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 truncate_inode_pages(&inode
->i_data
, 0);
340 if (!is_bad_inode(inode
)) {
347 static void fat_clear_inode(struct inode
*inode
)
349 struct msdos_sb_info
*sbi
= MSDOS_SB(inode
->i_sb
);
351 if (is_bad_inode(inode
))
354 spin_lock(&sbi
->inode_hash_lock
);
355 fat_cache_inval_inode(inode
);
356 hlist_del_init(&MSDOS_I(inode
)->i_fat_hash
);
357 spin_unlock(&sbi
->inode_hash_lock
);
361 static void fat_put_super(struct super_block
*sb
)
363 struct msdos_sb_info
*sbi
= MSDOS_SB(sb
);
365 if (!(sb
->s_flags
& MS_RDONLY
))
366 fat_clusters_flush(sb
);
369 unload_nls(sbi
->nls_disk
);
370 sbi
->nls_disk
= NULL
;
371 sbi
->options
.codepage
= fat_default_codepage
;
374 unload_nls(sbi
->nls_io
);
377 if (sbi
->options
.iocharset
!= fat_default_iocharset
) {
378 kfree(sbi
->options
.iocharset
);
379 sbi
->options
.iocharset
= fat_default_iocharset
;
382 sb
->s_fs_info
= NULL
;
386 static kmem_cache_t
*fat_inode_cachep
;
388 static struct inode
*fat_alloc_inode(struct super_block
*sb
)
390 struct msdos_inode_info
*ei
;
391 ei
= kmem_cache_alloc(fat_inode_cachep
, SLAB_KERNEL
);
394 return &ei
->vfs_inode
;
397 static void fat_destroy_inode(struct inode
*inode
)
399 kmem_cache_free(fat_inode_cachep
, MSDOS_I(inode
));
402 static void init_once(void * foo
, kmem_cache_t
* cachep
, unsigned long flags
)
404 struct msdos_inode_info
*ei
= (struct msdos_inode_info
*)foo
;
406 if ((flags
& (SLAB_CTOR_VERIFY
|SLAB_CTOR_CONSTRUCTOR
)) ==
407 SLAB_CTOR_CONSTRUCTOR
) {
408 spin_lock_init(&ei
->cache_lru_lock
);
410 ei
->cache_valid_id
= FAT_CACHE_VALID
+ 1;
411 INIT_LIST_HEAD(&ei
->cache_lru
);
412 INIT_HLIST_NODE(&ei
->i_fat_hash
);
413 inode_init_once(&ei
->vfs_inode
);
417 static int __init
fat_init_inodecache(void)
419 fat_inode_cachep
= kmem_cache_create("fat_inode_cache",
420 sizeof(struct msdos_inode_info
),
421 0, SLAB_RECLAIM_ACCOUNT
,
423 if (fat_inode_cachep
== NULL
)
428 static void __exit
fat_destroy_inodecache(void)
430 if (kmem_cache_destroy(fat_inode_cachep
))
431 printk(KERN_INFO
"fat_inode_cache: not all structures were freed\n");
434 static int fat_remount(struct super_block
*sb
, int *flags
, char *data
)
436 struct msdos_sb_info
*sbi
= MSDOS_SB(sb
);
437 *flags
|= MS_NODIRATIME
| (sbi
->options
.isvfat
? 0 : MS_NOATIME
);
441 static int fat_statfs(struct super_block
*sb
, struct kstatfs
*buf
)
443 struct msdos_sb_info
*sbi
= MSDOS_SB(sb
);
445 /* If the count of free cluster is still unknown, counts it here. */
446 if (sbi
->free_clusters
== -1) {
447 int err
= fat_count_free_clusters(sb
);
452 buf
->f_type
= sb
->s_magic
;
453 buf
->f_bsize
= sbi
->cluster_size
;
454 buf
->f_blocks
= sbi
->max_cluster
- FAT_START_ENT
;
455 buf
->f_bfree
= sbi
->free_clusters
;
456 buf
->f_bavail
= sbi
->free_clusters
;
457 buf
->f_namelen
= sbi
->options
.isvfat
? 260 : 12;
462 static int fat_write_inode(struct inode
*inode
, int wait
)
464 struct super_block
*sb
= inode
->i_sb
;
465 struct msdos_sb_info
*sbi
= MSDOS_SB(sb
);
466 struct buffer_head
*bh
;
467 struct msdos_dir_entry
*raw_entry
;
472 i_pos
= MSDOS_I(inode
)->i_pos
;
473 if (inode
->i_ino
== MSDOS_ROOT_INO
|| !i_pos
)
477 bh
= sb_bread(sb
, i_pos
>> sbi
->dir_per_block_bits
);
479 printk(KERN_ERR
