1
2
3
4
5
6
7
8
9
10
11
12
13#include <linux/module.h>
14#include "minix.h"
15#include <linux/buffer_head.h>
16#include <linux/slab.h>
17#include <linux/init.h>
18#include <linux/highuid.h>
19#include <linux/vfs.h>
20#include <linux/writeback.h>
21
22static int minix_write_inode(struct inode *inode,
23 struct writeback_control *wbc);
24static int minix_statfs(struct dentry *dentry, struct kstatfs *buf);
25static int minix_remount (struct super_block * sb, int * flags, char * data);
26
27static void minix_evict_inode(struct inode *inode)
28{
29 truncate_inode_pages(&inode->i_data, 0);
30 if (!inode->i_nlink) {
31 inode->i_size = 0;
32 minix_truncate(inode);
33 }
34 invalidate_inode_buffers(inode);
35 end_writeback(inode);
36 if (!inode->i_nlink)
37 minix_free_inode(inode);
38}
39
40static void minix_put_super(struct super_block *sb)
41{
42 int i;
43 struct minix_sb_info *sbi = minix_sb(sb);
44
45 if (!(sb->s_flags & MS_RDONLY)) {
46 if (sbi->s_version != MINIX_V3)
47 sbi->s_ms->s_state = sbi->s_mount_state;
48 mark_buffer_dirty(sbi->s_sbh);
49 }
50 for (i = 0; i < sbi->s_imap_blocks; i++)
51 brelse(sbi->s_imap[i]);
52 for (i = 0; i < sbi->s_zmap_blocks; i++)
53 brelse(sbi->s_zmap[i]);
54 brelse (sbi->s_sbh);
55 kfree(sbi->s_imap);
56 sb->s_fs_info = NULL;
57 kfree(sbi);
58}
59
60static struct kmem_cache * minix_inode_cachep;
61
62static struct inode *minix_alloc_inode(struct super_block *sb)
63{
64 struct minix_inode_info *ei;
65 ei = (struct minix_inode_info *)kmem_cache_alloc(minix_inode_cachep, GFP_KERNEL);
66 if (!ei)
67 return NULL;
68 return &ei->vfs_inode;
69}
70
71static void minix_i_callback(struct rcu_head *head)
72{
73 struct inode *inode = container_of(head, struct inode, i_rcu);
74 INIT_LIST_HEAD(&inode->i_dentry);
75 kmem_cache_free(minix_inode_cachep, minix_i(inode));
76}
77
78static void minix_destroy_inode(struct inode *inode)
79{
80 call_rcu(&inode->i_rcu, minix_i_callback);
81}
82
83static void init_once(void *foo)
84{
85 struct minix_inode_info *ei = (struct minix_inode_info *) foo;
86
87 inode_init_once(&ei->vfs_inode);
88}
89
90static int init_inodecache(void)
91{
92 minix_inode_cachep = kmem_cache_create("minix_inode_cache",
93 sizeof(struct minix_inode_info),
94 0, (SLAB_RECLAIM_ACCOUNT|
95 SLAB_MEM_SPREAD),
96 init_once);
97 if (minix_inode_cachep == NULL)
98 return -ENOMEM;
99 return 0;
100}
101
102static void destroy_inodecache(void)
103{
104 kmem_cache_destroy(minix_inode_cachep);
105}
106
107static const struct super_operations minix_sops = {
108 .alloc_inode = minix_alloc_inode,
109 .destroy_inode = minix_destroy_inode,
110 .write_inode = minix_write_inode,
111 .evict_inode = minix_evict_inode,
112 .put_super = minix_put_super,
113 .statfs = minix_statfs,
114 .remount_fs = minix_remount,
115};
116
117static int minix_remount (struct super_block * sb, int * flags, char * data)
118{
119 struct minix_sb_info * sbi = minix_sb(sb);
120 struct minix_super_block * ms;
121
122 ms = sbi->s_ms;
123 if ((*flags & MS_RDONLY) == (sb->s_flags & MS_RDONLY))
124 return 0;
125 if (*flags & MS_RDONLY) {
126 if (ms->s_state & MINIX_VALID_FS ||
127 !(sbi->s_mount_state & MINIX_VALID_FS))
