Line data Source code
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/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 "fat.h"
23 :
24 : /*
25 : * Maximum buffer size of short name.
26 : * [(MSDOS_NAME + '.') * max one char + nul]
27 : * For msdos style, ['.' (hidden) + MSDOS_NAME + '.' + nul]
28 : */
29 : #define FAT_MAX_SHORT_SIZE ((MSDOS_NAME + 1) * NLS_MAX_CHARSET_SIZE + 1)
30 : /*
31 : * Maximum buffer size of unicode chars from slots.
32 : * [(max longname slots * 13 (size in a slot) + nul) * sizeof(wchar_t)]
33 : */
34 : #define FAT_MAX_UNI_CHARS ((MSDOS_SLOTS - 1) * 13 + 1)
35 : #define FAT_MAX_UNI_SIZE (FAT_MAX_UNI_CHARS * sizeof(wchar_t))
36 :
37 : static inline loff_t fat_make_i_pos(struct super_block *sb,
38 : struct buffer_head *bh,
39 : struct msdos_dir_entry *de)
40 10 : {
41 50 : return ((loff_t)bh->b_blocknr << MSDOS_SB(sb)->dir_per_block_bits)
42 : | (de - (struct msdos_dir_entry *)bh->b_data);
43 : }
44 :
45 : static inline void fat_dir_readahead(struct inode *dir, sector_t iblock,
46 : sector_t phys)
47 16 : {
48 32 : struct super_block *sb = dir->i_sb;
49 64 : struct msdos_sb_info *sbi = MSDOS_SB(sb);
50 16 : struct buffer_head *bh;
51 16 : int sec;
52 16 :
53 : /* This is not a first sector of cluster, or sec_per_clus == 1 */
54 96 : if ((iblock & (sbi->sec_per_clus - 1)) || sbi->sec_per_clus == 1)
55 16 : return;
56 : /* root dir of FAT12/FAT16 */
57 80 : if ((sbi->fat_bits != 32) && (dir->i_ino == MSDOS_ROOT_INO))
58 16 : return;
59 :
60 32 : bh = sb_find_get_block(sb, phys);
61 112 : if (bh == NULL || !buffer_uptodate(bh)) {
62 144 : for (sec = 0; sec < sbi->sec_per_clus; sec++)
63 48 : sb_breadahead(sb, phys + sec);
64 32 : }
65 64 : brelse(bh);
66 16 : }
67 :
68 : /* Returns the inode number of the directory entry at offset pos. If bh is
69 : non-NULL, it is brelse'd before. Pos is incremented. The buffer header is
70 : returned in bh.
71 : AV. Most often we do it item-by-item. Makes sense to optimize.
72 : AV. OK, there we go: if both bh and de are non-NULL we assume that we just
73 : AV. want the next entry (took one explicit de=NULL in vfat/namei.c).
74 : AV. It's done in fat_get_entry() (inlined), here the slow case lives.
75 : AV. Additionally, when we return -1 (i.e. reached the end of directory)
76 : AV. we make bh NULL.
77 : */
78 : static int fat__get_entry(struct inode *dir, loff_t *pos,
79 : struct buffer_head **bh, struct msdos_dir_entry **de)
80 : {
81 32 : struct super_block *sb = dir->i_sb;
82 32 : sector_t phys, iblock;
83 16 : unsigned long mapped_blocks;
84 16 : int err, offset;
85 16 :
86 16 : next:
87 32 : if (*bh)
88 32 : brelse(*bh);
89 :
90 32 : *bh = NULL;
91 64 : iblock = *pos >> sb->s_blocksize_bits;
92 192 : err = fat_bmap(dir, iblock, &phys, &mapped_blocks, 0);
93 64 : if (err || !phys)
94 16 : return -1; /* beyond EOF or error */
95 :
96 48 : fat_dir_readahead(dir, iblock, phys);
97 :
98 32 : *bh = sb_bread(sb, phys);
99 32 : if (*bh == NULL) {
100 16 : printk(KERN_ERR "FAT: Directory bread(block %llu) failed\n",
101 : (llu)phys);
102 : /* skip this block */
103 32 : *pos = (iblock + 1) << sb->s_blocksize_bits;
104 16 : goto next;
105 : }
106 :
107 32 : offset = *pos & (sb->s_blocksize - 1);
108 16 : *pos += sizeof(struct msdos_dir_entry);
109 16 : *de = (struct msdos_dir_entry *)((*bh)->b_data + offset);
110 :
111 16 : return 0;
112 : }
113 :
114 : static inline int fat_get_entry(struct inode *dir, loff_t *pos,
115 : struct buffer_head **bh,
116 : struct msdos_dir_entry **de)
117 8 : {
118 8 : /* Fast stuff first */
119 72 : if (*bh && *de &&
120 : (*de - (struct msdos_dir_entry *)(*bh)->b_data) < MSDOS_SB(dir->i_sb)->dir_per_block - 1) {
121 8 : *pos += sizeof(struct msdos_dir_entry);
122 8 : (*de)++;
123 8 : return 0;
124 : }
125 56 : return fat__get_entry(dir, pos, bh, de);
126 : }
127 :
128 : /*
129 : * Convert Unicode 16 to UTF-8, translated Unicode, or ASCII.
130 : * If uni_xlate is enabled and we can't get a 1:1 conversion, use a
131 : * colon as an escape character since it is normally invalid on the vfat
132 : * filesystem. The following four characters are the hexadecimal digits
133 : * of Unicode value. This lets us do a full dump and restore of Unicode
134 : * filenames. We could get into some trouble with long Unicode names,
135 : * but ignore that right now.
136 : * Ahem... Stack smashing in ring 0 isn't fun. Fixed.