"FAT: unable to read inode block "
480 "for updating (i_pos %lld)\n", i_pos
);
484 spin_lock(&sbi
->inode_hash_lock
);
485 if (i_pos
!= MSDOS_I(inode
)->i_pos
) {
486 spin_unlock(&sbi
->inode_hash_lock
);
492 raw_entry
= &((struct msdos_dir_entry
*) (bh
->b_data
))
493 [i_pos
& (sbi
->dir_per_block
- 1)];
494 if (S_ISDIR(inode
->i_mode
))
497 raw_entry
->size
= cpu_to_le32(inode
->i_size
);
498 raw_entry
->attr
= fat_attr(inode
);
499 raw_entry
->start
= cpu_to_le16(MSDOS_I(inode
)->i_logstart
);
500 raw_entry
->starthi
= cpu_to_le16(MSDOS_I(inode
)->i_logstart
>> 16);
501 fat_date_unix2dos(inode
->i_mtime
.tv_sec
, &raw_entry
->time
, &raw_entry
->date
);
502 if (sbi
->options
.isvfat
) {
503 fat_date_unix2dos(inode
->i_ctime
.tv_sec
,&raw_entry
->ctime
,&raw_entry
->cdate
);
504 raw_entry
->ctime_cs
= (inode
->i_ctime
.tv_sec
& 1) * 100 +
505 inode
->i_ctime
.tv_nsec
/ 10000000;
507 spin_unlock(&sbi
->inode_hash_lock
);
508 mark_buffer_dirty(bh
);
510 err
= sync_dirty_buffer(bh
);
517 int fat_sync_inode(struct inode
*inode
)
519 return fat_write_inode(inode
, 1);
522 EXPORT_SYMBOL(fat_sync_inode
);
524 static int fat_show_options(struct seq_file
*m
, struct vfsmount
*mnt
);
525 static struct super_operations fat_sops
= {
526 .alloc_inode
= fat_alloc_inode
,
527 .destroy_inode
= fat_destroy_inode
,
528 .write_inode
= fat_write_inode
,
529 .delete_inode
= fat_delete_inode
,
530 .put_super
= fat_put_super
,
531 .statfs
= fat_statfs
,
532 .clear_inode
= fat_clear_inode
,
533 .remount_fs
= fat_remount
,
535 .read_inode
= make_bad_inode
,
537 .show_options
= fat_show_options
,
541 * a FAT file handle with fhtype 3 is
542 * 0/ i_ino - for fast, reliable lookup if still in the cache
543 * 1/ i_generation - to see if i_ino is still valid
544 * bit 0 == 0 iff directory
545 * 2/ i_pos(8-39) - if ino has changed, but still in cache
546 * 3/ i_pos(4-7)|i_logstart - to semi-verify inode found at i_pos
547 * 4/ i_pos(0-3)|parent->i_logstart - maybe used to hunt for the file on disc
549 * Hack for NFSv2: Maximum FAT entry number is 28bits and maximum
550 * i_pos is 40bits (blocknr(32) + dir offset(8)), so two 4bits
551 * of i_logstart is used to store the directory entry offset.
554 static struct dentry
*
555 fat_decode_fh(struct super_block
*sb
, __u32
*fh
, int len
, int fhtype
,
556 int (*acceptable
)(void *context
, struct dentry
*de
),
560 return ERR_PTR(-ESTALE
);
562 return ERR_PTR(-ESTALE
);
564 return sb
->s_export_op
->find_exported_dentry(sb
, fh
, NULL
, acceptable
, context
);
567 static struct dentry
*fat_get_dentry(struct super_block
*sb
, void *inump
)
569 struct inode
*inode
= NULL
;
570 struct dentry
*result
;
573 inode
= iget(sb
, fh
[0]);
574 if (!inode
|| is_bad_inode(inode
) || inode
->i_generation
!= fh
[1]) {
581 int i_logstart
= fh
[3] & 0x0fffffff;
583 i_pos
= (loff_t
)fh
[2] << 8;
584 i_pos
|= ((fh
[3] >> 24) & 0xf0) | (fh
[4] >> 28);
586 /* try 2 - see if i_pos is in F-d-c
587 * require i_logstart to be the same
588 * Will fail if you truncate and then re-write
591 inode
= fat_iget(sb
, i_pos
);
592 if (inode
&& MSDOS_I(inode
)->i_logstart
!= i_logstart
) {
598 /* For now, do nothing
599 * What we could do is:
600 * follow the file starting at fh[4], and record
601 * the ".." entry, and the name of the fh[2] entry.
