debugfs/logdump.c

   1 /*
   2  * logdump.c --- dump the contents of the journal out to a file
   3  *
   4  * Authro: Stephen C. Tweedie, 2001  <sct@redhat.com>
   5  * Copyright (C) 2001 Red Hat, Inc.
   6  * Based on portions  Copyright (C) 1994 Theodore Ts'o.
   7  *
   8  * This file may be redistributed under the terms of the GNU Public
   9  * License.
  10  */
  11
  12 #include <stdio.h>
  13 #include <unistd.h>
  14 #include <stdlib.h>
  15 #include <ctype.h>
  16 #include <string.h>
  17 #include <time.h>
  18 #ifdef HAVE_ERRNO_H
  19 #include <errno.h>
  20 #endif
  21 #include <sys/types.h>
  22 #include <sys/stat.h>
  23 #include <fcntl.h>
  24 #include <utime.h>
  25 #ifdef HAVE_GETOPT_H
  26 #include <getopt.h>
  27 #else
  28 extern int optind;
  29 extern char *optarg;
  30 #endif
  31 #ifdef HAVE_OPTRESET
  32 extern int optreset;            /* defined by BSD, but not others */
  33 #endif
  34
  35 #include "debugfs.h"
  36 #include "jfs_user.h"
  37
  38 enum journal_location {JOURNAL_IS_INTERNAL, JOURNAL_IS_EXTERNAL};
  39
  40 int             dump_all, dump_contents, dump_descriptors;
  41 unsigned int    block_to_dump, group_to_dump, bitmap_to_dump;
  42 unsigned int    inode_block_to_dump, inode_offset_to_dump, bitmap_to_dump;
  43 ext2_ino_t      inode_to_dump;
  44
  45 struct journal_source
  46 {
  47         enum journal_location where;
  48         int fd;
  49         ext2_file_t file;
  50 };
  51
  52 static void dump_journal(char *, FILE *, struct journal_source *);
  53
  54 static void dump_descriptor_block(FILE *, struct journal_source *,
  55                                   char *, journal_superblock_t *,
  56                                   unsigned int *, int, tid_t);
  57
  58 static void dump_revoke_block(FILE *, char *, journal_superblock_t *,
  59                                   unsigned int, int, tid_t);
  60
  61 static void dump_metadata_block(FILE *, struct journal_source *,
  62                                 journal_superblock_t*,
  63                                 unsigned int, unsigned int, int, tid_t);
  64
  65 static void do_hexdump (FILE *, char *, int);
  66
  67 #define WRAP(jsb, blocknr)                                      \
  68         if (blocknr >= be32_to_cpu((jsb)->s_maxlen))            \
  69                 blocknr -= (be32_to_cpu((jsb)->s_maxlen) -      \
  70                             be32_to_cpu((jsb)->s_first));
  71
  72
  73 void do_logdump(int argc, char **argv)
  74 {
  75         ext2_ino_t      inode;
  76         int             c;
  77         int             fd;
  78         int             retval;
  79         char            *out_fn;
  80         FILE            *out_file;
  81
  82         char            *inode_spec = NULL;
  83         char            *journal_fn = NULL;
  84         int             journal_fd = 0;
  85         ext2_ino_t      journal_inum;
  86         struct ext2_inode journal_inode;
  87         ext2_file_t     journal_file;
  88
  89         char            *tmp;
  90
  91         const char      *logdump_usage = ("Usage: logdump "
  92                                           "[-ac] [-b<block>] [-i<inode>] "
  93                                           "[-f<journal_file>] [output_file]");
  94
  95         struct journal_source journal_source = {};
  96
  97         optind = 0;
  98 #ifdef HAVE_OPTRESET
  99         optreset = 1;           /* Makes BSD getopt happy */
 100 #endif
 101         dump_all = 0;
 102         dump_contents = 0;
 103         dump_descriptors = 1;
 104         block_to_dump = -1;
 105         bitmap_to_dump = -1;
 106         inode_block_to_dump = -1;
 107         inode_to_dump = -1;
 108
 109         while ((c = getopt (argc, argv, "ab:ci:f:")) != EOF) {
 110                 switch (c) {
 111                 case 'a':
 112                         dump_all++;
 113                         break;
 114                 case 'b':
 115                         block_to_dump = strtoul(optarg, &tmp, 0);
 116                         if (*tmp) {
 117                                 com_err(argv[0], 0,
 118                                         "Bad block number - %s", optarg);
 119                                 return;
 120                         }
 121                         dump_descriptors = 0;
 122                         break;
 123                 case 'c':
 124                         dump_contents++;
 125                         break;
 126                 case 'f':
 127                         journal_fn = optarg;
 128                         break;
 129                 case 'i':
 130                         inode_spec = optarg;
 131                         dump_descriptors = 0;
 132                         break;
 133                 default:
 134                         com_err(argv[0], 0, logdump_usage);
 135                         return;
 136                 }
 137         }
 138         if (optind != argc && optind != argc-1) {
 139                 com_err(argv[0], 0, logdump_usage);
 140                 return;
 141         }
 142
 143         if (inode_spec) {
 144                 int inode_group, group_offset, inodes_per_block;
 145
 146                 if (check_fs_open(argv[0]))
