lustre/obdecho/echo.c

   1 /* -*- mode: c; c-basic-offset: 8; indent-tabs-mode: nil; -*-
   2  * vim:expandtab:shiftwidth=8:tabstop=8:
   3  *
   4  * GPL HEADER START
   5  *
   6  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
   7  *
   8  * This program is free software; you can redistribute it and/or modify
   9  * it under the terms of the GNU General Public License version 2 only,
  10  * as published by the Free Software Foundation.
  11  *
  12  * This program is distributed in the hope that it will be useful, but
  13  * WITHOUT ANY WARRANTY; without even the implied warranty of
  14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  15  * General Public License version 2 for more details (a copy is included
  16  * in the LICENSE file that accompanied this code).
  17  *
  18  * You should have received a copy of the GNU General Public License
  19  * version 2 along with this program; If not, see
  20  * http://www.sun.com/software/products/lustre/docs/GPLv2.pdf
  21  *
  22  * Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
  23  * CA 95054 USA or visit www.sun.com if you need additional information or
  24  * have any questions.
  25  *
  26  * GPL HEADER END
  27  */
  28 /*
  29  * Copyright  2008 Sun Microsystems, Inc. All rights reserved
  30  * Use is subject to license terms.
  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 #ifndef EXPORT_SYMTAB
  43 # define EXPORT_SYMTAB
  44 #endif
  45
  46 #define DEBUG_SUBSYSTEM S_ECHO
  47
  48 #include <obd_support.h>
  49 #include <obd_class.h>
  50 #include <lustre_debug.h>
  51 #include <lustre_dlm.h>
  52 #include <lprocfs_status.h>
  53
  54 #include "echo_internal.h"
  55
  56 #define ECHO_INIT_OBJID      0x1000000000000000ULL
  57 #define ECHO_HANDLE_MAGIC    0xabcd0123fedc9876ULL
  58
  59 #define ECHO_PERSISTENT_PAGES (ECHO_PERSISTENT_SIZE >> CFS_PAGE_SHIFT)
  60 static cfs_page_t *echo_persistent_pages[ECHO_PERSISTENT_PAGES];
  61
  62 enum {
  63         LPROC_ECHO_READ_BYTES = 1,
  64         LPROC_ECHO_WRITE_BYTES = 2,
  65         LPROC_ECHO_LAST = LPROC_ECHO_WRITE_BYTES +1
  66 };
  67
  68 static int echo_connect(const struct lu_env *env,
  69                         struct obd_export **exp, struct obd_device *obd,
  70                         struct obd_uuid *cluuid, struct obd_connect_data *data,
  71                         void *localdata)
  72 {
  73         struct lustre_handle conn = { 0 };
  74         int rc;
  75
  76         data->ocd_connect_flags &= ECHO_CONNECT_SUPPORTED;
  77         rc = class_connect(&conn, obd, cluuid);
  78         if (rc) {
  79                 CERROR("can't connect %d\n", rc);
  80                 return rc;
  81         }
  82         *exp = class_conn2export(&conn);
  83
  84         return 0;
  85 }
  86
  87 static int echo_disconnect(struct obd_export *exp)
  88 {
  89         LASSERT (exp != NULL);
  90
  91         return server_disconnect_export(exp);
  92 }
  93
  94 static int echo_init_export(struct obd_export *exp)
  95 {
  96         return ldlm_init_export(exp);
  97 }
  98
  99 static int echo_destroy_export(struct obd_export *exp)
 100 {
 101         ENTRY;
 102
 103         target_destroy_export(exp);
 104         ldlm_destroy_export(exp);
 105
 106         RETURN(0);
 107 }
 108
 109  static __u64 echo_next_id(struct obd_device *obddev)
 110 {
 111         obd_id id;
 112
 113         cfs_spin_lock(&obddev->u.echo.eo_lock);
 114         id = ++obddev->u.echo.eo_lastino;
 115         cfs_spin_unlock(&obddev->u.echo.eo_lock);
 116
 117         return id;
 118 }
 119
 120 int echo_create(struct obd_export *exp, struct obdo *oa,
 121                 struct lov_stripe_md **ea, struct obd_trans_info *oti)
 122 {
 123         struct obd_device *obd = class_exp2obd(exp);
 124
 125         if (!obd) {
 126                 CERROR("invalid client cookie "LPX64"\n",
