From 066dfc4290406b1b0b014ae3267d4266a344efd1 Mon Sep 17 00:00:00 2001
From: Vladimir Oltean <vladimir.oltean@nxp.com>
Date: Thu, 31 Mar 2022 16:28:54 +0300
Subject: Revert "net: dsa: stop updating master MTU from master.c"

This reverts commit a1ff94c2973c43bc1e2677ac63ebb15b1d1ff846.

Switch drivers that don't implement ->port_change_mtu() will cause the
DSA master to remain with an MTU of 1500, since we've deleted the other
code path. In turn, this causes a regression for those systems, where
MTU-sized traffic can no longer be terminated.

Revert the change taking into account the fact that rtnl_lock() is now
taken top-level from the callers of dsa_master_setup() and
dsa_master_teardown(). Also add a comment in order for it to be
absolutely clear why it is still needed.

Fixes: a1ff94c2973c ("net: dsa: stop updating master MTU from master.c")
Reported-by: Luiz Angelo Daros de Luca <luizluca@gmail.com>
Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Tested-by: Luiz Angelo Daros de Luca <luizluca@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
---
 net/dsa/master.c | 25 ++++++++++++++++++++++++-
 1 file changed, 24 insertions(+), 1 deletion(-)

(limited to 'net/dsa')

diff --git a/net/dsa/master.c b/net/dsa/master.c
index 991c2930d631..2851e44c4cf0 100644
--- a/net/dsa/master.c
+++ b/net/dsa/master.c
@@ -335,11 +335,24 @@ static const struct attribute_group dsa_group = {
 	.attrs	= dsa_slave_attrs,
 };
 
+static void dsa_master_reset_mtu(struct net_device *dev)
+{
+	int err;
+
+	err = dev_set_mtu(dev, ETH_DATA_LEN);
+	if (err)
+		netdev_dbg(dev,
+			   "Unable to reset MTU to exclude DSA overheads\n");
+}
+
 int dsa_master_setup(struct net_device *dev, struct dsa_port *cpu_dp)
 {
+	const struct dsa_device_ops *tag_ops = cpu_dp->tag_ops;
 	struct dsa_switch *ds = cpu_dp->ds;
 	struct device_link *consumer_link;
-	int ret;
+	int mtu, ret;
+
+	mtu = ETH_DATA_LEN + dsa_tag_protocol_overhead(tag_ops);
 
 	/* The DSA master must use SET_NETDEV_DEV for this to work. */
 	consumer_link = device_link_add(ds->dev, dev->dev.parent,
@@ -349,6 +362,15 @@ int dsa_master_setup(struct net_device *dev, struct dsa_port *cpu_dp)
 			   "Failed to create a device link to DSA switch %s\n",
 			   dev_name(ds->dev));
 
+	/* The switch driver may not implement ->port_change_mtu(), case in
+	 * which dsa_slave_change_mtu() will not update the master MTU either,
+	 * so we need to do that here.
+	 */
+	ret = dev_set_mtu(dev, mtu);
+	if (ret)
+		netdev_warn(dev, "error %d setting MTU to %d to include DSA overhead\n",
+			    ret, mtu);
+
 	/* If we use a tagging format that doesn't have an ethertype
 	 * field, make sure that all packets from this point on get
 	 * sent to the tag format's receive function.
@@ -384,6 +406,7 @@ void dsa_master_teardown(struct net_device *dev)
 	sysfs_remove_group(&dev->dev.kobj, &dsa_group);
 	dsa_netdev_ops_set(dev, NULL);
 	dsa_master_ethtool_teardown(dev);
+	dsa_master_reset_mtu(dev);
 	dsa_master_set_promiscuity(dev, -1);
 
 	dev->dsa_ptr = NULL;
-- 
cgit v1.2.3


From 762c2998c9625f642f0d23da7d3f7e4f90665fdf Mon Sep 17 00:00:00 2001
From: Vladimir Oltean <vladimir.oltean@nxp.com>
Date: Tue, 12 Apr 2022 12:44:26 +0300
Subject: Revert "net: dsa: setup master before ports"

This reverts commit 11fd667dac315ea3f2469961f6d2869271a46cae.

dsa_slave_change_mtu() updates the MTU of the DSA master and of the
associated CPU port, but only if it detects a change to the master MTU.

The blamed commit in the Fixes: tag below addressed a regression where
dsa_slave_change_mtu() would return early and not do anything due to
ds->ops->port_change_mtu() not being implemented.

