xref: /kernel/linux/linux-6.6/fs/minix/inode.c (revision 62306a36)
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/vfs.h>
21#include <linux/writeback.h>
22
23static int minix_write_inode(struct inode *inode,
24		struct writeback_control *wbc);
25static int minix_statfs(struct dentry *dentry, struct kstatfs *buf);
26static int minix_remount (struct super_block * sb, int * flags, char * data);
27
28static void minix_evict_inode(struct inode *inode)
29{
30	truncate_inode_pages_final(&inode->i_data);
31	if (!inode->i_nlink) {
32		inode->i_size = 0;
33		minix_truncate(inode);
34	}
35	invalidate_inode_buffers(inode);
36	clear_inode(inode);
37	if (!inode->i_nlink)
38		minix_free_inode(inode);
39}
40
41static void minix_put_super(struct super_block *sb)
42{
43	int i;
44	struct minix_sb_info *sbi = minix_sb(sb);
45
46	if (!sb_rdonly(sb)) {
47		if (sbi->s_version != MINIX_V3)	 /* s_state is now out from V3 sb */
48			sbi->s_ms->s_state = sbi->s_mount_state;
49		mark_buffer_dirty(sbi->s_sbh);
50	}
51	for (i = 0; i < sbi->s_imap_blocks; i++)
52		brelse(sbi->s_imap[i]);
53	for (i = 0; i < sbi->s_zmap_blocks; i++)
54		brelse(sbi->s_zmap[i]);
55	brelse (sbi->s_sbh);
56	kfree(sbi->s_imap);
57	sb->s_fs_info = NULL;
58	kfree(sbi);
59}
60
61static struct kmem_cache * minix_inode_cachep;
62
63static struct inode *minix_alloc_inode(struct super_block *sb)
64{
65	struct minix_inode_info *ei;
66	ei = alloc_inode_sb(sb, minix_inode_cachep, GFP_KERNEL);
67	if (!ei)
68		return NULL;
69	return &ei->vfs_inode;
70}
71
72static void minix_free_in_core_inode(struct inode *inode)
73{
74	kmem_cache_free(minix_inode_cachep, minix_i(inode));
75}
76
77static void init_once(void *foo)
78{
79	struct minix_inode_info *ei = (struct minix_inode_info *) foo;
80
81	inode_init_once(&ei->vfs_inode);
82}
83
84static int __init init_inodecache(void)
85{
86	minix_inode_cachep = kmem_cache_create("minix_inode_cache",
87					     sizeof(struct minix_inode_info),
88					     0, (SLAB_RECLAIM_ACCOUNT|
89						SLAB_MEM_SPREAD|SLAB_ACCOUNT),
90					     init_once);
91	if (minix_inode_cachep == NULL)
92		return -ENOMEM;
93	return 0;
94}
95
96static void destroy_inodecache(void)
97{
98	/*
99	 * Make sure all delayed rcu free inodes are flushed before we
100	 * destroy cache.
