kernel/drivers/staging/lustre/lnet/lnet/router.c

   1 /*
   2  * Copyright (c) 2007, 2010, Oracle and/or its affiliates. All rights reserved.
   3  *
   4  * Copyright (c) 2011, 2012, Intel Corporation.
   5  *
   6  *   This file is part of Portals
   7  *   http://sourceforge.net/projects/sandiaportals/
   8  *
   9  *   Portals is free software; you can redistribute it and/or
  10  *   modify it under the terms of version 2 of the GNU General Public
  11  *   License as published by the Free Software Foundation.
  12  *
  13  *   Portals is distributed in the hope that it will be useful,
  14  *   but WITHOUT ANY WARRANTY; without even the implied warranty of
  15  *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  16  *   GNU General Public License for more details.
  17  *
  18  *   You should have received a copy of the GNU General Public License
  19  *   along with Portals; if not, write to the Free Software
  20  *   Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
  21  *
  22  */
  23
  24 #define DEBUG_SUBSYSTEM S_LNET
  25 #include "../../include/linux/lnet/lib-lnet.h"
  26
  27 #define LNET_NRB_TINY_MIN       512     /* min value for each CPT */
  28 #define LNET_NRB_TINY           (LNET_NRB_TINY_MIN * 4)
  29 #define LNET_NRB_SMALL_MIN      4096    /* min value for each CPT */
  30 #define LNET_NRB_SMALL          (LNET_NRB_SMALL_MIN * 4)
  31 #define LNET_NRB_LARGE_MIN      256     /* min value for each CPT */
  32 #define LNET_NRB_LARGE          (LNET_NRB_LARGE_MIN * 4)
  33
  34 static char *forwarding = "";
  35 module_param(forwarding, charp, 0444);
  36 MODULE_PARM_DESC(forwarding, "Explicitly enable/disable forwarding between networks");
  37
  38 static int tiny_router_buffers;
  39 module_param(tiny_router_buffers, int, 0444);
  40 MODULE_PARM_DESC(tiny_router_buffers, "# of 0 payload messages to buffer in the router");
  41 static int small_router_buffers;
  42 module_param(small_router_buffers, int, 0444);
  43 MODULE_PARM_DESC(small_router_buffers, "# of small (1 page) messages to buffer in the router");
  44 static int large_router_buffers;
  45 module_param(large_router_buffers, int, 0444);
  46 MODULE_PARM_DESC(large_router_buffers, "# of large messages to buffer in the router");
  47 static int peer_buffer_credits;
  48 module_param(peer_buffer_credits, int, 0444);
  49 MODULE_PARM_DESC(peer_buffer_credits, "# router buffer credits per peer");
  50
  51 static int auto_down = 1;
  52 module_param(auto_down, int, 0444);
  53 MODULE_PARM_DESC(auto_down, "Automatically mark peers down on comms error");
  54
  55 int
  56 lnet_peer_buffer_credits(lnet_ni_t *ni)
  57 {
  58         /* NI option overrides LNet default */
  59         if (ni->ni_peerrtrcredits > 0)
  60                 return ni->ni_peerrtrcredits;
  61         if (peer_buffer_credits > 0)
  62                 return peer_buffer_credits;
  63
  64         /* As an approximation, allow this peer the same number of router
  65          * buffers as it is allowed outstanding sends */
  66         return ni->ni_peertxcredits;
  67 }
  68
  69 /* forward ref's */
  70 static int lnet_router_checker(void *);
  71
  72 static int check_routers_before_use;
  73 module_param(check_routers_before_use, int, 0444);
  74 MODULE_PARM_DESC(check_routers_before_use, "Assume routers are down and ping them before use");
  75
  76 int avoid_asym_router_failure = 1;
  77 module_param(avoid_asym_router_failure, int, 0644);
  78 MODULE_PARM_DESC(avoid_asym_router_failure, "Avoid asymmetrical router failures (0 to disable)");
  79
  80 static int dead_router_check_interval = 60;
  81 module_param(dead_router_check_interval, int, 0644);
  82 MODULE_PARM_DESC(dead_router_check_interval, "Seconds between dead router health checks (<= 0 to disable)");
  83
  84 static int live_router_check_interval = 60;
  85 module_param(live_router_check_interval, int, 0644);
  86 MODULE_PARM_DESC(live_router_check_interval, "Seconds between live router health checks (<= 0 to disable)");
  87
  88 static int router_ping_timeout = 50;
  89 module_param(router_ping_timeout, int, 0644);
  90 MODULE_PARM_DESC(router_ping_timeout, "Seconds to wait for the reply to a router health query");
  91
  92 int
  93 lnet_peers_start_down(void)
  94 {
  95         return check_routers_before_use;
  96 }
  97
  98 void
  99 lnet_notify_locked(lnet_peer_t *lp, int notifylnd, int alive,
 100                    unsigned long when)
 101 {
 102         if (time_before(when, lp->lp_timestamp)) { /* out of date information */
 103                 CDEBUG(D_NET, "Out of date\n");
 104                 return;
 105         }
 106
 107         lp->lp_timestamp = when;                /* update timestamp */
 108         lp->lp_ping_deadline = 0;              /* disable ping timeout */
 109
 110         if (lp->lp_alive_count != 0 &&    /* got old news */
 111             (!lp->lp_alive) == (!alive)) {      /* new date for old news */
 112                 CDEBUG(D_NET, "Old news\n");
 113                 return;
 114         }
 115
 116         /* Flag that notification is outstanding */
 117
 118         lp->lp_alive_count++;
 119         lp->lp_alive = !(!alive);              /* 1 bit! */
 120         lp->lp_notify = 1;
 121         lp->lp_notifylnd |= notifylnd;
 122         if (lp->lp_alive)
 123                 lp->lp_ping_feats = LNET_PING_FEAT_INVAL; /* reset */
 124
 125         CDEBUG(D_NET, "set %s %d\n", libcfs_nid2str(lp->lp_nid), alive);
 126 }
 127
 128 static void
 129 lnet_ni_notify_locked(lnet_ni_t *ni, lnet_peer_t *lp)
 130 {
 131         int alive;
 132         int notifylnd;
 133
 134         /* Notify only in 1 thread at any time to ensure ordered notification.
