e2fsck/journal.c

   1 /*
   2  * journal.c --- code for handling the "ext3" journal
   3  *
   4  * Copyright (C) 2000 Andreas Dilger
   5  * Copyright (C) 2000 Theodore Ts'o
   6  *
   7  * Parts of the code are based on fs/jfs/journal.c by Stephen C. Tweedie
   8  * Copyright (C) 1999 Red Hat Software
   9  *
  10  * This file may be redistributed under the terms of the
  11  * GNU General Public License version 2 or at your discretion
  12  * any later version.
  13  */
  14
  15 #ifdef HAVE_SYS_MOUNT_H
  16 #include <sys/param.h>
  17 #include <sys/mount.h>
  18 #define MNT_FL (MS_MGC_VAL | MS_RDONLY)
  19 #endif
  20 #ifdef HAVE_SYS_STAT_H
  21 #include <sys/stat.h>
  22 #endif
  23
  24 #define E2FSCK_INCLUDE_INLINE_FUNCS
  25 #include "jfs_user.h"
  26 #include "problem.h"
  27 #include "uuid/uuid.h"
  28
  29 #ifdef CONFIG_JBD_DEBUG         /* Enabled by configure --enable-jfs-debug */
  30 static int bh_count = 0;
  31 #endif
  32
  33 /*
  34  * Define USE_INODE_IO to use the inode_io.c / fileio.c codepaths.
  35  * This creates a larger static binary, and a smaller binary using
  36  * shared libraries.  It's also probably slightly less CPU-efficient,
  37  * which is why it's not on by default.  But, it's a good way of
  38  * testing the functions in inode_io.c and fileio.c.
  39  */
  40 #undef USE_INODE_IO
  41
  42 /* Kernel compatibility functions for handling the journal.  These allow us
  43  * to use the recovery.c file virtually unchanged from the kernel, so we
  44  * don't have to do much to keep kernel and user recovery in sync.
  45  */
  46 int journal_bmap(journal_t *journal, blk_t block, unsigned long *phys)
  47 {
  48 #ifdef USE_INODE_IO
  49         *phys = block;
  50         return 0;
  51 #else
  52         struct inode    *inode = journal->j_inode;
  53         errcode_t       retval;
  54         blk_t           pblk;
  55
  56         if (!inode) {
  57                 *phys = block;
  58                 return 0;
  59         }
  60
  61         retval= ext2fs_bmap(inode->i_ctx->fs, inode->i_ino,
  62                             &inode->i_ext2, NULL, 0, block, &pblk);
  63         *phys = pblk;
  64         return (retval);
  65 #endif
  66 }
  67
  68 struct buffer_head *getblk(kdev_t kdev, blk_t blocknr, int blocksize)
  69 {
  70         struct buffer_head *bh;
  71
  72         bh = e2fsck_allocate_memory(kdev->k_ctx, sizeof(*bh), "block buffer");
  73         if (!bh)
  74                 return NULL;
  75
  76         jfs_debug(4, "getblk for block %lu (%d bytes)(total %d)\n",
  77                   (unsigned long) blocknr, blocksize, ++bh_count);
  78
  79         bh->b_ctx = kdev->k_ctx;
  80         if (kdev->k_dev == K_DEV_FS)
  81                 bh->b_io = kdev->k_ctx->fs->io;
  82         else
  83                 bh->b_io = kdev->k_ctx->journal_io;
  84         bh->b_size = blocksize;
  85         bh->b_blocknr = blocknr;
  86
  87         return bh;
  88 }
  89
  90 void sync_blockdev(kdev_t kdev)
  91 {
  92         io_channel      io;
  93
  94         if (kdev->k_dev == K_DEV_FS)
  95                 io = kdev->k_ctx->fs->io;
  96         else
  97                 io = kdev->k_ctx->journal_io;
  98
  99         io_channel_flush(io);
 100 }
 101
 102 void ll_rw_block(int rw, int nr, struct buffer_head *bhp[])
 103 {
 104         int retval;
 105         struct buffer_head *bh;
 106
 107         for (; nr > 0; --nr) {
 108                 bh = *bhp++;
 109                 if (rw == READ && !bh->b_uptodate) {
 110                         jfs_debug(3, "reading block %lu/%p\n",
 111                                   (unsigned long) bh->b_blocknr, (void *) bh);
 112                         retval = io_channel_read_blk(bh->b_io,
 113                                                      bh->b_blocknr,
 114                                                      1, bh->b_data);
 115                         if (retval) {
 116                                 com_err(bh->b_ctx->device_name, retval,
 117                                         "while reading block %lu\n",
 118                                         (unsigned long) bh->b_blocknr);
 119                                 bh->b_err = retval;
 120                                 continue;
 121                         }
 122                         bh->b_uptodate = 1;
 123                 } else if (rw == WRITE && bh->b_dirty) {
 124                         jfs_debug(3, "writing block %lu/%p\n",
 125                                   (unsigned long) bh->b_blocknr, (void *) bh);
 126                         retval = io_channel_write_blk(bh->b_io,
 127                                                       bh->b_blocknr,
 128                                                       1, bh->b_data);
 129                         if (retval) {
 130                                 com_err(bh->b_ctx->device_name, retval,
 131                                         "while writing block %lu\n",
 132                                         (unsigned long) bh->b_blocknr);
 133                                 bh->b_err = retval;
 134                                 continue;
 135                         }
 136                         bh->b_dirty = 0;
 137                         bh->b_uptodate = 1;
 138                 } else {
 139                         jfs_debug(3, "no-op %s for block %lu\n",
 140                                   rw == READ ? "read" : "write",
 141                                   (unsigned long) bh->b_blocknr);
 142                 }
 143         }
 144 }
 145
 146 void mark_buffer_dirty(struct buffer_head *bh)
 147 {
 148         bh->b_dirty = 1;
 149 }
 150
 151 static void mark_buffer_clean(struct buffer_head * bh)
 152 {
 153         bh->b_dirty = 0;
 154 }
 155
 156 void brelse(struct buffer_head *bh)
 157 {
 158         if (bh->b_dirty)
 159                 ll_rw_block(WRITE, 1, &bh);
 160         jfs_debug(3, "freeing block %lu/%p (total %d)\n",
 161                   (unsigned long) bh->b_blocknr, (void *) bh, --bh_count);
 162         ext2fs_free_mem(&bh);
 163 }
 164
 165 int buffer_uptodate(struct buffer_head *bh)
 166 {
 167         return bh->b_uptodate;
 168 }
 169
 170 void mark_buffer_uptodate(struct buffer_head *bh, int val)
 171 {
 172         bh->b_uptodate = val;
 173 }
 174
 175 void wait_on_buffer(struct buffer_head *bh)
 176 {
 177         if (!bh->b_uptodate)
 178                 ll_rw_block(READ, 1, &bh);
 179 }
 180
 181
 182 static void e2fsck_clear_recover(e2fsck_t ctx, int error)
 183 {
 184         ctx->fs->super->s_feature_incompat &= ~EXT3_FEATURE_INCOMPAT_RECOVER;
 185
 186         /* if we had an error doing journal recovery, we need a full fsck */
 187         if (error)
 188                 ctx->fs->super->s_state &= ~EXT2_VALID_FS;
 189         ext2fs_mark_super_dirty(ctx->fs);
 190 }
 191
 192 /*
 193  * This is a helper function to check the validity of the journal.
