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, 2015, 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  */
  19
  20 #define DEBUG_SUBSYSTEM S_LNET
  21 #include <linux/completion.h>
  22 #include "../../include/linux/lnet/lib-lnet.h"
  23
  24 #define LNET_NRB_TINY_MIN       512     /* min value for each CPT */
  25 #define LNET_NRB_TINY           (LNET_NRB_TINY_MIN * 4)
  26 #define LNET_NRB_SMALL_MIN      4096    /* min value for each CPT */
  27 #define LNET_NRB_SMALL          (LNET_NRB_SMALL_MIN * 4)
  28 #define LNET_NRB_SMALL_PAGES    1
  29 #define LNET_NRB_LARGE_MIN      256     /* min value for each CPT */
  30 #define LNET_NRB_LARGE          (LNET_NRB_LARGE_MIN * 4)
  31 #define LNET_NRB_LARGE_PAGES   ((LNET_MTU + PAGE_SIZE - 1) >> \
  32                                  PAGE_SHIFT)
  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         /*
  65          * As an approximation, allow this peer the same number of router
  66          * buffers as it is allowed outstanding sends
  67          */
  68         return ni->ni_peertxcredits;
  69 }
  70
  71 /* forward ref's */
  72 static int lnet_router_checker(void *);
  73
  74 static int check_routers_before_use;
  75 module_param(check_routers_before_use, int, 0444);
  76 MODULE_PARM_DESC(check_routers_before_use, "Assume routers are down and ping them before use");
  77
  78 int avoid_asym_router_failure = 1;
  79 module_param(avoid_asym_router_failure, int, 0644);
  80 MODULE_PARM_DESC(avoid_asym_router_failure, "Avoid asymmetrical router failures (0 to disable)");
  81
  82 static int dead_router_check_interval = 60;
  83 module_param(dead_router_check_interval, int, 0644);
  84 MODULE_PARM_DESC(dead_router_check_interval, "Seconds between dead router health checks (<= 0 to disable)");
  85
  86 static int live_router_check_interval = 60;
  87 module_param(live_router_check_interval, int, 0644);
  88 MODULE_PARM_DESC(live_router_check_interval, "Seconds between live router health checks (<= 0 to disable)");
  89
  90 static int router_ping_timeout = 50;
  91 module_param(router_ping_timeout, int, 0644);
  92 MODULE_PARM_DESC(router_ping_timeout, "Seconds to wait for the reply to a router health query");
  93
  94 int
  95 lnet_peers_start_down(void)
  96 {
  97         return check_routers_before_use;
  98 }
  99
 100 void
 101 lnet_notify_locked(lnet_peer_t *lp, int notifylnd, int alive,
 102                    unsigned long when)
 103 {
 104         if (time_before(when, lp->lp_timestamp)) { /* out of date information */
 105                 CDEBUG(D_NET, "Out of date\n");
 106                 return;
 107         }
 108
 109         lp->lp_timestamp = when;                /* update timestamp */
 110         lp->lp_ping_deadline = 0;              /* disable ping timeout */
 111
 112         if (lp->lp_alive_count &&         /* got old news */
 113             (!lp->lp_alive) == (!alive)) {      /* new date for old news */
 114                 CDEBUG(D_NET, "Old news\n");
 115                 return;
 116         }
 117
 118         /* Flag that notification is outstanding */
 119
 120         lp->lp_alive_count++;
 121         lp->lp_alive = !(!alive);              /* 1 bit! */
 122         lp->lp_notify = 1;
 123         lp->lp_notifylnd |= notifylnd;
 124         if (lp->lp_alive)
 125                 lp->lp_ping_feats = LNET_PING_FEAT_INVAL; /* reset */
 126
 127         CDEBUG(D_NET, "set %s %d\n", libcfs_nid2str(lp->lp_nid), alive);
 128 }
 129
 130 static void
 131 lnet_ni_notify_locked(lnet_ni_t *ni, lnet_peer_t *lp)
 132 {
 133         int alive;
 134         int notifylnd;
 135
 136         /*
 137          * Notify only in 1 thread at any time to ensure ordered notification.
 138          * NB individual events can be missed; the only guarantee is that you
 139          * always get the most recent news
 140          */
 141         if (lp->lp_notifying || !ni)
 142                 return;
 143
 144         lp->lp_notifying = 1;
 145
 146         while (lp->lp_notify) {
 147                 alive = lp->lp_alive;
 148                 notifylnd = lp->lp_notifylnd;
 149
 150                 lp->lp_notifylnd = 0;
 151                 lp->lp_notify    = 0;
 152
 153                 if (notifylnd && ni->ni_lnd->lnd_notify) {
 154                         lnet_net_unlock(lp->lp_cpt);
 155
 156                         /*
 157                          * A new notification could happen now; I'll handle it
 158                          * when control returns to me
 159                          */
 160                         ni->ni_lnd->lnd_notify(ni, lp->lp_nid, alive);
 161
 162                         lnet_net_lock(lp->lp_cpt);
 163                 }
 164         }
 165
 166         lp->lp_notifying = 0;
 167 }
 168
 169 static void
 170 lnet_rtr_addref_locked(lnet_peer_t *lp)
 171 {
 172         LASSERT(lp->lp_refcount > 0);
 173         LASSERT(lp->lp_rtr_refcount >= 0);
 174
 175         /* lnet_net_lock must be exclusively locked */
 176         lp->lp_rtr_refcount++;
 177         if (lp->lp_rtr_refcount == 1) {
 178                 struct list_head *pos;
 179
 180                 /* a simple insertion sort */
 181                 list_for_each_prev(pos, &the_lnet.ln_routers) {
 182                         lnet_peer_t *rtr = list_entry(pos, lnet_peer_t,
 183                                                       lp_rtr_list);
 184
 185                         if (rtr->lp_nid < lp->lp_nid)
 186                                 break;
 187                 }
 188
 189                 list_add(&lp->lp_rtr_list, pos);
 190                 /* addref for the_lnet.ln_routers */
 191                 lnet_peer_addref_locked(lp);
 192                 the_lnet.ln_routers_version++;
 193         }
 194 }
 195
 196 static void
 197 lnet_rtr_decref_locked(lnet_peer_t *lp)
 198 {
 199         LASSERT(lp->lp_refcount > 0);
 200         LASSERT(lp->lp_rtr_refcount > 0);
 201
 202         /* lnet_net_lock must be exclusively locked */
 203         lp->lp_rtr_refcount--;
 204         if (!lp->lp_rtr_refcount) {
 205                 LASSERT(list_empty(&lp->lp_routes));
 206
 207                 if (lp->lp_rcd) {
 208                         list_add(&lp->lp_rcd->rcd_list,
 209                                  &the_lnet.ln_rcd_deathrow);
 210                         lp->lp_rcd = NULL;
 211                 }
 212
 213                 list_del(&lp->lp_rtr_list);
 214                 /* decref for the_lnet.ln_routers */
 215                 lnet_peer_decref_locked(lp);
 216                 the_lnet.ln_routers_version++;
 217         }
 218 }
 219
 220 lnet_remotenet_t *
 221 lnet_find_net_locked(__u32 net)
 222 {
 223         lnet_remotenet_t *rnet;
 224         struct list_head *tmp;
 225         struct list_head *rn_list;
 226
 227         LASSERT(!the_lnet.ln_shutdown);
 228
 229         rn_list = lnet_net2rnethash(net);
 230         list_for_each(tmp, rn_list) {
 231                 rnet = list_entry(tmp, lnet_remotenet_t, lrn_list);
 232
 233                 if (rnet->lrn_net == net)
 234                         return rnet;
 235         }
 236         return NULL;
 237 }
 238
 239 static void lnet_shuffle_seed(void)
 240 {
 241         static int seeded;
 242         __u32 lnd_type, seed[2];
 243         struct timespec64 ts;
 244         lnet_ni_t *ni;
