lustre/lov/lov_object.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) 2008, 2010, Oracle and/or its affiliates. All rights reserved.
  28  * Use is subject to license terms.
  29  *
  30  * Copyright (c) 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  * Implementation of cl_object for LOV layer.
  37  *
  38  *   Author: Nikita Danilov <nikita.danilov@sun.com>
  39  *   Author: Jinshan Xiong <jinshan.xiong@whamcloud.com>
  40  */
  41
  42 #define DEBUG_SUBSYSTEM S_LOV
  43
  44 #include "lov_cl_internal.h"
  45 #include <lustre_debug.h>
  46
  47 /** \addtogroup lov
  48  *  @{
  49  */
  50
  51 /*****************************************************************************
  52  *
  53  * Layout operations.
  54  *
  55  */
  56
  57 struct lov_layout_operations {
  58         int (*llo_init)(const struct lu_env *env, struct lov_device *dev,
  59                         struct lov_object *lov,
  60                         const struct cl_object_conf *conf,
  61                         union lov_layout_state *state);
  62         void (*llo_delete)(const struct lu_env *env, struct lov_object *lov,
  63                            union lov_layout_state *state);
  64         void (*llo_fini)(const struct lu_env *env, struct lov_object *lov,
  65                          union lov_layout_state *state);
  66         void (*llo_install)(const struct lu_env *env, struct lov_object *lov,
  67                             union lov_layout_state *state);
  68         int  (*llo_print)(const struct lu_env *env, void *cookie,
  69                           lu_printer_t p, const struct lu_object *o);
  70         struct cl_page *(*llo_page_init)(const struct lu_env *env,
  71                                          struct cl_object *obj,
  72                                          struct cl_page *page,
  73                                          cfs_page_t *vmpage);
  74         int  (*llo_lock_init)(const struct lu_env *env,
  75                               struct cl_object *obj, struct cl_lock *lock,
  76                               const struct cl_io *io);
  77         int  (*llo_io_init)(const struct lu_env *env,
  78                             struct cl_object *obj, struct cl_io *io);
  79         int  (*llo_getattr)(const struct lu_env *env, struct cl_object *obj,
  80                             struct cl_attr *attr);
  81 };
  82
  83 /*****************************************************************************
  84  *
  85  * Lov object layout operations.
  86  *
  87  */
  88
  89 static void lov_install_empty(const struct lu_env *env,
  90                               struct lov_object *lov,
  91                               union  lov_layout_state *state)
  92 {
  93         /*
  94          * File without objects.
  95          */
  96 }
  97
  98 static int lov_init_empty(const struct lu_env *env,
  99                           struct lov_device *dev, struct lov_object *lov,
 100                           const struct cl_object_conf *conf,
 101                           union  lov_layout_state *state)
 102 {
 103         return 0;
 104 }
 105
 106 static void lov_install_raid0(const struct lu_env *env,
 107                               struct lov_object *lov,
 108                               union  lov_layout_state *state)
 109 {
 110         lov->u = *state;
 111 }
 112
 113 static struct cl_object *lov_sub_find(const struct lu_env *env,
 114                                       struct cl_device *dev,
 115                                       const struct lu_fid *fid,
 116                                       const struct cl_object_conf *conf)
 117 {
 118         struct lu_object *o;
