lustre/obdecho/echo.c

   1 /*
   2  * GPL HEADER START
   3  *
   4  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
   5  *
   6  * This program is free software; you can redistribute it and/or modify
   7  * it under the terms of the GNU General Public License version 2 only,
   8  * as published by the Free Software Foundation.
   9  *
  10  * This program is distributed in the hope that it will be useful, but
  11  * WITHOUT ANY WARRANTY; without even the implied warranty of
  12  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  13  * General Public License version 2 for more details (a copy is included
  14  * in the LICENSE file that accompanied this code).
  15  *
  16  * You should have received a copy of the GNU General Public License
  17  * version 2 along with this program; If not, see
  18  * http://www.sun.com/software/products/lustre/docs/GPLv2.pdf
  19  *
  20  * Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
  21  * CA 95054 USA or visit www.sun.com if you need additional information or
  22  * have any questions.
  23  *
  24  * GPL HEADER END
  25  */
  26 /*
  27  * Copyright (c) 2002, 2010, Oracle and/or its affiliates. All rights reserved.
  28  * Use is subject to license terms.
  29  *
  30  * Copyright (c) 2010, 2011, Whamcloud, Inc.
  31  */
  32 /*
  33  * This file is part of Lustre, http://www.lustre.org/
  34  * Lustre is a trademark of Sun Microsystems, Inc.
  35  *
  36  * lustre/obdecho/echo.c
  37  *
  38  * Author: Peter Braam <braam@clusterfs.com>
  39  * Author: Andreas Dilger <adilger@clusterfs.com>
  40  */
  41
  42 #define DEBUG_SUBSYSTEM S_ECHO
  43
  44 #include <obd_support.h>
  45 #include <obd_class.h>
  46 #include <lustre_debug.h>
  47 #include <lustre_dlm.h>
  48 #include <lprocfs_status.h>
  49
  50 #include "echo_internal.h"
  51
  52 /* The echo objid needs to be below 2^32, because regular FID numbers are
  53  * limited to 2^32 objects in f_oid for the FID_SEQ_ECHO range. b=23335 */
  54 #define ECHO_INIT_OID        0x10000000ULL
  55 #define ECHO_HANDLE_MAGIC    0xabcd0123fedc9876ULL
  56
  57 #define ECHO_PERSISTENT_PAGES (ECHO_PERSISTENT_SIZE >> CFS_PAGE_SHIFT)
  58 static cfs_page_t *echo_persistent_pages[ECHO_PERSISTENT_PAGES];
  59
  60 enum {
  61         LPROC_ECHO_READ_BYTES = 1,
  62         LPROC_ECHO_WRITE_BYTES = 2,
  63         LPROC_ECHO_LAST = LPROC_ECHO_WRITE_BYTES +1
  64 };
  65
  66 static int echo_connect(const struct lu_env *env,
  67                         struct obd_export **exp, struct obd_device *obd,
  68                         struct obd_uuid *cluuid, struct obd_connect_data *data,
  69                         void *localdata)
  70 {
  71         struct lustre_handle conn = { 0 };
  72         int rc;
  73
  74         data->ocd_connect_flags &= ECHO_CONNECT_SUPPORTED;
  75         rc = class_connect(&conn, obd, cluuid);
  76         if (rc) {
  77                 CERROR("can't connect %d\n", rc);
  78                 return rc;
  79         }
  80         *exp = class_conn2export(&conn);
  81
  82         return 0;
  83 }
  84
  85 static int echo_disconnect(struct obd_export *exp)
  86 {
  87         LASSERT (exp != NULL);
  88
  89         return server_disconnect_export(exp);
  90 }
  91
  92 static int echo_init_export(struct obd_export *exp)
  93 {
  94         return ldlm_init_export(exp);
  95 }
  96
  97 static int echo_destroy_export(struct obd_export *exp)
  98 {
  99         ENTRY;
 100
 101         target_destroy_export(exp);
 102         ldlm_destroy_export(exp);
 103
 104         RETURN(0);
 105 }
 106
 107  static __u64 echo_next_id(struct obd_device *obddev)