 135          * NB individual events can be missed; the only guarantee is that you
 136          * always get the most recent news */
 137
 138         if (lp->lp_notifying || ni == NULL)
 139                 return;
 140
 141         lp->lp_notifying = 1;
 142
 143         while (lp->lp_notify) {
 144                 alive = lp->lp_alive;
 145                 notifylnd = lp->lp_notifylnd;
 146
 147                 lp->lp_notifylnd = 0;
 148                 lp->lp_notify    = 0;
 149
 150                 if (notifylnd && ni->ni_lnd->lnd_notify != NULL) {
 151                         lnet_net_unlock(lp->lp_cpt);
 152
 153                         /* A new notification could happen now; I'll handle it
 154                          * when control returns to me */
 155
 156                         (ni->ni_lnd->lnd_notify)(ni, lp->lp_nid, alive);
 157
 158                         lnet_net_lock(lp->lp_cpt);
 159                 }
 160         }
 161
 162         lp->lp_notifying = 0;
 163 }
 164
 165 static void
 166 lnet_rtr_addref_locked(lnet_peer_t *lp)
 167 {
 168         LASSERT(lp->lp_refcount > 0);
 169         LASSERT(lp->lp_rtr_refcount >= 0);
 170
 171         /* lnet_net_lock must be exclusively locked */
 172         lp->lp_rtr_refcount++;
 173         if (lp->lp_rtr_refcount == 1) {
 174                 struct list_head *pos;
 175
 176                 /* a simple insertion sort */
 177                 list_for_each_prev(pos, &the_lnet.ln_routers) {
 178                         lnet_peer_t *rtr = list_entry(pos, lnet_peer_t,
 179                                                           lp_rtr_list);
 180
 181                         if (rtr->lp_nid < lp->lp_nid)
 182                                 break;
 183                 }
 184
 185                 list_add(&lp->lp_rtr_list, pos);
 186                 /* addref for the_lnet.ln_routers */
 187                 lnet_peer_addref_locked(lp);
 188                 the_lnet.ln_routers_version++;
 189         }
 190 }
 191
 192 static void
 193 lnet_rtr_decref_locked(lnet_peer_t *lp)
 194 {
 195         LASSERT(lp->lp_refcount > 0);
 196         LASSERT(lp->lp_rtr_refcount > 0);
 197
 198         /* lnet_net_lock must be exclusively locked */
 199         lp->lp_rtr_refcount--;
 200         if (lp->lp_rtr_refcount == 0) {
 201                 LASSERT(list_empty(&lp->lp_routes));
 202
 203                 if (lp->lp_rcd != NULL) {
 204                         list_add(&lp->lp_rcd->rcd_list,
 205                                      &the_lnet.ln_rcd_deathrow);
 206                         lp->lp_rcd = NULL;
 207                 }
 208
 209                 list_del(&lp->lp_rtr_list);
 210                 /* decref for the_lnet.ln_routers */
 211                 lnet_peer_decref_locked(lp);
 212                 the_lnet.ln_routers_version++;
 213         }
 214 }
 215
 216 lnet_remotenet_t *
 217 lnet_find_net_locked(__u32 net)
 218 {
 219         lnet_remotenet_t *rnet;
 220         struct list_head *tmp;
 221         struct list_head *rn_list;
 222
 223         LASSERT(!the_lnet.ln_shutdown);
 224
 225         rn_list = lnet_net2rnethash(net);
 226         list_for_each(tmp, rn_list) {
 227                 rnet = list_entry(tmp, lnet_remotenet_t, lrn_list);
 228
 229                 if (rnet->lrn_net == net)
 230                         return rnet;
 231         }
 232         return NULL;
 233 }
 234
 235 static void lnet_shuffle_seed(void)
 236 {
 237         static int seeded;
 238         __u32 lnd_type, seed[2];
 239         struct timespec64 ts;
 240         lnet_ni_t *ni;
 241         struct list_head *tmp;
 242
 243         if (seeded)
 244                 return;
 245
 246         cfs_get_random_bytes(seed, sizeof(seed));
 247
 248         /* Nodes with small feet have little entropy
 249          * the NID for this node gives the most entropy in the low bits */
 250         list_for_each(tmp, &the_lnet.ln_nis) {
 251                 ni = list_entry(tmp, lnet_ni_t, ni_list);
 252                 lnd_type = LNET_NETTYP(LNET_NIDNET(ni->ni_nid));
 253
 254                 if (lnd_type != LOLND)
 255                         seed[0] ^= (LNET_NIDADDR(ni->ni_nid) | lnd_type);
 256         }
 257
 258         ktime_get_ts64(&ts);
 259         cfs_srand(ts.tv_sec ^ seed[0], ts.tv_nsec ^ seed[1]);
 260         seeded = 1;
 261 }
 262
 263 /* NB expects LNET_LOCK held */
 264 static void
 265 lnet_add_route_to_rnet(lnet_remotenet_t *rnet, lnet_route_t *route)
 266 {
 267         unsigned int len = 0;
 268         unsigned int offset = 0;
 269         struct list_head *e;
 270
 271         lnet_shuffle_seed();
 272
 273         list_for_each(e, &rnet->lrn_routes) {
 274                 len++;
 275         }
 276
 277         /* len+1 positions to add a new entry, also prevents division by 0 */
 278         offset = cfs_rand() % (len + 1);
 279         list_for_each(e, &rnet->lrn_routes) {
 280                 if (offset == 0)
 281                         break;
 282                 offset--;
 283         }
 284         list_add(&route->lr_list, e);
 285         list_add(&route->lr_gwlist, &route->lr_gateway->lp_routes);
 286
 287         the_lnet.ln_remote_nets_version++;
 288         lnet_rtr_addref_locked(route->lr_gateway);
 289 }
 290
 291 int
 292 lnet_add_route(__u32 net, unsigned int hops, lnet_nid_t gateway,
 293                unsigned int priority)
 294 {
 295         struct list_head *e;
 296         lnet_remotenet_t *rnet;
 297         lnet_remotenet_t *rnet2;
 298         lnet_route_t *route;
 299         lnet_ni_t *ni;
 300         int add_route;
 301         int rc;
 302
 303         CDEBUG(D_NET, "Add route: net %s hops %u priority %u gw %s\n",
 304                libcfs_net2str(net), hops, priority, libcfs_nid2str(gateway));
 305
 306         if (gateway == LNET_NID_ANY ||
 307             LNET_NETTYP(LNET_NIDNET(gateway)) == LOLND ||
 308             net == LNET_NIDNET(LNET_NID_ANY) ||
 309             LNET_NETTYP(net) == LOLND ||
 310             LNET_NIDNET(gateway) == net ||
 311             hops < 1 || hops > 255)
 312                 return -EINVAL;
 313
 314         if (lnet_islocalnet(net))              /* it's a local network */
 315                 return 0;                      /* ignore the route entry */
 316
 317         /* Assume net, route, all new */
 318         LIBCFS_ALLOC(route, sizeof(*route));
 319         LIBCFS_ALLOC(rnet, sizeof(*rnet));
 320         if (route == NULL || rnet == NULL) {
 321                 CERROR("Out of memory creating route %s %d %s\n",
 322                        libcfs_net2str(net), hops, libcfs_nid2str(gateway));
 323                 if (route != NULL)
 324                         LIBCFS_FREE(route, sizeof(*route));
 325                 if (rnet != NULL)
 326                         LIBCFS_FREE(rnet, sizeof(*rnet));
 327                 return -ENOMEM;
 328         }
 329
 330         INIT_LIST_HEAD(&rnet->lrn_routes);
 331         rnet->lrn_net = net;
 332         route->lr_hops = hops;
 333         route->lr_net = net;
 334         route->lr_priority = priority;
 335
 336         lnet_net_lock(LNET_LOCK_EX);
 337
 338         rc = lnet_nid2peer_locked(&route->lr_gateway, gateway, LNET_LOCK_EX);
 339         if (rc != 0) {
 340                 lnet_net_unlock(LNET_LOCK_EX);
 341
 342                 LIBCFS_FREE(route, sizeof(*route));
 343                 LIBCFS_FREE(rnet, sizeof(*rnet));
 344
 345                 if (rc == -EHOSTUNREACH) /* gateway is not on a local net */
 346                         return 0;       /* ignore the route entry */
 347                 CERROR("Error %d creating route %s %d %s\n", rc,
 348                        libcfs_net2str(net), hops,
 349                        libcfs_nid2str(gateway));
 350
 351                 return rc;
 352         }
 353
 354         LASSERT(!the_lnet.ln_shutdown);
 355
 356         rnet2 = lnet_find_net_locked(net);
 357         if (rnet2 == NULL) {
 358                 /* new network */
 359                 list_add_tail(&rnet->lrn_list, lnet_net2rnethash(net));
 360                 rnet2 = rnet;
 361         }
 362
 363         /* Search for a duplicate route (it's a NOOP if it is) */
 364         add_route = 1;
 365         list_for_each(e, &rnet2->lrn_routes) {
 366                 lnet_route_t *route2 = list_entry(e, lnet_route_t, lr_list);
 367
 368                 if (route2->lr_gateway == route->lr_gateway) {
 369                         add_route = 0;
 370                         break;
