lustre/osc/osc_page.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_page for OSC layer.
  37  *
  38  *   Author: Nikita Danilov <nikita.danilov@sun.com>
  39  */
  40
  41 #define DEBUG_SUBSYSTEM S_OSC
  42
  43 #include "osc_cl_internal.h"
  44
  45 /** \addtogroup osc
  46  *  @{
  47  */
  48
  49 /*
  50  * Comment out osc_page_protected because it may sleep inside the
  51  * the client_obd_list_lock.
  52  * client_obd_list_lock -> osc_ap_completion -> osc_completion ->
  53  *   -> osc_page_protected -> osc_page_is_dlocked -> osc_match_base
  54  *   -> ldlm_lock_match -> sptlrpc_import_check_ctx -> sleep.
  55  */
  56 #if 0
  57 static int osc_page_is_dlocked(const struct lu_env *env,
  58                                const struct osc_page *opg,
  59                                enum cl_lock_mode mode, int pending, int unref)
  60 {
  61         struct cl_page         *page;
  62         struct osc_object      *obj;
  63         struct osc_thread_info *info;
  64         struct ldlm_res_id     *resname;
  65         struct lustre_handle   *lockh;
  66         ldlm_policy_data_t     *policy;
  67         ldlm_mode_t             dlmmode;
  68         int                     flags;
  69
  70         cfs_might_sleep();
  71
  72         info = osc_env_info(env);
  73         resname = &info->oti_resname;
  74         policy = &info->oti_policy;
  75         lockh = &info->oti_handle;
  76         page = opg->ops_cl.cpl_page;
  77         obj = cl2osc(opg->ops_cl.cpl_obj);
  78
  79         flags = LDLM_FL_TEST_LOCK | LDLM_FL_BLOCK_GRANTED;
  80         if (pending)
  81                 flags |= LDLM_FL_CBPENDING;
  82
  83         dlmmode = osc_cl_lock2ldlm(mode) | LCK_PW;
  84         osc_lock_build_res(env, obj, resname);
  85         osc_index2policy(policy, page->cp_obj, page->cp_index, page->cp_index);
  86         return osc_match_base(osc_export(obj), resname, LDLM_EXTENT, policy,
  87                               dlmmode, &flags, NULL, lockh, unref);
  88 }
  89
  90 /**
  91  * Checks an invariant that a page in the cache is covered by a lock, as
  92  * needed.
  93  */
  94 static int osc_page_protected(const struct lu_env *env,
  95                               const struct osc_page *opg,
  96                               enum cl_lock_mode mode, int unref)
  97 {
  98         struct cl_object_header *hdr;
  99         struct cl_lock          *scan;
 100         struct cl_page          *page;
 101         struct cl_lock_descr    *descr;
 102         int result;
 103
 104         LINVRNT(!opg->ops_temp);
 105
 106         page = opg->ops_cl.cpl_page;
 107         if (page->cp_owner != NULL &&
 108             cl_io_top(page->cp_owner)->ci_lockreq == CILR_NEVER)
 109                 /*
 110                  * If IO is done without locks (liblustre, or lloop), lock is
 111                  * not required.
 112                  */
 113                 result = 1;
 114         else
 115                 /* otherwise check for a DLM lock */
 116         result = osc_page_is_dlocked(env, opg, mode, 1, unref);
 117         if (result == 0) {
 118                 /* maybe this page is a part of a lockless io? */
 119                 hdr = cl_object_header(opg->ops_cl.cpl_obj);
 120                 descr = &osc_env_info(env)->oti_descr;
 121                 descr->cld_mode = mode;
 122                 descr->cld_start = page->cp_index;
 123                 descr->cld_end   = page->cp_index;
 124                 cfs_spin_lock(&hdr->coh_lock_guard);
 125                 cfs_list_for_each_entry(scan, &hdr->coh_locks, cll_linkage) {
 126                         /*
 127                          * Lock-less sub-lock has to be either in HELD state
 128                          * (when io is actively going on), or in CACHED state,
 129                          * when top-lock is being unlocked:
 130                          * cl_io_unlock()->cl_unuse()->...->lov_lock_unuse().
