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 Lustre, http://www.lustre.org.
   7  *
   8  *   Lustre is free software; you can redistribute it and/or
   9  *   modify it under the terms of version 2 of the GNU General Public
  10  *   License as published by the Free Software Foundation.
  11  *
  12  *   Lustre is distributed in the hope that it will be useful,
  13  *   but WITHOUT ANY WARRANTY; without even the implied warranty of
  14  *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15  *   GNU General Public License for more details.
  16  *
  17  *   You should have received a copy of the GNU General Public License
  18  *   along with Lustre; if not, write to the Free Software
  19  *   Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
  20  *
  21  * These are the only exported functions, they provide some generic
  22  * infrastructure for managing object devices
  23  */
  24
  25 #define DEBUG_SUBSYSTEM S_CLASS
  26 #ifdef __KERNEL__
  27 #include <linux/kmod.h>   /* for request_module() */
  28 #include <linux/module.h>
  29 #include <linux/obd_class.h>
  30 #include <linux/random.h>
  31 #include <linux/slab.h>
  32 #include <linux/pagemap.h>
  33 #else
  34 #include <liblustre.h>
  35 #include <linux/obd_class.h>
  36 #include <linux/obd.h>
  37 #endif
  38 #include <linux/lprocfs_status.h>
  39 #include <linux/lustre_sec.h>
  40
  41 extern struct list_head obd_types;
  42 static spinlock_t obd_types_lock = SPIN_LOCK_UNLOCKED;
  43 kmem_cache_t *obdo_cachep = NULL;
  44 kmem_cache_t *import_cachep = NULL;
  45
  46 extern kmem_cache_t *capa_cachep;
  47
  48 int (*ptlrpc_put_connection_superhack)(struct ptlrpc_connection *c);
  49 void (*ptlrpc_abort_inflight_superhack)(struct obd_import *imp);
  50
  51 /*
  52  * support functions: we could use inter-module communication, but this
  53  * is more portable to other OS's
  54  */
  55 static struct obd_type *class_search_type(char *name)
  56 {
  57         struct list_head *tmp;
  58         struct obd_type *type;
  59
  60         spin_lock(&obd_types_lock);
  61         list_for_each(tmp, &obd_types) {
  62                 type = list_entry(tmp, struct obd_type, typ_chain);
  63                 if (strlen(type->typ_name) == strlen(name) &&
  64                     strcmp(type->typ_name, name) == 0) {
  65                         spin_unlock(&obd_types_lock);
  66                         return type;
  67                 }
  68         }
  69         spin_unlock(&obd_types_lock);
  70         return NULL;
  71 }
  72
  73 struct obd_type *class_get_type(char *name)
  74 {
  75         struct obd_type *type = class_search_type(name);
  76
  77 #ifdef CONFIG_KMOD
  78         if (!type) {
  79                 if (!request_module(name)) {
  80                         CDEBUG(D_INFO, "Loaded module '%s'\n", name);
  81                         type = class_search_type(name);
  82                 } else
  83                         CDEBUG(D_INFO, "Can't load module '%s'\n", name);
  84         }
  85 #endif
  86         if (type)
  87                 try_module_get(type->typ_ops->o_owner);
  88         return type;
  89 }
  90
  91 void class_put_type(struct obd_type *type)
  92 {
  93         LASSERT(type);
  94         module_put(type->typ_ops->o_owner);
  95 }
  96
  97 int class_register_type(struct obd_ops *ops, struct md_ops *md_ops,
  98                         struct lprocfs_vars *vars, char *name)
  99 {
 100         struct obd_type *type;
 101         int rc = 0;
 102         ENTRY;
 103
 104         LASSERT(strnlen(name, 1024) < 1024);    /* sanity check */
 105
 106         if (class_search_type(name)) {
 107                 CDEBUG(D_IOCTL, "Type %s already registered\n", name);
 108                 RETURN(-EEXIST);
 109         }
 110
 111         rc = -ENOMEM;
 112         OBD_ALLOC(type, sizeof(*type));
 113         if (type == NULL)
 114                 RETURN(rc);
 115
 116         OBD_ALLOC(type->typ_ops, sizeof(*type->typ_ops));
 117         OBD_ALLOC(type->typ_name, strlen(name) + 1);
 118         if (md_ops)
 119                 OBD_ALLOC(type->typ_md_ops, sizeof(*type->typ_md_ops));
 120         if (type->typ_ops == NULL || type->typ_name == NULL ||
 121                         (md_ops && type->typ_md_ops == NULL))
 122                 GOTO (failed, rc);
 123
 124         *(type->typ_ops) = *ops;
 125         if (md_ops)
 126                 *(type->typ_md_ops) = *md_ops;
 127         else
 128                 type->typ_md_ops = NULL;
 129         strcpy(type->typ_name, name);
 130
 131 #ifdef LPROCFS
 132         type->typ_procroot = lprocfs_register(type->typ_name, proc_lustre_root,
 133                                               vars, type);
 134 #endif
 135         if (IS_ERR(type->typ_procroot)) {
 136                 rc = PTR_ERR(type->typ_procroot);
