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v3.15
 
  1/*
  2 *  linux/fs/minix/inode.c
  3 *
  4 *  Copyright (C) 1991, 1992  Linus Torvalds
  5 *
  6 *  Copyright (C) 1996  Gertjan van Wingerde
  7 *	Minix V2 fs support.
  8 *
  9 *  Modified for 680x0 by Andreas Schwab
 10 *  Updated to filesystem version 3 by Daniel Aragones
 11 */
 12
 13#include <linux/module.h>
 14#include "minix.h"
 15#include <linux/buffer_head.h>
 16#include <linux/slab.h>
 17#include <linux/init.h>
 18#include <linux/highuid.h>
 19#include <linux/vfs.h>
 20#include <linux/writeback.h>
 21
 22static int minix_write_inode(struct inode *inode,
 23		struct writeback_control *wbc);
 24static int minix_statfs(struct dentry *dentry, struct kstatfs *buf);
 25static int minix_remount (struct super_block * sb, int * flags, char * data);
 26
 27static void minix_evict_inode(struct inode *inode)
 28{
 29	truncate_inode_pages_final(&inode->i_data);
 30	if (!inode->i_nlink) {
 31		inode->i_size = 0;
 32		minix_truncate(inode);
 33	}
 34	invalidate_inode_buffers(inode);
 35	clear_inode(inode);
 36	if (!inode->i_nlink)
 37		minix_free_inode(inode);
 38}
 39
 40static void minix_put_super(struct super_block *sb)
 41{
 42	int i;
 43	struct minix_sb_info *sbi = minix_sb(sb);
 44
 45	if (!(sb->s_flags & MS_RDONLY)) {
 46		if (sbi->s_version != MINIX_V3)	 /* s_state is now out from V3 sb */
 47			sbi->s_ms->s_state = sbi->s_mount_state;
 48		mark_buffer_dirty(sbi->s_sbh);
 49	}
 50	for (i = 0; i < sbi->s_imap_blocks; i++)
 51		brelse(sbi->s_imap[i]);
 52	for (i = 0; i < sbi->s_zmap_blocks; i++)
 53		brelse(sbi->s_zmap[i]);
 54	brelse (sbi->s_sbh);
 55	kfree(sbi->s_imap);
 56	sb->s_fs_info = NULL;
 57	kfree(sbi);
 58}
 59
 60static struct kmem_cache * minix_inode_cachep;
 61
 62static struct inode *minix_alloc_inode(struct super_block *sb)
 63{
 64	struct minix_inode_info *ei;
 65	ei = (struct minix_inode_info *)kmem_cache_alloc(minix_inode_cachep, GFP_KERNEL);
 66	if (!ei)
 67		return NULL;
 68	return &ei->vfs_inode;
 69}
 70
 71static void minix_i_callback(struct rcu_head *head)
 72{
 73	struct inode *inode = container_of(head, struct inode, i_rcu);
 74	kmem_cache_free(minix_inode_cachep, minix_i(inode));
 75}
 76
 77static void minix_destroy_inode(struct inode *inode)
 78{
 79	call_rcu(&inode->i_rcu, minix_i_callback);
 80}
 81
 82static void init_once(void *foo)
 83{
 84	struct minix_inode_info *ei = (struct minix_inode_info *) foo;
 85
 86	inode_init_once(&ei->vfs_inode);
 87}
 88
 89static int __init init_inodecache(void)
 90{
 91	minix_inode_cachep = kmem_cache_create("minix_inode_cache",
 92					     sizeof(struct minix_inode_info),
 93					     0, (SLAB_RECLAIM_ACCOUNT|
 94						SLAB_MEM_SPREAD),
 95					     init_once);
 96	if (minix_inode_cachep == NULL)
 97		return -ENOMEM;
 98	return 0;
 99}
100
101static void destroy_inodecache(void)
102{
103	/*
104	 * Make sure all delayed rcu free inodes are flushed before we
105	 * destroy cache.
106	 */
107	rcu_barrier();
108	kmem_cache_destroy(minix_inode_cachep);
109}
110
111static const struct super_operations minix_sops = {
112	.alloc_inode	= minix_alloc_inode,
113	.destroy_inode	= minix_destroy_inode,
114	.write_inode	= minix_write_inode,
115	.evict_inode	= minix_evict_inode,
116	.put_super	= minix_put_super,
117	.statfs		= minix_statfs,
118	.remount_fs	= minix_remount,
119};
120
121static int minix_remount (struct super_block * sb, int * flags, char * data)
122{
123	struct minix_sb_info * sbi = minix_sb(sb);
124	struct minix_super_block * ms;
125
126	sync_filesystem(sb);
127	ms = sbi->s_ms;
128	if ((*flags & MS_RDONLY) == (sb->s_flags & MS_RDONLY))
