~ [ source navigation ] ~ [ diff markup ] ~ [ identifier search ] ~

TOMOYO Linux Cross Reference
Linux/fs/ntfs/super.c

Version: ~ [ linux-5.12-rc7 ] ~ [ linux-5.11.13 ] ~ [ linux-5.10.29 ] ~ [ linux-5.9.16 ] ~ [ linux-5.8.18 ] ~ [ linux-5.7.19 ] ~ [ linux-5.6.19 ] ~ [ linux-5.5.19 ] ~ [ linux-5.4.111 ] ~ [ linux-5.3.18 ] ~ [ linux-5.2.21 ] ~ [ linux-5.1.21 ] ~ [ linux-5.0.21 ] ~ [ linux-4.20.17 ] ~ [ linux-4.19.186 ] ~ [ linux-4.18.20 ] ~ [ linux-4.17.19 ] ~ [ linux-4.16.18 ] ~ [ linux-4.15.18 ] ~ [ linux-4.14.230 ] ~ [ linux-4.13.16 ] ~ [ linux-4.12.14 ] ~ [ linux-4.11.12 ] ~ [ linux-4.10.17 ] ~ [ linux-4.9.266 ] ~ [ linux-4.8.17 ] ~ [ linux-4.7.10 ] ~ [ linux-4.6.7 ] ~ [ linux-4.5.7 ] ~ [ linux-4.4.266 ] ~ [ linux-4.3.6 ] ~ [ linux-4.2.8 ] ~ [ linux-4.1.52 ] ~ [ linux-4.0.9 ] ~ [ linux-3.18.140 ] ~ [ linux-3.16.85 ] ~ [ linux-3.14.79 ] ~ [ linux-3.12.74 ] ~ [ linux-3.10.108 ] ~ [ linux-2.6.32.71 ] ~ [ linux-2.6.0 ] ~ [ linux-2.4.37.11 ] ~ [ unix-v6-master ] ~ [ ccs-tools-1.8.5 ] ~ [ policy-sample ] ~
Architecture: ~ [ i386 ] ~ [ alpha ] ~ [ m68k ] ~ [ mips ] ~ [ ppc ] ~ [ sparc ] ~ [ sparc64 ] ~

  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, "") || !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         kuid_t uid = INVALID_UID;
106         kgid_t gid = INVALID_GID;
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_UID(option, variable)                               \
132         if (!strcmp(p, option)) {                                       \
133                 uid_t uid_value;                                        \
134                 if (!v || !*v)                                          \
135                         goto needs_arg;                                 \
136                 uid_value = simple_strtoul(ov = v, &v, 0);              \
137                 if (*v)                                                 \
138                         goto needs_val;                                 \
139                 variable = make_kuid(current_user_ns(), uid_value);     \
140                 if (!uid_valid(variable))                               \
141                         goto needs_val;                                 \
142         }
143 #define NTFS_GETOPT_GID(option, variable)                               \
144         if (!strcmp(p, option)) {                                       \
145                 gid_t gid_value;                                        \
146                 if (!v || !*v)                                          \
147                         goto needs_arg;                                 \
148                 gid_value = simple_strtoul(ov = v, &v, 0);              \
149                 if (*v)                                                 \
150                         goto needs_val;                                 \
151                 variable = make_kgid(current_user_ns(), gid_value);     \
152                 if (!gid_valid(variable))                               \
153                         goto needs_val;                                 \
154         }
155 #define NTFS_GETOPT_OCTAL(option, variable)                             \
156         if (!strcmp(p, option)) {                                       \
157                 if (!v || !*v)                                          \
158                         goto needs_arg;                                 \
159                 variable = simple_strtoul(ov = v, &v, 8);               \
160                 if (*v)                                                 \
161                         goto needs_val;                                 \
162         }
163 #define NTFS_GETOPT_BOOL(option, variable)                              \
164         if (!strcmp(p, option)) {                                       \
165                 bool val;                                               \
166                 if (!simple_getbool(v, &val))                           \
167                         goto needs_bool;                                \
168                 variable = val;                                         \
169         }
170 #define NTFS_GETOPT_OPTIONS_ARRAY(option, variable, opt_array)          \
171         if (!strcmp(p, option)) {                                       \
172                 int _i;                                                 \
173                 if (!v || !*v)                                          \
174                         goto needs_arg;                                 \
175                 ov = v;                                                 \
176                 if (variable == -1)                                     \
177                         variable = 0;                                   \
178                 for (_i = 0; opt_array[_i].str && *opt_array[_i].str; _i++) \
179                         if (!strcmp(opt_array[_i].str, v)) {            \
