1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 *  linux/fs/minix/inode.c
4 *
5 *  Copyright (C) 1991, 1992  Linus Torvalds
6 *
7 *  Copyright (C) 1996  Gertjan van Wingerde
8 *	Minix V2 fs support.
9 *
10 *  Modified for 680x0 by Andreas Schwab
11 *  Updated to filesystem version 3 by Daniel Aragones
12 */
13
14#include <linux/module.h>
15#include "minix.h"
16#include <linux/buffer_head.h>
17#include <linux/slab.h>
18#include <linux/init.h>
19#include <linux/highuid.h>
20#include <linux/mpage.h>
21#include <linux/vfs.h>
22#include <linux/writeback.h>
23
24static int minix_write_inode(struct inode *inode,
25		struct writeback_control *wbc);
26static int minix_statfs(struct dentry *dentry, struct kstatfs *buf);
27static int minix_remount (struct super_block * sb, int * flags, char * data);
28
29static void minix_evict_inode(struct inode *inode)
30{
31	truncate_inode_pages_final(&inode->i_data);
32	if (!inode->i_nlink) {
33		inode->i_size = 0;
34		minix_truncate(inode);
35	}
36	invalidate_inode_buffers(inode);
37	clear_inode(inode);
38	if (!inode->i_nlink)
39		minix_free_inode(inode);
40}
41
42static void minix_put_super(struct super_block *sb)
43{
44	int i;
45	struct minix_sb_info *sbi = minix_sb(sb);
46
47	if (!sb_rdonly(sb)) {
48		if (sbi->s_version != MINIX_V3)	 /* s_state is now out from V3 sb */
49			sbi->s_ms->s_state = sbi->s_mount_state;
50		mark_buffer_dirty(sbi->s_sbh);
51	}
52	for (i = 0; i < sbi->s_imap_blocks; i++)
53		brelse(sbi->s_imap[i]);
54	for (i = 0; i < sbi->s_zmap_blocks; i++)
55		brelse(sbi->s_zmap[i]);
56	brelse (sbi->s_sbh);
57	kfree(sbi->s_imap);
58	sb->s_fs_info = NULL;
59	kfree(sbi);
60}
61
62static struct kmem_cache * minix_inode_cachep;
63
64static struct inode *minix_alloc_inode(struct super_block *sb)
65{
66	struct minix_inode_info *ei;
67	ei = alloc_inode_sb(sb, minix_inode_cachep, GFP_KERNEL);
68	if (!ei)
69		return NULL;
70	return &ei->vfs_inode;
71}
72
73static void minix_free_in_core_inode(struct inode *inode)
74{
75	kmem_cache_free(minix_inode_cachep, minix_i(inode));
76}
77
78static void init_once(void *foo)
79{
80	struct minix_inode_info *ei = (struct minix_inode_info *) foo;
81
82	inode_init_once(&ei->vfs_inode);
83}
84
85static int __init init_inodecache(void)
86{
87	minix_inode_cachep = kmem_cache_create("minix_inode_cache",
88					     sizeof(struct minix_inode_info),
89					     0, (SLAB_RECLAIM_ACCOUNT|
90						SLAB_ACCOUNT),
91					     init_once);
92	if (minix_inode_cachep == NULL)
93		return -ENOMEM;
94	return 0;
95}
96
97static void destroy_inodecache(void)
98{
99	/*
100	 * Make sure all delayed rcu free inodes are flushed before we
101	 * destroy cache.
