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 described 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.csc.kth.se/~snilsson/software/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
26 * Code from fib_hash has been reused which includes the following header:
29 * INET An implementation of the TCP/IP protocol suite for the LINUX
30 * operating system. INET is implemented using the BSD Socket
31 * interface as the means of communication with the user level.
33 * IPv4 FIB: lookup engine and maintenance routines.
36 * Authors: Alexey Kuznetsov, <kuznet@ms2.inr.ac.ru>
38 * This program is free software; you can redistribute it and/or
39 * modify it under the terms of the GNU General Public License
40 * as published by the Free Software Foundation; either version
41 * 2 of the License, or (at your option) any later version.
43 * Substantial contributions to this work comes from:
45 * David S. Miller, <davem@davemloft.net>
46 * Stephen Hemminger <shemminger@osdl.org>
47 * Paul E. McKenney <paulmck@us.ibm.com>
48 * Patrick McHardy <kaber@trash.net>
51 #define VERSION "0.409"
53 #include <linux/uaccess.h>
54 #include <linux/bitops.h>
55 #include <linux/types.h>
56 #include <linux/kernel.h>
58 #include <linux/string.h>
59 #include <linux/socket.h>
60 #include <linux/sockios.h>
61 #include <linux/errno.h>
63 #include <linux/inet.h>
64 #include <linux/inetdevice.h>
65 #include <linux/netdevice.h>
66 #include <linux/if_arp.h>
67 #include <linux/proc_fs.h>
68 #include <linux/rcupdate.h>
69 #include <linux/skbuff.h>
70 #include <linux/netlink.h>
71 #include <linux/init.h>
72 #include <linux/list.h>
73 #include <linux/slab.h>
74 #include <linux/export.h>
75 #include <linux/vmalloc.h>
76 #include <linux/notifier.h>
77 #include <net/net_namespace.h>
79 #include <net/protocol.h>
80 #include <net/route.h>
83 #include <net/ip_fib.h>
84 #include <trace/events/fib.h>
85 #include "fib_lookup.h"
87 static int call_fib_entry_notifier(struct notifier_block
*nb
, struct net
*net
,
88 enum fib_event_type event_type
, u32 dst
,
89 int dst_len
, struct fib_info
*fi
,
90 u8 tos
, u8 type
, u32 tb_id
)
92 struct fib_entry_notifier_info info
= {
100 return call_fib_notifier(nb
, net
, event_type
, &info
.info
);
103 static int call_fib_entry_notifiers(struct net
*net
,
104 enum fib_event_type event_type
, u32 dst
,
105 int dst_len
, struct fib_info
*fi
,
106 u8 tos
, u8 type
, u32 tb_id
)
108 struct fib_entry_notifier_info info
= {
116 return call_fib_notifiers(net
, event_type
, &info
.info
);
119 #define MAX_STAT_DEPTH 32
121 #define KEYLENGTH (8*sizeof(t_key))
122 #define KEY_MAX ((t_key)~0)
124 typedef unsigned int t_key
;
126 #define IS_TRIE(n) ((n)->pos >= KEYLENGTH)
127 #define IS_TNODE(n) ((n)->bits)
128 #define IS_LEAF(n) (!(n)->bits)
132 unsigned char pos
; /* 2log(KEYLENGTH) bits needed */
133 unsigned char bits
; /* 2log(KEYLENGTH) bits needed */
136 /* This list pointer if valid if (pos | bits) == 0 (LEAF) */
137 struct hlist_head leaf
;
138 /* This array is valid if (pos | bits) > 0 (TNODE) */
139 struct key_vector __rcu
*tnode
[0];
145 t_key empty_children
; /* KEYLENGTH bits needed */
146 t_key full_children
; /* KEYLENGTH bits needed */
147 struct key_vector __rcu
*parent
;
148 struct key_vector kv
[1];
149 #define tn_bits kv[0].bits
152 #define TNODE_SIZE(n) offsetof(struct tnode, kv[0].tnode[n])
153 #define LEAF_SIZE TNODE_SIZE(1)
155 #ifdef CONFIG_IP_FIB_TRIE_STATS
156 struct trie_use_stats
{
158 unsigned int backtrack
;
159 unsigned int semantic_match_passed
;
160 unsigned int semantic_match_miss
;
161 unsigned int null_node_hit
;
162 unsigned int resize_node_skipped
;
167 unsigned int totdepth
;
168 unsigned int maxdepth
;
171 unsigned int nullpointers
;
172 unsigned int prefixes
;
173 unsigned int nodesizes
[MAX_STAT_DEPTH
];
177 struct key_vector kv
[1];
178 #ifdef CONFIG_IP_FIB_TRIE_STATS
179 struct trie_use_stats __percpu
*stats
;
183 static struct key_vector
*resize(struct trie
*t
, struct key_vector
*tn
);
184 static size_t tnode_free_size
;
187 * synchronize_rcu after call_rcu for that many pages; it should be especially
188 * useful before resizing the root node with PREEMPT_NONE configs; the value was
189 * obtained experimentally, aiming to avoid visible slowdown.
191 static const int sync_pages
= 128;
193 static struct kmem_cache
*fn_alias_kmem __read_mostly
;
194 static struct kmem_cache
*trie_leaf_kmem __read_mostly
;
196 static inline struct tnode
*tn_info(struct key_vector
*kv
)
198 return container_of(kv
, struct tnode
, kv
[0]);
201 /* caller must hold RTNL */
202 #define node_parent(tn) rtnl_dereference(tn_info(tn)->parent)
203 #define get_child(tn, i) rtnl_dereference((tn)->tnode[i])
205 /* caller must hold RCU read lock or RTNL */
206 #define node_parent_rcu(tn) rcu_dereference_rtnl(tn_info(tn)->parent)
207 #define get_child_rcu(tn, i) rcu_dereference_rtnl((tn)->tnode[i])
209 /* wrapper for rcu_assign_pointer */
210 static inline void node_set_parent(struct key_vector
*n
, struct key_vector
*tp
)
213 rcu_assign_pointer(tn_info(n
)->parent
, tp
);
216 #define NODE_INIT_PARENT(n, p) RCU_INIT_POINTER(tn_info(n)->parent, p)
218 /* This provides us with the number of children in this node, in the case of a
219 * leaf this will return 0 meaning none of the children are accessible.
221 static inline unsigned long child_length(const struct key_vector
*tn
)
223 return (1ul << tn
->bits
) & ~(1ul);
226 #define get_cindex(key, kv) (((key) ^ (kv)->key) >> (kv)->pos)
228 static inline unsigned long get_index(t_key key
, struct key_vector
*kv
)
230 unsigned long index
= key
^ kv
->key
;
232 if ((BITS_PER_LONG
<= KEYLENGTH
) && (KEYLENGTH
== kv
->pos
))
235 return index
>> kv
->pos
;
238 /* To understand this stuff, an understanding of keys and all their bits is
239 * necessary. Every node in the trie has a key associated with it, but not
240 * all of the bits in that key are significant.
242 * Consider a node 'n' and its parent 'tp'.
244 * If n is a leaf, every bit in its key is significant. Its presence is
245 * necessitated by path compression, since during a tree traversal (when
246 * searching for a leaf - unless we are doing an insertion) we will completely
247 * ignore all skipped bits we encounter. Thus we need to verify, at the end of
248 * a potentially successful search, that we have indeed been walking the
251 * Note that we can never "miss" the correct key in the tree if present by
252 * following the wrong path. Path compression ensures that segments of the key
253 * that are the same for all keys with a given prefix are skipped, but the
254 * skipped part *is* identical for each node in the subtrie below the skipped
255 * bit! trie_insert() in this implementation takes care of that.
257 * if n is an internal node - a 'tnode' here, the various parts of its key
258 * have many different meanings.
261 * _________________________________________________________________
262 * | i | i | i | i | i | i | i | N | N | N | S | S | S | S | S | C |
263 * -----------------------------------------------------------------
264 * 31 30 29 28 27 26 25 24 23 22 21 20 19 18 17 16
266 * _________________________________________________________________
267 * | C | C | C | u | u | u | u | u | u | u | u | u | u | u | u | u |
268 * -----------------------------------------------------------------
269 * 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0
276 * First, let's just ignore the bits that come before the parent tp, that is
277 * the bits from (tp->pos + tp->bits) to 31. They are *known* but at this
278 * point we do not use them for anything.
280 * The bits from (tp->pos) to (tp->pos + tp->bits - 1) - "N", above - are the
281 * index into the parent's child array. That is, they will be used to find
282 * 'n' among tp's children.
284 * The bits from (n->pos + n->bits) to (tp->pos - 1) - "S" - are skipped bits
287 * All the bits we have seen so far are significant to the node n. The rest
288 * of the bits are really not needed or indeed known in n->key.
290 * The bits from (n->pos) to (n->pos + n->bits - 1) - "C" - are the index into
291 * n's child array, and will of course be different for each child.
