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1// SPDX-License-Identifier: GPL-2.0-or-later
2/*
3 * Copyright (C) 2012-2013 Samsung Electronics Co., Ltd.
4 */
5
6#include <linux/slab.h>
7#include <linux/compat.h>
8#include <linux/cred.h>
9#include <linux/buffer_head.h>
10#include <linux/blkdev.h>
11#include <linux/fsnotify.h>
12#include <linux/security.h>
13#include <linux/msdos_fs.h>
14#include <linux/writeback.h>
15
16#include "exfat_raw.h"
17#include "exfat_fs.h"
18
19static int exfat_cont_expand(struct inode *inode, loff_t size)
20{
21 int ret;
22 unsigned int num_clusters, new_num_clusters, last_clu;
23 struct exfat_inode_info *ei = EXFAT_I(inode);
24 struct super_block *sb = inode->i_sb;
25 struct exfat_sb_info *sbi = EXFAT_SB(sb);
26 struct exfat_chain clu;
27
28 ret = inode_newsize_ok(inode, size);
29 if (ret)
30 return ret;
31
32 num_clusters = EXFAT_B_TO_CLU_ROUND_UP(ei->i_size_ondisk, sbi);
33 new_num_clusters = EXFAT_B_TO_CLU_ROUND_UP(size, sbi);
34
35 if (new_num_clusters == num_clusters)
36 goto out;
37
38 if (num_clusters) {
39 exfat_chain_set(&clu, ei->start_clu, num_clusters, ei->flags);
40 ret = exfat_find_last_cluster(sb, &clu, &last_clu);
41 if (ret)
42 return ret;
43
44 clu.dir = last_clu + 1;
45 } else {
46 last_clu = EXFAT_EOF_CLUSTER;
47 clu.dir = EXFAT_EOF_CLUSTER;
48 }
49
50 clu.size = 0;
51 clu.flags = ei->flags;
52
53 ret = exfat_alloc_cluster(inode, new_num_clusters - num_clusters,
54 &clu, inode_needs_sync(inode));
55 if (ret)
56 return ret;
57
58 /* Append new clusters to chain */
59 if (num_clusters) {
60 if (clu.flags != ei->flags)
61 if (exfat_chain_cont_cluster(sb, ei->start_clu, num_clusters))
62 goto free_clu;
63
64 if (clu.flags == ALLOC_FAT_CHAIN)
65 if (exfat_ent_set(sb, last_clu, clu.dir))
66 goto free_clu;
67 } else
68 ei->start_clu = clu.dir;
69
70 ei->flags = clu.flags;
71
72out:
73 inode_set_mtime_to_ts(inode, inode_set_ctime_current(inode));
74 /* Expanded range not zeroed, do not update valid_size */
75 i_size_write(inode, size);
76
77 ei->i_size_aligned = round_up(size, sb->s_blocksize);
78 ei->i_size_ondisk = ei->i_size_aligned;
79 inode->i_blocks = round_up(size, sbi->cluster_size) >> 9;
80 mark_inode_dirty(inode);
81
82 if (IS_SYNC(inode))
83 return write_inode_now(inode, 1);
84
85 return 0;
86
87free_clu:
88 exfat_free_cluster(inode, &clu);
89 return -EIO;
90}
91
92static bool exfat_allow_set_time(struct exfat_sb_info *sbi, struct inode *inode)
93{
94 mode_t allow_utime = sbi->options.allow_utime;
95
96 if (!uid_eq(current_fsuid(), inode->i_uid)) {
97 if (in_group_p(inode->i_gid))
98 allow_utime >>= 3;
99 if (allow_utime & MAY_WRITE)
100 return true;
101 }
102
103 /* use a default check */
104 return false;
105}
106
107static int exfat_sanitize_mode(const struct exfat_sb_info *sbi,
108 struct inode *inode, umode_t *mode_ptr)
109{
110 mode_t i_mode, mask, perm;
111
112 i_mode = inode->i_mode;
113
114 mask = (S_ISREG(i_mode) || S_ISLNK(i_mode)) ?
115 sbi->options.fs_fmask : sbi->options.fs_dmask;
116 perm = *mode_ptr & ~(S_IFMT | mask);
117
118 /* Of the r and x bits, all (subject to umask) must be present.*/
119 if ((perm & 0555) != (i_mode & 0555))
120 return -EPERM;
121
122 if (exfat_mode_can_hold_ro(inode)) {
123 /*
124 * Of the w bits, either all (subject to umask) or none must
125 * be present.
126 */
127 if ((perm & 0222) && ((perm & 0222) != (0222 & ~mask)))
128 return -EPERM;
129 } else {
130 /*
131 * If exfat_mode_can_hold_ro(inode) is false, can't change
132 * w bits.
