net/bridge/br_mrp.c

   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 static const u8 mrp_in_test_dmac[ETH_ALEN] = { 0x1, 0x15, 0x4e, 0x0, 0x0, 0x3 };
   8
   9 static bool br_mrp_is_ring_port(struct net_bridge_port *p_port,
  10                                 struct net_bridge_port *s_port,
  11                                 struct net_bridge_port *port)
  12 {
  13         if (port == p_port ||
  14             port == s_port)
  15                 return true;
  16
  17         return false;
  18 }
  19
  20 static bool br_mrp_is_in_port(struct net_bridge_port *i_port,
  21                               struct net_bridge_port *port)
  22 {
  23         if (port == i_port)
  24                 return true;
  25
  26         return false;
  27 }
  28
  29 static struct net_bridge_port *br_mrp_get_port(struct net_bridge *br,
  30                                                u32 ifindex)
  31 {
  32         struct net_bridge_port *res = NULL;
  33         struct net_bridge_port *port;
  34
  35         list_for_each_entry(port, &br->port_list, list) {
  36                 if (port->dev->ifindex == ifindex) {
  37                         res = port;
  38                         break;
  39                 }
  40         }
  41
  42         return res;
  43 }
  44
  45 static struct br_mrp *br_mrp_find_id(struct net_bridge *br, u32 ring_id)
  46 {
  47         struct br_mrp *res = NULL;
  48         struct br_mrp *mrp;
  49
  50         list_for_each_entry_rcu(mrp, &br->mrp_list, list,
  51                                 lockdep_rtnl_is_held()) {
  52                 if (mrp->ring_id == ring_id) {
  53                         res = mrp;
  54                         break;
  55                 }
  56         }
  57
  58         return res;
  59 }
  60
  61 static struct br_mrp *br_mrp_find_in_id(struct net_bridge *br, u32 in_id)
  62 {
  63         struct br_mrp *res = NULL;
  64         struct br_mrp *mrp;
  65
  66         list_for_each_entry_rcu(mrp, &br->mrp_list, list,
  67                                 lockdep_rtnl_is_held()) {
  68                 if (mrp->in_id == in_id) {
  69                         res = mrp;
  70                         break;
  71                 }
  72         }
  73
  74         return res;
  75 }
  76
  77 static bool br_mrp_unique_ifindex(struct net_bridge *br, u32 ifindex)
  78 {
  79         struct br_mrp *mrp;
  80
  81         list_for_each_entry_rcu(mrp, &br->mrp_list, list,
  82                                 lockdep_rtnl_is_held()) {
  83                 struct net_bridge_port *p;
  84
  85                 p = rtnl_dereference(mrp->p_port);
  86                 if (p && p->dev->ifindex == ifindex)
  87                         return false;
  88
  89                 p = rtnl_dereference(mrp->s_port);
  90                 if (p && p->dev->ifindex == ifindex)
  91                         return false;
  92
  93                 p = rtnl_dereference(mrp->i_port);
  94                 if (p && p->dev->ifindex == ifindex)
  95                         return false;
  96         }
  97
  98         return true;
  99 }
 100
 101 static struct br_mrp *br_mrp_find_port(struct net_bridge *br,
 102                                        struct net_bridge_port *p)
 103 {
 104         struct br_mrp *res = NULL;
 105         struct br_mrp *mrp;
 106
 107         list_for_each_entry_rcu(mrp, &br->mrp_list, list,
 108                                 lockdep_rtnl_is_held()) {
 109                 if (rcu_access_pointer(mrp->p_port) == p ||
 110                     rcu_access_pointer(mrp->s_port) == p ||
 111                     rcu_access_pointer(mrp->i_port) == p) {
 112                         res = mrp;
 113                         break;
 114                 }
 115         }
 116
 117         return res;
 118 }
 119
 120 static int br_mrp_next_seq(struct br_mrp *mrp)
 121 {
 122         mrp->seq_id++;
 123         return mrp->seq_id;
 124 }
 125
 126 static struct sk_buff *br_mrp_skb_alloc(struct net_bridge_port *p,
 127                                         const u8 *src, const u8 *dst)
 128 {
 129         struct ethhdr *eth_hdr;
 130         struct sk_buff *skb;
 131         __be16 *version;
 132
 133         skb = dev_alloc_skb(MRP_MAX_FRAME_LENGTH);
 134         if (!skb)
 135                 return NULL;
 136
 137         skb->dev = p->dev;
 138         skb->protocol = htons(ETH_P_MRP);
 139         skb->priority = MRP_FRAME_PRIO;
 140         skb_reserve(skb, sizeof(*eth_hdr));
 141
 142         eth_hdr = skb_push(skb, sizeof(*eth_hdr));
 143         ether_addr_copy(eth_hdr->h_dest, dst);
 144         ether_addr_copy(eth_hdr->h_source, src);
 145         eth_hdr->h_proto = htons(ETH_P_MRP);
 146
 147         version = skb_put(skb, sizeof(*version));
 148         *version = cpu_to_be16(MRP_VERSION);
 149
 150         return skb;
 151 }
 152
 153 static void br_mrp_skb_tlv(struct sk_buff *skb,
 154                            enum br_mrp_tlv_header_type type,
 155                            u8 length)
 156 {
 157         struct br_mrp_tlv_hdr *hdr;
 158
 159         hdr = skb_put(skb, sizeof(*hdr));
 160         hdr->type = type;
 161         hdr->length = length;
 162 }
 163
 164 static void br_mrp_skb_common(struct sk_buff *skb, struct br_mrp *mrp)
 165 {
 166         struct br_mrp_common_hdr *hdr;
 167
 168         br_mrp_skb_tlv(skb, BR_MRP_TLV_HEADER_COMMON, sizeof(*hdr));
 169
 170         hdr = skb_put(skb, sizeof(*hdr));
 171         hdr->seq_id = cpu_to_be16(br_mrp_next_seq(mrp));
 172         memset(hdr->domain, 0xff, MRP_DOMAIN_UUID_LENGTH);
 173 }
 174
 175 static struct sk_buff *br_mrp_alloc_test_skb(struct br_mrp *mrp,
 176                                              struct net_bridge_port *p,
 177                                              enum br_mrp_port_role_type port_role)
 178 {
