lustre/obdclass/genops.c

   1 /* -*- mode: c; c-basic-offset: 8; indent-tabs-mode: nil; -*-
   2  * vim:expandtab:shiftwidth=8:tabstop=8:
   3  *
   4  *  Copyright (c) 2001-2003 Cluster File Systems, Inc.
   5  *
   6  *   This file is part of the Lustre file system, http://www.lustre.org
   7  *   Lustre is a trademark of Cluster File Systems, Inc.
   8  *
   9  *   You may have signed or agreed to another license before downloading
  10  *   this software.  If so, you are bound by the terms and conditions
  11  *   of that agreement, and the following does not apply to you.  See the
  12  *   LICENSE file included with this distribution for more information.
  13  *
  14  *   If you did not agree to a different license, then this copy of Lustre
  15  *   is open source software; you can redistribute it and/or modify it
  16  *   under the terms of version 2 of the GNU General Public License as
  17  *   published by the Free Software Foundation.
  18  *
  19  *   In either case, Lustre is distributed in the hope that it will be
  20  *   useful, but WITHOUT ANY WARRANTY; without even the implied warranty
  21  *   of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  22  *   license text for more details.
  23  *
  24  * These are the only exported functions, they provide some generic
  25  * infrastructure for managing object devices
  26  */
  27
  28 #define DEBUG_SUBSYSTEM S_CLASS
  29 #ifndef __KERNEL__
  30 #include <liblustre.h>
  31 #endif
  32 #include <obd_ost.h>
  33 #include <obd_class.h>
  34 #include <lprocfs_status.h>
  35
  36 extern struct list_head obd_types;
  37 spinlock_t obd_types_lock;
  38
  39 cfs_mem_cache_t *obd_device_cachep;
  40 cfs_mem_cache_t *obdo_cachep;
  41 EXPORT_SYMBOL(obdo_cachep);
  42 cfs_mem_cache_t *import_cachep;
  43
  44 struct list_head  obd_zombie_imports;
  45 struct list_head  obd_zombie_exports;
  46 spinlock_t        obd_zombie_impexp_lock;
  47 void            (*obd_zombie_impexp_notify)(void) = NULL;
  48 EXPORT_SYMBOL(obd_zombie_impexp_notify);
  49
  50
  51 int (*ptlrpc_put_connection_superhack)(struct ptlrpc_connection *c);
  52
  53 /*
  54  * support functions: we could use inter-module communication, but this
  55  * is more portable to other OS's
  56  */
  57 static struct obd_device *obd_device_alloc(void)
  58 {
  59         struct obd_device *obd;
  60
  61         OBD_SLAB_ALLOC(obd, obd_device_cachep, SLAB_KERNEL, sizeof(*obd));
  62         if (obd != NULL) {
  63                 obd->obd_magic = OBD_DEVICE_MAGIC;
  64         }
  65         return obd;
  66 }
  67 EXPORT_SYMBOL(obd_device_alloc);
  68
  69 static void obd_device_free(struct obd_device *obd)
  70 {
  71         LASSERT(obd != NULL);
  72         LASSERTF(obd->obd_magic == OBD_DEVICE_MAGIC, "obd %p obd_magic %08x != %08x\n",
  73                  obd, obd->obd_magic, OBD_DEVICE_MAGIC);
  74         OBD_SLAB_FREE(obd, obd_device_cachep, sizeof(*obd));
  75 }
  76 EXPORT_SYMBOL(obd_device_free);
  77
  78 struct obd_type *class_search_type(const char *name)
  79 {
  80         struct list_head *tmp;
  81         struct obd_type *type;
  82
  83         spin_lock(&obd_types_lock);
  84         list_for_each(tmp, &obd_types) {
  85                 type = list_entry(tmp, struct obd_type, typ_chain);
  86                 if (strcmp(type->typ_name, name) == 0) {
  87                         spin_unlock(&obd_types_lock);
  88                         return type;
  89                 }
  90         }
  91         spin_unlock(&obd_types_lock);
  92         return NULL;
  93 }
  94
  95 struct obd_type *class_get_type(const char *name)
  96 {
  97         struct obd_type *type = class_search_type(name);
  98
  99 #ifdef CONFIG_KMOD
 100         if (!type) {
 101                 const char *modname = name;
 102                 if (strcmp(modname, LUSTRE_MDT_NAME) == 0)
 103                         modname = LUSTRE_MDS_NAME;
 104                 if (!request_module(modname)) {
 105                         CDEBUG(D_INFO, "Loaded module '%s'\n", modname);
 106                         type = class_search_type(name);
 107                 } else {
 108                         LCONSOLE_ERROR("Can't load module '%s'\n", modname);
 109                 }
 110         }
 111 #endif
 112         if (type) {
 113                 spin_lock(&type->obd_type_lock);
 114                 type->typ_refcnt++;
 115                 try_module_get(type->typ_ops->o_owner);
 116                 spin_unlock(&type->obd_type_lock);
 117         }
 118         return type;
 119 }
 120
 121 void class_put_type(struct obd_type *type)
 122 {
 123         LASSERT(type);
 124         spin_lock(&type->obd_type_lock);
 125         type->typ_refcnt--;
 126         module_put(type->typ_ops->o_owner);
 127         spin_unlock(&type->obd_type_lock);
 128 }
 129
 130 int class_register_type(struct obd_ops *ops, struct lprocfs_vars *vars,
 131                         const char *name)
 132 {
 133         struct obd_type *type;
 134         int rc = 0;
 135         ENTRY;
 136
 137         LASSERT(strnlen(name, 1024) < 1024);    /* sanity check */
 138
 139         if (class_search_type(name)) {
 140                 CDEBUG(D_IOCTL, "Type %s already registered\n", name);
 141                 RETURN(-EEXIST);
 142         }
 143
 144         rc = -ENOMEM;
 145         OBD_ALLOC(type, sizeof(*type));
 146         if (type == NULL)
 147                 RETURN(rc);
 148
 149         OBD_ALLOC(type->typ_ops, sizeof(*type->typ_ops));
 150         OBD_ALLOC(type->typ_name, strlen(name) + 1);
 151         if (type->typ_ops == NULL || type->typ_name == NULL)
 152                 GOTO (failed, rc);
 153
 154         *(type->typ_ops) = *ops;
 155         strcpy(type->typ_name, name);
 156         spin_lock_init(&type->obd_type_lock);
 157
 158 #ifdef LPROCFS
 159         type->typ_procroot = lprocfs_register(type->typ_name, proc_lustre_root,
 160                                               vars, type);
 161         if (IS_ERR(type->typ_procroot)) {
