/*
 * Copyright (c) 2015, Mellanox Technologies inc.  All rights reserved.
 *
 * This software is available to you under a choice of one of two
 * licenses.  You may choose to be licensed under the terms of the GNU
 * General Public License (GPL) Version 2, available from the file
 * COPYING in the main directory of this source tree, or the
 * OpenIB.org BSD license below:
 *
 *     Redistribution and use in source and binary forms, with or
 *     without modification, are permitted provided that the following
 *     conditions are met:
 *
 *      - Redistributions of source code must retain the above
 *        copyright notice, this list of conditions and the following
 *        disclaimer.
 *
 *      - Redistributions in binary form must reproduce the above
 *        copyright notice, this list of conditions and the following
 *        disclaimer in the documentation and/or other materials
 *        provided with the distribution.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
 * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
 * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
 * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
 * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
 * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
 * SOFTWARE.
 */

#include "core_priv.h"

#include <linux/in.h>
#include <linux/in6.h>

/* For in6_dev_get/in6_dev_put */
#include <net/addrconf.h>
#include <net/bonding.h>

#include <rdma/ib_cache.h>
#include <rdma/ib_addr.h>

static struct workqueue_struct *gid_cache_wq;

static struct workqueue_struct *gid_cache_wq;

enum gid_op_type {
        GID_DEL = 0,
        GID_ADD
};

struct update_gid_event_work {
        struct work_struct work;
        union ib_gid       gid;
        struct ib_gid_attr gid_attr;
        enum gid_op_type gid_op;
};

#define ROCE_NETDEV_CALLBACK_SZ         3
struct netdev_event_work_cmd {
        roce_netdev_callback    cb;
        roce_netdev_filter      filter;
        struct net_device       *ndev;
        struct net_device       *filter_ndev;
};

struct netdev_event_work {
        struct work_struct              work;
        struct netdev_event_work_cmd    cmds[ROCE_NETDEV_CALLBACK_SZ];
};

static const struct {
        bool (*is_supported)(const struct ib_device *device, u8 port_num);
        enum ib_gid_type gid_type;
} PORT_CAP_TO_GID_TYPE[] = {
        {rdma_protocol_roce_eth_encap, IB_GID_TYPE_ROCE},
        {rdma_protocol_roce_udp_encap, IB_GID_TYPE_ROCE_UDP_ENCAP},
};

#define CAP_TO_GID_TABLE_SIZE   ARRAY_SIZE(PORT_CAP_TO_GID_TYPE)

unsigned long roce_gid_type_mask_support(struct ib_device *ib_dev, u8 port)
{
        int i;
        unsigned int ret_flags = 0;

        if (!rdma_protocol_roce(ib_dev, port))
                return 1UL << IB_GID_TYPE_IB;

        for (i = 0; i < CAP_TO_GID_TABLE_SIZE; i++)
                if (PORT_CAP_TO_GID_TYPE[i].is_supported(ib_dev, port))
                        ret_flags |= 1UL << PORT_CAP_TO_GID_TYPE[i].gid_type;

        return ret_flags;
}
EXPORT_SYMBOL(roce_gid_type_mask_support);

static void update_gid(enum gid_op_type gid_op, struct ib_device *ib_dev,
                       u8 port, union ib_gid *gid,
                       struct ib_gid_attr *gid_attr)
{
        int i;
        unsigned long gid_type_mask = roce_gid_type_mask_support(ib_dev, port);

        for (i = 0; i < IB_GID_TYPE_SIZE; i++) {
                if ((1UL << i) & gid_type_mask) {
                        gid_attr->gid_type = i;
                        switch (gid_op) {
                        case GID_ADD:
                                ib_cache_gid_add(ib_dev, port,
                                                 gid, gid_attr);
                                break;
                        case GID_DEL:
                                ib_cache_gid_del(ib_dev, port,
                                                 gid, gid_attr);
                                break;
                        }
                }
        }
}

enum bonding_slave_state {
        BONDING_SLAVE_STATE_ACTIVE      = 1UL << 0,
        BONDING_SLAVE_STATE_INACTIVE    = 1UL << 1,
        /* No primary slave or the device isn't a slave in bonding */
        BONDING_SLAVE_STATE_NA          = 1UL << 2,
};

static enum bonding_slave_state is_eth_active_slave_of_bonding_rcu(struct net_device *dev,
                                                                   struct net_device *upper)
{
        if (upper && netif_is_bond_master(upper)) {
                struct net_device *pdev =
                        bond_option_active_slave_get_rcu(netdev_priv(upper));

