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      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 }
   1037