 147                         return;
 148
 149                 inode_to_dump = string_to_inode(inode_spec);
 150                 if (!inode_to_dump)
 151                         return;
 152
 153                 inode_group = ((inode_to_dump - 1)
 154                                / current_fs->super->s_inodes_per_group);
 155                 group_offset = ((inode_to_dump - 1)
 156                                 % current_fs->super->s_inodes_per_group);
 157                 inodes_per_block = (current_fs->blocksize
 158                                     / sizeof(struct ext2_inode));
 159
 160                 inode_block_to_dump =
 161                         current_fs->group_desc[inode_group].bg_inode_table +
 162                         (group_offset / inodes_per_block);
 163                 inode_offset_to_dump = ((group_offset % inodes_per_block)
 164                                         * sizeof(struct ext2_inode));
 165                 printf("Inode %u is at group %u, block %u, offset %u\n",
 166                        inode_to_dump, inode_group,
 167                        inode_block_to_dump, inode_offset_to_dump);
 168         }
 169
 170         if (optind == argc) {
 171                 out_file = stdout;
 172         } else {
 173                 out_fn = argv[optind];
 174                 out_file = fopen(out_fn, "w");
 175                 if (!out_file < 0) {
 176                         com_err(argv[0], errno, "while opening %s for logdump",
 177                                 out_fn);
 178                         return;
 179                 }
 180         }
 181
 182         if (block_to_dump != -1 && current_fs != NULL) {
 183                 group_to_dump = ((block_to_dump -
 184                                   current_fs->super->s_first_data_block)
 185                                  / current_fs->super->s_blocks_per_group);
 186                 bitmap_to_dump = current_fs->group_desc[group_to_dump].bg_block_bitmap;
 187         }
 188
 189         if (journal_fn) {
 190
 191                 /* Set up to read journal from a regular file somewhere */
 192                 journal_fd = open(journal_fn, O_RDONLY, 0);
 193                 if (journal_fd < 0) {
 194                         com_err(argv[0], errno, "while opening %s for logdump",
 195                                 journal_fn);
 196                         return;
 197                 }
 198
 199                 journal_source.where = JOURNAL_IS_EXTERNAL;
 200                 journal_source.fd = journal_fd;
 201
 202         } else {
 203
 204                 /* Set up to read journal from the open filesystem */
 205                 if (check_fs_open(argv[0]))
 206                         return;
 207                 journal_inum = current_fs->super->s_journal_inum;
 208                 if (!journal_inum) {
 209                         com_err(argv[0], 0, "filesystem has no journal");
 210                         return;
 211                 }
 212
 213                 retval = ext2fs_read_inode(current_fs, journal_inum,
 214                                            &journal_inode);
 215                 if (retval) {
 216                         com_err(argv[0], retval,
 217                                 "while reading inode %u", journal_inum);
 218                         return;
 219                 }
 220
 221                 retval = ext2fs_file_open(current_fs, journal_inum,
 222                                           0, &journal_file);
 223                 if (retval) {
 224                         com_err(argv[0], retval, "while opening ext2 file");
 225                         return;
 226                 }
 227
 228                 journal_source.where = JOURNAL_IS_INTERNAL;
 229                 journal_source.file = journal_file;
 230         }
 231
 232         dump_journal(argv[0], out_file, &journal_source);
 233
 234         if (journal_source.where == JOURNAL_IS_INTERNAL)
 235                 ext2fs_file_close(journal_file);
 236         else
 237                 close(journal_fd);
 238
 239         if (out_file != stdout)
 240                 fclose(out_file);
 241
 242         return;
 243 }
 244
 245
 246 int read_journal_block(char *cmd, struct journal_source *source, off_t offset,
 247                        char *buf, int size, int *got)
 248 {
 249         int retval;
 250
 251         if (source->where == JOURNAL_IS_EXTERNAL) {
 252                 if (lseek(source->fd, offset, SEEK_SET) < 0) {
 253                         retval = errno;
 254                         com_err(cmd, retval, "while seeking in reading journal");
 255                         return retval;
 256                 }
 257                 retval = read(source->fd, buf, size);
 258                 if (retval >= 0) {
 259                         *got = retval;
 260                         retval = 0;
 261                 }
 262                 retval = errno;
 263         } else {
 264                 retval = ext2fs_file_lseek(source->file, offset,
 265                                            EXT2_SEEK_SET, NULL);
 266                 if (retval) {
 267                         com_err(cmd, retval, "while seeking in reading journal");
 268                         return retval;