 119
 120         ENTRY;
 121         o = lu_object_find_at(env, cl2lu_dev(dev), fid, &conf->coc_lu);
 122         LASSERT(ergo(!IS_ERR(o), o->lo_dev->ld_type == &lovsub_device_type));
 123         RETURN(lu2cl(o));
 124 }
 125
 126 static int lov_init_sub(const struct lu_env *env, struct lov_object *lov,
 127                         struct cl_object *stripe,
 128                         struct lov_layout_raid0 *r0, int idx)
 129 {
 130         struct cl_object_header *hdr;
 131         struct cl_object_header *subhdr;
 132         struct cl_object_header *parent;
 133         struct lov_oinfo        *oinfo;
 134         int result;
 135
 136         hdr    = cl_object_header(lov2cl(lov));
 137         subhdr = cl_object_header(stripe);
 138         parent = subhdr->coh_parent;
 139
 140         oinfo = r0->lo_lsm->lsm_oinfo[idx];
 141         CDEBUG(D_INODE, DFID"@%p[%d] -> "DFID"@%p: id: "LPU64" seq: "LPU64
 142                " idx: %d gen: %d\n",
 143                PFID(&subhdr->coh_lu.loh_fid), subhdr, idx,
 144                PFID(&hdr->coh_lu.loh_fid), hdr,
 145                oinfo->loi_id, oinfo->loi_seq,
 146                oinfo->loi_ost_idx, oinfo->loi_ost_gen);
 147
 148         if (parent == NULL) {
 149                 subhdr->coh_parent = hdr;
 150                 subhdr->coh_nesting = hdr->coh_nesting + 1;
 151                 lu_object_ref_add(&stripe->co_lu, "lov-parent", lov);
 152                 r0->lo_sub[idx] = cl2lovsub(stripe);
 153                 r0->lo_sub[idx]->lso_super = lov;
 154                 r0->lo_sub[idx]->lso_index = idx;
 155                 result = 0;
 156         } else {
 157                 CERROR("Stripe is already owned by other file (%d).\n", idx);
 158                 LU_OBJECT_DEBUG(D_ERROR, env, &stripe->co_lu, "\n");
 159                 LU_OBJECT_DEBUG(D_ERROR, env, lu_object_top(&parent->coh_lu),
 160                                 "old\n");
 161                 LU_OBJECT_HEADER(D_ERROR, env, lov2lu(lov), "new\n");
 162                 cl_object_put(env, stripe);
 163                 result = -EIO;
 164         }
 165         return result;
 166 }
 167
 168 static int lov_init_raid0(const struct lu_env *env,
 169                           struct lov_device *dev, struct lov_object *lov,
 170                           const struct cl_object_conf *conf,
 171                           union  lov_layout_state *state)
 172 {
 173         int result;
 174         int i;
 175
 176         struct cl_object        *stripe;
 177         struct lov_thread_info  *lti     = lov_env_info(env);
 178         struct cl_object_conf   *subconf = &lti->lti_stripe_conf;
 179         struct lov_stripe_md    *lsm     = conf->u.coc_md->lsm;
 180         struct lu_fid           *ofid    = &lti->lti_fid;
 181         struct lov_layout_raid0 *r0      = &state->raid0;
 182
 183         ENTRY;
 184
 185         if (lsm->lsm_magic != LOV_MAGIC_V1 && lsm->lsm_magic != LOV_MAGIC_V3) {
 186                 dump_lsm(D_ERROR, lsm);
 187                 LASSERTF(0, "magic mismatch, expected %d/%d, actual %d.\n",
 188                          LOV_MAGIC_V1, LOV_MAGIC_V3, lsm->lsm_magic);
 189         }
 190
 191         r0->lo_lsm = lsm_addref(lsm);
 192         r0->lo_nr  = lsm->lsm_stripe_count;
 193         LASSERT(r0->lo_nr <= lov_targets_nr(dev));
 194
 195         OBD_ALLOC_LARGE(r0->lo_sub, r0->lo_nr * sizeof r0->lo_sub[0]);
 196         if (r0->lo_sub != NULL) {
 197                 result = 0;
 198                 subconf->coc_inode = conf->coc_inode;
 199                 cfs_spin_lock_init(&r0->lo_sub_lock);
 200                 /*
 201                  * Create stripe cl_objects.
