drivers/staging/lustre/lnet/lnet/lib-move.c

   1 /*
   2  * GPL HEADER START
   3  *
   4  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
   5  *
   6  * This program is free software; you can redistribute it and/or modify
   7  * it under the terms of the GNU General Public License version 2 only,
   8  * as published by the Free Software Foundation.
   9  *
  10  * This program is distributed in the hope that it will be useful, but
  11  * WITHOUT ANY WARRANTY; without even the implied warranty of
  12  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  13  * General Public License version 2 for more details (a copy is included
  14  * in the LICENSE file that accompanied this code).
  15  *
  16  * You should have received a copy of the GNU General Public License
  17  * version 2 along with this program; If not, see
  18  * http://www.gnu.org/licenses/gpl-2.0.html
  19  *
  20  * GPL HEADER END
  21  */
  22 /*
  23  * Copyright (c) 2003, 2010, Oracle and/or its affiliates. All rights reserved.
  24  * Use is subject to license terms.
  25  *
  26  * Copyright (c) 2011, 2015, Intel Corporation.
  27  */
  28 /*
  29  * This file is part of Lustre, http://www.lustre.org/
  30  * Lustre is a trademark of Sun Microsystems, Inc.
  31  *
  32  * lnet/lnet/lib-move.c
  33  *
  34  * Data movement routines
  35  */
  36
  37 #define DEBUG_SUBSYSTEM S_LNET
  38
  39 #include "../../include/linux/lnet/lib-lnet.h"
  40 #include <linux/nsproxy.h>
  41 #include <net/net_namespace.h>
  42
  43 static int local_nid_dist_zero = 1;
  44 module_param(local_nid_dist_zero, int, 0444);
  45 MODULE_PARM_DESC(local_nid_dist_zero, "Reserved");
  46
  47 int
  48 lnet_fail_nid(lnet_nid_t nid, unsigned int threshold)
  49 {
  50         lnet_test_peer_t *tp;
  51         lnet_test_peer_t *temp;
  52         struct list_head *el;
  53         struct list_head *next;
  54         struct list_head cull;
  55
  56         /* NB: use lnet_net_lock(0) to serialize operations on test peers */
  57         if (threshold) {
  58                 /* Adding a new entry */
  59                 LIBCFS_ALLOC(tp, sizeof(*tp));
  60                 if (!tp)
  61                         return -ENOMEM;
  62
  63                 tp->tp_nid = nid;
  64                 tp->tp_threshold = threshold;
  65
  66                 lnet_net_lock(0);
  67                 list_add_tail(&tp->tp_list, &the_lnet.ln_test_peers);
  68                 lnet_net_unlock(0);
  69                 return 0;
  70         }
  71
  72         /* removing entries */
  73         INIT_LIST_HEAD(&cull);
  74
  75         lnet_net_lock(0);
  76
  77         list_for_each_safe(el, next, &the_lnet.ln_test_peers) {
  78                 tp = list_entry(el, lnet_test_peer_t, tp_list);
  79
  80                 if (!tp->tp_threshold ||    /* needs culling anyway */
  81                     nid == LNET_NID_ANY ||       /* removing all entries */
  82                     tp->tp_nid == nid) {          /* matched this one */
  83                         list_del(&tp->tp_list);
  84                         list_add(&tp->tp_list, &cull);
  85                 }
  86         }
  87
  88         lnet_net_unlock(0);
  89
  90         list_for_each_entry_safe(tp, temp, &cull, tp_list) {
  91                 list_del(&tp->tp_list);
  92                 LIBCFS_FREE(tp, sizeof(*tp));
  93         }
  94         return 0;
  95 }
  96
  97 static int
  98 fail_peer(lnet_nid_t nid, int outgoing)
  99 {
 100         lnet_test_peer_t *tp;
 101         lnet_test_peer_t *temp;
 102         struct list_head *el;
 103         struct list_head *next;
 104         struct list_head cull;
 105         int fail = 0;
 106
 107         INIT_LIST_HEAD(&cull);
 108
 109         /* NB: use lnet_net_lock(0) to serialize operations on test peers */
 110         lnet_net_lock(0);
 111
 112         list_for_each_safe(el, next, &the_lnet.ln_test_peers) {
 113                 tp = list_entry(el, lnet_test_peer_t, tp_list);
 114
 115                 if (!tp->tp_threshold) {
 116                         /* zombie entry */
 117                         if (outgoing) {
 118                                 /*
 119                                  * only cull zombies on outgoing tests,
 120                                  * since we may be at interrupt priority on
 121                                  * incoming messages.
 122                                  */
 123                                 list_del(&tp->tp_list);
 124                                 list_add(&tp->tp_list, &cull);
 125                         }
 126                         continue;
 127                 }
 128
 129                 if (tp->tp_nid == LNET_NID_ANY || /* fail every peer */
 130                     nid == tp->tp_nid) {        /* fail this peer */
 131                         fail = 1;
 132
 133                         if (tp->tp_threshold != LNET_MD_THRESH_INF) {
 134                                 tp->tp_threshold--;
 135                                 if (outgoing &&
 136                                     !tp->tp_threshold) {
 137                                         /* see above */
 138                                         list_del(&tp->tp_list);
 139                                         list_add(&tp->tp_list, &cull);
 140                                 }
 141                         }
 142                         break;
 143                 }
 144         }
 145
 146         lnet_net_unlock(0);
 147
 148         list_for_each_entry_safe(tp, temp, &cull, tp_list) {
 149                 list_del(&tp->tp_list);
 150
 151                 LIBCFS_FREE(tp, sizeof(*tp));
 152         }
 153
 154         return fail;
 155 }
 156
 157 unsigned int
 158 lnet_iov_nob(unsigned int niov, struct kvec *iov)
 159 {
 160         unsigned int nob = 0;
 161
 162         LASSERT(!niov || iov);
 163         while (niov-- > 0)
 164                 nob += (iov++)->iov_len;
 165
 166         return nob;
 167 }
 168 EXPORT_SYMBOL(lnet_iov_nob);
 169
 170 void
 171 lnet_copy_iov2iter(struct iov_iter *to,
 172                    unsigned int nsiov, const struct kvec *siov,
 173                    unsigned int soffset, unsigned int nob)
 174 {
 175         /* NB diov, siov are READ-ONLY */
 176         const char *s;
 177         size_t left;
 178
 179         if (!nob)
 180                 return;
 181
 182         /* skip complete frags before 'soffset' */
 183         LASSERT(nsiov > 0);
 184         while (soffset >= siov->iov_len) {
 185                 soffset -= siov->iov_len;
 186                 siov++;
 187                 nsiov--;
 188                 LASSERT(nsiov > 0);
 189         }
 190
 191         s = (char *)siov->iov_base + soffset;
 192         left = siov->iov_len - soffset;
 193         do {
 194                 size_t n, copy = left;
 195                 LASSERT(nsiov > 0);
 196
 197                 if (copy > nob)
 198                         copy = nob;
 199                 n = copy_to_iter(s, copy, to);
 200                 if (n != copy)
 201                         return;
 202                 nob -= n;
 203
 204                 siov++;
 205                 s = (char *)siov->iov_base;
 206                 left = siov->iov_len;
 207                 nsiov--;
 208         } while (nob > 0);
 209 }
 210 EXPORT_SYMBOL(lnet_copy_iov2iter);
 211
 212 void
 213 lnet_copy_kiov2iter(struct iov_iter *to,
 214                     unsigned int nsiov, const lnet_kiov_t *siov,
 215                     unsigned int soffset, unsigned int nob)
 216 {
 217         if (!nob)
 218                 return;
 219
 220         LASSERT(!in_interrupt());
 221
 222         LASSERT(nsiov > 0);
 223         while (soffset >= siov->bv_len) {
 224                 soffset -= siov->bv_len;
 225                 siov++;
 226                 nsiov--;
 227                 LASSERT(nsiov > 0);
 228         }
 229
 230         do {
 231                 size_t copy = siov->bv_len - soffset, n;
 232
 233                 LASSERT(nsiov > 0);
 234
 235                 if (copy > nob)
 236                         copy = nob;
 237                 n = copy_page_to_iter(siov->bv_page,
 238                                       siov->bv_offset + soffset,
 239                                       copy, to);
 240                 if (n != copy)
 241                         return;
 242                 nob -= n;
 243                 siov++;
 244                 nsiov--;
 245                 soffset = 0;
 246         } while (nob > 0);
 247 }
 248 EXPORT_SYMBOL(lnet_copy_kiov2iter);
 249
 250 int
 251 lnet_extract_iov(int dst_niov, struct kvec *dst,
 252                  int src_niov, const struct kvec *src,
 253                  unsigned int offset, unsigned int len)
 254 {
 255         /*
 256          * Initialise 'dst' to the subset of 'src' starting at 'offset',
 257          * for exactly 'len' bytes, and return the number of entries.
 258          * NB not destructive to 'src'
 259          */
 260         unsigned int frag_len;
 261         unsigned int niov;
 262
 263         if (!len)                          /* no data => */
 264                 return 0;                    /* no frags */
 265
 266         LASSERT(src_niov > 0);
 267         while (offset >= src->iov_len) {      /* skip initial frags */
 268                 offset -= src->iov_len;
 269                 src_niov--;
 270                 src++;
 271                 LASSERT(src_niov > 0);
 272         }
 273
 274         niov = 1;
 275         for (;;) {
 276                 LASSERT(src_niov > 0);
 277                 LASSERT((int)niov <= dst_niov);
 278
 279                 frag_len = src->iov_len - offset;
 280                 dst->iov_base = ((char *)src->iov_base) + offset;
 281
 282                 if (len <= frag_len) {
 283                         dst->iov_len = len;
 284                         return niov;
 285                 }
 286
 287                 dst->iov_len = frag_len;
 288
 289                 len -= frag_len;
 290                 dst++;
 291                 src++;
 292                 niov++;
 293                 src_niov--;
 294                 offset = 0;
 295         }
 296 }
 297 EXPORT_SYMBOL(lnet_extract_iov);
 298
 299 unsigned int
 300 lnet_kiov_nob(unsigned int niov, lnet_kiov_t *kiov)
 301 {
 302         unsigned int nob = 0;
 303
 304         LASSERT(!niov || kiov);
 305         while (niov-- > 0)
 306                 nob += (kiov++)->bv_len;
 307
 308         return nob;
 309 }
 310 EXPORT_SYMBOL(lnet_kiov_nob);
 311
 312 int
 313 lnet_extract_kiov(int dst_niov, lnet_kiov_t *dst,
 314                   int src_niov, const lnet_kiov_t *src,
 315                   unsigned int offset, unsigned int len)
 316 {
 317         /*
 318          * Initialise 'dst' to the subset of 'src' starting at 'offset',
 319          * for exactly 'len' bytes, and return the number of entries.
