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v5.4
  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 = kmem_cache_alloc(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 int minix_fill_super(struct super_block *s, void *data, int silent)
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
154{
155	struct buffer_head *bh;
156	struct buffer_head **map;
157	struct minix_super_block *ms;
158	struct minix3_super_block *m3s = NULL;
159	unsigned long i, block;
160	struct inode *root_inode;
161	struct minix_sb_info *sbi;
162	int ret = -EINVAL;
 
163
164	sbi = kzalloc(sizeof(struct minix_sb_info), GFP_KERNEL);
165	if (!sbi)
166		return -ENOMEM;
167	s->s_fs_info = sbi;
168
169	BUILD_BUG_ON(32 != sizeof (struct minix_inode));
170	BUILD_BUG_ON(64 != sizeof(struct minix2_inode));
171
172	if (!sb_set_blocksize(s, BLOCK_SIZE))
173		goto out_bad_hblock;
174
175	if (!(bh = sb_bread(s, 1)))
176		goto out_bad_sb;
177
178	ms = (struct minix_super_block *) bh->b_data;
179	sbi->s_ms = ms;
180	sbi->s_sbh = bh;
181	sbi->s_mount_state = ms->s_state;
182	sbi->s_ninodes = ms->s_ninodes;
183	sbi->s_nzones = ms->s_nzones;
184	sbi->s_imap_blocks = ms->s_imap_blocks;
185	sbi->s_zmap_blocks = ms->s_zmap_blocks;
186	sbi->s_firstdatazone = ms->s_firstdatazone;
187	sbi->s_log_zone_size = ms->s_log_zone_size;
188	sbi->s_max_size = ms->s_max_size;
189	s->s_magic = ms->s_magic;
190	if (s->s_magic == MINIX_SUPER_MAGIC) {
191		sbi->s_version = MINIX_V1;
192		sbi->s_dirsize = 16;
193		sbi->s_namelen = 14;
194		s->s_max_links = MINIX_LINK_MAX;
195	} else if (s->s_magic == MINIX_SUPER_MAGIC2) {
196		sbi->s_version = MINIX_V1;
197		sbi->s_dirsize = 32;
198		sbi->s_namelen = 30;
199		s->s_max_links = MINIX_LINK_MAX;
200	} else if (s->s_magic == MINIX2_SUPER_MAGIC) {
201		sbi->s_version = MINIX_V2;
202		sbi->s_nzones = ms->s_zones;
203		sbi->s_dirsize = 16;
204		sbi->s_namelen = 14;
205		s->s_max_links = MINIX2_LINK_MAX;
206	} else if (s->s_magic == MINIX2_SUPER_MAGIC2) {
207		sbi->s_version = MINIX_V2;
208		sbi->s_nzones = ms->s_zones;
209		sbi->s_dirsize = 32;
210		sbi->s_namelen = 30;
211		s->s_max_links = MINIX2_LINK_MAX;
212	} else if ( *(__u16 *)(bh->b_data + 24) == MINIX3_SUPER_MAGIC) {
213		m3s = (struct minix3_super_block *) bh->b_data;
214		s->s_magic = m3s->s_magic;
215		sbi->s_imap_blocks = m3s->s_imap_blocks;
216		sbi->s_zmap_blocks = m3s->s_zmap_blocks;
217		sbi->s_firstdatazone = m3s->s_firstdatazone;
218		sbi->s_log_zone_size = m3s->s_log_zone_size;
219		sbi->s_max_size = m3s->s_max_size;
220		sbi->s_ninodes = m3s->s_ninodes;
221		sbi->s_nzones = m3s->s_zones;
222		sbi->s_dirsize = 64;
223		sbi->s_namelen = 60;
224		sbi->s_version = MINIX_V3;
225		sbi->s_mount_state = MINIX_VALID_FS;
226		sb_set_blocksize(s, m3s->s_blocksize);
227		s->s_max_links = MINIX2_LINK_MAX;
228	} else
229		goto out_no_fs;
230
 
 
 