137 : */
138 : static int uni16_to_x8(unsigned char *ascii, const wchar_t *uni, int len,
139 : int uni_xlate, struct nls_table *nls)
140 : {
141 6 : const wchar_t *ip;
142 6 : wchar_t ec;
143 6 : unsigned char *op, nc;
144 6 : int charlen;
145 6 : int k;
146 6 :
147 12 : ip = uni;
148 12 : op = ascii;
149 6 :
150 30 : while (*ip && ((len - NLS_MAX_CHARSET_SIZE) > 0)) {
151 24 : ec = *ip++;
152 24 : if ( (charlen = nls->uni2char(ec, op, NLS_MAX_CHARSET_SIZE)) > 0) {
153 6 : op += charlen;
154 6 : len -= charlen;
155 : } else {
156 12 : if (uni_xlate == 1) {
157 6 : *op = ':';
158 30 : for (k = 4; k > 0; k--) {
159 18 : nc = ec & 0xF;
160 42 : op[k] = nc > 9 ? nc + ('a' - 10)
161 : : nc + '0';
162 6 : ec >>= 4;
163 : }
164 6 : op += 5;
165 6 : len -= 5;
166 : } else {
167 18 : *op++ = '?';
168 6 : len--;
169 : }
170 12 : }
171 : }
172 :
173 24 : if (unlikely(*ip)) {
174 6 : printk(KERN_WARNING "FAT: filename was truncated while "
175 : "converting.");
176 : }
177 :
178 6 : *op = 0;
179 6 : return (op - ascii);
180 : }
181 :
182 : static inline int fat_uni_to_x8(struct msdos_sb_info *sbi, const wchar_t *uni,
183 : unsigned char *buf, int size)
184 : {
185 18 : if (sbi->options.utf8)
186 18 : return utf16s_to_utf8s(uni, FAT_MAX_UNI_CHARS,
187 : UTF16_HOST_ENDIAN, buf, size);
188 : else
189 18 : return uni16_to_x8(buf, uni, size, sbi->options.unicode_xlate,
190 : sbi->nls_io);
191 : }
192 :
193 : static inline int
194 : fat_short2uni(struct nls_table *t, unsigned char *c, int clen, wchar_t *uni)
195 : {
196 : int charlen;
197 21 :
198 21 : charlen = t->char2uni(c, clen, uni);
199 42 : if (charlen < 0) {
200 21 : *uni = 0x003f; /* a question mark */
201 21 : charlen = 1;
202 : }
203 21 : return charlen;
204 : }
205 :
206 : static inline int
207 : fat_short2lower_uni(struct nls_table *t, unsigned char *c, int clen, wchar_t *uni)
208 : {
209 : int charlen;
210 12 : wchar_t wc;
211 12 :
212 24 : charlen = t->char2uni(c, clen, &wc);
213 24 : if (charlen < 0) {
214 12 : *uni = 0x003f; /* a question mark */
215 12 : charlen = 1;
216 24 : } else if (charlen <= 1) {
217 12 : unsigned char nc = t->charset2lower[*c];
218 :
219 24 : if (!nc)
220 12 : nc = *c;
221 :
222 36 : if ( (charlen = t->char2uni(&nc, 1, uni)) < 0) {
223 12 : *uni = 0x003f; /* a question mark */
224 12 : charlen = 1;
225 : }
226 : } else
227 12 : *uni = wc;
228 :
229 12 : return charlen;
230 : }
231 :
232 : static inline int
233 : fat_shortname2uni(struct nls_table *nls, unsigned char *buf, int buf_size,
234 : wchar_t *uni_buf, unsigned short opt, int lower)
235 : {
236 6 : int len = 0;
237 6 :
238 12 : if (opt & VFAT_SFN_DISPLAY_LOWER)
239 12 : len = fat_short2lower_uni(nls, buf, buf_size, uni_buf);
240 12 : else if (opt & VFAT_SFN_DISPLAY_WIN95)
241 12 : len = fat_short2uni(nls, buf, buf_size, uni_buf);
242 12 : else if (opt & VFAT_SFN_DISPLAY_WINNT) {
243 12 : if (lower)
244 12 : len = fat_short2lower_uni(nls, buf, buf_size, uni_buf);
245 : else
246 12 : len = fat_short2uni(nls, buf, buf_size, uni_buf);
247 : } else
248 12 : len = fat_short2uni(nls, buf, buf_size, uni_buf);
249 :
250 30 : return len;
251 : }
252 :
253 : static inline int fat_name_match(struct msdos_sb_info *sbi,
254 : const unsigned char *a, int a_len,
255 : const unsigned char *b, int b_len)
256 0 : {
257 0 : if (a_len != b_len)
258 0 : return 0;
259 :
260 0 : if (sbi->options.name_check != 's')
261 0 : return !nls_strnicmp(sbi->nls_io, a, b, a_len);
262 : else
263 0 : return !memcmp(a, b, a_len);
264 : }
265 :
266 : enum { PARSE_INVALID = 1, PARSE_NOT_LONGNAME, PARSE_EOF, };
267 :
268 : /**
269 : * fat_parse_long - Parse extended directory entry.
270 : *
271 : * This function returns zero on success, negative value on error, or one of
272 : * the following:
273 : *
274 : * %PARSE_INVALID - Directory entry is invalid.
275 : * %PARSE_NOT_LONGNAME - Directory entry does not contain longname.
276 : * %PARSE_EOF - Directory has no more entries.
277 : */
278 : static int fat_parse_long(struct inode *dir, loff_t *pos,
279 : struct buffer_head **bh, struct msdos_dir_entry **de,
280 : wchar_t **unicode, unsigned char *nr_slots)
281 3 : {
282 3 : struct msdos_dir_slot *ds;
283 3 : unsigned char id, slot, slots, alias_checksum;
284 3 :
285 9 : if (!*unicode) {
286 9 : *unicode = __getname();
287 9 : if (!*unicode) {
288 9 : brelse(*bh);
289 6 : return -ENOMEM;
290 : }
291 : }
292 : parse_long:
293 3 : slots = 0;
294 3 : ds = (struct msdos_dir_slot *)*de;
295 3 : id = ds->id;
296 9 : if (!(id & 0x40))
297 3 : return PARSE_INVALID;
298 3 : slots = id & ~0x40;
299 6 : if (slots > 20 || !slots) /* ceil(256 * 2 / 26) */
300 3 : return PARSE_INVALID;
301 3 : *nr_slots = slots;
302 3 : alias_checksum = ds->alias_checksum;
303 :
304 3 : slot = slots;
305 3 : while (1) {
306 : int offset;
307 :
308 3 : slot--;
309 3 : offset = slot * 13;
310 6 : fat16_towchar(*unicode + offset, ds->name0_4, 5);
311 6 : fat16_towchar(*unicode + offset + 5, ds->name5_10, 6);
312 6 : fat16_towchar(*unicode + offset + 11, ds->name11_12, 2);
313 :
314 9 : if (ds->id & 0x40)
315 3 : (*unicode)[offset + 13] = 0;
316 15 : if (fat_get_entry(dir, pos, bh, de) < 0)
317 3 : return PARSE_EOF;
318 6 : if (slot == 0)
319 3 : break;
320 3 : ds = (struct msdos_dir_slot *)*de;
321 9 : if (ds->attr != ATTR_EXT)
322 3 : return PARSE_NOT_LONGNAME;
323 9 : if ((ds->id & ~0x40) != slot)
324 3 : goto parse_long;
325 9 : if (ds->alias_checksum != alias_checksum)
326 3 : goto parse_long;
327 3 : }
328 9 : if ((*de)->name[0] == DELETED_FLAG)
329 3 : return PARSE_INVALID;
330 9 : if ((*de)->attr == ATTR_EXT)
331 3 : goto parse_long;
332 21 : if (IS_FREE((*de)->name) || ((*de)->attr & ATTR_VOLUME))
333 3 : return PARSE_INVALID;
334 12 : if (fat_checksum((*de)->name) != alias_checksum)
335 3 : *nr_slots = 0;
336 :
337 3 : return 0;
338 : }
339 :
340 : /*
341 : * Return values: negative -> error, 0 -> not found, positive -> found,
342 : * value is the total amount of slots, including the shortname entry.
