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_sync_inode_metadata(struct inode *inode,
28 struct writeback_control *wbc);
29 static int minix_statfs(struct dentry *dentry, struct kstatfs *buf);
30
__minix_error_inode(struct inode * inode,const char * function,unsigned int line,const char * fmt,...)31 void __minix_error_inode(struct inode *inode, const char *function,
32 unsigned int line, const char *fmt, ...)
33 {
34 struct va_format vaf;
35 va_list args;
36
37 va_start(args, fmt);
38 vaf.fmt = fmt;
39 vaf.va = &args;
40 printk(KERN_CRIT "minix-fs error (device %s): %s:%d: "
41 "inode #%llu: comm %s: %pV\n",
42 inode->i_sb->s_id, function, line, inode->i_ino,
43 current->comm, &vaf);
44 va_end(args);
45 }
46
minix_evict_inode(struct inode * inode)47 static void minix_evict_inode(struct inode *inode)
48 {
49 truncate_inode_pages_final(&inode->i_data);
50 if (!inode->i_nlink) {
51 inode->i_size = 0;
52 minix_truncate(inode);
53 } else {
54 mmb_sync(&minix_i(inode)->i_metadata_bhs);
55 }
56 mmb_invalidate(&minix_i(inode)->i_metadata_bhs);
57 clear_inode(inode);
58 if (!inode->i_nlink)
59 minix_free_inode(inode);
60 }
61
minix_put_super(struct super_block * sb)62 static void minix_put_super(struct super_block *sb)
63 {
64 int i;
65 struct minix_sb_info *sbi = minix_sb(sb);
66
67 if (!sb_rdonly(sb)) {
68 if (sbi->s_version != MINIX_V3) /* s_state is now out from V3 sb */
69 sbi->s_ms->s_state = sbi->s_mount_state;
70 mark_buffer_dirty(sbi->s_sbh);
71 }
72 for (i = 0; i < sbi->s_imap_blocks; i++)
73 brelse(sbi->s_imap[i]);
74 for (i = 0; i < sbi->s_zmap_blocks; i++)
75 brelse(sbi->s_zmap[i]);
76 brelse (sbi->s_sbh);
77 kfree(sbi->s_imap);
78 sb->s_fs_info = NULL;
79 kfree(sbi);
80 }
81
82 static struct kmem_cache * minix_inode_cachep;
83
minix_alloc_inode(struct super_block * sb)84 static struct inode *minix_alloc_inode(struct super_block *sb)
85 {
86 struct minix_inode_info *ei;
87 ei = alloc_inode_sb(sb, minix_inode_cachep, GFP_KERNEL);
88 if (!ei)
89 return NULL;
90 mmb_init(&ei->i_metadata_bhs, &ei->vfs_inode.i_data);
91
92 return &ei->vfs_inode;
93 }
94
minix_free_in_core_inode(struct inode * inode)95 static void minix_free_in_core_inode(struct inode *inode)
96 {
97 kmem_cache_free(minix_inode_cachep, minix_i(inode));
98 }
99
init_once(void * foo)100 static void init_once(void *foo)
101 {
102 struct minix_inode_info *ei = (struct minix_inode_info *) foo;
103
104 inode_init_once(&ei->vfs_inode);
105 }
106
init_inodecache(void)107 static int __init init_inodecache(void)
108 {
109 minix_inode_cachep = kmem_cache_create("minix_inode_cache",
110 sizeof(struct minix_inode_info),
111 0, (SLAB_RECLAIM_ACCOUNT|
112 SLAB_ACCOUNT),
113 init_once);
114 if (minix_inode_cachep == NULL)
115 return -ENOMEM;
116 return 0;
117 }
118
destroy_inodecache(void)119 static void destroy_inodecache(void)
120 {
121 /*
122 * Make sure all delayed rcu free inodes are flushed before we
123 * destroy cache.
