1
2
3
4
5
6#include <linux/slab.h>
7#include <linux/compat.h>
8#include <linux/bio.h>
9#include <linux/buffer_head.h>
10
11#include "exfat_raw.h"
12#include "exfat_fs.h"
13
14static int exfat_extract_uni_name(struct exfat_dentry *ep,
15 unsigned short *uniname)
16{
17 int i, len = 0;
18
19 for (i = 0; i < EXFAT_FILE_NAME_LEN; i++) {
20 *uniname = le16_to_cpu(ep->dentry.name.unicode_0_14[i]);
21 if (*uniname == 0x0)
22 return len;
23 uniname++;
24 len++;
25 }
26
27 *uniname = 0x0;
28 return len;
29
30}
31
32static void exfat_get_uniname_from_ext_entry(struct super_block *sb,
33 struct exfat_chain *p_dir, int entry, unsigned short *uniname)
34{
35 int i;
36 struct exfat_entry_set_cache *es;
37
38 es = exfat_get_dentry_set(sb, p_dir, entry, ES_ALL_ENTRIES);
39 if (!es)
40 return;
41
42
43
44
45
46
47
48 for (i = 2; i < es->num_entries; i++) {
49 struct exfat_dentry *ep = exfat_get_dentry_cached(es, i);
50
51
52 if (exfat_get_entry_type(ep) != TYPE_EXTEND)
53 break;
54
55 exfat_extract_uni_name(ep, uniname);
56 uniname += EXFAT_FILE_NAME_LEN;
57 }
58
59 exfat_free_dentry_set(es, false);
60}
61
62
63static int exfat_readdir(struct inode *inode, loff_t *cpos, struct exfat_dir_entry *dir_entry)
64{
65 int i, dentries_per_clu, dentries_per_clu_bits = 0, num_ext;
66 unsigned int type, clu_offset, max_dentries;
67 struct exfat_chain dir, clu;
68 struct exfat_uni_name uni_name;
69 struct exfat_dentry *ep;
70 struct super_block *sb = inode->i_sb;
71 struct exfat_sb_info *sbi = EXFAT_SB(sb);
72 struct exfat_inode_info *ei = EXFAT_I(inode);
73 unsigned int dentry = EXFAT_B_TO_DEN(*cpos) & 0xFFFFFFFF;
74 struct buffer_head *bh;
75
76
77 if (ei->type != TYPE_DIR)
78 return -EPERM;
79
80 if (ei->entry == -1)
81 exfat_chain_set(&dir, sbi->root_dir, 0, ALLOC_FAT_CHAIN);
82 else
83 exfat_chain_set(&dir, ei->start_clu,
84 EXFAT_B_TO_CLU(i_size_read(inode), sbi), ei->flags);
85
86 dentries_per_clu = sbi->dentries_per_clu;
87 dentries_per_clu_bits = ilog2(dentries_per_clu);
88 max_dentries = (unsigned int)min_t(u64, MAX_EXFAT_DENTRIES,
89 (u64)sbi->num_clusters << dentries_per_clu_bits);
90
91 clu_offset = dentry >> dentries_per_clu_bits;
92 exfat_chain_dup(&clu, &dir);
93
94 if (clu.flags == ALLOC_NO_FAT_CHAIN) {
95 clu.dir += clu_offset;
96 clu.size -= clu_offset;
97 } else {
98
99 if (clu_offset > 0 && ei->hint_bmap.off != EXFAT_EOF_CLUSTER &&
100 ei->hint_bmap.off > 0 && clu_offset >= ei->hint_bmap.off) {
101 clu_offset -= ei->hint_bmap.off;
102 clu.dir = ei->hint_bmap.clu;
103 }
104
105 while (clu_offset > 0) {
106 if (exfat_get_next_cluster(sb, &(clu.dir)))
107 return -EIO;
108
109 clu_offset--;
110 }
111 }
112
113 while (clu.dir != EXFAT_EOF_CLUSTER && dentry < max_dentries) {
114 i = dentry & (dentries_per_clu - 1);
115
116 for ( ; i < dentries_per_clu; i++, dentry++) {
117 ep = exfat_get_dentry(sb, &clu, i, &bh);
118 if (!ep)
119 return -EIO;
120
121 type = exfat_get_entry_type(ep);
122 if (type == TYPE_UNUSED) {
123 brelse(bh);
124 break;
125 }
126
127 if (type != TYPE_FILE && type != TYPE_DIR) {
128 brelse(bh);
129 continue;
130 }
131
132 num_ext = ep->dentry.file.num_ext;
133 dir_entry->attr = le16_to_cpu(ep->dentry.file.attr);
134 exfat_get_entry_time(sbi, &dir_entry->crtime,
135 ep->dentry.file.create_tz,
136 ep->dentry.file.create_time,
137 ep->dentry.file.create_date,
138 ep->dentry.file.create_time_cs);
139 exfat_get_entry_time(sbi, &dir_entry->mtime,
140 ep->dentry.file.modify_tz,
141 ep->dentry.file.modify_time,
142 ep->dentry.file.modify_date,
143 ep->dentry.file.modify_time_cs);
144 exfat_get_entry_time(sbi, &dir_entry->atime,