 131                          */
 132                         if ((scan->cll_state == CLS_HELD ||
 133                              scan->cll_state == CLS_CACHED) &&
 134                             cl_lock_ext_match(&scan->cll_descr, descr)) {
 135                                 struct osc_lock *olck;
 136
 137                                 olck = osc_lock_at(scan);
 138                                 result = osc_lock_is_lockless(olck);
 139                                 break;
 140                         }
 141                 }
 142                 cfs_spin_unlock(&hdr->coh_lock_guard);
 143         }
 144         return result;
 145 }
 146 #else
 147 static int osc_page_protected(const struct lu_env *env,
 148                               const struct osc_page *opg,
 149                               enum cl_lock_mode mode, int unref)
 150 {
 151         return 1;
 152 }
 153 #endif
 154
 155 /*****************************************************************************
 156  *
 157  * Page operations.
 158  *
 159  */
 160 static void osc_page_fini(const struct lu_env *env,
 161                           struct cl_page_slice *slice)
 162 {
 163         struct osc_page *opg = cl2osc_page(slice);
 164         CDEBUG(D_TRACE, "%p\n", opg);
 165         OBD_SLAB_FREE_PTR(opg, osc_page_kmem);
 166 }
 167
 168 static void osc_page_transfer_get(struct osc_page *opg, const char *label)
 169 {
 170         struct cl_page *page = cl_page_top(opg->ops_cl.cpl_page);
 171
 172         LASSERT(!opg->ops_transfer_pinned);
 173         cl_page_get(page);
 174         lu_ref_add_atomic(&page->cp_reference, label, page);
 175         opg->ops_transfer_pinned = 1;
 176 }
 177
 178 static void osc_page_transfer_put(const struct lu_env *env,
 179                                   struct osc_page *opg)
 180 {
 181         struct cl_page *page = cl_page_top(opg->ops_cl.cpl_page);
 182
 183         if (opg->ops_transfer_pinned) {
 184                 lu_ref_del(&page->cp_reference, "transfer", page);
 185                 opg->ops_transfer_pinned = 0;
 186                 cl_page_put(env, page);
 187         }
 188 }
 189
 190 /**
 191  * This is called once for every page when it is submitted for a transfer
 192  * either opportunistic (osc_page_cache_add()), or immediate
 193  * (osc_page_submit()).
 194  */
 195 static void osc_page_transfer_add(const struct lu_env *env,
 196                                   struct osc_page *opg, enum cl_req_type crt)
 197 {
 198         struct osc_object *obj;
 199
 200         LINVRNT(cl_page_is_vmlocked(env, opg->ops_cl.cpl_page));
 201
 202         obj = cl2osc(opg->ops_cl.cpl_obj);
 203         cfs_spin_lock(&obj->oo_seatbelt);
 204         cfs_list_add(&opg->ops_inflight, &obj->oo_inflight[crt]);
 205         opg->ops_submitter = cfs_current();
 206         cfs_spin_unlock(&obj->oo_seatbelt);
 207 }
 208
 209 static int osc_page_cache_add(const struct lu_env *env,
 210                               const struct cl_page_slice *slice,
 211                               struct cl_io *unused)
 212 {
 213         struct osc_page   *opg = cl2osc_page(slice);
 214         struct osc_object *obj = cl2osc(opg->ops_cl.cpl_obj);
 215         int result;
 216         int brw_flags;
 217         int noquota = 0;
 218
 219         LINVRNT(osc_page_protected(env, opg, CLM_WRITE, 0));
 220         ENTRY;
 221
 222         /* Set the OBD_BRW_SRVLOCK before the page is queued. */
 223         brw_flags = opg->ops_srvlock ? OBD_BRW_SRVLOCK : 0;
 224         if (!client_is_remote(osc_export(obj)) &&
 225             cfs_capable(CFS_CAP_SYS_RESOURCE)) {
 226                 brw_flags |= OBD_BRW_NOQUOTA;
 227                 noquota = OBD_BRW_NOQUOTA;
 228         }
 229
 230         osc_page_transfer_get(opg, "transfer\0cache");
 231         result = osc_queue_async_io(env, osc_export(obj), NULL, obj->oo_oinfo,
 232                                     &opg->ops_oap, OBD_BRW_WRITE | noquota,
 233                                     0, 0, brw_flags, 0);
 234         if (result != 0)
 235                 osc_page_transfer_put(env, opg);
 236         else
 237                 osc_page_transfer_add(env, opg, CRT_WRITE);
 238         RETURN(result);
 239 }
 240
 241 void osc_index2policy(ldlm_policy_data_t *policy, const struct cl_object *obj,
 242                       pgoff_t start, pgoff_t end)
 243 {
 244         memset(policy, 0, sizeof *policy);
 245         policy->l_extent.start = cl_offset(obj, start);
 246         policy->l_extent.end   = cl_offset(obj, end + 1) - 1;
 247 }
 248
 249 static int osc_page_is_under_lock(const struct lu_env *env,
 250                                   const struct cl_page_slice *slice,
 251                                   struct cl_io *unused)
 252 {
 253         struct cl_lock *lock;
 254         int             result;
 255
 256         ENTRY;
 257         lock = cl_lock_at_page(env, slice->cpl_obj, slice->cpl_page,
 258                                NULL, 1, 0);
 259         if (lock != NULL) {
 260                 cl_lock_put(env, lock);
 261                 result = -EBUSY;
 262         } else
 263                 result = -ENODATA;
 264         RETURN(result);
 265 }
 266
 267 static int osc_page_fail(const struct lu_env *env,
 268                          const struct cl_page_slice *slice,
 269                          struct cl_io *unused)
 270 {
 271         /*
 272          * Cached read?