 127                        exp->exp_handle.h_cookie);
 128                 return -EINVAL;
 129         }
 130
 131         if (!(oa->o_mode && S_IFMT)) {
 132                 CERROR("echo obd: no type!\n");
 133                 return -ENOENT;
 134         }
 135
 136         if (!(oa->o_valid & OBD_MD_FLTYPE)) {
 137                 CERROR("invalid o_valid "LPX64"\n", oa->o_valid);
 138                 return -EINVAL;
 139         }
 140
 141         oa->o_id = echo_next_id(obd);
 142         oa->o_valid = OBD_MD_FLID;
 143
 144         return 0;
 145 }
 146
 147 int echo_destroy(struct obd_export *exp, struct obdo *oa,
 148                  struct lov_stripe_md *ea, struct obd_trans_info *oti,
 149                  struct obd_export *md_exp, 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_OBJID) {
 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(struct obd_export *exp, struct obd_info *oinfo)
 174 {
 175         struct obd_device *obd = class_exp2obd(exp);
 176         obd_id id = oinfo->oi_oa->o_id;
 177
 178         ENTRY;
 179         if (!obd) {
 180                 CERROR("invalid client cookie "LPX64"\n",
 181                        exp->exp_handle.h_cookie);
 182                 RETURN(-EINVAL);
 183         }
 184
 185         if (!(oinfo->oi_oa->o_valid & OBD_MD_FLID)) {
 186                 CERROR("obdo missing FLID valid flag: "LPX64"\n",
 187                        oinfo->oi_oa->o_valid);
 188                 RETURN(-EINVAL);
 189         }
 190
 191         obdo_cpy_md(oinfo->oi_oa, &obd->u.echo.eo_oa, oinfo->oi_oa->o_valid);
 192         oinfo->oi_oa->o_id = id;
 193
 194         RETURN(0);
 195 }
 196
 197 static int echo_setattr(struct obd_export *exp, struct obd_info *oinfo,
 198                         struct obd_trans_info *oti)
 199 {
 200         struct obd_device *obd = class_exp2obd(exp);
 201
 202         ENTRY;
 203         if (!obd) {
 204                 CERROR("invalid client cookie "LPX64"\n",
 205                        exp->exp_handle.h_cookie);
 206                 RETURN(-EINVAL);
 207         }
 208
 209         if (!(oinfo->oi_oa->o_valid & OBD_MD_FLID)) {
 210                 CERROR("obdo missing FLID valid flag: "LPX64"\n",
 211                        oinfo->oi_oa->o_valid);
 212                 RETURN(-EINVAL);
 213         }
 214
 215         memcpy(&obd->u.echo.eo_oa, oinfo->oi_oa, sizeof(*oinfo->oi_oa));
 216
 217         if (oinfo->oi_oa->o_id & 4) {
 218                 /* Save lock to force ACKed reply */
 219                 ldlm_lock_addref (&obd->u.echo.eo_nl_lock, LCK_NL);
 220                 oti->oti_ack_locks[0].mode = LCK_NL;
 221                 oti->oti_ack_locks[0].lock = obd->u.echo.eo_nl_lock;
 222         }
 223
 224         RETURN(0);
 225 }
 226
 227 static void
 228 echo_page_debug_setup(cfs_page_t *page, int rw, obd_id id,
 229                       __u64 offset, int len)
 230 {
 231         int   page_offset = offset & ~CFS_PAGE_MASK;
 232         char *addr        = ((char *)cfs_kmap(page)) + page_offset;
 233
 234         if (len % OBD_ECHO_BLOCK_SIZE != 0)
 235                 CERROR("Unexpected block size %d\n", len);
 236
 237         while (len > 0) {
 238                 if (rw & OBD_BRW_READ)
 239                         block_debug_setup(addr, OBD_ECHO_BLOCK_SIZE,
 240                                           offset, id);
 241                 else
 242                         block_debug_setup(addr, OBD_ECHO_BLOCK_SIZE,
 243                                           0xecc0ecc0ecc0ecc0ULL,
 244                                           0xecc0ecc0ecc0ecc0ULL);
 245
 246                 addr   += OBD_ECHO_BLOCK_SIZE;
 247                 offset += OBD_ECHO_BLOCK_SIZE;
 248                 len    -= OBD_ECHO_BLOCK_SIZE;
 249         }
 250
 251         cfs_kunmap(page);
 252 }
 253
 254 static int
 255 echo_page_debug_check(cfs_page_t *page, obd_id id,