 194  */
 195 struct process_block_struct {
 196         e2_blkcnt_t     last_block;
 197 };
 198
 199 static int process_journal_block(ext2_filsys fs,
 200                                  blk_t  *block_nr,
 201                                  e2_blkcnt_t blockcnt,
 202                                  blk_t ref_block EXT2FS_ATTR((unused)),
 203                                  int ref_offset EXT2FS_ATTR((unused)),
 204                                  void *priv_data)
 205 {
 206         struct process_block_struct *p;
 207         blk_t   blk = *block_nr;
 208
 209         p = (struct process_block_struct *) priv_data;
 210
 211         if (blk < fs->super->s_first_data_block ||
 212             blk >= fs->super->s_blocks_count)
 213                 return BLOCK_ABORT;
 214
 215         if (blockcnt >= 0)
 216                 p->last_block = blockcnt;
 217         return 0;
 218 }
 219
 220 static errcode_t e2fsck_get_journal(e2fsck_t ctx, journal_t **ret_journal)
 221 {
 222         struct process_block_struct pb;
 223         struct ext2_super_block *sb = ctx->fs->super;
 224         struct ext2_super_block jsuper;
 225         struct problem_context  pctx;
 226         struct buffer_head      *bh;
 227         struct inode            *j_inode = NULL;
 228         struct kdev_s           *dev_fs = NULL, *dev_journal;
 229         const char              *journal_name = 0;
 230         journal_t               *journal = NULL;
 231         errcode_t               retval = 0;
 232         io_manager              io_ptr = 0;
 233         unsigned long           start = 0;
 234         int                     ext_journal = 0;
 235         int                     tried_backup_jnl = 0;
 236
 237         clear_problem_context(&pctx);
 238
 239         journal = e2fsck_allocate_memory(ctx, sizeof(journal_t), "journal");
 240         if (!journal) {
 241                 return EXT2_ET_NO_MEMORY;
 242         }
 243
 244         dev_fs = e2fsck_allocate_memory(ctx, 2*sizeof(struct kdev_s), "kdev");
 245         if (!dev_fs) {
 246                 retval = EXT2_ET_NO_MEMORY;
 247                 goto errout;
 248         }
 249         dev_journal = dev_fs+1;
 250
 251         dev_fs->k_ctx = dev_journal->k_ctx = ctx;
 252         dev_fs->k_dev = K_DEV_FS;
 253         dev_journal->k_dev = K_DEV_JOURNAL;
 254
 255         journal->j_dev = dev_journal;
 256         journal->j_fs_dev = dev_fs;
 257         journal->j_inode = NULL;
 258         journal->j_blocksize = ctx->fs->blocksize;
 259
 260         if (uuid_is_null(sb->s_journal_uuid)) {
 261                 if (!sb->s_journal_inum) {
 262                         retval = EXT2_ET_BAD_INODE_NUM;
 263                         goto errout;
 264                 }
 265                 j_inode = e2fsck_allocate_memory(ctx, sizeof(*j_inode),
 266                                                  "journal inode");
 267                 if (!j_inode) {
 268                         retval = EXT2_ET_NO_MEMORY;
 269                         goto errout;
 270                 }
 271
 272                 j_inode->i_ctx = ctx;
 273                 j_inode->i_ino = sb->s_journal_inum;
 274
 275                 if ((retval = ext2fs_read_inode(ctx->fs,
 276                                                 sb->s_journal_inum,
 277                                                 &j_inode->i_ext2))) {
 278                 try_backup_journal:
 279                         if (sb->s_jnl_backup_type != EXT3_JNL_BACKUP_BLOCKS ||
 280                             tried_backup_jnl)
 281                                 goto errout;
 282                         memset(&j_inode->i_ext2, 0, sizeof(struct ext2_inode));
 283                         memcpy(&j_inode->i_ext2.i_block[0], sb->s_jnl_blocks,
 284                                EXT2_N_BLOCKS*4);
 285                         j_inode->i_ext2.i_size = sb->s_jnl_blocks[16];
 286                         j_inode->i_ext2.i_links_count = 1;
 287                         j_inode->i_ext2.i_mode = LINUX_S_IFREG | 0600;
 288                         e2fsck_use_inode_shortcuts(ctx, 1);
 289                         ctx->stashed_ino = j_inode->i_ino;
 290                         ctx->stashed_inode = &j_inode->i_ext2;
 291                         tried_backup_jnl++;
 292                 }
 293                 if (!j_inode->i_ext2.i_links_count ||
 294                     !LINUX_S_ISREG(j_inode->i_ext2.i_mode)) {
 295                         retval = EXT2_ET_NO_JOURNAL;
 296                         goto try_backup_journal;
 297                 }
 298                 if (j_inode->i_ext2.i_size / journal->j_blocksize <
 299                     JFS_MIN_JOURNAL_BLOCKS) {
 300                         retval = EXT2_ET_JOURNAL_TOO_SMALL;
 301                         goto try_backup_journal;
 302                 }
 303                 pb.last_block = -1;
 304                 retval = ext2fs_block_iterate2(ctx->fs, j_inode->i_ino,
