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.sun.com/software/products/lustre/docs/GPLv2.pdf
  19  *
  20  * Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
  21  * CA 95054 USA or visit www.sun.com if you need additional information or
  22  * have any questions.
  23  *
  24  * GPL HEADER END
  25  */
  26 /*
  27  * Copyright (c) 2009, 2010, Oracle and/or its affiliates. All rights reserved.
  28  * Use is subject to license terms.
  29  *
  30  * Copyright (c) 2011, 2012, Intel Corporation.
  31  */
  32 /*
  33  * This file is part of Lustre, http://www.lustre.org/
  34  * Lustre is a trademark of Sun Microsystems, Inc.
  35  *
  36  * Lustre Unified Target
  37  * These are common function to work with last_received file
  38  *
  39  * Author: Mikhail Pershin <mike.pershin@intel.com>
  40  */
  41 #include <obd.h>
  42 #include <obd_class.h>
  43 #include <lustre_fid.h>
  44
  45 #include "tgt_internal.h"
  46
  47 static inline struct lu_buf *tti_buf_lsd(struct tgt_thread_info *tti)
  48 {
  49         tti->tti_buf.lb_buf = &tti->tti_lsd;
  50         tti->tti_buf.lb_len = sizeof(tti->tti_lsd);
  51         return &tti->tti_buf;
  52 }
  53
  54 static inline struct lu_buf *tti_buf_lcd(struct tgt_thread_info *tti)
  55 {
  56         tti->tti_buf.lb_buf = &tti->tti_lcd;
  57         tti->tti_buf.lb_len = sizeof(tti->tti_lcd);
  58         return &tti->tti_buf;
  59 }
  60
  61 /**
  62  * Allocate in-memory data for client slot related to export.
  63  */
  64 int tgt_client_alloc(struct obd_export *exp)
  65 {
  66         ENTRY;
  67         LASSERT(exp != exp->exp_obd->obd_self_export);
  68
  69         OBD_ALLOC_PTR(exp->exp_target_data.ted_lcd);
  70         if (exp->exp_target_data.ted_lcd == NULL)
  71                 RETURN(-ENOMEM);
  72         /* Mark that slot is not yet valid, 0 doesn't work here */
  73         exp->exp_target_data.ted_lr_idx = -1;
  74         RETURN(0);
  75 }
  76 EXPORT_SYMBOL(tgt_client_alloc);
  77
  78 /**
  79  * Free in-memory data for client slot related to export.
  80  */
  81 void tgt_client_free(struct obd_export *exp)
  82 {
  83         struct tg_export_data   *ted = &exp->exp_target_data;
  84         struct lu_target        *lut = class_exp2tgt(exp);
  85
  86         LASSERT(exp != exp->exp_obd->obd_self_export);
  87
  88         OBD_FREE_PTR(ted->ted_lcd);
  89         ted->ted_lcd = NULL;
  90
  91         /* Slot may be not yet assigned */
  92         if (ted->ted_lr_idx < 0)
  93                 return;
  94         /* Clear bit when lcd is freed */
  95         LASSERT(lut->lut_client_bitmap);
  96         if (!test_and_clear_bit(ted->ted_lr_idx, lut->lut_client_bitmap)) {
  97                 CERROR("%s: client %u bit already clear in bitmap\n",
  98                        exp->exp_obd->obd_name, ted->ted_lr_idx);
  99                 LBUG();
 100         }
 101 }
 102 EXPORT_SYMBOL(tgt_client_free);
 103
 104 int tgt_client_data_read(const struct lu_env *env, struct lu_target *tgt,
 105                          struct lsd_client_data *lcd, loff_t *off, int index)
 106 {
 107         struct tgt_thread_info  *tti = tgt_th_info(env);
 108         int                      rc;
 109
 110         tti_buf_lcd(tti);
 111         rc = dt_record_read(env, tgt->lut_last_rcvd, &tti->tti_buf, off);
 112         if (rc == 0) {
 113                 check_lcd(tgt->lut_obd->obd_name, index, &tti->tti_lcd);
 114                 lcd_le_to_cpu(&tti->tti_lcd, lcd);
 115                 lcd->lcd_last_result = ptlrpc_status_ntoh(lcd->lcd_last_result);
 116                 lcd->lcd_last_close_result =
 117                         ptlrpc_status_ntoh(lcd->lcd_last_close_result);
 118         }
 119
 120         CDEBUG(D_INFO, "%s: read lcd @%lld uuid = %s, last_transno = "LPU64
 121                ", last_xid = "LPU64", last_result = %u, last_data = %u, "
 122                "last_close_transno = "LPU64", last_close_xid = "LPU64", "
 123                "last_close_result = %u, rc = %d\n", tgt->lut_obd->obd_name,
 124                *off, lcd->lcd_uuid, lcd->lcd_last_transno, lcd->lcd_last_xid,
 125                lcd->lcd_last_result, lcd->lcd_last_data,
 126                lcd->lcd_last_close_transno, lcd->lcd_last_close_xid,
 127                lcd->lcd_last_close_result, rc);
 128         return rc;
 129 }
 130 EXPORT_SYMBOL(tgt_client_data_read);
 131
 132 int tgt_client_data_write(const struct lu_env *env, struct lu_target *tgt,