180                                 variable |= opt_array[_i].val;          \
181                                 break;                                  \
182                         }                                               \
183                 if (!opt_array[_i].str || !*opt_array[_i].str)          \
184                         goto needs_val;                                 \
185         }
186         if (!opt || !*opt)
187                 goto no_mount_options;
188         ntfs_debug("Entering with mount options string: %s", opt);
189         while ((p = strsep(&opt, ","))) {
190                 if ((v = strchr(p, '=')))
191                         *v++ = 0;
192                 NTFS_GETOPT_UID("uid", uid)
193                 else NTFS_GETOPT_GID("gid", gid)
194                 else NTFS_GETOPT_OCTAL("umask", fmask = dmask)
195                 else NTFS_GETOPT_OCTAL("fmask", fmask)
196                 else NTFS_GETOPT_OCTAL("dmask", dmask)
197                 else NTFS_GETOPT("mft_zone_multiplier", mft_zone_multiplier)
198                 else NTFS_GETOPT_WITH_DEFAULT("sloppy", sloppy, true)
199                 else NTFS_GETOPT_BOOL("show_sys_files", show_sys_files)
200                 else NTFS_GETOPT_BOOL("case_sensitive", case_sensitive)
201                 else NTFS_GETOPT_BOOL("disable_sparse", disable_sparse)
202                 else NTFS_GETOPT_OPTIONS_ARRAY("errors", on_errors,
203                                 on_errors_arr)
204                 else if (!strcmp(p, "posix") || !strcmp(p, "show_inodes"))
205                         ntfs_warning(vol->sb, "Ignoring obsolete option %s.",
206                                         p);
207                 else if (!strcmp(p, "nls") || !strcmp(p, "iocharset")) {
208                         if (!strcmp(p, "iocharset"))
209                                 ntfs_warning(vol->sb, "Option iocharset is "
210                                                 "deprecated. Please use "
211                                                 "option nls=<charsetname> in "
212                                                 "the future.");
213                         if (!v || !*v)
214                                 goto needs_arg;
215 use_utf8:
216                         old_nls = nls_map;
217                         nls_map = load_nls(v);
218                         if (!nls_map) {
219                                 if (!old_nls) {
220                                         ntfs_error(vol->sb, "NLS character set "
221                                                         "%s not found.", v);
222                                         return false;
223                                 }
224                                 ntfs_error(vol->sb, "NLS character set %s not "
225                                                 "found. Using previous one %s.",
226                                                 v, old_nls->charset);
227                                 nls_map = old_nls;
228                         } else /* nls_map */ {
229                                 unload_nls(old_nls);
230                         }
231                 } else if (!strcmp(p, "utf8")) {
232                         bool val = false;
233                         ntfs_warning(vol->sb, "Option utf8 is no longer "
234                                    "supported, using option nls=utf8. Please "
235                                    "use option nls=utf8 in the future and "
236                                    "make sure utf8 is compiled either as a "
237                                    "module or into the kernel.");
238                         if (!v || !*v)
239                                 val = true;
240                         else if (!simple_getbool(v, &val))
241                                 goto needs_bool;
242                         if (val) {
243                                 v = utf8;
244                                 goto use_utf8;
245                         }
246                 } else {
247                         ntfs_error(vol->sb, "Unrecognized mount option %s.", p);
248                         if (errors < INT_MAX)
249                                 errors++;
250                 }
251 #undef NTFS_GETOPT_OPTIONS_ARRAY
252 #undef NTFS_GETOPT_BOOL
253 #undef NTFS_GETOPT
254 #undef NTFS_GETOPT_WITH_DEFAULT
255         }
256 no_mount_options:
257         if (errors && !sloppy)
258                 return false;
259         if (sloppy)
260                 ntfs_warning(vol->sb, "Sloppy option given. Ignoring "
261                                 "unrecognized mount option(s) and continuing.");
262         /* Keep this first! */
263         if (on_errors != -1) {
264                 if (!on_errors) {
265                         ntfs_error(vol->sb, "Invalid errors option argument "
266                                         "or bug in options parser.");
