lustre/obdecho/echo.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  *   Author: Peter Braam <braam@clusterfs.com>
   6  *   Author: Andreas Dilger <adilger@clusterfs.com>
   7  *
   8  *   This file is part of the Lustre file system, http://www.lustre.org
   9  *   Lustre is a trademark of Cluster File Systems, Inc.
  10  *
  11  *   You may have signed or agreed to another license before downloading
  12  *   this software.  If so, you are bound by the terms and conditions
  13  *   of that agreement, and the following does not apply to you.  See the
  14  *   LICENSE file included with this distribution for more information.
  15  *
  16  *   If you did not agree to a different license, then this copy of Lustre
  17  *   is open source software; you can redistribute it and/or modify it
  18  *   under the terms of version 2 of the GNU General Public License as
  19  *   published by the Free Software Foundation.
  20  *
  21  *   In either case, Lustre is distributed in the hope that it will be
  22  *   useful, but WITHOUT ANY WARRANTY; without even the implied warranty
  23  *   of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  24  *   license text for more details.
  25  */
  26
  27 #ifndef EXPORT_SYMTAB
  28 # define EXPORT_SYMTAB
  29 #endif
  30
  31 #define DEBUG_SUBSYSTEM S_ECHO
  32
  33 #include <obd_support.h>
  34 #include <obd_class.h>
  35 #include <obd_echo.h>
  36 #include <lustre_debug.h>
  37 #include <lustre_dlm.h>
  38 #include <lprocfs_status.h>
  39
  40 #define ECHO_INIT_OBJID      0x1000000000000000ULL
  41 #define ECHO_HANDLE_MAGIC    0xabcd0123fedc9876ULL
  42
  43 #define ECHO_PERSISTENT_PAGES (ECHO_PERSISTENT_SIZE >> CFS_PAGE_SHIFT)
  44 static cfs_page_t *echo_persistent_pages[ECHO_PERSISTENT_PAGES];
  45
  46 enum {
  47         LPROC_ECHO_READ_BYTES = 1,
  48         LPROC_ECHO_WRITE_BYTES = 2,
  49         LPROC_ECHO_LAST = LPROC_ECHO_WRITE_BYTES +1
  50 };
  51
  52 static int echo_connect(const struct lu_env *env,
  53                         struct lustre_handle *conn, struct obd_device *obd,
  54                         struct obd_uuid *cluuid, struct obd_connect_data *data,
  55                         void *localdata)
  56 {
  57         data->ocd_connect_flags &= ECHO_CONNECT_SUPPORTED;
  58         return class_connect(conn, obd, cluuid);
  59 }
  60
  61 static int echo_disconnect(struct obd_export *exp)
  62 {
  63         LASSERT (exp != NULL);
  64
  65         ldlm_cancel_locks_for_export(exp);
  66
  67         /* complete all outstanding replies */
  68         spin_lock(&exp->exp_lock);
  69         while (!list_empty(&exp->exp_outstanding_replies)) {
  70                 struct ptlrpc_reply_state *rs =
  71                         list_entry(exp->exp_outstanding_replies.next,
  72                                    struct ptlrpc_reply_state, rs_exp_list);
  73                 struct ptlrpc_service *svc = rs->rs_service;
  74
  75                 spin_lock(&svc->srv_lock);
  76                 list_del_init(&rs->rs_exp_list);
  77                 ptlrpc_schedule_difficult_reply(rs);
  78                 spin_unlock(&svc->srv_lock);
  79         }
  80         spin_unlock(&exp->exp_lock);
  81
  82         return class_disconnect(exp);
  83 }
  84
  85 static int echo_destroy_export(struct obd_export *exp)
  86 {
  87         ENTRY;
  88
  89         target_destroy_export(exp);
  90
  91         RETURN(0);
  92 }
  93
  94  static __u64 echo_next_id(struct obd_device *obddev)
  95 {
  96         obd_id id;
  97
  98         spin_lock(&obddev->u.echo.eo_lock);
  99         id = ++obddev->u.echo.eo_lastino;
 100         spin_unlock(&obddev->u.echo.eo_lock);
 101
 102         return id;
 103 }
 104
 105 int echo_create(struct obd_export *exp, struct obdo *oa,
 106                 struct lov_stripe_md **ea, struct obd_trans_info *oti)
 107 {
 108         struct obd_device *obd = class_exp2obd(exp);
 109
 110         if (!obd) {
