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authorRobert Olsson <Robert.Olsson@data.slu.se>2005-06-21 12:43:18 -0700
committerDavid S. Miller <davem@davemloft.net>2005-06-21 12:43:18 -0700
commit19baf839ff4a8daa1f2a7400897094fc18e4f5e9 (patch)
tree719e1b64a4fedc4fc028874b5562553c7a524473 /net
parent18b504e25fd617bee8830d2cdcaff7fb7b5931bb (diff)
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[IPV4]: Add LC-Trie FIB lookup algorithm.
Signed-off-by: Robert Olsson <Robert.Olsson@data.slu.se> Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'net')
-rw-r--r--net/ipv4/Kconfig26
-rw-r--r--net/ipv4/Makefile4
-rw-r--r--net/ipv4/af_inet.c12
-rw-r--r--net/ipv4/fib_trie.c2454
4 files changed, 2495 insertions, 1 deletions
diff --git a/net/ipv4/Kconfig b/net/ipv4/Kconfig
index 6d3e8b1bd1f..05107e0dc14 100644
--- a/net/ipv4/Kconfig
+++ b/net/ipv4/Kconfig
@@ -1,6 +1,32 @@
#
# IP configuration
#
+choice
+ prompt "Choose IP: FIB lookup""
+ depends on INET
+ default IP_FIB_HASH
+
+config IP_FIB_HASH
+ bool "FIB_HASH"
+ ---help---
+ Current FIB is very proven and good enough for most users.
+
+config IP_FIB_TRIE
+ bool "FIB_TRIE"
+ ---help---
+ Use new experimental LC-trie as FIB lookup algoritm.
+ This improves lookup performance
+
+ LC-trie is described in:
+
+ IP-address lookup using LC-tries. Stefan Nilsson and Gunnar Karlsson
+ IEEE Journal on Selected Areas in Communications, 17(6):1083-1092, June 1999
+ An experimental study of compression methods for dynamic tries
+ Stefan Nilsson and Matti Tikkanen. Algorithmica, 33(1):19-33, 2002.
+ http://www.nada.kth.se/~snilsson/public/papers/dyntrie2/
+
+endchoice
+
config IP_MULTICAST
bool "IP: multicasting"
depends on INET
diff --git a/net/ipv4/Makefile b/net/ipv4/Makefile
index 8b379627ebb..65d57d8e1ad 100644
--- a/net/ipv4/Makefile
+++ b/net/ipv4/Makefile
@@ -7,8 +7,10 @@ obj-y := utils.o route.o inetpeer.o protocol.o \
ip_output.o ip_sockglue.o \
tcp.o tcp_input.o tcp_output.o tcp_timer.o tcp_ipv4.o tcp_minisocks.o \
datagram.o raw.o udp.o arp.o icmp.o devinet.o af_inet.o igmp.o \
- sysctl_net_ipv4.o fib_frontend.o fib_semantics.o fib_hash.o
+ sysctl_net_ipv4.o fib_frontend.o fib_semantics.o
+obj-$(CONFIG_IP_FIB_HASH) += fib_hash.o
+obj-$(CONFIG_IP_FIB_TRIE) += fib_trie.o
obj-$(CONFIG_PROC_FS) += proc.o
obj-$(CONFIG_IP_MULTIPLE_TABLES) += fib_rules.o
obj-$(CONFIG_IP_MROUTE) += ipmr.o
diff --git a/net/ipv4/af_inet.c b/net/ipv4/af_inet.c
index 03942f13394..658e7977924 100644
--- a/net/ipv4/af_inet.c
+++ b/net/ipv4/af_inet.c
@@ -1119,6 +1119,10 @@ module_init(inet_init);
#ifdef CONFIG_PROC_FS
extern int fib_proc_init(void);
extern void fib_proc_exit(void);
+#ifdef CONFIG_IP_FIB_TRIE
+extern int fib_stat_proc_init(void);
+extern void fib_stat_proc_exit(void);
+#endif
extern int ip_misc_proc_init(void);
extern int raw_proc_init(void);
extern void raw_proc_exit(void);
@@ -1139,11 +1143,19 @@ static int __init ipv4_proc_init(void)
goto out_udp;
if (fib_proc_init())
goto out_fib;
+#ifdef CONFIG_IP_FIB_TRIE
+ if (fib_stat_proc_init())
+ goto out_fib_stat;
+ #endif
if (ip_misc_proc_init())
goto out_misc;
out:
return rc;
out_misc:
+#ifdef CONFIG_IP_FIB_TRIE
+ fib_stat_proc_exit();
+out_fib_stat:
+#endif
fib_proc_exit();
out_fib:
udp4_proc_exit();
diff --git a/net/ipv4/fib_trie.c b/net/ipv4/fib_trie.c
new file mode 100644
index 00000000000..c0ece94fc63
--- /dev/null
+++ b/net/ipv4/fib_trie.c
@@ -0,0 +1,2454 @@
+/*
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version
+ * 2 of the License, or (at your option) any later version.
+ *
+ * Robert Olsson <robert.olsson@its.uu.se> Uppsala Universitet
+ * & Swedish University of Agricultural Sciences.
+ *
+ * Jens Laas <jens.laas@data.slu.se> Swedish University of
+ * Agricultural Sciences.
+ *
+ * Hans Liss <hans.liss@its.uu.se> Uppsala Universitet
+ *
+ * This work is based on the LPC-trie which is originally descibed in:
+ *
+ * An experimental study of compression methods for dynamic tries
+ * Stefan Nilsson and Matti Tikkanen. Algorithmica, 33(1):19-33, 2002.
+ * http://www.nada.kth.se/~snilsson/public/papers/dyntrie2/
+ *
+ *
+ * IP-address lookup using LC-tries. Stefan Nilsson and Gunnar Karlsson
+ * IEEE Journal on Selected Areas in Communications, 17(6):1083-1092, June 1999
+ *
+ * Version: $Id: fib_trie.c,v 1.3 2005/06/08 14:20:01 robert Exp $
+ *
+ *
+ * Code from fib_hash has been reused which includes the following header:
+ *
+ *
+ * INET An implementation of the TCP/IP protocol suite for the LINUX
+ * operating system. INET is implemented using the BSD Socket
+ * interface as the means of communication with the user level.
+ *
+ * IPv4 FIB: lookup engine and maintenance routines.
+ *
+ *
+ * Authors: Alexey Kuznetsov, <kuznet@ms2.inr.ac.ru>
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version
+ * 2 of the License, or (at your option) any later version.
+ */
+
+#define VERSION "0.323"
+
+#include <linux/config.h>
+#include <asm/uaccess.h>
+#include <asm/system.h>
+#include <asm/bitops.h>
+#include <linux/types.h>
+#include <linux/kernel.h>
+#include <linux/sched.h>
+#include <linux/mm.h>
+#include <linux/string.h>
+#include <linux/socket.h>
+#include <linux/sockios.h>
+#include <linux/errno.h>
+#include <linux/in.h>
+#include <linux/inet.h>
+#include <linux/netdevice.h>
+#include <linux/if_arp.h>
+#include <linux/proc_fs.h>
+#include <linux/skbuff.h>
+#include <linux/netlink.h>
+#include <linux/init.h>
+#include <linux/list.h>
+#include <net/ip.h>
+#include <net/protocol.h>
+#include <net/route.h>
+#include <net/tcp.h>
+#include <net/sock.h>
+#include <net/ip_fib.h>
+#include "fib_lookup.h"
+
+#undef CONFIG_IP_FIB_TRIE_STATS
+#define MAX_CHILDS 16384
+
+#define EXTRACT(p, n, str) ((str)<<(p)>>(32-(n)))
+#define KEYLENGTH (8*sizeof(t_key))
+#define MASK_PFX(k, l) (((l)==0)?0:(k >> (KEYLENGTH-l)) << (KEYLENGTH-l))
+#define TKEY_GET_MASK(offset, bits) (((bits)==0)?0:((t_key)(-1) << (KEYLENGTH - bits) >> offset))
+
+static DEFINE_RWLOCK(fib_lock);
+
+typedef unsigned int t_key;
+
+#define T_TNODE 0
+#define T_LEAF 1
+#define NODE_TYPE_MASK 0x1UL
+#define NODE_PARENT(_node) \
+((struct tnode *)((_node)->_parent & ~NODE_TYPE_MASK))
+#define NODE_SET_PARENT(_node, _ptr) \
+((_node)->_parent = (((unsigned long)(_ptr)) | \
+ ((_node)->_parent & NODE_TYPE_MASK)))
+#define NODE_INIT_PARENT(_node, _type) \
+((_node)->_parent = (_type))
+#define NODE_TYPE(_node) \
+((_node)->_parent & NODE_TYPE_MASK)
+
+#define IS_TNODE(n) (!(n->_parent & T_LEAF))
+#define IS_LEAF(n) (n->_parent & T_LEAF)
+
+struct node {
+ t_key key;
+ unsigned long _parent;
+};
+
+struct leaf {
+ t_key key;
+ unsigned long _parent;
+ struct hlist_head list;
+};
+
+struct leaf_info {
+ struct hlist_node hlist;
+ int plen;
+ struct list_head falh;
+};
+
+struct tnode {
+ t_key key;
+ unsigned long _parent;
+ unsigned short pos:5; /* 2log(KEYLENGTH) bits needed */
+ unsigned short bits:5; /* 2log(KEYLENGTH) bits needed */
+ unsigned short full_children; /* KEYLENGTH bits needed */
+ unsigned short empty_children; /* KEYLENGTH bits needed */
+ struct node *child[0];
+};
+
+#ifdef CONFIG_IP_FIB_TRIE_STATS
+struct trie_use_stats {
+ unsigned int gets;
+ unsigned int backtrack;
+ unsigned int semantic_match_passed;
+ unsigned int semantic_match_miss;
+ unsigned int null_node_hit;
+};
+#endif
+
+struct trie_stat {
+ unsigned int totdepth;
+ unsigned int maxdepth;
+ unsigned int tnodes;
+ unsigned int leaves;
+ unsigned int nullpointers;
+ unsigned int nodesizes[MAX_CHILDS];
+};
+
+struct trie {
+ struct node *trie;
+#ifdef CONFIG_IP_FIB_TRIE_STATS
+ struct trie_use_stats stats;
+#endif
+ int size;
+ unsigned int revision;
+};
+
+static int trie_debug = 0;
+
+static int tnode_full(struct tnode *tn, struct node *n);
+static void put_child(struct trie *t, struct tnode *tn, int i, struct node *n);
+static void tnode_put_child_reorg(struct tnode *tn, int i, struct node *n, int wasfull);
+static int tnode_child_length(struct tnode *tn);
+static struct node *resize(struct trie *t, struct tnode *tn);
+static struct tnode *inflate(struct trie *t, struct tnode *tn);
+static struct tnode *halve(struct trie *t, struct tnode *tn);
+static void tnode_free(struct tnode *tn);
+static void trie_dump_seq(struct seq_file *seq, struct trie *t);
+extern struct fib_alias *fib_find_alias(struct list_head *fah, u8 tos, u32 prio);
+extern int fib_detect_death(struct fib_info *fi, int order,
+ struct fib_info **last_resort, int *last_idx, int *dflt);
+