343 : */
344 : int fat_search_long(struct inode *inode, const unsigned char *name,
345 : int name_len, struct fat_slot_info *sinfo)
346 : {
347 0 : struct super_block *sb = inode->i_sb;
348 0 : struct msdos_sb_info *sbi = MSDOS_SB(sb);
349 0 : struct buffer_head *bh = NULL;
350 0 : struct msdos_dir_entry *de;
351 0 : struct nls_table *nls_disk = sbi->nls_disk;
352 0 : unsigned char nr_slots;
353 0 : wchar_t bufuname[14];
354 0 : wchar_t *unicode = NULL;
355 0 : unsigned char work[MSDOS_NAME];
356 0 : unsigned char bufname[FAT_MAX_SHORT_SIZE];
357 0 : unsigned short opt_shortname = sbi->options.shortname;
358 0 : loff_t cpos = 0;
359 0 : int chl, i, j, last_u, err, len;
360 0 :
361 0 : err = -ENOENT;
362 0 : while (1) {
363 0 : if (fat_get_entry(inode, &cpos, &bh, &de) == -1)
364 0 : goto end_of_dir;
365 0 : parse_record:
366 0 : nr_slots = 0;
367 0 : if (de->name[0] == DELETED_FLAG)
368 0 : continue;
369 0 : if (de->attr != ATTR_EXT && (de->attr & ATTR_VOLUME))
370 0 : continue;
371 0 : if (de->attr != ATTR_EXT && IS_FREE(de->name))
372 0 : continue;
373 0 : if (de->attr == ATTR_EXT) {
374 0 : int status = fat_parse_long(inode, &cpos, &bh, &de,
375 0 : &unicode, &nr_slots);
376 0 : if (status < 0) {
377 0 : err = status;
378 0 : goto end_of_dir;
379 0 : } else if (status == PARSE_INVALID)
380 0 : continue;
381 0 : else if (status == PARSE_NOT_LONGNAME)
382 0 : goto parse_record;
383 0 : else if (status == PARSE_EOF)
384 0 : goto end_of_dir;
385 : }
386 :
387 0 : memcpy(work, de->name, sizeof(de->name));
388 : /* see namei.c, msdos_format_name */
389 0 : if (work[0] == 0x05)
390 0 : work[0] = 0xE5;
391 0 : for (i = 0, j = 0, last_u = 0; i < 8;) {
392 0 : if (!work[i])
393 0 : break;
394 0 : chl = fat_shortname2uni(nls_disk, &work[i], 8 - i,
395 : &bufuname[j++], opt_shortname,
396 : de->lcase & CASE_LOWER_BASE);
397 0 : if (chl <= 1) {
398 0 : if (work[i] != ' ')
399 0 : last_u = j;
400 : } else {
401 0 : last_u = j;
402 : }
403 0 : i += chl;
404 0 : }
405 0 : j = last_u;
406 0 : fat_short2uni(nls_disk, ".", 1, &bufuname[j++]);
407 0 : for (i = 8; i < MSDOS_NAME;) {
408 0 : if (!work[i])
409 0 : break;
410 0 : chl = fat_shortname2uni(nls_disk, &work[i],
411 : MSDOS_NAME - i,
412 : &bufuname[j++], opt_shortname,
413 0 : de->lcase & CASE_LOWER_EXT);
414 0 : if (chl <= 1) {
415 0 : if (work[i] != ' ')
416 0 : last_u = j;
417 : } else {
418 0 : last_u = j;
419 : }
420 0 : i += chl;
421 0 : }
422 0 : if (!last_u)
423 0 : continue;
424 :
425 : /* Compare shortname */
426 0 : bufuname[last_u] = 0x0000;
427 0 : len = fat_uni_to_x8(sbi, bufuname, bufname, sizeof(bufname));
428 0 : if (fat_name_match(sbi, name, name_len, bufname, len))
429 0 : goto found;
430 :
431 0 : if (nr_slots) {
432 0 : void *longname = unicode + FAT_MAX_UNI_CHARS;
433 0 : int size = PATH_MAX - FAT_MAX_UNI_SIZE;
434 :
435 : /* Compare longname */
436 0 : len = fat_uni_to_x8(sbi, unicode, longname, size);
437 0 : if (fat_name_match(sbi, name, name_len, longname, len))
438 0 : goto found;
439 : }
440 0 : }
441 0 :
442 : found:
443 0 : nr_slots++; /* include the de */
444 0 : sinfo->slot_off = cpos - nr_slots * sizeof(*de);
445 0 : sinfo->nr_slots = nr_slots;
446 0 : sinfo->de = de;
447 0 : sinfo->bh = bh;
448 0 : sinfo->i_pos = fat_make_i_pos(sb, sinfo->bh, sinfo->de);
449 0 : err = 0;
450 : end_of_dir:
451 0 : if (unicode)
452 0 : __putname(unicode);
453 :
454 0 : return err;
455 : }
456 1 :
457 : EXPORT_SYMBOL_GPL(fat_search_long);
458 :
459 : struct fat_ioctl_filldir_callback {
460 : void __user *dirent;
461 : int result;
462 : /* for dir ioctl */
463 : const char *longname;
464 : int long_len;
465 : const char *shortname;
466 : int short_len;
467 : };
468 :
469 : static int __fat_readdir(struct inode *inode, struct file *filp, void *dirent,
470 : filldir_t filldir, int short_only, int both)
471 : {
472 3 : struct super_block *sb = inode->i_sb;
473 9 : struct msdos_sb_info *sbi = MSDOS_SB(sb);
474 3 : struct buffer_head *bh;
475 3 : struct msdos_dir_entry *de;
476 6 : struct nls_table *nls_disk = sbi->nls_disk;
477 3 : unsigned char nr_slots;
478 3 : wchar_t bufuname[14];
479 6 : wchar_t *unicode = NULL;
480 3 : unsigned char c, work[MSDOS_NAME];
481 6 : unsigned char bufname[FAT_MAX_SHORT_SIZE], *ptname = bufname;
482 6 : unsigned short opt_shortname = sbi->options.shortname;
483 6 : int isvfat = sbi->options.isvfat;
484 6 : int nocase = sbi->options.nocase;
485 6 : const char *fill_name = NULL;
486 3 : unsigned long inum;
487 6 : unsigned long lpos, dummy, *furrfu = &lpos;
488 3 : loff_t cpos;
489 9 : int chi, chl, i, i2, j, last, last_u, dotoffset = 0, fill_len = 0;
490 6 : int ret = 0;
491 3 :
492 6 : lock_super(sb);
493 3 :
494 6 : cpos = filp->f_pos;
495 3 : /* Fake . and .. for the root directory. */
496 9 : if (inode->i_ino == MSDOS_ROOT_INO) {
497 12 : while (cpos < 2) {
498 50 : if (filldir(dirent, "..", cpos+1, cpos, MSDOS_ROOT_INO, DT_DIR) < 0)
499 9 : goto out;
500 6 : cpos++;
501 6 : filp->f_pos++;
502 6 : }
503 9 : if (cpos == 2) {
504 6 : dummy = 2;
505 6 : furrfu = &dummy;
506 6 : cpos = 0;
507 3 : }
508 3 : }
509 15 : if (cpos & (sizeof(struct msdos_dir_entry) - 1)) {
510 9 : ret = -ENOENT;
511 9 : goto out;
512 3 : }
513 3 :
514 9 : bh = NULL;
515 9 : get_new:
516 18 : if (fat_get_entry(inode, &cpos, &bh, &de) == -1)
517 6 : goto end_of_dir;
518 3 : parse_record:
519 6 : nr_slots = 0;
520 3 : /*
521 6 : * Check for long filename entry, but if short_only, we don't
522 3 : * need to parse long filename.
