xref: /openbmc/linux/fs/ntfs3/super.c (revision 2fa5ebe3)
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  * ntfs allows up to 2^64 clusters per volume.
25  * It means you should use 64 bits lcn to operate with ntfs.
26  * Implementation of ntfs.sys uses only 32 bits lcn.
27  * Default ntfs3 uses 32 bits lcn too.
28  * ntfs3 built with CONFIG_NTFS3_64BIT_CLUSTER (ntfs3_64) uses 64 bits per lcn.
29  *
30  *
31  *     ntfs limits, cluster size is 4K (2^12)
32  * -----------------------------------------------------------------------------
33  * | Volume size   | Clusters | ntfs.sys | ntfs3  | ntfs3_64 | mkntfs | chkdsk |
34  * -----------------------------------------------------------------------------
35  * | < 16T, 2^44   |  < 2^32  |  yes     |  yes   |   yes    |  yes   |  yes   |
36  * | > 16T, 2^44   |  > 2^32  |  no      |  no    |   yes    |  yes   |  yes   |
37  * ----------------------------------------------------------|------------------
38  *
39  * To mount large volumes as ntfs one should use large cluster size (up to 2M)
40  * The maximum volume size in this case is 2^32 * 2^21 = 2^53 = 8P
41  *
42  *     ntfs limits, cluster size is 2M (2^31)
43  * -----------------------------------------------------------------------------
44  * | < 8P, 2^54    |  < 2^32  |  yes     |  yes   |   yes    |  yes   |  yes   |
45  * | > 8P, 2^54    |  > 2^32  |  no      |  no    |   yes    |  yes   |  yes   |
46  * ----------------------------------------------------------|------------------
47  *
48  */
49 
50 #include <linux/blkdev.h>
51 #include <linux/buffer_head.h>
52 #include <linux/exportfs.h>
53 #include <linux/fs.h>
54 #include <linux/fs_context.h>
55 #include <linux/fs_parser.h>
56 #include <linux/log2.h>
57 #include <linux/minmax.h>
58 #include <linux/module.h>
59 #include <linux/nls.h>
60 #include <linux/seq_file.h>
61 #include <linux/statfs.h>
62 
63 #include "debug.h"
64 #include "ntfs.h"
65 #include "ntfs_fs.h"
66 #ifdef CONFIG_NTFS3_LZX_XPRESS
67 #include "lib/lib.h"
68 #endif
69 
70 #ifdef CONFIG_PRINTK
71 /*
72  * ntfs_printk - Trace warnings/notices/errors.
73  *
74  * Thanks Joe Perches <joe@perches.com> for implementation
75  */
76 void ntfs_printk(const struct super_block *sb, const char *fmt, ...)
77 {
78 	struct va_format vaf;
79 	va_list args;
80 	int level;
81 	struct ntfs_sb_info *sbi = sb->s_fs_info;
82 
83 	/* Should we use different ratelimits for warnings/notices/errors? */
84 	if (!___ratelimit(&sbi->msg_ratelimit, "ntfs3"))
85 		return;
86 
87 	va_start(args, fmt);
88 
89 	level = printk_get_level(fmt);
90 	vaf.fmt = printk_skip_level(fmt);
91 	vaf.va = &args;
92 	printk("%c%cntfs3: %s: %pV\n", KERN_SOH_ASCII, level, sb->s_id, &vaf);
93 
94 	va_end(args);
95 }
96 
97 static char s_name_buf[512];
98 static atomic_t s_name_buf_cnt = ATOMIC_INIT(1); // 1 means 'free s_name_buf'.
99 
100 /*
101  * ntfs_inode_printk
102  *
103  * Print warnings/notices/errors about inode using name or inode number.
104  */
105 void ntfs_inode_printk(struct inode *inode, const char *fmt, ...)
106 {
107 	struct super_block *sb = inode->i_sb;
108 	struct ntfs_sb_info *sbi = sb->s_fs_info;
109 	char *name;
110 	va_list args;
111 	struct va_format vaf;
112 	int level;
113 
114 	if (!___ratelimit(&sbi->msg_ratelimit, "ntfs3"))
115 		return;
116 
117 	/* Use static allocated buffer, if possible. */
118 	name = atomic_dec_and_test(&s_name_buf_cnt)
119 		       ? s_name_buf
120 		       : kmalloc(sizeof(s_name_buf), GFP_NOFS);
121 
122 	if (name) {
123 		struct dentry *de = d_find_alias(inode);
124 		const u32 name_len = ARRAY_SIZE(s_name_buf) - 1;
125 
126 		if (de) {
127 			spin_lock(&de->d_lock);
128 			snprintf(name, name_len, " \"%s\"", de->d_name.name);
129 			spin_unlock(&de->d_lock);
130 			name[name_len] = 0; /* To be sure. */
131 		} else {
132 			name[0] = 0;
133 		}
134 		dput(de); /* Cocci warns if placed in branch "if (de)" */
135 	}
136 
137 	va_start(args, fmt);
138 
139 	level = printk_get_level(fmt);
140 	vaf.fmt = printk_skip_level(fmt);
141 	vaf.va = &args;
142 
143 	printk("%c%cntfs3: %s: ino=%lx,%s %pV\n", KERN_SOH_ASCII, level,
144 	       sb->s_id, inode->i_ino, name ? name : "", &vaf);
145 
146 	va_end(args);
147 
148 	atomic_inc(&s_name_buf_cnt);
149 	if (name != s_name_buf)
150 		kfree(name);
151 }
152 #endif
153 
154 /*
155  * Shared memory struct.
156  *
157  * On-disk ntfs's upcase table is created by ntfs formatter.
158  * 'upcase' table is 128K bytes of memory.
159  * We should read it into memory when mounting.
160  * Several ntfs volumes likely use the same 'upcase' table.
161  * It is good idea to share in-memory 'upcase' table between different volumes.
162  * Unfortunately winxp/vista/win7 use different upcase tables.
163  */
164 static DEFINE_SPINLOCK(s_shared_lock);
165 
166 static struct {
167 	void *ptr;
168 	u32 len;
169 	int cnt;
170 } s_shared[8];
171 
172 /*
173  * ntfs_set_shared
174  *
175  * Return:
176  * * @ptr - If pointer was saved in shared memory.
177  * * NULL - If pointer was not shared.
178  */
179 void *ntfs_set_shared(void *ptr, u32 bytes)
180 {
181 	void *ret = NULL;
182 	int i, j = -1;
183 
184 	spin_lock(&s_shared_lock);
185 	for (i = 0; i < ARRAY_SIZE(s_shared); i++) {
186 		if (!s_shared[i].cnt) {
187 			j = i;
188 		} else if (bytes == s_shared[i].len &&
189 			   !memcmp(s_shared[i].ptr, ptr, bytes)) {
190 			s_shared[i].cnt += 1;
191 			ret = s_shared[i].ptr;
192 			break;
193 		}
194 	}
195 
196 	if (!ret && j != -1) {
197 		s_shared[j].ptr = ptr;
198 		s_shared[j].len = bytes;
199 		s_shared[j].cnt = 1;
200 		ret = ptr;
201 	}
202 	spin_unlock(&s_shared_lock);
203 
204 	return ret;
205 }
206 
207 /*
208  * ntfs_put_shared
209  *
210  * Return:
211  * * @ptr - If pointer is not shared anymore.
212  * * NULL - If pointer is still shared.
