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 (c) 2008, 2010, Oracle and/or its affiliates. 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 struct cl_object *lov_sub_find(const struct lu_env *env,
 112                                       struct cl_device *dev,
 113                                       const struct lu_fid *fid,
 114                                       const struct cl_object_conf *conf)
 115 {
 116         struct lu_object *o;
 117
 118         ENTRY;
 119         o = lu_object_find_at(env, cl2lu_dev(dev), fid, &conf->coc_lu);
 120         LASSERT(ergo(!IS_ERR(o), o->lo_dev->ld_type == &lovsub_device_type));
 121         RETURN(lu2cl(o));
 122 }
 123
 124 static int lov_init_sub(const struct lu_env *env, struct lov_object *lov,
 125                         struct cl_object *stripe,
 126                         struct lov_layout_raid0 *r0, int idx)
 127 {
 128         struct cl_object_header *hdr;
 129         struct cl_object_header *subhdr;
 130         struct cl_object_header *parent;
 131         struct lov_oinfo        *oinfo;
 132         int result;
 133
 134         hdr    = cl_object_header(lov2cl(lov));
 135         subhdr = cl_object_header(stripe);
 136         parent = subhdr->coh_parent;
 137
 138         oinfo = r0->lo_lsm->lsm_oinfo[idx];
 139         CDEBUG(D_INODE, DFID"@%p[%d] -> "DFID"@%p: id: "LPU64" seq: "LPU64
 140                " idx: %d gen: %d\n",
 141                PFID(&subhdr->coh_lu.loh_fid), subhdr, idx,
 142                PFID(&hdr->coh_lu.loh_fid), hdr,
 143                oinfo->loi_id, oinfo->loi_seq,
 144                oinfo->loi_ost_idx, oinfo->loi_ost_gen);
 145
 146         if (parent == NULL) {
 147                 subhdr->coh_parent = hdr;
 148                 subhdr->coh_nesting = hdr->coh_nesting + 1;
 149                 lu_object_ref_add(&stripe->co_lu, "lov-parent", lov);
 150                 r0->lo_sub[idx] = cl2lovsub(stripe);
 151                 r0->lo_sub[idx]->lso_super = lov;
 152                 r0->lo_sub[idx]->lso_index = idx;
 153                 result = 0;
 154         } else {
 155                 CERROR("Stripe is already owned by other file (%d).\n", idx);
 156                 LU_OBJECT_DEBUG(D_ERROR, env, &stripe->co_lu, "\n");
 157                 LU_OBJECT_DEBUG(D_ERROR, env, lu_object_top(&parent->coh_lu),
 158                                 "old\n");
 159                 LU_OBJECT_HEADER(D_ERROR, env, lov2lu(lov), "new\n");
 160                 cl_object_put(env, stripe);
 161                 result = -EIO;
 162         }
 163         return result;
 164 }
 165
 166 static int lov_init_raid0(const struct lu_env *env,
 167                           struct lov_device *dev, struct lov_object *lov,
 168                           const struct cl_object_conf *conf,
 169                           union  lov_layout_state *state)
 170 {
 171         int result;
 172         int i;
 173
 174         struct cl_object        *stripe;
 175         struct lov_thread_info  *lti     = lov_env_info(env);
 176         struct cl_object_conf   *subconf = &lti->lti_stripe_conf;
 177         struct lov_stripe_md    *lsm     = conf->u.coc_md->lsm;
 178         struct lu_fid           *ofid    = &lti->lti_fid;
 179         struct lov_layout_raid0 *r0      = &state->raid0;
 180
 181         ENTRY;
 182         r0->lo_nr  = conf->u.coc_md->lsm->lsm_stripe_count;
 183         r0->lo_lsm = conf->u.coc_md->lsm;
 184         LASSERT(r0->lo_nr <= lov_targets_nr(dev));
 185
 186         OBD_ALLOC_LARGE(r0->lo_sub, r0->lo_nr * sizeof r0->lo_sub[0]);
 187         if (r0->lo_sub != NULL) {
 188                 result = 0;
 189                 subconf->coc_inode = conf->coc_inode;
 190                 cfs_spin_lock_init(&r0->lo_sub_lock);
 191                 /*
 192                  * Create stripe cl_objects.
