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_type *type = NULL;
 218         int i;
 219         int new_obd_minor = 0;
 220
 221         if (strlen(name) > MAX_OBD_NAME) {
 222                 CERROR("name/uuid must be < %u bytes long\n", MAX_OBD_NAME);
 223                 RETURN(ERR_PTR(-EINVAL));
 224         }
 225
 226         type = class_get_type(type_name);
 227         if (type == NULL){
 228                 CERROR("OBD: unknown type: %s\n", type_name);
 229                 RETURN(ERR_PTR(-ENODEV));
 230         }
 231
 232         spin_lock(&obd_dev_lock);
 233         for (i = 0; i < class_devno_max(); i++) {
 234                 struct obd_device *obd = class_num2obd(i);
 235                 if (obd && obd->obd_name && (strcmp(name, obd->obd_name) == 0)){
 236                         CERROR("Device %s already exists, won't add\n", name);
 237                         if (result) {
 238                                 LASSERTF(result->obd_magic == OBD_DEVICE_MAGIC,
 239                                          "%p obd_magic %08x != %08x\n", result,
 240                                          result->obd_magic, OBD_DEVICE_MAGIC);
 241                                 LASSERTF(result->obd_minor == new_obd_minor,
 242                                          "%p obd_minor %d != %d\n", result,
 243                                          result->obd_minor, new_obd_minor);
 244
 245                                 obd_devs[result->obd_minor] = NULL;
 246                                 result->obd_name[0]='\0';
 247                                 obd_device_free(result);
 248                         }
 249                         result = ERR_PTR(-EEXIST);
 250                         break;
 251                 }
 252                 if (!result && !obd) {
 253                         obd = obd_device_alloc();
 254                         if (obd == NULL) {
 255                                result = ERR_PTR(-ENOMEM);
 256                                break;
 257                         }
 258
 259                         LASSERT(obd->obd_magic == OBD_DEVICE_MAGIC);
 260                         obd->obd_minor = i;
 261                         new_obd_minor = i;
 262                         obd->obd_type = type;
 263                         memcpy(obd->obd_name, name, strlen(name));
 264
 265                         result = obd;
 266                         obd_devs[i] = result;
 267                         obd = NULL;
 268                 }
 269         }
 270         spin_unlock(&obd_dev_lock);
 271
 272         if (result == NULL && i >= class_devno_max()) {
 273                 CERROR("all %u OBD devices used, increase MAX_OBD_DEVICES\n",
 274                        class_devno_max());
 275                 result = ERR_PTR(-EOVERFLOW);
 276         }
 277
 278         if (IS_ERR(result))
 279                 class_put_type(type);
 280         else
 281                 CDEBUG(D_IOCTL, "Adding new device %s (%p)\n",
 282                        result->obd_name, result);
 283
 284         return result;
 285 }
 286
 287 void class_release_dev(struct obd_device *obd)
 288 {
 289         struct obd_type *obd_type = obd->obd_type;
 290
 291         LASSERTF(obd->obd_magic == OBD_DEVICE_MAGIC, "%p obd_magic %08x != %08x\n",
 292                  obd, obd->obd_magic, OBD_DEVICE_MAGIC);
 293         LASSERTF(obd == obd_devs[obd->obd_minor], "obd %p != obd_devs[%d] %p\n",
 294                  obd, obd->obd_minor, obd_devs[obd->obd_minor]);
 295         LASSERT(obd_type != NULL);
 296
 297         CDEBUG(D_INFO, "Release obd device %s obd_type name =%s\n",
 298                obd->obd_name,obd->obd_type->typ_name);
 299
 300         spin_lock(&obd_dev_lock);
 301         obd_devs[obd->obd_minor] = NULL;
 302         obd_device_free(obd);
 303         spin_unlock(&obd_dev_lock);
 304
 305         class_put_type(obd_type);
 306 }
 307
 308 int class_name2dev(const char *name)
 309 {
 310         int i;
 311
 312         if (!name)
 313                 return -1;
 314
 315         spin_lock(&obd_dev_lock);
 316         for (i = 0; i < class_devno_max(); i++) {
 317                 struct obd_device *obd = class_num2obd(i);
 318                 if (obd && obd->obd_name && strcmp(name, obd->obd_name) == 0) {
 319                         /* Make sure we finished attaching before we give
 320                            out any references */
 321                         LASSERT(obd->obd_magic == OBD_DEVICE_MAGIC);
 322                         if (obd->obd_attached) {
 323                                 spin_unlock(&obd_dev_lock);
 324                                 return i;
 325                         }
 326                         break;
 327                 }
 328         }
 329         spin_unlock(&obd_dev_lock);
 330
 331         return -1;
 332 }
 333
 334 struct obd_device *class_name2obd(const char *name)
 335 {
 336         int dev = class_name2dev(name);
 337
 338         if (dev < 0 || dev > class_devno_max())
