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 unsigned int fib_seq_sum(void)
89 unsigned int fib_seq = 0;
94 fib_seq += net->ipv4.fib_seq;
100 static ATOMIC_NOTIFIER_HEAD(fib_chain);
102 static int call_fib_notifier(struct notifier_block *nb, struct net *net,
103 enum fib_event_type event_type,
104 struct fib_notifier_info *info)
107 return nb->notifier_call(nb, event_type, info);
110 static void fib_rules_notify(struct net *net, struct notifier_block *nb,
111 enum fib_event_type event_type)
113 #ifdef CONFIG_IP_MULTIPLE_TABLES
114 struct fib_notifier_info info;
116 if (net->ipv4.fib_has_custom_rules)
117 call_fib_notifier(nb, net, event_type, &info);
121 static void fib_notify(struct net *net, struct notifier_block *nb,
122 enum fib_event_type event_type);
124 static int call_fib_entry_notifier(struct notifier_block *nb, struct net *net,
125 enum fib_event_type event_type, u32 dst,
126 int dst_len, struct fib_info *fi,
127 u8 tos, u8 type, u32 tb_id)
129 struct fib_entry_notifier_info info = {
137 return call_fib_notifier(nb, net, event_type, &info.info);
140 static bool fib_dump_is_consistent(struct notifier_block *nb,
141 void (*cb)(struct notifier_block *nb),
142 unsigned int fib_seq)
144 atomic_notifier_chain_register(&fib_chain, nb);
145 if (fib_seq == fib_seq_sum())
147 atomic_notifier_chain_unregister(&fib_chain, nb);
153 #define FIB_DUMP_MAX_RETRIES 5
154 int register_fib_notifier(struct notifier_block *nb,
155 void (*cb)(struct notifier_block *nb))
160 unsigned int fib_seq = fib_seq_sum();
163 /* Mutex semantics guarantee that every change done to
164 * FIB tries before we read the change sequence counter
165 * is now visible to us.
168 for_each_net_rcu(net) {
169 fib_rules_notify(net, nb, FIB_EVENT_RULE_ADD);
170 fib_notify(net, nb, FIB_EVENT_ENTRY_ADD);
174 if (fib_dump_is_consistent(nb, cb, fib_seq))
176 } while (++retries < FIB_DUMP_MAX_RETRIES);
180 EXPORT_SYMBOL(register_fib_notifier);
182 int unregister_fib_notifier(struct notifier_block *nb)
184 return atomic_notifier_chain_unregister(&fib_chain, nb);
186 EXPORT_SYMBOL(unregister_fib_notifier);
188 int call_fib_notifiers(struct net *net, enum fib_event_type event_type,
189 struct fib_notifier_info *info)
193 return atomic_notifier_call_chain(&fib_chain, event_type, info);
196 static int call_fib_entry_notifiers(struct net *net,
197 enum fib_event_type event_type, u32 dst,
198 int dst_len, struct fib_info *fi,
199 u8 tos, u8 type, u32 tb_id)
201 struct fib_entry_notifier_info info = {
209 return call_fib_notifiers(net, event_type, &info.info);
212 #define MAX_STAT_DEPTH 32
214 #define KEYLENGTH (8*sizeof(t_key))
215 #define KEY_MAX ((t_key)~0)
217 typedef unsigned int t_key;
219 #define IS_TRIE(n) ((n)->pos >= KEYLENGTH)
220 #define IS_TNODE(n) ((n)->bits)
221 #define IS_LEAF(n) (!(n)->bits)
225 unsigned char pos; /* 2log(KEYLENGTH) bits needed */
226 unsigned char bits; /* 2log(KEYLENGTH) bits needed */
229 /* This list pointer if valid if (pos | bits) == 0 (LEAF) */
230 struct hlist_head leaf;
231 /* This array is valid if (pos | bits) > 0 (TNODE) */
232 struct key_vector __rcu *tnode[0];
238 t_key empty_children; /* KEYLENGTH bits needed */
239 t_key full_children; /* KEYLENGTH bits needed */
240 struct key_vector __rcu *parent;
241 struct key_vector kv[1];
242 #define tn_bits kv[0].bits
245 #define TNODE_SIZE(n) offsetof(struct tnode, kv[0].tnode[n])
246 #define LEAF_SIZE TNODE_SIZE(1)
248 #ifdef CONFIG_IP_FIB_TRIE_STATS
249 struct trie_use_stats {
251 unsigned int backtrack;
252 unsigned int semantic_match_passed;
253 unsigned int semantic_match_miss;
254 unsigned int null_node_hit;
255 unsigned int resize_node_skipped;
260 unsigned int totdepth;
261 unsigned int maxdepth;
264 unsigned int nullpointers;
265 unsigned int prefixes;
266 unsigned int nodesizes[MAX_STAT_DEPTH];
270 struct key_vector kv[1];
271 #ifdef CONFIG_IP_FIB_TRIE_STATS
272 struct trie_use_stats __percpu *stats;
276 static struct key_vector *resize(struct trie *t, struct key_vector *tn);
277 static size_t tnode_free_size;
280 * synchronize_rcu after call_rcu for that many pages; it should be especially
281 * useful before resizing the root node with PREEMPT_NONE configs; the value was
282 * obtained experimentally, aiming to avoid visible slowdown.
284 static const int sync_pages = 128;
286 static struct kmem_cache *fn_alias_kmem __read_mostly;
287 static struct kmem_cache *trie_leaf_kmem __read_mostly;
289 static inline struct tnode *tn_info(struct key_vector *kv)
291 return container_of(kv, struct tnode, kv[0]);
294 /* caller must hold RTNL */
295 #define node_parent(tn) rtnl_dereference(tn_info(tn)->parent)
296 #define get_child(tn, i) rtnl_dereference((tn)->tnode[i])
298 /* caller must hold RCU read lock or RTNL */
299 #define node_parent_rcu(tn) rcu_dereference_rtnl(tn_info(tn)->parent)
300 #define get_child_rcu(tn, i) rcu_dereference_rtnl((tn)->tnode[i])
302 /* wrapper for rcu_assign_pointer */
303 static inline void node_set_parent(struct key_vector *n, struct key_vector *tp)
306 rcu_assign_pointer(tn_info(n)->parent, tp);
309 #define NODE_INIT_PARENT(n, p) RCU_INIT_POINTER(tn_info(n)->parent, p)
311 /* This provides us with the number of children in this node, in the case of a
312 * leaf this will return 0 meaning none of the children are accessible.
314 static inline unsigned long child_length(const struct key_vector *tn)
316 return (1ul << tn->bits) & ~(1ul);
319 #define get_cindex(key, kv) (((key) ^ (kv)->key) >> (kv)->pos)
321 static inline unsigned long get_index(t_key key, struct key_vector *kv)
323 unsigned long index = key ^ kv->key;
325 if ((BITS_PER_LONG <= KEYLENGTH) && (KEYLENGTH == kv->pos))
328 return index >> kv->pos;
331 /* To understand this stuff, an understanding of keys and all their bits is
332 * necessary. Every node in the trie has a key associated with it, but not
333 * all of the bits in that key are significant.
335 * Consider a node 'n' and its parent 'tp'.
337 * If n is a leaf, every bit in its key is significant. Its presence is
338 * necessitated by path compression, since during a tree traversal (when
339 * searching for a leaf - unless we are doing an insertion) we will completely
340 * ignore all skipped bits we encounter. Thus we need to verify, at the end of
341 * a potentially successful search, that we have indeed been walking the
344 * Note that we can never "miss" the correct key in the tree if present by
345 * following the wrong path. Path compression ensures that segments of the key
346 * that are the same for all keys with a given prefix are skipped, but the
347 * skipped part *is* identical for each node in the subtrie below the skipped
348 * bit! trie_insert() in this implementation takes care of that.
350 * if n is an internal node - a 'tnode' here, the various parts of its key
351 * have many different meanings.
354 * _________________________________________________________________
355 * | i | i | i | i | i | i | i | N | N | N | S | S | S | S | S | C |
356 * -----------------------------------------------------------------
357 * 31 30 29 28 27 26 25 24 23 22 21 20 19 18 17 16
359 * _________________________________________________________________
360 * | C | C | C | u | u | u | u | u | u | u | u | u | u | u | u | u |
361 * -----------------------------------------------------------------
362 * 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0
369 * First, let's just ignore the bits that come before the parent tp, that is
370 * the bits from (tp->pos + tp->bits) to 31. They are *known* but at this
371 * point we do not use them for anything.
373 * The bits from (tp->pos) to (tp->pos + tp->bits - 1) - "N", above - are the
374 * index into the parent's child array. That is, they will be used to find
375 * 'n' among tp's children.
377 * The bits from (n->pos + n->bits) to (tp->pos - 1) - "S" - are skipped bits
380 * All the bits we have seen so far are significant to the node n. The rest
381 * of the bits are really not needed or indeed known in n->key.
383 * The bits from (n->pos) to (n->pos + n->bits - 1) - "C" - are the index into
384 * n's child array, and will of course be different for each child.
