lustre/target/update_trans.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.gnu.org/licenses/gpl-2.0.html
  19  *
  20  * GPL HEADER END
  21  */
  22 /*
  23  * Copyright (c) 2015, 2016, Intel Corporation.
  24  */
  25 /*
  26  * lustre/target/update_trans.c
  27  *
  28  * This file implements the update distribute transaction API.
  29  *
  30  * To manage the cross-MDT operation (distribute operation) transaction,
  31  * the transaction will also be separated two layers on MD stack, top
  32  * transaction and sub transaction.
  33  *
  34  * During the distribute operation, top transaction is created in the LOD
  35  * layer, and represent the operation. Sub transaction is created by
  36  * each OSD or OSP. Top transaction start/stop will trigger all of its sub
  37  * transaction start/stop. Top transaction (the whole operation) is committed
  38  * only all of its sub transaction are committed.
  39  *
  40  * there are three kinds of transactions
  41  * 1. local transaction: All updates are in a single local OSD.
  42  * 2. Remote transaction: All Updates are only in the remote OSD,
  43  *    i.e. locally all updates are in OSP.
  44  * 3. Mixed transaction: Updates are both in local OSD and remote
  45  *    OSD.
  46  *
  47  * Author: Di Wang <di.wang@intel.com>
  48  */
  49
  50 #define DEBUG_SUBSYSTEM S_CLASS
  51
  52 #include <linux/kthread.h>
  53 #include <lu_target.h>
  54 #include <lustre_log.h>
  55 #include <lustre_update.h>
  56 #include <obd.h>
  57 #include <obd_class.h>
  58 #include <tgt_internal.h>
  59
  60 #include <tgt_internal.h>
  61 /**
  62  * Dump top mulitple thandle
  63  *
  64  * Dump top multiple thandle and all of its sub thandle to the debug log.
  65  *
  66  * \param[in]mask       debug mask
  67  * \param[in]top_th     top_thandle to be dumped
  68  */
  69 static void top_multiple_thandle_dump(struct top_multiple_thandle *tmt,
  70                                       __u32 mask)
  71 {
  72         struct sub_thandle      *st;
  73
  74         LASSERT(tmt->tmt_magic == TOP_THANDLE_MAGIC);
  75         CDEBUG(mask, "%s tmt %p refcount %d committed %d result %d batchid %llu\n",
  76                tmt->tmt_master_sub_dt ?
  77                tmt->tmt_master_sub_dt->dd_lu_dev.ld_obd->obd_name :
  78                "NULL",
  79                tmt, atomic_read(&tmt->tmt_refcount), tmt->tmt_committed,
  80                tmt->tmt_result, tmt->tmt_batchid);
  81
  82         list_for_each_entry(st, &tmt->tmt_sub_thandle_list, st_sub_list) {
  83                 struct sub_thandle_cookie *stc;
  84
  85                 CDEBUG(mask, "st %p obd %s committed %d stopped %d sub_th %p\n",
  86                        st, st->st_dt->dd_lu_dev.ld_obd->obd_name,
  87                        st->st_committed, st->st_stopped, st->st_sub_th);
  88
  89                 list_for_each_entry(stc, &st->st_cookie_list, stc_list) {
  90                         CDEBUG(mask, " cookie "DFID".%u\n",
  91                                PFID(&stc->stc_cookie.lgc_lgl.lgl_oi.oi_fid),
  92                                stc->stc_cookie.lgc_index);
  93                 }
  94         }
  95 }
  96
  97 /**
  98  * Declare write update to sub device
  99  *
 100  * Declare Write updates llog records to the sub device during distribute
 101  * transaction.
 102  *
 103  * \param[in] env       execution environment
 104  * \param[in] record    update records being written
 105  * \param[in] sub_th    sub transaction handle
 106  * \param[in] record_size total update record size
 107  *
 108  * \retval              0 if writing succeeds
 109  * \retval              negative errno if writing fails
 110  */
 111 static int sub_declare_updates_write(const struct lu_env *env,
 112                                      struct llog_update_record *record,
 113                                      struct thandle *sub_th, size_t record_size)
 114 {
 115         struct llog_ctxt        *ctxt;
 116         struct dt_device        *dt = sub_th->th_dev;
 117         int                     left = record_size;
 118         int rc;
 119
 120         /* If ctxt is NULL, it means not need to write update,
 121          * for example if the the OSP is used to connect to OST */
 122         ctxt = llog_get_context(dt->dd_lu_dev.ld_obd,
 123                                 LLOG_UPDATELOG_ORIG_CTXT);
 124
 125         /* Not ready to record updates yet. */
 126         if (ctxt == NULL || ctxt->loc_handle == NULL) {
 127                 llog_ctxt_put(ctxt);
 128                 return 0;
 129         }
 130
 131         rc = llog_declare_add(env, ctxt->loc_handle,
 132                               &record->lur_hdr, sub_th);
 133         if (rc < 0)
 134                 GOTO(out_put, rc);
 135
 136         while (left > ctxt->loc_chunk_size) {
 137                 rc = llog_declare_add(env, ctxt->loc_handle,
 138                                       &record->lur_hdr, sub_th);
 139                 if (rc < 0)
 140                         GOTO(out_put, rc);
 141
 142                 left -= ctxt->loc_chunk_size;
 143         }
 144
 145 out_put:
 146         llog_ctxt_put(ctxt);
 147
 148         return rc;
 149 }
 150
 151 /**
 152  * write update to sub device
 153  *
 154  * Write llog update record to the sub device during distribute
 155  * transaction. If it succeeds, llog cookie of the record will be
 156  * returned by @cookie.
 157  *
 158  * \param[in] env       execution environment
 159  * \param[in] record    update records being written
 160  * \param[in] sub_th    sub transaction handle
 161  * \param[out] cookie   llog cookie of the update record.
 162  *
 163  * \retval              1 if writing succeeds
 164  * \retval              negative errno if writing fails
 165  */
 166 static int sub_updates_write(const struct lu_env *env,
 167                              struct llog_update_record *record,
 168                              struct sub_thandle *sub_th)
 169 {
 170         struct dt_device *dt = sub_th->st_dt;
 171         struct llog_ctxt *ctxt;
 172         struct llog_update_record *lur = NULL;
 173         __u32 update_count = 0;
 174         __u32 param_count = 0;
 175         __u32 last_update_count = 0;
 176         __u32 last_param_count = 0;
 177         char *start;
 178         char *cur;
 179         char *next;
 180         struct sub_thandle_cookie *stc;
 181         size_t reclen;
 182         bool eof = false;
 183         int rc;
 184         ENTRY;
 185
 186         ctxt = llog_get_context(dt->dd_lu_dev.ld_obd,
 187                                 LLOG_UPDATELOG_ORIG_CTXT);
 188         /* If ctxt == NULL, then it means updates on OST (only happens
 189          * during migration), and we do not track those updates for now */
 190         /* If ctxt->loc_handle == NULL, then it does not need to record
 191          * update, usually happens in error handler path */
 192         if (ctxt == NULL || ctxt->loc_handle == NULL) {
 193                 llog_ctxt_put(ctxt);
 194                 RETURN(0);
 195         }
 196
 197         /* Since the cross-MDT updates will includes both local
 198          * and remote updates, the update ops count must > 1 */
 199         LASSERT(record->lur_update_rec.ur_update_count > 1);
 200         LASSERTF(record->lur_hdr.lrh_len == llog_update_record_size(record),
 201                  "lrh_len %u record_size %zu\n", record->lur_hdr.lrh_len,
 202                  llog_update_record_size(record));
 203
 204         if (likely(record->lur_hdr.lrh_len <= ctxt->loc_chunk_size)) {
 205                 OBD_ALLOC_PTR(stc);
 206                 if (stc == NULL)
 207                         GOTO(llog_put, rc = -ENOMEM);
 208                 INIT_LIST_HEAD(&stc->stc_list);
 209
 210                 rc = llog_add(env, ctxt->loc_handle, &record->lur_hdr,
 211                               &stc->stc_cookie, sub_th->st_sub_th);
 212
 213                 CDEBUG(D_INFO, "%s: Add update log "DFID".%u: rc = %d\n",
 214                        dt->dd_lu_dev.ld_obd->obd_name,
 215                        PFID(&stc->stc_cookie.lgc_lgl.lgl_oi.oi_fid),
 216                        stc->stc_cookie.lgc_index, rc);
 217
 218                 if (rc > 0) {
 219                         list_add(&stc->stc_list, &sub_th->st_cookie_list);
 220                         rc = 0;
 221                 } else {
 222                         OBD_FREE_PTR(stc);
 223                 }
 224
 225                 GOTO(llog_put, rc);
 226         }
 227
 228         /* Split the records into chunk_size update record */
 229         OBD_ALLOC_LARGE(lur, ctxt->loc_chunk_size);
 230         if (lur == NULL)
 231                 GOTO(llog_put, rc = -ENOMEM);
 232
 233         memcpy(lur, &record->lur_hdr, sizeof(record->lur_hdr));
 234         lur->lur_update_rec.ur_update_count = 0;
 235         lur->lur_update_rec.ur_param_count = 0;
 236         start = (char *)&record->lur_update_rec.ur_ops;
 237         cur = next = start;
 238         do {
 239                 if (update_count < record->lur_update_rec.ur_update_count)
 240                         next = (char *)update_op_next_op(
 241                                                 (struct update_op *)cur);
 242                 else if (param_count < record->lur_update_rec.ur_param_count)
 243                         next = (char *)update_param_next_param(
 244                                                 (struct update_param *)cur);
 245                 else
 246                         eof = true;
 247
 248                 /*
 249                  * If its size > llog chunk_size, then write current chunk to
 250                  * the update llog, NB the padding should >= LLOG_MIN_REC_SIZE.
