Merge branch 'mlxsw-fixes'

Petr Machata says:

====================
mlxsw: Fixes for PTP support

This set fixes several issues in mlxsw PTP code.

- Patch #1 fixes compilation warnings.

- Patch #2 adjusts the order of operation during cleanup, thereby
  closing the window after PTP state was already cleaned in the ASIC
  for the given port, but before the port is removed, when the user
  could still in theory make changes to the configuration.

- Patch #3 protects the PTP configuration with a custom mutex, instead
  of relying on RTNL, which is not held in all access paths.

- Patch #4 forbids enablement of PTP only in RX or only in TX. The
  driver implicitly assumed this would be the case, but neglected to
  sanitize the configuration.
====================

Signed-off-by: David S. Miller <davem@davemloft.net>

3 files changed, 34 insertions, 16 deletions

diff --git a/drivers/net/ethernet/mellanox/mlxsw/spectrum.c b/drivers/net/ethernet/mellanox/mlxsw/spectrum.c
index 1e240cdd9cbd..30c7b0e15721 100644
--- a/drivers/net/ethernet/mellanox/mlxsw/spectrum.c
+++ b/drivers/net/ethernet/mellanox/mlxsw/spectrum.c
@@ -1897,9 +1897,9 @@ static void mlxsw_sp_port_remove(struct mlxsw_sp *mlxsw_sp, u16 local_port)
 
 	cancel_delayed_work_sync(&mlxsw_sp_port->periodic_hw_stats.update_dw);
 	cancel_delayed_work_sync(&mlxsw_sp_port->ptp.shaper_dw);
-	mlxsw_sp_port_ptp_clear(mlxsw_sp_port);
 	mlxsw_core_port_clear(mlxsw_sp->core, local_port, mlxsw_sp);
 	unregister_netdev(mlxsw_sp_port->dev); /* This calls ndo_stop */
+	mlxsw_sp_port_ptp_clear(mlxsw_sp_port);
 	mlxsw_sp_port_vlan_classification_set(mlxsw_sp_port, true, true);
 	mlxsw_sp->ports[local_port] = NULL;
 	mlxsw_sp_port_vlan_flush(mlxsw_sp_port, true);
diff --git a/drivers/net/ethernet/mellanox/mlxsw/spectrum_ptp.c b/drivers/net/ethernet/mellanox/mlxsw/spectrum_ptp.c
index 2e0b704b8a31..7b01b9c20722 100644
--- a/drivers/net/ethernet/mellanox/mlxsw/spectrum_ptp.c
+++ b/drivers/net/ethernet/mellanox/mlxsw/spectrum_ptp.c
@@ -46,6 +46,7 @@ struct mlxsw_sp2_ptp_state {
 					  * enabled.
 					  */
 	struct hwtstamp_config config;
+	struct mutex lock; /* Protects 'config' and HW configuration. */
 };
 
 struct mlxsw_sp1_ptp_key {
@@ -1374,6 +1375,7 @@ struct mlxsw_sp_ptp_state *mlxsw_sp2_ptp_init(struct mlxsw_sp *mlxsw_sp)
 		goto err_ptp_traps_set;
 
 	refcount_set(&ptp_state->ptp_port_enabled_ref, 0);
+	mutex_init(&ptp_state->lock);
 	return &ptp_state->common;
 
 err_ptp_traps_set:
@@ -1388,6 +1390,7 @@ void mlxsw_sp2_ptp_fini(struct mlxsw_sp_ptp_state *ptp_state_common)
 
 	ptp_state = mlxsw_sp2_ptp_state(mlxsw_sp);
 
+	mutex_destroy(&ptp_state->lock);
 	mlxsw_sp_ptp_traps_unset(mlxsw_sp);
 	kfree(ptp_state);
 }
@@ -1461,7 +1464,10 @@ int mlxsw_sp2_ptp_hwtstamp_get(struct mlxsw_sp_port *mlxsw_sp_port,
 
 	ptp_state = mlxsw_sp2_ptp_state(mlxsw_sp_port->mlxsw_sp);
 
+	mutex_lock(&ptp_state->lock);
 	*config = ptp_state->config;
+	mutex_unlock(&ptp_state->lock);
+
 	return 0;
 }
 
@@ -1523,6 +1529,9 @@ mlxsw_sp2_ptp_get_message_types(const struct hwtstamp_config *config,
 		return -EINVAL;
 	}
 
+	if ((ing_types && !egr_types) || (!ing_types && egr_types))
+		return -EINVAL;
+
 	*p_ing_types = ing_types;
 	*p_egr_types = egr_types;
 	return 0;
@@ -1574,8 +1583,6 @@ static int mlxsw_sp2_ptp_configure_port(struct mlxsw_sp_port *mlxsw_sp_port,
 	struct mlxsw_sp2_ptp_state *ptp_state;
 	int err;
 
