lustre/ptlrpc/import.c

   1 /* -*- mode: c; c-basic-offset: 8; indent-tabs-mode: nil; -*-
   2  * vim:expandtab:shiftwidth=8:tabstop=8:
   3  *
   4  *  Copyright (c) 2002, 2003 Cluster File Systems, Inc.
   5  *   Author: Mike Shaver <shaver@clusterfs.com>
   6  *
   7  *   This file is part of Lustre, http://www.lustre.org.
   8  *
   9  *   Lustre is free software; you can redistribute it and/or
  10  *   modify it under the terms of version 2 of the GNU General Public
  11  *   License as published by the Free Software Foundation.
  12  *
  13  *   Lustre is distributed in the hope that it will be useful,
  14  *   but WITHOUT ANY WARRANTY; without even the implied warranty of
  15  *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  16  *   GNU General Public License for more details.
  17  *
  18  *   You should have received a copy of the GNU General Public License
  19  *   along with Lustre; if not, write to the Free Software
  20  *   Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
  21  */
  22
  23 #define DEBUG_SUBSYSTEM S_RPC
  24 #ifdef __KERNEL__
  25 # include <linux/config.h>
  26 # include <linux/module.h>
  27 # include <linux/kmod.h>
  28 #else
  29 # include <liblustre.h>
  30 #endif
  31
  32 #include <linux/obd_support.h>
  33 #include <linux/lustre_ha.h>
  34 #include <linux/lustre_net.h>
  35 #include <linux/lustre_import.h>
  36 #include <linux/lustre_export.h>
  37 #include <linux/obd.h>
  38 #include <linux/obd_class.h>
  39
  40 #include "ptlrpc_internal.h"
  41
  42 struct ptlrpc_connect_async_args {
  43          __u64 pcaa_peer_committed;
  44         int pcaa_initial_connect;
  45 };
  46
  47 /* A CLOSED import should remain so. */
  48 #define IMPORT_SET_STATE_NOLOCK(imp, state)                                    \
  49 do {                                                                           \
  50         if (imp->imp_state != LUSTRE_IMP_CLOSED) {                             \
  51                CDEBUG(D_HA, "%p %s: changing import state from %s to %s\n",    \
  52                       imp, imp->imp_target_uuid.uuid,                          \
  53                       ptlrpc_import_state_name(imp->imp_state),                \
  54                       ptlrpc_import_state_name(state));                        \
  55                imp->imp_state = state;                                         \
  56         }                                                                      \
  57 } while(0)
  58
  59 #define IMPORT_SET_STATE(imp, state)                    \
  60 do {                                                    \
  61         unsigned long flags;                            \
  62                                                         \
  63         spin_lock_irqsave(&imp->imp_lock, flags);       \
  64         IMPORT_SET_STATE_NOLOCK(imp, state);            \
  65         spin_unlock_irqrestore(&imp->imp_lock, flags);  \
  66 } while(0)
  67
  68
  69 static int ptlrpc_connect_interpret(struct ptlrpc_request *request,
  70                                     void * data, int rc);
  71 int ptlrpc_import_recovery_state_machine(struct obd_import *imp);
  72
  73 /* Only this function is allowed to change the import state when it is
  74  * CLOSED. I would rather refcount the import and free it after
  75  * disconnection like we do with exports. To do that, the client_obd
  76  * will need to save the peer info somewhere other than in the import,
  77  * though. */
  78 int ptlrpc_init_import(struct obd_import *imp)
  79 {
  80         unsigned long flags;
  81
  82         spin_lock_irqsave(&imp->imp_lock, flags);
  83
  84         imp->imp_generation++;
  85         imp->imp_state =  LUSTRE_IMP_NEW;
  86
  87         spin_unlock_irqrestore(&imp->imp_lock, flags);
  88
  89         return 0;
  90 }
  91
  92 /* Returns true if import was FULL, false if import was already not
  93  * connected.
  94  */
  95 int ptlrpc_set_import_discon(struct obd_import *imp)
  96 {
  97         unsigned long flags;
  98         int rc = 0;
  99
 100         spin_lock_irqsave(&imp->imp_lock, flags);
 101
 102         if (imp->imp_state == LUSTRE_IMP_FULL) {
 103                 IMPORT_SET_STATE_NOLOCK(imp, LUSTRE_IMP_DISCON);
 104                 spin_unlock_irqrestore(&imp->imp_lock, flags);
 105                 obd_import_event(imp->imp_obd, imp, IMP_EVENT_DISCON);
 106                 rc = 1;
 107         } else {
 108                 spin_unlock_irqrestore(&imp->imp_lock, flags);
 109                 CDEBUG(D_HA, "%p %s: import already not connected: %s\n",
 110                        imp,imp->imp_client->cli_name,
 111                        ptlrpc_import_state_name(imp->imp_state));
 112         }
 113
 114         return rc;
 115 }
 116
 117 /*
 118  * This acts as a barrier; all existing requests are rejected, and
 119  * no new requests will be accepted until the import is valid again.
