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Merge tag 'mm-hotfixes-stable-2025-07-11-16-16' of git://git.kernel.org/pub/scm/linux...
[linux-block.git] / fs / exfat / namei.c
... / ...
CommitLineData
1// SPDX-License-Identifier: GPL-2.0-or-later
2/*
3 * Copyright (C) 2012-2013 Samsung Electronics Co., Ltd.
4 */
5
6#include <linux/iversion.h>
7#include <linux/namei.h>
8#include <linux/slab.h>
9#include <linux/buffer_head.h>
10#include <linux/nls.h>
11
12#include "exfat_raw.h"
13#include "exfat_fs.h"
14
15static inline unsigned long exfat_d_version(struct dentry *dentry)
16{
17 return (unsigned long) dentry->d_fsdata;
18}
19
20static inline void exfat_d_version_set(struct dentry *dentry,
21 unsigned long version)
22{
23 dentry->d_fsdata = (void *) version;
24}
25
26/*
27 * If new entry was created in the parent, it could create the 8.3 alias (the
28 * shortname of logname). So, the parent may have the negative-dentry which
29 * matches the created 8.3 alias.
30 *
31 * If it happened, the negative dentry isn't actually negative anymore. So,
32 * drop it.
33 */
34static int exfat_d_revalidate(struct inode *dir, const struct qstr *name,
35 struct dentry *dentry, unsigned int flags)
36{
37 if (flags & LOOKUP_RCU)
38 return -ECHILD;
39
40 /*
41 * This is not negative dentry. Always valid.
42 *
43 * Note, rename() to existing directory entry will have ->d_inode, and
44 * will use existing name which isn't specified name by user.
45 *
46 * We may be able to drop this positive dentry here. But dropping
47 * positive dentry isn't good idea. So it's unsupported like
48 * rename("filename", "FILENAME") for now.
49 */
50 if (d_really_is_positive(dentry))
51 return 1;
52
53 /*
54 * Drop the negative dentry, in order to make sure to use the case
55 * sensitive name which is specified by user if this is for creation.
56 */
57 if (flags & (LOOKUP_CREATE | LOOKUP_RENAME_TARGET))
58 return 0;
59
60 return inode_eq_iversion(dir, exfat_d_version(dentry));
61}
62
63/* returns the length of a struct qstr, ignoring trailing dots if necessary */
64static unsigned int exfat_striptail_len(unsigned int len, const char *name,
65 bool keep_last_dots)
66{
67 if (!keep_last_dots) {
68 while (len && name[len - 1] == '.')
69 len--;
70 }
71 return len;
72}
73
74/*
75 * Compute the hash for the exfat name corresponding to the dentry. If the name
76 * is invalid, we leave the hash code unchanged so that the existing dentry can
77 * be used. The exfat fs routines will return ENOENT or EINVAL as appropriate.
78 */
79static int exfat_d_hash(const struct dentry *dentry, struct qstr *qstr)
80{
81 struct super_block *sb = dentry->d_sb;
82 struct nls_table *t = EXFAT_SB(sb)->nls_io;
83 const unsigned char *name = qstr->name;
84 unsigned int len = exfat_striptail_len(qstr->len, qstr->name,
85 EXFAT_SB(sb)->options.keep_last_dots);
86 unsigned long hash = init_name_hash(dentry);
87 int i, charlen;
88 wchar_t c;
89
90 for (i = 0; i < len; i += charlen) {
91 charlen = t->char2uni(&name[i], len - i, &c);
92 if (charlen < 0)
93 return charlen;
94 hash = partial_name_hash(exfat_toupper(sb, c), hash);
95 }
96
97 qstr->hash = end_name_hash(hash);
98 return 0;
99}
100
101static int exfat_d_cmp(const struct dentry *dentry, unsigned int len,
102 const char *str, const struct qstr *name)
103{
104 struct super_block *sb = dentry->d_sb;
105 struct nls_table *t = EXFAT_SB(sb)->nls_io;
106 unsigned int alen = exfat_striptail_len(name->len, name->name,
107 EXFAT_SB(sb)->options.keep_last_dots);
108 unsigned int blen = exfat_striptail_len(len, str,
109 EXFAT_SB(sb)->options.keep_last_dots);
110 wchar_t c1, c2;
111 int charlen, i;
112
113 if (alen != blen)
114 return 1;
115
116 for (i = 0; i < len; i += charlen) {
117 charlen = t->char2uni(&name->name[i], alen - i, &c1);
118 if (charlen < 0)
119 return 1;
120 if (charlen != t->char2uni(&str[i], blen - i, &c2))
121 return 1;
122
123 if (exfat_toupper(sb, c1) != exfat_toupper(sb, c2))
124 return 1;
125 }
126
127 return 0;
128}
129
130const struct dentry_operations exfat_dentry_ops = {
131 .d_revalidate = exfat_d_revalidate,
132 .d_hash = exfat_d_hash,
133 .d_compare = exfat_d_cmp,
134};
135
136static int exfat_utf8_d_hash(const struct dentry *dentry, struct qstr *qstr)
137{
138 struct super_block *sb = dentry->d_sb;
139 const unsigned char *name = qstr->name;
140 unsigned int len = exfat_striptail_len(qstr->len, qstr->name,
141 EXFAT_SB(sb)->options.keep_last_dots);
142 unsigned long hash = init_name_hash(dentry);
143 int i, charlen;
144 unicode_t u;
145
146 for (i = 0; i < len; i += charlen) {
147 charlen = utf8_to_utf32(&name[i], len - i, &u);
148 if (charlen < 0)
149 return charlen;
150
151 /*
152 * exfat_toupper() works only for code points up to the U+FFFF.