 371                 }
 372
 373                 /* our lookups must be true */
 374                 LASSERT(route2->lr_gateway->lp_nid != gateway);
 375         }
 376
 377         if (add_route) {
 378                 lnet_peer_addref_locked(route->lr_gateway); /* +1 for notify */
 379                 lnet_add_route_to_rnet(rnet2, route);
 380
 381                 ni = route->lr_gateway->lp_ni;
 382                 lnet_net_unlock(LNET_LOCK_EX);
 383
 384                 /* XXX Assume alive */
 385                 if (ni->ni_lnd->lnd_notify != NULL)
 386                         (ni->ni_lnd->lnd_notify)(ni, gateway, 1);
 387
 388                 lnet_net_lock(LNET_LOCK_EX);
 389         }
 390
 391         /* -1 for notify or !add_route */
 392         lnet_peer_decref_locked(route->lr_gateway);
 393         lnet_net_unlock(LNET_LOCK_EX);
 394
 395         if (!add_route)
 396                 LIBCFS_FREE(route, sizeof(*route));
 397
 398         if (rnet != rnet2)
 399                 LIBCFS_FREE(rnet, sizeof(*rnet));
 400
 401         return 0;
 402 }
 403
 404 int
 405 lnet_check_routes(void)
 406 {
 407         lnet_remotenet_t *rnet;
 408         lnet_route_t *route;
 409         lnet_route_t *route2;
 410         struct list_head *e1;
 411         struct list_head *e2;
 412         int cpt;
 413         struct list_head *rn_list;
 414         int i;
 415
 416         cpt = lnet_net_lock_current();
 417
 418         for (i = 0; i < LNET_REMOTE_NETS_HASH_SIZE; i++) {
 419                 rn_list = &the_lnet.ln_remote_nets_hash[i];
 420                 list_for_each(e1, rn_list) {
 421                         rnet = list_entry(e1, lnet_remotenet_t, lrn_list);
 422
 423                         route2 = NULL;
 424                         list_for_each(e2, &rnet->lrn_routes) {
 425                                 lnet_nid_t nid1;
 426                                 lnet_nid_t nid2;
 427                                 int net;
 428
 429                                 route = list_entry(e2, lnet_route_t,
 430                                                        lr_list);
 431
 432                                 if (route2 == NULL) {
 433                                         route2 = route;
 434                                         continue;
 435                                 }
 436
 437                                 if (route->lr_gateway->lp_ni ==
 438                                     route2->lr_gateway->lp_ni)
 439                                         continue;
 440
 441                                 nid1 = route->lr_gateway->lp_nid;
 442                                 nid2 = route2->lr_gateway->lp_nid;
 443                                 net = rnet->lrn_net;
 444
 445                                 lnet_net_unlock(cpt);
 446
 447                                 CERROR("Routes to %s via %s and %s not supported\n",
 448                                        libcfs_net2str(net),
 449                                        libcfs_nid2str(nid1),
 450                                        libcfs_nid2str(nid2));
 451                                 return -EINVAL;
 452                         }
 453                 }
 454         }
 455
 456         lnet_net_unlock(cpt);
 457         return 0;
 458 }
 459
 460 int
 461 lnet_del_route(__u32 net, lnet_nid_t gw_nid)
 462 {
 463         struct lnet_peer *gateway;
 464         lnet_remotenet_t *rnet;
 465         lnet_route_t *route;
 466         struct list_head *e1;
 467         struct list_head *e2;
 468         int rc = -ENOENT;
 469         struct list_head *rn_list;
 470         int idx = 0;
 471
 472         CDEBUG(D_NET, "Del route: net %s : gw %s\n",
 473                libcfs_net2str(net), libcfs_nid2str(gw_nid));
 474
 475         /* NB Caller may specify either all routes via the given gateway
 476          * or a specific route entry actual NIDs) */
 477
 478         lnet_net_lock(LNET_LOCK_EX);
 479         if (net == LNET_NIDNET(LNET_NID_ANY))
 480                 rn_list = &the_lnet.ln_remote_nets_hash[0];
 481         else
 482                 rn_list = lnet_net2rnethash(net);
 483
 484  again:
 485         list_for_each(e1, rn_list) {
 486                 rnet = list_entry(e1, lnet_remotenet_t, lrn_list);
 487
 488                 if (!(net == LNET_NIDNET(LNET_NID_ANY) ||
 489                         net == rnet->lrn_net))
 490                         continue;
 491
 492                 list_for_each(e2, &rnet->lrn_routes) {
 493                         route = list_entry(e2, lnet_route_t, lr_list);
 494
 495                         gateway = route->lr_gateway;
 496                         if (!(gw_nid == LNET_NID_ANY ||
 497                               gw_nid == gateway->lp_nid))
 498                                 continue;
 499
 500                         list_del(&route->lr_list);
 501                         list_del(&route->lr_gwlist);
 502                         the_lnet.ln_remote_nets_version++;
 503
 504                         if (list_empty(&rnet->lrn_routes))
 505                                 list_del(&rnet->lrn_list);
 506                         else
 507                                 rnet = NULL;
 508
 509                         lnet_rtr_decref_locked(gateway);
 510                         lnet_peer_decref_locked(gateway);
 511
 512                         lnet_net_unlock(LNET_LOCK_EX);
 513
 514                         LIBCFS_FREE(route, sizeof(*route));
 515
 516                         if (rnet != NULL)
 517                                 LIBCFS_FREE(rnet, sizeof(*rnet));
 518
 519                         rc = 0;
 520                         lnet_net_lock(LNET_LOCK_EX);
 521                         goto again;
 522                 }
 523         }
 524
 525         if (net == LNET_NIDNET(LNET_NID_ANY) &&
 526             ++idx < LNET_REMOTE_NETS_HASH_SIZE) {
 527                 rn_list = &the_lnet.ln_remote_nets_hash[idx];
 528                 goto again;
 529         }
 530         lnet_net_unlock(LNET_LOCK_EX);
 531
 532         return rc;
 533 }
 534
 535 void
 536 lnet_destroy_routes(void)
 537 {
 538         lnet_del_route(LNET_NIDNET(LNET_NID_ANY), LNET_NID_ANY);
 539 }
 540
 541 int
 542 lnet_get_route(int idx, __u32 *net, __u32 *hops,
 543                lnet_nid_t *gateway, __u32 *alive, __u32 *priority)
 544 {
 545         struct list_head *e1;
 546         struct list_head *e2;
 547         lnet_remotenet_t *rnet;
 548         lnet_route_t *route;
 549         int cpt;
 550         int i;
 551         struct list_head *rn_list;
 552
 553         cpt = lnet_net_lock_current();
 554
 555         for (i = 0; i < LNET_REMOTE_NETS_HASH_SIZE; i++) {
 556                 rn_list = &the_lnet.ln_remote_nets_hash[i];
 557                 list_for_each(e1, rn_list) {
 558                         rnet = list_entry(e1, lnet_remotenet_t, lrn_list);
 559
 560                         list_for_each(e2, &rnet->lrn_routes) {
 561                                 route = list_entry(e2, lnet_route_t,
 562                                                        lr_list);
 563
 564                                 if (idx-- == 0) {
 565                                         *net      = rnet->lrn_net;
 566                                         *hops     = route->lr_hops;
 567                                         *priority = route->lr_priority;
 568                                         *gateway  = route->lr_gateway->lp_nid;
 569                                         *alive    = route->lr_gateway->lp_alive;
 570                                         lnet_net_unlock(cpt);
 571                                         return 0;
 572                                 }
 573                         }
 574                 }
 575         }
 576
 577         lnet_net_unlock(cpt);
 578         return -ENOENT;
 579 }
 580
 581 void
 582 lnet_swap_pinginfo(lnet_ping_info_t *info)
 583 {
 584         int i;
 585         lnet_ni_status_t *stat;
 586
 587         __swab32s(&info->pi_magic);
 588         __swab32s(&info->pi_features);
 589         __swab32s(&info->pi_pid);
 590         __swab32s(&info->pi_nnis);
 591         for (i = 0; i < info->pi_nnis && i < LNET_MAX_RTR_NIS; i++) {
 592                 stat = &info->pi_ni[i];
 593                 __swab64s(&stat->ns_nid);
 594                 __swab32s(&stat->ns_status);
 595         }
 596 }
 597
 598 /**
 599  * parse router-checker pinginfo, record number of down NIs for remote
 600  * networks on that router.
