lustre/ptlrpc/import.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, 2017, 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  * lustre/ptlrpc/import.c
  33  *
  34  * Author: Mike Shaver <shaver@clusterfs.com>
  35  */
  36
  37 #define DEBUG_SUBSYSTEM S_RPC
  38
  39 #include <linux/kthread.h>
  40 #include <linux/delay.h>
  41 #include <obd_support.h>
  42 #include <lustre_ha.h>
  43 #include <lustre_net.h>
  44 #include <lustre_import.h>
  45 #include <lustre_export.h>
  46 #include <obd.h>
  47 #include <obd_cksum.h>
  48 #include <obd_class.h>
  49
  50 #include "ptlrpc_internal.h"
  51
  52 struct ptlrpc_connect_async_args {
  53          __u64 pcaa_peer_committed;
  54         int pcaa_initial_connect;
  55 };
  56
  57 /**
  58  * Updates import \a imp current state to provided \a state value
  59  * Helper function.
  60  */
  61 static void import_set_state_nolock(struct obd_import *imp,
  62                                     enum lustre_imp_state state)
  63 {
  64         switch (state) {
  65         case LUSTRE_IMP_CLOSED:
  66         case LUSTRE_IMP_NEW:
  67         case LUSTRE_IMP_DISCON:
  68         case LUSTRE_IMP_CONNECTING:
  69                 break;
  70         case LUSTRE_IMP_REPLAY_WAIT:
  71                 imp->imp_replay_state = LUSTRE_IMP_REPLAY_LOCKS;
  72                 break;
  73         default:
  74                 imp->imp_replay_state = LUSTRE_IMP_REPLAY;
  75                 break;
  76         }
  77
  78         /* A CLOSED import should remain so. */
  79         if (imp->imp_state == LUSTRE_IMP_CLOSED)
  80                 return;
  81
  82         if (imp->imp_state != LUSTRE_IMP_NEW) {
  83                 CDEBUG(D_HA, "%p %s: changing import state from %s to %s\n",
  84                        imp, obd2cli_tgt(imp->imp_obd),
  85                        ptlrpc_import_state_name(imp->imp_state),
  86                        ptlrpc_import_state_name(state));
  87         }
  88
  89         imp->imp_state = state;
  90         imp->imp_state_hist[imp->imp_state_hist_idx].ish_state = state;
  91         imp->imp_state_hist[imp->imp_state_hist_idx].ish_time =
  92                 ktime_get_real_seconds();
  93         imp->imp_state_hist_idx = (imp->imp_state_hist_idx + 1) %
  94                 IMP_STATE_HIST_LEN;
  95 }
  96
  97 static void import_set_state(struct obd_import *imp,
  98                              enum lustre_imp_state new_state)
  99 {
 100         spin_lock(&imp->imp_lock);
 101         import_set_state_nolock(imp, new_state);
 102         spin_unlock(&imp->imp_lock);
 103 }
 104
 105 void ptlrpc_import_enter_resend(struct obd_import *imp)
 106 {
 107         import_set_state(imp, LUSTRE_IMP_RECOVER);
 108 }
 109 EXPORT_SYMBOL(ptlrpc_import_enter_resend);
 110
 111
 112 static int ptlrpc_connect_interpret(const struct lu_env *env,
 113                                     struct ptlrpc_request *request,
 114                                     void *args, int rc);
 115 int ptlrpc_import_recovery_state_machine(struct obd_import *imp);
 116
 117 /* Only this function is allowed to change the import state when it is
 118  * CLOSED. I would rather refcount the import and free it after
 119  * disconnection like we do with exports. To do that, the client_obd
 120  * will need to save the peer info somewhere other than in the import,
 121  * though. */
 122 int ptlrpc_init_import(struct obd_import *imp)
 123 {
 124         spin_lock(&imp->imp_lock);
 125
 126         imp->imp_generation++;
 127         imp->imp_state =  LUSTRE_IMP_NEW;
 128
 129         spin_unlock(&imp->imp_lock);
 130
 131         return 0;
 132 }
 133 EXPORT_SYMBOL(ptlrpc_init_import);
 134
 135 #define UUID_STR "_UUID"
 136 void deuuidify(char *uuid, const char *prefix, char **uuid_start, int *uuid_len)
 137 {
 138         *uuid_start = !prefix || strncmp(uuid, prefix, strlen(prefix))
 139                 ? uuid : uuid + strlen(prefix);
 140
 141         *uuid_len = strlen(*uuid_start);
 142
 143         if (*uuid_len < strlen(UUID_STR))
 144                 return;
 145
 146         if (!strncmp(*uuid_start + *uuid_len - strlen(UUID_STR),
 147                     UUID_STR, strlen(UUID_STR)))
 148                 *uuid_len -= strlen(UUID_STR);
 149 }
 150
 151 /* Must be called with imp_lock held! */
 152 static void ptlrpc_deactivate_import_nolock(struct obd_import *imp)
 153 {
 154         ENTRY;
 155
 156         assert_spin_locked(&imp->imp_lock);
 157         CDEBUG(D_HA, "setting import %s INVALID\n", obd2cli_tgt(imp->imp_obd));
 158         imp->imp_invalid = 1;
 159         imp->imp_generation++;
 160
 161         ptlrpc_abort_inflight(imp);
 162
 163         EXIT;
 164 }
 165
 166 /**
 167  * Returns true if import was FULL, false if import was already not
 168  * connected.
 169  * @imp - import to be disconnected
 170  * @conn_cnt - connection count (epoch) of the request that timed out
 171  *             and caused the disconnection.  In some cases, multiple
 172  *             inflight requests can fail to a single target (e.g. OST
 173  *             bulk requests) and if one has already caused a reconnection
 174  *             (increasing the import->conn_cnt) the older failure should
 175  *             not also cause a reconnection.  If zero it forces a reconnect.
 176  * @invalid - set import invalid flag
 177  */
 178 int ptlrpc_set_import_discon(struct obd_import *imp,
 179                              __u32 conn_cnt, bool invalid)
 180 {
 181         int rc = 0;
 182
 183         spin_lock(&imp->imp_lock);
 184
 185         if (imp->imp_state == LUSTRE_IMP_FULL &&
 186             (conn_cnt == 0 || conn_cnt == imp->imp_conn_cnt)) {
 187                 char *target_start;
 188                 int   target_len;
 189                 bool  inact = false;
 190
 191                 deuuidify(obd2cli_tgt(imp->imp_obd), NULL,
 192                           &target_start, &target_len);
 193
 194                 import_set_state_nolock(imp, LUSTRE_IMP_DISCON);
 195                 if (imp->imp_replayable) {
 196                         LCONSOLE_WARN("%s: Connection to %.*s (at %s) was "
 197                                "lost; in progress operations using this "
 198                                "service will wait for recovery to complete\n",
 199                                imp->imp_obd->obd_name, target_len, target_start,
 200                                obd_import_nid2str(imp));
 201                 } else {
 202                         LCONSOLE_ERROR_MSG(0x166, "%s: Connection to "
 203                                "%.*s (at %s) was lost; in progress "
 204                                "operations using this service will fail\n",
 205                                imp->imp_obd->obd_name, target_len, target_start,
 206                                obd_import_nid2str(imp));
 207                         if (invalid) {
 208                                 CDEBUG(D_HA, "import %s@%s for %s not "
 209                                        "replayable, auto-deactivating\n",
 210                                        obd2cli_tgt(imp->imp_obd),
 211                                        imp->imp_connection->c_remote_uuid.uuid,
 212                                        imp->imp_obd->obd_name);
 213                                 ptlrpc_deactivate_import_nolock(imp);
 214                                 inact = true;
 215                         }
 216                 }
 217                 spin_unlock(&imp->imp_lock);
 218
 219                 if (obd_dump_on_timeout)
 220                         libcfs_debug_dumplog();
 221
 222                 obd_import_event(imp->imp_obd, imp, IMP_EVENT_DISCON);
 223
 224                 if (inact)
 225                         obd_import_event(imp->imp_obd, imp, IMP_EVENT_INACTIVE);
 226                 rc = 1;
 227         } else {
 228                 spin_unlock(&imp->imp_lock);
 229                 CDEBUG(D_HA, "%s: import %p already %s (conn %u, was %u): %s\n",
 230                        imp->imp_client->cli_name, imp,
 231                        (imp->imp_state == LUSTRE_IMP_FULL &&
 232                         imp->imp_conn_cnt > conn_cnt) ?
 233                        "reconnected" : "not connected", imp->imp_conn_cnt,
 234                        conn_cnt, ptlrpc_import_state_name(imp->imp_state));
 235         }
 236
 237         return rc;
 238 }
 239
 240 /*
 241  * This acts as a barrier; all existing requests are rejected, and
 242  * no new requests will be accepted until the import is valid again.
 243  */
 244 void ptlrpc_deactivate_import(struct obd_import *imp)
 245 {
 246         spin_lock(&imp->imp_lock);
 247         ptlrpc_deactivate_import_nolock(imp);
 248         spin_unlock(&imp->imp_lock);
 249
 250         obd_import_event(imp->imp_obd, imp, IMP_EVENT_INACTIVE);
 251 }
 252 EXPORT_SYMBOL(ptlrpc_deactivate_import);
 253
 254 static time64_t ptlrpc_inflight_deadline(struct ptlrpc_request *req,
 255                                          time64_t now)
 256 {
 257         time64_t dl;
 258
 259         if (!(((req->rq_phase == RQ_PHASE_RPC) && !req->rq_waiting) ||
 260               (req->rq_phase == RQ_PHASE_BULK) ||
 261               (req->rq_phase == RQ_PHASE_NEW)))
 262                 return 0;
 263
 264         if (req->rq_timedout)
 265                 return 0;
 266
 267         if (req->rq_phase == RQ_PHASE_NEW)
 268                 dl = req->rq_sent;
 269         else
 270                 dl = req->rq_deadline;
 271
 272         if (dl <= now)
 273                 return 0;
 274
 275         return dl - now;
 276 }
 277
 278 static time64_t ptlrpc_inflight_timeout(struct obd_import *imp)
 279 {
 280         time64_t now = ktime_get_real_seconds();
 281         struct list_head *tmp, *n;
 282         struct ptlrpc_request *req;
 283         time64_t timeout = 0;
 284
 285         spin_lock(&imp->imp_lock);
 286         list_for_each_safe(tmp, n, &imp->imp_sending_list) {
 287                 req = list_entry(tmp, struct ptlrpc_request, rq_list);
 288                 timeout = max(ptlrpc_inflight_deadline(req, now), timeout);
 289         }
 290         spin_unlock(&imp->imp_lock);
 291         return timeout;
 292 }
 293
 294 /**
 295  * This function will invalidate the import, if necessary, then block
 296  * for all the RPC completions, and finally notify the obd to
 297  * invalidate its state (ie cancel locks, clear pending requests,
 298  * etc).
