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-rw-r--r--net/ipv4/fib_trie.c2636
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diff --git a/net/ipv4/fib_trie.c b/net/ipv4/fib_trie.c
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+++ b/net/ipv4/fib_trie.c
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+/*
+ * 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 described in:
+ *
+ * An experimental study of compression methods for dynamic tries
+ * Stefan Nilsson and Matti Tikkanen. Algorithmica, 33(1):19-33, 2002.
+ * http://www.csc.kth.se/~snilsson/software/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
+ *
+ *
+ * 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.
+ *
+ * Substantial contributions to this work comes from:
+ *
+ * David S. Miller, <davem@davemloft.net>
+ * Stephen Hemminger <shemminger@osdl.org>
+ * Paul E. McKenney <paulmck@us.ibm.com>
+ * Patrick McHardy <kaber@trash.net>
+ */
+
+#define VERSION "0.409"
+
+#include <asm/uaccess.h>
+#include <asm/system.h>
+#include <linux/bitops.h>
+#include <linux/types.h>
+#include <linux/kernel.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/inetdevice.h>
+#include <linux/netdevice.h>
+#include <linux/if_arp.h>
+#include <linux/proc_fs.h>
+#include <linux/rcupdate.h>
+#include <linux/skbuff.h>
+#include <linux/netlink.h>
+#include <linux/init.h>
+#include <linux/list.h>
+#include <linux/slab.h>
+#include <linux/prefetch.h>
+#include <net/net_namespace.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"
+
+#define MAX_STAT_DEPTH 32
+
+#define KEYLENGTH (8*sizeof(t_key))
+
+typedef unsigned int t_key;
+
+#define T_TNODE 0
+#define T_LEAF 1
+#define NODE_TYPE_MASK 0x1UL
+#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 rt_trie_node {
+ unsigned long parent;
+ t_key key;
+};
+
+struct leaf {
+ unsigned long parent;
+ t_key key;
+ struct hlist_head list;
+ struct rcu_head rcu;
+};
+
+struct leaf_info {
+ struct hlist_node hlist;
+ struct rcu_head rcu;
+ int plen;
+ struct list_head falh;
+};
+
+struct tnode {
+ unsigned long parent;
+ t_key key;
+ unsigned char pos; /* 2log(KEYLENGTH) bits needed */
+ unsigned char bits; /* 2log(KEYLENGTH) bits needed */
+ unsigned int full_children; /* KEYLENGTH bits needed */
+ unsigned int empty_children; /* KEYLENGTH bits needed */
+ union {
+ struct rcu_head rcu;
+ struct work_struct work;
+ struct tnode *tnode_free;
+ };
+ struct rt_trie_node __rcu *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;
+ unsigned int resize_node_skipped;
+};
+#endif
+
+struct trie_stat {
+ unsigned int totdepth;
+ unsigned int maxdepth;
+ unsigned int tnodes;
+ unsigned int leaves;
+ unsigned int nullpointers;
+ unsigned int prefixes;
+ unsigned int nodesizes[MAX_STAT_DEPTH];
+};
+
+struct trie {
+ struct rt_trie_node __rcu *trie;
+#ifdef CONFIG_IP_FIB_TRIE_STATS
+ struct trie_use_stats stats;
+#endif
+};
+
+static void put_child(struct trie *t, struct tnode *tn, int i, struct rt_trie_node *n);
+static void tnode_put_child_reorg(struct tnode *tn, int i, struct rt_trie_node *n,
+ int wasfull);
+static struct rt_trie_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);
+/* tnodes to free after resize(); protected by RTNL */
+static struct tnode *tnode_free_head;
+static size_t tnode_free_size;
+
+/*
+ * synchronize_rcu after call_rcu for that many pages; it should be especially
+ * useful before resizing the root node with PREEMPT_NONE configs; the value was
+ * obtained experimentally, aiming to avoid visible slowdown.
+ */
+static const int sync_pages = 128;
+
+static struct kmem_cache *fn_alias_kmem __read_mostly;
+static struct kmem_cache *trie_leaf_kmem __read_mostly;
+
+/*
+ * caller must hold RTNL
+ */
+static inline struct tnode *node_parent(const struct rt_trie_node *node)
+{
+ unsigned long parent;
+
+ parent = rcu_dereference_index_check(node->parent, lockdep_rtnl_is_held());
+
+ return (struct tnode *)(parent & ~NODE_TYPE_MASK);
+}
+
+/*
+ * caller must hold RCU read lock or RTNL
+ */
+static inline struct tnode *node_parent_rcu(const struct rt_trie_node *node)
+{
+ unsigned long parent;
+
+ parent = rcu_dereference_index_check(node->parent, rcu_read_lock_held() ||
+ lockdep_rtnl_is_held());
+
+ return (struct tnode *)(parent & ~NODE_TYPE_MASK);
+}
+
+/* Same as rcu_assign_pointer
+ * but that macro() assumes that value is a pointer.
+ */
+static inline void node_set_parent(struct rt_trie_node *node, struct tnode *ptr)
+{
+ smp_wmb();
+ node->parent = (unsigned long)ptr | NODE_TYPE(node);
+}
+
+/*
+ * caller must hold RTNL
+ */
+static inline struct rt_trie_node *tnode_get_child(const struct tnode *tn, unsigned int i)
+{
+ BUG_ON(i >= 1U << tn->bits);
+
+ return rtnl_dereference(tn->child[i]);
+}
+
+/*
+ * caller must hold RCU read lock or RTNL
+ */
+static inline struct rt_trie_node *tnode_get_child_rcu(const struct tnode *tn, unsigned int i)
+{
+ BUG_ON(i >= 1U << tn->bits);
+
+ return rcu_dereference_rtnl(tn->child[i]);
+}
+
+static inline int tnode_child_length(const struct tnode *tn)
+{
+ return 1 << tn->bits;
+}
+
+static inline t_key mask_pfx(t_key k, unsigned int l)
+{
+ return (l == 0) ? 0 : k >> (KEYLENGTH-l) << (KEYLENGTH-l);
+}
+
+static inline t_key tkey_extract_bits(t_key a, unsigned int offset, unsigned 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;
+}
+
+/*
+ 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
+ necessitated 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 inline void check_tnode(const struct tnode *tn)
+{
+ WARN_ON(tn && tn->pos+tn->bits > 32);
+}
+
+static const int halve_threshold = 25;
+static const int inflate_threshold = 50;
+static const int halve_threshold_root = 15;
+static const int inflate_threshold_root = 30;
+
+static void __alias_free_mem(struct rcu_head *head)
+{
+ struct fib_alias *fa = container_of(head, struct fib_alias, rcu);
+ kmem_cache_free(fn_alias_kmem, fa);
+}
+
+static inline void alias_free_mem_rcu(struct fib_alias *fa)
+{
+ call_rcu(&fa->rcu, __alias_free_mem);
+}
+
+static void __leaf_free_rcu(struct rcu_head *head)
+{
+ struct leaf *l = container_of(head, struct leaf, rcu);
+ kmem_cache_free(trie_leaf_kmem, l);
+}
+
+static inline void free_leaf(struct leaf *l)
+{
+ call_rcu_bh(&l->rcu, __leaf_free_rcu);
+}
+
+static inline void free_leaf_info(struct leaf_info *leaf)
+{
+ kfree_rcu(leaf, rcu);
+}
+
+static struct tnode *tnode_alloc(size_t size)
+{
+ if (size <= PAGE_SIZE)
+ return kzalloc(size, GFP_KERNEL);
+ else
+ return vzalloc(size);
+}