 601  */
 602 static void
 603 lnet_parse_rc_info(lnet_rc_data_t *rcd)
 604 {
 605         lnet_ping_info_t *info = rcd->rcd_pinginfo;
 606         struct lnet_peer *gw = rcd->rcd_gateway;
 607         lnet_route_t *rtr;
 608
 609         if (!gw->lp_alive)
 610                 return;
 611
 612         if (info->pi_magic == __swab32(LNET_PROTO_PING_MAGIC))
 613                 lnet_swap_pinginfo(info);
 614
 615         /* NB always racing with network! */
 616         if (info->pi_magic != LNET_PROTO_PING_MAGIC) {
 617                 CDEBUG(D_NET, "%s: Unexpected magic %08x\n",
 618                        libcfs_nid2str(gw->lp_nid), info->pi_magic);
 619                 gw->lp_ping_feats = LNET_PING_FEAT_INVAL;
 620                 return;
 621         }
 622
 623         gw->lp_ping_feats = info->pi_features;
 624         if ((gw->lp_ping_feats & LNET_PING_FEAT_MASK) == 0) {
 625                 CDEBUG(D_NET, "%s: Unexpected features 0x%x\n",
 626                        libcfs_nid2str(gw->lp_nid), gw->lp_ping_feats);
 627                 return; /* nothing I can understand */
 628         }
 629
 630         if ((gw->lp_ping_feats & LNET_PING_FEAT_NI_STATUS) == 0)
 631                 return; /* can't carry NI status info */
 632
 633         list_for_each_entry(rtr, &gw->lp_routes, lr_gwlist) {
 634                 int ptl_status = LNET_NI_STATUS_INVALID;
 635                 int down = 0;
 636                 int up = 0;
 637                 int i;
 638
 639                 for (i = 0; i < info->pi_nnis && i < LNET_MAX_RTR_NIS; i++) {
 640                         lnet_ni_status_t *stat = &info->pi_ni[i];
 641                         lnet_nid_t nid = stat->ns_nid;
 642
 643                         if (nid == LNET_NID_ANY) {
 644                                 CDEBUG(D_NET, "%s: unexpected LNET_NID_ANY\n",
 645                                        libcfs_nid2str(gw->lp_nid));
 646                                 gw->lp_ping_feats = LNET_PING_FEAT_INVAL;
 647                                 return;
 648                         }
 649
 650                         if (LNET_NETTYP(LNET_NIDNET(nid)) == LOLND)
 651                                 continue;
 652
 653                         if (stat->ns_status == LNET_NI_STATUS_DOWN) {
 654                                 if (LNET_NETTYP(LNET_NIDNET(nid)) != PTLLND)
 655                                         down++;
 656                                 else if (ptl_status != LNET_NI_STATUS_UP)
 657                                         ptl_status = LNET_NI_STATUS_DOWN;
 658                                 continue;
 659                         }
 660
 661                         if (stat->ns_status == LNET_NI_STATUS_UP) {
 662                                 if (LNET_NIDNET(nid) == rtr->lr_net) {
 663                                         up = 1;
 664                                         break;
 665                                 }
 666                                 /* ptl NIs are considered down only when
 667                                  * they're all down */
 668                                 if (LNET_NETTYP(LNET_NIDNET(nid)) == PTLLND)
 669                                         ptl_status = LNET_NI_STATUS_UP;
 670                                 continue;
 671                         }
 672
 673                         CDEBUG(D_NET, "%s: Unexpected status 0x%x\n",
 674                                libcfs_nid2str(gw->lp_nid), stat->ns_status);
 675                         gw->lp_ping_feats = LNET_PING_FEAT_INVAL;
 676                         return;
 677                 }
 678
 679                 if (up) { /* ignore downed NIs if NI for dest network is up */
 680                         rtr->lr_downis = 0;
 681                         continue;
 682                 }
 683                 rtr->lr_downis = down + (ptl_status == LNET_NI_STATUS_DOWN);
 684         }
 685 }
 686
 687 static void
 688 lnet_router_checker_event(lnet_event_t *event)
 689 {
 690         lnet_rc_data_t *rcd = event->md.user_ptr;
 691         struct lnet_peer *lp;
 692
 693         LASSERT(rcd != NULL);
 694
 695         if (event->unlinked) {
 696                 LNetInvalidateHandle(&rcd->rcd_mdh);
 697                 return;
 698         }
 699
 700         LASSERT(event->type == LNET_EVENT_SEND ||
 701                 event->type == LNET_EVENT_REPLY);
 702
 703         lp = rcd->rcd_gateway;
 704         LASSERT(lp != NULL);
 705
 706          /* NB: it's called with holding lnet_res_lock, we have a few
 707           * places need to hold both locks at the same time, please take
 708           * care of lock ordering */
 709         lnet_net_lock(lp->lp_cpt);
 710         if (!lnet_isrouter(lp) || lp->lp_rcd != rcd) {
 711                 /* ignore if no longer a router or rcd is replaced */
 712                 goto out;
 713         }
 714
 715         if (event->type == LNET_EVENT_SEND) {
 716                 lp->lp_ping_notsent = 0;
 717                 if (event->status == 0)
 718                         goto out;
 719         }
 720
 721         /* LNET_EVENT_REPLY */
 722         /* A successful REPLY means the router is up.  If _any_ comms
 723          * to the router fail I assume it's down (this will happen if
 724          * we ping alive routers to try to detect router death before
 725          * apps get burned). */
 726
 727         lnet_notify_locked(lp, 1, (event->status == 0), cfs_time_current());
 728         /* The router checker will wake up very shortly and do the
 729          * actual notification.