 193                  */
 194                 for (i = 0; i < r0->lo_nr && result == 0; ++i) {
 195                         struct cl_device *subdev;
 196                         struct lov_oinfo *oinfo = lsm->lsm_oinfo[i];
 197                         int ost_idx = oinfo->loi_ost_idx;
 198
 199                         fid_ostid_unpack(ofid, &oinfo->loi_oi,
 200                                          oinfo->loi_ost_idx);
 201                         subdev = lovsub2cl_dev(dev->ld_target[ost_idx]);
 202                         subconf->u.coc_oinfo = oinfo;
 203                         LASSERTF(subdev != NULL, "not init ost %d\n", ost_idx);
 204                         stripe = lov_sub_find(env, subdev, ofid, subconf);
 205                         if (!IS_ERR(stripe))
 206                                 result = lov_init_sub(env, lov, stripe, r0, i);
 207                         else
 208                                 result = PTR_ERR(stripe);
 209                 }
 210         } else
 211                 result = -ENOMEM;
 212         RETURN(result);
 213 }
 214
 215 static void lov_delete_empty(const struct lu_env *env, struct lov_object *lov,
 216                              union lov_layout_state *state)
 217 {
 218         LASSERT(lov->lo_type == LLT_EMPTY);
 219 }
 220
 221 static void lov_subobject_kill(const struct lu_env *env, struct lov_object *lov,
 222                                struct lovsub_object *los, int idx)
 223 {
 224         struct cl_object        *sub;
 225         struct lov_layout_raid0 *r0;
 226         struct lu_site          *site;
 227         struct lu_site_bkt_data *bkt;
 228         cfs_waitlink_t          *waiter;
 229
 230         r0  = &lov->u.raid0;
 231         LASSERT(r0->lo_sub[idx] == los);
 232
 233         sub  = lovsub2cl(los);
 234         site = sub->co_lu.lo_dev->ld_site;
 235         bkt  = lu_site_bkt_from_fid(site, &sub->co_lu.lo_header->loh_fid);
 236
 237         cl_object_kill(env, sub);
 238         /* release a reference to the sub-object and ... */
 239         lu_object_ref_del(&sub->co_lu, "lov-parent", lov);
 240         cl_object_put(env, sub);
 241
 242         /* ... wait until it is actually destroyed---sub-object clears its
 243          * ->lo_sub[] slot in lovsub_object_fini() */
 244         if (r0->lo_sub[idx] == los) {
 245                 waiter = &lov_env_info(env)->lti_waiter;
 246                 cfs_waitlink_init(waiter);
 247                 cfs_waitq_add(&bkt->lsb_marche_funebre, waiter);
 248                 cfs_set_current_state(CFS_TASK_UNINT);
 249                 while (1) {
 250                         /* this wait-queue is signaled at the end of
 251                          * lu_object_free(). */
 252                         cfs_set_current_state(CFS_TASK_UNINT);
 253                         cfs_spin_lock(&r0->lo_sub_lock);
 254                         if (r0->lo_sub[idx] == los) {
 255                                 cfs_spin_unlock(&r0->lo_sub_lock);
 256                                 cfs_waitq_wait(waiter, CFS_TASK_UNINT);
 257                         } else {
 258                                 cfs_spin_unlock(&r0->lo_sub_lock);
 259                                 cfs_set_current_state(CFS_TASK_RUNNING);
 260                                 break;
 261                         }
 262                 }
 263                 cfs_waitq_del(&bkt->lsb_marche_funebre, waiter);
 264         }
 265         LASSERT(r0->lo_sub[idx] == NULL);
 266 }
 267
 268 static void lov_delete_raid0(const struct lu_env *env, struct lov_object *lov,
 269                              union lov_layout_state *state)
 270 {
 271         struct lov_layout_raid0 *r0 = &state->raid0;
 272         int                      i;
 273
 274         ENTRY;
 275         if (r0->lo_sub != NULL) {
 276                 for (i = 0; i < r0->lo_nr; ++i) {
 277                         struct lovsub_object *los = r0->lo_sub[i];
 278
 279                         if (los != NULL)
 280                                 /*
 281                                  * If top-level object is to be evicted from
 282                                  * the cache, so are its sub-objects.