124 */
125 rcu_barrier();
126 kmem_cache_destroy(minix_inode_cachep);
127 }
128
129 static const struct super_operations minix_sops = {
130 .alloc_inode = minix_alloc_inode,
131 .free_inode = minix_free_in_core_inode,
132 .write_inode = minix_write_inode,
133 .sync_inode_metadata = minix_sync_inode_metadata,
134 .evict_inode = minix_evict_inode,
135 .put_super = minix_put_super,
136 .statfs = minix_statfs,
137 };
138
minix_reconfigure(struct fs_context * fc)139 static int minix_reconfigure(struct fs_context *fc)
140 {
141 struct minix_super_block * ms;
142 struct super_block *sb = fc->root->d_sb;
143 struct minix_sb_info * sbi = sb->s_fs_info;
144
145 sync_filesystem(sb);
146 ms = sbi->s_ms;
147 if ((bool)(fc->sb_flags & SB_RDONLY) == sb_rdonly(sb))
148 return 0;
149 if (fc->sb_flags & SB_RDONLY) {
150 if (ms->s_state & MINIX_VALID_FS ||
151 !(sbi->s_mount_state & MINIX_VALID_FS))
152 return 0;
153 /* Mounting a rw partition read-only. */
154 if (sbi->s_version != MINIX_V3)
155 ms->s_state = sbi->s_mount_state;
156 mark_buffer_dirty(sbi->s_sbh);
157 } else {
158 /* Mount a partition which is read-only, read-write. */
159 if (sbi->s_version != MINIX_V3) {
160 sbi->s_mount_state = ms->s_state;
161 ms->s_state &= ~MINIX_VALID_FS;
162 } else {
163 sbi->s_mount_state = MINIX_VALID_FS;
164 }
165 mark_buffer_dirty(sbi->s_sbh);
166
167 if (!(sbi->s_mount_state & MINIX_VALID_FS))
168 printk("MINIX-fs warning: remounting unchecked fs, "
169 "running fsck is recommended\n");
170 else if ((sbi->s_mount_state & MINIX_ERROR_FS))
171 printk("MINIX-fs warning: remounting fs with errors, "
172 "running fsck is recommended\n");
173 }
174 return 0;
175 }
176
minix_check_superblock(struct super_block * sb)177 static bool minix_check_superblock(struct super_block *sb)
178 {
179 struct minix_sb_info *sbi = minix_sb(sb);
180 unsigned long block;
181
182 if (sbi->s_log_zone_size != 0) {
183 printk("minix-fs error: zone size must equal block size. "
184 "s_log_zone_size > 0 is not supported.\n");
185 return false;
186 }
187
188 if (sbi->s_ninodes < 1 || sbi->s_firstdatazone <= 4 ||
189 sbi->s_firstdatazone >= sbi->s_nzones)
190 return false;
191
192 /* Apparently minix can create filesystems that allocate more blocks for
193 * the bitmaps than needed. We simply ignore that, but verify it didn't
194 * create one with not enough blocks and bail out if so.
195 */
196 block = minix_blocks_needed(sbi->s_ninodes, sb->s_blocksize);
197 if (sbi->s_imap_blocks < block) {
198 printk("MINIX-fs: file system does not have enough "
199 "imap blocks allocated. Refusing to mount.\n");
200 return false;
201 }
202
203 block = minix_blocks_needed(
204 (sbi->s_nzones - sbi->s_firstdatazone + 1),
205 sb->s_blocksize);
206 if (sbi->s_zmap_blocks < block) {
207 printk("MINIX-fs: file system does not have enough "
208 "zmap blocks allocated. Refusing to mount.\n");
209 return false;
210 }
211
212 /*
213 * s_max_size must not exceed the block mapping limitation. This check
214 * is only needed for V1 filesystems, since V2/V3 support an extra level
215 * of indirect blocks which places the limit well above U32_MAX.
