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         } else {
  69                 if (index == 0)
  70                         index = 1;
  71                 if (ext2_set_bit(index, llh->llh_bitmap)) {
  72                         CERROR("argh, index %u already set in log bitmap?\n",
  73                                index);
  74                         LBUG(); /* should never happen */
  75                 }
  76                 cathandle->lgh_last_idx = index;
  77                 llh->llh_count++;
  78                 llh->llh_tail.lrt_index = index;
  79         }
  80
  81         rc = llog_create(cathandle->lgh_ctxt, &loghandle, NULL, NULL);
  82         if (rc)
  83                 RETURN(ERR_PTR(rc));
  84
  85         rc = llog_init_handle(loghandle,
  86                               LLOG_F_IS_PLAIN | LLOG_F_ZAP_WHEN_EMPTY,
  87                               &cathandle->lgh_hdr->llh_tgtuuid);
  88         if (rc)
  89                 GOTO(out_destroy, rc);
  90
  91         CDEBUG(D_HA, "new recovery log "LPX64":%x for index %u of catalog "
  92                LPX64"\n", loghandle->lgh_id.lgl_oid, loghandle->lgh_id.lgl_ogen,
  93                index, cathandle->lgh_id.lgl_oid);
  94         /* build the record for this log in the catalog */
  95         rec.lid_hdr.lrh_len = sizeof(rec);
  96         rec.lid_hdr.lrh_index = index;
  97         rec.lid_hdr.lrh_type = LLOG_LOGID_MAGIC;
  98         rec.lid_id = loghandle->lgh_id;
  99         rec.lid_tail.lrt_len = sizeof(rec);
 100         rec.lid_tail.lrt_index = index;
 101
 102         /* update the catalog: header and record */
 103         rc = llog_write_rec(cathandle, &rec.lid_hdr,
 104                             &loghandle->u.phd.phd_cookie, 1, NULL, index);
 105         if (rc < 0) {
 106                 GOTO(out_destroy, rc);
 107         }
 108
 109         loghandle->lgh_hdr->llh_cat_idx = index;
 110         cathandle->u.chd.chd_current_log = loghandle;
 111         LASSERT(list_empty(&loghandle->u.phd.phd_entry));
 112         list_add_tail(&loghandle->u.phd.phd_entry, &cathandle->u.chd.chd_head);
 113
 114  out_destroy:
 115         if (rc < 0)
 116                 llog_destroy(loghandle);
 117
 118         RETURN(loghandle);
 119 }
 120 EXPORT_SYMBOL(llog_cat_new_log);
 121
 122 /* Open an existent log handle and add it to the open list.
 123  * This log handle will be closed when all of the records in it are removed.
 124  *
 125  * Assumes caller has already pushed us into the kernel context and is locking.
 126  * We return a lock on the handle to ensure nobody yanks it from us.
 127  */
 128 int llog_cat_id2handle(struct llog_handle *cathandle, struct llog_handle **res,
 129                        struct llog_logid *logid)
 130 {
 131         struct llog_handle *loghandle;
 132         int rc = 0;
 133         ENTRY;
 134
 135         if (cathandle == NULL)
 136                 RETURN(-EBADF);
 137
 138         list_for_each_entry(loghandle, &cathandle->u.chd.chd_head,
 139                             u.phd.phd_entry) {
 140                 struct llog_logid *cgl = &loghandle->lgh_id;
 141                 if (cgl->lgl_oid == logid->lgl_oid) {
 142                         if (cgl->lgl_ogen != logid->lgl_ogen) {
 143                                 CERROR("log "LPX64" generation %x != %x\n",
 144                                        logid->lgl_oid, cgl->lgl_ogen,
 145                                        logid->lgl_ogen);
 146                                 continue;
 147                         }
 148                         loghandle->u.phd.phd_cat_handle = cathandle;
 149                         GOTO(out, rc = 0);
 150                 }
 151         }
 152
 153         rc = llog_create(cathandle->lgh_ctxt, &loghandle, logid, NULL);
 154         if (rc) {
 155                 CERROR("error opening log id "LPX64":%x: rc %d\n",
 156                        logid->lgl_oid, logid->lgl_ogen, rc);
 157         } else {