293 * The rest of the bits, from 0 to (n->pos -1) - "u" - are completely unknown
297 static const int halve_threshold
= 25;
298 static const int inflate_threshold
= 50;
299 static const int halve_threshold_root
= 15;
300 static const int inflate_threshold_root
= 30;
302 static void __alias_free_mem(struct rcu_head
*head
)
304 struct fib_alias
*fa
= container_of(head
, struct fib_alias
, rcu
);
305 kmem_cache_free(fn_alias_kmem
, fa
);
308 static inline void alias_free_mem_rcu(struct fib_alias
*fa
)
310 call_rcu(&fa
->rcu
, __alias_free_mem
);
313 #define TNODE_KMALLOC_MAX \
314 ilog2((PAGE_SIZE - TNODE_SIZE(0)) / sizeof(struct key_vector *))
315 #define TNODE_VMALLOC_MAX \
316 ilog2((SIZE_MAX - TNODE_SIZE(0)) / sizeof(struct key_vector *))
318 static void __node_free_rcu(struct rcu_head
*head
)
320 struct tnode
*n
= container_of(head
, struct tnode
, rcu
);
323 kmem_cache_free(trie_leaf_kmem
, n
);
328 #define node_free(n) call_rcu(&tn_info(n)->rcu, __node_free_rcu)
330 static struct tnode
*tnode_alloc(int bits
)
334 /* verify bits is within bounds */
335 if (bits
> TNODE_VMALLOC_MAX
)
338 /* determine size and verify it is non-zero and didn't overflow */
339 size
= TNODE_SIZE(1ul << bits
);
341 if (size
<= PAGE_SIZE
)
342 return kzalloc(size
, GFP_KERNEL
);
344 return vzalloc(size
);
347 static inline void empty_child_inc(struct key_vector
*n
)
349 ++tn_info(n
)->empty_children
? : ++tn_info(n
)->full_children
;
352 static inline void empty_child_dec(struct key_vector
*n
)
354 tn_info(n
)->empty_children
-- ? : tn_info(n
)->full_children
--;
357 static struct key_vector
*leaf_new(t_key key
, struct fib_alias
*fa
)
359 struct key_vector
*l
;
362 kv
= kmem_cache_alloc(trie_leaf_kmem
, GFP_KERNEL
);
366 /* initialize key vector */
371 l
->slen
= fa
->fa_slen
;
373 /* link leaf to fib alias */
374 INIT_HLIST_HEAD(&l
->leaf
);
375 hlist_add_head(&fa
->fa_list
, &l
->leaf
);
380 static struct key_vector
*tnode_new(t_key key
, int pos
, int bits
)
382 unsigned int shift
= pos
+ bits
;
383 struct key_vector
*tn
;
386 /* verify bits and pos their msb bits clear and values are valid */
387 BUG_ON(!bits
|| (shift
> KEYLENGTH
));
389 tnode
= tnode_alloc(bits
);
393 pr_debug("AT %p s=%zu %zu\n", tnode
, TNODE_SIZE(0),
394 sizeof(struct key_vector
*) << bits
);
396 if (bits
== KEYLENGTH
)
397 tnode
->full_children
= 1;
399 tnode
->empty_children
= 1ul << bits
;
402 tn
->key
= (shift
< KEYLENGTH
) ? (key
>> shift
) << shift
: 0;
410 /* Check whether a tnode 'n' is "full", i.e. it is an internal node
411 * and no bits are skipped. See discussion in dyntree paper p. 6
413 static inline int tnode_full(struct key_vector
*tn
, struct key_vector
*n
)
415 return n
&& ((n
->pos
+ n
->bits
) == tn
->pos
) && IS_TNODE(n
);
418 /* Add a child at position i overwriting the old value.
419 * Update the value of full_children and empty_children.
421 static void put_child(struct key_vector
*tn
, unsigned long i
,
422 struct key_vector
*n
)
424 struct key_vector
*chi
= get_child(tn
, i
);
427 BUG_ON(i
>= child_length(tn
));
429 /* update emptyChildren, overflow into fullChildren */
435 /* update fullChildren */
436 wasfull
= tnode_full(tn
, chi
);
437 isfull
= tnode_full(tn
, n
);
439 if (wasfull
&& !isfull
)
440 tn_info(tn
)->full_children
--;
441 else if (!wasfull
&& isfull
)
442 tn_info(tn
)->full_children
++;
444 if (n
&& (tn
->slen
< n
->slen
))
447 rcu_assign_pointer(tn
->tnode
[i
], n
);
450 static void update_children(struct key_vector
*tn
)
454 /* update all of the child parent pointers */
455 for (i
= child_length(tn
); i
;) {
456 struct key_vector
*inode
= get_child(tn
, --i
);
461 /* Either update the children of a tnode that
462 * already belongs to us or update the child
463 * to point to ourselves.
465 if (node_parent(inode
) == tn
)
466 update_children(inode
);
468 node_set_parent(inode
, tn
);
472 static inline void put_child_root(struct key_vector
*tp
, t_key key
,
473 struct key_vector
*n
)
476 rcu_assign_pointer(tp
->tnode
[0], n
);
478 put_child(tp
, get_index(key
, tp
), n
);
481 static inline void tnode_free_init(struct key_vector
*tn
)
483 tn_info(tn
)->rcu
.next
= NULL
;
486 static inline void tnode_free_append(struct key_vector
*tn
,
487 struct key_vector
*n
)
489 tn_info(n
)->rcu
.next
= tn_info(tn
)->rcu
.next
;
490 tn_info(tn
)->rcu
.next
= &tn_info(n
)->rcu
;
493 static void tnode_free(struct key_vector
*tn
)
495 struct callback_head
*head
= &tn_info(tn
)->rcu
;
499 tnode_free_size
+= TNODE_SIZE(1ul << tn
->bits
);
502 tn
= container_of(head
, struct tnode
, rcu
)->kv
;
505 if (tnode_free_size
>= PAGE_SIZE
* sync_pages
) {
511 static struct key_vector
*replace(struct trie
*t
,
512 struct key_vector
*oldtnode
,
513 struct key_vector
*tn
)
515 struct key_vector
*tp
= node_parent(oldtnode
);
518 /* setup the parent pointer out of and back into this node */
519 NODE_INIT_PARENT(tn
, tp
);
520 put_child_root(tp
, tn
->key
, tn
);
522 /* update all of the child parent pointers */
525 /* all pointers should be clean so we are done */
526 tnode_free(oldtnode
);
528 /* resize children now that oldtnode is freed */
529 for (i
= child_length(tn
); i
;) {
530 struct key_vector
*inode
= get_child(tn
, --i
);
532 /* resize child node */
533 if (tnode_full(tn
, inode
))
534 tn
= resize(t
, inode
);
540 static struct key_vector
*inflate(struct trie
*t
,
541 struct key_vector
*oldtnode
)
543 struct key_vector
*tn
;
547 pr_debug("In inflate\n");
549 tn
= tnode_new(oldtnode
->key
, oldtnode
->pos
- 1, oldtnode
->bits
+ 1);
553 /* prepare oldtnode to be freed */
554 tnode_free_init(oldtnode
);
556 /* Assemble all of the pointers in our cluster, in this case that
557 * represents all of the pointers out of our allocated nodes that
558 * point to existing tnodes and the links between our allocated
561 for (i
= child_length(oldtnode
), m
= 1u << tn
->pos
; i
;) {
562 struct key_vector
*inode
= get_child(oldtnode
, --i
);
563 struct key_vector
*node0
, *node1
;
570 /* A leaf or an internal node with skipped bits */
571 if (!tnode_full(oldtnode
, inode
)) {
572 put_child(tn
, get_index(inode
->key
, tn
), inode
);
576 /* drop the node in the old tnode free list */
577 tnode_free_append(oldtnode
, inode
);
579 /* An internal node with two children */
580 if (inode
->bits
== 1) {
581 put_child(tn
, 2 * i
+ 1, get_child(inode
, 1));
582 put_child(tn
, 2 * i
, get_child(inode
, 0));
586 /* We will replace this node 'inode' with two new
587 * ones, 'node0' and 'node1', each with half of the
588 * original children. The two new nodes will have
589 * a position one bit further down the key and this
590 * means that the "significant" part of their keys
591 * (see the discussion near the top of this file)
592 * will differ by one bit, which will be "0" in
593 * node0's key and "1" in node1's key. Since we are
594 * moving the key position by one step, the bit that
595 * we are moving away from - the bit at position
596 * (tn->pos) - is the one that will differ between
597 * node0 and node1. So... we synthesize that bit in the
600 node1
= tnode_new(inode
->key
| m
, inode
->pos
, inode
->bits
- 1);
603 node0
= tnode_new(inode
->key
, inode
->pos
, inode
->bits
- 1);
605 tnode_free_append(tn
, node1
);
608 tnode_free_append(tn
, node0
);
610 /* populate child pointers in new nodes */
611 for (k
= child_length(inode
), j
= k
/ 2; j
;) {
612 put_child(node1
, --j
, get_child(inode
, --k
));
613 put_child(node0
, j
, get_child(inode
, j
));
614 put_child(node1
, --j
, get_child(inode
, --k
));
615 put_child(node0
, j
, get_child(inode
, j
));
618 /* link new nodes to parent */
619 NODE_INIT_PARENT(node1
, tn
);
620 NODE_INIT_PARENT(node0
, tn
);
622 /* link parent to nodes */
623 put_child(tn
, 2 * i
+ 1, node1
);
624 put_child(tn
, 2 * i
, node0
);
627 /* setup the parent pointers into and out of this node */
628 return replace(t
, oldtnode
, tn
);
630 /* all pointers should be clean so we are done */
636 static struct key_vector
*halve(struct trie
*t
,
637 struct key_vector
*oldtnode
)
639 struct key_vector
*tn
;
642 pr_debug("In halve\n");
644 tn
= tnode_new(oldtnode
->key
, oldtnode
->pos
+ 1, oldtnode
->bits
- 1);
648 /* prepare oldtnode to be freed */
649 tnode_free_init(oldtnode
);
651 /* Assemble all of the pointers in our cluster, in this case that
652 * represents all of the pointers out of our allocated nodes that
653 * point to existing tnodes and the links between our allocated
656 for (i
= child_length(oldtnode
); i
;) {
657 struct key_vector
*node1
= get_child(oldtnode
, --i
);
658 struct key_vector
*node0
= get_child(oldtnode
, --i
);
659 struct key_vector
*inode
;
661 /* At least one of the children is empty */
662 if (!node1
|| !node0
) {
663 put_child(tn
, i
/ 2, node1
? : node0
);
667 /* Two nonempty children */
668 inode
= tnode_new(node0
->key
, oldtnode
->pos
, 1);
671 tnode_free_append(tn
, inode
);
673 /* initialize pointers out of node */
674 put_child(inode
, 1, node1
);
675 put_child(inode
, 0, node0
);
676 NODE_INIT_PARENT(inode
, tn
);
678 /* link parent to node */
679 put_child(tn
, i
/ 2, inode
);
682 /* setup the parent pointers into and out of this node */
683 return replace(t
, oldtnode
, tn
);
685 /* all pointers should be clean so we are done */
691 static struct key_vector
*collapse(struct trie
*t
,
692 struct key_vector
*oldtnode
)
694 struct key_vector
*n
, *tp
;
697 /* scan the tnode looking for that one child that might still exist */
698 for (n
= NULL
, i
= child_length(oldtnode
); !n
&& i
;)
699 n
= get_child(oldtnode
, --i
);
701 /* compress one level */
702 tp
= node_parent(oldtnode
);
703 put_child_root(tp
, oldtnode
->key
, n
);
704 node_set_parent(n
, tp
);
712 static unsigned char update_suffix(struct key_vector
*tn
)
714 unsigned char slen
= tn
->pos
;
715 unsigned long stride
, i
;
716 unsigned char slen_max
;
718 /* only vector 0 can have a suffix length greater than or equal to
719 * tn->pos + tn->bits, the second highest node will have a suffix
720 * length at most of tn->pos + tn->bits - 1
722 slen_max
= min_t(unsigned char, tn
->pos
+ tn
->bits
- 1, tn
->slen
);
724 /* search though the list of children looking for nodes that might
725 * have a suffix greater than the one we currently have. This is
726 * why we start with a stride of 2 since a stride of 1 would
727 * represent the nodes with suffix length equal to tn->pos
729 for (i
= 0, stride
= 0x2ul
; i
< child_length(tn
); i
+= stride
) {
730 struct key_vector
*n
= get_child(tn
, i
);
732 if (!n
|| (n
->slen
<= slen
))
735 /* update stride and slen based on new value */
736 stride
<<= (n
->slen
- slen
);
740 /* stop searching if we have hit the maximum possible value */
741 if (slen
>= slen_max
)
750 /* From "Implementing a dynamic compressed trie" by Stefan Nilsson of
751 * the Helsinki University of Technology and Matti Tikkanen of Nokia
752 * Telecommunications, page 6:
753 * "A node is doubled if the ratio of non-empty children to all
754 * children in the *doubled* node is at least 'high'."
