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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
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