102	 */
103	rcu_barrier();
104	kmem_cache_destroy(minix_inode_cachep);
105}
106
107static const struct super_operations minix_sops = {
108	.alloc_inode	= minix_alloc_inode,
109	.free_inode	= minix_free_in_core_inode,
110	.write_inode	= minix_write_inode,
111	.evict_inode	= minix_evict_inode,
112	.put_super	= minix_put_super,
113	.statfs		= minix_statfs,
114	.remount_fs	= minix_remount,
115};
116
117static int minix_remount (struct super_block * sb, int * flags, char * data)
118{
119	struct minix_sb_info * sbi = minix_sb(sb);
120	struct minix_super_block * ms;
121
122	sync_filesystem(sb);
123	ms = sbi->s_ms;
124	if ((bool)(*flags & SB_RDONLY) == sb_rdonly(sb))
125		return 0;
126	if (*flags & SB_RDONLY) {
127		if (ms->s_state & MINIX_VALID_FS ||
128		    !(sbi->s_mount_state & MINIX_VALID_FS))
129			return 0;
130		/* Mounting a rw partition read-only. */
131		if (sbi->s_version != MINIX_V3)
132			ms->s_state = sbi->s_mount_state;
133		mark_buffer_dirty(sbi->s_sbh);
134	} else {
135	  	/* Mount a partition which is read-only, read-write. */
136		if (sbi->s_version != MINIX_V3) {
137			sbi->s_mount_state = ms->s_state;
138			ms->s_state &= ~MINIX_VALID_FS;
139		} else {
140			sbi->s_mount_state = MINIX_VALID_FS;
141		}
142		mark_buffer_dirty(sbi->s_sbh);
143
144		if (!(sbi->s_mount_state & MINIX_VALID_FS))
145			printk("MINIX-fs warning: remounting unchecked fs, "
146				"running fsck is recommended\n");
147		else if ((sbi->s_mount_state & MINIX_ERROR_FS))
148			printk("MINIX-fs warning: remounting fs with errors, "
149				"running fsck is recommended\n");
150	}
151	return 0;
152}
153
154static bool minix_check_superblock(struct super_block *sb)
155{
156	struct minix_sb_info *sbi = minix_sb(sb);
157
158	if (sbi->s_imap_blocks == 0 || sbi->s_zmap_blocks == 0)
159		return false;
160
161	/*
162	 * s_max_size must not exceed the block mapping limitation.  This check
163	 * is only needed for V1 filesystems, since V2/V3 support an extra level
164	 * of indirect blocks which places the limit well above U32_MAX.
165	 */
166	if (sbi->s_version == MINIX_V1 &&
167	    sb->s_maxbytes > (7 + 512 + 512*512) * BLOCK_SIZE)
168		return false;
169
170	return true;
171}
172
173static int minix_fill_super(struct super_block *s, void *data, int silent)
174{
175	struct buffer_head *bh;
176	struct buffer_head **map;
177	struct minix_super_block *ms;
178	struct minix3_super_block *m3s = NULL;
179	unsigned long i, block;
180	struct inode *root_inode;
181	struct minix_sb_info *sbi;
182	int ret = -EINVAL;
183
184	sbi = kzalloc(sizeof(struct minix_sb_info), GFP_KERNEL);
185	if (!sbi)
186		return -ENOMEM;
187	s->s_fs_info = sbi;
188
189	BUILD_BUG_ON(32 != sizeof (struct minix_inode));
190	BUILD_BUG_ON(64 != sizeof(struct minix2_inode));
191
192	if (!sb_set_blocksize(s, BLOCK_SIZE))
193		goto out_bad_hblock;
194
195	if (!(bh = sb_bread(s, 1)))
196		goto out_bad_sb;
