net/dsa/switch.c

root/net/dsa/switch.c
// SPDX-License-Identifier: GPL-2.0-or-later
/*
 * Handling of a single switch chip, part of a switch fabric
 *
 * Copyright (c) 2017 Savoir-faire Linux Inc.
 *      Vivien Didelot <vivien.didelot@savoirfairelinux.com>
 */

#include <linux/if_bridge.h>
#include <linux/netdevice.h>
#include <linux/notifier.h>
#include <linux/if_vlan.h>
#include <net/switchdev.h>

#include "dsa.h"
#include "netlink.h"
#include "port.h"
#include "switch.h"
#include "tag_8021q.h"
#include "trace.h"
#include "user.h"

static unsigned int dsa_switch_fastest_ageing_time(struct dsa_switch *ds,
                                                   unsigned int ageing_time)
{
        struct dsa_port *dp;

        dsa_switch_for_each_port(dp, ds)
                if (dp->ageing_time && dp->ageing_time < ageing_time)
                        ageing_time = dp->ageing_time;

        return ageing_time;
}

static int dsa_switch_ageing_time(struct dsa_switch *ds,
                                  struct dsa_notifier_ageing_time_info *info)
{
        unsigned int ageing_time = info->ageing_time;

        if (ds->ageing_time_min && ageing_time < ds->ageing_time_min)
                return -ERANGE;

        if (ds->ageing_time_max && ageing_time > ds->ageing_time_max)
                return -ERANGE;

        /* Program the fastest ageing time in case of multiple bridges */
        ageing_time = dsa_switch_fastest_ageing_time(ds, ageing_time);

        if (ds->ops->set_ageing_time)
                return ds->ops->set_ageing_time(ds, ageing_time);

        return 0;
}

static bool dsa_port_mtu_match(struct dsa_port *dp,
                               struct dsa_notifier_mtu_info *info)
{
        return dp == info->dp || dsa_port_is_dsa(dp) || dsa_port_is_cpu(dp);
}

static int dsa_switch_mtu(struct dsa_switch *ds,
                          struct dsa_notifier_mtu_info *info)
{
        struct dsa_port *dp;
        int ret;

        if (!ds->ops->port_change_mtu)
                return -EOPNOTSUPP;

        dsa_switch_for_each_port(dp, ds) {
                if (dsa_port_mtu_match(dp, info)) {
                        ret = ds->ops->port_change_mtu(ds, dp->index,
                                                       info->mtu);
                        if (ret)
                                return ret;
                }
        }

        return 0;
}

static int dsa_switch_bridge_join(struct dsa_switch *ds,
                                  struct dsa_notifier_bridge_info *info)
{
        int err;

        if (info->dp->ds == ds) {
                if (!ds->ops->port_bridge_join)
                        return -EOPNOTSUPP;

                err = ds->ops->port_bridge_join(ds, info->dp->index,
                                                info->bridge,
                                                &info->tx_fwd_offload,
                                                info->extack);
                if (err)
                        return err;
        }

        if (info->dp->ds != ds && ds->ops->crosschip_bridge_join) {
                err = ds->ops->crosschip_bridge_join(ds,
                                                     info->dp->ds->dst->index,
                                                     info->dp->ds->index,
                                                     info->dp->index,
                                                     info->bridge,
                                                     info->extack);
                if (err)
                        return err;
        }

        return 0;
}

static int dsa_switch_bridge_leave(struct dsa_switch *ds,
                                   struct dsa_notifier_bridge_info *info)
{
        if (info->dp->ds == ds && ds->ops->port_bridge_leave)
                ds->ops->port_bridge_leave(ds, info->dp->index, info->bridge);

        if (info->dp->ds != ds && ds->ops->crosschip_bridge_leave)
                ds->ops->crosschip_bridge_leave(ds, info->dp->ds->dst->index,
                                                info->dp->ds->index,
                                                info->dp->index,
                                                info->bridge);

        return 0;
}

/* Matches for all upstream-facing ports (the CPU port and all upstream-facing
 * DSA links) that sit between the targeted port on which the notifier was
 * emitted and its dedicated CPU port.
 */
static bool dsa_port_host_address_match(struct dsa_port *dp,
                                        const struct dsa_port *targeted_dp)
{
        struct dsa_port *cpu_dp = targeted_dp->cpu_dp;

        if (dsa_switch_is_upstream_of(dp->ds, targeted_dp->ds))
                return dp->index == dsa_towards_port(dp->ds, cpu_dp->ds->index,
                                                     cpu_dp->index);

