2 * Linux INET6 implementation
3 * Forwarding Information Database
6 * Pedro Roque <roque@di.fc.ul.pt>
8 * This program is free software; you can redistribute it and/or
9 * modify it under the terms of the GNU General Public License
10 * as published by the Free Software Foundation; either version
11 * 2 of the License, or (at your option) any later version.
14 * Yuji SEKIYA @USAGI: Support default route on router node;
15 * remove ip6_null_entry from the top of
17 * Ville Nuorvala: Fixed routing subtrees.
20 #define pr_fmt(fmt) "IPv6: " fmt
22 #include <linux/errno.h>
23 #include <linux/types.h>
24 #include <linux/net.h>
25 #include <linux/route.h>
26 #include <linux/netdevice.h>
27 #include <linux/in6.h>
28 #include <linux/init.h>
29 #include <linux/list.h>
30 #include <linux/slab.h>
33 #include <net/ndisc.h>
34 #include <net/addrconf.h>
35 #include <net/lwtunnel.h>
36 #include <net/fib_notifier.h>
38 #include <net/ip6_fib.h>
39 #include <net/ip6_route.h>
41 static struct kmem_cache *fib6_node_kmem __read_mostly;
46 int (*func)(struct rt6_info *, void *arg);
51 #ifdef CONFIG_IPV6_SUBTREES
52 #define FWS_INIT FWS_S
54 #define FWS_INIT FWS_L
57 static struct rt6_info *fib6_find_prefix(struct net *net,
58 struct fib6_table *table,
59 struct fib6_node *fn);
60 static struct fib6_node *fib6_repair_tree(struct net *net,
61 struct fib6_table *table,
62 struct fib6_node *fn);
63 static int fib6_walk(struct net *net, struct fib6_walker *w);
64 static int fib6_walk_continue(struct fib6_walker *w);
67 * A routing update causes an increase of the serial number on the
68 * affected subtree. This allows for cached routes to be asynchronously
69 * tested when modifications are made to the destination cache as a
70 * result of redirects, path MTU changes, etc.
73 static void fib6_gc_timer_cb(unsigned long arg);
75 #define FOR_WALKERS(net, w) \
76 list_for_each_entry(w, &(net)->ipv6.fib6_walkers, lh)
78 static void fib6_walker_link(struct net *net, struct fib6_walker *w)
80 write_lock_bh(&net->ipv6.fib6_walker_lock);
81 list_add(&w->lh, &net->ipv6.fib6_walkers);
82 write_unlock_bh(&net->ipv6.fib6_walker_lock);
85 static void fib6_walker_unlink(struct net *net, struct fib6_walker *w)
87 write_lock_bh(&net->ipv6.fib6_walker_lock);
89 write_unlock_bh(&net->ipv6.fib6_walker_lock);
92 static int fib6_new_sernum(struct net *net)
97 old = atomic_read(&net->ipv6.fib6_sernum);
98 new = old < INT_MAX ? old + 1 : 1;
99 } while (atomic_cmpxchg(&net->ipv6.fib6_sernum,
105 FIB6_NO_SERNUM_CHANGE = 0,
108 void fib6_update_sernum(struct rt6_info *rt)
110 struct fib6_table *table = rt->rt6i_table;
111 struct net *net = dev_net(rt->dst.dev);
112 struct fib6_node *fn;
114 spin_lock_bh(&table->tb6_lock);
115 fn = rcu_dereference_protected(rt->rt6i_node,
116 lockdep_is_held(&table->tb6_lock));
118 fn->fn_sernum = fib6_new_sernum(net);
119 spin_unlock_bh(&table->tb6_lock);
123 * Auxiliary address test functions for the radix tree.
125 * These assume a 32bit processor (although it will work on
132 #if defined(__LITTLE_ENDIAN)
133 # define BITOP_BE32_SWIZZLE (0x1F & ~7)
135 # define BITOP_BE32_SWIZZLE 0
138 static __be32 addr_bit_set(const void *token, int fn_bit)
140 const __be32 *addr = token;
143 * 1 << ((~fn_bit ^ BITOP_BE32_SWIZZLE) & 0x1f)
144 * is optimized version of
145 * htonl(1 << ((~fn_bit)&0x1F))
146 * See include/asm-generic/bitops/le.h.
148 return (__force __be32)(1 << ((~fn_bit ^ BITOP_BE32_SWIZZLE) & 0x1f)) &
152 static struct fib6_node *node_alloc(struct net *net)
154 struct fib6_node *fn;
156 fn = kmem_cache_zalloc(fib6_node_kmem, GFP_ATOMIC);
158 net->ipv6.rt6_stats->fib_nodes++;
163 static void node_free_immediate(struct net *net, struct fib6_node *fn)
165 kmem_cache_free(fib6_node_kmem, fn);
166 net->ipv6.rt6_stats->fib_nodes--;
169 static void node_free_rcu(struct rcu_head *head)
171 struct fib6_node *fn = container_of(head, struct fib6_node, rcu);
173 kmem_cache_free(fib6_node_kmem, fn);
176 static void node_free(struct net *net, struct fib6_node *fn)
178 call_rcu(&fn->rcu, node_free_rcu);
179 net->ipv6.rt6_stats->fib_nodes--;
182 void rt6_free_pcpu(struct rt6_info *non_pcpu_rt)
186 if (!non_pcpu_rt->rt6i_pcpu)
189 for_each_possible_cpu(cpu) {
190 struct rt6_info **ppcpu_rt;
191 struct rt6_info *pcpu_rt;
193 ppcpu_rt = per_cpu_ptr(non_pcpu_rt->rt6i_pcpu, cpu);
196 dst_dev_put(&pcpu_rt->dst);
197 dst_release(&pcpu_rt->dst);
202 EXPORT_SYMBOL_GPL(rt6_free_pcpu);
204 static void fib6_free_table(struct fib6_table *table)
206 inetpeer_invalidate_tree(&table->tb6_peers);
210 static void fib6_link_table(struct net *net, struct fib6_table *tb)
215 * Initialize table lock at a single place to give lockdep a key,
216 * tables aren't visible prior to being linked to the list.
218 spin_lock_init(&tb->tb6_lock);
219 h = tb->tb6_id & (FIB6_TABLE_HASHSZ - 1);
222 * No protection necessary, this is the only list mutatation
223 * operation, tables never disappear once they exist.
