rtnetlink: Document.

[mirror_ovs.git] / lib / netdev-linux.h

/*
 * Copyright (c) 2009 Nicira Networks.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at:
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

#ifndef NETDEV_LINUX_H
#define NETDEV_LINUX_H 1

/* These functions are specific to the Linux implementation of dpif and netdev.
 * They should only be used directly by Linux-specific code. */

#include "list.h"

/* A digested version of an rtnetlink message sent down by the kernel to
 * indicate that a network device has been created or destroyed or changed.  */
struct rtnetlink_change {
    /* Copied from struct nlmsghdr. */
    int nlmsg_type;             /* e.g. RTM_NEWLINK, RTM_DELLINK. */

    /* Copied from struct ifinfomsg. */
    int ifi_index;              /* Index of network device. */

    /* Extracted from Netlink attributes. */
    const char *ifname;         /* Name of network device. */
    int master_ifindex;         /* Ifindex of datapath master (0 if none). */
};

/* Function called to report that a netdev has changed.  'change' describes the
 * specific change.  It may be null if the buffer of change information
 * overflowed, in which case the function must assume that every device may
 * have changed.  'aux' is as specified in the call to
 * lxnetdev_notifier_register().  */
typedef void rtnetlink_notify_func(const struct rtnetlink_change *, void *aux);

struct rtnetlink_notifier {
    struct list node;
    rtnetlink_notify_func *cb;
    void *aux;
};

int rtnetlink_notifier_register(struct rtnetlink_notifier *,
                                rtnetlink_notify_func *, void *aux);
void rtnetlink_notifier_unregister(struct rtnetlink_notifier *);
void rtnetlink_notifier_run(void);
void rtnetlink_notifier_wait(void);

#endif /* netdev-linux.h */