 251                  *
 252                  * So check padding length is either >= LLOG_MIN_REC_SIZE or is
 253                  * 0 (record length just matches the chunk size).
 254                  */
 255                 reclen = __llog_update_record_size(
 256                                 __update_records_size(next - start));
 257                 if ((reclen + LLOG_MIN_REC_SIZE <= ctxt->loc_chunk_size ||
 258                      reclen == ctxt->loc_chunk_size) &&
 259                     !eof) {
 260                         cur = next;
 261
 262                         if (update_count <
 263                             record->lur_update_rec.ur_update_count)
 264                                 update_count++;
 265                         else if (param_count <
 266                                  record->lur_update_rec.ur_param_count)
 267                                 param_count++;
 268                         continue;
 269                 }
 270
 271                 lur->lur_update_rec.ur_update_count = update_count -
 272                                                       last_update_count;
 273                 lur->lur_update_rec.ur_param_count = param_count -
 274                                                      last_param_count;
 275                 memcpy(&lur->lur_update_rec.ur_ops, start, cur - start);
 276                 lur->lur_hdr.lrh_len = llog_update_record_size(lur);
 277
 278                 LASSERT(lur->lur_hdr.lrh_len ==
 279                          __llog_update_record_size(
 280                                 __update_records_size(cur - start)));
 281                 LASSERT(lur->lur_hdr.lrh_len <= ctxt->loc_chunk_size);
 282
 283                 update_records_dump(&lur->lur_update_rec, D_INFO, true);
 284
 285                 OBD_ALLOC_PTR(stc);
 286                 if (stc == NULL)
 287                         GOTO(llog_put, rc = -ENOMEM);
 288                 INIT_LIST_HEAD(&stc->stc_list);
 289
 290                 rc = llog_add(env, ctxt->loc_handle, &lur->lur_hdr,
 291                               &stc->stc_cookie, sub_th->st_sub_th);
 292
 293                 CDEBUG(D_INFO, "%s: Add update log "DFID".%u: rc = %d\n",
 294                         dt->dd_lu_dev.ld_obd->obd_name,
 295                         PFID(&stc->stc_cookie.lgc_lgl.lgl_oi.oi_fid),
 296                         stc->stc_cookie.lgc_index, rc);
 297
 298                 if (rc > 0) {
 299                         list_add(&stc->stc_list, &sub_th->st_cookie_list);
 300                         rc = 0;
 301                 } else {
 302                         OBD_FREE_PTR(stc);
 303                         GOTO(llog_put, rc);
 304                 }
 305
 306                 last_update_count = update_count;
 307                 last_param_count = param_count;
 308                 start = cur;
 309                 lur->lur_update_rec.ur_update_count = 0;
 310                 lur->lur_update_rec.ur_param_count = 0;
 311                 lur->lur_update_rec.ur_flags |= UPDATE_RECORD_CONTINUE;
 312         } while (!eof);
 313
 314 llog_put:
 315         if (lur != NULL)
 316                 OBD_FREE_LARGE(lur, ctxt->loc_chunk_size);
 317         llog_ctxt_put(ctxt);
 318
 319         RETURN(rc);
 320 }
 321
 322 /**
 323  * Prepare the update records.
 324  *
 325  * Merge params and ops into the update records, then initializing
 326  * the update buffer.
 327  *
 328  * During transaction execution phase, parameters and update ops
 329  * are collected in two different buffers (see lod_updates_pack()),
 330  * during transaction stop, it needs to be merged in one buffer,
 331  * so it will be written in the update log.
 332  *
 333  * \param[in] env       execution environment
 334  * \param[in] tmt       top_multiple_thandle for distribute txn
 335  *
 336  * \retval              0 if merging succeeds.
 337  * \retval              negaitive errno if merging fails.
 338  */
 339 static int prepare_writing_updates(const struct lu_env *env,
 340                                    struct top_multiple_thandle *tmt)
 341 {
 342         struct thandle_update_records   *tur = tmt->tmt_update_records;
 343         struct llog_update_record       *lur;
 344         struct update_params *params;
 345         size_t params_size;
 346         size_t update_size;
 347
 348         if (tur == NULL || tur->tur_update_records == NULL ||
 349             tur->tur_update_params == NULL)
 350                 return 0;
 351
 352         lur = tur->tur_update_records;
 353         /* Extends the update records buffer if needed */
 354         params_size = update_params_size(tur->tur_update_params,
 355                                          tur->tur_update_param_count);
 356         LASSERT(lur->lur_update_rec.ur_param_count == 0);
 357         update_size = llog_update_record_size(lur);
 358         if (cfs_size_round(update_size + params_size) >
 359             tur->tur_update_records_buf_size) {
 360                 int rc;
 361
 362                 rc = tur_update_records_extend(tur,
 363                         cfs_size_round(update_size + params_size));
 364                 if (rc < 0)
 365                         return rc;
 366
 367                 lur = tur->tur_update_records;
 368         }
 369
 370         params = update_records_get_params(&lur->lur_update_rec);
 371         memcpy(params, tur->tur_update_params, params_size);
 372
 373         lur->lur_update_rec.ur_param_count = tur->tur_update_param_count;
 374         lur->lur_update_rec.ur_batchid = tmt->tmt_batchid;
 375         /* Init update record header */
 376         lur->lur_hdr.lrh_len = llog_update_record_size(lur);
 377         lur->lur_hdr.lrh_type = UPDATE_REC;
 378
 379         /* Dump updates for debugging purpose */
 380         update_records_dump(&lur->lur_update_rec, D_INFO, true);
 381
 382         return 0;
 383 }
 384
 385 static inline int
 386 distribute_txn_commit_thread_running(struct lu_target *lut)
 387 {
 388         return lut->lut_tdtd_commit_thread.t_flags & SVC_RUNNING;
 389 }
 390
 391 static inline int
 392 distribute_txn_commit_thread_stopped(struct lu_target *lut)
 393 {
 394         return lut->lut_tdtd_commit_thread.t_flags & SVC_STOPPED;
 395 }
 396
 397 /**
 398  * Top thandle commit callback
 399  *
 400  * This callback will be called when all of sub transactions are committed.
 401  *
 402  * \param[in] th        top thandle to be committed.
 403  */
 404 static void top_trans_committed_cb(struct top_multiple_thandle *tmt)
 405 {
 406         struct lu_target *lut;
 407         ENTRY;
 408
 409         LASSERT(atomic_read(&tmt->tmt_refcount) > 0);
 410
 411         top_multiple_thandle_dump(tmt, D_HA);
 412         tmt->tmt_committed = 1;
 413         lut = dt2lu_dev(tmt->tmt_master_sub_dt)->ld_site->ls_tgt;
 414         if (distribute_txn_commit_thread_running(lut))
 415                 wake_up(&lut->lut_tdtd->tdtd_commit_thread_waitq);
 416         RETURN_EXIT;
 417 }
 418
 419 struct sub_thandle *lookup_sub_thandle(struct top_multiple_thandle *tmt,
 420                                        struct dt_device *dt_dev)
 421 {
 422         struct sub_thandle *st;
 423
 424         list_for_each_entry(st, &tmt->tmt_sub_thandle_list, st_sub_list) {
 425                 if (st->st_dt == dt_dev)
 426                         return st;
 427         }
 428         return NULL;
 429 }
 430 EXPORT_SYMBOL(lookup_sub_thandle);
 431
 432 struct sub_thandle *create_sub_thandle(struct top_multiple_thandle *tmt,
 433                                        struct dt_device *dt_dev)
 434 {
 435         struct sub_thandle *st;
 436
 437         OBD_ALLOC_PTR(st);
 438         if (st == NULL)
 439                 RETURN(ERR_PTR(-ENOMEM));
 440
 441         INIT_LIST_HEAD(&st->st_sub_list);
 442         INIT_LIST_HEAD(&st->st_cookie_list);
 443         st->st_dt = dt_dev;
 444
 445         list_add(&st->st_sub_list, &tmt->tmt_sub_thandle_list);
 446         return st;
 447 }
 448
 449 static void sub_trans_commit_cb_internal(struct top_multiple_thandle *tmt,
 450                                          struct thandle *sub_th, int err)
 451 {
 452         struct sub_thandle      *st;
 453         bool                    all_committed = true;
 454
 455         /* Check if all sub thandles are committed */
 456         spin_lock(&tmt->tmt_sub_lock);
 457         list_for_each_entry(st, &tmt->tmt_sub_thandle_list, st_sub_list) {
 458                 if (st->st_sub_th == sub_th) {
 459                         st->st_committed = 1;
 460                         st->st_result = err;
 461                 }
 462                 if (!st->st_committed)
 463                         all_committed = false;
 464         }
 465         spin_unlock(&tmt->tmt_sub_lock);
 466
 467         if (tmt->tmt_result == 0)
 468                 tmt->tmt_result = err;
 469
 470         if (all_committed)
 471                 top_trans_committed_cb(tmt);
 472
 473         top_multiple_thandle_dump(tmt, D_INFO);
 474         top_multiple_thandle_put(tmt);
 475         RETURN_EXIT;
 476 }
 477
 478 /**
 479  * sub thandle commit callback
 480  *
 481  * Mark the sub thandle to be committed and if all sub thandle are committed
 482  * notify the top thandle.