 256                       __u64 offset, int len)
 257 {
 258         int   page_offset = offset & ~CFS_PAGE_MASK;
 259         char *addr        = ((char *)cfs_kmap(page)) + page_offset;
 260         int   rc          = 0;
 261         int   rc2;
 262
 263         if (len % OBD_ECHO_BLOCK_SIZE != 0)
 264                 CERROR("Unexpected block size %d\n", len);
 265
 266         while (len > 0) {
 267                 rc2 = block_debug_check("echo", addr, OBD_ECHO_BLOCK_SIZE,
 268                                         offset, id);
 269
 270                 if (rc2 != 0 && rc == 0)
 271                         rc = rc2;
 272
 273                 addr   += OBD_ECHO_BLOCK_SIZE;
 274                 offset += OBD_ECHO_BLOCK_SIZE;
 275                 len    -= OBD_ECHO_BLOCK_SIZE;
 276         }
 277
 278         cfs_kunmap(page);
 279
 280         return (rc);
 281 }
 282
 283 /* This allows us to verify that desc_private is passed unmolested */
 284 #define DESC_PRIV 0x10293847
 285
 286 static int echo_map_nb_to_lb(struct obdo *oa, struct obd_ioobj *obj,
 287                              struct niobuf_remote *nb, int *pages,
 288                              struct niobuf_local *lb, int cmd, int *left)
 289 {
 290         int gfp_mask = (obj->ioo_id & 1) ? CFS_ALLOC_HIGHUSER : CFS_ALLOC_STD;
 291         int ispersistent = obj->ioo_id == ECHO_PERSISTENT_OBJID;
 292         int debug_setup = (!ispersistent &&
 293                            (oa->o_valid & OBD_MD_FLFLAGS) != 0 &&
 294                            (oa->o_flags & OBD_FL_DEBUG_CHECK) != 0);
 295         struct niobuf_local *res = lb;
 296         obd_off offset = nb->offset;
 297         int len = nb->len;
 298
 299         while (len > 0) {
 300                 int plen = CFS_PAGE_SIZE - (offset & (CFS_PAGE_SIZE-1));
 301                 if (len < plen)
 302                         plen = len;
 303
 304                 /* check for local buf overflow */
 305                 if (*left == 0)
 306                         return -EINVAL;
 307
 308                 res->offset = offset;
 309                 res->len = plen;
 310                 LASSERT((res->offset & ~CFS_PAGE_MASK) + res->len <= CFS_PAGE_SIZE);
 311
 312
 313                 if (ispersistent &&
 314                     (res->offset >> CFS_PAGE_SHIFT) < ECHO_PERSISTENT_PAGES) {
 315                         res->page = echo_persistent_pages[res->offset >>
 316                                 CFS_PAGE_SHIFT];
 317                         /* Take extra ref so __free_pages() can be called OK */
 318                         cfs_get_page (res->page);
 319                 } else {
 320                         OBD_PAGE_ALLOC(res->page, gfp_mask);
 321                         if (res->page == NULL) {
 322                                 CERROR("can't get page for id " LPU64"\n",
 323                                        obj->ioo_id);
 324                                 return -ENOMEM;
 325                         }
 326                 }
 327
 328                 CDEBUG(D_PAGE, "$$$$ get page %p @ "LPU64" for %d\n",
 329                        res->page, res->offset, res->len);
 330
 331                 if (cmd & OBD_BRW_READ)
 332                         res->rc = res->len;
 333
 334                 if (debug_setup)
 335                         echo_page_debug_setup(res->page, cmd, obj->ioo_id,
 336                                               res->offset, res->len);
 337
 338                 offset += plen;
 339                 len -= plen;
 340                 res++;
 341
 342                 (*left)--;
 343                 (*pages)++;
 344         }
 345
 346         return 0;
 347 }
 348
 349 static int echo_finalize_lb(struct obdo *oa, struct obd_ioobj *obj,
 350                             struct niobuf_remote *rb, int *pgs,
 351                             struct niobuf_local *lb, int verify)
 352 {
