xref: /openbmc/linux/fs/ntfs/super.c (revision 63dc02bd)
1 /*
2  * super.c - NTFS kernel super block handling. Part of the Linux-NTFS project.
3  *
4  * Copyright (c) 2001-2012 Anton Altaparmakov and Tuxera Inc.
5  * Copyright (c) 2001,2002 Richard Russon
6  *
7  * This program/include file is free software; you can redistribute it and/or
8  * modify it under the terms of the GNU General Public License as published
9  * by the Free Software Foundation; either version 2 of the License, or
10  * (at your option) any later version.
11  *
12  * This program/include file is distributed in the hope that it will be
13  * useful, but WITHOUT ANY WARRANTY; without even the implied warranty
14  * of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
15  * GNU General Public License for more details.
16  *
17  * You should have received a copy of the GNU General Public License
18  * along with this program (in the main directory of the Linux-NTFS
19  * distribution in the file COPYING); if not, write to the Free Software
20  * Foundation,Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
21  */
22 
23 #include <linux/stddef.h>
24 #include <linux/init.h>
25 #include <linux/slab.h>
26 #include <linux/string.h>
27 #include <linux/spinlock.h>
28 #include <linux/blkdev.h>	/* For bdev_logical_block_size(). */
29 #include <linux/backing-dev.h>
30 #include <linux/buffer_head.h>
31 #include <linux/vfs.h>
32 #include <linux/moduleparam.h>
33 #include <linux/bitmap.h>
34 
35 #include "sysctl.h"
36 #include "logfile.h"
37 #include "quota.h"
38 #include "usnjrnl.h"
39 #include "dir.h"
40 #include "debug.h"
41 #include "index.h"
42 #include "inode.h"
43 #include "aops.h"
44 #include "layout.h"
45 #include "malloc.h"
46 #include "ntfs.h"
47 
48 /* Number of mounted filesystems which have compression enabled. */
49 static unsigned long ntfs_nr_compression_users;
50 
51 /* A global default upcase table and a corresponding reference count. */
52 static ntfschar *default_upcase = NULL;
53 static unsigned long ntfs_nr_upcase_users = 0;
54 
55 /* Error constants/strings used in inode.c::ntfs_show_options(). */
56 typedef enum {
57 	/* One of these must be present, default is ON_ERRORS_CONTINUE. */
58 	ON_ERRORS_PANIC			= 0x01,
59 	ON_ERRORS_REMOUNT_RO		= 0x02,
60 	ON_ERRORS_CONTINUE		= 0x04,
61 	/* Optional, can be combined with any of the above. */
62 	ON_ERRORS_RECOVER		= 0x10,
63 } ON_ERRORS_ACTIONS;
64 
65 const option_t on_errors_arr[] = {
66 	{ ON_ERRORS_PANIC,	"panic" },
67 	{ ON_ERRORS_REMOUNT_RO,	"remount-ro", },
68 	{ ON_ERRORS_CONTINUE,	"continue", },
69 	{ ON_ERRORS_RECOVER,	"recover" },
70 	{ 0,			NULL }
71 };
72 
73 /**
74  * simple_getbool -
75  *
76  * Copied from old ntfs driver (which copied from vfat driver).
77  */
78 static int simple_getbool(char *s, bool *setval)
79 {
80 	if (s) {
81 		if (!strcmp(s, "1") || !strcmp(s, "yes") || !strcmp(s, "true"))
82 			*setval = true;
83 		else if (!strcmp(s, "0") || !strcmp(s, "no") ||
84 							!strcmp(s, "false"))
85 			*setval = false;
86 		else
87 			return 0;
88 	} else
89 		*setval = true;
90 	return 1;
91 }
92 
93 /**
94  * parse_options - parse the (re)mount options
95  * @vol:	ntfs volume
96  * @opt:	string containing the (re)mount options
97  *
98  * Parse the recognized options in @opt for the ntfs volume described by @vol.
99  */
100 static bool parse_options(ntfs_volume *vol, char *opt)
101 {
102 	char *p, *v, *ov;
103 	static char *utf8 = "utf8";
104 	int errors = 0, sloppy = 0;
105 	uid_t uid = (uid_t)-1;
106 	gid_t gid = (gid_t)-1;
107 	umode_t fmask = (umode_t)-1, dmask = (umode_t)-1;
108 	int mft_zone_multiplier = -1, on_errors = -1;
109 	int show_sys_files = -1, case_sensitive = -1, disable_sparse = -1;
110 	struct nls_table *nls_map = NULL, *old_nls;
111 
112 	/* I am lazy... (-8 */
113 #define NTFS_GETOPT_WITH_DEFAULT(option, variable, default_value)	\
114 	if (!strcmp(p, option)) {					\
115 		if (!v || !*v)						\
116 			variable = default_value;			\
117 		else {							\
118 			variable = simple_strtoul(ov = v, &v, 0);	\
119 			if (*v)						\
120 				goto needs_val;				\
121 		}							\
122 	}
123 #define NTFS_GETOPT(option, variable)					\
124 	if (!strcmp(p, option)) {					\
125 		if (!v || !*v)						\
126 			goto needs_arg;					\
127 		variable = simple_strtoul(ov = v, &v, 0);		\
128 		if (*v)							\
129 			goto needs_val;					\
130 	}
131 #define NTFS_GETOPT_OCTAL(option, variable)				\
132 	if (!strcmp(p, option)) {					\
133 		if (!v || !*v)						\
134 			goto needs_arg;					\
135 		variable = simple_strtoul(ov = v, &v, 8);		\
136 		if (*v)							\
137 			goto needs_val;					\
138 	}
139 #define NTFS_GETOPT_BOOL(option, variable)				\
140 	if (!strcmp(p, option)) {					\
141 		bool val;						\
142 		if (!simple_getbool(v, &val))				\
143 			goto needs_bool;				\
144 		variable = val;						\
145 	}
146 #define NTFS_GETOPT_OPTIONS_ARRAY(option, variable, opt_array)		\
147 	if (!strcmp(p, option)) {					\
148 		int _i;							\
149 		if (!v || !*v)						\
150 			goto needs_arg;					\
151 		ov = v;							\
152 		if (variable == -1)					\
153 			variable = 0;					\
154 		for (_i = 0; opt_array[_i].str && *opt_array[_i].str; _i++) \
155 			if (!strcmp(opt_array[_i].str, v)) {		\
156 				variable |= opt_array[_i].val;		\
157 				break;					\
158 			}						\
159 		if (!opt_array[_i].str || !*opt_array[_i].str)		\
160 			goto needs_val;					\
161 	}
162 	if (!opt || !*opt)
163 		goto no_mount_options;
164 	ntfs_debug("Entering with mount options string: %s", opt);
165 	while ((p = strsep(&opt, ","))) {
166 		if ((v = strchr(p, '=')))
167 			*v++ = 0;
168 		NTFS_GETOPT("uid", uid)
169 		else NTFS_GETOPT("gid", gid)
170 		else NTFS_GETOPT_OCTAL("umask", fmask = dmask)
171 		else NTFS_GETOPT_OCTAL("fmask", fmask)
172 		else NTFS_GETOPT_OCTAL("dmask", dmask)
173 		else NTFS_GETOPT("mft_zone_multiplier", mft_zone_multiplier)
174 		else NTFS_GETOPT_WITH_DEFAULT("sloppy", sloppy, true)
175 		else NTFS_GETOPT_BOOL("show_sys_files", show_sys_files)
176 		else NTFS_GETOPT_BOOL("case_sensitive", case_sensitive)
177 		else NTFS_GETOPT_BOOL("disable_sparse", disable_sparse)
178 		else NTFS_GETOPT_OPTIONS_ARRAY("errors", on_errors,
179 				on_errors_arr)
180 		else if (!strcmp(p, "posix") || !strcmp(p, "show_inodes"))
181 			ntfs_warning(vol->sb, "Ignoring obsolete option %s.",
182 					p);
183 		else if (!strcmp(p, "nls") || !strcmp(p, "iocharset")) {
184 			if (!strcmp(p, "iocharset"))
185 				ntfs_warning(vol->sb, "Option iocharset is "
186 						"deprecated. Please use "
187 						"option nls=<charsetname> in "
188 						"the future.");
189 			if (!v || !*v)
190 				goto needs_arg;
191 use_utf8:
192 			old_nls = nls_map;
193 			nls_map = load_nls(v);
194 			if (!nls_map) {
195 				if (!old_nls) {
196 					ntfs_error(vol->sb, "NLS character set "
197 							"%s not found.", v);
198 					return false;
199 				}
200 				ntfs_error(vol->sb, "NLS character set %s not "
201 						"found. Using previous one %s.",
202 						v, old_nls->charset);
203 				nls_map = old_nls;
204 			} else /* nls_map */ {
205 				unload_nls(old_nls);
206 			}
207 		} else if (!strcmp(p, "utf8")) {
208 			bool val = false;
209 			ntfs_warning(vol->sb, "Option utf8 is no longer "
210 				   "supported, using option nls=utf8. Please "
211 				   "use option nls=utf8 in the future and "
212 				   "make sure utf8 is compiled either as a "
213 				   "module or into the kernel.");
214 			if (!v || !*v)
215 				val = true;
216 			else if (!simple_getbool(v, &val))
217 				goto needs_bool;
218 			if (val) {
219 				v = utf8;
220 				goto use_utf8;
221 			}
222 		} else {
223 			ntfs_error(vol->sb, "Unrecognized mount option %s.", p);
224 			if (errors < INT_MAX)
225 				errors++;
226 		}
227 #undef NTFS_GETOPT_OPTIONS_ARRAY
228 #undef NTFS_GETOPT_BOOL
229 #undef NTFS_GETOPT
230 #undef NTFS_GETOPT_WITH_DEFAULT
231 	}
232 no_mount_options:
233 	if (errors && !sloppy)
234 		return false;
235 	if (sloppy)
236 		ntfs_warning(vol->sb, "Sloppy option given. Ignoring "
237 				"unrecognized mount option(s) and continuing.");
238 	/* Keep this first! */
239 	if (on_errors != -1) {
240 		if (!on_errors) {
241 			ntfs_error(vol->sb, "Invalid errors option argument "
242 					"or bug in options parser.");
243 			return false;
244 		}
245 	}
246 	if (nls_map) {
247 		if (vol->nls_map && vol->nls_map != nls_map) {
248 			ntfs_error(vol->sb, "Cannot change NLS character set "
249 					"on remount.");
250 			return false;
251 		} /* else (!vol->nls_map) */
252 		ntfs_debug("Using NLS character set %s.", nls_map->charset);
253 		vol->nls_map = nls_map;
254 	} else /* (!nls_map) */ {
255 		if (!vol->nls_map) {
256 			vol->nls_map = load_nls_default();
257 			if (!vol->nls_map) {
258 				ntfs_error(vol->sb, "Failed to load default "
259 						"NLS character set.");
260 				return false;
261 			}
262 			ntfs_debug("Using default NLS character set (%s).",
263 					vol->nls_map->charset);
264 		}
265 	}
266 	if (mft_zone_multiplier != -1) {
267 		if (vol->mft_zone_multiplier && vol->mft_zone_multiplier !=
268 				mft_zone_multiplier) {
269 			ntfs_error(vol->sb, "Cannot change mft_zone_multiplier "
270 					"on remount.");
271 			return false;
272 		}
273 		if (mft_zone_multiplier < 1 || mft_zone_multiplier > 4) {
274 			ntfs_error(vol->sb, "Invalid mft_zone_multiplier. "
275 					"Using default value, i.e. 1.");
276 			mft_zone_multiplier = 1;
277 		}
278 		vol->mft_zone_multiplier = mft_zone_multiplier;
279 	}
280 	if (!vol->mft_zone_multiplier)
281 		vol->mft_zone_multiplier = 1;
282 	if (on_errors != -1)
283 		vol->on_errors = on_errors;
284 	if (!vol->on_errors || vol->on_errors == ON_ERRORS_RECOVER)
285 		vol->on_errors |= ON_ERRORS_CONTINUE;
286 	if (uid != (uid_t)-1)
287 		vol->uid = uid;
288 	if (gid != (gid_t)-1)
289 		vol->gid = gid;
290 	if (fmask != (umode_t)-1)
291 		vol->fmask = fmask;
292 	if (dmask != (umode_t)-1)
293 		vol->dmask = dmask;
294 	if (show_sys_files != -1) {
295 		if (show_sys_files)
296 			NVolSetShowSystemFiles(vol);
297 		else
298 			NVolClearShowSystemFiles(vol);
299 	}
300 	if (case_sensitive != -1) {
301 		if (case_sensitive)
302 			NVolSetCaseSensitive(vol);
303 		else
304 			NVolClearCaseSensitive(vol);
305 	}
306 	if (disable_sparse != -1) {
307 		if (disable_sparse)
308 			NVolClearSparseEnabled(vol);
309 		else {
310 			if (!NVolSparseEnabled(vol) &&
311 					vol->major_ver && vol->major_ver < 3)
312 				ntfs_warning(vol->sb, "Not enabling sparse "
313 						"support due to NTFS volume "
314 						"version %i.%i (need at least "
315 						"version 3.0).", vol->major_ver,
316 						vol->minor_ver);
317 			else
318 				NVolSetSparseEnabled(vol);
319 		}
320 	}
321 	return true;
322 needs_arg:
323 	ntfs_error(vol->sb, "The %s option requires an argument.", p);
324 	return false;
325 needs_bool:
326 	ntfs_error(vol->sb, "The %s option requires a boolean argument.", p);
327 	return false;
328 needs_val:
329 	ntfs_error(vol->sb, "Invalid %s option argument: %s", p, ov);
330 	return false;
331 }
332 
333 #ifdef NTFS_RW
334 
335 /**
336  * ntfs_write_volume_flags - write new flags to the volume information flags
337  * @vol:	ntfs volume on which to modify the flags
338  * @flags:	new flags value for the volume information flags
339  *
340  * Internal function.  You probably want to use ntfs_{set,clear}_volume_flags()
341  * instead (see below).
342  *
343  * Replace the volume information flags on the volume @vol with the value
344  * supplied in @flags.  Note, this overwrites the volume information flags, so
345  * make sure to combine the flags you want to modify with the old flags and use
346  * the result when calling ntfs_write_volume_flags().
347  *
348  * Return 0 on success and -errno on error.
349  */
350 static int ntfs_write_volume_flags(ntfs_volume *vol, const VOLUME_FLAGS flags)
351 {
352 	ntfs_inode *ni = NTFS_I(vol->vol_ino);
353 	MFT_RECORD *m;
354 	VOLUME_INFORMATION *vi;
355 	ntfs_attr_search_ctx *ctx;
356 	int err;
357 
358 	ntfs_debug("Entering, old flags = 0x%x, new flags = 0x%x.",
359 			le16_to_cpu(vol->vol_flags), le16_to_cpu(flags));
360 	if (vol->vol_flags == flags)
361 		goto done;
362 	BUG_ON(!ni);
363 	m = map_mft_record(ni);
364 	if (IS_ERR(m)) {
365 		err = PTR_ERR(m);
366 		goto err_out;
367 	}
368 	ctx = ntfs_attr_get_search_ctx(ni, m);
369 	if (!ctx) {
370 		err = -ENOMEM;
371 		goto put_unm_err_out;
372 	}
373 	err = ntfs_attr_lookup(AT_VOLUME_INFORMATION, NULL, 0, 0, 0, NULL, 0,
374 			ctx);
375 	if (err)
376 		goto put_unm_err_out;
377 	vi = (VOLUME_INFORMATION*)((u8*)ctx->attr +
378 			le16_to_cpu(ctx->attr->data.resident.value_offset));
379 	vol->vol_flags = vi->flags = flags;
380 	flush_dcache_mft_record_page(ctx->ntfs_ino);
381 	mark_mft_record_dirty(ctx->ntfs_ino);
382 	ntfs_attr_put_search_ctx(ctx);
383 	unmap_mft_record(ni);
384 done:
385 	ntfs_debug("Done.");
386 	return 0;
387 put_unm_err_out:
388 	if (ctx)
389 		ntfs_attr_put_search_ctx(ctx);
390 	unmap_mft_record(ni);
391 err_out:
392 	ntfs_error(vol->sb, "Failed with error code %i.", -err);
393 	return err;
394 }
395 
396 /**
397  * ntfs_set_volume_flags - set bits in the volume information flags
398  * @vol:	ntfs volume on which to modify the flags
399  * @flags:	flags to set on the volume
400  *
401  * Set the bits in @flags in the volume information flags on the volume @vol.
402  *
403  * Return 0 on success and -errno on error.
404  */
405 static inline int ntfs_set_volume_flags(ntfs_volume *vol, VOLUME_FLAGS flags)
406 {
407 	flags &= VOLUME_FLAGS_MASK;
408 	return ntfs_write_volume_flags(vol, vol->vol_flags | flags);
409 }
410 
411 /**
412  * ntfs_clear_volume_flags - clear bits in the volume information flags
413  * @vol:	ntfs volume on which to modify the flags
414  * @flags:	flags to clear on the volume
415  *
416  * Clear the bits in @flags in the volume information flags on the volume @vol.
417  *
418  * Return 0 on success and -errno on error.
419  */
420 static inline int ntfs_clear_volume_flags(ntfs_volume *vol, VOLUME_FLAGS flags)
421 {
422 	flags &= VOLUME_FLAGS_MASK;
423 	flags = vol->vol_flags & cpu_to_le16(~le16_to_cpu(flags));
424 	return ntfs_write_volume_flags(vol, flags);
425 }
426 
427 #endif /* NTFS_RW */
428 
429 /**
430  * ntfs_remount - change the mount options of a mounted ntfs filesystem
431  * @sb:		superblock of mounted ntfs filesystem
432  * @flags:	remount flags
433  * @opt:	remount options string
434  *
435  * Change the mount options of an already mounted ntfs filesystem.
436  *
437  * NOTE:  The VFS sets the @sb->s_flags remount flags to @flags after
438  * ntfs_remount() returns successfully (i.e. returns 0).  Otherwise,
439  * @sb->s_flags are not changed.
440  */
441 static int ntfs_remount(struct super_block *sb, int *flags, char *opt)
442 {
443 	ntfs_volume *vol = NTFS_SB(sb);
444 
445 	ntfs_debug("Entering with remount options string: %s", opt);
446 
447 #ifndef NTFS_RW
448 	/* For read-only compiled driver, enforce read-only flag. */
449 	*flags |= MS_RDONLY;
450 #else /* NTFS_RW */
451 	/*
452 	 * For the read-write compiled driver, if we are remounting read-write,
453 	 * make sure there are no volume errors and that no unsupported volume
454 	 * flags are set.  Also, empty the logfile journal as it would become
455 	 * stale as soon as something is written to the volume and mark the
456 	 * volume dirty so that chkdsk is run if the volume is not umounted
457 	 * cleanly.  Finally, mark the quotas out of date so Windows rescans
458 	 * the volume on boot and updates them.