 245         struct list_head *tmp;
 246
 247         if (seeded)
 248                 return;
 249
 250         cfs_get_random_bytes(seed, sizeof(seed));
 251
 252         /*
 253          * Nodes with small feet have little entropy
 254          * the NID for this node gives the most entropy in the low bits
 255          */
 256         list_for_each(tmp, &the_lnet.ln_nis) {
 257                 ni = list_entry(tmp, lnet_ni_t, ni_list);
 258                 lnd_type = LNET_NETTYP(LNET_NIDNET(ni->ni_nid));
 259
 260                 if (lnd_type != LOLND)
 261                         seed[0] ^= (LNET_NIDADDR(ni->ni_nid) | lnd_type);
 262         }
 263
 264         ktime_get_ts64(&ts);
 265         cfs_srand(ts.tv_sec ^ seed[0], ts.tv_nsec ^ seed[1]);
 266         seeded = 1;
 267 }
 268
 269 /* NB expects LNET_LOCK held */
 270 static void
 271 lnet_add_route_to_rnet(lnet_remotenet_t *rnet, lnet_route_t *route)
 272 {
 273         unsigned int len = 0;
 274         unsigned int offset = 0;
 275         struct list_head *e;
 276
 277         lnet_shuffle_seed();
 278
 279         list_for_each(e, &rnet->lrn_routes) {
 280                 len++;
 281         }
 282
 283         /* len+1 positions to add a new entry, also prevents division by 0 */
 284         offset = cfs_rand() % (len + 1);
 285         list_for_each(e, &rnet->lrn_routes) {
 286                 if (!offset)
 287                         break;
 288                 offset--;
 289         }
 290         list_add(&route->lr_list, e);
 291         list_add(&route->lr_gwlist, &route->lr_gateway->lp_routes);
 292
 293         the_lnet.ln_remote_nets_version++;
 294         lnet_rtr_addref_locked(route->lr_gateway);
 295 }
 296
 297 int
 298 lnet_add_route(__u32 net, __u32 hops, lnet_nid_t gateway,
 299                unsigned int priority)
 300 {
 301         struct list_head *e;
 302         lnet_remotenet_t *rnet;
 303         lnet_remotenet_t *rnet2;
 304         lnet_route_t *route;
 305         lnet_ni_t *ni;
 306         int add_route;
 307         int rc;
 308
 309         CDEBUG(D_NET, "Add route: net %s hops %d priority %u gw %s\n",
 310                libcfs_net2str(net), hops, priority, libcfs_nid2str(gateway));
 311
 312         if (gateway == LNET_NID_ANY ||
 313             LNET_NETTYP(LNET_NIDNET(gateway)) == LOLND ||
 314             net == LNET_NIDNET(LNET_NID_ANY) ||
 315             LNET_NETTYP(net) == LOLND ||
 316             LNET_NIDNET(gateway) == net ||
 317             (hops != LNET_UNDEFINED_HOPS && (hops < 1 || hops > 255)))
 318                 return -EINVAL;
 319
 320         if (lnet_islocalnet(net))              /* it's a local network */
 321                 return -EEXIST;
 322
 323         /* Assume net, route, all new */
 324         LIBCFS_ALLOC(route, sizeof(*route));
 325         LIBCFS_ALLOC(rnet, sizeof(*rnet));
 326         if (!route || !rnet) {
 327                 CERROR("Out of memory creating route %s %d %s\n",
 328                        libcfs_net2str(net), hops, libcfs_nid2str(gateway));
 329                 if (route)
 330                         LIBCFS_FREE(route, sizeof(*route));
 331                 if (rnet)
 332                         LIBCFS_FREE(rnet, sizeof(*rnet));
 333                 return -ENOMEM;
 334         }
 335
 336         INIT_LIST_HEAD(&rnet->lrn_routes);
 337         rnet->lrn_net = net;
 338         route->lr_hops = hops;
 339         route->lr_net = net;
 340         route->lr_priority = priority;
 341
 342         lnet_net_lock(LNET_LOCK_EX);
 343
 344         rc = lnet_nid2peer_locked(&route->lr_gateway, gateway, LNET_LOCK_EX);
 345         if (rc) {
 346                 lnet_net_unlock(LNET_LOCK_EX);
 347
 348                 LIBCFS_FREE(route, sizeof(*route));
 349                 LIBCFS_FREE(rnet, sizeof(*rnet));
 350
 351                 if (rc == -EHOSTUNREACH) /* gateway is not on a local net */
 352                         return rc;      /* ignore the route entry */
 353                 CERROR("Error %d creating route %s %d %s\n", rc,
 354                        libcfs_net2str(net), hops,
 355                        libcfs_nid2str(gateway));
 356                 return rc;
 357         }
 358
 359         LASSERT(!the_lnet.ln_shutdown);
 360
 361         rnet2 = lnet_find_net_locked(net);
 362         if (!rnet2) {
 363                 /* new network */
 364                 list_add_tail(&rnet->lrn_list, lnet_net2rnethash(net));
 365                 rnet2 = rnet;
 366         }
 367
 368         /* Search for a duplicate route (it's a NOOP if it is) */
 369         add_route = 1;
 370         list_for_each(e, &rnet2->lrn_routes) {
 371                 lnet_route_t *route2 = list_entry(e, lnet_route_t, lr_list);
 372
 373                 if (route2->lr_gateway == route->lr_gateway) {
 374                         add_route = 0;
 375                         break;
 376                 }
 377
 378                 /* our lookups must be true */
 379                 LASSERT(route2->lr_gateway->lp_nid != gateway);
 380         }
 381
 382         if (add_route) {
 383                 lnet_peer_addref_locked(route->lr_gateway); /* +1 for notify */
 384                 lnet_add_route_to_rnet(rnet2, route);
 385
 386                 ni = route->lr_gateway->lp_ni;
 387                 lnet_net_unlock(LNET_LOCK_EX);
 388
 389                 /* XXX Assume alive */
 390                 if (ni->ni_lnd->lnd_notify)
 391                         ni->ni_lnd->lnd_notify(ni, gateway, 1);
 392
 393                 lnet_net_lock(LNET_LOCK_EX);
 394         }
 395
 396         /* -1 for notify or !add_route */
 397         lnet_peer_decref_locked(route->lr_gateway);
 398         lnet_net_unlock(LNET_LOCK_EX);
 399         rc = 0;
 400
 401         if (!add_route) {
 402                 rc = -EEXIST;
 403                 LIBCFS_FREE(route, sizeof(*route));
 404         }
 405
 406         if (rnet != rnet2)
 407                 LIBCFS_FREE(rnet, sizeof(*rnet));
 408
 409         /* indicate to startup the router checker if configured */
 410         wake_up(&the_lnet.ln_rc_waitq);
 411
 412         return rc;
 413 }
 414
 415 int
 416 lnet_check_routes(void)
 417 {
 418         lnet_remotenet_t *rnet;
 419         lnet_route_t *route;
 420         lnet_route_t *route2;
 421         struct list_head *e1;
 422         struct list_head *e2;
 423         int cpt;
 424         struct list_head *rn_list;
 425         int i;
 426
 427         cpt = lnet_net_lock_current();
 428
 429         for (i = 0; i < LNET_REMOTE_NETS_HASH_SIZE; i++) {
 430                 rn_list = &the_lnet.ln_remote_nets_hash[i];
 431                 list_for_each(e1, rn_list) {
 432                         rnet = list_entry(e1, lnet_remotenet_t, lrn_list);
 433
 434                         route2 = NULL;
 435                         list_for_each(e2, &rnet->lrn_routes) {
 436                                 lnet_nid_t nid1;
 437                                 lnet_nid_t nid2;
 438                                 int net;
 439
 440                                 route = list_entry(e2, lnet_route_t, lr_list);
 441
 442                                 if (!route2) {
 443                                         route2 = route;
 444                                         continue;
 445                                 }
 446
