target/linux/armsr/patches-6.1/701-v6.2-0011-net-dpaa2-switch-serialize-changes-to-priv-mac-with.patch

   1 From 80d12452a5f160c39d63efc1be07df36f9d07133 Mon Sep 17 00:00:00 2001
   2 From: Vladimir Oltean <vladimir.oltean@nxp.com>
   3 Date: Tue, 29 Nov 2022 16:12:20 +0200
   4 Subject: [PATCH 13/14] net: dpaa2-switch: serialize changes to priv->mac with
   5  a mutex
   6
   7 The dpaa2-switch driver uses a DPMAC in the same way as the dpaa2-eth
   8 driver, so we need to duplicate the locking solution established by the
   9 previous change to the switch driver as well.
  10
  11 Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
  12 Reviewed-by: Ioana Ciornei <ioana.ciornei@nxp.com>
  13 Tested-by: Ioana Ciornei <ioana.ciornei@nxp.com>
  14 Signed-off-by: Paolo Abeni <pabeni@redhat.com>
  15 ---
  16  .../freescale/dpaa2/dpaa2-switch-ethtool.c    | 32 +++++++++++++++----
  17  .../ethernet/freescale/dpaa2/dpaa2-switch.c   | 31 ++++++++++++++++--
  18  .../ethernet/freescale/dpaa2/dpaa2-switch.h   |  2 ++
  19  3 files changed, 55 insertions(+), 10 deletions(-)
  20
  21 --- a/drivers/net/ethernet/freescale/dpaa2/dpaa2-switch-ethtool.c
  22 +++ b/drivers/net/ethernet/freescale/dpaa2/dpaa2-switch-ethtool.c
  23 @@ -60,11 +60,18 @@ dpaa2_switch_get_link_ksettings(struct n
  24  {
  25         struct ethsw_port_priv *port_priv = netdev_priv(netdev);
  26         struct dpsw_link_state state = {0};
  27 -       int err = 0;
  28 +       int err;
  29
  30 -       if (dpaa2_switch_port_is_type_phy(port_priv))
  31 -               return phylink_ethtool_ksettings_get(port_priv->mac->phylink,
  32 -                                                    link_ksettings);
  33 +       mutex_lock(&port_priv->mac_lock);
  34 +
  35 +       if (dpaa2_switch_port_is_type_phy(port_priv)) {
  36 +               err = phylink_ethtool_ksettings_get(port_priv->mac->phylink,
  37 +                                                   link_ksettings);
  38 +               mutex_unlock(&port_priv->mac_lock);
  39 +               return err;
  40 +       }
  41 +
  42 +       mutex_unlock(&port_priv->mac_lock);
  43
  44         err = dpsw_if_get_link_state(port_priv->ethsw_data->mc_io, 0,
  45                                      port_priv->ethsw_data->dpsw_handle,
  46 @@ -99,9 +106,16 @@ dpaa2_switch_set_link_ksettings(struct n
  47         bool if_running;
  48         int err = 0, ret;
  49
  50 -       if (dpaa2_switch_port_is_type_phy(port_priv))
  51 -               return phylink_ethtool_ksettings_set(port_priv->mac->phylink,
  52 -                                                    link_ksettings);
  53 +       mutex_lock(&port_priv->mac_lock);
  54 +
  55 +       if (dpaa2_switch_port_is_type_phy(port_priv)) {
  56 +               err = phylink_ethtool_ksettings_set(port_priv->mac->phylink,
  57 +                                                   link_ksettings);
  58 +               mutex_unlock(&port_priv->mac_lock);
  59 +               return err;
  60 +       }
  61 +
  62 +       mutex_unlock(&port_priv->mac_lock);
  63
  64         /* Interface needs to be down to change link settings */
  65         if_running = netif_running(netdev);
  66 @@ -189,8 +203,12 @@ static void dpaa2_switch_ethtool_get_sta
  67                                    dpaa2_switch_ethtool_counters[i].name, err);
  68         }
  69
  70 +       mutex_lock(&port_priv->mac_lock);
  71 +
  72         if (dpaa2_switch_port_has_mac(port_priv))
  73                 dpaa2_mac_get_ethtool_stats(port_priv->mac, data + i);
  74 +
  75 +       mutex_unlock(&port_priv->mac_lock);
  76  }
  77
  78  const struct ethtool_ops dpaa2_switch_port_ethtool_ops = {
  79 --- a/drivers/net/ethernet/freescale/dpaa2/dpaa2-switch.c
  80 +++ b/drivers/net/ethernet/freescale/dpaa2/dpaa2-switch.c
  81 @@ -603,8 +603,11 @@ static int dpaa2_switch_port_link_state_
  82
  83         /* When we manage the MAC/PHY using phylink there is no need
  84          * to manually update the netif_carrier.
  85 +        * We can avoid locking because we are called from the "link changed"
  86 +        * IRQ handler, which is the same as the "endpoint changed" IRQ handler
  87 +        * (the writer to port_priv->mac), so we cannot race with it.