128 return 0;
129
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
135 if (sbi->s_version != MINIX_V3) {
136 sbi->s_mount_state = ms->s_state;
137 ms->s_state &= ~MINIX_VALID_FS;
138 } else {
139 sbi->s_mount_state = MINIX_VALID_FS;
140 }
141 mark_buffer_dirty(sbi->s_sbh);
142
143 if (!(sbi->s_mount_state & MINIX_VALID_FS))
144 printk("MINIX-fs warning: remounting unchecked fs, "
145 "running fsck is recommended\n");
146 else if ((sbi->s_mount_state & MINIX_ERROR_FS))
147 printk("MINIX-fs warning: remounting fs with errors, "
148 "running fsck is recommended\n");
149 }
150 return 0;
151}
152
153static 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 sbi->s_link_max = 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 sbi->s_link_max = 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 sbi->s_link_max = 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 sbi->s_link_max = 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_link_max = MINIX2_LINK_MAX;
226 sbi->s_mount_state = MINIX_VALID_FS;
227 sb_set_blocksize(s, m3s->s_blocksize);
228 } else
229 goto out_no_fs;
230
231
232
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
259 s->s_op = &minix_sops;
260 root_inode = minix_iget(s, MINIX_ROOT_INO);
261 if (IS_ERR(root_inode)) {
262 ret = PTR_ERR(root_inode);
263 goto out_no_root;
264 }
265
266 ret = -ENOMEM;
267 s->s_root = d_alloc_root(root_inode);
268 if (!s->s_root)
269 goto out_iput;
270
271 if (!(s->s_flags & MS_RDONLY)) {
272 if (sbi->s_version != MINIX_V3)
273 ms->s_state &= ~MINIX_VALID_FS;
274 mark_buffer_dirty(bh);
275 }
276 if (!(sbi->s_mount_state & MINIX_VALID_FS))
277 printk("MINIX-fs: mounting unchecked file system, "
278 "running fsck is recommended\n");
279 else if (sbi->s_mount_state & MINIX_ERROR_FS)
280 printk("MINIX-fs: mounting file system with errors, "
281 "running fsck is recommended\n");
282 return 0;
283
284out_iput:
285 iput(root_inode);
286 goto out_freemap;
287
288out_no_root:
289 if (!silent)
290 printk("MINIX-fs: get root inode failed\n");
291 goto out_freemap;
292
293out_no_bitmap:
294 printk("MINIX-fs: bad superblock or unable to read bitmaps\n");
295out_freemap:
296 for (i = 0; i < sbi->s_imap_blocks; i++)
297 brelse(sbi->s_imap[i]);
298 for (i = 0; i < sbi->s_zmap_blocks; i++)
299 brelse(sbi->s_zmap[i]);
300 kfree(sbi->s_imap);
301 goto out_release;
302
303out_no_map:
304 ret = -ENOMEM;
305 if (!silent)
306 printk("MINIX-fs: can't allocate map\n");
307 goto out_release;
308
309out_illegal_sb:
310 if (!silent)
311 printk("MINIX-fs: bad superblock\n");
312 goto out_release;
313
314out_no_fs:
315 if (!silent)
316 printk("VFS: Can't find a Minix filesystem V1 | V2 | V3 "
317 "on device %s.\n", s->s_id);
318out_release:
319 brelse(bh);
320 goto out;
321
322out_bad_hblock:
323 printk("MINIX-fs: blocksize too small for device\n");
324 goto out;
325
326out_bad_sb:
327 printk("MINIX-fs: unable to read superblock\n");
328out:
329 s->s_fs_info = NULL;
330 kfree(sbi);
331 return ret;
332}
333
334static int minix_statfs(struct dentry *dentry, struct kstatfs *buf)
335{
336 struct super_block *sb = dentry->d_sb;
337 struct minix_sb_info *sbi = minix_sb(sb);