 353         struct niobuf_local *res = lb;
 354         obd_off start  = rb->offset >> CFS_PAGE_SHIFT;
 355         obd_off end    = (rb->offset + rb->len + CFS_PAGE_SIZE - 1) >> CFS_PAGE_SHIFT;
 356         int     count  = (int)(end - start);
 357         int     rc     = 0;
 358         int     i;
 359
 360         for (i = 0; i < count; i++, (*pgs) ++, res++) {
 361                 cfs_page_t *page = res->page;
 362                 void       *addr;
 363
 364                 if (page == NULL) {
 365                         CERROR("null page objid "LPU64":%p, buf %d/%d\n",
 366                                obj->ioo_id, page, i, obj->ioo_bufcnt);
 367                         return -EFAULT;
 368                 }
 369
 370                 addr = cfs_kmap(page);
 371
 372                 CDEBUG(D_PAGE, "$$$$ use page %p, addr %p@"LPU64"\n",
 373                        res->page, addr, res->offset);
 374
 375                 if (verify) {
 376                         int vrc = echo_page_debug_check(page, obj->ioo_id,
 377                                                         res->offset, res->len);
 378                         /* check all the pages always */
 379                         if (vrc != 0 && rc == 0)
 380                                 rc = vrc;
 381                 }
 382
 383                 cfs_kunmap(page);
 384                 /* NB see comment above regarding persistent pages */
 385                 OBD_PAGE_FREE(page);
 386         }
 387
 388         return rc;
 389 }
 390
 391 int echo_preprw(int cmd, struct obd_export *export, struct obdo *oa,
 392                 int objcount, struct obd_ioobj *obj, struct niobuf_remote *nb,
 393                 int *pages, struct niobuf_local *res,
 394                 struct obd_trans_info *oti, struct lustre_capa *unused)
 395 {
 396         struct obd_device *obd;
 397         int tot_bytes = 0;
 398         int rc = 0;
 399         int i, left;
 400         ENTRY;
 401
 402         obd = export->exp_obd;
 403         if (obd == NULL)
 404                 RETURN(-EINVAL);
 405
 406         /* Temp fix to stop falling foul of osc_announce_cached() */
 407         oa->o_valid &= ~(OBD_MD_FLBLOCKS | OBD_MD_FLGRANT);
 408
 409         memset(res, 0, sizeof(*res) * *pages);
 410
 411         CDEBUG(D_PAGE, "%s %d obdos with %d IOs\n",
 412                cmd == OBD_BRW_READ ? "reading" : "writing", objcount, *pages);
 413
 414         if (oti)
 415                 oti->oti_handle = (void *)DESC_PRIV;
 416
 417         left = *pages;
 418         *pages = 0;
 419
 420         for (i = 0; i < objcount; i++, obj++) {
 421                 int j;
 422
 423                 for (j = 0 ; j < obj->ioo_bufcnt ; j++, nb++) {
 424
 425                         rc = echo_map_nb_to_lb(oa, obj, nb, pages,
 426                                                res + *pages, cmd, &left);
 427                         if (rc)
 428                                 GOTO(preprw_cleanup, rc);
 429
 430                         tot_bytes += nb->len;
 431                 }
 432         }
 433
 434         cfs_atomic_add(*pages, &obd->u.echo.eo_prep);
 435
 436         if (cmd & OBD_BRW_READ)
 437                 lprocfs_counter_add(obd->obd_stats, LPROC_ECHO_READ_BYTES,
 438                                     tot_bytes);
 439         else
 440                 lprocfs_counter_add(obd->obd_stats, LPROC_ECHO_WRITE_BYTES,
 441                                     tot_bytes);
 442
 443         CDEBUG(D_PAGE, "%d pages allocated after prep\n",
 444                cfs_atomic_read(&obd->u.echo.eo_prep));
 445
 446         RETURN(0);
 447
 448 preprw_cleanup:
 449         /* It is possible that we would rather handle errors by  allow
 450          * any already-set-up pages to complete, rather than tearing them
 451          * all down again.  I believe that this is what the in-kernel
 452          * prep/commit operations do.
