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mm: fix exec activate_mm vs TLB shootdown and lazy tlb switching race
[linux/fpc-iii.git] / fs / fat / dir.c
blob971e369517a734a45578213ba37a114c4eb1a6c9
1 /*
2 * linux/fs/fat/dir.c
3 *
4 * directory handling functions for fat-based filesystems
5 *
6 * Written 1992,1993 by Werner Almesberger
7 *
8 * Hidden files 1995 by Albert Cahalan <albert@ccs.neu.edu> <adc@coe.neu.edu>
9 *
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>
14 */
15
16 #include <linux/slab.h>
17 #include <linux/compat.h>
18 #include <linux/uaccess.h>
19 #include "fat.h"
20
21 /*
22 * Maximum buffer size of short name.
23 * [(MSDOS_NAME + '.') * max one char + nul]
24 * For msdos style, ['.' (hidden) + MSDOS_NAME + '.' + nul]
25 */
26 #define FAT_MAX_SHORT_SIZE ((MSDOS_NAME + 1) * NLS_MAX_CHARSET_SIZE + 1)
27 /*
28 * Maximum buffer size of unicode chars from slots.
29 * [(max longname slots * 13 (size in a slot) + nul) * sizeof(wchar_t)]
30 */
31 #define FAT_MAX_UNI_CHARS ((MSDOS_SLOTS - 1) * 13 + 1)
32 #define FAT_MAX_UNI_SIZE (FAT_MAX_UNI_CHARS * sizeof(wchar_t))
33
34 static inline unsigned char fat_tolower(unsigned char c)
35 {
36 return ((c >= 'A') && (c <= 'Z')) ? c+32 : c;
37 }
38
39 static inline loff_t fat_make_i_pos(struct super_block *sb,
40 struct buffer_head *bh,
41 struct msdos_dir_entry *de)
42 {
43 return ((loff_t)bh->b_blocknr << MSDOS_SB(sb)->dir_per_block_bits)
44 | (de - (struct msdos_dir_entry *)bh->b_data);
45 }
46
47 static inline void fat_dir_readahead(struct inode *dir, sector_t iblock,
48 sector_t phys)
49 {
50 struct super_block *sb = dir->i_sb;
51 struct msdos_sb_info *sbi = MSDOS_SB(sb);
52 struct buffer_head *bh;
53 int sec;
54
55 /* This is not a first sector of cluster, or sec_per_clus == 1 */
56 if ((iblock & (sbi->sec_per_clus - 1)) || sbi->sec_per_clus == 1)
57 return;
58 /* root dir of FAT12/FAT16 */
59 if ((sbi->fat_bits != 32) && (dir->i_ino == MSDOS_ROOT_INO))
60 return;
61
62 bh = sb_find_get_block(sb, phys);
63 if (bh == NULL || !buffer_uptodate(bh)) {
64 for (sec = 0; sec < sbi->sec_per_clus; sec++)
65 sb_breadahead(sb, phys + sec);
66 }
67 brelse(bh);
68 }
69
70 /* Returns the inode number of the directory entry at offset pos. If bh is
71 non-NULL, it is brelse'd before. Pos is incremented. The buffer header is
72 returned in bh.
73 AV. Most often we do it item-by-item. Makes sense to optimize.
74 AV. OK, there we go: if both bh and de are non-NULL we assume that we just
75 AV. want the next entry (took one explicit de=NULL in vfat/namei.c).
76 AV. It's done in fat_get_entry() (inlined), here the slow case lives.
77 AV. Additionally, when we return -1 (i.e. reached the end of directory)
78 AV. we make bh NULL.
79 */
80 static int fat__get_entry(struct inode *dir, loff_t *pos,
81 struct buffer_head **bh, struct msdos_dir_entry **de)
82 {
83 struct super_block *sb = dir->i_sb;
84 sector_t phys, iblock;
85 unsigned long mapped_blocks;
86 int err, offset;
87
88 next:
89 if (*bh)
90 brelse(*bh);
91
92 *bh = NULL;
93 iblock = *pos >> sb->s_blocksize_bits;
94 err = fat_bmap(dir, iblock, &phys, &mapped_blocks, 0, false);
95 if (err || !phys)
96 return -1; /* beyond EOF or error */
97
98 fat_dir_readahead(dir, iblock, phys);
99
100 *bh = sb_bread(sb, phys);
101 if (*bh == NULL) {
102 fat_msg_ratelimit(sb, KERN_ERR,
103 "Directory bread(block %llu) failed", (llu)phys);
104 /* skip this block */
105 *pos = (iblock + 1) << sb->s_blocksize_bits;
106 goto next;
107 }
108
109 offset = *pos & (sb->s_blocksize - 1);
110 *pos += sizeof(struct msdos_dir_entry);
111 *de = (struct msdos_dir_entry *)((*bh)->b_data + offset);
112
113 return 0;
114 }
115
116 static inline int fat_get_entry(struct inode *dir, loff_t *pos,
117 struct buffer_head **bh,
118 struct msdos_dir_entry **de)
119 {
120 /* Fast stuff first */
121 if (*bh && *de &&
122 (*de - (struct msdos_dir_entry *)(*bh)->b_data) <
123 MSDOS_SB(dir->i_sb)->dir_per_block - 1) {
124 *pos += sizeof(struct msdos_dir_entry);
125 (*de)++;
126 return 0;
127 }
128 return fat__get_entry(dir, pos, bh, de);
129 }
130
131 /*
132 * Convert Unicode 16 to UTF-8, translated Unicode, or ASCII.
133 * If uni_xlate is enabled and we can't get a 1:1 conversion, use a
134 * colon as an escape character since it is normally invalid on the vfat
135 * filesystem. The following four characters are the hexadecimal digits
136 * of Unicode value. This lets us do a full dump and restore of Unicode
137 * filenames. We could get into some trouble with long Unicode names,
138 * but ignore that right now.
139 * Ahem... Stack smashing in ring 0 isn't fun. Fixed.