225 hlist_add_head_rcu(&tb->tb6_hlist, &net->ipv6.fib_table_hash[h]);
228 #ifdef CONFIG_IPV6_MULTIPLE_TABLES
230 static struct fib6_table *fib6_alloc_table(struct net *net, u32 id)
232 struct fib6_table *table;
234 table = kzalloc(sizeof(*table), GFP_ATOMIC);
237 rcu_assign_pointer(table->tb6_root.leaf,
238 net->ipv6.ip6_null_entry);
239 table->tb6_root.fn_flags = RTN_ROOT | RTN_TL_ROOT | RTN_RTINFO;
240 inet_peer_base_init(&table->tb6_peers);
246 struct fib6_table *fib6_new_table(struct net *net, u32 id)
248 struct fib6_table *tb;
252 tb = fib6_get_table(net, id);
256 tb = fib6_alloc_table(net, id);
258 fib6_link_table(net, tb);
262 EXPORT_SYMBOL_GPL(fib6_new_table);
264 struct fib6_table *fib6_get_table(struct net *net, u32 id)
266 struct fib6_table *tb;
267 struct hlist_head *head;
272 h = id & (FIB6_TABLE_HASHSZ - 1);
274 head = &net->ipv6.fib_table_hash[h];
275 hlist_for_each_entry_rcu(tb, head, tb6_hlist) {
276 if (tb->tb6_id == id) {
285 EXPORT_SYMBOL_GPL(fib6_get_table);
287 static void __net_init fib6_tables_init(struct net *net)
289 fib6_link_table(net, net->ipv6.fib6_main_tbl);
290 fib6_link_table(net, net->ipv6.fib6_local_tbl);
294 struct fib6_table *fib6_new_table(struct net *net, u32 id)
296 return fib6_get_table(net, id);
299 struct fib6_table *fib6_get_table(struct net *net, u32 id)
301 return net->ipv6.fib6_main_tbl;
304 struct dst_entry *fib6_rule_lookup(struct net *net, struct flowi6 *fl6,
305 int flags, pol_lookup_t lookup)
309 rt = lookup(net, net->ipv6.fib6_main_tbl, fl6, flags);
310 if (rt->dst.error == -EAGAIN) {
312 rt = net->ipv6.ip6_null_entry;
319 static void __net_init fib6_tables_init(struct net *net)
321 fib6_link_table(net, net->ipv6.fib6_main_tbl);
326 unsigned int fib6_tables_seq_read(struct net *net)
328 unsigned int h, fib_seq = 0;
331 for (h = 0; h < FIB6_TABLE_HASHSZ; h++) {
332 struct hlist_head *head = &net->ipv6.fib_table_hash[h];
333 struct fib6_table *tb;
335 hlist_for_each_entry_rcu(tb, head, tb6_hlist)
336 fib_seq += tb->fib_seq;
343 static int call_fib6_entry_notifier(struct notifier_block *nb, struct net *net,
344 enum fib_event_type event_type,
347 struct fib6_entry_notifier_info info = {
351 return call_fib6_notifier(nb, net, event_type, &info.info);
354 static int call_fib6_entry_notifiers(struct net *net,
355 enum fib_event_type event_type,
357 struct netlink_ext_ack *extack)
359 struct fib6_entry_notifier_info info = {
360 .info.extack = extack,
364 rt->rt6i_table->fib_seq++;
365 return call_fib6_notifiers(net, event_type, &info.info);
368 struct fib6_dump_arg {
370 struct notifier_block *nb;
373 static void fib6_rt_dump(struct rt6_info *rt, struct fib6_dump_arg *arg)
375 if (rt == arg->net->ipv6.ip6_null_entry)
377 call_fib6_entry_notifier(arg->nb, arg->net, FIB_EVENT_ENTRY_ADD, rt);
380 static int fib6_node_dump(struct fib6_walker *w)
384 for_each_fib6_walker_rt(w)
385 fib6_rt_dump(rt, w->args);
390 static void fib6_table_dump(struct net *net, struct fib6_table *tb,
391 struct fib6_walker *w)
393 w->root = &tb->tb6_root;
394 spin_lock_bh(&tb->tb6_lock);
396 spin_unlock_bh(&tb->tb6_lock);
399 /* Called with rcu_read_lock() */
400 int fib6_tables_dump(struct net *net, struct notifier_block *nb)
402 struct fib6_dump_arg arg;
403 struct fib6_walker *w;
406 w = kzalloc(sizeof(*w), GFP_ATOMIC);
410 w->func = fib6_node_dump;
415 for (h = 0; h < FIB6_TABLE_HASHSZ; h++) {
416 struct hlist_head *head = &net->ipv6.fib_table_hash[h];
417 struct fib6_table *tb;
419 hlist_for_each_entry_rcu(tb, head, tb6_hlist)
420 fib6_table_dump(net, tb, w);
428 static int fib6_dump_node(struct fib6_walker *w)
433 for_each_fib6_walker_rt(w) {
434 res = rt6_dump_route(rt, w->args);
436 /* Frame is full, suspend walking */
441 /* Multipath routes are dumped in one route with the
442 * RTA_MULTIPATH attribute. Jump 'rt' to point to the
443 * last sibling of this route (no need to dump the
444 * sibling routes again)
446 if (rt->rt6i_nsiblings)
447 rt = list_last_entry(&rt->rt6i_siblings,
455 static void fib6_dump_end(struct netlink_callback *cb)
457 struct net *net = sock_net(cb->skb->sk);
458 struct fib6_walker *w = (void *)cb->args[2];
463 fib6_walker_unlink(net, w);
468 cb->done = (void *)cb->args[3];
472 static int fib6_dump_done(struct netlink_callback *cb)
475 return cb->done ? cb->done(cb) : 0;
478 static int fib6_dump_table(struct fib6_table *table, struct sk_buff *skb,
479 struct netlink_callback *cb)
481 struct net *net = sock_net(skb->sk);
482 struct fib6_walker *w;
485 w = (void *)cb->args[2];
486 w->root = &table->tb6_root;
488 if (cb->args[4] == 0) {
492 spin_lock_bh(&table->tb6_lock);
493 res = fib6_walk(net, w);
494 spin_unlock_bh(&table->tb6_lock);
497 cb->args[5] = w->root->fn_sernum;
500 if (cb->args[5] != w->root->fn_sernum) {
501 /* Begin at the root if the tree changed */
502 cb->args[5] = w->root->fn_sernum;
509 spin_lock_bh(&table->tb6_lock);
510 res = fib6_walk_continue(w);
511 spin_unlock_bh(&table->tb6_lock);
513 fib6_walker_unlink(net, w);
521 static int inet6_dump_fib(struct sk_buff *skb, struct netlink_callback *cb)
523 struct net *net = sock_net(skb->sk);
525 unsigned int e = 0, s_e;
526 struct rt6_rtnl_dump_arg arg;
527 struct fib6_walker *w;
528 struct fib6_table *tb;
529 struct hlist_head *head;
535 w = (void *)cb->args[2];
539 * 1. hook callback destructor.
541 cb->args[3] = (long)cb->done;
542 cb->done = fib6_dump_done;
545 * 2. allocate and initialize walker.
547 w = kzalloc(sizeof(*w), GFP_ATOMIC);
550 w->func = fib6_dump_node;
551 cb->args[2] = (long)w;
560 for (h = s_h; h < FIB6_TABLE_HASHSZ; h++, s_e = 0) {
562 head = &net->ipv6.fib_table_hash[h];
563 hlist_for_each_entry_rcu(tb, head, tb6_hlist) {
566 res = fib6_dump_table(tb, skb, cb);
578 res = res < 0 ? res : skb->len;
587 * return the appropriate node for a routing tree "add" operation
588 * by either creating and inserting or by returning an existing
592 static struct fib6_node *fib6_add_1(struct net *net,
593 struct fib6_table *table,
594 struct fib6_node *root,
595 struct in6_addr *addr, int plen,
596 int offset, int allow_create,
597 int replace_required,
598 struct netlink_ext_ack *extack)
600 struct fib6_node *fn, *in, *ln;
601 struct fib6_node *pn = NULL;
606 RT6_TRACE("fib6_add_1\n");
608 /* insert node in tree */
613 struct rt6_info *leaf = rcu_dereference_protected(fn->leaf,
614 lockdep_is_held(&table->tb6_lock));
615 key = (struct rt6key *)((u8 *)leaf + offset);
620 if (plen < fn->fn_bit ||
621 !ipv6_prefix_equal(&key->addr, addr, fn->fn_bit)) {
623 if (replace_required) {
624 NL_SET_ERR_MSG(extack,
625 "Can not replace route - no match found");
626 pr_warn("Can't replace route, no match found\n");
627 return ERR_PTR(-ENOENT);
629 pr_warn("NLM_F_CREATE should be set when creating new route\n");
638 if (plen == fn->fn_bit) {
639 /* clean up an intermediate node */
640 if (!(fn->fn_flags & RTN_RTINFO)) {
641 RCU_INIT_POINTER(fn->leaf, NULL);
649 * We have more bits to go
652 /* Try to walk down on tree. */
653 dir = addr_bit_set(addr, fn->fn_bit);
656 rcu_dereference_protected(fn->right,
657 lockdep_is_held(&table->tb6_lock)) :
658 rcu_dereference_protected(fn->left,
659 lockdep_is_held(&table->tb6_lock));
663 /* We should not create new node because
664 * NLM_F_REPLACE was specified without NLM_F_CREATE
665 * I assume it is safe to require NLM_F_CREATE when
666 * REPLACE flag is used! Later we may want to remove the
667 * check for replace_required, because according
668 * to netlink specification, NLM_F_CREATE
669 * MUST be specified if new route is created.
