Adding upstream version 6.6.15.upstream/6.6.15

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 1134 insertions, 0 deletions

diff --git a/net/dsa/switch.c b/net/dsa/switch.c
new file mode 100644
index 0000000000..1a42f93173
--- /dev/null
+++ b/net/dsa/switch.c
@@ -0,0 +1,1134 @@
+// 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 "slave.h"
+#include "switch.h"
+#include "tag_8021q.h"
+#include "trace.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(sizeof(*a), GFP_KERNEL);
+	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(sizeof(*a), GFP_KERNEL);
+	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(sizeof(*a), GFP_KERNEL);
+	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(sizeof(*v), GFP_KERNEL);
+	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 *slave = dp->slave;
+
+		dsa_slave_setup_tagger(slave);
+
+		/* rtnl_mutex is held in dsa_tree_change_tag_proto */
+		dsa_slave_change_mtu(slave, slave->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_master_state_change(struct dsa_switch *ds,
+			       struct dsa_notifier_master_state_info *info)
+{
+	if (!ds->ops->master_state_change)
+		return 0;
+
+	ds->ops->master_state_change(ds, info->master, 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_MASTER_STATE_CHANGE:
+		err = dsa_switch_master_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);
+}