/*
 * net/switchdev/switchdev.c - Switch device API
 * Copyright (c) 2014-2015 Jiri Pirko <jiri@resnulli.us>
 * Copyright (c) 2014-2015 Scott Feldman <sfeldma@gmail.com>
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2 of the License, or
 * (at your option) any later version.
 */

#include <linux/kernel.h>
#include <linux/types.h>
#include <linux/init.h>
#include <linux/mutex.h>
#include <linux/notifier.h>
#include <linux/netdevice.h>
#include <linux/etherdevice.h>
#include <linux/if_bridge.h>
#include <linux/list.h>
#include <linux/workqueue.h>
#include <linux/if_vlan.h>
#include <linux/rtnetlink.h>
#include <net/ip_fib.h>
#include <net/switchdev.h>

/**
 *      switchdev_trans_item_enqueue - Enqueue data item to transaction queue
 *
 *      @trans: transaction
 *      @data: pointer to data being queued
 *      @destructor: data destructor
 *      @tritem: transaction item being queued
 *
 *      Enqeueue data item to transaction queue. tritem is typically placed in
 *      cointainter pointed at by data pointer. Destructor is called on
 *      transaction abort and after successful commit phase in case
 *      the caller did not dequeue the item before.
 */
void switchdev_trans_item_enqueue(struct switchdev_trans *trans,
                                  void *data, void (*destructor)(void const *),
                                  struct switchdev_trans_item *tritem)
{
        tritem->data = data;
        tritem->destructor = destructor;
        list_add_tail(&tritem->list, &trans->item_list);
}
EXPORT_SYMBOL_GPL(switchdev_trans_item_enqueue);

static struct switchdev_trans_item *
__switchdev_trans_item_dequeue(struct switchdev_trans *trans)
{
        struct switchdev_trans_item *tritem;

        if (list_empty(&trans->item_list))
                return NULL;
        tritem = list_first_entry(&trans->item_list,
                                  struct switchdev_trans_item, list);
        list_del(&tritem->list);
        return tritem;
}

/**
 *      switchdev_trans_item_dequeue - Dequeue data item from transaction queue
 *
 *      @trans: transaction
 */
void *switchdev_trans_item_dequeue(struct switchdev_trans *trans)
{
        struct switchdev_trans_item *tritem;

        tritem = __switchdev_trans_item_dequeue(trans);
        BUG_ON(!tritem);
        return tritem->data;
}
EXPORT_SYMBOL_GPL(switchdev_trans_item_dequeue);

static void switchdev_trans_init(struct switchdev_trans *trans)
{
        INIT_LIST_HEAD(&trans->item_list);
}

static void switchdev_trans_items_destroy(struct switchdev_trans *trans)
{
        struct switchdev_trans_item *tritem;

        while ((tritem = __switchdev_trans_item_dequeue(trans)))
                tritem->destructor(tritem->data);
}

static void switchdev_trans_items_warn_destroy(struct net_device *dev,
                                               struct switchdev_trans *trans)
{
        WARN(!list_empty(&trans->item_list), "%s: transaction item queue is not empty.\n",
             dev->name);
        switchdev_trans_items_destroy(trans);
}

static LIST_HEAD(deferred);
static DEFINE_SPINLOCK(deferred_lock);

typedef void switchdev_deferred_func_t(struct net_device *dev,
                                       const void *data);

struct switchdev_deferred_item {
        struct list_head list;
        struct net_device *dev;
        switchdev_deferred_func_t *func;
        unsigned long data[0];
};

static struct switchdev_deferred_item *switchdev_deferred_dequeue(void)
{
        struct switchdev_deferred_item *dfitem;

        spin_lock_bh(&deferred_lock);
        if (list_empty(&deferred)) {
                dfitem = NULL;
                goto unlock;
        }
        dfitem = list_first_entry(&deferred,
                                  struct switchdev_deferred_item, list);
        list_del(&dfitem->list);
unlock:
        spin_unlock_bh(&deferred_lock);
        return dfitem;
}

/**
 *      switchdev_deferred_process - Process ops in deferred queue
 *
 *      Called to flush the ops currently queued in deferred ops queue.
 *      rtnl_lock must be held.
 */
void switchdev_deferred_process(void)
{
        struct switchdev_deferred_item *dfitem;

        ASSERT_RTNL();

        while ((dfitem = switchdev_deferred_dequeue())) {
                dfitem->func(dfitem->dev, dfitem->data);
                dev_put(dfitem->dev);
                kfree(dfitem);
        }
}
EXPORT_SYMBOL_GPL(switchdev_deferred_process);

static void switchdev_deferred_process_work(struct work_struct *work)
{
        rtnl_lock();
        switchdev_deferred_process();
        rtnl_unlock();
}

static DECLARE_WORK(deferred_process_work, switchdev_deferred_process_work);

static int switchdev_deferred_enqueue(struct net_device *dev,
                                      const void *data, size_t data_len,
                                      switchdev_deferred_func_t *func)
{
        struct switchdev_deferred_item *dfitem;

        dfitem = kmalloc(sizeof(*dfitem) + data_len, GFP_ATOMIC);
        if (!dfitem)
                return -ENOMEM;
        dfitem->dev = dev;
        dfitem->func = func;
        memcpy(dfitem->data, data, data_len);
        dev_hold(dev);
        spin_lock_bh(&deferred_lock);
        list_add_tail(&dfitem->list, &deferred);
        spin_unlock_bh(&deferred_lock);
        schedule_work(&deferred_process_work);
        return 0;
}

