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 <linux/compat.h>
24 #include <asm/uaccess.h>
26 static inline loff_t fat_make_i_pos(struct super_block *sb,
27 struct buffer_head *bh,
28 struct msdos_dir_entry *de)
30 return ((loff_t)bh->b_blocknr << MSDOS_SB(sb)->dir_per_block_bits)
31 | (de - (struct msdos_dir_entry *)bh->b_data);
34 static inline void fat_dir_readahead(struct inode *dir, sector_t iblock,
37 struct super_block *sb = dir->i_sb;
38 struct msdos_sb_info *sbi = MSDOS_SB(sb);
39 struct buffer_head *bh;
42 /* This is not a first sector of cluster, or sec_per_clus == 1 */
43 if ((iblock & (sbi->sec_per_clus - 1)) || sbi->sec_per_clus == 1)
45 /* root dir of FAT12/FAT16 */
46 if ((sbi->fat_bits != 32) && (dir->i_ino == MSDOS_ROOT_INO))
49 bh = sb_find_get_block(sb, phys);
50 if (bh == NULL || !buffer_uptodate(bh)) {
51 for (sec = 0; sec < sbi->sec_per_clus; sec++)
52 sb_breadahead(sb, phys + sec);
57 /* Returns the inode number of the directory entry at offset pos. If bh is
58 non-NULL, it is brelse'd before. Pos is incremented. The buffer header is
60 AV. Most often we do it item-by-item. Makes sense to optimize.
61 AV. OK, there we go: if both bh and de are non-NULL we assume that we just
62 AV. want the next entry (took one explicit de=NULL in vfat/namei.c).
63 AV. It's done in fat_get_entry() (inlined), here the slow case lives.
64 AV. Additionally, when we return -1 (i.e. reached the end of directory)
67 static int fat__get_entry(struct inode *dir, loff_t *pos,
68 struct buffer_head **bh, struct msdos_dir_entry **de)
70 struct super_block *sb = dir->i_sb;
71 sector_t phys, iblock;
72 unsigned long mapped_blocks;
80 iblock = *pos >> sb->s_blocksize_bits;
81 err = fat_bmap(dir, iblock, &phys, &mapped_blocks);
83 return -1; /* beyond EOF or error */
85 fat_dir_readahead(dir, iblock, phys);
87 *bh = sb_bread(sb, phys);
89 printk(KERN_ERR "FAT: Directory bread(block %llu) failed\n",
90 (unsigned long long)phys);
92 *pos = (iblock + 1) << sb->s_blocksize_bits;
96 offset = *pos & (sb->s_blocksize - 1);
97 *pos += sizeof(struct msdos_dir_entry);
98 *de = (struct msdos_dir_entry *)((*bh)->b_data + offset);
103 static inline int fat_get_entry(struct inode *dir, loff_t *pos,
104 struct buffer_head **bh,
105 struct msdos_dir_entry **de)
107 /* Fast stuff first */
109 (*de - (struct msdos_dir_entry *)(*bh)->b_data) < MSDOS_SB(dir->i_sb)->dir_per_block - 1) {
110 *pos += sizeof(struct msdos_dir_entry);
114 return fat__get_entry(dir, pos, bh, de);
118 * Convert Unicode 16 to UTF-8, translated Unicode, or ASCII.
119 * If uni_xlate is enabled and we can't get a 1:1 conversion, use a
120 * colon as an escape character since it is normally invalid on the vfat
121 * filesystem. The following four characters are the hexadecimal digits
122 * of Unicode value. This lets us do a full dump and restore of Unicode
123 * filenames. We could get into some trouble with long Unicode names,
124 * but ignore that right now.
125 * Ahem... Stack smashing in ring 0 isn't fun. Fixed.
