net/hsr/hsr_device.c

   1 // SPDX-License-Identifier: GPL-2.0
   2 /* Copyright 2011-2014 Autronica Fire and Security AS
   3  *
   4  * Author(s):
   5  *      2011-2014 Arvid Brodin, arvid.brodin@alten.se
   6  * This file contains device methods for creating, using and destroying
   7  * virtual HSR or PRP devices.
   8  */
   9
  10 #include <linux/netdevice.h>
  11 #include <linux/skbuff.h>
  12 #include <linux/etherdevice.h>
  13 #include <linux/rtnetlink.h>
  14 #include <linux/pkt_sched.h>
  15 #include "hsr_device.h"
  16 #include "hsr_slave.h"
  17 #include "hsr_framereg.h"
  18 #include "hsr_main.h"
  19 #include "hsr_forward.h"
  20
  21 static bool is_admin_up(struct net_device *dev)
  22 {
  23         return dev && (dev->flags & IFF_UP);
  24 }
  25
  26 static bool is_slave_up(struct net_device *dev)
  27 {
  28         return dev && is_admin_up(dev) && netif_oper_up(dev);
  29 }
  30
  31 static void __hsr_set_operstate(struct net_device *dev, int transition)
  32 {
  33         write_lock_bh(&dev_base_lock);
  34         if (dev->operstate != transition) {
  35                 dev->operstate = transition;
  36                 write_unlock_bh(&dev_base_lock);
  37                 netdev_state_change(dev);
  38         } else {
  39                 write_unlock_bh(&dev_base_lock);
  40         }
  41 }
  42
  43 static void hsr_set_operstate(struct hsr_port *master, bool has_carrier)
  44 {
  45         if (!is_admin_up(master->dev)) {
  46                 __hsr_set_operstate(master->dev, IF_OPER_DOWN);
  47                 return;
  48         }
  49
  50         if (has_carrier)
  51                 __hsr_set_operstate(master->dev, IF_OPER_UP);
  52         else
  53                 __hsr_set_operstate(master->dev, IF_OPER_LOWERLAYERDOWN);
  54 }
  55
  56 static bool hsr_check_carrier(struct hsr_port *master)
  57 {
  58         struct hsr_port *port;
  59
  60         ASSERT_RTNL();
  61
  62         hsr_for_each_port(master->hsr, port) {
  63                 if (port->type != HSR_PT_MASTER && is_slave_up(port->dev)) {
  64                         netif_carrier_on(master->dev);
  65                         return true;
  66                 }
  67         }
  68
  69         netif_carrier_off(master->dev);
  70
  71         return false;
  72 }
  73
  74 static void hsr_check_announce(struct net_device *hsr_dev,
  75                                unsigned char old_operstate)
  76 {
  77         struct hsr_priv *hsr;
  78
  79         hsr = netdev_priv(hsr_dev);
  80
  81         if (hsr_dev->operstate == IF_OPER_UP && old_operstate != IF_OPER_UP) {
  82                 /* Went up */
  83                 hsr->announce_count = 0;
  84                 mod_timer(&hsr->announce_timer,
  85                           jiffies + msecs_to_jiffies(HSR_ANNOUNCE_INTERVAL));
  86         }
  87
  88         if (hsr_dev->operstate != IF_OPER_UP && old_operstate == IF_OPER_UP)
  89                 /* Went down */
  90                 del_timer(&hsr->announce_timer);
  91 }
  92
  93 void hsr_check_carrier_and_operstate(struct hsr_priv *hsr)
  94 {
  95         struct hsr_port *master;
  96         unsigned char old_operstate;
  97         bool has_carrier;
  98
  99         master = hsr_port_get_hsr(hsr, HSR_PT_MASTER);
 100         /* netif_stacked_transfer_operstate() cannot be used here since
 101          * it doesn't set IF_OPER_LOWERLAYERDOWN (?)