 162                 rc = PTR_ERR(type->typ_procroot);
 163                 type->typ_procroot = NULL;
 164                 GOTO (failed, rc);
 165         }
 166 #endif
 167
 168         spin_lock(&obd_types_lock);
 169         list_add(&type->typ_chain, &obd_types);
 170         spin_unlock(&obd_types_lock);
 171
 172         RETURN (0);
 173
 174  failed:
 175         if (type->typ_name != NULL)
 176                 OBD_FREE(type->typ_name, strlen(name) + 1);
 177         if (type->typ_ops != NULL)
 178                 OBD_FREE (type->typ_ops, sizeof (*type->typ_ops));
 179         OBD_FREE(type, sizeof(*type));
 180         RETURN(rc);
 181 }
 182
 183 int class_unregister_type(const char *name)
 184 {
 185         struct obd_type *type = class_search_type(name);
 186         ENTRY;
 187
 188         if (!type) {
 189                 CERROR("unknown obd type\n");
 190                 RETURN(-EINVAL);
 191         }
 192
 193         if (type->typ_refcnt) {
 194                 CERROR("type %s has refcount (%d)\n", name, type->typ_refcnt);
 195                 /* This is a bad situation, let's make the best of it */
 196                 /* Remove ops, but leave the name for debugging */
 197                 OBD_FREE(type->typ_ops, sizeof(*type->typ_ops));
 198                 RETURN(-EBUSY);
 199         }
 200
 201         if (type->typ_procroot)
 202                 lprocfs_remove(&type->typ_procroot);
 203
 204         spin_lock(&obd_types_lock);
 205         list_del(&type->typ_chain);
 206         spin_unlock(&obd_types_lock);
 207         OBD_FREE(type->typ_name, strlen(name) + 1);
 208         if (type->typ_ops != NULL)
 209                 OBD_FREE(type->typ_ops, sizeof(*type->typ_ops));
 210         OBD_FREE(type, sizeof(*type));
 211         RETURN(0);
 212 } /* class_unregister_type */
 213
 214 struct obd_device *class_newdev(const char *type_name, const char *name)
 215 {
 216         struct obd_device *result = NULL;
 217         struct obd_device *newdev;
 218         struct obd_type *type = NULL;
 219         int i;
 220         int new_obd_minor = 0;
 221
 222         if (strlen(name) > MAX_OBD_NAME) {
 223                 CERROR("name/uuid must be < %u bytes long\n", MAX_OBD_NAME);
 224                 RETURN(ERR_PTR(-EINVAL));
 225         }
 226
 227         type = class_get_type(type_name);
 228         if (type == NULL){
 229                 CERROR("OBD: unknown type: %s\n", type_name);
 230                 RETURN(ERR_PTR(-ENODEV));
 231         }
 232
 233         newdev = obd_device_alloc();
 234         if (newdev == NULL) {
 235                 class_put_type(type);
 236                 RETURN(ERR_PTR(-ENOMEM));
 237         }
 238         LASSERT(newdev->obd_magic == OBD_DEVICE_MAGIC);
 239
 240         spin_lock(&obd_dev_lock);
 241         for (i = 0; i < class_devno_max(); i++) {
 242                 struct obd_device *obd = class_num2obd(i);
 243                 if (obd && obd->obd_name && (strcmp(name, obd->obd_name) == 0)){
 244                         CERROR("Device %s already exists, won't add\n", name);
 245                         if (result) {
 246                                 LASSERTF(result->obd_magic == OBD_DEVICE_MAGIC,
 247                                          "%p obd_magic %08x != %08x\n", result,
 248                                          result->obd_magic, OBD_DEVICE_MAGIC);
 249                                 LASSERTF(result->obd_minor == new_obd_minor,
 250                                          "%p obd_minor %d != %d\n", result,
 251                                          result->obd_minor, new_obd_minor);
 252
 253                                 obd_devs[result->obd_minor] = NULL;
 254                                 result->obd_name[0]='\0';
 255                         }
 256                         result = ERR_PTR(-EEXIST);
 257                         break;
 258                 }
 259                 if (!result && !obd) {
 260                         result = newdev;
 261                         result->obd_minor = i;
 262                         new_obd_minor = i;
 263                         result->obd_type = type;
 264                         memcpy(result->obd_name, name, strlen(name));
 265                         obd_devs[i] = result;
 266                 }
 267         }
 268         spin_unlock(&obd_dev_lock);
 269
 270         if (result == NULL && i >= class_devno_max()) {
 271                 CERROR("all %u OBD devices used, increase MAX_OBD_DEVICES\n",
 272                        class_devno_max());
 273                 result = ERR_PTR(-EOVERFLOW);
 274         }
 275
 276         if (IS_ERR(result)) {
 277                 obd_device_free(newdev);
 278                 class_put_type(type);
 279         } else {
 280                 CDEBUG(D_IOCTL, "Adding new device %s (%p)\n",
 281                        result->obd_name, result);
 282         }
 283         return result;
 284 }
 285
 286 void class_release_dev(struct obd_device *obd)
 287 {
 288         struct obd_type *obd_type = obd->obd_type;
 289
 290         LASSERTF(obd->obd_magic == OBD_DEVICE_MAGIC, "%p obd_magic %08x != %08x\n",
 291                  obd, obd->obd_magic, OBD_DEVICE_MAGIC);
 292         LASSERTF(obd == obd_devs[obd->obd_minor], "obd %p != obd_devs[%d] %p\n",
 293                  obd, obd->obd_minor, obd_devs[obd->obd_minor]);
 294         LASSERT(obd_type != NULL);
 295
 296         CDEBUG(D_INFO, "Release obd device %s obd_type name =%s\n",
 297                obd->obd_name,obd->obd_type->typ_name);
 298
 299         spin_lock(&obd_dev_lock);
 300         obd_devs[obd->obd_minor] = NULL;
 301         spin_unlock(&obd_dev_lock);
 302         obd_device_free(obd);
 303
 304         class_put_type(obd_type);
 305 }
 306
 307 int class_name2dev(const char *name)
 308 {
 309         int i;
 310
 311         if (!name)
 312                 return -1;
 313
 314         spin_lock(&obd_dev_lock);
 315         for (i = 0; i < class_devno_max(); i++) {
 316                 struct obd_device *obd = class_num2obd(i);
