Loading...
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(&inode->i_data, 0);
30 if (!inode->i_nlink) {
31 inode->i_size = 0;
32 minix_truncate(inode);
33 }
34 invalidate_inode_buffers(inode);
35 end_writeback(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 INIT_LIST_HEAD(&inode->i_dentry);
75 kmem_cache_free(minix_inode_cachep, minix_i(inode));
76}
77
78static void minix_destroy_inode(struct inode *inode)
79{
80 call_rcu(&inode->i_rcu, minix_i_callback);
81}
82
83static void init_once(void *foo)
84{
85 struct minix_inode_info *ei = (struct minix_inode_info *) foo;
86
87 inode_init_once(&ei->vfs_inode);
88}
89
90static int init_inodecache(void)
91{
92 minix_inode_cachep = kmem_cache_create("minix_inode_cache",
93 sizeof(struct minix_inode_info),
94 0, (SLAB_RECLAIM_ACCOUNT|
95 SLAB_MEM_SPREAD),
96 init_once);
97 if (minix_inode_cachep == NULL)
98 return -ENOMEM;
99 return 0;
100}
101
102static void destroy_inodecache(void)
103{
104 kmem_cache_destroy(minix_inode_cachep);
105}
106
107static const struct super_operations minix_sops = {
108 .alloc_inode = minix_alloc_inode,
109 .destroy_inode = minix_destroy_inode,
110 .write_inode = minix_write_inode,
111 .evict_inode = minix_evict_inode,
112 .put_super = minix_put_super,
113 .statfs = minix_statfs,
114 .remount_fs = minix_remount,
115};
116
117static int minix_remount (struct super_block * sb, int * flags, char * data)
118{
119 struct minix_sb_info * sbi = minix_sb(sb);
120 struct minix_super_block * ms;
121
122 ms = sbi->s_ms;
123 if ((*flags & MS_RDONLY) == (sb->s_flags & MS_RDONLY))
124 return 0;
125 if (*flags & MS_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 sbi->s_link_max = 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 sbi->s_link_max = 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 sbi->s_link_max = 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 sbi->s_link_max = 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_link_max = MINIX2_LINK_MAX;
226 sbi->s_mount_state = MINIX_VALID_FS;
227 sb_set_blocksize(s, m3s->s_blocksize);
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 /* set up enough so that it can read an inode */
259 s->s_op = &minix_sops;
260 root_inode = minix_iget(s, MINIX_ROOT_INO);
261 if (IS_ERR(root_inode)) {
262 ret = PTR_ERR(root_inode);
263 goto out_no_root;
264 }
265
266 ret = -ENOMEM;
267 s->s_root = d_alloc_root(root_inode);
268 if (!s->s_root)
269 goto out_iput;
270
271 if (!(s->s_flags & MS_RDONLY)) {
272 if (sbi->s_version != MINIX_V3) /* s_state is now out from V3 sb */
273 ms->s_state &= ~MINIX_VALID_FS;
274 mark_buffer_dirty(bh);
275 }
276 if (!(sbi->s_mount_state & MINIX_VALID_FS))
277 printk("MINIX-fs: mounting unchecked file system, "
278 "running fsck is recommended\n");
279 else if (sbi->s_mount_state & MINIX_ERROR_FS)
280 printk("MINIX-fs: mounting file system with errors, "
281 "running fsck is recommended\n");
282 return 0;
283
284out_iput:
285 iput(root_inode);
286 goto out_freemap;
287
288out_no_root:
289 if (!silent)
290 printk("MINIX-fs: get root inode failed\n");
291 goto out_freemap;
292
293out_no_bitmap:
294 printk("MINIX-fs: bad superblock or unable to read bitmaps\n");
295out_freemap:
296 for (i = 0; i < sbi->s_imap_blocks; i++)
297 brelse(sbi->s_imap[i]);
298 for (i = 0; i < sbi->s_zmap_blocks; i++)
299 brelse(sbi->s_zmap[i]);
300 kfree(sbi->s_imap);
301 goto out_release;
302
303out_no_map:
304 ret = -ENOMEM;
305 if (!silent)
306 printk("MINIX-fs: can't allocate map\n");
307 goto out_release;
308
309out_illegal_sb:
310 if (!silent)
311 printk("MINIX-fs: bad superblock\n");