 339                 return NULL;
 340         return class_num2obd(dev);
 341 }
 342
 343 int class_uuid2dev(struct obd_uuid *uuid)
 344 {
 345         int i;
 346
 347         spin_lock(&obd_dev_lock);
 348         for (i = 0; i < class_devno_max(); i++) {
 349                 struct obd_device *obd = class_num2obd(i);
 350                 if (obd && obd_uuid_equals(uuid, &obd->obd_uuid)) {
 351                         LASSERT(obd->obd_magic == OBD_DEVICE_MAGIC);
 352                         spin_unlock(&obd_dev_lock);
 353                         return i;
 354                 }
 355         }
 356         spin_unlock(&obd_dev_lock);
 357
 358         return -1;
 359 }
 360
 361 struct obd_device *class_uuid2obd(struct obd_uuid *uuid)
 362 {
 363         int dev = class_uuid2dev(uuid);
 364         if (dev < 0)
 365                 return NULL;
 366         return class_num2obd(dev);
 367 }
 368
 369 struct obd_device *class_num2obd(int num)
 370 {
 371         struct obd_device *obd = NULL;
 372
 373         if (num < class_devno_max()) {
 374                 obd = obd_devs[num];
 375                 if (obd == NULL) {
 376                         return NULL;
 377                 }
 378
 379                 LASSERTF(obd->obd_magic == OBD_DEVICE_MAGIC,
 380                          "%p obd_magic %08x != %08x\n",
 381                          obd, obd->obd_magic, OBD_DEVICE_MAGIC);
 382                 LASSERTF(obd->obd_minor == num,
 383                          "%p obd_minor %0d != %0d\n",
 384                          obd, obd->obd_minor, num);
 385         }
 386
 387         return obd;
 388 }
 389
 390 void class_obd_list(void)
 391 {
 392         char *status;
 393         int i;
 394
 395         spin_lock(&obd_dev_lock);
 396         for (i = 0; i < class_devno_max(); i++) {
 397                 struct obd_device *obd = class_num2obd(i);
 398                 if (obd == NULL)
 399                         continue;
 400                 if (obd->obd_stopping)
 401                         status = "ST";
 402                 else if (obd->obd_set_up)
 403                         status = "UP";
 404                 else if (obd->obd_attached)
 405                         status = "AT";
 406                 else
 407                         status = "--";
 408                 LCONSOLE(D_CONFIG, "%3d %s %s %s %s %d\n",
 409                          i, status, obd->obd_type->typ_name,
 410                          obd->obd_name, obd->obd_uuid.uuid,
 411                          atomic_read(&obd->obd_refcount));
 412         }
 413         spin_unlock(&obd_dev_lock);
 414         return;
 415 }
 416
 417 /* Search for a client OBD connected to tgt_uuid.  If grp_uuid is
 418    specified, then only the client with that uuid is returned,
 419    otherwise any client connected to the tgt is returned. */
 420 struct obd_device * class_find_client_obd(struct obd_uuid *tgt_uuid,
 421                                           const char * typ_name,
 422                                           struct obd_uuid *grp_uuid)
 423 {
 424         int i;
 425
 426         spin_lock(&obd_dev_lock);
 427         for (i = 0; i < class_devno_max(); i++) {
 428                 struct obd_device *obd = class_num2obd(i);
 429                 if (obd == NULL)
 430                         continue;
 431                 if ((strncmp(obd->obd_type->typ_name, typ_name,
 432                              strlen(typ_name)) == 0)) {
 433                         if (obd_uuid_equals(tgt_uuid,
 434                                             &obd->u.cli.cl_target_uuid) &&
 435                             ((grp_uuid)? obd_uuid_equals(grp_uuid,
 436                                                          &obd->obd_uuid) : 1)) {
 437                                 spin_unlock(&obd_dev_lock);
 438                                 return obd;
 439                         }
 440                 }
 441         }
 442         spin_unlock(&obd_dev_lock);
 443
 444         return NULL;
 445 }
 446
 447 struct obd_device *class_find_client_notype(struct obd_uuid *tgt_uuid,
 448                                             struct obd_uuid *grp_uuid)
 449 {
 450         struct obd_device *obd;
 451
 452         obd = class_find_client_obd(tgt_uuid, LUSTRE_MDC_NAME, NULL);
 453         if (!obd)
 454                 obd = class_find_client_obd(tgt_uuid, LUSTRE_OSC_NAME,
 455                                             grp_uuid);
 456         return obd;
 457 }
 458
 459 /* Iterate the obd_device list looking devices have grp_uuid. Start
 460    searching at *next, and if a device is found, the next index to look
 461    at is saved in *next. If next is NULL, then the first matching device
 462    will always be returned. */
 463 struct obd_device * class_devices_in_group(struct obd_uuid *grp_uuid, int *next)
 464 {
 465         int i;
 466
 467         if (next == NULL)
 468                 i = 0;
 469         else if (*next >= 0 && *next < class_devno_max())
 470                 i = *next;
