net/dsa/dsa.c

   1 // SPDX-License-Identifier: GPL-2.0-or-later
   2 /*
   3  * net/dsa/dsa.c - Hardware switch handling
   4  * Copyright (c) 2008-2009 Marvell Semiconductor
   5  * Copyright (c) 2013 Florian Fainelli <florian@openwrt.org>
   6  */
   7
   8 #include <linux/device.h>
   9 #include <linux/list.h>
  10 #include <linux/module.h>
  11 #include <linux/netdevice.h>
  12 #include <linux/sysfs.h>
  13 #include <linux/ptp_classify.h>
  14
  15 #include "dsa_priv.h"
  16
  17 static LIST_HEAD(dsa_tag_drivers_list);
  18 static DEFINE_MUTEX(dsa_tag_drivers_lock);
  19
  20 static struct sk_buff *dsa_slave_notag_xmit(struct sk_buff *skb,
  21                                             struct net_device *dev)
  22 {
  23         /* Just return the original SKB */
  24         return skb;
  25 }
  26
  27 static const struct dsa_device_ops none_ops = {
  28         .name   = "none",
  29         .proto  = DSA_TAG_PROTO_NONE,
  30         .xmit   = dsa_slave_notag_xmit,
  31         .rcv    = NULL,
  32 };
  33
  34 DSA_TAG_DRIVER(none_ops);
  35
  36 static void dsa_tag_driver_register(struct dsa_tag_driver *dsa_tag_driver,
  37                                     struct module *owner)
  38 {
  39         dsa_tag_driver->owner = owner;
  40
  41         mutex_lock(&dsa_tag_drivers_lock);
  42         list_add_tail(&dsa_tag_driver->list, &dsa_tag_drivers_list);
  43         mutex_unlock(&dsa_tag_drivers_lock);
  44 }
  45
  46 void dsa_tag_drivers_register(struct dsa_tag_driver *dsa_tag_driver_array[],
  47                               unsigned int count, struct module *owner)
  48 {
  49         unsigned int i;
  50
  51         for (i = 0; i < count; i++)
  52                 dsa_tag_driver_register(dsa_tag_driver_array[i], owner);
  53 }
  54
  55 static void dsa_tag_driver_unregister(struct dsa_tag_driver *dsa_tag_driver)
  56 {
  57         mutex_lock(&dsa_tag_drivers_lock);
  58         list_del(&dsa_tag_driver->list);
  59         mutex_unlock(&dsa_tag_drivers_lock);
  60 }
  61 EXPORT_SYMBOL_GPL(dsa_tag_drivers_register);
  62
  63 void dsa_tag_drivers_unregister(struct dsa_tag_driver *dsa_tag_driver_array[],
  64                                 unsigned int count)
  65 {
  66         unsigned int i;
  67
  68         for (i = 0; i < count; i++)
  69                 dsa_tag_driver_unregister(dsa_tag_driver_array[i]);
  70 }
  71 EXPORT_SYMBOL_GPL(dsa_tag_drivers_unregister);
  72
  73 const char *dsa_tag_protocol_to_str(const struct dsa_device_ops *ops)
  74 {
  75         return ops->name;
  76 };
  77
  78 /* Function takes a reference on the module owning the tagger,
  79  * so dsa_tag_driver_put must be called afterwards.