                if (pdev)
                        return dev == pdev ? BONDING_SLAVE_STATE_ACTIVE :
                                BONDING_SLAVE_STATE_INACTIVE;
        }

        return BONDING_SLAVE_STATE_NA;
}

#define REQUIRED_BOND_STATES            (BONDING_SLAVE_STATE_ACTIVE |   \
                                         BONDING_SLAVE_STATE_NA)
static int is_eth_port_of_netdev(struct ib_device *ib_dev, u8 port,
                                 struct net_device *rdma_ndev, void *cookie)
{
        struct net_device *real_dev;
        int res;

        if (!rdma_ndev)
                return 0;

        rcu_read_lock();
        real_dev = rdma_vlan_dev_real_dev(cookie);
        if (!real_dev)
                real_dev = cookie;

        res = ((rdma_is_upper_dev_rcu(rdma_ndev, cookie) &&
               (is_eth_active_slave_of_bonding_rcu(rdma_ndev, real_dev) &
                REQUIRED_BOND_STATES)) ||
               real_dev == rdma_ndev);

        rcu_read_unlock();
        return res;
}

static int is_eth_port_inactive_slave(struct ib_device *ib_dev, u8 port,
                                      struct net_device *rdma_ndev, void *cookie)
{
        struct net_device *master_dev;
        int res;

        if (!rdma_ndev)
                return 0;

        rcu_read_lock();
        master_dev = netdev_master_upper_dev_get_rcu(rdma_ndev);
        res = is_eth_active_slave_of_bonding_rcu(rdma_ndev, master_dev) ==
                BONDING_SLAVE_STATE_INACTIVE;
        rcu_read_unlock();

        return res;
}

static int pass_all_filter(struct ib_device *ib_dev, u8 port,
                           struct net_device *rdma_ndev, void *cookie)
{
        return 1;
}

static int upper_device_filter(struct ib_device *ib_dev, u8 port,
                               struct net_device *rdma_ndev, void *cookie)
{
        int res;

        if (!rdma_ndev)
                return 0;

        if (rdma_ndev == cookie)
                return 1;

        rcu_read_lock();
        res = rdma_is_upper_dev_rcu(rdma_ndev, cookie);
        rcu_read_unlock();

        return res;
}

static void update_gid_ip(enum gid_op_type gid_op,
                          struct ib_device *ib_dev,
                          u8 port, struct net_device *ndev,
                          struct sockaddr *addr)
{
        union ib_gid gid;
        struct ib_gid_attr gid_attr;

        rdma_ip2gid(addr, &gid);
        memset(&gid_attr, 0, sizeof(gid_attr));
        gid_attr.ndev = ndev;

        update_gid(gid_op, ib_dev, port, &gid, &gid_attr);
}

static void enum_netdev_default_gids(struct ib_device *ib_dev,
                                     u8 port, struct net_device *event_ndev,
                                     struct net_device *rdma_ndev)
{
        unsigned long gid_type_mask;

        rcu_read_lock();
        if (!rdma_ndev ||
            ((rdma_ndev != event_ndev &&
              !rdma_is_upper_dev_rcu(rdma_ndev, event_ndev)) ||
             is_eth_active_slave_of_bonding_rcu(rdma_ndev,
                                                netdev_master_upper_dev_get_rcu(rdma_ndev)) ==
             BONDING_SLAVE_STATE_INACTIVE)) {
                rcu_read_unlock();
                return;
        }
        rcu_read_unlock();

        gid_type_mask = roce_gid_type_mask_support(ib_dev, port);

        ib_cache_gid_set_default_gid(ib_dev, port, rdma_ndev, gid_type_mask,
                                     IB_CACHE_GID_DEFAULT_MODE_SET);
}

static void bond_delete_netdev_default_gids(struct ib_device *ib_dev,
                                            u8 port,
                                            struct net_device *event_ndev,
                                            struct net_device *rdma_ndev)
{
        struct net_device *real_dev = rdma_vlan_dev_real_dev(event_ndev);
        unsigned long gid_type_mask;

        if (!rdma_ndev)
                return;

        if (!real_dev)
                real_dev = event_ndev;

        rcu_read_lock();

        if (((rdma_ndev != event_ndev &&
              !rdma_is_upper_dev_rcu(rdma_ndev, event_ndev)) ||
             is_eth_active_slave_of_bonding_rcu(rdma_ndev, real_dev)
                                                 ==
             BONDING_SLAVE_STATE_INACTIVE)) {
                rcu_read_unlock();
                return;
        }

