1 // SPDX-License-Identifier: GPL-2.0-or-later 2 3 #include <linux/mrp_bridge.h> 4 #include "br_private_mrp.h" 5 6 static const u8 mrp_test_dmac[ETH_ALEN] = { 0x1, 0x15, 0x4e, 0x0, 0x0, 0x1 }; 7 8 static struct net_bridge_port *br_mrp_get_port(struct net_bridge *br, 9 u32 ifindex) 10 { 11 struct net_bridge_port *res = NULL; 12 struct net_bridge_port *port; 13 14 list_for_each_entry(port, &br->port_list, list) { 15 if (port->dev->ifindex == ifindex) { 16 res = port; 17 break; 18 } 19 } 20 21 return res; 22 } 23 24 static struct br_mrp *br_mrp_find_id(struct net_bridge *br, u32 ring_id) 25 { 26 struct br_mrp *res = NULL; 27 struct br_mrp *mrp; 28 29 list_for_each_entry_rcu(mrp, &br->mrp_list, list, 30 lockdep_rtnl_is_held()) { 31 if (mrp->ring_id == ring_id) { 32 res = mrp; 33 break; 34 } 35 } 36 37 return res; 38 } 39 40 static struct br_mrp *br_mrp_find_port(struct net_bridge *br, 41 struct net_bridge_port *p) 42 { 43 struct br_mrp *res = NULL; 44 struct br_mrp *mrp; 45 46 list_for_each_entry_rcu(mrp, &br->mrp_list, list, 47 lockdep_rtnl_is_held()) { 48 if (rcu_access_pointer(mrp->p_port) == p || 49 rcu_access_pointer(mrp->s_port) == p) { 50 res = mrp; 51 break; 52 } 53 } 54 55 return res; 56 } 57 58 static int br_mrp_next_seq(struct br_mrp *mrp) 59 { 60 mrp->seq_id++; 61 return mrp->seq_id; 62 } 63 64 static struct sk_buff *br_mrp_skb_alloc(struct net_bridge_port *p, 65 const u8 *src, const u8 *dst) 66 { 67 struct ethhdr *eth_hdr; 68 struct sk_buff *skb; 69 u16 *version; 70 71 skb = dev_alloc_skb(MRP_MAX_FRAME_LENGTH); 72 if (!skb) 73 return NULL; 74 75 skb->dev = p->dev; 76 skb->protocol = htons(ETH_P_MRP); 77 skb->priority = MRP_FRAME_PRIO; 78 skb_reserve(skb, sizeof(*eth_hdr)); 79 80 eth_hdr = skb_push(skb, sizeof(*eth_hdr)); 81 ether_addr_copy(eth_hdr->h_dest, dst); 82 ether_addr_copy(eth_hdr->h_source, src); 83 eth_hdr->h_proto = htons(ETH_P_MRP); 84 85 version = skb_put(skb, sizeof(*version)); 86 *version = cpu_to_be16(MRP_VERSION); 87 88 return skb; 89 } 90 91 static void br_mrp_skb_tlv(struct sk_buff *skb, 92 enum br_mrp_tlv_header_type type, 93 u8 length) 94 { 95 struct br_mrp_tlv_hdr *hdr; 96 97 hdr = skb_put(skb, sizeof(*hdr)); 98 hdr->type = type; 99 hdr->length = length; 100 } 101 102 static void br_mrp_skb_common(struct sk_buff *skb, struct br_mrp *mrp) 103 { 104 struct br_mrp_common_hdr *hdr; 105 106 br_mrp_skb_tlv(skb, BR_MRP_TLV_HEADER_COMMON, sizeof(*hdr)); 107 108 hdr = skb_put(skb, sizeof(*hdr)); 109 hdr->seq_id = cpu_to_be16(br_mrp_next_seq(mrp)); 110 memset(hdr->domain, 0xff, MRP_DOMAIN_UUID_LENGTH); 111 } 112 113 static struct sk_buff *br_mrp_alloc_test_skb(struct br_mrp *mrp, 114 struct net_bridge_port *p, 115 enum br_mrp_port_role_type port_role) 116 { 117 struct br_mrp_ring_test_hdr *hdr = NULL; 118 struct sk_buff *skb = NULL; 119 120 if (!p) 121 return NULL; 122 123 skb = br_mrp_skb_alloc(p, p->dev->dev_addr, mrp_test_dmac); 124 if (!skb) 125 return NULL; 126 127 