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[PATCH] mark struct file_operations const 7
[linux-2.6/linux-acpi-2.6/ibm-acpi-2.6.git] / net / ipv4 / fib_trie.c
blobc33dca073801b86e6b851caf88f8ec838900a532
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.
6 *
7 * Robert Olsson <robert.olsson@its.uu.se> Uppsala Universitet
8 * & Swedish University of Agricultural Sciences.
9 *
10 * Jens Laas <jens.laas@data.slu.se> Swedish University of
11 * Agricultural Sciences.
12 *
13 * Hans Liss <hans.liss@its.uu.se> Uppsala Universitet
14 *
15 * This work is based on the LPC-trie which is originally descibed in:
16 *
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/
20 *
21 *
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
24 *
25 * Version: $Id: fib_trie.c,v 1.3 2005/06/08 14:20:01 robert Exp $
26 *
27 *
28 * Code from fib_hash has been reused which includes the following header:
29 *
30 *
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.
34 *
35 * IPv4 FIB: lookup engine and maintenance routines.
36 *
37 *
38 * Authors: Alexey Kuznetsov, <kuznet@ms2.inr.ac.ru>
39 *
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.
44 *
45 * Substantial contributions to this work comes from:
46 *
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>
51 */
52
53 #define VERSION "0.407"
54
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/sched.h>
61 #include <linux/mm.h>
62 #include <linux/string.h>
63 #include <linux/socket.h>
64 #include <linux/sockios.h>
65 #include <linux/errno.h>
66 #include <linux/in.h>
67 #include <linux/inet.h>
68 #include <linux/inetdevice.h>
69 #include <linux/netdevice.h>
70 #include <linux/if_arp.h>
71 #include <linux/proc_fs.h>
72 #include <linux/rcupdate.h>
73 #include <linux/skbuff.h>
74 #include <linux/netlink.h>
75 #include <linux/init.h>
76 #include <linux/list.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"
84
85 #undef CONFIG_IP_FIB_TRIE_STATS
86 #define MAX_STAT_DEPTH 32
87
88 #define KEYLENGTH (8*sizeof(t_key))
89 #define MASK_PFX(k, l) (((l)==0)?0:(k >> (KEYLENGTH-l)) << (KEYLENGTH-l))
90 #define TKEY_GET_MASK(offset, bits) (((bits)==0)?0:((t_key)(-1) << (KEYLENGTH - bits) >> offset))
91
92 typedef unsigned int t_key;
93
94 #define T_TNODE 0
95 #define T_LEAF 1
96 #define NODE_TYPE_MASK 0x1UL
97 #define NODE_PARENT(node) \
98 ((struct tnode *)rcu_dereference(((node)->parent & ~NODE_TYPE_MASK)))
99
100 #define NODE_TYPE(node) ((node)->parent & NODE_TYPE_MASK)
101
102 #define NODE_SET_PARENT(node, ptr) \
103 rcu_assign_pointer((node)->parent, \
104 ((unsigned long)(ptr)) | NODE_TYPE(node))
105
106 #define IS_TNODE(n) (!(n->parent & T_LEAF))
107 #define IS_LEAF(n) (n->parent & T_LEAF)
108
109 struct node {
110 t_key key;
111 unsigned long parent;
112 };
113
114 struct leaf {
115 t_key key;
116 unsigned long parent;
117 struct hlist_head list;
118 struct rcu_head rcu;
119 };
120
121 struct leaf_info {
122 struct hlist_node hlist;
123 struct rcu_head rcu;
124 int plen;
125 struct list_head falh;
126 };
127
128 struct tnode {
129 t_key key;
130 unsigned long parent;
131 unsigned short pos:5; /* 2log(KEYLENGTH) bits needed */
132 unsigned short bits:5; /* 2log(KEYLENGTH) bits needed */
133 unsigned short full_children; /* KEYLENGTH bits needed */
134 unsigned short empty_children; /* KEYLENGTH bits needed */
135 struct rcu_head rcu;
136 struct node *child[0];
137 };
138
139 #ifdef CONFIG_IP_FIB_TRIE_STATS
140 struct trie_use_stats {
141 unsigned int gets;
142 unsigned int backtrack;
143 unsigned int semantic_match_passed;
144 unsigned int semantic_match_miss;
145 unsigned int null_node_hit;
146 unsigned int resize_node_skipped;
147 };
148 #endif
149
150 struct trie_stat {
151 unsigned int totdepth;
152 unsigned int maxdepth;
153 unsigned int tnodes;
154 unsigned int leaves;
155 unsigned int nullpointers;
156 unsigned int nodesizes[MAX_STAT_DEPTH];
157 };
158
159 struct trie {
160 struct node *trie;
161 #ifdef CONFIG_IP_FIB_TRIE_STATS
162 struct trie_use_stats stats;
163 #endif
164 int size;
165 unsigned int revision;
166 };
167
168 static void put_child(struct trie *t, struct tnode *tn, int i, struct node *n);
169 static void tnode_put_child_reorg(struct tnode *tn, int i, struct node *n, int wasfull);
170 static struct node *resize(struct trie *t, struct tnode *tn);
171 static struct tnode *inflate(struct trie *t, struct tnode *tn);
172 static struct tnode *halve(struct trie *t, struct tnode *tn);
173 static void tnode_free(struct tnode *tn);
174
175 static struct kmem_cache *fn_alias_kmem __read_mostly;
176 static struct trie *trie_local = NULL, *trie_main = NULL;
177
178
179 /* rcu_read_lock needs to be hold by caller from readside */
180
181 static inline struct node *tnode_get_child(struct tnode *tn, int i)
182 {
183 BUG_ON(i >= 1 << tn->bits);
184
185 return rcu_dereference(tn->child[i]);
186 }
187
188 static inline int tnode_child_length(const struct tnode *tn)
189 {
190 return 1 << tn->bits;
191 }
192
193 static inline t_key tkey_extract_bits(t_key a, int offset, int bits)
194 {
195 if (offset < KEYLENGTH)
196 return ((t_key)(a << offset)) >> (KEYLENGTH - bits);
197 else
198 return 0;
199 }
200
201 static inline int tkey_equals(t_key a, t_key b)
202 {
203 return a == b;
204 }
205
206 static inline int tkey_sub_equals(t_key a, int offset, int bits, t_key b)
207 {
208 if (bits == 0 || offset >= KEYLENGTH)
209 return 1;
210 bits = bits > KEYLENGTH ? KEYLENGTH : bits;
211 return ((a ^ b) << offset) >> (KEYLENGTH - bits) == 0;
212 }
213
214 static inline int tkey_mismatch(t_key a, int offset, t_key b)
215 {
216 t_key diff = a ^ b;
217 int i = offset;
218
219 if (!diff)
220 return 0;
221 while ((diff << i) >> (KEYLENGTH-1) == 0)
222 i++;
223 return i;
224 }
225
226 /*
227 To understand this stuff, an understanding of keys and all their bits is
228 necessary. Every node in the trie has a key associated with it, but not
229 all of the bits in that key are significant.
230
231 Consider a node 'n' and its parent 'tp'.
232
233 If n is a leaf, every bit in its key is significant. Its presence is
234 necessitated by path compression, since during a tree traversal (when
235 searching for a leaf - unless we are doing an insertion) we will completely
236 ignore all skipped bits we encounter. Thus we need to verify, at the end of
237 a potentially successful search, that we have indeed been walking the
238 correct key path.
239
240 Note that we can never "miss" the correct key in the tree if present by
241 following the wrong path. Path compression ensures that segments of the key
242 that are the same for all keys with a given prefix are skipped, but the
243 skipped part *is* identical for each node in the subtrie below the skipped
244 bit! trie_insert() in this implementation takes care of that - note the
245 call to tkey_sub_equals() in trie_insert().
246
247 if n is an internal node - a 'tnode' here, the various parts of its key
248 have many different meanings.
249
250 Example:
251 _________________________________________________________________
252 | i | i | i | i | i | i | i | N | N | N | S | S | S | S | S | C |
253 -----------------------------------------------------------------
254 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15
255
256 _________________________________________________________________
257 | C | C | C | u | u | u | u | u | u | u | u | u | u | u | u | u |
258 -----------------------------------------------------------------
259 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31
260
261 tp->pos = 7
262 tp->bits = 3
263 n->pos = 15
264 n->bits = 4
265
266 First, let's just ignore the bits that come before the parent tp, that is
267 the bits from 0 to (tp->pos-1). They are *known* but at this point we do
268 not use them for anything.
269
270 The bits from (tp->pos) to (tp->pos + tp->bits - 1) - "N", above - are the
271 index into the parent's child array. That is, they will be used to find
272 'n' among tp's children.
273
274 The bits from (tp->pos + tp->bits) to (n->pos - 1) - "S" - are skipped bits
275 for the node n.
276
277 All the bits we have seen so far are significant to the node n. The rest
278 of the bits are really not needed or indeed known in n->key.
279
280 The bits from (n->pos) to (n->pos + n->bits - 1) - "C" - are the index into
281 n's child array, and will of course be different for each child.
282
283
284 The rest of the bits, from (n->pos + n->bits) onward, are completely unknown
285 at this point.
