lustre/obdclass/llog.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) 2003, 2010, Oracle and/or its affiliates. All rights reserved.
  24  * Use is subject to license terms.
  25  *
  26  * Copyright (c) 2012, 2016, Intel Corporation.
  27  */
  28 /*
  29  * This file is part of Lustre, http://www.lustre.org/
  30  * Lustre is a trademark of Sun Microsystems, Inc.
  31  *
  32  * lustre/obdclass/llog.c
  33  *
  34  * OST<->MDS recovery logging infrastructure.
  35  * Invariants in implementation:
  36  * - we do not share logs among different OST<->MDS connections, so that
  37  *   if an OST or MDS fails it need only look at log(s) relevant to itself
  38  *
  39  * Author: Andreas Dilger <adilger@clusterfs.com>
  40  * Author: Alex Zhuravlev <bzzz@whamcloud.com>
  41  * Author: Mikhail Pershin <tappro@whamcloud.com>
  42  */
  43
  44 #define DEBUG_SUBSYSTEM S_LOG
  45
  46 #include <linux/pid_namespace.h>
  47 #include <linux/kthread.h>
  48 #include <llog_swab.h>
  49 #include <lustre_log.h>
  50 #include <obd_class.h>
  51 #include "llog_internal.h"
  52 /*
  53  * Allocate a new log or catalog handle
  54  * Used inside llog_open().
  55  */
  56 static struct llog_handle *llog_alloc_handle(void)
  57 {
  58         struct llog_handle *loghandle;
  59
  60         OBD_ALLOC_PTR(loghandle);
  61         if (loghandle == NULL)
  62                 return NULL;
  63
  64         init_rwsem(&loghandle->lgh_lock);
  65         mutex_init(&loghandle->lgh_hdr_mutex);
  66         INIT_LIST_HEAD(&loghandle->u.phd.phd_entry);
  67         atomic_set(&loghandle->lgh_refcount, 1);
  68
  69         return loghandle;
  70 }
  71
  72 /*
  73  * Free llog handle and header data if exists. Used in llog_close() only
  74  */
  75 static void llog_free_handle(struct llog_handle *loghandle)
  76 {
  77         LASSERT(loghandle != NULL);
  78
  79         /* failed llog_init_handle */
  80         if (loghandle->lgh_hdr == NULL)
  81                 goto out;
  82
  83         if (loghandle->lgh_hdr->llh_flags & LLOG_F_IS_PLAIN)
  84                 LASSERT(list_empty(&loghandle->u.phd.phd_entry));
  85         else if (loghandle->lgh_hdr->llh_flags & LLOG_F_IS_CAT)
  86                 LASSERT(list_empty(&loghandle->u.chd.chd_head));
  87         OBD_FREE_LARGE(loghandle->lgh_hdr, loghandle->lgh_hdr_size);
  88 out:
  89         OBD_FREE_PTR(loghandle);
  90 }
  91
  92 void llog_handle_get(struct llog_handle *loghandle)
  93 {
  94         atomic_inc(&loghandle->lgh_refcount);
  95 }
  96
  97 void llog_handle_put(struct llog_handle *loghandle)
  98 {
  99         LASSERT(atomic_read(&loghandle->lgh_refcount) > 0);
 100         if (atomic_dec_and_test(&loghandle->lgh_refcount))
 101                 llog_free_handle(loghandle);
 102 }
 103
 104 static int llog_declare_destroy(const struct lu_env *env,
 105                                 struct llog_handle *handle,
 106                                 struct thandle *th)
 107 {
 108         struct llog_operations *lop;
 109         int rc;
 110
 111         ENTRY;
 112
 113         rc = llog_handle2ops(handle, &lop);
 114         if (rc)
 115                 RETURN(rc);
 116         if (lop->lop_declare_destroy == NULL)
 117                 RETURN(-EOPNOTSUPP);
 118
 119         rc = lop->lop_declare_destroy(env, handle, th);
 120
 121         RETURN(rc);
 122 }
 123
 124 int llog_trans_destroy(const struct lu_env *env, struct llog_handle *handle,
 125                        struct thandle *th)
 126 {
 127         struct llog_operations  *lop;
 128         int rc;
 129         ENTRY;
 130
 131         rc = llog_handle2ops(handle, &lop);
 132         if (rc < 0)
 133                 RETURN(rc);
 134         if (lop->lop_destroy == NULL)
 135                 RETURN(-EOPNOTSUPP);
 136
 137         LASSERT(handle->lgh_obj != NULL);
 138         if (!dt_object_exists(handle->lgh_obj))
 139                 RETURN(0);
 140
 141         rc = lop->lop_destroy(env, handle, th);
 142
 143         RETURN(rc);
 144 }
 145
 146 int llog_destroy(const struct lu_env *env, struct llog_handle *handle)
 147 {
 148         struct llog_operations  *lop;
 149         struct dt_device        *dt;
 150         struct thandle          *th;
 151         int rc;
 152
 153         ENTRY;
 154
 155         rc = llog_handle2ops(handle, &lop);
 156         if (rc < 0)
 157                 RETURN(rc);
 158         if (lop->lop_destroy == NULL)
 159                 RETURN(-EOPNOTSUPP);
 160
 161         if (handle->lgh_obj == NULL) {
 162                 /* if lgh_obj == NULL, then it is from client side destroy */
 163                 rc = lop->lop_destroy(env, handle, NULL);
 164                 RETURN(rc);
 165         }
 166
 167         if (!dt_object_exists(handle->lgh_obj))
 168                 RETURN(0);
 169
 170         dt = lu2dt_dev(handle->lgh_obj->do_lu.lo_dev);
 171
 172         th = dt_trans_create(env, dt);
 173         if (IS_ERR(th))
 174                 RETURN(PTR_ERR(th));
 175
 176         rc = llog_declare_destroy(env, handle, th);
 177         if (rc != 0)
 178                 GOTO(out_trans, rc);
 179
 180         rc = dt_trans_start_local(env, dt, th);
 181         if (rc < 0)
 182                 GOTO(out_trans, rc);
 183
 184         rc = lop->lop_destroy(env, handle, th);
 185
 186 out_trans:
 187         dt_trans_stop(env, dt, th);
 188
 189         RETURN(rc);
 190 }
 191 EXPORT_SYMBOL(llog_destroy);
 192
 193 /* returns negative on error; 0 if success; 1 if success & log destroyed */
 194 int llog_cancel_rec(const struct lu_env *env, struct llog_handle *loghandle,
 195                     int index)
 196 {
 197         struct llog_thread_info *lgi = llog_info(env);
 198         struct dt_device        *dt;
 199         struct llog_log_hdr     *llh = loghandle->lgh_hdr;
 200         struct thandle          *th;
 201         int                      rc;
 202         int rc1;
 203         bool subtract_count = false;
 204
 205         ENTRY;
 206
 207         CDEBUG(D_RPCTRACE, "Canceling %d in log "DFID"\n", index,
 208                PFID(&loghandle->lgh_id.lgl_oi.oi_fid));
 209
 210         if (index == 0) {
 211                 CERROR("Can't cancel index 0 which is header\n");
 212                 RETURN(-EINVAL);
 213         }
 214
 215         LASSERT(loghandle != NULL);
 216         LASSERT(loghandle->lgh_ctxt != NULL);
 217         LASSERT(loghandle->lgh_obj != NULL);
 218
 219         dt = lu2dt_dev(loghandle->lgh_obj->do_lu.lo_dev);
 220
 221         th = dt_trans_create(env, dt);
 222         if (IS_ERR(th))
 223                 RETURN(PTR_ERR(th));
 224
 225         rc = llog_declare_write_rec(env, loghandle, &llh->llh_hdr, index, th);
