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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
24static int minix_write_inode(struct inode *inode,
25 struct writeback_control *wbc);
26static int minix_statfs(struct dentry *dentry, struct kstatfs *buf);
27static int minix_remount (struct super_block * sb, int * flags, char * data);
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_MEM_SPREAD|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 .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 sync_filesystem(sb);
123 ms = sbi->s_ms;
124 if ((bool)(*flags & SB_RDONLY) == sb_rdonly(sb))
125 return 0;
126 if (*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, void *data, int silent)
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
184 sbi = kzalloc(sizeof(struct minix_sb_info), GFP_KERNEL);
185 if (!sbi)
186 return -ENOMEM;
187 s->s_fs_info = sbi;
188
189 BUILD_BUG_ON(32 != sizeof (struct minix_inode));
190 BUILD_BUG_ON(64 != sizeof(struct minix2_inode));
191
192 if (!sb_set_blocksize(s, BLOCK_SIZE))
193 goto out_bad_hblock;
194
195 if (!(bh = sb_bread(s, 1)))
196 goto out_bad_sb;
197
198 ms = (struct minix_super_block *) bh->b_data;
199 sbi->s_ms = ms;
200 sbi->s_sbh = bh;
201 sbi->s_mount_state = ms->s_state;
202 sbi->s_ninodes = ms->s_ninodes;
203 sbi->s_nzones = ms->s_nzones;
204 sbi->s_imap_blocks = ms->s_imap_blocks;
205 sbi->s_zmap_blocks = ms->s_zmap_blocks;
206 sbi->s_firstdatazone = ms->s_firstdatazone;
207 sbi->s_log_zone_size = ms->s_log_zone_size;
208 s->s_maxbytes = ms->s_max_size;
209 s->s_magic = ms->s_magic;
210 if (s->s_magic == MINIX_SUPER_MAGIC) {
211 sbi->s_version = MINIX_V1;
212 sbi->s_dirsize = 16;
213 sbi->s_namelen = 14;
214 s->s_max_links = MINIX_LINK_MAX;
215 } else if (s->s_magic == MINIX_SUPER_MAGIC2) {
216 sbi->s_version = MINIX_V1;
217 sbi->s_dirsize = 32;
218 sbi->s_namelen = 30;
219 s->s_max_links = MINIX_LINK_MAX;
220 } else if (s->s_magic == MINIX2_SUPER_MAGIC) {
221 sbi->s_version = MINIX_V2;
222 sbi->s_nzones = ms->s_zones;
223 sbi->s_dirsize = 16;
224 sbi->s_namelen = 14;
225 s->s_max_links = MINIX2_LINK_MAX;
226 } else if (s->s_magic == MINIX2_SUPER_MAGIC2) {
227 sbi->s_version = MINIX_V2;
228 sbi->s_nzones = ms->s_zones;
229 sbi->s_dirsize = 32;
230 sbi->s_namelen = 30;
231 s->s_max_links = MINIX2_LINK_MAX;
232 } else if ( *(__u16 *)(bh->b_data + 24) == MINIX3_SUPER_MAGIC) {
233 m3s = (struct minix3_super_block *) bh->b_data;
234 s->s_magic = m3s->s_magic;
235 sbi->s_imap_blocks = m3s->s_imap_blocks;
236 sbi->s_zmap_blocks = m3s->s_zmap_blocks;
237 sbi->s_firstdatazone = m3s->s_firstdatazone;
238 sbi->s_log_zone_size = m3s->s_log_zone_size;
239 s->s_maxbytes = m3s->s_max_size;
240 sbi->s_ninodes = m3s->s_ninodes;
241 sbi->s_nzones = m3s->s_zones;
242 sbi->s_dirsize = 64;
243 sbi->s_namelen = 60;
244 sbi->s_version = MINIX_V3;
245 sbi->s_mount_state = MINIX_VALID_FS;
246 sb_set_blocksize(s, m3s->s_blocksize);
247 s->s_max_links = MINIX2_LINK_MAX;
248 } else
249 goto out_no_fs;
250
251 if (!minix_check_superblock(s))
252 goto out_illegal_sb;
253
254 /*
255 * Allocate the buffer map to keep the superblock small.
256 */
257 i = (sbi->s_imap_blocks + sbi->s_zmap_blocks) * sizeof(bh);
258 map = kzalloc(i, GFP_KERNEL);
259 if (!map)
260 goto out_no_map;
261 sbi->s_imap = &map[0];
262 sbi->s_zmap = &map[sbi->s_imap_blocks];
263
264 block=2;
265 for (i=0 ; i < sbi->s_imap_blocks ; i++) {
266 if (!(sbi->s_imap[i]=sb_bread(s, block)))
267 goto out_no_bitmap;
268 block++;
269 }
270 for (i=0 ; i < sbi->s_zmap_blocks ; i++) {
271 if (!(sbi->s_zmap[i]=sb_bread(s, block)))
272 goto out_no_bitmap;
273 block++;
274 }
275
276 minix_set_bit(0,sbi->s_imap[0]->b_data);
277 minix_set_bit(0,sbi->s_zmap[0]->b_data);
278
279 /* Apparently minix can create filesystems that allocate more blocks for
280 * the bitmaps than needed. We simply ignore that, but verify it didn't
281 * create one with not enough blocks and bail out if so.