 447                                 if (route->lr_gateway->lp_ni ==
 448                                     route2->lr_gateway->lp_ni)
 449                                         continue;
 450
 451                                 nid1 = route->lr_gateway->lp_nid;
 452                                 nid2 = route2->lr_gateway->lp_nid;
 453                                 net = rnet->lrn_net;
 454
 455                                 lnet_net_unlock(cpt);
 456
 457                                 CERROR("Routes to %s via %s and %s not supported\n",
 458                                        libcfs_net2str(net),
 459                                        libcfs_nid2str(nid1),
 460                                        libcfs_nid2str(nid2));
 461                                 return -EINVAL;
 462                         }
 463                 }
 464         }
 465
 466         lnet_net_unlock(cpt);
 467         return 0;
 468 }
 469
 470 int
 471 lnet_del_route(__u32 net, lnet_nid_t gw_nid)
 472 {
 473         struct lnet_peer *gateway;
 474         lnet_remotenet_t *rnet;
 475         lnet_route_t *route;
 476         struct list_head *e1;
 477         struct list_head *e2;
 478         int rc = -ENOENT;
 479         struct list_head *rn_list;
 480         int idx = 0;
 481
 482         CDEBUG(D_NET, "Del route: net %s : gw %s\n",
 483                libcfs_net2str(net), libcfs_nid2str(gw_nid));
 484
 485         /*
 486          * NB Caller may specify either all routes via the given gateway
 487          * or a specific route entry actual NIDs)
 488          */
 489         lnet_net_lock(LNET_LOCK_EX);
 490         if (net == LNET_NIDNET(LNET_NID_ANY))
 491                 rn_list = &the_lnet.ln_remote_nets_hash[0];
 492         else
 493                 rn_list = lnet_net2rnethash(net);
 494
 495  again:
 496         list_for_each(e1, rn_list) {
 497                 rnet = list_entry(e1, lnet_remotenet_t, lrn_list);
 498
 499                 if (!(net == LNET_NIDNET(LNET_NID_ANY) ||
 500                       net == rnet->lrn_net))
 501                         continue;
 502
 503                 list_for_each(e2, &rnet->lrn_routes) {
 504                         route = list_entry(e2, lnet_route_t, lr_list);
 505
 506                         gateway = route->lr_gateway;
 507                         if (!(gw_nid == LNET_NID_ANY ||
 508                               gw_nid == gateway->lp_nid))
 509                                 continue;
 510
 511                         list_del(&route->lr_list);
 512                         list_del(&route->lr_gwlist);
 513                         the_lnet.ln_remote_nets_version++;
 514
 515                         if (list_empty(&rnet->lrn_routes))
 516                                 list_del(&rnet->lrn_list);
 517                         else
 518                                 rnet = NULL;
 519
 520                         lnet_rtr_decref_locked(gateway);
 521                         lnet_peer_decref_locked(gateway);
 522
 523                         lnet_net_unlock(LNET_LOCK_EX);
 524
 525                         LIBCFS_FREE(route, sizeof(*route));
 526
 527                         if (rnet)
 528                                 LIBCFS_FREE(rnet, sizeof(*rnet));
 529
 530                         rc = 0;
 531                         lnet_net_lock(LNET_LOCK_EX);
 532                         goto again;
 533                 }
 534         }
 535
 536         if (net == LNET_NIDNET(LNET_NID_ANY) &&
 537             ++idx < LNET_REMOTE_NETS_HASH_SIZE) {
 538                 rn_list = &the_lnet.ln_remote_nets_hash[idx];
 539                 goto again;
 540         }
 541         lnet_net_unlock(LNET_LOCK_EX);
 542
 543         return rc;
 544 }
 545
 546 void
 547 lnet_destroy_routes(void)
 548 {
 549         lnet_del_route(LNET_NIDNET(LNET_NID_ANY), LNET_NID_ANY);
 550 }
 551
 552 int lnet_get_rtr_pool_cfg(int idx, struct lnet_ioctl_pool_cfg *pool_cfg)
 553 {
 554         int i, rc = -ENOENT, j;
 555
 556         if (!the_lnet.ln_rtrpools)
 557                 return rc;
 558
 559         for (i = 0; i < LNET_NRBPOOLS; i++) {
 560                 lnet_rtrbufpool_t *rbp;
 561
 562                 lnet_net_lock(LNET_LOCK_EX);
 563                 cfs_percpt_for_each(rbp, j, the_lnet.ln_rtrpools) {
 564                         if (i++ != idx)
 565                                 continue;
 566
 567                         pool_cfg->pl_pools[i].pl_npages = rbp[i].rbp_npages;
 568                         pool_cfg->pl_pools[i].pl_nbuffers = rbp[i].rbp_nbuffers;
 569                         pool_cfg->pl_pools[i].pl_credits = rbp[i].rbp_credits;
 570                         pool_cfg->pl_pools[i].pl_mincredits = rbp[i].rbp_mincredits;
 571                         rc = 0;
 572                         break;
 573                 }
 574                 lnet_net_unlock(LNET_LOCK_EX);
 575         }
 576
 577         lnet_net_lock(LNET_LOCK_EX);
 578         pool_cfg->pl_routing = the_lnet.ln_routing;
 579         lnet_net_unlock(LNET_LOCK_EX);
 580
 581         return rc;
 582 }
 583
 584 int
 585 lnet_get_route(int idx, __u32 *net, __u32 *hops,
 586                lnet_nid_t *gateway, __u32 *alive, __u32 *priority)
 587 {
 588         struct list_head *e1;
 589         struct list_head *e2;
 590         lnet_remotenet_t *rnet;
 591         lnet_route_t *route;
 592         int cpt;
 593         int i;
 594         struct list_head *rn_list;
 595
 596         cpt = lnet_net_lock_current();
 597
 598         for (i = 0; i < LNET_REMOTE_NETS_HASH_SIZE; i++) {
 599                 rn_list = &the_lnet.ln_remote_nets_hash[i];
 600                 list_for_each(e1, rn_list) {
 601                         rnet = list_entry(e1, lnet_remotenet_t, lrn_list);
 602
 603                         list_for_each(e2, &rnet->lrn_routes) {
 604                                 route = list_entry(e2, lnet_route_t, lr_list);
 605
 606                                 if (!idx--) {
 607                                         *net      = rnet->lrn_net;
 608                                         *hops     = route->lr_hops;
 609                                         *priority = route->lr_priority;
 610                                         *gateway  = route->lr_gateway->lp_nid;
 611                                         *alive = lnet_is_route_alive(route);
 612                                         lnet_net_unlock(cpt);
 613                                         return 0;
 614                                 }
 615                         }
 616                 }
 617         }
 618
 619         lnet_net_unlock(cpt);
 620         return -ENOENT;
 621 }
 622
 623 void
 624 lnet_swap_pinginfo(lnet_ping_info_t *info)
 625 {
 626         int i;
 627         lnet_ni_status_t *stat;
 628
 629         __swab32s(&info->pi_magic);
 630         __swab32s(&info->pi_features);
 631         __swab32s(&info->pi_pid);
 632         __swab32s(&info->pi_nnis);
 633         for (i = 0; i < info->pi_nnis && i < LNET_MAX_RTR_NIS; i++) {
 634                 stat = &info->pi_ni[i];
 635                 __swab64s(&stat->ns_nid);
 636                 __swab32s(&stat->ns_status);
 637         }
 638 }
 639
 640 /**
 641  * parse router-checker pinginfo, record number of down NIs for remote
 642  * networks on that router.