 730          * XXX If 'lp' stops being a router before then, it will still
 731          * have the notification pending!!! */
 732
 733         if (avoid_asym_router_failure && event->status == 0)
 734                 lnet_parse_rc_info(rcd);
 735
 736  out:
 737         lnet_net_unlock(lp->lp_cpt);
 738 }
 739
 740 static void
 741 lnet_wait_known_routerstate(void)
 742 {
 743         lnet_peer_t *rtr;
 744         struct list_head *entry;
 745         int all_known;
 746
 747         LASSERT(the_lnet.ln_rc_state == LNET_RC_STATE_RUNNING);
 748
 749         for (;;) {
 750                 int cpt = lnet_net_lock_current();
 751
 752                 all_known = 1;
 753                 list_for_each(entry, &the_lnet.ln_routers) {
 754                         rtr = list_entry(entry, lnet_peer_t, lp_rtr_list);
 755
 756                         if (rtr->lp_alive_count == 0) {
 757                                 all_known = 0;
 758                                 break;
 759                         }
 760                 }
 761
 762                 lnet_net_unlock(cpt);
 763
 764                 if (all_known)
 765                         return;
 766
 767                 set_current_state(TASK_UNINTERRUPTIBLE);
 768                 schedule_timeout(cfs_time_seconds(1));
 769         }
 770 }
 771
 772 void
 773 lnet_router_ni_update_locked(lnet_peer_t *gw, __u32 net)
 774 {
 775         lnet_route_t *rte;
 776
 777         if ((gw->lp_ping_feats & LNET_PING_FEAT_NI_STATUS) != 0) {
 778                 list_for_each_entry(rte, &gw->lp_routes, lr_gwlist) {
 779                         if (rte->lr_net == net) {
 780                                 rte->lr_downis = 0;
 781                                 break;
 782                         }
 783                 }
 784         }
 785 }
 786
 787 static void
 788 lnet_update_ni_status_locked(void)
 789 {
 790         lnet_ni_t *ni;
 791         time64_t now;
 792         int timeout;
 793
 794         LASSERT(the_lnet.ln_routing);
 795
 796         timeout = router_ping_timeout +
 797                   max(live_router_check_interval, dead_router_check_interval);
 798
 799         now = ktime_get_real_seconds();
 800         list_for_each_entry(ni, &the_lnet.ln_nis, ni_list) {
 801                 if (ni->ni_lnd->lnd_type == LOLND)
 802                         continue;
 803
 804                 if (now < ni->ni_last_alive + timeout)
 805                         continue;
 806
 807                 lnet_ni_lock(ni);
 808                 /* re-check with lock */
 809                 if (now < ni->ni_last_alive + timeout) {
 810                         lnet_ni_unlock(ni);
 811                         continue;
 812                 }
 813
 814                 LASSERT(ni->ni_status != NULL);
 815
 816                 if (ni->ni_status->ns_status != LNET_NI_STATUS_DOWN) {
 817                         CDEBUG(D_NET, "NI(%s:%d) status changed to down\n",
 818                                libcfs_nid2str(ni->ni_nid), timeout);
 819                         /* NB: so far, this is the only place to set
 820                          * NI status to "down" */
 821                         ni->ni_status->ns_status = LNET_NI_STATUS_DOWN;
 822                 }
 823                 lnet_ni_unlock(ni);
 824         }
 825 }
 826
 827 static void
 828 lnet_destroy_rc_data(lnet_rc_data_t *rcd)
 829 {
 830         LASSERT(list_empty(&rcd->rcd_list));
 831         /* detached from network */
 832         LASSERT(LNetHandleIsInvalid(rcd->rcd_mdh));
 833
 834         if (rcd->rcd_gateway != NULL) {
 835                 int cpt = rcd->rcd_gateway->lp_cpt;
 836
 837                 lnet_net_lock(cpt);
 838                 lnet_peer_decref_locked(rcd->rcd_gateway);
 839                 lnet_net_unlock(cpt);
 840         }
 841
 842         if (rcd->rcd_pinginfo != NULL)
 843                 LIBCFS_FREE(rcd->rcd_pinginfo, LNET_PINGINFO_SIZE);
 844
 845         LIBCFS_FREE(rcd, sizeof(*rcd));
 846 }
 847
 848 static lnet_rc_data_t *
 849 lnet_create_rc_data_locked(lnet_peer_t *gateway)
 850 {
 851         lnet_rc_data_t *rcd = NULL;
 852         lnet_ping_info_t *pi;
 853         int rc;
 854         int i;
 855
 856         lnet_net_unlock(gateway->lp_cpt);
 857
 858         LIBCFS_ALLOC(rcd, sizeof(*rcd));
 859         if (rcd == NULL)
 860                 goto out;
 861
 862         LNetInvalidateHandle(&rcd->rcd_mdh);
 863         INIT_LIST_HEAD(&rcd->rcd_list);
 864
 865         LIBCFS_ALLOC(pi, LNET_PINGINFO_SIZE);
 866         if (pi == NULL)
 867                 goto out;
 868
 869         for (i = 0; i < LNET_MAX_RTR_NIS; i++) {
 870                 pi->pi_ni[i].ns_nid = LNET_NID_ANY;
 871                 pi->pi_ni[i].ns_status = LNET_NI_STATUS_INVALID;
 872         }
 873         rcd->rcd_pinginfo = pi;
 874
 875         LASSERT(!LNetHandleIsInvalid(the_lnet.ln_rc_eqh));
 876         rc = LNetMDBind((lnet_md_t){.start     = pi,
 877                                     .user_ptr  = rcd,
 878                                     .length    = LNET_PINGINFO_SIZE,
 879                                     .threshold = LNET_MD_THRESH_INF,
 880                                     .options   = LNET_MD_TRUNCATE,
 881                                     .eq_handle = the_lnet.ln_rc_eqh},
 882                         LNET_UNLINK,
 883                         &rcd->rcd_mdh);
 884         if (rc < 0) {
 885                 CERROR("Can't bind MD: %d\n", rc);
 886                 goto out;
 887         }
 888         LASSERT(rc == 0);
 889
 890         lnet_net_lock(gateway->lp_cpt);
 891         /* router table changed or someone has created rcd for this gateway */
 892         if (!lnet_isrouter(gateway) || gateway->lp_rcd != NULL) {
 893                 lnet_net_unlock(gateway->lp_cpt);
 894                 goto out;
 895         }
 896
 897         lnet_peer_addref_locked(gateway);
 898         rcd->rcd_gateway = gateway;
 899         gateway->lp_rcd = rcd;
 900         gateway->lp_ping_notsent = 0;
 901
 902         return rcd;
 903
 904  out:
 905         if (rcd != NULL) {
 906                 if (!LNetHandleIsInvalid(rcd->rcd_mdh)) {
 907                         rc = LNetMDUnlink(rcd->rcd_mdh);
 908                         LASSERT(rc == 0);
 909                 }
 910                 lnet_destroy_rc_data(rcd);
 911         }
 912
 913         lnet_net_lock(gateway->lp_cpt);
 914         return gateway->lp_rcd;
 915 }
 916
 917 static int
 918 lnet_router_check_interval(lnet_peer_t *rtr)
 919 {
 920         int secs;
 921
 922         secs = rtr->lp_alive ? live_router_check_interval :
 923                                dead_router_check_interval;
 924         if (secs < 0)
 925                 secs = 0;
 926
 927         return secs;
 928 }
 929
 930 static void
 931 lnet_ping_router_locked(lnet_peer_t *rtr)
 932 {
 933         lnet_rc_data_t *rcd = NULL;
 934         unsigned long now = cfs_time_current();
 935         int secs;
 936
 937         lnet_peer_addref_locked(rtr);
 938
 939         if (rtr->lp_ping_deadline != 0 && /* ping timed out? */
 940             cfs_time_after(now, rtr->lp_ping_deadline))
 941                 lnet_notify_locked(rtr, 1, 0, now);
 942
 943         /* Run any outstanding notifications */
 944         lnet_ni_notify_locked(rtr->lp_ni, rtr);
 945
 946         if (!lnet_isrouter(rtr) ||
 947             the_lnet.ln_rc_state != LNET_RC_STATE_RUNNING) {
 948                 /* router table changed or router checker is shutting down */
 949                 lnet_peer_decref_locked(rtr);
 950                 return;
 951         }
 952
 953         rcd = rtr->lp_rcd != NULL ?
