lnet/lnet/router.c

   1 /*
   2  * Copyright (c) 2007, 2010, Oracle and/or its affiliates. All rights reserved.
   3  *
   4  * Copyright (c) 2011, 2017, Intel Corporation.
   5  *
   6  *   This file is part of Lustre, https://wiki.whamcloud.com/
   7  *
   8  *   Portals is free software; you can redistribute it and/or
   9  *   modify it under the terms of version 2 of the GNU General Public
  10  *   License as published by the Free Software Foundation.
  11  *
  12  *   Portals is distributed in the hope that it will be useful,
  13  *   but WITHOUT ANY WARRANTY; without even the implied warranty of
  14  *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15  *   GNU General Public License for more details.
  16  *
  17  *   You should have received a copy of the GNU General Public License
  18  *   along with Portals; if not, write to the Free Software
  19  *   Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
  20  *
  21  */
  22
  23 #define DEBUG_SUBSYSTEM S_LNET
  24
  25 #include <linux/random.h>
  26 #include <lnet/lib-lnet.h>
  27
  28 #define LNET_NRB_TINY_MIN       512     /* min value for each CPT */
  29 #define LNET_NRB_TINY           (LNET_NRB_TINY_MIN * 4)
  30 #define LNET_NRB_SMALL_MIN      4096    /* min value for each CPT */
  31 #define LNET_NRB_SMALL          (LNET_NRB_SMALL_MIN * 4)
  32 #define LNET_NRB_SMALL_PAGES    1
  33 #define LNET_NRB_LARGE_MIN      256     /* min value for each CPT */
  34 #define LNET_NRB_LARGE          (LNET_NRB_LARGE_MIN * 4)
  35 #define LNET_NRB_LARGE_PAGES    ((LNET_MTU + PAGE_SIZE - 1) >> \
  36                                   PAGE_SHIFT)
  37
  38 static char *forwarding = "";
  39 module_param(forwarding, charp, 0444);
  40 MODULE_PARM_DESC(forwarding, "Explicitly enable/disable forwarding between networks");
  41
  42 static int tiny_router_buffers;
  43 module_param(tiny_router_buffers, int, 0444);
  44 MODULE_PARM_DESC(tiny_router_buffers, "# of 0 payload messages to buffer in the router");
  45 static int small_router_buffers;
  46 module_param(small_router_buffers, int, 0444);
  47 MODULE_PARM_DESC(small_router_buffers, "# of small (1 page) messages to buffer in the router");
  48 static int large_router_buffers;
  49 module_param(large_router_buffers, int, 0444);
  50 MODULE_PARM_DESC(large_router_buffers, "# of large messages to buffer in the router");
  51 static int peer_buffer_credits;
  52 module_param(peer_buffer_credits, int, 0444);
  53 MODULE_PARM_DESC(peer_buffer_credits, "# router buffer credits per peer");
  54
  55 static int auto_down = 1;
  56 module_param(auto_down, int, 0444);
  57 MODULE_PARM_DESC(auto_down, "Automatically mark peers down on comms error");
  58
  59 int
  60 lnet_peer_buffer_credits(struct lnet_net *net)
  61 {
  62         /* NI option overrides LNet default */
  63         if (net->net_tunables.lct_peer_rtr_credits > 0)
  64                 return net->net_tunables.lct_peer_rtr_credits;
  65         if (peer_buffer_credits > 0)
  66                 return peer_buffer_credits;
  67
  68         /* As an approximation, allow this peer the same number of router
  69          * buffers as it is allowed outstanding sends */
  70         return net->net_tunables.lct_peer_tx_credits;
  71 }
  72
  73 static int check_routers_before_use;
  74 module_param(check_routers_before_use, int, 0444);
  75 MODULE_PARM_DESC(check_routers_before_use, "Assume routers are down and ping them before use");
  76
  77 int avoid_asym_router_failure = 1;
  78 module_param(avoid_asym_router_failure, int, 0644);
  79 MODULE_PARM_DESC(avoid_asym_router_failure, "Avoid asymmetrical router failures (0 to disable)");
  80
  81 int dead_router_check_interval = INT_MIN;
  82 module_param(dead_router_check_interval, int, 0444);
  83 MODULE_PARM_DESC(dead_router_check_interval, "(DEPRECATED - Use alive_router_check_interval)");
  84
  85 int live_router_check_interval = INT_MIN;
  86 module_param(live_router_check_interval, int, 0444);
  87 MODULE_PARM_DESC(live_router_check_interval, "(DEPRECATED - Use alive_router_check_interval)");
  88
  89 int alive_router_check_interval = 60;
  90 module_param(alive_router_check_interval, int, 0644);
  91 MODULE_PARM_DESC(alive_router_check_interval, "Seconds between live router health checks (<= 0 to disable)");
  92
  93 static int router_ping_timeout = 50;
  94 module_param(router_ping_timeout, int, 0644);
  95 MODULE_PARM_DESC(router_ping_timeout, "Seconds to wait for the reply to a router health query");
  96
  97 /*
  98  * A value between 0 and 100. 0 meaning that even if router's interfaces
  99  * have the worse health still consider the gateway usable.
 100  * 100 means that at least one interface on the route's remote net is 100%
 101  * healthy to consider the route alive.
 102  * The default is set to 100 to ensure we maintain the original behavior.
 103  */
 104 unsigned int router_sensitivity_percentage = 100;
 105 static int rtr_sensitivity_set(const char *val, cfs_kernel_param_arg_t *kp);
 106 static struct kernel_param_ops param_ops_rtr_sensitivity = {
 107         .set = rtr_sensitivity_set,
 108         .get = param_get_int,
 109 };
 110 #define param_check_rtr_sensitivity(name, p) \
 111                 __param_check(name, p, int)
 112 #ifdef HAVE_KERNEL_PARAM_OPS
 113 module_param(router_sensitivity_percentage, rtr_sensitivity, S_IRUGO|S_IWUSR);
 114 #else
 115 module_param_call(router_sensitivity_percentage, rtr_sensitivity_set, param_get_int,
 116                   &router_sensitivity_percentage, S_IRUGO|S_IWUSR);
 117 #endif
 118 MODULE_PARM_DESC(router_sensitivity_percentage,
 119                 "How healthy a gateway should be to be used in percent");
 120
 121 static int
 122 rtr_sensitivity_set(const char *val, cfs_kernel_param_arg_t *kp)
 123 {
 124         int rc;
 125         unsigned *sen = (unsigned *)kp->arg;
 126         unsigned long value;
 127
 128         rc = kstrtoul(val, 0, &value);
 129         if (rc) {
 130                 CERROR("Invalid module parameter value for 'router_sensitivity_percentage'\n");
 131                 return rc;
 132         }
 133
 134         if (value < 0 || value > 100) {
 135                 CERROR("Invalid value: %lu for 'router_sensitivity_percentage'\n", value);
 136                 return -EINVAL;
 137         }
 138
 139         /*
 140          * The purpose of locking the api_mutex here is to ensure that
 141          * the correct value ends up stored properly.
 142          */
 143         mutex_lock(&the_lnet.ln_api_mutex);
 144
 145         *sen = value;
 146
 147         mutex_unlock(&the_lnet.ln_api_mutex);
 148
 149         return 0;
 150 }
 151
 152 void
 153 lnet_rtr_transfer_to_peer(struct lnet_peer *src, struct lnet_peer *target)
 154 {
 155         struct lnet_route *route;
 156
 157         lnet_net_lock(LNET_LOCK_EX);
 158         target->lp_rtr_refcount += src->lp_rtr_refcount;
 159         /* move the list of queued messages to the new peer */
 160         list_splice_init(&src->lp_rtrq, &target->lp_rtrq);
 161         /* move all the routes that reference the peer */
 162         list_splice_init(&src->lp_routes, &target->lp_routes);
 163         /* update all the routes to point to the new peer */
 164         list_for_each_entry(route, &target->lp_routes, lr_gwlist)
 165                 route->lr_gateway = target;
 166         /* remove the old peer from the ln_routers list */
 167         list_del_init(&src->lp_rtr_list);
 168         /* add the new peer to the ln_routers list */
 169         if (list_empty(&target->lp_rtr_list)) {
 170                 lnet_peer_addref_locked(target);
 171                 list_add_tail(&target->lp_rtr_list, &the_lnet.ln_routers);
 172         }
 173         /* reset the ref count on the old peer and decrement its ref count */
 174         src->lp_rtr_refcount = 0;
 175         lnet_peer_decref_locked(src);
 176         /* update the router version */
 177         the_lnet.ln_routers_version++;
 178         lnet_net_unlock(LNET_LOCK_EX);
 179 }
 180
 181 int
 182 lnet_peers_start_down(void)
 183 {
 184         return check_routers_before_use;
 185 }
 186
 187 /*
 188  * The peer_net of a gateway is alive if at least one of the peer_ni's on
 189  * that peer_net is alive.