 283                                  */
 284                                 lov_subobject_kill(env, lov, los, i);
 285                 }
 286         }
 287         EXIT;
 288 }
 289
 290 static void lov_fini_empty(const struct lu_env *env, struct lov_object *lov,
 291                            union lov_layout_state *state)
 292 {
 293         LASSERT(lov->lo_type == LLT_EMPTY);
 294 }
 295
 296 static void lov_fini_raid0(const struct lu_env *env, struct lov_object *lov,
 297                            union lov_layout_state *state)
 298 {
 299         struct lov_layout_raid0 *r0 = &state->raid0;
 300
 301         ENTRY;
 302         if (r0->lo_sub != NULL) {
 303                 OBD_FREE_LARGE(r0->lo_sub, r0->lo_nr * sizeof r0->lo_sub[0]);
 304                 r0->lo_sub = NULL;
 305         }
 306         EXIT;
 307 }
 308
 309 static int lov_print_empty(const struct lu_env *env, void *cookie,
 310                            lu_printer_t p, const struct lu_object *o)
 311 {
 312         (*p)(env, cookie, "empty\n");
 313         return 0;
 314 }
 315
 316 static int lov_print_raid0(const struct lu_env *env, void *cookie,
 317                            lu_printer_t p, const struct lu_object *o)
 318 {
 319         struct lov_object       *lov = lu2lov(o);
 320         struct lov_layout_raid0 *r0  = lov_r0(lov);
 321         int i;
 322
 323         (*p)(env, cookie, "stripes: %d:\n", r0->lo_nr);
 324         for (i = 0; i < r0->lo_nr; ++i) {
 325                 struct lu_object *sub;
 326
 327                 if (r0->lo_sub[i] != NULL) {
 328                         sub = lovsub2lu(r0->lo_sub[i]);
 329                         lu_object_print(env, cookie, p, sub);
 330                 } else
 331                         (*p)(env, cookie, "sub %d absent\n", i);
 332         }
 333         return 0;
 334 }
 335
 336 /**
 337  * Implements cl_object_operations::coo_attr_get() method for an object
 338  * without stripes (LLT_EMPTY layout type).
 339  *
 340  * The only attributes this layer is authoritative in this case is
 341  * cl_attr::cat_blocks---it's 0.
 342  */
 343 static int lov_attr_get_empty(const struct lu_env *env, struct cl_object *obj,
 344                               struct cl_attr *attr)
 345 {
 346         attr->cat_blocks = 0;
 347         return 0;
 348 }
 349
 350 static int lov_attr_get_raid0(const struct lu_env *env, struct cl_object *obj,
 351                               struct cl_attr *attr)
 352 {
 353         struct lov_object       *lov = cl2lov(obj);
 354         struct lov_layout_raid0 *r0 = lov_r0(lov);
 355         struct lov_stripe_md    *lsm = lov->u.raid0.lo_lsm;
 356         struct ost_lvb          *lvb = &lov_env_info(env)->lti_lvb;
 357         __u64                    kms;
 358         int                      result = 0;
 359
 360         ENTRY;
 361         if (!r0->lo_attr_valid) {
 362                 /*
 363                  * Fill LVB with attributes already initialized by the upper
 364                  * layer.
 365                  */
 366                 cl_attr2lvb(lvb, attr);
 367                 kms = attr->cat_kms;
 368
 369                 /*
 370                  * XXX that should be replaced with a loop over sub-objects,
 371                  * doing cl_object_attr_get() on them. But for now, let's
 372                  * reuse old lov code.
 373                  */
 374
 375                 /*
 376                  * XXX take lsm spin-lock to keep lov_merge_lvb_kms()
 377                  * happy. It's not needed, because new code uses
 378                  * ->coh_attr_guard spin-lock to protect consistency of
 379                  * sub-object attributes.
