4 * directory handling functions for fat-based filesystems
6 * Written 1992,1993 by Werner Almesberger
8 * Hidden files 1995 by Albert Cahalan <albert@ccs.neu.edu> <adc@coe.neu.edu>
10 * VFAT extensions by Gordon Chaffee <chaffee@plateau.cs.berkeley.edu>
11 * Merged with msdos fs by Henrik Storner <storner@osiris.ping.dk>
12 * Rewritten for constant inumbers. Plugged buffer overrun in readdir(). AV
13 * Short name translation 1999, 2001 by Wolfram Pienkoss <wp@bszh.de>
16 #include <linux/module.h>
17 #include <linux/slab.h>
18 #include <linux/time.h>
19 #include <linux/msdos_fs.h>
20 #include <linux/dirent.h>
21 #include <linux/smp_lock.h>
22 #include <linux/buffer_head.h>
23 #include <asm/uaccess.h>
25 static inline loff_t
fat_make_i_pos(struct super_block
*sb
,
26 struct buffer_head
*bh
,
27 struct msdos_dir_entry
*de
)
29 return ((loff_t
)bh
->b_blocknr
<< MSDOS_SB(sb
)->dir_per_block_bits
)
30 | (de
- (struct msdos_dir_entry
*)bh
->b_data
);
33 static inline void fat_dir_readahead(struct inode
*dir
, sector_t iblock
,
36 struct super_block
*sb
= dir
->i_sb
;
37 struct msdos_sb_info
*sbi
= MSDOS_SB(sb
);
38 struct buffer_head
*bh
;
41 /* This is not a first sector of cluster, or sec_per_clus == 1 */
42 if ((iblock
& (sbi
->sec_per_clus
- 1)) || sbi
->sec_per_clus
== 1)
44 /* root dir of FAT12/FAT16 */
45 if ((sbi
->fat_bits
!= 32) && (dir
->i_ino
== MSDOS_ROOT_INO
))
48 bh
= sb_find_get_block(sb
, phys
);
49 if (bh
== NULL
|| !buffer_uptodate(bh
)) {
50 for (sec
= 0; sec
< sbi
->sec_per_clus
; sec
++)
51 sb_breadahead(sb
, phys
+ sec
);
56 /* Returns the inode number of the directory entry at offset pos. If bh is
57 non-NULL, it is brelse'd before. Pos is incremented. The buffer header is
59 AV. Most often we do it item-by-item. Makes sense to optimize.
60 AV. OK, there we go: if both bh and de are non-NULL we assume that we just
61 AV. want the next entry (took one explicit de=NULL in vfat/namei.c).
62 AV. It's done in fat_get_entry() (inlined), here the slow case lives.
63 AV. Additionally, when we return -1 (i.e. reached the end of directory)
66 static int fat__get_entry(struct inode
*dir
, loff_t
*pos
,
67 struct buffer_head
**bh
, struct msdos_dir_entry
**de
)
69 struct super_block
*sb
= dir
->i_sb
;
70 sector_t phys
, iblock
;
71 unsigned long mapped_blocks
;
79 iblock
= *pos
>> sb
->s_blocksize_bits
;
80 err
= fat_bmap(dir
, iblock
, &phys
, &mapped_blocks
);
82 return -1; /* beyond EOF or error */
84 fat_dir_readahead(dir
, iblock
, phys
);
86 *bh
= sb_bread(sb
, phys
);
88 printk(KERN_ERR
"FAT: Directory bread(block %llu) failed\n",
89 (unsigned long long)phys
);
91 *pos
= (iblock
+ 1) << sb
->s_blocksize_bits
;
95 offset
= *pos
& (sb
->s_blocksize
- 1);
96 *pos
+= sizeof(struct msdos_dir_entry
);
97 *de
= (struct msdos_dir_entry
*)((*bh
)->b_data
+ offset
);
102 static inline int fat_get_entry(struct inode
*dir
, loff_t
*pos
,
103 struct buffer_head
**bh
,
104 struct msdos_dir_entry
**de
)
106 /* Fast stuff first */
108 (*de
- (struct msdos_dir_entry
*)(*bh
)->b_data
) < MSDOS_SB(dir
->i_sb
)->dir_per_block
- 1) {
109 *pos
+= sizeof(struct msdos_dir_entry
);
113 return fat__get_entry(dir
, pos
, bh
, de
);
117 * Convert Unicode 16 to UTF8, translated Unicode, or ASCII.
118 * If uni_xlate is enabled and we can't get a 1:1 conversion, use a
119 * colon as an escape character since it is normally invalid on the vfat
120 * filesystem. The following four characters are the hexadecimal digits
121 * of Unicode value. This lets us do a full dump and restore of Unicode
122 * filenames. We could get into some trouble with long Unicode names,
123 * but ignore that right now.
