xref: /linux/fs/ntfs3/inode.c (revision 300a90b2cb5d442879e6398920c49aebbd5c8e40)
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  *
4  * Copyright (C) 2019-2021 Paragon Software GmbH, All rights reserved.
5  *
6  */
7 
8 #include <linux/buffer_head.h>
9 #include <linux/fs.h>
10 #include <linux/mpage.h>
11 #include <linux/namei.h>
12 #include <linux/nls.h>
13 #include <linux/uio.h>
14 #include <linux/writeback.h>
15 
16 #include "debug.h"
17 #include "ntfs.h"
18 #include "ntfs_fs.h"
19 
20 /*
21  * ntfs_read_mft - Read record and parse MFT.
22  */
23 static struct inode *ntfs_read_mft(struct inode *inode,
24 				   const struct cpu_str *name,
25 				   const struct MFT_REF *ref)
26 {
27 	int err = 0;
28 	struct ntfs_inode *ni = ntfs_i(inode);
29 	struct super_block *sb = inode->i_sb;
30 	struct ntfs_sb_info *sbi = sb->s_fs_info;
31 	mode_t mode = 0;
32 	struct ATTR_STD_INFO5 *std5 = NULL;
33 	struct ATTR_LIST_ENTRY *le;
34 	struct ATTRIB *attr;
35 	bool is_match = false;
36 	bool is_root = false;
37 	bool is_dir;
38 	unsigned long ino = inode->i_ino;
39 	u32 rp_fa = 0, asize, t32;
40 	u16 roff, rsize, names = 0, links = 0;
41 	const struct ATTR_FILE_NAME *fname = NULL;
42 	const struct INDEX_ROOT *root;
43 	struct REPARSE_DATA_BUFFER rp; // 0x18 bytes
44 	u64 t64;
45 	struct MFT_REC *rec;
46 	struct runs_tree *run;
47 	struct timespec64 ts;
48 
49 	inode->i_op = NULL;
50 	/* Setup 'uid' and 'gid' */
51 	inode->i_uid = sbi->options->fs_uid;
52 	inode->i_gid = sbi->options->fs_gid;
53 
54 	err = mi_init(&ni->mi, sbi, ino);
55 	if (err)
56 		goto out;
57 
58 	if (!sbi->mft.ni && ino == MFT_REC_MFT && !sb->s_root) {
59 		t64 = sbi->mft.lbo >> sbi->cluster_bits;
60 		t32 = bytes_to_cluster(sbi, MFT_REC_VOL * sbi->record_size);
61 		sbi->mft.ni = ni;
62 		init_rwsem(&ni->file.run_lock);
63 
64 		if (!run_add_entry(&ni->file.run, 0, t64, t32, true)) {
65 			err = -ENOMEM;
66 			goto out;
67 		}
68 	}
69 
70 	err = mi_read(&ni->mi, ino == MFT_REC_MFT);
71 
72 	if (err)
73 		goto out;
74 
75 	rec = ni->mi.mrec;
76 
77 	if (sbi->flags & NTFS_FLAGS_LOG_REPLAYING) {
78 		;
79 	} else if (ref->seq != rec->seq) {
80 		err = -EINVAL;
81 		ntfs_err(sb, "MFT: r=%lx, expect seq=%x instead of %x!", ino,
82 			 le16_to_cpu(ref->seq), le16_to_cpu(rec->seq));
83 		goto out;
84 	} else if (!is_rec_inuse(rec)) {
85 		err = -ESTALE;
86 		ntfs_err(sb, "Inode r=%x is not in use!", (u32)ino);
87 		goto out;
88 	}
89 
90 	if (le32_to_cpu(rec->total) != sbi->record_size) {
91 		/* Bad inode? */
92 		err = -EINVAL;
93 		goto out;
94 	}
95 
96 	if (!is_rec_base(rec)) {
97 		err = -EINVAL;
98 		goto out;
99 	}
100 
101 	/* Record should contain $I30 root. */
102 	is_dir = rec->flags & RECORD_FLAG_DIR;
103 
104 	/* MFT_REC_MFT is not a dir */
105 	if (is_dir && ino == MFT_REC_MFT) {
106 		err = -EINVAL;
107 		goto out;
108 	}
109 
110 	inode->i_generation = le16_to_cpu(rec->seq);
111 
112 	/* Enumerate all struct Attributes MFT. */
113 	le = NULL;
114 	attr = NULL;
115 
116 	/*
117 	 * To reduce tab pressure use goto instead of
118 	 * while( (attr = ni_enum_attr_ex(ni, attr, &le, NULL) ))
119 	 */
120 next_attr:
121 	run = NULL;
122 	err = -EINVAL;
123 	attr = ni_enum_attr_ex(ni, attr, &le, NULL);
124 	if (!attr)
125 		goto end_enum;
126 
127 	if (le && le->vcn) {
128 		/* This is non primary attribute segment. Ignore if not MFT. */
129 		if (ino != MFT_REC_MFT || attr->type != ATTR_DATA)
130 			goto next_attr;
131 
132 		run = &ni->file.run;
133 		asize = le32_to_cpu(attr->size);
134 		goto attr_unpack_run;
135 	}
136 
137 	roff = attr->non_res ? 0 : le16_to_cpu(attr->res.data_off);
138 	rsize = attr->non_res ? 0 : le32_to_cpu(attr->res.data_size);
139 	asize = le32_to_cpu(attr->size);
140 
141 	/*
142 	 * Really this check was done in 'ni_enum_attr_ex' -> ... 'mi_enum_attr'.
143 	 * There not critical to check this case again
144 	 */
145 	if (attr->name_len &&
146 	    sizeof(short) * attr->name_len + le16_to_cpu(attr->name_off) >
147 		    asize)
148 		goto out;
149 
150 	if (attr->non_res) {
151 		t64 = le64_to_cpu(attr->nres.alloc_size);
152 		if (le64_to_cpu(attr->nres.data_size) > t64 ||
153 		    le64_to_cpu(attr->nres.valid_size) > t64)
154 			goto out;
155 	}
156 
157 	switch (attr->type) {
158 	case ATTR_STD:
159 		if (attr->non_res ||
160 		    asize < sizeof(struct ATTR_STD_INFO) + roff ||
161 		    rsize < sizeof(struct ATTR_STD_INFO))
162 			goto out;
163 
164 		if (std5)
165 			goto next_attr;
166 
167 		std5 = Add2Ptr(attr, roff);
168 
169 #ifdef STATX_BTIME
170 		nt2kernel(std5->cr_time, &ni->i_crtime);
171 #endif
172 		nt2kernel(std5->a_time, &ts);
173 		inode_set_atime_to_ts(inode, ts);
174 		nt2kernel(std5->c_time, &ts);
175 		inode_set_ctime_to_ts(inode, ts);
176 		nt2kernel(std5->m_time, &ts);
177 		inode_set_mtime_to_ts(inode, ts);
178 
179 		ni->std_fa = std5->fa;
180 
181 		if (asize >= sizeof(struct ATTR_STD_INFO5) + roff &&
182 		    rsize >= sizeof(struct ATTR_STD_INFO5))
183 			ni->std_security_id = std5->security_id;
184 		goto next_attr;
185 
186 	case ATTR_LIST:
187 		if (attr->name_len || le || ino == MFT_REC_LOG)
188 			goto out;
189 
190 		err = ntfs_load_attr_list(ni, attr);
191 		if (err)
192 			goto out;
193 
194 		le = NULL;
195 		attr = NULL;
196 		goto next_attr;
197 
198 	case ATTR_NAME:
199 		if (attr->non_res || asize < SIZEOF_ATTRIBUTE_FILENAME + roff ||
200 		    rsize < SIZEOF_ATTRIBUTE_FILENAME)
201 			goto out;
202 
203 		names += 1;
204 		fname = Add2Ptr(attr, roff);
205 		if (fname->type == FILE_NAME_DOS)
206 			goto next_attr;
207 
208 		links += 1;
209 		if (name && name->len == fname->name_len &&
210 		    !ntfs_cmp_names_cpu(name, (struct le_str *)&fname->name_len,
211 					NULL, false))
212 			is_match = true;
213 
214 		goto next_attr;
215 
216 	case ATTR_DATA:
217 		if (is_dir) {
218 			/* Ignore data attribute in dir record. */
219 			goto next_attr;
220 		}
221 
222 		if (ino == MFT_REC_BADCLUST && !attr->non_res)
223 			goto next_attr;
224 
225 		if (attr->name_len &&
226 		    ((ino != MFT_REC_BADCLUST || !attr->non_res ||
227 		      attr->name_len != ARRAY_SIZE(BAD_NAME) ||
228 		      memcmp(attr_name(attr), BAD_NAME, sizeof(BAD_NAME))) &&
229 		     (ino != MFT_REC_SECURE || !attr->non_res ||
230 		      attr->name_len != ARRAY_SIZE(SDS_NAME) ||
231 		      memcmp(attr_name(attr), SDS_NAME, sizeof(SDS_NAME))))) {
232 			/* File contains stream attribute. Ignore it. */
233 			goto next_attr;
234 		}
235 
236 		if (is_attr_sparsed(attr))
237 			ni->std_fa |= FILE_ATTRIBUTE_SPARSE_FILE;
238 		else
239 			ni->std_fa &= ~FILE_ATTRIBUTE_SPARSE_FILE;
240 
241 		if (is_attr_compressed(attr))
242 			ni->std_fa |= FILE_ATTRIBUTE_COMPRESSED;
243 		else
244 			ni->std_fa &= ~FILE_ATTRIBUTE_COMPRESSED;
245 
246 		if (is_attr_encrypted(attr))
247 			ni->std_fa |= FILE_ATTRIBUTE_ENCRYPTED;
248 		else
249 			ni->std_fa &= ~FILE_ATTRIBUTE_ENCRYPTED;
250 
251 		if (!attr->non_res) {
252 			ni->i_valid = inode->i_size = rsize;
253 			inode_set_bytes(inode, rsize);
254 		}
255 
256 		mode = S_IFREG | (0777 & sbi->options->fs_fmask_inv);
257 
258 		if (!attr->non_res) {
259 			ni->ni_flags |= NI_FLAG_RESIDENT;
260 			goto next_attr;
261 		}
262 
263 		inode_set_bytes(inode, attr_ondisk_size(attr));
264 
265 		ni->i_valid = le64_to_cpu(attr->nres.valid_size);
266 		inode->i_size = le64_to_cpu(attr->nres.data_size);
267 		if (!attr->nres.alloc_size)
268 			goto next_attr;
269 
270 		run = ino == MFT_REC_BITMAP ? &sbi->used.bitmap.run :
271 					      &ni->file.run;
272 		break;
273 
274 	case ATTR_ROOT:
275 		if (attr->non_res)
276 			goto out;
277 
278 		root = Add2Ptr(attr, roff);
279 
280 		if (attr->name_len != ARRAY_SIZE(I30_NAME) ||
281 		    memcmp(attr_name(attr), I30_NAME, sizeof(I30_NAME)))
282 			goto next_attr;
283 
284 		if (root->type != ATTR_NAME ||
285 		    root->rule != NTFS_COLLATION_TYPE_FILENAME)
286 			goto out;
287 
288 		if (!is_dir)
289 			goto next_attr;
290 
291 		is_root = true;
292 		ni->ni_flags |= NI_FLAG_DIR;
293 
294 		err = indx_init(&ni->dir, sbi, attr, INDEX_MUTEX_I30);
295 		if (err)
296 			goto out;
297 
298 		mode = sb->s_root ?