133 */
134 if ((perm & 0222) != (0222 & ~mask))
135 return -EPERM;
136 }
137
138 *mode_ptr &= S_IFMT | perm;
139
140 return 0;
141}
142
143/* resize the file length */
144int __exfat_truncate(struct inode *inode)
145{
146 unsigned int num_clusters_new, num_clusters_phys;
147 unsigned int last_clu = EXFAT_FREE_CLUSTER;
148 struct exfat_chain clu;
149 struct super_block *sb = inode->i_sb;
150 struct exfat_sb_info *sbi = EXFAT_SB(sb);
151 struct exfat_inode_info *ei = EXFAT_I(inode);
152
153 /* check if the given file ID is opened */
154 if (ei->type != TYPE_FILE && ei->type != TYPE_DIR)
155 return -EPERM;
156
157 exfat_set_volume_dirty(sb);
158
159 num_clusters_new = EXFAT_B_TO_CLU_ROUND_UP(i_size_read(inode), sbi);
160 num_clusters_phys = EXFAT_B_TO_CLU_ROUND_UP(ei->i_size_ondisk, sbi);
161
162 exfat_chain_set(&clu, ei->start_clu, num_clusters_phys, ei->flags);
163
164 if (i_size_read(inode) > 0) {
165 /*
166 * Truncate FAT chain num_clusters after the first cluster
167 * num_clusters = min(new, phys);
168 */
169 unsigned int num_clusters =
170 min(num_clusters_new, num_clusters_phys);
171
172 /*
173 * Follow FAT chain
174 * (defensive coding - works fine even with corrupted FAT table
175 */
176 if (clu.flags == ALLOC_NO_FAT_CHAIN) {
177 clu.dir += num_clusters;
178 clu.size -= num_clusters;
179 } else {
180 while (num_clusters > 0) {
181 last_clu = clu.dir;
182 if (exfat_get_next_cluster(sb, &(clu.dir)))
183 return -EIO;
184
185 num_clusters--;
186 clu.size--;
187 }
188 }
189 } else {
190 ei->flags = ALLOC_NO_FAT_CHAIN;
191 ei->start_clu = EXFAT_EOF_CLUSTER;
192 }
193
194 if (i_size_read(inode) < ei->valid_size)
195 ei->valid_size = i_size_read(inode);
196
197 if (ei->type == TYPE_FILE)
198 ei->attr |= EXFAT_ATTR_ARCHIVE;
199
200 /*
201 * update the directory entry
202 *
203 * If the directory entry is updated by mark_inode_dirty(), the
204 * directory entry will be written after a writeback cycle of
205 * updating the bitmap/FAT, which may result in clusters being
206 * freed but referenced by the directory entry in the event of a
207 * sudden power failure.
208 * __exfat_write_inode() is called for directory entry, bitmap
209 * and FAT to be written in a same writeback.
210 */
211 if (__exfat_write_inode(inode, inode_needs_sync(inode)))
212 return -EIO;
213
214 /* cut off from the FAT chain */
215 if (ei->flags == ALLOC_FAT_CHAIN && last_clu != EXFAT_FREE_CLUSTER &&
216 last_clu != EXFAT_EOF_CLUSTER) {
217 if (exfat_ent_set(sb, last_clu, EXFAT_EOF_CLUSTER))
218 return -EIO;
219 }
220
221 /* invalidate cache and free the clusters */
222 /* clear exfat cache */
223 exfat_cache_inval_inode(inode);
224
225 /* hint information */
226 ei->hint_bmap.off = EXFAT_EOF_CLUSTER;
227 ei->hint_bmap.clu = EXFAT_EOF_CLUSTER;
228
229 /* hint_stat will be used if this is directory. */
230 ei->hint_stat.eidx = 0;
231 ei->hint_stat.clu = ei->start_clu;
232 ei->hint_femp.eidx = EXFAT_HINT_NONE;
233
234 /* free the clusters */
235 if (exfat_free_cluster(inode, &clu))
236 return -EIO;
237
238 return 0;
239}
240
241void exfat_truncate(struct inode *inode)
242{
243 struct super_block *sb = inode->i_sb;
244 struct exfat_sb_info *sbi = EXFAT_SB(sb);
245 struct exfat_inode_info *ei = EXFAT_I(inode);
246 unsigned int blocksize = i_blocksize(inode);
247 loff_t aligned_size;
248 int err;
249