  88          */
  89 -       if (dpaa2_switch_port_is_type_phy(port_priv))
  90 +       if (dpaa2_mac_is_type_phy(port_priv->mac))
  91                 return 0;
  92
  93         /* Interrupts are received even though no one issued an 'ifconfig up'
  94 @@ -684,6 +687,8 @@ static int dpaa2_switch_port_open(struct
  95         struct ethsw_core *ethsw = port_priv->ethsw_data;
  96         int err;
  97
  98 +       mutex_lock(&port_priv->mac_lock);
  99 +
 100         if (!dpaa2_switch_port_is_type_phy(port_priv)) {
 101                 /* Explicitly set carrier off, otherwise
 102                  * netif_carrier_ok() will return true and cause 'ip link show'
 103 @@ -697,6 +702,7 @@ static int dpaa2_switch_port_open(struct
 104                              port_priv->ethsw_data->dpsw_handle,
 105                              port_priv->idx);
 106         if (err) {
 107 +               mutex_unlock(&port_priv->mac_lock);
 108                 netdev_err(netdev, "dpsw_if_enable err %d\n", err);
 109                 return err;
 110         }
 111 @@ -706,6 +712,8 @@ static int dpaa2_switch_port_open(struct
 112         if (dpaa2_switch_port_is_type_phy(port_priv))
 113                 dpaa2_mac_start(port_priv->mac);
 114
 115 +       mutex_unlock(&port_priv->mac_lock);
 116 +
 117         return 0;
 118  }
 119
 120 @@ -715,6 +723,8 @@ static int dpaa2_switch_port_stop(struct
 121         struct ethsw_core *ethsw = port_priv->ethsw_data;
 122         int err;
 123
 124 +       mutex_lock(&port_priv->mac_lock);
 125 +
 126         if (dpaa2_switch_port_is_type_phy(port_priv)) {
 127                 dpaa2_mac_stop(port_priv->mac);
 128         } else {
 129 @@ -722,6 +732,8 @@ static int dpaa2_switch_port_stop(struct
 130                 netif_carrier_off(netdev);
 131         }
 132
 133 +       mutex_unlock(&port_priv->mac_lock);
 134 +
 135         err = dpsw_if_disable(port_priv->ethsw_data->mc_io, 0,
 136                               port_priv->ethsw_data->dpsw_handle,
 137                               port_priv->idx);
 138 @@ -1461,7 +1473,9 @@ static int dpaa2_switch_port_connect_mac
 139                 }
 140         }
 141
 142 +       mutex_lock(&port_priv->mac_lock);
 143         port_priv->mac = mac;
 144 +       mutex_unlock(&port_priv->mac_lock);
 145
 146         return 0;
 147
 148 @@ -1474,9 +1488,12 @@ err_free_mac:
 149
 150  static void dpaa2_switch_port_disconnect_mac(struct ethsw_port_priv *port_priv)
 151  {
 152 -       struct dpaa2_mac *mac = port_priv->mac;
 153 +       struct dpaa2_mac *mac;
 154
 155 +       mutex_lock(&port_priv->mac_lock);
 156 +       mac = port_priv->mac;
 157         port_priv->mac = NULL;
 158 +       mutex_unlock(&port_priv->mac_lock);
 159
 160         if (!mac)
 161                 return;
 162 @@ -1495,6 +1512,7 @@ static irqreturn_t dpaa2_switch_irq0_han
 163         struct ethsw_port_priv *port_priv;
 164         u32 status = ~0;
 165         int err, if_id;
 166 +       bool had_mac;
 167
 168         err = dpsw_get_irq_status(ethsw->mc_io, 0, ethsw->dpsw_handle,
 169                                   DPSW_IRQ_INDEX_IF, &status);
 170 @@ -1513,7 +1531,12 @@ static irqreturn_t dpaa2_switch_irq0_han
 171
 172         if (status & DPSW_IRQ_EVENT_ENDPOINT_CHANGED) {
 173                 rtnl_lock();
 174 -               if (dpaa2_switch_port_has_mac(port_priv))
 175 +               /* We can avoid locking because the "endpoint changed" IRQ
 176 +                * handler is the only one who changes priv->mac at runtime,
 177 +                * so we are not racing with anyone.
 178 +                */
 179 +               had_mac = !!port_priv->mac;
 180 +               if (had_mac)
 181                         dpaa2_switch_port_disconnect_mac(port_priv);
 182                 else
 183                         dpaa2_switch_port_connect_mac(port_priv);
 184 @@ -3249,6 +3272,8 @@ static int dpaa2_switch_probe_port(struc
 185         port_priv->netdev = port_netdev;
 186         port_priv->ethsw_data = ethsw;
 187
 188 +       mutex_init(&port_priv->mac_lock);
 189 +
 190         port_priv->idx = port_idx;
 191         port_priv->stp_state = BR_STATE_FORWARDING;
 192
 193 --- a/drivers/net/ethernet/freescale/dpaa2/dpaa2-switch.h
 194 +++ b/drivers/net/ethernet/freescale/dpaa2/dpaa2-switch.h
 195 @@ -161,6 +161,8 @@ struct ethsw_port_priv {
 196
 197         struct dpaa2_switch_filter_block *filter_block;
 198         struct dpaa2_mac        *mac;
 199 +       /* Protects against changes to port_priv->mac */
 200 +       struct mutex            mac_lock;
 201  };
 202
 203  /* Switch data */