  80  */
  81 const struct dsa_device_ops *dsa_find_tagger_by_name(const char *buf)
  82 {
  83         const struct dsa_device_ops *ops = ERR_PTR(-ENOPROTOOPT);
  84         struct dsa_tag_driver *dsa_tag_driver;
  85
  86         mutex_lock(&dsa_tag_drivers_lock);
  87         list_for_each_entry(dsa_tag_driver, &dsa_tag_drivers_list, list) {
  88                 const struct dsa_device_ops *tmp = dsa_tag_driver->ops;
  89
  90                 if (!sysfs_streq(buf, tmp->name))
  91                         continue;
  92
  93                 if (!try_module_get(dsa_tag_driver->owner))
  94                         break;
  95
  96                 ops = tmp;
  97                 break;
  98         }
  99         mutex_unlock(&dsa_tag_drivers_lock);
 100
 101         return ops;
 102 }
 103
 104 const struct dsa_device_ops *dsa_tag_driver_get(int tag_protocol)
 105 {
 106         struct dsa_tag_driver *dsa_tag_driver;
 107         const struct dsa_device_ops *ops;
 108         bool found = false;
 109
 110         request_module("%s%d", DSA_TAG_DRIVER_ALIAS, tag_protocol);
 111
 112         mutex_lock(&dsa_tag_drivers_lock);
 113         list_for_each_entry(dsa_tag_driver, &dsa_tag_drivers_list, list) {
 114                 ops = dsa_tag_driver->ops;
 115                 if (ops->proto == tag_protocol) {
 116                         found = true;
 117                         break;
 118                 }
 119         }
 120
 121         if (found) {
 122                 if (!try_module_get(dsa_tag_driver->owner))
 123                         ops = ERR_PTR(-ENOPROTOOPT);
 124         } else {
 125                 ops = ERR_PTR(-ENOPROTOOPT);
 126         }
 127
 128         mutex_unlock(&dsa_tag_drivers_lock);
 129
 130         return ops;
 131 }
 132
 133 void dsa_tag_driver_put(const struct dsa_device_ops *ops)
 134 {
 135         struct dsa_tag_driver *dsa_tag_driver;
 136
 137         mutex_lock(&dsa_tag_drivers_lock);
 138         list_for_each_entry(dsa_tag_driver, &dsa_tag_drivers_list, list) {
 139                 if (dsa_tag_driver->ops == ops) {
 140                         module_put(dsa_tag_driver->owner);
 141                         break;
 142                 }
 143         }
 144         mutex_unlock(&dsa_tag_drivers_lock);
 145 }
 146
 147 static int dev_is_class(struct device *dev, void *class)
 148 {
 149         if (dev->class != NULL && !strcmp(dev->class->name, class))
 150                 return 1;
 151
 152         return 0;
 153 }
 154
 155 static struct device *dev_find_class(struct device *parent, char *class)
 156 {
 157         if (dev_is_class(parent, class)) {
 158                 get_device(parent);
 159                 return parent;
 160         }
 161
 162         return device_find_child(parent, class, dev_is_class);
 163 }
 164
 165 struct net_device *dsa_dev_to_net_device(struct device *dev)
 166 {
 167         struct device *d;
 168
 169         d = dev_find_class(dev, "net");
 170         if (d != NULL) {
 171                 struct net_device *nd;
 172
 173                 nd = to_net_dev(d);
 174                 dev_hold(nd);
 175                 put_device(d);
 176
 177                 return nd;
 178         }
 179
 180         return NULL;
 181 }
 182 EXPORT_SYMBOL_GPL(dsa_dev_to_net_device);
 183
 184 /* Determine if we should defer delivery of skb until we have a rx timestamp.
 185  *
 186  * Called from dsa_switch_rcv. For now, this will only work if tagging is
 187  * enabled on the switch. Normally the MAC driver would retrieve the hardware
 188  * timestamp when it reads the packet out of the hardware. However in a DSA
 189  * switch, the DSA driver owning the interface to which the packet is
 190  * delivered is never notified unless we do so here.
 191  */
 192 static bool dsa_skb_defer_rx_timestamp(struct dsa_slave_priv *p,
 193                                        struct sk_buff *skb)
 194 {
 195         struct dsa_switch *ds = p->dp->ds;
 196         unsigned int type;
 197
 198         if (skb_headroom(skb) < ETH_HLEN)
 199                 return false;
 200
 201         __skb_push(skb, ETH_HLEN);
 202
 203         type = ptp_classify_raw(skb);
 204
 205         __skb_pull(skb, ETH_HLEN);
 206
 207         if (type == PTP_CLASS_NONE)
 208                 return false;
 209
 210         if (likely(ds->ops->port_rxtstamp))
 211                 return ds->ops->port_rxtstamp(ds, p->dp->index, skb, type);
 212
 213         return false;
 214 }
 215
 216 static int dsa_switch_rcv(struct sk_buff *skb, struct net_device *dev,
 217                           struct packet_type *pt, struct net_device *unused)
 218 {
 219         struct dsa_port *cpu_dp = dev->dsa_ptr;
 220         struct sk_buff *nskb = NULL;
 221         struct dsa_slave_priv *p;
 222
 223         if (unlikely(!cpu_dp)) {
 224                 kfree_skb(skb);
 225                 return 0;
 226         }
 227
 228         skb = skb_unshare(skb, GFP_ATOMIC);
 229         if (!skb)
 230                 return 0;
 231
 232         nskb = cpu_dp->rcv(skb, dev);
 233         if (!nskb) {
 234                 kfree_skb(skb);
 235                 return 0;
 236         }
 237
 238         skb = nskb;
 239         skb_push(skb, ETH_HLEN);
 240         skb->pkt_type = PACKET_HOST;
 241         skb->protocol = eth_type_trans(skb, skb->dev);
 242
 243         if (unlikely(!dsa_slave_dev_check(skb->dev))) {
 244                 /* Packet is to be injected directly on an upper
 245                  * device, e.g. a team/bond, so skip all DSA-port
 246                  * specific actions.