 305                                                BLOCK_FLAG_HOLE, 0,
 306                                                process_journal_block, &pb);
 307                 if ((pb.last_block+1) * ctx->fs->blocksize <
 308                     j_inode->i_ext2.i_size) {
 309                         retval = EXT2_ET_JOURNAL_TOO_SMALL;
 310                         goto try_backup_journal;
 311                 }
 312                 if (tried_backup_jnl && !(ctx->options & E2F_OPT_READONLY)) {
 313                         retval = ext2fs_write_inode(ctx->fs, sb->s_journal_inum,
 314                                                     &j_inode->i_ext2);
 315                         if (retval)
 316                                 goto errout;
 317                 }
 318
 319                 journal->j_maxlen = j_inode->i_ext2.i_size / journal->j_blocksize;
 320
 321 #ifdef USE_INODE_IO
 322                 retval = ext2fs_inode_io_intern2(ctx->fs, sb->s_journal_inum,
 323                                                  &j_inode->i_ext2,
 324                                                  &journal_name);
 325                 if (retval)
 326                         goto errout;
 327
 328                 io_ptr = inode_io_manager;
 329 #else
 330                 journal->j_inode = j_inode;
 331                 ctx->journal_io = ctx->fs->io;
 332                 if ((retval = journal_bmap(journal, 0, &start)) != 0)
 333                         goto errout;
 334 #endif
 335         } else {
 336                 ext_journal = 1;
 337                 if (!ctx->journal_name) {
 338                         char uuid[37];
 339
 340                         uuid_unparse(sb->s_journal_uuid, uuid);
 341                         ctx->journal_name = blkid_get_devname(ctx->blkid,
 342                                                               "UUID", uuid);
 343                         if (!ctx->journal_name)
 344                                 ctx->journal_name = blkid_devno_to_devname(sb->s_journal_dev);
 345                 }
 346                 journal_name = ctx->journal_name;
 347
 348                 if (!journal_name) {
 349                         fix_problem(ctx, PR_0_CANT_FIND_JOURNAL, &pctx);
 350                         retval = EXT2_ET_LOAD_EXT_JOURNAL;
 351                         goto errout;
 352                 }
 353
 354                 jfs_debug(1, "Using journal file %s\n", journal_name);
 355                 io_ptr = unix_io_manager;
 356         }
 357
 358 #if 0
 359         test_io_backing_manager = io_ptr;
 360         io_ptr = test_io_manager;
 361 #endif
 362 #ifndef USE_INODE_IO
 363         if (ext_journal)
 364 #endif
 365                 retval = io_ptr->open(journal_name, IO_FLAG_RW,
 366                                       &ctx->journal_io);
 367         if (retval)
 368                 goto errout;
 369
 370         io_channel_set_blksize(ctx->journal_io, ctx->fs->blocksize);
 371
 372         if (ext_journal) {
 373                 if (ctx->fs->blocksize == 1024)
 374                         start = 1;
 375                 bh = getblk(dev_journal, start, ctx->fs->blocksize);
 376                 if (!bh) {
 377                         retval = EXT2_ET_NO_MEMORY;
 378                         goto errout;
 379                 }
 380                 ll_rw_block(READ, 1, &bh);
 381                 if ((retval = bh->b_err) != 0) {
 382                         brelse(bh);
 383                         goto errout;
 384                 }
 385                 memcpy(&jsuper, start ? bh->b_data :  bh->b_data + 1024,
 386                        sizeof(jsuper));
 387                 brelse(bh);
 388 #ifdef EXT2FS_ENABLE_SWAPFS
 389                 if (jsuper.s_magic == ext2fs_swab16(EXT2_SUPER_MAGIC))
 390                         ext2fs_swap_super(&jsuper);
 391 #endif
 392                 if (jsuper.s_magic != EXT2_SUPER_MAGIC ||
 393                     !(jsuper.s_feature_incompat & EXT3_FEATURE_INCOMPAT_JOURNAL_DEV)) {
 394                         fix_problem(ctx, PR_0_EXT_JOURNAL_BAD_SUPER, &pctx);
 395                         retval = EXT2_ET_LOAD_EXT_JOURNAL;
 396                         goto errout;
 397                 }
 398                 /* Make sure the journal UUID is correct */
 399                 if (memcmp(jsuper.s_uuid, ctx->fs->super->s_journal_uuid,
 400                            sizeof(jsuper.s_uuid))) {
 401                         fix_problem(ctx, PR_0_JOURNAL_BAD_UUID, &pctx);
 402                         retval = EXT2_ET_LOAD_EXT_JOURNAL;
 403                         goto errout;
 404                 }
 405
 406                 journal->j_maxlen = jsuper.s_blocks_count;
 407                 start++;
 408         }
 409
 410         if (!(bh = getblk(dev_journal, start, journal->j_blocksize))) {
 411                 retval = EXT2_ET_NO_MEMORY;
 412                 goto errout;
