lustre/lov/lov_object.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  * Implementation of cl_object for LOV layer.
  37  *
  38  *   Author: Nikita Danilov <nikita.danilov@sun.com>
  39  */
  40
  41 #define DEBUG_SUBSYSTEM S_LOV
  42
  43 #include "lov_cl_internal.h"
  44
  45 /** \addtogroup lov
  46  *  @{
  47  */
  48
  49 /*****************************************************************************
  50  *
  51  * Layout operations.
  52  *
  53  */
  54
  55 struct lov_layout_operations {
  56         int (*llo_init)(const struct lu_env *env, struct lov_device *dev,
  57                         struct lov_object *lov,
  58                         const struct cl_object_conf *conf,
  59                         union lov_layout_state *state);
  60         void (*llo_delete)(const struct lu_env *env, struct lov_object *lov,
  61                            union lov_layout_state *state);
  62         void (*llo_fini)(const struct lu_env *env, struct lov_object *lov,
  63                          union lov_layout_state *state);
  64         void (*llo_install)(const struct lu_env *env, struct lov_object *lov,
  65                             union lov_layout_state *state);
  66         int  (*llo_print)(const struct lu_env *env, void *cookie,
  67                           lu_printer_t p, const struct lu_object *o);
  68         struct cl_page *(*llo_page_init)(const struct lu_env *env,
  69                                          struct cl_object *obj,
  70                                          struct cl_page *page,
  71                                          cfs_page_t *vmpage);
  72         int  (*llo_lock_init)(const struct lu_env *env,
  73                               struct cl_object *obj, struct cl_lock *lock,
  74                               const struct cl_io *io);
  75         int  (*llo_io_init)(const struct lu_env *env,
  76                             struct cl_object *obj, struct cl_io *io);
  77         int  (*llo_getattr)(const struct lu_env *env, struct cl_object *obj,
  78                             struct cl_attr *attr);
  79 };
  80
  81 /*****************************************************************************
  82  *
  83  * Lov object layout operations.
  84  *
  85  */
  86
  87 static void lov_install_empty(const struct lu_env *env,
  88                               struct lov_object *lov,
  89                               union  lov_layout_state *state)
  90 {
  91         /*
  92          * File without objects.
  93          */
  94 }
  95
  96 static int lov_init_empty(const struct lu_env *env,
  97                           struct lov_device *dev, struct lov_object *lov,
  98                           const struct cl_object_conf *conf,
  99                           union  lov_layout_state *state)
 100 {
 101         return 0;
 102 }
 103
 104 static void lov_install_raid0(const struct lu_env *env,
 105                               struct lov_object *lov,
 106                               union  lov_layout_state *state)
 107 {
 108         lov->u = *state;
 109 }
 110
 111 static void oinfo_get_fid(const struct lov_oinfo *oinfo, struct lu_fid *fid)
 112 {
 113         __u64 idx = oinfo->loi_id;
 114
 115         /* See idif definition in wiki:CMD3_interoperability_architecture */
 116
 117         LASSERT(oinfo->loi_gr < 1ULL << 16);
 118         LASSERT(oinfo->loi_id < 1ULL << 49);
 119         ENTRY;
 120
 121         /*
 122          * Now that the fid of stripe is not unique now, ost_idx have to
 123          * be used to make it unique. This is ok because the stripe fids
 124          * are just used in client side(to locate the objects). -jay
 125          */
 126         fid->f_seq = ((__u64)oinfo->loi_ost_idx) << 32 |
 127                      oinfo->loi_gr << 16 | idx >> 32;