 226         if (rc < 0)
 227                 GOTO(out_trans, rc);
 228
 229         if ((llh->llh_flags & LLOG_F_ZAP_WHEN_EMPTY)) {
 230                 rc = llog_declare_destroy(env, loghandle, th);
 231                 if (rc < 0)
 232                         GOTO(out_trans, rc);
 233         }
 234
 235         th->th_wait_submit = 1;
 236         rc = dt_trans_start_local(env, dt, th);
 237         if (rc < 0)
 238                 GOTO(out_trans, rc);
 239
 240         down_write(&loghandle->lgh_lock);
 241         /* clear bitmap */
 242         mutex_lock(&loghandle->lgh_hdr_mutex);
 243         if (!ext2_clear_bit(index, LLOG_HDR_BITMAP(llh))) {
 244                 CDEBUG(D_RPCTRACE, "Catalog index %u already clear?\n", index);
 245                 GOTO(out_unlock, rc);
 246         }
 247
 248         loghandle->lgh_hdr->llh_count--;
 249         subtract_count = true;
 250         /* Pass this index to llog_osd_write_rec(), which will use the index
 251          * to only update the necesary bitmap. */
 252         lgi->lgi_cookie.lgc_index = index;
 253         /* update header */
 254         rc = llog_write_rec(env, loghandle, &llh->llh_hdr, &lgi->lgi_cookie,
 255                             LLOG_HEADER_IDX, th);
 256         if (rc != 0)
 257                 GOTO(out_unlock, rc);
 258
 259         if ((llh->llh_flags & LLOG_F_ZAP_WHEN_EMPTY) &&
 260             (llh->llh_count == 1) &&
 261             ((loghandle->lgh_last_idx == LLOG_HDR_BITMAP_SIZE(llh) - 1) ||
 262              (loghandle->u.phd.phd_cat_handle != NULL &&
 263               loghandle->u.phd.phd_cat_handle->u.chd.chd_current_log !=
 264                 loghandle))) {
 265                 /* never try to destroy it again */
 266                 llh->llh_flags &= ~LLOG_F_ZAP_WHEN_EMPTY;
 267                 rc = llog_trans_destroy(env, loghandle, th);
 268                 if (rc < 0) {
 269                         /* Sigh, can not destroy the final plain llog, but
 270                          * the bitmap has been clearly, so the record can not
 271                          * be accessed anymore, let's return 0 for now, and
 272                          * the orphan will be handled by LFSCK. */
 273                         CERROR("%s: can't destroy empty llog "DFID": rc = %d\n",
 274                                loghandle->lgh_ctxt->loc_obd->obd_name,
 275                                PFID(&loghandle->lgh_id.lgl_oi.oi_fid), rc);
 276                         GOTO(out_unlock, rc = 0);
 277                 }
 278                 rc = LLOG_DEL_PLAIN;
 279         }
 280
 281 out_unlock:
 282         mutex_unlock(&loghandle->lgh_hdr_mutex);
 283         up_write(&loghandle->lgh_lock);
 284 out_trans:
 285         rc1 = dt_trans_stop(env, dt, th);
 286         if (rc == 0)
 287                 rc = rc1;
 288         if (rc < 0 && subtract_count) {
 289                 mutex_lock(&loghandle->lgh_hdr_mutex);
 290                 loghandle->lgh_hdr->llh_count++;
 291                 ext2_set_bit(index, LLOG_HDR_BITMAP(llh));
 292                 mutex_unlock(&loghandle->lgh_hdr_mutex);
 293         }
 294         RETURN(rc);
 295 }
 296
 297 int llog_read_header(const struct lu_env *env, struct llog_handle *handle,
 298                      const struct obd_uuid *uuid)
 299 {
 300         struct llog_operations *lop;
 301         int rc;
 302         ENTRY;
 303
 304         rc = llog_handle2ops(handle, &lop);
 305         if (rc)
 306                 RETURN(rc);
 307
 308         if (lop->lop_read_header == NULL)
 309                 RETURN(-EOPNOTSUPP);
 310
 311         rc = lop->lop_read_header(env, handle);
 312         if (rc == LLOG_EEMPTY) {
 313                 struct llog_log_hdr *llh = handle->lgh_hdr;
 314
 315                 /* lrh_len should be initialized in llog_init_handle */
 316                 handle->lgh_last_idx = 0; /* header is record with index 0 */
 317                 llh->llh_count = 1;         /* for the header record */
 318                 llh->llh_hdr.lrh_type = LLOG_HDR_MAGIC;
 319                 LASSERT(handle->lgh_ctxt->loc_chunk_size >=
 320                                                 LLOG_MIN_CHUNK_SIZE);
 321                 llh->llh_hdr.lrh_len = handle->lgh_ctxt->loc_chunk_size;
 322                 llh->llh_hdr.lrh_index = 0;
 323                 llh->llh_timestamp = ktime_get_real_seconds();
 324                 if (uuid)
 325                         memcpy(&llh->llh_tgtuuid, uuid,
 326                                sizeof(llh->llh_tgtuuid));
 327                 llh->llh_bitmap_offset = offsetof(typeof(*llh), llh_bitmap);
 328                 /* Since update llog header might also call this function,
 329                  * let's reset the bitmap to 0 here */
 330                 memset(LLOG_HDR_BITMAP(llh), 0, llh->llh_hdr.lrh_len -
 331                                                 llh->llh_bitmap_offset -
 332                                                 sizeof(llh->llh_tail));
 333                 ext2_set_bit(0, LLOG_HDR_BITMAP(llh));
 334                 LLOG_HDR_TAIL(llh)->lrt_len = llh->llh_hdr.lrh_len;
 335                 LLOG_HDR_TAIL(llh)->lrt_index = llh->llh_hdr.lrh_index;
 336                 rc = 0;
 337         }
 338         RETURN(rc);
 339 }
 340 EXPORT_SYMBOL(llog_read_header);
 341
 342 int llog_init_handle(const struct lu_env *env, struct llog_handle *handle,
 343                      int flags, struct obd_uuid *uuid)
 344 {
 345         struct llog_log_hdr     *llh;
 346         enum llog_flag           fmt = flags & LLOG_F_EXT_MASK;
 347         int                      rc;
 348         int                     chunk_size = handle->lgh_ctxt->loc_chunk_size;
 349         ENTRY;
 350
 351         LASSERT(handle->lgh_hdr == NULL);
 352
 353         LASSERT(chunk_size >= LLOG_MIN_CHUNK_SIZE);
 354         OBD_ALLOC_LARGE(llh, chunk_size);
 355         if (llh == NULL)
 356                 RETURN(-ENOMEM);
 357
 358         handle->lgh_hdr = llh;
 359         handle->lgh_hdr_size = chunk_size;
 360         /* first assign flags to use llog_client_ops */
 361         llh->llh_flags = flags;
 362         rc = llog_read_header(env, handle, uuid);
 363         if (rc == 0) {
 364                 if (unlikely((llh->llh_flags & LLOG_F_IS_PLAIN &&
 365                               flags & LLOG_F_IS_CAT) ||
 366                              (llh->llh_flags & LLOG_F_IS_CAT &&
 367                               flags & LLOG_F_IS_PLAIN))) {
 368                         CERROR("%s: llog type is %s but initializing %s\n",
 369                                handle->lgh_ctxt->loc_obd->obd_name,
 370                                llh->llh_flags & LLOG_F_IS_CAT ?
