lustre/obdclass/llog_cat.c

   1 /* -*- mode: c; c-basic-offset: 8; indent-tabs-mode: nil; -*-
   2  * vim:expandtab:shiftwidth=8:tabstop=8:
   3  *
   4  *  Copyright (C) 2001-2003 Cluster File Systems, Inc.
   5  *   Author: Andreas Dilger <adilger@clusterfs.com>
   6  *
   7  *   This file is part of the Lustre file system, http://www.lustre.org
   8  *   Lustre is a trademark of Cluster File Systems, Inc.
   9  *
  10  *   You may have signed or agreed to another license before downloading
  11  *   this software.  If so, you are bound by the terms and conditions
  12  *   of that agreement, and the following does not apply to you.  See the
  13  *   LICENSE file included with this distribution for more information.
  14  *
  15  *   If you did not agree to a different license, then this copy of Lustre
  16  *   is open source software; you can redistribute it and/or modify it
  17  *   under the terms of version 2 of the GNU General Public License as
  18  *   published by the Free Software Foundation.
  19  *
  20  *   In either case, Lustre is distributed in the hope that it will be
  21  *   useful, but WITHOUT ANY WARRANTY; without even the implied warranty
  22  *   of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  23  *   license text for more details.
  24  *
  25  * OST<->MDS recovery logging infrastructure.
  26  *
  27  * Invariants in implementation:
  28  * - we do not share logs among different OST<->MDS connections, so that
  29  *   if an OST or MDS fails it need only look at log(s) relevant to itself
  30  */
  31
  32 #define DEBUG_SUBSYSTEM S_LOG
  33
  34 #ifndef EXPORT_SYMTAB
  35 #define EXPORT_SYMTAB
  36 #endif
  37
  38 #ifndef __KERNEL__
  39 #include <liblustre.h>
  40 #endif
  41
  42 #include <obd_class.h>
  43 #include <lustre_log.h>
  44 #include <libcfs/list.h>
  45
  46 /* Create a new log handle and add it to the open list.
  47  * This log handle will be closed when all of the records in it are removed.
  48  *
  49  * Assumes caller has already pushed us into the kernel context and is locking.
  50  */
  51 static struct llog_handle *llog_cat_new_log(struct llog_handle *cathandle)
  52 {
  53         struct llog_handle *loghandle;
  54         struct llog_log_hdr *llh;
  55         struct llog_logid_rec rec = { { 0 }, };
  56         int rc, index, bitmap_size;
  57         ENTRY;
  58
  59         llh = cathandle->lgh_hdr;
  60         bitmap_size = LLOG_BITMAP_SIZE(llh);
  61
  62         index = (cathandle->lgh_last_idx + 1) % bitmap_size;
  63
  64         /* maximum number of available slots in catlog is bitmap_size - 2 */
  65         if (llh->llh_cat_idx == index) {
  66                 CERROR("no free catalog slots for log...\n");
  67                 RETURN(ERR_PTR(-ENOSPC));
  68         }
  69
  70         if (OBD_FAIL_CHECK(OBD_FAIL_MDS_LLOG_CREATE_FAILED))
  71                 RETURN(ERR_PTR(-ENOSPC));
  72
  73         rc = llog_create(cathandle->lgh_ctxt, &loghandle, NULL, NULL);
  74         if (rc)
  75                 RETURN(ERR_PTR(rc));
  76
  77         rc = llog_init_handle(loghandle,
  78                               LLOG_F_IS_PLAIN | LLOG_F_ZAP_WHEN_EMPTY,
  79                               &cathandle->lgh_hdr->llh_tgtuuid);
  80         if (rc)
  81                 GOTO(out_destroy, rc);
  82
  83         if (index == 0)
  84                 index = 1;
  85         if (ext2_set_bit(index, llh->llh_bitmap)) {
  86                 CERROR("argh, index %u already set in log bitmap?\n",
  87                        index);
  88                 LBUG(); /* should never happen */
  89         }
  90         cathandle->lgh_last_idx = index;
  91         llh->llh_count++;
  92         llh->llh_tail.lrt_index = index;
  93
  94         CDEBUG(D_RPCTRACE,"new recovery log "LPX64":%x for index %u of catalog "
  95                LPX64"\n", loghandle->lgh_id.lgl_oid, loghandle->lgh_id.lgl_ogen,
  96                index, cathandle->lgh_id.lgl_oid);
  97         /* build the record for this log in the catalog */
  98         rec.lid_hdr.lrh_len = sizeof(rec);