197
198	ms = (struct minix_super_block *) bh->b_data;
199	sbi->s_ms = ms;
200	sbi->s_sbh = bh;
201	sbi->s_mount_state = ms->s_state;
202	sbi->s_ninodes = ms->s_ninodes;
203	sbi->s_nzones = ms->s_nzones;
204	sbi->s_imap_blocks = ms->s_imap_blocks;
205	sbi->s_zmap_blocks = ms->s_zmap_blocks;
206	sbi->s_firstdatazone = ms->s_firstdatazone;
207	sbi->s_log_zone_size = ms->s_log_zone_size;
208	s->s_maxbytes = ms->s_max_size;
209	s->s_magic = ms->s_magic;
210	if (s->s_magic == MINIX_SUPER_MAGIC) {
211		sbi->s_version = MINIX_V1;
212		sbi->s_dirsize = 16;
213		sbi->s_namelen = 14;
214		s->s_max_links = MINIX_LINK_MAX;
215	} else if (s->s_magic == MINIX_SUPER_MAGIC2) {
216		sbi->s_version = MINIX_V1;
217		sbi->s_dirsize = 32;
218		sbi->s_namelen = 30;
219		s->s_max_links = MINIX_LINK_MAX;
220	} else if (s->s_magic == MINIX2_SUPER_MAGIC) {
221		sbi->s_version = MINIX_V2;
222		sbi->s_nzones = ms->s_zones;
223		sbi->s_dirsize = 16;
224		sbi->s_namelen = 14;
225		s->s_max_links = MINIX2_LINK_MAX;
226	} else if (s->s_magic == MINIX2_SUPER_MAGIC2) {
227		sbi->s_version = MINIX_V2;
228		sbi->s_nzones = ms->s_zones;
229		sbi->s_dirsize = 32;
230		sbi->s_namelen = 30;
231		s->s_max_links = MINIX2_LINK_MAX;
232	} else if ( *(__u16 *)(bh->b_data + 24) == MINIX3_SUPER_MAGIC) {
233		m3s = (struct minix3_super_block *) bh->b_data;
234		s->s_magic = m3s->s_magic;
235		sbi->s_imap_blocks = m3s->s_imap_blocks;
236		sbi->s_zmap_blocks = m3s->s_zmap_blocks;
237		sbi->s_firstdatazone = m3s->s_firstdatazone;
238		sbi->s_log_zone_size = m3s->s_log_zone_size;
239		s->s_maxbytes = m3s->s_max_size;
240		sbi->s_ninodes = m3s->s_ninodes;
241		sbi->s_nzones = m3s->s_zones;
242		sbi->s_dirsize = 64;
243		sbi->s_namelen = 60;
244		sbi->s_version = MINIX_V3;
245		sbi->s_mount_state = MINIX_VALID_FS;
246		sb_set_blocksize(s, m3s->s_blocksize);
247		s->s_max_links = MINIX2_LINK_MAX;
248	} else
249		goto out_no_fs;
250
251	if (!minix_check_superblock(s))
252		goto out_illegal_sb;
253
254	/*
255	 * Allocate the buffer map to keep the superblock small.
256	 */
257	i = (sbi->s_imap_blocks + sbi->s_zmap_blocks) * sizeof(bh);
258	map = kzalloc(i, GFP_KERNEL);
259	if (!map)
260		goto out_no_map;
261	sbi->s_imap = &map[0];
262	sbi->s_zmap = &map[sbi->s_imap_blocks];
263
264	block=2;
265	for (i=0 ; i < sbi->s_imap_blocks ; i++) {
266		if (!(sbi->s_imap[i]=sb_bread(s, block)))
267			goto out_no_bitmap;
268		block++;
269	}
270	for (i=0 ; i < sbi->s_zmap_blocks ; i++) {
271		if (!(sbi->s_zmap[i]=sb_bread(s, block)))
272			goto out_no_bitmap;
273		block++;
274	}
275
276	minix_set_bit(0,sbi->s_imap[0]->b_data);
277	minix_set_bit(0,sbi->s_zmap[0]->b_data);
278
279	/* Apparently minix can create filesystems that allocate more blocks for
280	 * the bitmaps than needed.  We simply ignore that, but verify it didn't
281	 * create one with not enough blocks and bail out if so.