 483  *
 484  * \param[in] env       execution environment
 485  * \param[in] sub_th    sub thandle being committed
 486  * \param[in] cb        commit callback
 487  * \param[in] err       trans result
 488  */
 489 static void sub_trans_commit_cb(struct lu_env *env,
 490                                 struct thandle *sub_th,
 491                                 struct dt_txn_commit_cb *cb, int err)
 492 {
 493         struct top_multiple_thandle *tmt = cb->dcb_data;
 494
 495         sub_trans_commit_cb_internal(tmt, sub_th, err);
 496 }
 497
 498 static void sub_thandle_register_commit_cb(struct sub_thandle *st,
 499                                     struct top_multiple_thandle *tmt)
 500 {
 501         LASSERT(st->st_sub_th != NULL);
 502         top_multiple_thandle_get(tmt);
 503         st->st_commit_dcb.dcb_func = sub_trans_commit_cb;
 504         st->st_commit_dcb.dcb_data = tmt;
 505         INIT_LIST_HEAD(&st->st_commit_dcb.dcb_linkage);
 506         dt_trans_cb_add(st->st_sub_th, &st->st_commit_dcb);
 507 }
 508
 509 /**
 510  * Sub thandle stop call back
 511  *
 512  * After sub thandle is stopped, it will call this callback to notify
 513  * the top thandle.
 514  *
 515  * \param[in] th        sub thandle to be stopped
 516  * \param[in] rc        result of sub trans
 517  */
 518 static void sub_trans_stop_cb(struct lu_env *env,
 519                               struct thandle *sub_th,
 520                               struct dt_txn_commit_cb *cb, int err)
 521 {
 522         struct sub_thandle              *st;
 523         struct top_multiple_thandle     *tmt = cb->dcb_data;
 524         ENTRY;
 525
 526         list_for_each_entry(st, &tmt->tmt_sub_thandle_list, st_sub_list) {
 527                 if (st->st_stopped)
 528                         continue;
 529
 530                 if (st->st_dt == sub_th->th_dev) {
 531                         st->st_stopped = 1;
 532                         st->st_result = err;
 533                         break;
 534                 }
 535         }
 536
 537         wake_up(&tmt->tmt_stop_waitq);
 538         RETURN_EXIT;
 539 }
 540
 541 static void sub_thandle_register_stop_cb(struct sub_thandle *st,
 542                                          struct top_multiple_thandle *tmt)
 543 {
 544         st->st_stop_dcb.dcb_func = sub_trans_stop_cb;
 545         st->st_stop_dcb.dcb_data = tmt;
 546         st->st_stop_dcb.dcb_flags = DCB_TRANS_STOP;
 547         INIT_LIST_HEAD(&st->st_stop_dcb.dcb_linkage);
 548         dt_trans_cb_add(st->st_sub_th, &st->st_stop_dcb);
 549 }
 550
 551 /**
 552  * Create sub thandle
 553  *
 554  * Create transaction handle for sub_thandle
 555  *
 556  * \param[in] env       execution environment
 557  * \param[in] th        top thandle
 558  * \param[in] st        sub_thandle
 559  *
 560  * \retval              0 if creation succeeds.
 561  * \retval              negative errno if creation fails.
 562  */
 563 int sub_thandle_trans_create(const struct lu_env *env,
 564                              struct top_thandle *top_th,
 565                              struct sub_thandle *st)
 566 {
 567         struct thandle *sub_th;
 568
 569         sub_th = dt_trans_create(env, st->st_dt);
 570         if (IS_ERR(sub_th))
 571                 return PTR_ERR(sub_th);
 572
 573         sub_th->th_top = &top_th->tt_super;
 574         st->st_sub_th = sub_th;
 575
 576         sub_th->th_wait_submit = 1;
 577         sub_thandle_register_stop_cb(st, top_th->tt_multiple_thandle);
 578         return 0;
 579 }
 580
 581 /**
 582  * Create the top transaction.
 583  *
 584  * Create the top transaction on the master device. It will create a top
 585  * thandle and a sub thandle on the master device.
 586  *
 587  * \param[in] env               execution environment
 588  * \param[in] master_dev        master_dev the top thandle will be created
 589  *
 590  * \retval                      pointer to the created thandle.
 591  * \retval                      ERR_PTR(errno) if creation failed.
 592  */
 593 struct thandle *
 594 top_trans_create(const struct lu_env *env, struct dt_device *master_dev)
 595 {
 596         struct top_thandle      *top_th;
 597         struct thandle          *child_th;
 598
 599         OBD_ALLOC_GFP(top_th, sizeof(*top_th), __GFP_IO);
 600         if (top_th == NULL)
 601                 return ERR_PTR(-ENOMEM);
 602
 603         top_th->tt_super.th_top = &top_th->tt_super;
 604
 605         if (master_dev != NULL) {
 606                 child_th = dt_trans_create(env, master_dev);
 607                 if (IS_ERR(child_th)) {
 608                         OBD_FREE_PTR(top_th);
 609                         return child_th;
 610                 }
 611
 612                 child_th->th_top = &top_th->tt_super;
 613                 child_th->th_wait_submit = 1;
 614                 top_th->tt_master_sub_thandle = child_th;
 615
 616                 top_th->tt_super.th_tags |= child_th->th_tags;
 617         }
 618         return &top_th->tt_super;
 619 }
 620 EXPORT_SYMBOL(top_trans_create);
 621
 622 /**
 623  * Declare write update transaction
 624  *
 625  * Check if there are updates being recorded in this transaction,
 626  * it will write the record into the disk.
 627  *
 628  * \param[in] env       execution environment
 629  * \param[in] tmt       top multiple transaction handle
 630  *
 631  * \retval              0 if writing succeeds
 632  * \retval              negative errno if writing fails
 633  */
 634 static int declare_updates_write(const struct lu_env *env,
 635                                  struct top_multiple_thandle *tmt)
 636 {
 637         struct llog_update_record *record;
 638         struct sub_thandle *st;
 639         int rc = 0;
 640
 641         record = tmt->tmt_update_records->tur_update_records;
 642         /* Declare update write for all other target */
 643         list_for_each_entry(st, &tmt->tmt_sub_thandle_list, st_sub_list) {
 644                 if (st->st_sub_th == NULL)
 645                         continue;
 646
 647                 rc = sub_declare_updates_write(env, record, st->st_sub_th,
 648                                                tmt->tmt_record_size);
 649                 if (rc < 0)
 650                         break;
 651         }
 652
 653         return rc;
 654 }
 655
 656 /**
 657  * Assign batchid to the distribute transaction.
 658  *
 659  * Assign batchid to the distribute transaction
 660  *
 661  * \param[in] tmt       distribute transaction
 662  */
 663 static void distribute_txn_assign_batchid(struct top_multiple_thandle *new)
 664 {
 665         struct target_distribute_txn_data *tdtd;
 666         struct dt_device *dt = new->tmt_master_sub_dt;
 667         struct sub_thandle *st;
 668
 669         LASSERT(dt != NULL);
 670         tdtd = dt2lu_dev(dt)->ld_site->ls_tgt->lut_tdtd;
 671         spin_lock(&tdtd->tdtd_batchid_lock);
 672         new->tmt_batchid = tdtd->tdtd_batchid++;
 673         list_add_tail(&new->tmt_commit_list, &tdtd->tdtd_list);
 674         spin_unlock(&tdtd->tdtd_batchid_lock);
 675         list_for_each_entry(st, &new->tmt_sub_thandle_list, st_sub_list) {
 676                 if (st->st_sub_th != NULL)
 677                         sub_thandle_register_commit_cb(st, new);
 678         }
 679         top_multiple_thandle_get(new);
 680         top_multiple_thandle_dump(new, D_INFO);
 681 }
 682
 683 /**
 684  * Insert distribute transaction to the distribute txn list.
