Update Linux to v5.4.2

Change-Id: Idf6911045d9d382da2cfe01b1edff026404ac8fd
diff --git a/net/dsa/switch.c b/net/dsa/switch.c
index 142b294..6a96075 100644
--- a/net/dsa/switch.c
+++ b/net/dsa/switch.c
@@ -1,17 +1,15 @@
+// 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>
- *
- * 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/if_bridge.h>
 #include <linux/netdevice.h>
 #include <linux/notifier.h>
+#include <linux/if_vlan.h>
 #include <net/switchdev.h>
 
 #include "dsa_priv.h"
@@ -70,6 +68,9 @@
 static int dsa_switch_bridge_leave(struct dsa_switch *ds,
 				   struct dsa_notifier_bridge_info *info)
 {
+	bool unset_vlan_filtering = br_vlan_enabled(info->br);
+	int err, i;
+
 	if (ds->index == info->sw_index && ds->ops->port_bridge_leave)
 		ds->ops->port_bridge_leave(ds, info->port, info->br);
 
@@ -77,6 +78,31 @@
 		ds->ops->crosschip_bridge_leave(ds, info->sw_index, info->port,
 						info->br);
 
+	/* If the bridge was vlan_filtering, the bridge core doesn't trigger an
+	 * event for changing vlan_filtering setting upon slave ports leaving
+	 * it. That is a good thing, because that lets us handle it and also
+	 * handle the case where the switch's vlan_filtering setting is global
+	 * (not per port). When that happens, the correct moment to trigger the
+	 * vlan_filtering callback is only when the last port left this bridge.
+	 */
+	if (unset_vlan_filtering && ds->vlan_filtering_is_global) {
+		for (i = 0; i < ds->num_ports; i++) {
+			if (i == info->port)
+				continue;
+			if (dsa_to_port(ds, i)->bridge_dev == info->br) {
+				unset_vlan_filtering = false;
+				break;
+			}
+		}
+	}
+	if (unset_vlan_filtering) {
+		struct switchdev_trans trans = {0};
+
+		err = dsa_port_vlan_filtering(&ds->ports[info->port],
+					      false, &trans);
+		if (err && err != EOPNOTSUPP)
+			return err;
+	}
 	return 0;
 }
 
@@ -102,54 +128,51 @@
 	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)
+static bool dsa_switch_mdb_match(struct dsa_switch *ds, int port,
+				 struct dsa_notifier_mdb_info *info)
+{
+	if (ds->index == info->sw_index && port == info->port)
+		return true;
+
+	if (dsa_is_dsa_port(ds, port))
+		return true;
+
+	return false;
+}
+
+static int dsa_switch_mdb_prepare(struct dsa_switch *ds,
+				  struct dsa_notifier_mdb_info *info)
 {
 	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;
+	for (port = 0; port < ds->num_ports; port++) {
+		if (dsa_switch_mdb_match(ds, port, info)) {
+			err = ds->ops->port_mdb_prepare(ds, port, info->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);
+	if (switchdev_trans_ph_prepare(info->trans))
+		return dsa_switch_mdb_prepare(ds, info);
+
+	if (!ds->ops->port_mdb_add)
+		return 0;
+
 	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);
+		if (dsa_switch_mdb_match(ds, port, info))
+			ds->ops->port_mdb_add(ds, port, info->mdb);
 
 	return 0;
 }
@@ -157,66 +180,101 @@
 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 ds->ops->port_mdb_del(ds, info->port, info->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)
+static int dsa_port_vlan_device_check(struct net_device *vlan_dev,
+				      int vlan_dev_vid,
+				      void *arg)
+{
+	struct switchdev_obj_port_vlan *vlan = arg;
+	u16 vid;
+
+	for (vid = vlan->vid_begin; vid <= vlan->vid_end; ++vid) {
+		if (vid == vlan_dev_vid)
+			return -EBUSY;
+	}
+
+	return 0;
+}
+
+static int dsa_port_vlan_check(struct dsa_switch *ds, int port,
+			       const struct switchdev_obj_port_vlan *vlan)
+{
+	const struct dsa_port *dp = dsa_to_port(ds, port);
+	int err = 0;
+
+	/* Device is not bridged, let it proceed with the VLAN device
+	 * creation.
+	 */
+	if (!dp->bridge_dev)
+		return err;
+
+	/* dsa_slave_vlan_rx_{add,kill}_vid() cannot use the prepare phase and
+	 * already checks whether there is an overlapping bridge VLAN entry
+	 * with the same VID, so here we only need to check that if we are
+	 * adding a bridge VLAN entry there is not an overlapping VLAN device
+	 * claiming that VID.
+	 */
+	return vlan_for_each(dp->slave, dsa_port_vlan_device_check,
+			     (void *)vlan);
+}
+
+static bool dsa_switch_vlan_match(struct dsa_switch *ds, int port,
+				  struct dsa_notifier_vlan_info *info)
+{
+	if (ds->index == info->sw_index && port == info->port)
+		return true;
+
+	if (dsa_is_dsa_port(ds, port))
+		return true;
+
+	return false;
+}
+
+static int dsa_switch_vlan_prepare(struct dsa_switch *ds,
+				   struct dsa_notifier_vlan_info *info)
 {
 	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;
+	for (port = 0; port < ds->num_ports; port++) {
+		if (dsa_switch_vlan_match(ds, port, info)) {
+			err = dsa_port_vlan_check(ds, port, info->vlan);
+			if (err)
+				return err;
+
+			err = ds->ops->port_vlan_prepare(ds, port, info->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);
+	if (switchdev_trans_ph_prepare(info->trans))
+		return dsa_switch_vlan_prepare(ds, info);
+
+	if (!ds->ops->port_vlan_add)
+		return 0;
+
 	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);
+		if (dsa_switch_vlan_match(ds, port, info))
+			ds->ops->port_vlan_add(ds, port, info->vlan);
 
 	return 0;
 }
@@ -224,14 +282,15 @@
 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 ds->ops->port_vlan_del(ds, info->port, info->vlan);
 
+	/* Do not deprogram the DSA links as they may be used as conduit
+	 * for other VLAN members in the fabric.
+	 */
 	return 0;
 }