 413         }
 414
 415         journal->j_sb_buffer = bh;
 416         journal->j_superblock = (journal_superblock_t *)bh->b_data;
 417
 418 #ifdef USE_INODE_IO
 419         if (j_inode)
 420                 ext2fs_free_mem(&j_inode);
 421 #endif
 422
 423         *ret_journal = journal;
 424         e2fsck_use_inode_shortcuts(ctx, 0);
 425         return 0;
 426
 427 errout:
 428         e2fsck_use_inode_shortcuts(ctx, 0);
 429         if (dev_fs)
 430                 ext2fs_free_mem(&dev_fs);
 431         if (j_inode)
 432                 ext2fs_free_mem(&j_inode);
 433         if (journal)
 434                 ext2fs_free_mem(&journal);
 435         return retval;
 436 }
 437
 438 static errcode_t e2fsck_journal_fix_bad_inode(e2fsck_t ctx,
 439                                               struct problem_context *pctx)
 440 {
 441         struct ext2_super_block *sb = ctx->fs->super;
 442         int recover = ctx->fs->super->s_feature_incompat &
 443                 EXT3_FEATURE_INCOMPAT_RECOVER;
 444         int has_journal = ctx->fs->super->s_feature_compat &
 445                 EXT3_FEATURE_COMPAT_HAS_JOURNAL;
 446
 447         if (has_journal || sb->s_journal_inum) {
 448                 /* The journal inode is bogus, remove and force full fsck */
 449                 pctx->ino = sb->s_journal_inum;
 450                 if (fix_problem(ctx, PR_0_JOURNAL_BAD_INODE, pctx)) {
 451                         if (has_journal && sb->s_journal_inum)
 452                                 printf("*** ext3 journal has been deleted - "
 453                                        "filesystem is now ext2 only ***\n\n");
 454                         sb->s_feature_compat &= ~EXT3_FEATURE_COMPAT_HAS_JOURNAL;
 455                         sb->s_journal_inum = 0;
 456                         ctx->flags |= E2F_FLAG_JOURNAL_INODE;
 457                         ctx->fs->flags &= ~EXT2_FLAG_MASTER_SB_ONLY;
 458                         e2fsck_clear_recover(ctx, 1);
 459                         return 0;
 460                 }
 461                 return EXT2_ET_BAD_INODE_NUM;
 462         } else if (recover) {
 463                 if (fix_problem(ctx, PR_0_JOURNAL_RECOVER_SET, pctx)) {
 464                         e2fsck_clear_recover(ctx, 1);
 465                         return 0;
 466                 }
 467                 return EXT2_ET_UNSUPP_FEATURE;
 468         }
 469         return 0;
 470 }
 471
 472 #define V1_SB_SIZE      0x0024
 473 static void clear_v2_journal_fields(journal_t *journal)
 474 {
 475         e2fsck_t ctx = journal->j_dev->k_ctx;
 476         struct problem_context pctx;
 477
 478         clear_problem_context(&pctx);
 479
 480         if (!fix_problem(ctx, PR_0_CLEAR_V2_JOURNAL, &pctx))
 481                 return;
 482
 483         memset(((char *) journal->j_superblock) + V1_SB_SIZE, 0,
 484                ctx->fs->blocksize-V1_SB_SIZE);
 485         mark_buffer_dirty(journal->j_sb_buffer);
 486 }
 487
 488
 489 static errcode_t e2fsck_journal_load(journal_t *journal)
 490 {
 491         e2fsck_t ctx = journal->j_dev->k_ctx;
 492         journal_superblock_t *jsb;
 493         struct buffer_head *jbh = journal->j_sb_buffer;
 494         struct problem_context pctx;
 495
 496         clear_problem_context(&pctx);
 497
 498         ll_rw_block(READ, 1, &jbh);
 499         if (jbh->b_err) {
 500                 com_err(ctx->device_name, jbh->b_err,
 501                         _("reading journal superblock\n"));
 502                 return jbh->b_err;
 503         }
 504
 505         jsb = journal->j_superblock;
 506         /* If we don't even have JFS_MAGIC, we probably have a wrong inode */
 507         if (jsb->s_header.h_magic != htonl(JFS_MAGIC_NUMBER))
 508                 return e2fsck_journal_fix_bad_inode(ctx, &pctx);
 509
 510         switch (ntohl(jsb->s_header.h_blocktype)) {
 511         case JFS_SUPERBLOCK_V1:
 512                 journal->j_format_version = 1;
 513                 if (jsb->s_feature_compat ||
 514                     jsb->s_feature_incompat ||
 515                     jsb->s_feature_ro_compat ||
 516                     jsb->s_nr_users)
 517                         clear_v2_journal_fields(journal);
 518                 break;
 519
 520         case JFS_SUPERBLOCK_V2:
 521                 journal->j_format_version = 2;
 522                 if (ntohl(jsb->s_nr_users) > 1 &&
 523                     uuid_is_null(ctx->fs->super->s_journal_uuid))
 524                         clear_v2_journal_fields(journal);
 525                 if (ntohl(jsb->s_nr_users) > 1) {
 526                         fix_problem(ctx, PR_0_JOURNAL_UNSUPP_MULTIFS, &pctx);
 527                         return EXT2_ET_JOURNAL_UNSUPP_VERSION;
 528                 }
 529                 break;
 530
 531         /*
 532          * These should never appear in a journal super block, so if
 533          * they do, the journal is badly corrupted.