145 ep->dentry.file.access_tz,
146 ep->dentry.file.access_time,
147 ep->dentry.file.access_date,
148 0);
149
150 *uni_name.name = 0x0;
151 exfat_get_uniname_from_ext_entry(sb, &clu, i,
152 uni_name.name);
153 exfat_utf16_to_nls(sb, &uni_name,
154 dir_entry->namebuf.lfn,
155 dir_entry->namebuf.lfnbuf_len);
156 brelse(bh);
157
158 ep = exfat_get_dentry(sb, &clu, i + 1, &bh);
159 if (!ep)
160 return -EIO;
161 dir_entry->size =
162 le64_to_cpu(ep->dentry.stream.valid_size);
163 dir_entry->entry = dentry;
164 brelse(bh);
165
166 ei->hint_bmap.off = dentry >> dentries_per_clu_bits;
167 ei->hint_bmap.clu = clu.dir;
168
169 *cpos = EXFAT_DEN_TO_B(dentry + 1 + num_ext);
170 return 0;
171 }
172
173 if (clu.flags == ALLOC_NO_FAT_CHAIN) {
174 if (--clu.size > 0)
175 clu.dir++;
176 else
177 clu.dir = EXFAT_EOF_CLUSTER;
178 } else {
179 if (exfat_get_next_cluster(sb, &(clu.dir)))
180 return -EIO;
181 }
182 }
183
184 dir_entry->namebuf.lfn[0] = '\0';
185 *cpos = EXFAT_DEN_TO_B(dentry);
186 return 0;
187}
188
189static void exfat_init_namebuf(struct exfat_dentry_namebuf *nb)
190{
191 nb->lfn = NULL;
192 nb->lfnbuf_len = 0;
193}
194
195static int exfat_alloc_namebuf(struct exfat_dentry_namebuf *nb)
196{
197 nb->lfn = __getname();
198 if (!nb->lfn)
199 return -ENOMEM;
200 nb->lfnbuf_len = MAX_VFSNAME_BUF_SIZE;
201 return 0;
202}
203
204static void exfat_free_namebuf(struct exfat_dentry_namebuf *nb)
205{
206 if (!nb->lfn)
207 return;
208
209 __putname(nb->lfn);
210 exfat_init_namebuf(nb);
211}
212
213
214#define ITER_POS_FILLED_DOTS (2)
215static int exfat_iterate(struct file *filp, struct dir_context *ctx)
216{
217 struct inode *inode = filp->f_path.dentry->d_inode;
218 struct super_block *sb = inode->i_sb;
219 struct inode *tmp;
220 struct exfat_dir_entry de;
221 struct exfat_dentry_namebuf *nb = &(de.namebuf);
222 struct exfat_inode_info *ei = EXFAT_I(inode);
223 unsigned long inum;
224 loff_t cpos, i_pos;
225 int err = 0, fake_offset = 0;
226
227 exfat_init_namebuf(nb);
228 mutex_lock(&EXFAT_SB(sb)->s_lock);
229
230 cpos = ctx->pos;
231 if (!dir_emit_dots(filp, ctx))
232 goto unlock;
233
234 if (ctx->pos == ITER_POS_FILLED_DOTS) {
235 cpos = 0;
236 fake_offset = 1;
237 }
238
239 if (cpos & (DENTRY_SIZE - 1)) {
240 err = -ENOENT;
241 goto unlock;
242 }
243
244
245 err = exfat_alloc_namebuf(nb);
246 if (err)
247 goto unlock;
248get_new:
249 if (ei->flags == ALLOC_NO_FAT_CHAIN && cpos >= i_size_read(inode))
250 goto end_of_dir;
251
252 err = exfat_readdir(inode, &cpos, &de);
253 if (err) {
254
255
256
257
258 if (err == -EIO) {
259 cpos += 1 << (sb->s_blocksize_bits);
260 cpos &= ~(sb->s_blocksize - 1);
261 }
262
263 err = -EIO;
264 goto end_of_dir;
265 }
266
267 if (!nb->lfn[0])
268 goto end_of_dir;
269
270 i_pos = ((loff_t)ei->start_clu << 32) | (de.entry & 0xffffffff);
271 tmp = exfat_iget(sb, i_pos);
272 if (tmp) {
273 inum = tmp->i_ino;
274 iput(tmp);
275 } else {
276 inum = iunique(sb, EXFAT_ROOT_INO);
277 }
278
279
280
281
282
283
284 mutex_unlock(&EXFAT_SB(sb)->s_lock);
285 if (!dir_emit(ctx, nb->lfn, strlen(nb->lfn), inum,
286 (de.attr & ATTR_SUBDIR) ? DT_DIR : DT_REG))
287 goto out_unlocked;
288 mutex_lock(&EXFAT_SB(sb)->s_lock);
289 ctx->pos = cpos;
290 goto get_new;
291
292end_of_dir:
293 if (!cpos && fake_offset)
294 cpos = ITER_POS_FILLED_DOTS;
295 ctx->pos = cpos;
296unlock:
297 mutex_unlock(&EXFAT_SB(sb)->s_lock);
298out_unlocked:
299
300
301
302
303 exfat_free_namebuf(nb);
304 return err;
305}
306
307const struct file_operations exfat_dir_operations = {
308 .llseek = generic_file_llseek,
309 .read = generic_read_dir,