231	/*
232	 * Allocate the buffer map to keep the superblock small.
233	 */
234	if (sbi->s_imap_blocks == 0 || sbi->s_zmap_blocks == 0)
235		goto out_illegal_sb;
236	i = (sbi->s_imap_blocks + sbi->s_zmap_blocks) * sizeof(bh);
237	map = kzalloc(i, GFP_KERNEL);
238	if (!map)
239		goto out_no_map;
240	sbi->s_imap = &map[0];
241	sbi->s_zmap = &map[sbi->s_imap_blocks];
242
243	block=2;
244	for (i=0 ; i < sbi->s_imap_blocks ; i++) {
245		if (!(sbi->s_imap[i]=sb_bread(s, block)))
246			goto out_no_bitmap;
247		block++;
248	}
249	for (i=0 ; i < sbi->s_zmap_blocks ; i++) {
250		if (!(sbi->s_zmap[i]=sb_bread(s, block)))
251			goto out_no_bitmap;
252		block++;
253	}
254
255	minix_set_bit(0,sbi->s_imap[0]->b_data);
256	minix_set_bit(0,sbi->s_zmap[0]->b_data);
257
258	/* Apparently minix can create filesystems that allocate more blocks for
259	 * the bitmaps than needed.  We simply ignore that, but verify it didn't
260	 * create one with not enough blocks and bail out if so.
261	 */
262	block = minix_blocks_needed(sbi->s_ninodes, s->s_blocksize);
263	if (sbi->s_imap_blocks < block) {
264		printk("MINIX-fs: file system does not have enough "
265				"imap blocks allocated.  Refusing to mount.\n");
266		goto out_no_bitmap;
267	}
268
269	block = minix_blocks_needed(
270			(sbi->s_nzones - sbi->s_firstdatazone + 1),
271			s->s_blocksize);
272	if (sbi->s_zmap_blocks < block) {
273		printk("MINIX-fs: file system does not have enough "
274				"zmap blocks allocated.  Refusing to mount.\n");
275		goto out_no_bitmap;
276	}
277
278	/* set up enough so that it can read an inode */
279	s->s_op = &minix_sops;
280	s->s_time_min = 0;
281	s->s_time_max = U32_MAX;
282	root_inode = minix_iget(s, MINIX_ROOT_INO);
283	if (IS_ERR(root_inode)) {
284		ret = PTR_ERR(root_inode);
285		goto out_no_root;
286	}
287
288	ret = -ENOMEM;
289	s->s_root = d_make_root(root_inode);
290	if (!s->s_root)
291		goto out_no_root;
292
293	if (!sb_rdonly(s)) {
294		if (sbi->s_version != MINIX_V3) /* s_state is now out from V3 sb */
295			ms->s_state &= ~MINIX_VALID_FS;
296		mark_buffer_dirty(bh);
297	}
298	if (!(sbi->s_mount_state & MINIX_VALID_FS))
299		printk("MINIX-fs: mounting unchecked file system, "
300			"running fsck is recommended\n");
301	else if (sbi->s_mount_state & MINIX_ERROR_FS)
302		printk("MINIX-fs: mounting file system with errors, "
303			"running fsck is recommended\n");
304
305	return 0;
306
307out_no_root:
308	if (!silent)
309		printk("MINIX-fs: get root inode failed\n");
310	goto out_freemap;
311
312out_no_bitmap:
313	printk("MINIX-fs: bad superblock or unable to read bitmaps\n");
314out_freemap:
315	for (i = 0; i < sbi->s_imap_blocks; i++)
316		brelse(sbi->s_imap[i]);
317	for (i = 0; i < sbi->s_zmap_blocks; i++)
318		brelse(sbi->s_zmap[i]);
319	kfree(sbi->s_imap);
320	goto out_release;
321
322out_no_map:
323	ret = -ENOMEM;
324	if (!silent)
325		printk("MINIX-fs: can't allocate map\n");
326	goto out_release;
327
328out_illegal_sb:
329	if (!silent)
330		printk("MINIX-fs: bad superblock\n");
331	goto out_release;
332
333out_no_fs:
334	if (!silent)
335		printk("VFS: Can't find a Minix filesystem V1 | V2 | V3 "
336		       "on device %s.\n", s->s_id);
337out_release:
338	brelse(bh);
339	goto out;
340
341out_bad_hblock:
342	printk("MINIX-fs: blocksize too small for device\n");
343	goto out;
344
345out_bad_sb:
346	printk("MINIX-fs: unable to read superblock\n");
347out:
348	s->s_fs_info = NULL;
349	kfree(sbi);
350	return ret;
351}
352
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
353static int minix_statfs(struct dentry *dentry, struct kstatfs *buf)
354{
355	struct super_block *sb = dentry->d_sb;
356	struct minix_sb_info *sbi = minix_sb(sb);
357	u64 id = huge_encode_dev(sb->s_bdev->bd_dev);
358	buf->f_type = sb->s_magic;
359	buf->f_bsize = sb->s_blocksize;
360	buf->f_blocks = (sbi->s_nzones - sbi->s_firstdatazone) << sbi->s_log_zone_size;
361	buf->f_bfree = minix_count_free_blocks(sb);
362	buf->f_bavail = buf->f_bfree;
363	buf->f_files = sbi->s_ninodes;
364	buf->f_ffree = minix_count_free_inodes(sb);
365	buf->f_namelen = sbi->s_namelen;
366	buf->f_fsid.val[0] = (u32)id;
367	buf->f_fsid.val[1] = (u32)(id >> 32);
368
369	return 0;
370}
371
372static int minix_get_block(struct inode *inode, sector_t block,
373		    struct buffer_head *bh_result, int create)
374{
375	if (INODE_VERSION(inode) == MINIX_V1)
376		return V1_minix_get_block(inode, block, bh_result, create);
377	else
378		return V2_minix_get_block(inode, block, bh_result, create);
379}
380
381static int minix_writepage(struct page *page, struct writeback_control *wbc)
 
382{
383	return block_write_full_page(page, minix_get_block, wbc);
384}
385
386static int minix_readpage(struct file *file, struct page *page)
387{
388	return block_read_full_page(page,minix_get_block);
389}
390
391int minix_prepare_chunk(struct page *page, loff_t pos, unsigned len)
392{
393	return __block_write_begin(page, pos, len, minix_get_block);
394}
395
396static void minix_write_failed(struct address_space *mapping, loff_t to)
397{
398	struct inode *inode = mapping->host;
399
400	if (to > inode->i_size) {
401		truncate_pagecache(inode, inode->i_size);
402		minix_truncate(inode);
403	}
404}
405
406static int minix_write_begin(struct file *file, struct address_space *mapping,
407			loff_t pos, unsigned len, unsigned flags,
408			struct page **pagep, void **fsdata)
409{
410	int ret;
411
412	ret = block_write_begin(mapping, pos, len, flags, pagep,
413				minix_get_block);
414	if (unlikely(ret))
415		minix_write_failed(mapping, pos + len);
416
417	return ret;
418}
419
420static sector_t minix_bmap(struct address_space *mapping, sector_t block)
421{
422	return generic_block_bmap(mapping,block,minix_get_block);
423}
424
425static const struct address_space_operations minix_aops = {
426	.readpage = minix_readpage,
427	.writepage = minix_writepage,
 