+
+static void __tnode_vfree(struct work_struct *arg)
+{
+ struct tnode *tn = container_of(arg, struct tnode, work);
+ vfree(tn);
+}
+
+static void __tnode_free_rcu(struct rcu_head *head)
+{
+ struct tnode *tn = container_of(head, struct tnode, rcu);
+ size_t size = sizeof(struct tnode) +
+ (sizeof(struct rt_trie_node *) << tn->bits);
+
+ if (size <= PAGE_SIZE)
+ kfree(tn);
+ else {
+ INIT_WORK(&tn->work, __tnode_vfree);
+ schedule_work(&tn->work);
+ }
+}
+
+static inline void tnode_free(struct tnode *tn)
+{
+ if (IS_LEAF(tn))
+ free_leaf((struct leaf *) tn);
+ else
+ call_rcu(&tn->rcu, __tnode_free_rcu);
+}
+
+static void tnode_free_safe(struct tnode *tn)
+{
+ BUG_ON(IS_LEAF(tn));
+ tn->tnode_free = tnode_free_head;
+ tnode_free_head = tn;
+ tnode_free_size += sizeof(struct tnode) +
+ (sizeof(struct rt_trie_node *) << tn->bits);
+}
+
+static void tnode_free_flush(void)
+{
+ struct tnode *tn;
+
+ while ((tn = tnode_free_head)) {
+ tnode_free_head = tn->tnode_free;
+ tn->tnode_free = NULL;
+ tnode_free(tn);
+ }
+
+ if (tnode_free_size >= PAGE_SIZE * sync_pages) {
+ tnode_free_size = 0;
+ synchronize_rcu();
+ }
+}
+
+static struct leaf *leaf_new(void)
+{
+ struct leaf *l = kmem_cache_alloc(trie_leaf_kmem, GFP_KERNEL);
+ if (l) {
+ l->parent = 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);
+ if (li) {
+ li->plen = plen;
+ INIT_LIST_HEAD(&li->falh);
+ }
+ return li;
+}
+
+static struct tnode *tnode_new(t_key key, int pos, int bits)
+{
+ size_t sz = sizeof(struct tnode) + (sizeof(struct rt_trie_node *) << bits);
+ struct tnode *tn = tnode_alloc(sz);
+
+ if (tn) {
+ tn->parent = T_TNODE;
+ tn->pos = pos;
+ tn->bits = bits;
+ tn->key = key;
+ tn->full_children = 0;
+ tn->empty_children = 1<<bits;
+ }
+
+ pr_debug("AT %p s=%zu %zu\n", tn, sizeof(struct tnode),
+ sizeof(struct rt_trie_node) << bits);
+ return tn;
+}
+
+/*
+ * 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(const struct tnode *tn, const struct rt_trie_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 rt_trie_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 rt_trie_node *n,
+ int wasfull)
+{
+ struct rt_trie_node *chi = rtnl_dereference(tn->child[i]);
+ int isfull;
+
+ BUG_ON(i >= 1<<tn->bits);
+
+ /* 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);
+
+ rcu_assign_pointer(tn->child[i], n);
+}
+
+#define MAX_WORK 10
+static struct rt_trie_node *resize(struct trie *t, struct tnode *tn)
+{
+ int i;
+ struct tnode *old_tn;
+ int inflate_threshold_use;
+ int halve_threshold_use;
+ int max_work;
+
+ if (!tn)
+ return NULL;
+
+ pr_debug("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_safe(tn);
+ return NULL;
+ }
+ /* One child */
+ if (tn->empty_children == tnode_child_length(tn) - 1)
+ goto one_child;
+ /*
+ * 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);
+
+ /* Keep root node larger */
+
+ if (!node_parent((struct rt_trie_node *)tn)) {
+ inflate_threshold_use = inflate_threshold_root;
+ halve_threshold_use = halve_threshold_root;
+ } else {
+ inflate_threshold_use = inflate_threshold;
+ halve_threshold_use = halve_threshold;
+ }
+
+ max_work = MAX_WORK;
+ while ((tn->full_children > 0 && max_work-- &&
+ 50 * (tn->full_children + tnode_child_length(tn)
+ - tn->empty_children)
+ >= inflate_threshold_use * tnode_child_length(tn))) {
+
+ old_tn = tn;
+ tn = inflate(t, tn);
+
+ if (IS_ERR(tn)) {
+ tn = old_tn;
+#ifdef CONFIG_IP_FIB_TRIE_STATS
+ t->stats.resize_node_skipped++;
+#endif
+ break;
+ }
+ }
+
+ check_tnode(tn);
+
+ /* Return if at least one inflate is run */
+ if (max_work != MAX_WORK)
+ return (struct rt_trie_node *) tn;
+
+ /*
+ * Halve as long as the number of empty children in this
+ * node is above threshold.
+ */
+
+ max_work = MAX_WORK;
+ while (tn->bits > 1 && max_work-- &&
+ 100 * (tnode_child_length(tn) - tn->empty_children) <
+ halve_threshold_use * tnode_child_length(tn)) {
+
+ old_tn = tn;
+ tn = halve(t, tn);
+ if (IS_ERR(tn)) {
+ tn = old_tn;
+#ifdef CONFIG_IP_FIB_TRIE_STATS
+ t->stats.resize_node_skipped++;
+#endif
+ break;
+ }
+ }
+
+
+ /* Only one child remains */
+ if (tn->empty_children == tnode_child_length(tn) - 1) {
+one_child:
+ for (i = 0; i < tnode_child_length(tn); i++) {
+ struct rt_trie_node *n;
+
+ n = rtnl_dereference(tn->child[i]);
+ if (!n)
+ continue;
+
+ /* compress one level */
+
+ node_set_parent(n, NULL);
+ tnode_free_safe(tn);
+ return n;
+ }
+ }
+ return (struct rt_trie_node *) tn;
+}
+
+
+static void tnode_clean_free(struct tnode *tn)
+{
+ int i;
+ struct tnode *tofree;
+
+ for (i = 0; i < tnode_child_length(tn); i++) {
+ tofree = (struct tnode *)rtnl_dereference(tn->child[i]);
+ if (tofree)
+ tnode_free(tofree);
+ }
+ tnode_free(tn);
+}
+
+static struct tnode *inflate(struct trie *t, struct tnode *tn)
+{
+ struct tnode *oldtnode = tn;
+ int olen = tnode_child_length(tn);
+ int i;
+
+ pr_debug("In inflate\n");
+
+ tn = tnode_new(oldtnode->key, oldtnode->pos, oldtnode->bits + 1);
+
+ if (!tn)
+ return ERR_PTR(-ENOMEM);
+
+ /*
+ * Preallocate and store tnodes before the actual work so we
+ * don't get into an inconsistent state if memory allocation
+ * fails. In case of failure we return the oldnode and inflate
+ * of tnode is ignored.
+ */
+
+ for (i = 0; i < olen; i++) {
+ struct tnode *inode;
+
+ inode = (struct tnode *) tnode_get_child(oldtnode, i);
+ if (inode &&
+ IS_TNODE(inode) &&
+ inode->pos == oldtnode->pos + oldtnode->bits &&
+ inode->bits > 1) {
+ struct tnode *left, *right;
+ t_key m = ~0U << (KEYLENGTH - 1) >> inode->pos;
+
+ left = tnode_new(inode->key&(~m), inode->pos + 1,
+ inode->bits - 1);
+ if (!left)
+ goto nomem;
+
+ right = tnode_new(inode->key|m, inode->pos + 1,
+ inode->bits - 1);
+
+ if (!right) {
+ tnode_free(left);
+ goto nomem;
+ }
+
+ put_child(t, tn, 2*i, (struct rt_trie_node *) left);
+ put_child(t, tn, 2*i+1, (struct rt_trie_node *) right);
+ }
+ }
+
+ for (i = 0; i < olen; i++) {
+ struct tnode *inode;
+ struct rt_trie_node *node = tnode_get_child(oldtnode, i);
+ struct tnode *left, *right;
+ int size, j;
+
+ /* 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,
+ oldtnode->pos + oldtnode->bits,
+ 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, rtnl_dereference(inode->child[0]));
+ put_child(t, tn, 2*i+1, rtnl_dereference(inode->child[1]));
+
+ tnode_free_safe(inode);
+ continue;
+ }
+
+ /* An internal node with more than two children */
+
+ /* 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)
+ */
+
+ /* Use the old key, but set the new significant
+ * bit to zero.