310 .iterate = exfat_iterate,
311 .unlocked_ioctl = exfat_ioctl,
312#ifdef CONFIG_COMPAT
313 .compat_ioctl = exfat_compat_ioctl,
314#endif
315 .fsync = exfat_file_fsync,
316};
317
318int exfat_alloc_new_dir(struct inode *inode, struct exfat_chain *clu)
319{
320 int ret;
321
322 exfat_chain_set(clu, EXFAT_EOF_CLUSTER, 0, ALLOC_NO_FAT_CHAIN);
323
324 ret = exfat_alloc_cluster(inode, 1, clu, IS_DIRSYNC(inode));
325 if (ret)
326 return ret;
327
328 return exfat_zeroed_cluster(inode, clu->dir);
329}
330
331int exfat_calc_num_entries(struct exfat_uni_name *p_uniname)
332{
333 int len;
334
335 len = p_uniname->name_len;
336 if (len == 0)
337 return -EINVAL;
338
339
340 return ((len - 1) / EXFAT_FILE_NAME_LEN + 3);
341}
342
343unsigned int exfat_get_entry_type(struct exfat_dentry *ep)
344{
345 if (ep->type == EXFAT_UNUSED)
346 return TYPE_UNUSED;
347 if (IS_EXFAT_DELETED(ep->type))
348 return TYPE_DELETED;
349 if (ep->type == EXFAT_INVAL)
350 return TYPE_INVALID;
351 if (IS_EXFAT_CRITICAL_PRI(ep->type)) {
352 if (ep->type == EXFAT_BITMAP)
353 return TYPE_BITMAP;
354 if (ep->type == EXFAT_UPCASE)
355 return TYPE_UPCASE;
356 if (ep->type == EXFAT_VOLUME)
357 return TYPE_VOLUME;
358 if (ep->type == EXFAT_FILE) {
359 if (le16_to_cpu(ep->dentry.file.attr) & ATTR_SUBDIR)
360 return TYPE_DIR;
361 return TYPE_FILE;
362 }
363 return TYPE_CRITICAL_PRI;
364 }
365 if (IS_EXFAT_BENIGN_PRI(ep->type)) {
366 if (ep->type == EXFAT_GUID)
367 return TYPE_GUID;
368 if (ep->type == EXFAT_PADDING)
369 return TYPE_PADDING;
370 if (ep->type == EXFAT_ACLTAB)
371 return TYPE_ACLTAB;
372 return TYPE_BENIGN_PRI;
373 }
374 if (IS_EXFAT_CRITICAL_SEC(ep->type)) {
375 if (ep->type == EXFAT_STREAM)
376 return TYPE_STREAM;
377 if (ep->type == EXFAT_NAME)
378 return TYPE_EXTEND;
379 if (ep->type == EXFAT_ACL)
380 return TYPE_ACL;
381 return TYPE_CRITICAL_SEC;
382 }
383 return TYPE_BENIGN_SEC;
384}
385
386static void exfat_set_entry_type(struct exfat_dentry *ep, unsigned int type)
387{
388 if (type == TYPE_UNUSED) {
389 ep->type = EXFAT_UNUSED;
390 } else if (type == TYPE_DELETED) {
391 ep->type &= EXFAT_DELETE;
392 } else if (type == TYPE_STREAM) {
393 ep->type = EXFAT_STREAM;
394 } else if (type == TYPE_EXTEND) {
395 ep->type = EXFAT_NAME;
396 } else if (type == TYPE_BITMAP) {
397 ep->type = EXFAT_BITMAP;
398 } else if (type == TYPE_UPCASE) {
399 ep->type = EXFAT_UPCASE;
400 } else if (type == TYPE_VOLUME) {
401 ep->type = EXFAT_VOLUME;
402 } else if (type == TYPE_DIR) {
403 ep->type = EXFAT_FILE;
404 ep->dentry.file.attr = cpu_to_le16(ATTR_SUBDIR);
405 } else if (type == TYPE_FILE) {
406 ep->type = EXFAT_FILE;
407 ep->dentry.file.attr = cpu_to_le16(ATTR_ARCHIVE);
408 }
409}
410
411static void exfat_init_stream_entry(struct exfat_dentry *ep,
412 unsigned char flags, unsigned int start_clu,
413 unsigned long long size)
414{
415 exfat_set_entry_type(ep, TYPE_STREAM);
416 ep->dentry.stream.flags = flags;
417 ep->dentry.stream.start_clu = cpu_to_le32(start_clu);
418 ep->dentry.stream.valid_size = cpu_to_le64(size);
419 ep->dentry.stream.size = cpu_to_le64(size);
420}
421
422static void exfat_init_name_entry(struct exfat_dentry *ep,
423 unsigned short *uniname)
424{
425 int i;
426
427 exfat_set_entry_type(ep, TYPE_EXTEND);
428 ep->dentry.name.flags = 0x0;
429
430 for (i = 0; i < EXFAT_FILE_NAME_LEN; i++) {
431 if (*uniname != 0x0) {
432 ep->dentry.name.unicode_0_14[i] = cpu_to_le16(*uniname);
433 uniname++;
434 } else {
435 ep->dentry.name.unicode_0_14[i] = 0x0;
436 }
437 }
438}
439
440int exfat_init_dir_entry(struct inode *inode, struct exfat_chain *p_dir,
