lustre/obdclass/llog.c

   1 /* -*- mode: c; c-basic-offset: 8; indent-tabs-mode: nil; -*-
   2  * vim:expandtab:shiftwidth=8:tabstop=8:
   3  *
   4  * GPL HEADER START
   5  *
   6  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
   7  *
   8  * This program is free software; you can redistribute it and/or modify
   9  * it under the terms of the GNU General Public License version 2 only,
  10  * as published by the Free Software Foundation.
  11  *
  12  * This program is distributed in the hope that it will be useful, but
  13  * WITHOUT ANY WARRANTY; without even the implied warranty of
  14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  15  * General Public License version 2 for more details (a copy is included
  16  * in the LICENSE file that accompanied this code).
  17  *
  18  * You should have received a copy of the GNU General Public License
  19  * version 2 along with this program; If not, see
  20  * http://www.sun.com/software/products/lustre/docs/GPLv2.pdf
  21  *
  22  * Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
  23  * CA 95054 USA or visit www.sun.com if you need additional information or
  24  * have any questions.
  25  *
  26  * GPL HEADER END
  27  */
  28 /*
  29  * Copyright (c) 2003, 2010, Oracle and/or its affiliates. All rights reserved.
  30  * Use is subject to license terms.
  31  */
  32 /*
  33  * This file is part of Lustre, http://www.lustre.org/
  34  * Lustre is a trademark of Sun Microsystems, Inc.
  35  *
  36  * lustre/obdclass/llog.c
  37  *
  38  * OST<->MDS recovery logging infrastructure.
  39  * Invariants in implementation:
  40  * - we do not share logs among different OST<->MDS connections, so that
  41  *   if an OST or MDS fails it need only look at log(s) relevant to itself
  42  *
  43  * Author: Andreas Dilger <adilger@clusterfs.com>
  44  */
  45
  46 #define DEBUG_SUBSYSTEM S_LOG
  47
  48 #ifndef EXPORT_SYMTAB
  49 #define EXPORT_SYMTAB
  50 #endif
  51
  52 #ifndef __KERNEL__
  53 #include <liblustre.h>
  54 #endif
  55
  56 #include <obd_class.h>
  57 #include <lustre_log.h>
  58 #include <libcfs/list.h>
  59 #include "llog_internal.h"
  60
  61 /* Allocate a new log or catalog handle */
  62 struct llog_handle *llog_alloc_handle(void)
  63 {
  64         struct llog_handle *loghandle;
  65         ENTRY;
  66
  67         OBD_ALLOC(loghandle, sizeof(*loghandle));
  68         if (loghandle == NULL)
  69                 RETURN(ERR_PTR(-ENOMEM));
  70
  71         cfs_init_rwsem(&loghandle->lgh_lock);
  72
  73         RETURN(loghandle);
  74 }
  75 EXPORT_SYMBOL(llog_alloc_handle);
  76
  77
  78 void llog_free_handle(struct llog_handle *loghandle)
  79 {
  80         if (!loghandle)
  81                 return;
  82
  83         if (!loghandle->lgh_hdr)
  84                 goto out;
  85         if (loghandle->lgh_hdr->llh_flags & LLOG_F_IS_PLAIN)
  86                 cfs_list_del_init(&loghandle->u.phd.phd_entry);
  87         if (loghandle->lgh_hdr->llh_flags & LLOG_F_IS_CAT)
  88                 LASSERT(cfs_list_empty(&loghandle->u.chd.chd_head));
  89         OBD_FREE(loghandle->lgh_hdr, LLOG_CHUNK_SIZE);
  90
  91  out:
  92         OBD_FREE(loghandle, sizeof(*loghandle));
  93 }
  94 EXPORT_SYMBOL(llog_free_handle);
  95
  96 /* returns negative on error; 0 if success; 1 if success & log destroyed */
  97 int llog_cancel_rec(struct llog_handle *loghandle, int index)
  98 {
  99         struct llog_log_hdr *llh = loghandle->lgh_hdr;
 100         int rc = 0;
 101         ENTRY;
 102
 103         CDEBUG(D_RPCTRACE, "Canceling %d in log "LPX64"\n",
 104                index, loghandle->lgh_id.lgl_oid);
 105
 106         if (index == 0) {
 107                 CERROR("Can't cancel index 0 which is header\n");
 108                 RETURN(-EINVAL);
 109         }
 110
 111         if (!ext2_clear_bit(index, llh->llh_bitmap)) {