 133                           struct lsd_client_data *lcd, loff_t *off,
 134                           struct thandle *th)
 135 {
 136         struct tgt_thread_info *tti = tgt_th_info(env);
 137
 138         lcd->lcd_last_result = ptlrpc_status_hton(lcd->lcd_last_result);
 139         lcd->lcd_last_close_result =
 140                 ptlrpc_status_hton(lcd->lcd_last_close_result);
 141         lcd_cpu_to_le(lcd, &tti->tti_lcd);
 142         tti_buf_lcd(tti);
 143
 144         return dt_record_write(env, tgt->lut_last_rcvd, &tti->tti_buf, off, th);
 145 }
 146 EXPORT_SYMBOL(tgt_client_data_write);
 147
 148 /**
 149  * Update client data in last_rcvd
 150  */
 151 int tgt_client_data_update(const struct lu_env *env, struct obd_export *exp)
 152 {
 153         struct tg_export_data   *ted = &exp->exp_target_data;
 154         struct lu_target        *tgt = class_exp2tgt(exp);
 155         struct tgt_thread_info  *tti = tgt_th_info(env);
 156         struct thandle          *th;
 157         int                      rc = 0;
 158
 159         ENTRY;
 160
 161         th = dt_trans_create(env, tgt->lut_bottom);
 162         if (IS_ERR(th))
 163                 RETURN(PTR_ERR(th));
 164
 165         rc = dt_declare_record_write(env, tgt->lut_last_rcvd,
 166                                      sizeof(struct lsd_client_data),
 167                                      ted->ted_lr_off, th);
 168         if (rc)
 169                 GOTO(out, rc);
 170
 171         rc = dt_trans_start_local(env, tgt->lut_bottom, th);
 172         if (rc)
 173                 GOTO(out, rc);
 174         /*
 175          * Until this operations will be committed the sync is needed
 176          * for this export. This should be done _after_ starting the
 177          * transaction so that many connecting clients will not bring
 178          * server down with lots of sync writes.
 179          */
 180         rc = tgt_new_client_cb_add(th, exp);
 181         if (rc) {
 182                 /* can't add callback, do sync now */
 183                 th->th_sync = 1;
 184         } else {
 185                 spin_lock(&exp->exp_lock);
 186                 exp->exp_need_sync = 1;
 187                 spin_unlock(&exp->exp_lock);
 188         }
 189
 190         tti->tti_off = ted->ted_lr_off;
 191         rc = tgt_client_data_write(env, tgt, ted->ted_lcd, &tti->tti_off, th);
 192         EXIT;
 193 out:
 194         dt_trans_stop(env, tgt->lut_bottom, th);
 195         CDEBUG(D_INFO, "%s: update last_rcvd client data for UUID = %s, "
 196                "last_transno = "LPU64": rc = %d\n", tgt->lut_obd->obd_name,
 197                tgt->lut_lsd.lsd_uuid, tgt->lut_lsd.lsd_last_transno, rc);
 198
 199         return rc;
 200 }
 201
 202 int tgt_server_data_read(const struct lu_env *env, struct lu_target *tgt)
 203 {
 204         struct tgt_thread_info  *tti = tgt_th_info(env);
 205         int                      rc;
 206
 207         tti->tti_off = 0;
 208         tti_buf_lsd(tti);
 209         rc = dt_record_read(env, tgt->lut_last_rcvd, &tti->tti_buf,
 210                             &tti->tti_off);
 211         if (rc == 0)
 212                 lsd_le_to_cpu(&tti->tti_lsd, &tgt->lut_lsd);
 213
 214         CDEBUG(D_INFO, "%s: read last_rcvd server data for UUID = %s, "
 215                "last_transno = "LPU64": rc = %d\n", tgt->lut_obd->obd_name,
 216                tgt->lut_lsd.lsd_uuid, tgt->lut_lsd.lsd_last_transno, rc);
 217         return rc;
 218 }
 219 EXPORT_SYMBOL(tgt_server_data_read);
 220
 221 int tgt_server_data_write(const struct lu_env *env, struct lu_target *tgt,
 222                           struct thandle *th)
 223 {
 224         struct tgt_thread_info  *tti = tgt_th_info(env);
 225         int                      rc;
 226
 227         ENTRY;
 228
 229         tti->tti_off = 0;
 230         tti_buf_lsd(tti);
 231         lsd_cpu_to_le(&tgt->lut_lsd, &tti->tti_lsd);
 232
 233         rc = dt_record_write(env, tgt->lut_last_rcvd, &tti->tti_buf,
 234                              &tti->tti_off, th);
 235
 236         CDEBUG(D_INFO, "%s: write last_rcvd server data for UUID = %s, "
 237                "last_transno = "LPU64": rc = %d\n", tgt->lut_obd->obd_name,
 238                tgt->lut_lsd.lsd_uuid, tgt->lut_lsd.lsd_last_transno, rc);
 239
 240         RETURN(rc);
 241 }
 242 EXPORT_SYMBOL(tgt_server_data_write);
 243
 244 /**
 245  * Update server data in last_rcvd
 246  */