129		return 0;
130	if (*flags & MS_RDONLY) {
131		if (ms->s_state & MINIX_VALID_FS ||
132		    !(sbi->s_mount_state & MINIX_VALID_FS))
133			return 0;
134		/* Mounting a rw partition read-only. */
135		if (sbi->s_version != MINIX_V3)
136			ms->s_state = sbi->s_mount_state;
137		mark_buffer_dirty(sbi->s_sbh);
138	} else {
139	  	/* Mount a partition which is read-only, read-write. */
140		if (sbi->s_version != MINIX_V3) {
141			sbi->s_mount_state = ms->s_state;
142			ms->s_state &= ~MINIX_VALID_FS;
143		} else {
144			sbi->s_mount_state = MINIX_VALID_FS;
145		}
146		mark_buffer_dirty(sbi->s_sbh);
147
148		if (!(sbi->s_mount_state & MINIX_VALID_FS))
149			printk("MINIX-fs warning: remounting unchecked fs, "
150				"running fsck is recommended\n");
151		else if ((sbi->s_mount_state & MINIX_ERROR_FS))
152			printk("MINIX-fs warning: remounting fs with errors, "
153				"running fsck is recommended\n");
154	}
155	return 0;
156}
157
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
158static int minix_fill_super(struct super_block *s, void *data, int silent)
159{
160	struct buffer_head *bh;
161	struct buffer_head **map;
162	struct minix_super_block *ms;
163	struct minix3_super_block *m3s = NULL;
164	unsigned long i, block;
165	struct inode *root_inode;
166	struct minix_sb_info *sbi;
167	int ret = -EINVAL;
168
169	sbi = kzalloc(sizeof(struct minix_sb_info), GFP_KERNEL);
170	if (!sbi)
171		return -ENOMEM;
172	s->s_fs_info = sbi;
173
174	BUILD_BUG_ON(32 != sizeof (struct minix_inode));
175	BUILD_BUG_ON(64 != sizeof(struct minix2_inode));
176
177	if (!sb_set_blocksize(s, BLOCK_SIZE))
178		goto out_bad_hblock;
179
180	if (!(bh = sb_bread(s, 1)))
181		goto out_bad_sb;
182
183	ms = (struct minix_super_block *) bh->b_data;
184	sbi->s_ms = ms;
185	sbi->s_sbh = bh;
186	sbi->s_mount_state = ms->s_state;
187	sbi->s_ninodes = ms->s_ninodes;
188	sbi->s_nzones = ms->s_nzones;
189	sbi->s_imap_blocks = ms->s_imap_blocks;
190	sbi->s_zmap_blocks = ms->s_zmap_blocks;
191	sbi->s_firstdatazone = ms->s_firstdatazone;
192	sbi->s_log_zone_size = ms->s_log_zone_size;
193	sbi->s_max_size = ms->s_max_size;
194	s->s_magic = ms->s_magic;
195	if (s->s_magic == MINIX_SUPER_MAGIC) {
196		sbi->s_version = MINIX_V1;
197		sbi->s_dirsize = 16;
198		sbi->s_namelen = 14;
199		s->s_max_links = MINIX_LINK_MAX;
200	} else if (s->s_magic == MINIX_SUPER_MAGIC2) {
201		sbi->s_version = MINIX_V1;
202		sbi->s_dirsize = 32;
203		sbi->s_namelen = 30;
204		s->s_max_links = MINIX_LINK_MAX;
205	} else if (s->s_magic == MINIX2_SUPER_MAGIC) {
206		sbi->s_version = MINIX_V2;
207		sbi->s_nzones = ms->s_zones;
208		sbi->s_dirsize = 16;
209		sbi->s_namelen = 14;
210		s->s_max_links = MINIX2_LINK_MAX;
211	} else if (s->s_magic == MINIX2_SUPER_MAGIC2) {
212		sbi->s_version = MINIX_V2;
213		sbi->s_nzones = ms->s_zones;
214		sbi->s_dirsize = 32;
215		sbi->s_namelen = 30;
216		s->s_max_links = MINIX2_LINK_MAX;
217	} else if ( *(__u16 *)(bh->b_data + 24) == MINIX3_SUPER_MAGIC) {
218		m3s = (struct minix3_super_block *) bh->b_data;
219		s->s_magic = m3s->s_magic;
220		sbi->s_imap_blocks = m3s->s_imap_blocks;
221		sbi->s_zmap_blocks = m3s->s_zmap_blocks;
222		sbi->s_firstdatazone = m3s->s_firstdatazone;
223		sbi->s_log_zone_size = m3s->s_log_zone_size;
224		sbi->s_max_size = m3s->s_max_size;
225		sbi->s_ninodes = m3s->s_ninodes;
226		sbi->s_nzones = m3s->s_zones;
227		sbi->s_dirsize = 64;
228		sbi->s_namelen = 60;
229		sbi->s_version = MINIX_V3;
230		sbi->s_mount_state = MINIX_VALID_FS;
231		sb_set_blocksize(s, m3s->s_blocksize);
232		s->s_max_links = MINIX2_LINK_MAX;
233	} else
234		goto out_no_fs;
235
 