 137                 type->typ_procroot = NULL;
 138                 GOTO (failed, rc);
 139         }
 140
 141         spin_lock(&obd_types_lock);
 142         list_add(&type->typ_chain, &obd_types);
 143         spin_unlock(&obd_types_lock);
 144
 145         RETURN (0);
 146
 147  failed:
 148         if (type->typ_name != NULL)
 149                 OBD_FREE(type->typ_name, strlen(name) + 1);
 150         if (type->typ_ops != NULL)
 151                 OBD_FREE (type->typ_ops, sizeof (*type->typ_ops));
 152         if (type->typ_md_ops != NULL)
 153                 OBD_FREE (type->typ_md_ops, sizeof (*type->typ_md_ops));
 154         OBD_FREE(type, sizeof(*type));
 155         RETURN(rc);
 156 }
 157
 158 int class_unregister_type(char *name)
 159 {
 160         struct obd_type *type = class_search_type(name);
 161         ENTRY;
 162
 163         if (!type) {
 164                 CERROR("unknown obd type\n");
 165                 RETURN(-EINVAL);
 166         }
 167
 168         if (type->typ_refcnt) {
 169                 CERROR("type %s has refcount (%d)\n", name, type->typ_refcnt);
 170                 /* This is a bad situation, let's make the best of it */
 171                 /* Remove ops, but leave the name for debugging */
 172                 OBD_FREE(type->typ_ops, sizeof(*type->typ_ops));
 173                 RETURN(-EBUSY);
 174         }
 175
 176         if (type->typ_procroot) {
 177                 lprocfs_remove(type->typ_procroot);
 178                 type->typ_procroot = NULL;
 179         }
 180
 181         spin_lock(&obd_types_lock);
 182         list_del(&type->typ_chain);
 183         spin_unlock(&obd_types_lock);
 184         OBD_FREE(type->typ_name, strlen(name) + 1);
 185         if (type->typ_ops != NULL)
 186                 OBD_FREE(type->typ_ops, sizeof(*type->typ_ops));
 187         if (type->typ_md_ops != NULL)
 188                 OBD_FREE (type->typ_md_ops, sizeof(*type->typ_md_ops));
 189         OBD_FREE(type, sizeof(*type));
 190         RETURN(0);
 191 } /* class_unregister_type */
 192
 193 struct obd_device *class_newdev(struct obd_type *type)
 194 {
 195         struct obd_device *result = NULL;
 196         int i;
 197
 198         spin_lock(&obd_dev_lock);
 199         for (i = 0 ; i < MAX_OBD_DEVICES && result == NULL; i++) {
 200                 struct obd_device *obd = &obd_dev[i];
 201                 if (!obd->obd_type) {
 202                         LASSERT(obd->obd_minor == i);
 203                         memset(obd, 0, sizeof(*obd));
 204                         obd->obd_minor = i;
 205                         obd->obd_type = type;
 206                         result = obd;
 207                 }
 208         }
 209         spin_unlock(&obd_dev_lock);
 210         return result;
 211 }
 212
 213 void class_release_dev(struct obd_device *obd)
 214 {
 215         int minor = obd->obd_minor;
 216
 217         spin_lock(&obd_dev_lock);
 218         obd->obd_type = NULL;
 219         //memset(obd, 0, sizeof(*obd));
 220         obd->obd_minor = minor;
 221         spin_unlock(&obd_dev_lock);
 222 }
 223
 224 int class_name2dev(char *name)
 225 {
 226         int i;
 227
 228         if (!name)
 229                 return -1;
 230
 231         spin_lock(&obd_dev_lock);
 232         for (i = 0; i < MAX_OBD_DEVICES; i++) {
 233                 struct obd_device *obd = &obd_dev[i];
 234                 if (obd->obd_name && strcmp(name, obd->obd_name) == 0) {
 235                         spin_unlock(&obd_dev_lock);
 236                         return i;
 237                 }
 238         }
 239         spin_unlock(&obd_dev_lock);
 240         return -1;
 241 }
 242
 243 struct obd_device *class_name2obd(char *name)
 244 {
 245         int dev = class_name2dev(name);
 246         if (dev < 0)
 247                 return NULL;
 248         return &obd_dev[dev];
 249 }
 250
 251 int class_uuid2dev(struct obd_uuid *uuid)
 252 {
 253         int i;
 254         spin_lock(&obd_dev_lock);
 255         for (i = 0; i < MAX_OBD_DEVICES; i++) {
 256                 struct obd_device *obd = &obd_dev[i];
 257                 if (obd_uuid_equals(uuid, &obd->obd_uuid)) {
 258                         spin_unlock(&obd_dev_lock);
 259                         return i;
 260                 }
 261         }
 262         spin_unlock(&obd_dev_lock);
 263         return -1;
 264 }
 265
 266 struct obd_device *class_uuid2obd(struct obd_uuid *uuid)
 267 {
 268         int dev = class_uuid2dev(uuid);
 269         if (dev < 0)
 270                 return NULL;
 271         return &obd_dev[dev];
 272 }
 273
 274 /* Search for a client OBD connected to tgt_uuid.  If grp_uuid is
 275    specified, then only the client with that uuid is returned,
 276    otherwise any client connected to the tgt is returned.
