xref: /openbmc/linux/fs/ntfs3/super.c (revision 8bdc2a19)
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  *
4  * Copyright (C) 2019-2021 Paragon Software GmbH, All rights reserved.
5  *
6  *
7  *                 terminology
8  *
9  * cluster - allocation unit     - 512,1K,2K,4K,...,2M
10  * vcn - virtual cluster number  - Offset inside the file in clusters.
11  * vbo - virtual byte offset     - Offset inside the file in bytes.
12  * lcn - logical cluster number  - 0 based cluster in clusters heap.
13  * lbo - logical byte offset     - Absolute position inside volume.
14  * run - maps VCN to LCN         - Stored in attributes in packed form.
15  * attr - attribute segment      - std/name/data etc records inside MFT.
16  * mi  - MFT inode               - One MFT record(usually 1024 bytes or 4K), consists of attributes.
17  * ni  - NTFS inode              - Extends linux inode. consists of one or more mft inodes.
18  * index - unit inside directory - 2K, 4K, <=page size, does not depend on cluster size.
19  *
20  * WSL - Windows Subsystem for Linux
21  * https://docs.microsoft.com/en-us/windows/wsl/file-permissions
22  * It stores uid/gid/mode/dev in xattr
23  *
24  */
25 
26 #include <linux/blkdev.h>
27 #include <linux/buffer_head.h>
28 #include <linux/exportfs.h>
29 #include <linux/fs.h>
30 #include <linux/fs_context.h>
31 #include <linux/fs_parser.h>
32 #include <linux/log2.h>
33 #include <linux/module.h>
34 #include <linux/nls.h>
35 #include <linux/seq_file.h>
36 #include <linux/statfs.h>
37 
38 #include "debug.h"
39 #include "ntfs.h"
40 #include "ntfs_fs.h"
41 #ifdef CONFIG_NTFS3_LZX_XPRESS
42 #include "lib/lib.h"
43 #endif
44 
45 #ifdef CONFIG_PRINTK
46 /*
47  * ntfs_printk - Trace warnings/notices/errors.
48  *
49  * Thanks Joe Perches <joe@perches.com> for implementation
50  */
51 void ntfs_printk(const struct super_block *sb, const char *fmt, ...)
52 {
53 	struct va_format vaf;
54 	va_list args;
55 	int level;
56 	struct ntfs_sb_info *sbi = sb->s_fs_info;
57 
58 	/* Should we use different ratelimits for warnings/notices/errors? */
59 	if (!___ratelimit(&sbi->msg_ratelimit, "ntfs3"))
60 		return;
61 
62 	va_start(args, fmt);
63 
64 	level = printk_get_level(fmt);
65 	vaf.fmt = printk_skip_level(fmt);
66 	vaf.va = &args;
67 	printk("%c%cntfs3: %s: %pV\n", KERN_SOH_ASCII, level, sb->s_id, &vaf);
68 
69 	va_end(args);
70 }
71 
72 static char s_name_buf[512];
73 static atomic_t s_name_buf_cnt = ATOMIC_INIT(1); // 1 means 'free s_name_buf'.
74 
75 /*
76  * ntfs_inode_printk
77  *
78  * Print warnings/notices/errors about inode using name or inode number.
79  */
80 void ntfs_inode_printk(struct inode *inode, const char *fmt, ...)
81 {
82 	struct super_block *sb = inode->i_sb;
83 	struct ntfs_sb_info *sbi = sb->s_fs_info;
84 	char *name;
85 	va_list args;
86 	struct va_format vaf;
87 	int level;
88 
89 	if (!___ratelimit(&sbi->msg_ratelimit, "ntfs3"))
90 		return;
91 
92 	/* Use static allocated buffer, if possible. */
93 	name = atomic_dec_and_test(&s_name_buf_cnt)
94 		       ? s_name_buf
95 		       : kmalloc(sizeof(s_name_buf), GFP_NOFS);
96 
97 	if (name) {
98 		struct dentry *de = d_find_alias(inode);
99 		const u32 name_len = ARRAY_SIZE(s_name_buf) - 1;
100 
101 		if (de) {
102 			spin_lock(&de->d_lock);
103 			snprintf(name, name_len, " \"%s\"", de->d_name.name);
104 			spin_unlock(&de->d_lock);
105 			name[name_len] = 0; /* To be sure. */
106 		} else {
107 			name[0] = 0;
108 		}
109 		dput(de); /* Cocci warns if placed in branch "if (de)" */
110 	}
111 
112 	va_start(args, fmt);
113 
114 	level = printk_get_level(fmt);
115 	vaf.fmt = printk_skip_level(fmt);
116 	vaf.va = &args;
117 
118 	printk("%c%cntfs3: %s: ino=%lx,%s %pV\n", KERN_SOH_ASCII, level,
119 	       sb->s_id, inode->i_ino, name ? name : "", &vaf);
120 
121 	va_end(args);
122 
123 	atomic_inc(&s_name_buf_cnt);
124 	if (name != s_name_buf)
125 		kfree(name);
126 }
127 #endif
128 
129 /*
130  * Shared memory struct.
131  *
132  * On-disk ntfs's upcase table is created by ntfs formatter.
133  * 'upcase' table is 128K bytes of memory.
134  * We should read it into memory when mounting.
135  * Several ntfs volumes likely use the same 'upcase' table.
136  * It is good idea to share in-memory 'upcase' table between different volumes.
137  * Unfortunately winxp/vista/win7 use different upcase tables.
138  */
139 static DEFINE_SPINLOCK(s_shared_lock);
140 
141 static struct {
142 	void *ptr;
143 	u32 len;
144 	int cnt;
145 } s_shared[8];
146 
147 /*
148  * ntfs_set_shared
149  *
150  * Return:
151  * * @ptr - If pointer was saved in shared memory.
152  * * NULL - If pointer was not shared.
153  */
154 void *ntfs_set_shared(void *ptr, u32 bytes)
155 {
156 	void *ret = NULL;
157 	int i, j = -1;
158 
159 	spin_lock(&s_shared_lock);
160 	for (i = 0; i < ARRAY_SIZE(s_shared); i++) {
161 		if (!s_shared[i].cnt) {
162 			j = i;
163 		} else if (bytes == s_shared[i].len &&
164 			   !memcmp(s_shared[i].ptr, ptr, bytes)) {
165 			s_shared[i].cnt += 1;
166 			ret = s_shared[i].ptr;
167 			break;
168 		}
169 	}
170 
171 	if (!ret && j != -1) {
172 		s_shared[j].ptr = ptr;
173 		s_shared[j].len = bytes;
174 		s_shared[j].cnt = 1;
175 		ret = ptr;
176 	}
177 	spin_unlock(&s_shared_lock);
178 
179 	return ret;
180 }
181 
182 /*
183  * ntfs_put_shared
184  *
185  * Return:
186  * * @ptr - If pointer is not shared anymore.
187  * * NULL - If pointer is still shared.