140 */
141 static int uni16_to_x8(struct super_block *sb, unsigned char *ascii,
142 const wchar_t *uni, int len, struct nls_table *nls)
143 {
144 int uni_xlate = MSDOS_SB(sb)->options.unicode_xlate;
145 const wchar_t *ip;
146 wchar_t ec;
147 unsigned char *op;
148 int charlen;
149
150 ip = uni;
151 op = ascii;
152
153 while (*ip && ((len - NLS_MAX_CHARSET_SIZE) > 0)) {
154 ec = *ip++;
155 charlen = nls->uni2char(ec, op, NLS_MAX_CHARSET_SIZE);
156 if (charlen > 0) {
157 op += charlen;
158 len -= charlen;
159 } else {
160 if (uni_xlate == 1) {
161 *op++ = ':';
162 op = hex_byte_pack(op, ec >> 8);
163 op = hex_byte_pack(op, ec);
164 len -= 5;
165 } else {
166 *op++ = '?';
167 len--;
168 }
169 }
170 }
171
172 if (unlikely(*ip)) {
173 fat_msg(sb, KERN_WARNING,
174 "filename was truncated while converting.");
175 }
176
177 *op = 0;
178 return op - ascii;
179 }
180
181 static inline int fat_uni_to_x8(struct super_block *sb, const wchar_t *uni,
182 unsigned char *buf, int size)
183 {
184 struct msdos_sb_info *sbi = MSDOS_SB(sb);
185 if (sbi->options.utf8)
186 return utf16s_to_utf8s(uni, FAT_MAX_UNI_CHARS,
187 UTF16_HOST_ENDIAN, buf, size);
188 else
189 return uni16_to_x8(sb, buf, uni, size, sbi->nls_io);
190 }
191
192 static inline int
193 fat_short2uni(struct nls_table *t, unsigned char *c, int clen, wchar_t *uni)
194 {
195 int charlen;
196
197 charlen = t->char2uni(c, clen, uni);
198 if (charlen < 0) {
199 *uni = 0x003f; /* a question mark */
200 charlen = 1;
201 }
202 return charlen;
203 }
204
205 static inline int
206 fat_short2lower_uni(struct nls_table *t, unsigned char *c,
207 int clen, wchar_t *uni)
208 {
209 int charlen;
210 wchar_t wc;
211
212 charlen = t->char2uni(c, clen, &wc);
213 if (charlen < 0) {
214 *uni = 0x003f; /* a question mark */
215 charlen = 1;
216 } else if (charlen <= 1) {
217 unsigned char nc = t->charset2lower[*c];
218
219 if (!nc)
220 nc = *c;
221
222 charlen = t->char2uni(&nc, 1, uni);
223 if (charlen < 0) {
224 *uni = 0x003f; /* a question mark */
225 charlen = 1;
226 }
227 } else
228 *uni = wc;
229
230 return charlen;
231 }
232
233 static inline int
234 fat_shortname2uni(struct nls_table *nls, unsigned char *buf, int buf_size,
235 wchar_t *uni_buf, unsigned short opt, int lower)
236 {
237 int len = 0;
238
239 if (opt & VFAT_SFN_DISPLAY_LOWER)
240 len = fat_short2lower_uni(nls, buf, buf_size, uni_buf);
241 else if (opt & VFAT_SFN_DISPLAY_WIN95)
242 len = fat_short2uni(nls, buf, buf_size, uni_buf);
243 else if (opt & VFAT_SFN_DISPLAY_WINNT) {
244 if (lower)
245 len = fat_short2lower_uni(nls, buf, buf_size, uni_buf);
246 else
247 len = fat_short2uni(nls, buf, buf_size, uni_buf);
248 } else
249 len = fat_short2uni(nls, buf, buf_size, uni_buf);
250
251 return len;
252 }
253
254 static inline int fat_name_match(struct msdos_sb_info *sbi,
255 const unsigned char *a, int a_len,
256 const unsigned char *b, int b_len)
257 {
258 if (a_len != b_len)
259 return 0;
260
261 if (sbi->options.name_check != 's')
262 return !nls_strnicmp(sbi->nls_io, a, b, a_len);
263 else
264 return !memcmp(a, b, a_len);
265 }
266
267 enum { PARSE_INVALID = 1, PARSE_NOT_LONGNAME, PARSE_EOF, };
268
269 /**
270 * fat_parse_long - Parse extended directory entry.
271 *
272 * This function returns zero on success, negative value on error, or one of
273 * the following:
274 *
275 * %PARSE_INVALID - Directory entry is invalid.
276 * %PARSE_NOT_LONGNAME - Directory entry does not contain longname.
277 * %PARSE_EOF - Directory has no more entries.
278 */
279 static int fat_parse_long(struct inode *dir, loff_t *pos,
280 struct buffer_head **bh, struct msdos_dir_entry **de,
281 wchar_t **unicode, unsigned char *nr_slots)
282 {
283 struct msdos_dir_slot *ds;
284 unsigned char id, slot, slots, alias_checksum;
285
286 if (!*unicode) {
287 *unicode = __getname();
288 if (!*unicode) {
289 brelse(*bh);
290 return -ENOMEM;
291 }
292 }
293 parse_long:
294 slots = 0;
295 ds = (struct msdos_dir_slot *)*de;
296 id = ds->id;
297 if (!(id & 0x40))
298 return PARSE_INVALID;
299 slots = id & ~0x40;
300 if (slots > 20 || !slots) /* ceil(256 * 2 / 26) */
301 return PARSE_INVALID;
302 *nr_slots = slots;
303 alias_checksum = ds->alias_checksum;
304
305 slot = slots;
306 while (1) {
307 int offset;
308
309 slot--;
310 offset = slot * 13;
311 fat16_towchar(*unicode + offset, ds->name0_4, 5);
312 fat16_towchar(*unicode + offset + 5, ds->name5_10, 6);
313 fat16_towchar(*unicode + offset + 11, ds->name11_12, 2);
314
315 if (ds->id & 0x40)
316 (*unicode)[offset + 13] = 0;
317 if (fat_get_entry(dir, pos, bh, de) < 0)
318 return PARSE_EOF;
319 if (slot == 0)
320 break;
321 ds = (struct msdos_dir_slot *)*de;
322 if (ds->attr != ATTR_EXT)
323 return PARSE_NOT_LONGNAME;
324 if ((ds->id & ~0x40) != slot)
325 goto parse_long;
326 if (ds->alias_checksum != alias_checksum)
327 goto parse_long;
328 }
329 if ((*de)->name[0] == DELETED_FLAG)
330 return PARSE_INVALID;
331 if ((*de)->attr == ATTR_EXT)
332 goto parse_long;
333 if (IS_FREE((*de)->name) || ((*de)->attr & ATTR_VOLUME))
334 return PARSE_INVALID;
335 if (fat_checksum((*de)->name) != alias_checksum)
336 *nr_slots = 0;
337
338 return 0;
339 }
340
341 /**
342 * fat_parse_short - Parse MS-DOS (short) directory entry.
343 * @sb: superblock
344 * @de: directory entry to parse
345 * @name: FAT_MAX_SHORT_SIZE array in which to place extracted name
346 * @dot_hidden: Nonzero == prepend '.' to names with ATTR_HIDDEN
347 *
348 * Returns the number of characters extracted into 'name'.