153 */
154 hash = partial_name_hash(u <= 0xFFFF ? exfat_toupper(sb, u) : u,
155 hash);
156 }
157
158 qstr->hash = end_name_hash(hash);
159 return 0;
160}
161
162static int exfat_utf8_d_cmp(const struct dentry *dentry, unsigned int len,
163 const char *str, const struct qstr *name)
164{
165 struct super_block *sb = dentry->d_sb;
166 unsigned int alen = exfat_striptail_len(name->len, name->name,
167 EXFAT_SB(sb)->options.keep_last_dots);
168 unsigned int blen = exfat_striptail_len(len, str,
169 EXFAT_SB(sb)->options.keep_last_dots);
170
171 unicode_t u_a, u_b;
172 int charlen, i;
173
174 if (alen != blen)
175 return 1;
176
177 for (i = 0; i < alen; i += charlen) {
178 charlen = utf8_to_utf32(&name->name[i], alen - i, &u_a);
179 if (charlen < 0)
180 return 1;
181 if (charlen != utf8_to_utf32(&str[i], blen - i, &u_b))
182 return 1;
183
184 if (u_a <= 0xFFFF && u_b <= 0xFFFF) {
185 if (exfat_toupper(sb, u_a) != exfat_toupper(sb, u_b))
186 return 1;
187 } else {
188 if (u_a != u_b)
189 return 1;
190 }
191 }
192
193 return 0;
194}
195
196const struct dentry_operations exfat_utf8_dentry_ops = {
197 .d_revalidate = exfat_d_revalidate,
198 .d_hash = exfat_utf8_d_hash,
199 .d_compare = exfat_utf8_d_cmp,
200};
201
202/* search EMPTY CONTINUOUS "num_entries" entries */
203static int exfat_search_empty_slot(struct super_block *sb,
204 struct exfat_hint_femp *hint_femp, struct exfat_chain *p_dir,
205 int num_entries, struct exfat_entry_set_cache *es)
206{
207 int i, dentry, ret;
208 int dentries_per_clu;
209 struct exfat_chain clu;
210 struct exfat_sb_info *sbi = EXFAT_SB(sb);
211 int total_entries = EXFAT_CLU_TO_DEN(p_dir->size, sbi);
212
213 dentries_per_clu = sbi->dentries_per_clu;
214
215 if (hint_femp->eidx != EXFAT_HINT_NONE) {
216 dentry = hint_femp->eidx;
217
218 /*
219 * If hint_femp->count is enough, it is needed to check if
220 * there are actual empty entries.
221 * Otherwise, and if "dentry + hint_famp->count" is also equal
222 * to "p_dir->size * dentries_per_clu", it means ENOSPC.
223 */
224 if (dentry + hint_femp->count == total_entries &&
225 num_entries > hint_femp->count)
226 return -ENOSPC;
227
228 hint_femp->eidx = EXFAT_HINT_NONE;
229 exfat_chain_dup(&clu, &hint_femp->cur);
230 } else {
231 exfat_chain_dup(&clu, p_dir);
232 dentry = 0;
233 }
234
235 while (dentry + num_entries <= total_entries &&
236 clu.dir != EXFAT_EOF_CLUSTER) {
237 i = dentry & (dentries_per_clu - 1);
238
239 ret = exfat_get_empty_dentry_set(es, sb, &clu, i, num_entries);
240 if (ret < 0)
241 return ret;
242 else if (ret == 0)
243 return dentry;
244
245 dentry += ret;
246 i += ret;
247
248 while (i >= dentries_per_clu) {
249 if (clu.flags == ALLOC_NO_FAT_CHAIN) {
250 if (--clu.size > 0)
251 clu.dir++;
252 else
253 clu.dir = EXFAT_EOF_CLUSTER;
254 } else {
255 if (exfat_get_next_cluster(sb, &clu.dir))
256 return -EIO;
257 }
258
259 i -= dentries_per_clu;
260 }
261 }
262
263 hint_femp->eidx = dentry;
264 hint_femp->count = 0;
265 if (dentry == total_entries || clu.dir == EXFAT_EOF_CLUSTER)
266 exfat_chain_set(&hint_femp->cur, EXFAT_EOF_CLUSTER, 0,
267 clu.flags);
268 else
269 hint_femp->cur = clu;
270
271 return -ENOSPC;
272}
273
274static int exfat_check_max_dentries(struct inode *inode)
275{
276 if (EXFAT_B_TO_DEN(i_size_read(inode)) >= MAX_EXFAT_DENTRIES) {
277 /*
278 * exFAT spec allows a dir to grow up to 8388608(256MB)
279 * dentries
280 */
281 return -ENOSPC;
282 }
283 return 0;
284}
285
286/*
287 * Find an empty directory entry set.
288 *
289 * If there isn't any empty slot, expand cluster chain.
290 *
291 * in:
292 * inode: inode of the parent directory
293 * num_entries: specifies how many dentries in the empty directory entry set
294 *
295 * out:
296 * p_dir: the cluster where the empty directory entry set is located
297 * es: The found empty directory entry set
298 *
299 * return:
300 * the directory entry index in p_dir is returned on succeeds
301 * -error code is returned on failure
302 */
303static int exfat_find_empty_entry(struct inode *inode,
304 struct exfat_chain *p_dir, int num_entries,
305 struct exfat_entry_set_cache *es)
306{
307 int dentry;
308 unsigned int ret, last_clu;
309 loff_t size = 0;
310 struct exfat_chain clu;
311 struct super_block *sb = inode->i_sb;
312 struct exfat_sb_info *sbi = EXFAT_SB(sb);
313 struct exfat_inode_info *ei = EXFAT_I(inode);
314 struct exfat_hint_femp hint_femp;
315
316 hint_femp.eidx = EXFAT_HINT_NONE;
317
318 if (ei->hint_femp.eidx != EXFAT_HINT_NONE) {
319 hint_femp = ei->hint_femp;
320 ei->hint_femp.eidx = EXFAT_HINT_NONE;
321 }
322
323 exfat_chain_set(p_dir, ei->start_clu,
324 EXFAT_B_TO_CLU(i_size_read(inode), sbi), ei->flags);
325
326 while ((dentry = exfat_search_empty_slot(sb, &hint_femp, p_dir,
327 num_entries, es)) < 0) {
328 if (dentry != -ENOSPC)
329 return dentry;
330
331 if (exfat_check_max_dentries(inode))
332 return -ENOSPC;
333
334 /*
335 * Allocate new cluster to this directory
336 */
337 if (ei->start_clu != EXFAT_EOF_CLUSTER) {