188  */
189 void *ntfs_put_shared(void *ptr)
190 {
191 	void *ret = ptr;
192 	int i;
193 
194 	spin_lock(&s_shared_lock);
195 	for (i = 0; i < ARRAY_SIZE(s_shared); i++) {
196 		if (s_shared[i].cnt && s_shared[i].ptr == ptr) {
197 			if (--s_shared[i].cnt)
198 				ret = NULL;
199 			break;
200 		}
201 	}
202 	spin_unlock(&s_shared_lock);
203 
204 	return ret;
205 }
206 
207 static inline void put_mount_options(struct ntfs_mount_options *options)
208 {
209 	kfree(options->nls_name);
210 	unload_nls(options->nls);
211 	kfree(options);
212 }
213 
214 enum Opt {
215 	Opt_uid,
216 	Opt_gid,
217 	Opt_umask,
218 	Opt_dmask,
219 	Opt_fmask,
220 	Opt_immutable,
221 	Opt_discard,
222 	Opt_force,
223 	Opt_sparse,
224 	Opt_nohidden,
225 	Opt_showmeta,
226 	Opt_acl,
227 	Opt_iocharset,
228 	Opt_prealloc,
229 	Opt_noacsrules,
230 	Opt_err,
231 };
232 
233 static const struct fs_parameter_spec ntfs_fs_parameters[] = {
234 	fsparam_u32("uid",			Opt_uid),
235 	fsparam_u32("gid",			Opt_gid),
236 	fsparam_u32oct("umask",			Opt_umask),
237 	fsparam_u32oct("dmask",			Opt_dmask),
238 	fsparam_u32oct("fmask",			Opt_fmask),
239 	fsparam_flag_no("sys_immutable",	Opt_immutable),
240 	fsparam_flag_no("discard",		Opt_discard),
241 	fsparam_flag_no("force",		Opt_force),
242 	fsparam_flag_no("sparse",		Opt_sparse),
243 	fsparam_flag_no("hidden",		Opt_nohidden),
244 	fsparam_flag_no("acl",			Opt_acl),
245 	fsparam_flag_no("showmeta",		Opt_showmeta),
246 	fsparam_flag_no("prealloc",		Opt_prealloc),
247 	fsparam_flag_no("acsrules",		Opt_noacsrules),
248 	fsparam_string("iocharset",		Opt_iocharset),
249 	{}
250 };
251 
252 /*
253  * Load nls table or if @nls is utf8 then return NULL.
254  */
255 static struct nls_table *ntfs_load_nls(char *nls)
256 {
257 	struct nls_table *ret;
258 
259 	if (!nls)
260 		nls = CONFIG_NLS_DEFAULT;
261 
262 	if (strcmp(nls, "utf8") == 0)
263 		return NULL;
264 
265 	if (strcmp(nls, CONFIG_NLS_DEFAULT) == 0)
266 		return load_nls_default();
267 
268 	ret = load_nls(nls);
269 	if (ret)
270 		return ret;
271 
272 	return ERR_PTR(-EINVAL);
273 }
274 
275 static int ntfs_fs_parse_param(struct fs_context *fc,
276 			       struct fs_parameter *param)
277 {
278 	struct ntfs_mount_options *opts = fc->fs_private;
279 	struct fs_parse_result result;
280 	int opt;
281 
282 	opt = fs_parse(fc, ntfs_fs_parameters, param, &result);
283 	if (opt < 0)
284 		return opt;
285 
286 	switch (opt) {
287 	case Opt_uid:
288 		opts->fs_uid = make_kuid(current_user_ns(), result.uint_32);
289 		if (!uid_valid(opts->fs_uid))
290 			return invalf(fc, "ntfs3: Invalid value for uid.");
291 		break;
292 	case Opt_gid:
293 		opts->fs_gid = make_kgid(current_user_ns(), result.uint_32);
294 		if (!gid_valid(opts->fs_gid))
295 			return invalf(fc, "ntfs3: Invalid value for gid.");
296 		break;
297 	case Opt_umask:
298 		if (result.uint_32 & ~07777)
299 			return invalf(fc, "ntfs3: Invalid value for umask.");
300 		opts->fs_fmask_inv = ~result.uint_32;
301 		opts->fs_dmask_inv = ~result.uint_32;
302 		opts->fmask = 1;
303 		opts->dmask = 1;
304 		break;
305 	case Opt_dmask:
306 		if (result.uint_32 & ~07777)
307 			return invalf(fc, "ntfs3: Invalid value for dmask.");
308 		opts->fs_dmask_inv = ~result.uint_32;
309 		opts->dmask = 1;
310 		break;
311 	case Opt_fmask:
312 		if (result.uint_32 & ~07777)
313 			return invalf(fc, "ntfs3: Invalid value for fmask.");
314 		opts->fs_fmask_inv = ~result.uint_32;
315 		opts->fmask = 1;
316 		break;
317 	case Opt_immutable:
318 		opts->sys_immutable = result.negated ? 0 : 1;
319 		break;
320 	case Opt_discard:
321 		opts->discard = result.negated ? 0 : 1;
322 		break;
323 	case Opt_force:
324 		opts->force = result.negated ? 0 : 1;
325 		break;
326 	case Opt_sparse:
327 		opts->sparse = result.negated ? 0 : 1;
328 		break;
329 	case Opt_nohidden:
330 		opts->nohidden = result.negated ? 1 : 0;
331 		break;
332 	case Opt_acl:
333 		if (!result.negated)
334 #ifdef CONFIG_NTFS3_FS_POSIX_ACL
335 			fc->sb_flags |= SB_POSIXACL;
336 #else
337 			return invalf(fc, "ntfs3: Support for ACL not compiled in!");
338 #endif
339 		else
340 			fc->sb_flags &= ~SB_POSIXACL;
341 		break;
342 	case Opt_showmeta:
343 		opts->showmeta = result.negated ? 0 : 1;
344 		break;
345 	case Opt_iocharset:
346 		kfree(opts->nls_name);
347 		opts->nls_name = param->string;
348 		param->string = NULL;
349 		break;
350 	case Opt_prealloc:
351 		opts->prealloc = result.negated ? 0 : 1;
352 		break;
353 	case Opt_noacsrules:
354 		opts->noacsrules = result.negated ? 1 : 0;
355 		break;
356 	default:
357 		/* Should not be here unless we forget add case. */
358 		return -EINVAL;
359 	}
360 	return 0;
361 }
362 
363 static int ntfs_fs_reconfigure(struct fs_context *fc)
364 {
365 	struct super_block *sb = fc->root->d_sb;
366 	struct ntfs_sb_info *sbi = sb->s_fs_info;
367 	struct ntfs_mount_options *new_opts = fc->fs_private;
368 	int ro_rw;
369 
370 	ro_rw = sb_rdonly(sb) && !(fc->sb_flags & SB_RDONLY);
371 	if (ro_rw && (sbi->flags & NTFS_FLAGS_NEED_REPLAY)) {
372 		errorf(fc, "ntfs3: Couldn't remount rw because journal is not replayed. Please umount/remount instead\n");
373 		return -EINVAL;
374 	}
375 
376 	new_opts->nls = ntfs_load_nls(new_opts->nls_name);
377 	if (IS_ERR(new_opts->nls)) {
378 		new_opts->nls = NULL;
379 		errorf(fc, "ntfs3: Cannot load iocharset %s", new_opts->nls_name);
380 		return -EINVAL;
381 	}
382 	if (new_opts->nls != sbi->options->nls)
383 		return invalf(fc, "ntfs3: Cannot use different iocharset when remounting!");
384 
385 	sync_filesystem(sb);
386 
387 	if (ro_rw && (sbi->volume.flags & VOLUME_FLAG_DIRTY) &&
388 	    !new_opts->force) {
389 		errorf(fc, "ntfs3: Volume is dirty and \"force\" flag is not set!");
390 		return -EINVAL;
391 	}
392 
393 	memcpy(sbi->options, new_opts, sizeof(*new_opts));
394 
395 	return 0;
396 }
397 
398 static struct kmem_cache *ntfs_inode_cachep;
399 
400 static struct inode *ntfs_alloc_inode(struct super_block *sb)
401 {
402 	struct ntfs_inode *ni = alloc_inode_sb(sb, ntfs_inode_cachep, GFP_NOFS);
403 
404 	if (!ni)
405 		return NULL;
406 
407 	memset(ni, 0, offsetof(struct ntfs_inode, vfs_inode));
408 
409 	mutex_init(&ni->ni_lock);
410 
411 	return &ni->vfs_inode;
412 }
413 
414 static void ntfs_i_callback(struct rcu_head *head)
415 {
416 	struct inode *inode = container_of(head, struct inode, i_rcu);
417 	struct ntfs_inode *ni = ntfs_i(inode);
418 
419 	mutex_destroy(&ni->ni_lock);
420 
421 	kmem_cache_free(ntfs_inode_cachep, ni);
422 }
423 
424 static void ntfs_destroy_inode(struct inode *inode)
425 {
426 	call_rcu(&inode->i_rcu, ntfs_i_callback);
427 }
428 
429 static void init_once(void *foo)
430 {
431 	struct ntfs_inode *ni = foo;
432 
433 	inode_init_once(&ni->vfs_inode);
434 }
435 
436 /*
437  * put_ntfs - Noinline to reduce binary size.