 317                 if (obd && obd->obd_name && strcmp(name, obd->obd_name) == 0) {
 318                         /* Make sure we finished attaching before we give
 319                            out any references */
 320                         LASSERT(obd->obd_magic == OBD_DEVICE_MAGIC);
 321                         if (obd->obd_attached) {
 322                                 spin_unlock(&obd_dev_lock);
 323                                 return i;
 324                         }
 325                         break;
 326                 }
 327         }
 328         spin_unlock(&obd_dev_lock);
 329
 330         return -1;
 331 }
 332
 333 struct obd_device *class_name2obd(const char *name)
 334 {
 335         int dev = class_name2dev(name);
 336
 337         if (dev < 0 || dev > class_devno_max())
 338                 return NULL;
 339         return class_num2obd(dev);
 340 }
 341
 342 int class_uuid2dev(struct obd_uuid *uuid)
 343 {
 344         int i;
 345
 346         spin_lock(&obd_dev_lock);
 347         for (i = 0; i < class_devno_max(); i++) {
 348                 struct obd_device *obd = class_num2obd(i);
 349                 if (obd && obd_uuid_equals(uuid, &obd->obd_uuid)) {
 350                         LASSERT(obd->obd_magic == OBD_DEVICE_MAGIC);
 351                         spin_unlock(&obd_dev_lock);
 352                         return i;
 353                 }
 354         }
 355         spin_unlock(&obd_dev_lock);
 356
 357         return -1;
 358 }
 359
 360 struct obd_device *class_uuid2obd(struct obd_uuid *uuid)
 361 {
 362         int dev = class_uuid2dev(uuid);
 363         if (dev < 0)
 364                 return NULL;
 365         return class_num2obd(dev);
 366 }
 367
 368 struct obd_device *class_num2obd(int num)
 369 {
 370         struct obd_device *obd = NULL;
 371
 372         if (num < class_devno_max()) {
 373                 obd = obd_devs[num];
 374                 if (obd == NULL) {
 375                         return NULL;
 376                 }
 377
 378                 LASSERTF(obd->obd_magic == OBD_DEVICE_MAGIC,
 379                          "%p obd_magic %08x != %08x\n",
 380                          obd, obd->obd_magic, OBD_DEVICE_MAGIC);
 381                 LASSERTF(obd->obd_minor == num,
 382                          "%p obd_minor %0d != %0d\n",
 383                          obd, obd->obd_minor, num);
 384         }
 385
 386         return obd;
 387 }
 388
 389 void class_obd_list(void)
 390 {
 391         char *status;
 392         int i;
 393
 394         spin_lock(&obd_dev_lock);
 395         for (i = 0; i < class_devno_max(); i++) {
 396                 struct obd_device *obd = class_num2obd(i);
 397                 if (obd == NULL)
 398                         continue;
 399                 if (obd->obd_stopping)
 400                         status = "ST";
 401                 else if (obd->obd_set_up)
 402                         status = "UP";
 403                 else if (obd->obd_attached)
 404                         status = "AT";
 405                 else
 406                         status = "--";
 407                 LCONSOLE(D_CONFIG, "%3d %s %s %s %s %d\n",
 408                          i, status, obd->obd_type->typ_name,
 409                          obd->obd_name, obd->obd_uuid.uuid,
 410                          atomic_read(&obd->obd_refcount));
 411         }
 412         spin_unlock(&obd_dev_lock);
 413         return;
 414 }
 415
 416 /* Search for a client OBD connected to tgt_uuid.  If grp_uuid is
 417    specified, then only the client with that uuid is returned,
 418    otherwise any client connected to the tgt is returned. */
 419 struct obd_device * class_find_client_obd(struct obd_uuid *tgt_uuid,
 420                                           const char * typ_name,
 421                                           struct obd_uuid *grp_uuid)
 422 {
 423         int i;
 424
 425         spin_lock(&obd_dev_lock);
 426         for (i = 0; i < class_devno_max(); i++) {
 427                 struct obd_device *obd = class_num2obd(i);
 428                 if (obd == NULL)
 429                         continue;
 430                 if ((strncmp(obd->obd_type->typ_name, typ_name,
 431                              strlen(typ_name)) == 0)) {
 432                         if (obd_uuid_equals(tgt_uuid,
 433                                             &obd->u.cli.cl_target_uuid) &&
 434                             ((grp_uuid)? obd_uuid_equals(grp_uuid,
 435                                                          &obd->obd_uuid) : 1)) {
 436                                 spin_unlock(&obd_dev_lock);
 437                                 return obd;
 438                         }
 439                 }
 440         }
 441         spin_unlock(&obd_dev_lock);
 442
 443         return NULL;
 444 }
 445
 446 struct obd_device *class_find_client_notype(struct obd_uuid *tgt_uuid,
 447                                             struct obd_uuid *grp_uuid)
 448 {
 449         struct obd_device *obd;
 450
 451         obd = class_find_client_obd(tgt_uuid, LUSTRE_MDC_NAME, NULL);
 452         if (!obd)
 453                 obd = class_find_client_obd(tgt_uuid, LUSTRE_OSC_NAME,
 454                                             grp_uuid);
 455         return obd;
 456 }
 457
 458 /* Iterate the obd_device list looking devices have grp_uuid. Start
 459    searching at *next, and if a device is found, the next index to look
 460    at is saved in *next. If next is NULL, then the first matching device
 461    will always be returned. */
 462 struct obd_device * class_devices_in_group(struct obd_uuid *grp_uuid, int *next)
 463 {
 464         int i;
 465
 466         if (next == NULL)
 467                 i = 0;
 468         else if (*next >= 0 && *next < class_devno_max())
 469                 i = *next;
 470         else
 471                 return NULL;
 472
 473         spin_lock(&obd_dev_lock);
 474         for (; i < class_devno_max(); i++) {
 475                 struct obd_device *obd = class_num2obd(i);