312 goto out_release;
313
314out_no_fs:
315 if (!silent)
316 printk("VFS: Can't find a Minix filesystem V1 | V2 | V3 "
317 "on device %s.\n", s->s_id);
318out_release:
319 brelse(bh);
320 goto out;
321
322out_bad_hblock:
323 printk("MINIX-fs: blocksize too small for device\n");
324 goto out;
325
326out_bad_sb:
327 printk("MINIX-fs: unable to read superblock\n");
328out:
329 s->s_fs_info = NULL;
330 kfree(sbi);
331 return ret;
332}
333
334static int minix_statfs(struct dentry *dentry, struct kstatfs *buf)
335{
336 struct super_block *sb = dentry->d_sb;
337 struct minix_sb_info *sbi = minix_sb(sb);
338 u64 id = huge_encode_dev(sb->s_bdev->bd_dev);
339 buf->f_type = sb->s_magic;
340 buf->f_bsize = sb->s_blocksize;
341 buf->f_blocks = (sbi->s_nzones - sbi->s_firstdatazone) << sbi->s_log_zone_size;
342 buf->f_bfree = minix_count_free_blocks(sbi);
343 buf->f_bavail = buf->f_bfree;
344 buf->f_files = sbi->s_ninodes;
345 buf->f_ffree = minix_count_free_inodes(sbi);
346 buf->f_namelen = sbi->s_namelen;
347 buf->f_fsid.val[0] = (u32)id;
348 buf->f_fsid.val[1] = (u32)(id >> 32);
349
350 return 0;
351}
352
353static int minix_get_block(struct inode *inode, sector_t block,
354 struct buffer_head *bh_result, int create)
355{
356 if (INODE_VERSION(inode) == MINIX_V1)
357 return V1_minix_get_block(inode, block, bh_result, create);
358 else
359 return V2_minix_get_block(inode, block, bh_result, create);
360}
361
362static int minix_writepage(struct page *page, struct writeback_control *wbc)
363{
364 return block_write_full_page(page, minix_get_block, wbc);
365}
366
367static int minix_readpage(struct file *file, struct page *page)
368{
369 return block_read_full_page(page,minix_get_block);
370}
371
372int minix_prepare_chunk(struct page *page, loff_t pos, unsigned len)
373{
374 return __block_write_begin(page, pos, len, minix_get_block);
375}
376
377static int minix_write_begin(struct file *file, struct address_space *mapping,
378 loff_t pos, unsigned len, unsigned flags,
379 struct page **pagep, void **fsdata)
380{
381 int ret;
382
383 ret = block_write_begin(mapping, pos, len, flags, pagep,
384 minix_get_block);
385 if (unlikely(ret)) {
386 loff_t isize = mapping->host->i_size;
387 if (pos + len > isize)
388 vmtruncate(mapping->host, isize);
389 }
390
391 return ret;
392}
393
394static sector_t minix_bmap(struct address_space *mapping, sector_t block)
395{
396 return generic_block_bmap(mapping,block,minix_get_block);
397}
398
399static const struct address_space_operations minix_aops = {
400 .readpage = minix_readpage,
401 .writepage = minix_writepage,
402 .write_begin = minix_write_begin,
403 .write_end = generic_write_end,
404 .bmap = minix_bmap
405};
406
407static const struct inode_operations minix_symlink_inode_operations = {
408 .readlink = generic_readlink,
409 .follow_link = page_follow_link_light,
410 .put_link = page_put_link,
411 .getattr = minix_getattr,
412};
413
414void minix_set_inode(struct inode *inode, dev_t rdev)
415{
416 if (S_ISREG(inode->i_mode)) {
417 inode->i_op = &minix_file_inode_operations;
418 inode->i_fop = &minix_file_operations;
419 inode->i_mapping->a_ops = &minix_aops;
420 } else if (S_ISDIR(inode->i_mode)) {
421 inode->i_op = &minix_dir_inode_operations;
422 inode->i_fop = &minix_dir_operations;
423 inode->i_mapping->a_ops = &minix_aops;
424 } else if (S_ISLNK(inode->i_mode)) {
425 inode->i_op = &minix_symlink_inode_operations;
426 inode->i_mapping->a_ops = &minix_aops;
427 } else
428 init_special_inode(inode, inode->i_mode, rdev);
429}
430
431/*
432 * The minix V1 function to read an inode.
