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