386 * The rest of the bits, from 0 to (n->pos -1) - "u" - are completely unknown
390 static const int halve_threshold = 25;
391 static const int inflate_threshold = 50;
392 static const int halve_threshold_root = 15;
393 static const int inflate_threshold_root = 30;
395 static void __alias_free_mem(struct rcu_head *head)
397 struct fib_alias *fa = container_of(head, struct fib_alias, rcu);
398 kmem_cache_free(fn_alias_kmem, fa);
401 static inline void alias_free_mem_rcu(struct fib_alias *fa)
403 call_rcu(&fa->rcu, __alias_free_mem);
406 #define TNODE_KMALLOC_MAX \
407 ilog2((PAGE_SIZE - TNODE_SIZE(0)) / sizeof(struct key_vector *))
408 #define TNODE_VMALLOC_MAX \
409 ilog2((SIZE_MAX - TNODE_SIZE(0)) / sizeof(struct key_vector *))
411 static void __node_free_rcu(struct rcu_head *head)
413 struct tnode *n = container_of(head, struct tnode, rcu);
416 kmem_cache_free(trie_leaf_kmem, n);
421 #define node_free(n) call_rcu(&tn_info(n)->rcu, __node_free_rcu)
423 static struct tnode *tnode_alloc(int bits)
427 /* verify bits is within bounds */
428 if (bits > TNODE_VMALLOC_MAX)
431 /* determine size and verify it is non-zero and didn't overflow */
432 size = TNODE_SIZE(1ul << bits);
434 if (size <= PAGE_SIZE)
435 return kzalloc(size, GFP_KERNEL);
437 return vzalloc(size);
440 static inline void empty_child_inc(struct key_vector *n)
442 ++tn_info(n)->empty_children ? : ++tn_info(n)->full_children;
445 static inline void empty_child_dec(struct key_vector *n)
447 tn_info(n)->empty_children-- ? : tn_info(n)->full_children--;
450 static struct key_vector *leaf_new(t_key key, struct fib_alias *fa)
452 struct key_vector *l;
455 kv = kmem_cache_alloc(trie_leaf_kmem, GFP_KERNEL);
459 /* initialize key vector */
464 l->slen = fa->fa_slen;
466 /* link leaf to fib alias */
467 INIT_HLIST_HEAD(&l->leaf);
468 hlist_add_head(&fa->fa_list, &l->leaf);
473 static struct key_vector *tnode_new(t_key key, int pos, int bits)
475 unsigned int shift = pos + bits;
476 struct key_vector *tn;
479 /* verify bits and pos their msb bits clear and values are valid */
480 BUG_ON(!bits || (shift > KEYLENGTH));
482 tnode = tnode_alloc(bits);
486 pr_debug("AT %p s=%zu %zu\n", tnode, TNODE_SIZE(0),
487 sizeof(struct key_vector *) << bits);
489 if (bits == KEYLENGTH)
490 tnode->full_children = 1;
492 tnode->empty_children = 1ul << bits;
495 tn->key = (shift < KEYLENGTH) ? (key >> shift) << shift : 0;
503 /* Check whether a tnode 'n' is "full", i.e. it is an internal node
504 * and no bits are skipped. See discussion in dyntree paper p. 6
506 static inline int tnode_full(struct key_vector *tn, struct key_vector *n)
508 return n && ((n->pos + n->bits) == tn->pos) && IS_TNODE(n);
511 /* Add a child at position i overwriting the old value.
512 * Update the value of full_children and empty_children.
514 static void put_child(struct key_vector *tn, unsigned long i,
515 struct key_vector *n)
517 struct key_vector *chi = get_child(tn, i);
520 BUG_ON(i >= child_length(tn));
522 /* update emptyChildren, overflow into fullChildren */
528 /* update fullChildren */
529 wasfull = tnode_full(tn, chi);
530 isfull = tnode_full(tn, n);
532 if (wasfull && !isfull)
533 tn_info(tn)->full_children--;
534 else if (!wasfull && isfull)
535 tn_info(tn)->full_children++;
537 if (n && (tn->slen < n->slen))
540 rcu_assign_pointer(tn->tnode[i], n);
543 static void update_children(struct key_vector *tn)
547 /* update all of the child parent pointers */
548 for (i = child_length(tn); i;) {
549 struct key_vector *inode = get_child(tn, --i);
554 /* Either update the children of a tnode that
555 * already belongs to us or update the child
556 * to point to ourselves.
558 if (node_parent(inode) == tn)
559 update_children(inode);
561 node_set_parent(inode, tn);
565 static inline void put_child_root(struct key_vector *tp, t_key key,
566 struct key_vector *n)
569 rcu_assign_pointer(tp->tnode[0], n);
571 put_child(tp, get_index(key, tp), n);
574 static inline void tnode_free_init(struct key_vector *tn)
576 tn_info(tn)->rcu.next = NULL;
579 static inline void tnode_free_append(struct key_vector *tn,
580 struct key_vector *n)
582 tn_info(n)->rcu.next = tn_info(tn)->rcu.next;
583 tn_info(tn)->rcu.next = &tn_info(n)->rcu;
586 static void tnode_free(struct key_vector *tn)
588 struct callback_head *head = &tn_info(tn)->rcu;
592 tnode_free_size += TNODE_SIZE(1ul << tn->bits);
595 tn = container_of(head, struct tnode, rcu)->kv;
598 if (tnode_free_size >= PAGE_SIZE * sync_pages) {
604 static struct key_vector *replace(struct trie *t,
605 struct key_vector *oldtnode,
606 struct key_vector *tn)
608 struct key_vector *tp = node_parent(oldtnode);
611 /* setup the parent pointer out of and back into this node */
612 NODE_INIT_PARENT(tn, tp);
613 put_child_root(tp, tn->key, tn);
615 /* update all of the child parent pointers */
618 /* all pointers should be clean so we are done */
619 tnode_free(oldtnode);
621 /* resize children now that oldtnode is freed */
622 for (i = child_length(tn); i;) {
623 struct key_vector *inode = get_child(tn, --i);
625 /* resize child node */
626 if (tnode_full(tn, inode))
627 tn = resize(t, inode);
633 static struct key_vector *inflate(struct trie *t,
634 struct key_vector *oldtnode)
636 struct key_vector *tn;
640 pr_debug("In inflate\n");
642 tn = tnode_new(oldtnode->key, oldtnode->pos - 1, oldtnode->bits + 1);
646 /* prepare oldtnode to be freed */
647 tnode_free_init(oldtnode);
649 /* Assemble all of the pointers in our cluster, in this case that
650 * represents all of the pointers out of our allocated nodes that
651 * point to existing tnodes and the links between our allocated
654 for (i = child_length(oldtnode), m = 1u << tn->pos; i;) {
655 struct key_vector *inode = get_child(oldtnode, --i);
656 struct key_vector *node0, *node1;
663 /* A leaf or an internal node with skipped bits */
664 if (!tnode_full(oldtnode, inode)) {
665 put_child(tn, get_index(inode->key, tn), inode);
669 /* drop the node in the old tnode free list */
670 tnode_free_append(oldtnode, inode);
672 /* An internal node with two children */
673 if (inode->bits == 1) {
674 put_child(tn, 2 * i + 1, get_child(inode, 1));
675 put_child(tn, 2 * i, get_child(inode, 0));
679 /* We will replace this node 'inode' with two new
680 * ones, 'node0' and 'node1', each with half of the
681 * original children. The two new nodes will have
682 * a position one bit further down the key and this
683 * means that the "significant" part of their keys
684 * (see the discussion near the top of this file)
685 * will differ by one bit, which will be "0" in
686 * node0's key and "1" in node1's key. Since we are
687 * moving the key position by one step, the bit that
688 * we are moving away from - the bit at position
689 * (tn->pos) - is the one that will differ between
690 * node0 and node1. So... we synthesize that bit in the
693 node1 = tnode_new(inode->key | m, inode->pos, inode->bits - 1);
696 node0 = tnode_new(inode->key, inode->pos, inode->bits - 1);
698 tnode_free_append(tn, node1);
701 tnode_free_append(tn, node0);
703 /* populate child pointers in new nodes */
704 for (k = child_length(inode), j = k / 2; j;) {
705 put_child(node1, --j, get_child(inode, --k));
706 put_child(node0, j, get_child(inode, j));
707 put_child(node1, --j, get_child(inode, --k));
708 put_child(node0, j, get_child(inode, j));
711 /* link new nodes to parent */
712 NODE_INIT_PARENT(node1, tn);
713 NODE_INIT_PARENT(node0, tn);
715 /* link parent to nodes */
716 put_child(tn, 2 * i + 1, node1);
717 put_child(tn, 2 * i, node0);
720 /* setup the parent pointers into and out of this node */
721 return replace(t, oldtnode, tn);
723 /* all pointers should be clean so we are done */
729 static struct key_vector *halve(struct trie *t,
730 struct key_vector *oldtnode)
732 struct key_vector *tn;
735 pr_debug("In halve\n");
737 tn = tnode_new(oldtnode->key, oldtnode->pos + 1, oldtnode->bits - 1);
741 /* prepare oldtnode to be freed */
742 tnode_free_init(oldtnode);
744 /* Assemble all of the pointers in our cluster, in this case that
745 * represents all of the pointers out of our allocated nodes that
746 * point to existing tnodes and the links between our allocated
749 for (i = child_length(oldtnode); i;) {
750 struct key_vector *node1 = get_child(oldtnode, --i);
751 struct key_vector *node0 = get_child(oldtnode, --i);
752 struct key_vector *inode;
754 /* At least one of the children is empty */
755 if (!node1 || !node0) {
756 put_child(tn, i / 2, node1 ? : node0);
760 /* Two nonempty children */
761 inode = tnode_new(node0->key, oldtnode->pos, 1);
764 tnode_free_append(tn, inode);
766 /* initialize pointers out of node */
767 put_child(inode, 1, node1);
768 put_child(inode, 0, node0);
769 NODE_INIT_PARENT(inode, tn);
771 /* link parent to node */
772 put_child(tn, i / 2, inode);
775 /* setup the parent pointers into and out of this node */
776 return replace(t, oldtnode, tn);
778 /* all pointers should be clean so we are done */
784 static struct key_vector *collapse(struct trie *t,
785 struct key_vector *oldtnode)
787 struct key_vector *n, *tp;
790 /* scan the tnode looking for that one child that might still exist */
791 for (n = NULL, i = child_length(oldtnode); !n && i;)
792 n = get_child(oldtnode, --i);
794 /* compress one level */
795 tp = node_parent(oldtnode);
796 put_child_root(tp, oldtnode->key, n);
797 node_set_parent(n, tp);
805 static unsigned char update_suffix(struct key_vector *tn)
807 unsigned char slen = tn->pos;
808 unsigned long stride, i;
809 unsigned char slen_max;
811 /* only vector 0 can have a suffix length greater than or equal to
812 * tn->pos + tn->bits, the second highest node will have a suffix
813 * length at most of tn->pos + tn->bits - 1
815 slen_max = min_t(unsigned char, tn->pos + tn->bits - 1, tn->slen);
817 /* search though the list of children looking for nodes that might
818 * have a suffix greater than the one we currently have. This is
819 * why we start with a stride of 2 since a stride of 1 would
820 * represent the nodes with suffix length equal to tn->pos
822 for (i = 0, stride = 0x2ul ; i < child_length(tn); i += stride) {
823 struct key_vector *n = get_child(tn, i);
825 if (!n || (n->slen <= slen))
828 /* update stride and slen based on new value */
829 stride <<= (n->slen - slen);
833 /* stop searching if we have hit the maximum possible value */
834 if (slen >= slen_max)
843 /* From "Implementing a dynamic compressed trie" by Stefan Nilsson of
844 * the Helsinki University of Technology and Matti Tikkanen of Nokia
845 * Telecommunications, page 6:
846 * "A node is doubled if the ratio of non-empty children to all
847 * children in the *doubled* node is at least 'high'."