 685  *
 686  * Insert distribute transaction to the distribute txn list.
 687  *
 688  * \param[in] new       the distribute txn to be inserted.
 689  */
 690 void distribute_txn_insert_by_batchid(struct top_multiple_thandle *new)
 691 {
 692         struct dt_device *dt = new->tmt_master_sub_dt;
 693         struct top_multiple_thandle *tmt;
 694         struct target_distribute_txn_data *tdtd;
 695         struct sub_thandle *st;
 696         bool    at_head = false;
 697
 698         LASSERT(dt != NULL);
 699         tdtd = dt2lu_dev(dt)->ld_site->ls_tgt->lut_tdtd;
 700
 701         spin_lock(&tdtd->tdtd_batchid_lock);
 702         list_for_each_entry_reverse(tmt, &tdtd->tdtd_list, tmt_commit_list) {
 703                 if (new->tmt_batchid > tmt->tmt_batchid) {
 704                         list_add(&new->tmt_commit_list, &tmt->tmt_commit_list);
 705                         break;
 706                 }
 707         }
 708         if (list_empty(&new->tmt_commit_list)) {
 709                 at_head = true;
 710                 list_add(&new->tmt_commit_list, &tdtd->tdtd_list);
 711         }
 712         spin_unlock(&tdtd->tdtd_batchid_lock);
 713
 714         list_for_each_entry(st, &new->tmt_sub_thandle_list, st_sub_list) {
 715                 if (st->st_sub_th != NULL)
 716                         sub_thandle_register_commit_cb(st, new);
 717         }
 718
 719         top_multiple_thandle_get(new);
 720         top_multiple_thandle_dump(new, D_INFO);
 721         if (new->tmt_committed && at_head)
 722                 wake_up(&tdtd->tdtd_commit_thread_waitq);
 723 }
 724
 725 /**
 726  * Prepare cross-MDT operation.
 727  *
 728  * Create the update record buffer to record updates for cross-MDT operation,
 729  * add master sub transaction to tt_sub_trans_list, and declare the update
 730  * writes.
 731  *
 732  * During updates packing, all of parameters will be packed in
 733  * tur_update_params, and updates will be packed in tur_update_records.
 734  * Then in transaction stop, parameters and updates will be merged
 735  * into one updates buffer.
 736  *
 737  * And also master thandle will be added to the sub_th list, so it will be
 738  * easy to track the commit status.
 739  *
 740  * \param[in] env       execution environment
 741  * \param[in] th        top transaction handle
 742  *
 743  * \retval              0 if preparation succeeds.
 744  * \retval              negative errno if preparation fails.
 745  */
 746 static int prepare_multiple_node_trans(const struct lu_env *env,
 747                                        struct top_multiple_thandle *tmt)
 748 {
 749         struct thandle_update_records   *tur;
 750         int                             rc;
 751         ENTRY;
 752
 753         if (tmt->tmt_update_records == NULL) {
 754                 tur = &update_env_info(env)->uti_tur;
 755                 rc = check_and_prepare_update_record(env, tur);
 756                 if (rc < 0)
 757                         RETURN(rc);
 758
 759                 tmt->tmt_update_records = tur;
 760                 distribute_txn_assign_batchid(tmt);
 761         }
 762
 763         rc = declare_updates_write(env, tmt);
 764
 765         RETURN(rc);
 766 }
 767
 768 /**
 769  * start the top transaction.
 770  *
 771  * Start all of its sub transactions, then start master sub transaction.
 772  *
 773  * \param[in] env               execution environment
 774  * \param[in] master_dev        master_dev the top thandle will be start
 775  * \param[in] th                top thandle
 776  *
 777  * \retval                      0 if transaction start succeeds.
 778  * \retval                      negative errno if start fails.
 779  */
 780 int top_trans_start(const struct lu_env *env, struct dt_device *master_dev,
 781                     struct thandle *th)
 782 {
 783         struct top_thandle      *top_th = container_of(th, struct top_thandle,
 784                                                        tt_super);
 785         struct sub_thandle              *st;
 786         struct top_multiple_thandle     *tmt = top_th->tt_multiple_thandle;
 787         int                             rc = 0;
 788         ENTRY;
 789
 790         if (tmt == NULL) {
 791                 if (th->th_sync)
 792                         top_th->tt_master_sub_thandle->th_sync = th->th_sync;
 793                 if (th->th_local)
 794                         top_th->tt_master_sub_thandle->th_local = th->th_local;
 795                 top_th->tt_master_sub_thandle->th_tags = th->th_tags;
 796                 rc = dt_trans_start(env, top_th->tt_master_sub_thandle->th_dev,
 797                                     top_th->tt_master_sub_thandle);
 798                 RETURN(rc);
 799         }
 800
 801         tmt = top_th->tt_multiple_thandle;
 802         rc = prepare_multiple_node_trans(env, tmt);
 803         if (rc < 0)
 804                 RETURN(rc);
 805
 806         list_for_each_entry(st, &tmt->tmt_sub_thandle_list, st_sub_list) {
 807                 if (st->st_sub_th == NULL)
 808                         continue;
 809                 if (th->th_sync)
 810                         st->st_sub_th->th_sync = th->th_sync;
 811                 if (th->th_local)
 812                         st->st_sub_th->th_local = th->th_local;
 813                 st->st_sub_th->th_tags = th->th_tags;
 814                 rc = dt_trans_start(env, st->st_sub_th->th_dev,
 815                                     st->st_sub_th);
 816                 if (rc != 0)
 817                         GOTO(out, rc);
 818
 819                 LASSERT(st->st_started == 0);
 820                 st->st_started = 1;
 821         }
 822 out:
 823         th->th_result = rc;
 824         RETURN(rc);
 825 }
 826 EXPORT_SYMBOL(top_trans_start);
 827
 828 /**
 829  * Check whether we need write updates record
 830  *
 831  * Check if the updates for the top_thandle needs to be writen
 832  * to all targets. Only if the transaction succeeds and the updates
 833  * number > 2, it will write the updates,
 834  *
 835  * \params [in] top_th  top thandle.
 836  *
 837  * \retval              true if it needs to write updates
 838  * \retval              false if it does not need to write updates
 839  **/
 840 static bool top_check_write_updates(struct top_thandle *top_th)
 841 {
 842         struct top_multiple_thandle     *tmt;
 843         struct thandle_update_records   *tur;
 844
 845         /* Do not write updates to records if the transaction fails */
 846         if (top_th->tt_super.th_result != 0)
 847                 return false;
 848
 849         tmt = top_th->tt_multiple_thandle;
 850         if (tmt == NULL)
 851                 return false;
 852
 853         tur = tmt->tmt_update_records;
 854         if (tur == NULL)
 855                 return false;
 856
 857         /* Hmm, false update records, since the cross-MDT operation
 858          * should includes both local and remote updates, so the
 859          * updates count should >= 2 */
 860         if (tur->tur_update_records == NULL ||
 861             tur->tur_update_records->lur_update_rec.ur_update_count <= 1)
 862                 return false;
 863
 864         return true;
 865 }
 866
 867 /**
 868  * Check if top transaction is stopped
 869  *
 870  * Check if top transaction is stopped, only if all sub transaction
 871  * is stopped, then the top transaction is stopped.
 872  *
 873  * \param [in] top_th   top thandle
 874  *
 875  * \retval              true if the top transaction is stopped.
 876  * \retval              false if the top transaction is not stopped.
 877  */
 878 static bool top_trans_is_stopped(struct top_thandle *top_th)
 879 {
 880         struct top_multiple_thandle     *tmt;
 881         struct sub_thandle              *st;
 882         bool                    all_stopped = true;
 883
 884         tmt = top_th->tt_multiple_thandle;
 885         list_for_each_entry(st, &tmt->tmt_sub_thandle_list, st_sub_list) {
 886                 if (!st->st_stopped && st->st_sub_th != NULL) {
 887                         all_stopped = false;
 888                         break;
 889                 }
 890
 891                 if (st->st_result != 0 &&
 892                     top_th->tt_super.th_result == 0)
 893                         top_th->tt_super.th_result = st->st_result;
 894         }
 895
 896         return all_stopped;
 897 }
 898
 899 /**
 900  * Wait result of top transaction
 901  *
 902  * Wait until all sub transaction get its result.
 903  *
 904  * \param [in] top_th   top thandle.
 905  *
 906  * \retval              the result of top thandle.
 907  */
 908 static int top_trans_wait_result(struct top_thandle *top_th)
 909 {
 910         struct l_wait_info      lwi = {0};
 911
 912         l_wait_event(top_th->tt_multiple_thandle->tmt_stop_waitq,
 913                      top_trans_is_stopped(top_th), &lwi);
 914
 915         RETURN(top_th->tt_super.th_result);
 916 }
 917
 918 /**
 919  * Stop the top transaction.
 920  *
 921  * Stop the transaction on the master device first, then stop transactions
 922  * on other sub devices.