602 * The follow the ".." file finding the next step up.
603 * This way we build a path to the root of
604 * the tree. If this works, we lookup the path and so
605 * get this inode into the cache.
606 * Finally try the fat_iget lookup again
607 * If that fails, then weare totally out of luck
608 * But all that is for another day
612 return ERR_PTR(-ESTALE
);
615 /* now to find a dentry.
616 * If possible, get a well-connected one
618 result
= d_alloc_anon(inode
);
619 if (result
== NULL
) {
621 return ERR_PTR(-ENOMEM
);
623 result
->d_op
= sb
->s_root
->d_op
;
628 fat_encode_fh(struct dentry
*de
, __u32
*fh
, int *lenp
, int connectable
)
631 struct inode
*inode
= de
->d_inode
;
632 u32 ipos_h
, ipos_m
, ipos_l
;
635 return 255; /* no room */
637 ipos_h
= MSDOS_I(inode
)->i_pos
>> 8;
638 ipos_m
= (MSDOS_I(inode
)->i_pos
& 0xf0) << 24;
639 ipos_l
= (MSDOS_I(inode
)->i_pos
& 0x0f) << 28;
641 fh
[0] = inode
->i_ino
;
642 fh
[1] = inode
->i_generation
;
644 fh
[3] = ipos_m
| MSDOS_I(inode
)->i_logstart
;
645 spin_lock(&de
->d_lock
);
646 fh
[4] = ipos_l
| MSDOS_I(de
->d_parent
->d_inode
)->i_logstart
;
647 spin_unlock(&de
->d_lock
);
651 static struct dentry
*fat_get_parent(struct dentry
*child
)
653 struct buffer_head
*bh
;
654 struct msdos_dir_entry
*de
;
656 struct dentry
*parent
;
662 err
= fat_get_dotdot_entry(child
->d_inode
, &bh
, &de
, &i_pos
);
664 parent
= ERR_PTR(err
);
667 inode
= fat_build_inode(child
->d_sb
, de
, i_pos
);
670 parent
= ERR_PTR(PTR_ERR(inode
));
673 parent
= d_alloc_anon(inode
);
676 parent
= ERR_PTR(-ENOMEM
);
684 static struct export_operations fat_export_ops
= {
685 .decode_fh
= fat_decode_fh
,
686 .encode_fh
= fat_encode_fh
,
687 .get_dentry
= fat_get_dentry
,
688 .get_parent
= fat_get_parent
,
691 static int fat_show_options(struct seq_file
*m
, struct vfsmount
*mnt
)
693 struct msdos_sb_info
*sbi
= MSDOS_SB(mnt
->mnt_sb
);
694 struct fat_mount_options
*opts
= &sbi
->options
;
695 int isvfat
= opts
->isvfat
;
697 if (opts
->fs_uid
!= 0)
698 seq_printf(m
, ",uid=%u", opts
->fs_uid
);
699 if (opts
->fs_gid
!= 0)
700 seq_printf(m
, ",gid=%u", opts
->fs_gid
);
701 seq_printf(m
, ",fmask=%04o", opts
->fs_fmask
);
702 seq_printf(m
, ",dmask=%04o", opts
->fs_dmask
);
704 seq_printf(m
, ",codepage=%s", sbi
->nls_disk
->charset
);
707 seq_printf(m
, ",iocharset=%s", sbi
->nls_io
->charset
);
709 switch (opts
->shortname
) {
710 case VFAT_SFN_DISPLAY_WIN95
| VFAT_SFN_CREATE_WIN95
:
711 seq_puts(m
, ",shortname=win95");
713 case VFAT_SFN_DISPLAY_WINNT
| VFAT_SFN_CREATE_WINNT
:
714 seq_puts(m
, ",shortname=winnt");
716 case VFAT_SFN_DISPLAY_WINNT
| VFAT_SFN_CREATE_WIN95
:
717 seq_puts(m
, ",shortname=mixed");
719 case VFAT_SFN_DISPLAY_LOWER
| VFAT_SFN_CREATE_WIN95
:
720 /* seq_puts(m, ",shortname=lower"); */
723 seq_puts(m
, ",shortname=unknown");
727 if (opts
->name_check
!= 'n')
728 seq_printf(m