  99         rec.lid_hdr.lrh_index = index;
 100         rec.lid_hdr.lrh_type = LLOG_LOGID_MAGIC;
 101         rec.lid_id = loghandle->lgh_id;
 102         rec.lid_tail.lrt_len = sizeof(rec);
 103         rec.lid_tail.lrt_index = index;
 104
 105         /* update the catalog: header and record */
 106         rc = llog_write_rec(cathandle, &rec.lid_hdr,
 107                             &loghandle->u.phd.phd_cookie, 1, NULL, index);
 108         if (rc < 0) {
 109                 GOTO(out_destroy, rc);
 110         }
 111
 112         loghandle->lgh_hdr->llh_cat_idx = index;
 113         cathandle->u.chd.chd_current_log = loghandle;
 114         LASSERT(list_empty(&loghandle->u.phd.phd_entry));
 115         list_add_tail(&loghandle->u.phd.phd_entry, &cathandle->u.chd.chd_head);
 116
 117  out_destroy:
 118         if (rc < 0)
 119                 llog_destroy(loghandle);
 120
 121         RETURN(loghandle);
 122 }
 123 EXPORT_SYMBOL(llog_cat_new_log);
 124
 125 /* Open an existent log handle and add it to the open list.
 126  * This log handle will be closed when all of the records in it are removed.
 127  *
 128  * Assumes caller has already pushed us into the kernel context and is locking.
 129  * We return a lock on the handle to ensure nobody yanks it from us.
 130  */
 131 int llog_cat_id2handle(struct llog_handle *cathandle, struct llog_handle **res,
 132                        struct llog_logid *logid)
 133 {
 134         struct llog_handle *loghandle;
 135         int rc = 0;
 136         ENTRY;
 137
 138         if (cathandle == NULL)
 139                 RETURN(-EBADF);
 140
 141         list_for_each_entry(loghandle, &cathandle->u.chd.chd_head,
 142                             u.phd.phd_entry) {
 143                 struct llog_logid *cgl = &loghandle->lgh_id;
 144                 if (cgl->lgl_oid == logid->lgl_oid) {
 145                         if (cgl->lgl_ogen != logid->lgl_ogen) {
 146                                 CERROR("log "LPX64" generation %x != %x\n",
 147                                        logid->lgl_oid, cgl->lgl_ogen,
 148                                        logid->lgl_ogen);
 149                                 continue;
 150                         }
 151                         loghandle->u.phd.phd_cat_handle = cathandle;
 152                         GOTO(out, rc = 0);
 153                 }
 154         }
 155
 156         rc = llog_create(cathandle->lgh_ctxt, &loghandle, logid, NULL);
 157         if (rc) {
 158                 CERROR("error opening log id "LPX64":%x: rc %d\n",
 159                        logid->lgl_oid, logid->lgl_ogen, rc);
 160         } else {
 161                 rc = llog_init_handle(loghandle, LLOG_F_IS_PLAIN, NULL);
 162                 if (!rc) {
 163                         list_add(&loghandle->u.phd.phd_entry,
 164                                  &cathandle->u.chd.chd_head);
 165                 }
 166         }
 167         if (!rc) {
 168                 loghandle->u.phd.phd_cat_handle = cathandle;
 169                 loghandle->u.phd.phd_cookie.lgc_lgl = cathandle->lgh_id;
 170                 loghandle->u.phd.phd_cookie.lgc_index =
 171                         loghandle->lgh_hdr->llh_cat_idx;
 172         }
 173
 174 out:
 175         *res = loghandle;
 176         RETURN(rc);
 177 }
 178
 179 int llog_cat_put(struct llog_handle *cathandle)
 180 {
 181         struct llog_handle *loghandle, *n;
 182         int rc;
 183         ENTRY;
 184
 185         list_for_each_entry_safe(loghandle, n, &cathandle->u.chd.chd_head,
 186                                  u.phd.phd_entry) {
 187                 int err = llog_close(loghandle);
 188                 if (err)
 189                         CERROR("error closing loghandle\n");
 190         }
 191         rc = llog_close(cathandle);
 192         RETURN(rc);
 193 }
 194 EXPORT_SYMBOL(llog_cat_put);
 195
 196 /* Return the currently active log handle.  If the current log handle doesn't
 197  * have enough space left for the current record, start a new one.