 269                 }
 270
 271                 retval = ext2fs_file_read(source->file, buf, size, got);
 272         }
 273
 274         if (retval)
 275                 com_err(cmd, retval, "while while reading journal");
 276         else if (*got != size) {
 277                 com_err(cmd, 0, "short read (read %d, expected %d) while while reading journal", *got, size);
 278                 retval = -1;
 279         }
 280
 281         return retval;
 282 }
 283
 284 static char *type_to_name(int btype)
 285 {
 286         switch (btype) {
 287         case JFS_DESCRIPTOR_BLOCK:
 288                 return "descriptor block";
 289         case JFS_COMMIT_BLOCK:
 290                 return "commit block";
 291         case JFS_SUPERBLOCK_V1:
 292                 return "V1 superblock";
 293         case JFS_SUPERBLOCK_V2:
 294                 return "V2 superblock";
 295         case JFS_REVOKE_BLOCK:
 296                 return "revoke table";
 297         default:
 298         }
 299         return "unrecognised type";
 300 }
 301
 302
 303 static void dump_journal(char *cmdname, FILE *out_file,
 304                          struct journal_source *source)
 305 {
 306         char                    jsb_buffer[1024];
 307         char                    buf[8192];
 308         journal_superblock_t    *jsb;
 309         int                     blocksize;
 310         int                     got;
 311         int                     retval;
 312         __u32                   magic, sequence, blocktype;
 313         journal_header_t        *header;
 314
 315         tid_t                   transaction;
 316         unsigned int            blocknr;
 317
 318         /* First: locate the journal superblock */
 319
 320         retval = read_journal_block(cmdname, source, 0,
 321                                     jsb_buffer, 1024, &got);
 322         if (retval)
 323                 return;
 324
 325         jsb = (journal_superblock_t *) jsb_buffer;
 326         blocksize = be32_to_cpu(jsb->s_blocksize);
 327         transaction = be32_to_cpu(jsb->s_sequence);
 328         blocknr = be32_to_cpu(jsb->s_start);
 329
 330         fprintf(out_file, "Journal starts at block %u, transaction %u\n",
 331                 blocknr, transaction);
 332
 333         if (!blocknr)
 334                 /* Empty journal, nothing to do. */
 335                 return;
 336
 337         while (1) {
 338                 retval = read_journal_block(cmdname, source,
 339                                             blocknr*blocksize, buf,
 340                                             blocksize, &got);
 341                 if (retval || got != blocksize)
 342                         return;
 343
 344                 header = (journal_header_t *) buf;
 345
 346                 magic = be32_to_cpu(header->h_magic);
 347                 sequence = be32_to_cpu(header->h_sequence);
 348                 blocktype = be32_to_cpu(header->h_blocktype);
 349
 350                 if (magic != JFS_MAGIC_NUMBER) {
 351                         fprintf (out_file, "No magic number at block %u: "
 352                                  "end of journal.\n", blocknr);
 353                         return;
 354                 }
 355
 356                 if (sequence != transaction) {
 357                         fprintf (out_file, "Found sequence %u (not %u) at "
 358                                  "block %u: end of journal.\n",
 359                                  sequence, transaction, blocknr);
 360                         return;
 361                 }
 362
 363                 if (dump_descriptors) {
 364                         fprintf (out_file, "Found expected sequence %u, "
 365                                  "type %u (%s) at block %u\n",
 366                                  sequence, blocktype,
 367                                  type_to_name(blocktype), blocknr);
 368                 }
 369
 370                 switch (blocktype) {
 371                 case JFS_DESCRIPTOR_BLOCK:
 372                         dump_descriptor_block(out_file, source, buf, jsb,
 373                                               &blocknr, blocksize,
 374                                               transaction);
 375                         continue;
 376
 377                 case JFS_COMMIT_BLOCK:
 378                         transaction++;
 379                         blocknr++;
 380                         WRAP(jsb, blocknr);
 381                         continue;
 382
 383                 case JFS_REVOKE_BLOCK:
 384                         dump_revoke_block(out_file, buf, jsb,
 385                                           blocknr, blocksize,
 386                                           transaction);
 387                         blocknr++;
 388                         WRAP(jsb, blocknr);
 389                         continue;
 390
 391                 default:
 392                         fprintf (out_file, "Unexpected block type %u at "
 393                                  "block %u.\n", blocktype, blocknr);
 394                         return;
 395                 }
 396         }
 397 }
 398
 399
 400 static void dump_descriptor_block(FILE *out_file,