670 * That would keep IPv6 consistent with IPv4
672 if (replace_required) {
673 NL_SET_ERR_MSG(extack,
674 "Can not replace route - no match found");
675 pr_warn("Can't replace route, no match found\n");
676 return ERR_PTR(-ENOENT);
678 pr_warn("NLM_F_CREATE should be set when creating new route\n");
681 * We walked to the bottom of tree.
682 * Create new leaf node without children.
685 ln = node_alloc(net);
688 return ERR_PTR(-ENOMEM);
690 RCU_INIT_POINTER(ln->parent, pn);
693 rcu_assign_pointer(pn->right, ln);
695 rcu_assign_pointer(pn->left, ln);
702 * split since we don't have a common prefix anymore or
703 * we have a less significant route.
704 * we've to insert an intermediate node on the list
705 * this new node will point to the one we need to create
709 pn = rcu_dereference_protected(fn->parent,
710 lockdep_is_held(&table->tb6_lock));
712 /* find 1st bit in difference between the 2 addrs.
714 See comment in __ipv6_addr_diff: bit may be an invalid value,
715 but if it is >= plen, the value is ignored in any case.
718 bit = __ipv6_addr_diff(addr, &key->addr, sizeof(*addr));
723 * (new leaf node)[ln] (old node)[fn]
726 in = node_alloc(net);
727 ln = node_alloc(net);
731 node_free_immediate(net, in);
733 node_free_immediate(net, ln);
734 return ERR_PTR(-ENOMEM);
738 * new intermediate node.
740 * be off since that an address that chooses one of
741 * the branches would not match less specific routes
742 * in the other branch
747 RCU_INIT_POINTER(in->parent, pn);
749 atomic_inc(&rcu_dereference_protected(in->leaf,
750 lockdep_is_held(&table->tb6_lock))->rt6i_ref);
752 /* update parent pointer */
754 rcu_assign_pointer(pn->right, in);
756 rcu_assign_pointer(pn->left, in);
760 RCU_INIT_POINTER(ln->parent, in);
761 rcu_assign_pointer(fn->parent, in);
763 if (addr_bit_set(addr, bit)) {
764 rcu_assign_pointer(in->right, ln);
765 rcu_assign_pointer(in->left, fn);
767 rcu_assign_pointer(in->left, ln);
768 rcu_assign_pointer(in->right, fn);
770 } else { /* plen <= bit */
773 * (new leaf node)[ln]
775 * (old node)[fn] NULL
778 ln = node_alloc(net);
781 return ERR_PTR(-ENOMEM);
785 RCU_INIT_POINTER(ln->parent, pn);
787 if (addr_bit_set(&key->addr, plen))
788 RCU_INIT_POINTER(ln->right, fn);
790 RCU_INIT_POINTER(ln->left, fn);
792 rcu_assign_pointer(fn->parent, ln);
795 rcu_assign_pointer(pn->right, ln);
797 rcu_assign_pointer(pn->left, ln);
802 static bool rt6_qualify_for_ecmp(struct rt6_info *rt)
804 return (rt->rt6i_flags & (RTF_GATEWAY|RTF_ADDRCONF|RTF_DYNAMIC)) ==
808 static void fib6_copy_metrics(u32 *mp, const struct mx6_config *mxc)
812 for (i = 0; i < RTAX_MAX; i++) {
813 if (test_bit(i, mxc->mx_valid))
818 static int fib6_commit_metrics(struct dst_entry *dst, struct mx6_config *mxc)
823 if (dst->flags & DST_HOST) {
824 u32 *mp = dst_metrics_write_ptr(dst);
829 fib6_copy_metrics(mp, mxc);
831 dst_init_metrics(dst, mxc->mx, false);
833 /* We've stolen mx now. */
840 static void fib6_purge_rt(struct rt6_info *rt, struct fib6_node *fn,
843 struct fib6_table *table = rt->rt6i_table;
845 if (atomic_read(&rt->rt6i_ref) != 1) {
846 /* This route is used as dummy address holder in some split
847 * nodes. It is not leaked, but it still holds other resources,
848 * which must be released in time. So, scan ascendant nodes
849 * and replace dummy references to this route with references
850 * to still alive ones.
853 struct rt6_info *leaf = rcu_dereference_protected(fn->leaf,
854 lockdep_is_held(&table->tb6_lock));
855 struct rt6_info *new_leaf;
856 if (!(fn->fn_flags & RTN_RTINFO) && leaf == rt) {
857 new_leaf = fib6_find_prefix(net, table, fn);
858 atomic_inc(&new_leaf->rt6i_ref);
859 rcu_assign_pointer(fn->leaf, new_leaf);
862 fn = rcu_dereference_protected(fn->parent,
863 lockdep_is_held(&table->tb6_lock));
869 * Insert routing information in a node.
872 static int fib6_add_rt2node(struct fib6_node *fn, struct rt6_info *rt,
873 struct nl_info *info, struct mx6_config *mxc,
874 struct netlink_ext_ack *extack)
876 struct rt6_info *leaf = rcu_dereference_protected(fn->leaf,
877 lockdep_is_held(&rt->rt6i_table->tb6_lock));
878 struct rt6_info *iter = NULL;
879 struct rt6_info __rcu **ins;
880 struct rt6_info __rcu **fallback_ins = NULL;
881 int replace = (info->nlh &&
882 (info->nlh->nlmsg_flags & NLM_F_REPLACE));
883 int add = (!info->nlh ||
884 (info->nlh->nlmsg_flags & NLM_F_CREATE));
886 bool rt_can_ecmp = rt6_qualify_for_ecmp(rt);
887 u16 nlflags = NLM_F_EXCL;
890 if (info->nlh && (info->nlh->nlmsg_flags & NLM_F_APPEND))
891 nlflags |= NLM_F_APPEND;
895 for (iter = leaf; iter;
896 iter = rcu_dereference_protected(iter->dst.rt6_next,
897 lockdep_is_held(&rt->rt6i_table->tb6_lock))) {
899 * Search for duplicates
902 if (iter->rt6i_metric == rt->rt6i_metric) {
904 * Same priority level
907 (info->nlh->nlmsg_flags & NLM_F_EXCL))
910 nlflags &= ~NLM_F_EXCL;
912 if (rt_can_ecmp == rt6_qualify_for_ecmp(iter)) {
917 fallback_ins = fallback_ins ?: ins;
921 if (rt6_duplicate_nexthop(iter, rt)) {
922 if (rt->rt6i_nsiblings)
923 rt->rt6i_nsiblings = 0;
924 if (!(iter->rt6i_flags & RTF_EXPIRES))
926 if (!(rt->rt6i_flags & RTF_EXPIRES))
927 rt6_clean_expires(iter);
929 rt6_set_expires(iter, rt->dst.expires);
930 iter->rt6i_pmtu = rt->rt6i_pmtu;
933 /* If we have the same destination and the same metric,
934 * but not the same gateway, then the route we try to
935 * add is sibling to this route, increment our counter
936 * of siblings, and later we will add our route to the
938 * Only static routes (which don't have flag
939 * RTF_EXPIRES) are used for ECMPv6.
941 * To avoid long list, we only had siblings if the
942 * route have a gateway.
