look at any skipped bits in this
1405 * tnode - everything up to p_pos is supposed to be ok,
1406 * and the non-chopped bits of the index (se previous
1407 * paragraph) are also guaranteed ok, but the rest is
1408 * considered unknown.
1410 * The skipped bits are key[pos+bits..cn->pos].
1413 /* If current_prefix_length < pos+bits, we are already doing
1414 * actual prefix matching, which means everything from
1415 * pos+(bits-chopped_off) onward must be zero along some
1416 * branch of this subtree - otherwise there is *no* valid
1417 * prefix present. Here we can only check the skipped
1418 * bits. Remember, since we have already indexed into the
1419 * parent's child array, we know that the bits we chopped of
1420 * *are* zero.
1423 /* NOTA BENE: CHECKING ONLY SKIPPED BITS FOR THE NEW NODE HERE */
1425 if (current_prefix_length < pos+bits) {
1426 if (tkey_extract_bits(cn->key, current_prefix_length,
1427 cn->pos - current_prefix_length) != 0 ||
1428 !(cn->child[0]))
1429 goto backtrace;
1433 * If chopped_off=0, the index is fully validated and we
1434 * only need to look at the skipped bits for this, the new,
1435 * tnode. What we actually want to do is to find out if
1436 * these skipped bits match our key perfectly, or if we will
1437 * have to count on finding a matching prefix further down,
1438 * because if we do, we would like to have some way of
1439 * verifying the existence of such a prefix at this point.
1442 /* The only thing we can do at this point is to verify that
1443 * any such matching prefix can indeed be a prefix to our
1444 * key, and if the bits in the node we are inspecting that
1445 * do not match our key are not ZERO, this cannot be true.
1446 * Thus, find out where there is a mismatch (before cn->pos)
1447 * and verify that all the mismatching bits are zero in the
1448 * new tnode's key.
1451 /* Note: We aren't very concerned about the piece of the key
1452 * that precede pn->pos+pn->bits, since these have already been
1453 * checked. The bits after cn->pos aren't checked since these are
1454 * by definition "unknown" at this point. Thus, what we want to
1455 * see is if we are about to enter the "prefix matching" state,
1456 * and in that case verify that the skipped bits that will prevail
1457 * throughout this subtree are zero, as they have to be if we are
1458 * to find a matching prefix.
1461 node_prefix = mask_pfx(cn->key, cn->pos);
1462 key_prefix = mask_pfx(key, cn->pos);
1463 pref_mismatch = key_prefix^node_prefix;
1464 mp = 0;
1466 /* In short: If skipped bits in this node do not match the search
1467 * key, enter the "prefix matching" state.directly.
1469 if (pref_mismatch) {
1470 while (!(pref_mismatch & (1<<(KEYLENGTH-1)))) {
1471 mp++;
1472 pref_mismatch = pref_mismatch <<1;
1474 key_prefix = tkey_extract_bits(cn->key, mp, cn->pos-mp);
1476 if (key_prefix != 0)
1477 goto backtrace;
1479 if (current_prefix_length >= cn->pos)
1480 current_prefix_length = mp;
1482 #endif
1483 pn = (struct tnode *)n; /* Descend */
1484 chopped_off = 0;
1485 continue;
1487 backtrace:
1488 chopped_off++;
1490 /* As zero don't change the child key (cindex) */
1491 while ((chopped_off <= pn->bits) && !(cindex & (1<<(chopped_off-1))))
1492 chopped_off++;
1494 /* Decrease current_... with bits chopped off */
1495 if (current_prefix_length > pn->pos + pn->bits - chopped_off)
1496 current_prefix_length = pn->pos + pn->bits - chopped_off;
1499 * Either we do the actual chop off according or if we have
1500 * chopped off all bits in this tnode walk up to our parent.
1503 if (chopped_off <= pn->bits) {
1504 cindex &= ~(1 << (chopped_off-1));
1505 } else {
1506 struct tnode *parent = node_parent((struct node *) pn);
1507 if (!parent)
1508 goto failed;
1510 /* Get Child's index */
1511 cindex = tkey_extract_bits(pn->key, parent->pos, parent->bits);
1512 pn = parent;
1513 chopped_off = 0;
1515 #ifdef CONFIG_IP_FIB_TRIE_STATS
1516 t->stats.backtrack++;
1517 #endif
1518 goto backtrace;
1521 failed:
1522 ret = 1;
1523 found:
1524 rcu_read_unlock();
1525 return ret;
1528 /* only called from updater side */
1529 static int trie_leaf_remove(struct trie *t, t_key key)
1531 t_key cindex;
1532 struct tnode *tp = NULL;
1533 struct node *n = t->trie;
1534 struct leaf *l;
1536 pr_debug("entering trie_leaf_remove(%p)\n", n);
1538 /* Note that in the case skipped bits, those bits are *not* checked!