 247 int tgt_server_data_update(const struct lu_env *env, struct lu_target *tgt,
 248                            int sync)
 249 {
 250         struct tgt_thread_info  *tti = tgt_th_info(env);
 251         struct thandle          *th;
 252         int                      rc = 0;
 253
 254         ENTRY;
 255
 256         CDEBUG(D_SUPER,
 257                "%s: mount_count is "LPU64", last_transno is "LPU64"\n",
 258                tgt->lut_lsd.lsd_uuid, tgt->lut_obd->u.obt.obt_mount_count,
 259                tgt->lut_last_transno);
 260
 261         /* Always save latest transno to keep it fresh */
 262         spin_lock(&tgt->lut_translock);
 263         tgt->lut_lsd.lsd_last_transno = tgt->lut_last_transno;
 264         spin_unlock(&tgt->lut_translock);
 265
 266         th = dt_trans_create(env, tgt->lut_bottom);
 267         if (IS_ERR(th))
 268                 RETURN(PTR_ERR(th));
 269
 270         th->th_sync = sync;
 271
 272         rc = dt_declare_record_write(env, tgt->lut_last_rcvd,
 273                                      sizeof(struct lr_server_data),
 274                                      tti->tti_off, th);
 275         if (rc)
 276                 GOTO(out, rc);
 277
 278         rc = dt_trans_start(env, tgt->lut_bottom, th);
 279         if (rc)
 280                 GOTO(out, rc);
 281
 282         rc = tgt_server_data_write(env, tgt, th);
 283 out:
 284         dt_trans_stop(env, tgt->lut_bottom, th);
 285
 286         CDEBUG(D_INFO, "%s: update last_rcvd server data for UUID = %s, "
 287                "last_transno = "LPU64": rc = %d\n", tgt->lut_obd->obd_name,
 288                tgt->lut_lsd.lsd_uuid, tgt->lut_lsd.lsd_last_transno, rc);
 289         RETURN(rc);
 290 }
 291 EXPORT_SYMBOL(tgt_server_data_update);
 292
 293 int tgt_truncate_last_rcvd(const struct lu_env *env, struct lu_target *tgt,
 294                            loff_t size)
 295 {
 296         struct dt_object *dt = tgt->lut_last_rcvd;
 297         struct thandle   *th;
 298         struct lu_attr    attr;
 299         int               rc;
 300
 301         ENTRY;
 302
 303         attr.la_size = size;
 304         attr.la_valid = LA_SIZE;
 305
 306         th = dt_trans_create(env, tgt->lut_bottom);
 307         if (IS_ERR(th))
 308                 RETURN(PTR_ERR(th));
 309         rc = dt_declare_punch(env, dt, size, OBD_OBJECT_EOF, th);
 310         if (rc)
 311                 GOTO(cleanup, rc);
 312         rc = dt_declare_attr_set(env, dt, &attr, th);
 313         if (rc)
 314                 GOTO(cleanup, rc);
 315         rc = dt_trans_start_local(env, tgt->lut_bottom, th);
 316         if (rc)
 317                 GOTO(cleanup, rc);
 318
 319         rc = dt_punch(env, dt, size, OBD_OBJECT_EOF, th, BYPASS_CAPA);
 320         if (rc == 0)
 321                 rc = dt_attr_set(env, dt, &attr, th, BYPASS_CAPA);
 322
 323 cleanup:
 324         dt_trans_stop(env, tgt->lut_bottom, th);
 325
 326         RETURN(rc);
 327 }
 328 EXPORT_SYMBOL(tgt_truncate_last_rcvd);
 329
 330 void tgt_client_epoch_update(const struct lu_env *env, struct obd_export *exp)
 331 {
 332         struct lsd_client_data  *lcd = exp->exp_target_data.ted_lcd;
 333         struct lu_target        *tgt = class_exp2tgt(exp);
 334
 335         LASSERT(tgt->lut_bottom);
 336         /** VBR: set client last_epoch to current epoch */
 337         if (lcd->lcd_last_epoch >= tgt->lut_lsd.lsd_start_epoch)
 338                 return;
 339         lcd->lcd_last_epoch = tgt->lut_lsd.lsd_start_epoch;
 340         tgt_client_data_update(env, exp);
 341 }
 342
 343 /**
 344  * Update boot epoch when recovery ends
 345  */
 346 void tgt_boot_epoch_update(struct lu_target *tgt)
 347 {
 348         struct lu_env            env;
 349         struct ptlrpc_request   *req;
 350         __u32                    start_epoch;
 351         cfs_list_t               client_list;
 352         int                      rc;
 353
 354         if (tgt->lut_obd->obd_stopping)
 355                 return;
 356
 357         rc = lu_env_init(&env, LCT_DT_THREAD);
 358         if (rc) {
 359                 CERROR("%s: can't initialize environment: rc = %d\n",
 360                         tgt->lut_obd->obd_name, rc);
 361                 return;
 362         }
 363
 364         spin_lock(&tgt->lut_translock);
 365         start_epoch = lr_epoch(tgt->lut_last_transno) + 1;
 366         tgt->lut_last_transno = (__u64)start_epoch << LR_EPOCH_BITS;
 367         tgt->lut_lsd.lsd_start_epoch = start_epoch;
