lustre/ptlrpc/recover.c

   1 /* -*- mode: c; c-basic-offset: 8; indent-tabs-mode: nil; -*-
   2  * vim:expandtab:shiftwidth=8:tabstop=8:
   3  *
   4  * Portal-RPC reconnection and replay operations, for use in recovery.
   5  *
   6  *  Copyright (c) 2002, 2003 Cluster File Systems, Inc.
   7  *   Author: Mike Shaver <shaver@clusterfs.com>
   8  *
   9  *   This file is part of Lustre, http://www.lustre.org.
  10  *
  11  *   Lustre is free software; you can redistribute it and/or
  12  *   modify it under the terms of version 2 of the GNU General Public
  13  *   License as published by the Free Software Foundation.
  14  *
  15  *   Lustre is distributed in the hope that it will be useful,
  16  *   but WITHOUT ANY WARRANTY; without even the implied warranty of
  17  *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  18  *   GNU General Public License for more details.
  19  *
  20  *   You should have received a copy of the GNU General Public License
  21  *   along with Lustre; if not, write to the Free Software
  22  *   Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
  23  */
  24
  25 #define DEBUG_SUBSYSTEM S_RPC
  26 #ifdef __KERNEL__
  27 # include <linux/config.h>
  28 # include <linux/module.h>
  29 # include <linux/kmod.h>
  30 #else
  31 # include <liblustre.h>
  32 #endif
  33
  34 #include <linux/obd_support.h>
  35 #include <linux/lustre_ha.h>
  36 #include <linux/lustre_net.h>
  37 #include <linux/lustre_import.h>
  38 #include <linux/lustre_export.h>
  39 #include <linux/obd.h>
  40 #include <linux/obd_class.h>
  41 #include <linux/obd_lov.h> /* for IOC_LOV_SET_OSC_ACTIVE */
  42
  43 #include "ptlrpc_internal.h"
  44
  45 enum reconnect_result {
  46         RECON_RESULT_RECOVERING  =  1,
  47         RECON_RESULT_RECONNECTED  = 2,
  48         RECON_RESULT_EVICTED      = 3,
  49 };
  50
  51 int ptlrpc_reconnect_import(struct obd_import *imp)
  52 {
  53         struct obd_device *obd = imp->imp_obd;
  54         int rc, size[] = {sizeof(imp->imp_target_uuid),
  55                                  sizeof(obd->obd_uuid),
  56                                  sizeof(imp->imp_dlm_handle)};
  57         char *tmp[] = {imp->imp_target_uuid.uuid,
  58                        obd->obd_uuid.uuid,
  59                        (char *)&imp->imp_dlm_handle};
  60         struct ptlrpc_connection *conn = imp->imp_connection;
  61         struct ptlrpc_request *req;
  62         struct lustre_handle old_hdl;
  63         __u64 committed_before_reconnect = imp->imp_peer_committed_transno;
  64
  65         CERROR("reconnect handle "LPX64"\n",
  66                imp->imp_dlm_handle.cookie);
  67
  68         req = ptlrpc_prep_req(imp, imp->imp_connect_op, 3, size, tmp);
  69         if (!req)
  70                 RETURN(-ENOMEM);
  71         req->rq_level = LUSTRE_CONN_NEW;
  72         req->rq_replen = lustre_msg_size(0, NULL);
  73         rc = ptlrpc_queue_wait(req);
  74         if (rc) {
  75                 /* what if rc > 0 ??*/
  76                 CERROR("cannot connect to %s@%s: rc = %d\n",
  77                        imp->imp_target_uuid.uuid, conn->c_remote_uuid.uuid, rc);
  78                 GOTO(out_disc, rc);
  79         }
  80
  81         if (lustre_msg_get_op_flags(req->rq_repmsg) & MSG_CONNECT_RECONNECT) {
  82                 memset(&old_hdl, 0, sizeof(old_hdl));
  83                 if (!memcmp(&old_hdl, &req->rq_repmsg->handle,
  84                             sizeof (old_hdl))) {
  85                         CERROR("%s@%s didn't like our handle "LPX64
  86                                ", failed\n", imp->imp_target_uuid.uuid,
  87                                conn->c_remote_uuid.uuid,
  88                                imp->imp_dlm_handle.cookie);
  89                         GOTO(out_disc, rc = -ENOTCONN);
  90                 }
  91
  92                 if (memcmp(&imp->imp_remote_handle, &req->rq_repmsg->handle,
  93                            sizeof(imp->imp_remote_handle))) {
  94                         CERROR("%s@%s changed handle from "LPX64" to "LPX64
  95                                "; copying, but this may foreshadow disaster\n",