/**
 *      switchdev_port_attr_get - Get port attribute
 *
 *      @dev: port device
 *      @attr: attribute to get
 */
int switchdev_port_attr_get(struct net_device *dev, struct switchdev_attr *attr)
{
        const struct switchdev_ops *ops = dev->switchdev_ops;
        struct net_device *lower_dev;
        struct list_head *iter;
        struct switchdev_attr first = {
                .id = SWITCHDEV_ATTR_ID_UNDEFINED
        };
        int err = -EOPNOTSUPP;

        if (ops && ops->switchdev_port_attr_get)
                return ops->switchdev_port_attr_get(dev, attr);

        if (attr->flags & SWITCHDEV_F_NO_RECURSE)
                return err;

        /* Switch device port(s) may be stacked under
         * bond/team/vlan dev, so recurse down to get attr on
         * each port.  Return -ENODATA if attr values don't
         * compare across ports.
         */

        netdev_for_each_lower_dev(dev, lower_dev, iter) {
                err = switchdev_port_attr_get(lower_dev, attr);
                if (err)
                        break;
                if (first.id == SWITCHDEV_ATTR_ID_UNDEFINED)
                        first = *attr;
                else if (memcmp(&first, attr, sizeof(*attr)))
                        return -ENODATA;
        }

        return err;
}
EXPORT_SYMBOL_GPL(switchdev_port_attr_get);

static int __switchdev_port_attr_set(struct net_device *dev,
                                     const struct switchdev_attr *attr,
                                     struct switchdev_trans *trans)
{
        const struct switchdev_ops *ops = dev->switchdev_ops;
        struct net_device *lower_dev;
        struct list_head *iter;
        int err = -EOPNOTSUPP;

        if (ops && ops->switchdev_port_attr_set) {
                err = ops->switchdev_port_attr_set(dev, attr, trans);
                goto done;
        }

        if (attr->flags & SWITCHDEV_F_NO_RECURSE)
                goto done;

        /* Switch device port(s) may be stacked under
         * bond/team/vlan dev, so recurse down to set attr on
         * each port.
         */

        netdev_for_each_lower_dev(dev, lower_dev, iter) {
                err = __switchdev_port_attr_set(lower_dev, attr, trans);
                if (err)
                        break;
        }

done:
        if (err == -EOPNOTSUPP && attr->flags & SWITCHDEV_F_SKIP_EOPNOTSUPP)
                err = 0;

        return err;
}

static int switchdev_port_attr_set_now(struct net_device *dev,
                                       const struct switchdev_attr *attr)
{
        struct switchdev_trans trans;
        int err;

        switchdev_trans_init(&trans);

        /* Phase I: prepare for attr set. Driver/device should fail
         * here if there are going to be issues in the commit phase,
         * such as lack of resources or support.  The driver/device
         * should reserve resources needed for the commit phase here,
         * but should not commit the attr.
         */

        trans.ph_prepare = true;
        err = __switchdev_port_attr_set(dev, attr, &trans);
        if (err) {
                /* Prepare phase failed: abort the transaction.  Any
                 * resources reserved in the prepare phase are
                 * released.
                 */

                if (err != -EOPNOTSUPP)
                        switchdev_trans_items_destroy(&trans);

                return err;
        }

        /* Phase II: commit attr set.  This cannot fail as a fault
         * of driver/device.  If it does, it's a bug in the driver/device
         * because the driver said everythings was OK in phase I.
         */

        trans.ph_prepare = false;
        err = __switchdev_port_attr_set(dev, attr, &trans);
        WARN(err, "%s: Commit of attribute (id=%d) failed.\n",
             dev->name, attr->id);
        switchdev_trans_items_warn_destroy(dev, &trans);

        return err;
}

static void switchdev_port_attr_set_deferred(struct net_device *dev,
                                             const void *data)
{
        const struct switchdev_attr *attr = data;
        int err;

        err = switchdev_port_attr_set_now(dev, attr);
        if (err && err != -EOPNOTSUPP)
                netdev_err(dev, "failed (err=%d) to set attribute (id=%d)\n",
                           err, attr->id);
        if (attr->complete)
                attr->complete(dev, err, attr->complete_priv);
}

static int switchdev_port_attr_set_defer(struct net_device *dev,
                                         const struct switchdev_attr *attr)
{
        return switchdev_deferred_enqueue(dev, attr, sizeof(*attr),
                                          switchdev_port_attr_set_deferred);
}

/**
 *      switchdev_port_attr_set - Set port attribute
 *
 *      @dev: port device
 *      @attr: attribute to set
 *
 *      Use a 2-phase prepare-commit transaction model to ensure
 *      system is not left in a partially updated state due to
 *      failure from driver/device.
 *
 *      rtnl_lock must be held and must not be in atomic section,
 *      in case SWITCHDEV_F_DEFER flag is not set.
 */
int switchdev_port_attr_set(struct net_device *dev,
                            const struct switchdev_attr *attr)
{
        if (attr->flags & SWITCHDEV_F_DEFER)
                return switchdev_port_attr_set_defer(dev, attr);
        ASSERT_RTNL();
        return switchdev_port_attr_set_now(dev, attr);
}
EXPORT_SYMBOL_GPL(switchdev_port_attr_set);

static size_t switchdev_obj_size(const struct switchdev_obj *obj)
{
        switch (obj->id) {
        case SWITCHDEV_OBJ_ID_PORT_VLAN:
                return sizeof(struct switchdev_obj_port_vlan);
        case SWITCHDEV_OBJ_ID_IPV4_FIB:
                return sizeof(struct switchdev_obj_ipv4_fib);
        case SWITCHDEV_OBJ_ID_PORT_FDB:
                return sizeof(struct switchdev_obj_port_fdb);
        case SWITCHDEV_OBJ_ID_PORT_MDB:
                return sizeof(struct switchdev_obj_port_mdb);
        default:
                BUG();
        }
        return 0;
}

static int __switchdev_port_obj_add(struct net_device *dev,
                                    const struct switchdev_obj *obj,
                                    struct switchdev_trans *trans)
{
        const struct switchdev_ops *ops = dev->switchdev_ops;
        struct net_device *lower_dev;
        struct list_head *iter;
        int err = -EOPNOTSUPP;

        if (ops && ops->switchdev_port_obj_add)
                return ops->switchdev_port_obj_add(dev, obj, trans);

