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