216 */
217 if (sbi->s_version == MINIX_V1 &&
218 sb->s_maxbytes > (7 + 512 + 512*512) * BLOCK_SIZE)
219 return false;
220
221 return true;
222 }
223
minix_fill_super(struct super_block * s,struct fs_context * fc)224 static int minix_fill_super(struct super_block *s, struct fs_context *fc)
225 {
226 struct buffer_head *bh;
227 struct buffer_head **map;
228 struct minix_super_block *ms;
229 struct minix3_super_block *m3s = NULL;
230 unsigned long i, block;
231 struct inode *root_inode;
232 struct minix_sb_info *sbi;
233 int ret = -EINVAL;
234 int silent = fc->sb_flags & SB_SILENT;
235
236 sbi = kzalloc_obj(struct minix_sb_info);
237 if (!sbi)
238 return -ENOMEM;
239 s->s_fs_info = sbi;
240
241 BUILD_BUG_ON(32 != sizeof (struct minix_inode));
242 BUILD_BUG_ON(64 != sizeof(struct minix2_inode));
243
244 if (!sb_set_blocksize(s, BLOCK_SIZE))
245 goto out_bad_hblock;
246
247 if (!(bh = sb_bread(s, 1)))
248 goto out_bad_sb;
249
250 ms = (struct minix_super_block *) bh->b_data;
251 sbi->s_ms = ms;
252 sbi->s_sbh = bh;
253 sbi->s_mount_state = ms->s_state;
254 sbi->s_ninodes = ms->s_ninodes;
255 sbi->s_nzones = ms->s_nzones;
256 sbi->s_imap_blocks = ms->s_imap_blocks;
257 sbi->s_zmap_blocks = ms->s_zmap_blocks;
258 sbi->s_firstdatazone = ms->s_firstdatazone;
259 sbi->s_log_zone_size = ms->s_log_zone_size;
260 s->s_maxbytes = ms->s_max_size;
261 s->s_magic = ms->s_magic;
262 if (s->s_magic == MINIX_SUPER_MAGIC) {
263 sbi->s_version = MINIX_V1;
264 sbi->s_dirsize = 16;
265 sbi->s_namelen = 14;
266 s->s_max_links = MINIX_LINK_MAX;
267 } else if (s->s_magic == MINIX_SUPER_MAGIC2) {
268 sbi->s_version = MINIX_V1;
269 sbi->s_dirsize = 32;
270 sbi->s_namelen = 30;
271 s->s_max_links = MINIX_LINK_MAX;
272 } else if (s->s_magic == MINIX2_SUPER_MAGIC) {
273 sbi->s_version = MINIX_V2;
274 sbi->s_nzones = ms->s_zones;
275 sbi->s_dirsize = 16;
276 sbi->s_namelen = 14;
277 s->s_max_links = MINIX2_LINK_MAX;
278 } else if (s->s_magic == MINIX2_SUPER_MAGIC2) {
279 sbi->s_version = MINIX_V2;
280 sbi->s_nzones = ms->s_zones;
281 sbi->s_dirsize = 32;
282 sbi->s_namelen = 30;
283 s->s_max_links = MINIX2_LINK_MAX;
284 } else if ( *(__u16 *)(bh->b_data + 24) == MINIX3_SUPER_MAGIC) {
285 m3s = (struct minix3_super_block *) bh->b_data;
286 s->s_magic = m3s->s_magic;
287 sbi->s_imap_blocks = m3s->s_imap_blocks;
288 sbi->s_zmap_blocks = m3s->s_zmap_blocks;
289 sbi->s_firstdatazone = m3s->s_firstdatazone;
290 sbi->s_log_zone_size = m3s->s_log_zone_size;
291 s->s_maxbytes = m3s->s_max_size;
292 sbi->s_ninodes = m3s->s_ninodes;
293 sbi->s_nzones = m3s->s_zones;
294 sbi->s_dirsize = 64;
295 sbi->s_namelen = 60;
296 sbi->s_version = MINIX_V3;
297 sbi->s_mount_state = MINIX_VALID_FS;
298 if (!sb_set_blocksize(s, m3s->s_blocksize))
299 goto out_release;
300 s->s_max_links = MINIX2_LINK_MAX;
301 } else
302 goto out_no_fs;
303
304 if (!minix_check_superblock(s))
305 goto out_illegal_sb;
306
307 /*
308 * Allocate the buffer map to keep the superblock small.