349 */
350 static int fat_parse_short(struct super_block *sb,
351 const struct msdos_dir_entry *de,
352 unsigned char *name, int dot_hidden)
353 {
354 const struct msdos_sb_info *sbi = MSDOS_SB(sb);
355 int isvfat = sbi->options.isvfat;
356 int nocase = sbi->options.nocase;
357 unsigned short opt_shortname = sbi->options.shortname;
358 struct nls_table *nls_disk = sbi->nls_disk;
359 wchar_t uni_name[14];
360 unsigned char c, work[MSDOS_NAME];
361 unsigned char *ptname = name;
362 int chi, chl, i, j, k;
363 int dotoffset = 0;
364 int name_len = 0, uni_len = 0;
365
366 if (!isvfat && dot_hidden && (de->attr & ATTR_HIDDEN)) {
367 *ptname++ = '.';
368 dotoffset = 1;
369 }
370
371 memcpy(work, de->name, sizeof(work));
372 /* see namei.c, msdos_format_name */
373 if (work[0] == 0x05)
374 work[0] = 0xE5;
375
376 /* Filename */
377 for (i = 0, j = 0; i < 8;) {
378 c = work[i];
379 if (!c)
380 break;
381 chl = fat_shortname2uni(nls_disk, &work[i], 8 - i,
382 &uni_name[j++], opt_shortname,
383 de->lcase & CASE_LOWER_BASE);
384 if (chl <= 1) {
385 if (!isvfat)
386 ptname[i] = nocase ? c : fat_tolower(c);
387 i++;
388 if (c != ' ') {
389 name_len = i;
390 uni_len = j;
391 }
392 } else {
393 uni_len = j;
394 if (isvfat)
395 i += min(chl, 8-i);
396 else {
397 for (chi = 0; chi < chl && i < 8; chi++, i++)
398 ptname[i] = work[i];
399 }
400 if (chl)
401 name_len = i;
402 }
403 }
404
405 i = name_len;
406 j = uni_len;
407 fat_short2uni(nls_disk, ".", 1, &uni_name[j++]);
408 if (!isvfat)
409 ptname[i] = '.';
410 i++;
411
412 /* Extension */
413 for (k = 8; k < MSDOS_NAME;) {
414 c = work[k];
415 if (!c)
416 break;
417 chl = fat_shortname2uni(nls_disk, &work[k], MSDOS_NAME - k,
418 &uni_name[j++], opt_shortname,
419 de->lcase & CASE_LOWER_EXT);
420 if (chl <= 1) {
421 k++;
422 if (!isvfat)
423 ptname[i] = nocase ? c : fat_tolower(c);
424 i++;
425 if (c != ' ') {
426 name_len = i;
427 uni_len = j;
428 }
429 } else {
430 uni_len = j;
431 if (isvfat) {
432 int offset = min(chl, MSDOS_NAME-k);
433 k += offset;
434 i += offset;
435 } else {
436 for (chi = 0; chi < chl && k < MSDOS_NAME;
437 chi++, i++, k++) {
438 ptname[i] = work[k];
439 }
440 }
441 if (chl)
442 name_len = i;
443 }
444 }
445
446 if (name_len > 0) {
447 name_len += dotoffset;
448
449 if (sbi->options.isvfat) {
450 uni_name[uni_len] = 0x0000;
451 name_len = fat_uni_to_x8(sb, uni_name, name,
452 FAT_MAX_SHORT_SIZE);
453 }
454 }
455
456 return name_len;
457 }
458
459 /*
460 * Return values: negative -> error/not found, 0 -> found.
461 */
462 int fat_search_long(struct inode *inode, const unsigned char *name,
463 int name_len, struct fat_slot_info *sinfo)
464 {
465 struct super_block *sb = inode->i_sb;
466 struct msdos_sb_info *sbi = MSDOS_SB(sb);
467 struct buffer_head *bh = NULL;
468 struct msdos_dir_entry *de;
469 unsigned char nr_slots;
470 wchar_t *unicode = NULL;
471 unsigned char bufname[FAT_MAX_SHORT_SIZE];
472 loff_t cpos = 0;
473 int err, len;
474
475 err = -ENOENT;
476 while (1) {
477 if (fat_get_entry(inode, &cpos, &bh, &de) == -1)
478 goto end_of_dir;
479 parse_record:
480 nr_slots = 0;
481 if (de->name[0] == DELETED_FLAG)
482 continue;
483 if (de->attr != ATTR_EXT && (de->attr & ATTR_VOLUME))
484 continue;
485 if (de->attr != ATTR_EXT && IS_FREE(de->name))
486 continue;
487 if (de->attr == ATTR_EXT) {
488 int status = fat_parse_long(inode, &cpos, &bh, &de,
489 &unicode, &nr_slots);
490 if (status < 0) {
491 err = status;
492 goto end_of_dir;
493 } else if (status == PARSE_INVALID)
494 continue;
495 else if (status == PARSE_NOT_LONGNAME)
496 goto parse_record;
497 else if (status == PARSE_EOF)
498 goto end_of_dir;
499 }
500
501 /* Never prepend '.' to hidden files here.
502 * That is done only for msdos mounts (and only when
503 * 'dotsOK=yes'); if we are executing here, it is in the
504 * context of a vfat mount.
