Commit | Line | Data |
---|---|---|
1da177e4 LT |
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> | |
1da177e4 | 19 | #include <linux/buffer_head.h> |
188f83df | 20 | #include <linux/compat.h> |
1da177e4 | 21 | #include <asm/uaccess.h> |
3ed3dec1 | 22 | #include <linux/kernel.h> |
9e975dae | 23 | #include "fat.h" |
1da177e4 | 24 | |
74675a58 AS |
25 | /* |
26 | * Maximum buffer size of short name. | |
27 | * [(MSDOS_NAME + '.') * max one char + nul] | |
28 | * For msdos style, ['.' (hidden) + MSDOS_NAME + '.' + nul] | |
29 | */ | |
30 | #define FAT_MAX_SHORT_SIZE ((MSDOS_NAME + 1) * NLS_MAX_CHARSET_SIZE + 1) | |
31 | /* | |
32 | * Maximum buffer size of unicode chars from slots. | |
33 | * [(max longname slots * 13 (size in a slot) + nul) * sizeof(wchar_t)] | |
34 | */ | |
35 | #define FAT_MAX_UNI_CHARS ((MSDOS_SLOTS - 1) * 13 + 1) | |
36 | #define FAT_MAX_UNI_SIZE (FAT_MAX_UNI_CHARS * sizeof(wchar_t)) | |
37 | ||
deb8274a SM |
38 | static inline unsigned char fat_tolower(unsigned char c) |
39 | { | |
40 | return ((c >= 'A') && (c <= 'Z')) ? c+32 : c; | |
41 | } | |
42 | ||
1da177e4 LT |
43 | static inline loff_t fat_make_i_pos(struct super_block *sb, |
44 | struct buffer_head *bh, | |
45 | struct msdos_dir_entry *de) | |
46 | { | |
47 | return ((loff_t)bh->b_blocknr << MSDOS_SB(sb)->dir_per_block_bits) | |
48 | | (de - (struct msdos_dir_entry *)bh->b_data); | |
49 | } | |
50 | ||
f3ef6f63 KW |
51 | static inline void fat_dir_readahead(struct inode *dir, sector_t iblock, |
52 | sector_t phys) | |
53 | { | |
54 | struct super_block *sb = dir->i_sb; | |
55 | struct msdos_sb_info *sbi = MSDOS_SB(sb); | |
56 | struct buffer_head *bh; | |
57 | int sec; | |
58 | ||
59 | /* This is not a first sector of cluster, or sec_per_clus == 1 */ | |
60 | if ((iblock & (sbi->sec_per_clus - 1)) || sbi->sec_per_clus == 1) | |
61 | return; | |
62 | /* root dir of FAT12/FAT16 */ | |
63 | if ((sbi->fat_bits != 32) && (dir->i_ino == MSDOS_ROOT_INO)) | |
64 | return; | |
65 | ||
83b7c996 OH |
66 | bh = sb_find_get_block(sb, phys); |
67 | if (bh == NULL || !buffer_uptodate(bh)) { | |
f3ef6f63 KW |
68 | for (sec = 0; sec < sbi->sec_per_clus; sec++) |
69 | sb_breadahead(sb, phys + sec); | |
70 | } | |
71 | brelse(bh); | |
72 | } | |
73 | ||
1da177e4 LT |
74 | /* Returns the inode number of the directory entry at offset pos. If bh is |
75 | non-NULL, it is brelse'd before. Pos is incremented. The buffer header is | |
76 | returned in bh. | |
77 | AV. Most often we do it item-by-item. Makes sense to optimize. | |
78 | AV. OK, there we go: if both bh and de are non-NULL we assume that we just | |
79 | AV. want the next entry (took one explicit de=NULL in vfat/namei.c). | |
80 | AV. It's done in fat_get_entry() (inlined), here the slow case lives. | |
81 | AV. Additionally, when we return -1 (i.e. reached the end of directory) | |
82 | AV. we make bh NULL. | |
83 | */ | |
84 | static int fat__get_entry(struct inode *dir, loff_t *pos, | |
85 | struct buffer_head **bh, struct msdos_dir_entry **de) | |
86 | { | |
87 | struct super_block *sb = dir->i_sb; | |
88 | sector_t phys, iblock; | |
e5174baa OH |
89 | unsigned long mapped_blocks; |
90 | int err, offset; | |
1da177e4 LT |
91 | |
92 | next: | |
93 | if (*bh) | |
94 | brelse(*bh); | |
95 | ||
96 | *bh = NULL; | |
97 | iblock = *pos >> sb->s_blocksize_bits; | |
2bdf67eb | 98 | err = fat_bmap(dir, iblock, &phys, &mapped_blocks, 0); |
1da177e4 LT |
99 | if (err || !phys) |
100 | return -1; /* beyond EOF or error */ | |
101 | ||
f3ef6f63 KW |
102 | fat_dir_readahead(dir, iblock, phys); |
103 | ||
1da177e4 LT |
104 | *bh = sb_bread(sb, phys); |
105 | if (*bh == NULL) { | |
f0aac616 NJ |
106 | fat_msg_ratelimit(sb, KERN_ERR, |
107 | "Directory bread(block %llu) failed", (llu)phys); | |
1da177e4 LT |
108 | /* skip this block */ |
109 | *pos = (iblock + 1) << sb->s_blocksize_bits; | |
110 | goto next; | |
111 | } | |
112 | ||
113 | offset = *pos & (sb->s_blocksize - 1); | |
114 | *pos += sizeof(struct msdos_dir_entry); | |
115 | *de = (struct msdos_dir_entry *)((*bh)->b_data + offset); | |
116 | ||
117 | return 0; | |
118 | } | |
119 | ||
120 | static inline int fat_get_entry(struct inode *dir, loff_t *pos, | |
121 | struct buffer_head **bh, | |
122 | struct msdos_dir_entry **de) | |
123 | { | |
124 | /* Fast stuff first */ | |
125 | if (*bh && *de && | |
126 | (*de - (struct msdos_dir_entry *)(*bh)->b_data) < MSDOS_SB(dir->i_sb)->dir_per_block - 1) { | |
127 | *pos += sizeof(struct msdos_dir_entry); | |
128 | (*de)++; | |
129 | return 0; | |
130 | } | |
131 | return fat__get_entry(dir, pos, bh, de); | |
132 | } | |
133 | ||
134 | /* | |
4de151d8 | 135 | * Convert Unicode 16 to UTF-8, translated Unicode, or ASCII. |
1da177e4 LT |
136 | * If uni_xlate is enabled and we can't get a 1:1 conversion, use a |
137 | * colon as an escape character since it is normally invalid on the vfat | |
138 | * filesystem. The following four characters are the hexadecimal digits | |
139 | * of Unicode value. This lets us do a full dump and restore of Unicode | |
140 | * filenames. We could get into some trouble with long Unicode names, | |