 179         struct br_mrp_ring_test_hdr *hdr = NULL;
 180         struct sk_buff *skb = NULL;
 181
 182         if (!p)
 183                 return NULL;
 184
 185         skb = br_mrp_skb_alloc(p, p->dev->dev_addr, mrp_test_dmac);
 186         if (!skb)
 187                 return NULL;
 188
 189         br_mrp_skb_tlv(skb, BR_MRP_TLV_HEADER_RING_TEST, sizeof(*hdr));
 190         hdr = skb_put(skb, sizeof(*hdr));
 191
 192         hdr->prio = cpu_to_be16(mrp->prio);
 193         ether_addr_copy(hdr->sa, p->br->dev->dev_addr);
 194         hdr->port_role = cpu_to_be16(port_role);
 195         hdr->state = cpu_to_be16(mrp->ring_state);
 196         hdr->transitions = cpu_to_be16(mrp->ring_transitions);
 197         hdr->timestamp = cpu_to_be32(jiffies_to_msecs(jiffies));
 198
 199         br_mrp_skb_common(skb, mrp);
 200         br_mrp_skb_tlv(skb, BR_MRP_TLV_HEADER_END, 0x0);
 201
 202         return skb;
 203 }
 204
 205 static struct sk_buff *br_mrp_alloc_in_test_skb(struct br_mrp *mrp,
 206                                                 struct net_bridge_port *p,
 207                                                 enum br_mrp_port_role_type port_role)
 208 {
 209         struct br_mrp_in_test_hdr *hdr = NULL;
 210         struct sk_buff *skb = NULL;
 211
 212         if (!p)
 213                 return NULL;
 214
 215         skb = br_mrp_skb_alloc(p, p->dev->dev_addr, mrp_in_test_dmac);
 216         if (!skb)
 217                 return NULL;
 218
 219         br_mrp_skb_tlv(skb, BR_MRP_TLV_HEADER_IN_TEST, sizeof(*hdr));
 220         hdr = skb_put(skb, sizeof(*hdr));
 221
 222         hdr->id = cpu_to_be16(mrp->in_id);
 223         ether_addr_copy(hdr->sa, p->br->dev->dev_addr);
 224         hdr->port_role = cpu_to_be16(port_role);
 225         hdr->state = cpu_to_be16(mrp->in_state);
 226         hdr->transitions = cpu_to_be16(mrp->in_transitions);
 227         hdr->timestamp = cpu_to_be32(jiffies_to_msecs(jiffies));
 228
 229         br_mrp_skb_common(skb, mrp);
 230         br_mrp_skb_tlv(skb, BR_MRP_TLV_HEADER_END, 0x0);
 231
 232         return skb;
 233 }
 234
 235 /* This function is continuously called in the following cases:
 236  * - when node role is MRM, in this case test_monitor is always set to false
 237  *   because it needs to notify the userspace that the ring is open and needs to
 238  *   send MRP_Test frames
 239  * - when node role is MRA, there are 2 subcases:
 240  *     - when MRA behaves as MRM, in this case is similar with MRM role
 241  *     - when MRA behaves as MRC, in this case test_monitor is set to true,
 242  *       because it needs to detect when it stops seeing MRP_Test frames
 243  *       from MRM node but it doesn't need to send MRP_Test frames.
 244  */
 245 static void br_mrp_test_work_expired(struct work_struct *work)
 246 {
 247         struct delayed_work *del_work = to_delayed_work(work);
 248         struct br_mrp *mrp = container_of(del_work, struct br_mrp, test_work);
 249         struct net_bridge_port *p;
 250         bool notify_open = false;
 251         struct sk_buff *skb;
 252
 253         if (time_before_eq(mrp->test_end, jiffies))
 254                 return;
 255
 256         if (mrp->test_count_miss < mrp->test_max_miss) {
 257                 mrp->test_count_miss++;
 258         } else {
 259                 /* Notify that the ring is open only if the ring state is
 260                  * closed, otherwise it would continue to notify at every
 261                  * interval.
 262                  * Also notify that the ring is open when the node has the
 263                  * role MRA and behaves as MRC. The reason is that the
 264                  * userspace needs to know when the MRM stopped sending
 265                  * MRP_Test frames so that the current node to try to take
 266                  * the role of a MRM.
 267                  */
 268                 if (mrp->ring_state == BR_MRP_RING_STATE_CLOSED ||
 269                     mrp->test_monitor)
 270                         notify_open = true;
 271         }
 272
 273         rcu_read_lock();
 274
 275         p = rcu_dereference(mrp->p_port);
 276         if (p) {
 277                 if (!mrp->test_monitor) {
 278                         skb = br_mrp_alloc_test_skb(mrp, p,
 279                                                     BR_MRP_PORT_ROLE_PRIMARY);
 280                         if (!skb)
 281                                 goto out;
 282
 283                         skb_reset_network_header(skb);
 284                         dev_queue_xmit(skb);
 285                 }
 286
 287                 if (notify_open && !mrp->ring_role_offloaded)
 288                         br_mrp_ring_port_open(p->dev, true);
 289         }
 290
 291         p = rcu_dereference(mrp->s_port);
 292         if (p) {
 293                 if (!mrp->test_monitor) {
 294                         skb = br_mrp_alloc_test_skb(mrp, p,
 295                                                     BR_MRP_PORT_ROLE_SECONDARY);
 296                         if (!skb)
 297                                 goto out;
 298
 299                         skb_reset_network_header(skb);
 300                         dev_queue_xmit(skb);
 301                 }
 302
 303                 if (notify_open && !mrp->ring_role_offloaded)
 304                         br_mrp_ring_port_open(p->dev, true);
 305         }
 306
 307 out:
 308         rcu_read_unlock();
 309
 310         queue_delayed_work(system_wq, &mrp->test_work,
 311                            usecs_to_jiffies(mrp->test_interval));
 312 }
 313
 314 /* This function is continuously called when the node has the interconnect role
 315  * MIM. It would generate interconnect test frames and will send them on all 3
 316  * ports. But will also check if it stop receiving interconnect test frames.
