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/cache.h>
54 #include <linux/uaccess.h>
55 #include <linux/bitops.h>
56 #include <linux/types.h>
57 #include <linux/kernel.h>
59 #include <linux/string.h>
60 #include <linux/socket.h>
61 #include <linux/sockios.h>
62 #include <linux/errno.h>
64 #include <linux/inet.h>
65 #include <linux/inetdevice.h>
66 #include <linux/netdevice.h>
67 #include <linux/if_arp.h>
68 #include <linux/proc_fs.h>
69 #include <linux/rcupdate.h>
70 #include <linux/skbuff.h>
71 #include <linux/netlink.h>
72 #include <linux/init.h>
73 #include <linux/list.h>
74 #include <linux/slab.h>
75 #include <linux/export.h>
76 #include <linux/vmalloc.h>
77 #include <linux/notifier.h>
78 #include <net/net_namespace.h>
80 #include <net/protocol.h>
81 #include <net/route.h>
84 #include <net/ip_fib.h>
85 #include <net/fib_notifier.h>
86 #include <trace/events/fib.h>
87 #include "fib_lookup.h"
89 static int call_fib_entry_notifier(struct notifier_block
*nb
, struct net
*net
,
90 enum fib_event_type event_type
, u32 dst
,
91 int dst_len
, struct fib_alias
*fa
)
93 struct fib_entry_notifier_info info
= {
101 return call_fib4_notifier(nb
, net
, event_type
, &info
.info
);
104 static int call_fib_entry_notifiers(struct net
*net
,
105 enum fib_event_type event_type
, u32 dst
,
106 int dst_len
, struct fib_alias
*fa
,
107 struct netlink_ext_ack
*extack
)
109 struct fib_entry_notifier_info info
= {
110 .info
.extack
= extack
,
118 return call_fib4_notifiers(net
, event_type
, &info
.info
);
121 #define MAX_STAT_DEPTH 32
123 #define KEYLENGTH (8*sizeof(t_key))
124 #define KEY_MAX ((t_key)~0)
126 typedef unsigned int t_key
;
128 #define IS_TRIE(n) ((n)->pos >= KEYLENGTH)
129 #define IS_TNODE(n) ((n)->bits)
130 #define IS_LEAF(n) (!(n)->bits)
134 unsigned char pos
; /* 2log(KEYLENGTH) bits needed */
135 unsigned char bits
; /* 2log(KEYLENGTH) bits needed */
138 /* This list pointer if valid if (pos | bits) == 0 (LEAF) */
139 struct hlist_head leaf
;
140 /* This array is valid if (pos | bits) > 0 (TNODE) */
141 struct key_vector __rcu
*tnode
[0];
147 t_key empty_children
; /* KEYLENGTH bits needed */
148 t_key full_children
; /* KEYLENGTH bits needed */
149 struct key_vector __rcu
*parent
;
150 struct key_vector kv
[1];
151 #define tn_bits kv[0].bits
154 #define TNODE_SIZE(n) offsetof(struct tnode, kv[0].tnode[n])
155 #define LEAF_SIZE TNODE_SIZE(1)
157 #ifdef CONFIG_IP_FIB_TRIE_STATS
158 struct trie_use_stats
{
160 unsigned int backtrack
;
161 unsigned int semantic_match_passed
;
162 unsigned int semantic_match_miss
;
163 unsigned int null_node_hit
;
164 unsigned int resize_node_skipped
;
169 unsigned int totdepth
;
170 unsigned int maxdepth
;
173 unsigned int nullpointers
;
174 unsigned int prefixes
;
175 unsigned int nodesizes
[MAX_STAT_DEPTH
];
179 struct key_vector kv
[1];
180 #ifdef CONFIG_IP_FIB_TRIE_STATS
181 struct trie_use_stats __percpu
*stats
;
185 static struct key_vector
*resize(struct trie
*t
, struct key_vector
*tn
);
186 static unsigned int tnode_free_size
;
189 * synchronize_rcu after call_rcu for outstanding dirty memory; it should be
190 * especially useful before resizing the root node with PREEMPT_NONE configs;
191 * the value was obtained experimentally, aiming to avoid visible slowdown.
193 unsigned int sysctl_fib_sync_mem
= 512 * 1024;
194 unsigned int sysctl_fib_sync_mem_min
= 64 * 1024;
195 unsigned int sysctl_fib_sync_mem_max
= 64 * 1024 * 1024;
197 static struct kmem_cache
*fn_alias_kmem __ro_after_init
;
198 static struct kmem_cache
*trie_leaf_kmem __ro_after_init
;
200 static inline struct tnode
*tn_info(struct key_vector
*kv
)
202 return container_of(kv
, struct tnode
, kv
[0]);
205 /* caller must hold RTNL */
206 #define node_parent(tn) rtnl_dereference(tn_info(tn)->parent)
207 #define get_child(tn, i) rtnl_dereference((tn)->tnode[i])
209 /* caller must hold RCU read lock or RTNL */
210 #define node_parent_rcu(tn) rcu_dereference_rtnl(tn_info(tn)->parent)
211 #define get_child_rcu(tn, i) rcu_dereference_rtnl((tn)->tnode[i])
213 /* wrapper for rcu_assign_pointer */
214 static inline void node_set_parent(struct key_vector
*n
, struct key_vector
*tp
)
217 rcu_assign_pointer(tn_info(n
)->parent
, tp
);
220 #define NODE_INIT_PARENT(n, p) RCU_INIT_POINTER(tn_info(n)->parent, p)
222 /* This provides us with the number of children in this node, in the case of a
223 * leaf this will return 0 meaning none of the children are accessible.
225 static inline unsigned long child_length(const struct key_vector
*tn
)
227 return (1ul << tn
->bits
) & ~(1ul);
230 #define get_cindex(key, kv) (((key) ^ (kv)->key) >> (kv)->pos)
232 static inline unsigned long get_index(t_key key
, struct key_vector
*kv
)
234 unsigned long index
= key
^ kv
->key
;
236 if ((BITS_PER_LONG
<= KEYLENGTH
) && (KEYLENGTH
== kv
->pos
))
239 return index
>> kv
->pos
;
242 /* To understand this stuff, an understanding of keys and all their bits is
243 * necessary. Every node in the trie has a key associated with it, but not
244 * all of the bits in that key are significant.
246 * Consider a node 'n' and its parent 'tp'.
248 * If n is a leaf, every bit in its key is significant. Its presence is
249 * necessitated by path compression, since during a tree traversal (when
250 * searching for a leaf - unless we are doing an insertion) we will completely
251 * ignore all skipped bits we encounter. Thus we need to verify, at the end of
252 * a potentially successful search, that we have indeed been walking the
255 * Note that we can never "miss" the correct key in the tree if present by
256 * following the wrong path. Path compression ensures that segments of the key
257 * that are the same for all keys with a given prefix are skipped, but the
258 * skipped part *is* identical for each node in the subtrie below the skipped
259 * bit! trie_insert() in this implementation takes care of that.
261 * if n is an internal node - a 'tnode' here, the various parts of its key
262 * have many different meanings.
265 * _________________________________________________________________
266 * | i | i | i | i | i | i | i | N | N | N | S | S | S | S | S | C |
267 * -----------------------------------------------------------------
268 * 31 30 29 28 27 26 25 24 23 22 21 20 19 18 17 16
270 * _________________________________________________________________
271 * | C | C | C | u | u | u | u | u | u | u | u | u | u | u | u | u |
272 * -----------------------------------------------------------------
273 * 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0
280 * First, let's just ignore the bits that come before the parent tp, that is
281 * the bits from (tp->pos + tp->bits) to 31. They are *known* but at this
282 * point we do not use them for anything.
284 * The bits from (tp->pos) to (tp->pos + tp->bits - 1) - "N", above - are the
285 * index into the parent's child array. That is, they will be used to find
286 * 'n' among tp's children.
288 * The bits from (n->pos + n->bits) to (tp->pos - 1) - "S" - are skipped bits
291 * All the bits we have seen so far are significant to the node n. The rest
292 * of the bits are really not needed or indeed known in n->key.
294 * The bits from (n->pos) to (n->pos + n->bits - 1) - "C" - are the index into
295 * n's child array, and will of course be different for each child.
297 * The rest of the bits, from 0 to (n->pos -1) - "u" - are completely unknown
301 static const int halve_threshold
= 25;
302 static const int inflate_threshold
= 50;
303 static const int halve_threshold_root
= 15;
304 static const int inflate_threshold_root
= 30;
306 static void __alias_free_mem(struct rcu_head
*head
)
308 struct fib_alias
*fa
= container_of(head
, struct fib_alias
, rcu
);
309 kmem_cache_free(fn_alias_kmem
, fa
);
312 static inline void alias_free_mem_rcu(struct fib_alias
*fa
)
314 call_rcu(&fa
->rcu
, __alias_free_mem
);
317 #define TNODE_KMALLOC_MAX \
318 ilog2((PAGE_SIZE - TNODE_SIZE(0)) / sizeof(struct key_vector *))
319 #define TNODE_VMALLOC_MAX \
320 ilog2((SIZE_MAX - TNODE_SIZE(0)) / sizeof(struct key_vector *))
322 static void __node_free_rcu(struct rcu_head
*head
)
324 struct tnode
*n
= container_of(head
, struct tnode
, rcu
);
327 kmem_cache_free(trie_leaf_kmem
, n
);
332 #define node_free(n) call_rcu(&tn_info(n)->rcu, __node_free_rcu)
334 static struct tnode
*tnode_alloc(int bits
)
338 /* verify bits is within bounds */
339 if (bits
> TNODE_VMALLOC_MAX
)
342 /* determine size and verify it is non-zero and didn't overflow */
343 size
= TNODE_SIZE(1ul << bits
);
345 if (size
<= PAGE_SIZE
)
346 return kzalloc(size
, GFP_KERNEL
);
348 return vzalloc(size
);
351 static inline void empty_child_inc(struct key_vector
*n
)
353 ++tn_info(n
)->empty_children
? : ++tn_info(n
)->full_children
;
356 static inline void empty_child_dec(struct key_vector
*n
)
358 tn_info(n
)->empty_children
-- ? : tn_info(n
)->full_children
--;
361 static struct key_vector
*leaf_new(t_key key
, struct fib_alias
*fa
)
363 struct key_vector
*l
;
366 kv
= kmem_cache_alloc(trie_leaf_kmem
, GFP_KERNEL
);
370 /* initialize key vector */
375 l
->slen
= fa
->fa_slen
;
377 /* link leaf to fib alias */
378 INIT_HLIST_HEAD(&l
->leaf
);
379 hlist_add_head(&fa
->fa_list
, &l
->leaf
);
384 static struct key_vector
*tnode_new(t_key key
, int pos
, int bits
)
386 unsigned int shift
= pos
+ bits
;
387 struct key_vector
*tn
;
390 /* verify bits and pos their msb bits clear and values are valid */
391 BUG_ON(!bits
|| (shift
> KEYLENGTH
));
393 tnode
= tnode_alloc(bits
);
397 pr_debug("AT %p s=%zu %zu\n", tnode
, TNODE_SIZE(0),
398 sizeof(struct key_vector
*) << bits
);
400 if (bits
== KEYLENGTH
)
401 tnode
->full_children
= 1;
403 tnode
->empty_children
= 1ul << bits
;
406 tn
->key
= (shift
< KEYLENGTH
) ? (key
>> shift
) << shift
: 0;
414 /* Check whether a tnode 'n' is "full", i.e. it is an internal node
415 * and no bits are skipped. See discussion in dyntree paper p. 6
417 static inline int tnode_full(struct key_vector
*tn
, struct key_vector
*n
)
419 return n
&& ((n
->pos
+ n
->bits
) == tn
->pos
) && IS_TNODE(n
);
422 /* Add a child at position i overwriting the old value.