124 * Ahem... Stack smashing in ring 0 isn't fun. Fixed.
126 static int uni16_to_x8(unsigned char *ascii
, wchar_t *uni
, int uni_xlate
,
127 struct nls_table
*nls
)
130 unsigned char *op
, nc
;
139 if ( (charlen
= nls
->uni2char(ec
, op
, NLS_MAX_CHARSET_SIZE
)) > 0) {
142 if (uni_xlate
== 1) {
144 for (k
= 4; k
> 0; k
--) {
146 op
[k
] = nc
> 9 ? nc
+ ('a' - 10)
155 /* We have some slack there, so it's OK */
166 fat_short2uni(struct nls_table
*t
, unsigned char *c
, int clen
, wchar_t *uni
)
170 charlen
= t
->char2uni(c
, clen
, uni
);
172 *uni
= 0x003f; /* a question mark */
179 fat_short2lower_uni(struct nls_table
*t
, unsigned char *c
, int clen
, wchar_t *uni
)
184 charlen
= t
->char2uni(c
, clen
, &wc
);
186 *uni
= 0x003f; /* a question mark */
188 } else if (charlen
<= 1) {
189 unsigned char nc
= t
->charset2lower
[*c
];
194 if ( (charlen
= t
->char2uni(&nc
, 1, uni
)) < 0) {
195 *uni
= 0x003f; /* a question mark */
205 fat_shortname2uni(struct nls_table
*nls
, unsigned char *buf
, int buf_size
,
206 wchar_t *uni_buf
, unsigned short opt
, int lower
)
210 if (opt
& VFAT_SFN_DISPLAY_LOWER
)
211 len
= fat_short2lower_uni(nls
, buf
, buf_size
, uni_buf
);
212 else if (opt
& VFAT_SFN_DISPLAY_WIN95
)
213 len
= fat_short2uni(nls
, buf
, buf_size
, uni_buf
);
214 else if (opt
& VFAT_SFN_DISPLAY_WINNT
) {
216 len
= fat_short2lower_uni(nls
, buf
, buf_size
, uni_buf
);
218 len
= fat_short2uni(nls
, buf
, buf_size
, uni_buf
);
220 len
= fat_short2uni(nls
, buf
, buf_size
, uni_buf
);
225 enum { PARSE_INVALID
= 1, PARSE_NOT_LONGNAME
, PARSE_EOF
, };
228 * fat_parse_long - Parse extended directory entry.
230 * This function returns zero on success, negative value on error, or one of
233 * %PARSE_INVALID - Directory entry is invalid.
234 * %PARSE_NOT_LONGNAME - Directory entry does not contain longname.
235 * %PARSE_EOF - Directory has no more entries.
237 static int fat_parse_long(struct inode
*dir
, loff_t
*pos
,
238 struct buffer_head
**bh
, struct msdos_dir_entry
**de
,
239 wchar_t **unicode
, unsigned char *nr_slots
)
241 struct msdos_dir_slot
*ds
;
242 unsigned char id
, slot
, slots
, alias_checksum
;
245 *unicode
= (wchar_t *)__get_free_page(GFP_KERNEL
);
253 ds
= (struct msdos_dir_slot
*)*de
;
256 return PARSE_INVALID
;
258 if (slots
> 20 || !slots
) /* ceil(256 * 2 / 26) */
259 return PARSE_INVALID
;
261 alias_checksum
= ds
->alias_checksum
;
269 fat16_towchar(*unicode
+ offset
, ds
->name0_4
, 5);
270 fat16_towchar(*unicode
+ offset
+ 5, ds
->name5_10
, 6);
271 fat16_towchar(*unicode
+ offset
+ 11, ds
->name11_12
, 2);
274 (*unicode
)[offset
+ 13] = 0;
275 if (fat_get_entry(dir
, pos
, bh
, de
) < 0)
279 ds
= (struct msdos_dir_slot
*)*de
;
280 if (ds
->attr
!= ATTR_EXT
)
281 return PARSE_NOT_LONGNAME
;
282 if ((ds
->id
& ~0x40) != slot
)
284 if (ds
->alias_checksum
!= alias_checksum
)
287 if ((*de
)->name
[0] == DELETED_FLAG
)
288 return PARSE_INVALID
;
289 if ((*de
)->attr
== ATTR_EXT
)
291 if (IS_FREE((*de
)->name
) || ((*de
)->attr
& ATTR_VOLUME
))
292 return PARSE_INVALID
;
293 if (fat_checksum((*de
)->name
) != alias_checksum
)
300 * Return values: negative -> error, 0 -> not found, positive -> found,
301 * value is the total amount of slots, including the shortname entry.
