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