423 * Update the value of full_children and empty_children.
425 static void put_child(struct key_vector
*tn
, unsigned long i
,
426 struct key_vector
*n
)
428 struct key_vector
*chi
= get_child(tn
, i
);
431 BUG_ON(i
>= child_length(tn
));
433 /* update emptyChildren, overflow into fullChildren */
439 /* update fullChildren */
440 wasfull
= tnode_full(tn
, chi
);
441 isfull
= tnode_full(tn
, n
);
443 if (wasfull
&& !isfull
)
444 tn_info(tn
)->full_children
--;
445 else if (!wasfull
&& isfull
)
446 tn_info(tn
)->full_children
++;
448 if (n
&& (tn
->slen
< n
->slen
))
451 rcu_assign_pointer(tn
->tnode
[i
], n
);
454 static void update_children(struct key_vector
*tn
)
458 /* update all of the child parent pointers */
459 for (i
= child_length(tn
); i
;) {
460 struct key_vector
*inode
= get_child(tn
, --i
);
465 /* Either update the children of a tnode that
466 * already belongs to us or update the child
467 * to point to ourselves.
469 if (node_parent(inode
) == tn
)
470 update_children(inode
);
472 node_set_parent(inode
, tn
);
476 static inline void put_child_root(struct key_vector
*tp
, t_key key
,
477 struct key_vector
*n
)
480 rcu_assign_pointer(tp
->tnode
[0], n
);
482 put_child(tp
, get_index(key
, tp
), n
);
485 static inline void tnode_free_init(struct key_vector
*tn
)
487 tn_info(tn
)->rcu
.next
= NULL
;
490 static inline void tnode_free_append(struct key_vector
*tn
,
491 struct key_vector
*n
)
493 tn_info(n
)->rcu
.next
= tn_info(tn
)->rcu
.next
;
494 tn_info(tn
)->rcu
.next
= &tn_info(n
)->rcu
;
497 static void tnode_free(struct key_vector
*tn
)
499 struct callback_head
*head
= &tn_info(tn
)->rcu
;
503 tnode_free_size
+= TNODE_SIZE(1ul << tn
->bits
);
506 tn
= container_of(head
, struct tnode
, rcu
)->kv
;
509 if (tnode_free_size
>= sysctl_fib_sync_mem
) {
515 static struct key_vector
*replace(struct trie
*t
,
516 struct key_vector
*oldtnode
,
517 struct key_vector
*tn
)
519 struct key_vector
*tp
= node_parent(oldtnode
);
522 /* setup the parent pointer out of and back into this node */
523 NODE_INIT_PARENT(tn
, tp
);
524 put_child_root(tp
, tn
->key
, tn
);
526 /* update all of the child parent pointers */
529 /* all pointers should be clean so we are done */
530 tnode_free(oldtnode
);
532 /* resize children now that oldtnode is freed */
533 for (i
= child_length(tn
); i
;) {
534 struct key_vector
*inode
= get_child(tn
, --i
);
536 /* resize child node */
537 if (tnode_full(tn
, inode
))
538 tn
= resize(t
, inode
);
544 static struct key_vector
*inflate(struct trie
*t
,
545 struct key_vector
*oldtnode
)
547 struct key_vector
*tn
;
551 pr_debug("In inflate\n");
553 tn
= tnode_new(oldtnode
->key
, oldtnode
->pos
- 1, oldtnode
->bits
+ 1);
557 /* prepare oldtnode to be freed */
558 tnode_free_init(oldtnode
);
560 /* Assemble all of the pointers in our cluster, in this case that
561 * represents all of the pointers out of our allocated nodes that
562 * point to existing tnodes and the links between our allocated
565 for (i
= child_length(oldtnode
), m
= 1u << tn
->pos
; i
;) {
566 struct key_vector
*inode
= get_child(oldtnode
, --i
);
567 struct key_vector
*node0
, *node1
;
574 /* A leaf or an internal node with skipped bits */
575 if (!tnode_full(oldtnode
, inode
)) {
576 put_child(tn
, get_index(inode
->key
, tn
), inode
);
580 /* drop the node in the old tnode free list */
581 tnode_free_append(oldtnode
, inode
);
583 /* An internal node with two children */
584 if (inode
->bits
== 1) {
585 put_child(tn
, 2 * i
+ 1, get_child(inode
, 1));
586 put_child(tn
, 2 * i
, get_child(inode
, 0));
590 /* We will replace this node 'inode' with two new
591 * ones, 'node0' and 'node1', each with half of the
592 * original children. The two new nodes will have
593 * a position one bit further down the key and this
594 * means that the "significant" part of their keys
595 * (see the discussion near the top of this file)
596 * will differ by one bit, which will be "0" in
597 * node0's key and "1" in node1's key. Since we are
598 * moving the key position by one step, the bit that
599 * we are moving away from - the bit at position
600 * (tn->pos) - is the one that will differ between
601 * node0 and node1. So... we synthesize that bit in the
604 node1
= tnode_new(inode
->key
| m
, inode
->pos
, inode
->bits
- 1);
607 node0
= tnode_new(inode
->key
, inode
->pos
, inode
->bits
- 1);
609 tnode_free_append(tn
, node1
);
612 tnode_free_append(tn
, node0
);
614 /* populate child pointers in new nodes */
615 for (k
= child_length(inode
), j
= k
/ 2; j
;) {
616 put_child(node1
, --j
, get_child(inode
, --k
));
617 put_child(node0
, j
, get_child(inode
, j
));
618 put_child(node1
, --j
, get_child(inode
, --k
));
619 put_child(node0
, j
, get_child(inode
, j
));
622 /* link new nodes to parent */
623 NODE_INIT_PARENT(node1
, tn
);
624 NODE_INIT_PARENT(node0
, tn
);
626 /* link parent to nodes */
627 put_child(tn
, 2 * i
+ 1, node1
);
628 put_child(tn
, 2 * i
, node0
);
631 /* setup the parent pointers into and out of this node */
632 return replace(t
, oldtnode
, tn
);
634 /* all pointers should be clean so we are done */
640 static struct key_vector
*halve(struct trie
*t
,
641 struct key_vector
*oldtnode
)
643 struct key_vector
*tn
;
646 pr_debug("In halve\n");
648 tn
= tnode_new(oldtnode
->key
, oldtnode
->pos
+ 1, oldtnode
->bits
- 1);
652 /* prepare oldtnode to be freed */
653 tnode_free_init(oldtnode
);
655 /* Assemble all of the pointers in our cluster, in this case that
656 * represents all of the pointers out of our allocated nodes that
657 * point to existing tnodes and the links between our allocated
660 for (i
= child_length(oldtnode
); i
;) {
661 struct key_vector
*node1
= get_child(oldtnode
, --i
);
662 struct key_vector
*node0
= get_child(oldtnode
, --i
);
663 struct key_vector
*inode
;
665 /* At least one of the children is empty */
666 if (!node1
|| !node0
) {
667 put_child(tn
, i
/ 2, node1
? : node0
);
671 /* Two nonempty children */
672 inode
= tnode_new(node0
->key
, oldtnode
->pos
, 1);
675 tnode_free_append(tn
, inode
);
677 /* initialize pointers out of node */
678 put_child(inode
, 1, node1
);
679 put_child(inode
, 0, node0
);
680 NODE_INIT_PARENT(inode
, tn
);
682 /* link parent to node */
683 put_child(tn
, i
/ 2, inode
);
686 /* setup the parent pointers into and out of this node */
687 return replace(t
, oldtnode
, tn
);
689 /* all pointers should be clean so we are done */
695 static struct key_vector
*collapse(struct trie
*t
,
696 struct key_vector
*oldtnode
)
698 struct key_vector
*n
, *tp
;
701 /* scan the tnode looking for that one child that might still exist */
702 for (n
= NULL
, i
= child_length(oldtnode
); !n
&& i
;)
703 n
= get_child(oldtnode
, --i
);
705 /* compress one level */
706 tp
= node_parent(oldtnode
);
707 put_child_root(tp
, oldtnode
->key
, n
);
708 node_set_parent(n
, tp
);
716 static unsigned char update_suffix(struct key_vector
*tn
)
718 unsigned char slen
= tn
->pos
;
719 unsigned long stride
, i
;
720 unsigned char slen_max
;
722 /* only vector 0 can have a suffix length greater than or equal to
723 * tn->pos + tn->bits, the second highest node will have a suffix
724 * length at most of tn->pos + tn->bits - 1
726 slen_max
= min_t(unsigned char, tn
->pos
+ tn
->bits
- 1, tn
->slen
);
728 /* search though the list of children looking for nodes that might
729 * have a suffix greater than the one we currently have. This is
730 * why we start with a stride of 2 since a stride of 1 would
731 * represent the nodes with suffix length equal to tn->pos
733 for (i
= 0, stride
= 0x2ul
; i
< child_length(tn
); i
+= stride
) {
734 struct key_vector
*n
= get_child(tn
, i
);
736 if (!n
|| (n
->slen
<= slen
))
739 /* update stride and slen based on new value */
740 stride
<<= (n
->slen
- slen
);
744 /* stop searching if we have hit the maximum possible value */
745 if (slen
>= slen_max
)
754 /* From "Implementing a dynamic compressed trie" by Stefan Nilsson of
755 * the Helsinki University of Technology and Matti Tikkanen of Nokia
756 * Telecommunications, page 6:
757 * "A node is doubled if the ratio of non-empty children to all
758 * children in the *doubled* node is at least 'high'."