 120  */
 121 void ptlrpc_deactivate_import(struct obd_import *imp)
 122 {
 123         unsigned long flags;
 124         ENTRY;
 125
 126         spin_lock_irqsave(&imp->imp_lock, flags);
 127         CDEBUG(D_HA, "setting import %s INVALID\n",
 128                imp->imp_target_uuid.uuid);
 129         imp->imp_invalid = 1;
 130         imp->imp_generation++;
 131         spin_unlock_irqrestore(&imp->imp_lock, flags);
 132
 133         ptlrpc_abort_inflight(imp);
 134         obd_import_event(imp->imp_obd, imp, IMP_EVENT_INACTIVE);
 135 }
 136
 137 /*
 138  * This function will invalidate the import, if necessary, then block
 139  * for all the RPC completions, and finally notify the obd to
 140  * invalidate its state (ie cancel locks, clear pending requests,
 141  * etc).
 142  *
 143  * in_rpc: true if this is called while processing an rpc, like
 144  *    CONNECT. It will allow for one RPC to be inflight while
 145  *    waiting for requests to complete. Ugly, yes, but I don't see an
 146  *    cleaner way right now.
 147  */
 148 void ptlrpc_invalidate_import(struct obd_import *imp, int in_rpc)
 149 {
 150         struct l_wait_info lwi;
 151         int inflight = 0;
 152         int rc;
 153
 154         if (!imp->imp_invalid)
 155                 ptlrpc_deactivate_import(imp);
 156
 157         LASSERT(imp->imp_invalid);
 158
 159         if (in_rpc)
 160                 inflight = 1;
 161         /* wait for all requests to error out and call completion callbacks */
 162         lwi = LWI_TIMEOUT_INTR(MAX(obd_timeout * HZ, 1), NULL,
 163                                NULL, NULL);
 164         rc = l_wait_event(imp->imp_recovery_waitq,
 165                           (atomic_read(&imp->imp_inflight) == inflight),
 166                           &lwi);
 167
 168         if (rc)
 169                 CERROR("%s: rc = %d waiting for callback (%d != %d)\n",
 170                        imp->imp_target_uuid.uuid, rc,
 171                        atomic_read(&imp->imp_inflight), inflight);
 172
 173         obd_import_event(imp->imp_obd, imp, IMP_EVENT_INVALIDATE);
 174 }
 175
 176 static void ptlrpc_activate_import(struct obd_import *imp)
 177 {
 178         struct obd_device *obd = imp->imp_obd;
 179         unsigned long flags;
 180
 181         spin_lock_irqsave(&imp->imp_lock, flags);
 182         imp->imp_invalid = 0;
 183         spin_unlock_irqrestore(&imp->imp_lock, flags);
 184
 185         obd_import_event(obd, imp, IMP_EVENT_ACTIVE);
 186 }
 187
 188 void ptlrpc_fail_import(struct obd_import *imp, int generation)
 189 {
 190         ENTRY;
 191
 192         LASSERT (!imp->imp_dlm_fake);
 193
 194         if (ptlrpc_set_import_discon(imp)) {
 195                 unsigned long flags;
 196
 197                 if (!imp->imp_replayable) {
 198                         CDEBUG(D_HA, "import %s@%s for %s not replayable, "
 199                                "auto-deactivating\n",
 200                                imp->imp_target_uuid.uuid,
 201                                imp->imp_connection->c_remote_uuid.uuid,
 202                                imp->imp_obd->obd_name);
 203                         ptlrpc_deactivate_import(imp);
 204                 }
 205
 206                 CDEBUG(D_HA, "%s: waking up pinger\n",
 207                        imp->imp_target_uuid.uuid);
 208
 209                 spin_lock_irqsave(&imp->imp_lock, flags);
 210                 imp->imp_force_verify = 1;
 211                 spin_unlock_irqrestore(&imp->imp_lock, flags);
 212
 213                 ptlrpc_pinger_wake_up();
 214         }
 215         EXIT;
 216 }
 217
 218 int ptlrpc_connect_import(struct obd_import *imp, char * new_uuid)
 219 {
 220         struct obd_device *obd = imp->imp_obd;
 221         int initial_connect = 0;
 222         int rc;
 223         __u64 committed_before_reconnect = 0;
 224         struct ptlrpc_request *request;
 225         int size[] = {sizeof(imp->imp_target_uuid),
