Commit | Line | Data |
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457c8996 | 1 | // SPDX-License-Identifier: GPL-2.0-only |
1da177e4 LT |
2 | /* |
3 | * linux/fs/fat/dir.c | |
4 | * | |
5 | * directory handling functions for fat-based filesystems | |
6 | * | |
7 | * Written 1992,1993 by Werner Almesberger | |
8 | * | |
9 | * Hidden files 1995 by Albert Cahalan <albert@ccs.neu.edu> <adc@coe.neu.edu> | |
10 | * | |
11 | * VFAT extensions by Gordon Chaffee <chaffee@plateau.cs.berkeley.edu> | |
12 | * Merged with msdos fs by Henrik Storner <storner@osiris.ping.dk> | |
13 | * Rewritten for constant inumbers. Plugged buffer overrun in readdir(). AV | |
14 | * Short name translation 1999, 2001 by Wolfram Pienkoss <wp@bszh.de> | |
15 | */ | |
16 | ||
1da177e4 | 17 | #include <linux/slab.h> |
188f83df | 18 | #include <linux/compat.h> |
f08b4988 | 19 | #include <linux/uaccess.h> |
2489dbab | 20 | #include <linux/iversion.h> |
9e975dae | 21 | #include "fat.h" |
1da177e4 | 22 | |
74675a58 AS |
23 | /* |
24 | * Maximum buffer size of short name. | |
25 | * [(MSDOS_NAME + '.') * max one char + nul] | |
26 | * For msdos style, ['.' (hidden) + MSDOS_NAME + '.' + nul] | |
27 | */ | |
28 | #define FAT_MAX_SHORT_SIZE ((MSDOS_NAME + 1) * NLS_MAX_CHARSET_SIZE + 1) | |
29 | /* | |
30 | * Maximum buffer size of unicode chars from slots. | |
31 | * [(max longname slots * 13 (size in a slot) + nul) * sizeof(wchar_t)] | |
32 | */ | |
33 | #define FAT_MAX_UNI_CHARS ((MSDOS_SLOTS - 1) * 13 + 1) | |
34 | #define FAT_MAX_UNI_SIZE (FAT_MAX_UNI_CHARS * sizeof(wchar_t)) | |
35 | ||
deb8274a SM |
36 | static inline unsigned char fat_tolower(unsigned char c) |
37 | { | |
38 | return ((c >= 'A') && (c <= 'Z')) ? c+32 : c; | |
39 | } | |
40 | ||
1da177e4 LT |
41 | static inline loff_t fat_make_i_pos(struct super_block *sb, |
42 | struct buffer_head *bh, | |
43 | struct msdos_dir_entry *de) | |
44 | { | |
45 | return ((loff_t)bh->b_blocknr << MSDOS_SB(sb)->dir_per_block_bits) | |
46 | | (de - (struct msdos_dir_entry *)bh->b_data); | |
47 | } | |
48 | ||
f3ef6f63 KW |
49 | static inline void fat_dir_readahead(struct inode *dir, sector_t iblock, |
50 | sector_t phys) | |
51 | { | |
52 | struct super_block *sb = dir->i_sb; | |
53 | struct msdos_sb_info *sbi = MSDOS_SB(sb); | |
54 | struct buffer_head *bh; | |
55 | int sec; | |
56 | ||
57 | /* This is not a first sector of cluster, or sec_per_clus == 1 */ | |
58 | if ((iblock & (sbi->sec_per_clus - 1)) || sbi->sec_per_clus == 1) | |
59 | return; | |
60 | /* root dir of FAT12/FAT16 */ | |
306790f7 | 61 | if (!is_fat32(sbi) && (dir->i_ino == MSDOS_ROOT_INO)) |
f3ef6f63 KW |
62 | return; |
63 | ||
83b7c996 OH |
64 | bh = sb_find_get_block(sb, phys); |
65 | if (bh == NULL || !buffer_uptodate(bh)) { | |
f3ef6f63 KW |
66 | for (sec = 0; sec < sbi->sec_per_clus; sec++) |
67 | sb_breadahead(sb, phys + sec); | |
68 | } | |
69 | brelse(bh); | |
70 | } | |
71 | ||
1da177e4 LT |
72 | /* Returns the inode number of the directory entry at offset pos. If bh is |
73 | non-NULL, it is brelse'd before. Pos is incremented. The buffer header is | |
74 | returned in bh. | |
75 | AV. Most often we do it item-by-item. Makes sense to optimize. | |
76 | AV. OK, there we go: if both bh and de are non-NULL we assume that we just | |
77 | AV. want the next entry (took one explicit de=NULL in vfat/namei.c). | |
78 | AV. It's done in fat_get_entry() (inlined), here the slow case lives. | |
79 | AV. Additionally, when we return -1 (i.e. reached the end of directory) | |
80 | AV. we make bh NULL. | |
81 | */ | |
82 | static int fat__get_entry(struct inode *dir, loff_t *pos, | |
83 | struct buffer_head **bh, struct msdos_dir_entry **de) | |
84 | { | |
85 | struct super_block *sb = dir->i_sb; | |
86 | sector_t phys, iblock; | |
e5174baa OH |
87 | unsigned long mapped_blocks; |
88 | int err, offset; | |
1da177e4 LT |
89 | |
90 | next: | |
aadc4e01 | 91 | brelse(*bh); |
1da177e4 LT |
92 | *bh = NULL; |
93 | iblock = *pos >> sb->s_blocksize_bits; | |
16fab201 | 94 | err = fat_bmap(dir, iblock, &phys, &mapped_blocks, 0, false); |
1da177e4 LT |
95 | if (err || !phys) |
96 | return -1; /* beyond EOF or error */ | |
97 | ||
f3ef6f63 KW |
98 | fat_dir_readahead(dir, iblock, phys); |
99 | ||
1da177e4 LT |
100 | *bh = sb_bread(sb, phys); |
101 | if (*bh == NULL) { | |
f0aac616 NJ |
102 | fat_msg_ratelimit(sb, KERN_ERR, |
103 | "Directory bread(block %llu) failed", (llu)phys); | |
1da177e4 LT |
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 && | |
f08b4988 CJB |
122 | (*de - (struct msdos_dir_entry *)(*bh)->b_data) < |
123 | MSDOS_SB(dir->i_sb)->dir_per_block - 1) { | |
1da177e4 LT |
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 | /* | |
4de151d8 | 132 | * Convert Unicode 16 to UTF-8, translated Unicode, or ASCII. |
1da177e4 LT |
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 | */ | |
869f58c0 AF |
141 | static int uni16_to_x8(struct super_block *sb, unsigned char *ascii, |
142 | const wchar_t *uni, int len, struct nls_table *nls) | |
1da177e4 | 143 | { |
869f58c0 | 144 | int uni_xlate = MSDOS_SB(sb)->options.unicode_xlate; |
d6886116 OH |
145 | const wchar_t *ip; |
146 | wchar_t ec; | |
3ed3dec1 | 147 | unsigned char *op; |
1da177e4 | 148 | int charlen; |
1da177e4 LT |
149 | |
150 | ip = uni; | |
151 | op = ascii; | |
152 | ||
f22032ba | 153 | while (*ip && ((len - NLS_MAX_CHARSET_SIZE) > 0)) { |
1da177e4 | 154 | ec = *ip++; |
f08b4988 CJB |
155 | charlen = nls->uni2char(ec, op, NLS_MAX_CHARSET_SIZE); |
156 | if (charlen > 0) { | |
1da177e4 | 157 | op += charlen; |
f22032ba | 158 | len -= charlen; |
1da177e4 LT |
159 | } else { |
160 | if (uni_xlate == 1) { | |
3ed3dec1 | 161 | *op++ = ':'; |
0a90e0f1 AS |
162 | op = hex_byte_pack(op, ec >> 8); |
163 | op = hex_byte_pack(op, ec); | |
f22032ba | 164 | len -= 5; |
1da177e4 LT |
165 | } else { |
166 | *op++ = '?'; | |
f22032ba | 167 | len--; |
1da177e4 LT |
168 | } |
169 | } | |
1da177e4 | 170 | } |
f22032ba KM |
171 | |
172 | if (unlikely(*ip)) { | |
f08b4988 CJB |
173 | fat_msg(sb, KERN_WARNING, |