        /* Switch device port(s) may be stacked under
         * bond/team/vlan dev, so recurse down to add object on
         * each port.
         */

        netdev_for_each_lower_dev(dev, lower_dev, iter) {
                err = __switchdev_port_obj_add(lower_dev, obj, trans);
                if (err)
                        break;
        }

        return err;
}

static int switchdev_port_obj_add_now(struct net_device *dev,
                                      const struct switchdev_obj *obj)
{
        struct switchdev_trans trans;
        int err;

        ASSERT_RTNL();

        switchdev_trans_init(&trans);

        /* Phase I: prepare for obj add. Driver/device should fail
         * here if there are going to be issues in the commit phase,
         * such as lack of resources or support.  The driver/device
         * should reserve resources needed for the commit phase here,
         * but should not commit the obj.
         */

        trans.ph_prepare = true;
        err = __switchdev_port_obj_add(dev, obj, &trans);
        if (err) {
                /* Prepare phase failed: abort the transaction.  Any
                 * resources reserved in the prepare phase are
                 * released.
                 */

                if (err != -EOPNOTSUPP)
                        switchdev_trans_items_destroy(&trans);

                return err;
        }

        /* Phase II: commit obj add.  This cannot fail as a fault
         * of driver/device.  If it does, it's a bug in the driver/device
         * because the driver said everythings was OK in phase I.
         */

        trans.ph_prepare = false;
        err = __switchdev_port_obj_add(dev, obj, &trans);
        WARN(err, "%s: Commit of object (id=%d) failed.\n", dev->name, obj->id);
        switchdev_trans_items_warn_destroy(dev, &trans);

        return err;
}

static void switchdev_port_obj_add_deferred(struct net_device *dev,
                                            const void *data)
{
        const struct switchdev_obj *obj = data;
        int err;

        err = switchdev_port_obj_add_now(dev, obj);
        if (err && err != -EOPNOTSUPP)
                netdev_err(dev, "failed (err=%d) to add object (id=%d)\n",
                           err, obj->id);
        if (obj->complete)
                obj->complete(dev, err, obj->complete_priv);
}

static int switchdev_port_obj_add_defer(struct net_device *dev,
                                        const struct switchdev_obj *obj)
{
        return switchdev_deferred_enqueue(dev, obj, switchdev_obj_size(obj),
                                          switchdev_port_obj_add_deferred);
}

/**
 *      switchdev_port_obj_add - Add port object
 *
 *      @dev: port device
 *      @id: object ID
 *      @obj: object to add
 *
 *      Use a 2-phase prepare-commit transaction model to ensure
 *      system is not left in a partially updated state due to
 *      failure from driver/device.
 *
 *      rtnl_lock must be held and must not be in atomic section,
 *      in case SWITCHDEV_F_DEFER flag is not set.
 */
int switchdev_port_obj_add(struct net_device *dev,
                           const struct switchdev_obj *obj)
{
        if (obj->flags & SWITCHDEV_F_DEFER)
                return switchdev_port_obj_add_defer(dev, obj);
        ASSERT_RTNL();
        return switchdev_port_obj_add_now(dev, obj);
}
EXPORT_SYMBOL_GPL(switchdev_port_obj_add);

static int switchdev_port_obj_del_now(struct net_device *dev,
                                      const struct switchdev_obj *obj)
{
        const struct switchdev_ops *ops = dev->switchdev_ops;
        struct net_device *lower_dev;
        struct list_head *iter;
        int err = -EOPNOTSUPP;

        if (ops && ops->switchdev_port_obj_del)
                return ops->switchdev_port_obj_del(dev, obj);

        /* Switch device port(s) may be stacked under
         * bond/team/vlan dev, so recurse down to delete object on
         * each port.
         */

        netdev_for_each_lower_dev(dev, lower_dev, iter) {
                err = switchdev_port_obj_del_now(lower_dev, obj);
                if (err)
                        break;
        }

        return err;
}

static void switchdev_port_obj_del_deferred(struct net_device *dev,
                                            const void *data)
{
        const struct switchdev_obj *obj = data;
        int err;

        err = switchdev_port_obj_del_now(dev, obj);
        if (err && err != -EOPNOTSUPP)
                netdev_err(dev, "failed (err=%d) to del object (id=%d)\n",
                           err, obj->id);
        if (obj->complete)
                obj->complete(dev, err, obj->complete_priv);
}

static int switchdev_port_obj_del_defer(struct net_device *dev,
                                        const struct switchdev_obj *obj)
{
        return switchdev_deferred_enqueue(dev, obj, switchdev_obj_size(obj),
                                          switchdev_port_obj_del_deferred);
}

/**
 *      switchdev_port_obj_del - Delete port object
 *
 *      @dev: port device
 *      @id: object ID
 *      @obj: object to delete
 *
 *      rtnl_lock must be held and must not be in atomic section,
 *      in case SWITCHDEV_F_DEFER flag is not set.
 */
int switchdev_port_obj_del(struct net_device *dev,
                           const struct switchdev_obj *obj)
{
        if (obj->flags & SWITCHDEV_F_DEFER)
                return switchdev_port_obj_del_defer(dev, obj);
        ASSERT_RTNL();
        return switchdev_port_obj_del_now(dev, obj);
}
EXPORT_SYMBOL_GPL(switchdev_port_obj_del);

/**
 *      switchdev_port_obj_dump - Dump port objects
 *
 *      @dev: port device
 *      @id: object ID
 *      @obj: object to dump
 *      @cb: function to call with a filled object
 *
 *      rtnl_lock must be held.
 */
int switchdev_port_obj_dump(struct net_device *dev, struct switchdev_obj *obj,
                            switchdev_obj_dump_cb_t *cb)
{
        const struct switchdev_ops *ops = dev->switchdev_ops;
        struct net_device *lower_dev;
        struct list_head *iter;
        int err = -EOPNOTSUPP;