  96                                imp->imp_target_uuid.uuid,
  97                                conn->c_remote_uuid.uuid,
  98                                imp->imp_remote_handle.cookie,
  99                                req->rq_repmsg->handle.cookie);
 100                         imp->imp_remote_handle = req->rq_repmsg->handle;
 101                         GOTO(out_disc, rc = RECON_RESULT_RECONNECTED);
 102                 }
 103
 104                 CERROR("reconnected to %s@%s after partition\n",
 105                        imp->imp_target_uuid.uuid, conn->c_remote_uuid.uuid);
 106                 GOTO(out_disc, rc = RECON_RESULT_RECONNECTED);
 107         } else if (lustre_msg_get_op_flags(req->rq_repmsg) &
 108                    MSG_CONNECT_RECOVERING) {
 109                 rc = RECON_RESULT_RECOVERING;
 110         } else {
 111                 rc = RECON_RESULT_EVICTED;
 112         }
 113
 114         old_hdl = imp->imp_remote_handle;
 115         imp->imp_remote_handle = req->rq_repmsg->handle;
 116         CERROR("reconnected to %s@%s ("LPX64", was "LPX64")!\n",
 117                imp->imp_target_uuid.uuid, conn->c_remote_uuid.uuid,
 118                imp->imp_remote_handle.cookie, old_hdl.cookie);
 119         if (req->rq_repmsg->last_committed < committed_before_reconnect) {
 120                 CERROR("%s went back in time (transno "LPD64
 121                        " was committed, server claims "LPD64
 122                        ")! is shared storage not coherent?\n",
 123                        imp->imp_target_uuid.uuid,
 124                        imp->imp_peer_committed_transno,
 125                        req->rq_repmsg->last_committed);
 126         }
 127
 128         GOTO(out_disc, rc);
 129
 130  out_disc:
 131         ptlrpc_req_finished(req);
 132         return rc;
 133 }
 134
 135 void ptlrpc_run_recovery_over_upcall(struct obd_device *obd)
 136 {
 137         char *argv[4];
 138         char *envp[3];
 139         int rc;
 140
 141         ENTRY;
 142         argv[0] = obd_lustre_upcall;
 143         argv[1] = "RECOVERY_OVER";
 144         argv[2] = obd->obd_uuid.uuid;
 145         argv[3] = NULL;
 146
 147         envp[0] = "HOME=/";
 148         envp[1] = "PATH=/sbin:/bin:/usr/sbin:/usr/bin";
 149         envp[2] = NULL;
 150
 151         rc = USERMODEHELPER(argv[0], argv, envp);
 152         if (rc < 0) {
 153                 CERROR("Error invoking recovery upcall %s %s %s: %d; check "
 154                        "/proc/sys/lustre/upcall\n",
 155                        argv[0], argv[1], argv[2], rc);
 156
 157         } else {
 158                 CERROR("Invoked upcall %s %s %s",
 159                        argv[0], argv[1], argv[2]);
 160         }
 161 }
 162
 163 void ptlrpc_run_failed_import_upcall(struct obd_import* imp)
 164 {
 165         char *argv[7];
 166         char *envp[3];
 167         int rc;
 168
 169         ENTRY;
 170         argv[0] = obd_lustre_upcall;
 171         argv[1] = "FAILED_IMPORT";
 172         argv[2] = imp->imp_target_uuid.uuid;
 173         argv[3] = imp->imp_obd->obd_name;
 174         argv[4] = imp->imp_connection->c_remote_uuid.uuid;
 175         argv[5] = imp->imp_obd->obd_uuid.uuid;
 176         argv[6] = NULL;
 177
 178         envp[0] = "HOME=/";
 179         envp[1] = "PATH=/sbin:/bin:/usr/sbin:/usr/bin";
 180         envp[2] = NULL;
 181
 182         rc = USERMODEHELPER(argv[0], argv, envp);
 183         if (rc < 0) {
 184                 CERROR("Error invoking recovery upcall %s %s %s %s %s: %d; "
 185                        "check /proc/sys/lustre/lustre_upcall\n",
 186                        argv[0], argv[1], argv[2], argv[3], argv[4],rc);
 187
 188         } else {
 189                 CERROR("Invoked upcall %s %s %s %s %s\n",
 190                        argv[0], argv[1], argv[2], argv[3], argv[4]);
 191         }
 192 }
 193
 194 int ptlrpc_replay(struct obd_import *imp)
 195 {
 196         int rc = 0;
 197         struct list_head *tmp, *pos;
 198         struct ptlrpc_request *req;
 199         unsigned long flags;
 200         ENTRY;
 201
 202         /* It might have committed some after we last spoke, so make sure we
 203          * get rid of them now.
