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
25 static int minix_write_inode(struct inode *inode,
26 struct writeback_control *wbc);
27 static int minix_statfs(struct dentry *dentry, struct kstatfs *buf);
28
minix_evict_inode(struct inode * inode)29 static 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
minix_put_super(struct super_block * sb)42 static 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
62 static struct kmem_cache * minix_inode_cachep;
63
minix_alloc_inode(struct super_block * sb)64 static 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
minix_free_in_core_inode(struct inode * inode)73 static void minix_free_in_core_inode(struct inode *inode)
74 {
75 kmem_cache_free(minix_inode_cachep, minix_i(inode));
76 }
77
init_once(void * foo)78 static 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
init_inodecache(void)85 static 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
destroy_inodecache(void)97 static 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
107 static 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
minix_reconfigure(struct fs_context * fc)116 static 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
minix_check_superblock(struct super_block * sb)154 static 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
minix_fill_super(struct super_block * s,struct fs_context * fc)173 static 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
329 out_no_root:
330 if (!silent)
331 printk("MINIX-fs: get root inode failed\n");
332 goto out_freemap;
333
334 out_no_bitmap:
335 printk("MINIX-fs: bad superblock or unable to read bitmaps\n");
336 out_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
344 out_no_map:
345 ret = -ENOMEM;
346 if (!silent)
347 printk("MINIX-fs: can't allocate map\n");
348 goto out_release;
349
350 out_illegal_sb:
351 if (!silent)
352 printk("MINIX-fs: bad superblock\n");
353 goto out_release;
354
355 out_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);
359 out_release:
360 brelse(bh);
361 goto out;
362
363 out_bad_hblock:
364 printk("MINIX-fs: blocksize too small for device\n");
365 goto out;
366
367 out_bad_sb:
368 printk("MINIX-fs: unable to read superblock\n");
369 out:
370 s->s_fs_info = NULL;
371 kfree(sbi);
372 return ret;
373 }
374
minix_get_tree(struct fs_context * fc)375 static int minix_get_tree(struct fs_context *fc)
376 {
377 return get_tree_bdev(fc, minix_fill_super);
378 }
379
380 static const struct fs_context_operations minix_context_ops = {
381 .get_tree = minix_get_tree,
382 .reconfigure = minix_reconfigure,
383 };
384
minix_init_fs_context(struct fs_context * fc)385 static int minix_init_fs_context(struct fs_context *fc)
386 {
387 fc->ops = &minix_context_ops;
388
389 return 0;
390 }
391
minix_statfs(struct dentry * dentry,struct kstatfs * buf)392 static 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
minix_get_block(struct inode * inode,sector_t block,struct buffer_head * bh_result,int create)410 static 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
minix_writepages(struct address_space * mapping,struct writeback_control * wbc)419 static int minix_writepages(struct address_space *mapping,
420 struct writeback_control *wbc)
421 {
422 return mpage_writepages(mapping, wbc, minix_get_block);
423 }
424
minix_read_folio(struct file * file,struct folio * folio)425 static int minix_read_folio(struct file *file, struct folio *folio)
426 {
427 return block_read_full_folio(folio, minix_get_block);
428 }
429
minix_prepare_chunk(struct folio * folio,loff_t pos,unsigned len)430 int 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
minix_write_failed(struct address_space * mapping,loff_t to)435 static 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
minix_write_begin(struct file * file,struct address_space * mapping,loff_t pos,unsigned len,struct folio ** foliop,void ** fsdata)445 static 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
minix_bmap(struct address_space * mapping,sector_t block)458 static sector_t minix_bmap(struct address_space *mapping, sector_t block)
459 {
460 return generic_block_bmap(mapping,block,minix_get_block);
461 }
462
463 static 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
475 static const struct inode_operations minix_symlink_inode_operations = {
476 .get_link = page_get_link,
477 .getattr = minix_getattr,
478 };
479
minix_set_inode(struct inode * inode,dev_t rdev)480 void 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 */
V1_minix_iget(struct inode * inode)501 static 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 */
V2_minix_iget(struct inode * inode)539 static 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 */
minix_iget(struct super_block * sb,unsigned long ino)578 struct 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 */
V1_minix_update_inode(struct inode * inode)597 static 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 */
V2_minix_update_inode(struct inode * inode)624 static 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
minix_write_inode(struct inode * inode,struct writeback_control * wbc)650 static 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
minix_getattr(struct mnt_idmap * idmap,const struct path * path,struct kstat * stat,u32 request_mask,unsigned int flags)673 int 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 */
minix_truncate(struct inode * inode)691 void 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
701 static 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 };
708 MODULE_ALIAS_FS("minix");
709
init_minix_fs(void)710 static 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;
719 out:
720 destroy_inodecache();
721 out1:
722 return err;
723 }
724
exit_minix_fs(void)725 static void __exit exit_minix_fs(void)
726 {
727 unregister_filesystem(&minix_fs_type);
728 destroy_inodecache();
729 }
730
731 module_init(init_minix_fs)
732 module_exit(exit_minix_fs)
733 MODULE_DESCRIPTION("Minix file system");
734 MODULE_LICENSE("GPL");
735
736