303 int fat_search_long(struct inode
*inode
, const unsigned char *name
,
304 int name_len
, struct fat_slot_info
*sinfo
)
306 struct super_block
*sb
= inode
->i_sb
;
307 struct msdos_sb_info
*sbi
= MSDOS_SB(sb
);
308 struct buffer_head
*bh
= NULL
;
309 struct msdos_dir_entry
*de
;
310 struct nls_table
*nls_io
= sbi
->nls_io
;
311 struct nls_table
*nls_disk
= sbi
->nls_disk
;
312 wchar_t bufuname
[14];
313 unsigned char xlate_len
, nr_slots
;
314 wchar_t *unicode
= NULL
;
315 unsigned char work
[8], bufname
[260]; /* 256 + 4 */
316 int uni_xlate
= sbi
->options
.unicode_xlate
;
317 int utf8
= sbi
->options
.utf8
;
318 int anycase
= (sbi
->options
.name_check
!= 's');
319 unsigned short opt_shortname
= sbi
->options
.shortname
;
321 int chl
, i
, j
, last_u
, err
;
325 if (fat_get_entry(inode
, &cpos
, &bh
, &de
) == -1)
329 if (de
->name
[0] == DELETED_FLAG
)
331 if (de
->attr
!= ATTR_EXT
&& (de
->attr
& ATTR_VOLUME
))
333 if (de
->attr
!= ATTR_EXT
&& IS_FREE(de
->name
))
335 if (de
->attr
== ATTR_EXT
) {
336 int status
= fat_parse_long(inode
, &cpos
, &bh
, &de
,
337 &unicode
, &nr_slots
);
340 else if (status
== PARSE_INVALID
)
342 else if (status
== PARSE_NOT_LONGNAME
)
344 else if (status
== PARSE_EOF
)
348 memcpy(work
, de
->name
, sizeof(de
->name
));
349 /* see namei.c, msdos_format_name */
352 for (i
= 0, j
= 0, last_u
= 0; i
< 8;) {
354 chl
= fat_shortname2uni(nls_disk
, &work
[i
], 8 - i
,
355 &bufuname
[j
++], opt_shortname
,
356 de
->lcase
& CASE_LOWER_BASE
);
366 fat_short2uni(nls_disk
, ".", 1, &bufuname
[j
++]);
367 for (i
= 0; i
< 3;) {
368 if (!de
->ext
[i
]) break;
369 chl
= fat_shortname2uni(nls_disk
, &de
->ext
[i
], 3 - i
,
370 &bufuname
[j
++], opt_shortname
,
371 de
->lcase
& CASE_LOWER_EXT
);
373 if (de
->ext
[i
] != ' ')
383 bufuname
[last_u
] = 0x0000;
385 ?utf8_wcstombs(bufname
, bufuname
, sizeof(bufname
))
386 :uni16_to_x8(bufname
, bufuname
, uni_xlate
, nls_io
);
387 if (xlate_len
== name_len
)
388 if ((!anycase
&& !memcmp(name
, bufname
, xlate_len
)) ||
389 (anycase
&& !nls_strnicmp(nls_io
, name
, bufname
,
395 ?utf8_wcstombs(bufname
, unicode
, sizeof(bufname
))
396 :uni16_to_x8(bufname
, unicode
, uni_xlate
, nls_io
);
397 if (xlate_len
!= name_len
)
399 if ((!anycase
&& !memcmp(name
, bufname
, xlate_len
)) ||
400 (anycase
&& !nls_strnicmp(nls_io
, name
, bufname
,
407 nr_slots
++; /* include the de */
408 sinfo
->slot_off
= cpos
- nr_slots
* sizeof(*de
);
409 sinfo
->nr_slots
= nr_slots
;
412 sinfo
->i_pos
= fat_make_i_pos(sb
, sinfo
->bh
, sinfo
->de
);
416 free_page((unsigned long)unicode
);
421 EXPORT_SYMBOL_GPL(fat_search_long
);
423 struct fat_ioctl_filldir_callback
{
424 struct dirent __user
*dirent
;
427 const char *longname
;
429 const char *shortname
;
433 static int __fat_readdir(struct inode
*inode
, struct file
*filp
, void *dirent
,
434 filldir_t filldir
, int short_only
, int both
)
436 struct super_block
*sb
= inode
->i_sb
;
437 struct msdos_sb_info
*sbi
= MSDOS_SB(sb
);
438 struct buffer_head
*bh
;
439 struct msdos_dir_entry
*de
;
440 struct nls_table
*nls_io
= sbi
->nls_io
;
441 struct nls_table
*nls_disk
= sbi
->nls_disk
;
442 unsigned char long_slots
;
443 const char *fill_name
;
445 wchar_t bufuname
[14];
446 wchar_t *unicode
= NULL
;
447 unsigned char c
, work
[8], bufname
[56], *ptname
= bufname
;
448 unsigned long lpos
, dummy
, *furrfu
= &lpos
;
449 int uni_xlate
= sbi
->options
.unicode_xlate
;
450 int isvfat
= sbi
->options
.isvfat
;
