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 | |
24 | static int minix_write_inode(struct inode *inode, |
25 | struct writeback_control *wbc); |
26 | static int minix_statfs(struct dentry *dentry, struct kstatfs *buf); |
27 | static int minix_remount (struct super_block * sb, int * flags, char * data); |
28 | |
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 | |
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(bh: sbi->s_sbh); |
51 | } |
52 | for (i = 0; i < sbi->s_imap_blocks; i++) |
53 | brelse(bh: sbi->s_imap[i]); |
54 | for (i = 0; i < sbi->s_zmap_blocks; i++) |
55 | brelse(bh: sbi->s_zmap[i]); |
56 | brelse (bh: sbi->s_sbh); |
57 | kfree(objp: sbi->s_imap); |
58 | sb->s_fs_info = NULL; |
59 | kfree(objp: sbi); |
60 | } |
61 | |
62 | static struct kmem_cache * minix_inode_cachep; |
63 | |
64 | static struct inode *minix_alloc_inode(struct super_block *sb) |
65 | { |
66 | struct minix_inode_info *ei; |
67 | ei = alloc_inode_sb(sb, cache: minix_inode_cachep, GFP_KERNEL); |
68 | if (!ei) |
69 | return NULL; |
70 | return &ei->vfs_inode; |
71 | } |
72 | |
73 | static void minix_free_in_core_inode(struct inode *inode) |
74 | { |
75 | kmem_cache_free(s: minix_inode_cachep, objp: minix_i(inode)); |
76 | } |
77 | |
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 | |
85 | static int __init init_inodecache(void) |
86 | { |
87 | minix_inode_cachep = kmem_cache_create(name: "minix_inode_cache" , |
88 | size: sizeof(struct minix_inode_info), |
89 | align: 0, flags: (SLAB_RECLAIM_ACCOUNT| |
90 | SLAB_ACCOUNT), |
91 | ctor: init_once); |
92 | if (minix_inode_cachep == NULL) |
93 | return -ENOMEM; |
94 | return 0; |
95 | } |
96 | |
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(s: 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 | .remount_fs = minix_remount, |
115 | }; |
116 | |
117 | static 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(bh: 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(bh: 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 | |
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 | |
173 | static 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(size: 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(sb: s, block: 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(sb: 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(size: 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(sb: 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(sb: s, block))) |
272 | goto out_no_bitmap; |
273 | block++; |
274 | } |
275 | |
276 | minix_set_bit(nr: 0,addr: sbi->s_imap[0]->b_data); |
277 | minix_set_bit(nr: 0,addr: 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(bits: sbi->s_ninodes, blocksize: 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 | bits: (sbi->s_nzones - sbi->s_firstdatazone + 1), |
292 | blocksize: 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(ptr: root_inode)) { |
305 | ret = PTR_ERR(ptr: 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(sb: 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 | |
328 | out_no_root: |
329 | if (!silent) |
330 | printk("MINIX-fs: get root inode failed\n" ); |
331 | goto out_freemap; |
332 | |
333 | out_no_bitmap: |
334 | printk("MINIX-fs: bad superblock or unable to read bitmaps\n" ); |
335 | out_freemap: |
336 | for (i = 0; i < sbi->s_imap_blocks; i++) |
337 | brelse(bh: sbi->s_imap[i]); |
338 | for (i = 0; i < sbi->s_zmap_blocks; i++) |
339 | brelse(bh: sbi->s_zmap[i]); |
340 | kfree(objp: sbi->s_imap); |
341 | goto out_release; |
342 | |
343 | out_no_map: |
344 | ret = -ENOMEM; |
345 | if (!silent) |
346 | printk("MINIX-fs: can't allocate map\n" ); |
347 | goto out_release; |
348 | |
349 | out_illegal_sb: |
350 | if (!silent) |
351 | printk("MINIX-fs: bad superblock\n" ); |
352 | goto out_release; |
353 | |
354 | out_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); |
358 | out_release: |
359 | brelse(bh); |
360 | goto out; |
361 | |
362 | out_bad_hblock: |
363 | printk("MINIX-fs: blocksize too small for device\n" ); |
364 | goto out; |
365 | |
366 | out_bad_sb: |
367 | printk("MINIX-fs: unable to read superblock\n" ); |
368 | out: |
369 | s->s_fs_info = NULL; |
370 | kfree(objp: sbi); |
371 | return ret; |
372 | } |
373 | |
374 | static 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(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(v: id); |
