diff options
author | Linus Torvalds <torvalds@ppc970.osdl.org> | 2005-04-16 18:20:36 -0400 |
---|---|---|
committer | Linus Torvalds <torvalds@ppc970.osdl.org> | 2005-04-16 18:20:36 -0400 |
commit | 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 (patch) | |
tree | 0bba044c4ce775e45a88a51686b5d9f90697ea9d /fs/fat/inode.c |
Linux-2.6.12-rc2v2.6.12-rc2
Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.
Let it rip!
Diffstat (limited to 'fs/fat/inode.c')
-rw-r--r-- | fs/fat/inode.c | 1351 |
1 files changed, 1351 insertions, 0 deletions
diff --git a/fs/fat/inode.c b/fs/fat/inode.c new file mode 100644 index 000000000000..8ccee8415488 --- /dev/null +++ b/fs/fat/inode.c | |||
@@ -0,0 +1,1351 @@ | |||
1 | /* | ||
2 | * linux/fs/fat/inode.c | ||
3 | * | ||
4 | * Written 1992,1993 by Werner Almesberger | ||
5 | * VFAT extensions by Gordon Chaffee, merged with msdos fs by Henrik Storner | ||
6 | * Rewritten for the constant inumbers support by Al Viro | ||
7 | * | ||
8 | * Fixes: | ||
9 | * | ||
10 | * Max Cohan: Fixed invalid FSINFO offset when info_sector is 0 | ||
11 | */ | ||
12 | |||
13 | #include <linux/module.h> | ||
14 | #include <linux/init.h> | ||
15 | #include <linux/time.h> | ||
16 | #include <linux/slab.h> | ||
17 | #include <linux/smp_lock.h> | ||
18 | #include <linux/seq_file.h> | ||
19 | #include <linux/msdos_fs.h> | ||
20 | #include <linux/pagemap.h> | ||
21 | #include <linux/buffer_head.h> | ||
22 | #include <linux/mount.h> | ||
23 | #include <linux/vfs.h> | ||
24 | #include <linux/parser.h> | ||
25 | #include <asm/unaligned.h> | ||
26 | |||
27 | #ifndef CONFIG_FAT_DEFAULT_IOCHARSET | ||
28 | /* if user don't select VFAT, this is undefined. */ | ||
29 | #define CONFIG_FAT_DEFAULT_IOCHARSET "" | ||
30 | #endif | ||
31 | |||
32 | static int fat_default_codepage = CONFIG_FAT_DEFAULT_CODEPAGE; | ||
33 | static char fat_default_iocharset[] = CONFIG_FAT_DEFAULT_IOCHARSET; | ||
34 | |||
35 | |||
36 | static int fat_add_cluster(struct inode *inode) | ||
37 | { | ||
38 | int err, cluster; | ||
39 | |||
40 | err = fat_alloc_clusters(inode, &cluster, 1); | ||
41 | if (err) | ||
42 | return err; | ||
43 | /* FIXME: this cluster should be added after data of this | ||
44 | * cluster is writed */ | ||
45 | err = fat_chain_add(inode, cluster, 1); | ||
46 | if (err) | ||
47 | fat_free_clusters(inode, cluster); | ||
48 | return err; | ||
49 | } | ||
50 | |||
51 | static int fat_get_block(struct inode *inode, sector_t iblock, | ||
52 | struct buffer_head *bh_result, int create) | ||
53 | { | ||
54 | struct super_block *sb = inode->i_sb; | ||
55 | sector_t phys; | ||
56 | int err; | ||
57 | |||
58 | err = fat_bmap(inode, iblock, &phys); | ||
59 | if (err) | ||
60 | return err; | ||
61 | if (phys) { | ||
62 | map_bh(bh_result, sb, phys); | ||
63 | return 0; | ||
64 | } | ||
65 | if (!create) | ||
66 | return 0; | ||
67 | if (iblock != MSDOS_I(inode)->mmu_private >> sb->s_blocksize_bits) { | ||
68 | fat_fs_panic(sb, "corrupted file size (i_pos %lld, %lld)", | ||
69 | MSDOS_I(inode)->i_pos, MSDOS_I(inode)->mmu_private); | ||
70 | return -EIO; | ||
71 | } | ||
72 | if (!((unsigned long)iblock & (MSDOS_SB(sb)->sec_per_clus - 1))) { | ||
73 | err = fat_add_cluster(inode); | ||
74 | if (err) | ||
75 | return err; | ||
76 | } | ||
77 | MSDOS_I(inode)->mmu_private += sb->s_blocksize; | ||
78 | err = fat_bmap(inode, iblock, &phys); | ||
79 | if (err) | ||
80 | return err; | ||
81 | if (!phys) | ||
82 | BUG(); | ||
83 | set_buffer_new(bh_result); | ||
84 | map_bh(bh_result, sb, phys); | ||
85 | return 0; | ||
86 | } | ||
87 | |||
88 | static int fat_writepage(struct page *page, struct writeback_control *wbc) | ||
89 | { | ||
90 | return block_write_full_page(page, fat_get_block, wbc); | ||
91 | } | ||
92 | |||
93 | static int fat_readpage(struct file *file, struct page *page) | ||
94 | { | ||
95 | return block_read_full_page(page, fat_get_block); | ||
96 | } | ||
97 | |||
98 | static int fat_prepare_write(struct file *file, struct page *page, | ||
99 | unsigned from, unsigned to) | ||
100 | { | ||
101 | return cont_prepare_write(page, from, to, fat_get_block, | ||
102 | &MSDOS_I(page->mapping->host)->mmu_private); | ||
103 | } | ||
104 | |||
105 | static sector_t _fat_bmap(struct address_space *mapping, sector_t block) | ||
106 | { | ||
107 | return generic_block_bmap(mapping, block, fat_get_block); | ||
108 | } | ||
109 | |||
110 | static struct address_space_operations fat_aops = { | ||
111 | .readpage = fat_readpage, | ||
112 | .writepage = fat_writepage, | ||
113 | .sync_page = block_sync_page, | ||
114 | .prepare_write = fat_prepare_write, | ||
115 | .commit_write = generic_commit_write, | ||
116 | .bmap = _fat_bmap | ||
117 | }; | ||
118 | |||
119 | /* | ||
120 | * New FAT inode stuff. We do the following: | ||
121 | * a) i_ino is constant and has nothing with on-disk location. | ||
122 | * b) FAT manages its own cache of directory entries. | ||
123 | * c) *This* cache is indexed by on-disk location. | ||
124 | * d) inode has an associated directory entry, all right, but | ||
125 | * it may be unhashed. | ||
126 | * e) currently entries are stored within struct inode. That should | ||
127 | * change. | ||
128 | * f) we deal with races in the following way: | ||
129 | * 1. readdir() and lookup() do FAT-dir-cache lookup. | ||
130 | * 2. rename() unhashes the F-d-c entry and rehashes it in | ||
131 | * a new place. | ||
132 | * 3. unlink() and rmdir() unhash F-d-c entry. | ||
133 | * 4. fat_write_inode() checks whether the thing is unhashed. | ||
134 | * If it is we silently return. If it isn't we do bread(), | ||
135 | * check if the location is still valid and retry if it | ||
136 | * isn't. Otherwise we do changes. | ||
137 | * 5. Spinlock is used to protect hash/unhash/location check/lookup | ||
138 | * 6. fat_clear_inode() unhashes the F-d-c entry. | ||
139 | * 7. lookup() and readdir() do igrab() if they find a F-d-c entry | ||
140 | * and consider negative result as cache miss. | ||
141 | */ | ||
142 | |||
143 | static void fat_hash_init(struct super_block *sb) | ||
144 | { | ||
145 | struct msdos_sb_info *sbi = MSDOS_SB(sb); | ||
146 | int i; | ||
147 | |||