267                         return false;
268                 }
269         }
270         if (nls_map) {
271                 if (vol->nls_map && vol->nls_map != nls_map) {
272                         ntfs_error(vol->sb, "Cannot change NLS character set "
273                                         "on remount.");
274                         return false;
275                 } /* else (!vol->nls_map) */
276                 ntfs_debug("Using NLS character set %s.", nls_map->charset);
277                 vol->nls_map = nls_map;
278         } else /* (!nls_map) */ {
279                 if (!vol->nls_map) {
280                         vol->nls_map = load_nls_default();
281                         if (!vol->nls_map) {
282                                 ntfs_error(vol->sb, "Failed to load default "
283                                                 "NLS character set.");
284                                 return false;
285                         }
286                         ntfs_debug("Using default NLS character set (%s).",
287                                         vol->nls_map->charset);
288                 }
289         }
290         if (mft_zone_multiplier != -1) {
291                 if (vol->mft_zone_multiplier && vol->mft_zone_multiplier !=
292                                 mft_zone_multiplier) {
293                         ntfs_error(vol->sb, "Cannot change mft_zone_multiplier "
294                                         "on remount.");
295                         return false;
296                 }
297                 if (mft_zone_multiplier < 1 || mft_zone_multiplier > 4) {
298                         ntfs_error(vol->sb, "Invalid mft_zone_multiplier. "
299                                         "Using default value, i.e. 1.");
300                         mft_zone_multiplier = 1;
301                 }
302                 vol->mft_zone_multiplier = mft_zone_multiplier;
303         }
304         if (!vol->mft_zone_multiplier)
305                 vol->mft_zone_multiplier = 1;
306         if (on_errors != -1)
307                 vol->on_errors = on_errors;
308         if (!vol->on_errors || vol->on_errors == ON_ERRORS_RECOVER)
309                 vol->on_errors |= ON_ERRORS_CONTINUE;
310         if (uid_valid(uid))
311                 vol->uid = uid;
312         if (gid_valid(gid))
313                 vol->gid = gid;
314         if (fmask != (umode_t)-1)
315                 vol->fmask = fmask;
316         if (dmask != (umode_t)-1)
317                 vol->dmask = dmask;
318         if (show_sys_files != -1) {
319                 if (show_sys_files)
320                         NVolSetShowSystemFiles(vol);
321                 else
322                         NVolClearShowSystemFiles(vol);
323         }
324         if (case_sensitive != -1) {
325                 if (case_sensitive)
326                         NVolSetCaseSensitive(vol);
327                 else
328                         NVolClearCaseSensitive(vol);
329         }
330         if (disable_sparse != -1) {
331                 if (disable_sparse)
332                         NVolClearSparseEnabled(vol);
333                 else {
334                         if (!NVolSparseEnabled(vol) &&
335                                         vol->major_ver && vol->major_ver < 3)
336                                 ntfs_warning(vol->sb, "Not enabling sparse "
337                                                 "support due to NTFS volume "
338                                                 "version %i.%i (need at least "
339                                                 "version 3.0).", vol->major_ver,
340                                                 vol->minor_ver);
341                         else
342                                 NVolSetSparseEnabled(vol);
343                 }
344         }
345         return true;
346 needs_arg:
347         ntfs_error(vol->sb, "The %s option requires an argument.", p);
348         return false;
349 needs_bool:
350         ntfs_error(vol->sb, "The %s option requires a boolean argument.", p);
351         return false;
352 needs_val:
353         ntfs_error(vol->sb, "Invalid %s option argument: %s", p, ov);
354         return false;
355 }
356 
357 #ifdef NTFS_RW
358 
359 /**
360  * ntfs_write_volume_flags - write new flags to the volume information flags
361  * @vol:        ntfs volume on which to modify the flags
362  * @flags:      new flags value for the volume information flags
363  *
364  * Internal function.  You probably want to use ntfs_{set,clear}_volume_flags()
365  * instead (see below).
366  *
367  * Replace the volume information flags on the volume @vol with the value
368  * supplied in @flags.  Note, this overwrites the volume information flags, so
369  * make sure to combine the flags you want to modify with the old flags and use
370  * the result when calling ntfs_write_volume_flags().