438  */
439 static noinline void put_ntfs(struct ntfs_sb_info *sbi)
440 {
441 	kfree(sbi->new_rec);
442 	kvfree(ntfs_put_shared(sbi->upcase));
443 	kfree(sbi->def_table);
444 
445 	wnd_close(&sbi->mft.bitmap);
446 	wnd_close(&sbi->used.bitmap);
447 
448 	if (sbi->mft.ni)
449 		iput(&sbi->mft.ni->vfs_inode);
450 
451 	if (sbi->security.ni)
452 		iput(&sbi->security.ni->vfs_inode);
453 
454 	if (sbi->reparse.ni)
455 		iput(&sbi->reparse.ni->vfs_inode);
456 
457 	if (sbi->objid.ni)
458 		iput(&sbi->objid.ni->vfs_inode);
459 
460 	if (sbi->volume.ni)
461 		iput(&sbi->volume.ni->vfs_inode);
462 
463 	ntfs_update_mftmirr(sbi, 0);
464 
465 	indx_clear(&sbi->security.index_sii);
466 	indx_clear(&sbi->security.index_sdh);
467 	indx_clear(&sbi->reparse.index_r);
468 	indx_clear(&sbi->objid.index_o);
469 	kfree(sbi->compress.lznt);
470 #ifdef CONFIG_NTFS3_LZX_XPRESS
471 	xpress_free_decompressor(sbi->compress.xpress);
472 	lzx_free_decompressor(sbi->compress.lzx);
473 #endif
474 	kfree(sbi);
475 }
476 
477 static void ntfs_put_super(struct super_block *sb)
478 {
479 	struct ntfs_sb_info *sbi = sb->s_fs_info;
480 
481 	/* Mark rw ntfs as clear, if possible. */
482 	ntfs_set_state(sbi, NTFS_DIRTY_CLEAR);
483 
484 	put_mount_options(sbi->options);
485 	put_ntfs(sbi);
486 	sb->s_fs_info = NULL;
487 
488 	sync_blockdev(sb->s_bdev);
489 }
490 
491 static int ntfs_statfs(struct dentry *dentry, struct kstatfs *buf)
492 {
493 	struct super_block *sb = dentry->d_sb;
494 	struct ntfs_sb_info *sbi = sb->s_fs_info;
495 	struct wnd_bitmap *wnd = &sbi->used.bitmap;
496 
497 	buf->f_type = sb->s_magic;
498 	buf->f_bsize = sbi->cluster_size;
499 	buf->f_blocks = wnd->nbits;
500 
501 	buf->f_bfree = buf->f_bavail = wnd_zeroes(wnd);
502 	buf->f_fsid.val[0] = sbi->volume.ser_num;
503 	buf->f_fsid.val[1] = (sbi->volume.ser_num >> 32);
504 	buf->f_namelen = NTFS_NAME_LEN;
505 
506 	return 0;
507 }
508 
509 static int ntfs_show_options(struct seq_file *m, struct dentry *root)
510 {
511 	struct super_block *sb = root->d_sb;
512 	struct ntfs_sb_info *sbi = sb->s_fs_info;
513 	struct ntfs_mount_options *opts = sbi->options;
514 	struct user_namespace *user_ns = seq_user_ns(m);
515 
516 	seq_printf(m, ",uid=%u",
517 		  from_kuid_munged(user_ns, opts->fs_uid));
518 	seq_printf(m, ",gid=%u",
519 		  from_kgid_munged(user_ns, opts->fs_gid));
520 	if (opts->fmask)
521 		seq_printf(m, ",fmask=%04o", ~opts->fs_fmask_inv);
522 	if (opts->dmask)
523 		seq_printf(m, ",dmask=%04o", ~opts->fs_dmask_inv);
524 	if (opts->nls)
525 		seq_printf(m, ",iocharset=%s", opts->nls->charset);
526 	else
527 		seq_puts(m, ",iocharset=utf8");
528 	if (opts->sys_immutable)
529 		seq_puts(m, ",sys_immutable");
530 	if (opts->discard)
531 		seq_puts(m, ",discard");
532 	if (opts->sparse)
533 		seq_puts(m, ",sparse");
534 	if (opts->showmeta)
535 		seq_puts(m, ",showmeta");
536 	if (opts->nohidden)
537 		seq_puts(m, ",nohidden");
538 	if (opts->force)
539 		seq_puts(m, ",force");
540 	if (opts->noacsrules)
541 		seq_puts(m, ",noacsrules");
542 	if (opts->prealloc)
543 		seq_puts(m, ",prealloc");
544 	if (sb->s_flags & SB_POSIXACL)
545 		seq_puts(m, ",acl");
546 
547 	return 0;
548 }
549 
550 /*
551  * ntfs_sync_fs - super_operations::sync_fs
552  */
553 static int ntfs_sync_fs(struct super_block *sb, int wait)
554 {
555 	int err = 0, err2;
556 	struct ntfs_sb_info *sbi = sb->s_fs_info;
557 	struct ntfs_inode *ni;
558 	struct inode *inode;
559 
560 	ni = sbi->security.ni;
561 	if (ni) {
562 		inode = &ni->vfs_inode;
563 		err2 = _ni_write_inode(inode, wait);
564 		if (err2 && !err)
565 			err = err2;
566 	}
567 
568 	ni = sbi->objid.ni;
569 	if (ni) {
570 		inode = &ni->vfs_inode;
571 		err2 = _ni_write_inode(inode, wait);
572 		if (err2 && !err)
573 			err = err2;
574 	}
575 
576 	ni = sbi->reparse.ni;
577 	if (ni) {
578 		inode = &ni->vfs_inode;
579 		err2 = _ni_write_inode(inode, wait);
580 		if (err2 && !err)
581 			err = err2;
582 	}
583 
584 	if (!err)
585 		ntfs_set_state(sbi, NTFS_DIRTY_CLEAR);
586 
587 	ntfs_update_mftmirr(sbi, wait);
588 
589 	return err;
590 }
591 
592 static const struct super_operations ntfs_sops = {
593 	.alloc_inode = ntfs_alloc_inode,
594 	.destroy_inode = ntfs_destroy_inode,
595 	.evict_inode = ntfs_evict_inode,
596 	.put_super = ntfs_put_super,
597 	.statfs = ntfs_statfs,
598 	.show_options = ntfs_show_options,
599 	.sync_fs = ntfs_sync_fs,
600 	.write_inode = ntfs3_write_inode,
601 };
602 
603 static struct inode *ntfs_export_get_inode(struct super_block *sb, u64 ino,
604 					   u32 generation)
605 {
606 	struct MFT_REF ref;
607 	struct inode *inode;
608 
609 	ref.low = cpu_to_le32(ino);
610 #ifdef CONFIG_NTFS3_64BIT_CLUSTER
611 	ref.high = cpu_to_le16(ino >> 32);
612 #else
613 	ref.high = 0;
614 #endif
615 	ref.seq = cpu_to_le16(generation);
616 
617 	inode = ntfs_iget5(sb, &ref, NULL);
618 	if (!IS_ERR(inode) && is_bad_inode(inode)) {
619 		iput(inode);
620 		inode = ERR_PTR(-ESTALE);
621 	}
622 
623 	return inode;
624 }
625 
626 static struct dentry *ntfs_fh_to_dentry(struct super_block *sb, struct fid *fid,
627 					int fh_len, int fh_type)
628 {
629 	return generic_fh_to_dentry(sb, fid, fh_len, fh_type,
630 				    ntfs_export_get_inode);
631 }
632 
633 static struct dentry *ntfs_fh_to_parent(struct super_block *sb, struct fid *fid,
634 					int fh_len, int fh_type)
635 {
636 	return generic_fh_to_parent(sb, fid, fh_len, fh_type,
637 				    ntfs_export_get_inode);
638 }
639 
640 /* TODO: == ntfs_sync_inode */
641 static int ntfs_nfs_commit_metadata(struct inode *inode)
642 {
643 	return _ni_write_inode(inode, 1);
644 }
645 
646 static const struct export_operations ntfs_export_ops = {
647 	.fh_to_dentry = ntfs_fh_to_dentry,
648 	.fh_to_parent = ntfs_fh_to_parent,
649 	.get_parent = ntfs3_get_parent,
650 	.commit_metadata = ntfs_nfs_commit_metadata,
651 };
652 
653 /*
654  * format_size_gb - Return Gb,Mb to print with "%u.%02u Gb".
