logdump.c revision 65f0aab98b20b5994a726ab90d355248bcddfffd 
1/*
2 * logdump.c --- dump the contents of the journal out to a file
3 *
4 * Authro: Stephen C. Tweedie, 2001  <sct@redhat.com>
5 * Copyright (C) 2001 Red Hat, Inc.
6 * Based on portions  Copyright (C) 1994 Theodore Ts'o.
7 *
8 * This file may be redistributed under the terms of the GNU Public
9 * License.
10 */
11
12#include <stdio.h>
13#include <unistd.h>
14#include <stdlib.h>
15#include <ctype.h>
16#include <string.h>
17#include <time.h>
18#ifdef HAVE_ERRNO_H
19#include <errno.h>
20#endif
21#include <sys/types.h>
22#include <sys/stat.h>
23#include <fcntl.h>
24#include <utime.h>
25#ifdef HAVE_GETOPT_H
26#include <getopt.h>
27#else
28extern int optind;
29extern char *optarg;
30#endif
31
32#include "debugfs.h"
33#include "blkid/blkid.h"
34#include "jfs_user.h"
35#include <uuid/uuid.h>
36
37enum journal_location {JOURNAL_IS_INTERNAL, JOURNAL_IS_EXTERNAL};
38
39#define ANY_BLOCK ((blk_t) -1)
40
41int		dump_all, dump_contents, dump_descriptors;
42blk_t		block_to_dump, bitmap_to_dump, inode_block_to_dump;
43unsigned int	group_to_dump, inode_offset_to_dump;
44ext2_ino_t	inode_to_dump;
45
46struct journal_source
47{
48	enum journal_location where;
49	int fd;
50	ext2_file_t file;
51};
52
53static void dump_journal(char *, FILE *, struct journal_source *);
54
55static void dump_descriptor_block(FILE *, struct journal_source *,
56				  char *, journal_superblock_t *,
57				  unsigned int *, int, tid_t);
58
59static void dump_revoke_block(FILE *, char *, journal_superblock_t *,
60				  unsigned int, int, tid_t);
61
62static void dump_metadata_block(FILE *, struct journal_source *,
63				journal_superblock_t*,
64				unsigned int, unsigned int, unsigned int,
65				int, tid_t);
66
67static void do_hexdump (FILE *, char *, int);
68
69#define WRAP(jsb, blocknr)					\
70	if (blocknr >= be32_to_cpu((jsb)->s_maxlen))		\
71		blocknr -= (be32_to_cpu((jsb)->s_maxlen) -	\
72			    be32_to_cpu((jsb)->s_first));
73
74void do_logdump(int argc, char **argv)
75{
76	int		c;
77	int		retval;
78	char		*out_fn;
79	FILE		*out_file;
80
81	char		*inode_spec = NULL;
82	char		*journal_fn = NULL;
83	int		journal_fd = 0;
84	int		use_sb = 0;
85	ext2_ino_t	journal_inum;
86	struct ext2_inode journal_inode;
87	ext2_file_t 	journal_file;
88	char		*tmp;
89	struct journal_source journal_source;
90	struct ext2_super_block *es = NULL;
91
92	journal_source.where = JOURNAL_IS_INTERNAL;
93	journal_source.fd = 0;
94	journal_source.file = 0;
95	dump_all = 0;
96	dump_contents = 0;
97	dump_descriptors = 1;
98	block_to_dump = ANY_BLOCK;
99	bitmap_to_dump = -1;
100	inode_block_to_dump = ANY_BLOCK;
101	inode_to_dump = -1;
102
103	reset_getopt();
104	while ((c = getopt (argc, argv, "ab:ci:f:s")) != EOF) {
105		switch (c) {
106		case 'a':
107			dump_all++;
108			break;
109		case 'b':
110			block_to_dump = strtoul(optarg, &tmp, 0);
111			if (*tmp) {
112				com_err(argv[0], 0,
113					"Bad block number - %s", optarg);
114				return;
115			}
116			dump_descriptors = 0;
117			break;
118		case 'c':
119			dump_contents++;
120			break;
121		case 'f':
122			journal_fn = optarg;
123			break;
124		case 'i':
125			inode_spec = optarg;
126			dump_descriptors = 0;
127			break;
128		case 's':
129			use_sb++;
130			break;
131		default:
132			goto print_usage;
133		}
134	}