309 */
310 i = (sbi->s_imap_blocks + sbi->s_zmap_blocks) * sizeof(bh);
311 map = kzalloc(i, GFP_KERNEL);
312 if (!map)
313 goto out_no_map;
314 sbi->s_imap = &map[0];
315 sbi->s_zmap = &map[sbi->s_imap_blocks];
316
317 block=2;
318 for (i=0 ; i < sbi->s_imap_blocks ; i++) {
319 if (!(sbi->s_imap[i]=sb_bread(s, block)))
320 goto out_no_bitmap;
321 block++;
322 }
323 for (i=0 ; i < sbi->s_zmap_blocks ; i++) {
324 if (!(sbi->s_zmap[i]=sb_bread(s, block)))
325 goto out_no_bitmap;
326 block++;
327 }
328
329 minix_set_bit(0,sbi->s_imap[0]->b_data);
330 minix_set_bit(0,sbi->s_zmap[0]->b_data);
331
332 /* set up enough so that it can read an inode */
333 s->s_op = &minix_sops;
334 s->s_time_min = 0;
335 s->s_time_max = U32_MAX;
336 root_inode = minix_iget(s, MINIX_ROOT_INO);
337 if (IS_ERR(root_inode)) {
338 ret = PTR_ERR(root_inode);
339 goto out_no_root;
340 }
341
342 ret = -ENOMEM;
343 s->s_root = d_make_root(root_inode);
344 if (!s->s_root)
345 goto out_no_root;
346
347 if (!sb_rdonly(s)) {
348 if (sbi->s_version != MINIX_V3) /* s_state is now out from V3 sb */
349 ms->s_state &= ~MINIX_VALID_FS;
350 mark_buffer_dirty(bh);
351 }
352 if (!(sbi->s_mount_state & MINIX_VALID_FS))
353 printk("MINIX-fs: mounting unchecked file system, "
354 "running fsck is recommended\n");
355 else if (sbi->s_mount_state & MINIX_ERROR_FS)
356 printk("MINIX-fs: mounting file system with errors, "
357 "running fsck is recommended\n");
358
359 return 0;
360
361 out_no_root:
362 if (!silent)
363 printk("MINIX-fs: get root inode failed\n");
364 goto out_freemap;
365
366 out_no_bitmap:
367 printk("MINIX-fs: bad superblock or unable to read bitmaps\n");
368 out_freemap:
369 for (i = 0; i < sbi->s_imap_blocks; i++)
370 brelse(sbi->s_imap[i]);
371 for (i = 0; i < sbi->s_zmap_blocks; i++)
372 brelse(sbi->s_zmap[i]);
373 kfree(sbi->s_imap);
374 goto out_release;
375
376 out_no_map:
377 ret = -ENOMEM;
378 if (!silent)
379 printk("MINIX-fs: can't allocate map\n");
380 goto out_release;
381
382 out_illegal_sb:
383 if (!silent)
384 printk("MINIX-fs: bad superblock\n");
385 goto out_release;
386
387 out_no_fs:
388 if (!silent)
389 printk("VFS: Can't find a Minix filesystem V1 | V2 | V3 "
390 "on device %s.\n", s->s_id);
391 out_release:
392 brelse(bh);
393 goto out;
394
395 out_bad_hblock:
396 printk("MINIX-fs: blocksize too small for device\n");
397 goto out;
398
399 out_bad_sb:
400 printk("MINIX-fs: unable to read superblock\n");
401 out:
402 s->s_fs_info = NULL;
403 kfree(sbi);
404 return ret;
405 }
406
minix_get_tree(struct fs_context * fc)407 static int minix_get_tree(struct fs_context *fc)
408 {
409 return get_tree_bdev(fc, minix_fill_super);
410 }
411
412 static const struct fs_context_operations minix_context_ops = {
413 .get_tree = minix_get_tree,
414 .reconfigure = minix_reconfigure,
415 };
416
minix_init_fs_context(struct fs_context * fc)417 static int minix_init_fs_context(struct fs_context *fc)
418 {
419 fc->ops = &minix_context_ops;
420
421 return 0;
422 }
423
minix_statfs(struct dentry * dentry,struct kstatfs * buf)424 static int minix_statfs(struct dentry *dentry, struct kstatfs *buf)
425 {
426 struct super_block *sb = dentry->d_sb;
427 struct minix_sb_info *sbi = minix_sb(sb);