282	 */
283	block = minix_blocks_needed(sbi->s_ninodes, s->s_blocksize);
284	if (sbi->s_imap_blocks < block) {
285		printk("MINIX-fs: file system does not have enough "
286				"imap blocks allocated.  Refusing to mount.\n");
287		goto out_no_bitmap;
288	}
289
290	block = minix_blocks_needed(
291			(sbi->s_nzones - sbi->s_firstdatazone + 1),
292			s->s_blocksize);
293	if (sbi->s_zmap_blocks < block) {
294		printk("MINIX-fs: file system does not have enough "
295				"zmap blocks allocated.  Refusing to mount.\n");
296		goto out_no_bitmap;
297	}
298
299	/* set up enough so that it can read an inode */
300	s->s_op = &minix_sops;
301	s->s_time_min = 0;
302	s->s_time_max = U32_MAX;
303	root_inode = minix_iget(s, MINIX_ROOT_INO);
304	if (IS_ERR(root_inode)) {
305		ret = PTR_ERR(root_inode);
306		goto out_no_root;
307	}
308
309	ret = -ENOMEM;
310	s->s_root = d_make_root(root_inode);
311	if (!s->s_root)
312		goto out_no_root;
313
314	if (!sb_rdonly(s)) {
315		if (sbi->s_version != MINIX_V3) /* s_state is now out from V3 sb */
316			ms->s_state &= ~MINIX_VALID_FS;
317		mark_buffer_dirty(bh);
318	}
319	if (!(sbi->s_mount_state & MINIX_VALID_FS))
320		printk("MINIX-fs: mounting unchecked file system, "
321			"running fsck is recommended\n");
322	else if (sbi->s_mount_state & MINIX_ERROR_FS)
323		printk("MINIX-fs: mounting file system with errors, "
324			"running fsck is recommended\n");
325
326	return 0;
327
328out_no_root:
329	if (!silent)
330		printk("MINIX-fs: get root inode failed\n");
331	goto out_freemap;
332
333out_no_bitmap:
334	printk("MINIX-fs: bad superblock or unable to read bitmaps\n");
335out_freemap:
336	for (i = 0; i < sbi->s_imap_blocks; i++)
337		brelse(sbi->s_imap[i]);
338	for (i = 0; i < sbi->s_zmap_blocks; i++)
339		brelse(sbi->s_zmap[i]);
340	kfree(sbi->s_imap);
341	goto out_release;
342
343out_no_map:
344	ret = -ENOMEM;
345	if (!silent)
346		printk("MINIX-fs: can't allocate map\n");
347	goto out_release;
348
349out_illegal_sb:
350	if (!silent)
351		printk("MINIX-fs: bad superblock\n");
352	goto out_release;
353
354out_no_fs:
355	if (!silent)
356		printk("VFS: Can't find a Minix filesystem V1 | V2 | V3 "
357		       "on device %s.\n", s->s_id);
358out_release:
359	brelse(bh);
360	goto out;
361
362out_bad_hblock:
363	printk("MINIX-fs: blocksize too small for device\n");
364	goto out;
365
366out_bad_sb:
367	printk("MINIX-fs: unable to read superblock\n");
368out:
369	s->s_fs_info = NULL;
370	kfree(sbi);
371	return ret;
372}
373
374static int minix_statfs(struct dentry *dentry, struct kstatfs *buf)
375{
376	struct super_block *sb = dentry->d_sb;
377	struct minix_sb_info *sbi = minix_sb(sb);
378	u64 id = huge_encode_dev(sb->s_bdev->bd_dev);
379	buf->f_type = sb->s_magic;
380	buf->f_bsize = sb->s_blocksize;
381	buf->f_blocks = (sbi->s_nzones - sbi->s_firstdatazone) << sbi->s_log_zone_size;
382	buf->f_bfree = minix_count_free_blocks(sb);
383	buf->f_bavail = buf->f_bfree;
384	buf->f_files = sbi->s_ninodes;
385	buf->f_ffree = minix_count_free_inodes(sb);
386	buf->f_namelen = sbi->s_namelen;
387	buf->f_fsid = u64_to_fsid(id);
388
389	return 0;
390}
391
392static int minix_get_block(struct inode *inode, sector_t block,
393		    struct buffer_head *bh_result, int create)
394{
395	if (INODE_VERSION(inode) == MINIX_V1)
396		return V1_minix_get_block(inode, block, bh_result, create);
397	else
398		return V2_minix_get_block(inode, block, bh_result, create);
399}
400
401static int minix_writepages(struct address_space *mapping,
402		struct writeback_control *wbc)
403{
