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>
37 #include <net/ip6_fib.h>
38 #include <net/ip6_route.h>
43 #define RT6_TRACE(x...) pr_debug(x)
45 #define RT6_TRACE(x...) do { ; } while (0)
48 static struct kmem_cache *fib6_node_kmem __read_mostly;
53 int (*func)(struct rt6_info *, void *arg);
58 #ifdef CONFIG_IPV6_SUBTREES
59 #define FWS_INIT FWS_S
61 #define FWS_INIT FWS_L
64 static void fib6_prune_clones(struct net *net, struct fib6_node *fn);
65 static struct rt6_info *fib6_find_prefix(struct net *net, struct fib6_node *fn);
66 static struct fib6_node *fib6_repair_tree(struct net *net, struct fib6_node *fn);
67 static int fib6_walk(struct net *net, struct fib6_walker *w);
68 static int fib6_walk_continue(struct fib6_walker *w);
71 * A routing update causes an increase of the serial number on the
72 * affected subtree. This allows for cached routes to be asynchronously
73 * tested when modifications are made to the destination cache as a
74 * result of redirects, path MTU changes, etc.
77 static void fib6_gc_timer_cb(unsigned long arg);
79 #define FOR_WALKERS(net, w) \
80 list_for_each_entry(w, &(net)->ipv6.fib6_walkers, lh)
82 static void fib6_walker_link(struct net *net, struct fib6_walker *w)
84 write_lock_bh(&net->ipv6.fib6_walker_lock);
85 list_add(&w->lh, &net->ipv6.fib6_walkers);
86 write_unlock_bh(&net->ipv6.fib6_walker_lock);
89 static void fib6_walker_unlink(struct net *net, struct fib6_walker *w)
91 write_lock_bh(&net->ipv6.fib6_walker_lock);
93 write_unlock_bh(&net->ipv6.fib6_walker_lock);
96 static int fib6_new_sernum(struct net *net)
101 old = atomic_read(&net->ipv6.fib6_sernum);
102 new = old < INT_MAX ? old + 1 : 1;
103 } while (atomic_cmpxchg(&net->ipv6.fib6_sernum,
109 FIB6_NO_SERNUM_CHANGE = 0,
113 * Auxiliary address test functions for the radix tree.
115 * These assume a 32bit processor (although it will work on
122 #if defined(__LITTLE_ENDIAN)
123 # define BITOP_BE32_SWIZZLE (0x1F & ~7)
125 # define BITOP_BE32_SWIZZLE 0
128 static __be32 addr_bit_set(const void *token, int fn_bit)
130 const __be32 *addr = token;
133 * 1 << ((~fn_bit ^ BITOP_BE32_SWIZZLE) & 0x1f)
134 * is optimized version of
135 * htonl(1 << ((~fn_bit)&0x1F))
136 * See include/asm-generic/bitops/le.h.
138 return (__force __be32)(1 << ((~fn_bit ^ BITOP_BE32_SWIZZLE) & 0x1f)) &
142 static struct fib6_node *node_alloc(void)
144 struct fib6_node *fn;
146 fn = kmem_cache_zalloc(fib6_node_kmem, GFP_ATOMIC);
151 static void node_free(struct fib6_node *fn)
153 kmem_cache_free(fib6_node_kmem, fn);
156 static void rt6_free_pcpu(struct rt6_info *non_pcpu_rt)
160 if (!non_pcpu_rt->rt6i_pcpu)
163 for_each_possible_cpu(cpu) {
164 struct rt6_info **ppcpu_rt;
165 struct rt6_info *pcpu_rt;
167 ppcpu_rt = per_cpu_ptr(non_pcpu_rt->rt6i_pcpu, cpu);
170 dst_dev_put(&pcpu_rt->dst);
171 dst_release(&pcpu_rt->dst);
176 free_percpu(non_pcpu_rt->rt6i_pcpu);
177 non_pcpu_rt->rt6i_pcpu = NULL;
180 static void rt6_release(struct rt6_info *rt)
182 if (atomic_dec_and_test(&rt->rt6i_ref)) {
184 dst_dev_put(&rt->dst);
185 dst_release(&rt->dst);
189 static void fib6_link_table(struct net *net, struct fib6_table *tb)
194 * Initialize table lock at a single place to give lockdep a key,
195 * tables aren't visible prior to being linked to the list.
197 rwlock_init(&tb->tb6_lock);
199 h = tb->tb6_id & (FIB6_TABLE_HASHSZ - 1);
202 * No protection necessary, this is the only list mutatation
203 * operation, tables never disappear once they exist.
