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/buffer_head.h>
20 #include <linux/compat.h>
21 #include <asm/uaccess.h>
22 #include <linux/kernel.h>
26 * Maximum buffer size of short name.
27 * [(MSDOS_NAME + '.') * max one char + nul]
28 * For msdos style, ['.' (hidden) + MSDOS_NAME + '.' + nul]
30 #define FAT_MAX_SHORT_SIZE ((MSDOS_NAME + 1) * NLS_MAX_CHARSET_SIZE + 1)
32 * Maximum buffer size of unicode chars from slots.
33 * [(max longname slots * 13 (size in a slot) + nul) * sizeof(wchar_t)]
35 #define FAT_MAX_UNI_CHARS ((MSDOS_SLOTS - 1) * 13 + 1)
36 #define FAT_MAX_UNI_SIZE (FAT_MAX_UNI_CHARS * sizeof(wchar_t))
38 static inline loff_t fat_make_i_pos(struct super_block *sb,
39 struct buffer_head *bh,
40 struct msdos_dir_entry *de)
42 return ((loff_t)bh->b_blocknr << MSDOS_SB(sb)->dir_per_block_bits)
43 | (de - (struct msdos_dir_entry *)bh->b_data);
46 static inline void fat_dir_readahead(struct inode *dir, sector_t iblock,
49 struct super_block *sb = dir->i_sb;
50 struct msdos_sb_info *sbi = MSDOS_SB(sb);
51 struct buffer_head *bh;
54 /* This is not a first sector of cluster, or sec_per_clus == 1 */
55 if ((iblock & (sbi->sec_per_clus - 1)) || sbi->sec_per_clus == 1)
57 /* root dir of FAT12/FAT16 */
58 if ((sbi->fat_bits != 32) && (dir->i_ino == MSDOS_ROOT_INO))
61 bh = sb_find_get_block(sb, phys);
62 if (bh == NULL || !buffer_uptodate(bh)) {
63 for (sec = 0; sec < sbi->sec_per_clus; sec++)
64 sb_breadahead(sb, phys + sec);
69 /* Returns the inode number of the directory entry at offset pos. If bh is
70 non-NULL, it is brelse'd before. Pos is incremented. The buffer header is
72 AV. Most often we do it item-by-item. Makes sense to optimize.
73 AV. OK, there we go: if both bh and de are non-NULL we assume that we just
74 AV. want the next entry (took one explicit de=NULL in vfat/namei.c).
75 AV. It's done in fat_get_entry() (inlined), here the slow case lives.
76 AV. Additionally, when we return -1 (i.e. reached the end of directory)
79 static int fat__get_entry(struct inode *dir, loff_t *pos,
80 struct buffer_head **bh, struct msdos_dir_entry **de)
82 struct super_block *sb = dir->i_sb;
83 sector_t phys, iblock;
84 unsigned long mapped_blocks;
92 iblock = *pos >> sb->s_blocksize_bits;
93 err = fat_bmap(dir, iblock, &phys, &mapped_blocks, 0);
95 return -1; /* beyond EOF or error */
97 fat_dir_readahead(dir, iblock, phys);
99 *bh = sb_bread(sb, phys);
101 fat_msg(sb, KERN_ERR, "Directory bread(block %llu) failed",
103 /* skip this block */
104 *pos = (iblock + 1) << sb->s_blocksize_bits;
108 offset = *pos & (sb->s_blocksize - 1);
109 *pos += sizeof(struct msdos_dir_entry);
110 *de = (struct msdos_dir_entry *)((*bh)->b_data + offset);
115 static inline int fat_get_entry(struct inode *dir, loff_t *pos,
116 struct buffer_head **bh,
117 struct msdos_dir_entry **de)
119 /* Fast stuff first */
121 (*de - (struct msdos_dir_entry *)(*bh)->b_data) < MSDOS_SB(dir->i_sb)->dir_per_block - 1) {
122 *pos += sizeof(struct msdos_dir_entry);
126 return fat__get_entry(dir, pos, bh, de);
130 * Convert Unicode 16 to UTF-8, translated Unicode, or ASCII.
131 * If uni_xlate is enabled and we can't get a 1:1 conversion, use a
132 * colon as an escape character since it is normally invalid on the vfat
133 * filesystem. The following four characters are the hexadecimal digits
134 * of Unicode value. This lets us do a full dump and restore of Unicode
135 * filenames. We could get into some trouble with long Unicode names,
136 * but ignore that right now.
137 * Ahem... Stack smashing in ring 0 isn't fun. Fixed.