404	return mpage_writepages(mapping, wbc, minix_get_block);
405}
406
407static int minix_read_folio(struct file *file, struct folio *folio)
408{
409	return block_read_full_folio(folio, minix_get_block);
410}
411
412int minix_prepare_chunk(struct page *page, loff_t pos, unsigned len)
413{
414	return __block_write_begin(page, pos, len, minix_get_block);
415}
416
417static void minix_write_failed(struct address_space *mapping, loff_t to)
418{
419	struct inode *inode = mapping->host;
420
421	if (to > inode->i_size) {
422		truncate_pagecache(inode, inode->i_size);
423		minix_truncate(inode);
424	}
425}
426
427static int minix_write_begin(struct file *file, struct address_space *mapping,
428			loff_t pos, unsigned len,
429			struct page **pagep, void **fsdata)
430{
431	int ret;
432
433	ret = block_write_begin(mapping, pos, len, pagep, minix_get_block);
434	if (unlikely(ret))
435		minix_write_failed(mapping, pos + len);
436
437	return ret;
438}
439
440static sector_t minix_bmap(struct address_space *mapping, sector_t block)
441{
442	return generic_block_bmap(mapping,block,minix_get_block);
443}
444
445static const struct address_space_operations minix_aops = {
446	.dirty_folio	= block_dirty_folio,
447	.invalidate_folio = block_invalidate_folio,
448	.read_folio = minix_read_folio,
449	.writepages = minix_writepages,
450	.write_begin = minix_write_begin,
451	.write_end = generic_write_end,
452	.migrate_folio = buffer_migrate_folio,
453	.bmap = minix_bmap,
454	.direct_IO = noop_direct_IO
455};
456
457static const struct inode_operations minix_symlink_inode_operations = {
458	.get_link	= page_get_link,
459	.getattr	= minix_getattr,
460};
461
462void minix_set_inode(struct inode *inode, dev_t rdev)
463{
464	if (S_ISREG(inode->i_mode)) {
465		inode->i_op = &minix_file_inode_operations;
466		inode->i_fop = &minix_file_operations;
467		inode->i_mapping->a_ops = &minix_aops;
468	} else if (S_ISDIR(inode->i_mode)) {
469		inode->i_op = &minix_dir_inode_operations;
470		inode->i_fop = &minix_dir_operations;
471		inode->i_mapping->a_ops = &minix_aops;
472	} else if (S_ISLNK(inode->i_mode)) {
473		inode->i_op = &minix_symlink_inode_operations;
474		inode_nohighmem(inode);
475		inode->i_mapping->a_ops = &minix_aops;
476	} else
477		init_special_inode(inode, inode->i_mode, rdev);
478}
479
480/*
481 * The minix V1 function to read an inode.
482 */
483static struct inode *V1_minix_iget(struct inode *inode)
484{
485	struct buffer_head * bh;
486	struct minix_inode * raw_inode;
487	struct minix_inode_info *minix_inode = minix_i(inode);
488	int i;
489
490	raw_inode = minix_V1_raw_inode(inode->i_sb, inode->i_ino, &bh);
491	if (!raw_inode) {
492		iget_failed(inode);
493		return ERR_PTR(-EIO);
494	}
495	if (raw_inode->i_nlinks == 0) {
496		printk("MINIX-fs: deleted inode referenced: %lu\n",
497		       inode->i_ino);
498		brelse(bh);
499		iget_failed(inode);
500		return ERR_PTR(-ESTALE);
501	}
502	inode->i_mode = raw_inode->i_mode;
503	i_uid_write(inode, raw_inode->i_uid);
504	i_gid_write(inode, raw_inode->i_gid);
505	set_nlink(inode, raw_inode->i_nlinks);
506	inode->i_size = raw_inode->i_size;
507	inode_set_mtime_to_ts(inode,
508			      inode_set_atime_to_ts(inode, inode_set_ctime(inode, raw_inode->i_time, 0)));
509	inode->i_blocks = 0;
510	for (i = 0; i < 9; i++)
511		minix_inode->u.i1_data[i] = raw_inode->i_zone[i];
512	minix_set_inode(inode, old_decode_dev(raw_inode->i_zone[0]));
513	brelse(bh);
514	unlock_new_inode(inode);
515	return inode;
516}
517
518/*
519 * The minix V2 function to read an inode.