 320          * NB not destructive to 'src'
 321          */
 322         unsigned int frag_len;
 323         unsigned int niov;
 324
 325         if (!len)                          /* no data => */
 326                 return 0;                    /* no frags */
 327
 328         LASSERT(src_niov > 0);
 329         while (offset >= src->bv_len) {      /* skip initial frags */
 330                 offset -= src->bv_len;
 331                 src_niov--;
 332                 src++;
 333                 LASSERT(src_niov > 0);
 334         }
 335
 336         niov = 1;
 337         for (;;) {
 338                 LASSERT(src_niov > 0);
 339                 LASSERT((int)niov <= dst_niov);
 340
 341                 frag_len = src->bv_len - offset;
 342                 dst->bv_page = src->bv_page;
 343                 dst->bv_offset = src->bv_offset + offset;
 344
 345                 if (len <= frag_len) {
 346                         dst->bv_len = len;
 347                         LASSERT(dst->bv_offset + dst->bv_len
 348                                         <= PAGE_SIZE);
 349                         return niov;
 350                 }
 351
 352                 dst->bv_len = frag_len;
 353                 LASSERT(dst->bv_offset + dst->bv_len <= PAGE_SIZE);
 354
 355                 len -= frag_len;
 356                 dst++;
 357                 src++;
 358                 niov++;
 359                 src_niov--;
 360                 offset = 0;
 361         }
 362 }
 363 EXPORT_SYMBOL(lnet_extract_kiov);
 364
 365 void
 366 lnet_ni_recv(lnet_ni_t *ni, void *private, lnet_msg_t *msg, int delayed,
 367              unsigned int offset, unsigned int mlen, unsigned int rlen)
 368 {
 369         unsigned int niov = 0;
 370         struct kvec *iov = NULL;
 371         lnet_kiov_t *kiov = NULL;
 372         struct iov_iter to;
 373         int rc;
 374
 375         LASSERT(!in_interrupt());
 376         LASSERT(!mlen || msg);
 377
 378         if (msg) {
 379                 LASSERT(msg->msg_receiving);
 380                 LASSERT(!msg->msg_sending);
 381                 LASSERT(rlen == msg->msg_len);
 382                 LASSERT(mlen <= msg->msg_len);
 383                 LASSERT(msg->msg_offset == offset);
 384                 LASSERT(msg->msg_wanted == mlen);
 385
 386                 msg->msg_receiving = 0;
 387
 388                 if (mlen) {
 389                         niov = msg->msg_niov;
 390                         iov  = msg->msg_iov;
 391                         kiov = msg->msg_kiov;
 392
 393                         LASSERT(niov > 0);
 394                         LASSERT(!iov != !kiov);
 395                 }
 396         }
 397
 398         if (iov) {
 399                 iov_iter_kvec(&to, ITER_KVEC | READ, iov, niov, mlen + offset);
 400                 iov_iter_advance(&to, offset);
 401         } else {
 402                 iov_iter_bvec(&to, ITER_BVEC | READ, kiov, niov, mlen + offset);
 403                 iov_iter_advance(&to, offset);
 404         }
 405         rc = ni->ni_lnd->lnd_recv(ni, private, msg, delayed, &to, rlen);
 406         if (rc < 0)
 407                 lnet_finalize(ni, msg, rc);
 408 }
 409
 410 static void
 411 lnet_setpayloadbuffer(lnet_msg_t *msg)
 412 {
 413         lnet_libmd_t *md = msg->msg_md;
 414
 415         LASSERT(msg->msg_len > 0);
 416         LASSERT(!msg->msg_routing);
 417         LASSERT(md);
 418         LASSERT(!msg->msg_niov);
 419         LASSERT(!msg->msg_iov);
 420         LASSERT(!msg->msg_kiov);
 421
 422         msg->msg_niov = md->md_niov;
 423         if (md->md_options & LNET_MD_KIOV)
 424                 msg->msg_kiov = md->md_iov.kiov;
 425         else
 426                 msg->msg_iov = md->md_iov.iov;
 427 }
 428
 429 void
 430 lnet_prep_send(lnet_msg_t *msg, int type, lnet_process_id_t target,
 431                unsigned int offset, unsigned int len)
 432 {
 433         msg->msg_type = type;
 434         msg->msg_target = target;
 435         msg->msg_len = len;
 436         msg->msg_offset = offset;
 437
 438         if (len)
 439                 lnet_setpayloadbuffer(msg);
 440
 441         memset(&msg->msg_hdr, 0, sizeof(msg->msg_hdr));
 442         msg->msg_hdr.type          = cpu_to_le32(type);
 443         msg->msg_hdr.dest_nid       = cpu_to_le64(target.nid);
 444         msg->msg_hdr.dest_pid       = cpu_to_le32(target.pid);
 445         /* src_nid will be set later */
 446         msg->msg_hdr.src_pid    = cpu_to_le32(the_lnet.ln_pid);
 447         msg->msg_hdr.payload_length = cpu_to_le32(len);
 448 }
 449
 450 static void
 451 lnet_ni_send(lnet_ni_t *ni, lnet_msg_t *msg)
 452 {
 453         void *priv = msg->msg_private;
 454         int rc;
 455
 456         LASSERT(!in_interrupt());
 457         LASSERT(LNET_NETTYP(LNET_NIDNET(ni->ni_nid)) == LOLND ||
 458                 (msg->msg_txcredit && msg->msg_peertxcredit));
 459
 460         rc = ni->ni_lnd->lnd_send(ni, priv, msg);
 461         if (rc < 0)
 462                 lnet_finalize(ni, msg, rc);
 463 }
 464
 465 static int
 466 lnet_ni_eager_recv(lnet_ni_t *ni, lnet_msg_t *msg)
 467 {
 468         int rc;
 469
 470         LASSERT(!msg->msg_sending);
 471         LASSERT(msg->msg_receiving);
 472         LASSERT(!msg->msg_rx_ready_delay);
 473         LASSERT(ni->ni_lnd->lnd_eager_recv);
 474
 475         msg->msg_rx_ready_delay = 1;
 476         rc = ni->ni_lnd->lnd_eager_recv(ni, msg->msg_private, msg,
 477                                         &msg->msg_private);
 478         if (rc) {
 479                 CERROR("recv from %s / send to %s aborted: eager_recv failed %d\n",
 480                        libcfs_nid2str(msg->msg_rxpeer->lp_nid),
 481                        libcfs_id2str(msg->msg_target), rc);
 482                 LASSERT(rc < 0); /* required by my callers */
 483         }
 484
 485         return rc;
 486 }
 487
 488 /* NB: caller shall hold a ref on 'lp' as I'd drop lnet_net_lock */
 489 static void
 490 lnet_ni_query_locked(lnet_ni_t *ni, lnet_peer_t *lp)
 491 {
 492         unsigned long last_alive = 0;
 493
 494         LASSERT(lnet_peer_aliveness_enabled(lp));
 495         LASSERT(ni->ni_lnd->lnd_query);
 496
 497         lnet_net_unlock(lp->lp_cpt);
 498         ni->ni_lnd->lnd_query(ni, lp->lp_nid, &last_alive);
 499         lnet_net_lock(lp->lp_cpt);
 500
 501         lp->lp_last_query = cfs_time_current();
 502
 503         if (last_alive) /* NI has updated timestamp */
 504                 lp->lp_last_alive = last_alive;
 505 }
 506
 507 /* NB: always called with lnet_net_lock held */
 508 static inline int
 509 lnet_peer_is_alive(lnet_peer_t *lp, unsigned long now)
 510 {
 511         int alive;
 512         unsigned long deadline;
 513
 514         LASSERT(lnet_peer_aliveness_enabled(lp));
 515
 516         /* Trust lnet_notify() if it has more recent aliveness news, but
 517          * ignore the initial assumed death (see lnet_peers_start_down()).
 518          */
 519         if (!lp->lp_alive && lp->lp_alive_count > 0 &&
 520             cfs_time_aftereq(lp->lp_timestamp, lp->lp_last_alive))
 521                 return 0;
 522
 523         deadline = cfs_time_add(lp->lp_last_alive,
 524                                 cfs_time_seconds(lp->lp_ni->ni_peertimeout));
 525         alive = cfs_time_after(deadline, now);
 526
 527         /* Update obsolete lp_alive except for routers assumed to be dead
 528          * initially, because router checker would update aliveness in this
 529          * case, and moreover lp_last_alive at peer creation is assumed.
 530          */
 531         if (alive && !lp->lp_alive &&
 532             !(lnet_isrouter(lp) && !lp->lp_alive_count))
 533                 lnet_notify_locked(lp, 0, 1, lp->lp_last_alive);
 534
 535         return alive;
 536 }
 537
 538 /*
 539  * NB: returns 1 when alive, 0 when dead, negative when error;
 540  *     may drop the lnet_net_lock
 541  */
 542 static int
 543 lnet_peer_alive_locked(lnet_peer_t *lp)
 544 {
 545         unsigned long now = cfs_time_current();
 546
 547         if (!lnet_peer_aliveness_enabled(lp))
 548                 return -ENODEV;
 549
 550         if (lnet_peer_is_alive(lp, now))
 551                 return 1;
 552
 553         /*
 554          * Peer appears dead, but we should avoid frequent NI queries (at
 555          * most once per lnet_queryinterval seconds).
 556          */
 557         if (lp->lp_last_query) {
 558                 static const int lnet_queryinterval = 1;
 559
 560                 unsigned long next_query =
 561                            cfs_time_add(lp->lp_last_query,
 562                                         cfs_time_seconds(lnet_queryinterval));
 563
 564                 if (time_before(now, next_query)) {
 565                         if (lp->lp_alive)
 566                                 CWARN("Unexpected aliveness of peer %s: %d < %d (%d/%d)\n",
 567                                       libcfs_nid2str(lp->lp_nid),
 568                                       (int)now, (int)next_query,
 569                                       lnet_queryinterval,
 570                                       lp->lp_ni->ni_peertimeout);
 571                         return 0;
 572                 }
 573         }
 574
 575         /* query NI for latest aliveness news */
 576         lnet_ni_query_locked(lp->lp_ni, lp);
 577
 578         if (lnet_peer_is_alive(lp, now))
 579                 return 1;
 580
 581         lnet_notify_locked(lp, 0, 0, lp->lp_last_alive);
 582         return 0;
 583 }
 584
 585 /**
 586  * \param msg The message to be sent.
 587  * \param do_send True if lnet_ni_send() should be called in this function.
 588  *        lnet_send() is going to lnet_net_unlock immediately after this, so
 589  *        it sets do_send FALSE and I don't do the unlock/send/lock bit.
 590  *
 591  * \retval LNET_CREDIT_OK If \a msg sent or OK to send.
 592  * \retval LNET_CREDIT_WAIT If \a msg blocked for credit.
 593  * \retval -EHOSTUNREACH If the next hop of the message appears dead.
 594  * \retval -ECANCELED If the MD of the message has been unlinked.
 595  */
 596 static int
 597 lnet_post_send_locked(lnet_msg_t *msg, int do_send)
 598 {
 599         lnet_peer_t *lp = msg->msg_txpeer;
 600         lnet_ni_t *ni = lp->lp_ni;
 601         int cpt = msg->msg_tx_cpt;
 602         struct lnet_tx_queue *tq = ni->ni_tx_queues[cpt];
 603
 604         /* non-lnet_send() callers have checked before */
 605         LASSERT(!do_send || msg->msg_tx_delayed);
 606         LASSERT(!msg->msg_receiving);
 607         LASSERT(msg->msg_tx_committed);
 608
 609         /* NB 'lp' is always the next hop */
 610         if (!(msg->msg_target.pid & LNET_PID_USERFLAG) &&
 611             !lnet_peer_alive_locked(lp)) {
 612                 the_lnet.ln_counters[cpt]->drop_count++;
 613                 the_lnet.ln_counters[cpt]->drop_length += msg->msg_len;
 614                 lnet_net_unlock(cpt);
 615
 616                 CNETERR("Dropping message for %s: peer not alive\n",
 617                         libcfs_id2str(msg->msg_target));
 618                 if (do_send)
 619                         lnet_finalize(ni, msg, -EHOSTUNREACH);
 620
 621                 lnet_net_lock(cpt);
 622                 return -EHOSTUNREACH;
 623         }
 624
 625         if (msg->msg_md &&
 626             (msg->msg_md->md_flags & LNET_MD_FLAG_ABORTED)) {
 627                 lnet_net_unlock(cpt);
 628
 629                 CNETERR("Aborting message for %s: LNetM[DE]Unlink() already called on the MD/ME.\n",
 630                         libcfs_id2str(msg->msg_target));
 631                 if (do_send)
 632                         lnet_finalize(ni, msg, -ECANCELED);
 633
 634                 lnet_net_lock(cpt);
 635                 return -ECANCELED;
 636         }
 637
 638         if (!msg->msg_peertxcredit) {
 639                 LASSERT((lp->lp_txcredits < 0) ==
 640                         !list_empty(&lp->lp_txq));
 641
 642                 msg->msg_peertxcredit = 1;
 643                 lp->lp_txqnob += msg->msg_len + sizeof(lnet_hdr_t);
 644                 lp->lp_txcredits--;
 645
 646                 if (lp->lp_txcredits < lp->lp_mintxcredits)
 647                         lp->lp_mintxcredits = lp->lp_txcredits;
 648
 649                 if (lp->lp_txcredits < 0) {
 650                         msg->msg_tx_delayed = 1;
 651                         list_add_tail(&msg->msg_list, &lp->lp_txq);
 652                         return LNET_CREDIT_WAIT;
 653                 }
 654         }
 655
 656         if (!msg->msg_txcredit) {
 657                 LASSERT((tq->tq_credits < 0) ==
 658                         !list_empty(&tq->tq_delayed));
 659
 660                 msg->msg_txcredit = 1;
 661                 tq->tq_credits--;
 662
 663                 if (tq->tq_credits < tq->tq_credits_min)
 664                         tq->tq_credits_min = tq->tq_credits;
 665
 666                 if (tq->tq_credits < 0) {
 667                         msg->msg_tx_delayed = 1;
 668                         list_add_tail(&msg->msg_list, &tq->tq_delayed);
 669                         return LNET_CREDIT_WAIT;
 670                 }
 671         }
 672
 673         if (do_send) {
 674                 lnet_net_unlock(cpt);
 675                 lnet_ni_send(ni, msg);
 676                 lnet_net_lock(cpt);
 677         }
 678         return LNET_CREDIT_OK;
 679 }
 680
 681 static lnet_rtrbufpool_t *
 682 lnet_msg2bufpool(lnet_msg_t *msg)
 683 {
 684         lnet_rtrbufpool_t *rbp;
 685         int cpt;
 686
 687         LASSERT(msg->msg_rx_committed);
 688
 689         cpt = msg->msg_rx_cpt;
 690         rbp = &the_lnet.ln_rtrpools[cpt][0];
 691
 692         LASSERT(msg->msg_len <= LNET_MTU);
 693         while (msg->msg_len > (unsigned int)rbp->rbp_npages * PAGE_SIZE) {
 694                 rbp++;
 695                 LASSERT(rbp < &the_lnet.ln_rtrpools[cpt][LNET_NRBPOOLS]);
 696         }
 697
 698         return rbp;
 699 }
 700
 701 static int
 702 lnet_post_routed_recv_locked(lnet_msg_t *msg, int do_recv)
 703 {
 704         /*
 705          * lnet_parse is going to lnet_net_unlock immediately after this, so it
 706          * sets do_recv FALSE and I don't do the unlock/send/lock bit.
