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         int             c;
  76         int             retval;
  77         char            *out_fn;
  78         FILE            *out_file;
  79
  80         char            *inode_spec = NULL;
  81         char            *journal_fn = NULL;
  82         int             journal_fd = 0;
  83         ext2_ino_t      journal_inum;
  84         struct ext2_inode journal_inode;
  85         ext2_file_t     journal_file;
  86
  87         char            *tmp;
  88
  89         const char      *logdump_usage = ("Usage: logdump "
  90                                           "[-ac] [-b<block>] [-i<inode>] "
  91                                           "[-f<journal_file>] [output_file]");
  92
  93         struct journal_source journal_source;
  94
  95         optind = 0;
  96 #ifdef HAVE_OPTRESET
  97         optreset = 1;           /* Makes BSD getopt happy */
  98 #endif
  99         journal_source.where = 0;
 100         journal_source.fd = 0;
 101         journal_source.file = 0;
 102         dump_all = 0;
 103         dump_contents = 0;
 104         dump_descriptors = 1;
 105         block_to_dump = -1;
 106         bitmap_to_dump = -1;
 107         inode_block_to_dump = -1;
 108         inode_to_dump = -1;
 109
 110         while ((c = getopt (argc, argv, "ab:ci:f:")) != EOF) {
 111                 switch (c) {
 112                 case 'a':
 113                         dump_all++;
 114                         break;
 115                 case 'b':
 116                         block_to_dump = strtoul(optarg, &tmp, 0);
 117                         if (*tmp) {
 118                                 com_err(argv[0], 0,
 119                                         "Bad block number - %s", optarg);
 120                                 return;
 121                         }
 122                         dump_descriptors = 0;
 123                         break;
 124                 case 'c':
 125                         dump_contents++;
 126                         break;
 127                 case 'f':
 128                         journal_fn = optarg;
 129                         break;
 130                 case 'i':
 131                         inode_spec = optarg;
 132                         dump_descriptors = 0;
 133                         break;
 134                 default:
 135                         com_err(argv[0], 0, logdump_usage);
 136                         return;
 137                 }
 138         }
 139         if (optind != argc && optind != argc-1) {
 140                 com_err(argv[0], 0, logdump_usage);
 141                 return;
 142         }
 143
 144         if (inode_spec) {
 145                 int inode_group, group_offset, inodes_per_block;
 146
 147                 if (check_fs_open(argv[0]))
 148                         return;
 149
 150                 inode_to_dump = string_to_inode(inode_spec);
 151                 if (!inode_to_dump)
 152                         return;
 153
 154                 inode_group = ((inode_to_dump - 1)
 155                                / current_fs->super->s_inodes_per_group);
 156                 group_offset = ((inode_to_dump - 1)
 157                                 % current_fs->super->s_inodes_per_group);
 158                 inodes_per_block = (current_fs->blocksize
 159                                     / sizeof(struct ext2_inode));
 160
 161                 inode_block_to_dump =
 162                         current_fs->group_desc[inode_group].bg_inode_table +
 163                         (group_offset / inodes_per_block);
 164                 inode_offset_to_dump = ((group_offset % inodes_per_block)
 165                                         * sizeof(struct ext2_inode));
 166                 printf("Inode %u is at group %u, block %u, offset %u\n",
 167                        inode_to_dump, inode_group,
 168                        inode_block_to_dump, inode_offset_to_dump);
 169         }
 170
 171         if (optind == argc) {
 172                 out_file = stdout;
 173         } else {
 174                 out_fn = argv[optind];
 175                 out_file = fopen(out_fn, "w");
 176                 if (!out_file < 0) {
 177                         com_err(argv[0], errno, "while opening %s for logdump",
 178                                 out_fn);
 179                         return;
 180                 }
 181         }
 182
 183         if (block_to_dump != -1 && current_fs != NULL) {
 184                 group_to_dump = ((block_to_dump -
 185                                   current_fs->super->s_first_data_block)