299 			       (S_IFDIR | (0777 & sbi->options->fs_dmask_inv)) :
300 			       (S_IFDIR | 0777);
301 		goto next_attr;
302 
303 	case ATTR_ALLOC:
304 		if (!is_root || attr->name_len != ARRAY_SIZE(I30_NAME) ||
305 		    memcmp(attr_name(attr), I30_NAME, sizeof(I30_NAME)))
306 			goto next_attr;
307 
308 		inode->i_size = le64_to_cpu(attr->nres.data_size);
309 		ni->i_valid = le64_to_cpu(attr->nres.valid_size);
310 		inode_set_bytes(inode, le64_to_cpu(attr->nres.alloc_size));
311 
312 		run = &ni->dir.alloc_run;
313 		break;
314 
315 	case ATTR_BITMAP:
316 		if (ino == MFT_REC_MFT) {
317 			if (!attr->non_res)
318 				goto out;
319 #ifndef CONFIG_NTFS3_64BIT_CLUSTER
320 			/* 0x20000000 = 2^32 / 8 */
321 			if (le64_to_cpu(attr->nres.alloc_size) >= 0x20000000)
322 				goto out;
323 #endif
324 			run = &sbi->mft.bitmap.run;
325 			break;
326 		} else if (is_dir && attr->name_len == ARRAY_SIZE(I30_NAME) &&
327 			   !memcmp(attr_name(attr), I30_NAME,
328 				   sizeof(I30_NAME)) &&
329 			   attr->non_res) {
330 			run = &ni->dir.bitmap_run;
331 			break;
332 		}
333 		goto next_attr;
334 
335 	case ATTR_REPARSE:
336 		if (attr->name_len)
337 			goto next_attr;
338 
339 		rp_fa = ni_parse_reparse(ni, attr, &rp);
340 		switch (rp_fa) {
341 		case REPARSE_LINK:
342 			/*
343 			 * Normal symlink.
344 			 * Assume one unicode symbol == one utf8.
345 			 */
346 			inode->i_size = le16_to_cpu(rp.SymbolicLinkReparseBuffer
347 							    .PrintNameLength) /
348 					sizeof(u16);
349 			ni->i_valid = inode->i_size;
350 			/* Clear directory bit. */
351 			if (ni->ni_flags & NI_FLAG_DIR) {
352 				indx_clear(&ni->dir);
353 				memset(&ni->dir, 0, sizeof(ni->dir));
354 				ni->ni_flags &= ~NI_FLAG_DIR;
355 			} else {
356 				run_close(&ni->file.run);
357 			}
358 			mode = S_IFLNK | 0777;
359 			is_dir = false;
360 			if (attr->non_res) {
361 				run = &ni->file.run;
362 				goto attr_unpack_run; // Double break.
363 			}
364 			break;
365 
366 		case REPARSE_COMPRESSED:
367 			break;
368 
369 		case REPARSE_DEDUPLICATED:
370 			break;
371 		}
372 		goto next_attr;
373 
374 	case ATTR_EA_INFO:
375 		if (!attr->name_len &&
376 		    resident_data_ex(attr, sizeof(struct EA_INFO))) {
377 			ni->ni_flags |= NI_FLAG_EA;
378 			/*
379 			 * ntfs_get_wsl_perm updates inode->i_uid, inode->i_gid, inode->i_mode
380 			 */
381 			inode->i_mode = mode;
382 			ntfs_get_wsl_perm(inode);
383 			mode = inode->i_mode;
384 		}
385 		goto next_attr;
386 
387 	default:
388 		goto next_attr;
389 	}
390 
391 attr_unpack_run:
392 	roff = le16_to_cpu(attr->nres.run_off);
393 
394 	if (roff > asize) {
395 		err = -EINVAL;
396 		goto out;
397 	}
398 
399 	t64 = le64_to_cpu(attr->nres.svcn);
400 
401 	err = run_unpack_ex(run, sbi, ino, t64, le64_to_cpu(attr->nres.evcn),
402 			    t64, Add2Ptr(attr, roff), asize - roff);
403 	if (err < 0)
404 		goto out;
405 	err = 0;
406 	goto next_attr;
407 
408 end_enum:
409 
410 	if (!std5)
411 		goto out;
412 
413 	if (!is_match && name) {
414 		err = -ENOENT;
415 		goto out;
416 	}
417 
418 	if (std5->fa & FILE_ATTRIBUTE_READONLY)
419 		mode &= ~0222;
420 
421 	if (!names) {
422 		err = -EINVAL;
423 		goto out;
424 	}
425 
426 	if (names != le16_to_cpu(rec->hard_links)) {
427 		/* Correct minor error on the fly. Do not mark inode as dirty. */
428 		ntfs_inode_warn(inode, "Correct links count -> %u.", names);
429 		rec->hard_links = cpu_to_le16(names);
430 		ni->mi.dirty = true;
431 	}
432 
433 	set_nlink(inode, links);
434 
435 	if (S_ISDIR(mode)) {
436 		ni->std_fa |= FILE_ATTRIBUTE_DIRECTORY;
437 
438 		/*
439 		 * Dot and dot-dot should be included in count but was not
440 		 * included in enumeration.
441 		 * Usually a hard links to directories are disabled.
442 		 */
443 		inode->i_op = &ntfs_dir_inode_operations;
444 		inode->i_fop = unlikely(is_legacy_ntfs(sb)) ?
445 				       &ntfs_legacy_dir_operations :
446 				       &ntfs_dir_operations;
447 		ni->i_valid = 0;
448 	} else if (S_ISLNK(mode)) {
449 		ni->std_fa &= ~FILE_ATTRIBUTE_DIRECTORY;
450 		inode->i_op = &ntfs_link_inode_operations;
451 		inode->i_fop = NULL;
452 		inode_nohighmem(inode);
453 	} else if (S_ISREG(mode)) {
454 		ni->std_fa &= ~FILE_ATTRIBUTE_DIRECTORY;
455 		inode->i_op = &ntfs_file_inode_operations;
456 		inode->i_fop = unlikely(is_legacy_ntfs(sb)) ?
457 				       &ntfs_legacy_file_operations :
458 				       &ntfs_file_operations;
459 		inode->i_mapping->a_ops = is_compressed(ni) ? &ntfs_aops_cmpr :
460 							      &ntfs_aops;
461 		if (ino != MFT_REC_MFT)
462 			init_rwsem(&ni->file.run_lock);
463 	} else if (S_ISCHR(mode) || S_ISBLK(mode) || S_ISFIFO(mode) ||
464 		   S_ISSOCK(mode)) {
465 		inode->i_op = &ntfs_special_inode_operations;
466 		init_special_inode(inode, mode, inode->i_rdev);
467 	} else if (fname && fname->home.low == cpu_to_le32(MFT_REC_EXTEND) &&
468 		   fname->home.seq == cpu_to_le16(MFT_REC_EXTEND)) {
469 		/* Records in $Extend are not a files or general directories. */
470 		inode->i_op = &ntfs_file_inode_operations;
471 	} else {
472 		err = -EINVAL;
473 		goto out;
474 	}
475 
476 	if ((sbi->options->sys_immutable &&
477 	     (std5->fa & FILE_ATTRIBUTE_SYSTEM)) &&
478 	    !S_ISFIFO(mode) && !S_ISSOCK(mode) && !S_ISLNK(mode)) {
479 		inode->i_flags |= S_IMMUTABLE;
480 	} else {
481 		inode->i_flags &= ~S_IMMUTABLE;
482 	}
483 
484 	inode->i_mode = mode;
485 	if (!(ni->ni_flags & NI_FLAG_EA)) {
486 		/* If no xattr then no security (stored in xattr). */
487 		inode->i_flags |= S_NOSEC;
488 	}
489 
490 	if (ino == MFT_REC_MFT && !sb->s_root)
491 		sbi->mft.ni = NULL;
492 
493 	unlock_new_inode(inode);
494 
495 	return inode;
496 
497 out:
498 	if (ino == MFT_REC_MFT && !sb->s_root)
499 		sbi->mft.ni = NULL;
500 
501 	iget_failed(inode);
502 	return ERR_PTR(err);
503 }
504 
505 /*
506  * ntfs_test_inode
507  *
508  * Return: 1 if match.