148 | spin_lock_init(&sbi->inode_hash_lock); | ||
149 | for (i = 0; i < FAT_HASH_SIZE; i++) | ||
150 | INIT_HLIST_HEAD(&sbi->inode_hashtable[i]); | ||
151 | } | ||
152 | |||
153 | static inline unsigned long fat_hash(struct super_block *sb, loff_t i_pos) | ||
154 | { | ||
155 | unsigned long tmp = (unsigned long)i_pos | (unsigned long) sb; | ||
156 | tmp = tmp + (tmp >> FAT_HASH_BITS) + (tmp >> FAT_HASH_BITS * 2); | ||
157 | return tmp & FAT_HASH_MASK; | ||
158 | } | ||
159 | |||
160 | void fat_attach(struct inode *inode, loff_t i_pos) | ||
161 | { | ||
162 | struct super_block *sb = inode->i_sb; | ||
163 | struct msdos_sb_info *sbi = MSDOS_SB(sb); | ||
164 | |||
165 | spin_lock(&sbi->inode_hash_lock); | ||
166 | MSDOS_I(inode)->i_pos = i_pos; | ||
167 | hlist_add_head(&MSDOS_I(inode)->i_fat_hash, | ||
168 | sbi->inode_hashtable + fat_hash(sb, i_pos)); | ||
169 | spin_unlock(&sbi->inode_hash_lock); | ||
170 | } | ||
171 | |||
172 | EXPORT_SYMBOL(fat_attach); | ||
173 | |||
174 | void fat_detach(struct inode *inode) | ||
175 | { | ||
176 | struct msdos_sb_info *sbi = MSDOS_SB(inode->i_sb); | ||
177 | spin_lock(&sbi->inode_hash_lock); | ||
178 | MSDOS_I(inode)->i_pos = 0; | ||
179 | hlist_del_init(&MSDOS_I(inode)->i_fat_hash); | ||
180 | spin_unlock(&sbi->inode_hash_lock); | ||
181 | } | ||
182 | |||
183 | EXPORT_SYMBOL(fat_detach); | ||
184 | |||
185 | struct inode *fat_iget(struct super_block *sb, loff_t i_pos) | ||
186 | { | ||
187 | struct msdos_sb_info *sbi = MSDOS_SB(sb); | ||
188 | struct hlist_head *head = sbi->inode_hashtable + fat_hash(sb, i_pos); | ||
189 | struct hlist_node *_p; | ||
190 | struct msdos_inode_info *i; | ||
191 | struct inode *inode = NULL; | ||
192 | |||
193 | spin_lock(&sbi->inode_hash_lock); | ||
194 | hlist_for_each_entry(i, _p, head, i_fat_hash) { | ||
195 | BUG_ON(i->vfs_inode.i_sb != sb); | ||
196 | if (i->i_pos != i_pos) | ||
197 | continue; | ||
198 | inode = igrab(&i->vfs_inode); | ||
199 | if (inode) | ||
200 | break; | ||
201 | } | ||
202 | spin_unlock(&sbi->inode_hash_lock); | ||
203 | return inode; | ||
204 | } | ||
205 | |||
206 | static int is_exec(unsigned char *extension) | ||
207 | { | ||
208 | unsigned char *exe_extensions = "EXECOMBAT", *walk; | ||
209 | |||
210 | for (walk = exe_extensions; *walk; walk += 3) | ||
211 | if (!strncmp(extension, walk, 3)) | ||
212 | return 1; | ||
213 | return 0; | ||
214 | } | ||
215 | |||
216 | static int fat_calc_dir_size(struct inode *inode) | ||
217 | { | ||
218 | struct msdos_sb_info *sbi = MSDOS_SB(inode->i_sb); | ||
219 | int ret, fclus, dclus; | ||
220 | |||
221 | inode->i_size = 0; | ||
222 | if (MSDOS_I(inode)->i_start == 0) | ||
223 | return 0; | ||
224 | |||
225 | ret = fat_get_cluster(inode, FAT_ENT_EOF, &fclus, &dclus); | ||
226 | if (ret < 0) | ||
227 | return ret; | ||
228 | inode->i_size = (fclus + 1) << sbi->cluster_bits; | ||
229 | |||
230 | return 0; | ||
231 | } | ||
232 | |||
233 | /* doesn't deal with root inode */ | ||
234 | static int fat_fill_inode(struct inode *inode, struct msdos_dir_entry *de) | ||
235 | { | ||
236 | struct msdos_sb_info *sbi = MSDOS_SB(inode->i_sb); | ||
237 | int error; | ||
238 | |||
239 | MSDOS_I(inode)->i_pos = 0; | ||
240 | inode->i_uid = sbi->options.fs_uid; | ||
241 | inode->i_gid = sbi->options.fs_gid; | ||
242 | inode->i_version++; | ||
243 | inode->i_generation = get_seconds(); | ||
244 | |||
245 | if ((de->attr & ATTR_DIR) && !IS_FREE(de->name)) { | ||
246 | inode->i_generation &= ~1; | ||
247 | inode->i_mode = MSDOS_MKMODE(de->attr, | ||
248 | S_IRWXUGO & ~sbi->options.fs_dmask) | S_IFDIR; | ||
249 | inode->i_op = sbi->dir_ops; | ||
250 | inode->i_fop = &fat_dir_operations; | ||
251 | |||
252 | MSDOS_I(inode)->i_start = le16_to_cpu(de->start); | ||
253 | if (sbi->fat_bits == 32) | ||
254 | MSDOS_I(inode)->i_start |= (le16_to_cpu(de->starthi) << 16); | ||
255 | |||
256 | MSDOS_I(inode)->i_logstart = MSDOS_I(inode)->i_start; | ||
257 | error = fat_calc_dir_size(inode); | ||
258 | if (error < 0) | ||
259 | return error; | ||
260 | MSDOS_I(inode)->mmu_private = inode->i_size; | ||
261 | |||
262 | inode->i_nlink = fat_subdirs(inode); | ||
263 | } else { /* not a directory */ | ||
264 | inode->i_generation |= 1; | ||
265 | inode->i_mode = MSDOS_MKMODE(de->attr, | ||
266 | ((sbi->options.showexec && | ||
267 | !is_exec(de->ext)) | ||
268 | ? S_IRUGO|S_IWUGO : S_IRWXUGO) | ||
269 | & ~sbi->options.fs_fmask) | S_IFREG; | ||
270 | MSDOS_I(inode)->i_start = le16_to_cpu(de->start); | ||
271 | if (sbi->fat_bits == 32) | ||
272 | MSDOS_I(inode)->i_start |= (le16_to_cpu(de->starthi) << 16); | ||
273 | |||
274 | MSDOS_I(inode)->i_logstart = MSDOS_I(inode)->i_start; | ||
275 | inode->i_size = le32_to_cpu(de->size); | ||
276 | inode->i_op = &fat_file_inode_operations; | ||
277 | inode->i_fop = &fat_file_operations; | ||
278 | inode->i_mapping->a_ops = &fat_aops; | ||
279 | MSDOS_I(inode)->mmu_private = inode->i_size; | ||
280 | } | ||
281 | if (de->attr & ATTR_SYS) { | ||
282 | if (sbi->options.sys_immutable) | ||
283 | inode->i_flags |= S_IMMUTABLE; | ||
284 | } | ||
285 | MSDOS_I(inode)->i_attrs = de->attr & ATTR_UNUSED; | ||
286 | /* this is as close to the truth as we can get ... */ | ||
287 | inode->i_blksize = sbi->cluster_size; | ||
288 | inode->i_blocks = ((inode->i_size + (sbi->cluster_size - 1)) | ||
289 | & ~((loff_t)sbi->cluster_size - 1)) >> 9; | ||
290 | inode->i_mtime.tv_sec = inode->i_atime.tv_sec = | ||
291 | date_dos2unix(le16_to_cpu(de->time), le16_to_cpu(de->date)); | ||
292 | inode->i_mtime.tv_nsec = inode->i_atime.tv_nsec = 0; | ||
293 | if (sbi->options.isvfat) { | ||
294 | int secs = de->ctime_cs / 100; | ||
295 | int csecs = de->ctime_cs % 100; | ||
296 | inode->i_ctime.tv_sec = | ||
297 | date_dos2unix(le16_to_cpu(de->ctime), | ||
298 | le16_to_cpu(de->cdate)) + secs; | ||
299 | inode->i_ctime.tv_nsec = csecs * 10000000; | ||
300 | } else | ||
301 | inode->i_ctime = inode->i_mtime; | ||
302 | |||
303 | return 0; | ||
304 | } | ||
305 | |||
306 | struct inode *fat_build_inode(struct super_block *sb, | ||
307 | struct msdos_dir_entry *de, loff_t i_pos) | ||
308 | { | ||
309 | struct inode *inode; | ||
