From 3d3ea5af5c0b382bc9d9aed378fd814fb5d4a011 Mon Sep 17 00:00:00 2001 From: Vlad Yasevich Date: Sat, 27 May 2017 10:14:34 -0400 Subject: [PATCH] rtnl: Add support for netdev event to link messages When netdev events happen, a rtnetlink_event() handler will send messages for every event in it's white list. These messages contain current information about a particular device, but they do not include the iformation about which event just happened. So, it is impossible to tell what just happend for these events. This patch adds a new extension to RTM_NEWLINK message called IFLA_EVENT that would have an encoding of event that triggered this message. This would allow the the message consumer to easily determine if it needs to perform certain actions. Signed-off-by: Vladislav Yasevich Acked-by: David Ahern Signed-off-by: David S. Miller --- include/linux/rtnetlink.h | 3 +- include/uapi/linux/if_link.h | 11 ++++++ net/core/dev.c | 2 +- net/core/rtnetlink.c | 65 +++++++++++++++++++++++++++++++----- 4 files changed, 70 insertions(+), 11 deletions(-) diff --git a/include/linux/rtnetlink.h b/include/linux/rtnetlink.h index 57e54847b0b9..dea59c8eec54 100644 --- a/include/linux/rtnetlink.h +++ b/include/linux/rtnetlink.h @@ -18,7 +18,8 @@ extern int rtnl_put_cacheinfo(struct sk_buff *skb, struct dst_entry *dst, void rtmsg_ifinfo(int type, struct net_device *dev, unsigned change, gfp_t flags); struct sk_buff *rtmsg_ifinfo_build_skb(int type, struct net_device *dev, - unsigned change, gfp_t flags); + unsigned change, u32 event, + gfp_t flags); void rtmsg_ifinfo_send(struct sk_buff *skb, struct net_device *dev, gfp_t flags); diff --git a/include/uapi/linux/if_link.h b/include/uapi/linux/if_link.h index 15ac20382aba..8ed679fe603f 100644 --- a/include/uapi/linux/if_link.h +++ b/include/uapi/linux/if_link.h @@ -157,6 +157,7 @@ enum { IFLA_GSO_MAX_SIZE, IFLA_PAD, IFLA_XDP, + IFLA_EVENT, __IFLA_MAX }; @@ -911,4 +912,14 @@ enum { #define IFLA_XDP_MAX (__IFLA_XDP_MAX - 1) +enum { + IFLA_EVENT_NONE, + IFLA_EVENT_REBOOT, /* internal reset / reboot */ + IFLA_EVENT_FEATURES, /* change in offload features */ + IFLA_EVENT_BONDING_FAILOVER, /* change in active slave */ + IFLA_EVENT_NOTIFY_PEERS, /* re-sent grat. arp/ndisc */ + IFLA_EVENT_IGMP_RESEND, /* re-sent IGMP JOIN */ + IFLA_EVENT_BONDING_OPTIONS, /* change in bonding options */ +}; + #endif /* _UAPI_LINUX_IF_LINK_H */ diff --git a/net/core/dev.c b/net/core/dev.c index 3d98fbf4cbb0..06e0a7492df8 100644 --- a/net/core/dev.c +++ b/net/core/dev.c @@ -7084,7 +7084,7 @@ static void rollback_registered_many(struct list_head *head) if (!dev->rtnl_link_ops || dev->rtnl_link_state == RTNL_LINK_INITIALIZED) - skb = rtmsg_ifinfo_build_skb(RTM_DELLINK, dev, ~0U, + skb = rtmsg_ifinfo_build_skb(RTM_DELLINK, dev, ~0U, 0, GFP_KERNEL); /* diff --git a/net/core/rtnetlink.c b/net/core/rtnetlink.c index 64953af4a3b1..9da53e43750c 100644 --- a/net/core/rtnetlink.c +++ b/net/core/rtnetlink.c @@ -941,6 +941,7 @@ static noinline size_t if_nlmsg_size(const struct net_device *dev, + nla_total_size(MAX_PHYS_ITEM_ID_LEN) /* IFLA_PHYS_SWITCH_ID */ + nla_total_size(IFNAMSIZ) /* IFLA_PHYS_PORT_NAME */ + rtnl_xdp_size() /* IFLA_XDP */ + + nla_total_size(4) /* IFLA_EVENT */ + nla_total_size(1); /* IFLA_PROTO_DOWN */ } @@ -1282,9 +1283,40 @@ err_cancel: return err; } +static u32 rtnl_get_event(unsigned long event) +{ + u32 rtnl_event_type = IFLA_EVENT_NONE; + + switch (event) { + case NETDEV_REBOOT: + rtnl_event_type = IFLA_EVENT_REBOOT; + break; + case NETDEV_FEAT_CHANGE: + rtnl_event_type = IFLA_EVENT_FEATURES; + break; + case NETDEV_BONDING_FAILOVER: + rtnl_event_type = IFLA_EVENT_BONDING_FAILOVER; + break; + case