        ASSERT_RTNL();

        if (ops && ops->switchdev_port_obj_dump)
                return ops->switchdev_port_obj_dump(dev, obj, cb);

        /* Switch device port(s) may be stacked under
         * bond/team/vlan dev, so recurse down to dump objects on
         * first port at bottom of stack.
         */

        netdev_for_each_lower_dev(dev, lower_dev, iter) {
                err = switchdev_port_obj_dump(lower_dev, obj, cb);
                break;
        }

        return err;
}
EXPORT_SYMBOL_GPL(switchdev_port_obj_dump);

static RAW_NOTIFIER_HEAD(switchdev_notif_chain);

/**
 *      register_switchdev_notifier - Register notifier
 *      @nb: notifier_block
 *
 *      Register switch device notifier. This should be used by code
 *      which needs to monitor events happening in particular device.
 *      Return values are same as for atomic_notifier_chain_register().
 */
int register_switchdev_notifier(struct notifier_block *nb)
{
        int err;

        rtnl_lock();
        err = raw_notifier_chain_register(&switchdev_notif_chain, nb);
        rtnl_unlock();
        return err;
}
EXPORT_SYMBOL_GPL(register_switchdev_notifier);

/**
 *      unregister_switchdev_notifier - Unregister notifier
 *      @nb: notifier_block
 *
 *      Unregister switch device notifier.
 *      Return values are same as for atomic_notifier_chain_unregister().
 */
int unregister_switchdev_notifier(struct notifier_block *nb)
{
        int err;

        rtnl_lock();
        err = raw_notifier_chain_unregister(&switchdev_notif_chain, nb);
        rtnl_unlock();
        return err;
}
EXPORT_SYMBOL_GPL(unregister_switchdev_notifier);

/**
 *      call_switchdev_notifiers - Call notifiers
 *      @val: value passed unmodified to notifier function
 *      @dev: port device
 *      @info: notifier information data
 *
 *      Call all network notifier blocks. This should be called by driver
 *      when it needs to propagate hardware event.
 *      Return values are same as for atomic_notifier_call_chain().
 *      rtnl_lock must be held.
 */
int call_switchdev_notifiers(unsigned long val, struct net_device *dev,
                             struct switchdev_notifier_info *info)
{
        int err;

        ASSERT_RTNL();

        info->dev = dev;
        err = raw_notifier_call_chain(&switchdev_notif_chain, val, info);
        return err;
}
EXPORT_SYMBOL_GPL(call_switchdev_notifiers);

struct switchdev_vlan_dump {
        struct switchdev_obj_port_vlan vlan;
        struct sk_buff *skb;
        u32 filter_mask;
        u16 flags;
        u16 begin;
        u16 end;
};

static int switchdev_port_vlan_dump_put(struct switchdev_vlan_dump *dump)
{
        struct bridge_vlan_info vinfo;

        vinfo.flags = dump->flags;

        if (dump->begin == 0 && dump->end == 0) {
                return 0;
        } else if (dump->begin == dump->end) {
                vinfo.vid = dump->begin;
                if (nla_put(dump->skb, IFLA_BRIDGE_VLAN_INFO,
                            sizeof(vinfo), &vinfo))
                        return -EMSGSIZE;
        } else {
                vinfo.vid = dump->begin;
                vinfo.flags |= BRIDGE_VLAN_INFO_RANGE_BEGIN;
                if (nla_put(dump->skb, IFLA_BRIDGE_VLAN_INFO,
                            sizeof(vinfo), &vinfo))
                        return -EMSGSIZE;
                vinfo.vid = dump->end;
                vinfo.flags &= ~BRIDGE_VLAN_INFO_RANGE_BEGIN;
                vinfo.flags |= BRIDGE_VLAN_INFO_RANGE_END;
                if (nla_put(dump->skb, IFLA_BRIDGE_VLAN_INFO,
                            sizeof(vinfo), &vinfo))
                        return -EMSGSIZE;
        }

        return 0;
}

static int switchdev_port_vlan_dump_cb(struct switchdev_obj *obj)
{
        struct switchdev_obj_port_vlan *vlan = SWITCHDEV_OBJ_PORT_VLAN(obj);
        struct switchdev_vlan_dump *dump =
                container_of(vlan, struct switchdev_vlan_dump, vlan);
        int err = 0;

        if (vlan->vid_begin > vlan->vid_end)
                return -EINVAL;

        if (dump->filter_mask & RTEXT_FILTER_BRVLAN) {
                dump->flags = vlan->flags;
                for (dump->begin = dump->end = vlan->vid_begin;
                     dump->begin <= vlan->vid_end;
                     dump->begin++, dump->end++) {
                        err = switchdev_port_vlan_dump_put(dump);
                        if (err)
                                return err;
                }
        } else if (dump->filter_mask & RTEXT_FILTER_BRVLAN_COMPRESSED) {
                if (dump->begin > vlan->vid_begin &&
                    dump->begin >= vlan->vid_end) {
                        if ((dump->begin - 1) == vlan->vid_end &&
                            dump->flags == vlan->flags) {
                                /* prepend */
                                dump->begin = vlan->vid_begin;
                        } else {
                                err = switchdev_port_vlan_dump_put(dump);
                                dump->flags = vlan->flags;
                                dump->begin = vlan->vid_begin;
                                dump->end = vlan->vid_end;
                        }
                } else if (dump->end <= vlan->vid_begin &&
                           dump->end < vlan->vid_end) {
                        if ((dump->end  + 1) == vlan->vid_begin &&
                            dump->flags == vlan->flags) {
                                /* append */
                                dump->end = vlan->vid_end;
                        } else {
                                err = switchdev_port_vlan_dump_put(dump);
                                dump->flags = vlan->flags;
                                dump->begin = vlan->vid_begin;
                                dump->end = vlan->vid_end;
                        }
                } else {
                        err = -EINVAL;
                }
        }