 111                 CERROR("invalid client cookie "LPX64"\n",
 112                        exp->exp_handle.h_cookie);
 113                 return -EINVAL;
 114         }
 115
 116         if (!(oa->o_mode && S_IFMT)) {
 117                 CERROR("echo obd: no type!\n");
 118                 return -ENOENT;
 119         }
 120
 121         if (!(oa->o_valid & OBD_MD_FLTYPE)) {
 122                 CERROR("invalid o_valid "LPX64"\n", oa->o_valid);
 123                 return -EINVAL;
 124         }
 125
 126         oa->o_id = echo_next_id(obd);
 127         oa->o_valid = OBD_MD_FLID;
 128
 129         return 0;
 130 }
 131
 132 int echo_destroy(struct obd_export *exp, struct obdo *oa,
 133                  struct lov_stripe_md *ea, struct obd_trans_info *oti,
 134                  struct obd_export *md_exp)
 135 {
 136         struct obd_device *obd = class_exp2obd(exp);
 137
 138         ENTRY;
 139         if (!obd) {
 140                 CERROR("invalid client cookie "LPX64"\n",
 141                        exp->exp_handle.h_cookie);
 142                 RETURN(-EINVAL);
 143         }
 144
 145         if (!(oa->o_valid & OBD_MD_FLID)) {
 146                 CERROR("obdo missing FLID valid flag: "LPX64"\n", oa->o_valid);
 147                 RETURN(-EINVAL);
 148         }
 149
 150         if (oa->o_id > obd->u.echo.eo_lastino || oa->o_id < ECHO_INIT_OBJID) {
 151                 CERROR("bad destroy objid: "LPX64"\n", oa->o_id);
 152                 RETURN(-EINVAL);
 153         }
 154
 155         RETURN(0);
 156 }
 157
 158 static int echo_getattr(struct obd_export *exp, struct obd_info *oinfo)
 159 {
 160         struct obd_device *obd = class_exp2obd(exp);
 161         obd_id id = oinfo->oi_oa->o_id;
 162
 163         ENTRY;
 164         if (!obd) {
 165                 CERROR("invalid client cookie "LPX64"\n",
 166                        exp->exp_handle.h_cookie);
 167                 RETURN(-EINVAL);
 168         }
 169
 170         if (!(oinfo->oi_oa->o_valid & OBD_MD_FLID)) {
 171                 CERROR("obdo missing FLID valid flag: "LPX64"\n",
 172                        oinfo->oi_oa->o_valid);
 173                 RETURN(-EINVAL);
 174         }
 175
 176         obdo_cpy_md(oinfo->oi_oa, &obd->u.echo.eo_oa, oinfo->oi_oa->o_valid);
 177         oinfo->oi_oa->o_id = id;
 178
 179         RETURN(0);
 180 }
 181
 182 static int echo_setattr(struct obd_export *exp, struct obd_info *oinfo,
 183                         struct obd_trans_info *oti)
 184 {
 185         struct obd_device *obd = class_exp2obd(exp);
 186
 187         ENTRY;
 188         if (!obd) {
 189                 CERROR("invalid client cookie "LPX64"\n",
 190                        exp->exp_handle.h_cookie);
 191                 RETURN(-EINVAL);
 192         }
 193
 194         if (!(oinfo->oi_oa->o_valid & OBD_MD_FLID)) {
 195                 CERROR("obdo missing FLID valid flag: "LPX64"\n",
 196                        oinfo->oi_oa->o_valid);
 197                 RETURN(-EINVAL);
 198         }
 199
 200         memcpy(&obd->u.echo.eo_oa, oinfo->oi_oa, sizeof(*oinfo->oi_oa));
 201
 202         if (oinfo->oi_oa->o_id & 4) {
 203                 /* Save lock to force ACKed reply */
 204                 ldlm_lock_addref (&obd->u.echo.eo_nl_lock, LCK_NL);
 205                 oti->oti_ack_locks[0].mode = LCK_NL;
 206                 oti->oti_ack_locks[0].lock = obd->u.echo.eo_nl_lock;
 207         }
 208
 209         RETURN(0);
 210 }
 211
 212 static void
 213 echo_page_debug_setup(cfs_page_t *page, int rw, obd_id id,
 214                       __u64 offset, int len)
 215 {
 216         int   page_offset = offset & ~CFS_PAGE_MASK;
 217         char *addr        = ((char *)cfs_kmap(page)) + page_offset;
 218
 219         if (len % OBD_ECHO_BLOCK_SIZE != 0)
 220                 CERROR("Unexpected block size %d\n", len);
 221
 222         while (len > 0) {
 223                 if (rw & OBD_BRW_READ)
 224                         block_debug_setup(addr, OBD_ECHO_BLOCK_SIZE,