756 * 'high' in this instance is the variable 'inflate_threshold'. It
757 * is expressed as a percentage, so we multiply it with
758 * child_length() and instead of multiplying by 2 (since the
759 * child array will be doubled by inflate()) and multiplying
760 * the left-hand side by 100 (to handle the percentage thing) we
761 * multiply the left-hand side by 50.
763 * The left-hand side may look a bit weird: child_length(tn)
764 * - tn->empty_children is of course the number of non-null children
765 * in the current node. tn->full_children is the number of "full"
766 * children, that is non-null tnodes with a skip value of 0.
767 * All of those will be doubled in the resulting inflated tnode, so
768 * we just count them one extra time here.
770 * A clearer way to write this would be:
772 * to_be_doubled = tn->full_children;
773 * not_to_be_doubled = child_length(tn) - tn->empty_children -
776 * new_child_length = child_length(tn) * 2;
778 * new_fill_factor = 100 * (not_to_be_doubled + 2*to_be_doubled) /
780 * if (new_fill_factor >= inflate_threshold)
782 * ...and so on, tho it would mess up the while () loop.
785 * 100 * (not_to_be_doubled + 2*to_be_doubled) / new_child_length >=
789 * 100 * (not_to_be_doubled + 2*to_be_doubled) >=
790 * inflate_threshold * new_child_length
792 * expand not_to_be_doubled and to_be_doubled, and shorten:
793 * 100 * (child_length(tn) - tn->empty_children +
794 * tn->full_children) >= inflate_threshold * new_child_length
796 * expand new_child_length:
797 * 100 * (child_length(tn) - tn->empty_children +
798 * tn->full_children) >=
799 * inflate_threshold * child_length(tn) * 2
802 * 50 * (tn->full_children + child_length(tn) -
803 * tn->empty_children) >= inflate_threshold *
807 static inline bool should_inflate(struct key_vector
*tp
, struct key_vector
*tn
)
809 unsigned long used
= child_length(tn
);
810 unsigned long threshold
= used
;
812 /* Keep root node larger */
813 threshold
*= IS_TRIE(tp
) ? inflate_threshold_root
: inflate_threshold
;
814 used
-= tn_info(tn
)->empty_children
;
815 used
+= tn_info(tn
)->full_children
;
817 /* if bits == KEYLENGTH then pos = 0, and will fail below */
819 return (used
> 1) && tn
->pos
&& ((50 * used
) >= threshold
);
822 static inline bool should_halve(struct key_vector
*tp
, struct key_vector
*tn
)
824 unsigned long used
= child_length(tn
);
825 unsigned long threshold
= used
;
827 /* Keep root node larger */
828 threshold
*= IS_TRIE(tp
) ? halve_threshold_root
: halve_threshold
;
829 used
-= tn_info(tn
)->empty_children
;
831 /* if bits == KEYLENGTH then used = 100% on wrap, and will fail below */
833 return (used
> 1) && (tn
->bits
> 1) && ((100 * used
) < threshold
);
836 static inline bool should_collapse(struct key_vector
*tn
)
838 unsigned long used
= child_length(tn
);
840 used
-= tn_info(tn
)->empty_children
;
842 /* account for bits == KEYLENGTH case */
843 if ((tn
->bits
== KEYLENGTH
) && tn_info(tn
)->full_children
)
846 /* One child or none, time to drop us from the trie */
851 static struct key_vector
*resize(struct trie
*t
, struct key_vector
*tn
)
853 #ifdef CONFIG_IP_FIB_TRIE_STATS
854 struct trie_use_stats __percpu
*stats
= t
->stats
;
856 struct key_vector
*tp
= node_parent(tn
);
857 unsigned long cindex
= get_index(tn
->key
, tp
);
858 int max_work
= MAX_WORK
;
860 pr_debug("In tnode_resize %p inflate_threshold=%d threshold=%d\n",
861 tn
, inflate_threshold
, halve_threshold
);
863 /* track the tnode via the pointer from the parent instead of
864 * doing it ourselves. This way we can let RCU fully do its
865 * thing without us interfering
867 BUG_ON(tn
!= get_child(tp
, cindex
));
869 /* Double as long as the resulting node has a number of
870 * nonempty nodes that are above the threshold.
872 while (should_inflate(tp
, tn
) && max_work
) {
875 #ifdef CONFIG_IP_FIB_TRIE_STATS
876 this_cpu_inc(stats
->resize_node_skipped
);
882 tn
= get_child(tp
, cindex
);
885 /* update parent in case inflate failed */
886 tp
= node_parent(tn
);
888 /* Return if at least one inflate is run */
889 if (max_work
!= MAX_WORK
)
892 /* Halve as long as the number of empty children in this
893 * node is above threshold.
895 while (should_halve(tp
, tn
) && max_work
) {
898 #ifdef CONFIG_IP_FIB_TRIE_STATS
899 this_cpu_inc(stats
->resize_node_skipped
);
905 tn
= get_child(tp
, cindex
);
908 /* Only one child remains */
909 if (should_collapse(tn
))
910 return collapse(t
, tn
);
912 /* update parent in case halve failed */
913 return node_parent(tn
);
916 static void node_pull_suffix(struct key_vector
*tn
, unsigned char slen
)
918 unsigned char node_slen
= tn
->slen
;
920 while ((node_slen
> tn
->pos
) && (node_slen
> slen
)) {
921 slen
= update_suffix(tn
);
922 if (node_slen
== slen
)
925 tn
= node_parent(tn
);
926 node_slen
= tn
->slen
;
930 static void node_push_suffix(struct key_vector
*tn
, unsigned char slen
)
932 while (tn
->slen
< slen
) {
934 tn
= node_parent(tn
);
938 /* rcu_read_lock needs to be hold by caller from readside */
939 static struct key_vector
*fib_find_node(struct trie
*t
,
940 struct key_vector
**tp
, u32 key
)
942 struct key_vector
*pn
, *n
= t
->kv
;
943 unsigned long index
= 0;
947 n
= get_child_rcu(n
, index
);
952 index
= get_cindex(key
, n
);
954 /* This bit of code is a bit tricky but it combines multiple
955 * checks into a single check. The prefix consists of the
956 * prefix plus zeros for the bits in the cindex. The index
957 * is the difference between the key and this value. From
958 * this we can actually derive several pieces of data.
959 * if (index >= (1ul << bits))
960 * we have a mismatch in skip bits and failed
962 * we know the value is cindex
964 * This check is safe even if bits == KEYLENGTH due to the
965 * fact that we can only allocate a node with 32 bits if a
966 * long is greater than 32 bits.
968 if (index
>= (1ul << n
->bits
)) {
973 /* keep searching until we find a perfect match leaf or NULL */
974 } while (IS_TNODE(n
));
981 /* Return the first fib alias matching TOS with
982 * priority less than or equal to PRIO.
984 static struct fib_alias
*fib_find_alias(struct hlist_head
*fah
, u8 slen
,
985 u8 tos
, u32 prio
, u32 tb_id
)
987 struct fib_alias
*fa
;
992 hlist_for_each_entry(fa
, fah
, fa_list
) {
993 if (fa
->fa_slen
< slen
)
995 if (fa
->fa_slen
!= slen
)
997 if (fa
->tb_id
> tb_id
)
999 if (fa
->tb_id
!= tb_id
)
1001 if (fa
->fa_tos
> tos
)
1003 if (fa
->fa_info
->fib_priority
>= prio
|| fa
->fa_tos
< tos
)
1010 static void trie_rebalance(struct trie
*t
, struct key_vector
*tn
)
1012 while (!IS_TRIE(tn
))
1016 static int fib_insert_node(struct trie
*t
, struct key_vector
*tp
,
1017 struct fib_alias
*new, t_key key
)
1019 struct key_vector
*n
, *l
;
1021 l
= leaf_new(key
, new);
1025 /* retrieve child from parent node */
1026 n
= get_child(tp
, get_index(key
, tp
));
1028 /* Case 2: n is a LEAF or a TNODE and the key doesn't match.