 
 
236	/*
237	 * Allocate the buffer map to keep the superblock small.
238	 */
239	if (sbi->s_imap_blocks == 0 || sbi->s_zmap_blocks == 0)
240		goto out_illegal_sb;
241	i = (sbi->s_imap_blocks + sbi->s_zmap_blocks) * sizeof(bh);
242	map = kzalloc(i, GFP_KERNEL);
243	if (!map)
244		goto out_no_map;
245	sbi->s_imap = &map[0];
246	sbi->s_zmap = &map[sbi->s_imap_blocks];
247
248	block=2;
249	for (i=0 ; i < sbi->s_imap_blocks ; i++) {
250		if (!(sbi->s_imap[i]=sb_bread(s, block)))
251			goto out_no_bitmap;
252		block++;
253	}
254	for (i=0 ; i < sbi->s_zmap_blocks ; i++) {
255		if (!(sbi->s_zmap[i]=sb_bread(s, block)))
256			goto out_no_bitmap;
257		block++;
258	}
259
260	minix_set_bit(0,sbi->s_imap[0]->b_data);
261	minix_set_bit(0,sbi->s_zmap[0]->b_data);
262
263	/* Apparently minix can create filesystems that allocate more blocks for
264	 * the bitmaps than needed.  We simply ignore that, but verify it didn't
265	 * create one with not enough blocks and bail out if so.
266	 */
267	block = minix_blocks_needed(sbi->s_ninodes, s->s_blocksize);
268	if (sbi->s_imap_blocks < block) {
269		printk("MINIX-fs: file system does not have enough "
270				"imap blocks allocated.  Refusing to mount\n");
271		goto out_no_bitmap;
272	}
273
274	block = minix_blocks_needed(
275			(sbi->s_nzones - (sbi->s_firstdatazone + 1)),
276			s->s_blocksize);
277	if (sbi->s_zmap_blocks < block) {
278		printk("MINIX-fs: file system does not have enough "
279				"zmap blocks allocated.  Refusing to mount.\n");
280		goto out_no_bitmap;
281	}
282
283	/* set up enough so that it can read an inode */
284	s->s_op = &minix_sops;
 