 128         fid->f_oid = idx; /* truncated to 32 bits by assignment */
 129         fid->f_ver = 0;
 130         EXIT;
 131 }
 132
 133 static struct cl_object *lov_sub_find(const struct lu_env *env,
 134                                       struct cl_device *dev,
 135                                       const struct lu_fid *fid,
 136                                       const struct cl_object_conf *conf)
 137 {
 138         struct lu_object *o;
 139
 140         ENTRY;
 141         o = lu_object_find_at(env, cl2lu_dev(dev), fid, &conf->coc_lu);
 142         LASSERT(ergo(!IS_ERR(o), o->lo_dev->ld_type == &lovsub_device_type));
 143         RETURN(lu2cl(o));
 144 }
 145
 146 static int lov_init_sub(const struct lu_env *env, struct lov_object *lov,
 147                         struct cl_object *stripe,
 148                         struct lov_layout_raid0 *r0, int idx)
 149 {
 150         struct cl_object_header *hdr;
 151         struct cl_object_header *subhdr;
 152         struct cl_object_header *parent;
 153         struct lov_oinfo        *oinfo;
 154         int result;
 155
 156         hdr    = cl_object_header(lov2cl(lov));
 157         subhdr = cl_object_header(stripe);
 158         parent = subhdr->coh_parent;
 159
 160         oinfo = r0->lo_lsm->lsm_oinfo[idx];
 161         CDEBUG(D_INODE, DFID"@%p[%d] -> "DFID"@%p: id: "LPU64" gr: "LPU64
 162                " idx: %d gen: %d\n",
 163                PFID(&subhdr->coh_lu.loh_fid), subhdr, idx,
 164                PFID(&hdr->coh_lu.loh_fid), hdr,
 165                oinfo->loi_id, oinfo->loi_gr,
 166                oinfo->loi_ost_idx, oinfo->loi_ost_gen);
 167
 168         if (parent == NULL) {
 169                 subhdr->coh_parent = hdr;
 170                 subhdr->coh_nesting = hdr->coh_nesting + 1;
 171                 lu_object_ref_add(&stripe->co_lu, "lov-parent", lov);
 172                 r0->lo_sub[idx] = cl2lovsub(stripe);
 173                 r0->lo_sub[idx]->lso_super = lov;
 174                 r0->lo_sub[idx]->lso_index = idx;
 175                 result = 0;
 176         } else {
 177                 CERROR("Stripe is already owned by other file (%i).\n", idx);
 178                 LU_OBJECT_DEBUG(D_ERROR, env, &stripe->co_lu, "\n");
 179                 LU_OBJECT_DEBUG(D_ERROR, env, lu_object_top(&parent->coh_lu),
 180                                 "old\n");
 181                 LU_OBJECT_HEADER(D_ERROR, env, lov2lu(lov), "new\n");
 182                 cl_object_put(env, stripe);
 183                 result = -EIO;
 184         }
 185         return result;
 186 }
 187
 188 static int lov_init_raid0(const struct lu_env *env,
 189                           struct lov_device *dev, struct lov_object *lov,
 190                           const struct cl_object_conf *conf,
 191                           union  lov_layout_state *state)
 192 {
 193         int result;
 194         int i;
 195
 196         struct cl_object        *stripe;
 197         struct lov_thread_info  *lti     = lov_env_info(env);
 198         struct cl_object_conf   *subconf = &lti->lti_stripe_conf;
 199         struct lov_stripe_md    *lsm     = conf->u.coc_md->lsm;
 200         struct lu_fid           *ofid    = &lti->lti_fid;
 201         struct lov_layout_raid0 *r0      = &state->raid0;
 202
 203         ENTRY;
 204         r0->lo_nr  = conf->u.coc_md->lsm->lsm_stripe_count;
 205         r0->lo_lsm = conf->u.coc_md->lsm;
 206         LASSERT(r0->lo_nr <= lov_targets_nr(dev));
 207
 208         OBD_ALLOC(r0->lo_sub, r0->lo_nr * sizeof r0->lo_sub[0]);
 209         if (r0->lo_sub != NULL) {
 210                 result = 0;
 211                 subconf->coc_inode = conf->coc_inode;
 212                 cfs_spin_lock_init(&r0->lo_sub_lock);
 213                 /*
 214                  * Create stripe cl_objects.