1030 * Add a new tnode here
1031 * first tnode need some special handling
1032 * leaves us in position for handling as case 3
1035 struct key_vector
*tn
;
1037 tn
= tnode_new(key
, __fls(key
^ n
->key
), 1);
1041 /* initialize routes out of node */
1042 NODE_INIT_PARENT(tn
, tp
);
1043 put_child(tn
, get_index(key
, tn
) ^ 1, n
);
1045 /* start adding routes into the node */
1046 put_child_root(tp
, key
, tn
);
1047 node_set_parent(n
, tn
);
1049 /* parent now has a NULL spot where the leaf can go */
1053 /* Case 3: n is NULL, and will just insert a new leaf */
1054 node_push_suffix(tp
, new->fa_slen
);
1055 NODE_INIT_PARENT(l
, tp
);
1056 put_child_root(tp
, key
, l
);
1057 trie_rebalance(t
, tp
);
1066 static int fib_insert_alias(struct trie
*t
, struct key_vector
*tp
,
1067 struct key_vector
*l
, struct fib_alias
*new,
1068 struct fib_alias
*fa
, t_key key
)
1071 return fib_insert_node(t
, tp
, new, key
);
1074 hlist_add_before_rcu(&new->fa_list
, &fa
->fa_list
);
1076 struct fib_alias
*last
;
1078 hlist_for_each_entry(last
, &l
->leaf
, fa_list
) {
1079 if (new->fa_slen
< last
->fa_slen
)
1081 if ((new->fa_slen
== last
->fa_slen
) &&
1082 (new->tb_id
> last
->tb_id
))
1088 hlist_add_behind_rcu(&new->fa_list
, &fa
->fa_list
);
1090 hlist_add_head_rcu(&new->fa_list
, &l
->leaf
);
1093 /* if we added to the tail node then we need to update slen */
1094 if (l
->slen
< new->fa_slen
) {
1095 l
->slen
= new->fa_slen
;
1096 node_push_suffix(tp
, new->fa_slen
);
1102 /* Caller must hold RTNL. */
1103 int fib_table_insert(struct net
*net
, struct fib_table
*tb
,
1104 struct fib_config
*cfg
)
1106 enum fib_event_type event
= FIB_EVENT_ENTRY_ADD
;
1107 struct trie
*t
= (struct trie
*)tb
->tb_data
;
1108 struct fib_alias
*fa
, *new_fa
;
1109 struct key_vector
*l
, *tp
;
1110 u16 nlflags
= NLM_F_EXCL
;
1111 struct fib_info
*fi
;
1112 u8 plen
= cfg
->fc_dst_len
;
1113 u8 slen
= KEYLENGTH
- plen
;
1114 u8 tos
= cfg
->fc_tos
;
1118 if (plen
> KEYLENGTH
)
1121 key
= ntohl(cfg
->fc_dst
);
1123 pr_debug("Insert table=%u %08x/%d\n", tb
->tb_id
, key
, plen
);
1125 if ((plen
< KEYLENGTH
) && (key
<< plen
))
1128 fi
= fib_create_info(cfg
);
1134 l
= fib_find_node(t
, &tp
, key
);
1135 fa
= l
? fib_find_alias(&l
->leaf
, slen
, tos
, fi
->fib_priority
,
1138 /* Now fa, if non-NULL, points to the first fib alias
1139 * with the same keys [prefix,tos,priority], if such key already
1140 * exists or to the node before which we will insert new one.
1142 * If fa is NULL, we will need to allocate a new one and
1143 * insert to the tail of the section matching the suffix length
1147 if (fa
&& fa
->fa_tos
== tos
&&
1148 fa
->fa_info
->fib_priority
== fi
->fib_priority
) {
1149 struct fib_alias
*fa_first
, *fa_match
;
1152 if (cfg
->fc_nlflags
& NLM_F_EXCL
)
1155 nlflags
&= ~NLM_F_EXCL
;
1158 * 1. Find exact match for type, scope, fib_info to avoid
1160 * 2. Find next 'fa' (or head), NLM_F_APPEND inserts before it
1164 hlist_for_each_entry_from(fa
, fa_list
) {
1165 if ((fa
->fa_slen
!= slen
) ||
1166 (fa
->tb_id
!= tb
->tb_id
) ||
1167 (fa
->fa_tos
!= tos
))
1169 if (fa
->fa_info
->fib_priority
!= fi
->fib_priority
)
1171 if (fa
->fa_type
== cfg
->fc_type
&&
1172 fa
->fa_info
== fi
) {
1178 if (cfg
->fc_nlflags
& NLM_F_REPLACE
) {
1179 struct fib_info
*fi_drop
;
1182 nlflags
|= NLM_F_REPLACE
;
1190 new_fa
= kmem_cache_alloc(fn_alias_kmem
, GFP_KERNEL
);
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 state
= fa
->fa_state
;
1199 new_fa
->fa_state
= state
& ~FA_S_ACCESSED
;
1200 new_fa
->fa_slen
= fa
->fa_slen
;
1201 new_fa
->tb_id
= tb
->tb_id
;
1202 new_fa
->fa_default
= -1;
1204 call_fib_entry_notifiers(net
, FIB_EVENT_ENTRY_REPLACE
,
1206 new_fa
->fa_tos
, cfg
->fc_type
,
1208 rtmsg_fib(RTM_NEWROUTE
, htonl(key
), new_fa
, plen
,
1209 tb
->tb_id
, &cfg
->fc_nlinfo
, nlflags
);
1211 hlist_replace_rcu(&fa
->fa_list
, &new_fa
->fa_list
);
1213 alias_free_mem_rcu(fa
);
1215 fib_release_info(fi_drop
);
1216 if (state
& FA_S_ACCESSED
)
1217 rt_cache_flush(cfg
->fc_nlinfo
.nl_net
);
1221 /* Error if we find a perfect match which
1222 * uses the same scope, type, and nexthop
1228 if (cfg
->fc_nlflags
& NLM_F_APPEND
) {
1229 event
= FIB_EVENT_ENTRY_APPEND
;
1230 nlflags
|= NLM_F_APPEND
;
1236 if (!(cfg
->fc_nlflags
& NLM_F_CREATE
))
1239 nlflags
|= NLM_F_CREATE
;
1241 new_fa
= kmem_cache_alloc(fn_alias_kmem
, GFP_KERNEL
);
1245 new_fa
->fa_info
= fi
;
1246 new_fa
->fa_tos
= tos
;
1247 new_fa
->fa_type
= cfg
->fc_type
;
1248 new_fa
->fa_state
= 0;
1249 new_fa
->fa_slen
= slen
;
1250 new_fa
->tb_id
= tb
->tb_id
;
1251 new_fa
->fa_default
= -1;
1253 /* Insert new entry to the list. */
1254 err
= fib_insert_alias(t
, tp
, l
, new_fa
, fa
, key
);
1256 goto out_free_new_fa
;
1259 tb
->tb_num_default
++;
1261 rt_cache_flush(cfg
->fc_nlinfo
.nl_net
);
1262 call_fib_entry_notifiers(net
, event
, key
, plen
, fi
, tos
, cfg
->fc_type
,
1264 rtmsg_fib(RTM_NEWROUTE
, htonl(key
), new_fa
, plen
, new_fa
->tb_id
,
1265 &cfg
->fc_nlinfo
, nlflags
);
1270 kmem_cache_free(fn_alias_kmem
, new_fa
);
1272 fib_release_info(fi
);
1277 static inline t_key
prefix_mismatch(t_key key
, struct key_vector
*n
)
1279 t_key prefix
= n
->key
;
1281 return (key
^ prefix
) & (prefix
| -prefix
);
1284 /* should be called with rcu_read_lock */
1285 int fib_table_lookup(struct fib_table
*tb
, const struct flowi4
*flp
,
1286 struct fib_result
*res
, int fib_flags
)
1288 struct trie
*t
= (struct trie
*) tb
->tb_data
;
1289 #ifdef CONFIG_IP_FIB_TRIE_STATS
1290 struct trie_use_stats __percpu
*stats
= t
->stats
;
1292 const t_key key
= ntohl(flp
->daddr
);
1293 struct key_vector
*n
, *pn
;
1294 struct fib_alias
*fa
;
1295 unsigned long index
;
1298 trace_fib_table_lookup(tb
->tb_id
, flp
);
1303 n
= get_child_rcu(pn
, cindex
);
1307 #ifdef CONFIG_IP_FIB_TRIE_STATS
1308 this_cpu_inc(stats
->gets
);
1311 /* Step 1: Travel to the longest prefix match in the trie */
1313 index
= get_cindex(key
, n
);
1315 /* This bit of code is a bit tricky but it combines multiple
1316 * checks into a single check. The prefix consists of the
1317 * prefix plus zeros for the "bits" in the prefix. The index
1318 * is the difference between the key and this value. From
1319 * this we can actually derive several pieces of data.
1320 * if (index >= (1ul << bits))
1321 * we have a mismatch in skip bits and failed
1323 * we know the value is cindex
1325 * This check is safe even if bits == KEYLENGTH due to the
1326 * fact that we can only allocate a node with 32 bits if a
1327 * long is greater than 32 bits.
1329 if (index
>= (1ul << n
->bits
))
1332 /* we have found a leaf. Prefixes have already been compared */
1336 /* only record pn and cindex if we are going to be chopping
1337 * bits later. Otherwise we are just wasting cycles.
1339 if (n
->slen
> n
->pos
) {
1344 n
= get_child_rcu(n
, index
);
1349 /* Step 2: Sort out leaves and begin backtracing for longest prefix */
1351 /* record the pointer where our next node pointer is stored */
1352 struct key_vector __rcu
**cptr
= n
->tnode
;
1354 /* This test verifies that none of the bits that differ
1355 * between the key and the prefix exist in the region of
1356 * the lsb and higher in the prefix.