 380                  */
 381                 lov_stripe_lock(lsm);
 382                 result = lov_merge_lvb_kms(lsm, lvb, &kms);
 383                 lov_stripe_unlock(lsm);
 384                 if (result == 0) {
 385                         cl_lvb2attr(attr, lvb);
 386                         attr->cat_kms = kms;
 387                         r0->lo_attr_valid = 1;
 388                         r0->lo_attr = *attr;
 389                 }
 390         } else
 391                 *attr = r0->lo_attr;
 392         RETURN(result);
 393 }
 394
 395 const static struct lov_layout_operations lov_dispatch[] = {
 396         [LLT_EMPTY] = {
 397                 .llo_init      = lov_init_empty,
 398                 .llo_delete    = lov_delete_empty,
 399                 .llo_fini      = lov_fini_empty,
 400                 .llo_install   = lov_install_empty,
 401                 .llo_print     = lov_print_empty,
 402                 .llo_page_init = lov_page_init_empty,
 403                 .llo_lock_init = NULL,
 404                 .llo_io_init   = lov_io_init_empty,
 405                 .llo_getattr   = lov_attr_get_empty
 406         },
 407         [LLT_RAID0] = {
 408                 .llo_init      = lov_init_raid0,
 409                 .llo_delete    = lov_delete_raid0,
 410                 .llo_fini      = lov_fini_raid0,
 411                 .llo_install   = lov_install_raid0,
 412                 .llo_print     = lov_print_raid0,
 413                 .llo_page_init = lov_page_init_raid0,
 414                 .llo_lock_init = lov_lock_init_raid0,
 415                 .llo_io_init   = lov_io_init_raid0,
 416                 .llo_getattr   = lov_attr_get_raid0
 417         }
 418 };
 419
 420
 421 /**
 422  * Performs a double-dispatch based on the layout type of an object.
 423  */
 424 #define LOV_2DISPATCH_NOLOCK(obj, op, ...)                              \
 425 ({                                                                      \
 426         struct lov_object                      *__obj = (obj);          \
 427         enum lov_layout_type                    __llt;                  \
 428                                                                         \
 429         __llt = __obj->lo_type;                                         \
 430         LASSERT(0 <= __llt && __llt < ARRAY_SIZE(lov_dispatch));        \
 431         lov_dispatch[__llt].op(__VA_ARGS__);                            \
 432 })
 433
 434 #define LOV_2DISPATCH_MAYLOCK(obj, op, lock, ...)                       \
 435 ({                                                                      \
 436         struct lov_object                      *__obj = (obj);          \
 437         int                                     __lock = !!(lock);      \
 438         typeof(lov_dispatch[0].op(__VA_ARGS__)) __result;               \
 439                                                                         \
 440         __lock &= __obj->lo_owner != cfs_current();                     \
 441         if (__lock)                                                     \
 442                 cfs_down_read(&__obj->lo_type_guard);                   \
 443         __result = LOV_2DISPATCH_NOLOCK(obj, op, __VA_ARGS__);          \
 444         if (__lock)                                                     \
 445                 cfs_up_read(&__obj->lo_type_guard);                     \
 446         __result;                                                       \
 447 })
 448
 449 /**
 450  * Performs a locked double-dispatch based on the layout type of an object.
 451  */
 452 #define LOV_2DISPATCH(obj, op, ...)                     \
 453         LOV_2DISPATCH_MAYLOCK(obj, op, 1, __VA_ARGS__)
 454
 455 #define LOV_2DISPATCH_VOID(obj, op, ...)                                \
 456 do {                                                                    \
 457         struct lov_object                      *__obj = (obj);          \
 458         enum lov_layout_type                    __llt;                  \
 459                                                                         \
 460         if (__obj->lo_owner != cfs_current())                           \
 461                 cfs_down_read(&__obj->lo_type_guard);                   \
 462         __llt = __obj->lo_type;                                         \
 463         LASSERT(0 <= __llt && __llt < ARRAY_SIZE(lov_dispatch));        \
 464         lov_dispatch[__llt].op(__VA_ARGS__);                            \
 465         if (__obj->lo_owner != cfs_current())                           \
 466                 cfs_up_read(&__obj->lo_type_guard);                     \
 467 } while (0)
 468
 469 static int lov_layout_change(const struct lu_env *env,
 470                              struct lov_object *obj, enum lov_layout_type llt,
 471                              const struct cl_object_conf *conf)
 472 {
 473         int result;
 474         union lov_layout_state       *state = &lov_env_info(env)->lti_state;
 475         const struct lov_layout_operations *old_ops;
 476         const struct lov_layout_operations *new_ops;
 477
 478         LASSERT(0 <= obj->lo_type && obj->lo_type < ARRAY_SIZE(lov_dispatch));
 479         LASSERT(0 <= llt && llt < ARRAY_SIZE(lov_dispatch));
 480         ENTRY;
 481
 482         old_ops = &lov_dispatch[obj->lo_type];
 483         new_ops = &lov_dispatch[llt];
 484
 485         result = new_ops->llo_init(env, lu2lov_dev(obj->lo_cl.co_lu.lo_dev),
 486                                    obj, conf, state);
 487         if (result == 0) {
 488                 struct cl_object_header *hdr = cl_object_header(&obj->lo_cl);
 489                 void                    *cookie;
 490                 struct lu_env           *nested;
 491                 int                      refcheck;
 492
 493                 cookie = cl_env_reenter();
 494                 nested = cl_env_get(&refcheck);
 495                 if (!IS_ERR(nested))
 496                         cl_object_prune(nested, &obj->lo_cl);
 497                 else
 498                         result = PTR_ERR(nested);
 499                 cl_env_put(nested, &refcheck);
 500                 cl_env_reexit(cookie);
 501
 502                 old_ops->llo_fini(env, obj, &obj->u);
 503                 LASSERT(cfs_list_empty(&hdr->coh_locks));
 504                 LASSERT(hdr->coh_tree.rnode == NULL);
 505                 LASSERT(hdr->coh_pages == 0);
 506
 507                 new_ops->llo_install(env, obj, state);
 508                 obj->lo_type = llt;
 509         } else
 510                 new_ops->llo_fini(env, obj, state);
 511         RETURN(result);
 512 }
 513
 514 /*****************************************************************************
 515  *
 516  * Lov object operations.