338 /* we trust p_dir->size regardless of FAT type */
339 if (exfat_find_last_cluster(sb, p_dir, &last_clu))
340 return -EIO;
341
342 exfat_chain_set(&clu, last_clu + 1, 0, p_dir->flags);
343 } else {
344 /* This directory is empty */
345 exfat_chain_set(&clu, EXFAT_EOF_CLUSTER, 0,
346 ALLOC_NO_FAT_CHAIN);
347 }
348
349 /* allocate a cluster */
350 ret = exfat_alloc_cluster(inode, 1, &clu, IS_DIRSYNC(inode));
351 if (ret)
352 return ret;
353
354 if (exfat_zeroed_cluster(inode, clu.dir))
355 return -EIO;
356
357 if (ei->start_clu == EXFAT_EOF_CLUSTER) {
358 ei->start_clu = clu.dir;
359 p_dir->dir = clu.dir;
360 hint_femp.eidx = 0;
361 }
362
363 /* append to the FAT chain */
364 if (clu.flags != p_dir->flags) {
365 /* no-fat-chain bit is disabled,
366 * so fat-chain should be synced with alloc-bitmap
367 */
368 exfat_chain_cont_cluster(sb, p_dir->dir, p_dir->size);
369 p_dir->flags = ALLOC_FAT_CHAIN;
370 hint_femp.cur.flags = ALLOC_FAT_CHAIN;
371 }
372
373 if (clu.flags == ALLOC_FAT_CHAIN)
374 if (exfat_ent_set(sb, last_clu, clu.dir))
375 return -EIO;
376
377 if (hint_femp.cur.dir == EXFAT_EOF_CLUSTER)
378 exfat_chain_set(&hint_femp.cur, clu.dir, 0, clu.flags);
379
380 hint_femp.count += sbi->dentries_per_clu;
381
382 hint_femp.cur.size++;
383 p_dir->size++;
384 size = EXFAT_CLU_TO_B(p_dir->size, sbi);
385
386 /* directory inode should be updated in here */
387 i_size_write(inode, size);
388 ei->valid_size += sbi->cluster_size;
389 ei->flags = p_dir->flags;
390 inode->i_blocks += sbi->cluster_size >> 9;
391 }
392
393 p_dir->dir = exfat_sector_to_cluster(sbi, es->bh[0]->b_blocknr);
394 p_dir->size -= dentry / sbi->dentries_per_clu;
395
396 return dentry & (sbi->dentries_per_clu - 1);
397}
398
399/*
400 * Name Resolution Functions :
401 * Zero if it was successful; otherwise nonzero.
402 */
403static int __exfat_resolve_path(struct inode *inode, const unsigned char *path,
404 struct exfat_uni_name *p_uniname, int lookup)
405{
406 int namelen;
407 int lossy = NLS_NAME_NO_LOSSY;
408 struct super_block *sb = inode->i_sb;
409 int pathlen = strlen(path);
410
411 /*
412 * get the length of the pathname excluding
413 * trailing periods, if any.
414 */
415 namelen = exfat_striptail_len(pathlen, path, false);
416 if (EXFAT_SB(sb)->options.keep_last_dots) {
417 /*
418 * Do not allow the creation of files with names
419 * ending with period(s).
420 */
421 if (!lookup && (namelen < pathlen))
422 return -EINVAL;
423 namelen = pathlen;
424 }
425 if (!namelen)
426 return -ENOENT;
427 if (pathlen > (MAX_NAME_LENGTH * MAX_CHARSET_SIZE))
428 return -ENAMETOOLONG;
429
430 /*
431 * strip all leading spaces :
432 * "MS windows 7" supports leading spaces.
433 * So we should skip this preprocessing for compatibility.
434 */
435
436 /* file name conversion :
437 * If lookup case, we allow bad-name for compatibility.
438 */
439 namelen = exfat_nls_to_utf16(sb, path, namelen, p_uniname,
440 &lossy);
441 if (namelen < 0)
442 return namelen; /* return error value */
443
444 if ((lossy && !lookup) || !namelen)
445 return (lossy & NLS_NAME_OVERLEN) ? -ENAMETOOLONG : -EINVAL;
446
447 return 0;
448}
449
450static inline int exfat_resolve_path(struct inode *inode,
451 const unsigned char *path, struct exfat_uni_name *uni)
452{
453 return __exfat_resolve_path(inode, path, uni, 0);
454}
455
456static inline int exfat_resolve_path_for_lookup(struct inode *inode,
457 const unsigned char *path, struct exfat_uni_name *uni)
458{
459 return __exfat_resolve_path(inode, path, uni, 1);
460}
461
462static inline loff_t exfat_make_i_pos(struct exfat_dir_entry *info)
463{
464 return ((loff_t) info->dir.dir << 32) | (info->entry & 0xffffffff);
465}
466
467static int exfat_add_entry(struct inode *inode, const char *path,
468 unsigned int type, struct exfat_dir_entry *info)
469{
470 int ret, dentry, num_entries;
471 struct super_block *sb = inode->i_sb;
472 struct exfat_sb_info *sbi = EXFAT_SB(sb);
473 struct exfat_uni_name uniname;
474 struct exfat_chain clu;
475 struct timespec64 ts = current_time(inode);
476 struct exfat_entry_set_cache es;
477 int clu_size = 0;
478 unsigned int start_clu = EXFAT_FREE_CLUSTER;
479
480 ret = exfat_resolve_path(inode, path, &uniname);
481 if (ret)
482 goto out;
483
484 num_entries = exfat_calc_num_entries(&uniname);
485 if (num_entries < 0) {
486 ret = num_entries;
487 goto out;
488 }
489
490 /* exfat_find_empty_entry must be called before alloc_cluster() */
491 dentry = exfat_find_empty_entry(inode, &info->dir, num_entries, &es);
492 if (dentry < 0) {
493 ret = dentry; /* -EIO or -ENOSPC */
494 goto out;
495 }
496
497 if (type == TYPE_DIR && !sbi->options.zero_size_dir) {
498 ret = exfat_alloc_new_dir(inode, &clu);
499 if (ret) {
500 exfat_put_dentry_set(&es, false);
501 goto out;
502 }
503 start_clu = clu.dir;
504 clu_size = sbi->cluster_size;
505 }
506
507 /* update the directory entry */
508 /* fill the dos name directory entry information of the created file.