, ",check=%c", opts
->name_check
);
730 seq_puts(m
, ",quiet");
732 seq_puts(m
, ",showexec");
733 if (opts
->sys_immutable
)
734 seq_puts(m
, ",sys_immutable");
737 seq_puts(m
, ",dotsOK=yes");
739 seq_puts(m
, ",nocase");
742 seq_puts(m
, ",utf8");
743 if (opts
->unicode_xlate
)
744 seq_puts(m
, ",uni_xlate");
746 seq_puts(m
, ",nonumtail");
753 Opt_check_n
, Opt_check_r
, Opt_check_s
, Opt_uid
, Opt_gid
,
754 Opt_umask
, Opt_dmask
, Opt_fmask
, Opt_codepage
, Opt_nocase
,
755 Opt_quiet
, Opt_showexec
, Opt_debug
, Opt_immutable
,
756 Opt_dots
, Opt_nodots
,
757 Opt_charset
, Opt_shortname_lower
, Opt_shortname_win95
,
758 Opt_shortname_winnt
, Opt_shortname_mixed
, Opt_utf8_no
, Opt_utf8_yes
,
759 Opt_uni_xl_no
, Opt_uni_xl_yes
, Opt_nonumtail_no
, Opt_nonumtail_yes
,
760 Opt_obsolate
, Opt_err
,
763 static match_table_t fat_tokens
= {
764 {Opt_check_r
, "check=relaxed"},
765 {Opt_check_s
, "check=strict"},
766 {Opt_check_n
, "check=normal"},
767 {Opt_check_r
, "check=r"},
768 {Opt_check_s
, "check=s"},
769 {Opt_check_n
, "check=n"},
772 {Opt_umask
, "umask=%o"},
773 {Opt_dmask
, "dmask=%o"},
774 {Opt_fmask
, "fmask=%o"},
775 {Opt_codepage
, "codepage=%u"},
776 {Opt_nocase
, "nocase"},
777 {Opt_quiet
, "quiet"},
778 {Opt_showexec
, "showexec"},
779 {Opt_debug
, "debug"},
780 {Opt_immutable
, "sys_immutable"},
781 {Opt_obsolate
, "conv=binary"},
782 {Opt_obsolate
, "conv=text"},
783 {Opt_obsolate
, "conv=auto"},
784 {Opt_obsolate
, "conv=b"},
785 {Opt_obsolate
, "conv=t"},
786 {Opt_obsolate
, "conv=a"},
787 {Opt_obsolate
, "fat=%u"},
788 {Opt_obsolate
, "blocksize=%u"},
789 {Opt_obsolate
, "cvf_format=%20s"},
790 {Opt_obsolate
, "cvf_options=%100s"},
791 {Opt_obsolate
, "posix"},
794 static match_table_t msdos_tokens
= {
795 {Opt_nodots
, "nodots"},
796 {Opt_nodots
, "dotsOK=no"},
798 {Opt_dots
, "dotsOK=yes"},
801 static match_table_t vfat_tokens
= {
802 {Opt_charset
, "iocharset=%s"},
803 {Opt_shortname_lower
, "shortname=lower"},
804 {Opt_shortname_win95
, "shortname=win95"},
805 {Opt_shortname_winnt
, "shortname=winnt"},
806 {Opt_shortname_mixed
, "shortname=mixed"},
807 {Opt_utf8_no
, "utf8=0"}, /* 0 or no or false */
808 {Opt_utf8_no
, "utf8=no"},
809 {Opt_utf8_no
, "utf8=false"},
810 {Opt_utf8_yes
, "utf8=1"}, /* empty or 1 or yes or true */
811 {Opt_utf8_yes
, "utf8=yes"},
812 {Opt_utf8_yes
, "utf8=true"},
813 {Opt_utf8_yes
, "utf8"},
814 {Opt_uni_xl_no
, "uni_xlate=0"}, /* 0 or no or false */
815 {Opt_uni_xl_no
, "uni_xlate=no"},
816 {Opt_uni_xl_no
, "uni_xlate=false"},
817 {Opt_uni_xl_yes
, "uni_xlate=1"}, /* empty or 1 or yes or true */
818 {Opt_uni_xl_yes
, "uni_xlate=yes"},
819 {Opt_uni_xl_yes
, "uni_xlate=true"},
820 {Opt_uni_xl_yes
, "uni_xlate"},
821 {Opt_nonumtail_no
, "nonumtail=0"}, /* 0 or no or false */
822 {Opt_nonumtail_no
, "nonumtail=no"},
823 {Opt_nonumtail_no
, "nonumtail=false"},