441 int entry, unsigned int type, unsigned int start_clu,
442 unsigned long long size)
443{
444 struct super_block *sb = inode->i_sb;
445 struct exfat_sb_info *sbi = EXFAT_SB(sb);
446 struct timespec64 ts = current_time(inode);
447 struct exfat_dentry *ep;
448 struct buffer_head *bh;
449
450
451
452
453
454 ep = exfat_get_dentry(sb, p_dir, entry, &bh);
455 if (!ep)
456 return -EIO;
457
458 exfat_set_entry_type(ep, type);
459 exfat_set_entry_time(sbi, &ts,
460 &ep->dentry.file.create_tz,
461 &ep->dentry.file.create_time,
462 &ep->dentry.file.create_date,
463 &ep->dentry.file.create_time_cs);
464 exfat_set_entry_time(sbi, &ts,
465 &ep->dentry.file.modify_tz,
466 &ep->dentry.file.modify_time,
467 &ep->dentry.file.modify_date,
468 &ep->dentry.file.modify_time_cs);
469 exfat_set_entry_time(sbi, &ts,
470 &ep->dentry.file.access_tz,
471 &ep->dentry.file.access_time,
472 &ep->dentry.file.access_date,
473 NULL);
474
475 exfat_update_bh(bh, IS_DIRSYNC(inode));
476 brelse(bh);
477
478 ep = exfat_get_dentry(sb, p_dir, entry + 1, &bh);
479 if (!ep)
480 return -EIO;
481
482 exfat_init_stream_entry(ep,
483 (type == TYPE_FILE) ? ALLOC_FAT_CHAIN : ALLOC_NO_FAT_CHAIN,
484 start_clu, size);
485 exfat_update_bh(bh, IS_DIRSYNC(inode));
486 brelse(bh);
487
488 return 0;
489}
490
491int exfat_update_dir_chksum(struct inode *inode, struct exfat_chain *p_dir,
492 int entry)
493{
494 struct super_block *sb = inode->i_sb;
495 int ret = 0;
496 int i, num_entries;
497 u16 chksum;
498 struct exfat_dentry *ep, *fep;
499 struct buffer_head *fbh, *bh;
500
501 fep = exfat_get_dentry(sb, p_dir, entry, &fbh);
502 if (!fep)
503 return -EIO;
504
505 num_entries = fep->dentry.file.num_ext + 1;
506 chksum = exfat_calc_chksum16(fep, DENTRY_SIZE, 0, CS_DIR_ENTRY);
507
508 for (i = 1; i < num_entries; i++) {
509 ep = exfat_get_dentry(sb, p_dir, entry + i, &bh);
510 if (!ep) {
511 ret = -EIO;
512 goto release_fbh;
513 }
514 chksum = exfat_calc_chksum16(ep, DENTRY_SIZE, chksum,
515 CS_DEFAULT);
516 brelse(bh);
517 }
518
519 fep->dentry.file.checksum = cpu_to_le16(chksum);
520 exfat_update_bh(fbh, IS_DIRSYNC(inode));
521release_fbh:
522 brelse(fbh);
523 return ret;
524}
525
526int exfat_init_ext_entry(struct inode *inode, struct exfat_chain *p_dir,
527 int entry, int num_entries, struct exfat_uni_name *p_uniname)
528{
529 struct super_block *sb = inode->i_sb;
530 int i;
531 unsigned short *uniname = p_uniname->name;
532 struct exfat_dentry *ep;
533 struct buffer_head *bh;
534 int sync = IS_DIRSYNC(inode);
535
536 ep = exfat_get_dentry(sb, p_dir, entry, &bh);
537 if (!ep)
538 return -EIO;
539
540 ep->dentry.file.num_ext = (unsigned char)(num_entries - 1);
541 exfat_update_bh(bh, sync);
542 brelse(bh);
543
544 ep = exfat_get_dentry(sb, p_dir, entry + 1, &bh);
545 if (!ep)
546 return -EIO;
547
548 ep->dentry.stream.name_len = p_uniname->name_len;
549 ep->dentry.stream.name_hash = cpu_to_le16(p_uniname->name_hash);
550 exfat_update_bh(bh, sync);
551 brelse(bh);
552
553 for (i = EXFAT_FIRST_CLUSTER; i < num_entries; i++) {
554 ep = exfat_get_dentry(sb, p_dir, entry + i, &bh);
555 if (!ep)
556 return -EIO;
557
558 exfat_init_name_entry(ep, uniname);
559 exfat_update_bh(bh, sync);
560 brelse(bh);
561 uniname += EXFAT_FILE_NAME_LEN;
562 }
563
564 exfat_update_dir_chksum(inode, p_dir, entry);
565 return 0;
566}
567
568int exfat_remove_entries(struct inode *inode, struct exfat_chain *p_dir,
569 int entry, int order, int num_entries)
570{
571 struct super_block *sb = inode->i_sb;
572 int i;
573 struct exfat_dentry *ep;
574 struct buffer_head *bh;
575