 317  */
 318 static void br_mrp_in_test_work_expired(struct work_struct *work)
 319 {
 320         struct delayed_work *del_work = to_delayed_work(work);
 321         struct br_mrp *mrp = container_of(del_work, struct br_mrp, in_test_work);
 322         struct net_bridge_port *p;
 323         bool notify_open = false;
 324         struct sk_buff *skb;
 325
 326         if (time_before_eq(mrp->in_test_end, jiffies))
 327                 return;
 328
 329         if (mrp->in_test_count_miss < mrp->in_test_max_miss) {
 330                 mrp->in_test_count_miss++;
 331         } else {
 332                 /* Notify that the interconnect ring is open only if the
 333                  * interconnect ring state is closed, otherwise it would
 334                  * continue to notify at every interval.
 335                  */
 336                 if (mrp->in_state == BR_MRP_IN_STATE_CLOSED)
 337                         notify_open = true;
 338         }
 339
 340         rcu_read_lock();
 341
 342         p = rcu_dereference(mrp->p_port);
 343         if (p) {
 344                 skb = br_mrp_alloc_in_test_skb(mrp, p,
 345                                                BR_MRP_PORT_ROLE_PRIMARY);
 346                 if (!skb)
 347                         goto out;
 348
 349                 skb_reset_network_header(skb);
 350                 dev_queue_xmit(skb);
 351
 352                 if (notify_open && !mrp->in_role_offloaded)
 353                         br_mrp_in_port_open(p->dev, true);
 354         }
 355
 356         p = rcu_dereference(mrp->s_port);
 357         if (p) {
 358                 skb = br_mrp_alloc_in_test_skb(mrp, p,
 359                                                BR_MRP_PORT_ROLE_SECONDARY);
 360                 if (!skb)
 361                         goto out;
 362
 363                 skb_reset_network_header(skb);
 364                 dev_queue_xmit(skb);
 365
 366                 if (notify_open && !mrp->in_role_offloaded)
 367                         br_mrp_in_port_open(p->dev, true);
 368         }
 369
 370         p = rcu_dereference(mrp->i_port);
 371         if (p) {
 372                 skb = br_mrp_alloc_in_test_skb(mrp, p,
 373                                                BR_MRP_PORT_ROLE_INTER);
 374                 if (!skb)
 375                         goto out;
 376
 377                 skb_reset_network_header(skb);
 378                 dev_queue_xmit(skb);
 379
 380                 if (notify_open && !mrp->in_role_offloaded)
 381                         br_mrp_in_port_open(p->dev, true);
 382         }
 383
 384 out:
 385         rcu_read_unlock();
 386
 387         queue_delayed_work(system_wq, &mrp->in_test_work,
 388                            usecs_to_jiffies(mrp->in_test_interval));
 389 }
 390
 391 /* Deletes the MRP instance.
 392  * note: called under rtnl_lock
 393  */
 394 static void br_mrp_del_impl(struct net_bridge *br, struct br_mrp *mrp)
 395 {
 396         struct net_bridge_port *p;
 397         u8 state;
 398
 399         /* Stop sending MRP_Test frames */
 400         cancel_delayed_work_sync(&mrp->test_work);
 401         br_mrp_switchdev_send_ring_test(br, mrp, 0, 0, 0, 0);
 402
 403         /* Stop sending MRP_InTest frames if has an interconnect role */
 404         cancel_delayed_work_sync(&mrp->in_test_work);
 405         br_mrp_switchdev_send_in_test(br, mrp, 0, 0, 0);
 406
 407         br_mrp_switchdev_del(br, mrp);
 408
 409         /* Reset the ports */
 410         p = rtnl_dereference(mrp->p_port);
 411         if (p) {
 412                 spin_lock_bh(&br->lock);
 413                 state = netif_running(br->dev) ?
 414                                 BR_STATE_FORWARDING : BR_STATE_DISABLED;
 415                 p->state = state;
 416                 p->flags &= ~BR_MRP_AWARE;
 417                 spin_unlock_bh(&br->lock);
 418                 br_mrp_port_switchdev_set_state(p, state);
 419                 rcu_assign_pointer(mrp->p_port, NULL);
 420         }
 421
 422         p = rtnl_dereference(mrp->s_port);
 423         if (p) {
 424                 spin_lock_bh(&br->lock);
 425                 state = netif_running(br->dev) ?
 426                                 BR_STATE_FORWARDING : BR_STATE_DISABLED;
 427                 p->state = state;
 428                 p->flags &= ~BR_MRP_AWARE;
 429                 spin_unlock_bh(&br->lock);
 430                 br_mrp_port_switchdev_set_state(p, state);
 431                 rcu_assign_pointer(mrp->s_port, NULL);
 432         }
 433
 434         p = rtnl_dereference(mrp->i_port);
 435         if (p) {
 436                 spin_lock_bh(&br->lock);
 437                 state = netif_running(br->dev) ?
 438                                 BR_STATE_FORWARDING : BR_STATE_DISABLED;
 439                 p->state = state;
 440                 p->flags &= ~BR_MRP_AWARE;
 441                 spin_unlock_bh(&br->lock);
 442                 br_mrp_port_switchdev_set_state(p, state);
 443                 rcu_assign_pointer(mrp->i_port, NULL);
 444         }
 445
 446         list_del_rcu(&mrp->list);
 447         kfree_rcu(mrp, rcu);
 448 }
 449
 450 /* Adds a new MRP instance.