 
285	root_inode = minix_iget(s, MINIX_ROOT_INO);
286	if (IS_ERR(root_inode)) {
287		ret = PTR_ERR(root_inode);
288		goto out_no_root;
289	}
290
291	ret = -ENOMEM;
292	s->s_root = d_make_root(root_inode);
293	if (!s->s_root)
294		goto out_no_root;
295
296	if (!(s->s_flags & MS_RDONLY)) {
297		if (sbi->s_version != MINIX_V3) /* s_state is now out from V3 sb */
298			ms->s_state &= ~MINIX_VALID_FS;
299		mark_buffer_dirty(bh);
300	}
301	if (!(sbi->s_mount_state & MINIX_VALID_FS))
302		printk("MINIX-fs: mounting unchecked file system, "
303			"running fsck is recommended\n");
304	else if (sbi->s_mount_state & MINIX_ERROR_FS)
305		printk("MINIX-fs: mounting file system with errors, "
306			"running fsck is recommended\n");
307
308	return 0;
309
310out_no_root:
311	if (!silent)
312		printk("MINIX-fs: get root inode failed\n");
313	goto out_freemap;
314
315out_no_bitmap:
316	printk("MINIX-fs: bad superblock or unable to read bitmaps\n");
317out_freemap:
318	for (i = 0; i < sbi->s_imap_blocks; i++)
319		brelse(sbi->s_imap[i]);
320	for (i = 0; i < sbi->s_zmap_blocks; i++)
321		brelse(sbi->s_zmap[i]);
322	kfree(sbi->s_imap);
323	goto out_release;
324
325out_no_map:
326	ret = -ENOMEM;
327	if (!silent)
328		printk("MINIX-fs: can't allocate map\n");
329	goto out_release;
330
331out_illegal_sb:
332	if (!silent)
333		printk("MINIX-fs: bad superblock\n");
334	goto out_release;
335
336out_no_fs:
337	if (!silent)
338		printk("VFS: Can't find a Minix filesystem V1 | V2 | V3 "
339		       "on device %s.\n", s->s_id);
340out_release:
341	brelse(bh);
342	goto out;
343
344out_bad_hblock:
345	printk("MINIX-fs: blocksize too small for device\n");
346	goto out;
347
348out_bad_sb:
349	printk("MINIX-fs: unable to read superblock\n");
350out:
351	s->s_fs_info = NULL;
352	kfree(sbi);
353	return ret;
354}
355
356static int minix_statfs(struct dentry *dentry, struct kstatfs *buf)
357{
358	struct super_block *sb = dentry->d_sb;
359	struct minix_sb_info *sbi = minix_sb(sb);
360	u64 id = huge_encode_dev(sb->s_bdev->bd_dev);
361	buf->f_type = sb->s_magic;
362	buf->f_bsize = sb->s_blocksize;
363	buf->f_blocks = (sbi->s_nzones - sbi->s_firstdatazone) << sbi->s_log_zone_size;
364	buf->f_bfree = minix_count_free_blocks(sb);
365	buf->f_bavail = buf->f_bfree;
366	buf->f_files = sbi->s_ninodes;
367	buf->f_ffree = minix_count_free_inodes(sb);
368	buf->f_namelen = sbi->s_namelen;
369	buf->f_fsid.val[0] = (u32)id;
370	buf->f_fsid.val[1] = (u32)(id >> 32);
371
372	return 0;
373}
374
375static int minix_get_block(struct inode *inode, sector_t block,
376		    struct buffer_head *bh_result, int create)
377{
378	if (INODE_VERSION(inode) == MINIX_V1)
379		return V1_minix_get_block(inode, block, bh_result, create);
380	else
381		return V2_minix_get_block(inode, block, bh_result, create);
382}
383
384static int minix_writepage(struct page *page, struct writeback_control *wbc)
385{
386	return block_write_full_page(page, minix_get_block, wbc);
387}
388
389static int minix_readpage(struct file *file, struct page *page)
390{
391	return block_read_full_page(page,minix_get_block);
392}
393
394int minix_prepare_chunk(struct page *page, loff_t pos, unsigned len)
395{
396	return __block_write_begin(page, pos, len, minix_get_block);
397}
398
399static void minix_write_failed(struct address_space *mapping, loff_t to)
400{
401	struct inode *inode = mapping->host;
402
403	if (to > inode->i_size) {
404		truncate_pagecache(inode, inode->i_size);
405		minix_truncate(inode);
406	}
407}
408
409static int minix_write_begin(struct file *file, struct address_space *mapping,
410			loff_t pos, unsigned len, unsigned flags,
411			struct page **pagep, void **fsdata)
412{
413	int ret;
414
415	ret = block_write_begin(mapping, pos, len, flags, pagep,
416				minix_get_block);
417	if (unlikely(ret))
418		minix_write_failed(mapping, pos + len);
419
420	return ret;
421}
422
423static sector_t minix_bmap(struct address_space *mapping, sector_t block)
424{
425	return generic_block_bmap(mapping,block,minix_get_block);
426}
427
428static const struct address_space_operations minix_aops = {
 
429	.readpage = minix_readpage,
430	.writepage = minix_writepage,
431	.write_begin = minix_write_begin,
432	.write_end = generic_write_end,
433	.bmap = minix_bmap
434};
435
436static const struct inode_operations minix_symlink_inode_operations = {
437	.readlink	= generic_readlink,
438	.follow_link	= page_follow_link_light,
439	.put_link	= page_put_link,
440	.getattr	= minix_getattr,
441};
442
443void minix_set_inode(struct inode *inode, dev_t rdev)
444{
445	if (S_ISREG(inode->i_mode)) {
446		inode->i_op = &minix_file_inode_operations;
447		inode->i_fop = &minix_file_operations;
448		inode->i_mapping->a_ops = &minix_aops;
449	} else if (S_ISDIR(inode->i_mode)) {
450		inode->i_op = &minix_dir_inode_operations;
451		inode->i_fop = &minix_dir_operations;
452		inode->i_mapping->a_ops = &minix_aops;
453	} else if (S_ISLNK(inode->i_mode)) {
454		inode->i_op = &minix_symlink_inode_operations;
 
455		inode->i_mapping->a_ops = &minix_aops;
456	} else
457		init_special_inode(inode, inode->i_mode, rdev);
458}
459
460/*
461 * The minix V1 function to read an inode.
462 */
463static struct inode *V1_minix_iget(struct inode *inode)
464{
465	struct buffer_head * bh;
466	struct minix_inode * raw_inode;
467	struct minix_inode_info *minix_inode = minix_i(inode);
468	int i;
469
470	raw_inode = minix_V1_raw_inode(inode->i_sb, inode->i_ino, &bh);
471	if (!raw_inode) {
472		iget_failed(inode);
473		return ERR_PTR(-EIO);
474	}
 
 
 
 
 
 
 