509  */
510 static int ntfs_test_inode(struct inode *inode, void *data)
511 {
512 	struct MFT_REF *ref = data;
513 
514 	return ino_get(ref) == inode->i_ino;
515 }
516 
517 static int ntfs_set_inode(struct inode *inode, void *data)
518 {
519 	const struct MFT_REF *ref = data;
520 
521 	inode->i_ino = ino_get(ref);
522 	return 0;
523 }
524 
525 struct inode *ntfs_iget5(struct super_block *sb, const struct MFT_REF *ref,
526 			 const struct cpu_str *name)
527 {
528 	struct inode *inode;
529 
530 	inode = iget5_locked(sb, ino_get(ref), ntfs_test_inode, ntfs_set_inode,
531 			     (void *)ref);
532 	if (unlikely(!inode))
533 		return ERR_PTR(-ENOMEM);
534 
535 	/* If this is a freshly allocated inode, need to read it now. */
536 	if (inode->i_state & I_NEW)
537 		inode = ntfs_read_mft(inode, name, ref);
538 	else if (ref->seq != ntfs_i(inode)->mi.mrec->seq) {
539 		/* Inode overlaps? */
540 		_ntfs_bad_inode(inode);
541 	}
542 
543 	if (IS_ERR(inode) && name)
544 		ntfs_set_state(sb->s_fs_info, NTFS_DIRTY_ERROR);
545 
546 	return inode;
547 }
548 
549 enum get_block_ctx {
550 	GET_BLOCK_GENERAL = 0,
551 	GET_BLOCK_WRITE_BEGIN = 1,
552 	GET_BLOCK_DIRECT_IO_R = 2,
553 	GET_BLOCK_DIRECT_IO_W = 3,
554 	GET_BLOCK_BMAP = 4,
555 };
556 
557 static noinline int ntfs_get_block_vbo(struct inode *inode, u64 vbo,
558 				       struct buffer_head *bh, int create,
559 				       enum get_block_ctx ctx)
560 {
561 	struct super_block *sb = inode->i_sb;
562 	struct ntfs_sb_info *sbi = sb->s_fs_info;
563 	struct ntfs_inode *ni = ntfs_i(inode);
564 	struct folio *folio = bh->b_folio;
565 	u8 cluster_bits = sbi->cluster_bits;
566 	u32 block_size = sb->s_blocksize;
567 	u64 bytes, lbo, valid;
568 	u32 off;
569 	int err;
570 	CLST vcn, lcn, len;
571 	bool new;
572 
573 	/* Clear previous state. */
574 	clear_buffer_new(bh);
575 	clear_buffer_uptodate(bh);
576 
577 	if (is_resident(ni)) {
578 		bh->b_blocknr = RESIDENT_LCN;
579 		bh->b_size = block_size;
580 		if (!folio) {
581 			/* direct io (read) or bmap call */
582 			err = 0;
583 		} else {
584 			ni_lock(ni);
585 			err = attr_data_read_resident(ni, folio);
586 			ni_unlock(ni);
587 
588 			if (!err)
589 				set_buffer_uptodate(bh);
590 		}
591 		return err;
592 	}
593 
594 	vcn = vbo >> cluster_bits;
595 	off = vbo & sbi->cluster_mask;
596 	new = false;
597 
598 	err = attr_data_get_block(ni, vcn, 1, &lcn, &len, create ? &new : NULL,
599 				  create && sbi->cluster_size > PAGE_SIZE);
600 	if (err)
601 		goto out;
602 
603 	if (!len)
604 		return 0;
605 
606 	bytes = ((u64)len << cluster_bits) - off;
607 
608 	if (lcn == SPARSE_LCN) {
609 		if (!create) {
610 			if (bh->b_size > bytes)
611 				bh->b_size = bytes;
612 			return 0;
613 		}
614 		WARN_ON(1);
615 	}
616 
617 	if (new)
618 		set_buffer_new(bh);
619 
620 	lbo = ((u64)lcn << cluster_bits) + off;
621 
622 	set_buffer_mapped(bh);
623 	bh->b_bdev = sb->s_bdev;
624 	bh->b_blocknr = lbo >> sb->s_blocksize_bits;
625 
626 	valid = ni->i_valid;
627 
628 	if (ctx == GET_BLOCK_DIRECT_IO_W) {
629 		/* ntfs_direct_IO will update ni->i_valid. */
630 		if (vbo >= valid)
631 			set_buffer_new(bh);
632 	} else if (create) {
633 		/* Normal write. */
634 		if (bytes > bh->b_size)
635 			bytes = bh->b_size;
636 
637 		if (vbo >= valid)
638 			set_buffer_new(bh);
639 
640 		if (vbo + bytes > valid) {
641 			ni->i_valid = vbo + bytes;
642 			mark_inode_dirty(inode);
643 		}
644 	} else if (vbo >= valid) {
645 		/* Read out of valid data. */
646 		clear_buffer_mapped(bh);
647 	} else if (vbo + bytes <= valid) {
648 		/* Normal read. */
649 	} else if (vbo + block_size <= valid) {
650 		/* Normal short read. */
651 		bytes = block_size;
652 	} else {
653 		/*
654 		 * Read across valid size: vbo < valid && valid < vbo + block_size
655 		 */
656 		bytes = block_size;
657 
658 		if (folio) {
659 			u32 voff = valid - vbo;
660 
661 			bh->b_size = block_size;
662 			off = vbo & (PAGE_SIZE - 1);
663 			folio_set_bh(bh, folio, off);
664 
665 			if (bh_read(bh, 0) < 0) {
666 				err = -EIO;
667 				goto out;
668 			}
669 			folio_zero_segment(folio, off + voff, off + block_size);
670 		}
671 	}
672 
673 	if (bh->b_size > bytes)
674 		bh->b_size = bytes;
675 
676 #ifndef __LP64__
677 	if (ctx == GET_BLOCK_DIRECT_IO_W || ctx == GET_BLOCK_DIRECT_IO_R) {
678 		static_assert(sizeof(size_t) < sizeof(loff_t));
679 		if (bytes > 0x40000000u)
680 			bh->b_size = 0x40000000u;
681 	}
682 #endif
683 
684 	return 0;
685 
686 out:
687 	return err;
688 }
689 
690 int ntfs_get_block(struct inode *inode, sector_t vbn,
691 		   struct buffer_head *bh_result, int create)
692 {
693 	return ntfs_get_block_vbo(inode, (u64)vbn << inode->i_blkbits,
694 				  bh_result, create, GET_BLOCK_GENERAL);
695 }
696 
697 static int ntfs_get_block_bmap(struct inode *inode, sector_t vsn,
698 			       struct buffer_head *bh_result, int create)
699 {
700 	return ntfs_get_block_vbo(inode,
701 				  (u64)vsn << inode->i_sb->s_blocksize_bits,
702 				  bh_result, create, GET_BLOCK_BMAP);
703 }
704 
705 static sector_t ntfs_bmap(struct address_space *mapping, sector_t block)
706 {
707 	return generic_block_bmap(mapping, block, ntfs_get_block_bmap);
708 }
709 
710 static int ntfs_read_folio(struct file *file, struct folio *folio)
711 {
712 	int err;
713 	struct address_space *mapping = folio->mapping;
714 	struct inode *inode = mapping->host;
715 	struct ntfs_inode *ni = ntfs_i(inode);
716 
717 	if (is_resident(ni)) {
718 		ni_lock(ni);
719 		err = attr_data_read_resident(ni, folio);
720 		ni_unlock(ni);
721 		if (err != E_NTFS_NONRESIDENT) {
722 			folio_unlock(folio);
723 			return err;
724 		}
725 	}
726 
727 	if (is_compressed(ni)) {
728 		ni_lock(ni);
729 		err = ni_readpage_cmpr(ni, folio);
730 		ni_unlock(ni);
731 		return err;
732 	}
733 
734 	/* Normal + sparse files. */
735 	return mpage_read_folio(folio, ntfs_get_block);
736 }
737 
738 static void ntfs_readahead(struct readahead_control *rac)
739 {
740 	struct address_space *mapping = rac->mapping;
741 	struct inode *inode = mapping->host;
742 	struct ntfs_inode *ni = ntfs_i(inode);
743 	u64 valid;
744 	loff_t pos;
745 
746 	if (is_resident(ni)) {
747 		/* No readahead for resident. */
748 		return;
749 	}
750 
751 	if (is_compressed(ni)) {
752 		/* No readahead for compressed. */
753 		return;
754 	}
755 
756 	valid = ni->i_valid;
757 	pos = readahead_pos(rac);
758 
759 	if (valid < i_size_read(inode) && pos <= valid &&
760 	    valid < pos + readahead_length(rac)) {
761 		/* Range cross 'valid'. Read it page by page. */
762 		return;
763 	}
764 
765 	mpage_readahead(rac, ntfs_get_block);
766 }
767 
768 static int ntfs_get_block_direct_IO_R(struct inode *inode, sector_t iblock,
769 				      struct buffer_head *bh_result, int create)
770 {
771 	return ntfs_get_block_vbo(inode, (u64)iblock << inode->i_blkbits,
772 				  bh_result, create, GET_BLOCK_DIRECT_IO_R);
773 }
774 
775 static int ntfs_get_block_direct_IO_W(struct inode *inode, sector_t iblock,
776 				      struct buffer_head *bh_result, int create)
777 {
778 	return ntfs_get_block_vbo(inode, (u64)iblock << inode->i_blkbits,
779 				  bh_result, create, GET_BLOCK_DIRECT_IO_W);
780 }
781 
782 static ssize_t ntfs_direct_IO(struct kiocb *iocb, struct iov_iter *iter)
783 {
784 	struct file *file = iocb->ki_filp;
785 	struct address_space *mapping = file->f_mapping;
786 	struct inode *inode = mapping->host;
787 	struct ntfs_inode *ni = ntfs_i(inode);
788 	loff_t vbo = iocb->ki_pos;
789 	loff_t end;
790 	int wr = iov_iter_rw(iter) & WRITE;
791 	size_t iter_count = iov_iter_count(iter);
792 	loff_t valid;
793 	ssize_t ret;
794 
795 	if (is_resident(ni)) {
796 		/* Switch to buffered write. */
797 		ret = 0;
798 		goto out;
799 	}
800 
801 	ret = blockdev_direct_IO(iocb, inode, iter,
802 				 wr ? ntfs_get_block_direct_IO_W :
803 				      ntfs_get_block_direct_IO_R);
804 
805 	if (ret > 0)
806 		end = vbo + ret;
807 	else if (wr && ret == -EIOCBQUEUED)
808 		end = vbo + iter_count;
809 	else
810 		goto out;
811 
812 	valid = ni->i_valid;
813 	if (wr) {
814 		if (end > valid && !S_ISBLK(inode->i_mode)) {
815 			ni->i_valid = end;
816 			mark_inode_dirty(inode);
817 		}
818 	} else if (vbo < valid && valid < end) {
819 		/* Fix page. */
820 		iov_iter_revert(iter, end - valid);
821 		iov_iter_zero(end - valid, iter);
822 	}
823 
824 out:
825 	return ret;
826 }
827 
828 int ntfs_set_size(struct inode *inode, u64 new_size)
829 {
830 	struct super_block *sb = inode->i_sb;
831 	struct ntfs_sb_info *sbi = sb->s_fs_info;
832 	struct ntfs_inode *ni = ntfs_i(inode);
833 	int err;
834 
835 	/* Check for maximum file size. */
836 	if (is_sparsed(ni) || is_compressed(ni)) {
837 		if (new_size > sbi->maxbytes_sparse) {
838 			err = -EFBIG;
839 			goto out;
840 		}
841 	} else if (new_size > sbi->maxbytes) {
842 		err = -EFBIG;
843 		goto out;
844 	}
845 
846 	ni_lock(ni);
847 	down_write(&ni->file.run_lock);
848 
849 	err = attr_set_size(ni, ATTR_DATA, NULL, 0, &ni->file.run, new_size,
850 			    &ni->i_valid, true, NULL);
851 
852 	up_write(&ni->file.run_lock);
853 	ni_unlock(ni);
854 
855 	mark_inode_dirty(inode);
856 
857 out:
858 	return err;
859 }
860 
861 static int ntfs_resident_writepage(struct folio *folio,
862 				   struct writeback_control *wbc, void *data)
863 {
864 	struct address_space *mapping = data;
865 	struct inode *inode = mapping->host;
866 	struct ntfs_inode *ni = ntfs_i(inode);
867 	int ret;
868 
869 	if (unlikely(ntfs3_forced_shutdown(inode->i_sb)))
870 		return -EIO;
871 
872 	ni_lock(ni);
873 	ret = attr_data_write_resident(ni, folio);
874 	ni_unlock(ni);
875 
876 	if (ret != E_NTFS_NONRESIDENT)
877 		folio_unlock(folio);
878 	mapping_set_error(mapping, ret);
879 	return ret;
880 }
881 
882 static int ntfs_writepages(struct address_space *mapping,
883 			   struct writeback_control *wbc)
884 {
885 	struct inode *inode = mapping->host;
886 
887 	if (unlikely(ntfs3_forced_shutdown(inode->i_sb)))
888 		return -EIO;
889 
890 	if (is_resident(ntfs_i(inode)))
891 		return write_cache_pages(mapping, wbc, ntfs_resident_writepage,
892 					 mapping);
893 	return mpage_writepages(mapping, wbc, ntfs_get_block);
894 }
895 
896 static int ntfs_get_block_write_begin(struct inode *inode, sector_t vbn,
897 				      struct buffer_head *bh_result, int create)
898 {
899 	return ntfs_get_block_vbo(inode, (u64)vbn << inode->i_blkbits,
900 				  bh_result, create, GET_BLOCK_WRITE_BEGIN);
901 }
902 
903 int ntfs_write_begin(struct file *file, struct address_space *mapping,
904 		     loff_t pos, u32 len, struct page **pagep, void **fsdata)
905 {
906 	int err;
907 	struct inode *inode = mapping->host;
908 	struct ntfs_inode *ni = ntfs_i(inode);
909 
910 	if (unlikely(ntfs3_forced_shutdown(inode->i_sb)))
911 		return -EIO;
912 
913 	*pagep = NULL;
914 	if (is_resident(ni)) {
915 		struct folio *folio = __filemap_get_folio(
916 			mapping, pos >> PAGE_SHIFT, FGP_WRITEBEGIN,
917 			mapping_gfp_mask(mapping));
918 
919 		if (IS_ERR(folio)) {
920 			err = PTR_ERR(folio);
921 			goto out;
922 		}
923 
924 		ni_lock(ni);
925 		err = attr_data_read_resident(ni, folio);
926 		ni_unlock(ni);
927 
928 		if (!err) {
929 			*pagep = &folio->page;
930 			goto out;
931 		}
932 		folio_unlock(folio);
933 		folio_put(folio);
934 
935 		if (err != E_NTFS_NONRESIDENT)
936 			goto out;
937 	}
938 
939 	err = block_write_begin(mapping, pos, len, pagep,
940 				ntfs_get_block_write_begin);
941 
942 out:
943 	return err;
944 }
945 
946 /*
947  * ntfs_write_end - Address_space_operations::write_end.
