Linux Audio

Check our new training course

Embedded Linux Audio

Check our new training course
with Creative Commons CC-BY-SA
lecture materials

Bootlin logo

Elixir Cross Referencer

Loading...
  1
  2
  3
  4
  5
  6
  7
  8
  9
 10
 11
 12
 13
 14
 15
 16
 17
 18
 19
 20
 21
 22
 23
 24
 25
 26
 27
 28
 29
 30
 31
 32
 33
 34
 35
 36
 37
 38
 39
 40
 41
 42
 43
 44
 45
 46
 47
 48
 49
 50
 51
 52
 53
 54
 55
 56
 57
 58
 59
 60
 61
 62
 63
 64
 65
 66
 67
 68
 69
 70
 71
 72
 73
 74
 75
 76
 77
 78
 79
 80
 81
 82
 83
 84
 85
 86
 87
 88
 89
 90
 91
 92
 93
 94
 95
 96
 97
 98
 99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
/*
 * mkjournal.c --- make a journal for a filesystem
 *
 * Copyright (C) 2000 Theodore Ts'o.
 *
 * %Begin-Header%
 * This file may be redistributed under the terms of the GNU Public
 * License.
 * %End-Header%
 */

#include <stdio.h>
#include <string.h>
#if HAVE_UNISTD_H
#include <unistd.h>
#endif
#if HAVE_ERRNO_H
#include <errno.h>
#endif
#include <fcntl.h>
#include <time.h>
#if HAVE_SYS_STAT_H
#include <sys/stat.h>
#endif
#if HAVE_SYS_TYPES_H
#include <sys/types.h>
#endif
#if HAVE_SYS_IOCTL_H
#include <sys/ioctl.h>
#endif
#if HAVE_NETINET_IN_H
#include <netinet/in.h>
#endif

#include "ext2_fs.h"
#include "../e2p/e2p.h"
#include "ext2fs.h"
#include "jfs_user.h"

/*
 * This function automatically sets up the journal superblock and
 * returns it as an allocated block.
 */
errcode_t ext2fs_create_journal_superblock(ext2_filsys fs,
					   __u32 size, int flags,
					   char  **ret_jsb)
{
	errcode_t		retval;
	journal_superblock_t	*jsb;

	if (size < 1024)
		return EXT2_ET_JOURNAL_TOO_SMALL;

	if ((retval = ext2fs_get_mem(fs->blocksize, &jsb)))
		return retval;

	memset (jsb, 0, fs->blocksize);

	jsb->s_header.h_magic = htonl(JFS_MAGIC_NUMBER);
	if (flags & EXT2_MKJOURNAL_V1_SUPER)
		jsb->s_header.h_blocktype = htonl(JFS_SUPERBLOCK_V1);
	else
		jsb->s_header.h_blocktype = htonl(JFS_SUPERBLOCK_V2);
	jsb->s_blocksize = htonl(fs->blocksize);
	jsb->s_maxlen = htonl(size);
	jsb->s_nr_users = htonl(1);
	jsb->s_first = htonl(1);
	jsb->s_sequence = htonl(1);
	memcpy(jsb->s_uuid, fs->super->s_uuid, sizeof(fs->super->s_uuid));
	/*
	 * If we're creating an external journal device, we need to
	 * adjust these fields.
	 */
	if (fs->super->s_feature_incompat &
	    EXT3_FEATURE_INCOMPAT_JOURNAL_DEV) {
		jsb->s_nr_users = 0;
		if (fs->blocksize == 1024)
			jsb->s_first = htonl(3);
		else
			jsb->s_first = htonl(2);
	}

	*ret_jsb = (char *) jsb;
	return 0;
}

/*
 * This function writes a journal using POSIX routines.  It is used
 * for creating external journals and creating journals on live
 * filesystems.
 */
static errcode_t write_journal_file(ext2_filsys fs, char *filename,
				    blk_t size, int flags)
{
	errcode_t	retval;
	char		*buf = 0;
	int		fd, ret_size;
	blk_t		i;

	if ((retval = ext2fs_create_journal_superblock(fs, size, flags, &buf)))
		return retval;

	/* Open the device or journal file */
	if ((fd = open(filename, O_WRONLY)) < 0) {
		retval = errno;
		goto errout;
	}