371  *
372  * Return 0 on success and -errno on error.
373  */
374 static int ntfs_write_volume_flags(ntfs_volume *vol, const VOLUME_FLAGS flags)
375 {
376         ntfs_inode *ni = NTFS_I(vol->vol_ino);
377         MFT_RECORD *m;
378         VOLUME_INFORMATION *vi;
379         ntfs_attr_search_ctx *ctx;
380         int err;
381 
382         ntfs_debug("Entering, old flags = 0x%x, new flags = 0x%x.",
383                         le16_to_cpu(vol->vol_flags), le16_to_cpu(flags));
384         if (vol->vol_flags == flags)
385                 goto done;
386         BUG_ON(!ni);
387         m = map_mft_record(ni);
388         if (IS_ERR(m)) {
389                 err = PTR_ERR(m);
390                 goto err_out;
391         }
392         ctx = ntfs_attr_get_search_ctx(ni, m);
393         if (!ctx) {
394                 err = -ENOMEM;
395                 goto put_unm_err_out;
396         }
397         err = ntfs_attr_lookup(AT_VOLUME_INFORMATION, NULL, 0, 0, 0, NULL, 0,
398                         ctx);
399         if (err)
400                 goto put_unm_err_out;
401         vi = (VOLUME_INFORMATION*)((u8*)ctx->attr +
402                         le16_to_cpu(ctx->attr->data.resident.value_offset));
403         vol->vol_flags = vi->flags = flags;
404         flush_dcache_mft_record_page(ctx->ntfs_ino);
405         mark_mft_record_dirty(ctx->ntfs_ino);
406         ntfs_attr_put_search_ctx(ctx);
407         unmap_mft_record(ni);
408 done:
409         ntfs_debug("Done.");
410         return 0;
411 put_unm_err_out:
412         if (ctx)
413                 ntfs_attr_put_search_ctx(ctx);
414         unmap_mft_record(ni);
415 err_out:
416         ntfs_error(vol->sb, "Failed with error code %i.", -err);
417         return err;
418 }
419 
420 /**
421  * ntfs_set_volume_flags - set bits in the volume information flags
422  * @vol:        ntfs volume on which to modify the flags
423  * @flags:      flags to set on the volume
424  *
425  * Set the bits in @flags in the volume information flags on the volume @vol.
426  *
427  * Return 0 on success and -errno on error.
428  */
429 static inline int ntfs_set_volume_flags(ntfs_volume *vol, VOLUME_FLAGS flags)
430 {
431         flags &= VOLUME_FLAGS_MASK;
432         return ntfs_write_volume_flags(vol, vol->vol_flags | flags);
433 }
434 
435 /**
436  * ntfs_clear_volume_flags - clear bits in the volume information flags
437  * @vol:        ntfs volume on which to modify the flags
438  * @flags:      flags to clear on the volume
439  *
440  * Clear the bits in @flags in the volume information flags on the volume @vol.
441  *
442  * Return 0 on success and -errno on error.
443  */
444 static inline int ntfs_clear_volume_flags(ntfs_volume *vol, VOLUME_FLAGS flags)
445 {
446         flags &= VOLUME_FLAGS_MASK;
447         flags = vol->vol_flags & cpu_to_le16(~le16_to_cpu(flags));
448         return ntfs_write_volume_flags(vol, flags);
449 }
450 
451 #endif /* NTFS_RW */
452 
453 /**
454  * ntfs_remount - change the mount options of a mounted ntfs filesystem
455  * @sb:         superblock of mounted ntfs filesystem
456  * @flags:      remount flags
457  * @opt:        remount options string
458  *
459  * Change the mount options of an already mounted ntfs filesystem.
460  *
461  * NOTE:  The VFS sets the @sb->s_flags remount flags to @flags after
462  * ntfs_remount() returns successfully (i.e. returns 0).  Otherwise,
463  * @sb->s_flags are not changed.