948  */
949 int ntfs_write_end(struct file *file, struct address_space *mapping, loff_t pos,
950 		   u32 len, u32 copied, struct page *page, void *fsdata)
951 {
952 	struct folio *folio = page_folio(page);
953 	struct inode *inode = mapping->host;
954 	struct ntfs_inode *ni = ntfs_i(inode);
955 	u64 valid = ni->i_valid;
956 	bool dirty = false;
957 	int err;
958 
959 	if (is_resident(ni)) {
960 		ni_lock(ni);
961 		err = attr_data_write_resident(ni, folio);
962 		ni_unlock(ni);
963 		if (!err) {
964 			struct buffer_head *head = folio_buffers(folio);
965 			dirty = true;
966 			/* Clear any buffers in folio. */
967 			if (head) {
968 				struct buffer_head *bh = head;
969 
970 				do {
971 					clear_buffer_dirty(bh);
972 					clear_buffer_mapped(bh);
973 					set_buffer_uptodate(bh);
974 				} while (head != (bh = bh->b_this_page));
975 			}
976 			folio_mark_uptodate(folio);
977 			err = copied;
978 		}
979 		folio_unlock(folio);
980 		folio_put(folio);
981 	} else {
982 		err = generic_write_end(file, mapping, pos, len, copied, page,
983 					fsdata);
984 	}
985 
986 	if (err >= 0) {
987 		if (!(ni->std_fa & FILE_ATTRIBUTE_ARCHIVE)) {
988 			inode_set_mtime_to_ts(inode,
989 					      inode_set_ctime_current(inode));
990 			ni->std_fa |= FILE_ATTRIBUTE_ARCHIVE;
991 			dirty = true;
992 		}
993 
994 		if (valid != ni->i_valid) {
995 			/* ni->i_valid is changed in ntfs_get_block_vbo. */
996 			dirty = true;
997 		}
998 
999 		if (pos + err > inode->i_size) {
1000 			i_size_write(inode, pos + err);
1001 			dirty = true;
1002 		}
1003 
1004 		if (dirty)
1005 			mark_inode_dirty(inode);
1006 	}
1007 
1008 	return err;
1009 }
1010 
1011 int reset_log_file(struct inode *inode)
1012 {
1013 	int err;
1014 	loff_t pos = 0;
1015 	u32 log_size = inode->i_size;
1016 	struct address_space *mapping = inode->i_mapping;
1017 
1018 	for (;;) {
1019 		u32 len;
1020 		void *kaddr;
1021 		struct page *page;
1022 
1023 		len = pos + PAGE_SIZE > log_size ? (log_size - pos) : PAGE_SIZE;
1024 
1025 		err = block_write_begin(mapping, pos, len, &page,
1026 					ntfs_get_block_write_begin);
1027 		if (err)
1028 			goto out;
1029 
1030 		kaddr = kmap_atomic(page);
1031 		memset(kaddr, -1, len);
1032 		kunmap_atomic(kaddr);
1033 		flush_dcache_page(page);
1034 
1035 		err = block_write_end(NULL, mapping, pos, len, len, page, NULL);
1036 		if (err < 0)
1037 			goto out;
1038 		pos += len;
1039 
1040 		if (pos >= log_size)
1041 			break;
1042 		balance_dirty_pages_ratelimited(mapping);
1043 	}
1044 out:
1045 	mark_inode_dirty_sync(inode);
1046 
1047 	return err;
1048 }
1049 
1050 int ntfs3_write_inode(struct inode *inode, struct writeback_control *wbc)
1051 {
1052 	return _ni_write_inode(inode, wbc->sync_mode == WB_SYNC_ALL);
1053 }
1054 
1055 int ntfs_sync_inode(struct inode *inode)
1056 {
1057 	return _ni_write_inode(inode, 1);
1058 }
1059 
1060 /*
1061  * writeback_inode - Helper function for ntfs_flush_inodes().
1062  *
1063  * This writes both the inode and the file data blocks, waiting
1064  * for in flight data blocks before the start of the call.  It
1065  * does not wait for any io started during the call.
1066  */
1067 static int writeback_inode(struct inode *inode)
1068 {
1069 	int ret = sync_inode_metadata(inode, 0);
1070 
1071 	if (!ret)
1072 		ret = filemap_fdatawrite(inode->i_mapping);
1073 	return ret;
1074 }
1075 
1076 /*
1077  * ntfs_flush_inodes
1078  *
1079  * Write data and metadata corresponding to i1 and i2.  The io is
1080  * started but we do not wait for any of it to finish.
1081  *
1082  * filemap_flush() is used for the block device, so if there is a dirty
1083  * page for a block already in flight, we will not wait and start the
1084  * io over again.
1085  */
1086 int ntfs_flush_inodes(struct super_block *sb, struct inode *i1,
1087 		      struct inode *i2)
1088 {
1089 	int ret = 0;
1090 
1091 	if (i1)
1092 		ret = writeback_inode(i1);
1093 	if (!ret && i2)
1094 		ret = writeback_inode(i2);
1095 	if (!ret)
1096 		ret = filemap_flush(sb->s_bdev_file->f_mapping);
1097 	return ret;
1098 }
1099 
1100 /*
1101  * Helper function to read file.
1102  */
1103 int inode_read_data(struct inode *inode, void *data, size_t bytes)
1104 {
1105 	pgoff_t idx;
1106 	struct address_space *mapping = inode->i_mapping;
1107 
1108 	for (idx = 0; bytes; idx++) {
1109 		size_t op = bytes > PAGE_SIZE ? PAGE_SIZE : bytes;
1110 		struct page *page = read_mapping_page(mapping, idx, NULL);
1111 		void *kaddr;
1112 
1113 		if (IS_ERR(page))
1114 			return PTR_ERR(page);
1115 
1116 		kaddr = kmap_atomic(page);
1117 		memcpy(data, kaddr, op);
1118 		kunmap_atomic(kaddr);
1119 
1120 		put_page(page);
1121 
1122 		bytes -= op;
1123 		data = Add2Ptr(data, PAGE_SIZE);
1124 	}
1125 	return 0;
1126 }
1127 
1128 /*
1129  * ntfs_reparse_bytes
1130  *
1131  * Number of bytes for REPARSE_DATA_BUFFER(IO_REPARSE_TAG_SYMLINK)
1132  * for unicode string of @uni_len length.
1133  */
1134 static inline u32 ntfs_reparse_bytes(u32 uni_len)
1135 {
1136 	/* Header + unicode string + decorated unicode string. */
1137 	return sizeof(short) * (2 * uni_len + 4) +
1138 	       offsetof(struct REPARSE_DATA_BUFFER,
1139 			SymbolicLinkReparseBuffer.PathBuffer);
1140 }
1141 
1142 static struct REPARSE_DATA_BUFFER *
1143 ntfs_create_reparse_buffer(struct ntfs_sb_info *sbi, const char *symname,
1144 			   u32 size, u16 *nsize)
1145 {
1146 	int i, err;
1147 	struct REPARSE_DATA_BUFFER *rp;
1148 	__le16 *rp_name;
1149 	typeof(rp->SymbolicLinkReparseBuffer) *rs;
1150 
1151 	rp = kzalloc(ntfs_reparse_bytes(2 * size + 2), GFP_NOFS);
1152 	if (!rp)
1153 		return ERR_PTR(-ENOMEM);
1154 
1155 	rs = &rp->SymbolicLinkReparseBuffer;
1156 	rp_name = rs->PathBuffer;
1157 
1158 	/* Convert link name to UTF-16. */
1159 	err = ntfs_nls_to_utf16(sbi, symname, size,
1160 				(struct cpu_str *)(rp_name - 1), 2 * size,
1161 				UTF16_LITTLE_ENDIAN);
1162 	if (err < 0)
1163 		goto out;
1164 
1165 	/* err = the length of unicode name of symlink. */
1166 	*nsize = ntfs_reparse_bytes(err);
1167 
1168 	if (*nsize > sbi->reparse.max_size) {
1169 		err = -EFBIG;
1170 		goto out;
1171 	}
1172 
1173 	/* Translate Linux '/' into Windows '\'. */
1174 	for (i = 0; i < err; i++) {
1175 		if (rp_name[i] == cpu_to_le16('/'))
1176 			rp_name[i] = cpu_to_le16('\\');
1177 	}
1178 
1179 	rp->ReparseTag = IO_REPARSE_TAG_SYMLINK;
1180 	rp->ReparseDataLength =
1181 		cpu_to_le16(*nsize - offsetof(struct REPARSE_DATA_BUFFER,
1182 					      SymbolicLinkReparseBuffer));
1183 
1184 	/* PrintName + SubstituteName. */
1185 	rs->SubstituteNameOffset = cpu_to_le16(sizeof(short) * err);
1186 	rs->SubstituteNameLength = cpu_to_le16(sizeof(short) * err + 8);
1187 	rs->PrintNameLength = rs->SubstituteNameOffset;
1188 
1189 	/*
1190 	 * TODO: Use relative path if possible to allow Windows to
1191 	 * parse this path.
