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
10 * Max Cohan: Fixed invalid FSINFO offset when info_sector is 0
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>
27 #ifndef CONFIG_FAT_DEFAULT_IOCHARSET
28 /* if user don't select VFAT, this is undefined. */
29 #define CONFIG_FAT_DEFAULT_IOCHARSET ""
32 static int fat_default_codepage
= CONFIG_FAT_DEFAULT_CODEPAGE
;
33 static char fat_default_iocharset
[] = CONFIG_FAT_DEFAULT_IOCHARSET
;
36 static int fat_add_cluster(struct inode
*inode
)
40 err
= fat_alloc_clusters(inode
, &cluster
, 1);
43 /* FIXME: this cluster should be added after data of this
44 * cluster is writed */
45 err
= fat_chain_add(inode
, cluster
, 1);
47 fat_free_clusters(inode
, cluster
);
51 static int fat_get_block(struct inode
*inode
, sector_t iblock
,
52 struct buffer_head
*bh_result
, int create
)
54 struct super_block
*sb
= inode
->i_sb
;
58 err
= fat_bmap(inode
, iblock
, &phys
);
62 map_bh(bh_result
, sb
, phys
);
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
);
72 if (!((unsigned long)iblock
& (MSDOS_SB(sb
)->sec_per_clus
- 1))) {
73 err
= fat_add_cluster(inode
);
77 MSDOS_I(inode
)->mmu_private
+= sb
->s_blocksize
;
78 err
= fat_bmap(inode
, iblock
, &phys
);
83 set_buffer_new(bh_result
);
84 map_bh(bh_result
, sb
, phys
);
88 static int fat_writepage(struct page
*page
, struct writeback_control
*wbc
)
90 return block_write_full_page(page
, fat_get_block
, wbc
);
93 static int fat_readpage(struct file
*file
, struct page
*page
)
95 return block_read_full_page(page
, fat_get_block
);
98 static int fat_prepare_write(struct file
*file
, struct page
*page
,
99 unsigned from
, unsigned to
)
101 return cont_prepare_write(page
, from
, to
, fat_get_block
,
102 &MSDOS_I(page
->mapping
->host
)->mmu_private
);
105 static sector_t
_fat_bmap(struct address_space
*mapping
, sector_t block
)
107 return generic_block_bmap(mapping
, block
, fat_get_block
);
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
,
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
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
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.
143 static void fat_hash_init(struct super_block
*sb
)
145 struct msdos_sb_info
*sbi
= MSDOS_SB(sb
);
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
]);
153 static inline unsigned long fat_hash(struct super_block
*sb
, loff_t i_pos
)
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
;
160 void fat_attach(struct inode
*inode
, loff_t i_pos
)
162 struct super_block
*sb
= inode
->i_sb
;
163 struct msdos_sb_info
*sbi
= MSDOS_SB(sb
);
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
);
172 EXPORT_SYMBOL(fat_attach
);
174 void fat_detach(struct inode
*inode
)
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
);
183 EXPORT_SYMBOL(fat_detach
);
185 struct inode
*fat_iget(struct super_block
*sb
, loff_t i_pos
)
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
;
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
)
198 inode
= igrab(&i
->vfs_inode
);
202 spin_unlock(&sbi
->inode_hash_lock
);