849 * 'high' in this instance is the variable 'inflate_threshold'. It
850 * is expressed as a percentage, so we multiply it with
851 * child_length() and instead of multiplying by 2 (since the
852 * child array will be doubled by inflate()) and multiplying
853 * the left-hand side by 100 (to handle the percentage thing) we
854 * multiply the left-hand side by 50.
856 * The left-hand side may look a bit weird: child_length(tn)
857 * - tn->empty_children is of course the number of non-null children
858 * in the current node. tn->full_children is the number of "full"
859 * children, that is non-null tnodes with a skip value of 0.
860 * All of those will be doubled in the resulting inflated tnode, so
861 * we just count them one extra time here.
863 * A clearer way to write this would be:
865 * to_be_doubled = tn->full_children;
866 * not_to_be_doubled = child_length(tn) - tn->empty_children -
869 * new_child_length = child_length(tn) * 2;
871 * new_fill_factor = 100 * (not_to_be_doubled + 2*to_be_doubled) /
873 * if (new_fill_factor >= inflate_threshold)
875 * ...and so on, tho it would mess up the while () loop.
878 * 100 * (not_to_be_doubled + 2*to_be_doubled) / new_child_length >=
882 * 100 * (not_to_be_doubled + 2*to_be_doubled) >=
883 * inflate_threshold * new_child_length
885 * expand not_to_be_doubled and to_be_doubled, and shorten:
886 * 100 * (child_length(tn) - tn->empty_children +
887 * tn->full_children) >= inflate_threshold * new_child_length
889 * expand new_child_length:
890 * 100 * (child_length(tn) - tn->empty_children +
891 * tn->full_children) >=
892 * inflate_threshold * child_length(tn) * 2
895 * 50 * (tn->full_children + child_length(tn) -
896 * tn->empty_children) >= inflate_threshold *
900 static inline bool should_inflate(struct key_vector *tp, struct key_vector *tn)
902 unsigned long used = child_length(tn);
903 unsigned long threshold = used;
905 /* Keep root node larger */
906 threshold *= IS_TRIE(tp) ? inflate_threshold_root : inflate_threshold;
907 used -= tn_info(tn)->empty_children;
908 used += tn_info(tn)->full_children;
910 /* if bits == KEYLENGTH then pos = 0, and will fail below */
912 return (used > 1) && tn->pos && ((50 * used) >= threshold);
915 static inline bool should_halve(struct key_vector *tp, struct key_vector *tn)
917 unsigned long used = child_length(tn);
918 unsigned long threshold = used;
920 /* Keep root node larger */
921 threshold *= IS_TRIE(tp) ? halve_threshold_root : halve_threshold;
922 used -= tn_info(tn)->empty_children;
924 /* if bits == KEYLENGTH then used = 100% on wrap, and will fail below */
926 return (used > 1) && (tn->bits > 1) && ((100 * used) < threshold);
929 static inline bool should_collapse(struct key_vector *tn)
931 unsigned long used = child_length(tn);
933 used -= tn_info(tn)->empty_children;
935 /* account for bits == KEYLENGTH case */
936 if ((tn->bits == KEYLENGTH) && tn_info(tn)->full_children)
939 /* One child or none, time to drop us from the trie */
944 static struct key_vector *resize(struct trie *t, struct key_vector *tn)
946 #ifdef CONFIG_IP_FIB_TRIE_STATS
947 struct trie_use_stats __percpu *stats = t->stats;
949 struct key_vector *tp = node_parent(tn);
950 unsigned long cindex = get_index(tn->key, tp);
951 int max_work = MAX_WORK;
953 pr_debug("In tnode_resize %p inflate_threshold=%d threshold=%d\n",
954 tn, inflate_threshold, halve_threshold);
956 /* track the tnode via the pointer from the parent instead of
957 * doing it ourselves. This way we can let RCU fully do its
958 * thing without us interfering
960 BUG_ON(tn != get_child(tp, cindex));
962 /* Double as long as the resulting node has a number of
963 * nonempty nodes that are above the threshold.
965 while (should_inflate(tp, tn) && max_work) {
968 #ifdef CONFIG_IP_FIB_TRIE_STATS
969 this_cpu_inc(stats->resize_node_skipped);
975 tn = get_child(tp, cindex);
978 /* update parent in case inflate failed */
979 tp = node_parent(tn);
981 /* Return if at least one inflate is run */
982 if (max_work != MAX_WORK)
985 /* Halve as long as the number of empty children in this
986 * node is above threshold.
988 while (should_halve(tp, tn) && max_work) {
991 #ifdef CONFIG_IP_FIB_TRIE_STATS
992 this_cpu_inc(stats->resize_node_skipped);
998 tn = get_child(tp, cindex);
1001 /* Only one child remains */
1002 if (should_collapse(tn))
1003 return collapse(t, tn);
1005 /* update parent in case halve failed */
1006 return node_parent(tn);
1009 static void node_pull_suffix(struct key_vector *tn, unsigned char slen)
1011 unsigned char node_slen = tn->slen;
1013 while ((node_slen > tn->pos) && (node_slen > slen)) {
1014 slen = update_suffix(tn);
1015 if (node_slen == slen)
1018 tn = node_parent(tn);
1019 node_slen = tn->slen;
1023 static void node_push_suffix(struct key_vector *tn, unsigned char slen)
1025 while (tn->slen < slen) {
1027 tn = node_parent(tn);
1031 /* rcu_read_lock needs to be hold by caller from readside */
1032 static struct key_vector *fib_find_node(struct trie *t,
1033 struct key_vector **tp, u32 key)
1035 struct key_vector *pn, *n = t->kv;
1036 unsigned long index = 0;
1040 n = get_child_rcu(n, index);
1045 index = get_cindex(key, n);
1047 /* This bit of code is a bit tricky but it combines multiple
1048 * checks into a single check. The prefix consists of the
1049 * prefix plus zeros for the bits in the cindex. The index
1050 * is the difference between the key and this value. From
1051 * this we can actually derive several pieces of data.
1052 * if (index >= (1ul << bits))
1053 * we have a mismatch in skip bits and failed
1055 * we know the value is cindex
1057 * This check is safe even if bits == KEYLENGTH due to the
1058 * fact that we can only allocate a node with 32 bits if a
1059 * long is greater than 32 bits.
1061 if (index >= (1ul << n->bits)) {
1066 /* keep searching until we find a perfect match leaf or NULL */
1067 } while (IS_TNODE(n));
1074 /* Return the first fib alias matching TOS with
1075 * priority less than or equal to PRIO.