 299  */
 300 void ptlrpc_invalidate_import(struct obd_import *imp)
 301 {
 302         struct list_head *tmp, *n;
 303         struct ptlrpc_request *req;
 304         time64_t timeout;
 305         int rc;
 306
 307         atomic_inc(&imp->imp_inval_count);
 308
 309         if (!imp->imp_invalid || imp->imp_obd->obd_no_recov)
 310                 ptlrpc_deactivate_import(imp);
 311
 312         if (OBD_FAIL_PRECHECK(OBD_FAIL_PTLRPC_CONNECT_RACE)) {
 313                 OBD_RACE(OBD_FAIL_PTLRPC_CONNECT_RACE);
 314                 msleep(10 * MSEC_PER_SEC);
 315         }
 316         CFS_FAIL_TIMEOUT(OBD_FAIL_MGS_CONNECT_NET, 3 * cfs_fail_val / 2);
 317         LASSERT(imp->imp_invalid);
 318
 319         /* Wait forever until inflight == 0. We really can't do it another
 320          * way because in some cases we need to wait for very long reply
 321          * unlink. We can't do anything before that because there is really
 322          * no guarantee that some rdma transfer is not in progress right now.
 323          */
 324         do {
 325                 long timeout_jiffies;
 326
 327                 /* Calculate max timeout for waiting on rpcs to error
 328                  * out. Use obd_timeout if calculated value is smaller
 329                  * than it.
 330                  */
 331                 if (!OBD_FAIL_CHECK(OBD_FAIL_PTLRPC_LONG_REPL_UNLINK)) {
 332                         timeout = ptlrpc_inflight_timeout(imp);
 333                         timeout += div_u64(timeout, 3);
 334
 335                         if (timeout == 0)
 336                                 timeout = obd_timeout;
 337                 } else {
 338                         /* decrease the interval to increase race condition */
 339                         timeout = 1;
 340                 }
 341
 342                 CDEBUG(D_RPCTRACE, "Sleeping %llds for inflight to error out\n",
 343                        timeout);
 344
 345                 /* Wait for all requests to error out and call completion
 346                  * callbacks. Cap it at obd_timeout -- these should all
 347                  * have been locally cancelled by ptlrpc_abort_inflight.
 348                  */
 349                 timeout_jiffies = max_t(long, cfs_time_seconds(timeout), 1);
 350                 rc = wait_event_idle_timeout(
 351                                     imp->imp_recovery_waitq,
 352                                     (atomic_read(&imp->imp_inflight) == 0),
 353                                     timeout_jiffies);
 354
 355                 if (rc == 0) {
 356                         const char *cli_tgt = obd2cli_tgt(imp->imp_obd);
 357
 358                         CERROR("%s: timeout waiting for callback (%d != 0)\n",
 359                                cli_tgt, atomic_read(&imp->imp_inflight));
 360
 361                         spin_lock(&imp->imp_lock);
 362                         if (atomic_read(&imp->imp_inflight) == 0) {
 363                                 int count = atomic_read(&imp->imp_unregistering);
 364
 365                                 /* We know that "unregistering" rpcs only can
 366                                  * survive in sending or delaying lists (they
 367                                  * maybe waiting for long reply unlink in
 368                                  * sluggish nets). Let's check this. If there
 369                                  * is no inflight and unregistering != 0, this
 370                                  * is bug. */
 371                                 LASSERTF(count == 0, "Some RPCs are still "
 372                                          "unregistering: %d\n", count);
 373
 374                                 /* Let's save one loop as soon as inflight have
 375                                  * dropped to zero. No new inflights possible at
 376                                  * this point. */
 377                                 rc = 1;
 378                         } else {
 379                                 list_for_each_safe(tmp, n,
 380                                                    &imp->imp_sending_list) {
 381                                         req = list_entry(tmp,
 382                                                          struct ptlrpc_request,
 383                                                          rq_list);
 384                                         DEBUG_REQ(D_ERROR, req,
 385                                                   "still on sending list");
 386                                 }
 387                                 list_for_each_safe(tmp, n,
 388                                                    &imp->imp_delayed_list) {
 389                                         req = list_entry(tmp,
 390                                                          struct ptlrpc_request,
 391                                                          rq_list);
 392                                         DEBUG_REQ(D_ERROR, req,
 393                                                   "still on delayed list");
 394                                 }
 395
 396                                 CERROR("%s: Unregistering RPCs found (%d). "
 397                                        "Network is sluggish? Waiting for them "
 398                                        "to error out.\n", cli_tgt,
 399                                        atomic_read(&imp->imp_unregistering));
 400                         }
 401                         spin_unlock(&imp->imp_lock);
 402                 }
 403         } while (rc == 0);
 404
 405         /*
 406          * Let's additionally check that no new rpcs added to import in
 407          * "invalidate" state.
 408          */
 409         LASSERT(atomic_read(&imp->imp_inflight) == 0);
 410         obd_import_event(imp->imp_obd, imp, IMP_EVENT_INVALIDATE);
 411         sptlrpc_import_flush_all_ctx(imp);
 412
 413         atomic_dec(&imp->imp_inval_count);
 414         wake_up(&imp->imp_recovery_waitq);
 415 }
 416 EXPORT_SYMBOL(ptlrpc_invalidate_import);
 417
 418 /* unset imp_invalid */
 419 void ptlrpc_activate_import(struct obd_import *imp, bool set_state_full)
 420 {
 421         struct obd_device *obd = imp->imp_obd;
 422
 423         spin_lock(&imp->imp_lock);
 424         if (imp->imp_deactive != 0) {
 425                 LASSERT(imp->imp_state != LUSTRE_IMP_FULL);
 426                 if (imp->imp_state != LUSTRE_IMP_DISCON)
 427                         import_set_state_nolock(imp, LUSTRE_IMP_DISCON);
 428                 spin_unlock(&imp->imp_lock);
 429                 return;
 430         }
 431         if (set_state_full)
 432                 import_set_state_nolock(imp, LUSTRE_IMP_FULL);
 433
 434         imp->imp_invalid = 0;
 435
 436         spin_unlock(&imp->imp_lock);
 437         obd_import_event(obd, imp, IMP_EVENT_ACTIVE);
 438 }
 439 EXPORT_SYMBOL(ptlrpc_activate_import);
 440
 441 void ptlrpc_pinger_force(struct obd_import *imp)
 442 {
 443         CDEBUG(D_HA, "%s: waking up pinger s:%s\n", obd2cli_tgt(imp->imp_obd),
 444                ptlrpc_import_state_name(imp->imp_state));
 445
 446         spin_lock(&imp->imp_lock);
 447         imp->imp_force_verify = 1;
 448         spin_unlock(&imp->imp_lock);
 449
 450         if (imp->imp_state != LUSTRE_IMP_CONNECTING)
 451                 ptlrpc_pinger_wake_up();
 452 }
 453 EXPORT_SYMBOL(ptlrpc_pinger_force);
 454
 455 void ptlrpc_fail_import(struct obd_import *imp, __u32 conn_cnt)
 456 {
 457         ENTRY;
 458
 459         LASSERT(!imp->imp_dlm_fake);
 460
 461         if (ptlrpc_set_import_discon(imp, conn_cnt, true))
 462                 ptlrpc_pinger_force(imp);
 463
 464         EXIT;
 465 }
 466
 467 int ptlrpc_reconnect_import(struct obd_import *imp)
 468 {
 469 #ifdef CONFIG_LUSTRE_FS_PINGER
 470         long timeout_jiffies = cfs_time_seconds(obd_timeout);
 471         int rc;
 472
 473         ptlrpc_pinger_force(imp);
 474
 475         CDEBUG(D_HA, "%s: recovery started, waiting %u seconds\n",
 476                obd2cli_tgt(imp->imp_obd), obd_timeout);
 477
 478         rc = wait_event_idle_timeout(imp->imp_recovery_waitq,
 479                                      !ptlrpc_import_in_recovery(imp),
 480                                      timeout_jiffies);
 481         if (rc == 0)
 482                 rc = -ETIMEDOUT;
 483         else
 484                 rc = 0;
 485         CDEBUG(D_HA, "%s: recovery finished s:%s\n", obd2cli_tgt(imp->imp_obd),
 486                ptlrpc_import_state_name(imp->imp_state));
 487         return rc;
 488 #else
 489         ptlrpc_set_import_discon(imp, 0, false);
 490         /* Force a new connect attempt */
 491         ptlrpc_invalidate_import(imp);
 492         /* Do a fresh connect next time by zeroing the handle */
 493         ptlrpc_disconnect_import(imp, 1);
 494         /* Wait for all invalidate calls to finish */
 495         if (atomic_read(&imp->imp_inval_count) > 0) {
 496                 int rc;
 497
 498                 rc = l_wait_event_abortable(
 499                         imp->imp_recovery_waitq,
 500                         (atomic_read(&imp->imp_inval_count) == 0));
 501                 if (rc)
 502                         CERROR("Interrupted, inval=%d\n",
 503                                atomic_read(&imp->imp_inval_count));
 504         }
 505
 506         /* Allow reconnect attempts */
 507         imp->imp_obd->obd_no_recov = 0;
 508         /* Remove 'invalid' flag */
 509         ptlrpc_activate_import(imp, false);
 510         /* Attempt a new connect */
 511         ptlrpc_recover_import(imp, NULL, 0);
 512         return 0;
 513 #endif
 514 }
 515 EXPORT_SYMBOL(ptlrpc_reconnect_import);
 516
 517 /**
 518  * Connection on import \a imp is changed to another one (if more than one is
 519  * present). We typically chose connection that we have not tried to connect to
 520  * the longest
 521  */
 522 static int import_select_connection(struct obd_import *imp)
 523 {
 524         struct obd_import_conn *imp_conn = NULL, *conn;
 525         struct obd_export *dlmexp;
 526         char *target_start;
 527         int target_len, tried_all = 1;
 528         int rc = 0;
 529         ENTRY;
 530
 531         spin_lock(&imp->imp_lock);
 532
 533         if (list_empty(&imp->imp_conn_list)) {
 534                 rc = -EINVAL;
 535                 CERROR("%s: no connections available: rc = %d\n",
 536                        imp->imp_obd->obd_name, rc);
 537                 GOTO(out_unlock, rc);
 538         }
 539
 540         list_for_each_entry(conn, &imp->imp_conn_list, oic_item) {
 541                 CDEBUG(D_HA, "%s: connect to NID %s last attempt %lld\n",
 542                        imp->imp_obd->obd_name,
 543                        libcfs_nid2str(conn->oic_conn->c_peer.nid),
 544                        conn->oic_last_attempt);
 545
 546                 /* If we have not tried this connection since
 547                  * the last successful attempt, go with this one
 548                  */
 549                 if ((conn->oic_last_attempt == 0) ||
 550                     conn->oic_last_attempt <= imp->imp_last_success_conn) {
 551                         imp_conn = conn;
 552                         tried_all = 0;
 553                         break;
 554                 }
 555
 556                 /* If all of the connections have already been tried
 557                  * since the last successful connection; just choose the
 558                  * least recently used
 559                  */
 560                 if (!imp_conn)
 561                         imp_conn = conn;
 562                 else if (imp_conn->oic_last_attempt > conn->oic_last_attempt)
 563                         imp_conn = conn;
 564         }
 565
 566         /* if not found, simply choose the current one */
 567         if (!imp_conn || imp->imp_force_reconnect) {
 568                 LASSERT(imp->imp_conn_current);
 569                 imp_conn = imp->imp_conn_current;
 570                 tried_all = 0;
 571         }
 572         LASSERT(imp_conn->oic_conn);
 573
 574         /* If we've tried everything, and we're back to the beginning of the
 575          * list, increase our timeout and try again. It will be reset when
 576          * we do finally connect. (FIXME: really we should wait for all network
 577          * state associated with the last connection attempt to drain before
 578          * trying to reconnect on it.)