 202                  */
 203                 for (i = 0; i < r0->lo_nr && result == 0; ++i) {
 204                         struct cl_device *subdev;
 205                         struct lov_oinfo *oinfo = lsm->lsm_oinfo[i];
 206                         int ost_idx = oinfo->loi_ost_idx;
 207
 208                         fid_ostid_unpack(ofid, &oinfo->loi_oi,
 209                                          oinfo->loi_ost_idx);
 210                         subdev = lovsub2cl_dev(dev->ld_target[ost_idx]);
 211                         subconf->u.coc_oinfo = oinfo;
 212                         LASSERTF(subdev != NULL, "not init ost %d\n", ost_idx);
 213                         stripe = lov_sub_find(env, subdev, ofid, subconf);
 214                         if (!IS_ERR(stripe))
 215                                 result = lov_init_sub(env, lov, stripe, r0, i);
 216                         else
 217                                 result = PTR_ERR(stripe);
 218                 }
 219         } else
 220                 result = -ENOMEM;
 221         RETURN(result);
 222 }
 223
 224 static void lov_delete_empty(const struct lu_env *env, struct lov_object *lov,
 225                              union lov_layout_state *state)
 226 {
 227         LASSERT(lov->lo_type == LLT_EMPTY);
 228 }
 229
 230 static void lov_subobject_kill(const struct lu_env *env, struct lov_object *lov,
 231                                struct lovsub_object *los, int idx)
 232 {
 233         struct cl_object        *sub;
 234         struct lov_layout_raid0 *r0;
 235         struct lu_site          *site;
 236         struct lu_site_bkt_data *bkt;
 237         cfs_waitlink_t          *waiter;
 238
 239         r0  = &lov->u.raid0;
 240         LASSERT(r0->lo_sub[idx] == los);
 241
 242         sub  = lovsub2cl(los);
 243         site = sub->co_lu.lo_dev->ld_site;
 244         bkt  = lu_site_bkt_from_fid(site, &sub->co_lu.lo_header->loh_fid);
 245
 246         cl_object_kill(env, sub);
 247         /* release a reference to the sub-object and ... */
 248         lu_object_ref_del(&sub->co_lu, "lov-parent", lov);
 249         cl_object_put(env, sub);
 250
 251         /* ... wait until it is actually destroyed---sub-object clears its
 252          * ->lo_sub[] slot in lovsub_object_fini() */
 253         if (r0->lo_sub[idx] == los) {
 254                 waiter = &lov_env_info(env)->lti_waiter;
 255                 cfs_waitlink_init(waiter);
 256                 cfs_waitq_add(&bkt->lsb_marche_funebre, waiter);
 257                 cfs_set_current_state(CFS_TASK_UNINT);
 258                 while (1) {
 259                         /* this wait-queue is signaled at the end of
 260                          * lu_object_free(). */
 261                         cfs_set_current_state(CFS_TASK_UNINT);
 262                         cfs_spin_lock(&r0->lo_sub_lock);
 263                         if (r0->lo_sub[idx] == los) {
 264                                 cfs_spin_unlock(&r0->lo_sub_lock);
 265                                 cfs_waitq_wait(waiter, CFS_TASK_UNINT);
 266                         } else {
 267                                 cfs_spin_unlock(&r0->lo_sub_lock);
 268                                 cfs_set_current_state(CFS_TASK_RUNNING);
 269                                 break;
 270                         }
 271                 }
 272                 cfs_waitq_del(&bkt->lsb_marche_funebre, waiter);
 273         }
 274         LASSERT(r0->lo_sub[idx] == NULL);
 275 }
 276
 277 static void lov_delete_raid0(const struct lu_env *env, struct lov_object *lov,
 278                              union lov_layout_state *state)
 279 {
 280         struct lov_layout_raid0 *r0 = &state->raid0;
 281         struct lov_stripe_md    *lsm = r0->lo_lsm;
 282         struct l_wait_info       lwi = { 0 };
 283         int                      i;
 284
 285         ENTRY;
 286
 287         /* wait until there is no extra users. */
 288         dump_lsm(D_INODE, lsm);
 289         l_wait_event(lov->lo_waitq, cfs_atomic_read(&lsm->lsm_refc) == 1, &lwi);
 290
 291         if (r0->lo_sub != NULL) {
 292                 for (i = 0; i < r0->lo_nr; ++i) {
 293                         struct lovsub_object *los = r0->lo_sub[i];
 294
 295                         if (los != NULL)
 296                                 /*
 297                                  * If top-level object is to be evicted from
 298                                  * the cache, so are its sub-objects.