 371                                "catalog" : "plain",
 372                                flags & LLOG_F_IS_CAT ? "catalog" : "plain");
 373                         GOTO(out, rc = -EINVAL);
 374                 } else if (llh->llh_flags &
 375                            (LLOG_F_IS_PLAIN | LLOG_F_IS_CAT)) {
 376                         /*
 377                          * it is possible to open llog without specifying llog
 378                          * type so it is taken from llh_flags
 379                          */
 380                         flags = llh->llh_flags;
 381                 } else {
 382                         /* for some reason the llh_flags has no type set */
 383                         CERROR("llog type is not specified!\n");
 384                         GOTO(out, rc = -EINVAL);
 385                 }
 386                 if (unlikely(uuid &&
 387                              !obd_uuid_equals(uuid, &llh->llh_tgtuuid))) {
 388                         CERROR("%s: llog uuid mismatch: %s/%s\n",
 389                                handle->lgh_ctxt->loc_obd->obd_name,
 390                                (char *)uuid->uuid,
 391                                (char *)llh->llh_tgtuuid.uuid);
 392                         GOTO(out, rc = -EEXIST);
 393                 }
 394         }
 395         if (flags & LLOG_F_IS_CAT) {
 396                 LASSERT(list_empty(&handle->u.chd.chd_head));
 397                 INIT_LIST_HEAD(&handle->u.chd.chd_head);
 398                 llh->llh_size = sizeof(struct llog_logid_rec);
 399                 llh->llh_flags |= LLOG_F_IS_FIXSIZE;
 400         } else if (!(flags & LLOG_F_IS_PLAIN)) {
 401                 CERROR("%s: unknown flags: %#x (expected %#x or %#x)\n",
 402                        handle->lgh_ctxt->loc_obd->obd_name,
 403                        flags, LLOG_F_IS_CAT, LLOG_F_IS_PLAIN);
 404                 rc = -EINVAL;
 405         }
 406         llh->llh_flags |= fmt;
 407 out:
 408         if (rc) {
 409                 OBD_FREE_LARGE(llh, chunk_size);
 410                 handle->lgh_hdr = NULL;
 411         }
 412         RETURN(rc);
 413 }
 414 EXPORT_SYMBOL(llog_init_handle);
 415
 416 static int llog_process_thread(void *arg)
 417 {
 418         struct llog_process_info        *lpi = arg;
 419         struct llog_handle              *loghandle = lpi->lpi_loghandle;
 420         struct llog_log_hdr             *llh = loghandle->lgh_hdr;
 421         struct llog_process_cat_data    *cd  = lpi->lpi_catdata;
 422         char                            *buf;
 423         size_t                           chunk_size;
 424         __u64                            cur_offset, tmp_offset;
 425         int                              rc = 0, index = 1, last_index;
 426         int                              saved_index = 0;
 427         int                              last_called_index = 0;
 428
 429         ENTRY;
 430
 431         if (llh == NULL)
 432                 RETURN(-EINVAL);
 433
 434         cur_offset = chunk_size = llh->llh_hdr.lrh_len;
 435         /* expect chunk_size to be power of two */
 436         LASSERT(is_power_of_2(chunk_size));
 437
 438         OBD_ALLOC_LARGE(buf, chunk_size);
 439         if (buf == NULL) {
 440                 lpi->lpi_rc = -ENOMEM;
 441                 RETURN(0);
 442         }
 443
 444         if (cd != NULL) {
 445                 last_called_index = cd->lpcd_first_idx;
 446                 index = cd->lpcd_first_idx + 1;
 447         }
 448         if (cd != NULL && cd->lpcd_last_idx)
 449                 last_index = cd->lpcd_last_idx;
 450         else
 451                 last_index = LLOG_HDR_BITMAP_SIZE(llh) - 1;
 452
 453         while (rc == 0) {
 454                 struct llog_rec_hdr *rec;
 455                 off_t chunk_offset;
 456                 unsigned int buf_offset = 0;
 457                 bool partial_chunk;
 458
 459                 /* skip records not set in bitmap */
 460                 while (index <= last_index &&
 461                        !ext2_test_bit(index, LLOG_HDR_BITMAP(llh)))
 462                         ++index;
 463
 464                 /* There are no indices prior the last_index */
 465                 if (index > last_index)
 466                         break;
 467
 468                 CDEBUG(D_OTHER, "index: %d last_index %d\n", index,
 469                        last_index);
 470
 471 repeat:
 472                 /* get the buf with our target record; avoid old garbage */
 473                 memset(buf, 0, chunk_size);
 474                 rc = llog_next_block(lpi->lpi_env, loghandle, &saved_index,
 475                                      index, &cur_offset, buf, chunk_size);
 476                 if (rc != 0)
 477                         GOTO(out, rc);
 478
 479                 /* NB: after llog_next_block() call the cur_offset is the
 480                  * offset of the next block after read one.
 481                  * The absolute offset of the current chunk is calculated
 482                  * from cur_offset value and stored in chunk_offset variable.