250 mutex_lock(&sbi->s_lock);
251 if (ei->start_clu == 0) {
252 /*
253 * Empty start_clu != ~0 (not allocated)
254 */
255 exfat_fs_error(sb, "tried to truncate zeroed cluster.");
256 goto write_size;
257 }
258
259 err = __exfat_truncate(inode);
260 if (err)
261 goto write_size;
262
263 inode->i_blocks = round_up(i_size_read(inode), sbi->cluster_size) >> 9;
264write_size:
265 aligned_size = i_size_read(inode);
266 if (aligned_size & (blocksize - 1)) {
267 aligned_size |= (blocksize - 1);
268 aligned_size++;
269 }
270
271 if (ei->i_size_ondisk > i_size_read(inode))
272 ei->i_size_ondisk = aligned_size;
273
274 if (ei->i_size_aligned > i_size_read(inode))
275 ei->i_size_aligned = aligned_size;
276 mutex_unlock(&sbi->s_lock);
277}
278
279int exfat_getattr(struct mnt_idmap *idmap, const struct path *path,
280 struct kstat *stat, unsigned int request_mask,
281 unsigned int query_flags)
282{
283 struct inode *inode = d_backing_inode(path->dentry);
284 struct exfat_inode_info *ei = EXFAT_I(inode);
285
286 generic_fillattr(&nop_mnt_idmap, request_mask, inode, stat);
287 exfat_truncate_atime(&stat->atime);
288 stat->result_mask |= STATX_BTIME;
289 stat->btime.tv_sec = ei->i_crtime.tv_sec;
290 stat->btime.tv_nsec = ei->i_crtime.tv_nsec;
291 stat->blksize = EXFAT_SB(inode->i_sb)->cluster_size;
292 return 0;
293}
294
295int exfat_setattr(struct mnt_idmap *idmap, struct dentry *dentry,
296 struct iattr *attr)
297{
298 struct exfat_sb_info *sbi = EXFAT_SB(dentry->d_sb);
299 struct inode *inode = dentry->d_inode;
300 unsigned int ia_valid;
301 int error;
302
303 if ((attr->ia_valid & ATTR_SIZE) &&
304 attr->ia_size > i_size_read(inode)) {
305 error = exfat_cont_expand(inode, attr->ia_size);
306 if (error || attr->ia_valid == ATTR_SIZE)
307 return error;
308 attr->ia_valid &= ~ATTR_SIZE;
309 }
310
311 /* Check for setting the inode time. */
312 ia_valid = attr->ia_valid;
313 if ((ia_valid & (ATTR_MTIME_SET | ATTR_ATIME_SET | ATTR_TIMES_SET)) &&
314 exfat_allow_set_time(sbi, inode)) {
315 attr->ia_valid &= ~(ATTR_MTIME_SET | ATTR_ATIME_SET |
316 ATTR_TIMES_SET);
317 }
318
319 error = setattr_prepare(&nop_mnt_idmap, dentry, attr);
320 attr->ia_valid = ia_valid;
321 if (error)
322 goto out;
323
324 if (((attr->ia_valid & ATTR_UID) &&
325 !uid_eq(attr->ia_uid, sbi->options.fs_uid)) ||
326 ((attr->ia_valid & ATTR_GID) &&
327 !gid_eq(attr->ia_gid, sbi->options.fs_gid)) ||
328 ((attr->ia_valid & ATTR_MODE) &&
329 (attr->ia_mode & ~(S_IFREG | S_IFLNK | S_IFDIR | 0777)))) {
330 error = -EPERM;
331 goto out;
332 }
333
334 /*
335 * We don't return -EPERM here. Yes, strange, but this is too
336 * old behavior.
337 */
338 if (attr->ia_valid & ATTR_MODE) {
339 if (exfat_sanitize_mode(sbi, inode, &attr->ia_mode) < 0)
340 attr->ia_valid &= ~ATTR_MODE;
341 }
342
343 if (attr->ia_valid & ATTR_SIZE)
344 inode_set_mtime_to_ts(inode, inode_set_ctime_current(inode));
345
346 setattr_copy(&nop_mnt_idmap, inode, attr);
347 exfat_truncate_inode_atime(inode);
348
349 if (attr->ia_valid & ATTR_SIZE) {
350 error = exfat_block_truncate_page(inode, attr->ia_size);
351 if (error)
352 goto out;
353
354 down_write(&EXFAT_I(inode)->truncate_lock);
355 truncate_setsize(inode, attr->ia_size);
356
357 /*
358 * __exfat_write_inode() is called from exfat_truncate(), inode
359 * is already written by it, so mark_inode_dirty() is unneeded.