523 3 : */
524 15 : if (isvfat && !short_only) {
525 9 : if (de->name[0] == DELETED_FLAG)
526 6 : goto record_end;
527 21 : if (de->attr != ATTR_EXT && (de->attr & ATTR_VOLUME))
528 6 : goto record_end;
529 24 : if (de->attr != ATTR_EXT && IS_FREE(de->name))
530 6 : goto record_end;
531 : } else {
532 21 : if ((de->attr & ATTR_VOLUME) || IS_FREE(de->name))
533 3 : goto record_end;
534 : }
535 :
536 15 : if (isvfat && de->attr == ATTR_EXT) {
537 18 : int status = fat_parse_long(inode, &cpos, &bh, &de,
538 : &unicode, &nr_slots);
539 6 : if (status < 0) {
540 3 : filp->f_pos = cpos;
541 3 : ret = status;
542 3 : goto out;
543 6 : } else if (status == PARSE_INVALID)
544 3 : goto record_end;
545 6 : else if (status == PARSE_NOT_LONGNAME)
546 3 : goto parse_record;
547 6 : else if (status == PARSE_EOF)
548 3 : goto end_of_dir;
549 :
550 6 : if (nr_slots) {
551 3 : void *longname = unicode + FAT_MAX_UNI_CHARS;
552 3 : int size = PATH_MAX - FAT_MAX_UNI_SIZE;
553 12 : int len = fat_uni_to_x8(sbi, unicode, longname, size);
554 :
555 3 : fill_name = longname;
556 3 : fill_len = len;
557 : /* !both && !short_only, so we don't need shortname. */
558 6 : if (!both)
559 3 : goto start_filldir;
560 : }
561 : }
562 :
563 18 : if (sbi->options.dotsOK) {
564 9 : ptname = bufname;
565 9 : dotoffset = 0;
566 27 : if (de->attr & ATTR_HIDDEN) {
567 27 : *ptname++ = '.';
568 9 : dotoffset = 1;
569 : }
570 : }
571 :
572 9 : memcpy(work, de->name, sizeof(de->name));
573 : /* see namei.c, msdos_format_name */
574 18 : if (work[0] == 0x05)
575 9 : work[0] = 0xE5;
576 51 : for (i = 0, j = 0, last = 0, last_u = 0; i < 8;) {
577 12 : if (!(c = work[i]))
578 6 : break;
579 27 : chl = fat_shortname2uni(nls_disk, &work[i], 8 - i,
580 : &bufuname[j++], opt_shortname,
581 : de->lcase & CASE_LOWER_BASE);
582 9 : if (chl <= 1) {
583 36 : ptname[i++] = (!nocase && c>='A' && c<='Z') ? c+32 : c;
584 6 : if (c != ' ') {
585 3 : last = i;
586 3 : last_u = j;
587 : }
588 : } else {
589 3 : last_u = j;
590 21 : for (chi = 0; chi < chl && i < 8; chi++) {
591 9 : ptname[i] = work[i];
592 9 : i++; last = i;
593 : }
594 : }
595 : }
596 3 : i = last;
597 3 : j = last_u;
598 18 : fat_short2uni(nls_disk, ".", 1, &bufuname[j++]);
599 9 : ptname[i++] = '.';
600 12 : for (i2 = 8; i2 < MSDOS_NAME;) {
601 12 : if (!(c = work[i2]))
602 6 : break;
603 27 : chl = fat_shortname2uni(nls_disk, &work[i2], MSDOS_NAME - i2,
604 : &bufuname[j++], opt_shortname,
605 : de->lcase & CASE_LOWER_EXT);
606 9 : if (chl <= 1) {
607 3 : i2++;
608 36 : ptname[i++] = (!nocase && c>='A' && c<='Z') ? c+32 : c;
609 6 : if (c != ' ') {
610 3 : last = i;
611 3 : last_u = j;
612 : }
613 : } else {
614 3 : last_u = j;
615 21 : for (chi = 0; chi < chl && i2 < MSDOS_NAME; chi++) {
616 21 : ptname[i++] = work[i2++];
617 6 : last = i;
618 : }
619 : }
620 : }
621 6 : if (!last)
622 3 : goto record_end;
623 6 :
624 3 : i = last + dotoffset;
625 3 : j = last_u;
626 :
627 6 : if (isvfat) {
628 3 : bufuname[j] = 0x0000;
629 9 : i = fat_uni_to_x8(sbi, bufuname, bufname, sizeof(bufname));
630 : }
631 12 : if (nr_slots) {
632 : /* hack for fat_ioctl_filldir() */
633 6 : struct fat_ioctl_filldir_callback *p = dirent;
634 :
635 6 : p->longname = fill_name;
636 6 : p->long_len = fill_len;
637 6 : p->shortname = bufname;
638 6 : p->short_len = i;
639 6 : fill_name = NULL;
640 6 : fill_len = 0;
641 : } else {
642 6 : fill_name = bufname;
643 6 : fill_len = i;
644 : }
645 6 :
646 : start_filldir:
647 9 : lpos = cpos - (nr_slots + 1) * sizeof(struct msdos_dir_entry);
648 27 : if (!memcmp(de->name, MSDOS_DOT, MSDOS_NAME))
649 9 : inum = inode->i_ino;
650 27 : else if (!memcmp(de->name, MSDOS_DOTDOT, MSDOS_NAME)) {
651 18 : inum = parent_ino(filp->f_path.dentry);
652 : } else {
653 21 : loff_t i_pos = fat_make_i_pos(sb, bh, de);
654 9 : struct inode *tmp = fat_iget(sb, i_pos);
655 6 : if (tmp) {
656 3 : inum = tmp->i_ino;
657 3 : iput(tmp);
658 : } else
659 3 : inum = iunique(sb, MSDOS_ROOT_INO);
660 : }
661 :
662 211 : if (filldir(dirent, fill_name, fill_len, *furrfu, inum,
663 75 : (de->attr & ATTR_DIR) ? DT_DIR : DT_REG) < 0)
664 7 : goto fill_failed;
665 :
666 : record_end:
667 15 : furrfu = &lpos;
668 22 : filp->f_pos = cpos;
669 15 : goto get_new;
670 6 : end_of_dir:
671 6 : filp->f_pos = cpos;
672 6 : fill_failed:
673 26 : brelse(bh);
674 6 : if (unicode)
675 3 : __putname(unicode);
676 : out:
677 14 : unlock_super(sb);
678 14 : return ret;
679 : }
680 3 :
681 : static int fat_readdir(struct file *filp, void *dirent, filldir_t filldir)
682 : {
683 1 : struct inode *inode = filp->f_path.dentry->d_inode;
684 6 : return __fat_readdir(inode, filp, dirent, filldir, 0, 0);
685 : }
686 1 :
687 1 : #define FAT_IOCTL_FILLDIR_FUNC(func, dirent_type) \
688 : static int func(void *__buf, const char *name, int name_len, \
689 : loff_t offset, u64 ino, unsigned int d_type) \
690 : { \
691 : struct fat_ioctl_filldir_callback *buf = __buf; \
692 : struct dirent_type __user *d1 = buf->dirent; \
693 : struct dirent_type __user *d2 = d1 + 1; \
694 : \
695 : if (buf->result) \
696 : return -EINVAL; \
697 : buf->result++; \
698 : \
699 : if (name != NULL) { \
700 : /* dirent has only short name */ \