139 static int uni16_to_x8(struct super_block *sb, unsigned char *ascii,
140 const wchar_t *uni, int len, struct nls_table *nls)
142 int uni_xlate = MSDOS_SB(sb)->options.unicode_xlate;
151 while (*ip && ((len - NLS_MAX_CHARSET_SIZE) > 0)) {
153 if ((charlen = nls->uni2char(ec, op, NLS_MAX_CHARSET_SIZE)) > 0) {
157 if (uni_xlate == 1) {
159 op = hex_byte_pack(op, ec >> 8);
160 op = hex_byte_pack(op, ec);
170 fat_msg(sb, KERN_WARNING, "filename was truncated while "
178 static inline int fat_uni_to_x8(struct super_block *sb, const wchar_t *uni,
179 unsigned char *buf, int size)
181 struct msdos_sb_info *sbi = MSDOS_SB(sb);
182 if (sbi->options.utf8)
183 return utf16s_to_utf8s(uni, FAT_MAX_UNI_CHARS,
184 UTF16_HOST_ENDIAN, buf, size);
186 return uni16_to_x8(sb, buf, uni, size, sbi->nls_io);
190 fat_short2uni(struct nls_table *t, unsigned char *c, int clen, wchar_t *uni)
194 charlen = t->char2uni(c, clen, uni);
196 *uni = 0x003f; /* a question mark */
203 fat_short2lower_uni(struct nls_table *t, unsigned char *c, int clen, wchar_t *uni)
208 charlen = t->char2uni(c, clen, &wc);
210 *uni = 0x003f; /* a question mark */
212 } else if (charlen <= 1) {
213 unsigned char nc = t->charset2lower[*c];
218 if ( (charlen = t->char2uni(&nc, 1, uni)) < 0) {
219 *uni = 0x003f; /* a question mark */
229 fat_shortname2uni(struct nls_table *nls, unsigned char *buf, int buf_size,
230 wchar_t *uni_buf, unsigned short opt, int lower)
234 if (opt & VFAT_SFN_DISPLAY_LOWER)
235 len = fat_short2lower_uni(nls, buf, buf_size, uni_buf);
236 else if (opt & VFAT_SFN_DISPLAY_WIN95)
237 len = fat_short2uni(nls, buf, buf_size, uni_buf);
238 else if (opt & VFAT_SFN_DISPLAY_WINNT) {
240 len = fat_short2lower_uni(nls, buf, buf_size, uni_buf);
242 len = fat_short2uni(nls, buf, buf_size, uni_buf);
244 len = fat_short2uni(nls, buf, buf_size, uni_buf);
249 static inline int fat_name_match(struct msdos_sb_info *sbi,
250 const unsigned char *a, int a_len,
251 const unsigned char *b, int b_len)
256 if (sbi->options.name_check != 's')
257 return !nls_strnicmp(sbi->nls_io, a, b, a_len);
259 return !memcmp(a, b, a_len);
262 enum { PARSE_INVALID = 1, PARSE_NOT_LONGNAME, PARSE_EOF, };
265 * fat_parse_long - Parse extended directory entry.
267 * This function returns zero on success, negative value on error, or one of
270 * %PARSE_INVALID - Directory entry is invalid.
271 * %PARSE_NOT_LONGNAME - Directory entry does not contain longname.
272 * %PARSE_EOF - Directory has no more entries.
274 static int fat_parse_long(struct inode *dir, loff_t *pos,
275 struct buffer_head **bh, struct msdos_dir_entry **de,
276 wchar_t **unicode, unsigned char *nr_slots)
278 struct msdos_dir_slot *ds;
279 unsigned char id, slot, slots, alias_checksum;
282 *unicode = __getname();
290 ds = (struct msdos_dir_slot *)*de;
293 return PARSE_INVALID;
295 if (slots > 20 || !slots) /* ceil(256 * 2 / 26) */
296 return PARSE_INVALID;
298 alias_checksum = ds->alias_checksum;
306 fat16_towchar(*unicode + offset, ds->name0_4, 5);
307 fat16_towchar(*unicode + offset + 5, ds->name5_10, 6);
308 fat16_towchar(*unicode + offset + 11, ds->name11_12, 2);
311 (*unicode)[offset + 13] = 0;
312 if (fat_get_entry(dir, pos, bh, de) < 0)
316 ds = (struct msdos_dir_slot *)*de;
317 if (ds->attr != ATTR_EXT)
318 return PARSE_NOT_LONGNAME;
319 if ((ds->id & ~0x40) != slot)
321 if (ds->alias_checksum != alias_checksum)
324 if ((*de)->name[0] == DELETED_FLAG)
325 return PARSE_INVALID;
326 if ((*de)->attr == ATTR_EXT)
328 if (IS_FREE((*de)->name) || ((*de)->attr & ATTR_VOLUME))
329 return PARSE_INVALID;
330 if (fat_checksum((*de)->name) != alias_checksum)
337 * Return values: negative -> error, 0 -> not found, positive -> found,
338 * value is the total amount of slots, including the shortname entry.