282 */
283 block = minix_blocks_needed(sbi->s_ninodes, s->s_blocksize);
284 if (sbi->s_imap_blocks < block) {
285 printk("MINIX-fs: file system does not have enough "
286 "imap blocks allocated. Refusing to mount.\n");
287 goto out_no_bitmap;
288 }
289
290 block = minix_blocks_needed(
291 (sbi->s_nzones - sbi->s_firstdatazone + 1),
292 s->s_blocksize);
293 if (sbi->s_zmap_blocks < block) {
294 printk("MINIX-fs: file system does not have enough "
295 "zmap blocks allocated. Refusing to mount.\n");
296 goto out_no_bitmap;
297 }
298
299 /* set up enough so that it can read an inode */
300 s->s_op = &minix_sops;
301 s->s_time_min = 0;
302 s->s_time_max = U32_MAX;
303 root_inode = minix_iget(s, MINIX_ROOT_INO);
304 if (IS_ERR(root_inode)) {
305 ret = PTR_ERR(root_inode);
306 goto out_no_root;
307 }
308
309 ret = -ENOMEM;
310 s->s_root = d_make_root(root_inode);
311 if (!s->s_root)
312 goto out_no_root;
313
314 if (!sb_rdonly(s)) {
315 if (sbi->s_version != MINIX_V3) /* s_state is now out from V3 sb */
316 ms->s_state &= ~MINIX_VALID_FS;
317 mark_buffer_dirty(bh);
318 }
319 if (!(sbi->s_mount_state & MINIX_VALID_FS))
320 printk("MINIX-fs: mounting unchecked file system, "
321 "running fsck is recommended\n");
322 else if (sbi->s_mount_state & MINIX_ERROR_FS)
323 printk("MINIX-fs: mounting file system with errors, "
324 "running fsck is recommended\n");
325
326 return 0;
327
328out_no_root:
329 if (!silent)
330 printk("MINIX-fs: get root inode failed\n");
331 goto out_freemap;
332
333out_no_bitmap:
334 printk("MINIX-fs: bad superblock or unable to read bitmaps\n");
335out_freemap:
336 for (i = 0; i < sbi->s_imap_blocks; i++)
337 brelse(sbi->s_imap[i]);
338 for (i = 0; i < sbi->s_zmap_blocks; i++)
339 brelse(sbi->s_zmap[i]);
340 kfree(sbi->s_imap);
341 goto out_release;
342
343out_no_map:
344 ret = -ENOMEM;
345 if (!silent)
346 printk("MINIX-fs: can't allocate map\n");
347 goto out_release;
348
349out_illegal_sb:
350 if (!silent)
351 printk("MINIX-fs: bad superblock\n");
352 goto out_release;
353
354out_no_fs:
355 if (!silent)
356 printk("VFS: Can't find a Minix filesystem V1 | V2 | V3 "
357 "on device %s.\n", s->s_id);
358out_release:
359 brelse(bh);
360 goto out;
361
362out_bad_hblock:
363 printk("MINIX-fs: blocksize too small for device\n");
364 goto out;
365
366out_bad_sb:
367 printk("MINIX-fs: unable to read superblock\n");
368out:
369 s->s_fs_info = NULL;
370 kfree(sbi);
371 return ret;
372}
373
374static int minix_statfs(struct dentry *dentry, struct kstatfs *buf)
375{
376 struct super_block *sb = dentry->d_sb;
377 struct minix_sb_info *sbi = minix_sb(sb);
378 u64 id = huge_encode_dev(sb->s_bdev->bd_dev);
379 buf->f_type = sb->s_magic;
380 buf->f_bsize = sb->s_blocksize;
381 buf->f_blocks = (sbi->s_nzones - sbi->s_firstdatazone) << sbi->s_log_zone_size;
382 buf->f_bfree = minix_count_free_blocks(sb);
383 buf->f_bavail = buf->f_bfree;
384 buf->f_files = sbi->s_ninodes;
385 buf->f_ffree = minix_count_free_inodes(sb);
386 buf->f_namelen = sbi->s_namelen;
387 buf->f_fsid = u64_to_fsid(id);
388
389 return 0;
390}
391
392static int minix_get_block(struct inode *inode, sector_t block,
393 struct buffer_head *bh_result, int create)
394{
395 if (INODE_VERSION(inode) == MINIX_V1)
396 return V1_minix_get_block(inode, block, bh_result, create);
397 else
398 return V2_minix_get_block(inode, block, bh_result, create);
399}
400
401static int minix_writepages(struct address_space *mapping,
402 struct writeback_control *wbc)
403{
404 return mpage_writepages(mapping, wbc, minix_get_block);
405}
406
407static int minix_read_folio(struct file *file, struct folio *folio)
408{
409 return block_read_full_folio(folio, minix_get_block);
410}
411
412int minix_prepare_chunk(struct page *page, loff_t pos, unsigned len)
413{
414 return __block_write_begin(page, pos, len, minix_get_block);
415}
416
417static void minix_write_failed(struct address_space *mapping, loff_t to)
418{
419 struct inode *inode = mapping->host;
420
421 if (to > inode->i_size) {
422 truncate_pagecache(inode, inode->i_size);
423 minix_truncate(inode);
424 }
425}
426
427static int minix_write_begin(struct file *file, struct address_space *mapping,
428 loff_t pos, unsigned len,
429 struct page **pagep, void **fsdata)
430{
431 int ret;
432
433 ret = block_write_begin(mapping, pos, len, pagep, minix_get_block);
434 if (unlikely(ret))
435 minix_write_failed(mapping, pos + len);
436
437 return ret;
438}
439
440static sector_t minix_bmap(struct address_space *mapping, sector_t block)
441{
442 return generic_block_bmap(mapping,block,minix_get_block);
443}
444
445static const struct address_space_operations minix_aops = {
446 .dirty_folio = block_dirty_folio,
447 .invalidate_folio = block_invalidate_folio,
448 .read_folio = minix_read_folio,
449 .writepages = minix_writepages,
450 .write_begin = minix_write_begin,
451 .write_end = generic_write_end,
452 .migrate_folio = buffer_migrate_folio,
453 .bmap = minix_bmap,
454 .direct_IO = noop_direct_IO
455};
456
457static const struct inode_operations minix_symlink_inode_operations = {
458 .get_link = page_get_link,
459 .getattr = minix_getattr,
460};
461
462void minix_set_inode(struct inode *inode, dev_t rdev)
463{
464 if (S_ISREG(inode->i_mode)) {
465 inode->i_op = &minix_file_inode_operations;
466 inode->i_fop = &minix_file_operations;
467 inode->i_mapping->a_ops = &minix_aops;
468 } else if (S_ISDIR(inode->i_mode)) {
469 inode->i_op = &minix_dir_inode_operations;
470 inode->i_fop = &minix_dir_operations;
471 inode->i_mapping->a_ops = &minix_aops;
472 } else if (S_ISLNK(inode->i_mode)) {
473 inode->i_op = &minix_symlink_inode_operations;
474 inode_nohighmem(inode);
475 inode->i_mapping->a_ops = &minix_aops;
476 } else
477 init_special_inode(inode, inode->i_mode, rdev);
478}
479
480/*
481 * The minix V1 function to read an inode.
