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