206 static int is_exec(unsigned char *extension
)
208 unsigned char *exe_extensions
= "EXECOMBAT", *walk
;
210 for (walk
= exe_extensions
; *walk
; walk
+= 3)
211 if (!strncmp(extension
, walk
, 3))
216 static int fat_calc_dir_size(struct inode
*inode
)
218 struct msdos_sb_info
*sbi
= MSDOS_SB(inode
->i_sb
);
219 int ret
, fclus
, dclus
;
222 if (MSDOS_I(inode
)->i_start
== 0)
225 ret
= fat_get_cluster(inode
, FAT_ENT_EOF
, &fclus
, &dclus
);
228 inode
->i_size
= (fclus
+ 1) << sbi
->cluster_bits
;
233 /* doesn't deal with root inode */
234 static int fat_fill_inode(struct inode
*inode
, struct msdos_dir_entry
*de
)
236 struct msdos_sb_info
*sbi
= MSDOS_SB(inode
->i_sb
);
239 MSDOS_I(inode
)->i_pos
= 0;
240 inode
->i_uid
= sbi
->options
.fs_uid
;
241 inode
->i_gid
= sbi
->options
.fs_gid
;
243 inode
->i_generation
= get_seconds();
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
;
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);
256 MSDOS_I(inode
)->i_logstart
= MSDOS_I(inode
)->i_start
;
257 error
= fat_calc_dir_size(inode
);
260 MSDOS_I(inode
)->mmu_private
= inode
->i_size
;
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
&&
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);
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
;
281 if (de
->attr
& ATTR_SYS
) {
282 if (sbi
->options
.sys_immutable
)
283 inode
->i_flags
|= S_IMMUTABLE
;
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;
301 inode
->i_ctime
= inode
->i_mtime
;
306 struct inode
*fat_build_inode(struct super_block
*sb
,
307 struct msdos_dir_entry
*de
, loff_t i_pos
)
312 inode
= fat_iget(sb
, i_pos
);
315 inode
= new_inode(sb
);
317 inode
= ERR_PTR(-ENOMEM
);
320 inode
->i_ino
= iunique(sb
, MSDOS_ROOT_INO
);
321 inode
->i_version
= 1;
322 err
= fat_fill_inode(inode
, de
);
325 inode
= ERR_PTR(err
);
328 fat_attach(inode
, i_pos
);
329 insert_inode_hash(inode
);
334 EXPORT_SYMBOL(fat_build_inode
);
336 static void fat_delete_inode(struct inode
*inode
)
338 if (!is_bad_inode(inode
)) {
345 static void fat_clear_inode(struct inode
*inode
)
347 struct msdos_sb_info
*sbi
= MSDOS_SB(inode
->i_sb
);
349 if (is_bad_inode(inode
))
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
);
359 static void fat_put_super(struct super_block
*sb
)
361 struct msdos_sb_info
*sbi
= MSDOS_SB(sb
);
363 if (!(sb
->s_flags
& MS_RDONLY
))
364 fat_clusters_flush(sb
);
367 unload_nls(sbi
->nls_disk
);
368 sbi
->nls_disk
= NULL
;
369 sbi
->options
.codepage
= fat_default_codepage
;
372 unload_nls(sbi
->nls_io
);
375 if (sbi
->options
.iocharset
!= fat_default_iocharset
) {
376 kfree(sbi
->options
.iocharset
);
377 sbi
->options
.iocharset
= fat_default_iocharset
;
380 sb
->s_fs_info
= NULL
;
384 static kmem_cache_t
*fat_inode_cachep
;
386 static struct inode
*fat_alloc_inode(struct super_block
*sb
)
388 struct msdos_inode_info
*ei
;
389 ei
= kmem_cache_alloc(fat_inode_cachep
, SLAB_KERNEL
);
392 return &ei
->vfs_inode
;
395 static void fat_destroy_inode(struct inode
*inode
)
397 kmem_cache_free(fat_inode_cachep
, MSDOS_I(inode
));