        return false;
}

static struct dsa_mac_addr *dsa_mac_addr_find(struct list_head *addr_list,
                                              const unsigned char *addr, u16 vid,
                                              struct dsa_db db)
{
        struct dsa_mac_addr *a;

        list_for_each_entry(a, addr_list, list)
                if (ether_addr_equal(a->addr, addr) && a->vid == vid &&
                    dsa_db_equal(&a->db, &db))
                        return a;

        return NULL;
}

static int dsa_port_do_mdb_add(struct dsa_port *dp,
                               const struct switchdev_obj_port_mdb *mdb,
                               struct dsa_db db)
{
        struct dsa_switch *ds = dp->ds;
        struct dsa_mac_addr *a;
        int port = dp->index;
        int err = 0;

        /* No need to bother with refcounting for user ports */
        if (!(dsa_port_is_cpu(dp) || dsa_port_is_dsa(dp))) {
                err = ds->ops->port_mdb_add(ds, port, mdb, db);
                trace_dsa_mdb_add_hw(dp, mdb->addr, mdb->vid, &db, err);

                return err;
        }

        mutex_lock(&dp->addr_lists_lock);

        a = dsa_mac_addr_find(&dp->mdbs, mdb->addr, mdb->vid, db);
        if (a) {
                refcount_inc(&a->refcount);
                trace_dsa_mdb_add_bump(dp, mdb->addr, mdb->vid, &db,
                                       &a->refcount);
                goto out;
        }

        a = kzalloc_obj(*a);
        if (!a) {
                err = -ENOMEM;
                goto out;
        }

        err = ds->ops->port_mdb_add(ds, port, mdb, db);
        trace_dsa_mdb_add_hw(dp, mdb->addr, mdb->vid, &db, err);
        if (err) {
                kfree(a);
                goto out;
        }

        ether_addr_copy(a->addr, mdb->addr);
        a->vid = mdb->vid;
        a->db = db;
        refcount_set(&a->refcount, 1);
        list_add_tail(&a->list, &dp->mdbs);

out:
        mutex_unlock(&dp->addr_lists_lock);

        return err;
}

static int dsa_port_do_mdb_del(struct dsa_port *dp,
                               const struct switchdev_obj_port_mdb *mdb,
                               struct dsa_db db)
{
        struct dsa_switch *ds = dp->ds;
        struct dsa_mac_addr *a;
        int port = dp->index;
        int err = 0;

        /* No need to bother with refcounting for user ports */
        if (!(dsa_port_is_cpu(dp) || dsa_port_is_dsa(dp))) {
                err = ds->ops->port_mdb_del(ds, port, mdb, db);
                trace_dsa_mdb_del_hw(dp, mdb->addr, mdb->vid, &db, err);

                return err;
        }

        mutex_lock(&dp->addr_lists_lock);

        a = dsa_mac_addr_find(&dp->mdbs, mdb->addr, mdb->vid, db);
        if (!a) {
                trace_dsa_mdb_del_not_found(dp, mdb->addr, mdb->vid, &db);
                err = -ENOENT;
                goto out;
        }

        if (!refcount_dec_and_test(&a->refcount)) {
                trace_dsa_mdb_del_drop(dp, mdb->addr, mdb->vid, &db,
                                       &a->refcount);
                goto out;
        }

        err = ds->ops->port_mdb_del(ds, port, mdb, db);
        trace_dsa_mdb_del_hw(dp, mdb->addr, mdb->vid, &db, err);
        if (err) {
                refcount_set(&a->refcount, 1);
                goto out;
        }

        list_del(&a->list);
        kfree(a);

out:
        mutex_unlock(&dp->addr_lists_lock);

        return err;
}

static int dsa_port_do_fdb_add(struct dsa_port *dp, const unsigned char *addr,
                               u16 vid, struct dsa_db db)
{
        struct dsa_switch *ds = dp->ds;
        struct dsa_mac_addr *a;
        int port = dp->index;
        int err = 0;