 707          * I return LNET_CREDIT_WAIT if msg blocked and LNET_CREDIT_OK if
 708          * received or OK to receive
 709          */
 710         lnet_peer_t *lp = msg->msg_rxpeer;
 711         lnet_rtrbufpool_t *rbp;
 712         lnet_rtrbuf_t *rb;
 713
 714         LASSERT(!msg->msg_iov);
 715         LASSERT(!msg->msg_kiov);
 716         LASSERT(!msg->msg_niov);
 717         LASSERT(msg->msg_routing);
 718         LASSERT(msg->msg_receiving);
 719         LASSERT(!msg->msg_sending);
 720
 721         /* non-lnet_parse callers only receive delayed messages */
 722         LASSERT(!do_recv || msg->msg_rx_delayed);
 723
 724         if (!msg->msg_peerrtrcredit) {
 725                 LASSERT((lp->lp_rtrcredits < 0) ==
 726                         !list_empty(&lp->lp_rtrq));
 727
 728                 msg->msg_peerrtrcredit = 1;
 729                 lp->lp_rtrcredits--;
 730                 if (lp->lp_rtrcredits < lp->lp_minrtrcredits)
 731                         lp->lp_minrtrcredits = lp->lp_rtrcredits;
 732
 733                 if (lp->lp_rtrcredits < 0) {
 734                         /* must have checked eager_recv before here */
 735                         LASSERT(msg->msg_rx_ready_delay);
 736                         msg->msg_rx_delayed = 1;
 737                         list_add_tail(&msg->msg_list, &lp->lp_rtrq);
 738                         return LNET_CREDIT_WAIT;
 739                 }
 740         }
 741
 742         rbp = lnet_msg2bufpool(msg);
 743
 744         if (!msg->msg_rtrcredit) {
 745                 msg->msg_rtrcredit = 1;
 746                 rbp->rbp_credits--;
 747                 if (rbp->rbp_credits < rbp->rbp_mincredits)
 748                         rbp->rbp_mincredits = rbp->rbp_credits;
 749
 750                 if (rbp->rbp_credits < 0) {
 751                         /* must have checked eager_recv before here */
 752                         LASSERT(msg->msg_rx_ready_delay);
 753                         msg->msg_rx_delayed = 1;
 754                         list_add_tail(&msg->msg_list, &rbp->rbp_msgs);
 755                         return LNET_CREDIT_WAIT;
 756                 }
 757         }
 758
 759         LASSERT(!list_empty(&rbp->rbp_bufs));
 760         rb = list_entry(rbp->rbp_bufs.next, lnet_rtrbuf_t, rb_list);
 761         list_del(&rb->rb_list);
 762
 763         msg->msg_niov = rbp->rbp_npages;
 764         msg->msg_kiov = &rb->rb_kiov[0];
 765
 766         if (do_recv) {
 767                 int cpt = msg->msg_rx_cpt;
 768
 769                 lnet_net_unlock(cpt);
 770                 lnet_ni_recv(lp->lp_ni, msg->msg_private, msg, 1,
 771                              0, msg->msg_len, msg->msg_len);
 772                 lnet_net_lock(cpt);
 773         }
 774         return LNET_CREDIT_OK;
 775 }
 776
 777 void
 778 lnet_return_tx_credits_locked(lnet_msg_t *msg)
 779 {
 780         lnet_peer_t *txpeer = msg->msg_txpeer;
 781         lnet_msg_t *msg2;
 782
 783         if (msg->msg_txcredit) {
 784                 struct lnet_ni *ni = txpeer->lp_ni;
 785                 struct lnet_tx_queue *tq = ni->ni_tx_queues[msg->msg_tx_cpt];
 786
 787                 /* give back NI txcredits */
 788                 msg->msg_txcredit = 0;
 789
 790                 LASSERT((tq->tq_credits < 0) ==
 791                         !list_empty(&tq->tq_delayed));
 792
 793                 tq->tq_credits++;
 794                 if (tq->tq_credits <= 0) {
 795                         msg2 = list_entry(tq->tq_delayed.next,
 796                                           lnet_msg_t, msg_list);
 797                         list_del(&msg2->msg_list);
 798
 799                         LASSERT(msg2->msg_txpeer->lp_ni == ni);
 800                         LASSERT(msg2->msg_tx_delayed);
 801
 802                         (void)lnet_post_send_locked(msg2, 1);
 803                 }
 804         }
 805
 806         if (msg->msg_peertxcredit) {
 807                 /* give back peer txcredits */
 808                 msg->msg_peertxcredit = 0;
 809
 810                 LASSERT((txpeer->lp_txcredits < 0) ==
 811                         !list_empty(&txpeer->lp_txq));
 812
 813                 txpeer->lp_txqnob -= msg->msg_len + sizeof(lnet_hdr_t);
 814                 LASSERT(txpeer->lp_txqnob >= 0);
 815
 816                 txpeer->lp_txcredits++;
 817                 if (txpeer->lp_txcredits <= 0) {
 818                         msg2 = list_entry(txpeer->lp_txq.next,
 819                                           lnet_msg_t, msg_list);
 820                         list_del(&msg2->msg_list);
 821
 822                         LASSERT(msg2->msg_txpeer == txpeer);
 823                         LASSERT(msg2->msg_tx_delayed);
 824
 825                         (void)lnet_post_send_locked(msg2, 1);
 826                 }
 827         }
 828
 829         if (txpeer) {
 830                 msg->msg_txpeer = NULL;
 831                 lnet_peer_decref_locked(txpeer);
 832         }
 833 }
 834
 835 void
 836 lnet_schedule_blocked_locked(lnet_rtrbufpool_t *rbp)
 837 {
 838         lnet_msg_t *msg;
 839
 840         if (list_empty(&rbp->rbp_msgs))
 841                 return;
 842         msg = list_entry(rbp->rbp_msgs.next,
 843                          lnet_msg_t, msg_list);
 844         list_del(&msg->msg_list);
 845
 846         (void)lnet_post_routed_recv_locked(msg, 1);
 847 }
 848
 849 void
 850 lnet_drop_routed_msgs_locked(struct list_head *list, int cpt)
 851 {
 852         struct list_head drop;
 853         lnet_msg_t *msg;
 854         lnet_msg_t *tmp;
 855
 856         INIT_LIST_HEAD(&drop);
 857
 858         list_splice_init(list, &drop);
 859
 860         lnet_net_unlock(cpt);
 861
 862         list_for_each_entry_safe(msg, tmp, &drop, msg_list) {
 863                 lnet_ni_recv(msg->msg_rxpeer->lp_ni, msg->msg_private, NULL,
 864                              0, 0, 0, msg->msg_hdr.payload_length);
 865                 list_del_init(&msg->msg_list);
 866                 lnet_finalize(NULL, msg, -ECANCELED);
 867         }
 868
 869         lnet_net_lock(cpt);
 870 }
 871
 872 void
 873 lnet_return_rx_credits_locked(lnet_msg_t *msg)
 874 {
 875         lnet_peer_t *rxpeer = msg->msg_rxpeer;
 876         lnet_msg_t *msg2;
 877
 878         if (msg->msg_rtrcredit) {
 879                 /* give back global router credits */
 880                 lnet_rtrbuf_t *rb;
 881                 lnet_rtrbufpool_t *rbp;
 882
 883                 /*
 884                  * NB If a msg ever blocks for a buffer in rbp_msgs, it stays
 885                  * there until it gets one allocated, or aborts the wait
 886                  * itself
 887                  */
 888                 LASSERT(msg->msg_kiov);
 889
 890                 rb = list_entry(msg->msg_kiov, lnet_rtrbuf_t, rb_kiov[0]);
 891                 rbp = rb->rb_pool;
 892
 893                 msg->msg_kiov = NULL;
 894                 msg->msg_rtrcredit = 0;
 895
 896                 LASSERT(rbp == lnet_msg2bufpool(msg));
 897
 898                 LASSERT((rbp->rbp_credits > 0) ==
 899                         !list_empty(&rbp->rbp_bufs));
 900
 901                 /*
 902                  * If routing is now turned off, we just drop this buffer and
 903                  * don't bother trying to return credits.
 904                  */
 905                 if (!the_lnet.ln_routing) {
 906                         lnet_destroy_rtrbuf(rb, rbp->rbp_npages);
 907                         goto routing_off;
 908                 }
 909
 910                 /*
 911                  * It is possible that a user has lowered the desired number of
 912                  * buffers in this pool.  Make sure we never put back
 913                  * more buffers than the stated number.
 914                  */
 915                 if (unlikely(rbp->rbp_credits >= rbp->rbp_req_nbuffers)) {
 916                         /* Discard this buffer so we don't have too many. */
 917                         lnet_destroy_rtrbuf(rb, rbp->rbp_npages);
 918                         rbp->rbp_nbuffers--;
 919                 } else {
 920                         list_add(&rb->rb_list, &rbp->rbp_bufs);
 921                         rbp->rbp_credits++;
 922                         if (rbp->rbp_credits <= 0)
 923                                 lnet_schedule_blocked_locked(rbp);
 924                 }
 925         }
 926
 927 routing_off:
 928         if (msg->msg_peerrtrcredit) {
 929                 /* give back peer router credits */
 930                 msg->msg_peerrtrcredit = 0;
 931
 932                 LASSERT((rxpeer->lp_rtrcredits < 0) ==
 933                         !list_empty(&rxpeer->lp_rtrq));
 934
 935                 rxpeer->lp_rtrcredits++;
 936                 /*
 937                  * drop all messages which are queued to be routed on that
 938                  * peer.