+ */
+
+ left = (struct tnode *) tnode_get_child(tn, 2*i);
+ put_child(t, tn, 2*i, NULL);
+
+ BUG_ON(!left);
+
+ right = (struct tnode *) tnode_get_child(tn, 2*i+1);
+ put_child(t, tn, 2*i+1, NULL);
+
+ BUG_ON(!right);
+
+ size = tnode_child_length(left);
+ for (j = 0; j < size; j++) {
+ put_child(t, left, j, rtnl_dereference(inode->child[j]));
+ put_child(t, right, j, rtnl_dereference(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_safe(inode);
+ }
+ tnode_free_safe(oldtnode);
+ return tn;
+nomem:
+ tnode_clean_free(tn);
+ return ERR_PTR(-ENOMEM);
+}
+
+static struct tnode *halve(struct trie *t, struct tnode *tn)
+{
+ struct tnode *oldtnode = tn;
+ struct rt_trie_node *left, *right;
+ int i;
+ int olen = tnode_child_length(tn);
+
+ pr_debug("In halve\n");
+
+ tn = tnode_new(oldtnode->key, oldtnode->pos, oldtnode->bits - 1);
+
+ if (!tn)
+ return ERR_PTR(-ENOMEM);
+
+ /*
+ * Preallocate and store tnodes before the actual work so we
+ * don't get into an inconsistent state if memory allocation
+ * fails. In case of failure we return the oldnode and halve
+ * of tnode is ignored.
+ */
+
+ for (i = 0; i < olen; i += 2) {
+ left = tnode_get_child(oldtnode, i);
+ right = tnode_get_child(oldtnode, i+1);
+
+ /* Two nonempty children */
+ if (left && right) {
+ struct tnode *newn;
+
+ newn = tnode_new(left->key, tn->pos + tn->bits, 1);
+
+ if (!newn)
+ goto nomem;
+
+ put_child(t, tn, i/2, (struct rt_trie_node *)newn);
+ }
+
+ }
+
+ for (i = 0; i < olen; i += 2) {
+ struct tnode *newBinNode;
+
+ 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);
+ continue;
+ }
+
+ if (right == NULL) {
+ put_child(t, tn, i/2, left);
+ continue;
+ }
+
+ /* Two nonempty children */
+ newBinNode = (struct tnode *) tnode_get_child(tn, i/2);
+ put_child(t, tn, i/2, NULL);
+ put_child(t, newBinNode, 0, left);
+ put_child(t, newBinNode, 1, right);
+ put_child(t, tn, i/2, resize(t, newBinNode));
+ }
+ tnode_free_safe(oldtnode);
+ return tn;
+nomem:
+ tnode_clean_free(tn);
+ return ERR_PTR(-ENOMEM);
+}
+
+/* readside must use rcu_read_lock currently dump routines
+ via get_fa_head and dump */
+
+static struct leaf_info *find_leaf_info(struct leaf *l, int plen)
+{
+ struct hlist_head *head = &l->list;
+ struct hlist_node *node;
+ struct leaf_info *li;
+
+ hlist_for_each_entry_rcu(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 leaf_info *li = find_leaf_info(l, plen);
+
+ if (!li)
+ return NULL;
+
+ return &li->falh;
+}
+
+static void insert_leaf_info(struct hlist_head *head, struct leaf_info *new)
+{
+ struct leaf_info *li = NULL, *last = NULL;
+ struct hlist_node *node;
+
+ if (hlist_empty(head)) {
+ hlist_add_head_rcu(&new->hlist, head);
+ } else {
+ hlist_for_each_entry(li, node, head, hlist) {
+ if (new->plen > li->plen)
+ break;
+
+ last = li;
+ }
+ if (last)
+ hlist_add_after_rcu(&last->hlist, &new->hlist);
+ else
+ hlist_add_before_rcu(&new->hlist, &li->hlist);
+ }
+}
+
+/* rcu_read_lock needs to be hold by caller from readside */
+
+static struct leaf *
+fib_find_node(struct trie *t, u32 key)
+{
+ int pos;
+ struct tnode *tn;
+ struct rt_trie_node *n;
+
+ pos = 0;
+ n = rcu_dereference_rtnl(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_rcu(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))
+ return (struct leaf *)n;
+
+ return NULL;
+}
+
+static void trie_rebalance(struct trie *t, struct tnode *tn)
+{
+ int wasfull;
+ t_key cindex, key;
+ struct tnode *tp;
+
+ key = tn->key;
+
+ while (tn != NULL && (tp = node_parent((struct rt_trie_node *)tn)) != NULL) {
+ 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 rt_trie_node *)tn, wasfull);
+
+ tp = node_parent((struct rt_trie_node *) tn);
+ if (!tp)
+ rcu_assign_pointer(t->trie, (struct rt_trie_node *)tn);
+
+ tnode_free_flush();
+ if (!tp)
+ break;
+ tn = tp;
+ }
+
+ /* Handle last (top) tnode */
+ if (IS_TNODE(tn))
+ tn = (struct tnode *)resize(t, (struct tnode *)tn);
+
+ rcu_assign_pointer(t->trie, (struct rt_trie_node *)tn);
+ tnode_free_flush();
+}
+
+/* only used from updater-side */
+
+static struct list_head *fib_insert_node(struct trie *t, u32 key, int plen)
+{
+ int pos, newpos;
+ struct tnode *tp = NULL, *tn = NULL;
+ struct rt_trie_node *n;
+ struct leaf *l;
+ int missbit;
+ struct list_head *fa_head = NULL;
+ struct leaf_info *li;
+ t_key cindex;
+
+ pos = 0;
+ n = rtnl_dereference(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));
+
+ BUG_ON(n && node_parent(n) != tn);
+ } else
+ break;
+ }
+
+ /*
+ * n ----> NULL, LEAF or TNODE
+ *
+ * tp is n's (parent) ----> NULL or TNODE
+ */
+
+ BUG_ON(tp && IS_LEAF(tp));
+
+ /* Case 1: n is a leaf. Compare prefixes */
+
+ if (n != NULL && IS_LEAF(n) && tkey_equals(key, n->key)) {
+ l = (struct leaf *) n;
+ li = leaf_info_new(plen);
+
+ if (!li)
+ return NULL;
+
+ fa_head = &li->falh;
+ insert_leaf_info(&l->list, li);
+ goto done;
+ }
+ l = leaf_new();
+
+ if (!l)
+ return NULL;
+
+ l->key = key;
+ li = leaf_info_new(plen);
+
+ if (!li) {
+ free_leaf(l);
+ return NULL;
+ }
+
+ fa_head = &li->falh;
+ insert_leaf_info(&l->list, li);
+
+ if (t->trie && n == NULL) {
+ /* Case 2: n is NULL, and will just insert a new leaf */
+
+ node_set_parent((struct rt_trie_node *)l, tp);
+
+ cindex = tkey_extract_bits(key, tp->pos, tp->bits);
+ put_child(t, (struct tnode *)tp, cindex, (struct rt_trie_node *)l);
+ } else {
+ /* Case 3: n is a LEAF or a TNODE and the key doesn't match. */
+ /*
+ * 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) {
+ free_leaf_info(li);
+ free_leaf(l);
+ return NULL;
+ }
+
+ node_set_parent((struct rt_trie_node *)tn, tp);
+
+ missbit = tkey_extract_bits(key, newpos, 1);
+ put_child(t, tn, missbit, (struct rt_trie_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 rt_trie_node *)tn);
+ } else {
+ rcu_assign_pointer(t->trie, (struct rt_trie_node *)tn);
+ tp = tn;
+ }
+ }
+
+ if (tp && tp->pos + tp->bits > 32)
+ pr_warning("fib_trie"
+ " tp=%p pos=%d, bits=%d, key=%0x plen=%d\n",
+ tp, tp->pos, tp->bits, key, plen);
+
+ /* Rebalance the trie */
+
+ trie_rebalance(t, tp);
+done:
+ return fa_head;
+}
+
+/*
+ * Caller must hold RTNL.