 643  */
 644 static void
 645 lnet_parse_rc_info(lnet_rc_data_t *rcd)
 646 {
 647         lnet_ping_info_t *info = rcd->rcd_pinginfo;
 648         struct lnet_peer *gw = rcd->rcd_gateway;
 649         lnet_route_t *rte;
 650
 651         if (!gw->lp_alive)
 652                 return;
 653
 654         if (info->pi_magic == __swab32(LNET_PROTO_PING_MAGIC))
 655                 lnet_swap_pinginfo(info);
 656
 657         /* NB always racing with network! */
 658         if (info->pi_magic != LNET_PROTO_PING_MAGIC) {
 659                 CDEBUG(D_NET, "%s: Unexpected magic %08x\n",
 660                        libcfs_nid2str(gw->lp_nid), info->pi_magic);
 661                 gw->lp_ping_feats = LNET_PING_FEAT_INVAL;
 662                 return;
 663         }
 664
 665         gw->lp_ping_feats = info->pi_features;
 666         if (!(gw->lp_ping_feats & LNET_PING_FEAT_MASK)) {
 667                 CDEBUG(D_NET, "%s: Unexpected features 0x%x\n",
 668                        libcfs_nid2str(gw->lp_nid), gw->lp_ping_feats);
 669                 return; /* nothing I can understand */
 670         }
 671
 672         if (!(gw->lp_ping_feats & LNET_PING_FEAT_NI_STATUS))
 673                 return; /* can't carry NI status info */
 674
 675         list_for_each_entry(rte, &gw->lp_routes, lr_gwlist) {
 676                 int down = 0;
 677                 int up = 0;
 678                 int i;
 679
 680                 if (gw->lp_ping_feats & LNET_PING_FEAT_RTE_DISABLED) {
 681                         rte->lr_downis = 1;
 682                         continue;
 683                 }
 684
 685                 for (i = 0; i < info->pi_nnis && i < LNET_MAX_RTR_NIS; i++) {
 686                         lnet_ni_status_t *stat = &info->pi_ni[i];
 687                         lnet_nid_t nid = stat->ns_nid;
 688
 689                         if (nid == LNET_NID_ANY) {
 690                                 CDEBUG(D_NET, "%s: unexpected LNET_NID_ANY\n",
 691                                        libcfs_nid2str(gw->lp_nid));
 692                                 gw->lp_ping_feats = LNET_PING_FEAT_INVAL;
 693                                 return;
 694                         }
 695
 696                         if (LNET_NETTYP(LNET_NIDNET(nid)) == LOLND)
 697                                 continue;
 698
 699                         if (stat->ns_status == LNET_NI_STATUS_DOWN) {
 700                                 down++;
 701                                 continue;
 702                         }
 703
 704                         if (stat->ns_status == LNET_NI_STATUS_UP) {
 705                                 if (LNET_NIDNET(nid) == rte->lr_net) {
 706                                         up = 1;
 707                                         break;
 708                                 }
 709                                 continue;
 710                         }
 711
 712                         CDEBUG(D_NET, "%s: Unexpected status 0x%x\n",
 713                                libcfs_nid2str(gw->lp_nid), stat->ns_status);
 714                         gw->lp_ping_feats = LNET_PING_FEAT_INVAL;
 715                         return;
 716                 }
 717
 718                 if (up) { /* ignore downed NIs if NI for dest network is up */
 719                         rte->lr_downis = 0;
 720                         continue;
 721                 }
 722                 /**
 723                  * if @down is zero and this route is single-hop, it means
 724                  * we can't find NI for target network
 725                  */
 726                 if (!down && rte->lr_hops == 1)
 727                         down = 1;
 728
 729                 rte->lr_downis = down;
 730         }
 731 }
 732
 733 static void
 734 lnet_router_checker_event(lnet_event_t *event)
 735 {
 736         lnet_rc_data_t *rcd = event->md.user_ptr;
 737         struct lnet_peer *lp;
 738
 739         LASSERT(rcd);
 740
 741         if (event->unlinked) {
 742                 LNetInvalidateHandle(&rcd->rcd_mdh);
 743                 return;
 744         }
 745
 746         LASSERT(event->type == LNET_EVENT_SEND ||
 747                 event->type == LNET_EVENT_REPLY);
 748
 749         lp = rcd->rcd_gateway;
 750         LASSERT(lp);
 751
 752         /*
 753          * NB: it's called with holding lnet_res_lock, we have a few
 754          * places need to hold both locks at the same time, please take
 755          * care of lock ordering
 756          */
 757         lnet_net_lock(lp->lp_cpt);
 758         if (!lnet_isrouter(lp) || lp->lp_rcd != rcd) {
 759                 /* ignore if no longer a router or rcd is replaced */
 760                 goto out;
 761         }
 762
 763         if (event->type == LNET_EVENT_SEND) {
 764                 lp->lp_ping_notsent = 0;
 765                 if (!event->status)
 766                         goto out;
 767         }
 768
 769         /* LNET_EVENT_REPLY */
 770         /*
 771          * A successful REPLY means the router is up.  If _any_ comms
 772          * to the router fail I assume it's down (this will happen if
 773          * we ping alive routers to try to detect router death before
 774          * apps get burned).
 775          */
 776         lnet_notify_locked(lp, 1, !event->status, cfs_time_current());
 777
 778         /*
 779          * The router checker will wake up very shortly and do the
 780          * actual notification.
 781          * XXX If 'lp' stops being a router before then, it will still
 782          * have the notification pending!!!
 783          */
 784         if (avoid_asym_router_failure && !event->status)
 785                 lnet_parse_rc_info(rcd);
 786
 787  out:
 788         lnet_net_unlock(lp->lp_cpt);
 789 }
 790
 791 static void
 792 lnet_wait_known_routerstate(void)
 793 {
 794         lnet_peer_t *rtr;
 795         struct list_head *entry;
 796         int all_known;
 797
 798         LASSERT(the_lnet.ln_rc_state == LNET_RC_STATE_RUNNING);
 799
 800         for (;;) {
 801                 int cpt = lnet_net_lock_current();
 802
 803                 all_known = 1;
 804                 list_for_each(entry, &the_lnet.ln_routers) {
 805                         rtr = list_entry(entry, lnet_peer_t, lp_rtr_list);
 806
 807                         if (!rtr->lp_alive_count) {
 808                                 all_known = 0;
 809                                 break;
 810                         }
 811                 }
 812
 813                 lnet_net_unlock(cpt);
 814
 815                 if (all_known)
 816                         return;
 817
 818                 set_current_state(TASK_UNINTERRUPTIBLE);
 819                 schedule_timeout(cfs_time_seconds(1));
 820         }
 821 }
 822
 823 void
 824 lnet_router_ni_update_locked(lnet_peer_t *gw, __u32 net)
 825 {
 826         lnet_route_t *rte;
 827
 828         if ((gw->lp_ping_feats & LNET_PING_FEAT_NI_STATUS)) {
 829                 list_for_each_entry(rte, &gw->lp_routes, lr_gwlist) {
 830                         if (rte->lr_net == net) {
 831                                 rte->lr_downis = 0;
 832                                 break;
 833                         }
 834                 }
 835         }
 836 }
 837
 838 static void
 839 lnet_update_ni_status_locked(void)
 840 {
 841         lnet_ni_t *ni;
 842         time64_t now;
 843         int timeout;
 844
 845         LASSERT(the_lnet.ln_routing);
 846
 847         timeout = router_ping_timeout +
 848                   max(live_router_check_interval, dead_router_check_interval);
 849
 850         now = ktime_get_real_seconds();
 851         list_for_each_entry(ni, &the_lnet.ln_nis, ni_list) {
 852                 if (ni->ni_lnd->lnd_type == LOLND)
 853                         continue;
 854
 855                 if (now < ni->ni_last_alive + timeout)
 856                         continue;
 857
 858                 lnet_ni_lock(ni);
 859                 /* re-check with lock */
 860                 if (now < ni->ni_last_alive + timeout) {
 861                         lnet_ni_unlock(ni);
 862                         continue;
 863                 }
 864
 865                 LASSERT(ni->ni_status);
 866
 867                 if (ni->ni_status->ns_status != LNET_NI_STATUS_DOWN) {