 190  */
 191 static bool
 192 lnet_is_gateway_net_alive(struct lnet_peer_net *lpn)
 193 {
 194         struct lnet_peer_ni *lpni;
 195
 196         list_for_each_entry(lpni, &lpn->lpn_peer_nis, lpni_peer_nis) {
 197                 if (lnet_is_peer_ni_alive(lpni))
 198                         return true;
 199         }
 200
 201         return false;
 202 }
 203
 204 /*
 205  * a gateway is alive only if all its nets are alive
 206  * called with cpt lock held
 207  */
 208 bool lnet_is_gateway_alive(struct lnet_peer *gw)
 209 {
 210         struct lnet_peer_net *lpn;
 211
 212         if (!gw->lp_alive)
 213                 return false;
 214
 215         list_for_each_entry(lpn, &gw->lp_peer_nets, lpn_peer_nets) {
 216                 if (!lnet_is_gateway_net_alive(lpn))
 217                         return false;
 218         }
 219
 220         return true;
 221 }
 222
 223 /*
 224  * lnet_is_route_alive() needs to be called with cpt lock held
 225  * A route is alive if the gateway can route between the local network and
 226  * the remote network of the route.
 227  * This means at least one NI is alive on each of the local and remote
 228  * networks of the gateway.
 229  */
 230 bool lnet_is_route_alive(struct lnet_route *route)
 231 {
 232         struct lnet_peer *gw = route->lr_gateway;
 233         struct lnet_peer_net *llpn;
 234         struct lnet_peer_net *rlpn;
 235
 236         /* If the gateway is down then all routes are considered down */
 237         if (!gw->lp_alive)
 238                 return false;
 239
 240         /*
 241          * if discovery is disabled then rely on the cached aliveness
 242          * information. This is handicapped information which we log when
 243          * we receive the discovery ping response. The most uptodate
 244          * aliveness information can only be obtained when discovery is
 245          * enabled.
 246          */
 247         if (lnet_is_discovery_disabled(gw))
 248                 return route->lr_alive;
 249
 250         /*
 251          * check the gateway's interfaces on the local network
 252          */
 253         llpn = lnet_peer_get_net_locked(gw, route->lr_lnet);
 254         if (!llpn)
 255                 return false;
 256
 257         if (!lnet_is_gateway_net_alive(llpn))
 258                 return false;
 259
 260         if (avoid_asym_router_failure) {
 261                 /* Check the gateway's interfaces on the remote network */
 262                 rlpn = lnet_peer_get_net_locked(gw, route->lr_net);
 263                 if (!rlpn)
 264                         return false;
 265                 if (!lnet_is_gateway_net_alive(rlpn))
 266                         return false;
 267         }
 268
 269         spin_lock(&gw->lp_lock);
 270         if (!(gw->lp_state & LNET_PEER_ROUTER_ENABLED)) {
 271                 spin_unlock(&gw->lp_lock);
 272                 if (gw->lp_rtr_refcount > 0)
 273                         CERROR("peer %s is being used as a gateway but routing feature is not turned on\n",
 274                                libcfs_nid2str(gw->lp_primary_nid));
 275                 return false;
 276         }
 277         spin_unlock(&gw->lp_lock);
 278
 279         return true;
 280 }
 281
 282 void
 283 lnet_consolidate_routes_locked(struct lnet_peer *orig_lp,
 284                                struct lnet_peer *new_lp)
 285 {
 286         struct lnet_peer_ni *lpni;
 287         struct lnet_route *route;
 288
 289         /*
 290          * Although a route is correlated with a peer, but when it's added
 291          * a specific NID is used. That NID refers to a peer_ni within
 292          * a peer. There could be other peer_nis on the same net, which
 293          * can be used to send to that gateway. However when we are
 294          * consolidating gateways because of discovery, the nid used to
 295          * add the route might've moved between gateway peers. In this
 296          * case we want to move the route to the new gateway as well. The
 297          * intent here is not to confuse the user who added the route.
 298          */
 299         list_for_each_entry(route, &orig_lp->lp_routes, lr_gwlist) {
 300                 lpni = lnet_peer_get_ni_locked(orig_lp, route->lr_nid);
 301                 if (!lpni) {
 302                         lnet_net_lock(LNET_LOCK_EX);
 303                         list_move(&route->lr_gwlist, &new_lp->lp_routes);
 304                         lnet_net_unlock(LNET_LOCK_EX);
 305                 }
 306         }
 307
 308 }
 309
 310 static inline void
 311 lnet_set_route_aliveness(struct lnet_route *route, bool alive)
 312 {
 313         /* Log when there's a state change */
 314         if (route->lr_alive != alive) {
 315                 CERROR("route to %s through %s has gone from %s to %s\n",
 316                        libcfs_net2str(route->lr_net),
 317                        libcfs_nid2str(route->lr_gateway->lp_primary_nid),
 318                        (route->lr_alive) ? "up" : "down",
 319                        alive ? "up" : "down");
 320                 route->lr_alive = alive;
 321         }
 322 }
 323
 324 void
 325 lnet_router_discovery_ping_reply(struct lnet_peer *lp)
 326 {
 327         struct lnet_ping_buffer *pbuf = lp->lp_data;
 328         struct lnet_remotenet *rnet;
 329         struct lnet_peer_net *llpn;
 330         struct lnet_route *route;
 331         bool net_up = false;
 332         unsigned lp_state;
 333         __u32 net, net2;
 334         int i, j;
 335
 336
 337         spin_lock(&lp->lp_lock);
 338         lp_state = lp->lp_state;
 339
 340         /* only handle replies if discovery is disabled. */
 341         if (!lnet_is_discovery_disabled_locked(lp)) {
 342                 spin_unlock(&lp->lp_lock);
 343                 return;
 344         }
 345
 346         spin_unlock(&lp->lp_lock);
 347
 348         if (lp_state & LNET_PEER_PING_FAILED ||
 349             pbuf->pb_info.pi_features & LNET_PING_FEAT_RTE_DISABLED) {
 350                 CDEBUG(D_NET, "Set routes down for gw %s because %s %d\n",
 351                        libcfs_nid2str(lp->lp_primary_nid),
 352                        lp_state & LNET_PEER_PING_FAILED ? "ping failed" :
 353                        "route feature is disabled", lp->lp_ping_error);
 354                 /* If the ping failed or the peer has routing disabled then
 355                  * mark the routes served by this peer down
 356                  */
 357                 list_for_each_entry(route, &lp->lp_routes, lr_gwlist)
 358                         lnet_set_route_aliveness(route, false);
 359                 return;
 360         }
 361
 362         CDEBUG(D_NET, "Discovery is disabled. Processing reply for gw: %s\n",
 363                libcfs_nid2str(lp->lp_primary_nid));
 364
 365         /*
 366          * examine the ping response:
 367          * For each NID in the ping response, extract the net
 368          * if the net exists on our remote net list then
 369          * iterate over the routes on the rnet and if:
 370          *      The route's local net is healthy and
 371          *      The remote net status is UP, then mark the route up
 372          * otherwise mark the route down
 373          */
 374         for (i = 1; i < pbuf->pb_info.pi_nnis; i++) {
 375                 net = LNET_NIDNET(pbuf->pb_info.pi_ni[i].ns_nid);
 376                 rnet = lnet_find_rnet_locked(net);
 377                 if (!rnet)
 378                         continue;
 379                 list_for_each_entry(route, &rnet->lrn_routes, lr_list) {
 380                         /* check if this is the route's gateway */
 381                         if (lp->lp_primary_nid !=
 382                             route->lr_gateway->lp_primary_nid)
 383                                 continue;
 384
 385                         llpn = lnet_peer_get_net_locked(lp, route->lr_lnet);
 386                         if (!llpn) {
 387                                 lnet_set_route_aliveness(route, false);
 388                                 continue;
 389                         }
 390
 391                         if (!lnet_is_gateway_net_alive(llpn)) {
 392                                 lnet_set_route_aliveness(route, false);
 393                                 continue;
 394                         }
 395
 396                         if (avoid_asym_router_failure &&
 397                             pbuf->pb_info.pi_ni[i].ns_status !=
 398                                 LNET_NI_STATUS_UP) {
 399                                 net_up = false;
 400
 401                                 /*
 402                                  * revisit all previous NIDs and check if
 403                                  * any on the network we're examining is
 404                                  * up. If at least one is up then we consider
 405                                  * the route to be alive.