 225                                           offset, id);
 226                 else
 227                         block_debug_setup(addr, OBD_ECHO_BLOCK_SIZE,
 228                                           0xecc0ecc0ecc0ecc0ULL,
 229                                           0xecc0ecc0ecc0ecc0ULL);
 230
 231                 addr   += OBD_ECHO_BLOCK_SIZE;
 232                 offset += OBD_ECHO_BLOCK_SIZE;
 233                 len    -= OBD_ECHO_BLOCK_SIZE;
 234         }
 235
 236         cfs_kunmap(page);
 237 }
 238
 239 static int
 240 echo_page_debug_check(cfs_page_t *page, obd_id id,
 241                       __u64 offset, int len)
 242 {
 243         int   page_offset = offset & ~CFS_PAGE_MASK;
 244         char *addr        = ((char *)cfs_kmap(page)) + page_offset;
 245         int   rc          = 0;
 246         int   rc2;
 247
 248         if (len % OBD_ECHO_BLOCK_SIZE != 0)
 249                 CERROR("Unexpected block size %d\n", len);
 250
 251         while (len > 0) {
 252                 rc2 = block_debug_check("echo", addr, OBD_ECHO_BLOCK_SIZE,
 253                                         offset, id);
 254
 255                 if (rc2 != 0 && rc == 0)
 256                         rc = rc2;
 257
 258                 addr   += OBD_ECHO_BLOCK_SIZE;
 259                 offset += OBD_ECHO_BLOCK_SIZE;
 260                 len    -= OBD_ECHO_BLOCK_SIZE;
 261         }
 262
 263         cfs_kunmap(page);
 264
 265         return (rc);
 266 }
 267
 268 /* This allows us to verify that desc_private is passed unmolested */
 269 #define DESC_PRIV 0x10293847
 270
 271 int echo_preprw(int cmd, struct obd_export *export, struct obdo *oa,
 272                 int objcount, struct obd_ioobj *obj, int niocount,
 273                 struct niobuf_remote *nb, struct niobuf_local *res,
 274                 struct obd_trans_info *oti, struct lustre_capa *unused)
 275 {
 276         struct obd_device *obd;
 277         struct niobuf_local *r = res;
 278         int tot_bytes = 0;
 279         int rc = 0;
 280         int i;
 281         ENTRY;
 282
 283         obd = export->exp_obd;
 284         if (obd == NULL)
 285                 RETURN(-EINVAL);
 286
 287         /* Temp fix to stop falling foul of osc_announce_cached() */
 288         oa->o_valid &= ~(OBD_MD_FLBLOCKS | OBD_MD_FLGRANT);
 289
 290         memset(res, 0, sizeof(*res) * niocount);
 291
 292         CDEBUG(D_PAGE, "%s %d obdos with %d IOs\n",
 293                cmd == OBD_BRW_READ ? "reading" : "writing", objcount, niocount);
 294
 295         if (oti)
 296                 oti->oti_handle = (void *)DESC_PRIV;
 297
 298         for (i = 0; i < objcount; i++, obj++) {
 299                 int gfp_mask = (obj->ioo_id & 1) ? CFS_ALLOC_HIGHUSER : CFS_ALLOC_STD;
 300                 int ispersistent = obj->ioo_id == ECHO_PERSISTENT_OBJID;
 301                 int debug_setup = (!ispersistent &&
 302                                    (oa->o_valid & OBD_MD_FLFLAGS) != 0 &&
 303                                    (oa->o_flags & OBD_FL_DEBUG_CHECK) != 0);
 304                 int j;
 305
 306                 for (j = 0 ; j < obj->ioo_bufcnt ; j++, nb++, r++) {
 307
 308                         if (ispersistent &&
 309                             (nb->offset >> CFS_PAGE_SHIFT) < ECHO_PERSISTENT_PAGES) {
 310                                 r->page = echo_persistent_pages[nb->offset >>
 311                                                                 CFS_PAGE_SHIFT];
 312                                 /* Take extra ref so __free_pages() can be called OK */
 313                                 cfs_get_page (r->page);
 314                         } else {
 315                                 OBD_PAGE_ALLOC(r->page, gfp_mask);
 316                                 if (r->page == NULL) {
 317                                         CERROR("can't get page %u/%u for id "
 318                                                LPU64"\n",