 226                                  sizeof(obd->obd_uuid),
 227                                  sizeof(imp->imp_dlm_handle)};
 228         char *tmp[] = {imp->imp_target_uuid.uuid,
 229                        obd->obd_uuid.uuid,
 230                        (char *)&imp->imp_dlm_handle};
 231         struct ptlrpc_connect_async_args *aa;
 232         unsigned long flags;
 233
 234         spin_lock_irqsave(&imp->imp_lock, flags);
 235         if (imp->imp_state == LUSTRE_IMP_CLOSED) {
 236                 spin_unlock_irqrestore(&imp->imp_lock, flags);
 237                 CERROR("can't connect to a closed import\n");
 238                 RETURN(-EINVAL);
 239         } else if (imp->imp_state == LUSTRE_IMP_FULL) {
 240                 spin_unlock_irqrestore(&imp->imp_lock, flags);
 241                 CERROR("already connected\n");
 242                 RETURN(0);
 243         } else if (imp->imp_state == LUSTRE_IMP_CONNECTING) {
 244                 spin_unlock_irqrestore(&imp->imp_lock, flags);
 245                 CERROR("already connecting\n");
 246                 RETURN(-EALREADY);
 247         }
 248
 249         IMPORT_SET_STATE_NOLOCK(imp, LUSTRE_IMP_CONNECTING);
 250
 251         imp->imp_conn_cnt++;
 252         imp->imp_last_replay_transno = 0;
 253
 254         if (imp->imp_remote_handle.cookie == 0) {
 255                 initial_connect = 1;
 256         } else {
 257                 committed_before_reconnect = imp->imp_peer_committed_transno;;
 258
 259         }
 260
 261
 262         spin_unlock_irqrestore(&imp->imp_lock, flags);
 263
 264         if (new_uuid) {
 265                 struct ptlrpc_connection *conn;
 266                 struct obd_uuid uuid;
 267                 struct obd_export *dlmexp;
 268
 269                 obd_str2uuid(&uuid, new_uuid);
 270
 271                 conn = ptlrpc_uuid_to_connection(&uuid);
 272                 if (!conn)
 273                         GOTO(out, rc = -ENOENT);
 274
 275                 CDEBUG(D_HA, "switching import %s/%s from %s to %s\n",
 276                        imp->imp_target_uuid.uuid, imp->imp_obd->obd_name,
 277                        imp->imp_connection->c_remote_uuid.uuid,
 278                        conn->c_remote_uuid.uuid);
 279
 280                 /* Switch the import's connection and the DLM export's
 281                  * connection (which are almost certainly the same, but we
 282                  * keep distinct refs just to make things clearer. I think. */
 283                 if (imp->imp_connection)
 284                         ptlrpc_put_connection(imp->imp_connection);
 285                 /* We hand off the ref from ptlrpc_get_connection. */
 286                 imp->imp_connection = conn;
 287
 288                 dlmexp = class_conn2export(&imp->imp_dlm_handle);
 289
 290                 LASSERT(dlmexp != NULL);
 291
 292                 if (dlmexp->exp_connection)
 293                         ptlrpc_put_connection(dlmexp->exp_connection);
 294                 dlmexp->exp_connection = ptlrpc_connection_addref(conn);
 295                 class_export_put(dlmexp);
 296
 297         }
 298
 299         request = ptlrpc_prep_req(imp, imp->imp_connect_op, 3, size, tmp);
 300         if (!request)
 301                 GOTO(out, rc = -ENOMEM);
 302
 303 #ifndef __KERNEL__
 304         lustre_msg_add_op_flags(request->rq_reqmsg, MSG_CONNECT_LIBCLIENT);
 305 #endif
 306
 307         request->rq_send_state = LUSTRE_IMP_CONNECTING;
 308         request->rq_replen = lustre_msg_size(0, NULL);
 309         request->rq_interpret_reply = ptlrpc_connect_interpret;
 310
 311         LASSERT (sizeof (*aa) <= sizeof (request->rq_async_args));
 312         aa = (struct ptlrpc_connect_async_args *)&request->rq_async_args;
 313         memset(aa, 0, sizeof *aa);
 314
 315         aa->pcaa_peer_committed = committed_before_reconnect;
 316         aa->pcaa_initial_connect = initial_connect;
 317
 318         if (aa->pcaa_initial_connect)
 319                 imp->imp_replayable = 1;