1192 	 * 0-absolute path 1- relative path (SYMLINK_FLAG_RELATIVE).
1193 	 */
1194 	rs->Flags = 0;
1195 
1196 	memmove(rp_name + err + 4, rp_name, sizeof(short) * err);
1197 
1198 	/* Decorate SubstituteName. */
1199 	rp_name += err;
1200 	rp_name[0] = cpu_to_le16('\\');
1201 	rp_name[1] = cpu_to_le16('?');
1202 	rp_name[2] = cpu_to_le16('?');
1203 	rp_name[3] = cpu_to_le16('\\');
1204 
1205 	return rp;
1206 out:
1207 	kfree(rp);
1208 	return ERR_PTR(err);
1209 }
1210 
1211 /*
1212  * ntfs_create_inode
1213  *
1214  * Helper function for:
1215  * - ntfs_create
1216  * - ntfs_mknod
1217  * - ntfs_symlink
1218  * - ntfs_mkdir
1219  * - ntfs_atomic_open
1220  *
1221  * NOTE: if fnd != NULL (ntfs_atomic_open) then @dir is locked
1222  */
1223 int ntfs_create_inode(struct mnt_idmap *idmap, struct inode *dir,
1224 		      struct dentry *dentry, const struct cpu_str *uni,
1225 		      umode_t mode, dev_t dev, const char *symname, u32 size,
1226 		      struct ntfs_fnd *fnd)
1227 {
1228 	int err;
1229 	struct super_block *sb = dir->i_sb;
1230 	struct ntfs_sb_info *sbi = sb->s_fs_info;
1231 	const struct qstr *name = &dentry->d_name;
1232 	CLST ino = 0;
1233 	struct ntfs_inode *dir_ni = ntfs_i(dir);
1234 	struct ntfs_inode *ni = NULL;
1235 	struct inode *inode = NULL;
1236 	struct ATTRIB *attr;
1237 	struct ATTR_STD_INFO5 *std5;
1238 	struct ATTR_FILE_NAME *fname;
1239 	struct MFT_REC *rec;
1240 	u32 asize, dsize, sd_size;
1241 	enum FILE_ATTRIBUTE fa;
1242 	__le32 security_id = SECURITY_ID_INVALID;
1243 	CLST vcn;
1244 	const void *sd;
1245 	u16 t16, nsize = 0, aid = 0;
1246 	struct INDEX_ROOT *root, *dir_root;
1247 	struct NTFS_DE *e, *new_de = NULL;
1248 	struct REPARSE_DATA_BUFFER *rp = NULL;
1249 	bool rp_inserted = false;
1250 
1251 	/* New file will be resident or non resident. */
1252 	const bool new_file_resident = 1;
1253 
1254 	if (!fnd)
1255 		ni_lock_dir(dir_ni);
1256 
1257 	dir_root = indx_get_root(&dir_ni->dir, dir_ni, NULL, NULL);
1258 	if (!dir_root) {
1259 		err = -EINVAL;
1260 		goto out1;
1261 	}
1262 
1263 	if (S_ISDIR(mode)) {
1264 		/* Use parent's directory attributes. */
1265 		fa = dir_ni->std_fa | FILE_ATTRIBUTE_DIRECTORY |
1266 		     FILE_ATTRIBUTE_ARCHIVE;
1267 		/*
1268 		 * By default child directory inherits parent attributes.
1269 		 * Root directory is hidden + system.
1270 		 * Make an exception for children in root.
1271 		 */
1272 		if (dir->i_ino == MFT_REC_ROOT)
1273 			fa &= ~(FILE_ATTRIBUTE_HIDDEN | FILE_ATTRIBUTE_SYSTEM);
1274 	} else if (S_ISLNK(mode)) {
1275 		/* It is good idea that link should be the same type (file/dir) as target */
1276 		fa = FILE_ATTRIBUTE_REPARSE_POINT;
1277 
1278 		/*
1279 		 * Linux: there are dir/file/symlink and so on.
1280 		 * NTFS: symlinks are "dir + reparse" or "file + reparse"
1281 		 * It is good idea to create:
1282 		 * dir + reparse if 'symname' points to directory
1283 		 * or
1284 		 * file + reparse if 'symname' points to file
1285 		 * Unfortunately kern_path hangs if symname contains 'dir'.
1286 		 */
1287 
1288 		/*
1289 		 *	struct path path;
1290 		 *
1291 		 *	if (!kern_path(symname, LOOKUP_FOLLOW, &path)){
1292 		 *		struct inode *target = d_inode(path.dentry);
1293 		 *
1294 		 *		if (S_ISDIR(target->i_mode))
1295 		 *			fa |= FILE_ATTRIBUTE_DIRECTORY;
1296 		 *		// if ( target->i_sb == sb ){
1297 		 *		//	use relative path?
1298 		 *		// }
1299 		 *		path_put(&path);
1300 		 *	}
1301 		 */
1302 	} else if (S_ISREG(mode)) {
1303 		if (sbi->options->sparse) {
1304 			/* Sparsed regular file, cause option 'sparse'. */
1305 			fa = FILE_ATTRIBUTE_SPARSE_FILE |
1306 			     FILE_ATTRIBUTE_ARCHIVE;
1307 		} else if (dir_ni->std_fa & FILE_ATTRIBUTE_COMPRESSED) {
1308 			/* Compressed regular file, if parent is compressed. */
1309 			fa = FILE_ATTRIBUTE_COMPRESSED | FILE_ATTRIBUTE_ARCHIVE;
1310 		} else {
1311 			/* Regular file, default attributes. */
1312 			fa = FILE_ATTRIBUTE_ARCHIVE;
1313 		}
1314 	} else {
1315 		fa = FILE_ATTRIBUTE_ARCHIVE;
1316 	}
1317 
1318 	/* If option "hide_dot_files" then set hidden attribute for dot files. */
1319 	if (sbi->options->hide_dot_files && name->name[0] == '.')
1320 		fa |= FILE_ATTRIBUTE_HIDDEN;
1321 
1322 	if (!(mode & 0222))
1323 		fa |= FILE_ATTRIBUTE_READONLY;
1324 
1325 	/* Allocate PATH_MAX bytes. */
1326 	new_de = __getname();
1327 	if (!new_de) {
1328 		err = -ENOMEM;
1329 		goto out1;
1330 	}
1331 
1332 	if (unlikely(ntfs3_forced_shutdown(sb))) {
1333 		err = -EIO;
1334 		goto out2;
1335 	}
1336 
1337 	/* Mark rw ntfs as dirty. it will be cleared at umount. */
1338 	ntfs_set_state(sbi, NTFS_DIRTY_DIRTY);
1339 
1340 	/* Step 1: allocate and fill new mft record. */
1341 	err = ntfs_look_free_mft(sbi, &ino, false, NULL, NULL);
1342 	if (err)
1343 		goto out2;
1344 
1345 	ni = ntfs_new_inode(sbi, ino, S_ISDIR(mode) ? RECORD_FLAG_DIR : 0);
1346 	if (IS_ERR(ni)) {
1347 		err = PTR_ERR(ni);
1348 		ni = NULL;
1349 		goto out3;
1350 	}
1351 	inode = &ni->vfs_inode;
1352 	inode_init_owner(idmap, inode, dir, mode);
1353 	mode = inode->i_mode;
1354 
1355 	ni->i_crtime = current_time(inode);
1356 
1357 	rec = ni->mi.mrec;
1358 	rec->hard_links = cpu_to_le16(1);
1359 	attr = Add2Ptr(rec, le16_to_cpu(rec->attr_off));
1360 
1361 	/* Get default security id. */
1362 	sd = s_default_security;
1363 	sd_size = sizeof(s_default_security);
1364 
1365 	if (is_ntfs3(sbi)) {
1366 		security_id = dir_ni->std_security_id;
1367 		if (le32_to_cpu(security_id) < SECURITY_ID_FIRST) {
1368 			security_id = sbi->security.def_security_id;
1369 
1370 			if (security_id == SECURITY_ID_INVALID &&
1371 			    !ntfs_insert_security(sbi, sd, sd_size,
1372 						  &security_id, NULL))
1373 				sbi->security.def_security_id = security_id;
1374 		}
1375 	}
1376 
1377 	/* Insert standard info. */
1378 	std5 = Add2Ptr(attr, SIZEOF_RESIDENT);
1379 
1380 	if (security_id == SECURITY_ID_INVALID) {
1381 		dsize = sizeof(struct ATTR_STD_INFO);
1382 	} else {
1383 		dsize = sizeof(struct ATTR_STD_INFO5);
1384 		std5->security_id = security_id;
1385 		ni->std_security_id = security_id;
1386 	}
1387 	asize = SIZEOF_RESIDENT + dsize;
1388 
1389 	attr->type = ATTR_STD;
1390 	attr->size = cpu_to_le32(asize);
1391 	attr->id = cpu_to_le16(aid++);
1392 	attr->res.data_off = SIZEOF_RESIDENT_LE;
1393 	attr->res.data_size = cpu_to_le32(dsize);
1394 
1395 	std5->cr_time = std5->m_time = std5->c_time = std5->a_time =
1396 		kernel2nt(&ni->i_crtime);
1397 
1398 	std5->fa = ni->std_fa = fa;
1399 
1400 	attr = Add2Ptr(attr, asize);
1401 
1402 	/* Insert file name. */
1403 	err = fill_name_de(sbi, new_de, name, uni);
1404 	if (err)
1405 		goto out4;
1406 
1407 	mi_get_ref(&ni->mi, &new_de->ref);
1408 
1409 	fname = (struct ATTR_FILE_NAME *)(new_de + 1);
1410 
1411 	if (sbi->options->windows_names &&
1412 	    !valid_windows_name(sbi, (struct le_str *)&fname->name_len)) {
1413 		err = -EINVAL;
1414 		goto out4;
1415 	}
1416 
1417 	mi_get_ref(&dir_ni->mi, &fname->home);
1418 	fname->dup.cr_time = fname->dup.m_time = fname->dup.c_time =
1419 		fname->dup.a_time = std5->cr_time;
1420 	fname->dup.alloc_size = fname->dup.data_size = 0;
1421 	fname->dup.fa = std5->fa;
1422 	fname->dup.ea_size = fname->dup.reparse = 0;
1423 
1424 	dsize = le16_to_cpu(new_de->key_size);
1425 	asize = ALIGN(SIZEOF_RESIDENT + dsize, 8);
1426 
1427 	attr->type = ATTR_NAME;
1428 	attr->size = cpu_to_le32(asize);
1429 	attr->res.data_off = SIZEOF_RESIDENT_LE;
1430 	attr->res.flags = RESIDENT_FLAG_INDEXED;
1431 	attr->id = cpu_to_le16(aid++);
1432 	attr->res.data_size = cpu_to_le32(dsize);
1433 	memcpy(Add2Ptr(attr, SIZEOF_RESIDENT), fname, dsize);
1434 
1435 	attr = Add2Ptr(attr, asize);
1436 
1437 	if (security_id == SECURITY_ID_INVALID) {
1438 		/* Insert security attribute. */
1439 		asize = SIZEOF_RESIDENT + ALIGN(sd_size, 8);
1440 
1441 		attr->type = ATTR_SECURE;
1442 		attr->size = cpu_to_le32(asize);
1443 		attr->id = cpu_to_le16(aid++);
1444 		attr->res.data_off = SIZEOF_RESIDENT_LE;
1445 		attr->res.data_size = cpu_to_le32(sd_size);
1446 		memcpy(Add2Ptr(attr, SIZEOF_RESIDENT), sd, sd_size);
1447 
1448 		attr = Add2Ptr(attr, asize);
1449 	}
1450 
1451 	attr->id = cpu_to_le16(aid++);
1452 	if (fa & FILE_ATTRIBUTE_DIRECTORY) {
1453 		/*
1454 		 * Regular directory or symlink to directory.