482 */
483static struct inode *V1_minix_iget(struct inode *inode)
484{
485 struct buffer_head * bh;
486 struct minix_inode * raw_inode;
487 struct minix_inode_info *minix_inode = minix_i(inode);
488 int i;
489
490 raw_inode = minix_V1_raw_inode(inode->i_sb, inode->i_ino, &bh);
491 if (!raw_inode) {
492 iget_failed(inode);
493 return ERR_PTR(-EIO);
494 }
495 if (raw_inode->i_nlinks == 0) {
496 printk("MINIX-fs: deleted inode referenced: %lu\n",
497 inode->i_ino);
498 brelse(bh);
499 iget_failed(inode);
500 return ERR_PTR(-ESTALE);
501 }
502 inode->i_mode = raw_inode->i_mode;
503 i_uid_write(inode, raw_inode->i_uid);
504 i_gid_write(inode, raw_inode->i_gid);
505 set_nlink(inode, raw_inode->i_nlinks);
506 inode->i_size = raw_inode->i_size;
507 inode_set_mtime_to_ts(inode,
508 inode_set_atime_to_ts(inode, inode_set_ctime(inode, raw_inode->i_time, 0)));
509 inode->i_blocks = 0;
510 for (i = 0; i < 9; i++)
511 minix_inode->u.i1_data[i] = raw_inode->i_zone[i];
512 minix_set_inode(inode, old_decode_dev(raw_inode->i_zone[0]));
513 brelse(bh);
514 unlock_new_inode(inode);
515 return inode;
516}
517
518/*
519 * The minix V2 function to read an inode.
520 */
521static struct inode *V2_minix_iget(struct inode *inode)
522{
523 struct buffer_head * bh;
524 struct minix2_inode * raw_inode;
525 struct minix_inode_info *minix_inode = minix_i(inode);
526 int i;
527
528 raw_inode = minix_V2_raw_inode(inode->i_sb, inode->i_ino, &bh);
529 if (!raw_inode) {
530 iget_failed(inode);
531 return ERR_PTR(-EIO);
532 }
533 if (raw_inode->i_nlinks == 0) {
534 printk("MINIX-fs: deleted inode referenced: %lu\n",
535 inode->i_ino);
536 brelse(bh);
537 iget_failed(inode);
538 return ERR_PTR(-ESTALE);
539 }
540 inode->i_mode = raw_inode->i_mode;
541 i_uid_write(inode, raw_inode->i_uid);
542 i_gid_write(inode, raw_inode->i_gid);
543 set_nlink(inode, raw_inode->i_nlinks);
544 inode->i_size = raw_inode->i_size;
545 inode_set_mtime(inode, raw_inode->i_mtime, 0);
546 inode_set_atime(inode, raw_inode->i_atime, 0);
547 inode_set_ctime(inode, raw_inode->i_ctime, 0);
548 inode->i_blocks = 0;
549 for (i = 0; i < 10; i++)
550 minix_inode->u.i2_data[i] = raw_inode->i_zone[i];
551 minix_set_inode(inode, old_decode_dev(raw_inode->i_zone[0]));
552 brelse(bh);
553 unlock_new_inode(inode);
554 return inode;
555}
556
557/*
558 * The global function to read an inode.
559 */
560struct inode *minix_iget(struct super_block *sb, unsigned long ino)
561{
562 struct inode *inode;
563
564 inode = iget_locked(sb, ino);
565 if (!inode)
566 return ERR_PTR(-ENOMEM);
567 if (!(inode->i_state & I_NEW))
568 return inode;
569
570 if (INODE_VERSION(inode) == MINIX_V1)
571 return V1_minix_iget(inode);
572 else
573 return V2_minix_iget(inode);
574}
575
576/*
577 * The minix V1 function to synchronize an inode.
578 */
579static struct buffer_head * V1_minix_update_inode(struct inode * inode)
580{
581 struct buffer_head * bh;
582 struct minix_inode * raw_inode;
583 struct minix_inode_info *minix_inode = minix_i(inode);
584 int i;
585
586 raw_inode = minix_V1_raw_inode(inode->i_sb, inode->i_ino, &bh);
587 if (!raw_inode)
588 return NULL;
589 raw_inode->i_mode = inode->i_mode;
590 raw_inode->i_uid = fs_high2lowuid(i_uid_read(inode));
591 raw_inode->i_gid = fs_high2lowgid(i_gid_read(inode));
592 raw_inode->i_nlinks = inode->i_nlink;
593 raw_inode->i_size = inode->i_size;
594 raw_inode->i_time = inode_get_mtime_sec(inode);
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 < 9; i++)
598 raw_inode->i_zone[i] = minix_inode->u.i1_data[i];
599 mark_buffer_dirty(bh);
600 return bh;
601}
602
603/*
604 * The minix V2 function to synchronize an inode.