576 for (i = order; i < num_entries; i++) {
577 ep = exfat_get_dentry(sb, p_dir, entry + i, &bh);
578 if (!ep)
579 return -EIO;
580
581 exfat_set_entry_type(ep, TYPE_DELETED);
582 exfat_update_bh(bh, IS_DIRSYNC(inode));
583 brelse(bh);
584 }
585
586 return 0;
587}
588
589void exfat_update_dir_chksum_with_entry_set(struct exfat_entry_set_cache *es)
590{
591 int chksum_type = CS_DIR_ENTRY, i;
592 unsigned short chksum = 0;
593 struct exfat_dentry *ep;
594
595 for (i = 0; i < es->num_entries; i++) {
596 ep = exfat_get_dentry_cached(es, i);
597 chksum = exfat_calc_chksum16(ep, DENTRY_SIZE, chksum,
598 chksum_type);
599 chksum_type = CS_DEFAULT;
600 }
601 ep = exfat_get_dentry_cached(es, 0);
602 ep->dentry.file.checksum = cpu_to_le16(chksum);
603 es->modified = true;
604}
605
606int exfat_free_dentry_set(struct exfat_entry_set_cache *es, int sync)
607{
608 int i, err = 0;
609
610 if (es->modified)
611 err = exfat_update_bhs(es->bh, es->num_bh, sync);
612
613 for (i = 0; i < es->num_bh; i++)
614 if (err)
615 bforget(es->bh[i]);
616 else
617 brelse(es->bh[i]);
618 kfree(es);
619 return err;
620}
621
622static int exfat_walk_fat_chain(struct super_block *sb,
623 struct exfat_chain *p_dir, unsigned int byte_offset,
624 unsigned int *clu)
625{
626 struct exfat_sb_info *sbi = EXFAT_SB(sb);
627 unsigned int clu_offset;
628 unsigned int cur_clu;
629
630 clu_offset = EXFAT_B_TO_CLU(byte_offset, sbi);
631 cur_clu = p_dir->dir;
632
633 if (p_dir->flags == ALLOC_NO_FAT_CHAIN) {
634 cur_clu += clu_offset;
635 } else {
636 while (clu_offset > 0) {
637 if (exfat_get_next_cluster(sb, &cur_clu))
638 return -EIO;
639 if (cur_clu == EXFAT_EOF_CLUSTER) {
640 exfat_fs_error(sb,
641 "invalid dentry access beyond EOF (clu : %u, eidx : %d)",
642 p_dir->dir,
643 EXFAT_B_TO_DEN(byte_offset));
644 return -EIO;
645 }
646 clu_offset--;
647 }
648 }
649
650 *clu = cur_clu;
651 return 0;
652}
653
654static int exfat_find_location(struct super_block *sb, struct exfat_chain *p_dir,
655 int entry, sector_t *sector, int *offset)
656{
657 int ret;
658 unsigned int off, clu = 0;
659 struct exfat_sb_info *sbi = EXFAT_SB(sb);
660
661 off = EXFAT_DEN_TO_B(entry);
662
663 ret = exfat_walk_fat_chain(sb, p_dir, off, &clu);
664 if (ret)
665 return ret;
666
667
668 off = EXFAT_CLU_OFFSET(off, sbi);
669
670
671 *offset = EXFAT_BLK_OFFSET(off, sb);
672
673
674 *sector = EXFAT_B_TO_BLK(off, sb);
675 *sector += exfat_cluster_to_sector(sbi, clu);
676 return 0;
677}
678
679#define EXFAT_MAX_RA_SIZE (128*1024)
680static int exfat_dir_readahead(struct super_block *sb, sector_t sec)
681{
682 struct exfat_sb_info *sbi = EXFAT_SB(sb);
683 struct buffer_head *bh;
684 unsigned int max_ra_count = EXFAT_MAX_RA_SIZE >> sb->s_blocksize_bits;
685 unsigned int page_ra_count = PAGE_SIZE >> sb->s_blocksize_bits;
686 unsigned int adj_ra_count = max(sbi->sect_per_clus, page_ra_count);
687 unsigned int ra_count = min(adj_ra_count, max_ra_count);
688
689
690 if (sbi->sect_per_clus == 1)
691 return 0;
692
693 if (sec < sbi->data_start_sector) {
694 exfat_err(sb, "requested sector is invalid(sect:%llu, root:%llu)",
695 (unsigned long long)sec, sbi->data_start_sector);
696 return -EIO;
697 }
698
699
700 if ((sec - sbi->data_start_sector) & (ra_count - 1))
701 ra_count = page_ra_count;
702
703 bh = sb_find_get_block(sb, sec);
704 if (!bh || !buffer_uptodate(bh)) {
705 unsigned int i;
706
707 for (i = 0; i < ra_count; i++)
708 sb_breadahead(sb, (sector_t)(sec + i));
709 }
710 brelse(bh);
711 return 0;
712}
713
714struct exfat_dentry *exfat_get_dentry(struct super_block *sb,
715 struct exfat_chain *p_dir, int entry, struct buffer_head **bh)