286
287 */
288
289 static inline void check_tnode(const struct tnode *tn)
290 {
291 WARN_ON(tn && tn->pos+tn->bits > 32);
292 }
293
294 static int halve_threshold = 25;
295 static int inflate_threshold = 50;
296 static int halve_threshold_root = 15;
297 static int inflate_threshold_root = 25;
298
299
300 static void __alias_free_mem(struct rcu_head *head)
301 {
302 struct fib_alias *fa = container_of(head, struct fib_alias, rcu);
303 kmem_cache_free(fn_alias_kmem, fa);
304 }
305
306 static inline void alias_free_mem_rcu(struct fib_alias *fa)
307 {
308 call_rcu(&fa->rcu, __alias_free_mem);
309 }
310
311 static void __leaf_free_rcu(struct rcu_head *head)
312 {
313 kfree(container_of(head, struct leaf, rcu));
314 }
315
316 static void __leaf_info_free_rcu(struct rcu_head *head)
317 {
318 kfree(container_of(head, struct leaf_info, rcu));
319 }
320
321 static inline void free_leaf_info(struct leaf_info *leaf)
322 {
323 call_rcu(&leaf->rcu, __leaf_info_free_rcu);
324 }
325
326 static struct tnode *tnode_alloc(unsigned int size)
327 {
328 struct page *pages;
329
330 if (size <= PAGE_SIZE)
331 return kcalloc(size, 1, GFP_KERNEL);
332
333 pages = alloc_pages(GFP_KERNEL|__GFP_ZERO, get_order(size));
334 if (!pages)
335 return NULL;
336
337 return page_address(pages);
338 }
339
340 static void __tnode_free_rcu(struct rcu_head *head)
341 {
342 struct tnode *tn = container_of(head, struct tnode, rcu);
343 unsigned int size = sizeof(struct tnode) +
344 (1 << tn->bits) * sizeof(struct node *);
345
346 if (size <= PAGE_SIZE)
347 kfree(tn);
348 else
349 free_pages((unsigned long)tn, get_order(size));
350 }
351
352 static inline void tnode_free(struct tnode *tn)
353 {
354 if(IS_LEAF(tn)) {
355 struct leaf *l = (struct leaf *) tn;
356 call_rcu_bh(&l->rcu, __leaf_free_rcu);
357 }
358 else
359 call_rcu(&tn->rcu, __tnode_free_rcu);
360 }
361
362 static struct leaf *leaf_new(void)
363 {
364 struct leaf *l = kmalloc(sizeof(struct leaf), GFP_KERNEL);
365 if (l) {
366 l->parent = T_LEAF;
367 INIT_HLIST_HEAD(&l->list);
368 }
369 return l;
370 }
371
372 static struct leaf_info *leaf_info_new(int plen)
373 {
374 struct leaf_info *li = kmalloc(sizeof(struct leaf_info), GFP_KERNEL);
375 if (li) {
376 li->plen = plen;
377 INIT_LIST_HEAD(&li->falh);
378 }
379 return li;
380 }
381
382 static struct tnode* tnode_new(t_key key, int pos, int bits)
383 {
384 int nchildren = 1<<bits;
385 int sz = sizeof(struct tnode) + nchildren * sizeof(struct node *);
386 struct tnode *tn = tnode_alloc(sz);
387
388 if (tn) {
389 memset(tn, 0, sz);
390 tn->parent = T_TNODE;
391 tn->pos = pos;
392 tn->bits = bits;
393 tn->key = key;
394 tn->full_children = 0;
395 tn->empty_children = 1<<bits;
396 }
397
398 pr_debug("AT %p s=%u %u\n", tn, (unsigned int) sizeof(struct tnode),
399 (unsigned int) (sizeof(struct node) * 1<<bits));
400 return tn;
401 }
402
403 /*
404 * Check whether a tnode 'n' is "full", i.e. it is an internal node
405 * and no bits are skipped. See discussion in dyntree paper p. 6
406 */
407
408 static inline int tnode_full(const struct tnode *tn, const struct node *n)
409 {
410 if (n == NULL || IS_LEAF(n))
411 return 0;
412
413 return ((struct tnode *) n)->pos == tn->pos + tn->bits;
414 }
415
416 static inline void put_child(struct trie *t, struct tnode *tn, int i, struct node *n)
417 {
418 tnode_put_child_reorg(tn, i, n, -1);
419 }
420
421 /*
422 * Add a child at position i overwriting the old value.
423 * Update the value of full_children and empty_children.
424 */
425
426 static void tnode_put_child_reorg(struct tnode *tn, int i, struct node *n, int wasfull)
427 {
428 struct node *chi = tn->child[i];
429 int isfull;
430
431 BUG_ON(i >= 1<<tn->bits);
432
433
434 /* update emptyChildren */
435 if (n == NULL && chi != NULL)
436 tn->empty_children++;
437 else if (n != NULL && chi == NULL)
438 tn->empty_children--;
439
440 /* update fullChildren */
441 if (wasfull == -1)
442 wasfull = tnode_full(tn, chi);
443
444 isfull = tnode_full(tn, n);
445 if (wasfull && !isfull)
446 tn->full_children--;
447 else if (!wasfull && isfull)
448 tn->full_children++;
449
450 if (n)
451 NODE_SET_PARENT(n, tn);
452
453 rcu_assign_pointer(tn->child[i], n);
454 }
455
456 static struct node *resize(struct trie *t, struct tnode *tn)
457 {
458 int i;
459 int err = 0;
460 struct tnode *old_tn;
461 int inflate_threshold_use;
462 int halve_threshold_use;
463
464 if (!tn)
465 return NULL;
466
467 pr_debug("In tnode_resize %p inflate_threshold=%d threshold=%d\n",
468 tn, inflate_threshold, halve_threshold);
469
470 /* No children */
471 if (tn->empty_children == tnode_child_length(tn)) {
472 tnode_free(tn);
473 return NULL;
474 }
475 /* One child */
476 if (tn->empty_children == tnode_child_length(tn) - 1)
477 for (i = 0; i < tnode_child_length(tn); i++) {
478 struct node *n;
479
480 n = tn->child[i];
481 if (!n)
482 continue;
483
484 /* compress one level */
485 NODE_SET_PARENT(n, NULL);
486 tnode_free(tn);
487 return n;
488 }
489 /*
490 * Double as long as the resulting node has a number of
491 * nonempty nodes that are above the threshold.
492 */
493
494 /*
495 * From "Implementing a dynamic compressed trie" by Stefan Nilsson of
496 * the Helsinki University of Technology and Matti Tikkanen of Nokia
497 * Telecommunications, page 6:
498 * "A node is doubled if the ratio of non-empty children to all
499 * children in the *doubled* node is at least 'high'."
500 *
501 * 'high' in this instance is the variable 'inflate_threshold'. It
502 * is expressed as a percentage, so we multiply it with
503 * tnode_child_length() and instead of multiplying by 2 (since the
504 * child array will be doubled by inflate()) and multiplying
505 * the left-hand side by 100 (to handle the percentage thing) we
506 * multiply the left-hand side by 50.
507 *
508 * The left-hand side may look a bit weird: tnode_child_length(tn)
509 * - tn->empty_children is of course the number of non-null children
510 * in the current node. tn->full_children is the number of "full"
511 * children, that is non-null tnodes with a skip value of 0.
512 * All of those will be doubled in the resulting inflated tnode, so
513 * we just count them one extra time here.
514 *
515 * A clearer way to write this would be:
516 *
517 * to_be_doubled = tn->full_children;
518 * not_to_be_doubled = tnode_child_length(tn) - tn->empty_children -
519 * tn->full_children;
520 *
521 * new_child_length = tnode_child_length(tn) * 2;
522 *
523 * new_fill_factor = 100 * (not_to_be_doubled + 2*to_be_doubled) /
524 * new_child_length;
525 * if (new_fill_factor >= inflate_threshold)
526 *
527 * ...and so on, tho it would mess up the while () loop.
528 *
529 * anyway,
530 * 100 * (not_to_be_doubled + 2*to_be_doubled) / new_child_length >=
531 * inflate_threshold
532 *
533 * avoid a division:
534 * 100 * (not_to_be_doubled + 2*to_be_doubled) >=
535 * inflate_threshold * new_child_length
536 *
537 * expand not_to_be_doubled and to_be_doubled, and shorten:
538 * 100 * (tnode_child_length(tn) - tn->empty_children +
539 * tn->full_children) >= inflate_threshold * new_child_length
540 *
541 * expand new_child_length:
542 * 100 * (tnode_child_length(tn) - tn->empty_children +
543 * tn->full_children) >=
544 * inflate_threshold * tnode_child_length(tn) * 2
545 *
546 * shorten again:
547 * 50 * (tn->full_children + tnode_child_length(tn) -
548 * tn->empty_children) >= inflate_threshold *
549 * tnode_child_length(tn)
550 *
551 */
552
553 check_tnode(tn);
554
555 /* Keep root node larger */
556
557 if(!tn->parent)
558 inflate_threshold_use = inflate_threshold_root;
559 else
560 inflate_threshold_use = inflate_threshold;
561
562 err = 0;
563 while ((tn->full_children > 0 &&
564 50 * (tn->full_children + tnode_child_length(tn) - tn->empty_children) >=
565 inflate_threshold_use * tnode_child_length(tn))) {
566
567 old_tn = tn;
568 tn = inflate(t, tn);
569 if (IS_ERR(tn)) {
570 tn = old_tn;
571 #ifdef CONFIG_IP_FIB_TRIE_STATS
572 t->stats.resize_node_skipped++;
573 #endif
574 break;
575 }
576 }
577
578 check_tnode(tn);
579
580 /*
581 * Halve as long as the number of empty children in this
582 * node is above threshold.
583 */
584
585
586 /* Keep root node larger */
587
588 if(!tn->parent)
589 halve_threshold_use = halve_threshold_root;
590 else
591 halve_threshold_use = halve_threshold;
592
593 err = 0;
594 while (tn->bits > 1 &&
595 100 * (tnode_child_length(tn) - tn->empty_children) <
596 halve_threshold_use * tnode_child_length(tn)) {
597
598 old_tn = tn;
599 tn = halve(t, tn);
600 if (IS_ERR(tn)) {
601 tn = old_tn;
602 #ifdef CONFIG_IP_FIB_TRIE_STATS
603 t->stats.resize_node_skipped++;
604 #endif
605 break;
606 }
607 }
608
609
610 /* Only one child remains */
611 if (tn->empty_children == tnode_child_length(tn) - 1)
612 for (i = 0; i < tnode_child_length(tn); i++) {
613 struct node *n;
614
615 n = tn->child[i];
616 if (!n)
617 continue;
618
619 /* compress one level */
620
621 NODE_SET_PARENT(n, NULL);
622 tnode_free(tn);
623 return n;
624 }
625
626 return (struct node *) tn;
627 }
628
629 static struct tnode *inflate(struct trie *t, struct tnode *tn)
630 {
631 struct tnode *inode;
632 struct tnode *oldtnode = tn;
633 int olen = tnode_child_length(tn);
634 int i;
635
636 pr_debug("In inflate\n");
637
638 tn = tnode_new(oldtnode->key, oldtnode->pos, oldtnode->bits + 1);
639
640 if (!tn)
641 return ERR_PTR(-ENOMEM);
642
643 /*
644 * Preallocate and store tnodes before the actual work so we
645 * don't get into an inconsistent state if memory allocation
646 * fails. In case of failure we return the oldnode and inflate
647 * of tnode is ignored.