	/* Write the superblock out */
	retval = EXT2_ET_SHORT_WRITE;
	ret_size = write(fd, buf, fs->blocksize);
	if (ret_size < 0) {
		retval = errno;
		goto errout;
	}
	if (ret_size != (int) fs->blocksize)
		goto errout;
	memset(buf, 0, fs->blocksize);

	for (i = 1; i < size; i++) {
		ret_size = write(fd, buf, fs->blocksize);
		if (ret_size < 0) {
			retval = errno;
			goto errout;
		}
		if (ret_size != (int) fs->blocksize)
			goto errout;
	}
	close(fd);

	retval = 0;
errout:
	ext2fs_free_mem(&buf);
	return retval;
}

/*
 * Helper function for creating the journal using direct I/O routines
 */
struct mkjournal_struct {
	int		num_blocks;
	int		newblocks;
	char		*buf;
	errcode_t	err;
};

static int mkjournal_proc(ext2_filsys	fs,
			   blk_t	*blocknr,
			   e2_blkcnt_t	blockcnt,
			   blk_t	ref_block EXT2FS_ATTR((unused)),
			   int		ref_offset EXT2FS_ATTR((unused)),
			   void		*priv_data)
{
	struct mkjournal_struct *es = (struct mkjournal_struct *) priv_data;
	blk_t	new_blk;
	static blk_t	last_blk = 0;
	errcode_t	retval;

	if (*blocknr) {
		last_blk = *blocknr;
		return 0;
	}
	retval = ext2fs_new_block(fs, last_blk, 0, &new_blk);
	if (retval) {
		es->err = retval;
		return BLOCK_ABORT;
	}
	if (blockcnt > 0)
		es->num_blocks--;

	es->newblocks++;
	retval = io_channel_write_blk(fs->io, new_blk, 1, es->buf);

	if (blockcnt == 0)
		memset(es->buf, 0, fs->blocksize);

	if (retval) {
		es->err = retval;
		return BLOCK_ABORT;
	}
	*blocknr = new_blk;
	last_blk = new_blk;
	ext2fs_block_alloc_stats(fs, new_blk, +1);

	if (es->num_blocks == 0)
		return (BLOCK_CHANGED | BLOCK_ABORT);
	else
		return BLOCK_CHANGED;

}

/*
 * This function creates a journal using direct I/O routines.
 */
static errcode_t write_journal_inode(ext2_filsys fs, ext2_ino_t journal_ino,
				     blk_t size, int flags)
{
	char			*buf;
	errcode_t		retval;
	struct ext2_inode	inode;
	struct mkjournal_struct	es;

	if ((retval = ext2fs_create_journal_superblock(fs, size, flags, &buf)))
		return retval;

	if ((retval = ext2fs_read_bitmaps(fs)))
		return retval;

	if ((retval = ext2fs_read_inode(fs, journal_ino, &inode)))
		return retval;

	if (inode.i_blocks > 0)
		return EEXIST;

	es.num_blocks = size;
	es.newblocks = 0;
	es.buf = buf;
	es.err = 0;

	retval = ext2fs_block_iterate2(fs, journal_ino, BLOCK_FLAG_APPEND,
				       0, mkjournal_proc, &es);
	if (es.err) {
		retval = es.err;
		goto errout;
	}

	if ((retval = ext2fs_read_inode(fs, journal_ino, &inode)))
		goto errout;

	inode.i_size += fs->blocksize * size;
	inode.i_blocks += (fs->blocksize / 512) * es.newblocks;
	inode.i_mtime = inode.i_ctime = time(0);
	inode.i_links_count = 1;
	inode.i_mode = LINUX_S_IFREG | 0600;

	if ((retval = ext2fs_write_inode(fs, journal_ino, &inode)))
		goto errout;
	retval = 0;

	memcpy(fs->super->s_jnl_blocks, inode.i_block, EXT2_N_BLOCKS*4);
	fs->super->s_jnl_blocks[16] = inode.i_size;
	fs->super->s_jnl_backup_type = EXT3_JNL_BACKUP_BLOCKS;
	ext2fs_mark_super_dirty(fs);

errout:
	ext2fs_free_mem(&buf);
	return retval;
}

/*
 * This function adds a journal device to a filesystem
 */
errcode_t ext2fs_add_journal_device(ext2_filsys fs, ext2_filsys journal_dev)
{
	struct stat	st;
	errcode_t	retval;
	char		buf[1024];
	journal_superblock_t	*jsb;
	int		start;
	__u32		i, nr_users;

	/* Make sure the device exists and is a block device */
	if (stat(journal_dev->device_name, &st) < 0)
		return errno;

	if (!S_ISBLK(st.st_mode))
		return EXT2_ET_JOURNAL_NOT_BLOCK; /* Must be a block device */

	/* Get the journal superblock */
	start = 1;
	if (journal_dev->blocksize == 1024)
		start++;
	if ((retval = io_channel_read_blk(journal_dev->io, start, -1024, buf)))
		return retval;

	jsb = (journal_superblock_t *) buf;
	if ((jsb->s_header.h_magic != (unsigned) ntohl(JFS_MAGIC_NUMBER)) ||
	    (jsb->s_header.h_blocktype != (unsigned) ntohl(JFS_SUPERBLOCK_V2)))
		return EXT2_ET_NO_JOURNAL_SB;

	if (ntohl(jsb->s_blocksize) != (unsigned long) fs->blocksize)
		return EXT2_ET_UNEXPECTED_BLOCK_SIZE;