 453          */
 454         CERROR("cleaning up %u pages (%d obdos)\n", *pages, objcount);
 455         for (i = 0; i < *pages; i++) {
 456                 cfs_kunmap(res[i].page);
 457                 /* NB if this is a persistent page, __free_pages will just
 458                  * lose the extra ref gained above */
 459                 OBD_PAGE_FREE(res[i].page);
 460                 res[i].page = NULL;
 461                 cfs_atomic_dec(&obd->u.echo.eo_prep);
 462         }
 463
 464         return rc;
 465 }
 466
 467 int echo_commitrw(int cmd, struct obd_export *export, struct obdo *oa,
 468                   int objcount, struct obd_ioobj *obj,
 469                   struct niobuf_remote *rb, int niocount,
 470                   struct niobuf_local *res, struct obd_trans_info *oti, int rc)
 471 {
 472         struct obd_device *obd;
 473         int pgs = 0;
 474         int i;
 475         ENTRY;
 476
 477         obd = export->exp_obd;
 478         if (obd == NULL)
 479                 RETURN(-EINVAL);
 480
 481         if (rc)
 482                 GOTO(commitrw_cleanup, rc);
 483
 484         if ((cmd & OBD_BRW_RWMASK) == OBD_BRW_READ) {
 485                 CDEBUG(D_PAGE, "reading %d obdos with %d IOs\n",
 486                        objcount, niocount);
 487         } else {
 488                 CDEBUG(D_PAGE, "writing %d obdos with %d IOs\n",
 489                        objcount, niocount);
 490         }
 491
 492         if (niocount && res == NULL) {
 493                 CERROR("NULL res niobuf with niocount %d\n", niocount);
 494                 RETURN(-EINVAL);
 495         }
 496
 497         LASSERT(oti == NULL || oti->oti_handle == (void *)DESC_PRIV);
 498
 499         for (i = 0; i < objcount; i++, obj++) {
 500                 int verify = (rc == 0 &&
 501                               obj->ioo_id != ECHO_PERSISTENT_OBJID &&
 502                               (oa->o_valid & OBD_MD_FLFLAGS) != 0 &&
 503                               (oa->o_flags & OBD_FL_DEBUG_CHECK) != 0);
 504                 int j;
 505
 506                 for (j = 0 ; j < obj->ioo_bufcnt ; j++, rb++) {
 507                         int vrc = echo_finalize_lb(oa, obj, rb, &pgs, &res[pgs], verify);
 508
 509                         if (vrc == 0)
 510                                 continue;
 511
 512                         if (vrc == -EFAULT)
 513                                 GOTO(commitrw_cleanup, rc = vrc);
 514
 515                         if (rc == 0)
 516                                 rc = vrc;
 517                 }
 518
 519         }
 520
 521         cfs_atomic_sub(pgs, &obd->u.echo.eo_prep);
 522
 523         CDEBUG(D_PAGE, "%d pages remain after commit\n",
 524                cfs_atomic_read(&obd->u.echo.eo_prep));
 525         RETURN(rc);
 526
 527 commitrw_cleanup:
 528         cfs_atomic_sub(pgs, &obd->u.echo.eo_prep);
 529
 530         CERROR("cleaning up %d pages (%d obdos)\n",
 531                niocount - pgs - 1, objcount);
 532
 533         while (pgs ++ < niocount) {
 534                 cfs_page_t *page = res[pgs].page;
 535
 536                 if (page == NULL)
 537                         continue;
 538