127 static int uni16_to_x8(unsigned char *ascii, wchar_t *uni, int uni_xlate,
128 struct nls_table *nls)
131 unsigned char *op, nc;
140 if ( (charlen = nls->uni2char(ec, op, NLS_MAX_CHARSET_SIZE)) > 0) {
143 if (uni_xlate == 1) {
145 for (k = 4; k > 0; k--) {
147 op[k] = nc > 9 ? nc + ('a' - 10)
156 /* We have some slack there, so it's OK */
167 fat_short2uni(struct nls_table *t, unsigned char *c, int clen, wchar_t *uni)
171 charlen = t->char2uni(c, clen, uni);
173 *uni = 0x003f; /* a question mark */
180 fat_short2lower_uni(struct nls_table *t, unsigned char *c, int clen, wchar_t *uni)
185 charlen = t->char2uni(c, clen, &wc);
187 *uni = 0x003f; /* a question mark */
189 } else if (charlen <= 1) {
190 unsigned char nc = t->charset2lower[*c];
195 if ( (charlen = t->char2uni(&nc, 1, uni)) < 0) {
196 *uni = 0x003f; /* a question mark */
206 fat_shortname2uni(struct nls_table *nls, unsigned char *buf, int buf_size,
207 wchar_t *uni_buf, unsigned short opt, int lower)
211 if (opt & VFAT_SFN_DISPLAY_LOWER)
212 len = fat_short2lower_uni(nls, buf, buf_size, uni_buf);
213 else if (opt & VFAT_SFN_DISPLAY_WIN95)
214 len = fat_short2uni(nls, buf, buf_size, uni_buf);
215 else if (opt & VFAT_SFN_DISPLAY_WINNT) {
217 len = fat_short2lower_uni(nls, buf, buf_size, uni_buf);
219 len = fat_short2uni(nls, buf, buf_size, uni_buf);
221 len = fat_short2uni(nls, buf, buf_size, uni_buf);
226 enum { PARSE_INVALID = 1, PARSE_NOT_LONGNAME, PARSE_EOF, };
229 * fat_parse_long - Parse extended directory entry.
231 * This function returns zero on success, negative value on error, or one of
234 * %PARSE_INVALID - Directory entry is invalid.
235 * %PARSE_NOT_LONGNAME - Directory entry does not contain longname.
236 * %PARSE_EOF - Directory has no more entries.
238 static int fat_parse_long(struct inode *dir, loff_t *pos,
239 struct buffer_head **bh, struct msdos_dir_entry **de,
240 wchar_t **unicode, unsigned char *nr_slots)
242 struct msdos_dir_slot *ds;
243 unsigned char id, slot, slots, alias_checksum;
246 *unicode = (wchar_t *)__get_free_page(GFP_KERNEL);
254 ds = (struct msdos_dir_slot *)*de;
257 return PARSE_INVALID;
259 if (slots > 20 || !slots) /* ceil(256 * 2 / 26) */
260 return PARSE_INVALID;
262 alias_checksum = ds->alias_checksum;
270 fat16_towchar(*unicode + offset, ds->name0_4, 5);
271 fat16_towchar(*unicode + offset + 5, ds->name5_10, 6);
272 fat16_towchar(*unicode + offset + 11, ds->name11_12, 2);
275 (*unicode)[offset + 13] = 0;
276 if (fat_get_entry(dir, pos, bh, de) < 0)
280 ds = (struct msdos_dir_slot *)*de;
281 if (ds->attr != ATTR_EXT)
282 return PARSE_NOT_LONGNAME;
283 if ((ds->id & ~0x40) != slot)
285 if (ds->alias_checksum != alias_checksum)
288 if ((*de)->name[0] == DELETED_FLAG)
289 return PARSE_INVALID;
290 if ((*de)->attr == ATTR_EXT)
292 if (IS_FREE((*de)->name) || ((*de)->attr & ATTR_VOLUME))
293 return PARSE_INVALID;
294 if (fat_checksum((*de)->name) != alias_checksum)
301 * Return values: negative -> error, 0 -> not found, positive -> found,
302 * value is the total amount of slots, including the shortname entry.