1077 static struct fib_alias *fib_find_alias(struct hlist_head *fah, u8 slen,
1078 u8 tos, u32 prio, u32 tb_id)
1080 struct fib_alias *fa;
1085 hlist_for_each_entry(fa, fah, fa_list) {
1086 if (fa->fa_slen < slen)
1088 if (fa->fa_slen != slen)
1090 if (fa->tb_id > tb_id)
1092 if (fa->tb_id != tb_id)
1094 if (fa->fa_tos > tos)
1096 if (fa->fa_info->fib_priority >= prio || fa->fa_tos < tos)
1103 static void trie_rebalance(struct trie *t, struct key_vector *tn)
1105 while (!IS_TRIE(tn))
1109 static int fib_insert_node(struct trie *t, struct key_vector *tp,
1110 struct fib_alias *new, t_key key)
1112 struct key_vector *n, *l;
1114 l = leaf_new(key, new);
1118 /* retrieve child from parent node */
1119 n = get_child(tp, get_index(key, tp));
1121 /* Case 2: n is a LEAF or a TNODE and the key doesn't match.
1123 * Add a new tnode here
1124 * first tnode need some special handling
1125 * leaves us in position for handling as case 3
1128 struct key_vector *tn;
1130 tn = tnode_new(key, __fls(key ^ n->key), 1);
1134 /* initialize routes out of node */
1135 NODE_INIT_PARENT(tn, tp);
1136 put_child(tn, get_index(key, tn) ^ 1, n);
1138 /* start adding routes into the node */
1139 put_child_root(tp, key, tn);
1140 node_set_parent(n, tn);
1142 /* parent now has a NULL spot where the leaf can go */
1146 /* Case 3: n is NULL, and will just insert a new leaf */
1147 node_push_suffix(tp, new->fa_slen);
1148 NODE_INIT_PARENT(l, tp);
1149 put_child_root(tp, key, l);
1150 trie_rebalance(t, tp);
1159 static int fib_insert_alias(struct trie *t, struct key_vector *tp,
1160 struct key_vector *l, struct fib_alias *new,
1161 struct fib_alias *fa, t_key key)
1164 return fib_insert_node(t, tp, new, key);
1167 hlist_add_before_rcu(&new->fa_list, &fa->fa_list);
1169 struct fib_alias *last;
1171 hlist_for_each_entry(last, &l->leaf, fa_list) {
1172 if (new->fa_slen < last->fa_slen)
1174 if ((new->fa_slen == last->fa_slen) &&
1175 (new->tb_id > last->tb_id))
1181 hlist_add_behind_rcu(&new->fa_list, &fa->fa_list);
1183 hlist_add_head_rcu(&new->fa_list, &l->leaf);
1186 /* if we added to the tail node then we need to update slen */
1187 if (l->slen < new->fa_slen) {
1188 l->slen = new->fa_slen;
1189 node_push_suffix(tp, new->fa_slen);
1195 /* Caller must hold RTNL. */
1196 int fib_table_insert(struct net *net, struct fib_table *tb,
1197 struct fib_config *cfg)
1199 enum fib_event_type event = FIB_EVENT_ENTRY_ADD;
1200 struct trie *t = (struct trie *)tb->tb_data;
1201 struct fib_alias *fa, *new_fa;
1202 struct key_vector *l, *tp;
1203 u16 nlflags = NLM_F_EXCL;
1204 struct fib_info *fi;
1205 u8 plen = cfg->fc_dst_len;
1206 u8 slen = KEYLENGTH - plen;
1207 u8 tos = cfg->fc_tos;
1211 if (plen > KEYLENGTH)
1214 key = ntohl(cfg->fc_dst);
1216 pr_debug("Insert table=%u %08x/%d\n", tb->tb_id, key, plen);
1218 if ((plen < KEYLENGTH) && (key << plen))
1221 fi = fib_create_info(cfg);
1227 l = fib_find_node(t, &tp, key);
1228 fa = l ? fib_find_alias(&l->leaf, slen, tos, fi->fib_priority,
1231 /* Now fa, if non-NULL, points to the first fib alias
1232 * with the same keys [prefix,tos,priority], if such key already
1233 * exists or to the node before which we will insert new one.
1235 * If fa is NULL, we will need to allocate a new one and
1236 * insert to the tail of the section matching the suffix length
1240 if (fa && fa->fa_tos == tos &&
1241 fa->fa_info->fib_priority == fi->fib_priority) {
1242 struct fib_alias *fa_first, *fa_match;
1245 if (cfg->fc_nlflags & NLM_F_EXCL)
1248 nlflags &= ~NLM_F_EXCL;
1251 * 1. Find exact match for type, scope, fib_info to avoid
1253 * 2. Find next 'fa' (or head), NLM_F_APPEND inserts before it
1257 hlist_for_each_entry_from(fa, fa_list) {
1258 if ((fa->fa_slen != slen) ||
1259 (fa->tb_id != tb->tb_id) ||
1260 (fa->fa_tos != tos))
1262 if (fa->fa_info->fib_priority != fi->fib_priority)
1264 if (fa->fa_type == cfg->fc_type &&
1265 fa->fa_info == fi) {
1271 if (cfg->fc_nlflags & NLM_F_REPLACE) {
1272 struct fib_info *fi_drop;
1275 nlflags |= NLM_F_REPLACE;
1283 new_fa = kmem_cache_alloc(fn_alias_kmem, GFP_KERNEL);
1287 fi_drop = fa->fa_info;
1288 new_fa->fa_tos = fa->fa_tos;
1289 new_fa->fa_info = fi;
1290 new_fa->fa_type = cfg->fc_type;
1291 state = fa->fa_state;
1292 new_fa->fa_state = state & ~FA_S_ACCESSED;
1293 new_fa->fa_slen = fa->fa_slen;
1294 new_fa->tb_id = tb->tb_id;
1295 new_fa->fa_default = -1;
1297 call_fib_entry_notifiers(net, FIB_EVENT_ENTRY_REPLACE,
1299 new_fa->fa_tos, cfg->fc_type,
1301 rtmsg_fib(RTM_NEWROUTE, htonl(key), new_fa, plen,
1302 tb->tb_id, &cfg->fc_nlinfo, nlflags);
1304 hlist_replace_rcu(&fa->fa_list, &new_fa->fa_list);
1306 alias_free_mem_rcu(fa);
1308 fib_release_info(fi_drop);
1309 if (state & FA_S_ACCESSED)
1310 rt_cache_flush(cfg->fc_nlinfo.nl_net);
1314 /* Error if we find a perfect match which
1315 * uses the same scope, type, and nexthop
1321 if (cfg->fc_nlflags & NLM_F_APPEND) {
1322 event = FIB_EVENT_ENTRY_APPEND;
1323 nlflags |= NLM_F_APPEND;
1329 if (!(cfg->fc_nlflags & NLM_F_CREATE))
1332 nlflags |= NLM_F_CREATE;
1334 new_fa = kmem_cache_alloc(fn_alias_kmem, GFP_KERNEL);
1338 new_fa->fa_info = fi;
1339 new_fa->fa_tos = tos;
1340 new_fa->fa_type = cfg->fc_type;
1341 new_fa->fa_state = 0;
1342 new_fa->fa_slen = slen;
1343 new_fa->tb_id = tb->tb_id;
1344 new_fa->fa_default = -1;
1346 /* Insert new entry to the list. */
1347 err = fib_insert_alias(t, tp, l, new_fa, fa, key);
1349 goto out_free_new_fa;
1352 tb->tb_num_default++;
1354 rt_cache_flush(cfg->fc_nlinfo.nl_net);
1355 call_fib_entry_notifiers(net, event, key, plen, fi, tos, cfg->fc_type,
1357 rtmsg_fib(RTM_NEWROUTE, htonl(key), new_fa, plen, new_fa->tb_id,
1358 &cfg->fc_nlinfo, nlflags);
1363 kmem_cache_free(fn_alias_kmem, new_fa);
1365 fib_release_info(fi);
1370 static inline t_key prefix_mismatch(t_key key, struct key_vector *n)
1372 t_key prefix = n->key;
1374 return (key ^ prefix) & (prefix | -prefix);
1377 /* should be called with rcu_read_lock */
1378 int fib_table_lookup(struct fib_table *tb, const struct flowi4 *flp,
1379 struct fib_result *res, int fib_flags)
1381 struct trie *t = (struct trie *) tb->tb_data;
1382 #ifdef CONFIG_IP_FIB_TRIE_STATS
1383 struct trie_use_stats __percpu *stats = t->stats;
1385 const t_key key = ntohl(flp->daddr);
1386 struct key_vector *n, *pn;
1387 struct fib_alias *fa;
1388 unsigned long index;
1391 trace_fib_table_lookup(tb->tb_id, flp);
1396 n = get_child_rcu(pn, cindex);
1400 #ifdef CONFIG_IP_FIB_TRIE_STATS
1401 this_cpu_inc(stats->gets);
1404 /* Step 1: Travel to the longest prefix match in the trie */
1406 index = get_cindex(key, n);
1408 /* This bit of code is a bit tricky but it combines multiple
1409 * checks into a single check. The prefix consists of the
1410 * prefix plus zeros for the "bits" in the prefix. The index
1411 * is the difference between the key and this value. From
1412 * this we can actually derive several pieces of data.
1413 * if (index >= (1ul << bits))
1414 * we have a mismatch in skip bits and failed
1416 * we know the value is cindex
1418 * This check is safe even if bits == KEYLENGTH due to the
1419 * fact that we can only allocate a node with 32 bits if a
1420 * long is greater than 32 bits.
1422 if (index >= (1ul << n->bits))
1425 /* we have found a leaf. Prefixes have already been compared */
1429 /* only record pn and cindex if we are going to be chopping
1430 * bits later. Otherwise we are just wasting cycles.