505 */
506 len = fat_parse_short(sb, de, bufname, 0);
507 if (len == 0)
508 continue;
509
510 /* Compare shortname */
511 if (fat_name_match(sbi, name, name_len, bufname, len))
512 goto found;
513
514 if (nr_slots) {
515 void *longname = unicode + FAT_MAX_UNI_CHARS;
516 int size = PATH_MAX - FAT_MAX_UNI_SIZE;
517
518 /* Compare longname */
519 len = fat_uni_to_x8(sb, unicode, longname, size);
520 if (fat_name_match(sbi, name, name_len, longname, len))
521 goto found;
522 }
523 }
524
525 found:
526 nr_slots++; /* include the de */
527 sinfo->slot_off = cpos - nr_slots * sizeof(*de);
528 sinfo->nr_slots = nr_slots;
529 sinfo->de = de;
530 sinfo->bh = bh;
531 sinfo->i_pos = fat_make_i_pos(sb, sinfo->bh, sinfo->de);
532 err = 0;
533 end_of_dir:
534 if (unicode)
535 __putname(unicode);
536
537 return err;
538 }
539 EXPORT_SYMBOL_GPL(fat_search_long);
540
541 struct fat_ioctl_filldir_callback {
542 struct dir_context ctx;
543 void __user *dirent;
544 int result;
545 /* for dir ioctl */
546 const char *longname;
547 int long_len;
548 const char *shortname;
549 int short_len;
550 };
551
552 static int __fat_readdir(struct inode *inode, struct file *file,
553 struct dir_context *ctx, int short_only,
554 struct fat_ioctl_filldir_callback *both)
555 {
556 struct super_block *sb = inode->i_sb;
557 struct msdos_sb_info *sbi = MSDOS_SB(sb);
558 struct buffer_head *bh;
559 struct msdos_dir_entry *de;
560 unsigned char nr_slots;
561 wchar_t *unicode = NULL;
562 unsigned char bufname[FAT_MAX_SHORT_SIZE];
563 int isvfat = sbi->options.isvfat;
564 const char *fill_name = NULL;
565 int fake_offset = 0;
566 loff_t cpos;
567 int short_len = 0, fill_len = 0;
568 int ret = 0;
569
570 mutex_lock(&sbi->s_lock);
571
572 cpos = ctx->pos;
573 /* Fake . and .. for the root directory. */
574 if (inode->i_ino == MSDOS_ROOT_INO) {
575 if (!dir_emit_dots(file, ctx))
576 goto out;
577 if (ctx->pos == 2) {
578 fake_offset = 1;
579 cpos = 0;
580 }
581 }
582 if (cpos & (sizeof(struct msdos_dir_entry) - 1)) {
583 ret = -ENOENT;
584 goto out;
585 }
586
587 bh = NULL;
588 get_new:
589 if (fat_get_entry(inode, &cpos, &bh, &de) == -1)
590 goto end_of_dir;
591 parse_record:
592 nr_slots = 0;
593 /*
594 * Check for long filename entry, but if short_only, we don't
595 * need to parse long filename.
596 */
597 if (isvfat && !short_only) {
598 if (de->name[0] == DELETED_FLAG)
599 goto record_end;
600 if (de->attr != ATTR_EXT && (de->attr & ATTR_VOLUME))
601 goto record_end;
602 if (de->attr != ATTR_EXT && IS_FREE(de->name))
603 goto record_end;
604 } else {
605 if ((de->attr & ATTR_VOLUME) || IS_FREE(de->name))
606 goto record_end;
607 }
608
609 if (isvfat && de->attr == ATTR_EXT) {
610 int status = fat_parse_long(inode, &cpos, &bh, &de,
611 &unicode, &nr_slots);
612 if (status < 0) {
613 bh = NULL;
614 ret = status;
615 goto end_of_dir;
616 } else if (status == PARSE_INVALID)
617 goto record_end;
618 else if (status == PARSE_NOT_LONGNAME)
619 goto parse_record;
620 else if (status == PARSE_EOF)
621 goto end_of_dir;
622
623 if (nr_slots) {
624 void *longname = unicode + FAT_MAX_UNI_CHARS;
625 int size = PATH_MAX - FAT_MAX_UNI_SIZE;
626 int len = fat_uni_to_x8(sb, unicode, longname, size);
627
628 fill_name = longname;
629 fill_len = len;
630 /* !both && !short_only, so we don't need shortname. */
631 if (!both)
632 goto start_filldir;
633
634 short_len = fat_parse_short(sb, de, bufname,
635 sbi->options.dotsOK);
636 if (short_len == 0)
637 goto record_end;
638 /* hack for fat_ioctl_filldir() */
639 both->longname = fill_name;
640 both->long_len = fill_len;
641 both->shortname = bufname;
642 both->short_len = short_len;
643 fill_name = NULL;
644 fill_len = 0;
645 goto start_filldir;
646 }
647 }
648
649 short_len = fat_parse_short(sb, de, bufname, sbi->options.dotsOK);
650 if (short_len == 0)
651 goto record_end;
652
653 fill_name = bufname;
654 fill_len = short_len;
655
656 start_filldir:
657 ctx->pos = cpos - (nr_slots + 1) * sizeof(struct msdos_dir_entry);
658 if (fake_offset && ctx->pos < 2)
659 ctx->pos = 2;
660
661 if (!memcmp(de->name, MSDOS_DOT, MSDOS_NAME)) {
662 if (!dir_emit_dot(file, ctx))
663 goto fill_failed;
664 } else if (!memcmp(de->name, MSDOS_DOTDOT, MSDOS_NAME)) {
665 if (!dir_emit_dotdot(file, ctx))
666 goto fill_failed;
667 } else {
668 unsigned long inum;
669 loff_t i_pos = fat_make_i_pos(sb, bh, de);
670 struct inode *tmp = fat_iget(sb, i_pos);
671 if (tmp) {
672 inum = tmp->i_ino;
673 iput(tmp);
674 } else
675 inum = iunique(sb, MSDOS_ROOT_INO);
676 if (!dir_emit(ctx, fill_name, fill_len, inum,
677 (de->attr & ATTR_DIR) ? DT_DIR : DT_REG))
678 goto fill_failed;
679 }
680
681 record_end:
682 fake_offset = 0;
683 ctx->pos = cpos;
684 goto get_new;
685
686 end_of_dir:
687 if (fake_offset && cpos < 2)
688 ctx->pos = 2;
689 else
690 ctx->pos = cpos;
691 fill_failed:
692 brelse(bh);
693 if (unicode)
694 __putname(unicode);
695 out:
696 mutex_unlock(&sbi->s_lock);
697
698 return ret;
699 }
700
701 static int fat_readdir(struct file *file, struct dir_context *ctx)
702 {
703 return __fat_readdir(file_inode(file), file, ctx, 0, NULL);
704 }
705
706 #define FAT_IOCTL_FILLDIR_FUNC(func, dirent_type) \
707 static int func(struct dir_context *ctx, const char *name, int name_len, \
708 loff_t offset, u64 ino, unsigned int d_type) \
709 { \
710 struct fat_ioctl_filldir_callback *buf = \