        rcu_read_unlock();

        gid_type_mask = roce_gid_type_mask_support(ib_dev, port);

        ib_cache_gid_set_default_gid(ib_dev, port, rdma_ndev,
                                     gid_type_mask,
                                     IB_CACHE_GID_DEFAULT_MODE_DELETE);
}

static void enum_netdev_ipv4_ips(struct ib_device *ib_dev,
                                 u8 port, struct net_device *ndev)
{
        struct in_device *in_dev;
        struct sin_list {
                struct list_head        list;
                struct sockaddr_in      ip;
        };
        struct sin_list *sin_iter;
        struct sin_list *sin_temp;

        LIST_HEAD(sin_list);
        if (ndev->reg_state >= NETREG_UNREGISTERING)
                return;

        rcu_read_lock();
        in_dev = __in_dev_get_rcu(ndev);
        if (!in_dev) {
                rcu_read_unlock();
                return;
        }

        for_ifa(in_dev) {
                struct sin_list *entry = kzalloc(sizeof(*entry), GFP_ATOMIC);

                if (!entry)
                        continue;

                entry->ip.sin_family = AF_INET;
                entry->ip.sin_addr.s_addr = ifa->ifa_address;
                list_add_tail(&entry->list, &sin_list);
        }
        endfor_ifa(in_dev);
        rcu_read_unlock();

        list_for_each_entry_safe(sin_iter, sin_temp, &sin_list, list) {
                update_gid_ip(GID_ADD, ib_dev, port, ndev,
                              (struct sockaddr *)&sin_iter->ip);
                list_del(&sin_iter->list);
                kfree(sin_iter);
        }
}

static void enum_netdev_ipv6_ips(struct ib_device *ib_dev,
                                 u8 port, struct net_device *ndev)
{
        struct inet6_ifaddr *ifp;
        struct inet6_dev *in6_dev;
        struct sin6_list {
                struct list_head        list;
                struct sockaddr_in6     sin6;
        };
        struct sin6_list *sin6_iter;
        struct sin6_list *sin6_temp;
        struct ib_gid_attr gid_attr = {.ndev = ndev};
        LIST_HEAD(sin6_list);

        if (ndev->reg_state >= NETREG_UNREGISTERING)
                return;

        in6_dev = in6_dev_get(ndev);
        if (!in6_dev)
                return;

        read_lock_bh(&in6_dev->lock);
        list_for_each_entry(ifp, &in6_dev->addr_list, if_list) {
                struct sin6_list *entry = kzalloc(sizeof(*entry), GFP_ATOMIC);

                if (!entry)
                        continue;

                entry->sin6.sin6_family = AF_INET6;
                entry->sin6.sin6_addr = ifp->addr;
                list_add_tail(&entry->list, &sin6_list);
        }
        read_unlock_bh(&in6_dev->lock);

        in6_dev_put(in6_dev);

        list_for_each_entry_safe(sin6_iter, sin6_temp, &sin6_list, list) {
                union ib_gid    gid;

                rdma_ip2gid((struct sockaddr *)&sin6_iter->sin6, &gid);
                update_gid(GID_ADD, ib_dev, port, &gid, &gid_attr);
                list_del(&sin6_iter->list);
                kfree(sin6_iter);
        }
}

static void _add_netdev_ips(struct ib_device *ib_dev, u8 port,
                            struct net_device *ndev)
{
        enum_netdev_ipv4_ips(ib_dev, port, ndev);
        if (IS_ENABLED(CONFIG_IPV6))
                enum_netdev_ipv6_ips(ib_dev, port, ndev);
}

static void add_netdev_ips(struct ib_device *ib_dev, u8 port,
                           struct net_device *rdma_ndev, void *cookie)
{
        enum_netdev_default_gids(ib_dev, port, cookie, rdma_ndev);
        _add_netdev_ips(ib_dev, port, cookie);
}

static void del_netdev_ips(struct ib_device *ib_dev, u8 port,
                           struct net_device *rdma_ndev, void *cookie)
{
        ib_cache_gid_del_all_netdev_gids(ib_dev, port, cookie);
}

static void enum_all_gids_of_dev_cb(struct ib_device *ib_dev,
                                    u8 port,
                                    struct net_device *rdma_ndev,
                                    void *cookie)
{
        struct net *net;
        struct net_device *ndev;