 406                                  */
 407                                 for (j = 1; j < i; j++) {
 408                                         net2 = LNET_NIDNET(pbuf->pb_info.
 409                                                            pi_ni[j].ns_nid);
 410                                         if (net2 == net &&
 411                                             pbuf->pb_info.pi_ni[j].ns_status ==
 412                                                 LNET_NI_STATUS_UP)
 413                                                 net_up = true;
 414                                 }
 415                                 if (!net_up) {
 416                                         lnet_set_route_aliveness(route, false);
 417                                         continue;
 418                                 }
 419                         }
 420
 421                         lnet_set_route_aliveness(route, true);
 422                 }
 423         }
 424 }
 425
 426 void
 427 lnet_router_discovery_complete(struct lnet_peer *lp)
 428 {
 429         struct lnet_peer_ni *lpni = NULL;
 430         struct lnet_route *route;
 431
 432         spin_lock(&lp->lp_lock);
 433         lp->lp_state &= ~LNET_PEER_RTR_DISCOVERY;
 434         lp->lp_state |= LNET_PEER_RTR_DISCOVERED;
 435         lp->lp_alive = lp->lp_dc_error == 0;
 436         spin_unlock(&lp->lp_lock);
 437
 438         /*
 439          * Router discovery successful? All peer information would've been
 440          * updated already. No need to do any more processing
 441          */
 442         if (lp->lp_alive)
 443                 return;
 444
 445         /*
 446          * We do not send messages directly to the remote interfaces
 447          * of an LNet router. As such, we rely on the PING response
 448          * to determine the up/down status of these interfaces. If
 449          * a PING response is not receieved, or some other problem with
 450          * discovery occurs that prevents us from getting this status,
 451          * we assume all interfaces are down until we're able to
 452          * determine otherwise.
 453          */
 454         CDEBUG(D_NET, "%s: Router discovery failed %d\n",
 455                libcfs_nid2str(lp->lp_primary_nid), lp->lp_dc_error);
 456         while ((lpni = lnet_get_next_peer_ni_locked(lp, NULL, lpni)) != NULL)
 457                 lpni->lpni_ns_status = LNET_NI_STATUS_DOWN;
 458
 459         list_for_each_entry(route, &lp->lp_routes, lr_gwlist)
 460                 lnet_set_route_aliveness(route, false);
 461 }
 462
 463 static void
 464 lnet_rtr_addref_locked(struct lnet_peer *lp)
 465 {
 466         LASSERT(lp->lp_rtr_refcount >= 0);
 467
 468         /* lnet_net_lock must be exclusively locked */
 469         lp->lp_rtr_refcount++;
 470         if (lp->lp_rtr_refcount == 1) {
 471                 list_add_tail(&lp->lp_rtr_list, &the_lnet.ln_routers);
 472                 /* addref for the_lnet.ln_routers */
 473                 lnet_peer_addref_locked(lp);
 474                 the_lnet.ln_routers_version++;
 475         }
 476 }
 477
 478 static void
 479 lnet_rtr_decref_locked(struct lnet_peer *lp)
 480 {
 481         LASSERT(atomic_read(&lp->lp_refcount) > 0);
 482         LASSERT(lp->lp_rtr_refcount > 0);
 483
 484         /* lnet_net_lock must be exclusively locked */
 485         lp->lp_rtr_refcount--;
 486         if (lp->lp_rtr_refcount == 0) {
 487                 LASSERT(list_empty(&lp->lp_routes));
 488
 489                 list_del(&lp->lp_rtr_list);
 490                 /* decref for the_lnet.ln_routers */
 491                 lnet_peer_decref_locked(lp);
 492                 the_lnet.ln_routers_version++;
 493         }
 494 }
 495
 496 struct lnet_remotenet *
 497 lnet_find_rnet_locked(__u32 net)
 498 {
 499         struct lnet_remotenet *rnet;
 500         struct list_head *tmp;
 501         struct list_head *rn_list;
 502
 503         LASSERT(the_lnet.ln_state == LNET_STATE_RUNNING);
 504
 505         rn_list = lnet_net2rnethash(net);
 506         list_for_each(tmp, rn_list) {
 507                 rnet = list_entry(tmp, struct lnet_remotenet, lrn_list);
 508
 509                 if (rnet->lrn_net == net)
 510                         return rnet;
 511         }
 512         return NULL;
 513 }
 514
 515 static void lnet_shuffle_seed(void)
 516 {
 517         static int seeded;
 518         struct lnet_ni *ni = NULL;
 519
 520         if (seeded)
 521                 return;
 522
 523         /* Nodes with small feet have little entropy
 524          * the NID for this node gives the most entropy in the low bits */
 525         while ((ni = lnet_get_next_ni_locked(NULL, ni)))
 526                 add_device_randomness(&ni->ni_nid, sizeof(ni->ni_nid));
 527
 528         seeded = 1;
 529 }
 530
 531 /* NB expects LNET_LOCK held */
 532 static void
 533 lnet_add_route_to_rnet(struct lnet_remotenet *rnet, struct lnet_route *route)
 534 {
 535         struct lnet_peer_net *lpn;
 536         unsigned int offset = 0;
 537         unsigned int len = 0;
 538         struct list_head *e;
 539
 540         lnet_shuffle_seed();
 541
 542         list_for_each(e, &rnet->lrn_routes)
 543                 len++;
 544
 545         /*
 546          * Randomly adding routes to the list is done to ensure that when
 547          * different nodes are using the same list of routers, they end up
 548          * preferring different routers.