459 	 *
460 	 * When remounting read-only, mark the volume clean if no volume errors
461 	 * have occurred.
462 	 */
463 	if ((sb->s_flags & MS_RDONLY) && !(*flags & MS_RDONLY)) {
464 		static const char *es = ".  Cannot remount read-write.";
465 
466 		/* Remounting read-write. */
467 		if (NVolErrors(vol)) {
468 			ntfs_error(sb, "Volume has errors and is read-only%s",
469 					es);
470 			return -EROFS;
471 		}
472 		if (vol->vol_flags & VOLUME_IS_DIRTY) {
473 			ntfs_error(sb, "Volume is dirty and read-only%s", es);
474 			return -EROFS;
475 		}
476 		if (vol->vol_flags & VOLUME_MODIFIED_BY_CHKDSK) {
477 			ntfs_error(sb, "Volume has been modified by chkdsk "
478 					"and is read-only%s", es);
479 			return -EROFS;
480 		}
481 		if (vol->vol_flags & VOLUME_MUST_MOUNT_RO_MASK) {
482 			ntfs_error(sb, "Volume has unsupported flags set "
483 					"(0x%x) and is read-only%s",
484 					(unsigned)le16_to_cpu(vol->vol_flags),
485 					es);
486 			return -EROFS;
487 		}
488 		if (ntfs_set_volume_flags(vol, VOLUME_IS_DIRTY)) {
489 			ntfs_error(sb, "Failed to set dirty bit in volume "
490 					"information flags%s", es);
491 			return -EROFS;
492 		}
493 #if 0
494 		// TODO: Enable this code once we start modifying anything that
495 		//	 is different between NTFS 1.2 and 3.x...
496 		/* Set NT4 compatibility flag on newer NTFS version volumes. */
497 		if ((vol->major_ver > 1)) {
498 			if (ntfs_set_volume_flags(vol, VOLUME_MOUNTED_ON_NT4)) {
499 				ntfs_error(sb, "Failed to set NT4 "
500 						"compatibility flag%s", es);
501 				NVolSetErrors(vol);
502 				return -EROFS;
503 			}
504 		}
505 #endif
506 		if (!ntfs_empty_logfile(vol->logfile_ino)) {
507 			ntfs_error(sb, "Failed to empty journal $LogFile%s",
508 					es);
509 			NVolSetErrors(vol);
510 			return -EROFS;
511 		}
512 		if (!ntfs_mark_quotas_out_of_date(vol)) {
513 			ntfs_error(sb, "Failed to mark quotas out of date%s",
514 					es);
515 			NVolSetErrors(vol);
516 			return -EROFS;
517 		}
518 		if (!ntfs_stamp_usnjrnl(vol)) {
519 			ntfs_error(sb, "Failed to stamp transation log "
520 					"($UsnJrnl)%s", es);
521 			NVolSetErrors(vol);
522 			return -EROFS;
523 		}
524 	} else if (!(sb->s_flags & MS_RDONLY) && (*flags & MS_RDONLY)) {
525 		/* Remounting read-only. */
526 		if (!NVolErrors(vol)) {
527 			if (ntfs_clear_volume_flags(vol, VOLUME_IS_DIRTY))
528 				ntfs_warning(sb, "Failed to clear dirty bit "
529 						"in volume information "
530 						"flags.  Run chkdsk.");
531 		}
532 	}
533 #endif /* NTFS_RW */
534 
535 	// TODO: Deal with *flags.
536 
537 	if (!parse_options(vol, opt))
538 		return -EINVAL;
539 
540 	ntfs_debug("Done.");
541 	return 0;
542 }
543 
544 /**
545  * is_boot_sector_ntfs - check whether a boot sector is a valid NTFS boot sector
546  * @sb:		Super block of the device to which @b belongs.
547  * @b:		Boot sector of device @sb to check.
548  * @silent:	If 'true', all output will be silenced.
549  *
550  * is_boot_sector_ntfs() checks whether the boot sector @b is a valid NTFS boot
551  * sector. Returns 'true' if it is valid and 'false' if not.
552  *
553  * @sb is only needed for warning/error output, i.e. it can be NULL when silent
554  * is 'true'.
555  */
556 static bool is_boot_sector_ntfs(const struct super_block *sb,
557 		const NTFS_BOOT_SECTOR *b, const bool silent)
558 {
559 	/*
560 	 * Check that checksum == sum of u32 values from b to the checksum
561 	 * field.  If checksum is zero, no checking is done.  We will work when
562 	 * the checksum test fails, since some utilities update the boot sector
563 	 * ignoring the checksum which leaves the checksum out-of-date.  We
564 	 * report a warning if this is the case.
565 	 */
566 	if ((void*)b < (void*)&b->checksum && b->checksum && !silent) {
567 		le32 *u;
568 		u32 i;
569 
570 		for (i = 0, u = (le32*)b; u < (le32*)(&b->checksum); ++u)
571 			i += le32_to_cpup(u);
572 		if (le32_to_cpu(b->checksum) != i)
573 			ntfs_warning(sb, "Invalid boot sector checksum.");
574 	}
575 	/* Check OEMidentifier is "NTFS    " */
576 	if (b->oem_id != magicNTFS)
577 		goto not_ntfs;
578 	/* Check bytes per sector value is between 256 and 4096. */
579 	if (le16_to_cpu(b->bpb.bytes_per_sector) < 0x100 ||
580 			le16_to_cpu(b->bpb.bytes_per_sector) > 0x1000)
581 		goto not_ntfs;
582 	/* Check sectors per cluster value is valid. */
583 	switch (b->bpb.sectors_per_cluster) {
584 	case 1: case 2: case 4: case 8: case 16: case 32: case 64: case 128:
585 		break;
586 	default:
587 		goto not_ntfs;
588 	}
589 	/* Check the cluster size is not above the maximum (64kiB). */
590 	if ((u32)le16_to_cpu(b->bpb.bytes_per_sector) *
591 			b->bpb.sectors_per_cluster > NTFS_MAX_CLUSTER_SIZE)
592 		goto not_ntfs;
593 	/* Check reserved/unused fields are really zero. */
594 	if (le16_to_cpu(b->bpb.reserved_sectors) ||
595 			le16_to_cpu(b->bpb.root_entries) ||
596 			le16_to_cpu(b->bpb.sectors) ||
597 			le16_to_cpu(b->bpb.sectors_per_fat) ||
598 			le32_to_cpu(b->bpb.large_sectors) || b->bpb.fats)
599 		goto not_ntfs;
600 	/* Check clusters per file mft record value is valid. */
601 	if ((u8)b->clusters_per_mft_record < 0xe1 ||
602 			(u8)b->clusters_per_mft_record > 0xf7)
603 		switch (b->clusters_per_mft_record) {
604 		case 1: case 2: case 4: case 8: case 16: case 32: case 64:
605 			break;
606 		default:
607 			goto not_ntfs;
608 		}
609 	/* Check clusters per index block value is valid. */
610 	if ((u8)b->clusters_per_index_record < 0xe1 ||
611 			(u8)b->clusters_per_index_record > 0xf7)
612 		switch (b->clusters_per_index_record) {
613 		case 1: case 2: case 4: case 8: case 16: case 32: case 64:
614 			break;
615 		default:
616 			goto not_ntfs;
617 		}
618 	/*
619 	 * Check for valid end of sector marker. We will work without it, but
620 	 * many BIOSes will refuse to boot from a bootsector if the magic is
621 	 * incorrect, so we emit a warning.
622 	 */
623 	if (!silent && b->end_of_sector_marker != cpu_to_le16(0xaa55))
624 		ntfs_warning(sb, "Invalid end of sector marker.");
625 	return true;
626 not_ntfs:
627 	return false;
628 }
629 
630 /**
631  * read_ntfs_boot_sector - read the NTFS boot sector of a device
632  * @sb:		super block of device to read the boot sector from
633  * @silent:	if true, suppress all output
634  *
635  * Reads the boot sector from the device and validates it. If that fails, tries
636  * to read the backup boot sector, first from the end of the device a-la NT4 and
637  * later and then from the middle of the device a-la NT3.51 and before.
638  *
639  * If a valid boot sector is found but it is not the primary boot sector, we
640  * repair the primary boot sector silently (unless the device is read-only or
641  * the primary boot sector is not accessible).
642  *
643  * NOTE: To call this function, @sb must have the fields s_dev, the ntfs super
644  * block (u.ntfs_sb), nr_blocks and the device flags (s_flags) initialized
645  * to their respective values.
646  *
647  * Return the unlocked buffer head containing the boot sector or NULL on error.
648  */
649 static struct buffer_head *read_ntfs_boot_sector(struct super_block *sb,
650 		const int silent)
651 {
652 	const char *read_err_str = "Unable to read %s boot sector.";
653 	struct buffer_head *bh_primary, *bh_backup;
654 	sector_t nr_blocks = NTFS_SB(sb)->nr_blocks;
655 
656 	/* Try to read primary boot sector. */
657 	if ((bh_primary = sb_bread(sb, 0))) {
658 		if (is_boot_sector_ntfs(sb, (NTFS_BOOT_SECTOR*)
659 				bh_primary->b_data, silent))
660 			return bh_primary;
661 		if (!silent)
662 			ntfs_error(sb, "Primary boot sector is invalid.");
663 	} else if (!silent)
664 		ntfs_error(sb, read_err_str, "primary");
665 	if (!(NTFS_SB(sb)->on_errors & ON_ERRORS_RECOVER)) {
666 		if (bh_primary)
667 			brelse(bh_primary);
668 		if (!silent)
669 			ntfs_error(sb, "Mount option errors=recover not used. "
670 					"Aborting without trying to recover.");
671 		return NULL;
672 	}
673 	/* Try to read NT4+ backup boot sector. */
674 	if ((bh_backup = sb_bread(sb, nr_blocks - 1))) {
675 		if (is_boot_sector_ntfs(sb, (NTFS_BOOT_SECTOR*)
676 				bh_backup->b_data, silent))
677 			goto hotfix_primary_boot_sector;
678 		brelse(bh_backup);
679 	} else if (!silent)
680 		ntfs_error(sb, read_err_str, "backup");
681 	/* Try to read NT3.51- backup boot sector. */
682 	if ((bh_backup = sb_bread(sb, nr_blocks >> 1))) {
683 		if (is_boot_sector_ntfs(sb, (NTFS_BOOT_SECTOR*)
684 				bh_backup->b_data, silent))
685 			goto hotfix_primary_boot_sector;
686 		if (!silent)
687 			ntfs_error(sb, "Could not find a valid backup boot "
688 					"sector.");
689 		brelse(bh_backup);
690 	} else if (!silent)
691 		ntfs_error(sb, read_err_str, "backup");
692 	/* We failed. Cleanup and return. */
693 	if (bh_primary)
694 		brelse(bh_primary);
695 	return NULL;
696 hotfix_primary_boot_sector:
697 	if (bh_primary) {
698 		/*
699 		 * If we managed to read sector zero and the volume is not
700 		 * read-only, copy the found, valid backup boot sector to the
701 		 * primary boot sector.  Note we only copy the actual boot
702 		 * sector structure, not the actual whole device sector as that
703 		 * may be bigger and would potentially damage the $Boot system
704 		 * file (FIXME: Would be nice to know if the backup boot sector
705 		 * on a large sector device contains the whole boot loader or
706 		 * just the first 512 bytes).
707 		 */
708 		if (!(sb->s_flags & MS_RDONLY)) {
709 			ntfs_warning(sb, "Hot-fix: Recovering invalid primary "
710 					"boot sector from backup copy.");
711 			memcpy(bh_primary->b_data, bh_backup->b_data,
712 					NTFS_BLOCK_SIZE);
713 			mark_buffer_dirty(bh_primary);
714 			sync_dirty_buffer(bh_primary);
715 			if (buffer_uptodate(bh_primary)) {
716 				brelse(bh_backup);
717 				return bh_primary;
718 			}
719 			ntfs_error(sb, "Hot-fix: Device write error while "
720 					"recovering primary boot sector.");
721 		} else {
722 			ntfs_warning(sb, "Hot-fix: Recovery of primary boot "
723 					"sector failed: Read-only mount.");
724 		}
725 		brelse(bh_primary);
726 	}
727 	ntfs_warning(sb, "Using backup boot sector.");
728 	return bh_backup;
729 }
730 
731 /**
732  * parse_ntfs_boot_sector - parse the boot sector and store the data in @vol
733  * @vol:	volume structure to initialise with data from boot sector
734  * @b:		boot sector to parse
735  *
736  * Parse the ntfs boot sector @b and store all imporant information therein in
737  * the ntfs super block @vol.  Return 'true' on success and 'false' on error.
738  */
739 static bool parse_ntfs_boot_sector(ntfs_volume *vol, const NTFS_BOOT_SECTOR *b)
740 {
741 	unsigned int sectors_per_cluster_bits, nr_hidden_sects;
742 	int clusters_per_mft_record, clusters_per_index_record;
743 	s64 ll;
744 
745 	vol->sector_size = le16_to_cpu(b->bpb.bytes_per_sector);
746 	vol->sector_size_bits = ffs(vol->sector_size) - 1;
747 	ntfs_debug("vol->sector_size = %i (0x%x)", vol->sector_size,
748 			vol->sector_size);
749 	ntfs_debug("vol->sector_size_bits = %i (0x%x)", vol->sector_size_bits,
750 			vol->sector_size_bits);
751 	if (vol->sector_size < vol->sb->s_blocksize) {
752 		ntfs_error(vol->sb, "Sector size (%i) is smaller than the "
753 				"device block size (%lu).  This is not "
754 				"supported.  Sorry.", vol->sector_size,
755 				vol->sb->s_blocksize);
756 		return false;
757 	}
758 	ntfs_debug("sectors_per_cluster = 0x%x", b->bpb.sectors_per_cluster);
759 	sectors_per_cluster_bits = ffs(b->bpb.sectors_per_cluster) - 1;
760 	ntfs_debug("sectors_per_cluster_bits = 0x%x",
761 			sectors_per_cluster_bits);
762 	nr_hidden_sects = le32_to_cpu(b->bpb.hidden_sectors);
763 	ntfs_debug("number of hidden sectors = 0x%x", nr_hidden_sects);
764 	vol->cluster_size = vol->sector_size << sectors_per_cluster_bits;
765 	vol->cluster_size_mask = vol->cluster_size - 1;
766 	vol->cluster_size_bits = ffs(vol->cluster_size) - 1;
767 	ntfs_debug("vol->cluster_size = %i (0x%x)", vol->cluster_size,
768 			vol->cluster_size);
769 	ntfs_debug("vol->cluster_size_mask = 0x%x", vol->cluster_size_mask);
770 	ntfs_debug("vol->cluster_size_bits = %i", vol->cluster_size_bits);
771 	if (vol->cluster_size < vol->sector_size) {
772 		ntfs_error(vol->sb, "Cluster size (%i) is smaller than the "
773 				"sector size (%i).  This is not supported.  "
774 				"Sorry.", vol->cluster_size, vol->sector_size);
775 		return false;
776 	}
777 	clusters_per_mft_record = b->clusters_per_mft_record;
778 	ntfs_debug("clusters_per_mft_record = %i (0x%x)",
779 			clusters_per_mft_record, clusters_per_mft_record);
780 	if (clusters_per_mft_record > 0)
781 		vol->mft_record_size = vol->cluster_size <<
782 				(ffs(clusters_per_mft_record) - 1);
783 	else
784 		/*
785 		 * When mft_record_size < cluster_size, clusters_per_mft_record
786 		 * = -log2(mft_record_size) bytes. mft_record_size normaly is
787 		 * 1024 bytes, which is encoded as 0xF6 (-10 in decimal).
788 		 */
789 		vol->mft_record_size = 1 << -clusters_per_mft_record;
790 	vol->mft_record_size_mask = vol->mft_record_size - 1;
791 	vol->mft_record_size_bits = ffs(vol->mft_record_size) - 1;
792 	ntfs_debug("vol->mft_record_size = %i (0x%x)", vol->mft_record_size,
793 			vol->mft_record_size);
794 	ntfs_debug("vol->mft_record_size_mask = 0x%x",
795 			vol->mft_record_size_mask);
796 	ntfs_debug("vol->mft_record_size_bits = %i (0x%x)",
797 			vol->mft_record_size_bits, vol->mft_record_size_bits);
798 	/*
799 	 * We cannot support mft record sizes above the PAGE_CACHE_SIZE since
800 	 * we store $MFT/$DATA, the table of mft records in the page cache.
801 	 */
802 	if (vol->mft_record_size > PAGE_CACHE_SIZE) {
803 		ntfs_error(vol->sb, "Mft record size (%i) exceeds the "
804 				"PAGE_CACHE_SIZE on your system (%lu).  "
805 				"This is not supported.  Sorry.",
806 				vol->mft_record_size, PAGE_CACHE_SIZE);
807 		return false;
808 	}
809 	/* We cannot support mft record sizes below the sector size. */
810 	if (vol->mft_record_size < vol->sector_size) {
811 		ntfs_error(vol->sb, "Mft record size (%i) is smaller than the "
812 				"sector size (%i).  This is not supported.  "
813 				"Sorry.", vol->mft_record_size,
814 				vol->sector_size);
815 		return false;
816 	}
817 	clusters_per_index_record = b->clusters_per_index_record;
818 	ntfs_debug("clusters_per_index_record = %i (0x%x)",
819 			clusters_per_index_record, clusters_per_index_record);
820 	if (clusters_per_index_record > 0)
821 		vol->index_record_size = vol->cluster_size <<
822 				(ffs(clusters_per_index_record) - 1);
823 	else
824 		/*
825 		 * When index_record_size < cluster_size,
826 		 * clusters_per_index_record = -log2(index_record_size) bytes.
827 		 * index_record_size normaly equals 4096 bytes, which is
828 		 * encoded as 0xF4 (-12 in decimal).