 198  *
 199  * If reclen is 0, we only want to know what the currently active log is,
 200  * otherwise we get a lock on this log so nobody can steal our space.
 201  *
 202  * Assumes caller has already pushed us into the kernel context and is locking.
 203  *
 204  * NOTE: loghandle is write-locked upon successful return
 205  */
 206 static struct llog_handle *llog_cat_current_log(struct llog_handle *cathandle,
 207                                                 int create)
 208 {
 209         struct llog_handle *loghandle = NULL;
 210         ENTRY;
 211
 212         down_read(&cathandle->lgh_lock);
 213         loghandle = cathandle->u.chd.chd_current_log;
 214         if (loghandle) {
 215                 struct llog_log_hdr *llh = loghandle->lgh_hdr;
 216                 down_write(&loghandle->lgh_lock);
 217                 if (loghandle->lgh_last_idx < LLOG_BITMAP_SIZE(llh) - 1) {
 218                         up_read(&cathandle->lgh_lock);
 219                         RETURN(loghandle);
 220                 } else {
 221                         up_write(&loghandle->lgh_lock);
 222                 }
 223         }
 224         if (!create) {
 225                 if (loghandle)
 226                         down_write(&loghandle->lgh_lock);
 227                 up_read(&cathandle->lgh_lock);
 228                 RETURN(loghandle);
 229         }
 230         up_read(&cathandle->lgh_lock);
 231
 232         /* time to create new log */
 233
 234         /* first, we have to make sure the state hasn't changed */
 235         down_write(&cathandle->lgh_lock);
 236         loghandle = cathandle->u.chd.chd_current_log;
 237         if (loghandle) {
 238                 struct llog_log_hdr *llh = loghandle->lgh_hdr;
 239                 down_write(&loghandle->lgh_lock);
 240                 if (loghandle->lgh_last_idx < LLOG_BITMAP_SIZE(llh) - 1) {
 241                         up_write(&cathandle->lgh_lock);
 242                         RETURN(loghandle);
 243                 } else {
 244                         up_write(&loghandle->lgh_lock);
 245                 }
 246         }
 247
 248         CDEBUG(D_INODE, "creating new log\n");
 249         loghandle = llog_cat_new_log(cathandle);
 250         if (!IS_ERR(loghandle))
 251                 down_write(&loghandle->lgh_lock);
 252         up_write(&cathandle->lgh_lock);
 253         RETURN(loghandle);
 254 }
 255
 256 /* Add a single record to the recovery log(s) using a catalog
 257  * Returns as llog_write_record
 258  *
 259  * Assumes caller has already pushed us into the kernel context.