 247                  */
 248                 netif_rx(skb);
 249                 return 0;
 250         }
 251
 252         p = netdev_priv(skb->dev);
 253
 254         if (unlikely(cpu_dp->ds->untag_bridge_pvid)) {
 255                 nskb = dsa_untag_bridge_pvid(skb);
 256                 if (!nskb) {
 257                         kfree_skb(skb);
 258                         return 0;
 259                 }
 260                 skb = nskb;
 261         }
 262
 263         dev_sw_netstats_rx_add(skb->dev, skb->len);
 264
 265         if (dsa_skb_defer_rx_timestamp(p, skb))
 266                 return 0;
 267
 268         gro_cells_receive(&p->gcells, skb);
 269
 270         return 0;
 271 }
 272
 273 #ifdef CONFIG_PM_SLEEP
 274 static bool dsa_port_is_initialized(const struct dsa_port *dp)
 275 {
 276         return dp->type == DSA_PORT_TYPE_USER && dp->slave;
 277 }
 278
 279 int dsa_switch_suspend(struct dsa_switch *ds)
 280 {
 281         struct dsa_port *dp;
 282         int ret = 0;
 283
 284         /* Suspend slave network devices */
 285         dsa_switch_for_each_port(dp, ds) {
 286                 if (!dsa_port_is_initialized(dp))
 287                         continue;
 288
 289                 ret = dsa_slave_suspend(dp->slave);
 290                 if (ret)
 291                         return ret;
 292         }
 293
 294         if (ds->ops->suspend)
 295                 ret = ds->ops->suspend(ds);
 296
 297         return ret;
 298 }
 299 EXPORT_SYMBOL_GPL(dsa_switch_suspend);
 300
 301 int dsa_switch_resume(struct dsa_switch *ds)
 302 {
 303         struct dsa_port *dp;
 304         int ret = 0;
 305
 306         if (ds->ops->resume)
 307                 ret = ds->ops->resume(ds);
 308
 309         if (ret)
 310                 return ret;
 311
 312         /* Resume slave network devices */
 313         dsa_switch_for_each_port(dp, ds) {
 314                 if (!dsa_port_is_initialized(dp))
 315                         continue;
 316
 317                 ret = dsa_slave_resume(dp->slave);
 318                 if (ret)
 319                         return ret;
 320         }
 321
 322         return 0;
 323 }
 324 EXPORT_SYMBOL_GPL(dsa_switch_resume);
 325 #endif
 326
 327 static struct packet_type dsa_pack_type __read_mostly = {
 328         .type   = cpu_to_be16(ETH_P_XDSA),
 329         .func   = dsa_switch_rcv,
 330 };
 331
 332 static struct workqueue_struct *dsa_owq;
 333
 334 bool dsa_schedule_work(struct work_struct *work)
 335 {
 336         return queue_work(dsa_owq, work);
 337 }
 338
 339 void dsa_flush_workqueue(void)
 340 {
 341         flush_workqueue(dsa_owq);
 342 }
 343 EXPORT_SYMBOL_GPL(dsa_flush_workqueue);
 344
 345 int dsa_devlink_param_get(struct devlink *dl, u32 id,
 346                           struct devlink_param_gset_ctx *ctx)
 347 {
 348         struct dsa_switch *ds = dsa_devlink_to_ds(dl);
 349
 350         if (!ds->ops->devlink_param_get)
 351                 return -EOPNOTSUPP;
 352
 353         return ds->ops->devlink_param_get(ds, id, ctx);
 354 }
 355 EXPORT_SYMBOL_GPL(dsa_devlink_param_get);
 356
 357 int dsa_devlink_param_set(struct devlink *dl, u32 id,
 358                           struct devlink_param_gset_ctx *ctx)
 359 {
 360         struct dsa_switch *ds = dsa_devlink_to_ds(dl);
 361
 362         if (!ds->ops->devlink_param_set)
 363                 return -EOPNOTSUPP;
 364
 365         return ds->ops->devlink_param_set(ds, id, ctx);
 366 }
 367 EXPORT_SYMBOL_GPL(dsa_devlink_param_set);
 368
 369 int dsa_devlink_params_register(struct dsa_switch *ds,
 370                                 const struct devlink_param *params,