101	 */
102	rcu_barrier();
103	kmem_cache_destroy(minix_inode_cachep);
104}
105
106static const struct super_operations minix_sops = {
107	.alloc_inode	= minix_alloc_inode,
108	.free_inode	= minix_free_in_core_inode,
109	.write_inode	= minix_write_inode,
110	.evict_inode	= minix_evict_inode,
111	.put_super	= minix_put_super,
112	.statfs		= minix_statfs,
113	.remount_fs	= minix_remount,
114};
115
116static int minix_remount (struct super_block * sb, int * flags, char * data)
117{
118	struct minix_sb_info * sbi = minix_sb(sb);
119	struct minix_super_block * ms;
120
121	sync_filesystem(sb);
122	ms = sbi->s_ms;
123	if ((bool)(*flags & SB_RDONLY) == sb_rdonly(sb))
124		return 0;
125	if (*flags & SB_RDONLY) {
126		if (ms->s_state & MINIX_VALID_FS ||
127		    !(sbi->s_mount_state & MINIX_VALID_FS))
128			return 0;
129		/* Mounting a rw partition read-only. */
130		if (sbi->s_version != MINIX_V3)
131			ms->s_state = sbi->s_mount_state;
132		mark_buffer_dirty(sbi->s_sbh);
133	} else {
134	  	/* Mount a partition which is read-only, read-write. */
135		if (sbi->s_version != MINIX_V3) {
136			sbi->s_mount_state = ms->s_state;
137			ms->s_state &= ~MINIX_VALID_FS;
138		} else {
139			sbi->s_mount_state = MINIX_VALID_FS;
140		}
141		mark_buffer_dirty(sbi->s_sbh);
142
143		if (!(sbi->s_mount_state & MINIX_VALID_FS))
144			printk("MINIX-fs warning: remounting unchecked fs, "
145				"running fsck is recommended\n");
146		else if ((sbi->s_mount_state & MINIX_ERROR_FS))
147			printk("MINIX-fs warning: remounting fs with errors, "
148				"running fsck is recommended\n");
149	}
150	return 0;
151}
152
153static bool minix_check_superblock(struct super_block *sb)
154{
155	struct minix_sb_info *sbi = minix_sb(sb);
156
157	if (sbi->s_imap_blocks == 0 || sbi->s_zmap_blocks == 0)
158		return false;
159
160	/*
161	 * s_max_size must not exceed the block mapping limitation.  This check
162	 * is only needed for V1 filesystems, since V2/V3 support an extra level
163	 * of indirect blocks which places the limit well above U32_MAX.
164	 */
165	if (sbi->s_version == MINIX_V1 &&
166	    sb->s_maxbytes > (7 + 512 + 512*512) * BLOCK_SIZE)
167		return false;
168
169	return true;
170}
171
172static int minix_fill_super(struct super_block *s, void *data, int silent)
173{
174	struct buffer_head *bh;
175	struct buffer_head **map;
176	struct minix_super_block *ms;
177	struct minix3_super_block *m3s = NULL;
178	unsigned long i, block;
179	struct inode *root_inode;
180	struct minix_sb_info *sbi;
181	int ret = -EINVAL;
182
183	sbi = kzalloc(sizeof(struct minix_sb_info), GFP_KERNEL);
184	if (!sbi)
185		return -ENOMEM;
186	s->s_fs_info = sbi;
187
188	BUILD_BUG_ON(32 != sizeof (struct minix_inode));
189	BUILD_BUG_ON(64 != sizeof(struct minix2_inode));
190
191	if (!sb_set_blocksize(s, BLOCK_SIZE))
192		goto out_bad_hblock;
193
194	if (!(bh = sb_bread(s, 1)))
195		goto out_bad_sb;