509 * the first cluster is not determined yet. (0)
510 */
511 exfat_init_dir_entry(&es, type, start_clu, clu_size, &ts);
512 exfat_init_ext_entry(&es, num_entries, &uniname);
513
514 ret = exfat_put_dentry_set(&es, IS_DIRSYNC(inode));
515 if (ret)
516 goto out;
517
518 info->entry = dentry;
519 info->flags = ALLOC_NO_FAT_CHAIN;
520 info->type = type;
521
522 if (type == TYPE_FILE) {
523 info->attr = EXFAT_ATTR_ARCHIVE;
524 info->start_clu = EXFAT_EOF_CLUSTER;
525 info->size = 0;
526 info->num_subdirs = 0;
527 } else {
528 info->attr = EXFAT_ATTR_SUBDIR;
529 if (sbi->options.zero_size_dir)
530 info->start_clu = EXFAT_EOF_CLUSTER;
531 else
532 info->start_clu = start_clu;
533 info->size = clu_size;
534 info->num_subdirs = EXFAT_MIN_SUBDIR;
535 }
536 info->valid_size = info->size;
537
538 memset(&info->crtime, 0, sizeof(info->crtime));
539 memset(&info->mtime, 0, sizeof(info->mtime));
540 memset(&info->atime, 0, sizeof(info->atime));
541out:
542 return ret;
543}
544
545static int exfat_create(struct mnt_idmap *idmap, struct inode *dir,
546 struct dentry *dentry, umode_t mode, bool excl)
547{
548 struct super_block *sb = dir->i_sb;
549 struct inode *inode;
550 struct exfat_dir_entry info;
551 loff_t i_pos;
552 int err;
553 loff_t size = i_size_read(dir);
554
555 if (unlikely(exfat_forced_shutdown(sb)))
556 return -EIO;
557
558 mutex_lock(&EXFAT_SB(sb)->s_lock);
559 exfat_set_volume_dirty(sb);
560 err = exfat_add_entry(dir, dentry->d_name.name, TYPE_FILE, &info);
561 if (err)
562 goto unlock;
563
564 inode_inc_iversion(dir);
565 inode_set_mtime_to_ts(dir, inode_set_ctime_current(dir));
566 if (IS_DIRSYNC(dir) && size != i_size_read(dir))
567 exfat_sync_inode(dir);
568 else
569 mark_inode_dirty(dir);
570
571 i_pos = exfat_make_i_pos(&info);
572 inode = exfat_build_inode(sb, &info, i_pos);
573 err = PTR_ERR_OR_ZERO(inode);
574 if (err)
575 goto unlock;
576
577 inode_inc_iversion(inode);
578 EXFAT_I(inode)->i_crtime = simple_inode_init_ts(inode);
579 exfat_truncate_inode_atime(inode);
580
581 /* timestamp is already written, so mark_inode_dirty() is unneeded. */
582
583 d_instantiate(dentry, inode);
584unlock:
585 mutex_unlock(&EXFAT_SB(sb)->s_lock);
586 return err;
587}
588
589/* lookup a file */
590static int exfat_find(struct inode *dir, struct qstr *qname,
591 struct exfat_dir_entry *info)
592{
593 int ret, dentry, count;
594 struct exfat_chain cdir;
595 struct exfat_uni_name uni_name;
596 struct super_block *sb = dir->i_sb;
597 struct exfat_sb_info *sbi = EXFAT_SB(sb);
598 struct exfat_inode_info *ei = EXFAT_I(dir);
599 struct exfat_dentry *ep, *ep2;
600 struct exfat_entry_set_cache es;
601 /* for optimized dir & entry to prevent long traverse of cluster chain */
602 struct exfat_hint hint_opt;
603
604 if (qname->len == 0)
605 return -ENOENT;
606
607 /* check the validity of directory name in the given pathname */
608 ret = exfat_resolve_path_for_lookup(dir, qname->name, &uni_name);
609 if (ret)
610 return ret;
611
612 exfat_chain_set(&cdir, ei->start_clu,
613 EXFAT_B_TO_CLU(i_size_read(dir), sbi), ei->flags);
614
615 /* check the validation of hint_stat and initialize it if required */
616 if (ei->version != (inode_peek_iversion_raw(dir) & 0xffffffff)) {
617 ei->hint_stat.clu = cdir.dir;
618 ei->hint_stat.eidx = 0;
619 ei->version = (inode_peek_iversion_raw(dir) & 0xffffffff);
620 ei->hint_femp.eidx = EXFAT_HINT_NONE;
621 }
622
623 /* search the file name for directories */
624 dentry = exfat_find_dir_entry(sb, ei, &cdir, &uni_name, &hint_opt);
625 if (dentry < 0)
626 return dentry; /* -error value */
627
628 /* adjust cdir to the optimized value */
629 cdir.dir = hint_opt.clu;
630 if (cdir.flags & ALLOC_NO_FAT_CHAIN)
631 cdir.size -= dentry / sbi->dentries_per_clu;
632 dentry = hint_opt.eidx;
633
634 info->dir = cdir;
635 info->entry = dentry;
636 info->num_subdirs = 0;
637
638 if (exfat_get_dentry_set(&es, sb, &cdir, dentry, ES_2_ENTRIES))
639 return -EIO;
640 ep = exfat_get_dentry_cached(&es, ES_IDX_FILE);
641 ep2 = exfat_get_dentry_cached(&es, ES_IDX_STREAM);
642
643 info->type = exfat_get_entry_type(ep);
644 info->attr = le16_to_cpu(ep->dentry.file.attr);
645 info->size = le64_to_cpu(ep2->dentry.stream.valid_size);
646 info->valid_size = le64_to_cpu(ep2->dentry.stream.valid_size);
647 info->size = le64_to_cpu(ep2->dentry.stream.size);
648
649 if (unlikely(EXFAT_B_TO_CLU_ROUND_UP(info->size, sbi) > sbi->used_clusters)) {
650 exfat_fs_error(sb, "data size is invalid(%lld)", info->size);
651 return -EIO;
652 }
653
654 info->start_clu = le32_to_cpu(ep2->dentry.stream.start_clu);
655 if (!is_valid_cluster(sbi, info->start_clu) && info->size) {
656 exfat_warn(sb, "start_clu is invalid cluster(0x%x)",