338 u64 id = huge_encode_dev(sb->s_bdev->bd_dev);
339 buf->f_type = sb->s_magic;
340 buf->f_bsize = sb->s_blocksize;
341 buf->f_blocks = (sbi->s_nzones - sbi->s_firstdatazone) << sbi->s_log_zone_size;
342 buf->f_bfree = minix_count_free_blocks(sbi);
343 buf->f_bavail = buf->f_bfree;
344 buf->f_files = sbi->s_ninodes;
345 buf->f_ffree = minix_count_free_inodes(sbi);
346 buf->f_namelen = sbi->s_namelen;
347 buf->f_fsid.val[0] = (u32)id;
348 buf->f_fsid.val[1] = (u32)(id >> 32);
349
350 return 0;
351}
352
353static int minix_get_block(struct inode *inode, sector_t block,
354 struct buffer_head *bh_result, int create)
355{
356 if (INODE_VERSION(inode) == MINIX_V1)
357 return V1_minix_get_block(inode, block, bh_result, create);
358 else
359 return V2_minix_get_block(inode, block, bh_result, create);
360}
361
362static int minix_writepage(struct page *page, struct writeback_control *wbc)
363{
364 return block_write_full_page(page, minix_get_block, wbc);
365}
366
367static int minix_readpage(struct file *file, struct page *page)
368{
369 return block_read_full_page(page,minix_get_block);
370}
371
372int minix_prepare_chunk(struct page *page, loff_t pos, unsigned len)
373{
374 return __block_write_begin(page, pos, len, minix_get_block);
375}
376
377static int minix_write_begin(struct file *file, struct address_space *mapping,
378 loff_t pos, unsigned len, unsigned flags,
379 struct page **pagep, void **fsdata)
380{
381 int ret;
382
383 ret = block_write_begin(mapping, pos, len, flags, pagep,
384 minix_get_block);
385 if (unlikely(ret)) {
386 loff_t isize = mapping->host->i_size;
387 if (pos + len > isize)
388 vmtruncate(mapping->host, isize);
389 }
390
391 return ret;
392}
393
394static sector_t minix_bmap(struct address_space *mapping, sector_t block)
395{
396 return generic_block_bmap(mapping,block,minix_get_block);
397}
398
399static const struct address_space_operations minix_aops = {
400 .readpage = minix_readpage,
401 .writepage = minix_writepage,
402 .sync_page = block_sync_page,
403 .write_begin = minix_write_begin,
404 .write_end = generic_write_end,
405 .bmap = minix_bmap
406};
407
408static const struct inode_operations minix_symlink_inode_operations = {
409 .readlink = generic_readlink,
410 .follow_link = page_follow_link_light,
411 .put_link = page_put_link,
412 .getattr = minix_getattr,
413};
414
415void minix_set_inode(struct inode *inode, dev_t rdev)
416{
417 if (S_ISREG(inode->i_mode)) {
418 inode->i_op = &minix_file_inode_operations;
419 inode->i_fop = &minix_file_operations;
420 inode->i_mapping->a_ops = &minix_aops;
421 } else if (S_ISDIR(inode->i_mode)) {
422 inode->i_op = &minix_dir_inode_operations;
423 inode->i_fop = &minix_dir_operations;
424 inode->i_mapping->a_ops = &minix_aops;
425 } else if (S_ISLNK(inode->i_mode)) {
426 inode->i_op = &minix_symlink_inode_operations;
427 inode->i_mapping->a_ops = &minix_aops;
428 } else
429 init_special_inode(inode, inode->i_mode, rdev);
430}
431
432
433
434
435static struct inode *V1_minix_iget(struct inode *inode)
436{
437 struct buffer_head * bh;
438 struct minix_inode * raw_inode;
439 struct minix_inode_info *minix_inode = minix_i(inode);
440 int i;
441