+ */
+int fib_table_insert(struct fib_table *tb, struct fib_config *cfg)
+{
+ 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 = cfg->fc_dst_len;
+ u8 tos = cfg->fc_tos;
+ u32 key, mask;
+ int err;
+ struct leaf *l;
+
+ if (plen > 32)
+ return -EINVAL;
+
+ key = ntohl(cfg->fc_dst);
+
+ pr_debug("Insert table=%u %08x/%d\n", tb->tb_id, key, plen);
+
+ mask = ntohl(inet_make_mask(plen));
+
+ if (key & ~mask)
+ return -EINVAL;
+
+ key = key & mask;
+
+ fi = fib_create_info(cfg);
+ if (IS_ERR(fi)) {
+ err = PTR_ERR(fi);
+ 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_tos == tos &&
+ fa->fa_info->fib_priority == fi->fib_priority) {
+ struct fib_alias *fa_first, *fa_match;
+
+ err = -EEXIST;
+ if (cfg->fc_nlflags & NLM_F_EXCL)
+ goto out;
+
+ /* We have 2 goals:
+ * 1. Find exact match for type, scope, fib_info to avoid
+ * duplicate routes
+ * 2. Find next 'fa' (or head), NLM_F_APPEND inserts before it
+ */
+ fa_match = NULL;
+ fa_first = fa;
+ fa = list_entry(fa->fa_list.prev, struct fib_alias, fa_list);
+ list_for_each_entry_continue(fa, fa_head, fa_list) {
+ if (fa->fa_tos != tos)
+ break;
+ if (fa->fa_info->fib_priority != fi->fib_priority)
+ break;
+ if (fa->fa_type == cfg->fc_type &&
+ fa->fa_info == fi) {
+ fa_match = fa;
+ break;
+ }
+ }
+
+ if (cfg->fc_nlflags & NLM_F_REPLACE) {
+ struct fib_info *fi_drop;
+ u8 state;
+
+ fa = fa_first;
+ if (fa_match) {
+ if (fa == fa_match)
+ err = 0;
+ goto out;
+ }
+ err = -ENOBUFS;
+ new_fa = kmem_cache_alloc(fn_alias_kmem, GFP_KERNEL);
+ if (new_fa == NULL)
+ goto out;
+
+ fi_drop = fa->fa_info;
+ new_fa->fa_tos = fa->fa_tos;
+ new_fa->fa_info = fi;
+ new_fa->fa_type = cfg->fc_type;
+ state = fa->fa_state;
+ new_fa->fa_state = state & ~FA_S_ACCESSED;
+
+ list_replace_rcu(&fa->fa_list, &new_fa->fa_list);
+ alias_free_mem_rcu(fa);
+
+ fib_release_info(fi_drop);
+ if (state & FA_S_ACCESSED)
+ rt_cache_flush(cfg->fc_nlinfo.nl_net, -1);
+ rtmsg_fib(RTM_NEWROUTE, htonl(key), new_fa, plen,
+ tb->tb_id, &cfg->fc_nlinfo, NLM_F_REPLACE);
+
+ goto succeeded;
+ }
+ /* Error if we find a perfect match which
+ * uses the same scope, type, and nexthop
+ * information.
+ */
+ if (fa_match)
+ goto out;
+
+ if (!(cfg->fc_nlflags & NLM_F_APPEND))
+ fa = fa_first;
+ }
+ err = -ENOENT;
+ if (!(cfg->fc_nlflags & NLM_F_CREATE))
+ goto out;
+
+ err = -ENOBUFS;
+ new_fa = kmem_cache_alloc(fn_alias_kmem, GFP_KERNEL);
+ if (new_fa == NULL)
+ goto out;
+
+ new_fa->fa_info = fi;
+ new_fa->fa_tos = tos;
+ new_fa->fa_type = cfg->fc_type;
+ new_fa->fa_state = 0;
+ /*
+ * Insert new entry to the list.
+ */
+
+ if (!fa_head) {
+ fa_head = fib_insert_node(t, key, plen);
+ if (unlikely(!fa_head)) {
+ err = -ENOMEM;
+ goto out_free_new_fa;
+ }
+ }
+
+ if (!plen)
+ tb->tb_num_default++;
+
+ list_add_tail_rcu(&new_fa->fa_list,
+ (fa ? &fa->fa_list : fa_head));
+
+ rt_cache_flush(cfg->fc_nlinfo.nl_net, -1);
+ rtmsg_fib(RTM_NEWROUTE, htonl(key), new_fa, plen, tb->tb_id,
+ &cfg->fc_nlinfo, 0);
+succeeded:
+ return 0;
+
+out_free_new_fa:
+ kmem_cache_free(fn_alias_kmem, new_fa);
+out:
+ fib_release_info(fi);
+err:
+ return err;
+}
+
+/* should be called with rcu_read_lock */
+static int check_leaf(struct fib_table *tb, struct trie *t, struct leaf *l,
+ t_key key, const struct flowi4 *flp,
+ struct fib_result *res, int fib_flags)
+{
+ struct leaf_info *li;
+ struct hlist_head *hhead = &l->list;
+ struct hlist_node *node;
+
+ hlist_for_each_entry_rcu(li, node, hhead, hlist) {
+ struct fib_alias *fa;
+ int plen = li->plen;
+ __be32 mask = inet_make_mask(plen);
+
+ if (l->key != (key & ntohl(mask)))
+ continue;
+
+ list_for_each_entry_rcu(fa, &li->falh, fa_list) {
+ struct fib_info *fi = fa->fa_info;
+ int nhsel, err;
+
+ if (fa->fa_tos && fa->fa_tos != flp->flowi4_tos)
+ continue;
+ if (fi->fib_dead)
+ continue;
+ if (fa->fa_info->fib_scope < flp->flowi4_scope)
+ continue;
+ fib_alias_accessed(fa);
+ err = fib_props[fa->fa_type].error;
+ if (err) {
+#ifdef CONFIG_IP_FIB_TRIE_STATS
+ t->stats.semantic_match_passed++;
+#endif
+ return err;
+ }
+ if (fi->fib_flags & RTNH_F_DEAD)
+ continue;
+ for (nhsel = 0; nhsel < fi->fib_nhs; nhsel++) {
+ const struct fib_nh *nh = &fi->fib_nh[nhsel];
+
+ if (nh->nh_flags & RTNH_F_DEAD)
+ continue;
+ if (flp->flowi4_oif && flp->flowi4_oif != nh->nh_oif)
+ continue;
+
+#ifdef CONFIG_IP_FIB_TRIE_STATS
+ t->stats.semantic_match_passed++;
+#endif
+ res->prefixlen = plen;
+ res->nh_sel = nhsel;
+ res->type = fa->fa_type;
+ res->scope = fa->fa_info->fib_scope;
+ res->fi = fi;
+ res->table = tb;
+ res->fa_head = &li->falh;
+ if (!(fib_flags & FIB_LOOKUP_NOREF))
+ atomic_inc(&res->fi->fib_clntref);
+ return 0;
+ }
+ }
+
+#ifdef CONFIG_IP_FIB_TRIE_STATS
+ t->stats.semantic_match_miss++;
+#endif
+ }
+
+ return 1;
+}
+
+int fib_table_lookup(struct fib_table *tb, const struct flowi4 *flp,
+ struct fib_result *res, int fib_flags)
+{
+ struct trie *t = (struct trie *) tb->tb_data;
+ int ret;
+ struct rt_trie_node *n;
+ struct tnode *pn;
+ unsigned int pos, bits;
+ t_key key = ntohl(flp->daddr);
+ unsigned int chopped_off;
+ t_key cindex = 0;
+ unsigned int current_prefix_length = KEYLENGTH;
+ struct tnode *cn;
+ t_key pref_mismatch;
+
+ rcu_read_lock();
+
+ n = rcu_dereference(t->trie);
+ if (!n)
+ goto failed;
+
+#ifdef CONFIG_IP_FIB_TRIE_STATS
+ t->stats.gets++;
+#endif
+
+ /* Just a leaf? */
+ if (IS_LEAF(n)) {
+ ret = check_leaf(tb, t, (struct leaf *)n, key, flp, res, fib_flags);
+ goto found;
+ }
+
+ 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_rcu(pn, cindex);
+
+ if (n == NULL) {
+#ifdef CONFIG_IP_FIB_TRIE_STATS
+ t->stats.null_node_hit++;
+#endif
+ goto backtrace;
+ }
+
+ if (IS_LEAF(n)) {
+ ret = check_leaf(tb, t, (struct leaf *)n, key, flp, res, fib_flags);
+ if (ret > 0)
+ goto backtrace;
+ goto found;
+ }
+
+ cn = (struct tnode *)n;
+
+ /*
+ * 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)
+ || !(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.