475	inode->i_mode = raw_inode->i_mode;
476	i_uid_write(inode, raw_inode->i_uid);
477	i_gid_write(inode, raw_inode->i_gid);
478	set_nlink(inode, raw_inode->i_nlinks);
479	inode->i_size = raw_inode->i_size;
480	inode->i_mtime.tv_sec = inode->i_atime.tv_sec = inode->i_ctime.tv_sec = raw_inode->i_time;
481	inode->i_mtime.tv_nsec = 0;
482	inode->i_atime.tv_nsec = 0;
483	inode->i_ctime.tv_nsec = 0;
484	inode->i_blocks = 0;
485	for (i = 0; i < 9; i++)
486		minix_inode->u.i1_data[i] = raw_inode->i_zone[i];
487	minix_set_inode(inode, old_decode_dev(raw_inode->i_zone[0]));
488	brelse(bh);
489	unlock_new_inode(inode);
490	return inode;
491}
492
493/*
494 * The minix V2 function to read an inode.
495 */
496static struct inode *V2_minix_iget(struct inode *inode)
497{
498	struct buffer_head * bh;
499	struct minix2_inode * raw_inode;
500	struct minix_inode_info *minix_inode = minix_i(inode);
501	int i;
502
503	raw_inode = minix_V2_raw_inode(inode->i_sb, inode->i_ino, &bh);
504	if (!raw_inode) {
505		iget_failed(inode);
506		return ERR_PTR(-EIO);
507	}
 
 
 
 
 
 
 
508	inode->i_mode = raw_inode->i_mode;
509	i_uid_write(inode, raw_inode->i_uid);
510	i_gid_write(inode, raw_inode->i_gid);
511	set_nlink(inode, raw_inode->i_nlinks);
512	inode->i_size = raw_inode->i_size;
513	inode->i_mtime.tv_sec = raw_inode->i_mtime;
514	inode->i_atime.tv_sec = raw_inode->i_atime;
515	inode->i_ctime.tv_sec = raw_inode->i_ctime;
516	inode->i_mtime.tv_nsec = 0;
517	inode->i_atime.tv_nsec = 0;
518	inode->i_ctime.tv_nsec = 0;
519	inode->i_blocks = 0;
520	for (i = 0; i < 10; i++)
521		minix_inode->u.i2_data[i] = raw_inode->i_zone[i];
522	minix_set_inode(inode, old_decode_dev(raw_inode->i_zone[0]));
523	brelse(bh);
524	unlock_new_inode(inode);
525	return inode;
526}
527
528/*
529 * The global function to read an inode.
530 */
531struct inode *minix_iget(struct super_block *sb, unsigned long ino)
532{
533	struct inode *inode;
534
535	inode = iget_locked(sb, ino);
536	if (!inode)
537		return ERR_PTR(-ENOMEM);
538	if (!(inode->i_state & I_NEW))
539		return inode;
540
541	if (INODE_VERSION(inode) == MINIX_V1)
542		return V1_minix_iget(inode);
543	else
544		return V2_minix_iget(inode);
545}
546
547/*
548 * The minix V1 function to synchronize an inode.
549 */
550static struct buffer_head * V1_minix_update_inode(struct inode * inode)
551{
552	struct buffer_head * bh;
553	struct minix_inode * raw_inode;
554	struct minix_inode_info *minix_inode = minix_i(inode);
555	int i;
556
557	raw_inode = minix_V1_raw_inode(inode->i_sb, inode->i_ino, &bh);
558	if (!raw_inode)
559		return NULL;
560	raw_inode->i_mode = inode->i_mode;
561	raw_inode->i_uid = fs_high2lowuid(i_uid_read(inode));
562	raw_inode->i_gid = fs_high2lowgid(i_gid_read(inode));
563	raw_inode->i_nlinks = inode->i_nlink;
564	raw_inode->i_size = inode->i_size;
565	raw_inode->i_time = inode->i_mtime.tv_sec;
566	if (S_ISCHR(inode->i_mode) || S_ISBLK(inode->i_mode))
567		raw_inode->i_zone[0] = old_encode_dev(inode->i_rdev);
568	else for (i = 0; i < 9; i++)
569		raw_inode->i_zone[i] = minix_inode->u.i1_data[i];
570	mark_buffer_dirty(bh);
571	return bh;
572}
573
574/*
575 * The minix V2 function to synchronize an inode.
576 */
577static struct buffer_head * V2_minix_update_inode(struct inode * inode)
578{
579	struct buffer_head * bh;
580	struct minix2_inode * raw_inode;
581	struct minix_inode_info *minix_inode = minix_i(inode);
582	int i;
583
584	raw_inode = minix_V2_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_mtime = inode->i_mtime.tv_sec;
593	raw_inode->i_atime = inode->i_atime.tv_sec;
594	raw_inode->i_ctime = inode->i_ctime.tv_sec;
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 < 10; i++)
598		raw_inode->i_zone[i] = minix_inode->u.i2_data[i];
599	mark_buffer_dirty(bh);
600	return bh;
601}
602
603static int minix_write_inode(struct inode *inode, struct writeback_control *wbc)
604{
605	int err = 0;
606	struct buffer_head *bh;
607
608	if (INODE_VERSION(inode) == MINIX_V1)
609		bh = V1_minix_update_inode(inode);
610	else
611		bh = V2_minix_update_inode(inode);
612	if (!bh)
613		return -EIO;
614	if (wbc->sync_mode == WB_SYNC_ALL && buffer_dirty(bh)) {
615		sync_dirty_buffer(bh);
616		if (buffer_req(bh) && !buffer_uptodate(bh)) {
617			printk("IO error syncing minix inode [%s:%08lx]\n",
618				inode->i_sb->s_id, inode->i_ino);
619			err = -EIO;
620		}
621	}
622	brelse (bh);
623	return err;
624}
625
626int minix_getattr(struct vfsmount *mnt, struct dentry *dentry, struct kstat *stat)
 
