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Diffstat (limited to 'net/ipv4/fib_trie.c')
| -rw-r--r-- | net/ipv4/fib_trie.c | 2454 |
1 files changed, 2454 insertions, 0 deletions
diff --git a/net/ipv4/fib_trie.c b/net/ipv4/fib_trie.c new file mode 100644 index 0000000..0671569 --- /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) < 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 */ |