1539 * When we finish this, we will have NULL or a T_LEAF, and the
1540 * T_LEAF may or may not match our key.
1543 while (n != NULL && IS_TNODE(n)) {
1544 struct tnode *tn = (struct tnode *) n;
1545 check_tnode(tn);
1546 n = tnode_get_child(tn ,tkey_extract_bits(key, tn->pos, tn->bits));
1548 BUG_ON(n && node_parent(n) != tn);
1550 l = (struct leaf *) n;
1552 if (!n || !tkey_equals(l->key, key))
1553 return 0;
1556 * Key found.
1557 * Remove the leaf and rebalance the tree
1560 t->revision++;
1561 t->size--;
1563 tp = node_parent(n);
1564 tnode_free((struct tnode *) n);
1566 if (tp) {
1567 cindex = tkey_extract_bits(key, tp->pos, tp->bits);
1568 put_child(t, (struct tnode *)tp, cindex, NULL);
1569 rcu_assign_pointer(t->trie, trie_rebalance(t, tp));
1570 } else
1571 rcu_assign_pointer(t->trie, NULL);
1573 return 1;
1577 * Caller must hold RTNL.
1579 static int fn_trie_delete(struct fib_table *tb, struct fib_config *cfg)
1581 struct trie *t = (struct trie *) tb->tb_data;
1582 u32 key, mask;
1583 int plen = cfg->fc_dst_len;
1584 u8 tos = cfg->fc_tos;
1585 struct fib_alias *fa, *fa_to_delete;
1586 struct list_head *fa_head;
1587 struct leaf *l;
1588 struct leaf_info *li;
1590 if (plen > 32)
1591 return -EINVAL;
1593 key = ntohl(cfg->fc_dst);
1594 mask = ntohl(inet_make_mask(plen));
1596 if (key & ~mask)
1597 return -EINVAL;
1599 key = key & mask;
1600 l = fib_find_node(t, key);
1602 if (!l)
1603 return -ESRCH;
1605 fa_head = get_fa_head(l, plen);
1606 fa = fib_find_alias(fa_head, tos, 0);
1608 if (!fa)
1609 return -ESRCH;
1611 pr_debug("Deleting %08x/%d tos=%d t=%p\n", key, plen, tos, t);
1613 fa_to_delete = NULL;
1614 fa_head = fa->fa_list.prev;
1616 list_for_each_entry(fa, fa_head, fa_list) {
1617 struct fib_info *fi = fa->fa_info;
1619 if (fa->fa_tos != tos)
1620 break;
1622 if ((!cfg->fc_type || fa->fa_type == cfg->fc_type) &&
1623 (cfg->fc_scope == RT_SCOPE_NOWHERE ||
1624 fa->fa_scope == cfg->fc_scope) &&
1625 (!cfg->fc_protocol ||
1626 fi->fib_protocol == cfg->fc_protocol) &&
1627 fib_nh_match(cfg, fi) == 0) {
1628 fa_to_delete = fa;
1629 break;
1633 if (!fa_to_delete)
1634 return -ESRCH;
1636 fa = fa_to_delete;
1637 rtmsg_fib(RTM_DELROUTE, htonl(key), fa, plen, tb->tb_id,
1638 &cfg->fc_nlinfo, 0);
1640 l = fib_find_node(t, key);
1641 li = find_leaf_info(l, plen);
1643 list_del_rcu(&fa->fa_list);
1645 if (list_empty(fa_head)) {
1646 hlist_del_rcu(&li->hlist);
1647 free_leaf_info(li);
1650 if (hlist_empty(&l->list))
1651 trie_leaf_remove(t, key);
1653 if (fa->fa_state & FA_S_ACCESSED)
1654 rt_cache_flush(-1);
1656 fib_release_info(fa->fa_info);
1657 alias_free_mem_rcu(fa);
1658 return 0;
1661 static int trie_flush_list(struct trie *t, struct list_head *head)
1663 struct fib_alias *fa, *fa_node;
1664 int found = 0;
1666 list_for_each_entry_safe(fa, fa_node, head, fa_list) {
1667 struct fib_info *fi = fa->fa_info;
1669 if (fi && (fi->fib_flags & RTNH_F_DEAD)) {
1670 list_del_rcu(&fa->fa_list);
1671 fib_release_info(fa->fa_info);
1672 alias_free_mem_rcu(fa);
1673 found++;
1676 return found;
1679 static int trie_flush_leaf(struct trie *t, struct leaf *l)
1681 int found = 0;
1682 struct hlist_head *lih = &l->list;
1683 struct hlist_node *node, *tmp;
1684 struct leaf_info *li = NULL;
1686 hlist_for_each_entry_safe(li, node, tmp, lih, hlist) {
1687 found += trie_flush_list(t, &li->falh);