648 */
649
650 for (i = 0; i < olen; i++) {
651 struct tnode *inode = (struct tnode *) tnode_get_child(oldtnode, i);
652
653 if (inode &&
654 IS_TNODE(inode) &&
655 inode->pos == oldtnode->pos + oldtnode->bits &&
656 inode->bits > 1) {
657 struct tnode *left, *right;
658 t_key m = TKEY_GET_MASK(inode->pos, 1);
659
660 left = tnode_new(inode->key&(~m), inode->pos + 1,
661 inode->bits - 1);
662 if (!left)
663 goto nomem;
664
665 right = tnode_new(inode->key|m, inode->pos + 1,
666 inode->bits - 1);
667
668 if (!right) {
669 tnode_free(left);
670 goto nomem;
671 }
672
673 put_child(t, tn, 2*i, (struct node *) left);
674 put_child(t, tn, 2*i+1, (struct node *) right);
675 }
676 }
677
678 for (i = 0; i < olen; i++) {
679 struct node *node = tnode_get_child(oldtnode, i);
680 struct tnode *left, *right;
681 int size, j;
682
683 /* An empty child */
684 if (node == NULL)
685 continue;
686
687 /* A leaf or an internal node with skipped bits */
688
689 if (IS_LEAF(node) || ((struct tnode *) node)->pos >
690 tn->pos + tn->bits - 1) {
691 if (tkey_extract_bits(node->key, oldtnode->pos + oldtnode->bits,
692 1) == 0)
693 put_child(t, tn, 2*i, node);
694 else
695 put_child(t, tn, 2*i+1, node);
696 continue;
697 }
698
699 /* An internal node with two children */
700 inode = (struct tnode *) node;
701
702 if (inode->bits == 1) {
703 put_child(t, tn, 2*i, inode->child[0]);
704 put_child(t, tn, 2*i+1, inode->child[1]);
705
706 tnode_free(inode);
707 continue;
708 }
709
710 /* An internal node with more than two children */
711
712 /* We will replace this node 'inode' with two new
713 * ones, 'left' and 'right', each with half of the
714 * original children. The two new nodes will have
715 * a position one bit further down the key and this
716 * means that the "significant" part of their keys
717 * (see the discussion near the top of this file)
718 * will differ by one bit, which will be "0" in
719 * left's key and "1" in right's key. Since we are
720 * moving the key position by one step, the bit that
721 * we are moving away from - the bit at position
722 * (inode->pos) - is the one that will differ between
723 * left and right. So... we synthesize that bit in the
724 * two new keys.
725 * The mask 'm' below will be a single "one" bit at
726 * the position (inode->pos)
727 */
728
729 /* Use the old key, but set the new significant
730 * bit to zero.
731 */
732
733 left = (struct tnode *) tnode_get_child(tn, 2*i);
734 put_child(t, tn, 2*i, NULL);
735
736 BUG_ON(!left);
737
738 right = (struct tnode *) tnode_get_child(tn, 2*i+1);
739 put_child(t, tn, 2*i+1, NULL);
740
741 BUG_ON(!right);
742
743 size = tnode_child_length(left);
744 for (j = 0; j < size; j++) {
745 put_child(t, left, j, inode->child[j]);
746 put_child(t, right, j, inode->child[j + size]);
747 }
748 put_child(t, tn, 2*i, resize(t, left));
749 put_child(t, tn, 2*i+1, resize(t, right));
750
751 tnode_free(inode);
752 }
753 tnode_free(oldtnode);
754 return tn;
755 nomem:
756 {
757 int size = tnode_child_length(tn);
758 int j;
759
760 for (j = 0; j < size; j++)
761 if (tn->child[j])
762 tnode_free((struct tnode *)tn->child[j]);
763
764 tnode_free(tn);
765
766 return ERR_PTR(-ENOMEM);
767 }
768 }
769
770 static struct tnode *halve(struct trie *t, struct tnode *tn)
771 {
772 struct tnode *oldtnode = tn;
773 struct node *left, *right;
774 int i;
775 int olen = tnode_child_length(tn);
776
777 pr_debug("In halve\n");
778
779 tn = tnode_new(oldtnode->key, oldtnode->pos, oldtnode->bits - 1);
780
781 if (!tn)
782 return ERR_PTR(-ENOMEM);
783
784 /*
785 * Preallocate and store tnodes before the actual work so we
786 * don't get into an inconsistent state if memory allocation
787 * fails. In case of failure we return the oldnode and halve
788 * of tnode is ignored.
789 */
790
791 for (i = 0; i < olen; i += 2) {
792 left = tnode_get_child(oldtnode, i);
793 right = tnode_get_child(oldtnode, i+1);
794
795 /* Two nonempty children */
796 if (left && right) {
797 struct tnode *newn;
798
799 newn = tnode_new(left->key, tn->pos + tn->bits, 1);
800
801 if (!newn)
802 goto nomem;
803
804 put_child(t, tn, i/2, (struct node *)newn);
805 }
806
807 }
808
809 for (i = 0; i < olen; i += 2) {
810 struct tnode *newBinNode;
811
812 left = tnode_get_child(oldtnode, i);
813 right = tnode_get_child(oldtnode, i+1);
814
815 /* At least one of the children is empty */
816 if (left == NULL) {
817 if (right == NULL) /* Both are empty */
818 continue;
819 put_child(t, tn, i/2, right);
820 continue;
821 }
822
823 if (right == NULL) {
824 put_child(t, tn, i/2, left);
825 continue;
826 }
827
828 /* Two nonempty children */
829 newBinNode = (struct tnode *) tnode_get_child(tn, i/2);
830 put_child(t, tn, i/2, NULL);
831 put_child(t, newBinNode, 0, left);
832 put_child(t, newBinNode, 1, right);
833 put_child(t, tn, i/2, resize(t, newBinNode));
834 }
835 tnode_free(oldtnode);
836 return tn;
837 nomem:
838 {
839 int size = tnode_child_length(tn);
840 int j;
841
842 for (j = 0; j < size; j++)
843 if (tn->child[j])
844 tnode_free((struct tnode *)tn->child[j]);
845
846 tnode_free(tn);
847
848 return ERR_PTR(-ENOMEM);
849 }
850 }
851
852 static void trie_init(struct trie *t)
853 {
854 if (!t)
855 return;
856
857 t->size = 0;
858 rcu_assign_pointer(t->trie, NULL);
859 t->revision = 0;
860 #ifdef CONFIG_IP_FIB_TRIE_STATS
861 memset(&t->stats, 0, sizeof(struct trie_use_stats));
862 #endif
863 }
864
865 /* readside must use rcu_read_lock currently dump routines
866 via get_fa_head and dump */
867
868 static struct leaf_info *find_leaf_info(struct leaf *l, int plen)
869 {
870 struct hlist_head *head = &l->list;
871 struct hlist_node *node;
872 struct leaf_info *li;
873
874 hlist_for_each_entry_rcu(li, node, head, hlist)
875 if (li->plen == plen)
876 return li;
877
878 return NULL;
879 }
880
881 static inline struct list_head * get_fa_head(struct leaf *l, int plen)
882 {
883 struct leaf_info *li = find_leaf_info(l, plen);
884
885 if (!li)
886 return NULL;
887
888 return &li->falh;
889 }
890
891 static void insert_leaf_info(struct hlist_head *head, struct leaf_info *new)
892 {
893 struct leaf_info *li = NULL, *last = NULL;
894 struct hlist_node *node;
895
896 if (hlist_empty(head)) {
897 hlist_add_head_rcu(&new->hlist, head);
898 } else {
899 hlist_for_each_entry(li, node, head, hlist) {
900 if (new->plen > li->plen)
901 break;
902
903 last = li;
904 }
905 if (last)
906 hlist_add_after_rcu(&last->hlist, &new->hlist);
907 else
908 hlist_add_before_rcu(&new->hlist, &li->hlist);
909 }
910 }
911
912 /* rcu_read_lock needs to be hold by caller from readside */
913
914 static struct leaf *
915 fib_find_node(struct trie *t, u32 key)
916 {
917 int pos;
918 struct tnode *tn;
919 struct node *n;
920
921 pos = 0;
922 n = rcu_dereference(t->trie);
923
924 while (n != NULL && NODE_TYPE(n) == T_TNODE) {
925 tn = (struct tnode *) n;
926
927 check_tnode(tn);
928
929 if (tkey_sub_equals(tn->key, pos, tn->pos-pos, key)) {
930 pos = tn->pos + tn->bits;
931 n = tnode_get_child(tn, tkey_extract_bits(key, tn->pos, tn->bits));
932 } else
933 break;
934 }
935 /* Case we have found a leaf. Compare prefixes */
936
937 if (n != NULL && IS_LEAF(n) && tkey_equals(key, n->key))
938 return (struct leaf *)n;
939
940 return NULL;
941 }
942
943 static struct node *trie_rebalance(struct trie *t, struct tnode *tn)
944 {
945 int wasfull;
946 t_key cindex, key;
947 struct tnode *tp = NULL;
948
949 key = tn->key;
950
951 while (tn != NULL && NODE_PARENT(tn) != NULL) {
952
953 tp = NODE_PARENT(tn);
954 cindex = tkey_extract_bits(key, tp->pos, tp->bits);
955 wasfull = tnode_full(tp, tnode_get_child(tp, cindex));
956 tn = (struct tnode *) resize (t, (struct tnode *)tn);
957 tnode_put_child_reorg((struct tnode *)tp, cindex,(struct node*)tn, wasfull);
958
959 if (!NODE_PARENT(tn))
960 break;
961
962 tn = NODE_PARENT(tn);
963 }
964 /* Handle last (top) tnode */
965 if (IS_TNODE(tn))
966 tn = (struct tnode*) resize(t, (struct tnode *)tn);
967
968 return (struct node*) tn;
969 }
970
971 /* only used from updater-side */
972
973 static struct list_head *
974 fib_insert_node(struct trie *t, int *err, u32 key, int plen)
975 {
976 int pos, newpos;
977 struct tnode *tp = NULL, *tn = NULL;
978 struct node *n;
979 struct leaf *l;
980 int missbit;
981 struct list_head *fa_head = NULL;
982 struct leaf_info *li;
983 t_key cindex;
984
985 pos = 0;
986 n = t->trie;
987
988 /* If we point to NULL, stop. Either the tree is empty and we should
989 * just put a new leaf in if, or we have reached an empty child slot,
990 * and we should just put our new leaf in that.
991 * If we point to a T_TNODE, check if it matches our key. Note that
992 * a T_TNODE might be skipping any number of bits - its 'pos' need
993 * not be the parent's 'pos'+'bits'!
994 *
995 * If it does match the current key, get pos/bits from it, extract
996 * the index from our key, push the T_TNODE and walk the tree.
997 *
998 * If it doesn't, we have to replace it with a new T_TNODE.
999 *
1000 * If we point to a T_LEAF, it might or might not have the same key
1001 * as we do. If it does, just change the value, update the T_LEAF's
1002 * value, and return it.
1003 * If it doesn't, we need to replace it with a T_TNODE.