451 int utf8
= sbi
->options
.utf8
;
452 int nocase
= sbi
->options
.nocase
;
453 unsigned short opt_shortname
= sbi
->options
.shortname
;
455 int chi
, chl
, i
, i2
, j
, last
, last_u
, dotoffset
= 0;
462 /* Fake . and .. for the root directory. */
463 if (inode
->i_ino
== MSDOS_ROOT_INO
) {
465 if (filldir(dirent
, "..", cpos
+1, cpos
, MSDOS_ROOT_INO
, DT_DIR
) < 0)
476 if (cpos
& (sizeof(struct msdos_dir_entry
)-1)) {
483 if (fat_get_entry(inode
, &cpos
, &bh
, &de
) == -1)
487 /* Check for long filename entry */
489 if (de
->name
[0] == DELETED_FLAG
)
491 if (de
->attr
!= ATTR_EXT
&& (de
->attr
& ATTR_VOLUME
))
493 if (de
->attr
!= ATTR_EXT
&& IS_FREE(de
->name
))
496 if ((de
->attr
& ATTR_VOLUME
) || IS_FREE(de
->name
))
500 if (isvfat
&& de
->attr
== ATTR_EXT
) {
501 int status
= fat_parse_long(inode
, &cpos
, &bh
, &de
,
502 &unicode
, &long_slots
);
507 } else if (status
== PARSE_INVALID
)
509 else if (status
== PARSE_NOT_LONGNAME
)
511 else if (status
== PARSE_EOF
)
515 if (sbi
->options
.dotsOK
) {
518 if (de
->attr
& ATTR_HIDDEN
) {
524 memcpy(work
, de
->name
, sizeof(de
->name
));
525 /* see namei.c, msdos_format_name */
528 for (i
= 0, j
= 0, last
= 0, last_u
= 0; i
< 8;) {
529 if (!(c
= work
[i
])) break;
530 chl
= fat_shortname2uni(nls_disk
, &work
[i
], 8 - i
,
531 &bufuname
[j
++], opt_shortname
,
532 de
->lcase
& CASE_LOWER_BASE
);
534 ptname
[i
++] = (!nocase
&& c
>='A' && c
<='Z') ? c
+32 : c
;
541 for (chi
= 0; chi
< chl
&& i
< 8; chi
++) {
549 fat_short2uni(nls_disk
, ".", 1, &bufuname
[j
++]);
551 for (i2
= 0; i2
< 3;) {
552 if (!(c
= de
->ext
[i2
])) break;
553 chl
= fat_shortname2uni(nls_disk
, &de
->ext
[i2
], 3 - i2
,
554 &bufuname
[j
++], opt_shortname
,
555 de
->lcase
& CASE_LOWER_EXT
);
558 ptname
[i
++] = (!nocase
&& c
>='A' && c
<='Z') ? c
+32 : c
;
565 for (chi
= 0; chi
< chl
&& i2
< 3; chi
++) {
566 ptname
[i
++] = de
->ext
[i2
++];
574 i
= last
+ dotoffset
;
577 lpos
= cpos
- (long_slots
+1)*sizeof(struct msdos_dir_entry
);
578 if (!memcmp(de
->name
, MSDOS_DOT
, MSDOS_NAME
))
580 else if (!memcmp(de
->name
, MSDOS_DOTDOT
, MSDOS_NAME
)) {
581 inum
= parent_ino(filp
->f_dentry
);
583 loff_t i_pos
= fat_make_i_pos(sb
, bh
, de
);
584 struct inode
*tmp
= fat_iget(sb
, i_pos
);
589 inum
= iunique(sb
, MSDOS_ROOT_INO
);
593 bufuname
[j
] = 0x0000;
594 i
= utf8
? utf8_wcstombs(bufname
, bufuname
, sizeof(bufname
))
595 : uni16_to_x8(bufname
, bufuname
, uni_xlate
, nls_io
);
600 if (!short_only
&& long_slots
) {
601 /* convert the unicode long name. 261 is maximum size
602 * of unicode buffer. (13 * slots + nul) */
603 void *longname
= unicode
+ 261;
604 int buf_size
= PAGE_SIZE
- (261 * sizeof(unicode
[0]));
606 ? utf8_wcstombs(longname
, unicode
, buf_size
)
607 : uni16_to_x8(longname
, unicode
, uni_xlate
, nls_io
);
610 fill_name
= longname
;
613 /* hack for fat_ioctl_filldir() */
614 struct fat_ioctl_filldir_callback
*p
= dirent
;
616 p
->longname
= longname
;
617 p
->long_len
= long_len
;
618 p
->shortname
= bufname
;
624 if (filldir(dirent
, fill_name
, fill_len
, *furrfu
, inum
,
625 (de
->attr
& ATTR_DIR
) ? DT_DIR
: DT_REG
) < 0)
637 free_page((unsigned long)unicode
);
643 static int fat_readdir(struct file
*filp
, void *dirent
, filldir_t filldir
)
645 struct inode
*inode
= filp
->f_dentry
->d_inode
;
646 return __fat_readdir(inode
, filp
, dirent
, filldir
, 0, 0);
649 static int fat_ioctl_filldir(void *__buf
, const char *name
, int name_len
,
650 loff_t offset