716{
717 unsigned int dentries_per_page = EXFAT_B_TO_DEN(PAGE_SIZE);
718 int off;
719 sector_t sec;
720
721 if (p_dir->dir == DIR_DELETED) {
722 exfat_err(sb, "abnormal access to deleted dentry");
723 return NULL;
724 }
725
726 if (exfat_find_location(sb, p_dir, entry, &sec, &off))
727 return NULL;
728
729 if (p_dir->dir != EXFAT_FREE_CLUSTER &&
730 !(entry & (dentries_per_page - 1)))
731 exfat_dir_readahead(sb, sec);
732
733 *bh = sb_bread(sb, sec);
734 if (!*bh)
735 return NULL;
736
737 return (struct exfat_dentry *)((*bh)->b_data + off);
738}
739
740enum exfat_validate_dentry_mode {
741 ES_MODE_STARTED,
742 ES_MODE_GET_FILE_ENTRY,
743 ES_MODE_GET_STRM_ENTRY,
744 ES_MODE_GET_NAME_ENTRY,
745 ES_MODE_GET_CRITICAL_SEC_ENTRY,
746};
747
748static bool exfat_validate_entry(unsigned int type,
749 enum exfat_validate_dentry_mode *mode)
750{
751 if (type == TYPE_UNUSED || type == TYPE_DELETED)
752 return false;
753
754 switch (*mode) {
755 case ES_MODE_STARTED:
756 if (type != TYPE_FILE && type != TYPE_DIR)
757 return false;
758 *mode = ES_MODE_GET_FILE_ENTRY;
759 return true;
760 case ES_MODE_GET_FILE_ENTRY:
761 if (type != TYPE_STREAM)
762 return false;
763 *mode = ES_MODE_GET_STRM_ENTRY;
764 return true;
765 case ES_MODE_GET_STRM_ENTRY:
766 if (type != TYPE_EXTEND)
767 return false;
768 *mode = ES_MODE_GET_NAME_ENTRY;
769 return true;
770 case ES_MODE_GET_NAME_ENTRY:
771 if (type == TYPE_STREAM)
772 return false;
773 if (type != TYPE_EXTEND) {
774 if (!(type & TYPE_CRITICAL_SEC))
775 return false;
776 *mode = ES_MODE_GET_CRITICAL_SEC_ENTRY;
777 }
778 return true;
779 case ES_MODE_GET_CRITICAL_SEC_ENTRY:
780 if (type == TYPE_EXTEND || type == TYPE_STREAM)
781 return false;
782 if ((type & TYPE_CRITICAL_SEC) != TYPE_CRITICAL_SEC)
783 return false;
784 return true;
785 default:
786 WARN_ON_ONCE(1);
787 return false;
788 }
789}
790
791struct exfat_dentry *exfat_get_dentry_cached(
792 struct exfat_entry_set_cache *es, int num)
793{
794 int off = es->start_off + num * DENTRY_SIZE;
795 struct buffer_head *bh = es->bh[EXFAT_B_TO_BLK(off, es->sb)];
796 char *p = bh->b_data + EXFAT_BLK_OFFSET(off, es->sb);
797
798 return (struct exfat_dentry *)p;
799}
800
801
802
803
804
805
806
807
808
809
810
811
812
813
814
815struct exfat_entry_set_cache *exfat_get_dentry_set(struct super_block *sb,
816 struct exfat_chain *p_dir, int entry, unsigned int type)
817{
818 int ret, i, num_bh;
819 unsigned int off, byte_offset, clu = 0;
820 sector_t sec;
821 struct exfat_sb_info *sbi = EXFAT_SB(sb);
822 struct exfat_entry_set_cache *es;
823 struct exfat_dentry *ep;
824 int num_entries;
825 enum exfat_validate_dentry_mode mode = ES_MODE_STARTED;
826 struct buffer_head *bh;
827
828 if (p_dir->dir == DIR_DELETED) {
829 exfat_err(sb, "access to deleted dentry");
830 return NULL;
831 }
832
833 byte_offset = EXFAT_DEN_TO_B(entry);
834 ret = exfat_walk_fat_chain(sb, p_dir, byte_offset, &clu);
835 if (ret)
836 return NULL;
837
838 es = kzalloc(sizeof(*es), GFP_KERNEL);
839 if (!es)
840 return NULL;
841 es->sb = sb;
842 es->modified = false;
843
844
845 byte_offset = EXFAT_CLU_OFFSET(byte_offset, sbi);
846
847
848 off = EXFAT_BLK_OFFSET(byte_offset, sb);
849 es->start_off = off;
850
851
852 sec = EXFAT_B_TO_BLK(byte_offset, sb);
853 sec += exfat_cluster_to_sector(sbi, clu);
854
855 bh = sb_bread(sb, sec);
856 if (!bh)
857 goto free_es;
858 es->bh[es->num_bh++] = bh;
859
860 ep = exfat_get_dentry_cached(es, 0);
861 if (!exfat_validate_entry(exfat_get_entry_type(ep), &mode))
862 goto free_es;
863
864 num_entries = type == ES_ALL_ENTRIES ?