310 | int err; | ||
311 | |||
312 | inode = fat_iget(sb, i_pos); | ||
313 | if (inode) | ||
314 | goto out; | ||
315 | inode = new_inode(sb); | ||
316 | if (!inode) { | ||
317 | inode = ERR_PTR(-ENOMEM); | ||
318 | goto out; | ||
319 | } | ||
320 | inode->i_ino = iunique(sb, MSDOS_ROOT_INO); | ||
321 | inode->i_version = 1; | ||
322 | err = fat_fill_inode(inode, de); | ||
323 | if (err) { | ||
324 | iput(inode); | ||
325 | inode = ERR_PTR(err); | ||
326 | goto out; | ||
327 | } | ||
328 | fat_attach(inode, i_pos); | ||
329 | insert_inode_hash(inode); | ||
330 | out: | ||
331 | return inode; | ||
332 | } | ||
333 | |||
334 | EXPORT_SYMBOL(fat_build_inode); | ||
335 | |||
336 | static void fat_delete_inode(struct inode *inode) | ||
337 | { | ||
338 | if (!is_bad_inode(inode)) { | ||
339 | inode->i_size = 0; | ||
340 | fat_truncate(inode); | ||
341 | } | ||
342 | clear_inode(inode); | ||
343 | } | ||
344 | |||
345 | static void fat_clear_inode(struct inode *inode) | ||
346 | { | ||
347 | struct msdos_sb_info *sbi = MSDOS_SB(inode->i_sb); | ||
348 | |||
349 | if (is_bad_inode(inode)) | ||
350 | return; | ||
351 | lock_kernel(); | ||
352 | spin_lock(&sbi->inode_hash_lock); | ||
353 | fat_cache_inval_inode(inode); | ||
354 | hlist_del_init(&MSDOS_I(inode)->i_fat_hash); | ||
355 | spin_unlock(&sbi->inode_hash_lock); | ||
356 | unlock_kernel(); | ||
357 | } | ||
358 | |||
359 | static void fat_put_super(struct super_block *sb) | ||
360 | { | ||
361 | struct msdos_sb_info *sbi = MSDOS_SB(sb); | ||
362 | |||
363 | if (!(sb->s_flags & MS_RDONLY)) | ||
364 | fat_clusters_flush(sb); | ||
365 | |||
366 | if (sbi->nls_disk) { | ||
367 | unload_nls(sbi->nls_disk); | ||
368 | sbi->nls_disk = NULL; | ||
369 | sbi->options.codepage = fat_default_codepage; | ||
370 | } | ||
371 | if (sbi->nls_io) { | ||
372 | unload_nls(sbi->nls_io); | ||
373 | sbi->nls_io = NULL; | ||
374 | } | ||
375 | if (sbi->options.iocharset != fat_default_iocharset) { | ||
376 | kfree(sbi->options.iocharset); | ||
377 | sbi->options.iocharset = fat_default_iocharset; | ||
378 | } | ||
379 | |||
380 | sb->s_fs_info = NULL; | ||
381 | kfree(sbi); | ||
382 | } | ||
383 | |||
384 | static kmem_cache_t *fat_inode_cachep; | ||
385 | |||
386 | static struct inode *fat_alloc_inode(struct super_block *sb) | ||
387 | { | ||
388 | struct msdos_inode_info *ei; | ||
389 | ei = kmem_cache_alloc(fat_inode_cachep, SLAB_KERNEL); | ||
390 | if (!ei) | ||
391 | return NULL; | ||
392 | return &ei->vfs_inode; | ||
393 | } | ||
394 | |||
395 | static void fat_destroy_inode(struct inode *inode) | ||
396 | { | ||
397 | kmem_cache_free(fat_inode_cachep, MSDOS_I(inode)); | ||
398 | } | ||
399 | |||
400 | static void init_once(void * foo, kmem_cache_t * cachep, unsigned long flags) | ||
401 | { | ||
402 | struct msdos_inode_info *ei = (struct msdos_inode_info *)foo; | ||
403 | |||
404 | if ((flags & (SLAB_CTOR_VERIFY|SLAB_CTOR_CONSTRUCTOR)) == | ||
405 | SLAB_CTOR_CONSTRUCTOR) { | ||
406 | spin_lock_init(&ei->cache_lru_lock); | ||
407 | ei->nr_caches = 0; | ||
408 | ei->cache_valid_id = FAT_CACHE_VALID + 1; | ||
409 | INIT_LIST_HEAD(&ei->cache_lru); | ||
410 | INIT_HLIST_NODE(&ei->i_fat_hash); | ||
411 | inode_init_once(&ei->vfs_inode); | ||
412 | } | ||
413 | } | ||
414 | |||
415 | static int __init fat_init_inodecache(void) | ||
416 | { | ||
417 | fat_inode_cachep = kmem_cache_create("fat_inode_cache", | ||
418 | sizeof(struct msdos_inode_info), | ||
419 | 0, SLAB_RECLAIM_ACCOUNT, | ||
420 | init_once, NULL); | ||
421 | if (fat_inode_cachep == NULL) | ||
422 | return -ENOMEM; | ||
423 | return 0; | ||
424 | } | ||
425 | |||
426 | static void __exit fat_destroy_inodecache(void) | ||
427 | { | ||
428 | if (kmem_cache_destroy(fat_inode_cachep)) | ||
429 | printk(KERN_INFO "fat_inode_cache: not all structures were freed\n"); | ||
430 | } | ||
431 | |||
432 | static int fat_remount(struct super_block *sb, int *flags, char *data) | ||
433 | { | ||
434 | struct msdos_sb_info *sbi = MSDOS_SB(sb); | ||
435 | *flags |= MS_NODIRATIME | (sbi->options.isvfat ? 0 : MS_NOATIME); | ||
436 | return 0; | ||
437 | } | ||
438 | |||
439 | static int fat_statfs(struct super_block *sb, struct kstatfs *buf) | ||
440 | { | ||
441 | struct msdos_sb_info *sbi = MSDOS_SB(sb); | ||
442 | |||
443 | /* If the count of free cluster is still unknown, counts it here. */ | ||
444 | if (sbi->free_clusters == -1) { | ||
445 | int err = fat_count_free_clusters(sb); | ||
446 | if (err) | ||
447 | return err; | ||
448 | } | ||
449 | |||
450 | buf->f_type = sb->s_magic; | ||
451 | buf->f_bsize = sbi->cluster_size; | ||
452 | buf->f_blocks = sbi->max_cluster - FAT_START_ENT; | ||
453 | buf->f_bfree = sbi->free_clusters; | ||
454 | buf->f_bavail = sbi->free_clusters; | ||
455 | buf->f_namelen = sbi->options.isvfat ? 260 : 12; | ||
456 | |||
457 | return 0; | ||
458 | } | ||
459 | |||
460 | static int fat_write_inode(struct inode *inode, int wait) | ||
461 | { | ||
462 | struct super_block *sb = inode->i_sb; | ||
463 | struct msdos_sb_info *sbi = MSDOS_SB(sb); | ||
464 | struct buffer_head *bh; | ||
465 | struct msdos_dir_entry *raw_entry; | ||
466 | loff_t i_pos; | ||
467 | int err = 0; | ||
468 | |||
469 | retry: | ||
470 | i_pos = MSDOS_I(inode)->i_pos; | ||
471 | if (inode->i_ino == MSDOS_ROOT_INO || !i_pos) | ||
472 | return 0; | ||
473 | |||
474 | lock_kernel(); | ||
475 | bh = sb_bread(sb, i_pos >> sbi->dir_per_block_bits); | ||
476 | if (!bh) { | ||
477 | printk(KERN_ERR "FAT: unable to read inode block " | ||
478 | "for updating (i_pos %lld)\n", i_pos); | ||
479 | err = -EIO; | ||
480 | goto out; | ||
481 | } | ||
482 | spin_lock(&sbi->inode_hash_lock); | ||
483 | if (i_pos != MSDOS_I(inode)->i_pos) { | ||
484 | spin_unlock(&sbi->inode_hash_lock); | ||
485 | brelse(bh); | ||
486 | unlock_kernel(); | ||
487 | goto retry; | ||
488 | } | ||
489 | |||
490 | raw_entry = &((struct msdos_dir_entry *) (bh->b_data)) | ||
491 | [i_pos & (sbi->dir_per_block - 1)]; | ||
492 | if (S_ISDIR(inode->i_mode)) | ||
493 | raw_entry->size = 0; | ||
494 | else | ||
495 | raw_entry->size = cpu_to_le32(inode->i_size); | ||
496 | raw_entry->attr = fat_attr(inode); | ||