 401                                   struct journal_source *source,
 402                                   char *buf,
 403                                   journal_superblock_t *jsb,
 404                                   unsigned int *blockp, int blocksize,
 405                                   tid_t transaction)
 406 {
 407         int                     offset;
 408         char                    *tagp;
 409         journal_block_tag_t     *tag;
 410         unsigned int            blocknr;
 411         __u32                   tag_block;
 412         __u32                   tag_flags;
 413
 414
 415         offset = sizeof(journal_header_t);
 416         blocknr = *blockp;
 417
 418         if (dump_all)
 419                 fprintf(out_file, "Dumping descriptor block, sequence %u, at "
 420                         "block %u:\n", transaction, blocknr);
 421
 422         ++blocknr;
 423         WRAP(jsb, blocknr);
 424
 425         do {
 426                 /* Work out the location of the current tag, and skip to
 427                  * the next one... */
 428                 tagp = &buf[offset];
 429                 tag = (journal_block_tag_t *) tagp;
 430                 offset += sizeof(journal_block_tag_t);
 431
 432                 /* ... and if we have gone too far, then we've reached the
 433                    end of this block. */
 434                 if (offset > blocksize)
 435                         break;
 436
 437                 tag_block = be32_to_cpu(tag->t_blocknr);
 438                 tag_flags = be32_to_cpu(tag->t_flags);
 439
 440                 if (!(tag_flags & JFS_FLAG_SAME_UUID))
 441                         offset += 16;
 442
 443                 dump_metadata_block(out_file, source, jsb,
 444                                     blocknr, tag_block, blocksize,
 445                                     transaction);
 446
 447                 ++blocknr;
 448                 WRAP(jsb, blocknr);
 449
 450         } while (!(tag_flags & JFS_FLAG_LAST_TAG));
 451
 452         *blockp = blocknr;
 453 }
 454
 455
 456 static void dump_revoke_block(FILE *out_file, char *buf,
 457                                   journal_superblock_t *jsb,
 458                                   unsigned int blocknr, int blocksize,
 459                                   tid_t transaction)
 460 {
 461         int                     offset, max;
 462         journal_revoke_header_t *header;
 463         unsigned int            *entry, rblock;
 464
 465         if (dump_all)
 466                 fprintf(out_file, "Dumping revoke block, sequence %u, at "
 467                         "block %u:\n", transaction, blocknr);
 468
 469         header = (journal_revoke_header_t *) buf;
 470         offset = sizeof(journal_revoke_header_t);
 471         max = be32_to_cpu(header->r_count);
 472
 473         while (offset < max) {
 474                 entry = (unsigned int *) (buf + offset);
 475                 rblock = be32_to_cpu(*entry);
 476                 if (dump_all || rblock == block_to_dump) {
 477                         fprintf(out_file, "  Revoke FS block %u", rblock);
 478                         if (dump_all)
 479                                 fprintf(out_file, "\n");
 480                         else
 481                                 fprintf(out_file," at block %u, sequence %u\n",
 482                                         blocknr, transaction);
 483                 }
 484                 offset += 4;
 485         }
 486 }
 487
 488
 489 static void show_extent(FILE *out_file, int start_extent, int end_extent,
 490                         __u32 first_block)
 491 {
 492         if (start_extent >= 0 && first_block != 0)
 493                 fprintf(out_file, "(%d+%u): %u ",
 494                         start_extent, end_extent-start_extent, first_block);
 495 }
 496
 497 static void show_indirect(FILE *out_file, char *name, __u32 where)
 498 {
 499         if (where)
 500                 fprintf(out_file, "(%s): %u ", name, where);
 501 }
 502
 503
 504 static void dump_metadata_block(FILE *out_file, struct journal_source *source,
 505                                 journal_superblock_t *jsb,
 506                                 unsigned int log_blocknr,
 507                                 unsigned int fs_blocknr,
 508                                 int blocksize,
 509                                 tid_t transaction)
 510 {
 511         int got, retval;
 512         char buf[8192];
 513
 514         if (!(dump_all
 515               || (fs_blocknr == block_to_dump)
 516               || (fs_blocknr == inode_block_to_dump)
 517               || (fs_blocknr == bitmap_to_dump)))
 518                 return;
 519
 520         fprintf(out_file, "  FS block %u logged at ", fs_blocknr);
 521         if (!dump_all)
 522                 fprintf(out_file, "sequence %u, ", transaction);
 523         fprintf(out_file, "journal block %u\n", log_blocknr);
 524
 525         /* There are two major special cases to parse:
 526          *
 527          * If this block is a block
 528          * bitmap block, we need to give it special treatment so that we
 529          * can log any allocates and deallocates which affect the
 530          * block_to_dump query block.