 954               rtr->lp_rcd : lnet_create_rc_data_locked(rtr);
 955
 956         if (rcd == NULL)
 957                 return;
 958
 959         secs = lnet_router_check_interval(rtr);
 960
 961         CDEBUG(D_NET,
 962                "rtr %s %d: deadline %lu ping_notsent %d alive %d alive_count %d lp_ping_timestamp %lu\n",
 963                libcfs_nid2str(rtr->lp_nid), secs,
 964                rtr->lp_ping_deadline, rtr->lp_ping_notsent,
 965                rtr->lp_alive, rtr->lp_alive_count, rtr->lp_ping_timestamp);
 966
 967         if (secs != 0 && !rtr->lp_ping_notsent &&
 968             cfs_time_after(now, cfs_time_add(rtr->lp_ping_timestamp,
 969                                              cfs_time_seconds(secs)))) {
 970                 int rc;
 971                 lnet_process_id_t id;
 972                 lnet_handle_md_t mdh;
 973
 974                 id.nid = rtr->lp_nid;
 975                 id.pid = LUSTRE_SRV_LNET_PID;
 976                 CDEBUG(D_NET, "Check: %s\n", libcfs_id2str(id));
 977
 978                 rtr->lp_ping_notsent   = 1;
 979                 rtr->lp_ping_timestamp = now;
 980
 981                 mdh = rcd->rcd_mdh;
 982
 983                 if (rtr->lp_ping_deadline == 0) {
 984                         rtr->lp_ping_deadline =
 985                                 cfs_time_shift(router_ping_timeout);
 986                 }
 987
 988                 lnet_net_unlock(rtr->lp_cpt);
 989
 990                 rc = LNetGet(LNET_NID_ANY, mdh, id, LNET_RESERVED_PORTAL,
 991                              LNET_PROTO_PING_MATCHBITS, 0);
 992
 993                 lnet_net_lock(rtr->lp_cpt);
 994                 if (rc != 0)
 995                         rtr->lp_ping_notsent = 0; /* no event pending */
 996         }
 997
 998         lnet_peer_decref_locked(rtr);
 999 }
1000
1001 int
1002 lnet_router_checker_start(void)
1003 {
1004         int rc;
1005         int eqsz;
1006
1007         LASSERT(the_lnet.ln_rc_state == LNET_RC_STATE_SHUTDOWN);
1008
1009         if (check_routers_before_use &&
1010             dead_router_check_interval <= 0) {
1011                 LCONSOLE_ERROR_MSG(0x10a, "'dead_router_check_interval' must be set if 'check_routers_before_use' is set\n");
1012                 return -EINVAL;
1013         }
1014
1015         if (!the_lnet.ln_routing &&
1016             live_router_check_interval <= 0 &&
1017             dead_router_check_interval <= 0)
1018                 return 0;
1019
1020         sema_init(&the_lnet.ln_rc_signal, 0);
1021         /* EQ size doesn't matter; the callback is guaranteed to get every
1022          * event */
1023         eqsz = 0;
1024         rc = LNetEQAlloc(eqsz, lnet_router_checker_event,
1025                          &the_lnet.ln_rc_eqh);
1026         if (rc != 0) {
1027                 CERROR("Can't allocate EQ(%d): %d\n", eqsz, rc);
1028                 return -ENOMEM;
1029         }
1030
1031         the_lnet.ln_rc_state = LNET_RC_STATE_RUNNING;
1032         rc = PTR_ERR(kthread_run(lnet_router_checker,
1033                                  NULL, "router_checker"));
1034         if (IS_ERR_VALUE(rc)) {
1035                 CERROR("Can't start router checker thread: %d\n", rc);
1036                 /* block until event callback signals exit */
1037                 down(&the_lnet.ln_rc_signal);
1038                 rc = LNetEQFree(the_lnet.ln_rc_eqh);
1039                 LASSERT(rc == 0);
1040                 the_lnet.ln_rc_state = LNET_RC_STATE_SHUTDOWN;
1041                 return -ENOMEM;
1042         }
1043
1044         if (check_routers_before_use) {
1045                 /* Note that a helpful side-effect of pinging all known routers
1046                  * at startup is that it makes them drop stale connections they
1047                  * may have to a previous instance of me. */
1048                 lnet_wait_known_routerstate();
1049         }
1050
1051         return 0;
1052 }
1053
1054 void
1055 lnet_router_checker_stop(void)
1056 {
1057         int rc;
1058
1059         if (the_lnet.ln_rc_state == LNET_RC_STATE_SHUTDOWN)
1060                 return;
1061
1062         LASSERT(the_lnet.ln_rc_state == LNET_RC_STATE_RUNNING);
1063         the_lnet.ln_rc_state = LNET_RC_STATE_STOPPING;
1064
1065         /* block until event callback signals exit */
1066         down(&the_lnet.ln_rc_signal);
1067         LASSERT(the_lnet.ln_rc_state == LNET_RC_STATE_SHUTDOWN);
1068
1069         rc = LNetEQFree(the_lnet.ln_rc_eqh);
1070         LASSERT(rc == 0);
1071 }
1072
1073 static void
1074 lnet_prune_rc_data(int wait_unlink)
1075 {
1076         lnet_rc_data_t *rcd;
1077         lnet_rc_data_t *tmp;
1078         lnet_peer_t *lp;
1079         struct list_head head;
1080         int i = 2;
1081
1082         if (likely(the_lnet.ln_rc_state == LNET_RC_STATE_RUNNING &&
1083                    list_empty(&the_lnet.ln_rcd_deathrow) &&
1084                    list_empty(&the_lnet.ln_rcd_zombie)))
1085                 return;
1086
1087         INIT_LIST_HEAD(&head);
1088
1089         lnet_net_lock(LNET_LOCK_EX);
1090
1091         if (the_lnet.ln_rc_state != LNET_RC_STATE_RUNNING) {
1092                 /* router checker is stopping, prune all */
1093                 list_for_each_entry(lp, &the_lnet.ln_routers,
1094                                         lp_rtr_list) {
1095                         if (lp->lp_rcd == NULL)
1096                                 continue;
1097
1098                         LASSERT(list_empty(&lp->lp_rcd->rcd_list));
1099                         list_add(&lp->lp_rcd->rcd_list,
1100                                      &the_lnet.ln_rcd_deathrow);
1101                         lp->lp_rcd = NULL;
1102                 }
1103         }
1104
1105         /* unlink all RCDs on deathrow list */
1106         list_splice_init(&the_lnet.ln_rcd_deathrow, &head);
1107
1108         if (!list_empty(&head)) {
1109                 lnet_net_unlock(LNET_LOCK_EX);
1110
1111                 list_for_each_entry(rcd, &head, rcd_list)
1112                         LNetMDUnlink(rcd->rcd_mdh);
1113
1114                 lnet_net_lock(LNET_LOCK_EX);
1115         }
1116
1117         list_splice_init(&head, &the_lnet.ln_rcd_zombie);
1118
1119         /* release all zombie RCDs */
1120         while (!list_empty(&the_lnet.ln_rcd_zombie)) {
1121                 list_for_each_entry_safe(rcd, tmp, &the_lnet.ln_rcd_zombie,
1122                                              rcd_list) {
1123                         if (LNetHandleIsInvalid(rcd->rcd_mdh))
1124                                 list_move(&rcd->rcd_list, &head);
1125                 }
1126
1127                 wait_unlink = wait_unlink &&
1128                               !list_empty(&the_lnet.ln_rcd_zombie);
1129
1130                 lnet_net_unlock(LNET_LOCK_EX);
1131
1132                 while (!list_empty(&head)) {
1133                         rcd = list_entry(head.next,
1134                                              lnet_rc_data_t, rcd_list);
1135                         list_del_init(&rcd->rcd_list);
1136                         lnet_destroy_rc_data(rcd);
1137                 }
1138
1139                 if (!wait_unlink)
1140                         return;
1141
1142                 i++;
1143                 CDEBUG(((i & (-i)) == i) ? D_WARNING : D_NET,
1144                        "Waiting for rc buffers to unlink\n");