205 hlist_add_head_rcu(&tb->tb6_hlist, &net->ipv6.fib_table_hash[h]);
208 #ifdef CONFIG_IPV6_MULTIPLE_TABLES
210 static struct fib6_table *fib6_alloc_table(struct net *net, u32 id)
212 struct fib6_table *table;
214 table = kzalloc(sizeof(*table), GFP_ATOMIC);
217 table->tb6_root.leaf = net->ipv6.ip6_null_entry;
218 table->tb6_root.fn_flags = RTN_ROOT | RTN_TL_ROOT | RTN_RTINFO;
219 inet_peer_base_init(&table->tb6_peers);
225 struct fib6_table *fib6_new_table(struct net *net, u32 id)
227 struct fib6_table *tb;
231 tb = fib6_get_table(net, id);
235 tb = fib6_alloc_table(net, id);
237 fib6_link_table(net, tb);
241 EXPORT_SYMBOL_GPL(fib6_new_table);
243 struct fib6_table *fib6_get_table(struct net *net, u32 id)
245 struct fib6_table *tb;
246 struct hlist_head *head;
251 h = id & (FIB6_TABLE_HASHSZ - 1);
253 head = &net->ipv6.fib_table_hash[h];
254 hlist_for_each_entry_rcu(tb, head, tb6_hlist) {
255 if (tb->tb6_id == id) {
264 EXPORT_SYMBOL_GPL(fib6_get_table);
266 static void __net_init fib6_tables_init(struct net *net)
268 fib6_link_table(net, net->ipv6.fib6_main_tbl);
269 fib6_link_table(net, net->ipv6.fib6_local_tbl);
273 struct fib6_table *fib6_new_table(struct net *net, u32 id)
275 return fib6_get_table(net, id);
278 struct fib6_table *fib6_get_table(struct net *net, u32 id)
280 return net->ipv6.fib6_main_tbl;
283 struct dst_entry *fib6_rule_lookup(struct net *net, struct flowi6 *fl6,
284 int flags, pol_lookup_t lookup)
288 rt = lookup(net, net->ipv6.fib6_main_tbl, fl6, flags);
289 if (rt->dst.error == -EAGAIN) {
291 rt = net->ipv6.ip6_null_entry;
298 static void __net_init fib6_tables_init(struct net *net)
300 fib6_link_table(net, net->ipv6.fib6_main_tbl);
305 static int fib6_dump_node(struct fib6_walker *w)
310 for (rt = w->leaf; rt; rt = rt->dst.rt6_next) {
311 res = rt6_dump_route(rt, w->args);
313 /* Frame is full, suspend walking */
318 /* Multipath routes are dumped in one route with the
319 * RTA_MULTIPATH attribute. Jump 'rt' to point to the
320 * last sibling of this route (no need to dump the
321 * sibling routes again)
323 if (rt->rt6i_nsiblings)
324 rt = list_last_entry(&rt->rt6i_siblings,
332 static void fib6_dump_end(struct netlink_callback *cb)
334 struct net *net = sock_net(cb->skb->sk);
335 struct fib6_walker *w = (void *)cb->args[2];
340 fib6_walker_unlink(net, w);
345 cb->done = (void *)cb->args[3];
349 static int fib6_dump_done(struct netlink_callback *cb)
352 return cb->done ? cb->done(cb) : 0;
355 static int fib6_dump_table(struct fib6_table *table, struct sk_buff *skb,
356 struct netlink_callback *cb)
358 struct net *net = sock_net(skb->sk);
359 struct fib6_walker *w;
362 w = (void *)cb->args[2];
363 w->root = &table->tb6_root;
365 if (cb->args[4] == 0) {
369 read_lock_bh(&table->tb6_lock);
370 res = fib6_walk(net, w);
371 read_unlock_bh(&table->tb6_lock);
374 cb->args[5] = w->root->fn_sernum;
377 if (cb->args[5] != w->root->fn_sernum) {
378 /* Begin at the root if the tree changed */
379 cb->args[5] = w->root->fn_sernum;
386 read_lock_bh(&table->tb6_lock);
387 res = fib6_walk_continue(w);
388 read_unlock_bh(&table->tb6_lock);
390 fib6_walker_unlink(net, w);
398 static int inet6_dump_fib(struct sk_buff *skb, struct netlink_callback *cb)
400 struct net *net = sock_net(skb->sk);
402 unsigned int e = 0, s_e;
403 struct rt6_rtnl_dump_arg arg;
404 struct fib6_walker *w;
405 struct fib6_table *tb;
406 struct hlist_head *head;
412 w = (void *)cb->args[2];
416 * 1. hook callback destructor.
418 cb->args[3] = (long)cb->done;
419 cb->done = fib6_dump_done;
422 * 2. allocate and initialize walker.
424 w = kzalloc(sizeof(*w), GFP_ATOMIC);
427 w->func = fib6_dump_node;
428 cb->args[2] = (long)w;
437 for (h = s_h; h < FIB6_TABLE_HASHSZ; h++, s_e = 0) {
439 head = &net->ipv6.fib_table_hash[h];
440 hlist_for_each_entry_rcu(tb, head, tb6_hlist) {
443 res = fib6_dump_table(tb, skb, cb);
455 res = res < 0 ? res : skb->len;
464 * return the appropriate node for a routing tree "add" operation
465 * by either creating and inserting or by returning an existing
469 static struct fib6_node *fib6_add_1(struct fib6_node *root,
470 struct in6_addr *addr, int plen,
471 int offset, int allow_create,
472 int replace_required, int sernum,
473 struct netlink_ext_ack *extack)
475 struct fib6_node *fn, *in, *ln;
476 struct fib6_node *pn = NULL;
481 RT6_TRACE("fib6_add_1\n");
483 /* insert node in tree */
488 key = (struct rt6key *)((u8 *)fn->leaf + offset);
493 if (plen < fn->fn_bit ||
494 !ipv6_prefix_equal(&key->addr, addr, fn->fn_bit)) {
496 if (replace_required) {
497 NL_SET_ERR_MSG(extack,
498 "Can not replace route - no match found");
499 pr_warn("Can't replace route, no match found\n");
500 return ERR_PTR(-ENOENT);
502 pr_warn("NLM_F_CREATE should be set when creating new route\n");
511 if (plen == fn->fn_bit) {
512 /* clean up an intermediate node */
513 if (!(fn->fn_flags & RTN_RTINFO)) {
514 rt6_release(fn->leaf);
518 fn->fn_sernum = sernum;
524 * We have more bits to go
527 /* Try to walk down on tree. */
528 fn->fn_sernum = sernum;
529 dir = addr_bit_set(addr, fn->fn_bit);
531 fn = dir ? fn->right : fn->left;
535 /* We should not create new node because
536 * NLM_F_REPLACE was specified without NLM_F_CREATE
537 * I assume it is safe to require NLM_F_CREATE when
538 * REPLACE flag is used! Later we may want to remove the
539 * check for replace_required, because according
540 * to netlink specification, NLM_F_CREATE
541 * MUST be specified if new route is created.
542 * That would keep IPv6 consistent with IPv4
544 if (replace_required) {
545 NL_SET_ERR_MSG(extack,
546 "Can not replace route - no match found");
547 pr_warn("Can't replace route, no match found\n");
548 return ERR_PTR(-ENOENT);
550 pr_warn("NLM_F_CREATE should be set when creating new route\n");
553 * We walked to the bottom of tree.
554 * Create new leaf node without children.
560 return ERR_PTR(-ENOMEM);
564 ln->fn_sernum = sernum;
576 * split since we don't have a common prefix anymore or
577 * we have a less significant route.
578 * we've to insert an intermediate node on the list
579 * this new node will point to the one we need to create
585 /* find 1st bit in difference between the 2 addrs.
587 See comment in __ipv6_addr_diff: bit may be an invalid value,
588 but if it is >= plen, the value is ignored in any case.
591 bit = __ipv6_addr_diff(addr, &key->addr, sizeof(*addr));
596 * (new leaf node)[ln] (old node)[fn]
607 return ERR_PTR(-ENOMEM);
611 * new intermediate node.