304 int fat_search_long(struct inode *inode, const unsigned char *name,
305 int name_len, struct fat_slot_info *sinfo)
307 struct super_block *sb = inode->i_sb;
308 struct msdos_sb_info *sbi = MSDOS_SB(sb);
309 struct buffer_head *bh = NULL;
310 struct msdos_dir_entry *de;
311 struct nls_table *nls_io = sbi->nls_io;
312 struct nls_table *nls_disk = sbi->nls_disk;
313 wchar_t bufuname[14];
314 unsigned char xlate_len, nr_slots;
315 wchar_t *unicode = NULL;
316 unsigned char work[8], bufname[260]; /* 256 + 4 */
317 int uni_xlate = sbi->options.unicode_xlate;
318 int utf8 = sbi->options.utf8;
319 int anycase = (sbi->options.name_check != 's');
320 unsigned short opt_shortname = sbi->options.shortname;
322 int chl, i, j, last_u, err;
326 if (fat_get_entry(inode, &cpos, &bh, &de) == -1)
330 if (de->name[0] == DELETED_FLAG)
332 if (de->attr != ATTR_EXT && (de->attr & ATTR_VOLUME))
334 if (de->attr != ATTR_EXT && IS_FREE(de->name))
336 if (de->attr == ATTR_EXT) {
337 int status = fat_parse_long(inode, &cpos, &bh, &de,
338 &unicode, &nr_slots);
341 else if (status == PARSE_INVALID)
343 else if (status == PARSE_NOT_LONGNAME)
345 else if (status == PARSE_EOF)
349 memcpy(work, de->name, sizeof(de->name));
350 /* see namei.c, msdos_format_name */
353 for (i = 0, j = 0, last_u = 0; i < 8;) {
355 chl = fat_shortname2uni(nls_disk, &work[i], 8 - i,
356 &bufuname[j++], opt_shortname,
357 de->lcase & CASE_LOWER_BASE);
367 fat_short2uni(nls_disk, ".", 1, &bufuname[j++]);
368 for (i = 0; i < 3;) {
369 if (!de->ext[i]) break;
370 chl = fat_shortname2uni(nls_disk, &de->ext[i], 3 - i,
371 &bufuname[j++], opt_shortname,
372 de->lcase & CASE_LOWER_EXT);
374 if (de->ext[i] != ' ')
384 bufuname[last_u] = 0x0000;
386 ?utf8_wcstombs(bufname, bufuname, sizeof(bufname))
387 :uni16_to_x8(bufname, bufuname, uni_xlate, nls_io);
388 if (xlate_len == name_len)
389 if ((!anycase && !memcmp(name, bufname, xlate_len)) ||
390 (anycase && !nls_strnicmp(nls_io, name, bufname,
396 ?utf8_wcstombs(bufname, unicode, sizeof(bufname))
397 :uni16_to_x8(bufname, unicode, uni_xlate, nls_io);
398 if (xlate_len != name_len)
400 if ((!anycase && !memcmp(name, bufname, xlate_len)) ||
401 (anycase && !nls_strnicmp(nls_io, name, bufname,
408 nr_slots++; /* include the de */
409 sinfo->slot_off = cpos - nr_slots * sizeof(*de);
410 sinfo->nr_slots = nr_slots;
413 sinfo->i_pos = fat_make_i_pos(sb, sinfo->bh, sinfo->de);
417 free_page((unsigned long)unicode);
422 EXPORT_SYMBOL_GPL(fat_search_long);
424 struct fat_ioctl_filldir_callback {
425 struct dirent __user *dirent;
428 const char *longname;
430 const char *shortname;
434 static int __fat_readdir(struct inode *inode, struct file *filp, void *dirent,
435 filldir_t filldir, int short_only, int both)
437 struct super_block *sb = inode->i_sb;
438 struct msdos_sb_info *sbi = MSDOS_SB(sb);
439 struct buffer_head *bh;
440 struct msdos_dir_entry *de;
441 struct nls_table *nls_io = sbi->nls_io;
442 struct nls_table *nls_disk = sbi->nls_disk;
443 unsigned char long_slots;
444 const char *fill_name;
446 wchar_t bufuname[14];
447 wchar_t *unicode = NULL;
448 unsigned char c, work[8], bufname[56], *ptname = bufname;
449 unsigned long lpos, dummy, *furrfu = &lpos;
450 int uni_xlate = sbi->options.unicode_xlate;
451 int isvfat = sbi->options.isvfat;
452 int utf8 = sbi->options.utf8;
453 int nocase = sbi->options.nocase;
454 unsigned short opt_shortname = sbi->options.shortname;