 549          */
 550         offset = prandom_u32_max(len + 1);
 551         list_for_each(e, &rnet->lrn_routes) {
 552                 if (offset == 0)
 553                         break;
 554                 offset--;
 555         }
 556         list_add(&route->lr_list, e);
 557         /*
 558          * force a router check on the gateway to make sure the route is
 559          * alive
 560          */
 561         list_for_each_entry(lpn, &route->lr_gateway->lp_peer_nets,
 562                             lpn_peer_nets) {
 563                 lpn->lpn_rtrcheck_timestamp = 0;
 564         }
 565
 566         the_lnet.ln_remote_nets_version++;
 567
 568         /* add the route on the gateway list */
 569         list_add(&route->lr_gwlist, &route->lr_gateway->lp_routes);
 570
 571         /* take a router reference count on the gateway */
 572         lnet_rtr_addref_locked(route->lr_gateway);
 573 }
 574
 575 int
 576 lnet_add_route(__u32 net, __u32 hops, lnet_nid_t gateway,
 577                __u32 priority, __u32 sensitivity)
 578 {
 579         struct list_head *route_entry;
 580         struct lnet_remotenet *rnet;
 581         struct lnet_remotenet *rnet2;
 582         struct lnet_route *route;
 583         struct lnet_peer_ni *lpni;
 584         struct lnet_peer *gw;
 585         int add_route;
 586         int rc;
 587
 588         CDEBUG(D_NET, "Add route: remote net %s hops %d priority %u gw %s\n",
 589                libcfs_net2str(net), hops, priority, libcfs_nid2str(gateway));
 590
 591         if (gateway == LNET_NID_ANY ||
 592             LNET_NETTYP(LNET_NIDNET(gateway)) == LOLND ||
 593             net == LNET_NIDNET(LNET_NID_ANY) ||
 594             LNET_NETTYP(net) == LOLND ||
 595             LNET_NIDNET(gateway) == net ||
 596             (hops != LNET_UNDEFINED_HOPS && (hops < 1 || hops > 255)))
 597                 return -EINVAL;
 598
 599         /* it's a local network */
 600         if (lnet_islocalnet(net))
 601                 return -EEXIST;
 602
 603         if (!lnet_islocalnet(LNET_NIDNET(gateway))) {
 604                 CERROR("Cannot add route with gateway %s. There is no local interface configured on LNet %s\n",
 605                        libcfs_nid2str(gateway),
 606                        libcfs_net2str(LNET_NIDNET(gateway)));
 607                 return -EHOSTUNREACH;
 608         }
 609
 610         /* Assume net, route, all new */
 611         LIBCFS_ALLOC(route, sizeof(*route));
 612         LIBCFS_ALLOC(rnet, sizeof(*rnet));
 613         if (route == NULL || rnet == NULL) {
 614                 CERROR("Out of memory creating route %s %d %s\n",
 615                        libcfs_net2str(net), hops, libcfs_nid2str(gateway));
 616                 if (route != NULL)
 617                         LIBCFS_FREE(route, sizeof(*route));
 618                 if (rnet != NULL)
 619                         LIBCFS_FREE(rnet, sizeof(*rnet));
 620                 return -ENOMEM;
 621         }
 622
 623         INIT_LIST_HEAD(&rnet->lrn_routes);
 624         rnet->lrn_net = net;
 625         /* store the local and remote net that the route represents */
 626         route->lr_lnet = LNET_NIDNET(gateway);
 627         route->lr_net = net;
 628         route->lr_nid = gateway;
 629         route->lr_priority = priority;
 630         route->lr_hops = hops;
 631
 632         lnet_net_lock(LNET_LOCK_EX);
 633
 634         /*
 635          * lnet_nid2peerni_ex() grabs a ref on the lpni. We will need to
 636          * lose that once we're done
 637          */
 638         lpni = lnet_nid2peerni_ex(gateway, LNET_LOCK_EX);
 639         if (IS_ERR(lpni)) {
 640                 lnet_net_unlock(LNET_LOCK_EX);
 641
 642                 LIBCFS_FREE(route, sizeof(*route));
 643                 LIBCFS_FREE(rnet, sizeof(*rnet));
 644
 645                 rc = PTR_ERR(lpni);
 646                 CERROR("Error %d creating route %s %d %s\n", rc,
 647                         libcfs_net2str(net), hops,
 648                         libcfs_nid2str(gateway));
 649                 return rc;
 650         }
 651
 652         LASSERT(lpni->lpni_peer_net && lpni->lpni_peer_net->lpn_peer);
 653         gw = lpni->lpni_peer_net->lpn_peer;
 654
 655         route->lr_gateway = gw;
 656
 657         rnet2 = lnet_find_rnet_locked(net);
 658         if (rnet2 == NULL) {
 659                 /* new network */
 660                 list_add_tail(&rnet->lrn_list, lnet_net2rnethash(net));
 661                 rnet2 = rnet;
 662         }
 663
 664         /* Search for a duplicate route (it's a NOOP if it is) */
 665         add_route = 1;
 666         list_for_each(route_entry, &rnet2->lrn_routes) {
 667                 struct lnet_route *route2;
 668
 669                 route2 = list_entry(route_entry, struct lnet_route, lr_list);
 670                 if (route2->lr_gateway == route->lr_gateway) {
 671                         add_route = 0;
 672                         break;
 673                 }
 674
 675                 /* our lookups must be true */
 676                 LASSERT(route2->lr_gateway->lp_primary_nid != gateway);
 677         }
 678
 679         /*
 680          * It is possible to add multiple routes through the same peer,
 681          * but it'll be using a different NID of that peer. When the
 682          * gateway is discovered, discovery will consolidate the different
 683          * peers into one peer. In this case the discovery code will have
 684          * to move the routes from the peer that's being deleted to the
 685          * consolidated peer lp_routes list
 686          */
 687         if (add_route) {
 688                 gw->lp_health_sensitivity = sensitivity;
 689                 lnet_add_route_to_rnet(rnet2, route);
 690                 if (lnet_peer_discovery_disabled)
 691                         CWARN("Consider turning discovery on to enable full "
 692                               "Multi-Rail routing functionality\n");
 693         }
 694
 695         /*
 696          * get rid of the reference on the lpni.
 697          */
 698         lnet_peer_ni_decref_locked(lpni);
 699         lnet_net_unlock(LNET_LOCK_EX);
 700
 701         rc = 0;
 702
 703         if (!add_route) {
 704                 rc = -EEXIST;
 705                 LIBCFS_FREE(route, sizeof(*route));
 706         }
 707
 708         if (rnet != rnet2)
 709                 LIBCFS_FREE(rnet, sizeof(*rnet));
 710
 711         /* kick start the monitor thread to handle the added route */
 712         complete(&the_lnet.ln_mt_wait_complete);
 713
 714         return rc;
 715 }
 716
 717 static void
 718 lnet_del_route_from_rnet(lnet_nid_t gw_nid, struct list_head *route_list,
 719                          struct list_head *zombies)
 720 {
 721         struct lnet_peer *gateway;
 722         struct lnet_route *route;
 723         struct lnet_route *tmp;
 724
 725         list_for_each_entry_safe(route, tmp, route_list, lr_list) {
 726                 gateway = route->lr_gateway;
 727                 if (gw_nid != LNET_NID_ANY &&
 728                     gw_nid != gateway->lp_primary_nid)
 729                         continue;
 730
 731                 /*
 732                  * move to zombie to delete outside the lock
 733                  * Note that this function is called with the
 734                  * ln_api_mutex held as well as the exclusive net
 735                  * lock. Adding to the remote net list happens
 736                  * under the same conditions. Same goes for the
 737                  * gateway router list
 738                  */
 739                 list_move(&route->lr_list, zombies);
 740                 the_lnet.ln_remote_nets_version++;
 741
 742                 list_del(&route->lr_gwlist);
 743                 lnet_rtr_decref_locked(gateway);
 744         }
 745 }
 746
 747 int
 748 lnet_del_route(__u32 net, lnet_nid_t gw_nid)
 749 {
 750         LIST_HEAD(rnet_zombies);
 751         struct lnet_remotenet *rnet;
 752         struct lnet_remotenet *tmp;
 753         struct list_head *rn_list;
 754         struct lnet_peer_ni *lpni;
 755         struct lnet_route *route;
 756         LIST_HEAD(zombies);
 757         struct lnet_peer *lp = NULL;
 758         int i = 0;
 759
 760         CDEBUG(D_NET, "Del route: net %s : gw %s\n",
 761                libcfs_net2str(net), libcfs_nid2str(gw_nid));
 762
 763         /* NB Caller may specify either all routes via the given gateway
 764          * or a specific route entry actual NIDs) */
 765
 766         lnet_net_lock(LNET_LOCK_EX);
 767
 768         lpni = lnet_find_peer_ni_locked(gw_nid);
 769         if (lpni) {
 770                 lp = lpni->lpni_peer_net->lpn_peer;
 771                 LASSERT(lp);
 772                 gw_nid = lp->lp_primary_nid;
 773                 lnet_peer_ni_decref_locked(lpni);
 774         }
 775
 776         if (net != LNET_NIDNET(LNET_NID_ANY)) {
 777                 rnet = lnet_find_rnet_locked(net);
 778                 if (!rnet) {
 779                         lnet_net_unlock(LNET_LOCK_EX);
 780                         return -ENOENT;
 781                 }
 782                 lnet_del_route_from_rnet(gw_nid, &rnet->lrn_routes,
 783                                          &zombies);
 784                 if (list_empty(&rnet->lrn_routes))
 785                         list_move(&rnet->lrn_list, &rnet_zombies);
 786                 goto delete_zombies;
 787         }
 788
 789         for (i = 0; i < LNET_REMOTE_NETS_HASH_SIZE; i++) {
 790                 rn_list = &the_lnet.ln_remote_nets_hash[i];
 791
 792                 list_for_each_entry_safe(rnet, tmp, rn_list, lrn_list) {
 793                         lnet_del_route_from_rnet(gw_nid, &rnet->lrn_routes,
 794                                                  &zombies);
