From 7d61588f690def55ba2885f7f4b03d13ff45b163 Mon Sep 17 00:00:00 2001 From: Ido Schimmel Date: Tue, 15 Sep 2020 14:40:59 +0300 Subject: [PATCH 1/5] nexthop: Remove unused function declaration from header file Not used or implemented anywhere. Signed-off-by: Ido Schimmel Reviewed-by: David Ahern Signed-off-by: David S. Miller --- include/net/nexthop.h | 3 --- 1 file changed, 3 deletions(-) diff --git a/include/net/nexthop.h b/include/net/nexthop.h index 3a4f9e3b91a55..2e44efe5709be 100644 --- a/include/net/nexthop.h +++ b/include/net/nexthop.h @@ -109,9 +109,6 @@ enum nexthop_event_type { 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); From 52f7232a790a36da30eb64c6de6067a9e4ad194c Mon Sep 17 00:00:00 2001 From: Ido Schimmel Date: Tue, 15 Sep 2020 14:41:00 +0300 Subject: [PATCH 2/5] nexthop: Remove NEXTHOP_EVENT_ADD Not used anywhere. Signed-off-by: Ido Schimmel Suggested-by: David Ahern Signed-off-by: David S. Miller --- include/net/nexthop.h | 1 - 1 file changed, 1 deletion(-) diff --git a/include/net/nexthop.h b/include/net/nexthop.h index 2e44efe5709be..2fd76a9b6dc8b 100644 --- a/include/net/nexthop.h +++ b/include/net/nexthop.h @@ -105,7 +105,6 @@ struct nexthop { }; enum nexthop_event_type { - NEXTHOP_EVENT_ADD, NEXTHOP_EVENT_DEL }; From 80690ec6b595807db9a52ec5b225a2d88033ddb5 Mon Sep 17 00:00:00 2001 From: Ido Schimmel Date: Tue, 15 Sep 2020 14:41:01 +0300 Subject: [PATCH 3/5] nexthop: Convert to blocking notification chain Currently, the only listener of the nexthop notification chain is the VXLAN driver. Subsequent patches will add more listeners (e.g., device drivers such as netdevsim) that need to be able to block when processing notifications. Therefore, convert the notification chain to a blocking one. This is safe as notifications are always emitted from process context. Signed-off-by: Ido Schimmel Reviewed-by: David Ahern Signed-off-by: David S. Miller --- include/net/netns/nexthop.h | 2 +- net/ipv4/nexthop.c | 13 +++++++------ 2 files changed, 8 insertions(+), 7 deletions(-) diff --git a/include/net/netns/nexthop.h b/include/net/netns/nexthop.h index 1937476c94a0e..1849e77eb68ab 100644 --- a/include/net/netns/nexthop.h +++ b/include/net/netns/nexthop.h @@ -14,6 +14,6 @@ struct netns_nexthop { unsigned int seq; /* protected by rtnl_mutex */ u32 last_id_allocated; - struct atomic_notifier_head notifier_chain; + struct blocking_notifier_head notifier_chain; }; #endif diff --git a/net/ipv4/nexthop.c b/net/ipv4/nexthop.c index bf9d4cd2d6e58..13d9219a9aa1e 100644 --- a/net/ipv4/nexthop.c +++ b/net/ipv4/nexthop.c @@ -42,8 +42,8 @@ static int call_nexthop_notifiers(struct net *net, { int err; - err = atomic_notifier_call_chain(&net->nexthop.notifier_chain, - event_type, nh); + err = blocking_notifier_call_chain(&net->nexthop.notifier_chain, + event_type, nh); return notifier_to_errno(err); } @@ -1959,14 +1959,15 @@ static struct notifier_block nh_netdev_notifier = { int register_nexthop_notifier(struct net *net, struct notifier_block *nb) { - return atomic_notifier_chain_register(&net->nexthop.notifier_chain, nb); + return blocking_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); + return blocking_notifier_chain_unregister(&net->nexthop.notifier_chain, + nb); } EXPORT_SYMBOL(unregister_nexthop_notifier); @@ -1986,7 +1987,7 @@ 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); + BLOCKING_INIT_NOTIFIER_HEAD(&net->nexthop.notifier_chain); return 0; } From 0695564bb4a24440b38b46bf52465a93a0ca1974 