497 | raw_entry->start = cpu_to_le16(MSDOS_I(inode)->i_logstart); | ||
498 | raw_entry->starthi = cpu_to_le16(MSDOS_I(inode)->i_logstart >> 16); | ||
499 | fat_date_unix2dos(inode->i_mtime.tv_sec, &raw_entry->time, &raw_entry->date); | ||
500 | if (sbi->options.isvfat) { | ||
501 | fat_date_unix2dos(inode->i_ctime.tv_sec,&raw_entry->ctime,&raw_entry->cdate); | ||
502 | raw_entry->ctime_cs = (inode->i_ctime.tv_sec & 1) * 100 + | ||
503 | inode->i_ctime.tv_nsec / 10000000; | ||
504 | } | ||
505 | spin_unlock(&sbi->inode_hash_lock); | ||
506 | mark_buffer_dirty(bh); | ||
507 | if (wait) | ||
508 | err = sync_dirty_buffer(bh); | ||
509 | brelse(bh); | ||
510 | out: | ||
511 | unlock_kernel(); | ||
512 | return err; | ||
513 | } | ||
514 | |||
515 | int fat_sync_inode(struct inode *inode) | ||
516 | { | ||
517 | return fat_write_inode(inode, 1); | ||
518 | } | ||
519 | |||
520 | EXPORT_SYMBOL(fat_sync_inode); | ||
521 | |||
522 | static int fat_show_options(struct seq_file *m, struct vfsmount *mnt); | ||
523 | static struct super_operations fat_sops = { | ||
524 | .alloc_inode = fat_alloc_inode, | ||
525 | .destroy_inode = fat_destroy_inode, | ||
526 | .write_inode = fat_write_inode, | ||
527 | .delete_inode = fat_delete_inode, | ||
528 | .put_super = fat_put_super, | ||
529 | .statfs = fat_statfs, | ||
530 | .clear_inode = fat_clear_inode, | ||
531 | .remount_fs = fat_remount, | ||
532 | |||
533 | .read_inode = make_bad_inode, | ||
534 | |||
535 | .show_options = fat_show_options, | ||
536 | }; | ||
537 | |||
538 | /* | ||
539 | * a FAT file handle with fhtype 3 is | ||
540 | * 0/ i_ino - for fast, reliable lookup if still in the cache | ||
541 | * 1/ i_generation - to see if i_ino is still valid | ||
542 | * bit 0 == 0 iff directory | ||
543 | * 2/ i_pos(8-39) - if ino has changed, but still in cache | ||
544 | * 3/ i_pos(4-7)|i_logstart - to semi-verify inode found at i_pos | ||
545 | * 4/ i_pos(0-3)|parent->i_logstart - maybe used to hunt for the file on disc | ||
546 | * | ||
547 | * Hack for NFSv2: Maximum FAT entry number is 28bits and maximum | ||
548 | * i_pos is 40bits (blocknr(32) + dir offset(8)), so two 4bits | ||
549 | * of i_logstart is used to store the directory entry offset. | ||
550 | */ | ||
551 | |||
552 | static struct dentry * | ||
553 | fat_decode_fh(struct super_block *sb, __u32 *fh, int len, int fhtype, | ||
554 | int (*acceptable)(void *context, struct dentry *de), | ||
555 | void *context) | ||
556 | { | ||
557 | if (fhtype != 3) | ||
558 | return ERR_PTR(-ESTALE); | ||
559 | if (len < 5) | ||
560 | return ERR_PTR(-ESTALE); | ||
561 | |||
562 | return sb->s_export_op->find_exported_dentry(sb, fh, NULL, acceptable, context); | ||
563 | } | ||
564 | |||
565 | static struct dentry *fat_get_dentry(struct super_block *sb, void *inump) | ||
566 | { | ||
567 | struct inode *inode = NULL; | ||
568 | struct dentry *result; | ||
569 | __u32 *fh = inump; | ||
570 | |||
571 | inode = iget(sb, fh[0]); | ||
572 | if (!inode || is_bad_inode(inode) || inode->i_generation != fh[1]) { | ||
573 | if (inode) | ||
574 | iput(inode); | ||
575 | inode = NULL; | ||
576 | } | ||
577 | if (!inode) { | ||
578 | loff_t i_pos; | ||
579 | int i_logstart = fh[3] & 0x0fffffff; | ||
580 | |||
581 | i_pos = (loff_t)fh[2] << 8; | ||
582 | i_pos |= ((fh[3] >> 24) & 0xf0) | (fh[4] >> 28); | ||
583 | |||
584 | /* try 2 - see if i_pos is in F-d-c | ||
585 | * require i_logstart to be the same | ||
586 | * Will fail if you truncate and then re-write | ||
587 | */ | ||
588 | |||
589 | inode = fat_iget(sb, i_pos); | ||
590 | if (inode && MSDOS_I(inode)->i_logstart != i_logstart) { | ||
591 | iput(inode); | ||
592 | inode = NULL; | ||
593 | } | ||
594 | } | ||
595 | if (!inode) { | ||
596 | /* For now, do nothing | ||
597 | * What we could do is: | ||
598 | * follow the file starting at fh[4], and record | ||
599 | * the ".." entry, and the name of the fh[2] entry. | ||
600 | * The follow the ".." file finding the next step up. | ||
601 | * This way we build a path to the root of | ||
602 | * the tree. If this works, we lookup the path and so | ||
603 | * get this inode into the cache. | ||
604 | * Finally try the fat_iget lookup again | ||
605 | * If that fails, then weare totally out of luck | ||
606 | * But all that is for another day | ||
607 | */ | ||
608 | } | ||
609 | if (!inode) | ||
610 | return ERR_PTR(-ESTALE); | ||
611 | |||
612 | |||
613 | /* now to find a dentry. | ||
614 | * If possible, get a well-connected one | ||
615 | */ | ||
616 | result = d_alloc_anon(inode); | ||
617 | if (result == NULL) { | ||
618 | iput(inode); | ||
619 | return ERR_PTR(-ENOMEM); | ||
620 | } | ||
621 | result->d_op = sb->s_root->d_op; | ||
622 | return result; | ||
623 | } | ||
624 | |||
625 | static int | ||
626 | fat_encode_fh(struct dentry *de, __u32 *fh, int *lenp, int connectable) | ||
627 | { | ||
628 | int len = *lenp; | ||
629 | struct inode *inode = de->d_inode; | ||
630 | u32 ipos_h, ipos_m, ipos_l; | ||
631 | |||
632 | if (len < 5) | ||
633 | return 255; /* no room */ | ||
634 | |||
635 | ipos_h = MSDOS_I(inode)->i_pos >> 8; | ||
636 | ipos_m = (MSDOS_I(inode)->i_pos & 0xf0) << 24; | ||
637 | ipos_l = (MSDOS_I(inode)->i_pos & 0x0f) << 28; | ||
638 | *lenp = 5; | ||
639 | fh[0] = inode->i_ino; | ||
640 | fh[1] = inode->i_generation; | ||
641 | fh[2] = ipos_h; | ||
642 | fh[3] = ipos_m | MSDOS_I(inode)->i_logstart; | ||
643 | spin_lock(&de->d_lock); | ||
644 | fh[4] = ipos_l | MSDOS_I(de->d_parent->d_inode)->i_logstart; | ||
645 | spin_unlock(&de->d_lock); | ||
646 | return 3; | ||
647 | } | ||
648 | |||
649 | static struct dentry *fat_get_parent(struct dentry *child) | ||
650 | { | ||
651 | struct buffer_head *bh; | ||
652 | struct msdos_dir_entry *de; | ||
653 | loff_t i_pos; | ||
654 | struct dentry *parent; | ||
655 | struct inode *inode; | ||
656 | int err; | ||
657 | |||
658 | lock_kernel(); | ||
659 | |||
660 | err = fat_get_dotdot_entry(child->d_inode, &bh, &de, &i_pos); | ||
661 | if (err) { | ||
662 | parent = ERR_PTR(err); | ||
663 | goto out; | ||
664 | } | ||
665 | inode = fat_build_inode(child->d_sb, de, i_pos); | ||
666 | brelse(bh); | ||
667 | if (IS_ERR(inode)) { | ||