141 | * but ignore that right now. | |
142 | * Ahem... Stack smashing in ring 0 isn't fun. Fixed. | |
143 | */ | |
869f58c0 AF |
144 | static int uni16_to_x8(struct super_block *sb, unsigned char *ascii, |
145 | const wchar_t *uni, int len, struct nls_table *nls) | |
1da177e4 | 146 | { |
869f58c0 | 147 | int uni_xlate = MSDOS_SB(sb)->options.unicode_xlate; |
d6886116 OH |
148 | const wchar_t *ip; |
149 | wchar_t ec; | |
3ed3dec1 | 150 | unsigned char *op; |
1da177e4 | 151 | int charlen; |
1da177e4 LT |
152 | |
153 | ip = uni; | |
154 | op = ascii; | |
155 | ||
f22032ba | 156 | while (*ip && ((len - NLS_MAX_CHARSET_SIZE) > 0)) { |
1da177e4 | 157 | ec = *ip++; |
3ed3dec1 | 158 | if ((charlen = nls->uni2char(ec, op, NLS_MAX_CHARSET_SIZE)) > 0) { |
1da177e4 | 159 | op += charlen; |
f22032ba | 160 | len -= charlen; |
1da177e4 LT |
161 | } else { |
162 | if (uni_xlate == 1) { | |
3ed3dec1 | 163 | *op++ = ':'; |
0a90e0f1 AS |
164 | op = hex_byte_pack(op, ec >> 8); |
165 | op = hex_byte_pack(op, ec); | |
f22032ba | 166 | len -= 5; |
1da177e4 LT |
167 | } else { |
168 | *op++ = '?'; | |
f22032ba | 169 | len--; |
1da177e4 LT |
170 | } |
171 | } | |
1da177e4 | 172 | } |
f22032ba KM |
173 | |
174 | if (unlikely(*ip)) { | |
869f58c0 AF |
175 | fat_msg(sb, KERN_WARNING, "filename was truncated while " |
176 | "converting."); | |
f22032ba KM |
177 | } |
178 | ||
1da177e4 LT |
179 | *op = 0; |
180 | return (op - ascii); | |
181 | } | |
182 | ||
869f58c0 | 183 | static inline int fat_uni_to_x8(struct super_block *sb, const wchar_t *uni, |
d6886116 OH |
184 | unsigned char *buf, int size) |
185 | { | |
869f58c0 | 186 | struct msdos_sb_info *sbi = MSDOS_SB(sb); |
d6886116 | 187 | if (sbi->options.utf8) |
74675a58 AS |
188 | return utf16s_to_utf8s(uni, FAT_MAX_UNI_CHARS, |
189 | UTF16_HOST_ENDIAN, buf, size); | |
d6886116 | 190 | else |
869f58c0 | 191 | return uni16_to_x8(sb, buf, uni, size, sbi->nls_io); |
d6886116 OH |
192 | } |
193 | ||
1da177e4 LT |
194 | static inline int |
195 | fat_short2uni(struct nls_table *t, unsigned char *c, int clen, wchar_t *uni) | |
196 | { | |
197 | int charlen; | |
198 | ||
199 | charlen = t->char2uni(c, clen, uni); | |
200 | if (charlen < 0) { | |
201 | *uni = 0x003f; /* a question mark */ | |
202 | charlen = 1; | |
203 | } | |
204 | return charlen; | |
205 | } | |
206 | ||
207 | static inline int | |
208 | fat_short2lower_uni(struct nls_table *t, unsigned char *c, int clen, wchar_t *uni) | |
209 | { | |
210 | int charlen; | |
211 | wchar_t wc; | |
212 | ||
213 | charlen = t->char2uni(c, clen, &wc); | |
214 | if (charlen < 0) { | |
215 | *uni = 0x003f; /* a question mark */ | |
216 | charlen = 1; | |
217 | } else if (charlen <= 1) { | |
218 | unsigned char nc = t->charset2lower[*c]; | |
219 | ||
220 | if (!nc) | |
221 | nc = *c; | |
222 | ||
223 | if ( (charlen = t->char2uni(&nc, 1, uni)) < 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 | ||
d6886116 OH |
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 | ||
ad2c1604 PE |
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) { | |
c7a6c4ed | 287 | *unicode = __getname(); |
ad2c1604 PE |
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 | ||
deb8274a SM |
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 | ||
1da177e4 LT |
459 | /* |
460 | * Return values: negative -> error, 0 -> not found, positive -> found, | |
461 | * value is the total amount of slots, including the shortname entry. | |
462 | */ | |
463 | int fat_search_long(struct inode *inode, const unsigned char *name, | |
464 | int name_len, struct fat_slot_info *sinfo) | |
465 | { | |
466 | struct super_block *sb = inode->i_sb; | |
467 | struct msdos_sb_info *sbi = MSDOS_SB(sb); | |
468 | struct buffer_head *bh = NULL; | |
469 | struct msdos_dir_entry *de; | |
f22032ba | 470 | unsigned char nr_slots; |
1da177e4 | 471 | wchar_t *unicode = NULL; |
98a15160 | 472 | unsigned char bufname[FAT_MAX_SHORT_SIZE]; |
1da177e4 | 473 | loff_t cpos = 0; |
deb8274a | 474 | int err, len; |
1da177e4 LT |
475 | |
476 | err = -ENOENT; | |
d6886116 | 477 | while (1) { |
1da177e4 | 478 | if (fat_get_entry(inode, &cpos, &bh, &de) == -1) |
d6886116 | 479 | goto end_of_dir; |
1da177e4 LT |
480 | parse_record: |
481 | nr_slots = 0; | |
482 | if (de->name[0] == DELETED_FLAG) | |
483 | continue; | |
484 | if (de->attr != ATTR_EXT && (de->attr & ATTR_VOLUME)) | |
485 | continue; | |
486 | if (de->attr != ATTR_EXT && IS_FREE(de->name)) | |
487 | continue; | |
488 | if (de->attr == ATTR_EXT) { | |
ad2c1604 PE |
489 | int status = fat_parse_long(inode, &cpos, &bh, &de, |
490 | &unicode, &nr_slots); | |
52e9d9f4 DJ |
491 | if (status < 0) { |
492 | err = status; | |
493 | goto end_of_dir; | |
494 | } else if (status == PARSE_INVALID) | |
1da177e4 | 495 | continue; |
ad2c1604 PE |
496 | else if (status == PARSE_NOT_LONGNAME) |
497 | goto parse_record; | |
498 | else if (status == PARSE_EOF) | |
d6886116 | 499 | goto end_of_dir; |
1da177e4 LT |
500 | } |
501 | ||
deb8274a SM |
502 | /* Never prepend '.' to hidden files here. |
503 | * That is done only for msdos mounts (and only when | |
504 | * 'dotsOK=yes'); if we are executing here, it is in the | |