        return err;
}

static int switchdev_port_vlan_fill(struct sk_buff *skb, struct net_device *dev,
                                    u32 filter_mask)
{
        struct switchdev_vlan_dump dump = {
                .vlan.obj.orig_dev = dev,
                .vlan.obj.id = SWITCHDEV_OBJ_ID_PORT_VLAN,
                .skb = skb,
                .filter_mask = filter_mask,
        };
        int err = 0;

        if ((filter_mask & RTEXT_FILTER_BRVLAN) ||
            (filter_mask & RTEXT_FILTER_BRVLAN_COMPRESSED)) {
                err = switchdev_port_obj_dump(dev, &dump.vlan.obj,
                                              switchdev_port_vlan_dump_cb);
                if (err)
                        goto err_out;
                if (filter_mask & RTEXT_FILTER_BRVLAN_COMPRESSED)
                        /* last one */
                        err = switchdev_port_vlan_dump_put(&dump);
        }

err_out:
        return err == -EOPNOTSUPP ? 0 : err;
}

/**
 *      switchdev_port_bridge_getlink - Get bridge port attributes
 *
 *      @dev: port device
 *
 *      Called for SELF on rtnl_bridge_getlink to get bridge port
 *      attributes.
 */
int switchdev_port_bridge_getlink(struct sk_buff *skb, u32 pid, u32 seq,
                                  struct net_device *dev, u32 filter_mask,
                                  int nlflags)
{
        struct switchdev_attr attr = {
                .orig_dev = dev,
                .id = SWITCHDEV_ATTR_ID_PORT_BRIDGE_FLAGS,
        };
        u16 mode = BRIDGE_MODE_UNDEF;
        u32 mask = BR_LEARNING | BR_LEARNING_SYNC | BR_FLOOD;
        int err;

        err = switchdev_port_attr_get(dev, &attr);
        if (err && err != -EOPNOTSUPP)
                return err;

        return ndo_dflt_bridge_getlink(skb, pid, seq, dev, mode,
                                       attr.u.brport_flags, mask, nlflags,
                                       filter_mask, switchdev_port_vlan_fill);
}
EXPORT_SYMBOL_GPL(switchdev_port_bridge_getlink);

static int switchdev_port_br_setflag(struct net_device *dev,
                                     struct nlattr *nlattr,
                                     unsigned long brport_flag)
{
        struct switchdev_attr attr = {
                .orig_dev = dev,
                .id = SWITCHDEV_ATTR_ID_PORT_BRIDGE_FLAGS,
        };
        u8 flag = nla_get_u8(nlattr);
        int err;

        err = switchdev_port_attr_get(dev, &attr);
        if (err)
                return err;

        if (flag)
                attr.u.brport_flags |= brport_flag;
        else
                attr.u.brport_flags &= ~brport_flag;

        return switchdev_port_attr_set(dev, &attr);
}

static const struct nla_policy
switchdev_port_bridge_policy[IFLA_BRPORT_MAX + 1] = {
        [IFLA_BRPORT_STATE]             = { .type = NLA_U8 },
        [IFLA_BRPORT_COST]              = { .type = NLA_U32 },
        [IFLA_BRPORT_PRIORITY]          = { .type = NLA_U16 },
        [IFLA_BRPORT_MODE]              = { .type = NLA_U8 },
        [IFLA_BRPORT_GUARD]             = { .type = NLA_U8 },
        [IFLA_BRPORT_PROTECT]           = { .type = NLA_U8 },
        [IFLA_BRPORT_FAST_LEAVE]        = { .type = NLA_U8 },
        [IFLA_BRPORT_LEARNING]          = { .type = NLA_U8 },
        [IFLA_BRPORT_LEARNING_SYNC]     = { .type = NLA_U8 },
        [IFLA_BRPORT_UNICAST_FLOOD]     = { .type = NLA_U8 },
};

static int switchdev_port_br_setlink_protinfo(struct net_device *dev,
                                              struct nlattr *protinfo)
{
        struct nlattr *attr;
        int rem;
        int err;

        err = nla_validate_nested(protinfo, IFLA_BRPORT_MAX,
                                  switchdev_port_bridge_policy);
        if (err)
                return err;

        nla_for_each_nested(attr, protinfo, rem) {
                switch (nla_type(attr)) {
                case IFLA_BRPORT_LEARNING:
                        err = switchdev_port_br_setflag(dev, attr,
                                                        BR_LEARNING);
                        break;
                case IFLA_BRPORT_LEARNING_SYNC:
                        err = switchdev_port_br_setflag(dev, attr,
                                                        BR_LEARNING_SYNC);
                        break;
                case IFLA_BRPORT_UNICAST_FLOOD:
                        err = switchdev_port_br_setflag(dev, attr, BR_FLOOD);
                        break;
                default:
                        err = -EOPNOTSUPP;
                        break;
                }
                if (err)
                        return err;
        }

        return 0;
}

static int switchdev_port_br_afspec(struct net_device *dev,
                                    struct nlattr *afspec,
                                    int (*f)(struct net_device *dev,
                                             const struct switchdev_obj *obj))
{
        struct nlattr *attr;
        struct bridge_vlan_info *vinfo;
        struct switchdev_obj_port_vlan vlan = {
                .obj.orig_dev = dev,
                .obj.id = SWITCHDEV_OBJ_ID_PORT_VLAN,
        };
        int rem;
        int err;