605 */
606static struct buffer_head * V2_minix_update_inode(struct inode * inode)
607{
608 struct buffer_head * bh;
609 struct minix2_inode * raw_inode;
610 struct minix_inode_info *minix_inode = minix_i(inode);
611 int i;
612
613 raw_inode = minix_V2_raw_inode(inode->i_sb, inode->i_ino, &bh);
614 if (!raw_inode)
615 return NULL;
616 raw_inode->i_mode = inode->i_mode;
617 raw_inode->i_uid = fs_high2lowuid(i_uid_read(inode));
618 raw_inode->i_gid = fs_high2lowgid(i_gid_read(inode));
619 raw_inode->i_nlinks = inode->i_nlink;
620 raw_inode->i_size = inode->i_size;
621 raw_inode->i_mtime = inode_get_mtime_sec(inode);
622 raw_inode->i_atime = inode_get_atime_sec(inode);
623 raw_inode->i_ctime = inode_get_ctime_sec(inode);
624 if (S_ISCHR(inode->i_mode) || S_ISBLK(inode->i_mode))
625 raw_inode->i_zone[0] = old_encode_dev(inode->i_rdev);
626 else for (i = 0; i < 10; i++)
627 raw_inode->i_zone[i] = minix_inode->u.i2_data[i];
628 mark_buffer_dirty(bh);
629 return bh;
630}
631
632static int minix_write_inode(struct inode *inode, struct writeback_control *wbc)
633{
634 int err = 0;
635 struct buffer_head *bh;
636
637 if (INODE_VERSION(inode) == MINIX_V1)
638 bh = V1_minix_update_inode(inode);
639 else
640 bh = V2_minix_update_inode(inode);
641 if (!bh)
642 return -EIO;
643 if (wbc->sync_mode == WB_SYNC_ALL && buffer_dirty(bh)) {
644 sync_dirty_buffer(bh);
645 if (buffer_req(bh) && !buffer_uptodate(bh)) {
646 printk("IO error syncing minix inode [%s:%08lx]\n",
647 inode->i_sb->s_id, inode->i_ino);
648 err = -EIO;
649 }
650 }
651 brelse (bh);
652 return err;
653}
654
655int minix_getattr(struct mnt_idmap *idmap, const struct path *path,
656 struct kstat *stat, u32 request_mask, unsigned int flags)
657{
658 struct super_block *sb = path->dentry->d_sb;
659 struct inode *inode = d_inode(path->dentry);
660
661 generic_fillattr(&nop_mnt_idmap, request_mask, inode, stat);
662 if (INODE_VERSION(inode) == MINIX_V1)
663 stat->blocks = (BLOCK_SIZE / 512) * V1_minix_blocks(stat->size, sb);
664 else
665 stat->blocks = (sb->s_blocksize / 512) * V2_minix_blocks(stat->size, sb);
666 stat->blksize = sb->s_blocksize;
667 return 0;
668}
669
670/*
671 * The function that is called for file truncation.
672 */
673void minix_truncate(struct inode * inode)
674{
675 if (!(S_ISREG(inode->i_mode) || S_ISDIR(inode->i_mode) || S_ISLNK(inode->i_mode)))
676 return;
677 if (INODE_VERSION(inode) == MINIX_V1)
678 V1_minix_truncate(inode);
679 else
680 V2_minix_truncate(inode);
681}
682
683static struct dentry *minix_mount(struct file_system_type *fs_type,
684 int flags, const char *dev_name, void *data)
685{
686 return mount_bdev(fs_type, flags, dev_name, data, minix_fill_super);
687}
688
689static struct file_system_type minix_fs_type = {
690 .owner = THIS_MODULE,
691 .name = "minix",
692 .mount = minix_mount,
693 .kill_sb = kill_block_super,
694 .fs_flags = FS_REQUIRES_DEV,
695};
696MODULE_ALIAS_FS("minix");
697
698static int __init init_minix_fs(void)
699{
700 int err = init_inodecache();
701 if (err)
702 goto out1;
703 err = register_filesystem(&minix_fs_type);
704 if (err)
705 goto out;
706 return 0;
707out:
708 destroy_inodecache();
709out1:
710 return err;
711}
712
713static void __exit exit_minix_fs(void)
714{
715 unregister_filesystem(&minix_fs_type);
716 destroy_inodecache();
717}
718
719module_init(init_minix_fs)
720module_exit(exit_minix_fs)
721MODULE_LICENSE("GPL");
722
1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 * linux/fs/minix/inode.c
4 *
5 * Copyright (C) 1991, 1992 Linus Torvalds
6 *
7 * Copyright (C) 1996 Gertjan van Wingerde
8 * Minix V2 fs support.
9 *
10 * Modified for 680x0 by Andreas Schwab
11 * Updated to filesystem version 3 by Daniel Aragones
12 */
13
14#include <linux/module.h>
15#include "minix.h"
16#include <linux/buffer_head.h>
17#include <linux/slab.h>
18#include <linux/init.h>
19#include <linux/highuid.h>
20#include <linux/vfs.h>
21#include <linux/writeback.h>
22
23static int minix_write_inode(struct inode *inode,
24 struct writeback_control *wbc);
25static int minix_statfs(struct dentry *dentry, struct kstatfs *buf);
26static int minix_remount (struct super_block * sb, int * flags, char * data);
27
28static void minix_evict_inode(struct inode *inode)
29{
30 truncate_inode_pages_final(&inode->i_data);
31 if (!inode->i_nlink) {
32 inode->i_size = 0;
33 minix_truncate(inode);
34 }
35 invalidate_inode_buffers(inode);
36 clear_inode(inode);
37 if (!inode->i_nlink)
38 minix_free_inode(inode);
39}
40
41static void minix_put_super(struct super_block *sb)
42{
43 int i;
44 struct minix_sb_info *sbi = minix_sb(sb);
45
46 if (!sb_rdonly(sb)) {
47 if (sbi->s_version != MINIX_V3) /* s_state is now out from V3 sb */
48 sbi->s_ms->s_state = sbi->s_mount_state;
49 mark_buffer_dirty(sbi->s_sbh);
50 }
51 for (i = 0; i < sbi->s_imap_blocks; i++)
52 brelse(sbi->s_imap[i]);
53 for (i = 0; i < sbi->s_zmap_blocks; i++)
54 brelse(sbi->s_zmap[i]);
55 brelse (sbi->s_sbh);
56 kfree(sbi->s_imap);
57 sb->s_fs_info = NULL;
58 kfree(sbi);
59}
60
61static struct kmem_cache * minix_inode_cachep;
62
63static struct inode *minix_alloc_inode(struct super_block *sb)
64{
65 struct minix_inode_info *ei;
66 ei = alloc_inode_sb(sb, minix_inode_cachep, GFP_KERNEL);
67 if (!ei)
68 return NULL;
69 return &ei->vfs_inode;
70}
71
72static void minix_free_in_core_inode(struct inode *inode)
73{
74 kmem_cache_free(minix_inode_cachep, minix_i(inode));
75}
76
77static void init_once(void *foo)
78{
79 struct minix_inode_info *ei = (struct minix_inode_info *) foo;
80
81 inode_init_once(&ei->vfs_inode);
82}
83
84static int __init init_inodecache(void)
85{
86 minix_inode_cachep = kmem_cache_create("minix_inode_cache",
87 sizeof(struct minix_inode_info),
88 0, (SLAB_RECLAIM_ACCOUNT|
89 SLAB_MEM_SPREAD|SLAB_ACCOUNT),
90 init_once);
91 if (minix_inode_cachep == NULL)
92 return -ENOMEM;
93 return 0;
94}
95
96static void destroy_inodecache(void)
97{
98 /*
99 * Make sure all delayed rcu free inodes are flushed before we
100 * destroy cache.