 868                         CDEBUG(D_NET, "NI(%s:%d) status changed to down\n",
 869                                libcfs_nid2str(ni->ni_nid), timeout);
 870                         /*
 871                          * NB: so far, this is the only place to set
 872                          * NI status to "down"
 873                          */
 874                         ni->ni_status->ns_status = LNET_NI_STATUS_DOWN;
 875                 }
 876                 lnet_ni_unlock(ni);
 877         }
 878 }
 879
 880 static void
 881 lnet_destroy_rc_data(lnet_rc_data_t *rcd)
 882 {
 883         LASSERT(list_empty(&rcd->rcd_list));
 884         /* detached from network */
 885         LASSERT(LNetHandleIsInvalid(rcd->rcd_mdh));
 886
 887         if (rcd->rcd_gateway) {
 888                 int cpt = rcd->rcd_gateway->lp_cpt;
 889
 890                 lnet_net_lock(cpt);
 891                 lnet_peer_decref_locked(rcd->rcd_gateway);
 892                 lnet_net_unlock(cpt);
 893         }
 894
 895         if (rcd->rcd_pinginfo)
 896                 LIBCFS_FREE(rcd->rcd_pinginfo, LNET_PINGINFO_SIZE);
 897
 898         LIBCFS_FREE(rcd, sizeof(*rcd));
 899 }
 900
 901 static lnet_rc_data_t *
 902 lnet_create_rc_data_locked(lnet_peer_t *gateway)
 903 {
 904         lnet_rc_data_t *rcd = NULL;
 905         lnet_ping_info_t *pi;
 906         int rc;
 907         int i;
 908
 909         lnet_net_unlock(gateway->lp_cpt);
 910
 911         LIBCFS_ALLOC(rcd, sizeof(*rcd));
 912         if (!rcd)
 913                 goto out;
 914
 915         LNetInvalidateHandle(&rcd->rcd_mdh);
 916         INIT_LIST_HEAD(&rcd->rcd_list);
 917
 918         LIBCFS_ALLOC(pi, LNET_PINGINFO_SIZE);
 919         if (!pi)
 920                 goto out;
 921
 922         for (i = 0; i < LNET_MAX_RTR_NIS; i++) {
 923                 pi->pi_ni[i].ns_nid = LNET_NID_ANY;
 924                 pi->pi_ni[i].ns_status = LNET_NI_STATUS_INVALID;
 925         }
 926         rcd->rcd_pinginfo = pi;
 927
 928         LASSERT(!LNetHandleIsInvalid(the_lnet.ln_rc_eqh));
 929         rc = LNetMDBind((lnet_md_t){.start     = pi,
 930                                     .user_ptr  = rcd,
 931                                     .length    = LNET_PINGINFO_SIZE,
 932                                     .threshold = LNET_MD_THRESH_INF,
 933                                     .options   = LNET_MD_TRUNCATE,
 934                                     .eq_handle = the_lnet.ln_rc_eqh},
 935                         LNET_UNLINK,
 936                         &rcd->rcd_mdh);
 937         if (rc < 0) {
 938                 CERROR("Can't bind MD: %d\n", rc);
 939                 goto out;
 940         }
 941         LASSERT(!rc);
 942
 943         lnet_net_lock(gateway->lp_cpt);
 944         /* router table changed or someone has created rcd for this gateway */
 945         if (!lnet_isrouter(gateway) || gateway->lp_rcd) {
 946                 lnet_net_unlock(gateway->lp_cpt);
 947                 goto out;
 948         }
 949
 950         lnet_peer_addref_locked(gateway);
 951         rcd->rcd_gateway = gateway;
 952         gateway->lp_rcd = rcd;
 953         gateway->lp_ping_notsent = 0;
 954
 955         return rcd;
 956
 957  out:
 958         if (rcd) {
 959                 if (!LNetHandleIsInvalid(rcd->rcd_mdh)) {
 960                         rc = LNetMDUnlink(rcd->rcd_mdh);
 961                         LASSERT(!rc);
 962                 }
 963                 lnet_destroy_rc_data(rcd);
 964         }
 965
 966         lnet_net_lock(gateway->lp_cpt);
 967         return gateway->lp_rcd;
 968 }
 969
 970 static int
 971 lnet_router_check_interval(lnet_peer_t *rtr)
 972 {
 973         int secs;
 974
 975         secs = rtr->lp_alive ? live_router_check_interval :
 976                                dead_router_check_interval;
 977         if (secs < 0)
 978                 secs = 0;
 979
 980         return secs;
 981 }
 982
 983 static void
 984 lnet_ping_router_locked(lnet_peer_t *rtr)
 985 {
 986         lnet_rc_data_t *rcd = NULL;
 987         unsigned long now = cfs_time_current();
 988         int secs;
 989
 990         lnet_peer_addref_locked(rtr);
 991
 992         if (rtr->lp_ping_deadline && /* ping timed out? */
 993             cfs_time_after(now, rtr->lp_ping_deadline))
 994                 lnet_notify_locked(rtr, 1, 0, now);
 995
 996         /* Run any outstanding notifications */
 997         lnet_ni_notify_locked(rtr->lp_ni, rtr);
 998
 999         if (!lnet_isrouter(rtr) ||
1000             the_lnet.ln_rc_state != LNET_RC_STATE_RUNNING) {
1001                 /* router table changed or router checker is shutting down */
1002                 lnet_peer_decref_locked(rtr);
1003                 return;
1004         }
1005
1006         rcd = rtr->lp_rcd ?
1007               rtr->lp_rcd : lnet_create_rc_data_locked(rtr);
1008
1009         if (!rcd)
1010                 return;
1011
1012         secs = lnet_router_check_interval(rtr);
1013
1014         CDEBUG(D_NET,
1015                "rtr %s %d: deadline %lu ping_notsent %d alive %d alive_count %d lp_ping_timestamp %lu\n",
1016                libcfs_nid2str(rtr->lp_nid), secs,
1017                rtr->lp_ping_deadline, rtr->lp_ping_notsent,
1018                rtr->lp_alive, rtr->lp_alive_count, rtr->lp_ping_timestamp);
1019
1020         if (secs && !rtr->lp_ping_notsent &&
1021             cfs_time_after(now, cfs_time_add(rtr->lp_ping_timestamp,
1022                                              cfs_time_seconds(secs)))) {
1023                 int rc;
1024                 lnet_process_id_t id;
1025                 lnet_handle_md_t mdh;
1026
1027                 id.nid = rtr->lp_nid;
1028                 id.pid = LNET_PID_LUSTRE;
1029                 CDEBUG(D_NET, "Check: %s\n", libcfs_id2str(id));
1030
1031                 rtr->lp_ping_notsent   = 1;
1032                 rtr->lp_ping_timestamp = now;
1033
1034                 mdh = rcd->rcd_mdh;
1035
1036                 if (!rtr->lp_ping_deadline) {
1037                         rtr->lp_ping_deadline =
1038                                 cfs_time_shift(router_ping_timeout);
1039                 }
1040
1041                 lnet_net_unlock(rtr->lp_cpt);
1042
1043                 rc = LNetGet(LNET_NID_ANY, mdh, id, LNET_RESERVED_PORTAL,
1044                              LNET_PROTO_PING_MATCHBITS, 0);
1045
1046                 lnet_net_lock(rtr->lp_cpt);
1047                 if (rc)
1048                         rtr->lp_ping_notsent = 0; /* no event pending */
1049         }
1050
1051         lnet_peer_decref_locked(rtr);
1052 }
1053
1054 int
1055 lnet_router_checker_start(void)
1056 {
1057         struct task_struct *task;
1058         int rc;
1059         int eqsz = 0;
1060
1061         LASSERT(the_lnet.ln_rc_state == LNET_RC_STATE_SHUTDOWN);
1062
1063         if (check_routers_before_use &&
1064             dead_router_check_interval <= 0) {
1065                 LCONSOLE_ERROR_MSG(0x10a, "'dead_router_check_interval' must be set if 'check_routers_before_use' is set\n");
1066                 return -EINVAL;
1067         }
1068
1069         init_completion(&the_lnet.ln_rc_signal);
1070
1071         rc = LNetEQAlloc(0, lnet_router_checker_event, &the_lnet.ln_rc_eqh);
1072         if (rc) {
1073                 CERROR("Can't allocate EQ(%d): %d\n", eqsz, rc);
1074                 return -ENOMEM;
1075         }
1076
1077         the_lnet.ln_rc_state = LNET_RC_STATE_RUNNING;
1078         task = kthread_run(lnet_router_checker, NULL, "router_checker");
1079         if (IS_ERR(task)) {
1080                 rc = PTR_ERR(task);
1081                 CERROR("Can't start router checker thread: %d\n", rc);
1082                 /* block until event callback signals exit */
1083                 wait_for_completion(&the_lnet.ln_rc_signal);
1084                 rc = LNetEQFree(the_lnet.ln_rc_eqh);
1085                 LASSERT(!rc);
1086                 the_lnet.ln_rc_state = LNET_RC_STATE_SHUTDOWN;
1087                 return -ENOMEM;
1088         }
1089
1090         if (check_routers_before_use) {
1091                 /*
1092                  * Note that a helpful side-effect of pinging all known routers
1093                  * at startup is that it makes them drop stale connections they
1094                  * may have to a previous instance of me.
