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 #else
  33 #include <liblustre.h>
  34 #include <linux/obd_class.h>
  35 #include <linux/obd.h>
  36 #endif
  37 #include <linux/lprocfs_status.h>
  38
  39 extern struct list_head obd_types;
  40 static spinlock_t obd_types_lock = SPIN_LOCK_UNLOCKED;
  41 kmem_cache_t *obdo_cachep = NULL;
  42 kmem_cache_t *import_cachep = NULL;
  43
  44 int (*ptlrpc_put_connection_superhack)(struct ptlrpc_connection *c);
  45 void (*ptlrpc_abort_inflight_superhack)(struct obd_import *imp);
  46
  47 struct obd_uuid lctl_fake_uuid = { .uuid = "OBD_CLASS_UUID" };
  48
  49 /*
  50  * support functions: we could use inter-module communication, but this
  51  * is more portable to other OS's
  52  */
  53 static struct obd_type *class_search_type(char *name)
  54 {
  55         struct list_head *tmp;
  56         struct obd_type *type;
  57
  58         spin_lock(&obd_types_lock);
  59         list_for_each(tmp, &obd_types) {
  60                 type = list_entry(tmp, struct obd_type, typ_chain);
  61                 if (strlen(type->typ_name) == strlen(name) &&
  62                     strcmp(type->typ_name, name) == 0) {
  63                         spin_unlock(&obd_types_lock);
  64                         return type;
  65                 }
  66         }
  67         spin_unlock(&obd_types_lock);
  68         return NULL;
  69 }
  70
  71 struct obd_type *class_get_type(char *name)
  72 {
  73         struct obd_type *type = class_search_type(name);
  74
  75 #ifdef CONFIG_KMOD
  76         if (!type) {
  77                 if (!request_module(name)) {
  78                         CDEBUG(D_INFO, "Loaded module '%s'\n", name);
  79                         type = class_search_type(name);
  80                 } else
  81                         CDEBUG(D_INFO, "Can't load module '%s'\n", name);
  82         }
  83 #endif
  84         if (type)
  85                 __MOD_INC_USE_COUNT(type->typ_ops->o_owner);
  86         return type;
  87 }
  88
  89 void class_put_type(struct obd_type *type)
  90 {
  91         LASSERT(type);
  92         __MOD_DEC_USE_COUNT(type->typ_ops->o_owner);
  93 }
  94
  95 int class_register_type(struct obd_ops *ops, struct lprocfs_vars *vars,
  96                         char *name)
  97 {
  98         struct obd_type *type;
  99         int rc = 0;
 100         ENTRY;
 101
 102         LASSERT(strnlen(name, 1024) < 1024);    /* sanity check */
 103
 104         if (class_search_type(name)) {
 105                 CDEBUG(D_IOCTL, "Type %s already registered\n", name);
 106                 RETURN(-EEXIST);
 107         }
 108
 109         rc = -ENOMEM;
 110         OBD_ALLOC(type, sizeof(*type));
 111         if (type == NULL)
 112                 RETURN(rc);
 113
 114         OBD_ALLOC(type->typ_ops, sizeof(*type->typ_ops));
 115         OBD_ALLOC(type->typ_name, strlen(name) + 1);
 116         if (type->typ_ops == NULL || type->typ_name == NULL)
 117                 GOTO (failed, rc);
 118
 119         *(type->typ_ops) = *ops;
 120         strcpy(type->typ_name, name);
 121
 122         type->typ_procroot = lprocfs_register(type->typ_name, proc_lustre_root,
 123                                               vars, type);
 124         if (IS_ERR(type->typ_procroot)) {
 125                 rc = PTR_ERR(type->typ_procroot);
 126                 type->typ_procroot = NULL;
 127                 GOTO (failed, rc);
 128         }
 129
 130         spin_lock(&obd_types_lock);
 131         list_add(&type->typ_chain, &obd_types);
 132         spin_unlock(&obd_types_lock);
 133
 134         RETURN (0);
 135
 136  failed:
 137         if (type->typ_ops != NULL)
 138                 OBD_FREE(type->typ_name, strlen(name) + 1);
 139         if (type->typ_ops != NULL)
 140                 OBD_FREE (type->typ_ops, sizeof (*type->typ_ops));
 141         RETURN(rc);
 142 }
 143
 144 int class_unregister_type(char *name)
 145 {
 146         struct obd_type *type = class_search_type(name);
 147         ENTRY;
 148
 149         if (!type) {
 150                 CERROR("unknown obd type\n");
 151                 RETURN(-EINVAL);
 152         }
 153
 154         if (type->typ_refcnt) {
 155                 CERROR("type %s has refcount (%d)\n", name, type->typ_refcnt);
 156                 /* This is a bad situation, let's make the best of it */
 157                 /* Remove ops, but leave the name for debugging */