613 * be off since that an address that chooses one of
614 * the branches would not match less specific routes
615 * in the other branch
622 atomic_inc(&in->leaf->rt6i_ref);
624 in->fn_sernum = sernum;
626 /* update parent pointer */
637 ln->fn_sernum = sernum;
639 if (addr_bit_set(addr, bit)) {
646 } else { /* plen <= bit */
649 * (new leaf node)[ln]
651 * (old node)[fn] NULL
657 return ERR_PTR(-ENOMEM);
663 ln->fn_sernum = sernum;
670 if (addr_bit_set(&key->addr, plen))
680 static bool rt6_qualify_for_ecmp(struct rt6_info *rt)
682 return (rt->rt6i_flags & (RTF_GATEWAY|RTF_ADDRCONF|RTF_DYNAMIC)) ==
686 static void fib6_copy_metrics(u32 *mp, const struct mx6_config *mxc)
690 for (i = 0; i < RTAX_MAX; i++) {
691 if (test_bit(i, mxc->mx_valid))
696 static int fib6_commit_metrics(struct dst_entry *dst, struct mx6_config *mxc)
701 if (dst->flags & DST_HOST) {
702 u32 *mp = dst_metrics_write_ptr(dst);
707 fib6_copy_metrics(mp, mxc);
709 dst_init_metrics(dst, mxc->mx, false);
711 /* We've stolen mx now. */
718 static void fib6_purge_rt(struct rt6_info *rt, struct fib6_node *fn,
721 if (atomic_read(&rt->rt6i_ref) != 1) {
722 /* This route is used as dummy address holder in some split
723 * nodes. It is not leaked, but it still holds other resources,
724 * which must be released in time. So, scan ascendant nodes
725 * and replace dummy references to this route with references
726 * to still alive ones.
729 if (!(fn->fn_flags & RTN_RTINFO) && fn->leaf == rt) {
730 fn->leaf = fib6_find_prefix(net, fn);
731 atomic_inc(&fn->leaf->rt6i_ref);
736 /* No more references are possible at this point. */
737 BUG_ON(atomic_read(&rt->rt6i_ref) != 1);
742 * Insert routing information in a node.
745 static int fib6_add_rt2node(struct fib6_node *fn, struct rt6_info *rt,
746 struct nl_info *info, struct mx6_config *mxc)
748 struct rt6_info *iter = NULL;
749 struct rt6_info **ins;
750 struct rt6_info **fallback_ins = NULL;
751 int replace = (info->nlh &&
752 (info->nlh->nlmsg_flags & NLM_F_REPLACE));
753 int add = (!info->nlh ||
754 (info->nlh->nlmsg_flags & NLM_F_CREATE));
756 bool rt_can_ecmp = rt6_qualify_for_ecmp(rt);
757 u16 nlflags = NLM_F_EXCL;
760 if (info->nlh && (info->nlh->nlmsg_flags & NLM_F_APPEND))
761 nlflags |= NLM_F_APPEND;
765 for (iter = fn->leaf; iter; iter = iter->dst.rt6_next) {
767 * Search for duplicates
770 if (iter->rt6i_metric == rt->rt6i_metric) {
772 * Same priority level
775 (info->nlh->nlmsg_flags & NLM_F_EXCL))
778 nlflags &= ~NLM_F_EXCL;
780 if (rt_can_ecmp == rt6_qualify_for_ecmp(iter)) {
785 fallback_ins = fallback_ins ?: ins;
789 if (rt6_duplicate_nexthop(iter, rt)) {
790 if (rt->rt6i_nsiblings)
791 rt->rt6i_nsiblings = 0;
792 if (!(iter->rt6i_flags & RTF_EXPIRES))
794 if (!(rt->rt6i_flags & RTF_EXPIRES))
795 rt6_clean_expires(iter);
797 rt6_set_expires(iter, rt->dst.expires);
798 iter->rt6i_pmtu = rt->rt6i_pmtu;
801 /* If we have the same destination and the same metric,
802 * but not the same gateway, then the route we try to
803 * add is sibling to this route, increment our counter
804 * of siblings, and later we will add our route to the
806 * Only static routes (which don't have flag
807 * RTF_EXPIRES) are used for ECMPv6.
809 * To avoid long list, we only had siblings if the
810 * route have a gateway.
813 rt6_qualify_for_ecmp(iter))
814 rt->rt6i_nsiblings++;
817 if (iter->rt6i_metric > rt->rt6i_metric)
821 ins = &iter->dst.rt6_next;
824 if (fallback_ins && !found) {
825 /* No ECMP-able route found, replace first non-ECMP one */
831 /* Reset round-robin state, if necessary */
832 if (ins == &fn->leaf)
835 /* Link this route to others same route. */
836 if (rt->rt6i_nsiblings) {
837 unsigned int rt6i_nsiblings;
838 struct rt6_info *sibling, *temp_sibling;
840 /* Find the first route that have the same metric */
843 if (sibling->rt6i_metric == rt->rt6i_metric &&
844 rt6_qualify_for_ecmp(sibling)) {
845 list_add_tail(&rt->rt6i_siblings,
846 &sibling->rt6i_siblings);
849 sibling = sibling->dst.rt6_next;
851 /* For each sibling in the list, increment the counter of
852 * siblings. BUG() if counters does not match, list of siblings
856 list_for_each_entry_safe(sibling, temp_sibling,
857 &rt->rt6i_siblings, rt6i_siblings) {
858 sibling->rt6i_nsiblings++;
859 BUG_ON(sibling->rt6i_nsiblings != rt->rt6i_nsiblings);
862 BUG_ON(rt6i_nsiblings != rt->rt6i_nsiblings);
870 pr_warn("NLM_F_CREATE should be set when creating new route\n");
873 nlflags |= NLM_F_CREATE;
874 err = fib6_commit_metrics(&rt->dst, mxc);
878 rt->dst.rt6_next = iter;
881 atomic_inc(&rt->rt6i_ref);
882 if (!info->skip_notify)
883 inet6_rt_notify(RTM_NEWROUTE, rt, info, nlflags);
884 info->nl_net->ipv6.rt6_stats->fib_rt_entries++;
886 if (!(fn->fn_flags & RTN_RTINFO)) {
887 info->nl_net->ipv6.rt6_stats->fib_route_nodes++;
888 fn->fn_flags |= RTN_RTINFO;
897 pr_warn("NLM_F_REPLACE set, but no existing node found!\n");
901 err = fib6_commit_metrics(&rt->dst, mxc);
907 rt->dst.rt6_next = iter->dst.rt6_next;
908 atomic_inc(&rt->rt6i_ref);
909 if (!info->skip_notify)
910 inet6_rt_notify(RTM_NEWROUTE, rt, info, NLM_F_REPLACE);
911 if (!(fn->fn_flags & RTN_RTINFO)) {
912 info->nl_net->ipv6.rt6_stats->fib_route_nodes++;
913 fn->fn_flags |= RTN_RTINFO;
915 nsiblings = iter->rt6i_nsiblings;
916 fib6_purge_rt(iter, fn, info->nl_net);
920 /* Replacing an ECMP route, remove all siblings */
921 ins = &rt->dst.rt6_next;
924 if (iter->rt6i_metric > rt->rt6i_metric)
926 if (rt6_qualify_for_ecmp(iter)) {
927 *ins = iter->dst.rt6_next;
928 fib6_purge_rt(iter, fn, info->nl_net);
932 ins = &iter->dst.rt6_next;
936 WARN_ON(nsiblings != 0);
943 static void fib6_start_gc(struct net *net, struct rt6_info *rt)
945 if (!timer_pending(&net->ipv6.ip6_fib_timer) &&
946 (rt->rt6i_flags & (RTF_EXPIRES | RTF_CACHE)))
947 mod_timer(&net->ipv6.ip6_fib_timer,
948 jiffies + net->ipv6.sysctl.ip6_rt_gc_interval);
951 void fib6_force_start_gc(struct net *net)
953 if (!timer_pending(&net->ipv6.ip6_fib_timer))
954 mod_timer(&net->ipv6.ip6_fib_timer,
955 jiffies + net->ipv6.sysctl.ip6_rt_gc_interval);
959 * Add routing information to the routing tree.