829 		 */
830 		vol->index_record_size = 1 << -clusters_per_index_record;
831 	vol->index_record_size_mask = vol->index_record_size - 1;
832 	vol->index_record_size_bits = ffs(vol->index_record_size) - 1;
833 	ntfs_debug("vol->index_record_size = %i (0x%x)",
834 			vol->index_record_size, vol->index_record_size);
835 	ntfs_debug("vol->index_record_size_mask = 0x%x",
836 			vol->index_record_size_mask);
837 	ntfs_debug("vol->index_record_size_bits = %i (0x%x)",
838 			vol->index_record_size_bits,
839 			vol->index_record_size_bits);
840 	/* We cannot support index record sizes below the sector size. */
841 	if (vol->index_record_size < vol->sector_size) {
842 		ntfs_error(vol->sb, "Index record size (%i) is smaller than "
843 				"the sector size (%i).  This is not "
844 				"supported.  Sorry.", vol->index_record_size,
845 				vol->sector_size);
846 		return false;
847 	}
848 	/*
849 	 * Get the size of the volume in clusters and check for 64-bit-ness.
850 	 * Windows currently only uses 32 bits to save the clusters so we do
851 	 * the same as it is much faster on 32-bit CPUs.
852 	 */
853 	ll = sle64_to_cpu(b->number_of_sectors) >> sectors_per_cluster_bits;
854 	if ((u64)ll >= 1ULL << 32) {
855 		ntfs_error(vol->sb, "Cannot handle 64-bit clusters.  Sorry.");
856 		return false;
857 	}
858 	vol->nr_clusters = ll;
859 	ntfs_debug("vol->nr_clusters = 0x%llx", (long long)vol->nr_clusters);
860 	/*
861 	 * On an architecture where unsigned long is 32-bits, we restrict the
862 	 * volume size to 2TiB (2^41). On a 64-bit architecture, the compiler
863 	 * will hopefully optimize the whole check away.
864 	 */
865 	if (sizeof(unsigned long) < 8) {
866 		if ((ll << vol->cluster_size_bits) >= (1ULL << 41)) {
867 			ntfs_error(vol->sb, "Volume size (%lluTiB) is too "
868 					"large for this architecture.  "
869 					"Maximum supported is 2TiB.  Sorry.",
870 					(unsigned long long)ll >> (40 -
871 					vol->cluster_size_bits));
872 			return false;
873 		}
874 	}
875 	ll = sle64_to_cpu(b->mft_lcn);
876 	if (ll >= vol->nr_clusters) {
877 		ntfs_error(vol->sb, "MFT LCN (%lli, 0x%llx) is beyond end of "
878 				"volume.  Weird.", (unsigned long long)ll,
879 				(unsigned long long)ll);
880 		return false;
881 	}
882 	vol->mft_lcn = ll;
883 	ntfs_debug("vol->mft_lcn = 0x%llx", (long long)vol->mft_lcn);
884 	ll = sle64_to_cpu(b->mftmirr_lcn);
885 	if (ll >= vol->nr_clusters) {
886 		ntfs_error(vol->sb, "MFTMirr LCN (%lli, 0x%llx) is beyond end "
887 				"of volume.  Weird.", (unsigned long long)ll,
888 				(unsigned long long)ll);
889 		return false;
890 	}
891 	vol->mftmirr_lcn = ll;
892 	ntfs_debug("vol->mftmirr_lcn = 0x%llx", (long long)vol->mftmirr_lcn);
893 #ifdef NTFS_RW
894 	/*
895 	 * Work out the size of the mft mirror in number of mft records. If the
896 	 * cluster size is less than or equal to the size taken by four mft
897 	 * records, the mft mirror stores the first four mft records. If the
898 	 * cluster size is bigger than the size taken by four mft records, the
899 	 * mft mirror contains as many mft records as will fit into one
900 	 * cluster.
901 	 */
902 	if (vol->cluster_size <= (4 << vol->mft_record_size_bits))
903 		vol->mftmirr_size = 4;
904 	else
905 		vol->mftmirr_size = vol->cluster_size >>
906 				vol->mft_record_size_bits;
907 	ntfs_debug("vol->mftmirr_size = %i", vol->mftmirr_size);
908 #endif /* NTFS_RW */
909 	vol->serial_no = le64_to_cpu(b->volume_serial_number);
910 	ntfs_debug("vol->serial_no = 0x%llx",
911 			(unsigned long long)vol->serial_no);
912 	return true;
913 }
914 
915 /**
916  * ntfs_setup_allocators - initialize the cluster and mft allocators
917  * @vol:	volume structure for which to setup the allocators
918  *
919  * Setup the cluster (lcn) and mft allocators to the starting values.
920  */
921 static void ntfs_setup_allocators(ntfs_volume *vol)
922 {
923 #ifdef NTFS_RW
924 	LCN mft_zone_size, mft_lcn;
925 #endif /* NTFS_RW */
926 
927 	ntfs_debug("vol->mft_zone_multiplier = 0x%x",
928 			vol->mft_zone_multiplier);
929 #ifdef NTFS_RW
930 	/* Determine the size of the MFT zone. */
931 	mft_zone_size = vol->nr_clusters;
932 	switch (vol->mft_zone_multiplier) {  /* % of volume size in clusters */
933 	case 4:
934 		mft_zone_size >>= 1;			/* 50%   */
935 		break;
936 	case 3:
937 		mft_zone_size = (mft_zone_size +
938 				(mft_zone_size >> 1)) >> 2;	/* 37.5% */
939 		break;
940 	case 2:
941 		mft_zone_size >>= 2;			/* 25%   */
942 		break;
943 	/* case 1: */
944 	default:
945 		mft_zone_size >>= 3;			/* 12.5% */
946 		break;
947 	}
948 	/* Setup the mft zone. */
949 	vol->mft_zone_start = vol->mft_zone_pos = vol->mft_lcn;
950 	ntfs_debug("vol->mft_zone_pos = 0x%llx",
951 			(unsigned long long)vol->mft_zone_pos);
952 	/*
953 	 * Calculate the mft_lcn for an unmodified NTFS volume (see mkntfs
954 	 * source) and if the actual mft_lcn is in the expected place or even
955 	 * further to the front of the volume, extend the mft_zone to cover the
956 	 * beginning of the volume as well.  This is in order to protect the
957 	 * area reserved for the mft bitmap as well within the mft_zone itself.
958 	 * On non-standard volumes we do not protect it as the overhead would
959 	 * be higher than the speed increase we would get by doing it.
960 	 */
961 	mft_lcn = (8192 + 2 * vol->cluster_size - 1) / vol->cluster_size;
962 	if (mft_lcn * vol->cluster_size < 16 * 1024)
963 		mft_lcn = (16 * 1024 + vol->cluster_size - 1) /
964 				vol->cluster_size;
965 	if (vol->mft_zone_start <= mft_lcn)
966 		vol->mft_zone_start = 0;
967 	ntfs_debug("vol->mft_zone_start = 0x%llx",
968 			(unsigned long long)vol->mft_zone_start);
969 	/*
970 	 * Need to cap the mft zone on non-standard volumes so that it does
971 	 * not point outside the boundaries of the volume.  We do this by
972 	 * halving the zone size until we are inside the volume.
973 	 */
974 	vol->mft_zone_end = vol->mft_lcn + mft_zone_size;
975 	while (vol->mft_zone_end >= vol->nr_clusters) {
976 		mft_zone_size >>= 1;
977 		vol->mft_zone_end = vol->mft_lcn + mft_zone_size;
978 	}
979 	ntfs_debug("vol->mft_zone_end = 0x%llx",
980 			(unsigned long long)vol->mft_zone_end);
981 	/*
982 	 * Set the current position within each data zone to the start of the
983 	 * respective zone.
984 	 */
985 	vol->data1_zone_pos = vol->mft_zone_end;
986 	ntfs_debug("vol->data1_zone_pos = 0x%llx",
987 			(unsigned long long)vol->data1_zone_pos);
988 	vol->data2_zone_pos = 0;
989 	ntfs_debug("vol->data2_zone_pos = 0x%llx",
990 			(unsigned long long)vol->data2_zone_pos);
991 
992 	/* Set the mft data allocation position to mft record 24. */
993 	vol->mft_data_pos = 24;
994 	ntfs_debug("vol->mft_data_pos = 0x%llx",
995 			(unsigned long long)vol->mft_data_pos);
996 #endif /* NTFS_RW */
997 }
998 
999 #ifdef NTFS_RW
1000 
1001 /**
1002  * load_and_init_mft_mirror - load and setup the mft mirror inode for a volume
1003  * @vol:	ntfs super block describing device whose mft mirror to load
1004  *
1005  * Return 'true' on success or 'false' on error.
1006  */
1007 static bool load_and_init_mft_mirror(ntfs_volume *vol)
1008 {
1009 	struct inode *tmp_ino;
1010 	ntfs_inode *tmp_ni;
1011 
1012 	ntfs_debug("Entering.");
1013 	/* Get mft mirror inode. */
1014 	tmp_ino = ntfs_iget(vol->sb, FILE_MFTMirr);
1015 	if (IS_ERR(tmp_ino) || is_bad_inode(tmp_ino)) {
1016 		if (!IS_ERR(tmp_ino))
1017 			iput(tmp_ino);
1018 		/* Caller will display error message. */
1019 		return false;
1020 	}
1021 	/*
1022 	 * Re-initialize some specifics about $MFTMirr's inode as
1023 	 * ntfs_read_inode() will have set up the default ones.
1024 	 */
1025 	/* Set uid and gid to root. */
1026 	tmp_ino->i_uid = tmp_ino->i_gid = 0;
1027 	/* Regular file.  No access for anyone. */
1028 	tmp_ino->i_mode = S_IFREG;
1029 	/* No VFS initiated operations allowed for $MFTMirr. */
1030 	tmp_ino->i_op = &ntfs_empty_inode_ops;
1031 	tmp_ino->i_fop = &ntfs_empty_file_ops;
1032 	/* Put in our special address space operations. */
1033 	tmp_ino->i_mapping->a_ops = &ntfs_mst_aops;
1034 	tmp_ni = NTFS_I(tmp_ino);
1035 	/* The $MFTMirr, like the $MFT is multi sector transfer protected. */
1036 	NInoSetMstProtected(tmp_ni);
1037 	NInoSetSparseDisabled(tmp_ni);
1038 	/*
1039 	 * Set up our little cheat allowing us to reuse the async read io
1040 	 * completion handler for directories.
1041 	 */
1042 	tmp_ni->itype.index.block_size = vol->mft_record_size;
1043 	tmp_ni->itype.index.block_size_bits = vol->mft_record_size_bits;
1044 	vol->mftmirr_ino = tmp_ino;
1045 	ntfs_debug("Done.");
1046 	return true;
1047 }
1048 
1049 /**
1050  * check_mft_mirror - compare contents of the mft mirror with the mft
1051  * @vol:	ntfs super block describing device whose mft mirror to check
1052  *
1053  * Return 'true' on success or 'false' on error.
1054  *
1055  * Note, this function also results in the mft mirror runlist being completely
1056  * mapped into memory.  The mft mirror write code requires this and will BUG()
1057  * should it find an unmapped runlist element.
1058  */
1059 static bool check_mft_mirror(ntfs_volume *vol)
1060 {
1061 	struct super_block *sb = vol->sb;
1062 	ntfs_inode *mirr_ni;
1063 	struct page *mft_page, *mirr_page;
1064 	u8 *kmft, *kmirr;
1065 	runlist_element *rl, rl2[2];
1066 	pgoff_t index;
1067 	int mrecs_per_page, i;
1068 
1069 	ntfs_debug("Entering.");
1070 	/* Compare contents of $MFT and $MFTMirr. */
1071 	mrecs_per_page = PAGE_CACHE_SIZE / vol->mft_record_size;
1072 	BUG_ON(!mrecs_per_page);
1073 	BUG_ON(!vol->mftmirr_size);
1074 	mft_page = mirr_page = NULL;
1075 	kmft = kmirr = NULL;
1076 	index = i = 0;
1077 	do {
1078 		u32 bytes;
1079 
1080 		/* Switch pages if necessary. */
1081 		if (!(i % mrecs_per_page)) {
1082 			if (index) {
1083 				ntfs_unmap_page(mft_page);
1084 				ntfs_unmap_page(mirr_page);
1085 			}
1086 			/* Get the $MFT page. */
1087 			mft_page = ntfs_map_page(vol->mft_ino->i_mapping,
1088 					index);
1089 			if (IS_ERR(mft_page)) {
1090 				ntfs_error(sb, "Failed to read $MFT.");
1091 				return false;
1092 			}
1093 			kmft = page_address(mft_page);
1094 			/* Get the $MFTMirr page. */
1095 			mirr_page = ntfs_map_page(vol->mftmirr_ino->i_mapping,
1096 					index);
1097 			if (IS_ERR(mirr_page)) {
1098 				ntfs_error(sb, "Failed to read $MFTMirr.");
1099 				goto mft_unmap_out;
1100 			}
1101 			kmirr = page_address(mirr_page);
1102 			++index;
1103 		}
1104 		/* Do not check the record if it is not in use. */
1105 		if (((MFT_RECORD*)kmft)->flags & MFT_RECORD_IN_USE) {
1106 			/* Make sure the record is ok. */
1107 			if (ntfs_is_baad_recordp((le32*)kmft)) {
1108 				ntfs_error(sb, "Incomplete multi sector "
1109 						"transfer detected in mft "
1110 						"record %i.", i);
1111 mm_unmap_out:
1112 				ntfs_unmap_page(mirr_page);
1113 mft_unmap_out:
1114 				ntfs_unmap_page(mft_page);
1115 				return false;
1116 			}
1117 		}
1118 		/* Do not check the mirror record if it is not in use. */
1119 		if (((MFT_RECORD*)kmirr)->flags & MFT_RECORD_IN_USE) {
1120 			if (ntfs_is_baad_recordp((le32*)kmirr)) {
1121 				ntfs_error(sb, "Incomplete multi sector "
1122 						"transfer detected in mft "
1123 						"mirror record %i.", i);
1124 				goto mm_unmap_out;
1125 			}
1126 		}
1127 		/* Get the amount of data in the current record. */
1128 		bytes = le32_to_cpu(((MFT_RECORD*)kmft)->bytes_in_use);
1129 		if (bytes < sizeof(MFT_RECORD_OLD) ||
1130 				bytes > vol->mft_record_size ||
1131 				ntfs_is_baad_recordp((le32*)kmft)) {
1132 			bytes = le32_to_cpu(((MFT_RECORD*)kmirr)->bytes_in_use);
1133 			if (bytes < sizeof(MFT_RECORD_OLD) ||
1134 					bytes > vol->mft_record_size ||
1135 					ntfs_is_baad_recordp((le32*)kmirr))
1136 				bytes = vol->mft_record_size;
1137 		}
1138 		/* Compare the two records. */
1139 		if (memcmp(kmft, kmirr, bytes)) {
1140 			ntfs_error(sb, "$MFT and $MFTMirr (record %i) do not "
1141 					"match.  Run ntfsfix or chkdsk.", i);
1142 			goto mm_unmap_out;
1143 		}
1144 		kmft += vol->mft_record_size;
1145 		kmirr += vol->mft_record_size;
1146 	} while (++i < vol->mftmirr_size);
1147 	/* Release the last pages. */
1148 	ntfs_unmap_page(mft_page);
1149 	ntfs_unmap_page(mirr_page);
1150 
1151 	/* Construct the mft mirror runlist by hand. */
1152 	rl2[0].vcn = 0;
1153 	rl2[0].lcn = vol->mftmirr_lcn;
1154 	rl2[0].length = (vol->mftmirr_size * vol->mft_record_size +
1155 			vol->cluster_size - 1) / vol->cluster_size;
1156 	rl2[1].vcn = rl2[0].length;
1157 	rl2[1].lcn = LCN_ENOENT;
1158 	rl2[1].length = 0;
1159 	/*
1160 	 * Because we have just read all of the mft mirror, we know we have
1161 	 * mapped the full runlist for it.
1162 	 */
1163 	mirr_ni = NTFS_I(vol->mftmirr_ino);
1164 	down_read(&mirr_ni->runlist.lock);
1165 	rl = mirr_ni->runlist.rl;
1166 	/* Compare the two runlists.  They must be identical. */
1167 	i = 0;
1168 	do {
1169 		if (rl2[i].vcn != rl[i].vcn || rl2[i].lcn != rl[i].lcn ||
1170 				rl2[i].length != rl[i].length) {
1171 			ntfs_error(sb, "$MFTMirr location mismatch.  "
1172 					"Run chkdsk.");
1173 			up_read(&mirr_ni->runlist.lock);
1174 			return false;
1175 		}
1176 	} while (rl2[i++].length);
1177 	up_read(&mirr_ni->runlist.lock);
1178 	ntfs_debug("Done.");
1179 	return true;
1180 }
1181 
1182 /**
1183  * load_and_check_logfile - load and check the logfile inode for a volume
1184  * @vol:	ntfs super block describing device whose logfile to load
1185  *
1186  * Return 'true' on success or 'false' on error.
1187  */
1188 static bool load_and_check_logfile(ntfs_volume *vol,
1189 		RESTART_PAGE_HEADER **rp)
1190 {
1191 	struct inode *tmp_ino;
1192 
1193 	ntfs_debug("Entering.");
1194 	tmp_ino = ntfs_iget(vol->sb, FILE_LogFile);
1195 	if (IS_ERR(tmp_ino) || is_bad_inode(tmp_ino)) {
1196 		if (!IS_ERR(tmp_ino))
1197 			iput(tmp_ino);
1198 		/* Caller will display error message. */
1199 		return false;
1200 	}
1201 	if (!ntfs_check_logfile(tmp_ino, rp)) {
1202 		iput(tmp_ino);
1203 		/* ntfs_check_logfile() will have displayed error output. */
1204 		return false;
1205 	}
1206 	NInoSetSparseDisabled(NTFS_I(tmp_ino));
1207 	vol->logfile_ino = tmp_ino;
1208 	ntfs_debug("Done.");
1209 	return true;
1210 }
1211 
1212 #define NTFS_HIBERFIL_HEADER_SIZE	4096
1213 
1214 /**
1215  * check_windows_hibernation_status - check if Windows is suspended on a volume
1216  * @vol:	ntfs super block of device to check
1217  *
1218  * Check if Windows is hibernated on the ntfs volume @vol.  This is done by
1219  * looking for the file hiberfil.sys in the root directory of the volume.  If
1220  * the file is not present Windows is definitely not suspended.
1221  *
1222  * If hiberfil.sys exists and is less than 4kiB in size it means Windows is
1223  * definitely suspended (this volume is not the system volume).  Caveat:  on a
1224  * system with many volumes it is possible that the < 4kiB check is bogus but
1225  * for now this should do fine.
1226  *
1227  * If hiberfil.sys exists and is larger than 4kiB in size, we need to read the
1228  * hiberfil header (which is the first 4kiB).  If this begins with "hibr",
1229  * Windows is definitely suspended.  If it is completely full of zeroes,
1230  * Windows is definitely not hibernated.  Any other case is treated as if
1231  * Windows is suspended.  This caters for the above mentioned caveat of a
1232  * system with many volumes where no "hibr" magic would be present and there is
1233  * no zero header.
