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         unsigned long timeout;
 152         int inflight = 0;
 153         int rc;
 154
 155         if (!imp->imp_invalid)
 156                 ptlrpc_deactivate_import(imp);
 157
 158         LASSERT(imp->imp_invalid);
 159
 160         if (in_rpc)
 161                 inflight = 1;
 162         /* wait for all requests to error out and call completion
 163            callbacks */
 164         if (imp->imp_server_timeout)
 165                 timeout = obd_timeout / 2;
 166         else
 167                 timeout = obd_timeout;
 168         timeout = MAX(timeout * HZ, 1);
 169         lwi = LWI_TIMEOUT_INTR(timeout, NULL, NULL, NULL);
 170         rc = l_wait_event(imp->imp_recovery_waitq,
 171                           (atomic_read(&imp->imp_inflight) == inflight),
 172                           &lwi);
 173
 174         if (rc)
 175                 CERROR("%s: rc = %d waiting for callback (%d != %d)\n",
 176                        imp->imp_target_uuid.uuid, rc,
 177                        atomic_read(&imp->imp_inflight), inflight);
 178
 179         obd_import_event(imp->imp_obd, imp, IMP_EVENT_INVALIDATE);
 180 }
 181
 182 static void ptlrpc_activate_import(struct obd_import *imp)
 183 {
 184         struct obd_device *obd = imp->imp_obd;
 185         unsigned long flags;
 186
 187         spin_lock_irqsave(&imp->imp_lock, flags);
 188         imp->imp_invalid = 0;
 189         spin_unlock_irqrestore(&imp->imp_lock, flags);
 190
 191         obd_import_event(obd, imp, IMP_EVENT_ACTIVE);
 192 }
 193
 194 void ptlrpc_fail_import(struct obd_import *imp, int generation)
 195 {
 196         ENTRY;
 197
 198         LASSERT (!imp->imp_dlm_fake);
 199
 200         if (ptlrpc_set_import_discon(imp)) {
 201                 unsigned long flags;
 202
 203                 if (!imp->imp_replayable) {
 204                         CDEBUG(D_HA, "import %s@%s for %s not replayable, "
 205                                "auto-deactivating\n",
 206                                imp->imp_target_uuid.uuid,
 207                                imp->imp_connection->c_remote_uuid.uuid,
 208                                imp->imp_obd->obd_name);
 209                         ptlrpc_deactivate_import(imp);
 210                 }
 211
 212                 CDEBUG(D_HA, "%s: waking up pinger\n",
 213                        imp->imp_target_uuid.uuid);
 214
 215                 spin_lock_irqsave(&imp->imp_lock, flags);
 216                 imp->imp_force_verify = 1;
 217                 spin_unlock_irqrestore(&imp->imp_lock, flags);
 218
 219                 ptlrpc_pinger_wake_up();
 220
 221         }
 222         EXIT;
 223 }
 224
 225 int ptlrpc_connect_import(struct obd_import *imp, char * new_uuid)
 226 {
 227         struct obd_device *obd = imp->imp_obd;
 228         int initial_connect = 0;
 229         int rc;
 230         __u64 committed_before_reconnect = 0;
 231         struct ptlrpc_request *request;
 232         int size[] = {sizeof(imp->imp_target_uuid),
 233                                  sizeof(obd->obd_uuid),
 234                                  sizeof(imp->imp_dlm_handle)};
 235         char *tmp[] = {imp->imp_target_uuid.uuid,
 236                        obd->obd_uuid.uuid,
 237                        (char *)&imp->imp_dlm_handle};
 238         struct ptlrpc_connect_async_args *aa;
 239         unsigned long flags;
 240
 241         spin_lock_irqsave(&imp->imp_lock, flags);
 242         if (imp->imp_state == LUSTRE_IMP_CLOSED) {
 243                 spin_unlock_irqrestore(&imp->imp_lock, flags);
 244                 CERROR("can't connect to a closed import\n");
 245                 RETURN(-EINVAL);
 246         } else if (imp->imp_state == LUSTRE_IMP_FULL) {
 247                 spin_unlock_irqrestore(&imp->imp_lock, flags);
 248                 CERROR("already connected\n");
 249                 RETURN(0);