 320
 321         ptlrpcd_add_req(request);
 322         rc = 0;
 323 out:
 324         if (rc != 0) {
 325                 IMPORT_SET_STATE(imp, LUSTRE_IMP_DISCON);
 326         }
 327
 328         RETURN(rc);
 329 }
 330
 331 static int ptlrpc_connect_interpret(struct ptlrpc_request *request,
 332                                     void * data, int rc)
 333 {
 334         struct ptlrpc_connect_async_args *aa = data;
 335         struct obd_import *imp = request->rq_import;
 336         struct lustre_handle old_hdl;
 337         unsigned long flags;
 338         int msg_flags;
 339         ENTRY;
 340
 341         spin_lock_irqsave(&imp->imp_lock, flags);
 342         if (imp->imp_state == LUSTRE_IMP_CLOSED) {
 343                 spin_unlock_irqrestore(&imp->imp_lock, flags);
 344                 RETURN(0);
 345         }
 346         spin_unlock_irqrestore(&imp->imp_lock, flags);
 347
 348         if (rc)
 349                 GOTO(out, rc);
 350
 351         msg_flags = lustre_msg_get_op_flags(request->rq_repmsg);
 352
 353         if (aa->pcaa_initial_connect) {
 354                 if (msg_flags & MSG_CONNECT_REPLAYABLE) {
 355                         CDEBUG(D_HA, "connected to replayable target: %s\n",
 356                                imp->imp_target_uuid.uuid);
 357                         imp->imp_pingable = imp->imp_replayable = 1;
 358                 } else {
 359                         imp->imp_replayable = 0;
 360                 }
 361                 imp->imp_remote_handle = request->rq_repmsg->handle;
 362                 IMPORT_SET_STATE(imp, LUSTRE_IMP_FULL);
 363                 GOTO(finish, rc = 0);
 364         }
 365
 366         /* Determine what recovery state to move the import to. */
 367         if (MSG_CONNECT_RECONNECT & msg_flags) {
 368                 memset(&old_hdl, 0, sizeof(old_hdl));
 369                 if (!memcmp(&old_hdl, &request->rq_repmsg->handle,
 370                             sizeof (old_hdl))) {
 371                         CERROR("%s@%s didn't like our handle "LPX64
 372                                ", failed\n", imp->imp_target_uuid.uuid,
 373                                imp->imp_connection->c_remote_uuid.uuid,
 374                                imp->imp_dlm_handle.cookie);
 375                         GOTO(out, rc = -ENOTCONN);
 376                 }
 377
 378                 if (memcmp(&imp->imp_remote_handle, &request->rq_repmsg->handle,
 379                            sizeof(imp->imp_remote_handle))) {
 380                         CERROR("%s@%s changed handle from "LPX64" to "LPX64
 381                                "; copying, but this may foreshadow disaster\n",
 382                                imp->imp_target_uuid.uuid,
 383                                imp->imp_connection->c_remote_uuid.uuid,
 384                                imp->imp_remote_handle.cookie,
 385                                request->rq_repmsg->handle.cookie);
 386                         imp->imp_remote_handle = request->rq_repmsg->handle;
 387                 } else {
 388                         CERROR("reconnected to %s@%s after partition\n",
 389                                imp->imp_target_uuid.uuid,
 390                                imp->imp_connection->c_remote_uuid.uuid);
 391                 }
 392
 393                 if (imp->imp_invalid)
 394                         IMPORT_SET_STATE(imp, LUSTRE_IMP_EVICTED);
 395                 else
 396                         IMPORT_SET_STATE(imp, LUSTRE_IMP_RECOVER);
 397         } else if ((MSG_CONNECT_RECOVERING & msg_flags) && !imp->imp_invalid) {
 398                 LASSERT(imp->imp_replayable);
 399                 imp->imp_remote_handle = request->rq_repmsg->handle;
 400                 IMPORT_SET_STATE(imp, LUSTRE_IMP_REPLAY);
 401         } else {
 402                 imp->imp_remote_handle = request->rq_repmsg->handle;
 403                 IMPORT_SET_STATE(imp, LUSTRE_IMP_EVICTED);
 404         }
 405