428 u64 id = huge_encode_dev(sb->s_bdev->bd_dev);
429 buf->f_type = sb->s_magic;
430 buf->f_bsize = sb->s_blocksize;
431 buf->f_blocks = (sbi->s_nzones - sbi->s_firstdatazone) << sbi->s_log_zone_size;
432 buf->f_bfree = minix_count_free_blocks(sb);
433 buf->f_bavail = buf->f_bfree;
434 buf->f_files = sbi->s_ninodes;
435 buf->f_ffree = minix_count_free_inodes(sb);
436 buf->f_namelen = sbi->s_namelen;
437 buf->f_fsid = u64_to_fsid(id);
438
439 return 0;
440 }
441
minix_get_block(struct inode * inode,sector_t block,struct buffer_head * bh_result,int create)442 static int minix_get_block(struct inode *inode, sector_t block,
443 struct buffer_head *bh_result, int create)
444 {
445 if (INODE_VERSION(inode) == MINIX_V1)
446 return V1_minix_get_block(inode, block, bh_result, create);
447 else
448 return V2_minix_get_block(inode, block, bh_result, create);
449 }
450
minix_writepages(struct address_space * mapping,struct writeback_control * wbc)451 static int minix_writepages(struct address_space *mapping,
452 struct writeback_control *wbc)
453 {
454 return mpage_writepages(mapping, wbc, minix_get_block);
455 }
456
minix_read_folio(struct file * file,struct folio * folio)457 static int minix_read_folio(struct file *file, struct folio *folio)
458 {
459 return block_read_full_folio(folio, minix_get_block);
460 }
461
minix_prepare_chunk(struct folio * folio,loff_t pos,unsigned len)462 int minix_prepare_chunk(struct folio *folio, loff_t pos, unsigned len)
463 {
464 return __block_write_begin(folio, pos, len, minix_get_block);
465 }
466
minix_write_failed(struct address_space * mapping,loff_t to)467 static void minix_write_failed(struct address_space *mapping, loff_t to)
468 {
469 struct inode *inode = mapping->host;
470
471 if (to > inode->i_size) {
472 truncate_pagecache(inode, inode->i_size);
473 minix_truncate(inode);
474 }
475 }
476
minix_write_begin(const struct kiocb * iocb,struct address_space * mapping,loff_t pos,unsigned len,struct folio ** foliop,void ** fsdata)477 static int minix_write_begin(const struct kiocb *iocb,
478 struct address_space *mapping,
479 loff_t pos, unsigned len,
480 struct folio **foliop, void **fsdata)
481 {
482 int ret;
483
484 ret = block_write_begin(mapping, pos, len, foliop, minix_get_block);
485 if (unlikely(ret))
486 minix_write_failed(mapping, pos + len);
487
488 return ret;
489 }
490
minix_bmap(struct address_space * mapping,sector_t block)491 static sector_t minix_bmap(struct address_space *mapping, sector_t block)
492 {
493 return generic_block_bmap(mapping,block,minix_get_block);
494 }
495
496 static const struct address_space_operations minix_aops = {
497 .dirty_folio = block_dirty_folio,
498 .invalidate_folio = block_invalidate_folio,
499 .read_folio = minix_read_folio,
500 .writepages = minix_writepages,
501 .write_begin = minix_write_begin,
502 .write_end = generic_write_end,
503 .migrate_folio = buffer_migrate_folio,
504 .bmap = minix_bmap,
505 .direct_IO = noop_direct_IO
506 };
507
508 static const struct inode_operations minix_symlink_inode_operations = {
509 .get_link = page_get_link,
510 .getattr = minix_getattr,
511 };
512
minix_set_inode(struct inode * inode,dev_t rdev)513 void minix_set_inode(struct inode *inode, dev_t rdev)
