logdump.c revision e1018eeaa3285cd0ca26986d929194c1b577d211 
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#ifdef HAVE_OPTRESET
32extern int optreset;		/* defined by BSD, but not others */
33#endif
34
35#include "debugfs.h"
36#include "jfs_user.h"
37#include <uuid/uuid.h>
38
39enum journal_location {JOURNAL_IS_INTERNAL, JOURNAL_IS_EXTERNAL};
40
41int		dump_all, dump_contents, dump_descriptors;
42unsigned int	block_to_dump, group_to_dump, bitmap_to_dump;
43unsigned int	inode_block_to_dump, inode_offset_to_dump, bitmap_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, int, tid_t);
65
66static void do_hexdump (FILE *, char *, int);
67
68#define WRAP(jsb, blocknr)					\
69	if (blocknr >= be32_to_cpu((jsb)->s_maxlen))		\
70		blocknr -= (be32_to_cpu((jsb)->s_maxlen) -	\
71			    be32_to_cpu((jsb)->s_first));
72
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	ext2_ino_t	journal_inum;
85	struct ext2_inode journal_inode;
86	ext2_file_t 	journal_file;
87
88	char		*tmp;
89
90	const char	*logdump_usage = ("Usage: logdump "
91					  "[-ac] [-b<block>] [-i<inode>] "
92					  "[-f<journal_file>] [output_file]");
93
94	struct journal_source journal_source;
95
96	optind = 0;
97#ifdef HAVE_OPTRESET
98	optreset = 1;		/* Makes BSD getopt happy */
99#endif
100	journal_source.where = 0;
101	journal_source.fd = 0;
102	journal_source.file = 0;
103	dump_all = 0;
104	dump_contents = 0;
105	dump_descriptors = 1;
106	block_to_dump = -1;
107	bitmap_to_dump = -1;
108	inode_block_to_dump = -1;
109	inode_to_dump = -1;
110
111	while ((c = getopt (argc, argv, "ab:ci:f:")) != EOF) {
112		switch (c) {
113		case 'a':
114			dump_all++;
115			break;
116		case 'b':
117			block_to_dump = strtoul(optarg, &tmp, 0);
118			if (*tmp) {
119				com_err(argv[0], 0,
120					"Bad block number - %s", optarg);
121				return;
122			}
123			dump_descriptors = 0;
124			break;
125		case 'c':
126			dump_contents++;
127			break;
128		case 'f':
129			journal_fn = optarg;
130			break;
131		case 'i':
132			inode_spec = optarg;
133			dump_descriptors = 0;
134			break;
135		default:
136			com_err(argv[0], 0, logdump_usage);
137			return;
138		}
139	}
140	if (optind != argc && optind != argc-1) {
141		com_err(argv[0], 0, logdump_usage);
142		return;
143	}
144
145	if (inode_spec) {
146		int inode_group, group_offset, inodes_per_block;
147
148		if (check_fs_open(argv[0]))
149			return;
150
151		inode_to_dump = string_to_inode(inode_spec);
152		if (!inode_to_dump)
153			return;
154
155		inode_group = ((inode_to_dump - 1)
156			       / current_fs->super->s_inodes_per_group);
157		group_offset = ((inode_to_dump - 1)
158				% current_fs->super->s_inodes_per_group);
159		inodes_per_block = (current_fs->blocksize
160				    / sizeof(struct ext2_inode));
161
162		inode_block_to_dump =
163			current_fs->group_desc[inode_group].bg_inode_table +
164			(group_offset / inodes_per_block);
165		inode_offset_to_dump = ((group_offset % inodes_per_block)
166					* sizeof(struct ext2_inode));
167		printf("Inode %u is at group %u, block %u, offset %u\n",
168		       inode_to_dump, inode_group,
169		       inode_block_to_dump, inode_offset_to_dump);
170	}
171
172	if (optind == argc) {
173		out_file = stdout;
174	} else {
175		out_fn = argv[optind];
176		out_file = fopen(out_fn, "w");
177		if (!out_file < 0) {
178			com_err(argv[0], errno, "while opening %s for logdump",
179				out_fn);
180			return;
181		}
182	}
183
184	if (block_to_dump != -1 && current_fs != NULL) {
185		group_to_dump = ((block_to_dump -
186				  current_fs->super->s_first_data_block)