1689 if (list_empty(&li->falh)) {
1690 hlist_del_rcu(&li->hlist);
1691 free_leaf_info(li);
1694 return found;
1697 /* rcu_read_lock needs to be hold by caller from readside */
1699 static struct leaf *nextleaf(struct trie *t, struct leaf *thisleaf)
1701 struct node *c = (struct node *) thisleaf;
1702 struct tnode *p;
1703 int idx;
1704 struct node *trie = rcu_dereference(t->trie);
1706 if (c == NULL) {
1707 if (trie == NULL)
1708 return NULL;
1710 if (IS_LEAF(trie)) /* trie w. just a leaf */
1711 return (struct leaf *) trie;
1713 p = (struct tnode*) trie; /* Start */
1714 } else
1715 p = node_parent(c);
1717 while (p) {
1718 int pos, last;
1720 /* Find the next child of the parent */
1721 if (c)
1722 pos = 1 + tkey_extract_bits(c->key, p->pos, p->bits);
1723 else
1724 pos = 0;
1726 last = 1 << p->bits;
1727 for (idx = pos; idx < last ; idx++) {
1728 c = rcu_dereference(p->child[idx]);
1730 if (!c)
1731 continue;
1733 /* Decend if tnode */
1734 while (IS_TNODE(c)) {
1735 p = (struct tnode *) c;
1736 idx = 0;
1738 /* Rightmost non-NULL branch */
1739 if (p && IS_TNODE(p))
1740 while (!(c = rcu_dereference(p->child[idx]))
1741 && idx < (1<<p->bits)) idx++;
1743 /* Done with this tnode? */
1744 if (idx >= (1 << p->bits) || !c)
1745 goto up;
1747 return (struct leaf *) c;
1750 /* No more children go up one step */
1751 c = (struct node *) p;
1752 p = node_parent(c);
1754 return NULL; /* Ready. Root of trie */
1758 * Caller must hold RTNL.
1760 static int fn_trie_flush(struct fib_table *tb)
1762 struct trie *t = (struct trie *) tb->tb_data;
1763 struct leaf *ll = NULL, *l = NULL;
1764 int found = 0, h;
1766 t->revision++;
1768 for (h = 0; (l = nextleaf(t, l)) != NULL; h++) {
1769 found += trie_flush_leaf(t, l);
1771 if (ll && hlist_empty(&ll->list))
1772 trie_leaf_remove(t, ll->key);
1773 ll = l;
1776 if (ll && hlist_empty(&ll->list))
1777 trie_leaf_remove(t, ll->key);
1779 pr_debug("trie_flush found=%d\n", found);
1780 return found;
1783 static int trie_last_dflt = -1;
1785 static void
1786 fn_trie_select_default(struct fib_table *tb, const struct flowi *flp, struct fib_result *res)
1788 struct trie *t = (struct trie *) tb->tb_data;
1789 int order, last_idx;
1790 struct fib_info *fi = NULL;
1791 struct fib_info *last_resort;
1792 struct fib_alias *fa = NULL;
1793 struct list_head *fa_head;
1794 struct leaf *l;
1796 last_idx = -1;
1797 last_resort = NULL;
1798 order = -1;
1800 rcu_read_lock();
1802 l = fib_find_node(t, 0);
1803 if (!l)
1804 goto out;
1806 fa_head = get_fa_head(l, 0);
1807 if (!fa_head)
1808 goto out;
1810 if (list_empty(fa_head))
1811 goto out;
1813 list_for_each_entry_rcu(fa, fa_head, fa_list) {
1814 struct fib_info *next_fi = fa->fa_info;
1816 if (fa->fa_scope != res->scope ||
1817 fa->fa_type != RTN_UNICAST)
1818 continue;
1820 if (next_fi->fib_priority > res->fi->fib_priority)
1821 break;
1822 if (!next_fi->fib_nh[0].nh_gw ||
1823 next_fi->fib_nh[0].nh_scope != RT_SCOPE_LINK)
1824 continue;
1825 fa->fa_state |= FA_S_ACCESSED;
1827 if (fi == NULL) {
1828 if (next_fi != res->fi)
1829 break;
1830 } else if (!fib_detect_death(fi, order, &last_resort,
1831 &last_idx, &trie_last_dflt)) {
1832 if (res->fi)
1833 fib_info_put(res->fi);
1834 res->fi = fi;
1835 atomic_inc(&fi->fib_clntref);
1836 trie_last_dflt = order;
1837 goto out;
1839 fi = next_fi;