865 ep->dentry.file.num_ext + 1 : type;
866 es->num_entries = num_entries;
867
868 num_bh = EXFAT_B_TO_BLK_ROUND_UP(off + num_entries * DENTRY_SIZE, sb);
869 for (i = 1; i < num_bh; i++) {
870
871 if (exfat_is_last_sector_in_cluster(sbi, sec)) {
872 if (p_dir->flags == ALLOC_NO_FAT_CHAIN)
873 clu++;
874 else if (exfat_get_next_cluster(sb, &clu))
875 goto free_es;
876 sec = exfat_cluster_to_sector(sbi, clu);
877 } else {
878 sec++;
879 }
880
881 bh = sb_bread(sb, sec);
882 if (!bh)
883 goto free_es;
884 es->bh[es->num_bh++] = bh;
885 }
886
887
888 for (i = 1; i < num_entries; i++) {
889 ep = exfat_get_dentry_cached(es, i);
890 if (!exfat_validate_entry(exfat_get_entry_type(ep), &mode))
891 goto free_es;
892 }
893 return es;
894
895free_es:
896 exfat_free_dentry_set(es, false);
897 return NULL;
898}
899
900enum {
901 DIRENT_STEP_FILE,
902 DIRENT_STEP_STRM,
903 DIRENT_STEP_NAME,
904 DIRENT_STEP_SECD,
905};
906
907
908
909
910
911
912
913
914
915
916
917
918int exfat_find_dir_entry(struct super_block *sb, struct exfat_inode_info *ei,
919 struct exfat_chain *p_dir, struct exfat_uni_name *p_uniname,
920 int num_entries, unsigned int type, struct exfat_hint *hint_opt)
921{
922 int i, rewind = 0, dentry = 0, end_eidx = 0, num_ext = 0, len;
923 int order, step, name_len = 0;
924 int dentries_per_clu, num_empty = 0;
925 unsigned int entry_type;
926 unsigned short *uniname = NULL;
927 struct exfat_chain clu;
928 struct exfat_hint *hint_stat = &ei->hint_stat;
929 struct exfat_hint_femp candi_empty;
930 struct exfat_sb_info *sbi = EXFAT_SB(sb);
931
932 dentries_per_clu = sbi->dentries_per_clu;
933
934 exfat_chain_dup(&clu, p_dir);
935
936 if (hint_stat->eidx) {
937 clu.dir = hint_stat->clu;
938 dentry = hint_stat->eidx;
939 end_eidx = dentry;
940 }
941
942 candi_empty.eidx = EXFAT_HINT_NONE;
943rewind:
944 order = 0;
945 step = DIRENT_STEP_FILE;
946 while (clu.dir != EXFAT_EOF_CLUSTER) {
947 i = dentry & (dentries_per_clu - 1);
948 for (; i < dentries_per_clu; i++, dentry++) {
949 struct exfat_dentry *ep;
950 struct buffer_head *bh;
951
952 if (rewind && dentry == end_eidx)
953 goto not_found;
954
955 ep = exfat_get_dentry(sb, &clu, i, &bh);
956 if (!ep)
957 return -EIO;
958
959 entry_type = exfat_get_entry_type(ep);
960
961 if (entry_type == TYPE_UNUSED ||
962 entry_type == TYPE_DELETED) {
963 step = DIRENT_STEP_FILE;
964
965 num_empty++;
966 if (candi_empty.eidx == EXFAT_HINT_NONE &&
967 num_empty == 1) {
968 exfat_chain_set(&candi_empty.cur,
969 clu.dir, clu.size, clu.flags);
970 }
971
972 if (candi_empty.eidx == EXFAT_HINT_NONE &&
973 num_empty >= num_entries) {
974 candi_empty.eidx =
975 dentry - (num_empty - 1);
976 WARN_ON(candi_empty.eidx < 0);
977 candi_empty.count = num_empty;
978
979 if (ei->hint_femp.eidx ==
980 EXFAT_HINT_NONE ||
981 candi_empty.eidx <=
982 ei->hint_femp.eidx)
983 ei->hint_femp = candi_empty;
984 }
985
986 brelse(bh);
987 if (entry_type == TYPE_UNUSED)
988 goto not_found;
989 continue;
990 }
991
992 num_empty = 0;
993 candi_empty.eidx = EXFAT_HINT_NONE;
994
995 if (entry_type == TYPE_FILE || entry_type == TYPE_DIR) {
996 step = DIRENT_STEP_FILE;
997 hint_opt->clu = clu.dir;
998 hint_opt->eidx = i;
999 if (type == TYPE_ALL || type == entry_type) {
1000 num_ext = ep->dentry.file.num_ext;
1001 step = DIRENT_STEP_STRM;
1002 }
1003 brelse(bh);
1004 continue;
1005 }
1006
1007 if (entry_type == TYPE_STREAM) {
1008 u16 name_hash;
1009
1010 if (step != DIRENT_STEP_STRM) {
1011 step = DIRENT_STEP_FILE;
1012 brelse(bh);
1013 continue;
1014 }
1015 step = DIRENT_STEP_FILE;
1016 name_hash = le16_to_cpu(
1017 ep->dentry.stream.name_hash);
1018 if (p_uniname->name_hash == name_hash &&
1019 p_uniname->name_len ==
1020 ep->dentry.stream.name_len) {
1021 step = DIRENT_STEP_NAME;
1022 order = 1;
