net/dsa/switch.c

   1 // SPDX-License-Identifier: GPL-2.0-or-later
   2 /*
   3  * Handling of a single switch chip, part of a switch fabric
   4  *
   5  * Copyright (c) 2017 Savoir-faire Linux Inc.
   6  *      Vivien Didelot <[email protected]>
   7  */
   8
   9 #include <linux/if_bridge.h>
  10 #include <linux/netdevice.h>
  11 #include <linux/notifier.h>
  12 #include <linux/if_vlan.h>
  13 #include <net/switchdev.h>
  14
  15 #include "dsa_priv.h"
  16
  17 static unsigned int dsa_switch_fastest_ageing_time(struct dsa_switch *ds,
  18                                                    unsigned int ageing_time)
  19 {
  20         int i;
  21
  22         for (i = 0; i < ds->num_ports; ++i) {
  23                 struct dsa_port *dp = dsa_to_port(ds, i);
  24
  25                 if (dp->ageing_time && dp->ageing_time < ageing_time)
  26                         ageing_time = dp->ageing_time;
  27         }
  28
  29         return ageing_time;
  30 }
  31
  32 static int dsa_switch_ageing_time(struct dsa_switch *ds,
  33                                   struct dsa_notifier_ageing_time_info *info)
  34 {
  35         unsigned int ageing_time = info->ageing_time;
  36         struct switchdev_trans *trans = info->trans;
  37
  38         if (switchdev_trans_ph_prepare(trans)) {
  39                 if (ds->ageing_time_min && ageing_time < ds->ageing_time_min)
  40                         return -ERANGE;
  41                 if (ds->ageing_time_max && ageing_time > ds->ageing_time_max)
  42                         return -ERANGE;
  43                 return 0;
  44         }
  45
  46         /* Program the fastest ageing time in case of multiple bridges */
  47         ageing_time = dsa_switch_fastest_ageing_time(ds, ageing_time);
  48
  49         if (ds->ops->set_ageing_time)
  50                 return ds->ops->set_ageing_time(ds, ageing_time);
  51
  52         return 0;
  53 }
  54
  55 static int dsa_switch_bridge_join(struct dsa_switch *ds,
  56                                   struct dsa_notifier_bridge_info *info)
  57 {
  58         if (ds->index == info->sw_index && ds->ops->port_bridge_join)
  59                 return ds->ops->port_bridge_join(ds, info->port, info->br);
  60
  61         if (ds->index != info->sw_index && ds->ops->crosschip_bridge_join)
  62                 return ds->ops->crosschip_bridge_join(ds, info->sw_index,
  63                                                       info->port, info->br);
  64
  65         return 0;
  66 }
  67
  68 static int dsa_switch_bridge_leave(struct dsa_switch *ds,
  69                                    struct dsa_notifier_bridge_info *info)
  70 {
  71         bool unset_vlan_filtering = br_vlan_enabled(info->br);
  72         int err, i;
  73
  74         if (ds->index == info->sw_index && ds->ops->port_bridge_leave)
  75                 ds->ops->port_bridge_leave(ds, info->port, info->br);
  76
  77         if (ds->index != info->sw_index && ds->ops->crosschip_bridge_leave)
  78                 ds->ops->crosschip_bridge_leave(ds, info->sw_index, info->port,
  79                                                 info->br);
  80
  81         /* If the bridge was vlan_filtering, the bridge core doesn't trigger an
  82          * event for changing vlan_filtering setting upon slave ports leaving
  83          * it. That is a good thing, because that lets us handle it and also
  84          * handle the case where the switch's vlan_filtering setting is global
  85          * (not per port). When that happens, the correct moment to trigger the
  86          * vlan_filtering callback is only when the last port left this bridge.