 299                                  */
 300                                 lov_subobject_kill(env, lov, los, i);
 301                 }
 302         }
 303         EXIT;
 304 }
 305
 306 static void lov_fini_empty(const struct lu_env *env, struct lov_object *lov,
 307                            union lov_layout_state *state)
 308 {
 309         LASSERT(lov->lo_type == LLT_EMPTY);
 310 }
 311
 312 static void lov_fini_raid0(const struct lu_env *env, struct lov_object *lov,
 313                            union lov_layout_state *state)
 314 {
 315         struct lov_layout_raid0 *r0 = &state->raid0;
 316
 317         ENTRY;
 318
 319         if (r0->lo_sub != NULL) {
 320                 OBD_FREE_LARGE(r0->lo_sub, r0->lo_nr * sizeof r0->lo_sub[0]);
 321                 r0->lo_sub = NULL;
 322         }
 323
 324         LASSERT(cfs_atomic_read(&r0->lo_lsm->lsm_refc) == 1);
 325         lov_free_memmd(&r0->lo_lsm);
 326
 327         EXIT;
 328 }
 329
 330 static int lov_print_empty(const struct lu_env *env, void *cookie,
 331                            lu_printer_t p, const struct lu_object *o)
 332 {
 333         (*p)(env, cookie, "empty\n");
 334         return 0;
 335 }
 336
 337 static int lov_print_raid0(const struct lu_env *env, void *cookie,
 338                            lu_printer_t p, const struct lu_object *o)
 339 {
 340         struct lov_object       *lov = lu2lov(o);
 341         struct lov_layout_raid0 *r0  = lov_r0(lov);
 342         int i;
 343
 344         (*p)(env, cookie, "stripes: %d:\n", r0->lo_nr);
 345         for (i = 0; i < r0->lo_nr; ++i) {
 346                 struct lu_object *sub;
 347
 348                 if (r0->lo_sub[i] != NULL) {
 349                         sub = lovsub2lu(r0->lo_sub[i]);
 350                         lu_object_print(env, cookie, p, sub);
 351                 } else
 352                         (*p)(env, cookie, "sub %d absent\n", i);
 353         }
 354         return 0;
 355 }
 356
 357 /**
 358  * Implements cl_object_operations::coo_attr_get() method for an object
 359  * without stripes (LLT_EMPTY layout type).
 360  *
 361  * The only attributes this layer is authoritative in this case is
 362  * cl_attr::cat_blocks---it's 0.
 363  */
 364 static int lov_attr_get_empty(const struct lu_env *env, struct cl_object *obj,
 365                               struct cl_attr *attr)
 366 {
 367         attr->cat_blocks = 0;
 368         return 0;
 369 }
 370
 371 static int lov_attr_get_raid0(const struct lu_env *env, struct cl_object *obj,
 372                               struct cl_attr *attr)
 373 {
 374         struct lov_object       *lov = cl2lov(obj);
 375         struct lov_layout_raid0 *r0 = lov_r0(lov);
 376         struct lov_stripe_md    *lsm = lov->u.raid0.lo_lsm;
 377         struct ost_lvb          *lvb = &lov_env_info(env)->lti_lvb;
 378         __u64                    kms;
 379         int                      result = 0;
 380
 381         ENTRY;
 382         if (!r0->lo_attr_valid) {
 383                 /*
 384                  * Fill LVB with attributes already initialized by the upper
 385                  * layer.
 386                  */
 387                 cl_attr2lvb(lvb, attr);
 388                 kms = attr->cat_kms;
 389
 390                 /*
 391                  * XXX that should be replaced with a loop over sub-objects,
 392                  * doing cl_object_attr_get() on them. But for now, let's
 393                  * reuse old lov code.
 394                  */
 395
 396                 /*
 397                  * XXX take lsm spin-lock to keep lov_merge_lvb_kms()
 398                  * happy. It's not needed, because new code uses
 399                  * ->coh_attr_guard spin-lock to protect consistency of
 400                  * sub-object attributes.
 401                  */
 402                 lov_stripe_lock(lsm);
 403                 result = lov_merge_lvb_kms(lsm, lvb, &kms);
 404                 lov_stripe_unlock(lsm);
 405                 if (result == 0) {
 406                         cl_lvb2attr(attr, lvb);
 407                         attr->cat_kms = kms;
 408                         r0->lo_attr_valid = 1;
 409                         r0->lo_attr = *attr;
 410                 }
 411         } else
 412                 *attr = r0->lo_attr;
 413         RETURN(result);
 414 }
 415
 416 const static struct lov_layout_operations lov_dispatch[] = {
 417         [LLT_EMPTY] = {
 418                 .llo_init      = lov_init_empty,
 419                 .llo_delete    = lov_delete_empty,
 420                 .llo_fini      = lov_fini_empty,
 421                 .llo_install   = lov_install_empty,
 422                 .llo_print     = lov_print_empty,
 423                 .llo_page_init = lov_page_init_empty,
 424                 .llo_lock_init = NULL,
 425                 .llo_io_init   = lov_io_init_empty,
 426                 .llo_getattr   = lov_attr_get_empty
 427         },
 428         [LLT_RAID0] = {
 429                 .llo_init      = lov_init_raid0,
 430                 .llo_delete    = lov_delete_raid0,
 431                 .llo_fini      = lov_fini_raid0,
 432                 .llo_install   = lov_install_raid0,
 433                 .llo_print     = lov_print_raid0,
 434                 .llo_page_init = lov_page_init_raid0,
 435                 .llo_lock_init = lov_lock_init_raid0,
 436                 .llo_io_init   = lov_io_init_raid0,
 437                 .llo_getattr   = lov_attr_get_raid0
 438         }
 439 };
 440
 441
 442 /**
 443  * Performs a double-dispatch based on the layout type of an object.
