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
23 static int minix_write_inode(struct inode *inode,
24 struct writeback_control *wbc);
25 static int minix_statfs(struct dentry *dentry, struct kstatfs *buf);
26 static int minix_remount (struct super_block * sb, int * flags, char * data);
27
minix_evict_inode(struct inode * inode)28 static 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
minix_put_super(struct super_block * sb)41 static 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
61 static struct kmem_cache * minix_inode_cachep;
62
minix_alloc_inode(struct super_block * sb)63 static struct inode *minix_alloc_inode(struct super_block *sb)
64 {
65 struct minix_inode_info *ei;
66 ei = kmem_cache_alloc(minix_inode_cachep, GFP_KERNEL);
67 if (!ei)
68 return NULL;
69 return &ei->vfs_inode;
70 }
71
minix_free_in_core_inode(struct inode * inode)72 static void minix_free_in_core_inode(struct inode *inode)
73 {
74 kmem_cache_free(minix_inode_cachep, minix_i(inode));
75 }
76
init_once(void * foo)77 static 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
init_inodecache(void)84 static 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
destroy_inodecache(void)96 static 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
106 static 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
minix_remount(struct super_block * sb,int * flags,char * data)116 static 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
minix_fill_super(struct super_block * s,void * data,int silent)153 static int minix_fill_super(struct super_block *s, void *data, int silent)
154 {
155 struct buffer_head *bh;
156 struct buffer_head **map;
157 struct minix_super_block *ms;
158 struct minix3_super_block *m3s = NULL;
159 unsigned long i, block;
160 struct inode *root_inode;
161 struct minix_sb_info *sbi;
162 int ret = -EINVAL;
163
164 sbi = kzalloc(sizeof(struct minix_sb_info), GFP_KERNEL);
165 if (!sbi)
166 return -ENOMEM;
167 s->s_fs_info = sbi;
168
169 BUILD_BUG_ON(32 != sizeof (struct minix_inode));
170 BUILD_BUG_ON(64 != sizeof(struct minix2_inode));
171
172 if (!sb_set_blocksize(s, BLOCK_SIZE))
173 goto out_bad_hblock;
174
175 if (!(bh = sb_bread(s, 1)))
176 goto out_bad_sb;
177
178 ms = (struct minix_super_block *) bh->b_data;
179 sbi->s_ms = ms;
180 sbi->s_sbh = bh;
181 sbi->s_mount_state = ms->s_state;
182 sbi->s_ninodes = ms->s_ninodes;
183 sbi->s_nzones = ms->s_nzones;
184 sbi->s_imap_blocks = ms->s_imap_blocks;
185 sbi->s_zmap_blocks = ms->s_zmap_blocks;
186 sbi->s_firstdatazone = ms->s_firstdatazone;
187 sbi->s_log_zone_size = ms->s_log_zone_size;
188 sbi->s_max_size = ms->s_max_size;
189 s->s_magic = ms->s_magic;
190 if (s->s_magic == MINIX_SUPER_MAGIC) {
191 sbi->s_version = MINIX_V1;
192 sbi->s_dirsize = 16;
193 sbi->s_namelen = 14;
194 s->s_max_links = MINIX_LINK_MAX;
195 } else if (s->s_magic == MINIX_SUPER_MAGIC2) {
196 sbi->s_version = MINIX_V1;
197 sbi->s_dirsize = 32;
198 sbi->s_namelen = 30;
199 s->s_max_links = MINIX_LINK_MAX;
200 } else if (s->s_magic == MINIX2_SUPER_MAGIC) {
201 sbi->s_version = MINIX_V2;
202 sbi->s_nzones = ms->s_zones;
203 sbi->s_dirsize = 16;
204 sbi->s_namelen = 14;
205 s->s_max_links = MINIX2_LINK_MAX;
206 } else if (s->s_magic == MINIX2_SUPER_MAGIC2) {
207 sbi->s_version = MINIX_V2;
208 sbi->s_nzones = ms->s_zones;
209 sbi->s_dirsize = 32;
210 sbi->s_namelen = 30;
211 s->s_max_links = MINIX2_LINK_MAX;
212 } else if ( *(__u16 *)(bh->b_data + 24) == MINIX3_SUPER_MAGIC) {
213 m3s = (struct minix3_super_block *) bh->b_data;
214 s->s_magic = m3s->s_magic;
215 sbi->s_imap_blocks = m3s->s_imap_blocks;
216 sbi->s_zmap_blocks = m3s->s_zmap_blocks;
217 sbi->s_firstdatazone = m3s->s_firstdatazone;
218 sbi->s_log_zone_size = m3s->s_log_zone_size;
219 sbi->s_max_size = m3s->s_max_size;
220 sbi->s_ninodes = m3s->s_ninodes;
221 sbi->s_nzones = m3s->s_zones;
222 sbi->s_dirsize = 64;
223 sbi->s_namelen = 60;
224 sbi->s_version = MINIX_V3;
225 sbi->s_mount_state = MINIX_VALID_FS;
226 sb_set_blocksize(s, m3s->s_blocksize);
227 s->s_max_links = MINIX2_LINK_MAX;
228 } else
229 goto out_no_fs;
230
231 /*
232 * Allocate the buffer map to keep the superblock small.