 112                 CDEBUG(D_RPCTRACE, "Catalog index %u already clear?\n", index);
 113                 RETURN(-ENOENT);
 114         }
 115
 116         llh->llh_count--;
 117
 118         if ((llh->llh_flags & LLOG_F_ZAP_WHEN_EMPTY) &&
 119             (llh->llh_count == 1) &&
 120             (loghandle->lgh_last_idx == (LLOG_BITMAP_BYTES * 8) - 1)) {
 121                 rc = llog_destroy(loghandle);
 122                 if (rc) {
 123                         CERROR("Failure destroying log after last cancel: %d\n",
 124                                rc);
 125                         ext2_set_bit(index, llh->llh_bitmap);
 126                         llh->llh_count++;
 127                 } else {
 128                         rc = 1;
 129                 }
 130                 RETURN(rc);
 131         }
 132
 133         rc = llog_write_rec(loghandle, &llh->llh_hdr, NULL, 0, NULL, 0);
 134         if (rc) {
 135                 CERROR("Failure re-writing header %d\n", rc);
 136                 ext2_set_bit(index, llh->llh_bitmap);
 137                 llh->llh_count++;
 138         }
 139         RETURN(rc);
 140 }
 141 EXPORT_SYMBOL(llog_cancel_rec);
 142
 143 int llog_init_handle(struct llog_handle *handle, int flags,
 144                      struct obd_uuid *uuid)
 145 {
 146         int rc;
 147         struct llog_log_hdr *llh;
 148         ENTRY;
 149         LASSERT(handle->lgh_hdr == NULL);
 150
 151         OBD_ALLOC(llh, sizeof(*llh));
 152         if (llh == NULL)
 153                 RETURN(-ENOMEM);
 154         handle->lgh_hdr = llh;
 155         /* first assign flags to use llog_client_ops */
 156         llh->llh_flags = flags;
 157         rc = llog_read_header(handle);
 158         if (rc == 0) {
 159                 flags = llh->llh_flags;
 160                 if (uuid && !obd_uuid_equals(uuid, &llh->llh_tgtuuid)) {
 161                         CERROR("uuid mismatch: %s/%s\n", (char *)uuid->uuid,
 162                                (char *)llh->llh_tgtuuid.uuid);
 163                         rc = -EEXIST;
 164                 }
 165                 GOTO(out, rc);
 166         } else if (rc != LLOG_EEMPTY || !flags) {
 167                 /* set a pesudo flag for initialization */
 168                 flags = LLOG_F_IS_CAT;
 169                 GOTO(out, rc);
 170         }
 171         rc = 0;
 172
 173         handle->lgh_last_idx = 0; /* header is record with index 0 */
 174         llh->llh_count = 1;         /* for the header record */
 175         llh->llh_hdr.lrh_type = LLOG_HDR_MAGIC;
 176         llh->llh_hdr.lrh_len = llh->llh_tail.lrt_len = LLOG_CHUNK_SIZE;
 177         llh->llh_hdr.lrh_index = llh->llh_tail.lrt_index = 0;
 178         llh->llh_timestamp = cfs_time_current_sec();
 179         if (uuid)
 180                 memcpy(&llh->llh_tgtuuid, uuid, sizeof(llh->llh_tgtuuid));
 181         llh->llh_bitmap_offset = offsetof(typeof(*llh),llh_bitmap);
 182         ext2_set_bit(0, llh->llh_bitmap);
 183
 184 out:
 185         if (flags & LLOG_F_IS_CAT) {
 186                 CFS_INIT_LIST_HEAD(&handle->u.chd.chd_head);
 187                 llh->llh_size = sizeof(struct llog_logid_rec);
 188         } else if (flags & LLOG_F_IS_PLAIN) {
 189                 CFS_INIT_LIST_HEAD(&handle->u.phd.phd_entry);
 190         } else {
 191                 CERROR("Unknown flags: %#x (Expected %#x or %#x\n",
 192                        flags, LLOG_F_IS_CAT, LLOG_F_IS_PLAIN);
 193                 LBUG();
 194         }
 195
 196         if (rc) {
 197                 OBD_FREE(llh, sizeof(*llh));
 198                 handle->lgh_hdr = NULL;
 199         }
 200         RETURN(rc);
 201 }
 202 EXPORT_SYMBOL(llog_init_handle);
 203
 204 int llog_close(struct llog_handle *loghandle)
 205 {
 206         struct llog_operations *lop;
 207         int rc;
 208         ENTRY;
 209
 210         rc = llog_handle2ops(loghandle, &lop);
 211         if (rc)