505 | * context of a vfat mount. | |
506 | */ | |
507 | len = fat_parse_short(sb, de, bufname, 0); | |
508 | if (len == 0) | |
1da177e4 LT |
509 | continue; |
510 | ||
d6886116 | 511 | /* Compare shortname */ |
d6886116 OH |
512 | if (fat_name_match(sbi, name, name_len, bufname, len)) |
513 | goto found; | |
1da177e4 LT |
514 | |
515 | if (nr_slots) { | |
98a15160 OH |
516 | void *longname = unicode + FAT_MAX_UNI_CHARS; |
517 | int size = PATH_MAX - FAT_MAX_UNI_SIZE; | |
518 | ||
d6886116 | 519 | /* Compare longname */ |
869f58c0 | 520 | len = fat_uni_to_x8(sb, unicode, longname, size); |
98a15160 | 521 | if (fat_name_match(sbi, name, name_len, longname, len)) |
d6886116 | 522 | goto found; |
1da177e4 LT |
523 | } |
524 | } | |
525 | ||
d6886116 | 526 | found: |
1da177e4 LT |
527 | nr_slots++; /* include the de */ |
528 | sinfo->slot_off = cpos - nr_slots * sizeof(*de); | |
529 | sinfo->nr_slots = nr_slots; | |
530 | sinfo->de = de; | |
531 | sinfo->bh = bh; | |
532 | sinfo->i_pos = fat_make_i_pos(sb, sinfo->bh, sinfo->de); | |
533 | err = 0; | |
d6886116 | 534 | end_of_dir: |
1da177e4 | 535 | if (unicode) |
c7a6c4ed | 536 | __putname(unicode); |
1da177e4 LT |
537 | |
538 | return err; | |
539 | } | |
540 | ||
7c709d00 | 541 | EXPORT_SYMBOL_GPL(fat_search_long); |
1da177e4 LT |
542 | |
543 | struct fat_ioctl_filldir_callback { | |
c483bab0 | 544 | void __user *dirent; |
1da177e4 LT |
545 | int result; |
546 | /* for dir ioctl */ | |
547 | const char *longname; | |
548 | int long_len; | |
549 | const char *shortname; | |
550 | int short_len; | |
551 | }; | |
552 | ||
ad2c1604 PE |
553 | static int __fat_readdir(struct inode *inode, struct file *filp, void *dirent, |
554 | filldir_t filldir, int short_only, int both) | |
1da177e4 LT |
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; | |
d6886116 | 560 | unsigned char nr_slots; |
1da177e4 | 561 | wchar_t *unicode = NULL; |
deb8274a | 562 | unsigned char bufname[FAT_MAX_SHORT_SIZE]; |
1da177e4 | 563 | int isvfat = sbi->options.isvfat; |
dcd8c53f | 564 | const char *fill_name = NULL; |
1da177e4 | 565 | unsigned long inum; |
d6886116 | 566 | unsigned long lpos, dummy, *furrfu = &lpos; |
1da177e4 | 567 | loff_t cpos; |
deb8274a | 568 | int short_len = 0, fill_len = 0; |
1da177e4 LT |
569 | int ret = 0; |
570 | ||
8f593427 | 571 | lock_super(sb); |
1da177e4 LT |
572 | |
573 | cpos = filp->f_pos; | |
574 | /* Fake . and .. for the root directory. */ | |
575 | if (inode->i_ino == MSDOS_ROOT_INO) { | |
576 | while (cpos < 2) { | |
577 | if (filldir(dirent, "..", cpos+1, cpos, MSDOS_ROOT_INO, DT_DIR) < 0) | |
578 | goto out; | |
579 | cpos++; | |
580 | filp->f_pos++; | |
581 | } | |
582 | if (cpos == 2) { | |
583 | dummy = 2; | |
584 | furrfu = &dummy; | |
585 | cpos = 0; | |
586 | } | |
587 | } | |
d6886116 | 588 | if (cpos & (sizeof(struct msdos_dir_entry) - 1)) { |
1da177e4 LT |
589 | ret = -ENOENT; |
590 | goto out; | |
591 | } | |
592 | ||
593 | bh = NULL; | |
d6886116 | 594 | get_new: |
1da177e4 | 595 | if (fat_get_entry(inode, &cpos, &bh, &de) == -1) |
d6886116 | 596 | goto end_of_dir; |
ad2c1604 | 597 | parse_record: |
d6886116 | 598 | nr_slots = 0; |
dcd8c53f OH |
599 | /* |
600 | * Check for long filename entry, but if short_only, we don't | |
601 | * need to parse long filename. | |
602 | */ | |
603 | if (isvfat && !short_only) { | |
1da177e4 | 604 | if (de->name[0] == DELETED_FLAG) |
d6886116 | 605 | goto record_end; |
1da177e4 | 606 | if (de->attr != ATTR_EXT && (de->attr & ATTR_VOLUME)) |
d6886116 | 607 | goto record_end; |
1da177e4 | 608 | if (de->attr != ATTR_EXT && IS_FREE(de->name)) |
d6886116 | 609 | goto record_end; |
1da177e4 LT |
610 | } else { |
611 | if ((de->attr & ATTR_VOLUME) || IS_FREE(de->name)) | |
d6886116 | 612 | goto record_end; |
1da177e4 LT |
613 | } |
614 | ||
615 | if (isvfat && de->attr == ATTR_EXT) { | |
ad2c1604 | 616 | int status = fat_parse_long(inode, &cpos, &bh, &de, |
d6886116 | 617 | &unicode, &nr_slots); |
ad2c1604 PE |
618 | if (status < 0) { |
619 | filp->f_pos = cpos; | |
620 | ret = status; | |
621 | goto out; | |
622 | } else if (status == PARSE_INVALID) | |
d6886116 | 623 | goto record_end; |
ad2c1604 PE |
624 | else if (status == PARSE_NOT_LONGNAME) |
625 | goto parse_record; | |
626 | else if (status == PARSE_EOF) | |
d6886116 | 627 | goto end_of_dir; |
dcd8c53f OH |
628 | |
629 | if (nr_slots) { | |
630 | void *longname = unicode + FAT_MAX_UNI_CHARS; | |
631 | int size = PATH_MAX - FAT_MAX_UNI_SIZE; | |
869f58c0 | 632 | int len = fat_uni_to_x8(sb, unicode, longname, size); |
dcd8c53f OH |
633 | |
634 | fill_name = longname; | |
635 | fill_len = len; | |
636 | /* !both && !short_only, so we don't need shortname. */ | |
637 | if (!both) | |
638 | goto start_filldir; | |
639 | } | |
1da177e4 LT |
640 | } |
641 | ||
deb8274a SM |
642 | short_len = fat_parse_short(sb, de, bufname, sbi->options.dotsOK); |
643 | if (short_len == 0) | |
d6886116 | 644 | goto record_end; |
1da177e4 | 645 | |
dcd8c53f OH |
646 | if (nr_slots) { |
647 | /* hack for fat_ioctl_filldir() */ | |
648 | struct fat_ioctl_filldir_callback *p = dirent; | |
649 | ||