233 */
234 if (sbi->s_imap_blocks == 0 || sbi->s_zmap_blocks == 0)
235 goto out_illegal_sb;
236 i = (sbi->s_imap_blocks + sbi->s_zmap_blocks) * sizeof(bh);
237 map = kzalloc(i, GFP_KERNEL);
238 if (!map)
239 goto out_no_map;
240 sbi->s_imap = &map[0];
241 sbi->s_zmap = &map[sbi->s_imap_blocks];
242
243 block=2;
244 for (i=0 ; i < sbi->s_imap_blocks ; i++) {
245 if (!(sbi->s_imap[i]=sb_bread(s, block)))
246 goto out_no_bitmap;
247 block++;
248 }
249 for (i=0 ; i < sbi->s_zmap_blocks ; i++) {
250 if (!(sbi->s_zmap[i]=sb_bread(s, block)))
251 goto out_no_bitmap;
252 block++;
253 }
254
255 minix_set_bit(0,sbi->s_imap[0]->b_data);
256 minix_set_bit(0,sbi->s_zmap[0]->b_data);
257
258 /* Apparently minix can create filesystems that allocate more blocks for
259 * the bitmaps than needed. We simply ignore that, but verify it didn't
260 * create one with not enough blocks and bail out if so.
261 */
262 block = minix_blocks_needed(sbi->s_ninodes, s->s_blocksize);
263 if (sbi->s_imap_blocks < block) {
264 printk("MINIX-fs: file system does not have enough "
265 "imap blocks allocated. Refusing to mount.\n");
266 goto out_no_bitmap;
267 }
268
269 block = minix_blocks_needed(
270 (sbi->s_nzones - sbi->s_firstdatazone + 1),
271 s->s_blocksize);
272 if (sbi->s_zmap_blocks < block) {
273 printk("MINIX-fs: file system does not have enough "
274 "zmap blocks allocated. Refusing to mount.\n");
275 goto out_no_bitmap;
276 }
277
278 /* set up enough so that it can read an inode */
279 s->s_op = &minix_sops;
280 s->s_time_min = 0;
281 s->s_time_max = U32_MAX;
282 root_inode = minix_iget(s, MINIX_ROOT_INO);
283 if (IS_ERR(root_inode)) {
284 ret = PTR_ERR(root_inode);
285 goto out_no_root;
286 }
287
288 ret = -ENOMEM;
289 s->s_root = d_make_root(root_inode);
290 if (!s->s_root)
291 goto out_no_root;
292
293 if (!sb_rdonly(s)) {
294 if (sbi->s_version != MINIX_V3) /* s_state is now out from V3 sb */
295 ms->s_state &= ~MINIX_VALID_FS;
296 mark_buffer_dirty(bh);
297 }
298 if (!(sbi->s_mount_state & MINIX_VALID_FS))
299 printk("MINIX-fs: mounting unchecked file system, "
300 "running fsck is recommended\n");
301 else if (sbi->s_mount_state & MINIX_ERROR_FS)
302 printk("MINIX-fs: mounting file system with errors, "
303 "running fsck is recommended\n");
304
305 return 0;
306
307 out_no_root:
308 if (!silent)
309 printk("MINIX-fs: get root inode failed\n");
310 goto out_freemap;
311
312 out_no_bitmap:
313 printk("MINIX-fs: bad superblock or unable to read bitmaps\n");
314 out_freemap:
315 for (i = 0; i < sbi->s_imap_blocks; i++)
316 brelse(sbi->s_imap[i]);
317 for (i = 0; i < sbi->s_zmap_blocks; i++)
318 brelse(sbi->s_zmap[i]);
319 kfree(sbi->s_imap);
320 goto out_release;
321
322 out_no_map:
323 ret = -ENOMEM;
324 if (!silent)
325 printk("MINIX-fs: can't allocate map\n");