 108 {
 109         obd_id id;
 110
 111         spin_lock(&obddev->u.echo.eo_lock);
 112         id = ++obddev->u.echo.eo_lastino;
 113         spin_unlock(&obddev->u.echo.eo_lock);
 114
 115         return id;
 116 }
 117
 118 static int echo_create(const struct lu_env *env, struct obd_export *exp,
 119                        struct obdo *oa, struct lov_stripe_md **ea,
 120                        struct obd_trans_info *oti)
 121 {
 122         struct obd_device *obd = class_exp2obd(exp);
 123
 124         if (!obd) {
 125                 CERROR("invalid client cookie "LPX64"\n",
 126                        exp->exp_handle.h_cookie);
 127                 return -EINVAL;
 128         }
 129
 130         if (!(oa->o_mode && S_IFMT)) {
 131                 CERROR("echo obd: no type!\n");
 132                 return -ENOENT;
 133         }
 134
 135         if (!(oa->o_valid & OBD_MD_FLTYPE)) {
 136                 CERROR("invalid o_valid "LPX64"\n", oa->o_valid);
 137                 return -EINVAL;
 138         }
 139
 140         oa->o_id = echo_next_id(obd);
 141         oa->o_valid = OBD_MD_FLID;
 142
 143         return 0;
 144 }
 145
 146 static int echo_destroy(const struct lu_env *env, struct obd_export *exp,
 147                         struct obdo *oa, struct lov_stripe_md *ea,
 148                         struct obd_trans_info *oti, struct obd_export *md_exp,
 149                         void *capa)
 150 {
 151         struct obd_device *obd = class_exp2obd(exp);
 152
 153         ENTRY;
 154         if (!obd) {
 155                 CERROR("invalid client cookie "LPX64"\n",
 156                        exp->exp_handle.h_cookie);
 157                 RETURN(-EINVAL);
 158         }
 159
 160         if (!(oa->o_valid & OBD_MD_FLID)) {
 161                 CERROR("obdo missing FLID valid flag: "LPX64"\n", oa->o_valid);
 162                 RETURN(-EINVAL);
 163         }
 164
 165         if (oa->o_id > obd->u.echo.eo_lastino || oa->o_id < ECHO_INIT_OID) {
 166                 CERROR("bad destroy objid: "LPX64"\n", oa->o_id);
 167                 RETURN(-EINVAL);
 168         }
 169
 170         RETURN(0);
 171 }
 172
 173 static int echo_getattr(const struct lu_env *env, struct obd_export *exp,
 174                         struct obd_info *oinfo)
 175 {
 176         struct obd_device *obd = class_exp2obd(exp);
 177         obd_id id = oinfo->oi_oa->o_id;
 178
 179         ENTRY;
 180         if (!obd) {
 181                 CERROR("invalid client cookie "LPX64"\n",
 182                        exp->exp_handle.h_cookie);
 183                 RETURN(-EINVAL);
 184         }
 185
 186         if (!(oinfo->oi_oa->o_valid & OBD_MD_FLID)) {
 187                 CERROR("obdo missing FLID valid flag: "LPX64"\n",
 188                        oinfo->oi_oa->o_valid);
 189                 RETURN(-EINVAL);
 190         }
 191
 192         obdo_cpy_md(oinfo->oi_oa, &obd->u.echo.eo_oa, oinfo->oi_oa->o_valid);
 193         oinfo->oi_oa->o_id = id;
 194
 195         RETURN(0);
 196 }
 197
 198 static int echo_setattr(const struct lu_env *env, struct obd_export *exp,
 199                         struct obd_info *oinfo, struct obd_trans_info *oti)
 200 {
 201         struct obd_device *obd = class_exp2obd(exp);
 202
 203         ENTRY;
 204         if (!obd) {
 205                 CERROR("invalid client cookie "LPX64"\n",
 206                        exp->exp_handle.h_cookie);
 207                 RETURN(-EINVAL);
 208         }
 209
 210         if (!(oinfo->oi_oa->o_valid & OBD_MD_FLID)) {
 211                 CERROR("obdo missing FLID valid flag: "LPX64"\n",