 517  *
 518  */
 519
 520 int lov_object_init(const struct lu_env *env, struct lu_object *obj,
 521                     const struct lu_object_conf *conf)
 522 {
 523         struct lov_device            *dev   = lu2lov_dev(obj->lo_dev);
 524         struct lov_object            *lov   = lu2lov(obj);
 525         const struct cl_object_conf  *cconf = lu2cl_conf(conf);
 526         union  lov_layout_state      *set   = &lov_env_info(env)->lti_state;
 527         const struct lov_layout_operations *ops;
 528         int result;
 529
 530         ENTRY;
 531         cfs_init_rwsem(&lov->lo_type_guard);
 532
 533         /* no locking is necessary, as object is being created */
 534         lov->lo_type = cconf->u.coc_md->lsm != NULL ? LLT_RAID0 : LLT_EMPTY;
 535         ops = &lov_dispatch[lov->lo_type];
 536         result = ops->llo_init(env, dev, lov, cconf, set);
 537         if (result == 0)
 538                 ops->llo_install(env, lov, set);
 539         else
 540                 ops->llo_fini(env, lov, set);
 541         RETURN(result);
 542 }
 543
 544 static int lov_conf_set(const struct lu_env *env, struct cl_object *obj,
 545                         const struct cl_object_conf *conf)
 546 {
 547         struct lov_object *lov = cl2lov(obj);
 548         int result;
 549
 550         ENTRY;
 551         /*
 552          * Currently only LLT_EMPTY -> LLT_RAID0 transition is supported.
 553          */
 554         LASSERT(lov->lo_owner != cfs_current());
 555         cfs_down_write(&lov->lo_type_guard);
 556         LASSERT(lov->lo_owner == NULL);
 557         lov->lo_owner = cfs_current();
 558         if (lov->lo_type == LLT_EMPTY && conf->u.coc_md->lsm != NULL)
 559                 result = lov_layout_change(env, lov, LLT_RAID0, conf);
 560         else
 561                 result = -EOPNOTSUPP;
 562         lov->lo_owner = NULL;
 563         cfs_up_write(&lov->lo_type_guard);
 564         RETURN(result);
 565 }
 566
 567 static void lov_object_delete(const struct lu_env *env, struct lu_object *obj)
 568 {
 569         struct lov_object *lov = lu2lov(obj);
 570
 571         ENTRY;
 572         LOV_2DISPATCH_VOID(lov, llo_delete, env, lov, &lov->u);
 573         EXIT;
 574 }
 575
 576 static void lov_object_free(const struct lu_env *env, struct lu_object *obj)
 577 {
 578         struct lov_object *lov = lu2lov(obj);
 579
 580         ENTRY;
 581         LOV_2DISPATCH_VOID(lov, llo_fini, env, lov, &lov->u);
 582         lu_object_fini(obj);
 583         OBD_SLAB_FREE_PTR(lov, lov_object_kmem);
 584         EXIT;
 585 }
 586
 587 static int lov_object_print(const struct lu_env *env, void *cookie,
 588                             lu_printer_t p, const struct lu_object *o)
 589 {
 590         return LOV_2DISPATCH(lu2lov(o), llo_print, env, cookie, p, o);
 591 }
 592
 593 struct cl_page *lov_page_init(const struct lu_env *env, struct cl_object *obj,
 594                               struct cl_page *page, cfs_page_t *vmpage)
 595 {
 596         return LOV_2DISPATCH(cl2lov(obj),
 597                              llo_page_init, env, obj, page, vmpage);
 598 }
 599
 600 /**
 601  * Implements cl_object_operations::clo_io_init() method for lov
 602  * layer. Dispatches to the appropriate layout io initialization method.
