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))
732 mutex_lock(&inode->i_mutex);
734 if (!IS_DEADDIR(inode)) {
735 ret = __fat_readdir(inode, filp, &buf, fat_ioctl_filldir,
738 mutex_unlock(&inode->i_mutex);
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);