 471         else
 472                 return NULL;
 473
 474         spin_lock(&obd_dev_lock);
 475         for (; i < class_devno_max(); i++) {
 476                 struct obd_device *obd = class_num2obd(i);
 477                 if (obd == NULL)
 478                         continue;
 479                 if (obd_uuid_equals(grp_uuid, &obd->obd_uuid)) {
 480                         if (next != NULL)
 481                                 *next = i+1;
 482                         spin_unlock(&obd_dev_lock);
 483                         return obd;
 484                 }
 485         }
 486         spin_unlock(&obd_dev_lock);
 487
 488         return NULL;
 489 }
 490
 491
 492 void obd_cleanup_caches(void)
 493 {
 494         int rc;
 495
 496         ENTRY;
 497         if (obd_device_cachep) {
 498                 rc = cfs_mem_cache_destroy(obd_device_cachep);
 499                 LASSERTF(rc == 0, "Cannot destropy ll_obd_device_cache: rc %d\n", rc);
 500                 obd_device_cachep = NULL;
 501         }
 502         if (obdo_cachep) {
 503                 rc = cfs_mem_cache_destroy(obdo_cachep);
 504                 LASSERTF(rc == 0, "Cannot destory ll_obdo_cache\n");
 505                 obdo_cachep = NULL;
 506         }
 507         if (import_cachep) {
 508                 rc = cfs_mem_cache_destroy(import_cachep);
 509                 LASSERTF(rc == 0, "Cannot destory ll_import_cache\n");
 510                 import_cachep = NULL;
 511         }
 512         EXIT;
 513 }
 514
 515 int obd_init_caches(void)
 516 {
 517         ENTRY;
 518
 519         LASSERT(obd_device_cachep == NULL);
 520         obd_device_cachep = cfs_mem_cache_create("ll_obd_dev_cache",
 521                                               sizeof(struct obd_device), 0, 0);
 522         if (!obd_device_cachep)
 523                 GOTO(out, -ENOMEM);
 524
 525         LASSERT(obdo_cachep == NULL);
 526         obdo_cachep = cfs_mem_cache_create("ll_obdo_cache", sizeof(struct obdo),
 527                                         0, 0);
 528         if (!obdo_cachep)
 529                 GOTO(out, -ENOMEM);
 530
 531         LASSERT(import_cachep == NULL);
 532         import_cachep = cfs_mem_cache_create("ll_import_cache",
 533                                           sizeof(struct obd_import),
 534                                           0, 0);
 535         if (!import_cachep)
 536                 GOTO(out, -ENOMEM);
 537
 538         RETURN(0);
 539  out:
 540         obd_cleanup_caches();
 541         RETURN(-ENOMEM);
 542
 543 }
 544
 545 /* map connection to client */
 546 struct obd_export *class_conn2export(struct lustre_handle *conn)
 547 {
 548         struct obd_export *export;
 549         ENTRY;
 550
 551         if (!conn) {
 552                 CDEBUG(D_CACHE, "looking for null handle\n");
 553                 RETURN(NULL);
 554         }
 555
 556         if (conn->cookie == -1) {  /* this means assign a new connection */
 557                 CDEBUG(D_CACHE, "want a new connection\n");
 558                 RETURN(NULL);
 559         }
 560
 561         CDEBUG(D_INFO, "looking for export cookie "LPX64"\n", conn->cookie);
 562         export = class_handle2object(conn->cookie);
 563         RETURN(export);
 564 }
 565
 566 struct obd_device *class_exp2obd(struct obd_export *exp)
 567 {
 568         if (exp)
 569                 return exp->exp_obd;
 570         return NULL;
 571 }
 572
 573 struct obd_device *class_conn2obd(struct lustre_handle *conn)
 574 {
 575         struct obd_export *export;
 576         export = class_conn2export(conn);
 577         if (export) {
 578                 struct obd_device *obd = export->exp_obd;
 579                 class_export_put(export);
 580                 return obd;
 581         }
 582         return NULL;
 583 }
 584
 585 struct obd_import *class_exp2cliimp(struct obd_export *exp)
 586 {
 587         struct obd_device *obd = exp->exp_obd;
 588         if (obd == NULL)
 589                 return NULL;
 590         return obd->u.cli.cl_import;
 591 }
 592
 593 struct obd_import *class_conn2cliimp(struct lustre_handle *conn)
 594 {
 595         struct obd_device *obd = class_conn2obd(conn);
 596         if (obd == NULL)
 597                 return NULL;
 598         return obd->u.cli.cl_import;
 599 }
 600
 601 /* Export management functions */
 602 static void export_handle_addref(void *export)
 603 {
 604         class_export_get(export);
 605 }
 606
 607 void __class_export_put(struct obd_export *exp)
 608 {
 609         if (atomic_dec_and_test(&exp->exp_refcount)) {
 610                 LASSERT (list_empty(&exp->exp_obd_chain));
 611
 612                 CDEBUG(D_IOCTL, "final put %p/%s\n",
 613                        exp, exp->exp_client_uuid.uuid);
 614
 615                 spin_lock(&obd_zombie_impexp_lock);
 616                 list_add(&exp->exp_obd_chain, &obd_zombie_exports);
 617                 spin_unlock(&obd_zombie_impexp_lock);
 618
 619                 if (obd_zombie_impexp_notify != NULL)