1432 if (n->slen > n->pos) {
1437 n = get_child_rcu(n, index);
1442 /* Step 2: Sort out leaves and begin backtracing for longest prefix */
1444 /* record the pointer where our next node pointer is stored */
1445 struct key_vector __rcu **cptr = n->tnode;
1447 /* This test verifies that none of the bits that differ
1448 * between the key and the prefix exist in the region of
1449 * the lsb and higher in the prefix.
1451 if (unlikely(prefix_mismatch(key, n)) || (n->slen == n->pos))
1454 /* exit out and process leaf */
1455 if (unlikely(IS_LEAF(n)))
1458 /* Don't bother recording parent info. Since we are in
1459 * prefix match mode we will have to come back to wherever
1460 * we started this traversal anyway
1463 while ((n = rcu_dereference(*cptr)) == NULL) {
1465 #ifdef CONFIG_IP_FIB_TRIE_STATS
1467 this_cpu_inc(stats->null_node_hit);
1469 /* If we are at cindex 0 there are no more bits for
1470 * us to strip at this level so we must ascend back
1471 * up one level to see if there are any more bits to
1472 * be stripped there.
1475 t_key pkey = pn->key;
1477 /* If we don't have a parent then there is
1478 * nothing for us to do as we do not have any
1479 * further nodes to parse.
1483 #ifdef CONFIG_IP_FIB_TRIE_STATS
1484 this_cpu_inc(stats->backtrack);
1486 /* Get Child's index */
1487 pn = node_parent_rcu(pn);
1488 cindex = get_index(pkey, pn);
1491 /* strip the least significant bit from the cindex */
1492 cindex &= cindex - 1;
1494 /* grab pointer for next child node */
1495 cptr = &pn->tnode[cindex];
1500 /* this line carries forward the xor from earlier in the function */
1501 index = key ^ n->key;
1503 /* Step 3: Process the leaf, if that fails fall back to backtracing */
1504 hlist_for_each_entry_rcu(fa, &n->leaf, fa_list) {
1505 struct fib_info *fi = fa->fa_info;
1508 if ((BITS_PER_LONG > KEYLENGTH) || (fa->fa_slen < KEYLENGTH)) {
1509 if (index >= (1ul << fa->fa_slen))
1512 if (fa->fa_tos && fa->fa_tos != flp->flowi4_tos)
1516 if (fa->fa_info->fib_scope < flp->flowi4_scope)
1518 fib_alias_accessed(fa);
1519 err = fib_props[fa->fa_type].error;
1520 if (unlikely(err < 0)) {
1521 #ifdef CONFIG_IP_FIB_TRIE_STATS
1522 this_cpu_inc(stats->semantic_match_passed);
1526 if (fi->fib_flags & RTNH_F_DEAD)
1528 for (nhsel = 0; nhsel < fi->fib_nhs; nhsel++) {
1529 const struct fib_nh *nh = &fi->fib_nh[nhsel];
1530 struct in_device *in_dev = __in_dev_get_rcu(nh->nh_dev);
1532 if (nh->nh_flags & RTNH_F_DEAD)
1535 IN_DEV_IGNORE_ROUTES_WITH_LINKDOWN(in_dev) &&
1536 nh->nh_flags & RTNH_F_LINKDOWN &&
1537 !(fib_flags & FIB_LOOKUP_IGNORE_LINKSTATE))
1539 if (!(flp->flowi4_flags & FLOWI_FLAG_SKIP_NH_OIF)) {
1540 if (flp->flowi4_oif &&
1541 flp->flowi4_oif != nh->nh_oif)
1545 if (!(fib_flags & FIB_LOOKUP_NOREF))
1546 atomic_inc(&fi->fib_clntref);
1548 res->prefixlen = KEYLENGTH - fa->fa_slen;
1549 res->nh_sel = nhsel;
1550 res->type = fa->fa_type;
1551 res->scope = fi->fib_scope;
1554 res->fa_head = &n->leaf;
1555 #ifdef CONFIG_IP_FIB_TRIE_STATS
1556 this_cpu_inc(stats->semantic_match_passed);
1558 trace_fib_table_lookup_nh(nh);
1563 #ifdef CONFIG_IP_FIB_TRIE_STATS
1564 this_cpu_inc(stats->semantic_match_miss);
1568 EXPORT_SYMBOL_GPL(fib_table_lookup);
1570 static void fib_remove_alias(struct trie *t, struct key_vector *tp,
1571 struct key_vector *l, struct fib_alias *old)
1573 /* record the location of the previous list_info entry */
1574 struct hlist_node **pprev = old->fa_list.pprev;
1575 struct fib_alias *fa = hlist_entry(pprev, typeof(*fa), fa_list.next);
1577 /* remove the fib_alias from the list */
1578 hlist_del_rcu(&old->fa_list);
1580 /* if we emptied the list this leaf will be freed and we can sort
1581 * out parent suffix lengths as a part of trie_rebalance
1583 if (hlist_empty(&l->leaf)) {
1584 if (tp->slen == l->slen)
1585 node_pull_suffix(tp, tp->pos);
1586 put_child_root(tp, l->key, NULL);
1588 trie_rebalance(t, tp);
1592 /* only access fa if it is pointing at the last valid hlist_node */
1596 /* update the trie with the latest suffix length */
1597 l->slen = fa->fa_slen;
1598 node_pull_suffix(tp, fa->fa_slen);
1601 /* Caller must hold RTNL. */
1602 int fib_table_delete(struct net *net, struct fib_table *tb,
1603 struct fib_config *cfg)
1605 struct trie *t = (struct trie *) tb->tb_data;
1606 struct fib_alias *fa, *fa_to_delete;
1607 struct key_vector *l, *tp;
1608 u8 plen = cfg->fc_dst_len;
1609 u8 slen = KEYLENGTH - plen;
1610 u8 tos = cfg->fc_tos;
1613 if (plen > KEYLENGTH)
1616 key = ntohl(cfg->fc_dst);
1618 if ((plen < KEYLENGTH) && (key << plen))
1621 l = fib_find_node(t, &tp, key);
1625 fa = fib_find_alias(&l->leaf, slen, tos, 0, tb->tb_id);
1629 pr_debug("Deleting %08x/%d tos=%d t=%p\n", key, plen, tos, t);
1631 fa_to_delete = NULL;
1632 hlist_for_each_entry_from(fa, fa_list) {
1633 struct fib_info *fi = fa->fa_info;
1635 if ((fa->fa_slen != slen) ||
1636 (fa->tb_id != tb->tb_id) ||
1637 (fa->fa_tos != tos))
1640 if ((!cfg->fc_type || fa->fa_type == cfg->fc_type) &&
1641 (cfg->fc_scope == RT_SCOPE_NOWHERE ||
1642 fa->fa_info->fib_scope == cfg->fc_scope) &&
1643 (!cfg->fc_prefsrc ||
1644 fi->fib_prefsrc == cfg->fc_prefsrc) &&
1645 (!cfg->fc_protocol ||
1646 fi->fib_protocol == cfg->fc_protocol) &&
1647 fib_nh_match(cfg, fi) == 0) {
1656 call_fib_entry_notifiers(net, FIB_EVENT_ENTRY_DEL, key, plen,
1657 fa_to_delete->fa_info, tos,
1658 fa_to_delete->fa_type, tb->tb_id);
1659 rtmsg_fib(RTM_DELROUTE, htonl(key), fa_to_delete, plen, tb->tb_id,
1660 &cfg->fc_nlinfo, 0);
1663 tb->tb_num_default--;
1665 fib_remove_alias(t, tp, l, fa_to_delete);
1667 if (fa_to_delete->fa_state & FA_S_ACCESSED)
1668 rt_cache_flush(cfg->fc_nlinfo.nl_net);
1670 fib_release_info(fa_to_delete->fa_info);
1671 alias_free_mem_rcu(fa_to_delete);
1675 /* Scan for the next leaf starting at the provided key value */
1676 static struct key_vector *leaf_walk_rcu(struct key_vector **tn, t_key key)
1678 struct key_vector *pn, *n = *tn;
1679 unsigned long cindex;
1681 /* this loop is meant to try and find the key in the trie */
1683 /* record parent and next child index */
1685 cindex = (key > pn->key) ? get_index(key, pn) : 0;
1687 if (cindex >> pn->bits)
1690 /* descend into the next child */
1691 n = get_child_rcu(pn, cindex++);
1695 /* guarantee forward progress on the keys */
1696 if (IS_LEAF(n) && (n->key >= key))
1698 } while (IS_TNODE(n));
1700 /* this loop will search for the next leaf with a greater key */
1701 while (!IS_TRIE(pn)) {
1702 /* if we exhausted the parent node we will need to climb */
1703 if (cindex >= (1ul << pn->bits)) {
1704 t_key pkey = pn->key;
1706 pn = node_parent_rcu(pn);
1707 cindex = get_index(pkey, pn) + 1;
1711 /* grab the next available node */
1712 n = get_child_rcu(pn, cindex++);
1716 /* no need to compare keys since we bumped the index */
1720 /* Rescan start scanning in new node */