 923  *
 924  * \param[in] env               execution environment
 925  * \param[in] master_dev        master_dev the top thandle will be created
 926  * \param[in] th                top thandle
 927  *
 928  * \retval                      0 if stop transaction succeeds.
 929  * \retval                      negative errno if stop transaction fails.
 930  */
 931 int top_trans_stop(const struct lu_env *env, struct dt_device *master_dev,
 932                    struct thandle *th)
 933 {
 934         struct top_thandle      *top_th = container_of(th, struct top_thandle,
 935                                                        tt_super);
 936         struct sub_thandle              *st;
 937         struct sub_thandle              *master_st;
 938         struct top_multiple_thandle     *tmt;
 939         struct thandle_update_records   *tur;
 940         bool                            write_updates = false;
 941         int                     rc = 0;
 942         ENTRY;
 943
 944         if (likely(top_th->tt_multiple_thandle == NULL)) {
 945                 LASSERT(master_dev != NULL);
 946
 947                 if (th->th_sync)
 948                         top_th->tt_master_sub_thandle->th_sync = th->th_sync;
 949                 if (th->th_local)
 950                         top_th->tt_master_sub_thandle->th_local = th->th_local;
 951                 top_th->tt_master_sub_thandle->th_tags = th->th_tags;
 952                 rc = dt_trans_stop(env, master_dev,
 953                                    top_th->tt_master_sub_thandle);
 954                 OBD_FREE_PTR(top_th);
 955                 RETURN(rc);
 956         }
 957
 958         tmt = top_th->tt_multiple_thandle;
 959         tur = tmt->tmt_update_records;
 960
 961         /* Note: we need stop the master thandle first, then the stop
 962          * callback will fill the master transno in the update logs,
 963          * then these update logs will be sent to other MDTs */
 964         /* get the master sub thandle */
 965         master_st = lookup_sub_thandle(tmt, tmt->tmt_master_sub_dt);
 966         write_updates = top_check_write_updates(top_th);
 967
 968         /* Step 1: write the updates log on Master MDT */
 969         if (master_st != NULL && master_st->st_sub_th != NULL &&
 970             write_updates) {
 971                 struct llog_update_record *lur;
 972
 973                 /* Merge the parameters and updates into one buffer */
 974                 rc = prepare_writing_updates(env, tmt);
 975                 if (rc < 0) {
 976                         CERROR("%s: cannot prepare updates: rc = %d\n",
 977                                master_dev->dd_lu_dev.ld_obd->obd_name, rc);
 978                         th->th_result = rc;
 979                         write_updates = false;
 980                         GOTO(stop_master_trans, rc);
 981                 }
 982
 983                 lur = tur->tur_update_records;
 984                 /* Write updates to the master MDT */
 985                 rc = sub_updates_write(env, lur, master_st);
 986
 987                 /* Cleanup the common parameters in the update records,
 988                  * master transno callback might add more parameters.
 989                  * and we need merge the update records again in the
 990                  * following */
 991                 if (tur->tur_update_params != NULL)
 992                         lur->lur_update_rec.ur_param_count = 0;
 993
 994                 if (rc < 0) {
 995                         CERROR("%s: write updates failed: rc = %d\n",
 996                                master_dev->dd_lu_dev.ld_obd->obd_name, rc);
 997                         th->th_result = rc;
 998                         write_updates = false;
 999                         GOTO(stop_master_trans, rc);
1000                 }
1001         }
1002
1003 stop_master_trans:
1004         /* Step 2: Stop the transaction on the master MDT, and fill the
1005          * master transno in the update logs to other MDT. */
1006         if (master_st != NULL && master_st->st_sub_th != NULL) {
1007                 if (th->th_local)
1008                         master_st->st_sub_th->th_local = th->th_local;
1009                 if (th->th_sync)
1010                         master_st->st_sub_th->th_sync = th->th_sync;
1011                 master_st->st_sub_th->th_tags = th->th_tags;
1012                 master_st->st_sub_th->th_result = th->th_result;
1013                 rc = dt_trans_stop(env, master_st->st_dt, master_st->st_sub_th);
1014                 /* If it does not write_updates, then we call submit callback
1015                  * here, otherwise callback is done through
1016                  * osd(osp)_trans_commit_cb() */
1017                 if (!master_st->st_started &&
1018                     !list_empty(&tmt->tmt_commit_list))
1019                         sub_trans_commit_cb_internal(tmt,
1020                                                 master_st->st_sub_th, rc);
1021                 if (rc < 0) {
1022                         th->th_result = rc;
1023                         GOTO(stop_other_trans, rc);
1024                 } else if (tur != NULL && tur->tur_update_records != NULL) {
1025                         struct llog_update_record *lur;
1026
1027                         lur = tur->tur_update_records;
1028                         if (lur->lur_update_rec.ur_master_transno == 0)
1029                                 /* Update master transno after master stop
1030                                  * callback */
1031                                 lur->lur_update_rec.ur_master_transno =
1032                                                 tgt_th_info(env)->tti_transno;
1033                 }
1034         }
1035
1036         /* Step 3: write updates to other MDTs */
1037         if (write_updates) {
1038                 struct llog_update_record *lur;
1039
1040                 /* Stop callback of master will add more updates and also update
1041                  * master transno, so merge the parameters and updates into one
1042                  * buffer again */
1043                 rc = prepare_writing_updates(env, tmt);
1044                 if (rc < 0) {
1045                         CERROR("%s: prepare updates failed: rc = %d\n",
1046                                master_dev->dd_lu_dev.ld_obd->obd_name, rc);
1047                         th->th_result = rc;
1048                         GOTO(stop_other_trans, rc);
1049                 }
1050                 lur = tur->tur_update_records;
1051                 list_for_each_entry(st, &tmt->tmt_sub_thandle_list,
1052                                     st_sub_list) {
1053                         if (st->st_sub_th == NULL || st == master_st ||
1054                             st->st_sub_th->th_result < 0)
1055                                 continue;
1056
1057                         rc = sub_updates_write(env, lur, st);
1058                         if (rc < 0) {
1059                                 th->th_result = rc;
1060                                 break;
1061                         }
1062                 }
1063         }
1064
1065 stop_other_trans:
1066         /* Step 4: Stop the transaction on other MDTs */
1067         list_for_each_entry(st, &tmt->tmt_sub_thandle_list, st_sub_list) {
1068                 if (st == master_st || st->st_sub_th == NULL)
1069                         continue;
1070
1071                 if (th->th_sync)
1072                         st->st_sub_th->th_sync = th->th_sync;
1073                 if (th->th_local)
1074                         st->st_sub_th->th_local = th->th_local;
1075                 st->st_sub_th->th_tags = th->th_tags;
1076                 st->st_sub_th->th_result = th->th_result;
1077                 rc = dt_trans_stop(env, st->st_sub_th->th_dev,
1078                                    st->st_sub_th);
1079                 if (unlikely(rc < 0 && th->th_result == 0))
1080                         th->th_result = rc;
1081         }
1082
1083         rc = top_trans_wait_result(top_th);
1084
1085         tmt->tmt_result = rc;
1086
1087         /* Balance for the refcount in top_trans_create, Note: if it is NOT
1088          * multiple node transaction, the top transaction will be destroyed. */
1089         top_multiple_thandle_put(tmt);
1090         OBD_FREE_PTR(top_th);
1091         RETURN(rc);
1092 }
1093 EXPORT_SYMBOL(top_trans_stop);
1094
1095 /**
1096  * Create top_multiple_thandle for top_thandle
1097  *
1098  * Create top_mutilple_thandle to manage the mutiple node transaction
1099  * for top_thandle, and it also needs to add master sub thandle to the
1100  * sub trans list now.
1101  *
1102  * \param[in] env       execution environment
1103  * \param[in] top_th    the top thandle
1104  *
1105  * \retval      0 if creation succeeds
1106  * \retval      negative errno if creation fails
1107  */
1108 int top_trans_create_tmt(const struct lu_env *env,
1109                          struct top_thandle *top_th)
1110 {
1111         struct top_multiple_thandle *tmt;
1112
1113         OBD_ALLOC_PTR(tmt);
1114         if (tmt == NULL)
1115                 return -ENOMEM;
1116
1117         tmt->tmt_magic = TOP_THANDLE_MAGIC;
1118         INIT_LIST_HEAD(&tmt->tmt_sub_thandle_list);
1119         INIT_LIST_HEAD(&tmt->tmt_commit_list);
1120         atomic_set(&tmt->tmt_refcount, 1);
1121         spin_lock_init(&tmt->tmt_sub_lock);
1122         init_waitqueue_head(&tmt->tmt_stop_waitq);
1123
1124         top_th->tt_multiple_thandle = tmt;
1125
1126         return 0;
1127 }
1128
1129 static struct sub_thandle *
1130 create_sub_thandle_with_thandle(struct top_thandle *top_th,
1131                                 struct thandle *sub_th)
1132 {
1133         struct sub_thandle *st;
1134
1135         /* create and init sub th to the top trans list */
1136         st = create_sub_thandle(top_th->tt_multiple_thandle,
1137                                 sub_th->th_dev);
1138         if (IS_ERR(st))
1139                 return st;
1140
1141         st->st_sub_th = sub_th;
1142
1143         sub_th->th_top = &top_th->tt_super;
1144         sub_thandle_register_stop_cb(st, top_th->tt_multiple_thandle);
1145         return st;
1146 }
1147
1148 /**
1149  * Get sub thandle.