760 * 'high' in this instance is the variable 'inflate_threshold'. It
761 * is expressed as a percentage, so we multiply it with
762 * child_length() and instead of multiplying by 2 (since the
763 * child array will be doubled by inflate()) and multiplying
764 * the left-hand side by 100 (to handle the percentage thing) we
765 * multiply the left-hand side by 50.
767 * The left-hand side may look a bit weird: child_length(tn)
768 * - tn->empty_children is of course the number of non-null children
769 * in the current node. tn->full_children is the number of "full"
770 * children, that is non-null tnodes with a skip value of 0.
771 * All of those will be doubled in the resulting inflated tnode, so
772 * we just count them one extra time here.
774 * A clearer way to write this would be:
776 * to_be_doubled = tn->full_children;
777 * not_to_be_doubled = child_length(tn) - tn->empty_children -
780 * new_child_length = child_length(tn) * 2;
782 * new_fill_factor = 100 * (not_to_be_doubled + 2*to_be_doubled) /
784 * if (new_fill_factor >= inflate_threshold)
786 * ...and so on, tho it would mess up the while () loop.
789 * 100 * (not_to_be_doubled + 2*to_be_doubled) / new_child_length >=
793 * 100 * (not_to_be_doubled + 2*to_be_doubled) >=
794 * inflate_threshold * new_child_length
796 * expand not_to_be_doubled and to_be_doubled, and shorten:
797 * 100 * (child_length(tn) - tn->empty_children +
798 * tn->full_children) >= inflate_threshold * new_child_length
800 * expand new_child_length:
801 * 100 * (child_length(tn) - tn->empty_children +
802 * tn->full_children) >=
803 * inflate_threshold * child_length(tn) * 2
806 * 50 * (tn->full_children + child_length(tn) -
807 * tn->empty_children) >= inflate_threshold *
811 static inline bool should_inflate(struct key_vector
*tp
, struct key_vector
*tn
)
813 unsigned long used
= child_length(tn
);
814 unsigned long threshold
= used
;
816 /* Keep root node larger */
817 threshold
*= IS_TRIE(tp
) ? inflate_threshold_root
: inflate_threshold
;
818 used
-= tn_info(tn
)->empty_children
;
819 used
+= tn_info(tn
)->full_children
;
821 /* if bits == KEYLENGTH then pos = 0, and will fail below */
823 return (used
> 1) && tn
->pos
&& ((50 * used
) >= threshold
);
826 static inline bool should_halve(struct key_vector
*tp
, struct key_vector
*tn
)
828 unsigned long used
= child_length(tn
);
829 unsigned long threshold
= used
;
831 /* Keep root node larger */
832 threshold
*= IS_TRIE(tp
) ? halve_threshold_root
: halve_threshold
;
833 used
-= tn_info(tn
)->empty_children
;
835 /* if bits == KEYLENGTH then used = 100% on wrap, and will fail below */
837 return (used
> 1) && (tn
->bits
> 1) && ((100 * used
) < threshold
);
840 static inline bool should_collapse(struct key_vector
*tn
)
842 unsigned long used
= child_length(tn
);
844 used
-= tn_info(tn
)->empty_children
;
846 /* account for bits == KEYLENGTH case */
847 if ((tn
->bits
== KEYLENGTH
) && tn_info(tn
)->full_children
)
850 /* One child or none, time to drop us from the trie */
855 static struct key_vector
*resize(struct trie
*t
, struct key_vector
*tn
)
857 #ifdef CONFIG_IP_FIB_TRIE_STATS
858 struct trie_use_stats __percpu
*stats
= t
->stats
;
860 struct key_vector
*tp
= node_parent(tn
);
861 unsigned long cindex
= get_index(tn
->key
, tp
);
862 int max_work
= MAX_WORK
;
864 pr_debug("In tnode_resize %p inflate_threshold=%d threshold=%d\n",
865 tn
, inflate_threshold
, halve_threshold
);
867 /* track the tnode via the pointer from the parent instead of
868 * doing it ourselves. This way we can let RCU fully do its
869 * thing without us interfering
871 BUG_ON(tn
!= get_child(tp
, cindex
));
873 /* Double as long as the resulting node has a number of
874 * nonempty nodes that are above the threshold.
876 while (should_inflate(tp
, tn
) && max_work
) {
879 #ifdef CONFIG_IP_FIB_TRIE_STATS
880 this_cpu_inc(stats
->resize_node_skipped
);
886 tn
= get_child(tp
, cindex
);
889 /* update parent in case inflate failed */
890 tp
= node_parent(tn
);
892 /* Return if at least one inflate is run */
893 if (max_work
!= MAX_WORK
)
896 /* Halve as long as the number of empty children in this
897 * node is above threshold.
899 while (should_halve(tp
, tn
) && max_work
) {
902 #ifdef CONFIG_IP_FIB_TRIE_STATS
903 this_cpu_inc(stats
->resize_node_skipped
);
909 tn
= get_child(tp
, cindex
);
912 /* Only one child remains */
913 if (should_collapse(tn
))
914 return collapse(t
, tn
);
916 /* update parent in case halve failed */
917 return node_parent(tn
);
920 static void node_pull_suffix(struct key_vector
*tn
, unsigned char slen
)
922 unsigned char node_slen
= tn
->slen
;
924 while ((node_slen
> tn
->pos
) && (node_slen
> slen
)) {
925 slen
= update_suffix(tn
);
926 if (node_slen
== slen
)
929 tn
= node_parent(tn
);
930 node_slen
= tn
->slen
;
934 static void node_push_suffix(struct key_vector
*tn
, unsigned char slen
)
936 while (tn
->slen
< slen
) {
938 tn
= node_parent(tn
);
942 /* rcu_read_lock needs to be hold by caller from readside */
943 static struct key_vector
*fib_find_node(struct trie
*t
,
944 struct key_vector
**tp
, u32 key
)
946 struct key_vector
*pn
, *n
= t
->kv
;
947 unsigned long index
= 0;
951 n
= get_child_rcu(n
, index
);
956 index
= get_cindex(key
, n
);
958 /* This bit of code is a bit tricky but it combines multiple
959 * checks into a single check. The prefix consists of the
960 * prefix plus zeros for the bits in the cindex. The index
961 * is the difference between the key and this value. From
962 * this we can actually derive several pieces of data.
963 * if (index >= (1ul << bits))
964 * we have a mismatch in skip bits and failed
966 * we know the value is cindex
968 * This check is safe even if bits == KEYLENGTH due to the
969 * fact that we can only allocate a node with 32 bits if a
970 * long is greater than 32 bits.
972 if (index
>= (1ul << n
->bits
)) {
977 /* keep searching until we find a perfect match leaf or NULL */
978 } while (IS_TNODE(n
));
985 /* Return the first fib alias matching TOS with
986 * priority less than or equal to PRIO.
988 static struct fib_alias
*fib_find_alias(struct hlist_head
*fah
, u8 slen
,
989 u8 tos
, u32 prio
, u32 tb_id
)
991 struct fib_alias
*fa
;
996 hlist_for_each_entry(fa
, fah
, fa_list
) {
997 if (fa
->fa_slen
< slen
)
999 if (fa
->fa_slen
!= slen
)
1001 if (fa
->tb_id
> tb_id
)
1003 if (fa
->tb_id
!= tb_id
)
1005 if (fa
->fa_tos
> tos
)
1007 if (fa
->fa_info
->fib_priority
>= prio
|| fa
->fa_tos
< tos
)
1014 static void trie_rebalance(struct trie
*t
, struct key_vector
*tn
)
1016 while (!IS_TRIE(tn
))
1020 static int fib_insert_node(struct trie
*t
, struct key_vector
*tp
,
1021 struct fib_alias
*new, t_key key
)
1023 struct key_vector
*n
, *l
;
1025 l
= leaf_new(key
, new);
1029 /* retrieve child from parent node */
1030 n
= get_child(tp
, get_index(key
, tp
));
1032 /* Case 2: n is a LEAF or a TNODE and the key doesn't match.