 451  * note: called under rtnl_lock
 452  */
 453 int br_mrp_add(struct net_bridge *br, struct br_mrp_instance *instance)
 454 {
 455         struct net_bridge_port *p;
 456         struct br_mrp *mrp;
 457         int err;
 458
 459         /* If the ring exists, it is not possible to create another one with the
 460          * same ring_id
 461          */
 462         mrp = br_mrp_find_id(br, instance->ring_id);
 463         if (mrp)
 464                 return -EINVAL;
 465
 466         if (!br_mrp_get_port(br, instance->p_ifindex) ||
 467             !br_mrp_get_port(br, instance->s_ifindex))
 468                 return -EINVAL;
 469
 470         /* It is not possible to have the same port part of multiple rings */
 471         if (!br_mrp_unique_ifindex(br, instance->p_ifindex) ||
 472             !br_mrp_unique_ifindex(br, instance->s_ifindex))
 473                 return -EINVAL;
 474
 475         mrp = kzalloc(sizeof(*mrp), GFP_KERNEL);
 476         if (!mrp)
 477                 return -ENOMEM;
 478
 479         mrp->ring_id = instance->ring_id;
 480         mrp->prio = instance->prio;
 481
 482         p = br_mrp_get_port(br, instance->p_ifindex);
 483         spin_lock_bh(&br->lock);
 484         p->state = BR_STATE_FORWARDING;
 485         p->flags |= BR_MRP_AWARE;
 486         spin_unlock_bh(&br->lock);
 487         rcu_assign_pointer(mrp->p_port, p);
 488
 489         p = br_mrp_get_port(br, instance->s_ifindex);
 490         spin_lock_bh(&br->lock);
 491         p->state = BR_STATE_FORWARDING;
 492         p->flags |= BR_MRP_AWARE;
 493         spin_unlock_bh(&br->lock);
 494         rcu_assign_pointer(mrp->s_port, p);
 495
 496         INIT_DELAYED_WORK(&mrp->test_work, br_mrp_test_work_expired);
 497         INIT_DELAYED_WORK(&mrp->in_test_work, br_mrp_in_test_work_expired);
 498         list_add_tail_rcu(&mrp->list, &br->mrp_list);
 499
 500         err = br_mrp_switchdev_add(br, mrp);
 501         if (err)
 502                 goto delete_mrp;
 503
 504         return 0;
 505
 506 delete_mrp:
 507         br_mrp_del_impl(br, mrp);
 508
 509         return err;
 510 }
 511
 512 /* Deletes the MRP instance from which the port is part of
 513  * note: called under rtnl_lock
 514  */
 515 void br_mrp_port_del(struct net_bridge *br, struct net_bridge_port *p)
 516 {
 517         struct br_mrp *mrp = br_mrp_find_port(br, p);
 518
 519         /* If the port is not part of a MRP instance just bail out */
 520         if (!mrp)
 521                 return;
 522
 523         br_mrp_del_impl(br, mrp);
 524 }
 525
 526 /* Deletes existing MRP instance based on ring_id
 527  * note: called under rtnl_lock
 528  */
 529 int br_mrp_del(struct net_bridge *br, struct br_mrp_instance *instance)
 530 {
 531         struct br_mrp *mrp = br_mrp_find_id(br, instance->ring_id);
 532
 533         if (!mrp)
 534                 return -EINVAL;
 535
 536         br_mrp_del_impl(br, mrp);
 537
 538         return 0;
 539 }
 540
 541 /* Set port state, port state can be forwarding, blocked or disabled
 542  * note: already called with rtnl_lock
 543  */
 544 int br_mrp_set_port_state(struct net_bridge_port *p,
 545                           enum br_mrp_port_state_type state)
 546 {
 547         u32 port_state;
 548
 549         if (!p || !(p->flags & BR_MRP_AWARE))
 550                 return -EINVAL;
 551
 552         spin_lock_bh(&p->br->lock);
 553
 554         if (state == BR_MRP_PORT_STATE_FORWARDING)
 555                 port_state = BR_STATE_FORWARDING;
 556         else
 557                 port_state = BR_STATE_BLOCKING;
 558
 559         p->state = port_state;
 560         spin_unlock_bh(&p->br->lock);
 561
 562         br_mrp_port_switchdev_set_state(p, port_state);
 563
 564         return 0;
 565 }
 566
 567 /* Set port role, port role can be primary or secondary
 568  * note: already called with rtnl_lock
 569  */
 570 int br_mrp_set_port_role(struct net_bridge_port *p,
 571                          enum br_mrp_port_role_type role)
 572 {
 573         struct br_mrp *mrp;
 574
 575         if (!p || !(p->flags & BR_MRP_AWARE))
 576                 return -EINVAL;
 577
 578         mrp = br_mrp_find_port(p->br, p);
 579
 580         if (!mrp)
 581                 return -EINVAL;
 582
 583         switch (role) {
 584         case BR_MRP_PORT_ROLE_PRIMARY:
 585                 rcu_assign_pointer(mrp->p_port, p);
 586                 break;
 587         case BR_MRP_PORT_ROLE_SECONDARY:
 588                 rcu_assign_pointer(mrp->s_port, p);
 589                 break;
 590         default:
 591                 return -EINVAL;
 592         }
 593
 594         br_mrp_port_switchdev_set_role(p, role);
 595
 596         return 0;
 597 }
 598
 599 /* Set ring state, ring state can be only Open or Closed
 600  * note: already called with rtnl_lock
 601  */
 602 int br_mrp_set_ring_state(struct net_bridge *br,
 603                           struct br_mrp_ring_state *state)
 604 {
 605         struct br_mrp *mrp = br_mrp_find_id(br, state->ring_id);
 606
 607         if (!mrp)
 608                 return -EINVAL;
 609
 610         if (mrp->ring_state != state->ring_state)
 611                 mrp->ring_transitions++;
 612
 613         mrp->ring_state = state->ring_state;
 614
 615         br_mrp_switchdev_set_ring_state(br, mrp, state->ring_state);
 616
 617         return 0;
 618 }
 619
 620 /* Set ring role, ring role can be only MRM(Media Redundancy Manager) or
 621  * MRC(Media Redundancy Client).