213  */
214 void *ntfs_put_shared(void *ptr)
215 {
216 	void *ret = ptr;
217 	int i;
218 
219 	spin_lock(&s_shared_lock);
220 	for (i = 0; i < ARRAY_SIZE(s_shared); i++) {
221 		if (s_shared[i].cnt && s_shared[i].ptr == ptr) {
222 			if (--s_shared[i].cnt)
223 				ret = NULL;
224 			break;
225 		}
226 	}
227 	spin_unlock(&s_shared_lock);
228 
229 	return ret;
230 }
231 
232 static inline void put_mount_options(struct ntfs_mount_options *options)
233 {
234 	kfree(options->nls_name);
235 	unload_nls(options->nls);
236 	kfree(options);
237 }
238 
239 enum Opt {
240 	Opt_uid,
241 	Opt_gid,
242 	Opt_umask,
243 	Opt_dmask,
244 	Opt_fmask,
245 	Opt_immutable,
246 	Opt_discard,
247 	Opt_force,
248 	Opt_sparse,
249 	Opt_nohidden,
250 	Opt_hide_dot_files,
251 	Opt_windows_names,
252 	Opt_showmeta,
253 	Opt_acl,
254 	Opt_iocharset,
255 	Opt_prealloc,
256 	Opt_noacsrules,
257 	Opt_nocase,
258 	Opt_err,
259 };
260 
261 static const struct fs_parameter_spec ntfs_fs_parameters[] = {
262 	fsparam_u32("uid",			Opt_uid),
263 	fsparam_u32("gid",			Opt_gid),
264 	fsparam_u32oct("umask",			Opt_umask),
265 	fsparam_u32oct("dmask",			Opt_dmask),
266 	fsparam_u32oct("fmask",			Opt_fmask),
267 	fsparam_flag_no("sys_immutable",	Opt_immutable),
268 	fsparam_flag_no("discard",		Opt_discard),
269 	fsparam_flag_no("force",		Opt_force),
270 	fsparam_flag_no("sparse",		Opt_sparse),
271 	fsparam_flag_no("hidden",		Opt_nohidden),
272 	fsparam_flag_no("hide_dot_files",	Opt_hide_dot_files),
273 	fsparam_flag_no("windows_names",	Opt_windows_names),
274 	fsparam_flag_no("acl",			Opt_acl),
275 	fsparam_flag_no("showmeta",		Opt_showmeta),
276 	fsparam_flag_no("prealloc",		Opt_prealloc),
277 	fsparam_flag_no("acsrules",		Opt_noacsrules),
278 	fsparam_flag_no("nocase",		Opt_nocase),
279 	fsparam_string("iocharset",		Opt_iocharset),
280 	{}
281 };
282 
283 /*
284  * Load nls table or if @nls is utf8 then return NULL.
285  */
286 static struct nls_table *ntfs_load_nls(char *nls)
287 {
288 	struct nls_table *ret;
289 
290 	if (!nls)
291 		nls = CONFIG_NLS_DEFAULT;
292 
293 	if (strcmp(nls, "utf8") == 0)
294 		return NULL;
295 
296 	if (strcmp(nls, CONFIG_NLS_DEFAULT) == 0)
297 		return load_nls_default();
298 
299 	ret = load_nls(nls);
300 	if (ret)
301 		return ret;
302 
303 	return ERR_PTR(-EINVAL);
304 }
305 
306 static int ntfs_fs_parse_param(struct fs_context *fc,
307 			       struct fs_parameter *param)
308 {
309 	struct ntfs_mount_options *opts = fc->fs_private;
310 	struct fs_parse_result result;
311 	int opt;
312 
313 	opt = fs_parse(fc, ntfs_fs_parameters, param, &result);
314 	if (opt < 0)
315 		return opt;
316 
317 	switch (opt) {
318 	case Opt_uid:
319 		opts->fs_uid = make_kuid(current_user_ns(), result.uint_32);
320 		if (!uid_valid(opts->fs_uid))
321 			return invalf(fc, "ntfs3: Invalid value for uid.");
322 		break;
323 	case Opt_gid:
324 		opts->fs_gid = make_kgid(current_user_ns(), result.uint_32);
325 		if (!gid_valid(opts->fs_gid))
326 			return invalf(fc, "ntfs3: Invalid value for gid.");
327 		break;
328 	case Opt_umask:
329 		if (result.uint_32 & ~07777)
330 			return invalf(fc, "ntfs3: Invalid value for umask.");
331 		opts->fs_fmask_inv = ~result.uint_32;
332 		opts->fs_dmask_inv = ~result.uint_32;
333 		opts->fmask = 1;
334 		opts->dmask = 1;
335 		break;
336 	case Opt_dmask:
337 		if (result.uint_32 & ~07777)
338 			return invalf(fc, "ntfs3: Invalid value for dmask.");
339 		opts->fs_dmask_inv = ~result.uint_32;
340 		opts->dmask = 1;
341 		break;
342 	case Opt_fmask:
343 		if (result.uint_32 & ~07777)
344 			return invalf(fc, "ntfs3: Invalid value for fmask.");
345 		opts->fs_fmask_inv = ~result.uint_32;
346 		opts->fmask = 1;
347 		break;
348 	case Opt_immutable:
349 		opts->sys_immutable = result.negated ? 0 : 1;
350 		break;
351 	case Opt_discard:
352 		opts->discard = result.negated ? 0 : 1;
353 		break;
354 	case Opt_force:
355 		opts->force = result.negated ? 0 : 1;
356 		break;
357 	case Opt_sparse:
358 		opts->sparse = result.negated ? 0 : 1;
359 		break;
360 	case Opt_nohidden:
361 		opts->nohidden = result.negated ? 1 : 0;
362 		break;
363 	case Opt_hide_dot_files:
364 		opts->hide_dot_files = result.negated ? 0 : 1;
365 		break;
366 	case Opt_windows_names:
367 		opts->windows_names = result.negated ? 0 : 1;
368 		break;
369 	case Opt_acl:
370 		if (!result.negated)
371 #ifdef CONFIG_NTFS3_FS_POSIX_ACL
372 			fc->sb_flags |= SB_POSIXACL;
373 #else
374 			return invalf(fc, "ntfs3: Support for ACL not compiled in!");
375 #endif
376 		else
377 			fc->sb_flags &= ~SB_POSIXACL;
378 		break;
379 	case Opt_showmeta:
380 		opts->showmeta = result.negated ? 0 : 1;
381 		break;
382 	case Opt_iocharset:
383 		kfree(opts->nls_name);
384 		opts->nls_name = param->string;
385 		param->string = NULL;
386 		break;
387 	case Opt_prealloc:
388 		opts->prealloc = result.negated ? 0 : 1;
389 		break;
390 	case Opt_noacsrules:
391 		opts->noacsrules = result.negated ? 1 : 0;
392 		break;
393 	case Opt_nocase:
394 		opts->nocase = result.negated ? 1 : 0;
395 		break;
396 	default:
397 		/* Should not be here unless we forget add case. */
398 		return -EINVAL;
399 	}
400 	return 0;
401 }
402 
403 static int ntfs_fs_reconfigure(struct fs_context *fc)
404 {
405 	struct super_block *sb = fc->root->d_sb;
406 	struct ntfs_sb_info *sbi = sb->s_fs_info;
407 	struct ntfs_mount_options *new_opts = fc->fs_private;
408 	int ro_rw;
409 
410 	ro_rw = sb_rdonly(sb) && !(fc->sb_flags & SB_RDONLY);
411 	if (ro_rw && (sbi->flags & NTFS_FLAGS_NEED_REPLAY)) {
412 		errorf(fc, "ntfs3: Couldn't remount rw because journal is not replayed. Please umount/remount instead\n");
413 		return -EINVAL;
414 	}
415 
416 	new_opts->nls = ntfs_load_nls(new_opts->nls_name);
417 	if (IS_ERR(new_opts->nls)) {
418 		new_opts->nls = NULL;
419 		errorf(fc, "ntfs3: Cannot load iocharset %s", new_opts->nls_name);
420 		return -EINVAL;
421 	}
422 	if (new_opts->nls != sbi->options->nls)
423 		return invalf(fc, "ntfs3: Cannot use different iocharset when remounting!");
424 
425 	sync_filesystem(sb);
426 
427 	if (ro_rw && (sbi->volume.flags & VOLUME_FLAG_DIRTY) &&
428 	    !new_opts->force) {
429 		errorf(fc, "ntfs3: Volume is dirty and \"force\" flag is not set!");
430 		return -EINVAL;
431 	}
432 
433 	swap(sbi->options, fc->fs_private);
434 
435 	return 0;
436 }
437 
438 static struct kmem_cache *ntfs_inode_cachep;
439 
440 static struct inode *ntfs_alloc_inode(struct super_block *sb)
441 {
442 	struct ntfs_inode *ni = alloc_inode_sb(sb, ntfs_inode_cachep, GFP_NOFS);
443 
444 	if (!ni)
445 		return NULL;
446 
447 	memset(ni, 0, offsetof(struct ntfs_inode, vfs_inode));
448 	mutex_init(&ni->ni_lock);
449 	return &ni->vfs_inode;
450 }
451 
452 static void ntfs_free_inode(struct inode *inode)
453 {
454 	struct ntfs_inode *ni = ntfs_i(inode);
455 
456 	mutex_destroy(&ni->ni_lock);
457 	kmem_cache_free(ntfs_inode_cachep, ni);
458 }
459 
460 static void init_once(void *foo)
461 {
462 	struct ntfs_inode *ni = foo;
463 
464 	inode_init_once(&ni->vfs_inode);
465 }
466 
467 /*
468  * put_ntfs - Noinline to reduce binary size.