 476                 if (obd == NULL)
 477                         continue;
 478                 if (obd_uuid_equals(grp_uuid, &obd->obd_uuid)) {
 479                         if (next != NULL)
 480                                 *next = i+1;
 481                         spin_unlock(&obd_dev_lock);
 482                         return obd;
 483                 }
 484         }
 485         spin_unlock(&obd_dev_lock);
 486
 487         return NULL;
 488 }
 489
 490
 491 void obd_cleanup_caches(void)
 492 {
 493         int rc;
 494
 495         ENTRY;
 496         if (obd_device_cachep) {
 497                 rc = cfs_mem_cache_destroy(obd_device_cachep);
 498                 LASSERTF(rc == 0, "Cannot destropy ll_obd_device_cache: rc %d\n", rc);
 499                 obd_device_cachep = NULL;
 500         }
 501         if (obdo_cachep) {
 502                 rc = cfs_mem_cache_destroy(obdo_cachep);
 503                 LASSERTF(rc == 0, "Cannot destory ll_obdo_cache\n");
 504                 obdo_cachep = NULL;
 505         }
 506         if (import_cachep) {
 507                 rc = cfs_mem_cache_destroy(import_cachep);
 508                 LASSERTF(rc == 0, "Cannot destory ll_import_cache\n");
 509                 import_cachep = NULL;
 510         }
 511         EXIT;
 512 }
 513
 514 int obd_init_caches(void)
 515 {
 516         ENTRY;
 517
 518         LASSERT(obd_device_cachep == NULL);
 519         obd_device_cachep = cfs_mem_cache_create("ll_obd_dev_cache",
 520                                               sizeof(struct obd_device), 0, 0);
 521         if (!obd_device_cachep)
 522                 GOTO(out, -ENOMEM);
 523
 524         LASSERT(obdo_cachep == NULL);
 525         obdo_cachep = cfs_mem_cache_create("ll_obdo_cache", sizeof(struct obdo),
 526                                         0, 0);
 527         if (!obdo_cachep)
 528                 GOTO(out, -ENOMEM);
 529
 530         LASSERT(import_cachep == NULL);
 531         import_cachep = cfs_mem_cache_create("ll_import_cache",
 532                                           sizeof(struct obd_import),
 533                                           0, 0);
 534         if (!import_cachep)
 535                 GOTO(out, -ENOMEM);
 536
 537         RETURN(0);
 538  out:
 539         obd_cleanup_caches();
 540         RETURN(-ENOMEM);
 541
 542 }
 543
 544 /* map connection to client */
 545 struct obd_export *class_conn2export(struct lustre_handle *conn)
 546 {
 547         struct obd_export *export;
 548         ENTRY;
 549
 550         if (!conn) {
 551                 CDEBUG(D_CACHE, "looking for null handle\n");
 552                 RETURN(NULL);
 553         }
 554
 555         if (conn->cookie == -1) {  /* this means assign a new connection */
 556                 CDEBUG(D_CACHE, "want a new connection\n");
 557                 RETURN(NULL);
 558         }
 559
 560         CDEBUG(D_INFO, "looking for export cookie "LPX64"\n", conn->cookie);
 561         export = class_handle2object(conn->cookie);
 562         RETURN(export);
 563 }
 564
 565 struct obd_device *class_exp2obd(struct obd_export *exp)
 566 {
 567         if (exp)
 568                 return exp->exp_obd;
 569         return NULL;
 570 }
 571
 572 struct obd_device *class_conn2obd(struct lustre_handle *conn)
 573 {
 574         struct obd_export *export;
 575         export = class_conn2export(conn);
 576         if (export) {
 577                 struct obd_device *obd = export->exp_obd;
 578                 class_export_put(export);
 579                 return obd;
 580         }
 581         return NULL;
 582 }
 583
 584 struct obd_import *class_exp2cliimp(struct obd_export *exp)
 585 {
 586         struct obd_device *obd = exp->exp_obd;
 587         if (obd == NULL)
 588                 return NULL;
 589         return obd->u.cli.cl_import;
 590 }
 591
 592 struct obd_import *class_conn2cliimp(struct lustre_handle *conn)
 593 {
 594         struct obd_device *obd = class_conn2obd(conn);
 595         if (obd == NULL)
 596                 return NULL;
 597         return obd->u.cli.cl_import;
 598 }
 599
 600 /* Export management functions */
 601 static void export_handle_addref(void *export)
 602 {
 603         class_export_get(export);
 604 }
 605
 606 void __class_export_put(struct obd_export *exp)
 607 {
 608         if (atomic_dec_and_test(&exp->exp_refcount)) {
 609                 LASSERT (list_empty(&exp->exp_obd_chain));
 610
 611                 CDEBUG(D_IOCTL, "final put %p/%s\n",
 612                        exp, exp->exp_client_uuid.uuid);
 613
 614                 spin_lock(&obd_zombie_impexp_lock);
 615                 list_add(&exp->exp_obd_chain, &obd_zombie_exports);
 616                 spin_unlock(&obd_zombie_impexp_lock);
 617
 618                 if (obd_zombie_impexp_notify != NULL)
 619                         obd_zombie_impexp_notify();
 620         }
 621 }
 622 EXPORT_SYMBOL(__class_export_put);
 623
 624 void class_export_destroy(struct obd_export *exp)
 625 {
 626         struct obd_device *obd = exp->exp_obd;
 627
 628         LASSERT (atomic_read(&exp->exp_refcount) == 0);
 629
 630         CDEBUG(D_IOCTL, "destroying export %p/%s\n", exp,
 631                exp->exp_client_uuid.uuid);
 632
 633         LASSERT(obd != NULL);
 634
 635         /* "Local" exports (lctl, LOV->{mdc,osc}) have no connection. */
 636         if (exp->exp_connection)
 637                 ptlrpc_put_connection_superhack(exp->exp_connection);
 638
 639         LASSERT(list_empty(&exp->exp_outstanding_replies));
 640         LASSERT(list_empty(&exp->exp_handle.h_link));
 641         obd_destroy_export(exp);
 642
 643         OBD_FREE(exp, sizeof(*exp));
 644         class_decref(obd);
 645 }
 646
 647 /* Creates a new export, adds it to the hash table, and returns a
 648  * pointer to it. The refcount is 2: one for the hash reference, and
 649  * one for the pointer returned by this function. */
 650 struct obd_export *class_new_export(struct obd_device *obd,
 651                                     struct obd_uuid *cluuid)