400 static void init_once(void * foo
, kmem_cache_t
* cachep
, unsigned long flags
)
402 struct msdos_inode_info
*ei
= (struct msdos_inode_info
*)foo
;
404 if ((flags
& (SLAB_CTOR_VERIFY
|SLAB_CTOR_CONSTRUCTOR
)) ==
405 SLAB_CTOR_CONSTRUCTOR
) {
406 spin_lock_init(&ei
->cache_lru_lock
);
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
);
415 static int __init
fat_init_inodecache(void)
417 fat_inode_cachep
= kmem_cache_create("fat_inode_cache",
418 sizeof(struct msdos_inode_info
),
419 0, SLAB_RECLAIM_ACCOUNT
,
421 if (fat_inode_cachep
== NULL
)
426 static void __exit
fat_destroy_inodecache(void)
428 if (kmem_cache_destroy(fat_inode_cachep
))
429 printk(KERN_INFO
"fat_inode_cache: not all structures were freed\n");
432 static int fat_remount(struct super_block
*sb
, int *flags
, char *data
)
434 struct msdos_sb_info
*sbi
= MSDOS_SB(sb
);
435 *flags
|= MS_NODIRATIME
| (sbi
->options
.isvfat
? 0 : MS_NOATIME
);
439 static int fat_statfs(struct super_block
*sb
, struct kstatfs
*buf
)
441 struct msdos_sb_info
*sbi
= MSDOS_SB(sb
);
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
);
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;
460 static int fat_write_inode(struct inode
*inode
, int wait
)
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
;
470 i_pos
= MSDOS_I(inode
)->i_pos
;
471 if (inode
->i_ino
== MSDOS_ROOT_INO
|| !i_pos
)
475 bh
= sb_bread(sb
, i_pos
>> sbi
->dir_per_block_bits
);
477 printk(KERN_ERR
"FAT: unable to read inode block "
478 "for updating (i_pos %lld)\n", i_pos
);
482 spin_lock(&sbi
->inode_hash_lock
);
483 if (i_pos
!= MSDOS_I(inode
)->i_pos
) {
484 spin_unlock(&sbi
->inode_hash_lock
);
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
))
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;
505 spin_unlock(&sbi
->inode_hash_lock
);
506 mark_buffer_dirty(bh
);
508 err
= sync_dirty_buffer(bh
);
515 int fat_sync_inode(struct inode
*inode
)
517 return fat_write_inode(inode
, 1);
520 EXPORT_SYMBOL(fat_sync_inode
);
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
,
533 .read_inode
= make_bad_inode
,
535 .show_options
= fat_show_options
,
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
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.
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
),
558 return ERR_PTR(-ESTALE
);
560 return ERR_PTR(-ESTALE
);
562 return sb
->s_export_op
->find_exported_dentry(sb
, fh
, NULL
, acceptable
, context
);
565 static struct dentry
*fat_get_dentry(struct super_block
*sb
, void *inump
)
567 struct inode
*inode
= NULL
;
568 struct dentry
*result
;
571 inode
= iget(sb
, fh
[0]);
572 if (!inode
|| is_bad_inode(inode
) || inode
->i_generation
!= fh
[1]) {
579 int i_logstart
= fh
[3] & 0x0fffffff;
581 i_pos
= (loff_t
)fh
[2] << 8;
582 i_pos
|= ((fh
[3] >> 24) & 0xf0) | (fh
[4] >> 28);
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
589 inode
= fat_iget(sb
, i_pos
);
590 if (inode
&& MSDOS_I(inode
)->i_logstart
!= i_logstart
) {
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
610 return ERR_PTR(-ESTALE
);
613 /* now to find a dentry.