 102          */
 103         old_operstate = master->dev->operstate;
 104         has_carrier = hsr_check_carrier(master);
 105         hsr_set_operstate(master, has_carrier);
 106         hsr_check_announce(master->dev, old_operstate);
 107 }
 108
 109 int hsr_get_max_mtu(struct hsr_priv *hsr)
 110 {
 111         unsigned int mtu_max;
 112         struct hsr_port *port;
 113
 114         mtu_max = ETH_DATA_LEN;
 115         hsr_for_each_port(hsr, port)
 116                 if (port->type != HSR_PT_MASTER)
 117                         mtu_max = min(port->dev->mtu, mtu_max);
 118
 119         if (mtu_max < HSR_HLEN)
 120                 return 0;
 121         return mtu_max - HSR_HLEN;
 122 }
 123
 124 static int hsr_dev_change_mtu(struct net_device *dev, int new_mtu)
 125 {
 126         struct hsr_priv *hsr;
 127
 128         hsr = netdev_priv(dev);
 129
 130         if (new_mtu > hsr_get_max_mtu(hsr)) {
 131                 netdev_info(dev, "A HSR master's MTU cannot be greater than the smallest MTU of its slaves minus the HSR Tag length (%d octets).\n",
 132                             HSR_HLEN);
 133                 return -EINVAL;
 134         }
 135
 136         dev->mtu = new_mtu;
 137
 138         return 0;
 139 }
 140
 141 static int hsr_dev_open(struct net_device *dev)
 142 {
 143         struct hsr_priv *hsr;
 144         struct hsr_port *port;
 145         char designation;
 146
 147         hsr = netdev_priv(dev);
 148         designation = '\0';
 149
 150         hsr_for_each_port(hsr, port) {
 151                 if (port->type == HSR_PT_MASTER)
 152                         continue;
 153                 switch (port->type) {
 154                 case HSR_PT_SLAVE_A:
 155                         designation = 'A';
 156                         break;
 157                 case HSR_PT_SLAVE_B:
 158                         designation = 'B';
 159                         break;
 160                 default:
 161                         designation = '?';
 162                 }
 163                 if (!is_slave_up(port->dev))
 164                         netdev_warn(dev, "Slave %c (%s) is not up; please bring it up to get a fully working HSR network\n",
 165                                     designation, port->dev->name);
 166         }
 167
 168         if (designation == '\0')
 169                 netdev_warn(dev, "No slave devices configured\n");
 170
 171         return 0;
 172 }
 173
 174 static int hsr_dev_close(struct net_device *dev)
 175 {
 176         /* Nothing to do here. */
 177         return 0;
 178 }
 179
 180 static netdev_features_t hsr_features_recompute(struct hsr_priv *hsr,
 181                                                 netdev_features_t features)
 182 {
 183         netdev_features_t mask;
 184         struct hsr_port *port;
 185
 186         mask = features;
 187
 188         /* Mask out all features that, if supported by one device, should be
 189          * enabled for all devices (see NETIF_F_ONE_FOR_ALL).
 190          *
 191          * Anything that's off in mask will not be enabled - so only things
 192          * that were in features originally, and also is in NETIF_F_ONE_FOR_ALL,
 193          * may become enabled.