 
428	.write_begin = minix_write_begin,
429	.write_end = generic_write_end,
430	.bmap = minix_bmap
 
 
431};
432
433static const struct inode_operations minix_symlink_inode_operations = {
434	.get_link	= page_get_link,
435	.getattr	= minix_getattr,
436};
437
438void minix_set_inode(struct inode *inode, dev_t rdev)
439{
440	if (S_ISREG(inode->i_mode)) {
441		inode->i_op = &minix_file_inode_operations;
442		inode->i_fop = &minix_file_operations;
443		inode->i_mapping->a_ops = &minix_aops;
444	} else if (S_ISDIR(inode->i_mode)) {
445		inode->i_op = &minix_dir_inode_operations;
446		inode->i_fop = &minix_dir_operations;
447		inode->i_mapping->a_ops = &minix_aops;
448	} else if (S_ISLNK(inode->i_mode)) {
449		inode->i_op = &minix_symlink_inode_operations;
450		inode_nohighmem(inode);
451		inode->i_mapping->a_ops = &minix_aops;
452	} else
453		init_special_inode(inode, inode->i_mode, rdev);
454}
455
456/*
457 * The minix V1 function to read an inode.
458 */
459static struct inode *V1_minix_iget(struct inode *inode)
460{
461	struct buffer_head * bh;
462	struct minix_inode * raw_inode;
463	struct minix_inode_info *minix_inode = minix_i(inode);
464	int i;
465
466	raw_inode = minix_V1_raw_inode(inode->i_sb, inode->i_ino, &bh);
467	if (!raw_inode) {
468		iget_failed(inode);
469		return ERR_PTR(-EIO);
470	}
 
 
 
 
 
 
 
471	inode->i_mode = raw_inode->i_mode;
472	i_uid_write(inode, raw_inode->i_uid);
473	i_gid_write(inode, raw_inode->i_gid);
474	set_nlink(inode, raw_inode->i_nlinks);
475	inode->i_size = raw_inode->i_size;
476	inode->i_mtime.tv_sec = inode->i_atime.tv_sec = inode->i_ctime.tv_sec = raw_inode->i_time;
477	inode->i_mtime.tv_nsec = 0;
478	inode->i_atime.tv_nsec = 0;
479	inode->i_ctime.tv_nsec = 0;
480	inode->i_blocks = 0;
481	for (i = 0; i < 9; i++)
482		minix_inode->u.i1_data[i] = raw_inode->i_zone[i];
483	minix_set_inode(inode, old_decode_dev(raw_inode->i_zone[0]));
484	brelse(bh);
485	unlock_new_inode(inode);
486	return inode;
487}
488
489/*
490 * The minix V2 function to read an inode.
491 */
492static struct inode *V2_minix_iget(struct inode *inode)
493{
494	struct buffer_head * bh;
495	struct minix2_inode * raw_inode;
496	struct minix_inode_info *minix_inode = minix_i(inode);
497	int i;
498
499	raw_inode = minix_V2_raw_inode(inode->i_sb, inode->i_ino, &bh);
500	if (!raw_inode) {
501		iget_failed(inode);
502		return ERR_PTR(-EIO);
503	}
 
 
 
 
 
 
 