196
197	ms = (struct minix_super_block *) bh->b_data;
198	sbi->s_ms = ms;
199	sbi->s_sbh = bh;
200	sbi->s_mount_state = ms->s_state;
201	sbi->s_ninodes = ms->s_ninodes;
202	sbi->s_nzones = ms->s_nzones;
203	sbi->s_imap_blocks = ms->s_imap_blocks;
204	sbi->s_zmap_blocks = ms->s_zmap_blocks;
205	sbi->s_firstdatazone = ms->s_firstdatazone;
206	sbi->s_log_zone_size = ms->s_log_zone_size;
207	s->s_maxbytes = ms->s_max_size;
208	s->s_magic = ms->s_magic;
209	if (s->s_magic == MINIX_SUPER_MAGIC) {
210		sbi->s_version = MINIX_V1;
211		sbi->s_dirsize = 16;
212		sbi->s_namelen = 14;
213		s->s_max_links = MINIX_LINK_MAX;
214	} else if (s->s_magic == MINIX_SUPER_MAGIC2) {
215		sbi->s_version = MINIX_V1;
216		sbi->s_dirsize = 32;
217		sbi->s_namelen = 30;
218		s->s_max_links = MINIX_LINK_MAX;
219	} else if (s->s_magic == MINIX2_SUPER_MAGIC) {
220		sbi->s_version = MINIX_V2;
221		sbi->s_nzones = ms->s_zones;
222		sbi->s_dirsize = 16;
223		sbi->s_namelen = 14;
224		s->s_max_links = MINIX2_LINK_MAX;
225	} else if (s->s_magic == MINIX2_SUPER_MAGIC2) {
226		sbi->s_version = MINIX_V2;
227		sbi->s_nzones = ms->s_zones;
228		sbi->s_dirsize = 32;
229		sbi->s_namelen = 30;
230		s->s_max_links = MINIX2_LINK_MAX;
231	} else if ( *(__u16 *)(bh->b_data + 24) == MINIX3_SUPER_MAGIC) {
232		m3s = (struct minix3_super_block *) bh->b_data;
233		s->s_magic = m3s->s_magic;
234		sbi->s_imap_blocks = m3s->s_imap_blocks;
235		sbi->s_zmap_blocks = m3s->s_zmap_blocks;
236		sbi->s_firstdatazone = m3s->s_firstdatazone;
237		sbi->s_log_zone_size = m3s->s_log_zone_size;
238		s->s_maxbytes = m3s->s_max_size;
239		sbi->s_ninodes = m3s->s_ninodes;
240		sbi->s_nzones = m3s->s_zones;
241		sbi->s_dirsize = 64;
242		sbi->s_namelen = 60;
243		sbi->s_version = MINIX_V3;
244		sbi->s_mount_state = MINIX_VALID_FS;
245		sb_set_blocksize(s, m3s->s_blocksize);
246		s->s_max_links = MINIX2_LINK_MAX;
247	} else
248		goto out_no_fs;
249
250	if (!minix_check_superblock(s))
251		goto out_illegal_sb;
252
253	/*
254	 * Allocate the buffer map to keep the superblock small.
255	 */
256	i = (sbi->s_imap_blocks + sbi->s_zmap_blocks) * sizeof(bh);
257	map = kzalloc(i, GFP_KERNEL);
258	if (!map)
259		goto out_no_map;
260	sbi->s_imap = &map[0];
261	sbi->s_zmap = &map[sbi->s_imap_blocks];
262
263	block=2;
264	for (i=0 ; i < sbi->s_imap_blocks ; i++) {
265		if (!(sbi->s_imap[i]=sb_bread(s, block)))
266			goto out_no_bitmap;
267		block++;
268	}
269	for (i=0 ; i < sbi->s_zmap_blocks ; i++) {
270		if (!(sbi->s_zmap[i]=sb_bread(s, block)))
271			goto out_no_bitmap;
272		block++;
273	}
274
275	minix_set_bit(0,sbi->s_imap[0]->b_data);
276	minix_set_bit(0,sbi->s_zmap[0]->b_data);
277
278	/* Apparently minix can create filesystems that allocate more blocks for
279	 * the bitmaps than needed.  We simply ignore that, but verify it didn't
280	 * create one with not enough blocks and bail out if so.