326 goto out_release;
327
328 out_illegal_sb:
329 if (!silent)
330 printk("MINIX-fs: bad superblock\n");
331 goto out_release;
332
333 out_no_fs:
334 if (!silent)
335 printk("VFS: Can't find a Minix filesystem V1 | V2 | V3 "
336 "on device %s.\n", s->s_id);
337 out_release:
338 brelse(bh);
339 goto out;
340
341 out_bad_hblock:
342 printk("MINIX-fs: blocksize too small for device\n");
343 goto out;
344
345 out_bad_sb:
346 printk("MINIX-fs: unable to read superblock\n");
347 out:
348 s->s_fs_info = NULL;
349 kfree(sbi);
350 return ret;
351 }
352
minix_statfs(struct dentry * dentry,struct kstatfs * buf)353 static int minix_statfs(struct dentry *dentry, struct kstatfs *buf)
354 {
355 struct super_block *sb = dentry->d_sb;
356 struct minix_sb_info *sbi = minix_sb(sb);
357 u64 id = huge_encode_dev(sb->s_bdev->bd_dev);
358 buf->f_type = sb->s_magic;
359 buf->f_bsize = sb->s_blocksize;
360 buf->f_blocks = (sbi->s_nzones - sbi->s_firstdatazone) << sbi->s_log_zone_size;
361 buf->f_bfree = minix_count_free_blocks(sb);
362 buf->f_bavail = buf->f_bfree;
363 buf->f_files = sbi->s_ninodes;
364 buf->f_ffree = minix_count_free_inodes(sb);
365 buf->f_namelen = sbi->s_namelen;
366 buf->f_fsid.val[0] = (u32)id;
367 buf->f_fsid.val[1] = (u32)(id >> 32);
368
369 return 0;
370 }
371
minix_get_block(struct inode * inode,sector_t block,struct buffer_head * bh_result,int create)372 static int minix_get_block(struct inode *inode, sector_t block,
373 struct buffer_head *bh_result, int create)
374 {
375 if (INODE_VERSION(inode) == MINIX_V1)
376 return V1_minix_get_block(inode, block, bh_result, create);
377 else
378 return V2_minix_get_block(inode, block, bh_result, create);
379 }
380
minix_writepage(struct page * page,struct writeback_control * wbc)381 static int minix_writepage(struct page *page, struct writeback_control *wbc)
382 {
383 return block_write_full_page(page, minix_get_block, wbc);
384 }
385
minix_readpage(struct file * file,struct page * page)386 static int minix_readpage(struct file *file, struct page *page)
387 {
388 return block_read_full_page(page,minix_get_block);
389 }
390
minix_prepare_chunk(struct page * page,loff_t pos,unsigned len)391 int minix_prepare_chunk(struct page *page, loff_t pos, unsigned len)
392 {
393 return __block_write_begin(page, pos, len, minix_get_block);
394 }
395
minix_write_failed(struct address_space * mapping,loff_t to)396 static void minix_write_failed(struct address_space *mapping, loff_t to)
397 {
398 struct inode *inode = mapping->host;
399
400 if (to > inode->i_size) {
401 truncate_pagecache(inode, inode->i_size);
402 minix_truncate(inode);
403 }
404 }
405
minix_write_begin(struct file * file,struct address_space * mapping,loff_t pos,unsigned len,unsigned flags,struct page ** pagep,void ** fsdata)406 static int minix_write_begin(struct file *file, struct address_space *mapping,