174 | "filename was truncated while converting."); | |
f22032ba KM |
175 | } |
176 | ||
1da177e4 | 177 | *op = 0; |
f08b4988 | 178 | return op - ascii; |
1da177e4 LT |
179 | } |
180 | ||
869f58c0 | 181 | static inline int fat_uni_to_x8(struct super_block *sb, const wchar_t *uni, |
d6886116 OH |
182 | unsigned char *buf, int size) |
183 | { | |
869f58c0 | 184 | struct msdos_sb_info *sbi = MSDOS_SB(sb); |
d6886116 | 185 | if (sbi->options.utf8) |
74675a58 AS |
186 | return utf16s_to_utf8s(uni, FAT_MAX_UNI_CHARS, |
187 | UTF16_HOST_ENDIAN, buf, size); | |
d6886116 | 188 | else |
869f58c0 | 189 | return uni16_to_x8(sb, buf, uni, size, sbi->nls_io); |
d6886116 OH |
190 | } |
191 | ||
1da177e4 LT |
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 | |
f08b4988 CJB |
206 | fat_short2lower_uni(struct nls_table *t, unsigned char *c, |
207 | int clen, wchar_t *uni) | |
1da177e4 LT |
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 | ||
f08b4988 CJB |
222 | charlen = t->char2uni(&nc, 1, uni); |
223 | if (charlen < 0) { | |
1da177e4 LT |
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 | * | |
4d9784c0 YL |
272 | * @dir: Pointer to the inode that represents the directory. |
273 | * @pos: On input, contains the starting position to read from. | |
274 | * On output, updated with the new position. | |
275 | * @bh: Pointer to the buffer head that may be used for reading directory | |
276 | * entries. May be updated. | |
277 | * @de: On input, points to the current directory entry. | |
278 | * On output, points to the next directory entry. | |
279 | * @unicode: Pointer to a buffer where the parsed Unicode long filename will be | |
280 | * stored. | |
281 | * @nr_slots: Pointer to a variable that will store the number of longname | |
282 | * slots found. | |
283 | * | |
ad2c1604 PE |
284 | * This function returns zero on success, negative value on error, or one of |
285 | * the following: | |
286 | * | |
287 | * %PARSE_INVALID - Directory entry is invalid. | |
288 | * %PARSE_NOT_LONGNAME - Directory entry does not contain longname. | |
289 | * %PARSE_EOF - Directory has no more entries. | |
290 | */ | |
291 | static int fat_parse_long(struct inode *dir, loff_t *pos, | |
292 | struct buffer_head **bh, struct msdos_dir_entry **de, | |
293 | wchar_t **unicode, unsigned char *nr_slots) | |
294 | { | |
295 | struct msdos_dir_slot *ds; | |
296 | unsigned char id, slot, slots, alias_checksum; | |
297 | ||
298 | if (!*unicode) { | |
c7a6c4ed | 299 | *unicode = __getname(); |
ad2c1604 PE |
300 | if (!*unicode) { |
301 | brelse(*bh); | |
302 | return -ENOMEM; | |
303 | } | |
304 | } | |
305 | parse_long: | |
ad2c1604 PE |
306 | ds = (struct msdos_dir_slot *)*de; |
307 | id = ds->id; | |
308 | if (!(id & 0x40)) | |
309 | return PARSE_INVALID; | |
310 | slots = id & ~0x40; | |
311 | if (slots > 20 || !slots) /* ceil(256 * 2 / 26) */ | |
312 | return PARSE_INVALID; | |
313 | *nr_slots = slots; | |
314 | alias_checksum = ds->alias_checksum; | |
315 | ||
316 | slot = slots; | |
317 | while (1) { | |
318 | int offset; | |
319 | ||
320 | slot--; | |
321 | offset = slot * 13; | |
322 | fat16_towchar(*unicode + offset, ds->name0_4, 5); | |
323 | fat16_towchar(*unicode + offset + 5, ds->name5_10, 6); | |
324 | fat16_towchar(*unicode + offset + 11, ds->name11_12, 2); | |
325 | ||
326 | if (ds->id & 0x40) | |
327 | (*unicode)[offset + 13] = 0; | |
328 | if (fat_get_entry(dir, pos, bh, de) < 0) | |
329 | return PARSE_EOF; | |
330 | if (slot == 0) | |
331 | break; | |
332 | ds = (struct msdos_dir_slot *)*de; | |
333 | if (ds->attr != ATTR_EXT) | |
334 | return PARSE_NOT_LONGNAME; | |
335 | if ((ds->id & ~0x40) != slot) | |
336 | goto parse_long; | |
337 | if (ds->alias_checksum != alias_checksum) | |
338 | goto parse_long; | |
339 | } | |
340 | if ((*de)->name[0] == DELETED_FLAG) | |
341 | return PARSE_INVALID; | |
342 | if ((*de)->attr == ATTR_EXT) | |
343 | goto parse_long; | |
344 | if (IS_FREE((*de)->name) || ((*de)->attr & ATTR_VOLUME)) | |
345 | return PARSE_INVALID; | |
346 | if (fat_checksum((*de)->name) != alias_checksum) | |
347 | *nr_slots = 0; | |
348 | ||
349 | return 0; | |
350 | } | |
351 | ||
deb8274a SM |
352 | /** |
353 | * fat_parse_short - Parse MS-DOS (short) directory entry. | |
354 | * @sb: superblock | |
355 | * @de: directory entry to parse | |
356 | * @name: FAT_MAX_SHORT_SIZE array in which to place extracted name | |
357 | * @dot_hidden: Nonzero == prepend '.' to names with ATTR_HIDDEN | |
358 | * | |
359 | * Returns the number of characters extracted into 'name'. | |
360 | */ | |
361 | static int fat_parse_short(struct super_block *sb, | |
362 | const struct msdos_dir_entry *de, | |
363 | unsigned char *name, int dot_hidden) | |
364 | { | |
365 | const struct msdos_sb_info *sbi = MSDOS_SB(sb); | |
366 | int isvfat = sbi->options.isvfat; | |
367 | int nocase = sbi->options.nocase; | |
368 | unsigned short opt_shortname = sbi->options.shortname; | |
369 | struct nls_table *nls_disk = sbi->nls_disk; | |
370 | wchar_t uni_name[14]; | |
371 | unsigned char c, work[MSDOS_NAME]; | |
372 | unsigned char *ptname = name; | |
373 | int chi, chl, i, j, k; | |
374 | int dotoffset = 0; | |
375 | int name_len = 0, uni_len = 0; | |
376 | ||
377 | if (!isvfat && dot_hidden && (de->attr & ATTR_HIDDEN)) { | |
378 | *ptname++ = '.'; | |
379 | dotoffset = 1; | |
380 | } | |
381 | ||
382 | memcpy(work, de->name, sizeof(work)); | |
eceb8902 MM |
383 | /* For an explanation of the special treatment of 0x05 in |
384 | * filenames, see msdos_format_name in namei_msdos.c | |
385 | */ | |
deb8274a SM |
386 | if (work[0] == 0x05) |
387 | work[0] = 0xE5; | |
388 | ||
389 | /* Filename */ | |
390 | for (i = 0, j = 0; i < 8;) { | |
391 | c = work[i]; | |
392 | if (!c) | |
393 | break; | |
394 | chl = fat_shortname2uni(nls_disk, &work[i], 8 - i, | |
395 | &uni_name[j++], opt_shortname, | |
396 | de->lcase & CASE_LOWER_BASE); | |
397 | if (chl <= 1) { | |
398 | if (!isvfat) | |
399 | ptname[i] = nocase ? c : fat_tolower(c); | |
400 | i++; | |
401 | if (c != ' ') { | |
402 | name_len = i; | |