 579          */
 580         if (tried_all && (imp->imp_conn_list.next == &imp_conn->oic_item)) {
 581                 struct adaptive_timeout *at = &imp->imp_at.iat_net_latency;
 582
 583                 if (at_get(at) < CONNECTION_SWITCH_MAX) {
 584                         at_measured(at, at_get(at) + CONNECTION_SWITCH_INC);
 585                         if (at_get(at) > CONNECTION_SWITCH_MAX)
 586                                 at_reset(at, CONNECTION_SWITCH_MAX);
 587                 }
 588                 LASSERT(imp_conn->oic_last_attempt);
 589                 CDEBUG(D_HA,
 590                        "%s: tried all connections, increasing latency to %ds\n",
 591                        imp->imp_obd->obd_name, at_get(at));
 592         }
 593
 594         imp_conn->oic_last_attempt = ktime_get_seconds();
 595
 596         /* switch connection, don't mind if it's same as the current one */
 597         if (imp->imp_connection)
 598                 ptlrpc_connection_put(imp->imp_connection);
 599         imp->imp_connection = ptlrpc_connection_addref(imp_conn->oic_conn);
 600
 601         dlmexp = class_conn2export(&imp->imp_dlm_handle);
 602         if (!dlmexp)
 603                 GOTO(out_unlock, rc = -EINVAL);
 604         if (dlmexp->exp_connection)
 605                 ptlrpc_connection_put(dlmexp->exp_connection);
 606         dlmexp->exp_connection = ptlrpc_connection_addref(imp_conn->oic_conn);
 607         class_export_put(dlmexp);
 608
 609         if (imp->imp_conn_current != imp_conn) {
 610                 if (imp->imp_conn_current) {
 611                         deuuidify(obd2cli_tgt(imp->imp_obd), NULL,
 612                                   &target_start, &target_len);
 613
 614                         CDEBUG(D_HA, "%s: Connection changing to"
 615                                " %.*s (at %s)\n",
 616                                imp->imp_obd->obd_name,
 617                                target_len, target_start,
 618                                libcfs_nid2str(imp_conn->oic_conn->c_peer.nid));
 619                 }
 620
 621                 imp->imp_conn_current = imp_conn;
 622         }
 623
 624         /* The below message is checked in conf-sanity.sh test_35[ab] */
 625         CDEBUG(D_HA, "%s: import %p using connection %s/%s\n",
 626                imp->imp_obd->obd_name, imp, imp_conn->oic_uuid.uuid,
 627                libcfs_nid2str(imp_conn->oic_conn->c_peer.nid));
 628
 629 out_unlock:
 630         spin_unlock(&imp->imp_lock);
 631         RETURN(rc);
 632 }
 633
 634 /*
 635  * must be called under imp_lock
 636  */
 637 static int ptlrpc_first_transno(struct obd_import *imp, __u64 *transno)
 638 {
 639         struct ptlrpc_request   *req;
 640         struct list_head        *tmp;
 641
 642         /* The requests in committed_list always have smaller transnos than
 643          * the requests in replay_list */
 644         if (!list_empty(&imp->imp_committed_list)) {
 645                 tmp = imp->imp_committed_list.next;
 646                 req = list_entry(tmp, struct ptlrpc_request, rq_replay_list);
 647                 *transno = req->rq_transno;
 648                 if (req->rq_transno == 0) {
 649                         DEBUG_REQ(D_ERROR, req,
 650                                   "zero transno in committed_list");
 651                         LBUG();
 652                 }
 653                 return 1;
 654         }
 655         if (!list_empty(&imp->imp_replay_list)) {
 656                 tmp = imp->imp_replay_list.next;
 657                 req = list_entry(tmp, struct ptlrpc_request, rq_replay_list);
 658                 *transno = req->rq_transno;
 659                 if (req->rq_transno == 0) {
 660                         DEBUG_REQ(D_ERROR, req, "zero transno in replay_list");
 661                         LBUG();
 662                 }
 663                 return 1;
 664         }
 665         return 0;
 666 }
 667
 668 int ptlrpc_connect_import(struct obd_import *imp)
 669 {
 670         spin_lock(&imp->imp_lock);
 671         return ptlrpc_connect_import_locked(imp);
 672 }
 673
 674 /**
 675  * Attempt to (re)connect import \a imp. This includes all preparations,
 676  * initializing CONNECT RPC request and passing it to ptlrpcd for
 677  * actual sending.
 678  *
 679  * Assumes imp->imp_lock is held, and releases it.
 680  *
 681  * Returns 0 on success or error code.
 682  */
 683 int ptlrpc_connect_import_locked(struct obd_import *imp)
 684 {
 685         struct obd_device *obd = imp->imp_obd;
 686         int initial_connect = 0;
 687         int set_transno = 0;
 688         __u64 committed_before_reconnect = 0;
 689         struct ptlrpc_request *request;
 690         struct obd_connect_data ocd;
 691         char *bufs[] = { NULL,
 692                          obd2cli_tgt(imp->imp_obd),
 693                          obd->obd_uuid.uuid,
 694                          (char *)&imp->imp_dlm_handle,
 695                          (char *)&ocd,
 696                          NULL };
 697         struct ptlrpc_connect_async_args *aa;
 698         int rc;
 699         ENTRY;
 700
 701         assert_spin_locked(&imp->imp_lock);
 702
 703         if (imp->imp_state == LUSTRE_IMP_CLOSED) {
 704                 spin_unlock(&imp->imp_lock);
 705                 CERROR("can't connect to a closed import\n");
 706                 RETURN(-EINVAL);
 707         } else if (imp->imp_state == LUSTRE_IMP_FULL) {
 708                 spin_unlock(&imp->imp_lock);
 709                 CERROR("already connected\n");
 710                 RETURN(0);
 711         } else if (imp->imp_state == LUSTRE_IMP_CONNECTING ||
 712                    imp->imp_state == LUSTRE_IMP_EVICTED ||
 713                    imp->imp_connected) {
 714                 spin_unlock(&imp->imp_lock);
 715                 CERROR("already connecting\n");
 716                 RETURN(-EALREADY);
 717         }
 718
 719         import_set_state_nolock(imp, LUSTRE_IMP_CONNECTING);
 720
 721         imp->imp_conn_cnt++;
 722         imp->imp_resend_replay = 0;
 723
 724         if (!lustre_handle_is_used(&imp->imp_remote_handle))
 725                 initial_connect = 1;
 726         else
 727                 committed_before_reconnect = imp->imp_peer_committed_transno;
 728
 729         set_transno = ptlrpc_first_transno(imp,
 730                                            &imp->imp_connect_data.ocd_transno);
 731         spin_unlock(&imp->imp_lock);
 732
 733         rc = import_select_connection(imp);
 734         if (rc)
 735                 GOTO(out, rc);
 736
 737         rc = sptlrpc_import_sec_adapt(imp, NULL, NULL);
 738         if (rc)
 739                 GOTO(out, rc);
 740
 741         /* Reset connect flags to the originally requested flags, in case
 742          * the server is updated on-the-fly we will get the new features. */
 743         ocd = imp->imp_connect_data;
 744         ocd.ocd_connect_flags = imp->imp_connect_flags_orig;
 745         ocd.ocd_connect_flags2 = imp->imp_connect_flags2_orig;
 746         /* Reset ocd_version each time so the server knows the exact versions */
 747         ocd.ocd_version = LUSTRE_VERSION_CODE;
 748         imp->imp_msghdr_flags &= ~MSGHDR_AT_SUPPORT;
 749         imp->imp_msghdr_flags &= ~MSGHDR_CKSUM_INCOMPAT18;
 750
 751         rc = obd_reconnect(NULL, imp->imp_obd->obd_self_export, obd,
 752                            &obd->obd_uuid, &ocd, NULL);
 753         if (rc)
 754                 GOTO(out, rc);
 755
 756         request = ptlrpc_request_alloc(imp, &RQF_MDS_CONNECT);
 757         if (request == NULL)
 758                 GOTO(out, rc = -ENOMEM);
 759
 760         /* get SELinux policy info if any */
 761         rc = sptlrpc_get_sepol(request);
 762         if (rc < 0) {
 763                 ptlrpc_request_free(request);
 764                 GOTO(out, rc);
 765         }
 766
 767         bufs[5] = request->rq_sepol;
 768
 769         req_capsule_set_size(&request->rq_pill, &RMF_SELINUX_POL, RCL_CLIENT,
 770                              strlen(request->rq_sepol) ?
 771                              strlen(request->rq_sepol) + 1 : 0);
 772
 773         rc = ptlrpc_request_bufs_pack(request, LUSTRE_OBD_VERSION,
 774                                       imp->imp_connect_op, bufs, NULL);
 775         if (rc) {
 776                 ptlrpc_request_free(request);
 777                 GOTO(out, rc);
 778         }
 779
 780         /* Report the rpc service time to the server so that it knows how long
 781          * to wait for clients to join recovery */
 782         lustre_msg_set_service_timeout(request->rq_reqmsg,
 783                                        at_timeout2est(request->rq_timeout));
 784
 785         /* The amount of time we give the server to process the connect req.
 786          * import_select_connection will increase the net latency on
 787          * repeated reconnect attempts to cover slow networks.