1150  *
1151  * Get sub thandle from the top thandle according to the sub dt_device.
1152  *
1153  * \param[in] env       execution environment
1154  * \param[in] th        thandle on the top layer.
1155  * \param[in] sub_dt    sub dt_device used to get sub transaction
1156  *
1157  * \retval              thandle of sub transaction if succeed
1158  * \retval              PTR_ERR(errno) if failed
1159  */
1160 struct thandle *thandle_get_sub_by_dt(const struct lu_env *env,
1161                                       struct thandle *th,
1162                                       struct dt_device *sub_dt)
1163 {
1164         struct sub_thandle      *st = NULL;
1165         struct sub_thandle      *master_st = NULL;
1166         struct top_thandle      *top_th;
1167         struct thandle          *sub_th = NULL;
1168         int                     rc = 0;
1169         ENTRY;
1170
1171         top_th = container_of(th, struct top_thandle, tt_super);
1172
1173         if (likely(sub_dt == top_th->tt_master_sub_thandle->th_dev))
1174                 RETURN(top_th->tt_master_sub_thandle);
1175
1176         if (top_th->tt_multiple_thandle != NULL) {
1177                 st = lookup_sub_thandle(top_th->tt_multiple_thandle, sub_dt);
1178                 if (st != NULL)
1179                         RETURN(st->st_sub_th);
1180         }
1181
1182         sub_th = dt_trans_create(env, sub_dt);
1183         if (IS_ERR(sub_th))
1184                 RETURN(sub_th);
1185
1186         /* Create top_multiple_thandle if necessary */
1187         if (top_th->tt_multiple_thandle == NULL) {
1188                 struct top_multiple_thandle *tmt;
1189
1190                 rc = top_trans_create_tmt(env, top_th);
1191                 if (rc < 0)
1192                         GOTO(stop_trans, rc);
1193
1194                 tmt = top_th->tt_multiple_thandle;
1195
1196                 /* Add master sub th to the top trans list */
1197                 tmt->tmt_master_sub_dt =
1198                         top_th->tt_master_sub_thandle->th_dev;
1199                 master_st = create_sub_thandle_with_thandle(top_th,
1200                                         top_th->tt_master_sub_thandle);
1201                 if (IS_ERR(master_st)) {
1202                         rc = PTR_ERR(master_st);
1203                         master_st = NULL;
1204                         GOTO(stop_trans, rc);
1205                 }
1206         }
1207
1208         /* create and init sub th to the top trans list */
1209         st = create_sub_thandle_with_thandle(top_th, sub_th);
1210         if (IS_ERR(st)) {
1211                 rc = PTR_ERR(st);
1212                 st = NULL;
1213                 GOTO(stop_trans, rc);
1214         }
1215         st->st_sub_th->th_wait_submit = 1;
1216 stop_trans:
1217         if (rc < 0) {
1218                 if (master_st != NULL) {
1219                         list_del(&master_st->st_sub_list);
1220                         OBD_FREE_PTR(master_st);
1221                 }
1222                 sub_th->th_result = rc;
1223                 dt_trans_stop(env, sub_dt, sub_th);
1224                 sub_th = ERR_PTR(rc);
1225         }
1226
1227         RETURN(sub_th);
1228 }
1229 EXPORT_SYMBOL(thandle_get_sub_by_dt);
1230
1231 /**
1232  * Top multiple thandle destroy
1233  *
1234  * Destroy multiple thandle and all its sub thandle.
1235  *
1236  * \param[in] tmt       top_multiple_thandle to be destroyed.
1237  */
1238 void top_multiple_thandle_destroy(struct top_multiple_thandle *tmt)
1239 {
1240         struct sub_thandle *st;
1241         struct sub_thandle *tmp;
1242
1243         LASSERT(tmt->tmt_magic == TOP_THANDLE_MAGIC);
1244         list_for_each_entry_safe(st, tmp, &tmt->tmt_sub_thandle_list,
1245                                  st_sub_list) {
1246                 struct sub_thandle_cookie *stc;
1247                 struct sub_thandle_cookie *tmp;
1248
1249                 list_del(&st->st_sub_list);
1250                 list_for_each_entry_safe(stc, tmp, &st->st_cookie_list,
1251                                          stc_list) {
1252                         list_del(&stc->stc_list);
1253                         OBD_FREE_PTR(stc);
1254                 }
1255                 OBD_FREE_PTR(st);
1256         }
1257         OBD_FREE_PTR(tmt);
1258 }
1259 EXPORT_SYMBOL(top_multiple_thandle_destroy);
1260
1261 /**
1262  * Cancel the update log on MDTs
1263  *
1264  * Cancel the update log on MDTs then destroy the thandle.
1265  *
1266  * \param[in] env       execution environment
1267  * \param[in] tmt       the top multiple thandle whose updates records
1268  *                      will be cancelled.
1269  *
1270  * \retval              0 if cancellation succeeds.
1271  * \retval              negative errno if cancellation fails.
1272  */
1273 static int distribute_txn_cancel_records(const struct lu_env *env,
1274                                          struct top_multiple_thandle *tmt)
1275 {
1276         struct sub_thandle *st;
1277         ENTRY;
1278
1279         top_multiple_thandle_dump(tmt, D_INFO);
1280         /* Cancel update logs on other MDTs */
1281         list_for_each_entry(st, &tmt->tmt_sub_thandle_list, st_sub_list) {
1282                 struct llog_ctxt        *ctxt;
1283                 struct obd_device       *obd;
1284                 struct llog_cookie      *cookie;
1285                 struct sub_thandle_cookie *stc;
1286                 int rc;
1287
1288                 obd = st->st_dt->dd_lu_dev.ld_obd;
1289                 ctxt = llog_get_context(obd, LLOG_UPDATELOG_ORIG_CTXT);
1290                 if (ctxt == NULL)
1291                         continue;
1292                 list_for_each_entry(stc, &st->st_cookie_list, stc_list) {
1293                         cookie = &stc->stc_cookie;
1294                         if (fid_is_zero(&cookie->lgc_lgl.lgl_oi.oi_fid))
1295                                 continue;
1296
1297                         rc = llog_cat_cancel_records(env, ctxt->loc_handle, 1,
1298                                                      cookie);
1299                         CDEBUG(D_HA, "%s: batchid %llu cancel update log "
1300                                DFID".%u: rc = %d\n", obd->obd_name,
1301                                tmt->tmt_batchid,
1302                                PFID(&cookie->lgc_lgl.lgl_oi.oi_fid),
1303                                cookie->lgc_index, rc);
1304                 }
1305
1306                 llog_ctxt_put(ctxt);
1307         }
1308
1309         RETURN(0);
1310 }
1311
1312 /**
1313  * Check if there are committed transaction
1314  *
1315  * Check if there are committed transaction in the distribute transaction
1316  * list, then cancel the update records for those committed transaction.
1317  * Because the distribute transaction in the list are sorted by batchid,
1318  * and cancellation will be done by batchid order, so we only check the first
1319  * the transaction(with lowest batchid) in the list.
1320  *
1321  * \param[in] lod       lod device where cancel thread is
1322  *
1323  * \retval              true if it is ready
1324  * \retval              false if it is not ready
1325  */
1326 static bool tdtd_ready_for_cancel_log(struct target_distribute_txn_data *tdtd)
1327 {
1328         struct top_multiple_thandle     *tmt = NULL;
1329         struct obd_device               *obd = tdtd->tdtd_lut->lut_obd;
1330         bool    ready = false;
1331
1332         spin_lock(&tdtd->tdtd_batchid_lock);
1333         if (!list_empty(&tdtd->tdtd_list)) {
1334                 tmt = list_entry(tdtd->tdtd_list.next,
1335                                  struct top_multiple_thandle, tmt_commit_list);
1336                 if (tmt->tmt_committed &&
1337                     (!obd->obd_recovering || (obd->obd_recovering &&
1338                     tmt->tmt_batchid <= tdtd->tdtd_committed_batchid)))
1339                         ready = true;
1340         }
1341         spin_unlock(&tdtd->tdtd_batchid_lock);
1342
1343         return ready;
1344 }
1345
1346 struct distribute_txn_bid_data {
1347         struct dt_txn_commit_cb  dtbd_cb;
1348         struct target_distribute_txn_data      *dtbd_tdtd;
1349         __u64                    dtbd_batchid;
1350 };
1351
1352 /**
1353  * callback of updating commit batchid
1354  *
1355  * Updating commit batchid then wake up the commit thread to cancel the
1356  * records.