514 {
515 if (S_ISREG(inode->i_mode)) {
516 inode->i_op = &minix_file_inode_operations;
517 inode->i_fop = &minix_file_operations;
518 inode->i_mapping->a_ops = &minix_aops;
519 } else if (S_ISDIR(inode->i_mode)) {
520 inode->i_op = &minix_dir_inode_operations;
521 inode->i_fop = &minix_dir_operations;
522 inode->i_mapping->a_ops = &minix_aops;
523 } else if (S_ISLNK(inode->i_mode)) {
524 inode->i_op = &minix_symlink_inode_operations;
525 inode_nohighmem(inode);
526 inode->i_mapping->a_ops = &minix_aops;
527 } else if (S_ISCHR(inode->i_mode) || S_ISBLK(inode->i_mode) ||
528 S_ISFIFO(inode->i_mode) || S_ISSOCK(inode->i_mode)) {
529 init_special_inode(inode, inode->i_mode, rdev);
530 } else {
531 printk(KERN_DEBUG "MINIX-fs: Invalid file type 0%04o for inode %llu.\n",
532 inode->i_mode, inode->i_ino);
533 make_bad_inode(inode);
534 }
535 }
536
537 /*
538 * The minix V1 function to read an inode.
539 */
V1_minix_iget(struct inode * inode)540 static struct inode *V1_minix_iget(struct inode *inode)
541 {
542 struct buffer_head * bh;
543 struct minix_inode * raw_inode;
544 struct minix_inode_info *minix_inode = minix_i(inode);
545 int i;
546
547 raw_inode = minix_V1_raw_inode(inode->i_sb, inode->i_ino, &bh);
548 if (!raw_inode) {
549 iget_failed(inode);
550 return ERR_PTR(-EIO);
551 }
552 if (raw_inode->i_nlinks == 0) {
553 printk("MINIX-fs: deleted inode referenced: %llu\n",
554 inode->i_ino);
555 brelse(bh);
556 iget_failed(inode);
557 return ERR_PTR(-ESTALE);
558 }
559 inode->i_mode = raw_inode->i_mode;
560 i_uid_write(inode, raw_inode->i_uid);
561 i_gid_write(inode, raw_inode->i_gid);
562 set_nlink(inode, raw_inode->i_nlinks);
563 inode->i_size = raw_inode->i_size;
564 inode_set_mtime_to_ts(inode,
565 inode_set_atime_to_ts(inode, inode_set_ctime(inode, raw_inode->i_time, 0)));
566 inode->i_blocks = 0;
567 for (i = 0; i < 9; i++)
568 minix_inode->u.i1_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 minix V2 function to read an inode.
577 */
V2_minix_iget(struct inode * inode)578 static struct inode *V2_minix_iget(struct inode *inode)
579 {
580 struct buffer_head * bh;
581 struct minix2_inode * raw_inode;
582 struct minix_inode_info *minix_inode = minix_i(inode);
583 int i;
584
585 raw_inode = minix_V2_raw_inode(inode->i_sb, inode->i_ino, &bh);
586 if (!raw_inode) {
587 iget_failed(inode);
588 return ERR_PTR(-EIO);
589 }
590 if (raw_inode->i_nlinks == 0) {
591 printk("MINIX-fs: deleted inode referenced: %llu\n",
592 inode->i_ino);
593 brelse(bh);
594 iget_failed(inode);
595 return ERR_PTR(-ESTALE);
596 }
597 inode->i_mode = raw_inode->i_mode;
598 i_uid_write(inode, raw_inode->i_uid);
599 i_gid_write(inode, raw_inode->i_gid);
600 set_nlink(inode, raw_inode->i_nlinks);
601 inode->i_size = raw_inode->i_size;
602 inode_set_mtime(inode, raw_inode->i_mtime, 0);
603 inode_set_atime(inode, raw_inode->i_atime, 0);
604 inode_set_ctime(inode, raw_inode->i_ctime, 0);
605 inode->i_blocks = 0;
606 for (i = 0; i < 10; i++)
607 minix_inode->u.i2_data[i] = raw_inode->i_zone[i];
608 minix_set_inode(inode, old_decode_dev(raw_inode->i_zone[0]));
609 brelse(bh);
610 unlock_new_inode(inode);
611 return inode;
612 }
613
614 /*
615 * The global function to read an inode.