824 {Opt_nonumtail_yes
, "nonumtail=1"}, /* empty or 1 or yes or true */
825 {Opt_nonumtail_yes
, "nonumtail=yes"},
826 {Opt_nonumtail_yes
, "nonumtail=true"},
827 {Opt_nonumtail_yes
, "nonumtail"},
831 static int parse_options(char *options
, int is_vfat
, int *debug
,
832 struct fat_mount_options
*opts
)
835 substring_t args
[MAX_OPT_ARGS
];
839 opts
->isvfat
= is_vfat
;
841 opts
->fs_uid
= current
->uid
;
842 opts
->fs_gid
= current
->gid
;
843 opts
->fs_fmask
= opts
->fs_dmask
= current
->fs
->umask
;
844 opts
->codepage
= fat_default_codepage
;
845 opts
->iocharset
= fat_default_iocharset
;
847 opts
->shortname
= VFAT_SFN_DISPLAY_LOWER
|VFAT_SFN_CREATE_WIN95
;
850 opts
->name_check
= 'n';
851 opts
->quiet
= opts
->showexec
= opts
->sys_immutable
= opts
->dotsOK
= 0;
852 opts
->utf8
= opts
->unicode_xlate
= 0;
860 while ((p
= strsep(&options
, ",")) != NULL
) {
865 token
= match_token(p
, fat_tokens
, args
);
866 if (token
== Opt_err
) {
868 token
= match_token(p
, vfat_tokens
, args
);
870 token
= match_token(p
, msdos_tokens
, args
);
874 opts
->name_check
= 's';
877 opts
->name_check
= 'r';
880 opts
->name_check
= 'n';
886 /* for backward compatibility */
887 opts
->shortname
= VFAT_SFN_DISPLAY_WIN95
888 | VFAT_SFN_CREATE_WIN95
;
901 opts
->sys_immutable
= 1;
904 if (match_int(&args
[0], &option
))
906 opts
->fs_uid
= option
;
909 if (match_int(&args
[0], &option
))
911 opts
->fs_gid
= option
;
914 if (match_octal(&args
[0], &option
))
916 opts
->fs_fmask
= opts
->fs_dmask
= option
;
919 if (match_octal(&args
[0], &option
))
921 opts
->fs_dmask
= option
;
924 if (match_octal(&args
[0], &option
))
926 opts
->fs_fmask
= option
;
929 if (match_int(&args
[0], &option
))
931 opts
->codepage
= option
;
944 if (opts
->iocharset
!= fat_default_iocharset
)
945 kfree(opts
->iocharset
);
946 iocharset
= match_strdup(&args
[0]);
949 opts
->iocharset
= iocharset
;
951 case Opt_shortname_lower
:
952 opts
->shortname
= VFAT_SFN_DISPLAY_LOWER
953 | VFAT_SFN_CREATE_WIN95
;
955 case Opt_shortname_win95
:
956 opts
->shortname
= VFAT_SFN_DISPLAY_WIN95
957 | VFAT_SFN_CREATE_WIN95
;
959 case Opt_shortname_winnt
:
960 opts
->shortname
= VFAT_SFN_DISPLAY_WINNT
961 | VFAT_SFN_CREATE_WINNT
;
963 case Opt_shortname_mixed
:
964 opts
->shortname
= VFAT_SFN_DISPLAY_WINNT
965 | VFAT_SFN_CREATE_WIN95
;
967 case Opt_utf8_no
: /* 0 or no or false */
970 case Opt_utf8_yes
: /* empty or 1 or yes or true */
973 case Opt_uni_xl_no
: /* 0 or no or false */
974 opts
->unicode_xlate
= 0;
976 case Opt_uni_xl_yes
: /* empty or 1 or yes or true */
977 opts
->unicode_xlate
= 1;
979 case Opt_nonumtail_no
: /* 0 or no or false */
980 opts
->numtail
= 1; /* negated option */
982 case Opt_nonumtail_yes
: /* empty or 1 or yes or true */
983 opts
->numtail
= 0; /* negated option */
986 /* obsolete mount options */
988 printk(KERN_INFO
"FAT: \"%s\" option is obsolete, "