 273          */
 274         LBUG();
 275         return 0;
 276 }
 277
 278
 279 static const char *osc_list(cfs_list_t *head)
 280 {
 281         return cfs_list_empty(head) ? "-" : "+";
 282 }
 283
 284 static inline cfs_time_t osc_submit_duration(struct osc_page *opg)
 285 {
 286         if (opg->ops_submit_time == 0)
 287                 return 0;
 288
 289         return (cfs_time_current() - opg->ops_submit_time);
 290 }
 291
 292 static int osc_page_print(const struct lu_env *env,
 293                           const struct cl_page_slice *slice,
 294                           void *cookie, lu_printer_t printer)
 295 {
 296         struct osc_page       *opg = cl2osc_page(slice);
 297         struct osc_async_page *oap = &opg->ops_oap;
 298         struct osc_object     *obj = cl2osc(slice->cpl_obj);
 299         struct client_obd     *cli = &osc_export(obj)->exp_obd->u.cli;
 300         struct lov_oinfo      *loi = obj->oo_oinfo;
 301
 302         return (*printer)(env, cookie, LUSTRE_OSC_NAME"-page@%p: "
 303                           "1< %#x %d %u %s %s %s > "
 304                           "2< %llu %u %#x %#x | %p %p %p %p %p > "
 305                           "3< %s %p %d %lu %d > "
 306                           "4< %d %d %d %lu %s | %s %s %s %s > "
 307                           "5< %s %s %s %s | %d %s %s | %d %s %s>\n",
 308                           opg,
 309                           /* 1 */
 310                           oap->oap_magic, oap->oap_cmd,
 311                           oap->oap_interrupted,
 312                           osc_list(&oap->oap_pending_item),
 313                           osc_list(&oap->oap_urgent_item),
 314                           osc_list(&oap->oap_rpc_item),
 315                           /* 2 */
 316                           oap->oap_obj_off, oap->oap_page_off,
 317                           oap->oap_async_flags, oap->oap_brw_flags,
 318                           oap->oap_request,
 319                           oap->oap_cli, oap->oap_loi, oap->oap_caller_ops,
 320                           oap->oap_caller_data,
 321                           /* 3 */
 322                           osc_list(&opg->ops_inflight),
 323                           opg->ops_submitter, opg->ops_transfer_pinned,
 324                           osc_submit_duration(opg), opg->ops_srvlock,
 325                           /* 4 */
 326                           cli->cl_r_in_flight, cli->cl_w_in_flight,
 327                           cli->cl_max_rpcs_in_flight,
 328                           cli->cl_avail_grant,
 329                           osc_list(&cli->cl_cache_waiters),
 330                           osc_list(&cli->cl_loi_ready_list),
 331                           osc_list(&cli->cl_loi_hp_ready_list),
 332                           osc_list(&cli->cl_loi_write_list),
 333                           osc_list(&cli->cl_loi_read_list),
 334                           /* 5 */
 335                           osc_list(&loi->loi_ready_item),
 336                           osc_list(&loi->loi_hp_ready_item),
 337                           osc_list(&loi->loi_write_item),
 338                           osc_list(&loi->loi_read_item),
 339                           loi->loi_read_lop.lop_num_pending,
 340                           osc_list(&loi->loi_read_lop.lop_pending),
 341                           osc_list(&loi->loi_read_lop.lop_urgent),
 342                           loi->loi_write_lop.lop_num_pending,
 343                           osc_list(&loi->loi_write_lop.lop_pending),
 344                           osc_list(&loi->loi_write_lop.lop_urgent));
 345 }
 346
 347 static void osc_page_delete(const struct lu_env *env,
 348                             const struct cl_page_slice *slice)
 349 {
 350         struct osc_page       *opg = cl2osc_page(slice);