1145                 set_current_state(TASK_UNINTERRUPTIBLE);
1146                 schedule_timeout(cfs_time_seconds(1) / 4);
1147
1148                 lnet_net_lock(LNET_LOCK_EX);
1149         }
1150
1151         lnet_net_unlock(LNET_LOCK_EX);
1152 }
1153
1154 static int
1155 lnet_router_checker(void *arg)
1156 {
1157         lnet_peer_t *rtr;
1158         struct list_head *entry;
1159
1160         cfs_block_allsigs();
1161
1162         LASSERT(the_lnet.ln_rc_state == LNET_RC_STATE_RUNNING);
1163
1164         while (the_lnet.ln_rc_state == LNET_RC_STATE_RUNNING) {
1165                 __u64 version;
1166                 int cpt;
1167                 int cpt2;
1168
1169                 cpt = lnet_net_lock_current();
1170 rescan:
1171                 version = the_lnet.ln_routers_version;
1172
1173                 list_for_each(entry, &the_lnet.ln_routers) {
1174                         rtr = list_entry(entry, lnet_peer_t, lp_rtr_list);
1175
1176                         cpt2 = lnet_cpt_of_nid_locked(rtr->lp_nid);
1177                         if (cpt != cpt2) {
1178                                 lnet_net_unlock(cpt);
1179                                 cpt = cpt2;
1180                                 lnet_net_lock(cpt);
1181                                 /* the routers list has changed */
1182                                 if (version != the_lnet.ln_routers_version)
1183                                         goto rescan;
1184                         }
1185
1186                         lnet_ping_router_locked(rtr);
1187
1188                         /* NB dropped lock */
1189                         if (version != the_lnet.ln_routers_version) {
1190                                 /* the routers list has changed */
1191                                 goto rescan;
1192                         }
1193                 }
1194
1195                 if (the_lnet.ln_routing)
1196                         lnet_update_ni_status_locked();
1197
1198                 lnet_net_unlock(cpt);
1199
1200                 lnet_prune_rc_data(0); /* don't wait for UNLINK */
1201
1202                 /* Call schedule_timeout() here always adds 1 to load average
1203                  * because kernel counts # active tasks as nr_running
1204                  * + nr_uninterruptible. */
1205                 set_current_state(TASK_INTERRUPTIBLE);
1206                 schedule_timeout(cfs_time_seconds(1));
1207         }
1208
1209         LASSERT(the_lnet.ln_rc_state == LNET_RC_STATE_STOPPING);
1210
1211         lnet_prune_rc_data(1); /* wait for UNLINK */
1212
1213         the_lnet.ln_rc_state = LNET_RC_STATE_SHUTDOWN;
1214         up(&the_lnet.ln_rc_signal);
1215         /* The unlink event callback will signal final completion */
1216         return 0;
1217 }
1218
1219 static void
1220 lnet_destroy_rtrbuf(lnet_rtrbuf_t *rb, int npages)
1221 {
1222         int sz = offsetof(lnet_rtrbuf_t, rb_kiov[npages]);
1223
1224         while (--npages >= 0)
1225                 __free_page(rb->rb_kiov[npages].kiov_page);
1226
1227         LIBCFS_FREE(rb, sz);
1228 }
1229
1230 static lnet_rtrbuf_t *
1231 lnet_new_rtrbuf(lnet_rtrbufpool_t *rbp, int cpt)
1232 {
1233         int npages = rbp->rbp_npages;
1234         int sz = offsetof(lnet_rtrbuf_t, rb_kiov[npages]);
1235         struct page *page;
1236         lnet_rtrbuf_t *rb;
1237         int i;
1238
1239         LIBCFS_CPT_ALLOC(rb, lnet_cpt_table(), cpt, sz);
1240         if (rb == NULL)
1241                 return NULL;
1242
1243         rb->rb_pool = rbp;
1244
1245         for (i = 0; i < npages; i++) {
1246                 page = alloc_pages_node(
1247                                 cfs_cpt_spread_node(lnet_cpt_table(), cpt),
1248                                 GFP_KERNEL | __GFP_ZERO, 0);
1249                 if (page == NULL) {
1250                         while (--i >= 0)
1251                                 __free_page(rb->rb_kiov[i].kiov_page);
1252
1253                         LIBCFS_FREE(rb, sz);
1254                         return NULL;
1255                 }
1256
1257                 rb->rb_kiov[i].kiov_len = PAGE_CACHE_SIZE;
1258                 rb->rb_kiov[i].kiov_offset = 0;
1259                 rb->rb_kiov[i].kiov_page = page;
1260         }
1261
1262         return rb;
1263 }
1264
1265 static void
1266 lnet_rtrpool_free_bufs(lnet_rtrbufpool_t *rbp)
1267 {
1268         int npages = rbp->rbp_npages;
1269         int nbuffers = 0;
1270         lnet_rtrbuf_t *rb;
1271
1272         if (rbp->rbp_nbuffers == 0) /* not initialized or already freed */
1273                 return;
1274
1275         LASSERT(list_empty(&rbp->rbp_msgs));
1276         LASSERT(rbp->rbp_credits == rbp->rbp_nbuffers);
1277
1278         while (!list_empty(&rbp->rbp_bufs)) {
1279                 LASSERT(rbp->rbp_credits > 0);
1280
1281                 rb = list_entry(rbp->rbp_bufs.next,
1282                                     lnet_rtrbuf_t, rb_list);
1283                 list_del(&rb->rb_list);
1284                 lnet_destroy_rtrbuf(rb, npages);
1285                 nbuffers++;
1286         }
1287
1288         LASSERT(rbp->rbp_nbuffers == nbuffers);
1289         LASSERT(rbp->rbp_credits == nbuffers);
1290
1291         rbp->rbp_nbuffers = rbp->rbp_credits = 0;
1292 }
1293
1294 static int
1295 lnet_rtrpool_alloc_bufs(lnet_rtrbufpool_t *rbp, int nbufs, int cpt)
1296 {
1297         lnet_rtrbuf_t *rb;
1298         int i;
1299
1300         if (rbp->rbp_nbuffers != 0) {
1301                 LASSERT(rbp->rbp_nbuffers == nbufs);
1302                 return 0;
1303         }
1304
1305         for (i = 0; i < nbufs; i++) {
1306                 rb = lnet_new_rtrbuf(rbp, cpt);
1307
1308                 if (rb == NULL) {
1309                         CERROR("Failed to allocate %d router bufs of %d pages\n",
1310                                nbufs, rbp->rbp_npages);
1311                         return -ENOMEM;
1312                 }
1313
1314                 rbp->rbp_nbuffers++;
1315                 rbp->rbp_credits++;
1316                 rbp->rbp_mincredits++;
1317                 list_add(&rb->rb_list, &rbp->rbp_bufs);
1318
1319                 /* No allocation "under fire" */
1320                 /* Otherwise we'd need code to schedule blocked msgs etc */
1321                 LASSERT(!the_lnet.ln_routing);
1322         }
1323
1324         LASSERT(rbp->rbp_credits == nbufs);
1325         return 0;
1326 }
1327
1328 static void
1329 lnet_rtrpool_init(lnet_rtrbufpool_t *rbp, int npages)
1330 {
1331         INIT_LIST_HEAD(&rbp->rbp_msgs);
1332         INIT_LIST_HEAD(&rbp->rbp_bufs);
1333
1334         rbp->rbp_npages = npages;
1335         rbp->rbp_credits = 0;
1336         rbp->rbp_mincredits = 0;
1337 }
1338
1339 void
1340 lnet_rtrpools_free(void)
1341 {
1342         lnet_rtrbufpool_t *rtrp;
1343         int i;
1344
1345         if (the_lnet.ln_rtrpools == NULL) /* uninitialized or freed */
1346                 return;
1347
1348         cfs_percpt_for_each(rtrp, i, the_lnet.ln_rtrpools) {
1349                 lnet_rtrpool_free_bufs(&rtrp[0]);
1350                 lnet_rtrpool_free_bufs(&rtrp[1]);
1351                 lnet_rtrpool_free_bufs(&rtrp[2]);
1352         }
1353
1354         cfs_percpt_free(the_lnet.ln_rtrpools);
1355         the_lnet.ln_rtrpools = NULL;
1356 }
1357
1358 static int
1359 lnet_nrb_tiny_calculate(int npages)