 319                                                j, obj->ioo_bufcnt, obj->ioo_id);
 320                                         GOTO(preprw_cleanup, rc = -ENOMEM);
 321                                 }
 322                         }
 323
 324                         tot_bytes += nb->len;
 325
 326                         atomic_inc(&obd->u.echo.eo_prep);
 327
 328                         r->offset = nb->offset;
 329                         r->len = nb->len;
 330                         LASSERT((r->offset & ~CFS_PAGE_MASK) + r->len <= CFS_PAGE_SIZE);
 331
 332                         CDEBUG(D_PAGE, "$$$$ get page %p @ "LPU64" for %d\n",
 333                                r->page, r->offset, r->len);
 334
 335                         if (cmd & OBD_BRW_READ)
 336                                 r->rc = r->len;
 337
 338                         if (debug_setup)
 339                                 echo_page_debug_setup(r->page, cmd, obj->ioo_id,
 340                                                       r->offset, r->len);
 341                 }
 342         }
 343         if (cmd & OBD_BRW_READ)
 344                 lprocfs_counter_add(obd->obd_stats, LPROC_ECHO_READ_BYTES,
 345                                     tot_bytes);
 346         else
 347                 lprocfs_counter_add(obd->obd_stats, LPROC_ECHO_WRITE_BYTES,
 348                                     tot_bytes);
 349
 350         CDEBUG(D_PAGE, "%d pages allocated after prep\n",
 351                atomic_read(&obd->u.echo.eo_prep));
 352
 353         RETURN(0);
 354
 355 preprw_cleanup:
 356         /* It is possible that we would rather handle errors by  allow
 357          * any already-set-up pages to complete, rather than tearing them
 358          * all down again.  I believe that this is what the in-kernel
 359          * prep/commit operations do.
 360          */
 361         CERROR("cleaning up %ld pages (%d obdos)\n", (long)(r - res), objcount);
 362         while (r-- > res) {
 363                 cfs_kunmap(r->page);
 364                 /* NB if this is a persistent page, __free_pages will just
 365                  * lose the extra ref gained above */
 366                 OBD_PAGE_FREE(r->page);
 367                 atomic_dec(&obd->u.echo.eo_prep);
 368         }
 369         memset(res, 0, sizeof(*res) * niocount);
 370
 371         return rc;
 372 }
 373
 374 int echo_commitrw(int cmd, struct obd_export *export, struct obdo *oa,
 375                   int objcount, struct obd_ioobj *obj, int niocount,
 376                   struct niobuf_local *res, struct obd_trans_info *oti, int rc)
 377 {
 378         struct obd_device *obd;
 379         struct niobuf_local *r = res;
 380         int i, vrc = 0;
 381         ENTRY;
 382
 383         obd = export->exp_obd;
 384         if (obd == NULL)
 385                 RETURN(-EINVAL);
 386
 387         if (rc)
 388                 GOTO(commitrw_cleanup, rc);
 389
 390         if ((cmd & OBD_BRW_RWMASK) == OBD_BRW_READ) {
 391                 CDEBUG(D_PAGE, "reading %d obdos with %d IOs\n",
 392                        objcount, niocount);
 393         } else {
 394                 CDEBUG(D_PAGE, "writing %d obdos with %d IOs\n",
 395                        objcount, niocount);
 396         }
 397
 398         if (niocount && !r) {
 399                 CERROR("NULL res niobuf with niocount %d\n", niocount);
 400                 RETURN(-EINVAL);
 401         }
 402
 403         LASSERT(oti == NULL || oti->oti_handle == (void *)DESC_PRIV);
 404
 405         for (i = 0; i < objcount; i++, obj++) {
 406                 int verify = (rc == 0 &&
 407                               obj->ioo_id != ECHO_PERSISTENT_OBJID &&
 408                               (oa->o_valid & OBD_MD_FLFLAGS) != 0 &&
 409                               (oa->o_flags & OBD_FL_DEBUG_CHECK) != 0);
 410                 int j;
 411
 412                 for (j = 0 ; j < obj->ioo_bufcnt ; j++, r++) {