 788          * We override/ignore the server rpc completion estimate here,
 789          * which may be large if this is a reconnect attempt */
 790         request->rq_timeout = INITIAL_CONNECT_TIMEOUT;
 791         lustre_msg_set_timeout(request->rq_reqmsg, request->rq_timeout);
 792
 793         request->rq_no_resend = request->rq_no_delay = 1;
 794         request->rq_send_state = LUSTRE_IMP_CONNECTING;
 795         /* Allow a slightly larger reply for future growth compatibility */
 796         req_capsule_set_size(&request->rq_pill, &RMF_CONNECT_DATA, RCL_SERVER,
 797                              sizeof(struct obd_connect_data)+16*sizeof(__u64));
 798         ptlrpc_request_set_replen(request);
 799         request->rq_interpret_reply = ptlrpc_connect_interpret;
 800
 801         aa = ptlrpc_req_async_args(aa, request);
 802         memset(aa, 0, sizeof *aa);
 803
 804         aa->pcaa_peer_committed = committed_before_reconnect;
 805         aa->pcaa_initial_connect = initial_connect;
 806
 807         if (aa->pcaa_initial_connect) {
 808                 spin_lock(&imp->imp_lock);
 809                 imp->imp_replayable = 1;
 810                 spin_unlock(&imp->imp_lock);
 811                 lustre_msg_add_op_flags(request->rq_reqmsg,
 812                                         MSG_CONNECT_INITIAL);
 813         }
 814
 815         if (set_transno)
 816                 lustre_msg_add_op_flags(request->rq_reqmsg,
 817                                         MSG_CONNECT_TRANSNO);
 818
 819         DEBUG_REQ(D_RPCTRACE, request, "(re)connect request (timeout %d)",
 820                   request->rq_timeout);
 821         ptlrpcd_add_req(request);
 822         rc = 0;
 823 out:
 824         if (rc != 0)
 825                 import_set_state(imp, LUSTRE_IMP_DISCON);
 826
 827         RETURN(rc);
 828 }
 829 EXPORT_SYMBOL(ptlrpc_connect_import);
 830
 831 static void ptlrpc_maybe_ping_import_soon(struct obd_import *imp)
 832 {
 833         int force_verify;
 834
 835         spin_lock(&imp->imp_lock);
 836         force_verify = imp->imp_force_verify != 0;
 837         spin_unlock(&imp->imp_lock);
 838
 839         if (force_verify)
 840                 ptlrpc_pinger_wake_up();
 841 }
 842
 843 static int ptlrpc_busy_reconnect(int rc)
 844 {
 845         return (rc == -EBUSY) || (rc == -EAGAIN);
 846 }
 847
 848 static int ptlrpc_connect_set_flags(struct obd_import *imp,
 849                                     struct obd_connect_data *ocd,
 850                                     __u64 old_connect_flags,
 851                                     struct obd_export *exp, int init_connect)
 852 {
 853         static bool warned;
 854         struct client_obd *cli = &imp->imp_obd->u.cli;
 855
 856         spin_lock(&imp->imp_lock);
 857         list_move(&imp->imp_conn_current->oic_item,
 858                   &imp->imp_conn_list);
 859         imp->imp_last_success_conn =
 860                 imp->imp_conn_current->oic_last_attempt;
 861
 862         spin_unlock(&imp->imp_lock);
 863
 864         if (!warned && (ocd->ocd_connect_flags & OBD_CONNECT_VERSION) &&
 865             (ocd->ocd_version > LUSTRE_VERSION_CODE +
 866                                 LUSTRE_VERSION_OFFSET_WARN ||
 867              ocd->ocd_version < LUSTRE_VERSION_CODE -
 868                                 LUSTRE_VERSION_OFFSET_WARN)) {
 869                 /* Sigh, some compilers do not like #ifdef in the middle
 870                    of macro arguments */
 871                 const char *older = "older than client. "
 872                                     "Consider upgrading server";
 873                 const char *newer = "newer than client. "
 874                                     "Consider upgrading client";
 875
 876                 LCONSOLE_WARN("Server %s version (%d.%d.%d.%d) "
 877                               "is much %s (%s)\n",
 878                               obd2cli_tgt(imp->imp_obd),
 879                               OBD_OCD_VERSION_MAJOR(ocd->ocd_version),
 880                               OBD_OCD_VERSION_MINOR(ocd->ocd_version),
 881                               OBD_OCD_VERSION_PATCH(ocd->ocd_version),
 882                               OBD_OCD_VERSION_FIX(ocd->ocd_version),
 883                               ocd->ocd_version > LUSTRE_VERSION_CODE ?
 884                               newer : older, LUSTRE_VERSION_STRING);
 885                 warned = true;
 886         }
 887
 888         if (ocd->ocd_connect_flags & OBD_CONNECT_CKSUM) {
 889                 /* We sent to the server ocd_cksum_types with bits set
 890                  * for algorithms we understand. The server masked off
 891                  * the checksum types it doesn't support */
 892                 if ((ocd->ocd_cksum_types &
 893                      obd_cksum_types_supported_client()) == 0) {
 894                         LCONSOLE_ERROR("The negotiation of the checksum "
 895                                        "alogrithm to use with server %s "
 896                                        "failed (%x/%x)\n",
 897                                        obd2cli_tgt(imp->imp_obd),
 898                                        ocd->ocd_cksum_types,
 899                                        obd_cksum_types_supported_client());
 900                         return -EPROTO;
 901                 } else {
 902                         cli->cl_supp_cksum_types = ocd->ocd_cksum_types;
 903                 }
 904         } else {
 905                 /* The server does not support OBD_CONNECT_CKSUM.
 906                  * Enforce ADLER for backward compatibility*/
 907                 cli->cl_supp_cksum_types = OBD_CKSUM_ADLER;
 908         }
 909         cli->cl_cksum_type = obd_cksum_type_select(imp->imp_obd->obd_name,
 910                                                   cli->cl_supp_cksum_types,
 911                                                   cli->cl_preferred_cksum_type);
 912
 913         if (ocd->ocd_connect_flags & OBD_CONNECT_BRW_SIZE)
 914                 cli->cl_max_pages_per_rpc =
 915                         min(ocd->ocd_brw_size >> PAGE_SHIFT,
 916                             cli->cl_max_pages_per_rpc);
 917         else if (imp->imp_connect_op == MDS_CONNECT ||
 918                  imp->imp_connect_op == MGS_CONNECT)
 919                 cli->cl_max_pages_per_rpc = 1;
 920
 921         LASSERT((cli->cl_max_pages_per_rpc <= PTLRPC_MAX_BRW_PAGES) &&
 922                 (cli->cl_max_pages_per_rpc > 0));
 923
 924         client_adjust_max_dirty(cli);
 925
 926         /* Update client max modify RPCs in flight with value returned
 927          * by the server */
 928         if (ocd->ocd_connect_flags & OBD_CONNECT_MULTIMODRPCS)
 929                 cli->cl_max_mod_rpcs_in_flight = min(
 930                                         cli->cl_max_mod_rpcs_in_flight,
 931                                         ocd->ocd_maxmodrpcs);
 932         else
 933                 cli->cl_max_mod_rpcs_in_flight = 1;
 934
 935         /* Reset ns_connect_flags only for initial connect. It might be
 936          * changed in while using FS and if we reset it in reconnect
 937          * this leads to losing user settings done before such as
 938          * disable lru_resize, etc. */
 939         if (old_connect_flags != exp_connect_flags(exp) || init_connect) {
 940                 struct ldlm_namespace *ns = imp->imp_obd->obd_namespace;
 941                 __u64 changed_flags;
 942
 943                 changed_flags =
 944                         ns->ns_connect_flags ^ ns->ns_orig_connect_flags;
 945                 CDEBUG(D_HA, "%s: Resetting ns_connect_flags to server "
 946                              "flags: %#llx\n", imp->imp_obd->obd_name,
 947                              ocd->ocd_connect_flags);
 948                 ns->ns_connect_flags = (ns->ns_connect_flags & changed_flags) |
 949                                       (ocd->ocd_connect_flags & ~changed_flags);
 950                 ns->ns_orig_connect_flags = ocd->ocd_connect_flags;
 951         }
 952
 953         if (ocd->ocd_connect_flags & OBD_CONNECT_AT)
 954                 /* We need a per-message support flag, because
 955                  * a. we don't know if the incoming connect reply
 956                  *    supports AT or not (in reply_in_callback)
 957                  *    until we unpack it.
 958                  * b. failovered server means export and flags are gone
 959                  *    (in ptlrpc_send_reply).
 960                  *    Can only be set when we know AT is supported at
 961                  *    both ends */
 962                 imp->imp_msghdr_flags |= MSGHDR_AT_SUPPORT;
 963         else
 964                 imp->imp_msghdr_flags &= ~MSGHDR_AT_SUPPORT;
 965
 966         imp->imp_msghdr_flags |= MSGHDR_CKSUM_INCOMPAT18;
 967
 968         return 0;
 969 }
 970
 971 /**
 972  * Add all replay requests back to unreplied list before start replay,
 973  * so that we can make sure the known replied XID is always increased
 974  * only even if when replaying requests.
 975  */
 976 static void ptlrpc_prepare_replay(struct obd_import *imp)
 977 {
 978         struct ptlrpc_request *req;
 979
 980         if (imp->imp_state != LUSTRE_IMP_REPLAY ||
 981             imp->imp_resend_replay)
 982                 return;
 983
 984         /* If the server was restart during repaly, the requests may
 985          * have been added to the unreplied list in former replay. */
 986         spin_lock(&imp->imp_lock);
 987
 988         list_for_each_entry(req, &imp->imp_committed_list, rq_replay_list) {
 989                 if (list_empty(&req->rq_unreplied_list))
 990                         ptlrpc_add_unreplied(req);
 991         }
 992
 993         list_for_each_entry(req, &imp->imp_replay_list, rq_replay_list) {
 994                 if (list_empty(&req->rq_unreplied_list))
 995                         ptlrpc_add_unreplied(req);
 996         }
 997
 998         imp->imp_known_replied_xid = ptlrpc_known_replied_xid(imp);
 999         spin_unlock(&imp->imp_lock);
1000 }
1001
1002 /**
1003  * interpret_reply callback for connect RPCs.
1004  * Looks into returned status of connect operation and decides
1005  * what to do with the import - i.e enter recovery, promote it to
1006  * full state for normal operations of disconnect it due to an error.