Mon Sep 17 00:00:00 2001 From: Ido Schimmel Date: Tue, 15 Sep 2020 14:41:02 +0300 Subject: [PATCH 4/5] nexthop: Only emit a notification when nexthop is actually deleted Currently, the in-kernel delete notification is emitted from the error path of nexthop_add() and replace_nexthop(), which can be confusing to in-kernel listeners as they are not familiar with the nexthop. Instead, only emit the notification when the nexthop is actually deleted. The following sub-cases are covered: 1. User space deletes the nexthop 2. The nexthop is deleted by the kernel due to a netdev event (e.g., nexthop device going down) 3. A group is deleted because its last nexthop is being deleted 4. The network namespace of the nexthop device is deleted Signed-off-by: Ido Schimmel Reviewed-by: David Ahern Signed-off-by: David S. Miller --- net/ipv4/nexthop.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/net/ipv4/nexthop.c b/net/ipv4/nexthop.c index 13d9219a9aa1e..8c0f17c6863cf 100644 --- a/net/ipv4/nexthop.c +++ b/net/ipv4/nexthop.c @@ -870,8 +870,6 @@ 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; @@ -909,6 +907,8 @@ static void __remove_nexthop(struct net *net, struct nexthop *nh, static void remove_nexthop(struct net *net, struct nexthop *nh, struct nl_info *nlinfo) { + call_nexthop_notifiers(net, NEXTHOP_EVENT_DEL, nh); + /* remove from the tree */ rb_erase(&nh->rb_node, &net->nexthop.rb_root); From 7a5e9d84f9e436035f44310511efdddb6e497996 Mon Sep 17 00:00:00 2001 From: Ido Schimmel Date: Tue, 15 Sep 2020 14:41:03 +0300 Subject: [PATCH 5/5] selftests: fib_nexthops: Test cleanup of FDB entries following nexthop deletion Commit c7cdbe2efc40 ("vxlan: support for nexthop notifiers") registered a listener in the VXLAN driver to the nexthop notification chain. Its purpose is to cleanup FDB entries that use a nexthop that is being deleted. Test that such FDB entries are removed when the nexthop group that they use is deleted. Test that entries are not deleted when a single nexthop in the group is deleted. Signed-off-by: Ido Schimmel Reviewed-by: David Ahern Signed-off-by: David S. Miller --- tools/testing/selftests/net/fib_nexthops.sh | 14 ++++++++++++++ 1 file changed, 14 insertions(+) diff --git a/tools/testing/selftests/net/fib_nexthops.sh b/tools/testing/selftests/net/fib_nexthops.sh index b74884d529136..eb693a3b7b4a1 100755 --- a/tools/testing/selftests/net/fib_nexthops.sh +++ b/tools/testing/selftests/net/fib_nexthops.sh @@ -411,9 +411,16 @@ ipv6_fdb_grp_fcnal() run_cmd "$IP -6 ro add 2001:db8:101::1/128 nhid 103" log_test $? 2 "Route add with fdb nexthop group" + run_cmd "$IP nexthop del id 61" + run_cmd "$BRIDGE fdb get to 02:02:00:00:00:13 dev vx10 self" + log_test $? 0 "Fdb entry after deleting a single nexthop" + run_cmd "$IP nexthop del id 102" log_test $? 0 "Fdb nexthop delete" + run_cmd "$BRIDGE fdb get to 02:02:00:00:00:13 dev vx10 self" + log_test $? 254 "Fdb entry after deleting a nexthop group" + $IP link del dev vx10 } @@ -484,9 +491,16 @@ ipv4_fdb_grp_fcnal() run_cmd "$IP ro add 172.16.0.0/22 nhid 103" log_test $? 2 "Route add with fdb nexthop group" + run_cmd "$IP nexthop del id 12" + run_cmd "$BRIDGE fdb get to 02:02:00:00:00:13 dev vx10 self" + log_test $? 0 "Fdb entry after deleting a single nexthop" + run_cmd "$IP nexthop del id 102" log_test $? 0 "Fdb nexthop delete" + run_cmd "$BRIDGE fdb get to 02:02:00:00:00:13 dev vx10 self" + log_test $? 254 "Fdb entry after deleting a nexthop group" + $IP link del dev vx10 }