1358 if (unlikely(prefix_mismatch(key
, n
)) || (n
->slen
== n
->pos
))
1361 /* exit out and process leaf */
1362 if (unlikely(IS_LEAF(n
)))
1365 /* Don't bother recording parent info. Since we are in
1366 * prefix match mode we will have to come back to wherever
1367 * we started this traversal anyway
1370 while ((n
= rcu_dereference(*cptr
)) == NULL
) {
1372 #ifdef CONFIG_IP_FIB_TRIE_STATS
1374 this_cpu_inc(stats
->null_node_hit
);
1376 /* If we are at cindex 0 there are no more bits for
1377 * us to strip at this level so we must ascend back
1378 * up one level to see if there are any more bits to
1379 * be stripped there.
1382 t_key pkey
= pn
->key
;
1384 /* If we don't have a parent then there is
1385 * nothing for us to do as we do not have any
1386 * further nodes to parse.
1390 #ifdef CONFIG_IP_FIB_TRIE_STATS
1391 this_cpu_inc(stats
->backtrack
);
1393 /* Get Child's index */
1394 pn
= node_parent_rcu(pn
);
1395 cindex
= get_index(pkey
, pn
);
1398 /* strip the least significant bit from the cindex */
1399 cindex
&= cindex
- 1;
1401 /* grab pointer for next child node */
1402 cptr
= &pn
->tnode
[cindex
];
1407 /* this line carries forward the xor from earlier in the function */
1408 index
= key
^ n
->key
;
1410 /* Step 3: Process the leaf, if that fails fall back to backtracing */
1411 hlist_for_each_entry_rcu(fa
, &n
->leaf
, fa_list
) {
1412 struct fib_info
*fi
= fa
->fa_info
;
1415 if ((BITS_PER_LONG
> KEYLENGTH
) || (fa
->fa_slen
< KEYLENGTH
)) {
1416 if (index
>= (1ul << fa
->fa_slen
))
1419 if (fa
->fa_tos
&& fa
->fa_tos
!= flp
->flowi4_tos
)
1423 if (fa
->fa_info
->fib_scope
< flp
->flowi4_scope
)
1425 fib_alias_accessed(fa
);
1426 err
= fib_props
[fa
->fa_type
].error
;
1427 if (unlikely(err
< 0)) {
1428 #ifdef CONFIG_IP_FIB_TRIE_STATS
1429 this_cpu_inc(stats
->semantic_match_passed
);
1433 if (fi
->fib_flags
& RTNH_F_DEAD
)
1435 for (nhsel
= 0; nhsel
< fi
->fib_nhs
; nhsel
++) {
1436 const struct fib_nh
*nh
= &fi
->fib_nh
[nhsel
];
1437 struct in_device
*in_dev
= __in_dev_get_rcu(nh
->nh_dev
);
1439 if (nh
->nh_flags
& RTNH_F_DEAD
)
1442 IN_DEV_IGNORE_ROUTES_WITH_LINKDOWN(in_dev
) &&
1443 nh
->nh_flags
& RTNH_F_LINKDOWN
&&
1444 !(fib_flags
& FIB_LOOKUP_IGNORE_LINKSTATE
))
1446 if (!(flp
->flowi4_flags
& FLOWI_FLAG_SKIP_NH_OIF
)) {
1447 if (flp
->flowi4_oif
&&
1448 flp
->flowi4_oif
!= nh
->nh_oif
)
1452 if (!(fib_flags
& FIB_LOOKUP_NOREF
))
1453 atomic_inc(&fi
->fib_clntref
);
1455 res
->prefixlen
= KEYLENGTH
- fa
->fa_slen
;
1456 res
->nh_sel
= nhsel
;
1457 res
->type
= fa
->fa_type
;
1458 res
->scope
= fi
->fib_scope
;
1461 res
->fa_head
= &n
->leaf
;
1462 #ifdef CONFIG_IP_FIB_TRIE_STATS
1463 this_cpu_inc(stats
->semantic_match_passed
);
1465 trace_fib_table_lookup_nh(nh
);
1470 #ifdef CONFIG_IP_FIB_TRIE_STATS
1471 this_cpu_inc(stats
->semantic_match_miss
);
1475 EXPORT_SYMBOL_GPL(fib_table_lookup
);
1477 static void fib_remove_alias(struct trie
*t
, struct key_vector
*tp
,
1478 struct key_vector
*l
, struct fib_alias
*old
)
1480 /* record the location of the previous list_info entry */
1481 struct hlist_node
**pprev
= old
->fa_list
.pprev
;
1482 struct fib_alias
*fa
= hlist_entry(pprev
, typeof(*fa
), fa_list
.next
);
1484 /* remove the fib_alias from the list */
1485 hlist_del_rcu(&old
->fa_list
);
1487 /* if we emptied the list this leaf will be freed and we can sort
1488 * out parent suffix lengths as a part of trie_rebalance
1490 if (hlist_empty(&l
->leaf
)) {
1491 if (tp
->slen
== l
->slen
)
1492 node_pull_suffix(tp
, tp
->pos
);
1493 put_child_root(tp
, l
->key
, NULL
);
1495 trie_rebalance(t
, tp
);
1499 /* only access fa if it is pointing at the last valid hlist_node */
1503 /* update the trie with the latest suffix length */
1504 l
->slen
= fa
->fa_slen
;
1505 node_pull_suffix(tp
, fa
->fa_slen
);
1508 /* Caller must hold RTNL. */
1509 int fib_table_delete(struct net
*net
, struct fib_table
*tb
,
1510 struct fib_config
*cfg
)
1512 struct trie
*t
= (struct trie
*) tb
->tb_data
;
1513 struct fib_alias
*fa
, *fa_to_delete
;
1514 struct key_vector
*l
, *tp
;
1515 u8 plen
= cfg
->fc_dst_len
;
1516 u8 slen
= KEYLENGTH
- plen
;
1517 u8 tos
= cfg
->fc_tos
;
1520 if (plen
> KEYLENGTH
)
1523 key
= ntohl(cfg
->fc_dst
);
1525 if ((plen
< KEYLENGTH
) && (key
<< plen
))
1528 l
= fib_find_node(t
, &tp
, key
);
1532 fa
= fib_find_alias(&l
->leaf
, slen
, tos
, 0, tb
->tb_id
);
1536 pr_debug("Deleting %08x/%d tos=%d t=%p\n", key
, plen
, tos
, t
);
1538 fa_to_delete
= NULL
;
1539 hlist_for_each_entry_from(fa
, fa_list
) {
1540 struct fib_info
*fi
= fa
->fa_info
;
1542 if ((fa
->fa_slen
!= slen
) ||
1543 (fa
->tb_id
!= tb
->tb_id
) ||
1544 (fa
->fa_tos
!= tos
))
1547 if ((!cfg
->fc_type
|| fa
->fa_type
== cfg
->fc_type
) &&
1548 (cfg
->fc_scope
== RT_SCOPE_NOWHERE
||
1549 fa
->fa_info
->fib_scope
== cfg
->fc_scope
) &&
1550 (!cfg
->fc_prefsrc
||
1551 fi
->fib_prefsrc
== cfg
->fc_prefsrc
) &&
1552 (!cfg
->fc_protocol
||
1553 fi
->fib_protocol
== cfg
->fc_protocol
) &&
1554 fib_nh_match(cfg
, fi
) == 0) {
1563 call_fib_entry_notifiers(net
, FIB_EVENT_ENTRY_DEL
, key
, plen
,
1564 fa_to_delete
->fa_info
, tos
,
1565 fa_to_delete
->fa_type
, tb
->tb_id
);
1566 rtmsg_fib(RTM_DELROUTE
, htonl(key
), fa_to_delete
, plen
, tb
->tb_id
,
1567 &cfg
->fc_nlinfo
, 0);
1570 tb
->tb_num_default
--;
1572 fib_remove_alias(t
, tp
, l
, fa_to_delete
);
1574 if (fa_to_delete
->fa_state
& FA_S_ACCESSED
)
1575 rt_cache_flush(cfg
->fc_nlinfo
.nl_net
);
1577 fib_release_info(fa_to_delete
->fa_info
);
1578 alias_free_mem_rcu(fa_to_delete
);
1582 /* Scan for the next leaf starting at the provided key value */
1583 static struct key_vector
*leaf_walk_rcu(struct key_vector
**tn
, t_key key
)
1585 struct key_vector
*pn
, *n
= *tn
;
1586 unsigned long cindex
;
1588 /* this loop is meant to try and find the key in the trie */
1590 /* record parent and next child index */
1592 cindex
= (key
> pn
->key
) ? get_index(key
, pn
) : 0;
1594 if (cindex
>> pn
->bits
)
1597 /* descend into the next child */
1598 n
= get_child_rcu(pn
, cindex
++);
1602 /* guarantee forward progress on the keys */
1603 if (IS_LEAF(n
) && (n
->key
>= key
))
1605 } while (IS_TNODE(n
));
1607 /* this loop will search for the next leaf with a greater key */
1608 while (!IS_TRIE(pn
)) {
1609 /* if we exhausted the parent node we will need to climb */
1610 if (cindex
>= (1ul << pn
->bits
)) {
1611 t_key pkey
= pn
->key
;
1613 pn
= node_parent_rcu(pn
);
1614 cindex
= get_index(pkey
, pn
) + 1;
1618 /* grab the next available node */
1619 n
= get_child_rcu(pn
, cindex
++);
1623 /* no need to compare keys since we bumped the index */
1627 /* Rescan start scanning in new node */
1633 return NULL
; /* Root of trie */
1635 /* if we are at the limit for keys just return NULL for the tnode */
1640 static void fib_trie_free(struct fib_table