 212                 GOTO(out, rc);
 213         if (lop->lop_close == NULL)
 214                 GOTO(out, -EOPNOTSUPP);
 215         rc = lop->lop_close(loghandle);
 216  out:
 217         llog_free_handle(loghandle);
 218         RETURN(rc);
 219 }
 220 EXPORT_SYMBOL(llog_close);
 221
 222 static int llog_process_thread(void *arg)
 223 {
 224         struct llog_process_info     *lpi = (struct llog_process_info *)arg;
 225         struct llog_handle           *loghandle = lpi->lpi_loghandle;
 226         struct llog_log_hdr          *llh = loghandle->lgh_hdr;
 227         struct llog_process_cat_data *cd  = lpi->lpi_catdata;
 228         char                         *buf;
 229         __u64                         cur_offset = LLOG_CHUNK_SIZE;
 230         __u64                         last_offset;
 231         int                           rc = 0, index = 1, last_index;
 232         int                           saved_index = 0, last_called_index = 0;
 233
 234         LASSERT(llh);
 235
 236         OBD_ALLOC(buf, LLOG_CHUNK_SIZE);
 237         if (!buf) {
 238                 lpi->lpi_rc = -ENOMEM;
 239 #ifdef __KERNEL__
 240                 cfs_complete(&lpi->lpi_completion);
 241 #endif
 242                 return 0;
 243         }
 244
 245         if (!(lpi->lpi_flags & LLOG_FLAG_NODEAMON))
 246                 cfs_daemonize_ctxt("llog_process_thread");
 247
 248         if (cd != NULL) {
 249                 last_called_index = cd->lpcd_first_idx;
 250                 index = cd->lpcd_first_idx + 1;
 251         }
 252         if (cd != NULL && cd->lpcd_last_idx)
 253                 last_index = cd->lpcd_last_idx;
 254         else
 255                 last_index = LLOG_BITMAP_BYTES * 8 - 1;
 256
 257         while (rc == 0) {
 258                 struct llog_rec_hdr *rec;
 259
 260                 /* skip records not set in bitmap */
 261                 while (index <= last_index &&
 262                        !ext2_test_bit(index, llh->llh_bitmap))
 263                         ++index;
 264
 265                 LASSERT(index <= last_index + 1);
 266                 if (index == last_index + 1)
 267                         break;
 268
 269                 CDEBUG(D_OTHER, "index: %d last_index %d\n",
 270                        index, last_index);
 271
 272                 /* get the buf with our target record; avoid old garbage */
 273                 memset(buf, 0, LLOG_CHUNK_SIZE);
 274                 last_offset = cur_offset;
 275                 rc = llog_next_block(loghandle, &saved_index, index,
 276                                      &cur_offset, buf, LLOG_CHUNK_SIZE);
 277                 if (rc)
 278                         GOTO(out, rc);
 279
 280                 /* NB: when rec->lrh_len is accessed it is already swabbed
 281                  * since it is used at the "end" of the loop and the rec
 282                  * swabbing is done at the beginning of the loop. */
 283                 for (rec = (struct llog_rec_hdr *)buf;
 284                      (char *)rec < buf + LLOG_CHUNK_SIZE;
 285                      rec = (struct llog_rec_hdr *)((char *)rec + rec->lrh_len)){
 286
 287                         CDEBUG(D_OTHER, "processing rec 0x%p type %#x\n",
 288                                rec, rec->lrh_type);
 289
 290                         if (LLOG_REC_HDR_NEEDS_SWABBING(rec))
 291                                 lustre_swab_llog_rec(rec, NULL);
 292
 293                         CDEBUG(D_OTHER, "after swabbing, type=%#x idx=%d\n",
 294                                rec->lrh_type, rec->lrh_index);
 295
 296                         if (rec->lrh_index == 0)
 297                                 GOTO(out, 0); /* no more records */
 298
 299                         if (rec->lrh_len == 0 || rec->lrh_len >LLOG_CHUNK_SIZE){
 300                                 CWARN("invalid length %d in llog record for "