135	if (optind != argc && optind != argc-1) {
136		goto print_usage;
137	}
138
139	if (current_fs)
140		es = current_fs->super;
141
142	if (inode_spec) {
143		int inode_group, group_offset, inodes_per_block;
144
145		if (check_fs_open(argv[0]))
146			return;
147
148		inode_to_dump = string_to_inode(inode_spec);
149		if (!inode_to_dump)
150			return;
151
152		inode_group = ((inode_to_dump - 1)
153			       / es->s_inodes_per_group);
154		group_offset = ((inode_to_dump - 1)
155				% es->s_inodes_per_group);
156		inodes_per_block = (current_fs->blocksize
157				    / sizeof(struct ext2_inode));
158
159		inode_block_to_dump =
160			current_fs->group_desc[inode_group].bg_inode_table +
161			(group_offset / inodes_per_block);
162		inode_offset_to_dump = ((group_offset % inodes_per_block)
163					* sizeof(struct ext2_inode));
164		printf("Inode %u is at group %u, block %u, offset %u\n",
165		       inode_to_dump, inode_group,
166		       inode_block_to_dump, inode_offset_to_dump);
167	}
168
169	if (optind == argc) {
170		out_file = stdout;
171	} else {
172		out_fn = argv[optind];
173		out_file = fopen(out_fn, "w");
174		if (!out_file) {
175			com_err(argv[0], errno, "while opening %s for logdump",
176				out_fn);
177			goto errout;
178		}
179	}
180
181	if (block_to_dump != ANY_BLOCK && current_fs != NULL) {
182		group_to_dump = ((block_to_dump -
183				  es->s_first_data_block)
184				 / es->s_blocks_per_group);
185		bitmap_to_dump = current_fs->group_desc[group_to_dump].bg_block_bitmap;
186	}
187
188	if (!journal_fn && check_fs_open(argv[0]))
189		goto errout;
190
191	if (journal_fn) {
192		/* Set up to read journal from a regular file somewhere */
193		journal_fd = open(journal_fn, O_RDONLY, 0);
194		if (journal_fd < 0) {
195			com_err(argv[0], errno, "while opening %s for logdump",
196				journal_fn);
197			goto errout;
198		}
199
200		journal_source.where = JOURNAL_IS_EXTERNAL;
201		journal_source.fd = journal_fd;
202	} else if ((journal_inum = es->s_journal_inum)) {
203		if (use_sb) {
204			if (es->s_jnl_backup_type != EXT3_JNL_BACKUP_BLOCKS) {
205				com_err(argv[0], 0,
206					"no journal backup in super block\n");
207				goto errout;
208			}
209			memset(&journal_inode, 0, sizeof(struct ext2_inode));
210			memcpy(&journal_inode.i_block[0], es->s_jnl_blocks,
211			       EXT2_N_BLOCKS*4);
212			journal_inode.i_size = es->s_jnl_blocks[16];
213			journal_inode.i_links_count = 1;
214			journal_inode.i_mode = LINUX_S_IFREG | 0600;
215		} else {
216			if (debugfs_read_inode(journal_inum, &journal_inode,
217					       argv[0]))
218				goto errout;
219		}
220
221		retval = ext2fs_file_open2(current_fs, journal_inum,
222					   &journal_inode, 0, &journal_file);
223		if (retval) {
224			com_err(argv[0], retval, "while opening ext2 file");
225			goto errout;
226		}
227		journal_source.where = JOURNAL_IS_INTERNAL;
228		journal_source.file = journal_file;
229	} else {
230		char uuid[37];
231
232		uuid_unparse(es->s_journal_uuid, uuid);
233		journal_fn = blkid_get_devname(NULL, "UUID", uuid);
234		if (!journal_fn)
235				journal_fn = blkid_devno_to_devname(es->s_journal_dev);
236		if (!journal_fn) {
237			com_err(argv[0], 0, "filesystem has no journal");
238			goto errout;
239		}
240		journal_fd = open(journal_fn, O_RDONLY, 0);
241		if (journal_fd < 0) {