711 container_of(ctx, struct fat_ioctl_filldir_callback, ctx); \
712 struct dirent_type __user *d1 = buf->dirent; \
713 struct dirent_type __user *d2 = d1 + 1; \
714 \
715 if (buf->result) \
716 return -EINVAL; \
717 buf->result++; \
718 \
719 if (name != NULL) { \
720 /* dirent has only short name */ \
721 if (name_len >= sizeof(d1->d_name)) \
722 name_len = sizeof(d1->d_name) - 1; \
723 \
724 if (put_user(0, d2->d_name) || \
725 put_user(0, &d2->d_reclen) || \
726 copy_to_user(d1->d_name, name, name_len) || \
727 put_user(0, d1->d_name + name_len) || \
728 put_user(name_len, &d1->d_reclen)) \
729 goto efault; \
730 } else { \
731 /* dirent has short and long name */ \
732 const char *longname = buf->longname; \
733 int long_len = buf->long_len; \
734 const char *shortname = buf->shortname; \
735 int short_len = buf->short_len; \
736 \
737 if (long_len >= sizeof(d1->d_name)) \
738 long_len = sizeof(d1->d_name) - 1; \
739 if (short_len >= sizeof(d1->d_name)) \
740 short_len = sizeof(d1->d_name) - 1; \
741 \
742 if (copy_to_user(d2->d_name, longname, long_len) || \
743 put_user(0, d2->d_name + long_len) || \
744 put_user(long_len, &d2->d_reclen) || \
745 put_user(ino, &d2->d_ino) || \
746 put_user(offset, &d2->d_off) || \
747 copy_to_user(d1->d_name, shortname, short_len) || \
748 put_user(0, d1->d_name + short_len) || \
749 put_user(short_len, &d1->d_reclen)) \
750 goto efault; \
751 } \
752 return 0; \
753 efault: \
754 buf->result = -EFAULT; \
755 return -EFAULT; \
756 }
757
758 FAT_IOCTL_FILLDIR_FUNC(fat_ioctl_filldir, __fat_dirent)
759
760 static int fat_ioctl_readdir(struct inode *inode, struct file *file,
761 void __user *dirent, filldir_t filldir,
762 int short_only, int both)
763 {
764 struct fat_ioctl_filldir_callback buf = {
765 .ctx.actor = filldir,
766 .dirent = dirent
767 };
768 int ret;
769
770 buf.dirent = dirent;
771 buf.result = 0;
772 inode_lock_shared(inode);
773 buf.ctx.pos = file->f_pos;
774 ret = -ENOENT;
775 if (!IS_DEADDIR(inode)) {
776 ret = __fat_readdir(inode, file, &buf.ctx,
777 short_only, both ? &buf : NULL);
778 file->f_pos = buf.ctx.pos;
779 }
780 inode_unlock_shared(inode);
781 if (ret >= 0)
782 ret = buf.result;
783 return ret;
784 }
785
786 static long fat_dir_ioctl(struct file *filp, unsigned int cmd,
787 unsigned long arg)
788 {
789 struct inode *inode = file_inode(filp);
790 struct __fat_dirent __user *d1 = (struct __fat_dirent __user *)arg;
791 int short_only, both;
792
793 switch (cmd) {
794 case VFAT_IOCTL_READDIR_SHORT:
795 short_only = 1;
796 both = 0;
797 break;
798 case VFAT_IOCTL_READDIR_BOTH:
799 short_only = 0;
800 both = 1;
801 break;
802 default:
803 return fat_generic_ioctl(filp, cmd, arg);
804 }
805
806 if (!access_ok(VERIFY_WRITE, d1, sizeof(struct __fat_dirent[2])))
807 return -EFAULT;
808 /*
809 * Yes, we don't need this put_user() absolutely. However old
810 * code didn't return the right value. So, app use this value,
811 * in order to check whether it is EOF.
812 */
813 if (put_user(0, &d1->d_reclen))
814 return -EFAULT;
815
816 return fat_ioctl_readdir(inode, filp, d1, fat_ioctl_filldir,
817 short_only, both);
818 }
819
820 #ifdef CONFIG_COMPAT
821 #define VFAT_IOCTL_READDIR_BOTH32 _IOR('r', 1, struct compat_dirent[2])
822 #define VFAT_IOCTL_READDIR_SHORT32 _IOR('r', 2, struct compat_dirent[2])
823
824 FAT_IOCTL_FILLDIR_FUNC(fat_compat_ioctl_filldir, compat_dirent)
825
826 static long fat_compat_dir_ioctl(struct file *filp, unsigned cmd,
827 unsigned long arg)
828 {
829 struct inode *inode = file_inode(filp);
830 struct compat_dirent __user *d1 = compat_ptr(arg);
831 int short_only, both;
832
833 switch (cmd) {
834 case VFAT_IOCTL_READDIR_SHORT32:
835 short_only = 1;
836 both = 0;
837 break;
838 case VFAT_IOCTL_READDIR_BOTH32:
839 short_only = 0;
840 both = 1;
841 break;
842 default:
843 return fat_generic_ioctl(filp, cmd, (unsigned long)arg);
844 }
845
846 if (!access_ok(VERIFY_WRITE, d1, sizeof(struct compat_dirent[2])))
847 return -EFAULT;
848 /*
849 * Yes, we don't need this put_user() absolutely. However old
850 * code didn't return the right value. So, app use this value,
851 * in order to check whether it is EOF.
852 */
853 if (put_user(0, &d1->d_reclen))
854 return -EFAULT;
855
856 return fat_ioctl_readdir(inode, filp, d1, fat_compat_ioctl_filldir,
857 short_only, both);
858 }
859 #endif /* CONFIG_COMPAT */
860
861 const struct file_operations fat_dir_operations = {
862 .llseek = generic_file_llseek,
863 .read = generic_read_dir,
864 .iterate_shared = fat_readdir,
865 .unlocked_ioctl = fat_dir_ioctl,
866 #ifdef CONFIG_COMPAT
867 .compat_ioctl = fat_compat_dir_ioctl,
868 #endif
869 .fsync = fat_file_fsync,
870 };
871
872 static int fat_get_short_entry(struct inode *dir, loff_t *pos,
873 struct buffer_head **bh,
874 struct msdos_dir_entry **de)
875 {
876 while (fat_get_entry(dir, pos, bh, de) >= 0) {
877 /* free entry or long name entry or volume label */
878 if (!IS_FREE((*de)->name) && !((*de)->attr & ATTR_VOLUME))
879 return 0;
880 }
881 return -ENOENT;
882 }
883
884 /*
885 * The ".." entry can not provide the "struct fat_slot_info" information
886 * for inode, nor a usable i_pos. So, this function provides some information
887 * only.
888 *
889 * Since this function walks through the on-disk inodes within a directory,
890 * callers are responsible for taking any locks necessary to prevent the
891 * directory from changing.