1357  *
1358  * \param[in]env        execution environment
1359  * \param[in]th         thandle to updating commit batchid
1360  * \param[in]cb         commit callback
1361  * \param[in]err        result of thandle
1362  */
1363 static void distribute_txn_batchid_cb(struct lu_env *env,
1364                                       struct thandle *th,
1365                                       struct dt_txn_commit_cb *cb,
1366                                       int err)
1367 {
1368         struct distribute_txn_bid_data          *dtbd = NULL;
1369         struct target_distribute_txn_data       *tdtd;
1370
1371         dtbd = container_of0(cb, struct distribute_txn_bid_data, dtbd_cb);
1372         tdtd = dtbd->dtbd_tdtd;
1373
1374         CDEBUG(D_HA, "%s: %llu batchid updated\n",
1375               tdtd->tdtd_lut->lut_obd->obd_name, dtbd->dtbd_batchid);
1376         spin_lock(&tdtd->tdtd_batchid_lock);
1377         if (dtbd->dtbd_batchid > tdtd->tdtd_committed_batchid &&
1378             !tdtd->tdtd_lut->lut_obd->obd_no_transno)
1379                 tdtd->tdtd_committed_batchid = dtbd->dtbd_batchid;
1380         spin_unlock(&tdtd->tdtd_batchid_lock);
1381         atomic_dec(&tdtd->tdtd_refcount);
1382         wake_up(&tdtd->tdtd_commit_thread_waitq);
1383
1384         OBD_FREE_PTR(dtbd);
1385 }
1386
1387 /**
1388  * Update the commit batchid in disk
1389  *
1390  * Update commit batchid in the disk, after this is committed, it can start
1391  * to cancel the update records.
1392  *
1393  * \param[in] env       execution environment
1394  * \param[in] tdtd      distribute transaction structure
1395  * \param[in] batchid   commit batchid to be updated
1396  *
1397  * \retval              0 if update succeeds.
1398  * \retval              negative errno if update fails.
1399  */
1400 static int
1401 distribute_txn_commit_batchid_update(const struct lu_env *env,
1402                               struct target_distribute_txn_data *tdtd,
1403                               __u64 batchid)
1404 {
1405         struct distribute_txn_bid_data  *dtbd = NULL;
1406         struct thandle          *th;
1407         struct lu_buf            buf;
1408         __u64                    tmp;
1409         __u64                    off;
1410         int                      rc;
1411         ENTRY;
1412
1413         OBD_ALLOC_PTR(dtbd);
1414         if (dtbd == NULL)
1415                 RETURN(-ENOMEM);
1416         dtbd->dtbd_batchid = batchid;
1417         dtbd->dtbd_tdtd = tdtd;
1418         dtbd->dtbd_cb.dcb_func = distribute_txn_batchid_cb;
1419         atomic_inc(&tdtd->tdtd_refcount);
1420
1421         th = dt_trans_create(env, tdtd->tdtd_lut->lut_bottom);
1422         if (IS_ERR(th)) {
1423                 OBD_FREE_PTR(dtbd);
1424                 RETURN(PTR_ERR(th));
1425         }
1426
1427         tmp = cpu_to_le64(batchid);
1428         buf.lb_buf = &tmp;
1429         buf.lb_len = sizeof(tmp);
1430         off = 0;
1431
1432         rc = dt_declare_record_write(env, tdtd->tdtd_batchid_obj, &buf, off,
1433                                      th);
1434         if (rc < 0)
1435                 GOTO(stop, rc);
1436
1437         rc = dt_trans_start_local(env, tdtd->tdtd_lut->lut_bottom, th);
1438         if (rc < 0)
1439                 GOTO(stop, rc);
1440
1441         rc = dt_trans_cb_add(th, &dtbd->dtbd_cb);
1442         if (rc < 0)
1443                 GOTO(stop, rc);
1444
1445         rc = dt_record_write(env, tdtd->tdtd_batchid_obj, &buf,
1446                              &off, th);
1447
1448         CDEBUG(D_INFO, "%s: update batchid %llu: rc = %d\n",
1449                tdtd->tdtd_lut->lut_obd->obd_name, batchid, rc);
1450
1451 stop:
1452         dt_trans_stop(env, tdtd->tdtd_lut->lut_bottom, th);
1453         if (rc < 0)
1454                 OBD_FREE_PTR(dtbd);
1455         RETURN(rc);
1456 }
1457
1458 /**
1459  * Init commit batchid for distribute transaction.
1460  *
1461  * Initialize the batchid object and get commit batchid from the object.
1462  *
1463  * \param[in] env       execution environment
1464  * \param[in] tdtd      distribute transaction whose batchid is initialized.
1465  *
1466  * \retval              0 if initialization succeeds.
1467  * \retval              negative errno if initialization fails.
1468  **/
1469 static int
1470 distribute_txn_commit_batchid_init(const struct lu_env *env,
1471                                    struct target_distribute_txn_data *tdtd)
1472 {
1473         struct tgt_thread_info  *tti = tgt_th_info(env);
1474         struct lu_target        *lut = tdtd->tdtd_lut;
1475         struct lu_attr          *attr = &tti->tti_attr;
1476         struct lu_fid           *fid = &tti->tti_fid1;
1477         struct dt_object_format *dof = &tti->tti_u.update.tti_update_dof;
1478         struct dt_object        *dt_obj = NULL;
1479         struct lu_buf           buf;
1480         __u64                   tmp;
1481         __u64                   off;
1482         int                     rc;
1483         ENTRY;
1484
1485         memset(attr, 0, sizeof(*attr));
1486         attr->la_valid = LA_MODE;
1487         attr->la_mode = S_IFREG | S_IRUGO | S_IWUSR;
1488         dof->dof_type = dt_mode_to_dft(S_IFREG);
1489
1490         lu_local_obj_fid(fid, BATCHID_COMMITTED_OID);
1491
1492         dt_obj = dt_find_or_create(env, lut->lut_bottom, fid, dof,
1493                                    attr);
1494         if (IS_ERR(dt_obj)) {
1495                 rc = PTR_ERR(dt_obj);
1496                 dt_obj = NULL;
1497                 GOTO(out_put, rc);
1498         }
1499
1500         tdtd->tdtd_batchid_obj = dt_obj;
1501
1502         buf.lb_buf = &tmp;
1503         buf.lb_len = sizeof(tmp);
1504         off = 0;
1505         rc = dt_read(env, dt_obj, &buf, &off);
1506         if (rc < 0 || (rc < buf.lb_len && rc > 0)) {
1507                 CERROR("%s can't read last committed batchid: rc = %d\n",
1508                        tdtd->tdtd_lut->lut_obd->obd_name, rc);
1509                 if (rc > 0)
1510                         rc = -EINVAL;
1511                 GOTO(out_put, rc);
1512         } else if (rc == buf.lb_len) {
1513                 tdtd->tdtd_committed_batchid = le64_to_cpu(tmp);
1514                 CDEBUG(D_HA, "%s: committed batchid %llu\n",
1515                        tdtd->tdtd_lut->lut_obd->obd_name,
1516                        tdtd->tdtd_committed_batchid);
1517                 rc = 0;
1518         }
1519
1520 out_put:
1521         if (rc < 0 && dt_obj != NULL) {
1522                 dt_object_put(env, dt_obj);
1523                 tdtd->tdtd_batchid_obj = NULL;
1524         }
1525         return rc;
1526 }
1527
1528 /**
1529  * manage the distribute transaction thread
1530  *
1531  * Distribute transaction are linked to the list, and once the distribute
1532  * transaction is committed, it will update the last committed batchid first,
1533  * after it is committed, it will cancel the records.
1534  *
1535  * \param[in] _arg      argument for commit thread
1536  *
1537  * \retval              0 if thread is running successfully
1538  * \retval              negative errno if the thread can not be run.
1539  */
1540 static int distribute_txn_commit_thread(void *_arg)
1541 {
1542         struct target_distribute_txn_data *tdtd = _arg;
1543         struct lu_target        *lut = tdtd->tdtd_lut;
1544         struct ptlrpc_thread    *thread = &lut->lut_tdtd_commit_thread;
1545         struct l_wait_info       lwi = { 0 };
1546         struct lu_env            env;
1547         struct list_head         list;
1548         int                      rc;
1549         struct top_multiple_thandle *tmt;
1550         struct top_multiple_thandle *tmp;
1551         __u64                    batchid = 0, committed;
1552
1553         ENTRY;
1554
1555         rc = lu_env_init(&env, LCT_LOCAL | LCT_MD_THREAD);
1556         if (rc != 0)
1557                 RETURN(rc);
1558
1559         spin_lock(&tdtd->tdtd_batchid_lock);
1560         thread->t_flags = SVC_RUNNING;
1561         spin_unlock(&tdtd->tdtd_batchid_lock);
1562         wake_up(&thread->t_ctl_waitq);
1563         INIT_LIST_HEAD(&list);
1564
1565         CDEBUG(D_HA, "%s: start commit thread committed batchid %llu\n",
1566                tdtd->tdtd_lut->lut_obd->obd_name,
1567                tdtd->tdtd_committed_batchid);
1568
1569         while (distribute_txn_commit_thread_running(lut)) {
1570                 spin_lock(&tdtd->tdtd_batchid_lock);
1571                 list_for_each_entry_safe(tmt, tmp, &tdtd->tdtd_list,
1572                                          tmt_commit_list) {
1573                         if (tmt->tmt_committed == 0)
1574                                 break;
1575
1576                         /* Note: right now, replay is based on master MDT
1577                          * transno, but cancellation is based on batchid.