 186                                  / current_fs->super->s_blocks_per_group);
 187                 bitmap_to_dump = current_fs->group_desc[group_to_dump].bg_block_bitmap;
 188         }
 189
 190         if (journal_fn) {
 191
 192                 /* Set up to read journal from a regular file somewhere */
 193                 journal_fd = open(journal_fn, O_RDONLY, 0);
 194                 if (journal_fd < 0) {
 195                         com_err(argv[0], errno, "while opening %s for logdump",
 196                                 journal_fn);
 197                         return;
 198                 }
 199
 200                 journal_source.where = JOURNAL_IS_EXTERNAL;
 201                 journal_source.fd = journal_fd;
 202
 203         } else {
 204
 205                 /* Set up to read journal from the open filesystem */
 206                 if (check_fs_open(argv[0]))
 207                         return;
 208                 journal_inum = current_fs->super->s_journal_inum;
 209                 if (!journal_inum) {
 210                         com_err(argv[0], 0, "filesystem has no journal");
 211                         return;
 212                 }
 213
 214                 retval = ext2fs_read_inode(current_fs, journal_inum,
 215                                            &journal_inode);
 216                 if (retval) {
 217                         com_err(argv[0], retval,
 218                                 "while reading inode %u", journal_inum);
 219                         return;
 220                 }
 221
 222                 retval = ext2fs_file_open(current_fs, journal_inum,
 223                                           0, &journal_file);
 224                 if (retval) {
 225                         com_err(argv[0], retval, "while opening ext2 file");
 226                         return;
 227                 }
 228
 229                 journal_source.where = JOURNAL_IS_INTERNAL;
 230                 journal_source.file = journal_file;
 231         }
 232
 233         dump_journal(argv[0], out_file, &journal_source);
 234
 235         if (journal_source.where == JOURNAL_IS_INTERNAL)
 236                 ext2fs_file_close(journal_file);
 237         else
 238                 close(journal_fd);
 239
 240         if (out_file != stdout)
 241                 fclose(out_file);
 242
 243         return;
 244 }
 245
 246
 247 static int read_journal_block(const char *cmd, struct journal_source *source,
 248                               off_t offset, char *buf, int size,
 249                               unsigned int *got)
 250 {
 251         int retval;
 252
 253         if (source->where == JOURNAL_IS_EXTERNAL) {
 254                 if (lseek(source->fd, offset, SEEK_SET) < 0) {
 255                         retval = errno;
 256                         com_err(cmd, retval, "while seeking in reading journal");
 257                         return retval;
 258                 }
 259                 retval = read(source->fd, buf, size);
 260                 if (retval >= 0) {
 261                         *got = retval;
 262                         retval = 0;
 263                 }
 264                 retval = errno;
 265         } else {
 266                 retval = ext2fs_file_lseek(source->file, offset,
 267                                            EXT2_SEEK_SET, NULL);
 268                 if (retval) {
 269                         com_err(cmd, retval, "while seeking in reading journal");
 270                         return retval;
 271                 }
 272
 273                 retval = ext2fs_file_read(source->file, buf, size, got);
 274         }
 275
 276         if (retval)
 277                 com_err(cmd, retval, "while while reading journal");
 278         else if (*got != size) {
 279                 com_err(cmd, 0, "short read (read %d, expected %d) while while reading journal", *got, size);
 280                 retval = -1;
 281         }
 282
 283         return retval;
 284 }
 285
 286 static const char *type_to_name(int btype)
 287 {
 288         switch (btype) {
 289         case JFS_DESCRIPTOR_BLOCK:
 290                 return "descriptor block";
 291         case JFS_COMMIT_BLOCK:
 292                 return "commit block";
 293         case JFS_SUPERBLOCK_V1:
 294                 return "V1 superblock";
 295         case JFS_SUPERBLOCK_V2:
 296                 return "V2 superblock";
 297         case JFS_REVOKE_BLOCK:
 298                 return "revoke table";
 299         }
 300         return "unrecognised type";
 301 }
 302
 303
 304 static void dump_journal(char *cmdname, FILE *out_file,
 305                          struct journal_source *source)
 306 {