668 | parent = ERR_PTR(PTR_ERR(inode)); | ||
669 | goto out; | ||
670 | } | ||
671 | parent = d_alloc_anon(inode); | ||
672 | if (!parent) { | ||
673 | iput(inode); | ||
674 | parent = ERR_PTR(-ENOMEM); | ||
675 | } | ||
676 | out: | ||
677 | unlock_kernel(); | ||
678 | |||
679 | return parent; | ||
680 | } | ||
681 | |||
682 | static struct export_operations fat_export_ops = { | ||
683 | .decode_fh = fat_decode_fh, | ||
684 | .encode_fh = fat_encode_fh, | ||
685 | .get_dentry = fat_get_dentry, | ||
686 | .get_parent = fat_get_parent, | ||
687 | }; | ||
688 | |||
689 | static int fat_show_options(struct seq_file *m, struct vfsmount *mnt) | ||
690 | { | ||
691 | struct msdos_sb_info *sbi = MSDOS_SB(mnt->mnt_sb); | ||
692 | struct fat_mount_options *opts = &sbi->options; | ||
693 | int isvfat = opts->isvfat; | ||
694 | |||
695 | if (opts->fs_uid != 0) | ||
696 | seq_printf(m, ",uid=%u", opts->fs_uid); | ||
697 | if (opts->fs_gid != 0) | ||
698 | seq_printf(m, ",gid=%u", opts->fs_gid); | ||
699 | seq_printf(m, ",fmask=%04o", opts->fs_fmask); | ||
700 | seq_printf(m, ",dmask=%04o", opts->fs_dmask); | ||
701 | if (sbi->nls_disk) | ||
702 | seq_printf(m, ",codepage=%s", sbi->nls_disk->charset); | ||
703 | if (isvfat) { | ||
704 | if (sbi->nls_io) | ||
705 | seq_printf(m, ",iocharset=%s", sbi->nls_io->charset); | ||
706 | |||
707 | switch (opts->shortname) { | ||
708 | case VFAT_SFN_DISPLAY_WIN95 | VFAT_SFN_CREATE_WIN95: | ||
709 | seq_puts(m, ",shortname=win95"); | ||
710 | break; | ||
711 | case VFAT_SFN_DISPLAY_WINNT | VFAT_SFN_CREATE_WINNT: | ||
712 | seq_puts(m, ",shortname=winnt"); | ||
713 | break; | ||
714 | case VFAT_SFN_DISPLAY_WINNT | VFAT_SFN_CREATE_WIN95: | ||
715 | seq_puts(m, ",shortname=mixed"); | ||
716 | break; | ||
717 | case VFAT_SFN_DISPLAY_LOWER | VFAT_SFN_CREATE_WIN95: | ||
718 | /* seq_puts(m, ",shortname=lower"); */ | ||
719 | break; | ||
720 | default: | ||
721 | seq_puts(m, ",shortname=unknown"); | ||
722 | break; | ||
723 | } | ||
724 | } | ||
725 | if (opts->name_check != 'n') | ||
726 | seq_printf(m, ",check=%c", opts->name_check); | ||
727 | if (opts->quiet) | ||
728 | seq_puts(m, ",quiet"); | ||
729 | if (opts->showexec) | ||
730 | seq_puts(m, ",showexec"); | ||
731 | if (opts->sys_immutable) | ||
732 | seq_puts(m, ",sys_immutable"); | ||
733 | if (!isvfat) { | ||
734 | if (opts->dotsOK) | ||
735 | seq_puts(m, ",dotsOK=yes"); | ||
736 | if (opts->nocase) | ||
737 | seq_puts(m, ",nocase"); | ||
738 | } else { | ||
739 | if (opts->utf8) | ||
740 | seq_puts(m, ",utf8"); | ||
741 | if (opts->unicode_xlate) | ||
742 | seq_puts(m, ",uni_xlate"); | ||
743 | if (!opts->numtail) | ||
744 | seq_puts(m, ",nonumtail"); | ||
745 | } | ||
746 | |||
747 | return 0; | ||
748 | } | ||
749 | |||
750 | enum { | ||
751 | Opt_check_n, Opt_check_r, Opt_check_s, Opt_uid, Opt_gid, | ||
752 | Opt_umask, Opt_dmask, Opt_fmask, Opt_codepage, Opt_nocase, | ||
753 | Opt_quiet, Opt_showexec, Opt_debug, Opt_immutable, | ||
754 | Opt_dots, Opt_nodots, | ||
755 | Opt_charset, Opt_shortname_lower, Opt_shortname_win95, | ||
756 | Opt_shortname_winnt, Opt_shortname_mixed, Opt_utf8_no, Opt_utf8_yes, | ||
757 | Opt_uni_xl_no, Opt_uni_xl_yes, Opt_nonumtail_no, Opt_nonumtail_yes, | ||
758 | Opt_obsolate, Opt_err, | ||
759 | }; | ||
760 | |||
761 | static match_table_t fat_tokens = { | ||
762 | {Opt_check_r, "check=relaxed"}, | ||
763 | {Opt_check_s, "check=strict"}, | ||
764 | {Opt_check_n, "check=normal"}, | ||
765 | {Opt_check_r, "check=r"}, | ||
766 | {Opt_check_s, "check=s"}, | ||
767 | {Opt_check_n, "check=n"}, | ||
768 | {Opt_uid, "uid=%u"}, | ||
769 | {Opt_gid, "gid=%u"}, | ||
770 | {Opt_umask, "umask=%o"}, | ||
771 | {Opt_dmask, "dmask=%o"}, | ||
772 | {Opt_fmask, "fmask=%o"}, | ||
773 | {Opt_codepage, "codepage=%u"}, | ||
774 | {Opt_nocase, "nocase"}, | ||
775 | {Opt_quiet, "quiet"}, | ||
776 | {Opt_showexec, "showexec"}, | ||
777 | {Opt_debug, "debug"}, | ||
778 | {Opt_immutable, "sys_immutable"}, | ||
779 | {Opt_obsolate, "conv=binary"}, | ||
780 | {Opt_obsolate, "conv=text"}, | ||
781 | {Opt_obsolate, "conv=auto"}, | ||
782 | {Opt_obsolate, "conv=b"}, | ||
783 | {Opt_obsolate, "conv=t"}, | ||
784 | {Opt_obsolate, "conv=a"}, | ||
785 | {Opt_obsolate, "fat=%u"}, | ||
786 | {Opt_obsolate, "blocksize=%u"}, | ||
787 | {Opt_obsolate, "cvf_format=%20s"}, | ||
788 | {Opt_obsolate, "cvf_options=%100s"}, | ||
789 | {Opt_obsolate, "posix"}, | ||
790 | {Opt_err, NULL} | ||
791 | }; | ||
792 | static match_table_t msdos_tokens = { | ||
793 | {Opt_nodots, "nodots"}, | ||
794 | {Opt_nodots, "dotsOK=no"}, | ||
795 | {Opt_dots, "dots"}, | ||
796 | {Opt_dots, "dotsOK=yes"}, | ||
797 | {Opt_err, NULL} | ||
798 | }; | ||
799 | static match_table_t vfat_tokens = { | ||
800 | {Opt_charset, "iocharset=%s"}, | ||
801 | {Opt_shortname_lower, "shortname=lower"}, | ||
802 | {Opt_shortname_win95, "shortname=win95"}, | ||
803 | {Opt_shortname_winnt, "shortname=winnt"}, | ||
804 | {Opt_shortname_mixed, "shortname=mixed"}, | ||
805 | {Opt_utf8_no, "utf8=0"}, /* 0 or no or false */ | ||
806 | {Opt_utf8_no, "utf8=no"}, | ||
807 | {Opt_utf8_no, "utf8=false"}, | ||
808 | {Opt_utf8_yes, "utf8=1"}, /* empty or 1 or yes or true */ | ||
809 | {Opt_utf8_yes, "utf8=yes"}, | ||
810 | {Opt_utf8_yes, "utf8=true"}, | ||
811 | {Opt_utf8_yes, "utf8"}, | ||
812 | {Opt_uni_xl_no, "uni_xlate=0"}, /* 0 or no or false */ | ||
813 | {Opt_uni_xl_no, "uni_xlate=no"}, | ||
814 | {Opt_uni_xl_no, "uni_xlate=false"}, | ||
815 | {Opt_uni_xl_yes, "uni_xlate=1"}, /* empty or 1 or yes or true */ | ||
816 | {Opt_uni_xl_yes, "uni_xlate=yes"}, | ||
817 | {Opt_uni_xl_yes, "uni_xlate=true"}, | ||
818 | {Opt_uni_xl_yes, "uni_xlate"}, | ||
819 | {Opt_nonumtail_no, "nonumtail=0"}, /* 0 or no or false */ | ||
820 | {Opt_nonumtail_no, "nonumtail=no"}, | ||
821 | {Opt_nonumtail_no, "nonumtail=false"}, | ||
822 | {Opt_nonumtail_yes, "nonumtail=1"}, /* empty or 1 or yes or true */ | ||
823 | {Opt_nonumtail_yes, "nonumtail=yes"}, | ||
824 | {Opt_nonumtail_yes, "nonumtail=true"}, | ||
825 | {Opt_nonumtail_yes, "nonumtail"}, | ||
826 | {Opt_err, NULL} | ||
827 | }; | ||
828 | |||
829 | static int parse_options(char *options, int is_vfat, int *debug, | ||