1234  *
1235  * Return 0 if Windows is not hibernated on the volume, >0 if Windows is
1236  * hibernated on the volume, and -errno on error.
1237  */
1238 static int check_windows_hibernation_status(ntfs_volume *vol)
1239 {
1240 	MFT_REF mref;
1241 	struct inode *vi;
1242 	struct page *page;
1243 	u32 *kaddr, *kend;
1244 	ntfs_name *name = NULL;
1245 	int ret = 1;
1246 	static const ntfschar hiberfil[13] = { cpu_to_le16('h'),
1247 			cpu_to_le16('i'), cpu_to_le16('b'),
1248 			cpu_to_le16('e'), cpu_to_le16('r'),
1249 			cpu_to_le16('f'), cpu_to_le16('i'),
1250 			cpu_to_le16('l'), cpu_to_le16('.'),
1251 			cpu_to_le16('s'), cpu_to_le16('y'),
1252 			cpu_to_le16('s'), 0 };
1253 
1254 	ntfs_debug("Entering.");
1255 	/*
1256 	 * Find the inode number for the hibernation file by looking up the
1257 	 * filename hiberfil.sys in the root directory.
1258 	 */
1259 	mutex_lock(&vol->root_ino->i_mutex);
1260 	mref = ntfs_lookup_inode_by_name(NTFS_I(vol->root_ino), hiberfil, 12,
1261 			&name);
1262 	mutex_unlock(&vol->root_ino->i_mutex);
1263 	if (IS_ERR_MREF(mref)) {
1264 		ret = MREF_ERR(mref);
1265 		/* If the file does not exist, Windows is not hibernated. */
1266 		if (ret == -ENOENT) {
1267 			ntfs_debug("hiberfil.sys not present.  Windows is not "
1268 					"hibernated on the volume.");
1269 			return 0;
1270 		}
1271 		/* A real error occurred. */
1272 		ntfs_error(vol->sb, "Failed to find inode number for "
1273 				"hiberfil.sys.");
1274 		return ret;
1275 	}
1276 	/* We do not care for the type of match that was found. */
1277 	kfree(name);
1278 	/* Get the inode. */
1279 	vi = ntfs_iget(vol->sb, MREF(mref));
1280 	if (IS_ERR(vi) || is_bad_inode(vi)) {
1281 		if (!IS_ERR(vi))
1282 			iput(vi);
1283 		ntfs_error(vol->sb, "Failed to load hiberfil.sys.");
1284 		return IS_ERR(vi) ? PTR_ERR(vi) : -EIO;
1285 	}
1286 	if (unlikely(i_size_read(vi) < NTFS_HIBERFIL_HEADER_SIZE)) {
1287 		ntfs_debug("hiberfil.sys is smaller than 4kiB (0x%llx).  "
1288 				"Windows is hibernated on the volume.  This "
1289 				"is not the system volume.", i_size_read(vi));
1290 		goto iput_out;
1291 	}
1292 	page = ntfs_map_page(vi->i_mapping, 0);
1293 	if (IS_ERR(page)) {
1294 		ntfs_error(vol->sb, "Failed to read from hiberfil.sys.");
1295 		ret = PTR_ERR(page);
1296 		goto iput_out;
1297 	}
1298 	kaddr = (u32*)page_address(page);
1299 	if (*(le32*)kaddr == cpu_to_le32(0x72626968)/*'hibr'*/) {
1300 		ntfs_debug("Magic \"hibr\" found in hiberfil.sys.  Windows is "
1301 				"hibernated on the volume.  This is the "
1302 				"system volume.");
1303 		goto unm_iput_out;
1304 	}
1305 	kend = kaddr + NTFS_HIBERFIL_HEADER_SIZE/sizeof(*kaddr);
1306 	do {
1307 		if (unlikely(*kaddr)) {
1308 			ntfs_debug("hiberfil.sys is larger than 4kiB "
1309 					"(0x%llx), does not contain the "
1310 					"\"hibr\" magic, and does not have a "
1311 					"zero header.  Windows is hibernated "
1312 					"on the volume.  This is not the "
1313 					"system volume.", i_size_read(vi));
1314 			goto unm_iput_out;
1315 		}
1316 	} while (++kaddr < kend);
1317 	ntfs_debug("hiberfil.sys contains a zero header.  Windows is not "
1318 			"hibernated on the volume.  This is the system "
1319 			"volume.");
1320 	ret = 0;
1321 unm_iput_out:
1322 	ntfs_unmap_page(page);
1323 iput_out:
1324 	iput(vi);
1325 	return ret;
1326 }
1327 
1328 /**
1329  * load_and_init_quota - load and setup the quota file for a volume if present
1330  * @vol:	ntfs super block describing device whose quota file to load
1331  *
1332  * Return 'true' on success or 'false' on error.  If $Quota is not present, we
1333  * leave vol->quota_ino as NULL and return success.
1334  */
1335 static bool load_and_init_quota(ntfs_volume *vol)
1336 {
1337 	MFT_REF mref;
1338 	struct inode *tmp_ino;
1339 	ntfs_name *name = NULL;
1340 	static const ntfschar Quota[7] = { cpu_to_le16('$'),
1341 			cpu_to_le16('Q'), cpu_to_le16('u'),
1342 			cpu_to_le16('o'), cpu_to_le16('t'),
1343 			cpu_to_le16('a'), 0 };
1344 	static ntfschar Q[3] = { cpu_to_le16('$'),
1345 			cpu_to_le16('Q'), 0 };
1346 
1347 	ntfs_debug("Entering.");
1348 	/*
1349 	 * Find the inode number for the quota file by looking up the filename
1350 	 * $Quota in the extended system files directory $Extend.
1351 	 */
1352 	mutex_lock(&vol->extend_ino->i_mutex);
1353 	mref = ntfs_lookup_inode_by_name(NTFS_I(vol->extend_ino), Quota, 6,
1354 			&name);
1355 	mutex_unlock(&vol->extend_ino->i_mutex);
1356 	if (IS_ERR_MREF(mref)) {
1357 		/*
1358 		 * If the file does not exist, quotas are disabled and have
1359 		 * never been enabled on this volume, just return success.
1360 		 */
1361 		if (MREF_ERR(mref) == -ENOENT) {
1362 			ntfs_debug("$Quota not present.  Volume does not have "
1363 					"quotas enabled.");
1364 			/*
1365 			 * No need to try to set quotas out of date if they are
1366 			 * not enabled.
1367 			 */
1368 			NVolSetQuotaOutOfDate(vol);
1369 			return true;
1370 		}
1371 		/* A real error occurred. */
1372 		ntfs_error(vol->sb, "Failed to find inode number for $Quota.");
1373 		return false;
1374 	}
1375 	/* We do not care for the type of match that was found. */
1376 	kfree(name);
1377 	/* Get the inode. */
1378 	tmp_ino = ntfs_iget(vol->sb, MREF(mref));
1379 	if (IS_ERR(tmp_ino) || is_bad_inode(tmp_ino)) {
1380 		if (!IS_ERR(tmp_ino))
1381 			iput(tmp_ino);
1382 		ntfs_error(vol->sb, "Failed to load $Quota.");
1383 		return false;
1384 	}
1385 	vol->quota_ino = tmp_ino;
1386 	/* Get the $Q index allocation attribute. */
1387 	tmp_ino = ntfs_index_iget(vol->quota_ino, Q, 2);
1388 	if (IS_ERR(tmp_ino)) {
1389 		ntfs_error(vol->sb, "Failed to load $Quota/$Q index.");
1390 		return false;
1391 	}
1392 	vol->quota_q_ino = tmp_ino;
1393 	ntfs_debug("Done.");
1394 	return true;
1395 }
1396 
1397 /**
1398  * load_and_init_usnjrnl - load and setup the transaction log if present
1399  * @vol:	ntfs super block describing device whose usnjrnl file to load
1400  *
1401  * Return 'true' on success or 'false' on error.
1402  *
1403  * If $UsnJrnl is not present or in the process of being disabled, we set
1404  * NVolUsnJrnlStamped() and return success.
1405  *
1406  * If the $UsnJrnl $DATA/$J attribute has a size equal to the lowest valid usn,
1407  * i.e. transaction logging has only just been enabled or the journal has been
1408  * stamped and nothing has been logged since, we also set NVolUsnJrnlStamped()
1409  * and return success.
1410  */
1411 static bool load_and_init_usnjrnl(ntfs_volume *vol)
1412 {
1413 	MFT_REF mref;
1414 	struct inode *tmp_ino;
1415 	ntfs_inode *tmp_ni;
1416 	struct page *page;
1417 	ntfs_name *name = NULL;
1418 	USN_HEADER *uh;
1419 	static const ntfschar UsnJrnl[9] = { cpu_to_le16('$'),
1420 			cpu_to_le16('U'), cpu_to_le16('s'),
1421 			cpu_to_le16('n'), cpu_to_le16('J'),
1422 			cpu_to_le16('r'), cpu_to_le16('n'),
1423 			cpu_to_le16('l'), 0 };
1424 	static ntfschar Max[5] = { cpu_to_le16('$'),
1425 			cpu_to_le16('M'), cpu_to_le16('a'),
1426 			cpu_to_le16('x'), 0 };
1427 	static ntfschar J[3] = { cpu_to_le16('$'),
1428 			cpu_to_le16('J'), 0 };
1429 
1430 	ntfs_debug("Entering.");
1431 	/*
1432 	 * Find the inode number for the transaction log file by looking up the
1433 	 * filename $UsnJrnl in the extended system files directory $Extend.
1434 	 */
1435 	mutex_lock(&vol->extend_ino->i_mutex);
1436 	mref = ntfs_lookup_inode_by_name(NTFS_I(vol->extend_ino), UsnJrnl, 8,
1437 			&name);
1438 	mutex_unlock(&vol->extend_ino->i_mutex);
1439 	if (IS_ERR_MREF(mref)) {
1440 		/*
1441 		 * If the file does not exist, transaction logging is disabled,
1442 		 * just return success.
1443 		 */
1444 		if (MREF_ERR(mref) == -ENOENT) {
1445 			ntfs_debug("$UsnJrnl not present.  Volume does not "
1446 					"have transaction logging enabled.");
1447 not_enabled:
1448 			/*
1449 			 * No need to try to stamp the transaction log if
1450 			 * transaction logging is not enabled.
1451 			 */
1452 			NVolSetUsnJrnlStamped(vol);
1453 			return true;
1454 		}
1455 		/* A real error occurred. */
1456 		ntfs_error(vol->sb, "Failed to find inode number for "
1457 				"$UsnJrnl.");
1458 		return false;
1459 	}
1460 	/* We do not care for the type of match that was found. */
1461 	kfree(name);
1462 	/* Get the inode. */
1463 	tmp_ino = ntfs_iget(vol->sb, MREF(mref));
1464 	if (unlikely(IS_ERR(tmp_ino) || is_bad_inode(tmp_ino))) {
1465 		if (!IS_ERR(tmp_ino))
1466 			iput(tmp_ino);
1467 		ntfs_error(vol->sb, "Failed to load $UsnJrnl.");
1468 		return false;
1469 	}
1470 	vol->usnjrnl_ino = tmp_ino;
1471 	/*
1472 	 * If the transaction log is in the process of being deleted, we can
1473 	 * ignore it.
1474 	 */
1475 	if (unlikely(vol->vol_flags & VOLUME_DELETE_USN_UNDERWAY)) {
1476 		ntfs_debug("$UsnJrnl in the process of being disabled.  "
1477 				"Volume does not have transaction logging "
1478 				"enabled.");
1479 		goto not_enabled;
1480 	}
1481 	/* Get the $DATA/$Max attribute. */
1482 	tmp_ino = ntfs_attr_iget(vol->usnjrnl_ino, AT_DATA, Max, 4);
1483 	if (IS_ERR(tmp_ino)) {
1484 		ntfs_error(vol->sb, "Failed to load $UsnJrnl/$DATA/$Max "
1485 				"attribute.");
1486 		return false;
1487 	}
1488 	vol->usnjrnl_max_ino = tmp_ino;
1489 	if (unlikely(i_size_read(tmp_ino) < sizeof(USN_HEADER))) {
1490 		ntfs_error(vol->sb, "Found corrupt $UsnJrnl/$DATA/$Max "
1491 				"attribute (size is 0x%llx but should be at "
1492 				"least 0x%zx bytes).", i_size_read(tmp_ino),
1493 				sizeof(USN_HEADER));
1494 		return false;
1495 	}
1496 	/* Get the $DATA/$J attribute. */
1497 	tmp_ino = ntfs_attr_iget(vol->usnjrnl_ino, AT_DATA, J, 2);
1498 	if (IS_ERR(tmp_ino)) {
1499 		ntfs_error(vol->sb, "Failed to load $UsnJrnl/$DATA/$J "
1500 				"attribute.");
1501 		return false;
1502 	}
1503 	vol->usnjrnl_j_ino = tmp_ino;
1504 	/* Verify $J is non-resident and sparse. */
1505 	tmp_ni = NTFS_I(vol->usnjrnl_j_ino);
1506 	if (unlikely(!NInoNonResident(tmp_ni) || !NInoSparse(tmp_ni))) {
1507 		ntfs_error(vol->sb, "$UsnJrnl/$DATA/$J attribute is resident "
1508 				"and/or not sparse.");
1509 		return false;
1510 	}
1511 	/* Read the USN_HEADER from $DATA/$Max. */
1512 	page = ntfs_map_page(vol->usnjrnl_max_ino->i_mapping, 0);
1513 	if (IS_ERR(page)) {
1514 		ntfs_error(vol->sb, "Failed to read from $UsnJrnl/$DATA/$Max "
1515 				"attribute.");
1516 		return false;
1517 	}
1518 	uh = (USN_HEADER*)page_address(page);
1519 	/* Sanity check the $Max. */
1520 	if (unlikely(sle64_to_cpu(uh->allocation_delta) >
1521 			sle64_to_cpu(uh->maximum_size))) {
1522 		ntfs_error(vol->sb, "Allocation delta (0x%llx) exceeds "
1523 				"maximum size (0x%llx).  $UsnJrnl is corrupt.",
1524 				(long long)sle64_to_cpu(uh->allocation_delta),
1525 				(long long)sle64_to_cpu(uh->maximum_size));
1526 		ntfs_unmap_page(page);
1527 		return false;
1528 	}
1529 	/*
1530 	 * If the transaction log has been stamped and nothing has been written
1531 	 * to it since, we do not need to stamp it.
1532 	 */
1533 	if (unlikely(sle64_to_cpu(uh->lowest_valid_usn) >=
1534 			i_size_read(vol->usnjrnl_j_ino))) {
1535 		if (likely(sle64_to_cpu(uh->lowest_valid_usn) ==
1536 				i_size_read(vol->usnjrnl_j_ino))) {
1537 			ntfs_unmap_page(page);
1538 			ntfs_debug("$UsnJrnl is enabled but nothing has been "
1539 					"logged since it was last stamped.  "
1540 					"Treating this as if the volume does "
1541 					"not have transaction logging "
1542 					"enabled.");
1543 			goto not_enabled;
1544 		}
1545 		ntfs_error(vol->sb, "$UsnJrnl has lowest valid usn (0x%llx) "
1546 				"which is out of bounds (0x%llx).  $UsnJrnl "
1547 				"is corrupt.",
1548 				(long long)sle64_to_cpu(uh->lowest_valid_usn),
1549 				i_size_read(vol->usnjrnl_j_ino));
1550 		ntfs_unmap_page(page);
1551 		return false;
1552 	}
1553 	ntfs_unmap_page(page);
1554 	ntfs_debug("Done.");
1555 	return true;
1556 }
1557 
1558 /**
1559  * load_and_init_attrdef - load the attribute definitions table for a volume
1560  * @vol:	ntfs super block describing device whose attrdef to load
1561  *
1562  * Return 'true' on success or 'false' on error.
1563  */
1564 static bool load_and_init_attrdef(ntfs_volume *vol)
1565 {
1566 	loff_t i_size;
1567 	struct super_block *sb = vol->sb;
1568 	struct inode *ino;
1569 	struct page *page;
1570 	pgoff_t index, max_index;
1571 	unsigned int size;
1572 
1573 	ntfs_debug("Entering.");
1574 	/* Read attrdef table and setup vol->attrdef and vol->attrdef_size. */
1575 	ino = ntfs_iget(sb, FILE_AttrDef);
1576 	if (IS_ERR(ino) || is_bad_inode(ino)) {
1577 		if (!IS_ERR(ino))
1578 			iput(ino);
1579 		goto failed;
1580 	}
1581 	NInoSetSparseDisabled(NTFS_I(ino));
1582 	/* The size of FILE_AttrDef must be above 0 and fit inside 31 bits. */
1583 	i_size = i_size_read(ino);
1584 	if (i_size <= 0 || i_size > 0x7fffffff)
1585 		goto iput_failed;
1586 	vol->attrdef = (ATTR_DEF*)ntfs_malloc_nofs(i_size);
1587 	if (!vol->attrdef)
1588 		goto iput_failed;
1589 	index = 0;
1590 	max_index = i_size >> PAGE_CACHE_SHIFT;
1591 	size = PAGE_CACHE_SIZE;
1592 	while (index < max_index) {
1593 		/* Read the attrdef table and copy it into the linear buffer. */
1594 read_partial_attrdef_page:
1595 		page = ntfs_map_page(ino->i_mapping, index);
1596 		if (IS_ERR(page))
1597 			goto free_iput_failed;
1598 		memcpy((u8*)vol->attrdef + (index++ << PAGE_CACHE_SHIFT),
1599 				page_address(page), size);
1600 		ntfs_unmap_page(page);
1601 	};
1602 	if (size == PAGE_CACHE_SIZE) {
1603 		size = i_size & ~PAGE_CACHE_MASK;
1604 		if (size)
1605 			goto read_partial_attrdef_page;
1606 	}
1607 	vol->attrdef_size = i_size;
1608 	ntfs_debug("Read %llu bytes from $AttrDef.", i_size);
1609 	iput(ino);
1610 	return true;
1611 free_iput_failed:
1612 	ntfs_free(vol->attrdef);
1613 	vol->attrdef = NULL;
1614 iput_failed:
1615 	iput(ino);
1616 failed:
1617 	ntfs_error(sb, "Failed to initialize attribute definition table.");
1618 	return false;
1619 }
1620 
1621 #endif /* NTFS_RW */
1622 
1623 /**
1624  * load_and_init_upcase - load the upcase table for an ntfs volume
1625  * @vol:	ntfs super block describing device whose upcase to load
1626  *
1627  * Return 'true' on success or 'false' on error.