 277    If tgt_uuid is NULL, the lov with grp_uuid is returned. */
 278 struct obd_device *class_find_client_obd(struct obd_uuid *tgt_uuid,
 279                                          char *typ_name,
 280                                          struct obd_uuid *grp_uuid)
 281 {
 282         int i;
 283
 284         spin_lock(&obd_dev_lock);
 285         for (i = 0; i < MAX_OBD_DEVICES; i++) {
 286                 struct obd_device *obd = &obd_dev[i];
 287                 if (obd->obd_type == NULL)
 288                         continue;
 289                 if ((strncmp(obd->obd_type->typ_name, typ_name,
 290                              strlen(typ_name)) == 0)) {
 291                         struct client_obd *cli = &obd->u.cli;
 292                         struct obd_import *imp = cli->cl_import;
 293                         if (tgt_uuid == NULL) {
 294                                 LASSERT(grp_uuid);
 295                                 if (obd_uuid_equals(grp_uuid, &obd->obd_uuid)) {
 296                                         spin_unlock(&obd_dev_lock);
 297                                         return obd;
 298                                 }
 299                                 continue;
 300                         }
 301                         if (obd_uuid_equals(tgt_uuid, &imp->imp_target_uuid) &&
 302                             ((grp_uuid)? obd_uuid_equals(grp_uuid,
 303                                                          &obd->obd_uuid) : 1)) {
 304                                 spin_unlock(&obd_dev_lock);
 305                                 return obd;
 306                         }
 307                 }
 308         }
 309         spin_unlock(&obd_dev_lock);
 310         return NULL;
 311 }
 312
 313 /* Iterate the obd_device list looking devices have grp_uuid. Start
 314    searching at *next, and if a device is found, the next index to look
 315    it is saved in *next. If next is NULL, then the first matching device
 316    will always be returned. */
 317 struct obd_device *class_devices_in_group(struct obd_uuid *grp_uuid, int *next)
 318 {
 319         int i;
 320
 321         if (next == NULL)
 322                 i = 0;
 323         else if (*next >= 0 && *next < MAX_OBD_DEVICES)
 324                 i = *next;
 325         else
 326                 return NULL;
 327         spin_lock(&obd_dev_lock);
 328         for (; i < MAX_OBD_DEVICES; i++) {
 329                 struct obd_device *obd = &obd_dev[i];
 330                 if (obd->obd_type == NULL)
 331                         continue;
 332                 if (obd_uuid_equals(grp_uuid, &obd->obd_uuid)) {
 333                         if (next != NULL)
 334                                 *next = i+1;
 335                         spin_unlock(&obd_dev_lock);
 336                         return obd;
 337                 }
 338         }
 339
 340         spin_unlock(&obd_dev_lock);
 341         return NULL;
 342 }
 343
 344 void obd_cleanup_caches(void)
 345 {
 346         ENTRY;
 347         if (obdo_cachep) {
 348                 LASSERTF(kmem_cache_destroy(obdo_cachep) == 0,
 349                          "Cannot destory ll_obdo_cache\n");
 350                 obdo_cachep = NULL;
 351         }
 352         if (import_cachep) {
 353                 LASSERTF(kmem_cache_destroy(import_cachep) == 0,
 354                          "Cannot destory ll_import_cache\n");
 355                 import_cachep = NULL;
 356         }
 357         if (capa_cachep) {
 358                 LASSERTF(kmem_cache_destroy(capa_cachep) == 0,
 359                          "Cannot destory capa_cache\n");
 360                 capa_cachep = NULL;
 361         }
 362         EXIT;
 363 }
 364
 365 int obd_init_caches(void)
 366 {
 367         ENTRY;
 368         LASSERT(obdo_cachep == NULL);
 369         obdo_cachep = kmem_cache_create("ll_obdo_cache", sizeof(struct obdo),
 370                                         0, 0, NULL, NULL);
 371         if (!obdo_cachep)
 372                 GOTO(out, -ENOMEM);
 373
 374         LASSERT(import_cachep == NULL);
 375         import_cachep = kmem_cache_create("ll_import_cache",
 376                                           sizeof(struct obd_import),