830 | struct fat_mount_options *opts) | ||
831 | { | ||
832 | char *p; | ||
833 | substring_t args[MAX_OPT_ARGS]; | ||
834 | int option; | ||
835 | char *iocharset; | ||
836 | |||
837 | opts->isvfat = is_vfat; | ||
838 | |||
839 | opts->fs_uid = current->uid; | ||
840 | opts->fs_gid = current->gid; | ||
841 | opts->fs_fmask = opts->fs_dmask = current->fs->umask; | ||
842 | opts->codepage = fat_default_codepage; | ||
843 | opts->iocharset = fat_default_iocharset; | ||
844 | if (is_vfat) | ||
845 | opts->shortname = VFAT_SFN_DISPLAY_LOWER|VFAT_SFN_CREATE_WIN95; | ||
846 | else | ||
847 | opts->shortname = 0; | ||
848 | opts->name_check = 'n'; | ||
849 | opts->quiet = opts->showexec = opts->sys_immutable = opts->dotsOK = 0; | ||
850 | opts->utf8 = opts->unicode_xlate = 0; | ||
851 | opts->numtail = 1; | ||
852 | opts->nocase = 0; | ||
853 | *debug = 0; | ||
854 | |||
855 | if (!options) | ||
856 | return 0; | ||
857 | |||
858 | while ((p = strsep(&options, ",")) != NULL) { | ||
859 | int token; | ||
860 | if (!*p) | ||
861 | continue; | ||
862 | |||
863 | token = match_token(p, fat_tokens, args); | ||
864 | if (token == Opt_err) { | ||
865 | if (is_vfat) | ||
866 | token = match_token(p, vfat_tokens, args); | ||
867 | else | ||
868 | token = match_token(p, msdos_tokens, args); | ||
869 | } | ||
870 | switch (token) { | ||
871 | case Opt_check_s: | ||
872 | opts->name_check = 's'; | ||
873 | break; | ||
874 | case Opt_check_r: | ||
875 | opts->name_check = 'r'; | ||
876 | break; | ||
877 | case Opt_check_n: | ||
878 | opts->name_check = 'n'; | ||
879 | break; | ||
880 | case Opt_nocase: | ||
881 | if (!is_vfat) | ||
882 | opts->nocase = 1; | ||
883 | else { | ||
884 | /* for backward compatibility */ | ||
885 | opts->shortname = VFAT_SFN_DISPLAY_WIN95 | ||
886 | | VFAT_SFN_CREATE_WIN95; | ||
887 | } | ||
888 | break; | ||
889 | case Opt_quiet: | ||
890 | opts->quiet = 1; | ||
891 | break; | ||
892 | case Opt_showexec: | ||
893 | opts->showexec = 1; | ||
894 | break; | ||
895 | case Opt_debug: | ||
896 | *debug = 1; | ||
897 | break; | ||
898 | case Opt_immutable: | ||
899 | opts->sys_immutable = 1; | ||
900 | break; | ||
901 | case Opt_uid: | ||
902 | if (match_int(&args[0], &option)) | ||
903 | return 0; | ||
904 | opts->fs_uid = option; | ||
905 | break; | ||
906 | case Opt_gid: | ||
907 | if (match_int(&args[0], &option)) | ||
908 | return 0; | ||
909 | opts->fs_gid = option; | ||
910 | break; | ||
911 | case Opt_umask: | ||
912 | if (match_octal(&args[0], &option)) | ||
913 | return 0; | ||
914 | opts->fs_fmask = opts->fs_dmask = option; | ||
915 | break; | ||
916 | case Opt_dmask: | ||
917 | if (match_octal(&args[0], &option)) | ||
918 | return 0; | ||
919 | opts->fs_dmask = option; | ||
920 | break; | ||
921 | case Opt_fmask: | ||
922 | if (match_octal(&args[0], &option)) | ||
923 | return 0; | ||
924 | opts->fs_fmask = option; | ||
925 | break; | ||
926 | case Opt_codepage: | ||
927 | if (match_int(&args[0], &option)) | ||
928 | return 0; | ||
929 | opts->codepage = option; | ||
930 | break; | ||
931 | |||
932 | /* msdos specific */ | ||
933 | case Opt_dots: | ||
934 | opts->dotsOK = 1; | ||
935 | break; | ||
936 | case Opt_nodots: | ||
937 | opts->dotsOK = 0; | ||
938 | break; | ||
939 | |||
940 | /* vfat specific */ | ||
941 | case Opt_charset: | ||
942 | if (opts->iocharset != fat_default_iocharset) | ||
943 | kfree(opts->iocharset); | ||
944 | iocharset = match_strdup(&args[0]); | ||
945 | if (!iocharset) | ||
946 | return -ENOMEM; | ||
947 | opts->iocharset = iocharset; | ||
948 | break; | ||
949 | case Opt_shortname_lower: | ||
950 | opts->shortname = VFAT_SFN_DISPLAY_LOWER | ||
951 | | VFAT_SFN_CREATE_WIN95; | ||
952 | break; | ||
953 | case Opt_shortname_win95: | ||
954 | opts->shortname = VFAT_SFN_DISPLAY_WIN95 | ||
955 | | VFAT_SFN_CREATE_WIN95; | ||
956 | break; | ||
957 | case Opt_shortname_winnt: | ||
958 | opts->shortname = VFAT_SFN_DISPLAY_WINNT | ||
959 | | VFAT_SFN_CREATE_WINNT; | ||
960 | break; | ||
961 | case Opt_shortname_mixed: | ||
962 | opts->shortname = VFAT_SFN_DISPLAY_WINNT | ||
963 | | VFAT_SFN_CREATE_WIN95; | ||
964 | break; | ||
965 | case Opt_utf8_no: /* 0 or no or false */ | ||
966 | opts->utf8 = 0; | ||
967 | break; | ||
968 | case Opt_utf8_yes: /* empty or 1 or yes or true */ | ||
969 | opts->utf8 = 1; | ||
970 | break; | ||
971 | case Opt_uni_xl_no: /* 0 or no or false */ | ||
972 | opts->unicode_xlate = 0; | ||
973 | break; | ||
974 | case Opt_uni_xl_yes: /* empty or 1 or yes or true */ | ||
975 | opts->unicode_xlate = 1; | ||
976 | break; | ||
977 | case Opt_nonumtail_no: /* 0 or no or false */ | ||
978 | opts->numtail = 1; /* negated option */ | ||
979 | break; | ||
980 | case Opt_nonumtail_yes: /* empty or 1 or yes or true */ | ||
981 | opts->numtail = 0; /* negated option */ | ||
982 | break; | ||
983 | |||
984 | /* obsolete mount options */ | ||
985 | case Opt_obsolate: | ||
986 | printk(KERN_INFO "FAT: \"%s\" option is obsolete, " | ||
987 | "not supported now\n", p); | ||
988 | break; | ||
989 | /* unknown option */ | ||
990 | default: | ||
991 | printk(KERN_ERR "FAT: Unrecognized mount option \"%s\" " | ||
992 | "or missing value\n", p); | ||
993 | return -EINVAL; | ||
994 | } | ||
995 | } | ||
996 | /* UTF8 doesn't provide FAT semantics */ | ||
997 | if (!strcmp(opts->iocharset, "utf8")) { | ||
998 | printk(KERN_ERR "FAT: utf8 is not a recommended IO charset" | ||
999 | " for FAT filesystems, filesystem will be case sensitive!\n"); | ||
1000 | } | ||
1001 | |||
1002 | if (opts->unicode_xlate) | ||
1003 | opts->utf8 = 0; | ||
1004 | |||
1005 | return 0; | ||
1006 | } | ||
1007 | |||
1008 | static int fat_read_root(struct inode *inode) | ||
1009 | { | ||
1010 | struct super_block *sb = inode->i_sb; | ||
1011 | struct msdos_sb_info *sbi = MSDOS_SB(sb); | ||
1012 | int error; | ||
1013 | |||
1014 | MSDOS_I(inode)->i_pos = 0; | ||
1015 | inode->i_uid = sbi->options.fs_uid; | ||
1016 | inode->i_gid = sbi->options.fs_gid; | ||
1017 | inode->i_version++; | ||
1018 | inode->i_generation = 0; | ||
1019 | inode->i_mode = (S_IRWXUGO & ~sbi->options.fs_dmask) | S_IFDIR; | ||
1020 | inode->i_op = sbi->dir_ops; | ||