945 rt6_qualify_for_ecmp(iter))
946 rt->rt6i_nsiblings++;
949 if (iter->rt6i_metric > rt->rt6i_metric)
953 ins = &iter->dst.rt6_next;
956 if (fallback_ins && !found) {
957 /* No ECMP-able route found, replace first non-ECMP one */
959 iter = rcu_dereference_protected(*ins,
960 lockdep_is_held(&rt->rt6i_table->tb6_lock));
964 /* Reset round-robin state, if necessary */
965 if (ins == &fn->leaf)
968 /* Link this route to others same route. */
969 if (rt->rt6i_nsiblings) {
970 unsigned int rt6i_nsiblings;
971 struct rt6_info *sibling, *temp_sibling;
973 /* Find the first route that have the same metric */
976 if (sibling->rt6i_metric == rt->rt6i_metric &&
977 rt6_qualify_for_ecmp(sibling)) {
978 list_add_tail(&rt->rt6i_siblings,
979 &sibling->rt6i_siblings);
982 sibling = rcu_dereference_protected(sibling->dst.rt6_next,
983 lockdep_is_held(&rt->rt6i_table->tb6_lock));
985 /* For each sibling in the list, increment the counter of
986 * siblings. BUG() if counters does not match, list of siblings
990 list_for_each_entry_safe(sibling, temp_sibling,
991 &rt->rt6i_siblings, rt6i_siblings) {
992 sibling->rt6i_nsiblings++;
993 BUG_ON(sibling->rt6i_nsiblings != rt->rt6i_nsiblings);
996 BUG_ON(rt6i_nsiblings != rt->rt6i_nsiblings);
1004 pr_warn("NLM_F_CREATE should be set when creating new route\n");
1007 nlflags |= NLM_F_CREATE;
1008 err = fib6_commit_metrics(&rt->dst, mxc);
1012 rcu_assign_pointer(rt->dst.rt6_next, iter);
1013 atomic_inc(&rt->rt6i_ref);
1014 rcu_assign_pointer(rt->rt6i_node, fn);
1015 rcu_assign_pointer(*ins, rt);
1016 call_fib6_entry_notifiers(info->nl_net, FIB_EVENT_ENTRY_ADD,
1018 if (!info->skip_notify)
1019 inet6_rt_notify(RTM_NEWROUTE, rt, info, nlflags);
1020 info->nl_net->ipv6.rt6_stats->fib_rt_entries++;
1022 if (!(fn->fn_flags & RTN_RTINFO)) {
1023 info->nl_net->ipv6.rt6_stats->fib_route_nodes++;
1024 fn->fn_flags |= RTN_RTINFO;
1033 pr_warn("NLM_F_REPLACE set, but no existing node found!\n");
1037 err = fib6_commit_metrics(&rt->dst, mxc);
1041 atomic_inc(&rt->rt6i_ref);
1042 rcu_assign_pointer(rt->rt6i_node, fn);
1043 rt->dst.rt6_next = iter->dst.rt6_next;
1044 rcu_assign_pointer(*ins, rt);
1045 call_fib6_entry_notifiers(info->nl_net, FIB_EVENT_ENTRY_REPLACE,
1047 if (!info->skip_notify)
1048 inet6_rt_notify(RTM_NEWROUTE, rt, info, NLM_F_REPLACE);
1049 if (!(fn->fn_flags & RTN_RTINFO)) {
1050 info->nl_net->ipv6.rt6_stats->fib_route_nodes++;
1051 fn->fn_flags |= RTN_RTINFO;
1053 nsiblings = iter->rt6i_nsiblings;
1054 iter->rt6i_node = NULL;
1055 fib6_purge_rt(iter, fn, info->nl_net);
1056 if (rcu_access_pointer(fn->rr_ptr) == iter)
1061 /* Replacing an ECMP route, remove all siblings */
1062 ins = &rt->dst.rt6_next;
1063 iter = rcu_dereference_protected(*ins,
1064 lockdep_is_held(&rt->rt6i_table->tb6_lock));
1066 if (iter->rt6i_metric > rt->rt6i_metric)
1068 if (rt6_qualify_for_ecmp(iter)) {
1069 *ins = iter->dst.rt6_next;
1070 iter->rt6i_node = NULL;
1071 fib6_purge_rt(iter, fn, info->nl_net);
1072 if (rcu_access_pointer(fn->rr_ptr) == iter)
1076 info->nl_net->ipv6.rt6_stats->fib_rt_entries--;
1078 ins = &iter->dst.rt6_next;
1080 iter = rcu_dereference_protected(*ins,
1081 lockdep_is_held(&rt->rt6i_table->tb6_lock));
1083 WARN_ON(nsiblings != 0);
1090 static void fib6_start_gc(struct net *net, struct rt6_info *rt)
1092 if (!timer_pending(&net->ipv6.ip6_fib_timer) &&
1093 (rt->rt6i_flags & (RTF_EXPIRES | RTF_CACHE)))
1094 mod_timer(&net->ipv6.ip6_fib_timer,
1095 jiffies + net->ipv6.sysctl.ip6_rt_gc_interval);
1098 void fib6_force_start_gc(struct net *net)
1100 if (!timer_pending(&net->ipv6.ip6_fib_timer))
1101 mod_timer(&net->ipv6.ip6_fib_timer,
1102 jiffies + net->ipv6.sysctl.ip6_rt_gc_interval);
1105 static void fib6_update_sernum_upto_root(struct rt6_info *rt,
1108 struct fib6_node *fn = rcu_dereference_protected(rt->rt6i_node,
1109 lockdep_is_held(&rt->rt6i_table->tb6_lock));
1111 /* paired with smp_rmb() in rt6_get_cookie_safe() */
1114 fn->fn_sernum = sernum;
1115 fn = rcu_dereference_protected(fn->parent,
1116 lockdep_is_held(&rt->rt6i_table->tb6_lock));
1121 * Add routing information to the routing tree.
1122 * <destination addr>/<source addr>
1123 * with source addr info in sub-trees
1124 * Need to own table->tb6_lock
1127 int fib6_add(struct fib6_node *root, struct rt6_info *rt,
1128 struct nl_info *info, struct mx6_config *mxc,
1129 struct netlink_ext_ack *extack)
1131 struct fib6_table *table = rt->rt6i_table;
1132 struct fib6_node *fn, *pn = NULL;
1134 int allow_create = 1;
1135 int replace_required = 0;
1136 int sernum = fib6_new_sernum(info->nl_net);
1138 if (WARN_ON_ONCE(!atomic_read(&rt->dst.__refcnt)))
1140 if (WARN_ON_ONCE(rt->rt6i_flags & RTF_CACHE))
1144 if (!(info->nlh->nlmsg_flags & NLM_F_CREATE))
1146 if (info->nlh->nlmsg_flags & NLM_F_REPLACE)
1147 replace_required = 1;
1149 if (!allow_create && !replace_required)
1150 pr_warn("RTM_NEWROUTE with no NLM_F_CREATE or NLM_F_REPLACE\n");
1152 fn = fib6_add_1(info->nl_net, table, root,
1153 &rt->rt6i_dst.addr, rt->rt6i_dst.plen,
1154 offsetof(struct rt6_info, rt6i_dst), allow_create,
1155 replace_required, extack);
1164 #ifdef CONFIG_IPV6_SUBTREES
1165 if (rt->rt6i_src.plen) {
1166 struct fib6_node *sn;
1168 if (!rcu_access_pointer(fn->subtree)) {
1169 struct fib6_node *sfn;
1181 /* Create subtree root node */
1182 sfn = node_alloc(info->nl_net);
1186 atomic_inc(&info->nl_net->ipv6.ip6_null_entry->rt6i_ref);
1187 rcu_assign_pointer(sfn->leaf,
1188 info->nl_net->ipv6.ip6_null_entry);
1189 sfn->fn_flags = RTN_ROOT;
1191 /* Now add the first leaf node to new subtree */
1193 sn = fib6_add_1(info->nl_net, table, sfn,
1194 &rt->rt6i_src.addr, rt->rt6i_src.plen,
1195 offsetof(struct rt6_info, rt6i_src),
1196 allow_create, replace_required, extack);
1199 /* If it is failed, discard just allocated
1200 root, and then (in failure) stale node
1203 node_free_immediate(info->nl_net, sfn);
1208 /* Now link new subtree to main tree */
1209 rcu_assign_pointer(sfn->parent, fn);
1210 rcu_assign_pointer(fn->subtree, sfn);
1212 sn = fib6_add_1(info->nl_net, table, FIB6_SUBTREE(fn),
1213 &rt->rt6i_src.addr, rt->rt6i_src.plen,
1214 offsetof(struct rt6_info, rt6i_src),
1215 allow_create, replace_required, extack);
1223 if (!rcu_access_pointer(fn->leaf)) {
1224 atomic_inc(&rt->rt6i_ref);
1225 rcu_assign_pointer(fn->leaf, rt);
1231 err = fib6_add_rt2node(fn, rt, info, mxc, extack);
1233 fib6_update_sernum_upto_root(rt, sernum);
1234 fib6_start_gc(info->nl_net, rt);
1239 #ifdef CONFIG_IPV6_SUBTREES
1241 * If fib6_add_1 has cleared the old leaf pointer in the
1242 * super-tree leaf node we have to find a new one for it.