469  */
470 static noinline void put_ntfs(struct ntfs_sb_info *sbi)
471 {
472 	kfree(sbi->new_rec);
473 	kvfree(ntfs_put_shared(sbi->upcase));
474 	kfree(sbi->def_table);
475 
476 	wnd_close(&sbi->mft.bitmap);
477 	wnd_close(&sbi->used.bitmap);
478 
479 	if (sbi->mft.ni)
480 		iput(&sbi->mft.ni->vfs_inode);
481 
482 	if (sbi->security.ni)
483 		iput(&sbi->security.ni->vfs_inode);
484 
485 	if (sbi->reparse.ni)
486 		iput(&sbi->reparse.ni->vfs_inode);
487 
488 	if (sbi->objid.ni)
489 		iput(&sbi->objid.ni->vfs_inode);
490 
491 	if (sbi->volume.ni)
492 		iput(&sbi->volume.ni->vfs_inode);
493 
494 	ntfs_update_mftmirr(sbi, 0);
495 
496 	indx_clear(&sbi->security.index_sii);
497 	indx_clear(&sbi->security.index_sdh);
498 	indx_clear(&sbi->reparse.index_r);
499 	indx_clear(&sbi->objid.index_o);
500 	kfree(sbi->compress.lznt);
501 #ifdef CONFIG_NTFS3_LZX_XPRESS
502 	xpress_free_decompressor(sbi->compress.xpress);
503 	lzx_free_decompressor(sbi->compress.lzx);
504 #endif
505 	kfree(sbi);
506 }
507 
508 static void ntfs_put_super(struct super_block *sb)
509 {
510 	struct ntfs_sb_info *sbi = sb->s_fs_info;
511 
512 	/* Mark rw ntfs as clear, if possible. */
513 	ntfs_set_state(sbi, NTFS_DIRTY_CLEAR);
514 
515 	put_mount_options(sbi->options);
516 	put_ntfs(sbi);
517 	sb->s_fs_info = NULL;
518 
519 	sync_blockdev(sb->s_bdev);
520 }
521 
522 static int ntfs_statfs(struct dentry *dentry, struct kstatfs *buf)
523 {
524 	struct super_block *sb = dentry->d_sb;
525 	struct ntfs_sb_info *sbi = sb->s_fs_info;
526 	struct wnd_bitmap *wnd = &sbi->used.bitmap;
527 
528 	buf->f_type = sb->s_magic;
529 	buf->f_bsize = sbi->cluster_size;
530 	buf->f_blocks = wnd->nbits;
531 
532 	buf->f_bfree = buf->f_bavail = wnd_zeroes(wnd);
533 	buf->f_fsid.val[0] = sbi->volume.ser_num;
534 	buf->f_fsid.val[1] = (sbi->volume.ser_num >> 32);
535 	buf->f_namelen = NTFS_NAME_LEN;
536 
537 	return 0;
538 }
539 
540 static int ntfs_show_options(struct seq_file *m, struct dentry *root)
541 {
542 	struct super_block *sb = root->d_sb;
543 	struct ntfs_sb_info *sbi = sb->s_fs_info;
544 	struct ntfs_mount_options *opts = sbi->options;
545 	struct user_namespace *user_ns = seq_user_ns(m);
546 
547 	seq_printf(m, ",uid=%u",
548 		  from_kuid_munged(user_ns, opts->fs_uid));
549 	seq_printf(m, ",gid=%u",
550 		  from_kgid_munged(user_ns, opts->fs_gid));
551 	if (opts->fmask)
552 		seq_printf(m, ",fmask=%04o", opts->fs_fmask_inv ^ 0xffff);
553 	if (opts->dmask)
554 		seq_printf(m, ",dmask=%04o", opts->fs_dmask_inv ^ 0xffff);
555 	if (opts->nls)
556 		seq_printf(m, ",iocharset=%s", opts->nls->charset);
557 	else
558 		seq_puts(m, ",iocharset=utf8");
559 	if (opts->sys_immutable)
560 		seq_puts(m, ",sys_immutable");
561 	if (opts->discard)
562 		seq_puts(m, ",discard");
563 	if (opts->sparse)
564 		seq_puts(m, ",sparse");
565 	if (opts->showmeta)
566 		seq_puts(m, ",showmeta");
567 	if (opts->nohidden)
568 		seq_puts(m, ",nohidden");
569 	if (opts->windows_names)
570 		seq_puts(m, ",windows_names");
571 	if (opts->hide_dot_files)
572 		seq_puts(m, ",hide_dot_files");
573 	if (opts->force)
574 		seq_puts(m, ",force");
575 	if (opts->noacsrules)
576 		seq_puts(m, ",noacsrules");
577 	if (opts->prealloc)
578 		seq_puts(m, ",prealloc");
579 	if (sb->s_flags & SB_POSIXACL)
580 		seq_puts(m, ",acl");
581 
582 	return 0;
583 }
584 
585 /*
586  * ntfs_sync_fs - super_operations::sync_fs
587  */
588 static int ntfs_sync_fs(struct super_block *sb, int wait)
589 {
590 	int err = 0, err2;
591 	struct ntfs_sb_info *sbi = sb->s_fs_info;
592 	struct ntfs_inode *ni;
593 	struct inode *inode;
594 
595 	ni = sbi->security.ni;
596 	if (ni) {
597 		inode = &ni->vfs_inode;
598 		err2 = _ni_write_inode(inode, wait);
599 		if (err2 && !err)
600 			err = err2;
601 	}
602 
603 	ni = sbi->objid.ni;
604 	if (ni) {
605 		inode = &ni->vfs_inode;
606 		err2 = _ni_write_inode(inode, wait);
607 		if (err2 && !err)
608 			err = err2;
609 	}
610 
611 	ni = sbi->reparse.ni;
612 	if (ni) {
613 		inode = &ni->vfs_inode;
614 		err2 = _ni_write_inode(inode, wait);
615 		if (err2 && !err)
616 			err = err2;
617 	}
618 
619 	if (!err)
620 		ntfs_set_state(sbi, NTFS_DIRTY_CLEAR);
621 
622 	ntfs_update_mftmirr(sbi, wait);
623 
624 	return err;
625 }
626 
627 static const struct super_operations ntfs_sops = {
628 	.alloc_inode = ntfs_alloc_inode,
629 	.free_inode = ntfs_free_inode,
630 	.evict_inode = ntfs_evict_inode,
631 	.put_super = ntfs_put_super,
632 	.statfs = ntfs_statfs,
633 	.show_options = ntfs_show_options,
634 	.sync_fs = ntfs_sync_fs,
635 	.write_inode = ntfs3_write_inode,
636 };
637 
638 static struct inode *ntfs_export_get_inode(struct super_block *sb, u64 ino,
639 					   u32 generation)
640 {
641 	struct MFT_REF ref;
642 	struct inode *inode;
643 
644 	ref.low = cpu_to_le32(ino);
645 #ifdef CONFIG_NTFS3_64BIT_CLUSTER
646 	ref.high = cpu_to_le16(ino >> 32);
647 #else
648 	ref.high = 0;
649 #endif
650 	ref.seq = cpu_to_le16(generation);
651 
652 	inode = ntfs_iget5(sb, &ref, NULL);
653 	if (!IS_ERR(inode) && is_bad_inode(inode)) {
654 		iput(inode);
655 		inode = ERR_PTR(-ESTALE);
656 	}
657 
658 	return inode;
659 }
660 
661 static struct dentry *ntfs_fh_to_dentry(struct super_block *sb, struct fid *fid,
662 					int fh_len, int fh_type)
663 {
664 	return generic_fh_to_dentry(sb, fid, fh_len, fh_type,
665 				    ntfs_export_get_inode);
666 }
667 
668 static struct dentry *ntfs_fh_to_parent(struct super_block *sb, struct fid *fid,
669 					int fh_len, int fh_type)
670 {
671 	return generic_fh_to_parent(sb, fid, fh_len, fh_type,
672 				    ntfs_export_get_inode);
673 }
674 
675 /* TODO: == ntfs_sync_inode */
676 static int ntfs_nfs_commit_metadata(struct inode *inode)
677 {
678 	return _ni_write_inode(inode, 1);
679 }
680 
681 static const struct export_operations ntfs_export_ops = {
682 	.fh_to_dentry = ntfs_fh_to_dentry,
683 	.fh_to_parent = ntfs_fh_to_parent,
684 	.get_parent = ntfs3_get_parent,
685 	.commit_metadata = ntfs_nfs_commit_metadata,
686 };
687 
688 /*
689  * format_size_gb - Return Gb,Mb to print with "%u.%02u Gb".