 652 {
 653         struct obd_export *export, *tmp;
 654
 655         OBD_ALLOC(export, sizeof(*export));
 656         if (!export)
 657                 return ERR_PTR(-ENOMEM);
 658
 659         export->exp_conn_cnt = 0;
 660         atomic_set(&export->exp_refcount, 2);
 661         atomic_set(&export->exp_rpc_count, 0);
 662         export->exp_obd = obd;
 663         CFS_INIT_LIST_HEAD(&export->exp_outstanding_replies);
 664         /* XXX this should be in LDLM init */
 665         CFS_INIT_LIST_HEAD(&export->exp_ldlm_data.led_held_locks);
 666         spin_lock_init(&export->exp_ldlm_data.led_lock);
 667
 668         CFS_INIT_LIST_HEAD(&export->exp_handle.h_link);
 669         class_handle_hash(&export->exp_handle, export_handle_addref);
 670         export->exp_last_request_time = CURRENT_SECONDS;
 671         spin_lock_init(&export->exp_lock);
 672
 673         export->exp_client_uuid = *cluuid;
 674         obd_init_export(export);
 675
 676         spin_lock(&obd->obd_dev_lock);
 677         if (!obd_uuid_equals(cluuid, &obd->obd_uuid)) {
 678                 list_for_each_entry(tmp, &obd->obd_exports, exp_obd_chain) {
 679                         if (obd_uuid_equals(cluuid, &tmp->exp_client_uuid)) {
 680                                 spin_unlock(&obd->obd_dev_lock);
 681                                 CWARN("%s: denying duplicate export for %s\n",
 682                                       obd->obd_name, cluuid->uuid);
 683                                 class_handle_unhash(&export->exp_handle);
 684                                 OBD_FREE_PTR(export);
 685                                 return ERR_PTR(-EALREADY);
 686                         }
 687                 }
 688         }
 689         LASSERT(!obd->obd_stopping); /* shouldn't happen, but might race */
 690         class_incref(obd);
 691         list_add(&export->exp_obd_chain, &export->exp_obd->obd_exports);
 692         list_add_tail(&export->exp_obd_chain_timed,
 693                       &export->exp_obd->obd_exports_timed);
 694         export->exp_obd->obd_num_exports++;
 695         spin_unlock(&obd->obd_dev_lock);
 696
 697         return export;
 698 }
 699 EXPORT_SYMBOL(class_new_export);
 700
 701 void class_unlink_export(struct obd_export *exp)
 702 {
 703         class_handle_unhash(&exp->exp_handle);
 704
 705         spin_lock(&exp->exp_obd->obd_dev_lock);
 706         list_del_init(&exp->exp_obd_chain);
 707         list_del_init(&exp->exp_obd_chain_timed);
 708         exp->exp_obd->obd_num_exports--;
 709         spin_unlock(&exp->exp_obd->obd_dev_lock);
 710
 711         class_export_put(exp);
 712 }
 713 EXPORT_SYMBOL(class_unlink_export);
 714
 715 /* Import management functions */
 716 static void import_handle_addref(void *import)
 717 {
 718         class_import_get(import);
 719 }
 720
 721 struct obd_import *class_import_get(struct obd_import *import)
 722 {
 723         LASSERT(atomic_read(&import->imp_refcount) >= 0);
 724         LASSERT(atomic_read(&import->imp_refcount) < 0x5a5a5a);
 725         atomic_inc(&import->imp_refcount);
 726         CDEBUG(D_INFO, "import %p refcount=%d\n", import,
 727                atomic_read(&import->imp_refcount));
 728         return import;
 729 }
 730 EXPORT_SYMBOL(class_import_get);
 731
 732 void class_import_put(struct obd_import *import)
 733 {
 734         ENTRY;
 735
 736         CDEBUG(D_INFO, "import %p refcount=%d\n", import,
 737                atomic_read(&import->imp_refcount) - 1);
 738
 739         LASSERT(atomic_read(&import->imp_refcount) > 0);
 740         LASSERT(atomic_read(&import->imp_refcount) < 0x5a5a5a);
 741         LASSERT(list_empty(&import->imp_zombie_chain));
 742
 743         if (atomic_dec_and_test(&import->imp_refcount)) {
 744
 745                 CDEBUG(D_INFO, "final put import %p\n", import);
 746
 747                 spin_lock(&obd_zombie_impexp_lock);
 748                 list_add(&import->imp_zombie_chain, &obd_zombie_imports);
 749                 spin_unlock(&obd_zombie_impexp_lock);
 750
 751                 if (obd_zombie_impexp_notify != NULL)
 752                         obd_zombie_impexp_notify();
 753         }
 754
 755         EXIT;
 756 }
 757
 758 void class_import_destroy(struct obd_import *import)
 759 {
 760         ENTRY;
 761
 762         CDEBUG(D_IOCTL, "destroying import %p\n", import);
 763
 764         LASSERT(atomic_read(&import->imp_refcount) == 0);
 765
 766         ptlrpc_put_connection_superhack(import->imp_connection);
 767
 768         while (!list_empty(&import->imp_conn_list)) {
 769                 struct obd_import_conn *imp_conn;
 770
 771                 imp_conn = list_entry(import->imp_conn_list.next,
 772                                       struct obd_import_conn, oic_item);
 773                 list_del(&imp_conn->oic_item);
 774                 ptlrpc_put_connection_superhack(imp_conn->oic_conn);
 775                 OBD_FREE(imp_conn, sizeof(*imp_conn));
 776         }
 777
 778         LASSERT(list_empty(&import->imp_handle.h_link));
 779         class_decref(import->imp_obd);
 780         OBD_FREE(import, sizeof(*import));
 781
 782         EXIT;
 783 }
 784 EXPORT_SYMBOL(class_import_put);
 785
 786 struct obd_import *class_new_import(struct obd_device *obd)
 787 {
 788         struct obd_import *imp;
 789
 790         OBD_ALLOC(imp, sizeof(*imp));
 791         if (imp == NULL)
 792                 return NULL;
 793
 794         CFS_INIT_LIST_HEAD(&imp->imp_zombie_chain);
 795         CFS_INIT_LIST_HEAD(&imp->imp_replay_list);
 796         CFS_INIT_LIST_HEAD(&imp->imp_sending_list);
 797         CFS_INIT_LIST_HEAD(&imp->imp_delayed_list);
 798         spin_lock_init(&imp->imp_lock);
 799         imp->imp_last_success_conn = 0;
 800         imp->imp_state = LUSTRE_IMP_NEW;
 801         imp->imp_obd = class_incref(obd);
 802         cfs_waitq_init(&imp->imp_recovery_waitq);
 803
 804         atomic_set(&imp->imp_refcount, 2);
 805         atomic_set(&imp->imp_inflight, 0);