1726 return NULL; /* Root of trie */
1728 /* if we are at the limit for keys just return NULL for the tnode */
1733 static void fib_trie_free(struct fib_table *tb)
1735 struct trie *t = (struct trie *)tb->tb_data;
1736 struct key_vector *pn = t->kv;
1737 unsigned long cindex = 1;
1738 struct hlist_node *tmp;
1739 struct fib_alias *fa;
1741 /* walk trie in reverse order and free everything */
1743 struct key_vector *n;
1746 t_key pkey = pn->key;
1752 pn = node_parent(pn);
1754 /* drop emptied tnode */
1755 put_child_root(pn, n->key, NULL);
1758 cindex = get_index(pkey, pn);
1763 /* grab the next available node */
1764 n = get_child(pn, cindex);
1769 /* record pn and cindex for leaf walking */
1771 cindex = 1ul << n->bits;
1776 hlist_for_each_entry_safe(fa, tmp, &n->leaf, fa_list) {
1777 hlist_del_rcu(&fa->fa_list);
1778 alias_free_mem_rcu(fa);
1781 put_child_root(pn, n->key, NULL);
1785 #ifdef CONFIG_IP_FIB_TRIE_STATS
1786 free_percpu(t->stats);
1791 struct fib_table *fib_trie_unmerge(struct fib_table *oldtb)
1793 struct trie *ot = (struct trie *)oldtb->tb_data;
1794 struct key_vector *l, *tp = ot->kv;
1795 struct fib_table *local_tb;
1796 struct fib_alias *fa;
1800 if (oldtb->tb_data == oldtb->__data)
1803 local_tb = fib_trie_table(RT_TABLE_LOCAL, NULL);
1807 lt = (struct trie *)local_tb->tb_data;
1809 while ((l = leaf_walk_rcu(&tp, key)) != NULL) {
1810 struct key_vector *local_l = NULL, *local_tp;
1812 hlist_for_each_entry_rcu(fa, &l->leaf, fa_list) {
1813 struct fib_alias *new_fa;
1815 if (local_tb->tb_id != fa->tb_id)
1818 /* clone fa for new local table */
1819 new_fa = kmem_cache_alloc(fn_alias_kmem, GFP_KERNEL);
1823 memcpy(new_fa, fa, sizeof(*fa));
1825 /* insert clone into table */
1827 local_l = fib_find_node(lt, &local_tp, l->key);
1829 if (fib_insert_alias(lt, local_tp, local_l, new_fa,
1831 kmem_cache_free(fn_alias_kmem, new_fa);
1836 /* stop loop if key wrapped back to 0 */
1844 fib_trie_free(local_tb);
1849 /* Caller must hold RTNL */
1850 void fib_table_flush_external(struct fib_table *tb)
1852 struct trie *t = (struct trie *)tb->tb_data;
1853 struct key_vector *pn = t->kv;
1854 unsigned long cindex = 1;
1855 struct hlist_node *tmp;
1856 struct fib_alias *fa;
1858 /* walk trie in reverse order */
1860 unsigned char slen = 0;
1861 struct key_vector *n;
1864 t_key pkey = pn->key;
1866 /* cannot resize the trie vector */
1870 /* update the suffix to address pulled leaves */
1871 if (pn->slen > pn->pos)
1874 /* resize completed node */
1876 cindex = get_index(pkey, pn);
1881 /* grab the next available node */
1882 n = get_child(pn, cindex);
1887 /* record pn and cindex for leaf walking */
1889 cindex = 1ul << n->bits;
1894 hlist_for_each_entry_safe(fa, tmp, &n->leaf, fa_list) {
1895 /* if alias was cloned to local then we just
1896 * need to remove the local copy from main
1898 if (tb->tb_id != fa->tb_id) {
1899 hlist_del_rcu(&fa->fa_list);
1900 alias_free_mem_rcu(fa);
1904 /* record local slen */
1908 /* update leaf slen */
1911 if (hlist_empty(&n->leaf)) {
1912 put_child_root(pn, n->key, NULL);
1918 /* Caller must hold RTNL. */
1919 int fib_table_flush(struct net *net, struct fib_table *tb)
1921 struct trie *t = (struct trie *)tb->tb_data;
1922 struct key_vector *pn = t->kv;
1923 unsigned long cindex = 1;
1924 struct hlist_node *tmp;
1925 struct fib_alias *fa;
1928 /* walk trie in reverse order */
1930 unsigned char slen = 0;
1931 struct key_vector *n;
1934 t_key pkey = pn->key;
1936 /* cannot resize the trie vector */
1940 /* update the suffix to address pulled leaves */
1941 if (pn->slen > pn->pos)
1944 /* resize completed node */
1946 cindex = get_index(pkey, pn);
1951 /* grab the next available node */
1952 n = get_child(pn, cindex);
1957 /* record pn and cindex for leaf walking */
1959 cindex = 1ul << n->bits;
1964 hlist_for_each_entry_safe(fa, tmp, &n->leaf, fa_list) {
1965 struct fib_info *fi = fa->fa_info;
1967 if (!fi || !(fi->fib_flags & RTNH_F_DEAD) ||
1968 tb->tb_id != fa->tb_id) {
1973 call_fib_entry_notifiers(net, FIB_EVENT_ENTRY_DEL,
1975 KEYLENGTH - fa->fa_slen,
1976 fi, fa->fa_tos, fa->fa_type,
1978 hlist_del_rcu(&fa->fa_list);
1979 fib_release_info(fa->fa_info);
1980 alias_free_mem_rcu(fa);
1984 /* update leaf slen */
1987 if (hlist_empty(&n->leaf)) {
1988 put_child_root(pn, n->key, NULL);
1993 pr_debug("trie_flush found=%d\n", found);
1997 static void fib_leaf_notify(struct net *net, struct key_vector *l,
1998 struct fib_table *tb, struct notifier_block *nb,
1999 enum fib_event_type event_type)
2001 struct fib_alias *fa;
2003 hlist_for_each_entry_rcu(fa, &l->leaf, fa_list) {
2004 struct fib_info *fi = fa->fa_info;
2009 /* local and main table can share the same trie,
2010 * so don't notify twice for the same entry.
2012 if (tb->tb_id != fa->tb_id)
2015 call_fib_entry_notifier(nb, net, event_type, l->key,
2016 KEYLENGTH - fa->fa_slen, fi, fa->fa_tos,
2017 fa->fa_type, fa->tb_id);
2021 static void fib_table_notify(struct net *net, struct fib_table *tb,
2022 struct notifier_block *nb,
2023 enum fib_event_type event_type)
2025 struct trie *t = (struct trie *)tb->tb_data;
2026 struct key_vector *l, *tp = t->kv;
2029 while ((l = leaf_walk_rcu(&tp, key)) != NULL) {
2030 fib_leaf_notify(net, l, tb, nb, event_type);
2033 /* stop in case of wrap around */
2039 static void fib_notify(struct net *net, struct notifier_block *nb,
2040 enum fib_event_type event_type)
2044 for (h = 0; h < FIB_TABLE_HASHSZ; h++) {
2045 struct hlist_head *head = &net->ipv4.fib_table_hash[h];
2046 struct fib_table *tb;
2048 hlist_for_each_entry_rcu(tb, head, tb_hlist)
2049 fib_table_notify(net, tb, nb, event_type);
2053 static void __trie_free_rcu(struct rcu_head *head)
2055 struct fib_table *tb = container_of(head, struct fib_table, rcu);
2056 #ifdef CONFIG_IP_FIB_TRIE_STATS
2057 struct trie *t = (struct trie *)tb->tb_data;
2059 if (tb->tb_data == tb->__data)
2060 free_percpu(t->stats);
2061 #endif /* CONFIG_IP_FIB_TRIE_STATS */
2065 void fib_free_table(struct fib_table *tb)
2067 call_rcu(&tb->rcu, __trie_free_rcu);
2070 static int fn_trie_dump_leaf(struct key_vector *l, struct fib_table *tb,
2071 struct sk_buff *skb, struct netlink_callback *cb)
2073 __be32 xkey = htonl(l->key);
2074 struct fib_alias *fa;
2080 /* rcu_read_lock is hold by caller */
2081 hlist_for_each_entry_rcu(fa, &l->leaf, fa_list) {
2087 if (tb->tb_id != fa->tb_id) {
2092 if (fib_dump_info(skb, NETLINK_CB(cb->skb).portid,
2098 KEYLENGTH - fa->fa_slen,
2100 fa->fa_info, NLM_F_MULTI) < 0) {
2111 /* rcu_read_lock needs to be hold by caller from readside */
2112 int fib_table_dump(struct fib_table *tb, struct sk_buff *skb,
2113 struct netlink_callback *cb)
2115 struct trie *t = (struct trie *)tb->tb_data;
2116 struct key_vector *l, *tp = t->kv;
2117 /* Dump starting at last key.
2118 * Note: 0.0.0.0/0 (ie default) is first key.