+extern void rtmsg_fib(int event, u32 key, struct fib_alias *fa, int z, int tb_id,
+ struct nlmsghdr *n, struct netlink_skb_parms *req);
+
+static kmem_cache_t *fn_alias_kmem;
+static struct trie *trie_local = NULL, *trie_main = NULL;
+
+static void trie_bug(char *err)
+{
+ printk("Trie Bug: %s\n", err);
+ BUG();
+}
+
+static inline struct node *tnode_get_child(struct tnode *tn, int i)
+{
+ if (i >= 1<<tn->bits)
+ trie_bug("tnode_get_child");
+
+ return tn->child[i];
+}
+
+static inline int tnode_child_length(struct tnode *tn)
+{
+ return 1<<tn->bits;
+}
+
+/*
+ _________________________________________________________________
+ | i | i | i | i | i | i | i | N | N | N | S | S | S | S | S | C |
+ ----------------------------------------------------------------
+ 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15
+
+ _________________________________________________________________
+ | C | C | C | u | u | u | u | u | u | u | u | u | u | u | u | u |
+ -----------------------------------------------------------------
+ 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31
+
+ tp->pos = 7
+ tp->bits = 3
+ n->pos = 15
+ n->bits=4
+ KEYLENGTH=32
+*/
+
+static inline t_key tkey_extract_bits(t_key a, int offset, int bits)
+{
+ if (offset < KEYLENGTH)
+ return ((t_key)(a << offset)) >> (KEYLENGTH - bits);
+ else
+ return 0;
+}
+
+static inline int tkey_equals(t_key a, t_key b)
+{
+ return a == b;
+}
+
+static inline int tkey_sub_equals(t_key a, int offset, int bits, t_key b)
+{
+ if (bits == 0 || offset >= KEYLENGTH)
+ return 1;
+ bits = bits > KEYLENGTH ? KEYLENGTH : bits;
+ return ((a ^ b) << offset) >> (KEYLENGTH - bits) == 0;
+}
+
+static inline int tkey_mismatch(t_key a, int offset, t_key b)
+{
+ t_key diff = a ^ b;
+ int i = offset;
+
+ if(!diff)
+ return 0;
+ while((diff << i) >> (KEYLENGTH-1) == 0)
+ i++;
+ return i;
+}
+
+/* Candiate for fib_semantics */
+
+static void fn_free_alias(struct fib_alias *fa)
+{
+ fib_release_info(fa->fa_info);
+ kmem_cache_free(fn_alias_kmem, fa);
+}
+
+/*
+ To understand this stuff, an understanding of keys and all their bits is
+ necessary. Every node in the trie has a key associated with it, but not
+ all of the bits in that key are significant.
+
+ Consider a node 'n' and its parent 'tp'.
+
+ If n is a leaf, every bit in its key is significant. Its presence is
+ necessitaded by path compression, since during a tree traversal (when
+ searching for a leaf - unless we are doing an insertion) we will completely
+ ignore all skipped bits we encounter. Thus we need to verify, at the end of
+ a potentially successful search, that we have indeed been walking the
+ correct key path.
+
+ Note that we can never "miss" the correct key in the tree if present by
+ following the wrong path. Path compression ensures that segments of the key
+ that are the same for all keys with a given prefix are skipped, but the
+ skipped part *is* identical for each node in the subtrie below the skipped
+ bit! trie_insert() in this implementation takes care of that - note the
+ call to tkey_sub_equals() in trie_insert().
+
+ if n is an internal node - a 'tnode' here, the various parts of its key
+ have many different meanings.
+
+ Example:
+ _________________________________________________________________
+ | i | i | i | i | i | i | i | N | N | N | S | S | S | S | S | C |
+ -----------------------------------------------------------------
+ 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15
+
+ _________________________________________________________________
+ | C | C | C | u | u | u | u | u | u | u | u | u | u | u | u | u |
+ -----------------------------------------------------------------
+ 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31
+
+ tp->pos = 7
+ tp->bits = 3
+ n->pos = 15
+ n->bits=4
+
+ First, let's just ignore the bits that come before the parent tp, that is
+ the bits from 0 to (tp->pos-1). They are *known* but at this point we do
+ not use them for anything.
+
+ The bits from (tp->pos) to (tp->pos + tp->bits - 1) - "N", above - are the
+ index into the parent's child array. That is, they will be used to find
+ 'n' among tp's children.
+
+ The bits from (tp->pos + tp->bits) to (n->pos - 1) - "S" - are skipped bits
+ for the node n.
+
+ All the bits we have seen so far are significant to the node n. The rest
+ of the bits are really not needed or indeed known in n->key.
+
+ The bits from (n->pos) to (n->pos + n->bits - 1) - "C" - are the index into
+ n's child array, and will of course be different for each child.
+
+ The rest of the bits, from (n->pos + n->bits) onward, are completely unknown
+ at this point.
+
+*/
+
+static void check_tnode(struct tnode *tn)
+{
+ if(tn && tn->pos+tn->bits > 32) {
+ printk("TNODE ERROR tn=%p, pos=%d, bits=%d\n", tn, tn->pos, tn->bits);
+ }
+}
+
+static int halve_threshold = 25;
+static int inflate_threshold = 50;
+
+static struct leaf *leaf_new(void)
+{
+ struct leaf *l = kmalloc(sizeof(struct leaf), GFP_KERNEL);
+ if(l) {
+ NODE_INIT_PARENT(l, T_LEAF);
+ INIT_HLIST_HEAD(&l->list);
+ }
+ return l;
+}
+
+static struct leaf_info *leaf_info_new(int plen)
+{
+ struct leaf_info *li = kmalloc(sizeof(struct leaf_info), GFP_KERNEL);
+ li->plen = plen;
+ INIT_LIST_HEAD(&li->falh);
+ return li;
+}
+
+static inline void free_leaf(struct leaf *l)
+{
+ kfree(l);
+}
+
+static inline void free_leaf_info(struct leaf_info *li)
+{
+ kfree(li);
+}
+
+static struct tnode* tnode_new(t_key key, int pos, int bits)
+{
+ int nchildren = 1<<bits;
+ int sz = sizeof(struct tnode) + nchildren * sizeof(struct node *);
+ struct tnode *tn = kmalloc(sz, GFP_KERNEL);
+
+ if(tn) {
+ memset(tn, 0, sz);
+ NODE_INIT_PARENT(tn, T_TNODE);
+ tn->pos = pos;
+ tn->bits = bits;
+ tn->key = key;
+ tn->full_children = 0;
+ tn->empty_children = 1<<bits;
+ }
+ if(trie_debug > 0)
+ printk("AT %p s=%u %u\n", tn, (unsigned int) sizeof(struct tnode),
+ (unsigned int) (sizeof(struct node) * 1<<bits));
+ return tn;
+}
+
+static void tnode_free(struct tnode *tn)
+{
+ if(!tn) {
+ trie_bug("tnode_free\n");
+ }
+ if(IS_LEAF(tn)) {
+ free_leaf((struct leaf *)tn);
+ if(trie_debug > 0 )
+ printk("FL %p \n", tn);
+ }
+ else if(IS_TNODE(tn)) {
+ kfree(tn);
+ if(trie_debug > 0 )
+ printk("FT %p \n", tn);
+ }
+ else {
+ trie_bug("tnode_free\n");
+ }
+}
+
+/*
+ * Check whether a tnode 'n' is "full", i.e. it is an internal node
+ * and no bits are skipped. See discussion in dyntree paper p. 6
+ */
+
+static inline int tnode_full(struct tnode *tn, struct node *n)
+{
+ if(n == NULL || IS_LEAF(n))
+ return 0;
+
+ return ((struct tnode *) n)->pos == tn->pos + tn->bits;
+}
+
+static inline void put_child(struct trie *t, struct tnode *tn, int i, struct node *n)
+{
+ tnode_put_child_reorg(tn, i, n, -1);
+}
+
+ /*
+ * Add a child at position i overwriting the old value.
+ * Update the value of full_children and empty_children.
+ */
+
+static void tnode_put_child_reorg(struct tnode *tn, int i, struct node *n, int wasfull)
+{
+ struct node *chi;
+ int isfull;
+
+ if(i >= 1<<tn->bits) {
+ printk("bits=%d, i=%d\n", tn->bits, i);
+ trie_bug("tnode_put_child_reorg bits");
+ }
+ write_lock_bh(&fib_lock);
+ chi = tn->child[i];
+
+ /* update emptyChildren */
+ if (n == NULL && chi != NULL)
+ tn->empty_children++;
+ else if (n != NULL && chi == NULL)
+ tn->empty_children--;
+
+ /* update fullChildren */
+ if (wasfull == -1)
+ wasfull = tnode_full(tn, chi);
+
+ isfull = tnode_full(tn, n);
+ if (wasfull && !isfull)
+ tn->full_children--;
+
+ else if (!wasfull && isfull)
+ tn->full_children++;
+ if(n)
+ NODE_SET_PARENT(n, tn);
+
+ tn->child[i] = n;
+ write_unlock_bh(&fib_lock);
+}
+
+static struct node *resize(struct trie *t, struct tnode *tn)
+{
+ int i;
+
+ if (!tn)
+ return NULL;
+
+ if(trie_debug)
+ printk("In tnode_resize %p inflate_threshold=%d threshold=%d\n",
+ tn, inflate_threshold, halve_threshold);
+
+ /* No children */
+ if (tn->empty_children == tnode_child_length(tn)) {
+ tnode_free(tn);
+ return NULL;
+ }
+ /* One child */
+ if (tn->empty_children == tnode_child_length(tn) - 1)
+ for (i = 0; i < tnode_child_length(tn); i++) {
+
+ write_lock_bh(&fib_lock);
+ if (tn->child[i] != NULL) {
+
+ /* compress one level */
+ struct node *n = tn->child[i];
+ if(n)
+ NODE_INIT_PARENT(n, NODE_TYPE(n));
+
+ write_unlock_bh(&fib_lock);
+ tnode_free(tn);
+ return n;
+ }
+ write_unlock_bh(&fib_lock);
+ }
+ /*
+ * Double as long as the resulting node has a number of
+ * nonempty nodes that are above the threshold.