1021 | inode->i_fop = &fat_dir_operations; | ||
1022 | if (sbi->fat_bits == 32) { | ||
1023 | MSDOS_I(inode)->i_start = sbi->root_cluster; | ||
1024 | error = fat_calc_dir_size(inode); | ||
1025 | if (error < 0) | ||
1026 | return error; | ||
1027 | } else { | ||
1028 | MSDOS_I(inode)->i_start = 0; | ||
1029 | inode->i_size = sbi->dir_entries * sizeof(struct msdos_dir_entry); | ||
1030 | } | ||
1031 | inode->i_blksize = sbi->cluster_size; | ||
1032 | inode->i_blocks = ((inode->i_size + (sbi->cluster_size - 1)) | ||
1033 | & ~((loff_t)sbi->cluster_size - 1)) >> 9; | ||
1034 | MSDOS_I(inode)->i_logstart = 0; | ||
1035 | MSDOS_I(inode)->mmu_private = inode->i_size; | ||
1036 | |||
1037 | MSDOS_I(inode)->i_attrs = ATTR_NONE; | ||
1038 | inode->i_mtime.tv_sec = inode->i_atime.tv_sec = inode->i_ctime.tv_sec = 0; | ||
1039 | inode->i_mtime.tv_nsec = inode->i_atime.tv_nsec = inode->i_ctime.tv_nsec = 0; | ||
1040 | inode->i_nlink = fat_subdirs(inode)+2; | ||
1041 | |||
1042 | return 0; | ||
1043 | } | ||
1044 | |||
1045 | /* | ||
1046 | * Read the super block of an MS-DOS FS. | ||
1047 | */ | ||
1048 | int fat_fill_super(struct super_block *sb, void *data, int silent, | ||
1049 | struct inode_operations *fs_dir_inode_ops, int isvfat) | ||
1050 | { | ||
1051 | struct inode *root_inode = NULL; | ||
1052 | struct buffer_head *bh; | ||
1053 | struct fat_boot_sector *b; | ||
1054 | struct msdos_sb_info *sbi; | ||
1055 | u16 logical_sector_size; | ||
1056 | u32 total_sectors, total_clusters, fat_clusters, rootdir_sectors; | ||
1057 | int debug; | ||
1058 | unsigned int media; | ||
1059 | long error; | ||
1060 | char buf[50]; | ||
1061 | |||
1062 | sbi = kmalloc(sizeof(struct msdos_sb_info), GFP_KERNEL); | ||
1063 | if (!sbi) | ||
1064 | return -ENOMEM; | ||
1065 | sb->s_fs_info = sbi; | ||
1066 | memset(sbi, 0, sizeof(struct msdos_sb_info)); | ||
1067 | |||
1068 | sb->s_flags |= MS_NODIRATIME; | ||
1069 | sb->s_magic = MSDOS_SUPER_MAGIC; | ||
1070 | sb->s_op = &fat_sops; | ||
1071 | sb->s_export_op = &fat_export_ops; | ||
1072 | sbi->dir_ops = fs_dir_inode_ops; | ||
1073 | |||
1074 | error = parse_options(data, isvfat, &debug, &sbi->options); | ||
1075 | if (error) | ||
1076 | goto out_fail; | ||
1077 | |||
1078 | error = -EIO; | ||
1079 | sb_min_blocksize(sb, 512); | ||
1080 | bh = sb_bread(sb, 0); | ||
1081 | if (bh == NULL) { | ||
1082 | printk(KERN_ERR "FAT: unable to read boot sector\n"); | ||
1083 | goto out_fail; | ||
1084 | } | ||
1085 | |||
1086 | b = (struct fat_boot_sector *) bh->b_data; | ||
1087 | if (!b->reserved) { | ||
1088 | if (!silent) | ||
1089 | printk(KERN_ERR "FAT: bogus number of reserved sectors\n"); | ||
1090 | brelse(bh); | ||
1091 | goto out_invalid; | ||
1092 | } | ||
1093 | if (!b->fats) { | ||
1094 | if (!silent) | ||
1095 | printk(KERN_ERR "FAT: bogus number of FAT structure\n"); | ||
1096 | brelse(bh); | ||
1097 | goto out_invalid; | ||
1098 | } | ||
1099 | |||
1100 | /* | ||
1101 | * Earlier we checked here that b->secs_track and b->head are nonzero, | ||
1102 | * but it turns out valid FAT filesystems can have zero there. | ||
1103 | */ | ||
1104 | |||
1105 | media = b->media; | ||
1106 | if (!FAT_VALID_MEDIA(media)) { | ||
1107 | if (!silent) | ||
1108 | printk(KERN_ERR "FAT: invalid media value (0x%02x)\n", | ||
1109 | media); | ||
1110 | brelse(bh); | ||
1111 | goto out_invalid; | ||
1112 | } | ||
1113 | logical_sector_size = | ||
1114 | le16_to_cpu(get_unaligned((__le16 *)&b->sector_size)); | ||
1115 | if (!logical_sector_size | ||
1116 | || (logical_sector_size & (logical_sector_size - 1)) | ||
1117 | || (logical_sector_size < 512) | ||
1118 | || (PAGE_CACHE_SIZE < logical_sector_size)) { | ||
1119 | if (!silent) | ||
1120 | printk(KERN_ERR "FAT: bogus logical sector size %u\n", | ||
1121 | logical_sector_size); | ||
1122 | brelse(bh); | ||
1123 | goto out_invalid; | ||
1124 | } | ||
1125 | sbi->sec_per_clus = b->sec_per_clus; | ||
1126 | if (!sbi->sec_per_clus | ||
1127 | || (sbi->sec_per_clus & (sbi->sec_per_clus - 1))) { | ||
1128 | if (!silent) | ||
1129 | printk(KERN_ERR "FAT: bogus sectors per cluster %u\n", | ||
1130 | sbi->sec_per_clus); | ||
1131 | brelse(bh); | ||
1132 | goto out_invalid; | ||
1133 | } | ||
1134 | |||
1135 | if (logical_sector_size < sb->s_blocksize) { | ||
1136 | printk(KERN_ERR "FAT: logical sector size too small for device" | ||
1137 | " (logical sector size = %u)\n", logical_sector_size); | ||
1138 | brelse(bh); | ||
1139 | goto out_fail; | ||
1140 | } | ||
1141 | if (logical_sector_size > sb->s_blocksize) { | ||
1142 | brelse(bh); | ||
1143 | |||
1144 | if (!sb_set_blocksize(sb, logical_sector_size)) { | ||
1145 | printk(KERN_ERR "FAT: unable to set blocksize %u\n", | ||
1146 | logical_sector_size); | ||
1147 | goto out_fail; | ||
1148 | } | ||
1149 | bh = sb_bread(sb, 0); | ||
1150 | if (bh == NULL) { | ||
1151 | printk(KERN_ERR "FAT: unable to read boot sector" | ||
1152 | " (logical sector size = %lu)\n", | ||
1153 | sb->s_blocksize); | ||
1154 | goto out_fail; | ||
1155 | } | ||
1156 | b = (struct fat_boot_sector *) bh->b_data; | ||
1157 | } | ||
1158 | |||
1159 | sbi->cluster_size = sb->s_blocksize * sbi->sec_per_clus; | ||
1160 | sbi->cluster_bits = ffs(sbi->cluster_size) - 1; | ||
1161 | sbi->fats = b->fats; | ||
1162 | sbi->fat_bits = 0; /* Don't know yet */ | ||
1163 | sbi->fat_start = le16_to_cpu(b->reserved); | ||
1164 | sbi->fat_length = le16_to_cpu(b->fat_length); | ||
1165 | sbi->root_cluster = 0; | ||
1166 | sbi->free_clusters = -1; /* Don't know yet */ | ||
1167 | sbi->prev_free = FAT_START_ENT; | ||
1168 | |||
1169 | if (!sbi->fat_length && b->fat32_length) { | ||
1170 | struct fat_boot_fsinfo *fsinfo; | ||
1171 | struct buffer_head *fsinfo_bh; | ||
1172 | |||
1173 | /* Must be FAT32 */ | ||
1174 | sbi->fat_bits = 32; | ||
1175 | sbi->fat_length = le32_to_cpu(b->fat32_length); | ||
1176 | sbi->root_cluster = le32_to_cpu(b->root_cluster); | ||
1177 | |||
1178 | sb->s_maxbytes = 0xffffffff; | ||
1179 | |||
1180 | /* MC - if info_sector is 0, don't multiply by 0 */ | ||
1181 | sbi->fsinfo_sector = le16_to_cpu(b->info_sector); | ||
1182 | if (sbi->fsinfo_sector == 0) | ||