340 int fat_search_long(struct inode *inode, const unsigned char *name,
341 int name_len, struct fat_slot_info *sinfo)
343 struct super_block *sb = inode->i_sb;
344 struct msdos_sb_info *sbi = MSDOS_SB(sb);
345 struct buffer_head *bh = NULL;
346 struct msdos_dir_entry *de;
347 struct nls_table *nls_disk = sbi->nls_disk;
348 unsigned char nr_slots;
349 wchar_t bufuname[14];
350 wchar_t *unicode = NULL;
351 unsigned char work[MSDOS_NAME];
352 unsigned char bufname[FAT_MAX_SHORT_SIZE];
353 unsigned short opt_shortname = sbi->options.shortname;
355 int chl, i, j, last_u, err, len;
359 if (fat_get_entry(inode, &cpos, &bh, &de) == -1)
363 if (de->name[0] == DELETED_FLAG)
365 if (de->attr != ATTR_EXT && (de->attr & ATTR_VOLUME))
367 if (de->attr != ATTR_EXT && IS_FREE(de->name))
369 if (de->attr == ATTR_EXT) {
370 int status = fat_parse_long(inode, &cpos, &bh, &de,
371 &unicode, &nr_slots);
375 } else if (status == PARSE_INVALID)
377 else if (status == PARSE_NOT_LONGNAME)
379 else if (status == PARSE_EOF)
383 memcpy(work, de->name, sizeof(de->name));
384 /* see namei.c, msdos_format_name */
387 for (i = 0, j = 0, last_u = 0; i < 8;) {
390 chl = fat_shortname2uni(nls_disk, &work[i], 8 - i,
391 &bufuname[j++], opt_shortname,
392 de->lcase & CASE_LOWER_BASE);
402 fat_short2uni(nls_disk, ".", 1, &bufuname[j++]);
403 for (i = 8; i < MSDOS_NAME;) {
406 chl = fat_shortname2uni(nls_disk, &work[i],
408 &bufuname[j++], opt_shortname,
409 de->lcase & CASE_LOWER_EXT);
421 /* Compare shortname */
422 bufuname[last_u] = 0x0000;
423 len = fat_uni_to_x8(sb, bufuname, bufname, sizeof(bufname));
424 if (fat_name_match(sbi, name, name_len, bufname, len))
428 void *longname = unicode + FAT_MAX_UNI_CHARS;
429 int size = PATH_MAX - FAT_MAX_UNI_SIZE;
431 /* Compare longname */
432 len = fat_uni_to_x8(sb, unicode, longname, size);
433 if (fat_name_match(sbi, name, name_len, longname, len))
439 nr_slots++; /* include the de */
440 sinfo->slot_off = cpos - nr_slots * sizeof(*de);
441 sinfo->nr_slots = nr_slots;
444 sinfo->i_pos = fat_make_i_pos(sb, sinfo->bh, sinfo->de);
453 EXPORT_SYMBOL_GPL(fat_search_long);
455 struct fat_ioctl_filldir_callback {
459 const char *longname;
461 const char *shortname;
465 static int __fat_readdir(struct inode *inode, struct file *filp, void *dirent,
466 filldir_t filldir, int short_only, int both)
468 struct super_block *sb = inode->i_sb;
469 struct msdos_sb_info *sbi = MSDOS_SB(sb);
470 struct buffer_head *bh;
471 struct msdos_dir_entry *de;
472 struct nls_table *nls_disk = sbi->nls_disk;
473 unsigned char nr_slots;
474 wchar_t bufuname[14];
475 wchar_t *unicode = NULL;
476 unsigned char c, work[MSDOS_NAME];
477 unsigned char bufname[FAT_MAX_SHORT_SIZE], *ptname = bufname;
478 unsigned short opt_shortname = sbi->options.shortname;
479 int isvfat = sbi->options.isvfat;
480 int nocase = sbi->options.nocase;
481 const char *fill_name = NULL;
483 unsigned long lpos, dummy, *furrfu = &lpos;
485 int chi, chl, i, i2, j, last, last_u, dotoffset = 0, fill_len = 0;
491 /* Fake . and .. for the root directory. */
492 if (inode->i_ino == MSDOS_ROOT_INO) {
494 if (filldir(dirent, "..", cpos+1, cpos, MSDOS_ROOT_INO, DT_DIR) < 0)
505 if (cpos & (sizeof(struct msdos_dir_entry) - 1)) {
512 if (fat_get_entry(inode, &cpos, &bh, &de) == -1)
517 * Check for long filename entry, but if short_only, we don't
518 * need to parse long filename.