+ */
+
+ /*
+ * From "Implementing a dynamic compressed trie" by Stefan Nilsson of
+ * the Helsinki University of Technology and Matti Tikkanen of Nokia
+ * Telecommunications, page 6:
+ * "A node is doubled if the ratio of non-empty children to all
+ * children in the *doubled* node is at least 'high'."
+ *
+ * 'high' in this instance is the variable 'inflate_threshold'. It
+ * is expressed as a percentage, so we multiply it with
+ * tnode_child_length() and instead of multiplying by 2 (since the
+ * child array will be doubled by inflate()) and multiplying
+ * the left-hand side by 100 (to handle the percentage thing) we
+ * multiply the left-hand side by 50.
+ *
+ * The left-hand side may look a bit weird: tnode_child_length(tn)
+ * - tn->empty_children is of course the number of non-null children
+ * in the current node. tn->full_children is the number of "full"
+ * children, that is non-null tnodes with a skip value of 0.
+ * All of those will be doubled in the resulting inflated tnode, so
+ * we just count them one extra time here.
+ *
+ * A clearer way to write this would be:
+ *
+ * to_be_doubled = tn->full_children;
+ * not_to_be_doubled = tnode_child_length(tn) - tn->empty_children -
+ * tn->full_children;
+ *
+ * new_child_length = tnode_child_length(tn) * 2;
+ *
+ * new_fill_factor = 100 * (not_to_be_doubled + 2*to_be_doubled) /
+ * new_child_length;
+ * if (new_fill_factor >= inflate_threshold)
+ *
+ * ...and so on, tho it would mess up the while() loop.
+ *
+ * anyway,
+ * 100 * (not_to_be_doubled + 2*to_be_doubled) / new_child_length >=
+ * inflate_threshold
+ *
+ * avoid a division:
+ * 100 * (not_to_be_doubled + 2*to_be_doubled) >=
+ * inflate_threshold * new_child_length
+ *
+ * expand not_to_be_doubled and to_be_doubled, and shorten:
+ * 100 * (tnode_child_length(tn) - tn->empty_children +
+ * tn->full_children ) >= inflate_threshold * new_child_length
+ *
+ * expand new_child_length:
+ * 100 * (tnode_child_length(tn) - tn->empty_children +
+ * tn->full_children ) >=
+ * inflate_threshold * tnode_child_length(tn) * 2
+ *
+ * shorten again:
+ * 50 * (tn->full_children + tnode_child_length(tn) -
+ * tn->empty_children ) >= inflate_threshold *
+ * tnode_child_length(tn)
+ *
+ */
+
+ check_tnode(tn);
+
+ while ((tn->full_children > 0 &&
+ 50 * (tn->full_children + tnode_child_length(tn) - tn->empty_children) >=
+ inflate_threshold * tnode_child_length(tn))) {
+
+ tn = inflate(t, tn);
+ }
+
+ check_tnode(tn);
+
+ /*
+ * Halve as long as the number of empty children in this
+ * node is above threshold.
+ */
+ while (tn->bits > 1 &&
+ 100 * (tnode_child_length(tn) - tn->empty_children) <
+ halve_threshold * tnode_child_length(tn))
+
+ tn = halve(t, tn);
+
+ /* Only one child remains */
+
+ if (tn->empty_children == tnode_child_length(tn) - 1)
+ for (i = 0; i < tnode_child_length(tn); i++) {
+
+ write_lock_bh(&fib_lock);
+ if (tn->child[i] != NULL) {
+ /* compress one level */
+ struct node *n = tn->child[i];
+
+ if(n)
+ NODE_INIT_PARENT(n, NODE_TYPE(n));
+
+ write_unlock_bh(&fib_lock);
+ tnode_free(tn);
+ return n;
+ }
+ write_unlock_bh(&fib_lock);
+ }
+
+ return (struct node *) tn;
+}
+
+static struct tnode *inflate(struct trie *t, struct tnode *tn)
+{
+ struct tnode *inode;
+ struct tnode *oldtnode = tn;
+ int olen = tnode_child_length(tn);
+ int i;
+
+ if(trie_debug)
+ printk("In inflate\n");
+
+ tn = tnode_new(oldtnode->key, oldtnode->pos, oldtnode->bits + 1);
+
+ if (!tn)
+ trie_bug("tnode_new failed");
+
+ for(i = 0; i < olen; i++) {
+ struct node *node = tnode_get_child(oldtnode, i);
+
+ /* An empty child */
+ if (node == NULL)
+ continue;
+
+ /* A leaf or an internal node with skipped bits */
+
+ if(IS_LEAF(node) || ((struct tnode *) node)->pos >
+ tn->pos + tn->bits - 1) {
+ if(tkey_extract_bits(node->key, tn->pos + tn->bits - 1,
+ 1) == 0)
+ put_child(t, tn, 2*i, node);
+ else
+ put_child(t, tn, 2*i+1, node);
+ continue;
+ }
+
+ /* An internal node with two children */
+ inode = (struct tnode *) node;
+
+ if (inode->bits == 1) {
+ put_child(t, tn, 2*i, inode->child[0]);
+ put_child(t, tn, 2*i+1, inode->child[1]);
+
+ tnode_free(inode);
+ }
+
+ /* An internal node with more than two children */
+ else {
+ struct tnode *left, *right;
+ int size, j;
+
+ /* We will replace this node 'inode' with two new
+ * ones, 'left' and 'right', each with half of the
+ * original children. The two new nodes will have
+ * a position one bit further down the key and this
+ * means that the "significant" part of their keys
+ * (see the discussion near the top of this file)
+ * will differ by one bit, which will be "0" in
+ * left's key and "1" in right's key. Since we are
+ * moving the key position by one step, the bit that
+ * we are moving away from - the bit at position
+ * (inode->pos) - is the one that will differ between
+ * left and right. So... we synthesize that bit in the
+ * two new keys.
+ * The mask 'm' below will be a single "one" bit at
+ * the position (inode->pos)
+ */
+
+ t_key m = TKEY_GET_MASK(inode->pos, 1);
+
+ /* Use the old key, but set the new significant
+ * bit to zero.
+ */
+ left = tnode_new(inode->key&(~m), inode->pos + 1,
+ inode->bits - 1);
+
+ if(!left)
+ trie_bug("tnode_new failed");
+
+
+ /* Use the old key, but set the new significant
+ * bit to one.
+ */
+ right = tnode_new(inode->key|m, inode->pos + 1,
+ inode->bits - 1);
+
+ if(!right)
+ trie_bug("tnode_new failed");
+
+ size = tnode_child_length(left);
+ for(j = 0; j < size; j++) {
+ put_child(t, left, j, inode->child[j]);
+ put_child(t, right, j, inode->child[j + size]);
+ }
+ put_child(t, tn, 2*i, resize(t, left));
+ put_child(t, tn, 2*i+1, resize(t, right));
+
+ tnode_free(inode);
+ }
+ }
+ tnode_free(oldtnode);
+ return tn;
+}
+
+static struct tnode *halve(struct trie *t, struct tnode *tn)
+{
+ struct tnode *oldtnode = tn;
+ struct node *left, *right;
+ int i;
+ int olen = tnode_child_length(tn);
+
+ if(trie_debug) printk("In halve\n");
+
+ tn=tnode_new(oldtnode->key, oldtnode->pos, oldtnode->bits - 1);
+
+ if(!tn)
+ trie_bug("tnode_new failed");
+
+ for(i = 0; i < olen; i += 2) {
+ left = tnode_get_child(oldtnode, i);
+ right = tnode_get_child(oldtnode, i+1);
+
+ /* At least one of the children is empty */
+ if (left == NULL) {
+ if (right == NULL) /* Both are empty */
+ continue;
+ put_child(t, tn, i/2, right);
+ } else if (right == NULL)
+ put_child(t, tn, i/2, left);
+
+ /* Two nonempty children */
+ else {
+ struct tnode *newBinNode =
+ tnode_new(left->key, tn->pos + tn->bits, 1);
+
+ if(!newBinNode)
+ trie_bug("tnode_new failed");
+
+ put_child(t, newBinNode, 0, left);
+ put_child(t, newBinNode, 1, right);
+ put_child(t, tn, i/2, resize(t, newBinNode));
+ }
+ }
+ tnode_free(oldtnode);
+ return tn;
+}
+
+static void *trie_init(struct trie *t)
+{
+ if(t) {
+ t->size = 0;
+ t->trie = NULL;
+ t->revision = 0;
+#ifdef CONFIG_IP_FIB_TRIE_STATS
+ memset(&t->stats, 0, sizeof(struct trie_use_stats));
+#endif
+ }
+ return t;
+}
+
+static struct leaf_info *find_leaf_info(struct hlist_head *head, int plen)
+{
+ struct hlist_node *node;
+ struct leaf_info *li;
+
+ hlist_for_each_entry(li, node, head, hlist) {
+
+ if ( li->plen == plen )
+ return li;
+ }
+ return NULL;
+}
+
+static inline struct list_head * get_fa_head(struct leaf *l, int plen)
+{
+ struct list_head *fa_head=NULL;
+ struct leaf_info *li = find_leaf_info(&l->list, plen);
+
+ if(li)
+ fa_head = &li->falh;
+
+ return fa_head;
+}
+
+static void insert_leaf_info(struct hlist_head *head, struct leaf_info *new)
+{
+ struct leaf_info *li=NULL, *last=NULL;
+ struct hlist_node *node, *tmp;
+
+ write_lock_bh(&fib_lock);
+
+ if(hlist_empty(head))
+ hlist_add_head(&new->hlist, head);
+ else {
+ hlist_for_each_entry_safe(li, node, tmp, head, hlist) {
+
+ if (new->plen > li->plen)
+ break;
+
+ last = li;
+ }
+ if(last)
+ hlist_add_after(&last->hlist, &new->hlist);
+ else
+ hlist_add_before(&new->hlist, &li->hlist);
+ }
+ write_unlock_bh(&fib_lock);
+}
+
+static struct leaf *
+fib_find_node(struct trie *t, u32 key)
+{
+ int pos;
+ struct tnode *tn;
+ struct node *n;
+
+ pos = 0;
+ n=t->trie;
+
+ while (n != NULL && NODE_TYPE(n) == T_TNODE) {
+ tn = (struct tnode *) n;
+
+ check_tnode(tn);
+
+ if(tkey_sub_equals(tn->key, pos, tn->pos-pos, key)) {
+ pos=tn->pos + tn->bits;
+ n = tnode_get_child(tn, tkey_extract_bits(key, tn->pos, tn->bits));
+ }
+ else
+ break;
+ }
+ /* Case we have found a leaf. Compare prefixes */
+
+ if (n != NULL && IS_LEAF(n) && tkey_equals(key, n->key)) {
+ struct leaf *l = (struct leaf *) n;
+ return l;
+ }
+ return NULL;
+}
+
+static struct node *trie_rebalance(struct trie *t, struct tnode *tn)
+{
+ int i = 0;
+ int wasfull;
+ t_key cindex, key;
+ struct tnode *tp = NULL;
+
+ if(!tn)
+ BUG();
+
+ key = tn->key;
+ i = 0;
+
+ while (tn != NULL && NODE_PARENT(tn) != NULL) {
+
+ if( i > 10 ) {
+ printk("Rebalance tn=%p \n", tn);
+ if(tn) printk("tn->parent=%p \n", NODE_PARENT(tn));
+
+ printk("Rebalance tp=%p \n", tp);
+ if(tp) printk("tp->parent=%p \n", NODE_PARENT(tp));
+ }
+
+ if( i > 12 ) BUG();
+ i++;
+
+ tp = NODE_PARENT(tn);
+ cindex = tkey_extract_bits(key, tp->pos, tp->bits);
+ wasfull = tnode_full(tp, tnode_get_child(tp, cindex));
+ tn = (struct tnode *) resize (t, (struct tnode *)tn);
+ tnode_put_child_reorg((struct tnode *)tp, cindex,(struct node*)tn, wasfull);
+
+ if(!NODE_PARENT(tn))
+ break;
+
+ tn = NODE_PARENT(tn);
+ }
+ /* Handle last (top) tnode */
+ if (IS_TNODE(tn))
+ tn = (struct tnode*) resize(t, (struct tnode *)tn);
+
+ return (struct node*) tn;
+}
+
+static struct list_head *
+fib_insert_node(struct trie *t, u32 key, int plen)
+{
+ int pos, newpos;
+ struct tnode *tp = NULL, *tn = NULL;
+ struct node *n;
+ struct leaf *l;
+ int missbit;
+ struct list_head *fa_head=NULL;
+ struct leaf_info *li;
+ t_key cindex;
+
+ pos = 0;
+ n=t->trie;
+
+ /* If we point to NULL, stop. Either the tree is empty and we should
+ * just put a new leaf in if, or we have reached an empty child slot,
+ * and we should just put our new leaf in that.