627{
628	struct super_block *sb = dentry->d_sb;
629	generic_fillattr(dentry->d_inode, stat);
630	if (INODE_VERSION(dentry->d_inode) == MINIX_V1)
 
 
631		stat->blocks = (BLOCK_SIZE / 512) * V1_minix_blocks(stat->size, sb);
632	else
633		stat->blocks = (sb->s_blocksize / 512) * V2_minix_blocks(stat->size, sb);
634	stat->blksize = sb->s_blocksize;
635	return 0;
636}
637
638/*
639 * The function that is called for file truncation.
640 */
641void minix_truncate(struct inode * inode)
642{
643	if (!(S_ISREG(inode->i_mode) || S_ISDIR(inode->i_mode) || S_ISLNK(inode->i_mode)))
644		return;
645	if (INODE_VERSION(inode) == MINIX_V1)
646		V1_minix_truncate(inode);
647	else
648		V2_minix_truncate(inode);
649}
650
651static struct dentry *minix_mount(struct file_system_type *fs_type,
652	int flags, const char *dev_name, void *data)
653{
654	return mount_bdev(fs_type, flags, dev_name, data, minix_fill_super);
655}
656
657static struct file_system_type minix_fs_type = {
658	.owner		= THIS_MODULE,
659	.name		= "minix",
660	.mount		= minix_mount,
661	.kill_sb	= kill_block_super,
662	.fs_flags	= FS_REQUIRES_DEV,
663};
664MODULE_ALIAS_FS("minix");
665
666static int __init init_minix_fs(void)
667{
668	int err = init_inodecache();
669	if (err)
670		goto out1;
671	err = register_filesystem(&minix_fs_type);
672	if (err)
673		goto out;
674	return 0;
675out:
676	destroy_inodecache();
677out1:
678	return err;
679}
680
681static void __exit exit_minix_fs(void)
682{
683        unregister_filesystem(&minix_fs_type);
684	destroy_inodecache();
685}
686
687module_init(init_minix_fs)
688module_exit(exit_minix_fs)
689MODULE_LICENSE("GPL");
690
v5.14.15
  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 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_readpage(struct file *file, struct page *page)
406{
407	return block_read_full_page(page,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, unsigned flags,
427			struct page **pagep, void **fsdata)
428{
429	int ret;
430
431	ret = block_write_begin(mapping, pos, len, flags, pagep,
432				minix_get_block);
433	if (unlikely(ret))
434		minix_write_failed(mapping, pos + len);
435
436	return ret;
437}
438
439static sector_t minix_bmap(struct address_space *mapping, sector_t block)
440{
441	return generic_block_bmap(mapping,block,minix_get_block);
442}
443
444static const struct address_space_operations minix_aops = {
445	.set_page_dirty	= __set_page_dirty_buffers,
446	.readpage = minix_readpage,
447	.writepage = minix_writepage,
448	.write_begin = minix_write_begin,
449	.write_end = generic_write_end,
450	.bmap = minix_bmap
451};
452
453static const struct inode_operations minix_symlink_inode_operations = {
454	.get_link	= page_get_link,
 