 212                        oinfo->oi_oa->o_valid);
 213                 RETURN(-EINVAL);
 214         }
 215
 216         memcpy(&obd->u.echo.eo_oa, oinfo->oi_oa, sizeof(*oinfo->oi_oa));
 217
 218         if (oinfo->oi_oa->o_id & 4) {
 219                 /* Save lock to force ACKed reply */
 220                 ldlm_lock_addref (&obd->u.echo.eo_nl_lock, LCK_NL);
 221                 oti->oti_ack_locks[0].mode = LCK_NL;
 222                 oti->oti_ack_locks[0].lock = obd->u.echo.eo_nl_lock;
 223         }
 224
 225         RETURN(0);
 226 }
 227
 228 static void
 229 echo_page_debug_setup(cfs_page_t *page, int rw, obd_id id,
 230                       __u64 offset, int len)
 231 {
 232         int   page_offset = offset & ~CFS_PAGE_MASK;
 233         char *addr        = ((char *)cfs_kmap(page)) + page_offset;
 234
 235         if (len % OBD_ECHO_BLOCK_SIZE != 0)
 236                 CERROR("Unexpected block size %d\n", len);
 237
 238         while (len > 0) {
 239                 if (rw & OBD_BRW_READ)
 240                         block_debug_setup(addr, OBD_ECHO_BLOCK_SIZE,
 241                                           offset, id);
 242                 else
 243                         block_debug_setup(addr, OBD_ECHO_BLOCK_SIZE,
 244                                           0xecc0ecc0ecc0ecc0ULL,
 245                                           0xecc0ecc0ecc0ecc0ULL);
 246
 247                 addr   += OBD_ECHO_BLOCK_SIZE;
 248                 offset += OBD_ECHO_BLOCK_SIZE;
 249                 len    -= OBD_ECHO_BLOCK_SIZE;
 250         }
 251
 252         cfs_kunmap(page);
 253 }
 254
 255 static int
 256 echo_page_debug_check(cfs_page_t *page, obd_id id,
 257                       __u64 offset, int len)
 258 {
 259         int   page_offset = offset & ~CFS_PAGE_MASK;
 260         char *addr        = ((char *)cfs_kmap(page)) + page_offset;
 261         int   rc          = 0;
 262         int   rc2;
 263
 264         if (len % OBD_ECHO_BLOCK_SIZE != 0)
 265                 CERROR("Unexpected block size %d\n", len);
 266
 267         while (len > 0) {
 268                 rc2 = block_debug_check("echo", addr, OBD_ECHO_BLOCK_SIZE,
 269                                         offset, id);
 270
 271                 if (rc2 != 0 && rc == 0)
 272                         rc = rc2;
 273
 274                 addr   += OBD_ECHO_BLOCK_SIZE;
 275                 offset += OBD_ECHO_BLOCK_SIZE;
 276                 len    -= OBD_ECHO_BLOCK_SIZE;
 277         }
 278
 279         cfs_kunmap(page);
 280
 281         return (rc);
 282 }
 283
 284 /* This allows us to verify that desc_private is passed unmolested */
 285 #define DESC_PRIV 0x10293847
 286
 287 static int echo_map_nb_to_lb(struct obdo *oa, struct obd_ioobj *obj,
 288                              struct niobuf_remote *nb, int *pages,
 289                              struct niobuf_local *lb, int cmd, int *left)
 290 {
 291         int gfp_mask = (obj->ioo_id & 1) ? CFS_ALLOC_HIGHUSER : CFS_ALLOC_STD;
 292         int ispersistent = obj->ioo_id == ECHO_PERSISTENT_OBJID;
 293         int debug_setup = (!ispersistent &&
 294                            (oa->o_valid & OBD_MD_FLFLAGS) != 0 &&
 295                            (oa->o_flags & OBD_FL_DEBUG_CHECK) != 0);
 296         struct niobuf_local *res = lb;
 297         obd_off offset = nb->offset;
 298         int len = nb->len;
 299
 300         while (len > 0) {
 301                 int plen = CFS_PAGE_SIZE - (offset & (CFS_PAGE_SIZE-1));
 302                 if (len < plen)
 303                         plen = len;
 304
 305                 /* check for local buf overflow */