 368         spin_unlock(&tgt->lut_translock);
 369
 370         CFS_INIT_LIST_HEAD(&client_list);
 371         /**
 372          * The recovery is not yet finished and final queue can still be updated
 373          * with resend requests. Move final list to separate one for processing
 374          */
 375         spin_lock(&tgt->lut_obd->obd_recovery_task_lock);
 376         cfs_list_splice_init(&tgt->lut_obd->obd_final_req_queue, &client_list);
 377         spin_unlock(&tgt->lut_obd->obd_recovery_task_lock);
 378
 379         /**
 380          * go through list of exports participated in recovery and
 381          * set new epoch for them
 382          */
 383         cfs_list_for_each_entry(req, &client_list, rq_list) {
 384                 LASSERT(!req->rq_export->exp_delayed);
 385                 if (!req->rq_export->exp_vbr_failed)
 386                         tgt_client_epoch_update(&env, req->rq_export);
 387         }
 388         /** return list back at once */
 389         spin_lock(&tgt->lut_obd->obd_recovery_task_lock);
 390         cfs_list_splice_init(&client_list, &tgt->lut_obd->obd_final_req_queue);
 391         spin_unlock(&tgt->lut_obd->obd_recovery_task_lock);
 392         /** update server epoch */
 393         tgt_server_data_update(&env, tgt, 1);
 394         lu_env_fini(&env);
 395 }
 396 EXPORT_SYMBOL(tgt_boot_epoch_update);
 397
 398 /**
 399  * commit callback, need to update last_commited value
 400  */
 401 struct tgt_last_committed_callback {
 402         struct dt_txn_commit_cb  llcc_cb;
 403         struct lu_target        *llcc_tgt;
 404         struct obd_export       *llcc_exp;
 405         __u64                    llcc_transno;
 406 };
 407
 408 void tgt_cb_last_committed(struct lu_env *env, struct thandle *th,
 409                            struct dt_txn_commit_cb *cb, int err)
 410 {
 411         struct tgt_last_committed_callback *ccb;
 412
 413         ccb = container_of0(cb, struct tgt_last_committed_callback, llcc_cb);
 414
 415         LASSERT(ccb->llcc_tgt != NULL);
 416         LASSERT(ccb->llcc_exp->exp_obd == ccb->llcc_tgt->lut_obd);
 417
 418         spin_lock(&ccb->llcc_tgt->lut_translock);
 419         if (ccb->llcc_transno > ccb->llcc_tgt->lut_obd->obd_last_committed)
 420                 ccb->llcc_tgt->lut_obd->obd_last_committed = ccb->llcc_transno;
 421
 422         LASSERT(ccb->llcc_exp);
 423         if (ccb->llcc_transno > ccb->llcc_exp->exp_last_committed) {
 424                 ccb->llcc_exp->exp_last_committed = ccb->llcc_transno;
 425                 spin_unlock(&ccb->llcc_tgt->lut_translock);
 426                 ptlrpc_commit_replies(ccb->llcc_exp);
 427         } else {
 428                 spin_unlock(&ccb->llcc_tgt->lut_translock);
 429         }
 430         class_export_cb_put(ccb->llcc_exp);
 431         if (ccb->llcc_transno)
 432                 CDEBUG(D_HA, "%s: transno "LPD64" is committed\n",
 433                        ccb->llcc_tgt->lut_obd->obd_name, ccb->llcc_transno);
 434         OBD_FREE_PTR(ccb);
 435 }
 436
 437 int tgt_last_commit_cb_add(struct thandle *th, struct lu_target *tgt,
 438                            struct obd_export *exp, __u64 transno)
 439 {
 440         struct tgt_last_committed_callback      *ccb;
 441         struct dt_txn_commit_cb                 *dcb;
 442         int                                      rc;
 443
 444         OBD_ALLOC_PTR(ccb);
 445         if (ccb == NULL)
 446                 return -ENOMEM;
 447
 448         ccb->llcc_tgt = tgt;
 449         ccb->llcc_exp = class_export_cb_get(exp);
 450         ccb->llcc_transno = transno;
 451
 452         dcb = &ccb->llcc_cb;
 453         dcb->dcb_func = tgt_cb_last_committed;
 454         CFS_INIT_LIST_HEAD(&dcb->dcb_linkage);
 455         strncpy(dcb->dcb_name, "tgt_cb_last_committed", MAX_COMMIT_CB_STR_LEN);
 456         dcb->dcb_name[MAX_COMMIT_CB_STR_LEN - 1] = '\0';
 457
 458         rc = dt_trans_cb_add(th, dcb);
 459         if (rc) {
 460                 class_export_cb_put(exp);
 461                 OBD_FREE_PTR(ccb);
 462         }
 463
 464         if (exp_connect_flags(exp) & OBD_CONNECT_LIGHTWEIGHT)
 465                 /* report failure to force synchronous operation */
 466                 return -EPERM;
 467
 468         return rc;
 469 }
 470 EXPORT_SYMBOL(tgt_last_commit_cb_add);
 471
 472 struct tgt_new_client_callback {
 473         struct dt_txn_commit_cb  lncc_cb;
 474         struct obd_export       *lncc_exp;