 158                 OBD_FREE(type->typ_ops, sizeof(*type->typ_ops));
 159                 RETURN(-EBUSY);
 160         }
 161
 162         if (type->typ_procroot) {
 163                 lprocfs_remove(type->typ_procroot);
 164                 type->typ_procroot = NULL;
 165         }
 166
 167         spin_lock(&obd_types_lock);
 168         list_del(&type->typ_chain);
 169         spin_unlock(&obd_types_lock);
 170         OBD_FREE(type->typ_name, strlen(name) + 1);
 171         if (type->typ_ops != NULL)
 172                 OBD_FREE(type->typ_ops, sizeof(*type->typ_ops));
 173         OBD_FREE(type, sizeof(*type));
 174         RETURN(0);
 175 } /* class_unregister_type */
 176
 177 int class_name2dev(char *name)
 178 {
 179         int i;
 180
 181         if (!name)
 182                 return -1;
 183
 184         for (i = 0; i < MAX_OBD_DEVICES; i++) {
 185                 struct obd_device *obd = &obd_dev[i];
 186                 if (obd->obd_name && strcmp(name, obd->obd_name) == 0)
 187                         return i;
 188         }
 189
 190         return -1;
 191 }
 192
 193 int class_uuid2dev(struct obd_uuid *uuid)
 194 {
 195         int i;
 196
 197         for (i = 0; i < MAX_OBD_DEVICES; i++) {
 198                 struct obd_device *obd = &obd_dev[i];
 199                 if (obd_uuid_equals(uuid, &obd->obd_uuid))
 200                         return i;
 201         }
 202
 203         return -1;
 204 }
 205
 206 struct obd_device *class_uuid2obd(struct obd_uuid *uuid)
 207 {
 208         int i;
 209
 210         for (i = 0; i < MAX_OBD_DEVICES; i++) {
 211                 struct obd_device *obd = &obd_dev[i];
 212                 if (obd_uuid_equals(uuid, &obd->obd_uuid))
 213                         return obd;
 214         }
 215
 216         return NULL;
 217 }
 218
 219 void obd_cleanup_caches(void)
 220 {
 221         int rc;
 222         ENTRY;
 223         if (obdo_cachep) {
 224                 rc = kmem_cache_destroy(obdo_cachep);
 225                 if (rc)
 226                         CERROR("Cannot destory ll_obdo_cache\n");
 227                 obdo_cachep = NULL;
 228         }
 229         if (import_cachep) {
 230                 rc = kmem_cache_destroy(import_cachep);
 231                 if (rc)
 232                         CERROR("Cannot destory ll_import_cache\n");
 233                 import_cachep = NULL;
 234         }
 235         EXIT;
 236 }
 237
 238 int obd_init_caches(void)
 239 {
 240         ENTRY;
 241         LASSERT(obdo_cachep == NULL);
 242         obdo_cachep = kmem_cache_create("ll_obdo_cache", sizeof(struct obdo),
 243                                         0, 0, NULL, NULL);
 244         if (!obdo_cachep)
 245                 GOTO(out, -ENOMEM);
 246
 247         LASSERT(import_cachep == NULL);
 248         import_cachep = kmem_cache_create("ll_import_cache",
 249                                           sizeof(struct obd_import),
 250                                           0, 0, NULL, NULL);
 251         if (!import_cachep)
 252                 GOTO(out, -ENOMEM);
 253
 254         RETURN(0);
 255  out:
 256         obd_cleanup_caches();
 257         RETURN(-ENOMEM);
 258
 259 }
 260
 261 /* map connection to client */
 262 struct obd_export *class_conn2export(struct lustre_handle *conn)
 263 {
 264         struct obd_export *export;
 265         ENTRY;
 266
 267         if (!conn) {
 268                 CDEBUG(D_CACHE, "looking for null handle\n");
 269                 RETURN(NULL);
 270         }
 271
 272         if (conn->cookie == -1) {  /* this means assign a new connection */
 273                 CDEBUG(D_CACHE, "want a new connection\n");
 274                 RETURN(NULL);
 275         }
 276
 277         CDEBUG(D_IOCTL, "looking for export cookie "LPX64"\n", conn->cookie);
 278         export = class_handle2object(conn->cookie);
 279         RETURN(export);
 280 }
 281
 282 struct obd_device *class_conn2obd(struct lustre_handle *conn)
 283 {
 284         struct obd_export *export;
 285         export = class_conn2export(conn);
 286         if (export) {
 287                 struct obd_device *obd = export->exp_obd;
 288                 class_export_put(export);
 289                 return obd;
 290         }
 291         return NULL;
 292 }
 293
 294 struct obd_import *class_conn2cliimp(struct lustre_handle *conn)
 295 {
 296         return class_conn2obd(conn)->u.cli.cl_import;
 297 }
 298
 299 struct obd_import *class_conn2ldlmimp(struct lustre_handle *conn)