657 info->start_clu);
658 info->size = 0;
659 info->valid_size = 0;
660 }
661
662 if (info->valid_size > info->size) {
663 exfat_warn(sb, "valid_size(%lld) is greater than size(%lld)",
664 info->valid_size, info->size);
665 info->valid_size = info->size;
666 }
667
668 if (info->size == 0) {
669 info->flags = ALLOC_NO_FAT_CHAIN;
670 info->start_clu = EXFAT_EOF_CLUSTER;
671 } else
672 info->flags = ep2->dentry.stream.flags;
673
674 exfat_get_entry_time(sbi, &info->crtime,
675 ep->dentry.file.create_tz,
676 ep->dentry.file.create_time,
677 ep->dentry.file.create_date,
678 ep->dentry.file.create_time_cs);
679 exfat_get_entry_time(sbi, &info->mtime,
680 ep->dentry.file.modify_tz,
681 ep->dentry.file.modify_time,
682 ep->dentry.file.modify_date,
683 ep->dentry.file.modify_time_cs);
684 exfat_get_entry_time(sbi, &info->atime,
685 ep->dentry.file.access_tz,
686 ep->dentry.file.access_time,
687 ep->dentry.file.access_date,
688 0);
689 exfat_put_dentry_set(&es, false);
690
691 if (ei->start_clu == EXFAT_FREE_CLUSTER) {
692 exfat_fs_error(sb,
693 "non-zero size file starts with zero cluster (size : %llu, p_dir : %u, entry : 0x%08x)",
694 i_size_read(dir), ei->dir.dir, ei->entry);
695 return -EIO;
696 }
697
698 if (info->type == TYPE_DIR) {
699 exfat_chain_set(&cdir, info->start_clu,
700 EXFAT_B_TO_CLU(info->size, sbi), info->flags);
701 count = exfat_count_dir_entries(sb, &cdir);
702 if (count < 0)
703 return -EIO;
704
705 info->num_subdirs = count + EXFAT_MIN_SUBDIR;
706 }
707 return 0;
708}
709
710static int exfat_d_anon_disconn(struct dentry *dentry)
711{
712 return IS_ROOT(dentry) && (dentry->d_flags & DCACHE_DISCONNECTED);
713}
714
715static struct dentry *exfat_lookup(struct inode *dir, struct dentry *dentry,
716 unsigned int flags)
717{
718 struct super_block *sb = dir->i_sb;
719 struct inode *inode;
720 struct dentry *alias;
721 struct exfat_dir_entry info;
722 int err;
723 loff_t i_pos;
724 mode_t i_mode;
725
726 mutex_lock(&EXFAT_SB(sb)->s_lock);
727 err = exfat_find(dir, &dentry->d_name, &info);
728 if (err) {
729 if (err == -ENOENT) {
730 inode = NULL;
731 goto out;
732 }
733 goto unlock;
734 }
735
736 i_pos = exfat_make_i_pos(&info);
737 inode = exfat_build_inode(sb, &info, i_pos);
738 err = PTR_ERR_OR_ZERO(inode);
739 if (err)
740 goto unlock;
741
742 i_mode = inode->i_mode;
743 alias = d_find_alias(inode);
744
745 /*
746 * Checking "alias->d_parent == dentry->d_parent" to make sure
747 * FS is not corrupted (especially double linked dir).
748 */
749 if (alias && alias->d_parent == dentry->d_parent &&
750 !exfat_d_anon_disconn(alias)) {
751
752 /*
753 * Unhashed alias is able to exist because of revalidate()
754 * called by lookup_fast. You can easily make this status
755 * by calling create and lookup concurrently
756 * In such case, we reuse an alias instead of new dentry
757 */
758 if (d_unhashed(alias)) {
759 WARN_ON(alias->d_name.hash_len !=
760 dentry->d_name.hash_len);
761 exfat_info(sb, "rehashed a dentry(%p) in read lookup",
762 alias);
763 d_drop(dentry);
764 d_rehash(alias);
765 } else if (!S_ISDIR(i_mode)) {
766 /*
767 * This inode has non anonymous-DCACHE_DISCONNECTED
768 * dentry. This means, the user did ->lookup() by an
769 * another name (longname vs 8.3 alias of it) in past.
770 *
771 * Switch to new one for reason of locality if possible.
772 */
773 d_move(alias, dentry);
774 }
775 iput(inode);
776 mutex_unlock(&EXFAT_SB(sb)->s_lock);
777 return alias;
778 }
779 dput(alias);
780out:
781 mutex_unlock(&EXFAT_SB(sb)->s_lock);
782 if (!inode)
783 exfat_d_version_set(dentry, inode_query_iversion(dir));
784
785 return d_splice_alias(inode, dentry);
786unlock:
787 mutex_unlock(&EXFAT_SB(sb)->s_lock);
788 return ERR_PTR(err);
789}
790
791/* remove an entry, BUT don't truncate */
792static int exfat_unlink(struct inode *dir, struct dentry *dentry)
793{
794 struct super_block *sb = dir->i_sb;
795 struct inode *inode = dentry->d_inode;
796 struct exfat_inode_info *ei = EXFAT_I(inode);
797 struct exfat_entry_set_cache es;
798 int err = 0;
799
800 if (unlikely(exfat_forced_shutdown(sb)))
801 return -EIO;
802
803 mutex_lock(&EXFAT_SB(sb)->s_lock);
804 if (ei->dir.dir == DIR_DELETED) {
805 exfat_err(sb, "abnormal access to deleted dentry");
806 err = -ENOENT;
807 goto unlock;
808 }
809
810 err = exfat_get_dentry_set_by_ei(&es, sb, ei);
811 if (err) {
812 err = -EIO;
813 goto unlock;
814 }
815
816 exfat_set_volume_dirty(sb);
817
818 /* update the directory entry */
819 exfat_remove_entries(inode, &es, ES_IDX_FILE);
820
821 err = exfat_put_dentry_set(&es, IS_DIRSYNC(inode));
822 if (err)
823 goto unlock;
824
825 /* This doesn't modify ei */