690  */
691 static u32 format_size_gb(const u64 bytes, u32 *mb)
692 {
693 	/* Do simple right 30 bit shift of 64 bit value. */
694 	u64 kbytes = bytes >> 10;
695 	u32 kbytes32 = kbytes;
696 
697 	*mb = (100 * (kbytes32 & 0xfffff) + 0x7ffff) >> 20;
698 	if (*mb >= 100)
699 		*mb = 99;
700 
701 	return (kbytes32 >> 20) | (((u32)(kbytes >> 32)) << 12);
702 }
703 
704 static u32 true_sectors_per_clst(const struct NTFS_BOOT *boot)
705 {
706 	if (boot->sectors_per_clusters <= 0x80)
707 		return boot->sectors_per_clusters;
708 	if (boot->sectors_per_clusters >= 0xf4) /* limit shift to 2MB max */
709 		return 1U << -(s8)boot->sectors_per_clusters;
710 	return -EINVAL;
711 }
712 
713 /*
714  * ntfs_init_from_boot - Init internal info from on-disk boot sector.
715  */
716 static int ntfs_init_from_boot(struct super_block *sb, u32 sector_size,
717 			       u64 dev_size)
718 {
719 	struct ntfs_sb_info *sbi = sb->s_fs_info;
720 	int err;
721 	u32 mb, gb, boot_sector_size, sct_per_clst, record_size;
722 	u64 sectors, clusters, mlcn, mlcn2;
723 	struct NTFS_BOOT *boot;
724 	struct buffer_head *bh;
725 	struct MFT_REC *rec;
726 	u16 fn, ao;
727 
728 	sbi->volume.blocks = dev_size >> PAGE_SHIFT;
729 
730 	bh = ntfs_bread(sb, 0);
731 	if (!bh)
732 		return -EIO;
733 
734 	err = -EINVAL;
735 	boot = (struct NTFS_BOOT *)bh->b_data;
736 
737 	if (memcmp(boot->system_id, "NTFS    ", sizeof("NTFS    ") - 1))
738 		goto out;
739 
740 	/* 0x55AA is not mandaroty. Thanks Maxim Suhanov*/
741 	/*if (0x55 != boot->boot_magic[0] || 0xAA != boot->boot_magic[1])
742 	 *	goto out;
743 	 */
744 
745 	boot_sector_size = (u32)boot->bytes_per_sector[1] << 8;
746 	if (boot->bytes_per_sector[0] || boot_sector_size < SECTOR_SIZE ||
747 	    !is_power_of_2(boot_sector_size)) {
748 		goto out;
749 	}
750 
751 	/* cluster size: 512, 1K, 2K, 4K, ... 2M */
752 	sct_per_clst = true_sectors_per_clst(boot);
753 	if ((int)sct_per_clst < 0)
754 		goto out;
755 	if (!is_power_of_2(sct_per_clst))
756 		goto out;
757 
758 	mlcn = le64_to_cpu(boot->mft_clst);
759 	mlcn2 = le64_to_cpu(boot->mft2_clst);
760 	sectors = le64_to_cpu(boot->sectors_per_volume);
761 
762 	if (mlcn * sct_per_clst >= sectors)
763 		goto out;
764 
765 	if (mlcn2 * sct_per_clst >= sectors)
766 		goto out;
767 
768 	/* Check MFT record size. */
769 	if ((boot->record_size < 0 &&
770 	     SECTOR_SIZE > (2U << (-boot->record_size))) ||
771 	    (boot->record_size >= 0 && !is_power_of_2(boot->record_size))) {
772 		goto out;
773 	}
774 
775 	/* Check index record size. */
776 	if ((boot->index_size < 0 &&
777 	     SECTOR_SIZE > (2U << (-boot->index_size))) ||
778 	    (boot->index_size >= 0 && !is_power_of_2(boot->index_size))) {
779 		goto out;
780 	}
781 
782 	sbi->volume.size = sectors * boot_sector_size;
783 
784 	gb = format_size_gb(sbi->volume.size + boot_sector_size, &mb);
785 
786 	/*
787 	 * - Volume formatted and mounted with the same sector size.
788 	 * - Volume formatted 4K and mounted as 512.
789 	 * - Volume formatted 512 and mounted as 4K.