360 */
361 exfat_truncate(inode);
362 up_write(&EXFAT_I(inode)->truncate_lock);
363 } else
364 mark_inode_dirty(inode);
365
366out:
367 return error;
368}
369
370/*
371 * modified ioctls from fat/file.c by Welmer Almesberger
372 */
373static int exfat_ioctl_get_attributes(struct inode *inode, u32 __user *user_attr)
374{
375 u32 attr;
376
377 inode_lock_shared(inode);
378 attr = exfat_make_attr(inode);
379 inode_unlock_shared(inode);
380
381 return put_user(attr, user_attr);
382}
383
384static int exfat_ioctl_set_attributes(struct file *file, u32 __user *user_attr)
385{
386 struct inode *inode = file_inode(file);
387 struct exfat_sb_info *sbi = EXFAT_SB(inode->i_sb);
388 int is_dir = S_ISDIR(inode->i_mode);
389 u32 attr, oldattr;
390 struct iattr ia;
391 int err;
392
393 err = get_user(attr, user_attr);
394 if (err)
395 goto out;
396
397 err = mnt_want_write_file(file);
398 if (err)
399 goto out;
400 inode_lock(inode);
401
402 oldattr = exfat_make_attr(inode);
403
404 /*
405 * Mask attributes so we don't set reserved fields.
406 */
407 attr &= (EXFAT_ATTR_READONLY | EXFAT_ATTR_HIDDEN | EXFAT_ATTR_SYSTEM |
408 EXFAT_ATTR_ARCHIVE);
409 attr |= (is_dir ? EXFAT_ATTR_SUBDIR : 0);
410
411 /* Equivalent to a chmod() */
412 ia.ia_valid = ATTR_MODE | ATTR_CTIME;
413 ia.ia_ctime = current_time(inode);
414 if (is_dir)
415 ia.ia_mode = exfat_make_mode(sbi, attr, 0777);
416 else
417 ia.ia_mode = exfat_make_mode(sbi, attr, 0666 | (inode->i_mode & 0111));
418
419 /* The root directory has no attributes */
420 if (inode->i_ino == EXFAT_ROOT_INO && attr != EXFAT_ATTR_SUBDIR) {
421 err = -EINVAL;
422 goto out_unlock_inode;
423 }
424
425 if (((attr | oldattr) & EXFAT_ATTR_SYSTEM) &&
426 !capable(CAP_LINUX_IMMUTABLE)) {
427 err = -EPERM;
428 goto out_unlock_inode;
429 }
430
431 /*
432 * The security check is questionable... We single
433 * out the RO attribute for checking by the security
434 * module, just because it maps to a file mode.
435 */
436 err = security_inode_setattr(file_mnt_idmap(file),
437 file->f_path.dentry, &ia);
438 if (err)
439 goto out_unlock_inode;
440
441 /* This MUST be done before doing anything irreversible... */
442 err = exfat_setattr(file_mnt_idmap(file), file->f_path.dentry, &ia);
443 if (err)
444 goto out_unlock_inode;
445
446 fsnotify_change(file->f_path.dentry, ia.ia_valid);
447
448 exfat_save_attr(inode, attr);
449 mark_inode_dirty(inode);
450out_unlock_inode:
451 inode_unlock(inode);
452 mnt_drop_write_file(file);
453out:
454 return err;
455}
456
457static int exfat_ioctl_fitrim(struct inode *inode, unsigned long arg)
458{
459 struct fstrim_range range;
460 int ret = 0;
461
462 if (!capable(CAP_SYS_ADMIN))
463 return -EPERM;
464
465 if (!bdev_max_discard_sectors(inode->i_sb->s_bdev))
466 return -EOPNOTSUPP;
467
468 if (copy_from_user(&range, (struct fstrim_range __user *)arg, sizeof(range)))
469 return -EFAULT;
470
471 range.minlen = max_t(unsigned int, range.minlen,
472 bdev_discard_granularity(inode->i_sb->s_bdev));
473
474 ret = exfat_trim_fs(inode, &range);
475 if (ret < 0)
476 return ret;
477
478 if (copy_to_user((struct fstrim_range __user *)arg, &range, sizeof(range)))
479 return -EFAULT;
480
481 return 0;
482}
483
484long exfat_ioctl(struct file *filp, unsigned int cmd, unsigned long arg)
485{
486 struct inode *inode = file_inode(filp);
487 u32 __user *user_attr = (u32 __user *)arg;
488
489 switch (cmd) {
490 case FAT_IOCTL_GET_ATTRIBUTES:
491 return exfat_ioctl_get_attributes(inode, user_attr);
492 case FAT_IOCTL_SET_ATTRIBUTES:
493 return exfat_ioctl_set_attributes(filp, user_attr);
494 case FITRIM:
495 return exfat_ioctl_fitrim(inode, arg);
496 default:
497 return -ENOTTY;
498 }
499}
500
501#ifdef CONFIG_COMPAT
502long exfat_compat_ioctl(struct file *filp, unsigned int cmd,
503 unsigned long arg)
504{