 307         char                    jsb_buffer[1024];
 308         char                    buf[8192];
 309         journal_superblock_t    *jsb;
 310         int                     blocksize;
 311         unsigned int            got;
 312         int                     retval;
 313         __u32                   magic, sequence, blocktype;
 314         journal_header_t        *header;
 315
 316         tid_t                   transaction;
 317         unsigned int            blocknr;
 318
 319         /* First: locate the journal superblock */
 320
 321         retval = read_journal_block(cmdname, source, 0,
 322                                     jsb_buffer, 1024, &got);
 323         if (retval)
 324                 return;
 325
 326         jsb = (journal_superblock_t *) jsb_buffer;
 327         blocksize = be32_to_cpu(jsb->s_blocksize);
 328         transaction = be32_to_cpu(jsb->s_sequence);
 329         blocknr = be32_to_cpu(jsb->s_start);
 330
 331         fprintf(out_file, "Journal starts at block %u, transaction %u\n",
 332                 blocknr, transaction);
 333
 334         if (!blocknr)
 335                 /* Empty journal, nothing to do. */
 336                 return;
 337
 338         while (1) {
 339                 retval = read_journal_block(cmdname, source,
 340                                             blocknr*blocksize, buf,
 341                                             blocksize, &got);
 342                 if (retval || got != blocksize)
 343                         return;
 344
 345                 header = (journal_header_t *) buf;
 346
 347                 magic = be32_to_cpu(header->h_magic);
 348                 sequence = be32_to_cpu(header->h_sequence);
 349                 blocktype = be32_to_cpu(header->h_blocktype);
 350
 351                 if (magic != JFS_MAGIC_NUMBER) {
 352                         fprintf (out_file, "No magic number at block %u: "
 353                                  "end of journal.\n", blocknr);
 354                         return;
 355                 }
 356
 357                 if (sequence != transaction) {
 358                         fprintf (out_file, "Found sequence %u (not %u) at "
 359                                  "block %u: end of journal.\n",
 360                                  sequence, transaction, blocknr);
 361                         return;
 362                 }
 363
 364                 if (dump_descriptors) {
 365                         fprintf (out_file, "Found expected sequence %u, "
 366                                  "type %u (%s) at block %u\n",
 367                                  sequence, blocktype,
 368                                  type_to_name(blocktype), blocknr);
 369                 }
 370
 371                 switch (blocktype) {
 372                 case JFS_DESCRIPTOR_BLOCK:
 373                         dump_descriptor_block(out_file, source, buf, jsb,
 374                                               &blocknr, blocksize,
 375                                               transaction);
 376                         continue;
 377
 378                 case JFS_COMMIT_BLOCK:
 379                         transaction++;
 380                         blocknr++;
 381                         WRAP(jsb, blocknr);
 382                         continue;
 383
 384                 case JFS_REVOKE_BLOCK:
 385                         dump_revoke_block(out_file, buf, jsb,
 386                                           blocknr, blocksize,
 387                                           transaction);
 388                         blocknr++;
 389                         WRAP(jsb, blocknr);
 390                         continue;
 391
 392                 default:
 393                         fprintf (out_file, "Unexpected block type %u at "
 394                                  "block %u.\n", blocktype, blocknr);
 395                         return;
 396                 }
 397         }
 398 }
 399
 400
 401 static void dump_descriptor_block(FILE *out_file,
 402                                   struct journal_source *source,
 403                                   char *buf,
 404                                   journal_superblock_t *jsb,
 405                                   unsigned int *blockp, int blocksize,
 406                                   tid_t transaction)
 407 {
 408         int                     offset;
 409         char                    *tagp;
 410         journal_block_tag_t     *tag;
 411         unsigned int            blocknr;
 412         __u32                   tag_block;
 413         __u32                   tag_flags;
 414
 415
 416         offset = sizeof(journal_header_t);
