v4.19.13 snapshot.
diff --git a/net/dsa/switch.c b/net/dsa/switch.c
new file mode 100644
index 0000000..142b294
--- /dev/null
+++ b/net/dsa/switch.c
@@ -0,0 +1,302 @@
+/*
+ * Handling of a single switch chip, part of a switch fabric
+ *
+ * Copyright (c) 2017 Savoir-faire Linux Inc.
+ *	Vivien Didelot <vivien.didelot@savoirfairelinux.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/netdevice.h>
+#include <linux/notifier.h>
+#include <net/switchdev.h>
+
+#include "dsa_priv.h"
+
+static unsigned int dsa_switch_fastest_ageing_time(struct dsa_switch *ds,
+						   unsigned int ageing_time)
+{
+	int i;
+
+	for (i = 0; i < ds->num_ports; ++i) {
+		struct dsa_port *dp = &ds->ports[i];
+
+		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;
+	struct switchdev_trans *trans = info->trans;
+
+	if (switchdev_trans_ph_prepare(trans)) {
+		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;
+		return 0;
+	}
+
+	/* 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 int dsa_switch_bridge_join(struct dsa_switch *ds,
+				  struct dsa_notifier_bridge_info *info)
+{
+	if (ds->index == info->sw_index && ds->ops->port_bridge_join)
+		return ds->ops->port_bridge_join(ds, info->port, info->br);
+
+	if (ds->index != info->sw_index && ds->ops->crosschip_bridge_join)
+		return ds->ops->crosschip_bridge_join(ds, info->sw_index,
+						      info->port, info->br);
+
+	return 0;
+}
+
+static int dsa_switch_bridge_leave(struct dsa_switch *ds,
+				   struct dsa_notifier_bridge_info *info)
+{
+	if (ds->index == info->sw_index && ds->ops->port_bridge_leave)
+		ds->ops->port_bridge_leave(ds, info->port, info->br);
+
+	if (ds->index != info->sw_index && ds->ops->crosschip_bridge_leave)
+		ds->ops->crosschip_bridge_leave(ds, info->sw_index, info->port,
+						info->br);
+
+	return 0;
+}
+
+static int dsa_switch_fdb_add(struct dsa_switch *ds,
+			      struct dsa_notifier_fdb_info *info)
+{
+	int port = dsa_towards_port(ds, info->sw_index, info->port);
+
+	if (!ds->ops->port_fdb_add)
+		return -EOPNOTSUPP;
+
+	return ds->ops->port_fdb_add(ds, port, info->addr, info->vid);
+}
+
+static int dsa_switch_fdb_del(struct dsa_switch *ds,
+			      struct dsa_notifier_fdb_info *info)
+{
+	int port = dsa_towards_port(ds, info->sw_index, info->port);
+
+	if (!ds->ops->port_fdb_del)
+		return -EOPNOTSUPP;
+
+	return ds->ops->port_fdb_del(ds, port, info->addr, info->vid);
+}
+
+static int
+dsa_switch_mdb_prepare_bitmap(struct dsa_switch *ds,
+			      const struct switchdev_obj_port_mdb *mdb,
+			      const unsigned long *bitmap)
+{
+	int port, err;
+
+	if (!ds->ops->port_mdb_prepare || !ds->ops->port_mdb_add)
+		return -EOPNOTSUPP;
+
+	for_each_set_bit(port, bitmap, ds->num_ports) {
+		err = ds->ops->port_mdb_prepare(ds, port, mdb);
+		if (err)
+			return err;
+	}
+
+	return 0;
+}
+
+static void dsa_switch_mdb_add_bitmap(struct dsa_switch *ds,
+				      const struct switchdev_obj_port_mdb *mdb,
+				      const unsigned long *bitmap)
+{
+	int port;
+
+	for_each_set_bit(port, bitmap, ds->num_ports)
+		ds->ops->port_mdb_add(ds, port, mdb);
+}
+
+static int dsa_switch_mdb_add(struct dsa_switch *ds,
+			      struct dsa_notifier_mdb_info *info)
+{
+	const struct switchdev_obj_port_mdb *mdb = info->mdb;