*tb
)
1642 struct trie
*t
= (struct trie
*)tb
->tb_data
;
1643 struct key_vector
*pn
= t
->kv
;
1644 unsigned long cindex
= 1;
1645 struct hlist_node
*tmp
;
1646 struct fib_alias
*fa
;
1648 /* walk trie in reverse order and free everything */
1650 struct key_vector
*n
;
1653 t_key pkey
= pn
->key
;
1659 pn
= node_parent(pn
);
1661 /* drop emptied tnode */
1662 put_child_root(pn
, n
->key
, NULL
);
1665 cindex
= get_index(pkey
, pn
);
1670 /* grab the next available node */
1671 n
= get_child(pn
, cindex
);
1676 /* record pn and cindex for leaf walking */
1678 cindex
= 1ul << n
->bits
;
1683 hlist_for_each_entry_safe(fa
, tmp
, &n
->leaf
, fa_list
) {
1684 hlist_del_rcu(&fa
->fa_list
);
1685 alias_free_mem_rcu(fa
);
1688 put_child_root(pn
, n
->key
, NULL
);
1692 #ifdef CONFIG_IP_FIB_TRIE_STATS
1693 free_percpu(t
->stats
);
1698 struct fib_table
*fib_trie_unmerge(struct fib_table
*oldtb
)
1700 struct trie
*ot
= (struct trie
*)oldtb
->tb_data
;
1701 struct key_vector
*l
, *tp
= ot
->kv
;
1702 struct fib_table
*local_tb
;
1703 struct fib_alias
*fa
;
1707 if (oldtb
->tb_data
== oldtb
->__data
)
1710 local_tb
= fib_trie_table(RT_TABLE_LOCAL
, NULL
);
1714 lt
= (struct trie
*)local_tb
->tb_data
;
1716 while ((l
= leaf_walk_rcu(&tp
, key
)) != NULL
) {
1717 struct key_vector
*local_l
= NULL
, *local_tp
;
1719 hlist_for_each_entry_rcu(fa
, &l
->leaf
, fa_list
) {
1720 struct fib_alias
*new_fa
;
1722 if (local_tb
->tb_id
!= fa
->tb_id
)
1725 /* clone fa for new local table */
1726 new_fa
= kmem_cache_alloc(fn_alias_kmem
, GFP_KERNEL
);
1730 memcpy(new_fa
, fa
, sizeof(*fa
));
1732 /* insert clone into table */
1734 local_l
= fib_find_node(lt
, &local_tp
, l
->key
);
1736 if (fib_insert_alias(lt
, local_tp
, local_l
, new_fa
,
1738 kmem_cache_free(fn_alias_kmem
, new_fa
);
1743 /* stop loop if key wrapped back to 0 */
1751 fib_trie_free(local_tb
);
1756 /* Caller must hold RTNL */
1757 void fib_table_flush_external(struct fib_table
*tb
)
1759 struct trie
*t
= (struct trie
*)tb
->tb_data
;
1760 struct key_vector
*pn
= t
->kv
;
1761 unsigned long cindex
= 1;
1762 struct hlist_node
*tmp
;
1763 struct fib_alias
*fa
;
1765 /* walk trie in reverse order */
1767 unsigned char slen
= 0;
1768 struct key_vector
*n
;
1771 t_key pkey
= pn
->key
;
1773 /* cannot resize the trie vector */
1777 /* update the suffix to address pulled leaves */
1778 if (pn
->slen
> pn
->pos
)
1781 /* resize completed node */
1783 cindex
= get_index(pkey
, pn
);
1788 /* grab the next available node */
1789 n
= get_child(pn
, cindex
);
1794 /* record pn and cindex for leaf walking */
1796 cindex
= 1ul << n
->bits
;
1801 hlist_for_each_entry_safe(fa
, tmp
, &n
->leaf
, fa_list
) {
1802 /* if alias was cloned to local then we just
1803 * need to remove the local copy from main
1805 if (tb
->tb_id
!= fa
->tb_id
) {
1806 hlist_del_rcu(&fa
->fa_list
);
1807 alias_free_mem_rcu(fa
);
1811 /* record local slen */
1815 /* update leaf slen */
1818 if (hlist_empty(&n
->leaf
)) {
1819 put_child_root(pn
, n
->key
, NULL
);
1825 /* Caller must hold RTNL. */
1826 int fib_table_flush(struct net
*net
, struct fib_table
*tb
)
1828 struct trie
*t
= (struct trie
*)tb
->tb_data
;
1829 struct key_vector
*pn
= t
->kv
;
1830 unsigned long cindex
= 1;
1831 struct hlist_node
*tmp
;
1832 struct fib_alias
*fa
;
1835 /* walk trie in reverse order */
1837 unsigned char slen
= 0;
1838 struct key_vector
*n
;
1841 t_key pkey
= pn
->key
;
1843 /* cannot resize the trie vector */
1847 /* update the suffix to address pulled leaves */
1848 if (pn
->slen
> pn
->pos
)
1851 /* resize completed node */
1853 cindex
= get_index(pkey
, pn
);
1858 /* grab the next available node */
1859 n
= get_child(pn
, cindex
);
1864 /* record pn and cindex for leaf walking */
1866 cindex
= 1ul << n
->bits
;
1871 hlist_for_each_entry_safe(fa
, tmp
, &n
->leaf
, fa_list
) {
1872 struct fib_info
*fi
= fa
->fa_info
;
1874 if (!fi
|| !(fi
->fib_flags
& RTNH_F_DEAD
) ||
1875 tb
->tb_id
!= fa
->tb_id
) {
1880 call_fib_entry_notifiers(net
, FIB_EVENT_ENTRY_DEL
,
1882 KEYLENGTH
- fa
->fa_slen
,
1883 fi
, fa
->fa_tos
, fa
->fa_type
,
1885 hlist_del_rcu(&fa
->fa_list
);
1886 fib_release_info(fa
->fa_info
);
1887 alias_free_mem_rcu(fa
);
1891 /* update leaf slen */
1894 if (hlist_empty(&n
->leaf
)) {
1895 put_child_root(pn
, n
->key
, NULL
);
1900 pr_debug("trie_flush found=%d\n", found
);
1904 static void fib_leaf_notify(struct net
*net
, struct key_vector
*l
,
1905 struct fib_table
*tb
, struct notifier_block
*nb
)
1907 struct fib_alias
*fa
;
1909 hlist_for_each_entry_rcu(fa
, &l
->leaf
, fa_list
) {
1910 struct fib_info
*fi
= fa
->fa_info
;
1915 /* local and main table can share the same trie,
1916 * so don't notify twice for the same entry.
1918 if (tb
->tb_id
!= fa
->tb_id
)
1921 call_fib_entry_notifier(nb
, net
, FIB_EVENT_ENTRY_ADD
, l
->key
,
1922 KEYLENGTH
- fa
->fa_slen
, fi
, fa
->fa_tos
,
1923 fa
->fa_type
, fa
->tb_id
);
1927 static void fib_table_notify(struct net
*net
, struct fib_table
*tb
,
1928 struct notifier_block
*nb
)
1930 struct trie
*t
= (struct trie
*)tb
->tb_data
;
1931 struct key_vector
*l
, *tp
= t
->kv
;
1934 while ((l
= leaf_walk_rcu(&tp
, key
)) != NULL
) {
1935 fib_leaf_notify(net
, l
, tb
, nb
);
1938 /* stop in case of wrap around */
1944 void fib_notify(struct net
*net
, struct notifier_block
*nb
)
1948 for (h
= 0; h
< FIB_TABLE_HASHSZ
; h
++) {
1949 struct hlist_head
*head
= &net
->ipv4
.fib_table_hash
[h
];
1950 struct fib_table
*tb
;
1952 hlist_for_each_entry_rcu(tb
, head
, tb_hlist
)
1953 fib_table_notify(net
, tb
, nb
);
1957 static void __trie_free_rcu(struct rcu_head
*head
)
1959 struct fib_table
*tb
= container_of(head
, struct fib_table
, rcu
);
1960 #ifdef CONFIG_IP_FIB_TRIE_STATS
1961 struct trie
*t
= (struct trie
*)tb
->tb_data
;
1963 if (tb
->tb_data
== tb
->__data
)
1964 free_percpu(t
->stats
);
1965 #endif /* CONFIG_IP_FIB_TRIE_STATS */
1969 void fib_free_table(struct fib_table
*tb
)
1971 call_rcu(&tb
->rcu
, __trie_free_rcu
);
1974 static int fn_trie_dump_leaf(struct key_vector
*l
, struct fib_table
*tb
,
1975 struct sk_buff
*skb
, struct netlink_callback
*cb
)
1977 __be32 xkey
= htonl(l
->key
);
1978 struct fib_alias
*fa
;
1984 /* rcu_read_lock is hold by caller */
1985 hlist_for_each_entry_rcu(fa
, &l
->leaf
, fa_list
) {
1991 if (tb
->tb_id
!= fa
->tb_id
) {
1996 if (fib_dump_info(skb
, NETLINK_CB(cb
->skb
).portid
,
2002 KEYLENGTH
- fa
->fa_slen
,
2004 fa
->fa_info
, NLM_F_MULTI
) < 0) {
2015 /* rcu_read_lock needs to be hold by caller from readside */
2016 int fib_table_dump(struct fib_table
*tb
, struct sk_buff
*skb
,
2017 struct netlink_callback
*cb
)
2019 struct trie
*t
= (struct trie
*)tb
->tb_data
;
2020 struct key_vector
*l
, *tp
= t
->kv
;
2021 /* Dump starting at last key.
2022 * Note: 0.0.0.0/0 (ie default) is first key.
