net: pass info struct via netdevice notifier

So far, only net_device * could be passed along with netdevice notifier
event. This patch provides a possibility to pass custom structure
able to provide info that event listener needs to know.

Signed-off-by: Jiri Pirko <jiri@resnulli.us>

v2->v3: fix typo on simeth
	shortened dev_getter
	shortened notifier_info struct name
v1->v2: fix notifier_call parameter in call_netdevice_notifier()
Signed-off-by: David S. Miller <davem@davemloft.net>

7 files changed, 54 insertions, 18 deletions

diff --git a/net/core/dev.c b/net/core/dev.c
index 5f747974ac58..54fce6006a83 100644
--- a/net/core/dev.c
+++ b/net/core/dev.c
@@ -1391,6 +1391,20 @@ void dev_disable_lro(struct net_device *dev)
 }
 EXPORT_SYMBOL(dev_disable_lro);
 
+static void netdev_notifier_info_init(struct netdev_notifier_info *info,
+				      struct net_device *dev)
+{
+	info->dev = dev;
+}
+
+static int call_netdevice_notifier(struct notifier_block *nb, unsigned long val,
+				   struct net_device *dev)
+{
+	struct netdev_notifier_info info;
+
+	netdev_notifier_info_init(&info, dev);
+	return nb->notifier_call(nb, val, &info);
+}
 
 static int dev_boot_phase = 1;
 
@@ -1423,7 +1437,7 @@ int register_netdevice_notifier(struct notifier_block *nb)
 		goto unlock;
 	for_each_net(net) {
 		for_each_netdev(net, dev) {
-			err = nb->notifier_call(nb, NETDEV_REGISTER, dev);
+			err = call_netdevice_notifier(nb, NETDEV_REGISTER, dev);
 			err = notifier_to_errno(err);
 			if (err)
 				goto rollback;
@@ -1431,7 +1445,7 @@ int register_netdevice_notifier(struct notifier_block *nb)
 			if (!(dev->flags & IFF_UP))
 				continue;
 
-			nb->notifier_call(nb, NETDEV_UP, dev);
+			call_netdevice_notifier(nb, NETDEV_UP, dev);
 		}
 	}
 
@@ -1447,10 +1461,11 @@ rollback:
 				goto outroll;
 
 			if (dev->flags & IFF_UP) {
-				nb->notifier_call(nb, NETDEV_GOING_DOWN, dev);
-				nb->notifier_call(nb, NETDEV_DOWN, dev);
+				call_netdevice_notifier(nb, NETDEV_GOING_DOWN,
+							dev);
+				call_netdevice_notifier(nb, NETDEV_DOWN, dev);
 			}
-			nb->notifier_call(nb, NETDEV_UNREGISTER, dev);
+			call_netdevice_notifier(nb, NETDEV_UNREGISTER, dev);
 		}
 	}
 
@@ -1488,10 +1503,11 @@ int unregister_netdevice_notifier(struct notifier_block *nb)
 	for_each_net(net) {
 		for_each_netdev(net, dev) {
 			if (dev->flags & IFF_UP) {
-				nb->notifier_call(nb, NETDEV_GOING_DOWN, dev);
-				nb->notifier_call(nb, NETDEV_DOWN, dev);
+				call_netdevice_notifier(nb, NETDEV_GOING_DOWN,
+							dev);
+				call_netdevice_notifier(nb, NETDEV_DOWN, dev);
 			}
-			nb->notifier_call(nb, NETDEV_UNREGISTER, dev);
+			call_netdevice_notifier(nb, NETDEV_UNREGISTER, dev);
 		}
 	}
 unlock:
@@ -1501,6 +1517,25 @@ unlock:
 EXPORT_SYMBOL(unregister_netdevice_notifier);
 
 /**
+ *	call_netdevice_notifiers_info - call all network notifier blocks
+ *	@val: value passed unmodified to notifier function
+ *	@dev: net_device pointer passed unmodified to notifier function
+ *	@info: notifier information data
+ *
+ *	Call all network notifier blocks.  Parameters and return value
+ *	are as for raw_notifier_call_chain().
+ */
+
+int call_netdevice_notifiers_info(unsigned long val, struct net_device *dev,
+				  struct netdev_notifier_info *info)
+{
+	ASSERT_RTNL();
+	netdev_notifier_info_init(info, dev);
+	return raw_notifier_call_chain(&netdev_chain, val, info);
+}
+EXPORT_SYMBOL(call_netdevice_notifiers_info);
+
+/**
  *	call_netdevice_notifiers - call all network notifier blocks
  *      @val: value passed unmodified to notifier function
  *      @dev: net_device pointer passed unmodified to notifier function
@@ -1511,8 +1546,9 @@ EXPORT_SYMBOL(unregister_netdevice_notifier);
 