 215                  */
 216                 for (i = 0; i < r0->lo_nr && result == 0; ++i) {
 217                         struct cl_device *subdev;
 218                         struct lov_oinfo *oinfo = lsm->lsm_oinfo[i];
 219                         int ost_idx = oinfo->loi_ost_idx;
 220
 221                         oinfo_get_fid(oinfo, ofid);
 222                         subdev = lovsub2cl_dev(dev->ld_target[ost_idx]);
 223                         subconf->u.coc_oinfo = oinfo;
 224                         LASSERTF(subdev != NULL, "not init ost %d\n", ost_idx);
 225                         stripe = lov_sub_find(env, subdev, ofid, subconf);
 226                         if (!IS_ERR(stripe))
 227                                 result = lov_init_sub(env, lov, stripe, r0, i);
 228                         else
 229                                 result = PTR_ERR(stripe);
 230                 }
 231         } else
 232                 result = -ENOMEM;
 233         RETURN(result);
 234 }
 235
 236 static void lov_delete_empty(const struct lu_env *env, struct lov_object *lov,
 237                              union lov_layout_state *state)
 238 {
 239         LASSERT(lov->lo_type == LLT_EMPTY);
 240 }
 241
 242 static void lov_subobject_kill(const struct lu_env *env, struct lov_object *lov,
 243                                struct lovsub_object *los, int idx)
 244 {
 245         struct cl_object        *sub;
 246         struct lov_layout_raid0 *r0;
 247         struct lu_site          *site;
 248         cfs_waitlink_t          *waiter;
 249
 250         r0  = &lov->u.raid0;
 251         LASSERT(r0->lo_sub[idx] == los);
 252
 253         sub  = lovsub2cl(los);
 254         site = sub->co_lu.lo_dev->ld_site;
 255
 256         cl_object_kill(env, sub);
 257         /* release a reference to the sub-object and ... */
 258         lu_object_ref_del(&sub->co_lu, "lov-parent", lov);
 259         cl_object_put(env, sub);
 260
 261         /* ... wait until it is actually destroyed---sub-object clears its
 262          * ->lo_sub[] slot in lovsub_object_fini() */
 263         if (r0->lo_sub[idx] == los) {
 264                 waiter = &lov_env_info(env)->lti_waiter;
 265                 cfs_waitlink_init(waiter);
 266                 cfs_waitq_add(&site->ls_marche_funebre, waiter);
 267                 cfs_set_current_state(CFS_TASK_UNINT);
 268                 while (1) {
 269                         /* this wait-queue is signaled at the end of
 270                          * lu_object_free(). */
 271                         cfs_set_current_state(CFS_TASK_UNINT);
 272                         cfs_spin_lock(&r0->lo_sub_lock);
 273                         if (r0->lo_sub[idx] == los) {
 274                                 cfs_spin_unlock(&r0->lo_sub_lock);
 275                                 cfs_waitq_wait(waiter, CFS_TASK_UNINT);
 276                         } else {
 277                                 cfs_spin_unlock(&r0->lo_sub_lock);
 278                                 cfs_set_current_state(CFS_TASK_RUNNING);
 279                                 break;
 280                         }
 281                 }
 282                 cfs_waitq_del(&site->ls_marche_funebre, waiter);
 283         }
 284         LASSERT(r0->lo_sub[idx] == NULL);
 285 }
 286
 287 static void lov_delete_raid0(const struct lu_env *env, struct lov_object *lov,
 288                              union lov_layout_state *state)
 289 {
 290         struct lov_layout_raid0 *r0 = &state->raid0;
 291         int                      i;
 292
 293         ENTRY;
 294         if (r0->lo_sub != NULL) {
 295                 for (i = 0; i < r0->lo_nr; ++i) {
 296                         struct lovsub_object *los = r0->lo_sub[i];
 297
 298                         if (los != NULL)
 299                                 /*
 300                                  * If top-level object is to be evicted from
 301                                  * the cache, so are its sub-objects.