826 ei->dir.dir = DIR_DELETED;
827
828 inode_inc_iversion(dir);
829 simple_inode_init_ts(dir);
830 exfat_truncate_inode_atime(dir);
831 mark_inode_dirty(dir);
832
833 clear_nlink(inode);
834 simple_inode_init_ts(inode);
835 exfat_truncate_inode_atime(inode);
836 exfat_unhash_inode(inode);
837 exfat_d_version_set(dentry, inode_query_iversion(dir));
838unlock:
839 mutex_unlock(&EXFAT_SB(sb)->s_lock);
840 return err;
841}
842
843static struct dentry *exfat_mkdir(struct mnt_idmap *idmap, struct inode *dir,
844 struct dentry *dentry, umode_t mode)
845{
846 struct super_block *sb = dir->i_sb;
847 struct inode *inode;
848 struct exfat_dir_entry info;
849 loff_t i_pos;
850 int err;
851 loff_t size = i_size_read(dir);
852
853 if (unlikely(exfat_forced_shutdown(sb)))
854 return ERR_PTR(-EIO);
855
856 mutex_lock(&EXFAT_SB(sb)->s_lock);
857 exfat_set_volume_dirty(sb);
858 err = exfat_add_entry(dir, dentry->d_name.name, TYPE_DIR, &info);
859 if (err)
860 goto unlock;
861
862 inode_inc_iversion(dir);
863 inode_set_mtime_to_ts(dir, inode_set_ctime_current(dir));
864 if (IS_DIRSYNC(dir) && size != i_size_read(dir))
865 exfat_sync_inode(dir);
866 else
867 mark_inode_dirty(dir);
868 inc_nlink(dir);
869
870 i_pos = exfat_make_i_pos(&info);
871 inode = exfat_build_inode(sb, &info, i_pos);
872 err = PTR_ERR_OR_ZERO(inode);
873 if (err)
874 goto unlock;
875
876 inode_inc_iversion(inode);
877 EXFAT_I(inode)->i_crtime = simple_inode_init_ts(inode);
878 exfat_truncate_inode_atime(inode);
879 /* timestamp is already written, so mark_inode_dirty() is unneeded. */
880
881 d_instantiate(dentry, inode);
882
883unlock:
884 mutex_unlock(&EXFAT_SB(sb)->s_lock);
885 return ERR_PTR(err);
886}
887
888static int exfat_check_dir_empty(struct super_block *sb,
889 struct exfat_chain *p_dir)
890{
891 int i, dentries_per_clu;
892 unsigned int type;
893 struct exfat_chain clu;
894 struct exfat_dentry *ep;
895 struct exfat_sb_info *sbi = EXFAT_SB(sb);
896 struct buffer_head *bh;
897
898 dentries_per_clu = sbi->dentries_per_clu;
899
900 if (p_dir->dir == EXFAT_EOF_CLUSTER)
901 return 0;
902
903 exfat_chain_dup(&clu, p_dir);
904
905 while (clu.dir != EXFAT_EOF_CLUSTER) {
906 for (i = 0; i < dentries_per_clu; i++) {
907 ep = exfat_get_dentry(sb, &clu, i, &bh);
908 if (!ep)
909 return -EIO;
910 type = exfat_get_entry_type(ep);
911 brelse(bh);
912 if (type == TYPE_UNUSED)
913 return 0;
914
915 if (type != TYPE_FILE && type != TYPE_DIR)
916 continue;
917
918 return -ENOTEMPTY;
919 }
920
921 if (clu.flags == ALLOC_NO_FAT_CHAIN) {
922 if (--clu.size > 0)
923 clu.dir++;
924 else
925 clu.dir = EXFAT_EOF_CLUSTER;
926 } else {
927 if (exfat_get_next_cluster(sb, &(clu.dir)))
928 return -EIO;
929 }
930 }
931
932 return 0;
933}
934
935static int exfat_rmdir(struct inode *dir, struct dentry *dentry)
936{
937 struct inode *inode = dentry->d_inode;
938 struct exfat_chain clu_to_free;
939 struct super_block *sb = inode->i_sb;
940 struct exfat_sb_info *sbi = EXFAT_SB(sb);
941 struct exfat_inode_info *ei = EXFAT_I(inode);
942 struct exfat_entry_set_cache es;
943 int err;
944
945 if (unlikely(exfat_forced_shutdown(sb)))
946 return -EIO;
947
948 mutex_lock(&EXFAT_SB(inode->i_sb)->s_lock);
949
950 if (ei->dir.dir == DIR_DELETED) {
951 exfat_err(sb, "abnormal access to deleted dentry");
952 err = -ENOENT;
953 goto unlock;
954 }
955
956 exfat_chain_set(&clu_to_free, ei->start_clu,
957 EXFAT_B_TO_CLU_ROUND_UP(i_size_read(inode), sbi), ei->flags);
958
959 err = exfat_check_dir_empty(sb, &clu_to_free);
960 if (err) {
961 if (err == -EIO)
962 exfat_err(sb, "failed to exfat_check_dir_empty : err(%d)",
963 err);
964 goto unlock;
965 }
966
967 err = exfat_get_dentry_set_by_ei(&es, sb, ei);
968 if (err) {
969 err = -EIO;
970 goto unlock;
971 }
972
973 exfat_set_volume_dirty(sb);
974
975 exfat_remove_entries(inode, &es, ES_IDX_FILE);
976
977 err = exfat_put_dentry_set(&es, IS_DIRSYNC(dir));
978 if (err)
979 goto unlock;
980
981 ei->dir.dir = DIR_DELETED;
982
983 inode_inc_iversion(dir);
984 simple_inode_init_ts(dir);
985 exfat_truncate_inode_atime(dir);
986 if (IS_DIRSYNC(dir))
987 exfat_sync_inode(dir);
988 else
989 mark_inode_dirty(dir);
990 drop_nlink(dir);
991
992 clear_nlink(inode);
993 simple_inode_init_ts(inode);
994 exfat_truncate_inode_atime(inode);
995 exfat_unhash_inode(inode);
996 exfat_d_version_set(dentry, inode_query_iversion(dir));
997unlock:
998 mutex_unlock(&EXFAT_SB(inode->i_sb)->s_lock);
999 return err;
1000}
1001
1002static int exfat_rename_file(struct inode *parent_inode,
1003 struct exfat_uni_name *p_uniname, struct exfat_inode_info *ei)
1004{
1005 int ret, num_new_entries;
1006 struct exfat_dentry *epold, *epnew;
1007 struct super_block *sb = parent_inode->i_sb;