, ino_t ino
, unsigned int d_type
)
652 struct fat_ioctl_filldir_callback
*buf
= __buf
;
653 struct dirent __user
*d1
= buf
->dirent
;
654 struct dirent __user
*d2
= d1
+ 1;
661 /* dirent has only short name */
662 if (name_len
>= sizeof(d1
->d_name
))
663 name_len
= sizeof(d1
->d_name
) - 1;
665 if (put_user(0, d2
->d_name
) ||
666 put_user(0, &d2
->d_reclen
) ||
667 copy_to_user(d1
->d_name
, name
, name_len
) ||
668 put_user(0, d1
->d_name
+ name_len
) ||
669 put_user(name_len
, &d1
->d_reclen
))
672 /* dirent has short and long name */
673 const char *longname
= buf
->longname
;
674 int long_len
= buf
->long_len
;
675 const char *shortname
= buf
->shortname
;
676 int short_len
= buf
->short_len
;
678 if (long_len
>= sizeof(d1
->d_name
))
679 long_len
= sizeof(d1
->d_name
) - 1;
680 if (short_len
>= sizeof(d1
->d_name
))
681 short_len
= sizeof(d1
->d_name
) - 1;
683 if (copy_to_user(d2
->d_name
, longname
, long_len
) ||
684 put_user(0, d2
->d_name
+ long_len
) ||
685 put_user(long_len
, &d2
->d_reclen
) ||
686 put_user(ino
, &d2
->d_ino
) ||
687 put_user(offset
, &d2
->d_off
) ||
688 copy_to_user(d1
->d_name
, shortname
, short_len
) ||
689 put_user(0, d1
->d_name
+ short_len
) ||
690 put_user(short_len
, &d1
->d_reclen
))
695 buf
->result
= -EFAULT
;
699 static int fat_dir_ioctl(struct inode
* inode
, struct file
* filp
,
700 unsigned int cmd
, unsigned long arg
)
702 struct fat_ioctl_filldir_callback buf
;
703 struct dirent __user
*d1
;
704 int ret
, short_only
, both
;
707 case VFAT_IOCTL_READDIR_SHORT
:
711 case VFAT_IOCTL_READDIR_BOTH
:
716 return fat_generic_ioctl(inode
, filp
, cmd
, arg
);
719 d1
= (struct dirent __user
*)arg
;
720 if (!access_ok(VERIFY_WRITE
, d1
, sizeof(struct dirent
[2])))
723 * Yes, we don't need this put_user() absolutely. However old
724 * code didn't return the right value. So, app use this value,
725 * in order to check whether it is EOF.
727 if (put_user(0, &d1
->d_reclen
))
734 if (!IS_DEADDIR(inode
)) {
735 ret
= __fat_readdir(inode
, filp
, &buf
, fat_ioctl_filldir
,
744 struct file_operations fat_dir_operations
= {
745 .read
= generic_read_dir
,
746 .readdir
= fat_readdir
,
747 .ioctl
= fat_dir_ioctl
,
751 static int fat_get_short_entry(struct inode
*dir
, loff_t
*pos
,
752 struct buffer_head
**bh
,
753 struct msdos_dir_entry
**de
)
755 while (fat_get_entry(dir
, pos
, bh
, de
) >= 0) {
756 /* free entry or long name entry or volume label */
757 if (!IS_FREE((*de
)->name
) && !((*de
)->attr
& ATTR_VOLUME
))
764 * The ".." entry can not provide the "struct fat_slot_info" informations
765 * for inode. So, this function provide the some informations only.
767 int fat_get_dotdot_entry(struct inode
*dir
, struct buffer_head
**bh
,
768 struct msdos_dir_entry
**de
, loff_t
*i_pos
)
774 while (fat_get_short_entry(dir
, &offset
, bh
, de
) >= 0) {
775 if (!strncmp((*de
)->name
, MSDOS_DOTDOT
, MSDOS_NAME
)) {
776 *i_pos
= fat_make_i_pos(dir
->i_sb
, *bh
, *de
);
783 EXPORT_SYMBOL_GPL(fat_get_dotdot_entry
);
785 /* See if directory is empty */
786 int fat_dir_empty(struct inode
*dir
)
788 struct buffer_head
*bh
;
789 struct msdos_dir_entry
*de
;
795 while (fat_get_short_entry(dir
, &cpos
, &bh
, &de
) >= 0) {
796 if (strncmp(de
->name
, MSDOS_DOT
, MSDOS_NAME
) &&
797 strncmp(de
->name
, MSDOS_DOTDOT
, MSDOS_NAME
)) {
806 EXPORT_SYMBOL_GPL(fat_dir_empty
);
809 * fat_subdirs counts the number of sub-directories of dir. It can be run
810 * on directories being created.