520 */
521static struct inode *V2_minix_iget(struct inode *inode)
522{
523	struct buffer_head * bh;
524	struct minix2_inode * raw_inode;
525	struct minix_inode_info *minix_inode = minix_i(inode);
526	int i;
527
528	raw_inode = minix_V2_raw_inode(inode->i_sb, inode->i_ino, &bh);
529	if (!raw_inode) {
530		iget_failed(inode);
531		return ERR_PTR(-EIO);
532	}
533	if (raw_inode->i_nlinks == 0) {
534		printk("MINIX-fs: deleted inode referenced: %lu\n",
535		       inode->i_ino);
536		brelse(bh);
537		iget_failed(inode);
538		return ERR_PTR(-ESTALE);
539	}
540	inode->i_mode = raw_inode->i_mode;
541	i_uid_write(inode, raw_inode->i_uid);
542	i_gid_write(inode, raw_inode->i_gid);
543	set_nlink(inode, raw_inode->i_nlinks);
544	inode->i_size = raw_inode->i_size;
545	inode_set_mtime(inode, raw_inode->i_mtime, 0);
546	inode_set_atime(inode, raw_inode->i_atime, 0);
547	inode_set_ctime(inode, raw_inode->i_ctime, 0);
548	inode->i_blocks = 0;
549	for (i = 0; i < 10; i++)
550		minix_inode->u.i2_data[i] = raw_inode->i_zone[i];
551	minix_set_inode(inode, old_decode_dev(raw_inode->i_zone[0]));
552	brelse(bh);
553	unlock_new_inode(inode);
554	return inode;
555}
556
557/*
558 * The global function to read an inode.
559 */
560struct inode *minix_iget(struct super_block *sb, unsigned long ino)
561{
562	struct inode *inode;
563
564	inode = iget_locked(sb, ino);
565	if (!inode)
566		return ERR_PTR(-ENOMEM);
567	if (!(inode->i_state & I_NEW))
568		return inode;
569
570	if (INODE_VERSION(inode) == MINIX_V1)
571		return V1_minix_iget(inode);
572	else
573		return V2_minix_iget(inode);
574}
575
576/*
577 * The minix V1 function to synchronize an inode.
578 */
579static struct buffer_head * V1_minix_update_inode(struct inode * inode)
580{
581	struct buffer_head * bh;
582	struct minix_inode * raw_inode;
583	struct minix_inode_info *minix_inode = minix_i(inode);
584	int i;
585
586	raw_inode = minix_V1_raw_inode(inode->i_sb, inode->i_ino, &bh);
587	if (!raw_inode)
588		return NULL;
589	raw_inode->i_mode = inode->i_mode;
590	raw_inode->i_uid = fs_high2lowuid(i_uid_read(inode));
591	raw_inode->i_gid = fs_high2lowgid(i_gid_read(inode));
592	raw_inode->i_nlinks = inode->i_nlink;
593	raw_inode->i_size = inode->i_size;
594	raw_inode->i_time = inode_get_mtime_sec(inode);
595	if (S_ISCHR(inode->i_mode) || S_ISBLK(inode->i_mode))
596		raw_inode->i_zone[0] = old_encode_dev(inode->i_rdev);
597	else for (i = 0; i < 9; i++)
598		raw_inode->i_zone[i] = minix_inode->u.i1_data[i];
599	mark_buffer_dirty(bh);
600	return bh;
601}
602
603/*
604 * The minix V2 function to synchronize an inode.