464  */
465 static int ntfs_remount(struct super_block *sb, int *flags, char *opt)
466 {
467         ntfs_volume *vol = NTFS_SB(sb);
468 
469         ntfs_debug("Entering with remount options string: %s", opt);
470 
471 #ifndef NTFS_RW
472         /* For read-only compiled driver, enforce read-only flag. */
473         *flags |= MS_RDONLY;
474 #else /* NTFS_RW */
475         /*
476          * For the read-write compiled driver, if we are remounting read-write,
477          * make sure there are no volume errors and that no unsupported volume
478          * flags are set.  Also, empty the logfile journal as it would become
479          * stale as soon as something is written to the volume and mark the
480          * volume dirty so that chkdsk is run if the volume is not umounted
481          * cleanly.  Finally, mark the quotas out of date so Windows rescans
482          * the volume on boot and updates them.
483          *
484          * When remounting read-only, mark the volume clean if no volume errors
485          * have occurred.
486          */
487         if ((sb->s_flags & MS_RDONLY) && !(*flags & MS_RDONLY)) {
488                 static const char *es = ".  Cannot remount read-write.";
489 
490                 /* Remounting read-write. */
491                 if (NVolErrors(vol)) {
492                         ntfs_error(sb, "Volume has errors and is read-only%s",
493                                         es);
494                         return -EROFS;
495                 }
496                 if (vol->vol_flags & VOLUME_IS_DIRTY) {
497                         ntfs_error(sb, "Volume is dirty and read-only%s", es);
498                         return -EROFS;
499                 }
500                 if (vol->vol_flags & VOLUME_MODIFIED_BY_CHKDSK) {
501                         ntfs_error(sb, "Volume has been modified by chkdsk "
502                                         "and is read-only%s", es);
503                         return -EROFS;
504                 }
505                 if (vol->vol_flags & VOLUME_MUST_MOUNT_RO_MASK) {
506                         ntfs_error(sb, "Volume has unsupported flags set "
507                                         "(0x%x) and is read-only%s",
508                                         (unsigned)le16_to_cpu(vol->vol_flags),
509                                         es);
510                         return -EROFS;
511                 }
512                 if (ntfs_set_volume_flags(vol, VOLUME_IS_DIRTY)) {
513                         ntfs_error(sb, "Failed to set dirty bit in volume "
514                                         "information flags%s", es);
515                         return -EROFS;
516                 }
517 #if 0
518                 // TODO: Enable this code once we start modifying anything that
519                 //       is different between NTFS 1.2 and 3.x...
520                 /* Set NT4 compatibility flag on newer NTFS version volumes. */
521                 if ((vol->major_ver > 1)) {
522                         if (ntfs_set_volume_flags(vol, VOLUME_MOUNTED_ON_NT4)) {
523                                 ntfs_error(sb, "Failed to set NT4 "
524                                                 "compatibility flag%s", es);
525                                 NVolSetErrors(vol);
526                                 return -EROFS;
527                         }
528                 }
529 #endif
530                 if (!ntfs_empty_logfile(vol->logfile_ino)) {
531                         ntfs_error(sb, "Failed to empty journal $LogFile%s",
532                                         es);
533                         NVolSetErrors(vol);
534                         return -EROFS;
535                 }
536                 if (!ntfs_mark_quotas_out_of_date(vol)) {
537                         ntfs_error(sb, "Failed to mark quotas out of date%s",
538                                         es);
539                         NVolSetErrors(vol);
540                         return -EROFS;
541                 }
542                 if (!ntfs_stamp_usnjrnl(vol)) {
543                         ntfs_error(sb, "Failed to stamp transation log "
544                                         "($UsnJrnl)%s", es);
545                         NVolSetErrors(vol);
546                         return -EROFS;
547                 }
548         } else if (!(sb->s_flags & MS_RDONLY) && (*flags & MS_RDONLY)) {
549                 /* Remounting read-only. */
550                 if (!NVolErrors(vol)) {
551                         if (ntfs_clear_volume_flags(vol, VOLUME_IS_DIRTY))
552                                 ntfs_warning(sb, "Failed to clear dirty bit "
553                                                 "in volume information "
554                                                 "flags.  Run chkdsk.");
555                 }
556         }
557 #endif /* NTFS_RW */
558 
559         // TODO: Deal with *flags.
560 
561         if (!parse_options(vol, opt))
562                 return -EINVAL;
563 
564         ntfs_debug("Done.");
565         return 0;
566 }
567 
568 /**
569  * is_boot_sector_ntfs - check whether a boot sector is a valid NTFS boot sector
570  * @sb:         Super block of the device to which @b belongs.