655  */
656 static u32 format_size_gb(const u64 bytes, u32 *mb)
657 {
658 	/* Do simple right 30 bit shift of 64 bit value. */
659 	u64 kbytes = bytes >> 10;
660 	u32 kbytes32 = kbytes;
661 
662 	*mb = (100 * (kbytes32 & 0xfffff) + 0x7ffff) >> 20;
663 	if (*mb >= 100)
664 		*mb = 99;
665 
666 	return (kbytes32 >> 20) | (((u32)(kbytes >> 32)) << 12);
667 }
668 
669 static u32 true_sectors_per_clst(const struct NTFS_BOOT *boot)
670 {
671 	return boot->sectors_per_clusters <= 0x80
672 		       ? boot->sectors_per_clusters
673 		       : (1u << (0 - boot->sectors_per_clusters));
674 }
675 
676 /*
677  * ntfs_init_from_boot - Init internal info from on-disk boot sector.
678  */
679 static int ntfs_init_from_boot(struct super_block *sb, u32 sector_size,
680 			       u64 dev_size)
681 {
682 	struct ntfs_sb_info *sbi = sb->s_fs_info;
683 	int err;
684 	u32 mb, gb, boot_sector_size, sct_per_clst, record_size;
685 	u64 sectors, clusters, mlcn, mlcn2;
686 	struct NTFS_BOOT *boot;
687 	struct buffer_head *bh;
688 	struct MFT_REC *rec;
689 	u16 fn, ao;
690 
691 	sbi->volume.blocks = dev_size >> PAGE_SHIFT;
692 
693 	bh = ntfs_bread(sb, 0);
694 	if (!bh)
695 		return -EIO;
696 
697 	err = -EINVAL;
698 	boot = (struct NTFS_BOOT *)bh->b_data;
699 
700 	if (memcmp(boot->system_id, "NTFS    ", sizeof("NTFS    ") - 1))
701 		goto out;
702 
703 	/* 0x55AA is not mandaroty. Thanks Maxim Suhanov*/
704 	/*if (0x55 != boot->boot_magic[0] || 0xAA != boot->boot_magic[1])
705 	 *	goto out;
706 	 */
707 
708 	boot_sector_size = (u32)boot->bytes_per_sector[1] << 8;
709 	if (boot->bytes_per_sector[0] || boot_sector_size < SECTOR_SIZE ||
710 	    !is_power_of_2(boot_sector_size)) {
711 		goto out;
712 	}
713 
714 	/* cluster size: 512, 1K, 2K, 4K, ... 2M */
715 	sct_per_clst = true_sectors_per_clst(boot);
716 	if (!is_power_of_2(sct_per_clst))
717 		goto out;
718 
719 	mlcn = le64_to_cpu(boot->mft_clst);
720 	mlcn2 = le64_to_cpu(boot->mft2_clst);
721 	sectors = le64_to_cpu(boot->sectors_per_volume);
722 
723 	if (mlcn * sct_per_clst >= sectors)
724 		goto out;
725 
726 	if (mlcn2 * sct_per_clst >= sectors)
727 		goto out;
728 
729 	/* Check MFT record size. */
730 	if ((boot->record_size < 0 &&
731 	     SECTOR_SIZE > (2U << (-boot->record_size))) ||
732 	    (boot->record_size >= 0 && !is_power_of_2(boot->record_size))) {
733 		goto out;
734 	}
735 
736 	/* Check index record size. */
737 	if ((boot->index_size < 0 &&
738 	     SECTOR_SIZE > (2U << (-boot->index_size))) ||
739 	    (boot->index_size >= 0 && !is_power_of_2(boot->index_size))) {
740 		goto out;
741 	}
742 
743 	sbi->volume.size = sectors * boot_sector_size;
744 
745 	gb = format_size_gb(sbi->volume.size + boot_sector_size, &mb);
746 
747 	/*
748 	 * - Volume formatted and mounted with the same sector size.
749 	 * - Volume formatted 4K and mounted as 512.
750 	 * - Volume formatted 512 and mounted as 4K.