960 * <destination addr>/<source addr>
961 * with source addr info in sub-trees
964 int fib6_add(struct fib6_node *root, struct rt6_info *rt,
965 struct nl_info *info, struct mx6_config *mxc,
966 struct netlink_ext_ack *extack)
968 struct fib6_node *fn, *pn = NULL;
970 int allow_create = 1;
971 int replace_required = 0;
972 int sernum = fib6_new_sernum(info->nl_net);
974 if (WARN_ON_ONCE(!atomic_read(&rt->dst.__refcnt)))
978 if (!(info->nlh->nlmsg_flags & NLM_F_CREATE))
980 if (info->nlh->nlmsg_flags & NLM_F_REPLACE)
981 replace_required = 1;
983 if (!allow_create && !replace_required)
984 pr_warn("RTM_NEWROUTE with no NLM_F_CREATE or NLM_F_REPLACE\n");
986 fn = fib6_add_1(root, &rt->rt6i_dst.addr, rt->rt6i_dst.plen,
987 offsetof(struct rt6_info, rt6i_dst), allow_create,
988 replace_required, sernum, extack);
997 #ifdef CONFIG_IPV6_SUBTREES
998 if (rt->rt6i_src.plen) {
999 struct fib6_node *sn;
1002 struct fib6_node *sfn;
1014 /* Create subtree root node */
1019 sfn->leaf = info->nl_net->ipv6.ip6_null_entry;
1020 atomic_inc(&info->nl_net->ipv6.ip6_null_entry->rt6i_ref);
1021 sfn->fn_flags = RTN_ROOT;
1022 sfn->fn_sernum = sernum;
1024 /* Now add the first leaf node to new subtree */
1026 sn = fib6_add_1(sfn, &rt->rt6i_src.addr,
1028 offsetof(struct rt6_info, rt6i_src),
1029 allow_create, replace_required, sernum,
1033 /* If it is failed, discard just allocated
1034 root, and then (in st_failure) stale node
1042 /* Now link new subtree to main tree */
1046 sn = fib6_add_1(fn->subtree, &rt->rt6i_src.addr,
1048 offsetof(struct rt6_info, rt6i_src),
1049 allow_create, replace_required, sernum,
1060 atomic_inc(&rt->rt6i_ref);
1066 err = fib6_add_rt2node(fn, rt, info, mxc);
1068 fib6_start_gc(info->nl_net, rt);
1069 if (!(rt->rt6i_flags & RTF_CACHE))
1070 fib6_prune_clones(info->nl_net, pn);
1075 #ifdef CONFIG_IPV6_SUBTREES
1077 * If fib6_add_1 has cleared the old leaf pointer in the
1078 * super-tree leaf node we have to find a new one for it.
1080 if (pn != fn && pn->leaf == rt) {
1082 atomic_dec(&rt->rt6i_ref);
1084 if (pn != fn && !pn->leaf && !(pn->fn_flags & RTN_RTINFO)) {
1085 pn->leaf = fib6_find_prefix(info->nl_net, pn);
1088 WARN_ON(pn->leaf == NULL);
1089 pn->leaf = info->nl_net->ipv6.ip6_null_entry;
1092 atomic_inc(&pn->leaf->rt6i_ref);
1095 /* Always release dst as dst->__refcnt is guaranteed
1096 * to be taken before entering this function
1098 dst_release_immediate(&rt->dst);
1102 #ifdef CONFIG_IPV6_SUBTREES
1103 /* Subtree creation failed, probably main tree node
1104 is orphan. If it is, shoot it.