 250         } else if (imp->imp_state == LUSTRE_IMP_CONNECTING) {
 251                 spin_unlock_irqrestore(&imp->imp_lock, flags);
 252                 CERROR("already connecting\n");
 253                 RETURN(-EALREADY);
 254         }
 255
 256         IMPORT_SET_STATE_NOLOCK(imp, LUSTRE_IMP_CONNECTING);
 257
 258         imp->imp_conn_cnt++;
 259         imp->imp_last_replay_transno = 0;
 260
 261         if (imp->imp_remote_handle.cookie == 0) {
 262                 initial_connect = 1;
 263         } else {
 264                 committed_before_reconnect = imp->imp_peer_committed_transno;;
 265
 266         }
 267
 268
 269         spin_unlock_irqrestore(&imp->imp_lock, flags);
 270
 271         if (new_uuid) {
 272                 struct ptlrpc_connection *conn;
 273                 struct obd_uuid uuid;
 274                 struct obd_export *dlmexp;
 275
 276                 obd_str2uuid(&uuid, new_uuid);
 277
 278                 conn = ptlrpc_uuid_to_connection(&uuid);
 279                 if (!conn)
 280                         GOTO(out, rc = -ENOENT);
 281
 282                 CDEBUG(D_HA, "switching import %s/%s from %s to %s\n",
 283                        imp->imp_target_uuid.uuid, imp->imp_obd->obd_name,
 284                        imp->imp_connection->c_remote_uuid.uuid,
 285                        conn->c_remote_uuid.uuid);
 286
 287                 /* Switch the import's connection and the DLM export's
 288                  * connection (which are almost certainly the same, but we
 289                  * keep distinct refs just to make things clearer. I think. */
 290                 if (imp->imp_connection)
 291                         ptlrpc_put_connection(imp->imp_connection);
 292                 /* We hand off the ref from ptlrpc_get_connection. */
 293                 imp->imp_connection = conn;
 294
 295                 dlmexp = class_conn2export(&imp->imp_dlm_handle);
 296
 297                 LASSERT(dlmexp != NULL);
 298
 299                 if (dlmexp->exp_connection)
 300                         ptlrpc_put_connection(dlmexp->exp_connection);
 301                 dlmexp->exp_connection = ptlrpc_connection_addref(conn);
 302                 class_export_put(dlmexp);
 303
 304         }
 305
 306         request = ptlrpc_prep_req(imp, imp->imp_connect_op, 3, size, tmp);
 307         if (!request)
 308                 GOTO(out, rc = -ENOMEM);
 309
 310 #ifndef __KERNEL__
 311         lustre_msg_add_op_flags(request->rq_reqmsg, MSG_CONNECT_LIBCLIENT);
 312 #endif
 313
 314         request->rq_send_state = LUSTRE_IMP_CONNECTING;
 315         request->rq_replen = lustre_msg_size(0, NULL);
 316         request->rq_interpret_reply = ptlrpc_connect_interpret;
 317
 318         LASSERT (sizeof (*aa) <= sizeof (request->rq_async_args));
 319         aa = (struct ptlrpc_connect_async_args *)&request->rq_async_args;
 320         memset(aa, 0, sizeof *aa);
 321
 322         aa->pcaa_peer_committed = committed_before_reconnect;
 323         aa->pcaa_initial_connect = initial_connect;
 324
 325         if (aa->pcaa_initial_connect)
 326                 imp->imp_replayable = 1;
 327
 328         ptlrpcd_add_req(request);
 329         rc = 0;
 330 out:
 331         if (rc != 0) {
 332                 IMPORT_SET_STATE(imp, LUSTRE_IMP_DISCON);
 333         }
 334
 335         RETURN(rc);
 336 }
 337
 338 static int ptlrpc_connect_interpret(struct ptlrpc_request *request,
 339                                     void * data, int rc)
 340 {
 341         struct ptlrpc_connect_async_args *aa = data;
 342         struct obd_import *imp = request->rq_import;
 343         struct lustre_handle old_hdl;
 344         unsigned long flags;
 345         int msg_flags;
 346         ENTRY;
 347
 348         spin_lock_irqsave(&imp->imp_lock, flags);
 349         if (imp->imp_state == LUSTRE_IMP_CLOSED) {
 350                 spin_unlock_irqrestore(&imp->imp_lock, flags);
 351                 RETURN(0);