+ * If we point to a T_TNODE, check if it matches our key. Note that
+ * a T_TNODE might be skipping any number of bits - its 'pos' need
+ * not be the parent's 'pos'+'bits'!
+ *
+ * If it does match the current key, get pos/bits from it, extract
+ * the index from our key, push the T_TNODE and walk the tree.
+ *
+ * If it doesn't, we have to replace it with a new T_TNODE.
+ *
+ * If we point to a T_LEAF, it might or might not have the same key
+ * as we do. If it does, just change the value, update the T_LEAF's
+ * value, and return it.
+ * If it doesn't, we need to replace it with a T_TNODE.
+ */
+
+ while (n != NULL && NODE_TYPE(n) == T_TNODE) {
+ tn = (struct tnode *) n;
+
+ check_tnode(tn);
+
+ if(tkey_sub_equals(tn->key, pos, tn->pos-pos, key)) {
+ tp = tn;
+ pos=tn->pos + tn->bits;
+ n = tnode_get_child(tn, tkey_extract_bits(key, tn->pos, tn->bits));
+
+ if(n && NODE_PARENT(n) != tn) {
+ printk("BUG tn=%p, n->parent=%p\n", tn, NODE_PARENT(n));
+ BUG();
+ }
+ }
+ else
+ break;
+ }
+
+ /*
+ * n ----> NULL, LEAF or TNODE
+ *
+ * tp is n's (parent) ----> NULL or TNODE
+ */
+
+ if(tp && IS_LEAF(tp))
+ BUG();
+
+ t->revision++;
+
+ /* Case 1: n is a leaf. Compare prefixes */
+
+ if (n != NULL && IS_LEAF(n) && tkey_equals(key, n->key)) {
+ struct leaf *l = ( struct leaf *) n;
+
+ li = leaf_info_new(plen);
+
+ if(! li)
+ BUG();
+
+ fa_head = &li->falh;
+ insert_leaf_info(&l->list, li);
+ goto done;
+ }
+ t->size++;
+ l = leaf_new();
+
+ if(! l)
+ BUG();
+
+ l->key = key;
+ li = leaf_info_new(plen);
+
+ if(! li)
+ BUG();
+
+ fa_head = &li->falh;
+ insert_leaf_info(&l->list, li);
+
+ /* Case 2: n is NULL, and will just insert a new leaf */
+ if (t->trie && n == NULL) {
+
+ NODE_SET_PARENT(l, tp);
+
+ if (!tp)
+ BUG();
+
+ else {
+ cindex = tkey_extract_bits(key, tp->pos, tp->bits);
+ put_child(t, (struct tnode *)tp, cindex, (struct node *)l);
+ }
+ }
+ /* Case 3: n is a LEAF or a TNODE and the key doesn't match. */
+ else {
+ /*
+ * Add a new tnode here
+ * first tnode need some special handling
+ */
+
+ if (tp)
+ pos=tp->pos+tp->bits;
+ else
+ pos=0;
+ if(n) {
+ newpos = tkey_mismatch(key, pos, n->key);
+ tn = tnode_new(n->key, newpos, 1);
+ }
+ else {
+ newpos = 0;
+ tn = tnode_new(key, newpos, 1); /* First tnode */
+ }
+ if(!tn)
+ trie_bug("tnode_pfx_new failed");
+
+ NODE_SET_PARENT(tn, tp);
+
+ missbit=tkey_extract_bits(key, newpos, 1);
+ put_child(t, tn, missbit, (struct node *)l);
+ put_child(t, tn, 1-missbit, n);
+
+ if(tp) {
+ cindex = tkey_extract_bits(key, tp->pos, tp->bits);
+ put_child(t, (struct tnode *)tp, cindex, (struct node *)tn);
+ }
+ else {
+ t->trie = (struct node*) tn; /* First tnode */
+ tp = tn;
+ }
+ }
+ if(tp && tp->pos+tp->bits > 32) {
+ printk("ERROR tp=%p pos=%d, bits=%d, key=%0x plen=%d\n",
+ tp, tp->pos, tp->bits, key, plen);
+ }
+ /* Rebalance the trie */
+ t->trie = trie_rebalance(t, tp);
+done:;
+ return fa_head;
+}
+
+static int
+fn_trie_insert(struct fib_table *tb, struct rtmsg *r, struct kern_rta *rta,
+ struct nlmsghdr *nlhdr, struct netlink_skb_parms *req)
+{
+ struct trie *t = (struct trie *) tb->tb_data;
+ struct fib_alias *fa, *new_fa;
+ struct list_head *fa_head=NULL;
+ struct fib_info *fi;
+ int plen = r->rtm_dst_len;
+ int type = r->rtm_type;
+ u8 tos = r->rtm_tos;
+ u32 key, mask;
+ int err;
+ struct leaf *l;
+
+ if (plen > 32)
+ return -EINVAL;
+
+ key = 0;
+ if (rta->rta_dst)
+ memcpy(&key, rta->rta_dst, 4);
+
+ key = ntohl(key);
+
+ if(trie_debug)
+ printk("Insert table=%d %08x/%d\n", tb->tb_id, key, plen);
+
+ mask = ntohl( inet_make_mask(plen) );
+
+ if(key & ~mask)
+ return -EINVAL;
+
+ key = key & mask;
+
+ if ((fi = fib_create_info(r, rta, nlhdr, &err)) == NULL)
+ goto err;
+
+ l = fib_find_node(t, key);
+ fa = NULL;
+
+ if(l) {
+ fa_head = get_fa_head(l, plen);
+ fa = fib_find_alias(fa_head, tos, fi->fib_priority);
+ }
+
+ /* Now fa, if non-NULL, points to the first fib alias
+ * with the same keys [prefix,tos,priority], if such key already
+ * exists or to the node before which we will insert new one.
+ *
+ * If fa is NULL, we will need to allocate a new one and
+ * insert to the head of f.
+ *
+ * If f is NULL, no fib node matched the destination key
+ * and we need to allocate a new one of those as well.
+ */
+
+ if (fa &&
+ fa->fa_info->fib_priority == fi->fib_priority) {
+ struct fib_alias *fa_orig;
+
+ err = -EEXIST;
+ if (nlhdr->nlmsg_flags & NLM_F_EXCL)
+ goto out;
+
+ if (nlhdr->nlmsg_flags & NLM_F_REPLACE) {
+ struct fib_info *fi_drop;
+ u8 state;
+
+ write_lock_bh(&fib_lock);
+
+ fi_drop = fa->fa_info;
+ fa->fa_info = fi;
+ fa->fa_type = type;
+ fa->fa_scope = r->rtm_scope;
+ state = fa->fa_state;
+ fa->fa_state &= ~FA_S_ACCESSED;
+
+ write_unlock_bh(&fib_lock);
+
+ fib_release_info(fi_drop);
+ if (state & FA_S_ACCESSED)
+ rt_cache_flush(-1);
+
+ goto succeeded;
+ }
+ /* Error if we find a perfect match which
+ * uses the same scope, type, and nexthop
+ * information.