 620                         obd_zombie_impexp_notify();
 621         }
 622 }
 623 EXPORT_SYMBOL(__class_export_put);
 624
 625 void class_export_destroy(struct obd_export *exp)
 626 {
 627         struct obd_device *obd = exp->exp_obd;
 628
 629         LASSERT (atomic_read(&exp->exp_refcount) == 0);
 630
 631         CDEBUG(D_IOCTL, "destroying export %p/%s\n", exp,
 632                exp->exp_client_uuid.uuid);
 633
 634         LASSERT(obd != NULL);
 635
 636         /* "Local" exports (lctl, LOV->{mdc,osc}) have no connection. */
 637         if (exp->exp_connection)
 638                 ptlrpc_put_connection_superhack(exp->exp_connection);
 639
 640         LASSERT(list_empty(&exp->exp_outstanding_replies));
 641         LASSERT(list_empty(&exp->exp_handle.h_link));
 642         obd_destroy_export(exp);
 643
 644         OBD_FREE(exp, sizeof(*exp));
 645         class_decref(obd);
 646 }
 647
 648 /* Creates a new export, adds it to the hash table, and returns a
 649  * pointer to it. The refcount is 2: one for the hash reference, and
 650  * one for the pointer returned by this function. */
 651 struct obd_export *class_new_export(struct obd_device *obd,
 652                                     struct obd_uuid *cluuid)
 653 {
 654         struct obd_export *export, *tmp;
 655
 656         OBD_ALLOC(export, sizeof(*export));
 657         if (!export)
 658                 return ERR_PTR(-ENOMEM);
 659
 660         export->exp_conn_cnt = 0;
 661         atomic_set(&export->exp_refcount, 2);
 662         atomic_set(&export->exp_rpc_count, 0);
 663         export->exp_obd = obd;
 664         CFS_INIT_LIST_HEAD(&export->exp_outstanding_replies);
 665         /* XXX this should be in LDLM init */
 666         CFS_INIT_LIST_HEAD(&export->exp_ldlm_data.led_held_locks);
 667         spin_lock_init(&export->exp_ldlm_data.led_lock);
 668
 669         CFS_INIT_LIST_HEAD(&export->exp_handle.h_link);
 670         class_handle_hash(&export->exp_handle, export_handle_addref);
 671         export->exp_last_request_time = CURRENT_SECONDS;
 672         spin_lock_init(&export->exp_lock);
 673
 674         export->exp_client_uuid = *cluuid;
 675         obd_init_export(export);
 676
 677         spin_lock(&obd->obd_dev_lock);
 678         if (!obd_uuid_equals(cluuid, &obd->obd_uuid)) {
 679                 list_for_each_entry(tmp, &obd->obd_exports, exp_obd_chain) {
 680                         if (obd_uuid_equals(cluuid, &tmp->exp_client_uuid)) {
 681                                 spin_unlock(&obd->obd_dev_lock);
 682                                 CWARN("%s: denying duplicate export for %s\n",
 683                                       obd->obd_name, cluuid->uuid);
 684                                 class_handle_unhash(&export->exp_handle);
 685                                 OBD_FREE_PTR(export);
 686                                 return ERR_PTR(-EALREADY);
 687                         }
 688                 }
 689         }
 690         LASSERT(!obd->obd_stopping); /* shouldn't happen, but might race */
 691         class_incref(obd);
 692         list_add(&export->exp_obd_chain, &export->exp_obd->obd_exports);
 693         list_add_tail(&export->exp_obd_chain_timed,
 694                       &export->exp_obd->obd_exports_timed);
 695         export->exp_obd->obd_num_exports++;
 696         spin_unlock(&obd->obd_dev_lock);
 697
 698         return export;
 699 }
 700 EXPORT_SYMBOL(class_new_export);
 701
 702 void class_unlink_export(struct obd_export *exp)
 703 {
 704         class_handle_unhash(&exp->exp_handle);
 705
 706         spin_lock(&exp->exp_obd->obd_dev_lock);
 707         list_del_init(&exp->exp_obd_chain);
 708         list_del_init(&exp->exp_obd_chain_timed);
 709         exp->exp_obd->obd_num_exports--;
 710         spin_unlock(&exp->exp_obd->obd_dev_lock);
 711
 712         class_export_put(exp);
 713 }
 714 EXPORT_SYMBOL(class_unlink_export);
 715
 716 /* Import management functions */
 717 static void import_handle_addref(void *import)
 718 {
 719         class_import_get(import);
 720 }
 721
 722 struct obd_import *class_import_get(struct obd_import *import)
 723 {
 724         LASSERT(atomic_read(&import->imp_refcount) >= 0);
 725         LASSERT(atomic_read(&import->imp_refcount) < 0x5a5a5a);
 726         atomic_inc(&import->imp_refcount);
 727         CDEBUG(D_INFO, "import %p refcount=%d\n", import,
 728                atomic_read(&import->imp_refcount));
 729         return import;
 730 }
 731 EXPORT_SYMBOL(class_import_get);
 732
 733 void class_import_put(struct obd_import *import)
 734 {
 735         ENTRY;
 736
 737         CDEBUG(D_INFO, "import %p refcount=%d\n", import,
 738                atomic_read(&import->imp_refcount) - 1);
 739
 740         LASSERT(atomic_read(&import->imp_refcount) > 0);
 741         LASSERT(atomic_read(&import->imp_refcount) < 0x5a5a5a);
 742         LASSERT(list_empty(&import->imp_zombie_chain));
 743
 744         if (atomic_dec_and_test(&import->imp_refcount)) {
 745