 534          */
 535         case JFS_DESCRIPTOR_BLOCK:
 536         case JFS_COMMIT_BLOCK:
 537         case JFS_REVOKE_BLOCK:
 538                 return EXT2_ET_CORRUPT_SUPERBLOCK;
 539
 540         /* If we don't understand the superblock major type, but there
 541          * is a magic number, then it is likely to be a new format we
 542          * just don't understand, so leave it alone. */
 543         default:
 544                 return EXT2_ET_JOURNAL_UNSUPP_VERSION;
 545         }
 546
 547         if (JFS_HAS_INCOMPAT_FEATURE(journal, ~JFS_KNOWN_INCOMPAT_FEATURES))
 548                 return EXT2_ET_UNSUPP_FEATURE;
 549
 550         if (JFS_HAS_RO_COMPAT_FEATURE(journal, ~JFS_KNOWN_ROCOMPAT_FEATURES))
 551                 return EXT2_ET_RO_UNSUPP_FEATURE;
 552
 553         /* We have now checked whether we know enough about the journal
 554          * format to be able to proceed safely, so any other checks that
 555          * fail we should attempt to recover from. */
 556         if (jsb->s_blocksize != htonl(journal->j_blocksize)) {
 557                 com_err(ctx->program_name, EXT2_ET_CORRUPT_SUPERBLOCK,
 558                         _("%s: no valid journal superblock found\n"),
 559                         ctx->device_name);
 560                 return EXT2_ET_CORRUPT_SUPERBLOCK;
 561         }
 562
 563         if (ntohl(jsb->s_maxlen) < journal->j_maxlen)
 564                 journal->j_maxlen = ntohl(jsb->s_maxlen);
 565         else if (ntohl(jsb->s_maxlen) > journal->j_maxlen) {
 566                 com_err(ctx->program_name, EXT2_ET_CORRUPT_SUPERBLOCK,
 567                         _("%s: journal too short\n"),
 568                         ctx->device_name);
 569                 return EXT2_ET_CORRUPT_SUPERBLOCK;
 570         }
 571
 572         journal->j_tail_sequence = ntohl(jsb->s_sequence);
 573         journal->j_transaction_sequence = journal->j_tail_sequence;
 574         journal->j_tail = ntohl(jsb->s_start);
 575         journal->j_first = ntohl(jsb->s_first);
 576         journal->j_last = ntohl(jsb->s_maxlen);
 577
 578         return 0;
 579 }
 580
 581 static void e2fsck_journal_reset_super(e2fsck_t ctx, journal_superblock_t *jsb,
 582                                        journal_t *journal)
 583 {
 584         char *p;
 585         union {
 586                 uuid_t uuid;
 587                 __u32 val[4];
 588         } u;
 589         __u32 new_seq = 0;
 590         int i;
 591
 592         /* Leave a valid existing V1 superblock signature alone.
 593          * Anything unrecognisable we overwrite with a new V2
 594          * signature. */
 595
 596         if (jsb->s_header.h_magic != htonl(JFS_MAGIC_NUMBER) ||
 597             jsb->s_header.h_blocktype != htonl(JFS_SUPERBLOCK_V1)) {
 598                 jsb->s_header.h_magic = htonl(JFS_MAGIC_NUMBER);
 599                 jsb->s_header.h_blocktype = htonl(JFS_SUPERBLOCK_V2);
 600         }
 601
 602         /* Zero out everything else beyond the superblock header */
 603
 604         p = ((char *) jsb) + sizeof(journal_header_t);
 605         memset (p, 0, ctx->fs->blocksize-sizeof(journal_header_t));
 606
 607         jsb->s_blocksize = htonl(ctx->fs->blocksize);
 608         jsb->s_maxlen = htonl(journal->j_maxlen);
 609         jsb->s_first = htonl(1);
 610
 611         /* Initialize the journal sequence number so that there is "no"
 612          * chance we will find old "valid" transactions in the journal.
 613          * This avoids the need to zero the whole journal (slow to do,
 614          * and risky when we are just recovering the filesystem).
 615          */
 616         uuid_generate(u.uuid);
 617         for (i = 0; i < 4; i ++)
 618                 new_seq ^= u.val[i];
 619         jsb->s_sequence = htonl(new_seq);
 620
 621         mark_buffer_dirty(journal->j_sb_buffer);
 622         ll_rw_block(WRITE, 1, &journal->j_sb_buffer);
 623 }
 624
 625 static errcode_t e2fsck_journal_fix_corrupt_super(e2fsck_t ctx,
 626                                                   journal_t *journal,
 627                                                   struct problem_context *pctx)
 628 {
 629         struct ext2_super_block *sb = ctx->fs->super;
 630         int recover = ctx->fs->super->s_feature_incompat &
 631                 EXT3_FEATURE_INCOMPAT_RECOVER;
 632
 633         if (sb->s_feature_compat & EXT3_FEATURE_COMPAT_HAS_JOURNAL) {
 634                 if (fix_problem(ctx, PR_0_JOURNAL_BAD_SUPER, pctx)) {
 635                         e2fsck_journal_reset_super(ctx, journal->j_superblock,
 636                                                    journal);
 637                         journal->j_transaction_sequence = 1;
 638                         e2fsck_clear_recover(ctx, recover);
 639                         return 0;
 640                 }
 641                 return EXT2_ET_CORRUPT_SUPERBLOCK;
 642         } else if (e2fsck_journal_fix_bad_inode(ctx, pctx))
 643                 return EXT2_ET_CORRUPT_SUPERBLOCK;
 644
 645         return 0;
 646 }
 647
 648 static void e2fsck_journal_release(e2fsck_t ctx, journal_t *journal,
 649                                    int reset, int drop)
 650 {
 651         journal_superblock_t *jsb;
 652
 653         if (drop)
 654                 mark_buffer_clean(journal->j_sb_buffer);
 655         else if (!(ctx->options & E2F_OPT_READONLY)) {
 656                 jsb = journal->j_superblock;
 657                 jsb->s_sequence = htonl(journal->j_transaction_sequence);
 658                 if (reset)
 659                         jsb->s_start = 0; /* this marks the journal as empty */
 660                 mark_buffer_dirty(journal->j_sb_buffer);
 661         }
 662         brelse(journal->j_sb_buffer);
 663
 664         if (ctx->journal_io) {
 665                 if (ctx->fs && ctx->fs->io != ctx->journal_io)
 666                         io_channel_close(ctx->journal_io);
 667                 ctx->journal_io = 0;
 668         }
 669
 670 #ifndef USE_INODE_IO
 671         if (journal->j_inode)
 672                 ext2fs_free_mem(&journal->j_inode);
 673 #endif
 674         if (journal->j_fs_dev)
 675                 ext2fs_free_mem(&journal->j_fs_dev);
 676         ext2fs_free_mem(&journal);
 677 }
 678
 679 /*
 680  * This function makes sure that the superblock fields regarding the
 681  * journal are consistent.