+	struct switchdev_trans *trans = info->trans;
+	int port;
+
+	/* Build a mask of Multicast group members */
+	bitmap_zero(ds->bitmap, ds->num_ports);
+	if (ds->index == info->sw_index)
+		set_bit(info->port, ds->bitmap);
+	for (port = 0; port < ds->num_ports; port++)
+		if (dsa_is_dsa_port(ds, port))
+			set_bit(port, ds->bitmap);
+
+	if (switchdev_trans_ph_prepare(trans))
+		return dsa_switch_mdb_prepare_bitmap(ds, mdb, ds->bitmap);
+
+	dsa_switch_mdb_add_bitmap(ds, mdb, ds->bitmap);
+
+	return 0;
+}
+
+static int dsa_switch_mdb_del(struct dsa_switch *ds,
+			      struct dsa_notifier_mdb_info *info)
+{
+	const struct switchdev_obj_port_mdb *mdb = info->mdb;
+
+	if (!ds->ops->port_mdb_del)
+		return -EOPNOTSUPP;
+
+	if (ds->index == info->sw_index)
+		return ds->ops->port_mdb_del(ds, info->port, mdb);
+
+	return 0;
+}
+
+static int
+dsa_switch_vlan_prepare_bitmap(struct dsa_switch *ds,
+			       const struct switchdev_obj_port_vlan *vlan,
+			       const unsigned long *bitmap)
+{
+	int port, err;
+
+	if (!ds->ops->port_vlan_prepare || !ds->ops->port_vlan_add)
+		return -EOPNOTSUPP;
+
+	for_each_set_bit(port, bitmap, ds->num_ports) {
+		err = ds->ops->port_vlan_prepare(ds, port, vlan);
+		if (err)
+			return err;
+	}
+
+	return 0;
+}
+
+static void
+dsa_switch_vlan_add_bitmap(struct dsa_switch *ds,
+			   const struct switchdev_obj_port_vlan *vlan,
+			   const unsigned long *bitmap)
+{
+	int port;
+
+	for_each_set_bit(port, bitmap, ds->num_ports)
+		ds->ops->port_vlan_add(ds, port, vlan);
+}
+
+static int dsa_switch_vlan_add(struct dsa_switch *ds,
+			       struct dsa_notifier_vlan_info *info)
+{
+	const struct switchdev_obj_port_vlan *vlan = info->vlan;
+	struct switchdev_trans *trans = info->trans;
+	int port;
+
+	/* Build a mask of VLAN members */
+	bitmap_zero(ds->bitmap, ds->num_ports);
+	if (ds->index == info->sw_index)
+		set_bit(info->port, ds->bitmap);
+	for (port = 0; port < ds->num_ports; port++)
+		if (dsa_is_cpu_port(ds, port) || dsa_is_dsa_port(ds, port))
+			set_bit(port, ds->bitmap);
+
+	if (switchdev_trans_ph_prepare(trans))
+		return dsa_switch_vlan_prepare_bitmap(ds, vlan, ds->bitmap);
+
+	dsa_switch_vlan_add_bitmap(ds, vlan, ds->bitmap);
+
+	return 0;
+}
+
+static int dsa_switch_vlan_del(struct dsa_switch *ds,
+			       struct dsa_notifier_vlan_info *info)
+{
+	const struct switchdev_obj_port_vlan *vlan = info->vlan;
+
+	if (!ds->ops->port_vlan_del)
+		return -EOPNOTSUPP;
+
+	if (ds->index == info->sw_index)
+		return ds->ops->port_vlan_del(ds, info->port, vlan);
+
+	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_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_VLAN_ADD:
+		err = dsa_switch_vlan_add(ds, info);
+		break;
+	case DSA_NOTIFIER_VLAN_DEL:
+		err = dsa_switch_vlan_del(ds, info);
+		break;
+	default:
+		err = -EOPNOTSUPP;
+		break;
+	}
+
+	/* Non-switchdev operations cannot be rolled back. If a DSA driver
+	 * returns an error during the chained call, switch chips may be in an
+	 * inconsistent state.
+	 */
+	if (err)
+		dev_dbg(ds->dev, "breaking chain for DSA event %lu (%d)\n",
+			event, err);
+
+	return notifier_from_errno(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);
+}