1007  */
1008 static int ptlrpc_connect_interpret(const struct lu_env *env,
1009                                     struct ptlrpc_request *request,
1010                                     void *data, int rc)
1011 {
1012         struct ptlrpc_connect_async_args *aa = data;
1013         struct obd_import *imp = request->rq_import;
1014         struct lustre_handle old_hdl;
1015         __u64 old_connect_flags;
1016         timeout_t service_timeout;
1017         int msg_flags;
1018         struct obd_connect_data *ocd;
1019         struct obd_export *exp = NULL;
1020         int ret;
1021         ENTRY;
1022
1023         spin_lock(&imp->imp_lock);
1024         if (imp->imp_state == LUSTRE_IMP_CLOSED) {
1025                 imp->imp_connect_tried = 1;
1026                 spin_unlock(&imp->imp_lock);
1027                 RETURN(0);
1028         }
1029
1030         imp->imp_connect_error = rc;
1031         if (rc) {
1032                 struct ptlrpc_request *free_req;
1033                 struct ptlrpc_request *tmp;
1034
1035                 /* abort all delayed requests initiated connection */
1036                 list_for_each_entry_safe(free_req, tmp, &imp->imp_delayed_list,
1037                                          rq_list) {
1038                         spin_lock(&free_req->rq_lock);
1039                         if (free_req->rq_no_resend) {
1040                                 free_req->rq_err = 1;
1041                                 free_req->rq_status = -EIO;
1042                                 ptlrpc_client_wake_req(free_req);
1043                         }
1044                         spin_unlock(&free_req->rq_lock);
1045                 }
1046
1047                 /* if this reconnect to busy export - not need select new target
1048                  * for connecting*/
1049                 imp->imp_force_reconnect = ptlrpc_busy_reconnect(rc);
1050                 spin_unlock(&imp->imp_lock);
1051                 ptlrpc_maybe_ping_import_soon(imp);
1052                 GOTO(out, rc);
1053         }
1054
1055         /* LU-7558: indicate that we are interpretting connect reply,
1056          * pltrpc_connect_import() will not try to reconnect until
1057          * interpret will finish. */
1058         imp->imp_connected = 1;
1059         spin_unlock(&imp->imp_lock);
1060
1061         LASSERT(imp->imp_conn_current);
1062
1063         msg_flags = lustre_msg_get_op_flags(request->rq_repmsg);
1064
1065         ret = req_capsule_get_size(&request->rq_pill, &RMF_CONNECT_DATA,
1066                                    RCL_SERVER);
1067         /* server replied obd_connect_data is always bigger */
1068         ocd = req_capsule_server_sized_get(&request->rq_pill,
1069                                            &RMF_CONNECT_DATA, ret);
1070
1071         if (ocd == NULL) {
1072                 CERROR("%s: no connect data from server\n",
1073                        imp->imp_obd->obd_name);
1074                 rc = -EPROTO;
1075                 GOTO(out, rc);
1076         }
1077
1078         spin_lock(&imp->imp_lock);
1079
1080         /* All imports are pingable */
1081         imp->imp_pingable = 1;
1082         imp->imp_force_reconnect = 0;
1083         imp->imp_force_verify = 0;
1084
1085         imp->imp_connect_data = *ocd;
1086
1087         CDEBUG(D_HA, "%s: connect to target with instance %u\n",
1088                imp->imp_obd->obd_name, ocd->ocd_instance);
1089         exp = class_conn2export(&imp->imp_dlm_handle);
1090
1091         spin_unlock(&imp->imp_lock);
1092
1093         if (!exp) {
1094                 /* This could happen if export is cleaned during the
1095                    connect attempt */
1096                 CERROR("%s: missing export after connect\n",
1097                        imp->imp_obd->obd_name);
1098                 GOTO(out, rc = -ENODEV);
1099         }
1100
1101         /* check that server granted subset of flags we asked for. */
1102         if ((ocd->ocd_connect_flags & imp->imp_connect_flags_orig) !=
1103             ocd->ocd_connect_flags) {
1104                 CERROR("%s: Server didn't grant requested subset of flags: "
1105                        "asked=%#llx granted=%#llx\n",
1106                        imp->imp_obd->obd_name, imp->imp_connect_flags_orig,
1107                        ocd->ocd_connect_flags);
1108                 GOTO(out, rc = -EPROTO);
1109         }
1110
1111         if ((ocd->ocd_connect_flags2 & imp->imp_connect_flags2_orig) !=
1112             ocd->ocd_connect_flags2) {
1113                 CERROR("%s: Server didn't grant requested subset of flags2: "
1114                        "asked=%#llx granted=%#llx\n",
1115                        imp->imp_obd->obd_name, imp->imp_connect_flags2_orig,
1116                        ocd->ocd_connect_flags2);
1117                 GOTO(out, rc = -EPROTO);
1118         }
1119
1120         if (!(imp->imp_connect_flags_orig & OBD_CONNECT_LIGHTWEIGHT) &&
1121             (imp->imp_connect_flags_orig & OBD_CONNECT_MDS_MDS) &&
1122             (imp->imp_connect_flags_orig & OBD_CONNECT_FID) &&
1123             (ocd->ocd_connect_flags & OBD_CONNECT_VERSION)) {
1124                 __u32 major = OBD_OCD_VERSION_MAJOR(ocd->ocd_version);
1125                 __u32 minor = OBD_OCD_VERSION_MINOR(ocd->ocd_version);
1126                 __u32 patch = OBD_OCD_VERSION_PATCH(ocd->ocd_version);
1127
1128                 /* We do not support the MDT-MDT interoperations with
1129                  * different version MDT because of protocol changes. */
1130                 if (unlikely(major != LUSTRE_MAJOR ||
1131                              minor != LUSTRE_MINOR ||
1132                              abs(patch - LUSTRE_PATCH) > 3)) {
1133                         LCONSOLE_WARN("%s: import %p (%u.%u.%u.%u) tried the "
1134                                       "connection to different version MDT "
1135                                       "(%d.%d.%d.%d) %s\n",
1136                                       imp->imp_obd->obd_name, imp, LUSTRE_MAJOR,
1137                                       LUSTRE_MINOR, LUSTRE_PATCH, LUSTRE_FIX,
1138                                       major, minor, patch,
1139                                       OBD_OCD_VERSION_FIX(ocd->ocd_version),
1140                                       imp->imp_connection->c_remote_uuid.uuid);
1141
1142                         GOTO(out, rc = -EPROTO);
1143                 }
1144         }
1145
1146         old_connect_flags = exp_connect_flags(exp);
1147         exp->exp_connect_data = *ocd;
1148         imp->imp_obd->obd_self_export->exp_connect_data = *ocd;
1149
1150         /* The net statistics after (re-)connect is not valid anymore,
1151          * because may reflect other routing, etc.
1152          */
1153         service_timeout = lustre_msg_get_service_timeout(request->rq_repmsg);
1154         at_reinit(&imp->imp_at.iat_net_latency, 0, 0);
1155         ptlrpc_at_adj_net_latency(request, service_timeout);
1156
1157         /* Import flags should be updated before waking import at FULL state */
1158         rc = ptlrpc_connect_set_flags(imp, ocd, old_connect_flags, exp,
1159                                       aa->pcaa_initial_connect);
1160         class_export_put(exp);
1161         exp = NULL;
1162
1163         if (rc != 0)
1164                 GOTO(out, rc);
1165
1166         obd_import_event(imp->imp_obd, imp, IMP_EVENT_OCD);
1167
1168         if (aa->pcaa_initial_connect) {
1169                 spin_lock(&imp->imp_lock);
1170                 if (msg_flags & MSG_CONNECT_REPLAYABLE) {
1171                         imp->imp_replayable = 1;
1172                         CDEBUG(D_HA, "connected to replayable target: %s\n",
1173                                obd2cli_tgt(imp->imp_obd));
1174                 } else {
1175                         imp->imp_replayable = 0;
1176                 }
1177
1178                 /* if applies, adjust the imp->imp_msg_magic here
1179                  * according to reply flags
1180                  */
1181
1182                 imp->imp_remote_handle =
1183                         *lustre_msg_get_handle(request->rq_repmsg);
1184
1185                 /* Initial connects are allowed for clients with non-random
1186                  * uuids when servers are in recovery.  Simply signal the
1187                  * servers replay is complete and wait in REPLAY_WAIT.
1188                  */
1189                 if (msg_flags & MSG_CONNECT_RECOVERING) {
1190                         CDEBUG(D_HA, "connect to %s during recovery\n",
1191                                obd2cli_tgt(imp->imp_obd));
1192                         import_set_state_nolock(imp, LUSTRE_IMP_REPLAY_LOCKS);
1193                         spin_unlock(&imp->imp_lock);
1194                 } else {
1195                         spin_unlock(&imp->imp_lock);
1196                         ptlrpc_activate_import(imp, true);
1197                 }
1198
1199                 GOTO(finish, rc = 0);
1200         }
1201
1202         /* Determine what recovery state to move the import to. */
1203         if (MSG_CONNECT_RECONNECT & msg_flags) {
1204                 memset(&old_hdl, 0, sizeof(old_hdl));
1205                 if (!memcmp(&old_hdl, lustre_msg_get_handle(request->rq_repmsg),
1206                             sizeof(old_hdl))) {
1207                         LCONSOLE_WARN("Reconnect to %s (at @%s) failed due "
1208                                       "bad handle %#llx\n",
1209                                       obd2cli_tgt(imp->imp_obd),
1210                                       imp->imp_connection->c_remote_uuid.uuid,
1211                                       imp->imp_dlm_handle.cookie);
1212                         GOTO(out, rc = -ENOTCONN);
1213                 }
1214
1215                 if (memcmp(&imp->imp_remote_handle,
1216                            lustre_msg_get_handle(request->rq_repmsg),
1217                            sizeof(imp->imp_remote_handle))) {
1218                         int level = msg_flags & MSG_CONNECT_RECOVERING ?
1219                                 D_HA : D_WARNING;
1220
1221                         /* Bug 16611/14775: if server handle have changed,
1222                          * that means some sort of disconnection happened.