650 | p->longname = fill_name; | |
651 | p->long_len = fill_len; | |
652 | p->shortname = bufname; | |
deb8274a | 653 | p->short_len = short_len; |
dcd8c53f OH |
654 | fill_name = NULL; |
655 | fill_len = 0; | |
656 | } else { | |
657 | fill_name = bufname; | |
deb8274a | 658 | fill_len = short_len; |
dcd8c53f OH |
659 | } |
660 | ||
661 | start_filldir: | |
d6886116 | 662 | lpos = cpos - (nr_slots + 1) * sizeof(struct msdos_dir_entry); |
1da177e4 LT |
663 | if (!memcmp(de->name, MSDOS_DOT, MSDOS_NAME)) |
664 | inum = inode->i_ino; | |
665 | else if (!memcmp(de->name, MSDOS_DOTDOT, MSDOS_NAME)) { | |
dba32306 | 666 | inum = parent_ino(filp->f_path.dentry); |
1da177e4 LT |
667 | } else { |
668 | loff_t i_pos = fat_make_i_pos(sb, bh, de); | |
669 | struct inode *tmp = fat_iget(sb, i_pos); | |
670 | if (tmp) { | |
671 | inum = tmp->i_ino; | |
672 | iput(tmp); | |
673 | } else | |
674 | inum = iunique(sb, MSDOS_ROOT_INO); | |
675 | } | |
676 | ||
1da177e4 LT |
677 | if (filldir(dirent, fill_name, fill_len, *furrfu, inum, |
678 | (de->attr & ATTR_DIR) ? DT_DIR : DT_REG) < 0) | |
d6886116 | 679 | goto fill_failed; |
1da177e4 | 680 | |
d6886116 | 681 | record_end: |
1da177e4 LT |
682 | furrfu = &lpos; |
683 | filp->f_pos = cpos; | |
d6886116 OH |
684 | goto get_new; |
685 | end_of_dir: | |
1da177e4 | 686 | filp->f_pos = cpos; |
d6886116 | 687 | fill_failed: |
f3ef6f63 | 688 | brelse(bh); |
1da177e4 | 689 | if (unicode) |
c7a6c4ed | 690 | __putname(unicode); |
1da177e4 | 691 | out: |
8f593427 | 692 | unlock_super(sb); |
1da177e4 LT |
693 | return ret; |
694 | } | |
695 | ||
696 | static int fat_readdir(struct file *filp, void *dirent, filldir_t filldir) | |
697 | { | |
dba32306 | 698 | struct inode *inode = filp->f_path.dentry->d_inode; |
ad2c1604 | 699 | return __fat_readdir(inode, filp, dirent, filldir, 0, 0); |
1da177e4 LT |
700 | } |
701 | ||
c483bab0 OH |
702 | #define FAT_IOCTL_FILLDIR_FUNC(func, dirent_type) \ |
703 | static int func(void *__buf, const char *name, int name_len, \ | |
704 | loff_t offset, u64 ino, unsigned int d_type) \ | |
705 | { \ | |
706 | struct fat_ioctl_filldir_callback *buf = __buf; \ | |
707 | struct dirent_type __user *d1 = buf->dirent; \ | |
708 | struct dirent_type __user *d2 = d1 + 1; \ | |
709 | \ | |
710 | if (buf->result) \ | |
711 | return -EINVAL; \ | |
712 | buf->result++; \ | |
713 | \ | |
714 | if (name != NULL) { \ | |
715 | /* dirent has only short name */ \ | |
716 | if (name_len >= sizeof(d1->d_name)) \ | |
717 | name_len = sizeof(d1->d_name) - 1; \ | |
718 | \ | |
719 | if (put_user(0, d2->d_name) || \ | |
720 | put_user(0, &d2->d_reclen) || \ | |
721 | copy_to_user(d1->d_name, name, name_len) || \ | |
722 | put_user(0, d1->d_name + name_len) || \ | |
723 | put_user(name_len, &d1->d_reclen)) \ | |
724 | goto efault; \ | |
725 | } else { \ | |
726 | /* dirent has short and long name */ \ | |
727 | const char *longname = buf->longname; \ | |
728 | int long_len = buf->long_len; \ | |
729 | const char *shortname = buf->shortname; \ | |
730 | int short_len = buf->short_len; \ | |
731 | \ | |
732 | if (long_len >= sizeof(d1->d_name)) \ | |
733 | long_len = sizeof(d1->d_name) - 1; \ | |
734 | if (short_len >= sizeof(d1->d_name)) \ | |
735 | short_len = sizeof(d1->d_name) - 1; \ | |
736 | \ | |
737 | if (copy_to_user(d2->d_name, longname, long_len) || \ | |
738 | put_user(0, d2->d_name + long_len) || \ | |
739 | put_user(long_len, &d2->d_reclen) || \ | |
740 | put_user(ino, &d2->d_ino) || \ | |
741 | put_user(offset, &d2->d_off) || \ | |
742 | copy_to_user(d1->d_name, shortname, short_len) || \ | |
743 | put_user(0, d1->d_name + short_len) || \ | |
744 | put_user(short_len, &d1->d_reclen)) \ | |
745 | goto efault; \ | |
746 | } \ | |
747 | return 0; \ | |
748 | efault: \ | |
749 | buf->result = -EFAULT; \ | |
750 | return -EFAULT; \ | |
751 | } | |
752 | ||
531f710f | 753 | FAT_IOCTL_FILLDIR_FUNC(fat_ioctl_filldir, __fat_dirent) |
c483bab0 OH |
754 | |
755 | static int fat_ioctl_readdir(struct inode *inode, struct file *filp, | |
756 | void __user *dirent, filldir_t filldir, | |
757 | int short_only, int both) | |
1da177e4 | 758 | { |
c483bab0 OH |
759 | struct fat_ioctl_filldir_callback buf; |
760 | int ret; | |
761 | ||
762 | buf.dirent = dirent; | |
763 | buf.result = 0; | |
764 | mutex_lock(&inode->i_mutex); | |
765 | ret = -ENOENT; | |
766 | if (!IS_DEADDIR(inode)) { | |
767 | ret = __fat_readdir(inode, filp, &buf, filldir, | |
768 | short_only, both); | |
1da177e4 | 769 | } |
c483bab0 OH |
770 | mutex_unlock(&inode->i_mutex); |
771 | if (ret >= 0) | |
772 | ret = buf.result; | |
773 | return ret; | |
1da177e4 LT |
774 | } |
775 | ||
7845bc3e AB |
776 | static long fat_dir_ioctl(struct file *filp, unsigned int cmd, |
777 | unsigned long arg) | |
1da177e4 | 778 | { |
7845bc3e | 779 | struct inode *inode = filp->f_path.dentry->d_inode; |
531f710f | 780 | struct __fat_dirent __user *d1 = (struct __fat_dirent __user *)arg; |
c483bab0 | 781 | int short_only, both; |
1da177e4 LT |
782 | |
783 | switch (cmd) { | |
784 | case VFAT_IOCTL_READDIR_SHORT: | |
785 | short_only = 1; | |
786 | both = 0; | |
787 | break; | |