1578                          * so we do not try to cancel the update log until
1579                          * the recoverying is done, unless the update records
1580                          * batchid < committed_batchid. */
1581                         if (tmt->tmt_batchid <= tdtd->tdtd_committed_batchid) {
1582                                 list_move_tail(&tmt->tmt_commit_list, &list);
1583                         } else if (!tdtd->tdtd_lut->lut_obd->obd_recovering) {
1584                                 LASSERTF(tmt->tmt_batchid >= batchid,
1585                                          "tmt %p tmt_batchid: %llu, batchid "
1586                                           "%llu\n", tmt, tmt->tmt_batchid,
1587                                          batchid);
1588                                 /* There are three types of distribution
1589                                  * transaction result
1590                                  *
1591                                  * 1. If tmt_result < 0, it means the
1592                                  * distribution transaction fails, which should
1593                                  * be rare, because once declare phase succeeds,
1594                                  * the operation should succeeds anyway. Note in
1595                                  * this case, we will still update batchid so
1596                                  * cancellation would be stopped.
1597                                  *
1598                                  * 2. If tmt_result == 0, it means the
1599                                  * distribution transaction succeeds, and we
1600                                  * will update batchid.
1601                                  *
1602                                  * 3. If tmt_result > 0, it means distribute
1603                                  * transaction is not yet committed on every
1604                                  * node, but we need release this tmt before
1605                                  * that, which usuually happens during umount.
1606                                  */
1607                                 if (tmt->tmt_result <= 0)
1608                                         batchid = tmt->tmt_batchid;
1609                                 list_move_tail(&tmt->tmt_commit_list, &list);
1610                         }
1611                 }
1612                 spin_unlock(&tdtd->tdtd_batchid_lock);
1613
1614                 CDEBUG(D_HA, "%s: batchid: %llu committed batchid "
1615                        "%llu\n", tdtd->tdtd_lut->lut_obd->obd_name, batchid,
1616                        tdtd->tdtd_committed_batchid);
1617                 /* update globally committed on a storage */
1618                 if (batchid > tdtd->tdtd_committed_batchid) {
1619                         rc = distribute_txn_commit_batchid_update(&env, tdtd,
1620                                                              batchid);
1621                         if (rc == 0)
1622                                 batchid = 0;
1623                 }
1624                 /* cancel the records for committed batchid's */
1625                 /* XXX: should we postpone cancel's till the end of recovery? */
1626                 committed = tdtd->tdtd_committed_batchid;
1627                 list_for_each_entry_safe(tmt, tmp, &list, tmt_commit_list) {
1628                         if (tmt->tmt_batchid > committed)
1629                                 break;
1630                         list_del_init(&tmt->tmt_commit_list);
1631                         if (tmt->tmt_result <= 0)
1632                                 distribute_txn_cancel_records(&env, tmt);
1633                         top_multiple_thandle_put(tmt);
1634                 }
1635
1636                 l_wait_event(tdtd->tdtd_commit_thread_waitq,
1637                              !distribute_txn_commit_thread_running(lut) ||
1638                              committed < tdtd->tdtd_committed_batchid ||
1639                              tdtd_ready_for_cancel_log(tdtd), &lwi);
1640         };
1641
1642         l_wait_event(tdtd->tdtd_commit_thread_waitq,
1643                      atomic_read(&tdtd->tdtd_refcount) == 0, &lwi);
1644
1645         spin_lock(&tdtd->tdtd_batchid_lock);
1646         list_for_each_entry_safe(tmt, tmp, &tdtd->tdtd_list,
1647                                  tmt_commit_list)
1648                 list_move_tail(&tmt->tmt_commit_list, &list);
1649         spin_unlock(&tdtd->tdtd_batchid_lock);
1650
1651         CDEBUG(D_INFO, "%s stopping distribute txn commit thread.\n",
1652                tdtd->tdtd_lut->lut_obd->obd_name);
1653         list_for_each_entry_safe(tmt, tmp, &list, tmt_commit_list) {
1654                 list_del_init(&tmt->tmt_commit_list);
1655                 top_multiple_thandle_dump(tmt, D_HA);
1656                 top_multiple_thandle_put(tmt);
1657         }
1658
1659         thread->t_flags = SVC_STOPPED;
1660         lu_env_fini(&env);
1661         wake_up(&thread->t_ctl_waitq);
1662
1663         RETURN(0);
1664 }
1665
1666 /**
1667  * Start llog cancel thread
1668  *
1669  * Start llog cancel(master/slave) thread on LOD
1670  *
1671  * \param[in]lclt       cancel log thread to be started.
1672  *
1673  * \retval              0 if the thread is started successfully.
1674  * \retval              negative errno if the thread is not being
1675  *                      started.
1676  */
1677 int distribute_txn_init(const struct lu_env *env,
1678                         struct lu_target *lut,
1679                         struct target_distribute_txn_data *tdtd,
1680                         __u32 index)
1681 {
1682         struct task_struct      *task;
1683         struct l_wait_info       lwi = { 0 };
1684         int                     rc;
1685         ENTRY;
1686
1687         INIT_LIST_HEAD(&tdtd->tdtd_list);
1688         INIT_LIST_HEAD(&tdtd->tdtd_replay_finish_list);
1689         INIT_LIST_HEAD(&tdtd->tdtd_replay_list);
1690         spin_lock_init(&tdtd->tdtd_batchid_lock);
1691         spin_lock_init(&tdtd->tdtd_replay_list_lock);
1692         tdtd->tdtd_replay_handler = distribute_txn_replay_handle;
1693         tdtd->tdtd_replay_ready = 0;
1694
1695         tdtd->tdtd_batchid = lut->lut_last_transno + 1;
1696
1697         init_waitqueue_head(&lut->lut_tdtd_commit_thread.t_ctl_waitq);
1698         init_waitqueue_head(&tdtd->tdtd_commit_thread_waitq);
1699         init_waitqueue_head(&tdtd->tdtd_recovery_threads_waitq);
1700         atomic_set(&tdtd->tdtd_refcount, 0);
1701         atomic_set(&tdtd->tdtd_recovery_threads_count, 0);
1702
1703         tdtd->tdtd_lut = lut;
1704         if (lut->lut_bottom->dd_rdonly)
1705                 RETURN(0);
1706
1707         rc = distribute_txn_commit_batchid_init(env, tdtd);
1708         if (rc != 0)
1709                 RETURN(rc);
1710
1711         task = kthread_run(distribute_txn_commit_thread, tdtd, "tdtd-%u",
1712                            index);
1713         if (IS_ERR(task))
1714                 RETURN(PTR_ERR(task));
1715
1716         l_wait_event(lut->lut_tdtd_commit_thread.t_ctl_waitq,
1717                      distribute_txn_commit_thread_running(lut) ||
1718                      distribute_txn_commit_thread_stopped(lut), &lwi);
1719         RETURN(0);
1720 }
1721 EXPORT_SYMBOL(distribute_txn_init);
1722
1723 /**
1724  * Stop llog cancel thread
1725  *
1726  * Stop llog cancel(master/slave) thread on LOD and also destory
1727  * all of transaction in the list.
1728  *
1729  * \param[in]lclt       cancel log thread to be stopped.
1730  */
1731 void distribute_txn_fini(const struct lu_env *env,
1732                          struct target_distribute_txn_data *tdtd)
1733 {
1734         struct lu_target *lut = tdtd->tdtd_lut;
1735
1736         /* Stop cancel thread */
1737         if (lut == NULL || !distribute_txn_commit_thread_running(lut))
1738                 return;
1739
1740         spin_lock(&tdtd->tdtd_batchid_lock);
1741         lut->lut_tdtd_commit_thread.t_flags = SVC_STOPPING;
1742         spin_unlock(&tdtd->tdtd_batchid_lock);
1743         wake_up(&tdtd->tdtd_commit_thread_waitq);
1744         wait_event(lut->lut_tdtd_commit_thread.t_ctl_waitq,
1745                    lut->lut_tdtd_commit_thread.t_flags & SVC_STOPPED);
1746
1747         dtrq_list_destroy(tdtd);
1748         if (tdtd->tdtd_batchid_obj != NULL) {
1749                 dt_object_put(env, tdtd->tdtd_batchid_obj);
1750                 tdtd->tdtd_batchid_obj = NULL;
1751         }
1752 }
1753 EXPORT_SYMBOL(distribute_txn_fini);