1223                          * If the server is not in recovery, that also means it
1224                          * already erased all of our state because of previous
1225                          * eviction. If it is in recovery - we are safe to
1226                          * participate since we can reestablish all of our state
1227                          * with server again
1228                          */
1229                         if ((MSG_CONNECT_RECOVERING & msg_flags)) {
1230                                 CDEBUG(level,
1231                                        "%s@%s changed server handle from "
1232                                        "%#llx to %#llx"
1233                                        " but is still in recovery\n",
1234                                        obd2cli_tgt(imp->imp_obd),
1235                                        imp->imp_connection->c_remote_uuid.uuid,
1236                                        imp->imp_remote_handle.cookie,
1237                                        lustre_msg_get_handle(
1238                                                request->rq_repmsg)->cookie);
1239                         } else {
1240                                 LCONSOLE_WARN("Evicted from %s (at %s) "
1241                                               "after server handle changed from "
1242                                               "%#llx to %#llx\n",
1243                                               obd2cli_tgt(imp->imp_obd),
1244                                               imp->imp_connection->
1245                                               c_remote_uuid.uuid,
1246                                               imp->imp_remote_handle.cookie,
1247                                               lustre_msg_get_handle(
1248                                                       request->rq_repmsg)->cookie);
1249                         }
1250
1251                         imp->imp_remote_handle =
1252                                 *lustre_msg_get_handle(request->rq_repmsg);
1253
1254                         if (!(MSG_CONNECT_RECOVERING & msg_flags)) {
1255                                 import_set_state(imp, LUSTRE_IMP_EVICTED);
1256                                 GOTO(finish, rc = 0);
1257                         }
1258                 } else {
1259                         CDEBUG(D_HA, "reconnected to %s@%s after partition\n",
1260                                obd2cli_tgt(imp->imp_obd),
1261                                imp->imp_connection->c_remote_uuid.uuid);
1262                 }
1263
1264                 if (imp->imp_invalid) {
1265                         CDEBUG(D_HA, "%s: reconnected but import is invalid; "
1266                                "marking evicted\n", imp->imp_obd->obd_name);
1267                         import_set_state(imp, LUSTRE_IMP_EVICTED);
1268                 } else if (MSG_CONNECT_RECOVERING & msg_flags) {
1269                         CDEBUG(D_HA, "%s: reconnected to %s during replay\n",
1270                                imp->imp_obd->obd_name,
1271                                obd2cli_tgt(imp->imp_obd));
1272
1273                         spin_lock(&imp->imp_lock);
1274                         imp->imp_resend_replay = 1;
1275                         spin_unlock(&imp->imp_lock);
1276
1277                         import_set_state(imp, imp->imp_replay_state);
1278                 } else {
1279                         import_set_state(imp, LUSTRE_IMP_RECOVER);
1280                 }
1281         } else if ((MSG_CONNECT_RECOVERING & msg_flags) && !imp->imp_invalid) {
1282                 LASSERT(imp->imp_replayable);
1283                 imp->imp_remote_handle =
1284                         *lustre_msg_get_handle(request->rq_repmsg);
1285                 imp->imp_last_replay_transno = 0;
1286                 imp->imp_replay_cursor = &imp->imp_committed_list;
1287                 import_set_state(imp, LUSTRE_IMP_REPLAY);
1288         } else if ((ocd->ocd_connect_flags & OBD_CONNECT_LIGHTWEIGHT) != 0 &&
1289                    !imp->imp_invalid) {
1290
1291                 obd_import_event(imp->imp_obd, imp, IMP_EVENT_INVALIDATE);
1292                 /* The below message is checked in recovery-small.sh test_106 */
1293                 DEBUG_REQ(D_HA, request, "%s: lwp recover",
1294                           imp->imp_obd->obd_name);
1295                 imp->imp_remote_handle =
1296                         *lustre_msg_get_handle(request->rq_repmsg);
1297                 import_set_state(imp, LUSTRE_IMP_RECOVER);
1298         } else {
1299                 DEBUG_REQ(D_HA, request,
1300                           "%s: evicting (reconnect/recover flags not set: %x)",
1301                           imp->imp_obd->obd_name, msg_flags);
1302                 imp->imp_remote_handle =
1303                         *lustre_msg_get_handle(request->rq_repmsg);
1304                 import_set_state(imp, LUSTRE_IMP_EVICTED);
1305         }
1306
1307         /* Sanity checks for a reconnected import. */
1308         if (!(imp->imp_replayable) != !(msg_flags & MSG_CONNECT_REPLAYABLE))
1309                 CERROR("imp_replayable flag does not match server after reconnect. We should LBUG right here.\n");
1310
1311         if (lustre_msg_get_last_committed(request->rq_repmsg) > 0 &&
1312             lustre_msg_get_last_committed(request->rq_repmsg) <
1313             aa->pcaa_peer_committed) {
1314                 static bool printed;
1315
1316                 /* The below message is checked in recovery-small.sh test_54 */
1317                 CERROR("%s: went back in time (transno %lld was previously committed, server now claims %lld)!\n",
1318                        obd2cli_tgt(imp->imp_obd), aa->pcaa_peer_committed,
1319                        lustre_msg_get_last_committed(request->rq_repmsg));
1320                 if (!printed) {
1321                         CERROR("For further information, see http://doc.lustre.org/lustre_manual.xhtml#went_back_in_time\n");
1322                         printed = true;
1323                 }
1324         }
1325
1326 finish:
1327         ptlrpc_prepare_replay(imp);
1328         rc = ptlrpc_import_recovery_state_machine(imp);
1329         if (rc == -ENOTCONN) {
1330                 CDEBUG(D_HA,
1331                        "evicted/aborted by %s@%s during recovery; invalidating and reconnecting\n",
1332                        obd2cli_tgt(imp->imp_obd),
1333                        imp->imp_connection->c_remote_uuid.uuid);
1334                 ptlrpc_connect_import(imp);
1335                 spin_lock(&imp->imp_lock);
1336                 imp->imp_connected = 0;
1337                 imp->imp_connect_tried = 1;
1338                 spin_unlock(&imp->imp_lock);
1339                 RETURN(0);
1340         }
1341
1342 out:
1343         if (exp != NULL)
1344                 class_export_put(exp);
1345
1346         spin_lock(&imp->imp_lock);
1347         imp->imp_connected = 0;
1348         imp->imp_connect_tried = 1;
1349
1350         if (rc != 0) {
1351                 bool inact = false;
1352
1353                 import_set_state_nolock(imp, LUSTRE_IMP_DISCON);
1354                 if (rc == -EACCES) {
1355                         /*
1356                          * Give up trying to reconnect
1357                          * EACCES means client has no permission for connection
1358                          */
1359                         imp->imp_obd->obd_no_recov = 1;
1360                         ptlrpc_deactivate_import_nolock(imp);
1361                         inact = true;
1362                 } else if (rc == -EPROTO) {
1363                         struct obd_connect_data *ocd;
1364
1365                         /* reply message might not be ready */
1366                         if (request->rq_repmsg == NULL) {
1367                                 spin_unlock(&imp->imp_lock);
1368                                 RETURN(-EPROTO);
1369                         }
1370
1371                         ocd = req_capsule_server_get(&request->rq_pill,
1372                                                      &RMF_CONNECT_DATA);
1373                         /* Servers are not supposed to refuse connections from
1374                          * clients based on version, only connection feature
1375                          * flags.  We should never see this from llite, but it
1376                          * may be useful for debugging in the future. */
1377                         if (ocd &&
1378                             (ocd->ocd_connect_flags & OBD_CONNECT_VERSION) &&
1379                             (ocd->ocd_version != LUSTRE_VERSION_CODE)) {
1380                                 LCONSOLE_ERROR_MSG(0x16a, "Server %s version "
1381                                                    "(%d.%d.%d.%d)"
1382                                                    " refused connection from this client "
1383                                                    "with an incompatible version (%s).  "
1384                                                    "Client must be recompiled\n",
1385                                                    obd2cli_tgt(imp->imp_obd),
1386                                                    OBD_OCD_VERSION_MAJOR(ocd->ocd_version),
1387                                                    OBD_OCD_VERSION_MINOR(ocd->ocd_version),
1388                                                    OBD_OCD_VERSION_PATCH(ocd->ocd_version),
1389                                                    OBD_OCD_VERSION_FIX(ocd->ocd_version),
1390                                                    LUSTRE_VERSION_STRING);
1391                                 ptlrpc_deactivate_import_nolock(imp);
1392                                 import_set_state_nolock(imp, LUSTRE_IMP_CLOSED);
1393                                 inact = true;
1394                         }
1395                 }
1396                 spin_unlock(&imp->imp_lock);
1397
1398                 if (inact)
1399                         obd_import_event(imp->imp_obd, imp, IMP_EVENT_INACTIVE);
1400
1401                 if (rc == -EPROTO)
1402                         RETURN(rc);
1403
1404                 ptlrpc_maybe_ping_import_soon(imp);
1405
1406                 CDEBUG(D_HA, "recovery of %s on %s failed (%d)\n",
1407                        obd2cli_tgt(imp->imp_obd),
1408                        (char *)imp->imp_connection->c_remote_uuid.uuid, rc);
1409         } else {
1410                 spin_unlock(&imp->imp_lock);
1411         }
1412
1413         wake_up(&imp->imp_recovery_waitq);
1414         RETURN(rc);
1415 }
1416
1417 /**
1418  * interpret callback for "completed replay" RPCs.
1419  * \see signal_completed_replay
1420  */
1421 static int completed_replay_interpret(const struct lu_env *env,
1422                                       struct ptlrpc_request *req,
1423                                       void *args, int rc)
1424 {
1425         ENTRY;
1426         atomic_dec(&req->rq_import->imp_replay_inflight);
1427         if (req->rq_status == 0 && !req->rq_import->imp_vbr_failed) {
1428                 ptlrpc_import_recovery_state_machine(req->rq_import);
1429         } else {
1430                 if (req->rq_import->imp_vbr_failed) {
1431                         CDEBUG(D_WARNING,
1432                                "%s: version recovery fails, reconnecting\n",
1433                                req->rq_import->imp_obd->obd_name);
1434                 } else {
1435                         CDEBUG(D_HA, "%s: LAST_REPLAY message error: %d, "
1436                                      "reconnecting\n",
1437                                req->rq_import->imp_obd->obd_name,
1438                                req->rq_status);
1439                 }
1440                 ptlrpc_connect_import(req->rq_import);
1441         }
1442
1443         RETURN(0);
1444 }
1445
1446 /**
1447  * Let server know that we have no requests to replay anymore.
1448  * Achieved by just sending a PING request
1449  */
1450 static int signal_completed_replay(struct obd_import *imp)
1451 {
1452         struct ptlrpc_request *req;
1453         ENTRY;
1454
1455         if (unlikely(OBD_FAIL_CHECK(OBD_FAIL_PTLRPC_FINISH_REPLAY)))
1456                 RETURN(0);
1457
1458         LASSERT(atomic_read(&imp->imp_replay_inflight) == 0);
1459         atomic_inc(&imp->imp_replay_inflight);
1460
1461         req = ptlrpc_request_alloc_pack(imp, &RQF_OBD_PING, LUSTRE_OBD_VERSION,
1462                                         OBD_PING);
1463         if (req == NULL) {
1464                 atomic_dec(&imp->imp_replay_inflight);
1465                 RETURN(-ENOMEM);
1466         }
1467
1468         ptlrpc_request_set_replen(req);
1469         req->rq_send_state = LUSTRE_IMP_REPLAY_WAIT;
1470         lustre_msg_add_flags(req->rq_reqmsg,
1471                              MSG_LOCK_REPLAY_DONE | MSG_REQ_REPLAY_DONE);
1472         if (AT_OFF)
1473                 req->rq_timeout *= 3;
1474         req->rq_interpret_reply = completed_replay_interpret;
1475
1476         ptlrpcd_add_req(req);
1477         RETURN(0);
1478 }
1479
1480 /**
1481  * In kernel code all import invalidation happens in its own
1482  * separate thread, so that whatever application happened to encounter
1483  * a problem could still be killed or otherwise continue
1484  */
1485 static int ptlrpc_invalidate_import_thread(void *data)
1486 {
1487         struct obd_import *imp = data;
1488
1489         ENTRY;
1490
1491         unshare_fs_struct();
1492
1493         CDEBUG(D_HA, "thread invalidate import %s to %s@%s\n",
1494                imp->imp_obd->obd_name, obd2cli_tgt(imp->imp_obd),
1495                imp->imp_connection->c_remote_uuid.uuid);
1496
1497         ptlrpc_invalidate_import(imp);
1498
1499         if (obd_dump_on_eviction) {
1500                 CERROR("dump the log upon eviction\n");
1501                 libcfs_debug_dumplog();
1502         }
1503
1504         import_set_state(imp, LUSTRE_IMP_RECOVER);
1505         ptlrpc_import_recovery_state_machine(imp);
1506
1507         class_import_put(imp);
1508         RETURN(0);
1509 }
1510
1511 /**
1512  * This is the state machine for client-side recovery on import.