 475 };
 476
 477 void tgt_cb_new_client(struct lu_env *env, struct thandle *th,
 478                        struct dt_txn_commit_cb *cb, int err)
 479 {
 480         struct tgt_new_client_callback *ccb;
 481
 482         ccb = container_of0(cb, struct tgt_new_client_callback, lncc_cb);
 483
 484         LASSERT(ccb->lncc_exp->exp_obd);
 485
 486         CDEBUG(D_RPCTRACE, "%s: committing for initial connect of %s\n",
 487                ccb->lncc_exp->exp_obd->obd_name,
 488                ccb->lncc_exp->exp_client_uuid.uuid);
 489
 490         spin_lock(&ccb->lncc_exp->exp_lock);
 491         ccb->lncc_exp->exp_need_sync = 0;
 492         spin_unlock(&ccb->lncc_exp->exp_lock);
 493         class_export_cb_put(ccb->lncc_exp);
 494
 495         OBD_FREE_PTR(ccb);
 496 }
 497
 498 int tgt_new_client_cb_add(struct thandle *th, struct obd_export *exp)
 499 {
 500         struct tgt_new_client_callback  *ccb;
 501         struct dt_txn_commit_cb         *dcb;
 502         int                              rc;
 503
 504         OBD_ALLOC_PTR(ccb);
 505         if (ccb == NULL)
 506                 return -ENOMEM;
 507
 508         ccb->lncc_exp = class_export_cb_get(exp);
 509
 510         dcb = &ccb->lncc_cb;
 511         dcb->dcb_func = tgt_cb_new_client;
 512         CFS_INIT_LIST_HEAD(&dcb->dcb_linkage);
 513         strncpy(dcb->dcb_name, "tgt_cb_new_client", MAX_COMMIT_CB_STR_LEN);
 514         dcb->dcb_name[MAX_COMMIT_CB_STR_LEN - 1] = '\0';
 515
 516         rc = dt_trans_cb_add(th, dcb);
 517         if (rc) {
 518                 class_export_cb_put(exp);
 519                 OBD_FREE_PTR(ccb);
 520         }
 521         return rc;
 522 }
 523
 524 /**
 525  * Add new client to the last_rcvd upon new connection.
 526  *
 527  * We use a bitmap to locate a free space in the last_rcvd file and initialize
 528  * tg_export_data.
 529  */
 530 int tgt_client_new(const struct lu_env *env, struct obd_export *exp)
 531 {
 532         struct tg_export_data   *ted = &exp->exp_target_data;
 533         struct lu_target        *tgt = class_exp2tgt(exp);
 534         int                      rc = 0, idx;
 535
 536         ENTRY;
 537
 538         LASSERT(tgt->lut_client_bitmap != NULL);
 539         if (!strcmp(ted->ted_lcd->lcd_uuid, tgt->lut_obd->obd_uuid.uuid))
 540                 RETURN(0);
 541
 542         mutex_init(&ted->ted_lcd_lock);
 543
 544         if (exp_connect_flags(exp) & OBD_CONNECT_LIGHTWEIGHT)
 545                 RETURN(0);
 546
 547         /* the bitmap operations can handle cl_idx > sizeof(long) * 8, so
 548          * there's no need for extra complication here
 549          */
 550         idx = find_first_zero_bit(tgt->lut_client_bitmap, LR_MAX_CLIENTS);
 551 repeat:
 552         if (idx >= LR_MAX_CLIENTS ||
 553             OBD_FAIL_CHECK(OBD_FAIL_MDS_CLIENT_ADD)) {
 554                 CERROR("%s: no room for %u clients - fix LR_MAX_CLIENTS\n",
 555                        tgt->lut_obd->obd_name,  idx);
 556                 RETURN(-EOVERFLOW);
 557         }
 558         if (test_and_set_bit(idx, tgt->lut_client_bitmap)) {
 559                 idx = find_next_zero_bit(tgt->lut_client_bitmap,
 560                                              LR_MAX_CLIENTS, idx);
 561                 goto repeat;
 562         }
 563
 564         CDEBUG(D_INFO, "%s: client at idx %d with UUID '%s' added\n",
 565                tgt->lut_obd->obd_name, idx, ted->ted_lcd->lcd_uuid);
 566
 567         ted->ted_lr_idx = idx;
 568         ted->ted_lr_off = tgt->lut_lsd.lsd_client_start +
 569                           idx * tgt->lut_lsd.lsd_client_size;
 570
 571         LASSERTF(ted->ted_lr_off > 0, "ted_lr_off = %llu\n", ted->ted_lr_off);
 572
 573         CDEBUG(D_INFO, "%s: new client at index %d (%llu) with UUID '%s'\n",
 574                tgt->lut_obd->obd_name, ted->ted_lr_idx, ted->ted_lr_off,
 575                ted->ted_lcd->lcd_uuid);
 576
 577         if (OBD_FAIL_CHECK(OBD_FAIL_TGT_CLIENT_ADD))
 578                 RETURN(-ENOSPC);
 579
 580         rc = tgt_client_data_update(env, exp);
 581         if (rc)
 582                 CERROR("%s: Failed to write client lcd at idx %d, rc %d\n",
 583                        tgt->lut_obd->obd_name, idx, rc);
 584
 585         RETURN(rc);
 586 }
 587 EXPORT_SYMBOL(tgt_client_new);
 588
 589 /* Add client data to the MDS.  We use a bitmap to locate a free space
 590  * in the last_rcvd file if cl_off is -1 (i.e. a new client).