812 int fat_subdirs(struct inode
*dir
)
814 struct buffer_head
*bh
;
815 struct msdos_dir_entry
*de
;
821 while (fat_get_short_entry(dir
, &cpos
, &bh
, &de
) >= 0) {
822 if (de
->attr
& ATTR_DIR
)
830 * Scans a directory for a given file (name points to its formatted name).
831 * Returns an error code or zero.
833 int fat_scan(struct inode
*dir
, const unsigned char *name
,
834 struct fat_slot_info
*sinfo
)
836 struct super_block
*sb
= dir
->i_sb
;
840 while (fat_get_short_entry(dir
, &sinfo
->slot_off
, &sinfo
->bh
,
842 if (!strncmp(sinfo
->de
->name
, name
, MSDOS_NAME
)) {
843 sinfo
->slot_off
-= sizeof(*sinfo
->de
);
845 sinfo
->i_pos
= fat_make_i_pos(sb
, sinfo
->bh
, sinfo
->de
);
852 EXPORT_SYMBOL_GPL(fat_scan
);
854 static int __fat_remove_entries(struct inode
*dir
, loff_t pos
, int nr_slots
)
856 struct super_block
*sb
= dir
->i_sb
;
857 struct buffer_head
*bh
;
858 struct msdos_dir_entry
*de
, *endp
;
859 int err
= 0, orig_slots
;
863 if (fat_get_entry(dir
, &pos
, &bh
, &de
) < 0) {
868 orig_slots
= nr_slots
;
869 endp
= (struct msdos_dir_entry
*)(bh
->b_data
+ sb
->s_blocksize
);
870 while (nr_slots
&& de
< endp
) {
871 de
->name
[0] = DELETED_FLAG
;
875 mark_buffer_dirty(bh
);
877 err
= sync_dirty_buffer(bh
);
882 /* pos is *next* de's position, so this does `- sizeof(de)' */
883 pos
+= ((orig_slots
- nr_slots
) * sizeof(*de
)) - sizeof(*de
);
889 int fat_remove_entries(struct inode
*dir
, struct fat_slot_info
*sinfo
)
891 struct msdos_dir_entry
*de
;
892 struct buffer_head
*bh
;
893 int err
= 0, nr_slots
;
896 * First stage: Remove the shortname. By this, the directory
899 nr_slots
= sinfo
->nr_slots
;
904 while (nr_slots
&& de
>= (struct msdos_dir_entry
*)bh
->b_data
) {
905 de
->name
[0] = DELETED_FLAG
;
909 mark_buffer_dirty(bh
);
911 err
= sync_dirty_buffer(bh
);
919 * Second stage: remove the remaining longname slots.
920 * (This directory entry is already removed, and so return
923 err
= __fat_remove_entries(dir
, sinfo
->slot_off
, nr_slots
);
926 "FAT: Couldn't remove the long name slots\n");
930 dir
->i_mtime
= dir
->i_atime
= CURRENT_TIME_SEC
;
932 (void)fat_sync_inode(dir
);
934 mark_inode_dirty(dir
);
939 EXPORT_SYMBOL_GPL(fat_remove_entries
);
941 static int fat_zeroed_cluster(struct inode
*dir
, sector_t blknr
, int nr_used
,
942 struct buffer_head
**bhs
, int nr_bhs
)
944 struct super_block
*sb
= dir
->i_sb
;
945 sector_t last_blknr
= blknr
+ MSDOS_SB(sb
)->sec_per_clus
;
948 /* Zeroing the unused blocks on this cluster */
951 while (blknr
< last_blknr
) {
952 bhs
[n
] = sb_getblk(sb
, blknr
);
957 memset(bhs
[n
]->b_data
, 0, sb