 622  * note: already called with rtnl_lock
 623  */
 624 int br_mrp_set_ring_role(struct net_bridge *br,
 625                          struct br_mrp_ring_role *role)
 626 {
 627         struct br_mrp *mrp = br_mrp_find_id(br, role->ring_id);
 628         int err;
 629
 630         if (!mrp)
 631                 return -EINVAL;
 632
 633         mrp->ring_role = role->ring_role;
 634
 635         /* If there is an error just bailed out */
 636         err = br_mrp_switchdev_set_ring_role(br, mrp, role->ring_role);
 637         if (err && err != -EOPNOTSUPP)
 638                 return err;
 639
 640         /* Now detect if the HW actually applied the role or not. If the HW
 641          * applied the role it means that the SW will not to do those operations
 642          * anymore. For example if the role ir MRM then the HW will notify the
 643          * SW when ring is open, but if the is not pushed to the HW the SW will
 644          * need to detect when the ring is open
 645          */
 646         mrp->ring_role_offloaded = err == -EOPNOTSUPP ? 0 : 1;
 647
 648         return 0;
 649 }
 650
 651 /* Start to generate or monitor MRP test frames, the frames are generated by
 652  * HW and if it fails, they are generated by the SW.
 653  * note: already called with rtnl_lock
 654  */
 655 int br_mrp_start_test(struct net_bridge *br,
 656                       struct br_mrp_start_test *test)
 657 {
 658         struct br_mrp *mrp = br_mrp_find_id(br, test->ring_id);
 659
 660         if (!mrp)
 661                 return -EINVAL;
 662
 663         /* Try to push it to the HW and if it fails then continue with SW
 664          * implementation and if that also fails then return error.
 665          */
 666         if (!br_mrp_switchdev_send_ring_test(br, mrp, test->interval,
 667                                              test->max_miss, test->period,
 668                                              test->monitor))
 669                 return 0;
 670
 671         mrp->test_interval = test->interval;
 672         mrp->test_end = jiffies + usecs_to_jiffies(test->period);
 673         mrp->test_max_miss = test->max_miss;
 674         mrp->test_monitor = test->monitor;
 675         mrp->test_count_miss = 0;
 676         queue_delayed_work(system_wq, &mrp->test_work,
 677                            usecs_to_jiffies(test->interval));
 678
 679         return 0;
 680 }
 681
 682 /* Set in state, int state can be only Open or Closed
 683  * note: already called with rtnl_lock
 684  */
 685 int br_mrp_set_in_state(struct net_bridge *br, struct br_mrp_in_state *state)
 686 {
 687         struct br_mrp *mrp = br_mrp_find_in_id(br, state->in_id);
 688
 689         if (!mrp)
 690                 return -EINVAL;
 691
 692         if (mrp->in_state != state->in_state)
 693                 mrp->in_transitions++;
 694
 695         mrp->in_state = state->in_state;
 696
 697         br_mrp_switchdev_set_in_state(br, mrp, state->in_state);
 698
 699         return 0;
 700 }
 701
 702 /* Set in role, in role can be only MIM(Media Interconnection Manager) or
 703  * MIC(Media Interconnection Client).
 704  * note: already called with rtnl_lock
 705  */
 706 int br_mrp_set_in_role(struct net_bridge *br, struct br_mrp_in_role *role)
 707 {
 708         struct br_mrp *mrp = br_mrp_find_id(br, role->ring_id);
 709         struct net_bridge_port *p;
 710         int err;
 711
 712         if (!mrp)
 713                 return -EINVAL;
 714
 715         if (!br_mrp_get_port(br, role->i_ifindex))
 716                 return -EINVAL;
 717
 718         if (role->in_role == BR_MRP_IN_ROLE_DISABLED) {
 719                 u8 state;
 720
 721                 /* It is not allowed to disable a port that doesn't exist */
 722                 p = rtnl_dereference(mrp->i_port);
 723                 if (!p)
 724                         return -EINVAL;
 725
 726                 /* Stop the generating MRP_InTest frames */
 727                 cancel_delayed_work_sync(&mrp->in_test_work);
 728                 br_mrp_switchdev_send_in_test(br, mrp, 0, 0, 0);
 729
 730                 /* Remove the port */
 731                 spin_lock_bh(&br->lock);
 732                 state = netif_running(br->dev) ?
 733                                 BR_STATE_FORWARDING : BR_STATE_DISABLED;
 734                 p->state = state;
 735                 p->flags &= ~BR_MRP_AWARE;
 736                 spin_unlock_bh(&br->lock);
 737                 br_mrp_port_switchdev_set_state(p, state);
 738                 rcu_assign_pointer(mrp->i_port, NULL);
 739
 740                 mrp->in_role = role->in_role;
 741                 mrp->in_id = 0;
 742
 743                 return 0;
 744         }
 745
 746         /* It is not possible to have the same port part of multiple rings */
 747         if (!br_mrp_unique_ifindex(br, role->i_ifindex))
 748                 return -EINVAL;
 749
 750         /* It is not allowed to set a different interconnect port if the mrp
 751          * instance has already one. First it needs to be disabled and after
 752          * that set the new port
 753          */
 754         if (rcu_access_pointer(mrp->i_port))
 755                 return -EINVAL;
 756
 757         p = br_mrp_get_port(br, role->i_ifindex);
 758         spin_lock_bh(&br->lock);
 759         p->state = BR_STATE_FORWARDING;
 760         p->flags |= BR_MRP_AWARE;
 761         spin_unlock_bh(&br->lock);
 762         rcu_assign_pointer(mrp->i_port, p);
 763
 764         mrp->in_role = role->in_role;
 765         mrp->in_id = role->in_id;
 766
 767         /* If there is an error just bailed out */
 768         err = br_mrp_switchdev_set_in_role(br, mrp, role->in_id,
 769                                            role->ring_id, role->in_role);
 770         if (err && err != -EOPNOTSUPP)
 771                 return err;
 772
 773         /* Now detect if the HW actually applied the role or not. If the HW
 774          * applied the role it means that the SW will not to do those operations
 775          * anymore. For example if the role is MIM then the HW will notify the
 776          * SW when interconnect ring is open, but if the is not pushed to the HW
 777          * the SW will need to detect when the interconnect ring is open.