        /* No need to bother with refcounting for user ports */
        if (!(dsa_port_is_cpu(dp) || dsa_port_is_dsa(dp))) {
                err = ds->ops->port_fdb_add(ds, port, addr, vid, db);
                trace_dsa_fdb_add_hw(dp, addr, vid, &db, err);

                return err;
        }

        mutex_lock(&dp->addr_lists_lock);

        a = dsa_mac_addr_find(&dp->fdbs, addr, vid, db);
        if (a) {
                refcount_inc(&a->refcount);
                trace_dsa_fdb_add_bump(dp, addr, vid, &db, &a->refcount);
                goto out;
        }

        a = kzalloc_obj(*a);
        if (!a) {
                err = -ENOMEM;
                goto out;
        }

        err = ds->ops->port_fdb_add(ds, port, addr, vid, db);
        trace_dsa_fdb_add_hw(dp, addr, vid, &db, err);
        if (err) {
                kfree(a);
                goto out;
        }

        ether_addr_copy(a->addr, addr);
        a->vid = vid;
        a->db = db;
        refcount_set(&a->refcount, 1);
        list_add_tail(&a->list, &dp->fdbs);

out:
        mutex_unlock(&dp->addr_lists_lock);

        return err;
}

static int dsa_port_do_fdb_del(struct dsa_port *dp, const unsigned char *addr,
                               u16 vid, struct dsa_db db)
{
        struct dsa_switch *ds = dp->ds;
        struct dsa_mac_addr *a;
        int port = dp->index;
        int err = 0;

        /* No need to bother with refcounting for user ports */
        if (!(dsa_port_is_cpu(dp) || dsa_port_is_dsa(dp))) {
                err = ds->ops->port_fdb_del(ds, port, addr, vid, db);
                trace_dsa_fdb_del_hw(dp, addr, vid, &db, err);

                return err;
        }

        mutex_lock(&dp->addr_lists_lock);

        a = dsa_mac_addr_find(&dp->fdbs, addr, vid, db);
        if (!a) {
                trace_dsa_fdb_del_not_found(dp, addr, vid, &db);
                err = -ENOENT;
                goto out;
        }

        if (!refcount_dec_and_test(&a->refcount)) {
                trace_dsa_fdb_del_drop(dp, addr, vid, &db, &a->refcount);
                goto out;
        }

        err = ds->ops->port_fdb_del(ds, port, addr, vid, db);
        trace_dsa_fdb_del_hw(dp, addr, vid, &db, err);
        if (err) {
                refcount_set(&a->refcount, 1);
                goto out;
        }

        list_del(&a->list);
        kfree(a);

out:
        mutex_unlock(&dp->addr_lists_lock);

        return err;
}

static int dsa_switch_do_lag_fdb_add(struct dsa_switch *ds, struct dsa_lag *lag,
                                     const unsigned char *addr, u16 vid,
                                     struct dsa_db db)
{
        struct dsa_mac_addr *a;
        int err = 0;

        mutex_lock(&lag->fdb_lock);

        a = dsa_mac_addr_find(&lag->fdbs, addr, vid, db);
        if (a) {
                refcount_inc(&a->refcount);
                trace_dsa_lag_fdb_add_bump(lag->dev, addr, vid, &db,
                                           &a->refcount);
                goto out;
        }

        a = kzalloc_obj(*a);
        if (!a) {
                err = -ENOMEM;
                goto out;
        }

        err = ds->ops->lag_fdb_add(ds, *lag, addr, vid, db);
        trace_dsa_lag_fdb_add_hw(lag->dev, addr, vid, &db, err);
        if (err) {
                kfree(a);
                goto out;
        }

        ether_addr_copy(a->addr, addr);
        a->vid = vid;
        a->db = db;
        refcount_set(&a->refcount, 1);
        list_add_tail(&a->list, &lag->fdbs);

out:
        mutex_unlock(&lag->fdb_lock);

        return err;
}

static int dsa_switch_do_lag_fdb_del(struct dsa_switch *ds, struct dsa_lag *lag,
                                     const unsigned char *addr, u16 vid,
                                     struct dsa_db db)
{
        struct dsa_mac_addr *a;
        int err = 0;

        mutex_lock(&lag->fdb_lock);

        a = dsa_mac_addr_find(&lag->fdbs, addr, vid, db);
        if (!a) {
                trace_dsa_lag_fdb_del_not_found(lag->dev, addr, vid, &db);
                err = -ENOENT;
                goto out;
        }

        if (!refcount_dec_and_test(&a->refcount)) {
                trace_dsa_lag_fdb_del_drop(lag->dev, addr, vid, &db,
                                           &a->refcount);
                goto out;
        }

        err = ds->ops->lag_fdb_del(ds, *lag, addr, vid, db);
        trace_dsa_lag_fdb_del_hw(lag->dev, addr, vid, &db, err);
        if (err) {
                refcount_set(&a->refcount, 1);
                goto out;
        }

        list_del(&a->list);
        kfree(a);

out:
        mutex_unlock(&lag->fdb_lock);

        return err;
}

static int dsa_switch_host_fdb_add(struct dsa_switch *ds,
                                   struct dsa_notifier_fdb_info *info)
{
        struct dsa_port *dp;
        int err = 0;