1455 		 * Create root attribute.
1456 		 */
1457 		dsize = sizeof(struct INDEX_ROOT) + sizeof(struct NTFS_DE);
1458 		asize = sizeof(I30_NAME) + SIZEOF_RESIDENT + dsize;
1459 
1460 		attr->type = ATTR_ROOT;
1461 		attr->size = cpu_to_le32(asize);
1462 
1463 		attr->name_len = ARRAY_SIZE(I30_NAME);
1464 		attr->name_off = SIZEOF_RESIDENT_LE;
1465 		attr->res.data_off =
1466 			cpu_to_le16(sizeof(I30_NAME) + SIZEOF_RESIDENT);
1467 		attr->res.data_size = cpu_to_le32(dsize);
1468 		memcpy(Add2Ptr(attr, SIZEOF_RESIDENT), I30_NAME,
1469 		       sizeof(I30_NAME));
1470 
1471 		root = Add2Ptr(attr, sizeof(I30_NAME) + SIZEOF_RESIDENT);
1472 		memcpy(root, dir_root, offsetof(struct INDEX_ROOT, ihdr));
1473 		root->ihdr.de_off = cpu_to_le32(sizeof(struct INDEX_HDR));
1474 		root->ihdr.used = cpu_to_le32(sizeof(struct INDEX_HDR) +
1475 					      sizeof(struct NTFS_DE));
1476 		root->ihdr.total = root->ihdr.used;
1477 
1478 		e = Add2Ptr(root, sizeof(struct INDEX_ROOT));
1479 		e->size = cpu_to_le16(sizeof(struct NTFS_DE));
1480 		e->flags = NTFS_IE_LAST;
1481 	} else if (S_ISLNK(mode)) {
1482 		/*
1483 		 * Symlink to file.
1484 		 * Create empty resident data attribute.
1485 		 */
1486 		asize = SIZEOF_RESIDENT;
1487 
1488 		/* Insert empty ATTR_DATA */
1489 		attr->type = ATTR_DATA;
1490 		attr->size = cpu_to_le32(SIZEOF_RESIDENT);
1491 		attr->name_off = SIZEOF_RESIDENT_LE;
1492 		attr->res.data_off = SIZEOF_RESIDENT_LE;
1493 	} else if (!new_file_resident && S_ISREG(mode)) {
1494 		/*
1495 		 * Regular file. Create empty non resident data attribute.
1496 		 */
1497 		attr->type = ATTR_DATA;
1498 		attr->non_res = 1;
1499 		attr->nres.evcn = cpu_to_le64(-1ll);
1500 		if (fa & FILE_ATTRIBUTE_SPARSE_FILE) {
1501 			attr->size = cpu_to_le32(SIZEOF_NONRESIDENT_EX + 8);
1502 			attr->name_off = SIZEOF_NONRESIDENT_EX_LE;
1503 			attr->flags = ATTR_FLAG_SPARSED;
1504 			asize = SIZEOF_NONRESIDENT_EX + 8;
1505 		} else if (fa & FILE_ATTRIBUTE_COMPRESSED) {
1506 			attr->size = cpu_to_le32(SIZEOF_NONRESIDENT_EX + 8);
1507 			attr->name_off = SIZEOF_NONRESIDENT_EX_LE;
1508 			attr->flags = ATTR_FLAG_COMPRESSED;
1509 			attr->nres.c_unit = NTFS_LZNT_CUNIT;
1510 			asize = SIZEOF_NONRESIDENT_EX + 8;
1511 		} else {
1512 			attr->size = cpu_to_le32(SIZEOF_NONRESIDENT + 8);
1513 			attr->name_off = SIZEOF_NONRESIDENT_LE;
1514 			asize = SIZEOF_NONRESIDENT + 8;
1515 		}
1516 		attr->nres.run_off = attr->name_off;
1517 	} else {
1518 		/*
1519 		 * Node. Create empty resident data attribute.
1520 		 */
1521 		attr->type = ATTR_DATA;
1522 		attr->size = cpu_to_le32(SIZEOF_RESIDENT);
1523 		attr->name_off = SIZEOF_RESIDENT_LE;
1524 		if (fa & FILE_ATTRIBUTE_SPARSE_FILE)
1525 			attr->flags = ATTR_FLAG_SPARSED;
1526 		else if (fa & FILE_ATTRIBUTE_COMPRESSED)
1527 			attr->flags = ATTR_FLAG_COMPRESSED;
1528 		attr->res.data_off = SIZEOF_RESIDENT_LE;
1529 		asize = SIZEOF_RESIDENT;
1530 		ni->ni_flags |= NI_FLAG_RESIDENT;
1531 	}
1532 
1533 	if (S_ISDIR(mode)) {
1534 		ni->ni_flags |= NI_FLAG_DIR;
1535 		err = indx_init(&ni->dir, sbi, attr, INDEX_MUTEX_I30);
1536 		if (err)
1537 			goto out4;
1538 	} else if (S_ISLNK(mode)) {
1539 		rp = ntfs_create_reparse_buffer(sbi, symname, size, &nsize);
1540 
1541 		if (IS_ERR(rp)) {
1542 			err = PTR_ERR(rp);
1543 			rp = NULL;
1544 			goto out4;
1545 		}
1546 
1547 		/*
1548 		 * Insert ATTR_REPARSE.
1549 		 */
1550 		attr = Add2Ptr(attr, asize);
1551 		attr->type = ATTR_REPARSE;
1552 		attr->id = cpu_to_le16(aid++);
1553 
1554 		/* Resident or non resident? */
1555 		asize = ALIGN(SIZEOF_RESIDENT + nsize, 8);
1556 		t16 = PtrOffset(rec, attr);
1557 
1558 		/*
1559 		 * Below function 'ntfs_save_wsl_perm' requires 0x78 bytes.
1560 		 * It is good idea to keep extended attributes resident.
1561 		 */
1562 		if (asize + t16 + 0x78 + 8 > sbi->record_size) {
1563 			CLST alen;
1564 			CLST clst = bytes_to_cluster(sbi, nsize);
1565 
1566 			/* Bytes per runs. */
1567 			t16 = sbi->record_size - t16 - SIZEOF_NONRESIDENT;
1568 
1569 			attr->non_res = 1;
1570 			attr->nres.evcn = cpu_to_le64(clst - 1);
1571 			attr->name_off = SIZEOF_NONRESIDENT_LE;
1572 			attr->nres.run_off = attr->name_off;
1573 			attr->nres.data_size = cpu_to_le64(nsize);
1574 			attr->nres.valid_size = attr->nres.data_size;
1575 			attr->nres.alloc_size =
1576 				cpu_to_le64(ntfs_up_cluster(sbi, nsize));
1577 
1578 			err = attr_allocate_clusters(sbi, &ni->file.run, 0, 0,
1579 						     clst, NULL, ALLOCATE_DEF,
1580 						     &alen, 0, NULL, NULL);
1581 			if (err)
1582 				goto out5;
1583 
1584 			err = run_pack(&ni->file.run, 0, clst,
1585 				       Add2Ptr(attr, SIZEOF_NONRESIDENT), t16,
1586 				       &vcn);
1587 			if (err < 0)
1588 				goto out5;
1589 
1590 			if (vcn != clst) {
1591 				err = -EINVAL;
1592 				goto out5;
1593 			}
1594 
1595 			asize = SIZEOF_NONRESIDENT + ALIGN(err, 8);
1596 			/* Write non resident data. */
1597 			err = ntfs_sb_write_run(sbi, &ni->file.run, 0, rp,
1598 						nsize, 0);
1599 			if (err)
1600 				goto out5;
1601 		} else {
1602 			attr->res.data_off = SIZEOF_RESIDENT_LE;
1603 			attr->res.data_size = cpu_to_le32(nsize);
1604 			memcpy(Add2Ptr(attr, SIZEOF_RESIDENT), rp, nsize);
1605 		}
1606 		/* Size of symlink equals the length of input string. */
1607 		inode->i_size = size;
1608 
1609 		attr->size = cpu_to_le32(asize);
1610 
1611 		err = ntfs_insert_reparse(sbi, IO_REPARSE_TAG_SYMLINK,
1612 					  &new_de->ref);
1613 		if (err)
1614 			goto out5;
1615 
1616 		rp_inserted = true;
1617 	}
1618 
1619 	attr = Add2Ptr(attr, asize);
1620 	attr->type = ATTR_END;
1621 
1622 	rec->used = cpu_to_le32(PtrOffset(rec, attr) + 8);
1623 	rec->next_attr_id = cpu_to_le16(aid);
1624 
1625 	inode->i_generation = le16_to_cpu(rec->seq);
1626 
1627 	if (S_ISDIR(mode)) {
1628 		inode->i_op = &ntfs_dir_inode_operations;
1629 		inode->i_fop = unlikely(is_legacy_ntfs(sb)) ?