1008 struct exfat_entry_set_cache old_es, new_es;
1009 int sync = IS_DIRSYNC(parent_inode);
1010
1011 if (unlikely(exfat_forced_shutdown(sb)))
1012 return -EIO;
1013
1014 num_new_entries = exfat_calc_num_entries(p_uniname);
1015 if (num_new_entries < 0)
1016 return num_new_entries;
1017
1018 ret = exfat_get_dentry_set_by_ei(&old_es, sb, ei);
1019 if (ret) {
1020 ret = -EIO;
1021 return ret;
1022 }
1023
1024 epold = exfat_get_dentry_cached(&old_es, ES_IDX_FILE);
1025
1026 if (old_es.num_entries < num_new_entries) {
1027 int newentry;
1028 struct exfat_chain dir;
1029
1030 newentry = exfat_find_empty_entry(parent_inode, &dir,
1031 num_new_entries, &new_es);
1032 if (newentry < 0) {
1033 ret = newentry; /* -EIO or -ENOSPC */
1034 goto put_old_es;
1035 }
1036
1037 epnew = exfat_get_dentry_cached(&new_es, ES_IDX_FILE);
1038 *epnew = *epold;
1039 if (exfat_get_entry_type(epnew) == TYPE_FILE) {
1040 epnew->dentry.file.attr |= cpu_to_le16(EXFAT_ATTR_ARCHIVE);
1041 ei->attr |= EXFAT_ATTR_ARCHIVE;
1042 }
1043
1044 epold = exfat_get_dentry_cached(&old_es, ES_IDX_STREAM);
1045 epnew = exfat_get_dentry_cached(&new_es, ES_IDX_STREAM);
1046 *epnew = *epold;
1047
1048 exfat_init_ext_entry(&new_es, num_new_entries, p_uniname);
1049
1050 ret = exfat_put_dentry_set(&new_es, sync);
1051 if (ret)
1052 goto put_old_es;
1053
1054 exfat_remove_entries(parent_inode, &old_es, ES_IDX_FILE);
1055 ei->dir = dir;
1056 ei->entry = newentry;
1057 } else {
1058 if (exfat_get_entry_type(epold) == TYPE_FILE) {
1059 epold->dentry.file.attr |= cpu_to_le16(EXFAT_ATTR_ARCHIVE);
1060 ei->attr |= EXFAT_ATTR_ARCHIVE;
1061 }
1062
1063 exfat_remove_entries(parent_inode, &old_es, ES_IDX_FIRST_FILENAME + 1);
1064 exfat_init_ext_entry(&old_es, num_new_entries, p_uniname);
1065 }
1066 return exfat_put_dentry_set(&old_es, sync);
1067
1068put_old_es:
1069 exfat_put_dentry_set(&old_es, false);
1070 return ret;
1071}
1072
1073static int exfat_move_file(struct inode *parent_inode,
1074 struct exfat_uni_name *p_uniname, struct exfat_inode_info *ei)
1075{
1076 int ret, newentry, num_new_entries;
1077 struct exfat_dentry *epmov, *epnew;
1078 struct exfat_entry_set_cache mov_es, new_es;
1079 struct exfat_chain newdir;
1080
1081 num_new_entries = exfat_calc_num_entries(p_uniname);
1082 if (num_new_entries < 0)
1083 return num_new_entries;
1084
1085 ret = exfat_get_dentry_set_by_ei(&mov_es, parent_inode->i_sb, ei);
1086 if (ret)
1087 return -EIO;
1088
1089 newentry = exfat_find_empty_entry(parent_inode, &newdir,
1090 num_new_entries, &new_es);
1091 if (newentry < 0) {
1092 ret = newentry; /* -EIO or -ENOSPC */
1093 goto put_mov_es;
1094 }
1095
1096 epmov = exfat_get_dentry_cached(&mov_es, ES_IDX_FILE);
1097 epnew = exfat_get_dentry_cached(&new_es, ES_IDX_FILE);
1098 *epnew = *epmov;
1099 if (exfat_get_entry_type(epnew) == TYPE_FILE) {
1100 epnew->dentry.file.attr |= cpu_to_le16(EXFAT_ATTR_ARCHIVE);
1101 ei->attr |= EXFAT_ATTR_ARCHIVE;
1102 }
1103
1104 epmov = exfat_get_dentry_cached(&mov_es, ES_IDX_STREAM);
1105 epnew = exfat_get_dentry_cached(&new_es, ES_IDX_STREAM);
1106 *epnew = *epmov;
1107
1108 exfat_init_ext_entry(&new_es, num_new_entries, p_uniname);
1109 exfat_remove_entries(parent_inode, &mov_es, ES_IDX_FILE);
1110
1111 ei->dir = newdir;
1112 ei->entry = newentry;
1113
1114 ret = exfat_put_dentry_set(&new_es, IS_DIRSYNC(parent_inode));
1115 if (ret)
1116 goto put_mov_es;
1117
1118 return exfat_put_dentry_set(&mov_es, IS_DIRSYNC(parent_inode));
1119
1120put_mov_es:
1121 exfat_put_dentry_set(&mov_es, false);
1122
1123 return ret;
1124}
1125
1126/* rename or move a old file into a new file */
1127static int __exfat_rename(struct inode *old_parent_inode,
1128 struct exfat_inode_info *ei, struct inode *new_parent_inode,
1129 struct dentry *new_dentry)
1130{
1131 int ret;
1132 struct exfat_uni_name uni_name;
1133 struct super_block *sb = old_parent_inode->i_sb;
1134 struct exfat_sb_info *sbi = EXFAT_SB(sb);
1135 const unsigned char *new_path = new_dentry->d_name.name;
1136 struct inode *new_inode = new_dentry->d_inode;
1137 struct exfat_inode_info *new_ei = NULL;
1138
1139 /* check the validity of pointer parameters */
1140 if (new_path == NULL || strlen(new_path) == 0)
1141 return -EINVAL;
1142
1143 if (ei->dir.dir == DIR_DELETED) {
1144 exfat_err(sb, "abnormal access to deleted source dentry");
1145 return -ENOENT;
1146 }
1147
1148 /* check whether new dir is existing directory and empty */
1149 if (new_inode) {
1150 ret = -EIO;
1151 new_ei = EXFAT_I(new_inode);
1152
1153 if (new_ei->dir.dir == DIR_DELETED) {
1154 exfat_err(sb, "abnormal access to deleted target dentry");
1155 goto out;
1156 }
1157