 158                 rc = llog_init_handle(loghandle, LLOG_F_IS_PLAIN, NULL);
 159                 if (!rc) {
 160                         list_add(&loghandle->u.phd.phd_entry,
 161                                  &cathandle->u.chd.chd_head);
 162                 }
 163         }
 164         if (!rc) {
 165                 loghandle->u.phd.phd_cat_handle = cathandle;
 166                 loghandle->u.phd.phd_cookie.lgc_lgl = cathandle->lgh_id;
 167                 loghandle->u.phd.phd_cookie.lgc_index =
 168                         loghandle->lgh_hdr->llh_cat_idx;
 169         }
 170
 171 out:
 172         *res = loghandle;
 173         RETURN(rc);
 174 }
 175
 176 int llog_cat_put(struct llog_handle *cathandle)
 177 {
 178         struct llog_handle *loghandle, *n;
 179         int rc;
 180         ENTRY;
 181
 182         list_for_each_entry_safe(loghandle, n, &cathandle->u.chd.chd_head,
 183                                  u.phd.phd_entry) {
 184                 int err = llog_close(loghandle);
 185                 if (err)
 186                         CERROR("error closing loghandle\n");
 187         }
 188         rc = llog_close(cathandle);
 189         RETURN(rc);
 190 }
 191 EXPORT_SYMBOL(llog_cat_put);
 192
 193 /* Return the currently active log handle.  If the current log handle doesn't
 194  * have enough space left for the current record, start a new one.
 195  *
 196  * If reclen is 0, we only want to know what the currently active log is,
 197  * otherwise we get a lock on this log so nobody can steal our space.
 198  *
 199  * Assumes caller has already pushed us into the kernel context and is locking.
 200  *
 201  * NOTE: loghandle is write-locked upon successful return
 202  */
 203 static struct llog_handle *llog_cat_current_log(struct llog_handle *cathandle,
 204                                                 int create)
 205 {
 206         struct llog_handle *loghandle = NULL;
 207         ENTRY;
 208
 209         down_read(&cathandle->lgh_lock);
 210         loghandle = cathandle->u.chd.chd_current_log;
 211         if (loghandle) {
 212                 struct llog_log_hdr *llh = loghandle->lgh_hdr;
 213                 down_write(&loghandle->lgh_lock);
 214                 if (loghandle->lgh_last_idx < LLOG_BITMAP_SIZE(llh) - 1) {
 215                         up_read(&cathandle->lgh_lock);
 216                         RETURN(loghandle);
 217                 } else {
 218                         up_write(&loghandle->lgh_lock);
 219                 }
 220         }
 221         if (!create) {
 222                 if (loghandle)
 223                         down_write(&loghandle->lgh_lock);
 224                 up_read(&cathandle->lgh_lock);
 225                 RETURN(loghandle);
 226         }
 227         up_read(&cathandle->lgh_lock);
 228
 229         /* time to create new log */
 230
 231         /* first, we have to make sure the state hasn't changed */
 232         down_write(&cathandle->lgh_lock);
 233         loghandle = cathandle->u.chd.chd_current_log;
 234         if (loghandle) {
 235                 struct llog_log_hdr *llh = loghandle->lgh_hdr;
 236                 down_write(&loghandle->lgh_lock);
 237                 if (loghandle->lgh_last_idx < LLOG_BITMAP_SIZE(llh) - 1) {
 238                         up_write(&cathandle->lgh_lock);
 239                         RETURN(loghandle);
 240                 } else {
 241                         up_write(&loghandle->lgh_lock);
 242                 }
 243         }
 244
 245         CDEBUG(D_INODE, "creating new log\n");
 246         loghandle = llog_cat_new_log(cathandle);
 247         if (!IS_ERR(loghandle))
 248                 down_write(&loghandle->lgh_lock);
 249         up_write(&cathandle->lgh_lock);
 250         RETURN(loghandle);
 251 }
 252
 253 /* Add a single record to the recovery log(s) using a catalog
 254  * Returns as llog_write_record
 255  *
 256  * Assumes caller has already pushed us into the kernel context.