989 "not supported now\n", p
);
993 printk(KERN_ERR
"FAT: Unrecognized mount option \"%s\" "
994 "or missing value\n", p
);
998 /* UTF8 doesn't provide FAT semantics */
999 if (!strcmp(opts
->iocharset
, "utf8")) {
1000 printk(KERN_ERR
"FAT: utf8 is not a recommended IO charset"
1001 " for FAT filesystems, filesystem will be case sensitive!\n");
1004 if (opts
->unicode_xlate
)
1010 static int fat_read_root(struct inode
*inode
)
1012 struct super_block
*sb
= inode
->i_sb
;
1013 struct msdos_sb_info
*sbi
= MSDOS_SB(sb
);
1016 MSDOS_I(inode
)->i_pos
= 0;
1017 inode
->i_uid
= sbi
->options
.fs_uid
;
1018 inode
->i_gid
= sbi
->options
.fs_gid
;
1020 inode
->i_generation
= 0;
1021 inode
->i_mode
= (S_IRWXUGO
& ~sbi
->options
.fs_dmask
) | S_IFDIR
;
1022 inode
->i_op
= sbi
->dir_ops
;
1023 inode
->i_fop
= &fat_dir_operations
;
1024 if (sbi
->fat_bits
== 32) {
1025 MSDOS_I(inode
)->i_start
= sbi
->root_cluster
;
1026 error
= fat_calc_dir_size(inode
);
1030 MSDOS_I(inode
)->i_start
= 0;
1031 inode
->i_size
= sbi
->dir_entries
* sizeof(struct msdos_dir_entry
);
1033 inode
->i_blksize
= sbi
->cluster_size
;
1034 inode
->i_blocks
= ((inode
->i_size
+ (sbi
->cluster_size
- 1))
1035 & ~((loff_t
)sbi
->cluster_size
- 1)) >> 9;
1036 MSDOS_I(inode
)->i_logstart
= 0;
1037 MSDOS_I(inode
)->mmu_private
= inode
->i_size
;
1039 MSDOS_I(inode
)->i_attrs
= ATTR_NONE
;
1040 inode
->i_mtime
.tv_sec
= inode
->i_atime
.tv_sec
= inode
->i_ctime
.tv_sec
= 0;
1041 inode
->i_mtime
.tv_nsec
= inode
->i_atime
.tv_nsec
= inode
->i_ctime
.tv_nsec
= 0;
1042 inode
->i_nlink
= fat_subdirs(inode
)+2;
1048 * Read the super block of an MS-DOS FS.
1050 int fat_fill_super(struct super_block
*sb
, void *data
, int silent
,
1051 struct inode_operations
*fs_dir_inode_ops
, int isvfat
)
1053 struct inode
*root_inode
= NULL
;
1054 struct buffer_head
*bh
;
1055 struct fat_boot_sector
*b
;
1056 struct msdos_sb_info
*sbi
;
1057 u16 logical_sector_size
;
1058 u32 total_sectors
, total_clusters
, fat_clusters
, rootdir_sectors
;
1064 sbi
= kmalloc(sizeof(struct msdos_sb_info
), GFP_KERNEL
);
1067 sb
->s_fs_info
= sbi
;
1068 memset(sbi
, 0, sizeof(struct msdos_sb_info
));
1070 sb
->s_flags
|= MS_NODIRATIME
;
1071 sb
->s_magic
= MSDOS_SUPER_MAGIC
;
1072 sb
->s_op
= &fat_sops
;
1073 sb
->s_export_op
= &fat_export_ops
;
1074 sbi
->dir_ops
= fs_dir_inode_ops
;
1076 error
= parse_options(data
, isvfat
, &debug
, &sbi
->options
);
1081 sb_min_blocksize(sb
, 512);
1082 bh
= sb_bread(sb
, 0);
1084 printk(KERN_ERR
"FAT: unable to read boot sector\n");
1088 b
= (struct fat_boot_sector
*) bh
->b_data
;
1091 printk(KERN_ERR
"FAT: bogus number of reserved sectors\n");
1097 printk(KERN_ERR
"FAT: bogus number of FAT structure\n");
1103 * Earlier we checked here that b->secs_track and b->head are nonzero,
1104 * but it turns out valid FAT filesystems can have zero there.