1840 order++;
1842 if (order <= 0 || fi == NULL) {
1843 trie_last_dflt = -1;
1844 goto out;
1847 if (!fib_detect_death(fi, order, &last_resort, &last_idx, &trie_last_dflt)) {
1848 if (res->fi)
1849 fib_info_put(res->fi);
1850 res->fi = fi;
1851 atomic_inc(&fi->fib_clntref);
1852 trie_last_dflt = order;
1853 goto out;
1855 if (last_idx >= 0) {
1856 if (res->fi)
1857 fib_info_put(res->fi);
1858 res->fi = last_resort;
1859 if (last_resort)
1860 atomic_inc(&last_resort->fib_clntref);
1862 trie_last_dflt = last_idx;
1863 out:;
1864 rcu_read_unlock();
1867 static int fn_trie_dump_fa(t_key key, int plen, struct list_head *fah, struct fib_table *tb,
1868 struct sk_buff *skb, struct netlink_callback *cb)
1870 int i, s_i;
1871 struct fib_alias *fa;
1873 __be32 xkey = htonl(key);
1875 s_i = cb->args[4];
1876 i = 0;
1878 /* rcu_read_lock is hold by caller */
1880 list_for_each_entry_rcu(fa, fah, fa_list) {
1881 if (i < s_i) {
1882 i++;
1883 continue;
1885 BUG_ON(!fa->fa_info);
1887 if (fib_dump_info(skb, NETLINK_CB(cb->skb).pid,
1888 cb->nlh->nlmsg_seq,
1889 RTM_NEWROUTE,
1890 tb->tb_id,
1891 fa->fa_type,
1892 fa->fa_scope,
1893 xkey,
1894 plen,
1895 fa->fa_tos,
1896 fa->fa_info, 0) < 0) {
1897 cb->args[4] = i;
1898 return -1;
1900 i++;
1902 cb->args[4] = i;
1903 return skb->len;
1906 static int fn_trie_dump_plen(struct trie *t, int plen, struct fib_table *tb, struct sk_buff *skb,
1907 struct netlink_callback *cb)
1909 int h, s_h;
1910 struct list_head *fa_head;
1911 struct leaf *l = NULL;
1913 s_h = cb->args[3];
1915 for (h = 0; (l = nextleaf(t, l)) != NULL; h++) {
1916 if (h < s_h)
1917 continue;
1918 if (h > s_h)
1919 memset(&cb->args[4], 0,
1920 sizeof(cb->args) - 4*sizeof(cb->args[0]));
1922 fa_head = get_fa_head(l, plen);
1924 if (!fa_head)
1925 continue;
1927 if (list_empty(fa_head))
1928 continue;
1930 if (fn_trie_dump_fa(l->key, plen, fa_head, tb, skb, cb)<0) {
1931 cb->args[3] = h;
1932 return -1;
1935 cb->args[3] = h;
1936 return skb->len;
1939 static int fn_trie_dump(struct fib_table *tb, struct sk_buff *skb, struct netlink_callback *cb)
1941 int m, s_m;
1942 struct trie *t = (struct trie *) tb->tb_data;
1944 s_m = cb->args[2];
1946 rcu_read_lock();
1947 for (m = 0; m <= 32; m++) {
1948 if (m < s_m)
1949 continue;
1950 if (m > s_m)
1951 memset(&cb->args[3], 0,
1952 sizeof(cb->args) - 3*sizeof(cb->args[0]));
1954 if (fn_trie_dump_plen(t, 32-m, tb, skb, cb)<0) {
1955 cb->args[2] = m;
1956 goto out;
1959 rcu_read_unlock();
1960 cb->args[2] = m;
1961 return skb->len;
1962 out:
1963 rcu_read_unlock();
1964 return -1;
1967 /* Fix more generic FIB names for init later */
1969 #ifdef CONFIG_IP_MULTIPLE_TABLES
1970 struct fib_table * fib_hash_init(u32 id)
1971 #else
1972 struct fib_table * __init fib_hash_init(u32 id)
1973 #endif
1975 struct fib_table *tb;
1976 struct trie *t;
1978 if (fn_alias_kmem == NULL)
1979 fn_alias_kmem = kmem_cache_create("ip_fib_alias",
1980 sizeof(struct fib_alias),
1981 0, SLAB_HWCACHE_ALIGN,
1982 NULL);
1984 tb = kmalloc(sizeof(struct fib_table) + sizeof(struct trie),
1985 GFP_KERNEL);
1986 if (tb == NULL)
1987 return NULL;
1989 tb->tb_id = id;
1990 tb->tb_lookup = fn_trie_lookup;
1991 tb->tb_insert = fn_trie_insert;
1992 tb->tb_delete = fn_trie_delete;
1993 tb->tb_flush = fn_trie_flush;
1994 tb->tb_select_default = fn_trie_select_default;