 591  * Otherwise, we just have to read the data from the last_rcvd file and
 592  * we know its offset.
 593  *
 594  * It should not be possible to fail adding an existing client - otherwise
 595  * mdt_init_server_data() callsite needs to be fixed.
 596  */
 597 int tgt_client_add(const struct lu_env *env,  struct obd_export *exp, int idx)
 598 {
 599         struct tg_export_data   *ted = &exp->exp_target_data;
 600         struct lu_target        *tgt = class_exp2tgt(exp);
 601
 602         ENTRY;
 603
 604         LASSERT(tgt->lut_client_bitmap != NULL);
 605         LASSERTF(idx >= 0, "%d\n", idx);
 606
 607         if (!strcmp(ted->ted_lcd->lcd_uuid, tgt->lut_obd->obd_uuid.uuid) ||
 608             exp_connect_flags(exp) & OBD_CONNECT_LIGHTWEIGHT)
 609                 RETURN(0);
 610
 611         if (test_and_set_bit(idx, tgt->lut_client_bitmap)) {
 612                 CERROR("%s: client %d: bit already set in bitmap!!\n",
 613                        tgt->lut_obd->obd_name,  idx);
 614                 LBUG();
 615         }
 616
 617         CDEBUG(D_INFO, "%s: client at idx %d with UUID '%s' added\n",
 618                tgt->lut_obd->obd_name, idx, ted->ted_lcd->lcd_uuid);
 619
 620         ted->ted_lr_idx = idx;
 621         ted->ted_lr_off = tgt->lut_lsd.lsd_client_start +
 622                           idx * tgt->lut_lsd.lsd_client_size;
 623
 624         mutex_init(&ted->ted_lcd_lock);
 625
 626         LASSERTF(ted->ted_lr_off > 0, "ted_lr_off = %llu\n", ted->ted_lr_off);
 627
 628         RETURN(0);
 629 }
 630 EXPORT_SYMBOL(tgt_client_add);
 631
 632 int tgt_client_del(const struct lu_env *env, struct obd_export *exp)
 633 {
 634         struct tg_export_data   *ted = &exp->exp_target_data;
 635         struct lu_target        *tgt = class_exp2tgt(exp);
 636         int                      rc;
 637
 638         ENTRY;
 639
 640         LASSERT(ted->ted_lcd);
 641
 642         /* XXX if lcd_uuid were a real obd_uuid, I could use obd_uuid_equals */
 643         if (!strcmp((char *)ted->ted_lcd->lcd_uuid,
 644                     (char *)tgt->lut_obd->obd_uuid.uuid) ||
 645             exp_connect_flags(exp) & OBD_CONNECT_LIGHTWEIGHT)
 646                 RETURN(0);
 647
 648         CDEBUG(D_INFO, "%s: del client at idx %u, off %lld, UUID '%s'\n",
 649                tgt->lut_obd->obd_name, ted->ted_lr_idx, ted->ted_lr_off,
 650                ted->ted_lcd->lcd_uuid);
 651
 652         /* Clear the bit _after_ zeroing out the client so we don't
 653            race with filter_client_add and zero out new clients.*/
 654         if (!test_bit(ted->ted_lr_idx, tgt->lut_client_bitmap)) {
 655                 CERROR("%s: client %u: bit already clear in bitmap!!\n",
 656                        tgt->lut_obd->obd_name, ted->ted_lr_idx);
 657                 LBUG();
 658         }
 659
 660         /* Do not erase record for recoverable client. */
 661         if (exp->exp_flags & OBD_OPT_FAILOVER)
 662                 RETURN(0);
 663
 664         /* Make sure the server's last_transno is up to date.
