summaryrefslogtreecommitdiffstats
path: root/fs/minix/inode.c
blob: 4d46a6a5907052de73638a347a9aa4238fa2bb37 (plain)
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
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
/*
 *  linux/fs/minix/inode.c
 *
 *  Copyright (C) 1991, 1992  Linus Torvalds
 *
 *  Copyright (C) 1996  Gertjan van Wingerde
 *	Minix V2 fs support.
 *
 *  Modified for 680x0 by Andreas Schwab
 *  Updated to filesystem version 3 by Daniel Aragones
 */

#include <linux/module.h>
#include "minix.h"
#include <linux/buffer_head.h>
#include <linux/slab.h>
#include <linux/init.h>
#include <linux/highuid.h>
#include <linux/vfs.h>
#include <linux/writeback.h>

static int minix_write_inode(struct inode *inode,
		struct writeback_control *wbc);
static int minix_statfs(struct dentry *dentry, struct kstatfs *buf);
static int minix_remount (struct super_block * sb, int * flags, char * data);

static void minix_evict_inode(struct inode *inode)
{
	truncate_inode_pages(&inode->i_data, 0);
	if (!inode->i_nlink) {
		inode->i_size = 0;
		minix_truncate(inode);
	}
	invalidate_inode_buffers(inode);
	end_writeback(inode);
	if (!inode->i_nlink)
		minix_free_inode(inode);
}

static void minix_put_super(struct super_block *sb)
{
	int i;
	struct minix_sb_info *sbi = minix_sb(sb);

	if (!(sb->s_flags & MS_RDONLY)) {
		if (sbi->s_version != MINIX_V3)	 /* s_state is now out from V3 sb */
			sbi->s_ms->s_state = sbi->s_mount_state;
		mark_buffer_dirty(sbi->s_sbh);
	}
	for (i = 0; i < sbi->s_imap_blocks; i++)
		brelse(sbi->s_imap[i]);
	for (i = 0; i < sbi->s_zmap_blocks; i++)
		brelse(sbi->s_zmap[i]);
	brelse (sbi->s_sbh);
	kfree(sbi->s_imap);
	sb->s_fs_info = NULL;
	kfree(sbi);
}

static struct kmem_cache * minix_inode_cachep;

static struct inode *minix_alloc_inode(struct super_block *sb)
{
	struct minix_inode_info *ei;
	ei = (struct minix_inode_info *)kmem_cache_alloc(minix_inode_cachep, GFP_KERNEL);
	if (!ei)
		return NULL;
	return &ei->vfs_inode;
}

static void minix_i_callback(struct rcu_head *head)
{
	struct inode *inode = container_of(head, struct inode, i_rcu);
	INIT_LIST_HEAD(&inode->i_dentry);
	kmem_cache_free(minix_inode_cachep, minix_i(inode));
}

static void minix_destroy_inode(struct inode *inode)
{
	call_rcu(&inode->i_rcu, minix_i_callback);
}

static void init_once(void *foo)
{
	struct minix_inode_info *ei = (struct minix_inode_info *) foo;

	inode_init_once(&ei->vfs_inode);
}

static int init_inodecache(void)
{
	minix_inode_cachep = kmem_cache_create("minix_inode_cache",
					     sizeof(struct minix_inode_info),
					     0, (SLAB_RECLAIM_ACCOUNT|
						SLAB_MEM_SPREAD),
					     init_once);
	if (minix_inode_cachep == NULL)
		return -ENOMEM;
	return 0;
}

static void destroy_inodecache(void)
{
	kmem_cache_destroy(minix_inode_cachep);
}

static const struct super_operations minix_sops = {
	.alloc_inode	= minix_alloc_inode,
	.destroy_inode	= minix_destroy_inode,
	.write_inode	= minix_write_inode,
	.evict_inode	= minix_evict_inode,
	.put_super	= minix_put_super,
	.statfs		= minix_statfs,
	.remount_fs	= minix_remount,
};

static int minix_remount (struct super_block * sb, int * flags, char * data)
{
	struct minix_sb_info * sbi = minix_sb(sb);
	struct minix_super_block * ms;