433 */
434static struct inode *V1_minix_iget(struct inode *inode)
435{
436 struct buffer_head * bh;
437 struct minix_inode * raw_inode;
438 struct minix_inode_info *minix_inode = minix_i(inode);
439 int i;
440
441 raw_inode = minix_V1_raw_inode(inode->i_sb, inode->i_ino, &bh);
442 if (!raw_inode) {
443 iget_failed(inode);
444 return ERR_PTR(-EIO);
445 }
446 inode->i_mode = raw_inode->i_mode;
447 inode->i_uid = (uid_t)raw_inode->i_uid;
448 inode->i_gid = (gid_t)raw_inode->i_gid;
449 inode->i_nlink = raw_inode->i_nlinks;
450 inode->i_size = raw_inode->i_size;
451 inode->i_mtime.tv_sec = inode->i_atime.tv_sec = inode->i_ctime.tv_sec = raw_inode->i_time;
452 inode->i_mtime.tv_nsec = 0;
453 inode->i_atime.tv_nsec = 0;
454 inode->i_ctime.tv_nsec = 0;
455 inode->i_blocks = 0;
456 for (i = 0; i < 9; i++)
457 minix_inode->u.i1_data[i] = raw_inode->i_zone[i];
458 minix_set_inode(inode, old_decode_dev(raw_inode->i_zone[0]));
459 brelse(bh);
460 unlock_new_inode(inode);
461 return inode;
462}
463
464/*
465 * The minix V2 function to read an inode.
466 */
467static struct inode *V2_minix_iget(struct inode *inode)
468{
469 struct buffer_head * bh;
470 struct minix2_inode * raw_inode;
471 struct minix_inode_info *minix_inode = minix_i(inode);
472 int i;
473
474 raw_inode = minix_V2_raw_inode(inode->i_sb, inode->i_ino, &bh);
475 if (!raw_inode) {
476 iget_failed(inode);
477 return ERR_PTR(-EIO);
478 }
479 inode->i_mode = raw_inode->i_mode;
480 inode->i_uid = (uid_t)raw_inode->i_uid;
481 inode->i_gid = (gid_t)raw_inode->i_gid;
482 inode->i_nlink = raw_inode->i_nlinks;
483 inode->i_size = raw_inode->i_size;
484 inode->i_mtime.tv_sec = raw_inode->i_mtime;
485 inode->i_atime.tv_sec = raw_inode->i_atime;
486 inode->i_ctime.tv_sec = raw_inode->i_ctime;
487 inode->i_mtime.tv_nsec = 0;
488 inode->i_atime.tv_nsec = 0;
489 inode->i_ctime.tv_nsec = 0;
490 inode->i_blocks = 0;
491 for (i = 0; i < 10; i++)
492 minix_inode->u.i2_data[i] = raw_inode->i_zone[i];
493 minix_set_inode(inode, old_decode_dev(raw_inode->i_zone[0]));
494 brelse(bh);
495 unlock_new_inode(inode);
496 return inode;
497}
498
499/*
500 * The global function to read an inode.
501 */
502struct inode *minix_iget(struct super_block *sb, unsigned long ino)
503{
504 struct inode *inode;
505
506 inode = iget_locked(sb, ino);
507 if (!inode)
508 return ERR_PTR(-ENOMEM);
509 if (!(inode->i_state & I_NEW))
510 return inode;
511
512 if (INODE_VERSION(inode) == MINIX_V1)
513 return V1_minix_iget(inode);
514 else
515 return V2_minix_iget(inode);
516}
517
518/*
519 * The minix V1 function to synchronize an inode.
520 */
521static struct buffer_head * V1_minix_update_inode(struct inode * inode)
522{
523 struct buffer_head * bh;
524 struct minix_inode * raw_inode;
525 struct minix_inode_info *minix_inode = minix_i(inode);
526 int i;
527
528 raw_inode = minix_V1_raw_inode(inode->i_sb, inode->i_ino, &bh);
529 if (!raw_inode)
530 return NULL;
531 raw_inode->i_mode = inode->i_mode;
532 raw_inode->i_uid = fs_high2lowuid(inode->i_uid);
533 raw_inode->i_gid = fs_high2lowgid(inode->i_gid);
534 raw_inode->i_nlinks = inode->i_nlink;
535 raw_inode->i_size = inode->i_size;
536 raw_inode->i_time = inode->i_mtime.tv_sec;
537 if (S_ISCHR(inode->i_mode) || S_ISBLK(inode->i_mode))
538 raw_inode->i_zone[0] = old_encode_dev(inode->i_rdev);
539 else for (i = 0; i < 9; i++)
540 raw_inode->i_zone[i] = minix_inode->u.i1_data[i];
541 mark_buffer_dirty(bh);
542 return bh;
543}
544
545/*
546 * The minix V2 function to synchronize an inode.