 377                                           0, 0, NULL, NULL);
 378         if (!import_cachep)
 379                 GOTO(out, -ENOMEM);
 380
 381         LASSERT(capa_cachep == NULL);
 382         capa_cachep = kmem_cache_create("capa_cache",
 383                                         sizeof(struct obd_capa),
 384                                         0, 0, NULL, NULL);
 385         if (!capa_cachep)
 386                 GOTO(out, -ENOMEM);
 387
 388         RETURN(0);
 389  out:
 390         obd_cleanup_caches();
 391         RETURN(-ENOMEM);
 392
 393 }
 394
 395 /* map connection to client */
 396 struct obd_export *class_conn2export(struct lustre_handle *conn)
 397 {
 398         struct obd_export *export;
 399         ENTRY;
 400
 401         if (!conn) {
 402                 CDEBUG(D_CACHE, "looking for null handle\n");
 403                 RETURN(NULL);
 404         }
 405
 406         if (conn->cookie == -1) {  /* this means assign a new connection */
 407                 CDEBUG(D_CACHE, "want a new connection\n");
 408                 RETURN(NULL);
 409         }
 410
 411         CDEBUG(D_IOCTL, "looking for export cookie "LPX64"\n", conn->cookie);
 412         export = class_handle2object(conn->cookie);
 413         RETURN(export);
 414 }
 415
 416 struct obd_device *class_exp2obd(struct obd_export *exp)
 417 {
 418         if (exp)
 419                 return exp->exp_obd;
 420         return NULL;
 421 }
 422
 423 struct obd_device *class_conn2obd(struct lustre_handle *conn)
 424 {
 425         struct obd_export *export;
 426         export = class_conn2export(conn);
 427         if (export) {
 428                 struct obd_device *obd = export->exp_obd;
 429                 class_export_put(export);
 430                 return obd;
 431         }
 432         return NULL;
 433 }
 434
 435 struct obd_import *class_exp2cliimp(struct obd_export *exp)
 436 {
 437         struct obd_device *obd = exp->exp_obd;
 438         if (obd == NULL)
 439                 return NULL;
 440         return obd->u.cli.cl_import;
 441 }
 442
 443 struct obd_import *class_conn2cliimp(struct lustre_handle *conn)
 444 {
 445         struct obd_device *obd = class_conn2obd(conn);
 446         if (obd == NULL)
 447                 return NULL;
 448         return obd->u.cli.cl_import;
 449 }
 450
 451 /* Export management functions */
 452 static void export_handle_addref(void *export)
 453 {
 454         class_export_get(export);
 455 }
 456
 457 void __class_export_put(struct obd_export *exp)
 458 {
 459         if (atomic_dec_and_test(&exp->exp_refcount)) {
 460                 struct obd_device *obd = exp->exp_obd;
 461                 CDEBUG(D_IOCTL, "destroying export %p/%s\n", exp,
 462                        exp->exp_client_uuid.uuid);
 463
 464                 LASSERT(obd != NULL);
 465
 466                 /* "Local" exports (lctl, LOV->{mdc,osc}) have no connection. */
 467                 if (exp->exp_connection)
 468                         ptlrpc_put_connection_superhack(exp->exp_connection);
 469
 470                 LASSERT(list_empty(&exp->exp_outstanding_replies));
 471                 LASSERT(list_empty(&exp->exp_handle.h_link));
 472                 obd_destroy_export(exp);
 473
 474                 OBD_FREE(exp, sizeof(*exp));
 475                 if (obd->obd_set_up) {
 476                         atomic_dec(&obd->obd_refcount);
 477                         wake_up(&obd->obd_refcount_waitq);
 478                 } else {
 479                         CERROR("removing export %p from obd %s (%p) -- OBD "
 480                                "not set up (refcount = %d)\n", exp,
 481                                obd->obd_name, obd,
 482                                atomic_read(&obd->obd_refcount));
 483                 }
 484         }
 485 }
 486
 487 /* Creates a new export, adds it to the hash table, and returns a
 488  * pointer to it. The refcount is 2: one for the hash reference, and
 489  * one for the pointer returned by this function. */
 490 struct obd_export *class_new_export(struct obd_device *obd)
 491 {
 492         struct obd_export *export;
 493
 494         OBD_ALLOC(export, sizeof(*export));
 495         if (!export) {
 496                 CERROR("no memory! (minor %d)\n", obd->obd_minor);