 301                                       "index %d/%d\n", rec->lrh_len,
 302                                       rec->lrh_index, index);
 303                                 GOTO(out, rc = -EINVAL);
 304                         }
 305
 306                         if (rec->lrh_index < index) {
 307                                 CDEBUG(D_OTHER, "skipping lrh_index %d\n",
 308                                        rec->lrh_index);
 309                                 continue;
 310                         }
 311
 312                         CDEBUG(D_OTHER,
 313                                "lrh_index: %d lrh_len: %d (%d remains)\n",
 314                                rec->lrh_index, rec->lrh_len,
 315                                (int)(buf + LLOG_CHUNK_SIZE - (char *)rec));
 316
 317                         loghandle->lgh_cur_idx = rec->lrh_index;
 318                         loghandle->lgh_cur_offset = (char *)rec - (char *)buf +
 319                                                     last_offset;
 320
 321                         /* if set, process the callback on this record */
 322                         if (ext2_test_bit(index, llh->llh_bitmap)) {
 323                                 rc = lpi->lpi_cb(loghandle, rec,
 324                                                  lpi->lpi_cbdata);
 325                                 last_called_index = index;
 326                                 if (rc == LLOG_PROC_BREAK) {
 327                                         GOTO(out, rc);
 328                                 } else if (rc == LLOG_DEL_RECORD) {
 329                                         llog_cancel_rec(loghandle,
 330                                                         rec->lrh_index);
 331                                         rc = 0;
 332                                 }
 333                                 if (rc)
 334                                         GOTO(out, rc);
 335                         } else {
 336                                 CDEBUG(D_OTHER, "Skipped index %d\n", index);
 337                         }
 338
 339                         /* next record, still in buffer? */
 340                         ++index;
 341                         if (index > last_index)
 342                                 GOTO(out, rc = 0);
 343                 }
 344         }
 345
 346  out:
 347         if (cd != NULL)
 348                 cd->lpcd_last_idx = last_called_index;
 349         if (buf)
 350                 OBD_FREE(buf, LLOG_CHUNK_SIZE);
 351         lpi->lpi_rc = rc;
 352 #ifdef __KERNEL__
 353         cfs_complete(&lpi->lpi_completion);
 354 #endif
 355         return 0;
 356 }
 357
 358 int llog_process_flags(struct llog_handle *loghandle, llog_cb_t cb,
 359                        void *data, void *catdata, int flags)
 360 {
 361         struct llog_process_info *lpi;
 362         int                      rc;
 363         ENTRY;
 364
 365         OBD_ALLOC_PTR(lpi);
 366         if (lpi == NULL) {
 367                 CERROR("cannot alloc pointer\n");
 368                 RETURN(-ENOMEM);
 369         }
 370         lpi->lpi_loghandle = loghandle;
 371         lpi->lpi_cb        = cb;
 372         lpi->lpi_cbdata    = data;
 373         lpi->lpi_catdata   = catdata;
 374         lpi->lpi_flags     = flags;
 375
 376 #ifdef __KERNEL__
 377         cfs_init_completion(&lpi->lpi_completion);
 378         rc = cfs_create_thread(llog_process_thread, lpi, CFS_DAEMON_FLAGS);
 379         if (rc < 0) {
 380                 CERROR("cannot start thread: %d\n", rc);
 381                 OBD_FREE_PTR(lpi);
 382                 RETURN(rc);
 383         }
 384         cfs_wait_for_completion(&lpi->lpi_completion);
 385 #else
 386         llog_process_thread(lpi);
 387 #endif
 388         rc = lpi->lpi_rc;
 389         OBD_FREE_PTR(lpi);
 390         RETURN(rc);
 391 }
 392 EXPORT_SYMBOL(llog_process_flags);
 393