281	 */
282	block = minix_blocks_needed(sbi->s_ninodes, s->s_blocksize);
283	if (sbi->s_imap_blocks < block) {
284		printk("MINIX-fs: file system does not have enough "
285				"imap blocks allocated.  Refusing to mount.\n");
286		goto out_no_bitmap;
287	}
288
289	block = minix_blocks_needed(
290			(sbi->s_nzones - sbi->s_firstdatazone + 1),
291			s->s_blocksize);
292	if (sbi->s_zmap_blocks < block) {
293		printk("MINIX-fs: file system does not have enough "
294				"zmap blocks allocated.  Refusing to mount.\n");
295		goto out_no_bitmap;
296	}
297
298	/* set up enough so that it can read an inode */
299	s->s_op = &minix_sops;
300	s->s_time_min = 0;
301	s->s_time_max = U32_MAX;
302	root_inode = minix_iget(s, MINIX_ROOT_INO);
303	if (IS_ERR(root_inode)) {
304		ret = PTR_ERR(root_inode);
305		goto out_no_root;
306	}
307
308	ret = -ENOMEM;
309	s->s_root = d_make_root(root_inode);
310	if (!s->s_root)
311		goto out_no_root;
312
313	if (!sb_rdonly(s)) {
314		if (sbi->s_version != MINIX_V3) /* s_state is now out from V3 sb */
315			ms->s_state &= ~MINIX_VALID_FS;
316		mark_buffer_dirty(bh);
317	}
318	if (!(sbi->s_mount_state & MINIX_VALID_FS))
319		printk("MINIX-fs: mounting unchecked file system, "
320			"running fsck is recommended\n");
321	else if (sbi->s_mount_state & MINIX_ERROR_FS)
322		printk("MINIX-fs: mounting file system with errors, "
323			"running fsck is recommended\n");
324
325	return 0;
326
327out_no_root:
328	if (!silent)
329		printk("MINIX-fs: get root inode failed\n");
330	goto out_freemap;
331
332out_no_bitmap:
333	printk("MINIX-fs: bad superblock or unable to read bitmaps\n");
334out_freemap:
335	for (i = 0; i < sbi->s_imap_blocks; i++)
336		brelse(sbi->s_imap[i]);
337	for (i = 0; i < sbi->s_zmap_blocks; i++)
338		brelse(sbi->s_zmap[i]);
339	kfree(sbi->s_imap);
340	goto out_release;
341
342out_no_map:
343	ret = -ENOMEM;
344	if (!silent)
345		printk("MINIX-fs: can't allocate map\n");
346	goto out_release;
347
348out_illegal_sb:
349	if (!silent)
350		printk("MINIX-fs: bad superblock\n");
351	goto out_release;
352
353out_no_fs:
354	if (!silent)
355		printk("VFS: Can't find a Minix filesystem V1 | V2 | V3 "
356		       "on device %s.\n", s->s_id);
357out_release:
358	brelse(bh);
359	goto out;
360
361out_bad_hblock:
362	printk("MINIX-fs: blocksize too small for device\n");
363	goto out;
364
365out_bad_sb:
366	printk("MINIX-fs: unable to read superblock\n");
367out:
368	s->s_fs_info = NULL;
369	kfree(sbi);
370	return ret;
371}
372
373static int minix_statfs(struct dentry *dentry, struct kstatfs *buf)
374{
375	struct super_block *sb = dentry->d_sb;
376	struct minix_sb_info *sbi = minix_sb(sb);
377	u64 id = huge_encode_dev(sb->s_bdev->bd_dev);
378	buf->f_type = sb->s_magic;
379	buf->f_bsize = sb->s_blocksize;
380	buf->f_blocks = (sbi->s_nzones - sbi->s_firstdatazone) << sbi->s_log_zone_size;
381	buf->f_bfree = minix_count_free_blocks(sb);
382	buf->f_bavail = buf->f_bfree;
383	buf->f_files = sbi->s_ninodes;
384	buf->f_ffree = minix_count_free_inodes(sb);
385	buf->f_namelen = sbi->s_namelen;
386	buf->f_fsid = u64_to_fsid(id);
387
388	return 0;
389}
390
391static int minix_get_block(struct inode *inode, sector_t block,
392		    struct buffer_head *bh_result, int create)
393{
394	if (INODE_VERSION(inode) == MINIX_V1)
395		return V1_minix_get_block(inode, block, bh_result, create);
396	else
397		return V2_minix_get_block(inode, block, bh_result, create);
398}
399
400static int minix_writepage(struct page *page, struct writeback_control *wbc)