505 return exfat_ioctl(filp, cmd, (unsigned long)compat_ptr(arg));
506}
507#endif
508
509int exfat_file_fsync(struct file *filp, loff_t start, loff_t end, int datasync)
510{
511 struct inode *inode = filp->f_mapping->host;
512 int err;
513
514 err = __generic_file_fsync(filp, start, end, datasync);
515 if (err)
516 return err;
517
518 err = sync_blockdev(inode->i_sb->s_bdev);
519 if (err)
520 return err;
521
522 return blkdev_issue_flush(inode->i_sb->s_bdev);
523}
524
525static int exfat_file_zeroed_range(struct file *file, loff_t start, loff_t end)
526{
527 int err;
528 struct inode *inode = file_inode(file);
529 struct address_space *mapping = inode->i_mapping;
530 const struct address_space_operations *ops = mapping->a_ops;
531
532 while (start < end) {
533 u32 zerofrom, len;
534 struct page *page = NULL;
535
536 zerofrom = start & (PAGE_SIZE - 1);
537 len = PAGE_SIZE - zerofrom;
538 if (start + len > end)
539 len = end - start;
540
541 err = ops->write_begin(file, mapping, start, len, &page, NULL);
542 if (err)
543 goto out;
544
545 zero_user_segment(page, zerofrom, zerofrom + len);
546
547 err = ops->write_end(file, mapping, start, len, len, page, NULL);
548 if (err < 0)
549 goto out;
550 start += len;
551
552 balance_dirty_pages_ratelimited(mapping);
553 cond_resched();
554 }
555
556out:
557 return err;
558}
559
560static ssize_t exfat_file_write_iter(struct kiocb *iocb, struct iov_iter *iter)
561{
562 ssize_t ret;
563 struct file *file = iocb->ki_filp;
564 struct inode *inode = file_inode(file);
565 struct exfat_inode_info *ei = EXFAT_I(inode);
566 loff_t pos = iocb->ki_pos;
567 loff_t valid_size;
568
569 inode_lock(inode);
570
571 valid_size = ei->valid_size;
572
573 ret = generic_write_checks(iocb, iter);
574 if (ret < 0)
575 goto unlock;
576
577 if (pos > valid_size) {
578 ret = exfat_file_zeroed_range(file, valid_size, pos);
579 if (ret < 0 && ret != -ENOSPC) {
580 exfat_err(inode->i_sb,
581 "write: fail to zero from %llu to %llu(%zd)",
582 valid_size, pos, ret);
583 }
584 if (ret < 0)
585 goto unlock;
586 }
587
588 ret = __generic_file_write_iter(iocb, iter);
589 if (ret < 0)
590 goto unlock;
591
592 inode_unlock(inode);
593
594 if (pos > valid_size)
595 pos = valid_size;
596
597 if (iocb_is_dsync(iocb) && iocb->ki_pos > pos) {
598 ssize_t err = vfs_fsync_range(file, pos, iocb->ki_pos - 1,
599 iocb->ki_flags & IOCB_SYNC);
600 if (err < 0)
601 return err;
602 }
603
604 return ret;
605
606unlock:
607 inode_unlock(inode);
608
609 return ret;
610}
611
612static int exfat_file_mmap(struct file *file, struct vm_area_struct *vma)
613{
614 int ret;
615 struct inode *inode = file_inode(file);
616 struct exfat_inode_info *ei = EXFAT_I(inode);
617 loff_t start = ((loff_t)vma->vm_pgoff << PAGE_SHIFT);
618 loff_t end = min_t(loff_t, i_size_read(inode),
619 start + vma->vm_end - vma->vm_start);
620
621 if ((vma->vm_flags & VM_WRITE) && ei->valid_size < end) {
622 ret = exfat_file_zeroed_range(file, ei->valid_size, end);
623 if (ret < 0) {
624 exfat_err(inode->i_sb,
625 "mmap: fail to zero from %llu to %llu(%d)",
626 start, end, ret);
627 return ret;
628 }
629 }
630
631 return generic_file_mmap(file, vma);
632}
633
634const struct file_operations exfat_file_operations = {
635 .llseek = generic_file_llseek,
636 .read_iter = generic_file_read_iter,
637 .write_iter = exfat_file_write_iter,
638 .unlocked_ioctl = exfat_ioctl,
639#ifdef CONFIG_COMPAT
640 .compat_ioctl = exfat_compat_ioctl,
641#endif
642 .mmap = exfat_file_mmap,
643 .fsync = exfat_file_fsync,
644 .splice_read = filemap_splice_read,
645 .splice_write = iter_file_splice_write,
646};
647
648const struct inode_operations exfat_file_inode_operations = {
649 .setattr = exfat_setattr,
650 .getattr = exfat_getattr,
651};
1// SPDX-License-Identifier: GPL-2.0-or-later
2/*
3 * Copyright (C) 2012-2013 Samsung Electronics Co., Ltd.