	ms = sbi->s_ms;
	if ((*flags & MS_RDONLY) == (sb->s_flags & MS_RDONLY))
		return 0;
	if (*flags & MS_RDONLY) {
		if (ms->s_state & MINIX_VALID_FS ||
		    !(sbi->s_mount_state & MINIX_VALID_FS))
			return 0;
		/* Mounting a rw partition read-only. */
		if (sbi->s_version != MINIX_V3)
			ms->s_state = sbi->s_mount_state;
		mark_buffer_dirty(sbi->s_sbh);
	} else {
	  	/* Mount a partition which is read-only, read-write. */
		if (sbi->s_version != MINIX_V3) {
			sbi->s_mount_state = ms->s_state;
			ms->s_state &= ~MINIX_VALID_FS;
		} else {
			sbi->s_mount_state = MINIX_VALID_FS;
		}
		mark_buffer_dirty(sbi->s_sbh);

		if (!(sbi->s_mount_state & MINIX_VALID_FS))
			printk("MINIX-fs warning: remounting unchecked fs, "
				"running fsck is recommended\n");
		else if ((sbi->s_mount_state & MINIX_ERROR_FS))
			printk("MINIX-fs warning: remounting fs with errors, "
				"running fsck is recommended\n");
	}
	return 0;
}

static int minix_fill_super(struct super_block *s, void *data, int silent)
{
	struct buffer_head *bh;
	struct buffer_head **map;
	struct minix_super_block *ms;
	struct minix3_super_block *m3s = NULL;
	unsigned long i, block;
	struct inode *root_inode;
	struct minix_sb_info *sbi;
	int ret = -EINVAL;

	sbi = kzalloc(sizeof(struct minix_sb_info), GFP_KERNEL);
	if (!sbi)
		return -ENOMEM;
	s->s_fs_info = sbi;

	BUILD_BUG_ON(32 != sizeof (struct minix_inode));
	BUILD_BUG_ON(64 != sizeof(struct minix2_inode));

	if (!sb_set_blocksize(s, BLOCK_SIZE))
		goto out_bad_hblock;

	if (!(bh = sb_bread(s, 1)))
		goto out_bad_sb;

	ms = (struct minix_super_block *) bh->b_data;
	sbi->s_ms = ms;
	sbi->s_sbh = bh;
	sbi->s_mount_state = ms->s_state;
	sbi->s_ninodes = ms->s_ninodes;
	sbi->s_nzones = ms->s_nzones;
	sbi->s_imap_blocks = ms->s_imap_blocks;
	sbi->s_zmap_blocks = ms->s_zmap_blocks;
	sbi->s_firstdatazone = ms->s_firstdatazone;
	sbi->s_log_zone_size = ms->s_log_zone_size;
	sbi->s_max_size = ms->s_max_size;
	s->s_magic = ms->s_magic;
	if (s->s_magic == MINIX_SUPER_MAGIC) {
		sbi->s_version = MINIX_V1;
		sbi->s_dirsize = 16;
		sbi->s_namelen = 14;
		sbi->s_link_max = MINIX_LINK_MAX;
	} else if (s->s_magic == MINIX_SUPER_MAGIC2) {
		sbi->s_version = MINIX_V1;
		sbi->s_dirsize = 32;
		sbi->s_namelen = 30;
		sbi->s_link_max = MINIX_LINK_MAX;
	} else if (s->s_magic == MINIX2_SUPER_MAGIC) {
		sbi->s_version = MINIX_V2;
		sbi->s_nzones = ms->s_zones;
		sbi->s_dirsize = 16;
		sbi->s_namelen = 14;
		sbi->s_link_max = MINIX2_LINK_MAX;
	} else if (s->s_magic == MINIX2_SUPER_MAGIC2) {
		sbi->s_version = MINIX_V2;
		sbi->s_nzones = ms->s_zones;
		sbi->s_dirsize = 32;
		sbi->s_namelen = 30;
		sbi->s_link_max = MINIX2_LINK_MAX;
	} else if ( *(__u16 *)(bh->b_data + 24) == MINIX3_SUPER_MAGIC) {
		m3s = (struct minix3_super_block *) bh->b_data;
		s->s_magic = m3s->s_magic;
		sbi->s_imap_blocks = m3s->s_imap_blocks;
		sbi->s_zmap_blocks = m3s->s_zmap_blocks;
		sbi->s_firstdatazone = m3s->s_firstdatazone;
		sbi->s_log_zone_size = m3s->s_log_zone_size;
		sbi->s_max_size = m3s->s_max_size;
		sbi->s_ninodes = m3s->s_ninodes;
		sbi->s_nzones = m3s->s_zones;
		sbi->s_dirsize = 64;
		sbi->s_namelen = 60;
		sbi->s_version = MINIX_V3;
		sbi->s_link_max = MINIX2_LINK_MAX;
		sbi->s_mount_state = MINIX_VALID_FS;
		sb_set_blocksize(s, m3s->s_blocksize);
	} else
		goto out_no_fs;

