net: s/__dev_set_mtu/__netif_set_mtu/

Commit cc34acd577f1 ("docs: net: document new locking reality")
introduced netif_ vs dev_ function semantics: the former expects locked
netdev, the latter takes care of the locking. We don't strictly
follow this semantics on either side, but there are more dev_xxx handlers
now that don't fit. Rename them to netif_xxx where appropriate.

__netif_set_mtu is used only by bond, so move it into
NETDEV_INTERNAL namespace.

Signed-off-by: Stanislav Fomichev <[e-mail]>
Link: https://patch.msgid.link/[e-mail]
Signed-off-by: Jakub Kicinski <[e-mail]>

drivers/net/bonding/bond_main.c

···
 
 	if (unregister) {
 		netdev_lock_ops(slave_dev);
-		__dev_set_mtu(slave_dev, slave->original_mtu);
+		__netif_set_mtu(slave_dev, slave->original_mtu);
 		netdev_unlock_ops(slave_dev);
 	} else {
 		dev_set_mtu(slave_dev, slave->original_mtu);

include/linux/netdevice.h

···
 			       struct netlink_ext_ack *extack);
 int dev_change_net_namespace(struct net_device *dev, struct net *net,
 			     const char *pat);
-int __dev_set_mtu(struct net_device *, int);
+int __netif_set_mtu(struct net_device *dev, int new_mtu);
 int netif_set_mtu(struct net_device *dev, int new_mtu);
 int dev_set_mtu(struct net_device *, int);
 int netif_pre_changeaddr_notify(struct net_device *dev, const char *addr,

net/core/dev.c

···
 	return ret;
 }
 
-int __dev_set_mtu(struct net_device *dev, int new_mtu)
+int __netif_set_mtu(struct net_device *dev, int new_mtu)
 {
 	const struct net_device_ops *ops = dev->netdev_ops;
 
···
 	WRITE_ONCE(dev->mtu, new_mtu);
 	return 0;
 }
-EXPORT_SYMBOL(__dev_set_mtu);
+EXPORT_SYMBOL_NS_GPL(__netif_set_mtu, "NETDEV_INTERNAL");
 
 int dev_validate_mtu(struct net_device *dev, int new_mtu,
 		     struct netlink_ext_ack *extack)
···
 }
 
 /**
- *	netif_set_mtu_ext - Change maximum transfer unit
- *	@dev: device
- *	@new_mtu: new transfer unit
- *	@extack: netlink extended ack
+ * netif_set_mtu_ext() - Change maximum transfer unit
+ * @dev: device
+ * @new_mtu: new transfer unit
+ * @extack: netlink extended ack
  *
- *	Change the maximum transfer size of the network device.
+ * Change the maximum transfer size of the network device.
+ *
+ * Return: 0 on success, -errno on failure.
  */
 int netif_set_mtu_ext(struct net_device *dev, int new_mtu,
 		      struct netlink_ext_ack *extack)
 {
 	int err, orig_mtu;
+
+	netdev_ops_assert_locked(dev);
 
 	if (new_mtu == dev->mtu)
 		return 0;
···
 		return err;
 
 	orig_mtu = dev->mtu;
-	err = __dev_set_mtu(dev, new_mtu);
+	err = __netif_set_mtu(dev, new_mtu);
 
 	if (!err) {
 		err = call_netdevice_notifiers_mtu(NETDEV_CHANGEMTU, dev,
···
 			/* setting mtu back and notifying everyone again,
 			 * so that they have a chance to revert changes.
 			 */
-			__dev_set_mtu(dev, orig_mtu);
+			__netif_set_mtu(dev, orig_mtu);
 			call_netdevice_notifiers_mtu(NETDEV_CHANGEMTU, dev,
 						     new_mtu);
 		}