790 	 */
791 	if (boot_sector_size != sector_size) {
792 		ntfs_warn(
793 			sb,
794 			"Different NTFS' sector size (%u) and media sector size (%u)",
795 			boot_sector_size, sector_size);
796 		dev_size += sector_size - 1;
797 	}
798 
799 	sbi->cluster_size = boot_sector_size * sct_per_clst;
800 	sbi->cluster_bits = blksize_bits(sbi->cluster_size);
801 
802 	sbi->mft.lbo = mlcn << sbi->cluster_bits;
803 	sbi->mft.lbo2 = mlcn2 << sbi->cluster_bits;
804 
805 	/* Compare boot's cluster and sector. */
806 	if (sbi->cluster_size < boot_sector_size)
807 		goto out;
808 
809 	/* Compare boot's cluster and media sector. */
810 	if (sbi->cluster_size < sector_size) {
811 		/* No way to use ntfs_get_block in this case. */
812 		ntfs_err(
813 			sb,
814 			"Failed to mount 'cause NTFS's cluster size (%u) is less than media sector size (%u)",
815 			sbi->cluster_size, sector_size);
816 		goto out;
817 	}
818 
819 	sbi->cluster_mask = sbi->cluster_size - 1;
820 	sbi->cluster_mask_inv = ~(u64)sbi->cluster_mask;
821 	sbi->record_size = record_size = boot->record_size < 0
822 						 ? 1 << (-boot->record_size)
823 						 : (u32)boot->record_size
824 							   << sbi->cluster_bits;
825 
826 	if (record_size > MAXIMUM_BYTES_PER_MFT || record_size < SECTOR_SIZE)
827 		goto out;
828 
829 	sbi->record_bits = blksize_bits(record_size);
830 	sbi->attr_size_tr = (5 * record_size >> 4); // ~320 bytes
831 
832 	sbi->max_bytes_per_attr =
833 		record_size - ALIGN(MFTRECORD_FIXUP_OFFSET_1, 8) -
834 		ALIGN(((record_size >> SECTOR_SHIFT) * sizeof(short)), 8) -
835 		ALIGN(sizeof(enum ATTR_TYPE), 8);
836 
837 	sbi->index_size = boot->index_size < 0
838 				  ? 1u << (-boot->index_size)
839 				  : (u32)boot->index_size << sbi->cluster_bits;
840 
841 	sbi->volume.ser_num = le64_to_cpu(boot->serial_num);
842 
843 	/* Warning if RAW volume. */
844 	if (dev_size < sbi->volume.size + boot_sector_size) {
845 		u32 mb0, gb0;
846 
847 		gb0 = format_size_gb(dev_size, &mb0);
848 		ntfs_warn(
849 			sb,
850 			"RAW NTFS volume: Filesystem size %u.%02u Gb > volume size %u.%02u Gb. Mount in read-only",
851 			gb, mb, gb0, mb0);
852 		sb->s_flags |= SB_RDONLY;
853 	}
854 
855 	clusters = sbi->volume.size >> sbi->cluster_bits;
856 #ifndef CONFIG_NTFS3_64BIT_CLUSTER
857 	/* 32 bits per cluster. */
858 	if (clusters >> 32) {
859 		ntfs_notice(
860 			sb,
861 			"NTFS %u.%02u Gb is too big to use 32 bits per cluster",
862 			gb, mb);
863 		goto out;
864 	}
865 #elif BITS_PER_LONG < 64
866 #error "CONFIG_NTFS3_64BIT_CLUSTER incompatible in 32 bit OS"
867 #endif
868 
869 	sbi->used.bitmap.nbits = clusters;
870 
871 	rec = kzalloc(record_size, GFP_NOFS);
872 	if (!rec) {
873 		err = -ENOMEM;
874 		goto out;
875 	}
876 
877 	sbi->new_rec = rec;
878 	rec->rhdr.sign = NTFS_FILE_SIGNATURE;
879 	rec->rhdr.fix_off = cpu_to_le16(MFTRECORD_FIXUP_OFFSET_1);
880 	fn = (sbi->record_size >> SECTOR_SHIFT) + 1;
881 	rec->rhdr.fix_num = cpu_to_le16(fn);
882 	ao = ALIGN(MFTRECORD_FIXUP_OFFSET_1 + sizeof(short) * fn, 8);
883 	rec->attr_off = cpu_to_le16(ao);
884 	rec->used = cpu_to_le32(ao + ALIGN(sizeof(enum ATTR_TYPE), 8));
885 	rec->total = cpu_to_le32(sbi->record_size);
886 	((struct ATTRIB *)Add2Ptr(rec, ao))->type = ATTR_END;
887 
888 	sb_set_blocksize(sb, min_t(u32, sbi->cluster_size, PAGE_SIZE));
889 
890 	sbi->block_mask = sb->s_blocksize - 1;
891 	sbi->blocks_per_cluster = sbi->cluster_size >> sb->s_blocksize_bits;
892 	sbi->volume.blocks = sbi->volume.size >> sb->s_blocksize_bits;
893 
894 	/* Maximum size for normal files. */
895 	sbi->maxbytes = (clusters << sbi->cluster_bits) - 1;
896 
897 #ifdef CONFIG_NTFS3_64BIT_CLUSTER
898 	if (clusters >= (1ull << (64 - sbi->cluster_bits)))
899 		sbi->maxbytes = -1;
900 	sbi->maxbytes_sparse = -1;
901 	sb->s_maxbytes = MAX_LFS_FILESIZE;
902 #else
903 	/* Maximum size for sparse file. */
904 	sbi->maxbytes_sparse = (1ull << (sbi->cluster_bits + 32)) - 1;
905 	sb->s_maxbytes = 0xFFFFFFFFull << sbi->cluster_bits;
906 #endif
907 
908 	/*
909 	 * Compute the MFT zone at two steps.
910 	 * It would be nice if we are able to allocate 1/8 of
911 	 * total clusters for MFT but not more then 512 MB.
912 	 */
913 	sbi->zone_max = min_t(CLST, 0x20000000 >> sbi->cluster_bits, clusters >> 3);
914 
915 	err = 0;
916 
917 out:
918 	brelse(bh);
919 
920 	return err;
921 }
922 
923 /*
924  * ntfs_fill_super - Try to mount.
925  */
926 static int ntfs_fill_super(struct super_block *sb, struct fs_context *fc)
927 {
928 	int err;
929 	struct ntfs_sb_info *sbi = sb->s_fs_info;
930 	struct block_device *bdev = sb->s_bdev;
931 	struct inode *inode;
932 	struct ntfs_inode *ni;
933 	size_t i, tt, bad_len, bad_frags;
934 	CLST vcn, lcn, len;
935 	struct ATTRIB *attr;
936 	const struct VOLUME_INFO *info;
937 	u32 idx, done, bytes;
938 	struct ATTR_DEF_ENTRY *t;
939 	u16 *shared;
940 	struct MFT_REF ref;
941 
942 	ref.high = 0;
943 
944 	sbi->sb = sb;
945 	sbi->options = fc->fs_private;
946 	fc->fs_private = NULL;
947 	sb->s_flags |= SB_NODIRATIME;
948 	sb->s_magic = 0x7366746e; // "ntfs"
949 	sb->s_op = &ntfs_sops;
950 	sb->s_export_op = &ntfs_export_ops;
951 	sb->s_time_gran = NTFS_TIME_GRAN; // 100 nsec
952 	sb->s_xattr = ntfs_xattr_handlers;
953 	sb->s_d_op = sbi->options->nocase ? &ntfs_dentry_ops : NULL;
954 
955 	sbi->options->nls = ntfs_load_nls(sbi->options->nls_name);
956 	if (IS_ERR(sbi->options->nls)) {
957 		sbi->options->nls = NULL;
958 		errorf(fc, "Cannot load nls %s", sbi->options->nls_name);
959 		err = -EINVAL;
960 		goto out;
961 	}
962 
963 	if (bdev_max_discard_sectors(bdev) && bdev_discard_granularity(bdev)) {
964 		sbi->discard_granularity = bdev_discard_granularity(bdev);
965 		sbi->discard_granularity_mask_inv =
966 			~(u64)(sbi->discard_granularity - 1);
967 	}
968 
969 	/* Parse boot. */
970 	err = ntfs_init_from_boot(sb, bdev_logical_block_size(bdev),
971 				  bdev_nr_bytes(bdev));
972 	if (err)
973 		goto out;
974 
975 	/*
976 	 * Load $Volume. This should be done before $LogFile
977 	 * 'cause 'sbi->volume.ni' is used 'ntfs_set_state'.