 257  */
 258 int llog_cat_add_rec(struct llog_handle *cathandle, struct llog_rec_hdr *rec,
 259                      struct llog_cookie *reccookie, void *buf)
 260 {
 261         struct llog_handle *loghandle;
 262         int rc;
 263         ENTRY;
 264
 265         LASSERT(rec->lrh_len <= LLOG_CHUNK_SIZE);
 266         loghandle = llog_cat_current_log(cathandle, 1);
 267         if (IS_ERR(loghandle))
 268                 RETURN(PTR_ERR(loghandle));
 269         /* loghandle is already locked by llog_cat_current_log() for us */
 270         rc = llog_write_rec(loghandle, rec, reccookie, 1, buf, -1);
 271         up_write(&loghandle->lgh_lock);
 272         if (rc == -ENOSPC) {
 273                 /* to create a new plain log */
 274                 loghandle = llog_cat_current_log(cathandle, 1);
 275                 if (IS_ERR(loghandle))
 276                         RETURN(PTR_ERR(loghandle));
 277                 rc = llog_write_rec(loghandle, rec, reccookie, 1, buf, -1);
 278                 up_write(&loghandle->lgh_lock);
 279         }
 280
 281         RETURN(rc);
 282 }
 283 EXPORT_SYMBOL(llog_cat_add_rec);
 284
 285 /* For each cookie in the cookie array, we clear the log in-use bit and either:
 286  * - the log is empty, so mark it free in the catalog header and delete it
 287  * - the log is not empty, just write out the log header
 288  *
 289  * The cookies may be in different log files, so we need to get new logs
 290  * each time.
 291  *
 292  * Assumes caller has already pushed us into the kernel context.
 293  */
 294 int llog_cat_cancel_records(struct llog_handle *cathandle, int count,
 295                         struct llog_cookie *cookies)
 296 {
 297         int i, index, rc = 0;
 298         ENTRY;
 299
 300         down_write(&cathandle->lgh_lock);
 301         for (i = 0; i < count; i++, cookies++) {
 302                 struct llog_handle *loghandle;
 303                 struct llog_logid *lgl = &cookies->lgc_lgl;
 304
 305                 rc = llog_cat_id2handle(cathandle, &loghandle, lgl);
 306                 if (rc) {
 307                         CERROR("Cannot find log "LPX64"\n", lgl->lgl_oid);
 308                         break;
 309                 }
 310
 311                 down_write(&loghandle->lgh_lock);
 312                 rc = llog_cancel_rec(loghandle, cookies->lgc_index);
 313                 up_write(&loghandle->lgh_lock);
 314
 315                 if (rc == 1) {          /* log has been destroyed */
 316                         index = loghandle->u.phd.phd_cookie.lgc_index;
 317                         if (cathandle->u.chd.chd_current_log == loghandle)
 318                                 cathandle->u.chd.chd_current_log = NULL;
 319                         llog_free_handle(loghandle);
 320
 321                         LASSERT(index);
 322                         llog_cat_set_first_idx(cathandle, index);
 323                         rc = llog_cancel_rec(cathandle, index);
 324                         if (rc == 0)
 325                                 CDEBUG(D_HA, "cancel plain log at index %u "
 326                                        "of catalog "LPX64"\n",
 327                                        index, cathandle->lgh_id.lgl_oid);
 328                 }
 329         }
 330         up_write(&cathandle->lgh_lock);
 331
 332         RETURN(rc);
 333 }
 334 EXPORT_SYMBOL(llog_cat_cancel_records);
 335
 336 int llog_cat_process_cb(struct llog_handle *cat_llh, struct llog_rec_hdr *rec,
 337                         void *data)
 338 {
 339         struct llog_process_data *d = data;
 340         struct llog_logid_rec *lir = (struct llog_logid_rec *)rec;
 341         struct llog_handle *llh;
 342         int rc;
 343
 344         ENTRY;
 345         if (rec->lrh_type != LLOG_LOGID_MAGIC) {