 483                  */
 484                 tmp_offset = cur_offset;
 485                 if (do_div(tmp_offset, chunk_size) != 0) {
 486                         partial_chunk = true;
 487                         chunk_offset = cur_offset & ~(chunk_size - 1);
 488                 } else {
 489                         partial_chunk = false;
 490                         chunk_offset = cur_offset - chunk_size;
 491                 }
 492
 493                 /* NB: when rec->lrh_len is accessed it is already swabbed
 494                  * since it is used at the "end" of the loop and the rec
 495                  * swabbing is done at the beginning of the loop. */
 496                 for (rec = (struct llog_rec_hdr *)(buf + buf_offset);
 497                      (char *)rec < buf + chunk_size;
 498                      rec = llog_rec_hdr_next(rec)) {
 499
 500                         CDEBUG(D_OTHER, "processing rec 0x%p type %#x\n",
 501                                rec, rec->lrh_type);
 502
 503                         if (LLOG_REC_HDR_NEEDS_SWABBING(rec))
 504                                 lustre_swab_llog_rec(rec);
 505
 506                         CDEBUG(D_OTHER, "after swabbing, type=%#x idx=%d\n",
 507                                rec->lrh_type, rec->lrh_index);
 508
 509                         /* for partial chunk the end of it is zeroed, check
 510                          * for index 0 to distinguish it. */
 511                         if (partial_chunk && rec->lrh_index == 0) {
 512                                 /* concurrent llog_add() might add new records
 513                                  * while llog_processing, check this is not
 514                                  * the case and re-read the current chunk
 515                                  * otherwise. */
 516                                 int records;
 517                                 if (index > loghandle->lgh_last_idx)
 518                                         GOTO(out, rc = 0);
 519                                 /* <2 records means no more records
 520                                  * if the last record we processed was
 521                                  * the final one, then the underlying
 522                                  * object might have been destroyed yet.
 523                                  * we better don't access that.. */
 524                                 mutex_lock(&loghandle->lgh_hdr_mutex);
 525                                 records = loghandle->lgh_hdr->llh_count;
 526                                 mutex_unlock(&loghandle->lgh_hdr_mutex);
 527                                 if (records <= 1)
 528                                         GOTO(out, rc = 0);
 529                                 CDEBUG(D_OTHER, "Re-read last llog buffer for "
 530                                        "new records, index %u, last %u\n",
 531                                        index, loghandle->lgh_last_idx);
 532                                 /* save offset inside buffer for the re-read */
 533                                 buf_offset = (char *)rec - (char *)buf;
 534                                 cur_offset = chunk_offset;
 535                                 goto repeat;
 536                         }
 537
 538                         if (rec->lrh_len == 0 || rec->lrh_len > chunk_size) {
 539                                 CWARN("%s: invalid length %d in llog "DFID
 540                                       "record for index %d/%d\n",
 541                                        loghandle->lgh_ctxt->loc_obd->obd_name,
 542                                        rec->lrh_len,
 543                                        PFID(&loghandle->lgh_id.lgl_oi.oi_fid),
 544                                        rec->lrh_index, index);
 545
 546                                 GOTO(out, rc = -EINVAL);
 547                         }
 548
 549                         if (rec->lrh_index < index) {
 550                                 CDEBUG(D_OTHER, "skipping lrh_index %d\n",
 551                                        rec->lrh_index);
 552                                 continue;
 553                         }
 554
 555                         if (rec->lrh_index != index) {
 556                                 CERROR("%s: "DFID" Invalid record: index %u"
 557                                        " but expected %u\n",
 558                                        loghandle->lgh_ctxt->loc_obd->obd_name,
 559                                        PFID(&loghandle->lgh_id.lgl_oi.oi_fid),
 560                                        rec->lrh_index, index);
 561                                 GOTO(out, rc = -ERANGE);
 562                         }
 563
 564                         CDEBUG(D_OTHER,
 565                                "lrh_index: %d lrh_len: %d (%d remains)\n",
 566                                rec->lrh_index, rec->lrh_len,
 567                                (int)(buf + chunk_size - (char *)rec));
 568
 569                         loghandle->lgh_cur_idx = rec->lrh_index;
 570                         loghandle->lgh_cur_offset = (char *)rec - (char *)buf +
 571                                                     chunk_offset;
 572
 573                         /* if set, process the callback on this record */
 574                         if (ext2_test_bit(index, LLOG_HDR_BITMAP(llh))) {
 575                                 rc = lpi->lpi_cb(lpi->lpi_env, loghandle, rec,
 576                                                  lpi->lpi_cbdata);
 577                                 last_called_index = index;
 578                                 if (rc == LLOG_PROC_BREAK) {
 579                                         GOTO(out, rc);
 580                                 } else if (rc == LLOG_DEL_RECORD) {
 581                                         rc = llog_cancel_rec(lpi->lpi_env,
 582                                                              loghandle,
 583                                                              rec->lrh_index);
 584                                 }
 585                                 if (rc)
 586                                         GOTO(out, rc);
 587                         }
 588                         /* exit if the last index is reached */
 589                         if (index >= last_index)
 590                                 GOTO(out, rc = 0);
 591                         ++index;
 592                 }
 593         }
 594
 595 out:
 596         if (cd != NULL)
 597                 cd->lpcd_last_idx = last_called_index;
 598
 599         if (unlikely(rc == -EIO && loghandle->lgh_obj != NULL)) {
 600                 if (dt_object_remote(loghandle->lgh_obj)) {
 601                         /* If it is remote object, then -EIO might means
 602                          * disconnection or eviction, let's return -EAGAIN,
 603                          * so for update recovery log processing, it will
 604                          * retry until the umount or abort recovery, see
 605                          * lod_sub_recovery_thread() */
 606                         CERROR("%s retry remote llog process\n",
 607                                loghandle->lgh_ctxt->loc_obd->obd_name);
 608                         rc = -EAGAIN;
 609                 } else {
 610                         /* something bad happened to the processing of a local
 611                          * llog file, probably I/O error or the log got
 612                          * corrupted to be able to finally release the log we
 613                          * discard any remaining bits in the header */