1004 */
1005
1006 while (n != NULL && NODE_TYPE(n) == T_TNODE) {
1007 tn = (struct tnode *) n;
1008
1009 check_tnode(tn);
1010
1011 if (tkey_sub_equals(tn->key, pos, tn->pos-pos, key)) {
1012 tp = tn;
1013 pos = tn->pos + tn->bits;
1014 n = tnode_get_child(tn, tkey_extract_bits(key, tn->pos, tn->bits));
1015
1016 BUG_ON(n && NODE_PARENT(n) != tn);
1017 } else
1018 break;
1019 }
1020
1021 /*
1022 * n ----> NULL, LEAF or TNODE
1023 *
1024 * tp is n's (parent) ----> NULL or TNODE
1025 */
1026
1027 BUG_ON(tp && IS_LEAF(tp));
1028
1029 /* Case 1: n is a leaf. Compare prefixes */
1030
1031 if (n != NULL && IS_LEAF(n) && tkey_equals(key, n->key)) {
1032 struct leaf *l = (struct leaf *) n;
1033
1034 li = leaf_info_new(plen);
1035
1036 if (!li) {
1037 *err = -ENOMEM;
1038 goto err;
1039 }
1040
1041 fa_head = &li->falh;
1042 insert_leaf_info(&l->list, li);
1043 goto done;
1044 }
1045 t->size++;
1046 l = leaf_new();
1047
1048 if (!l) {
1049 *err = -ENOMEM;
1050 goto err;
1051 }
1052
1053 l->key = key;
1054 li = leaf_info_new(plen);
1055
1056 if (!li) {
1057 tnode_free((struct tnode *) l);
1058 *err = -ENOMEM;
1059 goto err;
1060 }
1061
1062 fa_head = &li->falh;
1063 insert_leaf_info(&l->list, li);
1064
1065 if (t->trie && n == NULL) {
1066 /* Case 2: n is NULL, and will just insert a new leaf */
1067
1068 NODE_SET_PARENT(l, tp);
1069
1070 cindex = tkey_extract_bits(key, tp->pos, tp->bits);
1071 put_child(t, (struct tnode *)tp, cindex, (struct node *)l);
1072 } else {
1073 /* Case 3: n is a LEAF or a TNODE and the key doesn't match. */
1074 /*
1075 * Add a new tnode here
1076 * first tnode need some special handling
1077 */
1078
1079 if (tp)
1080 pos = tp->pos+tp->bits;
1081 else
1082 pos = 0;
1083
1084 if (n) {
1085 newpos = tkey_mismatch(key, pos, n->key);
1086 tn = tnode_new(n->key, newpos, 1);
1087 } else {
1088 newpos = 0;
1089 tn = tnode_new(key, newpos, 1); /* First tnode */
1090 }
1091
1092 if (!tn) {
1093 free_leaf_info(li);
1094 tnode_free((struct tnode *) l);
1095 *err = -ENOMEM;
1096 goto err;
1097 }
1098
1099 NODE_SET_PARENT(tn, tp);
1100
1101 missbit = tkey_extract_bits(key, newpos, 1);
1102 put_child(t, tn, missbit, (struct node *)l);
1103 put_child(t, tn, 1-missbit, n);
1104
1105 if (tp) {
1106 cindex = tkey_extract_bits(key, tp->pos, tp->bits);
1107 put_child(t, (struct tnode *)tp, cindex, (struct node *)tn);
1108 } else {
1109 rcu_assign_pointer(t->trie, (struct node *)tn); /* First tnode */
1110 tp = tn;
1111 }
1112 }
1113
1114 if (tp && tp->pos + tp->bits > 32)
1115 printk(KERN_WARNING "fib_trie tp=%p pos=%d, bits=%d, key=%0x plen=%d\n",
1116 tp, tp->pos, tp->bits, key, plen);
1117
1118 /* Rebalance the trie */
1119
1120 rcu_assign_pointer(t->trie, trie_rebalance(t, tp));
1121 done:
1122 t->revision++;
1123 err:
1124 return fa_head;
1125 }
1126
1127 static int fn_trie_insert(struct fib_table *tb, struct fib_config *cfg)
1128 {
1129 struct trie *t = (struct trie *) tb->tb_data;
1130 struct fib_alias *fa, *new_fa;
1131 struct list_head *fa_head = NULL;
1132 struct fib_info *fi;
1133 int plen = cfg->fc_dst_len;
1134 u8 tos = cfg->fc_tos;
1135 u32 key, mask;
1136 int err;
1137 struct leaf *l;
1138
1139 if (plen > 32)
1140 return -EINVAL;
1141
1142 key = ntohl(cfg->fc_dst);
1143
1144 pr_debug("Insert table=%u %08x/%d\n", tb->tb_id, key, plen);
1145
1146 mask = ntohl(inet_make_mask(plen));
1147
1148 if (key & ~mask)
1149 return -EINVAL;
1150
1151 key = key & mask;
1152
1153 fi = fib_create_info(cfg);
1154 if (IS_ERR(fi)) {
1155 err = PTR_ERR(fi);
1156 goto err;
1157 }
1158
1159 l = fib_find_node(t, key);
1160 fa = NULL;
1161
1162 if (l) {
1163 fa_head = get_fa_head(l, plen);
1164 fa = fib_find_alias(fa_head, tos, fi->fib_priority);
1165 }
1166
1167 /* Now fa, if non-NULL, points to the first fib alias
1168 * with the same keys [prefix,tos,priority], if such key already
1169 * exists or to the node before which we will insert new one.
1170 *
1171 * If fa is NULL, we will need to allocate a new one and
1172 * insert to the head of f.
1173 *
1174 * If f is NULL, no fib node matched the destination key
1175 * and we need to allocate a new one of those as well.
1176 */
1177
1178 if (fa && fa->fa_info->fib_priority == fi->fib_priority) {
1179 struct fib_alias *fa_orig;
1180
1181 err = -EEXIST;
1182 if (cfg->fc_nlflags & NLM_F_EXCL)
1183 goto out;
1184
1185 if (cfg->fc_nlflags & NLM_F_REPLACE) {
1186 struct fib_info *fi_drop;
1187 u8 state;
1188
1189 err = -ENOBUFS;
1190 new_fa = kmem_cache_alloc(fn_alias_kmem, GFP_KERNEL);
1191 if (new_fa == NULL)
1192 goto out;
1193
1194 fi_drop = fa->fa_info;
1195 new_fa->fa_tos = fa->fa_tos;
1196 new_fa->fa_info = fi;
1197 new_fa->fa_type = cfg->fc_type;
1198 new_fa->fa_scope = cfg->fc_scope;
1199 state = fa->fa_state;
1200 new_fa->fa_state &= ~FA_S_ACCESSED;
1201
1202 list_replace_rcu(&fa->fa_list, &new_fa->fa_list);
1203 alias_free_mem_rcu(fa);
1204
1205 fib_release_info(fi_drop);
1206 if (state & FA_S_ACCESSED)
1207 rt_cache_flush(-1);
1208
1209 goto succeeded;
1210 }
1211 /* Error if we find a perfect match which
1212 * uses the same scope, type, and nexthop
1213 * information.
1214 */
1215 fa_orig = fa;
1216 list_for_each_entry(fa, fa_orig->fa_list.prev, fa_list) {
1217 if (fa->fa_tos != tos)
1218 break;
1219 if (fa->fa_info->fib_priority != fi->fib_priority)
1220 break;
1221 if (fa->fa_type == cfg->fc_type &&
1222 fa->fa_scope == cfg->fc_scope &&
1223 fa->fa_info == fi) {
1224 goto out;
1225 }
1226 }
1227 if (!(cfg->fc_nlflags & NLM_F_APPEND))
1228 fa = fa_orig;
1229 }
1230 err = -ENOENT;
1231 if (!(cfg->fc_nlflags & NLM_F_CREATE))
1232 goto out;
1233
1234 err = -ENOBUFS;
1235 new_fa = kmem_cache_alloc(fn_alias_kmem, GFP_KERNEL);
1236 if (new_fa == NULL)
1237 goto out;
1238
1239 new_fa->fa_info = fi;
1240 new_fa->fa_tos = tos;
1241 new_fa->fa_type = cfg->fc_type;
1242 new_fa->fa_scope = cfg->fc_scope;
1243 new_fa->fa_state = 0;
1244 /*
1245 * Insert new entry to the list.
1246 */
1247
1248 if (!fa_head) {
1249 err = 0;
1250 fa_head = fib_insert_node(t, &err, key, plen);
1251 if (err)
1252 goto out_free_new_fa;
1253 }
1254
1255 list_add_tail_rcu(&new_fa->fa_list,
1256 (fa ? &fa->fa_list : fa_head));
1257
1258 rt_cache_flush(-1);
1259 rtmsg_fib(RTM_NEWROUTE, htonl(key), new_fa, plen, tb->tb_id,
1260 &cfg->fc_nlinfo);
1261 succeeded:
1262 return 0;
1263
1264 out_free_new_fa:
1265 kmem_cache_free(fn_alias_kmem, new_fa);
1266 out:
1267 fib_release_info(fi);
1268 err:
1269 return err;
1270 }
1271
1272
1273 /* should be called with rcu_read_lock */
1274 static inline int check_leaf(struct trie *t, struct leaf *l,
1275 t_key key, int *plen, const struct flowi *flp,
1276 struct fib_result *res)
1277 {
1278 int err, i;
1279 __be32 mask;
1280 struct leaf_info *li;
1281 struct hlist_head *hhead = &l->list;
1282 struct hlist_node *node;
1283
1284 hlist_for_each_entry_rcu(li, node, hhead, hlist) {
1285 i = li->plen;
1286 mask = inet_make_mask(i);
1287 if (l->key != (key & ntohl(mask)))
1288 continue;
1289
1290 if ((err = fib_semantic_match(&li->falh, flp, res, htonl(l->key), mask, i)) <= 0) {
1291 *plen = i;
1292 #ifdef CONFIG_IP_FIB_TRIE_STATS
1293 t->stats.semantic_match_passed++;
1294 #endif
1295 return err;
1296 }
1297 #ifdef CONFIG_IP_FIB_TRIE_STATS
1298 t->stats.semantic_match_miss++;
1299 #endif
1300 }
1301 return 1;
1302 }
1303
1304 static int
1305 fn_trie_lookup(struct fib_table *tb, const struct flowi *flp, struct fib_result *res)
1306 {
1307 struct trie *t = (struct trie *) tb->tb_data;
1308 int plen, ret = 0;
1309 struct node *n;
1310 struct tnode *pn;
1311 int pos, bits;
1312 t_key key = ntohl(flp->fl4_dst);
1313 int chopped_off;
1314 t_key cindex = 0;
1315 int current_prefix_length = KEYLENGTH;
1316 struct tnode *cn;
1317 t_key node_prefix, key_prefix, pref_mismatch;
1318 int mp;
1319
1320 rcu_read_lock();
1321
1322 n = rcu_dereference(t->trie);
1323 if (!n)
1324 goto failed;
1325
1326 #ifdef CONFIG_IP_FIB_TRIE_STATS
1327 t->stats.gets++;
1328 #endif
1329
1330 /* Just a leaf? */
1331 if (IS_LEAF(n)) {
1332 if ((ret = check_leaf(t, (struct leaf *)n, key, &plen, flp, res)) <= 0)
1333 goto found;
1334 goto failed;
1335 }
1336 pn = (struct tnode *) n;
1337 chopped_off = 0;
1338
1339 while (pn) {
1340 pos = pn->pos;
1341 bits = pn->bits;
1342
1343 if (!chopped_off)
1344 cindex = tkey_extract_bits(MASK_PFX(key, current_prefix_length), pos, bits);
1345
1346 n = tnode_get_child(pn, cindex);
1347
1348 if (n == NULL) {
1349 #ifdef CONFIG_IP_FIB_TRIE_STATS
1350 t->stats.null_node_hit++;
1351 #endif
1352 goto backtrace;
1353 }
1354
1355 if (IS_LEAF(n)) {
1356 if ((ret = check_leaf(t, (struct leaf *)n, key, &plen, flp, res)) <= 0)
1357 goto found;
1358 else
1359 goto backtrace;
1360 }
1361
1362 #define HL_OPTIMIZE
1363 #ifdef HL_OPTIMIZE
1364 cn = (struct tnode *)n;
1365
1366 /*
1367 * It's a tnode, and we can do some extra checks here if we
1368 * like, to avoid descending into a dead-end branch.