 539                 /* NB see comment above regarding persistent pages */
 540                 OBD_PAGE_FREE(page);
 541                 cfs_atomic_dec(&obd->u.echo.eo_prep);
 542         }
 543         return rc;
 544 }
 545
 546 static int echo_setup(struct obd_device *obd, struct lustre_cfg *lcfg)
 547 {
 548         struct lprocfs_static_vars lvars;
 549         int                        rc;
 550         int                        lock_flags = 0;
 551         struct ldlm_res_id         res_id = {.name = {1}};
 552         char                       ns_name[48];
 553         ENTRY;
 554
 555         cfs_spin_lock_init(&obd->u.echo.eo_lock);
 556         obd->u.echo.eo_lastino = ECHO_INIT_OBJID;
 557
 558         sprintf(ns_name, "echotgt-%s", obd->obd_uuid.uuid);
 559         obd->obd_namespace = ldlm_namespace_new(obd, ns_name,
 560                                                 LDLM_NAMESPACE_SERVER,
 561                                                 LDLM_NAMESPACE_MODEST);
 562         if (obd->obd_namespace == NULL) {
 563                 LBUG();
 564                 RETURN(-ENOMEM);
 565         }
 566
 567         rc = ldlm_cli_enqueue_local(obd->obd_namespace, &res_id, LDLM_PLAIN,
 568                                     NULL, LCK_NL, &lock_flags, NULL,
 569                                     ldlm_completion_ast, NULL, NULL, 0, NULL,
 570                                     &obd->u.echo.eo_nl_lock);
 571         LASSERT (rc == ELDLM_OK);
 572
 573         lprocfs_echo_init_vars(&lvars);
 574         if (lprocfs_obd_setup(obd, lvars.obd_vars) == 0 &&
 575             lprocfs_alloc_obd_stats(obd, LPROC_ECHO_LAST) == 0) {
 576                 lprocfs_counter_init(obd->obd_stats, LPROC_ECHO_READ_BYTES,
 577                                      LPROCFS_CNTR_AVGMINMAX,
 578                                      "read_bytes", "bytes");
 579                 lprocfs_counter_init(obd->obd_stats, LPROC_ECHO_WRITE_BYTES,
 580                                      LPROCFS_CNTR_AVGMINMAX,
 581                                      "write_bytes", "bytes");
 582         }
 583
 584         ptlrpc_init_client (LDLM_CB_REQUEST_PORTAL, LDLM_CB_REPLY_PORTAL,
 585                             "echo_ldlm_cb_client", &obd->obd_ldlm_client);
 586         RETURN(0);
 587 }
 588
 589 static int echo_cleanup(struct obd_device *obd)
 590 {
 591         int leaked;
 592         ENTRY;
 593
 594         lprocfs_obd_cleanup(obd);
 595         lprocfs_free_obd_stats(obd);
 596
 597         ldlm_lock_decref(&obd->u.echo.eo_nl_lock, LCK_NL);
 598
 599         /* XXX Bug 3413; wait for a bit to ensure the BL callback has
 600          * happened before calling ldlm_namespace_free() */
 601         cfs_schedule_timeout_and_set_state(CFS_TASK_UNINT, cfs_time_seconds(1));
 602
 603         ldlm_namespace_free(obd->obd_namespace, NULL, obd->obd_force);
 604         obd->obd_namespace = NULL;
 605
 606         leaked = cfs_atomic_read(&obd->u.echo.eo_prep);
 607         if (leaked != 0)
 608                 CERROR("%d prep/commitrw pages leaked\n", leaked);
 609
 610         RETURN(0);
 611 }
 612
 613 static struct obd_ops echo_obd_ops = {
 614         .o_owner           = THIS_MODULE,