504	inode->i_mode = raw_inode->i_mode;
505	i_uid_write(inode, raw_inode->i_uid);
506	i_gid_write(inode, raw_inode->i_gid);
507	set_nlink(inode, raw_inode->i_nlinks);
508	inode->i_size = raw_inode->i_size;
509	inode->i_mtime.tv_sec = raw_inode->i_mtime;
510	inode->i_atime.tv_sec = raw_inode->i_atime;
511	inode->i_ctime.tv_sec = raw_inode->i_ctime;
512	inode->i_mtime.tv_nsec = 0;
513	inode->i_atime.tv_nsec = 0;
514	inode->i_ctime.tv_nsec = 0;
515	inode->i_blocks = 0;
516	for (i = 0; i < 10; i++)
517		minix_inode->u.i2_data[i] = raw_inode->i_zone[i];
518	minix_set_inode(inode, old_decode_dev(raw_inode->i_zone[0]));
519	brelse(bh);
520	unlock_new_inode(inode);
521	return inode;
522}
523
524/*
525 * The global function to read an inode.
526 */
527struct inode *minix_iget(struct super_block *sb, unsigned long ino)
528{
529	struct inode *inode;
530
531	inode = iget_locked(sb, ino);
532	if (!inode)
533		return ERR_PTR(-ENOMEM);
534	if (!(inode->i_state & I_NEW))
535		return inode;
536
537	if (INODE_VERSION(inode) == MINIX_V1)
538		return V1_minix_iget(inode);
539	else
540		return V2_minix_iget(inode);
541}
542
543/*
544 * The minix V1 function to synchronize an inode.
545 */
546static struct buffer_head * V1_minix_update_inode(struct inode * inode)
547{
548	struct buffer_head * bh;
549	struct minix_inode * raw_inode;
550	struct minix_inode_info *minix_inode = minix_i(inode);
551	int i;
552
553	raw_inode = minix_V1_raw_inode(inode->i_sb, inode->i_ino, &bh);
554	if (!raw_inode)
555		return NULL;
556	raw_inode->i_mode = inode->i_mode;
557	raw_inode->i_uid = fs_high2lowuid(i_uid_read(inode));
558	raw_inode->i_gid = fs_high2lowgid(i_gid_read(inode));
559	raw_inode->i_nlinks = inode->i_nlink;
560	raw_inode->i_size = inode->i_size;
561	raw_inode->i_time = inode->i_mtime.tv_sec;
562	if (S_ISCHR(inode->i_mode) || S_ISBLK(inode->i_mode))
563		raw_inode->i_zone[0] = old_encode_dev(inode->i_rdev);
564	else for (i = 0; i < 9; i++)
565		raw_inode->i_zone[i] = minix_inode->u.i1_data[i];
566	mark_buffer_dirty(bh);
567	return bh;
568}
569
570/*
571 * The minix V2 function to synchronize an inode.
572 */
573static struct buffer_head * V2_minix_update_inode(struct inode * inode)
574{
575	struct buffer_head * bh;
576	struct minix2_inode * raw_inode;
577	struct minix_inode_info *minix_inode = minix_i(inode);
578	int i;
579
580	raw_inode = minix_V2_raw_inode(inode->i_sb, inode->i_ino, &bh);
581	if (!raw_inode)
582		return NULL;
583	raw_inode->i_mode = inode->i_mode;
584	raw_inode->i_uid = fs_high2lowuid(i_uid_read(inode));
585	raw_inode->i_gid = fs_high2lowgid(i_gid_read(inode));
586	raw_inode->i_nlinks = inode->i_nlink;
587	raw_inode->i_size = inode->i_size;
588	raw_inode->i_mtime = inode->i_mtime.tv_sec;
589	raw_inode->i_atime = inode->i_atime.tv_sec;
590	raw_inode->i_ctime = inode->i_ctime.tv_sec;
591	if (S_ISCHR(inode->i_mode) || S_ISBLK(inode->i_mode))
592		raw_inode->i_zone[0] = old_encode_dev(inode->i_rdev);
593	else for (i = 0; i < 10; i++)
594		raw_inode->i_zone[i] = minix_inode->u.i2_data[i];
595	mark_buffer_dirty(bh);
596	return bh;
597}
598
599static int minix_write_inode(struct inode *inode, struct writeback_control *wbc)
600{
601	int err = 0;
602	struct buffer_head *bh;
603
604	if (INODE_VERSION(inode) == MINIX_V1)
605		bh = V1_minix_update_inode(inode);
606	else
607		bh = V2_minix_update_inode(inode);
608	if (!bh)
609		return -EIO;
610	if (wbc->sync_mode == WB_SYNC_ALL && buffer_dirty(bh)) {
611		sync_dirty_buffer(bh);
612		if (buffer_req(bh) && !buffer_uptodate(bh)) {
613			printk("IO error syncing minix inode [%s:%08lx]\n",
614				inode->i_sb->s_id, inode->i_ino);
615			err = -EIO;
616		}
617	}
618	brelse (bh);
619	return err;
620}
621
622int minix_getattr(const struct path *path, struct kstat *stat,
623		  u32 request_mask, unsigned int flags)
624{
625	struct super_block *sb = path->dentry->d_sb;
626	struct inode *inode = d_inode(path->dentry);
627
628	generic_fillattr(inode, stat);
629	if (INODE_VERSION(inode) == MINIX_V1)
630		stat->blocks = (BLOCK_SIZE / 512) * V1_minix_blocks(stat->size, sb);
631	else
632		stat->blocks = (sb->s_blocksize / 512) * V2_minix_blocks(stat->size, sb);
633	stat->blksize = sb->s_blocksize;
634	return 0;
635}
636
637/*
638 * The function that is called for file truncation.
639 */
640void minix_truncate(struct inode * inode)
641{
642	if (!(S_ISREG(inode->i_mode) || S_ISDIR(inode->i_mode) || S_ISLNK(inode->i_mode)))
643		return;
644	if (INODE_VERSION(inode) == MINIX_V1)
645		V1_minix_truncate(inode);
646	else
647		V2_minix_truncate(inode);
648}
649
650static struct dentry *minix_mount(struct file_system_type *fs_type,
651	int flags, const char *dev_name, void *data)
652{
653	return mount_bdev(fs_type, flags, dev_name, data, minix_fill_super);
654}
655
656static struct file_system_type minix_fs_type = {
657	.owner		= THIS_MODULE,
658	.name		= "minix",
659	.mount		= minix_mount,
660	.kill_sb	= kill_block_super,
661	.fs_flags	= FS_REQUIRES_DEV,
662};
663MODULE_ALIAS_FS("minix");
664
665static int __init init_minix_fs(void)
666{
667	int err = init_inodecache();
668	if (err)
669		goto out1;
670	err = register_filesystem(&minix_fs_type);
671	if (err)
672		goto out;
673	return 0;
674out:
675	destroy_inodecache();
676out1:
677	return err;
678}
679
680static void __exit exit_minix_fs(void)
681{
682        unregister_filesystem(&minix_fs_type);
683	destroy_inodecache();
684}
685
686module_init(init_minix_fs)
687module_exit(exit_minix_fs)
 
688MODULE_LICENSE("GPL");
689
v6.13.7
  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#include <linux/fs_context.h>
 24
 25static int minix_write_inode(struct inode *inode,
 26		struct writeback_control *wbc);
 27static int minix_statfs(struct dentry *dentry, struct kstatfs *buf);
 
 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};
115
116static int minix_reconfigure(struct fs_context *fc)
117{
 