 444  */
 445 #define LOV_2DISPATCH_NOLOCK(obj, op, ...)                              \
 446 ({                                                                      \
 447         struct lov_object                      *__obj = (obj);          \
 448         enum lov_layout_type                    __llt;                  \
 449                                                                         \
 450         __llt = __obj->lo_type;                                         \
 451         LASSERT(0 <= __llt && __llt < ARRAY_SIZE(lov_dispatch));        \
 452         lov_dispatch[__llt].op(__VA_ARGS__);                            \
 453 })
 454
 455 #define LOV_2DISPATCH_MAYLOCK(obj, op, lock, ...)                       \
 456 ({                                                                      \
 457         struct lov_object                      *__obj = (obj);          \
 458         int                                     __lock = !!(lock);      \
 459         typeof(lov_dispatch[0].op(__VA_ARGS__)) __result;               \
 460                                                                         \
 461         __lock &= __obj->lo_owner != cfs_current();                     \
 462         if (__lock)                                                     \
 463                 cfs_down_read(&__obj->lo_type_guard);                   \
 464         __result = LOV_2DISPATCH_NOLOCK(obj, op, __VA_ARGS__);          \
 465         if (__lock)                                                     \
 466                 cfs_up_read(&__obj->lo_type_guard);                     \
 467         __result;                                                       \
 468 })
 469
 470 /**
 471  * Performs a locked double-dispatch based on the layout type of an object.
 472  */
 473 #define LOV_2DISPATCH(obj, op, ...)                     \
 474         LOV_2DISPATCH_MAYLOCK(obj, op, 1, __VA_ARGS__)
 475
 476 #define LOV_2DISPATCH_VOID(obj, op, ...)                                \
 477 do {                                                                    \
 478         struct lov_object                      *__obj = (obj);          \
 479         enum lov_layout_type                    __llt;                  \
 480                                                                         \
 481         if (__obj->lo_owner != cfs_current())                           \
 482                 cfs_down_read(&__obj->lo_type_guard);                   \
 483         __llt = __obj->lo_type;                                         \
 484         LASSERT(0 <= __llt && __llt < ARRAY_SIZE(lov_dispatch));        \
 485         lov_dispatch[__llt].op(__VA_ARGS__);                            \
 486         if (__obj->lo_owner != cfs_current())                           \
 487                 cfs_up_read(&__obj->lo_type_guard);                     \
 488 } while (0)
 489
 490 static int lov_layout_change(const struct lu_env *env,
 491                              struct lov_object *obj, enum lov_layout_type llt,
 492                              const struct cl_object_conf *conf)
 493 {
 494         int result;
 495         union lov_layout_state       *state = &lov_env_info(env)->lti_state;
 496         const struct lov_layout_operations *old_ops;
 497         const struct lov_layout_operations *new_ops;
 498
 499         LASSERT(0 <= obj->lo_type && obj->lo_type < ARRAY_SIZE(lov_dispatch));
 500         LASSERT(0 <= llt && llt < ARRAY_SIZE(lov_dispatch));
 501         ENTRY;
 502
 503         old_ops = &lov_dispatch[obj->lo_type];
 504         new_ops = &lov_dispatch[llt];
 505
 506         result = new_ops->llo_init(env, lu2lov_dev(obj->lo_cl.co_lu.lo_dev),
 507                                    obj, conf, state);
 508         if (result == 0) {
 509                 struct cl_object_header *hdr = cl_object_header(&obj->lo_cl);
 510                 void                    *cookie;
 511                 struct lu_env           *nested;
 512                 int                      refcheck;
 513
 514                 cookie = cl_env_reenter();
 515                 nested = cl_env_get(&refcheck);
 516                 if (!IS_ERR(nested))
 517                         cl_object_prune(nested, &obj->lo_cl);
 518                 else
 519                         result = PTR_ERR(nested);
 520                 cl_env_put(nested, &refcheck);
 521                 cl_env_reexit(cookie);
 522
 523                 old_ops->llo_delete(env, obj, &obj->u);
 524                 old_ops->llo_fini(env, obj, &obj->u);
 525                 LASSERT(cfs_list_empty(&hdr->coh_locks));
 526                 LASSERT(hdr->coh_tree.rnode == NULL);
 527                 LASSERT(hdr->coh_pages == 0);
 528
 529                 new_ops->llo_install(env, obj, state);
 530                 obj->lo_type = llt;
 531         } else
 532                 new_ops->llo_fini(env, obj, state);
 533         RETURN(result);
 534 }
 535
 536 /*****************************************************************************
 537  *
 538  * Lov object operations.