456 int chi, chl, i, i2, j, last, last_u, dotoffset = 0;
463 /* Fake . and .. for the root directory. */
464 if (inode->i_ino == MSDOS_ROOT_INO) {
466 if (filldir(dirent, "..", cpos+1, cpos, MSDOS_ROOT_INO, DT_DIR) < 0)
477 if (cpos & (sizeof(struct msdos_dir_entry)-1)) {
484 if (fat_get_entry(inode, &cpos, &bh, &de) == -1)
488 /* Check for long filename entry */
490 if (de->name[0] == DELETED_FLAG)
492 if (de->attr != ATTR_EXT && (de->attr & ATTR_VOLUME))
494 if (de->attr != ATTR_EXT && IS_FREE(de->name))
497 if ((de->attr & ATTR_VOLUME) || IS_FREE(de->name))
501 if (isvfat && de->attr == ATTR_EXT) {
502 int status = fat_parse_long(inode, &cpos, &bh, &de,
503 &unicode, &long_slots);
508 } else if (status == PARSE_INVALID)
510 else if (status == PARSE_NOT_LONGNAME)
512 else if (status == PARSE_EOF)
516 if (sbi->options.dotsOK) {
519 if (de->attr & ATTR_HIDDEN) {
525 memcpy(work, de->name, sizeof(de->name));
526 /* see namei.c, msdos_format_name */
529 for (i = 0, j = 0, last = 0, last_u = 0; i < 8;) {
530 if (!(c = work[i])) break;
531 chl = fat_shortname2uni(nls_disk, &work[i], 8 - i,
532 &bufuname[j++], opt_shortname,
533 de->lcase & CASE_LOWER_BASE);
535 ptname[i++] = (!nocase && c>='A' && c<='Z') ? c+32 : c;
542 for (chi = 0; chi < chl && i < 8; chi++) {
550 fat_short2uni(nls_disk, ".", 1, &bufuname[j++]);
552 for (i2 = 0; i2 < 3;) {
553 if (!(c = de->ext[i2])) break;
554 chl = fat_shortname2uni(nls_disk, &de->ext[i2], 3 - i2,
555 &bufuname[j++], opt_shortname,
556 de->lcase & CASE_LOWER_EXT);
559 ptname[i++] = (!nocase && c>='A' && c<='Z') ? c+32 : c;
566 for (chi = 0; chi < chl && i2 < 3; chi++) {
567 ptname[i++] = de->ext[i2++];
575 i = last + dotoffset;
578 lpos = cpos - (long_slots+1)*sizeof(struct msdos_dir_entry);
579 if (!memcmp(de->name, MSDOS_DOT, MSDOS_NAME))
581 else if (!memcmp(de->name, MSDOS_DOTDOT, MSDOS_NAME)) {
582 inum = parent_ino(filp->f_dentry);
584 loff_t i_pos = fat_make_i_pos(sb, bh, de);
585 struct inode *tmp = fat_iget(sb, i_pos);
590 inum = iunique(sb, MSDOS_ROOT_INO);
594 bufuname[j] = 0x0000;
595 i = utf8 ? utf8_wcstombs(bufname, bufuname, sizeof(bufname))
596 : uni16_to_x8(bufname, bufuname, uni_xlate, nls_io);
601 if (!short_only && long_slots) {
602 /* convert the unicode long name. 261 is maximum size
603 * of unicode buffer. (13 * slots + nul) */
604 void *longname = unicode + 261;
605 int buf_size = PAGE_SIZE - (261 * sizeof(unicode[0]));
607 ? utf8_wcstombs(longname, unicode, buf_size)
608 : uni16_to_x8(longname, unicode, uni_xlate, nls_io);
611 fill_name = longname;
614 /* hack for fat_ioctl_filldir() */
615 struct fat_ioctl_filldir_callback *p = dirent;
617 p->longname = longname;
618 p->long_len = long_len;
619 p->shortname = bufname;
625 if (filldir(dirent, fill_name, fill_len, *furrfu, inum,
626 (de->attr & ATTR_DIR) ? DT_DIR : DT_REG) < 0)
638 free_page((unsigned long)unicode);
644 static int fat_readdir(struct file *filp, void *dirent, filldir_t filldir)
646 struct inode *inode = filp->f_dentry->d_inode;
647 return __fat_readdir(inode, filp, dirent, filldir, 0, 0);
650 static int fat_ioctl_filldir(void *__buf, const char *name, int name_len,
651 loff_t offset, ino_t ino, unsigned int d_type)
653 struct fat_ioctl_filldir_callback *buf = __buf;
654 struct dirent __user *d1 = buf->dirent;
655 struct dirent __user *d2 = d1 + 1;
662 /* dirent has only short name */
663 if (name_len >= sizeof(d1->d_name))