1628  */
1629 static bool load_and_init_upcase(ntfs_volume *vol)
1630 {
1631 	loff_t i_size;
1632 	struct super_block *sb = vol->sb;
1633 	struct inode *ino;
1634 	struct page *page;
1635 	pgoff_t index, max_index;
1636 	unsigned int size;
1637 	int i, max;
1638 
1639 	ntfs_debug("Entering.");
1640 	/* Read upcase table and setup vol->upcase and vol->upcase_len. */
1641 	ino = ntfs_iget(sb, FILE_UpCase);
1642 	if (IS_ERR(ino) || is_bad_inode(ino)) {
1643 		if (!IS_ERR(ino))
1644 			iput(ino);
1645 		goto upcase_failed;
1646 	}
1647 	/*
1648 	 * The upcase size must not be above 64k Unicode characters, must not
1649 	 * be zero and must be a multiple of sizeof(ntfschar).
1650 	 */
1651 	i_size = i_size_read(ino);
1652 	if (!i_size || i_size & (sizeof(ntfschar) - 1) ||
1653 			i_size > 64ULL * 1024 * sizeof(ntfschar))
1654 		goto iput_upcase_failed;
1655 	vol->upcase = (ntfschar*)ntfs_malloc_nofs(i_size);
1656 	if (!vol->upcase)
1657 		goto iput_upcase_failed;
1658 	index = 0;
1659 	max_index = i_size >> PAGE_CACHE_SHIFT;
1660 	size = PAGE_CACHE_SIZE;
1661 	while (index < max_index) {
1662 		/* Read the upcase table and copy it into the linear buffer. */
1663 read_partial_upcase_page:
1664 		page = ntfs_map_page(ino->i_mapping, index);
1665 		if (IS_ERR(page))
1666 			goto iput_upcase_failed;
1667 		memcpy((char*)vol->upcase + (index++ << PAGE_CACHE_SHIFT),
1668 				page_address(page), size);
1669 		ntfs_unmap_page(page);
1670 	};
1671 	if (size == PAGE_CACHE_SIZE) {
1672 		size = i_size & ~PAGE_CACHE_MASK;
1673 		if (size)
1674 			goto read_partial_upcase_page;
1675 	}
1676 	vol->upcase_len = i_size >> UCHAR_T_SIZE_BITS;
1677 	ntfs_debug("Read %llu bytes from $UpCase (expected %zu bytes).",
1678 			i_size, 64 * 1024 * sizeof(ntfschar));
1679 	iput(ino);
1680 	mutex_lock(&ntfs_lock);
1681 	if (!default_upcase) {
1682 		ntfs_debug("Using volume specified $UpCase since default is "
1683 				"not present.");
1684 		mutex_unlock(&ntfs_lock);
1685 		return true;
1686 	}
1687 	max = default_upcase_len;
1688 	if (max > vol->upcase_len)
1689 		max = vol->upcase_len;
1690 	for (i = 0; i < max; i++)
1691 		if (vol->upcase[i] != default_upcase[i])
1692 			break;
1693 	if (i == max) {
1694 		ntfs_free(vol->upcase);
1695 		vol->upcase = default_upcase;
1696 		vol->upcase_len = max;
1697 		ntfs_nr_upcase_users++;
1698 		mutex_unlock(&ntfs_lock);
1699 		ntfs_debug("Volume specified $UpCase matches default. Using "
1700 				"default.");
1701 		return true;
1702 	}
1703 	mutex_unlock(&ntfs_lock);
1704 	ntfs_debug("Using volume specified $UpCase since it does not match "
1705 			"the default.");
1706 	return true;
1707 iput_upcase_failed:
1708 	iput(ino);
1709 	ntfs_free(vol->upcase);
1710 	vol->upcase = NULL;
1711 upcase_failed:
1712 	mutex_lock(&ntfs_lock);
1713 	if (default_upcase) {
1714 		vol->upcase = default_upcase;
1715 		vol->upcase_len = default_upcase_len;
1716 		ntfs_nr_upcase_users++;
1717 		mutex_unlock(&ntfs_lock);
1718 		ntfs_error(sb, "Failed to load $UpCase from the volume. Using "
1719 				"default.");
1720 		return true;
1721 	}
1722 	mutex_unlock(&ntfs_lock);
1723 	ntfs_error(sb, "Failed to initialize upcase table.");
1724 	return false;
1725 }
1726 
1727 /*
1728  * The lcn and mft bitmap inodes are NTFS-internal inodes with
1729  * their own special locking rules:
1730  */
1731 static struct lock_class_key
1732 	lcnbmp_runlist_lock_key, lcnbmp_mrec_lock_key,
1733 	mftbmp_runlist_lock_key, mftbmp_mrec_lock_key;
1734 
1735 /**
1736  * load_system_files - open the system files using normal functions
1737  * @vol:	ntfs super block describing device whose system files to load
1738  *
1739  * Open the system files with normal access functions and complete setting up
1740  * the ntfs super block @vol.
1741  *
1742  * Return 'true' on success or 'false' on error.
1743  */
1744 static bool load_system_files(ntfs_volume *vol)
1745 {
1746 	struct super_block *sb = vol->sb;
1747 	MFT_RECORD *m;
1748 	VOLUME_INFORMATION *vi;
1749 	ntfs_attr_search_ctx *ctx;
1750 #ifdef NTFS_RW
1751 	RESTART_PAGE_HEADER *rp;
1752 	int err;
1753 #endif /* NTFS_RW */
1754 
1755 	ntfs_debug("Entering.");
1756 #ifdef NTFS_RW
1757 	/* Get mft mirror inode compare the contents of $MFT and $MFTMirr. */
1758 	if (!load_and_init_mft_mirror(vol) || !check_mft_mirror(vol)) {
1759 		static const char *es1 = "Failed to load $MFTMirr";
1760 		static const char *es2 = "$MFTMirr does not match $MFT";
1761 		static const char *es3 = ".  Run ntfsfix and/or chkdsk.";
1762 
1763 		/* If a read-write mount, convert it to a read-only mount. */
1764 		if (!(sb->s_flags & MS_RDONLY)) {
1765 			if (!(vol->on_errors & (ON_ERRORS_REMOUNT_RO |
1766 					ON_ERRORS_CONTINUE))) {
1767 				ntfs_error(sb, "%s and neither on_errors="
1768 						"continue nor on_errors="
1769 						"remount-ro was specified%s",
1770 						!vol->mftmirr_ino ? es1 : es2,
1771 						es3);
1772 				goto iput_mirr_err_out;
1773 			}
1774 			sb->s_flags |= MS_RDONLY;
1775 			ntfs_error(sb, "%s.  Mounting read-only%s",
1776 					!vol->mftmirr_ino ? es1 : es2, es3);
1777 		} else
1778 			ntfs_warning(sb, "%s.  Will not be able to remount "
1779 					"read-write%s",
1780 					!vol->mftmirr_ino ? es1 : es2, es3);
1781 		/* This will prevent a read-write remount. */
1782 		NVolSetErrors(vol);
1783 	}
1784 #endif /* NTFS_RW */
1785 	/* Get mft bitmap attribute inode. */
1786 	vol->mftbmp_ino = ntfs_attr_iget(vol->mft_ino, AT_BITMAP, NULL, 0);
1787 	if (IS_ERR(vol->mftbmp_ino)) {
1788 		ntfs_error(sb, "Failed to load $MFT/$BITMAP attribute.");
1789 		goto iput_mirr_err_out;
1790 	}
1791 	lockdep_set_class(&NTFS_I(vol->mftbmp_ino)->runlist.lock,
1792 			   &mftbmp_runlist_lock_key);
1793 	lockdep_set_class(&NTFS_I(vol->mftbmp_ino)->mrec_lock,
1794 			   &mftbmp_mrec_lock_key);
1795 	/* Read upcase table and setup @vol->upcase and @vol->upcase_len. */
1796 	if (!load_and_init_upcase(vol))
1797 		goto iput_mftbmp_err_out;
1798 #ifdef NTFS_RW
1799 	/*
1800 	 * Read attribute definitions table and setup @vol->attrdef and
1801 	 * @vol->attrdef_size.
1802 	 */
1803 	if (!load_and_init_attrdef(vol))
1804 		goto iput_upcase_err_out;
1805 #endif /* NTFS_RW */
1806 	/*
1807 	 * Get the cluster allocation bitmap inode and verify the size, no
1808 	 * need for any locking at this stage as we are already running
1809 	 * exclusively as we are mount in progress task.
1810 	 */
1811 	vol->lcnbmp_ino = ntfs_iget(sb, FILE_Bitmap);
1812 	if (IS_ERR(vol->lcnbmp_ino) || is_bad_inode(vol->lcnbmp_ino)) {
1813 		if (!IS_ERR(vol->lcnbmp_ino))
1814 			iput(vol->lcnbmp_ino);
1815 		goto bitmap_failed;
1816 	}
1817 	lockdep_set_class(&NTFS_I(vol->lcnbmp_ino)->runlist.lock,
1818 			   &lcnbmp_runlist_lock_key);
1819 	lockdep_set_class(&NTFS_I(vol->lcnbmp_ino)->mrec_lock,
1820 			   &lcnbmp_mrec_lock_key);
1821 
1822 	NInoSetSparseDisabled(NTFS_I(vol->lcnbmp_ino));
1823 	if ((vol->nr_clusters + 7) >> 3 > i_size_read(vol->lcnbmp_ino)) {
1824 		iput(vol->lcnbmp_ino);
1825 bitmap_failed:
1826 		ntfs_error(sb, "Failed to load $Bitmap.");
1827 		goto iput_attrdef_err_out;
1828 	}
1829 	/*
1830 	 * Get the volume inode and setup our cache of the volume flags and
1831 	 * version.
1832 	 */
1833 	vol->vol_ino = ntfs_iget(sb, FILE_Volume);
1834 	if (IS_ERR(vol->vol_ino) || is_bad_inode(vol->vol_ino)) {
1835 		if (!IS_ERR(vol->vol_ino))
1836 			iput(vol->vol_ino);
1837 volume_failed:
1838 		ntfs_error(sb, "Failed to load $Volume.");
1839 		goto iput_lcnbmp_err_out;
1840 	}
1841 	m = map_mft_record(NTFS_I(vol->vol_ino));
1842 	if (IS_ERR(m)) {
1843 iput_volume_failed:
1844 		iput(vol->vol_ino);
1845 		goto volume_failed;
1846 	}
1847 	if (!(ctx = ntfs_attr_get_search_ctx(NTFS_I(vol->vol_ino), m))) {
1848 		ntfs_error(sb, "Failed to get attribute search context.");
1849 		goto get_ctx_vol_failed;
1850 	}
1851 	if (ntfs_attr_lookup(AT_VOLUME_INFORMATION, NULL, 0, 0, 0, NULL, 0,
1852 			ctx) || ctx->attr->non_resident || ctx->attr->flags) {
1853 err_put_vol:
1854 		ntfs_attr_put_search_ctx(ctx);
1855 get_ctx_vol_failed:
1856 		unmap_mft_record(NTFS_I(vol->vol_ino));
1857 		goto iput_volume_failed;
1858 	}
1859 	vi = (VOLUME_INFORMATION*)((char*)ctx->attr +
1860 			le16_to_cpu(ctx->attr->data.resident.value_offset));
1861 	/* Some bounds checks. */
1862 	if ((u8*)vi < (u8*)ctx->attr || (u8*)vi +
1863 			le32_to_cpu(ctx->attr->data.resident.value_length) >
1864 			(u8*)ctx->attr + le32_to_cpu(ctx->attr->length))
1865 		goto err_put_vol;
1866 	/* Copy the volume flags and version to the ntfs_volume structure. */
1867 	vol->vol_flags = vi->flags;
1868 	vol->major_ver = vi->major_ver;
1869 	vol->minor_ver = vi->minor_ver;
1870 	ntfs_attr_put_search_ctx(ctx);
1871 	unmap_mft_record(NTFS_I(vol->vol_ino));
1872 	printk(KERN_INFO "NTFS volume version %i.%i.\n", vol->major_ver,
1873 			vol->minor_ver);
1874 	if (vol->major_ver < 3 && NVolSparseEnabled(vol)) {
1875 		ntfs_warning(vol->sb, "Disabling sparse support due to NTFS "
1876 				"volume version %i.%i (need at least version "
1877 				"3.0).", vol->major_ver, vol->minor_ver);
1878 		NVolClearSparseEnabled(vol);
1879 	}
1880 #ifdef NTFS_RW
1881 	/* Make sure that no unsupported volume flags are set. */
1882 	if (vol->vol_flags & VOLUME_MUST_MOUNT_RO_MASK) {
1883 		static const char *es1a = "Volume is dirty";
1884 		static const char *es1b = "Volume has been modified by chkdsk";
1885 		static const char *es1c = "Volume has unsupported flags set";
1886 		static const char *es2a = ".  Run chkdsk and mount in Windows.";
1887 		static const char *es2b = ".  Mount in Windows.";
1888 		const char *es1, *es2;
1889 
1890 		es2 = es2a;
1891 		if (vol->vol_flags & VOLUME_IS_DIRTY)
1892 			es1 = es1a;
1893 		else if (vol->vol_flags & VOLUME_MODIFIED_BY_CHKDSK) {
1894 			es1 = es1b;
1895 			es2 = es2b;
1896 		} else {
1897 			es1 = es1c;
1898 			ntfs_warning(sb, "Unsupported volume flags 0x%x "
1899 					"encountered.",
1900 					(unsigned)le16_to_cpu(vol->vol_flags));
1901 		}
1902 		/* If a read-write mount, convert it to a read-only mount. */
1903 		if (!(sb->s_flags & MS_RDONLY)) {
1904 			if (!(vol->on_errors & (ON_ERRORS_REMOUNT_RO |
1905 					ON_ERRORS_CONTINUE))) {
1906 				ntfs_error(sb, "%s and neither on_errors="
1907 						"continue nor on_errors="
1908 						"remount-ro was specified%s",
1909 						es1, es2);
1910 				goto iput_vol_err_out;
1911 			}
1912 			sb->s_flags |= MS_RDONLY;
1913 			ntfs_error(sb, "%s.  Mounting read-only%s", es1, es2);
1914 		} else
1915 			ntfs_warning(sb, "%s.  Will not be able to remount "
1916 					"read-write%s", es1, es2);
1917 		/*
1918 		 * Do not set NVolErrors() because ntfs_remount() re-checks the
1919 		 * flags which we need to do in case any flags have changed.
1920 		 */
1921 	}
1922 	/*
1923 	 * Get the inode for the logfile, check it and determine if the volume
1924 	 * was shutdown cleanly.
1925 	 */
1926 	rp = NULL;
1927 	if (!load_and_check_logfile(vol, &rp) ||
1928 			!ntfs_is_logfile_clean(vol->logfile_ino, rp)) {
1929 		static const char *es1a = "Failed to load $LogFile";
1930 		static const char *es1b = "$LogFile is not clean";
1931 		static const char *es2 = ".  Mount in Windows.";
1932 		const char *es1;
1933 
1934 		es1 = !vol->logfile_ino ? es1a : es1b;
1935 		/* If a read-write mount, convert it to a read-only mount. */
1936 		if (!(sb->s_flags & MS_RDONLY)) {
1937 			if (!(vol->on_errors & (ON_ERRORS_REMOUNT_RO |
1938 					ON_ERRORS_CONTINUE))) {
1939 				ntfs_error(sb, "%s and neither on_errors="
1940 						"continue nor on_errors="
1941 						"remount-ro was specified%s",
1942 						es1, es2);
1943 				if (vol->logfile_ino) {
1944 					BUG_ON(!rp);
1945 					ntfs_free(rp);
1946 				}
1947 				goto iput_logfile_err_out;
1948 			}
1949 			sb->s_flags |= MS_RDONLY;
1950 			ntfs_error(sb, "%s.  Mounting read-only%s", es1, es2);
1951 		} else
1952 			ntfs_warning(sb, "%s.  Will not be able to remount "
1953 					"read-write%s", es1, es2);
1954 		/* This will prevent a read-write remount. */
1955 		NVolSetErrors(vol);
1956 	}
1957 	ntfs_free(rp);
1958 #endif /* NTFS_RW */
1959 	/* Get the root directory inode so we can do path lookups. */
1960 	vol->root_ino = ntfs_iget(sb, FILE_root);
1961 	if (IS_ERR(vol->root_ino) || is_bad_inode(vol->root_ino)) {
1962 		if (!IS_ERR(vol->root_ino))
1963 			iput(vol->root_ino);
1964 		ntfs_error(sb, "Failed to load root directory.");
1965 		goto iput_logfile_err_out;
1966 	}
1967 #ifdef NTFS_RW
1968 	/*
1969 	 * Check if Windows is suspended to disk on the target volume.  If it
1970 	 * is hibernated, we must not write *anything* to the disk so set
1971 	 * NVolErrors() without setting the dirty volume flag and mount
1972 	 * read-only.  This will prevent read-write remounting and it will also
1973 	 * prevent all writes.
1974 	 */
1975 	err = check_windows_hibernation_status(vol);
1976 	if (unlikely(err)) {
1977 		static const char *es1a = "Failed to determine if Windows is "
1978 				"hibernated";
1979 		static const char *es1b = "Windows is hibernated";
1980 		static const char *es2 = ".  Run chkdsk.";
1981 		const char *es1;
1982 
1983 		es1 = err < 0 ? es1a : es1b;
1984 		/* If a read-write mount, convert it to a read-only mount. */
1985 		if (!(sb->s_flags & MS_RDONLY)) {
1986 			if (!(vol->on_errors & (ON_ERRORS_REMOUNT_RO |
1987 					ON_ERRORS_CONTINUE))) {
1988 				ntfs_error(sb, "%s and neither on_errors="
1989 						"continue nor on_errors="
1990 						"remount-ro was specified%s",
1991 						es1, es2);
1992 				goto iput_root_err_out;
1993 			}
1994 			sb->s_flags |= MS_RDONLY;
1995 			ntfs_error(sb, "%s.  Mounting read-only%s", es1, es2);
1996 		} else
1997 			ntfs_warning(sb, "%s.  Will not be able to remount "
1998 					"read-write%s", es1, es2);
1999 		/* This will prevent a read-write remount. */
2000 		NVolSetErrors(vol);
2001 	}
2002 	/* If (still) a read-write mount, mark the volume dirty. */
2003 	if (!(sb->s_flags & MS_RDONLY) &&
2004 			ntfs_set_volume_flags(vol, VOLUME_IS_DIRTY)) {
2005 		static const char *es1 = "Failed to set dirty bit in volume "
2006 				"information flags";
2007 		static const char *es2 = ".  Run chkdsk.";
2008 
2009 		/* Convert to a read-only mount. */
2010 		if (!(vol->on_errors & (ON_ERRORS_REMOUNT_RO |
2011 				ON_ERRORS_CONTINUE))) {
2012 			ntfs_error(sb, "%s and neither on_errors=continue nor "
2013 					"on_errors=remount-ro was specified%s",
2014 					es1, es2);
2015 			goto iput_root_err_out;
2016 		}
2017 		ntfs_error(sb, "%s.  Mounting read-only%s", es1, es2);
2018 		sb->s_flags |= MS_RDONLY;
2019 		/*
2020 		 * Do not set NVolErrors() because ntfs_remount() might manage
2021 		 * to set the dirty flag in which case all would be well.