403 | uni_len = j; | |
404 | } | |
405 | } else { | |
406 | uni_len = j; | |
407 | if (isvfat) | |
408 | i += min(chl, 8-i); | |
409 | else { | |
410 | for (chi = 0; chi < chl && i < 8; chi++, i++) | |
411 | ptname[i] = work[i]; | |
412 | } | |
413 | if (chl) | |
414 | name_len = i; | |
415 | } | |
416 | } | |
417 | ||
418 | i = name_len; | |
419 | j = uni_len; | |
420 | fat_short2uni(nls_disk, ".", 1, &uni_name[j++]); | |
421 | if (!isvfat) | |
422 | ptname[i] = '.'; | |
423 | i++; | |
424 | ||
425 | /* Extension */ | |
426 | for (k = 8; k < MSDOS_NAME;) { | |
427 | c = work[k]; | |
428 | if (!c) | |
429 | break; | |
430 | chl = fat_shortname2uni(nls_disk, &work[k], MSDOS_NAME - k, | |
431 | &uni_name[j++], opt_shortname, | |
432 | de->lcase & CASE_LOWER_EXT); | |
433 | if (chl <= 1) { | |
434 | k++; | |
435 | if (!isvfat) | |
436 | ptname[i] = nocase ? c : fat_tolower(c); | |
437 | i++; | |
438 | if (c != ' ') { | |
439 | name_len = i; | |
440 | uni_len = j; | |
441 | } | |
442 | } else { | |
443 | uni_len = j; | |
444 | if (isvfat) { | |
445 | int offset = min(chl, MSDOS_NAME-k); | |
446 | k += offset; | |
447 | i += offset; | |
448 | } else { | |
449 | for (chi = 0; chi < chl && k < MSDOS_NAME; | |
450 | chi++, i++, k++) { | |
451 | ptname[i] = work[k]; | |
452 | } | |
453 | } | |
454 | if (chl) | |
455 | name_len = i; | |
456 | } | |
457 | } | |
458 | ||
459 | if (name_len > 0) { | |
460 | name_len += dotoffset; | |
461 | ||
462 | if (sbi->options.isvfat) { | |
463 | uni_name[uni_len] = 0x0000; | |
464 | name_len = fat_uni_to_x8(sb, uni_name, name, | |
465 | FAT_MAX_SHORT_SIZE); | |
466 | } | |
467 | } | |
468 | ||
469 | return name_len; | |
470 | } | |
471 | ||
1da177e4 | 472 | /* |
c39540c6 | 473 | * Return values: negative -> error/not found, 0 -> found. |
1da177e4 LT |
474 | */ |
475 | int fat_search_long(struct inode *inode, const unsigned char *name, | |
476 | int name_len, struct fat_slot_info *sinfo) | |
477 | { | |
478 | struct super_block *sb = inode->i_sb; | |
479 | struct msdos_sb_info *sbi = MSDOS_SB(sb); | |
480 | struct buffer_head *bh = NULL; | |
481 | struct msdos_dir_entry *de; | |
f22032ba | 482 | unsigned char nr_slots; |
1da177e4 | 483 | wchar_t *unicode = NULL; |
98a15160 | 484 | unsigned char bufname[FAT_MAX_SHORT_SIZE]; |
1da177e4 | 485 | loff_t cpos = 0; |
deb8274a | 486 | int err, len; |
1da177e4 LT |
487 | |
488 | err = -ENOENT; | |
d6886116 | 489 | while (1) { |
1da177e4 | 490 | if (fat_get_entry(inode, &cpos, &bh, &de) == -1) |
d6886116 | 491 | goto end_of_dir; |
1da177e4 LT |
492 | parse_record: |
493 | nr_slots = 0; | |
494 | if (de->name[0] == DELETED_FLAG) | |
495 | continue; | |
496 | if (de->attr != ATTR_EXT && (de->attr & ATTR_VOLUME)) | |
497 | continue; | |
498 | if (de->attr != ATTR_EXT && IS_FREE(de->name)) | |
499 | continue; | |
500 | if (de->attr == ATTR_EXT) { | |
ad2c1604 PE |
501 | int status = fat_parse_long(inode, &cpos, &bh, &de, |
502 | &unicode, &nr_slots); | |
52e9d9f4 DJ |
503 | if (status < 0) { |
504 | err = status; | |
505 | goto end_of_dir; | |
506 | } else if (status == PARSE_INVALID) | |
1da177e4 | 507 | continue; |
ad2c1604 PE |
508 | else if (status == PARSE_NOT_LONGNAME) |
509 | goto parse_record; | |
510 | else if (status == PARSE_EOF) | |
d6886116 | 511 | goto end_of_dir; |
1da177e4 LT |
512 | } |
513 | ||
deb8274a SM |
514 | /* Never prepend '.' to hidden files here. |
515 | * That is done only for msdos mounts (and only when | |
516 | * 'dotsOK=yes'); if we are executing here, it is in the | |
517 | * context of a vfat mount. | |
518 | */ | |
519 | len = fat_parse_short(sb, de, bufname, 0); | |
520 | if (len == 0) | |
1da177e4 LT |
521 | continue; |
522 | ||
d6886116 | 523 | /* Compare shortname */ |
d6886116 OH |
524 | if (fat_name_match(sbi, name, name_len, bufname, len)) |
525 | goto found; | |
1da177e4 LT |
526 | |
527 | if (nr_slots) { | |
98a15160 OH |
528 | void *longname = unicode + FAT_MAX_UNI_CHARS; |
529 | int size = PATH_MAX - FAT_MAX_UNI_SIZE; | |
530 | ||
d6886116 | 531 | /* Compare longname */ |
869f58c0 | 532 | len = fat_uni_to_x8(sb, unicode, longname, size); |
98a15160 | 533 | if (fat_name_match(sbi, name, name_len, longname, len)) |
d6886116 | 534 | goto found; |
1da177e4 LT |
535 | } |
536 | } | |
537 | ||
d6886116 | 538 | found: |
1da177e4 LT |
539 | nr_slots++; /* include the de */ |
540 | sinfo->slot_off = cpos - nr_slots * sizeof(*de); | |
541 | sinfo->nr_slots = nr_slots; | |
542 | sinfo->de = de; | |
543 | sinfo->bh = bh; | |
544 | sinfo->i_pos = fat_make_i_pos(sb, sinfo->bh, sinfo->de); | |
545 | err = 0; | |
d6886116 | 546 | end_of_dir: |
1da177e4 | 547 | if (unicode) |
c7a6c4ed | 548 | __putname(unicode); |
1da177e4 LT |
549 | |
550 | return err; | |
551 | } | |
7c709d00 | 552 | EXPORT_SYMBOL_GPL(fat_search_long); |
1da177e4 LT |
553 | |
554 | struct fat_ioctl_filldir_callback { | |
2c6a2473 | 555 | struct dir_context ctx; |
c483bab0 | 556 | void __user *dirent; |
1da177e4 LT |
557 | int result; |
558 | /* for dir ioctl */ | |
559 | const char *longname; | |
560 | int long_len; | |
561 | const char *shortname; | |
562 | int short_len; | |
563 | }; | |
564 | ||
2c6a2473 AV |
565 | static int __fat_readdir(struct inode *inode, struct file *file, |
566 | struct dir_context *ctx, int short_only, | |
567 | struct fat_ioctl_filldir_callback *both) | |
1da177e4 LT |
568 | { |
569 | struct super_block *sb = inode->i_sb; | |
570 | struct msdos_sb_info *sbi = MSDOS_SB(sb); | |
571 | struct buffer_head *bh; | |
572 | struct msdos_dir_entry *de; | |
d6886116 | 573 | unsigned char nr_slots; |
1da177e4 | 574 | wchar_t *unicode = NULL; |
deb8274a | 575 | unsigned char bufname[FAT_MAX_SHORT_SIZE]; |
1da177e4 | 576 | int isvfat = sbi->options.isvfat; |
dcd8c53f | 577 | const char *fill_name = NULL; |
2c6a2473 | 578 | int fake_offset = 0; |
1da177e4 | 579 | loff_t cpos; |
deb8274a | 580 | int short_len = 0, fill_len = 0; |
1da177e4 LT |
581 | int ret = 0; |
582 | ||
e40b34c7 | 583 | mutex_lock(&sbi->s_lock); |
1da177e4 | 584 | |
2c6a2473 | 585 | cpos = ctx->pos; |
1da177e4 LT |