664 name_len = sizeof(d1->d_name) - 1;
666 if (put_user(0, d2->d_name) ||
667 put_user(0, &d2->d_reclen) ||
668 copy_to_user(d1->d_name, name, name_len) ||
669 put_user(0, d1->d_name + name_len) ||
670 put_user(name_len, &d1->d_reclen))
673 /* dirent has short and long name */
674 const char *longname = buf->longname;
675 int long_len = buf->long_len;
676 const char *shortname = buf->shortname;
677 int short_len = buf->short_len;
679 if (long_len >= sizeof(d1->d_name))
680 long_len = sizeof(d1->d_name) - 1;
681 if (short_len >= sizeof(d1->d_name))
682 short_len = sizeof(d1->d_name) - 1;
684 if (copy_to_user(d2->d_name, longname, long_len) ||
685 put_user(0, d2->d_name + long_len) ||
686 put_user(long_len, &d2->d_reclen) ||
687 put_user(ino, &d2->d_ino) ||
688 put_user(offset, &d2->d_off) ||
689 copy_to_user(d1->d_name, shortname, short_len) ||
690 put_user(0, d1->d_name + short_len) ||
691 put_user(short_len, &d1->d_reclen))
696 buf->result = -EFAULT;
700 static int fat_dir_ioctl(struct inode * inode, struct file * filp,
701 unsigned int cmd, unsigned long arg)
703 struct fat_ioctl_filldir_callback buf;
704 struct dirent __user *d1;
705 int ret, short_only, both;
708 case VFAT_IOCTL_READDIR_SHORT:
712 case VFAT_IOCTL_READDIR_BOTH:
717 return fat_generic_ioctl(inode, filp, cmd, arg);
720 d1 = (struct dirent __user *)arg;
721 if (!access_ok(VERIFY_WRITE, d1, sizeof(struct dirent[2])))
724 * Yes, we don't need this put_user() absolutely. However old
725 * code didn't return the right value. So, app use this value,
726 * in order to check whether it is EOF.
728 if (put_user(0, &d1->d_reclen))
733 mutex_lock(&inode->i_mutex);
735 if (!IS_DEADDIR(inode)) {
736 ret = __fat_readdir(inode, filp, &buf, fat_ioctl_filldir,
739 mutex_unlock(&inode->i_mutex);
746 #define VFAT_IOCTL_READDIR_BOTH32 _IOR('r', 1, struct compat_dirent[2])
747 #define VFAT_IOCTL_READDIR_SHORT32 _IOR('r', 2, struct compat_dirent[2])
749 static long fat_compat_put_dirent32(struct dirent *d,
750 struct compat_dirent __user *d32)
752 if (!access_ok(VERIFY_WRITE, d32, sizeof(struct compat_dirent)))
755 __put_user(d->d_ino, &d32->d_ino);
756 __put_user(d->d_off, &d32->d_off);
757 __put_user(d->d_reclen, &d32->d_reclen);
758 if (__copy_to_user(d32->d_name, d->d_name, d->d_reclen))
764 static long fat_compat_dir_ioctl(struct file *file, unsigned cmd,
767 struct compat_dirent __user *p = compat_ptr(arg);
769 mm_segment_t oldfs = get_fs();
773 case VFAT_IOCTL_READDIR_BOTH32:
774 cmd = VFAT_IOCTL_READDIR_BOTH;
776 case VFAT_IOCTL_READDIR_SHORT32:
777 cmd = VFAT_IOCTL_READDIR_SHORT;
785 ret = fat_dir_ioctl(file->f_dentry->d_inode, file,
786 cmd, (unsigned long) &d);
790 ret |= fat_compat_put_dirent32(&d[0], p);
791 ret |= fat_compat_put_dirent32(&d[1], p + 1);
795 #endif /* CONFIG_COMPAT */
797 const struct file_operations fat_dir_operations = {
798 .read = generic_read_dir,
799 .readdir = fat_readdir,
800 .ioctl = fat_dir_ioctl,
802 .compat_ioctl = fat_compat_dir_ioctl,
807 static int fat_get_short_entry(struct inode *dir, loff_t *pos,
808 struct buffer_head **bh,
809 struct msdos_dir_entry **de)
811 while (fat_get_entry(dir, pos, bh, de) >= 0) {
812 /* free entry or long name entry or volume label */
813 if (!IS_FREE((*de)->name) && !((*de)->attr & ATTR_VOLUME))
820 * The ".." entry can not provide the "struct fat_slot_info" informations
821 * for inode. So, this function provide the some informations only.