242			com_err(argv[0], errno, "while opening %s for logdump",
243				journal_fn);
244			free(journal_fn);
245			goto errout;
246		}
247		fprintf(out_file, "Using external journal found at %s\n",
248			journal_fn);
249		free(journal_fn);
250		journal_source.where = JOURNAL_IS_EXTERNAL;
251		journal_source.fd = journal_fd;
252	}
253
254	dump_journal(argv[0], out_file, &journal_source);
255
256	if (journal_source.where == JOURNAL_IS_INTERNAL)
257		ext2fs_file_close(journal_file);
258	else
259		close(journal_fd);
260
261errout:
262	if (out_file && (out_file != stdout))
263		fclose(out_file);
264
265	return;
266
267print_usage:
268	fprintf(stderr, "%s: Usage: logdump [-acs] [-b<block>] [-i<filespec>]\n\t"
269		"[-f<journal_file>] [output_file]\n", argv[0]);
270}
271
272
273static int read_journal_block(const char *cmd, struct journal_source *source,
274			      off_t offset, char *buf, int size,
275			      unsigned int *got)
276{
277	int retval;
278
279	if (source->where == JOURNAL_IS_EXTERNAL) {
280		if (lseek(source->fd, offset, SEEK_SET) < 0) {
281			retval = errno;
282			com_err(cmd, retval, "while seeking in reading journal");
283			return retval;
284		}
285		retval = read(source->fd, buf, size);
286		if (retval >= 0) {
287			*got = retval;
288			retval = 0;
289		} else
290			retval = errno;
291	} else {
292		retval = ext2fs_file_lseek(source->file, offset,
293					   EXT2_SEEK_SET, NULL);
294		if (retval) {
295			com_err(cmd, retval, "while seeking in reading journal");
296			return retval;
297		}
298
299		retval = ext2fs_file_read(source->file, buf, size, got);
300	}
301
302	if (retval)
303		com_err(cmd, retval, "while reading journal");
304	else if (*got != (unsigned int) size) {
305		com_err(cmd, 0, "short read (read %d, expected %d) "
306			"while reading journal", *got, size);
307		retval = -1;
308	}
309
310	return retval;
311}
312
313static const char *type_to_name(int btype)
314{
315	switch (btype) {
316	case JFS_DESCRIPTOR_BLOCK:
317		return "descriptor block";
318	case JFS_COMMIT_BLOCK:
319		return "commit block";
320	case JFS_SUPERBLOCK_V1:
321		return "V1 superblock";
322	case JFS_SUPERBLOCK_V2:
323		return "V2 superblock";
324	case JFS_REVOKE_BLOCK:
325		return "revoke table";
326	}
327	return "unrecognised type";
328}
329
330
331static void dump_journal(char *cmdname, FILE *out_file,
332			 struct journal_source *source)
333{
334	struct ext2_super_block *sb;
335	char			jsb_buffer[1024];
336	char			buf[8192];
337	journal_superblock_t	*jsb;
338	unsigned int		blocksize = 1024;
339	unsigned int		got;
340	int			retval;
341	__u32			magic, sequence, blocktype;
342	journal_header_t	*header;
343
344	tid_t			transaction;
345	unsigned int		blocknr = 0;
346
347	/* First, check to see if there's an ext2 superblock header */
348	retval = read_journal_block(cmdname, source, 0,
349				    buf, 2048, &got);
350	if (retval)
351		return;
352
353	jsb = (journal_superblock_t *) buf;
354	sb = (struct ext2_super_block *) (buf+1024);
355#ifdef WORDS_BIGENDIAN
356	if (sb->s_magic == ext2fs_swab16(EXT2_SUPER_MAGIC))
357		ext2fs_swap_super(sb);
358#endif
359
360	if ((be32_to_cpu(jsb->s_header.h_magic) != JFS_MAGIC_NUMBER) &&
361	    (sb->s_magic == EXT2_SUPER_MAGIC) &&
362	    (sb->s_feature_incompat & EXT3_FEATURE_INCOMPAT_JOURNAL_DEV)) {
363		blocksize = EXT2_BLOCK_SIZE(sb);