118	struct minix_super_block * ms;
119	struct super_block *sb = fc->root->d_sb;
120	struct minix_sb_info * sbi = sb->s_fs_info;
121
122	sync_filesystem(sb);
123	ms = sbi->s_ms;
124	if ((bool)(fc->sb_flags & SB_RDONLY) == sb_rdonly(sb))
125		return 0;
126	if (fc->sb_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, struct fs_context *fc)
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	int silent = fc->sb_flags & SB_SILENT;
184
185	sbi = kzalloc(sizeof(struct minix_sb_info), GFP_KERNEL);
186	if (!sbi)
187		return -ENOMEM;
188	s->s_fs_info = sbi;
189
190	BUILD_BUG_ON(32 != sizeof (struct minix_inode));
191	BUILD_BUG_ON(64 != sizeof(struct minix2_inode));
192
193	if (!sb_set_blocksize(s, BLOCK_SIZE))
194		goto out_bad_hblock;
195
196	if (!(bh = sb_bread(s, 1)))
197		goto out_bad_sb;
198
199	ms = (struct minix_super_block *) bh->b_data;
200	sbi->s_ms = ms;
201	sbi->s_sbh = bh;
202	sbi->s_mount_state = ms->s_state;
203	sbi->s_ninodes = ms->s_ninodes;
204	sbi->s_nzones = ms->s_nzones;
205	sbi->s_imap_blocks = ms->s_imap_blocks;
206	sbi->s_zmap_blocks = ms->s_zmap_blocks;
207	sbi->s_firstdatazone = ms->s_firstdatazone;
208	sbi->s_log_zone_size = ms->s_log_zone_size;
209	s->s_maxbytes = ms->s_max_size;
210	s->s_magic = ms->s_magic;
211	if (s->s_magic == MINIX_SUPER_MAGIC) {
212		sbi->s_version = MINIX_V1;
213		sbi->s_dirsize = 16;
214		sbi->s_namelen = 14;
215		s->s_max_links = MINIX_LINK_MAX;
216	} else if (s->s_magic == MINIX_SUPER_MAGIC2) {
217		sbi->s_version = MINIX_V1;
218		sbi->s_dirsize = 32;
219		sbi->s_namelen = 30;
220		s->s_max_links = MINIX_LINK_MAX;
221	} else if (s->s_magic == MINIX2_SUPER_MAGIC) {
222		sbi->s_version = MINIX_V2;
223		sbi->s_nzones = ms->s_zones;
224		sbi->s_dirsize = 16;
225		sbi->s_namelen = 14;
226		s->s_max_links = MINIX2_LINK_MAX;
227	} else if (s->s_magic == MINIX2_SUPER_MAGIC2) {
228		sbi->s_version = MINIX_V2;
229		sbi->s_nzones = ms->s_zones;
230		sbi->s_dirsize = 32;
231		sbi->s_namelen = 30;
232		s->s_max_links = MINIX2_LINK_MAX;
233	} else if ( *(__u16 *)(bh->b_data + 24) == MINIX3_SUPER_MAGIC) {
234		m3s = (struct minix3_super_block *) bh->b_data;
235		s->s_magic = m3s->s_magic;
236		sbi->s_imap_blocks = m3s->s_imap_blocks;
237		sbi->s_zmap_blocks = m3s->s_zmap_blocks;
238		sbi->s_firstdatazone = m3s->s_firstdatazone;
239		sbi->s_log_zone_size = m3s->s_log_zone_size;
240		s->s_maxbytes = m3s->s_max_size;
241		sbi->s_ninodes = m3s->s_ninodes;
242		sbi->s_nzones = m3s->s_zones;
243		sbi->s_dirsize = 64;
244		sbi->s_namelen = 60;
245		sbi->s_version = MINIX_V3;
246		sbi->s_mount_state = MINIX_VALID_FS;
247		sb_set_blocksize(s, m3s->s_blocksize);
248		s->s_max_links = MINIX2_LINK_MAX;
249	} else
250		goto out_no_fs;
251
252	if (!minix_check_superblock(s))
253		goto out_illegal_sb;
254
255	/*
256	 * Allocate the buffer map to keep the superblock small.
257	 */
 