br_mrp_skb_tlv(skb, BR_MRP_TLV_HEADER_RING_TEST, sizeof(*hdr)); 128 hdr = skb_put(skb, sizeof(*hdr)); 129 130 hdr->prio = cpu_to_be16(MRP_DEFAULT_PRIO); 131 ether_addr_copy(hdr->sa, p->br->dev->dev_addr); 132 hdr->port_role = cpu_to_be16(port_role); 133 hdr->state = cpu_to_be16(mrp->ring_state); 134 hdr->transitions = cpu_to_be16(mrp->ring_transitions); 135 hdr->timestamp = cpu_to_be32(jiffies_to_msecs(jiffies)); 136 137 br_mrp_skb_common(skb, mrp); 138 br_mrp_skb_tlv(skb, BR_MRP_TLV_HEADER_END, 0x0); 139 140 return skb; 141 } 142 143 static void br_mrp_test_work_expired(struct work_struct *work) 144 { 145 struct delayed_work *del_work = to_delayed_work(work); 146 struct br_mrp *mrp = container_of(del_work, struct br_mrp, test_work); 147 struct net_bridge_port *p; 148 bool notify_open = false; 149 struct sk_buff *skb; 150 151 if (time_before_eq(mrp->test_end, jiffies)) 152 return; 153 154 if (mrp->test_count_miss < mrp->test_max_miss) { 155 mrp->test_count_miss++; 156 } else { 157 /* Notify that the ring is open only if the ring state is 158 * closed, otherwise it would continue to notify at every 159 * interval. 160 */ 161 if (mrp->ring_state == BR_MRP_RING_STATE_CLOSED) 162 notify_open = true; 163 } 164 165 rcu_read_lock(); 166 167 p = rcu_dereference(mrp->p_port); 168 if (p) { 169 skb = br_mrp_alloc_test_skb(mrp, p, BR_MRP_PORT_ROLE_PRIMARY); 170 if (!skb) 171 goto out; 172 173 skb_reset_network_header(skb); 174 dev_queue_xmit(skb); 175 176 if (notify_open && !mrp->ring_role_offloaded) 177 br_mrp_port_open(p->dev, true); 178 } 179 180 p = rcu_dereference(mrp->s_port); 181 if (p) { 182 skb = br_mrp_alloc_test_skb(mrp, p, BR_MRP_PORT_ROLE_SECONDARY); 183 if (!skb) 184 goto out; 185 186 skb_reset_network_header(skb); 187 dev_queue_xmit(skb); 188 189 if (notify_open && !mrp->ring_role_offloaded) 190 br_mrp_port_open(p->dev, true); 191 } 192 193 out: 194 rcu_read_unlock(); 195 196 queue_delayed_work(system_wq, &mrp->test_work, 197 usecs_to_jiffies(mrp->test_interval)); 198 } 199 200 /* Deletes the MRP instance. 201 * note: called under rtnl_lock 202 */ 203 static void br_mrp_del_impl(struct net_bridge *br, struct br_mrp *mrp) 204 { 205 struct net_bridge_port *p; 206 207 /* Stop sending MRP_Test frames */ 208 cancel_delayed_work_sync(&mrp->test_work); 209 br_mrp_switchdev_send_ring_test(br, mrp, 0, 0, 0); 210 211 br_mrp_switchdev_del(br, mrp); 212 213 /* Reset the ports */ 214 p = rtnl_dereference(mrp->p_port); 215 if (p) { 216 spin_lock_bh(&br->lock); 217 p->state = BR_STATE_FORWARDING; 218 p->flags &= ~BR_MRP_AWARE; 219 spin_unlock_bh(&br->lock); 220 br_mrp_port_switchdev_set_state(p, BR_STATE_FORWARDING); 221 rcu_assign_pointer(mrp->p_port, NULL); 222 } 223 224 p = rtnl_dereference(mrp->s_port); 225 if (p) { 226 spin_lock_bh(&br->lock); 227 p->state = BR_STATE_FORWARDING; 228 p->flags &= ~BR_MRP_AWARE; 229 spin_unlock_bh(&br->lock); 230 br_mrp_port_switchdev_set_state(p, BR_STATE_FORWARDING); 231 rcu_assign_pointer(mrp->s_port, NULL); 232 } 233 234 list_del_rcu(&mrp->list); 235 kfree_rcu(mrp, rcu); 236 } 237 238 /* Adds a new MRP instance. 