 614                         CERROR("Local llog found corrupted\n");
 615                         while (index <= last_index) {
 616                                 if (ext2_test_bit(index,
 617                                                   LLOG_HDR_BITMAP(llh)) != 0)
 618                                         llog_cancel_rec(lpi->lpi_env, loghandle,
 619                                                         index);
 620                                 index++;
 621                         }
 622                         rc = 0;
 623                 }
 624         }
 625
 626         OBD_FREE_LARGE(buf, chunk_size);
 627         lpi->lpi_rc = rc;
 628         return 0;
 629 }
 630
 631 static int llog_process_thread_daemonize(void *arg)
 632 {
 633         struct llog_process_info        *lpi = arg;
 634         struct lu_env                    env;
 635         int                              rc;
 636         struct nsproxy                  *new_ns, *curr_ns = current->nsproxy;
 637
 638         task_lock(lpi->lpi_reftask);
 639         new_ns = lpi->lpi_reftask->nsproxy;
 640         if (curr_ns != new_ns) {
 641                 get_nsproxy(new_ns);
 642
 643                 current->nsproxy = new_ns;
 644                 /* XXX: we should call put_nsproxy() instead of
 645                  * atomic_dec(&ns->count) directly. But put_nsproxy() cannot be
 646                  * used outside of the kernel itself, because it calls
 647                  * free_nsproxy() which is not exported by the kernel
 648                  * (defined in kernel/nsproxy.c) */
 649                 atomic_dec(&curr_ns->count);
 650         }
 651         task_unlock(lpi->lpi_reftask);
 652
 653         unshare_fs_struct();
 654
 655         /* client env has no keys, tags is just 0 */
 656         rc = lu_env_init(&env, LCT_LOCAL | LCT_MG_THREAD);
 657         if (rc)
 658                 goto out;
 659         lpi->lpi_env = &env;
 660
 661         rc = llog_process_thread(arg);
 662
 663         lu_env_fini(&env);
 664 out:
 665         complete(&lpi->lpi_completion);
 666         return rc;
 667 }
 668
 669 int llog_process_or_fork(const struct lu_env *env,
 670                          struct llog_handle *loghandle,
 671                          llog_cb_t cb, void *data, void *catdata, bool fork)
 672 {
 673         struct llog_process_info *lpi;
 674         int                      rc;
 675
 676         ENTRY;
 677
 678         OBD_ALLOC_PTR(lpi);
 679         if (lpi == NULL) {
 680                 CERROR("cannot alloc pointer\n");
 681                 RETURN(-ENOMEM);
 682         }
 683         lpi->lpi_loghandle = loghandle;
 684         lpi->lpi_cb        = cb;
 685         lpi->lpi_cbdata    = data;
 686         lpi->lpi_catdata   = catdata;
 687
 688         if (fork) {
 689                 struct task_struct *task;
 690
 691                 /* The new thread can't use parent env,
 692                  * init the new one in llog_process_thread_daemonize. */
 693                 lpi->lpi_env = NULL;
 694                 init_completion(&lpi->lpi_completion);
 695                 /* take reference to current, so that
 696                  * llog_process_thread_daemonize() can use it to switch to
 697                  * namespace associated with current  */
 698                 lpi->lpi_reftask = current;
 699                 task = kthread_run(llog_process_thread_daemonize, lpi,
 700                                    "llog_process_thread");
 701                 if (IS_ERR(task)) {
 702                         rc = PTR_ERR(task);
 703                         CERROR("%s: cannot start thread: rc = %d\n",
 704                                loghandle->lgh_ctxt->loc_obd->obd_name, rc);
 705                         GOTO(out_lpi, rc);
 706                 }
 707                 wait_for_completion(&lpi->lpi_completion);
 708         } else {
 709                 lpi->lpi_env = env;
 710                 llog_process_thread(lpi);
 711         }
 712         rc = lpi->lpi_rc;
 713
 714 out_lpi:
 715         OBD_FREE_PTR(lpi);
 716         RETURN(rc);
 717 }
 718 EXPORT_SYMBOL(llog_process_or_fork);
 719
 720 int llog_process(const struct lu_env *env, struct llog_handle *loghandle,
 721                  llog_cb_t cb, void *data, void *catdata)
 722 {
 723         int rc;
 724         rc = llog_process_or_fork(env, loghandle, cb, data, catdata, true);
 725         return rc == LLOG_DEL_PLAIN ? 0 : rc;
 726 }
 727 EXPORT_SYMBOL(llog_process);
 728
 729 int llog_reverse_process(const struct lu_env *env,
 730                          struct llog_handle *loghandle, llog_cb_t cb,
 731                          void *data, void *catdata)
 732 {
 733         struct llog_log_hdr *llh = loghandle->lgh_hdr;
 734         struct llog_process_cat_data *cd = catdata;
 735         void *buf;
 736         int rc = 0, first_index = 1, index, idx;
 737         __u32   chunk_size = llh->llh_hdr.lrh_len;
 738         ENTRY;
 739
 740         OBD_ALLOC_LARGE(buf, chunk_size);
 741         if (buf == NULL)
 742                 RETURN(-ENOMEM);
 743
 744         if (cd != NULL)
 745                 first_index = cd->lpcd_first_idx + 1;
 746         if (cd != NULL && cd->lpcd_last_idx)
 747                 index = cd->lpcd_last_idx;
 748         else
 749                 index = LLOG_HDR_BITMAP_SIZE(llh) - 1;
 750
 751         while (rc == 0) {
 752                 struct llog_rec_hdr *rec;
 753                 struct llog_rec_tail *tail;
 754
 755                 /* skip records not set in bitmap */
 756                 while (index >= first_index &&
 757                        !ext2_test_bit(index, LLOG_HDR_BITMAP(llh)))
 758                         --index;
 759
 760                 LASSERT(index >= first_index - 1);
 761                 if (index == first_index - 1)
 762                         break;
 763
 764                 /* get the buf with our target record; avoid old garbage */
 765                 memset(buf, 0, chunk_size);
 766                 rc = llog_prev_block(env, loghandle, index, buf, chunk_size);
 767                 if (rc)
 768                         GOTO(out, rc);
 769
 770                 rec = buf;
 771                 idx = rec->lrh_index;
 772                 CDEBUG(D_RPCTRACE, "index %u : idx %u\n", index, idx);
 773                 while (idx < index) {
 774                         rec = (void *)rec + rec->lrh_len;
 775                         if (LLOG_REC_HDR_NEEDS_SWABBING(rec))
 776                                 lustre_swab_llog_rec(rec);
 777                         idx ++;
 778                 }
 779                 LASSERT(idx == index);
 780                 tail = (void *)rec + rec->lrh_len - sizeof(*tail);
 781
 782                 /* process records in buffer, starting where we found one */
 783                 while ((void *)tail > buf) {
 784                         if (tail->lrt_index == 0)
 785                                 GOTO(out, rc = 0); /* no more records */
 786
 787                         /* if set, process the callback on this record */
 788                         if (ext2_test_bit(index, LLOG_HDR_BITMAP(llh))) {
 789                                 rec = (void *)tail - tail->lrt_len +
 790                                       sizeof(*tail);
 791
 792                                 rc = cb(env, loghandle, rec, data);
 793                                 if (rc == LLOG_PROC_BREAK) {
 794                                         GOTO(out, rc);
 795                                 } else if (rc == LLOG_DEL_RECORD) {
 796                                         rc = llog_cancel_rec(env, loghandle,
 797                                                              tail->lrt_index);