1095                  */
1096                 lnet_wait_known_routerstate();
1097         }
1098
1099         return 0;
1100 }
1101
1102 void
1103 lnet_router_checker_stop(void)
1104 {
1105         int rc;
1106
1107         if (the_lnet.ln_rc_state == LNET_RC_STATE_SHUTDOWN)
1108                 return;
1109
1110         LASSERT(the_lnet.ln_rc_state == LNET_RC_STATE_RUNNING);
1111         the_lnet.ln_rc_state = LNET_RC_STATE_STOPPING;
1112         /* wakeup the RC thread if it's sleeping */
1113         wake_up(&the_lnet.ln_rc_waitq);
1114
1115         /* block until event callback signals exit */
1116         wait_for_completion(&the_lnet.ln_rc_signal);
1117         LASSERT(the_lnet.ln_rc_state == LNET_RC_STATE_SHUTDOWN);
1118
1119         rc = LNetEQFree(the_lnet.ln_rc_eqh);
1120         LASSERT(!rc);
1121 }
1122
1123 static void
1124 lnet_prune_rc_data(int wait_unlink)
1125 {
1126         lnet_rc_data_t *rcd;
1127         lnet_rc_data_t *tmp;
1128         lnet_peer_t *lp;
1129         struct list_head head;
1130         int i = 2;
1131
1132         if (likely(the_lnet.ln_rc_state == LNET_RC_STATE_RUNNING &&
1133                    list_empty(&the_lnet.ln_rcd_deathrow) &&
1134                    list_empty(&the_lnet.ln_rcd_zombie)))
1135                 return;
1136
1137         INIT_LIST_HEAD(&head);
1138
1139         lnet_net_lock(LNET_LOCK_EX);
1140
1141         if (the_lnet.ln_rc_state != LNET_RC_STATE_RUNNING) {
1142                 /* router checker is stopping, prune all */
1143                 list_for_each_entry(lp, &the_lnet.ln_routers,
1144                                     lp_rtr_list) {
1145                         if (!lp->lp_rcd)
1146                                 continue;
1147
1148                         LASSERT(list_empty(&lp->lp_rcd->rcd_list));
1149                         list_add(&lp->lp_rcd->rcd_list,
1150                                  &the_lnet.ln_rcd_deathrow);
1151                         lp->lp_rcd = NULL;
1152                 }
1153         }
1154
1155         /* unlink all RCDs on deathrow list */
1156         list_splice_init(&the_lnet.ln_rcd_deathrow, &head);
1157
1158         if (!list_empty(&head)) {
1159                 lnet_net_unlock(LNET_LOCK_EX);
1160
1161                 list_for_each_entry(rcd, &head, rcd_list)
1162                         LNetMDUnlink(rcd->rcd_mdh);
1163
1164                 lnet_net_lock(LNET_LOCK_EX);
1165         }
1166
1167         list_splice_init(&head, &the_lnet.ln_rcd_zombie);
1168
1169         /* release all zombie RCDs */
1170         while (!list_empty(&the_lnet.ln_rcd_zombie)) {
1171                 list_for_each_entry_safe(rcd, tmp, &the_lnet.ln_rcd_zombie,
1172                                          rcd_list) {
1173                         if (LNetHandleIsInvalid(rcd->rcd_mdh))
1174                                 list_move(&rcd->rcd_list, &head);
1175                 }
1176
1177                 wait_unlink = wait_unlink &&
1178                               !list_empty(&the_lnet.ln_rcd_zombie);
1179
1180                 lnet_net_unlock(LNET_LOCK_EX);
1181
1182                 while (!list_empty(&head)) {
1183                         rcd = list_entry(head.next,
1184                                          lnet_rc_data_t, rcd_list);
1185                         list_del_init(&rcd->rcd_list);
1186                         lnet_destroy_rc_data(rcd);
1187                 }
1188
1189                 if (!wait_unlink)
1190                         return;
1191
1192                 i++;
1193                 CDEBUG(((i & (-i)) == i) ? D_WARNING : D_NET,
1194                        "Waiting for rc buffers to unlink\n");
1195                 set_current_state(TASK_UNINTERRUPTIBLE);
1196                 schedule_timeout(cfs_time_seconds(1) / 4);
1197
1198                 lnet_net_lock(LNET_LOCK_EX);
1199         }
1200
1201         lnet_net_unlock(LNET_LOCK_EX);
1202 }
1203
1204 /*
1205  * This function is called to check if the RC should block indefinitely.
1206  * It's called from lnet_router_checker() as well as being passed to
1207  * wait_event_interruptible() to avoid the lost wake_up problem.
1208  *
1209  * When it's called from wait_event_interruptible() it is necessary to
1210  * also not sleep if the rc state is not running to avoid a deadlock
1211  * when the system is shutting down
1212  */
1213 static inline bool
1214 lnet_router_checker_active(void)
1215 {
1216         if (the_lnet.ln_rc_state != LNET_RC_STATE_RUNNING)
1217                 return true;
1218
1219         /*
1220          * Router Checker thread needs to run when routing is enabled in
1221          * order to call lnet_update_ni_status_locked()
1222          */
1223         if (the_lnet.ln_routing)
1224                 return true;
1225
1226         return !list_empty(&the_lnet.ln_routers) &&
1227                 (live_router_check_interval > 0 ||
1228                  dead_router_check_interval > 0);
1229 }
1230
1231 static int
1232 lnet_router_checker(void *arg)
1233 {
1234         lnet_peer_t *rtr;
1235         struct list_head *entry;
1236
1237         cfs_block_allsigs();
1238
1239         while (the_lnet.ln_rc_state == LNET_RC_STATE_RUNNING) {
1240                 __u64 version;
1241                 int cpt;
1242                 int cpt2;
1243
1244                 cpt = lnet_net_lock_current();
1245 rescan:
1246                 version = the_lnet.ln_routers_version;
1247
1248                 list_for_each(entry, &the_lnet.ln_routers) {
1249                         rtr = list_entry(entry, lnet_peer_t, lp_rtr_list);
1250
1251                         cpt2 = lnet_cpt_of_nid_locked(rtr->lp_nid);
1252                         if (cpt != cpt2) {
1253                                 lnet_net_unlock(cpt);
1254                                 cpt = cpt2;
1255                                 lnet_net_lock(cpt);
1256                                 /* the routers list has changed */
1257                                 if (version != the_lnet.ln_routers_version)
1258                                         goto rescan;
1259                         }
1260
1261                         lnet_ping_router_locked(rtr);
1262
1263                         /* NB dropped lock */
1264                         if (version != the_lnet.ln_routers_version) {
1265                                 /* the routers list has changed */
1266                                 goto rescan;
1267                         }
1268                 }
1269
1270                 if (the_lnet.ln_routing)
1271                         lnet_update_ni_status_locked();
1272
1273                 lnet_net_unlock(cpt);
1274
1275                 lnet_prune_rc_data(0); /* don't wait for UNLINK */
1276
1277                 /*
1278                  * Call schedule_timeout() here always adds 1 to load average
1279                  * because kernel counts # active tasks as nr_running
1280                  * + nr_uninterruptible.
1281                  */
1282                 /*
1283                  * if there are any routes then wakeup every second.  If
1284                  * there are no routes then sleep indefinitely until woken
1285                  * up by a user adding a route
1286                  */
1287                 if (!lnet_router_checker_active())
1288                         wait_event_interruptible(the_lnet.ln_rc_waitq,
1289                                                  lnet_router_checker_active());
1290                 else
1291                         wait_event_interruptible_timeout(the_lnet.ln_rc_waitq,
1292                                                          false,
1293                                                          cfs_time_seconds(1));
1294         }
1295
1296         lnet_prune_rc_data(1); /* wait for UNLINK */
1297
1298         the_lnet.ln_rc_state = LNET_RC_STATE_SHUTDOWN;
1299         complete(&the_lnet.ln_rc_signal);
1300         /* The unlink event callback will signal final completion */
1301         return 0;
1302 }
1303
1304 void
1305 lnet_destroy_rtrbuf(lnet_rtrbuf_t *rb, int npages)
1306 {
1307         int sz = offsetof(lnet_rtrbuf_t, rb_kiov[npages]);
1308
1309         while (--npages >= 0)
1310                 __free_page(rb->rb_kiov[npages].bv_page);
1311
1312         LIBCFS_FREE(rb, sz);
1313 }
1314
1315 static lnet_rtrbuf_t *
1316 lnet_new_rtrbuf(lnet_rtrbufpool_t *rbp, int cpt)
1317 {
1318         int npages = rbp->rbp_npages;
1319         int sz = offsetof(lnet_rtrbuf_t, rb_kiov[npages]);
1320         struct page *page;
1321         lnet_rtrbuf_t *rb;
1322         int i;
1323
1324         LIBCFS_CPT_ALLOC(rb, lnet_cpt_table(), cpt, sz);
1325         if (!rb)
1326                 return NULL;
1327
1328         rb->rb_pool = rbp;
1329
1330         for (i = 0; i < npages; i++) {
1331                 page = alloc_pages_node(
1332                                 cfs_cpt_spread_node(lnet_cpt_table(), cpt),
1333                                 GFP_KERNEL | __GFP_ZERO, 0);
1334                 if (!page) {
1335                         while (--i >= 0)
1336                                 __free_page(rb->rb_kiov[i].bv_page);
1337
1338                         LIBCFS_FREE(rb, sz);
1339                         return NULL;
1340                 }
1341
1342                 rb->rb_kiov[i].bv_len = PAGE_SIZE;
1343                 rb->rb_kiov[i].bv_offset = 0;
1344                 rb->rb_kiov[i].bv_page = page;
1345         }
1346
1347         return rb;
1348 }
1349
1350 static void
1351 lnet_rtrpool_free_bufs(lnet_rtrbufpool_t *rbp, int cpt)
1352 {
1353         int npages = rbp->rbp_npages;
1354         struct list_head tmp;
1355         lnet_rtrbuf_t *rb;
1356         lnet_rtrbuf_t *temp;
1357
1358         if (!rbp->rbp_nbuffers) /* not initialized or already freed */
1359                 return;
1360
1361         INIT_LIST_HEAD(&tmp);
1362
1363         lnet_net_lock(cpt);
1364         lnet_drop_routed_msgs_locked(&rbp->rbp_msgs, cpt);
1365         list_splice_init(&rbp->rbp_bufs, &tmp);
1366         rbp->rbp_req_nbuffers = 0;
1367         rbp->rbp_nbuffers = 0;
1368         rbp->rbp_credits = 0;
1369         rbp->rbp_mincredits = 0;
1370         lnet_net_unlock(cpt);
1371
1372         /* Free buffers on the free list. */
1373         list_for_each_entry_safe(rb, temp, &tmp, rb_list) {
1374                 list_del(&rb->rb_list);
1375                 lnet_destroy_rtrbuf(rb, npages);
1376         }
1377 }
1378
1379 static int
1380 lnet_rtrpool_adjust_bufs(lnet_rtrbufpool_t *rbp, int nbufs, int cpt)
1381 {
1382         struct list_head rb_list;
1383         lnet_rtrbuf_t *rb;
1384         int num_rb;
1385         int num_buffers = 0;
1386         int old_req_nbufs;
1387         int npages = rbp->rbp_npages;
1388
1389         lnet_net_lock(cpt);
1390         /*
1391          * If we are called for less buffers than already in the pool, we
1392          * just lower the req_nbuffers number and excess buffers will be
1393          * thrown away as they are returned to the free list.  Credits
1394          * then get adjusted as well.