        if (!ds->ops->port_fdb_add)
                return -EOPNOTSUPP;

        dsa_switch_for_each_port(dp, ds) {
                if (dsa_port_host_address_match(dp, info->dp)) {
                        if (dsa_port_is_cpu(dp) && info->dp->cpu_port_in_lag) {
                                err = dsa_switch_do_lag_fdb_add(ds, dp->lag,
                                                                info->addr,
                                                                info->vid,
                                                                info->db);
                        } else {
                                err = dsa_port_do_fdb_add(dp, info->addr,
                                                          info->vid, info->db);
                        }
                        if (err)
                                break;
                }
        }

        return err;
}

static int dsa_switch_host_fdb_del(struct dsa_switch *ds,
                                   struct dsa_notifier_fdb_info *info)
{
        struct dsa_port *dp;
        int err = 0;

        if (!ds->ops->port_fdb_del)
                return -EOPNOTSUPP;

        dsa_switch_for_each_port(dp, ds) {
                if (dsa_port_host_address_match(dp, info->dp)) {
                        if (dsa_port_is_cpu(dp) && info->dp->cpu_port_in_lag) {
                                err = dsa_switch_do_lag_fdb_del(ds, dp->lag,
                                                                info->addr,
                                                                info->vid,
                                                                info->db);
                        } else {
                                err = dsa_port_do_fdb_del(dp, info->addr,
                                                          info->vid, info->db);
                        }
                        if (err)
                                break;
                }
        }

        return err;
}

static int dsa_switch_fdb_add(struct dsa_switch *ds,
                              struct dsa_notifier_fdb_info *info)
{
        int port = dsa_towards_port(ds, info->dp->ds->index, info->dp->index);
        struct dsa_port *dp = dsa_to_port(ds, port);

        if (!ds->ops->port_fdb_add)
                return -EOPNOTSUPP;

        return dsa_port_do_fdb_add(dp, info->addr, info->vid, info->db);
}

static int dsa_switch_fdb_del(struct dsa_switch *ds,
                              struct dsa_notifier_fdb_info *info)
{
        int port = dsa_towards_port(ds, info->dp->ds->index, info->dp->index);
        struct dsa_port *dp = dsa_to_port(ds, port);

        if (!ds->ops->port_fdb_del)
                return -EOPNOTSUPP;

        return dsa_port_do_fdb_del(dp, info->addr, info->vid, info->db);
}

static int dsa_switch_lag_fdb_add(struct dsa_switch *ds,
                                  struct dsa_notifier_lag_fdb_info *info)
{
        struct dsa_port *dp;

        if (!ds->ops->lag_fdb_add)
                return -EOPNOTSUPP;

        /* Notify switch only if it has a port in this LAG */
        dsa_switch_for_each_port(dp, ds)
                if (dsa_port_offloads_lag(dp, info->lag))
                        return dsa_switch_do_lag_fdb_add(ds, info->lag,
                                                         info->addr, info->vid,
                                                         info->db);

        return 0;
}

static int dsa_switch_lag_fdb_del(struct dsa_switch *ds,
                                  struct dsa_notifier_lag_fdb_info *info)
{
        struct dsa_port *dp;

        if (!ds->ops->lag_fdb_del)
                return -EOPNOTSUPP;

        /* Notify switch only if it has a port in this LAG */
        dsa_switch_for_each_port(dp, ds)
                if (dsa_port_offloads_lag(dp, info->lag))
                        return dsa_switch_do_lag_fdb_del(ds, info->lag,
                                                         info->addr, info->vid,
                                                         info->db);

        return 0;
}

static int dsa_switch_lag_change(struct dsa_switch *ds,
                                 struct dsa_notifier_lag_info *info)
{
        if (info->dp->ds == ds && ds->ops->port_lag_change)
                return ds->ops->port_lag_change(ds, info->dp->index);

        if (info->dp->ds != ds && ds->ops->crosschip_lag_change)
                return ds->ops->crosschip_lag_change(ds, info->dp->ds->index,
                                                     info->dp->index);

        return 0;
}

static int dsa_switch_lag_join(struct dsa_switch *ds,
                               struct dsa_notifier_lag_info *info)
{
        if (info->dp->ds == ds && ds->ops->port_lag_join)
                return ds->ops->port_lag_join(ds, info->dp->index, info->lag,
                                              info->info, info->extack);

        if (info->dp->ds != ds && ds->ops->crosschip_lag_join)
                return ds->ops->crosschip_lag_join(ds, info->dp->ds->index,
                                                   info->dp->index, info->lag,
                                                   info->info, info->extack);