571  * @b:          Boot sector of device @sb to check.
572  * @silent:     If 'true', all output will be silenced.
573  *
574  * is_boot_sector_ntfs() checks whether the boot sector @b is a valid NTFS boot
575  * sector. Returns 'true' if it is valid and 'false' if not.
576  *
577  * @sb is only needed for warning/error output, i.e. it can be NULL when silent
578  * is 'true'.
579  */
580 static bool is_boot_sector_ntfs(const struct super_block *sb,
581                 const NTFS_BOOT_SECTOR *b, const bool silent)
582 {
583         /*
584          * Check that checksum == sum of u32 values from b to the checksum
585          * field.  If checksum is zero, no checking is done.  We will work when
586          * the checksum test fails, since some utilities update the boot sector
587          * ignoring the checksum which leaves the checksum out-of-date.  We
588          * report a warning if this is the case.
589          */
590         if ((void*)b < (void*)&b->checksum && b->checksum && !silent) {
591                 le32 *u;
592                 u32 i;
593 
594                 for (i = 0, u = (le32*)b; u < (le32*)(&b->checksum); ++u)
595                         i += le32_to_cpup(u);
596                 if (le32_to_cpu(b->checksum) != i)
597                         ntfs_warning(sb, "Invalid boot sector checksum.");
598         }
599         /* Check OEMidentifier is "NTFS    " */
600         if (b->oem_id != magicNTFS)
601                 goto not_ntfs;
602         /* Check bytes per sector value is between 256 and 4096. */
603         if (le16_to_cpu(b->bpb.bytes_per_sector) < 0x100 ||
604                         le16_to_cpu(b->bpb.bytes_per_sector) > 0x1000)
605                 goto not_ntfs;
606         /* Check sectors per cluster value is valid. */
607         switch (b->bpb.sectors_per_cluster) {
608         case 1: case 2: case 4: case 8: case 16: case 32: case 64: case 128:
609                 break;
610         default:
611                 goto not_ntfs;
612         }
613         /* Check the cluster size is not above the maximum (64kiB). */
614         if ((u32)le16_to_cpu(b->bpb.bytes_per_sector) *
615                         b->bpb.sectors_per_cluster > NTFS_MAX_CLUSTER_SIZE)
616                 goto not_ntfs;
617         /* Check reserved/unused fields are really zero. */
618         if (le16_to_cpu(b->bpb.reserved_sectors) ||
619                         le16_to_cpu(b->bpb.root_entries) ||
620                         le16_to_cpu(b->bpb.sectors) ||
621                         le16_to_cpu(b->bpb.sectors_per_fat) ||
622                         le32_to_cpu(b->bpb.large_sectors) || b->bpb.fats)
623                 goto not_ntfs;
624         /* Check clusters per file mft record value is valid. */
625         if ((u8)b->clusters_per_mft_record < 0xe1 ||
626                         (u8)b->clusters_per_mft_record > 0xf7)
627                 switch (b->clusters_per_mft_record) {
628                 case 1: case 2: case 4: case 8: case 16: case 32: case 64:
629                         break;
630                 default:
631                         goto not_ntfs;
632                 }
633         /* Check clusters per index block value is valid. */
634         if ((u8)b->clusters_per_index_record < 0xe1 ||
635                         (u8)b->clusters_per_index_record > 0xf7)
636                 switch (b->clusters_per_index_record) {
637                 case 1: case 2: case 4: case 8: case 16: case 32: case 64:
638                         break;
639                 default:
640                         goto not_ntfs;
641                 }
642         /*
643          * Check for valid end of sector marker. We will work without it, but
644          * many BIOSes will refuse to boot from a bootsector if the magic is
645          * incorrect, so we emit a warning.
646          */
647         if (!silent && b->end_of_sector_marker != cpu_to_le16(0xaa55))
648                 ntfs_warning(sb, "Invalid end of sector marker.");
649         return true;
650 not_ntfs:
651         return false;
652 }
653 
654 /**
655  * read_ntfs_boot_sector - read the NTFS boot sector of a device
656  * @sb:         super block of device to read the boot sector from
657  * @silent:     if true, suppress all output
658  *
659  * Reads the boot sector from the device and validates it. If that fails, tries
660  * to read the backup boot sector, first from the end of the device a-la NT4 and
661  * later and then from the middle of the device a-la NT3.51 and before.