1034 * Add a new tnode here
1035 * first tnode need some special handling
1036 * leaves us in position for handling as case 3
1039 struct key_vector
*tn
;
1041 tn
= tnode_new(key
, __fls(key
^ n
->key
), 1);
1045 /* initialize routes out of node */
1046 NODE_INIT_PARENT(tn
, tp
);
1047 put_child(tn
, get_index(key
, tn
) ^ 1, n
);
1049 /* start adding routes into the node */
1050 put_child_root(tp
, key
, tn
);
1051 node_set_parent(n
, tn
);
1053 /* parent now has a NULL spot where the leaf can go */
1057 /* Case 3: n is NULL, and will just insert a new leaf */
1058 node_push_suffix(tp
, new->fa_slen
);
1059 NODE_INIT_PARENT(l
, tp
);
1060 put_child_root(tp
, key
, l
);
1061 trie_rebalance(t
, tp
);
1070 /* fib notifier for ADD is sent before calling fib_insert_alias with
1071 * the expectation that the only possible failure ENOMEM
1073 static int fib_insert_alias(struct trie
*t
, struct key_vector
*tp
,
1074 struct key_vector
*l
, struct fib_alias
*new,
1075 struct fib_alias
*fa
, t_key key
)
1078 return fib_insert_node(t
, tp
, new, key
);
1081 hlist_add_before_rcu(&new->fa_list
, &fa
->fa_list
);
1083 struct fib_alias
*last
;
1085 hlist_for_each_entry(last
, &l
->leaf
, fa_list
) {
1086 if (new->fa_slen
< last
->fa_slen
)
1088 if ((new->fa_slen
== last
->fa_slen
) &&
1089 (new->tb_id
> last
->tb_id
))
1095 hlist_add_behind_rcu(&new->fa_list
, &fa
->fa_list
);
1097 hlist_add_head_rcu(&new->fa_list
, &l
->leaf
);
1100 /* if we added to the tail node then we need to update slen */
1101 if (l
->slen
< new->fa_slen
) {
1102 l
->slen
= new->fa_slen
;
1103 node_push_suffix(tp
, new->fa_slen
);
1109 static bool fib_valid_key_len(u32 key
, u8 plen
, struct netlink_ext_ack
*extack
)
1111 if (plen
> KEYLENGTH
) {
1112 NL_SET_ERR_MSG(extack
, "Invalid prefix length");
1116 if ((plen
< KEYLENGTH
) && (key
<< plen
)) {
1117 NL_SET_ERR_MSG(extack
,
1118 "Invalid prefix for given prefix length");
1125 /* Caller must hold RTNL. */
1126 int fib_table_insert(struct net
*net
, struct fib_table
*tb
,
1127 struct fib_config
*cfg
, struct netlink_ext_ack
*extack
)
1129 enum fib_event_type event
= FIB_EVENT_ENTRY_ADD
;
1130 struct trie
*t
= (struct trie
*)tb
->tb_data
;
1131 struct fib_alias
*fa
, *new_fa
;
1132 struct key_vector
*l
, *tp
;
1133 u16 nlflags
= NLM_F_EXCL
;
1134 struct fib_info
*fi
;
1135 u8 plen
= cfg
->fc_dst_len
;
1136 u8 slen
= KEYLENGTH
- plen
;
1137 u8 tos
= cfg
->fc_tos
;
1141 key
= ntohl(cfg
->fc_dst
);
1143 if (!fib_valid_key_len(key
, plen
, extack
))
1146 pr_debug("Insert table=%u %08x/%d\n", tb
->tb_id
, key
, plen
);
1148 fi
= fib_create_info(cfg
, extack
);
1154 l
= fib_find_node(t
, &tp
, key
);
1155 fa
= l
? fib_find_alias(&l
->leaf
, slen
, tos
, fi
->fib_priority
,
1158 /* Now fa, if non-NULL, points to the first fib alias
1159 * with the same keys [prefix,tos,priority], if such key already
1160 * exists or to the node before which we will insert new one.
1162 * If fa is NULL, we will need to allocate a new one and
1163 * insert to the tail of the section matching the suffix length
1167 if (fa
&& fa
->fa_tos
== tos
&&
1168 fa
->fa_info
->fib_priority
== fi
->fib_priority
) {
1169 struct fib_alias
*fa_first
, *fa_match
;
1172 if (cfg
->fc_nlflags
& NLM_F_EXCL
)
1175 nlflags
&= ~NLM_F_EXCL
;
1178 * 1. Find exact match for type, scope, fib_info to avoid
1180 * 2. Find next 'fa' (or head), NLM_F_APPEND inserts before it
1184 hlist_for_each_entry_from(fa
, fa_list
) {
1185 if ((fa
->fa_slen
!= slen
) ||
1186 (fa
->tb_id
!= tb
->tb_id
) ||
1187 (fa
->fa_tos
!= tos
))
1189 if (fa
->fa_info
->fib_priority
!= fi
->fib_priority
)
1191 if (fa
->fa_type
== cfg
->fc_type
&&
1192 fa
->fa_info
== fi
) {
1198 if (cfg
->fc_nlflags
& NLM_F_REPLACE
) {
1199 struct fib_info
*fi_drop
;
1202 nlflags
|= NLM_F_REPLACE
;
1210 new_fa
= kmem_cache_alloc(fn_alias_kmem
, GFP_KERNEL
);
1214 fi_drop
= fa
->fa_info
;
1215 new_fa
->fa_tos
= fa
->fa_tos
;
1216 new_fa
->fa_info
= fi
;
1217 new_fa
->fa_type
= cfg
->fc_type
;
1218 state
= fa
->fa_state
;
1219 new_fa
->fa_state
= state
& ~FA_S_ACCESSED
;
1220 new_fa
->fa_slen
= fa
->fa_slen
;
1221 new_fa
->tb_id
= tb
->tb_id
;
1222 new_fa
->fa_default
= -1;
1224 err
= call_fib_entry_notifiers(net
,
1225 FIB_EVENT_ENTRY_REPLACE
,
1229 goto out_free_new_fa
;
1231 rtmsg_fib(RTM_NEWROUTE
, htonl(key
), new_fa
, plen
,
1232 tb
->tb_id
, &cfg
->fc_nlinfo
, nlflags
);
1234 hlist_replace_rcu(&fa
->fa_list
, &new_fa
->fa_list
);
1236 alias_free_mem_rcu(fa
);
1238 fib_release_info(fi_drop
);
1239 if (state
& FA_S_ACCESSED
)
1240 rt_cache_flush(cfg
->fc_nlinfo
.nl_net
);
1244 /* Error if we find a perfect match which
1245 * uses the same scope, type, and nexthop
1251 if (cfg
->fc_nlflags
& NLM_F_APPEND
) {
1252 event
= FIB_EVENT_ENTRY_APPEND
;
1253 nlflags
|= NLM_F_APPEND
;
1259 if (!(cfg
->fc_nlflags
& NLM_F_CREATE
))
1262 nlflags
|= NLM_F_CREATE
;
1264 new_fa
= kmem_cache_alloc(fn_alias_kmem
, GFP_KERNEL
);
1268 new_fa
->fa_info
= fi
;
1269 new_fa
->fa_tos
= tos
;
1270 new_fa
->fa_type
= cfg
->fc_type
;
1271 new_fa
->fa_state
= 0;
1272 new_fa
->fa_slen
= slen
;
1273 new_fa
->tb_id
= tb
->tb_id
;
1274 new_fa
->fa_default
= -1;
1276 err
= call_fib_entry_notifiers(net
, event
, key
, plen
, new_fa
, extack
);
1278 goto out_free_new_fa
;
1280 /* Insert new entry to the list. */
1281 err
= fib_insert_alias(t
, tp
, l
, new_fa
, fa
, key
);
1286 tb
->tb_num_default
++;
1288 rt_cache_flush(cfg
->fc_nlinfo
.nl_net
);
1289 rtmsg_fib(RTM_NEWROUTE
, htonl(key
), new_fa
, plen
, new_fa
->tb_id
,
1290 &cfg
->fc_nlinfo
, nlflags
);
1295 /* notifier was sent that entry would be added to trie, but
1296 * the add failed and need to recover. Only failure for
1297 * fib_insert_alias is ENOMEM.
1299 NL_SET_ERR_MSG(extack
, "Failed to insert route into trie");
1300 call_fib_entry_notifiers(net
, FIB_EVENT_ENTRY_DEL
, key
,
1301 plen
, new_fa
, NULL
);
1303 kmem_cache_free(fn_alias_kmem
, new_fa
);
1305 fib_release_info(fi
);
1310 static inline t_key
prefix_mismatch(t_key key
, struct key_vector
*n
)
1312 t_key prefix
= n
->key
;
1314 return (key
^ prefix
) & (prefix
| -prefix
);
1317 /* should be called with rcu_read_lock */
1318 int fib_table_lookup(struct fib_table
*tb
, const struct flowi4
*flp
,
1319 struct fib_result
*res
, int fib_flags
)
1321 struct trie
*t
= (struct trie
*) tb
->tb_data
;
1322 #ifdef CONFIG_IP_FIB_TRIE_STATS
1323 struct trie_use_stats __percpu
*stats
= t
->stats
;
1325 const t_key key
= ntohl(flp
->daddr
);
1326 struct key_vector
*n
, *pn
;
1327 struct fib_alias
*fa
;
1328 unsigned long index
;
1334 n
= get_child_rcu(pn
, cindex
);
1336 trace_fib_table_lookup(tb
->tb_id
, flp
, NULL
, -EAGAIN
);
1340 #ifdef CONFIG_IP_FIB_TRIE_STATS
1341 this_cpu_inc(stats
->gets
);
1344 /* Step 1: Travel to the longest prefix match in the trie */
1346 index
= get_cindex(key
, n
);
1348 /* This bit of code is a bit tricky but it combines multiple
1349 * checks into a single check. The prefix consists of the
1350 * prefix plus zeros for the "bits" in the prefix. The index
1351 * is the difference between the key and this value. From
1352 * this we can actually derive several pieces of data.
1353 * if (index >= (1ul << bits))
1354 * we have a mismatch in skip bits and failed
1356 * we know the value is cindex
1358 * This check is safe even if bits == KEYLENGTH due to the
1359 * fact that we can only allocate a node with 32 bits if a
1360 * long is greater than 32 bits.
1362 if (index
>= (1ul << n
->bits
))
1365 /* we have found a leaf. Prefixes have already been compared */
1369 /* only record pn and cindex if we are going to be chopping
1370 * bits later. Otherwise we are just wasting cycles.
1372 if (n
->slen
> n
->pos
) {
1377 n
= get_child_rcu(n
, index
);
1382 /* Step 2: Sort out leaves and begin backtracing for longest prefix */
1384 /* record the pointer where our next node pointer is stored */
1385 struct key_vector __rcu
**cptr
= n
->tnode
;
1387 /* This test verifies that none of the bits that differ
1388 * between the key and the prefix exist in the region of
1389 * the lsb and higher in the prefix.
