// SPDX-License-Identifier: GPL-2.0-or-later
/* Copyright Amazon.com Inc. or its affiliates. */

#include <linux/init.h>
#include <linux/netdevice.h>
#include <linux/notifier.h>
#include <linux/rtnetlink.h>
#include <net/net_namespace.h>
#include <net/netdev_lock.h>
#include <net/netns/generic.h>

int netdev_debug_event(struct notifier_block *nb, unsigned long event,
                       void *ptr)
{
        struct net_device *dev = netdev_notifier_info_to_dev(ptr);
        struct net *net = dev_net(dev);
        enum netdev_cmd cmd = event;

        /* Keep enum and don't add default to trigger -Werror=switch */
        switch (cmd) {
        case NETDEV_XDP_FEAT_CHANGE:
                netdev_assert_locked(dev);
                fallthrough;
        case NETDEV_CHANGE:
        case NETDEV_REGISTER:
        case NETDEV_UP:
                netdev_ops_assert_locked(dev);
                fallthrough;
        case NETDEV_DOWN:
        case NETDEV_REBOOT:
        case NETDEV_UNREGISTER:
        case NETDEV_CHANGEMTU:
        case NETDEV_CHANGEADDR:
        case NETDEV_PRE_CHANGEADDR:
        case NETDEV_GOING_DOWN:
        case NETDEV_FEAT_CHANGE:
        case NETDEV_BONDING_FAILOVER:
        case NETDEV_PRE_UP:
        case NETDEV_PRE_TYPE_CHANGE:
        case NETDEV_POST_TYPE_CHANGE:
        case NETDEV_POST_INIT:
        case NETDEV_PRE_UNINIT:
        case NETDEV_RELEASE:
        case NETDEV_NOTIFY_PEERS:
        case NETDEV_JOIN:
        case NETDEV_CHANGEUPPER:
        case NETDEV_RESEND_IGMP:
        case NETDEV_PRECHANGEMTU:
        case NETDEV_CHANGEINFODATA:
        case NETDEV_BONDING_INFO:
        case NETDEV_PRECHANGEUPPER:
        case NETDEV_CHANGELOWERSTATE:
        case NETDEV_UDP_TUNNEL_PUSH_INFO:
        case NETDEV_UDP_TUNNEL_DROP_INFO:
        case NETDEV_CHANGE_TX_QUEUE_LEN:
        case NETDEV_CVLAN_FILTER_PUSH_INFO:
        case NETDEV_CVLAN_FILTER_DROP_INFO:
        case NETDEV_SVLAN_FILTER_PUSH_INFO:
        case NETDEV_SVLAN_FILTER_DROP_INFO:
        case NETDEV_OFFLOAD_XSTATS_ENABLE:
        case NETDEV_OFFLOAD_XSTATS_DISABLE:
        case NETDEV_OFFLOAD_XSTATS_REPORT_USED:
        case NETDEV_OFFLOAD_XSTATS_REPORT_DELTA:
                ASSERT_RTNL();
                break;

        case NETDEV_CHANGENAME:
                ASSERT_RTNL_NET(net);
                break;
        }

        return NOTIFY_DONE;
}
EXPORT_SYMBOL_NS_GPL(netdev_debug_event, "NETDEV_INTERNAL");

static int rtnl_net_debug_net_id;

static int __net_init rtnl_net_debug_net_init(struct net *net)
{
        struct notifier_block *nb;

        nb = net_generic(net, rtnl_net_debug_net_id);
        nb->notifier_call = netdev_debug_event;

        return register_netdevice_notifier_net(net, nb);
}

static void __net_exit rtnl_net_debug_net_exit(struct net *net)
{
        struct notifier_block *nb;

        nb = net_generic(net, rtnl_net_debug_net_id);
        unregister_netdevice_notifier_net(net, nb);
}

static struct pernet_operations rtnl_net_debug_net_ops __net_initdata = {
        .init = rtnl_net_debug_net_init,
        .exit = rtnl_net_debug_net_exit,
        .id = &rtnl_net_debug_net_id,
        .size = sizeof(struct notifier_block),
};

static struct notifier_block rtnl_net_debug_block = {
        .notifier_call = netdev_debug_event,
};

static int __init rtnl_net_debug_init(void)
{
        int ret;

        ret = register_pernet_subsys(&rtnl_net_debug_net_ops);
        if (ret)
                return ret;

        ret = register_netdevice_notifier(&rtnl_net_debug_block);
        if (ret)
                unregister_pernet_subsys(&rtnl_net_debug_net_ops);

        return ret;
}

subsys_initcall(rtnl_net_debug_init);