1513  *
1514  * Typicaly we have two possibly paths. If we came to server and it is not
1515  * in recovery, we just enter IMP_EVICTED state, invalidate our import
1516  * state and reconnect from scratch.
1517  * If we came to server that is in recovery, we enter IMP_REPLAY import state.
1518  * We go through our list of requests to replay and send them to server one by
1519  * one.
1520  * After sending all request from the list we change import state to
1521  * IMP_REPLAY_LOCKS and re-request all the locks we believe we have from server
1522  * and also all the locks we don't yet have and wait for server to grant us.
1523  * After that we send a special "replay completed" request and change import
1524  * state to IMP_REPLAY_WAIT.
1525  * Upon receiving reply to that "replay completed" RPC we enter IMP_RECOVER
1526  * state and resend all requests from sending list.
1527  * After that we promote import to FULL state and send all delayed requests
1528  * and import is fully operational after that.
1529  *
1530  */
1531 int ptlrpc_import_recovery_state_machine(struct obd_import *imp)
1532 {
1533         int rc = 0;
1534         int inflight;
1535         char *target_start;
1536         int target_len;
1537
1538         ENTRY;
1539         if (imp->imp_state == LUSTRE_IMP_EVICTED) {
1540                 deuuidify(obd2cli_tgt(imp->imp_obd), NULL,
1541                           &target_start, &target_len);
1542                 /* Don't care about MGC eviction */
1543                 if (strcmp(imp->imp_obd->obd_type->typ_name,
1544                            LUSTRE_MGC_NAME) != 0) {
1545                         LCONSOLE_ERROR_MSG(0x167, "%s: This client was evicted "
1546                                            "by %.*s; in progress operations "
1547                                            "using this service will fail.\n",
1548                                            imp->imp_obd->obd_name, target_len,
1549                                            target_start);
1550                         LASSERTF(!obd_lbug_on_eviction, "LBUG upon eviction\n");
1551                 }
1552                 CDEBUG(D_HA, "evicted from %s@%s; invalidating\n",
1553                        obd2cli_tgt(imp->imp_obd),
1554                        imp->imp_connection->c_remote_uuid.uuid);
1555                 /* reset vbr_failed flag upon eviction */
1556                 spin_lock(&imp->imp_lock);
1557                 imp->imp_vbr_failed = 0;
1558                 spin_unlock(&imp->imp_lock);
1559
1560                 {
1561                 struct task_struct *task;
1562                 /* bug 17802:  XXX client_disconnect_export vs connect request
1563                  * race. if client is evicted at this time then we start
1564                  * invalidate thread without reference to import and import can
1565                  * be freed at same time. */
1566                 class_import_get(imp);
1567                 task = kthread_run(ptlrpc_invalidate_import_thread, imp,
1568                                      "ll_imp_inval");
1569                 if (IS_ERR(task)) {
1570                         class_import_put(imp);
1571                         CERROR("error starting invalidate thread: %d\n", rc);
1572                         rc = PTR_ERR(task);
1573                 } else {
1574                         rc = 0;
1575                 }
1576                 RETURN(rc);
1577                 }
1578         }
1579
1580         if (imp->imp_state == LUSTRE_IMP_REPLAY) {
1581                 CDEBUG(D_HA, "replay requested by %s\n",
1582                        obd2cli_tgt(imp->imp_obd));
1583                 rc = ptlrpc_replay_next(imp, &inflight);
1584                 if (inflight == 0 &&
1585                     atomic_read(&imp->imp_replay_inflight) == 0) {
1586                         import_set_state(imp, LUSTRE_IMP_REPLAY_LOCKS);
1587                         rc = ldlm_replay_locks(imp);
1588                         if (rc)
1589                                 GOTO(out, rc);
1590                 }
1591                 rc = 0;
1592         }
1593
1594         if (imp->imp_state == LUSTRE_IMP_REPLAY_LOCKS) {
1595                 if (atomic_read(&imp->imp_replay_inflight) == 0) {
1596                         import_set_state(imp, LUSTRE_IMP_REPLAY_WAIT);
1597                         rc = signal_completed_replay(imp);
1598                         if (rc)
1599                                 GOTO(out, rc);
1600                 }
1601         }
1602
1603         if (imp->imp_state == LUSTRE_IMP_REPLAY_WAIT) {
1604                 if (atomic_read(&imp->imp_replay_inflight) == 0) {
1605                         import_set_state(imp, LUSTRE_IMP_RECOVER);
1606                 }
1607         }
1608
1609         if (imp->imp_state == LUSTRE_IMP_RECOVER) {
1610                 struct ptlrpc_connection *conn = imp->imp_connection;
1611
1612                 rc = ptlrpc_resend(imp);
1613                 if (rc)
1614                         GOTO(out, rc);
1615                 ptlrpc_activate_import(imp, true);
1616
1617                 CDEBUG_LIMIT(imp->imp_was_idle ?
1618                                 imp->imp_idle_debug : D_CONSOLE,
1619                              "%s: Connection restored to %s (at %s)\n",
1620                              imp->imp_obd->obd_name,
1621                              obd_uuid2str(&conn->c_remote_uuid),
1622                              obd_import_nid2str(imp));
1623                 spin_lock(&imp->imp_lock);
1624                 imp->imp_was_idle = 0;
1625                 spin_unlock(&imp->imp_lock);
1626         }
1627
1628         if (imp->imp_state == LUSTRE_IMP_FULL) {
1629                 wake_up(&imp->imp_recovery_waitq);
1630                 ptlrpc_wake_delayed(imp);
1631         }
1632
1633 out:
1634         RETURN(rc);
1635 }
1636
1637 static struct ptlrpc_request *ptlrpc_disconnect_prep_req(struct obd_import *imp)
1638 {
1639         struct ptlrpc_request *req;
1640         int rq_opc, rc = 0;
1641         ENTRY;
1642
1643         switch (imp->imp_connect_op) {
1644         case OST_CONNECT:
1645                 rq_opc = OST_DISCONNECT;
1646                 break;
1647         case MDS_CONNECT:
1648                 rq_opc = MDS_DISCONNECT;
1649                 break;
1650         case MGS_CONNECT:
1651                 rq_opc = MGS_DISCONNECT;
1652                 break;
1653         default:
1654                 rc = -EINVAL;
1655                 CERROR("%s: don't know how to disconnect from %s "
1656                        "(connect_op %d): rc = %d\n",
1657                        imp->imp_obd->obd_name, obd2cli_tgt(imp->imp_obd),
1658                        imp->imp_connect_op, rc);
1659                 RETURN(ERR_PTR(rc));
1660         }
1661
1662         req = ptlrpc_request_alloc_pack(imp, &RQF_MDS_DISCONNECT,
1663                                         LUSTRE_OBD_VERSION, rq_opc);
1664         if (req == NULL)
1665                 RETURN(ERR_PTR(-ENOMEM));
1666
1667         /* We are disconnecting, do not retry a failed DISCONNECT rpc if
1668          * it fails.  We can get through the above with a down server
1669          * if the client doesn't know the server is gone yet. */
1670         req->rq_no_resend = 1;
1671
1672         /* We want client umounts to happen quickly, no matter the
1673            server state... */
1674         req->rq_timeout = min_t(timeout_t, req->rq_timeout,
1675                                 INITIAL_CONNECT_TIMEOUT);
1676
1677         import_set_state(imp, LUSTRE_IMP_CONNECTING);
1678         req->rq_send_state =  LUSTRE_IMP_CONNECTING;
1679         ptlrpc_request_set_replen(req);
1680
1681         RETURN(req);
1682 }
1683
1684 int ptlrpc_disconnect_import(struct obd_import *imp, int noclose)
1685 {
1686         struct ptlrpc_request *req;
1687         int rc = 0;
1688         ENTRY;
1689
1690         if (imp->imp_obd->obd_force)
1691                 GOTO(set_state, rc);
1692
1693         /* probably the import has been disconnected already being idle */
1694         spin_lock(&imp->imp_lock);
1695         if (imp->imp_state == LUSTRE_IMP_IDLE)
1696                 GOTO(out, rc);
1697         spin_unlock(&imp->imp_lock);
1698
1699         if (ptlrpc_import_in_recovery(imp)) {
1700                 long timeout_jiffies;
1701                 time64_t timeout;
1702
1703                 if (AT_OFF) {
1704                         if (imp->imp_server_timeout)
1705                                 timeout = obd_timeout >> 1;
1706                         else
1707                                 timeout = obd_timeout;
1708                 } else {
1709                         u32 req_portal;
1710                         int idx;
1711
1712                         req_portal = imp->imp_client->cli_request_portal;
1713                         idx = import_at_get_index(imp, req_portal);
1714                         timeout = at_get(&imp->imp_at.iat_service_estimate[idx]);
1715                 }
1716
1717                 timeout_jiffies = cfs_time_seconds(timeout);
1718                 if (wait_event_idle_timeout(imp->imp_recovery_waitq,
1719                                             !ptlrpc_import_in_recovery(imp),
1720                                             timeout_jiffies) == 0 &&
1721                     l_wait_event_abortable(imp->imp_recovery_waitq,
1722                                            !ptlrpc_import_in_recovery(imp)) < 0)
1723                         rc = -EINTR;
1724         }
1725
1726         spin_lock(&imp->imp_lock);
1727         if (imp->imp_state != LUSTRE_IMP_FULL)
1728                 GOTO(out, rc);
1729         spin_unlock(&imp->imp_lock);
1730
1731         req = ptlrpc_disconnect_prep_req(imp);
1732         if (IS_ERR(req))
1733                 GOTO(set_state, rc = PTR_ERR(req));
1734         rc = ptlrpc_queue_wait(req);
1735         ptlrpc_req_finished(req);
1736
1737 set_state:
1738         spin_lock(&imp->imp_lock);
1739 out:
1740         if (noclose)
1741                 import_set_state_nolock(imp, LUSTRE_IMP_DISCON);
1742         else
1743                 import_set_state_nolock(imp, LUSTRE_IMP_CLOSED);
1744         memset(&imp->imp_remote_handle, 0, sizeof(imp->imp_remote_handle));