1108 if (!FAT_VALID_MEDIA(media
)) {
1110 printk(KERN_ERR
"FAT: invalid media value (0x%02x)\n",
1115 logical_sector_size
=
1116 le16_to_cpu(get_unaligned((__le16
*)&b
->sector_size
));
1117 if (!logical_sector_size
1118 || (logical_sector_size
& (logical_sector_size
- 1))
1119 || (logical_sector_size
< 512)
1120 || (PAGE_CACHE_SIZE
< logical_sector_size
)) {
1122 printk(KERN_ERR
"FAT: bogus logical sector size %u\n",
1123 logical_sector_size
);
1127 sbi
->sec_per_clus
= b
->sec_per_clus
;
1128 if (!sbi
->sec_per_clus
1129 || (sbi
->sec_per_clus
& (sbi
->sec_per_clus
- 1))) {
1131 printk(KERN_ERR
"FAT: bogus sectors per cluster %u\n",
1137 if (logical_sector_size
< sb
->s_blocksize
) {
1138 printk(KERN_ERR
"FAT: logical sector size too small for device"
1139 " (logical sector size = %u)\n", logical_sector_size
);
1143 if (logical_sector_size
> sb
->s_blocksize
) {
1146 if (!sb_set_blocksize(sb
, logical_sector_size
)) {
1147 printk(KERN_ERR
"FAT: unable to set blocksize %u\n",
1148 logical_sector_size
);
1151 bh
= sb_bread(sb
, 0);
1153 printk(KERN_ERR
"FAT: unable to read boot sector"
1154 " (logical sector size = %lu)\n",
1158 b
= (struct fat_boot_sector
*) bh
->b_data
;
1161 sbi
->cluster_size
= sb
->s_blocksize
* sbi
->sec_per_clus
;
1162 sbi
->cluster_bits
= ffs(sbi
->cluster_size
) - 1;
1163 sbi
->fats
= b
->fats
;
1164 sbi
->fat_bits
= 0; /* Don't know yet */
1165 sbi
->fat_start
= le16_to_cpu(b
->reserved
);
1166 sbi
->fat_length
= le16_to_cpu(b
->fat_length
);
1167 sbi
->root_cluster
= 0;
1168 sbi
->free_clusters
= -1; /* Don't know yet */
1169 sbi
->prev_free
= FAT_START_ENT
;
1171 if (!sbi
->fat_length
&& b
->fat32_length
) {
1172 struct fat_boot_fsinfo
*fsinfo
;
1173 struct buffer_head
*fsinfo_bh
;
1177 sbi
->fat_length
= le32_to_cpu(b
->fat32_length
);
1178 sbi
->root_cluster
= le32_to_cpu(b
->root_cluster
);
1180 sb
->s_maxbytes
= 0xffffffff;
1182 /* MC - if info_sector is 0, don't multiply by 0 */
1183 sbi
->fsinfo_sector
= le16_to_cpu(b
->info_sector
);
1184 if (sbi
->fsinfo_sector
== 0)
1185 sbi
->fsinfo_sector
= 1;
1187 fsinfo_bh
= sb_bread(sb
, sbi
->fsinfo_sector
);
1188 if (fsinfo_bh
== NULL
) {
1189 printk(KERN_ERR
"FAT: bread failed, FSINFO block"
1190 " (sector = %lu)\n", sbi
->fsinfo_sector
);
1195 fsinfo
= (struct fat_boot_fsinfo
*)fsinfo_bh
->b_data
;
1196 if (!IS_FSINFO(fsinfo
)) {
1198 "FAT: Did not find valid FSINFO signature.\n"
1199 " Found signature1 0x%08x signature2 0x%08x"
1200 " (sector = %lu)\n",
1201 le32_to_cpu(fsinfo
->signature1
),
1202 le32_to_cpu(fsinfo
->signature2
),
1203 sbi
->fsinfo_sector
);
1205 sbi
->free_clusters
= le32_to_cpu(fsinfo
->free_clusters
);
1206 sbi
->prev_free
= le32_to_cpu(fsinfo
->next_cluster
);
1212 sbi
->dir_per_block
= sb
->s_blocksize
/ sizeof(struct msdos_dir_entry
);
1213 sbi
->dir_per_block_bits
= ffs(sbi
->dir_per_block
) - 1;
1215 sbi
->dir_start
= sbi
->fat_start
+ sbi
->fats
* sbi
->fat_length
;
1217 le16_to_cpu(get_unaligned((__le16
*)&b
->dir_entries
));
1218 if (sbi
->dir_entries
& (sbi
->dir_per_block
- 1)) {
1220 printk(KERN_ERR