 795                         if (list_empty(&rnet->lrn_routes))
 796                                 list_move(&rnet->lrn_list, &rnet_zombies);
 797                 }
 798         }
 799
 800 delete_zombies:
 801         /*
 802          * check if there are any routes remaining on the gateway
 803          * If there are no more routes make sure to set the peer's
 804          * lp_disc_net_id to 0 (invalid), in case we add more routes in
 805          * the future on that gateway, then we start our discovery process
 806          * from scratch
 807          */
 808         if (lpni) {
 809                 if (list_empty(&lp->lp_routes))
 810                         lp->lp_disc_net_id = 0;
 811         }
 812
 813         lnet_net_unlock(LNET_LOCK_EX);
 814
 815         while (!list_empty(&zombies)) {
 816                 route = list_first_entry(&zombies, struct lnet_route, lr_list);
 817                 list_del(&route->lr_list);
 818                 LIBCFS_FREE(route, sizeof(*route));
 819         }
 820
 821         while (!list_empty(&rnet_zombies)) {
 822                 rnet = list_first_entry(&rnet_zombies, struct lnet_remotenet,
 823                                         lrn_list);
 824                 list_del(&rnet->lrn_list);
 825                 LIBCFS_FREE(rnet, sizeof(*rnet));
 826         }
 827
 828         return 0;
 829 }
 830
 831 void
 832 lnet_destroy_routes (void)
 833 {
 834         lnet_del_route(LNET_NIDNET(LNET_NID_ANY), LNET_NID_ANY);
 835 }
 836
 837 int lnet_get_rtr_pool_cfg(int cpt, struct lnet_ioctl_pool_cfg *pool_cfg)
 838 {
 839         struct lnet_rtrbufpool *rbp;
 840         int i, rc = -ENOENT, j;
 841
 842         if (the_lnet.ln_rtrpools == NULL)
 843                 return rc;
 844
 845
 846         cfs_percpt_for_each(rbp, i, the_lnet.ln_rtrpools) {
 847                 if (i != cpt)
 848                         continue;
 849
 850                 lnet_net_lock(i);
 851                 for (j = 0; j < LNET_NRBPOOLS; j++) {
 852                         pool_cfg->pl_pools[j].pl_npages = rbp[j].rbp_npages;
 853                         pool_cfg->pl_pools[j].pl_nbuffers = rbp[j].rbp_nbuffers;
 854                         pool_cfg->pl_pools[j].pl_credits = rbp[j].rbp_credits;
 855                         pool_cfg->pl_pools[j].pl_mincredits = rbp[j].rbp_mincredits;
 856                 }
 857                 lnet_net_unlock(i);
 858                 rc = 0;
 859                 break;
 860         }
 861
 862         lnet_net_lock(LNET_LOCK_EX);
 863         pool_cfg->pl_routing = the_lnet.ln_routing;
 864         lnet_net_unlock(LNET_LOCK_EX);
 865
 866         return rc;
 867 }
 868
 869 int
 870 lnet_get_route(int idx, __u32 *net, __u32 *hops,
 871                lnet_nid_t *gateway, __u32 *alive, __u32 *priority, __u32 *sensitivity)
 872 {
 873         struct lnet_remotenet *rnet;
 874         struct list_head *rn_list;
 875         struct lnet_route *route;
 876         struct list_head *e1;
 877         struct list_head *e2;
 878         int cpt;
 879         int i;
 880
 881         cpt = lnet_net_lock_current();
 882
 883         for (i = 0; i < LNET_REMOTE_NETS_HASH_SIZE; i++) {
 884                 rn_list = &the_lnet.ln_remote_nets_hash[i];
 885                 list_for_each(e1, rn_list) {
 886                         rnet = list_entry(e1, struct lnet_remotenet, lrn_list);
 887
 888                         list_for_each(e2, &rnet->lrn_routes) {
 889                                 route = list_entry(e2, struct lnet_route,
 890                                                    lr_list);
 891
 892                                 if (idx-- == 0) {
 893                                         *net      = rnet->lrn_net;
 894                                         *gateway  = route->lr_nid;
 895                                         *hops     = route->lr_hops;
 896                                         *priority = route->lr_priority;
 897                                         *sensitivity = route->lr_gateway->
 898                                                 lp_health_sensitivity;
 899                                         *alive    = lnet_is_route_alive(route);
 900                                         lnet_net_unlock(cpt);
 901                                         return 0;
 902                                 }
 903                         }
 904                 }
 905         }
 906
 907         lnet_net_unlock(cpt);
 908         return -ENOENT;
 909 }
 910
 911 static void
 912 lnet_wait_known_routerstate(void)
 913 {
 914         struct lnet_peer *rtr;
 915         struct list_head *entry;
 916         int all_known;
 917
 918         LASSERT(the_lnet.ln_mt_state == LNET_MT_STATE_RUNNING);
 919
 920         for (;;) {
 921                 int cpt = lnet_net_lock_current();
 922
 923                 all_known = 1;
 924                 list_for_each(entry, &the_lnet.ln_routers) {
 925                         rtr = list_entry(entry, struct lnet_peer,
 926                                          lp_rtr_list);
 927
 928                         spin_lock(&rtr->lp_lock);
 929
 930                         if ((rtr->lp_state & LNET_PEER_RTR_DISCOVERED) == 0) {
 931                                 all_known = 0;
 932                                 spin_unlock(&rtr->lp_lock);
 933                                 break;
 934                         }
 935                         spin_unlock(&rtr->lp_lock);
 936                 }
 937
 938                 lnet_net_unlock(cpt);
 939
 940                 if (all_known)
 941                         return;
 942
 943                 set_current_state(TASK_UNINTERRUPTIBLE);
 944                 schedule_timeout(cfs_time_seconds(1));
 945         }
 946 }
 947
 948 static inline bool
 949 lnet_net_set_status_locked(struct lnet_net *net, __u32 status)
 950 {
 951         struct lnet_ni *ni;
 952         bool update = false;
 953
 954         list_for_each_entry(ni, &net->net_ni_list, ni_netlist) {
 955                 lnet_ni_lock(ni);
 956                 if (ni->ni_status &&
 957                     ni->ni_status->ns_status != status) {
 958                     ni->ni_status->ns_status = status;
 959                     update = true;
 960                 }
 961                 lnet_ni_unlock(ni);
 962         }
 963
 964         return update;
 965 }
 966
 967 static bool
 968 lnet_update_ni_status_locked(void)
 969 {
 970         struct lnet_net *net;
 971         bool push = false;
 972         time64_t now;
 973         time64_t timeout;
 974
 975         LASSERT(the_lnet.ln_routing);
 976
 977         timeout = router_ping_timeout + alive_router_check_interval;
 978
 979         now = ktime_get_real_seconds();
 980         list_for_each_entry(net, &the_lnet.ln_nets, net_list) {
 981                 if (net->net_lnd->lnd_type == LOLND)
 982                         continue;
 983
 984                 if (now < net->net_last_alive + timeout)
 985                         continue;
 986
 987                 spin_lock(&net->net_lock);
 988                 /* re-check with lock */
 989                 if (now < net->net_last_alive + timeout) {
 990                         spin_unlock(&net->net_lock);
 991                         continue;
 992                 }
 993                 spin_unlock(&net->net_lock);
 994
 995                 /*
 996                  * if the net didn't receive any traffic for past the
 997                  * timeout on any of its constituent NIs, then mark all
 998                  * the NIs down.
 999                  */
1000                 push = lnet_net_set_status_locked(net, LNET_NI_STATUS_DOWN);
1001         }
1002
1003         return push;
1004 }
1005
1006 void lnet_wait_router_start(void)
1007 {
1008         if (check_routers_before_use) {
1009                 /* Note that a helpful side-effect of pinging all known routers
1010                  * at startup is that it makes them drop stale connections they
1011                  * may have to a previous instance of me. */
1012                 lnet_wait_known_routerstate();
1013         }
1014 }
1015
1016 /*
1017  * This function is called from the monitor thread to check if there are
1018  * any active routers that need to be checked.
1019  */
1020 inline bool
1021 lnet_router_checker_active(void)
1022 {
1023         /* Router Checker thread needs to run when routing is enabled in
1024          * order to call lnet_update_ni_status_locked() */
1025         if (the_lnet.ln_routing)
1026                 return true;
1027
1028         return !list_empty(&the_lnet.ln_routers) &&
1029                 alive_router_check_interval > 0;
1030 }
1031
1032 void
1033 lnet_check_routers(void)
1034 {
1035         struct lnet_peer_net *first_lpn = NULL;
1036         struct lnet_peer_net *lpn;
1037         struct lnet_peer_ni *lpni;
1038         struct list_head *entry;
1039         struct lnet_peer *rtr;
1040         bool push = false;
1041         bool found_lpn;
1042         __u64 version;
1043         __u32 net_id;
1044         time64_t now;
1045         int cpt;
1046         int rc;
1047
1048         cpt = lnet_net_lock_current();
1049 rescan:
1050         version = the_lnet.ln_routers_version;
1051
1052         list_for_each(entry, &the_lnet.ln_routers) {
1053                 rtr = list_entry(entry, struct lnet_peer,
1054                                  lp_rtr_list);
1055
1056                 now = ktime_get_real_seconds();
1057
1058                 /*
1059                  * only discover the router if we've passed
1060                  * alive_router_check_interval seconds. Some of the router
1061                  * interfaces could be down and in that case they would be
1062                  * undergoing recovery separately from this discovery.