101 */
102 rcu_barrier();
103 kmem_cache_destroy(minix_inode_cachep);
104}
105
106static const struct super_operations minix_sops = {
107 .alloc_inode = minix_alloc_inode,
108 .free_inode = minix_free_in_core_inode,
109 .write_inode = minix_write_inode,
110 .evict_inode = minix_evict_inode,
111 .put_super = minix_put_super,
112 .statfs = minix_statfs,
113 .remount_fs = minix_remount,
114};
115
116static int minix_remount (struct super_block * sb, int * flags, char * data)
117{
118 struct minix_sb_info * sbi = minix_sb(sb);
119 struct minix_super_block * ms;
120
121 sync_filesystem(sb);
122 ms = sbi->s_ms;
123 if ((bool)(*flags & SB_RDONLY) == sb_rdonly(sb))
124 return 0;
125 if (*flags & SB_RDONLY) {
126 if (ms->s_state & MINIX_VALID_FS ||
127 !(sbi->s_mount_state & MINIX_VALID_FS))
128 return 0;
129 /* Mounting a rw partition read-only. */
130 if (sbi->s_version != MINIX_V3)
131 ms->s_state = sbi->s_mount_state;
132 mark_buffer_dirty(sbi->s_sbh);
133 } else {
134 /* Mount a partition which is read-only, read-write. */
135 if (sbi->s_version != MINIX_V3) {
136 sbi->s_mount_state = ms->s_state;
137 ms->s_state &= ~MINIX_VALID_FS;
138 } else {
139 sbi->s_mount_state = MINIX_VALID_FS;
140 }
141 mark_buffer_dirty(sbi->s_sbh);
142
143 if (!(sbi->s_mount_state & MINIX_VALID_FS))
144 printk("MINIX-fs warning: remounting unchecked fs, "
145 "running fsck is recommended\n");
146 else if ((sbi->s_mount_state & MINIX_ERROR_FS))
147 printk("MINIX-fs warning: remounting fs with errors, "
148 "running fsck is recommended\n");
149 }
150 return 0;
151}
152
153static bool minix_check_superblock(struct super_block *sb)
154{
155 struct minix_sb_info *sbi = minix_sb(sb);
156
157 if (sbi->s_imap_blocks == 0 || sbi->s_zmap_blocks == 0)
158 return false;
159
160 /*
161 * s_max_size must not exceed the block mapping limitation. This check
162 * is only needed for V1 filesystems, since V2/V3 support an extra level
163 * of indirect blocks which places the limit well above U32_MAX.
164 */
165 if (sbi->s_version == MINIX_V1 &&
166 sb->s_maxbytes > (7 + 512 + 512*512) * BLOCK_SIZE)
167 return false;
168
169 return true;
170}
171
172static int minix_fill_super(struct super_block *s, void *data, int silent)
173{
174 struct buffer_head *bh;
175 struct buffer_head **map;
176 struct minix_super_block *ms;
177 struct minix3_super_block *m3s = NULL;
178 unsigned long i, block;
179 struct inode *root_inode;
180 struct minix_sb_info *sbi;
181 int ret = -EINVAL;
182
183 sbi = kzalloc(sizeof(struct minix_sb_info), GFP_KERNEL);
184 if (!sbi)
185 return -ENOMEM;
186 s->s_fs_info = sbi;
187
188 BUILD_BUG_ON(32 != sizeof (struct minix_inode));
189 BUILD_BUG_ON(64 != sizeof(struct minix2_inode));
190
191 if (!sb_set_blocksize(s, BLOCK_SIZE))
192 goto out_bad_hblock;
193
194 if (!(bh = sb_bread(s, 1)))
195 goto out_bad_sb;
196
197 ms = (struct minix_super_block *) bh->b_data;
198 sbi->s_ms = ms;
199 sbi->s_sbh = bh;
200 sbi->s_mount_state = ms->s_state;
201 sbi->s_ninodes = ms->s_ninodes;
202 sbi->s_nzones = ms->s_nzones;
203 sbi->s_imap_blocks = ms->s_imap_blocks;
204 sbi->s_zmap_blocks = ms->s_zmap_blocks;
205 sbi->s_firstdatazone = ms->s_firstdatazone;
206 sbi->s_log_zone_size = ms->s_log_zone_size;
207 s->s_maxbytes = ms->s_max_size;
208 s->s_magic = ms->s_magic;
209 if (s->s_magic == MINIX_SUPER_MAGIC) {
210 sbi->s_version = MINIX_V1;
211 sbi->s_dirsize = 16;
212 sbi->s_namelen = 14;
213 s->s_max_links = MINIX_LINK_MAX;
214 } else if (s->s_magic == MINIX_SUPER_MAGIC2) {
215 sbi->s_version = MINIX_V1;
216 sbi->s_dirsize = 32;
217 sbi->s_namelen = 30;
218 s->s_max_links = MINIX_LINK_MAX;
219 } else if (s->s_magic == MINIX2_SUPER_MAGIC) {
220 sbi->s_version = MINIX_V2;
221 sbi->s_nzones = ms->s_zones;
222 sbi->s_dirsize = 16;
223 sbi->s_namelen = 14;
224 s->s_max_links = MINIX2_LINK_MAX;
225 } else if (s->s_magic == MINIX2_SUPER_MAGIC2) {
226 sbi->s_version = MINIX_V2;
227 sbi->s_nzones = ms->s_zones;
228 sbi->s_dirsize = 32;
229 sbi->s_namelen = 30;
230 s->s_max_links = MINIX2_LINK_MAX;
231 } else if ( *(__u16 *)(bh->b_data + 24) == MINIX3_SUPER_MAGIC) {
232 m3s = (struct minix3_super_block *) bh->b_data;
233 s->s_magic = m3s->s_magic;
234 sbi->s_imap_blocks = m3s->s_imap_blocks;
235 sbi->s_zmap_blocks = m3s->s_zmap_blocks;
236 sbi->s_firstdatazone = m3s->s_firstdatazone;
237 sbi->s_log_zone_size = m3s->s_log_zone_size;
238 s->s_maxbytes = m3s->s_max_size;
239 sbi->s_ninodes = m3s->s_ninodes;
240 sbi->s_nzones = m3s->s_zones;
241 sbi->s_dirsize = 64;
242 sbi->s_namelen = 60;
243 sbi->s_version = MINIX_V3;
244 sbi->s_mount_state = MINIX_VALID_FS;
245 sb_set_blocksize(s, m3s->s_blocksize);
246 s->s_max_links = MINIX2_LINK_MAX;
247 } else
248 goto out_no_fs;
249
250 if (!minix_check_superblock(s))
251 goto out_illegal_sb;
252
253 /*
254 * Allocate the buffer map to keep the superblock small.