2024 int count
= cb
->args
[2];
2025 t_key key
= cb
->args
[3];
2027 while ((l
= leaf_walk_rcu(&tp
, key
)) != NULL
) {
2028 if (fn_trie_dump_leaf(l
, tb
, skb
, cb
) < 0) {
2030 cb
->args
[2] = count
;
2037 memset(&cb
->args
[4], 0,
2038 sizeof(cb
->args
) - 4*sizeof(cb
->args
[0]));
2040 /* stop loop if key wrapped back to 0 */
2046 cb
->args
[2] = count
;
2051 void __init
fib_trie_init(void)
2053 fn_alias_kmem
= kmem_cache_create("ip_fib_alias",
2054 sizeof(struct fib_alias
),
2055 0, SLAB_PANIC
, NULL
);
2057 trie_leaf_kmem
= kmem_cache_create("ip_fib_trie",
2059 0, SLAB_PANIC
, NULL
);
2062 struct fib_table
*fib_trie_table(u32 id
, struct fib_table
*alias
)
2064 struct fib_table
*tb
;
2066 size_t sz
= sizeof(*tb
);
2069 sz
+= sizeof(struct trie
);
2071 tb
= kzalloc(sz
, GFP_KERNEL
);
2076 tb
->tb_num_default
= 0;
2077 tb
->tb_data
= (alias
? alias
->__data
: tb
->__data
);
2082 t
= (struct trie
*) tb
->tb_data
;
2083 t
->kv
[0].pos
= KEYLENGTH
;
2084 t
->kv
[0].slen
= KEYLENGTH
;
2085 #ifdef CONFIG_IP_FIB_TRIE_STATS
2086 t
->stats
= alloc_percpu(struct trie_use_stats
);
2096 #ifdef CONFIG_PROC_FS
2097 /* Depth first Trie walk iterator */
2098 struct fib_trie_iter
{
2099 struct seq_net_private p
;
2100 struct fib_table
*tb
;
2101 struct key_vector
*tnode
;
2106 static struct key_vector
*fib_trie_get_next(struct fib_trie_iter
*iter
)
2108 unsigned long cindex
= iter
->index
;
2109 struct key_vector
*pn
= iter
->tnode
;
2112 pr_debug("get_next iter={node=%p index=%d depth=%d}\n",
2113 iter
->tnode
, iter
->index
, iter
->depth
);
2115 while (!IS_TRIE(pn
)) {
2116 while (cindex
< child_length(pn
)) {
2117 struct key_vector
*n
= get_child_rcu(pn
, cindex
++);
2124 iter
->index
= cindex
;
2126 /* push down one level */
2135 /* Current node exhausted, pop back up */
2137 pn
= node_parent_rcu(pn
);
2138 cindex
= get_index(pkey
, pn
) + 1;
2142 /* record root node so further searches know we are done */
2149 static struct key_vector
*fib_trie_get_first(struct fib_trie_iter
*iter
,
2152 struct key_vector
*n
, *pn
;
2158 n
= rcu_dereference(pn
->tnode
[0]);
2175 static void trie_collect_stats(struct trie
*t
, struct trie_stat
*s
)
2177 struct key_vector
*n
;
2178 struct fib_trie_iter iter
;
2180 memset(s
, 0, sizeof(*s
));
2183 for (n
= fib_trie_get_first(&iter
, t
); n
; n
= fib_trie_get_next(&iter
)) {
2185 struct fib_alias
*fa
;
2188 s
->totdepth
+= iter
.depth
;
2189 if (iter
.depth
> s
->maxdepth
)
2190 s
->maxdepth
= iter
.depth
;
2192 hlist_for_each_entry_rcu(fa
, &n
->leaf
, fa_list
)
2196 if (n
->bits
< MAX_STAT_DEPTH
)
2197 s
->nodesizes
[n
->bits
]++;
2198 s
->nullpointers
+= tn_info(n
)->empty_children
;
2205 * This outputs /proc/net/fib_triestats
2207 static void trie_show_stats(struct seq_file
*seq
, struct trie_stat
*stat
)
2209 unsigned int i
, max
, pointers
, bytes
, avdepth
;
2212 avdepth
= stat
->totdepth
*100 / stat
->leaves
;
2216 seq_printf(seq
, "\tAver depth: %u.%02d\n",
2217 avdepth
/ 100, avdepth
% 100);
2218 seq_printf(seq
, "\tMax depth: %u\n", stat
->maxdepth
);
2220 seq_printf(seq
, "\tLeaves: %u\n", stat
->leaves
);
2221 bytes
= LEAF_SIZE
* stat
->leaves
;
2223 seq_printf(seq
, "\tPrefixes: %u\n", stat
->prefixes
);
2224 bytes
+= sizeof(struct fib_alias
) * stat
->prefixes
;
2226 seq_printf(seq
, "\tInternal nodes: %u\n\t", stat
->tnodes
);
2227 bytes
+= TNODE_SIZE(0) * stat
->tnodes
;
2229 max
= MAX_STAT_DEPTH
;
2230 while (max
> 0 && stat
->nodesizes
[max
-1] == 0)
2234 for (i
= 1; i
< max
; i
++)
2235 if (stat
->nodesizes
[i
] != 0) {
2236 seq_printf(seq
, " %u: %u", i
, stat
->nodesizes
[i
]);
2237 pointers
+= (1<<i
) * stat
->nodesizes
[i
];
2239 seq_putc(seq
, '\n');
2240 seq_printf(seq
, "\tPointers: %u\n", pointers
);
2242 bytes
+= sizeof(struct key_vector
*) * pointers
;
2243 seq_printf(seq
, "Null ptrs: %u\n", stat
->nullpointers
);
2244 seq_printf(seq
, "Total size: %u kB\n", (bytes
+ 1023) / 1024);
2247 #ifdef CONFIG_IP_FIB_TRIE_STATS
2248 static void trie_show_usage(struct seq_file
*seq
,
2249 const struct trie_use_stats __percpu
*stats
)
2251 struct trie_use_stats s
= { 0 };
2254 /* loop through all of the CPUs and gather up the stats */
2255 for_each_possible_cpu(cpu
) {
2256 const struct trie_use_stats
*pcpu
= per_cpu_ptr(stats
, cpu
);
2258 s
.gets
+= pcpu
->gets
;
2259 s
.backtrack
+= pcpu
->backtrack
;
2260 s
.semantic_match_passed
+= pcpu
->semantic_match_passed
;
2261 s
.semantic_match_miss
+= pcpu
->semantic_match_miss
;
2262 s
.null_node_hit
+= pcpu
->null_node_hit
;
2263 s
.resize_node_skipped
+= pcpu
->resize_node_skipped
;
2266 seq_printf(seq
, "\nCounters:\n---------\n");
2267 seq_printf(seq
, "gets = %u\n", s
.gets
);
2268 seq_printf(seq
, "backtracks = %u\n", s
.backtrack
);
2269 seq_printf(seq
, "semantic match passed = %u\n",
2270 s
.semantic_match_passed
);
2271 seq_printf(seq
, "semantic match miss = %u\n", s
.semantic_match_miss
);
2272 seq_printf(seq
, "null node hit= %u\n", s
.null_node_hit
);
2273 seq_printf(seq
, "skipped node resize = %u\n\n", s
.resize_node_skipped
);
2275 #endif /* CONFIG_IP_FIB_TRIE_STATS */
2277 static void fib_table_print(struct seq_file
*seq
, struct fib_table
*tb
)
2279 if (tb
->tb_id
== RT_TABLE_LOCAL
)
2280 seq_puts(seq
, "Local:\n");
2281 else if (tb
->tb_id
== RT_TABLE_MAIN
)
2282 seq_puts(seq
, "Main:\n");
2284 seq_printf(seq
, "Id %d:\n", tb
->tb_id
);
2288 static int fib_triestat_seq_show(struct seq_file
*seq
, void *v
)
2290 struct net
*net
= (struct net
*)seq
->private;
2294 "Basic info: size of leaf:"
2295 " %zd bytes, size of tnode: %zd bytes.\n",
2296 LEAF_SIZE
, TNODE_SIZE(0));
2298 for (h
= 0; h
< FIB_TABLE_HASHSZ
; h
++) {
2299 struct hlist_head
*head
= &net
->ipv4
.fib_table_hash
[h
];
2300 struct fib_table
*tb
;
2302 hlist_for_each_entry_rcu(tb
, head
, tb_hlist
) {
2303 struct trie
*t
= (struct trie
*) tb
->tb_data
;
2304 struct trie_stat stat
;
2309 fib_table_print(seq
, tb
);
2311 trie_collect_stats(t
, &stat
);
2312 trie_show_stats(seq
, &stat
);
2313 #ifdef CONFIG_IP_FIB_TRIE_STATS
2314 trie_show_usage(seq
, t
->stats
);
2322 static int fib_triestat_seq_open(struct inode
*inode
, struct file
*file
)
2324 return single_open_net(inode
, file
, fib_triestat_seq_show
);
2327 static const struct file_operations fib_triestat_fops
= {
2328 .owner
= THIS_MODULE
,
2329 .open
= fib_triestat_seq_open
,
2331 .llseek
= seq_lseek
,
2332 .release
= single_release_net
,
2335 static struct key_vector
*fib_trie_get_idx(struct seq_file
*seq
, loff_t pos
)
2337 struct fib_trie_iter
*iter
= seq
->private;
2338 struct net
*net
= seq_file_net(seq
);
2342 for (h
= 0; h
< FIB_TABLE_HASHSZ
; h
++) {
2343 struct hlist_head
*head
= &net
->ipv4
.fib_table_hash
[h
];
2344 struct fib_table
*tb
;
2346 hlist_for_each_entry_rcu(tb
, head
, tb_hlist
) {
2347 struct key_vector
*n
;
2349 for (n
= fib_trie_get_first(iter
,
2350 (struct trie
*) tb
->tb_data
);
2351 n
; n
= fib_trie_get_next(iter
))
2362 static void *fib_trie_seq_start(struct seq_file
*seq
, loff_t
*pos
)
2366 return fib_trie_get_idx(seq
, *pos
);
2369 static void *fib_trie_seq_next(struct seq_file
*seq
, void *v
, loff_t
*pos
)
2371 struct fib_trie_iter
*iter
= seq
->private;
2372 struct net
*net
= seq_file_net(seq
);
2373 struct fib_table
*tb
= iter
->tb
;
2374 struct hlist_node
*tb_node
;
2376 struct key_vector
*n
;
2379 /* next node in same table */
2380 n
= fib_trie_get_next(iter