442 raw_inode = minix_V1_raw_inode(inode->i_sb, inode->i_ino, &bh);
443 if (!raw_inode) {
444 iget_failed(inode);
445 return ERR_PTR(-EIO);
446 }
447 inode->i_mode = raw_inode->i_mode;
448 inode->i_uid = (uid_t)raw_inode->i_uid;
449 inode->i_gid = (gid_t)raw_inode->i_gid;
450 inode->i_nlink = raw_inode->i_nlinks;
451 inode->i_size = raw_inode->i_size;
452 inode->i_mtime.tv_sec = inode->i_atime.tv_sec = inode->i_ctime.tv_sec = raw_inode->i_time;
453 inode->i_mtime.tv_nsec = 0;
454 inode->i_atime.tv_nsec = 0;
455 inode->i_ctime.tv_nsec = 0;
456 inode->i_blocks = 0;
457 for (i = 0; i < 9; i++)
458 minix_inode->u.i1_data[i] = raw_inode->i_zone[i];
459 minix_set_inode(inode, old_decode_dev(raw_inode->i_zone[0]));
460 brelse(bh);
461 unlock_new_inode(inode);
462 return inode;
463}
464
465
466
467
468static struct inode *V2_minix_iget(struct inode *inode)
469{
470 struct buffer_head * bh;
471 struct minix2_inode * raw_inode;
472 struct minix_inode_info *minix_inode = minix_i(inode);
473 int i;
474
475 raw_inode = minix_V2_raw_inode(inode->i_sb, inode->i_ino, &bh);
476 if (!raw_inode) {
477 iget_failed(inode);
478 return ERR_PTR(-EIO);
479 }
480 inode->i_mode = raw_inode->i_mode;
481 inode->i_uid = (uid_t)raw_inode->i_uid;
482 inode->i_gid = (gid_t)raw_inode->i_gid;
483 inode->i_nlink = raw_inode->i_nlinks;
484 inode->i_size = raw_inode->i_size;
485 inode->i_mtime.tv_sec = raw_inode->i_mtime;
486 inode->i_atime.tv_sec = raw_inode->i_atime;
487 inode->i_ctime.tv_sec = raw_inode->i_ctime;
488 inode->i_mtime.tv_nsec = 0;
489 inode->i_atime.tv_nsec = 0;
490 inode->i_ctime.tv_nsec = 0;
491 inode->i_blocks = 0;
492 for (i = 0; i < 10; i++)
493 minix_inode->u.i2_data[i] = raw_inode->i_zone[i];
494 minix_set_inode(inode, old_decode_dev(raw_inode->i_zone[0]));
495 brelse(bh);
496 unlock_new_inode(inode);
497 return inode;
498}
499
500
501
502
503struct inode *minix_iget(struct super_block *sb, unsigned long ino)
504{
505 struct inode *inode;
506
507 inode = iget_locked(sb, ino);
508 if (!inode)
509 return ERR_PTR(-ENOMEM);
510 if (!(inode->i_state & I_NEW))
511 return inode;
512
513 if (INODE_VERSION(inode) == MINIX_V1)
514 return V1_minix_iget(inode);
515 else
516 return V2_minix_iget(inode);
517}
518
519
520
521
522static struct buffer_head * V1_minix_update_inode(struct inode * inode)
523{
524 struct buffer_head * bh;
525 struct minix_inode * raw_inode;
526 struct minix_inode_info *minix_inode = minix_i(inode);
527 int i;
528
529 raw_inode = minix_V1_raw_inode(inode->i_sb, inode->i_ino, &bh);
530 if (!raw_inode)
531 return NULL;
532 raw_inode->i_mode = inode->i_mode;
533 raw_inode->i_uid = fs_high2lowuid(inode->i_uid);
534 raw_inode->i_gid = fs_high2lowgid(inode->i_gid);
535 raw_inode->i_nlinks = inode->i_nlink;
536 raw_inode->i_size = inode->i_size;
537 raw_inode->i_time = inode->i_mtime.tv_sec;
538 if (S_ISCHR(inode->i_mode) || S_ISBLK(inode->i_mode))
539 raw_inode->i_zone[0] = old_encode_dev(inode->i_rdev);
540 else for (i = 0; i < 9; i++)
541 raw_inode->i_zone[i] = minix_inode->u.i1_data[i];
542 mark_buffer_dirty(bh);
543 return bh;
544}
545
546
547
548
549static struct buffer_head * V2_minix_update_inode(struct inode * inode)