1391 if (unlikely(prefix_mismatch(key
, n
)) || (n
->slen
== n
->pos
))
1394 /* exit out and process leaf */
1395 if (unlikely(IS_LEAF(n
)))
1398 /* Don't bother recording parent info. Since we are in
1399 * prefix match mode we will have to come back to wherever
1400 * we started this traversal anyway
1403 while ((n
= rcu_dereference(*cptr
)) == NULL
) {
1405 #ifdef CONFIG_IP_FIB_TRIE_STATS
1407 this_cpu_inc(stats
->null_node_hit
);
1409 /* If we are at cindex 0 there are no more bits for
1410 * us to strip at this level so we must ascend back
1411 * up one level to see if there are any more bits to
1412 * be stripped there.
1415 t_key pkey
= pn
->key
;
1417 /* If we don't have a parent then there is
1418 * nothing for us to do as we do not have any
1419 * further nodes to parse.
1422 trace_fib_table_lookup(tb
->tb_id
, flp
,
1426 #ifdef CONFIG_IP_FIB_TRIE_STATS
1427 this_cpu_inc(stats
->backtrack
);
1429 /* Get Child's index */
1430 pn
= node_parent_rcu(pn
);
1431 cindex
= get_index(pkey
, pn
);
1434 /* strip the least significant bit from the cindex */
1435 cindex
&= cindex
- 1;
1437 /* grab pointer for next child node */
1438 cptr
= &pn
->tnode
[cindex
];
1443 /* this line carries forward the xor from earlier in the function */
1444 index
= key
^ n
->key
;
1446 /* Step 3: Process the leaf, if that fails fall back to backtracing */
1447 hlist_for_each_entry_rcu(fa
, &n
->leaf
, fa_list
) {
1448 struct fib_info
*fi
= fa
->fa_info
;
1451 if ((BITS_PER_LONG
> KEYLENGTH
) || (fa
->fa_slen
< KEYLENGTH
)) {
1452 if (index
>= (1ul << fa
->fa_slen
))
1455 if (fa
->fa_tos
&& fa
->fa_tos
!= flp
->flowi4_tos
)
1459 if (fa
->fa_info
->fib_scope
< flp
->flowi4_scope
)
1461 fib_alias_accessed(fa
);
1462 err
= fib_props
[fa
->fa_type
].error
;
1463 if (unlikely(err
< 0)) {
1464 #ifdef CONFIG_IP_FIB_TRIE_STATS
1465 this_cpu_inc(stats
->semantic_match_passed
);
1467 trace_fib_table_lookup(tb
->tb_id
, flp
, NULL
, err
);
1470 if (fi
->fib_flags
& RTNH_F_DEAD
)
1472 for (nhsel
= 0; nhsel
< fi
->fib_nhs
; nhsel
++) {
1473 struct fib_nh_common
*nhc
= fib_info_nhc(fi
, nhsel
);
1475 if (nhc
->nhc_flags
& RTNH_F_DEAD
)
1477 if (ip_ignore_linkdown(nhc
->nhc_dev
) &&
1478 nhc
->nhc_flags
& RTNH_F_LINKDOWN
&&
1479 !(fib_flags
& FIB_LOOKUP_IGNORE_LINKSTATE
))
1481 if (!(flp
->flowi4_flags
& FLOWI_FLAG_SKIP_NH_OIF
)) {
1482 if (flp
->flowi4_oif
&&
1483 flp
->flowi4_oif
!= nhc
->nhc_oif
)
1487 if (!(fib_flags
& FIB_LOOKUP_NOREF
))
1488 refcount_inc(&fi
->fib_clntref
);
1490 res
->prefix
= htonl(n
->key
);
1491 res
->prefixlen
= KEYLENGTH
- fa
->fa_slen
;
1492 res
->nh_sel
= nhsel
;
1494 res
->type
= fa
->fa_type
;
1495 res
->scope
= fi
->fib_scope
;
1498 res
->fa_head
= &n
->leaf
;
1499 #ifdef CONFIG_IP_FIB_TRIE_STATS
1500 this_cpu_inc(stats
->semantic_match_passed
);
1502 trace_fib_table_lookup(tb
->tb_id
, flp
, nhc
, err
);
1507 #ifdef CONFIG_IP_FIB_TRIE_STATS
1508 this_cpu_inc(stats
->semantic_match_miss
);
1512 EXPORT_SYMBOL_GPL(fib_table_lookup
);
1514 static void fib_remove_alias(struct trie
*t
, struct key_vector
*tp
,
1515 struct key_vector
*l
, struct fib_alias
*old
)
1517 /* record the location of the previous list_info entry */
1518 struct hlist_node
**pprev
= old
->fa_list
.pprev
;
1519 struct fib_alias
*fa
= hlist_entry(pprev
, typeof(*fa
), fa_list
.next
);
1521 /* remove the fib_alias from the list */
1522 hlist_del_rcu(&old
->fa_list
);
1524 /* if we emptied the list this leaf will be freed and we can sort
1525 * out parent suffix lengths as a part of trie_rebalance
1527 if (hlist_empty(&l
->leaf
)) {
1528 if (tp
->slen
== l
->slen
)
1529 node_pull_suffix(tp
, tp
->pos
);
1530 put_child_root(tp
, l
->key
, NULL
);
1532 trie_rebalance(t
, tp
);
1536 /* only access fa if it is pointing at the last valid hlist_node */
1540 /* update the trie with the latest suffix length */
1541 l
->slen
= fa
->fa_slen
;
1542 node_pull_suffix(tp
, fa
->fa_slen
);
1545 /* Caller must hold RTNL. */
1546 int fib_table_delete(struct net
*net
, struct fib_table
*tb
,
1547 struct fib_config
*cfg
, struct netlink_ext_ack
*extack
)
1549 struct trie
*t
= (struct trie
*) tb
->tb_data
;
1550 struct fib_alias
*fa
, *fa_to_delete
;
1551 struct key_vector
*l
, *tp
;
1552 u8 plen
= cfg
->fc_dst_len
;
1553 u8 slen
= KEYLENGTH
- plen
;
1554 u8 tos
= cfg
->fc_tos
;
1557 key
= ntohl(cfg
->fc_dst
);
1559 if (!fib_valid_key_len(key
, plen
, extack
))
1562 l
= fib_find_node(t
, &tp
, key
);
1566 fa
= fib_find_alias(&l
->leaf
, slen
, tos
, 0, tb
->tb_id
);
1570 pr_debug("Deleting %08x/%d tos=%d t=%p\n", key
, plen
, tos
, t
);
1572 fa_to_delete
= NULL
;
1573 hlist_for_each_entry_from(fa
, fa_list
) {
1574 struct fib_info
*fi
= fa
->fa_info
;
1576 if ((fa
->fa_slen
!= slen
) ||
1577 (fa
->tb_id
!= tb
->tb_id
) ||
1578 (fa
->fa_tos
!= tos
))
1581 if ((!cfg
->fc_type
|| fa
->fa_type
== cfg
->fc_type
) &&
1582 (cfg
->fc_scope
== RT_SCOPE_NOWHERE
||
1583 fa
->fa_info
->fib_scope
== cfg
->fc_scope
) &&
1584 (!cfg
->fc_prefsrc
||
1585 fi
->fib_prefsrc
== cfg
->fc_prefsrc
) &&
1586 (!cfg
->fc_protocol
||
1587 fi
->fib_protocol
== cfg
->fc_protocol
) &&
1588 fib_nh_match(cfg
, fi
, extack
) == 0 &&
1589 fib_metrics_match(cfg
, fi
)) {
1598 call_fib_entry_notifiers(net
, FIB_EVENT_ENTRY_DEL
, key
, plen
,
1599 fa_to_delete
, extack
);
1600 rtmsg_fib(RTM_DELROUTE
, htonl(key
), fa_to_delete
, plen
, tb
->tb_id
,
1601 &cfg
->fc_nlinfo
, 0);
1604 tb
->tb_num_default
--;
1606 fib_remove_alias(t
, tp
, l
, fa_to_delete
);
1608 if (fa_to_delete
->fa_state
& FA_S_ACCESSED
)
1609 rt_cache_flush(cfg
->fc_nlinfo
.nl_net
);
1611 fib_release_info(fa_to_delete
->fa_info
);
1612 alias_free_mem_rcu(fa_to_delete
);
1616 /* Scan for the next leaf starting at the provided key value */
1617 static struct key_vector
*leaf_walk_rcu(struct key_vector
**tn
, t_key key
)
1619 struct key_vector
*pn
, *n
= *tn
;
1620 unsigned long cindex
;
1622 /* this loop is meant to try and find the key in the trie */
1624 /* record parent and next child index */
1626 cindex
= (key
> pn
->key
) ? get_index(key
, pn
) : 0;
1628 if (cindex
>> pn
->bits
)
1631 /* descend into the next child */
1632 n
= get_child_rcu(pn
, cindex
++);
1636 /* guarantee forward progress on the keys */
1637 if (IS_LEAF(n
) && (n
->key
>= key
))
1639 } while (IS_TNODE(n
));
1641 /* this loop will search for the next leaf with a greater key */
1642 while (!IS_TRIE(pn
)) {
1643 /* if we exhausted the parent node we will need to climb */
1644 if (cindex
>= (1ul << pn
->bits
)) {
1645 t_key pkey
= pn
->key
;
1647 pn
= node_parent_rcu(pn
);
1648 cindex
= get_index(pkey
, pn
) + 1;
1652 /* grab the next available node */
1653 n
= get_child_rcu(pn
, cindex
++);
1657 /* no need to compare keys since we bumped the index */
1661 /* Rescan start scanning in new node */
1667 return NULL
; /* Root of trie */
1669 /* if we are at the limit for keys just return NULL for the tnode */
1674 static void fib_trie_free(struct fib_table
*tb
)
1676 struct trie
*t
= (struct trie
*)tb
->tb_data
;
1677 struct key_vector
*pn
= t
->kv
;
1678 unsigned long cindex
= 1;
1679 struct hlist_node
*tmp
;
1680 struct fib_alias
*fa
;
1682 /* walk trie in reverse order and free everything */