 406         /* Sanity checks for a reconnected import. */
 407         if (!(imp->imp_replayable) != !(msg_flags & MSG_CONNECT_REPLAYABLE)) {
 408                 CERROR("imp_replayable flag does not match server "
 409                        "after reconnect. We should LBUG right here.\n");
 410         }
 411
 412         if (request->rq_repmsg->last_committed < aa->pcaa_peer_committed) {
 413                 CERROR("%s went back in time (transno "LPD64
 414                        " was previously committed, server now claims "LPD64
 415                        ")! is shared storage not coherent?\n",
 416                        imp->imp_target_uuid.uuid,
 417                        aa->pcaa_peer_committed,
 418                        request->rq_repmsg->last_committed);
 419         }
 420
 421 finish:
 422         rc = ptlrpc_import_recovery_state_machine(imp);
 423         if (rc != 0) {
 424                 if (rc == -ENOTCONN) {
 425                         CDEBUG(D_HA, "evicted/aborted by %s@%s during recovery;"
 426                                "invalidating and reconnecting\n",
 427                                imp->imp_target_uuid.uuid,
 428                                imp->imp_connection->c_remote_uuid.uuid);
 429                         ptlrpc_connect_import(imp, NULL);
 430                         RETURN(0);
 431                 }
 432         }
 433  out:
 434         if (rc != 0) {
 435                 IMPORT_SET_STATE(imp, LUSTRE_IMP_DISCON);
 436                 if (aa->pcaa_initial_connect && !imp->imp_initial_recov) {
 437                         ptlrpc_deactivate_import(imp);
 438                 }
 439                 CDEBUG(D_ERROR, "recovery of %s on %s failed (%d)\n",
 440                        imp->imp_target_uuid.uuid,
 441                        (char *)imp->imp_connection->c_remote_uuid.uuid, rc);
 442         }
 443
 444         wake_up(&imp->imp_recovery_waitq);
 445         RETURN(rc);
 446 }
 447
 448 static int completed_replay_interpret(struct ptlrpc_request *req,
 449                                     void * data, int rc)
 450 {
 451         atomic_dec(&req->rq_import->imp_replay_inflight);
 452         ptlrpc_import_recovery_state_machine(req->rq_import);
 453         RETURN(0);
 454 }
 455
 456 static int signal_completed_replay(struct obd_import *imp)
 457  {
 458         struct ptlrpc_request *req;
 459         ENTRY;
 460
 461         LASSERT(atomic_read(&imp->imp_replay_inflight) == 0);
 462         atomic_inc(&imp->imp_replay_inflight);
 463
 464         req = ptlrpc_prep_req(imp, OBD_PING, 0, NULL, NULL);
 465         if (!req)
 466                 RETURN(-ENOMEM);
 467
 468         req->rq_replen = lustre_msg_size(0, NULL);
 469         req->rq_send_state = LUSTRE_IMP_REPLAY_WAIT;
 470         req->rq_reqmsg->flags |= MSG_LAST_REPLAY;
 471         req->rq_timeout *= 3;
 472         req->rq_interpret_reply = completed_replay_interpret;
 473
 474         ptlrpcd_add_req(req);
 475         RETURN(0);
 476 }
 477
 478 int ptlrpc_import_recovery_state_machine(struct obd_import *imp)
 479 {
 480         int rc = 0;
 481         int inflight;
 482
 483         if (imp->imp_state == LUSTRE_IMP_EVICTED) {
 484                 CDEBUG(D_HA, "evicted from %s@%s; invalidating\n",
 485                        imp->imp_target_uuid.uuid,
 486                        imp->imp_connection->c_remote_uuid.uuid);
 487
 488                 ptlrpc_invalidate_import(imp, 1);
 489
 490                 IMPORT_SET_STATE(imp, LUSTRE_IMP_RECOVER);
 491         }
 492
 493         if (imp->imp_state == LUSTRE_IMP_REPLAY) {
 494                 CDEBUG(D_HA, "replay requested by %s\n",
 495                        imp->imp_target_uuid.uuid);
 496                 rc = ptlrpc_replay_next(imp, &inflight);
 497                 if (inflight == 0 &&
 498                     atomic_read(&imp->imp_replay_inflight) == 0) {
 499                         IMPORT_SET_STATE(imp, LUSTRE_IMP_REPLAY_LOCKS);