586 | /* Fake . and .. for the root directory. */ |
587 | if (inode->i_ino == MSDOS_ROOT_INO) { | |
2c6a2473 AV |
588 | if (!dir_emit_dots(file, ctx)) |
589 | goto out; | |
590 | if (ctx->pos == 2) { | |
591 | fake_offset = 1; | |
1da177e4 LT |
592 | cpos = 0; |
593 | } | |
594 | } | |
d6886116 | 595 | if (cpos & (sizeof(struct msdos_dir_entry) - 1)) { |
1da177e4 LT |
596 | ret = -ENOENT; |
597 | goto out; | |
598 | } | |
599 | ||
600 | bh = NULL; | |
d6886116 | 601 | get_new: |
1da177e4 | 602 | if (fat_get_entry(inode, &cpos, &bh, &de) == -1) |
d6886116 | 603 | goto end_of_dir; |
ad2c1604 | 604 | parse_record: |
d6886116 | 605 | nr_slots = 0; |
dcd8c53f OH |
606 | /* |
607 | * Check for long filename entry, but if short_only, we don't | |
608 | * need to parse long filename. | |
609 | */ | |
610 | if (isvfat && !short_only) { | |
1da177e4 | 611 | if (de->name[0] == DELETED_FLAG) |
d6886116 | 612 | goto record_end; |
1da177e4 | 613 | if (de->attr != ATTR_EXT && (de->attr & ATTR_VOLUME)) |
d6886116 | 614 | goto record_end; |
1da177e4 | 615 | if (de->attr != ATTR_EXT && IS_FREE(de->name)) |
d6886116 | 616 | goto record_end; |
1da177e4 LT |
617 | } else { |
618 | if ((de->attr & ATTR_VOLUME) || IS_FREE(de->name)) | |
d6886116 | 619 | goto record_end; |
1da177e4 LT |
620 | } |
621 | ||
622 | if (isvfat && de->attr == ATTR_EXT) { | |
ad2c1604 | 623 | int status = fat_parse_long(inode, &cpos, &bh, &de, |
d6886116 | 624 | &unicode, &nr_slots); |
ad2c1604 | 625 | if (status < 0) { |
928a4771 | 626 | bh = NULL; |
ad2c1604 | 627 | ret = status; |
928a4771 | 628 | goto end_of_dir; |
ad2c1604 | 629 | } else if (status == PARSE_INVALID) |
d6886116 | 630 | goto record_end; |
ad2c1604 PE |
631 | else if (status == PARSE_NOT_LONGNAME) |
632 | goto parse_record; | |
633 | else if (status == PARSE_EOF) | |
d6886116 | 634 | goto end_of_dir; |
dcd8c53f OH |
635 | |
636 | if (nr_slots) { | |
637 | void *longname = unicode + FAT_MAX_UNI_CHARS; | |
638 | int size = PATH_MAX - FAT_MAX_UNI_SIZE; | |
869f58c0 | 639 | int len = fat_uni_to_x8(sb, unicode, longname, size); |
dcd8c53f OH |
640 | |
641 | fill_name = longname; | |
642 | fill_len = len; | |
643 | /* !both && !short_only, so we don't need shortname. */ | |
644 | if (!both) | |
645 | goto start_filldir; | |
2c6a2473 AV |
646 | |
647 | short_len = fat_parse_short(sb, de, bufname, | |
648 | sbi->options.dotsOK); | |
649 | if (short_len == 0) | |
650 | goto record_end; | |
651 | /* hack for fat_ioctl_filldir() */ | |
652 | both->longname = fill_name; | |
653 | both->long_len = fill_len; | |
654 | both->shortname = bufname; | |
655 | both->short_len = short_len; | |
656 | fill_name = NULL; | |
657 | fill_len = 0; | |
658 | goto start_filldir; | |
dcd8c53f | 659 | } |
1da177e4 LT |
660 | } |
661 | ||
deb8274a SM |
662 | short_len = fat_parse_short(sb, de, bufname, sbi->options.dotsOK); |
663 | if (short_len == 0) | |
d6886116 | 664 | goto record_end; |
1da177e4 | 665 | |
2c6a2473 AV |
666 | fill_name = bufname; |
667 | fill_len = short_len; | |
dcd8c53f OH |
668 | |
669 | start_filldir: | |
928a4771 OH |
670 | ctx->pos = cpos - (nr_slots + 1) * sizeof(struct msdos_dir_entry); |
671 | if (fake_offset && ctx->pos < 2) | |
672 | ctx->pos = 2; | |
2c6a2473 AV |
673 | |
674 | if (!memcmp(de->name, MSDOS_DOT, MSDOS_NAME)) { | |
675 | if (!dir_emit_dot(file, ctx)) | |
676 | goto fill_failed; | |
677 | } else if (!memcmp(de->name, MSDOS_DOTDOT, MSDOS_NAME)) { | |
678 | if (!dir_emit_dotdot(file, ctx)) | |
679 | goto fill_failed; | |
1da177e4 | 680 | } else { |
2c6a2473 | 681 | unsigned long inum; |
1da177e4 LT |
682 | loff_t i_pos = fat_make_i_pos(sb, bh, de); |
683 | struct inode *tmp = fat_iget(sb, i_pos); | |
684 | if (tmp) { | |
685 | inum = tmp->i_ino; | |
686 | iput(tmp); | |
687 | } else | |
688 | inum = iunique(sb, MSDOS_ROOT_INO); | |
2c6a2473 AV |
689 | if (!dir_emit(ctx, fill_name, fill_len, inum, |
690 | (de->attr & ATTR_DIR) ? DT_DIR : DT_REG)) | |
691 | goto fill_failed; | |
1da177e4 LT |
692 | } |
693 | ||
d6886116 | 694 | record_end: |
2c6a2473 AV |
695 | fake_offset = 0; |
696 | ctx->pos = cpos; | |
d6886116 | 697 | goto get_new; |
928a4771 | 698 | |
d6886116 | 699 | end_of_dir: |
928a4771 OH |
700 | if (fake_offset && cpos < 2) |
701 | ctx->pos = 2; | |
702 | else | |
703 | ctx->pos = cpos; | |
d6886116 | 704 | fill_failed: |
f3ef6f63 | 705 | brelse(bh); |
1da177e4 | 706 | if (unicode) |
c7a6c4ed | 707 | __putname(unicode); |
1da177e4 | 708 | out: |
e40b34c7 | 709 | mutex_unlock(&sbi->s_lock); |
928a4771 | 710 | |
1da177e4 LT |
711 | return ret; |
712 | } | |
713 | ||
2c6a2473 | 714 | static int fat_readdir(struct file *file, struct dir_context *ctx) |
1da177e4 | 715 | { |
2c6a2473 | 716 | return __fat_readdir(file_inode(file), file, ctx, 0, NULL); |
1da177e4 LT |
717 | } |
718 | ||
c483bab0 | 719 | #define FAT_IOCTL_FILLDIR_FUNC(func, dirent_type) \ |
25885a35 | 720 | static bool func(struct dir_context *ctx, const char *name, int name_len, \ |
c483bab0 OH |
721 | loff_t offset, u64 ino, unsigned int d_type) \ |
722 | { \ | |
ac7576f4 MS |
723 | struct fat_ioctl_filldir_callback *buf = \ |
724 | container_of(ctx, struct fat_ioctl_filldir_callback, ctx); \ | |
c483bab0 OH |
725 | struct dirent_type __user *d1 = buf->dirent; \ |
726 | struct dirent_type __user *d2 = d1 + 1; \ | |
727 | \ | |
728 | if (buf->result) \ | |
25885a35 | 729 | return false; \ |
c483bab0 OH |
730 | buf->result++; \ |
731 | \ | |
732 | if (name != NULL) { \ | |
733 | /* dirent has only short name */ \ | |
734 | if (name_len >= sizeof(d1->d_name)) \ | |
735 | name_len = sizeof(d1->d_name) - 1; \ | |
736 | \ | |
2cd50532 | 737 | if (put_user(0, &d2->d_name[0]) || \ |
c483bab0 OH |
738 | put_user(0, &d2->d_reclen) || \ |
739 | copy_to_user(d1->d_name, name, name_len) || \ | |
740 | put_user(0, d1->d_name + name_len) || \ | |
741 | put_user(name_len, &d1->d_reclen)) \ | |
742 | goto efault; \ | |
743 | } else { \ | |
744 | /* dirent has short and long name */ \ | |
745 | const char *longname = buf->longname; \ | |
746 | int long_len = buf->long_len; \ | |