1630 				       &ntfs_legacy_dir_operations :
1631 				       &ntfs_dir_operations;
1632 	} else if (S_ISLNK(mode)) {
1633 		inode->i_op = &ntfs_link_inode_operations;
1634 		inode->i_fop = NULL;
1635 		inode->i_mapping->a_ops = &ntfs_aops;
1636 		inode->i_size = size;
1637 		inode_nohighmem(inode);
1638 	} else if (S_ISREG(mode)) {
1639 		inode->i_op = &ntfs_file_inode_operations;
1640 		inode->i_fop = unlikely(is_legacy_ntfs(sb)) ?
1641 				       &ntfs_legacy_file_operations :
1642 				       &ntfs_file_operations;
1643 		inode->i_mapping->a_ops = is_compressed(ni) ? &ntfs_aops_cmpr :
1644 							      &ntfs_aops;
1645 		init_rwsem(&ni->file.run_lock);
1646 	} else {
1647 		inode->i_op = &ntfs_special_inode_operations;
1648 		init_special_inode(inode, mode, dev);
1649 	}
1650 
1651 #ifdef CONFIG_NTFS3_FS_POSIX_ACL
1652 	if (!S_ISLNK(mode) && (sb->s_flags & SB_POSIXACL)) {
1653 		err = ntfs_init_acl(idmap, inode, dir);
1654 		if (err)
1655 			goto out5;
1656 	} else
1657 #endif
1658 	{
1659 		inode->i_flags |= S_NOSEC;
1660 	}
1661 
1662 	/*
1663 	 * ntfs_init_acl and ntfs_save_wsl_perm update extended attribute.
1664 	 * The packed size of extended attribute is stored in direntry too.
1665 	 * 'fname' here points to inside new_de.
1666 	 */
1667 	err = ntfs_save_wsl_perm(inode, &fname->dup.ea_size);
1668 	if (err)
1669 		goto out6;
1670 
1671 	/*
1672 	 * update ea_size in file_name attribute too.
1673 	 * Use ni_find_attr cause layout of MFT record may be changed
1674 	 * in ntfs_init_acl and ntfs_save_wsl_perm.
1675 	 */
1676 	attr = ni_find_attr(ni, NULL, NULL, ATTR_NAME, NULL, 0, NULL, NULL);
1677 	if (attr) {
1678 		struct ATTR_FILE_NAME *fn;
1679 
1680 		fn = resident_data_ex(attr, SIZEOF_ATTRIBUTE_FILENAME);
1681 		if (fn)
1682 			fn->dup.ea_size = fname->dup.ea_size;
1683 	}
1684 
1685 	/* We do not need to update parent directory later */
1686 	ni->ni_flags &= ~NI_FLAG_UPDATE_PARENT;
1687 
1688 	/* Step 2: Add new name in index. */
1689 	err = indx_insert_entry(&dir_ni->dir, dir_ni, new_de, sbi, fnd, 0);
1690 	if (err)
1691 		goto out6;
1692 
1693 	/*
1694 	 * Call 'd_instantiate' after inode->i_op is set
1695 	 * but before finish_open.
1696 	 */
1697 	d_instantiate(dentry, inode);
1698 
1699 	/* Set original time. inode times (i_ctime) may be changed in ntfs_init_acl. */
1700 	inode_set_atime_to_ts(inode, ni->i_crtime);
1701 	inode_set_ctime_to_ts(inode, ni->i_crtime);
1702 	inode_set_mtime_to_ts(inode, ni->i_crtime);
1703 	inode_set_mtime_to_ts(dir, ni->i_crtime);
1704 	inode_set_ctime_to_ts(dir, ni->i_crtime);
1705 
1706 	mark_inode_dirty(dir);
1707 	mark_inode_dirty(inode);
1708 
1709 	/* Normal exit. */
1710 	goto out2;
1711 
1712 out6:
1713 	attr = ni_find_attr(ni, NULL, NULL, ATTR_EA, NULL, 0, NULL, NULL);
1714 	if (attr && attr->non_res) {
1715 		/* Delete ATTR_EA, if non-resident. */
1716 		attr_set_size(ni, ATTR_EA, NULL, 0, NULL, 0, NULL, false, NULL);
1717 	}
1718 
1719 	if (rp_inserted)
1720 		ntfs_remove_reparse(sbi, IO_REPARSE_TAG_SYMLINK, &new_de->ref);
1721 
1722 out5:
1723 	if (!S_ISDIR(mode))
1724 		run_deallocate(sbi, &ni->file.run, false);
1725 
1726 out4:
1727 	clear_rec_inuse(rec);
1728 	clear_nlink(inode);
1729 	ni->mi.dirty = false;
1730 	discard_new_inode(inode);
1731 out3:
1732 	ntfs_mark_rec_free(sbi, ino, false);
1733 
1734 out2:
1735 	__putname(new_de);
1736 	kfree(rp);
1737 
1738 out1:
1739 	if (!fnd)
1740 		ni_unlock(dir_ni);
1741 
1742 	if (!err)
1743 		unlock_new_inode(inode);
1744 
1745 	return err;
1746 }
1747 
1748 int ntfs_link_inode(struct inode *inode, struct dentry *dentry)
1749 {
1750 	int err;
1751 	struct ntfs_inode *ni = ntfs_i(inode);
1752 	struct ntfs_sb_info *sbi = inode->i_sb->s_fs_info;
1753 	struct NTFS_DE *de;
1754 
1755 	/* Allocate PATH_MAX bytes. */
1756 	de = __getname();
1757 	if (!de)
1758 		return -ENOMEM;
1759 
1760 	/* Mark rw ntfs as dirty. It will be cleared at umount. */
1761 	ntfs_set_state(sbi, NTFS_DIRTY_DIRTY);
1762 
1763 	/* Construct 'de'. */
1764 	err = fill_name_de(sbi, de, &dentry->d_name, NULL);
1765 	if (err)
1766 		goto out;
1767 
1768 	err = ni_add_name(ntfs_i(d_inode(dentry->d_parent)), ni, de);
1769 out:
1770 	__putname(de);
1771 	return err;
1772 }
1773 
1774 /*
1775  * ntfs_unlink_inode
1776  *
1777  * inode_operations::unlink
1778  * inode_operations::rmdir
1779  */
1780 int ntfs_unlink_inode(struct inode *dir, const struct dentry *dentry)
1781 {
1782 	int err;
1783 	struct ntfs_sb_info *sbi = dir->i_sb->s_fs_info;
1784 	struct inode *inode = d_inode(dentry);
1785 	struct ntfs_inode *ni = ntfs_i(inode);
1786 	struct ntfs_inode *dir_ni = ntfs_i(dir);
1787 	struct NTFS_DE *de, *de2 = NULL;
1788 	int undo_remove;
1789 
1790 	if (ntfs_is_meta_file(sbi, ni->mi.rno))
1791 		return -EINVAL;
1792 
1793 	/* Allocate PATH_MAX bytes. */
1794 	de = __getname();
1795 	if (!de)
1796 		return -ENOMEM;
1797 
1798 	ni_lock(ni);
1799 
1800 	if (S_ISDIR(inode->i_mode) && !dir_is_empty(inode)) {
1801 		err = -ENOTEMPTY;
1802 		goto out;
1803 	}
1804 
1805 	err = fill_name_de(sbi, de, &dentry->d_name, NULL);
1806 	if (err < 0)
1807 		goto out;
1808 
1809 	undo_remove = 0;
1810 	err = ni_remove_name(dir_ni, ni, de, &de2, &undo_remove);
1811 
1812 	if (!err) {
1813 		drop_nlink(inode);
1814 		inode_set_mtime_to_ts(dir, inode_set_ctime_current(dir));
1815 		mark_inode_dirty(dir);
1816 		inode_set_ctime_to_ts(inode, inode_get_ctime(dir));
1817 		if (inode->i_nlink)
1818 			mark_inode_dirty(inode);
1819 	} else if (!ni_remove_name_undo(dir_ni, ni, de, de2, undo_remove)) {
1820 		_ntfs_bad_inode(inode);
1821 	} else {
1822 		if (ni_is_dirty(dir))
1823 			mark_inode_dirty(dir);
1824 		if (ni_is_dirty(inode))
1825 			mark_inode_dirty(inode);
1826 	}
1827 
1828 out:
1829 	ni_unlock(ni);
1830 	__putname(de);
1831 	return err;
1832 }
1833 
1834 void ntfs_evict_inode(struct inode *inode)
1835 {
1836 	truncate_inode_pages_final(&inode->i_data);
1837 
1838 	invalidate_inode_buffers(inode);
1839 	clear_inode(inode);
1840 
1841 	ni_clear(ntfs_i(inode));
1842 }
1843 
1844 /*
1845  * ntfs_translate_junction
1846  *
1847  * Translate a Windows junction target to the Linux equivalent.
1848  * On junctions, targets are always absolute (they include the drive
1849  * letter). We have no way of knowing if the target is for the current
1850  * mounted device or not so we just assume it is.