->s_blocksize
);
958 set_buffer_uptodate(bhs
[n
]);
959 mark_buffer_dirty(bhs
[n
]);
964 if (IS_DIRSYNC(dir
)) {
965 err
= fat_sync_bhs(bhs
, n
);
969 for (i
= 0; i
< n
; i
++)
974 if (IS_DIRSYNC(dir
)) {
975 err
= fat_sync_bhs(bhs
, n
);
979 for (i
= 0; i
< n
; i
++)
985 for (i
= 0; i
< n
; i
++)
990 int fat_alloc_new_dir(struct inode
*dir
, struct timespec
*ts
)
992 struct super_block
*sb
= dir
->i_sb
;
993 struct msdos_sb_info
*sbi
= MSDOS_SB(sb
);
994 struct buffer_head
*bhs
[MAX_BUF_PER_PAGE
];
995 struct msdos_dir_entry
*de
;
1000 err
= fat_alloc_clusters(dir
, &cluster
, 1);
1004 blknr
= fat_clus_to_blknr(sbi
, cluster
);
1005 bhs
[0] = sb_getblk(sb
, blknr
);
1011 fat_date_unix2dos(ts
->tv_sec
, &time
, &date
);
1013 de
= (struct msdos_dir_entry
*)bhs
[0]->b_data
;
1014 /* filling the new directory slots ("." and ".." entries) */
1015 memcpy(de
[0].name
, MSDOS_DOT
, MSDOS_NAME
);
1016 memcpy(de
[1].name
, MSDOS_DOTDOT
, MSDOS_NAME
);
1017 de
->attr
= de
[1].attr
= ATTR_DIR
;
1018 de
[0].lcase
= de
[1].lcase
= 0;
1019 de
[0].time
= de
[1].time
= time
;
1020 de
[0].date
= de
[1].date
= date
;
1021 de
[0].ctime_cs
= de
[1].ctime_cs
= 0;
1022 if (sbi
->options
.isvfat
) {
1023 /* extra timestamps */
1024 de
[0].ctime
= de
[1].ctime
= time
;
1025 de
[0].adate
= de
[0].cdate
= de
[1].adate
= de
[1].cdate
= date
;
1027 de
[0].ctime
= de
[1].ctime
= 0;
1028 de
[0].adate
= de
[0].cdate
= de
[1].adate
= de
[1].cdate
= 0;
1030 de
[0].start
= cpu_to_le16(cluster
);
1031 de
[0].starthi
= cpu_to_le16(cluster
>> 16);
1032 de
[1].start
= cpu_to_le16(MSDOS_I(dir
)->i_logstart
);
1033 de
[1].starthi
= cpu_to_le16(MSDOS_I(dir
)->i_logstart
>> 16);
1034 de
[0].size
= de
[1].size
= 0;
1035 memset(de
+ 2, 0, sb
->s_blocksize
- 2 * sizeof(*de
));
1036 set_buffer_uptodate(bhs
[0]);
1037 mark_buffer_dirty(bhs
[0]);
1039 err
= fat_zeroed_cluster(dir
, blknr
, 1, bhs
, MAX_BUF_PER_PAGE
);
1046 fat_free_clusters(dir
, cluster
);
1051 EXPORT_SYMBOL_GPL(fat_alloc_new_dir
);
1053 static int fat_add_new_entries(struct inode
*dir
, void *slots
, int nr_slots
,
1054 int *nr_cluster
, struct msdos_dir_entry
**de
,
1055 struct buffer_head
**bh
, loff_t
*i_pos
)
1057 struct super_block
*sb
= dir
->i_sb
;
1058 struct msdos_sb_info
*sbi
= MSDOS_SB(sb
);
1059 struct buffer_head
*bhs
[MAX_BUF_PER_PAGE
];
1060 sector_t blknr
, start_blknr
, last_blknr
;
1061 unsigned long size
, copy
;
1062 int err
, i
, n
, offset
, cluster
[2];
1065 * The minimum cluster size is 512bytes, and maximum entry
1066 * size is 32*slots (672bytes). So, iff the cluster size is
1067 * 512bytes, we may need two clusters.
