/*
- * Copyright (c) 2009, 2010 Nicira Networks.
+ * Copyright (c) 2009, 2010, 2011 Nicira Networks.
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
*
* May return -EOPNOTSUPP if a network device does not implement packet
* reception through this interface. This function may be set to null if
- * it would always return -EOPNOTSUPP anyhow. (This will disable the OVS
- * integrated DHCP client and OpenFlow controller discovery, and prevent
- * the network device from being usefully used by the netdev-based
- * "userspace datapath".) */
+ * it would always return -EOPNOTSUPP anyhow. (This will prevent the
+ * network device from being usefully used by the netdev-based "userspace
+ * datapath".) */
int (*recv)(struct netdev *netdev, void *buffer, size_t size);
/* Registers with the poll loop to wake up from the next call to
*
* May return EOPNOTSUPP if a network device does not implement packet
* transmission through this interface. This function may be set to null
- * if it would always return EOPNOTSUPP anyhow. (This will disable the OVS
- * integrated DHCP client and OpenFlow controller discovery, and prevent
- * the network device from being usefully used by the netdev-based
- * "userspace datapath".) */
+ * if it would always return EOPNOTSUPP anyhow. (This will prevent the
+ * network device from being usefully used by the netdev-based "userspace
+ * datapath".) */
int (*send)(struct netdev *netdev, const void *buffer, size_t size);
/* Registers with the poll loop to wake up from the next call to
*
* The MTU is the maximum size of transmitted (and received) packets, in
* bytes, not including the hardware header; thus, this is typically 1500
- * bytes for Ethernet devices.*/
+ * bytes for Ethernet devices.
+ *
+ * If 'netdev' does not have an MTU (e.g. as some tunnels do not), then
+ * this function should set '*mtup' to INT_MAX. */
int (*get_mtu)(const struct netdev *netdev, int *mtup);
/* Returns the ifindex of 'netdev', if successful, as a positive number.