747 | const char *shortname = buf->shortname; \ | |
748 | int short_len = buf->short_len; \ | |
749 | \ | |
750 | if (long_len >= sizeof(d1->d_name)) \ | |
751 | long_len = sizeof(d1->d_name) - 1; \ | |
752 | if (short_len >= sizeof(d1->d_name)) \ | |
753 | short_len = sizeof(d1->d_name) - 1; \ | |
754 | \ | |
755 | if (copy_to_user(d2->d_name, longname, long_len) || \ | |
756 | put_user(0, d2->d_name + long_len) || \ | |
757 | put_user(long_len, &d2->d_reclen) || \ | |
758 | put_user(ino, &d2->d_ino) || \ | |
759 | put_user(offset, &d2->d_off) || \ | |
760 | copy_to_user(d1->d_name, shortname, short_len) || \ | |
761 | put_user(0, d1->d_name + short_len) || \ | |
762 | put_user(short_len, &d1->d_reclen)) \ | |
763 | goto efault; \ | |
764 | } \ | |
25885a35 | 765 | return true; \ |
c483bab0 OH |
766 | efault: \ |
767 | buf->result = -EFAULT; \ | |
25885a35 | 768 | return false; \ |
c483bab0 OH |
769 | } |
770 | ||
531f710f | 771 | FAT_IOCTL_FILLDIR_FUNC(fat_ioctl_filldir, __fat_dirent) |
c483bab0 | 772 | |
2c6a2473 | 773 | static int fat_ioctl_readdir(struct inode *inode, struct file *file, |
c483bab0 OH |
774 | void __user *dirent, filldir_t filldir, |
775 | int short_only, int both) | |
1da177e4 | 776 | { |
2c6a2473 AV |
777 | struct fat_ioctl_filldir_callback buf = { |
778 | .ctx.actor = filldir, | |
779 | .dirent = dirent | |
780 | }; | |
c483bab0 OH |
781 | int ret; |
782 | ||
783 | buf.dirent = dirent; | |
784 | buf.result = 0; | |
98d4b8d8 | 785 | inode_lock_shared(inode); |
2c6a2473 | 786 | buf.ctx.pos = file->f_pos; |
c483bab0 OH |
787 | ret = -ENOENT; |
788 | if (!IS_DEADDIR(inode)) { | |
2c6a2473 AV |
789 | ret = __fat_readdir(inode, file, &buf.ctx, |
790 | short_only, both ? &buf : NULL); | |
791 | file->f_pos = buf.ctx.pos; | |
1da177e4 | 792 | } |
98d4b8d8 | 793 | inode_unlock_shared(inode); |
c483bab0 OH |
794 | if (ret >= 0) |
795 | ret = buf.result; | |
796 | return ret; | |
1da177e4 LT |
797 | } |
798 | ||
7845bc3e AB |
799 | static long fat_dir_ioctl(struct file *filp, unsigned int cmd, |
800 | unsigned long arg) | |
1da177e4 | 801 | { |
496ad9aa | 802 | struct inode *inode = file_inode(filp); |
531f710f | 803 | struct __fat_dirent __user *d1 = (struct __fat_dirent __user *)arg; |
c483bab0 | 804 | int short_only, both; |
1da177e4 LT |
805 | |
806 | switch (cmd) { | |
807 | case VFAT_IOCTL_READDIR_SHORT: | |
808 | short_only = 1; | |
809 | both = 0; | |
810 | break; | |
811 | case VFAT_IOCTL_READDIR_BOTH: | |
812 | short_only = 0; | |
813 | both = 1; | |
814 | break; | |
815 | default: | |
7845bc3e | 816 | return fat_generic_ioctl(filp, cmd, arg); |
1da177e4 LT |
817 | } |
818 | ||
1da177e4 LT |
819 | /* |
820 | * Yes, we don't need this put_user() absolutely. However old | |
821 | * code didn't return the right value. So, app use this value, | |
822 | * in order to check whether it is EOF. | |
823 | */ | |
824 | if (put_user(0, &d1->d_reclen)) | |
825 | return -EFAULT; | |
826 | ||
c483bab0 OH |
827 | return fat_ioctl_readdir(inode, filp, d1, fat_ioctl_filldir, |
828 | short_only, both); | |
1da177e4 LT |
829 | } |
830 | ||
188f83df DH |
831 | #ifdef CONFIG_COMPAT |
832 | #define VFAT_IOCTL_READDIR_BOTH32 _IOR('r', 1, struct compat_dirent[2]) | |
833 | #define VFAT_IOCTL_READDIR_SHORT32 _IOR('r', 2, struct compat_dirent[2]) | |
834 | ||
c483bab0 | 835 | FAT_IOCTL_FILLDIR_FUNC(fat_compat_ioctl_filldir, compat_dirent) |
188f83df | 836 | |
c483bab0 | 837 | static long fat_compat_dir_ioctl(struct file *filp, unsigned cmd, |
188f83df DH |
838 | unsigned long arg) |
839 | { | |
496ad9aa | 840 | struct inode *inode = file_inode(filp); |
c483bab0 OH |
841 | struct compat_dirent __user *d1 = compat_ptr(arg); |
842 | int short_only, both; | |
188f83df DH |
843 | |
844 | switch (cmd) { | |
188f83df | 845 | case VFAT_IOCTL_READDIR_SHORT32: |
c483bab0 OH |
846 | short_only = 1; |
847 | both = 0; | |
848 | break; | |
849 | case VFAT_IOCTL_READDIR_BOTH32: | |
850 | short_only = 0; | |
851 | both = 1; | |
188f83df DH |
852 | break; |
853 | default: | |
7845bc3e | 854 | return fat_generic_ioctl(filp, cmd, (unsigned long)arg); |
188f83df DH |
855 | } |
856 | ||
c483bab0 OH |
857 | /* |
858 | * Yes, we don't need this put_user() absolutely. However old | |
859 | * code didn't return the right value. So, app use this value, | |
860 | * in order to check whether it is EOF. | |
861 | */ | |
862 | if (put_user(0, &d1->d_reclen)) | |
863 | return -EFAULT; | |
864 | ||
865 | return fat_ioctl_readdir(inode, filp, d1, fat_compat_ioctl_filldir, | |
866 | short_only, both); | |
188f83df DH |
867 | } |
868 | #endif /* CONFIG_COMPAT */ | |
869 | ||
4b6f5d20 | 870 | const struct file_operations fat_dir_operations = { |
53472bc8 | 871 | .llseek = generic_file_llseek, |
1da177e4 | 872 | .read = generic_read_dir, |
98d4b8d8 | 873 | .iterate_shared = fat_readdir, |
7845bc3e | 874 | .unlocked_ioctl = fat_dir_ioctl, |
188f83df DH |
875 | #ifdef CONFIG_COMPAT |
876 | .compat_ioctl = fat_compat_dir_ioctl, | |
877 | #endif | |
b522412a | 878 | .fsync = fat_file_fsync, |
1da177e4 LT |
879 | }; |
880 | ||
881 | static int fat_get_short_entry(struct inode *dir, loff_t *pos, | |
882 | struct buffer_head **bh, | |
883 | struct msdos_dir_entry **de) | |
884 | { | |
885 | while (fat_get_entry(dir, pos, bh, de) >= 0) { | |
886 | /* free entry or long name entry or volume label */ | |
887 | if (!IS_FREE((*de)->name) && !((*de)->attr & ATTR_VOLUME)) | |
888 | return 0; | |
889 | } | |
890 | return -ENOENT; | |
891 | } | |
892 | ||
893 | /* | |
7669e8fb SM |
894 | * The ".." entry can not provide the "struct fat_slot_info" information |
895 | * for inode, nor a usable i_pos. So, this function provides some information | |
896 | * only. | |
897 | * | |
898 | * Since this function walks through the on-disk inodes within a directory, | |
899 | * callers are responsible for taking any locks necessary to prevent the | |
900 | * directory from changing. | |
1da177e4 LT |
901 | */ |
902 | int fat_get_dotdot_entry(struct inode *dir, struct buffer_head **bh, | |
7669e8fb | 903 | struct msdos_dir_entry **de) |