 806         atomic_set(&imp->imp_replay_inflight, 0);
 807         CFS_INIT_LIST_HEAD(&imp->imp_conn_list);
 808         CFS_INIT_LIST_HEAD(&imp->imp_handle.h_link);
 809         class_handle_hash(&imp->imp_handle, import_handle_addref);
 810
 811         /* the default magic is V1, will be used in connect RPC, and
 812          * then adjusted according to the flags in request/reply. */
 813         imp->imp_msg_magic = LUSTRE_MSG_MAGIC_V1;
 814
 815         return imp;
 816 }
 817 EXPORT_SYMBOL(class_new_import);
 818
 819 void class_destroy_import(struct obd_import *import)
 820 {
 821         LASSERT(import != NULL);
 822         LASSERT(import != LP_POISON);
 823
 824         class_handle_unhash(&import->imp_handle);
 825
 826         import->imp_generation++;
 827         class_import_put(import);
 828 }
 829 EXPORT_SYMBOL(class_destroy_import);
 830
 831 /* A connection defines an export context in which preallocation can
 832    be managed. This releases the export pointer reference, and returns
 833    the export handle, so the export refcount is 1 when this function
 834    returns. */
 835 int class_connect(struct lustre_handle *conn, struct obd_device *obd,
 836                   struct obd_uuid *cluuid)
 837 {
 838         struct obd_export *export;
 839         LASSERT(conn != NULL);
 840         LASSERT(obd != NULL);
 841         LASSERT(cluuid != NULL);
 842         ENTRY;
 843
 844         export = class_new_export(obd, cluuid);
 845         if (IS_ERR(export))
 846                 RETURN(PTR_ERR(export));
 847
 848         conn->cookie = export->exp_handle.h_cookie;
 849         class_export_put(export);
 850
 851         CDEBUG(D_IOCTL, "connect: client %s, cookie "LPX64"\n",
 852                cluuid->uuid, conn->cookie);
 853         RETURN(0);
 854 }
 855 EXPORT_SYMBOL(class_connect);
 856
 857 /* This function removes two references from the export: one for the
 858  * hash entry and one for the export pointer passed in.  The export
 859  * pointer passed to this function is destroyed should not be used
 860  * again. */
 861 int class_disconnect(struct obd_export *export)
 862 {
 863         int already_disconnected;
 864         ENTRY;
 865
 866         if (export == NULL) {
 867                 fixme();
 868                 CDEBUG(D_IOCTL, "attempting to free NULL export %p\n", export);
 869                 RETURN(-EINVAL);
 870         }
 871
 872         spin_lock(&export->exp_lock);
 873         already_disconnected = export->exp_disconnected;
 874         export->exp_disconnected = 1;
 875         spin_unlock(&export->exp_lock);
 876
 877         /* class_cleanup(), abort_recovery(), and class_fail_export()
 878          * all end up in here, and if any of them race we shouldn't
 879          * call extra class_export_puts(). */
 880         if (already_disconnected)
 881                 RETURN(0);
 882
 883         CDEBUG(D_IOCTL, "disconnect: cookie "LPX64"\n",
 884                export->exp_handle.h_cookie);
 885
 886         class_unlink_export(export);
 887         class_export_put(export);
 888         RETURN(0);
 889 }
 890
 891 static void class_disconnect_export_list(struct list_head *list, int flags)
 892 {
 893         int rc;
 894         struct lustre_handle fake_conn;
 895         struct obd_export *fake_exp, *exp;
 896         ENTRY;
 897
 898         /* It's possible that an export may disconnect itself, but
 899          * nothing else will be added to this list. */
 900         while (!list_empty(list)) {
 901                 exp = list_entry(list->next, struct obd_export, exp_obd_chain);
 902                 class_export_get(exp);
 903                 exp->exp_flags = flags;
 904
 905                 if (obd_uuid_equals(&exp->exp_client_uuid,
 906                                     &exp->exp_obd->obd_uuid)) {
 907                         CDEBUG(D_HA,
 908                                "exp %p export uuid == obd uuid, don't discon\n",
 909                                exp);
 910                         /* Need to delete this now so we don't end up pointing
 911                          * to work_list later when this export is cleaned up. */
 912                         list_del_init(&exp->exp_obd_chain);
 913                         class_export_put(exp);
 914                         continue;
 915                 }
 916
 917                 fake_conn.cookie = exp->exp_handle.h_cookie;
 918                 fake_exp = class_conn2export(&fake_conn);
 919                 if (!fake_exp) {
 920                         class_export_put(exp);
 921                         continue;
 922                 }
 923                 fake_exp->exp_flags = flags;
 924                 rc = obd_disconnect(fake_exp);
 925                 class_export_put(exp);
 926                 if (rc) {
 927                         CDEBUG(D_HA, "disconnecting export %p failed: %d\n",
 928                                exp, rc);
 929                 } else {
 930                         CDEBUG(D_HA, "export %p disconnected\n", exp);
 931                 }
 932         }
 933         EXIT;
 934 }
 935
 936 static inline int get_exp_flags_from_obd(struct obd_device *obd)
 937 {
 938         return ((obd->obd_fail ? OBD_OPT_FAILOVER : 0) |
 939                 (obd->obd_force ? OBD_OPT_FORCE : 0));
 940 }
 941
 942 void class_disconnect_exports(struct obd_device *obd)
 943 {
 944         struct list_head work_list;
 945         ENTRY;
 946
 947         /* Move all of the exports from obd_exports to a work list, en masse. */
 948         spin_lock(&obd->obd_dev_lock);
 949         list_add(&work_list, &obd->obd_exports);
 950         list_del_init(&obd->obd_exports);
 951         spin_unlock(&obd->obd_dev_lock);
 952
 953         CDEBUG(D_HA, "OBD device %d (%p) has exports, "
 954                "disconnecting them\n", obd->obd_minor, obd);
 955         class_disconnect_export_list(&work_list, get_exp_flags_from_obd(obd));
 956         EXIT;
 957 }
 958 EXPORT_SYMBOL(class_disconnect_exports);
 959
 960 /* Remove exports that have not completed recovery.