 204          */
 205         spin_lock_irqsave(&imp->imp_lock, flags);
 206         ptlrpc_free_committed(imp);
 207         spin_unlock_irqrestore(&imp->imp_lock, flags);
 208
 209         CDEBUG(D_HA, "import %p from %s has committed "LPD64"\n",
 210                imp, imp->imp_target_uuid.uuid, imp->imp_peer_committed_transno);
 211
 212         list_for_each(tmp, &imp->imp_replay_list) {
 213                 req = list_entry(tmp, struct ptlrpc_request, rq_list);
 214                 DEBUG_REQ(D_HA, req, "RETAINED: ");
 215         }
 216
 217         /* Do I need to hold a lock across this iteration?  We shouldn't be
 218          * racing with any additions to the list, because we're in recovery
 219          * and are therefore not processing additional requests to add.  Calls
 220          * to ptlrpc_free_committed might commit requests, but nothing "newer"
 221          * than the one we're replaying (it can't be committed until it's
 222          * replayed, and we're doing that here).  l_f_e_safe protects against
 223          * problems with the current request being committed, in the unlikely
 224          * event of that race.  So, in conclusion, I think that it's safe to
 225          * perform this list-walk without the imp_lock held.
 226          *
 227          * But, the {mdc,osc}_replay_open callbacks both iterate
 228          * request lists, and have comments saying they assume the
 229          * imp_lock is being held by ptlrpc_replay, but it's not. it's
 230          * just a little race...
 231          */
 232         list_for_each_safe(tmp, pos, &imp->imp_replay_list) {
 233                 req = list_entry(tmp, struct ptlrpc_request, rq_list);
 234
 235                 DEBUG_REQ(D_HA, req, "REPLAY:");
 236
 237                 rc = ptlrpc_replay_req(req);
 238
 239                 if (rc) {
 240                         CERROR("recovery replay error %d for req "LPD64"\n",
 241                                rc, req->rq_xid);
 242                         RETURN(rc);
 243                 }
 244         }
 245
 246         RETURN(0);
 247 }
 248
 249 int ptlrpc_resend(struct obd_import *imp)
 250 {
 251         struct list_head *tmp, *pos;
 252         struct ptlrpc_request *req;
 253         unsigned long flags;
 254
 255         ENTRY;
 256
 257         /* As long as we're in recovery, nothing should be added to the sending
 258          * list, so we don't need to hold the lock during this iteration and
 259          * resend process.
 260          */
 261         /* Well... what if lctl recover is called twice at the same time?
 262          */
 263         spin_lock_irqsave(&imp->imp_lock, flags);
 264         LASSERT(imp->imp_level == LUSTRE_CONN_RECOVER);
 265         spin_unlock_irqrestore(&imp->imp_lock, flags);
 266
 267         list_for_each_safe(tmp, pos, &imp->imp_sending_list) {
 268                 req = list_entry(tmp, struct ptlrpc_request, rq_list);
 269                 ptlrpc_resend_req(req);
 270         }
 271
 272         RETURN(0);
 273 }
 274
 275 void ptlrpc_wake_delayed(struct obd_import *imp)
 276 {
 277         unsigned long flags;
 278         struct list_head *tmp, *pos;
 279         struct ptlrpc_request *req;
 280
 281         spin_lock_irqsave(&imp->imp_lock, flags);
 282         list_for_each_safe(tmp, pos, &imp->imp_delayed_list) {
 283                 req = list_entry(tmp, struct ptlrpc_request, rq_list);
 284
 285                 ptlrpc_put_connection(req->rq_connection);
 286                 req->rq_connection =
 287                        ptlrpc_connection_addref(req->rq_import->imp_connection);
 288
 289                 if (req->rq_set) {
 290                         DEBUG_REQ(D_HA, req, "waking (set %p):", req->rq_set);
 291                         wake_up(&req->rq_set->set_waitq);
 292                 } else {
 293                         DEBUG_REQ(D_HA, req, "waking:");
 294                         wake_up(&req->rq_wait_for_rep);
 295                 }
 296         }
 297         spin_unlock_irqrestore(&imp->imp_lock, flags);