2022 		 */
2023 	}
2024 #if 0
2025 	// TODO: Enable this code once we start modifying anything that is
2026 	//	 different between NTFS 1.2 and 3.x...
2027 	/*
2028 	 * If (still) a read-write mount, set the NT4 compatibility flag on
2029 	 * newer NTFS version volumes.
2030 	 */
2031 	if (!(sb->s_flags & MS_RDONLY) && (vol->major_ver > 1) &&
2032 			ntfs_set_volume_flags(vol, VOLUME_MOUNTED_ON_NT4)) {
2033 		static const char *es1 = "Failed to set NT4 compatibility flag";
2034 		static const char *es2 = ".  Run chkdsk.";
2035 
2036 		/* Convert to a read-only mount. */
2037 		if (!(vol->on_errors & (ON_ERRORS_REMOUNT_RO |
2038 				ON_ERRORS_CONTINUE))) {
2039 			ntfs_error(sb, "%s and neither on_errors=continue nor "
2040 					"on_errors=remount-ro was specified%s",
2041 					es1, es2);
2042 			goto iput_root_err_out;
2043 		}
2044 		ntfs_error(sb, "%s.  Mounting read-only%s", es1, es2);
2045 		sb->s_flags |= MS_RDONLY;
2046 		NVolSetErrors(vol);
2047 	}
2048 #endif
2049 	/* If (still) a read-write mount, empty the logfile. */
2050 	if (!(sb->s_flags & MS_RDONLY) &&
2051 			!ntfs_empty_logfile(vol->logfile_ino)) {
2052 		static const char *es1 = "Failed to empty $LogFile";
2053 		static const char *es2 = ".  Mount in Windows.";
2054 
2055 		/* Convert to a read-only mount. */
2056 		if (!(vol->on_errors & (ON_ERRORS_REMOUNT_RO |
2057 				ON_ERRORS_CONTINUE))) {
2058 			ntfs_error(sb, "%s and neither on_errors=continue nor "
2059 					"on_errors=remount-ro was specified%s",
2060 					es1, es2);
2061 			goto iput_root_err_out;
2062 		}
2063 		ntfs_error(sb, "%s.  Mounting read-only%s", es1, es2);
2064 		sb->s_flags |= MS_RDONLY;
2065 		NVolSetErrors(vol);
2066 	}
2067 #endif /* NTFS_RW */
2068 	/* If on NTFS versions before 3.0, we are done. */
2069 	if (unlikely(vol->major_ver < 3))
2070 		return true;
2071 	/* NTFS 3.0+ specific initialization. */
2072 	/* Get the security descriptors inode. */
2073 	vol->secure_ino = ntfs_iget(sb, FILE_Secure);
2074 	if (IS_ERR(vol->secure_ino) || is_bad_inode(vol->secure_ino)) {
2075 		if (!IS_ERR(vol->secure_ino))
2076 			iput(vol->secure_ino);
2077 		ntfs_error(sb, "Failed to load $Secure.");
2078 		goto iput_root_err_out;
2079 	}
2080 	// TODO: Initialize security.
2081 	/* Get the extended system files' directory inode. */
2082 	vol->extend_ino = ntfs_iget(sb, FILE_Extend);
2083 	if (IS_ERR(vol->extend_ino) || is_bad_inode(vol->extend_ino)) {
2084 		if (!IS_ERR(vol->extend_ino))
2085 			iput(vol->extend_ino);
2086 		ntfs_error(sb, "Failed to load $Extend.");
2087 		goto iput_sec_err_out;
2088 	}
2089 #ifdef NTFS_RW
2090 	/* Find the quota file, load it if present, and set it up. */
2091 	if (!load_and_init_quota(vol)) {
2092 		static const char *es1 = "Failed to load $Quota";
2093 		static const char *es2 = ".  Run chkdsk.";
2094 
2095 		/* If a read-write mount, convert it to a read-only mount. */
2096 		if (!(sb->s_flags & MS_RDONLY)) {
2097 			if (!(vol->on_errors & (ON_ERRORS_REMOUNT_RO |
2098 					ON_ERRORS_CONTINUE))) {
2099 				ntfs_error(sb, "%s and neither on_errors="
2100 						"continue nor on_errors="
2101 						"remount-ro was specified%s",
2102 						es1, es2);
2103 				goto iput_quota_err_out;
2104 			}
2105 			sb->s_flags |= MS_RDONLY;
2106 			ntfs_error(sb, "%s.  Mounting read-only%s", es1, es2);
2107 		} else
2108 			ntfs_warning(sb, "%s.  Will not be able to remount "
2109 					"read-write%s", es1, es2);
2110 		/* This will prevent a read-write remount. */
2111 		NVolSetErrors(vol);
2112 	}
2113 	/* If (still) a read-write mount, mark the quotas out of date. */
2114 	if (!(sb->s_flags & MS_RDONLY) &&
2115 			!ntfs_mark_quotas_out_of_date(vol)) {
2116 		static const char *es1 = "Failed to mark quotas out of date";
2117 		static const char *es2 = ".  Run chkdsk.";
2118 
2119 		/* Convert to a read-only mount. */
2120 		if (!(vol->on_errors & (ON_ERRORS_REMOUNT_RO |
2121 				ON_ERRORS_CONTINUE))) {
2122 			ntfs_error(sb, "%s and neither on_errors=continue nor "
2123 					"on_errors=remount-ro was specified%s",
2124 					es1, es2);
2125 			goto iput_quota_err_out;
2126 		}
2127 		ntfs_error(sb, "%s.  Mounting read-only%s", es1, es2);
2128 		sb->s_flags |= MS_RDONLY;
2129 		NVolSetErrors(vol);
2130 	}
2131 	/*
2132 	 * Find the transaction log file ($UsnJrnl), load it if present, check
2133 	 * it, and set it up.
2134 	 */
2135 	if (!load_and_init_usnjrnl(vol)) {
2136 		static const char *es1 = "Failed to load $UsnJrnl";
2137 		static const char *es2 = ".  Run chkdsk.";
2138 
2139 		/* If a read-write mount, convert it to a read-only mount. */
2140 		if (!(sb->s_flags & MS_RDONLY)) {
2141 			if (!(vol->on_errors & (ON_ERRORS_REMOUNT_RO |
2142 					ON_ERRORS_CONTINUE))) {
2143 				ntfs_error(sb, "%s and neither on_errors="
2144 						"continue nor on_errors="
2145 						"remount-ro was specified%s",
2146 						es1, es2);
2147 				goto iput_usnjrnl_err_out;
2148 			}
2149 			sb->s_flags |= MS_RDONLY;
2150 			ntfs_error(sb, "%s.  Mounting read-only%s", es1, es2);
2151 		} else
2152 			ntfs_warning(sb, "%s.  Will not be able to remount "
2153 					"read-write%s", es1, es2);
2154 		/* This will prevent a read-write remount. */
2155 		NVolSetErrors(vol);
2156 	}
2157 	/* If (still) a read-write mount, stamp the transaction log. */
2158 	if (!(sb->s_flags & MS_RDONLY) && !ntfs_stamp_usnjrnl(vol)) {
2159 		static const char *es1 = "Failed to stamp transaction log "
2160 				"($UsnJrnl)";
2161 		static const char *es2 = ".  Run chkdsk.";
2162 
2163 		/* Convert to a read-only mount. */
2164 		if (!(vol->on_errors & (ON_ERRORS_REMOUNT_RO |
2165 				ON_ERRORS_CONTINUE))) {
2166 			ntfs_error(sb, "%s and neither on_errors=continue nor "
2167 					"on_errors=remount-ro was specified%s",
2168 					es1, es2);
2169 			goto iput_usnjrnl_err_out;
2170 		}
2171 		ntfs_error(sb, "%s.  Mounting read-only%s", es1, es2);
2172 		sb->s_flags |= MS_RDONLY;
2173 		NVolSetErrors(vol);
2174 	}
2175 #endif /* NTFS_RW */
2176 	return true;
2177 #ifdef NTFS_RW
2178 iput_usnjrnl_err_out:
2179 	if (vol->usnjrnl_j_ino)
2180 		iput(vol->usnjrnl_j_ino);
2181 	if (vol->usnjrnl_max_ino)
2182 		iput(vol->usnjrnl_max_ino);
2183 	if (vol->usnjrnl_ino)
2184 		iput(vol->usnjrnl_ino);
2185 iput_quota_err_out:
2186 	if (vol->quota_q_ino)
2187 		iput(vol->quota_q_ino);
2188 	if (vol->quota_ino)
2189 		iput(vol->quota_ino);
2190 	iput(vol->extend_ino);
2191 #endif /* NTFS_RW */
2192 iput_sec_err_out:
2193 	iput(vol->secure_ino);
2194 iput_root_err_out:
2195 	iput(vol->root_ino);
2196 iput_logfile_err_out:
2197 #ifdef NTFS_RW
2198 	if (vol->logfile_ino)
2199 		iput(vol->logfile_ino);
2200 iput_vol_err_out:
2201 #endif /* NTFS_RW */
2202 	iput(vol->vol_ino);
2203 iput_lcnbmp_err_out:
2204 	iput(vol->lcnbmp_ino);
2205 iput_attrdef_err_out:
2206 	vol->attrdef_size = 0;
2207 	if (vol->attrdef) {
2208 		ntfs_free(vol->attrdef);
2209 		vol->attrdef = NULL;
2210 	}
2211 #ifdef NTFS_RW
2212 iput_upcase_err_out:
2213 #endif /* NTFS_RW */
2214 	vol->upcase_len = 0;
2215 	mutex_lock(&ntfs_lock);
2216 	if (vol->upcase == default_upcase) {
2217 		ntfs_nr_upcase_users--;
2218 		vol->upcase = NULL;
2219 	}
2220 	mutex_unlock(&ntfs_lock);
2221 	if (vol->upcase) {
2222 		ntfs_free(vol->upcase);
2223 		vol->upcase = NULL;
2224 	}
2225 iput_mftbmp_err_out:
2226 	iput(vol->mftbmp_ino);
2227 iput_mirr_err_out:
2228 #ifdef NTFS_RW
2229 	if (vol->mftmirr_ino)
2230 		iput(vol->mftmirr_ino);
2231 #endif /* NTFS_RW */
2232 	return false;
2233 }
2234 
2235 /**
2236  * ntfs_put_super - called by the vfs to unmount a volume
2237  * @sb:		vfs superblock of volume to unmount
2238  *
2239  * ntfs_put_super() is called by the VFS (from fs/super.c::do_umount()) when
2240  * the volume is being unmounted (umount system call has been invoked) and it
2241  * releases all inodes and memory belonging to the NTFS specific part of the
2242  * super block.
2243  */
2244 static void ntfs_put_super(struct super_block *sb)
2245 {
2246 	ntfs_volume *vol = NTFS_SB(sb);
2247 
2248 	ntfs_debug("Entering.");
2249 
2250 #ifdef NTFS_RW
2251 	/*
2252 	 * Commit all inodes while they are still open in case some of them
2253 	 * cause others to be dirtied.
2254 	 */
2255 	ntfs_commit_inode(vol->vol_ino);
2256 
2257 	/* NTFS 3.0+ specific. */
2258 	if (vol->major_ver >= 3) {
2259 		if (vol->usnjrnl_j_ino)
2260 			ntfs_commit_inode(vol->usnjrnl_j_ino);
2261 		if (vol->usnjrnl_max_ino)
2262 			ntfs_commit_inode(vol->usnjrnl_max_ino);
2263 		if (vol->usnjrnl_ino)
2264 			ntfs_commit_inode(vol->usnjrnl_ino);
2265 		if (vol->quota_q_ino)
2266 			ntfs_commit_inode(vol->quota_q_ino);
2267 		if (vol->quota_ino)
2268 			ntfs_commit_inode(vol->quota_ino);
2269 		if (vol->extend_ino)
2270 			ntfs_commit_inode(vol->extend_ino);
2271 		if (vol->secure_ino)
2272 			ntfs_commit_inode(vol->secure_ino);
2273 	}
2274 
2275 	ntfs_commit_inode(vol->root_ino);
2276 
2277 	down_write(&vol->lcnbmp_lock);
2278 	ntfs_commit_inode(vol->lcnbmp_ino);
2279 	up_write(&vol->lcnbmp_lock);
2280 
2281 	down_write(&vol->mftbmp_lock);
2282 	ntfs_commit_inode(vol->mftbmp_ino);
2283 	up_write(&vol->mftbmp_lock);
2284 
2285 	if (vol->logfile_ino)
2286 		ntfs_commit_inode(vol->logfile_ino);
2287 
2288 	if (vol->mftmirr_ino)
2289 		ntfs_commit_inode(vol->mftmirr_ino);
2290 	ntfs_commit_inode(vol->mft_ino);
2291 
2292 	/*
2293 	 * If a read-write mount and no volume errors have occurred, mark the
2294 	 * volume clean.  Also, re-commit all affected inodes.
2295 	 */
2296 	if (!(sb->s_flags & MS_RDONLY)) {
2297 		if (!NVolErrors(vol)) {
2298 			if (ntfs_clear_volume_flags(vol, VOLUME_IS_DIRTY))
2299 				ntfs_warning(sb, "Failed to clear dirty bit "
2300 						"in volume information "
2301 						"flags.  Run chkdsk.");
2302 			ntfs_commit_inode(vol->vol_ino);
2303 			ntfs_commit_inode(vol->root_ino);
2304 			if (vol->mftmirr_ino)
2305 				ntfs_commit_inode(vol->mftmirr_ino);
2306 			ntfs_commit_inode(vol->mft_ino);
2307 		} else {
2308 			ntfs_warning(sb, "Volume has errors.  Leaving volume "
2309 					"marked dirty.  Run chkdsk.");
2310 		}
2311 	}
2312 #endif /* NTFS_RW */
2313 
2314 	iput(vol->vol_ino);
2315 	vol->vol_ino = NULL;
2316 
2317 	/* NTFS 3.0+ specific clean up. */
2318 	if (vol->major_ver >= 3) {
2319 #ifdef NTFS_RW
2320 		if (vol->usnjrnl_j_ino) {
2321 			iput(vol->usnjrnl_j_ino);
2322 			vol->usnjrnl_j_ino = NULL;
2323 		}
2324 		if (vol->usnjrnl_max_ino) {
2325 			iput(vol->usnjrnl_max_ino);
2326 			vol->usnjrnl_max_ino = NULL;
2327 		}
2328 		if (vol->usnjrnl_ino) {
2329 			iput(vol->usnjrnl_ino);
2330 			vol->usnjrnl_ino = NULL;
2331 		}
2332 		if (vol->quota_q_ino) {
2333 			iput(vol->quota_q_ino);
2334 			vol->quota_q_ino = NULL;
2335 		}
2336 		if (vol->quota_ino) {
2337 			iput(vol->quota_ino);
2338 			vol->quota_ino = NULL;
2339 		}
2340 #endif /* NTFS_RW */
2341 		if (vol->extend_ino) {
2342 			iput(vol->extend_ino);
2343 			vol->extend_ino = NULL;
2344 		}
2345 		if (vol->secure_ino) {
2346 			iput(vol->secure_ino);
2347 			vol->secure_ino = NULL;
2348 		}
2349 	}
2350 
2351 	iput(vol->root_ino);
2352 	vol->root_ino = NULL;
2353 
2354 	down_write(&vol->lcnbmp_lock);
2355 	iput(vol->lcnbmp_ino);
2356 	vol->lcnbmp_ino = NULL;
2357 	up_write(&vol->lcnbmp_lock);
2358 
2359 	down_write(&vol->mftbmp_lock);
2360 	iput(vol->mftbmp_ino);
2361 	vol->mftbmp_ino = NULL;
2362 	up_write(&vol->mftbmp_lock);
2363 
2364 #ifdef NTFS_RW
2365 	if (vol->logfile_ino) {
2366 		iput(vol->logfile_ino);
2367 		vol->logfile_ino = NULL;
2368 	}
2369 	if (vol->mftmirr_ino) {
2370 		/* Re-commit the mft mirror and mft just in case. */
2371 		ntfs_commit_inode(vol->mftmirr_ino);
2372 		ntfs_commit_inode(vol->mft_ino);
2373 		iput(vol->mftmirr_ino);
2374 		vol->mftmirr_ino = NULL;
2375 	}
2376 	/*
2377 	 * We should have no dirty inodes left, due to
2378 	 * mft.c::ntfs_mft_writepage() cleaning all the dirty pages as
2379 	 * the underlying mft records are written out and cleaned.
2380 	 */
2381 	ntfs_commit_inode(vol->mft_ino);
2382 	write_inode_now(vol->mft_ino, 1);
2383 #endif /* NTFS_RW */
2384 
2385 	iput(vol->mft_ino);
2386 	vol->mft_ino = NULL;
2387 
2388 	/* Throw away the table of attribute definitions. */
2389 	vol->attrdef_size = 0;
2390 	if (vol->attrdef) {
2391 		ntfs_free(vol->attrdef);
2392 		vol->attrdef = NULL;
2393 	}
2394 	vol->upcase_len = 0;
2395 	/*
2396 	 * Destroy the global default upcase table if necessary.  Also decrease
2397 	 * the number of upcase users if we are a user.