1995 tb->tb_dump = fn_trie_dump;
1996 memset(tb->tb_data, 0, sizeof(struct trie));
1998 t = (struct trie *) tb->tb_data;
2000 trie_init(t);
2002 if (id == RT_TABLE_LOCAL)
2003 trie_local = t;
2004 else if (id == RT_TABLE_MAIN)
2005 trie_main = t;
2007 if (id == RT_TABLE_LOCAL)
2008 printk(KERN_INFO "IPv4 FIB: Using LC-trie version %s\n", VERSION);
2010 return tb;
2013 #ifdef CONFIG_PROC_FS
2014 /* Depth first Trie walk iterator */
2015 struct fib_trie_iter {
2016 struct tnode *tnode;
2017 struct trie *trie;
2018 unsigned index;
2019 unsigned depth;
2022 static struct node *fib_trie_get_next(struct fib_trie_iter *iter)
2024 struct tnode *tn = iter->tnode;
2025 unsigned cindex = iter->index;
2026 struct tnode *p;
2028 /* A single entry routing table */
2029 if (!tn)
2030 return NULL;
2032 pr_debug("get_next iter={node=%p index=%d depth=%d}\n",
2033 iter->tnode, iter->index, iter->depth);
2034 rescan:
2035 while (cindex < (1<<tn->bits)) {
2036 struct node *n = tnode_get_child(tn, cindex);
2038 if (n) {
2039 if (IS_LEAF(n)) {
2040 iter->tnode = tn;
2041 iter->index = cindex + 1;
2042 } else {
2043 /* push down one level */
2044 iter->tnode = (struct tnode *) n;
2045 iter->index = 0;
2046 ++iter->depth;
2048 return n;
2051 ++cindex;
2054 /* Current node exhausted, pop back up */
2055 p = node_parent((struct node *)tn);
2056 if (p) {
2057 cindex = tkey_extract_bits(tn->key, p->pos, p->bits)+1;
2058 tn = p;
2059 --iter->depth;
2060 goto rescan;
2063 /* got root? */
2064 return NULL;
2067 static struct node *fib_trie_get_first(struct fib_trie_iter *iter,
2068 struct trie *t)
2070 struct node *n ;
2072 if (!t)
2073 return NULL;
2075 n = rcu_dereference(t->trie);
2077 if (!iter)
2078 return NULL;
2080 if (n) {
2081 if (IS_TNODE(n)) {
2082 iter->tnode = (struct tnode *) n;
2083 iter->trie = t;
2084 iter->index = 0;
2085 iter->depth = 1;
2086 } else {
2087 iter->tnode = NULL;
2088 iter->trie = t;
2089 iter->index = 0;
2090 iter->depth = 0;
2092 return n;
2094 return NULL;
2097 static void trie_collect_stats(struct trie *t, struct trie_stat *s)
2099 struct node *n;
2100 struct fib_trie_iter iter;
2102 memset(s, 0, sizeof(*s));
2104 rcu_read_lock();
2105 for (n = fib_trie_get_first(&iter, t); n;
2106 n = fib_trie_get_next(&iter)) {
2107 if (IS_LEAF(n)) {
2108 s->leaves++;
2109 s->totdepth += iter.depth;
2110 if (iter.depth > s->maxdepth)
2111 s->maxdepth = iter.depth;
2112 } else {
2113 const struct tnode *tn = (const struct tnode *) n;
2114 int i;
2116 s->tnodes++;
2117 if (tn->bits < MAX_STAT_DEPTH)
2118 s->nodesizes[tn->bits]++;
2120 for (i = 0; i < (1<<tn->bits); i++)
2121 if (!tn->child[i])
2122 s->nullpointers++;
2125 rcu_read_unlock();
2129 * This outputs /proc/net/fib_triestats
2131 static void trie_show_stats(struct seq_file *seq, struct trie_stat *stat)
2133 unsigned i, max, pointers, bytes, avdepth;
2135 if (stat->leaves)
2136 avdepth = stat->totdepth*100 / stat->leaves;
2137 else
2138 avdepth = 0;
2140 seq_printf(seq, "\tAver depth: %d.%02d\n", avdepth / 100, avdepth % 100 );
2141 seq_printf(seq, "\tMax depth: %u\n", stat->maxdepth);
2143 seq_printf(seq, "\tLeaves: %u\n", stat->leaves);
2145 bytes = sizeof(struct leaf) * stat->leaves;
2146 seq_printf(seq, "\tInternal nodes: %d\n\t", stat->tnodes);
2147 bytes += sizeof(struct tnode) * stat->tnodes;
2149 max = MAX_STAT_DEPTH;