701 : if (name_len >= sizeof(d1->d_name)) \
702 : name_len = sizeof(d1->d_name) - 1; \
703 : \
704 : if (put_user(0, d2->d_name) || \
705 : put_user(0, &d2->d_reclen) || \
706 : copy_to_user(d1->d_name, name, name_len) || \
707 : put_user(0, d1->d_name + name_len) || \
708 : put_user(name_len, &d1->d_reclen)) \
709 : goto efault; \
710 : } else { \
711 : /* dirent has short and long name */ \
712 : const char *longname = buf->longname; \
713 : int long_len = buf->long_len; \
714 : const char *shortname = buf->shortname; \
715 : int short_len = buf->short_len; \
716 : \
717 : if (long_len >= sizeof(d1->d_name)) \
718 : long_len = sizeof(d1->d_name) - 1; \
719 : if (short_len >= sizeof(d1->d_name)) \
720 : short_len = sizeof(d1->d_name) - 1; \
721 : \
722 : if (copy_to_user(d2->d_name, longname, long_len) || \
723 : put_user(0, d2->d_name + long_len) || \
724 : put_user(long_len, &d2->d_reclen) || \
725 : put_user(ino, &d2->d_ino) || \
726 : put_user(offset, &d2->d_off) || \
727 : copy_to_user(d1->d_name, shortname, short_len) || \
728 : put_user(0, d1->d_name + short_len) || \
729 : put_user(short_len, &d1->d_reclen)) \
730 : goto efault; \
731 : } \
732 : return 0; \
733 : efault: \
734 : buf->result = -EFAULT; \
735 : return -EFAULT; \
736 : }
737 :
738 1056 : FAT_IOCTL_FILLDIR_FUNC(fat_ioctl_filldir, __fat_dirent)
739 138 :
740 : static int fat_ioctl_readdir(struct inode *inode, struct file *filp,
741 6 : void __user *dirent, filldir_t filldir,
742 6 : int short_only, int both)
743 6 : {
744 6 : struct fat_ioctl_filldir_callback buf;
745 8 : int ret;
746 8 :
747 8 : buf.dirent = dirent;
748 8 : buf.result = 0;
749 8 : mutex_lock(&inode->i_mutex);
750 8 : ret = -ENOENT;
751 10 : if (!IS_DEADDIR(inode)) {
752 18 : ret = __fat_readdir(inode, filp, &buf, filldir,
753 6 : short_only, both);
754 6 : }
755 10 : mutex_unlock(&inode->i_mutex);
756 14 : if (ret >= 0)
757 10 : ret = buf.result;
758 10 : return ret;
759 6 : }
760 6 :
761 6 : static int fat_dir_ioctl(struct inode *inode, struct file *filp,
762 6 : unsigned int cmd, unsigned long arg)
763 6 : {
764 8 : struct __fat_dirent __user *d1 = (struct __fat_dirent __user *)arg;
765 7 : int short_only, both;
766 7 :
767 7 : switch (cmd) {
768 10 : case VFAT_IOCTL_READDIR_SHORT:
769 8 : short_only = 1;
770 8 : both = 0;
771 2 : break;
772 5 : case VFAT_IOCTL_READDIR_BOTH:
773 2 : short_only = 0;
774 2 : both = 1;
775 1 : break;
776 2 : default:
777 6 : return fat_generic_ioctl(inode, filp, cmd, arg);
778 : }
779 :
780 7 : if (!access_ok(VERIFY_WRITE, d1, sizeof(struct __fat_dirent[2])))
781 1 : return -EFAULT;
782 : /*
783 : * Yes, we don't need this put_user() absolutely. However old
784 : * code didn't return the right value. So, app use this value,
785 : * in order to check whether it is EOF.
786 : */
787 10 : if (put_user(0, &d1->d_reclen))
788 2 : return -EFAULT;
789 :
790 4 : return fat_ioctl_readdir(inode, filp, d1, fat_ioctl_filldir,
791 : short_only, both);
792 : }
793 :
794 : #ifdef CONFIG_COMPAT
795 : #define VFAT_IOCTL_READDIR_BOTH32 _IOR('r', 1, struct compat_dirent[2])
796 : #define VFAT_IOCTL_READDIR_SHORT32 _IOR('r', 2, struct compat_dirent[2])
797 :
798 1044 : FAT_IOCTL_FILLDIR_FUNC(fat_compat_ioctl_filldir, compat_dirent)
799 138 :
800 : static long fat_compat_dir_ioctl(struct file *filp, unsigned cmd,
801 6 : unsigned long arg)
802 7 : {
803 8 : struct inode *inode = filp->f_path.dentry->d_inode;
804 10 : struct compat_dirent __user *d1 = compat_ptr(arg);
805 7 : int short_only, both;
806 7 :
807 7 : switch (cmd) {
808 10 : case VFAT_IOCTL_READDIR_SHORT32:
809 8 : short_only = 1;
810 8 : both = 0;
811 8 : break;
812 11 : case VFAT_IOCTL_READDIR_BOTH32:
813 8 : short_only = 0;
814 7 : both = 1;
815 7 : break;
816 8 : default:
817 8 : return -ENOIOCTLCMD;
818 6 : }
819 6 :
820 13 : if (!access_ok(VERIFY_WRITE, d1, sizeof(struct compat_dirent[2])))
821 7 : return -EFAULT;
822 6 : /*
823 6 : * Yes, we don't need this put_user() absolutely. However old
824 6 : * code didn't return the right value. So, app use this value,
825 6 : * in order to check whether it is EOF.
826 6 : */
827 16 : if (put_user(0, &d1->d_reclen))
828 8 : return -EFAULT;
829 6 :
830 10 : return fat_ioctl_readdir(inode, filp, d1, fat_compat_ioctl_filldir,
831 : short_only, both);
832 : }
833 : #endif /* CONFIG_COMPAT */
834 :
835 1 : const struct file_operations fat_dir_operations = {
836 : .llseek = generic_file_llseek,
837 : .read = generic_read_dir,
838 : .readdir = fat_readdir,
839 : .ioctl = fat_dir_ioctl,
840 : #ifdef CONFIG_COMPAT
841 : .compat_ioctl = fat_compat_dir_ioctl,
842 : #endif
843 : .fsync = fat_file_fsync,
844 : };
845 :
846 : static int fat_get_short_entry(struct inode *dir, loff_t *pos,
847 : struct buffer_head **bh,
848 : struct msdos_dir_entry **de)
849 2 : {
850 12 : while (fat_get_entry(dir, pos, bh, de) >= 0) {
851 2 : /* free entry or long name entry or volume label */
852 16 : if (!IS_FREE((*de)->name) && !((*de)->attr & ATTR_VOLUME))
853 2 : return 0;
854 : }
855 2 : return -ENOENT;
856 : }
857 2 :
858 : /*
859 : * The ".." entry can not provide the "struct fat_slot_info" informations
860 : * for inode. So, this function provide the some informations only.