 417         blocknr = *blockp;
 418
 419         if (dump_all)
 420                 fprintf(out_file, "Dumping descriptor block, sequence %u, at "
 421                         "block %u:\n", transaction, blocknr);
 422
 423         ++blocknr;
 424         WRAP(jsb, blocknr);
 425
 426         do {
 427                 /* Work out the location of the current tag, and skip to
 428                  * the next one... */
 429                 tagp = &buf[offset];
 430                 tag = (journal_block_tag_t *) tagp;
 431                 offset += sizeof(journal_block_tag_t);
 432
 433                 /* ... and if we have gone too far, then we've reached the
 434                    end of this block. */
 435                 if (offset > blocksize)
 436                         break;
 437
 438                 tag_block = be32_to_cpu(tag->t_blocknr);
 439                 tag_flags = be32_to_cpu(tag->t_flags);
 440
 441                 if (!(tag_flags & JFS_FLAG_SAME_UUID))
 442                         offset += 16;
 443
 444                 dump_metadata_block(out_file, source, jsb,
 445                                     blocknr, tag_block, blocksize,
 446                                     transaction);
 447
 448                 ++blocknr;
 449                 WRAP(jsb, blocknr);
 450
 451         } while (!(tag_flags & JFS_FLAG_LAST_TAG));
 452
 453         *blockp = blocknr;
 454 }
 455
 456
 457 static void dump_revoke_block(FILE *out_file, char *buf,
 458                                   journal_superblock_t *jsb,
 459                                   unsigned int blocknr, int blocksize,
 460                                   tid_t transaction)
 461 {
 462         int                     offset, max;
 463         journal_revoke_header_t *header;
 464         unsigned int            *entry, rblock;
 465
 466         if (dump_all)
 467                 fprintf(out_file, "Dumping revoke block, sequence %u, at "
 468                         "block %u:\n", transaction, blocknr);
 469
 470         header = (journal_revoke_header_t *) buf;
 471         offset = sizeof(journal_revoke_header_t);
 472         max = be32_to_cpu(header->r_count);
 473
 474         while (offset < max) {
 475                 entry = (unsigned int *) (buf + offset);
 476                 rblock = be32_to_cpu(*entry);
 477                 if (dump_all || rblock == block_to_dump) {
 478                         fprintf(out_file, "  Revoke FS block %u", rblock);
 479                         if (dump_all)
 480                                 fprintf(out_file, "\n");
 481                         else
 482                                 fprintf(out_file," at block %u, sequence %u\n",
 483                                         blocknr, transaction);
 484                 }
 485                 offset += 4;
 486         }
 487 }
 488
 489
 490 static void show_extent(FILE *out_file, int start_extent, int end_extent,
 491                         __u32 first_block)
 492 {
 493         if (start_extent >= 0 && first_block != 0)
 494                 fprintf(out_file, "(%d+%u): %u ",
 495                         start_extent, end_extent-start_extent, first_block);
 496 }
 497
 498 static void show_indirect(FILE *out_file, const char *name, __u32 where)
 499 {
 500         if (where)
 501                 fprintf(out_file, "(%s): %u ", name, where);
 502 }
 503
 504
 505 static void dump_metadata_block(FILE *out_file, struct journal_source *source,
 506                                 journal_superblock_t *jsb,
 507                                 unsigned int log_blocknr,
 508                                 unsigned int fs_blocknr,
 509                                 int blocksize,
 510                                 tid_t transaction)
 511 {
 512         unsigned int    got;
 513         int             retval;
 514         char            buf[8192];
 515
 516         if (!(dump_all
 517               || (fs_blocknr == block_to_dump)
 518               || (fs_blocknr == inode_block_to_dump)
 519               || (fs_blocknr == bitmap_to_dump)))
 520                 return;
 521
 522         fprintf(out_file, "  FS block %u logged at ", fs_blocknr);
 523         if (!dump_all)
 524                 fprintf(out_file, "sequence %u, ", transaction);
 525         fprintf(out_file, "journal block %u\n", log_blocknr);
 526
 527         /* There are two major special cases to parse:
 528          *
 529          * If this block is a block
 530          * bitmap block, we need to give it special treatment so that we
 531          * can log any allocates and deallocates which affect the
 532          * block_to_dump query block.