255 */
256 i = (sbi->s_imap_blocks + sbi->s_zmap_blocks) * sizeof(bh);
257 map = kzalloc(i, GFP_KERNEL);
258 if (!map)
259 goto out_no_map;
260 sbi->s_imap = &map[0];
261 sbi->s_zmap = &map[sbi->s_imap_blocks];
262
263 block=2;
264 for (i=0 ; i < sbi->s_imap_blocks ; i++) {
265 if (!(sbi->s_imap[i]=sb_bread(s, block)))
266 goto out_no_bitmap;
267 block++;
268 }
269 for (i=0 ; i < sbi->s_zmap_blocks ; i++) {
270 if (!(sbi->s_zmap[i]=sb_bread(s, block)))
271 goto out_no_bitmap;
272 block++;
273 }
274
275 minix_set_bit(0,sbi->s_imap[0]->b_data);
276 minix_set_bit(0,sbi->s_zmap[0]->b_data);
277
278 /* Apparently minix can create filesystems that allocate more blocks for
279 * the bitmaps than needed. We simply ignore that, but verify it didn't
280 * create one with not enough blocks and bail out if so.
281 */
282 block = minix_blocks_needed(sbi->s_ninodes, s->s_blocksize);
283 if (sbi->s_imap_blocks < block) {
284 printk("MINIX-fs: file system does not have enough "
285 "imap blocks allocated. Refusing to mount.\n");
286 goto out_no_bitmap;
287 }
288
289 block = minix_blocks_needed(
290 (sbi->s_nzones - sbi->s_firstdatazone + 1),
291 s->s_blocksize);
292 if (sbi->s_zmap_blocks < block) {
293 printk("MINIX-fs: file system does not have enough "
294 "zmap blocks allocated. Refusing to mount.\n");
295 goto out_no_bitmap;
296 }
297
298 /* set up enough so that it can read an inode */
299 s->s_op = &minix_sops;
300 s->s_time_min = 0;
301 s->s_time_max = U32_MAX;
302 root_inode = minix_iget(s, MINIX_ROOT_INO);
303 if (IS_ERR(root_inode)) {
304 ret = PTR_ERR(root_inode);
305 goto out_no_root;
306 }
307
308 ret = -ENOMEM;
309 s->s_root = d_make_root(root_inode);
310 if (!s->s_root)
311 goto out_no_root;
312
313 if (!sb_rdonly(s)) {
314 if (sbi->s_version != MINIX_V3) /* s_state is now out from V3 sb */
315 ms->s_state &= ~MINIX_VALID_FS;
316 mark_buffer_dirty(bh);
317 }
318 if (!(sbi->s_mount_state & MINIX_VALID_FS))
319 printk("MINIX-fs: mounting unchecked file system, "
320 "running fsck is recommended\n");
321 else if (sbi->s_mount_state & MINIX_ERROR_FS)
322 printk("MINIX-fs: mounting file system with errors, "
323 "running fsck is recommended\n");
324
325 return 0;
326
327out_no_root:
328 if (!silent)
329 printk("MINIX-fs: get root inode failed\n");
330 goto out_freemap;
331
332out_no_bitmap:
333 printk("MINIX-fs: bad superblock or unable to read bitmaps\n");
334out_freemap:
335 for (i = 0; i < sbi->s_imap_blocks; i++)
336 brelse(sbi->s_imap[i]);
337 for (i = 0; i < sbi->s_zmap_blocks; i++)
338 brelse(sbi->s_zmap[i]);
339 kfree(sbi->s_imap);
340 goto out_release;
341
342out_no_map:
343 ret = -ENOMEM;
344 if (!silent)
345 printk("MINIX-fs: can't allocate map\n");
346 goto out_release;
347
348out_illegal_sb:
349 if (!silent)
350 printk("MINIX-fs: bad superblock\n");
351 goto out_release;
352
353out_no_fs:
354 if (!silent)
355 printk("VFS: Can't find a Minix filesystem V1 | V2 | V3 "
356 "on device %s.\n", s->s_id);
357out_release:
358 brelse(bh);
359 goto out;
360
361out_bad_hblock:
362 printk("MINIX-fs: blocksize too small for device\n");
363 goto out;
364
365out_bad_sb:
366 printk("MINIX-fs: unable to read superblock\n");
367out:
368 s->s_fs_info = NULL;
369 kfree(sbi);
370 return ret;
371}
372
373static int minix_statfs(struct dentry *dentry, struct kstatfs *buf)
374{
375 struct super_block *sb = dentry->d_sb;
376 struct minix_sb_info *sbi = minix_sb(sb);
377 u64 id = huge_encode_dev(sb->s_bdev->bd_dev);
378 buf->f_type = sb->s_magic;
379 buf->f_bsize = sb->s_blocksize;
380 buf->f_blocks = (sbi->s_nzones - sbi->s_firstdatazone) << sbi->s_log_zone_size;
381 buf->f_bfree = minix_count_free_blocks(sb);
382 buf->f_bavail = buf->f_bfree;
383 buf->f_files = sbi->s_ninodes;
384 buf->f_ffree = minix_count_free_inodes(sb);
385 buf->f_namelen = sbi->s_namelen;
386 buf->f_fsid = u64_to_fsid(id);
387
388 return 0;
389}
390
391static int minix_get_block(struct inode *inode, sector_t block,
392 struct buffer_head *bh_result, int create)
393{
394 if (INODE_VERSION(inode) == MINIX_V1)
395 return V1_minix_get_block(inode, block, bh_result, create);
396 else
397 return V2_minix_get_block(inode, block, bh_result, create);
398}
399
400static int minix_writepage(struct page *page, struct writeback_control *wbc)
401{
402 return block_write_full_page(page, minix_get_block, wbc);
403}
404
405static int minix_read_folio(struct file *file, struct folio *folio)
406{
407 return block_read_full_folio(folio, minix_get_block);
408}
409
410int minix_prepare_chunk(struct page *page, loff_t pos, unsigned len)