+ */
+ fa_orig = fa;
+ list_for_each_entry(fa, fa_orig->fa_list.prev, fa_list) {
+ if (fa->fa_tos != tos)
+ break;
+ if (fa->fa_info->fib_priority != fi->fib_priority)
+ break;
+ if (fa->fa_type == type &&
+ fa->fa_scope == r->rtm_scope &&
+ fa->fa_info == fi) {
+ goto out;
+ }
+ }
+ if (!(nlhdr->nlmsg_flags & NLM_F_APPEND))
+ fa = fa_orig;
+ }
+ err = -ENOENT;
+ if (!(nlhdr->nlmsg_flags&NLM_F_CREATE))
+ goto out;
+
+ err = -ENOBUFS;
+ new_fa = kmem_cache_alloc(fn_alias_kmem, SLAB_KERNEL);
+ if (new_fa == NULL)
+ goto out;
+
+ new_fa->fa_info = fi;
+ new_fa->fa_tos = tos;
+ new_fa->fa_type = type;
+ new_fa->fa_scope = r->rtm_scope;
+ new_fa->fa_state = 0;
+#if 0
+ new_fa->dst = NULL;
+#endif
+ /*
+ * Insert new entry to the list.
+ */
+
+ if(!fa_head)
+ fa_head = fib_insert_node(t, key, plen);
+
+ write_lock_bh(&fib_lock);
+
+ list_add_tail(&new_fa->fa_list,
+ (fa ? &fa->fa_list : fa_head));
+
+ write_unlock_bh(&fib_lock);
+
+ rt_cache_flush(-1);
+ rtmsg_fib(RTM_NEWROUTE, htonl(key), new_fa, plen, tb->tb_id, nlhdr, req);
+succeeded:
+ return 0;
+out:
+ fib_release_info(fi);
+err:;
+ return err;
+}
+
+static inline int check_leaf(struct trie *t, struct leaf *l, t_key key, int *plen, const struct flowi *flp,
+ struct fib_result *res, int *err)
+{
+ int i;
+ t_key mask;
+ struct leaf_info *li;
+ struct hlist_head *hhead = &l->list;
+ struct hlist_node *node;
+
+ hlist_for_each_entry(li, node, hhead, hlist) {
+
+ i = li->plen;
+ mask = ntohl(inet_make_mask(i));
+ if (l->key != (key & mask))
+ continue;
+
+ if (((*err) = fib_semantic_match(&li->falh, flp, res, l->key, mask, i)) == 0) {
+ *plen = i;
+#ifdef CONFIG_IP_FIB_TRIE_STATS
+ t->stats.semantic_match_passed++;
+#endif
+ return 1;
+ }
+#ifdef CONFIG_IP_FIB_TRIE_STATS
+ t->stats.semantic_match_miss++;
+#endif
+ }
+ return 0;
+}
+
+static int
+fn_trie_lookup(struct fib_table *tb, const struct flowi *flp, struct fib_result *res)
+{
+ struct trie *t = (struct trie *) tb->tb_data;
+ int plen, ret = 0;
+ struct node *n;
+ struct tnode *pn;
+ int pos, bits;
+ t_key key=ntohl(flp->fl4_dst);
+ int chopped_off;
+ t_key cindex = 0;
+ int current_prefix_length = KEYLENGTH;
+ n = t->trie;
+
+ read_lock(&fib_lock);
+ if(!n)
+ goto failed;
+
+#ifdef CONFIG_IP_FIB_TRIE_STATS
+ t->stats.gets++;
+#endif
+
+ /* Just a leaf? */
+ if (IS_LEAF(n)) {
+ if( check_leaf(t, (struct leaf *)n, key, &plen, flp, res, &ret) )
+ goto found;
+ goto failed;
+ }
+ pn = (struct tnode *) n;
+ chopped_off = 0;
+
+ while (pn) {
+
+ pos = pn->pos;
+ bits = pn->bits;
+
+ if(!chopped_off)
+ cindex = tkey_extract_bits(MASK_PFX(key, current_prefix_length), pos, bits);
+
+ n = tnode_get_child(pn, cindex);
+
+ if (n == NULL) {
+#ifdef CONFIG_IP_FIB_TRIE_STATS
+ t->stats.null_node_hit++;
+#endif
+ goto backtrace;
+ }
+
+ if (IS_TNODE(n)) {
+#define HL_OPTIMIZE
+#ifdef HL_OPTIMIZE
+ struct tnode *cn = (struct tnode *)n;
+ t_key node_prefix, key_prefix, pref_mismatch;
+ int mp;
+
+ /*
+ * It's a tnode, and we can do some extra checks here if we
+ * like, to avoid descending into a dead-end branch.
+ * This tnode is in the parent's child array at index
+ * key[p_pos..p_pos+p_bits] but potentially with some bits
+ * chopped off, so in reality the index may be just a
+ * subprefix, padded with zero at the end.
+ * We can also take a look at any skipped bits in this
+ * tnode - everything up to p_pos is supposed to be ok,
+ * and the non-chopped bits of the index (se previous
+ * paragraph) are also guaranteed ok, but the rest is
+ * considered unknown.
+ *
+ * The skipped bits are key[pos+bits..cn->pos].
+ */
+
+ /* If current_prefix_length < pos+bits, we are already doing
+ * actual prefix matching, which means everything from
+ * pos+(bits-chopped_off) onward must be zero along some
+ * branch of this subtree - otherwise there is *no* valid
+ * prefix present. Here we can only check the skipped
+ * bits. Remember, since we have already indexed into the
+ * parent's child array, we know that the bits we chopped of
+ * *are* zero.
+ */
+
+ /* NOTA BENE: CHECKING ONLY SKIPPED BITS FOR THE NEW NODE HERE */
+
+ if (current_prefix_length < pos+bits) {
+ if (tkey_extract_bits(cn->key, current_prefix_length,
+ cn->pos - current_prefix_length) != 0 ||
+ !(cn->child[0]))
+ goto backtrace;
+ }
+
+ /*
+ * If chopped_off=0, the index is fully validated and we
+ * only need to look at the skipped bits for this, the new,
+ * tnode. What we actually want to do is to find out if
+ * these skipped bits match our key perfectly, or if we will
+ * have to count on finding a matching prefix further down,
+ * because if we do, we would like to have some way of
+ * verifying the existence of such a prefix at this point.
+ */
+
+ /* The only thing we can do at this point is to verify that
+ * any such matching prefix can indeed be a prefix to our
+ * key, and if the bits in the node we are inspecting that
+ * do not match our key are not ZERO, this cannot be true.
+ * Thus, find out where there is a mismatch (before cn->pos)
+ * and verify that all the mismatching bits are zero in the
+ * new tnode's key.
+ */
+
+ /* Note: We aren't very concerned about the piece of the key
+ * that precede pn->pos+pn->bits, since these have already been
+ * checked. The bits after cn->pos aren't checked since these are
+ * by definition "unknown" at this point. Thus, what we want to
+ * see is if we are about to enter the "prefix matching" state,
+ * and in that case verify that the skipped bits that will prevail
+ * throughout this subtree are zero, as they have to be if we are
+ * to find a matching prefix.
+ */
+
+ node_prefix = MASK_PFX(cn->key, cn->pos);
+ key_prefix = MASK_PFX(key, cn->pos);
+ pref_mismatch = key_prefix^node_prefix;
+ mp = 0;
+
+ /* In short: If skipped bits in this node do not match the search
+ * key, enter the "prefix matching" state.directly.
+ */
+ if (pref_mismatch) {
+ while (!(pref_mismatch & (1<<(KEYLENGTH-1)))) {
+ mp++;
+ pref_mismatch = pref_mismatch <<1;
+ }
+ key_prefix = tkey_extract_bits(cn->key, mp, cn->pos-mp);
+
+ if (key_prefix != 0)
+ goto backtrace;
+
+ if (current_prefix_length >= cn->pos)
+ current_prefix_length=mp;
+ }
+#endif
+ pn = (struct tnode *)n; /* Descend */
+ chopped_off = 0;
+ continue;
+ }
+ if (IS_LEAF(n)) {
+ if( check_leaf(t, (struct leaf *)n, key, &plen, flp, res, &ret))
+ goto found;
+ }
+backtrace:
+ chopped_off++;
+
+ /* As zero don't change the child key (cindex) */
+ while ((chopped_off <= pn->bits) && !(cindex & (1<<(chopped_off-1)))) {
+ chopped_off++;
+ }
+
+ /* Decrease current_... with bits chopped off */
+ if (current_prefix_length > pn->pos + pn->bits - chopped_off)
+ current_prefix_length = pn->pos + pn->bits - chopped_off;
+
+ /*
+ * Either we do the actual chop off according or if we have
+ * chopped off all bits in this tnode walk up to our parent.
+ */
+
+ if(chopped_off <= pn->bits)
+ cindex &= ~(1 << (chopped_off-1));
+ else {
+ if( NODE_PARENT(pn) == NULL)
+ goto failed;
+
+ /* Get Child's index */
+ cindex = tkey_extract_bits(pn->key, NODE_PARENT(pn)->pos, NODE_PARENT(pn)->bits);
+ pn = NODE_PARENT(pn);
+ chopped_off = 0;
+
+#ifdef CONFIG_IP_FIB_TRIE_STATS
+ t->stats.backtrack++;
+#endif
+ goto backtrace;
+ }
+ }
+failed:
+ ret = 1;
+found:
+ read_unlock(&fib_lock);
+ return ret;
+}
+
+static int trie_leaf_remove(struct trie *t, t_key key)
+{
+ t_key cindex;
+ struct tnode *tp = NULL;
+ struct node *n = t->trie;
+ struct leaf *l;
+
+ if(trie_debug)
+ printk("entering trie_leaf_remove(%p)\n", n);
+
+ /* Note that in the case skipped bits, those bits are *not* checked!
+ * When we finish this, we will have NULL or a T_LEAF, and the
+ * T_LEAF may or may not match our key.
+ */
+
+ while (n != NULL && IS_TNODE(n)) {
+ struct tnode *tn = (struct tnode *) n;
+ check_tnode(tn);
+ n = tnode_get_child(tn ,tkey_extract_bits(key, tn->pos, tn->bits));
+
+ if(n && NODE_PARENT(n) != tn) {
+ printk("BUG tn=%p, n->parent=%p\n", tn, NODE_PARENT(n));
+ BUG();
+ }
+ }
+ l = (struct leaf *) n;
+
+ if(!n || !tkey_equals(l->key, key))
+ return 0;
+
+ /*
+ * Key found.