        nla_for_each_nested(attr, afspec, rem) {
                if (nla_type(attr) != IFLA_BRIDGE_VLAN_INFO)
                        continue;
                if (nla_len(attr) != sizeof(struct bridge_vlan_info))
                        return -EINVAL;
                vinfo = nla_data(attr);
                if (!vinfo->vid || vinfo->vid >= VLAN_VID_MASK)
                        return -EINVAL;
                vlan.flags = vinfo->flags;
                if (vinfo->flags & BRIDGE_VLAN_INFO_RANGE_BEGIN) {
                        if (vlan.vid_begin)
                                return -EINVAL;
                        vlan.vid_begin = vinfo->vid;
                        /* don't allow range of pvids */
                        if (vlan.flags & BRIDGE_VLAN_INFO_PVID)
                                return -EINVAL;
                } else if (vinfo->flags & BRIDGE_VLAN_INFO_RANGE_END) {
                        if (!vlan.vid_begin)
                                return -EINVAL;
                        vlan.vid_end = vinfo->vid;
                        if (vlan.vid_end <= vlan.vid_begin)
                                return -EINVAL;
                        err = f(dev, &vlan.obj);
                        if (err)
                                return err;
                        vlan.vid_begin = 0;
                } else {
                        if (vlan.vid_begin)
                                return -EINVAL;
                        vlan.vid_begin = vinfo->vid;
                        vlan.vid_end = vinfo->vid;
                        err = f(dev, &vlan.obj);
                        if (err)
                                return err;
                        vlan.vid_begin = 0;
                }
        }

        return 0;
}

/**
 *      switchdev_port_bridge_setlink - Set bridge port attributes
 *
 *      @dev: port device
 *      @nlh: netlink header
 *      @flags: netlink flags
 *
 *      Called for SELF on rtnl_bridge_setlink to set bridge port
 *      attributes.
 */
int switchdev_port_bridge_setlink(struct net_device *dev,
                                  struct nlmsghdr *nlh, u16 flags)
{
        struct nlattr *protinfo;
        struct nlattr *afspec;
        int err = 0;

        protinfo = nlmsg_find_attr(nlh, sizeof(struct ifinfomsg),
                                   IFLA_PROTINFO);
        if (protinfo) {
                err = switchdev_port_br_setlink_protinfo(dev, protinfo);
                if (err)
                        return err;
        }

        afspec = nlmsg_find_attr(nlh, sizeof(struct ifinfomsg),
                                 IFLA_AF_SPEC);
        if (afspec)
                err = switchdev_port_br_afspec(dev, afspec,
                                               switchdev_port_obj_add);

        return err;
}
EXPORT_SYMBOL_GPL(switchdev_port_bridge_setlink);

/**
 *      switchdev_port_bridge_dellink - Set bridge port attributes
 *
 *      @dev: port device
 *      @nlh: netlink header
 *      @flags: netlink flags
 *
 *      Called for SELF on rtnl_bridge_dellink to set bridge port
 *      attributes.
 */
int switchdev_port_bridge_dellink(struct net_device *dev,
                                  struct nlmsghdr *nlh, u16 flags)
{
        struct nlattr *afspec;

        afspec = nlmsg_find_attr(nlh, sizeof(struct ifinfomsg),
                                 IFLA_AF_SPEC);
        if (afspec)
                return switchdev_port_br_afspec(dev, afspec,
                                                switchdev_port_obj_del);

        return 0;
}
EXPORT_SYMBOL_GPL(switchdev_port_bridge_dellink);

/**
 *      switchdev_port_fdb_add - Add FDB (MAC/VLAN) entry to port
 *
 *      @ndmsg: netlink hdr
 *      @nlattr: netlink attributes
 *      @dev: port device
 *      @addr: MAC address to add
 *      @vid: VLAN to add
 *
 *      Add FDB entry to switch device.
 */
int switchdev_port_fdb_add(struct ndmsg *ndm, struct nlattr *tb[],
                           struct net_device *dev, const unsigned char *addr,
                           u16 vid, u16 nlm_flags)
{
        struct switchdev_obj_port_fdb fdb = {
                .obj.orig_dev = dev,
                .obj.id = SWITCHDEV_OBJ_ID_PORT_FDB,
                .vid = vid,
        };

        ether_addr_copy(fdb.addr, addr);
        return switchdev_port_obj_add(dev, &fdb.obj);
}
EXPORT_SYMBOL_GPL(switchdev_port_fdb_add);

/**
 *      switchdev_port_fdb_del - Delete FDB (MAC/VLAN) entry from port
 *
 *      @ndmsg: netlink hdr
 *      @nlattr: netlink attributes
 *      @dev: port device
 *      @addr: MAC address to delete
 *      @vid: VLAN to delete
 *
 *      Delete FDB entry from switch device.
 */
int switchdev_port_fdb_del(struct ndmsg *ndm, struct nlattr *tb[],
                           struct net_device *dev, const unsigned char *addr,
                           u16 vid)
{
        struct switchdev_obj_port_fdb fdb = {
                .obj.orig_dev = dev,
                .obj.id = SWITCHDEV_OBJ_ID_PORT_FDB,
                .vid = vid,
        };

        ether_addr_copy(fdb.addr, addr);
        return switchdev_port_obj_del(dev, &fdb.obj);
}
EXPORT_SYMBOL_GPL(switchdev_port_fdb_del);

struct switchdev_fdb_dump {
        struct switchdev_obj_port_fdb fdb;
        struct net_device *dev;
        struct sk_buff *skb;
        struct netlink_callback *cb;
        int idx;
};

static int switchdev_port_fdb_dump_cb(struct switchdev_obj *obj)
{
        struct switchdev_obj_port_fdb *fdb = SWITCHDEV_OBJ_PORT_FDB(obj);
        struct switchdev_fdb_dump *dump =
                container_of(fdb, struct switchdev_fdb_dump, fdb);
        u32 portid = NETLINK_CB(dump->cb->skb).portid;
        u32 seq = dump->cb->nlh->nlmsg_seq;
        struct nlmsghdr *nlh;
        struct ndmsg *ndm;

        if (dump->idx < dump->cb->args[0])
                goto skip;