1395          * If we already have enough buffers allocated to serve the
1396          * increase requested, then we can treat that the same way as we
1397          * do the decrease.
1398          */
1399         num_rb = nbufs - rbp->rbp_nbuffers;
1400         if (nbufs <= rbp->rbp_req_nbuffers || num_rb <= 0) {
1401                 rbp->rbp_req_nbuffers = nbufs;
1402                 lnet_net_unlock(cpt);
1403                 return 0;
1404         }
1405         /*
1406          * store the older value of rbp_req_nbuffers and then set it to
1407          * the new request to prevent lnet_return_rx_credits_locked() from
1408          * freeing buffers that we need to keep around
1409          */
1410         old_req_nbufs = rbp->rbp_req_nbuffers;
1411         rbp->rbp_req_nbuffers = nbufs;
1412         lnet_net_unlock(cpt);
1413
1414         INIT_LIST_HEAD(&rb_list);
1415
1416         /*
1417          * allocate the buffers on a local list first.  If all buffers are
1418          * allocated successfully then join this list to the rbp buffer
1419          * list. If not then free all allocated buffers.
1420          */
1421         while (num_rb-- > 0) {
1422                 rb = lnet_new_rtrbuf(rbp, cpt);
1423                 if (!rb) {
1424                         CERROR("Failed to allocate %d route bufs of %d pages\n",
1425                                nbufs, npages);
1426
1427                         lnet_net_lock(cpt);
1428                         rbp->rbp_req_nbuffers = old_req_nbufs;
1429                         lnet_net_unlock(cpt);
1430
1431                         goto failed;
1432                 }
1433
1434                 list_add(&rb->rb_list, &rb_list);
1435                 num_buffers++;
1436         }
1437
1438         lnet_net_lock(cpt);
1439
1440         list_splice_tail(&rb_list, &rbp->rbp_bufs);
1441         rbp->rbp_nbuffers += num_buffers;
1442         rbp->rbp_credits += num_buffers;
1443         rbp->rbp_mincredits = rbp->rbp_credits;
1444         /*
1445          * We need to schedule blocked msg using the newly
1446          * added buffers.
1447          */
1448         while (!list_empty(&rbp->rbp_bufs) &&
1449                !list_empty(&rbp->rbp_msgs))
1450                 lnet_schedule_blocked_locked(rbp);
1451
1452         lnet_net_unlock(cpt);
1453
1454         return 0;
1455
1456 failed:
1457         while (!list_empty(&rb_list)) {
1458                 rb = list_entry(rb_list.next, lnet_rtrbuf_t, rb_list);
1459                 list_del(&rb->rb_list);
1460                 lnet_destroy_rtrbuf(rb, npages);
1461         }
1462
1463         return -ENOMEM;
1464 }
1465
1466 static void
1467 lnet_rtrpool_init(lnet_rtrbufpool_t *rbp, int npages)
1468 {
1469         INIT_LIST_HEAD(&rbp->rbp_msgs);
1470         INIT_LIST_HEAD(&rbp->rbp_bufs);
1471
1472         rbp->rbp_npages = npages;
1473         rbp->rbp_credits = 0;
1474         rbp->rbp_mincredits = 0;
1475 }
1476
1477 void
1478 lnet_rtrpools_free(int keep_pools)
1479 {
1480         lnet_rtrbufpool_t *rtrp;
1481         int i;
1482
1483         if (!the_lnet.ln_rtrpools) /* uninitialized or freed */
1484                 return;
1485
1486         cfs_percpt_for_each(rtrp, i, the_lnet.ln_rtrpools) {
1487                 lnet_rtrpool_free_bufs(&rtrp[LNET_TINY_BUF_IDX], i);
1488                 lnet_rtrpool_free_bufs(&rtrp[LNET_SMALL_BUF_IDX], i);
1489                 lnet_rtrpool_free_bufs(&rtrp[LNET_LARGE_BUF_IDX], i);
1490         }
1491
1492         if (!keep_pools) {
1493                 cfs_percpt_free(the_lnet.ln_rtrpools);
1494                 the_lnet.ln_rtrpools = NULL;
1495         }
1496 }
1497
1498 static int
1499 lnet_nrb_tiny_calculate(void)
1500 {
1501         int nrbs = LNET_NRB_TINY;
1502
1503         if (tiny_router_buffers < 0) {
1504                 LCONSOLE_ERROR_MSG(0x10c,
1505                                    "tiny_router_buffers=%d invalid when routing enabled\n",
1506                                    tiny_router_buffers);
1507                 return -EINVAL;
1508         }
1509
1510         if (tiny_router_buffers > 0)
1511                 nrbs = tiny_router_buffers;
1512
1513         nrbs /= LNET_CPT_NUMBER;
1514         return max(nrbs, LNET_NRB_TINY_MIN);
1515 }
1516
1517 static int
1518 lnet_nrb_small_calculate(void)
1519 {
1520         int nrbs = LNET_NRB_SMALL;
1521
1522         if (small_router_buffers < 0) {
1523                 LCONSOLE_ERROR_MSG(0x10c,
1524                                    "small_router_buffers=%d invalid when routing enabled\n",
1525                                    small_router_buffers);
1526                 return -EINVAL;
1527         }
1528
1529         if (small_router_buffers > 0)
1530                 nrbs = small_router_buffers;
1531
1532         nrbs /= LNET_CPT_NUMBER;
1533         return max(nrbs, LNET_NRB_SMALL_MIN);
1534 }
1535
1536 static int
1537 lnet_nrb_large_calculate(void)
1538 {
1539         int nrbs = LNET_NRB_LARGE;
1540
1541         if (large_router_buffers < 0) {
1542                 LCONSOLE_ERROR_MSG(0x10c,
1543                                    "large_router_buffers=%d invalid when routing enabled\n",
1544                                    large_router_buffers);
1545                 return -EINVAL;
1546         }
1547
1548         if (large_router_buffers > 0)
1549                 nrbs = large_router_buffers;
1550
1551         nrbs /= LNET_CPT_NUMBER;
1552         return max(nrbs, LNET_NRB_LARGE_MIN);
1553 }
1554
1555 int
1556 lnet_rtrpools_alloc(int im_a_router)
1557 {
1558         lnet_rtrbufpool_t *rtrp;
1559         int nrb_tiny;
1560         int nrb_small;
1561         int nrb_large;
1562         int rc;
1563         int i;
1564
1565         if (!strcmp(forwarding, "")) {
1566                 /* not set either way */
1567                 if (!im_a_router)
1568                         return 0;
1569         } else if (!strcmp(forwarding, "disabled")) {
1570                 /* explicitly disabled */
1571                 return 0;
1572         } else if (!strcmp(forwarding, "enabled")) {
1573                 /* explicitly enabled */
1574         } else {
1575                 LCONSOLE_ERROR_MSG(0x10b, "'forwarding' not set to either 'enabled' or 'disabled'\n");
1576                 return -EINVAL;
1577         }
1578
1579         nrb_tiny = lnet_nrb_tiny_calculate();
1580         if (nrb_tiny < 0)
1581                 return -EINVAL;
1582
1583         nrb_small = lnet_nrb_small_calculate();
1584         if (nrb_small < 0)
1585                 return -EINVAL;
1586
1587         nrb_large = lnet_nrb_large_calculate();
1588         if (nrb_large < 0)
1589                 return -EINVAL;
1590
1591         the_lnet.ln_rtrpools = cfs_percpt_alloc(lnet_cpt_table(),
1592                                                 LNET_NRBPOOLS *
1593                                                 sizeof(lnet_rtrbufpool_t));
1594         if (!the_lnet.ln_rtrpools) {
1595                 LCONSOLE_ERROR_MSG(0x10c,
1596                                    "Failed to initialize router buffe pool\n");
1597                 return -ENOMEM;
1598         }
1599
1600         cfs_percpt_for_each(rtrp, i, the_lnet.ln_rtrpools) {
1601                 lnet_rtrpool_init(&rtrp[LNET_TINY_BUF_IDX], 0);
1602                 rc = lnet_rtrpool_adjust_bufs(&rtrp[LNET_TINY_BUF_IDX],
1603                                               nrb_tiny, i);
1604                 if (rc)
1605                         goto failed;
1606
1607                 lnet_rtrpool_init(&rtrp[LNET_SMALL_BUF_IDX],
1608                                   LNET_NRB_SMALL_PAGES);
1609                 rc = lnet_rtrpool_adjust_bufs(&rtrp[LNET_SMALL_BUF_IDX],
1610                                               nrb_small, i);
1611                 if (rc)
1612                         goto failed;
1613
1614                 lnet_rtrpool_init(&rtrp[LNET_LARGE_BUF_IDX],
1615                                   LNET_NRB_LARGE_PAGES);
1616                 rc = lnet_rtrpool_adjust_bufs(&rtrp[LNET_LARGE_BUF_IDX],
1617                                               nrb_large, i);
1618                 if (rc)
1619                         goto failed;
1620         }
1621
1622         lnet_net_lock(LNET_LOCK_EX);
1623         the_lnet.ln_routing = 1;
1624         lnet_net_unlock(LNET_LOCK_EX);
1625
1626         return 0;
1627
1628  failed:
1629         lnet_rtrpools_free(0);
1630         return rc;
1631 }
1632
1633 static int
1634 lnet_rtrpools_adjust_helper(int tiny, int small, int large)
1635 {
1636         int nrb = 0;
1637         int rc = 0;
1638         int i;
1639         lnet_rtrbufpool_t *rtrp;
1640
1641         /*
1642          * If the provided values for each buffer pool are different than the
1643          * configured values, we need to take action.