+ * Remove the leaf and rebalance the tree
+ */
+
+ t->revision++;
+ t->size--;
+
+ tp = NODE_PARENT(n);
+ tnode_free((struct tnode *) n);
+
+ if(tp) {
+ cindex = tkey_extract_bits(key, tp->pos, tp->bits);
+ put_child(t, (struct tnode *)tp, cindex, NULL);
+ t->trie = trie_rebalance(t, tp);
+ }
+ else
+ t->trie = NULL;
+
+ return 1;
+}
+
+static int
+fn_trie_delete(struct fib_table *tb, struct rtmsg *r, struct kern_rta *rta,
+ struct nlmsghdr *nlhdr, struct netlink_skb_parms *req)
+{
+ struct trie *t = (struct trie *) tb->tb_data;
+ u32 key, mask;
+ int plen = r->rtm_dst_len;
+ u8 tos = r->rtm_tos;
+ struct fib_alias *fa, *fa_to_delete;
+ struct list_head *fa_head;
+ struct leaf *l;
+
+ if (plen > 32)
+ return -EINVAL;
+
+ key = 0;
+ if (rta->rta_dst)
+ memcpy(&key, rta->rta_dst, 4);
+
+ key = ntohl(key);
+ mask = ntohl( inet_make_mask(plen) );
+
+ if(key & ~mask)
+ return -EINVAL;
+
+ key = key & mask;
+ l = fib_find_node(t, key);
+
+ if(!l)
+ return -ESRCH;
+
+ fa_head = get_fa_head(l, plen);
+ fa = fib_find_alias(fa_head, tos, 0);
+
+ if (!fa)
+ return -ESRCH;
+
+ if (trie_debug)
+ printk("Deleting %08x/%d tos=%d t=%p\n", key, plen, tos, t);
+
+ fa_to_delete = NULL;
+ fa_head = fa->fa_list.prev;
+ list_for_each_entry(fa, fa_head, fa_list) {
+ struct fib_info *fi = fa->fa_info;
+
+ if (fa->fa_tos != tos)
+ break;
+
+ if ((!r->rtm_type ||
+ fa->fa_type == r->rtm_type) &&
+ (r->rtm_scope == RT_SCOPE_NOWHERE ||
+ fa->fa_scope == r->rtm_scope) &&
+ (!r->rtm_protocol ||
+ fi->fib_protocol == r->rtm_protocol) &&
+ fib_nh_match(r, nlhdr, rta, fi) == 0) {
+ fa_to_delete = fa;
+ break;
+ }
+ }
+
+ if (fa_to_delete) {
+ int kill_li = 0;
+ struct leaf_info *li;
+
+ fa = fa_to_delete;
+ rtmsg_fib(RTM_DELROUTE, htonl(key), fa, plen, tb->tb_id, nlhdr, req);
+
+ l = fib_find_node(t, key);
+ li = find_leaf_info(&l->list, plen);
+
+ write_lock_bh(&fib_lock);
+
+ list_del(&fa->fa_list);
+
+ if(list_empty(fa_head)) {
+ hlist_del(&li->hlist);
+ kill_li = 1;
+ }
+ write_unlock_bh(&fib_lock);
+
+ if(kill_li)
+ free_leaf_info(li);
+
+ if(hlist_empty(&l->list))
+ trie_leaf_remove(t, key);
+
+ if (fa->fa_state & FA_S_ACCESSED)
+ rt_cache_flush(-1);
+
+ fn_free_alias(fa);
+ return 0;
+ }
+ return -ESRCH;
+}
+
+static int trie_flush_list(struct trie *t, struct list_head *head)
+{
+ struct fib_alias *fa, *fa_node;
+ int found = 0;
+
+ list_for_each_entry_safe(fa, fa_node, head, fa_list) {
+ struct fib_info *fi = fa->fa_info;
+
+ if (fi && (fi->fib_flags&RTNH_F_DEAD)) {
+
+ write_lock_bh(&fib_lock);
+ list_del(&fa->fa_list);
+ write_unlock_bh(&fib_lock);
+
+ fn_free_alias(fa);
+ found++;
+ }
+ }
+ return found;
+}
+
+static int trie_flush_leaf(struct trie *t, struct leaf *l)
+{
+ int found = 0;
+ struct hlist_head *lih = &l->list;
+ struct hlist_node *node, *tmp;
+ struct leaf_info *li = NULL;
+
+ hlist_for_each_entry_safe(li, node, tmp, lih, hlist) {
+
+ found += trie_flush_list(t, &li->falh);
+
+ if (list_empty(&li->falh)) {
+
+ write_lock_bh(&fib_lock);
+ hlist_del(&li->hlist);
+ write_unlock_bh(&fib_lock);
+
+ free_leaf_info(li);
+ }
+ }
+ return found;
+}
+
+static struct leaf *nextleaf(struct trie *t, struct leaf *thisleaf)
+{
+ struct node *c = (struct node *) thisleaf;
+ struct tnode *p;
+ int idx;
+
+ if(c == NULL) {
+ if(t->trie == NULL)
+ return NULL;
+
+ if (IS_LEAF(t->trie)) /* trie w. just a leaf */
+ return (struct leaf *) t->trie;
+
+ p = (struct tnode*) t->trie; /* Start */
+ }
+ else
+ p = (struct tnode *) NODE_PARENT(c);
+ while (p) {
+ int pos, last;
+
+ /* Find the next child of the parent */
+ if(c)
+ pos = 1 + tkey_extract_bits(c->key, p->pos, p->bits);
+ else
+ pos = 0;
+
+ last = 1 << p->bits;
+ for(idx = pos; idx < last ; idx++) {
+ if( p->child[idx]) {
+
+ /* Decend if tnode */
+
+ while (IS_TNODE(p->child[idx])) {
+ p = (struct tnode*) p->child[idx];
+ idx = 0;
+
+ /* Rightmost non-NULL branch */
+ if( p && IS_TNODE(p) )
+ while ( p->child[idx] == NULL && idx < (1 << p->bits) ) idx++;
+
+ /* Done with this tnode? */
+ if( idx >= (1 << p->bits) || p->child[idx] == NULL )
+ goto up;
+ }
+ return (struct leaf*) p->child[idx];
+ }
+ }
+up:
+ /* No more children go up one step */
+ c = (struct node*) p;
+ p = (struct tnode *) NODE_PARENT(p);
+ }
+ return NULL; /* Ready. Root of trie */
+}
+
+static int fn_trie_flush(struct fib_table *tb)
+{
+ struct trie *t = (struct trie *) tb->tb_data;
+ struct leaf *ll = NULL, *l = NULL;
+ int found = 0, h;
+
+ t->revision++;
+
+ for (h=0; (l = nextleaf(t, l)) != NULL; h++) {
+ found += trie_flush_leaf(t, l);
+
+ if (ll && hlist_empty(&ll->list))
+ trie_leaf_remove(t, ll->key);
+ ll = l;
+ }
+
+ if (ll && hlist_empty(&ll->list))
+ trie_leaf_remove(t, ll->key);
+
+ if(trie_debug)
+ printk("trie_flush found=%d\n", found);
+ return found;
+}
+
+static int trie_last_dflt=-1;
+
+static void
+fn_trie_select_default(struct fib_table *tb, const struct flowi *flp, struct fib_result *res)
+{
+ struct trie *t = (struct trie *) tb->tb_data;
+ int order, last_idx;
+ struct fib_info *fi = NULL;
+ struct fib_info *last_resort;
+ struct fib_alias *fa = NULL;
+ struct list_head *fa_head;
+ struct leaf *l;
+
+ last_idx = -1;
+ last_resort = NULL;
+ order = -1;
+
+ read_lock(&fib_lock);
+
+ l = fib_find_node(t, 0);
+ if(!l)
+ goto out;
+
+ fa_head = get_fa_head(l, 0);
+ if(!fa_head)
+ goto out;
+
+ if (list_empty(fa_head))
+ goto out;
+
+ list_for_each_entry(fa, fa_head, fa_list) {
+ struct fib_info *next_fi = fa->fa_info;
+
+ if (fa->fa_scope != res->scope ||
+ fa->fa_type != RTN_UNICAST)
+ continue;
+
+ if (next_fi->fib_priority > res->fi->fib_priority)
+ break;
+ if (!next_fi->fib_nh[0].nh_gw ||
+ next_fi->fib_nh[0].nh_scope != RT_SCOPE_LINK)
+ continue;
+ fa->fa_state |= FA_S_ACCESSED;
+
+ if (fi == NULL) {
+ if (next_fi != res->fi)
+ break;
+ } else if (!fib_detect_death(fi, order, &last_resort,
+ &last_idx, &trie_last_dflt)) {
+ if (res->fi)
+ fib_info_put(res->fi);
+ res->fi = fi;
+ atomic_inc(&fi->fib_clntref);
+ trie_last_dflt = order;
+ goto out;
+ }
+ fi = next_fi;
+ order++;
+ }
+ if (order <= 0 || fi == NULL) {
+ trie_last_dflt = -1;
+ goto out;
+ }
+
+ if (!fib_detect_death(fi, order, &last_resort, &last_idx, &trie_last_dflt)) {
+ if (res->fi)
+ fib_info_put(res->fi);
+ res->fi = fi;
+ atomic_inc(&fi->fib_clntref);
+ trie_last_dflt = order;
+ goto out;
+ }
+ if (last_idx >= 0) {
+ if (res->fi)
+ fib_info_put(res->fi);
+ res->fi = last_resort;
+ if (last_resort)
+ atomic_inc(&last_resort->fib_clntref);
+ }
+ trie_last_dflt = last_idx;
+ out:;
+ read_unlock(&fib_lock);
+}
+
+static int fn_trie_dump_fa(t_key key, int plen, struct list_head *fah, struct fib_table *tb,
+ struct sk_buff *skb, struct netlink_callback *cb)
+{
+ int i, s_i;
+ struct fib_alias *fa;
+
+ u32 xkey=htonl(key);
+
+ s_i=cb->args[3];
+ i = 0;
+
+ list_for_each_entry(fa, fah, fa_list) {
+ if (i < s_i) {
+ i++;
+ continue;
+ }
+ if (fa->fa_info->fib_nh == NULL) {
+ printk("Trie error _fib_nh=NULL in fa[%d] k=%08x plen=%d\n", i, key, plen);
+ i++;
+ continue;
+ }
+ if (fa->fa_info == NULL) {
+ printk("Trie error fa_info=NULL in fa[%d] k=%08x plen=%d\n", i, key, plen);
+ i++;
+ continue;
+ }
+
+ if (fib_dump_info(skb, NETLINK_CB(cb->skb).pid,
+ cb->nlh->nlmsg_seq,
+ RTM_NEWROUTE,
+ tb->tb_id,
+ fa->fa_type,
+ fa->fa_scope,
+ &xkey,
+ plen,
+ fa->fa_tos,
+ fa->fa_info) < 0) {
+ cb->args[3] = i;
+ return -1;
+ }
+ i++;
+ }
+ cb->args[3]=i;
+ return skb->len;
+}
+
+static int fn_trie_dump_plen(struct trie *t, int plen, struct fib_table *tb, struct sk_buff *skb,
+ struct netlink_callback *cb)
+{
+ int h, s_h;
+ struct list_head *fa_head;
+ struct leaf *l = NULL;
+ s_h=cb->args[2];
+
+ for (h=0; (l = nextleaf(t, l)) != NULL; h++) {
+
+ if (h < s_h)
+ continue;
+ if (h > s_h)
+ memset(&cb->args[3], 0,
+ sizeof(cb->args) - 3*sizeof(cb->args[0]));
+
+ fa_head = get_fa_head(l, plen);
+
+ if(!fa_head)
+ continue;
+
+ if(list_empty(fa_head))
+ continue;
+
+ if (fn_trie_dump_fa(l->key, plen, fa_head, tb, skb, cb)<0) {
+ cb->args[2]=h;
+ return -1;
+ }
+ }
+ cb->args[2]=h;
+ return skb->len;