 306                 if (*left == 0)
 307                         return -EINVAL;
 308
 309                 res->lnb_file_offset = offset;
 310                 res->len = plen;
 311                 LASSERT((res->lnb_file_offset & ~CFS_PAGE_MASK) + res->len <=
 312                         CFS_PAGE_SIZE);
 313
 314                 if (ispersistent &&
 315                     ((res->lnb_file_offset >> CFS_PAGE_SHIFT) <
 316                       ECHO_PERSISTENT_PAGES)) {
 317                         res->page =
 318                                 echo_persistent_pages[res->lnb_file_offset >>
 319                                                       CFS_PAGE_SHIFT];
 320                         /* Take extra ref so __free_pages() can be called OK */
 321                         cfs_get_page (res->page);
 322                 } else {
 323                         OBD_PAGE_ALLOC(res->page, gfp_mask);
 324                         if (res->page == NULL) {
 325                                 CERROR("can't get page for id " LPU64"\n",
 326                                        obj->ioo_id);
 327                                 return -ENOMEM;
 328                         }
 329                 }
 330
 331                 CDEBUG(D_PAGE, "$$$$ get page %p @ "LPU64" for %d\n",
 332                        res->page, res->lnb_file_offset, res->len);
 333
 334                 if (cmd & OBD_BRW_READ)
 335                         res->rc = res->len;
 336
 337                 if (debug_setup)
 338                         echo_page_debug_setup(res->page, cmd, obj->ioo_id,
 339                                               res->lnb_file_offset, res->len);
 340
 341                 offset += plen;
 342                 len -= plen;
 343                 res++;
 344
 345                 (*left)--;
 346                 (*pages)++;
 347         }
 348
 349         return 0;
 350 }
 351
 352 static int echo_finalize_lb(struct obdo *oa, struct obd_ioobj *obj,
 353                             struct niobuf_remote *rb, int *pgs,
 354                             struct niobuf_local *lb, int verify)
 355 {
 356         struct niobuf_local *res = lb;
 357         obd_off start  = rb->offset >> CFS_PAGE_SHIFT;
 358         obd_off end    = (rb->offset + rb->len + CFS_PAGE_SIZE - 1) >> CFS_PAGE_SHIFT;
 359         int     count  = (int)(end - start);
 360         int     rc     = 0;
 361         int     i;
 362
 363         for (i = 0; i < count; i++, (*pgs) ++, res++) {
 364                 cfs_page_t *page = res->page;
 365                 void       *addr;
 366
 367                 if (page == NULL) {
 368                         CERROR("null page objid "LPU64":%p, buf %d/%d\n",
 369                                obj->ioo_id, page, i, obj->ioo_bufcnt);
 370                         return -EFAULT;
 371                 }
 372
 373                 addr = cfs_kmap(page);
 374
 375                 CDEBUG(D_PAGE, "$$$$ use page %p, addr %p@"LPU64"\n",
 376                        res->page, addr, res->lnb_file_offset);
 377
 378                 if (verify) {
 379                         int vrc = echo_page_debug_check(page, obj->ioo_id,
 380                                                         res->lnb_file_offset,
 381                                                         res->len);
 382                         /* check all the pages always */
 383                         if (vrc != 0 && rc == 0)
 384                                 rc = vrc;
 385                 }
 386
 387                 cfs_kunmap(page);
 388                 /* NB see comment above regarding persistent pages */
 389                 OBD_PAGE_FREE(page);