892 */
893 int fat_get_dotdot_entry(struct inode *dir, struct buffer_head **bh,
894 struct msdos_dir_entry **de)
895 {
896 loff_t offset = 0;
897
898 *de = NULL;
899 while (fat_get_short_entry(dir, &offset, bh, de) >= 0) {
900 if (!strncmp((*de)->name, MSDOS_DOTDOT, MSDOS_NAME))
901 return 0;
902 }
903 return -ENOENT;
904 }
905 EXPORT_SYMBOL_GPL(fat_get_dotdot_entry);
906
907 /* See if directory is empty */
908 int fat_dir_empty(struct inode *dir)
909 {
910 struct buffer_head *bh;
911 struct msdos_dir_entry *de;
912 loff_t cpos;
913 int result = 0;
914
915 bh = NULL;
916 cpos = 0;
917 while (fat_get_short_entry(dir, &cpos, &bh, &de) >= 0) {
918 if (strncmp(de->name, MSDOS_DOT , MSDOS_NAME) &&
919 strncmp(de->name, MSDOS_DOTDOT, MSDOS_NAME)) {
920 result = -ENOTEMPTY;
921 break;
922 }
923 }
924 brelse(bh);
925 return result;
926 }
927 EXPORT_SYMBOL_GPL(fat_dir_empty);
928
929 /*
930 * fat_subdirs counts the number of sub-directories of dir. It can be run
931 * on directories being created.
932 */
933 int fat_subdirs(struct inode *dir)
934 {
935 struct buffer_head *bh;
936 struct msdos_dir_entry *de;
937 loff_t cpos;
938 int count = 0;
939
940 bh = NULL;
941 cpos = 0;
942 while (fat_get_short_entry(dir, &cpos, &bh, &de) >= 0) {
943 if (de->attr & ATTR_DIR)
944 count++;
945 }
946 brelse(bh);
947 return count;
948 }
949
950 /*
951 * Scans a directory for a given file (name points to its formatted name).
952 * Returns an error code or zero.
953 */
954 int fat_scan(struct inode *dir, const unsigned char *name,
955 struct fat_slot_info *sinfo)
956 {
957 struct super_block *sb = dir->i_sb;
958
959 sinfo->slot_off = 0;
960 sinfo->bh = NULL;
961 while (fat_get_short_entry(dir, &sinfo->slot_off, &sinfo->bh,
962 &sinfo->de) >= 0) {
963 if (!strncmp(sinfo->de->name, name, MSDOS_NAME)) {
964 sinfo->slot_off -= sizeof(*sinfo->de);
965 sinfo->nr_slots = 1;
966 sinfo->i_pos = fat_make_i_pos(sb, sinfo->bh, sinfo->de);
967 return 0;
968 }
969 }
970 return -ENOENT;
971 }
972 EXPORT_SYMBOL_GPL(fat_scan);
973
974 /*
975 * Scans a directory for a given logstart.
976 * Returns an error code or zero.
977 */
978 int fat_scan_logstart(struct inode *dir, int i_logstart,
979 struct fat_slot_info *sinfo)
980 {
981 struct super_block *sb = dir->i_sb;
982
983 sinfo->slot_off = 0;
984 sinfo->bh = NULL;
985 while (fat_get_short_entry(dir, &sinfo->slot_off, &sinfo->bh,
986 &sinfo->de) >= 0) {
987 if (fat_get_start(MSDOS_SB(sb), sinfo->de) == i_logstart) {
988 sinfo->slot_off -= sizeof(*sinfo->de);
989 sinfo->nr_slots = 1;
990 sinfo->i_pos = fat_make_i_pos(sb, sinfo->bh, sinfo->de);
991 return 0;
992 }
993 }
994 return -ENOENT;
995 }
996
997 static int __fat_remove_entries(struct inode *dir, loff_t pos, int nr_slots)
998 {
999 struct super_block *sb = dir->i_sb;
1000 struct buffer_head *bh;
1001 struct msdos_dir_entry *de, *endp;
1002 int err = 0, orig_slots;
1003
1004 while (nr_slots) {
1005 bh = NULL;
1006 if (fat_get_entry(dir, &pos, &bh, &de) < 0) {
1007 err = -EIO;
1008 break;
1009 }
1010
1011 orig_slots = nr_slots;
1012 endp = (struct msdos_dir_entry *)(bh->b_data + sb->s_blocksize);
1013 while (nr_slots && de < endp) {
1014 de->name[0] = DELETED_FLAG;
1015 de++;
1016 nr_slots--;
1017 }
1018 mark_buffer_dirty_inode(bh, dir);
1019 if (IS_DIRSYNC(dir))
1020 err = sync_dirty_buffer(bh);
1021 brelse(bh);
1022 if (err)
1023 break;
1024
1025 /* pos is *next* de's position, so this does `- sizeof(de)' */
1026 pos += ((orig_slots - nr_slots) * sizeof(*de)) - sizeof(*de);
1027 }
1028
1029 return err;
1030 }
1031
1032 int fat_remove_entries(struct inode *dir, struct fat_slot_info *sinfo)
1033 {
1034 struct super_block *sb = dir->i_sb;
1035 struct msdos_dir_entry *de;
1036 struct buffer_head *bh;
1037 int err = 0, nr_slots;
1038
1039 /*
1040 * First stage: Remove the shortname. By this, the directory
1041 * entry is removed.
1042 */
1043 nr_slots = sinfo->nr_slots;
1044 de = sinfo->de;
1045 sinfo->de = NULL;
1046 bh = sinfo->bh;
1047 sinfo->bh = NULL;
1048 while (nr_slots && de >= (struct msdos_dir_entry *)bh->b_data) {
1049 de->name[0] = DELETED_FLAG;
1050 de--;
1051 nr_slots--;
1052 }
1053 mark_buffer_dirty_inode(bh, dir);
1054 if (IS_DIRSYNC(dir))
1055 err = sync_dirty_buffer(bh);
1056 brelse(bh);
1057 if (err)
1058 return err;
1059 dir->i_version++;
1060
1061 if (nr_slots) {
1062 /*
1063 * Second stage: remove the remaining longname slots.