+}
+
+static int fn_trie_dump(struct fib_table *tb, struct sk_buff *skb, struct netlink_callback *cb)
+{
+ int m, s_m;
+ struct trie *t = (struct trie *) tb->tb_data;
+
+ s_m = cb->args[1];
+
+ read_lock(&fib_lock);
+ for (m=0; m<=32; m++) {
+
+ if (m < s_m)
+ continue;
+ if (m > s_m)
+ memset(&cb->args[2], 0,
+ sizeof(cb->args) - 2*sizeof(cb->args[0]));
+
+ if (fn_trie_dump_plen(t, 32-m, tb, skb, cb)<0) {
+ cb->args[1] = m;
+ goto out;
+ }
+ }
+ read_unlock(&fib_lock);
+ cb->args[1] = m;
+ return skb->len;
+ out:
+ read_unlock(&fib_lock);
+ return -1;
+}
+
+/* Fix more generic FIB names for init later */
+
+#ifdef CONFIG_IP_MULTIPLE_TABLES
+struct fib_table * fib_hash_init(int id)
+#else
+struct fib_table * __init fib_hash_init(int id)
+#endif
+{
+ struct fib_table *tb;
+ struct trie *t;
+
+ if (fn_alias_kmem == NULL)
+ fn_alias_kmem = kmem_cache_create("ip_fib_alias",
+ sizeof(struct fib_alias),
+ 0, SLAB_HWCACHE_ALIGN,
+ NULL, NULL);
+
+ tb = kmalloc(sizeof(struct fib_table) + sizeof(struct trie),
+ GFP_KERNEL);
+ if (tb == NULL)
+ return NULL;
+
+ tb->tb_id = id;
+ tb->tb_lookup = fn_trie_lookup;
+ tb->tb_insert = fn_trie_insert;
+ tb->tb_delete = fn_trie_delete;
+ tb->tb_flush = fn_trie_flush;
+ tb->tb_select_default = fn_trie_select_default;
+ tb->tb_dump = fn_trie_dump;
+ memset(tb->tb_data, 0, sizeof(struct trie));
+
+ t = (struct trie *) tb->tb_data;
+
+ trie_init(t);
+
+ if (id == RT_TABLE_LOCAL)
+ trie_local=t;
+ else if (id == RT_TABLE_MAIN)
+ trie_main=t;
+
+ if (id == RT_TABLE_LOCAL)
+ printk("IPv4 FIB: Using LC-trie version %s\n", VERSION);
+
+ return tb;
+}
+
+/* Trie dump functions */
+
+static void putspace_seq(struct seq_file *seq, int n)
+{
+ while (n--) seq_printf(seq, " ");
+}
+
+static void printbin_seq(struct seq_file *seq, unsigned int v, int bits)
+{
+ while (bits--)
+ seq_printf(seq, "%s", (v & (1<<bits))?"1":"0");
+}
+
+static void printnode_seq(struct seq_file *seq, int indent, struct node *n,
+ int pend, int cindex, int bits)
+{
+ putspace_seq(seq, indent);
+ if (IS_LEAF(n))
+ seq_printf(seq, "|");
+ else
+ seq_printf(seq, "+");
+ if (bits) {
+ seq_printf(seq, "%d/", cindex);
+ printbin_seq(seq, cindex, bits);
+ seq_printf(seq, ": ");
+ }
+ else
+ seq_printf(seq, "<root>: ");
+ seq_printf(seq, "%s:%p ", IS_LEAF(n)?"Leaf":"Internal node", n);
+
+ if (IS_LEAF(n))
+ seq_printf(seq, "key=%d.%d.%d.%d\n",
+ n->key >> 24, (n->key >> 16) % 256, (n->key >> 8) % 256, n->key % 256);
+ else {
+ int plen=((struct tnode *)n)->pos;
+ t_key prf=MASK_PFX(n->key, plen);
+ seq_printf(seq, "key=%d.%d.%d.%d/%d\n",
+ prf >> 24, (prf >> 16) % 256, (prf >> 8) % 256, prf % 256, plen);
+ }
+ if (IS_LEAF(n)) {
+ struct leaf *l=(struct leaf *)n;
+ struct fib_alias *fa;
+ int i;
+ for (i=32; i>=0; i--)
+ if(find_leaf_info(&l->list, i)) {
+
+ struct list_head *fa_head = get_fa_head(l, i);
+
+ if(!fa_head)
+ continue;
+
+ if(list_empty(fa_head))
+ continue;
+
+ putspace_seq(seq, indent+2);
+ seq_printf(seq, "{/%d...dumping}\n", i);
+
+
+ list_for_each_entry(fa, fa_head, fa_list) {
+ putspace_seq(seq, indent+2);
+ if (fa->fa_info->fib_nh == NULL) {
+ seq_printf(seq, "Error _fib_nh=NULL\n");
+ continue;
+ }
+ if (fa->fa_info == NULL) {
+ seq_printf(seq, "Error fa_info=NULL\n");
+ continue;
+ }
+
+ seq_printf(seq, "{type=%d scope=%d TOS=%d}\n",
+ fa->fa_type,
+ fa->fa_scope,
+ fa->fa_tos);
+ }
+ }
+ }
+ else if (IS_TNODE(n)) {
+ struct tnode *tn=(struct tnode *)n;
+ putspace_seq(seq, indent); seq_printf(seq, "| ");
+ seq_printf(seq, "{key prefix=%08x/", tn->key&TKEY_GET_MASK(0, tn->pos));
+ printbin_seq(seq, tkey_extract_bits(tn->key, 0, tn->pos), tn->pos);
+ seq_printf(seq, "}\n");
+ putspace_seq(seq, indent); seq_printf(seq, "| ");
+ seq_printf(seq, "{pos=%d", tn->pos);
+ seq_printf(seq, " (skip=%d bits)", tn->pos - pend);
+ seq_printf(seq, " bits=%d (%u children)}\n", tn->bits, (1 << tn->bits));
+ putspace_seq(seq, indent); seq_printf(seq, "| ");
+ seq_printf(seq, "{empty=%d full=%d}\n", tn->empty_children, tn->full_children);
+ }
+}
+
+static void trie_dump_seq(struct seq_file *seq, struct trie *t)
+{
+ struct node *n=t->trie;
+ int cindex=0;
+ int indent=1;
+ int pend=0;
+ int depth = 0;
+
+ read_lock(&fib_lock);
+
+ seq_printf(seq, "------ trie_dump of t=%p ------\n", t);
+ if (n) {
+ printnode_seq(seq, indent, n, pend, cindex, 0);
+ if (IS_TNODE(n)) {
+ struct tnode *tn=(struct tnode *)n;
+ pend = tn->pos+tn->bits;
+ putspace_seq(seq, indent); seq_printf(seq, "\\--\n");
+ indent += 3;
+ depth++;
+
+ while (tn && cindex < (1 << tn->bits)) {
+ if (tn->child[cindex]) {
+
+ /* Got a child */
+
+ printnode_seq(seq, indent, tn->child[cindex], pend, cindex, tn->bits);
+ if (IS_LEAF(tn->child[cindex])) {
+ cindex++;
+
+ }
+ else {
+ /*
+ * New tnode. Decend one level
+ */
+
+ depth++;
+ n=tn->child[cindex];
+ tn=(struct tnode *)n;
+ pend=tn->pos+tn->bits;
+ putspace_seq(seq, indent); seq_printf(seq, "\\--\n");
+ indent+=3;
+ cindex=0;
+ }
+ }
+ else
+ cindex++;
+
+ /*
+ * Test if we are done
+ */
+
+ while (cindex >= (1 << tn->bits)) {
+
+ /*
+ * Move upwards and test for root
+ * pop off all traversed nodes
+ */
+
+ if (NODE_PARENT(tn) == NULL) {
+ tn = NULL;
+ n = NULL;
+ break;
+ }
+ else {
+ cindex = tkey_extract_bits(tn->key, NODE_PARENT(tn)->pos, NODE_PARENT(tn)->bits);
+ tn = NODE_PARENT(tn);
+ cindex++;
+ n=(struct node *)tn;
+ pend=tn->pos+tn->bits;
+ indent-=3;
+ depth--;
+ }
+ }
+ }
+ }
+ else n = NULL;
+ }
+ else seq_printf(seq, "------ trie is empty\n");
+
+ read_unlock(&fib_lock);
+}
+
+static struct trie_stat *trie_stat_new(void)
+{
+ struct trie_stat *s = kmalloc(sizeof(struct trie_stat), GFP_KERNEL);
+ int i;
+
+ if(s) {
+ s->totdepth = 0;
+ s->maxdepth = 0;
+ s->tnodes = 0;
+ s->leaves = 0;
+ s->nullpointers = 0;
+
+ for(i=0; i< MAX_CHILDS; i++)
+ s->nodesizes[i] = 0;
+ }
+ return s;
+}
+
+static struct trie_stat *trie_collect_stats(struct trie *t)
+{
+ struct node *n=t->trie;
+ struct trie_stat *s = trie_stat_new();
+ int cindex = 0;
+ int indent = 1;
+ int pend = 0;
+ int depth = 0;
+
+ read_lock(&fib_lock);
+
+ if (s) {
+ if (n) {
+ if (IS_TNODE(n)) {
+ struct tnode *tn = (struct tnode *)n;
+ pend=tn->pos+tn->bits;
+ indent += 3;
+ s->nodesizes[tn->bits]++;
+ depth++;
+
+ while (tn && cindex < (1 << tn->bits)) {
+ if (tn->child[cindex]) {
+ /* Got a child */
+
+ if (IS_LEAF(tn->child[cindex])) {
+ cindex++;
+
+ /* stats */
+ if (depth > s->maxdepth)
+ s->maxdepth = depth;
+ s->totdepth += depth;
+ s->leaves++;
+ }
+
+ else {
+ /*
+ * New tnode. Decend one level
+ */
+
+ s->tnodes++;
+ s->nodesizes[tn->bits]++;
+ depth++;
+
+ n = tn->child[cindex];
+ tn = (struct tnode *)n;
+ pend = tn->pos+tn->bits;
+
+ indent += 3;
+ cindex = 0;
+ }
+ }
+ else {
+ cindex++;
+ s->nullpointers++;
+ }
+
+ /*
+ * Test if we are done
+ */
+
+ while (cindex >= (1 << tn->bits)) {
+
+ /*
+ * Move upwards and test for root
+ * pop off all traversed nodes
+ */
+
+
+ if (NODE_PARENT(tn) == NULL) {
+ tn = NULL;
+ n = NULL;
+ break;
+ }
+ else {
+ cindex = tkey_extract_bits(tn->key, NODE_PARENT(tn)->pos, NODE_PARENT(tn)->bits);
+ tn = NODE_PARENT(tn);
+ cindex++;
+ n = (struct node *)tn;
+ pend=tn->pos+tn->bits;
+ indent -= 3;
+ depth--;
+ }
+ }
+ }
+ }
+ else n = NULL;
+ }
+ }
+
+ read_unlock(&fib_lock);
+ return s;
+}
+
+#ifdef CONFIG_PROC_FS
+
+static struct fib_alias *fib_triestat_get_first(struct seq_file *seq)
+{
+ return NULL;
+}
+
+static struct fib_alias *fib_triestat_get_next(struct seq_file *seq)
+{
+ return NULL;
+}
+
+static void *fib_triestat_seq_start(struct seq_file *seq, loff_t *pos)
+{
+ void *v = NULL;
+
+ if (ip_fib_main_table)
+ v = *pos ? fib_triestat_get_next(seq) : SEQ_START_TOKEN;
+ return v;
+}
+
+static void *fib_triestat_seq_next(struct seq_file *seq, void *v, loff_t *pos)
+{
+ ++*pos;
+ return v == SEQ_START_TOKEN ? fib_triestat_get_first(seq) : fib_triestat_get_next(seq);
+}
+
+static void fib_triestat_seq_stop(struct seq_file *seq, void *v)
+{
+
+}
+
+/*
+ * This outputs /proc/net/fib_triestats
+ *
+ * It always works in backward compatibility mode.