NETDEV_NOTIFY_PEERS: + rtnl_event_type = IFLA_EVENT_NOTIFY_PEERS; + break; + case NETDEV_RESEND_IGMP: + rtnl_event_type = IFLA_EVENT_IGMP_RESEND; + break; + case NETDEV_CHANGEINFODATA: + rtnl_event_type = IFLA_EVENT_BONDING_OPTIONS; + break; + default: + break; + } + + return rtnl_event_type; +} + static int rtnl_fill_ifinfo(struct sk_buff *skb, struct net_device *dev, int type, u32 pid, u32 seq, u32 change, - unsigned int flags, u32 ext_filter_mask) + unsigned int flags, u32 ext_filter_mask, + u32 event) { struct ifinfomsg *ifm; struct nlmsghdr *nlh; @@ -1333,6 +1365,11 @@ static int rtnl_fill_ifinfo(struct sk_buff *skb, struct net_device *dev, nla_put_u8(skb, IFLA_PROTO_DOWN, dev->proto_down)) goto nla_put_failure; + if (event != IFLA_EVENT_NONE) { + if (nla_put_u32(skb, IFLA_EVENT, event)) + goto nla_put_failure; + } + if (rtnl_fill_link_ifmap(skb, dev)) goto nla_put_failure; @@ -1467,6 +1504,7 @@ static const struct nla_policy ifla_policy[IFLA_MAX+1] = { [IFLA_LINK_NETNSID] = { .type = NLA_S32 }, [IFLA_PROTO_DOWN] = { .type = NLA_U8 }, [IFLA_XDP] = { .type = NLA_NESTED }, + [IFLA_EVENT] = { .type = NLA_U32 }, }; static const struct nla_policy ifla_info_policy[IFLA_INFO_MAX+1] = { @@ -1626,7 +1664,7 @@ static int rtnl_dump_ifinfo(struct sk_buff *skb, struct netlink_callback *cb) NETLINK_CB(cb->skb).portid, cb->nlh->nlmsg_seq, 0, flags, - ext_filter_mask); + ext_filter_mask, 0); if (err < 0) { if (likely(skb->len)) @@ -2736,7 +2774,7 @@ static int rtnl_getlink(struct sk_buff *skb, struct nlmsghdr *nlh, return -ENOBUFS; err = rtnl_fill_ifinfo(nskb, dev, RTM_NEWLINK, NETLINK_CB(skb).portid, - nlh->nlmsg_seq, 0, 0, ext_filter_mask); + nlh->nlmsg_seq, 0, 0, ext_filter_mask, 0); if (err < 0) { /* -EMSGSIZE implies BUG in if_nlmsg_size */ WARN_ON(err == -EMSGSIZE); @@ -2808,7 +2846,8 @@ static int rtnl_dump_all(struct sk_buff *skb, struct netlink_callback *cb) } struct sk_buff *rtmsg_ifinfo_build_skb(int type, struct net_device *dev, - unsigned int change, gfp_t flags) + unsigned int change, + u32 event, gfp_t flags) { struct net *net = dev_net(dev); struct sk_buff *skb; @@ -2819,7 +2858,7 @@ struct sk_buff *rtmsg_ifinfo_build_skb(int type, struct net_device *dev, if (skb == NULL) goto errout; - err = rtnl_fill_ifinfo(skb, dev, type, 0, 0, change, 0, 0); + err = rtnl_fill_ifinfo(skb, dev, type, 0, 0, change, 0, 0, event); if (err < 0) { /* -EMSGSIZE implies BUG in if_nlmsg_size() */ WARN_ON(err == -EMSGSIZE); @@ -2840,18 +2879,25 @@ void rtmsg_ifinfo_send(struct sk_buff *skb, struct net_device *dev, gfp_t flags) rtnl_notify(skb, net, 0, RTNLGRP_LINK, NULL, flags); } -void rtmsg_ifinfo(int type, struct net_device *dev, unsigned int change, - gfp_t flags) +static void rtmsg_ifinfo_event(int type, struct net_device *dev, + unsigned int change, u32 event, + gfp_t flags) { struct sk_buff *skb; if (dev->reg_state != NETREG_REGISTERED) return; - skb = rtmsg_ifinfo_build_skb(type, dev, change, flags); + skb = rtmsg_ifinfo_build_skb(type, dev, change, event, flags); if (skb) rtmsg_ifinfo_send(skb, dev, flags); } + +void rtmsg_ifinfo(int type, struct net_device *dev, unsigned int change, + gfp_t flags) +{ + rtmsg_ifinfo_event(type, dev, change, IFLA_EVENT_NONE, flags); +} EXPORT_SYMBOL(rtmsg_ifinfo); static int nlmsg_populate_fdb_fill(struct sk_buff *skb, @@ -4168,7 +4214,8 @@ static int rtnetlink_event(struct notifier_block *this, unsigned long event, voi case NETDEV_NOTIFY_PEERS: case NETDEV_RESEND_IGMP: case NETDEV_CHANGEINFODATA: - rtmsg_ifinfo(RTM_NEWLINK, dev, 0, GFP_KERNEL); + rtmsg_ifinfo_event(RTM_NEWLINK, dev, 0, rtnl_get_event(event), + GFP_KERNEL); break; default: break; -- 2.20.1