407 loff_t pos, unsigned len, unsigned flags,
408 struct page **pagep, void **fsdata)
409 {
410 int ret;
411
412 ret = block_write_begin(mapping, pos, len, flags, pagep,
413 minix_get_block);
414 if (unlikely(ret))
415 minix_write_failed(mapping, pos + len);
416
417 return ret;
418 }
419
minix_bmap(struct address_space * mapping,sector_t block)420 static sector_t minix_bmap(struct address_space *mapping, sector_t block)
421 {
422 return generic_block_bmap(mapping,block,minix_get_block);
423 }
424
425 static const struct address_space_operations minix_aops = {
426 .readpage = minix_readpage,
427 .writepage = minix_writepage,
428 .write_begin = minix_write_begin,
429 .write_end = generic_write_end,
430 .bmap = minix_bmap
431 };
432
433 static const struct inode_operations minix_symlink_inode_operations = {
434 .get_link = page_get_link,
435 .getattr = minix_getattr,
436 };
437
minix_set_inode(struct inode * inode,dev_t rdev)438 void minix_set_inode(struct inode *inode, dev_t rdev)
439 {
440 if (S_ISREG(inode->i_mode)) {
441 inode->i_op = &minix_file_inode_operations;
442 inode->i_fop = &minix_file_operations;
443 inode->i_mapping->a_ops = &minix_aops;
444 } else if (S_ISDIR(inode->i_mode)) {
445 inode->i_op = &minix_dir_inode_operations;
446 inode->i_fop = &minix_dir_operations;
447 inode->i_mapping->a_ops = &minix_aops;
448 } else if (S_ISLNK(inode->i_mode)) {
449 inode->i_op = &minix_symlink_inode_operations;
450 inode_nohighmem(inode);
451 inode->i_mapping->a_ops = &minix_aops;
452 } else
453 init_special_inode(inode, inode->i_mode, rdev);
454 }
455
456 /*
457 * The minix V1 function to read an inode.
458 */
V1_minix_iget(struct inode * inode)459 static struct inode *V1_minix_iget(struct inode *inode)
460 {
461 struct buffer_head * bh;
462 struct minix_inode * raw_inode;
463 struct minix_inode_info *minix_inode = minix_i(inode);
464 int i;
465
466 raw_inode = minix_V1_raw_inode(inode->i_sb, inode->i_ino, &bh);
467 if (!raw_inode) {
468 iget_failed(inode);
469 return ERR_PTR(-EIO);
470 }
471 inode->i_mode = raw_inode->i_mode;
472 i_uid_write(inode, raw_inode->i_uid);
473 i_gid_write(inode, raw_inode->i_gid);
474 set_nlink(inode, raw_inode->i_nlinks);
475 inode->i_size = raw_inode->i_size;
476 inode->i_mtime.tv_sec = inode->i_atime.tv_sec = inode->i_ctime.tv_sec = raw_inode->i_time;
477 inode->i_mtime.tv_nsec = 0;
478 inode->i_atime.tv_nsec = 0;
479 inode->i_ctime.tv_nsec = 0;
480 inode->i_blocks = 0;
481 for (i = 0; i < 9; i++)
482 minix_inode->u.i1_data[i] = raw_inode->i_zone[i];
483 minix_set_inode(inode, old_decode_dev(raw_inode->i_zone[0]));
484 brelse(bh);
485 unlock_new_inode(inode);
486 return inode;
487 }
488
489 /*
490 * The minix V2 function to read an inode.