2120 int count = cb->args[2];
2121 t_key key = cb->args[3];
2123 while ((l = leaf_walk_rcu(&tp, key)) != NULL) {
2124 if (fn_trie_dump_leaf(l, tb, skb, cb) < 0) {
2126 cb->args[2] = count;
2133 memset(&cb->args[4], 0,
2134 sizeof(cb->args) - 4*sizeof(cb->args[0]));
2136 /* stop loop if key wrapped back to 0 */
2142 cb->args[2] = count;
2147 void __init fib_trie_init(void)
2149 fn_alias_kmem = kmem_cache_create("ip_fib_alias",
2150 sizeof(struct fib_alias),
2151 0, SLAB_PANIC, NULL);
2153 trie_leaf_kmem = kmem_cache_create("ip_fib_trie",
2155 0, SLAB_PANIC, NULL);
2158 struct fib_table *fib_trie_table(u32 id, struct fib_table *alias)
2160 struct fib_table *tb;
2162 size_t sz = sizeof(*tb);
2165 sz += sizeof(struct trie);
2167 tb = kzalloc(sz, GFP_KERNEL);
2172 tb->tb_num_default = 0;
2173 tb->tb_data = (alias ? alias->__data : tb->__data);
2178 t = (struct trie *) tb->tb_data;
2179 t->kv[0].pos = KEYLENGTH;
2180 t->kv[0].slen = KEYLENGTH;
2181 #ifdef CONFIG_IP_FIB_TRIE_STATS
2182 t->stats = alloc_percpu(struct trie_use_stats);
2192 #ifdef CONFIG_PROC_FS
2193 /* Depth first Trie walk iterator */
2194 struct fib_trie_iter {
2195 struct seq_net_private p;
2196 struct fib_table *tb;
2197 struct key_vector *tnode;
2202 static struct key_vector *fib_trie_get_next(struct fib_trie_iter *iter)
2204 unsigned long cindex = iter->index;
2205 struct key_vector *pn = iter->tnode;
2208 pr_debug("get_next iter={node=%p index=%d depth=%d}\n",
2209 iter->tnode, iter->index, iter->depth);
2211 while (!IS_TRIE(pn)) {
2212 while (cindex < child_length(pn)) {
2213 struct key_vector *n = get_child_rcu(pn, cindex++);
2220 iter->index = cindex;
2222 /* push down one level */
2231 /* Current node exhausted, pop back up */
2233 pn = node_parent_rcu(pn);
2234 cindex = get_index(pkey, pn) + 1;
2238 /* record root node so further searches know we are done */
2245 static struct key_vector *fib_trie_get_first(struct fib_trie_iter *iter,
2248 struct key_vector *n, *pn;
2254 n = rcu_dereference(pn->tnode[0]);
2271 static void trie_collect_stats(struct trie *t, struct trie_stat *s)
2273 struct key_vector *n;
2274 struct fib_trie_iter iter;
2276 memset(s, 0, sizeof(*s));
2279 for (n = fib_trie_get_first(&iter, t); n; n = fib_trie_get_next(&iter)) {
2281 struct fib_alias *fa;
2284 s->totdepth += iter.depth;
2285 if (iter.depth > s->maxdepth)
2286 s->maxdepth = iter.depth;
2288 hlist_for_each_entry_rcu(fa, &n->leaf, fa_list)
2292 if (n->bits < MAX_STAT_DEPTH)
2293 s->nodesizes[n->bits]++;
2294 s->nullpointers += tn_info(n)->empty_children;
2301 * This outputs /proc/net/fib_triestats
2303 static void trie_show_stats(struct seq_file *seq, struct trie_stat *stat)
2305 unsigned int i, max, pointers, bytes, avdepth;
2308 avdepth = stat->totdepth*100 / stat->leaves;
2312 seq_printf(seq, "\tAver depth: %u.%02d\n",
2313 avdepth / 100, avdepth % 100);
2314 seq_printf(seq, "\tMax depth: %u\n", stat->maxdepth);
2316 seq_printf(seq, "\tLeaves: %u\n", stat->leaves);
2317 bytes = LEAF_SIZE * stat->leaves;
2319 seq_printf(seq, "\tPrefixes: %u\n", stat->prefixes);
2320 bytes += sizeof(struct fib_alias) * stat->prefixes;
2322 seq_printf(seq, "\tInternal nodes: %u\n\t", stat->tnodes);
2323 bytes += TNODE_SIZE(0) * stat->tnodes;
2325 max = MAX_STAT_DEPTH;
2326 while (max > 0 && stat->nodesizes[max-1] == 0)
2330 for (i = 1; i < max; i++)
2331 if (stat->nodesizes[i] != 0) {
2332 seq_printf(seq, " %u: %u", i, stat->nodesizes[i]);
2333 pointers += (1<<i) * stat->nodesizes[i];
2335 seq_putc(seq, '\n');
2336 seq_printf(seq, "\tPointers: %u\n", pointers);
2338 bytes += sizeof(struct key_vector *) * pointers;
2339 seq_printf(seq, "Null ptrs: %u\n", stat->nullpointers);
2340 seq_printf(seq, "Total size: %u kB\n", (bytes + 1023) / 1024);
2343 #ifdef CONFIG_IP_FIB_TRIE_STATS
2344 static void trie_show_usage(struct seq_file *seq,
2345 const struct trie_use_stats __percpu *stats)
2347 struct trie_use_stats s = { 0 };
2350 /* loop through all of the CPUs and gather up the stats */
2351 for_each_possible_cpu(cpu) {
2352 const struct trie_use_stats *pcpu = per_cpu_ptr(stats, cpu);
2354 s.gets += pcpu->gets;
2355 s.backtrack += pcpu->backtrack;
2356 s.semantic_match_passed += pcpu->semantic_match_passed;
2357 s.semantic_match_miss += pcpu->semantic_match_miss;
2358 s.null_node_hit += pcpu->null_node_hit;
2359 s.resize_node_skipped += pcpu->resize_node_skipped;
2362 seq_printf(seq, "\nCounters:\n---------\n");
2363 seq_printf(seq, "gets = %u\n", s.gets);
2364 seq_printf(seq, "backtracks = %u\n", s.backtrack);
2365 seq_printf(seq, "semantic match passed = %u\n",
2366 s.semantic_match_passed);
2367 seq_printf(seq, "semantic match miss = %u\n", s.semantic_match_miss);
2368 seq_printf(seq, "null node hit= %u\n", s.null_node_hit);
2369 seq_printf(seq, "skipped node resize = %u\n\n", s.resize_node_skipped);
2371 #endif /* CONFIG_IP_FIB_TRIE_STATS */
2373 static void fib_table_print(struct seq_file *seq, struct fib_table *tb)
2375 if (tb->tb_id == RT_TABLE_LOCAL)
2376 seq_puts(seq, "Local:\n");
2377 else if (tb->tb_id == RT_TABLE_MAIN)
2378 seq_puts(seq, "Main:\n");
2380 seq_printf(seq, "Id %d:\n", tb->tb_id);
2384 static int fib_triestat_seq_show(struct seq_file *seq, void *v)
2386 struct net *net = (struct net *)seq->private;
2390 "Basic info: size of leaf:"
2391 " %zd bytes, size of tnode: %zd bytes.\n",
2392 LEAF_SIZE, TNODE_SIZE(0));
2394 for (h = 0; h < FIB_TABLE_HASHSZ; h++) {
2395 struct hlist_head *head = &net->ipv4.fib_table_hash[h];
2396 struct fib_table *tb;
2398 hlist_for_each_entry_rcu(tb, head, tb_hlist) {
2399 struct trie *t = (struct trie *) tb->tb_data;
2400 struct trie_stat stat;
2405 fib_table_print(seq, tb);
2407 trie_collect_stats(t, &stat);
2408 trie_show_stats(seq, &stat);
2409 #ifdef CONFIG_IP_FIB_TRIE_STATS
2410 trie_show_usage(seq, t->stats);
2418 static int fib_triestat_seq_open(struct inode *inode, struct file *file)
2420 return single_open_net(inode, file, fib_triestat_seq_show);
2423 static const struct file_operations fib_triestat_fops = {
2424 .owner = THIS_MODULE,
2425 .open = fib_triestat_seq_open,
2427 .llseek = seq_lseek,
2428 .release = single_release_net,
2431 static struct key_vector *fib_trie_get_idx(struct seq_file *seq, loff_t pos)
2433 struct fib_trie_iter *iter = seq->private;
2434 struct net *net = seq_file_net(seq);
2438 for (h = 0; h < FIB_TABLE_HASHSZ; h++) {
2439 struct hlist_head *head = &net->ipv4.fib_table_hash[h];
2440 struct fib_table *tb;
2442 hlist_for_each_entry_rcu(tb, head, tb_hlist) {
2443 struct key_vector *n;
2445 for (n = fib_trie_get_first(iter,
2446 (struct trie *) tb->tb_data);
2447 n; n = fib_trie_get_next(iter))
2458 static void *fib_trie_seq_start(struct seq_file *seq, loff_t *pos)
2462 return fib_trie_get_idx(seq, *pos);
2465 static void *fib_trie_seq_next(struct seq_file *seq, void *v, loff_t *pos)
2467 struct fib_trie_iter *iter = seq->private;
2468 struct net *net = seq_file_net(seq);
2469 struct fib_table *tb = iter->tb;
2470 struct hlist_node *tb_node;
2472 struct key_vector *n;
2475 /* next node in same table */
2476 n = fib_trie_get_next(iter);