 615         .o_connect         = echo_connect,
 616         .o_disconnect      = echo_disconnect,
 617         .o_init_export     = echo_init_export,
 618         .o_destroy_export  = echo_destroy_export,
 619         .o_create          = echo_create,
 620         .o_destroy         = echo_destroy,
 621         .o_getattr         = echo_getattr,
 622         .o_setattr         = echo_setattr,
 623         .o_preprw          = echo_preprw,
 624         .o_commitrw        = echo_commitrw,
 625         .o_setup           = echo_setup,
 626         .o_cleanup         = echo_cleanup
 627 };
 628
 629 extern int echo_client_init(void);
 630 extern void echo_client_exit(void);
 631
 632 static void
 633 echo_persistent_pages_fini (void)
 634 {
 635         int     i;
 636
 637         for (i = 0; i < ECHO_PERSISTENT_PAGES; i++)
 638                 if (echo_persistent_pages[i] != NULL) {
 639                         OBD_PAGE_FREE(echo_persistent_pages[i]);
 640                         echo_persistent_pages[i] = NULL;
 641                 }
 642 }
 643
 644 static int
 645 echo_persistent_pages_init (void)
 646 {
 647         cfs_page_t *pg;
 648         int          i;
 649
 650         for (i = 0; i < ECHO_PERSISTENT_PAGES; i++) {
 651                 int gfp_mask = (i < ECHO_PERSISTENT_PAGES/2) ?
 652                         CFS_ALLOC_STD : CFS_ALLOC_HIGHUSER;
 653
 654                 OBD_PAGE_ALLOC(pg, gfp_mask);
 655                 if (pg == NULL) {
 656                         echo_persistent_pages_fini ();
 657                         return (-ENOMEM);
 658                 }
 659
 660                 memset (cfs_kmap (pg), 0, CFS_PAGE_SIZE);
 661                 cfs_kunmap (pg);
 662
 663                 echo_persistent_pages[i] = pg;
 664         }
 665
 666         return (0);
 667 }
 668
 669 static int __init obdecho_init(void)
 670 {
 671         struct lprocfs_static_vars lvars;
 672         int rc;
 673
 674         ENTRY;
 675         LCONSOLE_INFO("Echo OBD driver; http://www.lustre.org/\n");
 676
 677         LASSERT(CFS_PAGE_SIZE % OBD_ECHO_BLOCK_SIZE == 0);
 678
 679         lprocfs_echo_init_vars(&lvars);
 680
 681         rc = echo_persistent_pages_init ();
 682         if (rc != 0)
 683                 goto failed_0;
 684
 685         rc = class_register_type(&echo_obd_ops, NULL, lvars.module_vars,
 686                                  LUSTRE_ECHO_NAME, NULL);
 687         if (rc != 0)
 688                 goto failed_1;
 689
 690         rc = echo_client_init();
 691         if (rc == 0)
 692                 RETURN (0);
 693
 694         class_unregister_type(LUSTRE_ECHO_NAME);
 695  failed_1:
 696         echo_persistent_pages_fini ();
 697  failed_0:
 698         RETURN(rc);
 699 }
 700
 701 static void /*__exit*/ obdecho_exit(void)
 702 {
 703         echo_client_exit();
 704         class_unregister_type(LUSTRE_ECHO_NAME);
 705         echo_persistent_pages_fini ();
 706 }
 707
 708 MODULE_AUTHOR("Sun Microsystems, Inc. <http://www.lustre.org/>");
 709 MODULE_DESCRIPTION("Lustre Testing Echo OBD driver");
 710 MODULE_LICENSE("GPL");
 711
 712 cfs_module(obdecho, "1.0.0", obdecho_init, obdecho_exit);