 351         struct osc_object     *obj = cl2osc(opg->ops_cl.cpl_obj);
 352         struct osc_async_page *oap = &opg->ops_oap;
 353         int rc;
 354
 355         LINVRNT(opg->ops_temp || osc_page_protected(env, opg, CLM_READ, 1));
 356
 357         ENTRY;
 358         CDEBUG(D_TRACE, "%p\n", opg);
 359         osc_page_transfer_put(env, opg);
 360         rc = osc_teardown_async_page(osc_export(obj), NULL, obj->oo_oinfo, oap);
 361         if (rc) {
 362                 CL_PAGE_DEBUG(D_ERROR, env, cl_page_top(slice->cpl_page),
 363                               "Trying to teardown failed: %d\n", rc);
 364                 LASSERT(0);
 365         }
 366         cfs_spin_lock(&obj->oo_seatbelt);
 367         cfs_list_del_init(&opg->ops_inflight);
 368         cfs_spin_unlock(&obj->oo_seatbelt);
 369         EXIT;
 370 }
 371
 372 void osc_page_clip(const struct lu_env *env, const struct cl_page_slice *slice,
 373                    int from, int to)
 374 {
 375         struct osc_page       *opg = cl2osc_page(slice);
 376         struct osc_async_page *oap = &opg->ops_oap;
 377
 378         LINVRNT(osc_page_protected(env, opg, CLM_READ, 0));
 379
 380         opg->ops_from = from;
 381         opg->ops_to   = to;
 382         cfs_spin_lock(&oap->oap_lock);
 383         oap->oap_async_flags |= ASYNC_COUNT_STABLE;
 384         cfs_spin_unlock(&oap->oap_lock);
 385 }
 386
 387 static int osc_page_cancel(const struct lu_env *env,
 388                            const struct cl_page_slice *slice)
 389 {
 390         struct osc_page *opg       = cl2osc_page(slice);
 391         struct osc_async_page *oap = &opg->ops_oap;
 392         int rc = 0;
 393
 394         LINVRNT(osc_page_protected(env, opg, CLM_READ, 0));
 395
 396         client_obd_list_lock(&oap->oap_cli->cl_loi_list_lock);
 397         /* Check if the transferring against this page
 398          * is completed, or not even queued. */
 399         if (opg->ops_transfer_pinned)
 400                 /* FIXME: may not be interrupted.. */
 401                 rc = osc_oap_interrupted(env, oap);
 402         LASSERT(ergo(rc == 0, opg->ops_transfer_pinned == 0));
 403         client_obd_list_unlock(&oap->oap_cli->cl_loi_list_lock);
 404         return rc;
 405 }
 406
 407 static const struct cl_page_operations osc_page_ops = {
 408         .cpo_fini          = osc_page_fini,
 409         .cpo_print         = osc_page_print,
 410         .cpo_delete        = osc_page_delete,
 411         .cpo_is_under_lock = osc_page_is_under_lock,
 412         .io = {
 413                 [CRT_READ] = {
 414                         .cpo_cache_add = osc_page_fail
 415                 },
 416                 [CRT_WRITE] = {
 417                         .cpo_cache_add = osc_page_cache_add
 418                 }
 419         },
 420         .cpo_clip           = osc_page_clip,
 421         .cpo_cancel         = osc_page_cancel
 422 };
 423
 424 static int osc_make_ready(const struct lu_env *env, void *data, int cmd)
 425 {
 426         struct osc_page *opg  = data;
 427         struct cl_page  *page = cl_page_top(opg->ops_cl.cpl_page);
 428         int result;
 429
 430         LASSERT(cmd == OBD_BRW_WRITE); /* no cached reads */
 431         LINVRNT(osc_page_protected(env, opg, CLM_WRITE, 1));
 432
 433         ENTRY;
 434         result = cl_page_make_ready(env, page, CRT_WRITE);
 435         if (result == 0)
 436                 opg->ops_submit_time = cfs_time_current();
 437         RETURN(result);
 438 }
 439
 440 static int osc_refresh_count(const struct lu_env *env, void *data, int cmd)
 441 {
 442         struct cl_page   *page;
 443         struct osc_page  *osc = data;
 444         struct cl_object *obj;
 445         struct cl_attr   *attr = &osc_env_info(env)->oti_attr;
 446
 447         int result;
 448         loff_t kms;
 449
 450         LINVRNT(osc_page_protected(env, osc, CLM_READ, 1));