364		blocknr = (blocksize == 1024) ? 2 : 1;
365		uuid_unparse(sb->s_uuid, jsb_buffer);
366		fprintf(out_file, "Ext2 superblock header found.\n");
367		if (dump_all) {
368			fprintf(out_file, "\tuuid=%s\n", jsb_buffer);
369			fprintf(out_file, "\tblocksize=%d\n", blocksize);
370			fprintf(out_file, "\tjournal data size %lu\n",
371				(unsigned long) sb->s_blocks_count);
372		}
373	}
374
375	/* Next, read the journal superblock */
376
377	retval = read_journal_block(cmdname, source, blocknr*blocksize,
378				    jsb_buffer, 1024, &got);
379	if (retval)
380		return;
381
382	jsb = (journal_superblock_t *) jsb_buffer;
383	if (be32_to_cpu(jsb->s_header.h_magic) != JFS_MAGIC_NUMBER) {
384		fprintf(out_file,
385			"Journal superblock magic number invalid!\n");
386		return;
387	}
388	blocksize = be32_to_cpu(jsb->s_blocksize);
389	transaction = be32_to_cpu(jsb->s_sequence);
390	blocknr = be32_to_cpu(jsb->s_start);
391
392	fprintf(out_file, "Journal starts at block %u, transaction %u\n",
393		blocknr, transaction);
394
395	if (!blocknr)
396		/* Empty journal, nothing to do. */
397		return;
398
399	while (1) {
400		retval = read_journal_block(cmdname, source,
401					    blocknr*blocksize, buf,
402					    blocksize, &got);
403		if (retval || got != blocksize)
404			return;
405
406		header = (journal_header_t *) buf;
407
408		magic = be32_to_cpu(header->h_magic);
409		sequence = be32_to_cpu(header->h_sequence);
410		blocktype = be32_to_cpu(header->h_blocktype);
411
412		if (magic != JFS_MAGIC_NUMBER) {
413			fprintf (out_file, "No magic number at block %u: "
414				 "end of journal.\n", blocknr);
415			return;
416		}
417
418		if (sequence != transaction) {
419			fprintf (out_file, "Found sequence %u (not %u) at "
420				 "block %u: end of journal.\n",
421				 sequence, transaction, blocknr);
422			return;
423		}
424
425		if (dump_descriptors) {
426			fprintf (out_file, "Found expected sequence %u, "
427				 "type %u (%s) at block %u\n",
428				 sequence, blocktype,
429				 type_to_name(blocktype), blocknr);
430		}
431
432		switch (blocktype) {
433		case JFS_DESCRIPTOR_BLOCK:
434			dump_descriptor_block(out_file, source, buf, jsb,
435					      &blocknr, blocksize,
436					      transaction);
437			continue;
438
439		case JFS_COMMIT_BLOCK:
440			transaction++;
441			blocknr++;
442			WRAP(jsb, blocknr);
443			continue;
444
445		case JFS_REVOKE_BLOCK:
446			dump_revoke_block(out_file, buf, jsb,
447					  blocknr, blocksize,
448					  transaction);
449			blocknr++;
450			WRAP(jsb, blocknr);
451			continue;
452
453		default:
454			fprintf (out_file, "Unexpected block type %u at "
455				 "block %u.\n", blocktype, blocknr);
456			return;
457		}
458	}
459}
460
461
462static void dump_descriptor_block(FILE *out_file,
463				  struct journal_source *source,
464				  char *buf,
465				  journal_superblock_t *jsb,
466				  unsigned int *blockp, int blocksize,
467				  tid_t transaction)
468{
469	int			offset, tag_size = JBD_TAG_SIZE32;
470	char			*tagp;
471	journal_block_tag_t	*tag;
472	unsigned int		blocknr;
473	__u32			tag_block;
474	__u32			tag_flags;
475
476	if (be32_to_cpu(jsb->s_feature_incompat) & JFS_FEATURE_INCOMPAT_64BIT)
477		tag_size = JBD_TAG_SIZE64;
478
479	offset = sizeof(journal_header_t);
480	blocknr = *blockp;
481
482	if (dump_all)
483		fprintf(out_file, "Dumping descriptor block, sequence %u, at "