823 int fat_get_dotdot_entry(struct inode *dir, struct buffer_head **bh,
824 struct msdos_dir_entry **de, loff_t *i_pos)
830 while (fat_get_short_entry(dir, &offset, bh, de) >= 0) {
831 if (!strncmp((*de)->name, MSDOS_DOTDOT, MSDOS_NAME)) {
832 *i_pos = fat_make_i_pos(dir->i_sb, *bh, *de);
839 EXPORT_SYMBOL_GPL(fat_get_dotdot_entry);
841 /* See if directory is empty */
842 int fat_dir_empty(struct inode *dir)
844 struct buffer_head *bh;
845 struct msdos_dir_entry *de;
851 while (fat_get_short_entry(dir, &cpos, &bh, &de) >= 0) {
852 if (strncmp(de->name, MSDOS_DOT , MSDOS_NAME) &&
853 strncmp(de->name, MSDOS_DOTDOT, MSDOS_NAME)) {
862 EXPORT_SYMBOL_GPL(fat_dir_empty);
865 * fat_subdirs counts the number of sub-directories of dir. It can be run
866 * on directories being created.
868 int fat_subdirs(struct inode *dir)
870 struct buffer_head *bh;
871 struct msdos_dir_entry *de;
877 while (fat_get_short_entry(dir, &cpos, &bh, &de) >= 0) {
878 if (de->attr & ATTR_DIR)
886 * Scans a directory for a given file (name points to its formatted name).
887 * Returns an error code or zero.
889 int fat_scan(struct inode *dir, const unsigned char *name,
890 struct fat_slot_info *sinfo)
892 struct super_block *sb = dir->i_sb;
896 while (fat_get_short_entry(dir, &sinfo->slot_off, &sinfo->bh,
898 if (!strncmp(sinfo->de->name, name, MSDOS_NAME)) {
899 sinfo->slot_off -= sizeof(*sinfo->de);
901 sinfo->i_pos = fat_make_i_pos(sb, sinfo->bh, sinfo->de);
908 EXPORT_SYMBOL_GPL(fat_scan);
910 static int __fat_remove_entries(struct inode *dir, loff_t pos, int nr_slots)
912 struct super_block *sb = dir->i_sb;
913 struct buffer_head *bh;
914 struct msdos_dir_entry *de, *endp;
915 int err = 0, orig_slots;
919 if (fat_get_entry(dir, &pos, &bh, &de) < 0) {
924 orig_slots = nr_slots;
925 endp = (struct msdos_dir_entry *)(bh->b_data + sb->s_blocksize);
926 while (nr_slots && de < endp) {
927 de->name[0] = DELETED_FLAG;
931 mark_buffer_dirty(bh);
933 err = sync_dirty_buffer(bh);
938 /* pos is *next* de's position, so this does `- sizeof(de)' */
939 pos += ((orig_slots - nr_slots) * sizeof(*de)) - sizeof(*de);
945 int fat_remove_entries(struct inode *dir, struct fat_slot_info *sinfo)
947 struct msdos_dir_entry *de;
948 struct buffer_head *bh;
949 int err = 0, nr_slots;
952 * First stage: Remove the shortname. By this, the directory
955 nr_slots = sinfo->nr_slots;
960 while (nr_slots && de >= (struct msdos_dir_entry *)bh->b_data) {
961 de->name[0] = DELETED_FLAG;
965 mark_buffer_dirty(bh);
967 err = sync_dirty_buffer(bh);
975 * Second stage: remove the remaining longname slots.