1063                  */
1064                 /* find next peer net which is also local */
1065                 net_id = rtr->lp_disc_net_id;
1066                 do {
1067                         lpn = lnet_get_next_peer_net_locked(rtr, net_id);
1068                         if (!lpn) {
1069                                 CERROR("gateway %s has no networks\n",
1070                                 libcfs_nid2str(rtr->lp_primary_nid));
1071                                 break;
1072                         }
1073                         if (first_lpn == lpn)
1074                                 break;
1075                         if (!first_lpn)
1076                                 first_lpn = lpn;
1077                         found_lpn = lnet_islocalnet_locked(lpn->lpn_net_id);
1078                         net_id = lpn->lpn_net_id;
1079                 } while (!found_lpn);
1080
1081                 if (!found_lpn || !lpn) {
1082                         CERROR("no local network found for gateway %s\n",
1083                                libcfs_nid2str(rtr->lp_primary_nid));
1084                         continue;
1085                 }
1086
1087                 if (now - lpn->lpn_rtrcheck_timestamp <
1088                     alive_router_check_interval / lnet_current_net_count)
1089                        continue;
1090
1091                 /*
1092                  * If we're currently discovering the peer then don't
1093                  * issue another discovery
1094                  */
1095                 spin_lock(&rtr->lp_lock);
1096                 if (rtr->lp_state & LNET_PEER_RTR_DISCOVERY) {
1097                         spin_unlock(&rtr->lp_lock);
1098                         continue;
1099                 }
1100                 /* make sure we actively discover the router */
1101                 rtr->lp_state &= ~LNET_PEER_NIDS_UPTODATE;
1102                 rtr->lp_state |= LNET_PEER_RTR_DISCOVERY;
1103                 spin_unlock(&rtr->lp_lock);
1104
1105                 /* find the peer_ni associated with the primary NID */
1106                 lpni = lnet_peer_get_ni_locked(rtr, rtr->lp_primary_nid);
1107                 if (!lpni) {
1108                         CDEBUG(D_NET, "Expected to find an lpni for %s, but non found\n",
1109                                libcfs_nid2str(rtr->lp_primary_nid));
1110                         continue;
1111                 }
1112                 lnet_peer_ni_addref_locked(lpni);
1113
1114                 /* specify the net to use */
1115                 rtr->lp_disc_net_id = lpn->lpn_net_id;
1116
1117                 /* discover the router */
1118                 CDEBUG(D_NET, "discover %s, cpt = %d\n",
1119                        libcfs_nid2str(lpni->lpni_nid), cpt);
1120                 rc = lnet_discover_peer_locked(lpni, cpt, false);
1121
1122                 /* decrement ref count acquired by find_peer_ni_locked() */
1123                 lnet_peer_ni_decref_locked(lpni);
1124
1125                 if (!rc)
1126                         lpn->lpn_rtrcheck_timestamp = now;
1127                 else
1128                         CERROR("Failed to discover router %s\n",
1129                                libcfs_nid2str(rtr->lp_primary_nid));
1130
1131                 /* NB dropped lock */
1132                 if (version != the_lnet.ln_routers_version) {
1133                         /* the routers list has changed */
1134                         goto rescan;
1135                 }
1136         }
1137
1138         if (the_lnet.ln_routing)
1139                 push = lnet_update_ni_status_locked();
1140
1141         lnet_net_unlock(cpt);
1142
1143         /* if the status of the ni changed update the peers */
1144         if (push)
1145                 lnet_push_update_to_peers(1);
1146 }
1147
1148 void
1149 lnet_destroy_rtrbuf(struct lnet_rtrbuf *rb, int npages)
1150 {
1151         int sz = offsetof(struct lnet_rtrbuf, rb_kiov[npages]);
1152
1153         while (--npages >= 0)
1154                 __free_page(rb->rb_kiov[npages].kiov_page);
1155
1156         LIBCFS_FREE(rb, sz);
1157 }
1158
1159 static struct lnet_rtrbuf *
1160 lnet_new_rtrbuf(struct lnet_rtrbufpool *rbp, int cpt)
1161 {
1162         int            npages = rbp->rbp_npages;
1163         int            sz = offsetof(struct lnet_rtrbuf, rb_kiov[npages]);
1164         struct page   *page;
1165         struct lnet_rtrbuf *rb;
1166         int            i;
1167
1168         LIBCFS_CPT_ALLOC(rb, lnet_cpt_table(), cpt, sz);
1169         if (rb == NULL)
1170                 return NULL;
1171
1172         rb->rb_pool = rbp;
1173
1174         for (i = 0; i < npages; i++) {
1175                 page = cfs_page_cpt_alloc(lnet_cpt_table(), cpt,
1176                                           GFP_KERNEL | __GFP_ZERO);
1177                 if (page == NULL) {
1178                         while (--i >= 0)
1179                                 __free_page(rb->rb_kiov[i].kiov_page);
1180
1181                         LIBCFS_FREE(rb, sz);
1182                         return NULL;
1183                 }
1184
1185                 rb->rb_kiov[i].kiov_len = PAGE_SIZE;
1186                 rb->rb_kiov[i].kiov_offset = 0;
1187                 rb->rb_kiov[i].kiov_page = page;
1188         }
1189
1190         return rb;
1191 }
1192
1193 static void
1194 lnet_rtrpool_free_bufs(struct lnet_rtrbufpool *rbp, int cpt)
1195 {
1196         int npages = rbp->rbp_npages;
1197         struct lnet_rtrbuf *rb;
1198         LIST_HEAD(tmp);
1199
1200         if (rbp->rbp_nbuffers == 0) /* not initialized or already freed */
1201                 return;
1202
1203         lnet_net_lock(cpt);
1204         list_splice_init(&rbp->rbp_msgs, &tmp);
1205         lnet_drop_routed_msgs_locked(&tmp, cpt);
1206         list_splice_init(&rbp->rbp_bufs, &tmp);
1207         rbp->rbp_req_nbuffers = 0;
1208         rbp->rbp_nbuffers = rbp->rbp_credits = 0;
1209         rbp->rbp_mincredits = 0;
1210         lnet_net_unlock(cpt);
1211
1212         /* Free buffers on the free list. */
1213         while (!list_empty(&tmp)) {
1214                 rb = list_entry(tmp.next, struct lnet_rtrbuf, rb_list);
1215                 list_del(&rb->rb_list);
1216                 lnet_destroy_rtrbuf(rb, npages);
1217         }
1218 }
1219
1220 static int
1221 lnet_rtrpool_adjust_bufs(struct lnet_rtrbufpool *rbp, int nbufs, int cpt)
1222 {
1223         LIST_HEAD(rb_list);
1224         struct lnet_rtrbuf *rb;
1225         int             num_rb;
1226         int             num_buffers = 0;
1227         int             old_req_nbufs;
1228         int             npages = rbp->rbp_npages;
1229
1230         lnet_net_lock(cpt);
1231         /* If we are called for less buffers than already in the pool, we
1232          * just lower the req_nbuffers number and excess buffers will be
1233          * thrown away as they are returned to the free list.  Credits
1234          * then get adjusted as well.