	/*
	 * Allocate the buffer map to keep the superblock small.
	 */
	if (sbi->s_imap_blocks == 0 || sbi->s_zmap_blocks == 0)
		goto out_illegal_sb;
	i = (sbi->s_imap_blocks + sbi->s_zmap_blocks) * sizeof(bh);
	map = kzalloc(i, GFP_KERNEL);
	if (!map)
		goto out_no_map;
	sbi->s_imap = &map[0];
	sbi->s_zmap = &map[sbi->s_imap_blocks];

	block=2;
	for (i=0 ; i < sbi->s_imap_blocks ; i++) {
		if (!(sbi->s_imap[i]=sb_bread(s, block)))
			goto out_no_bitmap;
		block++;
	}
	for (i=0 ; i < sbi->s_zmap_blocks ; i++) {
		if (!(sbi->s_zmap[i]=sb_bread(s, block)))
			goto out_no_bitmap;
		block++;
	}

	minix_set_bit(0,sbi->s_imap[0]->b_data);
	minix_set_bit(0,sbi->s_zmap[0]->b_data);

	/* set up enough so that it can read an inode */
	s->s_op = &minix_sops;
	root_inode = minix_iget(s, MINIX_ROOT_INO);
	if (IS_ERR(root_inode)) {
		ret = PTR_ERR(root_inode);
		goto out_no_root;
	}

	/* Apparently minix can create filesystems that allocate more blocks for
	 * the bitmaps than needed.  We simply ignore that, but verify it didn't
	 * create one with not enough blocks and bail out if so.
	 */
	block = minix_blocks_needed(sbi->s_ninodes, s->s_blocksize);
	if (sbi->s_imap_blocks < block) {
		printk("MINIX-fs: file system does not have enough "
				"imap blocks allocated.  Refusing to mount\n");
		goto out_iput;
	}

	block = minix_blocks_needed(
			(sbi->s_nzones - (sbi->s_firstdatazone + 1)),
			s->s_blocksize);
	if (sbi->s_zmap_blocks < block) {
		printk("MINIX-fs: file system does not have enough "
				"zmap blocks allocated.  Refusing to mount.\n");
		goto out_iput;
	}

	ret = -ENOMEM;
	s->s_root = d_alloc_root(root_inode);
	if (!s->s_root)
		goto out_iput;

	if (!(s->s_flags & MS_RDONLY)) {
		if (sbi->s_version != MINIX_V3) /* s_state is now out from V3 sb */
			ms->s_state &= ~MINIX_VALID_FS;
		mark_buffer_dirty(bh);
	}
	if (!(sbi->s_mount_state & MINIX_VALID_FS))
		printk("MINIX-fs: mounting unchecked file system, "
			"running fsck is recommended\n");
	else if (sbi->s_mount_state & MINIX_ERROR_FS)
		printk("MINIX-fs: mounting file system with errors, "
			"running fsck is recommended\n");

	return 0;

out_iput:
	iput(root_inode);
	goto out_freemap;

out_no_root:
	if (!silent)
		printk("MINIX-fs: get root inode failed\n");
	goto out_freemap;

out_no_bitmap:
	printk("MINIX-fs: bad superblock or unable to read bitmaps\n");
out_freemap:
	for (i = 0; i < sbi->s_imap_blocks; i++)
		brelse(sbi->s_imap[i]);
	for (i = 0; i < sbi->s_zmap_blocks; i++)
		brelse(sbi->s_zmap[i]);
	kfree(sbi->s_imap);
	goto out_release;