976 * (This directory entry is already removed, and so return
979 err = __fat_remove_entries(dir, sinfo->slot_off, nr_slots);
982 "FAT: Couldn't remove the long name slots\n");
986 dir->i_mtime = dir->i_atime = CURRENT_TIME_SEC;
988 (void)fat_sync_inode(dir);
990 mark_inode_dirty(dir);
995 EXPORT_SYMBOL_GPL(fat_remove_entries);
997 static int fat_zeroed_cluster(struct inode *dir, sector_t blknr, int nr_used,
998 struct buffer_head **bhs, int nr_bhs)
1000 struct super_block *sb = dir->i_sb;
1001 sector_t last_blknr = blknr + MSDOS_SB(sb)->sec_per_clus;
1004 /* Zeroing the unused blocks on this cluster */
1007 while (blknr < last_blknr) {
1008 bhs[n] = sb_getblk(sb, blknr);
1013 memset(bhs[n]->b_data, 0, sb->s_blocksize);
1014 set_buffer_uptodate(bhs[n]);
1015 mark_buffer_dirty(bhs[n]);
1020 if (IS_DIRSYNC(dir)) {
1021 err = fat_sync_bhs(bhs, n);
1025 for (i = 0; i < n; i++)
1030 if (IS_DIRSYNC(dir)) {
1031 err = fat_sync_bhs(bhs, n);
1035 for (i = 0; i < n; i++)
1041 for (i = 0; i < n; i++)
1046 int fat_alloc_new_dir(struct inode *dir, struct timespec *ts)
1048 struct super_block *sb = dir->i_sb;
1049 struct msdos_sb_info *sbi = MSDOS_SB(sb);
1050 struct buffer_head *bhs[MAX_BUF_PER_PAGE];
1051 struct msdos_dir_entry *de;
1056 err = fat_alloc_clusters(dir, &cluster, 1);
1060 blknr = fat_clus_to_blknr(sbi, cluster);
1061 bhs[0] = sb_getblk(sb, blknr);
1067 fat_date_unix2dos(ts->tv_sec, &time, &date);
1069 de = (struct msdos_dir_entry *)bhs[0]->b_data;
1070 /* filling the new directory slots ("." and ".." entries) */
1071 memcpy(de[0].name, MSDOS_DOT, MSDOS_NAME);
1072 memcpy(de[1].name, MSDOS_DOTDOT, MSDOS_NAME);
1073 de->attr = de[1].attr = ATTR_DIR;
1074 de[0].lcase = de[1].lcase = 0;
1075 de[0].time = de[1].time = time;
1076 de[0].date = de[1].date = date;
1077 de[0].ctime_cs = de[1].ctime_cs = 0;
1078 if (sbi->options.isvfat) {
1079 /* extra timestamps */
1080 de[0].ctime = de[1].ctime = time;
1081 de[0].adate = de[0].cdate = de[1].adate = de[1].cdate = date;
1083 de[0].ctime = de[1].ctime = 0;
1084 de[0].adate = de[0].cdate = de[1].adate = de[1].cdate = 0;
1086 de[0].start = cpu_to_le16(cluster);
1087 de[0].starthi = cpu_to_le16(cluster >> 16);
1088 de[1].start = cpu_to_le16(MSDOS_I(dir)->i_logstart);
1089 de[1].starthi = cpu_to_le16(MSDOS_I(dir)->i_logstart >> 16);
1090 de[0].size = de[1].size = 0;
1091 memset(de + 2, 0, sb->s_blocksize - 2 * sizeof(*de));
1092 set_buffer_uptodate(bhs[0]);
1093 mark_buffer_dirty(bhs[0]);
1095 err = fat_zeroed_cluster(dir, blknr, 1, bhs, MAX_BUF_PER_PAGE);
1102 fat_free_clusters(dir, cluster);
1107 EXPORT_SYMBOL_GPL(fat_alloc_new_dir);
1109 static int fat_add_new_entries(struct inode *dir, void *slots, int nr_slots,
1110 int *nr_cluster, struct msdos_dir_entry **de,
1111 struct buffer_head **bh, loff_t *i_pos)
1113 struct super_block *sb = dir->i_sb;
1114 struct msdos_sb_info *sbi = MSDOS_SB(sb);
1115 struct buffer_head *bhs[MAX_BUF_PER_PAGE];
1116 sector_t blknr, start_blknr, last_blknr;
1117 unsigned long size, copy;
1118 int err, i, n, offset, cluster[2];
1121 * The minimum cluster size is 512bytes, and maximum entry
1122 * size is 32*slots (672bytes). So, iff the cluster size is
1123 * 512bytes, we may need two clusters.