 961  */
 962 void class_disconnect_stale_exports(struct obd_device *obd)
 963 {
 964         struct list_head work_list;
 965         struct list_head *pos, *n;
 966         struct obd_export *exp;
 967         int cnt = 0;
 968         ENTRY;
 969
 970         CFS_INIT_LIST_HEAD(&work_list);
 971         spin_lock(&obd->obd_dev_lock);
 972         list_for_each_safe(pos, n, &obd->obd_exports) {
 973                 exp = list_entry(pos, struct obd_export, exp_obd_chain);
 974                 if (exp->exp_replay_needed) {
 975                         list_del(&exp->exp_obd_chain);
 976                         list_add(&exp->exp_obd_chain, &work_list);
 977                         cnt++;
 978                 }
 979         }
 980         spin_unlock(&obd->obd_dev_lock);
 981
 982         CDEBUG(D_ERROR, "%s: disconnecting %d stale clients\n",
 983                obd->obd_name, cnt);
 984         class_disconnect_export_list(&work_list, get_exp_flags_from_obd(obd));
 985         EXIT;
 986 }
 987 EXPORT_SYMBOL(class_disconnect_stale_exports);
 988
 989 int oig_init(struct obd_io_group **oig_out)
 990 {
 991         struct obd_io_group *oig;
 992         ENTRY;
 993
 994         OBD_ALLOC(oig, sizeof(*oig));
 995         if (oig == NULL)
 996                 RETURN(-ENOMEM);
 997
 998         spin_lock_init(&oig->oig_lock);
 999         oig->oig_rc = 0;
1000         oig->oig_pending = 0;
1001         atomic_set(&oig->oig_refcount, 1);
1002         cfs_waitq_init(&oig->oig_waitq);
1003         CFS_INIT_LIST_HEAD(&oig->oig_occ_list);
1004
1005         *oig_out = oig;
1006         RETURN(0);
1007 };
1008 EXPORT_SYMBOL(oig_init);
1009
1010 static inline void oig_grab(struct obd_io_group *oig)
1011 {
1012         atomic_inc(&oig->oig_refcount);
1013 }
1014
1015 void oig_release(struct obd_io_group *oig)
1016 {
1017         if (atomic_dec_and_test(&oig->oig_refcount))
1018                 OBD_FREE(oig, sizeof(*oig));
1019 }
1020 EXPORT_SYMBOL(oig_release);
1021
1022 int oig_add_one(struct obd_io_group *oig, struct oig_callback_context *occ)
1023 {
1024         int rc = 0;
1025         CDEBUG(D_CACHE, "oig %p ready to roll\n", oig);
1026         spin_lock(&oig->oig_lock);
1027         if (oig->oig_rc) {
1028                 rc = oig->oig_rc;
1029         } else {
1030                 oig->oig_pending++;
1031                 if (occ != NULL)
1032                         list_add_tail(&occ->occ_oig_item, &oig->oig_occ_list);
1033         }
1034         spin_unlock(&oig->oig_lock);
1035         oig_grab(oig);
1036
1037         return rc;
1038 }
1039 EXPORT_SYMBOL(oig_add_one);
1040
1041 void oig_complete_one(struct obd_io_group *oig,
1042                       struct oig_callback_context *occ, int rc)
1043 {
1044         cfs_waitq_t *wake = NULL;
1045         int old_rc;
1046
1047         spin_lock(&oig->oig_lock);
1048
1049         if (occ != NULL)
1050                 list_del_init(&occ->occ_oig_item);
1051
1052         old_rc = oig->oig_rc;
1053         if (oig->oig_rc == 0 && rc != 0)
1054                 oig->oig_rc = rc;
1055
1056         if (--oig->oig_pending <= 0)
1057                 wake = &oig->oig_waitq;
1058
1059         spin_unlock(&oig->oig_lock);
1060
1061         CDEBUG(D_CACHE, "oig %p completed, rc %d -> %d via %d, %d now "
1062                         "pending (racey)\n", oig, old_rc, oig->oig_rc, rc,
1063                         oig->oig_pending);
1064         if (wake)
1065                 cfs_waitq_signal(wake);
1066         oig_release(oig);
1067 }
1068 EXPORT_SYMBOL(oig_complete_one);
1069
1070 static int oig_done(struct obd_io_group *oig)
1071 {
1072         int rc = 0;
1073         spin_lock(&oig->oig_lock);
1074         if (oig->oig_pending <= 0)
1075                 rc = 1;
1076         spin_unlock(&oig->oig_lock);
1077         return rc;
1078 }
1079
1080 static void interrupted_oig(void *data)
1081 {
1082         struct obd_io_group *oig = data;
1083         struct oig_callback_context *occ;
1084
1085         spin_lock(&oig->oig_lock);
1086         /* We need to restart the processing each time we drop the lock, as
1087          * it is possible other threads called oig_complete_one() to remove
1088          * an entry elsewhere in the list while we dropped lock.  We need to
1089          * drop the lock because osc_ap_completion() calls oig_complete_one()
1090          * which re-gets this lock ;-) as well as a lock ordering issue. */
1091 restart:
1092         list_for_each_entry(occ, &oig->oig_occ_list, occ_oig_item) {
1093                 if (occ->interrupted)
1094                         continue;
1095                 occ->interrupted = 1;
1096                 spin_unlock(&oig->oig_lock);
1097                 occ->occ_interrupted(occ);
1098                 spin_lock(&oig->oig_lock);
1099                 goto restart;
1100         }
1101         spin_unlock(&oig->oig_lock);
1102 }
1103
1104 int oig_wait(struct obd_io_group *oig)
1105 {
1106         struct l_wait_info lwi = LWI_INTR(interrupted_oig, oig);
1107         int rc;
1108
1109         CDEBUG(D_CACHE, "waiting for oig %p\n", oig);
1110
1111         do {
1112                 rc = l_wait_event(oig->oig_waitq, oig_done(oig), &lwi);
1113                 LASSERTF(rc == 0 || rc == -EINTR, "rc: %d\n", rc);
1114                 /* we can't continue until the oig has emptied and stopped
1115                  * referencing state that the caller will free upon return */
1116                 if (rc == -EINTR)
1117                         lwi = (struct l_wait_info){ 0, };
1118         } while (rc == -EINTR);
1119
1120         LASSERTF(oig->oig_pending == 0,
1121                  "exiting oig_wait(oig = %p) with %d pending\n", oig,
1122                  oig->oig_pending);
1123
1124         CDEBUG(D_CACHE, "done waiting on oig %p rc %d\n", oig, oig->oig_rc);
1125         return oig->oig_rc;
1126 }
1127 EXPORT_SYMBOL(oig_wait);
1128
1129 void class_fail_export(struct obd_export *exp)
1130 {
1131         int rc, already_failed;
1132
1133         spin_lock(&exp->exp_lock);
1134         already_failed = exp->exp_failed;
1135         exp->exp_failed = 1;
1136         spin_unlock(&exp->exp_lock);
1137
1138         if (already_failed) {
1139                 CDEBUG(D_HA, "disconnecting dead export %p/%s; skipping\n",
1140                        exp, exp->exp_client_uuid.uuid);
1141                 return;
1142         }
1143
1144         CDEBUG(D_HA, "disconnecting export %p/%s\n",
1145                exp, exp->exp_client_uuid.uuid);
1146
1147         if (obd_dump_on_timeout)
1148                 libcfs_debug_dumplog();
1149
1150         /* Most callers into obd_disconnect are removing their own reference
1151          * (request, for example) in addition to the one from the hash table.