1107 if (fn && !(fn->fn_flags & (RTN_RTINFO|RTN_ROOT)))
1108 fib6_repair_tree(info->nl_net, fn);
1109 /* Always release dst as dst->__refcnt is guaranteed
1110 * to be taken before entering this function
1112 dst_release_immediate(&rt->dst);
1118 * Routing tree lookup
1122 struct lookup_args {
1123 int offset; /* key offset on rt6_info */
1124 const struct in6_addr *addr; /* search key */
1127 static struct fib6_node *fib6_lookup_1(struct fib6_node *root,
1128 struct lookup_args *args)
1130 struct fib6_node *fn;
1133 if (unlikely(args->offset == 0))
1143 struct fib6_node *next;
1145 dir = addr_bit_set(args->addr, fn->fn_bit);
1147 next = dir ? fn->right : fn->left;
1157 if (FIB6_SUBTREE(fn) || fn->fn_flags & RTN_RTINFO) {
1160 key = (struct rt6key *) ((u8 *) fn->leaf +
1163 if (ipv6_prefix_equal(&key->addr, args->addr, key->plen)) {
1164 #ifdef CONFIG_IPV6_SUBTREES
1166 struct fib6_node *sfn;
1167 sfn = fib6_lookup_1(fn->subtree,
1174 if (fn->fn_flags & RTN_RTINFO)
1178 #ifdef CONFIG_IPV6_SUBTREES
1181 if (fn->fn_flags & RTN_ROOT)
1190 struct fib6_node *fib6_lookup(struct fib6_node *root, const struct in6_addr *daddr,
1191 const struct in6_addr *saddr)
1193 struct fib6_node *fn;
1194 struct lookup_args args[] = {
1196 .offset = offsetof(struct rt6_info, rt6i_dst),
1199 #ifdef CONFIG_IPV6_SUBTREES
1201 .offset = offsetof(struct rt6_info, rt6i_src),
1206 .offset = 0, /* sentinel */
1210 fn = fib6_lookup_1(root, daddr ? args : args + 1);
1211 if (!fn || fn->fn_flags & RTN_TL_ROOT)
1218 * Get node with specified destination prefix (and source prefix,
1219 * if subtrees are used)
1223 static struct fib6_node *fib6_locate_1(struct fib6_node *root,
1224 const struct in6_addr *addr,
1225 int plen, int offset)
1227 struct fib6_node *fn;
1229 for (fn = root; fn ; ) {
1230 struct rt6key *key = (struct rt6key *)((u8 *)fn->leaf + offset);
1235 if (plen < fn->fn_bit ||
1236 !ipv6_prefix_equal(&key->addr, addr, fn->fn_bit))
1239 if (plen == fn->fn_bit)
1243 * We have more bits to go
1245 if (addr_bit_set(addr, fn->fn_bit))
1253 struct fib6_node *fib6_locate(struct fib6_node *root,
1254 const struct in6_addr *daddr, int dst_len,
1255 const struct in6_addr *saddr, int src_len)
1257 struct fib6_node *fn;
1259 fn = fib6_locate_1(root, daddr, dst_len,
1260 offsetof(struct rt6_info, rt6i_dst));
1262 #ifdef CONFIG_IPV6_SUBTREES
1264 WARN_ON(saddr == NULL);
1265 if (fn && fn->subtree)
1266 fn = fib6_locate_1(fn->subtree, saddr, src_len,
1267 offsetof(struct rt6_info, rt6i_src));
1271 if (fn && fn->fn_flags & RTN_RTINFO)
1283 static struct rt6_info *fib6_find_prefix(struct net *net, struct fib6_node *fn)
1285 if (fn->fn_flags & RTN_ROOT)
1286 return net->ipv6.ip6_null_entry;
1290 return fn->left->leaf;
1292 return fn->right->leaf;
1294 fn = FIB6_SUBTREE(fn);
1300 * Called to trim the tree of intermediate nodes when possible. "fn"
1301 * is the node we want to try and remove.
1304 static struct fib6_node *fib6_repair_tree(struct net *net,
1305 struct fib6_node *fn)
1309 struct fib6_node *child, *pn;
1310 struct fib6_walker *w;
1314 RT6_TRACE("fixing tree: plen=%d iter=%d\n", fn->fn_bit, iter);
1317 WARN_ON(fn->fn_flags & RTN_RTINFO);
1318 WARN_ON(fn->fn_flags & RTN_TL_ROOT);
1324 child = fn->right, children |= 1;
1326 child = fn->left, children |= 2;
1328 if (children == 3 || FIB6_SUBTREE(fn)
1329 #ifdef CONFIG_IPV6_SUBTREES
1330 /* Subtree root (i.e. fn) may have one child */
1331 || (children && fn->fn_flags & RTN_ROOT)
1334 fn->leaf = fib6_find_prefix(net, fn);
1338 fn->leaf = net->ipv6.ip6_null_entry;
1341 atomic_inc(&fn->leaf->rt6i_ref);
1346 #ifdef CONFIG_IPV6_SUBTREES
1347 if (FIB6_SUBTREE(pn) == fn) {
1348 WARN_ON(!(fn->fn_flags & RTN_ROOT));
1349 FIB6_SUBTREE(pn) = NULL;
1352 WARN_ON(fn->fn_flags & RTN_ROOT);
1354 if (pn->right == fn)
1356 else if (pn->left == fn)
1365 #ifdef CONFIG_IPV6_SUBTREES
1369 read_lock(&net->ipv6.fib6_walker_lock);
1370 FOR_WALKERS(net, w) {
1372 if (w->root == fn) {
1373 w->root = w->node = NULL;
1374 RT6_TRACE("W %p adjusted by delroot 1\n", w);
1375 } else if (w->node == fn) {
1376 RT6_TRACE("W %p adjusted by delnode 1, s=%d/%d\n", w, w->state, nstate);
1381 if (w->root == fn) {
1383 RT6_TRACE("W %p adjusted by delroot 2\n", w);
1385 if (w->node == fn) {
1388 RT6_TRACE("W %p adjusted by delnode 2, s=%d\n", w, w->state);
1389 w->state = w->state >= FWS_R ? FWS_U : FWS_INIT;
1391 RT6_TRACE("W %p adjusted by delnode 2, s=%d\n", w, w->state);
1392 w->state = w->state >= FWS_C ? FWS_U : FWS_INIT;
1397 read_unlock(&net->ipv6.fib6_walker_lock);
1400 if (pn->fn_flags & RTN_RTINFO || FIB6_SUBTREE(pn))
1403 rt6_release(pn->leaf);
1409 static void fib6_del_route(struct fib6_node *fn, struct rt6_info **rtp,
1410 struct nl_info *info)
1412 struct fib6_walker *w;
1413 struct rt6_info *rt = *rtp;
1414 struct net *net = info->nl_net;
1416 RT6_TRACE("fib6_del_route\n");
1419 *rtp = rt->dst.rt6_next;
1420 rt->rt6i_node = NULL;
1421 net->ipv6.rt6_stats->fib_rt_entries--;
1422 net->ipv6.rt6_stats->fib_discarded_routes++;
1424 /* Reset round-robin state, if necessary */
1425 if (fn->rr_ptr == rt)
1428 /* Remove this entry from other siblings */
1429 if (rt->rt6i_nsiblings) {
1430 struct rt6_info *sibling, *next_sibling;
1432 list_for_each_entry_safe(sibling, next_sibling,
1433 &rt->rt6i_siblings, rt6i_siblings)
1434 sibling->rt6i_nsiblings--;
1435 rt->rt6i_nsiblings = 0;
1436 list_del_init(&rt->rt6i_siblings);
1439 /* Adjust walkers */
1440 read_lock(&net->ipv6.fib6_walker_lock);
1441 FOR_WALKERS(net, w) {
1442 if (w->state == FWS_C && w->leaf == rt) {
1443 RT6_TRACE("walker %p adjusted by delroute\n", w);
1444 w->leaf = rt->dst.rt6_next;
1449 read_unlock(&net->ipv6.fib6_walker_lock);
1451 rt->dst.rt6_next = NULL;
1453 /* If it was last route, expunge its radix tree node */
1455 fn->fn_flags &= ~RTN_RTINFO;
1456 net->ipv6.rt6_stats->fib_route_nodes--;
1457 fn = fib6_repair_tree(net, fn);
1460 fib6_purge_rt(rt, fn, net);
1462 if (!info->skip_notify)
1463 inet6_rt_notify(RTM_DELROUTE, rt, info, 0);
1467 int fib6_del(struct rt6_info *rt, struct nl_info *info)
1469 struct net *net = info->nl_net;
1470 struct fib6_node *fn = rt->rt6i_node;
1471 struct rt6_info **rtp;
1474 if (rt->dst.obsolete > 0) {
1479 if (!fn || rt == net->ipv6.ip6_null_entry)
1482 WARN_ON(!(fn->fn_flags & RTN_RTINFO));
1484 if (!(rt->rt6i_flags & RTF_CACHE)) {
1485 struct fib6_node *pn = fn;
1486 #ifdef CONFIG_IPV6_SUBTREES
1487 /* clones of this route might be in another subtree */
1488 if (rt->rt6i_src.plen) {
1489 while (!(pn->fn_flags & RTN_ROOT))
1494 fib6_prune_clones(info->nl_net, pn);
1498 * Walk the leaf entries looking for ourself
1501 for (rtp = &fn->leaf; *rtp; rtp = &(*rtp)->dst.rt6_next) {
1503 fib6_del_route(fn, rtp, info);
1511 * Tree traversal function.