	/* Check and see if this filesystem has already been added */
	nr_users = ntohl(jsb->s_nr_users);
	for (i=0; i < nr_users; i++) {
		if (memcmp(fs->super->s_uuid,
			   &jsb->s_users[i*16], 16) == 0)
			break;
	}
	if (i >= nr_users) {
		memcpy(&jsb->s_users[nr_users*16],
		       fs->super->s_uuid, 16);
		jsb->s_nr_users = htonl(nr_users+1);
	}

	/* Writeback the journal superblock */
	if ((retval = io_channel_write_blk(journal_dev->io, start, -1024, buf)))
		return retval;

	fs->super->s_journal_inum = 0;
	fs->super->s_journal_dev = st.st_rdev;
	memcpy(fs->super->s_journal_uuid, jsb->s_uuid,
	       sizeof(fs->super->s_journal_uuid));
	fs->super->s_feature_compat |= EXT3_FEATURE_COMPAT_HAS_JOURNAL;
	ext2fs_mark_super_dirty(fs);
	return 0;
}

/*
 * This function adds a journal inode to a filesystem, using either
 * POSIX routines if the filesystem is mounted, or using direct I/O
 * functions if it is not.
 */
errcode_t ext2fs_add_journal_inode(ext2_filsys fs, blk_t size, int flags)
{
	errcode_t		retval;
	ext2_ino_t		journal_ino;
	struct stat		st;
	char			jfile[1024];
	int			fd, mount_flags, f;

	if ((retval = ext2fs_check_mount_point(fs->device_name, &mount_flags,
					       jfile, sizeof(jfile)-10)))
		return retval;

	if (mount_flags & EXT2_MF_MOUNTED) {
		strcat(jfile, "/.journal");

		/*
		 * If .../.journal already exists, make sure any
		 * immutable or append-only flags are cleared.
		 */
#if defined(HAVE_CHFLAGS) && defined(UF_NODUMP)
		(void) chflags (jfile, 0);
#else
#if HAVE_EXT2_IOCTLS
		fd = open(jfile, O_RDONLY);
		if (fd >= 0) {
			f = 0;
			ioctl(fd, EXT2_IOC_SETFLAGS, &f);
			close(fd);
		}
#endif
#endif

		/* Create the journal file */
		if ((fd = open(jfile, O_CREAT|O_WRONLY, 0600)) < 0)
			return errno;

		if ((retval = write_journal_file(fs, jfile, size, flags)))
			goto errout;

		/* Get inode number of the journal file */
		if (fstat(fd, &st) < 0)
			goto errout;

#if defined(HAVE_CHFLAGS) && defined(UF_NODUMP)
		retval = fchflags (fd, UF_NODUMP|UF_IMMUTABLE);
#else
#if HAVE_EXT2_IOCTLS
		f = EXT2_NODUMP_FL | EXT2_IMMUTABLE_FL;
		retval = ioctl(fd, EXT2_IOC_SETFLAGS, &f);
#endif
#endif
		if (retval)
			goto errout;

		close(fd);
		journal_ino = st.st_ino;
	} else {
		journal_ino = EXT2_JOURNAL_INO;
		if ((retval = write_journal_inode(fs, journal_ino,
						  size, flags)))
			return retval;
	}

	fs->super->s_journal_inum = journal_ino;
	fs->super->s_journal_dev = 0;
	memset(fs->super->s_journal_uuid, 0,
	       sizeof(fs->super->s_journal_uuid));
	fs->super->s_feature_compat |= EXT3_FEATURE_COMPAT_HAS_JOURNAL;

	ext2fs_mark_super_dirty(fs);
	return 0;
errout:
	close(fd);
	return retval;
}

#ifdef DEBUG
main(int argc, char **argv)
{
	errcode_t	retval;
	char		*device_name;
	ext2_filsys	fs;

	if (argc < 2) {
		fprintf(stderr, "Usage: %s filesystem\n", argv[0]);
		exit(1);
	}
	device_name = argv[1];

	retval = ext2fs_open (device_name, EXT2_FLAG_RW, 0, 0,
			      unix_io_manager, &fs);
	if (retval) {
		com_err(argv[0], retval, "while opening %s", device_name);
		exit(1);
	}

	retval = ext2fs_add_journal_inode(fs, 1024);
	if (retval) {
		com_err(argv[0], retval, "while adding journal to %s",
			device_name);
		exit(1);
	}
	retval = ext2fs_flush(fs);
	if (retval) {
		printf("Warning, had trouble writing out superblocks.\n");
	}
	ext2fs_close(fs);
	exit(0);

}
#endif