2150 while (max > 0 && stat->nodesizes[max-1] == 0)
2151 max--;
2153 pointers = 0;
2154 for (i = 1; i <= max; i++)
2155 if (stat->nodesizes[i] != 0) {
2156 seq_printf(seq, " %d: %d", i, stat->nodesizes[i]);
2157 pointers += (1<<i) * stat->nodesizes[i];
2159 seq_putc(seq, '\n');
2160 seq_printf(seq, "\tPointers: %d\n", pointers);
2162 bytes += sizeof(struct node *) * pointers;
2163 seq_printf(seq, "Null ptrs: %d\n", stat->nullpointers);
2164 seq_printf(seq, "Total size: %d kB\n", (bytes + 1023) / 1024);
2166 #ifdef CONFIG_IP_FIB_TRIE_STATS
2167 seq_printf(seq, "Counters:\n---------\n");
2168 seq_printf(seq,"gets = %d\n", t->stats.gets);
2169 seq_printf(seq,"backtracks = %d\n", t->stats.backtrack);
2170 seq_printf(seq,"semantic match passed = %d\n", t->stats.semantic_match_passed);
2171 seq_printf(seq,"semantic match miss = %d\n", t->stats.semantic_match_miss);
2172 seq_printf(seq,"null node hit= %d\n", t->stats.null_node_hit);
2173 seq_printf(seq,"skipped node resize = %d\n", t->stats.resize_node_skipped);
2174 #ifdef CLEAR_STATS
2175 memset(&(t->stats), 0, sizeof(t->stats));
2176 #endif
2177 #endif /* CONFIG_IP_FIB_TRIE_STATS */
2180 static int fib_triestat_seq_show(struct seq_file *seq, void *v)
2182 struct trie_stat *stat;
2184 stat = kmalloc(sizeof(*stat), GFP_KERNEL);
2185 if (!stat)
2186 return -ENOMEM;
2188 seq_printf(seq, "Basic info: size of leaf: %Zd bytes, size of tnode: %Zd bytes.\n",
2189 sizeof(struct leaf), sizeof(struct tnode));
2191 if (trie_local) {
2192 seq_printf(seq, "Local:\n");
2193 trie_collect_stats(trie_local, stat);
2194 trie_show_stats(seq, stat);
2197 if (trie_main) {
2198 seq_printf(seq, "Main:\n");
2199 trie_collect_stats(trie_main, stat);
2200 trie_show_stats(seq, stat);
2202 kfree(stat);
2204 return 0;
2207 static int fib_triestat_seq_open(struct inode *inode, struct file *file)
2209 return single_open(file, fib_triestat_seq_show, NULL);
2212 static const struct file_operations fib_triestat_fops = {
2213 .owner = THIS_MODULE,
2214 .open = fib_triestat_seq_open,
2215 .read = seq_read,
2216 .llseek = seq_lseek,
2217 .release = single_release,
2220 static struct node *fib_trie_get_idx(struct fib_trie_iter *iter,
2221 loff_t pos)
2223 loff_t idx = 0;
2224 struct node *n;
2226 for (n = fib_trie_get_first(iter, trie_local);
2227 n; ++idx, n = fib_trie_get_next(iter)) {
2228 if (pos == idx)
2229 return n;
2232 for (n = fib_trie_get_first(iter, trie_main);
2233 n; ++idx, n = fib_trie_get_next(iter)) {
2234 if (pos == idx)
2235 return n;
2237 return NULL;
2240 static void *fib_trie_seq_start(struct seq_file *seq, loff_t *pos)
2242 rcu_read_lock();
2243 if (*pos == 0)
2244 return SEQ_START_TOKEN;
2245 return fib_trie_get_idx(seq->private, *pos - 1);
2248 static void *fib_trie_seq_next(struct seq_file *seq, void *v, loff_t *pos)
2250 struct fib_trie_iter *iter = seq->private;
2251 void *l = v;
2253 ++*pos;
2254 if (v == SEQ_START_TOKEN)
2255 return fib_trie_get_idx(iter, 0);
2257 v = fib_trie_get_next(iter);
2258 BUG_ON(v == l);
2259 if (v)
2260 return v;
2262 /* continue scan in next trie */
2263 if (iter->trie == trie_local)
2264 return fib_trie_get_first(iter, trie_main);
2266 return NULL;
2269 static void fib_trie_seq_stop(struct seq_file *seq, void *v)
2271 rcu_read_unlock();
2274 static void seq_indent(struct seq_file *seq, int n)
2276 while (n-- > 0) seq_puts(seq, " ");