388 | |
389 | return 0; |
390 | } |
391 | |
392 | static 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 | |
401 | static int minix_writepages(struct address_space *mapping, |
402 | struct writeback_control *wbc) |
403 | { |
404 | return mpage_writepages(mapping, wbc, get_block: minix_get_block); |
405 | } |
406 | |
407 | static int minix_read_folio(struct file *file, struct folio *folio) |
408 | { |
409 | return block_read_full_folio(folio, minix_get_block); |
410 | } |
411 | |
412 | int minix_prepare_chunk(struct page *page, loff_t pos, unsigned len) |
413 | { |
414 | return __block_write_begin(page, pos, len, get_block: minix_get_block); |
415 | } |
416 | |
417 | static 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, new: inode->i_size); |
423 | minix_truncate(inode); |
424 | } |
425 | } |
426 | |
427 | static 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, get_block: minix_get_block); |
434 | if (unlikely(ret)) |
435 | minix_write_failed(mapping, to: pos + len); |
436 | |
437 | return ret; |
438 | } |
439 | |
440 | static sector_t minix_bmap(struct address_space *mapping, sector_t block) |
441 | { |
442 | return generic_block_bmap(mapping,block,minix_get_block); |
443 | } |
444 | |
445 | static 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 | |
457 | static const struct inode_operations minix_symlink_inode_operations = { |
458 | .get_link = page_get_link, |
459 | .getattr = minix_getattr, |
460 | }; |
461 | |
462 | void 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 | */ |
483 | static 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(error: -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(error: -ESTALE); |
501 | } |
502 | inode->i_mode = raw_inode->i_mode; |
503 | i_uid_write(inode, uid: raw_inode->i_uid); |
504 | i_gid_write(inode, gid: raw_inode->i_gid); |
505 | set_nlink(inode, nlink: raw_inode->i_nlinks); |
506 | inode->i_size = raw_inode->i_size; |
507 | inode_set_mtime_to_ts(inode, |
508 | ts: inode_set_atime_to_ts(inode, ts: inode_set_ctime(inode, sec: raw_inode->i_time, nsec: 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, rdev: old_decode_dev(val: 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 | */ |
521 | static 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(error: -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(error: -ESTALE); |
539 | } |
540 | inode->i_mode = raw_inode->i_mode; |
541 | i_uid_write(inode, uid: raw_inode->i_uid); |
542 | i_gid_write(inode, gid: raw_inode->i_gid); |
543 | set_nlink(inode, nlink: raw_inode->i_nlinks); |
544 | inode->i_size = raw_inode->i_size; |
545 | inode_set_mtime(inode, sec: raw_inode->i_mtime, nsec: 0); |
546 | inode_set_atime(inode, sec: raw_inode->i_atime, nsec: 0); |
547 | inode_set_ctime(inode, sec: raw_inode->i_ctime, nsec: 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, rdev: old_decode_dev(val: 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 | */ |
560 | struct 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(error: -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 | */ |
579 | static 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(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 | */ |
606 | static 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(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 | |
632 | static 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 | |
655 | int 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(dentry: 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 | */ |
673 | void 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 | |
683 | static 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, fill_super: minix_fill_super); |
687 | } |
688 | |
689 | static 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 | }; |
696 | MODULE_ALIAS_FS("minix" ); |
697 | |
698 | static 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; |
707 | out: |
708 | destroy_inodecache(); |
709 | out1: |
710 | return err; |
711 | } |
712 | |
713 | static void __exit exit_minix_fs(void) |
714 | { |
715 | unregister_filesystem(&minix_fs_type); |
716 | destroy_inodecache(); |
717 | } |
718 | |
719 | module_init(init_minix_fs) |
720 | module_exit(exit_minix_fs) |
721 | MODULE_LICENSE("GPL" ); |
722 | |
723 | |