 260  */
 261 int llog_cat_add_rec(struct llog_handle *cathandle, struct llog_rec_hdr *rec,
 262                      struct llog_cookie *reccookie, void *buf)
 263 {
 264         struct llog_handle *loghandle;
 265         int rc;
 266         ENTRY;
 267
 268         LASSERT(rec->lrh_len <= LLOG_CHUNK_SIZE);
 269         loghandle = llog_cat_current_log(cathandle, 1);
 270         if (IS_ERR(loghandle))
 271                 RETURN(PTR_ERR(loghandle));
 272         /* loghandle is already locked by llog_cat_current_log() for us */
 273         rc = llog_write_rec(loghandle, rec, reccookie, 1, buf, -1);
 274         up_write(&loghandle->lgh_lock);
 275         if (rc == -ENOSPC) {
 276                 /* to create a new plain log */
 277                 loghandle = llog_cat_current_log(cathandle, 1);
 278                 if (IS_ERR(loghandle))
 279                         RETURN(PTR_ERR(loghandle));
 280                 rc = llog_write_rec(loghandle, rec, reccookie, 1, buf, -1);
 281                 up_write(&loghandle->lgh_lock);
 282         }
 283
 284         RETURN(rc);
 285 }
 286 EXPORT_SYMBOL(llog_cat_add_rec);
 287
 288 /* For each cookie in the cookie array, we clear the log in-use bit and either:
 289  * - the log is empty, so mark it free in the catalog header and delete it
 290  * - the log is not empty, just write out the log header
 291  *
 292  * The cookies may be in different log files, so we need to get new logs
 293  * each time.
 294  *
 295  * Assumes caller has already pushed us into the kernel context.
 296  */
 297 int llog_cat_cancel_records(struct llog_handle *cathandle, int count,
 298                         struct llog_cookie *cookies)
 299 {
 300         int i, index, rc = 0;
 301         ENTRY;
 302
 303         down_write(&cathandle->lgh_lock);
 304         for (i = 0; i < count; i++, cookies++) {
 305                 struct llog_handle *loghandle;
 306                 struct llog_logid *lgl = &cookies->lgc_lgl;
 307
 308                 rc = llog_cat_id2handle(cathandle, &loghandle, lgl);
 309                 if (rc) {
 310                         CERROR("Cannot find log "LPX64"\n", lgl->lgl_oid);
 311                         break;
 312                 }
 313
 314                 down_write(&loghandle->lgh_lock);
 315                 rc = llog_cancel_rec(loghandle, cookies->lgc_index);
 316                 up_write(&loghandle->lgh_lock);
 317
 318                 if (rc == 1) {          /* log has been destroyed */
 319                         index = loghandle->u.phd.phd_cookie.lgc_index;
 320                         if (cathandle->u.chd.chd_current_log == loghandle)
 321                                 cathandle->u.chd.chd_current_log = NULL;
 322                         llog_free_handle(loghandle);
 323
 324                         LASSERT(index);
 325                         llog_cat_set_first_idx(cathandle, index);
 326                         rc = llog_cancel_rec(cathandle, index);
 327                         if (rc == 0)
 328                                 CDEBUG(D_RPCTRACE,"cancel plain log at index %u"
 329                                        " of catalog "LPX64"\n",
 330                                        index, cathandle->lgh_id.lgl_oid);
 331                 }
 332         }
 333         up_write(&cathandle->lgh_lock);
 334
 335         RETURN(rc);
 336 }
 337 EXPORT_SYMBOL(llog_cat_cancel_records);
 338
 339 int llog_cat_process_cb(struct llog_handle *cat_llh, struct llog_rec_hdr *rec,
 340                         void *data)
 341 {
 342         struct llog_process_data *d = data;
 343         struct llog_logid_rec *lir = (struct llog_logid_rec *)rec;
 344         struct llog_handle *llh;
 345         int rc;
 346
 347         ENTRY;
 348         if (rec->lrh_type != LLOG_LOGID_MAGIC) {