 302                                  */
 303                                 lov_subobject_kill(env, lov, los, i);
 304                 }
 305         }
 306         EXIT;
 307 }
 308
 309 static void lov_fini_empty(const struct lu_env *env, struct lov_object *lov,
 310                            union lov_layout_state *state)
 311 {
 312         LASSERT(lov->lo_type == LLT_EMPTY);
 313 }
 314
 315 static void lov_fini_raid0(const struct lu_env *env, struct lov_object *lov,
 316                            union lov_layout_state *state)
 317 {
 318         struct lov_layout_raid0 *r0 = &state->raid0;
 319
 320         ENTRY;
 321         if (r0->lo_sub != NULL) {
 322                 OBD_FREE(r0->lo_sub, r0->lo_nr * sizeof r0->lo_sub[0]);
 323                 r0->lo_sub = NULL;
 324         }
 325         EXIT;
 326 }
 327
 328 static int lov_print_empty(const struct lu_env *env, void *cookie,
 329                            lu_printer_t p, const struct lu_object *o)
 330 {
 331         (*p)(env, cookie, "empty\n");
 332         return 0;
 333 }
 334
 335 static int lov_print_raid0(const struct lu_env *env, void *cookie,
 336                            lu_printer_t p, const struct lu_object *o)
 337 {
 338         struct lov_object       *lov = lu2lov(o);
 339         struct lov_layout_raid0 *r0  = lov_r0(lov);
 340         int i;
 341
 342         (*p)(env, cookie, "stripes: %d:\n", r0->lo_nr);
 343         for (i = 0; i < r0->lo_nr; ++i) {
 344                 struct lu_object *sub;
 345
 346                 if (r0->lo_sub[i] != NULL) {
 347                         sub = lovsub2lu(r0->lo_sub[i]);
 348                         lu_object_print(env, cookie, p, sub);
 349                 } else
 350                         (*p)(env, cookie, "sub %d absent\n", i);
 351         }
 352         return 0;
 353 }
 354
 355 /**
 356  * Implements cl_object_operations::coo_attr_get() method for an object
 357  * without stripes (LLT_EMPTY layout type).
 358  *
 359  * The only attributes this layer is authoritative in this case is
 360  * cl_attr::cat_blocks---it's 0.
 361  */
 362 static int lov_attr_get_empty(const struct lu_env *env, struct cl_object *obj,
 363                               struct cl_attr *attr)
 364 {
 365         attr->cat_blocks = 0;
 366         return 0;
 367 }
 368
 369 static int lov_attr_get_raid0(const struct lu_env *env, struct cl_object *obj,
 370                               struct cl_attr *attr)
 371 {
 372         struct lov_object       *lov = cl2lov(obj);
 373         struct lov_layout_raid0 *r0 = lov_r0(lov);
 374         struct lov_stripe_md    *lsm = lov->u.raid0.lo_lsm;
 375         struct ost_lvb          *lvb = &lov_env_info(env)->lti_lvb;
 376         __u64                    kms;
 377         int                      result = 0;
 378
 379         ENTRY;
 380         if (!r0->lo_attr_valid) {
 381                 /*
 382                  * Fill LVB with attributes already initialized by the upper
 383                  * layer.
 384                  */
 385                 cl_attr2lvb(lvb, attr);
 386                 kms = attr->cat_kms;
 387
 388                 /*
 389                  * XXX that should be replaced with a loop over sub-objects,
 390                  * doing cl_object_attr_get() on them. But for now, let's
 391                  * reuse old lov code.
 392                  */
 393
 394                 /*
 395                  * XXX take lsm spin-lock to keep lov_merge_lvb_kms()
 396                  * happy. It's not needed, because new code uses
 397                  * ->coh_attr_guard spin-lock to protect consistency of
 398                  * sub-object attributes.
 399                  */
 400                 lov_stripe_lock(lsm);
 401                 result = lov_merge_lvb_kms(lsm, lvb, &kms);
 402                 lov_stripe_unlock(lsm);
 403                 if (result == 0) {
 404                         cl_lvb2attr(attr, lvb);
 405                         attr->cat_kms = kms;
 406                         r0->lo_attr_valid = 1;
 407                         r0->lo_attr = *attr;
 408                 }
 409         } else
 410                 *attr = r0->lo_attr;
 411         RETURN(result);
 412 }
 413
 414 const static struct lov_layout_operations lov_dispatch[] = {
 415         [LLT_EMPTY] = {
 416                 .llo_init      = lov_init_empty,
 417                 .llo_delete    = lov_delete_empty,
 418                 .llo_fini      = lov_fini_empty,
 419                 .llo_install   = lov_install_empty,
 420                 .llo_print     = lov_print_empty,
 421                 .llo_page_init = lov_page_init_empty,
 422                 .llo_lock_init = NULL,
 423                 .llo_io_init   = lov_io_init_empty,
 424                 .llo_getattr   = lov_attr_get_empty
 425         },
 426         [LLT_RAID0] = {
 427                 .llo_init      = lov_init_raid0,
 428                 .llo_delete    = lov_delete_raid0,
 429                 .llo_fini      = lov_fini_raid0,
 430                 .llo_install   = lov_install_raid0,
 431                 .llo_print     = lov_print_raid0,
 432                 .llo_page_init = lov_page_init_raid0,
 433                 .llo_lock_init = lov_lock_init_raid0,
 434                 .llo_io_init   = lov_io_init_raid0,
 435                 .llo_getattr   = lov_attr_get_raid0
 436         }
 437 };
 438
 439
 440 /**
 441  * Performs a double-dispatch based on the layout type of an object.