 539  *
 540  */
 541
 542 int lov_object_init(const struct lu_env *env, struct lu_object *obj,
 543                     const struct lu_object_conf *conf)
 544 {
 545         struct lov_device            *dev   = lu2lov_dev(obj->lo_dev);
 546         struct lov_object            *lov   = lu2lov(obj);
 547         const struct cl_object_conf  *cconf = lu2cl_conf(conf);
 548         union  lov_layout_state      *set   = &lov_env_info(env)->lti_state;
 549         const struct lov_layout_operations *ops;
 550         int result;
 551
 552         ENTRY;
 553         cfs_init_rwsem(&lov->lo_type_guard);
 554         cfs_waitq_init(&lov->lo_waitq);
 555
 556         /* no locking is necessary, as object is being created */
 557         lov->lo_type = cconf->u.coc_md->lsm != NULL ? LLT_RAID0 : LLT_EMPTY;
 558         ops = &lov_dispatch[lov->lo_type];
 559         result = ops->llo_init(env, dev, lov, cconf, set);
 560         if (result == 0)
 561                 ops->llo_install(env, lov, set);
 562         else
 563                 ops->llo_fini(env, lov, set);
 564         RETURN(result);
 565 }
 566
 567 static int lov_conf_set(const struct lu_env *env, struct cl_object *obj,
 568                         const struct cl_object_conf *conf)
 569 {
 570         struct lov_stripe_md *lsm = conf->u.coc_md->lsm;
 571         struct lov_object *lov = cl2lov(obj);
 572         int result = 0;
 573
 574         ENTRY;
 575         /*
 576          * Currently only LLT_EMPTY -> LLT_RAID0 transition is supported.
 577          */
 578         LASSERT(lov->lo_owner != cfs_current());
 579         cfs_down_write(&lov->lo_type_guard);
 580         LASSERT(lov->lo_owner == NULL);
 581         lov->lo_owner = cfs_current();
 582         switch (lov->lo_type) {
 583         case LLT_EMPTY:
 584                 if (lsm != NULL)
 585                         result = lov_layout_change(env, lov, LLT_RAID0, conf);
 586                 break;
 587         case LLT_RAID0:
 588                 if (lsm == NULL || lov_stripe_md_cmp(lov->u.raid0.lo_lsm, lsm))
 589                         result = -EOPNOTSUPP;
 590                 break;
 591         default:
 592                 LBUG();
 593         }
 594         lov->lo_owner = NULL;
 595         cfs_up_write(&lov->lo_type_guard);
 596         RETURN(result);
 597 }
 598
 599 static void lov_object_delete(const struct lu_env *env, struct lu_object *obj)
 600 {
 601         struct lov_object *lov = lu2lov(obj);
 602
 603         ENTRY;
 604         LOV_2DISPATCH_VOID(lov, llo_delete, env, lov, &lov->u);
 605         EXIT;
 606 }
 607
 608 static void lov_object_free(const struct lu_env *env, struct lu_object *obj)
 609 {
 610         struct lov_object *lov = lu2lov(obj);
 611
 612         ENTRY;
 613         LOV_2DISPATCH_VOID(lov, llo_fini, env, lov, &lov->u);
 614         lu_object_fini(obj);
 615         OBD_SLAB_FREE_PTR(lov, lov_object_kmem);
 616         EXIT;
 617 }
 618
 619 static int lov_object_print(const struct lu_env *env, void *cookie,
 620                             lu_printer_t p, const struct lu_object *o)
 621 {
 622         return LOV_2DISPATCH(lu2lov(o), llo_print, env, cookie, p, o);
 623 }
 624
 625 struct cl_page *lov_page_init(const struct lu_env *env, struct cl_object *obj,
 626                               struct cl_page *page, cfs_page_t *vmpage)
 627 {
 628         return LOV_2DISPATCH(cl2lov(obj),
 629                              llo_page_init, env, obj, page, vmpage);
 630 }
 631
 632 /**
 633  * Implements cl_object_operations::clo_io_init() method for lov
 634  * layer. Dispatches to the appropriate layout io initialization method.