484			"block %u:\n", transaction, blocknr);
485
486	++blocknr;
487	WRAP(jsb, blocknr);
488
489	do {
490		/* Work out the location of the current tag, and skip to
491		 * the next one... */
492		tagp = &buf[offset];
493		tag = (journal_block_tag_t *) tagp;
494		offset += tag_size;
495
496		/* ... and if we have gone too far, then we've reached the
497		   end of this block. */
498		if (offset > blocksize)
499			break;
500
501		tag_block = be32_to_cpu(tag->t_blocknr);
502		tag_flags = be32_to_cpu(tag->t_flags);
503
504		if (!(tag_flags & JFS_FLAG_SAME_UUID))
505			offset += 16;
506
507		dump_metadata_block(out_file, source, jsb,
508				    blocknr, tag_block, tag_flags, blocksize,
509				    transaction);
510
511		++blocknr;
512		WRAP(jsb, blocknr);
513
514	} while (!(tag_flags & JFS_FLAG_LAST_TAG));
515
516	*blockp = blocknr;
517}
518
519
520static void dump_revoke_block(FILE *out_file, char *buf,
521			      journal_superblock_t *jsb EXT2FS_ATTR((unused)),
522			      unsigned int blocknr,
523			      int blocksize EXT2FS_ATTR((unused)),
524			      tid_t transaction)
525{
526	int			offset, max;
527	journal_revoke_header_t *header;
528	unsigned int		*entry, rblock;
529
530	if (dump_all)
531		fprintf(out_file, "Dumping revoke block, sequence %u, at "
532			"block %u:\n", transaction, blocknr);
533
534	header = (journal_revoke_header_t *) buf;
535	offset = sizeof(journal_revoke_header_t);
536	max = be32_to_cpu(header->r_count);
537
538	while (offset < max) {
539		entry = (unsigned int *) (buf + offset);
540		rblock = be32_to_cpu(*entry);
541		if (dump_all || rblock == block_to_dump) {
542			fprintf(out_file, "  Revoke FS block %u", rblock);
543			if (dump_all)
544				fprintf(out_file, "\n");
545			else
546				fprintf(out_file," at block %u, sequence %u\n",
547					blocknr, transaction);
548		}
549		offset += 4;
550	}
551}
552
553
554static void show_extent(FILE *out_file, int start_extent, int end_extent,
555			__u32 first_block)
556{
557	if (start_extent >= 0 && first_block != 0)
558		fprintf(out_file, "(%d+%u): %u ",
559			start_extent, end_extent-start_extent, first_block);
560}
561
562static void show_indirect(FILE *out_file, const char *name, __u32 where)
563{
564	if (where)
565		fprintf(out_file, "(%s): %u ", name, where);
566}
567
568
569static void dump_metadata_block(FILE *out_file, struct journal_source *source,
570				journal_superblock_t *jsb EXT2FS_ATTR((unused)),
571				unsigned int log_blocknr,
572				unsigned int fs_blocknr,
573				unsigned int log_tag_flags,
574				int blocksize,
575				tid_t transaction)
576{
577	unsigned int 	got;
578	int		retval;
579	char 		buf[8192];
580
581	if (!(dump_all
582	      || (fs_blocknr == block_to_dump)
583	      || (fs_blocknr == inode_block_to_dump)
584	      || (fs_blocknr == bitmap_to_dump)))
585		return;
586
587	fprintf(out_file, "  FS block %u logged at ", fs_blocknr);
588	if (!dump_all)
589		fprintf(out_file, "sequence %u, ", transaction);
590	fprintf(out_file, "journal block %u (flags 0x%x)\n", log_blocknr,
591		log_tag_flags);
592
593	/* There are two major special cases to parse:
594	 *
595	 * If this block is a block
596	 * bitmap block, we need to give it special treatment so that we
597	 * can log any allocates and deallocates which affect the
598	 * block_to_dump query block.