 497                 return NULL;
 498         }
 499
 500         export->exp_conn_cnt = 0;
 501         atomic_set(&export->exp_refcount, 2);
 502         atomic_set(&export->exp_rpc_count, 0);
 503         export->exp_obd = obd;
 504         export->exp_flags = 0;
 505         INIT_LIST_HEAD(&export->exp_outstanding_replies);
 506         /* XXX this should be in LDLM init */
 507         INIT_LIST_HEAD(&export->exp_ldlm_data.led_held_locks);
 508         spin_lock_init(&export->exp_ldlm_data.led_lock);
 509
 510         INIT_LIST_HEAD(&export->exp_handle.h_link);
 511         class_handle_hash(&export->exp_handle, export_handle_addref);
 512         spin_lock_init(&export->exp_lock);
 513
 514         spin_lock(&obd->obd_dev_lock);
 515         LASSERT(!obd->obd_stopping); /* shouldn't happen, but might race */
 516         atomic_inc(&obd->obd_refcount);
 517         list_add(&export->exp_obd_chain, &export->exp_obd->obd_exports);
 518         export->exp_obd->obd_num_exports++;
 519         spin_unlock(&obd->obd_dev_lock);
 520         export->exp_connected = 1;
 521         obd_init_export(export);
 522         return export;
 523 }
 524
 525 void class_unlink_export(struct obd_export *exp)
 526 {
 527         class_handle_unhash(&exp->exp_handle);
 528
 529         spin_lock(&exp->exp_obd->obd_dev_lock);
 530         list_del_init(&exp->exp_obd_chain);
 531         exp->exp_obd->obd_num_exports--;
 532         spin_unlock(&exp->exp_obd->obd_dev_lock);
 533
 534         class_export_put(exp);
 535 }
 536
 537 /* Import management functions */
 538 static void import_handle_addref(void *import)
 539 {
 540         class_import_get(import);
 541 }
 542
 543 struct obd_import *class_import_get(struct obd_import *import)
 544 {
 545         atomic_inc(&import->imp_refcount);
 546         CDEBUG(D_IOCTL, "import %p refcount=%d\n", import,
 547                atomic_read(&import->imp_refcount));
 548         return import;
 549 }
 550
 551 void class_import_put(struct obd_import *import)
 552 {
 553         ENTRY;
 554
 555         CDEBUG(D_IOCTL, "import %p refcount=%d\n", import,
 556                atomic_read(&import->imp_refcount) - 1);
 557
 558         LASSERT(atomic_read(&import->imp_refcount) > 0);
 559         LASSERT(atomic_read(&import->imp_refcount) < 0x5a5a5a);
 560
 561         if (!atomic_dec_and_test(&import->imp_refcount)) {
 562                 EXIT;
 563                 return;
 564         }
 565
 566         CDEBUG(D_IOCTL, "destroying import %p\n", import);
 567
 568         if (import->imp_connection)
 569                 ptlrpc_put_connection_superhack(import->imp_connection);
 570
 571         LASSERT(!import->imp_sec);
 572         while (!list_empty(&import->imp_conn_list)) {
 573                 struct obd_import_conn *imp_conn;
 574
 575                 imp_conn = list_entry(import->imp_conn_list.next,
 576                                       struct obd_import_conn, oic_item);
 577                 list_del(&imp_conn->oic_item);
 578                 if (imp_conn->oic_conn)
 579                         ptlrpc_put_connection_superhack(imp_conn->oic_conn);
 580                 OBD_FREE(imp_conn, sizeof(*imp_conn));
 581         }
 582
 583         LASSERT(list_empty(&import->imp_handle.h_link));
 584         OBD_FREE(import, sizeof(*import));
 585         EXIT;
 586 }
 587
 588 struct obd_import *class_new_import(void)
 589 {
 590         struct obd_import *imp;
 591
 592         OBD_ALLOC(imp, sizeof(*imp));
 593         if (imp == NULL)
 594                 return NULL;
 595
 596         INIT_LIST_HEAD(&imp->imp_replay_list);
 597         INIT_LIST_HEAD(&imp->imp_sending_list);
 598         INIT_LIST_HEAD(&imp->imp_delayed_list);
 599         INIT_LIST_HEAD(&imp->imp_rawrpc_list);
 600         spin_lock_init(&imp->imp_lock);
 601         imp->imp_conn_cnt = 0;
 602         imp->imp_max_transno = 0;
 603         imp->imp_peer_committed_transno = 0;
 604         imp->imp_state = LUSTRE_IMP_NEW;
 605         init_waitqueue_head(&imp->imp_recovery_waitq);
 606
 607         atomic_set(&imp->imp_refcount, 2);
 608         atomic_set(&imp->imp_inflight, 0);
 609         atomic_set(&imp->imp_replay_inflight, 0);
 610         INIT_LIST_HEAD(&imp->imp_conn_list);