 442  */
 443 #define LOV_2DISPATCH_NOLOCK(obj, op, ...)                              \
 444 ({                                                                      \
 445         struct lov_object                      *__obj = (obj);          \
 446         enum lov_layout_type                    __llt;                  \
 447                                                                         \
 448         __llt = __obj->lo_type;                                         \
 449         LASSERT(0 <= __llt && __llt < ARRAY_SIZE(lov_dispatch));        \
 450         lov_dispatch[__llt].op(__VA_ARGS__);                            \
 451 })
 452
 453 #define LOV_2DISPATCH_MAYLOCK(obj, op, lock, ...)                       \
 454 ({                                                                      \
 455         struct lov_object                      *__obj = (obj);          \
 456         int                                     __lock = !!(lock);      \
 457         typeof(lov_dispatch[0].op(__VA_ARGS__)) __result;               \
 458                                                                         \
 459         __lock &= __obj->lo_owner != cfs_current();                     \
 460         if (__lock)                                                     \
 461                 cfs_down_read(&__obj->lo_type_guard);                   \
 462         __result = LOV_2DISPATCH_NOLOCK(obj, op, __VA_ARGS__);          \
 463         if (__lock)                                                     \
 464                 cfs_up_read(&__obj->lo_type_guard);                     \
 465         __result;                                                       \
 466 })
 467
 468 /**
 469  * Performs a locked double-dispatch based on the layout type of an object.
 470  */
 471 #define LOV_2DISPATCH(obj, op, ...)                     \
 472         LOV_2DISPATCH_MAYLOCK(obj, op, 1, __VA_ARGS__)
 473
 474 #define LOV_2DISPATCH_VOID(obj, op, ...)                                \
 475 do {                                                                    \
 476         struct lov_object                      *__obj = (obj);          \
 477         enum lov_layout_type                    __llt;                  \
 478                                                                         \
 479         if (__obj->lo_owner != cfs_current())                           \
 480                 cfs_down_read(&__obj->lo_type_guard);                   \
 481         __llt = __obj->lo_type;                                         \
 482         LASSERT(0 <= __llt && __llt < ARRAY_SIZE(lov_dispatch));        \
 483         lov_dispatch[__llt].op(__VA_ARGS__);                            \
 484         if (__obj->lo_owner != cfs_current())                           \
 485                 cfs_up_read(&__obj->lo_type_guard);                     \
 486 } while (0)
 487
 488 static int lov_layout_change(const struct lu_env *env,
 489                              struct lov_object *obj, enum lov_layout_type llt,
 490                              const struct cl_object_conf *conf)
 491 {
 492         int result;
 493         union lov_layout_state       *state = &lov_env_info(env)->lti_state;
 494         const struct lov_layout_operations *old_ops;
 495         const struct lov_layout_operations *new_ops;
 496
 497         LASSERT(0 <= obj->lo_type && obj->lo_type < ARRAY_SIZE(lov_dispatch));
 498         LASSERT(0 <= llt && llt < ARRAY_SIZE(lov_dispatch));
 499         ENTRY;
 500
 501         old_ops = &lov_dispatch[obj->lo_type];
 502         new_ops = &lov_dispatch[llt];
 503
 504         result = new_ops->llo_init(env, lu2lov_dev(obj->lo_cl.co_lu.lo_dev),
 505                                    obj, conf, state);
 506         if (result == 0) {
 507                 struct cl_object_header *hdr = cl_object_header(&obj->lo_cl);
 508                 void                    *cookie;
 509                 struct lu_env           *nested;
 510                 int                      refcheck;
 511
 512                 cookie = cl_env_reenter();
 513                 nested = cl_env_get(&refcheck);
 514                 if (!IS_ERR(nested))
 515                         cl_object_prune(nested, &obj->lo_cl);
 516                 else
 517                         result = PTR_ERR(nested);
 518                 cl_env_put(nested, &refcheck);
 519                 cl_env_reexit(cookie);
 520
 521                 old_ops->llo_fini(env, obj, &obj->u);
 522                 LASSERT(cfs_list_empty(&hdr->coh_locks));
 523                 LASSERT(hdr->coh_tree.rnode == NULL);
 524                 LASSERT(hdr->coh_pages == 0);
 525
 526                 new_ops->llo_install(env, obj, state);
 527                 obj->lo_type = llt;
 528         } else
 529                 new_ops->llo_fini(env, obj, state);
 530         RETURN(result);
 531 }
 532
 533 /*****************************************************************************
 534  *
 535  * Lov object operations.