614 * If possible, get a well-connected one
616 result
= d_alloc_anon(inode
);
617 if (result
== NULL
) {
619 return ERR_PTR(-ENOMEM
);
621 result
->d_op
= sb
->s_root
->d_op
;
626 fat_encode_fh(struct dentry
*de
, __u32
*fh
, int *lenp
, int connectable
)
629 struct inode
*inode
= de
->d_inode
;
630 u32 ipos_h
, ipos_m
, ipos_l
;
633 return 255; /* no room */
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;
639 fh
[0] = inode
->i_ino
;
640 fh
[1] = inode
->i_generation
;
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
);
649 static struct dentry
*fat_get_parent(struct dentry
*child
)
651 struct buffer_head
*bh
;
652 struct msdos_dir_entry
*de
;
654 struct dentry
*parent
;
660 err
= fat_get_dotdot_entry(child
->d_inode
, &bh
, &de
, &i_pos
);
662 parent
= ERR_PTR(err
);
665 inode
= fat_build_inode(child
->d_sb
, de
, i_pos
);
668 parent
= ERR_PTR(PTR_ERR(inode
));
671 parent
= d_alloc_anon(inode
);
674 parent
= ERR_PTR(-ENOMEM
);
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
,
689 static int fat_show_options(struct seq_file
*m
, struct vfsmount
*mnt
)
691 struct msdos_sb_info
*sbi
= MSDOS_SB(mnt
->mnt_sb
);
692 struct fat_mount_options
*opts
= &sbi
->options
;
693 int isvfat
= opts
->isvfat
;
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
);
702 seq_printf(m
, ",codepage=%s", sbi
->nls_disk
->charset
);
705 seq_printf(m
, ",iocharset=%s", sbi
->nls_io
->charset
);
707 switch (opts
->shortname
) {
708 case VFAT_SFN_DISPLAY_WIN95
| VFAT_SFN_CREATE_WIN95
:
709 seq_puts(m
, ",shortname=win95");
711 case VFAT_SFN_DISPLAY_WINNT
| VFAT_SFN_CREATE_WINNT
:
712 seq_puts(m
, ",shortname=winnt");
714 case VFAT_SFN_DISPLAY_WINNT
| VFAT_SFN_CREATE_WIN95
:
715 seq_puts(m
, ",shortname=mixed");
717 case VFAT_SFN_DISPLAY_LOWER
| VFAT_SFN_CREATE_WIN95
:
718 /* seq_puts(m, ",shortname=lower"); */
721 seq_puts(m
, ",shortname=unknown");
725 if (opts
->name_check
!= 'n')
726 seq_printf(m
, ",check=%c", opts
->name_check
);
728 seq_puts(m
, ",quiet");
730 seq_puts(m
, ",showexec");
731 if (opts
->sys_immutable
)
732 seq_puts(m
, ",sys_immutable");
735 seq_puts(m
, ",dotsOK=yes");
737 seq_puts(m
, ",nocase");
740 seq_puts(m
, ",utf8");
741 if (opts
->unicode_xlate
)
742 seq_puts(m
, ",uni_xlate");
744 seq_puts(m
, ",nonumtail");
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
,
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"},
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"},
792 static match_table_t msdos_tokens
= {
793 {Opt_nodots
, "nodots"},
794 {Opt_nodots
, "dotsOK=no"},
796 {Opt_dots
, "dotsOK=yes"},
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"},
829 static int parse_options(char *options
, int is_vfat
, int *debug
,
830 struct fat_mount_options
*opts
)
833 substring_t args
[MAX_OPT_ARGS
];
837 opts
->isvfat
= is_vfat
;
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
;
845 opts
->shortname
= VFAT_SFN_DISPLAY_LOWER
|VFAT_SFN_CREATE_WIN95
;
848 opts
->name_check
= 'n';
849 opts
->quiet
= opts
->showexec
= opts
->sys_immutable
= opts
->dotsOK
= 0;
850 opts
->utf8
= opts
->unicode_xlate
= 0;
858 while ((p
= strsep(&options
, ",")) != NULL
) {
863 token
= match_token(p
, fat_tokens
, args
);
864 if (token
== Opt_err
) {
866 token
= match_token(p
, vfat_tokens
, args
);
868 token
= match_token(p
, msdos_tokens
, args
);
872 opts
->name_check
= 's';
875 opts
->name_check
= 'r';
