lustre/target/tgt_lastrcvd.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) 2009, 2010, Oracle and/or its affiliates. All rights reserved.
  24  * Use is subject to license terms.
  25  *
  26  * Copyright (c) 2011, 2016, Intel Corporation.
  27  */
  28 /*
  29  * This file is part of Lustre, http://www.lustre.org/
  30  * Lustre is a trademark of Sun Microsystems, Inc.
  31  *
  32  * Lustre Unified Target
  33  * These are common function to work with last_received file
  34  *
  35  * Author: Mikhail Pershin <mike.pershin@intel.com>
  36  */
  37 #include <obd.h>
  38 #include <obd_class.h>
  39 #include <lustre_fid.h>
  40
  41 #include "tgt_internal.h"
  42
  43
  44 /* Allocate a bitmap for a chunk of reply data slots */
  45 static int tgt_bitmap_chunk_alloc(struct lu_target *lut, int chunk)
  46 {
  47         unsigned long *bm;
  48
  49         OBD_ALLOC_LARGE(bm, BITS_TO_LONGS(LUT_REPLY_SLOTS_PER_CHUNK) *
  50                         sizeof(long));
  51         if (bm == NULL)
  52                 return -ENOMEM;
  53
  54         spin_lock(&lut->lut_client_bitmap_lock);
  55
  56         if (lut->lut_reply_bitmap[chunk] != NULL) {
  57                 /* someone else already allocated the bitmap for this chunk */
  58                 spin_unlock(&lut->lut_client_bitmap_lock);
  59                 OBD_FREE_LARGE(bm, BITS_TO_LONGS(LUT_REPLY_SLOTS_PER_CHUNK) *
  60                          sizeof(long));
  61                 return 0;
  62         }
  63
  64         lut->lut_reply_bitmap[chunk] = bm;
  65
  66         spin_unlock(&lut->lut_client_bitmap_lock);
  67
  68         return 0;
  69 }
  70
  71 /* Look for an available reply data slot in the bitmap
  72  * of the target @lut
  73  * Allocate bitmap chunk when first used
  74  * XXX algo could be improved if this routine limits performance
  75  */
  76 static int tgt_find_free_reply_slot(struct lu_target *lut)
  77 {
  78         unsigned long *bmp;
  79         int chunk = 0;
  80         int rc;
  81         int b;
  82
  83         for (chunk = 0; chunk < LUT_REPLY_SLOTS_MAX_CHUNKS; chunk++) {
  84                 /* allocate the bitmap chunk if necessary */
  85                 if (unlikely(lut->lut_reply_bitmap[chunk] == NULL)) {
  86                         rc = tgt_bitmap_chunk_alloc(lut, chunk);
  87                         if (rc != 0)
  88                                 return rc;
  89                 }
  90                 bmp = lut->lut_reply_bitmap[chunk];
  91
  92                 /* look for an available slot in this chunk */
  93                 do {
  94                         b = find_first_zero_bit(bmp, LUT_REPLY_SLOTS_PER_CHUNK);
  95                         if (b >= LUT_REPLY_SLOTS_PER_CHUNK)
  96                                 break;
  97
  98                         /* found one */
  99                         if (test_and_set_bit(b, bmp) == 0)
 100                                 return chunk * LUT_REPLY_SLOTS_PER_CHUNK + b;
 101                 } while (true);
 102         }
 103
 104         return -ENOSPC;
 105 }
 106
 107 /* Mark the reply data slot @idx 'used' in the corresponding bitmap chunk
 108  * of the target @lut
 109  * Allocate the bitmap chunk if necessary
 110  */
 111 static int tgt_set_reply_slot(struct lu_target *lut, int idx)
 112 {
 113         int chunk;
 114         int b;
 115         int rc;
 116
 117         chunk = idx / LUT_REPLY_SLOTS_PER_CHUNK;
 118         b = idx % LUT_REPLY_SLOTS_PER_CHUNK;
 119
 120         LASSERT(chunk < LUT_REPLY_SLOTS_MAX_CHUNKS);
 121         LASSERT(b < LUT_REPLY_SLOTS_PER_CHUNK);
 122
 123         /* allocate the bitmap chunk if necessary */
 124         if (unlikely(lut->lut_reply_bitmap[chunk] == NULL)) {
 125                 rc = tgt_bitmap_chunk_alloc(lut, chunk);
 126                 if (rc != 0)
 127                         return rc;
 128         }
 129
 130         /* mark the slot 'used' in this chunk */
 131         if (test_and_set_bit(b, lut->lut_reply_bitmap[chunk]) != 0) {
 132                 CERROR("%s: slot %d already set in bitmap\n",
 133                        tgt_name(lut), idx);
 134                 return -EALREADY;
 135         }
 136
 137         return 0;
 138 }
 139
 140
 141 /* Mark the reply data slot @idx 'unused' in the corresponding bitmap chunk
 142  * of the target @lut
 143  */
 144 static int tgt_clear_reply_slot(struct lu_target *lut, int idx)
 145 {
 146         int chunk;
 147         int b;
 148
 149         chunk = idx / LUT_REPLY_SLOTS_PER_CHUNK;
 150         b = idx % LUT_REPLY_SLOTS_PER_CHUNK;
 151
 152         LASSERT(chunk < LUT_REPLY_SLOTS_MAX_CHUNKS);
 153         LASSERT(b < LUT_REPLY_SLOTS_PER_CHUNK);
 154
 155         if (lut->lut_reply_bitmap[chunk] == NULL) {
 156                 CERROR("%s: slot %d not allocated\n",
 157                        tgt_name(lut), idx);
 158                 return -ENOENT;
 159         }
 160
 161         if (test_and_clear_bit(b, lut->lut_reply_bitmap[chunk]) == 0) {
 162                 CERROR("%s: slot %d already clear in bitmap\n",
 163                        tgt_name(lut), idx);
 164                 return -EALREADY;
 165         }
 166
 167         return 0;
 168 }
 169
 170
 171 /* Read header of reply_data file of target @tgt into structure @lrh */
 172 static int tgt_reply_header_read(const struct lu_env *env,
 173                                  struct lu_target *tgt,
 174                                  struct lsd_reply_header *lrh)
 175 {
 176         int                      rc;
 177         struct lsd_reply_header  buf;
 178         struct tgt_thread_info  *tti = tgt_th_info(env);
 179
 180         tti->tti_off = 0;
 181         tti->tti_buf.lb_buf = &buf;
 182         tti->tti_buf.lb_len = sizeof(buf);
 183
 184         rc = dt_record_read(env, tgt->lut_reply_data, &tti->tti_buf,
 185                             &tti->tti_off);
 186         if (rc != 0)
 187                 return rc;
 188
 189         lrh->lrh_magic = le32_to_cpu(buf.lrh_magic);
 190         lrh->lrh_header_size = le32_to_cpu(buf.lrh_header_size);
 191         lrh->lrh_reply_size = le32_to_cpu(buf.lrh_reply_size);
 192
 193         CDEBUG(D_HA, "%s: read %s header. magic=0x%08x "
 194                "header_size=%d reply_size=%d\n",
 195                 tgt->lut_obd->obd_name, REPLY_DATA,
 196                 lrh->lrh_magic, lrh->lrh_header_size, lrh->lrh_reply_size);
 197
 198         return 0;
 199 }
 200
 201 /* Write header into replay_data file of target @tgt from structure @lrh */
 202 static int tgt_reply_header_write(const struct lu_env *env,
 203                                   struct lu_target *tgt,
 204                                   struct lsd_reply_header *lrh)
 205 {
 206         int                      rc;
 207         struct lsd_reply_header  buf;
 208         struct tgt_thread_info  *tti = tgt_th_info(env);
 209         struct thandle          *th;
 210         struct dt_object        *dto;
 211
 212         CDEBUG(D_HA, "%s: write %s header. magic=0x%08x "
 213                "header_size=%d reply_size=%d\n",
 214                 tgt->lut_obd->obd_name, REPLY_DATA,
 215                 lrh->lrh_magic, lrh->lrh_header_size, lrh->lrh_reply_size);
 216
 217         buf.lrh_magic = cpu_to_le32(lrh->lrh_magic);
 218         buf.lrh_header_size = cpu_to_le32(lrh->lrh_header_size);
 219         buf.lrh_reply_size = cpu_to_le32(lrh->lrh_reply_size);
 220
 221         th = dt_trans_create(env, tgt->lut_bottom);
 222         if (IS_ERR(th))
 223                 return PTR_ERR(th);
 224         th->th_sync = 1;
 225
 226         tti->tti_off = 0;
 227         tti->tti_buf.lb_buf = &buf;
 228         tti->tti_buf.lb_len = sizeof(buf);
 229
 230         rc = dt_declare_record_write(env, tgt->lut_reply_data,
 231                                      &tti->tti_buf, tti->tti_off, th);
 232         if (rc)
 233                 GOTO(out, rc);
 234
 235         rc = dt_trans_start(env, tgt->lut_bottom, th);
 236         if (rc)
 237                 GOTO(out, rc);
 238
 239         dto = dt_object_locate(tgt->lut_reply_data, th->th_dev);
 240         rc = dt_record_write(env, dto, &tti->tti_buf, &tti->tti_off, th);
 241 out:
 242         dt_trans_stop(env, tgt->lut_bottom, th);
 243         return rc;
 244 }
 245
 246 /* Write the reply data @lrd into reply_data file of target @tgt
 247  * at offset @off
 248  */
 249 static int tgt_reply_data_write(const struct lu_env *env, struct lu_target *tgt,
 250                                 struct lsd_reply_data *lrd, loff_t off,
 251                                 struct thandle *th)
 252 {
 253         struct tgt_thread_info  *tti = tgt_th_info(env);
 254         struct dt_object        *dto;
 255         struct lsd_reply_data   *buf = &tti->tti_lrd;
 256
 257         lrd->lrd_result = ptlrpc_status_hton(lrd->lrd_result);
 258
 259         buf->lrd_transno         = cpu_to_le64(lrd->lrd_transno);
 260         buf->lrd_xid             = cpu_to_le64(lrd->lrd_xid);
 261         buf->lrd_data            = cpu_to_le64(lrd->lrd_data);
 262         buf->lrd_result          = cpu_to_le32(lrd->lrd_result);
 263         buf->lrd_client_gen      = cpu_to_le32(lrd->lrd_client_gen);
 264
 265         lrd->lrd_result = ptlrpc_status_ntoh(lrd->lrd_result);
 266
 267         tti->tti_off = off;
 268         tti->tti_buf.lb_buf = buf;
 269         tti->tti_buf.lb_len = sizeof(*buf);
 270
 271         dto = dt_object_locate(tgt->lut_reply_data, th->th_dev);
 272         return dt_record_write(env, dto, &tti->tti_buf, &tti->tti_off, th);
 273 }
 274
 275 /* Read the reply data from reply_data file of target @tgt at offset @off
 276  * into structure @lrd
 277  */
 278 static int tgt_reply_data_read(const struct lu_env *env, struct lu_target *tgt,
 279                                struct lsd_reply_data *lrd, loff_t off)
 280 {
 281         int                      rc;
 282         struct tgt_thread_info  *tti = tgt_th_info(env);
 283         struct lsd_reply_data   *buf = &tti->tti_lrd;
 284
 285         tti->tti_off = off;
 286         tti->tti_buf.lb_buf = buf;
 287         tti->tti_buf.lb_len = sizeof(*buf);
 288
 289         rc = dt_record_read(env, tgt->lut_reply_data, &tti->tti_buf,
 290                             &tti->tti_off);
 291         if (rc != 0)
 292                 return rc;
 293
 294         lrd->lrd_transno         = le64_to_cpu(buf->lrd_transno);
 295         lrd->lrd_xid             = le64_to_cpu(buf->lrd_xid);
 296         lrd->lrd_data            = le64_to_cpu(buf->lrd_data);
 297         lrd->lrd_result          = le32_to_cpu(buf->lrd_result);
 298         lrd->lrd_client_gen      = le32_to_cpu(buf->lrd_client_gen);
 299
 300         return 0;
 301 }
 302
 303
 304 /* Free the in-memory reply data structure @trd and release
 305  * the corresponding slot in the reply_data file of target @lut
 306  * Called with ted_lcd_lock held
 307  */
 308 static void tgt_free_reply_data(struct lu_target *lut,
 309                                 struct tg_export_data *ted,
 310                                 struct tg_reply_data *trd)
 311 {
 312         CDEBUG(D_TRACE, "%s: free reply data %p: xid %llu, transno %llu, "
 313                "client gen %u, slot idx %d\n",
 314                lut == NULL ? "" : tgt_name(lut), trd, trd->trd_reply.lrd_xid,
 315                trd->trd_reply.lrd_transno, trd->trd_reply.lrd_client_gen,
 316                trd->trd_index);
 317
 318         LASSERT(mutex_is_locked(&ted->ted_lcd_lock));
 319
 320         list_del(&trd->trd_list);
 321         ted->ted_reply_cnt--;
 322         if (lut != NULL)
 323                 tgt_clear_reply_slot(lut, trd->trd_index);
 324         OBD_FREE_PTR(trd);
 325 }
 326
 327 /* Release the reply data @trd from target @lut
 328  * The reply data with the highest transno for this export
 329  * is retained to ensure correctness of target recovery
 330  * Called with ted_lcd_lock held
 331  */
 332 static void tgt_release_reply_data(struct lu_target *lut,
 333                                    struct tg_export_data *ted,
 334                                    struct tg_reply_data *trd)
 335 {
 336         CDEBUG(D_TRACE, "%s: release reply data %p: xid %llu, transno %llu, "
 337                "client gen %u, slot idx %d\n",
 338                lut == NULL ? "" : tgt_name(lut), trd, trd->trd_reply.lrd_xid,
 339                trd->trd_reply.lrd_transno, trd->trd_reply.lrd_client_gen,
 340                trd->trd_index);
 341
 342         LASSERT(mutex_is_locked(&ted->ted_lcd_lock));
 343
 344         /* Do not free the reply data corresponding to the
 345          * highest transno of this export.