550{
551 struct buffer_head * bh;
552 struct minix2_inode * raw_inode;
553 struct minix_inode_info *minix_inode = minix_i(inode);
554 int i;
555
556 raw_inode = minix_V2_raw_inode(inode->i_sb, inode->i_ino, &bh);
557 if (!raw_inode)
558 return NULL;
559 raw_inode->i_mode = inode->i_mode;
560 raw_inode->i_uid = fs_high2lowuid(inode->i_uid);
561 raw_inode->i_gid = fs_high2lowgid(inode->i_gid);
562 raw_inode->i_nlinks = inode->i_nlink;
563 raw_inode->i_size = inode->i_size;
564 raw_inode->i_mtime = inode->i_mtime.tv_sec;
565 raw_inode->i_atime = inode->i_atime.tv_sec;
566 raw_inode->i_ctime = inode->i_ctime.tv_sec;
567 if (S_ISCHR(inode->i_mode) || S_ISBLK(inode->i_mode))
568 raw_inode->i_zone[0] = old_encode_dev(inode->i_rdev);
569 else for (i = 0; i < 10; i++)
570 raw_inode->i_zone[i] = minix_inode->u.i2_data[i];
571 mark_buffer_dirty(bh);
572 return bh;
573}
574
575static int minix_write_inode(struct inode *inode, struct writeback_control *wbc)
576{
577 int err = 0;
578 struct buffer_head *bh;
579
580 if (INODE_VERSION(inode) == MINIX_V1)
581 bh = V1_minix_update_inode(inode);
582 else
583 bh = V2_minix_update_inode(inode);
584 if (!bh)
585 return -EIO;
586 if (wbc->sync_mode == WB_SYNC_ALL && buffer_dirty(bh)) {
587 sync_dirty_buffer(bh);
588 if (buffer_req(bh) && !buffer_uptodate(bh)) {
589 printk("IO error syncing minix inode [%s:%08lx]\n",
590 inode->i_sb->s_id, inode->i_ino);
591 err = -EIO;
592 }
593 }
594 brelse (bh);
595 return err;
596}
597
598int minix_getattr(struct vfsmount *mnt, struct dentry *dentry, struct kstat *stat)
599{
600 struct inode *dir = dentry->d_parent->d_inode;
601 struct super_block *sb = dir->i_sb;
602 generic_fillattr(dentry->d_inode, stat);
603 if (INODE_VERSION(dentry->d_inode) == MINIX_V1)
604 stat->blocks = (BLOCK_SIZE / 512) * V1_minix_blocks(stat->size, sb);
605 else
606 stat->blocks = (sb->s_blocksize / 512) * V2_minix_blocks(stat->size, sb);
607 stat->blksize = sb->s_blocksize;
608 return 0;
609}
610
611
612
613
614void minix_truncate(struct inode * inode)
615{
616 if (!(S_ISREG(inode->i_mode) || S_ISDIR(inode->i_mode) || S_ISLNK(inode->i_mode)))
617 return;
618 if (INODE_VERSION(inode) == MINIX_V1)
619 V1_minix_truncate(inode);
620 else
621 V2_minix_truncate(inode);
622}
623
624static struct dentry *minix_mount(struct file_system_type *fs_type,
625 int flags, const char *dev_name, void *data)
626{
627 return mount_bdev(fs_type, flags, dev_name, data, minix_fill_super);
628}
629
630static struct file_system_type minix_fs_type = {
631 .owner = THIS_MODULE,
632 .name = "minix",
633 .mount = minix_mount,
634 .kill_sb = kill_block_super,
635 .fs_flags = FS_REQUIRES_DEV,
636};
637
638static int __init init_minix_fs(void)
639{
640 int err = init_inodecache();
641 if (err)
642 goto out1;
643 err = register_filesystem(&minix_fs_type);
644 if (err)
645 goto out;
646 return 0;
647out:
648 destroy_inodecache();
649out1:
650 return err;
651}
652
653static void __exit exit_minix_fs(void)
654{
655 unregister_filesystem(&minix_fs_type);
656 destroy_inodecache();
657}
658
659module_init(init_minix_fs)
660module_exit(exit_minix_fs)
661MODULE_LICENSE("GPL");
662
663