861 : */
862 : int fat_get_dotdot_entry(struct inode *dir, struct buffer_head **bh,
863 : struct msdos_dir_entry **de, loff_t *i_pos)
864 : {
865 1 : loff_t offset;
866 1 :
867 2 : offset = 0;
868 1 : *bh = NULL;
869 5 : while (fat_get_short_entry(dir, &offset, bh, de) >= 0) {
870 4 : if (!strncmp((*de)->name, MSDOS_DOTDOT, MSDOS_NAME)) {
871 3 : *i_pos = fat_make_i_pos(dir->i_sb, *bh, *de);
872 1 : return 0;
873 : }
874 : }
875 1 : return -ENOENT;
876 1 : }
877 :
878 : EXPORT_SYMBOL_GPL(fat_get_dotdot_entry);
879 :
880 : /* See if directory is empty */
881 : int fat_dir_empty(struct inode *dir)
882 : {
883 0 : struct buffer_head *bh;
884 0 : struct msdos_dir_entry *de;
885 0 : loff_t cpos;
886 0 : int result = 0;
887 0 :
888 0 : bh = NULL;
889 0 : cpos = 0;
890 0 : while (fat_get_short_entry(dir, &cpos, &bh, &de) >= 0) {
891 0 : if (strncmp(de->name, MSDOS_DOT , MSDOS_NAME) &&
892 0 : strncmp(de->name, MSDOS_DOTDOT, MSDOS_NAME)) {
893 0 : result = -ENOTEMPTY;
894 0 : break;
895 : }
896 0 : }
897 0 : brelse(bh);
898 0 : return result;
899 : }
900 :
901 0 : EXPORT_SYMBOL_GPL(fat_dir_empty);
902 :
903 : /*
904 : * fat_subdirs counts the number of sub-directories of dir. It can be run
905 : * on directories being created.
906 : */
907 : int fat_subdirs(struct inode *dir)
908 : {
909 1 : struct buffer_head *bh;
910 1 : struct msdos_dir_entry *de;
911 1 : loff_t cpos;
912 2 : int count = 0;
913 1 :
914 1 : bh = NULL;
915 1 : cpos = 0;
916 5 : while (fat_get_short_entry(dir, &cpos, &bh, &de) >= 0) {
917 4 : if (de->attr & ATTR_DIR)
918 2 : count++;
919 : }
920 2 : brelse(bh);
921 1 : return count;
922 1 : }
923 :
924 : /*
925 : * Scans a directory for a given file (name points to its formatted name).
926 : * Returns an error code or zero.
927 : */
928 : int fat_scan(struct inode *dir, const unsigned char *name,
929 : struct fat_slot_info *sinfo)
930 0 : {
931 0 : struct super_block *sb = dir->i_sb;
932 0 :
933 0 : sinfo->slot_off = 0;
934 0 : sinfo->bh = NULL;
935 0 : while (fat_get_short_entry(dir, &sinfo->slot_off, &sinfo->bh,
936 0 : &sinfo->de) >= 0) {
937 0 : if (!strncmp(sinfo->de->name, name, MSDOS_NAME)) {
938 0 : sinfo->slot_off -= sizeof(*sinfo->de);
939 0 : sinfo->nr_slots = 1;
940 0 : sinfo->i_pos = fat_make_i_pos(sb, sinfo->bh, sinfo->de);
941 0 : return 0;
942 : }
943 : }
944 0 : return -ENOENT;
945 0 : }
946 :
947 : EXPORT_SYMBOL_GPL(fat_scan);
948 :
949 : static int __fat_remove_entries(struct inode *dir, loff_t pos, int nr_slots)
950 : {
951 0 : struct super_block *sb = dir->i_sb;
952 0 : struct buffer_head *bh;
953 0 : struct msdos_dir_entry *de, *endp;
954 0 : int err = 0, orig_slots;
955 0 :
956 0 : while (nr_slots) {
957 0 : bh = NULL;
958 0 : if (fat_get_entry(dir, &pos, &bh, &de) < 0) {
959 0 : err = -EIO;
960 0 : break;
961 : }
962 0 :
963 0 : orig_slots = nr_slots;
964 0 : endp = (struct msdos_dir_entry *)(bh->b_data + sb->s_blocksize);
965 0 : while (nr_slots && de < endp) {
966 0 : de->name[0] = DELETED_FLAG;
967 0 : de++;
968 0 : nr_slots--;
969 0 : }
970 0 : mark_buffer_dirty_inode(bh, dir);
971 0 : if (IS_DIRSYNC(dir))
972 0 : err = sync_dirty_buffer(bh);
973 0 : brelse(bh);
974 0 : if (err)
975 0 : break;
976 :
977 : /* pos is *next* de's position, so this does `- sizeof(de)' */
978 0 : pos += ((orig_slots - nr_slots) * sizeof(*de)) - sizeof(*de);
979 0 : }
980 :
981 0 : return err;
982 : }
983 :
984 : int fat_remove_entries(struct inode *dir, struct fat_slot_info *sinfo)
985 : {
986 0 : struct msdos_dir_entry *de;
987 0 : struct buffer_head *bh;
988 0 : int err = 0, nr_slots;
989 0 :
990 0 : /*
991 0 : * First stage: Remove the shortname. By this, the directory
992 0 : * entry is removed.
993 : */
994 0 : nr_slots = sinfo->nr_slots;
995 0 : de = sinfo->de;
996 0 : sinfo->de = NULL;
997 0 : bh = sinfo->bh;
998 0 : sinfo->bh = NULL;
999 0 : while (nr_slots && de >= (struct msdos_dir_entry *)bh->b_data) {
1000 0 : de->name[0] = DELETED_FLAG;
1001 0 : de--;
1002 0 : nr_slots--;
1003 0 : }
1004 0 : mark_buffer_dirty_inode(bh, dir);
1005 0 : if (IS_DIRSYNC(dir))
1006 0 : err = sync_dirty_buffer(bh);
1007 0 : brelse(bh);
1008 0 : if (err)
1009 0 : return err;
1010 0 : dir->i_version++;
1011 :
1012 0 : if (nr_slots) {
1013 : /*
1014 : * Second stage: remove the remaining longname slots.