        return -EOPNOTSUPP;
}

static int dsa_switch_lag_leave(struct dsa_switch *ds,
                                struct dsa_notifier_lag_info *info)
{
        if (info->dp->ds == ds && ds->ops->port_lag_leave)
                return ds->ops->port_lag_leave(ds, info->dp->index, info->lag);

        if (info->dp->ds != ds && ds->ops->crosschip_lag_leave)
                return ds->ops->crosschip_lag_leave(ds, info->dp->ds->index,
                                                    info->dp->index, info->lag);

        return -EOPNOTSUPP;
}

static int dsa_switch_mdb_add(struct dsa_switch *ds,
                              struct dsa_notifier_mdb_info *info)
{
        int port = dsa_towards_port(ds, info->dp->ds->index, info->dp->index);
        struct dsa_port *dp = dsa_to_port(ds, port);

        if (!ds->ops->port_mdb_add)
                return -EOPNOTSUPP;

        return dsa_port_do_mdb_add(dp, info->mdb, info->db);
}

static int dsa_switch_mdb_del(struct dsa_switch *ds,
                              struct dsa_notifier_mdb_info *info)
{
        int port = dsa_towards_port(ds, info->dp->ds->index, info->dp->index);
        struct dsa_port *dp = dsa_to_port(ds, port);

        if (!ds->ops->port_mdb_del)
                return -EOPNOTSUPP;

        return dsa_port_do_mdb_del(dp, info->mdb, info->db);
}

static int dsa_switch_host_mdb_add(struct dsa_switch *ds,
                                   struct dsa_notifier_mdb_info *info)
{
        struct dsa_port *dp;
        int err = 0;

        if (!ds->ops->port_mdb_add)
                return -EOPNOTSUPP;

        dsa_switch_for_each_port(dp, ds) {
                if (dsa_port_host_address_match(dp, info->dp)) {
                        err = dsa_port_do_mdb_add(dp, info->mdb, info->db);
                        if (err)
                                break;
                }
        }

        return err;
}

static int dsa_switch_host_mdb_del(struct dsa_switch *ds,
                                   struct dsa_notifier_mdb_info *info)
{
        struct dsa_port *dp;
        int err = 0;

        if (!ds->ops->port_mdb_del)
                return -EOPNOTSUPP;

        dsa_switch_for_each_port(dp, ds) {
                if (dsa_port_host_address_match(dp, info->dp)) {
                        err = dsa_port_do_mdb_del(dp, info->mdb, info->db);
                        if (err)
                                break;
                }
        }

        return err;
}

/* Port VLANs match on the targeted port and on all DSA ports */
static bool dsa_port_vlan_match(struct dsa_port *dp,
                                struct dsa_notifier_vlan_info *info)
{
        return dsa_port_is_dsa(dp) || dp == info->dp;
}

/* Host VLANs match on the targeted port's CPU port, and on all DSA ports
 * (upstream and downstream) of that switch and its upstream switches.
 */
static bool dsa_port_host_vlan_match(struct dsa_port *dp,
                                     const struct dsa_port *targeted_dp)
{
        struct dsa_port *cpu_dp = targeted_dp->cpu_dp;

        if (dsa_switch_is_upstream_of(dp->ds, targeted_dp->ds))
                return dsa_port_is_dsa(dp) || dp == cpu_dp;

        return false;
}

struct dsa_vlan *dsa_vlan_find(struct list_head *vlan_list,
                               const struct switchdev_obj_port_vlan *vlan)
{
        struct dsa_vlan *v;

        list_for_each_entry(v, vlan_list, list)
                if (v->vid == vlan->vid)
                        return v;

        return NULL;
}

static int dsa_port_do_vlan_add(struct dsa_port *dp,
                                const struct switchdev_obj_port_vlan *vlan,
                                struct netlink_ext_ack *extack)
{
        struct dsa_switch *ds = dp->ds;
        int port = dp->index;
        struct dsa_vlan *v;
        int err = 0;