1125 size = nr_slots * sizeof(struct msdos_dir_entry);
1126 *nr_cluster = (size + (sbi->cluster_size - 1)) >> sbi->cluster_bits;
1127 BUG_ON(*nr_cluster > 2);
1129 err = fat_alloc_clusters(dir, cluster, *nr_cluster);
1134 * First stage: Fill the directory entry. NOTE: This cluster
1135 * is not referenced from any inode yet, so updates order is
1140 start_blknr = blknr = fat_clus_to_blknr(sbi, cluster[i]);
1141 last_blknr = start_blknr + sbi->sec_per_clus;
1142 while (blknr < last_blknr) {
1143 bhs[n] = sb_getblk(sb, blknr);
1149 /* fill the directory entry */
1150 copy = min(size, sb->s_blocksize);
1151 memcpy(bhs[n]->b_data, slots, copy);
1154 set_buffer_uptodate(bhs[n]);
1155 mark_buffer_dirty(bhs[n]);
1161 } while (++i < *nr_cluster);
1163 memset(bhs[n]->b_data + copy, 0, sb->s_blocksize - copy);
1164 offset = copy - sizeof(struct msdos_dir_entry);
1167 *de = (struct msdos_dir_entry *)((*bh)->b_data + offset);
1168 *i_pos = fat_make_i_pos(sb, *bh, *de);
1170 /* Second stage: clear the rest of cluster, and write outs */
1171 err = fat_zeroed_cluster(dir, start_blknr, ++n, bhs, MAX_BUF_PER_PAGE);
1182 for (i = 0; i < n; i++)
1184 fat_free_clusters(dir, cluster[0]);
1189 int fat_add_entries(struct inode *dir, void *slots, int nr_slots,
1190 struct fat_slot_info *sinfo)
1192 struct super_block *sb = dir->i_sb;
1193 struct msdos_sb_info *sbi = MSDOS_SB(sb);
1194 struct buffer_head *bh, *prev, *bhs[3]; /* 32*slots (672bytes) */
1195 struct msdos_dir_entry *de;
1196 int err, free_slots, i, nr_bhs;
1199 sinfo->nr_slots = nr_slots;
1201 /* First stage: search free direcotry entries */
1202 free_slots = nr_bhs = 0;
1206 while (fat_get_entry(dir, &pos, &bh, &de) > -1) {
1207 /* check the maximum size of directory */
1208 if (pos >= FAT_MAX_DIR_SIZE)
1211 if (IS_FREE(de->name)) {
1214 bhs[nr_bhs] = prev = bh;
1218 if (free_slots == nr_slots)
1221 for (i = 0; i < nr_bhs; i++)
1224 free_slots = nr_bhs = 0;
1227 if (dir->i_ino == MSDOS_ROOT_INO) {
1228 if (sbi->fat_bits != 32)
1230 } else if (MSDOS_I(dir)->i_start == 0) {
1231 printk(KERN_ERR "FAT: Corrupted directory (i_pos %lld)\n",
1232 MSDOS_I(dir)->i_pos);
1239 pos -= free_slots * sizeof(*de);
1240 nr_slots -= free_slots;
1243 * Second stage: filling the free entries with new entries.
1244 * NOTE: If this slots has shortname, first, we write
1245 * the long name slots, then write the short name.
1247 int size = free_slots * sizeof(*de);
1248 int offset = pos & (sb->s_blocksize - 1);
1249 int long_bhs = nr_bhs - (nr_slots == 0);
1251 /* Fill the long name slots. */
1252 for (i = 0; i < long_bhs; i++) {
1253 int copy = min_t(int, sb->s_blocksize - offset, size);
1254 memcpy(bhs[i]->b_data + offset, slots, copy);
1255 mark_buffer_dirty(bhs[i]);
1260 if (long_bhs && IS_DIRSYNC(dir))
1261 err = fat_sync_bhs(bhs, long_bhs);
1262 if (!err && i < nr_bhs) {
1263 /* Fill the short name slot. */
1264 int copy = min_t(int, sb->s_blocksize - offset, size);
1265 memcpy(bhs[i]->b_data + offset, slots, copy);
1266 mark_buffer_dirty(bhs[i]);
1267 if (IS_DIRSYNC(dir))
1268 err = sync_dirty_buffer(bhs[i]);
1270 for (i = 0; i < nr_bhs; i++)
1277 int cluster, nr_cluster;
1280 * Third stage: allocate the cluster for new entries.
1281 * And initialize the cluster with new entries, then
1282 * add the cluster to dir.
1284 cluster = fat_add_new_entries(dir, slots, nr_slots, &nr_cluster,
1290 err = fat_chain_add(dir, cluster, nr_cluster);
1292 fat_free_clusters(dir, cluster);
1295 if (dir->i_size & (sbi->cluster_size - 1)) {
1296 fat_fs_panic(sb, "Odd directory size");
1297 dir->i_size = (dir->i_size + sbi->cluster_size - 1)
1298 & ~((loff_t)sbi->cluster_size - 1);
1300 dir->i_size += nr_cluster << sbi->cluster_bits;
1301 MSDOS_I(dir)->mmu_private += nr_cluster << sbi->cluster_bits;
1303 sinfo->slot_off = pos;
1306 sinfo->i_pos = fat_make_i_pos(sb, sinfo->bh, sinfo->de);
1312 for (i = 0; i < nr_bhs; i++)
1319 __fat_remove_entries(dir, pos, free_slots);
1323 EXPORT_SYMBOL_GPL(fat_add_entries);