788 | case VFAT_IOCTL_READDIR_BOTH: | |
789 | short_only = 0; | |
790 | both = 1; | |
791 | break; | |
792 | default: | |
7845bc3e | 793 | return fat_generic_ioctl(filp, cmd, arg); |
1da177e4 LT |
794 | } |
795 | ||
531f710f | 796 | if (!access_ok(VERIFY_WRITE, d1, sizeof(struct __fat_dirent[2]))) |
1da177e4 LT |
797 | return -EFAULT; |
798 | /* | |
799 | * Yes, we don't need this put_user() absolutely. However old | |
800 | * code didn't return the right value. So, app use this value, | |
801 | * in order to check whether it is EOF. | |
802 | */ | |
803 | if (put_user(0, &d1->d_reclen)) | |
804 | return -EFAULT; | |
805 | ||
c483bab0 OH |
806 | return fat_ioctl_readdir(inode, filp, d1, fat_ioctl_filldir, |
807 | short_only, both); | |
1da177e4 LT |
808 | } |
809 | ||
188f83df DH |
810 | #ifdef CONFIG_COMPAT |
811 | #define VFAT_IOCTL_READDIR_BOTH32 _IOR('r', 1, struct compat_dirent[2]) | |
812 | #define VFAT_IOCTL_READDIR_SHORT32 _IOR('r', 2, struct compat_dirent[2]) | |
813 | ||
c483bab0 | 814 | FAT_IOCTL_FILLDIR_FUNC(fat_compat_ioctl_filldir, compat_dirent) |
188f83df | 815 | |
c483bab0 | 816 | static long fat_compat_dir_ioctl(struct file *filp, unsigned cmd, |
188f83df DH |
817 | unsigned long arg) |
818 | { | |
c483bab0 OH |
819 | struct inode *inode = filp->f_path.dentry->d_inode; |
820 | struct compat_dirent __user *d1 = compat_ptr(arg); | |
821 | int short_only, both; | |
188f83df DH |
822 | |
823 | switch (cmd) { | |
188f83df | 824 | case VFAT_IOCTL_READDIR_SHORT32: |
c483bab0 OH |
825 | short_only = 1; |
826 | both = 0; | |
827 | break; | |
828 | case VFAT_IOCTL_READDIR_BOTH32: | |
829 | short_only = 0; | |
830 | both = 1; | |
188f83df DH |
831 | break; |
832 | default: | |
7845bc3e | 833 | return fat_generic_ioctl(filp, cmd, (unsigned long)arg); |
188f83df DH |
834 | } |
835 | ||
c483bab0 OH |
836 | if (!access_ok(VERIFY_WRITE, d1, sizeof(struct compat_dirent[2]))) |
837 | return -EFAULT; | |
838 | /* | |
839 | * Yes, we don't need this put_user() absolutely. However old | |
840 | * code didn't return the right value. So, app use this value, | |
841 | * in order to check whether it is EOF. | |
842 | */ | |
843 | if (put_user(0, &d1->d_reclen)) | |
844 | return -EFAULT; | |
845 | ||
846 | return fat_ioctl_readdir(inode, filp, d1, fat_compat_ioctl_filldir, | |
847 | short_only, both); | |
188f83df DH |
848 | } |
849 | #endif /* CONFIG_COMPAT */ | |
850 | ||
4b6f5d20 | 851 | const struct file_operations fat_dir_operations = { |
53472bc8 | 852 | .llseek = generic_file_llseek, |
1da177e4 LT |
853 | .read = generic_read_dir, |
854 | .readdir = fat_readdir, | |
7845bc3e | 855 | .unlocked_ioctl = fat_dir_ioctl, |
188f83df DH |
856 | #ifdef CONFIG_COMPAT |
857 | .compat_ioctl = fat_compat_dir_ioctl, | |
858 | #endif | |
b522412a | 859 | .fsync = fat_file_fsync, |
1da177e4 LT |
860 | }; |
861 | ||
862 | static int fat_get_short_entry(struct inode *dir, loff_t *pos, | |
863 | struct buffer_head **bh, | |
864 | struct msdos_dir_entry **de) | |
865 | { | |
866 | while (fat_get_entry(dir, pos, bh, de) >= 0) { | |
867 | /* free entry or long name entry or volume label */ | |
868 | if (!IS_FREE((*de)->name) && !((*de)->attr & ATTR_VOLUME)) | |
869 | return 0; | |
870 | } | |
871 | return -ENOENT; | |
872 | } | |
873 | ||
874 | /* | |
875 | * The ".." entry can not provide the "struct fat_slot_info" informations | |
876 | * for inode. So, this function provide the some informations only. | |
877 | */ | |
878 | int fat_get_dotdot_entry(struct inode *dir, struct buffer_head **bh, | |
879 | struct msdos_dir_entry **de, loff_t *i_pos) | |
880 | { | |
881 | loff_t offset; | |
882 | ||
883 | offset = 0; | |
884 | *bh = NULL; | |
885 | while (fat_get_short_entry(dir, &offset, bh, de) >= 0) { | |
886 | if (!strncmp((*de)->name, MSDOS_DOTDOT, MSDOS_NAME)) { | |
887 | *i_pos = fat_make_i_pos(dir->i_sb, *bh, *de); | |
888 | return 0; | |
889 | } | |
890 | } | |
891 | return -ENOENT; | |
892 | } | |
893 | ||
7c709d00 | 894 | EXPORT_SYMBOL_GPL(fat_get_dotdot_entry); |
1da177e4 LT |
895 | |
896 | /* See if directory is empty */ | |
897 | int fat_dir_empty(struct inode *dir) | |
898 | { | |
899 | struct buffer_head *bh; | |
900 | struct msdos_dir_entry *de; | |
901 | loff_t cpos; | |
902 | int result = 0; | |
903 | ||
904 | bh = NULL; | |
905 | cpos = 0; | |
906 | while (fat_get_short_entry(dir, &cpos, &bh, &de) >= 0) { | |
907 | if (strncmp(de->name, MSDOS_DOT , MSDOS_NAME) && | |
908 | strncmp(de->name, MSDOS_DOTDOT, MSDOS_NAME)) { | |
909 | result = -ENOTEMPTY; | |
910 | break; | |
911 | } | |
912 | } | |
913 | brelse(bh); | |
914 | return result; | |
915 | } | |
916 | ||
7c709d00 | 917 | EXPORT_SYMBOL_GPL(fat_dir_empty); |
1da177e4 LT |
918 | |
919 | /* | |
920 | * fat_subdirs counts the number of sub-directories of dir. It can be run | |
921 | * on directories being created. | |
922 | */ | |
923 | int fat_subdirs(struct inode *dir) | |
924 | { | |
925 | struct buffer_head *bh; | |
926 | struct msdos_dir_entry *de; | |
927 | loff_t cpos; | |
928 | int count = 0; | |
929 | ||
930 | bh = NULL; | |
931 | cpos = 0; | |
932 | while (fat_get_short_entry(dir, &cpos, &bh, &de) >= 0) { | |