239 * note: called under rtnl_lock 240 */ 241 int br_mrp_add(struct net_bridge *br, struct br_mrp_instance *instance) 242 { 243 struct net_bridge_port *p; 244 struct br_mrp *mrp; 245 int err; 246 247 /* If the ring exists, it is not possible to create another one with the 248 * same ring_id 249 */ 250 mrp = br_mrp_find_id(br, instance->ring_id); 251 if (mrp) 252 return -EINVAL; 253 254 if (!br_mrp_get_port(br, instance->p_ifindex) || 255 !br_mrp_get_port(br, instance->s_ifindex)) 256 return -EINVAL; 257 258 mrp = kzalloc(sizeof(*mrp), GFP_KERNEL); 259 if (!mrp) 260 return -ENOMEM; 261 262 mrp->ring_id = instance->ring_id; 263 264 p = br_mrp_get_port(br, instance->p_ifindex); 265 spin_lock_bh(&br->lock); 266 p->state = BR_STATE_FORWARDING; 267 p->flags |= BR_MRP_AWARE; 268 spin_unlock_bh(&br->lock); 269 rcu_assign_pointer(mrp->p_port, p); 270 271 p = br_mrp_get_port(br, instance->s_ifindex); 272 spin_lock_bh(&br->lock); 273 p->state = BR_STATE_FORWARDING; 274 p->flags |= BR_MRP_AWARE; 275 spin_unlock_bh(&br->lock); 276 rcu_assign_pointer(mrp->s_port, p); 277 278 INIT_DELAYED_WORK(&mrp->test_work, br_mrp_test_work_expired); 279 list_add_tail_rcu(&mrp->list, &br->mrp_list); 280 281 err = br_mrp_switchdev_add(br, mrp); 282 if (err) 283 goto delete_mrp; 284 285 return 0; 286 287 delete_mrp: 288 br_mrp_del_impl(br, mrp); 289 290 return err; 291 } 292 293 /* Deletes the MRP instance from which the port is part of 294 * note: called under rtnl_lock 295 */ 296 void br_mrp_port_del(struct net_bridge *br, struct net_bridge_port *p) 297 { 298 struct br_mrp *mrp = br_mrp_find_port(br, p); 299 300 /* If the port is not part of a MRP instance just bail out */ 301 if (!mrp) 302 return; 303 304 br_mrp_del_impl(br, mrp); 305 } 306 307 /* Deletes existing MRP instance based on ring_id 308 * note: called under rtnl_lock 309 */ 310 int br_mrp_del(struct net_bridge *br, struct br_mrp_instance *instance) 311 { 312 struct br_mrp *mrp = br_mrp_find_id(br, instance->ring_id); 313 314 if (!mrp) 315 return -EINVAL; 316 317 br_mrp_del_impl(br, mrp); 318 319 return 0; 320 } 321 322 /* Set port state, port state can be forwarding, blocked or disabled 323 * note: already called with rtnl_lock 324 */ 325 int br_mrp_set_port_state(struct net_bridge_port *p, 326 enum br_mrp_port_state_type state) 327 { 328 if (!p || !(p->flags & BR_MRP_AWARE)) 329 return -EINVAL; 330 331 spin_lock_bh(&p->br->lock); 332 333 if (state == BR_MRP_PORT_STATE_FORWARDING) 334 p->state = BR_STATE_FORWARDING; 335 else 336 p->state = BR_STATE_BLOCKING; 337 338 spin_unlock_bh(&p->br->lock); 339 340 br_mrp_port_switchdev_set_state(p, state); 341 342 return 0; 343 } 344 345 /* Set port role, port role can be primary or secondary 346 * note: already called with rtnl_lock 347 */ 348 int br_mrp_set_port_role(struct net_bridge_port *p, 349 struct br_mrp_port_role *role) 350 { 351 struct br_mrp *mrp; 352 353 if (!p || !