616 */
minix_iget(struct super_block * sb,unsigned long ino)617 struct inode *minix_iget(struct super_block *sb, unsigned long ino)
618 {
619 struct inode *inode;
620
621 inode = iget_locked(sb, ino);
622 if (!inode)
623 return ERR_PTR(-ENOMEM);
624 if (!(inode_state_read_once(inode) & I_NEW))
625 return inode;
626
627 if (INODE_VERSION(inode) == MINIX_V1)
628 return V1_minix_iget(inode);
629 else
630 return V2_minix_iget(inode);
631 }
632
633 /*
634 * The minix V1 function to synchronize an inode.
635 */
V1_minix_update_inode(struct inode * inode)636 static int V1_minix_update_inode(struct inode * inode)
637 {
638 struct buffer_head * bh;
639 struct minix_inode * raw_inode;
640 struct minix_inode_info *minix_inode = minix_i(inode);
641 int i;
642
643 raw_inode = minix_V1_raw_inode(inode->i_sb, inode->i_ino, &bh);
644 if (!raw_inode)
645 return -EIO;
646 raw_inode->i_mode = inode->i_mode;
647 raw_inode->i_uid = fs_high2lowuid(i_uid_read(inode));
648 raw_inode->i_gid = fs_high2lowgid(i_gid_read(inode));
649 raw_inode->i_nlinks = inode->i_nlink;
650 raw_inode->i_size = inode->i_size;
651 raw_inode->i_time = inode_get_mtime_sec(inode);
652 if (S_ISCHR(inode->i_mode) || S_ISBLK(inode->i_mode))
653 raw_inode->i_zone[0] = old_encode_dev(inode->i_rdev);
654 else for (i = 0; i < 9; i++)
655 raw_inode->i_zone[i] = minix_inode->u.i1_data[i];
656 mark_buffer_dirty(bh);
657 brelse(bh);
658 set_inode_metadata_writeback(inode);
659 return 0;
660 }
661
662 /*
663 * The minix V2 function to synchronize an inode.
664 */
V2_minix_update_inode(struct inode * inode)665 static int V2_minix_update_inode(struct inode * inode)
666 {
667 struct buffer_head * bh;
668 struct minix2_inode * raw_inode;
669 struct minix_inode_info *minix_inode = minix_i(inode);
670 int i;
671
672 raw_inode = minix_V2_raw_inode(inode->i_sb, inode->i_ino, &bh);
673 if (!raw_inode)
674 return -EIO;
675 raw_inode->i_mode = inode->i_mode;
676 raw_inode->i_uid = fs_high2lowuid(i_uid_read(inode));
677 raw_inode->i_gid = fs_high2lowgid(i_gid_read(inode));
678 raw_inode->i_nlinks = inode->i_nlink;
679 raw_inode->i_size = inode->i_size;
680 raw_inode->i_mtime = inode_get_mtime_sec(inode);
681 raw_inode->i_atime = inode_get_atime_sec(inode);
682 raw_inode->i_ctime = inode_get_ctime_sec(inode);
683 if (S_ISCHR(inode->i_mode) || S_ISBLK(inode->i_mode))
684 raw_inode->i_zone[0] = old_encode_dev(inode->i_rdev);
685 else for (i = 0; i < 10; i++)
686 raw_inode->i_zone[i] = minix_inode->u.i2_data[i];
687 mark_buffer_dirty(bh);
688 brelse(bh);
689 set_inode_metadata_writeback(inode);
690 return 0;
691 }
692
minix_write_inode(struct inode * inode,struct writeback_control * wbc)693 static int minix_write_inode(struct inode *inode, struct writeback_control *wbc)
694 {
695 if (INODE_VERSION(inode) == MINIX_V1)