 939                  */
 940                 if (!the_lnet.ln_routing) {
 941                         lnet_drop_routed_msgs_locked(&rxpeer->lp_rtrq,
 942                                                      msg->msg_rx_cpt);
 943                 } else if (rxpeer->lp_rtrcredits <= 0) {
 944                         msg2 = list_entry(rxpeer->lp_rtrq.next,
 945                                           lnet_msg_t, msg_list);
 946                         list_del(&msg2->msg_list);
 947
 948                         (void)lnet_post_routed_recv_locked(msg2, 1);
 949                 }
 950         }
 951         if (rxpeer) {
 952                 msg->msg_rxpeer = NULL;
 953                 lnet_peer_decref_locked(rxpeer);
 954         }
 955 }
 956
 957 static int
 958 lnet_compare_routes(lnet_route_t *r1, lnet_route_t *r2)
 959 {
 960         lnet_peer_t *p1 = r1->lr_gateway;
 961         lnet_peer_t *p2 = r2->lr_gateway;
 962         int r1_hops = (r1->lr_hops == LNET_UNDEFINED_HOPS) ? 1 : r1->lr_hops;
 963         int r2_hops = (r2->lr_hops == LNET_UNDEFINED_HOPS) ? 1 : r2->lr_hops;
 964
 965         if (r1->lr_priority < r2->lr_priority)
 966                 return 1;
 967
 968         if (r1->lr_priority > r2->lr_priority)
 969                 return -ERANGE;
 970
 971         if (r1_hops < r2_hops)
 972                 return 1;
 973
 974         if (r1_hops > r2_hops)
 975                 return -ERANGE;
 976
 977         if (p1->lp_txqnob < p2->lp_txqnob)
 978                 return 1;
 979
 980         if (p1->lp_txqnob > p2->lp_txqnob)
 981                 return -ERANGE;
 982
 983         if (p1->lp_txcredits > p2->lp_txcredits)
 984                 return 1;
 985
 986         if (p1->lp_txcredits < p2->lp_txcredits)
 987                 return -ERANGE;
 988
 989         if (r1->lr_seq - r2->lr_seq <= 0)
 990                 return 1;
 991
 992         return -ERANGE;
 993 }
 994
 995 static lnet_peer_t *
 996 lnet_find_route_locked(lnet_ni_t *ni, lnet_nid_t target, lnet_nid_t rtr_nid)
 997 {
 998         lnet_remotenet_t *rnet;
 999         lnet_route_t *route;
1000         lnet_route_t *best_route;
1001         lnet_route_t *last_route;
1002         struct lnet_peer *lp_best;
1003         struct lnet_peer *lp;
1004         int rc;
1005
1006         /*
1007          * If @rtr_nid is not LNET_NID_ANY, return the gateway with
1008          * rtr_nid nid, otherwise find the best gateway I can use
1009          */
1010         rnet = lnet_find_net_locked(LNET_NIDNET(target));
1011         if (!rnet)
1012                 return NULL;
1013
1014         lp_best = NULL;
1015         best_route = NULL;
1016         last_route = NULL;
1017         list_for_each_entry(route, &rnet->lrn_routes, lr_list) {
1018                 lp = route->lr_gateway;
1019
1020                 if (!lnet_is_route_alive(route))
1021                         continue;
1022
1023                 if (ni && lp->lp_ni != ni)
1024                         continue;
1025
1026                 if (lp->lp_nid == rtr_nid) /* it's pre-determined router */
1027                         return lp;
1028
1029                 if (!lp_best) {
1030                         best_route = route;
1031                         last_route = route;
1032                         lp_best = lp;
1033                         continue;
1034                 }
1035
1036                 /* no protection on below fields, but it's harmless */
1037                 if (last_route->lr_seq - route->lr_seq < 0)
1038                         last_route = route;
1039
1040                 rc = lnet_compare_routes(route, best_route);
1041                 if (rc < 0)
1042                         continue;
1043
1044                 best_route = route;
1045                 lp_best = lp;
1046         }
1047
1048         /*
1049          * set sequence number on the best router to the latest sequence + 1
1050          * so we can round-robin all routers, it's race and inaccurate but
1051          * harmless and functional
1052          */
1053         if (best_route)
1054                 best_route->lr_seq = last_route->lr_seq + 1;
1055         return lp_best;
1056 }
1057
1058 int
1059 lnet_send(lnet_nid_t src_nid, lnet_msg_t *msg, lnet_nid_t rtr_nid)
1060 {
1061         lnet_nid_t dst_nid = msg->msg_target.nid;
1062         struct lnet_ni *src_ni;
1063         struct lnet_ni *local_ni;
1064         struct lnet_peer *lp;
1065         int cpt;
1066         int cpt2;
1067         int rc;
1068
1069         /*
1070          * NB: rtr_nid is set to LNET_NID_ANY for all current use-cases,
1071          * but we might want to use pre-determined router for ACK/REPLY
1072          * in the future
1073          */
1074         /* NB: ni == interface pre-determined (ACK/REPLY) */
1075         LASSERT(!msg->msg_txpeer);
1076         LASSERT(!msg->msg_sending);
1077         LASSERT(!msg->msg_target_is_router);
1078         LASSERT(!msg->msg_receiving);
1079
1080         msg->msg_sending = 1;
1081
1082         LASSERT(!msg->msg_tx_committed);
1083         cpt = lnet_cpt_of_nid(rtr_nid == LNET_NID_ANY ? dst_nid : rtr_nid);
1084  again:
1085         lnet_net_lock(cpt);
1086
1087         if (the_lnet.ln_shutdown) {
1088                 lnet_net_unlock(cpt);
1089                 return -ESHUTDOWN;
1090         }
1091
1092         if (src_nid == LNET_NID_ANY) {
1093                 src_ni = NULL;
1094         } else {
1095                 src_ni = lnet_nid2ni_locked(src_nid, cpt);
1096                 if (!src_ni) {
1097                         lnet_net_unlock(cpt);
1098                         LCONSOLE_WARN("Can't send to %s: src %s is not a local nid\n",
1099                                       libcfs_nid2str(dst_nid),
1100                                       libcfs_nid2str(src_nid));
1101                         return -EINVAL;
1102                 }
1103                 LASSERT(!msg->msg_routing);
1104         }
1105
1106         /* Is this for someone on a local network? */
1107         local_ni = lnet_net2ni_locked(LNET_NIDNET(dst_nid), cpt);
1108
1109         if (local_ni) {
1110                 if (!src_ni) {
1111                         src_ni = local_ni;
1112                         src_nid = src_ni->ni_nid;
1113                 } else if (src_ni == local_ni) {
1114                         lnet_ni_decref_locked(local_ni, cpt);
1115                 } else {
1116                         lnet_ni_decref_locked(local_ni, cpt);
1117                         lnet_ni_decref_locked(src_ni, cpt);
1118                         lnet_net_unlock(cpt);
1119                         LCONSOLE_WARN("No route to %s via from %s\n",
1120                                       libcfs_nid2str(dst_nid),
1121                                       libcfs_nid2str(src_nid));
1122                         return -EINVAL;
1123                 }
1124
1125                 LASSERT(src_nid != LNET_NID_ANY);
1126                 lnet_msg_commit(msg, cpt);
1127
1128                 if (!msg->msg_routing)
1129                         msg->msg_hdr.src_nid = cpu_to_le64(src_nid);
1130
1131                 if (src_ni == the_lnet.ln_loni) {
1132                         /* No send credit hassles with LOLND */
1133                         lnet_net_unlock(cpt);
1134                         lnet_ni_send(src_ni, msg);
1135
1136                         lnet_net_lock(cpt);
1137                         lnet_ni_decref_locked(src_ni, cpt);
1138                         lnet_net_unlock(cpt);
1139                         return 0;
1140                 }
1141
1142                 rc = lnet_nid2peer_locked(&lp, dst_nid, cpt);
1143                 /* lp has ref on src_ni; lose mine */
1144                 lnet_ni_decref_locked(src_ni, cpt);
1145                 if (rc) {
1146                         lnet_net_unlock(cpt);
1147                         LCONSOLE_WARN("Error %d finding peer %s\n", rc,
1148                                       libcfs_nid2str(dst_nid));
1149                         /* ENOMEM or shutting down */
1150                         return rc;
1151                 }
1152                 LASSERT(lp->lp_ni == src_ni);
1153         } else {
1154                 /* sending to a remote network */
1155                 lp = lnet_find_route_locked(src_ni, dst_nid, rtr_nid);
1156                 if (!lp) {
1157                         if (src_ni)
1158                                 lnet_ni_decref_locked(src_ni, cpt);
1159                         lnet_net_unlock(cpt);
1160
1161                         LCONSOLE_WARN("No route to %s via %s (all routers down)\n",
1162                                       libcfs_id2str(msg->msg_target),
1163                                       libcfs_nid2str(src_nid));
1164                         return -EHOSTUNREACH;
1165                 }
1166
1167                 /*
1168                  * rtr_nid is LNET_NID_ANY or NID of pre-determined router,
1169                  * it's possible that rtr_nid isn't LNET_NID_ANY and lp isn't
1170                  * pre-determined router, this can happen if router table
1171                  * was changed when we release the lock
1172                  */
1173                 if (rtr_nid != lp->lp_nid) {
1174                         cpt2 = lnet_cpt_of_nid_locked(lp->lp_nid);
1175                         if (cpt2 != cpt) {
1176                                 if (src_ni)
1177                                         lnet_ni_decref_locked(src_ni, cpt);
1178                                 lnet_net_unlock(cpt);
1179
1180                                 rtr_nid = lp->lp_nid;
1181                                 cpt = cpt2;
1182                                 goto again;
1183                         }
1184                 }
1185
1186                 CDEBUG(D_NET, "Best route to %s via %s for %s %d\n",
1187                        libcfs_nid2str(dst_nid), libcfs_nid2str(lp->lp_nid),
1188                        lnet_msgtyp2str(msg->msg_type), msg->msg_len);
1189
1190                 if (!src_ni) {
1191                         src_ni = lp->lp_ni;
1192                         src_nid = src_ni->ni_nid;
1193                 } else {
1194                         LASSERT(src_ni == lp->lp_ni);
1195                         lnet_ni_decref_locked(src_ni, cpt);
1196                 }
1197
1198                 lnet_peer_addref_locked(lp);
1199
1200                 LASSERT(src_nid != LNET_NID_ANY);
1201                 lnet_msg_commit(msg, cpt);
1202
1203                 if (!msg->msg_routing) {
1204                         /* I'm the source and now I know which NI to send on */
1205                         msg->msg_hdr.src_nid = cpu_to_le64(src_nid);
1206                 }
1207
1208                 msg->msg_target_is_router = 1;
1209                 msg->msg_target.nid = lp->lp_nid;
1210                 msg->msg_target.pid = LNET_PID_LUSTRE;
1211         }
1212
1213         /* 'lp' is our best choice of peer */
1214
1215         LASSERT(!msg->msg_peertxcredit);
1216         LASSERT(!msg->msg_txcredit);
1217         LASSERT(!msg->msg_txpeer);
1218
1219         msg->msg_txpeer = lp;              /* msg takes my ref on lp */
1220
1221         rc = lnet_post_send_locked(msg, 0);
1222         lnet_net_unlock(cpt);
1223
1224         if (rc < 0)
1225                 return rc;
1226
1227         if (rc == LNET_CREDIT_OK)
1228                 lnet_ni_send(src_ni, msg);
1229
1230         return 0; /* rc == LNET_CREDIT_OK or LNET_CREDIT_WAIT */
1231 }
1232
1233 void
1234 lnet_drop_message(lnet_ni_t *ni, int cpt, void *private, unsigned int nob)
1235 {
1236         lnet_net_lock(cpt);
1237         the_lnet.ln_counters[cpt]->drop_count++;
1238         the_lnet.ln_counters[cpt]->drop_length += nob;
1239         lnet_net_unlock(cpt);
1240
1241         lnet_ni_recv(ni, private, NULL, 0, 0, 0, nob);
1242 }
1243
