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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  */
journal_bmap(journal_t * journal,blk_t block,unsigned long * phys)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 
getblk(kdev_t kdev,blk_t blocknr,int blocksize)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 
sync_blockdev(kdev_t kdev)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 
ll_rw_block(int rw,int nr,struct buffer_head * bhp[])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 
mark_buffer_dirty(struct buffer_head * bh)146 void mark_buffer_dirty(struct buffer_head *bh)
147 {
148 	bh->b_dirty = 1;
149 }
150 
mark_buffer_clean(struct buffer_head * bh)151 static void mark_buffer_clean(struct buffer_head * bh)
152 {
153 	bh->b_dirty = 0;
154 }
155 
brelse(struct buffer_head * bh)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 
buffer_uptodate(struct buffer_head * bh)165 int buffer_uptodate(struct buffer_head *bh)
166 {
167 	return bh->b_uptodate;
168 }
169 
mark_buffer_uptodate(struct buffer_head * bh,int val)170 void mark_buffer_uptodate(struct buffer_head *bh, int val)
171 {
172 	bh->b_uptodate = val;
173 }
174 
wait_on_buffer(struct buffer_head * bh)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 
e2fsck_clear_recover(e2fsck_t ctx,int error)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 
process_journal_block(ext2_filsys fs,blk_t * block_nr,e2_blkcnt_t blockcnt,blk_t ref_block EXT2FS_ATTR ((unused)),int ref_offset EXT2FS_ATTR ((unused)),void * priv_data)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 
e2fsck_get_journal(e2fsck_t ctx,journal_t ** ret_journal)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 
e2fsck_journal_fix_bad_inode(e2fsck_t ctx,struct problem_context * pctx)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
clear_v2_journal_fields(journal_t * journal)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 
e2fsck_journal_load(journal_t * journal)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 
e2fsck_journal_reset_super(e2fsck_t ctx,journal_superblock_t * jsb,journal_t * journal)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 
e2fsck_journal_fix_corrupt_super(e2fsck_t ctx,journal_t * journal,struct problem_context * pctx)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 
e2fsck_journal_release(e2fsck_t ctx,journal_t * journal,int reset,int drop)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  */
e2fsck_check_ext3_journal(e2fsck_t ctx)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 
recover_ext3_journal(e2fsck_t ctx)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 
e2fsck_run_ext3_journal(e2fsck_t ctx)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 
e2fsck_move_ext3_journal(e2fsck_t ctx)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  */
e2fsck_fix_ext3_journal_hint(e2fsck_t ctx)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