933 | if (de->attr & ATTR_DIR) | |
934 | count++; | |
935 | } | |
936 | brelse(bh); | |
937 | return count; | |
938 | } | |
939 | ||
940 | /* | |
941 | * Scans a directory for a given file (name points to its formatted name). | |
942 | * Returns an error code or zero. | |
943 | */ | |
944 | int fat_scan(struct inode *dir, const unsigned char *name, | |
945 | struct fat_slot_info *sinfo) | |
946 | { | |
947 | struct super_block *sb = dir->i_sb; | |
948 | ||
949 | sinfo->slot_off = 0; | |
950 | sinfo->bh = NULL; | |
951 | while (fat_get_short_entry(dir, &sinfo->slot_off, &sinfo->bh, | |
952 | &sinfo->de) >= 0) { | |
953 | if (!strncmp(sinfo->de->name, name, MSDOS_NAME)) { | |
954 | sinfo->slot_off -= sizeof(*sinfo->de); | |
955 | sinfo->nr_slots = 1; | |
956 | sinfo->i_pos = fat_make_i_pos(sb, sinfo->bh, sinfo->de); | |
957 | return 0; | |
958 | } | |
959 | } | |
960 | return -ENOENT; | |
961 | } | |
962 | ||
7c709d00 | 963 | EXPORT_SYMBOL_GPL(fat_scan); |
1da177e4 LT |
964 | |
965 | static int __fat_remove_entries(struct inode *dir, loff_t pos, int nr_slots) | |
966 | { | |
967 | struct super_block *sb = dir->i_sb; | |
968 | struct buffer_head *bh; | |
969 | struct msdos_dir_entry *de, *endp; | |
970 | int err = 0, orig_slots; | |
971 | ||
972 | while (nr_slots) { | |
973 | bh = NULL; | |
974 | if (fat_get_entry(dir, &pos, &bh, &de) < 0) { | |
975 | err = -EIO; | |
976 | break; | |
977 | } | |
978 | ||
979 | orig_slots = nr_slots; | |
980 | endp = (struct msdos_dir_entry *)(bh->b_data + sb->s_blocksize); | |
981 | while (nr_slots && de < endp) { | |
982 | de->name[0] = DELETED_FLAG; | |
983 | de++; | |
984 | nr_slots--; | |
985 | } | |
b522412a | 986 | mark_buffer_dirty_inode(bh, dir); |
1da177e4 LT |
987 | if (IS_DIRSYNC(dir)) |
988 | err = sync_dirty_buffer(bh); | |
989 | brelse(bh); | |
990 | if (err) | |
991 | break; | |
992 | ||
993 | /* pos is *next* de's position, so this does `- sizeof(de)' */ | |
994 | pos += ((orig_slots - nr_slots) * sizeof(*de)) - sizeof(*de); | |
995 | } | |
996 | ||
997 | return err; | |
998 | } | |
999 | ||
1000 | int fat_remove_entries(struct inode *dir, struct fat_slot_info *sinfo) | |
1001 | { | |
869f58c0 | 1002 | struct super_block *sb = dir->i_sb; |
1da177e4 LT |
1003 | struct msdos_dir_entry *de; |
1004 | struct buffer_head *bh; | |
1005 | int err = 0, nr_slots; | |
1006 | ||
1007 | /* | |
1008 | * First stage: Remove the shortname. By this, the directory | |
1009 | * entry is removed. | |
1010 | */ | |
1011 | nr_slots = sinfo->nr_slots; | |
1012 | de = sinfo->de; | |
1013 | sinfo->de = NULL; | |
1014 | bh = sinfo->bh; | |
1015 | sinfo->bh = NULL; | |
1016 | while (nr_slots && de >= (struct msdos_dir_entry *)bh->b_data) { | |
1017 | de->name[0] = DELETED_FLAG; | |
1018 | de--; | |
1019 | nr_slots--; | |
1020 | } | |
b522412a | 1021 | mark_buffer_dirty_inode(bh, dir); |
1da177e4 LT |
1022 | if (IS_DIRSYNC(dir)) |
1023 | err = sync_dirty_buffer(bh); | |
1024 | brelse(bh); | |
1025 | if (err) | |
1026 | return err; | |
1027 | dir->i_version++; | |
1028 | ||
1029 | if (nr_slots) { | |
1030 | /* | |
1031 | * Second stage: remove the remaining longname slots. | |
1032 | * (This directory entry is already removed, and so return | |
1033 | * the success) | |
1034 | */ | |
1035 | err = __fat_remove_entries(dir, sinfo->slot_off, nr_slots); | |
1036 | if (err) { | |
869f58c0 AF |
1037 | fat_msg(sb, KERN_WARNING, |
1038 | "Couldn't remove the long name slots"); | |
1da177e4 LT |
1039 | } |
1040 | } | |
1041 | ||
1042 | dir->i_mtime = dir->i_atime = CURRENT_TIME_SEC; | |
1043 | if (IS_DIRSYNC(dir)) | |
1044 | (void)fat_sync_inode(dir); | |
1045 | else | |
1046 | mark_inode_dirty(dir); | |
1047 | ||
1048 | return 0; | |
1049 | } | |
1050 | ||
7c709d00 | 1051 | EXPORT_SYMBOL_GPL(fat_remove_entries); |
1da177e4 LT |
1052 | |
1053 | static int fat_zeroed_cluster(struct inode *dir, sector_t blknr, int nr_used, | |
1054 | struct buffer_head **bhs, int nr_bhs) | |
1055 | { | |
1056 | struct super_block *sb = dir->i_sb; | |
1057 | sector_t last_blknr = blknr + MSDOS_SB(sb)->sec_per_clus; | |
1058 | int err, i, n; | |
1059 | ||
1060 | /* Zeroing the unused blocks on this cluster */ | |
1061 | blknr += nr_used; | |
1062 | n = nr_used; | |
1063 | while (blknr < last_blknr) { | |
1064 | bhs[n] = sb_getblk(sb, blknr); | |
1065 | if (!bhs[n]) { | |
1066 | err = -ENOMEM; | |
1067 | goto error; | |
1068 | } | |
1069 | memset(bhs[n]->b_data, 0, sb->s_blocksize); | |
1070 | set_buffer_uptodate(bhs[n]); | |
b522412a | 1071 | mark_buffer_dirty_inode(bhs[n], dir); |
1da177e4 LT |
1072 | |
1073 | n++; | |
1074 | blknr++; | |
1075 | if (n == nr_bhs) { | |
1076 | if (IS_DIRSYNC(dir)) { | |
1077 | err = fat_sync_bhs(bhs, n); | |
1078 | if (err) | |
1079 | goto error; | |
1080 | } | |
1081 | for (i = 0; i < n; i++) | |
1082 | brelse(bhs[i]); | |
1083 | n = 0; | |
1084 | } | |
1085 | } | |
1086 | if (IS_DIRSYNC(dir)) { | |
1087 | err = fat_sync_bhs(bhs, n); | |
1088 | if (err) | |
1089 | goto error; | |
1090 | } | |
1091 | for (i = 0; i < n; i++) | |
1092 | brelse(bhs[i]); | |
1093 | ||
1094 | return 0; | |
1095 | ||
1096 | error: | |