401{
402	return block_write_full_page(page, minix_get_block, wbc);
403}
404
405static int minix_read_folio(struct file *file, struct folio *folio)
406{
407	return block_read_full_folio(folio, minix_get_block);
408}
409
410int minix_prepare_chunk(struct page *page, loff_t pos, unsigned len)
411{
412	return __block_write_begin(page, pos, len, minix_get_block);
413}
414
415static void minix_write_failed(struct address_space *mapping, loff_t to)
416{
417	struct inode *inode = mapping->host;
418
419	if (to > inode->i_size) {
420		truncate_pagecache(inode, inode->i_size);
421		minix_truncate(inode);
422	}
423}
424
425static int minix_write_begin(struct file *file, struct address_space *mapping,
426			loff_t pos, unsigned len,
427			struct page **pagep, void **fsdata)
428{
429	int ret;
430
431	ret = block_write_begin(mapping, pos, len, pagep, minix_get_block);
432	if (unlikely(ret))
433		minix_write_failed(mapping, pos + len);
434
435	return ret;
436}
437
438static sector_t minix_bmap(struct address_space *mapping, sector_t block)
439{
440	return generic_block_bmap(mapping,block,minix_get_block);
441}
442
443static const struct address_space_operations minix_aops = {
444	.dirty_folio	= block_dirty_folio,
445	.invalidate_folio = block_invalidate_folio,
446	.read_folio = minix_read_folio,
447	.writepage = minix_writepage,
448	.write_begin = minix_write_begin,
449	.write_end = generic_write_end,
450	.bmap = minix_bmap,
451	.direct_IO = noop_direct_IO
452};
453
454static const struct inode_operations minix_symlink_inode_operations = {
455	.get_link	= page_get_link,
456	.getattr	= minix_getattr,
457};
458
459void minix_set_inode(struct inode *inode, dev_t rdev)
460{
461	if (S_ISREG(inode->i_mode)) {
462		inode->i_op = &minix_file_inode_operations;
463		inode->i_fop = &minix_file_operations;
464		inode->i_mapping->a_ops = &minix_aops;
465	} else if (S_ISDIR(inode->i_mode)) {
466		inode->i_op = &minix_dir_inode_operations;
467		inode->i_fop = &minix_dir_operations;
468		inode->i_mapping->a_ops = &minix_aops;
469	} else if (S_ISLNK(inode->i_mode)) {
470		inode->i_op = &minix_symlink_inode_operations;
471		inode_nohighmem(inode);
472		inode->i_mapping->a_ops = &minix_aops;
473	} else
474		init_special_inode(inode, inode->i_mode, rdev);
475}
476
477/*
478 * The minix V1 function to read an inode.
479 */
480static struct inode *V1_minix_iget(struct inode *inode)
481{
482	struct buffer_head * bh;
483	struct minix_inode * raw_inode;
484	struct minix_inode_info *minix_inode = minix_i(inode);
485	int i;
486
487	raw_inode = minix_V1_raw_inode(inode->i_sb, inode->i_ino, &bh);
488	if (!raw_inode) {
489		iget_failed(inode);
490		return ERR_PTR(-EIO);
491	}
492	if (raw_inode->i_nlinks == 0) {
493		printk("MINIX-fs: deleted inode referenced: %lu\n",
494		       inode->i_ino);
495		brelse(bh);
496		iget_failed(inode);
497		return ERR_PTR(-ESTALE);
498	}
499	inode->i_mode = raw_inode->i_mode;
500	i_uid_write(inode, raw_inode->i_uid);
501	i_gid_write(inode, raw_inode->i_gid);
502	set_nlink(inode, raw_inode->i_nlinks);
503	inode->i_size = raw_inode->i_size;
504	inode->i_mtime = inode->i_atime = inode_set_ctime(inode, raw_inode->i_time, 0);
505	inode->i_blocks = 0;
506	for (i = 0; i < 9; i++)
507		minix_inode->u.i1_data[i] = raw_inode->i_zone[i];
508	minix_set_inode(inode, old_decode_dev(raw_inode->i_zone[0]));
509	brelse(bh);
510	unlock_new_inode(inode);
511	return inode;
512}
513
514/*
515 * The minix V2 function to read an inode.