 194          */
 195         features &= ~NETIF_F_ONE_FOR_ALL;
 196         hsr_for_each_port(hsr, port)
 197                 features = netdev_increment_features(features,
 198                                                      port->dev->features,
 199                                                      mask);
 200
 201         return features;
 202 }
 203
 204 static netdev_features_t hsr_fix_features(struct net_device *dev,
 205                                           netdev_features_t features)
 206 {
 207         struct hsr_priv *hsr = netdev_priv(dev);
 208
 209         return hsr_features_recompute(hsr, features);
 210 }
 211
 212 static netdev_tx_t hsr_dev_xmit(struct sk_buff *skb, struct net_device *dev)
 213 {
 214         struct hsr_priv *hsr = netdev_priv(dev);
 215         struct hsr_port *master;
 216
 217         master = hsr_port_get_hsr(hsr, HSR_PT_MASTER);
 218         if (master) {
 219                 skb->dev = master->dev;
 220                 hsr_forward_skb(skb, master);
 221         } else {
 222                 atomic_long_inc(&dev->tx_dropped);
 223                 dev_kfree_skb_any(skb);
 224         }
 225         return NETDEV_TX_OK;
 226 }
 227
 228 static const struct header_ops hsr_header_ops = {
 229         .create  = eth_header,
 230         .parse   = eth_header_parse,
 231 };
 232
 233 static struct sk_buff *hsr_init_skb(struct hsr_port *master, u16 proto)
 234 {
 235         struct hsr_priv *hsr = master->hsr;
 236         struct sk_buff *skb;
 237         int hlen, tlen;
 238
 239         hlen = LL_RESERVED_SPACE(master->dev);
 240         tlen = master->dev->needed_tailroom;
 241         /* skb size is same for PRP/HSR frames, only difference
 242          * being, for PRP it is a trailer and for HSR it is a
 243          * header
 244          */
 245         skb = dev_alloc_skb(sizeof(struct hsr_tag) +
 246                             sizeof(struct hsr_sup_tag) +
 247                             sizeof(struct hsr_sup_payload) + hlen + tlen);
 248
 249         if (!skb)
 250                 return skb;
 251
 252         skb_reserve(skb, hlen);
 253         skb->dev = master->dev;
 254         skb->protocol = htons(proto);
 255         skb->priority = TC_PRIO_CONTROL;
 256
 257         if (dev_hard_header(skb, skb->dev, proto,
 258                             hsr->sup_multicast_addr,
 259                             skb->dev->dev_addr, skb->len) <= 0)
 260                 goto out;
 261
 262         skb_reset_mac_header(skb);
 263         skb_reset_network_header(skb);
 264         skb_reset_transport_header(skb);
 265
 266         return skb;
 267 out:
 268         kfree_skb(skb);
 269
 270         return NULL;
 271 }
 272
 273 static void send_hsr_supervision_frame(struct hsr_port *master,
 274                                        unsigned long *interval)
 275 {
 276         struct hsr_priv *hsr = master->hsr;
 277         __u8 type = HSR_TLV_LIFE_CHECK;
 278         struct hsr_tag *hsr_tag = NULL;
 279         struct hsr_sup_payload *hsr_sp;
 280         struct hsr_sup_tag *hsr_stag;
 281         unsigned long irqflags;
 282         struct sk_buff *skb;
 283         u16 proto;
 284
 285         *interval = msecs_to_jiffies(HSR_LIFE_CHECK_INTERVAL);
 286         if (hsr->announce_count < 3 && hsr->prot_version == 0) {
 287                 type = HSR_TLV_ANNOUNCE;
 288                 *interval = msecs_to_jiffies(HSR_ANNOUNCE_INTERVAL);
 289                 hsr->announce_count++;
 290         }
 291
 292         if (!hsr->prot_version)
 293                 proto = ETH_P_PRP;
 294         else
 295                 proto = ETH_P_HSR;
 296
 297         skb = hsr_init_skb(master, proto);
 298         if (!skb) {
 299                 WARN_ONCE(1, "HSR: Could not send supervision frame\n");
 300                 return;
 301         }
 302
 303         if (hsr->prot_version > 0) {
 304                 hsr_tag = skb_put(skb, sizeof(struct hsr_tag));
 305                 hsr_tag->encap_proto = htons(ETH_P_PRP);
 306                 set_hsr_tag_LSDU_size(hsr_tag, HSR_V1_SUP_LSDUSIZE);
 307         }
 308
 309         hsr_stag = skb_put(skb, sizeof(struct hsr_sup_tag));
 310         set_hsr_stag_path(hsr_stag, (hsr->prot_version ? 0x0 : 0xf));
 311         set_hsr_stag_HSR_ver(hsr_stag, hsr->prot_version);
 312
 313         /* From HSRv1 on we have separate supervision sequence numbers. */
 314         spin_lock_irqsave(&master->hsr->seqnr_lock, irqflags);
 315         if (hsr->prot_version > 0) {
 316                 hsr_stag->sequence_nr = htons(hsr->sup_sequence_nr);
 317                 hsr->sup_sequence_nr++;
 318                 hsr_tag->sequence_nr = htons(hsr->sequence_nr);
 319                 hsr->sequence_nr++;
 320         } else {
 321                 hsr_stag->sequence_nr = htons(hsr->sequence_nr);
 322                 hsr->sequence_nr++;
 323         }
 324         spin_unlock_irqrestore(&master->hsr->seqnr_lock, irqflags);
 325
 326         hsr_stag->HSR_TLV_type = type;
 327         /* TODO: Why 12 in HSRv0? */
 328         hsr_stag->HSR_TLV_length = hsr->prot_version ?