 611         INIT_LIST_HEAD(&imp->imp_handle.h_link);
 612         class_handle_hash(&imp->imp_handle, import_handle_addref);
 613         imp->imp_waiting_ping_reply = 0;
 614
 615         return imp;
 616 }
 617
 618 void class_destroy_import(struct obd_import *import)
 619 {
 620         LASSERT(import != NULL);
 621         LASSERT(import != LP_POISON);
 622
 623         class_handle_unhash(&import->imp_handle);
 624
 625         /* Abort any inflight DLM requests and NULL out their (about to be
 626          * freed) import. */
 627         /* Invalidate all requests on import, would be better to call
 628            ptlrpc_set_import_active(imp, 0); */
 629         import->imp_generation++;
 630         ptlrpc_abort_inflight_superhack(import);
 631
 632         class_import_put(import);
 633 }
 634
 635 /* A connection defines an export context in which preallocation can
 636    be managed. This releases the export pointer reference, and returns
 637    the export handle, so the export refcount is 1 when this function
 638    returns. */
 639 int class_connect(struct lustre_handle *conn, struct obd_device *obd,
 640                   struct obd_uuid *cluuid)
 641 {
 642         struct obd_export *export;
 643         LASSERT(conn != NULL);
 644         LASSERT(obd != NULL);
 645         LASSERT(cluuid != NULL);
 646         ENTRY;
 647
 648         export = class_new_export(obd);
 649         if (export == NULL)
 650                 RETURN(-ENOMEM);
 651
 652         conn->cookie = export->exp_handle.h_cookie;
 653         memcpy(&export->exp_client_uuid, cluuid,
 654                sizeof(export->exp_client_uuid));
 655         class_export_put(export);
 656
 657         CDEBUG(D_IOCTL, "connect: client %s, cookie "LPX64"\n",
 658                cluuid->uuid, conn->cookie);
 659         RETURN(0);
 660 }
 661
 662 /* This function removes two references from the export: one for the
 663  * hash entry and one for the export pointer passed in.  The export
 664  * pointer passed to this function is destroyed should not be used
 665  * again. */
 666 int class_disconnect(struct obd_export *export, unsigned long flags)
 667 {
 668         ENTRY;
 669
 670         if (export == NULL) {
 671                 fixme();
 672                 CDEBUG(D_IOCTL, "attempting to free NULL export %p\n", export);
 673                 RETURN(-EINVAL);
 674         }
 675
 676         /* XXX this shouldn't have to be here, but double-disconnect will crash
 677          * otherwise, and sometimes double-disconnect happens.  abort_recovery,
 678          * for example. */
 679         if (list_empty(&export->exp_handle.h_link))
 680                 RETURN(0);
 681
 682         CDEBUG(D_IOCTL, "disconnect: cookie "LPX64"\n",
 683                export->exp_handle.h_cookie);
 684
 685         if (export->exp_handle.h_cookie == LL_POISON) {
 686                 CERROR("disconnecting freed export %p, ignoring\n", export);
 687         } else {
 688                 class_unlink_export(export);
 689                 class_export_put(export);
 690         }
 691         RETURN(0);
 692 }
 693
 694 static void class_disconnect_export_list(struct list_head *list, unsigned long flags)
 695 {
 696         struct obd_export *fake_exp, *exp;
 697         struct lustre_handle fake_conn;
 698         int rc;
 699         ENTRY;
 700
 701         /* Move all of the exports from obd_exports to a work list, en masse. */
 702         /* It's possible that an export may disconnect itself, but
 703          * nothing else will be added to this list. */
 704         while(!list_empty(list)) {
 705                 exp = list_entry(list->next, struct obd_export, exp_obd_chain);
 706                 class_export_get(exp);
 707
 708                 if (obd_uuid_equals(&exp->exp_client_uuid,
 709                                     &exp->exp_obd->obd_uuid)) {
 710                         CDEBUG(D_HA,
 711                                "exp %p export uuid == obd uuid, don't discon\n",
 712                                exp);
 713                         /*
 714                          * need to delete this now so we don't end up pointing
 715                          * to work_list later when this export is cleaned up.