751 	 */
752 	if (boot_sector_size != sector_size) {
753 		ntfs_warn(
754 			sb,
755 			"Different NTFS' sector size (%u) and media sector size (%u)",
756 			boot_sector_size, sector_size);
757 		dev_size += sector_size - 1;
758 	}
759 
760 	sbi->cluster_size = boot_sector_size * sct_per_clst;
761 	sbi->cluster_bits = blksize_bits(sbi->cluster_size);
762 
763 	sbi->mft.lbo = mlcn << sbi->cluster_bits;
764 	sbi->mft.lbo2 = mlcn2 << sbi->cluster_bits;
765 
766 	/* Compare boot's cluster and sector. */
767 	if (sbi->cluster_size < boot_sector_size)
768 		goto out;
769 
770 	/* Compare boot's cluster and media sector. */
771 	if (sbi->cluster_size < sector_size) {
772 		/* No way to use ntfs_get_block in this case. */
773 		ntfs_err(
774 			sb,
775 			"Failed to mount 'cause NTFS's cluster size (%u) is less than media sector size (%u)",
776 			sbi->cluster_size, sector_size);
777 		goto out;
778 	}
779 
780 	sbi->cluster_mask = sbi->cluster_size - 1;
781 	sbi->cluster_mask_inv = ~(u64)sbi->cluster_mask;
782 	sbi->record_size = record_size = boot->record_size < 0
783 						 ? 1 << (-boot->record_size)
784 						 : (u32)boot->record_size
785 							   << sbi->cluster_bits;
786 
787 	if (record_size > MAXIMUM_BYTES_PER_MFT)
788 		goto out;
789 
790 	sbi->record_bits = blksize_bits(record_size);
791 	sbi->attr_size_tr = (5 * record_size >> 4); // ~320 bytes
792 
793 	sbi->max_bytes_per_attr =
794 		record_size - ALIGN(MFTRECORD_FIXUP_OFFSET_1, 8) -
795 		ALIGN(((record_size >> SECTOR_SHIFT) * sizeof(short)), 8) -
796 		ALIGN(sizeof(enum ATTR_TYPE), 8);
797 
798 	sbi->index_size = boot->index_size < 0
799 				  ? 1u << (-boot->index_size)
800 				  : (u32)boot->index_size << sbi->cluster_bits;
801 
802 	sbi->volume.ser_num = le64_to_cpu(boot->serial_num);
803 
804 	/* Warning if RAW volume. */
805 	if (dev_size < sbi->volume.size + boot_sector_size) {
806 		u32 mb0, gb0;
807 
808 		gb0 = format_size_gb(dev_size, &mb0);
809 		ntfs_warn(
810 			sb,
811 			"RAW NTFS volume: Filesystem size %u.%02u Gb > volume size %u.%02u Gb. Mount in read-only",
812 			gb, mb, gb0, mb0);
813 		sb->s_flags |= SB_RDONLY;
814 	}
815 
816 	clusters = sbi->volume.size >> sbi->cluster_bits;
817 #ifndef CONFIG_NTFS3_64BIT_CLUSTER
818 	/* 32 bits per cluster. */
819 	if (clusters >> 32) {
820 		ntfs_notice(
821 			sb,
822 			"NTFS %u.%02u Gb is too big to use 32 bits per cluster",
823 			gb, mb);
824 		goto out;
825 	}
826 #elif BITS_PER_LONG < 64
827 #error "CONFIG_NTFS3_64BIT_CLUSTER incompatible in 32 bit OS"
828 #endif
829 
830 	sbi->used.bitmap.nbits = clusters;
831 
832 	rec = kzalloc(record_size, GFP_NOFS);
833 	if (!rec) {
834 		err = -ENOMEM;
835 		goto out;
836 	}
837 
838 	sbi->new_rec = rec;
839 	rec->rhdr.sign = NTFS_FILE_SIGNATURE;
840 	rec->rhdr.fix_off = cpu_to_le16(MFTRECORD_FIXUP_OFFSET_1);
841 	fn = (sbi->record_size >> SECTOR_SHIFT) + 1;
842 	rec->rhdr.fix_num = cpu_to_le16(fn);
843 	ao = ALIGN(MFTRECORD_FIXUP_OFFSET_1 + sizeof(short) * fn, 8);
844 	rec->attr_off = cpu_to_le16(ao);
845 	rec->used = cpu_to_le32(ao + ALIGN(sizeof(enum ATTR_TYPE), 8));
846 	rec->total = cpu_to_le32(sbi->record_size);
847 	((struct ATTRIB *)Add2Ptr(rec, ao))->type = ATTR_END;
848 
849 	sb_set_blocksize(sb, min_t(u32, sbi->cluster_size, PAGE_SIZE));
850 
851 	sbi->block_mask = sb->s_blocksize - 1;
852 	sbi->blocks_per_cluster = sbi->cluster_size >> sb->s_blocksize_bits;
853 	sbi->volume.blocks = sbi->volume.size >> sb->s_blocksize_bits;
854 
855 	/* Maximum size for normal files. */
856 	sbi->maxbytes = (clusters << sbi->cluster_bits) - 1;
857 
858 #ifdef CONFIG_NTFS3_64BIT_CLUSTER
859 	if (clusters >= (1ull << (64 - sbi->cluster_bits)))
860 		sbi->maxbytes = -1;
861 	sbi->maxbytes_sparse = -1;
862 	sb->s_maxbytes = MAX_LFS_FILESIZE;
863 #else
864 	/* Maximum size for sparse file. */
865 	sbi->maxbytes_sparse = (1ull << (sbi->cluster_bits + 32)) - 1;
866 	sb->s_maxbytes = 0xFFFFFFFFull << sbi->cluster_bits;
867 #endif
868 
869 	err = 0;
870 
871 out:
872 	brelse(bh);
873 
874 	return err;
875 }
876 
877 /*
878  * ntfs_fill_super - Try to mount.
879  */
880 static int ntfs_fill_super(struct super_block *sb, struct fs_context *fc)
881 {
882 	int err;
883 	struct ntfs_sb_info *sbi = sb->s_fs_info;
884 	struct block_device *bdev = sb->s_bdev;
885 	struct inode *inode;
886 	struct ntfs_inode *ni;
887 	size_t i, tt;
888 	CLST vcn, lcn, len;
889 	struct ATTRIB *attr;
890 	const struct VOLUME_INFO *info;
891 	u32 idx, done, bytes;
892 	struct ATTR_DEF_ENTRY *t;
893 	u16 *shared;
894 	struct MFT_REF ref;
895 
896 	ref.high = 0;
897 
898 	sbi->sb = sb;
899 	sb->s_flags |= SB_NODIRATIME;
900 	sb->s_magic = 0x7366746e; // "ntfs"
901 	sb->s_op = &ntfs_sops;
902 	sb->s_export_op = &ntfs_export_ops;
903 	sb->s_time_gran = NTFS_TIME_GRAN; // 100 nsec
904 	sb->s_xattr = ntfs_xattr_handlers;
905 
906 	sbi->options->nls = ntfs_load_nls(sbi->options->nls_name);
907 	if (IS_ERR(sbi->options->nls)) {
908 		sbi->options->nls = NULL;
909 		errorf(fc, "Cannot load nls %s", sbi->options->nls_name);
910 		err = -EINVAL;
911 		goto out;
912 	}
913 
914 	if (bdev_max_discard_sectors(bdev) && bdev_discard_granularity(bdev)) {
915 		sbi->discard_granularity = bdev_discard_granularity(bdev);
916 		sbi->discard_granularity_mask_inv =
917 			~(u64)(sbi->discard_granularity - 1);
918 	}
919 
920 	/* Parse boot. */
921 	err = ntfs_init_from_boot(sb, bdev_logical_block_size(bdev),
922 				  bdev_nr_bytes(bdev));
923 	if (err)
924 		goto out;
925 
926 	/*
927 	 * Load $Volume. This should be done before $LogFile
928 	 * 'cause 'sbi->volume.ni' is used 'ntfs_set_state'.