 413                         cfs_page_t *page = r->page;
 414                         void *addr;
 415
 416                         if (page == NULL) {
 417                                 CERROR("null page objid "LPU64":%p, buf %d/%d\n",
 418                                        obj->ioo_id, page, j, obj->ioo_bufcnt);
 419                                 GOTO(commitrw_cleanup, rc = -EFAULT);
 420                         }
 421
 422                         addr = cfs_kmap(page);
 423
 424                         CDEBUG(D_PAGE, "$$$$ use page %p, addr %p@"LPU64"\n",
 425                                r->page, addr, r->offset);
 426
 427                         if (verify) {
 428                                 vrc = echo_page_debug_check(page, obj->ioo_id,
 429                                                             r->offset, r->len);
 430                                 /* check all the pages always */
 431                                 if (vrc != 0 && rc == 0)
 432                                         rc = vrc;
 433                         }
 434
 435                         cfs_kunmap(page);
 436                         /* NB see comment above regarding persistent pages */
 437                         OBD_PAGE_FREE(page);
 438                         atomic_dec(&obd->u.echo.eo_prep);
 439                 }
 440         }
 441         CDEBUG(D_PAGE, "%d pages remain after commit\n",
 442                atomic_read(&obd->u.echo.eo_prep));
 443         RETURN(rc);
 444
 445 commitrw_cleanup:
 446         CERROR("cleaning up %ld pages (%d obdos)\n",
 447                niocount - (long)(r - res) - 1, objcount);
 448         while (++r < res + niocount) {
 449                 cfs_page_t *page = r->page;
 450
 451                 /* NB see comment above regarding persistent pages */
 452                 OBD_PAGE_FREE(page);
 453                 atomic_dec(&obd->u.echo.eo_prep);
 454         }
 455         return rc;
 456 }
 457
 458 static int echo_setup(struct obd_device *obd, struct lustre_cfg *lcfg)
 459 {
 460         struct lprocfs_static_vars lvars;
 461         int                        rc;
 462         int                        lock_flags = 0;
 463         struct ldlm_res_id         res_id = {.name = {1}};
 464         ENTRY;
 465
 466         spin_lock_init(&obd->u.echo.eo_lock);
 467         obd->u.echo.eo_lastino = ECHO_INIT_OBJID;
 468
 469         obd->obd_namespace = ldlm_namespace_new("echo-tgt",
 470                                                 LDLM_NAMESPACE_SERVER,
 471                                                 LDLM_NAMESPACE_MODEST);
 472         if (obd->obd_namespace == NULL) {
 473                 LBUG();
 474                 RETURN(-ENOMEM);
 475         }
 476
 477         rc = ldlm_cli_enqueue_local(obd->obd_namespace, &res_id, LDLM_PLAIN,
 478                                     NULL, LCK_NL, &lock_flags, NULL,
 479                                     ldlm_completion_ast, NULL, NULL,
 480                                     0, NULL, &obd->u.echo.eo_nl_lock);
 481         LASSERT (rc == ELDLM_OK);
 482
 483         lprocfs_echo_init_vars(&lvars);
 484         if (lprocfs_obd_setup(obd, lvars.obd_vars) == 0 &&
 485             lprocfs_alloc_obd_stats(obd, LPROC_ECHO_LAST) == 0) {
 486                 lprocfs_counter_init(obd->obd_stats, LPROC_ECHO_READ_BYTES,
 487                                      LPROCFS_CNTR_AVGMINMAX,
 488                                      "read_bytes", "bytes");
 489                 lprocfs_counter_init(obd->obd_stats, LPROC_ECHO_WRITE_BYTES,
 490                                      LPROCFS_CNTR_AVGMINMAX,
 491                                      "write_bytes", "bytes");
 492         }
 493
 494         ptlrpc_init_client (LDLM_CB_REQUEST_PORTAL, LDLM_CB_REPLY_PORTAL,
 495                             "echo_ldlm_cb_client", &obd->obd_ldlm_client);
 496         RETURN(0);
 497 }
 498
 499 static int echo_cleanup(struct obd_device *obd)
 500 {