520 if (isvfat && !short_only) {
521 if (de->name[0] == DELETED_FLAG)
523 if (de->attr != ATTR_EXT && (de->attr & ATTR_VOLUME))
525 if (de->attr != ATTR_EXT && IS_FREE(de->name))
528 if ((de->attr & ATTR_VOLUME) || IS_FREE(de->name))
532 if (isvfat && de->attr == ATTR_EXT) {
533 int status = fat_parse_long(inode, &cpos, &bh, &de,
534 &unicode, &nr_slots);
539 } else if (status == PARSE_INVALID)
541 else if (status == PARSE_NOT_LONGNAME)
543 else if (status == PARSE_EOF)
547 void *longname = unicode + FAT_MAX_UNI_CHARS;
548 int size = PATH_MAX - FAT_MAX_UNI_SIZE;
549 int len = fat_uni_to_x8(sb, unicode, longname, size);
551 fill_name = longname;
553 /* !both && !short_only, so we don't need shortname. */
559 if (sbi->options.dotsOK) {
562 if (de->attr & ATTR_HIDDEN) {
568 memcpy(work, de->name, sizeof(de->name));
569 /* see namei.c, msdos_format_name */
572 for (i = 0, j = 0, last = 0, last_u = 0; i < 8;) {
575 chl = fat_shortname2uni(nls_disk, &work[i], 8 - i,
576 &bufuname[j++], opt_shortname,
577 de->lcase & CASE_LOWER_BASE);
579 ptname[i++] = (!nocase && c>='A' && c<='Z') ? c+32 : c;
586 for (chi = 0; chi < chl && i < 8; chi++) {
594 fat_short2uni(nls_disk, ".", 1, &bufuname[j++]);
596 for (i2 = 8; i2 < MSDOS_NAME;) {
599 chl = fat_shortname2uni(nls_disk, &work[i2], MSDOS_NAME - i2,
600 &bufuname[j++], opt_shortname,
601 de->lcase & CASE_LOWER_EXT);
604 ptname[i++] = (!nocase && c>='A' && c<='Z') ? c+32 : c;
611 for (chi = 0; chi < chl && i2 < MSDOS_NAME; chi++) {
612 ptname[i++] = work[i2++];
620 i = last + dotoffset;
624 bufuname[j] = 0x0000;
625 i = fat_uni_to_x8(sb, bufuname, bufname, sizeof(bufname));
628 /* hack for fat_ioctl_filldir() */
629 struct fat_ioctl_filldir_callback *p = dirent;
631 p->longname = fill_name;
632 p->long_len = fill_len;
633 p->shortname = bufname;
643 lpos = cpos - (nr_slots + 1) * sizeof(struct msdos_dir_entry);
644 if (!memcmp(de->name, MSDOS_DOT, MSDOS_NAME))
646 else if (!memcmp(de->name, MSDOS_DOTDOT, MSDOS_NAME)) {
647 inum = parent_ino(filp->f_path.dentry);
649 loff_t i_pos = fat_make_i_pos(sb, bh, de);
650 struct inode *tmp = fat_iget(sb, i_pos);
655 inum = iunique(sb, MSDOS_ROOT_INO);
658 if (filldir(dirent, fill_name, fill_len, *furrfu, inum,
659 (de->attr & ATTR_DIR) ? DT_DIR : DT_REG) < 0)
677 static int fat_readdir(struct file *filp, void *dirent, filldir_t filldir)
679 struct inode *inode = filp->f_path.dentry->d_inode;
680 return __fat_readdir(inode, filp, dirent, filldir, 0, 0);
683 #define FAT_IOCTL_FILLDIR_FUNC(func, dirent_type) \
684 static int func(void *__buf, const char *name, int name_len, \
685 loff_t offset, u64 ino, unsigned int d_type) \
687 struct fat_ioctl_filldir_callback *buf = __buf; \
688 struct dirent_type __user *d1 = buf->dirent; \
689 struct dirent_type __user *d2 = d1 + 1; \
695 if (name != NULL) { \
696 /* dirent has only short name */ \
697 if (name_len >= sizeof(d1->d_name)) \
698 name_len = sizeof(d1->d_name) - 1; \
700 if (put_user(0, d2->d_name) || \
701 put_user(0, &d2->d_reclen) || \
702 copy_to_user(d1->d_name, name, name_len) || \
703 put_user(0, d1->d_name + name_len) || \
704 put_user(name_len, &d1->d_reclen)) \
707 /* dirent has short and long name */ \
708 const char *longname = buf->longname; \
709 int long_len = buf->long_len; \
710 const char *shortname = buf->shortname; \
711 int short_len = buf->short_len; \
713 if (long_len >= sizeof(d1->d_name)) \
714 long_len = sizeof(d1->d_name) - 1; \
