diff options
Diffstat (limited to 'net/ipv6/ip6_fib.c')
-rw-r--r-- | net/ipv6/ip6_fib.c | 197 |
1 files changed, 162 insertions, 35 deletions
diff --git a/net/ipv6/ip6_fib.c b/net/ipv6/ip6_fib.c index ebb299c..a3b5c16 100644 --- a/net/ipv6/ip6_fib.c +++ b/net/ipv6/ip6_fib.c @@ -33,6 +33,7 @@ #include <net/ndisc.h> #include <net/addrconf.h> #include <net/lwtunnel.h> +#include <net/fib_notifier.h> #include <net/ip6_fib.h> #include <net/ip6_route.h> @@ -148,12 +149,24 @@ static struct fib6_node *node_alloc(void) return fn; } -static void node_free(struct fib6_node *fn) +static void node_free_immediate(struct fib6_node *fn) +{ + kmem_cache_free(fib6_node_kmem, fn); +} + +static void node_free_rcu(struct rcu_head *head) { + struct fib6_node *fn = container_of(head, struct fib6_node, rcu); + kmem_cache_free(fib6_node_kmem, fn); } -static void rt6_free_pcpu(struct rt6_info *non_pcpu_rt) +static void node_free(struct fib6_node *fn) +{ + call_rcu(&fn->rcu, node_free_rcu); +} + +void rt6_free_pcpu(struct rt6_info *non_pcpu_rt) { int cpu; @@ -176,15 +189,7 @@ static void rt6_free_pcpu(struct rt6_info *non_pcpu_rt) free_percpu(non_pcpu_rt->rt6i_pcpu); non_pcpu_rt->rt6i_pcpu = NULL; } - -static void rt6_release(struct rt6_info *rt) -{ - if (atomic_dec_and_test(&rt->rt6i_ref)) { - rt6_free_pcpu(rt); - dst_dev_put(&rt->dst); - dst_release(&rt->dst); - } -} +EXPORT_SYMBOL_GPL(rt6_free_pcpu); static void fib6_link_table(struct net *net, struct fib6_table *tb) { @@ -302,6 +307,109 @@ static void __net_init fib6_tables_init(struct net *net) #endif +unsigned int fib6_tables_seq_read(struct net *net) +{ + unsigned int h, fib_seq = 0; + + rcu_read_lock(); + for (h = 0; h < FIB6_TABLE_HASHSZ; h++) { + struct hlist_head *head = &net->ipv6.fib_table_hash[h]; + struct fib6_table *tb; + + hlist_for_each_entry_rcu(tb, head, tb6_hlist) { + read_lock_bh(&tb->tb6_lock); + fib_seq += tb->fib_seq; + read_unlock_bh(&tb->tb6_lock); + } + } + rcu_read_unlock(); + + return fib_seq; +} + +static int call_fib6_entry_notifier(struct notifier_block *nb, struct net *net, + enum fib_event_type event_type, + struct rt6_info *rt) +{ + struct fib6_entry_notifier_info info = { + .rt = rt, + }; + + return call_fib6_notifier(nb, net, event_type, &info.info); +} + +static int call_fib6_entry_notifiers(struct net *net, + enum fib_event_type event_type, + struct rt6_info *rt) +{ + struct fib6_entry_notifier_info info = { + .rt = rt, + }; + + rt->rt6i_table->fib_seq++; + return call_fib6_notifiers(net, event_type, &info.info); +} + +struct fib6_dump_arg { + struct net *net; + struct notifier_block *nb; +}; + +static void fib6_rt_dump(struct rt6_info *rt, struct fib6_dump_arg *arg) +{ + if (rt == arg->net->ipv6.ip6_null_entry) + return; + call_fib6_entry_notifier(arg->nb, arg->net, FIB_EVENT_ENTRY_ADD, rt); +} + +static int fib6_node_dump(struct fib6_walker *w) +{ + struct rt6_info *rt; + + for (rt = w->leaf; rt; rt = rt->dst.rt6_next) + fib6_rt_dump(rt, w->args); + w->leaf = NULL; + return 0; +} + +static void fib6_table_dump(struct net *net, struct fib6_table *tb, + struct fib6_walker *w) +{ + w->root = &tb->tb6_root; + read_lock_bh(&tb->tb6_lock); + fib6_walk(net, w); + read_unlock_bh(&tb->tb6_lock); +} + +/* Called with rcu_read_lock() */ +int fib6_tables_dump(struct net *net, struct notifier_block *nb) +{ + struct fib6_dump_arg arg; + struct fib6_walker *w; + unsigned int h; + + w = kzalloc(sizeof(*w), GFP_ATOMIC); + if (!w) + return -ENOMEM; + + w->func = fib6_node_dump; + arg.net = net; + arg.nb = nb; + w->args = &arg; + + for (h = 0; h < FIB6_TABLE_HASHSZ; h++) { + struct hlist_head *head = &net->ipv6.fib_table_hash[h]; + struct fib6_table *tb; + + hlist_for_each_entry_rcu(tb, head, tb6_hlist) + fib6_table_dump(net, tb, w); + } + + kfree(w); + + return 0; +} + static int fib6_dump_node(struct fib6_walker *w) { int res; @@ -601,9 +709,9 @@ insert_above: if (!in || !ln) { if (in) - node_free(in); + node_free_immediate(in); if (ln) - node_free(ln); + node_free_immediate(ln); return ERR_PTR(-ENOMEM); } @@ -733,8 +841,6 @@ static void fib6_purge_rt(struct rt6_info *rt, struct fib6_node *fn, } fn = fn->parent; } - /* No more references are possible at this point. */ - BUG_ON(atomic_read(&rt->rt6i_ref) != 1); } } @@ -877,8 +983,10 @@ add: rt->dst.rt6_next = iter; *ins = rt; - rt->rt6i_node = fn; + rcu_assign_pointer(rt->rt6i_node, fn); atomic_inc(&rt->rt6i_ref); + call_fib6_entry_notifiers(info->nl_net, FIB_EVENT_ENTRY_ADD, + rt); if (!info->skip_notify) inet6_rt_notify(RTM_NEWROUTE, rt, info, nlflags); info->nl_net->ipv6.rt6_stats->fib_rt_entries++; @@ -903,9 +1011,11 @@ add: return err; *ins = rt; - rt->rt6i_node = fn; + rcu_assign_pointer(rt->rt6i_node, fn); rt->dst.rt6_next = iter->dst.rt6_next; atomic_inc(&rt->rt6i_ref); + call_fib6_entry_notifiers(info->nl_net, FIB_EVENT_ENTRY_REPLACE, + rt); if (!info->skip_notify) inet6_rt_notify(RTM_NEWROUTE, rt, info, NLM_F_REPLACE); if (!(fn->fn_flags & RTN_RTINFO)) { @@ -913,7 +1023,10 @@ add: fn->fn_flags |= RTN_RTINFO; } nsiblings = iter->rt6i_nsiblings; + iter->rt6i_node = NULL; fib6_purge_rt(iter, fn, info->nl_net); + if (fn->rr_ptr == iter) + fn->rr_ptr = NULL; rt6_release(iter); if (nsiblings) { @@ -925,7 +1038,10 @@ add: break; if (rt6_qualify_for_ecmp(iter)) { *ins = iter->dst.rt6_next; + iter->rt6i_node = NULL; fib6_purge_rt(iter, fn, info->nl_net); + if (fn->rr_ptr == iter) + fn->rr_ptr = NULL; rt6_release(iter); nsiblings--; } else { @@ -1014,7 +1130,7 @@ int fib6_add(struct fib6_node *root, struct rt6_info *rt, /* Create subtree root node */ sfn = node_alloc(); if (!sfn) - goto st_failure; + goto failure; sfn->leaf = info->nl_net->ipv6.ip6_null_entry; atomic_inc(&info->nl_net->ipv6.ip6_null_entry->rt6i_ref); @@ -1031,12 +1147,12 @@ int fib6_add(struct fib6_node *root, struct rt6_info *rt, if (IS_ERR(sn)) { /* If it is failed, discard just allocated - root, and then (in st_failure) stale node + root, and then (in failure) stale node in main tree. */ - node_free(sfn); + node_free_immediate(sfn); err = PTR_ERR(sn); - goto st_failure; + goto failure; } /* Now link new subtree to main tree */ @@ -1051,7 +1167,7 @@ int fib6_add(struct fib6_node *root, struct rt6_info *rt, if (IS_ERR(sn)) { err = PTR_ERR(sn); - goto st_failure; + goto failure; } } @@ -1092,18 +1208,17 @@ out: atomic_inc(&pn->leaf->rt6i_ref); } #endif - /* Always release dst as dst->__refcnt is guaranteed - * to be taken before entering this function - */ - dst_release_immediate(&rt->dst); + goto failure; } return err; -#ifdef CONFIG_IPV6_SUBTREES - /* Subtree creation failed, probably main tree node - is orphan. If it is, shoot it. +failure: + /* fn->leaf could be NULL if fn is an intermediate node and we + * failed to add the new route to it in both subtree creation + * failure and fib6_add_rt2node() failure case. + * In both cases, fib6_repair_tree() should be called to fix + * fn->leaf. */ -st_failure: if (fn && !(fn->fn_flags & (RTN_RTINFO|RTN_ROOT))) fib6_repair_tree(info->nl_net, fn); /* Always release dst as dst->__refcnt is guaranteed @@ -1111,7 +1226,6 @@ st_failure: */ dst_release_immediate(&rt->dst); return err; -#endif } /* @@ -1459,6 +1573,7 @@ static void fib6_del_route(struct fib6_node *fn, struct rt6_info **rtp, fib6_purge_rt(rt, fn, net); + call_fib6_entry_notifiers(net, FIB_EVENT_ENTRY_DEL, rt); if (!info->skip_notify) inet6_rt_notify(RTM_DELROUTE, rt, info, 0); rt6_release(rt); @@ -1466,8 +1581,9 @@ static void fib6_del_route(struct fib6_node *fn, struct rt6_info **rtp, int fib6_del(struct rt6_info *rt, struct nl_info *info) { + struct fib6_node *fn = rcu_dereference_protected(rt->rt6i_node, + lockdep_is_held(&rt->rt6i_table->tb6_lock)); struct net *net = info->nl_net; - struct fib6_node *fn = rt->rt6i_node; struct rt6_info **rtp; #if RT6_DEBUG >= 2 @@ -1656,7 +1772,9 @@ static int fib6_clean_node(struct fib6_walker *w) if (res) { #if RT6_DEBUG >= 2 pr_debug("%s: del failed: rt=%p@%p err=%d\n", - __func__, rt, rt->rt6i_node, res); + __func__, rt, + rcu_access_pointer(rt->rt6i_node), + res); #endif continue; } @@ -1778,8 +1896,10 @@ static int fib6_age(struct rt6_info *rt, void *arg) } gc_args->more++; } else if (rt->rt6i_flags & RTF_CACHE) { + if (time_after_eq(now, rt->dst.lastuse + gc_args->timeout)) + rt->dst.obsolete = DST_OBSOLETE_KILL; if (atomic_read(&rt->dst.__refcnt) == 1 && - time_after_eq(now, rt->dst.lastuse + gc_args->timeout)) { + rt->dst.obsolete == DST_OBSOLETE_KILL) { RT6_TRACE("aging clone %p\n", rt); return -1; } else if (rt->rt6i_flags & RTF_GATEWAY) { @@ -1839,6 +1959,11 @@ static void fib6_gc_timer_cb(unsigned long arg) static int __net_init fib6_net_init(struct net *net) { size_t size = sizeof(struct hlist_head) * FIB6_TABLE_HASHSZ; + int err; + + err = fib6_notifier_init(net); + if (err) + return err; spin_lock_init(&net->ipv6.fib6_gc_lock); rwlock_init(&net->ipv6.fib6_walker_lock); @@ -1891,6 +2016,7 @@ out_fib_table_hash: out_rt6_stats: kfree(net->ipv6.rt6_stats); out_timer: + fib6_notifier_exit(net); return -ENOMEM; } @@ -1907,6 +2033,7 @@ static void fib6_net_exit(struct net *net) kfree(net->ipv6.fib6_main_tbl); kfree(net->ipv6.fib_table_hash); kfree(net->ipv6.rt6_stats); + fib6_notifier_exit(net); } static struct pernet_operations fib6_net_ops = { @@ -1930,7 +2057,7 @@ int __init fib6_init(void) goto out_kmem_cache_create; ret = __rtnl_register(PF_INET6, RTM_GETROUTE, NULL, inet6_dump_fib, - NULL); + 0); if (ret) goto out_unregister_subsys; |