978 	 */
979 	ref.low = cpu_to_le32(MFT_REC_VOL);
980 	ref.seq = cpu_to_le16(MFT_REC_VOL);
981 	inode = ntfs_iget5(sb, &ref, &NAME_VOLUME);
982 	if (IS_ERR(inode)) {
983 		ntfs_err(sb, "Failed to load $Volume.");
984 		err = PTR_ERR(inode);
985 		goto out;
986 	}
987 
988 	ni = ntfs_i(inode);
989 
990 	/* Load and save label (not necessary). */
991 	attr = ni_find_attr(ni, NULL, NULL, ATTR_LABEL, NULL, 0, NULL, NULL);
992 
993 	if (!attr) {
994 		/* It is ok if no ATTR_LABEL */
995 	} else if (!attr->non_res && !is_attr_ext(attr)) {
996 		/* $AttrDef allows labels to be up to 128 symbols. */
997 		err = utf16s_to_utf8s(resident_data(attr),
998 				      le32_to_cpu(attr->res.data_size) >> 1,
999 				      UTF16_LITTLE_ENDIAN, sbi->volume.label,
1000 				      sizeof(sbi->volume.label));
1001 		if (err < 0)
1002 			sbi->volume.label[0] = 0;
1003 	} else {
1004 		/* Should we break mounting here? */
1005 		//err = -EINVAL;
1006 		//goto put_inode_out;
1007 	}
1008 
1009 	attr = ni_find_attr(ni, attr, NULL, ATTR_VOL_INFO, NULL, 0, NULL, NULL);
1010 	if (!attr || is_attr_ext(attr)) {
1011 		err = -EINVAL;
1012 		goto put_inode_out;
1013 	}
1014 
1015 	info = resident_data_ex(attr, SIZEOF_ATTRIBUTE_VOLUME_INFO);
1016 	if (!info) {
1017 		err = -EINVAL;
1018 		goto put_inode_out;
1019 	}
1020 
1021 	sbi->volume.major_ver = info->major_ver;
1022 	sbi->volume.minor_ver = info->minor_ver;
1023 	sbi->volume.flags = info->flags;
1024 	sbi->volume.ni = ni;
1025 
1026 	/* Load $MFTMirr to estimate recs_mirr. */
1027 	ref.low = cpu_to_le32(MFT_REC_MIRR);
1028 	ref.seq = cpu_to_le16(MFT_REC_MIRR);
1029 	inode = ntfs_iget5(sb, &ref, &NAME_MIRROR);
1030 	if (IS_ERR(inode)) {
1031 		ntfs_err(sb, "Failed to load $MFTMirr.");
1032 		err = PTR_ERR(inode);
1033 		goto out;
1034 	}
1035 
1036 	sbi->mft.recs_mirr =
1037 		ntfs_up_cluster(sbi, inode->i_size) >> sbi->record_bits;
1038 
1039 	iput(inode);
1040 
1041 	/* Load LogFile to replay. */
1042 	ref.low = cpu_to_le32(MFT_REC_LOG);
1043 	ref.seq = cpu_to_le16(MFT_REC_LOG);
1044 	inode = ntfs_iget5(sb, &ref, &NAME_LOGFILE);
1045 	if (IS_ERR(inode)) {
1046 		ntfs_err(sb, "Failed to load \x24LogFile.");
1047 		err = PTR_ERR(inode);
1048 		goto out;
1049 	}
1050 
1051 	ni = ntfs_i(inode);
1052 
1053 	err = ntfs_loadlog_and_replay(ni, sbi);
1054 	if (err)
1055 		goto put_inode_out;
1056 
1057 	iput(inode);
1058 
1059 	if (sbi->flags & NTFS_FLAGS_NEED_REPLAY) {
1060 		if (!sb_rdonly(sb)) {
1061 			ntfs_warn(sb,
1062 				  "failed to replay log file. Can't mount rw!");
1063 			err = -EINVAL;
1064 			goto out;
1065 		}
1066 	} else if (sbi->volume.flags & VOLUME_FLAG_DIRTY) {
1067 		if (!sb_rdonly(sb) && !sbi->options->force) {
1068 			ntfs_warn(
1069 				sb,
1070 				"volume is dirty and \"force\" flag is not set!");
1071 			err = -EINVAL;
1072 			goto out;
1073 		}
1074 	}
1075 
1076 	/* Load $MFT. */
1077 	ref.low = cpu_to_le32(MFT_REC_MFT);
1078 	ref.seq = cpu_to_le16(1);
1079 
1080 	inode = ntfs_iget5(sb, &ref, &NAME_MFT);
1081 	if (IS_ERR(inode)) {
1082 		ntfs_err(sb, "Failed to load $MFT.");
1083 		err = PTR_ERR(inode);
1084 		goto out;
1085 	}
1086 
1087 	ni = ntfs_i(inode);
1088 
1089 	sbi->mft.used = ni->i_valid >> sbi->record_bits;
1090 	tt = inode->i_size >> sbi->record_bits;
1091 	sbi->mft.next_free = MFT_REC_USER;
1092 
1093 	err = wnd_init(&sbi->mft.bitmap, sb, tt);
1094 	if (err)
1095 		goto put_inode_out;
1096 
1097 	err = ni_load_all_mi(ni);
1098 	if (err)
1099 		goto put_inode_out;
1100 
1101 	sbi->mft.ni = ni;
1102 
1103 	/* Load $Bitmap. */
1104 	ref.low = cpu_to_le32(MFT_REC_BITMAP);
1105 	ref.seq = cpu_to_le16(MFT_REC_BITMAP);
1106 	inode = ntfs_iget5(sb, &ref, &NAME_BITMAP);
1107 	if (IS_ERR(inode)) {
1108 		ntfs_err(sb, "Failed to load $Bitmap.");
1109 		err = PTR_ERR(inode);
1110 		goto out;
1111 	}
1112 
1113 #ifndef CONFIG_NTFS3_64BIT_CLUSTER
1114 	if (inode->i_size >> 32) {
1115 		err = -EINVAL;
1116 		goto put_inode_out;
1117 	}
1118 #endif
1119 
1120 	/* Check bitmap boundary. */
1121 	tt = sbi->used.bitmap.nbits;
1122 	if (inode->i_size < bitmap_size(tt)) {
1123 		err = -EINVAL;
1124 		goto put_inode_out;
1125 	}
1126 
1127 	/* Not necessary. */
1128 	sbi->used.bitmap.set_tail = true;
1129 	err = wnd_init(&sbi->used.bitmap, sb, tt);
1130 	if (err)
1131 		goto put_inode_out;
1132 
1133 	iput(inode);
1134 
1135 	/* Compute the MFT zone. */
1136 	err = ntfs_refresh_zone(sbi);
1137 	if (err)
1138 		goto out;
1139 
1140 	/* Load $BadClus. */
1141 	ref.low = cpu_to_le32(MFT_REC_BADCLUST);
1142 	ref.seq = cpu_to_le16(MFT_REC_BADCLUST);
1143 	inode = ntfs_iget5(sb, &ref, &NAME_BADCLUS);
1144 	if (IS_ERR(inode)) {
1145 		err = PTR_ERR(inode);
1146 		ntfs_err(sb, "Failed to load $BadClus (%d).", err);
1147 		goto out;
1148 	}
1149 
1150 	ni = ntfs_i(inode);
1151 	bad_len = bad_frags = 0;
1152 	for (i = 0; run_get_entry(&ni->file.run, i, &vcn, &lcn, &len); i++) {
1153 		if (lcn == SPARSE_LCN)
1154 			continue;
1155 
1156 		bad_len += len;
1157 		bad_frags += 1;
1158 		if (sb_rdonly(sb))
1159 			continue;
1160 
1161 		if (wnd_set_used_safe(&sbi->used.bitmap, lcn, len, &tt) || tt) {
1162 			/* Bad blocks marked as free in bitmap. */
1163 			ntfs_set_state(sbi, NTFS_DIRTY_ERROR);
1164 		}
1165 	}
1166 	if (bad_len) {
1167 		/*
1168 		 * Notice about bad blocks.
1169 		 * In normal cases these blocks are marked as used in bitmap.
1170 		 * And we never allocate space in it.