 352         }
 353         spin_unlock_irqrestore(&imp->imp_lock, flags);
 354
 355         if (rc)
 356                 GOTO(out, rc);
 357
 358         msg_flags = lustre_msg_get_op_flags(request->rq_repmsg);
 359
 360         if (aa->pcaa_initial_connect) {
 361                 if (msg_flags & MSG_CONNECT_REPLAYABLE) {
 362                         CDEBUG(D_HA, "connected to replayable target: %s\n",
 363                                imp->imp_target_uuid.uuid);
 364                         imp->imp_pingable = imp->imp_replayable = 1;
 365                 } else {
 366                         imp->imp_replayable = 0;
 367                 }
 368                 imp->imp_remote_handle = request->rq_repmsg->handle;
 369                 IMPORT_SET_STATE(imp, LUSTRE_IMP_FULL);
 370                 GOTO(finish, rc = 0);
 371         }
 372
 373         /* Determine what recovery state to move the import to. */
 374         if (MSG_CONNECT_RECONNECT & msg_flags) {
 375                 memset(&old_hdl, 0, sizeof(old_hdl));
 376                 if (!memcmp(&old_hdl, &request->rq_repmsg->handle,
 377                             sizeof (old_hdl))) {
 378                         CERROR("%s@%s didn't like our handle "LPX64
 379                                ", failed\n", imp->imp_target_uuid.uuid,
 380                                imp->imp_connection->c_remote_uuid.uuid,
 381                                imp->imp_dlm_handle.cookie);
 382                         GOTO(out, rc = -ENOTCONN);
 383                 }
 384
 385                 if (memcmp(&imp->imp_remote_handle, &request->rq_repmsg->handle,
 386                            sizeof(imp->imp_remote_handle))) {
 387                         CERROR("%s@%s changed handle from "LPX64" to "LPX64
 388                                "; copying, but this may foreshadow disaster\n",
 389                                imp->imp_target_uuid.uuid,
 390                                imp->imp_connection->c_remote_uuid.uuid,
 391                                imp->imp_remote_handle.cookie,
 392                                request->rq_repmsg->handle.cookie);
 393                         imp->imp_remote_handle = request->rq_repmsg->handle;
 394                 } else {
 395                         CERROR("reconnected to %s@%s after partition\n",
 396                                imp->imp_target_uuid.uuid,
 397                                imp->imp_connection->c_remote_uuid.uuid);
 398                 }
 399
 400                 if (imp->imp_invalid)
 401                         IMPORT_SET_STATE(imp, LUSTRE_IMP_EVICTED);
 402                 else
 403                         IMPORT_SET_STATE(imp, LUSTRE_IMP_RECOVER);
 404         }
 405         else if ((MSG_CONNECT_RECOVERING & msg_flags) && !imp->imp_invalid) {
 406                 LASSERT(imp->imp_replayable);
 407                 imp->imp_remote_handle = request->rq_repmsg->handle;
 408                 IMPORT_SET_STATE(imp, LUSTRE_IMP_REPLAY);
 409         }
 410         else {
 411                 imp->imp_remote_handle = request->rq_repmsg->handle;
 412                 IMPORT_SET_STATE(imp, LUSTRE_IMP_EVICTED);
 413         }
 414
 415         /* Sanity checks for a reconnected import. */
 416         if (!(imp->imp_replayable) !=
 417              !(msg_flags & MSG_CONNECT_REPLAYABLE)) {
 418                 CERROR("imp_replayable flag does not match server "
 419                        "after reconnect. We should LBUG right here.\n");
 420         }
 421
 422         if (request->rq_repmsg->last_committed < aa->pcaa_peer_committed) {
 423                 CERROR("%s went back in time (transno "LPD64
 424                        " was previously committed, server now claims "LPD64
 425                        ")! is shared storage not coherent?\n",
 426                        imp->imp_target_uuid.uuid,
 427                        aa->pcaa_peer_committed,