 716                          */
 717                         list_del_init(&exp->exp_obd_chain);
 718                         class_export_put(exp);
 719                         continue;
 720                 }
 721
 722                 fake_conn.cookie = exp->exp_handle.h_cookie;
 723                 fake_exp = class_conn2export(&fake_conn);
 724                 if (!fake_exp) {
 725                         class_export_put(exp);
 726                         continue;
 727                 }
 728
 729                 rc = obd_disconnect(fake_exp, flags);
 730                 class_export_put(exp);
 731                 if (rc) {
 732                         CDEBUG(D_HA, "disconnecting export %p failed: %d\n",
 733                                exp, rc);
 734                 } else {
 735                         CDEBUG(D_HA, "export %p disconnected\n", exp);
 736                 }
 737         }
 738         EXIT;
 739 }
 740
 741 void class_disconnect_exports(struct obd_device *obd, unsigned long flags)
 742 {
 743         struct list_head work_list;
 744         ENTRY;
 745
 746         /* Move all of the exports from obd_exports to a work list, en masse. */
 747         spin_lock(&obd->obd_dev_lock);
 748         list_add(&work_list, &obd->obd_exports);
 749         list_del_init(&obd->obd_exports);
 750         spin_unlock(&obd->obd_dev_lock);
 751
 752         CDEBUG(D_HA, "OBD device %d (%p) has exports, "
 753                "disconnecting them\n", obd->obd_minor, obd);
 754         class_disconnect_export_list(&work_list, flags);
 755         EXIT;
 756 }
 757
 758 /* Remove exports that have not completed recovery.
 759  */
 760 int class_disconnect_stale_exports(struct obd_device *obd,
 761                                    int (*test_export)(struct obd_export *),
 762                                    unsigned long flags)
 763 {
 764         char str[PTL_NALFMT_SIZE];
 765         struct list_head work_list;
 766         struct list_head *pos, *n;
 767         struct obd_export *exp;
 768         int cnt = 0;
 769         ENTRY;
 770
 771         INIT_LIST_HEAD(&work_list);
 772         spin_lock(&obd->obd_dev_lock);
 773         list_for_each_safe(pos, n, &obd->obd_exports) {
 774                 exp = list_entry(pos, struct obd_export, exp_obd_chain);
 775                 if (test_export(exp))
 776                         continue;
 777                 list_del(&exp->exp_obd_chain);
 778                 list_add(&exp->exp_obd_chain, &work_list);
 779                 cnt++;
 780                 CDEBUG(D_ERROR, "%s: disconnect stale client %s@%s\n",
 781                        obd->obd_name, exp->exp_client_uuid.uuid,
 782                        exp->exp_connection == NULL ? "<unknown>" :
 783                        ptlrpc_peernid2str(&exp->exp_connection->c_peer, str));
 784         }
 785         spin_unlock(&obd->obd_dev_lock);
 786
 787         CDEBUG(D_ERROR, "%s: disconnecting %d stale clients\n",
 788                obd->obd_name, cnt);
 789         class_disconnect_export_list(&work_list, flags);
 790         RETURN(cnt);
 791 }
 792
 793
 794
 795 int oig_init(struct obd_io_group **oig_out)
 796 {
 797         struct obd_io_group *oig;
 798         ENTRY;
 799
 800         OBD_ALLOC(oig, sizeof(*oig));
 801         if (oig == NULL)
 802                 RETURN(-ENOMEM);
 803
 804         spin_lock_init(&oig->oig_lock);
 805         oig->oig_rc = 0;
 806         oig->oig_pending = 0;
 807         atomic_set(&oig->oig_refcount, 1);
 808         init_waitqueue_head(&oig->oig_waitq);
 809         INIT_LIST_HEAD(&oig->oig_occ_list);
 810
 811         *oig_out = oig;
 812         RETURN(0);
 813 };
 814
 815 static inline void oig_grab(struct obd_io_group *oig)
 816 {
 817         atomic_inc(&oig->oig_refcount);
 818 }
 819
 820 void oig_release(struct obd_io_group *oig)
 821 {
 822         if (atomic_dec_and_test(&oig->oig_refcount))
 823                 OBD_FREE(oig, sizeof(*oig));