1244 struct rt6_info *pn_leaf = rcu_dereference_protected(pn->leaf,
1245 lockdep_is_held(&table->tb6_lock));
1246 if (pn != fn && pn_leaf == rt) {
1248 RCU_INIT_POINTER(pn->leaf, NULL);
1249 atomic_dec(&rt->rt6i_ref);
1251 if (pn != fn && !pn_leaf && !(pn->fn_flags & RTN_RTINFO)) {
1252 pn_leaf = fib6_find_prefix(info->nl_net, table, pn);
1256 pn_leaf = info->nl_net->ipv6.ip6_null_entry;
1259 atomic_inc(&pn_leaf->rt6i_ref);
1260 rcu_assign_pointer(pn->leaf, pn_leaf);
1268 /* fn->leaf could be NULL if fn is an intermediate node and we
1269 * failed to add the new route to it in both subtree creation
1270 * failure and fib6_add_rt2node() failure case.
1271 * In both cases, fib6_repair_tree() should be called to fix
1274 if (fn && !(fn->fn_flags & (RTN_RTINFO|RTN_ROOT)))
1275 fib6_repair_tree(info->nl_net, table, fn);
1276 /* Always release dst as dst->__refcnt is guaranteed
1277 * to be taken before entering this function
1279 dst_release_immediate(&rt->dst);
1284 * Routing tree lookup
1288 struct lookup_args {
1289 int offset; /* key offset on rt6_info */
1290 const struct in6_addr *addr; /* search key */
1293 static struct fib6_node *fib6_lookup_1(struct fib6_node *root,
1294 struct lookup_args *args)
1296 struct fib6_node *fn;
1299 if (unlikely(args->offset == 0))
1309 struct fib6_node *next;
1311 dir = addr_bit_set(args->addr, fn->fn_bit);
1313 next = dir ? rcu_dereference(fn->right) :
1314 rcu_dereference(fn->left);
1324 struct fib6_node *subtree = FIB6_SUBTREE(fn);
1326 if (subtree || fn->fn_flags & RTN_RTINFO) {
1327 struct rt6_info *leaf = rcu_dereference(fn->leaf);
1333 key = (struct rt6key *) ((u8 *)leaf + args->offset);
1335 if (ipv6_prefix_equal(&key->addr, args->addr, key->plen)) {
1336 #ifdef CONFIG_IPV6_SUBTREES
1338 struct fib6_node *sfn;
1339 sfn = fib6_lookup_1(subtree, args + 1);
1345 if (fn->fn_flags & RTN_RTINFO)
1350 if (fn->fn_flags & RTN_ROOT)
1353 fn = rcu_dereference(fn->parent);
1359 /* called with rcu_read_lock() held
1361 struct fib6_node *fib6_lookup(struct fib6_node *root, const struct in6_addr *daddr,
1362 const struct in6_addr *saddr)
1364 struct fib6_node *fn;
1365 struct lookup_args args[] = {
1367 .offset = offsetof(struct rt6_info, rt6i_dst),
1370 #ifdef CONFIG_IPV6_SUBTREES
1372 .offset = offsetof(struct rt6_info, rt6i_src),
1377 .offset = 0, /* sentinel */
1381 fn = fib6_lookup_1(root, daddr ? args : args + 1);
1382 if (!fn || fn->fn_flags & RTN_TL_ROOT)
1389 * Get node with specified destination prefix (and source prefix,
1390 * if subtrees are used)
1391 * exact_match == true means we try to find fn with exact match of
1392 * the passed in prefix addr
1393 * exact_match == false means we try to find fn with longest prefix
1394 * match of the passed in prefix addr. This is useful for finding fn
1395 * for cached route as it will be stored in the exception table under
1396 * the node with longest prefix length.
1400 static struct fib6_node *fib6_locate_1(struct fib6_node *root,
1401 const struct in6_addr *addr,
1402 int plen, int offset,
1405 struct fib6_node *fn, *prev = NULL;
1407 for (fn = root; fn ; ) {
1408 struct rt6_info *leaf = rcu_dereference(fn->leaf);
1411 /* This node is being deleted */
1413 if (plen <= fn->fn_bit)
1419 key = (struct rt6key *)((u8 *)leaf + offset);
1424 if (plen < fn->fn_bit ||
1425 !ipv6_prefix_equal(&key->addr, addr, fn->fn_bit))
1428 if (plen == fn->fn_bit)
1435 * We have more bits to go
1437 if (addr_bit_set(addr, fn->fn_bit))
1438 fn = rcu_dereference(fn->right);
1440 fn = rcu_dereference(fn->left);
1449 struct fib6_node *fib6_locate(struct fib6_node *root,
1450 const struct in6_addr *daddr, int dst_len,
1451 const struct in6_addr *saddr, int src_len,
1454 struct fib6_node *fn;
1456 fn = fib6_locate_1(root, daddr, dst_len,
1457 offsetof(struct rt6_info, rt6i_dst),
1460 #ifdef CONFIG_IPV6_SUBTREES
1462 WARN_ON(saddr == NULL);
1464 struct fib6_node *subtree = FIB6_SUBTREE(fn);
1467 fn = fib6_locate_1(subtree, saddr, src_len,
1468 offsetof(struct rt6_info, rt6i_src),
1475 if (fn && fn->fn_flags & RTN_RTINFO)
1487 static struct rt6_info *fib6_find_prefix(struct net *net,
1488 struct fib6_table *table,
1489 struct fib6_node *fn)
1491 struct fib6_node *child_left, *child_right;
1493 if (fn->fn_flags & RTN_ROOT)
1494 return net->ipv6.ip6_null_entry;
1497 child_left = rcu_dereference_protected(fn->left,
1498 lockdep_is_held(&table->tb6_lock));
1499 child_right = rcu_dereference_protected(fn->right,
1500 lockdep_is_held(&table->tb6_lock));
1502 return rcu_dereference_protected(child_left->leaf,
1503 lockdep_is_held(&table->tb6_lock));
1505 return rcu_dereference_protected(child_right->leaf,
1506 lockdep_is_held(&table->tb6_lock));
1508 fn = FIB6_SUBTREE(fn);
1514 * Called to trim the tree of intermediate nodes when possible. "fn"
1515 * is the node we want to try and remove.