 390         }
 391
 392         return rc;
 393 }
 394
 395 static int echo_preprw(const struct lu_env *env, int cmd,
 396                        struct obd_export *export, struct obdo *oa,
 397                        int objcount, struct obd_ioobj *obj,
 398                        struct niobuf_remote *nb, int *pages,
 399                        struct niobuf_local *res, struct obd_trans_info *oti,
 400                        struct lustre_capa *unused)
 401 {
 402         struct obd_device *obd;
 403         int tot_bytes = 0;
 404         int rc = 0;
 405         int i, left;
 406         ENTRY;
 407
 408         obd = export->exp_obd;
 409         if (obd == NULL)
 410                 RETURN(-EINVAL);
 411
 412         /* Temp fix to stop falling foul of osc_announce_cached() */
 413         oa->o_valid &= ~(OBD_MD_FLBLOCKS | OBD_MD_FLGRANT);
 414
 415         memset(res, 0, sizeof(*res) * *pages);
 416
 417         CDEBUG(D_PAGE, "%s %d obdos with %d IOs\n",
 418                cmd == OBD_BRW_READ ? "reading" : "writing", objcount, *pages);
 419
 420         if (oti)
 421                 oti->oti_handle = (void *)DESC_PRIV;
 422
 423         left = *pages;
 424         *pages = 0;
 425
 426         for (i = 0; i < objcount; i++, obj++) {
 427                 int j;
 428
 429                 for (j = 0 ; j < obj->ioo_bufcnt ; j++, nb++) {
 430
 431                         rc = echo_map_nb_to_lb(oa, obj, nb, pages,
 432                                                res + *pages, cmd, &left);
 433                         if (rc)
 434                                 GOTO(preprw_cleanup, rc);
 435
 436                         tot_bytes += nb->len;
 437                 }
 438         }
 439
 440         cfs_atomic_add(*pages, &obd->u.echo.eo_prep);
 441
 442         if (cmd & OBD_BRW_READ)
 443                 lprocfs_counter_add(obd->obd_stats, LPROC_ECHO_READ_BYTES,
 444                                     tot_bytes);
 445         else
 446                 lprocfs_counter_add(obd->obd_stats, LPROC_ECHO_WRITE_BYTES,
 447                                     tot_bytes);
 448
 449         CDEBUG(D_PAGE, "%d pages allocated after prep\n",
 450                cfs_atomic_read(&obd->u.echo.eo_prep));
 451
 452         RETURN(0);
 453
 454 preprw_cleanup:
 455         /* It is possible that we would rather handle errors by  allow
 456          * any already-set-up pages to complete, rather than tearing them
 457          * all down again.  I believe that this is what the in-kernel
 458          * prep/commit operations do.
 459          */
 460         CERROR("cleaning up %u pages (%d obdos)\n", *pages, objcount);
 461         for (i = 0; i < *pages; i++) {
 462                 cfs_kunmap(res[i].page);
 463                 /* NB if this is a persistent page, __free_pages will just
 464                  * lose the extra ref gained above */
 465                 OBD_PAGE_FREE(res[i].page);
 466                 res[i].page = NULL;
 467                 cfs_atomic_dec(&obd->u.echo.eo_prep);
 468         }
 469
 470         return rc;
 471 }
 472
 473 static int echo_commitrw(const struct lu_env *env, int cmd,
 474                          struct obd_export *export, struct obdo *oa,
 475                          int objcount, struct obd_ioobj *obj,
 476                          struct niobuf_remote *rb, int niocount,
 477                          struct niobuf_local *res, struct obd_trans_info *oti,
 478                          int rc)
 479 {
 480         struct obd_device *obd;
 481         int pgs = 0;
 482         int i;
 483         ENTRY;
 484
 485         obd = export->exp_obd;