However, that commit also had the effect that the master MTU got set up
to the correct value by dsa_master_setup(), but the associated CPU port's
MTU did not get updated. This causes breakage for drivers that rely on
the ->port_change_mtu() DSA call to account for the tagging overhead on
the CPU port, and don't set up the initial MTU during the setup phase.

Things actually worked before because they were in a fragile equilibrium
where dsa_slave_change_mtu() was called before dsa_master_setup() was.
So dsa_slave_change_mtu() could actually detect a change and update the
CPU port MTU too.

Restore the code to the way things used to work by reverting the reorder
of dsa_tree_setup_master() and dsa_tree_setup_ports(). That change did
not have a concrete motivation going for it anyway, it just looked
better.

Fixes: 066dfc429040 ("Revert "net: dsa: stop updating master MTU from master.c"")
Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
---
 net/dsa/dsa2.c | 23 ++++++++++-------------
 1 file changed, 10 insertions(+), 13 deletions(-)

(limited to 'net/dsa')

diff --git a/net/dsa/dsa2.c b/net/dsa/dsa2.c
index ca6af86964bc..cf933225df32 100644
--- a/net/dsa/dsa2.c
+++ b/net/dsa/dsa2.c
@@ -562,7 +562,6 @@ static void dsa_port_teardown(struct dsa_port *dp)
 {
 	struct devlink_port *dlp = &dp->devlink_port;
 	struct dsa_switch *ds = dp->ds;
-	struct net_device *slave;
 
 	if (!dp->setup)
 		return;
@@ -584,11 +583,9 @@ static void dsa_port_teardown(struct dsa_port *dp)
 		dsa_port_link_unregister_of(dp);
 		break;
 	case DSA_PORT_TYPE_USER:
-		slave = dp->slave;
-
-		if (slave) {
+		if (dp->slave) {
+			dsa_slave_destroy(dp->slave);
 			dp->slave = NULL;
-			dsa_slave_destroy(slave);
 		}
 		break;
 	}
@@ -1147,17 +1144,17 @@ static int dsa_tree_setup(struct dsa_switch_tree *dst)
 	if (err)
 		goto teardown_cpu_ports;
 
-	err = dsa_tree_setup_master(dst);
+	err = dsa_tree_setup_ports(dst);
 	if (err)
 		goto teardown_switches;
 
-	err = dsa_tree_setup_ports(dst);
+	err = dsa_tree_setup_master(dst);
 	if (err)
-		goto teardown_master;
+		goto teardown_ports;
 
 	err = dsa_tree_setup_lags(dst);
 	if (err)
-		goto teardown_ports;
+		goto teardown_master;
 
 	dst->setup = true;
 
@@ -1165,10 +1162,10 @@ static int dsa_tree_setup(struct dsa_switch_tree *dst)
 
 	return 0;
 
-teardown_ports:
-	dsa_tree_teardown_ports(dst);
 teardown_master:
 	dsa_tree_teardown_master(dst);
+teardown_ports:
+	dsa_tree_teardown_ports(dst);
 teardown_switches:
 	dsa_tree_teardown_switches(dst);
 teardown_cpu_ports:
@@ -1186,10 +1183,10 @@ static void dsa_tree_teardown(struct dsa_switch_tree *dst)
 
 	dsa_tree_teardown_lags(dst);
 
-	dsa_tree_teardown_ports(dst);
-
 	dsa_tree_teardown_master(dst);
 
+	dsa_tree_teardown_ports(dst);
+
 	dsa_tree_teardown_switches(dst);
 
 	dsa_tree_teardown_cpu_ports(dst);
-- 
cgit v1.2.3


From 0763120b090418a5257402754e22a34227ae5f12 Mon Sep 17 00:00:00 2001
From: Kurt Kanzenbach <kurt@linutronix.de>
Date: Fri, 15 Apr 2022 12:33:20 +0200
Subject: net: dsa: hellcreek: Calculate checksums in tagger

In case the checksum calculation is offloaded to the DSA master network
interface, it will include the switch trailing tag. As soon as the switch strips
that tag on egress, the calculated checksum is wrong.

Therefore, add the checksum calculation to the tagger (if required) before
adding the switch tag. This way, the hellcreek code works with all DSA master
interfaces regardless of their declared feature set.