1516 * Need to own table->tb6_lock
1519 static struct fib6_node *fib6_repair_tree(struct net *net,
1520 struct fib6_table *table,
1521 struct fib6_node *fn)
1525 struct fib6_node *child;
1526 struct fib6_walker *w;
1530 struct fib6_node *fn_r = rcu_dereference_protected(fn->right,
1531 lockdep_is_held(&table->tb6_lock));
1532 struct fib6_node *fn_l = rcu_dereference_protected(fn->left,
1533 lockdep_is_held(&table->tb6_lock));
1534 struct fib6_node *pn = rcu_dereference_protected(fn->parent,
1535 lockdep_is_held(&table->tb6_lock));
1536 struct fib6_node *pn_r = rcu_dereference_protected(pn->right,
1537 lockdep_is_held(&table->tb6_lock));
1538 struct fib6_node *pn_l = rcu_dereference_protected(pn->left,
1539 lockdep_is_held(&table->tb6_lock));
1540 struct rt6_info *fn_leaf = rcu_dereference_protected(fn->leaf,
1541 lockdep_is_held(&table->tb6_lock));
1542 struct rt6_info *pn_leaf = rcu_dereference_protected(pn->leaf,
1543 lockdep_is_held(&table->tb6_lock));
1544 struct rt6_info *new_fn_leaf;
1546 RT6_TRACE("fixing tree: plen=%d iter=%d\n", fn->fn_bit, iter);
1549 WARN_ON(fn->fn_flags & RTN_RTINFO);
1550 WARN_ON(fn->fn_flags & RTN_TL_ROOT);
1556 child = fn_r, children |= 1;
1558 child = fn_l, children |= 2;
1560 if (children == 3 || FIB6_SUBTREE(fn)
1561 #ifdef CONFIG_IPV6_SUBTREES
1562 /* Subtree root (i.e. fn) may have one child */
1563 || (children && fn->fn_flags & RTN_ROOT)
1566 new_fn_leaf = fib6_find_prefix(net, table, fn);
1569 WARN_ON(!new_fn_leaf);
1570 new_fn_leaf = net->ipv6.ip6_null_entry;
1573 atomic_inc(&new_fn_leaf->rt6i_ref);
1574 rcu_assign_pointer(fn->leaf, new_fn_leaf);
1578 #ifdef CONFIG_IPV6_SUBTREES
1579 if (FIB6_SUBTREE(pn) == fn) {
1580 WARN_ON(!(fn->fn_flags & RTN_ROOT));
1581 RCU_INIT_POINTER(pn->subtree, NULL);
1584 WARN_ON(fn->fn_flags & RTN_ROOT);
1587 rcu_assign_pointer(pn->right, child);
1588 else if (pn_l == fn)
1589 rcu_assign_pointer(pn->left, child);
1595 rcu_assign_pointer(child->parent, pn);
1597 #ifdef CONFIG_IPV6_SUBTREES
1601 read_lock(&net->ipv6.fib6_walker_lock);
1602 FOR_WALKERS(net, w) {
1604 if (w->node == fn) {
1605 RT6_TRACE("W %p adjusted by delnode 1, s=%d/%d\n", w, w->state, nstate);
1610 if (w->node == fn) {
1613 RT6_TRACE("W %p adjusted by delnode 2, s=%d\n", w, w->state);
1614 w->state = w->state >= FWS_R ? FWS_U : FWS_INIT;
1616 RT6_TRACE("W %p adjusted by delnode 2, s=%d\n", w, w->state);
1617 w->state = w->state >= FWS_C ? FWS_U : FWS_INIT;
1622 read_unlock(&net->ipv6.fib6_walker_lock);
1625 if (pn->fn_flags & RTN_RTINFO || FIB6_SUBTREE(pn))
1628 RCU_INIT_POINTER(pn->leaf, NULL);
1629 rt6_release(pn_leaf);
1634 static void fib6_del_route(struct fib6_table *table, struct fib6_node *fn,
1635 struct rt6_info __rcu **rtp, struct nl_info *info)
1637 struct fib6_walker *w;
1638 struct rt6_info *rt = rcu_dereference_protected(*rtp,
1639 lockdep_is_held(&table->tb6_lock));
1640 struct net *net = info->nl_net;
1642 RT6_TRACE("fib6_del_route\n");
1644 WARN_ON_ONCE(rt->rt6i_flags & RTF_CACHE);
1647 *rtp = rt->dst.rt6_next;
1648 rt->rt6i_node = NULL;
1649 net->ipv6.rt6_stats->fib_rt_entries--;
1650 net->ipv6.rt6_stats->fib_discarded_routes++;
1652 /* Flush all cached dst in exception table */
1653 rt6_flush_exceptions(rt);
1655 /* Reset round-robin state, if necessary */
1656 if (rcu_access_pointer(fn->rr_ptr) == rt)
1659 /* Remove this entry from other siblings */
1660 if (rt->rt6i_nsiblings) {
1661 struct rt6_info *sibling, *next_sibling;
1663 list_for_each_entry_safe(sibling, next_sibling,
1664 &rt->rt6i_siblings, rt6i_siblings)
1665 sibling->rt6i_nsiblings--;
1666 rt->rt6i_nsiblings = 0;
1667 list_del_init(&rt->rt6i_siblings);
1670 /* Adjust walkers */
1671 read_lock(&net->ipv6.fib6_walker_lock);
1672 FOR_WALKERS(net, w) {
1673 if (w->state == FWS_C && w->leaf == rt) {
1674 RT6_TRACE("walker %p adjusted by delroute\n", w);
1675 w->leaf = rcu_dereference_protected(rt->dst.rt6_next,
1676 lockdep_is_held(&table->tb6_lock));
1681 read_unlock(&net->ipv6.fib6_walker_lock);
1683 /* If it was last route, expunge its radix tree node */
1684 if (!rcu_access_pointer(fn->leaf)) {
1685 fn->fn_flags &= ~RTN_RTINFO;
1686 net->ipv6.rt6_stats->fib_route_nodes--;
1687 fn = fib6_repair_tree(net, table, fn);
1690 fib6_purge_rt(rt, fn, net);
1692 call_fib6_entry_notifiers(net, FIB_EVENT_ENTRY_DEL, rt, NULL);
1693 if (!info->skip_notify)
1694 inet6_rt_notify(RTM_DELROUTE, rt, info, 0);
1698 /* Need to own table->tb6_lock */
1699 int fib6_del(struct rt6_info *rt, struct nl_info *info)
1701 struct fib6_node *fn = rcu_dereference_protected(rt->rt6i_node,
1702 lockdep_is_held(&rt->rt6i_table->tb6_lock));
1703 struct fib6_table *table = rt->rt6i_table;
1704 struct net *net = info->nl_net;
1705 struct rt6_info __rcu **rtp;
1706 struct rt6_info __rcu **rtp_next;
1709 if (rt->dst.obsolete > 0) {
1714 if (!fn || rt == net->ipv6.ip6_null_entry)
1717 WARN_ON(!(fn->fn_flags & RTN_RTINFO));
1719 /* remove cached dst from exception table */
1720 if (rt->rt6i_flags & RTF_CACHE)
1721 return rt6_remove_exception_rt(rt);
1724 * Walk the leaf entries looking for ourself
1727 for (rtp = &fn->leaf; *rtp; rtp = rtp_next) {
1728 struct rt6_info *cur = rcu_dereference_protected(*rtp,
1729 lockdep_is_held(&table->tb6_lock));
1731 fib6_del_route(table, fn, rtp, info);
1734 rtp_next = &cur->dst.rt6_next;
1740 * Tree traversal function.
1742 * Certainly, it is not interrupt safe.
1743 * However, it is internally reenterable wrt itself and fib6_add/fib6_del.
1744 * It means, that we can modify tree during walking
1745 * and use this function for garbage collection, clone pruning,
1746 * cleaning tree when a device goes down etc. etc.
1748 * It guarantees that every node will be traversed,
1749 * and that it will be traversed only once.
1751 * Callback function w->func may return:
1752 * 0 -> continue walking.
1753 * positive value -> walking is suspended (used by tree dumps,
1754 * and probably by gc, if it will be split to several slices)
1755 * negative value -> terminate walking.
1757 * The function itself returns:
1758 * 0 -> walk is complete.
1759 * >0 -> walk is incomplete (i.e. suspended)
1760 * <0 -> walk is terminated by an error.
1762 * This function is called with tb6_lock held.
1765 static int fib6_walk_continue(struct fib6_walker *w)
1767 struct fib6_node *fn, *pn, *left, *right;
1769 /* w->root should always be table->tb6_root */
1770 WARN_ON_ONCE(!(w->root->fn_flags & RTN_TL_ROOT));
1778 #ifdef CONFIG_IPV6_SUBTREES
1780 if (FIB6_SUBTREE(fn)) {
1781 w->node = FIB6_SUBTREE(fn);
1788 left = rcu_dereference_protected(fn->left, 1);
1791 w->state = FWS_INIT;
1797 right = rcu_dereference_protected(fn->right, 1);
1800 w->state = FWS_INIT;
1804 w->leaf = rcu_dereference_protected(fn->leaf, 1);
1807 if (w->leaf && fn->fn_flags & RTN_RTINFO) {
1828 pn = rcu_dereference_protected(fn->parent, 1);
1829 left = rcu_dereference_protected(pn->left, 1);
1830 right = rcu_dereference_protected(pn->right, 1);
1832 #ifdef CONFIG_IPV6_SUBTREES
1833 if (FIB6_SUBTREE(pn) == fn) {
1834 WARN_ON(!(fn->fn_flags & RTN_ROOT));
1845 w->leaf = rcu_dereference_protected(w->node->leaf, 1);
1855 static int fib6_walk(struct net *net, struct fib6_walker *w)
1859 w->state = FWS_INIT;
1862 fib6_walker_link(net, w);
1863 res = fib6_walk_continue(w);
1865 fib6_walker_unlink(net, w);
1869 static int fib6_clean_node(struct fib6_walker *w)
1872 struct rt6_info *rt;
1873 struct fib6_cleaner *c = container_of(w, struct fib6_cleaner, w);
1874 struct nl_info info = {
1878 if (c->sernum != FIB6_NO_SERNUM_CHANGE &&
1879 w->node->fn_sernum != c->sernum)
1880 w->node->fn_sernum = c->sernum;
1883 WARN_ON_ONCE(c->sernum == FIB6_NO_SERNUM_CHANGE);
1888 for_each_fib6_walker_rt(w) {
1889 res = c->func(rt, c->arg);
1892 res = fib6_del(rt, &info);
1895 pr_debug("%s: del failed: rt=%p@%p err=%d\n",
1897 rcu_access_pointer(rt->rt6i_node),
1911 * Convenient frontend to tree walker.
1913 * func is called on each route.
1914 * It may return -1 -> delete this route.
1915 * 0 -> continue walking
1918 static void fib6_clean_tree(struct net *net, struct fib6_node *root,
1919 int (*func)(struct rt6_info *, void *arg),
1920 int sernum, void *arg)
1922 struct fib6_cleaner c;
1925 c.w.func = fib6_clean_node;
1933 fib6_walk(net, &c.w);
1936 static void __fib6_clean_all(struct net *net,
1937 int (*func)(struct rt6_info *, void *),
1938 int sernum, void *arg)
1940 struct fib6_table *table;
1941 struct hlist_head *head;
1945 for (h = 0; h < FIB6_TABLE_HASHSZ; h++) {
1946 head = &net->ipv6.fib_table_hash[h];
1947 hlist_for_each_entry_rcu(table, head, tb6_hlist) {
1948 spin_lock_bh(&table->tb6_lock);
1949 fib6_clean_tree(net, &table->tb6_root,
1951 spin_unlock_bh(&table->tb6_lock);
1957 void fib6_clean_all(struct net *net, int (*func)(struct rt6_info *, void *),
1960 __fib6_clean_all(net, func, FIB6_NO_SERNUM_CHANGE, arg);
1963 static void fib6_flush_trees(struct net *net)
1965 int new_sernum = fib6_new_sernum(net);
1967 __fib6_clean_all(net, NULL, new_sernum, NULL);
1971 * Garbage collection
1974 static int fib6_age(struct rt6_info *rt, void *arg)
1976 struct fib6_gc_args *gc_args = arg;
1977 unsigned long now = jiffies;
1980 * check addrconf expiration here.
1981 * Routes are expired even if they are in use.
1984 if (rt->rt6i_flags & RTF_EXPIRES && rt->dst.expires) {
1985 if (time_after(now, rt->dst.expires)) {
1986 RT6_TRACE("expiring %p\n", rt);
1992 /* Also age clones in the exception table.
1993 * Note, that clones are aged out
1994 * only if they are not in use now.
1996 rt6_age_exceptions(rt, gc_args, now);
2001 void fib6_run_gc(unsigned long expires, struct net *net, bool force)
2003 struct fib6_gc_args gc_args;
2007 spin_lock_bh(&net->ipv6.fib6_gc_lock);
2008 } else if (!spin_trylock_bh(&net->ipv6.fib6_gc_lock)) {
2009 mod_timer(&net->ipv6.ip6_fib_timer, jiffies + HZ);
2012 gc_args.timeout = expires ? (int)expires :
2013 net->ipv6.sysctl.ip6_rt_gc_interval;
2016 fib6_clean_all(net, fib6_age, &gc_args);
2018 net->ipv6.ip6_rt_last_gc = now;
2021 mod_timer(&net->ipv6.ip6_fib_timer,
2023 + net->ipv6.sysctl.ip6_rt_gc_interval));
2025 del_timer(&net->ipv6.ip6_fib_timer);
2026 spin_unlock_bh(&net->ipv6.fib6_gc_lock);
2029 static void fib6_gc_timer_cb(unsigned long arg)
2031 fib6_run_gc(0, (struct net *)arg, true);
2034 static int __net_init fib6_net_init(struct net *net)
2036 size_t size = sizeof(struct hlist_head) * FIB6_TABLE_HASHSZ;
2039 err = fib6_notifier_init(net);
2043 spin_lock_init(&net->ipv6.fib6_gc_lock);
2044 rwlock_init(&net->ipv6.fib6_walker_lock);
2045 INIT_LIST_HEAD(&net->ipv6.fib6_walkers);
2046 setup_timer(&net->ipv6.ip6_fib_timer, fib6_gc_timer_cb, (unsigned long)net);
2048 net->ipv6.rt6_stats = kzalloc(sizeof(*net->ipv6.rt6_stats), GFP_KERNEL);
2049 if (!net->ipv6.rt6_stats)
2052 /* Avoid false sharing : Use at least a full cache line */
2053 size = max_t(size_t, size, L1_CACHE_BYTES);
2055 net->ipv6.fib_table_hash = kzalloc(size, GFP_KERNEL);
2056 if (!net->ipv6.fib_table_hash)
2059 net->ipv6.fib6_main_tbl = kzalloc(sizeof(*net->ipv6.fib6_main_tbl),
2061 if (!net->ipv6.fib6_main_tbl)
2062 goto out_fib_table_hash;
2064 net->ipv6.fib6_main_tbl->tb6_id = RT6_TABLE_MAIN;
2065 rcu_assign_pointer(net->ipv6.fib6_main_tbl->tb6_root.leaf,
2066 net->ipv6.ip6_null_entry);
2067 net->ipv6.fib6_main_tbl->tb6_root.fn_flags =
2068 RTN_ROOT | RTN_TL_ROOT | RTN_RTINFO;
2069 inet_peer_base_init(&net->ipv6.fib6_main_tbl->tb6_peers);
2071 #ifdef CONFIG_IPV6_MULTIPLE_TABLES
2072 net->ipv6.fib6_local_tbl = kzalloc(sizeof(*net->ipv6.fib6_local_tbl),
2074 if (!net->ipv6.fib6_local_tbl)
2075 goto out_fib6_main_tbl;
2076 net->ipv6.fib6_local_tbl->tb6_id = RT6_TABLE_LOCAL;
2077 rcu_assign_pointer(net->ipv6.fib6_local_tbl->tb6_root.leaf,
2078 net->ipv6.ip6_null_entry);
2079 net->ipv6.fib6_local_tbl->tb6_root.fn_flags =
2080 RTN_ROOT | RTN_TL_ROOT | RTN_RTINFO;