1da177e4 | 904 | { |
7669e8fb | 905 | loff_t offset = 0; |
1da177e4 | 906 | |
7669e8fb | 907 | *de = NULL; |
1da177e4 | 908 | while (fat_get_short_entry(dir, &offset, bh, de) >= 0) { |
7669e8fb | 909 | if (!strncmp((*de)->name, MSDOS_DOTDOT, MSDOS_NAME)) |
1da177e4 | 910 | return 0; |
1da177e4 LT |
911 | } |
912 | return -ENOENT; | |
913 | } | |
7c709d00 | 914 | EXPORT_SYMBOL_GPL(fat_get_dotdot_entry); |
1da177e4 LT |
915 | |
916 | /* See if directory is empty */ | |
917 | int fat_dir_empty(struct inode *dir) | |
918 | { | |
919 | struct buffer_head *bh; | |
920 | struct msdos_dir_entry *de; | |
921 | loff_t cpos; | |
922 | int result = 0; | |
923 | ||
924 | bh = NULL; | |
925 | cpos = 0; | |
926 | while (fat_get_short_entry(dir, &cpos, &bh, &de) >= 0) { | |
927 | if (strncmp(de->name, MSDOS_DOT , MSDOS_NAME) && | |
928 | strncmp(de->name, MSDOS_DOTDOT, MSDOS_NAME)) { | |
929 | result = -ENOTEMPTY; | |
930 | break; | |
931 | } | |
932 | } | |
933 | brelse(bh); | |
934 | return result; | |
935 | } | |
7c709d00 | 936 | EXPORT_SYMBOL_GPL(fat_dir_empty); |
1da177e4 LT |
937 | |
938 | /* | |
939 | * fat_subdirs counts the number of sub-directories of dir. It can be run | |
940 | * on directories being created. | |
941 | */ | |
942 | int fat_subdirs(struct inode *dir) | |
943 | { | |
944 | struct buffer_head *bh; | |
945 | struct msdos_dir_entry *de; | |
946 | loff_t cpos; | |
947 | int count = 0; | |
948 | ||
949 | bh = NULL; | |
950 | cpos = 0; | |
951 | while (fat_get_short_entry(dir, &cpos, &bh, &de) >= 0) { | |
952 | if (de->attr & ATTR_DIR) | |
953 | count++; | |
954 | } | |
955 | brelse(bh); | |
956 | return count; | |
957 | } | |
958 | ||
959 | /* | |
960 | * Scans a directory for a given file (name points to its formatted name). | |
961 | * Returns an error code or zero. | |
962 | */ | |
963 | int fat_scan(struct inode *dir, const unsigned char *name, | |
964 | struct fat_slot_info *sinfo) | |
965 | { | |
966 | struct super_block *sb = dir->i_sb; | |
967 | ||
968 | sinfo->slot_off = 0; | |
969 | sinfo->bh = NULL; | |
970 | while (fat_get_short_entry(dir, &sinfo->slot_off, &sinfo->bh, | |
971 | &sinfo->de) >= 0) { | |
972 | if (!strncmp(sinfo->de->name, name, MSDOS_NAME)) { | |
973 | sinfo->slot_off -= sizeof(*sinfo->de); | |
974 | sinfo->nr_slots = 1; | |
975 | sinfo->i_pos = fat_make_i_pos(sb, sinfo->bh, sinfo->de); | |
976 | return 0; | |
977 | } | |
978 | } | |
979 | return -ENOENT; | |
980 | } | |
7c709d00 | 981 | EXPORT_SYMBOL_GPL(fat_scan); |
1da177e4 | 982 | |
f1e6fb0a NJ |
983 | /* |
984 | * Scans a directory for a given logstart. | |
985 | * Returns an error code or zero. | |
986 | */ | |
987 | int fat_scan_logstart(struct inode *dir, int i_logstart, | |
988 | struct fat_slot_info *sinfo) | |
989 | { | |
990 | struct super_block *sb = dir->i_sb; | |
991 | ||
992 | sinfo->slot_off = 0; | |
993 | sinfo->bh = NULL; | |
994 | while (fat_get_short_entry(dir, &sinfo->slot_off, &sinfo->bh, | |
995 | &sinfo->de) >= 0) { | |
996 | if (fat_get_start(MSDOS_SB(sb), sinfo->de) == i_logstart) { | |
997 | sinfo->slot_off -= sizeof(*sinfo->de); | |
998 | sinfo->nr_slots = 1; | |
999 | sinfo->i_pos = fat_make_i_pos(sb, sinfo->bh, sinfo->de); | |
1000 | return 0; | |
1001 | } | |
1002 | } | |
1003 | return -ENOENT; | |
1004 | } | |
1005 | ||
1da177e4 LT |
1006 | static int __fat_remove_entries(struct inode *dir, loff_t pos, int nr_slots) |
1007 | { | |
1008 | struct super_block *sb = dir->i_sb; | |
1009 | struct buffer_head *bh; | |
1010 | struct msdos_dir_entry *de, *endp; | |
1011 | int err = 0, orig_slots; | |
1012 | ||
1013 | while (nr_slots) { | |
1014 | bh = NULL; | |
1015 | if (fat_get_entry(dir, &pos, &bh, &de) < 0) { | |
1016 | err = -EIO; | |
1017 | break; | |
1018 | } | |
1019 | ||
1020 | orig_slots = nr_slots; | |
1021 | endp = (struct msdos_dir_entry *)(bh->b_data + sb->s_blocksize); | |
1022 | while (nr_slots && de < endp) { | |
1023 | de->name[0] = DELETED_FLAG; | |
1024 | de++; | |
1025 | nr_slots--; | |
1026 | } | |
b522412a | 1027 | mark_buffer_dirty_inode(bh, dir); |
1da177e4 LT |
1028 | if (IS_DIRSYNC(dir)) |
1029 | err = sync_dirty_buffer(bh); | |
1030 | brelse(bh); | |
1031 | if (err) | |
1032 | break; | |
1033 | ||
1034 | /* pos is *next* de's position, so this does `- sizeof(de)' */ | |
1035 | pos += ((orig_slots - nr_slots) * sizeof(*de)) - sizeof(*de); | |
1036 | } | |
1037 | ||
1038 | return err; | |
1039 | } | |
1040 | ||
1041 | int fat_remove_entries(struct inode *dir, struct fat_slot_info *sinfo) | |
1042 | { | |
869f58c0 | 1043 | struct super_block *sb = dir->i_sb; |
1da177e4 LT |
1044 | struct msdos_dir_entry *de; |
1045 | struct buffer_head *bh; | |
1046 | int err = 0, nr_slots; | |
1047 | ||
1048 | /* | |
1049 | * First stage: Remove the shortname. By this, the directory | |
1050 | * entry is removed. | |
1051 | */ | |
1052 | nr_slots = sinfo->nr_slots; | |
1053 | de = sinfo->de; | |
1054 | sinfo->de = NULL; | |
1055 | bh = sinfo->bh; | |
1056 | sinfo->bh = NULL; | |
1057 | while (nr_slots && de >= (struct msdos_dir_entry *)bh->b_data) { | |
1058 | de->name[0] = DELETED_FLAG; | |
1059 | de--; | |
1060 | nr_slots--; | |
1061 | } | |
b522412a | 1062 | mark_buffer_dirty_inode(bh, dir); |
1da177e4 LT |
1063 | if (IS_DIRSYNC(dir)) |
1064 | err = sync_dirty_buffer(bh); | |
1065 | brelse(bh); | |
1066 | if (err) | |
1067 | return err; | |
2489dbab | 1068 | inode_inc_iversion(dir); |
1da177e4 LT |
1069 | |
1070 | if (nr_slots) { | |
1071 | /* | |
1072 | * Second stage: remove the remaining longname slots. | |
1073 | * (This directory entry is already removed, and so return | |
1074 | * the success) | |
1075 | */ | |
1076 | err = __fat_remove_entries(dir, sinfo->slot_off, nr_slots); | |
1077 | if (err) { | |
869f58c0 AF |
1078 | fat_msg(sb, KERN_WARNING, |
1079 | "Couldn't remove the long name slots"); | |
1da177e4 LT |
1080 | } |
1081 | } | |
1082 | ||
cd83f6b1 | 1083 | fat_truncate_time(dir, NULL, S_ATIME|S_MTIME); |
1da177e4 LT |
1084 | if (IS_DIRSYNC(dir)) |
1085 | (void)fat_sync_inode(dir); | |
1086 | else | |