 536  *
 537  */
 538
 539 int lov_object_init(const struct lu_env *env, struct lu_object *obj,
 540                     const struct lu_object_conf *conf)
 541 {
 542         struct lov_device            *dev   = lu2lov_dev(obj->lo_dev);
 543         struct lov_object            *lov   = lu2lov(obj);
 544         const struct cl_object_conf  *cconf = lu2cl_conf(conf);
 545         union  lov_layout_state      *set   = &lov_env_info(env)->lti_state;
 546         const struct lov_layout_operations *ops;
 547         int result;
 548
 549         ENTRY;
 550         cfs_init_rwsem(&lov->lo_type_guard);
 551
 552         /* no locking is necessary, as object is being created */
 553         lov->lo_type = cconf->u.coc_md->lsm != NULL ? LLT_RAID0 : LLT_EMPTY;
 554         ops = &lov_dispatch[lov->lo_type];
 555         result = ops->llo_init(env, dev, lov, cconf, set);
 556         if (result == 0)
 557                 ops->llo_install(env, lov, set);
 558         else
 559                 ops->llo_fini(env, lov, set);
 560         RETURN(result);
 561 }
 562
 563 static int lov_conf_set(const struct lu_env *env, struct cl_object *obj,
 564                         const struct cl_object_conf *conf)
 565 {
 566         struct lov_object *lov = cl2lov(obj);
 567         int result;
 568
 569         ENTRY;
 570         /*
 571          * Currently only LLT_EMPTY -> LLT_RAID0 transition is supported.
 572          */
 573         LASSERT(lov->lo_owner != cfs_current());
 574         cfs_down_write(&lov->lo_type_guard);
 575         LASSERT(lov->lo_owner == NULL);
 576         lov->lo_owner = cfs_current();
 577         if (lov->lo_type == LLT_EMPTY && conf->u.coc_md->lsm != NULL)
 578                 result = lov_layout_change(env, lov, LLT_RAID0, conf);
 579         else
 580                 result = -EOPNOTSUPP;
 581         lov->lo_owner = NULL;
 582         cfs_up_write(&lov->lo_type_guard);
 583         RETURN(result);
 584 }
 585
 586 static void lov_object_delete(const struct lu_env *env, struct lu_object *obj)
 587 {
 588         struct lov_object *lov = lu2lov(obj);
 589
 590         ENTRY;
 591         LOV_2DISPATCH_VOID(lov, llo_delete, env, lov, &lov->u);
 592         EXIT;
 593 }
 594
 595 static void lov_object_free(const struct lu_env *env, struct lu_object *obj)
 596 {
 597         struct lov_object *lov = lu2lov(obj);
 598
 599         ENTRY;
 600         LOV_2DISPATCH_VOID(lov, llo_fini, env, lov, &lov->u);
 601         lu_object_fini(obj);
 602         OBD_SLAB_FREE_PTR(lov, lov_object_kmem);
 603         EXIT;
 604 }
 605
 606 static int lov_object_print(const struct lu_env *env, void *cookie,
 607                             lu_printer_t p, const struct lu_object *o)
 608 {
 609         return LOV_2DISPATCH(lu2lov(o), llo_print, env, cookie, p, o);
 610 }
 611
 612 struct cl_page *lov_page_init(const struct lu_env *env, struct cl_object *obj,
 613                               struct cl_page *page, cfs_page_t *vmpage)
 614 {
 615         return LOV_2DISPATCH(cl2lov(obj),
 616                              llo_page_init, env, obj, page, vmpage);
 617 }
 618
 619 /**
 620  * Implements cl_object_operations::clo_io_init() method for lov
 621  * layer. Dispatches to the appropriate layout io initialization method.