1064 * (This directory entry is already removed, and so return
1065 * the success)
1066 */
1067 err = __fat_remove_entries(dir, sinfo->slot_off, nr_slots);
1068 if (err) {
1069 fat_msg(sb, KERN_WARNING,
1070 "Couldn't remove the long name slots");
1071 }
1072 }
1073
1074 dir->i_mtime = dir->i_atime = current_time(dir);
1075 if (IS_DIRSYNC(dir))
1076 (void)fat_sync_inode(dir);
1077 else
1078 mark_inode_dirty(dir);
1079
1080 return 0;
1081 }
1082 EXPORT_SYMBOL_GPL(fat_remove_entries);
1083
1084 static int fat_zeroed_cluster(struct inode *dir, sector_t blknr, int nr_used,
1085 struct buffer_head **bhs, int nr_bhs)
1086 {
1087 struct super_block *sb = dir->i_sb;
1088 sector_t last_blknr = blknr + MSDOS_SB(sb)->sec_per_clus;
1089 int err, i, n;
1090
1091 /* Zeroing the unused blocks on this cluster */
1092 blknr += nr_used;
1093 n = nr_used;
1094 while (blknr < last_blknr) {
1095 bhs[n] = sb_getblk(sb, blknr);
1096 if (!bhs[n]) {
1097 err = -ENOMEM;
1098 goto error;
1099 }
1100 /* Avoid race with userspace read via bdev */
1101 lock_buffer(bhs[n]);
1102 memset(bhs[n]->b_data, 0, sb->s_blocksize);
1103 set_buffer_uptodate(bhs[n]);
1104 unlock_buffer(bhs[n]);
1105 mark_buffer_dirty_inode(bhs[n], dir);
1106
1107 n++;
1108 blknr++;
1109 if (n == nr_bhs) {
1110 if (IS_DIRSYNC(dir)) {
1111 err = fat_sync_bhs(bhs, n);
1112 if (err)
1113 goto error;
1114 }
1115 for (i = 0; i < n; i++)
1116 brelse(bhs[i]);
1117 n = 0;
1118 }
1119 }
1120 if (IS_DIRSYNC(dir)) {
1121 err = fat_sync_bhs(bhs, n);
1122 if (err)
1123 goto error;
1124 }
1125 for (i = 0; i < n; i++)
1126 brelse(bhs[i]);
1127
1128 return 0;
1129
1130 error:
1131 for (i = 0; i < n; i++)
1132 bforget(bhs[i]);
1133 return err;
1134 }
1135
1136 int fat_alloc_new_dir(struct inode *dir, struct timespec *ts)
1137 {
1138 struct super_block *sb = dir->i_sb;
1139 struct msdos_sb_info *sbi = MSDOS_SB(sb);
1140 struct buffer_head *bhs[MAX_BUF_PER_PAGE];
1141 struct msdos_dir_entry *de;
1142 sector_t blknr;
1143 __le16 date, time;
1144 u8 time_cs;
1145 int err, cluster;
1146
1147 err = fat_alloc_clusters(dir, &cluster, 1);
1148 if (err)
1149 goto error;
1150
1151 blknr = fat_clus_to_blknr(sbi, cluster);
1152 bhs[0] = sb_getblk(sb, blknr);
1153 if (!bhs[0]) {
1154 err = -ENOMEM;
1155 goto error_free;
1156 }
1157
1158 fat_time_unix2fat(sbi, ts, &time, &date, &time_cs);
1159
1160 de = (struct msdos_dir_entry *)bhs[0]->b_data;
1161 /* Avoid race with userspace read via bdev */
1162 lock_buffer(bhs[0]);
1163 /* filling the new directory slots ("." and ".." entries) */
1164 memcpy(de[0].name, MSDOS_DOT, MSDOS_NAME);
1165 memcpy(de[1].name, MSDOS_DOTDOT, MSDOS_NAME);
1166 de->attr = de[1].attr = ATTR_DIR;
1167 de[0].lcase = de[1].lcase = 0;
1168 de[0].time = de[1].time = time;
1169 de[0].date = de[1].date = date;
1170 if (sbi->options.isvfat) {
1171 /* extra timestamps */
1172 de[0].ctime = de[1].ctime = time;
1173 de[0].ctime_cs = de[1].ctime_cs = time_cs;
1174 de[0].adate = de[0].cdate = de[1].adate = de[1].cdate = date;
1175 } else {
1176 de[0].ctime = de[1].ctime = 0;
1177 de[0].ctime_cs = de[1].ctime_cs = 0;
1178 de[0].adate = de[0].cdate = de[1].adate = de[1].cdate = 0;
1179 }
1180 fat_set_start(&de[0], cluster);
1181 fat_set_start(&de[1], MSDOS_I(dir)->i_logstart);
1182 de[0].size = de[1].size = 0;
1183 memset(de + 2, 0, sb->s_blocksize - 2 * sizeof(*de));
1184 set_buffer_uptodate(bhs[0]);
1185 unlock_buffer(bhs[0]);
1186 mark_buffer_dirty_inode(bhs[0], dir);
1187
1188 err = fat_zeroed_cluster(dir, blknr, 1, bhs, MAX_BUF_PER_PAGE);
1189 if (err)
1190 goto error_free;
1191
1192 return cluster;
1193
1194 error_free:
1195 fat_free_clusters(dir, cluster);
1196 error:
1197 return err;
1198 }
1199 EXPORT_SYMBOL_GPL(fat_alloc_new_dir);
1200
1201 static int fat_add_new_entries(struct inode *dir, void *slots, int nr_slots,
1202 int *nr_cluster, struct msdos_dir_entry **de,
1203 struct buffer_head **bh, loff_t *i_pos)
1204 {
1205 struct super_block *sb = dir->i_sb;
1206 struct msdos_sb_info *sbi = MSDOS_SB(sb);
1207 struct buffer_head *bhs[MAX_BUF_PER_PAGE];
1208 sector_t blknr, start_blknr, last_blknr;
1209 unsigned long size, copy;
1210 int err, i, n, offset, cluster[2];
1211
1212 /*
1213 * The minimum cluster size is 512bytes, and maximum entry
1214 * size is 32*slots (672bytes). So, iff the cluster size is
1215 * 512bytes, we may need two clusters.
1216 */
1217 size = nr_slots * sizeof(struct msdos_dir_entry);
1218 *nr_cluster = (size + (sbi->cluster_size - 1)) >> sbi->cluster_bits;
1219 BUG_ON(*nr_cluster > 2);
1220
1221 err = fat_alloc_clusters(dir, cluster, *nr_cluster);
1222 if (err)
1223 goto error;
1224
1225 /*
1226 * First stage: Fill the directory entry. NOTE: This cluster
1227 * is not referenced from any inode yet, so updates order is
1228 * not important.