 
258	i = (sbi->s_imap_blocks + sbi->s_zmap_blocks) * sizeof(bh);
259	map = kzalloc(i, GFP_KERNEL);
260	if (!map)
261		goto out_no_map;
262	sbi->s_imap = &map[0];
263	sbi->s_zmap = &map[sbi->s_imap_blocks];
264
265	block=2;
266	for (i=0 ; i < sbi->s_imap_blocks ; i++) {
267		if (!(sbi->s_imap[i]=sb_bread(s, block)))
268			goto out_no_bitmap;
269		block++;
270	}
271	for (i=0 ; i < sbi->s_zmap_blocks ; i++) {
272		if (!(sbi->s_zmap[i]=sb_bread(s, block)))
273			goto out_no_bitmap;
274		block++;
275	}
276
277	minix_set_bit(0,sbi->s_imap[0]->b_data);
278	minix_set_bit(0,sbi->s_zmap[0]->b_data);
279
280	/* Apparently minix can create filesystems that allocate more blocks for
281	 * the bitmaps than needed.  We simply ignore that, but verify it didn't
282	 * create one with not enough blocks and bail out if so.
283	 */
284	block = minix_blocks_needed(sbi->s_ninodes, s->s_blocksize);
285	if (sbi->s_imap_blocks < block) {
286		printk("MINIX-fs: file system does not have enough "
287				"imap blocks allocated.  Refusing to mount.\n");
288		goto out_no_bitmap;
289	}
290
291	block = minix_blocks_needed(
292			(sbi->s_nzones - sbi->s_firstdatazone + 1),
293			s->s_blocksize);
294	if (sbi->s_zmap_blocks < block) {
295		printk("MINIX-fs: file system does not have enough "
296				"zmap blocks allocated.  Refusing to mount.\n");
297		goto out_no_bitmap;
298	}
299
300	/* set up enough so that it can read an inode */
301	s->s_op = &minix_sops;
302	s->s_time_min = 0;
303	s->s_time_max = U32_MAX;
304	root_inode = minix_iget(s, MINIX_ROOT_INO);
305	if (IS_ERR(root_inode)) {
306		ret = PTR_ERR(root_inode);
307		goto out_no_root;
308	}
309
310	ret = -ENOMEM;
311	s->s_root = d_make_root(root_inode);
312	if (!s->s_root)
313		goto out_no_root;
314
315	if (!sb_rdonly(s)) {
316		if (sbi->s_version != MINIX_V3) /* s_state is now out from V3 sb */
317			ms->s_state &= ~MINIX_VALID_FS;
318		mark_buffer_dirty(bh);
319	}
320	if (!(sbi->s_mount_state & MINIX_VALID_FS))
321		printk("MINIX-fs: mounting unchecked file system, "
322			"running fsck is recommended\n");
323	else if (sbi->s_mount_state & MINIX_ERROR_FS)
324		printk("MINIX-fs: mounting file system with errors, "
325			"running fsck is recommended\n");
326
327	return 0;
328
329out_no_root:
330	if (!silent)
331		printk("MINIX-fs: get root inode failed\n");
332	goto out_freemap;
333
334out_no_bitmap:
335	printk("MINIX-fs: bad superblock or unable to read bitmaps\n");
336out_freemap:
337	for (i = 0; i < sbi->s_imap_blocks; i++)
338		brelse(sbi->s_imap[i]);
339	for (i = 0; i < sbi->s_zmap_blocks; i++)
340		brelse(sbi->s_zmap[i]);
341	kfree(sbi->s_imap);
342	goto out_release;
343
344out_no_map:
345	ret = -ENOMEM;
346	if (!silent)
347		printk("MINIX-fs: can't allocate map\n");
348	goto out_release;
349
350out_illegal_sb:
351	if (!silent)
352		printk("MINIX-fs: bad superblock\n");
353	goto out_release;
354
355out_no_fs:
356	if (!silent)
357		printk("VFS: Can't find a Minix filesystem V1 | V2 | V3 "
358		       "on device %s.\n", s->s_id);
359out_release:
360	brelse(bh);
361	goto out;
362
363out_bad_hblock:
364	printk("MINIX-fs: blocksize too small for device\n");
365	goto out;
366
367out_bad_sb:
368	printk("MINIX-fs: unable to read superblock\n");
369out:
370	s->s_fs_info = NULL;
371	kfree(sbi);
372	return ret;
373}
374
375static int minix_get_tree(struct fs_context *fc)
376{
377	 return get_tree_bdev(fc, minix_fill_super);
378}
379
380static const struct fs_context_operations minix_context_ops = {
381	.get_tree	= minix_get_tree,
382	.reconfigure	= minix_reconfigure,
383};
384
385static int minix_init_fs_context(struct fs_context *fc)
386{
387	fc->ops = &minix_context_ops;
388
389	return 0;
390}
391
392static int minix_statfs(struct dentry *dentry, struct kstatfs *buf)
393{
394	struct super_block *sb = dentry->d_sb;
395	struct minix_sb_info *sbi = minix_sb(sb);
396	u64 id = huge_encode_dev(sb->s_bdev->bd_dev);
397	buf->f_type = sb->s_magic;
398	buf->f_bsize = sb->s_blocksize;
399	buf->f_blocks = (sbi->s_nzones - sbi->s_firstdatazone) << sbi->s_log_zone_size;
400	buf->f_bfree = minix_count_free_blocks(sb);
401	buf->f_bavail = buf->f_bfree;
402	buf->f_files = sbi->s_ninodes;
403	buf->f_ffree = minix_count_free_inodes(sb);
404	buf->f_namelen = sbi->s_namelen;
405	buf->f_fsid = u64_to_fsid(id);
 
406
407	return 0;
408}
409
410static int minix_get_block(struct inode *inode, sector_t block,
411		    struct buffer_head *bh_result, int create)
412{
413	if (INODE_VERSION(inode) == MINIX_V1)
414		return V1_minix_get_block(inode, block, bh_result, create);
415	else
416		return V2_minix_get_block(inode, block, bh_result, create);
417}
418
419static int minix_writepages(struct address_space *mapping,
420		struct writeback_control *wbc)
421{
422	return mpage_writepages(mapping, wbc, minix_get_block);
423}
424
425static int minix_read_folio(struct file *file, struct folio *folio)
426{
427	return block_read_full_folio(folio, minix_get_block);
428}
429
430int minix_prepare_chunk(struct folio *folio, loff_t pos, unsigned len)
431{
432	return __block_write_begin(folio, pos, len, minix_get_block);
433}
434
435static void minix_write_failed(struct address_space *mapping, loff_t to)
436{
437	struct inode *inode = mapping->host;
438
439	if (to > inode->i_size) {
440		truncate_pagecache(inode, inode->i_size);
441		minix_truncate(inode);
442	}
443}
444
445static int minix_write_begin(struct file *file, struct address_space *mapping,
446			loff_t pos, unsigned len,
447			struct folio **foliop, void **fsdata)
448{
449	int ret;
450
451	ret = block_write_begin(mapping, pos, len, foliop, minix_get_block);
 