491 */
V2_minix_iget(struct inode * inode)492 static struct inode *V2_minix_iget(struct inode *inode)
493 {
494 struct buffer_head * bh;
495 struct minix2_inode * raw_inode;
496 struct minix_inode_info *minix_inode = minix_i(inode);
497 int i;
498
499 raw_inode = minix_V2_raw_inode(inode->i_sb, inode->i_ino, &bh);
500 if (!raw_inode) {
501 iget_failed(inode);
502 return ERR_PTR(-EIO);
503 }
504 inode->i_mode = raw_inode->i_mode;
505 i_uid_write(inode, raw_inode->i_uid);
506 i_gid_write(inode, raw_inode->i_gid);
507 set_nlink(inode, raw_inode->i_nlinks);
508 inode->i_size = raw_inode->i_size;
509 inode->i_mtime.tv_sec = raw_inode->i_mtime;
510 inode->i_atime.tv_sec = raw_inode->i_atime;
511 inode->i_ctime.tv_sec = raw_inode->i_ctime;
512 inode->i_mtime.tv_nsec = 0;
513 inode->i_atime.tv_nsec = 0;
514 inode->i_ctime.tv_nsec = 0;
515 inode->i_blocks = 0;
516 for (i = 0; i < 10; i++)
517 minix_inode->u.i2_data[i] = raw_inode->i_zone[i];
518 minix_set_inode(inode, old_decode_dev(raw_inode->i_zone[0]));
519 brelse(bh);
520 unlock_new_inode(inode);
521 return inode;
522 }
523
524 /*
525 * The global function to read an inode.
526 */
minix_iget(struct super_block * sb,unsigned long ino)527 struct inode *minix_iget(struct super_block *sb, unsigned long ino)
528 {
529 struct inode *inode;
530
531 inode = iget_locked(sb, ino);
532 if (!inode)
533 return ERR_PTR(-ENOMEM);
534 if (!(inode->i_state & I_NEW))
535 return inode;
536
537 if (INODE_VERSION(inode) == MINIX_V1)
538 return V1_minix_iget(inode);
539 else
540 return V2_minix_iget(inode);
541 }
542
543 /*
544 * The minix V1 function to synchronize an inode.
545 */
V1_minix_update_inode(struct inode * inode)546 static struct buffer_head * V1_minix_update_inode(struct inode * inode)
547 {
548 struct buffer_head * bh;
549 struct minix_inode * raw_inode;
550 struct minix_inode_info *minix_inode = minix_i(inode);
551 int i;
552
553 raw_inode = minix_V1_raw_inode(inode->i_sb, inode->i_ino, &bh);
554 if (!raw_inode)
555 return NULL;
556 raw_inode->i_mode = inode->i_mode;
557 raw_inode->i_uid = fs_high2lowuid(i_uid_read(inode));
558 raw_inode->i_gid = fs_high2lowgid(i_gid_read(inode));
559 raw_inode->i_nlinks = inode->i_nlink;
560 raw_inode->i_size = inode->i_size;
561 raw_inode->i_time = inode->i_mtime.tv_sec;
562 if (S_ISCHR(inode->i_mode) || S_ISBLK(inode->i_mode))
563 raw_inode->i_zone[0] = old_encode_dev(inode->i_rdev);
564 else for (i = 0; i < 9; i++)
565 raw_inode->i_zone[i] = minix_inode->u.i1_data[i];
566 mark_buffer_dirty(bh);
567 return bh;
568 }
569
570 /*
571 * The minix V2 function to synchronize an inode.
