From 1c9cac65cecd4f98d8713ec0c737c38a26e5b5c2 Mon Sep 17 00:00:00 2001 From: Ido Schimmel Date: Wed, 4 Nov 2020 15:30:23 +0200 Subject: nexthop: Add nexthop notification data structures Add data structures that will be used for nexthop replace and delete notifications in the previously introduced nexthop notification chain. New data structures are added instead of passing the existing nexthop code structures directly for several reasons. First, the existing structures encode a lot of bookkeeping information which is irrelevant for listeners of the notification chain. Second, the existing structures can be changed without worrying about introducing regressions in listeners since they are not accessed directly by them. Third, listeners of the notification chain do not need to each parse the relatively complex nexthop code structures. They are passing the required information in a simplified way. Note that a single 'has_encap' bit is added instead of the actual encapsulation information since current listeners do not support such nexthops. Changes since RFC: * s/is_encap/has_encap/ Signed-off-by: Ido Schimmel Reviewed-by: David Ahern Signed-off-by: Jakub Kicinski --- include/net/nexthop.h | 35 +++++++++++++++++++++++++++++++++++ 1 file changed, 35 insertions(+) (limited to 'include') diff --git a/include/net/nexthop.h b/include/net/nexthop.h index 2fd76a9b6dc8..4a17b040b502 100644 --- a/include/net/nexthop.h +++ b/include/net/nexthop.h @@ -108,6 +108,41 @@ enum nexthop_event_type { NEXTHOP_EVENT_DEL }; +struct nh_notifier_single_info { + struct net_device *dev; + u8 gw_family; + union { + __be32 ipv4; + struct in6_addr ipv6; + }; + u8 is_reject:1, + is_fdb:1, + has_encap:1; +}; + +struct nh_notifier_grp_entry_info { + u8 weight; + u32 id; + struct nh_notifier_single_info nh; +}; + +struct nh_notifier_grp_info { + u16 num_nh; + bool is_fdb; + struct nh_notifier_grp_entry_info nh_entries[]; +}; + +struct nh_notifier_info { + struct net *net; + struct netlink_ext_ack *extack; + u32 id; + bool is_grp; + union { + struct nh_notifier_single_info *nh; + struct nh_notifier_grp_info *nh_grp; + }; +}; + int register_nexthop_notifier(struct net *net, struct notifier_block *nb); int unregister_nexthop_notifier(struct net *net, struct notifier_block *nb); -- cgit From 968a83f8cf6fd5a107289c57ee3197a52c72f02c Mon Sep 17 00:00:00 2001 From: Ido Schimmel Date: Wed, 4 Nov 2020 15:30:27 +0200 Subject: rtnetlink: Add RTNH_F_TRAP flag The flag indicates to user space that the nexthop is not programmed to forward packets in hardware, but rather to trap them to the CPU. This is needed, for example, when the MAC of the nexthop neighbour is not resolved and packets should reach the CPU to trigger neighbour resolution. The flag will be used in subsequent patches by netdevsim to test nexthop objects programming to device drivers and in the future by mlxsw as well. Changes since RFC: * Reword commit message Signed-off-by: Ido Schimmel Reviewed-by: David Ahern Signed-off-by: Jakub Kicinski --- include/uapi/linux/rtnetlink.h | 6 ++++-- net/ipv4/fib_semantics.c | 2 ++ 2 files changed, 6 insertions(+), 2 deletions(-) (limited to 'include') diff --git a/include/uapi/linux/rtnetlink.h b/include/uapi/linux/rtnetlink.h index d1325ffb0060..2ffbef5da6c1 100644 --- a/include/uapi/linux/rtnetlink.h +++ b/include/uapi/linux/rtnetlink.h @@ -396,11 +396,13 @@ struct rtnexthop { #define RTNH_F_DEAD 1 /* Nexthop is dead (used by multipath) */ #define RTNH_F_PERVASIVE 2 /* Do recursive gateway lookup */ #define RTNH_F_ONLINK 4 /* Gateway is forced on link */ -#define RTNH_F_OFFLOAD 8 /* offloaded route */ +#define RTNH_F_OFFLOAD 8 /* Nexthop is offloaded */ #define RTNH_F_LINKDOWN 16 /* carrier-down on nexthop */ #define RTNH_F_UNRESOLVED 32 /* The entry is unresolved (ipmr) */ +#define RTNH_F_TRAP 64 /* Nexthop is trapping packets */ -#define RTNH_COMPARE_MASK (RTNH_F_DEAD | RTNH_F_LINKDOWN | RTNH_F_OFFLOAD) +#define RTNH_COMPARE_MASK (RTNH_F_DEAD | RTNH_F_LINKDOWN | \ + RTNH_F_OFFLOAD | RTNH_F_TRAP) /* Macros to handle hexthops */ diff --git a/net/ipv4/fib_semantics.c b/net/ipv4/fib_semantics.c index 1f75dc686b6b..f70b9a0c4957 100644 --- a/net/ipv4/fib_semantics.c +++ b/net/ipv4/fib_semantics.c @@ -1644,6 +1644,8 @@ int fib_nexthop_info(struct sk_buff *skb, const struct fib_nh_common *nhc, *flags |= (nhc->nhc_flags & RTNH_F_ONLINK); if (nhc->nhc_flags & RTNH_F_OFFLOAD) *flags |= RTNH_F_OFFLOAD; + if (nhc->nhc_flags & RTNH_F_TRAP) + *flags |= RTNH_F_TRAP; if (!skip_oif && nhc->nhc_dev && nla_put_u32(skb, RTA_OIF, nhc->nhc_dev->ifindex)) -- cgit From e95f2592f633a334b175003f13f42d3c217dc657 Mon Sep 17 00:00:00 2001 From: Ido Schimmel Date: Wed, 4 Nov 2020 15:30:28 +0200 Subject: nexthop: Allow setting "offload" and "trap" indications on nexthops Add a function that can be called by device drivers to set "offload" or "trap" indication on nexthops following nexthop notifications. Changes since RFC: * s/nexthop_hw_flags_set/nexthop_set_hw_flags/ Signed-off-by: Ido Schimmel Signed-off-by: Jakub Kicinski --- include/net/nexthop.h | 1 + net/ipv4/nexthop.c | 21 +++++++++++++++++++++ 2 files changed, 22 insertions(+) (limited to 'include') diff --git a/include/net/nexthop.h b/include/net/nexthop.h index 4a17b040b502..aa7ac12c35e2 100644 --- a/include/net/nexthop.h +++ b/include/net/nexthop.h @@ -145,6 +145,7 @@ struct nh_notifier_info { int register_nexthop_notifier(struct net *net, struct notifier_block *nb); int unregister_nexthop_notifier(struct net *net, struct notifier_block *nb); +void nexthop_set_hw_flags(struct net *net, u32 id, bool offload, bool trap); /* caller is holding rcu or rtnl; no reference taken to nexthop */ struct nexthop *nexthop_find_by_id(struct net *net, u32 id); diff --git a/net/ipv4/nexthop.c b/net/ipv4/nexthop.c index 1d66f2439063..d1a1600aee18 100644 --- a/net/ipv4/nexthop.c +++ b/net/ipv4/nexthop.c @@ -2081,6 +2081,27 @@ int unregister_nexthop_notifier(struct net *net, struct notifier_block *nb) } EXPORT_SYMBOL(unregister_nexthop_notifier); +void nexthop_set_hw_flags(struct net *net, u32 id, bool offload, bool trap) +{ + struct nexthop *nexthop; + + rcu_read_lock(); + + nexthop = nexthop_find_by_id(net, id); + if (!nexthop) + goto out; + + nexthop->nh_flags &= ~(RTNH_F_OFFLOAD | RTNH_F_TRAP); + if (offload) + nexthop->nh_flags |= RTNH_F_OFFLOAD; + if (trap) + nexthop->nh_flags |= RTNH_F_TRAP; + +out: + rcu_read_unlock(); +} +EXPORT_SYMBOL(nexthop_set_hw_flags); + static void __net_exit nexthop_net_exit(struct net *net) { rtnl_lock(); -- cgit From 732d167bf5f53a8c1e8c53cf7dbffe2a13f63752 Mon Sep 17 00:00:00 2001 From: Ido Schimmel Date: Wed, 4 Nov 2020 15:30:29 +0200 Subject: nexthop: Emit a notification when a nexthop is added Emit a notification in the nexthop notification chain when a new nexthop is added (not replaced). The nexthop can either be a new group or a single nexthop. The notification is sent after the nexthop is inserted into the red-black tree, as listeners might need to callback into the nexthop code with the nexthop ID in order to mark the nexthop as offloaded. A 'REPLACE' notification is emitted instead of 'ADD' as the