);
2384 /* walk rest of this hash chain */
2385 h
= tb
->tb_id
& (FIB_TABLE_HASHSZ
- 1);
2386 while ((tb_node
= rcu_dereference(hlist_next_rcu(&tb
->tb_hlist
)))) {
2387 tb
= hlist_entry(tb_node
, struct fib_table
, tb_hlist
);
2388 n
= fib_trie_get_first(iter
, (struct trie
*) tb
->tb_data
);
2393 /* new hash chain */
2394 while (++h
< FIB_TABLE_HASHSZ
) {
2395 struct hlist_head
*head
= &net
->ipv4
.fib_table_hash
[h
];
2396 hlist_for_each_entry_rcu(tb
, head
, tb_hlist
) {
2397 n
= fib_trie_get_first(iter
, (struct trie
*) tb
->tb_data
);
2409 static void fib_trie_seq_stop(struct seq_file
*seq
, void *v
)
2415 static void seq_indent(struct seq_file
*seq
, int n
)
2421 static inline const char *rtn_scope(char *buf
, size_t len
, enum rt_scope_t s
)
2424 case RT_SCOPE_UNIVERSE
: return "universe";
2425 case RT_SCOPE_SITE
: return "site";
2426 case RT_SCOPE_LINK
: return "link";
2427 case RT_SCOPE_HOST
: return "host";
2428 case RT_SCOPE_NOWHERE
: return "nowhere";
2430 snprintf(buf
, len
, "scope=%d", s
);
2435 static const char *const rtn_type_names
[__RTN_MAX
] = {
2436 [RTN_UNSPEC
] = "UNSPEC",
2437 [RTN_UNICAST
] = "UNICAST",
2438 [RTN_LOCAL
] = "LOCAL",
2439 [RTN_BROADCAST
] = "BROADCAST",
2440 [RTN_ANYCAST
] = "ANYCAST",
2441 [RTN_MULTICAST
] = "MULTICAST",
2442 [RTN_BLACKHOLE
] = "BLACKHOLE",
2443 [RTN_UNREACHABLE
] = "UNREACHABLE",
2444 [RTN_PROHIBIT
] = "PROHIBIT",
2445 [RTN_THROW
] = "THROW",
2447 [RTN_XRESOLVE
] = "XRESOLVE",
2450 static inline const char *rtn_type(char *buf
, size_t len
, unsigned int t
)
2452 if (t
< __RTN_MAX
&& rtn_type_names
[t
])
2453 return rtn_type_names
[t
];
2454 snprintf(buf
, len
, "type %u", t
);
2458 /* Pretty print the trie */
2459 static int fib_trie_seq_show(struct seq_file
*seq
, void *v
)
2461 const struct fib_trie_iter
*iter
= seq
->private;
2462 struct key_vector
*n
= v
;
2464 if (IS_TRIE(node_parent_rcu(n
)))
2465 fib_table_print(seq
, iter
->tb
);
2468 __be32 prf
= htonl(n
->key
);
2470 seq_indent(seq
, iter
->depth
-1);
2471 seq_printf(seq
, " +-- %pI4/%zu %u %u %u\n",
2472 &prf
, KEYLENGTH
- n
->pos
- n
->bits
, n
->bits
,
2473 tn_info(n
)->full_children
,
2474 tn_info(n
)->empty_children
);
2476 __be32 val
= htonl(n
->key
);
2477 struct fib_alias
*fa
;
2479 seq_indent(seq
, iter
->depth
);
2480 seq_printf(seq
, " |-- %pI4\n", &val
);
2482 hlist_for_each_entry_rcu(fa
, &n
->leaf
, fa_list
) {
2483 char buf1
[32], buf2
[32];
2485 seq_indent(seq
, iter
->depth
+ 1);
2486 seq_printf(seq
, " /%zu %s %s",
2487 KEYLENGTH
- fa
->fa_slen
,
2488 rtn_scope(buf1
, sizeof(buf1
),
2489 fa
->fa_info
->fib_scope
),
2490 rtn_type(buf2
, sizeof(buf2
),
2493 seq_printf(seq
, " tos=%d", fa
->fa_tos
);
2494 seq_putc(seq
, '\n');
2501 static const struct seq_operations fib_trie_seq_ops
= {
2502 .start
= fib_trie_seq_start
,
2503 .next
= fib_trie_seq_next
,
2504 .stop
= fib_trie_seq_stop
,
2505 .show
= fib_trie_seq_show
,
2508 static int fib_trie_seq_open(struct inode
*inode
, struct file
*file
)
2510 return seq_open_net(inode
, file
, &fib_trie_seq_ops
,
2511 sizeof(struct fib_trie_iter
));
2514 static const struct file_operations fib_trie_fops
= {
2515 .owner
= THIS_MODULE
,
2516 .open
= fib_trie_seq_open
,
2518 .llseek
= seq_lseek
,
2519 .release
= seq_release_net
,
2522 struct fib_route_iter
{
2523 struct seq_net_private p
;
2524 struct fib_table
*main_tb
;
2525 struct key_vector
*tnode
;
2530 static struct key_vector
*fib_route_get_idx(struct fib_route_iter
*iter
,
2533 struct key_vector
*l
, **tp
= &iter
->tnode
;
2536 /* use cached location of previously found key */
2537 if (iter
->pos
> 0 && pos
>= iter
->pos
) {
2546 while ((l
= leaf_walk_rcu(tp
, key
)) && (pos
-- > 0)) {
2551 /* handle unlikely case of a key wrap */
2557 iter
->key
= l
->key
; /* remember it */
2559 iter
->pos
= 0; /* forget it */
2564 static void *fib_route_seq_start(struct seq_file
*seq
, loff_t
*pos
)
2567 struct fib_route_iter
*iter
= seq
->private;
2568 struct fib_table
*tb
;
2573 tb
= fib_get_table(seq_file_net(seq
), RT_TABLE_MAIN
);
2578 t
= (struct trie
*)tb
->tb_data
;
2579 iter
->tnode
= t
->kv
;
2582 return fib_route_get_idx(iter
, *pos
);
2585 iter
->key
= KEY_MAX
;
2587 return SEQ_START_TOKEN
;
2590 static void *fib_route_seq_next(struct seq_file
*seq
, void *v
, loff_t
*pos
)
2592 struct fib_route_iter
*iter
= seq
->private;
2593 struct key_vector
*l
= NULL
;
2594 t_key key
= iter
->key
+ 1;
2598 /* only allow key of 0 for start of sequence */
2599 if ((v
== SEQ_START_TOKEN
) || key
)
2600 l
= leaf_walk_rcu(&iter
->tnode
, key
);
2612 static void fib_route_seq_stop(struct seq_file
*seq
, void *v
)
2618 static unsigned int fib_flag_trans(int type
, __be32 mask
, const struct fib_info
*fi
)
2620 unsigned int flags
= 0;
2622 if (type
== RTN_UNREACHABLE
|| type
== RTN_PROHIBIT
)
2624 if (fi
&& fi
->fib_nh
->nh_gw
)
2625 flags
|= RTF_GATEWAY
;
2626 if (mask
== htonl(0xFFFFFFFF))
2633 * This outputs /proc/net/route.
2634 * The format of the file is not supposed to be changed
2635 * and needs to be same as fib_hash output to avoid breaking
2638 static int fib_route_seq_show(struct seq_file
*seq
, void *v
)
2640 struct fib_route_iter
*iter
= seq
->private;
2641 struct fib_table
*tb
= iter
->main_tb
;
2642 struct fib_alias
*fa
;
2643 struct key_vector
*l
= v
;
2646 if (v
== SEQ_START_TOKEN
) {
2647 seq_printf(seq
, "%-127s\n", "Iface\tDestination\tGateway "
2648 "\tFlags\tRefCnt\tUse\tMetric\tMask\t\tMTU"
2653 prefix
= htonl(l
->key
);
2655 hlist_for_each_entry_rcu(fa
, &l
->leaf
, fa_list
) {
2656 const struct fib_info
*fi
= fa
->fa_info
;
2657 __be32 mask
= inet_make_mask(KEYLENGTH
- fa
->fa_slen
);
2658 unsigned int flags
= fib_flag_trans(fa
->fa_type
, mask
, fi
);
2660 if ((fa
->fa_type
== RTN_BROADCAST
) ||
2661 (fa
->fa_type
== RTN_MULTICAST
))
2664 if (fa
->tb_id
!= tb
->tb_id
)
2667 seq_setwidth(seq
, 127);
2671 "%s\t%08X\t%08X\t%04X\t%d\t%u\t"
2672 "%d\t%08X\t%d\t%u\t%u",
2673 fi
->fib_dev
? fi
->fib_dev
->name
: "*",
2675 fi
->fib_nh
->nh_gw
, flags
, 0, 0,
2679 fi
->fib_advmss
+ 40 : 0),
2684 "*\t%08X\t%08X\t%04X\t%d\t%u\t"
2685 "%d\t%08X\t%d\t%u\t%u",
2686 prefix
, 0, flags
, 0, 0, 0,
2695 static const struct seq_operations fib_route_seq_ops
= {
2696 .start
= fib_route_seq_start
,
2697 .next
= fib_route_seq_next
,
2698 .stop
= fib_route_seq_stop
,
2699 .show
= fib_route_seq_show
,
2702 static int fib_route_seq_open(struct inode
*inode
, struct file
*file
)
2704 return seq_open_net(inode
, file
, &fib_route_seq_ops
,
2705 sizeof(struct fib_route_iter
));
2708 static const struct file_operations fib_route_fops
= {
2709 .owner
= THIS_MODULE
,
2710 .open
= fib_route_seq_open
,
2712 .llseek
= seq_lseek
,
2713 .release
= seq_release_net
,
2716 int __net_init
fib_proc_init(struct net
*net
)
2718 if (!proc_create("fib_trie", S_IRUGO
, net
->proc_net
, &fib_trie_fops
))
2721 if (!proc_create("fib_triestat", S_IRUGO
, net
->proc_net
,
2722 &fib_triestat_fops
))
2725 if (!proc_create("route", S_IRUGO
, net
->proc_net
, &fib_route_fops
))
2731 remove_proc_entry("fib_triestat", net
->proc_net
);
2733 remove_proc_entry("fib_trie", net
->proc_net
);
2738 void __net_exit
fib_proc_exit(struct net
*net
)
2740 remove_proc_entry("fib_trie", net
->proc_net
);
2741 remove_proc_entry("fib_triestat", net
->proc_net
);
2742 remove_proc_entry("route", net
->proc_net
);
2745 #endif /* CONFIG_PROC_FS */