 746                 CDEBUG(D_INFO, "final put import %p\n", import);
 747
 748                 spin_lock(&obd_zombie_impexp_lock);
 749                 list_add(&import->imp_zombie_chain, &obd_zombie_imports);
 750                 spin_unlock(&obd_zombie_impexp_lock);
 751
 752                 if (obd_zombie_impexp_notify != NULL)
 753                         obd_zombie_impexp_notify();
 754         }
 755
 756         EXIT;
 757 }
 758
 759 void class_import_destroy(struct obd_import *import)
 760 {
 761         ENTRY;
 762
 763         CDEBUG(D_IOCTL, "destroying import %p\n", import);
 764
 765         LASSERT(atomic_read(&import->imp_refcount) == 0);
 766
 767         ptlrpc_put_connection_superhack(import->imp_connection);
 768
 769         while (!list_empty(&import->imp_conn_list)) {
 770                 struct obd_import_conn *imp_conn;
 771
 772                 imp_conn = list_entry(import->imp_conn_list.next,
 773                                       struct obd_import_conn, oic_item);
 774                 list_del(&imp_conn->oic_item);
 775                 ptlrpc_put_connection_superhack(imp_conn->oic_conn);
 776                 OBD_FREE(imp_conn, sizeof(*imp_conn));
 777         }
 778
 779         LASSERT(list_empty(&import->imp_handle.h_link));
 780         class_decref(import->imp_obd);
 781         OBD_FREE(import, sizeof(*import));
 782
 783         EXIT;
 784 }
 785 EXPORT_SYMBOL(class_import_put);
 786
 787 struct obd_import *class_new_import(struct obd_device *obd)
 788 {
 789         struct obd_import *imp;
 790
 791         OBD_ALLOC(imp, sizeof(*imp));
 792         if (imp == NULL)
 793                 return NULL;
 794
 795         CFS_INIT_LIST_HEAD(&imp->imp_zombie_chain);
 796         CFS_INIT_LIST_HEAD(&imp->imp_replay_list);
 797         CFS_INIT_LIST_HEAD(&imp->imp_sending_list);
 798         CFS_INIT_LIST_HEAD(&imp->imp_delayed_list);
 799         spin_lock_init(&imp->imp_lock);
 800         imp->imp_last_success_conn = 0;
 801         imp->imp_state = LUSTRE_IMP_NEW;
 802         imp->imp_obd = class_incref(obd);
 803         cfs_waitq_init(&imp->imp_recovery_waitq);
 804
 805         atomic_set(&imp->imp_refcount, 2);
 806         atomic_set(&imp->imp_inflight, 0);
 807         atomic_set(&imp->imp_replay_inflight, 0);
 808         CFS_INIT_LIST_HEAD(&imp->imp_conn_list);
 809         CFS_INIT_LIST_HEAD(&imp->imp_handle.h_link);
 810         class_handle_hash(&imp->imp_handle, import_handle_addref);
 811
 812         /* the default magic is V1, will be used in connect RPC, and
 813          * then adjusted according to the flags in request/reply. */
 814         imp->imp_msg_magic = LUSTRE_MSG_MAGIC_V1;
 815
 816         return imp;
 817 }
 818 EXPORT_SYMBOL(class_new_import);
 819
 820 void class_destroy_import(struct obd_import *import)
 821 {
 822         LASSERT(import != NULL);
 823         LASSERT(import != LP_POISON);
 824
 825         class_handle_unhash(&import->imp_handle);
 826
 827         import->imp_generation++;
 828         class_import_put(import);
 829 }
 830 EXPORT_SYMBOL(class_destroy_import);
 831
 832 /* A connection defines an export context in which preallocation can
 833    be managed. This releases the export pointer reference, and returns
 834    the export handle, so the export refcount is 1 when this function
 835    returns. */
 836 int class_connect(struct lustre_handle *conn, struct obd_device *obd,
 837                   struct obd_uuid *cluuid)
 838 {
 839         struct obd_export *export;
 840         LASSERT(conn != NULL);
 841         LASSERT(obd != NULL);
 842         LASSERT(cluuid != NULL);
 843         ENTRY;
 844
 845         export = class_new_export(obd, cluuid);
 846         if (IS_ERR(export))
 847                 RETURN(PTR_ERR(export));
 848
 849         conn->cookie = export->exp_handle.h_cookie;
 850         class_export_put(export);
 851
 852         CDEBUG(D_IOCTL, "connect: client %s, cookie "LPX64"\n",
 853                cluuid->uuid, conn->cookie);
 854         RETURN(0);
 855 }
 856 EXPORT_SYMBOL(class_connect);
 857
 858 /* This function removes two references from the export: one for the
 859  * hash entry and one for the export pointer passed in.  The export
 860  * pointer passed to this function is destroyed should not be used
 861  * again. */
 862 int class_disconnect(struct obd_export *export)
 863 {
 864         int already_disconnected;
 865         ENTRY;
 866
 867         if (export == NULL) {
 868                 fixme();
 869                 CDEBUG(D_IOCTL, "attempting to free NULL export %p\n", export);
 870                 RETURN(-EINVAL);
 871         }
 872
 873         spin_lock(&export->exp_lock);
 874         already_disconnected = export->exp_disconnected;
 875         export->exp_disconnected = 1;
 876         spin_unlock(&export->exp_lock);
 877
 878         /* class_cleanup(), abort_recovery(), and class_fail_export()
 879          * all end up in here, and if any of them race we shouldn't
 880          * call extra class_export_puts(). */