 798                                 }
 799                                 if (rc)
 800                                         GOTO(out, rc);
 801                         }
 802
 803                         /* previous record, still in buffer? */
 804                         --index;
 805                         if (index < first_index)
 806                                 GOTO(out, rc = 0);
 807                         tail = (void *)tail - tail->lrt_len;
 808                 }
 809         }
 810
 811 out:
 812         if (buf != NULL)
 813                 OBD_FREE_LARGE(buf, chunk_size);
 814         RETURN(rc);
 815 }
 816 EXPORT_SYMBOL(llog_reverse_process);
 817
 818 /**
 819  * new llog API
 820  *
 821  * API functions:
 822  *      llog_open - open llog, may not exist
 823  *      llog_exist - check if llog exists
 824  *      llog_close - close opened llog, pair for open, frees llog_handle
 825  *      llog_declare_create - declare llog creation
 826  *      llog_create - create new llog on disk, need transaction handle
 827  *      llog_declare_write_rec - declaration of llog write
 828  *      llog_write_rec - write llog record on disk, need transaction handle
 829  *      llog_declare_add - declare llog catalog record addition
 830  *      llog_add - add llog record in catalog, need transaction handle
 831  */
 832 int llog_exist(struct llog_handle *loghandle)
 833 {
 834         struct llog_operations  *lop;
 835         int                      rc;
 836
 837         ENTRY;
 838
 839         rc = llog_handle2ops(loghandle, &lop);
 840         if (rc)
 841                 RETURN(rc);
 842         if (lop->lop_exist == NULL)
 843                 RETURN(-EOPNOTSUPP);
 844
 845         rc = lop->lop_exist(loghandle);
 846         RETURN(rc);
 847 }
 848 EXPORT_SYMBOL(llog_exist);
 849
 850 int llog_declare_create(const struct lu_env *env,
 851                         struct llog_handle *loghandle, struct thandle *th)
 852 {
 853         struct llog_operations  *lop;
 854         int                      raised, rc;
 855
 856         ENTRY;
 857
 858         rc = llog_handle2ops(loghandle, &lop);
 859         if (rc)
 860                 RETURN(rc);
 861         if (lop->lop_declare_create == NULL)
 862                 RETURN(-EOPNOTSUPP);
 863
 864         raised = cfs_cap_raised(CFS_CAP_SYS_RESOURCE);
 865         if (!raised)
 866                 cfs_cap_raise(CFS_CAP_SYS_RESOURCE);
 867         rc = lop->lop_declare_create(env, loghandle, th);
 868         if (!raised)
 869                 cfs_cap_lower(CFS_CAP_SYS_RESOURCE);
 870         RETURN(rc);
 871 }
 872
 873 int llog_create(const struct lu_env *env, struct llog_handle *handle,
 874                 struct thandle *th)
 875 {
 876         struct llog_operations  *lop;
 877         int                      raised, rc;
 878
 879         ENTRY;
 880
 881         rc = llog_handle2ops(handle, &lop);
 882         if (rc)
 883                 RETURN(rc);
 884         if (lop->lop_create == NULL)
 885                 RETURN(-EOPNOTSUPP);
 886
 887         raised = cfs_cap_raised(CFS_CAP_SYS_RESOURCE);
 888         if (!raised)
 889                 cfs_cap_raise(CFS_CAP_SYS_RESOURCE);
 890         rc = lop->lop_create(env, handle, th);
 891         if (!raised)
 892                 cfs_cap_lower(CFS_CAP_SYS_RESOURCE);
 893         RETURN(rc);
 894 }
 895
 896 int llog_declare_write_rec(const struct lu_env *env,
 897                            struct llog_handle *handle,
 898                            struct llog_rec_hdr *rec, int idx,
 899                            struct thandle *th)
 900 {
 901         struct llog_operations  *lop;
 902         int                      raised, rc;
 903
 904         ENTRY;
 905
 906         rc = llog_handle2ops(handle, &lop);
 907         if (rc)
 908                 RETURN(rc);
 909         LASSERT(lop);
 910         if (lop->lop_declare_write_rec == NULL)
 911                 RETURN(-EOPNOTSUPP);
 912
 913         raised = cfs_cap_raised(CFS_CAP_SYS_RESOURCE);
 914         if (!raised)
 915                 cfs_cap_raise(CFS_CAP_SYS_RESOURCE);
 916         rc = lop->lop_declare_write_rec(env, handle, rec, idx, th);
 917         if (!raised)
 918                 cfs_cap_lower(CFS_CAP_SYS_RESOURCE);
 919         RETURN(rc);
 920 }
 921
 922 int llog_write_rec(const struct lu_env *env, struct llog_handle *handle,
 923                    struct llog_rec_hdr *rec, struct llog_cookie *logcookies,
 924                    int idx, struct thandle *th)
 925 {
 926         struct llog_operations  *lop;
 927         int                      raised, rc, buflen;
 928
 929         ENTRY;
 930
 931         /* API sanity checks */
 932         if (handle == NULL) {
 933                 CERROR("loghandle is missed\n");
 934                 RETURN(-EPROTO);
 935         } else if (handle->lgh_obj == NULL) {
 936                 CERROR("loghandle %p with NULL object\n",
 937                         handle);
 938                 RETURN(-EPROTO);
 939         } else if (th == NULL) {
 940                 CERROR("%s: missed transaction handle\n",
 941                         handle->lgh_obj->do_lu.lo_dev->ld_obd->obd_name);
 942                 RETURN(-EPROTO);
 943         } else if (handle->lgh_hdr == NULL) {
 944                 CERROR("%s: loghandle %p with no header\n",
 945                         handle->lgh_obj->do_lu.lo_dev->ld_obd->obd_name,
 946                         handle);
 947                 RETURN(-EPROTO);
 948         }
 949
 950         rc = llog_handle2ops(handle, &lop);
 951         if (rc)
 952                 RETURN(rc);
 953
 954         if (lop->lop_write_rec == NULL)
 955                 RETURN(-EOPNOTSUPP);
 956
 957         buflen = rec->lrh_len;
 958         LASSERT(cfs_size_round(buflen) == buflen);
 959
 960         raised = cfs_cap_raised(CFS_CAP_SYS_RESOURCE);
 961         if (!raised)
 962                 cfs_cap_raise(CFS_CAP_SYS_RESOURCE);
 963         rc = lop->lop_write_rec(env, handle, rec, logcookies, idx, th);
 964         if (!raised)
 965                 cfs_cap_lower(CFS_CAP_SYS_RESOURCE);
 966         RETURN(rc);
 967 }
 968
 969 int llog_add(const struct lu_env *env, struct llog_handle *lgh,
 970              struct llog_rec_hdr *rec, struct llog_cookie *logcookies,
 971              struct thandle *th)
 972 {
 973         int raised, rc;
 974
 975         ENTRY;
 976
 977         if (lgh->lgh_logops->lop_add == NULL)
 978                 RETURN(-EOPNOTSUPP);
 979
 980         raised = cfs_cap_raised(CFS_CAP_SYS_RESOURCE);
 981         if (!raised)
 982                 cfs_cap_raise(CFS_CAP_SYS_RESOURCE);
 983         rc = lgh->lgh_logops->lop_add(env, lgh, rec, logcookies, th);
 984         if (!raised)
 985                 cfs_cap_lower(CFS_CAP_SYS_RESOURCE);
 986         RETURN(rc);
 987 }
 988 EXPORT_SYMBOL(llog_add);
 989
 990 int llog_declare_add(const struct lu_env *env, struct llog_handle *lgh,
 991                      struct llog_rec_hdr *rec, struct thandle *th)
 992 {
 993         int raised, rc;
 994
 995         ENTRY;
 996
 997         if (lgh->lgh_logops->lop_declare_add == NULL)
 998                 RETURN(-EOPNOTSUPP);
 999
1000         raised = cfs_cap_raised(CFS_CAP_SYS_RESOURCE);
1001         if (!raised)
1002                 cfs_cap_raise(CFS_CAP_SYS_RESOURCE);
1003         rc = lgh->lgh_logops->lop_declare_add(env, lgh, rec, th);
1004         if (!raised)
1005                 cfs_cap_lower(CFS_CAP_SYS_RESOURCE);
1006         RETURN(rc);
1007 }
1008 EXPORT_SYMBOL(llog_declare_add);
1009
1010 /**
1011  * Helper function to open llog or create it if doesn't exist.