2398 	 */
2399 	mutex_lock(&ntfs_lock);
2400 	if (vol->upcase == default_upcase) {
2401 		ntfs_nr_upcase_users--;
2402 		vol->upcase = NULL;
2403 	}
2404 	if (!ntfs_nr_upcase_users && default_upcase) {
2405 		ntfs_free(default_upcase);
2406 		default_upcase = NULL;
2407 	}
2408 	if (vol->cluster_size <= 4096 && !--ntfs_nr_compression_users)
2409 		free_compression_buffers();
2410 	mutex_unlock(&ntfs_lock);
2411 	if (vol->upcase) {
2412 		ntfs_free(vol->upcase);
2413 		vol->upcase = NULL;
2414 	}
2415 
2416 	unload_nls(vol->nls_map);
2417 
2418 	sb->s_fs_info = NULL;
2419 	kfree(vol);
2420 }
2421 
2422 /**
2423  * get_nr_free_clusters - return the number of free clusters on a volume
2424  * @vol:	ntfs volume for which to obtain free cluster count
2425  *
2426  * Calculate the number of free clusters on the mounted NTFS volume @vol. We
2427  * actually calculate the number of clusters in use instead because this
2428  * allows us to not care about partial pages as these will be just zero filled
2429  * and hence not be counted as allocated clusters.
2430  *
2431  * The only particularity is that clusters beyond the end of the logical ntfs
2432  * volume will be marked as allocated to prevent errors which means we have to
2433  * discount those at the end. This is important as the cluster bitmap always
2434  * has a size in multiples of 8 bytes, i.e. up to 63 clusters could be outside
2435  * the logical volume and marked in use when they are not as they do not exist.
2436  *
2437  * If any pages cannot be read we assume all clusters in the erroring pages are
2438  * in use. This means we return an underestimate on errors which is better than
2439  * an overestimate.
2440  */
2441 static s64 get_nr_free_clusters(ntfs_volume *vol)
2442 {
2443 	s64 nr_free = vol->nr_clusters;
2444 	struct address_space *mapping = vol->lcnbmp_ino->i_mapping;
2445 	struct page *page;
2446 	pgoff_t index, max_index;
2447 
2448 	ntfs_debug("Entering.");
2449 	/* Serialize accesses to the cluster bitmap. */
2450 	down_read(&vol->lcnbmp_lock);
2451 	/*
2452 	 * Convert the number of bits into bytes rounded up, then convert into
2453 	 * multiples of PAGE_CACHE_SIZE, rounding up so that if we have one
2454 	 * full and one partial page max_index = 2.
2455 	 */
2456 	max_index = (((vol->nr_clusters + 7) >> 3) + PAGE_CACHE_SIZE - 1) >>
2457 			PAGE_CACHE_SHIFT;
2458 	/* Use multiples of 4 bytes, thus max_size is PAGE_CACHE_SIZE / 4. */
2459 	ntfs_debug("Reading $Bitmap, max_index = 0x%lx, max_size = 0x%lx.",
2460 			max_index, PAGE_CACHE_SIZE / 4);
2461 	for (index = 0; index < max_index; index++) {
2462 		unsigned long *kaddr;
2463 
2464 		/*
2465 		 * Read the page from page cache, getting it from backing store
2466 		 * if necessary, and increment the use count.
2467 		 */
2468 		page = read_mapping_page(mapping, index, NULL);
2469 		/* Ignore pages which errored synchronously. */
2470 		if (IS_ERR(page)) {
2471 			ntfs_debug("read_mapping_page() error. Skipping "
2472 					"page (index 0x%lx).", index);
2473 			nr_free -= PAGE_CACHE_SIZE * 8;
2474 			continue;
2475 		}
2476 		kaddr = kmap_atomic(page);
2477 		/*
2478 		 * Subtract the number of set bits. If this
2479 		 * is the last page and it is partial we don't really care as
2480 		 * it just means we do a little extra work but it won't affect
2481 		 * the result as all out of range bytes are set to zero by
2482 		 * ntfs_readpage().
2483 		 */
2484 		nr_free -= bitmap_weight(kaddr,
2485 					PAGE_CACHE_SIZE * BITS_PER_BYTE);
2486 		kunmap_atomic(kaddr);
2487 		page_cache_release(page);
2488 	}
2489 	ntfs_debug("Finished reading $Bitmap, last index = 0x%lx.", index - 1);
2490 	/*
2491 	 * Fixup for eventual bits outside logical ntfs volume (see function
2492 	 * description above).
2493 	 */
2494 	if (vol->nr_clusters & 63)
2495 		nr_free += 64 - (vol->nr_clusters & 63);
2496 	up_read(&vol->lcnbmp_lock);
2497 	/* If errors occurred we may well have gone below zero, fix this. */
2498 	if (nr_free < 0)
2499 		nr_free = 0;
2500 	ntfs_debug("Exiting.");
2501 	return nr_free;
2502 }
2503 
2504 /**
2505  * __get_nr_free_mft_records - return the number of free inodes on a volume
2506  * @vol:	ntfs volume for which to obtain free inode count
2507  * @nr_free:	number of mft records in filesystem
2508  * @max_index:	maximum number of pages containing set bits
2509  *
2510  * Calculate the number of free mft records (inodes) on the mounted NTFS
2511  * volume @vol. We actually calculate the number of mft records in use instead
2512  * because this allows us to not care about partial pages as these will be just
2513  * zero filled and hence not be counted as allocated mft record.
2514  *
2515  * If any pages cannot be read we assume all mft records in the erroring pages
2516  * are in use. This means we return an underestimate on errors which is better
2517  * than an overestimate.
2518  *
2519  * NOTE: Caller must hold mftbmp_lock rw_semaphore for reading or writing.
2520  */
2521 static unsigned long __get_nr_free_mft_records(ntfs_volume *vol,
2522 		s64 nr_free, const pgoff_t max_index)
2523 {
2524 	struct address_space *mapping = vol->mftbmp_ino->i_mapping;
2525 	struct page *page;
2526 	pgoff_t index;
2527 
2528 	ntfs_debug("Entering.");
2529 	/* Use multiples of 4 bytes, thus max_size is PAGE_CACHE_SIZE / 4. */
2530 	ntfs_debug("Reading $MFT/$BITMAP, max_index = 0x%lx, max_size = "
2531 			"0x%lx.", max_index, PAGE_CACHE_SIZE / 4);
2532 	for (index = 0; index < max_index; index++) {
2533 		unsigned long *kaddr;
2534 
2535 		/*
2536 		 * Read the page from page cache, getting it from backing store
2537 		 * if necessary, and increment the use count.
2538 		 */
2539 		page = read_mapping_page(mapping, index, NULL);
2540 		/* Ignore pages which errored synchronously. */
2541 		if (IS_ERR(page)) {
2542 			ntfs_debug("read_mapping_page() error. Skipping "
2543 					"page (index 0x%lx).", index);
2544 			nr_free -= PAGE_CACHE_SIZE * 8;
2545 			continue;
2546 		}
2547 		kaddr = kmap_atomic(page);
2548 		/*
2549 		 * Subtract the number of set bits. If this
2550 		 * is the last page and it is partial we don't really care as
2551 		 * it just means we do a little extra work but it won't affect
2552 		 * the result as all out of range bytes are set to zero by
2553 		 * ntfs_readpage().
2554 		 */
2555 		nr_free -= bitmap_weight(kaddr,
2556 					PAGE_CACHE_SIZE * BITS_PER_BYTE);
2557 		kunmap_atomic(kaddr);
2558 		page_cache_release(page);
2559 	}
2560 	ntfs_debug("Finished reading $MFT/$BITMAP, last index = 0x%lx.",
2561 			index - 1);
2562 	/* If errors occurred we may well have gone below zero, fix this. */
2563 	if (nr_free < 0)
2564 		nr_free = 0;
2565 	ntfs_debug("Exiting.");
2566 	return nr_free;
2567 }
2568 
2569 /**
2570  * ntfs_statfs - return information about mounted NTFS volume
2571  * @dentry:	dentry from mounted volume
2572  * @sfs:	statfs structure in which to return the information
2573  *
2574  * Return information about the mounted NTFS volume @dentry in the statfs structure
2575  * pointed to by @sfs (this is initialized with zeros before ntfs_statfs is
2576  * called). We interpret the values to be correct of the moment in time at
2577  * which we are called. Most values are variable otherwise and this isn't just
2578  * the free values but the totals as well. For example we can increase the
2579  * total number of file nodes if we run out and we can keep doing this until
2580  * there is no more space on the volume left at all.
2581  *
2582  * Called from vfs_statfs which is used to handle the statfs, fstatfs, and
2583  * ustat system calls.
2584  *
2585  * Return 0 on success or -errno on error.
2586  */
2587 static int ntfs_statfs(struct dentry *dentry, struct kstatfs *sfs)
2588 {
2589 	struct super_block *sb = dentry->d_sb;
2590 	s64 size;
2591 	ntfs_volume *vol = NTFS_SB(sb);
2592 	ntfs_inode *mft_ni = NTFS_I(vol->mft_ino);
2593 	pgoff_t max_index;
2594 	unsigned long flags;
2595 
2596 	ntfs_debug("Entering.");
2597 	/* Type of filesystem. */
2598 	sfs->f_type   = NTFS_SB_MAGIC;
2599 	/* Optimal transfer block size. */
2600 	sfs->f_bsize  = PAGE_CACHE_SIZE;
2601 	/*
2602 	 * Total data blocks in filesystem in units of f_bsize and since
2603 	 * inodes are also stored in data blocs ($MFT is a file) this is just
2604 	 * the total clusters.
2605 	 */
2606 	sfs->f_blocks = vol->nr_clusters << vol->cluster_size_bits >>
2607 				PAGE_CACHE_SHIFT;
2608 	/* Free data blocks in filesystem in units of f_bsize. */
2609 	size	      = get_nr_free_clusters(vol) << vol->cluster_size_bits >>
2610 				PAGE_CACHE_SHIFT;
2611 	if (size < 0LL)
2612 		size = 0LL;
2613 	/* Free blocks avail to non-superuser, same as above on NTFS. */
2614 	sfs->f_bavail = sfs->f_bfree = size;
2615 	/* Serialize accesses to the inode bitmap. */
2616 	down_read(&vol->mftbmp_lock);
2617 	read_lock_irqsave(&mft_ni->size_lock, flags);
2618 	size = i_size_read(vol->mft_ino) >> vol->mft_record_size_bits;
2619 	/*
2620 	 * Convert the maximum number of set bits into bytes rounded up, then
2621 	 * convert into multiples of PAGE_CACHE_SIZE, rounding up so that if we
2622 	 * have one full and one partial page max_index = 2.
2623 	 */
2624 	max_index = ((((mft_ni->initialized_size >> vol->mft_record_size_bits)
2625 			+ 7) >> 3) + PAGE_CACHE_SIZE - 1) >> PAGE_CACHE_SHIFT;
2626 	read_unlock_irqrestore(&mft_ni->size_lock, flags);
2627 	/* Number of inodes in filesystem (at this point in time). */
2628 	sfs->f_files = size;
2629 	/* Free inodes in fs (based on current total count). */
2630 	sfs->f_ffree = __get_nr_free_mft_records(vol, size, max_index);
2631 	up_read(&vol->mftbmp_lock);
2632 	/*
2633 	 * File system id. This is extremely *nix flavour dependent and even
2634 	 * within Linux itself all fs do their own thing. I interpret this to
2635 	 * mean a unique id associated with the mounted fs and not the id
2636 	 * associated with the filesystem driver, the latter is already given
2637 	 * by the filesystem type in sfs->f_type. Thus we use the 64-bit
2638 	 * volume serial number splitting it into two 32-bit parts. We enter
2639 	 * the least significant 32-bits in f_fsid[0] and the most significant
2640 	 * 32-bits in f_fsid[1].
2641 	 */
2642 	sfs->f_fsid.val[0] = vol->serial_no & 0xffffffff;
2643 	sfs->f_fsid.val[1] = (vol->serial_no >> 32) & 0xffffffff;
2644 	/* Maximum length of filenames. */
2645 	sfs->f_namelen	   = NTFS_MAX_NAME_LEN;
2646 	return 0;
2647 }
2648 
2649 #ifdef NTFS_RW
2650 static int ntfs_write_inode(struct inode *vi, struct writeback_control *wbc)
2651 {
2652 	return __ntfs_write_inode(vi, wbc->sync_mode == WB_SYNC_ALL);
2653 }
2654 #endif
2655 
2656 /**
2657  * The complete super operations.
2658  */
2659 static const struct super_operations ntfs_sops = {
2660 	.alloc_inode	= ntfs_alloc_big_inode,	  /* VFS: Allocate new inode. */
2661 	.destroy_inode	= ntfs_destroy_big_inode, /* VFS: Deallocate inode. */
2662 #ifdef NTFS_RW
2663 	//.dirty_inode	= NULL,			/* VFS: Called from
2664 	//					   __mark_inode_dirty(). */
2665 	.write_inode	= ntfs_write_inode,	/* VFS: Write dirty inode to
2666 						   disk. */
2667 	//.drop_inode	= NULL,			/* VFS: Called just after the
2668 	//					   inode reference count has
2669 	//					   been decreased to zero.
2670 	//					   NOTE: The inode lock is
2671 	//					   held. See fs/inode.c::
2672 	//					   generic_drop_inode(). */
2673 	//.delete_inode	= NULL,			/* VFS: Delete inode from disk.
2674 	//					   Called when i_count becomes
2675 	//					   0 and i_nlink is also 0. */
2676 	//.write_super	= NULL,			/* Flush dirty super block to
2677 	//					   disk. */
2678 	//.sync_fs	= NULL,			/* ? */
2679 	//.write_super_lockfs	= NULL,		/* ? */
2680 	//.unlockfs	= NULL,			/* ? */
2681 #endif /* NTFS_RW */
2682 	.put_super	= ntfs_put_super,	/* Syscall: umount. */
2683 	.statfs		= ntfs_statfs,		/* Syscall: statfs */
2684 	.remount_fs	= ntfs_remount,		/* Syscall: mount -o remount. */
2685 	.evict_inode	= ntfs_evict_big_inode,	/* VFS: Called when an inode is
2686 						   removed from memory. */
2687 	//.umount_begin	= NULL,			/* Forced umount. */
2688 	.show_options	= ntfs_show_options,	/* Show mount options in
2689 						   proc. */
2690 };
2691 
2692 /**
2693  * ntfs_fill_super - mount an ntfs filesystem
2694  * @sb:		super block of ntfs filesystem to mount
2695  * @opt:	string containing the mount options
2696  * @silent:	silence error output
2697  *
2698  * ntfs_fill_super() is called by the VFS to mount the device described by @sb
2699  * with the mount otions in @data with the NTFS filesystem.
2700  *
2701  * If @silent is true, remain silent even if errors are detected. This is used
2702  * during bootup, when the kernel tries to mount the root filesystem with all
2703  * registered filesystems one after the other until one succeeds. This implies
2704  * that all filesystems except the correct one will quite correctly and
2705  * expectedly return an error, but nobody wants to see error messages when in
2706  * fact this is what is supposed to happen.
2707  *
2708  * NOTE: @sb->s_flags contains the mount options flags.
2709  */
2710 static int ntfs_fill_super(struct super_block *sb, void *opt, const int silent)
2711 {
2712 	ntfs_volume *vol;
2713 	struct buffer_head *bh;
2714 	struct inode *tmp_ino;
2715 	int blocksize, result;
2716 
2717 	/*
2718 	 * We do a pretty difficult piece of bootstrap by reading the
2719 	 * MFT (and other metadata) from disk into memory. We'll only
2720 	 * release this metadata during umount, so the locking patterns
2721 	 * observed during bootstrap do not count. So turn off the
2722 	 * observation of locking patterns (strictly for this context
2723 	 * only) while mounting NTFS. [The validator is still active
2724 	 * otherwise, even for this context: it will for example record
2725 	 * lock class registrations.]
2726 	 */
2727 	lockdep_off();
2728 	ntfs_debug("Entering.");
2729 #ifndef NTFS_RW
2730 	sb->s_flags |= MS_RDONLY;
2731 #endif /* ! NTFS_RW */
2732 	/* Allocate a new ntfs_volume and place it in sb->s_fs_info. */
2733 	sb->s_fs_info = kmalloc(sizeof(ntfs_volume), GFP_NOFS);
2734 	vol = NTFS_SB(sb);
2735 	if (!vol) {
2736 		if (!silent)
2737 			ntfs_error(sb, "Allocation of NTFS volume structure "
2738 					"failed. Aborting mount...");
2739 		lockdep_on();
2740 		return -ENOMEM;
2741 	}
2742 	/* Initialize ntfs_volume structure. */
2743 	*vol = (ntfs_volume) {
2744 		.sb = sb,
2745 		/*
2746 		 * Default is group and other don't have any access to files or
2747 		 * directories while owner has full access. Further, files by
2748 		 * default are not executable but directories are of course
2749 		 * browseable.
2750 		 */
2751 		.fmask = 0177,
2752 		.dmask = 0077,
2753 	};
2754 	init_rwsem(&vol->mftbmp_lock);
2755 	init_rwsem(&vol->lcnbmp_lock);
2756 
2757 	/* By default, enable sparse support. */
2758 	NVolSetSparseEnabled(vol);
2759 
2760 	/* Important to get the mount options dealt with now. */
2761 	if (!parse_options(vol, (char*)opt))
2762 		goto err_out_now;
2763 
2764 	/* We support sector sizes up to the PAGE_CACHE_SIZE. */
2765 	if (bdev_logical_block_size(sb->s_bdev) > PAGE_CACHE_SIZE) {
2766 		if (!silent)
2767 			ntfs_error(sb, "Device has unsupported sector size "
2768 					"(%i).  The maximum supported sector "
2769 					"size on this architecture is %lu "
2770 					"bytes.",
2771 					bdev_logical_block_size(sb->s_bdev),
2772 					PAGE_CACHE_SIZE);
2773 		goto err_out_now;
2774 	}
2775 	/*
2776 	 * Setup the device access block size to NTFS_BLOCK_SIZE or the hard
2777 	 * sector size, whichever is bigger.
2778 	 */
2779 	blocksize = sb_min_blocksize(sb, NTFS_BLOCK_SIZE);
2780 	if (blocksize < NTFS_BLOCK_SIZE) {
2781 		if (!silent)
2782 			ntfs_error(sb, "Unable to set device block size.");
2783 		goto err_out_now;
2784 	}
2785 	BUG_ON(blocksize != sb->s_blocksize);
2786 	ntfs_debug("Set device block size to %i bytes (block size bits %i).",
2787 			blocksize, sb->s_blocksize_bits);
2788 	/* Determine the size of the device in units of block_size bytes. */
2789 	if (!i_size_read(sb->s_bdev->bd_inode)) {
2790 		if (!silent)
2791 			ntfs_error(sb, "Unable to determine device size.");
2792 		goto err_out_now;
2793 	}
2794 	vol->nr_blocks = i_size_read(sb->s_bdev->bd_inode) >>
2795 			sb->s_blocksize_bits;
2796 	/* Read the boot sector and return unlocked buffer head to it. */
2797 	if (!(bh = read_ntfs_boot_sector(sb, silent))) {
2798 		if (!silent)
2799 			ntfs_error(sb, "Not an NTFS volume.");
2800 		goto err_out_now;
2801 	}
2802 	/*
2803 	 * Extract the data from the boot sector and setup the ntfs volume
2804 	 * using it.