        nlh = nlmsg_put(dump->skb, portid, seq, RTM_NEWNEIGH,
                        sizeof(*ndm), NLM_F_MULTI);
        if (!nlh)
                return -EMSGSIZE;

        ndm = nlmsg_data(nlh);
        ndm->ndm_family  = AF_BRIDGE;
        ndm->ndm_pad1    = 0;
        ndm->ndm_pad2    = 0;
        ndm->ndm_flags   = NTF_SELF;
        ndm->ndm_type    = 0;
        ndm->ndm_ifindex = dump->dev->ifindex;
        ndm->ndm_state   = fdb->ndm_state;

        if (nla_put(dump->skb, NDA_LLADDR, ETH_ALEN, fdb->addr))
                goto nla_put_failure;

        if (fdb->vid && nla_put_u16(dump->skb, NDA_VLAN, fdb->vid))
                goto nla_put_failure;

        nlmsg_end(dump->skb, nlh);

skip:
        dump->idx++;
        return 0;

nla_put_failure:
        nlmsg_cancel(dump->skb, nlh);
        return -EMSGSIZE;
}

/**
 *      switchdev_port_fdb_dump - Dump port FDB (MAC/VLAN) entries
 *
 *      @skb: netlink skb
 *      @cb: netlink callback
 *      @dev: port device
 *      @filter_dev: filter device
 *      @idx:
 *
 *      Dump FDB entries from switch device.
 */
int switchdev_port_fdb_dump(struct sk_buff *skb, struct netlink_callback *cb,
                            struct net_device *dev,
                            struct net_device *filter_dev, int idx)
{
        struct switchdev_fdb_dump dump = {
                .fdb.obj.orig_dev = dev,
                .fdb.obj.id = SWITCHDEV_OBJ_ID_PORT_FDB,
                .dev = dev,
                .skb = skb,
                .cb = cb,
                .idx = idx,
        };
        int err;

        err = switchdev_port_obj_dump(dev, &dump.fdb.obj,
                                      switchdev_port_fdb_dump_cb);
        cb->args[1] = err;
        return dump.idx;
}
EXPORT_SYMBOL_GPL(switchdev_port_fdb_dump);

static struct net_device *switchdev_get_lowest_dev(struct net_device *dev)
{
        const struct switchdev_ops *ops = dev->switchdev_ops;
        struct net_device *lower_dev;
        struct net_device *port_dev;
        struct list_head *iter;

        /* Recusively search down until we find a sw port dev.
         * (A sw port dev supports switchdev_port_attr_get).
         */

        if (ops && ops->switchdev_port_attr_get)
                return dev;

        netdev_for_each_lower_dev(dev, lower_dev, iter) {
                port_dev = switchdev_get_lowest_dev(lower_dev);
                if (port_dev)
                        return port_dev;
        }

        return NULL;
}

static struct net_device *switchdev_get_dev_by_nhs(struct fib_info *fi)
{
        struct switchdev_attr attr = {
                .id = SWITCHDEV_ATTR_ID_PORT_PARENT_ID,
        };
        struct switchdev_attr prev_attr;
        struct net_device *dev = NULL;
        int nhsel;

        ASSERT_RTNL();

        /* For this route, all nexthop devs must be on the same switch. */

        for (nhsel = 0; nhsel < fi->fib_nhs; nhsel++) {
                const struct fib_nh *nh = &fi->fib_nh[nhsel];

                if (!nh->nh_dev)
                        return NULL;

                dev = switchdev_get_lowest_dev(nh->nh_dev);
                if (!dev)
                        return NULL;

                attr.orig_dev = dev;
                if (switchdev_port_attr_get(dev, &attr))
                        return NULL;

                if (nhsel > 0 &&
                    !netdev_phys_item_id_same(&prev_attr.u.ppid, &attr.u.ppid))
                                return NULL;

                prev_attr = attr;
        }

        return dev;
}

/**
 *      switchdev_fib_ipv4_add - Add/modify switch IPv4 route entry
 *
 *      @dst: route's IPv4 destination address
 *      @dst_len: destination address length (prefix length)
 *      @fi: route FIB info structure
 *      @tos: route TOS
 *      @type: route type
 *      @nlflags: netlink flags passed in (NLM_F_*)
 *      @tb_id: route table ID
 *
 *      Add/modify switch IPv4 route entry.
 */
int switchdev_fib_ipv4_add(u32 dst, int dst_len, struct fib_info *fi,
                           u8 tos, u8 type, u32 nlflags, u32 tb_id)
{
        struct switchdev_obj_ipv4_fib ipv4_fib = {
                .obj.id = SWITCHDEV_OBJ_ID_IPV4_FIB,
                .dst = dst,
                .dst_len = dst_len,
                .fi = fi,
                .tos = tos,
                .type = type,
                .nlflags = nlflags,
                .tb_id = tb_id,
        };
        struct net_device *dev;
        int err = 0;

        /* Don't offload route if using custom ip rules or if
         * IPv4 FIB offloading has been disabled completely.
         */

#ifdef CONFIG_IP_MULTIPLE_TABLES
        if (fi->fib_net->ipv4.fib_has_custom_rules)
                return 0;
#endif

        if (fi->fib_net->ipv4.fib_offload_disabled)
                return 0;

        dev = switchdev_get_dev_by_nhs(fi);
        if (!dev)
                return 0;

        ipv4_fib.obj.orig_dev = dev;
        err = switchdev_port_obj_add(dev, &ipv4_fib.obj);
        if (!err)
                fi->fib_flags |= RTNH_F_OFFLOAD;

        return err == -EOPNOTSUPP ? 0 : err;
}
EXPORT_SYMBOL_GPL(switchdev_fib_ipv4_add);