 451
 452         /* readpage queues with _COUNT_STABLE, shouldn't get here. */
 453         LASSERT(!(cmd & OBD_BRW_READ));
 454         LASSERT(osc != NULL);
 455         page = osc->ops_cl.cpl_page;
 456         obj = osc->ops_cl.cpl_obj;
 457
 458         cl_object_attr_lock(obj);
 459         result = cl_object_attr_get(env, obj, attr);
 460         cl_object_attr_unlock(obj);
 461         if (result < 0)
 462                 return result;
 463         kms = attr->cat_kms;
 464         if (cl_offset(obj, page->cp_index) >= kms)
 465                 /* catch race with truncate */
 466                 return 0;
 467         else if (cl_offset(obj, page->cp_index + 1) > kms)
 468                 /* catch sub-page write at end of file */
 469                 return kms % CFS_PAGE_SIZE;
 470         else
 471                 return CFS_PAGE_SIZE;
 472 }
 473
 474 static int osc_completion(const struct lu_env *env,
 475                           void *data, int cmd, struct obdo *oa, int rc)
 476 {
 477         struct osc_page       *opg  = data;
 478         struct osc_async_page *oap  = &opg->ops_oap;
 479         struct cl_page        *page = cl_page_top(opg->ops_cl.cpl_page);
 480         struct osc_object     *obj  = cl2osc(opg->ops_cl.cpl_obj);
 481         enum cl_req_type crt;
 482
 483         LINVRNT(osc_page_protected(env, opg, CLM_READ, 1));
 484         LINVRNT(cl_page_is_vmlocked(env, page));
 485
 486         ENTRY;
 487
 488         cmd &= ~OBD_BRW_NOQUOTA;
 489         LASSERT(equi(page->cp_state == CPS_PAGEIN,  cmd == OBD_BRW_READ));
 490         LASSERT(equi(page->cp_state == CPS_PAGEOUT, cmd == OBD_BRW_WRITE));
 491         LASSERT(opg->ops_transfer_pinned);
 492
 493         /*
 494          * page->cp_req can be NULL if io submission failed before
 495          * cl_req was allocated.
 496          */
 497         if (page->cp_req != NULL)
 498                 cl_req_page_done(env, page);
 499         LASSERT(page->cp_req == NULL);
 500
 501         /* As the transfer for this page is being done, clear the flags */
 502         cfs_spin_lock(&oap->oap_lock);
 503         oap->oap_async_flags = 0;
 504         cfs_spin_unlock(&oap->oap_lock);
 505
 506         crt = cmd == OBD_BRW_READ ? CRT_READ : CRT_WRITE;
 507         /* Clear opg->ops_transfer_pinned before VM lock is released. */
 508         opg->ops_transfer_pinned = 0;
 509
 510         cfs_spin_lock(&obj->oo_seatbelt);
 511         LASSERT(opg->ops_submitter != NULL);
 512         LASSERT(!cfs_list_empty(&opg->ops_inflight));
 513         cfs_list_del_init(&opg->ops_inflight);
 514         cfs_spin_unlock(&obj->oo_seatbelt);
 515
 516         opg->ops_submit_time = 0;
 517
 518         cl_page_completion(env, page, crt, rc);
 519
 520         /* statistic */
 521         if (rc == 0 && oap->oap_brw_flags & OBD_BRW_SRVLOCK) {
 522                 struct lu_device *ld    = opg->ops_cl.cpl_obj->co_lu.lo_dev;
 523                 struct osc_stats *stats = &lu2osc_dev(ld)->od_stats;
 524                 int bytes = opg->ops_to - opg->ops_from;
 525
 526                 if (crt == CRT_READ)
 527                         stats->os_lockless_reads += bytes;
 528                 else
 529                         stats->os_lockless_writes += bytes;
 530         }
 531
 532         /*
 533          * This has to be the last operation with the page, as locks are
 534          * released in cl_page_completion() and nothing except for the
 535          * reference counter protects page from concurrent reclaim.
 536          */
 537         lu_ref_del(&page->cp_reference, "transfer", page);
 538         /*
 539          * As page->cp_obj is pinned by a reference from page->cp_req, it is
 540          * safe to call cl_page_put() without risking object destruction in a
 541          * non-blocking context.