605 */
606static struct buffer_head * V2_minix_update_inode(struct inode * inode)
607{
608	struct buffer_head * bh;
609	struct minix2_inode * raw_inode;
610	struct minix_inode_info *minix_inode = minix_i(inode);
611	int i;
612
613	raw_inode = minix_V2_raw_inode(inode->i_sb, inode->i_ino, &bh);
614	if (!raw_inode)
615		return NULL;
616	raw_inode->i_mode = inode->i_mode;
617	raw_inode->i_uid = fs_high2lowuid(i_uid_read(inode));
618	raw_inode->i_gid = fs_high2lowgid(i_gid_read(inode));
619	raw_inode->i_nlinks = inode->i_nlink;
620	raw_inode->i_size = inode->i_size;
621	raw_inode->i_mtime = inode_get_mtime_sec(inode);
622	raw_inode->i_atime = inode_get_atime_sec(inode);
623	raw_inode->i_ctime = inode_get_ctime_sec(inode);
624	if (S_ISCHR(inode->i_mode) || S_ISBLK(inode->i_mode))
625		raw_inode->i_zone[0] = old_encode_dev(inode->i_rdev);
626	else for (i = 0; i < 10; i++)
627		raw_inode->i_zone[i] = minix_inode->u.i2_data[i];
628	mark_buffer_dirty(bh);
629	return bh;
630}
631
632static int minix_write_inode(struct inode *inode, struct writeback_control *wbc)
633{
634	int err = 0;
635	struct buffer_head *bh;
636
637	if (INODE_VERSION(inode) == MINIX_V1)
638		bh = V1_minix_update_inode(inode);
639	else
640		bh = V2_minix_update_inode(inode);
641	if (!bh)
642		return -EIO;
643	if (wbc->sync_mode == WB_SYNC_ALL && buffer_dirty(bh)) {
644		sync_dirty_buffer(bh);
645		if (buffer_req(bh) && !buffer_uptodate(bh)) {
646			printk("IO error syncing minix inode [%s:%08lx]\n",
647				inode->i_sb->s_id, inode->i_ino);
648			err = -EIO;
649		}
650	}
651	brelse (bh);
652	return err;
653}
654
655int minix_getattr(struct mnt_idmap *idmap, const struct path *path,
656		  struct kstat *stat, u32 request_mask, unsigned int flags)
657{
658	struct super_block *sb = path->dentry->d_sb;
659	struct inode *inode = d_inode(path->dentry);
660
661	generic_fillattr(&nop_mnt_idmap, request_mask, inode, stat);
662	if (INODE_VERSION(inode) == MINIX_V1)
663		stat->blocks = (BLOCK_SIZE / 512) * V1_minix_blocks(stat->size, sb);
664	else
665		stat->blocks = (sb->s_blocksize / 512) * V2_minix_blocks(stat->size, sb);
666	stat->blksize = sb->s_blocksize;
667	return 0;
668}
669
670/*
671 * The function that is called for file truncation.
672 */
673void minix_truncate(struct inode * inode)
674{
675	if (!(S_ISREG(inode->i_mode) || S_ISDIR(inode->i_mode) || S_ISLNK(inode->i_mode)))
676		return;
677	if (INODE_VERSION(inode) == MINIX_V1)
678		V1_minix_truncate(inode);
679	else
680		V2_minix_truncate(inode);
681}
682
683static struct dentry *minix_mount(struct file_system_type *fs_type,
684	int flags, const char *dev_name, void *data)
685{
686	return mount_bdev(fs_type, flags, dev_name, data, minix_fill_super);
687}
688
689static struct file_system_type minix_fs_type = {
690	.owner		= THIS_MODULE,
691	.name		= "minix",
692	.mount		= minix_mount,
693	.kill_sb	= kill_block_super,
694	.fs_flags	= FS_REQUIRES_DEV,
695};
696MODULE_ALIAS_FS("minix");
697
698static int __init init_minix_fs(void)
699{
700	int err = init_inodecache();
701	if (err)
702		goto out1;
703	err = register_filesystem(&minix_fs_type);
704	if (err)
705		goto out;
706	return 0;
707out:
708	destroy_inodecache();
709out1:
710	return err;
711}
712
713static void __exit exit_minix_fs(void)
714{
715        unregister_filesystem(&minix_fs_type);
716	destroy_inodecache();
717}
718
719module_init(init_minix_fs)
720module_exit(exit_minix_fs)
721MODULE_LICENSE("GPL");
722
723