662  *
663  * If a valid boot sector is found but it is not the primary boot sector, we
664  * repair the primary boot sector silently (unless the device is read-only or
665  * the primary boot sector is not accessible).
666  *
667  * NOTE: To call this function, @sb must have the fields s_dev, the ntfs super
668  * block (u.ntfs_sb), nr_blocks and the device flags (s_flags) initialized
669  * to their respective values.
670  *
671  * Return the unlocked buffer head containing the boot sector or NULL on error.
672  */
673 static struct buffer_head *read_ntfs_boot_sector(struct super_block *sb,
674                 const int silent)
675 {
676         const char *read_err_str = "Unable to read %s boot sector.";
677         struct buffer_head *bh_primary, *bh_backup;
678         sector_t nr_blocks = NTFS_SB(sb)->nr_blocks;
679 
680         /* Try to read primary boot sector. */
681         if ((bh_primary = sb_bread(sb, 0))) {
682                 if (is_boot_sector_ntfs(sb, (NTFS_BOOT_SECTOR*)
683                                 bh_primary->b_data, silent))
684                         return bh_primary;
685                 if (!silent)
686                         ntfs_error(sb, "Primary boot sector is invalid.");
687         } else if (!silent)
688                 ntfs_error(sb, read_err_str, "primary");
689         if (!(NTFS_SB(sb)->on_errors & ON_ERRORS_RECOVER)) {
690                 if (bh_primary)
691                         brelse(bh_primary);
692                 if (!silent)
693                         ntfs_error(sb, "Mount option errors=recover not used. "
694                                         "Aborting without trying to recover.");
695                 return NULL;
696         }
697         /* Try to read NT4+ backup boot sector. */
698         if ((bh_backup = sb_bread(sb, nr_blocks - 1))) {
699                 if (is_boot_sector_ntfs(sb, (NTFS_BOOT_SECTOR*)
700                                 bh_backup->b_data, silent))
701                         goto hotfix_primary_boot_sector;
702                 brelse(bh_backup);
703         } else if (!silent)
704                 ntfs_error(sb, read_err_str, "backup");
705         /* Try to read NT3.51- backup boot sector. */
706         if ((bh_backup = sb_bread(sb, nr_blocks >> 1))) {
707                 if (is_boot_sector_ntfs(sb, (NTFS_BOOT_SECTOR*)
708                                 bh_backup->b_data, silent))
709                         goto hotfix_primary_boot_sector;
710                 if (!silent)
711                         ntfs_error(sb, "Could not find a valid backup boot "
712                                         "sector.");
713                 brelse(bh_backup);
714         } else if (!silent)
715                 ntfs_error(sb, read_err_str, "backup");
716         /* We failed. Cleanup and return. */
717         if (bh_primary)
718                 brelse(bh_primary);
719         return NULL;
720 hotfix_primary_boot_sector:
721         if (bh_primary) {
722                 /*
723                  * If we managed to read sector zero and the volume is not
724                  * read-only, copy the found, valid backup boot sector to the
725                  * primary boot sector.  Note we only copy the actual boot
726                  * sector structure, not the actual whole device sector as that
727                  * may be bigger and would potentially damage the $Boot system
728                  * file (FIXME: Would be nice to know if the backup boot sector
729                  * on a large sector device contains the whole boot loader or
730                  * just the first 512 bytes).
731                  */
732                 if (!(sb->s_flags & MS_RDONLY)) {
733                         ntfs_warning(sb, "Hot-fix: Recovering invalid primary "
734                                         "boot sector from backup copy.");
735                         memcpy(bh_primary->b_data, bh_backup->b_data,
736                                         NTFS_BLOCK_SIZE);
737                         mark_buffer_dirty(bh_primary);
738                         sync_dirty_buffer(bh_primary);
739                         if (buffer_uptodate(bh_primary)) {
740                                 brelse(bh_backup);
741                                 return bh_primary;
742                         }
743                         ntfs_error(sb, "Hot-fix: Device write error while "
744                                         "recovering primary boot sector.");
745                 } else {
746                         ntfs_warning(sb, "Hot-fix: Recovery of primary boot "
747                                         "sector failed: Read-only mount.");
748                 }
749                 brelse(bh_primary);
750         }
751         ntfs_warning(sb, "Using backup boot sector.");
752         return bh_backup;
753 }
754 
755 /**
756  * parse_ntfs_boot_sector - parse the boot sector and store the data in @vol
757  * @vol:        volume structure to initialise with data from boot sector
758  * @b:          boot sector to parse
759  *
760  * Parse the ntfs boot sector @b and store all imporant information therein in
761  * the ntfs super block @vol.  Return 'true' on success and 'false' on error.