1171 		 */
1172 		ntfs_notice(sb,
1173 			    "Volume contains %zu bad blocks in %zu fragments.",
1174 			    bad_len, bad_frags);
1175 	}
1176 	iput(inode);
1177 
1178 	/* Load $AttrDef. */
1179 	ref.low = cpu_to_le32(MFT_REC_ATTR);
1180 	ref.seq = cpu_to_le16(MFT_REC_ATTR);
1181 	inode = ntfs_iget5(sb, &ref, &NAME_ATTRDEF);
1182 	if (IS_ERR(inode)) {
1183 		ntfs_err(sb, "Failed to load $AttrDef -> %d", err);
1184 		err = PTR_ERR(inode);
1185 		goto out;
1186 	}
1187 
1188 	if (inode->i_size < sizeof(struct ATTR_DEF_ENTRY)) {
1189 		err = -EINVAL;
1190 		goto put_inode_out;
1191 	}
1192 	bytes = inode->i_size;
1193 	sbi->def_table = t = kmalloc(bytes, GFP_NOFS | __GFP_NOWARN);
1194 	if (!t) {
1195 		err = -ENOMEM;
1196 		goto put_inode_out;
1197 	}
1198 
1199 	for (done = idx = 0; done < bytes; done += PAGE_SIZE, idx++) {
1200 		unsigned long tail = bytes - done;
1201 		struct page *page = ntfs_map_page(inode->i_mapping, idx);
1202 
1203 		if (IS_ERR(page)) {
1204 			err = PTR_ERR(page);
1205 			goto put_inode_out;
1206 		}
1207 		memcpy(Add2Ptr(t, done), page_address(page),
1208 		       min(PAGE_SIZE, tail));
1209 		ntfs_unmap_page(page);
1210 
1211 		if (!idx && ATTR_STD != t->type) {
1212 			err = -EINVAL;
1213 			goto put_inode_out;
1214 		}
1215 	}
1216 
1217 	t += 1;
1218 	sbi->def_entries = 1;
1219 	done = sizeof(struct ATTR_DEF_ENTRY);
1220 	sbi->reparse.max_size = MAXIMUM_REPARSE_DATA_BUFFER_SIZE;
1221 	sbi->ea_max_size = 0x10000; /* default formatter value */
1222 
1223 	while (done + sizeof(struct ATTR_DEF_ENTRY) <= bytes) {
1224 		u32 t32 = le32_to_cpu(t->type);
1225 		u64 sz = le64_to_cpu(t->max_sz);
1226 
1227 		if ((t32 & 0xF) || le32_to_cpu(t[-1].type) >= t32)
1228 			break;
1229 
1230 		if (t->type == ATTR_REPARSE)
1231 			sbi->reparse.max_size = sz;
1232 		else if (t->type == ATTR_EA)
1233 			sbi->ea_max_size = sz;
1234 
1235 		done += sizeof(struct ATTR_DEF_ENTRY);
1236 		t += 1;
1237 		sbi->def_entries += 1;
1238 	}
1239 	iput(inode);
1240 
1241 	/* Load $UpCase. */
1242 	ref.low = cpu_to_le32(MFT_REC_UPCASE);
1243 	ref.seq = cpu_to_le16(MFT_REC_UPCASE);
1244 	inode = ntfs_iget5(sb, &ref, &NAME_UPCASE);
1245 	if (IS_ERR(inode)) {
1246 		ntfs_err(sb, "Failed to load $UpCase.");
1247 		err = PTR_ERR(inode);
1248 		goto out;
1249 	}
1250 
1251 	if (inode->i_size != 0x10000 * sizeof(short)) {
1252 		err = -EINVAL;
1253 		goto put_inode_out;
1254 	}
1255 
1256 	for (idx = 0; idx < (0x10000 * sizeof(short) >> PAGE_SHIFT); idx++) {
1257 		const __le16 *src;
1258 		u16 *dst = Add2Ptr(sbi->upcase, idx << PAGE_SHIFT);
1259 		struct page *page = ntfs_map_page(inode->i_mapping, idx);
1260 
1261 		if (IS_ERR(page)) {
1262 			err = PTR_ERR(page);
1263 			goto put_inode_out;
1264 		}
1265 
1266 		src = page_address(page);
1267 
1268 #ifdef __BIG_ENDIAN
1269 		for (i = 0; i < PAGE_SIZE / sizeof(u16); i++)
1270 			*dst++ = le16_to_cpu(*src++);
1271 #else
1272 		memcpy(dst, src, PAGE_SIZE);
1273 #endif
1274 		ntfs_unmap_page(page);
1275 	}
1276 
1277 	shared = ntfs_set_shared(sbi->upcase, 0x10000 * sizeof(short));
1278 	if (shared && sbi->upcase != shared) {
1279 		kvfree(sbi->upcase);
1280 		sbi->upcase = shared;
1281 	}
1282 
1283 	iput(inode);
1284 
1285 	if (is_ntfs3(sbi)) {
1286 		/* Load $Secure. */
1287 		err = ntfs_security_init(sbi);
1288 		if (err)
1289 			goto out;
1290 
1291 		/* Load $Extend. */
1292 		err = ntfs_extend_init(sbi);
1293 		if (err)
1294 			goto load_root;
1295 
1296 		/* Load $Extend\$Reparse. */
1297 		err = ntfs_reparse_init(sbi);
1298 		if (err)
1299 			goto load_root;
1300 
1301 		/* Load $Extend\$ObjId. */
1302 		err = ntfs_objid_init(sbi);
1303 		if (err)
1304 			goto load_root;
1305 	}
1306 
1307 load_root:
1308 	/* Load root. */
1309 	ref.low = cpu_to_le32(MFT_REC_ROOT);
1310 	ref.seq = cpu_to_le16(MFT_REC_ROOT);
1311 	inode = ntfs_iget5(sb, &ref, &NAME_ROOT);
1312 	if (IS_ERR(inode) || !inode->i_op) {
1313 		ntfs_err(sb, "Failed to load root.");
1314 		err = IS_ERR(inode) ? PTR_ERR(inode) : -EINVAL;
1315 		goto out;
1316 	}
1317 
1318 	sb->s_root = d_make_root(inode);
1319 	if (!sb->s_root) {
1320 		err = -ENOMEM;
1321 		goto put_inode_out;
1322 	}
1323 
1324 	return 0;
1325 
1326 put_inode_out:
1327 	iput(inode);
1328 out:
1329 	/*
1330 	 * Free resources here.
1331 	 * ntfs_fs_free will be called with fc->s_fs_info = NULL
1332 	 */
1333 	put_mount_options(sbi->options);
1334 	put_ntfs(sbi);
1335 	sb->s_fs_info = NULL;
1336 
1337 	return err;
1338 }
1339 
1340 void ntfs_unmap_meta(struct super_block *sb, CLST lcn, CLST len)
1341 {
1342 	struct ntfs_sb_info *sbi = sb->s_fs_info;
1343 	struct block_device *bdev = sb->s_bdev;
1344 	sector_t devblock = (u64)lcn * sbi->blocks_per_cluster;
1345 	unsigned long blocks = (u64)len * sbi->blocks_per_cluster;
1346 	unsigned long cnt = 0;
1347 	unsigned long limit = global_zone_page_state(NR_FREE_PAGES)
1348 			      << (PAGE_SHIFT - sb->s_blocksize_bits);
1349 
1350 	if (limit >= 0x2000)
1351 		limit -= 0x1000;
1352 	else if (limit < 32)
1353 		limit = 32;
1354 	else
1355 		limit >>= 1;
1356 
1357 	while (blocks--) {
1358 		clean_bdev_aliases(bdev, devblock++, 1);
1359 		if (cnt++ >= limit) {
1360 			sync_blockdev(bdev);
1361 			cnt = 0;
1362 		}
1363 	}
1364 }
1365 
1366 /*
1367  * ntfs_discard - Issue a discard request (trim for SSD).