1684 struct key_vector
*n
;
1687 t_key pkey
= pn
->key
;
1693 pn
= node_parent(pn
);
1695 /* drop emptied tnode */
1696 put_child_root(pn
, n
->key
, NULL
);
1699 cindex
= get_index(pkey
, pn
);
1704 /* grab the next available node */
1705 n
= get_child(pn
, cindex
);
1710 /* record pn and cindex for leaf walking */
1712 cindex
= 1ul << n
->bits
;
1717 hlist_for_each_entry_safe(fa
, tmp
, &n
->leaf
, fa_list
) {
1718 hlist_del_rcu(&fa
->fa_list
);
1719 alias_free_mem_rcu(fa
);
1722 put_child_root(pn
, n
->key
, NULL
);
1726 #ifdef CONFIG_IP_FIB_TRIE_STATS
1727 free_percpu(t
->stats
);
1732 struct fib_table
*fib_trie_unmerge(struct fib_table
*oldtb
)
1734 struct trie
*ot
= (struct trie
*)oldtb
->tb_data
;
1735 struct key_vector
*l
, *tp
= ot
->kv
;
1736 struct fib_table
*local_tb
;
1737 struct fib_alias
*fa
;
1741 if (oldtb
->tb_data
== oldtb
->__data
)
1744 local_tb
= fib_trie_table(RT_TABLE_LOCAL
, NULL
);
1748 lt
= (struct trie
*)local_tb
->tb_data
;
1750 while ((l
= leaf_walk_rcu(&tp
, key
)) != NULL
) {
1751 struct key_vector
*local_l
= NULL
, *local_tp
;
1753 hlist_for_each_entry_rcu(fa
, &l
->leaf
, fa_list
) {
1754 struct fib_alias
*new_fa
;
1756 if (local_tb
->tb_id
!= fa
->tb_id
)
1759 /* clone fa for new local table */
1760 new_fa
= kmem_cache_alloc(fn_alias_kmem
, GFP_KERNEL
);
1764 memcpy(new_fa
, fa
, sizeof(*fa
));
1766 /* insert clone into table */
1768 local_l
= fib_find_node(lt
, &local_tp
, l
->key
);
1770 if (fib_insert_alias(lt
, local_tp
, local_l
, new_fa
,
1772 kmem_cache_free(fn_alias_kmem
, new_fa
);
1777 /* stop loop if key wrapped back to 0 */
1785 fib_trie_free(local_tb
);
1790 /* Caller must hold RTNL */
1791 void fib_table_flush_external(struct fib_table
*tb
)
1793 struct trie
*t
= (struct trie
*)tb
->tb_data
;
1794 struct key_vector
*pn
= t
->kv
;
1795 unsigned long cindex
= 1;
1796 struct hlist_node
*tmp
;
1797 struct fib_alias
*fa
;
1799 /* walk trie in reverse order */
1801 unsigned char slen
= 0;
1802 struct key_vector
*n
;
1805 t_key pkey
= pn
->key
;
1807 /* cannot resize the trie vector */
1811 /* update the suffix to address pulled leaves */
1812 if (pn
->slen
> pn
->pos
)
1815 /* resize completed node */
1817 cindex
= get_index(pkey
, pn
);
1822 /* grab the next available node */
1823 n
= get_child(pn
, cindex
);
1828 /* record pn and cindex for leaf walking */
1830 cindex
= 1ul << n
->bits
;
1835 hlist_for_each_entry_safe(fa
, tmp
, &n
->leaf
, fa_list
) {
1836 /* if alias was cloned to local then we just
1837 * need to remove the local copy from main
1839 if (tb
->tb_id
!= fa
->tb_id
) {
1840 hlist_del_rcu(&fa
->fa_list
);
1841 alias_free_mem_rcu(fa
);
1845 /* record local slen */
1849 /* update leaf slen */
1852 if (hlist_empty(&n
->leaf
)) {
1853 put_child_root(pn
, n
->key
, NULL
);
1859 /* Caller must hold RTNL. */
1860 int fib_table_flush(struct net
*net
, struct fib_table
*tb
, bool flush_all
)
1862 struct trie
*t
= (struct trie
*)tb
->tb_data
;
1863 struct key_vector
*pn
= t
->kv
;
1864 unsigned long cindex
= 1;
1865 struct hlist_node
*tmp
;
1866 struct fib_alias
*fa
;
1869 /* walk trie in reverse order */
1871 unsigned char slen
= 0;
1872 struct key_vector
*n
;
1875 t_key pkey
= pn
->key
;
1877 /* cannot resize the trie vector */
1881 /* update the suffix to address pulled leaves */
1882 if (pn
->slen
> pn
->pos
)
1885 /* resize completed node */
1887 cindex
= get_index(pkey
, pn
);
1892 /* grab the next available node */
1893 n
= get_child(pn
, cindex
);
1898 /* record pn and cindex for leaf walking */
1900 cindex
= 1ul << n
->bits
;
1905 hlist_for_each_entry_safe(fa
, tmp
, &n
->leaf
, fa_list
) {
1906 struct fib_info
*fi
= fa
->fa_info
;
1908 if (!fi
|| tb
->tb_id
!= fa
->tb_id
||
1909 (!(fi
->fib_flags
& RTNH_F_DEAD
) &&
1910 !fib_props
[fa
->fa_type
].error
)) {
1915 /* Do not flush error routes if network namespace is
1916 * not being dismantled
1918 if (!flush_all
&& fib_props
[fa
->fa_type
].error
) {
1923 call_fib_entry_notifiers(net
, FIB_EVENT_ENTRY_DEL
,
1925 KEYLENGTH
- fa
->fa_slen
, fa
,
1927 hlist_del_rcu(&fa
->fa_list
);
1928 fib_release_info(fa
->fa_info
);
1929 alias_free_mem_rcu(fa
);
1933 /* update leaf slen */
1936 if (hlist_empty(&n
->leaf
)) {
1937 put_child_root(pn
, n
->key
, NULL
);
1942 pr_debug("trie_flush found=%d\n", found
);
1946 static void fib_leaf_notify(struct net
*net
, struct key_vector
*l
,
1947 struct fib_table
*tb
, struct notifier_block
*nb
)
1949 struct fib_alias
*fa
;
1951 hlist_for_each_entry_rcu(fa
, &l
->leaf
, fa_list
) {
1952 struct fib_info
*fi
= fa
->fa_info
;
1957 /* local and main table can share the same trie,
1958 * so don't notify twice for the same entry.
1960 if (tb
->tb_id
!= fa
->tb_id
)
1963 call_fib_entry_notifier(nb
, net
, FIB_EVENT_ENTRY_ADD
, l
->key
,
1964 KEYLENGTH
- fa
->fa_slen
, fa
);
1968 static void fib_table_notify(struct net
*net
, struct fib_table
*tb
,
1969 struct notifier_block
*nb
)
1971 struct trie
*t
= (struct trie
*)tb
->tb_data
;
1972 struct key_vector
*l
, *tp
= t
->kv
;
1975 while ((l
= leaf_walk_rcu(&tp
, key
)) != NULL
) {
1976 fib_leaf_notify(net
, l
, tb
, nb
);
1979 /* stop in case of wrap around */
1985 void fib_notify(struct net
*net
, struct notifier_block
*nb
)
1989 for (h
= 0; h
< FIB_TABLE_HASHSZ
; h
++) {
1990 struct hlist_head
*head
= &net
->ipv4
.fib_table_hash
[h
];
1991 struct fib_table
*tb
;
1993 hlist_for_each_entry_rcu(tb
, head
, tb_hlist
)
1994 fib_table_notify(net
, tb
, nb
);
1998 static void __trie_free_rcu(struct rcu_head
*head
)
2000 struct fib_table
*tb
= container_of(head
, struct fib_table
, rcu
);
2001 #ifdef CONFIG_IP_FIB_TRIE_STATS
2002 struct trie
*t
= (struct trie
*)tb
->tb_data
;
2004 if (tb
->tb_data
== tb
->__data
)
2005 free_percpu(t
->stats
);
2006 #endif /* CONFIG_IP_FIB_TRIE_STATS */
2010 void fib_free_table(struct fib_table
*tb
)
2012 call_rcu(&tb
->rcu
, __trie_free_rcu
);
2015 static int fn_trie_dump_leaf(struct key_vector
*l
, struct fib_table
*tb
,
2016 struct sk_buff
*skb
, struct netlink_callback
*cb
,
2017 struct fib_dump_filter
*filter
)
2019 unsigned int flags
= NLM_F_MULTI
;
2020 __be32 xkey
= htonl(l
->key
);
2021 struct fib_alias
*fa
;
2024 if (filter
->filter_set
)
2025 flags
|= NLM_F_DUMP_FILTERED
;
2030 /* rcu_read_lock is hold by caller */
2031 hlist_for_each_entry_rcu(fa
, &l
->leaf
, fa_list
) {
2037 if (tb
->tb_id
!= fa
->tb_id
)
2040 if (filter
->filter_set
) {
2041 if (filter
->rt_type
&& fa
->fa_type
!= filter
->rt_type
)
2044 if ((filter
->protocol
&&
2045 fa
->fa_info
->fib_protocol
!= filter
->protocol
))
2049 !fib_info_nh_uses_dev(fa
->fa_info
, filter
->dev
))
2053 err
= fib_dump_info(skb
, NETLINK_CB(cb
->skb
).portid
,
2054 cb
->nlh
->nlmsg_seq
, RTM_NEWROUTE
,
2055 tb
->tb_id
, fa
->fa_type
,
2056 xkey
, KEYLENGTH
- fa
->fa_slen
,
2057 fa
->fa_tos
, fa
->fa_info
, flags
);
2070 /* rcu_read_lock needs to be hold by caller from readside */
2071 int fib_table_dump(struct fib_table
*tb
, struct sk_buff
*skb
,
2072 struct netlink_callback
*cb
, struct fib_dump_filter
*filter
)
2074 struct trie
*t
= (struct trie
*)tb
->tb_data
;
2075 struct key_vector
*l
, *tp
= t
->kv
;
2076 /* Dump starting at last key.