(p->flags & BR_MRP_AWARE)) 354 return -EINVAL; 355 356 mrp = br_mrp_find_id(p->br, role->ring_id); 357 358 if (!mrp) 359 return -EINVAL; 360 361 if (role->role == BR_MRP_PORT_ROLE_PRIMARY) 362 rcu_assign_pointer(mrp->p_port, p); 363 else 364 rcu_assign_pointer(mrp->s_port, p); 365 366 br_mrp_port_switchdev_set_role(p, role->role); 367 368 return 0; 369 } 370 371 /* Set ring state, ring state can be only Open or Closed 372 * note: already called with rtnl_lock 373 */ 374 int br_mrp_set_ring_state(struct net_bridge *br, 375 struct br_mrp_ring_state *state) 376 { 377 struct br_mrp *mrp = br_mrp_find_id(br, state->ring_id); 378 379 if (!mrp) 380 return -EINVAL; 381 382 if (mrp->ring_state == BR_MRP_RING_STATE_CLOSED && 383 state->ring_state != BR_MRP_RING_STATE_CLOSED) 384 mrp->ring_transitions++; 385 386 mrp->ring_state = state->ring_state; 387 388 br_mrp_switchdev_set_ring_state(br, mrp, state->ring_state); 389 390 return 0; 391 } 392 393 /* Set ring role, ring role can be only MRM(Media Redundancy Manager) or 394 * MRC(Media Redundancy Client). 395 * note: already called with rtnl_lock 396 */ 397 int br_mrp_set_ring_role(struct net_bridge *br, 398 struct br_mrp_ring_role *role) 399 { 400 struct br_mrp *mrp = br_mrp_find_id(br, role->ring_id); 401 int err; 402 403 if (!mrp) 404 return -EINVAL; 405 406 mrp->ring_role = role->ring_role; 407 408 /* If there is an error just bailed out */ 409 err = br_mrp_switchdev_set_ring_role(br, mrp, role->ring_role); 410 if (err && err != -EOPNOTSUPP) 411 return err; 412 413 /* Now detect if the HW actually applied the role or not. If the HW 414 * applied the role it means that the SW will not to do those operations 415 * anymore. For example if the role ir MRM then the HW will notify the 416 * SW when ring is open, but if the is not pushed to the HW the SW will 417 * need to detect when the ring is open 418 */ 419 mrp->ring_role_offloaded = err == -EOPNOTSUPP ? 0 : 1; 420 421 return 0; 422 } 423 424 /* Start to generate MRP test frames, the frames are generated by HW and if it 425 * fails, they are generated by the SW. 426 * note: already called with rtnl_lock 427 */ 428 int br_mrp_start_test(struct net_bridge *br, 429 struct br_mrp_start_test *test) 430 { 431 struct br_mrp *mrp = br_mrp_find_id(br, test->ring_id); 432 433 if (!mrp) 434 return -EINVAL; 435 436 /* Try to push it to the HW and if it fails then continue to generate in 437 * SW and if that also fails then return error 438 */ 439 if (!br_mrp_switchdev_send_ring_test(br, mrp, test->interval, 440 test->max_miss, test->period)) 441 return 0; 442 443 mrp->test_interval = test->interval; 444 mrp->test_end = jiffies + usecs_to_jiffies(test->period); 445 mrp->test_max_miss = test->max_miss; 446 mrp->test_count_miss = 0; 447 queue_delayed_work(system_wq, &mrp->test_work, 448 