1152          * We don't have such a reference here, so make one. */
1153         class_export_get(exp);
1154         rc = obd_disconnect(exp);
1155         if (rc)
1156                 CERROR("disconnecting export %p failed: %d\n", exp, rc);
1157         else
1158                 CDEBUG(D_HA, "disconnected export %p/%s\n",
1159                        exp, exp->exp_client_uuid.uuid);
1160 }
1161 EXPORT_SYMBOL(class_fail_export);
1162
1163 char *obd_export_nid2str(struct obd_export *exp)
1164 {
1165         if (exp->exp_connection != NULL)
1166                 return libcfs_nid2str(exp->exp_connection->c_peer.nid);
1167
1168         return "(no nid)";
1169 }
1170 EXPORT_SYMBOL(obd_export_nid2str);
1171
1172 #define EVICT_BATCH 32
1173 int obd_export_evict_by_nid(struct obd_device *obd, char *nid)
1174 {
1175         struct obd_export *doomed_exp[EVICT_BATCH] = { NULL };
1176         struct list_head *p;
1177         int exports_evicted = 0, num_to_evict = 0, i;
1178
1179 search_again:
1180         spin_lock(&obd->obd_dev_lock);
1181         list_for_each(p, &obd->obd_exports) {
1182                 doomed_exp[num_to_evict] = list_entry(p, struct obd_export,
1183                                                       exp_obd_chain);
1184                 if (strcmp(obd_export_nid2str(doomed_exp[num_to_evict]),
1185                            nid) == 0) {
1186                         class_export_get(doomed_exp[num_to_evict]);
1187                         if (++num_to_evict == EVICT_BATCH)
1188                                 break;
1189                 }
1190         }
1191         spin_unlock(&obd->obd_dev_lock);
1192
1193         for (i = 0; i < num_to_evict; i++) {
1194                 exports_evicted++;
1195                 CWARN("%s: evict NID '%s' (%s) #%d at adminstrative request\n",
1196                        obd->obd_name, nid, doomed_exp[i]->exp_client_uuid.uuid,
1197                        exports_evicted);
1198                 class_fail_export(doomed_exp[i]);
1199                 class_export_put(doomed_exp[i]);
1200         }
1201         if (num_to_evict == EVICT_BATCH) {
1202                 num_to_evict = 0;
1203                 goto search_again;
1204         }
1205
1206         if (!exports_evicted)
1207                 CDEBUG(D_HA,"%s: can't disconnect NID '%s': no exports found\n",
1208                        obd->obd_name, nid);
1209         return exports_evicted;
1210 }
1211 EXPORT_SYMBOL(obd_export_evict_by_nid);
1212
1213 int obd_export_evict_by_uuid(struct obd_device *obd, char *uuid)
1214 {
1215         struct obd_export *doomed_exp = NULL;
1216         struct list_head *p;
1217         struct obd_uuid doomed;
1218         int exports_evicted = 0;
1219
1220         obd_str2uuid(&doomed, uuid);
1221
1222         spin_lock(&obd->obd_dev_lock);
1223         list_for_each(p, &obd->obd_exports) {
1224                 doomed_exp = list_entry(p, struct obd_export, exp_obd_chain);
1225
1226                 if (obd_uuid_equals(&doomed, &doomed_exp->exp_client_uuid)) {
1227                         class_export_get(doomed_exp);
1228                         break;
1229                 }
1230                 doomed_exp = NULL;
1231         }
1232         spin_unlock(&obd->obd_dev_lock);
1233
1234         if (doomed_exp == NULL) {
1235                 CERROR("%s: can't disconnect %s: no exports found\n",
1236                        obd->obd_name, uuid);
1237         } else {
1238                 CWARN("%s: evicting %s at adminstrative request\n",
1239                        obd->obd_name, doomed_exp->exp_client_uuid.uuid);
1240                 class_fail_export(doomed_exp);
1241                 class_export_put(doomed_exp);
1242                 exports_evicted++;
1243         }
1244
1245         return exports_evicted;
1246 }
1247 EXPORT_SYMBOL(obd_export_evict_by_uuid);
1248
1249 void obd_zombie_impexp_cull(void)
1250 {
1251         struct obd_import *import;
1252         struct obd_export *export;
1253
1254         do {
1255                 spin_lock (&obd_zombie_impexp_lock);
1256
1257                 import = NULL;
1258                 if (!list_empty(&obd_zombie_imports)) {
1259                         import = list_entry(obd_zombie_imports.next,
1260                                             struct obd_import,
1261                                             imp_zombie_chain);
1262                         list_del(&import->imp_zombie_chain);
1263                 }
1264
1265                 export = NULL;
1266                 if (!list_empty(&obd_zombie_exports)) {
1267                         export = list_entry(obd_zombie_exports.next,
1268                                             struct obd_export,
1269                                             exp_obd_chain);
1270                         list_del_init(&export->exp_obd_chain);
1271                 }
1272
1273                 spin_unlock(&obd_zombie_impexp_lock);
1274
1275                 if (import != NULL)
1276                         class_import_destroy(import);
1277
1278                 if (export != NULL)
1279                         class_export_destroy(export);
1280
1281         } while (import != NULL || export != NULL);
1282 }
1283 EXPORT_SYMBOL(obd_zombie_impexp_cull);
1284
1285 void obd_zombie_impexp_init(void)
1286 {
1287         INIT_LIST_HEAD(&obd_zombie_imports);
1288         INIT_LIST_HEAD(&obd_zombie_exports);
1289         spin_lock_init(&obd_zombie_impexp_lock);
1290 }