        /* Lock the rtnl to make sure the netdevs does not move under
         * our feet
         */
        rtnl_lock();
        down_read(&net_rwsem);
        for_each_net(net)
                for_each_netdev(net, ndev)
                        if (is_eth_port_of_netdev(ib_dev, port, rdma_ndev, ndev))
                                add_netdev_ips(ib_dev, port, rdma_ndev, ndev);
        up_read(&net_rwsem);
        rtnl_unlock();
}

/**
 * rdma_roce_rescan_device - Rescan all of the network devices in the system
 * and add their gids, as needed, to the relevant RoCE devices.
 *
 * @device:         the rdma device
 */
void rdma_roce_rescan_device(struct ib_device *ib_dev)
{
        ib_enum_roce_netdev(ib_dev, pass_all_filter, NULL,
                            enum_all_gids_of_dev_cb, NULL);
}
EXPORT_SYMBOL(rdma_roce_rescan_device);

static void callback_for_addr_gid_device_scan(struct ib_device *device,
                                              u8 port,
                                              struct net_device *rdma_ndev,
                                              void *cookie)
{
        struct update_gid_event_work *parsed = cookie;

        return update_gid(parsed->gid_op, device,
                          port, &parsed->gid,
                          &parsed->gid_attr);
}

struct upper_list {
        struct list_head list;
        struct net_device *upper;
};

static int netdev_upper_walk(struct net_device *upper, void *data)
{
        struct upper_list *entry = kmalloc(sizeof(*entry), GFP_ATOMIC);
        struct list_head *upper_list = data;

        if (!entry)
                return 0;

        list_add_tail(&entry->list, upper_list);
        dev_hold(upper);
        entry->upper = upper;

        return 0;
}

static void handle_netdev_upper(struct ib_device *ib_dev, u8 port,
                                void *cookie,
                                void (*handle_netdev)(struct ib_device *ib_dev,
                                                      u8 port,
                                                      struct net_device *ndev))
{
        struct net_device *ndev = cookie;
        struct upper_list *upper_iter;
        struct upper_list *upper_temp;
        LIST_HEAD(upper_list);

        rcu_read_lock();
        netdev_walk_all_upper_dev_rcu(ndev, netdev_upper_walk, &upper_list);
        rcu_read_unlock();

        handle_netdev(ib_dev, port, ndev);
        list_for_each_entry_safe(upper_iter, upper_temp, &upper_list,
                                 list) {
                handle_netdev(ib_dev, port, upper_iter->upper);
                dev_put(upper_iter->upper);
                list_del(&upper_iter->list);
                kfree(upper_iter);
        }
}

static void _roce_del_all_netdev_gids(struct ib_device *ib_dev, u8 port,
                                      struct net_device *event_ndev)
{
        ib_cache_gid_del_all_netdev_gids(ib_dev, port, event_ndev);
}

static void del_netdev_upper_ips(struct ib_device *ib_dev, u8 port,
                                 struct net_device *rdma_ndev, void *cookie)
{
        handle_netdev_upper(ib_dev, port, cookie, _roce_del_all_netdev_gids);
}

static void add_netdev_upper_ips(struct ib_device *ib_dev, u8 port,
                                 struct net_device *rdma_ndev, void *cookie)
{
        handle_netdev_upper(ib_dev, port, cookie, _add_netdev_ips);
}

static void del_netdev_default_ips_join(struct ib_device *ib_dev, u8 port,
                                        struct net_device *rdma_ndev,
                                        void *cookie)
{
        struct net_device *master_ndev;

        rcu_read_lock();
        master_ndev = netdev_master_upper_dev_get_rcu(rdma_ndev);
        if (master_ndev)
                dev_hold(master_ndev);
        rcu_read_unlock();

        if (master_ndev) {
                bond_delete_netdev_default_gids(ib_dev, port, master_ndev,
                                                rdma_ndev);
                dev_put(master_ndev);
        }
}

static void del_netdev_default_ips(struct ib_device *ib_dev, u8 port,
                                   struct net_device *rdma_ndev, void *cookie)
{
        bond_delete_netdev_default_gids(ib_dev, port, cookie, rdma_ndev);
}