4 */
5
6#include <linux/slab.h>
7#include <linux/cred.h>
8#include <linux/buffer_head.h>
9#include <linux/blkdev.h>
10
11#include "exfat_raw.h"
12#include "exfat_fs.h"
13
14static int exfat_cont_expand(struct inode *inode, loff_t size)
15{
16 struct address_space *mapping = inode->i_mapping;
17 loff_t start = i_size_read(inode), count = size - i_size_read(inode);
18 int err, err2;
19
20 err = generic_cont_expand_simple(inode, size);
21 if (err)
22 return err;
23
24 inode->i_ctime = inode->i_mtime = current_time(inode);
25 mark_inode_dirty(inode);
26
27 if (!IS_SYNC(inode))
28 return 0;
29
30 err = filemap_fdatawrite_range(mapping, start, start + count - 1);
31 err2 = sync_mapping_buffers(mapping);
32 if (!err)
33 err = err2;
34 err2 = write_inode_now(inode, 1);
35 if (!err)
36 err = err2;
37 if (err)
38 return err;
39
40 return filemap_fdatawait_range(mapping, start, start + count - 1);
41}
42
43static bool exfat_allow_set_time(struct exfat_sb_info *sbi, struct inode *inode)
44{
45 mode_t allow_utime = sbi->options.allow_utime;
46
47 if (!uid_eq(current_fsuid(), inode->i_uid)) {
48 if (in_group_p(inode->i_gid))
49 allow_utime >>= 3;
50 if (allow_utime & MAY_WRITE)
51 return true;
52 }
53
54 /* use a default check */
55 return false;
56}
57
58static int exfat_sanitize_mode(const struct exfat_sb_info *sbi,
59 struct inode *inode, umode_t *mode_ptr)
60{
61 mode_t i_mode, mask, perm;
62
63 i_mode = inode->i_mode;
64
65 mask = (S_ISREG(i_mode) || S_ISLNK(i_mode)) ?
66 sbi->options.fs_fmask : sbi->options.fs_dmask;
67 perm = *mode_ptr & ~(S_IFMT | mask);
68
69 /* Of the r and x bits, all (subject to umask) must be present.*/
70 if ((perm & 0555) != (i_mode & 0555))
71 return -EPERM;
72
73 if (exfat_mode_can_hold_ro(inode)) {
74 /*
75 * Of the w bits, either all (subject to umask) or none must
76 * be present.
77 */
78 if ((perm & 0222) && ((perm & 0222) != (0222 & ~mask)))
79 return -EPERM;
80 } else {
81 /*
82 * If exfat_mode_can_hold_ro(inode) is false, can't change
83 * w bits.
84 */
85 if ((perm & 0222) != (0222 & ~mask))
86 return -EPERM;
87 }
88
89 *mode_ptr &= S_IFMT | perm;
90
91 return 0;
92}
93
94/* resize the file length */
95int __exfat_truncate(struct inode *inode, loff_t new_size)
96{
97 unsigned int num_clusters_new, num_clusters_phys;
98 unsigned int last_clu = EXFAT_FREE_CLUSTER;
99 struct exfat_chain clu;
100 struct super_block *sb = inode->i_sb;
101 struct exfat_sb_info *sbi = EXFAT_SB(sb);
102 struct exfat_inode_info *ei = EXFAT_I(inode);
103 int evict = (ei->dir.dir == DIR_DELETED) ? 1 : 0;
104
105 /* check if the given file ID is opened */
106 if (ei->type != TYPE_FILE && ei->type != TYPE_DIR)
107 return -EPERM;
108
109 exfat_set_volume_dirty(sb);
110
111 num_clusters_new = EXFAT_B_TO_CLU_ROUND_UP(i_size_read(inode), sbi);
112 num_clusters_phys =
113 EXFAT_B_TO_CLU_ROUND_UP(EXFAT_I(inode)->i_size_ondisk, sbi);
114
115 exfat_chain_set(&clu, ei->start_clu, num_clusters_phys, ei->flags);
116
117 if (new_size > 0) {
118 /*
119 * Truncate FAT chain num_clusters after the first cluster
120 * num_clusters = min(new, phys);
121 */
122 unsigned int num_clusters =
123 min(num_clusters_new, num_clusters_phys);
124
125 /*
126 * Follow FAT chain
127 * (defensive coding - works fine even with corrupted FAT table
128 */
129 if (clu.flags == ALLOC_NO_FAT_CHAIN) {
130 clu.dir += num_clusters;
131 clu.size -= num_clusters;
132 } else {
133 while (num_clusters > 0) {
134 last_clu = clu.dir;
135 if (exfat_get_next_cluster(sb, &(clu.dir)))