2077 * Note: 0.0.0.0/0 (ie default) is first key.
2079 int count
= cb
->args
[2];
2080 t_key key
= cb
->args
[3];
2082 while ((l
= leaf_walk_rcu(&tp
, key
)) != NULL
) {
2085 err
= fn_trie_dump_leaf(l
, tb
, skb
, cb
, filter
);
2088 cb
->args
[2] = count
;
2095 memset(&cb
->args
[4], 0,
2096 sizeof(cb
->args
) - 4*sizeof(cb
->args
[0]));
2098 /* stop loop if key wrapped back to 0 */
2104 cb
->args
[2] = count
;
2109 void __init
fib_trie_init(void)
2111 fn_alias_kmem
= kmem_cache_create("ip_fib_alias",
2112 sizeof(struct fib_alias
),
2113 0, SLAB_PANIC
, NULL
);
2115 trie_leaf_kmem
= kmem_cache_create("ip_fib_trie",
2117 0, SLAB_PANIC
, NULL
);
2120 struct fib_table
*fib_trie_table(u32 id
, struct fib_table
*alias
)
2122 struct fib_table
*tb
;
2124 size_t sz
= sizeof(*tb
);
2127 sz
+= sizeof(struct trie
);
2129 tb
= kzalloc(sz
, GFP_KERNEL
);
2134 tb
->tb_num_default
= 0;
2135 tb
->tb_data
= (alias
? alias
->__data
: tb
->__data
);
2140 t
= (struct trie
*) tb
->tb_data
;
2141 t
->kv
[0].pos
= KEYLENGTH
;
2142 t
->kv
[0].slen
= KEYLENGTH
;
2143 #ifdef CONFIG_IP_FIB_TRIE_STATS
2144 t
->stats
= alloc_percpu(struct trie_use_stats
);
2154 #ifdef CONFIG_PROC_FS
2155 /* Depth first Trie walk iterator */
2156 struct fib_trie_iter
{
2157 struct seq_net_private p
;
2158 struct fib_table
*tb
;
2159 struct key_vector
*tnode
;
2164 static struct key_vector
*fib_trie_get_next(struct fib_trie_iter
*iter
)
2166 unsigned long cindex
= iter
->index
;
2167 struct key_vector
*pn
= iter
->tnode
;
2170 pr_debug("get_next iter={node=%p index=%d depth=%d}\n",
2171 iter
->tnode
, iter
->index
, iter
->depth
);
2173 while (!IS_TRIE(pn
)) {
2174 while (cindex
< child_length(pn
)) {
2175 struct key_vector
*n
= get_child_rcu(pn
, cindex
++);
2182 iter
->index
= cindex
;
2184 /* push down one level */
2193 /* Current node exhausted, pop back up */
2195 pn
= node_parent_rcu(pn
);
2196 cindex
= get_index(pkey
, pn
) + 1;
2200 /* record root node so further searches know we are done */
2207 static struct key_vector
*fib_trie_get_first(struct fib_trie_iter
*iter
,
2210 struct key_vector
*n
, *pn
;
2216 n
= rcu_dereference(pn
->tnode
[0]);
2233 static void trie_collect_stats(struct trie
*t
, struct trie_stat
*s
)
2235 struct key_vector
*n
;
2236 struct fib_trie_iter iter
;
2238 memset(s
, 0, sizeof(*s
));
2241 for (n
= fib_trie_get_first(&iter
, t
); n
; n
= fib_trie_get_next(&iter
)) {
2243 struct fib_alias
*fa
;
2246 s
->totdepth
+= iter
.depth
;
2247 if (iter
.depth
> s
->maxdepth
)
2248 s
->maxdepth
= iter
.depth
;
2250 hlist_for_each_entry_rcu(fa
, &n
->leaf
, fa_list
)
2254 if (n
->bits
< MAX_STAT_DEPTH
)
2255 s
->nodesizes
[n
->bits
]++;
2256 s
->nullpointers
+= tn_info(n
)->empty_children
;
2263 * This outputs /proc/net/fib_triestats
2265 static void trie_show_stats(struct seq_file
*seq
, struct trie_stat
*stat
)
2267 unsigned int i
, max
, pointers
, bytes
, avdepth
;
2270 avdepth
= stat
->totdepth
*100 / stat
->leaves
;
2274 seq_printf(seq
, "\tAver depth: %u.%02d\n",
2275 avdepth
/ 100, avdepth
% 100);
2276 seq_printf(seq
, "\tMax depth: %u\n", stat
->maxdepth
);
2278 seq_printf(seq
, "\tLeaves: %u\n", stat
->leaves
);
2279 bytes
= LEAF_SIZE
* stat
->leaves
;
2281 seq_printf(seq
, "\tPrefixes: %u\n", stat
->prefixes
);
2282 bytes
+= sizeof(struct fib_alias
) * stat
->prefixes
;
2284 seq_printf(seq
, "\tInternal nodes: %u\n\t", stat
->tnodes
);
2285 bytes
+= TNODE_SIZE(0) * stat
->tnodes
;
2287 max
= MAX_STAT_DEPTH
;
2288 while (max
> 0 && stat
->nodesizes
[max
-1] == 0)
2292 for (i
= 1; i
< max
; i
++)
2293 if (stat
->nodesizes
[i
] != 0) {
2294 seq_printf(seq
, " %u: %u", i
, stat
->nodesizes
[i
]);
2295 pointers
+= (1<<i
) * stat
->nodesizes
[i
];
2297 seq_putc(seq
, '\n');
2298 seq_printf(seq
, "\tPointers: %u\n", pointers
);
2300 bytes
+= sizeof(struct key_vector
*) * pointers
;
2301 seq_printf(seq
, "Null ptrs: %u\n", stat
->nullpointers
);
2302 seq_printf(seq
, "Total size: %u kB\n", (bytes
+ 1023) / 1024);
2305 #ifdef CONFIG_IP_FIB_TRIE_STATS
2306 static void trie_show_usage(struct seq_file
*seq
,
2307 const struct trie_use_stats __percpu
*stats
)
2309 struct trie_use_stats s
= { 0 };
2312 /* loop through all of the CPUs and gather up the stats */
2313 for_each_possible_cpu(cpu
) {
2314 const struct trie_use_stats
*pcpu
= per_cpu_ptr(stats
, cpu
);
2316 s
.gets
+= pcpu
->gets
;
2317 s
.backtrack
+= pcpu
->backtrack
;
2318 s
.semantic_match_passed
+= pcpu
->semantic_match_passed
;
2319 s
.semantic_match_miss
+= pcpu
->semantic_match_miss
;
2320 s
.null_node_hit
+= pcpu
->null_node_hit
;
2321 s
.resize_node_skipped
+= pcpu
->resize_node_skipped
;
2324 seq_printf(seq
, "\nCounters:\n---------\n");
2325 seq_printf(seq
, "gets = %u\n", s
.gets
);
2326 seq_printf(seq
, "backtracks = %u\n", s
.backtrack
);
2327 seq_printf(seq
, "semantic match passed = %u\n",
2328 s
.semantic_match_passed
);
2329 seq_printf(seq
, "semantic match miss = %u\n", s
.semantic_match_miss
);
2330 seq_printf(seq
, "null node hit= %u\n", s
.null_node_hit
);
2331 seq_printf(seq
, "skipped node resize = %u\n\n", s
.resize_node_skipped
);
2333 #endif /* CONFIG_IP_FIB_TRIE_STATS */
2335 static void fib_table_print(struct seq_file
*seq
, struct fib_table
*tb
)
2337 if (tb
->tb_id
== RT_TABLE_LOCAL
)
2338 seq_puts(seq
, "Local:\n");
2339 else if (tb
->tb_id
== RT_TABLE_MAIN
)
2340 seq_puts(seq
, "Main:\n");
2342 seq_printf(seq
, "Id %d:\n", tb
->tb_id
);
2346 static int fib_triestat_seq_show(struct seq_file
*seq
, void *v
)
2348 struct net
*net
= (struct net
*)seq
->private;
2352 "Basic info: size of leaf:"
2353 " %zd bytes, size of tnode: %zd bytes.\n",
2354 LEAF_SIZE
, TNODE_SIZE(0));
2356 for (h
= 0; h
< FIB_TABLE_HASHSZ
; h
++) {
2357 struct hlist_head
*head
= &net
->ipv4
.fib_table_hash
[h
];
2358 struct fib_table
*tb
;
2360 hlist_for_each_entry_rcu(tb
, head
, tb_hlist
) {
2361 struct trie
*t
= (struct trie
*) tb
->tb_data
;
2362 struct trie_stat stat
;
2367 fib_table_print(seq
, tb
);
2369 trie_collect_stats(t
, &stat
);
2370 trie_show_stats(seq
, &stat
);
2371 #ifdef CONFIG_IP_FIB_TRIE_STATS
2372 trie_show_usage(seq
, t
->stats
);
2380 static struct key_vector
*fib_trie_get_idx(struct seq_file
*seq
, loff_t pos
)
2382 struct fib_trie_iter
*iter
= seq
->private;
2383 struct net
*net
= seq_file_net(seq
);
2387 for (h
= 0; h
< FIB_TABLE_HASHSZ
; h
++) {
2388 struct hlist_head
*head
= &net
->ipv4
.fib_table_hash
[h
];
2389 struct fib_table
*tb
;
2391 hlist_for_each_entry_rcu(tb
, head
, tb_hlist
) {
2392 struct key_vector
*n
;
2394 for (n
= fib_trie_get_first(iter
,
2395 (struct trie
*) tb
->tb_data
);
2396 n
; n
= fib_trie_get_next(iter
))
2407 static void *fib_trie_seq_start(struct seq_file
*seq
, loff_t
*pos
)
2411 return fib_trie_get_idx(seq
, *pos
);
2414 static void *fib_trie_seq_next(struct seq_file
*seq
, void *v
, loff_t
*pos
)
2416 struct fib_trie_iter
*iter
= seq
->private;
2417 struct net
*net
= seq_file_net(seq