1235          * If we already have enough buffers allocated to serve the
1236          * increase requested, then we can treat that the same way as we
1237          * do the decrease. */
1238         num_rb = nbufs - rbp->rbp_nbuffers;
1239         if (nbufs <= rbp->rbp_req_nbuffers || num_rb <= 0) {
1240                 rbp->rbp_req_nbuffers = nbufs;
1241                 lnet_net_unlock(cpt);
1242                 return 0;
1243         }
1244         /* store the older value of rbp_req_nbuffers and then set it to
1245          * the new request to prevent lnet_return_rx_credits_locked() from
1246          * freeing buffers that we need to keep around */
1247         old_req_nbufs = rbp->rbp_req_nbuffers;
1248         rbp->rbp_req_nbuffers = nbufs;
1249         lnet_net_unlock(cpt);
1250
1251         /* allocate the buffers on a local list first.  If all buffers are
1252          * allocated successfully then join this list to the rbp buffer
1253          * list.  If not then free all allocated buffers. */
1254         while (num_rb-- > 0) {
1255                 rb = lnet_new_rtrbuf(rbp, cpt);
1256                 if (rb == NULL) {
1257                         CERROR("Failed to allocate %d route bufs of %d pages\n",
1258                                nbufs, npages);
1259
1260                         lnet_net_lock(cpt);
1261                         rbp->rbp_req_nbuffers = old_req_nbufs;
1262                         lnet_net_unlock(cpt);
1263
1264                         goto failed;
1265                 }
1266
1267                 list_add(&rb->rb_list, &rb_list);
1268                 num_buffers++;
1269         }
1270
1271         lnet_net_lock(cpt);
1272
1273         list_splice_tail(&rb_list, &rbp->rbp_bufs);
1274         rbp->rbp_nbuffers += num_buffers;
1275         rbp->rbp_credits += num_buffers;
1276         rbp->rbp_mincredits = rbp->rbp_credits;
1277         /* We need to schedule blocked msg using the newly
1278          * added buffers. */
1279         while (!list_empty(&rbp->rbp_bufs) &&
1280                !list_empty(&rbp->rbp_msgs))
1281                 lnet_schedule_blocked_locked(rbp);
1282
1283         lnet_net_unlock(cpt);
1284
1285         return 0;
1286
1287 failed:
1288         while (!list_empty(&rb_list)) {
1289                 rb = list_entry(rb_list.next, struct lnet_rtrbuf, rb_list);
1290                 list_del(&rb->rb_list);
1291                 lnet_destroy_rtrbuf(rb, npages);
1292         }
1293
1294         return -ENOMEM;
1295 }
1296
1297 static void
1298 lnet_rtrpool_init(struct lnet_rtrbufpool *rbp, int npages)
1299 {
1300         INIT_LIST_HEAD(&rbp->rbp_msgs);
1301         INIT_LIST_HEAD(&rbp->rbp_bufs);
1302
1303         rbp->rbp_npages = npages;
1304         rbp->rbp_credits = 0;
1305         rbp->rbp_mincredits = 0;
1306 }
1307
1308 void
1309 lnet_rtrpools_free(int keep_pools)
1310 {
1311         struct lnet_rtrbufpool *rtrp;
1312         int               i;
1313
1314         if (the_lnet.ln_rtrpools == NULL) /* uninitialized or freed */
1315                 return;
1316
1317         cfs_percpt_for_each(rtrp, i, the_lnet.ln_rtrpools) {
1318                 lnet_rtrpool_free_bufs(&rtrp[LNET_TINY_BUF_IDX], i);
1319                 lnet_rtrpool_free_bufs(&rtrp[LNET_SMALL_BUF_IDX], i);
1320                 lnet_rtrpool_free_bufs(&rtrp[LNET_LARGE_BUF_IDX], i);
1321         }
1322
1323         if (!keep_pools) {
1324                 cfs_percpt_free(the_lnet.ln_rtrpools);
1325                 the_lnet.ln_rtrpools = NULL;
1326         }
1327 }
1328
1329 static int
1330 lnet_nrb_tiny_calculate(void)
1331 {
1332         int     nrbs = LNET_NRB_TINY;
1333
1334         if (tiny_router_buffers < 0) {
1335                 LCONSOLE_ERROR_MSG(0x10c,
1336                                    "tiny_router_buffers=%d invalid when "
1337                                    "routing enabled\n", tiny_router_buffers);
1338                 return -EINVAL;
1339         }
1340
1341         if (tiny_router_buffers > 0)
1342                 nrbs = tiny_router_buffers;
1343
1344         nrbs /= LNET_CPT_NUMBER;
1345         return max(nrbs, LNET_NRB_TINY_MIN);
1346 }
1347
1348 static int
1349 lnet_nrb_small_calculate(void)
1350 {
1351         int     nrbs = LNET_NRB_SMALL;
1352
1353         if (small_router_buffers < 0) {
1354                 LCONSOLE_ERROR_MSG(0x10c,
1355                                    "small_router_buffers=%d invalid when "
1356                                    "routing enabled\n", small_router_buffers);
1357                 return -EINVAL;
1358         }
1359
1360         if (small_router_buffers > 0)
1361                 nrbs = small_router_buffers;
1362
1363         nrbs /= LNET_CPT_NUMBER;
1364         return max(nrbs, LNET_NRB_SMALL_MIN);
1365 }
1366
1367 static int
1368 lnet_nrb_large_calculate(void)
1369 {
1370         int     nrbs = LNET_NRB_LARGE;
1371
1372         if (large_router_buffers < 0) {
1373                 LCONSOLE_ERROR_MSG(0x10c,
1374                                    "large_router_buffers=%d invalid when "
1375                                    "routing enabled\n", large_router_buffers);
1376                 return -EINVAL;
1377         }
1378
1379         if (large_router_buffers > 0)
1380                 nrbs = large_router_buffers;
1381
1382         nrbs /= LNET_CPT_NUMBER;
1383         return max(nrbs, LNET_NRB_LARGE_MIN);
1384 }
1385
1386 int
1387 lnet_rtrpools_alloc(int im_a_router)
1388 {
1389         struct lnet_rtrbufpool *rtrp;
1390         int     nrb_tiny;
1391         int     nrb_small;
1392         int     nrb_large;
1393         int     rc;
1394         int     i;
1395
1396         if (!strcmp(forwarding, "")) {
1397                 /* not set either way */
1398                 if (!im_a_router)
1399                         return 0;
1400         } else if (!strcmp(forwarding, "disabled")) {
1401                 /* explicitly disabled */
1402                 return 0;
1403         } else if (!strcmp(forwarding, "enabled")) {
1404                 /* explicitly enabled */
1405         } else {
1406                 LCONSOLE_ERROR_MSG(0x10b, "'forwarding' not set to either "
1407                                    "'enabled' or 'disabled'\n");
1408                 return -EINVAL;
1409         }
1410
1411         nrb_tiny = lnet_nrb_tiny_calculate();
1412         if (nrb_tiny < 0)
1413                 return -EINVAL;
1414
1415         nrb_small = lnet_nrb_small_calculate();
1416         if (nrb_small < 0)
1417                 return -EINVAL;
1418
1419         nrb_large = lnet_nrb_large_calculate();
1420         if (nrb_large < 0)
1421                 return -EINVAL;
1422
1423         the_lnet.ln_rtrpools = cfs_percpt_alloc(lnet_cpt_table(),
1424                                                 LNET_NRBPOOLS *
1425                                                 sizeof(struct lnet_rtrbufpool));
1426         if (the_lnet.ln_rtrpools == NULL) {
1427                 LCONSOLE_ERROR_MSG(0x10c,
1428                                    "Failed to initialize router buffe pool\n");
1429                 return -ENOMEM;
1430         }
1431
1432         cfs_percpt_for_each(rtrp, i, the_lnet.ln_rtrpools) {
1433                 lnet_rtrpool_init(&rtrp[LNET_TINY_BUF_IDX], 0);
1434                 rc = lnet_rtrpool_adjust_bufs(&rtrp[LNET_TINY_BUF_IDX],
1435                                               nrb_tiny, i);
1436                 if (rc != 0)
1437                         goto failed;
1438
1439                 lnet_rtrpool_init(&rtrp[LNET_SMALL_BUF_IDX],
1440                                   LNET_NRB_SMALL_PAGES);
1441                 rc = lnet_rtrpool_adjust_bufs(&rtrp[LNET_SMALL_BUF_IDX],
1442                                               nrb_small, i);
1443                 if (rc != 0)
1444                         goto failed;
1445
1446                 lnet_rtrpool_init(&rtrp[LNET_LARGE_BUF_IDX],
1447                                   LNET_NRB_LARGE_PAGES);
1448                 rc = lnet_rtrpool_adjust_bufs(&rtrp[LNET_LARGE_BUF_IDX],
1449                                               nrb_large, i);
1450                 if (rc != 0)
1451                         goto failed;