1368  */
1369 int ntfs_discard(struct ntfs_sb_info *sbi, CLST lcn, CLST len)
1370 {
1371 	int err;
1372 	u64 lbo, bytes, start, end;
1373 	struct super_block *sb;
1374 
1375 	if (sbi->used.next_free_lcn == lcn + len)
1376 		sbi->used.next_free_lcn = lcn;
1377 
1378 	if (sbi->flags & NTFS_FLAGS_NODISCARD)
1379 		return -EOPNOTSUPP;
1380 
1381 	if (!sbi->options->discard)
1382 		return -EOPNOTSUPP;
1383 
1384 	lbo = (u64)lcn << sbi->cluster_bits;
1385 	bytes = (u64)len << sbi->cluster_bits;
1386 
1387 	/* Align up 'start' on discard_granularity. */
1388 	start = (lbo + sbi->discard_granularity - 1) &
1389 		sbi->discard_granularity_mask_inv;
1390 	/* Align down 'end' on discard_granularity. */
1391 	end = (lbo + bytes) & sbi->discard_granularity_mask_inv;
1392 
1393 	sb = sbi->sb;
1394 	if (start >= end)
1395 		return 0;
1396 
1397 	err = blkdev_issue_discard(sb->s_bdev, start >> 9, (end - start) >> 9,
1398 				   GFP_NOFS);
1399 
1400 	if (err == -EOPNOTSUPP)
1401 		sbi->flags |= NTFS_FLAGS_NODISCARD;
1402 
1403 	return err;
1404 }
1405 
1406 static int ntfs_fs_get_tree(struct fs_context *fc)
1407 {
1408 	return get_tree_bdev(fc, ntfs_fill_super);
1409 }
1410 
1411 /*
1412  * ntfs_fs_free - Free fs_context.
1413  *
1414  * Note that this will be called after fill_super and reconfigure
1415  * even when they pass. So they have to take pointers if they pass.
1416  */
1417 static void ntfs_fs_free(struct fs_context *fc)
1418 {
1419 	struct ntfs_mount_options *opts = fc->fs_private;
1420 	struct ntfs_sb_info *sbi = fc->s_fs_info;
1421 
1422 	if (sbi)
1423 		put_ntfs(sbi);
1424 
1425 	if (opts)
1426 		put_mount_options(opts);
1427 }
1428 
1429 static const struct fs_context_operations ntfs_context_ops = {
1430 	.parse_param	= ntfs_fs_parse_param,
1431 	.get_tree	= ntfs_fs_get_tree,
1432 	.reconfigure	= ntfs_fs_reconfigure,
1433 	.free		= ntfs_fs_free,
1434 };
1435 
1436 /*
1437  * ntfs_init_fs_context - Initialize spi and opts
1438  *
1439  * This will called when mount/remount. We will first initialize
1440  * options so that if remount we can use just that.
1441  */
1442 static int ntfs_init_fs_context(struct fs_context *fc)
1443 {
1444 	struct ntfs_mount_options *opts;
1445 	struct ntfs_sb_info *sbi;
1446 
1447 	opts = kzalloc(sizeof(struct ntfs_mount_options), GFP_NOFS);
1448 	if (!opts)
1449 		return -ENOMEM;
1450 
1451 	/* Default options. */
1452 	opts->fs_uid = current_uid();
1453 	opts->fs_gid = current_gid();
1454 	opts->fs_fmask_inv = ~current_umask();
1455 	opts->fs_dmask_inv = ~current_umask();
1456 
1457 	if (fc->purpose == FS_CONTEXT_FOR_RECONFIGURE)
1458 		goto ok;
1459 
1460 	sbi = kzalloc(sizeof(struct ntfs_sb_info), GFP_NOFS);
1461 	if (!sbi)
1462 		goto free_opts;
1463 
1464 	sbi->upcase = kvmalloc(0x10000 * sizeof(short), GFP_KERNEL);
1465 	if (!sbi->upcase)
1466 		goto free_sbi;
1467 
1468 	ratelimit_state_init(&sbi->msg_ratelimit, DEFAULT_RATELIMIT_INTERVAL,
1469 			     DEFAULT_RATELIMIT_BURST);
1470 
1471 	mutex_init(&sbi->compress.mtx_lznt);
1472 #ifdef CONFIG_NTFS3_LZX_XPRESS
1473 	mutex_init(&sbi->compress.mtx_xpress);
1474 	mutex_init(&sbi->compress.mtx_lzx);
1475 #endif
1476 
1477 	fc->s_fs_info = sbi;
1478 ok:
1479 	fc->fs_private = opts;
1480 	fc->ops = &ntfs_context_ops;
1481 
1482 	return 0;
1483 free_sbi:
1484 	kfree(sbi);
1485 free_opts:
1486 	kfree(opts);
1487 	return -ENOMEM;
1488 }
1489 
1490 // clang-format off
1491 static struct file_system_type ntfs_fs_type = {
1492 	.owner			= THIS_MODULE,
1493 	.name			= "ntfs3",
1494 	.init_fs_context	= ntfs_init_fs_context,
1495 	.parameters		= ntfs_fs_parameters,
1496 	.kill_sb		= kill_block_super,
1497 	.fs_flags		= FS_REQUIRES_DEV | FS_ALLOW_IDMAP,
1498 };
1499 // clang-format on
1500 
1501 static int __init init_ntfs_fs(void)
1502 {
1503 	int err;
1504 
1505 	pr_info("ntfs3: Max link count %u\n", NTFS_LINK_MAX);
1506 
1507 	if (IS_ENABLED(CONFIG_NTFS3_FS_POSIX_ACL))
1508 		pr_info("ntfs3: Enabled Linux POSIX ACLs support\n");
1509 	if (IS_ENABLED(CONFIG_NTFS3_64BIT_CLUSTER))
1510 		pr_notice("ntfs3: Warning: Activated 64 bits per cluster. Windows does not support this\n");
1511 	if (IS_ENABLED(CONFIG_NTFS3_LZX_XPRESS))
1512 		pr_info("ntfs3: Read-only LZX/Xpress compression included\n");
1513 
1514 	err = ntfs3_init_bitmap();
1515 	if (err)
1516 		return err;
1517 
1518 	ntfs_inode_cachep = kmem_cache_create(
1519 		"ntfs_inode_cache", sizeof(struct ntfs_inode), 0,
1520 		(SLAB_RECLAIM_ACCOUNT | SLAB_MEM_SPREAD | SLAB_ACCOUNT),
1521 		init_once);
1522 	if (!ntfs_inode_cachep) {
1523 		err = -ENOMEM;
1524 		goto out1;
1525 	}
1526 
1527 	err = register_filesystem(&ntfs_fs_type);
1528 	if (err)
1529 		goto out;
1530 
1531 	return 0;
1532 out:
1533 	kmem_cache_destroy(ntfs_inode_cachep);
1534 out1:
1535 	ntfs3_exit_bitmap();
1536 	return err;
1537 }
1538 
1539 static void __exit exit_ntfs_fs(void)
1540 {
1541 	rcu_barrier();
1542 	kmem_cache_destroy(ntfs_inode_cachep);
1543 	unregister_filesystem(&ntfs_fs_type);
1544 	ntfs3_exit_bitmap();
1545 }
1546 
1547 MODULE_LICENSE("GPL");
1548 MODULE_DESCRIPTION("ntfs3 read/write filesystem");
1549 #ifdef CONFIG_NTFS3_FS_POSIX_ACL
1550 MODULE_INFO(behaviour, "Enabled Linux POSIX ACLs support");
1551 #endif
1552 #ifdef CONFIG_NTFS3_64BIT_CLUSTER
1553 MODULE_INFO(cluster, "Warning: Activated 64 bits per cluster. Windows does not support this");
1554 #endif
1555 #ifdef CONFIG_NTFS3_LZX_XPRESS
1556 MODULE_INFO(compression, "Read-only lzx/xpress compression included");
1557 #endif
1558 
1559 MODULE_AUTHOR("Konstantin Komarov");
1560 MODULE_ALIAS_FS("ntfs3");
1561 
1562 module_init(init_ntfs_fs);
1563 module_exit(exit_ntfs_fs);
1564