2279 static inline const char *rtn_scope(enum rt_scope_t s)
2281 static char buf[32];
2283 switch (s) {
2284 case RT_SCOPE_UNIVERSE: return "universe";
2285 case RT_SCOPE_SITE: return "site";
2286 case RT_SCOPE_LINK: return "link";
2287 case RT_SCOPE_HOST: return "host";
2288 case RT_SCOPE_NOWHERE: return "nowhere";
2289 default:
2290 snprintf(buf, sizeof(buf), "scope=%d", s);
2291 return buf;
2295 static const char *rtn_type_names[__RTN_MAX] = {
2296 [RTN_UNSPEC] = "UNSPEC",
2297 [RTN_UNICAST] = "UNICAST",
2298 [RTN_LOCAL] = "LOCAL",
2299 [RTN_BROADCAST] = "BROADCAST",
2300 [RTN_ANYCAST] = "ANYCAST",
2301 [RTN_MULTICAST] = "MULTICAST",
2302 [RTN_BLACKHOLE] = "BLACKHOLE",
2303 [RTN_UNREACHABLE] = "UNREACHABLE",
2304 [RTN_PROHIBIT] = "PROHIBIT",
2305 [RTN_THROW] = "THROW",
2306 [RTN_NAT] = "NAT",
2307 [RTN_XRESOLVE] = "XRESOLVE",
2310 static inline const char *rtn_type(unsigned t)
2312 static char buf[32];
2314 if (t < __RTN_MAX && rtn_type_names[t])
2315 return rtn_type_names[t];
2316 snprintf(buf, sizeof(buf), "type %d", t);
2317 return buf;
2320 /* Pretty print the trie */
2321 static int fib_trie_seq_show(struct seq_file *seq, void *v)
2323 const struct fib_trie_iter *iter = seq->private;
2324 struct node *n = v;
2326 if (v == SEQ_START_TOKEN)
2327 return 0;
2329 if (!node_parent(n)) {
2330 if (iter->trie == trie_local)
2331 seq_puts(seq, "<local>:\n");
2332 else
2333 seq_puts(seq, "<main>:\n");
2336 if (IS_TNODE(n)) {
2337 struct tnode *tn = (struct tnode *) n;
2338 __be32 prf = htonl(mask_pfx(tn->key, tn->pos));
2340 seq_indent(seq, iter->depth-1);
2341 seq_printf(seq, " +-- %d.%d.%d.%d/%d %d %d %d\n",
2342 NIPQUAD(prf), tn->pos, tn->bits, tn->full_children,
2343 tn->empty_children);
2345 } else {
2346 struct leaf *l = (struct leaf *) n;
2347 int i;
2348 __be32 val = htonl(l->key);
2350 seq_indent(seq, iter->depth);
2351 seq_printf(seq, " |-- %d.%d.%d.%d\n", NIPQUAD(val));
2352 for (i = 32; i >= 0; i--) {
2353 struct leaf_info *li = find_leaf_info(l, i);
2354 if (li) {
2355 struct fib_alias *fa;
2356 list_for_each_entry_rcu(fa, &li->falh, fa_list) {
2357 seq_indent(seq, iter->depth+1);
2358 seq_printf(seq, " /%d %s %s", i,
2359 rtn_scope(fa->fa_scope),
2360 rtn_type(fa->fa_type));
2361 if (fa->fa_tos)
2362 seq_printf(seq, "tos =%d\n",
2363 fa->fa_tos);
2364 seq_putc(seq, '\n');
2370 return 0;
2373 static const struct seq_operations fib_trie_seq_ops = {
2374 .start = fib_trie_seq_start,
2375 .next = fib_trie_seq_next,
2376 .stop = fib_trie_seq_stop,
2377 .show = fib_trie_seq_show,
2380 static int fib_trie_seq_open(struct inode *inode, struct file *file)
2382 return seq_open_private(file, &fib_trie_seq_ops,
2383 sizeof(struct fib_trie_iter));
2386 static const struct file_operations fib_trie_fops = {
2387 .owner = THIS_MODULE,
2388 .open = fib_trie_seq_open,
2389 .read = seq_read,
2390 .llseek = seq_lseek,
2391 .release = seq_release_private,
2394 static unsigned fib_flag_trans(int type, __be32 mask, const struct fib_info *fi)
2396 static unsigned type2flags[RTN_MAX + 1] = {
2397 [7] = RTF_REJECT, [8] = RTF_REJECT,
2399 unsigned flags = type2flags[type];
2401 if (fi && fi->fib_nh->nh_gw)
2402 flags |= RTF_GATEWAY;
2403 if (mask == htonl(0xFFFFFFFF))
2404 flags |= RTF_HOST;
2405 flags |= RTF_UP;
2406 return flags;
2410 * This outputs /proc/net/route.