 346                 CERROR("invalid record in catalog\n");
 347                 RETURN(-EINVAL);
 348         }
 349         CDEBUG(D_HA, "processing log "LPX64":%x at index %u of catalog "
 350                LPX64"\n", lir->lid_id.lgl_oid, lir->lid_id.lgl_ogen,
 351                rec->lrh_index, cat_llh->lgh_id.lgl_oid);
 352
 353         rc = llog_cat_id2handle(cat_llh, &llh, &lir->lid_id);
 354         if (rc) {
 355                 CERROR("Cannot find handle for log "LPX64"\n",
 356                        lir->lid_id.lgl_oid);
 357                 RETURN(rc);
 358         }
 359
 360         rc = llog_process(llh, d->lpd_cb, d->lpd_data, NULL);
 361         RETURN(rc);
 362 }
 363
 364 int llog_cat_process(struct llog_handle *cat_llh, llog_cb_t cb, void *data)
 365 {
 366         struct llog_process_data d;
 367         struct llog_process_cat_data cd;
 368         struct llog_log_hdr *llh = cat_llh->lgh_hdr;
 369         int rc;
 370         ENTRY;
 371
 372         LASSERT(llh->llh_flags & LLOG_F_IS_CAT);
 373         d.lpd_data = data;
 374         d.lpd_cb = cb;
 375
 376         if (llh->llh_cat_idx > cat_llh->lgh_last_idx) {
 377                 CWARN("catlog "LPX64" crosses index zero\n",
 378                       cat_llh->lgh_id.lgl_oid);
 379
 380                 cd.first_idx = llh->llh_cat_idx;
 381                 cd.last_idx = 0;
 382                 rc = llog_process(cat_llh, llog_cat_process_cb, &d, &cd);
 383                 if (rc != 0)
 384                         RETURN(rc);
 385
 386                 cd.first_idx = 0;
 387                 cd.last_idx = cat_llh->lgh_last_idx;
 388                 rc = llog_process(cat_llh, llog_cat_process_cb, &d, &cd);
 389         } else {
 390                 rc = llog_process(cat_llh, llog_cat_process_cb, &d, NULL);
 391         }
 392
 393         RETURN(rc);
 394 }
 395 EXPORT_SYMBOL(llog_cat_process);
 396
 397 static int llog_cat_reverse_process_cb(struct llog_handle *cat_llh,
 398                                        struct llog_rec_hdr *rec, void *data)
 399 {
 400         struct llog_process_data *d = data;
 401         struct llog_logid_rec *lir = (struct llog_logid_rec *)rec;
 402         struct llog_handle *llh;
 403         int rc;
 404
 405         if (le32_to_cpu(rec->lrh_type) != LLOG_LOGID_MAGIC) {
 406                 CERROR("invalid record in catalog\n");
 407                 RETURN(-EINVAL);
 408         }
 409         CDEBUG(D_HA, "processing log "LPX64":%x at index %u of catalog "
 410                LPX64"\n", lir->lid_id.lgl_oid, lir->lid_id.lgl_ogen,
 411                le32_to_cpu(rec->lrh_index), cat_llh->lgh_id.lgl_oid);
 412
 413         rc = llog_cat_id2handle(cat_llh, &llh, &lir->lid_id);
 414         if (rc) {
 415                 CERROR("Cannot find handle for log "LPX64"\n",
 416                        lir->lid_id.lgl_oid);
 417                 RETURN(rc);
 418         }
 419
 420         rc = llog_reverse_process(llh, d->lpd_cb, d->lpd_data, NULL);
 421         RETURN(rc);
 422 }
 423
 424 int llog_cat_reverse_process(struct llog_handle *cat_llh,
 425                              llog_cb_t cb, void *data)
 426 {
 427         struct llog_process_data d;
 428         struct llog_process_cat_data cd;
 429         struct llog_log_hdr *llh = cat_llh->lgh_hdr;
 430         int rc;
 431         ENTRY;
 432
 433         LASSERT(llh->llh_flags & LLOG_F_IS_CAT);
 434         d.lpd_data = data;
 435         d.lpd_cb = cb;
 436
 437         if (llh->llh_cat_idx > cat_llh->lgh_last_idx) {
 438                 CWARN("catalog "LPX64" crosses index zero\n",
 439                       cat_llh->lgh_id.lgl_oid);
 440
 441                 cd.first_idx = 0;
 442                 cd.last_idx = cat_llh->lgh_last_idx;