1369 * This tnode is in the parent's child array at index
1370 * key[p_pos..p_pos+p_bits] but potentially with some bits
1371 * chopped off, so in reality the index may be just a
1372 * subprefix, padded with zero at the end.
1373 * We can also take a look at any skipped bits in this
1374 * tnode - everything up to p_pos is supposed to be ok,
1375 * and the non-chopped bits of the index (se previous
1376 * paragraph) are also guaranteed ok, but the rest is
1377 * considered unknown.
1378 *
1379 * The skipped bits are key[pos+bits..cn->pos].
1380 */
1381
1382 /* If current_prefix_length < pos+bits, we are already doing
1383 * actual prefix matching, which means everything from
1384 * pos+(bits-chopped_off) onward must be zero along some
1385 * branch of this subtree - otherwise there is *no* valid
1386 * prefix present. Here we can only check the skipped
1387 * bits. Remember, since we have already indexed into the
1388 * parent's child array, we know that the bits we chopped of
1389 * *are* zero.
1390 */
1391
1392 /* NOTA BENE: CHECKING ONLY SKIPPED BITS FOR THE NEW NODE HERE */
1393
1394 if (current_prefix_length < pos+bits) {
1395 if (tkey_extract_bits(cn->key, current_prefix_length,
1396 cn->pos - current_prefix_length) != 0 ||
1397 !(cn->child[0]))
1398 goto backtrace;
1399 }
1400
1401 /*
1402 * If chopped_off=0, the index is fully validated and we
1403 * only need to look at the skipped bits for this, the new,
1404 * tnode. What we actually want to do is to find out if
1405 * these skipped bits match our key perfectly, or if we will
1406 * have to count on finding a matching prefix further down,
1407 * because if we do, we would like to have some way of
1408 * verifying the existence of such a prefix at this point.
1409 */
1410
1411 /* The only thing we can do at this point is to verify that
1412 * any such matching prefix can indeed be a prefix to our
1413 * key, and if the bits in the node we are inspecting that
1414 * do not match our key are not ZERO, this cannot be true.
1415 * Thus, find out where there is a mismatch (before cn->pos)
1416 * and verify that all the mismatching bits are zero in the
1417 * new tnode's key.
1418 */
1419
1420 /* Note: We aren't very concerned about the piece of the key
1421 * that precede pn->pos+pn->bits, since these have already been
1422 * checked. The bits after cn->pos aren't checked since these are
1423 * by definition "unknown" at this point. Thus, what we want to
1424 * see is if we are about to enter the "prefix matching" state,
1425 * and in that case verify that the skipped bits that will prevail
1426 * throughout this subtree are zero, as they have to be if we are
1427 * to find a matching prefix.
1428 */
1429
1430 node_prefix = MASK_PFX(cn->key, cn->pos);
1431 key_prefix = MASK_PFX(key, cn->pos);
1432 pref_mismatch = key_prefix^node_prefix;
1433 mp = 0;
1434
1435 /* In short: If skipped bits in this node do not match the search
1436 * key, enter the "prefix matching" state.directly.
1437 */
1438 if (pref_mismatch) {
1439 while (!(pref_mismatch & (1<<(KEYLENGTH-1)))) {
1440 mp++;
1441 pref_mismatch = pref_mismatch <<1;
1442 }
1443 key_prefix = tkey_extract_bits(cn->key, mp, cn->pos-mp);
1444
1445 if (key_prefix != 0)
1446 goto backtrace;
1447
1448 if (current_prefix_length >= cn->pos)
1449 current_prefix_length = mp;
1450 }
1451 #endif
1452 pn = (struct tnode *)n; /* Descend */
1453 chopped_off = 0;
1454 continue;
1455
1456 backtrace:
1457 chopped_off++;
1458
1459 /* As zero don't change the child key (cindex) */
1460 while ((chopped_off <= pn->bits) && !(cindex & (1<<(chopped_off-1))))
1461 chopped_off++;
1462
1463 /* Decrease current_... with bits chopped off */
1464 if (current_prefix_length > pn->pos + pn->bits - chopped_off)
1465 current_prefix_length = pn->pos + pn->bits - chopped_off;
1466
1467 /*
1468 * Either we do the actual chop off according or if we have
1469 * chopped off all bits in this tnode walk up to our parent.
1470 */
1471
1472 if (chopped_off <= pn->bits) {
1473 cindex &= ~(1 << (chopped_off-1));
1474 } else {
1475 if (NODE_PARENT(pn) == NULL)
1476 goto failed;
1477
1478 /* Get Child's index */
1479 cindex = tkey_extract_bits(pn->key, NODE_PARENT(pn)->pos, NODE_PARENT(pn)->bits);
1480 pn = NODE_PARENT(pn);
1481 chopped_off = 0;
1482
1483 #ifdef CONFIG_IP_FIB_TRIE_STATS
1484 t->stats.backtrack++;
1485 #endif
1486 goto backtrace;
1487 }
1488 }
1489 failed:
1490 ret = 1;
1491 found:
1492 rcu_read_unlock();
1493 return ret;
1494 }
1495
1496 /* only called from updater side */
1497 static int trie_leaf_remove(struct trie *t, t_key key)
1498 {
1499 t_key cindex;
1500 struct tnode *tp = NULL;
1501 struct node *n = t->trie;
1502 struct leaf *l;
1503
1504 pr_debug("entering trie_leaf_remove(%p)\n", n);
1505
1506 /* Note that in the case skipped bits, those bits are *not* checked!
1507 * When we finish this, we will have NULL or a T_LEAF, and the
1508 * T_LEAF may or may not match our key.
1509 */
1510
1511 while (n != NULL && IS_TNODE(n)) {
1512 struct tnode *tn = (struct tnode *) n;
1513 check_tnode(tn);
1514 n = tnode_get_child(tn ,tkey_extract_bits(key, tn->pos, tn->bits));
1515
1516 BUG_ON(n && NODE_PARENT(n) != tn);
1517 }
1518 l = (struct leaf *) n;
1519
1520 if (!n || !tkey_equals(l->key, key))
1521 return 0;
1522
1523 /*
1524 * Key found.