 329                                 sizeof(struct hsr_sup_payload) : 12;
 330
 331         /* Payload: MacAddressA */
 332         hsr_sp = skb_put(skb, sizeof(struct hsr_sup_payload));
 333         ether_addr_copy(hsr_sp->macaddress_A, master->dev->dev_addr);
 334
 335         if (skb_put_padto(skb, ETH_ZLEN + HSR_HLEN))
 336                 return;
 337
 338         hsr_forward_skb(skb, master);
 339
 340         return;
 341 }
 342
 343 static void send_prp_supervision_frame(struct hsr_port *master,
 344                                        unsigned long *interval)
 345 {
 346         struct hsr_priv *hsr = master->hsr;
 347         struct hsr_sup_payload *hsr_sp;
 348         struct hsr_sup_tag *hsr_stag;
 349         unsigned long irqflags;
 350         struct sk_buff *skb;
 351         struct prp_rct *rct;
 352         u8 *tail;
 353
 354         skb = hsr_init_skb(master, ETH_P_PRP);
 355         if (!skb) {
 356                 WARN_ONCE(1, "PRP: Could not send supervision frame\n");
 357                 return;
 358         }
 359
 360         *interval = msecs_to_jiffies(HSR_LIFE_CHECK_INTERVAL);
 361         hsr_stag = skb_put(skb, sizeof(struct hsr_sup_tag));
 362         set_hsr_stag_path(hsr_stag, (hsr->prot_version ? 0x0 : 0xf));
 363         set_hsr_stag_HSR_ver(hsr_stag, (hsr->prot_version ? 1 : 0));
 364
 365         /* From HSRv1 on we have separate supervision sequence numbers. */
 366         spin_lock_irqsave(&master->hsr->seqnr_lock, irqflags);
 367         hsr_stag->sequence_nr = htons(hsr->sup_sequence_nr);
 368         hsr->sup_sequence_nr++;
 369         hsr_stag->HSR_TLV_type = PRP_TLV_LIFE_CHECK_DD;
 370         hsr_stag->HSR_TLV_length = sizeof(struct hsr_sup_payload);
 371
 372         /* Payload: MacAddressA */
 373         hsr_sp = skb_put(skb, sizeof(struct hsr_sup_payload));
 374         ether_addr_copy(hsr_sp->macaddress_A, master->dev->dev_addr);
 375
 376         if (skb_put_padto(skb, ETH_ZLEN + HSR_HLEN)) {
 377                 spin_unlock_irqrestore(&master->hsr->seqnr_lock, irqflags);
 378                 return;
 379         }
 380
 381         tail = skb_tail_pointer(skb) - HSR_HLEN;
 382         rct = (struct prp_rct *)tail;
 383         rct->PRP_suffix = htons(ETH_P_PRP);
 384         set_prp_LSDU_size(rct, HSR_V1_SUP_LSDUSIZE);
 385         rct->sequence_nr = htons(hsr->sequence_nr);
 386         hsr->sequence_nr++;
 387         spin_unlock_irqrestore(&master->hsr->seqnr_lock, irqflags);
 388
 389         hsr_forward_skb(skb, master);
 390 }
 391
 392 /* Announce (supervision frame) timer function
 393  */
 394 static void hsr_announce(struct timer_list *t)
 395 {
 396         struct hsr_priv *hsr;
 397         struct hsr_port *master;