2480 /* walk rest of this hash chain */
2481 h = tb->tb_id & (FIB_TABLE_HASHSZ - 1);
2482 while ((tb_node = rcu_dereference(hlist_next_rcu(&tb->tb_hlist)))) {
2483 tb = hlist_entry(tb_node, struct fib_table, tb_hlist);
2484 n = fib_trie_get_first(iter, (struct trie *) tb->tb_data);
2489 /* new hash chain */
2490 while (++h < FIB_TABLE_HASHSZ) {
2491 struct hlist_head *head = &net->ipv4.fib_table_hash[h];
2492 hlist_for_each_entry_rcu(tb, head, tb_hlist) {
2493 n = fib_trie_get_first(iter, (struct trie *) tb->tb_data);
2505 static void fib_trie_seq_stop(struct seq_file *seq, void *v)
2511 static void seq_indent(struct seq_file *seq, int n)
2517 static inline const char *rtn_scope(char *buf, size_t len, enum rt_scope_t s)
2520 case RT_SCOPE_UNIVERSE: return "universe";
2521 case RT_SCOPE_SITE: return "site";
2522 case RT_SCOPE_LINK: return "link";
2523 case RT_SCOPE_HOST: return "host";
2524 case RT_SCOPE_NOWHERE: return "nowhere";
2526 snprintf(buf, len, "scope=%d", s);
2531 static const char *const rtn_type_names[__RTN_MAX] = {
2532 [RTN_UNSPEC] = "UNSPEC",
2533 [RTN_UNICAST] = "UNICAST",
2534 [RTN_LOCAL] = "LOCAL",
2535 [RTN_BROADCAST] = "BROADCAST",
2536 [RTN_ANYCAST] = "ANYCAST",
2537 [RTN_MULTICAST] = "MULTICAST",
2538 [RTN_BLACKHOLE] = "BLACKHOLE",
2539 [RTN_UNREACHABLE] = "UNREACHABLE",
2540 [RTN_PROHIBIT] = "PROHIBIT",
2541 [RTN_THROW] = "THROW",
2543 [RTN_XRESOLVE] = "XRESOLVE",
2546 static inline const char *rtn_type(char *buf, size_t len, unsigned int t)
2548 if (t < __RTN_MAX && rtn_type_names[t])
2549 return rtn_type_names[t];
2550 snprintf(buf, len, "type %u", t);
2554 /* Pretty print the trie */
2555 static int fib_trie_seq_show(struct seq_file *seq, void *v)
2557 const struct fib_trie_iter *iter = seq->private;
2558 struct key_vector *n = v;
2560 if (IS_TRIE(node_parent_rcu(n)))
2561 fib_table_print(seq, iter->tb);
2564 __be32 prf = htonl(n->key);
2566 seq_indent(seq, iter->depth-1);
2567 seq_printf(seq, " +-- %pI4/%zu %u %u %u\n",
2568 &prf, KEYLENGTH - n->pos - n->bits, n->bits,
2569 tn_info(n)->full_children,
2570 tn_info(n)->empty_children);
2572 __be32 val = htonl(n->key);
2573 struct fib_alias *fa;
2575 seq_indent(seq, iter->depth);
2576 seq_printf(seq, " |-- %pI4\n", &val);
2578 hlist_for_each_entry_rcu(fa, &n->leaf, fa_list) {
2579 char buf1[32], buf2[32];
2581 seq_indent(seq, iter->depth + 1);
2582 seq_printf(seq, " /%zu %s %s",
2583 KEYLENGTH - fa->fa_slen,
2584 rtn_scope(buf1, sizeof(buf1),
2585 fa->fa_info->fib_scope),
2586 rtn_type(buf2, sizeof(buf2),
2589 seq_printf(seq, " tos=%d", fa->fa_tos);
2590 seq_putc(seq, '\n');
2597 static const struct seq_operations fib_trie_seq_ops = {
2598 .start = fib_trie_seq_start,
2599 .next = fib_trie_seq_next,
2600 .stop = fib_trie_seq_stop,
2601 .show = fib_trie_seq_show,
2604 static int fib_trie_seq_open(struct inode *inode, struct file *file)
2606 return seq_open_net(inode, file, &fib_trie_seq_ops,
2607 sizeof(struct fib_trie_iter));
2610 static const struct file_operations fib_trie_fops = {
2611 .owner = THIS_MODULE,
2612 .open = fib_trie_seq_open,
2614 .llseek = seq_lseek,
2615 .release = seq_release_net,
2618 struct fib_route_iter {
2619 struct seq_net_private p;
2620 struct fib_table *main_tb;
2621 struct key_vector *tnode;
2626 static struct key_vector *fib_route_get_idx(struct fib_route_iter *iter,
2629 struct key_vector *l, **tp = &iter->tnode;
2632 /* use cached location of previously found key */
2633 if (iter->pos > 0 && pos >= iter->pos) {
2642 while ((l = leaf_walk_rcu(tp, key)) && (pos-- > 0)) {
2647 /* handle unlikely case of a key wrap */
2653 iter->key = l->key; /* remember it */
2655 iter->pos = 0; /* forget it */
2660 static void *fib_route_seq_start(struct seq_file *seq, loff_t *pos)
2663 struct fib_route_iter *iter = seq->private;
2664 struct fib_table *tb;
2669 tb = fib_get_table(seq_file_net(seq), RT_TABLE_MAIN);
2674 t = (struct trie *)tb->tb_data;
2675 iter->tnode = t->kv;
2678 return fib_route_get_idx(iter, *pos);
2681 iter->key = KEY_MAX;
2683 return SEQ_START_TOKEN;
2686 static void *fib_route_seq_next(struct seq_file *seq, void *v, loff_t *pos)
2688 struct fib_route_iter *iter = seq->private;
2689 struct key_vector *l = NULL;
2690 t_key key = iter->key + 1;
2694 /* only allow key of 0 for start of sequence */
2695 if ((v == SEQ_START_TOKEN) || key)
2696 l = leaf_walk_rcu(&iter->tnode, key);
2708 static void fib_route_seq_stop(struct seq_file *seq, void *v)
2714 static unsigned int fib_flag_trans(int type, __be32 mask, const struct fib_info *fi)
2716 unsigned int flags = 0;
2718 if (type == RTN_UNREACHABLE || type == RTN_PROHIBIT)
2720 if (fi && fi->fib_nh->nh_gw)
2721 flags |= RTF_GATEWAY;
2722 if (mask == htonl(0xFFFFFFFF))
2729 * This outputs /proc/net/route.
2730 * The format of the file is not supposed to be changed
2731 * and needs to be same as fib_hash output to avoid breaking
2734 static int fib_route_seq_show(struct seq_file *seq, void *v)
2736 struct fib_route_iter *iter = seq->private;
2737 struct fib_table *tb = iter->main_tb;
2738 struct fib_alias *fa;
2739 struct key_vector *l = v;
2742 if (v == SEQ_START_TOKEN) {
2743 seq_printf(seq, "%-127s\n", "Iface\tDestination\tGateway "
2744 "\tFlags\tRefCnt\tUse\tMetric\tMask\t\tMTU"
2749 prefix = htonl(l->key);
2751 hlist_for_each_entry_rcu(fa, &l->leaf, fa_list) {
2752 const struct fib_info *fi = fa->fa_info;
2753 __be32 mask = inet_make_mask(KEYLENGTH - fa->fa_slen);
2754 unsigned int flags = fib_flag_trans(fa->fa_type, mask, fi);
2756 if ((fa->fa_type == RTN_BROADCAST) ||
2757 (fa->fa_type == RTN_MULTICAST))
2760 if (fa->tb_id != tb->tb_id)
2763 seq_setwidth(seq, 127);
2767 "%s\t%08X\t%08X\t%04X\t%d\t%u\t"
2768 "%d\t%08X\t%d\t%u\t%u",
2769 fi->fib_dev ? fi->fib_dev->name : "*",
2771 fi->fib_nh->nh_gw, flags, 0, 0,
2775 fi->fib_advmss + 40 : 0),
2780 "*\t%08X\t%08X\t%04X\t%d\t%u\t"
2781 "%d\t%08X\t%d\t%u\t%u",
2782 prefix, 0, flags, 0, 0, 0,
2791 static const struct seq_operations fib_route_seq_ops = {
2792 .start = fib_route_seq_start,
2793 .next = fib_route_seq_next,
2794 .stop = fib_route_seq_stop,
2795 .show = fib_route_seq_show,
2798 static int fib_route_seq_open(struct inode *inode, struct file *file)
2800 return seq_open_net(inode, file, &fib_route_seq_ops,
2801 sizeof(struct fib_route_iter));
2804 static const struct file_operations fib_route_fops = {
2805 .owner = THIS_MODULE,
2806 .open = fib_route_seq_open,
2808 .llseek = seq_lseek,
2809 .release = seq_release_net,
2812 int __net_init fib_proc_init(struct net *net)
2814 if (!proc_create("fib_trie", S_IRUGO, net->proc_net, &fib_trie_fops))
2817 if (!proc_create("fib_triestat", S_IRUGO, net->proc_net,
2818 &fib_triestat_fops))
2821 if (!proc_create("route", S_IRUGO, net->proc_net, &fib_route_fops))
2827 remove_proc_entry("fib_triestat", net->proc_net);
2829 remove_proc_entry("fib_trie", net->proc_net);
2834 void __net_exit fib_proc_exit(struct net *net)
2836 remove_proc_entry("fib_trie", net->proc_net);
2837 remove_proc_entry("fib_triestat", net->proc_net);
2838 remove_proc_entry("route", net->proc_net);
2841 #endif /* CONFIG_PROC_FS */