 665          * This should be done before zeroing client slot so last_transno will
 666          * be in server data or in client data in case of failure */
 667         rc = tgt_server_data_update(env, tgt, 0);
 668         if (rc != 0) {
 669                 CERROR("%s: failed to update server data, skip client %s "
 670                        "zeroing, rc %d\n", tgt->lut_obd->obd_name,
 671                        ted->ted_lcd->lcd_uuid, rc);
 672                 RETURN(rc);
 673         }
 674
 675         mutex_lock(&ted->ted_lcd_lock);
 676         memset(ted->ted_lcd->lcd_uuid, 0, sizeof ted->ted_lcd->lcd_uuid);
 677         rc = tgt_client_data_update(env, exp);
 678         mutex_unlock(&ted->ted_lcd_lock);
 679
 680         CDEBUG(rc == 0 ? D_INFO : D_ERROR,
 681                "%s: zeroing out client %s at idx %u (%llu), rc %d\n",
 682                tgt->lut_obd->obd_name, ted->ted_lcd->lcd_uuid,
 683                ted->ted_lr_idx, ted->ted_lr_off, rc);
 684         RETURN(rc);
 685 }
 686 EXPORT_SYMBOL(tgt_client_del);
 687
 688 /*
 689  * last_rcvd & last_committed update callbacks
 690  */
 691 int tgt_last_rcvd_update(const struct lu_env *env, struct lu_target *tgt,
 692                          struct dt_object *obj, __u64 opdata,
 693                          struct thandle *th, struct ptlrpc_request *req)
 694 {
 695         struct tgt_thread_info  *tti = tgt_th_info(env);
 696         struct tgt_session_info *tsi = tgt_ses_info(env);
 697         struct tg_export_data   *ted;
 698         __u64                   *transno_p;
 699         int                      rc = 0;
 700         bool                     lw_client, update = false;
 701
 702         ENTRY;
 703
 704         if (tsi->tsi_has_trans) {
 705                 /* XXX: currently there are allowed cases, but the wrong cases
 706                  * are also possible, so better check is needed here */
 707                 CDEBUG(D_INFO, "More than one transaction "LPU64"\n",
 708                        tti->tti_transno);
 709                 return 0;
 710         }
 711
 712         tsi->tsi_has_trans = 1;
 713         /* that can be OUT target and we need tgt_session_info */
 714         if (req == NULL) {
 715                 req = tgt_ses_req(tsi);
 716                 if (req == NULL) /* echo client case */
 717                         RETURN(0);
 718         }
 719
 720         ted = &req->rq_export->exp_target_data;
 721
 722         lw_client = exp_connect_flags(req->rq_export) & OBD_CONNECT_LIGHTWEIGHT;
 723         if (ted->ted_lr_idx < 0 && !lw_client)
 724                 /* ofd connect may cause transaction before export has
 725                  * last_rcvd slot */
 726                 RETURN(0);
 727
 728         tti->tti_transno = lustre_msg_get_transno(req->rq_reqmsg);
 729
 730         spin_lock(&tgt->lut_translock);
 731         if (th->th_result != 0) {
 732                 if (tti->tti_transno != 0) {
 733                         CERROR("%s: replay transno "LPU64" failed: rc = %d\n",
 734                                tgt_name(tgt), tti->tti_transno, th->th_result);
 735                 }
 736         } else if (tti->tti_transno == 0) {
 737                 tti->tti_transno = ++tgt->lut_last_transno;
 738         } else {
 739                 /* should be replay */
 740                 if (tti->tti_transno > tgt->lut_last_transno)
 741                         tgt->lut_last_transno = tti->tti_transno;
 742         }
 743         spin_unlock(&tgt->lut_translock);
 744
 745         /** VBR: set new versions */
 746         if (th->th_result == 0 && obj != NULL)
 747                 dt_version_set(env, obj, tti->tti_transno, th);
 748
 749         /* filling reply data */
 750         CDEBUG(D_INODE, "transno = "LPU64", last_committed = "LPU64"\n",
 751                tti->tti_transno, tgt->lut_obd->obd_last_committed);
 752
 753         req->rq_transno = tti->tti_transno;
 754         lustre_msg_set_transno(req->rq_repmsg, tti->tti_transno);
 755
 756         /* if can't add callback, do sync write */
 757         th->th_sync |= !!tgt_last_commit_cb_add(th, tgt, req->rq_export,
 758                                                 tti->tti_transno);
 759
 760         if (lw_client) {
 761                 /* All operations performed by LW clients are synchronous and
 762                  * we store the committed transno in the last_rcvd header */
 763                 spin_lock(&tgt->lut_translock);
 764                 if (tti->tti_transno > tgt->lut_lsd.lsd_last_transno) {
 765                         tgt->lut_lsd.lsd_last_transno = tti->tti_transno;
 766                         update = true;
 767                 }
 768                 spin_unlock(&tgt->lut_translock);
 769                 /* Although lightweight (LW) connections have no slot in
 770                  * last_rcvd, we still want to maintain the in-memory
 771                  * lsd_client_data structure in order to properly handle reply
 772                  * reconstruction. */
 773         } else if (ted->ted_lr_off == 0) {
 774                 CERROR("%s: client idx %d has offset %lld\n",
 775                        tgt_name(tgt), ted->ted_lr_idx, ted->ted_lr_off);
 776                 RETURN(-EINVAL);
 777         }
 778