1023 name_len = 0;
1024 }
1025 brelse(bh);
1026 continue;
1027 }
1028
1029 brelse(bh);
1030 if (entry_type == TYPE_EXTEND) {
1031 unsigned short entry_uniname[16], unichar;
1032
1033 if (step != DIRENT_STEP_NAME) {
1034 step = DIRENT_STEP_FILE;
1035 continue;
1036 }
1037
1038 if (++order == 2)
1039 uniname = p_uniname->name;
1040 else
1041 uniname += EXFAT_FILE_NAME_LEN;
1042
1043 len = exfat_extract_uni_name(ep, entry_uniname);
1044 name_len += len;
1045
1046 unichar = *(uniname+len);
1047 *(uniname+len) = 0x0;
1048
1049 if (exfat_uniname_ncmp(sb, uniname,
1050 entry_uniname, len)) {
1051 step = DIRENT_STEP_FILE;
1052 } else if (p_uniname->name_len == name_len) {
1053 if (order == num_ext)
1054 goto found;
1055 step = DIRENT_STEP_SECD;
1056 }
1057
1058 *(uniname+len) = unichar;
1059 continue;
1060 }
1061
1062 if (entry_type &
1063 (TYPE_CRITICAL_SEC | TYPE_BENIGN_SEC)) {
1064 if (step == DIRENT_STEP_SECD) {
1065 if (++order == num_ext)
1066 goto found;
1067 continue;
1068 }
1069 }
1070 step = DIRENT_STEP_FILE;
1071 }
1072
1073 if (clu.flags == ALLOC_NO_FAT_CHAIN) {
1074 if (--clu.size > 0)
1075 clu.dir++;
1076 else
1077 clu.dir = EXFAT_EOF_CLUSTER;
1078 } else {
1079 if (exfat_get_next_cluster(sb, &clu.dir))
1080 return -EIO;
1081 }
1082 }
1083
1084not_found:
1085
1086
1087
1088
1089 if (!rewind && end_eidx) {
1090 rewind = 1;
1091 dentry = 0;
1092 clu.dir = p_dir->dir;
1093
1094 num_empty = 0;
1095 candi_empty.eidx = EXFAT_HINT_NONE;
1096 goto rewind;
1097 }
1098
1099
1100 hint_stat->clu = p_dir->dir;
1101 hint_stat->eidx = 0;
1102 return -ENOENT;
1103
1104found:
1105
1106 if (!((dentry + 1) & (dentries_per_clu - 1))) {
1107 int ret = 0;
1108
1109 if (clu.flags == ALLOC_NO_FAT_CHAIN) {
1110 if (--clu.size > 0)
1111 clu.dir++;
1112 else
1113 clu.dir = EXFAT_EOF_CLUSTER;
1114 } else {
1115 ret = exfat_get_next_cluster(sb, &clu.dir);
1116 }
1117
1118 if (ret || clu.dir == EXFAT_EOF_CLUSTER) {
1119
1120 hint_stat->clu = p_dir->dir;
1121 hint_stat->eidx = 0;
1122 return (dentry - num_ext);
1123 }
1124 }
1125
1126 hint_stat->clu = clu.dir;
1127 hint_stat->eidx = dentry + 1;
1128 return dentry - num_ext;
1129}
1130
1131int exfat_count_ext_entries(struct super_block *sb, struct exfat_chain *p_dir,
1132 int entry, struct exfat_dentry *ep)
1133{
1134 int i, count = 0;
1135 unsigned int type;
1136 struct exfat_dentry *ext_ep;
1137 struct buffer_head *bh;
1138
1139 for (i = 0, entry++; i < ep->dentry.file.num_ext; i++, entry++) {
1140 ext_ep = exfat_get_dentry(sb, p_dir, entry, &bh);
1141 if (!ext_ep)
1142 return -EIO;
1143
1144 type = exfat_get_entry_type(ext_ep);
1145 brelse(bh);
1146 if (type == TYPE_EXTEND || type == TYPE_STREAM)
1147 count++;
1148 else
1149 break;
1150 }
1151 return count;
1152}
1153
1154int exfat_count_dir_entries(struct super_block *sb, struct exfat_chain *p_dir)
1155{
1156 int i, count = 0;
1157 int dentries_per_clu;
1158 unsigned int entry_type;
1159 struct exfat_chain clu;
1160 struct exfat_dentry *ep;
1161 struct exfat_sb_info *sbi = EXFAT_SB(sb);
1162 struct buffer_head *bh;
1163
1164 dentries_per_clu = sbi->dentries_per_clu;
1165
1166 exfat_chain_dup(&clu, p_dir);
1167
1168 while (clu.dir != EXFAT_EOF_CLUSTER) {
1169 for (i = 0; i < dentries_per_clu; i++) {
1170 ep = exfat_get_dentry(sb, &clu, i, &bh);
1171 if (!ep)
1172 return -EIO;
1173 entry_type = exfat_get_entry_type(ep);
1174 brelse(bh);
1175
1176 if (entry_type == TYPE_UNUSED)
1177 return count;
1178 if (entry_type != TYPE_DIR)
1179 continue;
1180 count++;
1181 }
1182
1183 if (clu.flags == ALLOC_NO_FAT_CHAIN) {
1184 if (--clu.size > 0)
1185 clu.dir++;
1186 else
1187 clu.dir = EXFAT_EOF_CLUSTER;
1188 } else {
1189 if (exfat_get_next_cluster(sb, &(clu.dir)))
1190 return -EIO;
1191 }
1192 }
1193
1194 return count;
1195}
1196