"FAT: bogus directroy-entries per block"
1221 " (%u)\n", sbi
->dir_entries
);
1226 rootdir_sectors
= sbi
->dir_entries
1227 * sizeof(struct msdos_dir_entry
) / sb
->s_blocksize
;
1228 sbi
->data_start
= sbi
->dir_start
+ rootdir_sectors
;
1229 total_sectors
= le16_to_cpu(get_unaligned((__le16
*)&b
->sectors
));
1230 if (total_sectors
== 0)
1231 total_sectors
= le32_to_cpu(b
->total_sect
);
1233 total_clusters
= (total_sectors
- sbi
->data_start
) / sbi
->sec_per_clus
;
1235 if (sbi
->fat_bits
!= 32)
1236 sbi
->fat_bits
= (total_clusters
> MAX_FAT12
) ? 16 : 12;
1238 /* check that FAT table does not overflow */
1239 fat_clusters
= sbi
->fat_length
* sb
->s_blocksize
* 8 / sbi
->fat_bits
;
1240 total_clusters
= min(total_clusters
, fat_clusters
- FAT_START_ENT
);
1241 if (total_clusters
> MAX_FAT(sb
)) {
1243 printk(KERN_ERR
"FAT: count of clusters too big (%u)\n",
1249 sbi
->max_cluster
= total_clusters
+ FAT_START_ENT
;
1250 /* check the free_clusters, it's not necessarily correct */
1251 if (sbi
->free_clusters
!= -1 && sbi
->free_clusters
> total_clusters
)
1252 sbi
->free_clusters
= -1;
1253 /* check the prev_free, it's not necessarily correct */
1254 sbi
->prev_free
%= sbi
->max_cluster
;
1255 if (sbi
->prev_free
< FAT_START_ENT
)
1256 sbi
->prev_free
= FAT_START_ENT
;
1260 /* set up enough so that it can read an inode */
1262 fat_ent_access_init(sb
);
1265 * The low byte of FAT's first entry must have same value with
1266 * media-field. But in real world, too many devices is
1267 * writing wrong value. So, removed that validity check.
1269 * if (FAT_FIRST_ENT(sb, media) != first)
1273 sprintf(buf
, "cp%d", sbi
->options
.codepage
);
1274 sbi
->nls_disk
= load_nls(buf
);
1275 if (!sbi
->nls_disk
) {
1276 printk(KERN_ERR
"FAT: codepage %s not found\n", buf
);
1280 /* FIXME: utf8 is using iocharset for upper/lower conversion */
1281 if (sbi
->options
.isvfat
) {
1282 sbi
->nls_io
= load_nls(sbi
->options
.iocharset
);
1284 printk(KERN_ERR
"FAT: IO charset %s not found\n",
1285 sbi
->options
.iocharset
);
1291 root_inode
= new_inode(sb
);
1294 root_inode
->i_ino
= MSDOS_ROOT_INO
;
1295 root_inode
->i_version
= 1;
1296 error
= fat_read_root(root_inode
);
1300 insert_inode_hash(root_inode
);
1301 sb
->s_root
= d_alloc_root(root_inode
);
1303 printk(KERN_ERR
"FAT: get root inode failed\n");
1312 printk(KERN_INFO
"VFS: Can't find a valid FAT filesystem"
1313 " on dev %s.\n", sb
->s_id
);
1319 unload_nls(sbi
->nls_io
);
1321 unload_nls(sbi
->nls_disk
);
1322 if (sbi
->options
.iocharset
!= fat_default_iocharset
)
1323 kfree(sbi
->options
.iocharset
);
1324 sb
->s_fs_info
= NULL
;
1329 EXPORT_SYMBOL(fat_fill_super
);
1331 int __init
fat_cache_init(void);
1332 void fat_cache_destroy(void);
1334 static int __init
init_fat_fs(void)
1338 err
= fat_cache_init();
1342 err
= fat_init_inodecache();
1349 fat_cache_destroy();
1353 static void __exit
exit_fat_fs(void)
1355 fat_cache_destroy();
1356 fat_destroy_inodecache();
1359 module_init(init_fat_fs
)
1360 module_exit(exit_fat_fs
)
1362 MODULE_LICENSE("GPL");