1158 /* if new_inode exists, update ei */
1159 if (S_ISDIR(new_inode->i_mode)) {
1160 struct exfat_chain new_clu;
1161
1162 new_clu.dir = new_ei->start_clu;
1163 new_clu.size =
1164 EXFAT_B_TO_CLU_ROUND_UP(i_size_read(new_inode),
1165 sbi);
1166 new_clu.flags = new_ei->flags;
1167
1168 ret = exfat_check_dir_empty(sb, &new_clu);
1169 if (ret)
1170 goto out;
1171 }
1172 }
1173
1174 /* check the validity of directory name in the given new pathname */
1175 ret = exfat_resolve_path(new_parent_inode, new_path, &uni_name);
1176 if (ret)
1177 goto out;
1178
1179 exfat_set_volume_dirty(sb);
1180
1181 if (new_parent_inode == old_parent_inode)
1182 ret = exfat_rename_file(new_parent_inode, &uni_name, ei);
1183 else
1184 ret = exfat_move_file(new_parent_inode, &uni_name, ei);
1185
1186 if (!ret && new_inode) {
1187 struct exfat_entry_set_cache es;
1188
1189 /* delete entries of new_dir */
1190 ret = exfat_get_dentry_set_by_ei(&es, sb, new_ei);
1191 if (ret) {
1192 ret = -EIO;
1193 goto del_out;
1194 }
1195
1196 exfat_remove_entries(new_inode, &es, ES_IDX_FILE);
1197
1198 ret = exfat_put_dentry_set(&es, IS_DIRSYNC(new_inode));
1199 if (ret)
1200 goto del_out;
1201
1202 /* Free the clusters if new_inode is a dir(as if exfat_rmdir) */
1203 if (S_ISDIR(new_inode->i_mode) &&
1204 new_ei->start_clu != EXFAT_EOF_CLUSTER) {
1205 /* new_ei, new_clu_to_free */
1206 struct exfat_chain new_clu_to_free;
1207
1208 exfat_chain_set(&new_clu_to_free, new_ei->start_clu,
1209 EXFAT_B_TO_CLU_ROUND_UP(i_size_read(new_inode),
1210 sbi), new_ei->flags);
1211
1212 if (exfat_free_cluster(new_inode, &new_clu_to_free)) {
1213 /* just set I/O error only */
1214 ret = -EIO;
1215 }
1216
1217 i_size_write(new_inode, 0);
1218 new_ei->valid_size = 0;
1219 new_ei->start_clu = EXFAT_EOF_CLUSTER;
1220 new_ei->flags = ALLOC_NO_FAT_CHAIN;
1221 }
1222del_out:
1223 /* Update new_inode ei
1224 * Prevent syncing removed new_inode
1225 * (new_ei is already initialized above code ("if (new_inode)")
1226 */
1227 new_ei->dir.dir = DIR_DELETED;
1228 }
1229out:
1230 return ret;
1231}
1232
1233static int exfat_rename(struct mnt_idmap *idmap,
1234 struct inode *old_dir, struct dentry *old_dentry,
1235 struct inode *new_dir, struct dentry *new_dentry,
1236 unsigned int flags)
1237{
1238 struct inode *old_inode, *new_inode;
1239 struct super_block *sb = old_dir->i_sb;
1240 loff_t i_pos;
1241 int err;
1242 loff_t size = i_size_read(new_dir);
1243
1244 /*
1245 * The VFS already checks for existence, so for local filesystems
1246 * the RENAME_NOREPLACE implementation is equivalent to plain rename.
1247 * Don't support any other flags
1248 */
1249 if (flags & ~RENAME_NOREPLACE)
1250 return -EINVAL;
1251
1252 mutex_lock(&EXFAT_SB(sb)->s_lock);
1253 old_inode = old_dentry->d_inode;
1254 new_inode = new_dentry->d_inode;
1255
1256 err = __exfat_rename(old_dir, EXFAT_I(old_inode), new_dir, new_dentry);
1257 if (err)
1258 goto unlock;
1259
1260 inode_inc_iversion(new_dir);
1261 simple_rename_timestamp(old_dir, old_dentry, new_dir, new_dentry);
1262 EXFAT_I(new_dir)->i_crtime = current_time(new_dir);
1263 exfat_truncate_inode_atime(new_dir);
1264 if (IS_DIRSYNC(new_dir) && size != i_size_read(new_dir))
1265 exfat_sync_inode(new_dir);
1266 else
1267 mark_inode_dirty(new_dir);
1268
1269 i_pos = ((loff_t)EXFAT_I(old_inode)->dir.dir << 32) |
1270 (EXFAT_I(old_inode)->entry & 0xffffffff);
1271 exfat_unhash_inode(old_inode);
1272 exfat_hash_inode(old_inode, i_pos);
1273 if (IS_DIRSYNC(new_dir))
1274 exfat_sync_inode(old_inode);
1275 else
1276 mark_inode_dirty(old_inode);
1277
1278 if (S_ISDIR(old_inode->i_mode) && old_dir != new_dir) {
1279 drop_nlink(old_dir);
1280 if (!new_inode)
1281 inc_nlink(new_dir);
1282 }
1283
1284 inode_inc_iversion(old_dir);
1285 if (new_dir != old_dir)
1286 mark_inode_dirty(old_dir);
1287
1288 if (new_inode) {
1289 exfat_unhash_inode(new_inode);
1290
1291 /* skip drop_nlink if new_inode already has been dropped */
1292 if (new_inode->i_nlink) {
1293 drop_nlink(new_inode);
1294 if (S_ISDIR(new_inode->i_mode))
1295 drop_nlink(new_inode);
1296 } else {
1297 exfat_warn(sb, "abnormal access to an inode dropped");
1298 WARN_ON(new_inode->i_nlink == 0);
1299 }
1300 EXFAT_I(new_inode)->i_crtime = current_time(new_inode);
1301 }
1302
1303unlock:
1304 mutex_unlock(&EXFAT_SB(sb)->s_lock);
1305 return err;
1306}
1307
1308const struct inode_operations exfat_dir_inode_operations = {
1309 .create = exfat_create,
1310 .lookup = exfat_lookup,
1311 .unlink = exfat_unlink,
1312 .mkdir = exfat_mkdir,
1313 .rmdir = exfat_rmdir,
1314 .rename = exfat_rename,
1315 .setattr = exfat_setattr,
1316 .getattr = exfat_getattr,
1317};
Linux 6.x block layer and io_uring tree(s)