2411 * The format of the file is not supposed to be changed
2412 * and needs to be same as fib_hash output to avoid breaking
2413 * legacy utilities
2415 static int fib_route_seq_show(struct seq_file *seq, void *v)
2417 const struct fib_trie_iter *iter = seq->private;
2418 struct leaf *l = v;
2419 int i;
2420 char bf[128];
2422 if (v == SEQ_START_TOKEN) {
2423 seq_printf(seq, "%-127s\n", "Iface\tDestination\tGateway "
2424 "\tFlags\tRefCnt\tUse\tMetric\tMask\t\tMTU"
2425 "\tWindow\tIRTT");
2426 return 0;
2429 if (iter->trie == trie_local)
2430 return 0;
2431 if (IS_TNODE(l))
2432 return 0;
2434 for (i=32; i>=0; i--) {
2435 struct leaf_info *li = find_leaf_info(l, i);
2436 struct fib_alias *fa;
2437 __be32 mask, prefix;
2439 if (!li)
2440 continue;
2442 mask = inet_make_mask(li->plen);
2443 prefix = htonl(l->key);
2445 list_for_each_entry_rcu(fa, &li->falh, fa_list) {
2446 const struct fib_info *fi = fa->fa_info;
2447 unsigned flags = fib_flag_trans(fa->fa_type, mask, fi);
2449 if (fa->fa_type == RTN_BROADCAST
2450 || fa->fa_type == RTN_MULTICAST)
2451 continue;
2453 if (fi)
2454 snprintf(bf, sizeof(bf),
2455 "%s\t%08X\t%08X\t%04X\t%d\t%u\t%d\t%08X\t%d\t%u\t%u",
2456 fi->fib_dev ? fi->fib_dev->name : "*",
2457 prefix,
2458 fi->fib_nh->nh_gw, flags, 0, 0,
2459 fi->fib_priority,
2460 mask,
2461 (fi->fib_advmss ? fi->fib_advmss + 40 : 0),
2462 fi->fib_window,
2463 fi->fib_rtt >> 3);
2464 else
2465 snprintf(bf, sizeof(bf),
2466 "*\t%08X\t%08X\t%04X\t%d\t%u\t%d\t%08X\t%d\t%u\t%u",
2467 prefix, 0, flags, 0, 0, 0,
2468 mask, 0, 0, 0);
2470 seq_printf(seq, "%-127s\n", bf);
2474 return 0;
2477 static const struct seq_operations fib_route_seq_ops = {
2478 .start = fib_trie_seq_start,
2479 .next = fib_trie_seq_next,
2480 .stop = fib_trie_seq_stop,
2481 .show = fib_route_seq_show,
2484 static int fib_route_seq_open(struct inode *inode, struct file *file)
2486 return seq_open_private(file, &fib_route_seq_ops,
2487 sizeof(struct fib_trie_iter));
2490 static const struct file_operations fib_route_fops = {
2491 .owner = THIS_MODULE,
2492 .open = fib_route_seq_open,
2493 .read = seq_read,
2494 .llseek = seq_lseek,
2495 .release = seq_release_private,
2498 int __init fib_proc_init(void)
2500 if (!proc_net_fops_create(&init_net, "fib_trie", S_IRUGO, &fib_trie_fops))
2501 goto out1;
2503 if (!proc_net_fops_create(&init_net, "fib_triestat", S_IRUGO, &fib_triestat_fops))
2504 goto out2;
2506 if (!proc_net_fops_create(&init_net, "route", S_IRUGO, &fib_route_fops))
2507 goto out3;
2509 return 0;
2511 out3:
2512 proc_net_remove(&init_net, "fib_triestat");
2513 out2:
2514 proc_net_remove(&init_net, "fib_trie");
2515 out1:
2516 return -ENOMEM;
2519 void __init fib_proc_exit(void)
2521 proc_net_remove(&init_net, "fib_trie");
2522 proc_net_remove(&init_net, "fib_triestat");
2523 proc_net_remove(&init_net, "route");
2526 #endif /* CONFIG_PROC_FS */