1012  * It hides all transaction handling from caller.
1013  */
1014 int llog_open_create(const struct lu_env *env, struct llog_ctxt *ctxt,
1015                      struct llog_handle **res, struct llog_logid *logid,
1016                      char *name)
1017 {
1018         struct dt_device        *d;
1019         struct thandle          *th;
1020         int                      rc;
1021
1022         ENTRY;
1023
1024         rc = llog_open(env, ctxt, res, logid, name, LLOG_OPEN_NEW);
1025         if (rc)
1026                 RETURN(rc);
1027
1028         if (llog_exist(*res))
1029                 RETURN(0);
1030
1031         LASSERT((*res)->lgh_obj != NULL);
1032
1033         d = lu2dt_dev((*res)->lgh_obj->do_lu.lo_dev);
1034
1035         th = dt_trans_create(env, d);
1036         if (IS_ERR(th))
1037                 GOTO(out, rc = PTR_ERR(th));
1038
1039         /* Create update llog object synchronously, which
1040          * happens during inialization process see
1041          * lod_sub_prep_llog(), to make sure the update
1042          * llog object is created before corss-MDT writing
1043          * updates into the llog object */
1044         if (ctxt->loc_flags & LLOG_CTXT_FLAG_NORMAL_FID)
1045                 th->th_sync = 1;
1046
1047         th->th_wait_submit = 1;
1048         rc = llog_declare_create(env, *res, th);
1049         if (rc == 0) {
1050                 rc = dt_trans_start_local(env, d, th);
1051                 if (rc == 0)
1052                         rc = llog_create(env, *res, th);
1053         }
1054         dt_trans_stop(env, d, th);
1055 out:
1056         if (rc)
1057                 llog_close(env, *res);
1058         RETURN(rc);
1059 }
1060 EXPORT_SYMBOL(llog_open_create);
1061
1062 /**
1063  * Helper function to delete existent llog.
1064  */
1065 int llog_erase(const struct lu_env *env, struct llog_ctxt *ctxt,
1066                struct llog_logid *logid, char *name)
1067 {
1068         struct llog_handle      *handle;
1069         int                      rc = 0, rc2;
1070
1071         ENTRY;
1072
1073         /* nothing to erase */
1074         if (name == NULL && logid == NULL)
1075                 RETURN(0);
1076
1077         rc = llog_open(env, ctxt, &handle, logid, name, LLOG_OPEN_EXISTS);
1078         if (rc < 0)
1079                 RETURN(rc);
1080
1081         rc = llog_init_handle(env, handle, LLOG_F_IS_PLAIN, NULL);
1082         if (rc == 0)
1083                 rc = llog_destroy(env, handle);
1084
1085         rc2 = llog_close(env, handle);
1086         if (rc == 0)
1087                 rc = rc2;
1088         RETURN(rc);
1089 }
1090 EXPORT_SYMBOL(llog_erase);
1091
1092 /*
1093  * Helper function for write record in llog.
1094  * It hides all transaction handling from caller.
1095  * Valid only with local llog.
1096  */
1097 int llog_write(const struct lu_env *env, struct llog_handle *loghandle,
1098                struct llog_rec_hdr *rec, int idx)
1099 {
1100         struct dt_device        *dt;
1101         struct thandle          *th;
1102         int                      rc;
1103
1104         ENTRY;
1105
1106         LASSERT(loghandle);
1107         LASSERT(loghandle->lgh_ctxt);
1108         LASSERT(loghandle->lgh_obj != NULL);
1109
1110         dt = lu2dt_dev(loghandle->lgh_obj->do_lu.lo_dev);
1111
1112         th = dt_trans_create(env, dt);
1113         if (IS_ERR(th))
1114                 RETURN(PTR_ERR(th));
1115
1116         rc = llog_declare_write_rec(env, loghandle, rec, idx, th);
1117         if (rc)
1118                 GOTO(out_trans, rc);
1119
1120         th->th_wait_submit = 1;
1121         rc = dt_trans_start_local(env, dt, th);
1122         if (rc)
1123                 GOTO(out_trans, rc);
1124
1125         down_write(&loghandle->lgh_lock);
1126         rc = llog_write_rec(env, loghandle, rec, NULL, idx, th);
1127         up_write(&loghandle->lgh_lock);
1128 out_trans:
1129         dt_trans_stop(env, dt, th);
1130         RETURN(rc);
1131 }
1132 EXPORT_SYMBOL(llog_write);
1133
1134 int llog_open(const struct lu_env *env, struct llog_ctxt *ctxt,
1135               struct llog_handle **lgh, struct llog_logid *logid,
1136               char *name, enum llog_open_param open_param)
1137 {
1138         int      raised;
1139         int      rc;
1140
1141         ENTRY;
1142
1143         LASSERT(ctxt);
1144         LASSERT(ctxt->loc_logops);
1145
1146         if (ctxt->loc_logops->lop_open == NULL) {
1147                 *lgh = NULL;
1148                 RETURN(-EOPNOTSUPP);
1149         }
1150
1151         *lgh = llog_alloc_handle();
1152         if (*lgh == NULL)
1153                 RETURN(-ENOMEM);
1154         (*lgh)->lgh_ctxt = ctxt;
1155         (*lgh)->lgh_logops = ctxt->loc_logops;
1156
1157         raised = cfs_cap_raised(CFS_CAP_SYS_RESOURCE);
1158         if (!raised)
1159                 cfs_cap_raise(CFS_CAP_SYS_RESOURCE);
1160         rc = ctxt->loc_logops->lop_open(env, *lgh, logid, name, open_param);
1161         if (!raised)
1162                 cfs_cap_lower(CFS_CAP_SYS_RESOURCE);
1163         if (rc) {
1164                 llog_free_handle(*lgh);
1165                 *lgh = NULL;
1166         }
1167         RETURN(rc);
1168 }
1169 EXPORT_SYMBOL(llog_open);
1170
1171 int llog_close(const struct lu_env *env, struct llog_handle *loghandle)
1172 {
1173         struct llog_operations  *lop;
1174         int                      rc;
1175
1176         ENTRY;
1177
1178         rc = llog_handle2ops(loghandle, &lop);
1179         if (rc)
1180                 GOTO(out, rc);
1181         if (lop->lop_close == NULL)
1182                 GOTO(out, rc = -EOPNOTSUPP);
1183         rc = lop->lop_close(env, loghandle);
1184 out:
1185         llog_handle_put(loghandle);
1186         RETURN(rc);
1187 }
1188 EXPORT_SYMBOL(llog_close);
1189
1190 /**
1191  * Helper function to get the llog size in records. It is used by MGS
1192  * mostly to check that config llog exists and contains data.