 622  */
 623 int lov_io_init(const struct lu_env *env, struct cl_object *obj,
 624                 struct cl_io *io)
 625 {
 626         CL_IO_SLICE_CLEAN(lov_env_io(env), lis_cl);
 627         /*
 628          * Do not take lock in case of CIT_MISC io, because
 629          *
 630          *     - if this is an io for a glimpse, then we don't care;
 631          *
 632          *     - if this not a glimpse (writepage or lock cancellation), then
 633          *       layout change cannot happen because a page or a lock
 634          *       already exist; and
 635          *
 636          *     - lock ordering (lock mutex nests within layout rw-semaphore)
 637          *       is obeyed in case of lock cancellation.
 638          */
 639         return LOV_2DISPATCH_MAYLOCK(cl2lov(obj), llo_io_init,
 640                                      io->ci_type != CIT_MISC, env, obj, io);
 641 }
 642
 643 /**
 644  * An implementation of cl_object_operations::clo_attr_get() method for lov
 645  * layer. For raid0 layout this collects and merges attributes of all
 646  * sub-objects.
 647  */
 648 static int lov_attr_get(const struct lu_env *env, struct cl_object *obj,
 649                         struct cl_attr *attr)
 650 {
 651         /* do not take lock, as this function is called under a
 652          * spin-lock. Layout is protected from changing by ongoing IO. */
 653         return LOV_2DISPATCH_NOLOCK(cl2lov(obj), llo_getattr, env, obj, attr);
 654 }
 655
 656 static int lov_attr_set(const struct lu_env *env, struct cl_object *obj,
 657                         const struct cl_attr *attr, unsigned valid)
 658 {
 659         /*
 660          * No dispatch is required here, as no layout implements this.
 661          */
 662         return 0;
 663 }
 664
 665 int lov_lock_init(const struct lu_env *env, struct cl_object *obj,
 666                   struct cl_lock *lock, const struct cl_io *io)
 667 {
 668         return LOV_2DISPATCH(cl2lov(obj), llo_lock_init, env, obj, lock, io);
 669 }
 670
 671 static const struct cl_object_operations lov_ops = {
 672         .coo_page_init = lov_page_init,
 673         .coo_lock_init = lov_lock_init,
 674         .coo_io_init   = lov_io_init,
 675         .coo_attr_get  = lov_attr_get,
 676         .coo_attr_set  = lov_attr_set,
 677         .coo_conf_set  = lov_conf_set
 678 };
 679
 680 static const struct lu_object_operations lov_lu_obj_ops = {
 681         .loo_object_init      = lov_object_init,
 682         .loo_object_delete    = lov_object_delete,
 683         .loo_object_release   = NULL,
 684         .loo_object_free      = lov_object_free,
 685         .loo_object_print     = lov_object_print,
 686         .loo_object_invariant = NULL
 687 };
 688
 689 struct lu_object *lov_object_alloc(const struct lu_env *env,
 690                                    const struct lu_object_header *unused,
 691                                    struct lu_device *dev)
 692 {
 693         struct lov_object *lov;
 694         struct lu_object  *obj;
 695
 696         ENTRY;
 697         OBD_SLAB_ALLOC_PTR_GFP(lov, lov_object_kmem, CFS_ALLOC_IO);
 698         if (lov != NULL) {
 699                 obj = lov2lu(lov);
 700                 lu_object_init(obj, NULL, dev);
 701                 lov->lo_cl.co_ops = &lov_ops;
 702                 lov->lo_type = -1; /* invalid, to catch uninitialized type */
 703                 /*
 704                  * object io operation vector (cl_object::co_iop) is installed
 705                  * later in lov_object_init(), as different vectors are used
 706                  * for object with different layouts.
 707                  */
 708                 obj->lo_ops = &lov_lu_obj_ops;
 709         } else
 710                 obj = NULL;
 711         RETURN(obj);
 712 }
 713
 714 /** @} lov */