 486         if (obd == NULL)
 487                 RETURN(-EINVAL);
 488
 489         if (rc)
 490                 GOTO(commitrw_cleanup, rc);
 491
 492         if ((cmd & OBD_BRW_RWMASK) == OBD_BRW_READ) {
 493                 CDEBUG(D_PAGE, "reading %d obdos with %d IOs\n",
 494                        objcount, niocount);
 495         } else {
 496                 CDEBUG(D_PAGE, "writing %d obdos with %d IOs\n",
 497                        objcount, niocount);
 498         }
 499
 500         if (niocount && res == NULL) {
 501                 CERROR("NULL res niobuf with niocount %d\n", niocount);
 502                 RETURN(-EINVAL);
 503         }
 504
 505         LASSERT(oti == NULL || oti->oti_handle == (void *)DESC_PRIV);
 506
 507         for (i = 0; i < objcount; i++, obj++) {
 508                 int verify = (rc == 0 &&
 509                               obj->ioo_id != ECHO_PERSISTENT_OBJID &&
 510                               (oa->o_valid & OBD_MD_FLFLAGS) != 0 &&
 511                               (oa->o_flags & OBD_FL_DEBUG_CHECK) != 0);
 512                 int j;
 513
 514                 for (j = 0 ; j < obj->ioo_bufcnt ; j++, rb++) {
 515                         int vrc = echo_finalize_lb(oa, obj, rb, &pgs, &res[pgs], verify);
 516
 517                         if (vrc == 0)
 518                                 continue;
 519
 520                         if (vrc == -EFAULT)
 521                                 GOTO(commitrw_cleanup, rc = vrc);
 522
 523                         if (rc == 0)
 524                                 rc = vrc;
 525                 }
 526
 527         }
 528
 529         cfs_atomic_sub(pgs, &obd->u.echo.eo_prep);
 530
 531         CDEBUG(D_PAGE, "%d pages remain after commit\n",
 532                cfs_atomic_read(&obd->u.echo.eo_prep));
 533         RETURN(rc);
 534
 535 commitrw_cleanup:
 536         cfs_atomic_sub(pgs, &obd->u.echo.eo_prep);
 537
 538         CERROR("cleaning up %d pages (%d obdos)\n",
 539                niocount - pgs - 1, objcount);
 540
 541         while (pgs < niocount) {
 542                 cfs_page_t *page = res[pgs++].page;
 543
 544                 if (page == NULL)
 545                         continue;
 546
 547                 /* NB see comment above regarding persistent pages */
 548                 OBD_PAGE_FREE(page);
 549                 cfs_atomic_dec(&obd->u.echo.eo_prep);
 550         }
 551         return rc;
 552 }
 553
 554 static int echo_setup(struct obd_device *obd, struct lustre_cfg *lcfg)
 555 {
 556         struct lprocfs_static_vars lvars;
 557         int                        rc;
 558         __u64                      lock_flags = 0;
 559         struct ldlm_res_id         res_id = {.name = {1}};
 560         char                       ns_name[48];
 561         ENTRY;
 562
 563         obd->u.echo.eo_obt.obt_magic = OBT_MAGIC;
 564         spin_lock_init(&obd->u.echo.eo_lock);
 565         obd->u.echo.eo_lastino = ECHO_INIT_OID;
 566
 567         sprintf(ns_name, "echotgt-%s", obd->obd_uuid.uuid);
 568         obd->obd_namespace = ldlm_namespace_new(obd, ns_name,
 569                                                 LDLM_NAMESPACE_SERVER,
 570                                                 LDLM_NAMESPACE_MODEST,
 571                                                 LDLM_NS_TYPE_OST);
 572         if (obd->obd_namespace == NULL) {
 573                 LBUG();
 574                 RETURN(-ENOMEM);
 575         }
 576
 577         rc = ldlm_cli_enqueue_local(obd->obd_namespace, &res_id, LDLM_PLAIN,
 578                                     NULL, LCK_NL, &lock_flags, NULL,