-	ASSERT_RTNL();
-
 	ptp_state = mlxsw_sp2_ptp_state(mlxsw_sp_port->mlxsw_sp);
 
 	if (refcount_inc_not_zero(&ptp_state->ptp_port_enabled_ref))
@@ -1597,8 +1604,6 @@ static int mlxsw_sp2_ptp_deconfigure_port(struct mlxsw_sp_port *mlxsw_sp_port,
 	struct mlxsw_sp2_ptp_state *ptp_state;
 	int err;
 
-	ASSERT_RTNL();
-
 	ptp_state = mlxsw_sp2_ptp_state(mlxsw_sp_port->mlxsw_sp);
 
 	if (!refcount_dec_and_test(&ptp_state->ptp_port_enabled_ref))
@@ -1618,16 +1623,20 @@ err_ptp_disable:
 int mlxsw_sp2_ptp_hwtstamp_set(struct mlxsw_sp_port *mlxsw_sp_port,
 			       struct hwtstamp_config *config)
 {
+	struct mlxsw_sp2_ptp_state *ptp_state;
 	enum hwtstamp_rx_filters rx_filter;
 	struct hwtstamp_config new_config;
 	u16 new_ing_types, new_egr_types;
 	bool ptp_enabled;
 	int err;
 
+	ptp_state = mlxsw_sp2_ptp_state(mlxsw_sp_port->mlxsw_sp);
+	mutex_lock(&ptp_state->lock);
+
 	err = mlxsw_sp2_ptp_get_message_types(config, &new_ing_types,
 					      &new_egr_types, &rx_filter);
 	if (err)
-		return err;
+		goto err_get_message_types;
 
 	new_config.flags = config->flags;
 	new_config.tx_type = config->tx_type;
@@ -1640,11 +1649,11 @@ int mlxsw_sp2_ptp_hwtstamp_set(struct mlxsw_sp_port *mlxsw_sp_port,
 		err = mlxsw_sp2_ptp_configure_port(mlxsw_sp_port, new_ing_types,
 						   new_egr_types, new_config);
 		if (err)
-			return err;
+			goto err_configure_port;
 	} else if (!new_ing_types && !new_egr_types && ptp_enabled) {
 		err = mlxsw_sp2_ptp_deconfigure_port(mlxsw_sp_port, new_config);
 		if (err)
-			return err;
+			goto err_deconfigure_port;
 	}
 
 	mlxsw_sp_port->ptp.ing_types = new_ing_types;
@@ -1652,8 +1661,15 @@ int mlxsw_sp2_ptp_hwtstamp_set(struct mlxsw_sp_port *mlxsw_sp_port,
 
 	/* Notify the ioctl caller what we are actually timestamping. */
 	config->rx_filter = rx_filter;
+	mutex_unlock(&ptp_state->lock);
 
 	return 0;
+
+err_deconfigure_port:
+err_configure_port:
+err_get_message_types:
+	mutex_unlock(&ptp_state->lock);
+	return err;
 }
 
 int mlxsw_sp2_ptp_get_ts_info(struct mlxsw_sp *mlxsw_sp,
diff --git a/drivers/net/ethernet/mellanox/mlxsw/spectrum_ptp.h b/drivers/net/ethernet/mellanox/mlxsw/spectrum_ptp.h
index 2d1628fdefc1..a8b88230959a 100644
--- a/drivers/net/ethernet/mellanox/mlxsw/spectrum_ptp.h
+++ b/drivers/net/ethernet/mellanox/mlxsw/spectrum_ptp.h
@@ -171,10 +171,11 @@ static inline void mlxsw_sp1_get_stats(struct mlxsw_sp_port *mlxsw_sp_port,
 {
 }
 
-int mlxsw_sp_ptp_txhdr_construct(struct mlxsw_core *mlxsw_core,
-				 struct mlxsw_sp_port *mlxsw_sp_port,
-				 struct sk_buff *skb,
-				 const struct mlxsw_tx_info *tx_info)
+static inline int
+mlxsw_sp_ptp_txhdr_construct(struct mlxsw_core *mlxsw_core,
+			     struct mlxsw_sp_port *mlxsw_sp_port,
+			     struct sk_buff *skb,
+			     const struct mlxsw_tx_info *tx_info)
 {
 	return -EOPNOTSUPP;
 }
@@ -231,10 +232,11 @@ static inline int mlxsw_sp2_ptp_get_ts_info(struct mlxsw_sp *mlxsw_sp,
 	return mlxsw_sp_ptp_get_ts_info_noptp(info);
 }
 
-int mlxsw_sp2_ptp_txhdr_construct(struct mlxsw_core *mlxsw_core,
-				  struct mlxsw_sp_port *mlxsw_sp_port,
-				  struct sk_buff *skb,
-				  const struct mlxsw_tx_info *tx_info)
+static inline int
+mlxsw_sp2_ptp_txhdr_construct(struct mlxsw_core *mlxsw_core,
+			      struct mlxsw_sp_port *mlxsw_sp_port,
+			      struct sk_buff *skb,
+			      const struct mlxsw_tx_info *tx_info)
 {
 	return -EOPNOTSUPP;
 }