 542          */
 543         cl_page_put(env, page);
 544         RETURN(0);
 545 }
 546
 547 const static struct obd_async_page_ops osc_async_page_ops = {
 548         .ap_make_ready    = osc_make_ready,
 549         .ap_refresh_count = osc_refresh_count,
 550         .ap_completion    = osc_completion
 551 };
 552
 553 struct cl_page *osc_page_init(const struct lu_env *env,
 554                               struct cl_object *obj,
 555                               struct cl_page *page, cfs_page_t *vmpage)
 556 {
 557         struct osc_object *osc = cl2osc(obj);
 558         struct osc_page   *opg;
 559         int result;
 560
 561         OBD_SLAB_ALLOC_PTR_GFP(opg, osc_page_kmem, CFS_ALLOC_IO);
 562         if (opg != NULL) {
 563                 void *oap = &opg->ops_oap;
 564
 565                 opg->ops_from = 0;
 566                 opg->ops_to   = CFS_PAGE_SIZE;
 567
 568                 result = osc_prep_async_page(osc_export(osc),
 569                                              NULL, osc->oo_oinfo, vmpage,
 570                                              cl_offset(obj, page->cp_index),
 571                                              &osc_async_page_ops,
 572                                              opg, (void **)&oap, 1, NULL);
 573                 if (result == 0) {
 574                         struct osc_io *oio = osc_env_io(env);
 575                         opg->ops_srvlock = osc_io_srvlock(oio);
 576                         cl_page_slice_add(page, &opg->ops_cl, obj,
 577                                           &osc_page_ops);
 578                 }
 579                 /*
 580                  * Cannot assert osc_page_protected() here as read-ahead
 581                  * creates temporary pages outside of a lock.
 582                  */
 583 #ifdef INVARIANT_CHECK
 584                 opg->ops_temp = !osc_page_protected(env, opg, CLM_READ, 1);
 585 #endif
 586                 CFS_INIT_LIST_HEAD(&opg->ops_inflight);
 587         } else
 588                 result = -ENOMEM;
 589         return ERR_PTR(result);
 590 }
 591
 592 /**
 593  * Helper function called by osc_io_submit() for every page in an immediate
 594  * transfer (i.e., transferred synchronously).
 595  */
 596 void osc_io_submit_page(const struct lu_env *env,
 597                         struct osc_io *oio, struct osc_page *opg,
 598                         enum cl_req_type crt)
 599 {
 600         struct osc_async_page *oap = &opg->ops_oap;
 601         struct client_obd     *cli = oap->oap_cli;
 602         int flags = 0;
 603
 604         LINVRNT(osc_page_protected(env, opg,
 605                                    crt == CRT_WRITE ? CLM_WRITE : CLM_READ, 1));
 606
 607         oap->oap_page_off   = opg->ops_from;
 608         oap->oap_count      = opg->ops_to - opg->ops_from;
 609         /* Give a hint to OST that requests are coming from kswapd - bug19529 */
 610         if (libcfs_memory_pressure_get())
 611                 oap->oap_brw_flags |= OBD_BRW_MEMALLOC;
 612         oap->oap_brw_flags |= OBD_BRW_SYNC;
 613         if (osc_io_srvlock(oio))
 614                 oap->oap_brw_flags |= OBD_BRW_SRVLOCK;
 615
 616         oap->oap_cmd = crt == CRT_WRITE ? OBD_BRW_WRITE : OBD_BRW_READ;
 617         if (!client_is_remote(osc_export(cl2osc(opg->ops_cl.cpl_obj))) &&
 618             cfs_capable(CFS_CAP_SYS_RESOURCE)) {
 619                 oap->oap_brw_flags |= OBD_BRW_NOQUOTA;
 620                 oap->oap_cmd |= OBD_BRW_NOQUOTA;
 621         }
 622
 623         if (oap->oap_cmd & OBD_BRW_READ)
 624                 flags = ASYNC_COUNT_STABLE;
 625         else if (!(oap->oap_brw_page.flag & OBD_BRW_FROM_GRANT))
 626                 osc_enter_cache_try(env, cli, oap->oap_loi, oap, 1);
 627
 628         cfs_spin_lock(&oap->oap_lock);
 629         oap->oap_async_flags |= OSC_FLAGS | flags;
 630         cfs_spin_unlock(&oap->oap_lock);
 631
 632         osc_oap_to_pending(oap);
 633         osc_page_transfer_get(opg, "transfer\0imm");
 634         osc_page_transfer_add(env, opg, crt);
 635 }
 636
 637 /** @} osc */