net/dsa/switch.c

   1 /*
   2  * Handling of a single switch chip, part of a switch fabric
   3  *
   4  * Copyright (c) 2017 Vivien Didelot <vivien.didelot@savoirfairelinux.com>
   5  *
   6  * This program is free software; you can redistribute it and/or modify
   7  * it under the terms of the GNU General Public License as published by
   8  * the Free Software Foundation; either version 2 of the License, or
   9  * (at your option) any later version.
  10  */
  11
  12 #include <linux/netdevice.h>
  13 #include <linux/notifier.h>
  14 #include <net/dsa.h>
  15
  16 static int dsa_switch_bridge_join(struct dsa_switch *ds,
  17                                   struct dsa_notifier_bridge_info *info)
  18 {
  19         if (ds->index == info->sw_index && ds->ops->port_bridge_join)
  20                 return ds->ops->port_bridge_join(ds, info->port, info->br);
  21
  22         if (ds->index != info->sw_index)
  23                 dev_dbg(ds->dev, "crosschip DSA port %d.%d bridged to %s\n",
  24                         info->sw_index, info->port, netdev_name(info->br));
  25
  26         return 0;
  27 }
  28
  29 static int dsa_switch_bridge_leave(struct dsa_switch *ds,
  30                                    struct dsa_notifier_bridge_info *info)
  31 {
  32         if (ds->index == info->sw_index && ds->ops->port_bridge_leave)
  33                 ds->ops->port_bridge_leave(ds, info->port, info->br);
  34
  35         if (ds->index != info->sw_index)
  36                 dev_dbg(ds->dev, "crosschip DSA port %d.%d unbridged from %s\n",
  37                         info->sw_index, info->port, netdev_name(info->br));
  38
  39         return 0;
  40 }
  41
  42 static int dsa_switch_event(struct notifier_block *nb,
  43                             unsigned long event, void *info)
  44 {
  45         struct dsa_switch *ds = container_of(nb, struct dsa_switch, nb);
  46         int err;
  47
  48         switch (event) {
  49         case DSA_NOTIFIER_BRIDGE_JOIN:
  50                 err = dsa_switch_bridge_join(ds, info);
  51                 break;
  52         case DSA_NOTIFIER_BRIDGE_LEAVE:
  53                 err = dsa_switch_bridge_leave(ds, info);
  54                 break;
  55         default:
  56                 err = -EOPNOTSUPP;
  57                 break;
  58         }
  59
  60         /* Non-switchdev operations cannot be rolled back. If a DSA driver
  61          * returns an error during the chained call, switch chips may be in an
  62          * inconsistent state.
  63          */
  64         if (err)
  65                 dev_dbg(ds->dev, "breaking chain for DSA event %lu (%d)\n",
  66                         event, err);
  67
  68         return notifier_from_errno(err);
  69 }
  70
  71 int dsa_switch_register_notifier(struct dsa_switch *ds)
  72 {
  73         ds->nb.notifier_call = dsa_switch_event;
  74
  75         return raw_notifier_chain_register(&ds->dst->nh, &ds->nb);
  76 }
  77
  78 void dsa_switch_unregister_notifier(struct dsa_switch *ds)
  79 {
  80         int err;
  81
  82         err = raw_notifier_chain_unregister(&ds->dst->nh, &ds->nb);
  83         if (err)
  84                 dev_err(ds->dev, "failed to unregister notifier (%d)\n", err);
  85 }