 300 {
 301         struct obd_export *export;
 302         export = class_conn2export(conn);
 303         if (export) {
 304                 struct obd_import *imp = export->exp_ldlm_data.led_import;
 305                 class_export_put(export);
 306                 return imp;
 307         }
 308         fixme();
 309         return NULL;
 310 }
 311
 312 /* Export management functions */
 313 static void export_handle_addref(void *export)
 314 {
 315         class_export_get(export);
 316 }
 317
 318 struct obd_export *class_export_get(struct obd_export *exp)
 319 {
 320         atomic_inc(&exp->exp_refcount);
 321         CDEBUG(D_INFO, "GETting export %p : new refcount %d\n", exp,
 322                atomic_read(&exp->exp_refcount));
 323         return exp;
 324 }
 325
 326 void class_export_put(struct obd_export *exp)
 327 {
 328         ENTRY;
 329
 330         CDEBUG(D_INFO, "PUTting export %p : new refcount %d\n", exp,
 331                atomic_read(&exp->exp_refcount) - 1);
 332         LASSERT(atomic_read(&exp->exp_refcount) > 0);
 333         LASSERT(atomic_read(&exp->exp_refcount) < 0x5a5a5a);
 334         if (atomic_dec_and_test(&exp->exp_refcount)) {
 335                 struct obd_device *obd = exp->exp_obd;
 336                 CDEBUG(D_IOCTL, "destroying export %p/%s\n", exp,
 337                        exp->exp_client_uuid.uuid);
 338
 339                 LASSERT(obd != NULL);
 340
 341                 /* "Local" exports (lctl, LOV->{mdc,osc}) have no connection. */
 342                 if (exp->exp_connection)
 343                         ptlrpc_put_connection_superhack(exp->exp_connection);
 344
 345                 LASSERT(list_empty(&exp->exp_handle.h_link));
 346
 347                 obd_destroy_export(exp);
 348
 349                 OBD_FREE(exp, sizeof(*exp));
 350                 atomic_dec(&obd->obd_refcount);
 351                 wake_up(&obd->obd_refcount_waitq);
 352         }
 353         EXIT;
 354 }
 355
 356 struct obd_export *class_new_export(struct obd_device *obddev)
 357 {
 358         struct obd_export *export;
 359
 360         OBD_ALLOC(export, sizeof(*export));
 361         if (!export) {
 362                 CERROR("no memory! (minor %d)\n", obddev->obd_minor);
 363                 return NULL;
 364         }
 365
 366         atomic_set(&export->exp_refcount, 2);
 367         export->exp_obd = obddev;
 368         /* XXX this should be in LDLM init */
 369         INIT_LIST_HEAD(&export->exp_ldlm_data.led_held_locks);
 370
 371         INIT_LIST_HEAD(&export->exp_handle.h_link);
 372         class_handle_hash(&export->exp_handle, export_handle_addref);
 373         spin_lock_init(&export->exp_lock);
 374
 375         spin_lock(&obddev->obd_dev_lock);
 376         LASSERT(!obddev->obd_stopping); /* shouldn't happen, but might race */
 377         atomic_inc(&obddev->obd_refcount);
 378         list_add(&export->exp_obd_chain, &export->exp_obd->obd_exports);
 379         spin_unlock(&obddev->obd_dev_lock);
 380         return export;
 381 }
 382
 383 void class_unlink_export(struct obd_export *exp)
 384 {
 385         class_handle_unhash(&exp->exp_handle);
 386
 387         spin_lock(&exp->exp_obd->obd_dev_lock);
 388         list_del_init(&exp->exp_obd_chain);
 389         spin_unlock(&exp->exp_obd->obd_dev_lock);
 390
 391         class_export_put(exp);
 392 }
 393
 394 /* Import management functions */
 395 static void import_handle_addref(void *import)
 396 {
 397         class_import_get(import);
 398 }
 399
 400 struct obd_import *class_import_get(struct obd_import *import)
 401 {
 402         atomic_inc(&import->imp_refcount);
 403         CDEBUG(D_IOCTL, "import %p refcount=%d\n", import,
 404                atomic_read(&import->imp_refcount));
 405         return import;
 406 }
 407
 408 void class_import_put(struct obd_import *import)
 409 {
 410         ENTRY;
 411
 412         CDEBUG(D_IOCTL, "import %p refcount=%d\n", import,
 413                atomic_read(&import->imp_refcount) - 1);
 414
 415         LASSERT(atomic_read(&import->imp_refcount) > 0);
 416         LASSERT(atomic_read(&import->imp_refcount) < 0x5a5a5a);
 417         if (!atomic_dec_and_test(&import->imp_refcount)) {
 418                 EXIT;
 419                 return;
 420         }
 421
 422         CDEBUG(D_IOCTL, "destroying import %p\n", import);
 423
 424         ptlrpc_put_connection_superhack(import->imp_connection);