 824 }
 825
 826 void oig_add_one(struct obd_io_group *oig, struct oig_callback_context *occ)
 827 {
 828         unsigned long flags;
 829         CDEBUG(D_CACHE, "oig %p ready to roll\n", oig);
 830         spin_lock_irqsave(&oig->oig_lock, flags);
 831         oig->oig_pending++;
 832         if (occ != NULL)
 833                 list_add_tail(&occ->occ_oig_item, &oig->oig_occ_list);
 834         spin_unlock_irqrestore(&oig->oig_lock, flags);
 835         oig_grab(oig);
 836 }
 837
 838 void oig_complete_one(struct obd_io_group *oig,
 839                       struct oig_callback_context *occ, int rc)
 840 {
 841         unsigned long flags;
 842         wait_queue_head_t *wake = NULL;
 843         int old_rc;
 844
 845         spin_lock_irqsave(&oig->oig_lock, flags);
 846
 847         if (occ != NULL)
 848                 list_del_init(&occ->occ_oig_item);
 849
 850         old_rc = oig->oig_rc;
 851         if (oig->oig_rc == 0 && rc != 0)
 852                 oig->oig_rc = rc;
 853
 854         if (--oig->oig_pending <= 0)
 855                 wake = &oig->oig_waitq;
 856
 857         spin_unlock_irqrestore(&oig->oig_lock, flags);
 858
 859         CDEBUG(D_CACHE, "oig %p completed, rc %d -> %d via %d, %d now "
 860                         "pending (racey)\n", oig, old_rc, oig->oig_rc, rc,
 861                         oig->oig_pending);
 862         if (wake)
 863                 wake_up(wake);
 864         oig_release(oig);
 865 }
 866
 867 static int oig_done(struct obd_io_group *oig)
 868 {
 869         unsigned long flags;
 870         int rc = 0;
 871         spin_lock_irqsave(&oig->oig_lock, flags);
 872         if (oig->oig_pending <= 0)
 873                 rc = 1;
 874         spin_unlock_irqrestore(&oig->oig_lock, flags);
 875         return rc;
 876 }
 877
 878 static void interrupted_oig(void *data)
 879 {
 880         struct obd_io_group *oig = data;
 881         struct oig_callback_context *occ;
 882         unsigned long flags;
 883
 884         spin_lock_irqsave(&oig->oig_lock, flags);
 885         /* We need to restart the processing each time we drop the lock, as
 886          * it is possible other threads called oig_complete_one() to remove
 887          * an entry elsewhere in the list while we dropped lock.  We need to
 888          * drop the lock because osc_ap_completion() calls oig_complete_one()
 889          * which re-gets this lock ;-) as well as a lock ordering issue. */
 890 restart:
 891         list_for_each_entry(occ, &oig->oig_occ_list, occ_oig_item) {
 892                 if (occ->interrupted)
 893                         continue;
 894                 occ->interrupted = 1;
 895                 spin_unlock_irqrestore(&oig->oig_lock, flags);
 896                 occ->occ_interrupted(occ);
 897                 spin_lock_irqsave(&oig->oig_lock, flags);
 898                 goto restart;
 899         }
 900         spin_unlock_irqrestore(&oig->oig_lock, flags);
 901 }
 902
 903 int oig_wait(struct obd_io_group *oig)
 904 {
 905         struct l_wait_info lwi = LWI_INTR(interrupted_oig, oig);
 906         int rc;
 907
 908         CDEBUG(D_CACHE, "waiting for oig %p\n", oig);
 909
 910         do {
 911                 rc = l_wait_event(oig->oig_waitq, oig_done(oig), &lwi);
 912                 LASSERTF(rc == 0 || rc == -EINTR, "rc: %d\n", rc);
 913                 /* we can't continue until the oig has emptied and stopped
 914                  * referencing state that the caller will free upon return */
 915                 if (rc == -EINTR)
 916                         lwi = (struct l_wait_info){ 0, };
 917         } while (rc == -EINTR);
 918
 919         LASSERTF(oig->oig_pending == 0,
 920                  "exiting oig_wait(oig = %p) with %d pending\n", oig,
 921                  oig->oig_pending);
 922
 923         CDEBUG(D_CACHE, "done waiting on oig %p rc %d\n", oig, oig->oig_rc);
 924         return oig->oig_rc;
 925 }