linux-imx

// SPDX-License-Identifier: GPL-2.0

/* Copyright (c) 2018, Intel Corporation. */

​

/* A common module to handle registrations and notifications for paravirtual

 * drivers to enable accelerated datapath and support VF live migration.

 *

 * The notifier and event handling code is based on netvsc driver.

 */

​

#include <linux/module.h>

#include <linux/etherdevice.h>

#include <uapi/linux/if_arp.h>

#include <linux/rtnetlink.h>

#include <linux/if_vlan.h>

#include <net/failover.h>

​

static LIST_HEAD(failover_list);

static DEFINE_SPINLOCK(failover_lock);

​

static struct net_device *failover_get_bymac(u8 *mac, struct failover_ops **ops)

{

    struct net_device *failover_dev;

    struct failover *failover;

​

    spin_lock(&failover_lock);

    list_for_each_entry(failover, &failover_list, list) {

        failover_dev = rtnl_dereference(failover->failover_dev);

        if (ether_addr_equal(failover_dev->perm_addr, mac)) {

            *ops = rtnl_dereference(failover->ops);

            spin_unlock(&failover_lock);

            return failover_dev;

        }

    }

    spin_unlock(&failover_lock);

    return NULL;

}

​

/**

 * failover_slave_register - Register a slave netdev

 *

 * @slave_dev: slave netdev that is being registered

 *

 * Registers a slave device to a failover instance. Only ethernet devices

 * are supported.

 */

static int failover_slave_register(struct net_device *slave_dev)

{

    struct netdev_lag_upper_info lag_upper_info;

    struct net_device *failover_dev;

    struct failover_ops *fops;

    int err;

​

    if (slave_dev->type != ARPHRD_ETHER)

        goto done;

​

    ASSERT_RTNL();

​

    failover_dev = failover_get_bymac(slave_dev->perm_addr, &fops);

    if (!failover_dev)

        goto done;

​

    if (fops && fops->slave_pre_register &&

        fops->slave_pre_register(slave_dev, failover_dev))

        goto done;

​

    err = netdev_rx_handler_register(slave_dev, fops->slave_handle_frame,

                     failover_dev);

    if (err) {

        netdev_err(slave_dev, "can not register failover rx handler (err = %d)\n",

               err);

        goto done;

    }

​

    lag_upper_info.tx_type = NETDEV_LAG_TX_TYPE_ACTIVEBACKUP;

    err = netdev_master_upper_dev_link(slave_dev, failover_dev, NULL,

                       &lag_upper_info, NULL);

    if (err) {

        netdev_err(slave_dev, "can not set failover device %s (err = %d)\n",

               failover_dev->name, err);

        goto err_upper_link;

    }

​

    slave_dev->priv_flags |= IFF_FAILOVER_SLAVE;

​

    if (fops && fops->slave_register &&

        !fops->slave_register(slave_dev, failover_dev))

        return NOTIFY_OK;

​

    netdev_upper_dev_unlink(slave_dev, failover_dev);

    slave_dev->priv_flags &= ~IFF_FAILOVER_SLAVE;

err_upper_link:

    netdev_rx_handler_unregister(slave_dev);