2081 inet_peer_base_init(&net->ipv6.fib6_local_tbl->tb6_peers);
2083 fib6_tables_init(net);
2087 #ifdef CONFIG_IPV6_MULTIPLE_TABLES
2089 kfree(net->ipv6.fib6_main_tbl);
2092 kfree(net->ipv6.fib_table_hash);
2094 kfree(net->ipv6.rt6_stats);
2096 fib6_notifier_exit(net);
2100 static void fib6_net_exit(struct net *net)
2104 rt6_ifdown(net, NULL);
2105 del_timer_sync(&net->ipv6.ip6_fib_timer);
2107 for (i = 0; i < FIB6_TABLE_HASHSZ; i++) {
2108 struct hlist_head *head = &net->ipv6.fib_table_hash[i];
2109 struct hlist_node *tmp;
2110 struct fib6_table *tb;
2112 hlist_for_each_entry_safe(tb, tmp, head, tb6_hlist) {
2113 hlist_del(&tb->tb6_hlist);
2114 fib6_free_table(tb);
2118 kfree(net->ipv6.fib_table_hash);
2119 kfree(net->ipv6.rt6_stats);
2120 fib6_notifier_exit(net);
2123 static struct pernet_operations fib6_net_ops = {
2124 .init = fib6_net_init,
2125 .exit = fib6_net_exit,
2128 int __init fib6_init(void)
2132 fib6_node_kmem = kmem_cache_create("fib6_nodes",
2133 sizeof(struct fib6_node),
2134 0, SLAB_HWCACHE_ALIGN,
2136 if (!fib6_node_kmem)
2139 ret = register_pernet_subsys(&fib6_net_ops);
2141 goto out_kmem_cache_create;
2143 ret = __rtnl_register(PF_INET6, RTM_GETROUTE, NULL, inet6_dump_fib,
2146 goto out_unregister_subsys;
2148 __fib6_flush_trees = fib6_flush_trees;
2152 out_unregister_subsys:
2153 unregister_pernet_subsys(&fib6_net_ops);
2154 out_kmem_cache_create:
2155 kmem_cache_destroy(fib6_node_kmem);
2159 void fib6_gc_cleanup(void)
2161 unregister_pernet_subsys(&fib6_net_ops);
2162 kmem_cache_destroy(fib6_node_kmem);
2165 #ifdef CONFIG_PROC_FS
2167 struct ipv6_route_iter {
2168 struct seq_net_private p;
2169 struct fib6_walker w;
2171 struct fib6_table *tbl;
2175 static int ipv6_route_seq_show(struct seq_file *seq, void *v)
2177 struct rt6_info *rt = v;
2178 struct ipv6_route_iter *iter = seq->private;
2180 seq_printf(seq, "%pi6 %02x ", &rt->rt6i_dst.addr, rt->rt6i_dst.plen);
2182 #ifdef CONFIG_IPV6_SUBTREES
2183 seq_printf(seq, "%pi6 %02x ", &rt->rt6i_src.addr, rt->rt6i_src.plen);
2185 seq_puts(seq, "00000000000000000000000000000000 00 ");
2187 if (rt->rt6i_flags & RTF_GATEWAY)
2188 seq_printf(seq, "%pi6", &rt->rt6i_gateway);
2190 seq_puts(seq, "00000000000000000000000000000000");
2192 seq_printf(seq, " %08x %08x %08x %08x %8s\n",
2193 rt->rt6i_metric, atomic_read(&rt->dst.__refcnt),
2194 rt->dst.__use, rt->rt6i_flags,
2195 rt->dst.dev ? rt->dst.dev->name : "");
2196 iter->w.leaf = NULL;
2200 static int ipv6_route_yield(struct fib6_walker *w)
2202 struct ipv6_route_iter *iter = w->args;
2208 iter->w.leaf = rcu_dereference_protected(
2209 iter->w.leaf->dst.rt6_next,
2210 lockdep_is_held(&iter->tbl->tb6_lock));
2212 if (!iter->skip && iter->w.leaf)
2214 } while (iter->w.leaf);
2219 static void ipv6_route_seq_setup_walk(struct ipv6_route_iter *iter,
2222 memset(&iter->w, 0, sizeof(iter->w));
2223 iter->w.func = ipv6_route_yield;
2224 iter->w.root = &iter->tbl->tb6_root;
2225 iter->w.state = FWS_INIT;
2226 iter->w.node = iter->w.root;
2227 iter->w.args = iter;
2228 iter->sernum = iter->w.root->fn_sernum;
2229 INIT_LIST_HEAD(&iter->w.lh);
2230 fib6_walker_link(net, &iter->w);
2233 static struct fib6_table *ipv6_route_seq_next_table(struct fib6_table *tbl,
2237 struct hlist_node *node;
2240 h = (tbl->tb6_id & (FIB6_TABLE_HASHSZ - 1)) + 1;
2241 node = rcu_dereference_bh(hlist_next_rcu(&tbl->tb6_hlist));
2247 while (!node && h < FIB6_TABLE_HASHSZ) {
2248 node = rcu_dereference_bh(
2249 hlist_first_rcu(&net->ipv6.fib_table_hash[h++]));
2251 return hlist_entry_safe(node, struct fib6_table, tb6_hlist);
2254 static void ipv6_route_check_sernum(struct ipv6_route_iter *iter)
2256 if (iter->sernum != iter->w.root->fn_sernum) {
2257 iter->sernum = iter->w.root->fn_sernum;
2258 iter->w.state = FWS_INIT;
2259 iter->w.node = iter->w.root;
2260 WARN_ON(iter->w.skip);
2261 iter->w.skip = iter->w.count;
2265 static void *ipv6_route_seq_next(struct seq_file *seq, void *v, loff_t *pos)
2269 struct net *net = seq_file_net(seq);
2270 struct ipv6_route_iter *iter = seq->private;
2275 n = rcu_dereference_bh(((struct rt6_info *)v)->dst.rt6_next);
2282 ipv6_route_check_sernum(iter);
2283 spin_lock_bh(&iter->tbl->tb6_lock);
2284 r = fib6_walk_continue(&iter->w);
2285 spin_unlock_bh(&iter->tbl->tb6_lock);
2289 return iter->w.leaf;
2291 fib6_walker_unlink(net, &iter->w);
2294 fib6_walker_unlink(net, &iter->w);
2296 iter->tbl = ipv6_route_seq_next_table(iter->tbl, net);
2300 ipv6_route_seq_setup_walk(iter, net);
2304 static void *ipv6_route_seq_start(struct seq_file *seq, loff_t *pos)
2307 struct net *net = seq_file_net(seq);
2308 struct ipv6_route_iter *iter = seq->private;
2311 iter->tbl = ipv6_route_seq_next_table(NULL, net);
2315 ipv6_route_seq_setup_walk(iter, net);
2316 return ipv6_route_seq_next(seq, NULL, pos);
2322 static bool ipv6_route_iter_active(struct ipv6_route_iter *iter)
2324 struct fib6_walker *w = &iter->w;
2325 return w->node && !(w->state == FWS_U && w->node == w->root);
2328 static void ipv6_route_seq_stop(struct seq_file *seq, void *v)
2331 struct net *net = seq_file_net(seq);
2332 struct ipv6_route_iter *iter = seq->private;
2334 if (ipv6_route_iter_active(iter))
2335 fib6_walker_unlink(net, &iter->w);
2337 rcu_read_unlock_bh();
2340 static const struct seq_operations ipv6_route_seq_ops = {
2341 .start = ipv6_route_seq_start,
2342 .next = ipv6_route_seq_next,
2343 .stop = ipv6_route_seq_stop,
2344 .show = ipv6_route_seq_show
2347 int ipv6_route_open(struct inode *inode, struct file *file)
2349 return seq_open_net(inode, file, &ipv6_route_seq_ops,
2350 sizeof(struct ipv6_route_iter));
2353 #endif /* CONFIG_PROC_FS */