1069 size
= nr_slots
* sizeof(struct msdos_dir_entry
);
1070 *nr_cluster
= (size
+ (sbi
->cluster_size
- 1)) >> sbi
->cluster_bits
;
1071 BUG_ON(*nr_cluster
> 2);
1073 err
= fat_alloc_clusters(dir
, cluster
, *nr_cluster
);
1078 * First stage: Fill the directory entry. NOTE: This cluster
1079 * is not referenced from any inode yet, so updates order is
1084 start_blknr
= blknr
= fat_clus_to_blknr(sbi
, cluster
[i
]);
1085 last_blknr
= start_blknr
+ sbi
->sec_per_clus
;
1086 while (blknr
< last_blknr
) {
1087 bhs
[n
] = sb_getblk(sb
, blknr
);
1093 /* fill the directory entry */
1094 copy
= min(size
, sb
->s_blocksize
);
1095 memcpy(bhs
[n
]->b_data
, slots
, copy
);
1098 set_buffer_uptodate(bhs
[n
]);
1099 mark_buffer_dirty(bhs
[n
]);
1105 } while (++i
< *nr_cluster
);
1107 memset(bhs
[n
]->b_data
+ copy
, 0, sb
->s_blocksize
- copy
);
1108 offset
= copy
- sizeof(struct msdos_dir_entry
);
1111 *de
= (struct msdos_dir_entry
*)((*bh
)->b_data
+ offset
);
1112 *i_pos
= fat_make_i_pos(sb
, *bh
, *de
);
1114 /* Second stage: clear the rest of cluster, and write outs */
1115 err
= fat_zeroed_cluster(dir
, start_blknr
, ++n
, bhs
, MAX_BUF_PER_PAGE
);
1126 for (i
= 0; i
< n
; i
++)
1128 fat_free_clusters(dir
, cluster
[0]);
1133 int fat_add_entries(struct inode
*dir
, void *slots
, int nr_slots
,
1134 struct fat_slot_info
*sinfo
)
1136 struct super_block
*sb
= dir
->i_sb
;
1137 struct msdos_sb_info
*sbi
= MSDOS_SB(sb
);
1138 struct buffer_head
*bh
, *prev
, *bhs
[3]; /* 32*slots (672bytes) */
1139 struct msdos_dir_entry
*de
;
1140 int err
, free_slots
, i
, nr_bhs
;
1143 sinfo
->nr_slots
= nr_slots
;
1145 /* First stage: search free direcotry entries */
1146 free_slots
= nr_bhs
= 0;
1150 while (fat_get_entry(dir
, &pos
, &bh
, &de
) > -1) {
1151 /* check the maximum size of directory */
1152 if (pos
>= FAT_MAX_DIR_SIZE
)
1155 if (IS_FREE(de
->name
)) {
1158 bhs
[nr_bhs
] = prev
= bh
;
1162 if (free_slots
== nr_slots
)
1165 for (i
= 0; i
< nr_bhs
; i
++)
1168 free_slots
= nr_bhs
= 0;
1171 if (dir
->i_ino
== MSDOS_ROOT_INO
) {
1172 if (sbi
->fat_bits
!= 32)
1174 } else if (MSDOS_I(dir
)->i_start
== 0) {
1175 printk(KERN_ERR
"FAT: Corrupted directory (i_pos %lld)\n",
1176 MSDOS_I(dir
)->i_pos
);
1183 pos
-= free_slots
* sizeof(*de
);
1184 nr_slots
-= free_slots
;
1187 * Second stage: filling the free entries with new entries.
1188 * NOTE: If this slots has shortname, first, we write
1189 * the long name slots, then write the short name.
1191 int size
= free_slots
* sizeof(*de
);
1192 int offset
= pos
& (sb
->s_blocksize
- 1);
1193 int long_bhs
= nr_bhs
- (nr_slots
== 0);
1195 /* Fill the long name slots. */
1196 for (i
= 0; i
< long_bhs
; i
++) {
1197 int copy
= min_t(int, sb
->s_blocksize
- offset
, size
);
1198 memcpy(bhs
[i
]->b_data
+ offset
, slots
, copy
);
1199 mark_buffer_dirty(bhs
[i
]);
1204 if (long_bhs
&& IS_DIRSYNC(dir
))
1205 err
= fat_sync_bhs(bhs
, long_bhs
);
1206 if (!err
&& i
< nr_bhs
) {
1207 /* Fill the short name slot. */
1208 int copy
= min_t(int, sb
->s_blocksize
- offset
, size
);
1209 memcpy(bhs
[i
]->b_data
+ offset
, slots
, copy
);
1210 mark_buffer_dirty(bhs
[i
]);
1211 if (IS_DIRSYNC(dir
))
1212 err
= sync_dirty_buffer(bhs
[i
]);
1214 for (i
= 0; i
< nr_bhs
; i
++)
1221 int cluster
, nr_cluster
;
1224 * Third stage: allocate the cluster for new entries.
1225 * And initialize the cluster with new entries, then
1226 * add the cluster to dir.
1228 cluster
= fat_add_new_entries(dir
, slots
, nr_slots
, &nr_cluster
,
1234 err
= fat_chain_add(dir
, cluster
, nr_cluster
);
1236 fat_free_clusters(dir
, cluster
);
1239 if (dir
->i_size
& (sbi
->cluster_size
- 1)) {
1240 fat_fs_panic(sb
, "Odd directory size");
1241 dir
->i_size
= (dir
->i_size
+ sbi
->cluster_size
- 1)
1242 & ~((loff_t
)sbi
->cluster_size
- 1);
1244 dir
->i_size
+= nr_cluster
<< sbi
->cluster_bits
;
1245 MSDOS_I(dir
)->mmu_private
+= nr_cluster
<< sbi
->cluster_bits
;
1247 sinfo
->slot_off
= pos
;
1250 sinfo
->i_pos
= fat_make_i_pos(sb
, sinfo
->bh
, sinfo
->de
);
1256 for (i
= 0; i
< nr_bhs
; i
++)
1263 __fat_remove_entries(dir
, pos
, free_slots
);
1267 EXPORT_SYMBOL_GPL(fat_add_entries
);