 443                 rc = llog_reverse_process(cat_llh, llog_cat_reverse_process_cb,
 444                                           &d, &cd);
 445                 if (rc != 0)
 446                         RETURN(rc);
 447
 448                 cd.first_idx = le32_to_cpu(llh->llh_cat_idx);
 449                 cd.last_idx = 0;
 450                 rc = llog_reverse_process(cat_llh, llog_cat_reverse_process_cb,
 451                                           &d, &cd);
 452         } else {
 453                 rc = llog_reverse_process(cat_llh, llog_cat_reverse_process_cb,
 454                                           &d, NULL);
 455         }
 456
 457         RETURN(rc);
 458 }
 459 EXPORT_SYMBOL(llog_cat_reverse_process);
 460
 461 int llog_cat_set_first_idx(struct llog_handle *cathandle, int index)
 462 {
 463         struct llog_log_hdr *llh = cathandle->lgh_hdr;
 464         int i, bitmap_size, idx;
 465         ENTRY;
 466
 467         bitmap_size = LLOG_BITMAP_SIZE(llh);
 468         if (llh->llh_cat_idx == (index - 1)) {
 469                 idx = llh->llh_cat_idx + 1;
 470                 llh->llh_cat_idx = idx;
 471                 if (idx == cathandle->lgh_last_idx)
 472                         goto out;
 473                 for (i = (index + 1) % bitmap_size;
 474                      i != cathandle->lgh_last_idx;
 475                      i = (i + 1) % bitmap_size) {
 476                         if (!ext2_test_bit(i, llh->llh_bitmap)) {
 477                                 idx = llh->llh_cat_idx + 1;
 478                                 llh->llh_cat_idx = idx;
 479                         } else if (i == 0) {
 480                                 llh->llh_cat_idx = 0;
 481                         } else {
 482                                 break;
 483                         }
 484                 }
 485 out:
 486                 CDEBUG(D_HA, "set catlog "LPX64" first idx %u\n",
 487                        cathandle->lgh_id.lgl_oid, llh->llh_cat_idx);
 488         }
 489
 490         RETURN(0);
 491 }
 492
 493 #if 0
 494 /* Assumes caller has already pushed us into the kernel context. */
 495 int llog_cat_init(struct llog_handle *cathandle, struct obd_uuid *tgtuuid)
 496 {
 497         struct llog_log_hdr *llh;
 498         loff_t offset = 0;
 499         int rc = 0;
 500         ENTRY;
 501
 502         LASSERT(sizeof(*llh) == LLOG_CHUNK_SIZE);
 503
 504         down(&cathandle->lgh_lock);
 505         llh = cathandle->lgh_hdr;
 506
 507         if (cathandle->lgh_file->f_dentry->d_inode->i_size == 0) {
 508                 llog_write_rec(cathandle, &llh->llh_hdr, NULL, 0, NULL, 0);
 509
 510 write_hdr:
 511                 rc = lustre_fwrite(cathandle->lgh_file, llh, LLOG_CHUNK_SIZE,
 512                                    &offset);
 513                 if (rc != LLOG_CHUNK_SIZE) {
 514                         CERROR("error writing catalog header: rc %d\n", rc);
 515                         OBD_FREE(llh, sizeof(*llh));
 516                         if (rc >= 0)
 517                                 rc = -ENOSPC;
 518                 } else
 519                         rc = 0;
 520         } else {
 521                 rc = lustre_fread(cathandle->lgh_file, llh, LLOG_CHUNK_SIZE,
 522                                   &offset);
 523                 if (rc != LLOG_CHUNK_SIZE) {
 524                         CERROR("error reading catalog header: rc %d\n", rc);
 525                         /* Can we do much else if the header is bad? */
 526                         goto write_hdr;
 527                 } else
 528                         rc = 0;
 529         }
 530
 531         cathandle->lgh_tgtuuid = &llh->llh_tgtuuid;
 532         up(&cathandle->lgh_lock);
 533         RETURN(rc);
 534 }
 535 EXPORT_SYMBOL(llog_cat_init);
 536
 537 #endif