1 files changed, 31 insertions, 22 deletions

diff --git a/net/decnet/dn_dev.c b/net/decnet/dn_dev.c
index 1b1daeb151f2..238af093495b 100644
--- a/net/decnet/dn_dev.c
+++ b/net/decnet/dn_dev.c
@@ -68,7 +68,7 @@ extern struct neigh_table dn_neigh_table;
  */
 __le16 decnet_address = 0;
 
-static DEFINE_RWLOCK(dndev_lock);
+static DEFINE_SPINLOCK(dndev_lock);
 static struct net_device *decnet_default_device;
 static BLOCKING_NOTIFIER_HEAD(dnaddr_chain);
 
@@ -499,7 +499,8 @@ rarok:
 struct net_device *dn_dev_get_default(void)
 {
 	struct net_device *dev;
-	read_lock(&dndev_lock);
+
+	spin_lock(&dndev_lock);
 	dev = decnet_default_device;
 	if (dev) {
 		if (dev->dn_ptr)
@@ -507,7 +508,8 @@ struct net_device *dn_dev_get_default(void)
 		else
 			dev = NULL;
 	}
-	read_unlock(&dndev_lock);
+	spin_unlock(&dndev_lock);
+
 	return dev;
 }
 
@@ -517,13 +519,15 @@ int dn_dev_set_default(struct net_device *dev, int force)
 	int rv = -EBUSY;
 	if (!dev->dn_ptr)
 		return -ENODEV;
-	write_lock(&dndev_lock);
+
+	spin_lock(&dndev_lock);
 	if (force || decnet_default_device == NULL) {
 		old = decnet_default_device;
 		decnet_default_device = dev;
 		rv = 0;
 	}
-	write_unlock(&dndev_lock);
+	spin_unlock(&dndev_lock);
+
 	if (old)
 		dev_put(old);
 	return rv;
@@ -531,26 +535,29 @@ int dn_dev_set_default(struct net_device *dev, int force)
 
 static void dn_dev_check_default(struct net_device *dev)
 {
-	write_lock(&dndev_lock);
+	spin_lock(&dndev_lock);
 	if (dev == decnet_default_device) {
 		decnet_default_device = NULL;
 	} else {
 		dev = NULL;
 	}
-	write_unlock(&dndev_lock);
+	spin_unlock(&dndev_lock);
+
 	if (dev)
 		dev_put(dev);
 }
 
+/*
+ * Called with RTNL
+ */
 static struct dn_dev *dn_dev_by_index(int ifindex)
 {
 	struct net_device *dev;
 	struct dn_dev *dn_dev = NULL;
-	dev = dev_get_by_index(&init_net, ifindex);
-	if (dev) {
+
+	dev = __dev_get_by_index(&init_net, ifindex);
+	if (dev)
 		dn_dev = dev->dn_ptr;
-		dev_put(dev);
-	}
 
 	return dn_dev;
 }
@@ -571,7 +578,7 @@ static int dn_nl_deladdr(struct sk_buff *skb, struct nlmsghdr *nlh, void *arg)
 	struct dn_ifaddr *ifa, **ifap;
 	int err = -EINVAL;
 
-	if (net != &init_net)
+	if (!net_eq(net, &init_net))
 		goto errout;
 
 	err = nlmsg_parse(nlh, sizeof(*ifm), tb, IFA_MAX, dn_ifa_policy);
@@ -610,7 +617,7 @@ static int dn_nl_newaddr(struct sk_buff *skb, struct nlmsghdr *nlh, void *arg)
 	struct dn_ifaddr *ifa;
 	int err;
 
-	if (net != &init_net)
+	if (!net_eq(net, &init_net))
 		return -EINVAL;
 
 	err = nlmsg_parse(nlh, sizeof(*ifm), tb, IFA_MAX, dn_ifa_policy);
@@ -724,7 +731,7 @@ static int dn_nl_dump_ifaddr(struct sk_buff *skb, struct netlink_callback *cb)
 	struct dn_dev *dn_db;
 	struct dn_ifaddr *ifa;
 
-	if (net != &init_net)
+	if (!net_eq(net, &init_net))
 		return 0;
 
 	skip_ndevs = cb->args[0];
@@ -768,13 +775,17 @@ static int dn_dev_get_first(struct net_device *dev, __le16 *addr)
 	struct dn_dev *dn_db = (struct dn_dev *)dev->dn_ptr;
 	struct dn_ifaddr *ifa;
 	int rv = -ENODEV;
+
 	if (dn_db == NULL)
 		goto out;
+
+	rtnl_lock();
 	ifa = dn_db->ifa_list;
 	if (ifa != NULL) {
 		*addr = ifa->ifa_local;
 		rv = 0;
 	}
+	rtnl_unlock();
 out:
 	return rv;
 }
@@ -796,9 +807,7 @@ int dn_dev_bind_default(__le16 *addr)
 	dev = dn_dev_get_default();
 last_chance:
 	if (dev) {
-		read_lock(&dev_base_lock);
 		rv = dn_dev_get_first(dev, addr);
-		read_unlock(&dev_base_lock);
 		dev_put(dev);
 		if (rv == 0 || dev == init_net.loopback_dev)
 			return rv;
@@ -1263,18 +1272,18 @@ static inline int is_dn_dev(struct net_device *dev)
 }
 
 static void *dn_dev_seq_start(struct seq_file *seq, loff_t *pos)
-	__acquires(&dev_base_lock)
+	__acquires(rcu)
 {
 	int i;
 	struct net_device *dev;
 
-	read_lock(&dev_base_lock);
+	rcu_read_lock();
 
 	if (*pos == 0)
 		return SEQ_START_TOKEN;
 
 	i = 1;
-	for_each_netdev(&init_net, dev) {
+	for_each_netdev_rcu(&init_net, dev) {
 		if (!is_dn_dev(dev))
 			continue;
 
@@ -1295,7 +1304,7 @@ static void *dn_dev_seq_next(struct seq_file *seq, void *v, loff_t *pos)
 	if (v == SEQ_START_TOKEN)
 		dev = net_device_entry(&init_net.dev_base_head);
 
-	for_each_netdev_continue(&init_net, dev) {
+	for_each_netdev_continue_rcu(&init_net, dev) {
 		if (!is_dn_dev(dev))
 			continue;
 
@@ -1306,9 +1315,9 @@ static void *dn_dev_seq_next(struct seq_file *seq, void *v, loff_t *pos)
 }
 
 static void dn_dev_seq_stop(struct seq_file *seq, void *v)
-	__releases(&dev_base_lock)
+	__releases(rcu)
 {
-	read_unlock(&dev_base_lock);
+	rcu_read_unlock();
 }
 
 static char *dn_type2asc(char type)