+ */
+
+ pref_mismatch = mask_pfx(cn->key ^ key, cn->pos);
+
+ /*
+ * In short: If skipped bits in this node do not match
+ * the search key, enter the "prefix matching"
+ * state.directly.
+ */
+ if (pref_mismatch) {
+ int mp = KEYLENGTH - fls(pref_mismatch);
+
+ if (tkey_extract_bits(cn->key, mp, cn->pos - mp) != 0)
+ goto backtrace;
+
+ if (current_prefix_length >= cn->pos)
+ current_prefix_length = mp;
+ }
+
+ pn = (struct tnode *)n; /* Descend */
+ chopped_off = 0;
+ continue;
+
+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 {
+ struct tnode *parent = node_parent_rcu((struct rt_trie_node *) pn);
+ if (!parent)
+ goto failed;
+
+ /* Get Child's index */
+ cindex = tkey_extract_bits(pn->key, parent->pos, parent->bits);
+ pn = parent;
+ chopped_off = 0;
+
+#ifdef CONFIG_IP_FIB_TRIE_STATS
+ t->stats.backtrack++;
+#endif
+ goto backtrace;
+ }
+ }
+failed:
+ ret = 1;
+found:
+ rcu_read_unlock();
+ return ret;
+}
+
+/*
+ * Remove the leaf and return parent.
+ */
+static void trie_leaf_remove(struct trie *t, struct leaf *l)
+{
+ struct tnode *tp = node_parent((struct rt_trie_node *) l);
+
+ pr_debug("entering trie_leaf_remove(%p)\n", l);
+
+ if (tp) {
+ t_key cindex = tkey_extract_bits(l->key, tp->pos, tp->bits);
+ put_child(t, (struct tnode *)tp, cindex, NULL);
+ trie_rebalance(t, tp);
+ } else
+ rcu_assign_pointer(t->trie, NULL);
+
+ free_leaf(l);
+}
+
+/*
+ * Caller must hold RTNL.
+ */
+int fib_table_delete(struct fib_table *tb, struct fib_config *cfg)
+{
+ struct trie *t = (struct trie *) tb->tb_data;
+ u32 key, mask;
+ int plen = cfg->fc_dst_len;
+ u8 tos = cfg->fc_tos;
+ struct fib_alias *fa, *fa_to_delete;
+ struct list_head *fa_head;
+ struct leaf *l;
+ struct leaf_info *li;
+
+ if (plen > 32)
+ return -EINVAL;
+
+ key = ntohl(cfg->fc_dst);
+ 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;
+
+ pr_debug("Deleting %08x/%d tos=%d t=%p\n", key, plen, tos, t);
+
+ fa_to_delete = NULL;
+ fa = list_entry(fa->fa_list.prev, struct fib_alias, fa_list);
+ list_for_each_entry_continue(fa, fa_head, fa_list) {
+ struct fib_info *fi = fa->fa_info;
+
+ if (fa->fa_tos != tos)
+ break;
+
+ if ((!cfg->fc_type || fa->fa_type == cfg->fc_type) &&
+ (cfg->fc_scope == RT_SCOPE_NOWHERE ||
+ fa->fa_info->fib_scope == cfg->fc_scope) &&
+ (!cfg->fc_prefsrc ||
+ fi->fib_prefsrc == cfg->fc_prefsrc) &&
+ (!cfg->fc_protocol ||
+ fi->fib_protocol == cfg->fc_protocol) &&
+ fib_nh_match(cfg, fi) == 0) {
+ fa_to_delete = fa;
+ break;
+ }
+ }
+
+ if (!fa_to_delete)
+ return -ESRCH;
+
+ fa = fa_to_delete;
+ rtmsg_fib(RTM_DELROUTE, htonl(key), fa, plen, tb->tb_id,
+ &cfg->fc_nlinfo, 0);
+
+ l = fib_find_node(t, key);
+ li = find_leaf_info(l, plen);
+
+ list_del_rcu(&fa->fa_list);
+
+ if (!plen)
+ tb->tb_num_default--;
+
+ if (list_empty(fa_head)) {
+ hlist_del_rcu(&li->hlist);
+ free_leaf_info(li);
+ }
+
+ if (hlist_empty(&l->list))
+ trie_leaf_remove(t, l);
+
+ if (fa->fa_state & FA_S_ACCESSED)
+ rt_cache_flush(cfg->fc_nlinfo.nl_net, -1);
+
+ fib_release_info(fa->fa_info);
+ alias_free_mem_rcu(fa);
+ return 0;
+}
+
+static int trie_flush_list(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)) {
+ list_del_rcu(&fa->fa_list);
+ fib_release_info(fa->fa_info);
+ alias_free_mem_rcu(fa);
+ found++;
+ }
+ }
+ return found;
+}
+
+static int trie_flush_leaf(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(&li->falh);
+
+ if (list_empty(&li->falh)) {
+ hlist_del_rcu(&li->hlist);
+ free_leaf_info(li);
+ }
+ }
+ return found;
+}
+
+/*
+ * Scan for the next right leaf starting at node p->child[idx]
+ * Since we have back pointer, no recursion necessary.
+ */
+static struct leaf *leaf_walk_rcu(struct tnode *p, struct rt_trie_node *c)
+{
+ do {
+ t_key idx;
+
+ if (c)
+ idx = tkey_extract_bits(c->key, p->pos, p->bits) + 1;
+ else
+ idx = 0;
+
+ while (idx < 1u << p->bits) {
+ c = tnode_get_child_rcu(p, idx++);
+ if (!c)
+ continue;
+
+ if (IS_LEAF(c)) {
+ prefetch(rcu_dereference_rtnl(p->child[idx]));
+ return (struct leaf *) c;
+ }
+
+ /* Rescan start scanning in new node */
+ p = (struct tnode *) c;
+ idx = 0;
+ }
+
+ /* Node empty, walk back up to parent */
+ c = (struct rt_trie_node *) p;
+ } while ((p = node_parent_rcu(c)) != NULL);
+
+ return NULL; /* Root of trie */
+}
+
+static struct leaf *trie_firstleaf(struct trie *t)
+{
+ struct tnode *n = (struct tnode *)rcu_dereference_rtnl(t->trie);
+
+ if (!n)
+ return NULL;
+
+ if (IS_LEAF(n)) /* trie is just a leaf */
+ return (struct leaf *) n;
+
+ return leaf_walk_rcu(n, NULL);
+}
+
+static struct leaf *trie_nextleaf(struct leaf *l)
+{
+ struct rt_trie_node *c = (struct rt_trie_node *) l;
+ struct tnode *p = node_parent_rcu(c);
+
+ if (!p)
+ return NULL; /* trie with just one leaf */
+
+ return leaf_walk_rcu(p, c);
+}
+
+static struct leaf *trie_leafindex(struct trie *t, int index)
+{
+ struct leaf *l = trie_firstleaf(t);
+
+ while (l && index-- > 0)
+ l = trie_nextleaf(l);
+
+ return l;
+}
+
+
+/*
+ * Caller must hold RTNL.
+ */
+int fib_table_flush(struct fib_table *tb)
+{
+ struct trie *t = (struct trie *) tb->tb_data;
+ struct leaf *l, *ll = NULL;
+ int found = 0;
+
+ for (l = trie_firstleaf(t); l; l = trie_nextleaf(l)) {
+ found += trie_flush_leaf(l);
+
+ if (ll && hlist_empty(&ll->list))
+ trie_leaf_remove(t, ll);
+ ll = l;
+ }
+
+ if (ll && hlist_empty(&ll->list))
+ trie_leaf_remove(t, ll);
+
+ pr_debug("trie_flush found=%d\n", found);
+ return found;
+}
+
+void fib_free_table(struct fib_table *tb)
+{
+ kfree(tb);
+}
+
+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;
+ __be32 xkey = htonl(key);
+
+ s_i = cb->args[5];
+ i = 0;
+
+ /* rcu_read_lock is hold by caller */
+
+ list_for_each_entry_rcu(fa, fah, fa_list) {
+ if (i < s_i) {
+ i++;
+ continue;
+ }
+
+ if (fib_dump_info(skb, NETLINK_CB(cb->skb).pid,
+ cb->nlh->nlmsg_seq,
+ RTM_NEWROUTE,
+ tb->tb_id,
+ fa->fa_type,
+ xkey,
+ plen,
+ fa->fa_tos,
+ fa->fa_info, NLM_F_MULTI) < 0) {
+ cb->args[5] = i;
+ return -1;
+ }
+ i++;
+ }
+ cb->args[5] = i;
+ return skb->len;
+}
+
+static int fn_trie_dump_leaf(struct leaf *l, struct fib_table *tb,
+ struct sk_buff *skb, struct netlink_callback *cb)
+{
+ struct leaf_info *li;
+ struct hlist_node *node;
+ int i, s_i;
+
+ s_i = cb->args[4];
+ i = 0;
+
+ /* rcu_read_lock is hold by caller */
+ hlist_for_each_entry_rcu(li, node, &l->list, hlist) {
+ if (i < s_i) {
+ i++;
+ continue;
+ }
+
+ if (i > s_i)
+ cb->args[5] = 0;
+
+ if (list_empty(&li->falh))
+ continue;
+
+ if (fn_trie_dump_fa(l->key, li->plen, &li->falh, tb, skb, cb) < 0) {
+ cb->args[4] = i;
+ return -1;
+ }
+ i++;
+ }
+
+ cb->args[4] = i;
+ return skb->len;
+}
+
+int fib_table_dump(struct fib_table *tb, struct sk_buff *skb,
+ struct netlink_callback *cb)
+{
+ struct leaf *l;
+ struct trie *t = (struct trie *) tb->tb_data;
+ t_key key = cb->args[2];
+ int count = cb->args[3];
+
+ rcu_read_lock();
+ /* Dump starting at last key.
+ * Note: 0.0.0.0/0 (ie default) is first key.
+ */
+ if (count == 0)
+ l = trie_firstleaf(t);
+ else {
+ /* Normally, continue from last key, but if that is missing
+ * fallback to using slow rescan
+ */
+ l = fib_find_node(t, key);
+ if (!l)
+ l = trie_leafindex(t, count);
+ }
+
+ while (l) {
+ cb->args[2] = l->key;
+ if (fn_trie_dump_leaf(l, tb, skb, cb) < 0) {
+ cb->args[3] = count;
+ rcu_read_unlock();
+ return -1;
+ }
+
+ ++count;
+ l = trie_nextleaf(l);
+ memset(&cb->args[4], 0,
+ sizeof(cb->args) - 4*sizeof(cb->args[0]));
+ }
+ cb->args[3] = count;
+ rcu_read_unlock();
+
+ return skb->len;
+}
+
+void __init fib_trie_init(void)
+{
+ fn_alias_kmem = kmem_cache_create("ip_fib_alias",
+ sizeof(struct fib_alias),
+ 0, SLAB_PANIC, NULL);
+
+ trie_leaf_kmem = kmem_cache_create("ip_fib_trie",
+ max(sizeof(struct leaf),
+ sizeof(struct leaf_info)),
+ 0, SLAB_PANIC, NULL);
+}
+
+
+struct fib_table *fib_trie_table(u32 id)
+{
+ struct fib_table *tb;
+ struct trie *t;
+
+ tb = kmalloc(sizeof(struct fib_table) + sizeof(struct trie),
+ GFP_KERNEL);
+ if (tb == NULL)
+ return NULL;
+
+ tb->tb_id = id;
+ tb->tb_default = -1;
+ tb->tb_num_default = 0;
+
+ t = (struct trie *) tb->tb_data;
+ memset(t, 0, sizeof(*t));
+
+ return tb;
+}
+
+#ifdef CONFIG_PROC_FS
+/* Depth first Trie walk iterator */
+struct fib_trie_iter {
+ struct seq_net_private p;
+ struct fib_table *tb;
+ struct tnode *tnode;
+ unsigned int index;
+ unsigned int depth;
+};
+
+static struct rt_trie_node *fib_trie_get_next(struct fib_trie_iter *iter)
+{
+ struct tnode *tn = iter->tnode;
+ unsigned int cindex = iter->index;
+ struct tnode *p;
+
+ /* A single entry routing table */
+ if (!tn)
+ return NULL;
+
+ pr_debug("get_next iter={node=%p index=%d depth=%d}\n",
+ iter->tnode, iter->index, iter->depth);
+rescan:
+ while (cindex < (1<<tn->bits)) {
+ struct rt_trie_node *n = tnode_get_child_rcu(tn, cindex);
+
+ if (n) {
+ if (IS_LEAF(n)) {
+ iter->tnode = tn;
+ iter->index = cindex + 1;
+ } else {
+ /* push down one level */
+ iter->tnode = (struct tnode *) n;
+ iter->index = 0;
+ ++iter->depth;
+ }
+ return n;
+ }
+
+ ++cindex;
+ }
+
+ /* Current node exhausted, pop back up */
+ p = node_parent_rcu((struct rt_trie_node *)tn);
+ if (p) {
+ cindex = tkey_extract_bits(tn->key, p->pos, p->bits)+1;
+ tn = p;
+ --iter->depth;
+ goto rescan;
+ }
+
+ /* got root? */
+ return NULL;
+}
+
+static struct rt_trie_node *fib_trie_get_first(struct fib_trie_iter *iter,
+ struct trie *t)
+{
+ struct rt_trie_node *n;
+
+ if (!t)
+ return NULL;
+
+ n = rcu_dereference(t->trie);
+ if (!n)
+ return NULL;
+
+ if (IS_TNODE(n)) {
+ iter->tnode = (struct tnode *) n;
+ iter->index = 0;
+ iter->depth = 1;
+ } else {
+ iter->tnode = NULL;
+ iter->index = 0;
+ iter->depth = 0;
+ }
+
+ return n;
+}
+
+static void trie_collect_stats(struct trie *t, struct trie_stat *s)
+{
+ struct rt_trie_node *n;
+ struct fib_trie_iter iter;
+
+ memset(s, 0, sizeof(*s));
+
+ rcu_read_lock();
+ for (n = fib_trie_get_first(&iter, t); n; n = fib_trie_get_next(&iter)) {
+ if (IS_LEAF(n)) {
+ struct leaf *l = (struct leaf *)n;
+ struct leaf_info *li;
+ struct hlist_node *tmp;
+
+ s->leaves++;
+ s->totdepth += iter.depth;
+ if (iter.depth > s->maxdepth)
+ s->maxdepth = iter.depth;
+
+ hlist_for_each_entry_rcu(li, tmp, &l->list, hlist)
+ ++s->prefixes;
+ } else {
+ const struct tnode *tn = (const struct tnode *) n;
+ int i;
+
+ s->tnodes++;
+ if (tn->bits < MAX_STAT_DEPTH)
+ s->nodesizes[tn->bits]++;
+
+ for (i = 0; i < (1<<tn->bits); i++)
+ if (!tn->child[i])
+ s->nullpointers++;
+ }
+ }
+ rcu_read_unlock();
+}
+
+/*
+ * This outputs /proc/net/fib_triestats
+ */
+static void trie_show_stats(struct seq_file *seq, struct trie_stat *stat)
+{
+ unsigned int i, max, pointers, bytes, avdepth;
+
+ if (stat->leaves)
+ avdepth = stat->totdepth*100 / stat->leaves;
+ else
+ avdepth = 0;
+
+ seq_printf(seq, "\tAver depth: %u.%02d\n",
+ avdepth / 100, avdepth % 100);
+ seq_printf(seq, "\tMax depth: %u\n", stat->maxdepth);
+