 500                         rc = ldlm_replay_locks(imp);
 501                         if (rc)
 502                                 GOTO(out, rc);
 503                 }
 504                 rc = 0;
 505         }
 506
 507         if (imp->imp_state == LUSTRE_IMP_REPLAY_LOCKS) {
 508                 if (atomic_read(&imp->imp_replay_inflight) == 0) {
 509                         IMPORT_SET_STATE(imp, LUSTRE_IMP_REPLAY_WAIT);
 510                         rc = signal_completed_replay(imp);
 511                         if (rc)
 512                                 GOTO(out, rc);
 513                 }
 514
 515         }
 516
 517         if (imp->imp_state == LUSTRE_IMP_REPLAY_WAIT) {
 518                 if (atomic_read(&imp->imp_replay_inflight) == 0) {
 519                         IMPORT_SET_STATE(imp, LUSTRE_IMP_RECOVER);
 520                 }
 521         }
 522
 523         if (imp->imp_state == LUSTRE_IMP_RECOVER) {
 524                 CDEBUG(D_HA, "reconnected to %s@%s\n",
 525                        imp->imp_target_uuid.uuid,
 526                        imp->imp_connection->c_remote_uuid.uuid);
 527
 528                 rc = ptlrpc_resend(imp);
 529                 if (rc)
 530                         GOTO(out, rc);
 531                 IMPORT_SET_STATE(imp, LUSTRE_IMP_FULL);
 532                 ptlrpc_activate_import(imp);
 533         }
 534
 535         if (imp->imp_state == LUSTRE_IMP_FULL) {
 536                 wake_up(&imp->imp_recovery_waitq);
 537                 ptlrpc_wake_delayed(imp);
 538         }
 539
 540  out:
 541         RETURN(rc);
 542 }
 543
 544 static int back_to_sleep(void *unused)
 545 {
 546         return 0;
 547 }
 548
 549 int ptlrpc_disconnect_import(struct obd_import *imp)
 550 {
 551         struct ptlrpc_request *request;
 552         int rq_opc;
 553         int rc = 0;
 554         unsigned long flags;
 555         ENTRY;
 556
 557         switch (imp->imp_connect_op) {
 558         case OST_CONNECT: rq_opc = OST_DISCONNECT; break;
 559         case MDS_CONNECT: rq_opc = MDS_DISCONNECT; break;
 560         case MGMT_CONNECT:rq_opc = MGMT_DISCONNECT;break;
 561         default:
 562                 CERROR("don't know how to disconnect from %s (connect_op %d)\n",
 563                        imp->imp_target_uuid.uuid, imp->imp_connect_op);
 564                 RETURN(-EINVAL);
 565         }
 566
 567
 568         if (ptlrpc_import_in_recovery(imp)) {
 569                 struct l_wait_info lwi;
 570                 lwi = LWI_TIMEOUT_INTR(MAX(obd_timeout * HZ, 1), back_to_sleep,
 571                                        NULL, NULL);
 572                 rc = l_wait_event(imp->imp_recovery_waitq,
 573                                   !ptlrpc_import_in_recovery(imp), &lwi);
 574
 575         }
 576
 577         spin_lock_irqsave(&imp->imp_lock, flags);
 578         if (imp->imp_state != LUSTRE_IMP_FULL) {
 579                 GOTO(out, 0);
 580         }
 581         spin_unlock_irqrestore(&imp->imp_lock, flags);
 582
 583         request = ptlrpc_prep_req(imp, rq_opc, 0, NULL, NULL);
 584         if (request) {
 585                 /* For non-replayable connections, don't attempt
 586                    reconnect if this fails */
 587                 if (!imp->imp_replayable) {
 588                         request->rq_no_resend = 1;
 589                         IMPORT_SET_STATE(imp, LUSTRE_IMP_CONNECTING);
 590                         request->rq_send_state =  LUSTRE_IMP_CONNECTING;
 591                 }
 592                 request->rq_replen = lustre_msg_size(0, NULL);
 593                 rc = ptlrpc_queue_wait(request);
 594                 ptlrpc_req_finished(request);
 595         }
 596
 597         spin_lock_irqsave(&imp->imp_lock, flags);
 598 out:
 599         IMPORT_SET_STATE_NOLOCK(imp, LUSTRE_IMP_CLOSED);
 600         memset(&imp->imp_remote_handle, 0, sizeof(imp->imp_remote_handle));
 601         spin_unlock_irqrestore(&imp->imp_lock, flags);
 602
 603         RETURN(rc);
 604 }
 605