1851  */
1852 static int ntfs_translate_junction(const struct super_block *sb,
1853 				   const struct dentry *link_de, char *target,
1854 				   int target_len, int target_max)
1855 {
1856 	int tl_len, err = target_len;
1857 	char *link_path_buffer = NULL, *link_path;
1858 	char *translated = NULL;
1859 	char *target_start;
1860 	int copy_len;
1861 
1862 	link_path_buffer = kmalloc(PATH_MAX, GFP_NOFS);
1863 	if (!link_path_buffer) {
1864 		err = -ENOMEM;
1865 		goto out;
1866 	}
1867 	/* Get link path, relative to mount point */
1868 	link_path = dentry_path_raw(link_de, link_path_buffer, PATH_MAX);
1869 	if (IS_ERR(link_path)) {
1870 		ntfs_err(sb, "Error getting link path");
1871 		err = -EINVAL;
1872 		goto out;
1873 	}
1874 
1875 	translated = kmalloc(PATH_MAX, GFP_NOFS);
1876 	if (!translated) {
1877 		err = -ENOMEM;
1878 		goto out;
1879 	}
1880 
1881 	/* Make translated path a relative path to mount point */
1882 	strcpy(translated, "./");
1883 	++link_path; /* Skip leading / */
1884 	for (tl_len = sizeof("./") - 1; *link_path; ++link_path) {
1885 		if (*link_path == '/') {
1886 			if (PATH_MAX - tl_len < sizeof("../")) {
1887 				ntfs_err(sb,
1888 					 "Link path %s has too many components",
1889 					 link_path);
1890 				err = -EINVAL;
1891 				goto out;
1892 			}
1893 			strcpy(translated + tl_len, "../");
1894 			tl_len += sizeof("../") - 1;
1895 		}
1896 	}
1897 
1898 	/* Skip drive letter */
1899 	target_start = target;
1900 	while (*target_start && *target_start != ':')
1901 		++target_start;
1902 
1903 	if (!*target_start) {
1904 		ntfs_err(sb, "Link target (%s) missing drive separator",
1905 			 target);
1906 		err = -EINVAL;
1907 		goto out;
1908 	}
1909 
1910 	/* Skip drive separator and leading /, if exists */
1911 	target_start += 1 + (target_start[1] == '/');
1912 	copy_len = target_len - (target_start - target);
1913 
1914 	if (PATH_MAX - tl_len <= copy_len) {
1915 		ntfs_err(sb, "Link target %s too large for buffer (%d <= %d)",
1916 			 target_start, PATH_MAX - tl_len, copy_len);
1917 		err = -EINVAL;
1918 		goto out;
1919 	}
1920 
1921 	/* translated path has a trailing / and target_start does not */
1922 	strcpy(translated + tl_len, target_start);
1923 	tl_len += copy_len;
1924 	if (target_max <= tl_len) {
1925 		ntfs_err(sb, "Target path %s too large for buffer (%d <= %d)",
1926 			 translated, target_max, tl_len);
1927 		err = -EINVAL;
1928 		goto out;
1929 	}
1930 	strcpy(target, translated);
1931 	err = tl_len;
1932 
1933 out:
1934 	kfree(link_path_buffer);
1935 	kfree(translated);
1936 	return err;
1937 }
1938 
1939 static noinline int ntfs_readlink_hlp(const struct dentry *link_de,
1940 				      struct inode *inode, char *buffer,
1941 				      int buflen)
1942 {
1943 	int i, err = -EINVAL;
1944 	struct ntfs_inode *ni = ntfs_i(inode);
1945 	struct super_block *sb = inode->i_sb;
1946 	struct ntfs_sb_info *sbi = sb->s_fs_info;
1947 	u64 size;
1948 	u16 ulen = 0;
1949 	void *to_free = NULL;
1950 	struct REPARSE_DATA_BUFFER *rp;
1951 	const __le16 *uname;
1952 	struct ATTRIB *attr;
1953 
1954 	/* Reparse data present. Try to parse it. */
1955 	static_assert(!offsetof(struct REPARSE_DATA_BUFFER, ReparseTag));
1956 	static_assert(sizeof(u32) == sizeof(rp->ReparseTag));
1957 
1958 	*buffer = 0;
1959 
1960 	attr = ni_find_attr(ni, NULL, NULL, ATTR_REPARSE, NULL, 0, NULL, NULL);
1961 	if (!attr)
1962 		goto out;
1963 
1964 	if (!attr->non_res) {
1965 		rp = resident_data_ex(attr, sizeof(struct REPARSE_DATA_BUFFER));
1966 		if (!rp)
1967 			goto out;
1968 		size = le32_to_cpu(attr->res.data_size);
1969 	} else {
1970 		size = le64_to_cpu(attr->nres.data_size);
1971 		rp = NULL;
1972 	}
1973 
1974 	if (size > sbi->reparse.max_size || size <= sizeof(u32))
1975 		goto out;
1976 
1977 	if (!rp) {
1978 		rp = kmalloc(size, GFP_NOFS);
1979 		if (!rp) {
1980 			err = -ENOMEM;
1981 			goto out;
1982 		}
1983 		to_free = rp;
1984 		/* Read into temporal buffer. */
1985 		err = ntfs_read_run_nb(sbi, &ni->file.run, 0, rp, size, NULL);
1986 		if (err)
1987 			goto out;
1988 	}
1989 
1990 	/* Microsoft Tag. */
1991 	switch (rp->ReparseTag) {
1992 	case IO_REPARSE_TAG_MOUNT_POINT:
1993 		/* Mount points and junctions. */
1994 		/* Can we use 'Rp->MountPointReparseBuffer.PrintNameLength'? */
1995 		if (size <= offsetof(struct REPARSE_DATA_BUFFER,
1996 				     MountPointReparseBuffer.PathBuffer))
1997 			goto out;
1998 		uname = Add2Ptr(rp,
1999 				offsetof(struct REPARSE_DATA_BUFFER,
2000 					 MountPointReparseBuffer.PathBuffer) +
2001 					le16_to_cpu(rp->MountPointReparseBuffer
2002 							    .PrintNameOffset));
2003 		ulen = le16_to_cpu(rp->MountPointReparseBuffer.PrintNameLength);
2004 		break;
2005 
2006 	case IO_REPARSE_TAG_SYMLINK:
2007 		/* FolderSymbolicLink */
2008 		/* Can we use 'Rp->SymbolicLinkReparseBuffer.PrintNameLength'? */
2009 		if (size <= offsetof(struct REPARSE_DATA_BUFFER,
2010 				     SymbolicLinkReparseBuffer.PathBuffer))
2011 			goto out;
2012 		uname = Add2Ptr(
2013 			rp, offsetof(struct REPARSE_DATA_BUFFER,
2014 				     SymbolicLinkReparseBuffer.PathBuffer) +
2015 				    le16_to_cpu(rp->SymbolicLinkReparseBuffer
2016 							.PrintNameOffset));
2017 		ulen = le16_to_cpu(
2018 			rp->SymbolicLinkReparseBuffer.PrintNameLength);
2019 		break;
2020 
2021 	case IO_REPARSE_TAG_CLOUD:
2022 	case IO_REPARSE_TAG_CLOUD_1:
2023 	case IO_REPARSE_TAG_CLOUD_2:
2024 	case IO_REPARSE_TAG_CLOUD_3:
2025 	case IO_REPARSE_TAG_CLOUD_4:
2026 	case IO_REPARSE_TAG_CLOUD_5:
2027 	case IO_REPARSE_TAG_CLOUD_6:
2028 	case IO_REPARSE_TAG_CLOUD_7:
2029 	case IO_REPARSE_TAG_CLOUD_8:
2030 	case IO_REPARSE_TAG_CLOUD_9:
2031 	case IO_REPARSE_TAG_CLOUD_A:
2032 	case IO_REPARSE_TAG_CLOUD_B:
2033 	case IO_REPARSE_TAG_CLOUD_C:
2034 	case IO_REPARSE_TAG_CLOUD_D:
2035 	case IO_REPARSE_TAG_CLOUD_E:
2036 	case IO_REPARSE_TAG_CLOUD_F:
2037 		err = sizeof("OneDrive") - 1;
2038 		if (err > buflen)
2039 			err = buflen;
2040 		memcpy(buffer, "OneDrive", err);
2041 		goto out;
2042 
2043 	default:
2044 		if (IsReparseTagMicrosoft(rp->ReparseTag)) {
2045 			/* Unknown Microsoft Tag. */
2046 			goto out;
2047 		}
2048 		if (!IsReparseTagNameSurrogate(rp->ReparseTag) ||
2049 		    size <= sizeof(struct REPARSE_POINT)) {
2050 			goto out;
2051 		}
2052 
2053 		/* Users tag. */
2054 		uname = Add2Ptr(rp, sizeof(struct REPARSE_POINT));
2055 		ulen = le16_to_cpu(rp->ReparseDataLength) -
2056 		       sizeof(struct REPARSE_POINT);
2057 	}
2058 
2059 	/* Convert nlen from bytes to UNICODE chars. */
2060 	ulen >>= 1;
2061 
2062 	/* Check that name is available. */
2063 	if (!ulen || uname + ulen > (__le16 *)Add2Ptr(rp, size))
2064 		goto out;
2065 
2066 	/* If name is already zero terminated then truncate it now. */
2067 	if (!uname[ulen - 1])
2068 		ulen -= 1;
2069 
2070 	err = ntfs_utf16_to_nls(sbi, uname, ulen, buffer, buflen);
2071 
2072 	if (err < 0)
2073 		goto out;
2074 
2075 	/* Translate Windows '\' into Linux '/'. */
2076 	for (i = 0; i < err; i++) {
2077 		if (buffer[i] == '\\')
2078 			buffer[i] = '/';
2079 	}
2080 
2081 	/* Always set last zero. */
2082 	buffer[err] = 0;
2083 
2084 	/* If this is a junction, translate the link target. */
2085 	if (rp->ReparseTag == IO_REPARSE_TAG_MOUNT_POINT)
2086 		err = ntfs_translate_junction(sb, link_de, buffer, err, buflen);
2087 
2088 out:
2089 	kfree(to_free);
2090 	return err;
2091 }
2092 
2093 static const char *ntfs_get_link(struct dentry *de, struct inode *inode,
2094 				 struct delayed_call *done)
2095 {
2096 	int err;
2097 	char *ret;
2098 
2099 	if (!de)
2100 		return ERR_PTR(-ECHILD);
2101 
2102 	ret = kmalloc(PAGE_SIZE, GFP_NOFS);
2103 	if (!ret)
2104 		return ERR_PTR(-ENOMEM);
2105 
2106 	err = ntfs_readlink_hlp(de, inode, ret, PAGE_SIZE);
2107 	if (err < 0) {
2108 		kfree(ret);
2109 		return ERR_PTR(err);
2110 	}
2111 
2112 	set_delayed_call(done, kfree_link, ret);
2113 
2114 	return ret;
2115 }
2116 
2117 // clang-format off
2118 const struct inode_operations ntfs_link_inode_operations = {
2119 	.get_link	= ntfs_get_link,
2120 	.setattr	= ntfs3_setattr,
2121 	.listxattr	= ntfs_listxattr,
2122 };
2123 
2124 const struct address_space_operations ntfs_aops = {
2125 	.read_folio	= ntfs_read_folio,
2126 	.readahead	= ntfs_readahead,
2127 	.writepages	= ntfs_writepages,
2128 	.write_begin	= ntfs_write_begin,
2129 	.write_end	= ntfs_write_end,
2130 	.direct_IO	= ntfs_direct_IO,
2131 	.bmap		= ntfs_bmap,
2132 	.dirty_folio	= block_dirty_folio,
2133 	.migrate_folio	= buffer_migrate_folio,
2134 	.invalidate_folio = block_invalidate_folio,
2135 };
2136 
2137 const struct address_space_operations ntfs_aops_cmpr = {
2138 	.read_folio	= ntfs_read_folio,
2139 	.readahead	= ntfs_readahead,
2140 	.dirty_folio	= block_dirty_folio,
2141 };
2142 // clang-format on
2143