 881         if (already_disconnected)
 882                 RETURN(0);
 883
 884         CDEBUG(D_IOCTL, "disconnect: cookie "LPX64"\n",
 885                export->exp_handle.h_cookie);
 886
 887         class_unlink_export(export);
 888         class_export_put(export);
 889         RETURN(0);
 890 }
 891
 892 static void class_disconnect_export_list(struct list_head *list, int flags)
 893 {
 894         int rc;
 895         struct lustre_handle fake_conn;
 896         struct obd_export *fake_exp, *exp;
 897         ENTRY;
 898
 899         /* It's possible that an export may disconnect itself, but
 900          * nothing else will be added to this list. */
 901         while (!list_empty(list)) {
 902                 exp = list_entry(list->next, struct obd_export, exp_obd_chain);
 903                 class_export_get(exp);
 904                 exp->exp_flags = flags;
 905
 906                 if (obd_uuid_equals(&exp->exp_client_uuid,
 907                                     &exp->exp_obd->obd_uuid)) {
 908                         CDEBUG(D_HA,
 909                                "exp %p export uuid == obd uuid, don't discon\n",
 910                                exp);
 911                         /* Need to delete this now so we don't end up pointing
 912                          * to work_list later when this export is cleaned up. */
 913                         list_del_init(&exp->exp_obd_chain);
 914                         class_export_put(exp);
 915                         continue;
 916                 }
 917
 918                 fake_conn.cookie = exp->exp_handle.h_cookie;
 919                 fake_exp = class_conn2export(&fake_conn);
 920                 if (!fake_exp) {
 921                         class_export_put(exp);
 922                         continue;
 923                 }
 924                 fake_exp->exp_flags = flags;
 925                 rc = obd_disconnect(fake_exp);
 926                 class_export_put(exp);
 927                 if (rc) {
 928                         CDEBUG(D_HA, "disconnecting export %p failed: %d\n",
 929                                exp, rc);
 930                 } else {
 931                         CDEBUG(D_HA, "export %p disconnected\n", exp);
 932                 }
 933         }
 934         EXIT;
 935 }
 936
 937 static inline int get_exp_flags_from_obd(struct obd_device *obd)
 938 {
 939         return ((obd->obd_fail ? OBD_OPT_FAILOVER : 0) |
 940                 (obd->obd_force ? OBD_OPT_FORCE : 0));
 941 }
 942
 943 void class_disconnect_exports(struct obd_device *obd)
 944 {
 945         struct list_head work_list;
 946         ENTRY;
 947
 948         /* Move all of the exports from obd_exports to a work list, en masse. */
 949         spin_lock(&obd->obd_dev_lock);
 950         list_add(&work_list, &obd->obd_exports);
 951         list_del_init(&obd->obd_exports);
 952         spin_unlock(&obd->obd_dev_lock);
 953
 954         CDEBUG(D_HA, "OBD device %d (%p) has exports, "
 955                "disconnecting them\n", obd->obd_minor, obd);
 956         class_disconnect_export_list(&work_list, get_exp_flags_from_obd(obd));
 957         EXIT;
 958 }
 959 EXPORT_SYMBOL(class_disconnect_exports);
 960
 961 /* Remove exports that have not completed recovery.
 962  */
 963 void class_disconnect_stale_exports(struct obd_device *obd)
 964 {
 965         struct list_head work_list;
 966         struct list_head *pos, *n;
 967         struct obd_export *exp;
 968         int cnt = 0;
 969         ENTRY;
 970
 971         CFS_INIT_LIST_HEAD(&work_list);
 972         spin_lock(&obd->obd_dev_lock);
 973         list_for_each_safe(pos, n, &obd->obd_exports) {
 974                 exp = list_entry(pos, struct obd_export, exp_obd_chain);
 975                 if (exp->exp_replay_needed) {
 976                         list_del(&exp->exp_obd_chain);
 977                         list_add(&exp->exp_obd_chain, &work_list);
 978                         cnt++;
 979                 }
 980         }
 981         spin_unlock(&obd->obd_dev_lock);
 982
 983         CDEBUG(D_ERROR, "%s: disconnecting %d stale clients\n",
 984                obd->obd_name, cnt);
 985         class_disconnect_export_list(&work_list, get_exp_flags_from_obd(obd));
 986         EXIT;
 987 }
 988 EXPORT_SYMBOL(class_disconnect_stale_exports);
 989
 990 int oig_init(struct obd_io_group **oig_out)
 991 {
 992         struct obd_io_group *oig;
 993         ENTRY;
 994
 995         OBD_ALLOC(oig, sizeof(*oig));
 996         if (oig == NULL)
 997                 RETURN(-ENOMEM);
 998
 999         spin_lock_init(&oig->oig_lock);
1000         oig->oig_rc = 0;
1001         oig->oig_pending = 0;
1002         atomic_set(&oig->oig_refcount, 1);
1003         cfs_waitq_init(&oig->oig_waitq);
1004         CFS_INIT_LIST_HEAD(&oig->oig_occ_list);
1005
1006         *oig_out = oig;
1007         RETURN(0);
1008 };
1009 EXPORT_SYMBOL(oig_init);
1010
1011 static inline void oig_grab(struct obd_io_group *oig)
1012 {