878 opts
->name_check
= 'n';
884 /* for backward compatibility */
885 opts
->shortname
= VFAT_SFN_DISPLAY_WIN95
886 | VFAT_SFN_CREATE_WIN95
;
899 opts
->sys_immutable
= 1;
902 if (match_int(&args
[0], &option
))
904 opts
->fs_uid
= option
;
907 if (match_int(&args
[0], &option
))
909 opts
->fs_gid
= option
;
912 if (match_octal(&args
[0], &option
))
914 opts
->fs_fmask
= opts
->fs_dmask
= option
;
917 if (match_octal(&args
[0], &option
))
919 opts
->fs_dmask
= option
;
922 if (match_octal(&args
[0], &option
))
924 opts
->fs_fmask
= option
;
927 if (match_int(&args
[0], &option
))
929 opts
->codepage
= option
;
942 if (opts
->iocharset
!= fat_default_iocharset
)
943 kfree(opts
->iocharset
);
944 iocharset
= match_strdup(&args
[0]);
947 opts
->iocharset
= iocharset
;
949 case Opt_shortname_lower
:
950 opts
->shortname
= VFAT_SFN_DISPLAY_LOWER
951 | VFAT_SFN_CREATE_WIN95
;
953 case Opt_shortname_win95
:
954 opts
->shortname
= VFAT_SFN_DISPLAY_WIN95
955 | VFAT_SFN_CREATE_WIN95
;
957 case Opt_shortname_winnt
:
958 opts
->shortname
= VFAT_SFN_DISPLAY_WINNT
959 | VFAT_SFN_CREATE_WINNT
;
961 case Opt_shortname_mixed
:
962 opts
->shortname
= VFAT_SFN_DISPLAY_WINNT
963 | VFAT_SFN_CREATE_WIN95
;
965 case Opt_utf8_no
: /* 0 or no or false */
968 case Opt_utf8_yes
: /* empty or 1 or yes or true */
971 case Opt_uni_xl_no
: /* 0 or no or false */
972 opts
->unicode_xlate
= 0;
974 case Opt_uni_xl_yes
: /* empty or 1 or yes or true */
975 opts
->unicode_xlate
= 1;
977 case Opt_nonumtail_no
: /* 0 or no or false */
978 opts
->numtail
= 1; /* negated option */
980 case Opt_nonumtail_yes
: /* empty or 1 or yes or true */
981 opts
->numtail
= 0; /* negated option */
984 /* obsolete mount options */
986 printk(KERN_INFO
"FAT: \"%s\" option is obsolete, "
987 "not supported now\n", p
);
991 printk(KERN_ERR
"FAT: Unrecognized mount option \"%s\" "
992 "or missing value\n", p
);
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");
1002 if (opts
->unicode_xlate
)
1008 static int fat_read_root(struct inode
*inode
)
1010 struct super_block
*sb
= inode
->i_sb
;
1011 struct msdos_sb_info
*sbi
= MSDOS_SB(sb
);
1014 MSDOS_I(inode
)->i_pos
= 0;
1015 inode
->i_uid
= sbi
->options
.fs_uid
;
1016 inode
->i_gid
= sbi
->options
.fs_gid
;
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
);
1028 MSDOS_I(inode
)->i_start
= 0;
1029 inode
->i_size
= sbi
->dir_entries
* sizeof(struct msdos_dir_entry
);
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
;
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;
1046 * Read the super block of an MS-DOS FS.
1048 int fat_fill_super(struct super_block
*sb
, void *data
, int silent
,
1049 struct inode_operations
*fs_dir_inode_ops
, int isvfat
)
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
;
1062 sbi
= kmalloc(sizeof(struct msdos_sb_info
), GFP_KERNEL
);
1065 sb
->s_fs_info
= sbi
;
1066 memset(sbi
, 0, sizeof(struct msdos_sb_info
));
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
;
1074 error
= parse_options(data
, isvfat
, &debug
, &sbi
->options
);
1079 sb_min_blocksize(sb
, 512);
1080 bh
= sb_bread(sb
, 0);
1082 printk(KERN_ERR
"FAT: unable to read boot sector\n");
1086 b
= (struct fat_boot_sector
*) bh
->b_data
;
1089 printk(KERN_ERR
"FAT: bogus number of reserved sectors\n");
1095 printk(KERN_ERR
"FAT: bogus number of FAT structure\n");
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.