 346          * This ensures on-disk reply data is kept and
 347          * last committed transno can be restored from disk in case
 348          * of target recovery
 349          */
 350         if (trd->trd_reply.lrd_transno == ted->ted_lcd->lcd_last_transno) {
 351                 /* free previous retained reply */
 352                 if (ted->ted_reply_last != NULL)
 353                         tgt_free_reply_data(lut, ted, ted->ted_reply_last);
 354                 /* retain the reply */
 355                 list_del_init(&trd->trd_list);
 356                 ted->ted_reply_last = trd;
 357         } else {
 358                 tgt_free_reply_data(lut, ted, trd);
 359         }
 360 }
 361
 362 static inline struct lu_buf *tti_buf_lsd(struct tgt_thread_info *tti)
 363 {
 364         tti->tti_buf.lb_buf = &tti->tti_lsd;
 365         tti->tti_buf.lb_len = sizeof(tti->tti_lsd);
 366         return &tti->tti_buf;
 367 }
 368
 369 static inline struct lu_buf *tti_buf_lcd(struct tgt_thread_info *tti)
 370 {
 371         tti->tti_buf.lb_buf = &tti->tti_lcd;
 372         tti->tti_buf.lb_len = sizeof(tti->tti_lcd);
 373         return &tti->tti_buf;
 374 }
 375
 376 /**
 377  * Allocate in-memory data for client slot related to export.
 378  */
 379 int tgt_client_alloc(struct obd_export *exp)
 380 {
 381         ENTRY;
 382         LASSERT(exp != exp->exp_obd->obd_self_export);
 383
 384         spin_lock_init(&exp->exp_target_data.ted_nodemap_lock);
 385         INIT_LIST_HEAD(&exp->exp_target_data.ted_nodemap_member);
 386
 387         OBD_ALLOC_PTR(exp->exp_target_data.ted_lcd);
 388         if (exp->exp_target_data.ted_lcd == NULL)
 389                 RETURN(-ENOMEM);
 390         /* Mark that slot is not yet valid, 0 doesn't work here */
 391         exp->exp_target_data.ted_lr_idx = -1;
 392         INIT_LIST_HEAD(&exp->exp_target_data.ted_reply_list);
 393         mutex_init(&exp->exp_target_data.ted_lcd_lock);
 394         RETURN(0);
 395 }
 396 EXPORT_SYMBOL(tgt_client_alloc);
 397
 398 /**
 399  * Free in-memory data for client slot related to export.
 400  */
 401 void tgt_client_free(struct obd_export *exp)
 402 {
 403         struct tg_export_data   *ted = &exp->exp_target_data;
 404         struct lu_target        *lut = class_exp2tgt(exp);
 405         struct tg_reply_data    *trd, *tmp;
 406
 407         LASSERT(exp != exp->exp_obd->obd_self_export);
 408
 409         /* free reply data */
 410         mutex_lock(&ted->ted_lcd_lock);
 411         list_for_each_entry_safe(trd, tmp, &ted->ted_reply_list, trd_list) {
 412                 tgt_release_reply_data(lut, ted, trd);
 413         }
 414         if (ted->ted_reply_last != NULL) {
 415                 tgt_free_reply_data(lut, ted, ted->ted_reply_last);
 416                 ted->ted_reply_last = NULL;
 417         }
 418         mutex_unlock(&ted->ted_lcd_lock);
 419
 420         if (!hlist_unhashed(&exp->exp_gen_hash))
 421                 cfs_hash_del(exp->exp_obd->obd_gen_hash,
 422                              &ted->ted_lcd->lcd_generation,
 423                              &exp->exp_gen_hash);
 424
 425         OBD_FREE_PTR(ted->ted_lcd);
 426         ted->ted_lcd = NULL;
 427
 428         /* Target may have been freed (see LU-7430)
 429          * Slot may be not yet assigned */
 430         if (exp->exp_obd->u.obt.obt_magic != OBT_MAGIC ||
 431             ted->ted_lr_idx < 0)
 432                 return;
 433
 434         /* Clear bit when lcd is freed */
 435         LASSERT(lut && lut->lut_client_bitmap);
 436         if (!test_and_clear_bit(ted->ted_lr_idx, lut->lut_client_bitmap)) {
 437                 CERROR("%s: client %u bit already clear in bitmap\n",
 438                        exp->exp_obd->obd_name, ted->ted_lr_idx);
 439                 LBUG();
 440         }
 441
 442         if (tgt_is_multimodrpcs_client(exp) && !exp->exp_obd->obd_stopping)
 443                 atomic_dec(&lut->lut_num_clients);
 444 }
 445 EXPORT_SYMBOL(tgt_client_free);
 446
 447 int tgt_client_data_read(const struct lu_env *env, struct lu_target *tgt,
 448                          struct lsd_client_data *lcd, loff_t *off, int index)
 449 {
 450         struct tgt_thread_info  *tti = tgt_th_info(env);
 451         int                      rc;
 452
 453         tti_buf_lcd(tti);
 454         rc = dt_record_read(env, tgt->lut_last_rcvd, &tti->tti_buf, off);
 455         if (rc == 0) {
 456                 check_lcd(tgt->lut_obd->obd_name, index, &tti->tti_lcd);
 457                 lcd_le_to_cpu(&tti->tti_lcd, lcd);
 458                 lcd->lcd_last_result = ptlrpc_status_ntoh(lcd->lcd_last_result);
 459                 lcd->lcd_last_close_result =
 460                         ptlrpc_status_ntoh(lcd->lcd_last_close_result);
 461         }
 462
 463         CDEBUG(D_INFO, "%s: read lcd @%lld uuid = %s, last_transno = %llu"
 464                ", last_xid = %llu, last_result = %u, last_data = %u, "
 465                "last_close_transno = %llu, last_close_xid = %llu, "
 466                "last_close_result = %u, rc = %d\n", tgt->lut_obd->obd_name,
 467                *off, lcd->lcd_uuid, lcd->lcd_last_transno, lcd->lcd_last_xid,
 468                lcd->lcd_last_result, lcd->lcd_last_data,
 469                lcd->lcd_last_close_transno, lcd->lcd_last_close_xid,
 470                lcd->lcd_last_close_result, rc);
 471         return rc;
 472 }
 473
 474 int tgt_client_data_write(const struct lu_env *env, struct lu_target *tgt,
 475                           struct lsd_client_data *lcd, loff_t *off,
 476                           struct thandle *th)
 477 {
 478         struct tgt_thread_info *tti = tgt_th_info(env);
 479         struct dt_object        *dto;
 480
 481         lcd->lcd_last_result = ptlrpc_status_hton(lcd->lcd_last_result);
 482         lcd->lcd_last_close_result =
 483                 ptlrpc_status_hton(lcd->lcd_last_close_result);
 484         lcd_cpu_to_le(lcd, &tti->tti_lcd);
 485         tti_buf_lcd(tti);
 486
 487         dto = dt_object_locate(tgt->lut_last_rcvd, th->th_dev);
 488         return dt_record_write(env, dto, &tti->tti_buf, off, th);
 489 }
 490
 491 /**
 492  * Update client data in last_rcvd
 493  */
 494 static int tgt_client_data_update(const struct lu_env *env,
 495                                   struct obd_export *exp)
 496 {
 497         struct tg_export_data   *ted = &exp->exp_target_data;
 498         struct lu_target        *tgt = class_exp2tgt(exp);
 499         struct tgt_thread_info  *tti = tgt_th_info(env);
 500         struct thandle          *th;
 501         int                      rc = 0;
 502
 503         ENTRY;
 504
 505         if (unlikely(tgt == NULL)) {
 506                 CDEBUG(D_ERROR, "%s: No target for connected export\n",
 507                           class_exp2obd(exp)->obd_name);
 508                 RETURN(-EINVAL);
 509         }
 510
 511         th = dt_trans_create(env, tgt->lut_bottom);
 512         if (IS_ERR(th))
 513                 RETURN(PTR_ERR(th));
 514
 515         tti_buf_lcd(tti);
 516         rc = dt_declare_record_write(env, tgt->lut_last_rcvd,
 517                                      &tti->tti_buf,
 518                                      ted->ted_lr_off, th);
 519         if (rc)
 520                 GOTO(out, rc);
 521
 522         rc = dt_trans_start_local(env, tgt->lut_bottom, th);
 523         if (rc)
 524                 GOTO(out, rc);
 525
 526         mutex_lock(&ted->ted_lcd_lock);
 527
 528         /*
 529          * Until this operations will be committed the sync is needed
 530          * for this export. This should be done _after_ starting the
 531          * transaction so that many connecting clients will not bring
 532          * server down with lots of sync writes.
 533          */
 534         rc = tgt_new_client_cb_add(th, exp);
 535         if (rc) {
 536                 /* can't add callback, do sync now */
 537                 th->th_sync = 1;
 538         } else {
 539                 spin_lock(&exp->exp_lock);
 540                 exp->exp_need_sync = 1;
 541                 spin_unlock(&exp->exp_lock);
 542         }
 543
 544         tti->tti_off = ted->ted_lr_off;
 545         rc = tgt_client_data_write(env, tgt, ted->ted_lcd, &tti->tti_off, th);
 546
 547         mutex_unlock(&ted->ted_lcd_lock);
 548
 549         EXIT;
 550 out:
 551         dt_trans_stop(env, tgt->lut_bottom, th);
 552         CDEBUG(D_INFO, "%s: update last_rcvd client data for UUID = %s, "
 553                "last_transno = %llu: rc = %d\n", tgt->lut_obd->obd_name,
 554                tgt->lut_lsd.lsd_uuid, tgt->lut_lsd.lsd_last_transno, rc);
 555
 556         return rc;
 557 }
 558
 559 int tgt_server_data_read(const struct lu_env *env, struct lu_target *tgt)
 560 {
 561         struct tgt_thread_info  *tti = tgt_th_info(env);
 562         int                      rc;
 563
 564         tti->tti_off = 0;
 565         tti_buf_lsd(tti);
 566         rc = dt_record_read(env, tgt->lut_last_rcvd, &tti->tti_buf,
 567                             &tti->tti_off);
 568         if (rc == 0)
 569                 lsd_le_to_cpu(&tti->tti_lsd, &tgt->lut_lsd);
 570
 571         CDEBUG(D_INFO, "%s: read last_rcvd server data for UUID = %s, "
 572                "last_transno = %llu: rc = %d\n", tgt->lut_obd->obd_name,
 573                tgt->lut_lsd.lsd_uuid, tgt->lut_lsd.lsd_last_transno, rc);
 574         return rc;
 575 }
 576
 577 int tgt_server_data_write(const struct lu_env *env, struct lu_target *tgt,
 578                           struct thandle *th)
 579 {
 580         struct tgt_thread_info  *tti = tgt_th_info(env);
 581         struct dt_object        *dto;
 582         int                      rc;
 583
 584         ENTRY;
 585
 586         tti->tti_off = 0;
 587         tti_buf_lsd(tti);
 588         lsd_cpu_to_le(&tgt->lut_lsd, &tti->tti_lsd);
 589
 590         dto = dt_object_locate(tgt->lut_last_rcvd, th->th_dev);
 591         rc = dt_record_write(env, dto, &tti->tti_buf, &tti->tti_off, th);
 592
 593         CDEBUG(D_INFO, "%s: write last_rcvd server data for UUID = %s, "
 594                "last_transno = %llu: rc = %d\n", tgt->lut_obd->obd_name,
 595                tgt->lut_lsd.lsd_uuid, tgt->lut_lsd.lsd_last_transno, rc);
 596
 597         RETURN(rc);
 598 }
 599
 600 /**
 601  * Update server data in last_rcvd
 602  */
 603 int tgt_server_data_update(const struct lu_env *env, struct lu_target *tgt,
 604                            int sync)
 605 {
 606         struct tgt_thread_info  *tti = tgt_th_info(env);
 607         struct thandle          *th;
 608         int                      rc = 0;
 609
 610         ENTRY;
 611
 612         CDEBUG(D_SUPER,
 613                "%s: mount_count is %llu, last_transno is %llu\n",
 614                tgt->lut_lsd.lsd_uuid, tgt->lut_obd->u.obt.obt_mount_count,
 615                tgt->lut_last_transno);
 616
 617         /* Always save latest transno to keep it fresh */
 618         spin_lock(&tgt->lut_translock);
 619         tgt->lut_lsd.lsd_last_transno = tgt->lut_last_transno;
 620         spin_unlock(&tgt->lut_translock);
 621
 622         th = dt_trans_create(env, tgt->lut_bottom);
 623         if (IS_ERR(th))
 624                 RETURN(PTR_ERR(th));
 625
 626         th->th_sync = sync;
 627
 628         tti_buf_lsd(tti);
 629         rc = dt_declare_record_write(env, tgt->lut_last_rcvd,
 630                                      &tti->tti_buf, tti->tti_off, th);
 631         if (rc)
 632                 GOTO(out, rc);
 633
 634         rc = dt_trans_start(env, tgt->lut_bottom, th);
 635         if (rc)
 636                 GOTO(out, rc);
 637
 638         rc = tgt_server_data_write(env, tgt, th);
 639 out:
 640         dt_trans_stop(env, tgt->lut_bottom, th);
 641
 642         CDEBUG(D_INFO, "%s: update last_rcvd server data for UUID = %s, "
 643                "last_transno = %llu: rc = %d\n", tgt->lut_obd->obd_name,
 644                tgt->lut_lsd.lsd_uuid, tgt->lut_lsd.lsd_last_transno, rc);
 645         RETURN(rc);
 646 }
 647 EXPORT_SYMBOL(tgt_server_data_update);
 648
 649 int tgt_truncate_last_rcvd(const struct lu_env *env, struct lu_target *tgt,
 650                            loff_t size)
 651 {
 652         struct dt_object *dt = tgt->lut_last_rcvd;
 653         struct thandle   *th;
 654         struct lu_attr    attr;
 655         int               rc;
 656
 657         ENTRY;
 658
 659         attr.la_size = size;
 660         attr.la_valid = LA_SIZE;
 661
 662         th = dt_trans_create(env, tgt->lut_bottom);
 663         if (IS_ERR(th))
 664                 RETURN(PTR_ERR(th));
 665         rc = dt_declare_punch(env, dt, size, OBD_OBJECT_EOF, th);
 666         if (rc)
 667                 GOTO(cleanup, rc);
 668         rc = dt_declare_attr_set(env, dt, &attr, th);
 669         if (rc)
 670                 GOTO(cleanup, rc);
 671         rc = dt_trans_start_local(env, tgt->lut_bottom, th);
 672         if (rc)
 673                 GOTO(cleanup, rc);
 674
 675         rc = dt_punch(env, dt, size, OBD_OBJECT_EOF, th);
 676         if (rc == 0)
 677                 rc = dt_attr_set(env, dt, &attr, th);
 678
 679 cleanup:
 680         dt_trans_stop(env, tgt->lut_bottom, th);
 681
 682         RETURN(rc);
 683 }
 684
 685 static void tgt_client_epoch_update(const struct lu_env *env,
 686                                     struct obd_export *exp)
 687 {
 688         struct lsd_client_data  *lcd = exp->exp_target_data.ted_lcd;
 689         struct lu_target        *tgt = class_exp2tgt(exp);
 690
 691         LASSERT(tgt && tgt->lut_bottom);
 692         /** VBR: set client last_epoch to current epoch */
 693         if (lcd->lcd_last_epoch >= tgt->lut_lsd.lsd_start_epoch)
 694                 return;
 695         lcd->lcd_last_epoch = tgt->lut_lsd.lsd_start_epoch;
 696         tgt_client_data_update(env, exp);
 697 }
 698
 699 /**
 700  * Update boot epoch when recovery ends
 701  */
 702 void tgt_boot_epoch_update(struct lu_target *tgt)
 703 {
 704         struct lu_env            env;
 705         struct ptlrpc_request   *req;
 706         __u32                    start_epoch;
 707         struct list_head         client_list;
 708         int                      rc;
 709
 710         if (tgt->lut_obd->obd_stopping)
 711                 return;
 712
 713         rc = lu_env_init(&env, LCT_DT_THREAD);
 714         if (rc) {
 715                 CERROR("%s: can't initialize environment: rc = %d\n",
 716                         tgt->lut_obd->obd_name, rc);
 717                 return;
 718         }
 719
 720         spin_lock(&tgt->lut_translock);
 721         start_epoch = lr_epoch(tgt->lut_last_transno) + 1;
 722         tgt->lut_last_transno = (__u64)start_epoch << LR_EPOCH_BITS;
 723         tgt->lut_lsd.lsd_start_epoch = start_epoch;
 724         spin_unlock(&tgt->lut_translock);
 725
 726         INIT_LIST_HEAD(&client_list);
 727         /**
 728          * The recovery is not yet finished and final queue can still be updated
 729          * with resend requests. Move final list to separate one for processing
 730          */
 731         spin_lock(&tgt->lut_obd->obd_recovery_task_lock);
 732         list_splice_init(&tgt->lut_obd->obd_final_req_queue, &client_list);
 733         spin_unlock(&tgt->lut_obd->obd_recovery_task_lock);
 734
 735         /**
 736          * go through list of exports participated in recovery and
 737          * set new epoch for them
 738          */
 739         list_for_each_entry(req, &client_list, rq_list) {
 740                 LASSERT(!req->rq_export->exp_delayed);
 741                 if (!req->rq_export->exp_vbr_failed)
 742                         tgt_client_epoch_update(&env, req->rq_export);
 743         }
 744         /** return list back at once */
 745         spin_lock(&tgt->lut_obd->obd_recovery_task_lock);
 746         list_splice_init(&client_list, &tgt->lut_obd->obd_final_req_queue);
 747         spin_unlock(&tgt->lut_obd->obd_recovery_task_lock);
 748
 749         /** Clear MULTI RPCS incompatibility flag if
 750          * - target is MDT and
 751          * - there is no client to recover or the recovery was aborted
 752          */
 753         if (!strncmp(tgt->lut_obd->obd_type->typ_name, LUSTRE_MDT_NAME, 3) &&
 754             (tgt->lut_obd->obd_max_recoverable_clients == 0 ||
 755             tgt->lut_obd->obd_abort_recovery))
 756                 tgt->lut_lsd.lsd_feature_incompat &= ~OBD_INCOMPAT_MULTI_RPCS;
 757
 758         /** update server epoch */
 759         tgt_server_data_update(&env, tgt, 1);
 760         lu_env_fini(&env);
 761 }
 762
 763 /**
 764  * commit callback, need to update last_committed value
 765  */
 766 struct tgt_last_committed_callback {
 767         struct dt_txn_commit_cb  llcc_cb;
 768         struct lu_target        *llcc_tgt;
 769         struct obd_export       *llcc_exp;
 770         __u64                    llcc_transno;
 771 };
 772
 773 static void tgt_cb_last_committed(struct lu_env *env, struct thandle *th,
 774                                   struct dt_txn_commit_cb *cb, int err)
 775 {
 776         struct tgt_last_committed_callback *ccb;
 777
 778         ccb = container_of0(cb, struct tgt_last_committed_callback, llcc_cb);
 779
 780         LASSERT(ccb->llcc_exp);
 781         LASSERT(ccb->llcc_tgt != NULL);
 782         LASSERT(ccb->llcc_exp->exp_obd == ccb->llcc_tgt->lut_obd);
 783
 784         /* error hit, don't update last committed to provide chance to
 785          * replay data after fail */
 786         if (err != 0)
 787                 goto out;
 788
 789         /* Fast path w/o spinlock, if exp_last_committed was updated
 790          * with higher transno, no need to take spinlock and check,
 791          * also no need to update obd_last_committed. */
 792         if (ccb->llcc_transno <= ccb->llcc_exp->exp_last_committed)
 793                 goto out;
 794         spin_lock(&ccb->llcc_tgt->lut_translock);
 795         if (ccb->llcc_transno > ccb->llcc_tgt->lut_obd->obd_last_committed)
 796                 ccb->llcc_tgt->lut_obd->obd_last_committed = ccb->llcc_transno;
 797
 798         if (ccb->llcc_transno > ccb->llcc_exp->exp_last_committed) {
 799                 ccb->llcc_exp->exp_last_committed = ccb->llcc_transno;
 800                 spin_unlock(&ccb->llcc_tgt->lut_translock);
 801
 802                 ptlrpc_commit_replies(ccb->llcc_exp);
 803                 tgt_cancel_slc_locks(ccb->llcc_tgt, ccb->llcc_transno);
 804         } else {
 805                 spin_unlock(&ccb->llcc_tgt->lut_translock);
 806         }
 807
 808         CDEBUG(D_HA, "%s: transno %lld is committed\n",
 809                ccb->llcc_tgt->lut_obd->obd_name, ccb->llcc_transno);
 810
 811 out:
 812         class_export_cb_put(ccb->llcc_exp);
 813         OBD_FREE_PTR(ccb);
 814 }
 815
 816 /**
 817  * Add commit callback function, it returns a non-zero value to inform
 818  * caller to use sync transaction if necessary.
 819  */
 820 int tgt_last_commit_cb_add(struct thandle *th, struct lu_target *tgt,
 821                            struct obd_export *exp, __u64 transno)
 822 {
 823         struct tgt_last_committed_callback      *ccb;
 824         struct dt_txn_commit_cb                 *dcb;
 825         int                                      rc;
 826
 827         OBD_ALLOC_PTR(ccb);
 828         if (ccb == NULL)
 829                 return -ENOMEM;
 830
 831         ccb->llcc_tgt = tgt;
 832         ccb->llcc_exp = class_export_cb_get(exp);
 833         ccb->llcc_transno = transno;
 834
 835         dcb = &ccb->llcc_cb;
 836         dcb->dcb_func = tgt_cb_last_committed;
 837         INIT_LIST_HEAD(&dcb->dcb_linkage);
 838         strlcpy(dcb->dcb_name, "tgt_cb_last_committed", sizeof(dcb->dcb_name));
 839
 840         rc = dt_trans_cb_add(th, dcb);
 841         if (rc) {
 842                 class_export_cb_put(exp);
 843                 OBD_FREE_PTR(ccb);
 844         }
 845
 846         if (exp_connect_flags(exp) & OBD_CONNECT_LIGHTWEIGHT)
 847                 /* report failure to force synchronous operation */
 848                 return -EPERM;
 849
 850         /* if exp_need_sync is set, return non-zero value to force
 851          * a sync transaction. */
 852         return rc ? rc : exp->exp_need_sync;
 853 }
 854
 855 struct tgt_new_client_callback {
 856         struct dt_txn_commit_cb  lncc_cb;
 857         struct obd_export       *lncc_exp;
 858 };
 859
 860 static void tgt_cb_new_client(struct lu_env *env, struct thandle *th,
 861                               struct dt_txn_commit_cb *cb, int err)
 862 {
 863         struct tgt_new_client_callback *ccb;
 864
 865         ccb = container_of0(cb, struct tgt_new_client_callback, lncc_cb);
 866
 867         LASSERT(ccb->lncc_exp->exp_obd);
 868
 869         CDEBUG(D_RPCTRACE, "%s: committing for initial connect of %s\n",
 870                ccb->lncc_exp->exp_obd->obd_name,
 871                ccb->lncc_exp->exp_client_uuid.uuid);
 872
 873         spin_lock(&ccb->lncc_exp->exp_lock);
 874
 875         ccb->lncc_exp->exp_need_sync = 0;
 876
 877         spin_unlock(&ccb->lncc_exp->exp_lock);
 878         class_export_cb_put(ccb->lncc_exp);
 879
 880         OBD_FREE_PTR(ccb);
 881 }
 882
 883 int tgt_new_client_cb_add(struct thandle *th, struct obd_export *exp)
 884 {
 885         struct tgt_new_client_callback  *ccb;
 886         struct dt_txn_commit_cb         *dcb;
 887         int                              rc;
 888
 889         OBD_ALLOC_PTR(ccb);
 890         if (ccb == NULL)
 891                 return -ENOMEM;
 892
 893         ccb->lncc_exp = class_export_cb_get(exp);
 894
 895         dcb = &ccb->lncc_cb;
 896         dcb->dcb_func = tgt_cb_new_client;
 897         INIT_LIST_HEAD(&dcb->dcb_linkage);
 898         strlcpy(dcb->dcb_name, "tgt_cb_new_client", sizeof(dcb->dcb_name));
 899
 900         rc = dt_trans_cb_add(th, dcb);
 901         if (rc) {
 902                 class_export_cb_put(exp);
 903                 OBD_FREE_PTR(ccb);
 904         }
 905         return rc;
 906 }
 907
 908 /**
 909  * Add new client to the last_rcvd upon new connection.
 910  *
 911  * We use a bitmap to locate a free space in the last_rcvd file and initialize
 912  * tg_export_data.
 913  */
 914 int tgt_client_new(const struct lu_env *env, struct obd_export *exp)
 915 {
 916         struct tg_export_data   *ted = &exp->exp_target_data;
 917         struct lu_target        *tgt = class_exp2tgt(exp);
 918         int                      rc = 0, idx;
 919
 920         ENTRY;
 921
 922         LASSERT(tgt && tgt->lut_client_bitmap != NULL);
 923         if (!strcmp(ted->ted_lcd->lcd_uuid, tgt->lut_obd->obd_uuid.uuid))
 924                 RETURN(0);
 925
 926         if (exp_connect_flags(exp) & OBD_CONNECT_LIGHTWEIGHT)
 927                 RETURN(0);
 928
 929         /* the bitmap operations can handle cl_idx > sizeof(long) * 8, so
 930          * there's no need for extra complication here
 931          */
 932         idx = find_first_zero_bit(tgt->lut_client_bitmap, LR_MAX_CLIENTS);
 933 repeat:
 934         if (idx >= LR_MAX_CLIENTS ||
 935             OBD_FAIL_CHECK(OBD_FAIL_MDS_CLIENT_ADD)) {
 936                 CERROR("%s: no room for %u clients - fix LR_MAX_CLIENTS\n",
 937                        tgt->lut_obd->obd_name,  idx);
 938                 RETURN(-EOVERFLOW);
 939         }
 940         if (test_and_set_bit(idx, tgt->lut_client_bitmap)) {
 941                 idx = find_next_zero_bit(tgt->lut_client_bitmap,
 942                                              LR_MAX_CLIENTS, idx);
 943                 goto repeat;
 944         }
 945
 946         ted->ted_lr_idx = idx;
 947         ted->ted_lr_off = tgt->lut_lsd.lsd_client_start +
 948                           idx * tgt->lut_lsd.lsd_client_size;
 949
 950         LASSERTF(ted->ted_lr_off > 0, "ted_lr_off = %llu\n", ted->ted_lr_off);
 951
 952         if (tgt_is_multimodrpcs_client(exp)) {
 953                 /* Set MULTI RPCS incompatibility flag to prevent previous
 954                  * Lustre versions to mount a target with reply_data file */
 955                 atomic_inc(&tgt->lut_num_clients);
 956                 if (!(tgt->lut_lsd.lsd_feature_incompat &
 957                       OBD_INCOMPAT_MULTI_RPCS)) {
 958                         tgt->lut_lsd.lsd_feature_incompat |=
 959                                                         OBD_INCOMPAT_MULTI_RPCS;
 960                         rc = tgt_server_data_update(env, tgt, 1);
 961                         if (rc < 0) {
 962                                 CERROR("%s: unable to set MULTI RPCS "
 963                                        "incompatibility flag\n",
 964                                        exp->exp_obd->obd_name);
 965                                 RETURN(rc);
 966                         }
 967                 }
 968
 969                 /* assign client slot generation */
 970                 ted->ted_lcd->lcd_generation =
 971                                 atomic_inc_return(&tgt->lut_client_generation);
 972         } else {
 973                 ted->ted_lcd->lcd_generation = 0;
 974         }
 975
 976         CDEBUG(D_INFO, "%s: new client at index %d (%llu) with UUID '%s' "
 977                "generation %d\n",
 978                tgt->lut_obd->obd_name, ted->ted_lr_idx, ted->ted_lr_off,
 979                ted->ted_lcd->lcd_uuid, ted->ted_lcd->lcd_generation);
 980
 981         if (OBD_FAIL_CHECK(OBD_FAIL_TGT_CLIENT_ADD))
 982                 RETURN(-ENOSPC);
 983
 984         rc = tgt_client_data_update(env, exp);
 985         if (rc)
 986                 CERROR("%s: Failed to write client lcd at idx %d, rc %d\n",
 987                        tgt->lut_obd->obd_name, idx, rc);
 988
 989         RETURN(rc);
 990 }
 991 EXPORT_SYMBOL(tgt_client_new);
 992
 993 /* Add an existing client to the MDS in-memory state based on
 994  * a client that was previously found in the last_rcvd file and
 995  * already has an assigned slot (idx >= 0).
 996  *
 997  * It should not be possible to fail adding an existing client - otherwise
 998  * mdt_init_server_data() callsite needs to be fixed.
 999  */
1000 int tgt_client_add(const struct lu_env *env,  struct obd_export *exp, int idx)
1001 {
1002         struct tg_export_data   *ted = &exp->exp_target_data;
1003         struct lu_target        *tgt = class_exp2tgt(exp);
1004
1005         ENTRY;
1006
1007         LASSERT(tgt && tgt->lut_client_bitmap != NULL);
1008         LASSERTF(idx >= 0, "%d\n", idx);
1009
1010         if (!strcmp(ted->ted_lcd->lcd_uuid, tgt->lut_obd->obd_uuid.uuid) ||
1011             exp_connect_flags(exp) & OBD_CONNECT_LIGHTWEIGHT)
1012                 RETURN(0);
1013
1014         if (test_and_set_bit(idx, tgt->lut_client_bitmap)) {
1015                 CERROR("%s: client %d: bit already set in bitmap!!\n",
1016                        tgt->lut_obd->obd_name,  idx);
1017                 LBUG();
1018         }
1019         atomic_inc(&tgt->lut_num_clients);
1020
1021         CDEBUG(D_INFO, "%s: client at idx %d with UUID '%s' added, "
1022                "generation %d\n",
1023                tgt->lut_obd->obd_name, idx, ted->ted_lcd->lcd_uuid,
1024                ted->ted_lcd->lcd_generation);
1025
1026         ted->ted_lr_idx = idx;
1027         ted->ted_lr_off = tgt->lut_lsd.lsd_client_start +
1028                           idx * tgt->lut_lsd.lsd_client_size;
1029
1030         mutex_init(&ted->ted_lcd_lock);
1031
1032         LASSERTF(ted->ted_lr_off > 0, "ted_lr_off = %llu\n", ted->ted_lr_off);
1033
1034         RETURN(0);
1035 }
1036
1037 int tgt_client_del(const struct lu_env *env, struct obd_export *exp)
1038 {
1039         struct tg_export_data   *ted = &exp->exp_target_data;
1040         struct lu_target        *tgt = class_exp2tgt(exp);
1041         int                      rc;
1042
1043         ENTRY;
1044
1045         LASSERT(ted->ted_lcd);
1046
1047         if (unlikely(tgt == NULL)) {
1048                 CDEBUG(D_ERROR, "%s: No target for connected export\n",
1049                        class_exp2obd(exp)->obd_name);
1050                 RETURN(-EINVAL);
1051         }
1052
1053         /* XXX if lcd_uuid were a real obd_uuid, I could use obd_uuid_equals */
1054         if (!strcmp((char *)ted->ted_lcd->lcd_uuid,
1055                     (char *)tgt->lut_obd->obd_uuid.uuid) ||
1056             exp_connect_flags(exp) & OBD_CONNECT_LIGHTWEIGHT)
1057                 RETURN(0);
1058
1059         /* Slot may be not yet assigned, use case is race between Client
1060          * reconnect and forced eviction */
1061         if (ted->ted_lr_idx < 0) {
1062                 CWARN("%s: client with UUID '%s' not in bitmap\n",
1063                       tgt->lut_obd->obd_name, ted->ted_lcd->lcd_uuid);
1064                 RETURN(0);
1065         }
1066
1067         CDEBUG(D_INFO, "%s: del client at idx %u, off %lld, UUID '%s'\n",
1068                tgt->lut_obd->obd_name, ted->ted_lr_idx, ted->ted_lr_off,
1069                ted->ted_lcd->lcd_uuid);
1070
1071         /* Clear the bit _after_ zeroing out the client so we don't
1072            race with filter_client_add and zero out new clients.*/
1073         if (!test_bit(ted->ted_lr_idx, tgt->lut_client_bitmap)) {
1074                 CERROR("%s: client %u: bit already clear in bitmap!!\n",
1075                        tgt->lut_obd->obd_name, ted->ted_lr_idx);
1076                 LBUG();
1077         }
1078
1079         /* Do not erase record for recoverable client. */
1080         if (exp->exp_flags & OBD_OPT_FAILOVER)
1081                 RETURN(0);
1082
1083         if (OBD_FAIL_CHECK(OBD_FAIL_TGT_CLIENT_DEL))
1084                 RETURN(0);
1085
1086         /* Make sure the server's last_transno is up to date.
1087          * This should be done before zeroing client slot so last_transno will
1088          * be in server data or in client data in case of failure */
1089         rc = tgt_server_data_update(env, tgt, 0);
1090         if (rc != 0) {
1091                 CERROR("%s: failed to update server data, skip client %s "
1092                        "zeroing, rc %d\n", tgt->lut_obd->obd_name,
1093                        ted->ted_lcd->lcd_uuid, rc);
1094                 RETURN(rc);
1095         }
1096
1097         memset(ted->ted_lcd->lcd_uuid, 0, sizeof ted->ted_lcd->lcd_uuid);
1098         rc = tgt_client_data_update(env, exp);
1099
1100         CDEBUG(rc == 0 ? D_INFO : D_ERROR,
1101                "%s: zeroing out client %s at idx %u (%llu), rc %d\n",
1102                tgt->lut_obd->obd_name, ted->ted_lcd->lcd_uuid,
1103                ted->ted_lr_idx, ted->ted_lr_off, rc);
1104         RETURN(rc);
1105 }
1106 EXPORT_SYMBOL(tgt_client_del);
1107
1108 int tgt_add_reply_data(const struct lu_env *env, struct lu_target *tgt,
1109                        struct tg_export_data *ted, struct tg_reply_data *trd,
1110                        struct thandle *th, bool update_lrd_file)
1111 {
1112         struct lsd_reply_data   *lrd;
1113         int     i;
1114
1115         lrd = &trd->trd_reply;
1116         /* update export last transno */
1117         mutex_lock(&ted->ted_lcd_lock);
1118         if (lrd->lrd_transno > ted->ted_lcd->lcd_last_transno)
1119                 ted->ted_lcd->lcd_last_transno = lrd->lrd_transno;
1120         mutex_unlock(&ted->ted_lcd_lock);
1121
1122         /* find a empty slot */
1123         i = tgt_find_free_reply_slot(tgt);
1124         if (unlikely(i < 0)) {
1125                 CERROR("%s: couldn't find a slot for reply data: "
1126                        "rc = %d\n", tgt_name(tgt), i);
1127                 RETURN(i);
1128         }
1129         trd->trd_index = i;
1130
1131         if (update_lrd_file) {
1132                 loff_t  off;
1133                 int     rc;
1134
1135                 /* write reply data to disk */
1136                 off = sizeof(struct lsd_reply_header) + sizeof(*lrd) * i;
1137                 rc = tgt_reply_data_write(env, tgt, lrd, off, th);
1138                 if (unlikely(rc != 0)) {
1139                         CERROR("%s: can't update %s file: rc = %d\n",
1140                                tgt_name(tgt), REPLY_DATA, rc);
1141                         RETURN(rc);
1142                 }
1143         }
1144         /* add reply data to target export's reply list */
1145         mutex_lock(&ted->ted_lcd_lock);
1146         list_add(&trd->trd_list, &ted->ted_reply_list);
1147         ted->ted_reply_cnt++;
1148         if (ted->ted_reply_cnt > ted->ted_reply_max)
1149                 ted->ted_reply_max = ted->ted_reply_cnt;
1150         mutex_unlock(&ted->ted_lcd_lock);
1151
1152         CDEBUG(D_TRACE, "add reply %p: xid %llu, transno %llu, "
1153                "tag %hu, client gen %u, slot idx %d\n",
1154                trd, lrd->lrd_xid, lrd->lrd_transno,
1155                trd->trd_tag, lrd->lrd_client_gen, i);
1156         RETURN(0);
1157 }
1158 EXPORT_SYMBOL(tgt_add_reply_data);
1159
1160 /*
1161  * last_rcvd & last_committed update callbacks
1162  */
1163 static int tgt_last_rcvd_update(const struct lu_env *env, struct lu_target *tgt,
1164                                 struct dt_object *obj, __u64 opdata,
1165                                 struct thandle *th, struct ptlrpc_request *req)
1166 {
1167         struct tgt_thread_info  *tti = tgt_th_info(env);
1168         struct tgt_session_info *tsi = tgt_ses_info(env);
1169         struct obd_export       *exp = tsi->tsi_exp;
1170         struct tg_export_data   *ted;
1171         __u64                   *transno_p;
1172         int                      rc = 0;
1173         bool                     lw_client;
1174
1175         ENTRY;
1176
1177
1178         LASSERT(exp != NULL);
1179         ted = &exp->exp_target_data;
1180
1181         lw_client = exp_connect_flags(exp) & OBD_CONNECT_LIGHTWEIGHT;
1182         if (ted->ted_lr_idx < 0 && !lw_client)
1183                 /* ofd connect may cause transaction before export has
1184                  * last_rcvd slot */
1185                 RETURN(0);
1186
1187         if (req != NULL)
1188                 tti->tti_transno = lustre_msg_get_transno(req->rq_reqmsg);
1189         else
1190                 /* From update replay, tti_transno should be set already */
1191                 LASSERT(tti->tti_transno != 0);
1192
1193         spin_lock(&tgt->lut_translock);
1194         if (th->th_result != 0) {
1195                 if (tti->tti_transno != 0) {
1196                         CERROR("%s: replay transno %llu failed: rc = %d\n",
1197                                tgt_name(tgt), tti->tti_transno, th->th_result);
1198                 }
1199         } else if (tti->tti_transno == 0) {
1200                 tti->tti_transno = ++tgt->lut_last_transno;
1201         } else {
1202                 /* should be replay */
1203                 if (tti->tti_transno > tgt->lut_last_transno)
1204                         tgt->lut_last_transno = tti->tti_transno;
1205         }
1206         spin_unlock(&tgt->lut_translock);
1207
1208         /** VBR: set new versions */
1209         if (th->th_result == 0 && obj != NULL) {
1210                 struct dt_object *dto = dt_object_locate(obj, th->th_dev);
1211                 dt_version_set(env, dto, tti->tti_transno, th);
1212         }
1213
1214         /* filling reply data */
1215         CDEBUG(D_INODE, "transno = %llu, last_committed = %llu\n",
1216                tti->tti_transno, tgt->lut_obd->obd_last_committed);
1217
1218         if (req != NULL) {
1219                 req->rq_transno = tti->tti_transno;
1220                 lustre_msg_set_transno(req->rq_repmsg, tti->tti_transno);
1221         }
1222
1223         /* if can't add callback, do sync write */
1224         th->th_sync |= !!tgt_last_commit_cb_add(th, tgt, exp, tti->tti_transno);
1225
1226         if (lw_client) {
1227                 /* All operations performed by LW clients are synchronous and
1228                  * we store the committed transno in the last_rcvd header */
1229                 spin_lock(&tgt->lut_translock);
1230                 if (tti->tti_transno > tgt->lut_lsd.lsd_last_transno) {
1231                         tgt->lut_lsd.lsd_last_transno = tti->tti_transno;
1232                         spin_unlock(&tgt->lut_translock);
1233                         /* Although lightweight (LW) connections have no slot
1234                          * in the last_rcvd, we still want to maintain
1235                          * the in-memory lsd_client_data structure in order to
1236                          * properly handle reply reconstruction. */
1237                         rc = tgt_server_data_write(env, tgt, th);
1238                 } else {
1239                         spin_unlock(&tgt->lut_translock);
1240                 }
1241         } else if (ted->ted_lr_off == 0) {
1242                 CERROR("%s: client idx %d has offset %lld\n",
1243                        tgt_name(tgt), ted->ted_lr_idx, ted->ted_lr_off);
1244                 RETURN(-EINVAL);
1245         }
1246
1247         /* Target that supports multiple reply data */
1248         if (tgt_is_multimodrpcs_client(exp)) {
1249                 struct tg_reply_data    *trd;
1250                 struct lsd_reply_data   *lrd;
1251                 __u64                   *pre_versions;
1252                 bool                    write_update;
1253
1254                 OBD_ALLOC_PTR(trd);
1255                 if (unlikely(trd == NULL))
1256                         RETURN(-ENOMEM);
1257
1258                 /* fill reply data information */
1259                 lrd = &trd->trd_reply;
1260                 lrd->lrd_transno = tti->tti_transno;
1261                 if (req != NULL) {
1262                         lrd->lrd_xid = req->rq_xid;
1263                         trd->trd_tag = lustre_msg_get_tag(req->rq_reqmsg);
1264                         pre_versions = lustre_msg_get_versions(req->rq_repmsg);
1265                         lrd->lrd_result = th->th_result;
1266                         lrd->lrd_client_gen = ted->ted_lcd->lcd_generation;
1267                         write_update = true;
1268                 } else {
1269                         LASSERT(tsi->tsi_xid != 0);
1270                         lrd->lrd_xid = tsi->tsi_xid;
1271                         lrd->lrd_result = tsi->tsi_result;
1272                         lrd->lrd_client_gen = tsi->tsi_client_gen;
1273                         trd->trd_tag = 0;
1274                         pre_versions = NULL;
1275                         write_update = false;
1276                 }
1277
1278                 lrd->lrd_data = opdata;
1279                 if (pre_versions) {
1280                         trd->trd_pre_versions[0] = pre_versions[0];
1281                         trd->trd_pre_versions[1] = pre_versions[1];
1282                         trd->trd_pre_versions[2] = pre_versions[2];
1283                         trd->trd_pre_versions[3] = pre_versions[3];
1284                 }
1285
1286                 rc = tgt_add_reply_data(env, tgt, ted, trd, th, write_update);
1287                 if (rc < 0)
1288                         OBD_FREE_PTR(trd);
1289                 return rc;
1290         }
1291
1292         /* Enough for update replay, let's return */
1293         if (req == NULL)
1294                 RETURN(rc);
1295
1296         mutex_lock(&ted->ted_lcd_lock);
1297         LASSERT(ergo(tti->tti_transno == 0, th->th_result != 0));
1298         if (lustre_msg_get_opc(req->rq_reqmsg) == MDS_CLOSE) {
1299                 transno_p = &ted->ted_lcd->lcd_last_close_transno;
1300                 ted->ted_lcd->lcd_last_close_xid = req->rq_xid;
1301                 ted->ted_lcd->lcd_last_close_result = th->th_result;
1302         } else {
1303                 /* VBR: save versions in last_rcvd for reconstruct. */
1304                 __u64 *pre_versions = lustre_msg_get_versions(req->rq_repmsg);
1305
1306                 if (pre_versions) {
1307                         ted->ted_lcd->lcd_pre_versions[0] = pre_versions[0];
1308                         ted->ted_lcd->lcd_pre_versions[1] = pre_versions[1];
1309                         ted->ted_lcd->lcd_pre_versions[2] = pre_versions[2];
1310                         ted->ted_lcd->lcd_pre_versions[3] = pre_versions[3];
1311                 }
1312                 transno_p = &ted->ted_lcd->lcd_last_transno;
1313                 ted->ted_lcd->lcd_last_xid = req->rq_xid;
1314                 ted->ted_lcd->lcd_last_result = th->th_result;
1315                 /* XXX: lcd_last_data is __u32 but intent_dispostion is __u64,
1316                  * see struct ldlm_reply->lock_policy_res1; */
1317                 ted->ted_lcd->lcd_last_data = opdata;
1318         }
1319
1320         /* Update transno in slot only if non-zero number, i.e. no errors */
1321         if (likely(tti->tti_transno != 0)) {
1322                 /* Don't overwrite bigger transaction number with lower one.
1323                  * That is not sign of problem in all cases, but in any case
1324                  * this value should be monotonically increased only. */
1325                 if (*transno_p > tti->tti_transno) {
1326                         if (!tgt->lut_no_reconstruct) {
1327                                 CERROR("%s: trying to overwrite bigger transno:"
1328                                        "on-disk: %llu, new: %llu replay: "
1329                                        "%d. See LU-617.\n", tgt_name(tgt),
1330                                        *transno_p, tti->tti_transno,
1331                                        req_is_replay(req));
1332                                 if (req_is_replay(req)) {
1333                                         spin_lock(&req->rq_export->exp_lock);
1334                                         req->rq_export->exp_vbr_failed = 1;
1335                                         spin_unlock(&req->rq_export->exp_lock);
1336                                 }
1337                                 mutex_unlock(&ted->ted_lcd_lock);
1338                                 RETURN(req_is_replay(req) ? -EOVERFLOW : 0);
1339                         }
1340                 } else {
1341                         *transno_p = tti->tti_transno;
1342                 }
1343         }
1344
1345         if (!lw_client) {
1346                 tti->tti_off = ted->ted_lr_off;
1347                 if (CFS_FAIL_CHECK(OBD_FAIL_TGT_RCVD_EIO))
1348                         rc = -EIO;
1349                 else
1350                         rc = tgt_client_data_write(env, tgt, ted->ted_lcd,
1351                                                    &tti->tti_off, th);
1352                 if (rc < 0) {
1353                         mutex_unlock(&ted->ted_lcd_lock);
1354                         RETURN(rc);
1355                 }
1356         }
1357         mutex_unlock(&ted->ted_lcd_lock);
1358         RETURN(rc);
1359 }
1360
1361 /*
1362  * last_rcvd update for echo client simulation.
1363  * It updates last_rcvd client slot and version of object in
1364  * simple way but with all locks to simulate all drawbacks
1365  */
1366 static int tgt_last_rcvd_update_echo(const struct lu_env *env,
1367                                      struct lu_target *tgt,
1368                                      struct dt_object *obj,
1369                                      struct thandle *th,
1370                                      struct obd_export *exp)
1371 {
1372         struct tgt_thread_info  *tti = tgt_th_info(env);
1373         struct tg_export_data   *ted = &exp->exp_target_data;
1374         int                      rc = 0;
1375
1376         ENTRY;
1377
1378         tti->tti_transno = 0;
1379
1380         spin_lock(&tgt->lut_translock);
1381         if (th->th_result == 0)
1382                 tti->tti_transno = ++tgt->lut_last_transno;
1383         spin_unlock(&tgt->lut_translock);
1384
1385         /** VBR: set new versions */
1386         if (th->th_result == 0 && obj != NULL)
1387                 dt_version_set(env, obj, tti->tti_transno, th);
1388
1389         /* if can't add callback, do sync write */
1390         th->th_sync |= !!tgt_last_commit_cb_add(th, tgt, exp,
1391                                                 tti->tti_transno);
1392
1393         LASSERT(ted->ted_lr_off > 0);
1394
1395         mutex_lock(&ted->ted_lcd_lock);
1396         LASSERT(ergo(tti->tti_transno == 0, th->th_result != 0));
1397         ted->ted_lcd->lcd_last_transno = tti->tti_transno;
1398         ted->ted_lcd->lcd_last_result = th->th_result;
1399
1400         tti->tti_off = ted->ted_lr_off;
1401         rc = tgt_client_data_write(env, tgt, ted->ted_lcd, &tti->tti_off, th);
1402         mutex_unlock(&ted->ted_lcd_lock);
1403         RETURN(rc);
1404 }
1405
1406 static int tgt_clients_data_init(const struct lu_env *env,
1407                                  struct lu_target *tgt,
1408                                  unsigned long last_size)
1409 {
1410         struct obd_device       *obd = tgt->lut_obd;
1411         struct lr_server_data   *lsd = &tgt->lut_lsd;
1412         struct lsd_client_data  *lcd = NULL;
1413         struct tg_export_data   *ted;
1414         int                      cl_idx;
1415         int                      rc = 0;
1416         loff_t                   off = lsd->lsd_client_start;
1417         __u32                    generation = 0;
1418         struct cfs_hash         *hash = NULL;
1419
1420         ENTRY;
1421
1422         CLASSERT(offsetof(struct lsd_client_data, lcd_padding) +
1423                  sizeof(lcd->lcd_padding) == LR_CLIENT_SIZE);
1424
1425         OBD_ALLOC_PTR(lcd);
1426         if (lcd == NULL)
1427                 RETURN(-ENOMEM);
1428
1429         hash = cfs_hash_getref(tgt->lut_obd->obd_gen_hash);
1430         if (hash == NULL)
1431                 GOTO(err_out, rc = -ENODEV);
1432
1433         for (cl_idx = 0; off < last_size; cl_idx++) {
1434                 struct obd_export       *exp;
1435                 __u64                    last_transno;
1436
1437                 /* Don't assume off is incremented properly by
1438                  * read_record(), in case sizeof(*lcd)
1439                  * isn't the same as fsd->lsd_client_size.  */
1440                 off = lsd->lsd_client_start + cl_idx * lsd->lsd_client_size;
1441                 rc = tgt_client_data_read(env, tgt, lcd, &off, cl_idx);
1442                 if (rc) {
1443                         CERROR("%s: error reading last_rcvd %s idx %d off "
1444                                "%llu: rc = %d\n", tgt_name(tgt), LAST_RCVD,
1445                                cl_idx, off, rc);
1446                         rc = 0;
1447                         break; /* read error shouldn't cause startup to fail */
1448                 }
1449
1450                 if (lcd->lcd_uuid[0] == '\0') {
1451                         CDEBUG(D_INFO, "skipping zeroed client at offset %d\n",
1452                                cl_idx);
1453                         continue;
1454                 }
1455
1456                 last_transno = lcd_last_transno(lcd);
1457
1458                 /* These exports are cleaned up by disconnect, so they
1459                  * need to be set up like real exports as connect does.
1460                  */
1461                 CDEBUG(D_HA, "RCVRNG CLIENT uuid: %s idx: %d lr: %llu"
1462                        " srv lr: %llu lx: %llu gen %u\n", lcd->lcd_uuid,
1463                        cl_idx, last_transno, lsd->lsd_last_transno,
1464                        lcd_last_xid(lcd), lcd->lcd_generation);
1465
1466                 exp = class_new_export(obd, (struct obd_uuid *)lcd->lcd_uuid);
1467                 if (IS_ERR(exp)) {
1468                         if (PTR_ERR(exp) == -EALREADY) {
1469                                 /* export already exists, zero out this one */
1470                                 CERROR("%s: Duplicate export %s!\n",
1471                                        tgt_name(tgt), lcd->lcd_uuid);
1472                                 continue;
1473                         }
1474                         GOTO(err_out, rc = PTR_ERR(exp));
1475                 }
1476
1477                 ted = &exp->exp_target_data;
1478                 *ted->ted_lcd = *lcd;
1479
1480                 rc = tgt_client_add(env, exp, cl_idx);
1481                 LASSERTF(rc == 0, "rc = %d\n", rc); /* can't fail existing */
1482                 /* VBR: set export last committed version */
1483                 exp->exp_last_committed = last_transno;
1484                 spin_lock(&exp->exp_lock);
1485                 exp->exp_connecting = 0;
1486                 exp->exp_in_recovery = 0;
1487                 spin_unlock(&exp->exp_lock);
1488                 obd->obd_max_recoverable_clients++;
1489
1490                 if (tgt->lut_lsd.lsd_feature_incompat &
1491                     OBD_INCOMPAT_MULTI_RPCS &&
1492                     lcd->lcd_generation != 0) {
1493                         /* compute the highest valid client generation */
1494                         generation = max(generation, lcd->lcd_generation);
1495                         /* fill client_generation <-> export hash table */
1496                         rc = cfs_hash_add_unique(hash, &lcd->lcd_generation,
1497                                                  &exp->exp_gen_hash);
1498                         if (rc != 0) {
1499                                 CERROR("%s: duplicate export for client "
1500                                        "generation %u\n",
1501                                        tgt_name(tgt), lcd->lcd_generation);
1502                                 class_export_put(exp);
1503                                 GOTO(err_out, rc);
1504                         }
1505                 }
1506
1507                 class_export_put(exp);
1508
1509                 rc = rev_import_init(exp);
1510                 if (rc != 0) {
1511                         class_unlink_export(exp);
1512                         GOTO(err_out, rc);
1513                 }
1514
1515                 /* Need to check last_rcvd even for duplicated exports. */
1516                 CDEBUG(D_OTHER, "client at idx %d has last_transno = %llu\n",
1517                        cl_idx, last_transno);
1518
1519                 spin_lock(&tgt->lut_translock);
1520                 tgt->lut_last_transno = max(last_transno,
1521                                             tgt->lut_last_transno);
1522                 spin_unlock(&tgt->lut_translock);
1523         }
1524
1525         /* record highest valid client generation */
1526         atomic_set(&tgt->lut_client_generation, generation);
1527
1528 err_out:
1529         if (hash != NULL)
1530                 cfs_hash_putref(hash);
1531         OBD_FREE_PTR(lcd);
1532         RETURN(rc);
1533 }
1534
1535 struct server_compat_data {
1536         __u32 rocompat;
1537         __u32 incompat;
1538         __u32 rocinit;
1539         __u32 incinit;
1540 };
1541
1542 static struct server_compat_data tgt_scd[] = {
1543         [LDD_F_SV_TYPE_MDT] = {
1544                 .rocompat = OBD_ROCOMPAT_LOVOBJID,
1545                 .incompat = OBD_INCOMPAT_MDT | OBD_INCOMPAT_COMMON_LR |
1546                             OBD_INCOMPAT_FID | OBD_INCOMPAT_IAM_DIR |
1547                             OBD_INCOMPAT_LMM_VER | OBD_INCOMPAT_MULTI_OI |
1548                             OBD_INCOMPAT_MULTI_RPCS,
1549                 .rocinit = OBD_ROCOMPAT_LOVOBJID,
1550                 .incinit = OBD_INCOMPAT_MDT | OBD_INCOMPAT_COMMON_LR |
1551                            OBD_INCOMPAT_MULTI_OI,
1552         },
1553         [LDD_F_SV_TYPE_OST] = {
1554                 .rocompat = OBD_ROCOMPAT_IDX_IN_IDIF,
1555                 .incompat = OBD_INCOMPAT_OST | OBD_INCOMPAT_COMMON_LR |
1556                             OBD_INCOMPAT_FID,
1557                 .rocinit = OBD_ROCOMPAT_IDX_IN_IDIF,
1558                 .incinit = OBD_INCOMPAT_OST | OBD_INCOMPAT_COMMON_LR,
1559         }
1560 };
1561
1562 int tgt_server_data_init(const struct lu_env *env, struct lu_target *tgt)
1563 {
1564         struct tgt_thread_info          *tti = tgt_th_info(env);
1565         struct lr_server_data           *lsd = &tgt->lut_lsd;
1566         unsigned long                    last_rcvd_size;
1567         __u32                            index;
1568         int                              rc, type;
1569
1570         rc = dt_attr_get(env, tgt->lut_last_rcvd, &tti->tti_attr);
1571         if (rc)
1572                 RETURN(rc);
1573
1574         last_rcvd_size = (unsigned long)tti->tti_attr.la_size;
1575
1576         /* ensure padding in the struct is the correct size */
1577         CLASSERT(offsetof(struct lr_server_data, lsd_padding) +
1578                  sizeof(lsd->lsd_padding) == LR_SERVER_SIZE);
1579
1580         rc = server_name2index(tgt_name(tgt), &index, NULL);
1581         if (rc < 0) {
1582                 CERROR("%s: Can not get index from name: rc = %d\n",
1583                        tgt_name(tgt), rc);
1584                 RETURN(rc);
1585         }
1586         /* server_name2index() returns type */
1587         type = rc;
1588         if (type != LDD_F_SV_TYPE_MDT && type != LDD_F_SV_TYPE_OST) {
1589                 CERROR("%s: unknown target type %x\n", tgt_name(tgt), type);
1590                 RETURN(-EINVAL);
1591         }
1592
1593         /* last_rcvd on OST doesn't provide reconstruct support because there
1594          * may be up to 8 in-flight write requests per single slot in
1595          * last_rcvd client data
1596          */
1597         tgt->lut_no_reconstruct = (type == LDD_F_SV_TYPE_OST);
1598
1599         if (last_rcvd_size == 0) {
1600                 LCONSOLE_WARN("%s: new disk, initializing\n", tgt_name(tgt));
1601
1602                 memcpy(lsd->lsd_uuid, tgt->lut_obd->obd_uuid.uuid,
1603                        sizeof(lsd->lsd_uuid));
1604                 lsd->lsd_last_transno = 0;
1605                 lsd->lsd_mount_count = 0;
1606                 lsd->lsd_server_size = LR_SERVER_SIZE;
1607                 lsd->lsd_client_start = LR_CLIENT_START;
1608                 lsd->lsd_client_size = LR_CLIENT_SIZE;
1609                 lsd->lsd_subdir_count = OBJ_SUBDIR_COUNT;
1610                 lsd->lsd_osd_index = index;
1611                 lsd->lsd_feature_rocompat = tgt_scd[type].rocinit;
1612                 lsd->lsd_feature_incompat = tgt_scd[type].incinit;
1613         } else {
1614                 rc = tgt_server_data_read(env, tgt);
1615                 if (rc) {
1616                         CERROR("%s: error reading LAST_RCVD: rc= %d\n",
1617                                tgt_name(tgt), rc);
1618                         RETURN(rc);
1619                 }
1620                 if (strcmp(lsd->lsd_uuid, tgt->lut_obd->obd_uuid.uuid)) {
1621                         LCONSOLE_ERROR_MSG(0x157, "Trying to start OBD %s "
1622                                            "using the wrong disk %s. Were the"
1623                                            " /dev/ assignments rearranged?\n",
1624                                            tgt->lut_obd->obd_uuid.uuid,
1625                                            lsd->lsd_uuid);
1626                         RETURN(-EINVAL);
1627                 }
1628
1629                 if (lsd->lsd_osd_index != index) {
1630                         LCONSOLE_ERROR_MSG(0x157, "%s: index %d in last rcvd "
1631                                            "is different with the index %d in"
1632                                            "config log, It might be disk"
1633                                            "corruption!\n", tgt_name(tgt),
1634                                            lsd->lsd_osd_index, index);
1635                         RETURN(-EINVAL);
1636                 }
1637         }
1638
1639         if (lsd->lsd_feature_incompat & ~tgt_scd[type].incompat) {
1640                 CERROR("%s: unsupported incompat filesystem feature(s) %x\n",
1641                        tgt_name(tgt),
1642                        lsd->lsd_feature_incompat & ~tgt_scd[type].incompat);
1643                 RETURN(-EINVAL);
1644         }
1645
1646         if (type == LDD_F_SV_TYPE_MDT)
1647                 lsd->lsd_feature_incompat |= OBD_INCOMPAT_FID;
1648
1649         if (lsd->lsd_feature_rocompat & ~tgt_scd[type].rocompat) {
1650                 CERROR("%s: unsupported read-only filesystem feature(s) %x\n",
1651                        tgt_name(tgt),
1652                        lsd->lsd_feature_rocompat & ~tgt_scd[type].rocompat);
1653                 RETURN(-EINVAL);
1654         }
1655         /** Interop: evict all clients at first boot with 1.8 last_rcvd */
1656         if (type == LDD_F_SV_TYPE_MDT &&
1657             !(lsd->lsd_feature_compat & OBD_COMPAT_20)) {
1658                 if (last_rcvd_size > lsd->lsd_client_start) {
1659                         LCONSOLE_WARN("%s: mounting at first time on 1.8 FS, "
1660                                       "remove all clients for interop needs\n",
1661                                       tgt_name(tgt));
1662                         rc = tgt_truncate_last_rcvd(env, tgt,
1663                                                     lsd->lsd_client_start);
1664                         if (rc)
1665                                 RETURN(rc);
1666                         last_rcvd_size = lsd->lsd_client_start;
1667                 }
1668                 /** set 2.0 flag to upgrade/downgrade between 1.8 and 2.0 */
1669                 lsd->lsd_feature_compat |= OBD_COMPAT_20;
1670         }
1671
1672         spin_lock(&tgt->lut_translock);
1673         tgt->lut_last_transno = lsd->lsd_last_transno;
1674         spin_unlock(&tgt->lut_translock);
1675
1676         lsd->lsd_mount_count++;
1677
1678         CDEBUG(D_INODE, "=======,=BEGIN DUMPING LAST_RCVD========\n");
1679         CDEBUG(D_INODE, "%s: server last_transno: %llu\n",
1680                tgt_name(tgt), tgt->lut_last_transno);
1681         CDEBUG(D_INODE, "%s: server mount_count: %llu\n",
1682                tgt_name(tgt), lsd->lsd_mount_count);
1683         CDEBUG(D_INODE, "%s: server data size: %u\n",
1684                tgt_name(tgt), lsd->lsd_server_size);
1685         CDEBUG(D_INODE, "%s: per-client data start: %u\n",
1686                tgt_name(tgt), lsd->lsd_client_start);
1687         CDEBUG(D_INODE, "%s: per-client data size: %u\n",
1688                tgt_name(tgt), lsd->lsd_client_size);
1689         CDEBUG(D_INODE, "%s: last_rcvd size: %lu\n",
1690                tgt_name(tgt), last_rcvd_size);
1691         CDEBUG(D_INODE, "%s: server subdir_count: %u\n",
1692                tgt_name(tgt), lsd->lsd_subdir_count);
1693         CDEBUG(D_INODE, "%s: last_rcvd clients: %lu\n", tgt_name(tgt),
1694                last_rcvd_size <= lsd->lsd_client_start ? 0 :
1695                (last_rcvd_size - lsd->lsd_client_start) /
1696                 lsd->lsd_client_size);
1697         CDEBUG(D_INODE, "========END DUMPING LAST_RCVD========\n");
1698
1699         if (lsd->lsd_server_size == 0 || lsd->lsd_client_start == 0 ||
1700             lsd->lsd_client_size == 0) {
1701                 CERROR("%s: bad last_rcvd contents!\n", tgt_name(tgt));
1702                 RETURN(-EINVAL);
1703         }
1704
1705         if (!tgt->lut_obd->obd_replayable)
1706                 CWARN("%s: recovery support OFF\n", tgt_name(tgt));
1707
1708         rc = tgt_clients_data_init(env, tgt, last_rcvd_size);
1709         if (rc < 0)
1710                 GOTO(err_client, rc);
1711
1712         spin_lock(&tgt->lut_translock);
1713         /* obd_last_committed is used for compatibility
1714          * with other lustre recovery code */
1715         tgt->lut_obd->obd_last_committed = tgt->lut_last_transno;
1716         spin_unlock(&tgt->lut_translock);
1717
1718         tgt->lut_obd->u.obt.obt_mount_count = lsd->lsd_mount_count;
1719         tgt->lut_obd->u.obt.obt_instance = (__u32)lsd->lsd_mount_count;
1720
1721         /* save it, so mount count and last_transno is current */
1722         rc = tgt_server_data_update(env, tgt, 0);
1723         if (rc < 0)
1724                 GOTO(err_client, rc);
1725
1726         RETURN(0);
1727
1728 err_client:
1729         class_disconnect_exports(tgt->lut_obd);
1730         return rc;
1731 }
1732
1733 /* add credits for last_rcvd update */
1734 int tgt_txn_start_cb(const struct lu_env *env, struct thandle *th,
1735                      void *cookie)
1736 {
1737         struct lu_target        *tgt = cookie;
1738         struct tgt_session_info *tsi;
1739         struct tgt_thread_info  *tti = tgt_th_info(env);
1740         struct dt_object        *dto;
1741         int                      rc;
1742
1743         /* if there is no session, then this transaction is not result of
1744          * request processing but some local operation */
1745         if (env->le_ses == NULL)
1746                 return 0;
1747
1748         LASSERT(tgt->lut_last_rcvd);
1749         tsi = tgt_ses_info(env);
1750         /* OFD may start transaction without export assigned */
1751         if (tsi->tsi_exp == NULL)
1752                 return 0;
1753
1754         if (tgt_is_multimodrpcs_client(tsi->tsi_exp)) {
1755                 /*
1756                  * Use maximum possible file offset for declaration to ensure
1757                  * ZFS will reserve enough credits for a write anywhere in this
1758                  * file, since we don't know where in the file the write will be
1759                  * because a replay slot has not been assigned.  This should be
1760                  * replaced by dmu_tx_hold_append() when available.
1761                  */
1762                 tti->tti_buf.lb_buf = NULL;
1763                 tti->tti_buf.lb_len = sizeof(struct lsd_reply_data);
1764                 dto = dt_object_locate(tgt->lut_reply_data, th->th_dev);
1765                 rc = dt_declare_record_write(env, dto, &tti->tti_buf, -1, th);
1766                 if (rc)
1767                         return rc;
1768         } else {
1769                 dto = dt_object_locate(tgt->lut_last_rcvd, th->th_dev);
1770                 tti_buf_lcd(tti);
1771                 tti->tti_off = tsi->tsi_exp->exp_target_data.ted_lr_off;
1772                 rc = dt_declare_record_write(env, dto, &tti->tti_buf,
1773                                              tti->tti_off, th);
1774                 if (rc)
1775                         return rc;
1776         }
1777
1778         if (tsi->tsi_vbr_obj != NULL &&
1779             !lu_object_remote(&tsi->tsi_vbr_obj->do_lu)) {
1780                 dto = dt_object_locate(tsi->tsi_vbr_obj, th->th_dev);
1781                 rc = dt_declare_version_set(env, dto, th);
1782         }
1783
1784         return rc;
1785 }
1786
1787 /* Update last_rcvd records with latests transaction data */
1788 int tgt_txn_stop_cb(const struct lu_env *env, struct thandle *th,
1789                     void *cookie)
1790 {
1791         struct lu_target        *tgt = cookie;
1792         struct tgt_session_info *tsi;
1793         struct tgt_thread_info  *tti = tgt_th_info(env);
1794         struct dt_object        *obj = NULL;
1795         int                      rc;
1796         bool                     echo_client;
1797
1798         if (env->le_ses == NULL)
1799                 return 0;
1800
1801         tsi = tgt_ses_info(env);
1802         /* OFD may start transaction without export assigned */
1803         if (tsi->tsi_exp == NULL)
1804                 return 0;
1805
1806         echo_client = (tgt_ses_req(tsi) == NULL && tsi->tsi_xid == 0);
1807
1808         if (tti->tti_has_trans && !echo_client) {
1809                 if (tti->tti_mult_trans == 0) {
1810                         CDEBUG(D_HA, "More than one transaction %llu\n",
1811                                tti->tti_transno);
1812                         RETURN(0);
1813                 }
1814                 /* we need another transno to be assigned */
1815                 tti->tti_transno = 0;
1816         } else if (th->th_result == 0) {
1817                 tti->tti_has_trans = 1;
1818         }
1819
1820         if (tsi->tsi_vbr_obj != NULL &&
1821             !lu_object_remote(&tsi->tsi_vbr_obj->do_lu)) {
1822                 obj = tsi->tsi_vbr_obj;
1823         }
1824
1825         if (unlikely(echo_client)) /* echo client special case */
1826                 rc = tgt_last_rcvd_update_echo(env, tgt, obj, th,
1827                                                tsi->tsi_exp);
1828         else
1829                 rc = tgt_last_rcvd_update(env, tgt, obj, tsi->tsi_opdata, th,
1830                                           tgt_ses_req(tsi));
1831         return rc;
1832 }
1833
1834 int tgt_reply_data_init(const struct lu_env *env, struct lu_target *tgt)
1835 {
1836         struct tgt_thread_info  *tti = tgt_th_info(env);
1837         struct lsd_reply_data   *lrd = &tti->tti_lrd;
1838         unsigned long            reply_data_size;
1839         int                      rc;
1840         struct lsd_reply_header *lrh = NULL;
1841         struct lsd_client_data  *lcd = NULL;
1842         struct tg_reply_data    *trd = NULL;
1843         int                      idx;
1844         loff_t                   off;
1845         struct cfs_hash         *hash = NULL;
1846         struct obd_export       *exp;
1847         struct tg_export_data   *ted;
1848         int                      reply_data_recovered = 0;
1849
1850         rc = dt_attr_get(env, tgt->lut_reply_data, &tti->tti_attr);
1851         if (rc)
1852                 GOTO(out, rc);
1853         reply_data_size = (unsigned long)tti->tti_attr.la_size;
1854
1855         OBD_ALLOC_PTR(lrh);
1856         if (lrh == NULL)
1857                 GOTO(out, rc = -ENOMEM);
1858
1859         if (reply_data_size == 0) {
1860                 CDEBUG(D_INFO, "%s: new reply_data file, initializing\n",
1861                        tgt_name(tgt));
1862                 lrh->lrh_magic = LRH_MAGIC;
1863                 lrh->lrh_header_size = sizeof(struct lsd_reply_header);
1864                 lrh->lrh_reply_size = sizeof(struct lsd_reply_data);
1865                 rc = tgt_reply_header_write(env, tgt, lrh);
1866                 if (rc) {
1867                         CERROR("%s: error writing %s: rc = %d\n",
1868                                tgt_name(tgt), REPLY_DATA, rc);
1869                         GOTO(out, rc);
1870                 }
1871         } else {
1872                 rc = tgt_reply_header_read(env, tgt, lrh);
1873                 if (rc) {
1874                         CERROR("%s: error reading %s: rc = %d\n",
1875                                tgt_name(tgt), REPLY_DATA, rc);
1876                         GOTO(out, rc);
1877                 }
1878                 if (lrh->lrh_magic != LRH_MAGIC ||
1879                     lrh->lrh_header_size != sizeof(struct lsd_reply_header) ||
1880                     lrh->lrh_reply_size != sizeof(struct lsd_reply_data)) {
1881                         CERROR("%s: invalid header in %s\n",
1882                                tgt_name(tgt), REPLY_DATA);
1883                         GOTO(out, rc = -EINVAL);
1884                 }
1885
1886                 hash = cfs_hash_getref(tgt->lut_obd->obd_gen_hash);
1887                 if (hash == NULL)
1888                         GOTO(out, rc = -ENODEV);
1889
1890                 OBD_ALLOC_PTR(lcd);
1891                 if (lcd == NULL)
1892                         GOTO(out, rc = -ENOMEM);
1893
1894                 OBD_ALLOC_PTR(trd);
1895                 if (trd == NULL)
1896                         GOTO(out, rc = -ENOMEM);
1897
1898                 /* Load reply_data from disk */
1899                 for (idx = 0, off = sizeof(struct lsd_reply_header);
1900                      off < reply_data_size;
1901                      idx++, off += sizeof(struct lsd_reply_data)) {
1902                         rc = tgt_reply_data_read(env, tgt, lrd, off);
1903                         if (rc) {
1904                                 CERROR("%s: error reading %s: rc = %d\n",
1905                                        tgt_name(tgt), REPLY_DATA, rc);
1906                                 GOTO(out, rc);
1907                         }
1908
1909                         exp = cfs_hash_lookup(hash, &lrd->lrd_client_gen);
1910                         if (exp == NULL) {
1911                                 /* old reply data from a disconnected client */
1912                                 continue;
1913                         }
1914                         ted = &exp->exp_target_data;
1915                         mutex_lock(&ted->ted_lcd_lock);
1916
1917                         /* create in-memory reply_data and link it to
1918                          * target export's reply list */
1919                         rc = tgt_set_reply_slot(tgt, idx);
1920                         if (rc != 0) {
1921                                 mutex_unlock(&ted->ted_lcd_lock);
1922                                 GOTO(out, rc);
1923                         }
1924                         trd->trd_reply = *lrd;
1925                         trd->trd_pre_versions[0] = 0;
1926                         trd->trd_pre_versions[1] = 0;
1927                         trd->trd_pre_versions[2] = 0;
1928                         trd->trd_pre_versions[3] = 0;
1929                         trd->trd_index = idx;
1930                         trd->trd_tag = 0;
1931                         list_add(&trd->trd_list, &ted->ted_reply_list);
1932                         ted->ted_reply_cnt++;
1933                         if (ted->ted_reply_cnt > ted->ted_reply_max)
1934                                 ted->ted_reply_max = ted->ted_reply_cnt;
1935
1936                         CDEBUG(D_HA, "%s: restore reply %p: xid %llu, "
1937                                "transno %llu, client gen %u, slot idx %d\n",
1938                                tgt_name(tgt), trd, lrd->lrd_xid,
1939                                lrd->lrd_transno, lrd->lrd_client_gen,
1940                                trd->trd_index);
1941
1942                         /* update export last committed transation */
1943                         exp->exp_last_committed = max(exp->exp_last_committed,
1944                                                       lrd->lrd_transno);
1945
1946                         mutex_unlock(&ted->ted_lcd_lock);
1947                         class_export_put(exp);
1948
1949                         /* update target last committed transaction */
1950                         spin_lock(&tgt->lut_translock);
1951                         tgt->lut_last_transno = max(tgt->lut_last_transno,
1952                                                     lrd->lrd_transno);
1953                         spin_unlock(&tgt->lut_translock);
1954
1955                         reply_data_recovered++;
1956
1957                         OBD_ALLOC_PTR(trd);
1958                         if (trd == NULL)
1959                                 GOTO(out, rc = -ENOMEM);
1960                 }
1961                 CDEBUG(D_INFO, "%s: %d reply data have been recovered\n",
1962                        tgt_name(tgt), reply_data_recovered);
1963         }
1964
1965         spin_lock(&tgt->lut_translock);
1966         /* obd_last_committed is used for compatibility
1967          * with other lustre recovery code */
1968         tgt->lut_obd->obd_last_committed = tgt->lut_last_transno;
1969         spin_unlock(&tgt->lut_translock);
1970
1971         rc = 0;
1972
1973 out:
1974         if (hash != NULL)
1975                 cfs_hash_putref(hash);
1976         if (lcd != NULL)
1977                 OBD_FREE_PTR(lcd);
1978         if (trd != NULL)
1979                 OBD_FREE_PTR(trd);
1980         if (lrh != NULL)
1981                 OBD_FREE_PTR(lrh);
1982         return rc;
1983 }
1984
1985 struct tg_reply_data *tgt_lookup_reply_by_xid(struct tg_export_data *ted,
1986                                               __u64 xid)
1987 {
1988         struct tg_reply_data    *found = NULL;
1989         struct tg_reply_data    *reply;
1990
1991         mutex_lock(&ted->ted_lcd_lock);
1992         list_for_each_entry(reply, &ted->ted_reply_list, trd_list) {
1993                 if (reply->trd_reply.lrd_xid == xid) {
1994                         found = reply;
1995                         break;
1996                 }
1997         }
1998         mutex_unlock(&ted->ted_lcd_lock);
1999         return found;
2000 }
2001 EXPORT_SYMBOL(tgt_lookup_reply_by_xid);
2002
2003 /* Look for a reply data matching specified request @req
2004  * A copy is returned in @trd if the pointer is not NULL
2005  */
2006 bool tgt_lookup_reply(struct ptlrpc_request *req, struct tg_reply_data *trd)
2007 {
2008         struct tg_export_data   *ted = &req->rq_export->exp_target_data;
2009         struct tg_reply_data    *reply;
2010         bool                     found = false;
2011
2012         reply = tgt_lookup_reply_by_xid(ted, req->rq_xid);
2013         if (reply != NULL) {
2014                 found = true;
2015                 if (trd != NULL)
2016                         *trd = *reply;
2017         }
2018
2019         CDEBUG(D_TRACE, "%s: lookup reply xid %llu, found %d\n",
2020                tgt_name(class_exp2tgt(req->rq_export)), req->rq_xid,
2021                found ? 1 : 0);
2022
2023         return found;
2024 }
2025 EXPORT_SYMBOL(tgt_lookup_reply);
2026
2027 int tgt_handle_received_xid(struct obd_export *exp, __u64 rcvd_xid)
2028 {
2029         struct tg_export_data   *ted = &exp->exp_target_data;
2030         struct lu_target        *lut = class_exp2tgt(exp);
2031         struct tg_reply_data    *trd, *tmp;
2032
2033         mutex_lock(&ted->ted_lcd_lock);
2034         list_for_each_entry_safe(trd, tmp, &ted->ted_reply_list, trd_list) {
2035                 if (trd->trd_reply.lrd_xid > rcvd_xid)
2036                         continue;
2037                 ted->ted_release_xid++;
2038                 tgt_release_reply_data(lut, ted, trd);
2039         }
2040         mutex_unlock(&ted->ted_lcd_lock);
2041
2042         return 0;
2043 }
2044
2045 int tgt_handle_tag(struct obd_export *exp, __u16 tag)
2046 {
2047         struct tg_export_data   *ted = &exp->exp_target_data;
2048         struct lu_target        *lut = class_exp2tgt(exp);
2049         struct tg_reply_data    *trd, *tmp;
2050
2051         if (tag == 0)
2052                 return 0;
2053
2054         mutex_lock(&ted->ted_lcd_lock);
2055         list_for_each_entry_safe(trd, tmp, &ted->ted_reply_list, trd_list) {
2056                 if (trd->trd_tag != tag)
2057                         continue;
2058                 ted->ted_release_tag++;
2059                 tgt_release_reply_data(lut, ted, trd);
2060                 break;
2061         }
2062         mutex_unlock(&ted->ted_lcd_lock);
2063
2064         return 0;
2065 }
2066