Commit 3d3ea5af authored by Vlad Yasevich's avatar Vlad Yasevich Committed by David S. Miller
Browse files

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: default avatarVladislav Yasevich <vyasevic@redhat.com>
Acked-by: default avatarDavid Ahern <dsahern@gmail.com>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
parent 34aa83c2

include/linux/rtnetlink.h

+2 −1
Original line number Diff line number Diff line
@@ -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);

include/uapi/linux/if_link.h

+11 −0
Original line number Diff line number Diff line
@@ -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 */

net/core/dev.c

+1 −1
Original line number Diff line number Diff line
@@ -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);



		/*

net/core/rtnetlink.c

+56 −9
Original line number Diff line number Diff line
@@ -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);
@@ -2840,7 +2879,8 @@ 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,

static void rtmsg_ifinfo_event(int type, struct net_device *dev,

			       unsigned int change, u32 event,

			       gfp_t flags)

{

	struct sk_buff *skb;
@@ -2848,10 +2888,16 @@ void rtmsg_ifinfo(int type, struct net_device *dev, unsigned int change, 
	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;

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