        /* No need to bother with refcounting for user ports. */
        if (!(dsa_port_is_cpu(dp) || dsa_port_is_dsa(dp))) {
                err = ds->ops->port_vlan_add(ds, port, vlan, extack);
                trace_dsa_vlan_add_hw(dp, vlan, err);

                return err;
        }

        /* No need to propagate on shared ports the existing VLANs that were
         * re-notified after just the flags have changed. This would cause a
         * refcount bump which we need to avoid, since it unbalances the
         * additions with the deletions.
         */
        if (vlan->changed)
                return 0;

        mutex_lock(&dp->vlans_lock);

        v = dsa_vlan_find(&dp->vlans, vlan);
        if (v) {
                refcount_inc(&v->refcount);
                trace_dsa_vlan_add_bump(dp, vlan, &v->refcount);
                goto out;
        }

        v = kzalloc_obj(*v);
        if (!v) {
                err = -ENOMEM;
                goto out;
        }

        err = ds->ops->port_vlan_add(ds, port, vlan, extack);
        trace_dsa_vlan_add_hw(dp, vlan, err);
        if (err) {
                kfree(v);
                goto out;
        }

        v->vid = vlan->vid;
        refcount_set(&v->refcount, 1);
        list_add_tail(&v->list, &dp->vlans);

out:
        mutex_unlock(&dp->vlans_lock);

        return err;
}

static int dsa_port_do_vlan_del(struct dsa_port *dp,
                                const struct switchdev_obj_port_vlan *vlan)
{
        struct dsa_switch *ds = dp->ds;
        int port = dp->index;
        struct dsa_vlan *v;
        int err = 0;

        /* No need to bother with refcounting for user ports */
        if (!(dsa_port_is_cpu(dp) || dsa_port_is_dsa(dp))) {
                err = ds->ops->port_vlan_del(ds, port, vlan);
                trace_dsa_vlan_del_hw(dp, vlan, err);

                return err;
        }

        mutex_lock(&dp->vlans_lock);

        v = dsa_vlan_find(&dp->vlans, vlan);
        if (!v) {
                trace_dsa_vlan_del_not_found(dp, vlan);
                err = -ENOENT;
                goto out;
        }

        if (!refcount_dec_and_test(&v->refcount)) {
                trace_dsa_vlan_del_drop(dp, vlan, &v->refcount);
                goto out;
        }

        err = ds->ops->port_vlan_del(ds, port, vlan);
        trace_dsa_vlan_del_hw(dp, vlan, err);
        if (err) {
                refcount_set(&v->refcount, 1);
                goto out;
        }

        list_del(&v->list);
        kfree(v);

out:
        mutex_unlock(&dp->vlans_lock);

        return err;
}

static int dsa_switch_vlan_add(struct dsa_switch *ds,
                               struct dsa_notifier_vlan_info *info)
{
        struct dsa_port *dp;
        int err;

        if (!ds->ops->port_vlan_add)
                return -EOPNOTSUPP;

        dsa_switch_for_each_port(dp, ds) {
                if (dsa_port_vlan_match(dp, info)) {
                        err = dsa_port_do_vlan_add(dp, info->vlan,
                                                   info->extack);
                        if (err)
                                return err;
                }
        }

        return 0;
}

static int dsa_switch_vlan_del(struct dsa_switch *ds,
                               struct dsa_notifier_vlan_info *info)
{
        struct dsa_port *dp;
        int err;

        if (!ds->ops->port_vlan_del)
                return -EOPNOTSUPP;

        dsa_switch_for_each_port(dp, ds) {
                if (dsa_port_vlan_match(dp, info)) {
                        err = dsa_port_do_vlan_del(dp, info->vlan);
                        if (err)
                                return err;
                }
        }

        return 0;
}

static int dsa_switch_host_vlan_add(struct dsa_switch *ds,
                                    struct dsa_notifier_vlan_info *info)
{
        struct dsa_port *dp;
        int err;

        if (!ds->ops->port_vlan_add)
                return -EOPNOTSUPP;

        dsa_switch_for_each_port(dp, ds) {
                if (dsa_port_host_vlan_match(dp, info->dp)) {
                        err = dsa_port_do_vlan_add(dp, info->vlan,
                                                   info->extack);
                        if (err)
                                return err;
                }
        }

        return 0;
}

static int dsa_switch_host_vlan_del(struct dsa_switch *ds,
                                    struct dsa_notifier_vlan_info *info)
{
        struct dsa_port *dp;
        int err;

        if (!ds->ops->port_vlan_del)
                return -EOPNOTSUPP;

        dsa_switch_for_each_port(dp, ds) {
                if (dsa_port_host_vlan_match(dp, info->dp)) {
                        err = dsa_port_do_vlan_del(dp, info->vlan);
                        if (err)
                                return err;
                }
        }

        return 0;
}

static int dsa_switch_change_tag_proto(struct dsa_switch *ds,
                                       struct dsa_notifier_tag_proto_info *info)
{
        const struct dsa_device_ops *tag_ops = info->tag_ops;
        struct dsa_port *dp, *cpu_dp;
        int err;

        if (!ds->ops->change_tag_protocol)
                return -EOPNOTSUPP;