 635  */
 636 int lov_io_init(const struct lu_env *env, struct cl_object *obj,
 637                 struct cl_io *io)
 638 {
 639         CL_IO_SLICE_CLEAN(lov_env_io(env), lis_cl);
 640         /*
 641          * Do not take lock in case of CIT_MISC io, because
 642          *
 643          *     - if this is an io for a glimpse, then we don't care;
 644          *
 645          *     - if this not a glimpse (writepage or lock cancellation), then
 646          *       layout change cannot happen because a page or a lock
 647          *       already exist; and
 648          *
 649          *     - lock ordering (lock mutex nests within layout rw-semaphore)
 650          *       is obeyed in case of lock cancellation.
 651          */
 652         return LOV_2DISPATCH_MAYLOCK(cl2lov(obj), llo_io_init,
 653                                      io->ci_type != CIT_MISC, env, obj, io);
 654 }
 655
 656 /**
 657  * An implementation of cl_object_operations::clo_attr_get() method for lov
 658  * layer. For raid0 layout this collects and merges attributes of all
 659  * sub-objects.
 660  */
 661 static int lov_attr_get(const struct lu_env *env, struct cl_object *obj,
 662                         struct cl_attr *attr)
 663 {
 664         /* do not take lock, as this function is called under a
 665          * spin-lock. Layout is protected from changing by ongoing IO. */
 666         return LOV_2DISPATCH_NOLOCK(cl2lov(obj), llo_getattr, env, obj, attr);
 667 }
 668
 669 static int lov_attr_set(const struct lu_env *env, struct cl_object *obj,
 670                         const struct cl_attr *attr, unsigned valid)
 671 {
 672         /*
 673          * No dispatch is required here, as no layout implements this.
 674          */
 675         return 0;
 676 }
 677
 678 int lov_lock_init(const struct lu_env *env, struct cl_object *obj,
 679                   struct cl_lock *lock, const struct cl_io *io)
 680 {
 681         return LOV_2DISPATCH(cl2lov(obj), llo_lock_init, env, obj, lock, io);
 682 }
 683
 684 static const struct cl_object_operations lov_ops = {
 685         .coo_page_init = lov_page_init,
 686         .coo_lock_init = lov_lock_init,
 687         .coo_io_init   = lov_io_init,
 688         .coo_attr_get  = lov_attr_get,
 689         .coo_attr_set  = lov_attr_set,
 690         .coo_conf_set  = lov_conf_set
 691 };
 692
 693 static const struct lu_object_operations lov_lu_obj_ops = {
 694         .loo_object_init      = lov_object_init,
 695         .loo_object_delete    = lov_object_delete,
 696         .loo_object_release   = NULL,
 697         .loo_object_free      = lov_object_free,
 698         .loo_object_print     = lov_object_print,
 699         .loo_object_invariant = NULL
 700 };
 701
 702 struct lu_object *lov_object_alloc(const struct lu_env *env,
 703                                    const struct lu_object_header *unused,
 704                                    struct lu_device *dev)
 705 {
 706         struct lov_object *lov;
 707         struct lu_object  *obj;
 708
 709         ENTRY;
 710         OBD_SLAB_ALLOC_PTR_GFP(lov, lov_object_kmem, CFS_ALLOC_IO);
 711         if (lov != NULL) {
 712                 obj = lov2lu(lov);
 713                 lu_object_init(obj, NULL, dev);
 714                 lov->lo_cl.co_ops = &lov_ops;
 715                 lov->lo_type = -1; /* invalid, to catch uninitialized type */
 716                 /*
 717                  * object io operation vector (cl_object::co_iop) is installed
 718                  * later in lov_object_init(), as different vectors are used
 719                  * for object with different layouts.