out_no_map:
	ret = -ENOMEM;
	if (!silent)
		printk("MINIX-fs: can't allocate map\n");
	goto out_release;

out_illegal_sb:
	if (!silent)
		printk("MINIX-fs: bad superblock\n");
	goto out_release;

out_no_fs:
	if (!silent)
		printk("VFS: Can't find a Minix filesystem V1 | V2 | V3 "
		       "on device %s.\n", s->s_id);
out_release:
	brelse(bh);
	goto out;

out_bad_hblock:
	printk("MINIX-fs: blocksize too small for device\n");
	goto out;

out_bad_sb:
	printk("MINIX-fs: unable to read superblock\n");
out:
	s->s_fs_info = NULL;
	kfree(sbi);
	return ret;
}

static int minix_statfs(struct dentry *dentry, struct kstatfs *buf)
{
	struct super_block *sb = dentry->d_sb;
	struct minix_sb_info *sbi = minix_sb(sb);
	u64 id = huge_encode_dev(sb->s_bdev->bd_dev);
	buf->f_type = sb->s_magic;
	buf->f_bsize = sb->s_blocksize;
	buf->f_blocks = (sbi->s_nzones - sbi->s_firstdatazone) << sbi->s_log_zone_size;
	buf->f_bfree = minix_count_free_blocks(sb);
	buf->f_bavail = buf->f_bfree;
	buf->f_files = sbi->s_ninodes;
	buf->f_ffree = minix_count_free_inodes(sb);
	buf->f_namelen = sbi->s_namelen;
	buf->f_fsid.val[0] = (u32)id;
	buf->f_fsid.val[1] = (u32)(id >> 32);

	return 0;
}

static int minix_get_block(struct inode *inode, sector_t block,
		    struct buffer_head *bh_result, int create)
{
	if (INODE_VERSION(inode) == MINIX_V1)
		return V1_minix_get_block(inode, block, bh_result, create);
	else
		return V2_minix_get_block(inode, block, bh_result, create);
}

static int minix_writepage(struct page *page, struct writeback_control *wbc)
{
	return block_write_full_page(page, minix_get_block, wbc);
}

static int minix_readpage(struct file *file, struct page *page)
{
	return block_read_full_page(page,minix_get_block);
}

int minix_prepare_chunk(struct page *page, loff_t pos, unsigned len)
{
	return __block_write_begin(page, pos, len, minix_get_block);
}

static int minix_write_begin(struct file *file, struct address_space *mapping,
			loff_t pos, unsigned len, unsigned flags,
			struct page **pagep, void **fsdata)
{
	int ret;

	ret = block_write_begin(mapping, pos, len, flags, pagep,
				minix_get_block);
	if (unlikely(ret)) {
		loff_t isize = mapping->host->i_size;
		if (pos + len > isize)
			vmtruncate(mapping->host, isize);
	}

	return ret;
}

static sector_t minix_bmap(struct address_space *mapping, sector_t block)
{
	return generic_block_bmap(mapping,block,minix_get_block);
}

static const struct address_space_operations minix_aops = {
	.readpage = minix_readpage,
	.writepage = minix_writepage,
	.write_begin = minix_write_begin,
	.write_end = generic_write_end,
	.bmap = minix_bmap
};

static const struct inode_operations minix_symlink_inode_operations = {
	.readlink	= generic_readlink,
	.follow_link	= page_follow_link_light,
	.put_link	= page_put_link,
	.getattr	= minix_getattr,
};

void minix_set_inode(struct inode *inode, dev_t rdev)
{
	if (S_ISREG(inode->i_mode)) {
		inode->i_op = &minix_file_inode_operations;
		inode->i_fop = &minix_file_operations;
		inode->i_mapping->a_ops = &minix_aops;
	} else if (S_ISDIR(inode->i_mode)) {
		inode->i_op = &minix_dir_inode_operations;
		inode->i_fop = &minix_dir_operations;
		inode->i_mapping->a_ops = &minix_aops;
	} else if (S_ISLNK(inode->i_mode)) {
		inode->i_op = &minix_symlink_inode_operations;
		inode->i_mapping->a_ops = &minix_aops;
	} else
		init_special_inode(inode, inode->i_mode, rdev);
}