);
2418 struct fib_table
*tb
= iter
->tb
;
2419 struct hlist_node
*tb_node
;
2421 struct key_vector
*n
;
2424 /* next node in same table */
2425 n
= fib_trie_get_next(iter
);
2429 /* walk rest of this hash chain */
2430 h
= tb
->tb_id
& (FIB_TABLE_HASHSZ
- 1);
2431 while ((tb_node
= rcu_dereference(hlist_next_rcu(&tb
->tb_hlist
)))) {
2432 tb
= hlist_entry(tb_node
, struct fib_table
, tb_hlist
);
2433 n
= fib_trie_get_first(iter
, (struct trie
*) tb
->tb_data
);
2438 /* new hash chain */
2439 while (++h
< FIB_TABLE_HASHSZ
) {
2440 struct hlist_head
*head
= &net
->ipv4
.fib_table_hash
[h
];
2441 hlist_for_each_entry_rcu(tb
, head
, tb_hlist
) {
2442 n
= fib_trie_get_first(iter
, (struct trie
*) tb
->tb_data
);
2454 static void fib_trie_seq_stop(struct seq_file
*seq
, void *v
)
2460 static void seq_indent(struct seq_file
*seq
, int n
)
2466 static inline const char *rtn_scope(char *buf
, size_t len
, enum rt_scope_t s
)
2469 case RT_SCOPE_UNIVERSE
: return "universe";
2470 case RT_SCOPE_SITE
: return "site";
2471 case RT_SCOPE_LINK
: return "link";
2472 case RT_SCOPE_HOST
: return "host";
2473 case RT_SCOPE_NOWHERE
: return "nowhere";
2475 snprintf(buf
, len
, "scope=%d", s
);
2480 static const char *const rtn_type_names
[__RTN_MAX
] = {
2481 [RTN_UNSPEC
] = "UNSPEC",
2482 [RTN_UNICAST
] = "UNICAST",
2483 [RTN_LOCAL
] = "LOCAL",
2484 [RTN_BROADCAST
] = "BROADCAST",
2485 [RTN_ANYCAST
] = "ANYCAST",
2486 [RTN_MULTICAST
] = "MULTICAST",
2487 [RTN_BLACKHOLE
] = "BLACKHOLE",
2488 [RTN_UNREACHABLE
] = "UNREACHABLE",
2489 [RTN_PROHIBIT
] = "PROHIBIT",
2490 [RTN_THROW
] = "THROW",
2492 [RTN_XRESOLVE
] = "XRESOLVE",
2495 static inline const char *rtn_type(char *buf
, size_t len
, unsigned int t
)
2497 if (t
< __RTN_MAX
&& rtn_type_names
[t
])
2498 return rtn_type_names
[t
];
2499 snprintf(buf
, len
, "type %u", t
);
2503 /* Pretty print the trie */
2504 static int fib_trie_seq_show(struct seq_file
*seq
, void *v
)
2506 const struct fib_trie_iter
*iter
= seq
->private;
2507 struct key_vector
*n
= v
;
2509 if (IS_TRIE(node_parent_rcu(n
)))
2510 fib_table_print(seq
, iter
->tb
);
2513 __be32 prf
= htonl(n
->key
);
2515 seq_indent(seq
, iter
->depth
-1);
2516 seq_printf(seq
, " +-- %pI4/%zu %u %u %u\n",
2517 &prf
, KEYLENGTH
- n
->pos
- n
->bits
, n
->bits
,
2518 tn_info(n
)->full_children
,
2519 tn_info(n
)->empty_children
);
2521 __be32 val
= htonl(n
->key
);
2522 struct fib_alias
*fa
;
2524 seq_indent(seq
, iter
->depth
);
2525 seq_printf(seq
, " |-- %pI4\n", &val
);
2527 hlist_for_each_entry_rcu(fa
, &n
->leaf
, fa_list
) {
2528 char buf1
[32], buf2
[32];
2530 seq_indent(seq
, iter
->depth
+ 1);
2531 seq_printf(seq
, " /%zu %s %s",
2532 KEYLENGTH
- fa
->fa_slen
,
2533 rtn_scope(buf1
, sizeof(buf1
),
2534 fa
->fa_info
->fib_scope
),
2535 rtn_type(buf2
, sizeof(buf2
),
2538 seq_printf(seq
, " tos=%d", fa
->fa_tos
);
2539 seq_putc(seq
, '\n');
2546 static const struct seq_operations fib_trie_seq_ops
= {
2547 .start
= fib_trie_seq_start
,
2548 .next
= fib_trie_seq_next
,
2549 .stop
= fib_trie_seq_stop
,
2550 .show
= fib_trie_seq_show
,
2553 struct fib_route_iter
{
2554 struct seq_net_private p
;
2555 struct fib_table
*main_tb
;
2556 struct key_vector
*tnode
;
2561 static struct key_vector
*fib_route_get_idx(struct fib_route_iter
*iter
,
2564 struct key_vector
*l
, **tp
= &iter
->tnode
;
2567 /* use cached location of previously found key */
2568 if (iter
->pos
> 0 && pos
>= iter
->pos
) {
2577 while ((l
= leaf_walk_rcu(tp
, key
)) && (pos
-- > 0)) {
2582 /* handle unlikely case of a key wrap */
2588 iter
->key
= l
->key
; /* remember it */
2590 iter
->pos
= 0; /* forget it */
2595 static void *fib_route_seq_start(struct seq_file
*seq
, loff_t
*pos
)
2598 struct fib_route_iter
*iter
= seq
->private;
2599 struct fib_table
*tb
;
2604 tb
= fib_get_table(seq_file_net(seq
), RT_TABLE_MAIN
);
2609 t
= (struct trie
*)tb
->tb_data
;
2610 iter
->tnode
= t
->kv
;
2613 return fib_route_get_idx(iter
, *pos
);
2616 iter
->key
= KEY_MAX
;
2618 return SEQ_START_TOKEN
;
2621 static void *fib_route_seq_next(struct seq_file
*seq
, void *v
, loff_t
*pos
)
2623 struct fib_route_iter
*iter
= seq
->private;
2624 struct key_vector
*l
= NULL
;
2625 t_key key
= iter
->key
+ 1;
2629 /* only allow key of 0 for start of sequence */
2630 if ((v
== SEQ_START_TOKEN
) || key
)
2631 l
= leaf_walk_rcu(&iter
->tnode
, key
);
2643 static void fib_route_seq_stop(struct seq_file
*seq
, void *v
)
2649 static unsigned int fib_flag_trans(int type
, __be32 mask
, const struct fib_info
*fi
)
2651 unsigned int flags
= 0;
2653 if (type
== RTN_UNREACHABLE
|| type
== RTN_PROHIBIT
)
2655 if (fi
&& fi
->fib_nh
->fib_nh_gw4
)
2656 flags
|= RTF_GATEWAY
;
2657 if (mask
== htonl(0xFFFFFFFF))
2664 * This outputs /proc/net/route.
2665 * The format of the file is not supposed to be changed
2666 * and needs to be same as fib_hash output to avoid breaking
2669 static int fib_route_seq_show(struct seq_file
*seq
, void *v
)
2671 struct fib_route_iter
*iter
= seq
->private;
2672 struct fib_table
*tb
= iter
->main_tb
;
2673 struct fib_alias
*fa
;
2674 struct key_vector
*l
= v
;
2677 if (v
== SEQ_START_TOKEN
) {
2678 seq_printf(seq
, "%-127s\n", "Iface\tDestination\tGateway "
2679 "\tFlags\tRefCnt\tUse\tMetric\tMask\t\tMTU"
2684 prefix
= htonl(l
->key
);
2686 hlist_for_each_entry_rcu(fa
, &l
->leaf
, fa_list
) {
2687 const struct fib_info
*fi
= fa
->fa_info
;
2688 __be32 mask
= inet_make_mask(KEYLENGTH
- fa
->fa_slen
);
2689 unsigned int flags
= fib_flag_trans(fa
->fa_type
, mask
, fi
);
2691 if ((fa
->fa_type
== RTN_BROADCAST
) ||
2692 (fa
->fa_type
== RTN_MULTICAST
))
2695 if (fa
->tb_id
!= tb
->tb_id
)
2698 seq_setwidth(seq
, 127);
2702 "%s\t%08X\t%08X\t%04X\t%d\t%u\t"
2703 "%d\t%08X\t%d\t%u\t%u",
2704 fi
->fib_dev
? fi
->fib_dev
->name
: "*",
2706 fi
->fib_nh
->fib_nh_gw4
, flags
, 0, 0,
2710 fi
->fib_advmss
+ 40 : 0),
2715 "*\t%08X\t%08X\t%04X\t%d\t%u\t"
2716 "%d\t%08X\t%d\t%u\t%u",
2717 prefix
, 0, flags
, 0, 0, 0,
2726 static const struct seq_operations fib_route_seq_ops
= {
2727 .start
= fib_route_seq_start
,
2728 .next
= fib_route_seq_next
,
2729 .stop
= fib_route_seq_stop
,
2730 .show
= fib_route_seq_show
,
2733 int __net_init
fib_proc_init(struct net
*net
)
2735 if (!proc_create_net("fib_trie", 0444, net
->proc_net
, &fib_trie_seq_ops
,
2736 sizeof(struct fib_trie_iter
)))
2739 if (!proc_create_net_single("fib_triestat", 0444, net
->proc_net
,
2740 fib_triestat_seq_show
, NULL
))
2743 if (!proc_create_net("route", 0444, net
->proc_net
, &fib_route_seq_ops
,
2744 sizeof(struct fib_route_iter
)))
2750 remove_proc_entry("fib_triestat", net
->proc_net
);
2752 remove_proc_entry("fib_trie", net
->proc_net
);
2757 void __net_exit
fib_proc_exit(struct net
*net
)
2759 remove_proc_entry("fib_trie", net
->proc_net
);
2760 remove_proc_entry("fib_triestat", net
->proc_net
);
2761 remove_proc_entry("route", net
->proc_net
);
2764 #endif /* CONFIG_PROC_FS */