 603  */
 604 int lov_io_init(const struct lu_env *env, struct cl_object *obj,
 605                 struct cl_io *io)
 606 {
 607         CL_IO_SLICE_CLEAN(lov_env_io(env), lis_cl);
 608         /*
 609          * Do not take lock in case of CIT_MISC io, because
 610          *
 611          *     - if this is an io for a glimpse, then we don't care;
 612          *
 613          *     - if this not a glimpse (writepage or lock cancellation), then
 614          *       layout change cannot happen because a page or a lock
 615          *       already exist; and
 616          *
 617          *     - lock ordering (lock mutex nests within layout rw-semaphore)
 618          *       is obeyed in case of lock cancellation.
 619          */
 620         return LOV_2DISPATCH_MAYLOCK(cl2lov(obj), llo_io_init,
 621                                      io->ci_type != CIT_MISC, env, obj, io);
 622 }
 623
 624 /**
 625  * An implementation of cl_object_operations::clo_attr_get() method for lov
 626  * layer. For raid0 layout this collects and merges attributes of all
 627  * sub-objects.
 628  */
 629 static int lov_attr_get(const struct lu_env *env, struct cl_object *obj,
 630                         struct cl_attr *attr)
 631 {
 632         /* do not take lock, as this function is called under a
 633          * spin-lock. Layout is protected from changing by ongoing IO. */
 634         return LOV_2DISPATCH_NOLOCK(cl2lov(obj), llo_getattr, env, obj, attr);
 635 }
 636
 637 static int lov_attr_set(const struct lu_env *env, struct cl_object *obj,
 638                         const struct cl_attr *attr, unsigned valid)
 639 {
 640         /*
 641          * No dispatch is required here, as no layout implements this.
 642          */
 643         return 0;
 644 }
 645
 646 int lov_lock_init(const struct lu_env *env, struct cl_object *obj,
 647                   struct cl_lock *lock, const struct cl_io *io)
 648 {
 649         return LOV_2DISPATCH(cl2lov(obj), llo_lock_init, env, obj, lock, io);
 650 }
 651
 652 static const struct cl_object_operations lov_ops = {
 653         .coo_page_init = lov_page_init,
 654         .coo_lock_init = lov_lock_init,
 655         .coo_io_init   = lov_io_init,
 656         .coo_attr_get  = lov_attr_get,
 657         .coo_attr_set  = lov_attr_set,
 658         .coo_conf_set  = lov_conf_set
 659 };
 660
 661 static const struct lu_object_operations lov_lu_obj_ops = {
 662         .loo_object_init      = lov_object_init,
 663         .loo_object_delete    = lov_object_delete,
 664         .loo_object_release   = NULL,
 665         .loo_object_free      = lov_object_free,
 666         .loo_object_print     = lov_object_print,
 667         .loo_object_invariant = NULL
 668 };
 669
 670 struct lu_object *lov_object_alloc(const struct lu_env *env,
 671                                    const struct lu_object_header *unused,
 672                                    struct lu_device *dev)
 673 {
 674         struct lov_object *lov;
 675         struct lu_object  *obj;
 676
 677         ENTRY;
 678         OBD_SLAB_ALLOC_PTR_GFP(lov, lov_object_kmem, CFS_ALLOC_IO);
 679         if (lov != NULL) {
 680                 obj = lov2lu(lov);
 681                 lu_object_init(obj, NULL, dev);
 682                 lov->lo_cl.co_ops = &lov_ops;
 683                 lov->lo_type = -1; /* invalid, to catch uninitialized type */
 684                 /*
 685                  * object io operation vector (cl_object::co_iop) is installed
 686                  * later in lov_object_init(), as different vectors are used
 687                  * for object with different layouts.
 688                  */
 689                 obj->lo_ops = &lov_lu_obj_ops;
 690         } else
 691                 obj = NULL;
 692         RETURN(obj);
 693 }
 694
 695 /** @} lov */