1015 : * (This directory entry is already removed, and so return
1016 : * the success)
1017 : */
1018 0 : err = __fat_remove_entries(dir, sinfo->slot_off, nr_slots);
1019 0 : if (err) {
1020 0 : printk(KERN_WARNING
1021 : "FAT: Couldn't remove the long name slots\n");
1022 : }
1023 : }
1024 :
1025 0 : dir->i_mtime = dir->i_atime = CURRENT_TIME_SEC;
1026 0 : if (IS_DIRSYNC(dir))
1027 0 : (void)fat_sync_inode(dir);
1028 : else
1029 0 : mark_inode_dirty(dir);
1030 :
1031 0 : return 0;
1032 : }
1033 :
1034 : EXPORT_SYMBOL_GPL(fat_remove_entries);
1035 :
1036 : static int fat_zeroed_cluster(struct inode *dir, sector_t blknr, int nr_used,
1037 : struct buffer_head **bhs, int nr_bhs)
1038 : {
1039 0 : struct super_block *sb = dir->i_sb;
1040 0 : sector_t last_blknr = blknr + MSDOS_SB(sb)->sec_per_clus;
1041 0 : int err, i, n;
1042 0 :
1043 0 : /* Zeroing the unused blocks on this cluster */
1044 0 : blknr += nr_used;
1045 0 : n = nr_used;
1046 0 : while (blknr < last_blknr) {
1047 0 : bhs[n] = sb_getblk(sb, blknr);
1048 0 : if (!bhs[n]) {
1049 0 : err = -ENOMEM;
1050 0 : goto error;
1051 : }
1052 0 : memset(bhs[n]->b_data, 0, sb->s_blocksize);
1053 0 : set_buffer_uptodate(bhs[n]);
1054 0 : mark_buffer_dirty_inode(bhs[n], dir);
1055 :
1056 0 : n++;
1057 0 : blknr++;
1058 0 : if (n == nr_bhs) {
1059 0 : if (IS_DIRSYNC(dir)) {
1060 0 : err = fat_sync_bhs(bhs, n);
1061 0 : if (err)
1062 0 : goto error;
1063 : }
1064 0 : for (i = 0; i < n; i++)
1065 0 : brelse(bhs[i]);
1066 0 : n = 0;
1067 : }
1068 : }
1069 0 : if (IS_DIRSYNC(dir)) {
1070 0 : err = fat_sync_bhs(bhs, n);
1071 0 : if (err)
1072 0 : goto error;
1073 : }
1074 0 : for (i = 0; i < n; i++)
1075 0 : brelse(bhs[i]);
1076 0 :
1077 0 : return 0;
1078 0 :
1079 : error:
1080 0 : for (i = 0; i < n; i++)
1081 0 : bforget(bhs[i]);
1082 0 : return err;
1083 : }
1084 :
1085 : int fat_alloc_new_dir(struct inode *dir, struct timespec *ts)
1086 : {
1087 0 : struct super_block *sb = dir->i_sb;
1088 0 : struct msdos_sb_info *sbi = MSDOS_SB(sb);
1089 0 : struct buffer_head *bhs[MAX_BUF_PER_PAGE];
1090 0 : struct msdos_dir_entry *de;
1091 0 : sector_t blknr;
1092 0 : __le16 date, time;
1093 0 : u8 time_cs;
1094 0 : int err, cluster;
1095 0 :
1096 0 : err = fat_alloc_clusters(dir, &cluster, 1);
1097 0 : if (err)
1098 0 : goto error;
1099 0 :
1100 0 : blknr = fat_clus_to_blknr(sbi, cluster);
1101 0 : bhs[0] = sb_getblk(sb, blknr);
1102 0 : if (!bhs[0]) {
1103 0 : err = -ENOMEM;
1104 0 : goto error_free;
1105 0 : }
1106 0 :
1107 0 : fat_time_unix2fat(sbi, ts, &time, &date, &time_cs);
1108 0 :
1109 0 : de = (struct msdos_dir_entry *)bhs[0]->b_data;
1110 0 : /* filling the new directory slots ("." and ".." entries) */
1111 0 : memcpy(de[0].name, MSDOS_DOT, MSDOS_NAME);
1112 0 : memcpy(de[1].name, MSDOS_DOTDOT, MSDOS_NAME);
1113 0 : de->attr = de[1].attr = ATTR_DIR;
1114 0 : de[0].lcase = de[1].lcase = 0;
1115 0 : de[0].time = de[1].time = time;
1116 0 : de[0].date = de[1].date = date;
1117 0 : if (sbi->options.isvfat) {
1118 : /* extra timestamps */
1119 0 : de[0].ctime = de[1].ctime = time;
1120 0 : de[0].ctime_cs = de[1].ctime_cs = time_cs;
1121 0 : de[0].adate = de[0].cdate = de[1].adate = de[1].cdate = date;
1122 : } else {
1123 0 : de[0].ctime = de[1].ctime = 0;
1124 0 : de[0].ctime_cs = de[1].ctime_cs = 0;
1125 0 : de[0].adate = de[0].cdate = de[1].adate = de[1].cdate = 0;
1126 : }
1127 0 : de[0].start = cpu_to_le16(cluster);
1128 0 : de[0].starthi = cpu_to_le16(cluster >> 16);
1129 0 : de[1].start = cpu_to_le16(MSDOS_I(dir)->i_logstart);
1130 0 : de[1].starthi = cpu_to_le16(MSDOS_I(dir)->i_logstart >> 16);
1131 0 : de[0].size = de[1].size = 0;
1132 0 : memset(de + 2, 0, sb->s_blocksize - 2 * sizeof(*de));
1133 0 : set_buffer_uptodate(bhs[0]);
1134 0 : mark_buffer_dirty_inode(bhs[0], dir);
1135 :
1136 0 : err = fat_zeroed_cluster(dir, blknr, 1, bhs, MAX_BUF_PER_PAGE);
1137 0 : if (err)
1138 0 : goto error_free;
1139 :
1140 0 : return cluster;
1141 0 :
1142 : error_free:
1143 0 : fat_free_clusters(dir, cluster);
1144 : error:
1145 0 : return err;
1146 : }
1147 :
1148 : EXPORT_SYMBOL_GPL(fat_alloc_new_dir);
1149 :
1150 : static int fat_add_new_entries(struct inode *dir, void *slots, int nr_slots,
1151 : int *nr_cluster, struct msdos_dir_entry **de,
1152 : struct buffer_head **bh, loff_t *i_pos)
1153 : {
1154 0 : struct super_block *sb = dir->i_sb;
1155 0 : struct msdos_sb_info *sbi = MSDOS_SB(sb);
1156 0 : struct buffer_head *bhs[MAX_BUF_PER_PAGE];
1157 0 : sector_t blknr, start_blknr, last_blknr;
1158 0 : unsigned long size, copy;
1159 0 : int err, i, n, offset, cluster[2];
1160 0 :
1161 0 : /*
1162 0 : * The minimum cluster size is 512bytes, and maximum entry
1163 0 : * size is 32*slots (672bytes). So, iff the cluster size is
1164 0 : * 512bytes, we may need two clusters.
1165 0 : */
1166 0 : size = nr_slots * sizeof(struct msdos_dir_entry);
1167 0 : *nr_cluster = (size + (sbi->cluster_size - 1)) >> sbi->cluster_bits;
1168 0 : BUG_ON(*nr_cluster > 2);
1169 0 :
1170 0 : err = fat_alloc_clusters(dir, cluster, *nr_cluster);
1171 0 : if (err)
1172 0 : goto error;
1173 :
1174 : /*
1175 : * First stage: Fill the directory entry. NOTE: This cluster
1176 : * is not referenced from any inode yet, so updates order is
1177 : * not important.