1106 if (!FAT_VALID_MEDIA(media
)) {
1108 printk(KERN_ERR
"FAT: invalid media value (0x%02x)\n",
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
)) {
1120 printk(KERN_ERR
"FAT: bogus logical sector size %u\n",
1121 logical_sector_size
);
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))) {
1129 printk(KERN_ERR
"FAT: bogus sectors per cluster %u\n",
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
);
1141 if (logical_sector_size
> sb
->s_blocksize
) {
1144 if (!sb_set_blocksize(sb
, logical_sector_size
)) {
1145 printk(KERN_ERR
"FAT: unable to set blocksize %u\n",
1146 logical_sector_size
);
1149 bh
= sb_bread(sb
, 0);
1151 printk(KERN_ERR
"FAT: unable to read boot sector"
1152 " (logical sector size = %lu)\n",
1156 b
= (struct fat_boot_sector
*) bh
->b_data
;
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
;
1169 if (!sbi
->fat_length
&& b
->fat32_length
) {
1170 struct fat_boot_fsinfo
*fsinfo
;
1171 struct buffer_head
*fsinfo_bh
;
1175 sbi
->fat_length
= le32_to_cpu(b
->fat32_length
);
1176 sbi
->root_cluster
= le32_to_cpu(b
->root_cluster
);
1178 sb
->s_maxbytes
= 0xffffffff;
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;
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
);
1193 fsinfo
= (struct fat_boot_fsinfo
*)fsinfo_bh
->b_data
;
1194 if (!IS_FSINFO(fsinfo
)) {
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
);
1203 sbi
->free_clusters
= le32_to_cpu(fsinfo
->free_clusters
);
1204 sbi
->prev_free
= le32_to_cpu(fsinfo
->next_cluster
);
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;
1213 sbi
->dir_start
= sbi
->fat_start
+ sbi
->fats
* sbi
->fat_length
;
1215 le16_to_cpu(get_unaligned((__le16
*)&b
->dir_entries
));
1216 if (sbi
->dir_entries
& (sbi
->dir_per_block
- 1)) {
1218 printk(KERN_ERR
"FAT: bogus directroy-entries per block"
1219 " (%u)\n", sbi
->dir_entries
);
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
);
1231 total_clusters
= (total_sectors
- sbi
->data_start
) / sbi
->sec_per_clus
;
1233 if (sbi
->fat_bits
!= 32)
1234 sbi
->fat_bits
= (total_clusters
> MAX_FAT12
) ? 16 : 12;
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
)) {
1241 printk(KERN_ERR
"FAT: count of clusters too big (%u)\n",
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
;
1258 /* set up enough so that it can read an inode */
1260 fat_ent_access_init(sb
);
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.
1267 * if (FAT_FIRST_ENT(sb, media) != first)
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
);
1278 /* FIXME: utf8 is using iocharset for upper/lower conversion */
1279 if (sbi
->options
.isvfat
) {
1280 sbi
->nls_io
= load_nls(sbi
->options
.iocharset
);
1282 printk(KERN_ERR
"FAT: IO charset %s not found\n",
1283 sbi
->options
.iocharset
);
1289 root_inode
= new_inode(sb
);
1292 root_inode
->i_ino
= MSDOS_ROOT_INO
;
1293 root_inode
->i_version
= 1;
1294 error
= fat_read_root(root_inode
);
1298 insert_inode_hash(root_inode
);
1299 sb
->s_root
= d_alloc_root(root_inode
);
1301 printk(KERN_ERR
"FAT: get root inode failed\n");
1310 printk(KERN_INFO
"VFS: Can't find a valid FAT filesystem"
1311 " on dev %s.\n", sb
->s_id
);
1317 unload_nls(sbi
->nls_io
);
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
;
1327 EXPORT_SYMBOL(fat_fill_super
);
1329 int __init
fat_cache_init(void);
1330 void fat_cache_destroy(void);
1332 static int __init
init_fat_fs(void)
1336 err
= fat_cache_init();
1340 err
= fat_init_inodecache();
1347 fat_cache_destroy();
1351 static void __exit
exit_fat_fs(void)
1353 fat_cache_destroy();
1354 fat_destroy_inodecache();
1357 module_init(init_fat_fs
)
1358 module_exit(exit_fat_fs
)
1360 MODULE_LICENSE("GPL");