1525 * Remove the leaf and rebalance the tree
1526 */
1527
1528 t->revision++;
1529 t->size--;
1530
1531 preempt_disable();
1532 tp = NODE_PARENT(n);
1533 tnode_free((struct tnode *) n);
1534
1535 if (tp) {
1536 cindex = tkey_extract_bits(key, tp->pos, tp->bits);
1537 put_child(t, (struct tnode *)tp, cindex, NULL);
1538 rcu_assign_pointer(t->trie, trie_rebalance(t, tp));
1539 } else
1540 rcu_assign_pointer(t->trie, NULL);
1541 preempt_enable();
1542
1543 return 1;
1544 }
1545
1546 static int fn_trie_delete(struct fib_table *tb, struct fib_config *cfg)
1547 {
1548 struct trie *t = (struct trie *) tb->tb_data;
1549 u32 key, mask;
1550 int plen = cfg->fc_dst_len;
1551 u8 tos = cfg->fc_tos;
1552 struct fib_alias *fa, *fa_to_delete;
1553 struct list_head *fa_head;
1554 struct leaf *l;
1555 struct leaf_info *li;
1556
1557 if (plen > 32)
1558 return -EINVAL;
1559
1560 key = ntohl(cfg->fc_dst);
1561 mask = ntohl(inet_make_mask(plen));
1562
1563 if (key & ~mask)
1564 return -EINVAL;
1565
1566 key = key & mask;
1567 l = fib_find_node(t, key);
1568
1569 if (!l)
1570 return -ESRCH;
1571
1572 fa_head = get_fa_head(l, plen);
1573 fa = fib_find_alias(fa_head, tos, 0);
1574
1575 if (!fa)
1576 return -ESRCH;
1577
1578 pr_debug("Deleting %08x/%d tos=%d t=%p\n", key, plen, tos, t);
1579
1580 fa_to_delete = NULL;
1581 fa_head = fa->fa_list.prev;
1582
1583 list_for_each_entry(fa, fa_head, fa_list) {
1584 struct fib_info *fi = fa->fa_info;
1585
1586 if (fa->fa_tos != tos)
1587 break;
1588
1589 if ((!cfg->fc_type || fa->fa_type == cfg->fc_type) &&
1590 (cfg->fc_scope == RT_SCOPE_NOWHERE ||
1591 fa->fa_scope == cfg->fc_scope) &&
1592 (!cfg->fc_protocol ||
1593 fi->fib_protocol == cfg->fc_protocol) &&
1594 fib_nh_match(cfg, fi) == 0) {
1595 fa_to_delete = fa;
1596 break;
1597 }
1598 }
1599
1600 if (!fa_to_delete)
1601 return -ESRCH;
1602
1603 fa = fa_to_delete;
1604 rtmsg_fib(RTM_DELROUTE, htonl(key), fa, plen, tb->tb_id,
1605 &cfg->fc_nlinfo);
1606
1607 l = fib_find_node(t, key);
1608 li = find_leaf_info(l, plen);
1609
1610 list_del_rcu(&fa->fa_list);
1611
1612 if (list_empty(fa_head)) {
1613 hlist_del_rcu(&li->hlist);
1614 free_leaf_info(li);
1615 }
1616
1617 if (hlist_empty(&l->list))
1618 trie_leaf_remove(t, key);
1619
1620 if (fa->fa_state & FA_S_ACCESSED)
1621 rt_cache_flush(-1);
1622
1623 fib_release_info(fa->fa_info);
1624 alias_free_mem_rcu(fa);
1625 return 0;
1626 }
1627
1628 static int trie_flush_list(struct trie *t, struct list_head *head)
1629 {
1630 struct fib_alias *fa, *fa_node;
1631 int found = 0;
1632
1633 list_for_each_entry_safe(fa, fa_node, head, fa_list) {
1634 struct fib_info *fi = fa->fa_info;
1635
1636 if (fi && (fi->fib_flags & RTNH_F_DEAD)) {
1637 list_del_rcu(&fa->fa_list);
1638 fib_release_info(fa->fa_info);
1639 alias_free_mem_rcu(fa);
1640 found++;
1641 }
1642 }
1643 return found;
1644 }
1645
1646 static int trie_flush_leaf(struct trie *t, struct leaf *l)
1647 {
1648 int found = 0;
1649 struct hlist_head *lih = &l->list;
1650 struct hlist_node *node, *tmp;
1651 struct leaf_info *li = NULL;
1652
1653 hlist_for_each_entry_safe(li, node, tmp, lih, hlist) {
1654 found += trie_flush_list(t, &li->falh);
1655
1656 if (list_empty(&li->falh)) {
1657 hlist_del_rcu(&li->hlist);
1658 free_leaf_info(li);
1659 }
1660 }
1661 return found;
1662 }
1663
1664 /* rcu_read_lock needs to be hold by caller from readside */
1665
1666 static struct leaf *nextleaf(struct trie *t, struct leaf *thisleaf)
1667 {
1668 struct node *c = (struct node *) thisleaf;
1669 struct tnode *p;
1670 int idx;
1671 struct node *trie = rcu_dereference(t->trie);
1672
1673 if (c == NULL) {
1674 if (trie == NULL)
1675 return NULL;
1676
1677 if (IS_LEAF(trie)) /* trie w. just a leaf */
1678 return (struct leaf *) trie;
1679
1680 p = (struct tnode*) trie; /* Start */
1681 } else
1682 p = (struct tnode *) NODE_PARENT(c);
1683
1684 while (p) {
1685 int pos, last;
1686
1687 /* Find the next child of the parent */
1688 if (c)
1689 pos = 1 + tkey_extract_bits(c->key, p->pos, p->bits);
1690 else
1691 pos = 0;
1692
1693 last = 1 << p->bits;
1694 for (idx = pos; idx < last ; idx++) {
1695 c = rcu_dereference(p->child[idx]);
1696
1697 if (!c)
1698 continue;
1699
1700 /* Decend if tnode */
1701 while (IS_TNODE(c)) {
1702 p = (struct tnode *) c;
1703 idx = 0;
1704
1705 /* Rightmost non-NULL branch */
1706 if (p && IS_TNODE(p))
1707 while (!(c = rcu_dereference(p->child[idx]))
1708 && idx < (1<<p->bits)) idx++;
1709
1710 /* Done with this tnode? */
1711 if (idx >= (1 << p->bits) || !c)
1712 goto up;
1713 }
1714 return (struct leaf *) c;
1715 }
1716 up:
1717 /* No more children go up one step */
1718 c = (struct node *) p;
1719 p = (struct tnode *) NODE_PARENT(p);
1720 }
1721 return NULL; /* Ready. Root of trie */
1722 }
1723
1724 static int fn_trie_flush(struct fib_table *tb)
1725 {
1726 struct trie *t = (struct trie *) tb->tb_data;
1727 struct leaf *ll = NULL, *l = NULL;
1728 int found = 0, h;
1729
1730 t->revision++;
1731
1732 for (h = 0; (l = nextleaf(t, l)) != NULL; h++) {
1733 found += trie_flush_leaf(t, l);
1734
1735 if (ll && hlist_empty(&ll->list))
1736 trie_leaf_remove(t, ll->key);
1737 ll = l;
1738 }
1739
1740 if (ll && hlist_empty(&ll->list))
1741 trie_leaf_remove(t, ll->key);
1742
1743 pr_debug("trie_flush found=%d\n", found);
1744 return found;
1745 }
1746
1747 static int trie_last_dflt = -1;
1748
1749 static void
1750 fn_trie_select_default(struct fib_table *tb, const struct flowi *flp, struct fib_result *res)
1751 {
1752 struct trie *t = (struct trie *) tb->tb_data;
1753 int order, last_idx;
1754 struct fib_info *fi = NULL;
1755 struct fib_info *last_resort;
1756 struct fib_alias *fa = NULL;
1757 struct list_head *fa_head;
1758 struct leaf *l;
1759
1760 last_idx = -1;
1761 last_resort = NULL;
1762 order = -1;
1763
1764 rcu_read_lock();
1765
1766 l = fib_find_node(t, 0);
1767 if (!l)
1768 goto out;
1769
1770 fa_head = get_fa_head(l, 0);
1771 if (!fa_head)
1772 goto out;
1773
1774 if (list_empty(fa_head))
1775 goto out;
1776
1777 list_for_each_entry_rcu(fa, fa_head, fa_list) {
1778 struct fib_info *next_fi = fa->fa_info;
1779
1780 if (fa->fa_scope != res->scope ||
1781 fa->fa_type != RTN_UNICAST)
1782 continue;
1783
1784 if (next_fi->fib_priority > res->fi->fib_priority)
1785 break;
1786 if (!next_fi->fib_nh[0].nh_gw ||
1787 next_fi->fib_nh[0].nh_scope != RT_SCOPE_LINK)
1788 continue;
1789 fa->fa_state |= FA_S_ACCESSED;
1790
1791 if (fi == NULL) {
1792 if (next_fi != res->fi)
1793 break;
1794 } else if (!fib_detect_death(fi, order, &last_resort,
1795 &last_idx, &trie_last_dflt)) {
1796 if (res->fi)
1797 fib_info_put(res->fi);
1798 res->fi = fi;
1799 atomic_inc(&fi->fib_clntref);
1800 trie_last_dflt = order;
1801 goto out;
1802 }
1803 fi = next_fi;
1804 order++;
1805 }
1806 if (order <= 0 || fi == NULL) {
1807 trie_last_dflt = -1;
1808 goto out;
1809 }
1810
1811 if (!fib_detect_death(fi, order, &last_resort, &last_idx, &trie_last_dflt)) {
1812 if (res->fi)
1813 fib_info_put(res->fi);
1814 res->fi = fi;
1815 atomic_inc(&fi->fib_clntref);
1816 trie_last_dflt = order;
1817 goto out;
1818 }
1819 if (last_idx >= 0) {
1820 if (res->fi)
1821 fib_info_put(res->fi);
1822 res->fi = last_resort;
1823 if (last_resort)
1824 atomic_inc(&last_resort->fib_clntref);
1825 }
1826 trie_last_dflt = last_idx;
1827 out:;
1828 rcu_read_unlock();
1829 }
1830
1831 static int fn_trie_dump_fa(t_key key, int plen, struct list_head *fah, struct fib_table *tb,
1832 struct sk_buff *skb, struct netlink_callback *cb)
1833 {
1834 int i, s_i;
1835 struct fib_alias *fa;
1836
1837 __be32 xkey = htonl(key);
1838
1839 s_i = cb->args[4];
1840 i = 0;
1841
1842 /* rcu_read_lock is hold by caller */
1843
1844 list_for_each_entry_rcu(fa, fah, fa_list) {
1845 if (i < s_i) {
1846 i++;
1847 continue;
1848 }
1849 BUG_ON(!fa->fa_info);
1850
1851 if (fib_dump_info(skb, NETLINK_CB(cb->skb).pid,
1852 cb->nlh->nlmsg_seq,
1853 RTM_NEWROUTE,
1854 tb->tb_id,
1855 fa->fa_type,
1856 fa->fa_scope,
1857 xkey,
1858 plen,
1859 fa->fa_tos,
1860 fa->fa_info, 0) < 0) {
1861 cb->args[4] = i;
1862 return -1;
1863 }
1864 i++;
1865 }
1866 cb->args[4] = i;
1867 return skb->len;
1868 }
1869
1870 static int fn_trie_dump_plen(struct trie *t, int plen, struct fib_table *tb, struct sk_buff *skb,