 579                                     ldlm_completion_ast, NULL, NULL, 0,
 580                                     LVB_T_NONE, NULL, &obd->u.echo.eo_nl_lock);
 581         LASSERT (rc == ELDLM_OK);
 582
 583         lprocfs_echo_init_vars(&lvars);
 584         if (lprocfs_obd_setup(obd, lvars.obd_vars) == 0 &&
 585             lprocfs_alloc_obd_stats(obd, LPROC_ECHO_LAST) == 0) {
 586                 lprocfs_counter_init(obd->obd_stats, LPROC_ECHO_READ_BYTES,
 587                                      LPROCFS_CNTR_AVGMINMAX,
 588                                      "read_bytes", "bytes");
 589                 lprocfs_counter_init(obd->obd_stats, LPROC_ECHO_WRITE_BYTES,
 590                                      LPROCFS_CNTR_AVGMINMAX,
 591                                      "write_bytes", "bytes");
 592         }
 593
 594         ptlrpc_init_client (LDLM_CB_REQUEST_PORTAL, LDLM_CB_REPLY_PORTAL,
 595                             "echo_ldlm_cb_client", &obd->obd_ldlm_client);
 596         RETURN(0);
 597 }
 598
 599 static int echo_cleanup(struct obd_device *obd)
 600 {
 601         int leaked;
 602         ENTRY;
 603
 604         lprocfs_obd_cleanup(obd);
 605         lprocfs_free_obd_stats(obd);
 606
 607         ldlm_lock_decref(&obd->u.echo.eo_nl_lock, LCK_NL);
 608
 609         /* XXX Bug 3413; wait for a bit to ensure the BL callback has
 610          * happened before calling ldlm_namespace_free() */
 611         cfs_schedule_timeout_and_set_state(CFS_TASK_UNINT, cfs_time_seconds(1));
 612
 613         ldlm_namespace_free(obd->obd_namespace, NULL, obd->obd_force);
 614         obd->obd_namespace = NULL;
 615
 616         leaked = cfs_atomic_read(&obd->u.echo.eo_prep);
 617         if (leaked != 0)
 618                 CERROR("%d prep/commitrw pages leaked\n", leaked);
 619
 620         RETURN(0);
 621 }
 622
 623 struct obd_ops echo_obd_ops = {
 624         .o_owner           = THIS_MODULE,
 625         .o_connect         = echo_connect,
 626         .o_disconnect      = echo_disconnect,
 627         .o_init_export     = echo_init_export,
 628         .o_destroy_export  = echo_destroy_export,
 629         .o_create          = echo_create,
 630         .o_destroy         = echo_destroy,
 631         .o_getattr         = echo_getattr,
 632         .o_setattr         = echo_setattr,
 633         .o_preprw          = echo_preprw,
 634         .o_commitrw        = echo_commitrw,
 635         .o_setup           = echo_setup,
 636         .o_cleanup         = echo_cleanup
 637 };
 638
 639 void echo_persistent_pages_fini(void)
 640 {
 641         int     i;
 642
 643         for (i = 0; i < ECHO_PERSISTENT_PAGES; i++)
 644                 if (echo_persistent_pages[i] != NULL) {
 645                         OBD_PAGE_FREE(echo_persistent_pages[i]);
 646                         echo_persistent_pages[i] = NULL;
 647                 }
 648 }
 649
 650 int echo_persistent_pages_init(void)
 651 {
 652         cfs_page_t *pg;
 653         int          i;
 654
 655         for (i = 0; i < ECHO_PERSISTENT_PAGES; i++) {
 656                 int gfp_mask = (i < ECHO_PERSISTENT_PAGES/2) ?
 657                         CFS_ALLOC_STD : CFS_ALLOC_HIGHUSER;
 658
 659                 OBD_PAGE_ALLOC(pg, gfp_mask);
 660                 if (pg == NULL) {
 661                         echo_persistent_pages_fini ();
 662                         return (-ENOMEM);
 663                 }
 664
 665                 memset (cfs_kmap (pg), 0, CFS_PAGE_SIZE);
 666                 cfs_kunmap (pg);
 667
 668                 echo_persistent_pages[i] = pg;
 669         }
 670
 671         return (0);
 672 }