715 if (short_len >= sizeof(d1->d_name)) \
716 short_len = sizeof(d1->d_name) - 1; \
718 if (copy_to_user(d2->d_name, longname, long_len) || \
719 put_user(0, d2->d_name + long_len) || \
720 put_user(long_len, &d2->d_reclen) || \
721 put_user(ino, &d2->d_ino) || \
722 put_user(offset, &d2->d_off) || \
723 copy_to_user(d1->d_name, shortname, short_len) || \
724 put_user(0, d1->d_name + short_len) || \
725 put_user(short_len, &d1->d_reclen)) \
730 buf->result = -EFAULT; \
734 FAT_IOCTL_FILLDIR_FUNC(fat_ioctl_filldir, __fat_dirent)
736 static int fat_ioctl_readdir(struct inode *inode, struct file *filp,
737 void __user *dirent, filldir_t filldir,
738 int short_only, int both)
740 struct fat_ioctl_filldir_callback buf;
745 mutex_lock(&inode->i_mutex);
747 if (!IS_DEADDIR(inode)) {
748 ret = __fat_readdir(inode, filp, &buf, filldir,
751 mutex_unlock(&inode->i_mutex);
757 static int fat_ioctl_volume_id(struct inode *dir)
759 struct super_block *sb = dir->i_sb;
760 struct msdos_sb_info *sbi = MSDOS_SB(sb);
764 static long fat_dir_ioctl(struct file *filp, unsigned int cmd,
767 struct inode *inode = filp->f_path.dentry->d_inode;
768 struct __fat_dirent __user *d1 = (struct __fat_dirent __user *)arg;
769 int short_only, both;
772 case VFAT_IOCTL_READDIR_SHORT:
776 case VFAT_IOCTL_READDIR_BOTH:
780 case VFAT_IOCTL_GET_VOLUME_ID:
781 return fat_ioctl_volume_id(inode);
783 return fat_generic_ioctl(filp, cmd, arg);
786 if (!access_ok(VERIFY_WRITE, d1, sizeof(struct __fat_dirent[2])))
789 * Yes, we don't need this put_user() absolutely. However old
790 * code didn't return the right value. So, app use this value,
791 * in order to check whether it is EOF.
793 if (put_user(0, &d1->d_reclen))
796 return fat_ioctl_readdir(inode, filp, d1, fat_ioctl_filldir,
801 #define VFAT_IOCTL_READDIR_BOTH32 _IOR('r', 1, struct compat_dirent[2])
802 #define VFAT_IOCTL_READDIR_SHORT32 _IOR('r', 2, struct compat_dirent[2])
804 FAT_IOCTL_FILLDIR_FUNC(fat_compat_ioctl_filldir, compat_dirent)
806 static long fat_compat_dir_ioctl(struct file *filp, unsigned cmd,
809 struct inode *inode = filp->f_path.dentry->d_inode;
810 struct compat_dirent __user *d1 = compat_ptr(arg);
811 int short_only, both;
814 case VFAT_IOCTL_READDIR_SHORT32:
818 case VFAT_IOCTL_READDIR_BOTH32:
823 return fat_generic_ioctl(filp, cmd, (unsigned long)arg);
826 if (!access_ok(VERIFY_WRITE, d1, sizeof(struct compat_dirent[2])))
829 * Yes, we don't need this put_user() absolutely. However old
830 * code didn't return the right value. So, app use this value,
831 * in order to check whether it is EOF.
833 if (put_user(0, &d1->d_reclen))
836 return fat_ioctl_readdir(inode, filp, d1, fat_compat_ioctl_filldir,
839 #endif /* CONFIG_COMPAT */
841 const struct file_operations fat_dir_operations = {
842 .llseek = generic_file_llseek,
843 .read = generic_read_dir,
844 .readdir = fat_readdir,
845 .unlocked_ioctl = fat_dir_ioctl,
847 .compat_ioctl = fat_compat_dir_ioctl,
849 .fsync = fat_file_fsync,
852 static int fat_get_short_entry(struct inode *dir, loff_t *pos,
853 struct buffer_head **bh,
854 struct msdos_dir_entry **de)
856 while (fat_get_entry(dir, pos, bh, de) >= 0) {
857 /* free entry or long name entry or volume label */
858 if (!IS_FREE((*de)->name) && !((*de)->attr & ATTR_VOLUME))
865 * The ".." entry can not provide the "struct fat_slot_info" informations
866 * for inode. So, this function provide the some informations only.