452	if (unlikely(ret))
453		minix_write_failed(mapping, pos + len);
454
455	return ret;
456}
457
458static sector_t minix_bmap(struct address_space *mapping, sector_t block)
459{
460	return generic_block_bmap(mapping,block,minix_get_block);
461}
462
463static const struct address_space_operations minix_aops = {
464	.dirty_folio	= block_dirty_folio,
465	.invalidate_folio = block_invalidate_folio,
466	.read_folio = minix_read_folio,
467	.writepages = minix_writepages,
468	.write_begin = minix_write_begin,
469	.write_end = generic_write_end,
470	.migrate_folio = buffer_migrate_folio,
471	.bmap = minix_bmap,
472	.direct_IO = noop_direct_IO
473};
474
475static const struct inode_operations minix_symlink_inode_operations = {
476	.get_link	= page_get_link,
477	.getattr	= minix_getattr,
478};
479
480void minix_set_inode(struct inode *inode, dev_t rdev)
481{
482	if (S_ISREG(inode->i_mode)) {
483		inode->i_op = &minix_file_inode_operations;
484		inode->i_fop = &minix_file_operations;
485		inode->i_mapping->a_ops = &minix_aops;
486	} else if (S_ISDIR(inode->i_mode)) {
487		inode->i_op = &minix_dir_inode_operations;
488		inode->i_fop = &minix_dir_operations;
489		inode->i_mapping->a_ops = &minix_aops;
490	} else if (S_ISLNK(inode->i_mode)) {
491		inode->i_op = &minix_symlink_inode_operations;
492		inode_nohighmem(inode);
493		inode->i_mapping->a_ops = &minix_aops;
494	} else
495		init_special_inode(inode, inode->i_mode, rdev);
496}
497
498/*
499 * The minix V1 function to read an inode.
500 */
501static struct inode *V1_minix_iget(struct inode *inode)
502{
503	struct buffer_head * bh;
504	struct minix_inode * raw_inode;
505	struct minix_inode_info *minix_inode = minix_i(inode);
506	int i;
507
508	raw_inode = minix_V1_raw_inode(inode->i_sb, inode->i_ino, &bh);
509	if (!raw_inode) {
510		iget_failed(inode);
511		return ERR_PTR(-EIO);
512	}
513	if (raw_inode->i_nlinks == 0) {
514		printk("MINIX-fs: deleted inode referenced: %lu\n",
515		       inode->i_ino);
516		brelse(bh);
517		iget_failed(inode);
518		return ERR_PTR(-ESTALE);
519	}
520	inode->i_mode = raw_inode->i_mode;
521	i_uid_write(inode, raw_inode->i_uid);
522	i_gid_write(inode, raw_inode->i_gid);
523	set_nlink(inode, raw_inode->i_nlinks);
524	inode->i_size = raw_inode->i_size;
525	inode_set_mtime_to_ts(inode,
526			      inode_set_atime_to_ts(inode, inode_set_ctime(inode, raw_inode->i_time, 0)));
 
 
527	inode->i_blocks = 0;
528	for (i = 0; i < 9; i++)
529		minix_inode->u.i1_data[i] = raw_inode->i_zone[i];
530	minix_set_inode(inode, old_decode_dev(raw_inode->i_zone[0]));
531	brelse(bh);
532	unlock_new_inode(inode);
533	return inode;
534}
535
536/*
537 * The minix V2 function to read an inode.
538 */
539static struct inode *V2_minix_iget(struct inode *inode)
540{
541	struct buffer_head * bh;
542	struct minix2_inode * raw_inode;
543	struct minix_inode_info *minix_inode = minix_i(inode);
544	int i;
545
546	raw_inode = minix_V2_raw_inode(inode->i_sb, inode->i_ino, &bh);
547	if (!raw_inode) {
548		iget_failed(inode);
549		return ERR_PTR(-EIO);
550	}
551	if (raw_inode->i_nlinks == 0) {
552		printk("MINIX-fs: deleted inode referenced: %lu\n",
553		       inode->i_ino);
554		brelse(bh);
555		iget_failed(inode);
556		return ERR_PTR(-ESTALE);
557	}
558	inode->i_mode = raw_inode->i_mode;
559	i_uid_write(inode, raw_inode->i_uid);
560	i_gid_write(inode, raw_inode->i_gid);
561	set_nlink(inode, raw_inode->i_nlinks);
562	inode->i_size = raw_inode->i_size;
563	inode_set_mtime(inode, raw_inode->i_mtime, 0);
564	inode_set_atime(inode, raw_inode->i_atime, 0);
565	inode_set_ctime(inode, raw_inode->i_ctime, 0);
 
 
 