136 return -EIO;
137
138 num_clusters--;
139 clu.size--;
140 }
141 }
142 } else {
143 ei->flags = ALLOC_NO_FAT_CHAIN;
144 ei->start_clu = EXFAT_EOF_CLUSTER;
145 }
146
147 i_size_write(inode, new_size);
148
149 if (ei->type == TYPE_FILE)
150 ei->attr |= ATTR_ARCHIVE;
151
152 /* update the directory entry */
153 if (!evict) {
154 struct timespec64 ts;
155 struct exfat_dentry *ep, *ep2;
156 struct exfat_entry_set_cache *es;
157 int err;
158
159 es = exfat_get_dentry_set(sb, &(ei->dir), ei->entry,
160 ES_ALL_ENTRIES);
161 if (!es)
162 return -EIO;
163 ep = exfat_get_dentry_cached(es, 0);
164 ep2 = exfat_get_dentry_cached(es, 1);
165
166 ts = current_time(inode);
167 exfat_set_entry_time(sbi, &ts,
168 &ep->dentry.file.modify_tz,
169 &ep->dentry.file.modify_time,
170 &ep->dentry.file.modify_date,
171 &ep->dentry.file.modify_time_cs);
172 ep->dentry.file.attr = cpu_to_le16(ei->attr);
173
174 /* File size should be zero if there is no cluster allocated */
175 if (ei->start_clu == EXFAT_EOF_CLUSTER) {
176 ep2->dentry.stream.valid_size = 0;
177 ep2->dentry.stream.size = 0;
178 } else {
179 ep2->dentry.stream.valid_size = cpu_to_le64(new_size);
180 ep2->dentry.stream.size = ep2->dentry.stream.valid_size;
181 }
182
183 if (new_size == 0) {
184 /* Any directory can not be truncated to zero */
185 WARN_ON(ei->type != TYPE_FILE);
186
187 ep2->dentry.stream.flags = ALLOC_FAT_CHAIN;
188 ep2->dentry.stream.start_clu = EXFAT_FREE_CLUSTER;
189 }
190
191 exfat_update_dir_chksum_with_entry_set(es);
192 err = exfat_free_dentry_set(es, inode_needs_sync(inode));
193 if (err)
194 return err;
195 }
196
197 /* cut off from the FAT chain */
198 if (ei->flags == ALLOC_FAT_CHAIN && last_clu != EXFAT_FREE_CLUSTER &&
199 last_clu != EXFAT_EOF_CLUSTER) {
200 if (exfat_ent_set(sb, last_clu, EXFAT_EOF_CLUSTER))
201 return -EIO;
202 }
203
204 /* invalidate cache and free the clusters */
205 /* clear exfat cache */
206 exfat_cache_inval_inode(inode);
207
208 /* hint information */
209 ei->hint_bmap.off = EXFAT_EOF_CLUSTER;
210 ei->hint_bmap.clu = EXFAT_EOF_CLUSTER;
211 if (ei->rwoffset > new_size)
212 ei->rwoffset = new_size;
213
214 /* hint_stat will be used if this is directory. */
215 ei->hint_stat.eidx = 0;
216 ei->hint_stat.clu = ei->start_clu;
217 ei->hint_femp.eidx = EXFAT_HINT_NONE;
218
219 /* free the clusters */
220 if (exfat_free_cluster(inode, &clu))
221 return -EIO;
222
223 exfat_clear_volume_dirty(sb);
224
225 return 0;
226}
227
228void exfat_truncate(struct inode *inode, loff_t size)
229{
230 struct super_block *sb = inode->i_sb;
231 struct exfat_sb_info *sbi = EXFAT_SB(sb);
232 unsigned int blocksize = 1 << inode->i_blkbits;
233 loff_t aligned_size;
234 int err;
235
236 mutex_lock(&sbi->s_lock);
237 if (EXFAT_I(inode)->start_clu == 0) {
238 /*
239 * Empty start_clu != ~0 (not allocated)
240 */
241 exfat_fs_error(sb, "tried to truncate zeroed cluster.");
242 goto write_size;
243 }
244
245 err = __exfat_truncate(inode, i_size_read(inode));
246 if (err)
247 goto write_size;
248
249 inode->i_ctime = inode->i_mtime = current_time(inode);
250 if (IS_DIRSYNC(inode))
251 exfat_sync_inode(inode);
252 else
253 mark_inode_dirty(inode);
254
255 inode->i_blocks = ((i_size_read(inode) + (sbi->cluster_size - 1)) &
256 ~(sbi->cluster_size - 1)) >> inode->i_blkbits;
257write_size:
258 aligned_size = i_size_read(inode);
259 if (aligned_size & (blocksize - 1)) {
260 aligned_size |= (blocksize - 1);
261 aligned_size++;
262 }
263
264 if (EXFAT_I(inode)->i_size_ondisk > i_size_read(inode))