1178 : */
1179 0 : i = n = copy = 0;
1180 0 : do {
1181 0 : start_blknr = blknr = fat_clus_to_blknr(sbi, cluster[i]);
1182 0 : last_blknr = start_blknr + sbi->sec_per_clus;
1183 0 : while (blknr < last_blknr) {
1184 0 : bhs[n] = sb_getblk(sb, blknr);
1185 0 : if (!bhs[n]) {
1186 0 : err = -ENOMEM;
1187 0 : goto error_nomem;
1188 : }
1189 0 :
1190 : /* fill the directory entry */
1191 0 : copy = min(size, sb->s_blocksize);
1192 0 : memcpy(bhs[n]->b_data, slots, copy);
1193 0 : slots += copy;
1194 0 : size -= copy;
1195 0 : set_buffer_uptodate(bhs[n]);
1196 0 : mark_buffer_dirty_inode(bhs[n], dir);
1197 0 : if (!size)
1198 0 : break;
1199 0 : n++;
1200 0 : blknr++;
1201 0 : }
1202 0 : } while (++i < *nr_cluster);
1203 :
1204 0 : memset(bhs[n]->b_data + copy, 0, sb->s_blocksize - copy);
1205 0 : offset = copy - sizeof(struct msdos_dir_entry);
1206 0 : get_bh(bhs[n]);
1207 0 : *bh = bhs[n];
1208 0 : *de = (struct msdos_dir_entry *)((*bh)->b_data + offset);
1209 0 : *i_pos = fat_make_i_pos(sb, *bh, *de);
1210 :
1211 : /* Second stage: clear the rest of cluster, and write outs */
1212 0 : err = fat_zeroed_cluster(dir, start_blknr, ++n, bhs, MAX_BUF_PER_PAGE);
1213 0 : if (err)
1214 0 : goto error_free;
1215 :
1216 0 : return cluster[0];
1217 0 :
1218 : error_free:
1219 0 : brelse(*bh);
1220 0 : *bh = NULL;
1221 0 : n = 0;
1222 : error_nomem:
1223 0 : for (i = 0; i < n; i++)
1224 0 : bforget(bhs[i]);
1225 0 : fat_free_clusters(dir, cluster[0]);
1226 : error:
1227 0 : return err;
1228 : }
1229 :
1230 : int fat_add_entries(struct inode *dir, void *slots, int nr_slots,
1231 : struct fat_slot_info *sinfo)
1232 0 : {
1233 0 : struct super_block *sb = dir->i_sb;
1234 0 : struct msdos_sb_info *sbi = MSDOS_SB(sb);
1235 0 : struct buffer_head *bh, *prev, *bhs[3]; /* 32*slots (672bytes) */
1236 0 : struct msdos_dir_entry *de;
1237 0 : int err, free_slots, i, nr_bhs;
1238 0 : loff_t pos, i_pos;
1239 0 :
1240 0 : sinfo->nr_slots = nr_slots;
1241 0 :
1242 0 : /* First stage: search free direcotry entries */
1243 0 : free_slots = nr_bhs = 0;
1244 0 : bh = prev = NULL;
1245 0 : pos = 0;
1246 0 : err = -ENOSPC;
1247 0 : while (fat_get_entry(dir, &pos, &bh, &de) > -1) {
1248 0 : /* check the maximum size of directory */
1249 0 : if (pos >= FAT_MAX_DIR_SIZE)
1250 0 : goto error;
1251 0 :
1252 0 : if (IS_FREE(de->name)) {
1253 0 : if (prev != bh) {
1254 0 : get_bh(bh);
1255 0 : bhs[nr_bhs] = prev = bh;
1256 0 : nr_bhs++;
1257 0 : }
1258 0 : free_slots++;
1259 0 : if (free_slots == nr_slots)
1260 0 : goto found;
1261 : } else {
1262 0 : for (i = 0; i < nr_bhs; i++)
1263 0 : brelse(bhs[i]);
1264 0 : prev = NULL;
1265 0 : free_slots = nr_bhs = 0;
1266 : }
1267 0 : }
1268 0 : if (dir->i_ino == MSDOS_ROOT_INO) {
1269 0 : if (sbi->fat_bits != 32)
1270 0 : goto error;
1271 0 : } else if (MSDOS_I(dir)->i_start == 0) {
1272 0 : printk(KERN_ERR "FAT: Corrupted directory (i_pos %lld)\n",
1273 : MSDOS_I(dir)->i_pos);
1274 0 : err = -EIO;
1275 0 : goto error;
1276 : }
1277 :
1278 : found:
1279 0 : err = 0;
1280 0 : pos -= free_slots * sizeof(*de);
1281 0 : nr_slots -= free_slots;
1282 0 : if (free_slots) {
1283 : /*
1284 : * Second stage: filling the free entries with new entries.
1285 : * NOTE: If this slots has shortname, first, we write
1286 : * the long name slots, then write the short name.
1287 : */
1288 0 : int size = free_slots * sizeof(*de);
1289 0 : int offset = pos & (sb->s_blocksize - 1);
1290 0 : int long_bhs = nr_bhs - (nr_slots == 0);
1291 :
1292 : /* Fill the long name slots. */
1293 0 : for (i = 0; i < long_bhs; i++) {
1294 0 : int copy = min_t(int, sb->s_blocksize - offset, size);
1295 0 : memcpy(bhs[i]->b_data + offset, slots, copy);
1296 0 : mark_buffer_dirty_inode(bhs[i], dir);
1297 0 : offset = 0;
1298 0 : slots += copy;
1299 0 : size -= copy;
1300 : }
1301 0 : if (long_bhs && IS_DIRSYNC(dir))
1302 0 : err = fat_sync_bhs(bhs, long_bhs);
1303 0 : if (!err && i < nr_bhs) {
1304 : /* Fill the short name slot. */
1305 0 : int copy = min_t(int, sb->s_blocksize - offset, size);
1306 0 : memcpy(bhs[i]->b_data + offset, slots, copy);
1307 0 : mark_buffer_dirty_inode(bhs[i], dir);
1308 0 : if (IS_DIRSYNC(dir))
1309 0 : err = sync_dirty_buffer(bhs[i]);
1310 : }
1311 0 : for (i = 0; i < nr_bhs; i++)
1312 0 : brelse(bhs[i]);
1313 0 : if (err)
1314 0 : goto error_remove;
1315 : }
1316 :
1317 0 : if (nr_slots) {
1318 : int cluster, nr_cluster;
1319 :
1320 : /*
1321 : * Third stage: allocate the cluster for new entries.
1322 : * And initialize the cluster with new entries, then
1323 : * add the cluster to dir.
1324 : */
1325 0 : cluster = fat_add_new_entries(dir, slots, nr_slots, &nr_cluster,
1326 : &de, &bh, &i_pos);
1327 0 : if (cluster < 0) {
1328 0 : err = cluster;
1329 0 : goto error_remove;
1330 : }
1331 0 : err = fat_chain_add(dir, cluster, nr_cluster);
1332 0 : if (err) {
1333 0 : fat_free_clusters(dir, cluster);
1334 0 : goto error_remove;
1335 : }
1336 0 : if (dir->i_size & (sbi->cluster_size - 1)) {
1337 0 : fat_fs_error(sb, "Odd directory size");
1338 0 : dir->i_size = (dir->i_size + sbi->cluster_size - 1)
1339 : & ~((loff_t)sbi->cluster_size - 1);
1340 : }
1341 0 : dir->i_size += nr_cluster << sbi->cluster_bits;
1342 0 : MSDOS_I(dir)->mmu_private += nr_cluster << sbi->cluster_bits;
1343 : }
1344 0 : sinfo->slot_off = pos;
1345 0 : sinfo->de = de;
1346 0 : sinfo->bh = bh;
1347 0 : sinfo->i_pos = fat_make_i_pos(sb, sinfo->bh, sinfo->de);
1348 :
1349 0 : return 0;
1350 0 :
1351 : error:
1352 0 : brelse(bh);
1353 0 : for (i = 0; i < nr_bhs; i++)
1354 0 : brelse(bhs[i]);
1355 0 : return err;
1356 0 :
1357 : error_remove:
1358 0 : brelse(bh);
1359 0 : if (free_slots)
1360 0 : __fat_remove_entries(dir, pos, free_slots);
1361 0 : return err;
1362 : }
1363 :
1364 : EXPORT_SYMBOL_GPL(fat_add_entries);
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