1644          */
1645         if (tiny >= 0) {
1646                 tiny_router_buffers = tiny;
1647                 nrb = lnet_nrb_tiny_calculate();
1648                 cfs_percpt_for_each(rtrp, i, the_lnet.ln_rtrpools) {
1649                         rc = lnet_rtrpool_adjust_bufs(&rtrp[LNET_TINY_BUF_IDX],
1650                                                       nrb, i);
1651                         if (rc)
1652                                 return rc;
1653                 }
1654         }
1655         if (small >= 0) {
1656                 small_router_buffers = small;
1657                 nrb = lnet_nrb_small_calculate();
1658                 cfs_percpt_for_each(rtrp, i, the_lnet.ln_rtrpools) {
1659                         rc = lnet_rtrpool_adjust_bufs(&rtrp[LNET_SMALL_BUF_IDX],
1660                                                       nrb, i);
1661                         if (rc)
1662                                 return rc;
1663                 }
1664         }
1665         if (large >= 0) {
1666                 large_router_buffers = large;
1667                 nrb = lnet_nrb_large_calculate();
1668                 cfs_percpt_for_each(rtrp, i, the_lnet.ln_rtrpools) {
1669                         rc = lnet_rtrpool_adjust_bufs(&rtrp[LNET_LARGE_BUF_IDX],
1670                                                       nrb, i);
1671                         if (rc)
1672                                 return rc;
1673                 }
1674         }
1675
1676         return 0;
1677 }
1678
1679 int
1680 lnet_rtrpools_adjust(int tiny, int small, int large)
1681 {
1682         /*
1683          * this function doesn't revert the changes if adding new buffers
1684          * failed.  It's up to the user space caller to revert the
1685          * changes.
1686          */
1687         if (!the_lnet.ln_routing)
1688                 return 0;
1689
1690         return lnet_rtrpools_adjust_helper(tiny, small, large);
1691 }
1692
1693 int
1694 lnet_rtrpools_enable(void)
1695 {
1696         int rc = 0;
1697
1698         if (the_lnet.ln_routing)
1699                 return 0;
1700
1701         if (!the_lnet.ln_rtrpools)
1702                 /*
1703                  * If routing is turned off, and we have never
1704                  * initialized the pools before, just call the
1705                  * standard buffer pool allocation routine as
1706                  * if we are just configuring this for the first
1707                  * time.
1708                  */
1709                 rc = lnet_rtrpools_alloc(1);
1710         else
1711                 rc = lnet_rtrpools_adjust_helper(0, 0, 0);
1712         if (rc)
1713                 return rc;
1714
1715         lnet_net_lock(LNET_LOCK_EX);
1716         the_lnet.ln_routing = 1;
1717
1718         the_lnet.ln_ping_info->pi_features &= ~LNET_PING_FEAT_RTE_DISABLED;
1719         lnet_net_unlock(LNET_LOCK_EX);
1720
1721         return rc;
1722 }
1723
1724 void
1725 lnet_rtrpools_disable(void)
1726 {
1727         if (!the_lnet.ln_routing)
1728                 return;
1729
1730         lnet_net_lock(LNET_LOCK_EX);
1731         the_lnet.ln_routing = 0;
1732         the_lnet.ln_ping_info->pi_features |= LNET_PING_FEAT_RTE_DISABLED;
1733
1734         tiny_router_buffers = 0;
1735         small_router_buffers = 0;
1736         large_router_buffers = 0;
1737         lnet_net_unlock(LNET_LOCK_EX);
1738         lnet_rtrpools_free(1);
1739 }
1740
1741 int
1742 lnet_notify(lnet_ni_t *ni, lnet_nid_t nid, int alive, unsigned long when)
1743 {
1744         struct lnet_peer *lp = NULL;
1745         unsigned long now = cfs_time_current();
1746         int cpt = lnet_cpt_of_nid(nid);
1747
1748         LASSERT(!in_interrupt());
1749
1750         CDEBUG(D_NET, "%s notifying %s: %s\n",
1751                !ni ? "userspace" : libcfs_nid2str(ni->ni_nid),
1752                libcfs_nid2str(nid),
1753                alive ? "up" : "down");
1754
1755         if (ni &&
1756             LNET_NIDNET(ni->ni_nid) != LNET_NIDNET(nid)) {
1757                 CWARN("Ignoring notification of %s %s by %s (different net)\n",
1758                       libcfs_nid2str(nid), alive ? "birth" : "death",
1759                       libcfs_nid2str(ni->ni_nid));
1760                 return -EINVAL;
1761         }
1762
1763         /* can't do predictions... */
1764         if (cfs_time_after(when, now)) {
1765                 CWARN("Ignoring prediction from %s of %s %s %ld seconds in the future\n",
1766                       !ni ? "userspace" : libcfs_nid2str(ni->ni_nid),
1767                       libcfs_nid2str(nid), alive ? "up" : "down",
1768                       cfs_duration_sec(cfs_time_sub(when, now)));
1769                 return -EINVAL;
1770         }
1771
1772         if (ni && !alive &&          /* LND telling me she's down */
1773             !auto_down) {                      /* auto-down disabled */
1774                 CDEBUG(D_NET, "Auto-down disabled\n");
1775                 return 0;
1776         }
1777
1778         lnet_net_lock(cpt);
1779
1780         if (the_lnet.ln_shutdown) {
1781                 lnet_net_unlock(cpt);
1782                 return -ESHUTDOWN;
1783         }
1784
1785         lp = lnet_find_peer_locked(the_lnet.ln_peer_tables[cpt], nid);
1786         if (!lp) {
1787                 /* nid not found */
1788                 lnet_net_unlock(cpt);
1789                 CDEBUG(D_NET, "%s not found\n", libcfs_nid2str(nid));
1790                 return 0;
1791         }
1792
1793         /*
1794          * We can't fully trust LND on reporting exact peer last_alive
1795          * if he notifies us about dead peer. For example ksocklnd can
1796          * call us with when == _time_when_the_node_was_booted_ if
1797          * no connections were successfully established
1798          */
1799         if (ni && !alive && when < lp->lp_last_alive)
1800                 when = lp->lp_last_alive;
1801
1802         lnet_notify_locked(lp, !ni, alive, when);
1803
1804         if (ni)
1805                 lnet_ni_notify_locked(ni, lp);
1806
1807         lnet_peer_decref_locked(lp);
1808
1809         lnet_net_unlock(cpt);
1810         return 0;
1811 }
1812 EXPORT_SYMBOL(lnet_notify);