1452         }
1453
1454         lnet_net_lock(LNET_LOCK_EX);
1455         the_lnet.ln_routing = 1;
1456         lnet_net_unlock(LNET_LOCK_EX);
1457         complete(&the_lnet.ln_mt_wait_complete);
1458         return 0;
1459
1460  failed:
1461         lnet_rtrpools_free(0);
1462         return rc;
1463 }
1464
1465 static int
1466 lnet_rtrpools_adjust_helper(int tiny, int small, int large)
1467 {
1468         int nrb = 0;
1469         int rc = 0;
1470         int i;
1471         struct lnet_rtrbufpool *rtrp;
1472
1473         /* If the provided values for each buffer pool are different than the
1474          * configured values, we need to take action. */
1475         if (tiny >= 0) {
1476                 tiny_router_buffers = tiny;
1477                 nrb = lnet_nrb_tiny_calculate();
1478                 cfs_percpt_for_each(rtrp, i, the_lnet.ln_rtrpools) {
1479                         rc = lnet_rtrpool_adjust_bufs(&rtrp[LNET_TINY_BUF_IDX],
1480                                                       nrb, i);
1481                         if (rc != 0)
1482                                 return rc;
1483                 }
1484         }
1485         if (small >= 0) {
1486                 small_router_buffers = small;
1487                 nrb = lnet_nrb_small_calculate();
1488                 cfs_percpt_for_each(rtrp, i, the_lnet.ln_rtrpools) {
1489                         rc = lnet_rtrpool_adjust_bufs(&rtrp[LNET_SMALL_BUF_IDX],
1490                                                       nrb, i);
1491                         if (rc != 0)
1492                                 return rc;
1493                 }
1494         }
1495         if (large >= 0) {
1496                 large_router_buffers = large;
1497                 nrb = lnet_nrb_large_calculate();
1498                 cfs_percpt_for_each(rtrp, i, the_lnet.ln_rtrpools) {
1499                         rc = lnet_rtrpool_adjust_bufs(&rtrp[LNET_LARGE_BUF_IDX],
1500                                                       nrb, i);
1501                         if (rc != 0)
1502                                 return rc;
1503                 }
1504         }
1505
1506         return 0;
1507 }
1508
1509 int
1510 lnet_rtrpools_adjust(int tiny, int small, int large)
1511 {
1512         /* this function doesn't revert the changes if adding new buffers
1513          * failed.  It's up to the user space caller to revert the
1514          * changes. */
1515
1516         if (!the_lnet.ln_routing)
1517                 return 0;
1518
1519         return lnet_rtrpools_adjust_helper(tiny, small, large);
1520 }
1521
1522 int
1523 lnet_rtrpools_enable(void)
1524 {
1525         int rc = 0;
1526
1527         if (the_lnet.ln_routing)
1528                 return 0;
1529
1530         if (the_lnet.ln_rtrpools == NULL)
1531                 /* If routing is turned off, and we have never
1532                  * initialized the pools before, just call the
1533                  * standard buffer pool allocation routine as
1534                  * if we are just configuring this for the first
1535                  * time. */
1536                 rc = lnet_rtrpools_alloc(1);
1537         else
1538                 rc = lnet_rtrpools_adjust_helper(0, 0, 0);
1539         if (rc != 0)
1540                 return rc;
1541
1542         lnet_net_lock(LNET_LOCK_EX);
1543         the_lnet.ln_routing = 1;
1544
1545         the_lnet.ln_ping_target->pb_info.pi_features &=
1546                 ~LNET_PING_FEAT_RTE_DISABLED;
1547         lnet_net_unlock(LNET_LOCK_EX);
1548
1549         if (lnet_peer_discovery_disabled)
1550                 CWARN("Consider turning discovery on to enable full "
1551                       "Multi-Rail routing functionality\n");
1552
1553         return rc;
1554 }
1555
1556 void
1557 lnet_rtrpools_disable(void)
1558 {
1559         if (!the_lnet.ln_routing)
1560                 return;
1561
1562         lnet_net_lock(LNET_LOCK_EX);
1563         the_lnet.ln_routing = 0;
1564         the_lnet.ln_ping_target->pb_info.pi_features |=
1565                 LNET_PING_FEAT_RTE_DISABLED;
1566
1567         tiny_router_buffers = 0;
1568         small_router_buffers = 0;
1569         large_router_buffers = 0;
1570         lnet_net_unlock(LNET_LOCK_EX);
1571         lnet_rtrpools_free(1);
1572 }
1573
1574 static inline void
1575 lnet_notify_peer_down(struct lnet_ni *ni, lnet_nid_t nid)
1576 {
1577         if (ni->ni_net->net_lnd->lnd_notify_peer_down != NULL)
1578                 (ni->ni_net->net_lnd->lnd_notify_peer_down)(nid);
1579 }
1580
1581 /*
1582  * ni: local NI used to communicate with the peer
1583  * nid: peer NID
1584  * alive: true if peer is alive, false otherwise
1585  * reset: reset health value. This is requested by the LND.
1586  * when: notificaiton time.
1587  */
1588 int
1589 lnet_notify(struct lnet_ni *ni, lnet_nid_t nid, bool alive, bool reset,
1590             time64_t when)
1591 {
1592         struct lnet_peer_ni *lpni = NULL;
1593         struct lnet_route *route;
1594         struct lnet_peer *lp;
1595         time64_t now = ktime_get_seconds();
1596         int cpt;
1597
1598         LASSERT (!in_interrupt ());
1599
1600         CDEBUG (D_NET, "%s notifying %s: %s\n",
1601                 (ni == NULL) ? "userspace" : libcfs_nid2str(ni->ni_nid),
1602                 libcfs_nid2str(nid),
1603                 alive ? "up" : "down");
1604
1605         if (ni != NULL &&
1606             LNET_NIDNET(ni->ni_nid) != LNET_NIDNET(nid)) {
1607                 CWARN("Ignoring notification of %s %s by %s (different net)\n",
1608                       libcfs_nid2str(nid), alive ? "birth" : "death",
1609                       libcfs_nid2str(ni->ni_nid));
1610                 return -EINVAL;
1611         }
1612
1613         /* can't do predictions... */
1614         if (when > now) {
1615                 CWARN("Ignoring prediction from %s of %s %s "
1616                       "%lld seconds in the future\n",
1617                       (ni == NULL) ? "userspace" : libcfs_nid2str(ni->ni_nid),
1618                       libcfs_nid2str(nid), alive ? "up" : "down", when - now);
1619                 return -EINVAL;
1620         }
1621
1622         if (ni != NULL && !alive &&             /* LND telling me she's down */
1623             !auto_down) {                       /* auto-down disabled */
1624                 CDEBUG(D_NET, "Auto-down disabled\n");
1625                 return 0;
1626         }
1627
1628         /* must lock 0 since this is used for synchronization */
1629         lnet_net_lock(0);
1630
1631         if (the_lnet.ln_state != LNET_STATE_RUNNING) {
1632                 lnet_net_unlock(0);
1633                 return -ESHUTDOWN;
1634         }
1635
1636         lpni = lnet_find_peer_ni_locked(nid);
1637         if (lpni == NULL) {
1638                 /* nid not found */
1639                 lnet_net_unlock(0);
1640                 CDEBUG(D_NET, "%s not found\n", libcfs_nid2str(nid));
1641                 return 0;
1642         }
1643
1644         if (alive) {
1645                 if (reset)
1646                         lnet_set_healthv(&lpni->lpni_healthv,
1647                                          LNET_MAX_HEALTH_VALUE);
1648                 else
1649                         lnet_inc_healthv(&lpni->lpni_healthv);
1650         } else {
1651                 lnet_handle_remote_failure_locked(lpni);
1652         }
1653
1654         /* recalculate aliveness */
1655         alive = lnet_is_peer_ni_alive(lpni);
1656         lnet_net_unlock(0);
1657
1658         if (ni != NULL && !alive)
1659                 lnet_notify_peer_down(ni, lpni->lpni_nid);
1660
1661         cpt = lpni->lpni_cpt;
1662         lnet_net_lock(cpt);
1663         lnet_peer_ni_decref_locked(lpni);
1664         if (lpni && lpni->lpni_peer_net && lpni->lpni_peer_net->lpn_peer) {
1665                 lp = lpni->lpni_peer_net->lpn_peer;
1666                 lp->lp_alive = alive;
1667                 list_for_each_entry(route, &lp->lp_routes, lr_gwlist)
1668                         lnet_set_route_aliveness(route, alive);
1669         }
1670         lnet_net_unlock(cpt);
1671
1672         return 0;
1673 }
1674 EXPORT_SYMBOL(lnet_notify);