572 */
V2_minix_update_inode(struct inode * inode)573 static struct buffer_head * V2_minix_update_inode(struct inode * inode)
574 {
575 struct buffer_head * bh;
576 struct minix2_inode * raw_inode;
577 struct minix_inode_info *minix_inode = minix_i(inode);
578 int i;
579
580 raw_inode = minix_V2_raw_inode(inode->i_sb, inode->i_ino, &bh);
581 if (!raw_inode)
582 return NULL;
583 raw_inode->i_mode = inode->i_mode;
584 raw_inode->i_uid = fs_high2lowuid(i_uid_read(inode));
585 raw_inode->i_gid = fs_high2lowgid(i_gid_read(inode));
586 raw_inode->i_nlinks = inode->i_nlink;
587 raw_inode->i_size = inode->i_size;
588 raw_inode->i_mtime = inode->i_mtime.tv_sec;
589 raw_inode->i_atime = inode->i_atime.tv_sec;
590 raw_inode->i_ctime = inode->i_ctime.tv_sec;
591 if (S_ISCHR(inode->i_mode) || S_ISBLK(inode->i_mode))
592 raw_inode->i_zone[0] = old_encode_dev(inode->i_rdev);
593 else for (i = 0; i < 10; i++)
594 raw_inode->i_zone[i] = minix_inode->u.i2_data[i];
595 mark_buffer_dirty(bh);
596 return bh;
597 }
598
minix_write_inode(struct inode * inode,struct writeback_control * wbc)599 static int minix_write_inode(struct inode *inode, struct writeback_control *wbc)
600 {
601 int err = 0;
602 struct buffer_head *bh;
603
604 if (INODE_VERSION(inode) == MINIX_V1)
605 bh = V1_minix_update_inode(inode);
606 else
607 bh = V2_minix_update_inode(inode);
608 if (!bh)
609 return -EIO;
610 if (wbc->sync_mode == WB_SYNC_ALL && buffer_dirty(bh)) {
611 sync_dirty_buffer(bh);
612 if (buffer_req(bh) && !buffer_uptodate(bh)) {
613 printk("IO error syncing minix inode [%s:%08lx]\n",
614 inode->i_sb->s_id, inode->i_ino);
615 err = -EIO;
616 }
617 }
618 brelse (bh);
619 return err;
620 }
621
minix_getattr(const struct path * path,struct kstat * stat,u32 request_mask,unsigned int flags)622 int minix_getattr(const struct path *path, struct kstat *stat,
623 u32 request_mask, unsigned int flags)
624 {
625 struct super_block *sb = path->dentry->d_sb;
626 struct inode *inode = d_inode(path->dentry);
627
628 generic_fillattr(inode, stat);
629 if (INODE_VERSION(inode) == MINIX_V1)
630 stat->blocks = (BLOCK_SIZE / 512) * V1_minix_blocks(stat->size, sb);
631 else
632 stat->blocks = (sb->s_blocksize / 512) * V2_minix_blocks(stat->size, sb);
633 stat->blksize = sb->s_blocksize;
634 return 0;
635 }
636
637 /*
638 * The function that is called for file truncation.
639 */
minix_truncate(struct inode * inode)640 void minix_truncate(struct inode * inode)
641 {
642 if (!(S_ISREG(inode->i_mode) || S_ISDIR(inode->i_mode) || S_ISLNK(inode->i_mode)))
643 return;
644 if (INODE_VERSION(inode) == MINIX_V1)
645 V1_minix_truncate(inode);
646 else
647 V2_minix_truncate(inode);
648 }
649
minix_mount(struct file_system_type * fs_type,int flags,const char * dev_name,void * data)650 static struct dentry *minix_mount(struct file_system_type *fs_type,
651 int flags, const char *dev_name, void *data)
652 {
653 return mount_bdev(fs_type, flags, dev_name, data, minix_fill_super);
654 }
655
656 static struct file_system_type minix_fs_type = {
657 .owner = THIS_MODULE,
658 .name = "minix",
659 .mount = minix_mount,
660 .kill_sb = kill_block_super,
661 .fs_flags = FS_REQUIRES_DEV,
662 };
663 MODULE_ALIAS_FS("minix");
664
init_minix_fs(void)665 static int __init init_minix_fs(void)
666 {
667 int err = init_inodecache();
668 if (err)
669 goto out1;
670 err = register_filesystem(&minix_fs_type);
671 if (err)
672 goto out;
673 return 0;
674 out:
675 destroy_inodecache();
676 out1:
677 return err;
678 }
679
exit_minix_fs(void)680 static void __exit exit_minix_fs(void)
681 {
682 unregister_filesystem(&minix_fs_type);
683 destroy_inodecache();
684 }
685
686 module_init(init_minix_fs)
687 module_exit(exit_minix_fs)
688 MODULE_LICENSE("GPL");
689
690