 394 int llog_process(struct llog_handle *loghandle, llog_cb_t cb,
 395                  void *data, void *catdata)
 396 {
 397         return llog_process_flags(loghandle, cb, data, catdata, 0);
 398 }
 399 EXPORT_SYMBOL(llog_process);
 400
 401 inline int llog_get_size(struct llog_handle *loghandle)
 402 {
 403         if (loghandle && loghandle->lgh_hdr)
 404                 return loghandle->lgh_hdr->llh_count;
 405         return 0;
 406 }
 407 EXPORT_SYMBOL(llog_get_size);
 408
 409 int llog_reverse_process(struct llog_handle *loghandle, llog_cb_t cb,
 410                          void *data, void *catdata)
 411 {
 412         struct llog_log_hdr *llh = loghandle->lgh_hdr;
 413         struct llog_process_cat_data *cd = catdata;
 414         void *buf;
 415         int rc = 0, first_index = 1, index, idx;
 416         ENTRY;
 417
 418         OBD_ALLOC(buf, LLOG_CHUNK_SIZE);
 419         if (!buf)
 420                 RETURN(-ENOMEM);
 421
 422         if (cd != NULL)
 423                 first_index = cd->lpcd_first_idx + 1;
 424         if (cd != NULL && cd->lpcd_last_idx)
 425                 index = cd->lpcd_last_idx;
 426         else
 427                 index = LLOG_BITMAP_BYTES * 8 - 1;
 428
 429         while (rc == 0) {
 430                 struct llog_rec_hdr *rec;
 431                 struct llog_rec_tail *tail;
 432
 433                 /* skip records not set in bitmap */
 434                 while (index >= first_index &&
 435                        !ext2_test_bit(index, llh->llh_bitmap))
 436                         --index;
 437
 438                 LASSERT(index >= first_index - 1);
 439                 if (index == first_index - 1)
 440                         break;
 441
 442                 /* get the buf with our target record; avoid old garbage */
 443                 memset(buf, 0, LLOG_CHUNK_SIZE);
 444                 rc = llog_prev_block(loghandle, index, buf, LLOG_CHUNK_SIZE);
 445                 if (rc)
 446                         GOTO(out, rc);
 447
 448                 rec = buf;
 449                 idx = le32_to_cpu(rec->lrh_index);
 450                 if (idx < index)
 451                         CDEBUG(D_RPCTRACE, "index %u : idx %u\n", index, idx);
 452                 while (idx < index) {
 453                         rec = ((void *)rec + le32_to_cpu(rec->lrh_len));
 454                         idx ++;
 455                 }
 456                 tail = (void *)rec + le32_to_cpu(rec->lrh_len) - sizeof(*tail);
 457
 458                 /* process records in buffer, starting where we found one */
 459                 while ((void *)tail > buf) {
 460                         rec = (void *)tail - le32_to_cpu(tail->lrt_len) +
 461                                 sizeof(*tail);
 462
 463                         if (rec->lrh_index == 0)
 464                                 GOTO(out, 0); /* no more records */
 465
 466                         /* if set, process the callback on this record */
 467                         if (ext2_test_bit(index, llh->llh_bitmap)) {
 468                                 rc = cb(loghandle, rec, data);
 469                                 if (rc == LLOG_PROC_BREAK) {
 470                                         GOTO(out, rc);
 471                                 }
 472                                 if (rc)
 473                                         GOTO(out, rc);
 474                         }
 475
 476                         /* previous record, still in buffer? */
 477                         --index;
 478                         if (index < first_index)
 479                                 GOTO(out, rc = 0);
 480                         tail = (void *)rec - sizeof(*tail);
 481                 }
 482         }
 483
 484 out:
 485         if (buf)
 486                 OBD_FREE(buf, LLOG_CHUNK_SIZE);
 487         RETURN(rc);
 488 }
 489 EXPORT_SYMBOL(llog_reverse_process);