411{
412 return __block_write_begin(page, pos, len, minix_get_block);
413}
414
415static void minix_write_failed(struct address_space *mapping, loff_t to)
416{
417 struct inode *inode = mapping->host;
418
419 if (to > inode->i_size) {
420 truncate_pagecache(inode, inode->i_size);
421 minix_truncate(inode);
422 }
423}
424
425static int minix_write_begin(struct file *file, struct address_space *mapping,
426 loff_t pos, unsigned len,
427 struct page **pagep, void **fsdata)
428{
429 int ret;
430
431 ret = block_write_begin(mapping, pos, len, pagep, minix_get_block);
432 if (unlikely(ret))
433 minix_write_failed(mapping, pos + len);
434
435 return ret;
436}
437
438static sector_t minix_bmap(struct address_space *mapping, sector_t block)
439{
440 return generic_block_bmap(mapping,block,minix_get_block);
441}
442
443static const struct address_space_operations minix_aops = {
444 .dirty_folio = block_dirty_folio,
445 .invalidate_folio = block_invalidate_folio,
446 .read_folio = minix_read_folio,
447 .writepage = minix_writepage,
448 .write_begin = minix_write_begin,
449 .write_end = generic_write_end,
450 .bmap = minix_bmap,
451 .direct_IO = noop_direct_IO
452};
453
454static const struct inode_operations minix_symlink_inode_operations = {
455 .get_link = page_get_link,
456 .getattr = minix_getattr,
457};
458
459void minix_set_inode(struct inode *inode, dev_t rdev)
460{
461 if (S_ISREG(inode->i_mode)) {
462 inode->i_op = &minix_file_inode_operations;
463 inode->i_fop = &minix_file_operations;
464 inode->i_mapping->a_ops = &minix_aops;
465 } else if (S_ISDIR(inode->i_mode)) {
466 inode->i_op = &minix_dir_inode_operations;
467 inode->i_fop = &minix_dir_operations;
468 inode->i_mapping->a_ops = &minix_aops;
469 } else if (S_ISLNK(inode->i_mode)) {
470 inode->i_op = &minix_symlink_inode_operations;
471 inode_nohighmem(inode);
472 inode->i_mapping->a_ops = &minix_aops;
473 } else
474 init_special_inode(inode, inode->i_mode, rdev);
475}
476
477/*
478 * The minix V1 function to read an inode.
479 */
480static struct inode *V1_minix_iget(struct inode *inode)
481{
482 struct buffer_head * bh;
483 struct minix_inode * raw_inode;
484 struct minix_inode_info *minix_inode = minix_i(inode);
485 int i;
486
487 raw_inode = minix_V1_raw_inode(inode->i_sb, inode->i_ino, &bh);
488 if (!raw_inode) {
489 iget_failed(inode);
490 return ERR_PTR(-EIO);
491 }
492 if (raw_inode->i_nlinks == 0) {
493 printk("MINIX-fs: deleted inode referenced: %lu\n",
494 inode->i_ino);
495 brelse(bh);
496 iget_failed(inode);
497 return ERR_PTR(-ESTALE);
498 }
499 inode->i_mode = raw_inode->i_mode;
500 i_uid_write(inode, raw_inode->i_uid);
501 i_gid_write(inode, raw_inode->i_gid);
502 set_nlink(inode, raw_inode->i_nlinks);
503 inode->i_size = raw_inode->i_size;
504 inode->i_mtime.tv_sec = inode->i_atime.tv_sec = inode->i_ctime.tv_sec = raw_inode->i_time;
505 inode->i_mtime.tv_nsec = 0;
506 inode->i_atime.tv_nsec = 0;
507 inode->i_ctime.tv_nsec = 0;
508 inode->i_blocks = 0;
509 for (i = 0; i < 9; i++)
510 minix_inode->u.i1_data[i] = raw_inode->i_zone[i];
511 minix_set_inode(inode, old_decode_dev(raw_inode->i_zone[0]));
512 brelse(bh);
513 unlock_new_inode(inode);
514 return inode;
515}
516
517/*
518 * The minix V2 function to read an inode.
519 */
520static struct inode *V2_minix_iget(struct inode *inode)
521{
522 struct buffer_head * bh;
523 struct minix2_inode * raw_inode;
524 struct minix_inode_info *minix_inode = minix_i(inode);
525 int i;
526
527 raw_inode = minix_V2_raw_inode(inode->i_sb, inode->i_ino, &bh);
528 if (!raw_inode) {
529 iget_failed(inode);
530 return ERR_PTR(-EIO);
531 }
532 if (raw_inode->i_nlinks == 0) {
533 printk("MINIX-fs: deleted inode referenced: %lu\n",
534 inode->i_ino);
535 brelse(bh);
536 iget_failed(inode);
537 return ERR_PTR(-ESTALE);
538 }
539 inode->i_mode = raw_inode->i_mode;
540 i_uid_write(inode, raw_inode->i_uid);
541 i_gid_write(inode, raw_inode->i_gid);
542 set_nlink(inode, raw_inode->i_nlinks);
543 inode->i_size = raw_inode->i_size;
544 inode->i_mtime.tv_sec = raw_inode->i_mtime;
545 inode->i_atime.tv_sec = raw_inode->i_atime;
546 inode->i_ctime.tv_sec = raw_inode->i_ctime;
547 inode->i_mtime.tv_nsec = 0;
548 inode->i_atime.tv_nsec = 0;
549 inode->i_ctime.tv_nsec = 0;
550 inode->i_blocks = 0;
551 for (i = 0; i < 10; i++)
552 minix_inode->u.i2_data[i] = raw_inode->i_zone[i];
553 minix_set_inode(inode, old_decode_dev(raw_inode->i_zone[0]));
554 brelse(bh);
555 unlock_new_inode(inode);
556 return inode;
557}
558
559/*
560 * The global function to read an inode.