/* The following functions operate on all IB devices. netdevice_event and
 * addr_event execute ib_enum_all_roce_netdevs through a work.
 * ib_enum_all_roce_netdevs iterates through all IB devices.
 */

static void netdevice_event_work_handler(struct work_struct *_work)
{
        struct netdev_event_work *work =
                container_of(_work, struct netdev_event_work, work);
        unsigned int i;

        for (i = 0; i < ARRAY_SIZE(work->cmds) && work->cmds[i].cb; i++) {
                ib_enum_all_roce_netdevs(work->cmds[i].filter,
                                         work->cmds[i].filter_ndev,
                                         work->cmds[i].cb,
                                         work->cmds[i].ndev);
                dev_put(work->cmds[i].ndev);
                dev_put(work->cmds[i].filter_ndev);
        }

        kfree(work);
}

static int netdevice_queue_work(struct netdev_event_work_cmd *cmds,
                                struct net_device *ndev)
{
        unsigned int i;
        struct netdev_event_work *ndev_work =
                kmalloc(sizeof(*ndev_work), GFP_KERNEL);

        if (!ndev_work)
                return NOTIFY_DONE;

        memcpy(ndev_work->cmds, cmds, sizeof(ndev_work->cmds));
        for (i = 0; i < ARRAY_SIZE(ndev_work->cmds) && ndev_work->cmds[i].cb; i++) {
                if (!ndev_work->cmds[i].ndev)
                        ndev_work->cmds[i].ndev = ndev;
                if (!ndev_work->cmds[i].filter_ndev)
                        ndev_work->cmds[i].filter_ndev = ndev;
                dev_hold(ndev_work->cmds[i].ndev);
                dev_hold(ndev_work->cmds[i].filter_ndev);
        }
        INIT_WORK(&ndev_work->work, netdevice_event_work_handler);

        queue_work(gid_cache_wq, &ndev_work->work);

        return NOTIFY_DONE;
}

static const struct netdev_event_work_cmd add_cmd = {
        .cb = add_netdev_ips, .filter = is_eth_port_of_netdev};
static const struct netdev_event_work_cmd add_cmd_upper_ips = {
        .cb = add_netdev_upper_ips, .filter = is_eth_port_of_netdev};

static void netdevice_event_changeupper(struct netdev_notifier_changeupper_info *changeupper_info,
                                        struct netdev_event_work_cmd *cmds)
{
        static const struct netdev_event_work_cmd upper_ips_del_cmd = {
                .cb = del_netdev_upper_ips, .filter = upper_device_filter};
        static const struct netdev_event_work_cmd bonding_default_del_cmd = {
                .cb = del_netdev_default_ips, .filter = is_eth_port_inactive_slave};

        if (changeupper_info->linking == false) {
                cmds[0] = upper_ips_del_cmd;
                cmds[0].ndev = changeupper_info->upper_dev;
                cmds[1] = add_cmd;
        } else {
                cmds[0] = bonding_default_del_cmd;
                cmds[0].ndev = changeupper_info->upper_dev;
                cmds[1] = add_cmd_upper_ips;
                cmds[1].ndev = changeupper_info->upper_dev;
                cmds[1].filter_ndev = changeupper_info->upper_dev;
        }
}

static int netdevice_event(struct notifier_block *this, unsigned long event,
                           void *ptr)
{
        static const struct netdev_event_work_cmd del_cmd = {
                .cb = del_netdev_ips, .filter = pass_all_filter};
        static const struct netdev_event_work_cmd bonding_default_del_cmd_join = {
                .cb = del_netdev_default_ips_join, .filter = is_eth_port_inactive_slave};
        static const struct netdev_event_work_cmd default_del_cmd = {
                .cb = del_netdev_default_ips, .filter = pass_all_filter};
        static const struct netdev_event_work_cmd bonding_event_ips_del_cmd = {
                .cb = del_netdev_upper_ips, .filter = upper_device_filter};
        struct net_device *ndev = netdev_notifier_info_to_dev(ptr);
        struct netdev_event_work_cmd cmds[ROCE_NETDEV_CALLBACK_SZ] = { {NULL} };

        if (ndev->type != ARPHRD_ETHER)
                return NOTIFY_DONE;

        switch (event) {
        case NETDEV_REGISTER:
        case NETDEV_UP:
                cmds[0] = bonding_default_del_cmd_join;
                cmds[1] = add_cmd;
                break;

        case NETDEV_UNREGISTER:
                if (ndev->reg_state < NETREG_UNREGISTERED)
                        cmds[0] = del_cmd;
                else
                        return NOTIFY_DONE;
                break;

        case NETDEV_CHANGEADDR:
                cmds[0] = default_del_cmd;
                cmds[1] = add_cmd;
                break;