 778          */
 779         mrp->in_role_offloaded = err == -EOPNOTSUPP ? 0 : 1;
 780
 781         return 0;
 782 }
 783
 784 /* Start to generate MRP_InTest frames, the frames are generated by
 785  * HW and if it fails, they are generated by the SW.
 786  * note: already called with rtnl_lock
 787  */
 788 int br_mrp_start_in_test(struct net_bridge *br,
 789                          struct br_mrp_start_in_test *in_test)
 790 {
 791         struct br_mrp *mrp = br_mrp_find_in_id(br, in_test->in_id);
 792
 793         if (!mrp)
 794                 return -EINVAL;
 795
 796         if (mrp->in_role != BR_MRP_IN_ROLE_MIM)
 797                 return -EINVAL;
 798
 799         /* Try to push it to the HW and if it fails then continue with SW
 800          * implementation and if that also fails then return error.
 801          */
 802         if (!br_mrp_switchdev_send_in_test(br, mrp, in_test->interval,
 803                                            in_test->max_miss, in_test->period))
 804                 return 0;
 805
 806         mrp->in_test_interval = in_test->interval;
 807         mrp->in_test_end = jiffies + usecs_to_jiffies(in_test->period);
 808         mrp->in_test_max_miss = in_test->max_miss;
 809         mrp->in_test_count_miss = 0;
 810         queue_delayed_work(system_wq, &mrp->in_test_work,
 811                            usecs_to_jiffies(in_test->interval));
 812
 813         return 0;
 814 }
 815
 816 /* Determin if the frame type is a ring frame */
 817 static bool br_mrp_ring_frame(struct sk_buff *skb)
 818 {
 819         const struct br_mrp_tlv_hdr *hdr;
 820         struct br_mrp_tlv_hdr _hdr;
 821
 822         hdr = skb_header_pointer(skb, sizeof(uint16_t), sizeof(_hdr), &_hdr);
 823         if (!hdr)
 824                 return false;
 825
 826         if (hdr->type == BR_MRP_TLV_HEADER_RING_TEST ||
 827             hdr->type == BR_MRP_TLV_HEADER_RING_TOPO ||
 828             hdr->type == BR_MRP_TLV_HEADER_RING_LINK_DOWN ||
 829             hdr->type == BR_MRP_TLV_HEADER_RING_LINK_UP ||
 830             hdr->type == BR_MRP_TLV_HEADER_OPTION)
 831                 return true;
 832
 833         return false;
 834 }
 835
 836 /* Determin if the frame type is an interconnect frame */
 837 static bool br_mrp_in_frame(struct sk_buff *skb)
 838 {
 839         const struct br_mrp_tlv_hdr *hdr;
 840         struct br_mrp_tlv_hdr _hdr;
 841
 842         hdr = skb_header_pointer(skb, sizeof(uint16_t), sizeof(_hdr), &_hdr);
 843         if (!hdr)
 844                 return false;
 845
 846         if (hdr->type == BR_MRP_TLV_HEADER_IN_TEST ||
 847             hdr->type == BR_MRP_TLV_HEADER_IN_TOPO ||
 848             hdr->type == BR_MRP_TLV_HEADER_IN_LINK_DOWN ||
 849             hdr->type == BR_MRP_TLV_HEADER_IN_LINK_UP)
 850                 return true;
 851
 852         return false;
 853 }
 854
 855 /* Process only MRP Test frame. All the other MRP frames are processed by
 856  * userspace application
 857  * note: already called with rcu_read_lock
 858  */
 859 static void br_mrp_mrm_process(struct br_mrp *mrp, struct net_bridge_port *port,
 860                                struct sk_buff *skb)
 861 {
 862         const struct br_mrp_tlv_hdr *hdr;
 863         struct br_mrp_tlv_hdr _hdr;
 864
 865         /* Each MRP header starts with a version field which is 16 bits.
 866          * Therefore skip the version and get directly the TLV header.
 867          */
 868         hdr = skb_header_pointer(skb, sizeof(uint16_t), sizeof(_hdr), &_hdr);
 869         if (!hdr)
 870                 return;
 871
 872         if (hdr->type != BR_MRP_TLV_HEADER_RING_TEST)
 873                 return;
 874
 875         mrp->test_count_miss = 0;
 876
 877         /* Notify the userspace that the ring is closed only when the ring is
 878          * not closed
 879          */
 880         if (mrp->ring_state != BR_MRP_RING_STATE_CLOSED)
 881                 br_mrp_ring_port_open(port->dev, false);
 882 }
 883
 884 /* Determin if the test hdr has a better priority than the node */
 885 static bool br_mrp_test_better_than_own(struct br_mrp *mrp,
 886                                         struct net_bridge *br,
 887                                         const struct br_mrp_ring_test_hdr *hdr)
 888 {
 889         u16 prio = be16_to_cpu(hdr->prio);
 890
 891         if (prio < mrp->prio ||
 892             (prio == mrp->prio &&
 893             ether_addr_to_u64(hdr->sa) < ether_addr_to_u64(br->dev->dev_addr)))
 894                 return true;
 895
 896         return false;
 897 }
 898
 899 /* Process only MRP Test frame. All the other MRP frames are processed by
 900  * userspace application
 901  * note: already called with rcu_read_lock
 902  */
 903 static void br_mrp_mra_process(struct br_mrp *mrp, struct net_bridge *br,
 904                                struct net_bridge_port *port,
 905                                struct sk_buff *skb)
 906 {
 907         const struct br_mrp_ring_test_hdr *test_hdr;
 908         struct br_mrp_ring_test_hdr _test_hdr;
 909         const struct br_mrp_tlv_hdr *hdr;
 910         struct br_mrp_tlv_hdr _hdr;
 911
 912         /* Each MRP header starts with a version field which is 16 bits.