 
455	.getattr	= minix_getattr,
456};
457
458void minix_set_inode(struct inode *inode, dev_t rdev)
459{
460	if (S_ISREG(inode->i_mode)) {
461		inode->i_op = &minix_file_inode_operations;
462		inode->i_fop = &minix_file_operations;
463		inode->i_mapping->a_ops = &minix_aops;
464	} else if (S_ISDIR(inode->i_mode)) {
465		inode->i_op = &minix_dir_inode_operations;
466		inode->i_fop = &minix_dir_operations;
467		inode->i_mapping->a_ops = &minix_aops;
468	} else if (S_ISLNK(inode->i_mode)) {
469		inode->i_op = &minix_symlink_inode_operations;
470		inode_nohighmem(inode);
471		inode->i_mapping->a_ops = &minix_aops;
472	} else
473		init_special_inode(inode, inode->i_mode, rdev);
474}
475
476/*
477 * The minix V1 function to read an inode.
478 */
479static struct inode *V1_minix_iget(struct inode *inode)
480{
481	struct buffer_head * bh;
482	struct minix_inode * raw_inode;
483	struct minix_inode_info *minix_inode = minix_i(inode);
484	int i;
485
486	raw_inode = minix_V1_raw_inode(inode->i_sb, inode->i_ino, &bh);
487	if (!raw_inode) {
488		iget_failed(inode);
489		return ERR_PTR(-EIO);
490	}
491	if (raw_inode->i_nlinks == 0) {
492		printk("MINIX-fs: deleted inode referenced: %lu\n",
493		       inode->i_ino);
494		brelse(bh);
495		iget_failed(inode);
496		return ERR_PTR(-ESTALE);
497	}
498	inode->i_mode = raw_inode->i_mode;
499	i_uid_write(inode, raw_inode->i_uid);
500	i_gid_write(inode, raw_inode->i_gid);
501	set_nlink(inode, raw_inode->i_nlinks);
502	inode->i_size = raw_inode->i_size;
503	inode->i_mtime.tv_sec = inode->i_atime.tv_sec = inode->i_ctime.tv_sec = raw_inode->i_time;
504	inode->i_mtime.tv_nsec = 0;
505	inode->i_atime.tv_nsec = 0;
506	inode->i_ctime.tv_nsec = 0;
507	inode->i_blocks = 0;
508	for (i = 0; i < 9; i++)
509		minix_inode->u.i1_data[i] = raw_inode->i_zone[i];
510	minix_set_inode(inode, old_decode_dev(raw_inode->i_zone[0]));
511	brelse(bh);
512	unlock_new_inode(inode);
513	return inode;
514}
515
516/*
517 * The minix V2 function to read an inode.
518 */
519static struct inode *V2_minix_iget(struct inode *inode)
520{
521	struct buffer_head * bh;
522	struct minix2_inode * raw_inode;
523	struct minix_inode_info *minix_inode = minix_i(inode);
524	int i;
525
526	raw_inode = minix_V2_raw_inode(inode->i_sb, inode->i_ino, &bh);
527	if (!raw_inode) {
528		iget_failed(inode);
529		return ERR_PTR(-EIO);
530	}
531	if (raw_inode->i_nlinks == 0) {
532		printk("MINIX-fs: deleted inode referenced: %lu\n",
533		       inode->i_ino);
534		brelse(bh);
535		iget_failed(inode);
536		return ERR_PTR(-ESTALE);
537	}
538	inode->i_mode = raw_inode->i_mode;
539	i_uid_write(inode, raw_inode->i_uid);
540	i_gid_write(inode, raw_inode->i_gid);
541	set_nlink(inode, raw_inode->i_nlinks);
542	inode->i_size = raw_inode->i_size;
543	inode->i_mtime.tv_sec = raw_inode->i_mtime;
544	inode->i_atime.tv_sec = raw_inode->i_atime;
545	inode->i_ctime.tv_sec = raw_inode->i_ctime;
546	inode->i_mtime.tv_nsec = 0;
547	inode->i_atime.tv_nsec = 0;
548	inode->i_ctime.tv_nsec = 0;
549	inode->i_blocks = 0;
550	for (i = 0; i < 10; i++)
551		minix_inode->u.i2_data[i] = raw_inode->i_zone[i];
552	minix_set_inode(inode, old_decode_dev(raw_inode->i_zone[0]));
553	brelse(bh);
554	unlock_new_inode(inode);
555	return inode;
556}
557
558/*
559 * The global function to read an inode.
560 */
561struct inode *minix_iget(struct super_block *sb, unsigned long ino)
562{
563	struct inode *inode;
564
565	inode = iget_locked(sb, ino);
566	if (!inode)
567		return ERR_PTR(-ENOMEM);
568	if (!(inode->i_state & I_NEW))
569		return inode;
570
571	if (INODE_VERSION(inode) == MINIX_V1)
572		return V1_minix_iget(inode);
573	else
574		return V2_minix_iget(inode);
575}
576
577/*
578 * The minix V1 function to synchronize an inode.
579 */
580static struct buffer_head * V1_minix_update_inode(struct inode * inode)
581{
582	struct buffer_head * bh;
583	struct minix_inode * raw_inode;
584	struct minix_inode_info *minix_inode = minix_i(inode);
585	int i;
586
587	raw_inode = minix_V1_raw_inode(inode->i_sb, inode->i_ino, &bh);
588	if (!raw_inode)