696 return V1_minix_update_inode(inode);
697 return V2_minix_update_inode(inode);
698 }
699
minix_sync_inode_metadata(struct inode * inode,struct writeback_control * wbc)700 static int minix_sync_inode_metadata(struct inode *inode,
701 struct writeback_control *wbc)
702 {
703 int err = 0;
704 struct buffer_head *bh;
705 void *raw_inode;
706
707 if (INODE_VERSION(inode) == MINIX_V1)
708 raw_inode = minix_V1_raw_inode(inode->i_sb, inode->i_ino, &bh);
709 else
710 raw_inode = minix_V2_raw_inode(inode->i_sb, inode->i_ino, &bh);
711 if (!raw_inode)
712 return -EIO;
713 err = mmb_sync(&minix_i(inode)->i_metadata_bhs);
714 if (err)
715 goto out;
716 sync_dirty_buffer(bh);
717 if (buffer_write_io_error(bh)) {
718 printk("IO error syncing minix inode [%s:%08llx]\n",
719 inode->i_sb->s_id, inode->i_ino);
720 err = -EIO;
721 }
722 out:
723 brelse(bh);
724 return err;
725 }
726
minix_getattr(const struct mnt_idmap * idmap,const struct path * path,struct kstat * stat,u32 request_mask,unsigned int flags)727 int minix_getattr(const struct mnt_idmap *idmap, const struct path *path,
728 struct kstat *stat, u32 request_mask, unsigned int flags)
729 {
730 struct super_block *sb = path->dentry->d_sb;
731 struct inode *inode = d_inode(path->dentry);
732
733 generic_fillattr(&nop_mnt_idmap, request_mask, inode, stat);
734 if (INODE_VERSION(inode) == MINIX_V1)
735 stat->blocks = (BLOCK_SIZE / 512) * V1_minix_blocks(stat->size, sb);
736 else
737 stat->blocks = (sb->s_blocksize / 512) * V2_minix_blocks(stat->size, sb);
738 stat->blksize = sb->s_blocksize;
739 return 0;
740 }
741
742 /*
743 * The function that is called for file truncation.
744 */
minix_truncate(struct inode * inode)745 void minix_truncate(struct inode * inode)
746 {
747 if (!(S_ISREG(inode->i_mode) || S_ISDIR(inode->i_mode) || S_ISLNK(inode->i_mode)))
748 return;
749 if (INODE_VERSION(inode) == MINIX_V1)
750 V1_minix_truncate(inode);
751 else
752 V2_minix_truncate(inode);
753 }
754
755 static struct file_system_type minix_fs_type = {
756 .owner = THIS_MODULE,
757 .name = "minix",
758 .kill_sb = kill_block_super,
759 .fs_flags = FS_REQUIRES_DEV,
760 .init_fs_context = minix_init_fs_context,
761 };
762 MODULE_ALIAS_FS("minix");
763
init_minix_fs(void)764 static int __init init_minix_fs(void)
765 {
766 int err = init_inodecache();
767 if (err)
768 goto out1;
769 err = register_filesystem(&minix_fs_type);
770 if (err)
771 goto out;
772 return 0;
773 out:
774 destroy_inodecache();
775 out1:
776 return err;
777 }
778
exit_minix_fs(void)779 static void __exit exit_minix_fs(void)
780 {
781 unregister_filesystem(&minix_fs_type);
782 destroy_inodecache();
783 }
784
785 module_init(init_minix_fs)
786 module_exit(exit_minix_fs)
787 MODULE_DESCRIPTION("Minix file system");
788 MODULE_LICENSE("GPL");
789
790