187				 / current_fs->super->s_blocks_per_group);
188		bitmap_to_dump = current_fs->group_desc[group_to_dump].bg_block_bitmap;
189	}
190
191	if (!journal_fn && check_fs_open(argv[0]))
192		return;
193
194	if (journal_fn) {
195		/* Set up to read journal from a regular file somewhere */
196		journal_fd = open(journal_fn, O_RDONLY, 0);
197		if (journal_fd < 0) {
198			com_err(argv[0], errno, "while opening %s for logdump",
199				journal_fn);
200			return;
201		}
202
203		journal_source.where = JOURNAL_IS_EXTERNAL;
204		journal_source.fd = journal_fd;
205	} else if ((journal_inum = current_fs->super->s_journal_inum)) {
206		if (debugfs_read_inode(journal_inum, &journal_inode, argv[0]))
207			return;
208
209		retval = ext2fs_file_open(current_fs, journal_inum,
210					  0, &journal_file);
211		if (retval) {
212			com_err(argv[0], retval, "while opening ext2 file");
213			return;
214		}
215		journal_source.where = JOURNAL_IS_INTERNAL;
216		journal_source.file = journal_file;
217	} else if ((journal_fn =
218	    ext2fs_find_block_device(current_fs->super->s_journal_dev))) {
219		journal_fd = open(journal_fn, O_RDONLY, 0);
220		if (journal_fd < 0) {
221			com_err(argv[0], errno, "while opening %s for logdump",
222				journal_fn);
223			free(journal_fn);
224			return;
225		}
226		fprintf(out_file, "Using external journal found at %s\n",
227			journal_fn);
228		free(journal_fn);
229		journal_source.where = JOURNAL_IS_EXTERNAL;
230		journal_source.fd = journal_fd;
231	} else {
232		com_err(argv[0], 0, "filesystem has no journal");
233		return;
234	}
235
236	dump_journal(argv[0], out_file, &journal_source);
237
238	if (journal_source.where == JOURNAL_IS_INTERNAL)
239		ext2fs_file_close(journal_file);
240	else
241		close(journal_fd);
242
243	if (out_file != stdout)
244		fclose(out_file);
245
246	return;
247}
248
249
250static int read_journal_block(const char *cmd, struct journal_source *source,
251			      off_t offset, char *buf, int size,
252			      unsigned int *got)
253{
254	int retval;
255
256	if (source->where == JOURNAL_IS_EXTERNAL) {
257		if (lseek(source->fd, offset, SEEK_SET) < 0) {
258			retval = errno;
259			com_err(cmd, retval, "while seeking in reading journal");
260			return retval;
261		}
262		retval = read(source->fd, buf, size);
263		if (retval >= 0) {
264			*got = retval;
265			retval = 0;
266		} else
267			retval = errno;
268	} else {
269		retval = ext2fs_file_lseek(source->file, offset,
270					   EXT2_SEEK_SET, NULL);
271		if (retval) {
272			com_err(cmd, retval, "while seeking in reading journal");
273			return retval;
274		}
275
276		retval = ext2fs_file_read(source->file, buf, size, got);
277	}
278
279	if (retval)
280		com_err(cmd, retval, "while while reading journal");
281	else if (*got != size) {
282		com_err(cmd, 0, "short read (read %d, expected %d) while while reading journal", *got, size);
283		retval = -1;
284	}
285
286	return retval;
287}
288
289static const char *type_to_name(int btype)
290{
291	switch (btype) {
292	case JFS_DESCRIPTOR_BLOCK:
293		return "descriptor block";
294	case JFS_COMMIT_BLOCK:
295		return "commit block";
296	case JFS_SUPERBLOCK_V1:
297		return "V1 superblock";
298	case JFS_SUPERBLOCK_V2:
299		return "V2 superblock";
300	case JFS_REVOKE_BLOCK:
301		return "revoke table";
302	}
303	return "unrecognised type";
304}
305
306
307static void dump_journal(char *cmdname, FILE *out_file,
308			 struct journal_source *source)
309{
310	struct ext2_super_block *sb;
311	char			jsb_buffer[1024];
312	char			buf[8192];
313	journal_superblock_t	*jsb;
314	int			blocksize = 1024;
315	unsigned int		got;