516 */
517static struct inode *V2_minix_iget(struct inode *inode)
518{
519	struct buffer_head * bh;
520	struct minix2_inode * raw_inode;
521	struct minix_inode_info *minix_inode = minix_i(inode);
522	int i;
523
524	raw_inode = minix_V2_raw_inode(inode->i_sb, inode->i_ino, &bh);
525	if (!raw_inode) {
526		iget_failed(inode);
527		return ERR_PTR(-EIO);
528	}
529	if (raw_inode->i_nlinks == 0) {
530		printk("MINIX-fs: deleted inode referenced: %lu\n",
531		       inode->i_ino);
532		brelse(bh);
533		iget_failed(inode);
534		return ERR_PTR(-ESTALE);
535	}
536	inode->i_mode = raw_inode->i_mode;
537	i_uid_write(inode, raw_inode->i_uid);
538	i_gid_write(inode, raw_inode->i_gid);
539	set_nlink(inode, raw_inode->i_nlinks);
540	inode->i_size = raw_inode->i_size;
541	inode->i_mtime.tv_sec = raw_inode->i_mtime;
542	inode->i_atime.tv_sec = raw_inode->i_atime;
543	inode_set_ctime(inode, raw_inode->i_ctime, 0);
544	inode->i_mtime.tv_nsec = 0;
545	inode->i_atime.tv_nsec = 0;
546	inode->i_blocks = 0;
547	for (i = 0; i < 10; i++)
548		minix_inode->u.i2_data[i] = raw_inode->i_zone[i];
549	minix_set_inode(inode, old_decode_dev(raw_inode->i_zone[0]));
550	brelse(bh);
551	unlock_new_inode(inode);
552	return inode;
553}
554
555/*
556 * The global function to read an inode.
557 */
558struct inode *minix_iget(struct super_block *sb, unsigned long ino)
559{
560	struct inode *inode;
561
562	inode = iget_locked(sb, ino);
563	if (!inode)
564		return ERR_PTR(-ENOMEM);
565	if (!(inode->i_state & I_NEW))
566		return inode;
567
568	if (INODE_VERSION(inode) == MINIX_V1)
569		return V1_minix_iget(inode);
570	else
571		return V2_minix_iget(inode);
572}
573
574/*
575 * The minix V1 function to synchronize an inode.
576 */
577static struct buffer_head * V1_minix_update_inode(struct inode * inode)
578{
579	struct buffer_head * bh;
580	struct minix_inode * raw_inode;
581	struct minix_inode_info *minix_inode = minix_i(inode);
582	int i;
583
584	raw_inode = minix_V1_raw_inode(inode->i_sb, inode->i_ino, &bh);
585	if (!raw_inode)
586		return NULL;
587	raw_inode->i_mode = inode->i_mode;
588	raw_inode->i_uid = fs_high2lowuid(i_uid_read(inode));
589	raw_inode->i_gid = fs_high2lowgid(i_gid_read(inode));
590	raw_inode->i_nlinks = inode->i_nlink;
591	raw_inode->i_size = inode->i_size;
592	raw_inode->i_time = inode->i_mtime.tv_sec;
593	if (S_ISCHR(inode->i_mode) || S_ISBLK(inode->i_mode))
594		raw_inode->i_zone[0] = old_encode_dev(inode->i_rdev);
595	else for (i = 0; i < 9; i++)
596		raw_inode->i_zone[i] = minix_inode->u.i1_data[i];
597	mark_buffer_dirty(bh);
598	return bh;
599}
600
601/*
602 * The minix V2 function to synchronize an inode.