        ASSERT_RTNL();

        err = ds->ops->change_tag_protocol(ds, tag_ops->proto);
        if (err)
                return err;

        dsa_switch_for_each_cpu_port(cpu_dp, ds)
                dsa_port_set_tag_protocol(cpu_dp, tag_ops);

        /* Now that changing the tag protocol can no longer fail, let's update
         * the remaining bits which are "duplicated for faster access", and the
         * bits that depend on the tagger, such as the MTU.
         */
        dsa_switch_for_each_user_port(dp, ds) {
                struct net_device *user = dp->user;

                dsa_user_setup_tagger(user);

                /* rtnl_mutex is held in dsa_tree_change_tag_proto */
                dsa_user_change_mtu(user, user->mtu);
        }

        return 0;
}

/* We use the same cross-chip notifiers to inform both the tagger side, as well
 * as the switch side, of connection and disconnection events.
 * Since ds->tagger_data is owned by the tagger, it isn't a hard error if the
 * switch side doesn't support connecting to this tagger, and therefore, the
 * fact that we don't disconnect the tagger side doesn't constitute a memory
 * leak: the tagger will still operate with persistent per-switch memory, just
 * with the switch side unconnected to it. What does constitute a hard error is
 * when the switch side supports connecting but fails.
 */
static int
dsa_switch_connect_tag_proto(struct dsa_switch *ds,
                             struct dsa_notifier_tag_proto_info *info)
{
        const struct dsa_device_ops *tag_ops = info->tag_ops;
        int err;

        /* Notify the new tagger about the connection to this switch */
        if (tag_ops->connect) {
                err = tag_ops->connect(ds);
                if (err)
                        return err;
        }

        if (!ds->ops->connect_tag_protocol)
                return -EOPNOTSUPP;

        /* Notify the switch about the connection to the new tagger */
        err = ds->ops->connect_tag_protocol(ds, tag_ops->proto);
        if (err) {
                /* Revert the new tagger's connection to this tree */
                if (tag_ops->disconnect)
                        tag_ops->disconnect(ds);
                return err;
        }

        return 0;
}

static int
dsa_switch_disconnect_tag_proto(struct dsa_switch *ds,
                                struct dsa_notifier_tag_proto_info *info)
{
        const struct dsa_device_ops *tag_ops = info->tag_ops;

        /* Notify the tagger about the disconnection from this switch */
        if (tag_ops->disconnect && ds->tagger_data)
                tag_ops->disconnect(ds);

        /* No need to notify the switch, since it shouldn't have any
         * resources to tear down
         */
        return 0;
}

static int
dsa_switch_conduit_state_change(struct dsa_switch *ds,
                                struct dsa_notifier_conduit_state_info *info)
{
        if (!ds->ops->conduit_state_change)
                return 0;

        ds->ops->conduit_state_change(ds, info->conduit, info->operational);

        return 0;
}

static int dsa_switch_event(struct notifier_block *nb,
                            unsigned long event, void *info)
{
        struct dsa_switch *ds = container_of(nb, struct dsa_switch, nb);
        int err;