 398         unsigned long interval;
 399
 400         hsr = from_timer(hsr, t, announce_timer);
 401
 402         rcu_read_lock();
 403         master = hsr_port_get_hsr(hsr, HSR_PT_MASTER);
 404         hsr->proto_ops->send_sv_frame(master, &interval);
 405
 406         if (is_admin_up(master->dev))
 407                 mod_timer(&hsr->announce_timer, jiffies + interval);
 408
 409         rcu_read_unlock();
 410 }
 411
 412 void hsr_del_ports(struct hsr_priv *hsr)
 413 {
 414         struct hsr_port *port;
 415
 416         port = hsr_port_get_hsr(hsr, HSR_PT_SLAVE_A);
 417         if (port)
 418                 hsr_del_port(port);
 419
 420         port = hsr_port_get_hsr(hsr, HSR_PT_SLAVE_B);
 421         if (port)
 422                 hsr_del_port(port);
 423
 424         port = hsr_port_get_hsr(hsr, HSR_PT_MASTER);
 425         if (port)
 426                 hsr_del_port(port);
 427 }
 428
 429 static const struct net_device_ops hsr_device_ops = {
 430         .ndo_change_mtu = hsr_dev_change_mtu,
 431         .ndo_open = hsr_dev_open,
 432         .ndo_stop = hsr_dev_close,
 433         .ndo_start_xmit = hsr_dev_xmit,
 434         .ndo_fix_features = hsr_fix_features,
 435 };
 436
 437 static struct device_type hsr_type = {
 438         .name = "hsr",
 439 };
 440
 441 static struct hsr_proto_ops hsr_ops = {
 442         .send_sv_frame = send_hsr_supervision_frame,
 443 };
 444
 445 struct hsr_proto_ops prp_ops = {
 446         .send_sv_frame = send_prp_supervision_frame,
 447 };
 448
 449 void hsr_dev_setup(struct net_device *dev)
 450 {
 451         eth_hw_addr_random(dev);
 452
 453         ether_setup(dev);
 454         dev->min_mtu = 0;
 455         dev->header_ops = &hsr_header_ops;
 456         dev->netdev_ops = &hsr_device_ops;
 457         SET_NETDEV_DEVTYPE(dev, &hsr_type);
 458         dev->priv_flags |= IFF_NO_QUEUE;
 459
 460         dev->needs_free_netdev = true;
 461
 462         dev->hw_features = NETIF_F_SG | NETIF_F_FRAGLIST | NETIF_F_HIGHDMA |
 463                            NETIF_F_GSO_MASK | NETIF_F_HW_CSUM |
 464                            NETIF_F_HW_VLAN_CTAG_TX;
 465
 466         dev->features = dev->hw_features;
 467
 468         /* Prevent recursive tx locking */
 469         dev->features |= NETIF_F_LLTX;
 470         /* VLAN on top of HSR needs testing and probably some work on
 471          * hsr_header_create() etc.
 472          */
 473         dev->features |= NETIF_F_VLAN_CHALLENGED;
 474         /* Not sure about this. Taken from bridge code. netdev_features.h says
 475          * it means "Does not change network namespaces".
 476          */
 477         dev->features |= NETIF_F_NETNS_LOCAL;
 478 }
 479
 480 /* Return true if dev is a HSR master; return false otherwise.