316	int			retval;
317	__u32			magic, sequence, blocktype;
318	journal_header_t	*header;
319
320	tid_t			transaction;
321	unsigned int		blocknr = 0;
322
323	/* First, check to see if there's an ext2 superblock header */
324	retval = read_journal_block(cmdname, source, 0,
325				    buf, 2048, &got);
326	if (retval)
327		return;
328
329	jsb = (journal_superblock_t *) buf;
330	sb = (struct ext2_super_block *) (buf+1024);
331#ifdef ENABLE_SWAPFS
332	if (sb->s_magic == ext2fs_swab16(EXT2_SUPER_MAGIC))
333		ext2fs_swap_super(sb);
334#endif
335
336	if ((be32_to_cpu(jsb->s_header.h_magic) != JFS_MAGIC_NUMBER) &&
337	    (sb->s_magic == EXT2_SUPER_MAGIC) &&
338	    (sb->s_feature_incompat & EXT3_FEATURE_INCOMPAT_JOURNAL_DEV)) {
339		blocksize = EXT2_BLOCK_SIZE(sb);
340		blocknr = (blocksize == 1024) ? 2 : 1;
341		uuid_unparse(sb->s_uuid, jsb_buffer);
342		fprintf(out_file, "Ext2 superblock header found.\n");
343		if (dump_all) {
344			fprintf(out_file, "\tuuid=%s\n", jsb_buffer);
345			fprintf(out_file, "\tblocksize=%d\n", blocksize);
346			fprintf(out_file, "\tjournal data size %ld\n",
347				(long) sb->s_blocks_count);
348		}
349	}
350
351	/* Next, read the journal superblock */
352
353	retval = read_journal_block(cmdname, source, blocknr*blocksize,
354				    jsb_buffer, 1024, &got);
355	if (retval)
356		return;
357
358	jsb = (journal_superblock_t *) jsb_buffer;
359	if (be32_to_cpu(jsb->s_header.h_magic) != JFS_MAGIC_NUMBER) {
360		fprintf(out_file,
361			"Journal superblock magic number invalid!\n");
362		return;
363	}
364	blocksize = be32_to_cpu(jsb->s_blocksize);
365	transaction = be32_to_cpu(jsb->s_sequence);
366	blocknr = be32_to_cpu(jsb->s_start);
367
368	fprintf(out_file, "Journal starts at block %u, transaction %u\n",
369		blocknr, transaction);
370
371	if (!blocknr)
372		/* Empty journal, nothing to do. */
373		return;
374
375	while (1) {
376		retval = read_journal_block(cmdname, source,
377					    blocknr*blocksize, buf,
378					    blocksize, &got);
379		if (retval || got != blocksize)
380			return;
381
382		header = (journal_header_t *) buf;
383
384		magic = be32_to_cpu(header->h_magic);
385		sequence = be32_to_cpu(header->h_sequence);
386		blocktype = be32_to_cpu(header->h_blocktype);
387
388		if (magic != JFS_MAGIC_NUMBER) {
389			fprintf (out_file, "No magic number at block %u: "
390				 "end of journal.\n", blocknr);
391			return;
392		}
393
394		if (sequence != transaction) {
395			fprintf (out_file, "Found sequence %u (not %u) at "
396				 "block %u: end of journal.\n",
397				 sequence, transaction, blocknr);
398			return;
399		}
400
401		if (dump_descriptors) {
402			fprintf (out_file, "Found expected sequence %u, "
403				 "type %u (%s) at block %u\n",
404				 sequence, blocktype,
405				 type_to_name(blocktype), blocknr);
406		}
407
408		switch (blocktype) {
409		case JFS_DESCRIPTOR_BLOCK:
410			dump_descriptor_block(out_file, source, buf, jsb,
411					      &blocknr, blocksize,
412					      transaction);
413			continue;
414
415		case JFS_COMMIT_BLOCK:
416			transaction++;
417			blocknr++;
418			WRAP(jsb, blocknr);
419			continue;
420
421		case JFS_REVOKE_BLOCK:
422			dump_revoke_block(out_file, buf, jsb,
423					  blocknr, blocksize,
424					  transaction);
425			blocknr++;
426			WRAP(jsb, blocknr);
427			continue;
428
429		default:
430			fprintf (out_file, "Unexpected block type %u at "
431				 "block %u.\n", blocktype, blocknr);
432			return;
433		}
434	}
435}
436
437
438static void dump_descriptor_block(FILE *out_file,
439				  struct journal_source *source,
440				  char *buf,