265 EXFAT_I(inode)->i_size_ondisk = aligned_size;
266
267 if (EXFAT_I(inode)->i_size_aligned > i_size_read(inode))
268 EXFAT_I(inode)->i_size_aligned = aligned_size;
269 mutex_unlock(&sbi->s_lock);
270}
271
272int exfat_getattr(const struct path *path, struct kstat *stat,
273 unsigned int request_mask, unsigned int query_flags)
274{
275 struct inode *inode = d_backing_inode(path->dentry);
276 struct exfat_inode_info *ei = EXFAT_I(inode);
277
278 generic_fillattr(inode, stat);
279 exfat_truncate_atime(&stat->atime);
280 stat->result_mask |= STATX_BTIME;
281 stat->btime.tv_sec = ei->i_crtime.tv_sec;
282 stat->btime.tv_nsec = ei->i_crtime.tv_nsec;
283 stat->blksize = EXFAT_SB(inode->i_sb)->cluster_size;
284 return 0;
285}
286
287int exfat_setattr(struct dentry *dentry, struct iattr *attr)
288{
289 struct exfat_sb_info *sbi = EXFAT_SB(dentry->d_sb);
290 struct inode *inode = dentry->d_inode;
291 unsigned int ia_valid;
292 int error;
293
294 if ((attr->ia_valid & ATTR_SIZE) &&
295 attr->ia_size > i_size_read(inode)) {
296 error = exfat_cont_expand(inode, attr->ia_size);
297 if (error || attr->ia_valid == ATTR_SIZE)
298 return error;
299 attr->ia_valid &= ~ATTR_SIZE;
300 }
301
302 /* Check for setting the inode time. */
303 ia_valid = attr->ia_valid;
304 if ((ia_valid & (ATTR_MTIME_SET | ATTR_ATIME_SET | ATTR_TIMES_SET)) &&
305 exfat_allow_set_time(sbi, inode)) {
306 attr->ia_valid &= ~(ATTR_MTIME_SET | ATTR_ATIME_SET |
307 ATTR_TIMES_SET);
308 }
309
310 error = setattr_prepare(dentry, attr);
311 attr->ia_valid = ia_valid;
312 if (error)
313 goto out;
314
315 if (((attr->ia_valid & ATTR_UID) &&
316 !uid_eq(attr->ia_uid, sbi->options.fs_uid)) ||
317 ((attr->ia_valid & ATTR_GID) &&
318 !gid_eq(attr->ia_gid, sbi->options.fs_gid)) ||
319 ((attr->ia_valid & ATTR_MODE) &&
320 (attr->ia_mode & ~(S_IFREG | S_IFLNK | S_IFDIR | 0777)))) {
321 error = -EPERM;
322 goto out;
323 }
324
325 /*
326 * We don't return -EPERM here. Yes, strange, but this is too
327 * old behavior.
328 */
329 if (attr->ia_valid & ATTR_MODE) {
330 if (exfat_sanitize_mode(sbi, inode, &attr->ia_mode) < 0)
331 attr->ia_valid &= ~ATTR_MODE;
332 }
333
334 if (attr->ia_valid & ATTR_SIZE) {
335 error = exfat_block_truncate_page(inode, attr->ia_size);
336 if (error)
337 goto out;
338
339 down_write(&EXFAT_I(inode)->truncate_lock);
340 truncate_setsize(inode, attr->ia_size);
341 exfat_truncate(inode, attr->ia_size);
342 up_write(&EXFAT_I(inode)->truncate_lock);
343 }
344
345 setattr_copy(inode, attr);
346 exfat_truncate_atime(&inode->i_atime);
347 mark_inode_dirty(inode);
348
349out:
350 return error;
351}
352
353int exfat_file_fsync(struct file *filp, loff_t start, loff_t end, int datasync)
354{
355 struct inode *inode = filp->f_mapping->host;
356 int err;
357
358 err = __generic_file_fsync(filp, start, end, datasync);
359 if (err)
360 return err;
361
362 err = sync_blockdev(inode->i_sb->s_bdev);
363 if (err)
364 return err;
365
366 return blkdev_issue_flush(inode->i_sb->s_bdev, GFP_KERNEL);
367}
368
369const struct file_operations exfat_file_operations = {
370 .llseek = generic_file_llseek,
371 .read_iter = generic_file_read_iter,
372 .write_iter = generic_file_write_iter,
373 .mmap = generic_file_mmap,
374 .fsync = exfat_file_fsync,
375 .splice_read = generic_file_splice_read,
376 .splice_write = iter_file_splice_write,
377};
378
379const struct inode_operations exfat_file_inode_operations = {
380 .setattr = exfat_setattr,
381 .getattr = exfat_getattr,
382};