 682  */
 683 int e2fsck_check_ext3_journal(e2fsck_t ctx)
 684 {
 685         struct ext2_super_block *sb = ctx->fs->super;
 686         journal_t *journal;
 687         int recover = ctx->fs->super->s_feature_incompat &
 688                 EXT3_FEATURE_INCOMPAT_RECOVER;
 689         struct problem_context pctx;
 690         problem_t problem;
 691         int reset = 0, force_fsck = 0;
 692         int retval;
 693
 694         /* If we don't have any journal features, don't do anything more */
 695         if (!(sb->s_feature_compat & EXT3_FEATURE_COMPAT_HAS_JOURNAL) &&
 696             !recover && sb->s_journal_inum == 0 && sb->s_journal_dev == 0 &&
 697             uuid_is_null(sb->s_journal_uuid))
 698                 return 0;
 699
 700         clear_problem_context(&pctx);
 701         pctx.num = sb->s_journal_inum;
 702
 703         retval = e2fsck_get_journal(ctx, &journal);
 704         if (retval) {
 705                 if ((retval == EXT2_ET_BAD_INODE_NUM) ||
 706                     (retval == EXT2_ET_BAD_BLOCK_NUM) ||
 707                     (retval == EXT2_ET_JOURNAL_TOO_SMALL) ||
 708                     (retval == EXT2_ET_NO_JOURNAL))
 709                         return e2fsck_journal_fix_bad_inode(ctx, &pctx);
 710                 return retval;
 711         }
 712
 713         retval = e2fsck_journal_load(journal);
 714         if (retval) {
 715                 if ((retval == EXT2_ET_CORRUPT_SUPERBLOCK) ||
 716                     ((retval == EXT2_ET_UNSUPP_FEATURE) &&
 717                     (!fix_problem(ctx, PR_0_JOURNAL_UNSUPP_INCOMPAT,
 718                                   &pctx))) ||
 719                     ((retval == EXT2_ET_RO_UNSUPP_FEATURE) &&
 720                     (!fix_problem(ctx, PR_0_JOURNAL_UNSUPP_ROCOMPAT,
 721                                   &pctx))) ||
 722                     ((retval == EXT2_ET_JOURNAL_UNSUPP_VERSION) &&
 723                     (!fix_problem(ctx, PR_0_JOURNAL_UNSUPP_VERSION, &pctx))))
 724                         retval = e2fsck_journal_fix_corrupt_super(ctx, journal,
 725                                                                   &pctx);
 726                 e2fsck_journal_release(ctx, journal, 0, 1);
 727                 return retval;
 728         }
 729
 730         /*
 731          * We want to make the flags consistent here.  We will not leave with
 732          * needs_recovery set but has_journal clear.  We can't get in a loop
 733          * with -y, -n, or -p, only if a user isn't making up their mind.
 734          */
 735 no_has_journal:
 736         if (!(sb->s_feature_compat & EXT3_FEATURE_COMPAT_HAS_JOURNAL)) {
 737                 recover = sb->s_feature_incompat & EXT3_FEATURE_INCOMPAT_RECOVER;
 738                 pctx.str = "inode";
 739                 if (fix_problem(ctx, PR_0_JOURNAL_HAS_JOURNAL, &pctx)) {
 740                         if (recover &&
 741                             !fix_problem(ctx, PR_0_JOURNAL_RECOVER_SET, &pctx))
 742                                 goto no_has_journal;
 743                         /*
 744                          * Need a full fsck if we are releasing a
 745                          * journal stored on a reserved inode.