distinction between the two is not important for in-kernel listeners. In case the listener is not familiar with the encoded nexthop ID, it can simply treat it as a new one. This is also consistent with the route offload API. Changes since RFC: * Reword commit message Signed-off-by: Ido Schimmel Signed-off-by: Jakub Kicinski --- include/net/nexthop.h | 3 ++- net/ipv4/nexthop.c | 6 +++++- 2 files changed, 7 insertions(+), 2 deletions(-) (limited to 'include') diff --git a/include/net/nexthop.h b/include/net/nexthop.h index aa7ac12c35e2..9c85199b826e 100644 --- a/include/net/nexthop.h +++ b/include/net/nexthop.h @@ -105,7 +105,8 @@ struct nexthop { }; enum nexthop_event_type { - NEXTHOP_EVENT_DEL + NEXTHOP_EVENT_DEL, + NEXTHOP_EVENT_REPLACE, }; struct nh_notifier_single_info { diff --git a/net/ipv4/nexthop.c b/net/ipv4/nexthop.c index d1a1600aee18..4e9d0395f959 100644 --- a/net/ipv4/nexthop.c +++ b/net/ipv4/nexthop.c @@ -1278,7 +1278,11 @@ static int insert_nexthop(struct net *net, struct nexthop *new_nh, rb_link_node_rcu(&new_nh->rb_node, parent, pp); rb_insert_color(&new_nh->rb_node, root); - rc = 0; + + rc = call_nexthop_notifiers(net, NEXTHOP_EVENT_REPLACE, new_nh, extack); + if (rc) + rb_erase(&new_nh->rb_node, &net->nexthop.rb_root); + out: if (!rc) { nh_base_seq_inc(net); -- cgit From ce7e9c8a080b6daca646a7740d916ed547503a12 Mon Sep 17 00:00:00 2001 From: Ido Schimmel Date: Wed, 4 Nov 2020 15:30:34 +0200 Subject: nexthop: Pass extack to register_nexthop_notifier() This will be used by the next patch which extends the function to replay all the existing nexthops to the notifier block being registered. Device drivers will be able to pass extack to the function since it is passed to them upon reload from devlink. Signed-off-by: Ido Schimmel Reviewed-by: David Ahern Signed-off-by: Jakub Kicinski --- drivers/net/vxlan.c | 3 ++- include/net/nexthop.h | 3 ++- net/ipv4/nexthop.c | 3 ++- 3 files changed, 6 insertions(+), 3 deletions(-) (limited to 'include') diff --git a/drivers/net/vxlan.c b/drivers/net/vxlan.c index b9db20b4ebfd..183e708dc6cb 100644 --- a/drivers/net/vxlan.c +++ b/drivers/net/vxlan.c @@ -4711,7 +4711,8 @@ static __net_init int vxlan_init_net(struct net *net) for (h = 0; h < PORT_HASH_SIZE; ++h) INIT_HLIST_HEAD(&vn->sock_list[h]); - return register_nexthop_notifier(net, &vn->nexthop_notifier_block); + return register_nexthop_notifier(net, &vn->nexthop_notifier_block, + NULL); } static void vxlan_destroy_tunnels(struct net *net, struct list_head *head) diff --git a/include/net/nexthop.h b/include/net/nexthop.h index 9c85199b826e..226930d66b63 100644 --- a/include/net/nexthop.h +++ b/include/net/nexthop.h @@ -144,7 +144,8 @@ struct nh_notifier_info { }; }; -int register_nexthop_notifier(struct net *net, struct notifier_block *nb); +int register_nexthop_notifier(struct net *net, struct notifier_block *nb, + struct netlink_ext_ack *extack); int unregister_nexthop_notifier(struct net *net, struct notifier_block *nb); void nexthop_set_hw_flags(struct net *net, u32 id, bool offload, bool trap); diff --git a/net/ipv4/nexthop.c b/net/ipv4/nexthop.c index d5a2c28bea49..9a235d5c5670 100644 --- a/net/ipv4/nexthop.c +++ b/net/ipv4/nexthop.c @@ -2118,7 +2118,8 @@ static struct notifier_block nh_netdev_notifier = { .notifier_call = nh_netdev_event, }; -int register_nexthop_notifier(struct net *net, struct notifier_block *nb) +int register_nexthop_notifier(struct net *net, struct notifier_block *nb, + struct netlink_ext_ack *extack) { return blocking_notifier_chain_register(&net->nexthop.notifier_chain, nb); -- cgit