1087 | mark_inode_dirty(dir); | |
1088 | ||
1089 | return 0; | |
1090 | } | |
7c709d00 | 1091 | EXPORT_SYMBOL_GPL(fat_remove_entries); |
1da177e4 LT |
1092 | |
1093 | static int fat_zeroed_cluster(struct inode *dir, sector_t blknr, int nr_used, | |
1094 | struct buffer_head **bhs, int nr_bhs) | |
1095 | { | |
1096 | struct super_block *sb = dir->i_sb; | |
1097 | sector_t last_blknr = blknr + MSDOS_SB(sb)->sec_per_clus; | |
1098 | int err, i, n; | |
1099 | ||
1100 | /* Zeroing the unused blocks on this cluster */ | |
1101 | blknr += nr_used; | |
1102 | n = nr_used; | |
1103 | while (blknr < last_blknr) { | |
1104 | bhs[n] = sb_getblk(sb, blknr); | |
1105 | if (!bhs[n]) { | |
1106 | err = -ENOMEM; | |
1107 | goto error; | |
1108 | } | |
07bfa441 OH |
1109 | /* Avoid race with userspace read via bdev */ |
1110 | lock_buffer(bhs[n]); | |
1da177e4 LT |
1111 | memset(bhs[n]->b_data, 0, sb->s_blocksize); |
1112 | set_buffer_uptodate(bhs[n]); | |
07bfa441 | 1113 | unlock_buffer(bhs[n]); |
b522412a | 1114 | mark_buffer_dirty_inode(bhs[n], dir); |
1da177e4 LT |
1115 | |
1116 | n++; | |
1117 | blknr++; | |
1118 | if (n == nr_bhs) { | |
1119 | if (IS_DIRSYNC(dir)) { | |
1120 | err = fat_sync_bhs(bhs, n); | |
1121 | if (err) | |
1122 | goto error; | |
1123 | } | |
1124 | for (i = 0; i < n; i++) | |
1125 | brelse(bhs[i]); | |
1126 | n = 0; | |
1127 | } | |
1128 | } | |
1129 | if (IS_DIRSYNC(dir)) { | |
1130 | err = fat_sync_bhs(bhs, n); | |
1131 | if (err) | |
1132 | goto error; | |
1133 | } | |
1134 | for (i = 0; i < n; i++) | |
1135 | brelse(bhs[i]); | |
1136 | ||
1137 | return 0; | |
1138 | ||
1139 | error: | |
1140 | for (i = 0; i < n; i++) | |
1141 | bforget(bhs[i]); | |
1142 | return err; | |
1143 | } | |
1144 | ||
f423420c | 1145 | int fat_alloc_new_dir(struct inode *dir, struct timespec64 *ts) |
1da177e4 LT |
1146 | { |
1147 | struct super_block *sb = dir->i_sb; | |
1148 | struct msdos_sb_info *sbi = MSDOS_SB(sb); | |
1149 | struct buffer_head *bhs[MAX_BUF_PER_PAGE]; | |
1150 | struct msdos_dir_entry *de; | |
1151 | sector_t blknr; | |
1152 | __le16 date, time; | |
7decd1cb | 1153 | u8 time_cs; |
1da177e4 LT |
1154 | int err, cluster; |
1155 | ||
1156 | err = fat_alloc_clusters(dir, &cluster, 1); | |
1157 | if (err) | |
1158 | goto error; | |
1159 | ||
1160 | blknr = fat_clus_to_blknr(sbi, cluster); | |
1161 | bhs[0] = sb_getblk(sb, blknr); | |
1162 | if (!bhs[0]) { | |
1163 | err = -ENOMEM; | |
1164 | goto error_free; | |
1165 | } | |
1166 | ||
7decd1cb | 1167 | fat_time_unix2fat(sbi, ts, &time, &date, &time_cs); |
1da177e4 LT |
1168 | |
1169 | de = (struct msdos_dir_entry *)bhs[0]->b_data; | |
07bfa441 OH |
1170 | /* Avoid race with userspace read via bdev */ |
1171 | lock_buffer(bhs[0]); | |
1da177e4 LT |
1172 | /* filling the new directory slots ("." and ".." entries) */ |
1173 | memcpy(de[0].name, MSDOS_DOT, MSDOS_NAME); | |
1174 | memcpy(de[1].name, MSDOS_DOTDOT, MSDOS_NAME); | |
1175 | de->attr = de[1].attr = ATTR_DIR; | |
1176 | de[0].lcase = de[1].lcase = 0; | |
1177 | de[0].time = de[1].time = time; | |
1178 | de[0].date = de[1].date = date; | |
1da177e4 LT |
1179 | if (sbi->options.isvfat) { |
1180 | /* extra timestamps */ | |
1181 | de[0].ctime = de[1].ctime = time; | |
7decd1cb | 1182 | de[0].ctime_cs = de[1].ctime_cs = time_cs; |
1da177e4 LT |
1183 | de[0].adate = de[0].cdate = de[1].adate = de[1].cdate = date; |
1184 | } else { | |
1185 | de[0].ctime = de[1].ctime = 0; | |
7decd1cb | 1186 | de[0].ctime_cs = de[1].ctime_cs = 0; |
1da177e4 LT |
1187 | de[0].adate = de[0].cdate = de[1].adate = de[1].cdate = 0; |
1188 | } | |
4b637098 NJ |
1189 | fat_set_start(&de[0], cluster); |
1190 | fat_set_start(&de[1], MSDOS_I(dir)->i_logstart); | |
1da177e4 LT |
1191 | de[0].size = de[1].size = 0; |
1192 | memset(de + 2, 0, sb->s_blocksize - 2 * sizeof(*de)); | |
1193 | set_buffer_uptodate(bhs[0]); | |
07bfa441 | 1194 | unlock_buffer(bhs[0]); |
b522412a | 1195 | mark_buffer_dirty_inode(bhs[0], dir); |
1da177e4 LT |
1196 | |
1197 | err = fat_zeroed_cluster(dir, blknr, 1, bhs, MAX_BUF_PER_PAGE); | |
1198 | if (err) | |
1199 | goto error_free; | |
1200 | ||
1201 | return cluster; | |
1202 | ||
1203 | error_free: | |
1204 | fat_free_clusters(dir, cluster); | |
1205 | error: | |
1206 | return err; | |
1207 | } | |
7c709d00 | 1208 | EXPORT_SYMBOL_GPL(fat_alloc_new_dir); |
1da177e4 LT |
1209 | |
1210 | static int fat_add_new_entries(struct inode *dir, void *slots, int nr_slots, | |
1211 | int *nr_cluster, struct msdos_dir_entry **de, | |
1212 | struct buffer_head **bh, loff_t *i_pos) | |
1213 | { | |
1214 | struct super_block *sb = dir->i_sb; | |
1215 | struct msdos_sb_info *sbi = MSDOS_SB(sb); | |
1216 | struct buffer_head *bhs[MAX_BUF_PER_PAGE]; | |
1217 | sector_t blknr, start_blknr, last_blknr; | |
1218 | unsigned long size, copy; | |
1219 | int err, i, n, offset, cluster[2]; | |
1220 | ||
1221 | /* | |
1222 | * The minimum cluster size is 512bytes, and maximum entry | |
1223 | * size is 32*slots (672bytes). So, iff the cluster size is | |
1224 | * 512bytes, we may need two clusters. | |
1225 | */ | |
1226 | size = nr_slots * sizeof(struct msdos_dir_entry); | |
1227 | *nr_cluster = (size + (sbi->cluster_size - 1)) >> sbi->cluster_bits; | |
1228 | BUG_ON(*nr_cluster > 2); | |
1229 | ||
1230 | err = fat_alloc_clusters(dir, cluster, *nr_cluster); | |
1231 | if (err) | |
1232 | goto error; | |
1233 | ||
1234 | /* | |
1235 | * First stage: Fill the directory entry. NOTE: This cluster | |
1236 | * is not referenced from any inode yet, so updates order is | |
1237 | * not important. | |
1238 | */ | |
1239 | i = n = copy = 0; | |
1240 | do { | |
1241 | start_blknr = blknr = fat_clus_to_blknr(sbi, cluster[i]); | |
1242 | last_blknr = start_blknr + sbi->sec_per_clus; | |
1243 | while (blknr < last_blknr) { | |
1244 | bhs[n] = sb_getblk(sb, blknr); | |
1245 | if (!bhs[n]) { | |
1246 | err = -ENOMEM; | |
1247 | goto error_nomem; | |
1248 | } | |
1249 | ||
1250 | /* fill the directory entry */ | |
1251 | copy = min(size, sb->s_blocksize); | |
07bfa441 OH |
1252 | /* Avoid race with userspace read via bdev */ |