        switch (event) {
        case DSA_NOTIFIER_AGEING_TIME:
                err = dsa_switch_ageing_time(ds, info);
                break;
        case DSA_NOTIFIER_BRIDGE_JOIN:
                err = dsa_switch_bridge_join(ds, info);
                break;
        case DSA_NOTIFIER_BRIDGE_LEAVE:
                err = dsa_switch_bridge_leave(ds, info);
                break;
        case DSA_NOTIFIER_FDB_ADD:
                err = dsa_switch_fdb_add(ds, info);
                break;
        case DSA_NOTIFIER_FDB_DEL:
                err = dsa_switch_fdb_del(ds, info);
                break;
        case DSA_NOTIFIER_HOST_FDB_ADD:
                err = dsa_switch_host_fdb_add(ds, info);
                break;
        case DSA_NOTIFIER_HOST_FDB_DEL:
                err = dsa_switch_host_fdb_del(ds, info);
                break;
        case DSA_NOTIFIER_LAG_FDB_ADD:
                err = dsa_switch_lag_fdb_add(ds, info);
                break;
        case DSA_NOTIFIER_LAG_FDB_DEL:
                err = dsa_switch_lag_fdb_del(ds, info);
                break;
        case DSA_NOTIFIER_LAG_CHANGE:
                err = dsa_switch_lag_change(ds, info);
                break;
        case DSA_NOTIFIER_LAG_JOIN:
                err = dsa_switch_lag_join(ds, info);
                break;
        case DSA_NOTIFIER_LAG_LEAVE:
                err = dsa_switch_lag_leave(ds, info);
                break;
        case DSA_NOTIFIER_MDB_ADD:
                err = dsa_switch_mdb_add(ds, info);
                break;
        case DSA_NOTIFIER_MDB_DEL:
                err = dsa_switch_mdb_del(ds, info);
                break;
        case DSA_NOTIFIER_HOST_MDB_ADD:
                err = dsa_switch_host_mdb_add(ds, info);
                break;
        case DSA_NOTIFIER_HOST_MDB_DEL:
                err = dsa_switch_host_mdb_del(ds, info);
                break;
        case DSA_NOTIFIER_VLAN_ADD:
                err = dsa_switch_vlan_add(ds, info);
                break;
        case DSA_NOTIFIER_VLAN_DEL:
                err = dsa_switch_vlan_del(ds, info);
                break;
        case DSA_NOTIFIER_HOST_VLAN_ADD:
                err = dsa_switch_host_vlan_add(ds, info);
                break;
        case DSA_NOTIFIER_HOST_VLAN_DEL:
                err = dsa_switch_host_vlan_del(ds, info);
                break;
        case DSA_NOTIFIER_MTU:
                err = dsa_switch_mtu(ds, info);
                break;
        case DSA_NOTIFIER_TAG_PROTO:
                err = dsa_switch_change_tag_proto(ds, info);
                break;
        case DSA_NOTIFIER_TAG_PROTO_CONNECT:
                err = dsa_switch_connect_tag_proto(ds, info);
                break;
        case DSA_NOTIFIER_TAG_PROTO_DISCONNECT:
                err = dsa_switch_disconnect_tag_proto(ds, info);
                break;
        case DSA_NOTIFIER_TAG_8021Q_VLAN_ADD:
                err = dsa_switch_tag_8021q_vlan_add(ds, info);
                break;
        case DSA_NOTIFIER_TAG_8021Q_VLAN_DEL:
                err = dsa_switch_tag_8021q_vlan_del(ds, info);
                break;
        case DSA_NOTIFIER_CONDUIT_STATE_CHANGE:
                err = dsa_switch_conduit_state_change(ds, info);
                break;
        default:
                err = -EOPNOTSUPP;
                break;
        }

        if (err)
                dev_dbg(ds->dev, "breaking chain for DSA event %lu (%d)\n",
                        event, err);

        return notifier_from_errno(err);
}

/**
 * dsa_tree_notify - Execute code for all switches in a DSA switch tree.
 * @dst: collection of struct dsa_switch devices to notify.
 * @e: event, must be of type DSA_NOTIFIER_*
 * @v: event-specific value.
 *
 * Given a struct dsa_switch_tree, this can be used to run a function once for
 * each member DSA switch. The other alternative of traversing the tree is only
 * through its ports list, which does not uniquely list the switches.
 */
int dsa_tree_notify(struct dsa_switch_tree *dst, unsigned long e, void *v)
{
        struct raw_notifier_head *nh = &dst->nh;
        int err;

        err = raw_notifier_call_chain(nh, e, v);

        return notifier_to_errno(err);
}

/**
 * dsa_broadcast - Notify all DSA trees in the system.
 * @e: event, must be of type DSA_NOTIFIER_*
 * @v: event-specific value.
 *
 * Can be used to notify the switching fabric of events such as cross-chip
 * bridging between disjoint trees (such as islands of tagger-compatible
 * switches bridged by an incompatible middle switch).
 *
 * WARNING: this function is not reliable during probe time, because probing
 * between trees is asynchronous and not all DSA trees might have probed.
 */
int dsa_broadcast(unsigned long e, void *v)
{
        struct dsa_switch_tree *dst;
        int err = 0;

        list_for_each_entry(dst, &dsa_tree_list, list) {
                err = dsa_tree_notify(dst, e, v);
                if (err)
                        break;
        }

        return err;
}

int dsa_switch_register_notifier(struct dsa_switch *ds)
{
        ds->nb.notifier_call = dsa_switch_event;

        return raw_notifier_chain_register(&ds->dst->nh, &ds->nb);
}

void dsa_switch_unregister_notifier(struct dsa_switch *ds)
{
        int err;

        err = raw_notifier_chain_unregister(&ds->dst->nh, &ds->nb);
        if (err)
                dev_err(ds->dev, "failed to unregister notifier (%d)\n", err);
}