 533          *
 534          * If the block is an inode block for the inode being searched
 535          * for, then we need to dump the contents of that inode
 536          * structure symbolically.
 537          */
 538
 539         if (!(dump_contents && dump_all)
 540             && fs_blocknr != block_to_dump
 541             && fs_blocknr != bitmap_to_dump
 542             && fs_blocknr != inode_block_to_dump)
 543                 return;
 544
 545         retval = read_journal_block("logdump", source,
 546                                     blocksize * log_blocknr,
 547                                     buf, blocksize, &got);
 548         if (retval)
 549                 return;
 550
 551         if (fs_blocknr == bitmap_to_dump) {
 552                 struct ext2_super_block *super;
 553                 int offset;
 554
 555                 super = current_fs->super;
 556                 offset = ((fs_blocknr - super->s_first_data_block) %
 557                           super->s_blocks_per_group);
 558
 559                 fprintf(out_file, "    (block bitmap for block %u: "
 560                         "block is %s)\n",
 561                         block_to_dump,
 562                         ext2fs_test_bit(offset, buf) ? "SET" : "CLEAR");
 563         }
 564
 565         if (fs_blocknr == inode_block_to_dump) {
 566                 struct ext2_inode *inode;
 567                 int first, prev, this, start_extent, i;
 568
 569                 fprintf(out_file, "    (inode block for inode %u):\n",
 570                         inode_to_dump);
 571
 572                 inode = (struct ext2_inode *) (buf + inode_offset_to_dump);
 573                 internal_dump_inode(out_file, "    ", inode_to_dump, inode, 0);
 574
 575                 /* Dump out the direct/indirect blocks here:
 576                  * internal_dump_inode can only dump them from the main
 577                  * on-disk inode, not from the journaled copy of the
 578                  * inode. */
 579
 580                 fprintf (out_file, "    Blocks:  ");
 581                 first = prev = start_extent = -1;
 582
 583                 for (i=0; i<EXT2_NDIR_BLOCKS; i++) {
 584                         this = inode->i_block[i];
 585                         if (start_extent >= 0  && this == prev+1) {
 586                                 prev = this;
 587                                 continue;
 588                         } else {
 589                                 show_extent(out_file, start_extent, i, first);
 590                                 start_extent = i;
 591                                 first = prev = this;
 592                         }
 593                 }
 594                 show_extent(out_file, start_extent, i, first);
 595                 show_indirect(out_file, "IND", inode->i_block[i++]);
 596                 show_indirect(out_file, "DIND", inode->i_block[i++]);
 597                 show_indirect(out_file, "TIND", inode->i_block[i++]);
 598
 599                 fprintf(out_file, "\n");
 600         }
 601
 602         if (dump_contents)
 603                 do_hexdump(out_file, buf, blocksize);
 604
 605 }
 606
 607 static void do_hexdump (FILE *out_file, char *buf, int blocksize)
 608 {
 609         int i,j;
 610         int *intp;
 611         char *charp;
 612         unsigned char c;
 613
 614         intp = (int *) buf;
 615         charp = (char *) buf;
 616
 617         for (i=0; i<blocksize; i+=16) {
 618                 fprintf(out_file, "    %04x:  ", i);
 619                 for (j=0; j<16; j+=4)
 620                         fprintf(out_file, "%08x ", *intp++);
 621                 for (j=0; j<16; j++) {
 622                         c = *charp++;
 623                         if (c < ' ' || c >= 127)
 624                                 c = '.';
 625                         fprintf(out_file, "%c", c);
 626                 }
 627                 fprintf(out_file, "\n");
 628         }
 629 }
 630