 913          * Therefore skip the version and get directly the TLV header.
 914          */
 915         hdr = skb_header_pointer(skb, sizeof(uint16_t), sizeof(_hdr), &_hdr);
 916         if (!hdr)
 917                 return;
 918
 919         if (hdr->type != BR_MRP_TLV_HEADER_RING_TEST)
 920                 return;
 921
 922         test_hdr = skb_header_pointer(skb, sizeof(uint16_t) + sizeof(_hdr),
 923                                       sizeof(_test_hdr), &_test_hdr);
 924         if (!test_hdr)
 925                 return;
 926
 927         /* Only frames that have a better priority than the node will
 928          * clear the miss counter because otherwise the node will need to behave
 929          * as MRM.
 930          */
 931         if (br_mrp_test_better_than_own(mrp, br, test_hdr))
 932                 mrp->test_count_miss = 0;
 933 }
 934
 935 /* Process only MRP InTest frame. All the other MRP frames are processed by
 936  * userspace application
 937  * note: already called with rcu_read_lock
 938  */
 939 static bool br_mrp_mim_process(struct br_mrp *mrp, struct net_bridge_port *port,
 940                                struct sk_buff *skb)
 941 {
 942         const struct br_mrp_in_test_hdr *in_hdr;
 943         struct br_mrp_in_test_hdr _in_hdr;
 944         const struct br_mrp_tlv_hdr *hdr;
 945         struct br_mrp_tlv_hdr _hdr;
 946
 947         /* Each MRP header starts with a version field which is 16 bits.
 948          * Therefore skip the version and get directly the TLV header.
 949          */
 950         hdr = skb_header_pointer(skb, sizeof(uint16_t), sizeof(_hdr), &_hdr);
 951         if (!hdr)
 952                 return false;
 953
 954         /* The check for InTest frame type was already done */
 955         in_hdr = skb_header_pointer(skb, sizeof(uint16_t) + sizeof(_hdr),
 956                                     sizeof(_in_hdr), &_in_hdr);
 957         if (!in_hdr)
 958                 return false;
 959
 960         /* It needs to process only it's own InTest frames. */
 961         if (mrp->in_id != ntohs(in_hdr->id))
 962                 return false;
 963
 964         mrp->in_test_count_miss = 0;
 965
 966         /* Notify the userspace that the ring is closed only when the ring is
 967          * not closed
 968          */
 969         if (mrp->in_state != BR_MRP_IN_STATE_CLOSED)
 970                 br_mrp_in_port_open(port->dev, false);
 971
 972         return true;
 973 }
 974
 975 /* Get the MRP frame type
 976  * note: already called with rcu_read_lock
 977  */
 978 static u8 br_mrp_get_frame_type(struct sk_buff *skb)
 979 {
 980         const struct br_mrp_tlv_hdr *hdr;
 981         struct br_mrp_tlv_hdr _hdr;
 982
 983         /* Each MRP header starts with a version field which is 16 bits.
 984          * Therefore skip the version and get directly the TLV header.
 985          */
 986         hdr = skb_header_pointer(skb, sizeof(uint16_t), sizeof(_hdr), &_hdr);
 987         if (!hdr)
 988                 return 0xff;
 989
 990         return hdr->type;
 991 }
 992
 993 static bool br_mrp_mrm_behaviour(struct br_mrp *mrp)
 994 {
 995         if (mrp->ring_role == BR_MRP_RING_ROLE_MRM ||
 996             (mrp->ring_role == BR_MRP_RING_ROLE_MRA && !mrp->test_monitor))
 997                 return true;
 998
 999         return false;
1000 }
1001
1002 static bool br_mrp_mrc_behaviour(struct br_mrp *mrp)
1003 {
1004         if (mrp->ring_role == BR_MRP_RING_ROLE_MRC ||
1005             (mrp->ring_role == BR_MRP_RING_ROLE_MRA && mrp->test_monitor))
1006                 return true;
1007
1008         return false;
1009 }
1010
1011 /* This will just forward the frame to the other mrp ring ports, depending on
1012  * the frame type, ring role and interconnect role
1013  * note: already called with rcu_read_lock
1014  */
1015 static int br_mrp_rcv(struct net_bridge_port *p,
1016                       struct sk_buff *skb, struct net_device *dev)
1017 {
1018         struct net_bridge_port *p_port, *s_port, *i_port = NULL;
1019         struct net_bridge_port *p_dst, *s_dst, *i_dst = NULL;
1020         struct net_bridge *br;
1021         struct br_mrp *mrp;
1022
1023         /* If port is disabled don't accept any frames */
1024         if (p->state == BR_STATE_DISABLED)
1025                 return 0;
1026
1027         br = p->br;
1028         mrp =  br_mrp_find_port(br, p);
1029         if (unlikely(!mrp))
1030                 return 0;
1031
1032         p_port = rcu_dereference(mrp->p_port);
1033         if (!p_port)
1034                 return 0;
1035         p_dst = p_port;
1036
1037         s_port = rcu_dereference(mrp->s_port);
1038         if (!s_port)
1039                 return 0;
1040         s_dst = s_port;
1041
1042         /* If the frame is a ring frame then it is not required to check the
1043          * interconnect role and ports to process or forward the frame
1044          */
1045         if (br_mrp_ring_frame(skb)) {
1046                 /* If the role is MRM then don't forward the frames */
1047                 if (mrp->ring_role == BR_MRP_RING_ROLE_MRM) {
1048                         br_mrp_mrm_process(mrp, p, skb);
1049                         goto no_forward;
1050                 }
1051
1052                 /* If the role is MRA then don't forward the frames if it
1053                  * behaves as MRM node
1054                  */
1055                 if (mrp->ring_role == BR_MRP_RING_ROLE_MRA) {
1056                         if (!mrp->test_monitor) {
1057                                 br_mrp_mrm_process(mrp, p, skb);
1058                                 goto no_forward;
1059                         }
1060
1061                         br_mrp_mra_process(mrp, br, p, skb);
1062                 }
1063
1064                 goto forward;
1065         }
1066
1067         if (br_mrp_in_frame(skb)) {
1068                 u8 in_type = br_mrp_get_frame_type(skb);
1069
1070                 i_port = rcu_dereference(mrp->i_port);
1071                 i_dst = i_port;
1072
1073                 /* If the ring port is in block state it should not forward
1074                  * In_Test frames
1075                  */
1076                 if (br_mrp_is_ring_port(p_port, s_port, p) &&
1077                     p->state == BR_STATE_BLOCKING &&
1078                     in_type == BR_MRP_TLV_HEADER_IN_TEST)
1079                         goto no_forward;
1080
1081                 /* Nodes that behaves as MRM needs to stop forwarding the
1082                  * frames in case the ring is closed, otherwise will be a loop.