868 int fat_get_dotdot_entry(struct inode *dir, struct buffer_head **bh,
869 struct msdos_dir_entry **de, loff_t *i_pos)
875 while (fat_get_short_entry(dir, &offset, bh, de) >= 0) {
876 if (!strncmp((*de)->name, MSDOS_DOTDOT, MSDOS_NAME)) {
877 *i_pos = fat_make_i_pos(dir->i_sb, *bh, *de);
884 EXPORT_SYMBOL_GPL(fat_get_dotdot_entry);
886 /* See if directory is empty */
887 int fat_dir_empty(struct inode *dir)
889 struct buffer_head *bh;
890 struct msdos_dir_entry *de;
896 while (fat_get_short_entry(dir, &cpos, &bh, &de) >= 0) {
897 if (strncmp(de->name, MSDOS_DOT , MSDOS_NAME) &&
898 strncmp(de->name, MSDOS_DOTDOT, MSDOS_NAME)) {
907 EXPORT_SYMBOL_GPL(fat_dir_empty);
910 * fat_subdirs counts the number of sub-directories of dir. It can be run
911 * on directories being created.
913 int fat_subdirs(struct inode *dir)
915 struct buffer_head *bh;
916 struct msdos_dir_entry *de;
922 while (fat_get_short_entry(dir, &cpos, &bh, &de) >= 0) {
923 if (de->attr & ATTR_DIR)
931 * Scans a directory for a given file (name points to its formatted name).
932 * Returns an error code or zero.
934 int fat_scan(struct inode *dir, const unsigned char *name,
935 struct fat_slot_info *sinfo)
937 struct super_block *sb = dir->i_sb;
941 while (fat_get_short_entry(dir, &sinfo->slot_off, &sinfo->bh,
943 if (!strncmp(sinfo->de->name, name, MSDOS_NAME)) {
944 sinfo->slot_off -= sizeof(*sinfo->de);
946 sinfo->i_pos = fat_make_i_pos(sb, sinfo->bh, sinfo->de);
953 EXPORT_SYMBOL_GPL(fat_scan);
955 static int __fat_remove_entries(struct inode *dir, loff_t pos, int nr_slots)
957 struct super_block *sb = dir->i_sb;
958 struct buffer_head *bh;
959 struct msdos_dir_entry *de, *endp;
960 int err = 0, orig_slots;
964 if (fat_get_entry(dir, &pos, &bh, &de) < 0) {
969 orig_slots = nr_slots;
970 endp = (struct msdos_dir_entry *)(bh->b_data + sb->s_blocksize);
971 while (nr_slots && de < endp) {
972 de->name[0] = DELETED_FLAG;
976 mark_buffer_dirty_inode(bh, dir);
978 err = sync_dirty_buffer(bh);
983 /* pos is *next* de's position, so this does `- sizeof(de)' */
984 pos += ((orig_slots - nr_slots) * sizeof(*de)) - sizeof(*de);
990 int fat_remove_entries(struct inode *dir, struct fat_slot_info *sinfo)
992 struct super_block *sb = dir->i_sb;
993 struct msdos_dir_entry *de;
994 struct buffer_head *bh;
995 int err = 0, nr_slots;
998 * First stage: Remove the shortname. By this, the directory
1001 nr_slots = sinfo->nr_slots;
1006 while (nr_slots && de >= (struct msdos_dir_entry *)bh->b_data) {
1007 de->name[0] = DELETED_FLAG;
1011 mark_buffer_dirty_inode(bh, dir);
1012 if (IS_DIRSYNC(dir))
1013 err = sync_dirty_buffer(bh);
1021 * Second stage: remove the remaining longname slots.