441				  journal_superblock_t *jsb,
442				  unsigned int *blockp, int blocksize,
443				  tid_t transaction)
444{
445	int			offset;
446	char			*tagp;
447	journal_block_tag_t	*tag;
448	unsigned int		blocknr;
449	__u32			tag_block;
450	__u32			tag_flags;
451
452
453	offset = sizeof(journal_header_t);
454	blocknr = *blockp;
455
456	if (dump_all)
457		fprintf(out_file, "Dumping descriptor block, sequence %u, at "
458			"block %u:\n", transaction, blocknr);
459
460	++blocknr;
461	WRAP(jsb, blocknr);
462
463	do {
464		/* Work out the location of the current tag, and skip to
465		 * the next one... */
466		tagp = &buf[offset];
467		tag = (journal_block_tag_t *) tagp;
468		offset += sizeof(journal_block_tag_t);
469
470		/* ... and if we have gone too far, then we've reached the
471		   end of this block. */
472		if (offset > blocksize)
473			break;
474
475		tag_block = be32_to_cpu(tag->t_blocknr);
476		tag_flags = be32_to_cpu(tag->t_flags);
477
478		if (!(tag_flags & JFS_FLAG_SAME_UUID))
479			offset += 16;
480
481		dump_metadata_block(out_file, source, jsb,
482				    blocknr, tag_block, blocksize,
483				    transaction);
484
485		++blocknr;
486		WRAP(jsb, blocknr);
487
488	} while (!(tag_flags & JFS_FLAG_LAST_TAG));
489
490	*blockp = blocknr;
491}
492
493
494static void dump_revoke_block(FILE *out_file, char *buf,
495				  journal_superblock_t *jsb,
496				  unsigned int blocknr, int blocksize,
497				  tid_t transaction)
498{
499	int			offset, max;
500	journal_revoke_header_t *header;
501	unsigned int		*entry, rblock;
502
503	if (dump_all)
504		fprintf(out_file, "Dumping revoke block, sequence %u, at "
505			"block %u:\n", transaction, blocknr);
506
507	header = (journal_revoke_header_t *) buf;
508	offset = sizeof(journal_revoke_header_t);
509	max = be32_to_cpu(header->r_count);
510
511	while (offset < max) {
512		entry = (unsigned int *) (buf + offset);
513		rblock = be32_to_cpu(*entry);
514		if (dump_all || rblock == block_to_dump) {
515			fprintf(out_file, "  Revoke FS block %u", rblock);
516			if (dump_all)
517				fprintf(out_file, "\n");
518			else
519				fprintf(out_file," at block %u, sequence %u\n",
520					blocknr, transaction);
521		}
522		offset += 4;
523	}
524}
525
526
527static void show_extent(FILE *out_file, int start_extent, int end_extent,
528			__u32 first_block)
529{
530	if (start_extent >= 0 && first_block != 0)
531		fprintf(out_file, "(%d+%u): %u ",
532			start_extent, end_extent-start_extent, first_block);
533}
534
535static void show_indirect(FILE *out_file, const char *name, __u32 where)
536{
537	if (where)
538		fprintf(out_file, "(%s): %u ", name, where);
539}
540
541
542static void dump_metadata_block(FILE *out_file, struct journal_source *source,
543				journal_superblock_t *jsb,
544				unsigned int log_blocknr,
545				unsigned int fs_blocknr,
546				int blocksize,
547				tid_t transaction)
548{
549	unsigned int 	got;
550	int		retval;
551	char 		buf[8192];
552
553	if (!(dump_all
554	      || (fs_blocknr == block_to_dump)
555	      || (fs_blocknr == inode_block_to_dump)
556	      || (fs_blocknr == bitmap_to_dump)))
557		return;
558
559	fprintf(out_file, "  FS block %u logged at ", fs_blocknr);
560	if (!dump_all)
561		fprintf(out_file, "sequence %u, ", transaction);
562	fprintf(out_file, "journal block %u\n", log_blocknr);
563
564	/* There are two major special cases to parse:
565	 *
566	 * If this block is a block
567	 * bitmap block, we need to give it special treatment so that we
568	 * can log any allocates and deallocates which affect the
569	 * block_to_dump query block.