+ seq_printf(seq, "\tLeaves: %u\n", stat->leaves);
+ bytes = sizeof(struct leaf) * stat->leaves;
+
+ seq_printf(seq, "\tPrefixes: %u\n", stat->prefixes);
+ bytes += sizeof(struct leaf_info) * stat->prefixes;
+
+ seq_printf(seq, "\tInternal nodes: %u\n\t", stat->tnodes);
+ bytes += sizeof(struct tnode) * stat->tnodes;
+
+ max = MAX_STAT_DEPTH;
+ while (max > 0 && stat->nodesizes[max-1] == 0)
+ max--;
+
+ pointers = 0;
+ for (i = 1; i <= max; i++)
+ if (stat->nodesizes[i] != 0) {
+ seq_printf(seq, " %u: %u", i, stat->nodesizes[i]);
+ pointers += (1<<i) * stat->nodesizes[i];
+ }
+ seq_putc(seq, '\n');
+ seq_printf(seq, "\tPointers: %u\n", pointers);
+
+ bytes += sizeof(struct rt_trie_node *) * pointers;
+ seq_printf(seq, "Null ptrs: %u\n", stat->nullpointers);
+ seq_printf(seq, "Total size: %u kB\n", (bytes + 1023) / 1024);
+}
+
+#ifdef CONFIG_IP_FIB_TRIE_STATS
+static void trie_show_usage(struct seq_file *seq,
+ const struct trie_use_stats *stats)
+{
+ seq_printf(seq, "\nCounters:\n---------\n");
+ seq_printf(seq, "gets = %u\n", stats->gets);
+ seq_printf(seq, "backtracks = %u\n", stats->backtrack);
+ seq_printf(seq, "semantic match passed = %u\n",
+ stats->semantic_match_passed);
+ seq_printf(seq, "semantic match miss = %u\n",
+ stats->semantic_match_miss);
+ seq_printf(seq, "null node hit= %u\n", stats->null_node_hit);
+ seq_printf(seq, "skipped node resize = %u\n\n",
+ stats->resize_node_skipped);
+}
+#endif /* CONFIG_IP_FIB_TRIE_STATS */
+
+static void fib_table_print(struct seq_file *seq, struct fib_table *tb)
+{
+ if (tb->tb_id == RT_TABLE_LOCAL)
+ seq_puts(seq, "Local:\n");
+ else if (tb->tb_id == RT_TABLE_MAIN)
+ seq_puts(seq, "Main:\n");
+ else
+ seq_printf(seq, "Id %d:\n", tb->tb_id);
+}
+
+
+static int fib_triestat_seq_show(struct seq_file *seq, void *v)
+{
+ struct net *net = (struct net *)seq->private;
+ unsigned int h;
+
+ seq_printf(seq,
+ "Basic info: size of leaf:"
+ " %Zd bytes, size of tnode: %Zd bytes.\n",
+ sizeof(struct leaf), sizeof(struct tnode));
+
+ for (h = 0; h < FIB_TABLE_HASHSZ; h++) {
+ struct hlist_head *head = &net->ipv4.fib_table_hash[h];
+ struct hlist_node *node;
+ struct fib_table *tb;
+
+ hlist_for_each_entry_rcu(tb, node, head, tb_hlist) {
+ struct trie *t = (struct trie *) tb->tb_data;
+ struct trie_stat stat;
+
+ if (!t)
+ continue;
+
+ fib_table_print(seq, tb);
+
+ trie_collect_stats(t, &stat);
+ trie_show_stats(seq, &stat);
+#ifdef CONFIG_IP_FIB_TRIE_STATS
+ trie_show_usage(seq, &t->stats);
+#endif
+ }
+ }
+
+ return 0;
+}
+
+static int fib_triestat_seq_open(struct inode *inode, struct file *file)
+{
+ return single_open_net(inode, file, fib_triestat_seq_show);
+}
+
+static const struct file_operations fib_triestat_fops = {
+ .owner = THIS_MODULE,
+ .open = fib_triestat_seq_open,
+ .read = seq_read,
+ .llseek = seq_lseek,
+ .release = single_release_net,
+};
+
+static struct rt_trie_node *fib_trie_get_idx(struct seq_file *seq, loff_t pos)
+{
+ struct fib_trie_iter *iter = seq->private;
+ struct net *net = seq_file_net(seq);
+ loff_t idx = 0;
+ unsigned int h;
+
+ for (h = 0; h < FIB_TABLE_HASHSZ; h++) {
+ struct hlist_head *head = &net->ipv4.fib_table_hash[h];
+ struct hlist_node *node;
+ struct fib_table *tb;
+
+ hlist_for_each_entry_rcu(tb, node, head, tb_hlist) {
+ struct rt_trie_node *n;
+
+ for (n = fib_trie_get_first(iter,
+ (struct trie *) tb->tb_data);
+ n; n = fib_trie_get_next(iter))
+ if (pos == idx++) {
+ iter->tb = tb;
+ return n;
+ }
+ }
+ }
+
+ return NULL;
+}
+
+static void *fib_trie_seq_start(struct seq_file *seq, loff_t *pos)
+ __acquires(RCU)
+{
+ rcu_read_lock();
+ return fib_trie_get_idx(seq, *pos);
+}
+
+static void *fib_trie_seq_next(struct seq_file *seq, void *v, loff_t *pos)
+{
+ struct fib_trie_iter *iter = seq->private;
+ struct net *net = seq_file_net(seq);
+ struct fib_table *tb = iter->tb;
+ struct hlist_node *tb_node;
+ unsigned int h;
+ struct rt_trie_node *n;
+
+ ++*pos;
+ /* next node in same table */
+ n = fib_trie_get_next(iter);
+ if (n)
+ return n;
+
+ /* walk rest of this hash chain */
+ h = tb->tb_id & (FIB_TABLE_HASHSZ - 1);
+ while ((tb_node = rcu_dereference(hlist_next_rcu(&tb->tb_hlist)))) {
+ tb = hlist_entry(tb_node, struct fib_table, tb_hlist);
+ n = fib_trie_get_first(iter, (struct trie *) tb->tb_data);
+ if (n)
+ goto found;
+ }
+
+ /* new hash chain */
+ while (++h < FIB_TABLE_HASHSZ) {
+ struct hlist_head *head = &net->ipv4.fib_table_hash[h];
+ hlist_for_each_entry_rcu(tb, tb_node, head, tb_hlist) {
+ n = fib_trie_get_first(iter, (struct trie *) tb->tb_data);
+ if (n)
+ goto found;
+ }
+ }
+ return NULL;
+
+found:
+ iter->tb = tb;
+ return n;
+}
+
+static void fib_trie_seq_stop(struct seq_file *seq, void *v)
+ __releases(RCU)
+{
+ rcu_read_unlock();
+}
+
+static void seq_indent(struct seq_file *seq, int n)
+{
+ while (n-- > 0)
+ seq_puts(seq, " ");
+}
+
+static inline const char *rtn_scope(char *buf, size_t len, enum rt_scope_t s)
+{
+ switch (s) {
+ case RT_SCOPE_UNIVERSE: return "universe";
+ case RT_SCOPE_SITE: return "site";
+ case RT_SCOPE_LINK: return "link";
+ case RT_SCOPE_HOST: return "host";
+ case RT_SCOPE_NOWHERE: return "nowhere";
+ default:
+ snprintf(buf, len, "scope=%d", s);
+ return buf;
+ }
+}
+
+static const char *const rtn_type_names[__RTN_MAX] = {
+ [RTN_UNSPEC] = "UNSPEC",
+ [RTN_UNICAST] = "UNICAST",
+ [RTN_LOCAL] = "LOCAL",
+ [RTN_BROADCAST] = "BROADCAST",
+ [RTN_ANYCAST] = "ANYCAST",
+ [RTN_MULTICAST] = "MULTICAST",
+ [RTN_BLACKHOLE] = "BLACKHOLE",
+ [RTN_UNREACHABLE] = "UNREACHABLE",
+ [RTN_PROHIBIT] = "PROHIBIT",
+ [RTN_THROW] = "THROW",
+ [RTN_NAT] = "NAT",
+ [RTN_XRESOLVE] = "XRESOLVE",
+};
+
+static inline const char *rtn_type(char *buf, size_t len, unsigned int t)
+{
+ if (t < __RTN_MAX && rtn_type_names[t])
+ return rtn_type_names[t];
+ snprintf(buf, len, "type %u", t);
+ return buf;
+}
+
+/* Pretty print the trie */
+static int fib_trie_seq_show(struct seq_file *seq, void *v)
+{