1244 static void
1245 lnet_recv_put(lnet_ni_t *ni, lnet_msg_t *msg)
1246 {
1247         lnet_hdr_t *hdr = &msg->msg_hdr;
1248
1249         if (msg->msg_wanted)
1250                 lnet_setpayloadbuffer(msg);
1251
1252         lnet_build_msg_event(msg, LNET_EVENT_PUT);
1253
1254         /*
1255          * Must I ACK?  If so I'll grab the ack_wmd out of the header and put
1256          * it back into the ACK during lnet_finalize()
1257          */
1258         msg->msg_ack = !lnet_is_wire_handle_none(&hdr->msg.put.ack_wmd) &&
1259                        !(msg->msg_md->md_options & LNET_MD_ACK_DISABLE);
1260
1261         lnet_ni_recv(ni, msg->msg_private, msg, msg->msg_rx_delayed,
1262                      msg->msg_offset, msg->msg_wanted, hdr->payload_length);
1263 }
1264
1265 static int
1266 lnet_parse_put(lnet_ni_t *ni, lnet_msg_t *msg)
1267 {
1268         lnet_hdr_t *hdr = &msg->msg_hdr;
1269         struct lnet_match_info info;
1270         bool ready_delay;
1271         int rc;
1272
1273         /* Convert put fields to host byte order */
1274         hdr->msg.put.match_bits = le64_to_cpu(hdr->msg.put.match_bits);
1275         hdr->msg.put.ptl_index  = le32_to_cpu(hdr->msg.put.ptl_index);
1276         hdr->msg.put.offset     = le32_to_cpu(hdr->msg.put.offset);
1277
1278         info.mi_id.nid  = hdr->src_nid;
1279         info.mi_id.pid  = hdr->src_pid;
1280         info.mi_opc     = LNET_MD_OP_PUT;
1281         info.mi_portal  = hdr->msg.put.ptl_index;
1282         info.mi_rlength = hdr->payload_length;
1283         info.mi_roffset = hdr->msg.put.offset;
1284         info.mi_mbits   = hdr->msg.put.match_bits;
1285
1286         msg->msg_rx_ready_delay = !ni->ni_lnd->lnd_eager_recv;
1287         ready_delay = msg->msg_rx_ready_delay;
1288
1289  again:
1290         rc = lnet_ptl_match_md(&info, msg);
1291         switch (rc) {
1292         default:
1293                 LBUG();
1294
1295         case LNET_MATCHMD_OK:
1296                 lnet_recv_put(ni, msg);
1297                 return 0;
1298
1299         case LNET_MATCHMD_NONE:
1300                 /**
1301                  * no eager_recv or has already called it, should
1302                  * have been attached on delayed list
1303                  */
1304                 if (ready_delay)
1305                         return 0;
1306
1307                 rc = lnet_ni_eager_recv(ni, msg);
1308                 if (!rc) {
1309                         ready_delay = true;
1310                         goto again;
1311                 }
1312                 /* fall through */
1313
1314         case LNET_MATCHMD_DROP:
1315                 CNETERR("Dropping PUT from %s portal %d match %llu offset %d length %d: %d\n",
1316                         libcfs_id2str(info.mi_id), info.mi_portal,
1317                         info.mi_mbits, info.mi_roffset, info.mi_rlength, rc);
1318
1319                 return -ENOENT; /* -ve: OK but no match */
1320         }
1321 }
1322
1323 static int
1324 lnet_parse_get(lnet_ni_t *ni, lnet_msg_t *msg, int rdma_get)
1325 {
1326         struct lnet_match_info info;
1327         lnet_hdr_t *hdr = &msg->msg_hdr;
1328         lnet_handle_wire_t reply_wmd;
1329         int rc;
1330
1331         /* Convert get fields to host byte order */
1332         hdr->msg.get.match_bits  = le64_to_cpu(hdr->msg.get.match_bits);
1333         hdr->msg.get.ptl_index   = le32_to_cpu(hdr->msg.get.ptl_index);
1334         hdr->msg.get.sink_length = le32_to_cpu(hdr->msg.get.sink_length);
1335         hdr->msg.get.src_offset  = le32_to_cpu(hdr->msg.get.src_offset);
1336
1337         info.mi_id.nid  = hdr->src_nid;
1338         info.mi_id.pid  = hdr->src_pid;
1339         info.mi_opc     = LNET_MD_OP_GET;
1340         info.mi_portal  = hdr->msg.get.ptl_index;
1341         info.mi_rlength = hdr->msg.get.sink_length;
1342         info.mi_roffset = hdr->msg.get.src_offset;
1343         info.mi_mbits   = hdr->msg.get.match_bits;
1344
1345         rc = lnet_ptl_match_md(&info, msg);
1346         if (rc == LNET_MATCHMD_DROP) {
1347                 CNETERR("Dropping GET from %s portal %d match %llu offset %d length %d\n",
1348                         libcfs_id2str(info.mi_id), info.mi_portal,
1349                         info.mi_mbits, info.mi_roffset, info.mi_rlength);
1350                 return -ENOENT; /* -ve: OK but no match */
1351         }
1352
1353         LASSERT(rc == LNET_MATCHMD_OK);
1354
1355         lnet_build_msg_event(msg, LNET_EVENT_GET);
1356
1357         reply_wmd = hdr->msg.get.return_wmd;
1358
1359         lnet_prep_send(msg, LNET_MSG_REPLY, info.mi_id,
1360                        msg->msg_offset, msg->msg_wanted);
1361
1362         msg->msg_hdr.msg.reply.dst_wmd = reply_wmd;
1363
1364         if (rdma_get) {
1365                 /* The LND completes the REPLY from her recv procedure */
1366                 lnet_ni_recv(ni, msg->msg_private, msg, 0,
1367                              msg->msg_offset, msg->msg_len, msg->msg_len);
1368                 return 0;
1369         }
1370
1371         lnet_ni_recv(ni, msg->msg_private, NULL, 0, 0, 0, 0);
1372         msg->msg_receiving = 0;
1373
1374         rc = lnet_send(ni->ni_nid, msg, LNET_NID_ANY);
1375         if (rc < 0) {
1376                 /* didn't get as far as lnet_ni_send() */
1377                 CERROR("%s: Unable to send REPLY for GET from %s: %d\n",
1378                        libcfs_nid2str(ni->ni_nid),
1379                        libcfs_id2str(info.mi_id), rc);
1380
1381                 lnet_finalize(ni, msg, rc);
1382         }
1383
1384         return 0;
1385 }
1386
1387 static int
1388 lnet_parse_reply(lnet_ni_t *ni, lnet_msg_t *msg)
1389 {
1390         void *private = msg->msg_private;
1391         lnet_hdr_t *hdr = &msg->msg_hdr;
1392         lnet_process_id_t src = {0};
1393         lnet_libmd_t *md;
1394         int rlength;
1395         int mlength;
1396         int cpt;
1397
1398         cpt = lnet_cpt_of_cookie(hdr->msg.reply.dst_wmd.wh_object_cookie);
1399         lnet_res_lock(cpt);
1400
1401         src.nid = hdr->src_nid;
1402         src.pid = hdr->src_pid;
1403
1404         /* NB handles only looked up by creator (no flips) */
1405         md = lnet_wire_handle2md(&hdr->msg.reply.dst_wmd);
1406         if (!md || !md->md_threshold || md->md_me) {
1407                 CNETERR("%s: Dropping REPLY from %s for %s MD %#llx.%#llx\n",
1408                         libcfs_nid2str(ni->ni_nid), libcfs_id2str(src),
1409                         !md ? "invalid" : "inactive",
1410                         hdr->msg.reply.dst_wmd.wh_interface_cookie,
1411                         hdr->msg.reply.dst_wmd.wh_object_cookie);
1412                 if (md && md->md_me)
1413                         CERROR("REPLY MD also attached to portal %d\n",
1414                                md->md_me->me_portal);
1415
1416                 lnet_res_unlock(cpt);
1417                 return -ENOENT; /* -ve: OK but no match */
1418         }
1419
1420         LASSERT(!md->md_offset);
1421
1422         rlength = hdr->payload_length;
1423         mlength = min_t(uint, rlength, md->md_length);
1424
1425         if (mlength < rlength &&
1426             !(md->md_options & LNET_MD_TRUNCATE)) {
1427                 CNETERR("%s: Dropping REPLY from %s length %d for MD %#llx would overflow (%d)\n",
1428                         libcfs_nid2str(ni->ni_nid), libcfs_id2str(src),
1429                         rlength, hdr->msg.reply.dst_wmd.wh_object_cookie,
1430                         mlength);
1431                 lnet_res_unlock(cpt);
1432                 return -ENOENT; /* -ve: OK but no match */
1433         }
1434
1435         CDEBUG(D_NET, "%s: Reply from %s of length %d/%d into md %#llx\n",
1436                libcfs_nid2str(ni->ni_nid), libcfs_id2str(src),
1437                mlength, rlength, hdr->msg.reply.dst_wmd.wh_object_cookie);
1438
1439         lnet_msg_attach_md(msg, md, 0, mlength);
1440
1441         if (mlength)
1442                 lnet_setpayloadbuffer(msg);
1443
1444         lnet_res_unlock(cpt);
1445
1446         lnet_build_msg_event(msg, LNET_EVENT_REPLY);
1447
1448         lnet_ni_recv(ni, private, msg, 0, 0, mlength, rlength);
1449         return 0;
1450 }
1451
1452 static int
1453 lnet_parse_ack(lnet_ni_t *ni, lnet_msg_t *msg)
1454 {
1455         lnet_hdr_t *hdr = &msg->msg_hdr;
1456         lnet_process_id_t src = {0};
1457         lnet_libmd_t *md;
1458         int cpt;
1459
1460         src.nid = hdr->src_nid;
1461         src.pid = hdr->src_pid;
1462
1463         /* Convert ack fields to host byte order */
1464         hdr->msg.ack.match_bits = le64_to_cpu(hdr->msg.ack.match_bits);
1465         hdr->msg.ack.mlength = le32_to_cpu(hdr->msg.ack.mlength);
1466
1467         cpt = lnet_cpt_of_cookie(hdr->msg.ack.dst_wmd.wh_object_cookie);
1468         lnet_res_lock(cpt);
1469
1470         /* NB handles only looked up by creator (no flips) */
1471         md = lnet_wire_handle2md(&hdr->msg.ack.dst_wmd);
1472         if (!md || !md->md_threshold || md->md_me) {
1473                 /* Don't moan; this is expected */
1474                 CDEBUG(D_NET,
1475                        "%s: Dropping ACK from %s to %s MD %#llx.%#llx\n",
1476                        libcfs_nid2str(ni->ni_nid), libcfs_id2str(src),
1477                        !md ? "invalid" : "inactive",
1478                        hdr->msg.ack.dst_wmd.wh_interface_cookie,
1479                        hdr->msg.ack.dst_wmd.wh_object_cookie);
1480                 if (md && md->md_me)
1481                         CERROR("Source MD also attached to portal %d\n",
1482                                md->md_me->me_portal);
1483
1484                 lnet_res_unlock(cpt);
1485                 return -ENOENT; /* -ve! */
1486         }
1487
1488         CDEBUG(D_NET, "%s: ACK from %s into md %#llx\n",
1489                libcfs_nid2str(ni->ni_nid), libcfs_id2str(src),
1490                hdr->msg.ack.dst_wmd.wh_object_cookie);
1491
1492         lnet_msg_attach_md(msg, md, 0, 0);
1493
1494         lnet_res_unlock(cpt);
1495
1496         lnet_build_msg_event(msg, LNET_EVENT_ACK);
1497
1498         lnet_ni_recv(ni, msg->msg_private, msg, 0, 0, 0, msg->msg_len);
1499         return 0;
1500 }
1501
1502 /**
1503  * \retval LNET_CREDIT_OK       If \a msg is forwarded
1504  * \retval LNET_CREDIT_WAIT     If \a msg is blocked because w/o buffer
1505  * \retval -ve                  error code
1506  */
1507 int
1508 lnet_parse_forward_locked(lnet_ni_t *ni, lnet_msg_t *msg)
1509 {
1510         int rc = 0;
1511
1512         if (!the_lnet.ln_routing)
1513                 return -ECANCELED;
1514
1515         if (msg->msg_rxpeer->lp_rtrcredits <= 0 ||
1516             lnet_msg2bufpool(msg)->rbp_credits <= 0) {
1517                 if (!ni->ni_lnd->lnd_eager_recv) {
1518                         msg->msg_rx_ready_delay = 1;
1519                 } else {
1520                         lnet_net_unlock(msg->msg_rx_cpt);
1521                         rc = lnet_ni_eager_recv(ni, msg);
1522                         lnet_net_lock(msg->msg_rx_cpt);
1523                 }
1524         }
1525
1526         if (!rc)
1527                 rc = lnet_post_routed_recv_locked(msg, 0);
1528         return rc;
1529 }
1530
1531 int
1532 lnet_parse_local(lnet_ni_t *ni, lnet_msg_t *msg)
1533 {
1534         int rc;
1535
1536         switch (msg->msg_type) {
1537         case LNET_MSG_ACK:
1538                 rc = lnet_parse_ack(ni, msg);
1539                 break;
1540         case LNET_MSG_PUT:
1541                 rc = lnet_parse_put(ni, msg);
1542                 break;
1543         case LNET_MSG_GET:
1544                 rc = lnet_parse_get(ni, msg, msg->msg_rdma_get);
1545                 break;
1546         case LNET_MSG_REPLY:
1547                 rc = lnet_parse_reply(ni, msg);