 371                                 size_t params_count)
 372 {
 373         return devlink_params_register(ds->devlink, params, params_count);
 374 }
 375 EXPORT_SYMBOL_GPL(dsa_devlink_params_register);
 376
 377 void dsa_devlink_params_unregister(struct dsa_switch *ds,
 378                                    const struct devlink_param *params,
 379                                    size_t params_count)
 380 {
 381         devlink_params_unregister(ds->devlink, params, params_count);
 382 }
 383 EXPORT_SYMBOL_GPL(dsa_devlink_params_unregister);
 384
 385 int dsa_devlink_resource_register(struct dsa_switch *ds,
 386                                   const char *resource_name,
 387                                   u64 resource_size,
 388                                   u64 resource_id,
 389                                   u64 parent_resource_id,
 390                                   const struct devlink_resource_size_params *size_params)
 391 {
 392         return devlink_resource_register(ds->devlink, resource_name,
 393                                          resource_size, resource_id,
 394                                          parent_resource_id,
 395                                          size_params);
 396 }
 397 EXPORT_SYMBOL_GPL(dsa_devlink_resource_register);
 398
 399 void dsa_devlink_resources_unregister(struct dsa_switch *ds)
 400 {
 401         devlink_resources_unregister(ds->devlink);
 402 }
 403 EXPORT_SYMBOL_GPL(dsa_devlink_resources_unregister);
 404
 405 void dsa_devlink_resource_occ_get_register(struct dsa_switch *ds,
 406                                            u64 resource_id,
 407                                            devlink_resource_occ_get_t *occ_get,
 408                                            void *occ_get_priv)
 409 {
 410         return devlink_resource_occ_get_register(ds->devlink, resource_id,
 411                                                  occ_get, occ_get_priv);
 412 }
 413 EXPORT_SYMBOL_GPL(dsa_devlink_resource_occ_get_register);
 414
 415 void dsa_devlink_resource_occ_get_unregister(struct dsa_switch *ds,
 416                                              u64 resource_id)
 417 {
 418         devlink_resource_occ_get_unregister(ds->devlink, resource_id);
 419 }
 420 EXPORT_SYMBOL_GPL(dsa_devlink_resource_occ_get_unregister);
 421
 422 struct devlink_region *
 423 dsa_devlink_region_create(struct dsa_switch *ds,
 424                           const struct devlink_region_ops *ops,
 425                           u32 region_max_snapshots, u64 region_size)
 426 {
 427         return devlink_region_create(ds->devlink, ops, region_max_snapshots,
 428                                      region_size);
 429 }
 430 EXPORT_SYMBOL_GPL(dsa_devlink_region_create);
 431
 432 struct devlink_region *
 433 dsa_devlink_port_region_create(struct dsa_switch *ds,
 434                                int port,
 435                                const struct devlink_port_region_ops *ops,
 436                                u32 region_max_snapshots, u64 region_size)
 437 {
 438         struct dsa_port *dp = dsa_to_port(ds, port);
 439
 440         return devlink_port_region_create(&dp->devlink_port, ops,
 441                                           region_max_snapshots,
 442                                           region_size);
 443 }
 444 EXPORT_SYMBOL_GPL(dsa_devlink_port_region_create);
 445
 446 void dsa_devlink_region_destroy(struct devlink_region *region)
 447 {
 448         devlink_region_destroy(region);
 449 }
 450 EXPORT_SYMBOL_GPL(dsa_devlink_region_destroy);
 451
 452 struct dsa_port *dsa_port_from_netdev(struct net_device *netdev)