Fixes: 01ef09caad66 ("net: dsa: Add tag handling for Hirschmann Hellcreek switches")
Signed-off-by: Kurt Kanzenbach <kurt@linutronix.de>
Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Link: https://lore.kernel.org/r/20220415103320.90657-1-kurt@linutronix.de
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
---
 net/dsa/tag_hellcreek.c | 8 ++++++++
 1 file changed, 8 insertions(+)

(limited to 'net/dsa')

diff --git a/net/dsa/tag_hellcreek.c b/net/dsa/tag_hellcreek.c
index f64b805303cd..eb204ad36eee 100644
--- a/net/dsa/tag_hellcreek.c
+++ b/net/dsa/tag_hellcreek.c
@@ -21,6 +21,14 @@ static struct sk_buff *hellcreek_xmit(struct sk_buff *skb,
 	struct dsa_port *dp = dsa_slave_to_port(dev);
 	u8 *tag;
 
+	/* Calculate checksums (if required) before adding the trailer tag to
+	 * avoid including it in calculations. That would lead to wrong
+	 * checksums after the switch strips the tag.
+	 */
+	if (skb->ip_summed == CHECKSUM_PARTIAL &&
+	    skb_checksum_help(skb))
+		return NULL;
+
 	/* Tag encoding */
 	tag  = skb_put(skb, HELLCREEK_TAG_LEN);
 	*tag = BIT(dp->index);
-- 
cgit v1.2.3


From fc06b2867f4cea543505acfb194c2be4ebf0c7d3 Mon Sep 17 00:00:00 2001
From: Miaoqian Lin <linmq006@gmail.com>
Date: Wed, 20 Apr 2022 19:04:08 +0800
Subject: net: dsa: Add missing of_node_put() in dsa_port_link_register_of

The device_node pointer is returned by of_parse_phandle()  with refcount
incremented. We should use of_node_put() on it when done.
of_node_put() will check for NULL value.

Fixes: a20f997010c4 ("net: dsa: Don't instantiate phylink for CPU/DSA ports unless needed")
Signed-off-by: Miaoqian Lin <linmq006@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
---
 net/dsa/port.c | 2 ++
 1 file changed, 2 insertions(+)

(limited to 'net/dsa')

diff --git a/net/dsa/port.c b/net/dsa/port.c
index 32d472a82241..cdc56ba11f52 100644
--- a/net/dsa/port.c
+++ b/net/dsa/port.c
@@ -1620,8 +1620,10 @@ int dsa_port_link_register_of(struct dsa_port *dp)
 			if (ds->ops->phylink_mac_link_down)
 				ds->ops->phylink_mac_link_down(ds, port,
 					MLO_AN_FIXED, PHY_INTERFACE_MODE_NA);
+			of_node_put(phy_np);
 			return dsa_port_phylink_register(dp);
 		}
+		of_node_put(phy_np);
 		return 0;
 	}
 
-- 
cgit v1.2.3


From 7c762e70c50b462fabe44a597e2a6c3e56c236c0 Mon Sep 17 00:00:00 2001
From: Vladimir Oltean <vladimir.oltean@nxp.com>
Date: Fri, 22 Apr 2022 01:42:22 +0300
Subject: net: dsa: flood multicast to CPU when slave has IFF_PROMISC

Certain DSA switches can eliminate flooding to the CPU when none of the
ports have the IFF_ALLMULTI or IFF_PROMISC flags set. This is done by
synthesizing a call to dsa_port_bridge_flags() for the CPU port, a call
which normally comes from the bridge driver via switchdev.

The bridge port flags and IFF_PROMISC|IFF_ALLMULTI have slightly
different semantics, and due to inattention/lack of proper testing, the
IFF_PROMISC flag allows unknown unicast to be flooded to the CPU, but
not unknown multicast.

This must be fixed by setting both BR_FLOOD (unicast) and BR_MCAST_FLOOD
in the synthesized dsa_port_bridge_flags() call, since IFF_PROMISC means
that packets should not be filtered regardless of their MAC DA.

Fixes: 7569459a52c9 ("net: dsa: manage flooding on the CPU ports")
Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
---
 net/dsa/slave.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

(limited to 'net/dsa')

diff --git a/net/dsa/slave.c b/net/dsa/slave.c
index 41c69a6e7854..8022d50584db 100644
--- a/net/dsa/slave.c
+++ b/net/dsa/slave.c
@@ -285,7 +285,7 @@ static void dsa_port_manage_cpu_flood(struct dsa_port *dp)
 		if (other_dp->slave->flags & IFF_ALLMULTI)
 			flags.val |= BR_MCAST_FLOOD;
 		if (other_dp->slave->flags & IFF_PROMISC)
-			flags.val |= BR_FLOOD;
+			flags.val |= BR_FLOOD | BR_MCAST_FLOOD;
 	}
 
 	err = dsa_port_pre_bridge_flags(dp, flags, NULL);
-- 
cgit v1.2.3