 720                  */
 721                 obj->lo_ops = &lov_lu_obj_ops;
 722         } else
 723                 obj = NULL;
 724         RETURN(obj);
 725 }
 726
 727 struct lov_stripe_md *lov_lsm_addref(struct lov_object *lov)
 728 {
 729         struct lov_stripe_md *lsm = NULL;
 730
 731         cfs_down_read(&lov->lo_type_guard);
 732         switch (lov->lo_type) {
 733         case LLT_RAID0:
 734                 lsm = lsm_addref(lov->u.raid0.lo_lsm);
 735         case LLT_EMPTY:
 736                 break;
 737         default:
 738                 LBUG();
 739         }
 740         cfs_up_read(&lov->lo_type_guard);
 741         return lsm;
 742 }
 743
 744 void lov_lsm_decref(struct lov_object *lov, struct lov_stripe_md *lsm)
 745 {
 746         if (lsm == NULL)
 747                 return;
 748
 749         lov_free_memmd(&lsm);
 750         if (lov->lo_owner != NULL)
 751                 cfs_waitq_signal(&lov->lo_waitq);
 752 }
 753
 754 struct lov_stripe_md *lov_lsm_get(struct cl_object *clobj)
 755 {
 756         struct lu_object *luobj;
 757         struct lov_stripe_md *lsm = NULL;
 758
 759         if (clobj == NULL)
 760                 return NULL;
 761
 762         luobj = lu_object_locate(&cl_object_header(clobj)->coh_lu,
 763                                  &lov_device_type);
 764         if (luobj != NULL)
 765                 lsm = lov_lsm_addref(lu2lov(luobj));
 766         return lsm;
 767 }
 768 EXPORT_SYMBOL(lov_lsm_get);
 769
 770 void lov_lsm_put(struct cl_object *clobj, struct lov_stripe_md *lsm)
 771 {
 772         struct lu_object *luobj;
 773
 774         if (clobj == NULL || lsm == NULL)
 775                 return;
 776
 777         luobj = lu_object_locate(&cl_object_header(clobj)->coh_lu,
 778                                  &lov_device_type);
 779         LASSERT(luobj != NULL);
 780
 781         lov_lsm_decref(lu2lov(luobj), lsm);
 782 }
 783 EXPORT_SYMBOL(lov_lsm_put);
 784
 785 int lov_read_and_clear_async_rc(struct cl_object *clob)
 786 {
 787         struct lu_object *luobj;
 788         int rc = 0;
 789         ENTRY;
 790
 791         luobj = lu_object_locate(&cl_object_header(clob)->coh_lu,
 792                                  &lov_device_type);
 793         if (luobj != NULL) {
 794                 struct lov_object *lov = lu2lov(luobj);
 795
 796                 cfs_down_read(&lov->lo_type_guard);
 797                 switch (lov->lo_type) {
 798                 case LLT_RAID0: {
 799                         struct lov_stripe_md *lsm;
 800                         int i;
 801
 802                         lsm = lov->u.raid0.lo_lsm;
 803                         LASSERT(lsm != NULL);
 804                         for (i = 0; i < lsm->lsm_stripe_count; i++) {
 805                                 struct lov_oinfo *loi = lsm->lsm_oinfo[i];
 806                                 if (loi->loi_ar.ar_rc && !rc)
 807                                         rc = loi->loi_ar.ar_rc;
 808                                 loi->loi_ar.ar_rc = 0;
 809                         }
 810                 }
 811                 case LLT_EMPTY:
 812                         break;
 813                 default:
 814                         LBUG();
 815                 }
 816                 cfs_up_read(&lov->lo_type_guard);
 817         }
 818         RETURN(rc);
 819 }
 820 EXPORT_SYMBOL(lov_read_and_clear_async_rc);
 821
 822 /** @} lov */