1183 | sbi->fsinfo_sector = 1; | ||
1184 | |||
1185 | fsinfo_bh = sb_bread(sb, sbi->fsinfo_sector); | ||
1186 | if (fsinfo_bh == NULL) { | ||
1187 | printk(KERN_ERR "FAT: bread failed, FSINFO block" | ||
1188 | " (sector = %lu)\n", sbi->fsinfo_sector); | ||
1189 | brelse(bh); | ||
1190 | goto out_fail; | ||
1191 | } | ||
1192 | |||
1193 | fsinfo = (struct fat_boot_fsinfo *)fsinfo_bh->b_data; | ||
1194 | if (!IS_FSINFO(fsinfo)) { | ||
1195 | printk(KERN_WARNING | ||
1196 | "FAT: Did not find valid FSINFO signature.\n" | ||
1197 | " Found signature1 0x%08x signature2 0x%08x" | ||
1198 | " (sector = %lu)\n", | ||
1199 | le32_to_cpu(fsinfo->signature1), | ||
1200 | le32_to_cpu(fsinfo->signature2), | ||
1201 | sbi->fsinfo_sector); | ||
1202 | } else { | ||
1203 | sbi->free_clusters = le32_to_cpu(fsinfo->free_clusters); | ||
1204 | sbi->prev_free = le32_to_cpu(fsinfo->next_cluster); | ||
1205 | } | ||
1206 | |||
1207 | brelse(fsinfo_bh); | ||
1208 | } | ||
1209 | |||
1210 | sbi->dir_per_block = sb->s_blocksize / sizeof(struct msdos_dir_entry); | ||
1211 | sbi->dir_per_block_bits = ffs(sbi->dir_per_block) - 1; | ||
1212 | |||
1213 | sbi->dir_start = sbi->fat_start + sbi->fats * sbi->fat_length; | ||
1214 | sbi->dir_entries = | ||
1215 | le16_to_cpu(get_unaligned((__le16 *)&b->dir_entries)); | ||
1216 | if (sbi->dir_entries & (sbi->dir_per_block - 1)) { | ||
1217 | if (!silent) | ||
1218 | printk(KERN_ERR "FAT: bogus directroy-entries per block" | ||
1219 | " (%u)\n", sbi->dir_entries); | ||
1220 | brelse(bh); | ||
1221 | goto out_invalid; | ||
1222 | } | ||
1223 | |||
1224 | rootdir_sectors = sbi->dir_entries | ||
1225 | * sizeof(struct msdos_dir_entry) / sb->s_blocksize; | ||
1226 | sbi->data_start = sbi->dir_start + rootdir_sectors; | ||
1227 | total_sectors = le16_to_cpu(get_unaligned((__le16 *)&b->sectors)); | ||
1228 | if (total_sectors == 0) | ||
1229 | total_sectors = le32_to_cpu(b->total_sect); | ||
1230 | |||
1231 | total_clusters = (total_sectors - sbi->data_start) / sbi->sec_per_clus; | ||
1232 | |||
1233 | if (sbi->fat_bits != 32) | ||
1234 | sbi->fat_bits = (total_clusters > MAX_FAT12) ? 16 : 12; | ||
1235 | |||
1236 | /* check that FAT table does not overflow */ | ||
1237 | fat_clusters = sbi->fat_length * sb->s_blocksize * 8 / sbi->fat_bits; | ||
1238 | total_clusters = min(total_clusters, fat_clusters - FAT_START_ENT); | ||
1239 | if (total_clusters > MAX_FAT(sb)) { | ||
1240 | if (!silent) | ||
1241 | printk(KERN_ERR "FAT: count of clusters too big (%u)\n", | ||
1242 | total_clusters); | ||
1243 | brelse(bh); | ||
1244 | goto out_invalid; | ||
1245 | } | ||
1246 | |||
1247 | sbi->max_cluster = total_clusters + FAT_START_ENT; | ||
1248 | /* check the free_clusters, it's not necessarily correct */ | ||
1249 | if (sbi->free_clusters != -1 && sbi->free_clusters > total_clusters) | ||
1250 | sbi->free_clusters = -1; | ||
1251 | /* check the prev_free, it's not necessarily correct */ | ||
1252 | sbi->prev_free %= sbi->max_cluster; | ||
1253 | if (sbi->prev_free < FAT_START_ENT) | ||
1254 | sbi->prev_free = FAT_START_ENT; | ||
1255 | |||
1256 | brelse(bh); | ||
1257 | |||
1258 | /* set up enough so that it can read an inode */ | ||
1259 | fat_hash_init(sb); | ||
1260 | fat_ent_access_init(sb); | ||
1261 | |||
1262 | /* | ||
1263 | * The low byte of FAT's first entry must have same value with | ||
1264 | * media-field. But in real world, too many devices is | ||
1265 | * writing wrong value. So, removed that validity check. | ||
1266 | * | ||
1267 | * if (FAT_FIRST_ENT(sb, media) != first) | ||
1268 | */ | ||
1269 | |||
1270 | error = -EINVAL; | ||
1271 | sprintf(buf, "cp%d", sbi->options.codepage); | ||
1272 | sbi->nls_disk = load_nls(buf); | ||
1273 | if (!sbi->nls_disk) { | ||
1274 | printk(KERN_ERR "FAT: codepage %s not found\n", buf); | ||
1275 | goto out_fail; | ||
1276 | } | ||
1277 | |||
1278 | /* FIXME: utf8 is using iocharset for upper/lower conversion */ | ||
1279 | if (sbi->options.isvfat) { | ||
1280 | sbi->nls_io = load_nls(sbi->options.iocharset); | ||
1281 | if (!sbi->nls_io) { | ||
1282 | printk(KERN_ERR "FAT: IO charset %s not found\n", | ||
1283 | sbi->options.iocharset); | ||
1284 | goto out_fail; | ||
1285 | } | ||
1286 | } | ||
1287 | |||
1288 | error = -ENOMEM; | ||
1289 | root_inode = new_inode(sb); | ||
1290 | if (!root_inode) | ||
1291 | goto out_fail; | ||
1292 | root_inode->i_ino = MSDOS_ROOT_INO; | ||
1293 | root_inode->i_version = 1; | ||
1294 | error = fat_read_root(root_inode); | ||
1295 | if (error < 0) | ||
1296 | goto out_fail; | ||
1297 | error = -ENOMEM; | ||
1298 | insert_inode_hash(root_inode); | ||
1299 | sb->s_root = d_alloc_root(root_inode); | ||
1300 | if (!sb->s_root) { | ||
1301 | printk(KERN_ERR "FAT: get root inode failed\n"); | ||
1302 | goto out_fail; | ||
1303 | } | ||
1304 | |||
1305 | return 0; | ||
1306 | |||
1307 | out_invalid: | ||
1308 | error = -EINVAL; | ||
1309 | if (!silent) | ||
1310 | printk(KERN_INFO "VFS: Can't find a valid FAT filesystem" | ||
1311 | " on dev %s.\n", sb->s_id); | ||
1312 | |||
1313 | out_fail: | ||
1314 | if (root_inode) | ||
1315 | iput(root_inode); | ||
1316 | if (sbi->nls_io) | ||
1317 | unload_nls(sbi->nls_io); | ||
1318 | if (sbi->nls_disk) | ||
1319 | unload_nls(sbi->nls_disk); | ||
1320 | if (sbi->options.iocharset != fat_default_iocharset) | ||
1321 | kfree(sbi->options.iocharset); | ||
1322 | sb->s_fs_info = NULL; | ||
1323 | kfree(sbi); | ||
1324 | return error; | ||
1325 | } | ||
1326 | |||
1327 | EXPORT_SYMBOL(fat_fill_super); | ||
1328 | |||
1329 | int __init fat_cache_init(void); | ||
1330 | void __exit fat_cache_destroy(void); | ||
1331 | |||
1332 | static int __init init_fat_fs(void) | ||
1333 | { | ||
1334 | int ret; | ||
1335 | |||
1336 | ret = fat_cache_init(); | ||
1337 | if (ret < 0) | ||
1338 | return ret; | ||
1339 | return fat_init_inodecache(); | ||
1340 | } | ||
1341 | |||
1342 | static void __exit exit_fat_fs(void) | ||
1343 | { | ||
1344 | fat_cache_destroy(); | ||
1345 | fat_destroy_inodecache(); | ||
1346 | } | ||
1347 | |||
1348 | module_init(init_fat_fs) | ||
1349 | module_exit(exit_fat_fs) | ||
1350 | |||
1351 | MODULE_LICENSE("GPL"); | ||