1013         atomic_inc(&oig->oig_refcount);
1014 }
1015
1016 void oig_release(struct obd_io_group *oig)
1017 {
1018         if (atomic_dec_and_test(&oig->oig_refcount))
1019                 OBD_FREE(oig, sizeof(*oig));
1020 }
1021 EXPORT_SYMBOL(oig_release);
1022
1023 int oig_add_one(struct obd_io_group *oig, struct oig_callback_context *occ)
1024 {
1025         int rc = 0;
1026         CDEBUG(D_CACHE, "oig %p ready to roll\n", oig);
1027         spin_lock(&oig->oig_lock);
1028         if (oig->oig_rc) {
1029                 rc = oig->oig_rc;
1030         } else {
1031                 oig->oig_pending++;
1032                 if (occ != NULL)
1033                         list_add_tail(&occ->occ_oig_item, &oig->oig_occ_list);
1034         }
1035         spin_unlock(&oig->oig_lock);
1036         oig_grab(oig);
1037
1038         return rc;
1039 }
1040 EXPORT_SYMBOL(oig_add_one);
1041
1042 void oig_complete_one(struct obd_io_group *oig,
1043                       struct oig_callback_context *occ, int rc)
1044 {
1045         cfs_waitq_t *wake = NULL;
1046         int old_rc;
1047
1048         spin_lock(&oig->oig_lock);
1049
1050         if (occ != NULL)
1051                 list_del_init(&occ->occ_oig_item);
1052
1053         old_rc = oig->oig_rc;
1054         if (oig->oig_rc == 0 && rc != 0)
1055                 oig->oig_rc = rc;
1056
1057         if (--oig->oig_pending <= 0)
1058                 wake = &oig->oig_waitq;
1059
1060         spin_unlock(&oig->oig_lock);
1061
1062         CDEBUG(D_CACHE, "oig %p completed, rc %d -> %d via %d, %d now "
1063                         "pending (racey)\n", oig, old_rc, oig->oig_rc, rc,
1064                         oig->oig_pending);
1065         if (wake)
1066                 cfs_waitq_signal(wake);
1067         oig_release(oig);
1068 }
1069 EXPORT_SYMBOL(oig_complete_one);
1070
1071 static int oig_done(struct obd_io_group *oig)
1072 {
1073         int rc = 0;
1074         spin_lock(&oig->oig_lock);
1075         if (oig->oig_pending <= 0)
1076                 rc = 1;
1077         spin_unlock(&oig->oig_lock);
1078         return rc;
1079 }
1080
1081 static void interrupted_oig(void *data)
1082 {
1083         struct obd_io_group *oig = data;
1084         struct oig_callback_context *occ;
1085
1086         spin_lock(&oig->oig_lock);
1087         /* We need to restart the processing each time we drop the lock, as
1088          * it is possible other threads called oig_complete_one() to remove
1089          * an entry elsewhere in the list while we dropped lock.  We need to
1090          * drop the lock because osc_ap_completion() calls oig_complete_one()
1091          * which re-gets this lock ;-) as well as a lock ordering issue. */
1092 restart:
1093         list_for_each_entry(occ, &oig->oig_occ_list, occ_oig_item) {
1094                 if (occ->interrupted)
1095                         continue;
1096                 occ->interrupted = 1;
1097                 spin_unlock(&oig->oig_lock);
1098                 occ->occ_interrupted(occ);
1099                 spin_lock(&oig->oig_lock);
1100                 goto restart;
1101         }
1102         spin_unlock(&oig->oig_lock);
1103 }
1104
1105 int oig_wait(struct obd_io_group *oig)
1106 {
1107         struct l_wait_info lwi = LWI_INTR(interrupted_oig, oig);
1108         int rc;
1109
1110         CDEBUG(D_CACHE, "waiting for oig %p\n", oig);
1111
1112         do {
1113                 rc = l_wait_event(oig->oig_waitq, oig_done(oig), &lwi);
1114                 LASSERTF(rc == 0 || rc == -EINTR, "rc: %d\n", rc);
1115                 /* we can't continue until the oig has emptied and stopped
1116                  * referencing state that the caller will free upon return */
1117                 if (rc == -EINTR)
1118                         lwi = (struct l_wait_info){ 0, };
1119         } while (rc == -EINTR);
1120
1121         LASSERTF(oig->oig_pending == 0,
1122                  "exiting oig_wait(oig = %p) with %d pending\n", oig,
1123                  oig->oig_pending);
1124
1125         CDEBUG(D_CACHE, "done waiting on oig %p rc %d\n", oig, oig->oig_rc);
1126         return oig->oig_rc;
1127 }
1128 EXPORT_SYMBOL(oig_wait);
1129
1130 void class_fail_export(struct obd_export *exp)
1131 {
1132         int rc, already_failed;
1133
1134         spin_lock(&exp->exp_lock);
1135         already_failed = exp->exp_failed;
1136         exp->exp_failed = 1;
1137         spin_unlock(&exp->exp_lock);
1138
1139         if (already_failed) {
1140                 CDEBUG(D_HA, "disconnecting dead export %p/%s; skipping\n",
1141                        exp, exp->exp_client_uuid.uuid);
1142                 return;
1143         }
1144
1145         CDEBUG(D_HA, "disconnecting export %p/%s\n",
1146                exp, exp->exp_client_uuid.uuid);
1147
1148         if (obd_dump_on_timeout)
1149                 libcfs_debug_dumplog();
1150
1151         /* Most callers into obd_disconnect are removing their own reference
1152          * (request, for example) in addition to the one from the hash table.