 349                 CERROR("invalid record in catalog\n");
 350                 RETURN(-EINVAL);
 351         }
 352         CDEBUG(D_HA, "processing log "LPX64":%x at index %u of catalog "
 353                LPX64"\n", lir->lid_id.lgl_oid, lir->lid_id.lgl_ogen,
 354                rec->lrh_index, cat_llh->lgh_id.lgl_oid);
 355
 356         rc = llog_cat_id2handle(cat_llh, &llh, &lir->lid_id);
 357         if (rc) {
 358                 CERROR("Cannot find handle for log "LPX64"\n",
 359                        lir->lid_id.lgl_oid);
 360                 RETURN(rc);
 361         }
 362
 363         rc = llog_process(llh, d->lpd_cb, d->lpd_data, NULL);
 364         RETURN(rc);
 365 }
 366
 367 int llog_cat_process(struct llog_handle *cat_llh, llog_cb_t cb, void *data)
 368 {
 369         struct llog_process_data d;
 370         struct llog_process_cat_data cd;
 371         struct llog_log_hdr *llh = cat_llh->lgh_hdr;
 372         int rc;
 373         ENTRY;
 374
 375         LASSERT(llh->llh_flags & LLOG_F_IS_CAT);
 376         d.lpd_data = data;
 377         d.lpd_cb = cb;
 378
 379         if (llh->llh_cat_idx > cat_llh->lgh_last_idx) {
 380                 CWARN("catlog "LPX64" crosses index zero\n",
 381                       cat_llh->lgh_id.lgl_oid);
 382
 383                 cd.first_idx = llh->llh_cat_idx;
 384                 cd.last_idx = 0;
 385                 rc = llog_process(cat_llh, llog_cat_process_cb, &d, &cd);
 386                 if (rc != 0)
 387                         RETURN(rc);
 388
 389                 cd.first_idx = 0;
 390                 cd.last_idx = cat_llh->lgh_last_idx;
 391                 rc = llog_process(cat_llh, llog_cat_process_cb, &d, &cd);
 392         } else {
 393                 rc = llog_process(cat_llh, llog_cat_process_cb, &d, NULL);
 394         }
 395
 396         RETURN(rc);
 397 }
 398 EXPORT_SYMBOL(llog_cat_process);
 399
 400 static int llog_cat_reverse_process_cb(struct llog_handle *cat_llh,
 401                                        struct llog_rec_hdr *rec, void *data)
 402 {
 403         struct llog_process_data *d = data;
 404         struct llog_logid_rec *lir = (struct llog_logid_rec *)rec;
 405         struct llog_handle *llh;
 406         int rc;
 407
 408         if (le32_to_cpu(rec->lrh_type) != LLOG_LOGID_MAGIC) {
 409                 CERROR("invalid record in catalog\n");
 410                 RETURN(-EINVAL);
 411         }
 412         CDEBUG(D_HA, "processing log "LPX64":%x at index %u of catalog "
 413                LPX64"\n", lir->lid_id.lgl_oid, lir->lid_id.lgl_ogen,
 414                le32_to_cpu(rec->lrh_index), cat_llh->lgh_id.lgl_oid);
 415
 416         rc = llog_cat_id2handle(cat_llh, &llh, &lir->lid_id);
 417         if (rc) {
 418                 CERROR("Cannot find handle for log "LPX64"\n",
 419                        lir->lid_id.lgl_oid);
 420                 RETURN(rc);
 421         }
 422
 423         rc = llog_reverse_process(llh, d->lpd_cb, d->lpd_data, NULL);
 424         RETURN(rc);
 425 }
 426
 427 int llog_cat_reverse_process(struct llog_handle *cat_llh,
 428                              llog_cb_t cb, void *data)
 429 {
 430         struct llog_process_data d;
 431         struct llog_process_cat_data cd;
 432         struct llog_log_hdr *llh = cat_llh->lgh_hdr;
 433         int rc;
 434         ENTRY;
 435
 436         LASSERT(llh->llh_flags & LLOG_F_IS_CAT);
 437         d.lpd_data = data;
 438         d.lpd_cb = cb;
 439
 440         if (llh->llh_cat_idx > cat_llh->lgh_last_idx) {
 441                 CWARN("catalog "LPX64" crosses index zero\n",
 442                       cat_llh->lgh_id.lgl_oid);
 443
 444                 cd.first_idx = 0;
 445                 cd.last_idx = cat_llh->lgh_last_idx;