 int call_netdevice_notifiers(unsigned long val, struct net_device *dev)
 {
-	ASSERT_RTNL();
-	return raw_notifier_call_chain(&netdev_chain, val, dev);
+	struct netdev_notifier_info info;
+
+	return call_netdevice_notifiers_info(val, dev, &info);
 }
 EXPORT_SYMBOL(call_netdevice_notifiers);
 
diff --git a/net/core/drop_monitor.c b/net/core/drop_monitor.c
index d23b6682f4e9..5e78d44333b9 100644
--- a/net/core/drop_monitor.c
+++ b/net/core/drop_monitor.c
@@ -295,9 +295,9 @@ static int net_dm_cmd_trace(struct sk_buff *skb,
 }
 
 static int dropmon_net_event(struct notifier_block *ev_block,
-			unsigned long event, void *ptr)
+			     unsigned long event, void *ptr)
 {
-	struct net_device *dev = ptr;
+	struct net_device *dev = netdev_notifier_info_to_dev(ptr);
 	struct dm_hw_stat_delta *new_stat = NULL;
 	struct dm_hw_stat_delta *tmp;
 
diff --git a/net/core/dst.c b/net/core/dst.c
index df9cc810ec8e..ca4231ec7347 100644
--- a/net/core/dst.c
+++ b/net/core/dst.c
@@ -372,7 +372,7 @@ static void dst_ifdown(struct dst_entry *dst, struct net_device *dev,
 static int dst_dev_event(struct notifier_block *this, unsigned long event,
 			 void *ptr)
 {
-	struct net_device *dev = ptr;
+	struct net_device *dev = netdev_notifier_info_to_dev(ptr);
 	struct dst_entry *dst, *last = NULL;
 
 	switch (event) {
diff --git a/net/core/fib_rules.c b/net/core/fib_rules.c
index d5a9f8ead0d8..21735440c44a 100644
--- a/net/core/fib_rules.c
+++ b/net/core/fib_rules.c
@@ -705,9 +705,9 @@ static void detach_rules(struct list_head *rules, struct net_device *dev)
 
 
 static int fib_rules_event(struct notifier_block *this, unsigned long event,
-			    void *ptr)
+			   void *ptr)
 {
-	struct net_device *dev = ptr;
+	struct net_device *dev = netdev_notifier_info_to_dev(ptr);
 	struct net *net = dev_net(dev);
 	struct fib_rules_ops *ops;
 
diff --git a/net/core/netprio_cgroup.c b/net/core/netprio_cgroup.c
index 0777d0aa18c3..e533259dce3c 100644
--- a/net/core/netprio_cgroup.c
+++ b/net/core/netprio_cgroup.c
@@ -261,7 +261,7 @@ struct cgroup_subsys net_prio_subsys = {
 static int netprio_device_event(struct notifier_block *unused,
 				unsigned long event, void *ptr)
 {
-	struct net_device *dev = ptr;
+	struct net_device *dev = netdev_notifier_info_to_dev(ptr);
 	struct netprio_map *old;
 
 	/*
diff --git a/net/core/pktgen.c b/net/core/pktgen.c
index 11f2704c3810..795498fd4587 100644
--- a/net/core/pktgen.c
+++ b/net/core/pktgen.c
@@ -1921,7 +1921,7 @@ static void pktgen_change_name(const struct pktgen_net *pn, struct net_device *d
 static int pktgen_device_event(struct notifier_block *unused,
 			       unsigned long event, void *ptr)
 {
-	struct net_device *dev = ptr;
+	struct net_device *dev = netdev_notifier_info_to_dev(ptr);
 	struct pktgen_net *pn = net_generic(dev_net(dev), pg_net_id);
 
 	if (pn->pktgen_exiting)
diff --git a/net/core/rtnetlink.c b/net/core/rtnetlink.c
index a08bd2b7fe3f..49c14451d8ab 100644
--- a/net/core/rtnetlink.c
+++ b/net/core/rtnetlink.c
@@ -2667,7 +2667,7 @@ static void rtnetlink_rcv(struct sk_buff *skb)
 
 static int rtnetlink_event(struct notifier_block *this, unsigned long event, void *ptr)
 {
-	struct net_device *dev = ptr;
+	struct net_device *dev = netdev_notifier_info_to_dev(ptr);
 
 	switch (event) {
 	case NETDEV_UP: