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, 2017, Intel Corporation.
  27  */
  28 /*
  29  * This file is part of Lustre, http://www.lustre.org/
  30  *
  31  * Lustre Unified Target
  32  * These are common function to work with last_received file
  33  *
  34  * Author: Mikhail Pershin <mike.pershin@intel.com>
  35  */
  36 #include <obd.h>
  37 #include <obd_class.h>
  38 #include <lustre_fid.h>
  39
  40 #include "tgt_internal.h"
  41
  42 /** version recovery epoch */
  43 #define LR_EPOCH_BITS   32
  44
  45 /* Allocate a bitmap for a chunk of reply data slots */
  46 static int tgt_bitmap_chunk_alloc(struct lu_target *lut, int chunk)
  47 {
  48         unsigned long *bm;
  49
  50         OBD_ALLOC_LARGE(bm, BITS_TO_LONGS(LUT_REPLY_SLOTS_PER_CHUNK) *
  51                         sizeof(long));
  52         if (bm == NULL)
  53                 return -ENOMEM;
  54
  55         spin_lock(&lut->lut_client_bitmap_lock);
  56
  57         if (lut->lut_reply_bitmap[chunk] != NULL) {
  58                 /* someone else already allocated the bitmap for this chunk */
  59                 spin_unlock(&lut->lut_client_bitmap_lock);
  60                 OBD_FREE_LARGE(bm, BITS_TO_LONGS(LUT_REPLY_SLOTS_PER_CHUNK) *
  61                          sizeof(long));
  62                 return 0;
  63         }
  64
  65         lut->lut_reply_bitmap[chunk] = bm;
  66
  67         spin_unlock(&lut->lut_client_bitmap_lock);
  68
  69         return 0;
  70 }
  71
  72 /* Look for an available reply data slot in the bitmap
  73  * of the target @lut
  74  * Allocate bitmap chunk when first used
  75  * XXX algo could be improved if this routine limits performance
  76  */
  77 static int tgt_find_free_reply_slot(struct lu_target *lut)
  78 {
  79         unsigned long *bmp;
  80         int chunk = 0;
  81         int rc;
  82         int b;
  83
  84         for (chunk = 0; chunk < LUT_REPLY_SLOTS_MAX_CHUNKS; chunk++) {
  85                 /* allocate the bitmap chunk if necessary */
  86                 if (unlikely(lut->lut_reply_bitmap[chunk] == NULL)) {
  87                         rc = tgt_bitmap_chunk_alloc(lut, chunk);
  88                         if (rc != 0)
  89                                 return rc;
  90                 }
  91                 bmp = lut->lut_reply_bitmap[chunk];
  92
  93                 /* look for an available slot in this chunk */
  94                 do {
  95                         b = find_first_zero_bit(bmp, LUT_REPLY_SLOTS_PER_CHUNK);
  96                         if (b >= LUT_REPLY_SLOTS_PER_CHUNK)
  97                                 break;
  98
  99                         /* found one */
 100                         if (test_and_set_bit(b, bmp) == 0)
 101                                 return chunk * LUT_REPLY_SLOTS_PER_CHUNK + b;
 102                 } while (true);
 103         }
 104
 105         return -ENOSPC;
 106 }
 107
 108 /* Mark the reply data slot @idx 'used' in the corresponding bitmap chunk
 109  * of the target @lut
 110  * Allocate the bitmap chunk if necessary
 111  */
 112 static int tgt_set_reply_slot(struct lu_target *lut, int idx)
 113 {
 114         int chunk;
 115         int b;
 116         int rc;
 117
 118         chunk = idx / LUT_REPLY_SLOTS_PER_CHUNK;
 119         b = idx % LUT_REPLY_SLOTS_PER_CHUNK;
 120
 121         LASSERT(chunk < LUT_REPLY_SLOTS_MAX_CHUNKS);
 122         LASSERT(b < LUT_REPLY_SLOTS_PER_CHUNK);
 123
 124         /* allocate the bitmap chunk if necessary */
 125         if (unlikely(lut->lut_reply_bitmap[chunk] == NULL)) {
 126                 rc = tgt_bitmap_chunk_alloc(lut, chunk);
 127                 if (rc != 0)
 128                         return rc;
 129         }
 130
 131         /* mark the slot 'used' in this chunk */
 132         if (test_and_set_bit(b, lut->lut_reply_bitmap[chunk]) != 0) {
 133                 CERROR("%s: slot %d already set in bitmap\n",
 134                        tgt_name(lut), idx);
 135                 return -EALREADY;
 136         }
 137
 138         return 0;
 139 }
 140
 141
 142 /* Mark the reply data slot @idx 'unused' in the corresponding bitmap chunk
 143  * of the target @lut
 144  */
 145 static int tgt_clear_reply_slot(struct lu_target *lut, int idx)
 146 {
 147         int chunk;
 148         int b;
 149
 150         if (lut->lut_obd->obd_stopping)
 151                 /*
 152                  * in case of failover keep the bit set in order to
 153                  * avoid overwriting slots in reply_data which might
 154                  * be required by resent rpcs
 155                  */
 156                 return 0;
 157         chunk = idx / LUT_REPLY_SLOTS_PER_CHUNK;
 158         b = idx % LUT_REPLY_SLOTS_PER_CHUNK;
 159
 160         LASSERT(chunk < LUT_REPLY_SLOTS_MAX_CHUNKS);
 161         LASSERT(b < LUT_REPLY_SLOTS_PER_CHUNK);
 162
 163         if (lut->lut_reply_bitmap[chunk] == NULL) {
 164                 CERROR("%s: slot %d not allocated\n",
 165                        tgt_name(lut), idx);
 166                 return -ENOENT;
 167         }
 168
 169         if (test_and_clear_bit(b, lut->lut_reply_bitmap[chunk]) == 0) {
 170                 CERROR("%s: slot %d already clear in bitmap\n",
 171                        tgt_name(lut), idx);
 172                 return -EALREADY;
 173         }
 174
 175         return 0;
 176 }
 177
 178
 179 /* Read header of reply_data file of target @tgt into structure @lrh */
 180 static int tgt_reply_header_read(const struct lu_env *env,
 181                                  struct lu_target *tgt,
 182                                  struct lsd_reply_header *lrh)
 183 {
 184         int                      rc;
 185         struct lsd_reply_header  buf;
 186         struct tgt_thread_info  *tti = tgt_th_info(env);
 187
 188         tti->tti_off = 0;
 189         tti->tti_buf.lb_buf = &buf;
 190         tti->tti_buf.lb_len = sizeof(buf);
 191
 192         rc = dt_record_read(env, tgt->lut_reply_data, &tti->tti_buf,
 193                             &tti->tti_off);
 194         if (rc != 0)
 195                 return rc;
 196
 197         lrh->lrh_magic = le32_to_cpu(buf.lrh_magic);
 198         lrh->lrh_header_size = le32_to_cpu(buf.lrh_header_size);
 199         lrh->lrh_reply_size = le32_to_cpu(buf.lrh_reply_size);
 200
 201         CDEBUG(D_HA, "%s: read %s header. magic=0x%08x "
 202                "header_size=%d reply_size=%d\n",
 203                 tgt->lut_obd->obd_name, REPLY_DATA,
 204                 lrh->lrh_magic, lrh->lrh_header_size, lrh->lrh_reply_size);
 205
 206         return 0;
 207 }
 208
 209 /* Write header into replay_data file of target @tgt from structure @lrh */
 210 static int tgt_reply_header_write(const struct lu_env *env,
 211                                   struct lu_target *tgt,
 212                                   struct lsd_reply_header *lrh)
 213 {
 214         int                      rc;
 215         struct lsd_reply_header  buf;
 216         struct tgt_thread_info  *tti = tgt_th_info(env);
 217         struct thandle          *th;
 218         struct dt_object        *dto;
 219
 220         CDEBUG(D_HA, "%s: write %s header. magic=0x%08x "
 221                "header_size=%d reply_size=%d\n",
 222                 tgt->lut_obd->obd_name, REPLY_DATA,
 223                 lrh->lrh_magic, lrh->lrh_header_size, lrh->lrh_reply_size);
 224
 225         if (tgt->lut_bottom->dd_rdonly)
 226                 RETURN(0);
 227
 228         buf.lrh_magic = cpu_to_le32(lrh->lrh_magic);
 229         buf.lrh_header_size = cpu_to_le32(lrh->lrh_header_size);
 230         buf.lrh_reply_size = cpu_to_le32(lrh->lrh_reply_size);
 231
 232         th = dt_trans_create(env, tgt->lut_bottom);
 233         if (IS_ERR(th))
 234                 return PTR_ERR(th);
 235         th->th_sync = 1;
 236
 237         tti->tti_off = 0;
 238         tti->tti_buf.lb_buf = &buf;
 239         tti->tti_buf.lb_len = sizeof(buf);
 240
 241         rc = dt_declare_record_write(env, tgt->lut_reply_data,
 242                                      &tti->tti_buf, tti->tti_off, th);
 243         if (rc)
 244                 GOTO(out, rc);
 245
 246         rc = dt_trans_start(env, tgt->lut_bottom, th);
 247         if (rc)
 248                 GOTO(out, rc);
 249
 250         dto = dt_object_locate(tgt->lut_reply_data, th->th_dev);
 251         rc = dt_record_write(env, dto, &tti->tti_buf, &tti->tti_off, th);
 252 out:
 253         dt_trans_stop(env, tgt->lut_bottom, th);
 254         return rc;
 255 }
 256
 257 /* Write the reply data @lrd into reply_data file of target @tgt
 258  * at offset @off
 259  */
 260 static int tgt_reply_data_write(const struct lu_env *env, struct lu_target *tgt,
 261                                 struct lsd_reply_data *lrd, loff_t off,
 262                                 struct thandle *th)
 263 {
 264         struct tgt_thread_info  *tti = tgt_th_info(env);
 265         struct dt_object        *dto;
 266         struct lsd_reply_data   *buf = &tti->tti_lrd;
 267
 268         lrd->lrd_result = ptlrpc_status_hton(lrd->lrd_result);
 269
 270         buf->lrd_transno         = cpu_to_le64(lrd->lrd_transno);
 271         buf->lrd_xid             = cpu_to_le64(lrd->lrd_xid);
 272         buf->lrd_data            = cpu_to_le64(lrd->lrd_data);
 273         buf->lrd_result          = cpu_to_le32(lrd->lrd_result);
 274         buf->lrd_client_gen      = cpu_to_le32(lrd->lrd_client_gen);
 275
 276         lrd->lrd_result = ptlrpc_status_ntoh(lrd->lrd_result);
 277
 278         tti->tti_off = off;
 279         tti->tti_buf.lb_buf = buf;
 280         tti->tti_buf.lb_len = sizeof(*buf);
 281
 282         dto = dt_object_locate(tgt->lut_reply_data, th->th_dev);
 283         return dt_record_write(env, dto, &tti->tti_buf, &tti->tti_off, th);
 284 }
 285
 286 /* Read the reply data from reply_data file of target @tgt at offset @off
 287  * into structure @lrd
 288  */
 289 static int tgt_reply_data_read(const struct lu_env *env, struct lu_target *tgt,
 290                                struct lsd_reply_data *lrd, loff_t off)
 291 {
 292         int                      rc;
 293         struct tgt_thread_info  *tti = tgt_th_info(env);
 294         struct lsd_reply_data   *buf = &tti->tti_lrd;
 295
 296         tti->tti_off = off;
 297         tti->tti_buf.lb_buf = buf;
 298         tti->tti_buf.lb_len = sizeof(*buf);
 299
 300         rc = dt_record_read(env, tgt->lut_reply_data, &tti->tti_buf,
 301                             &tti->tti_off);
 302         if (rc != 0)
 303                 return rc;
 304
 305         lrd->lrd_transno         = le64_to_cpu(buf->lrd_transno);
 306         lrd->lrd_xid             = le64_to_cpu(buf->lrd_xid);
 307         lrd->lrd_data            = le64_to_cpu(buf->lrd_data);
 308         lrd->lrd_result          = le32_to_cpu(buf->lrd_result);
 309         lrd->lrd_client_gen      = le32_to_cpu(buf->lrd_client_gen);
 310         lrd->lrd_batch_idx       = le32_to_cpu(buf->lrd_batch_idx);
 311         return 0;
 312 }
 313
 314
 315 /* Free the in-memory reply data structure @trd and release
 316  * the corresponding slot in the reply_data file of target @lut
 317  * Called with ted_lcd_lock held
 318  */
 319 static void tgt_free_reply_data(struct lu_target *lut,
 320                                 struct tg_export_data *ted,
 321                                 struct tg_reply_data *trd)
 322 {
 323         CDEBUG(D_TRACE, "%s: free reply data %p: xid %llu, transno %llu, "
 324                "client gen %u, slot idx %d\n",
 325                lut == NULL ? "" : tgt_name(lut), trd, trd->trd_reply.lrd_xid,
 326                trd->trd_reply.lrd_transno, trd->trd_reply.lrd_client_gen,
 327                trd->trd_index);
 328
 329         LASSERT(mutex_is_locked(&ted->ted_lcd_lock));
 330
 331         list_del(&trd->trd_list);
 332         ted->ted_reply_cnt--;
 333         if (lut != NULL && trd->trd_index != TRD_INDEX_MEMORY)
 334                 tgt_clear_reply_slot(lut, trd->trd_index);
 335         OBD_FREE_PTR(trd);
 336 }
 337
 338 /* Release the reply data @trd from target @lut
 339  * The reply data with the highest transno for this export
 340  * is retained to ensure correctness of target recovery
 341  * Called with ted_lcd_lock held
 342  */
 343 static void tgt_release_reply_data(struct lu_target *lut,
 344                                    struct tg_export_data *ted,
 345                                    struct tg_reply_data *trd)
 346 {
 347         CDEBUG(D_TRACE, "%s: release reply data %p: xid %llu, transno %llu, "
 348                "client gen %u, slot idx %d\n",
 349                lut == NULL ? "" : tgt_name(lut), trd, trd->trd_reply.lrd_xid,
 350                trd->trd_reply.lrd_transno, trd->trd_reply.lrd_client_gen,
 351                trd->trd_index);
 352
 353         LASSERT(mutex_is_locked(&ted->ted_lcd_lock));
 354
 355         /* Do not free the reply data corresponding to the
 356          * highest transno of this export.
 357          * This ensures on-disk reply data is kept and
 358          * last committed transno can be restored from disk in case
 359          * of target recovery
 360          */
 361         if (trd->trd_reply.lrd_transno == ted->ted_lcd->lcd_last_transno) {
 362                 /* free previous retained reply */
 363                 if (ted->ted_reply_last != NULL)
 364                         tgt_free_reply_data(lut, ted, ted->ted_reply_last);
 365                 /* retain the reply */
 366                 list_del_init(&trd->trd_list);
 367                 ted->ted_reply_last = trd;
 368         } else {
 369                 tgt_free_reply_data(lut, ted, trd);
 370         }
 371 }
 372
 373 static inline struct lu_buf *tti_buf_lsd(struct tgt_thread_info *tti)
 374 {
 375         tti->tti_buf.lb_buf = &tti->tti_lsd;
 376         tti->tti_buf.lb_len = sizeof(tti->tti_lsd);
 377         return &tti->tti_buf;
 378 }
 379
 380 static inline struct lu_buf *tti_buf_lcd(struct tgt_thread_info *tti)
 381 {
 382         tti->tti_buf.lb_buf = &tti->tti_lcd;
 383         tti->tti_buf.lb_len = sizeof(tti->tti_lcd);
 384         return &tti->tti_buf;
 385 }
 386
 387 static inline bool tgt_is_multimodrpcs_record(struct lu_target *tgt,
 388                                               struct lsd_client_data *lcd)
 389 {
 390         return tgt->lut_lsd.lsd_feature_incompat & OBD_INCOMPAT_MULTI_RPCS &&
 391                 lcd->lcd_generation != 0;
 392 }
 393
 394 /**
 395  * Allocate in-memory data for client slot related to export.
 396  */
 397 int tgt_client_alloc(struct obd_export *exp)
 398 {
 399         ENTRY;
 400         LASSERT(exp != exp->exp_obd->obd_self_export);
 401
 402         spin_lock_init(&exp->exp_target_data.ted_nodemap_lock);
 403         INIT_LIST_HEAD(&exp->exp_target_data.ted_nodemap_member);
 404         spin_lock_init(&exp->exp_target_data.ted_fmd_lock);
 405         INIT_LIST_HEAD(&exp->exp_target_data.ted_fmd_list);
 406
 407         OBD_ALLOC_PTR(exp->exp_target_data.ted_lcd);
 408         if (exp->exp_target_data.ted_lcd == NULL)
 409                 RETURN(-ENOMEM);
 410         /* Mark that slot is not yet valid, 0 doesn't work here */
 411         exp->exp_target_data.ted_lr_idx = -1;
 412         INIT_LIST_HEAD(&exp->exp_target_data.ted_reply_list);
 413         mutex_init(&exp->exp_target_data.ted_lcd_lock);
 414         RETURN(0);
 415 }
 416 EXPORT_SYMBOL(tgt_client_alloc);
 417
 418 /**
 419  * Free in-memory data for client slot related to export.
 420  */
 421 void tgt_client_free(struct obd_export *exp)
 422 {
 423         struct tg_export_data   *ted = &exp->exp_target_data;
 424         struct lu_target        *lut = class_exp2tgt(exp);
 425         struct tg_reply_data    *trd, *tmp;
 426
 427         LASSERT(exp != exp->exp_obd->obd_self_export);
 428
 429         tgt_fmd_cleanup(exp);
 430
 431         /* free reply data */
 432         mutex_lock(&ted->ted_lcd_lock);
 433         list_for_each_entry_safe(trd, tmp, &ted->ted_reply_list, trd_list) {
 434                 tgt_release_reply_data(lut, ted, trd);
 435         }
 436         if (ted->ted_reply_last != NULL) {
 437                 tgt_free_reply_data(lut, ted, ted->ted_reply_last);
 438                 ted->ted_reply_last = NULL;
 439         }
 440         mutex_unlock(&ted->ted_lcd_lock);
 441
 442         if (!hlist_unhashed(&exp->exp_gen_hash))
 443                 cfs_hash_del(exp->exp_obd->obd_gen_hash,
 444                              &ted->ted_lcd->lcd_generation,
 445                              &exp->exp_gen_hash);
 446
 447         OBD_FREE_PTR(ted->ted_lcd);
 448         ted->ted_lcd = NULL;
 449
 450         /* Target may have been freed (see LU-7430)
 451          * Slot may be not yet assigned */
 452         if (((struct obd_device_target *)(&exp->exp_obd->u))->obt_magic !=
 453             OBT_MAGIC ||
 454             ted->ted_lr_idx < 0)
 455                 return;
 456
 457         /* Clear bit when lcd is freed */
 458         LASSERT(lut && lut->lut_client_bitmap);
 459         if (!test_and_clear_bit(ted->ted_lr_idx, lut->lut_client_bitmap)) {
 460                 CERROR("%s: client %u bit already clear in bitmap\n",
 461                        exp->exp_obd->obd_name, ted->ted_lr_idx);
 462                 LBUG();
 463         }
 464 }
 465 EXPORT_SYMBOL(tgt_client_free);
 466
 467 static inline void tgt_check_lcd(const char *obd_name, int index,
 468                                  struct lsd_client_data *lcd)
 469 {
 470         size_t uuid_size = sizeof(lcd->lcd_uuid);
 471
 472         if (strnlen((char*)lcd->lcd_uuid, uuid_size) == uuid_size) {
 473                 lcd->lcd_uuid[uuid_size - 1] = '\0';
 474
 475                 LCONSOLE_ERROR("the client UUID (%s) on %s for exports stored in last_rcvd(index = %d) is bad!\n",
 476                                lcd->lcd_uuid, obd_name, index);
 477         }
 478 }
 479
 480 static int tgt_client_data_read(const struct lu_env *env, struct lu_target *tgt,
 481                                 struct lsd_client_data *lcd,
 482                                 loff_t *off, int index)
 483 {
 484         struct tgt_thread_info  *tti = tgt_th_info(env);
 485         int                      rc;
 486
 487         tti_buf_lcd(tti);
 488         rc = dt_record_read(env, tgt->lut_last_rcvd, &tti->tti_buf, off);
 489         if (rc == 0) {
 490                 tgt_check_lcd(tgt->lut_obd->obd_name, index, &tti->tti_lcd);
 491                 lcd_le_to_cpu(&tti->tti_lcd, lcd);
 492                 lcd->lcd_last_result = ptlrpc_status_ntoh(lcd->lcd_last_result);
 493                 lcd->lcd_last_close_result =
 494                         ptlrpc_status_ntoh(lcd->lcd_last_close_result);
 495         }
 496
 497         CDEBUG(D_INFO, "%s: read lcd @%lld uuid = %s, last_transno = %llu"
 498                ", last_xid = %llu, last_result = %u, last_data = %u, "
 499                "last_close_transno = %llu, last_close_xid = %llu, "
 500                "last_close_result = %u, rc = %d\n", tgt->lut_obd->obd_name,
 501                *off, lcd->lcd_uuid, lcd->lcd_last_transno, lcd->lcd_last_xid,
 502                lcd->lcd_last_result, lcd->lcd_last_data,
 503                lcd->lcd_last_close_transno, lcd->lcd_last_close_xid,
 504                lcd->lcd_last_close_result, rc);
 505         return rc;
 506 }
 507
 508 static int tgt_client_data_write(const struct lu_env *env,
 509                                  struct lu_target *tgt,
 510                                  struct lsd_client_data *lcd,
 511                                  loff_t *off, struct thandle *th)
 512 {
 513         struct tgt_thread_info *tti = tgt_th_info(env);
 514         struct dt_object        *dto;
 515
 516         lcd->lcd_last_result = ptlrpc_status_hton(lcd->lcd_last_result);
 517         lcd->lcd_last_close_result =
 518                 ptlrpc_status_hton(lcd->lcd_last_close_result);
 519         lcd_cpu_to_le(lcd, &tti->tti_lcd);
 520         tti_buf_lcd(tti);
 521
 522         dto = dt_object_locate(tgt->lut_last_rcvd, th->th_dev);
 523         return dt_record_write(env, dto, &tti->tti_buf, off, th);
 524 }
 525
 526 struct tgt_new_client_callback {
 527         struct dt_txn_commit_cb  lncc_cb;
 528         struct obd_export       *lncc_exp;
 529 };
 530
 531 static void tgt_cb_new_client(struct lu_env *env, struct thandle *th,
 532                               struct dt_txn_commit_cb *cb, int err)
 533 {
 534         struct tgt_new_client_callback *ccb;
 535
 536         ccb = container_of(cb, struct tgt_new_client_callback, lncc_cb);
 537
 538         LASSERT(ccb->lncc_exp->exp_obd);
 539
 540         CDEBUG(D_RPCTRACE, "%s: committing for initial connect of %s\n",
 541                ccb->lncc_exp->exp_obd->obd_name,
 542                ccb->lncc_exp->exp_client_uuid.uuid);
 543
 544         spin_lock(&ccb->lncc_exp->exp_lock);
 545
 546         ccb->lncc_exp->exp_need_sync = 0;
 547
 548         spin_unlock(&ccb->lncc_exp->exp_lock);
 549         class_export_cb_put(ccb->lncc_exp);
 550
 551         OBD_FREE_PTR(ccb);
 552 }
 553
 554 int tgt_new_client_cb_add(struct thandle *th, struct obd_export *exp)
 555 {
 556         struct tgt_new_client_callback  *ccb;
 557         struct dt_txn_commit_cb         *dcb;
 558         int                              rc;
 559
 560         OBD_ALLOC_PTR(ccb);
 561         if (ccb == NULL)
 562                 return -ENOMEM;
 563
 564         ccb->lncc_exp = class_export_cb_get(exp);
 565
 566         dcb = &ccb->lncc_cb;
 567         dcb->dcb_func = tgt_cb_new_client;
 568         INIT_LIST_HEAD(&dcb->dcb_linkage);
 569         strlcpy(dcb->dcb_name, "tgt_cb_new_client", sizeof(dcb->dcb_name));
 570
 571         rc = dt_trans_cb_add(th, dcb);
 572         if (rc) {
 573                 class_export_cb_put(exp);
 574                 OBD_FREE_PTR(ccb);
 575         }
 576         return rc;
 577 }
 578
 579 /**
 580  * Update client data in last_rcvd
 581  */
 582 static int tgt_client_data_update(const struct lu_env *env,
 583                                   struct obd_export *exp)
 584 {
 585         struct tg_export_data   *ted = &exp->exp_target_data;
 586         struct lu_target        *tgt = class_exp2tgt(exp);
 587         struct tgt_thread_info  *tti = tgt_th_info(env);
 588         struct thandle          *th;
 589         int                      rc = 0;
 590
 591         ENTRY;
 592
 593         if (unlikely(tgt == NULL)) {
 594                 CDEBUG(D_ERROR, "%s: No target for connected export\n",
 595                           class_exp2obd(exp)->obd_name);
 596                 RETURN(-EINVAL);
 597         }
 598
 599         if (tgt->lut_bottom->dd_rdonly)
 600                 RETURN(0);
 601
 602         th = dt_trans_create(env, tgt->lut_bottom);
 603         if (IS_ERR(th))
 604                 RETURN(PTR_ERR(th));
 605
 606         tti_buf_lcd(tti);
 607         rc = dt_declare_record_write(env, tgt->lut_last_rcvd,
 608                                      &tti->tti_buf,
 609                                      ted->ted_lr_off, th);
 610         if (rc)
 611                 GOTO(out, rc);
 612
 613         rc = dt_trans_start_local(env, tgt->lut_bottom, th);
 614         if (rc)
 615                 GOTO(out, rc);
 616
 617         mutex_lock(&ted->ted_lcd_lock);
 618
 619         /*
 620          * Until this operations will be committed the sync is needed
 621          * for this export. This should be done _after_ starting the
 622          * transaction so that many connecting clients will not bring
 623          * server down with lots of sync writes.
 624          */
 625         rc = tgt_new_client_cb_add(th, exp);
 626         if (rc) {
 627                 /* can't add callback, do sync now */
 628                 th->th_sync = 1;
 629         } else {
 630                 spin_lock(&exp->exp_lock);
 631                 exp->exp_need_sync = 1;
 632                 spin_unlock(&exp->exp_lock);
 633         }
 634
 635         tti->tti_off = ted->ted_lr_off;
 636         rc = tgt_client_data_write(env, tgt, ted->ted_lcd, &tti->tti_off, th);
 637
 638         mutex_unlock(&ted->ted_lcd_lock);
 639
 640         EXIT;
 641 out:
 642         dt_trans_stop(env, tgt->lut_bottom, th);
 643         CDEBUG(D_INFO, "%s: update last_rcvd client data for UUID = %s, "
 644                "last_transno = %llu: rc = %d\n", tgt->lut_obd->obd_name,
 645                tgt->lut_lsd.lsd_uuid, tgt->lut_lsd.lsd_last_transno, rc);
 646
 647         return rc;
 648 }
 649
 650 static int tgt_server_data_read(const struct lu_env *env, struct lu_target *tgt)
 651 {
 652         struct tgt_thread_info  *tti = tgt_th_info(env);
 653         int                      rc;
 654
 655         tti->tti_off = 0;
 656         tti_buf_lsd(tti);
 657         rc = dt_record_read(env, tgt->lut_last_rcvd, &tti->tti_buf,
 658                             &tti->tti_off);
 659         if (rc == 0)
 660                 lsd_le_to_cpu(&tti->tti_lsd, &tgt->lut_lsd);
 661
 662         CDEBUG(D_INFO, "%s: read last_rcvd server data for UUID = %s, "
 663                "last_transno = %llu: rc = %d\n", tgt->lut_obd->obd_name,
 664                tgt->lut_lsd.lsd_uuid, tgt->lut_lsd.lsd_last_transno, rc);
 665         return rc;
 666 }
 667
 668 static int tgt_server_data_write(const struct lu_env *env,
 669                                  struct lu_target *tgt, struct thandle *th)
 670 {
 671         struct tgt_thread_info  *tti = tgt_th_info(env);
 672         struct dt_object        *dto;
 673         int                      rc;
 674
 675         ENTRY;
 676
 677         tti->tti_off = 0;
 678         tti_buf_lsd(tti);
 679         lsd_cpu_to_le(&tgt->lut_lsd, &tti->tti_lsd);
 680
 681         dto = dt_object_locate(tgt->lut_last_rcvd, th->th_dev);
 682         rc = dt_record_write(env, dto, &tti->tti_buf, &tti->tti_off, th);
 683
 684         CDEBUG(D_INFO, "%s: write last_rcvd server data for UUID = %s, "
 685                "last_transno = %llu: rc = %d\n", tgt->lut_obd->obd_name,
 686                tgt->lut_lsd.lsd_uuid, tgt->lut_lsd.lsd_last_transno, rc);
 687
 688         RETURN(rc);
 689 }
 690
 691 /**
 692  * Update server data in last_rcvd
 693  */
 694 int tgt_server_data_update(const struct lu_env *env, struct lu_target *tgt,
 695                            int sync)
 696 {
 697         struct tgt_thread_info  *tti = tgt_th_info(env);
 698         struct thandle          *th;
 699         int                      rc = 0;
 700
 701         ENTRY;
 702
 703         CDEBUG(D_SUPER,
 704                "%s: mount_count is %llu, last_transno is %llu\n",
 705                tgt->lut_lsd.lsd_uuid, obd2obt(tgt->lut_obd)->obt_mount_count,
 706                tgt->lut_last_transno);
 707
 708         /* Always save latest transno to keep it fresh */
 709         spin_lock(&tgt->lut_translock);
 710         tgt->lut_lsd.lsd_last_transno = tgt->lut_last_transno;
 711         spin_unlock(&tgt->lut_translock);
 712
 713         if (tgt->lut_bottom->dd_rdonly)
 714                 RETURN(0);
 715
 716         th = dt_trans_create(env, tgt->lut_bottom);
 717         if (IS_ERR(th))
 718                 RETURN(PTR_ERR(th));
 719
 720         th->th_sync = sync;
 721
 722         tti_buf_lsd(tti);
 723         rc = dt_declare_record_write(env, tgt->lut_last_rcvd,
 724                                      &tti->tti_buf, tti->tti_off, th);
 725         if (rc)
 726                 GOTO(out, rc);
 727
 728         rc = dt_trans_start(env, tgt->lut_bottom, th);
 729         if (rc)
 730                 GOTO(out, rc);
 731
 732         rc = tgt_server_data_write(env, tgt, th);
 733 out:
 734         dt_trans_stop(env, tgt->lut_bottom, th);
 735
 736         CDEBUG(D_INFO, "%s: update last_rcvd server data for UUID = %s, "
 737                "last_transno = %llu: rc = %d\n", tgt->lut_obd->obd_name,
 738                tgt->lut_lsd.lsd_uuid, tgt->lut_lsd.lsd_last_transno, rc);
 739         RETURN(rc);
 740 }
 741 EXPORT_SYMBOL(tgt_server_data_update);
 742
 743 static int tgt_truncate_last_rcvd(const struct lu_env *env,
 744                                   struct lu_target *tgt, loff_t size)
 745 {
 746         struct dt_object *dt = tgt->lut_last_rcvd;
 747         struct thandle   *th;
 748         struct lu_attr    attr;
 749         int               rc;
 750
 751         ENTRY;
 752
 753         if (tgt->lut_bottom->dd_rdonly)
 754                 RETURN(0);
 755
 756         attr.la_size = size;
 757         attr.la_valid = LA_SIZE;
 758
 759         th = dt_trans_create(env, tgt->lut_bottom);
 760         if (IS_ERR(th))
 761                 RETURN(PTR_ERR(th));
 762         rc = dt_declare_punch(env, dt, size, OBD_OBJECT_EOF, th);
 763         if (rc)
 764                 GOTO(cleanup, rc);
 765         rc = dt_declare_attr_set(env, dt, &attr, th);
 766         if (rc)
 767                 GOTO(cleanup, rc);
 768         rc = dt_trans_start_local(env, tgt->lut_bottom, th);
 769         if (rc)
 770                 GOTO(cleanup, rc);
 771
 772         rc = dt_punch(env, dt, size, OBD_OBJECT_EOF, th);
 773         if (rc == 0)
 774                 rc = dt_attr_set(env, dt, &attr, th);
 775
 776 cleanup:
 777         dt_trans_stop(env, tgt->lut_bottom, th);
 778
 779         RETURN(rc);
 780 }
 781
 782 static void tgt_client_epoch_update(const struct lu_env *env,
 783                                     struct obd_export *exp)
 784 {
 785         struct lsd_client_data  *lcd = exp->exp_target_data.ted_lcd;
 786         struct lu_target        *tgt = class_exp2tgt(exp);
 787
 788         LASSERT(tgt && tgt->lut_bottom);
 789         /** VBR: set client last_epoch to current epoch */
 790         if (lcd->lcd_last_epoch >= tgt->lut_lsd.lsd_start_epoch)
 791                 return;
 792         lcd->lcd_last_epoch = tgt->lut_lsd.lsd_start_epoch;
 793         tgt_client_data_update(env, exp);
 794 }
 795
 796 /**
 797  * Update boot epoch when recovery ends
 798  */
 799 void tgt_boot_epoch_update(struct lu_target *tgt)
 800 {
 801         struct lu_env            env;
 802         struct ptlrpc_request   *req;
 803         __u32                    start_epoch;
 804         LIST_HEAD(client_list);
 805         int                      rc;
 806
 807         if (tgt->lut_obd->obd_stopping)
 808                 return;
 809
 810         rc = lu_env_init(&env, LCT_DT_THREAD);
 811         if (rc) {
 812                 CERROR("%s: can't initialize environment: rc = %d\n",
 813                         tgt->lut_obd->obd_name, rc);
 814                 return;
 815         }
 816
 817         spin_lock(&tgt->lut_translock);
 818         start_epoch = (tgt->lut_last_transno >> LR_EPOCH_BITS) + 1;
 819         tgt->lut_last_transno = (__u64)start_epoch << LR_EPOCH_BITS;
 820         tgt->lut_lsd.lsd_start_epoch = start_epoch;
 821         spin_unlock(&tgt->lut_translock);
 822
 823         /**
 824          * The recovery is not yet finished and final queue can still be updated
 825          * with resend requests. Move final list to separate one for processing
 826          */
 827         spin_lock(&tgt->lut_obd->obd_recovery_task_lock);
 828         list_splice_init(&tgt->lut_obd->obd_final_req_queue, &client_list);
 829         spin_unlock(&tgt->lut_obd->obd_recovery_task_lock);
 830
 831         /**
 832          * go through list of exports participated in recovery and
 833          * set new epoch for them
 834          */
 835         list_for_each_entry(req, &client_list, rq_list) {
 836                 LASSERT(!req->rq_export->exp_delayed);
 837                 if (!req->rq_export->exp_vbr_failed)
 838                         tgt_client_epoch_update(&env, req->rq_export);
 839         }
 840         /** return list back at once */
 841         spin_lock(&tgt->lut_obd->obd_recovery_task_lock);
 842         list_splice_init(&client_list, &tgt->lut_obd->obd_final_req_queue);
 843         spin_unlock(&tgt->lut_obd->obd_recovery_task_lock);
 844
 845         /**
 846          * Clear MULTI RPCS incompatibility flag if there is no multi-rpcs
 847          * client in last_rcvd file
 848          */
 849         if (atomic_read(&tgt->lut_num_clients) == 0)
 850                 tgt->lut_lsd.lsd_feature_incompat &= ~OBD_INCOMPAT_MULTI_RPCS;
 851
 852         /** update server epoch */
 853         tgt_server_data_update(&env, tgt, 1);
 854         lu_env_fini(&env);
 855 }
 856
 857 /**
 858  * commit callback, need to update last_committed value
 859  */
 860 struct tgt_last_committed_callback {
 861         struct dt_txn_commit_cb  llcc_cb;
 862         struct lu_target        *llcc_tgt;
 863         struct obd_export       *llcc_exp;
 864         __u64                    llcc_transno;
 865 };
 866
 867 static void tgt_cb_last_committed(struct lu_env *env, struct thandle *th,
 868                                   struct dt_txn_commit_cb *cb, int err)
 869 {
 870         struct tgt_last_committed_callback *ccb;
 871
 872         ccb = container_of(cb, struct tgt_last_committed_callback, llcc_cb);
 873
 874         LASSERT(ccb->llcc_exp);
 875         LASSERT(ccb->llcc_tgt != NULL);
 876         LASSERT(ccb->llcc_exp->exp_obd == ccb->llcc_tgt->lut_obd);
 877
 878         if (th->th_reserved_quota.lqi_space > 0) {
 879                 CDEBUG(D_QUOTA, "free quota %llu %llu\n",
 880                        th->th_reserved_quota.lqi_id.qid_gid,
 881                        th->th_reserved_quota.lqi_space);
 882
 883                 /* env can be NULL for freeing reserved quota */
 884                 th->th_reserved_quota.lqi_space *= -1;
 885                 dt_reserve_or_free_quota(NULL, th->th_dev,
 886                                          &th->th_reserved_quota);
 887         }
 888
 889         /* error hit, don't update last committed to provide chance to
 890          * replay data after fail */
 891         if (err != 0)
 892                 goto out;
 893
 894         /* Fast path w/o spinlock, if exp_last_committed was updated
 895          * with higher transno, no need to take spinlock and check,
 896          * also no need to update obd_last_committed. */
 897         if (ccb->llcc_transno <= ccb->llcc_exp->exp_last_committed)
 898                 goto out;
 899         spin_lock(&ccb->llcc_tgt->lut_translock);
 900         if (ccb->llcc_transno > ccb->llcc_tgt->lut_obd->obd_last_committed)
 901                 ccb->llcc_tgt->lut_obd->obd_last_committed = ccb->llcc_transno;
 902
 903         if (ccb->llcc_transno > ccb->llcc_exp->exp_last_committed) {
 904                 ccb->llcc_exp->exp_last_committed = ccb->llcc_transno;
 905                 spin_unlock(&ccb->llcc_tgt->lut_translock);
 906
 907                 ptlrpc_commit_replies(ccb->llcc_exp);
 908                 tgt_cancel_slc_locks(ccb->llcc_tgt, ccb->llcc_transno);
 909         } else {
 910                 spin_unlock(&ccb->llcc_tgt->lut_translock);
 911         }
 912
 913         CDEBUG(D_HA, "%s: transno %lld is committed\n",
 914                ccb->llcc_tgt->lut_obd->obd_name, ccb->llcc_transno);
 915
 916 out:
 917         class_export_cb_put(ccb->llcc_exp);
 918         OBD_FREE_PTR(ccb);
 919 }
 920
 921 /**
 922  * Add commit callback function, it returns a non-zero value to inform
 923  * caller to use sync transaction if necessary.
 924  */
 925 static int tgt_last_commit_cb_add(struct thandle *th, struct lu_target *tgt,
 926                                   struct obd_export *exp, __u64 transno)
 927 {
 928         struct tgt_last_committed_callback      *ccb;
 929         struct dt_txn_commit_cb                 *dcb;
 930         int                                      rc;
 931
 932         OBD_ALLOC_PTR(ccb);
 933         if (ccb == NULL)
 934                 return -ENOMEM;
 935
 936         ccb->llcc_tgt = tgt;
 937         ccb->llcc_exp = class_export_cb_get(exp);
 938         ccb->llcc_transno = transno;
 939
 940         dcb = &ccb->llcc_cb;
 941         dcb->dcb_func = tgt_cb_last_committed;
 942         INIT_LIST_HEAD(&dcb->dcb_linkage);
 943         strlcpy(dcb->dcb_name, "tgt_cb_last_committed", sizeof(dcb->dcb_name));
 944
 945         rc = dt_trans_cb_add(th, dcb);
 946         if (rc) {
 947                 class_export_cb_put(exp);
 948                 OBD_FREE_PTR(ccb);
 949         }
 950
 951         if (exp_connect_flags(exp) & OBD_CONNECT_LIGHTWEIGHT)
 952                 /* report failure to force synchronous operation */
 953                 return -EPERM;
 954
 955         /* if exp_need_sync is set, return non-zero value to force
 956          * a sync transaction. */
 957         return rc ? rc : exp->exp_need_sync;
 958 }
 959
 960 static int tgt_is_local_client(const struct lu_env *env,
 961                                       struct obd_export *exp)
 962 {
 963         struct lu_target        *tgt = class_exp2tgt(exp);
 964         struct tgt_session_info *tsi = tgt_ses_info(env);
 965         struct ptlrpc_request   *req = tgt_ses_req(tsi);
 966
 967         if (exp_connect_flags(exp) & OBD_CONNECT_MDS ||
 968             exp_connect_flags(exp) & OBD_CONNECT_MDS_MDS)
 969                 return 0;
 970         if (tgt->lut_local_recovery)
 971                 return 0;
 972         if (!req)
 973                 return 0;
 974         if (!LNetIsPeerLocal(&req->rq_peer.nid))
 975                 return 0;
 976
 977         return 1;
 978 }
 979
 980 /**
 981  * Add new client to the last_rcvd upon new connection.
 982  *
 983  * We use a bitmap to locate a free space in the last_rcvd file and initialize
 984  * tg_export_data.
 985  */
 986 int tgt_client_new(const struct lu_env *env, struct obd_export *exp)
 987 {
 988         struct tg_export_data   *ted = &exp->exp_target_data;
 989         struct lu_target        *tgt = class_exp2tgt(exp);
 990         int                      rc = 0, idx;
 991
 992         ENTRY;
 993
 994         LASSERT(tgt && tgt->lut_client_bitmap != NULL);
 995         if (!strcmp(ted->ted_lcd->lcd_uuid, tgt->lut_obd->obd_uuid.uuid))
 996                 RETURN(0);
 997
 998         if (exp_connect_flags(exp) & OBD_CONNECT_LIGHTWEIGHT)
 999                 RETURN(0);
1000
1001         if (tgt_is_local_client(env, exp)) {
1002                 LCONSOLE_WARN("%s: local client %s w/o recovery\n",
1003                               exp->exp_obd->obd_name, ted->ted_lcd->lcd_uuid);
1004                 exp->exp_no_recovery = 1;
1005                 RETURN(0);
1006         }
1007
1008         /* the bitmap operations can handle cl_idx > sizeof(long) * 8, so
1009          * there's no need for extra complication here
1010          */
1011         idx = find_first_zero_bit(tgt->lut_client_bitmap, LR_MAX_CLIENTS);
1012 repeat:
1013         if (idx >= LR_MAX_CLIENTS ||
1014             OBD_FAIL_CHECK(OBD_FAIL_MDS_CLIENT_ADD)) {
1015                 CERROR("%s: no room for %u clients - fix LR_MAX_CLIENTS\n",
1016                        tgt->lut_obd->obd_name,  idx);
1017                 RETURN(-EOVERFLOW);
1018         }
1019         if (test_and_set_bit(idx, tgt->lut_client_bitmap)) {
1020                 idx = find_next_zero_bit(tgt->lut_client_bitmap,
1021                                              LR_MAX_CLIENTS, idx);
1022                 goto repeat;
1023         }
1024
1025         ted->ted_lr_idx = idx;
1026         ted->ted_lr_off = tgt->lut_lsd.lsd_client_start +
1027                           idx * tgt->lut_lsd.lsd_client_size;
1028
1029         LASSERTF(ted->ted_lr_off > 0, "ted_lr_off = %llu\n", ted->ted_lr_off);
1030
1031         if (tgt_is_multimodrpcs_client(exp)) {
1032                 /* Set MULTI RPCS incompatibility flag to prevent previous
1033                  * Lustre versions to mount a target with reply_data file */
1034                 if (!(tgt->lut_lsd.lsd_feature_incompat &
1035                       OBD_INCOMPAT_MULTI_RPCS)) {
1036                         tgt->lut_lsd.lsd_feature_incompat |=
1037                                                         OBD_INCOMPAT_MULTI_RPCS;
1038                         rc = tgt_server_data_update(env, tgt, 1);
1039                         if (rc < 0) {
1040                                 CERROR("%s: unable to set MULTI RPCS "
1041                                        "incompatibility flag\n",
1042                                        exp->exp_obd->obd_name);
1043                                 RETURN(rc);
1044                         }
1045                 }
1046
1047                 /* assign client slot generation */
1048                 ted->ted_lcd->lcd_generation =
1049                                 atomic_inc_return(&tgt->lut_client_generation);
1050         } else {
1051                 ted->ted_lcd->lcd_generation = 0;
1052         }
1053
1054         CDEBUG(D_INFO, "%s: new client at index %d (%llu) with UUID '%s' "
1055                "generation %d\n",
1056                tgt->lut_obd->obd_name, ted->ted_lr_idx, ted->ted_lr_off,
1057                ted->ted_lcd->lcd_uuid, ted->ted_lcd->lcd_generation);
1058
1059         if (OBD_FAIL_CHECK(OBD_FAIL_TGT_CLIENT_ADD))
1060                 RETURN(-ENOSPC);
1061
1062         rc = tgt_client_data_update(env, exp);
1063         if (rc) {
1064                 CERROR("%s: Failed to write client lcd at idx %d, rc %d\n",
1065                        tgt->lut_obd->obd_name, idx, rc);
1066                 RETURN(rc);
1067         }
1068
1069         if (tgt_is_multimodrpcs_client(exp))
1070                 atomic_inc(&tgt->lut_num_clients);
1071
1072         RETURN(0);
1073 }
1074 EXPORT_SYMBOL(tgt_client_new);
1075
1076 /* Add an existing client to the MDS in-memory state based on
1077  * a client that was previously found in the last_rcvd file and
1078  * already has an assigned slot (idx >= 0).
1079  *
1080  * It should not be possible to fail adding an existing client - otherwise
1081  * mdt_init_server_data() callsite needs to be fixed.
1082  */
1083 int tgt_client_add(const struct lu_env *env,  struct obd_export *exp, int idx)
1084 {
1085         struct tg_export_data   *ted = &exp->exp_target_data;
1086         struct lu_target        *tgt = class_exp2tgt(exp);
1087
1088         ENTRY;
1089
1090         LASSERT(tgt && tgt->lut_client_bitmap != NULL);
1091         LASSERTF(idx >= 0, "%d\n", idx);
1092
1093         if (!strcmp(ted->ted_lcd->lcd_uuid, tgt->lut_obd->obd_uuid.uuid) ||
1094             exp_connect_flags(exp) & OBD_CONNECT_LIGHTWEIGHT)
1095                 RETURN(0);
1096
1097         if (test_and_set_bit(idx, tgt->lut_client_bitmap)) {
1098                 CERROR("%s: client %d: bit already set in bitmap!!\n",
1099                        tgt->lut_obd->obd_name,  idx);
1100                 LBUG();
1101         }
1102
1103         CDEBUG(D_INFO, "%s: client at idx %d with UUID '%s' added, "
1104                "generation %d\n",
1105                tgt->lut_obd->obd_name, idx, ted->ted_lcd->lcd_uuid,
1106                ted->ted_lcd->lcd_generation);
1107
1108         ted->ted_lr_idx = idx;
1109         ted->ted_lr_off = tgt->lut_lsd.lsd_client_start +
1110                           idx * tgt->lut_lsd.lsd_client_size;
1111
1112         mutex_init(&ted->ted_lcd_lock);
1113
1114         LASSERTF(ted->ted_lr_off > 0, "ted_lr_off = %llu\n", ted->ted_lr_off);
1115
1116         RETURN(0);
1117 }
1118
1119 int tgt_client_del(const struct lu_env *env, struct obd_export *exp)
1120 {
1121         struct tg_export_data   *ted = &exp->exp_target_data;
1122         struct lu_target        *tgt = class_exp2tgt(exp);
1123         int                      rc;
1124
1125         ENTRY;
1126
1127         LASSERT(ted->ted_lcd);
1128
1129         if (unlikely(tgt == NULL)) {
1130                 CDEBUG(D_ERROR, "%s: No target for connected export\n",
1131                        class_exp2obd(exp)->obd_name);
1132                 RETURN(-EINVAL);
1133         }
1134
1135         /* XXX if lcd_uuid were a real obd_uuid, I could use obd_uuid_equals */
1136         if (!strcmp((char *)ted->ted_lcd->lcd_uuid,
1137                     (char *)tgt->lut_obd->obd_uuid.uuid) ||
1138             exp_connect_flags(exp) & OBD_CONNECT_LIGHTWEIGHT ||
1139             exp->exp_no_recovery)
1140                 RETURN(0);
1141
1142         /* Slot may be not yet assigned, use case is race between Client
1143          * reconnect and forced eviction */
1144         if (ted->ted_lr_idx < 0) {
1145                 CWARN("%s: client with UUID '%s' not in bitmap\n",
1146                       tgt->lut_obd->obd_name, ted->ted_lcd->lcd_uuid);
1147                 RETURN(0);
1148         }
1149
1150         CDEBUG(D_INFO, "%s: del client at idx %u, off %lld, UUID '%s'\n",
1151                tgt->lut_obd->obd_name, ted->ted_lr_idx, ted->ted_lr_off,
1152                ted->ted_lcd->lcd_uuid);
1153
1154         /* Clear the bit _after_ zeroing out the client so we don't
1155            race with filter_client_add and zero out new clients.*/
1156         if (!test_bit(ted->ted_lr_idx, tgt->lut_client_bitmap)) {
1157                 CERROR("%s: client %u: bit already clear in bitmap!!\n",
1158                        tgt->lut_obd->obd_name, ted->ted_lr_idx);
1159                 LBUG();
1160         }
1161
1162         /* Do not erase record for recoverable client. */
1163         if (exp->exp_flags & OBD_OPT_FAILOVER)
1164                 RETURN(0);
1165
1166         if (OBD_FAIL_CHECK(OBD_FAIL_TGT_CLIENT_DEL))
1167                 RETURN(0);
1168
1169         /* Make sure the server's last_transno is up to date.
1170          * This should be done before zeroing client slot so last_transno will
1171          * be in server data or in client data in case of failure */
1172         rc = tgt_server_data_update(env, tgt, 0);
1173         if (rc != 0) {
1174                 CERROR("%s: failed to update server data, skip client %s "
1175                        "zeroing, rc %d\n", tgt->lut_obd->obd_name,
1176                        ted->ted_lcd->lcd_uuid, rc);
1177                 RETURN(rc);
1178         }
1179
1180         /* Race between an eviction and a disconnection ?*/
1181         mutex_lock(&ted->ted_lcd_lock);
1182         if (ted->ted_lcd->lcd_uuid[0] == '\0') {
1183                 mutex_unlock(&ted->ted_lcd_lock);
1184                 RETURN(rc);
1185         }
1186
1187         memset(ted->ted_lcd->lcd_uuid, 0, sizeof ted->ted_lcd->lcd_uuid);
1188         mutex_unlock(&ted->ted_lcd_lock);
1189
1190         rc = tgt_client_data_update(env, exp);
1191
1192         if (!rc && tgt_is_multimodrpcs_record(tgt, ted->ted_lcd))
1193                 atomic_dec(&tgt->lut_num_clients);
1194
1195         CDEBUG(rc == 0 ? D_INFO : D_ERROR,
1196                "%s: zeroing out client %s at idx %u (%llu), rc %d\n",
1197                tgt->lut_obd->obd_name, ted->ted_lcd->lcd_uuid,
1198                ted->ted_lr_idx, ted->ted_lr_off, rc);
1199         RETURN(rc);
1200 }
1201 EXPORT_SYMBOL(tgt_client_del);
1202
1203 static void tgt_clean_by_tag(struct obd_export *exp, __u64 xid, __u16 tag)
1204 {
1205         struct tg_export_data   *ted = &exp->exp_target_data;
1206         struct lu_target        *lut = class_exp2tgt(exp);
1207         struct tg_reply_data    *trd, *tmp;
1208
1209         if (tag == 0)
1210                 return;
1211
1212         list_for_each_entry_safe(trd, tmp, &ted->ted_reply_list, trd_list) {
1213                 if (trd->trd_tag != tag)
1214                         continue;
1215
1216                 LASSERT(ergo(tgt_is_increasing_xid_client(exp),
1217                              trd->trd_reply.lrd_xid <= xid));
1218
1219                 ted->ted_release_tag++;
1220                 tgt_release_reply_data(lut, ted, trd);
1221         }
1222 }
1223
1224 static int tgt_add_reply_data(const struct lu_env *env, struct lu_target *tgt,
1225                        struct tg_export_data *ted, struct tg_reply_data *trd,
1226                        struct ptlrpc_request *req,
1227                        struct thandle *th, bool update_lrd_file)
1228 {
1229         struct tgt_session_info *tsi = NULL;
1230         struct lsd_reply_data *lrd;
1231         int i = -1;
1232         int rc;
1233
1234         lrd = &trd->trd_reply;
1235         /* update export last transno */
1236         mutex_lock(&ted->ted_lcd_lock);
1237         if (lrd->lrd_transno > ted->ted_lcd->lcd_last_transno)
1238                 ted->ted_lcd->lcd_last_transno = lrd->lrd_transno;
1239         mutex_unlock(&ted->ted_lcd_lock);
1240
1241         if (!tgt) {
1242                 trd->trd_index = TRD_INDEX_MEMORY;
1243                 GOTO(add_reply_data, rc = 0);
1244         }
1245
1246         if (env) {
1247                 tsi = tgt_ses_info(env);
1248                 if (tsi->tsi_batch_trd) {
1249                         LASSERT(tsi->tsi_batch_env);
1250                         trd = tsi->tsi_batch_trd;
1251                         i = trd->trd_index;
1252                 }
1253         }
1254
1255         if (i == -1) {
1256                 /* find a empty slot */
1257                 i = tgt_find_free_reply_slot(tgt);
1258                 if (unlikely(i < 0)) {
1259                         CERROR("%s: couldn't find a slot for reply data: rc = %d\n",
1260                                tgt_name(tgt), i);
1261                         RETURN(i);
1262                 }
1263                 trd->trd_index = i;
1264         }
1265
1266         if (update_lrd_file) {
1267                 loff_t  off;
1268
1269                 /* write reply data to disk */
1270                 off = sizeof(struct lsd_reply_header) + sizeof(*lrd) * i;
1271                 rc = tgt_reply_data_write(env, tgt, lrd, off, th);
1272                 if (unlikely(rc != 0)) {
1273                         CERROR("%s: can't update %s file: rc = %d\n",
1274                                tgt_name(tgt), REPLY_DATA, rc);
1275                         GOTO(free_slot, rc);
1276                 }
1277         }
1278
1279 add_reply_data:
1280         /* add reply data to target export's reply list */
1281         mutex_lock(&ted->ted_lcd_lock);
1282         if (req != NULL) {
1283                 int exclude = tgt_is_increasing_xid_client(req->rq_export) ?
1284                               MSG_REPLAY : MSG_REPLAY|MSG_RESENT;
1285
1286                 if (req->rq_obsolete) {
1287                         CDEBUG(D_INFO,
1288                                "drop reply data update for obsolete req xid=%llu,"
1289                                "transno=%llu, tag=%hu\n", req->rq_xid,
1290                                lrd->lrd_transno, trd->trd_tag);
1291                         mutex_unlock(&ted->ted_lcd_lock);
1292                         GOTO(free_slot, rc = -EBADR);
1293                 }
1294
1295                 if (!(lustre_msg_get_flags(req->rq_reqmsg) & exclude) &&
1296                     !(tsi && tsi->tsi_batch_env &&
1297                       trd->trd_reply.lrd_batch_idx > 0))
1298                         tgt_clean_by_tag(req->rq_export, req->rq_xid,
1299                                          trd->trd_tag);
1300         }
1301
1302         /*
1303          * For the batched RPC, all sub requests use one common @trd for the
1304          * reply data.
1305          */
1306         if (list_empty(&trd->trd_list)) {
1307                 list_add(&trd->trd_list, &ted->ted_reply_list);
1308                 ted->ted_reply_cnt++;
1309                 if (ted->ted_reply_cnt > ted->ted_reply_max)
1310                         ted->ted_reply_max = ted->ted_reply_cnt;
1311         }
1312         mutex_unlock(&ted->ted_lcd_lock);
1313
1314         CDEBUG(D_TRACE, "add reply %p: xid %llu, transno %llu, "
1315                "tag %hu, client gen %u, slot idx %d\n",
1316                trd, lrd->lrd_xid, lrd->lrd_transno,
1317                trd->trd_tag, lrd->lrd_client_gen, trd->trd_index);
1318
1319         RETURN(0);
1320
1321 free_slot:
1322         if (tgt != NULL)
1323                 tgt_clear_reply_slot(tgt, trd->trd_index);
1324         return rc;
1325 }
1326
1327 int tgt_mk_reply_data(const struct lu_env *env,
1328                       struct lu_target *tgt,
1329                       struct tg_export_data *ted,
1330                       struct ptlrpc_request *req,
1331                       __u64 opdata,
1332                       struct thandle *th,
1333                       bool write_update,
1334                       __u64 transno)
1335 {
1336         struct tg_reply_data *trd = NULL;
1337         struct lsd_reply_data *lrd;
1338         __u64 *pre_versions = NULL;
1339         struct tgt_session_info *tsi = NULL;
1340         int rc;
1341
1342         if (env != NULL) {
1343                 tsi = tgt_ses_info(env);
1344                 if (tsi->tsi_batch_trd) {
1345                         LASSERT(tsi->tsi_batch_env);
1346                         trd = tsi->tsi_batch_trd;
1347                 }
1348         }
1349
1350         if (trd == NULL) {
1351                 OBD_ALLOC_PTR(trd);
1352                 if (unlikely(trd == NULL))
1353                         RETURN(-ENOMEM);
1354
1355                 INIT_LIST_HEAD(&trd->trd_list);
1356         }
1357
1358         /* fill reply data information */
1359         lrd = &trd->trd_reply;
1360         lrd->lrd_transno = transno;
1361         if (tsi && tsi->tsi_batch_env) {
1362                 if (tsi->tsi_batch_idx == 0) {
1363                         LASSERT(req != NULL);
1364                         tsi->tsi_batch_trd = trd;
1365                         trd->trd_index = -1;
1366                         lrd->lrd_xid = req->rq_xid;
1367                         trd->trd_tag = lustre_msg_get_tag(req->rq_reqmsg);
1368                         lrd->lrd_client_gen = ted->ted_lcd->lcd_generation;
1369                 }
1370                 lrd->lrd_batch_idx = tsi->tsi_batch_idx;
1371         } else if (req != NULL) {
1372                 lrd->lrd_xid = req->rq_xid;
1373                 trd->trd_tag = lustre_msg_get_tag(req->rq_reqmsg);
1374                 lrd->lrd_client_gen = ted->ted_lcd->lcd_generation;
1375                 if (write_update) {
1376                         pre_versions = lustre_msg_get_versions(req->rq_repmsg);
1377                         lrd->lrd_result = th->th_result;
1378                 }
1379         } else {
1380                 LASSERT(env != NULL);
1381                 LASSERT(tsi->tsi_xid != 0);
1382
1383                 lrd->lrd_xid = tsi->tsi_xid;
1384                 lrd->lrd_result = tsi->tsi_result;
1385                 lrd->lrd_client_gen = tsi->tsi_client_gen;
1386         }
1387
1388         lrd->lrd_data = opdata;
1389         if (pre_versions) {
1390                 trd->trd_pre_versions[0] = pre_versions[0];
1391                 trd->trd_pre_versions[1] = pre_versions[1];
1392                 trd->trd_pre_versions[2] = pre_versions[2];
1393                 trd->trd_pre_versions[3] = pre_versions[3];
1394         }
1395
1396         if (tsi && tsi->tsi_open_obj)
1397                 trd->trd_object = *lu_object_fid(&tsi->tsi_open_obj->do_lu);
1398
1399         rc = tgt_add_reply_data(env, tgt, ted, trd, req,
1400                                 th, write_update);
1401         if (rc < 0) {
1402                 OBD_FREE_PTR(trd);
1403                 if (rc == -EBADR)
1404                         rc = 0;
1405         }
1406         return rc;
1407
1408 }
1409 EXPORT_SYMBOL(tgt_mk_reply_data);
1410
1411 /*
1412  * last_rcvd & last_committed update callbacks
1413  */
1414 static int tgt_last_rcvd_update(const struct lu_env *env, struct lu_target *tgt,
1415                                 struct dt_object *obj, __u64 opdata,
1416                                 struct thandle *th, struct ptlrpc_request *req)
1417 {
1418         struct tgt_thread_info  *tti = tgt_th_info(env);
1419         struct tgt_session_info *tsi = tgt_ses_info(env);
1420         struct obd_export *exp = tsi->tsi_exp;
1421         struct tg_export_data *ted;
1422         __u64 *transno_p;
1423         bool nolcd = false;
1424         int rc = 0;
1425
1426         ENTRY;
1427
1428
1429         LASSERT(exp != NULL);
1430         ted = &exp->exp_target_data;
1431
1432         /* Some clients don't support recovery, and they don't have last_rcvd
1433          * client data:
1434          * 1. lightweight clients.
1435          * 2. local clients on MDS which doesn't enable "localrecov".
1436          * 3. OFD connect may cause transaction before export has last_rcvd
1437          *    slot.
1438          */
1439         if (ted->ted_lr_idx < 0)
1440                 nolcd = true;
1441
1442         if (req != NULL)
1443                 tti->tti_transno = lustre_msg_get_transno(req->rq_reqmsg);
1444         else
1445                 /* From update replay, tti_transno should be set already */
1446                 LASSERT(tti->tti_transno != 0);
1447
1448         spin_lock(&tgt->lut_translock);
1449         if (th->th_result != 0) {
1450                 if (tti->tti_transno != 0) {
1451                         CERROR("%s: replay transno %llu failed: rc = %d\n",
1452                                tgt_name(tgt), tti->tti_transno, th->th_result);
1453                 }
1454         } else if (tti->tti_transno == 0) {
1455                 tti->tti_transno = ++tgt->lut_last_transno;
1456         } else {
1457                 /* should be replay */
1458                 if (tti->tti_transno > tgt->lut_last_transno)
1459                         tgt->lut_last_transno = tti->tti_transno;
1460         }
1461         spin_unlock(&tgt->lut_translock);
1462
1463         /** VBR: set new versions */
1464         if (th->th_result == 0 && obj != NULL) {
1465                 struct dt_object *dto = dt_object_locate(obj, th->th_dev);
1466                 dt_version_set(env, dto, tti->tti_transno, th);
1467         }
1468
1469         /* filling reply data */
1470         CDEBUG(D_INODE, "transno = %llu, last_committed = %llu\n",
1471                tti->tti_transno, tgt->lut_obd->obd_last_committed);
1472
1473         if (req != NULL) {
1474                 req->rq_transno = tti->tti_transno;
1475                 lustre_msg_set_transno(req->rq_repmsg, tti->tti_transno);
1476         }
1477
1478         /* if can't add callback, do sync write */
1479         th->th_sync |= !!tgt_last_commit_cb_add(th, tgt, exp, tti->tti_transno);
1480
1481         if (nolcd) {
1482                 /* store transno in the last_rcvd header */
1483                 spin_lock(&tgt->lut_translock);
1484                 if (tti->tti_transno > tgt->lut_lsd.lsd_last_transno) {
1485                         tgt->lut_lsd.lsd_last_transno = tti->tti_transno;
1486                         spin_unlock(&tgt->lut_translock);
1487                         /* Although current connection doesn't have slot
1488                          * in the last_rcvd, we still want to maintain
1489                          * the in-memory lsd_client_data structure in order to
1490                          * properly handle reply reconstruction. */
1491                         rc = tgt_server_data_write(env, tgt, th);
1492                 } else {
1493                         spin_unlock(&tgt->lut_translock);
1494                 }
1495         } else if (ted->ted_lr_off == 0) {
1496                 CERROR("%s: client idx %d has offset %lld\n",
1497                        tgt_name(tgt), ted->ted_lr_idx, ted->ted_lr_off);
1498                 RETURN(-EINVAL);
1499         }
1500
1501         /* Target that supports multiple reply data */
1502         if (tgt_is_multimodrpcs_client(exp)) {
1503                 return tgt_mk_reply_data(env, tgt, ted, req, opdata, th,
1504                                          !!(req != NULL), tti->tti_transno);
1505         }
1506
1507         /* Enough for update replay, let's return */
1508         if (req == NULL)
1509                 RETURN(rc);
1510
1511         mutex_lock(&ted->ted_lcd_lock);
1512         LASSERT(ergo(tti->tti_transno == 0, th->th_result != 0));
1513         if (lustre_msg_get_opc(req->rq_reqmsg) == MDS_CLOSE) {
1514                 transno_p = &ted->ted_lcd->lcd_last_close_transno;
1515                 ted->ted_lcd->lcd_last_close_xid = req->rq_xid;
1516                 ted->ted_lcd->lcd_last_close_result = th->th_result;
1517         } else {
1518                 /* VBR: save versions in last_rcvd for reconstruct. */
1519                 __u64 *pre_versions = lustre_msg_get_versions(req->rq_repmsg);
1520
1521                 if (pre_versions) {
1522                         ted->ted_lcd->lcd_pre_versions[0] = pre_versions[0];
1523                         ted->ted_lcd->lcd_pre_versions[1] = pre_versions[1];
1524                         ted->ted_lcd->lcd_pre_versions[2] = pre_versions[2];
1525                         ted->ted_lcd->lcd_pre_versions[3] = pre_versions[3];
1526                 }
1527                 transno_p = &ted->ted_lcd->lcd_last_transno;
1528                 ted->ted_lcd->lcd_last_xid = req->rq_xid;
1529                 ted->ted_lcd->lcd_last_result = th->th_result;
1530                 /* XXX: lcd_last_data is __u32 but intent_dispostion is __u64,
1531                  * see struct ldlm_reply->lock_policy_res1; */
1532                 ted->ted_lcd->lcd_last_data = opdata;
1533         }
1534
1535         /* Update transno in slot only if non-zero number, i.e. no errors */
1536         if (likely(tti->tti_transno != 0)) {
1537                 /* Don't overwrite bigger transaction number with lower one.
1538                  * That is not sign of problem in all cases, but in any case
1539                  * this value should be monotonically increased only. */
1540                 if (*transno_p > tti->tti_transno) {
1541                         if (!tgt->lut_no_reconstruct) {
1542                                 CERROR("%s: trying to overwrite bigger transno:"
1543                                        "on-disk: %llu, new: %llu replay: "
1544                                        "%d. See LU-617.\n", tgt_name(tgt),
1545                                        *transno_p, tti->tti_transno,
1546                                        req_is_replay(req));
1547                                 if (req_is_replay(req)) {
1548                                         spin_lock(&req->rq_export->exp_lock);
1549                                         req->rq_export->exp_vbr_failed = 1;
1550                                         spin_unlock(&req->rq_export->exp_lock);
1551                                 }
1552                                 mutex_unlock(&ted->ted_lcd_lock);
1553                                 RETURN(req_is_replay(req) ? -EOVERFLOW : 0);
1554                         }
1555                 } else {
1556                         *transno_p = tti->tti_transno;
1557                 }
1558         }
1559
1560         if (!nolcd) {
1561                 tti->tti_off = ted->ted_lr_off;
1562                 if (CFS_FAIL_CHECK(OBD_FAIL_TGT_RCVD_EIO))
1563                         rc = -EIO;
1564                 else
1565                         rc = tgt_client_data_write(env, tgt, ted->ted_lcd,
1566                                                    &tti->tti_off, th);
1567                 if (rc < 0) {
1568                         mutex_unlock(&ted->ted_lcd_lock);
1569                         RETURN(rc);
1570                 }
1571         }
1572         mutex_unlock(&ted->ted_lcd_lock);
1573         RETURN(rc);
1574 }
1575
1576 /*
1577  * last_rcvd update for echo client simulation.
1578  * It updates last_rcvd client slot and version of object in
1579  * simple way but with all locks to simulate all drawbacks
1580  */
1581 static int tgt_last_rcvd_update_echo(const struct lu_env *env,
1582                                      struct lu_target *tgt,
1583                                      struct dt_object *obj,
1584                                      struct thandle *th,
1585                                      struct obd_export *exp)
1586 {
1587         struct tgt_thread_info  *tti = tgt_th_info(env);
1588         struct tg_export_data   *ted = &exp->exp_target_data;
1589         int                      rc = 0;
1590
1591         ENTRY;
1592
1593         tti->tti_transno = 0;
1594
1595         spin_lock(&tgt->lut_translock);
1596         if (th->th_result == 0)
1597                 tti->tti_transno = ++tgt->lut_last_transno;
1598         spin_unlock(&tgt->lut_translock);
1599
1600         /** VBR: set new versions */
1601         if (th->th_result == 0 && obj != NULL)
1602                 dt_version_set(env, obj, tti->tti_transno, th);
1603
1604         /* if can't add callback, do sync write */
1605         th->th_sync |= !!tgt_last_commit_cb_add(th, tgt, exp,
1606                                                 tti->tti_transno);
1607
1608         LASSERT(ted->ted_lr_off > 0);
1609
1610         mutex_lock(&ted->ted_lcd_lock);
1611         LASSERT(ergo(tti->tti_transno == 0, th->th_result != 0));
1612         ted->ted_lcd->lcd_last_transno = tti->tti_transno;
1613         ted->ted_lcd->lcd_last_result = th->th_result;
1614
1615         tti->tti_off = ted->ted_lr_off;
1616         rc = tgt_client_data_write(env, tgt, ted->ted_lcd, &tti->tti_off, th);
1617         mutex_unlock(&ted->ted_lcd_lock);
1618         RETURN(rc);
1619 }
1620
1621 static int tgt_clients_data_init(const struct lu_env *env,
1622                                  struct lu_target *tgt,
1623                                  unsigned long last_size)
1624 {
1625         struct obd_device       *obd = tgt->lut_obd;
1626         struct lr_server_data   *lsd = &tgt->lut_lsd;
1627         struct lsd_client_data  *lcd = NULL;
1628         struct tg_export_data   *ted;
1629         int                      cl_idx;
1630         int                      rc = 0;
1631         loff_t                   off = lsd->lsd_client_start;
1632         __u32                    generation = 0;
1633         struct cfs_hash         *hash = NULL;
1634
1635         ENTRY;
1636
1637         if (tgt->lut_bottom->dd_rdonly)
1638                 RETURN(0);
1639
1640         BUILD_BUG_ON(offsetof(struct lsd_client_data, lcd_padding) +
1641                      sizeof(lcd->lcd_padding) != LR_CLIENT_SIZE);
1642
1643         OBD_ALLOC_PTR(lcd);
1644         if (lcd == NULL)
1645                 RETURN(-ENOMEM);
1646
1647         hash = cfs_hash_getref(tgt->lut_obd->obd_gen_hash);
1648         if (hash == NULL)
1649                 GOTO(err_out, rc = -ENODEV);
1650
1651         for (cl_idx = 0; off < last_size; cl_idx++) {
1652                 struct obd_export       *exp;
1653                 __u64                    last_transno;
1654
1655                 /* Don't assume off is incremented properly by
1656                  * read_record(), in case sizeof(*lcd)
1657                  * isn't the same as fsd->lsd_client_size.  */
1658                 off = lsd->lsd_client_start + cl_idx * lsd->lsd_client_size;
1659                 rc = tgt_client_data_read(env, tgt, lcd, &off, cl_idx);
1660                 if (rc) {
1661                         CERROR("%s: error reading last_rcvd %s idx %d off "
1662                                "%llu: rc = %d\n", tgt_name(tgt), LAST_RCVD,
1663                                cl_idx, off, rc);
1664                         rc = 0;
1665                         break; /* read error shouldn't cause startup to fail */
1666                 }
1667
1668                 if (lcd->lcd_uuid[0] == '\0') {
1669                         CDEBUG(D_INFO, "skipping zeroed client at offset %d\n",
1670                                cl_idx);
1671                         continue;
1672                 }
1673
1674                 last_transno = lcd_last_transno(lcd);
1675
1676                 /* These exports are cleaned up by disconnect, so they
1677                  * need to be set up like real exports as connect does.
1678                  */
1679                 CDEBUG(D_HA, "RCVRNG CLIENT uuid: %s idx: %d lr: %llu"
1680                        " srv lr: %llu lx: %llu gen %u\n", lcd->lcd_uuid,
1681                        cl_idx, last_transno, lsd->lsd_last_transno,
1682                        lcd_last_xid(lcd), lcd->lcd_generation);
1683
1684                 exp = class_new_export(obd, (struct obd_uuid *)lcd->lcd_uuid);
1685                 if (IS_ERR(exp)) {
1686                         if (PTR_ERR(exp) == -EALREADY) {
1687                                 /* export already exists, zero out this one */
1688                                 CERROR("%s: Duplicate export %s!\n",
1689                                        tgt_name(tgt), lcd->lcd_uuid);
1690                                 continue;
1691                         }
1692                         GOTO(err_out, rc = PTR_ERR(exp));
1693                 }
1694
1695                 ted = &exp->exp_target_data;
1696                 *ted->ted_lcd = *lcd;
1697
1698                 rc = tgt_client_add(env, exp, cl_idx);
1699                 LASSERTF(rc == 0, "rc = %d\n", rc); /* can't fail existing */
1700                 /* VBR: set export last committed version */
1701                 exp->exp_last_committed = last_transno;
1702                 spin_lock(&exp->exp_lock);
1703                 exp->exp_connecting = 0;
1704                 exp->exp_in_recovery = 0;
1705                 spin_unlock(&exp->exp_lock);
1706                 atomic_inc(&obd->obd_max_recoverable_clients);
1707
1708                 if (tgt_is_multimodrpcs_record(tgt, lcd)) {
1709                         atomic_inc(&tgt->lut_num_clients);
1710
1711                         /* compute the highest valid client generation */
1712                         generation = max(generation, lcd->lcd_generation);
1713                         /* fill client_generation <-> export hash table */
1714                         rc = cfs_hash_add_unique(hash, &lcd->lcd_generation,
1715                                                  &exp->exp_gen_hash);
1716                         if (rc != 0) {
1717                                 CERROR("%s: duplicate export for client "
1718                                        "generation %u\n",
1719                                        tgt_name(tgt), lcd->lcd_generation);
1720                                 class_export_put(exp);
1721                                 GOTO(err_out, rc);
1722                         }
1723                 }
1724
1725                 class_export_put(exp);
1726
1727                 rc = rev_import_init(exp);
1728                 if (rc != 0) {
1729                         class_unlink_export(exp);
1730                         GOTO(err_out, rc);
1731                 }
1732
1733                 /* Need to check last_rcvd even for duplicated exports. */
1734                 CDEBUG(D_OTHER, "client at idx %d has last_transno = %llu\n",
1735                        cl_idx, last_transno);
1736
1737                 spin_lock(&tgt->lut_translock);
1738                 tgt->lut_last_transno = max(last_transno,
1739                                             tgt->lut_last_transno);
1740                 spin_unlock(&tgt->lut_translock);
1741         }
1742
1743         /* record highest valid client generation */
1744         atomic_set(&tgt->lut_client_generation, generation);
1745
1746 err_out:
1747         if (hash != NULL)
1748                 cfs_hash_putref(hash);
1749         OBD_FREE_PTR(lcd);
1750         RETURN(rc);
1751 }
1752
1753 struct server_compat_data {
1754         __u32 rocompat;
1755         __u32 incompat;
1756         __u32 rocinit;
1757         __u32 incinit;
1758 };
1759
1760 static struct server_compat_data tgt_scd[] = {
1761         [LDD_F_SV_TYPE_MDT] = {
1762                 .rocompat = OBD_ROCOMPAT_LOVOBJID,
1763                 .incompat = OBD_INCOMPAT_MDT | OBD_INCOMPAT_COMMON_LR |
1764                             OBD_INCOMPAT_FID | OBD_INCOMPAT_IAM_DIR |
1765                             OBD_INCOMPAT_LMM_VER | OBD_INCOMPAT_MULTI_OI |
1766                             OBD_INCOMPAT_MULTI_RPCS,
1767                 .rocinit = OBD_ROCOMPAT_LOVOBJID,
1768                 .incinit = OBD_INCOMPAT_MDT | OBD_INCOMPAT_COMMON_LR |
1769                            OBD_INCOMPAT_MULTI_OI,
1770         },
1771         [LDD_F_SV_TYPE_OST] = {
1772                 .rocompat = OBD_ROCOMPAT_IDX_IN_IDIF,
1773                 .incompat = OBD_INCOMPAT_OST | OBD_INCOMPAT_COMMON_LR |
1774                             OBD_INCOMPAT_FID,
1775                 .rocinit = OBD_ROCOMPAT_IDX_IN_IDIF,
1776                 .incinit = OBD_INCOMPAT_OST | OBD_INCOMPAT_COMMON_LR,
1777         }
1778 };
1779
1780 int tgt_server_data_init(const struct lu_env *env, struct lu_target *tgt)
1781 {
1782         struct tgt_thread_info          *tti = tgt_th_info(env);
1783         struct lr_server_data           *lsd = &tgt->lut_lsd;
1784         unsigned long                    last_rcvd_size;
1785         __u32                            index;
1786         int                              rc, type;
1787
1788         rc = dt_attr_get(env, tgt->lut_last_rcvd, &tti->tti_attr);
1789         if (rc)
1790                 RETURN(rc);
1791
1792         last_rcvd_size = (unsigned long)tti->tti_attr.la_size;
1793
1794         /* ensure padding in the struct is the correct size */
1795         BUILD_BUG_ON(offsetof(struct lr_server_data, lsd_padding) +
1796                      sizeof(lsd->lsd_padding) != LR_SERVER_SIZE);
1797
1798         rc = server_name2index(tgt_name(tgt), &index, NULL);
1799         if (rc < 0) {
1800                 CERROR("%s: Can not get index from name: rc = %d\n",
1801                        tgt_name(tgt), rc);
1802                 RETURN(rc);
1803         }
1804         /* server_name2index() returns type */
1805         type = rc;
1806         if (type != LDD_F_SV_TYPE_MDT && type != LDD_F_SV_TYPE_OST) {
1807                 CERROR("%s: unknown target type %x\n", tgt_name(tgt), type);
1808                 RETURN(-EINVAL);
1809         }
1810
1811         /* last_rcvd on OST doesn't provide reconstruct support because there
1812          * may be up to 8 in-flight write requests per single slot in
1813          * last_rcvd client data
1814          */
1815         tgt->lut_no_reconstruct = (type == LDD_F_SV_TYPE_OST);
1816
1817         if (last_rcvd_size == 0) {
1818                 LCONSOLE_WARN("%s: new disk, initializing\n", tgt_name(tgt));
1819
1820                 memcpy(lsd->lsd_uuid, tgt->lut_obd->obd_uuid.uuid,
1821                        sizeof(lsd->lsd_uuid));
1822                 lsd->lsd_last_transno = 0;
1823                 lsd->lsd_mount_count = 0;
1824                 lsd->lsd_server_size = LR_SERVER_SIZE;
1825                 lsd->lsd_client_start = LR_CLIENT_START;
1826                 lsd->lsd_client_size = LR_CLIENT_SIZE;
1827                 lsd->lsd_subdir_count = OBJ_SUBDIR_COUNT;
1828                 lsd->lsd_osd_index = index;
1829                 lsd->lsd_feature_rocompat = tgt_scd[type].rocinit;
1830                 lsd->lsd_feature_incompat = tgt_scd[type].incinit;
1831         } else {
1832                 rc = tgt_server_data_read(env, tgt);
1833                 if (rc) {
1834                         CERROR("%s: error reading LAST_RCVD: rc= %d\n",
1835                                tgt_name(tgt), rc);
1836                         RETURN(rc);
1837                 }
1838                 if (strcmp(lsd->lsd_uuid, tgt->lut_obd->obd_uuid.uuid)) {
1839                         if (tgt->lut_bottom->dd_rdonly) {
1840                                 /* Such difference may be caused by mounting
1841                                  * up snapshot with new fsname under rd_only
1842                                  * mode. But even if it was NOT, it will not
1843                                  * damage the system because of "rd_only". */
1844                                 memcpy(lsd->lsd_uuid,
1845                                        tgt->lut_obd->obd_uuid.uuid,
1846                                        sizeof(lsd->lsd_uuid));
1847                         } else {
1848                                 LCONSOLE_ERROR_MSG(0x157, "Trying to start "
1849                                                    "OBD %s using the wrong "
1850                                                    "disk %s. Were the /dev/ "
1851                                                    "assignments rearranged?\n",
1852                                                    tgt->lut_obd->obd_uuid.uuid,
1853                                                    lsd->lsd_uuid);
1854                                 RETURN(-EINVAL);
1855                         }
1856                 }
1857
1858                 if (lsd->lsd_osd_index != index) {
1859                         LCONSOLE_ERROR_MSG(0x157,
1860                                            "%s: index %d in last rcvd is different with the index %d in config log, It might be disk corruption!\n",
1861                                            tgt_name(tgt),
1862                                            lsd->lsd_osd_index, index);
1863                         RETURN(-EINVAL);
1864                 }
1865         }
1866
1867         if (lsd->lsd_feature_incompat & ~tgt_scd[type].incompat) {
1868                 CERROR("%s: unsupported incompat filesystem feature(s) %x\n",
1869                        tgt_name(tgt),
1870                        lsd->lsd_feature_incompat & ~tgt_scd[type].incompat);
1871                 RETURN(-EINVAL);
1872         }
1873
1874         if (type == LDD_F_SV_TYPE_MDT)
1875                 lsd->lsd_feature_incompat |= OBD_INCOMPAT_FID;
1876
1877         if (lsd->lsd_feature_rocompat & ~tgt_scd[type].rocompat) {
1878                 CERROR("%s: unsupported read-only filesystem feature(s) %x\n",
1879                        tgt_name(tgt),
1880                        lsd->lsd_feature_rocompat & ~tgt_scd[type].rocompat);
1881                 RETURN(-EINVAL);
1882         }
1883         /** Interop: evict all clients at first boot with 1.8 last_rcvd */
1884         if (type == LDD_F_SV_TYPE_MDT &&
1885             !(lsd->lsd_feature_compat & OBD_COMPAT_20)) {
1886                 if (last_rcvd_size > lsd->lsd_client_start) {
1887                         LCONSOLE_WARN("%s: mounting at first time on 1.8 FS, "
1888                                       "remove all clients for interop needs\n",
1889                                       tgt_name(tgt));
1890                         rc = tgt_truncate_last_rcvd(env, tgt,
1891                                                     lsd->lsd_client_start);
1892                         if (rc)
1893                                 RETURN(rc);
1894                         last_rcvd_size = lsd->lsd_client_start;
1895                 }
1896                 /** set 2.0 flag to upgrade/downgrade between 1.8 and 2.0 */
1897                 lsd->lsd_feature_compat |= OBD_COMPAT_20;
1898         }
1899
1900         spin_lock(&tgt->lut_translock);
1901         tgt->lut_last_transno = lsd->lsd_last_transno;
1902         spin_unlock(&tgt->lut_translock);
1903
1904         lsd->lsd_mount_count++;
1905
1906         CDEBUG(D_INODE, "=======,=BEGIN DUMPING LAST_RCVD========\n");
1907         CDEBUG(D_INODE, "%s: server last_transno: %llu\n",
1908                tgt_name(tgt), tgt->lut_last_transno);
1909         CDEBUG(D_INODE, "%s: server mount_count: %llu\n",
1910                tgt_name(tgt), lsd->lsd_mount_count);
1911         CDEBUG(D_INODE, "%s: server data size: %u\n",
1912                tgt_name(tgt), lsd->lsd_server_size);
1913         CDEBUG(D_INODE, "%s: per-client data start: %u\n",
1914                tgt_name(tgt), lsd->lsd_client_start);
1915         CDEBUG(D_INODE, "%s: per-client data size: %u\n",
1916                tgt_name(tgt), lsd->lsd_client_size);
1917         CDEBUG(D_INODE, "%s: last_rcvd size: %lu\n",
1918                tgt_name(tgt), last_rcvd_size);
1919         CDEBUG(D_INODE, "%s: server subdir_count: %u\n",
1920                tgt_name(tgt), lsd->lsd_subdir_count);
1921         CDEBUG(D_INODE, "%s: last_rcvd clients: %lu\n", tgt_name(tgt),
1922                last_rcvd_size <= lsd->lsd_client_start ? 0 :
1923                (last_rcvd_size - lsd->lsd_client_start) /
1924                 lsd->lsd_client_size);
1925         CDEBUG(D_INODE, "========END DUMPING LAST_RCVD========\n");
1926
1927         if (lsd->lsd_server_size == 0 || lsd->lsd_client_start == 0 ||
1928             lsd->lsd_client_size == 0) {
1929                 CERROR("%s: bad last_rcvd contents!\n", tgt_name(tgt));
1930                 RETURN(-EINVAL);
1931         }
1932
1933         if (!tgt->lut_obd->obd_replayable)
1934                 CWARN("%s: recovery support OFF\n", tgt_name(tgt));
1935
1936         rc = tgt_clients_data_init(env, tgt, last_rcvd_size);
1937         if (rc < 0)
1938                 GOTO(err_client, rc);
1939
1940         spin_lock(&tgt->lut_translock);
1941         /* obd_last_committed is used for compatibility
1942          * with other lustre recovery code */
1943         tgt->lut_obd->obd_last_committed = tgt->lut_last_transno;
1944         spin_unlock(&tgt->lut_translock);
1945
1946         obd2obt(tgt->lut_obd)->obt_mount_count = lsd->lsd_mount_count;
1947         obd2obt(tgt->lut_obd)->obt_instance = (__u32)lsd->lsd_mount_count;
1948
1949         /* save it, so mount count and last_transno is current */
1950         rc = tgt_server_data_update(env, tgt, 0);
1951         if (rc < 0)
1952                 GOTO(err_client, rc);
1953
1954         RETURN(0);
1955
1956 err_client:
1957         class_disconnect_exports(tgt->lut_obd);
1958         return rc;
1959 }
1960
1961 /* add credits for last_rcvd update */
1962 int tgt_txn_start_cb(const struct lu_env *env, struct thandle *th,
1963                      void *cookie)
1964 {
1965         struct lu_target        *tgt = cookie;
1966         struct tgt_session_info *tsi;
1967         struct tgt_thread_info  *tti = tgt_th_info(env);
1968         struct dt_object        *dto;
1969         int                      rc;
1970
1971         /* For readonly case, the caller should have got failure
1972          * when start the transaction. If the logic comes here,
1973          * there must be something wrong. */
1974         if (unlikely(tgt->lut_bottom->dd_rdonly)) {
1975                 dump_stack();
1976                 LBUG();
1977         }
1978
1979         /* if there is no session, then this transaction is not result of
1980          * request processing but some local operation */
1981         if (env->le_ses == NULL)
1982                 return 0;
1983
1984         LASSERT(tgt->lut_last_rcvd);
1985         tsi = tgt_ses_info(env);
1986         /* OFD may start transaction without export assigned */
1987         if (tsi->tsi_exp == NULL)
1988                 return 0;
1989
1990         if (tgt_is_multimodrpcs_client(tsi->tsi_exp)) {
1991                 /*
1992                  * Use maximum possible file offset for declaration to ensure
1993                  * ZFS will reserve enough credits for a write anywhere in this
1994                  * file, since we don't know where in the file the write will be
1995                  * because a replay slot has not been assigned.  This should be
1996                  * replaced by dmu_tx_hold_append() when available.
1997                  */
1998                 tti->tti_buf.lb_buf = NULL;
1999                 tti->tti_buf.lb_len = sizeof(struct lsd_reply_data);
2000                 dto = dt_object_locate(tgt->lut_reply_data, th->th_dev);
2001                 rc = dt_declare_record_write(env, dto, &tti->tti_buf, -1, th);
2002                 if (rc)
2003                         return rc;
2004         } else {
2005                 dto = dt_object_locate(tgt->lut_last_rcvd, th->th_dev);
2006                 tti_buf_lcd(tti);
2007                 tti->tti_off = tsi->tsi_exp->exp_target_data.ted_lr_off;
2008                 rc = dt_declare_record_write(env, dto, &tti->tti_buf,
2009                                              tti->tti_off, th);
2010                 if (rc)
2011                         return rc;
2012         }
2013
2014         if (tsi->tsi_vbr_obj != NULL &&
2015             !lu_object_remote(&tsi->tsi_vbr_obj->do_lu)) {
2016                 dto = dt_object_locate(tsi->tsi_vbr_obj, th->th_dev);
2017                 rc = dt_declare_version_set(env, dto, th);
2018         }
2019
2020         return rc;
2021 }
2022
2023 /* Update last_rcvd records with latests transaction data */
2024 int tgt_txn_stop_cb(const struct lu_env *env, struct thandle *th,
2025                     void *cookie)
2026 {
2027         struct lu_target        *tgt = cookie;
2028         struct tgt_session_info *tsi;
2029         struct tgt_thread_info  *tti = tgt_th_info(env);
2030         struct dt_object        *obj = NULL;
2031         int                      rc;
2032         bool                     echo_client;
2033
2034         if (env->le_ses == NULL)
2035                 return 0;
2036
2037         tsi = tgt_ses_info(env);
2038         /* OFD may start transaction without export assigned */
2039         if (tsi->tsi_exp == NULL)
2040                 return 0;
2041
2042         echo_client = (tgt_ses_req(tsi) == NULL && tsi->tsi_xid == 0);
2043
2044         if (tsi->tsi_has_trans && !echo_client && !tsi->tsi_batch_env) {
2045                 if (!tsi->tsi_mult_trans) {
2046                         CDEBUG(D_HA, "More than one transaction %llu\n",
2047                                tti->tti_transno);
2048                         /**
2049                          * if RPC handler sees unexpected multiple last_rcvd
2050                          * updates with transno, then it is better to return
2051                          * the latest transaction number to the client.
2052                          * In that case replay may fail if part of operation
2053                          * was committed and can't be re-applied easily. But
2054                          * that is better than report the first transno, in
2055                          * which case partially committed operation would be
2056                          * considered as finished so never replayed causing
2057                          * data loss.
2058                          */
2059                 }
2060                 /* we need new transno to be assigned */
2061                 tti->tti_transno = 0;
2062         }
2063
2064         if (!th->th_result)
2065                 tsi->tsi_has_trans++;
2066
2067         if (tsi->tsi_vbr_obj != NULL &&
2068             !lu_object_remote(&tsi->tsi_vbr_obj->do_lu)) {
2069                 obj = tsi->tsi_vbr_obj;
2070         }
2071
2072         if (unlikely(echo_client)) /* echo client special case */
2073                 rc = tgt_last_rcvd_update_echo(env, tgt, obj, th,
2074                                                tsi->tsi_exp);
2075         else
2076                 rc = tgt_last_rcvd_update(env, tgt, obj, tsi->tsi_opdata, th,
2077                                           tgt_ses_req(tsi));
2078         return rc;
2079 }
2080
2081 int tgt_reply_data_init(const struct lu_env *env, struct lu_target *tgt)
2082 {
2083         struct tgt_thread_info  *tti = tgt_th_info(env);
2084         struct lsd_reply_data   *lrd = &tti->tti_lrd;
2085         unsigned long            reply_data_size;
2086         int                      rc;
2087         struct lsd_reply_header *lrh = NULL;
2088         struct tg_reply_data    *trd = NULL;
2089         int                      idx;
2090         loff_t                   off;
2091         struct cfs_hash         *hash = NULL;
2092         struct obd_export       *exp;
2093         struct tg_export_data   *ted;
2094         int                      reply_data_recovered = 0;
2095
2096         rc = dt_attr_get(env, tgt->lut_reply_data, &tti->tti_attr);
2097         if (rc)
2098                 GOTO(out, rc);
2099         reply_data_size = (unsigned long)tti->tti_attr.la_size;
2100
2101         OBD_ALLOC_PTR(lrh);
2102         if (lrh == NULL)
2103                 GOTO(out, rc = -ENOMEM);
2104
2105         if (reply_data_size == 0) {
2106                 CDEBUG(D_INFO, "%s: new reply_data file, initializing\n",
2107                        tgt_name(tgt));
2108                 lrh->lrh_magic = LRH_MAGIC;
2109                 lrh->lrh_header_size = sizeof(struct lsd_reply_header);
2110                 lrh->lrh_reply_size = sizeof(struct lsd_reply_data);
2111                 rc = tgt_reply_header_write(env, tgt, lrh);
2112                 if (rc) {
2113                         CERROR("%s: error writing %s: rc = %d\n",
2114                                tgt_name(tgt), REPLY_DATA, rc);
2115                         GOTO(out, rc);
2116                 }
2117         } else {
2118                 rc = tgt_reply_header_read(env, tgt, lrh);
2119                 if (rc) {
2120                         CERROR("%s: error reading %s: rc = %d\n",
2121                                tgt_name(tgt), REPLY_DATA, rc);
2122                         GOTO(out, rc);
2123                 }
2124                 if (lrh->lrh_magic != LRH_MAGIC ||
2125                     lrh->lrh_header_size != sizeof(struct lsd_reply_header) ||
2126                     lrh->lrh_reply_size != sizeof(struct lsd_reply_data)) {
2127                         CERROR("%s: invalid header in %s\n",
2128                                tgt_name(tgt), REPLY_DATA);
2129                         GOTO(out, rc = -EINVAL);
2130                 }
2131
2132                 hash = cfs_hash_getref(tgt->lut_obd->obd_gen_hash);
2133                 if (hash == NULL)
2134                         GOTO(out, rc = -ENODEV);
2135
2136                 OBD_ALLOC_PTR(trd);
2137                 if (trd == NULL)
2138                         GOTO(out, rc = -ENOMEM);
2139
2140                 /* Load reply_data from disk */
2141                 for (idx = 0, off = sizeof(struct lsd_reply_header);
2142                      off < reply_data_size;
2143                      idx++, off += sizeof(struct lsd_reply_data)) {
2144                         rc = tgt_reply_data_read(env, tgt, lrd, off);
2145                         if (rc) {
2146                                 CERROR("%s: error reading %s: rc = %d\n",
2147                                        tgt_name(tgt), REPLY_DATA, rc);
2148                                 GOTO(out, rc);
2149                         }
2150
2151                         exp = cfs_hash_lookup(hash, &lrd->lrd_client_gen);
2152                         if (exp == NULL) {
2153                                 /* old reply data from a disconnected client */
2154                                 continue;
2155                         }
2156                         ted = &exp->exp_target_data;
2157                         mutex_lock(&ted->ted_lcd_lock);
2158
2159                         /* create in-memory reply_data and link it to
2160                          * target export's reply list */
2161                         rc = tgt_set_reply_slot(tgt, idx);
2162                         if (rc != 0) {
2163                                 mutex_unlock(&ted->ted_lcd_lock);
2164                                 GOTO(out, rc);
2165                         }
2166                         trd->trd_reply = *lrd;
2167                         trd->trd_pre_versions[0] = 0;
2168                         trd->trd_pre_versions[1] = 0;
2169                         trd->trd_pre_versions[2] = 0;
2170                         trd->trd_pre_versions[3] = 0;
2171                         trd->trd_index = idx;
2172                         trd->trd_tag = 0;
2173                         fid_zero(&trd->trd_object);
2174                         list_add(&trd->trd_list, &ted->ted_reply_list);
2175                         ted->ted_reply_cnt++;
2176                         if (ted->ted_reply_cnt > ted->ted_reply_max)
2177                                 ted->ted_reply_max = ted->ted_reply_cnt;
2178
2179                         CDEBUG(D_HA, "%s: restore reply %p: xid %llu, "
2180                                "transno %llu, client gen %u, slot idx %d\n",
2181                                tgt_name(tgt), trd, lrd->lrd_xid,
2182                                lrd->lrd_transno, lrd->lrd_client_gen,
2183                                trd->trd_index);
2184
2185                         /* update export last committed transation */
2186                         exp->exp_last_committed = max(exp->exp_last_committed,
2187                                                       lrd->lrd_transno);
2188                         /* Update lcd_last_transno as well for check in
2189                          * tgt_release_reply_data() or the latest client
2190                          * transno can be lost.
2191                          */
2192                         ted->ted_lcd->lcd_last_transno =
2193                                 max(ted->ted_lcd->lcd_last_transno,
2194                                     exp->exp_last_committed);
2195
2196                         mutex_unlock(&ted->ted_lcd_lock);
2197                         class_export_put(exp);
2198
2199                         /* update target last committed transaction */
2200                         spin_lock(&tgt->lut_translock);
2201                         tgt->lut_last_transno = max(tgt->lut_last_transno,
2202                                                     lrd->lrd_transno);
2203                         spin_unlock(&tgt->lut_translock);
2204
2205                         reply_data_recovered++;
2206
2207                         OBD_ALLOC_PTR(trd);
2208                         if (trd == NULL)
2209                                 GOTO(out, rc = -ENOMEM);
2210                 }
2211                 CDEBUG(D_INFO, "%s: %d reply data have been recovered\n",
2212                        tgt_name(tgt), reply_data_recovered);
2213         }
2214
2215         spin_lock(&tgt->lut_translock);
2216         /* obd_last_committed is used for compatibility
2217          * with other lustre recovery code */
2218         tgt->lut_obd->obd_last_committed = tgt->lut_last_transno;
2219         spin_unlock(&tgt->lut_translock);
2220
2221         rc = 0;
2222
2223 out:
2224         if (hash != NULL)
2225                 cfs_hash_putref(hash);
2226         if (trd != NULL)
2227                 OBD_FREE_PTR(trd);
2228         if (lrh != NULL)
2229                 OBD_FREE_PTR(lrh);
2230         return rc;
2231 }
2232
2233 static int tgt_check_lookup_req(struct ptlrpc_request *req, int lookup,
2234                                 struct tg_reply_data *trd)
2235 {
2236         struct tg_export_data *ted = &req->rq_export->exp_target_data;
2237         struct lu_target *lut = class_exp2tgt(req->rq_export);
2238         __u16 tag = lustre_msg_get_tag(req->rq_reqmsg);
2239         int rc = 0;
2240         struct tg_reply_data *reply;
2241         bool check_increasing;
2242
2243         if (tag == 0)
2244                 return 0;
2245
2246         check_increasing = tgt_is_increasing_xid_client(req->rq_export) &&
2247                            !(lustre_msg_get_flags(req->rq_reqmsg) & MSG_REPLAY);
2248         if (!lookup && !check_increasing)
2249                 return 0;
2250
2251         list_for_each_entry(reply, &ted->ted_reply_list, trd_list) {
2252                 if (lookup && reply->trd_reply.lrd_xid == req->rq_xid) {
2253                         rc = 1;
2254                         if (trd != NULL)
2255                                 *trd = *reply;
2256                         break;
2257                 } else if (check_increasing && reply->trd_tag == tag &&
2258                            reply->trd_reply.lrd_xid > req->rq_xid) {
2259                         rc = -EPROTO;
2260                         CERROR("%s: busy tag=%u req_xid=%llu, trd=%p: xid=%llu transno=%llu client_gen=%u slot_idx=%d: rc = %d\n",
2261                                tgt_name(lut), tag, req->rq_xid, trd,
2262                                reply->trd_reply.lrd_xid,
2263                                reply->trd_reply.lrd_transno,
2264                                reply->trd_reply.lrd_client_gen,
2265                                reply->trd_index, rc);
2266                         break;
2267                 }
2268         }
2269
2270         return rc;
2271 }
2272
2273 /* Look for a reply data matching specified request @req
2274  * A copy is returned in @trd if the pointer is not NULL
2275  */
2276 int tgt_lookup_reply(struct ptlrpc_request *req, struct tg_reply_data *trd)
2277 {
2278         struct tg_export_data *ted = &req->rq_export->exp_target_data;
2279         int found = 0;
2280         bool not_replay = !(lustre_msg_get_flags(req->rq_reqmsg) & MSG_REPLAY);
2281
2282         mutex_lock(&ted->ted_lcd_lock);
2283         if (not_replay && req->rq_xid <= req->rq_export->exp_last_xid) {
2284                 /* A check for the last_xid is needed here in case there is
2285                  * no reply data is left in the list. It may happen if another
2286                  * RPC on another slot increased the last_xid between our
2287                  * process_req_last_xid & tgt_lookup_reply calls */
2288                 found = -EPROTO;
2289         } else {
2290                 found = tgt_check_lookup_req(req, 1, trd);
2291         }
2292         mutex_unlock(&ted->ted_lcd_lock);
2293
2294         CDEBUG(D_TRACE, "%s: lookup reply xid %llu, found %d last_xid %llu\n",
2295                tgt_name(class_exp2tgt(req->rq_export)), req->rq_xid, found,
2296                req->rq_export->exp_last_xid);
2297
2298         return found;
2299 }
2300 EXPORT_SYMBOL(tgt_lookup_reply);
2301
2302 int tgt_handle_received_xid(struct obd_export *exp, __u64 rcvd_xid)
2303 {
2304         struct tg_export_data   *ted = &exp->exp_target_data;
2305         struct lu_target        *lut = class_exp2tgt(exp);
2306         struct tg_reply_data    *trd, *tmp;
2307
2308
2309         list_for_each_entry_safe(trd, tmp, &ted->ted_reply_list, trd_list) {
2310                 if (trd->trd_reply.lrd_xid > rcvd_xid)
2311                         continue;
2312                 ted->ted_release_xid++;
2313                 tgt_release_reply_data(lut, ted, trd);
2314         }
2315
2316         return 0;
2317 }
2318
2319 int tgt_handle_tag(struct ptlrpc_request *req)
2320 {
2321         return tgt_check_lookup_req(req, 0, NULL);
2322 }
2323