1548                 break;
1549         default: /* prevent an unused label if !kernel */
1550                 LASSERT(0);
1551                 return -EPROTO;
1552         }
1553
1554         LASSERT(!rc || rc == -ENOENT);
1555         return rc;
1556 }
1557
1558 char *
1559 lnet_msgtyp2str(int type)
1560 {
1561         switch (type) {
1562         case LNET_MSG_ACK:
1563                 return "ACK";
1564         case LNET_MSG_PUT:
1565                 return "PUT";
1566         case LNET_MSG_GET:
1567                 return "GET";
1568         case LNET_MSG_REPLY:
1569                 return "REPLY";
1570         case LNET_MSG_HELLO:
1571                 return "HELLO";
1572         default:
1573                 return "<UNKNOWN>";
1574         }
1575 }
1576
1577 void
1578 lnet_print_hdr(lnet_hdr_t *hdr)
1579 {
1580         lnet_process_id_t src = {0};
1581         lnet_process_id_t dst = {0};
1582         char *type_str = lnet_msgtyp2str(hdr->type);
1583
1584         src.nid = hdr->src_nid;
1585         src.pid = hdr->src_pid;
1586
1587         dst.nid = hdr->dest_nid;
1588         dst.pid = hdr->dest_pid;
1589
1590         CWARN("P3 Header at %p of type %s\n", hdr, type_str);
1591         CWARN("    From %s\n", libcfs_id2str(src));
1592         CWARN("    To   %s\n", libcfs_id2str(dst));
1593
1594         switch (hdr->type) {
1595         default:
1596                 break;
1597
1598         case LNET_MSG_PUT:
1599                 CWARN("    Ptl index %d, ack md %#llx.%#llx, match bits %llu\n",
1600                       hdr->msg.put.ptl_index,
1601                       hdr->msg.put.ack_wmd.wh_interface_cookie,
1602                       hdr->msg.put.ack_wmd.wh_object_cookie,
1603                       hdr->msg.put.match_bits);
1604                 CWARN("    Length %d, offset %d, hdr data %#llx\n",
1605                       hdr->payload_length, hdr->msg.put.offset,
1606                       hdr->msg.put.hdr_data);
1607                 break;
1608
1609         case LNET_MSG_GET:
1610                 CWARN("    Ptl index %d, return md %#llx.%#llx, match bits %llu\n",
1611                       hdr->msg.get.ptl_index,
1612                       hdr->msg.get.return_wmd.wh_interface_cookie,
1613                       hdr->msg.get.return_wmd.wh_object_cookie,
1614                       hdr->msg.get.match_bits);
1615                 CWARN("    Length %d, src offset %d\n",
1616                       hdr->msg.get.sink_length,
1617                       hdr->msg.get.src_offset);
1618                 break;
1619
1620         case LNET_MSG_ACK:
1621                 CWARN("    dst md %#llx.%#llx, manipulated length %d\n",
1622                       hdr->msg.ack.dst_wmd.wh_interface_cookie,
1623                       hdr->msg.ack.dst_wmd.wh_object_cookie,
1624                       hdr->msg.ack.mlength);
1625                 break;
1626
1627         case LNET_MSG_REPLY:
1628                 CWARN("    dst md %#llx.%#llx, length %d\n",
1629                       hdr->msg.reply.dst_wmd.wh_interface_cookie,
1630                       hdr->msg.reply.dst_wmd.wh_object_cookie,
1631                       hdr->payload_length);
1632         }
1633 }
1634
1635 int
1636 lnet_parse(lnet_ni_t *ni, lnet_hdr_t *hdr, lnet_nid_t from_nid,
1637            void *private, int rdma_req)
1638 {
1639         int rc = 0;
1640         int cpt;
1641         int for_me;
1642         struct lnet_msg *msg;
1643         lnet_pid_t dest_pid;
1644         lnet_nid_t dest_nid;
1645         lnet_nid_t src_nid;
1646         __u32 payload_length;
1647         __u32 type;
1648
1649         LASSERT(!in_interrupt());
1650
1651         type = le32_to_cpu(hdr->type);
1652         src_nid = le64_to_cpu(hdr->src_nid);
1653         dest_nid = le64_to_cpu(hdr->dest_nid);
1654         dest_pid = le32_to_cpu(hdr->dest_pid);
1655         payload_length = le32_to_cpu(hdr->payload_length);
1656
1657         for_me = (ni->ni_nid == dest_nid);
1658         cpt = lnet_cpt_of_nid(from_nid);
1659
1660         switch (type) {
1661         case LNET_MSG_ACK:
1662         case LNET_MSG_GET:
1663                 if (payload_length > 0) {
1664                         CERROR("%s, src %s: bad %s payload %d (0 expected)\n",
1665                                libcfs_nid2str(from_nid),
1666                                libcfs_nid2str(src_nid),
1667                                lnet_msgtyp2str(type), payload_length);
1668                         return -EPROTO;
1669                 }
1670                 break;
1671
1672         case LNET_MSG_PUT:
1673         case LNET_MSG_REPLY:
1674                 if (payload_length >
1675                    (__u32)(for_me ? LNET_MAX_PAYLOAD : LNET_MTU)) {
1676                         CERROR("%s, src %s: bad %s payload %d (%d max expected)\n",
1677                                libcfs_nid2str(from_nid),
1678                                libcfs_nid2str(src_nid),
1679                                lnet_msgtyp2str(type),
1680                                payload_length,
1681                                for_me ? LNET_MAX_PAYLOAD : LNET_MTU);
1682                         return -EPROTO;
1683                 }
1684                 break;
1685
1686         default:
1687                 CERROR("%s, src %s: Bad message type 0x%x\n",
1688                        libcfs_nid2str(from_nid),
1689                        libcfs_nid2str(src_nid), type);
1690                 return -EPROTO;
1691         }
1692
1693         if (the_lnet.ln_routing &&
1694             ni->ni_last_alive != ktime_get_real_seconds()) {
1695                 /* NB: so far here is the only place to set NI status to "up */
1696                 lnet_ni_lock(ni);
1697                 ni->ni_last_alive = ktime_get_real_seconds();
1698                 if (ni->ni_status &&
1699                     ni->ni_status->ns_status == LNET_NI_STATUS_DOWN)
1700                         ni->ni_status->ns_status = LNET_NI_STATUS_UP;
1701                 lnet_ni_unlock(ni);
1702         }
1703
1704         /*
1705          * Regard a bad destination NID as a protocol error.  Senders should
1706          * know what they're doing; if they don't they're misconfigured, buggy
1707          * or malicious so we chop them off at the knees :)
1708          */
1709         if (!for_me) {
1710                 if (LNET_NIDNET(dest_nid) == LNET_NIDNET(ni->ni_nid)) {
1711                         /* should have gone direct */
1712                         CERROR("%s, src %s: Bad dest nid %s (should have been sent direct)\n",
1713                                libcfs_nid2str(from_nid),
1714                                libcfs_nid2str(src_nid),
1715                                libcfs_nid2str(dest_nid));
1716                         return -EPROTO;
1717                 }
1718
1719                 if (lnet_islocalnid(dest_nid)) {
1720                         /*
1721                          * dest is another local NI; sender should have used
1722                          * this node's NID on its own network
1723                          */
1724                         CERROR("%s, src %s: Bad dest nid %s (it's my nid but on a different network)\n",
1725                                libcfs_nid2str(from_nid),
1726                                libcfs_nid2str(src_nid),
1727                                libcfs_nid2str(dest_nid));
1728                         return -EPROTO;
1729                 }
1730
1731                 if (rdma_req && type == LNET_MSG_GET) {
1732                         CERROR("%s, src %s: Bad optimized GET for %s (final destination must be me)\n",
1733                                libcfs_nid2str(from_nid),
1734                                libcfs_nid2str(src_nid),
1735                                libcfs_nid2str(dest_nid));
1736                         return -EPROTO;
1737                 }
1738
1739                 if (!the_lnet.ln_routing) {
1740                         CERROR("%s, src %s: Dropping message for %s (routing not enabled)\n",
1741                                libcfs_nid2str(from_nid),
1742                                libcfs_nid2str(src_nid),
1743                                libcfs_nid2str(dest_nid));
1744                         goto drop;
1745                 }
1746         }
1747
1748         /*
1749          * Message looks OK; we're not going to return an error, so we MUST
1750          * call back lnd_recv() come what may...
1751          */
1752         if (!list_empty(&the_lnet.ln_test_peers) && /* normally we don't */
1753             fail_peer(src_nid, 0)) {         /* shall we now? */
1754                 CERROR("%s, src %s: Dropping %s to simulate failure\n",
1755                        libcfs_nid2str(from_nid), libcfs_nid2str(src_nid),
1756                        lnet_msgtyp2str(type));
1757                 goto drop;
1758         }
1759
1760         if (!list_empty(&the_lnet.ln_drop_rules) &&
1761             lnet_drop_rule_match(hdr)) {
1762                 CDEBUG(D_NET, "%s, src %s, dst %s: Dropping %s to simulate silent message loss\n",
1763                        libcfs_nid2str(from_nid), libcfs_nid2str(src_nid),
1764                        libcfs_nid2str(dest_nid), lnet_msgtyp2str(type));
1765                 goto drop;
1766         }
1767
1768         msg = lnet_msg_alloc();
1769         if (!msg) {
1770                 CERROR("%s, src %s: Dropping %s (out of memory)\n",
1771                        libcfs_nid2str(from_nid), libcfs_nid2str(src_nid),
1772                        lnet_msgtyp2str(type));
1773                 goto drop;
1774         }
1775
1776         /* msg zeroed in lnet_msg_alloc;
1777          * i.e. flags all clear, pointers NULL etc
1778          */
1779         msg->msg_type = type;
1780         msg->msg_private = private;
1781         msg->msg_receiving = 1;
1782         msg->msg_rdma_get = rdma_req;
1783         msg->msg_wanted = payload_length;
1784         msg->msg_len = payload_length;
1785         msg->msg_offset = 0;
1786         msg->msg_hdr = *hdr;
1787         /* for building message event */
1788         msg->msg_from = from_nid;
1789         if (!for_me) {
1790                 msg->msg_target.pid     = dest_pid;
1791                 msg->msg_target.nid     = dest_nid;
1792                 msg->msg_routing        = 1;
1793
1794         } else {
1795                 /* convert common msg->hdr fields to host byteorder */
1796                 msg->msg_hdr.type       = type;
1797                 msg->msg_hdr.src_nid    = src_nid;
1798                 msg->msg_hdr.src_pid    = le32_to_cpu(msg->msg_hdr.src_pid);
1799                 msg->msg_hdr.dest_nid   = dest_nid;
1800                 msg->msg_hdr.dest_pid   = dest_pid;
1801                 msg->msg_hdr.payload_length = payload_length;
1802         }
1803
1804         lnet_net_lock(cpt);
1805         rc = lnet_nid2peer_locked(&msg->msg_rxpeer, from_nid, cpt);
1806         if (rc) {
1807                 lnet_net_unlock(cpt);
1808                 CERROR("%s, src %s: Dropping %s (error %d looking up sender)\n",
1809                        libcfs_nid2str(from_nid), libcfs_nid2str(src_nid),
1810                        lnet_msgtyp2str(type), rc);
1811                 lnet_msg_free(msg);
1812                 if (rc == -ESHUTDOWN)
1813                         /* We are shutting down. Don't do anything more */
1814                         return 0;
1815                 goto drop;
1816         }
1817
1818         if (lnet_isrouter(msg->msg_rxpeer)) {
1819                 lnet_peer_set_alive(msg->msg_rxpeer);
1820                 if (avoid_asym_router_failure &&
1821                     LNET_NIDNET(src_nid) != LNET_NIDNET(from_nid)) {
1822                         /* received a remote message from router, update
1823                          * remote NI status on this router.