/*
 * The minix V1 function to read an inode.
 */
static struct inode *V1_minix_iget(struct inode *inode)
{
	struct buffer_head * bh;
	struct minix_inode * raw_inode;
	struct minix_inode_info *minix_inode = minix_i(inode);
	int i;

	raw_inode = minix_V1_raw_inode(inode->i_sb, inode->i_ino, &bh);
	if (!raw_inode) {
		iget_failed(inode);
		return ERR_PTR(-EIO);
	}
	inode->i_mode = raw_inode->i_mode;
	inode->i_uid = (uid_t)raw_inode->i_uid;
	inode->i_gid = (gid_t)raw_inode->i_gid;
	set_nlink(inode, raw_inode->i_nlinks);
	inode->i_size = raw_inode->i_size;
	inode->i_mtime.tv_sec = inode->i_atime.tv_sec = inode->i_ctime.tv_sec = raw_inode->i_time;
	inode->i_mtime.tv_nsec = 0;
	inode->i_atime.tv_nsec = 0;
	inode->i_ctime.tv_nsec = 0;
	inode->i_blocks = 0;
	for (i = 0; i < 9; i++)
		minix_inode->u.i1_data[i] = raw_inode->i_zone[i];
	minix_set_inode(inode, old_decode_dev(raw_inode->i_zone[0]));
	brelse(bh);
	unlock_new_inode(inode);
	return inode;
}

/*
 * The minix V2 function to read an inode.
 */
static struct inode *V2_minix_iget(struct inode *inode)
{
	struct buffer_head * bh;
	struct minix2_inode * raw_inode;
	struct minix_inode_info *minix_inode = minix_i(inode);
	int i;

	raw_inode = minix_V2_raw_inode(inode->i_sb, inode->i_ino, &bh);
	if (!raw_inode) {
		iget_failed(inode);
		return ERR_PTR(-EIO);
	}
	inode->i_mode = raw_inode->i_mode;
	inode->i_uid = (uid_t)raw_inode->i_uid;
	inode->i_gid = (gid_t)raw_inode->i_gid;
	set_nlink(inode, raw_inode->i_nlinks);
	inode->i_size = raw_inode->i_size;
	inode->i_mtime.tv_sec = raw_inode->i_mtime;
	inode->i_atime.tv_sec = raw_inode->i_atime;
	inode->i_ctime.tv_sec = raw_inode->i_ctime;
	inode->i_mtime.tv_nsec = 0;
	inode->i_atime.tv_nsec = 0;
	inode->i_ctime.tv_nsec = 0;
	inode->i_blocks = 0;
	for (i = 0; i < 10; i++)
		minix_inode->u.i2_data[i] = raw_inode->i_zone[i];
	minix_set_inode(inode, old_decode_dev(raw_inode->i_zone[0]));
	brelse(bh);
	unlock_new_inode(inode);
	return inode;
}

/*
 * The global function to read an inode.
 */
struct inode *minix_iget(struct super_block *sb, unsigned long ino)
{
	struct inode *inode;

	inode = iget_locked(sb, ino);
	if (!inode)
		return ERR_PTR(-ENOMEM);
	if (!(inode->i_state & I_NEW))
		return inode;

	if (INODE_VERSION(inode) == MINIX_V1)
		return V1_minix_iget(inode);
	else
		return V2_minix_iget(inode);
}

/*
 * The minix V1 function to synchronize an inode.
 */
static struct buffer_head * V1_minix_update_inode(struct inode * inode)
{
	struct buffer_head * bh;
	struct minix_inode * raw_inode;
	struct minix_inode_info *minix_inode = minix_i(inode);
	int i;

	raw_inode = minix_V1_raw_inode(inode->i_sb, inode->i_ino, &bh);
	if (!raw_inode)
		return NULL;
	raw_inode->i_mode = inode->i_mode;
	raw_inode->i_uid = fs_high2lowuid(inode->i_uid);
	raw_inode->i_gid = fs_high2lowgid(inode->i_gid);
	raw_inode->i_nlinks = inode->i_nlink;
	raw_inode->i_size = inode->i_size;
	raw_inode->i_time = inode->i_mtime.tv_sec;
	if (S_ISCHR(inode->i_mode) || S_ISBLK(inode->i_mode))
		raw_inode->i_zone[0] = old_encode_dev(inode->i_rdev);
	else for (i = 0; i < 9; i++)
		raw_inode->i_zone[i] = minix_inode->u.i1_data[i];
	mark_buffer_dirty(bh);
	return bh;
}