 446                 rc = llog_reverse_process(cat_llh, llog_cat_reverse_process_cb,
 447                                           &d, &cd);
 448                 if (rc != 0)
 449                         RETURN(rc);
 450
 451                 cd.first_idx = le32_to_cpu(llh->llh_cat_idx);
 452                 cd.last_idx = 0;
 453                 rc = llog_reverse_process(cat_llh, llog_cat_reverse_process_cb,
 454                                           &d, &cd);
 455         } else {
 456                 rc = llog_reverse_process(cat_llh, llog_cat_reverse_process_cb,
 457                                           &d, NULL);
 458         }
 459
 460         RETURN(rc);
 461 }
 462 EXPORT_SYMBOL(llog_cat_reverse_process);
 463
 464 int llog_cat_set_first_idx(struct llog_handle *cathandle, int index)
 465 {
 466         struct llog_log_hdr *llh = cathandle->lgh_hdr;
 467         int i, bitmap_size, idx;
 468         ENTRY;
 469
 470         bitmap_size = LLOG_BITMAP_SIZE(llh);
 471         if (llh->llh_cat_idx == (index - 1)) {
 472                 idx = llh->llh_cat_idx + 1;
 473                 llh->llh_cat_idx = idx;
 474                 if (idx == cathandle->lgh_last_idx)
 475                         goto out;
 476                 for (i = (index + 1) % bitmap_size;
 477                      i != cathandle->lgh_last_idx;
 478                      i = (i + 1) % bitmap_size) {
 479                         if (!ext2_test_bit(i, llh->llh_bitmap)) {
 480                                 idx = llh->llh_cat_idx + 1;
 481                                 llh->llh_cat_idx = idx;
 482                         } else if (i == 0) {
 483                                 llh->llh_cat_idx = 0;
 484                         } else {
 485                                 break;
 486                         }
 487                 }
 488 out:
 489                 CDEBUG(D_RPCTRACE, "set catlog "LPX64" first idx %u\n",
 490                        cathandle->lgh_id.lgl_oid, llh->llh_cat_idx);
 491         }
 492
 493         RETURN(0);
 494 }
 495
 496 #if 0
 497 /* Assumes caller has already pushed us into the kernel context. */
 498 int llog_cat_init(struct llog_handle *cathandle, struct obd_uuid *tgtuuid)
 499 {
 500         struct llog_log_hdr *llh;
 501         loff_t offset = 0;
 502         int rc = 0;
 503         ENTRY;
 504
 505         LASSERT(sizeof(*llh) == LLOG_CHUNK_SIZE);
 506
 507         down(&cathandle->lgh_lock);
 508         llh = cathandle->lgh_hdr;
 509
 510         if (i_size_read(cathandle->lgh_file->f_dentry->d_inode) == 0) {
 511                 llog_write_rec(cathandle, &llh->llh_hdr, NULL, 0, NULL, 0);
 512
 513 write_hdr:
 514                 rc = lustre_fwrite(cathandle->lgh_file, llh, LLOG_CHUNK_SIZE,
 515                                    &offset);
 516                 if (rc != LLOG_CHUNK_SIZE) {
 517                         CERROR("error writing catalog header: rc %d\n", rc);
 518                         OBD_FREE(llh, sizeof(*llh));
 519                         if (rc >= 0)
 520                                 rc = -ENOSPC;
 521                 } else
 522                         rc = 0;
 523         } else {
 524                 rc = lustre_fread(cathandle->lgh_file, llh, LLOG_CHUNK_SIZE,
 525                                   &offset);
 526                 if (rc != LLOG_CHUNK_SIZE) {
 527                         CERROR("error reading catalog header: rc %d\n", rc);
 528                         /* Can we do much else if the header is bad? */
 529                         goto write_hdr;
 530                 } else
 531                         rc = 0;
 532         }
 533
 534         cathandle->lgh_tgtuuid = &llh->llh_tgtuuid;
 535         up(&cathandle->lgh_lock);
 536         RETURN(rc);
 537 }
 538 EXPORT_SYMBOL(llog_cat_init);
 539
 540 #endif