1253 | lock_buffer(bhs[n]); | |
1da177e4 | 1254 | memcpy(bhs[n]->b_data, slots, copy); |
1da177e4 | 1255 | set_buffer_uptodate(bhs[n]); |
07bfa441 | 1256 | unlock_buffer(bhs[n]); |
b522412a | 1257 | mark_buffer_dirty_inode(bhs[n], dir); |
07bfa441 OH |
1258 | slots += copy; |
1259 | size -= copy; | |
1da177e4 LT |
1260 | if (!size) |
1261 | break; | |
1262 | n++; | |
1263 | blknr++; | |
1264 | } | |
1265 | } while (++i < *nr_cluster); | |
1266 | ||
1267 | memset(bhs[n]->b_data + copy, 0, sb->s_blocksize - copy); | |
1268 | offset = copy - sizeof(struct msdos_dir_entry); | |
1269 | get_bh(bhs[n]); | |
1270 | *bh = bhs[n]; | |
1271 | *de = (struct msdos_dir_entry *)((*bh)->b_data + offset); | |
1272 | *i_pos = fat_make_i_pos(sb, *bh, *de); | |
1273 | ||
1274 | /* Second stage: clear the rest of cluster, and write outs */ | |
1275 | err = fat_zeroed_cluster(dir, start_blknr, ++n, bhs, MAX_BUF_PER_PAGE); | |
1276 | if (err) | |
1277 | goto error_free; | |
1278 | ||
1279 | return cluster[0]; | |
1280 | ||
1281 | error_free: | |
1282 | brelse(*bh); | |
1283 | *bh = NULL; | |
1284 | n = 0; | |
1285 | error_nomem: | |
1286 | for (i = 0; i < n; i++) | |
1287 | bforget(bhs[i]); | |
1288 | fat_free_clusters(dir, cluster[0]); | |
1289 | error: | |
1290 | return err; | |
1291 | } | |
1292 | ||
1293 | int fat_add_entries(struct inode *dir, void *slots, int nr_slots, | |
1294 | struct fat_slot_info *sinfo) | |
1295 | { | |
1296 | struct super_block *sb = dir->i_sb; | |
1297 | struct msdos_sb_info *sbi = MSDOS_SB(sb); | |
1298 | struct buffer_head *bh, *prev, *bhs[3]; /* 32*slots (672bytes) */ | |
3f649ab7 | 1299 | struct msdos_dir_entry *de; |
1da177e4 LT |
1300 | int err, free_slots, i, nr_bhs; |
1301 | loff_t pos, i_pos; | |
1302 | ||
1303 | sinfo->nr_slots = nr_slots; | |
1304 | ||
c39540c6 | 1305 | /* First stage: search free directory entries */ |
1da177e4 LT |
1306 | free_slots = nr_bhs = 0; |
1307 | bh = prev = NULL; | |
1308 | pos = 0; | |
1309 | err = -ENOSPC; | |
1310 | while (fat_get_entry(dir, &pos, &bh, &de) > -1) { | |
1311 | /* check the maximum size of directory */ | |
1312 | if (pos >= FAT_MAX_DIR_SIZE) | |
1313 | goto error; | |
1314 | ||
1315 | if (IS_FREE(de->name)) { | |
1316 | if (prev != bh) { | |
1317 | get_bh(bh); | |
1318 | bhs[nr_bhs] = prev = bh; | |
1319 | nr_bhs++; | |
1320 | } | |
1321 | free_slots++; | |
1322 | if (free_slots == nr_slots) | |
1323 | goto found; | |
1324 | } else { | |
1325 | for (i = 0; i < nr_bhs; i++) | |
1326 | brelse(bhs[i]); | |
1327 | prev = NULL; | |
1328 | free_slots = nr_bhs = 0; | |
1329 | } | |
1330 | } | |
1331 | if (dir->i_ino == MSDOS_ROOT_INO) { | |
306790f7 | 1332 | if (!is_fat32(sbi)) |
1da177e4 LT |
1333 | goto error; |
1334 | } else if (MSDOS_I(dir)->i_start == 0) { | |
869f58c0 | 1335 | fat_msg(sb, KERN_ERR, "Corrupted directory (i_pos %lld)", |
1da177e4 LT |
1336 | MSDOS_I(dir)->i_pos); |
1337 | err = -EIO; | |
1338 | goto error; | |
1339 | } | |
1340 | ||
1341 | found: | |
1342 | err = 0; | |
1343 | pos -= free_slots * sizeof(*de); | |
1344 | nr_slots -= free_slots; | |
1345 | if (free_slots) { | |
1346 | /* | |
1347 | * Second stage: filling the free entries with new entries. | |
1348 | * NOTE: If this slots has shortname, first, we write | |
1349 | * the long name slots, then write the short name. | |
1350 | */ | |
1351 | int size = free_slots * sizeof(*de); | |
1352 | int offset = pos & (sb->s_blocksize - 1); | |
1353 | int long_bhs = nr_bhs - (nr_slots == 0); | |
1354 | ||
1355 | /* Fill the long name slots. */ | |
1356 | for (i = 0; i < long_bhs; i++) { | |
1357 | int copy = min_t(int, sb->s_blocksize - offset, size); | |
1358 | memcpy(bhs[i]->b_data + offset, slots, copy); | |
b522412a | 1359 | mark_buffer_dirty_inode(bhs[i], dir); |
1da177e4 LT |
1360 | offset = 0; |
1361 | slots += copy; | |
1362 | size -= copy; | |
1363 | } | |
1364 | if (long_bhs && IS_DIRSYNC(dir)) | |
1365 | err = fat_sync_bhs(bhs, long_bhs); | |
1366 | if (!err && i < nr_bhs) { | |
1367 | /* Fill the short name slot. */ | |
1368 | int copy = min_t(int, sb->s_blocksize - offset, size); | |
1369 | memcpy(bhs[i]->b_data + offset, slots, copy); | |
b522412a | 1370 | mark_buffer_dirty_inode(bhs[i], dir); |
1da177e4 LT |
1371 | if (IS_DIRSYNC(dir)) |
1372 | err = sync_dirty_buffer(bhs[i]); | |
1373 | } | |
1374 | for (i = 0; i < nr_bhs; i++) | |
1375 | brelse(bhs[i]); | |
1376 | if (err) | |
1377 | goto error_remove; | |
1378 | } | |
1379 | ||
1380 | if (nr_slots) { | |
1381 | int cluster, nr_cluster; | |
1382 | ||
1383 | /* | |
1384 | * Third stage: allocate the cluster for new entries. | |
1385 | * And initialize the cluster with new entries, then | |
1386 | * add the cluster to dir. | |
1387 | */ | |
1388 | cluster = fat_add_new_entries(dir, slots, nr_slots, &nr_cluster, | |
1389 | &de, &bh, &i_pos); | |
1390 | if (cluster < 0) { | |
1391 | err = cluster; | |
1392 | goto error_remove; | |
1393 | } | |
1394 | err = fat_chain_add(dir, cluster, nr_cluster); | |
1395 | if (err) { | |
1396 | fat_free_clusters(dir, cluster); | |
1397 | goto error_remove; | |
1398 | } | |
1399 | if (dir->i_size & (sbi->cluster_size - 1)) { | |
85c78591 | 1400 | fat_fs_error(sb, "Odd directory size"); |
1da177e4 LT |
1401 | dir->i_size = (dir->i_size + sbi->cluster_size - 1) |
1402 | & ~((loff_t)sbi->cluster_size - 1); | |
1403 | } | |
1404 | dir->i_size += nr_cluster << sbi->cluster_bits; | |
1405 | MSDOS_I(dir)->mmu_private += nr_cluster << sbi->cluster_bits; | |
1406 | } | |
1407 | sinfo->slot_off = pos; | |
1408 | sinfo->de = de; | |
1409 | sinfo->bh = bh; | |
1410 | sinfo->i_pos = fat_make_i_pos(sb, sinfo->bh, sinfo->de); | |
1411 | ||
1412 | return 0; | |
1413 | ||
1414 | error: | |
1415 | brelse(bh); | |
1416 | for (i = 0; i < nr_bhs; i++) | |
1417 | brelse(bhs[i]); | |
1418 | return err; | |
1419 | ||
1420 | error_remove: | |
1421 | brelse(bh); | |
1422 | if (free_slots) | |
1423 | __fat_remove_entries(dir, pos, free_slots); | |
1424 | return err; | |
1425 | } | |
7c709d00 | 1426 | EXPORT_SYMBOL_GPL(fat_add_entries); |