/*
 * The minix V2 function to synchronize an inode.
 */
static struct buffer_head * V2_minix_update_inode(struct inode * inode)
{
	struct buffer_head * bh;
	struct minix2_inode * raw_inode;
	struct minix_inode_info *minix_inode = minix_i(inode);
	int i;

	raw_inode = minix_V2_raw_inode(inode->i_sb, inode->i_ino, &bh);
	if (!raw_inode)
		return NULL;
	raw_inode->i_mode = inode->i_mode;
	raw_inode->i_uid = fs_high2lowuid(inode->i_uid);
	raw_inode->i_gid = fs_high2lowgid(inode->i_gid);
	raw_inode->i_nlinks = inode->i_nlink;
	raw_inode->i_size = inode->i_size;
	raw_inode->i_mtime = inode->i_mtime.tv_sec;
	raw_inode->i_atime = inode->i_atime.tv_sec;
	raw_inode->i_ctime = inode->i_ctime.tv_sec;
	if (S_ISCHR(inode->i_mode) || S_ISBLK(inode->i_mode))
		raw_inode->i_zone[0] = old_encode_dev(inode->i_rdev);
	else for (i = 0; i < 10; i++)
		raw_inode->i_zone[i] = minix_inode->u.i2_data[i];
	mark_buffer_dirty(bh);
	return bh;
}

static int minix_write_inode(struct inode *inode, struct writeback_control *wbc)
{
	int err = 0;
	struct buffer_head *bh;

	if (INODE_VERSION(inode) == MINIX_V1)
		bh = V1_minix_update_inode(inode);
	else
		bh = V2_minix_update_inode(inode);
	if (!bh)
		return -EIO;
	if (wbc->sync_mode == WB_SYNC_ALL && buffer_dirty(bh)) {
		sync_dirty_buffer(bh);
		if (buffer_req(bh) && !buffer_uptodate(bh)) {
			printk("IO error syncing minix inode [%s:%08lx]\n",
				inode->i_sb->s_id, inode->i_ino);
			err = -EIO;
		}
	}
	brelse (bh);
	return err;
}

int minix_getattr(struct vfsmount *mnt, struct dentry *dentry, struct kstat *stat)
{
	struct super_block *sb = dentry->d_sb;
	generic_fillattr(dentry->d_inode, stat);
	if (INODE_VERSION(dentry->d_inode) == MINIX_V1)
		stat->blocks = (BLOCK_SIZE / 512) * V1_minix_blocks(stat->size, sb);
	else
		stat->blocks = (sb->s_blocksize / 512) * V2_minix_blocks(stat->size, sb);
	stat->blksize = sb->s_blocksize;
	return 0;
}

/*
 * The function that is called for file truncation.
 */
void minix_truncate(struct inode * inode)
{
	if (!(S_ISREG(inode->i_mode) || S_ISDIR(inode->i_mode) || S_ISLNK(inode->i_mode)))
		return;
	if (INODE_VERSION(inode) == MINIX_V1)
		V1_minix_truncate(inode);
	else
		V2_minix_truncate(inode);
}

static struct dentry *minix_mount(struct file_system_type *fs_type,
	int flags, const char *dev_name, void *data)
{
	return mount_bdev(fs_type, flags, dev_name, data, minix_fill_super);
}

static struct file_system_type minix_fs_type = {
	.owner		= THIS_MODULE,
	.name		= "minix",
	.mount		= minix_mount,
	.kill_sb	= kill_block_super,
	.fs_flags	= FS_REQUIRES_DEV,
};

static int __init init_minix_fs(void)
{
	int err = init_inodecache();
	if (err)
		goto out1;
	err = register_filesystem(&minix_fs_type);
	if (err)
		goto out;
	return 0;
out:
	destroy_inodecache();
out1:
	return err;
}

static void __exit exit_minix_fs(void)
{
        unregister_filesystem(&minix_fs_type);
	destroy_inodecache();
}

module_init(init_minix_fs)
module_exit(exit_minix_fs)
MODULE_LICENSE("GPL");