1022 * (This directory entry is already removed, and so return
1025 err = __fat_remove_entries(dir, sinfo->slot_off, nr_slots);
1027 fat_msg(sb, KERN_WARNING,
1028 "Couldn't remove the long name slots");
1032 dir->i_mtime = dir->i_atime = CURRENT_TIME_SEC;
1033 if (IS_DIRSYNC(dir))
1034 (void)fat_sync_inode(dir);
1036 mark_inode_dirty(dir);
1041 EXPORT_SYMBOL_GPL(fat_remove_entries);
1043 static int fat_zeroed_cluster(struct inode *dir, sector_t blknr, int nr_used,
1044 struct buffer_head **bhs, int nr_bhs)
1046 struct super_block *sb = dir->i_sb;
1047 sector_t last_blknr = blknr + MSDOS_SB(sb)->sec_per_clus;
1050 /* Zeroing the unused blocks on this cluster */
1053 while (blknr < last_blknr) {
1054 bhs[n] = sb_getblk(sb, blknr);
1059 memset(bhs[n]->b_data, 0, sb->s_blocksize);
1060 set_buffer_uptodate(bhs[n]);
1061 mark_buffer_dirty_inode(bhs[n], dir);
1066 if (IS_DIRSYNC(dir)) {
1067 err = fat_sync_bhs(bhs, n);
1071 for (i = 0; i < n; i++)
1076 if (IS_DIRSYNC(dir)) {
1077 err = fat_sync_bhs(bhs, n);
1081 for (i = 0; i < n; i++)
1087 for (i = 0; i < n; i++)
1092 int fat_alloc_new_dir(struct inode *dir, struct timespec *ts)
1094 struct super_block *sb = dir->i_sb;
1095 struct msdos_sb_info *sbi = MSDOS_SB(sb);
1096 struct buffer_head *bhs[MAX_BUF_PER_PAGE];
1097 struct msdos_dir_entry *de;
1103 err = fat_alloc_clusters(dir, &cluster, 1);
1107 blknr = fat_clus_to_blknr(sbi, cluster);
1108 bhs[0] = sb_getblk(sb, blknr);
1114 fat_time_unix2fat(sbi, ts, &time, &date, &time_cs);
1116 de = (struct msdos_dir_entry *)bhs[0]->b_data;
1117 /* filling the new directory slots ("." and ".." entries) */
1118 memcpy(de[0].name, MSDOS_DOT, MSDOS_NAME);
1119 memcpy(de[1].name, MSDOS_DOTDOT, MSDOS_NAME);
1120 de->attr = de[1].attr = ATTR_DIR;
1121 de[0].lcase = de[1].lcase = 0;
1122 de[0].time = de[1].time = time;
1123 de[0].date = de[1].date = date;
1124 if (sbi->options.isvfat) {
1125 /* extra timestamps */
1126 de[0].ctime = de[1].ctime = time;
1127 de[0].ctime_cs = de[1].ctime_cs = time_cs;
1128 de[0].adate = de[0].cdate = de[1].adate = de[1].cdate = date;
1130 de[0].ctime = de[1].ctime = 0;
1131 de[0].ctime_cs = de[1].ctime_cs = 0;
1132 de[0].adate = de[0].cdate = de[1].adate = de[1].cdate = 0;
1134 de[0].start = cpu_to_le16(cluster);
1135 de[0].starthi = cpu_to_le16(cluster >> 16);
1136 de[1].start = cpu_to_le16(MSDOS_I(dir)->i_logstart);
1137 de[1].starthi = cpu_to_le16(MSDOS_I(dir)->i_logstart >> 16);
1138 de[0].size = de[1].size = 0;
1139 memset(de + 2, 0, sb->s_blocksize - 2 * sizeof(*de));
1140 set_buffer_uptodate(bhs[0]);
1141 mark_buffer_dirty_inode(bhs[0], dir);
1143 err = fat_zeroed_cluster(dir, blknr, 1, bhs, MAX_BUF_PER_PAGE);
1150 fat_free_clusters(dir, cluster);
1155 EXPORT_SYMBOL_GPL(fat_alloc_new_dir);
1157 static int fat_add_new_entries(struct inode *dir, void *slots, int nr_slots,
1158 int *nr_cluster, struct msdos_dir_entry **de,
1159 struct buffer_head **bh, loff_t *i_pos)
1161 struct super_block *sb = dir->i_sb;
1162 struct msdos_sb_info *sbi = MSDOS_SB(sb);
1163 struct buffer_head *bhs[MAX_BUF_PER_PAGE];
1164 sector_t blknr, start_blknr, last_blknr;
1165 unsigned long size, copy;
1166 int err, i, n, offset, cluster[2];
1169 * The minimum cluster size is 512bytes, and maximum entry
1170 * size is 32*slots (672bytes). So, iff the cluster size is
1171 * 512bytes, we may need two clusters.