1745         spin_unlock(&imp->imp_lock);
1746
1747         if (rc == -ETIMEDOUT || rc == -ENOTCONN || rc == -ESHUTDOWN)
1748                 rc = 0;
1749         RETURN(rc);
1750 }
1751 EXPORT_SYMBOL(ptlrpc_disconnect_import);
1752
1753 static void ptlrpc_reset_reqs_generation(struct obd_import *imp)
1754 {
1755         struct ptlrpc_request *old, *tmp;
1756
1757         /* tag all resendable requests generated before disconnection
1758          * notice this code is part of disconnect-at-idle path only */
1759         list_for_each_entry_safe(old, tmp, &imp->imp_delayed_list,
1760                         rq_list) {
1761                 spin_lock(&old->rq_lock);
1762                 if (old->rq_import_generation == imp->imp_generation - 1 &&
1763                     ((imp->imp_initiated_at == imp->imp_generation) ||
1764                      !old->rq_no_resend))
1765                         old->rq_import_generation = imp->imp_generation;
1766                 spin_unlock(&old->rq_lock);
1767         }
1768 }
1769
1770 static int ptlrpc_disconnect_idle_interpret(const struct lu_env *env,
1771                                             struct ptlrpc_request *req,
1772                                             void *args, int rc)
1773 {
1774         struct obd_import *imp = req->rq_import;
1775         int connect = 0;
1776
1777         DEBUG_REQ(D_HA, req, "inflight=%d, refcount=%d: rc = %d",
1778                   atomic_read(&imp->imp_inflight),
1779                   refcount_read(&imp->imp_refcount), rc);
1780
1781         spin_lock(&imp->imp_lock);
1782         /* DISCONNECT reply can be late and another connection can just
1783          * be initiated. so we have to abort disconnection. */
1784         if (req->rq_import_generation == imp->imp_generation &&
1785             imp->imp_state != LUSTRE_IMP_CLOSED) {
1786                 LASSERTF(imp->imp_state == LUSTRE_IMP_CONNECTING,
1787                          "%s\n", ptlrpc_import_state_name(imp->imp_state));
1788                 memset(&imp->imp_remote_handle, 0,
1789                        sizeof(imp->imp_remote_handle));
1790                 /* take our DISCONNECT into account */
1791                 if (atomic_read(&imp->imp_reqs) > 1) {
1792                         imp->imp_generation++;
1793                         imp->imp_initiated_at = imp->imp_generation;
1794                         import_set_state_nolock(imp, LUSTRE_IMP_NEW);
1795                         ptlrpc_reset_reqs_generation(imp);
1796                         connect = 1;
1797                 } else {
1798                         /* do not expose transient IDLE state */
1799                         import_set_state_nolock(imp, LUSTRE_IMP_IDLE);
1800                 }
1801         }
1802
1803         if (connect) {
1804                 rc = ptlrpc_connect_import_locked(imp);
1805                 if (rc >= 0)
1806                         ptlrpc_pinger_add_import(imp);
1807         } else {
1808                 spin_unlock(&imp->imp_lock);
1809         }
1810
1811         return 0;
1812 }
1813
1814 int ptlrpc_disconnect_and_idle_import(struct obd_import *imp)
1815 {
1816         struct ptlrpc_request *req;
1817         ENTRY;
1818
1819         if (imp->imp_obd->obd_force)
1820                 RETURN(0);
1821
1822         if (ptlrpc_import_in_recovery(imp))
1823                 RETURN(0);
1824
1825         spin_lock(&imp->imp_lock);
1826         if (imp->imp_state != LUSTRE_IMP_FULL) {
1827                 spin_unlock(&imp->imp_lock);
1828                 RETURN(0);
1829         }
1830         spin_unlock(&imp->imp_lock);
1831
1832         req = ptlrpc_disconnect_prep_req(imp);
1833         if (IS_ERR(req))
1834                 RETURN(PTR_ERR(req));
1835
1836         CDEBUG_LIMIT(imp->imp_idle_debug, "%s: disconnect after %llus idle\n",
1837                      imp->imp_obd->obd_name,
1838                      ktime_get_real_seconds() - imp->imp_last_reply_time);
1839
1840         /* don't make noise at reconnection */
1841         spin_lock(&imp->imp_lock);
1842         imp->imp_was_idle = 1;
1843         spin_unlock(&imp->imp_lock);
1844
1845         req->rq_interpret_reply = ptlrpc_disconnect_idle_interpret;
1846         ptlrpcd_add_req(req);
1847
1848         RETURN(0);
1849 }
1850 EXPORT_SYMBOL(ptlrpc_disconnect_and_idle_import);
1851
1852 void ptlrpc_cleanup_imp(struct obd_import *imp)
1853 {
1854         ENTRY;
1855
1856         spin_lock(&imp->imp_lock);
1857
1858         import_set_state_nolock(imp, LUSTRE_IMP_CLOSED);
1859         imp->imp_generation++;
1860         ptlrpc_abort_inflight(imp);
1861
1862         spin_unlock(&imp->imp_lock);
1863
1864         EXIT;
1865 }
1866
1867 /* Adaptive Timeout utils */
1868
1869 /* Update at_current_timeout with the specified value (bounded by at_min and
1870  * at_max), as well as the AT history "bins".
1871  *  - Bin into timeslices using AT_BINS bins.
1872  *  - This gives us a max of the last at_history seconds without the storage,
1873  *    but still smoothing out a return to normalcy from a slow response.
1874  *  - (E.g. remember the maximum latency in each minute of the last 4 minutes.)
1875  */
1876 timeout_t at_measured(struct adaptive_timeout *at, timeout_t timeout)
1877 {
1878         timeout_t old_timeout = at->at_current_timeout;
1879         time64_t now = ktime_get_real_seconds();
1880         long binlimit = max_t(long, at_history / AT_BINS, 1);
1881
1882         LASSERT(at);
1883         CDEBUG(D_OTHER, "add %u to %p time=%lld v=%u (%u %u %u %u)\n",
1884                timeout, at, now - at->at_binstart, at->at_current_timeout,
1885                at->at_hist[0], at->at_hist[1], at->at_hist[2], at->at_hist[3]);
1886
1887         if (timeout <= 0)
1888                 /* Negative timeouts and 0's don't count, because we never
1889                  * want our timeout to drop to 0 or below, and because 0 could
1890                  * mean an error
1891                  */
1892                 return 0;
1893
1894         spin_lock(&at->at_lock);
1895
1896         if (unlikely(at->at_binstart == 0)) {
1897                 /* Special case to remove default from history */
1898                 at->at_current_timeout = timeout;
1899                 at->at_worst_timeout_ever = timeout;
1900                 at->at_worst_timestamp = now;
1901                 at->at_hist[0] = timeout;
1902                 at->at_binstart = now;
1903         } else if (now - at->at_binstart < binlimit ) {
1904                 /* in bin 0 */
1905                 at->at_hist[0] = max_t(timeout_t, timeout, at->at_hist[0]);
1906                 at->at_current_timeout = max_t(timeout_t, timeout,
1907                                                at->at_current_timeout);
1908         } else {
1909                 int i, shift;
1910                 timeout_t maxv = timeout;
1911
1912                 /* move bins over */
1913                 shift = (u32)(now - at->at_binstart) / binlimit;
1914                 LASSERT(shift > 0);
1915                 for(i = AT_BINS - 1; i >= 0; i--) {
1916                         if (i >= shift) {
1917                                 at->at_hist[i] = at->at_hist[i - shift];
1918                                 maxv = max_t(timeout_t, maxv, at->at_hist[i]);
1919                         } else {
1920                                 at->at_hist[i] = 0;
1921                         }
1922                 }
1923                 at->at_hist[0] = timeout;
1924                 at->at_current_timeout = maxv;
1925                 at->at_binstart += shift * binlimit;
1926         }
1927
1928         if (at->at_current_timeout > at->at_worst_timeout_ever) {
1929                 at->at_worst_timeout_ever = at->at_current_timeout;
1930                 at->at_worst_timestamp = now;
1931         }
1932
1933         if (at->at_flags & AT_FLG_NOHIST)
1934                 /* Only keep last reported val; keeping the rest of the history
1935                  * for debugfs only
1936                  */
1937                 at->at_current_timeout = timeout;
1938
1939         if (at_max > 0)
1940                 at->at_current_timeout = min_t(timeout_t,
1941                                                at->at_current_timeout, at_max);
1942         at->at_current_timeout = max_t(timeout_t, at->at_current_timeout,
1943                                        at_min);
1944         if (at->at_current_timeout != old_timeout)
1945                 CDEBUG(D_OTHER,
1946                        "AT %p change: old=%u new=%u delta=%d (val=%d) hist %u %u %u %u\n",
1947                        at, old_timeout, at->at_current_timeout,
1948                        at->at_current_timeout - old_timeout, timeout,
1949                        at->at_hist[0], at->at_hist[1], at->at_hist[2],
1950                        at->at_hist[3]);
1951
1952         /* if we changed, report the old timeout value */
1953         old_timeout = (at->at_current_timeout != old_timeout) ? old_timeout : 0;
1954
1955         spin_unlock(&at->at_lock);
1956         return old_timeout;
1957 }
1958
1959 /* Find the imp_at index for a given portal; assign if space available */
1960 int import_at_get_index(struct obd_import *imp, int portal)
1961 {
1962         struct imp_at *at = &imp->imp_at;
1963         int i;
1964
1965         for (i = 0; i < IMP_AT_MAX_PORTALS; i++) {
1966                 if (at->iat_portal[i] == portal)
1967                         return i;
1968                 if (at->iat_portal[i] == 0)
1969                         /* unused */
1970                         break;
1971         }
1972
1973         /* Not found in list, add it under a lock */
1974         spin_lock(&imp->imp_lock);
1975
1976         /* Check unused under lock */
1977         for (; i < IMP_AT_MAX_PORTALS; i++) {
1978                 if (at->iat_portal[i] == portal)
1979                         goto out;
1980                 if (at->iat_portal[i] == 0)
1981                         /* unused */
1982                         break;
1983         }
1984
1985         /* Not enough portals? */
1986         LASSERT(i < IMP_AT_MAX_PORTALS);
1987
1988         at->iat_portal[i] = portal;
1989 out:
1990         spin_unlock(&imp->imp_lock);
1991         return i;
1992 }