1193  *
1194  * \param[in] env       execution environment
1195  * \param[in] ctxt      llog context
1196  * \param[in] name      llog name
1197  *
1198  * \retval              true if there are records in llog besides a header
1199  * \retval              false on error or llog without records
1200  */
1201 int llog_is_empty(const struct lu_env *env, struct llog_ctxt *ctxt,
1202                   char *name)
1203 {
1204         struct llog_handle      *llh;
1205         int                      rc = 0;
1206
1207         rc = llog_open(env, ctxt, &llh, NULL, name, LLOG_OPEN_EXISTS);
1208         if (rc < 0) {
1209                 if (likely(rc == -ENOENT))
1210                         rc = 0;
1211                 GOTO(out, rc);
1212         }
1213
1214         rc = llog_init_handle(env, llh, LLOG_F_IS_PLAIN, NULL);
1215         if (rc)
1216                 GOTO(out_close, rc);
1217         rc = llog_get_size(llh);
1218
1219 out_close:
1220         llog_close(env, llh);
1221 out:
1222         /* The header is record 1, the llog is still considered as empty
1223          * if there is only header */
1224         return (rc <= 1);
1225 }
1226 EXPORT_SYMBOL(llog_is_empty);
1227
1228 int llog_copy_handler(const struct lu_env *env, struct llog_handle *llh,
1229                       struct llog_rec_hdr *rec, void *data)
1230 {
1231         struct llog_handle      *copy_llh = data;
1232
1233         /* Append all records */
1234         return llog_write(env, copy_llh, rec, LLOG_NEXT_IDX);
1235 }
1236
1237 /* backup plain llog */
1238 int llog_backup(const struct lu_env *env, struct obd_device *obd,
1239                 struct llog_ctxt *ctxt, struct llog_ctxt *bctxt,
1240                 char *name, char *backup)
1241 {
1242         struct llog_handle      *llh, *bllh;
1243         int                      rc;
1244
1245         ENTRY;
1246
1247         /* open original log */
1248         rc = llog_open(env, ctxt, &llh, NULL, name, LLOG_OPEN_EXISTS);
1249         if (rc < 0) {
1250                 /* the -ENOENT case is also reported to the caller
1251                  * but silently so it should handle that if needed.
1252                  */
1253                 if (rc != -ENOENT)
1254                         CERROR("%s: failed to open log %s: rc = %d\n",
1255                                obd->obd_name, name, rc);
1256                 RETURN(rc);
1257         }
1258
1259         rc = llog_init_handle(env, llh, LLOG_F_IS_PLAIN, NULL);
1260         if (rc)
1261                 GOTO(out_close, rc);
1262
1263         /* Make sure there's no old backup log */
1264         rc = llog_erase(env, bctxt, NULL, backup);
1265         if (rc < 0 && rc != -ENOENT)
1266                 GOTO(out_close, rc);
1267
1268         /* open backup log */
1269         rc = llog_open_create(env, bctxt, &bllh, NULL, backup);
1270         if (rc) {
1271                 CERROR("%s: failed to open backup logfile %s: rc = %d\n",
1272                        obd->obd_name, backup, rc);
1273                 GOTO(out_close, rc);
1274         }
1275
1276         /* check that backup llog is not the same object as original one */
1277         if (llh->lgh_obj == bllh->lgh_obj) {
1278                 CERROR("%s: backup llog %s to itself (%s), objects %p/%p\n",
1279                        obd->obd_name, name, backup, llh->lgh_obj,
1280                        bllh->lgh_obj);
1281                 GOTO(out_backup, rc = -EEXIST);
1282         }
1283
1284         rc = llog_init_handle(env, bllh, LLOG_F_IS_PLAIN, NULL);
1285         if (rc)
1286                 GOTO(out_backup, rc);
1287
1288         /* Copy log record by record */
1289         rc = llog_process_or_fork(env, llh, llog_copy_handler, (void *)bllh,
1290                                   NULL, false);
1291         if (rc)
1292                 CERROR("%s: failed to backup log %s: rc = %d\n",
1293                        obd->obd_name, name, rc);
1294 out_backup:
1295         llog_close(env, bllh);
1296 out_close:
1297         llog_close(env, llh);
1298         RETURN(rc);
1299 }
1300 EXPORT_SYMBOL(llog_backup);
1301
1302 /* Get size of llog */
1303 __u64 llog_size(const struct lu_env *env, struct llog_handle *llh)
1304 {
1305         int rc;
1306         struct lu_attr la;
1307
1308         rc = llh->lgh_obj->do_ops->do_attr_get(env, llh->lgh_obj, &la);
1309         if (rc) {
1310                 CERROR("%s: attr_get failed, rc = %d\n",
1311                        llh->lgh_ctxt->loc_obd->obd_name, rc);
1312                 return 0;
1313         }
1314
1315         return la.la_size;
1316 }
1317 EXPORT_SYMBOL(llog_size);
1318