1153          * We don't have such a reference here, so make one. */
1154         class_export_get(exp);
1155         rc = obd_disconnect(exp);
1156         if (rc)
1157                 CERROR("disconnecting export %p failed: %d\n", exp, rc);
1158         else
1159                 CDEBUG(D_HA, "disconnected export %p/%s\n",
1160                        exp, exp->exp_client_uuid.uuid);
1161 }
1162 EXPORT_SYMBOL(class_fail_export);
1163
1164 char *obd_export_nid2str(struct obd_export *exp)
1165 {
1166         if (exp->exp_connection != NULL)
1167                 return libcfs_nid2str(exp->exp_connection->c_peer.nid);
1168
1169         return "(no nid)";
1170 }
1171 EXPORT_SYMBOL(obd_export_nid2str);
1172
1173 #define EVICT_BATCH 32
1174 int obd_export_evict_by_nid(struct obd_device *obd, char *nid)
1175 {
1176         struct obd_export *doomed_exp[EVICT_BATCH] = { NULL };
1177         struct list_head *p;
1178         int exports_evicted = 0, num_to_evict = 0, i;
1179
1180 search_again:
1181         spin_lock(&obd->obd_dev_lock);
1182         list_for_each(p, &obd->obd_exports) {
1183                 doomed_exp[num_to_evict] = list_entry(p, struct obd_export,
1184                                                       exp_obd_chain);
1185                 if (strcmp(obd_export_nid2str(doomed_exp[num_to_evict]),
1186                            nid) == 0) {
1187                         class_export_get(doomed_exp[num_to_evict]);
1188                         if (++num_to_evict == EVICT_BATCH)
1189                                 break;
1190                 }
1191         }
1192         spin_unlock(&obd->obd_dev_lock);
1193
1194         for (i = 0; i < num_to_evict; i++) {
1195                 exports_evicted++;
1196                 CWARN("%s: evict NID '%s' (%s) #%d at adminstrative request\n",
1197                        obd->obd_name, nid, doomed_exp[i]->exp_client_uuid.uuid,
1198                        exports_evicted);
1199                 class_fail_export(doomed_exp[i]);
1200                 class_export_put(doomed_exp[i]);
1201         }
1202         if (num_to_evict == EVICT_BATCH) {
1203                 num_to_evict = 0;
1204                 goto search_again;
1205         }
1206
1207         if (!exports_evicted)
1208                 CDEBUG(D_HA,"%s: can't disconnect NID '%s': no exports found\n",
1209                        obd->obd_name, nid);
1210         return exports_evicted;
1211 }
1212 EXPORT_SYMBOL(obd_export_evict_by_nid);
1213
1214 int obd_export_evict_by_uuid(struct obd_device *obd, char *uuid)
1215 {
1216         struct obd_export *doomed_exp = NULL;
1217         struct list_head *p;
1218         struct obd_uuid doomed;
1219         int exports_evicted = 0;
1220
1221         obd_str2uuid(&doomed, uuid);
1222
1223         spin_lock(&obd->obd_dev_lock);
1224         list_for_each(p, &obd->obd_exports) {
1225                 doomed_exp = list_entry(p, struct obd_export, exp_obd_chain);
1226
1227                 if (obd_uuid_equals(&doomed, &doomed_exp->exp_client_uuid)) {
1228                         class_export_get(doomed_exp);
1229                         break;
1230                 }
1231                 doomed_exp = NULL;
1232         }
1233         spin_unlock(&obd->obd_dev_lock);
1234
1235         if (doomed_exp == NULL) {
1236                 CERROR("%s: can't disconnect %s: no exports found\n",
1237                        obd->obd_name, uuid);
1238         } else {
1239                 CWARN("%s: evicting %s at adminstrative request\n",
1240                        obd->obd_name, doomed_exp->exp_client_uuid.uuid);
1241                 class_fail_export(doomed_exp);
1242                 class_export_put(doomed_exp);
1243                 exports_evicted++;
1244         }
1245
1246         return exports_evicted;
1247 }
1248 EXPORT_SYMBOL(obd_export_evict_by_uuid);
1249
1250 void obd_zombie_impexp_cull(void)
1251 {
1252         struct obd_import *import;
1253         struct obd_export *export;
1254
1255         do {
1256                 spin_lock (&obd_zombie_impexp_lock);
1257
1258                 import = NULL;
1259                 if (!list_empty(&obd_zombie_imports)) {
1260                         import = list_entry(obd_zombie_imports.next,
1261                                             struct obd_import,
1262                                             imp_zombie_chain);
1263                         list_del(&import->imp_zombie_chain);
1264                 }
1265
1266                 export = NULL;
1267                 if (!list_empty(&obd_zombie_exports)) {
1268                         export = list_entry(obd_zombie_exports.next,
1269                                             struct obd_export,
1270                                             exp_obd_chain);
1271                         list_del_init(&export->exp_obd_chain);
1272                 }
1273
1274                 spin_unlock(&obd_zombie_impexp_lock);
1275
1276                 if (import != NULL)
1277                         class_import_destroy(import);
1278
1279                 if (export != NULL)
1280                         class_export_destroy(export);
1281
1282         } while (import != NULL || export != NULL);
1283 }
1284 EXPORT_SYMBOL(obd_zombie_impexp_cull);
1285
1286 void obd_zombie_impexp_init(void)
1287 {
1288         INIT_LIST_HEAD(&obd_zombie_imports);
1289         INIT_LIST_HEAD(&obd_zombie_exports);
1290         spin_lock_init(&obd_zombie_impexp_lock);
1291 }