 298 }
 299
 300 inline void ptlrpc_invalidate_import_state(struct obd_import *imp)
 301 {
 302         struct ldlm_namespace *ns = imp->imp_obd->obd_namespace;
 303         if (ptlrpc_ldlm_namespace_cleanup == NULL)
 304                 CERROR("ptlrpc/ldlm hook is NULL!  Please tell phil\n");
 305         else
 306                 ptlrpc_ldlm_namespace_cleanup(ns, 1 /* no network ops */);
 307         ptlrpc_abort_inflight(imp);
 308 }
 309
 310 void ptlrpc_handle_failed_import(struct obd_import *imp)
 311 {
 312         ENTRY;
 313         if (!imp->imp_replayable) {
 314                 CDEBUG(D_HA,
 315                        "import %s@%s for %s not replayable, deactivating\n",
 316                        imp->imp_target_uuid.uuid,
 317                        imp->imp_connection->c_remote_uuid.uuid,
 318                        imp->imp_obd->obd_name);
 319                 ptlrpc_set_import_active(imp, 0);
 320         }
 321
 322         ptlrpc_run_failed_import_upcall(imp);
 323         EXIT;
 324 }
 325
 326 void ptlrpc_request_handle_eviction(struct ptlrpc_request *failed_req)
 327 {
 328         int rc;
 329         struct obd_import *imp= failed_req->rq_import;
 330         unsigned long flags;
 331         ENTRY;
 332
 333         CDEBUG(D_HA, "import %s of %s@%s evicted: reconnecting\n",
 334                imp->imp_obd->obd_name,
 335                imp->imp_target_uuid.uuid,
 336                imp->imp_connection->c_remote_uuid.uuid);
 337         rc = ptlrpc_recover_import(imp, NULL);
 338         if (rc) {
 339                 ptlrpc_resend_req(failed_req);
 340                 if (rc != -EALREADY)
 341                         ptlrpc_handle_failed_import(imp);
 342         } else {
 343                 LASSERT(failed_req->rq_import_generation < imp->imp_generation);
 344                 spin_lock_irqsave (&failed_req->rq_lock, flags);
 345                 failed_req->rq_err = 1;
 346                 spin_unlock_irqrestore (&failed_req->rq_lock, flags);
 347         }
 348         EXIT;
 349 }
 350
 351 int ptlrpc_set_import_active(struct obd_import *imp, int active)
 352 {
 353         struct obd_device *notify_obd;
 354         unsigned long flags;
 355         int rc;
 356
 357         LASSERT(imp->imp_obd);
 358
 359         notify_obd = imp->imp_obd->u.cli.cl_containing_lov;
 360
 361         /* When deactivating, mark import invalid, and abort in-flight
 362          * requests. */
 363         if (!active) {
 364                 spin_lock_irqsave(&imp->imp_lock, flags);
 365                 /* This is a bit of a hack, but invalidating replayable
 366                  * imports makes a temporary reconnect failure into a much more
 367                  * ugly -- and hard to remedy -- situation. */
 368                 if (!imp->imp_replayable) {
 369                         CDEBUG(D_HA, "setting import %s INVALID\n",
 370                                imp->imp_target_uuid.uuid);
 371                         imp->imp_invalid = 1;
 372                 }
 373                 imp->imp_generation++;
 374                 spin_unlock_irqrestore(&imp->imp_lock, flags);
 375                 ptlrpc_invalidate_import_state(imp);
 376                 //ptlrpc_abort_inflight(imp);
 377         }
 378
 379         if (notify_obd == NULL)
 380                 GOTO(out, rc = 0);
 381
 382         /* How gross is _this_? */
 383         if (!list_empty(&notify_obd->obd_exports)) {
 384                 struct lustre_handle fakeconn;
 385                 struct obd_ioctl_data ioc_data = { 0 };
 386                 struct obd_export *exp =
 387                         list_entry(notify_obd->obd_exports.next,
 388                                    struct obd_export, exp_obd_chain);
 389
 390                 fakeconn.cookie = exp->exp_handle.h_cookie;
 391                 ioc_data.ioc_inlbuf1 = (char *)&imp->imp_target_uuid;
 392                 ioc_data.ioc_offset = active;
 393                 rc = obd_iocontrol(IOC_LOV_SET_OSC_ACTIVE, &fakeconn,