        case NETDEV_CHANGEUPPER:
                netdevice_event_changeupper(
                        container_of(ptr, struct netdev_notifier_changeupper_info, info),
                        cmds);
                break;

        case NETDEV_BONDING_FAILOVER:
                cmds[0] = bonding_event_ips_del_cmd;
                cmds[1] = bonding_default_del_cmd_join;
                cmds[2] = add_cmd_upper_ips;
                break;

        default:
                return NOTIFY_DONE;
        }

        return netdevice_queue_work(cmds, ndev);
}

static void update_gid_event_work_handler(struct work_struct *_work)
{
        struct update_gid_event_work *work =
                container_of(_work, struct update_gid_event_work, work);

        ib_enum_all_roce_netdevs(is_eth_port_of_netdev, work->gid_attr.ndev,
                                 callback_for_addr_gid_device_scan, work);

        dev_put(work->gid_attr.ndev);
        kfree(work);
}

static int addr_event(struct notifier_block *this, unsigned long event,
                      struct sockaddr *sa, struct net_device *ndev)
{
        struct update_gid_event_work *work;
        enum gid_op_type gid_op;

        if (ndev->type != ARPHRD_ETHER)
                return NOTIFY_DONE;

        switch (event) {
        case NETDEV_UP:
                gid_op = GID_ADD;
                break;

        case NETDEV_DOWN:
                gid_op = GID_DEL;
                break;

        default:
                return NOTIFY_DONE;
        }

        work = kmalloc(sizeof(*work), GFP_ATOMIC);
        if (!work)
                return NOTIFY_DONE;

        INIT_WORK(&work->work, update_gid_event_work_handler);

        rdma_ip2gid(sa, &work->gid);
        work->gid_op = gid_op;

        memset(&work->gid_attr, 0, sizeof(work->gid_attr));
        dev_hold(ndev);
        work->gid_attr.ndev   = ndev;

        queue_work(gid_cache_wq, &work->work);

        return NOTIFY_DONE;
}

static int inetaddr_event(struct notifier_block *this, unsigned long event,
                          void *ptr)
{
        struct sockaddr_in      in;
        struct net_device       *ndev;
        struct in_ifaddr        *ifa = ptr;

        in.sin_family = AF_INET;
        in.sin_addr.s_addr = ifa->ifa_address;
        ndev = ifa->ifa_dev->dev;

        return addr_event(this, event, (struct sockaddr *)&in, ndev);
}

static int inet6addr_event(struct notifier_block *this, unsigned long event,
                           void *ptr)
{
        struct sockaddr_in6     in6;
        struct net_device       *ndev;
        struct inet6_ifaddr     *ifa6 = ptr;

        in6.sin6_family = AF_INET6;
        in6.sin6_addr = ifa6->addr;
        ndev = ifa6->idev->dev;

        return addr_event(this, event, (struct sockaddr *)&in6, ndev);
}

static struct notifier_block nb_netdevice = {
        .notifier_call = netdevice_event
};

static struct notifier_block nb_inetaddr = {
        .notifier_call = inetaddr_event
};

static struct notifier_block nb_inet6addr = {
        .notifier_call = inet6addr_event
};

int __init roce_gid_mgmt_init(void)
{
        gid_cache_wq = alloc_ordered_workqueue("gid-cache-wq", 0);
        if (!gid_cache_wq)
                return -ENOMEM;

        register_inetaddr_notifier(&nb_inetaddr);
        if (IS_ENABLED(CONFIG_IPV6))
                register_inet6addr_notifier(&nb_inet6addr);
        /* We relay on the netdevice notifier to enumerate all
         * existing devices in the system. Register to this notifier
         * last to make sure we will not miss any IP add/del
         * callbacks.
         */
        register_netdevice_notifier(&nb_netdevice);

        return 0;
}

void __exit roce_gid_mgmt_cleanup(void)
{
        if (IS_ENABLED(CONFIG_IPV6))
                unregister_inet6addr_notifier(&nb_inet6addr);
        unregister_inetaddr_notifier(&nb_inetaddr);
        unregister_netdevice_notifier(&nb_netdevice);
        /* Ensure all gid deletion tasks complete before we go down,
         * to avoid any reference to free'd memory. By the time
         * ib-core is removed, all physical devices have been removed,
         * so no issue with remaining hardware contexts.
         */
        destroy_workqueue(gid_cache_wq);
}