589		return NULL;
590	raw_inode->i_mode = inode->i_mode;
591	raw_inode->i_uid = fs_high2lowuid(i_uid_read(inode));
592	raw_inode->i_gid = fs_high2lowgid(i_gid_read(inode));
593	raw_inode->i_nlinks = inode->i_nlink;
594	raw_inode->i_size = inode->i_size;
595	raw_inode->i_time = inode->i_mtime.tv_sec;
596	if (S_ISCHR(inode->i_mode) || S_ISBLK(inode->i_mode))
597		raw_inode->i_zone[0] = old_encode_dev(inode->i_rdev);
598	else for (i = 0; i < 9; i++)
599		raw_inode->i_zone[i] = minix_inode->u.i1_data[i];
600	mark_buffer_dirty(bh);
601	return bh;
602}
603
604/*
605 * The minix V2 function to synchronize an inode.
606 */
607static struct buffer_head * V2_minix_update_inode(struct inode * inode)
608{
609	struct buffer_head * bh;
610	struct minix2_inode * raw_inode;
611	struct minix_inode_info *minix_inode = minix_i(inode);
612	int i;
613
614	raw_inode = minix_V2_raw_inode(inode->i_sb, inode->i_ino, &bh);
615	if (!raw_inode)
616		return NULL;
617	raw_inode->i_mode = inode->i_mode;
618	raw_inode->i_uid = fs_high2lowuid(i_uid_read(inode));
619	raw_inode->i_gid = fs_high2lowgid(i_gid_read(inode));
620	raw_inode->i_nlinks = inode->i_nlink;
621	raw_inode->i_size = inode->i_size;
622	raw_inode->i_mtime = inode->i_mtime.tv_sec;
623	raw_inode->i_atime = inode->i_atime.tv_sec;
624	raw_inode->i_ctime = inode->i_ctime.tv_sec;
625	if (S_ISCHR(inode->i_mode) || S_ISBLK(inode->i_mode))
626		raw_inode->i_zone[0] = old_encode_dev(inode->i_rdev);
627	else for (i = 0; i < 10; i++)
628		raw_inode->i_zone[i] = minix_inode->u.i2_data[i];
629	mark_buffer_dirty(bh);
630	return bh;
631}
632
633static int minix_write_inode(struct inode *inode, struct writeback_control *wbc)
634{
635	int err = 0;
636	struct buffer_head *bh;
637
638	if (INODE_VERSION(inode) == MINIX_V1)
639		bh = V1_minix_update_inode(inode);
640	else
641		bh = V2_minix_update_inode(inode);
642	if (!bh)
643		return -EIO;
644	if (wbc->sync_mode == WB_SYNC_ALL && buffer_dirty(bh)) {
645		sync_dirty_buffer(bh);
646		if (buffer_req(bh) && !buffer_uptodate(bh)) {
647			printk("IO error syncing minix inode [%s:%08lx]\n",
648				inode->i_sb->s_id, inode->i_ino);
649			err = -EIO;
650		}
651	}
652	brelse (bh);
653	return err;
654}
655
656int minix_getattr(struct user_namespace *mnt_userns, const struct path *path,
657		  struct kstat *stat, u32 request_mask, unsigned int flags)
658{
659	struct super_block *sb = path->dentry->d_sb;
660	struct inode *inode = d_inode(path->dentry);
661
662	generic_fillattr(&init_user_ns, inode, stat);
663	if (INODE_VERSION(inode) == MINIX_V1)
664		stat->blocks = (BLOCK_SIZE / 512) * V1_minix_blocks(stat->size, sb);
665	else
666		stat->blocks = (sb->s_blocksize / 512) * V2_minix_blocks(stat->size, sb);
667	stat->blksize = sb->s_blocksize;
668	return 0;
669}
670
671/*
672 * The function that is called for file truncation.
673 */
674void minix_truncate(struct inode * inode)
675{
676	if (!(S_ISREG(inode->i_mode) || S_ISDIR(inode->i_mode) || S_ISLNK(inode->i_mode)))
677		return;
678	if (INODE_VERSION(inode) == MINIX_V1)
679		V1_minix_truncate(inode);
680	else
681		V2_minix_truncate(inode);
682}
683
684static struct dentry *minix_mount(struct file_system_type *fs_type,
685	int flags, const char *dev_name, void *data)
686{
687	return mount_bdev(fs_type, flags, dev_name, data, minix_fill_super);
688}
689
690static struct file_system_type minix_fs_type = {
691	.owner		= THIS_MODULE,
692	.name		= "minix",
693	.mount		= minix_mount,
694	.kill_sb	= kill_block_super,
695	.fs_flags	= FS_REQUIRES_DEV,
696};
697MODULE_ALIAS_FS("minix");
698
699static int __init init_minix_fs(void)
700{
701	int err = init_inodecache();
702	if (err)
703		goto out1;
704	err = register_filesystem(&minix_fs_type);
705	if (err)
706		goto out;
707	return 0;
708out:
709	destroy_inodecache();
710out1:
711	return err;
712}
713
714static void __exit exit_minix_fs(void)
715{
716        unregister_filesystem(&minix_fs_type);
717	destroy_inodecache();
718}
719
720module_init(init_minix_fs)
721module_exit(exit_minix_fs)
722MODULE_LICENSE("GPL");
723