1083                  * In this case the frame is no forward between the ring ports.
1084                  */
1085                 if (br_mrp_mrm_behaviour(mrp) &&
1086                     br_mrp_is_ring_port(p_port, s_port, p) &&
1087                     (s_port->state != BR_STATE_FORWARDING ||
1088                      p_port->state != BR_STATE_FORWARDING)) {
1089                         p_dst = NULL;
1090                         s_dst = NULL;
1091                 }
1092
1093                 /* A node that behaves as MRC and doesn't have a interconnect
1094                  * role then it should forward all frames between the ring ports
1095                  * because it doesn't have an interconnect port
1096                  */
1097                 if (br_mrp_mrc_behaviour(mrp) &&
1098                     mrp->in_role == BR_MRP_IN_ROLE_DISABLED)
1099                         goto forward;
1100
1101                 if (mrp->in_role == BR_MRP_IN_ROLE_MIM) {
1102                         if (in_type == BR_MRP_TLV_HEADER_IN_TEST) {
1103                                 /* MIM should not forward it's own InTest
1104                                  * frames
1105                                  */
1106                                 if (br_mrp_mim_process(mrp, p, skb)) {
1107                                         goto no_forward;
1108                                 } else {
1109                                         if (br_mrp_is_ring_port(p_port, s_port,
1110                                                                 p))
1111                                                 i_dst = NULL;
1112
1113                                         if (br_mrp_is_in_port(i_port, p))
1114                                                 goto no_forward;
1115                                 }
1116                         } else {
1117                                 /* MIM should forward IntLinkChange and
1118                                  * IntTopoChange between ring ports but MIM
1119                                  * should not forward IntLinkChange and
1120                                  * IntTopoChange if the frame was received at
1121                                  * the interconnect port
1122                                  */
1123                                 if (br_mrp_is_ring_port(p_port, s_port, p))
1124                                         i_dst = NULL;
1125
1126                                 if (br_mrp_is_in_port(i_port, p))
1127                                         goto no_forward;
1128                         }
1129                 }
1130
1131                 if (mrp->in_role == BR_MRP_IN_ROLE_MIC) {
1132                         /* MIC should forward InTest frames on all ports
1133                          * regardless of the received port
1134                          */
1135                         if (in_type == BR_MRP_TLV_HEADER_IN_TEST)
1136                                 goto forward;
1137
1138                         /* MIC should forward IntLinkChange frames only if they
1139                          * are received on ring ports to all the ports
1140                          */
1141                         if (br_mrp_is_ring_port(p_port, s_port, p) &&
1142                             (in_type == BR_MRP_TLV_HEADER_IN_LINK_UP ||
1143                              in_type == BR_MRP_TLV_HEADER_IN_LINK_DOWN))
1144                                 goto forward;
1145
1146                         /* Should forward the InTopo frames only between the
1147                          * ring ports
1148                          */
1149                         if (in_type == BR_MRP_TLV_HEADER_IN_TOPO) {
1150                                 i_dst = NULL;
1151                                 goto forward;
1152                         }
1153
1154                         /* In all the other cases don't forward the frames */
1155                         goto no_forward;
1156                 }
1157         }
1158
1159 forward:
1160         if (p_dst)
1161                 br_forward(p_dst, skb, true, false);
1162         if (s_dst)
1163                 br_forward(s_dst, skb, true, false);
1164         if (i_dst)
1165                 br_forward(i_dst, skb, true, false);
1166
1167 no_forward:
1168         return 1;
1169 }
1170
1171 /* Check if the frame was received on a port that is part of MRP ring
1172  * and if the frame has MRP eth. In that case process the frame otherwise do
1173  * normal forwarding.
1174  * note: already called with rcu_read_lock
1175  */
1176 int br_mrp_process(struct net_bridge_port *p, struct sk_buff *skb)
1177 {
1178         /* If there is no MRP instance do normal forwarding */
1179         if (likely(!(p->flags & BR_MRP_AWARE)))
1180                 goto out;
1181
1182         if (unlikely(skb->protocol == htons(ETH_P_MRP)))
1183                 return br_mrp_rcv(p, skb, p->dev);
1184
1185 out:
1186         return 0;
1187 }
1188
1189 bool br_mrp_enabled(struct net_bridge *br)
1190 {
1191         return !list_empty(&br->mrp_list);
1192 }