 425
 426         LASSERT(list_empty(&import->imp_handle.h_link));
 427         OBD_FREE(import, sizeof(*import));
 428         EXIT;
 429 }
 430
 431 struct obd_import *class_new_import(void)
 432 {
 433         struct obd_import *imp;
 434
 435         OBD_ALLOC(imp, sizeof(*imp));
 436         if (imp == NULL)
 437                 return NULL;
 438
 439         INIT_LIST_HEAD(&imp->imp_replay_list);
 440         INIT_LIST_HEAD(&imp->imp_sending_list);
 441         INIT_LIST_HEAD(&imp->imp_delayed_list);
 442         spin_lock_init(&imp->imp_lock);
 443         imp->imp_max_transno = 0;
 444         imp->imp_peer_committed_transno = 0;
 445
 446         atomic_set(&imp->imp_refcount, 2);
 447         INIT_LIST_HEAD(&imp->imp_handle.h_link);
 448         class_handle_hash(&imp->imp_handle, import_handle_addref);
 449
 450         return imp;
 451 }
 452
 453 void class_destroy_import(struct obd_import *import)
 454 {
 455         LASSERT(import != NULL);
 456
 457         class_handle_unhash(&import->imp_handle);
 458
 459         /* Abort any inflight DLM requests and NULL out their (about to be
 460          * freed) import. */
 461         ptlrpc_abort_inflight_superhack(import);
 462
 463         class_import_put(import);
 464 }
 465
 466 /* a connection defines an export context in which preallocation can
 467    be managed. */
 468 int class_connect(struct lustre_handle *exporth, struct obd_device *obd,
 469                   struct obd_uuid *cluuid)
 470 {
 471         struct obd_export *export;
 472         LASSERT(exporth != NULL);
 473         LASSERT(obd != NULL);
 474         LASSERT(cluuid != NULL);
 475
 476         export = class_new_export(obd);
 477         if (export == NULL)
 478                 return -ENOMEM;
 479
 480         exporth->cookie = export->exp_handle.h_cookie;
 481         memcpy(&export->exp_client_uuid, cluuid,
 482                sizeof(export->exp_client_uuid));
 483         class_export_put(export);
 484
 485         CDEBUG(D_IOCTL, "connect: client %s, cookie "LPX64"\n",
 486                cluuid->uuid, exporth->cookie);
 487         return 0;
 488 }
 489
 490 int class_disconnect(struct lustre_handle *conn, int failover)
 491 {
 492         struct obd_export *export = class_conn2export(conn);
 493         ENTRY;
 494
 495         if (export == NULL) {
 496                 fixme();
 497                 CDEBUG(D_IOCTL, "disconnect: attempting to free "
 498                        "nonexistent client "LPX64"\n", conn->cookie);
 499                 RETURN(-EINVAL);
 500         }
 501
 502         CDEBUG(D_IOCTL, "disconnect: cookie "LPX64"\n", conn->cookie);
 503
 504         class_unlink_export(export);
 505         class_export_put(export);
 506         RETURN(0);
 507 }
 508
 509 void class_disconnect_exports(struct obd_device *obd, int failover)
 510 {
 511         int rc;
 512         struct list_head *tmp, *n, work_list;
 513         struct lustre_handle fake_conn;
 514         ENTRY;
 515
 516         /* Move all of the exports from obd_exports to a work list, en masse. */
 517         spin_lock(&obd->obd_dev_lock);
 518         list_add(&work_list, &obd->obd_exports);
 519         list_del_init(&obd->obd_exports);
 520         spin_unlock(&obd->obd_dev_lock);
 521
 522         CDEBUG(D_IOCTL, "OBD device %d (%p) has exports, "
 523                "disconnecting them\n", obd->obd_minor, obd);
 524         list_for_each_safe(tmp, n, &work_list) {
 525                 struct obd_export *exp = list_entry(tmp, struct obd_export,
 526                                                     exp_obd_chain);
 527
 528                 class_export_get(exp);
 529                 fake_conn.cookie = exp->exp_handle.h_cookie;
 530                 rc = obd_disconnect(&fake_conn, failover);
 531                 /* exports created from last_rcvd data, and "fake"
 532                    exports created by lctl don't have an import */
 533                 if (exp->exp_ldlm_data.led_import != NULL)
 534                         class_destroy_import(exp->exp_ldlm_data.led_import);
 535                 class_export_put(exp);
 536
 537                 if (rc) {
 538                         CDEBUG(D_IOCTL, "disconnecting export %p failed: %d\n",
 539                                exp, rc);
 540                 } else {
 541                         CDEBUG(D_IOCTL, "export %p disconnected\n", exp);
 542                 }
 543         }
 544         EXIT;
 545 }