603 */
604static struct buffer_head * V2_minix_update_inode(struct inode * inode)
605{
606	struct buffer_head * bh;
607	struct minix2_inode * raw_inode;
608	struct minix_inode_info *minix_inode = minix_i(inode);
609	int i;
610
611	raw_inode = minix_V2_raw_inode(inode->i_sb, inode->i_ino, &bh);
612	if (!raw_inode)
613		return NULL;
614	raw_inode->i_mode = inode->i_mode;
615	raw_inode->i_uid = fs_high2lowuid(i_uid_read(inode));
616	raw_inode->i_gid = fs_high2lowgid(i_gid_read(inode));
617	raw_inode->i_nlinks = inode->i_nlink;
618	raw_inode->i_size = inode->i_size;
619	raw_inode->i_mtime = inode->i_mtime.tv_sec;
620	raw_inode->i_atime = inode->i_atime.tv_sec;
621	raw_inode->i_ctime = inode_get_ctime(inode).tv_sec;
622	if (S_ISCHR(inode->i_mode) || S_ISBLK(inode->i_mode))
623		raw_inode->i_zone[0] = old_encode_dev(inode->i_rdev);
624	else for (i = 0; i < 10; i++)
625		raw_inode->i_zone[i] = minix_inode->u.i2_data[i];
626	mark_buffer_dirty(bh);
627	return bh;
628}
629
630static int minix_write_inode(struct inode *inode, struct writeback_control *wbc)
631{
632	int err = 0;
633	struct buffer_head *bh;
634
635	if (INODE_VERSION(inode) == MINIX_V1)
636		bh = V1_minix_update_inode(inode);
637	else
638		bh = V2_minix_update_inode(inode);
639	if (!bh)
640		return -EIO;
641	if (wbc->sync_mode == WB_SYNC_ALL && buffer_dirty(bh)) {
642		sync_dirty_buffer(bh);
643		if (buffer_req(bh) && !buffer_uptodate(bh)) {
644			printk("IO error syncing minix inode [%s:%08lx]\n",
645				inode->i_sb->s_id, inode->i_ino);
646			err = -EIO;
647		}
648	}
649	brelse (bh);
650	return err;
651}
652
653int minix_getattr(struct mnt_idmap *idmap, const struct path *path,
654		  struct kstat *stat, u32 request_mask, unsigned int flags)
655{
656	struct super_block *sb = path->dentry->d_sb;
657	struct inode *inode = d_inode(path->dentry);
658
659	generic_fillattr(&nop_mnt_idmap, request_mask, inode, stat);
660	if (INODE_VERSION(inode) == MINIX_V1)
661		stat->blocks = (BLOCK_SIZE / 512) * V1_minix_blocks(stat->size, sb);
662	else
663		stat->blocks = (sb->s_blocksize / 512) * V2_minix_blocks(stat->size, sb);
664	stat->blksize = sb->s_blocksize;
665	return 0;
666}
667
668/*
669 * The function that is called for file truncation.
670 */
671void minix_truncate(struct inode * inode)
672{
673	if (!(S_ISREG(inode->i_mode) || S_ISDIR(inode->i_mode) || S_ISLNK(inode->i_mode)))
674		return;
675	if (INODE_VERSION(inode) == MINIX_V1)
676		V1_minix_truncate(inode);
677	else
678		V2_minix_truncate(inode);
679}
680
681static struct dentry *minix_mount(struct file_system_type *fs_type,
682	int flags, const char *dev_name, void *data)
683{
684	return mount_bdev(fs_type, flags, dev_name, data, minix_fill_super);
685}
686
687static struct file_system_type minix_fs_type = {
688	.owner		= THIS_MODULE,
689	.name		= "minix",
690	.mount		= minix_mount,
691	.kill_sb	= kill_block_super,
692	.fs_flags	= FS_REQUIRES_DEV,
693};
694MODULE_ALIAS_FS("minix");
695
696static int __init init_minix_fs(void)
697{
698	int err = init_inodecache();
699	if (err)
700		goto out1;
701	err = register_filesystem(&minix_fs_type);
702	if (err)
703		goto out;
704	return 0;
705out:
706	destroy_inodecache();
707out1:
708	return err;
709}
710
711static void __exit exit_minix_fs(void)
712{
713        unregister_filesystem(&minix_fs_type);
714	destroy_inodecache();
715}
716
717module_init(init_minix_fs)
718module_exit(exit_minix_fs)
719MODULE_LICENSE("GPL");
720
721