1097 | for (i = 0; i < n; i++) | |
1098 | bforget(bhs[i]); | |
1099 | return err; | |
1100 | } | |
1101 | ||
1102 | int fat_alloc_new_dir(struct inode *dir, struct timespec *ts) | |
1103 | { | |
1104 | struct super_block *sb = dir->i_sb; | |
1105 | struct msdos_sb_info *sbi = MSDOS_SB(sb); | |
1106 | struct buffer_head *bhs[MAX_BUF_PER_PAGE]; | |
1107 | struct msdos_dir_entry *de; | |
1108 | sector_t blknr; | |
1109 | __le16 date, time; | |
7decd1cb | 1110 | u8 time_cs; |
1da177e4 LT |
1111 | int err, cluster; |
1112 | ||
1113 | err = fat_alloc_clusters(dir, &cluster, 1); | |
1114 | if (err) | |
1115 | goto error; | |
1116 | ||
1117 | blknr = fat_clus_to_blknr(sbi, cluster); | |
1118 | bhs[0] = sb_getblk(sb, blknr); | |
1119 | if (!bhs[0]) { | |
1120 | err = -ENOMEM; | |
1121 | goto error_free; | |
1122 | } | |
1123 | ||
7decd1cb | 1124 | fat_time_unix2fat(sbi, ts, &time, &date, &time_cs); |
1da177e4 LT |
1125 | |
1126 | de = (struct msdos_dir_entry *)bhs[0]->b_data; | |
1127 | /* filling the new directory slots ("." and ".." entries) */ | |
1128 | memcpy(de[0].name, MSDOS_DOT, MSDOS_NAME); | |
1129 | memcpy(de[1].name, MSDOS_DOTDOT, MSDOS_NAME); | |
1130 | de->attr = de[1].attr = ATTR_DIR; | |
1131 | de[0].lcase = de[1].lcase = 0; | |
1132 | de[0].time = de[1].time = time; | |
1133 | de[0].date = de[1].date = date; | |
1da177e4 LT |
1134 | if (sbi->options.isvfat) { |
1135 | /* extra timestamps */ | |
1136 | de[0].ctime = de[1].ctime = time; | |
7decd1cb | 1137 | de[0].ctime_cs = de[1].ctime_cs = time_cs; |
1da177e4 LT |
1138 | de[0].adate = de[0].cdate = de[1].adate = de[1].cdate = date; |
1139 | } else { | |
1140 | de[0].ctime = de[1].ctime = 0; | |
7decd1cb | 1141 | de[0].ctime_cs = de[1].ctime_cs = 0; |
1da177e4 LT |
1142 | de[0].adate = de[0].cdate = de[1].adate = de[1].cdate = 0; |
1143 | } | |
1144 | de[0].start = cpu_to_le16(cluster); | |
1145 | de[0].starthi = cpu_to_le16(cluster >> 16); | |
1146 | de[1].start = cpu_to_le16(MSDOS_I(dir)->i_logstart); | |
1147 | de[1].starthi = cpu_to_le16(MSDOS_I(dir)->i_logstart >> 16); | |
1148 | de[0].size = de[1].size = 0; | |
1149 | memset(de + 2, 0, sb->s_blocksize - 2 * sizeof(*de)); | |
1150 | set_buffer_uptodate(bhs[0]); | |
b522412a | 1151 | mark_buffer_dirty_inode(bhs[0], dir); |
1da177e4 LT |
1152 | |
1153 | err = fat_zeroed_cluster(dir, blknr, 1, bhs, MAX_BUF_PER_PAGE); | |
1154 | if (err) | |
1155 | goto error_free; | |
1156 | ||
1157 | return cluster; | |
1158 | ||
1159 | error_free: | |
1160 | fat_free_clusters(dir, cluster); | |
1161 | error: | |
1162 | return err; | |
1163 | } | |
1164 | ||
7c709d00 | 1165 | EXPORT_SYMBOL_GPL(fat_alloc_new_dir); |
1da177e4 LT |
1166 | |
1167 | static int fat_add_new_entries(struct inode *dir, void *slots, int nr_slots, | |
1168 | int *nr_cluster, struct msdos_dir_entry **de, | |
1169 | struct buffer_head **bh, loff_t *i_pos) | |
1170 | { | |
1171 | struct super_block *sb = dir->i_sb; | |
1172 | struct msdos_sb_info *sbi = MSDOS_SB(sb); | |
1173 | struct buffer_head *bhs[MAX_BUF_PER_PAGE]; | |
1174 | sector_t blknr, start_blknr, last_blknr; | |
1175 | unsigned long size, copy; | |
1176 | int err, i, n, offset, cluster[2]; | |
1177 | ||
1178 | /* | |
1179 | * The minimum cluster size is 512bytes, and maximum entry | |
1180 | * size is 32*slots (672bytes). So, iff the cluster size is | |
1181 | * 512bytes, we may need two clusters. | |
1182 | */ | |
1183 | size = nr_slots * sizeof(struct msdos_dir_entry); | |
1184 | *nr_cluster = (size + (sbi->cluster_size - 1)) >> sbi->cluster_bits; | |
1185 | BUG_ON(*nr_cluster > 2); | |
1186 | ||
1187 | err = fat_alloc_clusters(dir, cluster, *nr_cluster); | |
1188 | if (err) | |
1189 | goto error; | |
1190 | ||
1191 | /* | |
1192 | * First stage: Fill the directory entry. NOTE: This cluster | |
1193 | * is not referenced from any inode yet, so updates order is | |
1194 | * not important. | |
1195 | */ | |
1196 | i = n = copy = 0; | |
1197 | do { | |
1198 | start_blknr = blknr = fat_clus_to_blknr(sbi, cluster[i]); | |
1199 | last_blknr = start_blknr + sbi->sec_per_clus; | |
1200 | while (blknr < last_blknr) { | |
1201 | bhs[n] = sb_getblk(sb, blknr); | |
1202 | if (!bhs[n]) { | |
1203 | err = -ENOMEM; | |
1204 | goto error_nomem; | |
1205 | } | |
1206 | ||
1207 | /* fill the directory entry */ | |
1208 | copy = min(size, sb->s_blocksize); | |
1209 | memcpy(bhs[n]->b_data, slots, copy); | |
1210 | slots += copy; | |
1211 | size -= copy; | |
1212 | set_buffer_uptodate(bhs[n]); | |
b522412a | 1213 | mark_buffer_dirty_inode(bhs[n], dir); |
1da177e4 LT |
1214 | if (!size) |
1215 | break; | |
1216 | n++; | |
1217 | blknr++; | |
1218 | } | |
1219 | } while (++i < *nr_cluster); | |
1220 | ||
1221 | memset(bhs[n]->b_data + copy, 0, sb->s_blocksize - copy); | |
1222 | offset = copy - sizeof(struct msdos_dir_entry); | |
1223 | get_bh(bhs[n]); | |
1224 | *bh = bhs[n]; | |
1225 | *de = (struct msdos_dir_entry *)((*bh)->b_data + offset); | |
1226 | *i_pos = fat_make_i_pos(sb, *bh, *de); | |
1227 | ||
1228 | /* Second stage: clear the rest of cluster, and write outs */ | |
1229 | err = fat_zeroed_cluster(dir, start_blknr, ++n, bhs, MAX_BUF_PER_PAGE); | |