599	 *
600	 * If the block is an inode block for the inode being searched
601	 * for, then we need to dump the contents of that inode
602	 * structure symbolically.
603	 */
604
605	if (!(dump_contents && dump_all)
606	    && fs_blocknr != block_to_dump
607	    && fs_blocknr != bitmap_to_dump
608	    && fs_blocknr != inode_block_to_dump)
609		return;
610
611	retval = read_journal_block("logdump", source,
612				    blocksize * log_blocknr,
613				    buf, blocksize, &got);
614	if (retval)
615		return;
616
617	if (fs_blocknr == bitmap_to_dump) {
618		struct ext2_super_block *super;
619		int offset;
620
621		super = current_fs->super;
622		offset = ((block_to_dump - super->s_first_data_block) %
623			  super->s_blocks_per_group);
624
625		fprintf(out_file, "    (block bitmap for block %u: "
626			"block is %s)\n",
627			block_to_dump,
628			ext2fs_test_bit(offset, buf) ? "SET" : "CLEAR");
629	}
630
631	if (fs_blocknr == inode_block_to_dump) {
632		struct ext2_inode *inode;
633		int first, prev, this, start_extent, i;
634
635		fprintf(out_file, "    (inode block for inode %u):\n",
636			inode_to_dump);
637
638		inode = (struct ext2_inode *) (buf + inode_offset_to_dump);
639		internal_dump_inode(out_file, "    ", inode_to_dump, inode, 0);
640
641		/* Dump out the direct/indirect blocks here:
642		 * internal_dump_inode can only dump them from the main
643		 * on-disk inode, not from the journaled copy of the
644		 * inode. */
645
646		fprintf (out_file, "    Blocks:  ");
647		first = prev = start_extent = -1;
648
649		for (i=0; i<EXT2_NDIR_BLOCKS; i++) {
650			this = inode->i_block[i];
651			if (start_extent >= 0  && this == prev+1) {
652				prev = this;
653				continue;
654			} else {
655				show_extent(out_file, start_extent, i, first);
656				start_extent = i;
657				first = prev = this;
658			}
659		}
660		show_extent(out_file, start_extent, i, first);
661		show_indirect(out_file, "IND", inode->i_block[i++]);
662		show_indirect(out_file, "DIND", inode->i_block[i++]);
663		show_indirect(out_file, "TIND", inode->i_block[i++]);
664
665		fprintf(out_file, "\n");
666	}
667
668	if (dump_contents)
669		do_hexdump(out_file, buf, blocksize);
670
671}
672
673static void do_hexdump (FILE *out_file, char *buf, int blocksize)
674{
675	int i,j;
676	int *intp;
677	char *charp;
678	unsigned char c;
679
680	intp = (int *) buf;
681	charp = (char *) buf;
682
683	for (i=0; i<blocksize; i+=16) {
684		fprintf(out_file, "    %04x:  ", i);
685		for (j=0; j<16; j+=4)
686			fprintf(out_file, "%08x ", *intp++);
687		for (j=0; j<16; j++) {
688			c = *charp++;
689			if (c < ' ' || c >= 127)
690				c = '.';
691			fprintf(out_file, "%c", c);
692		}
693		fprintf(out_file, "\n");
694	}
695}
696
697