  87          */
  88         if (unset_vlan_filtering && ds->vlan_filtering_is_global) {
  89                 for (i = 0; i < ds->num_ports; i++) {
  90                         if (i == info->port)
  91                                 continue;
  92                         if (dsa_to_port(ds, i)->bridge_dev == info->br) {
  93                                 unset_vlan_filtering = false;
  94                                 break;
  95                         }
  96                 }
  97         }
  98         if (unset_vlan_filtering) {
  99                 struct switchdev_trans trans = {0};
 100
 101                 err = dsa_port_vlan_filtering(dsa_to_port(ds, info->port),
 102                                               false, &trans);
 103                 if (err && err != EOPNOTSUPP)
 104                         return err;
 105         }
 106         return 0;
 107 }
 108
 109 static int dsa_switch_fdb_add(struct dsa_switch *ds,
 110                               struct dsa_notifier_fdb_info *info)
 111 {
 112         int port = dsa_towards_port(ds, info->sw_index, info->port);
 113
 114         if (!ds->ops->port_fdb_add)
 115                 return -EOPNOTSUPP;
 116
 117         return ds->ops->port_fdb_add(ds, port, info->addr, info->vid);
 118 }
 119
 120 static int dsa_switch_fdb_del(struct dsa_switch *ds,
 121                               struct dsa_notifier_fdb_info *info)
 122 {
 123         int port = dsa_towards_port(ds, info->sw_index, info->port);
 124
 125         if (!ds->ops->port_fdb_del)
 126                 return -EOPNOTSUPP;
 127
 128         return ds->ops->port_fdb_del(ds, port, info->addr, info->vid);
 129 }
 130
 131 static bool dsa_switch_mdb_match(struct dsa_switch *ds, int port,
 132                                  struct dsa_notifier_mdb_info *info)
 133 {
 134         if (ds->index == info->sw_index && port == info->port)
 135                 return true;
 136
 137         if (dsa_is_dsa_port(ds, port))
 138                 return true;
 139
 140         return false;
 141 }
 142
 143 static int dsa_switch_mdb_prepare(struct dsa_switch *ds,
 144                                   struct dsa_notifier_mdb_info *info)
 145 {
 146         int port, err;
 147
 148         if (!ds->ops->port_mdb_prepare || !ds->ops->port_mdb_add)
 149                 return -EOPNOTSUPP;
 150
 151         for (port = 0; port < ds->num_ports; port++) {
 152                 if (dsa_switch_mdb_match(ds, port, info)) {
 153                         err = ds->ops->port_mdb_prepare(ds, port, info->mdb);
 154                         if (err)
 155                                 return err;
 156                 }
 157         }
 158
 159         return 0;
 160 }
 161
 162 static int dsa_switch_mdb_add(struct dsa_switch *ds,
 163                               struct dsa_notifier_mdb_info *info)
 164 {
 165         int port;
 166
 167         if (switchdev_trans_ph_prepare(info->trans))
 168                 return dsa_switch_mdb_prepare(ds, info);
 169
 170         if (!ds->ops->port_mdb_add)
 171                 return 0;
 172
 173         for (port = 0; port < ds->num_ports; port++)
 174                 if (dsa_switch_mdb_match(ds, port, info))
 175                         ds->ops->port_mdb_add(ds, port, info->mdb);
 176
 177         return 0;
 178 }
 179
 180 static int dsa_switch_mdb_del(struct dsa_switch *ds,
 181                               struct dsa_notifier_mdb_info *info)
 182 {
 183         if (!ds->ops->port_mdb_del)
 184                 return -EOPNOTSUPP;
 185
 186         if (ds->index == info->sw_index)
 187                 return ds->ops->port_mdb_del(ds, info->port, info->mdb);
 188
 189         return 0;
 190 }
 191
 192 static int dsa_port_vlan_device_check(struct net_device *vlan_dev,
 193                                       int vlan_dev_vid,
 194                                       void *arg)
 195 {
 196         struct switchdev_obj_port_vlan *vlan = arg;
 197         u16 vid;
 198
 199         for (vid = vlan->vid_begin; vid <= vlan->vid_end; ++vid) {
 200                 if (vid == vlan_dev_vid)
 201                         return -EBUSY;
 202         }
 203
 204         return 0;
 205 }
 206
 207 static int dsa_port_vlan_check(struct dsa_switch *ds, int port,
 208                                const struct switchdev_obj_port_vlan *vlan)
 209 {
 210         const struct dsa_port *dp = dsa_to_port(ds, port);
 211         int err = 0;
 212
 213         /* Device is not bridged, let it proceed with the VLAN device
 214          * creation.
 215          */
 216         if (!dp->bridge_dev)
 217                 return err;
 218
 219         /* dsa_slave_vlan_rx_{add,kill}_vid() cannot use the prepare phase and
 220          * already checks whether there is an overlapping bridge VLAN entry
 221          * with the same VID, so here we only need to check that if we are
 222          * adding a bridge VLAN entry there is not an overlapping VLAN device
 223          * claiming that VID.