 531          *
 532          * If the block is an inode block for the inode being searched
 533          * for, then we need to dump the contents of that inode
 534          * structure symbolically.
 535          */
 536
 537         if (!(dump_contents && dump_all)
 538             && fs_blocknr != block_to_dump
 539             && fs_blocknr != bitmap_to_dump
 540             && fs_blocknr != inode_block_to_dump)
 541                 return;
 542
 543         retval = read_journal_block("logdump", source,
 544                                     blocksize * log_blocknr,
 545                                     buf, blocksize, &got);
 546         if (retval)
 547                 return;
 548
 549         if (fs_blocknr == bitmap_to_dump) {
 550                 struct ext2_super_block *super;
 551                 int offset;
 552
 553                 super = current_fs->super;
 554                 offset = ((fs_blocknr - super->s_first_data_block) %
 555                           super->s_blocks_per_group);
 556
 557                 fprintf(out_file, "    (block bitmap for block %u: "
 558                         "block is %s)\n",
 559                         block_to_dump,
 560                         ext2fs_test_bit(offset, buf) ? "SET" : "CLEAR");
 561         }
 562
 563         if (fs_blocknr == inode_block_to_dump) {
 564                 struct ext2_inode *inode;
 565                 int first, prev, this, start_extent, i;
 566
 567                 fprintf(out_file, "    (inode block for inode %u):\n",
 568                         inode_to_dump);
 569
 570                 inode = (struct ext2_inode *) (buf + inode_offset_to_dump);
 571                 internal_dump_inode(out_file, "    ", inode_to_dump, inode, 0);
 572
 573                 /* Dump out the direct/indirect blocks here:
 574                  * internal_dump_inode can only dump them from the main
 575                  * on-disk inode, not from the journaled copy of the
 576                  * inode. */
 577
 578                 fprintf (out_file, "    Blocks:  ");
 579                 start_extent = -1;
 580
 581                 for (i=0; i<EXT2_NDIR_BLOCKS; i++) {
 582                         this = inode->i_block[i];
 583                         if (start_extent >= 0  && this == prev+1) {
 584                                 prev = this;
 585                                 continue;
 586                         } else {
 587                                 show_extent(out_file, start_extent, i, first);
 588                                 start_extent = i;
 589                                 first = prev = this;
 590                         }
 591                 }
 592                 show_extent(out_file, start_extent, i, first);
 593                 show_indirect(out_file, "IND", inode->i_block[i++]);
 594                 show_indirect(out_file, "DIND", inode->i_block[i++]);
 595                 show_indirect(out_file, "TIND", inode->i_block[i++]);
 596
 597                 fprintf(out_file, "\n");
 598         }
 599
 600         if (dump_contents)
 601                 do_hexdump(out_file, buf, blocksize);
 602
 603 }
 604
 605 static void do_hexdump (FILE *out_file, char *buf, int blocksize)
 606 {
 607         int i,j;
 608         int *intp;
 609         char *charp;
 610         unsigned char c;
 611
 612         intp = (int *) buf;
 613         charp = (char *) buf;
 614
 615         for (i=0; i<blocksize; i+=16) {
 616                 fprintf(out_file, "    %04x:  ", i);
 617                 for (j=0; j<16; j+=4)
 618                         fprintf(out_file, "%08x ", *intp++);
 619                 for (j=0; j<16; j++) {
 620                         c = *charp++;
 621                         if (c < ' ' || c >= 127)
 622                                 c = '.';
 623                         fprintf(out_file, "%c", c);
 624                 }
 625                 fprintf(out_file, "\n");
 626         }
 627 }
 628