 394                                    sizeof ioc_data, &ioc_data, NULL);
 395                 if (rc)
 396                         CERROR("error %sabling %s on LOV %p/%s: %d\n",
 397                                active ? "en" : "dis",
 398                                imp->imp_target_uuid.uuid, notify_obd,
 399                                notify_obd->obd_uuid.uuid, rc);
 400         } else {
 401                 CDEBUG(D_HA, "No exports for obd %p/%s, can't notify about "
 402                        "%p\n", notify_obd, notify_obd->obd_uuid.uuid,
 403                        imp->imp_obd->obd_uuid.uuid);
 404                 rc = -ENOENT;
 405         }
 406
 407 out:
 408         /* When activating, mark import valid */
 409         if (active && !rc) {
 410                 CDEBUG(D_HA, "setting import %s VALID\n",
 411                        imp->imp_target_uuid.uuid);
 412                 spin_lock_irqsave(&imp->imp_lock, flags);
 413                 imp->imp_invalid = 0;
 414                 spin_unlock_irqrestore(&imp->imp_lock, flags);
 415         }
 416
 417         RETURN(rc);
 418 }
 419
 420 void ptlrpc_fail_import(struct obd_import *imp, int generation)
 421 {
 422         unsigned long flags;
 423         int in_recovery = 0;
 424         ENTRY;
 425
 426         LASSERT (!imp->imp_dlm_fake);
 427
 428         spin_lock_irqsave(&imp->imp_lock, flags);
 429         if (imp->imp_level != LUSTRE_CONN_FULL)
 430                 in_recovery = 1;
 431         else
 432                 imp->imp_level = LUSTRE_CONN_NOTCONN;
 433         spin_unlock_irqrestore(&imp->imp_lock, flags);
 434
 435         if (in_recovery) {
 436                 EXIT;
 437                 return;
 438         }
 439
 440         ptlrpc_handle_failed_import(imp);
 441         EXIT;
 442 }
 443
 444 static int signal_completed_replay(struct obd_import *imp)
 445 {
 446         struct ptlrpc_request *req;
 447         int rc;
 448         ENTRY;
 449
 450         req = ptlrpc_prep_req(imp, OBD_PING, 0, NULL, NULL);
 451         if (!req)
 452                 RETURN(-ENOMEM);
 453
 454         req->rq_replen = lustre_msg_size(0, NULL);
 455         req->rq_level = LUSTRE_CONN_RECOVER;
 456         req->rq_reqmsg->flags |= MSG_LAST_REPLAY;
 457
 458         rc = ptlrpc_queue_wait(req);
 459
 460         ptlrpc_req_finished(req);
 461         RETURN(rc);
 462 }
 463
 464 int ptlrpc_recover_import(struct obd_import *imp, char *new_uuid)
 465 {
 466         int rc;
 467         unsigned long flags;
 468         int in_recover = 0;
 469         int recon_result;
 470         ENTRY;
 471
 472         spin_lock_irqsave(&imp->imp_lock, flags);
 473         if (imp->imp_level == LUSTRE_CONN_FULL ||
 474             imp->imp_level == LUSTRE_CONN_NOTCONN)
 475                     imp->imp_level = LUSTRE_CONN_RECOVER;
 476         else
 477                 in_recover = 1;
 478         spin_unlock_irqrestore(&imp->imp_lock, flags);
 479
 480         if (in_recover == 1)
 481                 RETURN(-EALREADY);
 482
 483         if (new_uuid) {
 484                 struct ptlrpc_connection *conn;
 485                 struct obd_uuid uuid;
 486                 struct ptlrpc_peer peer;
 487                 struct obd_export *dlmexp;
 488
 489                 obd_str2uuid(&uuid, new_uuid);
 490                 if (ptlrpc_uuid_to_peer(&uuid, &peer)) {
 491                         CERROR("no connection found for UUID %s\n", new_uuid);
 492                         RETURN(-EINVAL);
 493                 }
 494
 495                 conn = ptlrpc_get_connection(&peer, &uuid);
 496                 if (!conn)
 497                         RETURN(-ENOMEM);
 498
 499                 CDEBUG(D_HA, "switching import %s/%s from %s to %s\n",
 500                        imp->imp_target_uuid.uuid, imp->imp_obd->obd_name,
 501                        imp->imp_connection->c_remote_uuid.uuid,
 502                        conn->c_remote_uuid.uuid);
 503
 504                 /* Switch the import's connection and the DLM export's