566	inode->i_blocks = 0;
567	for (i = 0; i < 10; i++)
568		minix_inode->u.i2_data[i] = raw_inode->i_zone[i];
569	minix_set_inode(inode, old_decode_dev(raw_inode->i_zone[0]));
570	brelse(bh);
571	unlock_new_inode(inode);
572	return inode;
573}
574
575/*
576 * The global function to read an inode.
577 */
578struct inode *minix_iget(struct super_block *sb, unsigned long ino)
579{
580	struct inode *inode;
581
582	inode = iget_locked(sb, ino);
583	if (!inode)
584		return ERR_PTR(-ENOMEM);
585	if (!(inode->i_state & I_NEW))
586		return inode;
587
588	if (INODE_VERSION(inode) == MINIX_V1)
589		return V1_minix_iget(inode);
590	else
591		return V2_minix_iget(inode);
592}
593
594/*
595 * The minix V1 function to synchronize an inode.
596 */
597static struct buffer_head * V1_minix_update_inode(struct inode * inode)
598{
599	struct buffer_head * bh;
600	struct minix_inode * raw_inode;
601	struct minix_inode_info *minix_inode = minix_i(inode);
602	int i;
603
604	raw_inode = minix_V1_raw_inode(inode->i_sb, inode->i_ino, &bh);
605	if (!raw_inode)
606		return NULL;
607	raw_inode->i_mode = inode->i_mode;
608	raw_inode->i_uid = fs_high2lowuid(i_uid_read(inode));
609	raw_inode->i_gid = fs_high2lowgid(i_gid_read(inode));
610	raw_inode->i_nlinks = inode->i_nlink;
611	raw_inode->i_size = inode->i_size;
612	raw_inode->i_time = inode_get_mtime_sec(inode);
613	if (S_ISCHR(inode->i_mode) || S_ISBLK(inode->i_mode))
614		raw_inode->i_zone[0] = old_encode_dev(inode->i_rdev);
615	else for (i = 0; i < 9; i++)
616		raw_inode->i_zone[i] = minix_inode->u.i1_data[i];
617	mark_buffer_dirty(bh);
618	return bh;
619}
620
621/*
622 * The minix V2 function to synchronize an inode.
623 */
624static struct buffer_head * V2_minix_update_inode(struct inode * inode)
625{
626	struct buffer_head * bh;
627	struct minix2_inode * raw_inode;
628	struct minix_inode_info *minix_inode = minix_i(inode);
629	int i;
630
631	raw_inode = minix_V2_raw_inode(inode->i_sb, inode->i_ino, &bh);
632	if (!raw_inode)
633		return NULL;
634	raw_inode->i_mode = inode->i_mode;
635	raw_inode->i_uid = fs_high2lowuid(i_uid_read(inode));
636	raw_inode->i_gid = fs_high2lowgid(i_gid_read(inode));
637	raw_inode->i_nlinks = inode->i_nlink;
638	raw_inode->i_size = inode->i_size;
639	raw_inode->i_mtime = inode_get_mtime_sec(inode);
640	raw_inode->i_atime = inode_get_atime_sec(inode);
641	raw_inode->i_ctime = inode_get_ctime_sec(inode);
642	if (S_ISCHR(inode->i_mode) || S_ISBLK(inode->i_mode))
643		raw_inode->i_zone[0] = old_encode_dev(inode->i_rdev);
644	else for (i = 0; i < 10; i++)
645		raw_inode->i_zone[i] = minix_inode->u.i2_data[i];
646	mark_buffer_dirty(bh);
647	return bh;
648}
649
650static int minix_write_inode(struct inode *inode, struct writeback_control *wbc)
651{
652	int err = 0;
653	struct buffer_head *bh;
654
655	if (INODE_VERSION(inode) == MINIX_V1)
656		bh = V1_minix_update_inode(inode);
657	else
658		bh = V2_minix_update_inode(inode);
659	if (!bh)
660		return -EIO;
661	if (wbc->sync_mode == WB_SYNC_ALL && buffer_dirty(bh)) {
662		sync_dirty_buffer(bh);
663		if (buffer_req(bh) && !buffer_uptodate(bh)) {
664			printk("IO error syncing minix inode [%s:%08lx]\n",
665				inode->i_sb->s_id, inode->i_ino);
666			err = -EIO;
667		}
668	}
669	brelse (bh);
670	return err;
671}
672
673int minix_getattr(struct mnt_idmap *idmap, const struct path *path,
674		  struct kstat *stat, u32 request_mask, unsigned int flags)
675{
676	struct super_block *sb = path->dentry->d_sb;
677	struct inode *inode = d_inode(path->dentry);
678
679	generic_fillattr(&nop_mnt_idmap, request_mask, inode, stat);
680	if (INODE_VERSION(inode) == MINIX_V1)
681		stat->blocks = (BLOCK_SIZE / 512) * V1_minix_blocks(stat->size, sb);
682	else
683		stat->blocks = (sb->s_blocksize / 512) * V2_minix_blocks(stat->size, sb);
684	stat->blksize = sb->s_blocksize;
685	return 0;
686}
687
688/*
689 * The function that is called for file truncation.
690 */
691void minix_truncate(struct inode * inode)
692{
693	if (!(S_ISREG(inode->i_mode) || S_ISDIR(inode->i_mode) || S_ISLNK(inode->i_mode)))
694		return;
695	if (INODE_VERSION(inode) == MINIX_V1)
696		V1_minix_truncate(inode);
697	else
698		V2_minix_truncate(inode);
699}
700
 
 
 
 
 
 
701static struct file_system_type minix_fs_type = {
702	.owner			= THIS_MODULE,
703	.name			= "minix",
704	.kill_sb		= kill_block_super,
705	.fs_flags		= FS_REQUIRES_DEV,
706	.init_fs_context	= minix_init_fs_context,
707};
708MODULE_ALIAS_FS("minix");
709
710static int __init init_minix_fs(void)
711{
712	int err = init_inodecache();
713	if (err)
714		goto out1;
715	err = register_filesystem(&minix_fs_type);
716	if (err)
717		goto out;
718	return 0;
719out:
720	destroy_inodecache();
721out1:
722	return err;
723}
724
725static void __exit exit_minix_fs(void)
726{
727        unregister_filesystem(&minix_fs_type);
728	destroy_inodecache();
729}
730
731module_init(init_minix_fs)
732module_exit(exit_minix_fs)
733MODULE_DESCRIPTION("Minix file system");
734MODULE_LICENSE("GPL");
735