1173 size = nr_slots * sizeof(struct msdos_dir_entry);
1174 *nr_cluster = (size + (sbi->cluster_size - 1)) >> sbi->cluster_bits;
1175 BUG_ON(*nr_cluster > 2);
1177 err = fat_alloc_clusters(dir, cluster, *nr_cluster);
1182 * First stage: Fill the directory entry. NOTE: This cluster
1183 * is not referenced from any inode yet, so updates order is
1188 start_blknr = blknr = fat_clus_to_blknr(sbi, cluster[i]);
1189 last_blknr = start_blknr + sbi->sec_per_clus;
1190 while (blknr < last_blknr) {
1191 bhs[n] = sb_getblk(sb, blknr);
1197 /* fill the directory entry */
1198 copy = min(size, sb->s_blocksize);
1199 memcpy(bhs[n]->b_data, slots, copy);
1202 set_buffer_uptodate(bhs[n]);
1203 mark_buffer_dirty_inode(bhs[n], dir);
1209 } while (++i < *nr_cluster);
1211 memset(bhs[n]->b_data + copy, 0, sb->s_blocksize - copy);
1212 offset = copy - sizeof(struct msdos_dir_entry);
1215 *de = (struct msdos_dir_entry *)((*bh)->b_data + offset);
1216 *i_pos = fat_make_i_pos(sb, *bh, *de);
1218 /* Second stage: clear the rest of cluster, and write outs */
1219 err = fat_zeroed_cluster(dir, start_blknr, ++n, bhs, MAX_BUF_PER_PAGE);
1230 for (i = 0; i < n; i++)
1232 fat_free_clusters(dir, cluster[0]);
1237 int fat_add_entries(struct inode *dir, void *slots, int nr_slots,
1238 struct fat_slot_info *sinfo)
1240 struct super_block *sb = dir->i_sb;
1241 struct msdos_sb_info *sbi = MSDOS_SB(sb);
1242 struct buffer_head *bh, *prev, *bhs[3]; /* 32*slots (672bytes) */
1243 struct msdos_dir_entry *uninitialized_var(de);
1244 int err, free_slots, i, nr_bhs;
1247 sinfo->nr_slots = nr_slots;
1249 /* First stage: search free direcotry entries */
1250 free_slots = nr_bhs = 0;
1254 while (fat_get_entry(dir, &pos, &bh, &de) > -1) {
1255 /* check the maximum size of directory */
1256 if (pos >= FAT_MAX_DIR_SIZE)
1259 if (IS_FREE(de->name)) {
1262 bhs[nr_bhs] = prev = bh;
1266 if (free_slots == nr_slots)
1269 for (i = 0; i < nr_bhs; i++)
1272 free_slots = nr_bhs = 0;
1275 if (dir->i_ino == MSDOS_ROOT_INO) {
1276 if (sbi->fat_bits != 32)
1278 } else if (MSDOS_I(dir)->i_start == 0) {
1279 fat_msg(sb, KERN_ERR, "Corrupted directory (i_pos %lld)",
1280 MSDOS_I(dir)->i_pos);
1287 pos -= free_slots * sizeof(*de);
1288 nr_slots -= free_slots;
1291 * Second stage: filling the free entries with new entries.
1292 * NOTE: If this slots has shortname, first, we write
1293 * the long name slots, then write the short name.
1295 int size = free_slots * sizeof(*de);
1296 int offset = pos & (sb->s_blocksize - 1);
1297 int long_bhs = nr_bhs - (nr_slots == 0);
1299 /* Fill the long name slots. */
1300 for (i = 0; i < long_bhs; i++) {
1301 int copy = min_t(int, sb->s_blocksize - offset, size);
1302 memcpy(bhs[i]->b_data + offset, slots, copy);
1303 mark_buffer_dirty_inode(bhs[i], dir);
1308 if (long_bhs && IS_DIRSYNC(dir))
1309 err = fat_sync_bhs(bhs, long_bhs);
1310 if (!err && i < nr_bhs) {
1311 /* Fill the short name slot. */
1312 int copy = min_t(int, sb->s_blocksize - offset, size);
1313 memcpy(bhs[i]->b_data + offset, slots, copy);
1314 mark_buffer_dirty_inode(bhs[i], dir);
1315 if (IS_DIRSYNC(dir))
1316 err = sync_dirty_buffer(bhs[i]);
1318 for (i = 0; i < nr_bhs; i++)
1325 int cluster, nr_cluster;
1328 * Third stage: allocate the cluster for new entries.
1329 * And initialize the cluster with new entries, then
1330 * add the cluster to dir.
1332 cluster = fat_add_new_entries(dir, slots, nr_slots, &nr_cluster,
1338 err = fat_chain_add(dir, cluster, nr_cluster);
1340 fat_free_clusters(dir, cluster);
1343 if (dir->i_size & (sbi->cluster_size - 1)) {
1344 fat_fs_error(sb, "Odd directory size");
1345 dir->i_size = (dir->i_size + sbi->cluster_size - 1)
1346 & ~((loff_t)sbi->cluster_size - 1);
1348 dir->i_size += nr_cluster << sbi->cluster_bits;
1349 MSDOS_I(dir)->mmu_private += nr_cluster << sbi->cluster_bits;
1351 sinfo->slot_off = pos;
1354 sinfo->i_pos = fat_make_i_pos(sb, sinfo->bh, sinfo->de);
1360 for (i = 0; i < nr_bhs; i++)
1367 __fat_remove_entries(dir, pos, free_slots);
1371 EXPORT_SYMBOL_GPL(fat_add_entries);