1229 */
1230 i = n = copy = 0;
1231 do {
1232 start_blknr = blknr = fat_clus_to_blknr(sbi, cluster[i]);
1233 last_blknr = start_blknr + sbi->sec_per_clus;
1234 while (blknr < last_blknr) {
1235 bhs[n] = sb_getblk(sb, blknr);
1236 if (!bhs[n]) {
1237 err = -ENOMEM;
1238 goto error_nomem;
1239 }
1240
1241 /* fill the directory entry */
1242 copy = min(size, sb->s_blocksize);
1243 /* Avoid race with userspace read via bdev */
1244 lock_buffer(bhs[n]);
1245 memcpy(bhs[n]->b_data, slots, copy);
1246 set_buffer_uptodate(bhs[n]);
1247 unlock_buffer(bhs[n]);
1248 mark_buffer_dirty_inode(bhs[n], dir);
1249 slots += copy;
1250 size -= copy;
1251 if (!size)
1252 break;
1253 n++;
1254 blknr++;
1255 }
1256 } while (++i < *nr_cluster);
1257
1258 memset(bhs[n]->b_data + copy, 0, sb->s_blocksize - copy);
1259 offset = copy - sizeof(struct msdos_dir_entry);
1260 get_bh(bhs[n]);
1261 *bh = bhs[n];
1262 *de = (struct msdos_dir_entry *)((*bh)->b_data + offset);
1263 *i_pos = fat_make_i_pos(sb, *bh, *de);
1264
1265 /* Second stage: clear the rest of cluster, and write outs */
1266 err = fat_zeroed_cluster(dir, start_blknr, ++n, bhs, MAX_BUF_PER_PAGE);
1267 if (err)
1268 goto error_free;
1269
1270 return cluster[0];
1271
1272 error_free:
1273 brelse(*bh);
1274 *bh = NULL;
1275 n = 0;
1276 error_nomem:
1277 for (i = 0; i < n; i++)
1278 bforget(bhs[i]);
1279 fat_free_clusters(dir, cluster[0]);
1280 error:
1281 return err;
1282 }
1283
1284 int fat_add_entries(struct inode *dir, void *slots, int nr_slots,
1285 struct fat_slot_info *sinfo)
1286 {
1287 struct super_block *sb = dir->i_sb;
1288 struct msdos_sb_info *sbi = MSDOS_SB(sb);
1289 struct buffer_head *bh, *prev, *bhs[3]; /* 32*slots (672bytes) */
1290 struct msdos_dir_entry *uninitialized_var(de);
1291 int err, free_slots, i, nr_bhs;
1292 loff_t pos, i_pos;
1293
1294 sinfo->nr_slots = nr_slots;
1295
1296 /* First stage: search free directory entries */
1297 free_slots = nr_bhs = 0;
1298 bh = prev = NULL;
1299 pos = 0;
1300 err = -ENOSPC;
1301 while (fat_get_entry(dir, &pos, &bh, &de) > -1) {
1302 /* check the maximum size of directory */
1303 if (pos >= FAT_MAX_DIR_SIZE)
1304 goto error;
1305
1306 if (IS_FREE(de->name)) {
1307 if (prev != bh) {
1308 get_bh(bh);
1309 bhs[nr_bhs] = prev = bh;
1310 nr_bhs++;
1311 }
1312 free_slots++;
1313 if (free_slots == nr_slots)
1314 goto found;
1315 } else {
1316 for (i = 0; i < nr_bhs; i++)
1317 brelse(bhs[i]);
1318 prev = NULL;
1319 free_slots = nr_bhs = 0;
1320 }
1321 }
1322 if (dir->i_ino == MSDOS_ROOT_INO) {
1323 if (sbi->fat_bits != 32)
1324 goto error;
1325 } else if (MSDOS_I(dir)->i_start == 0) {
1326 fat_msg(sb, KERN_ERR, "Corrupted directory (i_pos %lld)",
1327 MSDOS_I(dir)->i_pos);
1328 err = -EIO;
1329 goto error;
1330 }
1331
1332 found:
1333 err = 0;
1334 pos -= free_slots * sizeof(*de);
1335 nr_slots -= free_slots;
1336 if (free_slots) {
1337 /*
1338 * Second stage: filling the free entries with new entries.
1339 * NOTE: If this slots has shortname, first, we write
1340 * the long name slots, then write the short name.
1341 */
1342 int size = free_slots * sizeof(*de);
1343 int offset = pos & (sb->s_blocksize - 1);
1344 int long_bhs = nr_bhs - (nr_slots == 0);
1345
1346 /* Fill the long name slots. */
1347 for (i = 0; i < long_bhs; i++) {
1348 int copy = min_t(int, sb->s_blocksize - offset, size);
1349 memcpy(bhs[i]->b_data + offset, slots, copy);
1350 mark_buffer_dirty_inode(bhs[i], dir);
1351 offset = 0;
1352 slots += copy;
1353 size -= copy;
1354 }
1355 if (long_bhs && IS_DIRSYNC(dir))
1356 err = fat_sync_bhs(bhs, long_bhs);
1357 if (!err && i < nr_bhs) {
1358 /* Fill the short name slot. */
1359 int copy = min_t(int, sb->s_blocksize - offset, size);
1360 memcpy(bhs[i]->b_data + offset, slots, copy);
1361 mark_buffer_dirty_inode(bhs[i], dir);
1362 if (IS_DIRSYNC(dir))
1363 err = sync_dirty_buffer(bhs[i]);
1364 }
1365 for (i = 0; i < nr_bhs; i++)
1366 brelse(bhs[i]);
1367 if (err)
1368 goto error_remove;
1369 }
1370
1371 if (nr_slots) {
1372 int cluster, nr_cluster;
1373
1374 /*
1375 * Third stage: allocate the cluster for new entries.
1376 * And initialize the cluster with new entries, then
1377 * add the cluster to dir.
1378 */
1379 cluster = fat_add_new_entries(dir, slots, nr_slots, &nr_cluster,
1380 &de, &bh, &i_pos);
1381 if (cluster < 0) {
1382 err = cluster;
1383 goto error_remove;
1384 }
1385 err = fat_chain_add(dir, cluster, nr_cluster);
1386 if (err) {
1387 fat_free_clusters(dir, cluster);
1388 goto error_remove;
1389 }
1390 if (dir->i_size & (sbi->cluster_size - 1)) {
1391 fat_fs_error(sb, "Odd directory size");
1392 dir->i_size = (dir->i_size + sbi->cluster_size - 1)
1393 & ~((loff_t)sbi->cluster_size - 1);
1394 }
1395 dir->i_size += nr_cluster << sbi->cluster_bits;
1396 MSDOS_I(dir)->mmu_private += nr_cluster << sbi->cluster_bits;
1397 }
1398 sinfo->slot_off = pos;
1399 sinfo->de = de;
1400 sinfo->bh = bh;
1401 sinfo->i_pos = fat_make_i_pos(sb, sinfo->bh, sinfo->de);
1402
1403 return 0;
1404
1405 error:
1406 brelse(bh);
1407 for (i = 0; i < nr_bhs; i++)
1408 brelse(bhs[i]);
1409 return err;
1410
1411 error_remove:
1412 brelse(bh);
1413 if (free_slots)
1414 __fat_remove_entries(dir, pos, free_slots);
1415 return err;
1416 }
1417 EXPORT_SYMBOL_GPL(fat_add_entries);
Linux with added FPC-III support