 481  */
 482 inline bool is_hsr_master(struct net_device *dev)
 483 {
 484         return (dev->netdev_ops->ndo_start_xmit == hsr_dev_xmit);
 485 }
 486
 487 /* Default multicast address for HSR Supervision frames */
 488 static const unsigned char def_multicast_addr[ETH_ALEN] __aligned(2) = {
 489         0x01, 0x15, 0x4e, 0x00, 0x01, 0x00
 490 };
 491
 492 int hsr_dev_finalize(struct net_device *hsr_dev, struct net_device *slave[2],
 493                      unsigned char multicast_spec, u8 protocol_version,
 494                      struct netlink_ext_ack *extack)
 495 {
 496         bool unregister = false;
 497         struct hsr_priv *hsr;
 498         int res;
 499
 500         hsr = netdev_priv(hsr_dev);
 501         INIT_LIST_HEAD(&hsr->ports);
 502         INIT_LIST_HEAD(&hsr->node_db);
 503         INIT_LIST_HEAD(&hsr->self_node_db);
 504         spin_lock_init(&hsr->list_lock);
 505
 506         ether_addr_copy(hsr_dev->dev_addr, slave[0]->dev_addr);
 507
 508         /* currently PRP is not supported */
 509         if (protocol_version == PRP_V1)
 510                 return -EPROTONOSUPPORT;
 511
 512         /* initialize protocol specific functions */
 513         if (protocol_version == PRP_V1)
 514                 hsr->proto_ops = &prp_ops;
 515         else
 516                 hsr->proto_ops = &hsr_ops;
 517
 518         /* Make sure we recognize frames from ourselves in hsr_rcv() */
 519         res = hsr_create_self_node(hsr, hsr_dev->dev_addr,
 520                                    slave[1]->dev_addr);
 521         if (res < 0)
 522                 return res;
 523
 524         spin_lock_init(&hsr->seqnr_lock);
 525         /* Overflow soon to find bugs easier: */
 526         hsr->sequence_nr = HSR_SEQNR_START;
 527         hsr->sup_sequence_nr = HSR_SUP_SEQNR_START;
 528
 529         timer_setup(&hsr->announce_timer, hsr_announce, 0);
 530         timer_setup(&hsr->prune_timer, hsr_prune_nodes, 0);
 531
 532         ether_addr_copy(hsr->sup_multicast_addr, def_multicast_addr);
 533         hsr->sup_multicast_addr[ETH_ALEN - 1] = multicast_spec;
 534
 535         hsr->prot_version = protocol_version;
 536
 537         /* FIXME: should I modify the value of these?
 538          *
 539          * - hsr_dev->flags - i.e.
 540          *                      IFF_MASTER/SLAVE?
 541          * - hsr_dev->priv_flags - i.e.
 542          *                      IFF_EBRIDGE?
 543          *                      IFF_TX_SKB_SHARING?
 544          *                      IFF_HSR_MASTER/SLAVE?
 545          */
 546
 547         /* Make sure the 1st call to netif_carrier_on() gets through */
 548         netif_carrier_off(hsr_dev);
 549
 550         res = hsr_add_port(hsr, hsr_dev, HSR_PT_MASTER, extack);
 551         if (res)
 552                 goto err_add_master;
 553
 554         res = register_netdevice(hsr_dev);
 555         if (res)
 556                 goto err_unregister;
 557
 558         unregister = true;
 559
 560         res = hsr_add_port(hsr, slave[0], HSR_PT_SLAVE_A, extack);
 561         if (res)
 562                 goto err_unregister;
 563
 564         res = hsr_add_port(hsr, slave[1], HSR_PT_SLAVE_B, extack);
 565         if (res)
 566                 goto err_unregister;
 567
 568         hsr_debugfs_init(hsr, hsr_dev);
 569         mod_timer(&hsr->prune_timer, jiffies + msecs_to_jiffies(PRUNE_PERIOD));
 570
 571         return 0;
 572
 573 err_unregister:
 574         hsr_del_ports(hsr);
 575 err_add_master:
 576         hsr_del_self_node(hsr);
 577
 578         if (unregister)
 579                 unregister_netdevice(hsr_dev);
 580         return res;
 581 }