547 */
548static struct buffer_head * V2_minix_update_inode(struct inode * inode)
549{
550 struct buffer_head * bh;
551 struct minix2_inode * raw_inode;
552 struct minix_inode_info *minix_inode = minix_i(inode);
553 int i;
554
555 raw_inode = minix_V2_raw_inode(inode->i_sb, inode->i_ino, &bh);
556 if (!raw_inode)
557 return NULL;
558 raw_inode->i_mode = inode->i_mode;
559 raw_inode->i_uid = fs_high2lowuid(inode->i_uid);
560 raw_inode->i_gid = fs_high2lowgid(inode->i_gid);
561 raw_inode->i_nlinks = inode->i_nlink;
562 raw_inode->i_size = inode->i_size;
563 raw_inode->i_mtime = inode->i_mtime.tv_sec;
564 raw_inode->i_atime = inode->i_atime.tv_sec;
565 raw_inode->i_ctime = inode->i_ctime.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 < 10; i++)
569 raw_inode->i_zone[i] = minix_inode->u.i2_data[i];
570 mark_buffer_dirty(bh);
571 return bh;
572}
573
574static int minix_write_inode(struct inode *inode, struct writeback_control *wbc)
575{
576 int err = 0;
577 struct buffer_head *bh;
578
579 if (INODE_VERSION(inode) == MINIX_V1)
580 bh = V1_minix_update_inode(inode);
581 else
582 bh = V2_minix_update_inode(inode);
583 if (!bh)
584 return -EIO;
585 if (wbc->sync_mode == WB_SYNC_ALL && buffer_dirty(bh)) {
586 sync_dirty_buffer(bh);
587 if (buffer_req(bh) && !buffer_uptodate(bh)) {
588 printk("IO error syncing minix inode [%s:%08lx]\n",
589 inode->i_sb->s_id, inode->i_ino);
590 err = -EIO;
591 }
592 }
593 brelse (bh);
594 return err;
595}
596
597int minix_getattr(struct vfsmount *mnt, struct dentry *dentry, struct kstat *stat)
598{
599 struct super_block *sb = dentry->d_sb;
600 generic_fillattr(dentry->d_inode, stat);
601 if (INODE_VERSION(dentry->d_inode) == MINIX_V1)
602 stat->blocks = (BLOCK_SIZE / 512) * V1_minix_blocks(stat->size, sb);
603 else
604 stat->blocks = (sb->s_blocksize / 512) * V2_minix_blocks(stat->size, sb);
605 stat->blksize = sb->s_blocksize;
606 return 0;
607}
608
609/*
610 * The function that is called for file truncation.
611 */
612void minix_truncate(struct inode * inode)
613{
614 if (!(S_ISREG(inode->i_mode) || S_ISDIR(inode->i_mode) || S_ISLNK(inode->i_mode)))
615 return;
616 if (INODE_VERSION(inode) == MINIX_V1)
617 V1_minix_truncate(inode);
618 else
619 V2_minix_truncate(inode);
620}
621
622static struct dentry *minix_mount(struct file_system_type *fs_type,
623 int flags, const char *dev_name, void *data)
624{
625 return mount_bdev(fs_type, flags, dev_name, data, minix_fill_super);
626}
627
628static struct file_system_type minix_fs_type = {
629 .owner = THIS_MODULE,
630 .name = "minix",
631 .mount = minix_mount,
632 .kill_sb = kill_block_super,
633 .fs_flags = FS_REQUIRES_DEV,
634};
635
636static int __init init_minix_fs(void)
637{
638 int err = init_inodecache();
639 if (err)
640 goto out1;
641 err = register_filesystem(&minix_fs_type);
642 if (err)
643 goto out;
644 return 0;
645out:
646 destroy_inodecache();
647out1:
648 return err;
649}
650
651static void __exit exit_minix_fs(void)
652{
653 unregister_filesystem(&minix_fs_type);
654 destroy_inodecache();
655}
656
657module_init(init_minix_fs)
658module_exit(exit_minix_fs)
659MODULE_LICENSE("GPL");
660
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