+ const struct fib_trie_iter *iter = seq->private;
+ struct rt_trie_node *n = v;
+
+ if (!node_parent_rcu(n))
+ fib_table_print(seq, iter->tb);
+
+ if (IS_TNODE(n)) {
+ struct tnode *tn = (struct tnode *) n;
+ __be32 prf = htonl(mask_pfx(tn->key, tn->pos));
+
+ seq_indent(seq, iter->depth-1);
+ seq_printf(seq, " +-- %pI4/%d %d %d %d\n",
+ &prf, tn->pos, tn->bits, tn->full_children,
+ tn->empty_children);
+
+ } else {
+ struct leaf *l = (struct leaf *) n;
+ struct leaf_info *li;
+ struct hlist_node *node;
+ __be32 val = htonl(l->key);
+
+ seq_indent(seq, iter->depth);
+ seq_printf(seq, " |-- %pI4\n", &val);
+
+ hlist_for_each_entry_rcu(li, node, &l->list, hlist) {
+ struct fib_alias *fa;
+
+ list_for_each_entry_rcu(fa, &li->falh, fa_list) {
+ char buf1[32], buf2[32];
+
+ seq_indent(seq, iter->depth+1);
+ seq_printf(seq, " /%d %s %s", li->plen,
+ rtn_scope(buf1, sizeof(buf1),
+ fa->fa_info->fib_scope),
+ rtn_type(buf2, sizeof(buf2),
+ fa->fa_type));
+ if (fa->fa_tos)
+ seq_printf(seq, " tos=%d", fa->fa_tos);
+ seq_putc(seq, '\n');
+ }
+ }
+ }
+
+ return 0;
+}
+
+static const 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)
+{
+ return seq_open_net(inode, file, &fib_trie_seq_ops,
+ sizeof(struct fib_trie_iter));
+}
+
+static const struct file_operations fib_trie_fops = {
+ .owner = THIS_MODULE,
+ .open = fib_trie_seq_open,
+ .read = seq_read,
+ .llseek = seq_lseek,
+ .release = seq_release_net,
+};
+
+struct fib_route_iter {
+ struct seq_net_private p;
+ struct trie *main_trie;
+ loff_t pos;
+ t_key key;
+};
+
+static struct leaf *fib_route_get_idx(struct fib_route_iter *iter, loff_t pos)
+{
+ struct leaf *l = NULL;
+ struct trie *t = iter->main_trie;
+
+ /* use cache location of last found key */
+ if (iter->pos > 0 && pos >= iter->pos && (l = fib_find_node(t, iter->key)))
+ pos -= iter->pos;
+ else {
+ iter->pos = 0;
+ l = trie_firstleaf(t);
+ }
+
+ while (l && pos-- > 0) {
+ iter->pos++;
+ l = trie_nextleaf(l);
+ }
+
+ if (l)
+ iter->key = pos; /* remember it */
+ else
+ iter->pos = 0; /* forget it */
+
+ return l;
+}
+
+static void *fib_route_seq_start(struct seq_file *seq, loff_t *pos)
+ __acquires(RCU)
+{
+ struct fib_route_iter *iter = seq->private;
+ struct fib_table *tb;
+
+ rcu_read_lock();
+ tb = fib_get_table(seq_file_net(seq), RT_TABLE_MAIN);
+ if (!tb)
+ return NULL;
+
+ iter->main_trie = (struct trie *) tb->tb_data;
+ if (*pos == 0)
+ return SEQ_START_TOKEN;
+ else
+ return fib_route_get_idx(iter, *pos - 1);
+}
+
+static void *fib_route_seq_next(struct seq_file *seq, void *v, loff_t *pos)
+{
+ struct fib_route_iter *iter = seq->private;
+ struct leaf *l = v;
+
+ ++*pos;
+ if (v == SEQ_START_TOKEN) {
+ iter->pos = 0;
+ l = trie_firstleaf(iter->main_trie);
+ } else {
+ iter->pos++;
+ l = trie_nextleaf(l);
+ }
+
+ if (l)
+ iter->key = l->key;
+ else
+ iter->pos = 0;
+ return l;
+}
+
+static void fib_route_seq_stop(struct seq_file *seq, void *v)
+ __releases(RCU)
+{
+ rcu_read_unlock();
+}
+
+static unsigned int fib_flag_trans(int type, __be32 mask, const struct fib_info *fi)
+{
+ unsigned int flags = 0;
+
+ if (type == RTN_UNREACHABLE || type == RTN_PROHIBIT)
+ flags = RTF_REJECT;
+ if (fi && fi->fib_nh->nh_gw)
+ flags |= RTF_GATEWAY;
+ if (mask == htonl(0xFFFFFFFF))
+ flags |= RTF_HOST;
+ flags |= RTF_UP;
+ return flags;
+}
+
+/*
+ * This outputs /proc/net/route.
+ * The format of the file is not supposed to be changed
+ * and needs to be same as fib_hash output to avoid breaking
+ * legacy utilities
+ */
+static int fib_route_seq_show(struct seq_file *seq, void *v)
+{
+ struct leaf *l = v;
+ struct leaf_info *li;
+ struct hlist_node *node;
+
+ if (v == SEQ_START_TOKEN) {
+ seq_printf(seq, "%-127s\n", "Iface\tDestination\tGateway "
+ "\tFlags\tRefCnt\tUse\tMetric\tMask\t\tMTU"
+ "\tWindow\tIRTT");
+ return 0;
+ }
+
+ hlist_for_each_entry_rcu(li, node, &l->list, hlist) {
+ struct fib_alias *fa;
+ __be32 mask, prefix;
+
+ mask = inet_make_mask(li->plen);
+ prefix = htonl(l->key);
+
+ list_for_each_entry_rcu(fa, &li->falh, fa_list) {
+ const struct fib_info *fi = fa->fa_info;
+ unsigned int flags = fib_flag_trans(fa->fa_type, mask, fi);
+ int len;
+
+ if (fa->fa_type == RTN_BROADCAST
+ || fa->fa_type == RTN_MULTICAST)
+ continue;
+
+ if (fi)
+ seq_printf(seq,
+ "%s\t%08X\t%08X\t%04X\t%d\t%u\t"
+ "%d\t%08X\t%d\t%u\t%u%n",
+ fi->fib_dev ? fi->fib_dev->name : "*",
+ prefix,
+ fi->fib_nh->nh_gw, flags, 0, 0,
+ fi->fib_priority,
+ mask,
+ (fi->fib_advmss ?
+ fi->fib_advmss + 40 : 0),
+ fi->fib_window,
+ fi->fib_rtt >> 3, &len);
+ else
+ seq_printf(seq,
+ "*\t%08X\t%08X\t%04X\t%d\t%u\t"
+ "%d\t%08X\t%d\t%u\t%u%n",
+ prefix, 0, flags, 0, 0, 0,
+ mask, 0, 0, 0, &len);
+
+ seq_printf(seq, "%*s\n", 127 - len, "");
+ }
+ }
+
+ return 0;
+}
+
+static const struct seq_operations fib_route_seq_ops = {
+ .start = fib_route_seq_start,
+ .next = fib_route_seq_next,
+ .stop = fib_route_seq_stop,
+ .show = fib_route_seq_show,
+};
+
+static int fib_route_seq_open(struct inode *inode, struct file *file)
+{
+ return seq_open_net(inode, file, &fib_route_seq_ops,
+ sizeof(struct fib_route_iter));
+}
+
+static const struct file_operations fib_route_fops = {
+ .owner = THIS_MODULE,
+ .open = fib_route_seq_open,
+ .read = seq_read,
+ .llseek = seq_lseek,
+ .release = seq_release_net,
+};
+
+int __net_init fib_proc_init(struct net *net)
+{
+ if (!proc_net_fops_create(net, "fib_trie", S_IRUGO, &fib_trie_fops))
+ goto out1;
+
+ if (!proc_net_fops_create(net, "fib_triestat", S_IRUGO,
+ &fib_triestat_fops))
+ goto out2;
+
+ if (!proc_net_fops_create(net, "route", S_IRUGO, &fib_route_fops))
+ goto out3;
+
+ return 0;
+
+out3:
+ proc_net_remove(net, "fib_triestat");
+out2:
+ proc_net_remove(net, "fib_trie");
+out1:
+ return -ENOMEM;
+}
+
+void __net_exit fib_proc_exit(struct net *net)
+{
+ proc_net_remove(net, "fib_trie");
+ proc_net_remove(net, "fib_triestat");
+ proc_net_remove(net, "route");
+}
+
+#endif /* CONFIG_PROC_FS */