/**
 *      switchdev_fib_ipv4_del - Delete IPv4 route entry from switch
 *
 *      @dst: route's IPv4 destination address
 *      @dst_len: destination address length (prefix length)
 *      @fi: route FIB info structure
 *      @tos: route TOS
 *      @type: route type
 *      @tb_id: route table ID
 *
 *      Delete IPv4 route entry from switch device.
 */
int switchdev_fib_ipv4_del(u32 dst, int dst_len, struct fib_info *fi,
                           u8 tos, u8 type, u32 tb_id)
{
        struct switchdev_obj_ipv4_fib ipv4_fib = {
                .obj.id = SWITCHDEV_OBJ_ID_IPV4_FIB,
                .dst = dst,
                .dst_len = dst_len,
                .fi = fi,
                .tos = tos,
                .type = type,
                .nlflags = 0,
                .tb_id = tb_id,
        };
        struct net_device *dev;
        int err = 0;

        if (!(fi->fib_flags & RTNH_F_OFFLOAD))
                return 0;

        dev = switchdev_get_dev_by_nhs(fi);
        if (!dev)
                return 0;

        ipv4_fib.obj.orig_dev = dev;
        err = switchdev_port_obj_del(dev, &ipv4_fib.obj);
        if (!err)
                fi->fib_flags &= ~RTNH_F_OFFLOAD;

        return err == -EOPNOTSUPP ? 0 : err;
}
EXPORT_SYMBOL_GPL(switchdev_fib_ipv4_del);

/**
 *      switchdev_fib_ipv4_abort - Abort an IPv4 FIB operation
 *
 *      @fi: route FIB info structure
 */
void switchdev_fib_ipv4_abort(struct fib_info *fi)
{
        /* There was a problem installing this route to the offload
         * device.  For now, until we come up with more refined
         * policy handling, abruptly end IPv4 fib offloading for
         * for entire net by flushing offload device(s) of all
         * IPv4 routes, and mark IPv4 fib offloading broken from
         * this point forward.
         */

        fib_flush_external(fi->fib_net);
        fi->fib_net->ipv4.fib_offload_disabled = true;
}
EXPORT_SYMBOL_GPL(switchdev_fib_ipv4_abort);

bool switchdev_port_same_parent_id(struct net_device *a,
                                   struct net_device *b)
{
        struct switchdev_attr a_attr = {
                .orig_dev = a,
                .id = SWITCHDEV_ATTR_ID_PORT_PARENT_ID,
                .flags = SWITCHDEV_F_NO_RECURSE,
        };
        struct switchdev_attr b_attr = {
                .orig_dev = b,
                .id = SWITCHDEV_ATTR_ID_PORT_PARENT_ID,
                .flags = SWITCHDEV_F_NO_RECURSE,
        };

        if (switchdev_port_attr_get(a, &a_attr) ||
            switchdev_port_attr_get(b, &b_attr))
                return false;

        return netdev_phys_item_id_same(&a_attr.u.ppid, &b_attr.u.ppid);
}

static u32 switchdev_port_fwd_mark_get(struct net_device *dev,
                                       struct net_device *group_dev)
{
        struct net_device *lower_dev;
        struct list_head *iter;

        netdev_for_each_lower_dev(group_dev, lower_dev, iter) {
                if (lower_dev == dev)
                        continue;
                if (switchdev_port_same_parent_id(dev, lower_dev))
                        return lower_dev->offload_fwd_mark;
                return switchdev_port_fwd_mark_get(dev, lower_dev);
        }

        return dev->ifindex;
}
EXPORT_SYMBOL_GPL(switchdev_port_same_parent_id);

static void switchdev_port_fwd_mark_reset(struct net_device *group_dev,
                                          u32 old_mark, u32 *reset_mark)
{
        struct net_device *lower_dev;
        struct list_head *iter;

        netdev_for_each_lower_dev(group_dev, lower_dev, iter) {
                if (lower_dev->offload_fwd_mark == old_mark) {
                        if (!*reset_mark)
                                *reset_mark = lower_dev->ifindex;
                        lower_dev->offload_fwd_mark = *reset_mark;
                }
                switchdev_port_fwd_mark_reset(lower_dev, old_mark, reset_mark);
        }
}

/**
 *      switchdev_port_fwd_mark_set - Set port offload forwarding mark
 *
 *      @dev: port device
 *      @group_dev: containing device
 *      @joining: true if dev is joining group; false if leaving group
 *
 *      An ungrouped port's offload mark is just its ifindex.  A grouped
 *      port's (member of a bridge, for example) offload mark is the ifindex
 *      of one of the ports in the group with the same parent (switch) ID.
 *      Ports on the same device in the same group will have the same mark.
 *
 *      Example:
 *
 *              br0             ifindex=9
 *                sw1p1         ifindex=2       mark=2
 *                sw1p2         ifindex=3       mark=2
 *                sw2p1         ifindex=4       mark=5
 *                sw2p2         ifindex=5       mark=5
 *
 *      If sw2p2 leaves the bridge, we'll have:
 *
 *              br0             ifindex=9
 *                sw1p1         ifindex=2       mark=2
 *                sw1p2         ifindex=3       mark=2
 *                sw2p1         ifindex=4       mark=4
 *              sw2p2           ifindex=5       mark=5
 */
void switchdev_port_fwd_mark_set(struct net_device *dev,
                                 struct net_device *group_dev,
                                 bool joining)
{
        u32 mark = dev->ifindex;
        u32 reset_mark = 0;

        if (group_dev) {
                ASSERT_RTNL();
                if (joining)
                        mark = switchdev_port_fwd_mark_get(dev, group_dev);
                else if (dev->offload_fwd_mark == mark)
                        /* Ohoh, this port was the mark reference port,
                         * but it's leaving the group, so reset the
                         * mark for the remaining ports in the group.
                         */
                        switchdev_port_fwd_mark_reset(group_dev, mark,
                                                      &reset_mark);
        }

        dev->offload_fwd_mark = mark;
}
EXPORT_SYMBOL_GPL(switchdev_port_fwd_mark_set);