1824                          * NB: multi-hop routed message will be ignored.
1825                          */
1826                         lnet_router_ni_update_locked(msg->msg_rxpeer,
1827                                                      LNET_NIDNET(src_nid));
1828                 }
1829         }
1830
1831         lnet_msg_commit(msg, cpt);
1832
1833         /* message delay simulation */
1834         if (unlikely(!list_empty(&the_lnet.ln_delay_rules) &&
1835                      lnet_delay_rule_match_locked(hdr, msg))) {
1836                 lnet_net_unlock(cpt);
1837                 return 0;
1838         }
1839
1840         if (!for_me) {
1841                 rc = lnet_parse_forward_locked(ni, msg);
1842                 lnet_net_unlock(cpt);
1843
1844                 if (rc < 0)
1845                         goto free_drop;
1846
1847                 if (rc == LNET_CREDIT_OK) {
1848                         lnet_ni_recv(ni, msg->msg_private, msg, 0,
1849                                      0, payload_length, payload_length);
1850                 }
1851                 return 0;
1852         }
1853
1854         lnet_net_unlock(cpt);
1855
1856         rc = lnet_parse_local(ni, msg);
1857         if (rc)
1858                 goto free_drop;
1859         return 0;
1860
1861  free_drop:
1862         LASSERT(!msg->msg_md);
1863         lnet_finalize(ni, msg, rc);
1864
1865  drop:
1866         lnet_drop_message(ni, cpt, private, payload_length);
1867         return 0;
1868 }
1869 EXPORT_SYMBOL(lnet_parse);
1870
1871 void
1872 lnet_drop_delayed_msg_list(struct list_head *head, char *reason)
1873 {
1874         while (!list_empty(head)) {
1875                 lnet_process_id_t id = {0};
1876                 lnet_msg_t *msg;
1877
1878                 msg = list_entry(head->next, lnet_msg_t, msg_list);
1879                 list_del(&msg->msg_list);
1880
1881                 id.nid = msg->msg_hdr.src_nid;
1882                 id.pid = msg->msg_hdr.src_pid;
1883
1884                 LASSERT(!msg->msg_md);
1885                 LASSERT(msg->msg_rx_delayed);
1886                 LASSERT(msg->msg_rxpeer);
1887                 LASSERT(msg->msg_hdr.type == LNET_MSG_PUT);
1888
1889                 CWARN("Dropping delayed PUT from %s portal %d match %llu offset %d length %d: %s\n",
1890                       libcfs_id2str(id),
1891                       msg->msg_hdr.msg.put.ptl_index,
1892                       msg->msg_hdr.msg.put.match_bits,
1893                       msg->msg_hdr.msg.put.offset,
1894                       msg->msg_hdr.payload_length, reason);
1895
1896                 /*
1897                  * NB I can't drop msg's ref on msg_rxpeer until after I've
1898                  * called lnet_drop_message(), so I just hang onto msg as well
1899                  * until that's done
1900                  */
1901                 lnet_drop_message(msg->msg_rxpeer->lp_ni,
1902                                   msg->msg_rxpeer->lp_cpt,
1903                                   msg->msg_private, msg->msg_len);
1904                 /*
1905                  * NB: message will not generate event because w/o attached MD,
1906                  * but we still should give error code so lnet_msg_decommit()
1907                  * can skip counters operations and other checks.
1908                  */
1909                 lnet_finalize(msg->msg_rxpeer->lp_ni, msg, -ENOENT);
1910         }
1911 }
1912
1913 void
1914 lnet_recv_delayed_msg_list(struct list_head *head)
1915 {
1916         while (!list_empty(head)) {
1917                 lnet_msg_t *msg;
1918                 lnet_process_id_t id;
1919
1920                 msg = list_entry(head->next, lnet_msg_t, msg_list);
1921                 list_del(&msg->msg_list);
1922
1923                 /*
1924                  * md won't disappear under me, since each msg
1925                  * holds a ref on it
1926                  */
1927                 id.nid = msg->msg_hdr.src_nid;
1928                 id.pid = msg->msg_hdr.src_pid;
1929
1930                 LASSERT(msg->msg_rx_delayed);
1931                 LASSERT(msg->msg_md);
1932                 LASSERT(msg->msg_rxpeer);
1933                 LASSERT(msg->msg_hdr.type == LNET_MSG_PUT);
1934
1935                 CDEBUG(D_NET, "Resuming delayed PUT from %s portal %d match %llu offset %d length %d.\n",
1936                        libcfs_id2str(id), msg->msg_hdr.msg.put.ptl_index,
1937                        msg->msg_hdr.msg.put.match_bits,
1938                        msg->msg_hdr.msg.put.offset,
1939                        msg->msg_hdr.payload_length);
1940
1941                 lnet_recv_put(msg->msg_rxpeer->lp_ni, msg);
1942         }
1943 }
1944
1945 /**
1946  * Initiate an asynchronous PUT operation.
1947  *
1948  * There are several events associated with a PUT: completion of the send on
1949  * the initiator node (LNET_EVENT_SEND), and when the send completes
1950  * successfully, the receipt of an acknowledgment (LNET_EVENT_ACK) indicating
1951  * that the operation was accepted by the target. The event LNET_EVENT_PUT is
1952  * used at the target node to indicate the completion of incoming data
1953  * delivery.
1954  *
1955  * The local events will be logged in the EQ associated with the MD pointed to
1956  * by \a mdh handle. Using a MD without an associated EQ results in these
1957  * events being discarded. In this case, the caller must have another
1958  * mechanism (e.g., a higher level protocol) for determining when it is safe
1959  * to modify the memory region associated with the MD.
1960  *
1961  * Note that LNet does not guarantee the order of LNET_EVENT_SEND and
1962  * LNET_EVENT_ACK, though intuitively ACK should happen after SEND.
1963  *
1964  * \param self Indicates the NID of a local interface through which to send
1965  * the PUT request. Use LNET_NID_ANY to let LNet choose one by itself.
1966  * \param mdh A handle for the MD that describes the memory to be sent. The MD
1967  * must be "free floating" (See LNetMDBind()).
1968  * \param ack Controls whether an acknowledgment is requested.
1969  * Acknowledgments are only sent when they are requested by the initiating
1970  * process and the target MD enables them.
1971  * \param target A process identifier for the target process.
1972  * \param portal The index in the \a target's portal table.
1973  * \param match_bits The match bits to use for MD selection at the target
1974  * process.
1975  * \param offset The offset into the target MD (only used when the target
1976  * MD has the LNET_MD_MANAGE_REMOTE option set).
1977  * \param hdr_data 64 bits of user data that can be included in the message
1978  * header. This data is written to an event queue entry at the target if an
1979  * EQ is present on the matching MD.
1980  *
1981  * \retval  0      Success, and only in this case events will be generated
1982  * and logged to EQ (if it exists).
1983  * \retval -EIO    Simulated failure.
1984  * \retval -ENOMEM Memory allocation failure.
1985  * \retval -ENOENT Invalid MD object.
1986  *
1987  * \see lnet_event_t::hdr_data and lnet_event_kind_t.
1988  */
1989 int
1990 LNetPut(lnet_nid_t self, lnet_handle_md_t mdh, lnet_ack_req_t ack,
1991         lnet_process_id_t target, unsigned int portal,
1992         __u64 match_bits, unsigned int offset,
1993         __u64 hdr_data)
1994 {
1995         struct lnet_msg *msg;
1996         struct lnet_libmd *md;
1997         int cpt;
1998         int rc;
1999
2000         LASSERT(the_lnet.ln_refcount > 0);
2001
2002         if (!list_empty(&the_lnet.ln_test_peers) && /* normally we don't */
2003             fail_peer(target.nid, 1)) { /* shall we now? */
2004                 CERROR("Dropping PUT to %s: simulated failure\n",
2005                        libcfs_id2str(target));
2006                 return -EIO;
2007         }
2008
2009         msg = lnet_msg_alloc();
2010         if (!msg) {
2011                 CERROR("Dropping PUT to %s: ENOMEM on lnet_msg_t\n",
2012                        libcfs_id2str(target));
2013                 return -ENOMEM;
2014         }
2015         msg->msg_vmflush = !!memory_pressure_get();
2016
2017         cpt = lnet_cpt_of_cookie(mdh.cookie);
2018         lnet_res_lock(cpt);
2019
2020         md = lnet_handle2md(&mdh);
2021         if (!md || !md->md_threshold || md->md_me) {
2022                 CERROR("Dropping PUT (%llu:%d:%s): MD (%d) invalid\n",
2023                        match_bits, portal, libcfs_id2str(target),
2024                        !md ? -1 : md->md_threshold);
2025                 if (md && md->md_me)
2026                         CERROR("Source MD also attached to portal %d\n",
2027                                md->md_me->me_portal);
2028                 lnet_res_unlock(cpt);
2029
2030                 lnet_msg_free(msg);
2031                 return -ENOENT;
2032         }
2033
2034         CDEBUG(D_NET, "LNetPut -> %s\n", libcfs_id2str(target));
2035
2036         lnet_msg_attach_md(msg, md, 0, 0);
2037
2038         lnet_prep_send(msg, LNET_MSG_PUT, target, 0, md->md_length);
2039
2040         msg->msg_hdr.msg.put.match_bits = cpu_to_le64(match_bits);
2041         msg->msg_hdr.msg.put.ptl_index = cpu_to_le32(portal);
2042         msg->msg_hdr.msg.put.offset = cpu_to_le32(offset);
2043         msg->msg_hdr.msg.put.hdr_data = hdr_data;
2044
2045         /* NB handles only looked up by creator (no flips) */
2046         if (ack == LNET_ACK_REQ) {
2047                 msg->msg_hdr.msg.put.ack_wmd.wh_interface_cookie =
2048                         the_lnet.ln_interface_cookie;
2049                 msg->msg_hdr.msg.put.ack_wmd.wh_object_cookie =
2050                         md->md_lh.lh_cookie;
2051         } else {
2052                 msg->msg_hdr.msg.put.ack_wmd.wh_interface_cookie =
2053                         LNET_WIRE_HANDLE_COOKIE_NONE;
2054                 msg->msg_hdr.msg.put.ack_wmd.wh_object_cookie =
2055                         LNET_WIRE_HANDLE_COOKIE_NONE;
2056         }
2057
2058         lnet_res_unlock(cpt);
2059
2060         lnet_build_msg_event(msg, LNET_EVENT_SEND);
2061
2062         rc = lnet_send(self, msg, LNET_NID_ANY);
2063         if (rc) {
2064                 CNETERR("Error sending PUT to %s: %d\n",
2065                         libcfs_id2str(target), rc);
2066                 lnet_finalize(NULL, msg, rc);
2067         }
2068
2069         /* completion will be signalled by an event */
2070         return 0;
2071 }
2072 EXPORT_SYMBOL(LNetPut);
2073
2074 lnet_msg_t *
2075 lnet_create_reply_msg(lnet_ni_t *ni, lnet_msg_t *getmsg)
2076 {
2077         /*
2078          * The LND can DMA direct to the GET md (i.e. no REPLY msg).  This
2079          * returns a msg for the LND to pass to lnet_finalize() when the sink
2080          * data has been received.