 428                        request->rq_repmsg->last_committed);
 429         }
 430
 431 finish:
 432         rc = ptlrpc_import_recovery_state_machine(imp);
 433         if (rc != 0) {
 434                 if (rc == -ENOTCONN) {
 435                         CDEBUG(D_HA, "evicted/aborted by %s@%s during recovery;"
 436                                "invalidating and reconnecting\n",
 437                                imp->imp_target_uuid.uuid,
 438                                imp->imp_connection->c_remote_uuid.uuid);
 439                         ptlrpc_connect_import(imp, NULL);
 440                         RETURN(0);
 441                 }
 442         }
 443  out:
 444         if (rc != 0) {
 445                 IMPORT_SET_STATE(imp, LUSTRE_IMP_DISCON);
 446                 if (aa->pcaa_initial_connect && !imp->imp_initial_recov) {
 447                         ptlrpc_deactivate_import(imp);
 448                 }
 449                 /*if (rc == -ETIMEDOUT) {
 450                         CDEBUG(D_ERROR, "recovery of %s on %s failed (timeout)\n",
 451                                imp->imp_target_uuid.uuid,
 452                                (char *)imp->imp_connection->c_remote_uuid.uuid);
 453                         ptlrpc_connect_import(imp, NULL);
 454                         RETURN(0);
 455                 }*/
 456                 CDEBUG(D_ERROR, "recovery of %s on %s failed (%d)\n",
 457                        imp->imp_target_uuid.uuid,
 458                        (char *)imp->imp_connection->c_remote_uuid.uuid, rc);
 459         }
 460
 461         wake_up(&imp->imp_recovery_waitq);
 462         RETURN(rc);
 463 }
 464
 465 static int completed_replay_interpret(struct ptlrpc_request *req,
 466                                     void * data, int rc)
 467 {
 468         atomic_dec(&req->rq_import->imp_replay_inflight);
 469         ptlrpc_import_recovery_state_machine(req->rq_import);
 470         RETURN(0);
 471 }
 472
 473 static int signal_completed_replay(struct obd_import *imp)
 474  {
 475         struct ptlrpc_request *req;
 476         ENTRY;
 477
 478         LASSERT(atomic_read(&imp->imp_replay_inflight) == 0);
 479         atomic_inc(&imp->imp_replay_inflight);
 480
 481         req = ptlrpc_prep_req(imp, OBD_PING, 0, NULL, NULL);
 482         if (!req)
 483                 RETURN(-ENOMEM);
 484
 485         req->rq_replen = lustre_msg_size(0, NULL);
 486         req->rq_send_state = LUSTRE_IMP_REPLAY_WAIT;
 487         req->rq_reqmsg->flags |= MSG_LAST_REPLAY;
 488         req->rq_timeout *= 3;
 489         req->rq_interpret_reply = completed_replay_interpret;
 490
 491         ptlrpcd_add_req(req);
 492         RETURN(0);
 493 }
 494
 495 int ptlrpc_import_recovery_state_machine(struct obd_import *imp)
 496 {
 497         int rc = 0;
 498         int inflight;
 499
 500         if (imp->imp_state == LUSTRE_IMP_EVICTED) {
 501                 CDEBUG(D_HA, "evicted from %s@%s; invalidating\n",
 502                        imp->imp_target_uuid.uuid,
 503                        imp->imp_connection->c_remote_uuid.uuid);
 504
 505                 ptlrpc_invalidate_import(imp, 1);
 506
 507                 IMPORT_SET_STATE(imp, LUSTRE_IMP_RECOVER);
 508         }
 509
 510         if (imp->imp_state == LUSTRE_IMP_REPLAY) {
 511                 CDEBUG(D_HA, "replay requested by %s\n",
 512                        imp->imp_target_uuid.uuid);
 513                 rc = ptlrpc_replay_next(imp, &inflight);
 514                 if (inflight == 0 &&
 515                     atomic_read(&imp->imp_replay_inflight) == 0) {
 516                         IMPORT_SET_STATE(imp, LUSTRE_IMP_REPLAY_LOCKS);
 517                         rc = ldlm_replay_locks(imp);
 518                         if (rc)
 519                                 GOTO(out, rc);
 520                 }
 521                 rc = 0;
 522         }
 523
 524         if (imp->imp_state == LUSTRE_IMP_REPLAY_LOCKS) {