2805 	 */
2806 	result = parse_ntfs_boot_sector(vol, (NTFS_BOOT_SECTOR*)bh->b_data);
2807 	brelse(bh);
2808 	if (!result) {
2809 		if (!silent)
2810 			ntfs_error(sb, "Unsupported NTFS filesystem.");
2811 		goto err_out_now;
2812 	}
2813 	/*
2814 	 * If the boot sector indicates a sector size bigger than the current
2815 	 * device block size, switch the device block size to the sector size.
2816 	 * TODO: It may be possible to support this case even when the set
2817 	 * below fails, we would just be breaking up the i/o for each sector
2818 	 * into multiple blocks for i/o purposes but otherwise it should just
2819 	 * work.  However it is safer to leave disabled until someone hits this
2820 	 * error message and then we can get them to try it without the setting
2821 	 * so we know for sure that it works.
2822 	 */
2823 	if (vol->sector_size > blocksize) {
2824 		blocksize = sb_set_blocksize(sb, vol->sector_size);
2825 		if (blocksize != vol->sector_size) {
2826 			if (!silent)
2827 				ntfs_error(sb, "Unable to set device block "
2828 						"size to sector size (%i).",
2829 						vol->sector_size);
2830 			goto err_out_now;
2831 		}
2832 		BUG_ON(blocksize != sb->s_blocksize);
2833 		vol->nr_blocks = i_size_read(sb->s_bdev->bd_inode) >>
2834 				sb->s_blocksize_bits;
2835 		ntfs_debug("Changed device block size to %i bytes (block size "
2836 				"bits %i) to match volume sector size.",
2837 				blocksize, sb->s_blocksize_bits);
2838 	}
2839 	/* Initialize the cluster and mft allocators. */
2840 	ntfs_setup_allocators(vol);
2841 	/* Setup remaining fields in the super block. */
2842 	sb->s_magic = NTFS_SB_MAGIC;
2843 	/*
2844 	 * Ntfs allows 63 bits for the file size, i.e. correct would be:
2845 	 *	sb->s_maxbytes = ~0ULL >> 1;
2846 	 * But the kernel uses a long as the page cache page index which on
2847 	 * 32-bit architectures is only 32-bits. MAX_LFS_FILESIZE is kernel
2848 	 * defined to the maximum the page cache page index can cope with
2849 	 * without overflowing the index or to 2^63 - 1, whichever is smaller.
2850 	 */
2851 	sb->s_maxbytes = MAX_LFS_FILESIZE;
2852 	/* Ntfs measures time in 100ns intervals. */
2853 	sb->s_time_gran = 100;
2854 	/*
2855 	 * Now load the metadata required for the page cache and our address
2856 	 * space operations to function. We do this by setting up a specialised
2857 	 * read_inode method and then just calling the normal iget() to obtain
2858 	 * the inode for $MFT which is sufficient to allow our normal inode
2859 	 * operations and associated address space operations to function.
2860 	 */
2861 	sb->s_op = &ntfs_sops;
2862 	tmp_ino = new_inode(sb);
2863 	if (!tmp_ino) {
2864 		if (!silent)
2865 			ntfs_error(sb, "Failed to load essential metadata.");
2866 		goto err_out_now;
2867 	}
2868 	tmp_ino->i_ino = FILE_MFT;
2869 	insert_inode_hash(tmp_ino);
2870 	if (ntfs_read_inode_mount(tmp_ino) < 0) {
2871 		if (!silent)
2872 			ntfs_error(sb, "Failed to load essential metadata.");
2873 		goto iput_tmp_ino_err_out_now;
2874 	}
2875 	mutex_lock(&ntfs_lock);
2876 	/*
2877 	 * The current mount is a compression user if the cluster size is
2878 	 * less than or equal 4kiB.
2879 	 */
2880 	if (vol->cluster_size <= 4096 && !ntfs_nr_compression_users++) {
2881 		result = allocate_compression_buffers();
2882 		if (result) {
2883 			ntfs_error(NULL, "Failed to allocate buffers "
2884 					"for compression engine.");
2885 			ntfs_nr_compression_users--;
2886 			mutex_unlock(&ntfs_lock);
2887 			goto iput_tmp_ino_err_out_now;
2888 		}
2889 	}
2890 	/*
2891 	 * Generate the global default upcase table if necessary.  Also
2892 	 * temporarily increment the number of upcase users to avoid race
2893 	 * conditions with concurrent (u)mounts.
2894 	 */
2895 	if (!default_upcase)
2896 		default_upcase = generate_default_upcase();
2897 	ntfs_nr_upcase_users++;
2898 	mutex_unlock(&ntfs_lock);
2899 	/*
2900 	 * From now on, ignore @silent parameter. If we fail below this line,
2901 	 * it will be due to a corrupt fs or a system error, so we report it.
2902 	 */
2903 	/*
2904 	 * Open the system files with normal access functions and complete
2905 	 * setting up the ntfs super block.
2906 	 */
2907 	if (!load_system_files(vol)) {
2908 		ntfs_error(sb, "Failed to load system files.");
2909 		goto unl_upcase_iput_tmp_ino_err_out_now;
2910 	}
2911 
2912 	/* We grab a reference, simulating an ntfs_iget(). */
2913 	ihold(vol->root_ino);
2914 	if ((sb->s_root = d_make_root(vol->root_ino))) {
2915 		ntfs_debug("Exiting, status successful.");
2916 		/* Release the default upcase if it has no users. */
2917 		mutex_lock(&ntfs_lock);
2918 		if (!--ntfs_nr_upcase_users && default_upcase) {
2919 			ntfs_free(default_upcase);
2920 			default_upcase = NULL;
2921 		}
2922 		mutex_unlock(&ntfs_lock);
2923 		sb->s_export_op = &ntfs_export_ops;
2924 		lockdep_on();
2925 		return 0;
2926 	}
2927 	ntfs_error(sb, "Failed to allocate root directory.");
2928 	/* Clean up after the successful load_system_files() call from above. */
2929 	// TODO: Use ntfs_put_super() instead of repeating all this code...
2930 	// FIXME: Should mark the volume clean as the error is most likely
2931 	// 	  -ENOMEM.
2932 	iput(vol->vol_ino);
2933 	vol->vol_ino = NULL;
2934 	/* NTFS 3.0+ specific clean up. */
2935 	if (vol->major_ver >= 3) {
2936 #ifdef NTFS_RW
2937 		if (vol->usnjrnl_j_ino) {
2938 			iput(vol->usnjrnl_j_ino);
2939 			vol->usnjrnl_j_ino = NULL;
2940 		}
2941 		if (vol->usnjrnl_max_ino) {
2942 			iput(vol->usnjrnl_max_ino);
2943 			vol->usnjrnl_max_ino = NULL;
2944 		}
2945 		if (vol->usnjrnl_ino) {
2946 			iput(vol->usnjrnl_ino);
2947 			vol->usnjrnl_ino = NULL;
2948 		}
2949 		if (vol->quota_q_ino) {
2950 			iput(vol->quota_q_ino);
2951 			vol->quota_q_ino = NULL;
2952 		}
2953 		if (vol->quota_ino) {
2954 			iput(vol->quota_ino);
2955 			vol->quota_ino = NULL;
2956 		}
2957 #endif /* NTFS_RW */
2958 		if (vol->extend_ino) {
2959 			iput(vol->extend_ino);
2960 			vol->extend_ino = NULL;
2961 		}
2962 		if (vol->secure_ino) {
2963 			iput(vol->secure_ino);
2964 			vol->secure_ino = NULL;
2965 		}
2966 	}
2967 	iput(vol->root_ino);
2968 	vol->root_ino = NULL;
2969 	iput(vol->lcnbmp_ino);
2970 	vol->lcnbmp_ino = NULL;
2971 	iput(vol->mftbmp_ino);
2972 	vol->mftbmp_ino = NULL;
2973 #ifdef NTFS_RW
2974 	if (vol->logfile_ino) {
2975 		iput(vol->logfile_ino);
2976 		vol->logfile_ino = NULL;
2977 	}
2978 	if (vol->mftmirr_ino) {
2979 		iput(vol->mftmirr_ino);
2980 		vol->mftmirr_ino = NULL;
2981 	}
2982 #endif /* NTFS_RW */
2983 	/* Throw away the table of attribute definitions. */
2984 	vol->attrdef_size = 0;
2985 	if (vol->attrdef) {
2986 		ntfs_free(vol->attrdef);
2987 		vol->attrdef = NULL;
2988 	}
2989 	vol->upcase_len = 0;
2990 	mutex_lock(&ntfs_lock);
2991 	if (vol->upcase == default_upcase) {
2992 		ntfs_nr_upcase_users--;
2993 		vol->upcase = NULL;
2994 	}
2995 	mutex_unlock(&ntfs_lock);
2996 	if (vol->upcase) {
2997 		ntfs_free(vol->upcase);
2998 		vol->upcase = NULL;
2999 	}
3000 	if (vol->nls_map) {
3001 		unload_nls(vol->nls_map);
3002 		vol->nls_map = NULL;
3003 	}
3004 	/* Error exit code path. */
3005 unl_upcase_iput_tmp_ino_err_out_now:
3006 	/*
3007 	 * Decrease the number of upcase users and destroy the global default
3008 	 * upcase table if necessary.
3009 	 */
3010 	mutex_lock(&ntfs_lock);
3011 	if (!--ntfs_nr_upcase_users && default_upcase) {
3012 		ntfs_free(default_upcase);
3013 		default_upcase = NULL;
3014 	}
3015 	if (vol->cluster_size <= 4096 && !--ntfs_nr_compression_users)
3016 		free_compression_buffers();
3017 	mutex_unlock(&ntfs_lock);
3018 iput_tmp_ino_err_out_now:
3019 	iput(tmp_ino);
3020 	if (vol->mft_ino && vol->mft_ino != tmp_ino)
3021 		iput(vol->mft_ino);
3022 	vol->mft_ino = NULL;
3023 	/* Errors at this stage are irrelevant. */
3024 err_out_now:
3025 	sb->s_fs_info = NULL;
3026 	kfree(vol);
3027 	ntfs_debug("Failed, returning -EINVAL.");
3028 	lockdep_on();
3029 	return -EINVAL;
3030 }
3031 
3032 /*
3033  * This is a slab cache to optimize allocations and deallocations of Unicode
3034  * strings of the maximum length allowed by NTFS, which is NTFS_MAX_NAME_LEN
3035  * (255) Unicode characters + a terminating NULL Unicode character.
3036  */
3037 struct kmem_cache *ntfs_name_cache;
3038 
3039 /* Slab caches for efficient allocation/deallocation of inodes. */
3040 struct kmem_cache *ntfs_inode_cache;
3041 struct kmem_cache *ntfs_big_inode_cache;
3042 
3043 /* Init once constructor for the inode slab cache. */
3044 static void ntfs_big_inode_init_once(void *foo)
3045 {
3046 	ntfs_inode *ni = (ntfs_inode *)foo;
3047 
3048 	inode_init_once(VFS_I(ni));
3049 }
3050 
3051 /*
3052  * Slab caches to optimize allocations and deallocations of attribute search
3053  * contexts and index contexts, respectively.
3054  */
3055 struct kmem_cache *ntfs_attr_ctx_cache;
3056 struct kmem_cache *ntfs_index_ctx_cache;
3057 
3058 /* Driver wide mutex. */
3059 DEFINE_MUTEX(ntfs_lock);
3060 
3061 static struct dentry *ntfs_mount(struct file_system_type *fs_type,
3062 	int flags, const char *dev_name, void *data)
3063 {
3064 	return mount_bdev(fs_type, flags, dev_name, data, ntfs_fill_super);
3065 }
3066 
3067 static struct file_system_type ntfs_fs_type = {
3068 	.owner		= THIS_MODULE,
3069 	.name		= "ntfs",
3070 	.mount		= ntfs_mount,
3071 	.kill_sb	= kill_block_super,
3072 	.fs_flags	= FS_REQUIRES_DEV,
3073 };
3074 
3075 /* Stable names for the slab caches. */
3076 static const char ntfs_index_ctx_cache_name[] = "ntfs_index_ctx_cache";
3077 static const char ntfs_attr_ctx_cache_name[] = "ntfs_attr_ctx_cache";
3078 static const char ntfs_name_cache_name[] = "ntfs_name_cache";
3079 static const char ntfs_inode_cache_name[] = "ntfs_inode_cache";
3080 static const char ntfs_big_inode_cache_name[] = "ntfs_big_inode_cache";
3081 
3082 static int __init init_ntfs_fs(void)
3083 {
3084 	int err = 0;
3085 
3086 	/* This may be ugly but it results in pretty output so who cares. (-8 */
3087 	printk(KERN_INFO "NTFS driver " NTFS_VERSION " [Flags: R/"
3088 #ifdef NTFS_RW
3089 			"W"
3090 #else
3091 			"O"
3092 #endif
3093 #ifdef DEBUG
3094 			" DEBUG"
3095 #endif
3096 #ifdef MODULE
3097 			" MODULE"
3098 #endif
3099 			"].\n");
3100 
3101 	ntfs_debug("Debug messages are enabled.");
3102 
3103 	ntfs_index_ctx_cache = kmem_cache_create(ntfs_index_ctx_cache_name,
3104 			sizeof(ntfs_index_context), 0 /* offset */,
3105 			SLAB_HWCACHE_ALIGN, NULL /* ctor */);
3106 	if (!ntfs_index_ctx_cache) {
3107 		printk(KERN_CRIT "NTFS: Failed to create %s!\n",
3108 				ntfs_index_ctx_cache_name);
3109 		goto ictx_err_out;
3110 	}
3111 	ntfs_attr_ctx_cache = kmem_cache_create(ntfs_attr_ctx_cache_name,
3112 			sizeof(ntfs_attr_search_ctx), 0 /* offset */,
3113 			SLAB_HWCACHE_ALIGN, NULL /* ctor */);
3114 	if (!ntfs_attr_ctx_cache) {
3115 		printk(KERN_CRIT "NTFS: Failed to create %s!\n",
3116 				ntfs_attr_ctx_cache_name);
3117 		goto actx_err_out;
3118 	}
3119 
3120 	ntfs_name_cache = kmem_cache_create(ntfs_name_cache_name,
3121 			(NTFS_MAX_NAME_LEN+1) * sizeof(ntfschar), 0,
3122 			SLAB_HWCACHE_ALIGN, NULL);
3123 	if (!ntfs_name_cache) {
3124 		printk(KERN_CRIT "NTFS: Failed to create %s!\n",
3125 				ntfs_name_cache_name);
3126 		goto name_err_out;
3127 	}
3128 
3129 	ntfs_inode_cache = kmem_cache_create(ntfs_inode_cache_name,
3130 			sizeof(ntfs_inode), 0,
3131 			SLAB_RECLAIM_ACCOUNT|SLAB_MEM_SPREAD, NULL);
3132 	if (!ntfs_inode_cache) {
3133 		printk(KERN_CRIT "NTFS: Failed to create %s!\n",
3134 				ntfs_inode_cache_name);
3135 		goto inode_err_out;
3136 	}
3137 
3138 	ntfs_big_inode_cache = kmem_cache_create(ntfs_big_inode_cache_name,
3139 			sizeof(big_ntfs_inode), 0,
3140 			SLAB_HWCACHE_ALIGN|SLAB_RECLAIM_ACCOUNT|SLAB_MEM_SPREAD,
3141 			ntfs_big_inode_init_once);
3142 	if (!ntfs_big_inode_cache) {
3143 		printk(KERN_CRIT "NTFS: Failed to create %s!\n",
3144 				ntfs_big_inode_cache_name);
3145 		goto big_inode_err_out;
3146 	}
3147 
3148 	/* Register the ntfs sysctls. */
3149 	err = ntfs_sysctl(1);
3150 	if (err) {
3151 		printk(KERN_CRIT "NTFS: Failed to register NTFS sysctls!\n");
3152 		goto sysctl_err_out;
3153 	}
3154 
3155 	err = register_filesystem(&ntfs_fs_type);
3156 	if (!err) {
3157 		ntfs_debug("NTFS driver registered successfully.");
3158 		return 0; /* Success! */
3159 	}
3160 	printk(KERN_CRIT "NTFS: Failed to register NTFS filesystem driver!\n");
3161 
3162 	/* Unregister the ntfs sysctls. */
3163 	ntfs_sysctl(0);
3164 sysctl_err_out:
3165 	kmem_cache_destroy(ntfs_big_inode_cache);
3166 big_inode_err_out:
3167 	kmem_cache_destroy(ntfs_inode_cache);
3168 inode_err_out:
3169 	kmem_cache_destroy(ntfs_name_cache);
3170 name_err_out:
3171 	kmem_cache_destroy(ntfs_attr_ctx_cache);
3172 actx_err_out:
3173 	kmem_cache_destroy(ntfs_index_ctx_cache);
3174 ictx_err_out:
3175 	if (!err) {
3176 		printk(KERN_CRIT "NTFS: Aborting NTFS filesystem driver "
3177 				"registration...\n");
3178 		err = -ENOMEM;
3179 	}
3180 	return err;
3181 }
3182 
3183 static void __exit exit_ntfs_fs(void)
3184 {
3185 	ntfs_debug("Unregistering NTFS driver.");
3186 
3187 	unregister_filesystem(&ntfs_fs_type);
3188 	kmem_cache_destroy(ntfs_big_inode_cache);
3189 	kmem_cache_destroy(ntfs_inode_cache);
3190 	kmem_cache_destroy(ntfs_name_cache);
3191 	kmem_cache_destroy(ntfs_attr_ctx_cache);
3192 	kmem_cache_destroy(ntfs_index_ctx_cache);
3193 	/* Unregister the ntfs sysctls. */
3194 	ntfs_sysctl(0);
3195 }
3196 
3197 MODULE_AUTHOR("Anton Altaparmakov <anton@tuxera.com>");
3198 MODULE_DESCRIPTION("NTFS 1.2/3.x driver - Copyright (c) 2001-2011 Anton Altaparmakov and Tuxera Inc.");
3199 MODULE_VERSION(NTFS_VERSION);
3200 MODULE_LICENSE("GPL");
3201 #ifdef DEBUG
3202 module_param(debug_msgs, bint, 0);
3203 MODULE_PARM_DESC(debug_msgs, "Enable debug messages.");
3204 #endif
3205 
3206 module_init(init_ntfs_fs)
3207 module_exit(exit_ntfs_fs)
3208