 746                          */
 747                         force_fsck = recover ||
 748                                 (sb->s_journal_inum < EXT2_FIRST_INODE(sb));
 749                         /* Clear all of the journal fields */
 750                         sb->s_journal_inum = 0;
 751                         sb->s_journal_dev = 0;
 752                         memset(sb->s_journal_uuid, 0,
 753                                sizeof(sb->s_journal_uuid));
 754                         e2fsck_clear_recover(ctx, force_fsck);
 755                 } else if (!(ctx->options & E2F_OPT_READONLY)) {
 756                         sb->s_feature_compat |= EXT3_FEATURE_COMPAT_HAS_JOURNAL;
 757                         ctx->fs->flags &= ~EXT2_FLAG_MASTER_SB_ONLY;
 758                         ext2fs_mark_super_dirty(ctx->fs);
 759                 }
 760         }
 761
 762         if (sb->s_feature_compat & EXT3_FEATURE_COMPAT_HAS_JOURNAL &&
 763             !(sb->s_feature_incompat & EXT3_FEATURE_INCOMPAT_RECOVER) &&
 764             journal->j_superblock->s_start != 0) {
 765                 /* Print status information */
 766                 fix_problem(ctx, PR_0_JOURNAL_RECOVERY_CLEAR, &pctx);
 767                 if (ctx->superblock)
 768                         problem = PR_0_JOURNAL_RUN_DEFAULT;
 769                 else
 770                         problem = PR_0_JOURNAL_RUN;
 771                 if (fix_problem(ctx, problem, &pctx)) {
 772                         ctx->options |= E2F_OPT_FORCE;
 773                         sb->s_feature_incompat |=
 774                                 EXT3_FEATURE_INCOMPAT_RECOVER;
 775                         ext2fs_mark_super_dirty(ctx->fs);
 776                 } else if (fix_problem(ctx,
 777                                        PR_0_JOURNAL_RESET_JOURNAL, &pctx)) {
 778                         reset = 1;
 779                         sb->s_state &= ~EXT2_VALID_FS;
 780                         ext2fs_mark_super_dirty(ctx->fs);
 781                 }
 782                 /*
 783                  * If the user answers no to the above question, we
 784                  * ignore the fact that journal apparently has data;
 785                  * accidentally replaying over valid data would be far
 786                  * worse than skipping a questionable recovery.
 787                  *
 788                  * XXX should we abort with a fatal error here?  What
 789                  * will the ext3 kernel code do if a filesystem with
 790                  * !NEEDS_RECOVERY but with a non-zero
 791                  * journal->j_superblock->s_start is mounted?
 792                  */
 793         }
 794
 795         e2fsck_journal_release(ctx, journal, reset, 0);
 796         return retval;
 797 }
 798
 799 static errcode_t recover_ext3_journal(e2fsck_t ctx)
 800 {
 801         journal_t *journal;
 802         int retval;
 803
 804         journal_init_revoke_caches();
 805         retval = e2fsck_get_journal(ctx, &journal);
 806         if (retval)
 807                 return retval;
 808
 809         retval = e2fsck_journal_load(journal);
 810         if (retval)
 811                 goto errout;
 812
 813         retval = journal_init_revoke(journal, 1024);
 814         if (retval)
 815                 goto errout;
 816
 817         retval = -journal_recover(journal);
 818         if (retval)
 819                 goto errout;
 820
 821         if (journal->j_superblock->s_errno) {
 822                 ctx->fs->super->s_state |= EXT2_ERROR_FS;
 823                 ext2fs_mark_super_dirty(ctx->fs);
 824                 journal->j_superblock->s_errno = 0;
 825                 mark_buffer_dirty(journal->j_sb_buffer);
 826         }
 827
 828 errout:
 829         journal_destroy_revoke(journal);
 830         journal_destroy_revoke_caches();
 831         e2fsck_journal_release(ctx, journal, 1, 0);
 832         return retval;
 833 }
 834
 835 int e2fsck_run_ext3_journal(e2fsck_t ctx)
 836 {
 837         io_manager io_ptr = ctx->fs->io->manager;
 838         int blocksize = ctx->fs->blocksize;
 839         errcode_t       retval, recover_retval;
 840
 841         printf(_("%s: recovering journal\n"), ctx->device_name);
 842         if (ctx->options & E2F_OPT_READONLY) {
 843                 printf(_("%s: won't do journal recovery while read-only\n"),
 844                        ctx->device_name);
 845                 return EXT2_ET_FILE_RO;
 846         }
 847
 848         if (ctx->fs->flags & EXT2_FLAG_DIRTY)
 849                 ext2fs_flush(ctx->fs);  /* Force out any modifications */
 850
 851         recover_retval = recover_ext3_journal(ctx);
 852
 853         /*
 854          * Reload the filesystem context to get up-to-date data from disk
 855          * because journal recovery will change the filesystem under us.
 856          */
 857         ext2fs_close(ctx->fs);
 858         retval = ext2fs_open(ctx->filesystem_name, EXT2_FLAG_RW,
 859                              ctx->superblock, blocksize, io_ptr,
 860                              &ctx->fs);
 861
 862         if (retval) {
 863                 com_err(ctx->program_name, retval,
 864                         _("while trying to re-open %s"),
 865                         ctx->device_name);
 866                 fatal_error(ctx, 0);
 867         }
 868         ctx->fs->priv_data = ctx;
 869         ctx->fs->now = ctx->now;
 870         ctx->fs->flags |= EXT2_FLAG_MASTER_SB_ONLY;
 871
 872         /* Set the superblock flags */
 873         e2fsck_clear_recover(ctx, recover_retval);
 874         return recover_retval;
 875 }
 876
 877 /*
 878  * This function will move the journal inode from a visible file in
 879  * the filesystem directory hierarchy to the reserved inode if necessary.
 880  */
 881 static const char * const journal_names[] = {
 882         ".journal", "journal", ".journal.dat", "journal.dat", 0 };
 883
 884 void e2fsck_move_ext3_journal(e2fsck_t ctx)
 885 {
 886         struct ext2_super_block *sb = ctx->fs->super;
 887         struct problem_context  pctx;
 888         struct ext2_inode       inode;
 889         ext2_filsys             fs = ctx->fs;
 890         ext2_ino_t              ino;
 891         errcode_t               retval;
 892         const char * const *    cpp;
 893         int                     group, mount_flags;
 894
 895         clear_problem_context(&pctx);
 896
 897         /*
 898          * If the filesystem is opened read-only, or there is no
 899          * journal, then do nothing.