1360 {
1361         int nrbs = LNET_NRB_TINY;
1362
1363         if (tiny_router_buffers < 0) {
1364                 LCONSOLE_ERROR_MSG(0x10c,
1365                                    "tiny_router_buffers=%d invalid when routing enabled\n",
1366                                    tiny_router_buffers);
1367                 return -1;
1368         }
1369
1370         if (tiny_router_buffers > 0)
1371                 nrbs = tiny_router_buffers;
1372
1373         nrbs /= LNET_CPT_NUMBER;
1374         return max(nrbs, LNET_NRB_TINY_MIN);
1375 }
1376
1377 static int
1378 lnet_nrb_small_calculate(int npages)
1379 {
1380         int nrbs = LNET_NRB_SMALL;
1381
1382         if (small_router_buffers < 0) {
1383                 LCONSOLE_ERROR_MSG(0x10c,
1384                                    "small_router_buffers=%d invalid when routing enabled\n",
1385                                    small_router_buffers);
1386                 return -1;
1387         }
1388
1389         if (small_router_buffers > 0)
1390                 nrbs = small_router_buffers;
1391
1392         nrbs /= LNET_CPT_NUMBER;
1393         return max(nrbs, LNET_NRB_SMALL_MIN);
1394 }
1395
1396 static int
1397 lnet_nrb_large_calculate(int npages)
1398 {
1399         int nrbs = LNET_NRB_LARGE;
1400
1401         if (large_router_buffers < 0) {
1402                 LCONSOLE_ERROR_MSG(0x10c,
1403                                    "large_router_buffers=%d invalid when routing enabled\n",
1404                                    large_router_buffers);
1405                 return -1;
1406         }
1407
1408         if (large_router_buffers > 0)
1409                 nrbs = large_router_buffers;
1410
1411         nrbs /= LNET_CPT_NUMBER;
1412         return max(nrbs, LNET_NRB_LARGE_MIN);
1413 }
1414
1415 int
1416 lnet_rtrpools_alloc(int im_a_router)
1417 {
1418         lnet_rtrbufpool_t *rtrp;
1419         int large_pages;
1420         int small_pages = 1;
1421         int nrb_tiny;
1422         int nrb_small;
1423         int nrb_large;
1424         int rc;
1425         int i;
1426
1427         large_pages = (LNET_MTU + PAGE_CACHE_SIZE - 1) >> PAGE_CACHE_SHIFT;
1428
1429         if (!strcmp(forwarding, "")) {
1430                 /* not set either way */
1431                 if (!im_a_router)
1432                         return 0;
1433         } else if (!strcmp(forwarding, "disabled")) {
1434                 /* explicitly disabled */
1435                 return 0;
1436         } else if (!strcmp(forwarding, "enabled")) {
1437                 /* explicitly enabled */
1438         } else {
1439                 LCONSOLE_ERROR_MSG(0x10b, "'forwarding' not set to either 'enabled' or 'disabled'\n");
1440                 return -EINVAL;
1441         }
1442
1443         nrb_tiny = lnet_nrb_tiny_calculate(0);
1444         if (nrb_tiny < 0)
1445                 return -EINVAL;
1446
1447         nrb_small = lnet_nrb_small_calculate(small_pages);
1448         if (nrb_small < 0)
1449                 return -EINVAL;
1450
1451         nrb_large = lnet_nrb_large_calculate(large_pages);
1452         if (nrb_large < 0)
1453                 return -EINVAL;
1454
1455         the_lnet.ln_rtrpools = cfs_percpt_alloc(lnet_cpt_table(),
1456                                                 LNET_NRBPOOLS *
1457                                                 sizeof(lnet_rtrbufpool_t));
1458         if (the_lnet.ln_rtrpools == NULL) {
1459                 LCONSOLE_ERROR_MSG(0x10c,
1460                                    "Failed to initialize router buffe pool\n");
1461                 return -ENOMEM;
1462         }
1463
1464         cfs_percpt_for_each(rtrp, i, the_lnet.ln_rtrpools) {
1465                 lnet_rtrpool_init(&rtrp[0], 0);
1466                 rc = lnet_rtrpool_alloc_bufs(&rtrp[0], nrb_tiny, i);
1467                 if (rc != 0)
1468                         goto failed;
1469
1470                 lnet_rtrpool_init(&rtrp[1], small_pages);
1471                 rc = lnet_rtrpool_alloc_bufs(&rtrp[1], nrb_small, i);
1472                 if (rc != 0)
1473                         goto failed;
1474
1475                 lnet_rtrpool_init(&rtrp[2], large_pages);
1476                 rc = lnet_rtrpool_alloc_bufs(&rtrp[2], nrb_large, i);
1477                 if (rc != 0)
1478                         goto failed;
1479         }
1480
1481         lnet_net_lock(LNET_LOCK_EX);
1482         the_lnet.ln_routing = 1;
1483         lnet_net_unlock(LNET_LOCK_EX);
1484
1485         return 0;
1486
1487  failed:
1488         lnet_rtrpools_free();
1489         return rc;
1490 }
1491
1492 int
1493 lnet_notify(lnet_ni_t *ni, lnet_nid_t nid, int alive, unsigned long when)
1494 {
1495         struct lnet_peer *lp = NULL;
1496         unsigned long now = cfs_time_current();
1497         int cpt = lnet_cpt_of_nid(nid);
1498
1499         LASSERT(!in_interrupt());
1500
1501         CDEBUG(D_NET, "%s notifying %s: %s\n",
1502                 (ni == NULL) ? "userspace" : libcfs_nid2str(ni->ni_nid),
1503                 libcfs_nid2str(nid),
1504                 alive ? "up" : "down");
1505
1506         if (ni != NULL &&
1507             LNET_NIDNET(ni->ni_nid) != LNET_NIDNET(nid)) {
1508                 CWARN("Ignoring notification of %s %s by %s (different net)\n",
1509                         libcfs_nid2str(nid), alive ? "birth" : "death",
1510                         libcfs_nid2str(ni->ni_nid));
1511                 return -EINVAL;
1512         }
1513
1514         /* can't do predictions... */
1515         if (cfs_time_after(when, now)) {
1516                 CWARN("Ignoring prediction from %s of %s %s %ld seconds in the future\n",
1517                       (ni == NULL) ? "userspace" : libcfs_nid2str(ni->ni_nid),
1518                       libcfs_nid2str(nid), alive ? "up" : "down",
1519                       cfs_duration_sec(cfs_time_sub(when, now)));
1520                 return -EINVAL;
1521         }
1522
1523         if (ni != NULL && !alive &&          /* LND telling me she's down */
1524             !auto_down) {                      /* auto-down disabled */
1525                 CDEBUG(D_NET, "Auto-down disabled\n");
1526                 return 0;
1527         }
1528
1529         lnet_net_lock(cpt);
1530
1531         if (the_lnet.ln_shutdown) {
1532                 lnet_net_unlock(cpt);
1533                 return -ESHUTDOWN;
1534         }
1535
1536         lp = lnet_find_peer_locked(the_lnet.ln_peer_tables[cpt], nid);
1537         if (lp == NULL) {
1538                 /* nid not found */
1539                 lnet_net_unlock(cpt);
1540                 CDEBUG(D_NET, "%s not found\n", libcfs_nid2str(nid));
1541                 return 0;
1542         }
1543
1544         /* We can't fully trust LND on reporting exact peer last_alive
1545          * if he notifies us about dead peer. For example ksocklnd can
1546          * call us with when == _time_when_the_node_was_booted_ if
1547          * no connections were successfully established */
1548         if (ni != NULL && !alive && when < lp->lp_last_alive)
1549                 when = lp->lp_last_alive;
1550
1551         lnet_notify_locked(lp, ni == NULL, alive, when);
1552
1553         lnet_ni_notify_locked(ni, lp);
1554
1555         lnet_peer_decref_locked(lp);
1556
1557         lnet_net_unlock(cpt);
1558         return 0;
1559 }
1560 EXPORT_SYMBOL(lnet_notify);