1230 | if (err) | |
1231 | goto error_free; | |
1232 | ||
1233 | return cluster[0]; | |
1234 | ||
1235 | error_free: | |
1236 | brelse(*bh); | |
1237 | *bh = NULL; | |
1238 | n = 0; | |
1239 | error_nomem: | |
1240 | for (i = 0; i < n; i++) | |
1241 | bforget(bhs[i]); | |
1242 | fat_free_clusters(dir, cluster[0]); | |
1243 | error: | |
1244 | return err; | |
1245 | } | |
1246 | ||
1247 | int fat_add_entries(struct inode *dir, void *slots, int nr_slots, | |
1248 | struct fat_slot_info *sinfo) | |
1249 | { | |
1250 | struct super_block *sb = dir->i_sb; | |
1251 | struct msdos_sb_info *sbi = MSDOS_SB(sb); | |
1252 | struct buffer_head *bh, *prev, *bhs[3]; /* 32*slots (672bytes) */ | |
8c320c07 | 1253 | struct msdos_dir_entry *uninitialized_var(de); |
1da177e4 LT |
1254 | int err, free_slots, i, nr_bhs; |
1255 | loff_t pos, i_pos; | |
1256 | ||
1257 | sinfo->nr_slots = nr_slots; | |
1258 | ||
1259 | /* First stage: search free direcotry entries */ | |
1260 | free_slots = nr_bhs = 0; | |
1261 | bh = prev = NULL; | |
1262 | pos = 0; | |
1263 | err = -ENOSPC; | |
1264 | while (fat_get_entry(dir, &pos, &bh, &de) > -1) { | |
1265 | /* check the maximum size of directory */ | |
1266 | if (pos >= FAT_MAX_DIR_SIZE) | |
1267 | goto error; | |
1268 | ||
1269 | if (IS_FREE(de->name)) { | |
1270 | if (prev != bh) { | |
1271 | get_bh(bh); | |
1272 | bhs[nr_bhs] = prev = bh; | |
1273 | nr_bhs++; | |
1274 | } | |
1275 | free_slots++; | |
1276 | if (free_slots == nr_slots) | |
1277 | goto found; | |
1278 | } else { | |
1279 | for (i = 0; i < nr_bhs; i++) | |
1280 | brelse(bhs[i]); | |
1281 | prev = NULL; | |
1282 | free_slots = nr_bhs = 0; | |
1283 | } | |
1284 | } | |
1285 | if (dir->i_ino == MSDOS_ROOT_INO) { | |
1286 | if (sbi->fat_bits != 32) | |
1287 | goto error; | |
1288 | } else if (MSDOS_I(dir)->i_start == 0) { | |
869f58c0 | 1289 | fat_msg(sb, KERN_ERR, "Corrupted directory (i_pos %lld)", |
1da177e4 LT |
1290 | MSDOS_I(dir)->i_pos); |
1291 | err = -EIO; | |
1292 | goto error; | |
1293 | } | |
1294 | ||
1295 | found: | |
1296 | err = 0; | |
1297 | pos -= free_slots * sizeof(*de); | |
1298 | nr_slots -= free_slots; | |
1299 | if (free_slots) { | |
1300 | /* | |
1301 | * Second stage: filling the free entries with new entries. | |
1302 | * NOTE: If this slots has shortname, first, we write | |
1303 | * the long name slots, then write the short name. | |
1304 | */ | |
1305 | int size = free_slots * sizeof(*de); | |
1306 | int offset = pos & (sb->s_blocksize - 1); | |
1307 | int long_bhs = nr_bhs - (nr_slots == 0); | |
1308 | ||
1309 | /* Fill the long name slots. */ | |
1310 | for (i = 0; i < long_bhs; i++) { | |
1311 | int copy = min_t(int, sb->s_blocksize - offset, size); | |
1312 | memcpy(bhs[i]->b_data + offset, slots, copy); | |
b522412a | 1313 | mark_buffer_dirty_inode(bhs[i], dir); |
1da177e4 LT |
1314 | offset = 0; |
1315 | slots += copy; | |
1316 | size -= copy; | |
1317 | } | |
1318 | if (long_bhs && IS_DIRSYNC(dir)) | |
1319 | err = fat_sync_bhs(bhs, long_bhs); | |
1320 | if (!err && i < nr_bhs) { | |
1321 | /* Fill the short name slot. */ | |
1322 | int copy = min_t(int, sb->s_blocksize - offset, size); | |
1323 | memcpy(bhs[i]->b_data + offset, slots, copy); | |
b522412a | 1324 | mark_buffer_dirty_inode(bhs[i], dir); |
1da177e4 LT |
1325 | if (IS_DIRSYNC(dir)) |
1326 | err = sync_dirty_buffer(bhs[i]); | |
1327 | } | |
1328 | for (i = 0; i < nr_bhs; i++) | |
1329 | brelse(bhs[i]); | |
1330 | if (err) | |
1331 | goto error_remove; | |
1332 | } | |
1333 | ||
1334 | if (nr_slots) { | |
1335 | int cluster, nr_cluster; | |
1336 | ||
1337 | /* | |
1338 | * Third stage: allocate the cluster for new entries. | |
1339 | * And initialize the cluster with new entries, then | |
1340 | * add the cluster to dir. | |
1341 | */ | |
1342 | cluster = fat_add_new_entries(dir, slots, nr_slots, &nr_cluster, | |
1343 | &de, &bh, &i_pos); | |
1344 | if (cluster < 0) { | |
1345 | err = cluster; | |
1346 | goto error_remove; | |
1347 | } | |
1348 | err = fat_chain_add(dir, cluster, nr_cluster); | |
1349 | if (err) { | |
1350 | fat_free_clusters(dir, cluster); | |
1351 | goto error_remove; | |
1352 | } | |
1353 | if (dir->i_size & (sbi->cluster_size - 1)) { | |
85c78591 | 1354 | fat_fs_error(sb, "Odd directory size"); |
1da177e4 LT |
1355 | dir->i_size = (dir->i_size + sbi->cluster_size - 1) |
1356 | & ~((loff_t)sbi->cluster_size - 1); | |
1357 | } | |
1358 | dir->i_size += nr_cluster << sbi->cluster_bits; | |
1359 | MSDOS_I(dir)->mmu_private += nr_cluster << sbi->cluster_bits; | |
1360 | } | |
1361 | sinfo->slot_off = pos; | |
1362 | sinfo->de = de; | |
1363 | sinfo->bh = bh; | |
1364 | sinfo->i_pos = fat_make_i_pos(sb, sinfo->bh, sinfo->de); | |
1365 | ||
1366 | return 0; | |
1367 | ||
1368 | error: | |
1369 | brelse(bh); | |
1370 | for (i = 0; i < nr_bhs; i++) | |
1371 | brelse(bhs[i]); | |
1372 | return err; | |
1373 | ||
1374 | error_remove: | |
1375 | brelse(bh); | |
1376 | if (free_slots) | |
1377 | __fat_remove_entries(dir, pos, free_slots); | |
1378 | return err; | |
1379 | } | |
1380 | ||
7c709d00 | 1381 | EXPORT_SYMBOL_GPL(fat_add_entries); |