929 	 */
930 	ref.low = cpu_to_le32(MFT_REC_VOL);
931 	ref.seq = cpu_to_le16(MFT_REC_VOL);
932 	inode = ntfs_iget5(sb, &ref, &NAME_VOLUME);
933 	if (IS_ERR(inode)) {
934 		ntfs_err(sb, "Failed to load $Volume.");
935 		err = PTR_ERR(inode);
936 		goto out;
937 	}
938 
939 	ni = ntfs_i(inode);
940 
941 	/* Load and save label (not necessary). */
942 	attr = ni_find_attr(ni, NULL, NULL, ATTR_LABEL, NULL, 0, NULL, NULL);
943 
944 	if (!attr) {
945 		/* It is ok if no ATTR_LABEL */
946 	} else if (!attr->non_res && !is_attr_ext(attr)) {
947 		/* $AttrDef allows labels to be up to 128 symbols. */
948 		err = utf16s_to_utf8s(resident_data(attr),
949 				      le32_to_cpu(attr->res.data_size) >> 1,
950 				      UTF16_LITTLE_ENDIAN, sbi->volume.label,
951 				      sizeof(sbi->volume.label));
952 		if (err < 0)
953 			sbi->volume.label[0] = 0;
954 	} else {
955 		/* Should we break mounting here? */
956 		//err = -EINVAL;
957 		//goto put_inode_out;
958 	}
959 
960 	attr = ni_find_attr(ni, attr, NULL, ATTR_VOL_INFO, NULL, 0, NULL, NULL);
961 	if (!attr || is_attr_ext(attr)) {
962 		err = -EINVAL;
963 		goto put_inode_out;
964 	}
965 
966 	info = resident_data_ex(attr, SIZEOF_ATTRIBUTE_VOLUME_INFO);
967 	if (!info) {
968 		err = -EINVAL;
969 		goto put_inode_out;
970 	}
971 
972 	sbi->volume.major_ver = info->major_ver;
973 	sbi->volume.minor_ver = info->minor_ver;
974 	sbi->volume.flags = info->flags;
975 	sbi->volume.ni = ni;
976 
977 	/* Load $MFTMirr to estimate recs_mirr. */
978 	ref.low = cpu_to_le32(MFT_REC_MIRR);
979 	ref.seq = cpu_to_le16(MFT_REC_MIRR);
980 	inode = ntfs_iget5(sb, &ref, &NAME_MIRROR);
981 	if (IS_ERR(inode)) {
982 		ntfs_err(sb, "Failed to load $MFTMirr.");
983 		err = PTR_ERR(inode);
984 		goto out;
985 	}
986 
987 	sbi->mft.recs_mirr =
988 		ntfs_up_cluster(sbi, inode->i_size) >> sbi->record_bits;
989 
990 	iput(inode);
991 
992 	/* Load LogFile to replay. */
993 	ref.low = cpu_to_le32(MFT_REC_LOG);
994 	ref.seq = cpu_to_le16(MFT_REC_LOG);
995 	inode = ntfs_iget5(sb, &ref, &NAME_LOGFILE);
996 	if (IS_ERR(inode)) {
997 		ntfs_err(sb, "Failed to load \x24LogFile.");
998 		err = PTR_ERR(inode);
999 		goto out;
1000 	}
1001 
1002 	ni = ntfs_i(inode);
1003 
1004 	err = ntfs_loadlog_and_replay(ni, sbi);
1005 	if (err)
1006 		goto put_inode_out;
1007 
1008 	iput(inode);
1009 
1010 	if (sbi->flags & NTFS_FLAGS_NEED_REPLAY) {
1011 		if (!sb_rdonly(sb)) {
1012 			ntfs_warn(sb,
1013 				  "failed to replay log file. Can't mount rw!");
1014 			err = -EINVAL;
1015 			goto out;
1016 		}
1017 	} else if (sbi->volume.flags & VOLUME_FLAG_DIRTY) {
1018 		if (!sb_rdonly(sb) && !sbi->options->force) {
1019 			ntfs_warn(
1020 				sb,
1021 				"volume is dirty and \"force\" flag is not set!");
1022 			err = -EINVAL;
1023 			goto out;
1024 		}
1025 	}
1026 
1027 	/* Load $MFT. */
1028 	ref.low = cpu_to_le32(MFT_REC_MFT);
1029 	ref.seq = cpu_to_le16(1);
1030 
1031 	inode = ntfs_iget5(sb, &ref, &NAME_MFT);
1032 	if (IS_ERR(inode)) {
1033 		ntfs_err(sb, "Failed to load $MFT.");
1034 		err = PTR_ERR(inode);
1035 		goto out;
1036 	}
1037 
1038 	ni = ntfs_i(inode);
1039 
1040 	sbi->mft.used = ni->i_valid >> sbi->record_bits;
1041 	tt = inode->i_size >> sbi->record_bits;
1042 	sbi->mft.next_free = MFT_REC_USER;
1043 
1044 	err = wnd_init(&sbi->mft.bitmap, sb, tt);
1045 	if (err)
1046 		goto put_inode_out;
1047 
1048 	err = ni_load_all_mi(ni);
1049 	if (err)
1050 		goto put_inode_out;
1051 
1052 	sbi->mft.ni = ni;
1053 
1054 	/* Load $BadClus. */
1055 	ref.low = cpu_to_le32(MFT_REC_BADCLUST);
1056 	ref.seq = cpu_to_le16(MFT_REC_BADCLUST);
1057 	inode = ntfs_iget5(sb, &ref, &NAME_BADCLUS);
1058 	if (IS_ERR(inode)) {
1059 		ntfs_err(sb, "Failed to load $BadClus.");
1060 		err = PTR_ERR(inode);
1061 		goto out;
1062 	}
1063 
1064 	ni = ntfs_i(inode);
1065 
1066 	for (i = 0; run_get_entry(&ni->file.run, i, &vcn, &lcn, &len); i++) {
1067 		if (lcn == SPARSE_LCN)
1068 			continue;
1069 
1070 		if (!sbi->bad_clusters)
1071 			ntfs_notice(sb, "Volume contains bad blocks");
1072 
1073 		sbi->bad_clusters += len;
1074 	}
1075 
1076 	iput(inode);
1077 
1078 	/* Load $Bitmap. */
1079 	ref.low = cpu_to_le32(MFT_REC_BITMAP);
1080 	ref.seq = cpu_to_le16(MFT_REC_BITMAP);
1081 	inode = ntfs_iget5(sb, &ref, &NAME_BITMAP);
1082 	if (IS_ERR(inode)) {
1083 		ntfs_err(sb, "Failed to load $Bitmap.");
1084 		err = PTR_ERR(inode);
1085 		goto out;
1086 	}
1087 
1088 #ifndef CONFIG_NTFS3_64BIT_CLUSTER
1089 	if (inode->i_size >> 32) {
1090 		err = -EINVAL;
1091 		goto put_inode_out;
1092 	}
1093 #endif
1094 
1095 	/* Check bitmap boundary. */
1096 	tt = sbi->used.bitmap.nbits;
1097 	if (inode->i_size < bitmap_size(tt)) {
1098 		err = -EINVAL;
1099 		goto put_inode_out;
1100 	}
1101 
1102 	/* Not necessary. */
1103 	sbi->used.bitmap.set_tail = true;
1104 	err = wnd_init(&sbi->used.bitmap, sb, tt);
1105 	if (err)
1106 		goto put_inode_out;
1107 
1108 	iput(inode);
1109 
1110 	/* Compute the MFT zone. */
1111 	err = ntfs_refresh_zone(sbi);
1112 	if (err)
1113 		goto out;
1114 
1115 	/* Load $AttrDef. */