 525                 if (atomic_read(&imp->imp_replay_inflight) == 0) {
 526                         IMPORT_SET_STATE(imp, LUSTRE_IMP_REPLAY_WAIT);
 527                         rc = signal_completed_replay(imp);
 528                         if (rc)
 529                                 GOTO(out, rc);
 530                 }
 531
 532         }
 533
 534         if (imp->imp_state == LUSTRE_IMP_REPLAY_WAIT) {
 535                 if (atomic_read(&imp->imp_replay_inflight) == 0) {
 536                         IMPORT_SET_STATE(imp, LUSTRE_IMP_RECOVER);
 537                 }
 538         }
 539
 540         if (imp->imp_state == LUSTRE_IMP_RECOVER) {
 541                 CDEBUG(D_HA, "reconnected to %s@%s\n",
 542                        imp->imp_target_uuid.uuid,
 543                        imp->imp_connection->c_remote_uuid.uuid);
 544
 545                 rc = ptlrpc_resend(imp);
 546                 if (rc)
 547                         GOTO(out, rc);
 548                 IMPORT_SET_STATE(imp, LUSTRE_IMP_FULL);
 549                 ptlrpc_activate_import(imp);
 550         }
 551
 552         if (imp->imp_state == LUSTRE_IMP_FULL) {
 553                 wake_up(&imp->imp_recovery_waitq);
 554                 ptlrpc_wake_delayed(imp);
 555         }
 556
 557  out:
 558         RETURN(rc);
 559 }
 560
 561 static int back_to_sleep(void *unused)
 562 {
 563         return 0;
 564 }
 565
 566 int ptlrpc_disconnect_import(struct obd_import *imp)
 567 {
 568         struct ptlrpc_request *request;
 569         int rq_opc;
 570         int rc = 0;
 571         unsigned long flags;
 572         ENTRY;
 573
 574         switch (imp->imp_connect_op) {
 575         case OST_CONNECT: rq_opc = OST_DISCONNECT; break;
 576         case MDS_CONNECT: rq_opc = MDS_DISCONNECT; break;
 577         case MGMT_CONNECT:rq_opc = MGMT_DISCONNECT;break;
 578         default:
 579                 CERROR("don't know how to disconnect from %s (connect_op %d)\n",
 580                        imp->imp_target_uuid.uuid, imp->imp_connect_op);
 581                 RETURN(-EINVAL);
 582         }
 583
 584
 585         if (ptlrpc_import_in_recovery(imp)) {
 586                 struct l_wait_info lwi;
 587                 unsigned long timeout;
 588                 if (imp->imp_server_timeout)
 589                         timeout = obd_timeout / 2;
 590                 else
 591                         timeout = obd_timeout;
 592                 timeout = MAX(timeout * HZ, 1);
 593                 lwi = LWI_TIMEOUT_INTR(obd_timeout, back_to_sleep, NULL, NULL);
 594                 rc = l_wait_event(imp->imp_recovery_waitq,
 595                                   !ptlrpc_import_in_recovery(imp), &lwi);
 596
 597         }
 598
 599         spin_lock_irqsave(&imp->imp_lock, flags);
 600         if (imp->imp_state != LUSTRE_IMP_FULL) {
 601                 GOTO(out, 0);
 602         }
 603         spin_unlock_irqrestore(&imp->imp_lock, flags);
 604
 605         request = ptlrpc_prep_req(imp, rq_opc, 0, NULL, NULL);
 606         if (request) {
 607                 /* For non-replayable connections, don't attempt
 608                    reconnect if this fails */
 609                 if (!imp->imp_replayable) {
 610                         request->rq_no_resend = 1;
 611                         IMPORT_SET_STATE(imp, LUSTRE_IMP_CONNECTING);
 612                         request->rq_send_state =  LUSTRE_IMP_CONNECTING;
 613                 }
 614                 request->rq_replen = lustre_msg_size(0, NULL);
 615                 rc = ptlrpc_queue_wait(request);
 616                 ptlrpc_req_finished(request);
 617         }
 618
 619         spin_lock_irqsave(&imp->imp_lock, flags);
 620 out:
 621         IMPORT_SET_STATE_NOLOCK(imp, LUSTRE_IMP_CLOSED);
 622         memset(&imp->imp_remote_handle, 0, sizeof(imp->imp_remote_handle));
 623         spin_unlock_irqrestore(&imp->imp_lock, flags);
 624
 625         RETURN(rc);
 626 }
 627