+ * The format of the file is not supposed to be changed.
+ */
+
+static void collect_and_show(struct trie *t, struct seq_file *seq)
+{
+ int bytes = 0; /* How many bytes are used, a ref is 4 bytes */
+ int i, max, pointers;
+ struct trie_stat *stat;
+ int avdepth;
+
+ stat = trie_collect_stats(t);
+
+ bytes=0;
+ seq_printf(seq, "trie=%p\n", t);
+
+ if (stat) {
+ if (stat->leaves)
+ avdepth=stat->totdepth*100 / stat->leaves;
+ else
+ avdepth=0;
+ seq_printf(seq, "Aver depth: %d.%02d\n", avdepth / 100, avdepth % 100 );
+ seq_printf(seq, "Max depth: %4d\n", stat->maxdepth);
+
+ seq_printf(seq, "Leaves: %d\n", stat->leaves);
+ bytes += sizeof(struct leaf) * stat->leaves;
+ seq_printf(seq, "Internal nodes: %d\n", stat->tnodes);
+ bytes += sizeof(struct tnode) * stat->tnodes;
+
+ max = MAX_CHILDS-1;
+
+ while (max >= 0 && stat->nodesizes[max] == 0)
+ max--;
+ pointers = 0;
+
+ for (i = 1; i <= max; i++)
+ if (stat->nodesizes[i] != 0) {
+ seq_printf(seq, " %d: %d", i, stat->nodesizes[i]);
+ pointers += (1<<i) * stat->nodesizes[i];
+ }
+ seq_printf(seq, "\n");
+ seq_printf(seq, "Pointers: %d\n", pointers);
+ bytes += sizeof(struct node *) * pointers;
+ seq_printf(seq, "Null ptrs: %d\n", stat->nullpointers);
+ seq_printf(seq, "Total size: %d kB\n", bytes / 1024);
+
+ kfree(stat);
+ }
+
+#ifdef CONFIG_IP_FIB_TRIE_STATS
+ seq_printf(seq, "Counters:\n---------\n");
+ seq_printf(seq,"gets = %d\n", t->stats.gets);
+ seq_printf(seq,"backtracks = %d\n", t->stats.backtrack);
+ seq_printf(seq,"semantic match passed = %d\n", t->stats.semantic_match_passed);
+ seq_printf(seq,"semantic match miss = %d\n", t->stats.semantic_match_miss);
+ seq_printf(seq,"null node hit= %d\n", t->stats.null_node_hit);
+#ifdef CLEAR_STATS
+ memset(&(t->stats), 0, sizeof(t->stats));
+#endif
+#endif /* CONFIG_IP_FIB_TRIE_STATS */
+}
+
+static int fib_triestat_seq_show(struct seq_file *seq, void *v)
+{
+ char bf[128];
+
+ if (v == SEQ_START_TOKEN) {
+ seq_printf(seq, "Basic info: size of leaf: %Zd bytes, size of tnode: %Zd bytes.\n",
+ sizeof(struct leaf), sizeof(struct tnode));
+ if (trie_local)
+ collect_and_show(trie_local, seq);
+
+ if (trie_main)
+ collect_and_show(trie_main, seq);
+ }
+ else {
+ snprintf(bf, sizeof(bf),
+ "*\t%08X\t%08X", 200, 400);
+
+ seq_printf(seq, "%-127s\n", bf);
+ }
+ return 0;
+}
+
+static struct seq_operations fib_triestat_seq_ops = {
+ .start = fib_triestat_seq_start,
+ .next = fib_triestat_seq_next,
+ .stop = fib_triestat_seq_stop,
+ .show = fib_triestat_seq_show,
+};
+
+static int fib_triestat_seq_open(struct inode *inode, struct file *file)
+{
+ struct seq_file *seq;
+ int rc = -ENOMEM;
+
+ rc = seq_open(file, &fib_triestat_seq_ops);
+ if (rc)
+ goto out_kfree;
+
+ seq = file->private_data;
+out:
+ return rc;
+out_kfree:
+ goto out;
+}
+
+static struct file_operations fib_triestat_seq_fops = {
+ .owner = THIS_MODULE,
+ .open = fib_triestat_seq_open,
+ .read = seq_read,
+ .llseek = seq_lseek,
+ .release = seq_release_private,
+};
+
+int __init fib_stat_proc_init(void)
+{
+ if (!proc_net_fops_create("fib_triestat", S_IRUGO, &fib_triestat_seq_fops))
+ return -ENOMEM;
+ return 0;
+}
+
+void __init fib_stat_proc_exit(void)
+{
+ proc_net_remove("fib_triestat");
+}
+
+static struct fib_alias *fib_trie_get_first(struct seq_file *seq)
+{
+ return NULL;
+}
+
+static struct fib_alias *fib_trie_get_next(struct seq_file *seq)
+{
+ return NULL;
+}
+
+static void *fib_trie_seq_start(struct seq_file *seq, loff_t *pos)
+{
+ void *v = NULL;
+
+ if (ip_fib_main_table)
+ v = *pos ? fib_trie_get_next(seq) : SEQ_START_TOKEN;
+ return v;
+}
+
+static void *fib_trie_seq_next(struct seq_file *seq, void *v, loff_t *pos)
+{
+ ++*pos;
+ return v == SEQ_START_TOKEN ? fib_trie_get_first(seq) : fib_trie_get_next(seq);
+}
+
+static void fib_trie_seq_stop(struct seq_file *seq, void *v)
+{
+
+}
+
+/*
+ * This outputs /proc/net/fib_trie.
+ *
+ * It always works in backward compatibility mode.
+ * The format of the file is not supposed to be changed.
+ */
+
+static int fib_trie_seq_show(struct seq_file *seq, void *v)
+{
+ char bf[128];
+
+ if (v == SEQ_START_TOKEN) {
+ if (trie_local)
+ trie_dump_seq(seq, trie_local);
+
+ if (trie_main)
+ trie_dump_seq(seq, trie_main);
+ }
+
+ else {
+ snprintf(bf, sizeof(bf),
+ "*\t%08X\t%08X", 200, 400);
+ seq_printf(seq, "%-127s\n", bf);
+ }
+
+ return 0;
+}
+
+static struct seq_operations fib_trie_seq_ops = {
+ .start = fib_trie_seq_start,
+ .next = fib_trie_seq_next,
+ .stop = fib_trie_seq_stop,
+ .show = fib_trie_seq_show,
+};
+
+static int fib_trie_seq_open(struct inode *inode, struct file *file)
+{
+ struct seq_file *seq;
+ int rc = -ENOMEM;
+
+ rc = seq_open(file, &fib_trie_seq_ops);
+ if (rc)
+ goto out_kfree;
+
+ seq = file->private_data;
+out:
+ return rc;
+out_kfree:
+ goto out;
+}
+
+static struct file_operations fib_trie_seq_fops = {
+ .owner = THIS_MODULE,
+ .open = fib_trie_seq_open,
+ .read = seq_read,
+ .llseek = seq_lseek,
+ .release = seq_release_private,
+};
+
+int __init fib_proc_init(void)
+{
+ if (!proc_net_fops_create("fib_trie", S_IRUGO, &fib_trie_seq_fops))
+ return -ENOMEM;
+ return 0;
+}
+
+void __init fib_proc_exit(void)
+{
+ proc_net_remove("fib_trie");
+}
+
+#endif /* CONFIG_PROC_FS */