1116 	ref.low = cpu_to_le32(MFT_REC_ATTR);
1117 	ref.seq = cpu_to_le16(MFT_REC_ATTR);
1118 	inode = ntfs_iget5(sb, &ref, &NAME_ATTRDEF);
1119 	if (IS_ERR(inode)) {
1120 		ntfs_err(sb, "Failed to load $AttrDef -> %d", err);
1121 		err = PTR_ERR(inode);
1122 		goto out;
1123 	}
1124 
1125 	if (inode->i_size < sizeof(struct ATTR_DEF_ENTRY)) {
1126 		err = -EINVAL;
1127 		goto put_inode_out;
1128 	}
1129 	bytes = inode->i_size;
1130 	sbi->def_table = t = kmalloc(bytes, GFP_NOFS);
1131 	if (!t) {
1132 		err = -ENOMEM;
1133 		goto put_inode_out;
1134 	}
1135 
1136 	for (done = idx = 0; done < bytes; done += PAGE_SIZE, idx++) {
1137 		unsigned long tail = bytes - done;
1138 		struct page *page = ntfs_map_page(inode->i_mapping, idx);
1139 
1140 		if (IS_ERR(page)) {
1141 			err = PTR_ERR(page);
1142 			goto put_inode_out;
1143 		}
1144 		memcpy(Add2Ptr(t, done), page_address(page),
1145 		       min(PAGE_SIZE, tail));
1146 		ntfs_unmap_page(page);
1147 
1148 		if (!idx && ATTR_STD != t->type) {
1149 			err = -EINVAL;
1150 			goto put_inode_out;
1151 		}
1152 	}
1153 
1154 	t += 1;
1155 	sbi->def_entries = 1;
1156 	done = sizeof(struct ATTR_DEF_ENTRY);
1157 	sbi->reparse.max_size = MAXIMUM_REPARSE_DATA_BUFFER_SIZE;
1158 	sbi->ea_max_size = 0x10000; /* default formatter value */
1159 
1160 	while (done + sizeof(struct ATTR_DEF_ENTRY) <= bytes) {
1161 		u32 t32 = le32_to_cpu(t->type);
1162 		u64 sz = le64_to_cpu(t->max_sz);
1163 
1164 		if ((t32 & 0xF) || le32_to_cpu(t[-1].type) >= t32)
1165 			break;
1166 
1167 		if (t->type == ATTR_REPARSE)
1168 			sbi->reparse.max_size = sz;
1169 		else if (t->type == ATTR_EA)
1170 			sbi->ea_max_size = sz;
1171 
1172 		done += sizeof(struct ATTR_DEF_ENTRY);
1173 		t += 1;
1174 		sbi->def_entries += 1;
1175 	}
1176 	iput(inode);
1177 
1178 	/* Load $UpCase. */
1179 	ref.low = cpu_to_le32(MFT_REC_UPCASE);
1180 	ref.seq = cpu_to_le16(MFT_REC_UPCASE);
1181 	inode = ntfs_iget5(sb, &ref, &NAME_UPCASE);
1182 	if (IS_ERR(inode)) {
1183 		ntfs_err(sb, "Failed to load $UpCase.");
1184 		err = PTR_ERR(inode);
1185 		goto out;
1186 	}
1187 
1188 	if (inode->i_size != 0x10000 * sizeof(short)) {
1189 		err = -EINVAL;
1190 		goto put_inode_out;
1191 	}
1192 
1193 	for (idx = 0; idx < (0x10000 * sizeof(short) >> PAGE_SHIFT); idx++) {
1194 		const __le16 *src;
1195 		u16 *dst = Add2Ptr(sbi->upcase, idx << PAGE_SHIFT);
1196 		struct page *page = ntfs_map_page(inode->i_mapping, idx);
1197 
1198 		if (IS_ERR(page)) {
1199 			err = PTR_ERR(page);
1200 			goto put_inode_out;
1201 		}
1202 
1203 		src = page_address(page);
1204 
1205 #ifdef __BIG_ENDIAN
1206 		for (i = 0; i < PAGE_SIZE / sizeof(u16); i++)
1207 			*dst++ = le16_to_cpu(*src++);
1208 #else
1209 		memcpy(dst, src, PAGE_SIZE);
1210 #endif
1211 		ntfs_unmap_page(page);
1212 	}
1213 
1214 	shared = ntfs_set_shared(sbi->upcase, 0x10000 * sizeof(short));
1215 	if (shared && sbi->upcase != shared) {
1216 		kvfree(sbi->upcase);
1217 		sbi->upcase = shared;
1218 	}
1219 
1220 	iput(inode);
1221 
1222 	if (is_ntfs3(sbi)) {
1223 		/* Load $Secure. */
1224 		err = ntfs_security_init(sbi);
1225 		if (err)
1226 			goto out;
1227 
1228 		/* Load $Extend. */
1229 		err = ntfs_extend_init(sbi);
1230 		if (err)
1231 			goto load_root;
1232 
1233 		/* Load $Extend\$Reparse. */
1234 		err = ntfs_reparse_init(sbi);
1235 		if (err)
1236 			goto load_root;
1237 
1238 		/* Load $Extend\$ObjId. */
1239 		err = ntfs_objid_init(sbi);
1240 		if (err)
1241 			goto load_root;
1242 	}
1243 
1244 load_root:
1245 	/* Load root. */
1246 	ref.low = cpu_to_le32(MFT_REC_ROOT);
1247 	ref.seq = cpu_to_le16(MFT_REC_ROOT);
1248 	inode = ntfs_iget5(sb, &ref, &NAME_ROOT);
1249 	if (IS_ERR(inode)) {
1250 		ntfs_err(sb, "Failed to load root.");
1251 		err = PTR_ERR(inode);
1252 		goto out;
1253 	}
1254 
1255 	sb->s_root = d_make_root(inode);
1256 	if (!sb->s_root) {
1257 		err = -ENOMEM;
1258 		goto put_inode_out;
1259 	}
1260 
1261 	fc->fs_private = NULL;
1262 
1263 	return 0;
1264 
1265 put_inode_out:
1266 	iput(inode);
1267 out:
1268 	/*
1269 	 * Free resources here.
1270 	 * ntfs_fs_free will be called with fc->s_fs_info = NULL
1271 	 */
1272 	put_ntfs(sbi);
1273 	sb->s_fs_info = NULL;
1274 
1275 	return err;
1276 }
1277 
1278 void ntfs_unmap_meta(struct super_block *sb, CLST lcn, CLST len)
1279 {
1280 	struct ntfs_sb_info *sbi = sb->s_fs_info;
1281 	struct block_device *bdev = sb->s_bdev;
1282 	sector_t devblock = (u64)lcn * sbi->blocks_per_cluster;
1283 	unsigned long blocks = (u64)len * sbi->blocks_per_cluster;
1284 	unsigned long cnt = 0;
1285 	unsigned long limit = global_zone_page_state(NR_FREE_PAGES)
1286 			      << (PAGE_SHIFT - sb->s_blocksize_bits);
1287 
1288 	if (limit >= 0x2000)
1289 		limit -= 0x1000;
1290 	else if (limit < 32)
1291 		limit = 32;
1292 	else
1293 		limit >>= 1;
1294 
1295 	while (blocks--) {
1296 		clean_bdev_aliases(bdev, devblock++, 1);
1297 		if (cnt++ >= limit) {
1298 			sync_blockdev(bdev);
1299 			cnt = 0;
1300 		}
1301 	}
1302 }
1303 
1304 /*
1305  * ntfs_discard - Issue a discard request (trim for SSD).