 779         /* if the export has already been disconnected, we have no last_rcvd
 780          * slot, update server data with latest transno then */
 781         if (ted->ted_lcd == NULL) {
 782                 CWARN("commit transaction for disconnected client %s: rc %d\n",
 783                       req->rq_export->exp_client_uuid.uuid, rc);
 784                 GOTO(srv_update, rc = 0);
 785         }
 786
 787         mutex_lock(&ted->ted_lcd_lock);
 788         LASSERT(ergo(tti->tti_transno == 0, th->th_result != 0));
 789         if (lustre_msg_get_opc(req->rq_reqmsg) == MDS_CLOSE ||
 790             lustre_msg_get_opc(req->rq_reqmsg) == MDS_DONE_WRITING) {
 791                 transno_p = &ted->ted_lcd->lcd_last_close_transno;
 792                 ted->ted_lcd->lcd_last_close_xid = req->rq_xid;
 793                 ted->ted_lcd->lcd_last_close_result = th->th_result;
 794         } else {
 795                 /* VBR: save versions in last_rcvd for reconstruct. */
 796                 __u64 *pre_versions = lustre_msg_get_versions(req->rq_repmsg);
 797
 798                 if (pre_versions) {
 799                         ted->ted_lcd->lcd_pre_versions[0] = pre_versions[0];
 800                         ted->ted_lcd->lcd_pre_versions[1] = pre_versions[1];
 801                         ted->ted_lcd->lcd_pre_versions[2] = pre_versions[2];
 802                         ted->ted_lcd->lcd_pre_versions[3] = pre_versions[3];
 803                 }
 804                 transno_p = &ted->ted_lcd->lcd_last_transno;
 805                 ted->ted_lcd->lcd_last_xid = req->rq_xid;
 806                 ted->ted_lcd->lcd_last_result = th->th_result;
 807                 /* XXX: lcd_last_data is __u32 but intent_dispostion is __u64,
 808                  * see struct ldlm_reply->lock_policy_res1; */
 809                 ted->ted_lcd->lcd_last_data = opdata;
 810         }
 811
 812         /* Update transno in slot only if non-zero number, i.e. no errors */
 813         if (likely(tti->tti_transno != 0)) {
 814                 if (*transno_p > tti->tti_transno) {
 815                         CERROR("%s: trying to overwrite bigger transno:"
 816                                "on-disk: "LPU64", new: "LPU64" replay: %d. "
 817                                "see LU-617.\n", tgt_name(tgt), *transno_p,
 818                                tti->tti_transno, req_is_replay(req));
 819                         if (req_is_replay(req)) {
 820                                 spin_lock(&req->rq_export->exp_lock);
 821                                 req->rq_export->exp_vbr_failed = 1;
 822                                 spin_unlock(&req->rq_export->exp_lock);
 823                         }
 824                         mutex_unlock(&ted->ted_lcd_lock);
 825                         RETURN(req_is_replay(req) ? -EOVERFLOW : 0);
 826                 }
 827                 *transno_p = tti->tti_transno;
 828         }
 829
 830         if (!lw_client) {
 831                 tti->tti_off = ted->ted_lr_off;
 832                 rc = tgt_client_data_write(env, tgt, ted->ted_lcd, &tti->tti_off, th);
 833                 if (rc < 0) {
 834                         mutex_unlock(&ted->ted_lcd_lock);
 835                         RETURN(rc);
 836                 }
 837         }
 838         mutex_unlock(&ted->ted_lcd_lock);
 839         EXIT;
 840 srv_update:
 841         if (update)
 842                 rc = tgt_server_data_write(env, tgt, th);
 843         return rc;
 844 }
 845 EXPORT_SYMBOL(tgt_last_rcvd_update);
 846
 847 /*
 848  * last_rcvd update for echo client simulation.
 849  * It updates last_rcvd client slot and version of object in
 850  * simple way but with all locks to simulate all drawbacks
 851  */
 852 int tgt_last_rcvd_update_echo(const struct lu_env *env, struct lu_target *tgt,
 853                               struct dt_object *obj, struct thandle *th,
 854                               struct obd_export *exp)
 855 {
 856         struct tgt_thread_info  *tti = tgt_th_info(env);
 857         struct tg_export_data   *ted = &exp->exp_target_data;
 858         int                      rc = 0;
 859
 860         ENTRY;
 861
 862         tti->tti_transno = 0;
 863
 864         spin_lock(&tgt->lut_translock);
 865         if (th->th_result == 0)
 866                 tti->tti_transno = ++tgt->lut_last_transno;
 867         spin_unlock(&tgt->lut_translock);
 868
 869         /** VBR: set new versions */
 870         if (th->th_result == 0 && obj != NULL)
 871                 dt_version_set(env, obj, tti->tti_transno, th);
 872
 873         /* if can't add callback, do sync write */
 874         th->th_sync |= !!tgt_last_commit_cb_add(th, tgt, exp,
 875                                                 tti->tti_transno);
 876
 877         LASSERT(ted->ted_lr_off > 0);
 878
 879         mutex_lock(&ted->ted_lcd_lock);
 880         LASSERT(ergo(tti->tti_transno == 0, th->th_result != 0));
 881         ted->ted_lcd->lcd_last_transno = tti->tti_transno;
 882         ted->ted_lcd->lcd_last_result = th->th_result;
 883
 884         tti->tti_off = ted->ted_lr_off;
 885         rc = tgt_client_data_write(env, tgt, ted->ted_lcd, &tti->tti_off, th);
 886         mutex_unlock(&ted->ted_lcd_lock);
 887         RETURN(rc);
 888 }
 889 EXPORT_SYMBOL(tgt_last_rcvd_update_echo);