1513 * Certainly, it is not interrupt safe.
1514 * However, it is internally reenterable wrt itself and fib6_add/fib6_del.
1515 * It means, that we can modify tree during walking
1516 * and use this function for garbage collection, clone pruning,
1517 * cleaning tree when a device goes down etc. etc.
1519 * It guarantees that every node will be traversed,
1520 * and that it will be traversed only once.
1522 * Callback function w->func may return:
1523 * 0 -> continue walking.
1524 * positive value -> walking is suspended (used by tree dumps,
1525 * and probably by gc, if it will be split to several slices)
1526 * negative value -> terminate walking.
1528 * The function itself returns:
1529 * 0 -> walk is complete.
1530 * >0 -> walk is incomplete (i.e. suspended)
1531 * <0 -> walk is terminated by an error.
1534 static int fib6_walk_continue(struct fib6_walker *w)
1536 struct fib6_node *fn, *pn;
1543 if (w->prune && fn != w->root &&
1544 fn->fn_flags & RTN_RTINFO && w->state < FWS_C) {
1549 #ifdef CONFIG_IPV6_SUBTREES
1551 if (FIB6_SUBTREE(fn)) {
1552 w->node = FIB6_SUBTREE(fn);
1560 w->state = FWS_INIT;
1566 w->node = fn->right;
1567 w->state = FWS_INIT;
1573 if (w->leaf && fn->fn_flags & RTN_RTINFO) {
1595 #ifdef CONFIG_IPV6_SUBTREES
1596 if (FIB6_SUBTREE(pn) == fn) {
1597 WARN_ON(!(fn->fn_flags & RTN_ROOT));
1602 if (pn->left == fn) {
1606 if (pn->right == fn) {
1608 w->leaf = w->node->leaf;
1618 static int fib6_walk(struct net *net, struct fib6_walker *w)
1622 w->state = FWS_INIT;
1625 fib6_walker_link(net, w);
1626 res = fib6_walk_continue(w);
1628 fib6_walker_unlink(net, w);
1632 static int fib6_clean_node(struct fib6_walker *w)
1635 struct rt6_info *rt;
1636 struct fib6_cleaner *c = container_of(w, struct fib6_cleaner, w);
1637 struct nl_info info = {
1641 if (c->sernum != FIB6_NO_SERNUM_CHANGE &&
1642 w->node->fn_sernum != c->sernum)
1643 w->node->fn_sernum = c->sernum;
1646 WARN_ON_ONCE(c->sernum == FIB6_NO_SERNUM_CHANGE);
1651 for (rt = w->leaf; rt; rt = rt->dst.rt6_next) {
1652 res = c->func(rt, c->arg);
1655 res = fib6_del(rt, &info);
1658 pr_debug("%s: del failed: rt=%p@%p err=%d\n",
1659 __func__, rt, rt->rt6i_node, res);
1672 * Convenient frontend to tree walker.
1674 * func is called on each route.
1675 * It may return -1 -> delete this route.
1676 * 0 -> continue walking
1678 * prune==1 -> only immediate children of node (certainly,
1679 * ignoring pure split nodes) will be scanned.
1682 static void fib6_clean_tree(struct net *net, struct fib6_node *root,
1683 int (*func)(struct rt6_info *, void *arg),
1684 bool prune, int sernum, void *arg)
1686 struct fib6_cleaner c;
1689 c.w.func = fib6_clean_node;
1698 fib6_walk(net, &c.w);
1701 static void __fib6_clean_all(struct net *net,
1702 int (*func)(struct rt6_info *, void *),
1703 int sernum, void *arg)
1705 struct fib6_table *table;
1706 struct hlist_head *head;
1710 for (h = 0; h < FIB6_TABLE_HASHSZ; h++) {
1711 head = &net->ipv6.fib_table_hash[h];
1712 hlist_for_each_entry_rcu(table, head, tb6_hlist) {
1713 write_lock_bh(&table->tb6_lock);
1714 fib6_clean_tree(net, &table->tb6_root,
1715 func, false, sernum, arg);
1716 write_unlock_bh(&table->tb6_lock);
1722 void fib6_clean_all(struct net *net, int (*func)(struct rt6_info *, void *),
1725 __fib6_clean_all(net, func, FIB6_NO_SERNUM_CHANGE, arg);
1728 static int fib6_prune_clone(struct rt6_info *rt, void *arg)
1730 if (rt->rt6i_flags & RTF_CACHE) {
1731 RT6_TRACE("pruning clone %p\n", rt);
1738 static void fib6_prune_clones(struct net *net, struct fib6_node *fn)
1740 fib6_clean_tree(net, fn, fib6_prune_clone, true,
1741 FIB6_NO_SERNUM_CHANGE, NULL);
1744 static void fib6_flush_trees(struct net *net)
1746 int new_sernum = fib6_new_sernum(net);
1748 __fib6_clean_all(net, NULL, new_sernum, NULL);
1752 * Garbage collection
1761 static int fib6_age(struct rt6_info *rt, void *arg)
1763 struct fib6_gc_args *gc_args = arg;
1764 unsigned long now = jiffies;
1767 * check addrconf expiration here.
1768 * Routes are expired even if they are in use.
1770 * Also age clones. Note, that clones are aged out
1771 * only if they are not in use now.
1774 if (rt->rt6i_flags & RTF_EXPIRES && rt->dst.expires) {
1775 if (time_after(now, rt->dst.expires)) {
1776 RT6_TRACE("expiring %p\n", rt);
1780 } else if (rt->rt6i_flags & RTF_CACHE) {
1781 if (atomic_read(&rt->dst.__refcnt) == 1 &&
1782 time_after_eq(now, rt->dst.lastuse + gc_args->timeout)) {
1783 RT6_TRACE("aging clone %p\n", rt);
1785 } else if (rt->rt6i_flags & RTF_GATEWAY) {
1786 struct neighbour *neigh;
1787 __u8 neigh_flags = 0;
1789 neigh = dst_neigh_lookup(&rt->dst, &rt->rt6i_gateway);
1791 neigh_flags = neigh->flags;
1792 neigh_release(neigh);
1794 if (!(neigh_flags & NTF_ROUTER)) {
1795 RT6_TRACE("purging route %p via non-router but gateway\n",
1806 void fib6_run_gc(unsigned long expires, struct net *net, bool force)
1808 struct fib6_gc_args gc_args;
1812 spin_lock_bh(&net->ipv6.fib6_gc_lock);
1813 } else if (!spin_trylock_bh(&net->ipv6.fib6_gc_lock)) {
1814 mod_timer(&net->ipv6.ip6_fib_timer, jiffies + HZ);
1817 gc_args.timeout = expires ? (int)expires :
1818 net->ipv6.sysctl.ip6_rt_gc_interval;
1821 fib6_clean_all(net, fib6_age, &gc_args);
1823 net->ipv6.ip6_rt_last_gc = now;
1826 mod_timer(&net->ipv6.ip6_fib_timer,
1828 + net->ipv6.sysctl.ip6_rt_gc_interval));
1830 del_timer(&net->ipv6.ip6_fib_timer);
1831 spin_unlock_bh(&net->ipv6.fib6_gc_lock);
1834 static void fib6_gc_timer_cb(unsigned long arg)
1836 fib6_run_gc(0, (struct net *)arg, true);
1839 static int __net_init fib6_net_init(struct net *net)
1841 size_t size = sizeof(struct hlist_head) * FIB6_TABLE_HASHSZ;
1843 spin_lock_init(&net->ipv6.fib6_gc_lock);
1844 rwlock_init(&net->ipv6.fib6_walker_lock);
1845 INIT_LIST_HEAD(&net->ipv6.fib6_walkers);
1846 setup_timer(&net->ipv6.ip6_fib_timer, fib6_gc_timer_cb, (unsigned long)net);
1848 net->ipv6.rt6_stats = kzalloc(sizeof(*net->ipv6.rt6_stats), GFP_KERNEL);
1849 if (!net->ipv6.rt6_stats)
1852 /* Avoid false sharing : Use at least a full cache line */
1853 size = max_t(size_t, size, L1_CACHE_BYTES);
1855 net->ipv6.fib_table_hash = kzalloc(size, GFP_KERNEL);
1856 if (!net->ipv6.fib_table_hash)
1859 net->ipv6.fib6_main_tbl = kzalloc(sizeof(*net->ipv6.fib6_main_tbl),
1861 if (!net->ipv6.fib6_main_tbl)
1862 goto out_fib_table_hash;
1864 net->ipv6.fib6_main_tbl->tb6_id = RT6_TABLE_MAIN;
1865 net->ipv6.fib6_main_tbl->tb6_root.leaf = net->ipv6.ip6_null_entry;
1866 net->ipv6.fib6_main_tbl->tb6_root.fn_flags =
1867 RTN_ROOT | RTN_TL_ROOT | RTN_RTINFO;
1868 inet_peer_base_init(&net->ipv6.fib6_main_tbl->tb6_peers);
1870 #ifdef CONFIG_IPV6_MULTIPLE_TABLES
1871 net->ipv6.fib6_local_tbl = kzalloc(sizeof(*net->ipv6.fib6_local_tbl),
1873 if (!net->ipv6.fib6_local_tbl)
1874 goto out_fib6_main_tbl;
1875 net->ipv6.fib6_local_tbl->tb6_id = RT6_TABLE_LOCAL;
1876 net->ipv6.fib6_local_tbl->tb6_root.leaf = net->ipv6.ip6_null_entry;
1877 net->ipv6.fib6_local_tbl->tb6_root.fn_flags =
1878 RTN_ROOT | RTN_TL_ROOT | RTN_RTINFO;
1879 inet_peer_base_init(&net->ipv6.fib6_local_tbl->tb6_peers);
1881 fib6_tables_init(net);
1885 #ifdef CONFIG_IPV6_MULTIPLE_TABLES
1887 kfree(net->ipv6.fib6_main_tbl);
1890 kfree(net->ipv6.fib_table_hash);
1892 kfree(net->ipv6.rt6_stats);
1897 static void fib6_net_exit(struct net *net)
1899 rt6_ifdown(net, NULL);
1900 del_timer_sync(&net->ipv6.ip6_fib_timer);
1902 #ifdef CONFIG_IPV6_MULTIPLE_TABLES
1903 inetpeer_invalidate_tree(&net->ipv6.fib6_local_tbl->tb6_peers);
1904 kfree(net->ipv6.fib6_local_tbl);
1906 inetpeer_invalidate_tree(&net->ipv6.fib6_main_tbl->tb6_peers);
1907 kfree(net->ipv6.fib6_main_tbl);
1908 kfree(net->ipv6.fib_table_hash);
1909 kfree(net->ipv6.rt6_stats);
1912 static struct pernet_operations fib6_net_ops = {
1913 .init = fib6_net_init,
1914 .exit = fib6_net_exit,
1917 int __init fib6_init(void)
1921 fib6_node_kmem = kmem_cache_create("fib6_nodes",
1922 sizeof(struct fib6_node),
1923 0, SLAB_HWCACHE_ALIGN,
1925 if (!fib6_node_kmem)
1928 ret = register_pernet_subsys(&fib6_net_ops);
1930 goto out_kmem_cache_create;
1932 ret = __rtnl_register(PF_INET6, RTM_GETROUTE, NULL, inet6_dump_fib,
1935 goto out_unregister_subsys;
1937 __fib6_flush_trees = fib6_flush_trees;