561 */
562struct inode *minix_iget(struct super_block *sb, unsigned long ino)
563{
564 struct inode *inode;
565
566 inode = iget_locked(sb, ino);
567 if (!inode)
568 return ERR_PTR(-ENOMEM);
569 if (!(inode->i_state & I_NEW))
570 return inode;
571
572 if (INODE_VERSION(inode) == MINIX_V1)
573 return V1_minix_iget(inode);
574 else
575 return V2_minix_iget(inode);
576}
577
578/*
579 * The minix V1 function to synchronize an inode.
580 */
581static struct buffer_head * V1_minix_update_inode(struct inode * inode)
582{
583 struct buffer_head * bh;
584 struct minix_inode * raw_inode;
585 struct minix_inode_info *minix_inode = minix_i(inode);
586 int i;
587
588 raw_inode = minix_V1_raw_inode(inode->i_sb, inode->i_ino, &bh);
589 if (!raw_inode)
590 return NULL;
591 raw_inode->i_mode = inode->i_mode;
592 raw_inode->i_uid = fs_high2lowuid(i_uid_read(inode));
593 raw_inode->i_gid = fs_high2lowgid(i_gid_read(inode));
594 raw_inode->i_nlinks = inode->i_nlink;
595 raw_inode->i_size = inode->i_size;
596 raw_inode->i_time = inode->i_mtime.tv_sec;
597 if (S_ISCHR(inode->i_mode) || S_ISBLK(inode->i_mode))
598 raw_inode->i_zone[0] = old_encode_dev(inode->i_rdev);
599 else for (i = 0; i < 9; i++)
600 raw_inode->i_zone[i] = minix_inode->u.i1_data[i];
601 mark_buffer_dirty(bh);
602 return bh;
603}
604
605/*
606 * The minix V2 function to synchronize an inode.
607 */
608static struct buffer_head * V2_minix_update_inode(struct inode * inode)
609{
610 struct buffer_head * bh;
611 struct minix2_inode * raw_inode;
612 struct minix_inode_info *minix_inode = minix_i(inode);
613 int i;
614
615 raw_inode = minix_V2_raw_inode(inode->i_sb, inode->i_ino, &bh);
616 if (!raw_inode)
617 return NULL;
618 raw_inode->i_mode = inode->i_mode;
619 raw_inode->i_uid = fs_high2lowuid(i_uid_read(inode));
620 raw_inode->i_gid = fs_high2lowgid(i_gid_read(inode));
621 raw_inode->i_nlinks = inode->i_nlink;
622 raw_inode->i_size = inode->i_size;
623 raw_inode->i_mtime = inode->i_mtime.tv_sec;
624 raw_inode->i_atime = inode->i_atime.tv_sec;
625 raw_inode->i_ctime = inode->i_ctime.tv_sec;
626 if (S_ISCHR(inode->i_mode) || S_ISBLK(inode->i_mode))
627 raw_inode->i_zone[0] = old_encode_dev(inode->i_rdev);
628 else for (i = 0; i < 10; i++)
629 raw_inode->i_zone[i] = minix_inode->u.i2_data[i];
630 mark_buffer_dirty(bh);
631 return bh;
632}
633
634static int minix_write_inode(struct inode *inode, struct writeback_control *wbc)
635{
636 int err = 0;
637 struct buffer_head *bh;
638
639 if (INODE_VERSION(inode) == MINIX_V1)
640 bh = V1_minix_update_inode(inode);
641 else
642 bh = V2_minix_update_inode(inode);
643 if (!bh)
644 return -EIO;
645 if (wbc->sync_mode == WB_SYNC_ALL && buffer_dirty(bh)) {
646 sync_dirty_buffer(bh);
647 if (buffer_req(bh) && !buffer_uptodate(bh)) {
648 printk("IO error syncing minix inode [%s:%08lx]\n",
649 inode->i_sb->s_id, inode->i_ino);
650 err = -EIO;
651 }
652 }
653 brelse (bh);
654 return err;
655}
656
657int minix_getattr(struct user_namespace *mnt_userns, const struct path *path,
658 struct kstat *stat, u32 request_mask, unsigned int flags)
659{
660 struct super_block *sb = path->dentry->d_sb;
661 struct inode *inode = d_inode(path->dentry);
662
663 generic_fillattr(&init_user_ns, inode, stat);
664 if (INODE_VERSION(inode) == MINIX_V1)
665 stat->blocks = (BLOCK_SIZE / 512) * V1_minix_blocks(stat->size, sb);
666 else
667 stat->blocks = (sb->s_blocksize / 512) * V2_minix_blocks(stat->size, sb);
668 stat->blksize = sb->s_blocksize;
669 return 0;
670}
671
672/*
673 * The function that is called for file truncation.
674 */
675void minix_truncate(struct inode * inode)
676{
677 if (!(S_ISREG(inode->i_mode) || S_ISDIR(inode->i_mode) || S_ISLNK(inode->i_mode)))
678 return;
679 if (INODE_VERSION(inode) == MINIX_V1)
680 V1_minix_truncate(inode);
681 else
682 V2_minix_truncate(inode);
683}
684
685static struct dentry *minix_mount(struct file_system_type *fs_type,
686 int flags, const char *dev_name, void *data)
687{
688 return mount_bdev(fs_type, flags, dev_name, data, minix_fill_super);
689}
690
691static struct file_system_type minix_fs_type = {
692 .owner = THIS_MODULE,
693 .name = "minix",
694 .mount = minix_mount,
695 .kill_sb = kill_block_super,
696 .fs_flags = FS_REQUIRES_DEV,
697};
698MODULE_ALIAS_FS("minix");
699
700static int __init init_minix_fs(void)
701{
702 int err = init_inodecache();
703 if (err)
704 goto out1;
705 err = register_filesystem(&minix_fs_type);
706 if (err)
707 goto out;
708 return 0;
709out:
710 destroy_inodecache();
711out1:
712 return err;
713}
714
715static void __exit exit_minix_fs(void)
716{
717 unregister_filesystem(&minix_fs_type);
718 destroy_inodecache();
719}
720
721module_init(init_minix_fs)
722module_exit(exit_minix_fs)
723MODULE_LICENSE("GPL");
724