1306  */
1307 int ntfs_discard(struct ntfs_sb_info *sbi, CLST lcn, CLST len)
1308 {
1309 	int err;
1310 	u64 lbo, bytes, start, end;
1311 	struct super_block *sb;
1312 
1313 	if (sbi->used.next_free_lcn == lcn + len)
1314 		sbi->used.next_free_lcn = lcn;
1315 
1316 	if (sbi->flags & NTFS_FLAGS_NODISCARD)
1317 		return -EOPNOTSUPP;
1318 
1319 	if (!sbi->options->discard)
1320 		return -EOPNOTSUPP;
1321 
1322 	lbo = (u64)lcn << sbi->cluster_bits;
1323 	bytes = (u64)len << sbi->cluster_bits;
1324 
1325 	/* Align up 'start' on discard_granularity. */
1326 	start = (lbo + sbi->discard_granularity - 1) &
1327 		sbi->discard_granularity_mask_inv;
1328 	/* Align down 'end' on discard_granularity. */
1329 	end = (lbo + bytes) & sbi->discard_granularity_mask_inv;
1330 
1331 	sb = sbi->sb;
1332 	if (start >= end)
1333 		return 0;
1334 
1335 	err = blkdev_issue_discard(sb->s_bdev, start >> 9, (end - start) >> 9,
1336 				   GFP_NOFS);
1337 
1338 	if (err == -EOPNOTSUPP)
1339 		sbi->flags |= NTFS_FLAGS_NODISCARD;
1340 
1341 	return err;
1342 }
1343 
1344 static int ntfs_fs_get_tree(struct fs_context *fc)
1345 {
1346 	return get_tree_bdev(fc, ntfs_fill_super);
1347 }
1348 
1349 /*
1350  * ntfs_fs_free - Free fs_context.
1351  *
1352  * Note that this will be called after fill_super and reconfigure
1353  * even when they pass. So they have to take pointers if they pass.
1354  */
1355 static void ntfs_fs_free(struct fs_context *fc)
1356 {
1357 	struct ntfs_mount_options *opts = fc->fs_private;
1358 	struct ntfs_sb_info *sbi = fc->s_fs_info;
1359 
1360 	if (sbi)
1361 		put_ntfs(sbi);
1362 
1363 	if (opts)
1364 		put_mount_options(opts);
1365 }
1366 
1367 static const struct fs_context_operations ntfs_context_ops = {
1368 	.parse_param	= ntfs_fs_parse_param,
1369 	.get_tree	= ntfs_fs_get_tree,
1370 	.reconfigure	= ntfs_fs_reconfigure,
1371 	.free		= ntfs_fs_free,
1372 };
1373 
1374 /*
1375  * ntfs_init_fs_context - Initialize spi and opts
1376  *
1377  * This will called when mount/remount. We will first initiliaze
1378  * options so that if remount we can use just that.
1379  */
1380 static int ntfs_init_fs_context(struct fs_context *fc)
1381 {
1382 	struct ntfs_mount_options *opts;
1383 	struct ntfs_sb_info *sbi;
1384 
1385 	opts = kzalloc(sizeof(struct ntfs_mount_options), GFP_NOFS);
1386 	if (!opts)
1387 		return -ENOMEM;
1388 
1389 	/* Default options. */
1390 	opts->fs_uid = current_uid();
1391 	opts->fs_gid = current_gid();
1392 	opts->fs_fmask_inv = ~current_umask();
1393 	opts->fs_dmask_inv = ~current_umask();
1394 
1395 	if (fc->purpose == FS_CONTEXT_FOR_RECONFIGURE)
1396 		goto ok;
1397 
1398 	sbi = kzalloc(sizeof(struct ntfs_sb_info), GFP_NOFS);
1399 	if (!sbi)
1400 		goto free_opts;
1401 
1402 	sbi->upcase = kvmalloc(0x10000 * sizeof(short), GFP_KERNEL);
1403 	if (!sbi->upcase)
1404 		goto free_sbi;
1405 
1406 	ratelimit_state_init(&sbi->msg_ratelimit, DEFAULT_RATELIMIT_INTERVAL,
1407 			     DEFAULT_RATELIMIT_BURST);
1408 
1409 	mutex_init(&sbi->compress.mtx_lznt);
1410 #ifdef CONFIG_NTFS3_LZX_XPRESS
1411 	mutex_init(&sbi->compress.mtx_xpress);
1412 	mutex_init(&sbi->compress.mtx_lzx);
1413 #endif
1414 
1415 	sbi->options = opts;
1416 	fc->s_fs_info = sbi;
1417 ok:
1418 	fc->fs_private = opts;
1419 	fc->ops = &ntfs_context_ops;
1420 
1421 	return 0;
1422 free_sbi:
1423 	kfree(sbi);
1424 free_opts:
1425 	kfree(opts);
1426 	return -ENOMEM;
1427 }
1428 
1429 // clang-format off
1430 static struct file_system_type ntfs_fs_type = {
1431 	.owner			= THIS_MODULE,
1432 	.name			= "ntfs3",
1433 	.init_fs_context	= ntfs_init_fs_context,
1434 	.parameters		= ntfs_fs_parameters,
1435 	.kill_sb		= kill_block_super,
1436 	.fs_flags		= FS_REQUIRES_DEV | FS_ALLOW_IDMAP,
1437 };
1438 // clang-format on
1439 
1440 static int __init init_ntfs_fs(void)
1441 {
1442 	int err;
1443 
1444 	pr_info("ntfs3: Max link count %u\n", NTFS_LINK_MAX);
1445 
1446 	if (IS_ENABLED(CONFIG_NTFS3_FS_POSIX_ACL))
1447 		pr_info("ntfs3: Enabled Linux POSIX ACLs support\n");
1448 	if (IS_ENABLED(CONFIG_NTFS3_64BIT_CLUSTER))
1449 		pr_notice("ntfs3: Warning: Activated 64 bits per cluster. Windows does not support this\n");
1450 	if (IS_ENABLED(CONFIG_NTFS3_LZX_XPRESS))
1451 		pr_info("ntfs3: Read-only LZX/Xpress compression included\n");
1452 
1453 	err = ntfs3_init_bitmap();
1454 	if (err)
1455 		return err;
1456 
1457 	ntfs_inode_cachep = kmem_cache_create(
1458 		"ntfs_inode_cache", sizeof(struct ntfs_inode), 0,
1459 		(SLAB_RECLAIM_ACCOUNT | SLAB_MEM_SPREAD | SLAB_ACCOUNT),
1460 		init_once);
1461 	if (!ntfs_inode_cachep) {
1462 		err = -ENOMEM;
1463 		goto out1;
1464 	}
1465 
1466 	err = register_filesystem(&ntfs_fs_type);
1467 	if (err)
1468 		goto out;
1469 
1470 	return 0;
1471 out:
1472 	kmem_cache_destroy(ntfs_inode_cachep);
1473 out1:
1474 	ntfs3_exit_bitmap();
1475 	return err;
1476 }
1477 
1478 static void __exit exit_ntfs_fs(void)
1479 {
1480 	if (ntfs_inode_cachep) {
1481 		rcu_barrier();
1482 		kmem_cache_destroy(ntfs_inode_cachep);
1483 	}
1484 
1485 	unregister_filesystem(&ntfs_fs_type);
1486 	ntfs3_exit_bitmap();
1487 }
1488 
1489 MODULE_LICENSE("GPL");
1490 MODULE_DESCRIPTION("ntfs3 read/write filesystem");
1491 #ifdef CONFIG_NTFS3_FS_POSIX_ACL
1492 MODULE_INFO(behaviour, "Enabled Linux POSIX ACLs support");
1493 #endif
1494 #ifdef CONFIG_NTFS3_64BIT_CLUSTER
1495 MODULE_INFO(cluster, "Warning: Activated 64 bits per cluster. Windows does not support this");
1496 #endif
1497 #ifdef CONFIG_NTFS3_LZX_XPRESS
1498 MODULE_INFO(compression, "Read-only lzx/xpress compression included");
1499 #endif
1500 
1501 MODULE_AUTHOR("Konstantin Komarov");
1502 MODULE_ALIAS_FS("ntfs3");
1503 
1504 module_init(init_ntfs_fs);
1505 module_exit(exit_ntfs_fs);
1506