net: add change_carrier netdev op
This allows a driver to register change_carrier callback which will be
called whenever user will like to change carrier state. This is useful
for devices like dummy, gre, team and so on.
Signed-off-by: Jiri Pirko <jiri@resnulli.us>
Acked-by: Flavio Leitner <fbl@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/include/linux/netdevice.h b/include/linux/netdevice.h
index c599e47..0e1b92a 100644
--- a/include/linux/netdevice.h
+++ b/include/linux/netdevice.h
@@ -891,6 +891,14 @@
* int (*ndo_bridge_setlink)(struct net_device *dev, struct nlmsghdr *nlh)
* int (*ndo_bridge_getlink)(struct sk_buff *skb, u32 pid, u32 seq,
* struct net_device *dev)
+ *
+ * int (*ndo_change_carrier)(struct net_device *dev, bool new_carrier);
+ * Called to change device carrier. Soft-devices (like dummy, team, etc)
+ * which do not represent real hardware may define this to allow their
+ * userspace components to manage their virtual carrier state. Devices
+ * that determine carrier state from physical hardware properties (eg
+ * network cables) or protocol-dependent mechanisms (eg
+ * USB_CDC_NOTIFY_NETWORK_CONNECTION) should NOT implement this function.
*/
struct net_device_ops {
int (*ndo_init)(struct net_device *dev);
@@ -1008,6 +1016,8 @@
int (*ndo_bridge_getlink)(struct sk_buff *skb,
u32 pid, u32 seq,
struct net_device *dev);
+ int (*ndo_change_carrier)(struct net_device *dev,
+ bool new_carrier);
};
/*
@@ -2194,6 +2204,8 @@
extern void dev_set_group(struct net_device *, int);
extern int dev_set_mac_address(struct net_device *,
struct sockaddr *);
+extern int dev_change_carrier(struct net_device *,
+ bool new_carrier);
extern int dev_hard_start_xmit(struct sk_buff *skb,
struct net_device *dev,
struct netdev_queue *txq);
diff --git a/net/core/dev.c b/net/core/dev.c
index 515473e..21c5b97 100644
--- a/net/core/dev.c
+++ b/net/core/dev.c
@@ -5027,6 +5027,25 @@
}
EXPORT_SYMBOL(dev_set_mac_address);
+/**
+ * dev_change_carrier - Change device carrier
+ * @dev: device
+ * @new_carries: new value
+ *
+ * Change device carrier
+ */
+int dev_change_carrier(struct net_device *dev, bool new_carrier)
+{
+ const struct net_device_ops *ops = dev->netdev_ops;
+
+ if (!ops->ndo_change_carrier)
+ return -EOPNOTSUPP;
+ if (!netif_device_present(dev))
+ return -ENODEV;
+ return ops->ndo_change_carrier(dev, new_carrier);
+}
+EXPORT_SYMBOL(dev_change_carrier);
+
/*
* Perform the SIOCxIFxxx calls, inside rcu_read_lock()
*/