From 8590ceedb70181ad9de5a3dc2cfe50ca33a9576a Mon Sep 17 00:00:00 2001 From: Roopa Prabhu Date: Thu, 21 May 2020 22:26:15 -0700 Subject: [PATCH] nexthop: add support for notifiers This patch adds nexthop add/del notifiers. To be used by vxlan driver in a later patch. Could possibly be used by switchdev drivers in the future. Signed-off-by: Roopa Prabhu Signed-off-by: David S. Miller --- include/net/netns/nexthop.h | 1 + include/net/nexthop.h | 12 ++++++++++++ net/ipv4/nexthop.c | 27 +++++++++++++++++++++++++++ 3 files changed, 40 insertions(+) diff --git a/include/net/netns/nexthop.h b/include/net/netns/nexthop.h index c712ee5eebd9..1937476c94a0 100644 --- a/include/net/netns/nexthop.h +++ b/include/net/netns/nexthop.h @@ -14,5 +14,6 @@ struct netns_nexthop { unsigned int seq; /* protected by rtnl_mutex */ u32 last_id_allocated; + struct atomic_notifier_head notifier_chain; }; #endif diff --git a/include/net/nexthop.h b/include/net/nexthop.h index d929c98931ad..4c951680f6f9 100644 --- a/include/net/nexthop.h +++ b/include/net/nexthop.h @@ -10,6 +10,7 @@ #define __LINUX_NEXTHOP_H #include +#include #include #include #include @@ -102,6 +103,17 @@ struct nexthop { }; }; +enum nexthop_event_type { + NEXTHOP_EVENT_ADD, + NEXTHOP_EVENT_DEL +}; + +int call_nexthop_notifier(struct notifier_block *nb, struct net *net, + enum nexthop_event_type event_type, + struct nexthop *nh); +int register_nexthop_notifier(struct net *net, struct notifier_block *nb); +int unregister_nexthop_notifier(struct net *net, struct notifier_block *nb); + /* caller is holding rcu or rtnl; no reference taken to nexthop */ struct nexthop *nexthop_find_by_id(struct net *net, u32 id); void nexthop_free_rcu(struct rcu_head *head); diff --git a/net/ipv4/nexthop.c b/net/ipv4/nexthop.c index bf91edc04631..c337e73e02dd 100644 --- a/net/ipv4/nexthop.c +++ b/net/ipv4/nexthop.c @@ -36,6 +36,17 @@ static const struct nla_policy rtm_nh_policy[NHA_MAX + 1] = { [NHA_FDB] = { .type = NLA_FLAG }, }; +static int call_nexthop_notifiers(struct net *net, + enum fib_event_type event_type, + struct nexthop *nh) +{ + int err; + + err = atomic_notifier_call_chain(&net->nexthop.notifier_chain, + event_type, nh); + return notifier_to_errno(err); +} + static unsigned int nh_dev_hashfn(unsigned int val) { unsigned int mask = NH_DEV_HASHSIZE - 1; @@ -826,6 +837,8 @@ static void __remove_nexthop_fib(struct net *net, struct nexthop *nh) bool do_flush = false; struct fib_info *fi; + call_nexthop_notifiers(net, NEXTHOP_EVENT_DEL, nh); + list_for_each_entry(fi, &nh->fi_list, nh_list) { fi->fib_flags |= RTNH_F_DEAD; do_flush = true; @@ -1865,6 +1878,19 @@ static struct notifier_block nh_netdev_notifier = { .notifier_call = nh_netdev_event, }; +int register_nexthop_notifier(struct net *net, struct notifier_block *nb) +{ + return atomic_notifier_chain_register(&net->nexthop.notifier_chain, nb); +} +EXPORT_SYMBOL(register_nexthop_notifier); + +int unregister_nexthop_notifier(struct net *net, struct notifier_block *nb) +{ + return atomic_notifier_chain_unregister(&net->nexthop.notifier_chain, + nb); +} +EXPORT_SYMBOL(unregister_nexthop_notifier); + static void __net_exit nexthop_net_exit(struct net *net) { rtnl_lock(); @@ -1881,6 +1907,7 @@ static int __net_init nexthop_net_init(struct net *net) net->nexthop.devhash = kzalloc(sz, GFP_KERNEL); if (!net->nexthop.devhash) return -ENOMEM; + ATOMIC_INIT_NOTIFIER_HEAD(&net->nexthop.notifier_chain); return 0; } -- 2.11.0