 505                  * connection (which are almost certainly the same, but we
 506                  * keep distinct refs just to make things clearer. I think. */
 507                 if (imp->imp_connection)
 508                         ptlrpc_put_connection(imp->imp_connection);
 509                 /* We hand off the ref from ptlrpc_get_connection. */
 510                 imp->imp_connection = conn;
 511
 512                 dlmexp = class_conn2export(&imp->imp_dlm_handle);
 513                 if (dlmexp->exp_connection)
 514                         ptlrpc_put_connection(dlmexp->exp_connection);
 515                 dlmexp->exp_connection = ptlrpc_connection_addref(conn);
 516                 class_export_put(dlmexp);
 517
 518         }
 519
 520         recon_result = ptlrpc_reconnect_import(imp);
 521
 522         if (recon_result < 0) {
 523                 CERROR("failed to reconnect to %s@%s: %d\n",
 524                        imp->imp_target_uuid.uuid,
 525                        imp->imp_connection->c_remote_uuid.uuid, recon_result);
 526                 spin_lock_irqsave(&imp->imp_lock, flags);
 527                 imp->imp_level = LUSTRE_CONN_NOTCONN;
 528                 spin_unlock_irqrestore(&imp->imp_lock, flags);
 529                 RETURN(recon_result);
 530         }
 531
 532         if (recon_result == RECON_RESULT_RECOVERING) {
 533                 CDEBUG(D_HA, "replay requested by %s\n",
 534                        imp->imp_target_uuid.uuid);
 535                 rc = ptlrpc_replay(imp);
 536                 if (rc)
 537                         GOTO(out, rc);
 538
 539                 if (ptlrpc_ldlm_replay_locks == NULL)
 540                         CERROR("ptlrpc/ldlm hook is NULL!  Please tell phil\n");
 541                 else
 542                         rc = ptlrpc_ldlm_replay_locks(imp);
 543                 if (rc)
 544                         GOTO(out, rc);
 545
 546                 rc = signal_completed_replay(imp);
 547                 if (rc)
 548                         GOTO(out, rc);
 549         } else if (recon_result == RECON_RESULT_RECONNECTED) {
 550                 CDEBUG(D_HA, "reconnected to %s@%s\n",
 551                        imp->imp_target_uuid.uuid,
 552                        imp->imp_connection->c_remote_uuid.uuid);
 553         } else if (recon_result == RECON_RESULT_EVICTED) {
 554                 CDEBUG(D_HA, "evicted from %s@%s; invalidating\n",
 555                        imp->imp_target_uuid.uuid,
 556                        imp->imp_connection->c_remote_uuid.uuid);
 557                 ptlrpc_set_import_active(imp, 0);
 558 //                ptlrpc_invalidate_import_state(imp);
 559         } else {
 560                 LBUG();
 561         }
 562
 563         ptlrpc_set_import_active(imp, 1);
 564
 565         rc = ptlrpc_resend(imp);
 566
 567         spin_lock_irqsave(&imp->imp_lock, flags);
 568         imp->imp_level = LUSTRE_CONN_FULL;
 569         spin_unlock_irqrestore(&imp->imp_lock, flags);
 570
 571         ptlrpc_wake_delayed(imp);
 572         EXIT;
 573  out:
 574         return rc;
 575 }
 576
 577 void ptlrpc_fail_export(struct obd_export *exp)
 578 {
 579         int rc, already_failed;
 580         struct lustre_handle hdl;
 581         unsigned long flags;
 582
 583         spin_lock_irqsave(&exp->exp_lock, flags);
 584         already_failed = exp->exp_failed;
 585         exp->exp_failed = 1;
 586         spin_unlock_irqrestore(&exp->exp_lock, flags);
 587
 588         if (already_failed) {
 589                 CDEBUG(D_HA, "disconnecting dead export %p/%s; skipping\n",
 590                        exp, exp->exp_client_uuid.uuid);
 591                 return;
 592         }
 593
 594         CDEBUG(D_HA, "disconnecting export %p/%s\n",
 595                exp, exp->exp_client_uuid.uuid);
 596         hdl.cookie = exp->exp_handle.h_cookie;
 597         rc = obd_disconnect(&hdl, 0);
 598         if (rc)
 599                 CERROR("disconnecting export %p failed: %d\n", exp, rc);
 600 }