1871 struct netlink_callback *cb)
1872 {
1873 int h, s_h;
1874 struct list_head *fa_head;
1875 struct leaf *l = NULL;
1876
1877 s_h = cb->args[3];
1878
1879 for (h = 0; (l = nextleaf(t, l)) != NULL; h++) {
1880 if (h < s_h)
1881 continue;
1882 if (h > s_h)
1883 memset(&cb->args[4], 0,
1884 sizeof(cb->args) - 4*sizeof(cb->args[0]));
1885
1886 fa_head = get_fa_head(l, plen);
1887
1888 if (!fa_head)
1889 continue;
1890
1891 if (list_empty(fa_head))
1892 continue;
1893
1894 if (fn_trie_dump_fa(l->key, plen, fa_head, tb, skb, cb)<0) {
1895 cb->args[3] = h;
1896 return -1;
1897 }
1898 }
1899 cb->args[3] = h;
1900 return skb->len;
1901 }
1902
1903 static int fn_trie_dump(struct fib_table *tb, struct sk_buff *skb, struct netlink_callback *cb)
1904 {
1905 int m, s_m;
1906 struct trie *t = (struct trie *) tb->tb_data;
1907
1908 s_m = cb->args[2];
1909
1910 rcu_read_lock();
1911 for (m = 0; m <= 32; m++) {
1912 if (m < s_m)
1913 continue;
1914 if (m > s_m)
1915 memset(&cb->args[3], 0,
1916 sizeof(cb->args) - 3*sizeof(cb->args[0]));
1917
1918 if (fn_trie_dump_plen(t, 32-m, tb, skb, cb)<0) {
1919 cb->args[2] = m;
1920 goto out;
1921 }
1922 }
1923 rcu_read_unlock();
1924 cb->args[2] = m;
1925 return skb->len;
1926 out:
1927 rcu_read_unlock();
1928 return -1;
1929 }
1930
1931 /* Fix more generic FIB names for init later */
1932
1933 #ifdef CONFIG_IP_MULTIPLE_TABLES
1934 struct fib_table * fib_hash_init(u32 id)
1935 #else
1936 struct fib_table * __init fib_hash_init(u32 id)
1937 #endif
1938 {
1939 struct fib_table *tb;
1940 struct trie *t;
1941
1942 if (fn_alias_kmem == NULL)
1943 fn_alias_kmem = kmem_cache_create("ip_fib_alias",
1944 sizeof(struct fib_alias),
1945 0, SLAB_HWCACHE_ALIGN,
1946 NULL, NULL);
1947
1948 tb = kmalloc(sizeof(struct fib_table) + sizeof(struct trie),
1949 GFP_KERNEL);
1950 if (tb == NULL)
1951 return NULL;
1952
1953 tb->tb_id = id;
1954 tb->tb_lookup = fn_trie_lookup;
1955 tb->tb_insert = fn_trie_insert;
1956 tb->tb_delete = fn_trie_delete;
1957 tb->tb_flush = fn_trie_flush;
1958 tb->tb_select_default = fn_trie_select_default;
1959 tb->tb_dump = fn_trie_dump;
1960 memset(tb->tb_data, 0, sizeof(struct trie));
1961
1962 t = (struct trie *) tb->tb_data;
1963
1964 trie_init(t);
1965
1966 if (id == RT_TABLE_LOCAL)
1967 trie_local = t;
1968 else if (id == RT_TABLE_MAIN)
1969 trie_main = t;
1970
1971 if (id == RT_TABLE_LOCAL)
1972 printk(KERN_INFO "IPv4 FIB: Using LC-trie version %s\n", VERSION);
1973
1974 return tb;
1975 }
1976
1977 #ifdef CONFIG_PROC_FS
1978 /* Depth first Trie walk iterator */
1979 struct fib_trie_iter {
1980 struct tnode *tnode;
1981 struct trie *trie;
1982 unsigned index;
1983 unsigned depth;
1984 };
1985
1986 static struct node *fib_trie_get_next(struct fib_trie_iter *iter)
1987 {
1988 struct tnode *tn = iter->tnode;
1989 unsigned cindex = iter->index;
1990 struct tnode *p;
1991
1992 /* A single entry routing table */
1993 if (!tn)
1994 return NULL;
1995
1996 pr_debug("get_next iter={node=%p index=%d depth=%d}\n",
1997 iter->tnode, iter->index, iter->depth);
1998 rescan:
1999 while (cindex < (1<<tn->bits)) {
2000 struct node *n = tnode_get_child(tn, cindex);
2001
2002 if (n) {
2003 if (IS_LEAF(n)) {
2004 iter->tnode = tn;
2005 iter->index = cindex + 1;
2006 } else {
2007 /* push down one level */
2008 iter->tnode = (struct tnode *) n;
2009 iter->index = 0;
2010 ++iter->depth;
2011 }
2012 return n;
2013 }
2014
2015 ++cindex;
2016 }
2017
2018 /* Current node exhausted, pop back up */
2019 p = NODE_PARENT(tn);
2020 if (p) {
2021 cindex = tkey_extract_bits(tn->key, p->pos, p->bits)+1;
2022 tn = p;
2023 --iter->depth;
2024 goto rescan;
2025 }
2026
2027 /* got root? */
2028 return NULL;
2029 }
2030
2031 static struct node *fib_trie_get_first(struct fib_trie_iter *iter,
2032 struct trie *t)
2033 {
2034 struct node *n ;
2035
2036 if(!t)
2037 return NULL;
2038
2039 n = rcu_dereference(t->trie);
2040
2041 if(!iter)
2042 return NULL;
2043
2044 if (n) {
2045 if (IS_TNODE(n)) {
2046 iter->tnode = (struct tnode *) n;
2047 iter->trie = t;
2048 iter->index = 0;
2049 iter->depth = 1;
2050 } else {
2051 iter->tnode = NULL;
2052 iter->trie = t;
2053 iter->index = 0;
2054 iter->depth = 0;
2055 }
2056 return n;
2057 }
2058 return NULL;
2059 }
2060
2061 static void trie_collect_stats(struct trie *t, struct trie_stat *s)
2062 {
2063 struct node *n;
2064 struct fib_trie_iter iter;
2065
2066 memset(s, 0, sizeof(*s));
2067
2068 rcu_read_lock();
2069 for (n = fib_trie_get_first(&iter, t); n;
2070 n = fib_trie_get_next(&iter)) {
2071 if (IS_LEAF(n)) {
2072 s->leaves++;
2073 s->totdepth += iter.depth;
2074 if (iter.depth > s->maxdepth)
2075 s->maxdepth = iter.depth;
2076 } else {
2077 const struct tnode *tn = (const struct tnode *) n;
2078 int i;
2079
2080 s->tnodes++;
2081 if(tn->bits < MAX_STAT_DEPTH)
2082 s->nodesizes[tn->bits]++;
2083
2084 for (i = 0; i < (1<<tn->bits); i++)
2085 if (!tn->child[i])
2086 s->nullpointers++;
2087 }
2088 }
2089 rcu_read_unlock();
2090 }
2091
2092 /*
2093 * This outputs /proc/net/fib_triestats
2094 */
2095 static void trie_show_stats(struct seq_file *seq, struct trie_stat *stat)
2096 {
2097 unsigned i, max, pointers, bytes, avdepth;
2098
2099 if (stat->leaves)
2100 avdepth = stat->totdepth*100 / stat->leaves;
2101 else
2102 avdepth = 0;
2103
2104 seq_printf(seq, "\tAver depth: %d.%02d\n", avdepth / 100, avdepth % 100 );
2105 seq_printf(seq, "\tMax depth: %u\n", stat->maxdepth);
2106
2107 seq_printf(seq, "\tLeaves: %u\n", stat->leaves);
2108
2109 bytes = sizeof(struct leaf) * stat->leaves;
2110 seq_printf(seq, "\tInternal nodes: %d\n\t", stat->tnodes);
2111 bytes += sizeof(struct tnode) * stat->tnodes;
2112
2113 max = MAX_STAT_DEPTH;
2114 while (max > 0 && stat->nodesizes[max-1] == 0)
2115 max--;
2116
2117 pointers = 0;
2118 for (i = 1; i <= max; i++)
2119 if (stat->nodesizes[i] != 0) {
2120 seq_printf(seq, " %d: %d", i, stat->nodesizes[i]);
2121 pointers += (1<<i) * stat->nodesizes[i];
2122 }
2123 seq_putc(seq, '\n');
2124 seq_printf(seq, "\tPointers: %d\n", pointers);
2125
2126 bytes += sizeof(struct node *) * pointers;
2127 seq_printf(seq, "Null ptrs: %d\n", stat->nullpointers);
2128 seq_printf(seq, "Total size: %d kB\n", (bytes + 1023) / 1024);
2129
2130 #ifdef CONFIG_IP_FIB_TRIE_STATS
2131 seq_printf(seq, "Counters:\n---------\n");
2132 seq_printf(seq,"gets = %d\n", t->stats.gets);
2133 seq_printf(seq,"backtracks = %d\n", t->stats.backtrack);
2134 seq_printf(seq,"semantic match passed = %d\n", t->stats.semantic_match_passed);
2135 seq_printf(seq,"semantic match miss = %d\n", t->stats.semantic_match_miss);
2136 seq_printf(seq,"null node hit= %d\n", t->stats.null_node_hit);
2137 seq_printf(seq,"skipped node resize = %d\n", t->stats.resize_node_skipped);
2138 #ifdef CLEAR_STATS
2139 memset(&(t->stats), 0, sizeof(t->stats));
2140 #endif
2141 #endif /* CONFIG_IP_FIB_TRIE_STATS */
2142 }
2143
2144 static int fib_triestat_seq_show(struct seq_file *seq, void *v)
2145 {
2146 struct trie_stat *stat;
2147
2148 stat = kmalloc(sizeof(*stat), GFP_KERNEL);
2149 if (!stat)
2150 return -ENOMEM;
2151
2152 seq_printf(seq, "Basic info: size of leaf: %Zd bytes, size of tnode: %Zd bytes.\n",
2153 sizeof(struct leaf), sizeof(struct tnode));
2154
2155 if (trie_local) {
2156 seq_printf(seq, "Local:\n");
2157 trie_collect_stats(trie_local, stat);
2158 trie_show_stats(seq, stat);
2159 }
2160
2161 if (trie_main) {
2162 seq_printf(seq, "Main:\n");
2163 trie_collect_stats(trie_main, stat);
2164 trie_show_stats(seq, stat);
2165 }
2166 kfree(stat);
2167
2168 return 0;
2169 }
2170
2171 static int fib_triestat_seq_open(struct inode *inode, struct file *file)
2172 {
2173 return single_open(file, fib_triestat_seq_show, NULL);
2174 }
2175
2176 static const struct file_operations fib_triestat_fops = {
2177 .owner = THIS_MODULE,
2178 .open = fib_triestat_seq_open,
2179 .read = seq_read,
2180 .llseek = seq_lseek,
2181 .release = single_release,
2182 };
2183
2184 static struct node *fib_trie_get_idx(struct fib_trie_iter *iter,
2185 loff_t pos)
2186 {
2187 loff_t idx = 0;
2188 struct node *n;
2189
2190 for (n = fib_trie_get_first(iter, trie_local);
2191 n; ++idx, n = fib_trie_get_next(iter)) {
2192 if (pos == idx)
2193 return n;
2194 }
2195
2196 for (n = fib_trie_get_first(iter, trie_main);