usecs_to_jiffies(test->interval)); 449 450 return 0; 451 } 452 453 /* Process only MRP Test frame. All the other MRP frames are processed by 454 * userspace application 455 * note: already called with rcu_read_lock 456 */ 457 static void br_mrp_mrm_process(struct br_mrp *mrp, struct net_bridge_port *port, 458 struct sk_buff *skb) 459 { 460 const struct br_mrp_tlv_hdr *hdr; 461 struct br_mrp_tlv_hdr _hdr; 462 463 /* Each MRP header starts with a version field which is 16 bits. 464 * Therefore skip the version and get directly the TLV header. 465 */ 466 hdr = skb_header_pointer(skb, sizeof(uint16_t), sizeof(_hdr), &_hdr); 467 if (!hdr) 468 return; 469 470 if (hdr->type != BR_MRP_TLV_HEADER_RING_TEST) 471 return; 472 473 mrp->test_count_miss = 0; 474 475 /* Notify the userspace that the ring is closed only when the ring is 476 * not closed 477 */ 478 if (mrp->ring_state != BR_MRP_RING_STATE_CLOSED) 479 br_mrp_port_open(port->dev, false); 480 } 481 482 /* This will just forward the frame to the other mrp ring port(MRC role) or will 483 * not do anything. 484 * note: already called with rcu_read_lock 485 */ 486 static int br_mrp_rcv(struct net_bridge_port *p, 487 struct sk_buff *skb, struct net_device *dev) 488 { 489 struct net_device *s_dev, *p_dev, *d_dev; 490 struct net_bridge_port *p_port, *s_port; 491 struct net_bridge *br; 492 struct sk_buff *nskb; 493 struct br_mrp *mrp; 494 495 /* If port is disabled don't accept any frames */ 496 if (p->state == BR_STATE_DISABLED) 497 return 0; 498 499 br = p->br; 500 mrp = br_mrp_find_port(br, p); 501 if (unlikely(!mrp)) 502 return 0; 503 504 p_port = rcu_dereference(mrp->p_port); 505 if (!p_port) 506 return 0; 507 508 s_port = rcu_dereference(mrp->s_port); 509 if (!s_port) 510 return 0; 511 512 /* If the role is MRM then don't forward the frames */ 513 if (mrp->ring_role == BR_MRP_RING_ROLE_MRM) { 514 br_mrp_mrm_process(mrp, p, skb); 515 return 1; 516 } 517 518 /* Clone the frame and forward it on the other MRP port */ 519 nskb = skb_clone(skb, GFP_ATOMIC); 520 if (!nskb) 521 return 0; 522 523 p_dev = p_port->dev; 524 s_dev = s_port->dev; 525 526 if (p_dev == dev) 527 d_dev = s_dev; 528 else 529 d_dev = p_dev; 530 531 nskb->dev = d_dev; 532 skb_push(nskb, ETH_HLEN); 533 dev_queue_xmit(nskb); 534 535 return 1; 536 } 537 538 /* Check if the frame was received on a port that is part of MRP ring 539 * and if the frame has MRP eth. In that case process the frame otherwise do 540 * normal forwarding. 541 * note: already called with rcu_read_lock 542 */ 543 int br_mrp_process(struct net_bridge_port *p, struct sk_buff *skb) 544 { 545 /* If there is no MRP instance do normal forwarding */ 546 if (likely(!(p->flags & BR_MRP_AWARE))) 547 goto out; 548 549 if (unlikely(skb->protocol == htons(ETH_P_MRP))) 550 return br_mrp_rcv(p, skb, p->dev); 551 552 out: 553 return 0; 554 } 555 556 bool br_mrp_enabled(struct net_bridge *br) 557 { 558 return !list_empty(&br->mrp_list); 559 } 560