 224          */
 225         return vlan_for_each(dp->slave, dsa_port_vlan_device_check,
 226                              (void *)vlan);
 227 }
 228
 229 static bool dsa_switch_vlan_match(struct dsa_switch *ds, int port,
 230                                   struct dsa_notifier_vlan_info *info)
 231 {
 232         if (ds->index == info->sw_index && port == info->port)
 233                 return true;
 234
 235         if (dsa_is_dsa_port(ds, port))
 236                 return true;
 237
 238         return false;
 239 }
 240
 241 static int dsa_switch_vlan_prepare(struct dsa_switch *ds,
 242                                    struct dsa_notifier_vlan_info *info)
 243 {
 244         int port, err;
 245
 246         if (!ds->ops->port_vlan_prepare || !ds->ops->port_vlan_add)
 247                 return -EOPNOTSUPP;
 248
 249         for (port = 0; port < ds->num_ports; port++) {
 250                 if (dsa_switch_vlan_match(ds, port, info)) {
 251                         err = dsa_port_vlan_check(ds, port, info->vlan);
 252                         if (err)
 253                                 return err;
 254
 255                         err = ds->ops->port_vlan_prepare(ds, port, info->vlan);
 256                         if (err)
 257                                 return err;
 258                 }
 259         }
 260
 261         return 0;
 262 }
 263
 264 static int dsa_switch_vlan_add(struct dsa_switch *ds,
 265                                struct dsa_notifier_vlan_info *info)
 266 {
 267         int port;
 268
 269         if (switchdev_trans_ph_prepare(info->trans))
 270                 return dsa_switch_vlan_prepare(ds, info);
 271
 272         if (!ds->ops->port_vlan_add)
 273                 return 0;
 274
 275         for (port = 0; port < ds->num_ports; port++)
 276                 if (dsa_switch_vlan_match(ds, port, info))
 277                         ds->ops->port_vlan_add(ds, port, info->vlan);
 278
 279         return 0;
 280 }
 281
 282 static int dsa_switch_vlan_del(struct dsa_switch *ds,
 283                                struct dsa_notifier_vlan_info *info)
 284 {
 285         if (!ds->ops->port_vlan_del)
 286                 return -EOPNOTSUPP;
 287
 288         if (ds->index == info->sw_index)
 289                 return ds->ops->port_vlan_del(ds, info->port, info->vlan);
 290
 291         /* Do not deprogram the DSA links as they may be used as conduit
 292          * for other VLAN members in the fabric.
 293          */
 294         return 0;
 295 }
 296
 297 static int dsa_switch_event(struct notifier_block *nb,
 298                             unsigned long event, void *info)
 299 {
 300         struct dsa_switch *ds = container_of(nb, struct dsa_switch, nb);
 301         int err;
 302
 303         switch (event) {
 304         case DSA_NOTIFIER_AGEING_TIME:
 305                 err = dsa_switch_ageing_time(ds, info);
 306                 break;
 307         case DSA_NOTIFIER_BRIDGE_JOIN:
 308                 err = dsa_switch_bridge_join(ds, info);
 309                 break;
 310         case DSA_NOTIFIER_BRIDGE_LEAVE:
 311                 err = dsa_switch_bridge_leave(ds, info);
 312                 break;
 313         case DSA_NOTIFIER_FDB_ADD:
 314                 err = dsa_switch_fdb_add(ds, info);
 315                 break;
 316         case DSA_NOTIFIER_FDB_DEL:
 317                 err = dsa_switch_fdb_del(ds, info);
 318                 break;
 319         case DSA_NOTIFIER_MDB_ADD:
 320                 err = dsa_switch_mdb_add(ds, info);
 321                 break;
 322         case DSA_NOTIFIER_MDB_DEL:
 323                 err = dsa_switch_mdb_del(ds, info);
 324                 break;
 325         case DSA_NOTIFIER_VLAN_ADD:
 326                 err = dsa_switch_vlan_add(ds, info);
 327                 break;
 328         case DSA_NOTIFIER_VLAN_DEL:
 329                 err = dsa_switch_vlan_del(ds, info);
 330                 break;
 331         default:
 332                 err = -EOPNOTSUPP;
 333                 break;
 334         }
 335
 336         /* Non-switchdev operations cannot be rolled back. If a DSA driver
 337          * returns an error during the chained call, switch chips may be in an
 338          * inconsistent state.
 339          */
 340         if (err)
 341                 dev_dbg(ds->dev, "breaking chain for DSA event %lu (%d)\n",
 342                         event, err);
 343
 344         return notifier_from_errno(err);
 345 }
 346
 347 int dsa_switch_register_notifier(struct dsa_switch *ds)
 348 {
 349         ds->nb.notifier_call = dsa_switch_event;
 350
 351         return raw_notifier_chain_register(&ds->dst->nh, &ds->nb);
 352 }
 353
 354 void dsa_switch_unregister_notifier(struct dsa_switch *ds)
 355 {
 356         int err;
 357
 358         err = raw_notifier_chain_unregister(&ds->dst->nh, &ds->nb);
 359         if (err)
 360                 dev_err(ds->dev, "failed to unregister notifier (%d)\n", err);
 361 }