 900          */
 901         if ((ctx->options & E2F_OPT_READONLY) ||
 902             (sb->s_journal_inum == 0) ||
 903             !(sb->s_feature_compat & EXT3_FEATURE_COMPAT_HAS_JOURNAL))
 904                 return;
 905
 906         /*
 907          * Read in the journal inode
 908          */
 909         if (ext2fs_read_inode(fs, sb->s_journal_inum, &inode) != 0)
 910                 return;
 911
 912         /*
 913          * If it's necessary to backup the journal inode, do so.
 914          */
 915         if ((sb->s_jnl_backup_type == 0) ||
 916             ((sb->s_jnl_backup_type == EXT3_JNL_BACKUP_BLOCKS) &&
 917              memcmp(inode.i_block, sb->s_jnl_blocks, EXT2_N_BLOCKS*4))) {
 918                 if (fix_problem(ctx, PR_0_BACKUP_JNL, &pctx)) {
 919                         memcpy(sb->s_jnl_blocks, inode.i_block,
 920                                EXT2_N_BLOCKS*4);
 921                         sb->s_jnl_blocks[16] = inode.i_size;
 922                         sb->s_jnl_backup_type = EXT3_JNL_BACKUP_BLOCKS;
 923                         ext2fs_mark_super_dirty(fs);
 924                         fs->flags &= ~EXT2_FLAG_MASTER_SB_ONLY;
 925                 }
 926         }
 927
 928         /*
 929          * If the journal is already the hidden inode, then do nothing
 930          */
 931         if (sb->s_journal_inum == EXT2_JOURNAL_INO)
 932                 return;
 933
 934         /*
 935          * The journal inode had better have only one link and not be readable.
 936          */
 937         if (inode.i_links_count != 1)
 938                 return;
 939
 940         /*
 941          * If the filesystem is mounted, or we can't tell whether
 942          * or not it's mounted, do nothing.
 943          */
 944         retval = ext2fs_check_if_mounted(ctx->filesystem_name, &mount_flags);
 945         if (retval || (mount_flags & EXT2_MF_MOUNTED))
 946                 return;
 947
 948         /*
 949          * If we can't find the name of the journal inode, then do
 950          * nothing.
 951          */
 952         for (cpp = journal_names; *cpp; cpp++) {
 953                 retval = ext2fs_lookup(fs, EXT2_ROOT_INO, *cpp,
 954                                        strlen(*cpp), 0, &ino);
 955                 if ((retval == 0) && (ino == sb->s_journal_inum))
 956                         break;
 957         }
 958         if (*cpp == 0)
 959                 return;
 960
 961         /* We need the inode bitmap to be loaded */
 962         retval = ext2fs_read_bitmaps(fs);
 963         if (retval)
 964                 return;
 965
 966         pctx.str = *cpp;
 967         if (!fix_problem(ctx, PR_0_MOVE_JOURNAL, &pctx))
 968                 return;
 969
 970         /*
 971          * OK, we've done all the checks, let's actually move the
 972          * journal inode.  Errors at this point mean we need to force
 973          * an ext2 filesystem check.
 974          */
 975         if ((retval = ext2fs_unlink(fs, EXT2_ROOT_INO, *cpp, ino, 0)) != 0)
 976                 goto err_out;
 977         if ((retval = ext2fs_write_inode(fs, EXT2_JOURNAL_INO, &inode)) != 0)
 978                 goto err_out;
 979         sb->s_journal_inum = EXT2_JOURNAL_INO;
 980         ext2fs_mark_super_dirty(fs);
 981         fs->flags &= ~EXT2_FLAG_MASTER_SB_ONLY;
 982         inode.i_links_count = 0;
 983         inode.i_dtime = ctx->now;
 984         if ((retval = ext2fs_write_inode(fs, ino, &inode)) != 0)
 985                 goto err_out;
 986
 987         group = ext2fs_group_of_ino(fs, ino);
 988         ext2fs_unmark_inode_bitmap(fs->inode_map, ino);
 989         ext2fs_mark_ib_dirty(fs);
 990         fs->group_desc[group].bg_free_inodes_count++;
 991         fs->super->s_free_inodes_count++;
 992         return;
 993
 994 err_out:
 995         pctx.errcode = retval;
 996         fix_problem(ctx, PR_0_ERR_MOVE_JOURNAL, &pctx);
 997         fs->super->s_state &= ~EXT2_VALID_FS;
 998         ext2fs_mark_super_dirty(fs);
 999         return;
1000 }
1001
1002 /*
1003  * This function makes sure the superblock hint for the external
1004  * journal is correct.
1005  */
1006 int e2fsck_fix_ext3_journal_hint(e2fsck_t ctx)
1007 {
1008         struct ext2_super_block *sb = ctx->fs->super;
1009         struct problem_context pctx;
1010         char uuid[37], *journal_name;
1011         struct stat st;
1012
1013         if (!(sb->s_feature_compat & EXT3_FEATURE_COMPAT_HAS_JOURNAL) ||
1014             uuid_is_null(sb->s_journal_uuid))
1015                 return 0;
1016
1017         uuid_unparse(sb->s_journal_uuid, uuid);
1018         journal_name = blkid_get_devname(ctx->blkid, "UUID", uuid);
1019         if (!journal_name)
1020                 return 0;
1021
1022         if (stat(journal_name, &st) < 0)
1023                 return 0;
1024
1025         if (st.st_rdev != sb->s_journal_dev) {
1026                 clear_problem_context(&pctx);
1027                 pctx.num = st.st_rdev;
1028                 if (fix_problem(ctx, PR_0_EXTERNAL_JOURNAL_HINT, &pctx)) {
1029                         sb->s_journal_dev = st.st_rdev;
1030                         ext2fs_mark_super_dirty(ctx->fs);
1031                 }
1032         }
1033
1034         free(journal_name);
1035         return 0;
1036 }