570	 *
571	 * If the block is an inode block for the inode being searched
572	 * for, then we need to dump the contents of that inode
573	 * structure symbolically.
574	 */
575
576	if (!(dump_contents && dump_all)
577	    && fs_blocknr != block_to_dump
578	    && fs_blocknr != bitmap_to_dump
579	    && fs_blocknr != inode_block_to_dump)
580		return;
581
582	retval = read_journal_block("logdump", source,
583				    blocksize * log_blocknr,
584				    buf, blocksize, &got);
585	if (retval)
586		return;
587
588	if (fs_blocknr == bitmap_to_dump) {
589		struct ext2_super_block *super;
590		int offset;
591
592		super = current_fs->super;
593		offset = ((fs_blocknr - super->s_first_data_block) %
594			  super->s_blocks_per_group);
595
596		fprintf(out_file, "    (block bitmap for block %u: "
597			"block is %s)\n",
598			block_to_dump,
599			ext2fs_test_bit(offset, buf) ? "SET" : "CLEAR");
600	}
601
602	if (fs_blocknr == inode_block_to_dump) {
603		struct ext2_inode *inode;
604		int first, prev, this, start_extent, i;
605
606		fprintf(out_file, "    (inode block for inode %u):\n",
607			inode_to_dump);
608
609		inode = (struct ext2_inode *) (buf + inode_offset_to_dump);
610		internal_dump_inode(out_file, "    ", inode_to_dump, inode, 0);
611
612		/* Dump out the direct/indirect blocks here:
613		 * internal_dump_inode can only dump them from the main
614		 * on-disk inode, not from the journaled copy of the
615		 * inode. */
616
617		fprintf (out_file, "    Blocks:  ");
618		first = prev = start_extent = -1;
619
620		for (i=0; i<EXT2_NDIR_BLOCKS; i++) {
621			this = inode->i_block[i];
622			if (start_extent >= 0  && this == prev+1) {
623				prev = this;
624				continue;
625			} else {
626				show_extent(out_file, start_extent, i, first);
627				start_extent = i;
628				first = prev = this;
629			}
630		}
631		show_extent(out_file, start_extent, i, first);
632		show_indirect(out_file, "IND", inode->i_block[i++]);
633		show_indirect(out_file, "DIND", inode->i_block[i++]);
634		show_indirect(out_file, "TIND", inode->i_block[i++]);
635
636		fprintf(out_file, "\n");
637	}
638
639	if (dump_contents)
640		do_hexdump(out_file, buf, blocksize);
641
642}
643
644static void do_hexdump (FILE *out_file, char *buf, int blocksize)
645{
646	int i,j;
647	int *intp;
648	char *charp;
649	unsigned char c;
650
651	intp = (int *) buf;
652	charp = (char *) buf;
653
654	for (i=0; i<blocksize; i+=16) {
655		fprintf(out_file, "    %04x:  ", i);
656		for (j=0; j<16; j+=4)
657			fprintf(out_file, "%08x ", *intp++);
658		for (j=0; j<16; j++) {
659			c = *charp++;
660			if (c < ' ' || c >= 127)
661				c = '.';
662			fprintf(out_file, "%c", c);
663		}
664		fprintf(out_file, "\n");
665	}
666}
667
668