1941 out_unregister_subsys:
1942 unregister_pernet_subsys(&fib6_net_ops);
1943 out_kmem_cache_create:
1944 kmem_cache_destroy(fib6_node_kmem);
1948 void fib6_gc_cleanup(void)
1950 unregister_pernet_subsys(&fib6_net_ops);
1951 kmem_cache_destroy(fib6_node_kmem);
1954 #ifdef CONFIG_PROC_FS
1956 struct ipv6_route_iter {
1957 struct seq_net_private p;
1958 struct fib6_walker w;
1960 struct fib6_table *tbl;
1964 static int ipv6_route_seq_show(struct seq_file *seq, void *v)
1966 struct rt6_info *rt = v;
1967 struct ipv6_route_iter *iter = seq->private;
1969 seq_printf(seq, "%pi6 %02x ", &rt->rt6i_dst.addr, rt->rt6i_dst.plen);
1971 #ifdef CONFIG_IPV6_SUBTREES
1972 seq_printf(seq, "%pi6 %02x ", &rt->rt6i_src.addr, rt->rt6i_src.plen);
1974 seq_puts(seq, "00000000000000000000000000000000 00 ");
1976 if (rt->rt6i_flags & RTF_GATEWAY)
1977 seq_printf(seq, "%pi6", &rt->rt6i_gateway);
1979 seq_puts(seq, "00000000000000000000000000000000");
1981 seq_printf(seq, " %08x %08x %08x %08x %8s\n",
1982 rt->rt6i_metric, atomic_read(&rt->dst.__refcnt),
1983 rt->dst.__use, rt->rt6i_flags,
1984 rt->dst.dev ? rt->dst.dev->name : "");
1985 iter->w.leaf = NULL;
1989 static int ipv6_route_yield(struct fib6_walker *w)
1991 struct ipv6_route_iter *iter = w->args;
1997 iter->w.leaf = iter->w.leaf->dst.rt6_next;
1999 if (!iter->skip && iter->w.leaf)
2001 } while (iter->w.leaf);
2006 static void ipv6_route_seq_setup_walk(struct ipv6_route_iter *iter,
2009 memset(&iter->w, 0, sizeof(iter->w));
2010 iter->w.func = ipv6_route_yield;
2011 iter->w.root = &iter->tbl->tb6_root;
2012 iter->w.state = FWS_INIT;
2013 iter->w.node = iter->w.root;
2014 iter->w.args = iter;
2015 iter->sernum = iter->w.root->fn_sernum;
2016 INIT_LIST_HEAD(&iter->w.lh);
2017 fib6_walker_link(net, &iter->w);
2020 static struct fib6_table *ipv6_route_seq_next_table(struct fib6_table *tbl,
2024 struct hlist_node *node;
2027 h = (tbl->tb6_id & (FIB6_TABLE_HASHSZ - 1)) + 1;
2028 node = rcu_dereference_bh(hlist_next_rcu(&tbl->tb6_hlist));
2034 while (!node && h < FIB6_TABLE_HASHSZ) {
2035 node = rcu_dereference_bh(
2036 hlist_first_rcu(&net->ipv6.fib_table_hash[h++]));
2038 return hlist_entry_safe(node, struct fib6_table, tb6_hlist);
2041 static void ipv6_route_check_sernum(struct ipv6_route_iter *iter)
2043 if (iter->sernum != iter->w.root->fn_sernum) {
2044 iter->sernum = iter->w.root->fn_sernum;
2045 iter->w.state = FWS_INIT;
2046 iter->w.node = iter->w.root;
2047 WARN_ON(iter->w.skip);
2048 iter->w.skip = iter->w.count;
2052 static void *ipv6_route_seq_next(struct seq_file *seq, void *v, loff_t *pos)
2056 struct net *net = seq_file_net(seq);
2057 struct ipv6_route_iter *iter = seq->private;
2062 n = ((struct rt6_info *)v)->dst.rt6_next;
2069 ipv6_route_check_sernum(iter);
2070 read_lock(&iter->tbl->tb6_lock);
2071 r = fib6_walk_continue(&iter->w);
2072 read_unlock(&iter->tbl->tb6_lock);
2076 return iter->w.leaf;
2078 fib6_walker_unlink(net, &iter->w);
2081 fib6_walker_unlink(net, &iter->w);
2083 iter->tbl = ipv6_route_seq_next_table(iter->tbl, net);
2087 ipv6_route_seq_setup_walk(iter, net);
2091 static void *ipv6_route_seq_start(struct seq_file *seq, loff_t *pos)
2094 struct net *net = seq_file_net(seq);
2095 struct ipv6_route_iter *iter = seq->private;
2098 iter->tbl = ipv6_route_seq_next_table(NULL, net);
2102 ipv6_route_seq_setup_walk(iter, net);
2103 return ipv6_route_seq_next(seq, NULL, pos);
2109 static bool ipv6_route_iter_active(struct ipv6_route_iter *iter)
2111 struct fib6_walker *w = &iter->w;
2112 return w->node && !(w->state == FWS_U && w->node == w->root);
2115 static void ipv6_route_seq_stop(struct seq_file *seq, void *v)
2118 struct net *net = seq_file_net(seq);
2119 struct ipv6_route_iter *iter = seq->private;
2121 if (ipv6_route_iter_active(iter))
2122 fib6_walker_unlink(net, &iter->w);
2124 rcu_read_unlock_bh();
2127 static const struct seq_operations ipv6_route_seq_ops = {
2128 .start = ipv6_route_seq_start,
2129 .next = ipv6_route_seq_next,
2130 .stop = ipv6_route_seq_stop,
2131 .show = ipv6_route_seq_show
2134 int ipv6_route_open(struct inode *inode, struct file *file)
2136 return seq_open_net(inode, file, &ipv6_route_seq_ops,
2137 sizeof(struct ipv6_route_iter));
2140 #endif /* CONFIG_PROC_FS */