2081          *
2082          * CAVEAT EMPTOR: 'getmsg' is the original GET, which is freed when
2083          * lnet_finalize() is called on it, so the LND must call this first
2084          */
2085         struct lnet_msg *msg = lnet_msg_alloc();
2086         struct lnet_libmd *getmd = getmsg->msg_md;
2087         lnet_process_id_t peer_id = getmsg->msg_target;
2088         int cpt;
2089
2090         LASSERT(!getmsg->msg_target_is_router);
2091         LASSERT(!getmsg->msg_routing);
2092
2093         if (!msg) {
2094                 CERROR("%s: Dropping REPLY from %s: can't allocate msg\n",
2095                        libcfs_nid2str(ni->ni_nid), libcfs_id2str(peer_id));
2096                 goto drop;
2097         }
2098
2099         cpt = lnet_cpt_of_cookie(getmd->md_lh.lh_cookie);
2100         lnet_res_lock(cpt);
2101
2102         LASSERT(getmd->md_refcount > 0);
2103
2104         if (!getmd->md_threshold) {
2105                 CERROR("%s: Dropping REPLY from %s for inactive MD %p\n",
2106                        libcfs_nid2str(ni->ni_nid), libcfs_id2str(peer_id),
2107                        getmd);
2108                 lnet_res_unlock(cpt);
2109                 goto drop;
2110         }
2111
2112         LASSERT(!getmd->md_offset);
2113
2114         CDEBUG(D_NET, "%s: Reply from %s md %p\n",
2115                libcfs_nid2str(ni->ni_nid), libcfs_id2str(peer_id), getmd);
2116
2117         /* setup information for lnet_build_msg_event */
2118         msg->msg_from = peer_id.nid;
2119         msg->msg_type = LNET_MSG_GET; /* flag this msg as an "optimized" GET */
2120         msg->msg_hdr.src_nid = peer_id.nid;
2121         msg->msg_hdr.payload_length = getmd->md_length;
2122         msg->msg_receiving = 1; /* required by lnet_msg_attach_md */
2123
2124         lnet_msg_attach_md(msg, getmd, getmd->md_offset, getmd->md_length);
2125         lnet_res_unlock(cpt);
2126
2127         cpt = lnet_cpt_of_nid(peer_id.nid);
2128
2129         lnet_net_lock(cpt);
2130         lnet_msg_commit(msg, cpt);
2131         lnet_net_unlock(cpt);
2132
2133         lnet_build_msg_event(msg, LNET_EVENT_REPLY);
2134
2135         return msg;
2136
2137  drop:
2138         cpt = lnet_cpt_of_nid(peer_id.nid);
2139
2140         lnet_net_lock(cpt);
2141         the_lnet.ln_counters[cpt]->drop_count++;
2142         the_lnet.ln_counters[cpt]->drop_length += getmd->md_length;
2143         lnet_net_unlock(cpt);
2144
2145         if (msg)
2146                 lnet_msg_free(msg);
2147
2148         return NULL;
2149 }
2150 EXPORT_SYMBOL(lnet_create_reply_msg);
2151
2152 void
2153 lnet_set_reply_msg_len(lnet_ni_t *ni, lnet_msg_t *reply, unsigned int len)
2154 {
2155         /*
2156          * Set the REPLY length, now the RDMA that elides the REPLY message has
2157          * completed and I know it.
2158          */
2159         LASSERT(reply);
2160         LASSERT(reply->msg_type == LNET_MSG_GET);
2161         LASSERT(reply->msg_ev.type == LNET_EVENT_REPLY);
2162
2163         /*
2164          * NB I trusted my peer to RDMA.  If she tells me she's written beyond
2165          * the end of my buffer, I might as well be dead.
2166          */
2167         LASSERT(len <= reply->msg_ev.mlength);
2168
2169         reply->msg_ev.mlength = len;
2170 }
2171 EXPORT_SYMBOL(lnet_set_reply_msg_len);
2172
2173 /**
2174  * Initiate an asynchronous GET operation.
2175  *
2176  * On the initiator node, an LNET_EVENT_SEND is logged when the GET request
2177  * is sent, and an LNET_EVENT_REPLY is logged when the data returned from
2178  * the target node in the REPLY has been written to local MD.
2179  *
2180  * On the target node, an LNET_EVENT_GET is logged when the GET request
2181  * arrives and is accepted into a MD.
2182  *
2183  * \param self,target,portal,match_bits,offset See the discussion in LNetPut().
2184  * \param mdh A handle for the MD that describes the memory into which the
2185  * requested data will be received. The MD must be "free floating"
2186  * (See LNetMDBind()).
2187  *
2188  * \retval  0      Success, and only in this case events will be generated
2189  * and logged to EQ (if it exists) of the MD.
2190  * \retval -EIO    Simulated failure.
2191  * \retval -ENOMEM Memory allocation failure.
2192  * \retval -ENOENT Invalid MD object.
2193  */
2194 int
2195 LNetGet(lnet_nid_t self, lnet_handle_md_t mdh,
2196         lnet_process_id_t target, unsigned int portal,
2197         __u64 match_bits, unsigned int offset)
2198 {
2199         struct lnet_msg *msg;
2200         struct lnet_libmd *md;
2201         int cpt;
2202         int rc;
2203
2204         LASSERT(the_lnet.ln_refcount > 0);
2205
2206         if (!list_empty(&the_lnet.ln_test_peers) && /* normally we don't */
2207             fail_peer(target.nid, 1)) {   /* shall we now? */
2208                 CERROR("Dropping GET to %s: simulated failure\n",
2209                        libcfs_id2str(target));
2210                 return -EIO;
2211         }
2212
2213         msg = lnet_msg_alloc();
2214         if (!msg) {
2215                 CERROR("Dropping GET to %s: ENOMEM on lnet_msg_t\n",
2216                        libcfs_id2str(target));
2217                 return -ENOMEM;
2218         }
2219
2220         cpt = lnet_cpt_of_cookie(mdh.cookie);
2221         lnet_res_lock(cpt);
2222
2223         md = lnet_handle2md(&mdh);
2224         if (!md || !md->md_threshold || md->md_me) {
2225                 CERROR("Dropping GET (%llu:%d:%s): MD (%d) invalid\n",
2226                        match_bits, portal, libcfs_id2str(target),
2227                        !md ? -1 : md->md_threshold);
2228                 if (md && md->md_me)
2229                         CERROR("REPLY MD also attached to portal %d\n",
2230                                md->md_me->me_portal);
2231
2232                 lnet_res_unlock(cpt);
2233
2234                 lnet_msg_free(msg);
2235                 return -ENOENT;
2236         }
2237
2238         CDEBUG(D_NET, "LNetGet -> %s\n", libcfs_id2str(target));
2239
2240         lnet_msg_attach_md(msg, md, 0, 0);
2241
2242         lnet_prep_send(msg, LNET_MSG_GET, target, 0, 0);
2243
2244         msg->msg_hdr.msg.get.match_bits = cpu_to_le64(match_bits);
2245         msg->msg_hdr.msg.get.ptl_index = cpu_to_le32(portal);
2246         msg->msg_hdr.msg.get.src_offset = cpu_to_le32(offset);
2247         msg->msg_hdr.msg.get.sink_length = cpu_to_le32(md->md_length);
2248
2249         /* NB handles only looked up by creator (no flips) */
2250         msg->msg_hdr.msg.get.return_wmd.wh_interface_cookie =
2251                 the_lnet.ln_interface_cookie;
2252         msg->msg_hdr.msg.get.return_wmd.wh_object_cookie =
2253                 md->md_lh.lh_cookie;
2254
2255         lnet_res_unlock(cpt);
2256
2257         lnet_build_msg_event(msg, LNET_EVENT_SEND);
2258
2259         rc = lnet_send(self, msg, LNET_NID_ANY);
2260         if (rc < 0) {
2261                 CNETERR("Error sending GET to %s: %d\n",
2262                         libcfs_id2str(target), rc);
2263                 lnet_finalize(NULL, msg, rc);
2264         }
2265
2266         /* completion will be signalled by an event */
2267         return 0;
2268 }
2269 EXPORT_SYMBOL(LNetGet);
2270
2271 /**
2272  * Calculate distance to node at \a dstnid.
2273  *
2274  * \param dstnid Target NID.
2275  * \param srcnidp If not NULL, NID of the local interface to reach \a dstnid
2276  * is saved here.
2277  * \param orderp If not NULL, order of the route to reach \a dstnid is saved
2278  * here.
2279  *
2280  * \retval 0 If \a dstnid belongs to a local interface, and reserved option
2281  * local_nid_dist_zero is set, which is the default.
2282  * \retval positives Distance to target NID, i.e. number of hops plus one.
2283  * \retval -EHOSTUNREACH If \a dstnid is not reachable.
2284  */
2285 int
2286 LNetDist(lnet_nid_t dstnid, lnet_nid_t *srcnidp, __u32 *orderp)
2287 {
2288         struct list_head *e;
2289         struct lnet_ni *ni;
2290         lnet_remotenet_t *rnet;
2291         __u32 dstnet = LNET_NIDNET(dstnid);
2292         int hops;
2293         int cpt;
2294         __u32 order = 2;
2295         struct list_head *rn_list;
2296
2297         /*
2298          * if !local_nid_dist_zero, I don't return a distance of 0 ever
2299          * (when lustre sees a distance of 0, it substitutes 0@lo), so I
2300          * keep order 0 free for 0@lo and order 1 free for a local NID
2301          * match
2302          */
2303         LASSERT(the_lnet.ln_refcount > 0);
2304
2305         cpt = lnet_net_lock_current();
2306
2307         list_for_each(e, &the_lnet.ln_nis) {
2308                 ni = list_entry(e, lnet_ni_t, ni_list);
2309
2310                 if (ni->ni_nid == dstnid) {
2311                         if (srcnidp)
2312                                 *srcnidp = dstnid;
2313                         if (orderp) {
2314                                 if (LNET_NETTYP(LNET_NIDNET(dstnid)) == LOLND)
2315                                         *orderp = 0;
2316                                 else
2317                                         *orderp = 1;
2318                         }
2319                         lnet_net_unlock(cpt);
2320
2321                         return local_nid_dist_zero ? 0 : 1;
2322                 }
2323
2324                 if (LNET_NIDNET(ni->ni_nid) == dstnet) {
2325                         /*
2326                          * Check if ni was originally created in
2327                          * current net namespace.
2328                          * If not, assign order above 0xffff0000,
2329                          * to make this ni not a priority.
2330                          */
2331                         if (!net_eq(ni->ni_net_ns, current->nsproxy->net_ns))
2332                                 order += 0xffff0000;
2333
2334                         if (srcnidp)
2335                                 *srcnidp = ni->ni_nid;
2336                         if (orderp)
2337                                 *orderp = order;
2338                         lnet_net_unlock(cpt);
2339                         return 1;
2340                 }
2341
2342                 order++;
2343         }
2344
2345         rn_list = lnet_net2rnethash(dstnet);
2346         list_for_each(e, rn_list) {
2347                 rnet = list_entry(e, lnet_remotenet_t, lrn_list);
2348
2349                 if (rnet->lrn_net == dstnet) {
2350                         lnet_route_t *route;
2351                         lnet_route_t *shortest = NULL;
2352                         __u32 shortest_hops = LNET_UNDEFINED_HOPS;
2353                         __u32 route_hops;
2354
2355                         LASSERT(!list_empty(&rnet->lrn_routes));
2356
2357                         list_for_each_entry(route, &rnet->lrn_routes,
2358                                             lr_list) {
2359                                 route_hops = route->lr_hops;
2360                                 if (route_hops == LNET_UNDEFINED_HOPS)
2361                                         route_hops = 1;
2362                                 if (!shortest ||
2363                                     route_hops < shortest_hops) {
2364                                         shortest = route;
2365                                         shortest_hops = route_hops;
2366                                 }
2367                         }
2368
2369                         LASSERT(shortest);
2370                         hops = shortest_hops;
2371                         if (srcnidp)
2372                                 *srcnidp = shortest->lr_gateway->lp_ni->ni_nid;
2373                         if (orderp)
2374                                 *orderp = order;
2375                         lnet_net_unlock(cpt);
2376                         return hops + 1;
2377                 }
2378                 order++;
2379         }
2380
2381         lnet_net_unlock(cpt);
2382         return -EHOSTUNREACH;
2383 }
2384 EXPORT_SYMBOL(LNetDist);