 501         int leaked;
 502         ENTRY;
 503
 504         lprocfs_obd_cleanup(obd);
 505         lprocfs_free_obd_stats(obd);
 506
 507         ldlm_lock_decref (&obd->u.echo.eo_nl_lock, LCK_NL);
 508
 509         /* XXX Bug 3413; wait for a bit to ensure the BL callback has
 510          * happened before calling ldlm_namespace_free() */
 511         set_current_state (TASK_UNINTERRUPTIBLE);
 512         cfs_schedule_timeout (CFS_TASK_UNINT, cfs_time_seconds(1));
 513
 514         ldlm_namespace_free(obd->obd_namespace, NULL, obd->obd_force);
 515
 516         leaked = atomic_read(&obd->u.echo.eo_prep);
 517         if (leaked != 0)
 518                 CERROR("%d prep/commitrw pages leaked\n", leaked);
 519
 520         RETURN(0);
 521 }
 522
 523 static struct obd_ops echo_obd_ops = {
 524         .o_owner           = THIS_MODULE,
 525         .o_connect         = echo_connect,
 526         .o_disconnect      = echo_disconnect,
 527         .o_destroy_export  = echo_destroy_export,
 528         .o_create          = echo_create,
 529         .o_destroy         = echo_destroy,
 530         .o_getattr         = echo_getattr,
 531         .o_setattr         = echo_setattr,
 532         .o_preprw          = echo_preprw,
 533         .o_commitrw        = echo_commitrw,
 534         .o_setup           = echo_setup,
 535         .o_cleanup         = echo_cleanup
 536 };
 537
 538 extern int echo_client_init(void);
 539 extern void echo_client_exit(void);
 540
 541 static void
 542 echo_persistent_pages_fini (void)
 543 {
 544         int     i;
 545
 546         for (i = 0; i < ECHO_PERSISTENT_PAGES; i++)
 547                 if (echo_persistent_pages[i] != NULL) {
 548                         OBD_PAGE_FREE(echo_persistent_pages[i]);
 549                         echo_persistent_pages[i] = NULL;
 550                 }
 551 }
 552
 553 static int
 554 echo_persistent_pages_init (void)
 555 {
 556         cfs_page_t *pg;
 557         int          i;
 558
 559         for (i = 0; i < ECHO_PERSISTENT_PAGES; i++) {
 560                 int gfp_mask = (i < ECHO_PERSISTENT_PAGES/2) ?
 561                         CFS_ALLOC_STD : CFS_ALLOC_HIGHUSER;
 562
 563                 OBD_PAGE_ALLOC(pg, gfp_mask);
 564                 if (pg == NULL) {
 565                         echo_persistent_pages_fini ();
 566                         return (-ENOMEM);
 567                 }
 568
 569                 memset (cfs_kmap (pg), 0, CFS_PAGE_SIZE);
 570                 cfs_kunmap (pg);
 571
 572                 echo_persistent_pages[i] = pg;
 573         }
 574
 575         return (0);
 576 }
 577
 578 static int __init obdecho_init(void)
 579 {
 580         struct lprocfs_static_vars lvars;
 581         int rc;
 582
 583         ENTRY;
 584         printk(KERN_INFO "Lustre: Echo OBD driver; info@clusterfs.com\n");
 585
 586         LASSERT(CFS_PAGE_SIZE % OBD_ECHO_BLOCK_SIZE == 0);
 587
 588         lprocfs_echo_init_vars(&lvars);
 589
 590         rc = echo_persistent_pages_init ();
 591         if (rc != 0)
 592                 goto failed_0;
 593
 594         rc = class_register_type(&echo_obd_ops, NULL, lvars.module_vars,
 595                                  LUSTRE_ECHO_NAME, NULL);
 596         if (rc != 0)
 597                 goto failed_1;
 598
 599         rc = echo_client_init();
 600         if (rc == 0)
 601                 RETURN (0);
 602
 603         class_unregister_type(LUSTRE_ECHO_NAME);
 604  failed_1:
 605         echo_persistent_pages_fini ();
 606  failed_0:
 607         RETURN(rc);
 608 }
 609
 610 static void /*__exit*/ obdecho_exit(void)
 611 {
 612         echo_client_exit();
 613         class_unregister_type(LUSTRE_ECHO_NAME);
 614         echo_persistent_pages_fini ();
 615 }
 616
 617 MODULE_AUTHOR("Cluster File Systems, Inc. <info@clusterfs.com>");
 618 MODULE_DESCRIPTION("Lustre Testing Echo OBD driver");
 619 MODULE_LICENSE("GPL");
 620
 621 cfs_module(obdecho, "1.0.0", obdecho_init, obdecho_exit);