2197 n; ++idx, n = fib_trie_get_next(iter)) {
2198 if (pos == idx)
2199 return n;
2200 }
2201 return NULL;
2202 }
2203
2204 static void *fib_trie_seq_start(struct seq_file *seq, loff_t *pos)
2205 {
2206 rcu_read_lock();
2207 if (*pos == 0)
2208 return SEQ_START_TOKEN;
2209 return fib_trie_get_idx(seq->private, *pos - 1);
2210 }
2211
2212 static void *fib_trie_seq_next(struct seq_file *seq, void *v, loff_t *pos)
2213 {
2214 struct fib_trie_iter *iter = seq->private;
2215 void *l = v;
2216
2217 ++*pos;
2218 if (v == SEQ_START_TOKEN)
2219 return fib_trie_get_idx(iter, 0);
2220
2221 v = fib_trie_get_next(iter);
2222 BUG_ON(v == l);
2223 if (v)
2224 return v;
2225
2226 /* continue scan in next trie */
2227 if (iter->trie == trie_local)
2228 return fib_trie_get_first(iter, trie_main);
2229
2230 return NULL;
2231 }
2232
2233 static void fib_trie_seq_stop(struct seq_file *seq, void *v)
2234 {
2235 rcu_read_unlock();
2236 }
2237
2238 static void seq_indent(struct seq_file *seq, int n)
2239 {
2240 while (n-- > 0) seq_puts(seq, " ");
2241 }
2242
2243 static inline const char *rtn_scope(enum rt_scope_t s)
2244 {
2245 static char buf[32];
2246
2247 switch(s) {
2248 case RT_SCOPE_UNIVERSE: return "universe";
2249 case RT_SCOPE_SITE: return "site";
2250 case RT_SCOPE_LINK: return "link";
2251 case RT_SCOPE_HOST: return "host";
2252 case RT_SCOPE_NOWHERE: return "nowhere";
2253 default:
2254 snprintf(buf, sizeof(buf), "scope=%d", s);
2255 return buf;
2256 }
2257 }
2258
2259 static const char *rtn_type_names[__RTN_MAX] = {
2260 [RTN_UNSPEC] = "UNSPEC",
2261 [RTN_UNICAST] = "UNICAST",
2262 [RTN_LOCAL] = "LOCAL",
2263 [RTN_BROADCAST] = "BROADCAST",
2264 [RTN_ANYCAST] = "ANYCAST",
2265 [RTN_MULTICAST] = "MULTICAST",
2266 [RTN_BLACKHOLE] = "BLACKHOLE",
2267 [RTN_UNREACHABLE] = "UNREACHABLE",
2268 [RTN_PROHIBIT] = "PROHIBIT",
2269 [RTN_THROW] = "THROW",
2270 [RTN_NAT] = "NAT",
2271 [RTN_XRESOLVE] = "XRESOLVE",
2272 };
2273
2274 static inline const char *rtn_type(unsigned t)
2275 {
2276 static char buf[32];
2277
2278 if (t < __RTN_MAX && rtn_type_names[t])
2279 return rtn_type_names[t];
2280 snprintf(buf, sizeof(buf), "type %d", t);
2281 return buf;
2282 }
2283
2284 /* Pretty print the trie */
2285 static int fib_trie_seq_show(struct seq_file *seq, void *v)
2286 {
2287 const struct fib_trie_iter *iter = seq->private;
2288 struct node *n = v;
2289
2290 if (v == SEQ_START_TOKEN)
2291 return 0;
2292
2293 if (!NODE_PARENT(n)) {
2294 if (iter->trie == trie_local)
2295 seq_puts(seq, "<local>:\n");
2296 else
2297 seq_puts(seq, "<main>:\n");
2298 }
2299
2300 if (IS_TNODE(n)) {
2301 struct tnode *tn = (struct tnode *) n;
2302 __be32 prf = htonl(MASK_PFX(tn->key, tn->pos));
2303
2304 seq_indent(seq, iter->depth-1);
2305 seq_printf(seq, " +-- %d.%d.%d.%d/%d %d %d %d\n",
2306 NIPQUAD(prf), tn->pos, tn->bits, tn->full_children,
2307 tn->empty_children);
2308
2309 } else {
2310 struct leaf *l = (struct leaf *) n;
2311 int i;
2312 __be32 val = htonl(l->key);
2313
2314 seq_indent(seq, iter->depth);
2315 seq_printf(seq, " |-- %d.%d.%d.%d\n", NIPQUAD(val));
2316 for (i = 32; i >= 0; i--) {
2317 struct leaf_info *li = find_leaf_info(l, i);
2318 if (li) {
2319 struct fib_alias *fa;
2320 list_for_each_entry_rcu(fa, &li->falh, fa_list) {
2321 seq_indent(seq, iter->depth+1);
2322 seq_printf(seq, " /%d %s %s", i,
2323 rtn_scope(fa->fa_scope),
2324 rtn_type(fa->fa_type));
2325 if (fa->fa_tos)
2326 seq_printf(seq, "tos =%d\n",
2327 fa->fa_tos);
2328 seq_putc(seq, '\n');
2329 }
2330 }
2331 }
2332 }
2333
2334 return 0;
2335 }
2336
2337 static struct seq_operations fib_trie_seq_ops = {
2338 .start = fib_trie_seq_start,
2339 .next = fib_trie_seq_next,
2340 .stop = fib_trie_seq_stop,
2341 .show = fib_trie_seq_show,
2342 };
2343
2344 static int fib_trie_seq_open(struct inode *inode, struct file *file)
2345 {
2346 struct seq_file *seq;
2347 int rc = -ENOMEM;
2348 struct fib_trie_iter *s = kmalloc(sizeof(*s), GFP_KERNEL);
2349
2350 if (!s)
2351 goto out;
2352
2353 rc = seq_open(file, &fib_trie_seq_ops);
2354 if (rc)
2355 goto out_kfree;
2356
2357 seq = file->private_data;
2358 seq->private = s;
2359 memset(s, 0, sizeof(*s));
2360 out:
2361 return rc;
2362 out_kfree:
2363 kfree(s);
2364 goto out;
2365 }
2366
2367 static const struct file_operations fib_trie_fops = {
2368 .owner = THIS_MODULE,
2369 .open = fib_trie_seq_open,
2370 .read = seq_read,
2371 .llseek = seq_lseek,
2372 .release = seq_release_private,
2373 };
2374
2375 static unsigned fib_flag_trans(int type, __be32 mask, const struct fib_info *fi)
2376 {
2377 static unsigned type2flags[RTN_MAX + 1] = {
2378 [7] = RTF_REJECT, [8] = RTF_REJECT,
2379 };
2380 unsigned flags = type2flags[type];
2381
2382 if (fi && fi->fib_nh->nh_gw)
2383 flags |= RTF_GATEWAY;
2384 if (mask == htonl(0xFFFFFFFF))
2385 flags |= RTF_HOST;
2386 flags |= RTF_UP;
2387 return flags;
2388 }
2389
2390 /*
2391 * This outputs /proc/net/route.
2392 * The format of the file is not supposed to be changed
2393 * and needs to be same as fib_hash output to avoid breaking
2394 * legacy utilities
2395 */
2396 static int fib_route_seq_show(struct seq_file *seq, void *v)
2397 {
2398 const struct fib_trie_iter *iter = seq->private;
2399 struct leaf *l = v;
2400 int i;
2401 char bf[128];
2402
2403 if (v == SEQ_START_TOKEN) {
2404 seq_printf(seq, "%-127s\n", "Iface\tDestination\tGateway "
2405 "\tFlags\tRefCnt\tUse\tMetric\tMask\t\tMTU"
2406 "\tWindow\tIRTT");
2407 return 0;
2408 }
2409
2410 if (iter->trie == trie_local)
2411 return 0;
2412 if (IS_TNODE(l))
2413 return 0;
2414
2415 for (i=32; i>=0; i--) {
2416 struct leaf_info *li = find_leaf_info(l, i);
2417 struct fib_alias *fa;
2418 __be32 mask, prefix;
2419
2420 if (!li)
2421 continue;
2422
2423 mask = inet_make_mask(li->plen);
2424 prefix = htonl(l->key);
2425
2426 list_for_each_entry_rcu(fa, &li->falh, fa_list) {
2427 const struct fib_info *fi = fa->fa_info;
2428 unsigned flags = fib_flag_trans(fa->fa_type, mask, fi);
2429
2430 if (fa->fa_type == RTN_BROADCAST
2431 || fa->fa_type == RTN_MULTICAST)
2432 continue;
2433
2434 if (fi)
2435 snprintf(bf, sizeof(bf),
2436 "%s\t%08X\t%08X\t%04X\t%d\t%u\t%d\t%08X\t%d\t%u\t%u",
2437 fi->fib_dev ? fi->fib_dev->name : "*",
2438 prefix,
2439 fi->fib_nh->nh_gw, flags, 0, 0,
2440 fi->fib_priority,
2441 mask,
2442 (fi->fib_advmss ? fi->fib_advmss + 40 : 0),
2443 fi->fib_window,
2444 fi->fib_rtt >> 3);
2445 else
2446 snprintf(bf, sizeof(bf),
2447 "*\t%08X\t%08X\t%04X\t%d\t%u\t%d\t%08X\t%d\t%u\t%u",
2448 prefix, 0, flags, 0, 0, 0,
2449 mask, 0, 0, 0);
2450
2451 seq_printf(seq, "%-127s\n", bf);
2452 }
2453 }
2454
2455 return 0;
2456 }
2457
2458 static struct seq_operations fib_route_seq_ops = {
2459 .start = fib_trie_seq_start,
2460 .next = fib_trie_seq_next,
2461 .stop = fib_trie_seq_stop,
2462 .show = fib_route_seq_show,
2463 };
2464
2465 static int fib_route_seq_open(struct inode *inode, struct file *file)
2466 {
2467 struct seq_file *seq;
2468 int rc = -ENOMEM;
2469 struct fib_trie_iter *s = kmalloc(sizeof(*s), GFP_KERNEL);
2470
2471 if (!s)
2472 goto out;
2473
2474 rc = seq_open(file, &fib_route_seq_ops);
2475 if (rc)
2476 goto out_kfree;
2477
2478 seq = file->private_data;
2479 seq->private = s;
2480 memset(s, 0, sizeof(*s));
2481 out:
2482 return rc;
2483 out_kfree:
2484 kfree(s);
2485 goto out;
2486 }
2487
2488 static const struct file_operations fib_route_fops = {
2489 .owner = THIS_MODULE,
2490 .open = fib_route_seq_open,
2491 .read = seq_read,
2492 .llseek = seq_lseek,
2493 .release = seq_release_private,
2494 };
2495
2496 int __init fib_proc_init(void)
2497 {
2498 if (!proc_net_fops_create("fib_trie", S_IRUGO, &fib_trie_fops))
2499 goto out1;
2500
2501 if (!proc_net_fops_create("fib_triestat", S_IRUGO, &fib_triestat_fops))
2502 goto out2;
2503
2504 if (!proc_net_fops_create("route", S_IRUGO, &fib_route_fops))
2505 goto out3;
2506
2507 return 0;
2508
2509 out3:
2510 proc_net_remove("fib_triestat");
2511 out2:
2512 proc_net_remove("fib_trie");
2513 out1:
2514 return -ENOMEM;
2515 }
2516
2517 void __init fib_proc_exit(void)
2518 {
2519 proc_net_remove("fib_trie");
2520 proc_net_remove("fib_triestat");
2521 proc_net_remove("route");
2522 }
2523
2524 #endif /* CONFIG_PROC_FS */
Linux 2.6 ibm-acpi/thinkpad-acpi driver git tree