 453 {
 454         if (!netdev || !dsa_slave_dev_check(netdev))
 455                 return ERR_PTR(-ENODEV);
 456
 457         return dsa_slave_to_port(netdev);
 458 }
 459 EXPORT_SYMBOL_GPL(dsa_port_from_netdev);
 460
 461 bool dsa_db_equal(const struct dsa_db *a, const struct dsa_db *b)
 462 {
 463         if (a->type != b->type)
 464                 return false;
 465
 466         switch (a->type) {
 467         case DSA_DB_PORT:
 468                 return a->dp == b->dp;
 469         case DSA_DB_LAG:
 470                 return a->lag.dev == b->lag.dev;
 471         case DSA_DB_BRIDGE:
 472                 return a->bridge.num == b->bridge.num;
 473         default:
 474                 WARN_ON(1);
 475                 return false;
 476         }
 477 }
 478
 479 bool dsa_fdb_present_in_other_db(struct dsa_switch *ds, int port,
 480                                  const unsigned char *addr, u16 vid,
 481                                  struct dsa_db db)
 482 {
 483         struct dsa_port *dp = dsa_to_port(ds, port);
 484         struct dsa_mac_addr *a;
 485
 486         lockdep_assert_held(&dp->addr_lists_lock);
 487
 488         list_for_each_entry(a, &dp->fdbs, list) {
 489                 if (!ether_addr_equal(a->addr, addr) || a->vid != vid)
 490                         continue;
 491
 492                 if (a->db.type == db.type && !dsa_db_equal(&a->db, &db))
 493                         return true;
 494         }
 495
 496         return false;
 497 }
 498 EXPORT_SYMBOL_GPL(dsa_fdb_present_in_other_db);
 499
 500 bool dsa_mdb_present_in_other_db(struct dsa_switch *ds, int port,
 501                                  const struct switchdev_obj_port_mdb *mdb,
 502                                  struct dsa_db db)
 503 {
 504         struct dsa_port *dp = dsa_to_port(ds, port);
 505         struct dsa_mac_addr *a;
 506
 507         lockdep_assert_held(&dp->addr_lists_lock);
 508
 509         list_for_each_entry(a, &dp->mdbs, list) {
 510                 if (!ether_addr_equal(a->addr, mdb->addr) || a->vid != mdb->vid)
 511                         continue;
 512
 513                 if (a->db.type == db.type && !dsa_db_equal(&a->db, &db))
 514                         return true;
 515         }
 516
 517         return false;
 518 }
 519 EXPORT_SYMBOL_GPL(dsa_mdb_present_in_other_db);
 520
 521 static int __init dsa_init_module(void)
 522 {
 523         int rc;
 524
 525         dsa_owq = alloc_ordered_workqueue("dsa_ordered",
 526                                           WQ_MEM_RECLAIM);
 527         if (!dsa_owq)
 528                 return -ENOMEM;
 529
 530         rc = dsa_slave_register_notifier();
 531         if (rc)
 532                 goto register_notifier_fail;
 533
 534         dev_add_pack(&dsa_pack_type);
 535
 536         dsa_tag_driver_register(&DSA_TAG_DRIVER_NAME(none_ops),
 537                                 THIS_MODULE);
 538
 539         return 0;
 540
 541 register_notifier_fail:
 542         destroy_workqueue(dsa_owq);
 543
 544         return rc;
 545 }
 546 module_init(dsa_init_module);
 547
 548 static void __exit dsa_cleanup_module(void)
 549 {
 550         dsa_tag_driver_unregister(&DSA_TAG_DRIVER_NAME(none_ops));
 551
 552         dsa_slave_unregister_notifier();
 553         dev_remove_pack(&dsa_pack_type);
 554         destroy_workqueue(dsa_owq);
 555 }
 556 module_exit(dsa_cleanup_module);
 557
 558 MODULE_AUTHOR("Lennert Buytenhek <buytenh@wantstofly.org>");
 559 MODULE_DESCRIPTION("Driver for Distributed Switch Architecture switch chips");
 560 MODULE_LICENSE("GPL");
 561 MODULE_ALIAS("platform:dsa");