762  */
763 static bool parse_ntfs_boot_sector(ntfs_volume *vol, const NTFS_BOOT_SECTOR *b)
764 {
765         unsigned int sectors_per_cluster_bits, nr_hidden_sects;
766         int clusters_per_mft_record, clusters_per_index_record;
767         s64 ll;
768 
769         vol->sector_size = le16_to_cpu(b->bpb.bytes_per_sector);
770         vol->sector_size_bits = ffs(vol->sector_size) - 1;
771         ntfs_debug("vol->sector_size = %i (0x%x)", vol->sector_size,
772                         vol->sector_size);
773         ntfs_debug("vol->sector_size_bits = %i (0x%x)", vol->sector_size_bits,
774                         vol->sector_size_bits);
775         if (vol->sector_size < vol->sb->s_blocksize) {
776                 ntfs_error(vol->sb, "Sector size (%i) is smaller than the "
777                                 "device block size (%lu).  This is not "
778                                 "supported.  Sorry.", vol->sector_size,
779                                 vol->sb->s_blocksize);
780                 return false;
781         }
782         ntfs_debug("sectors_per_cluster = 0x%x", b->bpb.sectors_per_cluster);
783         sectors_per_cluster_bits = ffs(b->bpb.sectors_per_cluster) - 1;
784         ntfs_debug("sectors_per_cluster_bits = 0x%x",
785                         sectors_per_cluster_bits);
786         nr_hidden_sects = le32_to_cpu(b->bpb.hidden_sectors);
787         ntfs_debug("number of hidden sectors = 0x%x", nr_hidden_sects);
788         vol->cluster_size = vol->sector_size << sectors_per_cluster_bits;
789         vol->cluster_size_mask = vol->cluster_size - 1;
790         vol->cluster_size_bits = ffs(vol->cluster_size) - 1;
791         ntfs_debug("vol->cluster_size = %i (0x%x)", vol->cluster_size,
792                         vol->cluster_size);
793         ntfs_debug("vol->cluster_size_mask = 0x%x", vol->cluster_size_mask);
794         ntfs_debug("vol->cluster_size_bits = %i", vol->cluster_size_bits);
795         if (vol->cluster_size < vol->sector_size) {
796                 ntfs_error(vol->sb, "Cluster size (%i) is smaller than the "
797                                 "sector size (%i).  This is not supported.  "
798                                 "Sorry.", vol->cluster_size, vol->sector_size);
799                 return false;
800         }
801         clusters_per_mft_record = b->clusters_per_mft_record;
802         ntfs_debug("clusters_per_mft_record = %i (0x%x)",
803                         clusters_per_mft_record, clusters_per_mft_record);
804         if (clusters_per_mft_record > 0)
805                 vol->mft_record_size = vol->cluster_size <<
806                                 (ffs(clusters_per_mft_record) - 1);
807         else
808                 /*
809                  * When mft_record_size < cluster_size, clusters_per_mft_record
810                  * = -log2(mft_record_size) bytes. mft_record_size normaly is
811                  * 1024 bytes, which is encoded as 0xF6 (-10 in decimal).
812                  */
813                 vol->mft_record_size = 1 << -clusters_per_mft_record;
814         vol->mft_record_size_mask = vol->mft_record_size - 1;
815         vol->mft_record_size_bits = ffs(vol->mft_record_size) - 1;
816         ntfs_debug("vol->mft_record_size = %i (0x%x)", vol->mft_record_size,
817                         vol->mft_record_size);
818         ntfs_debug("vol->mft_record_size_mask = 0x%x",
819                         vol->mft_record_size_mask);
820         ntfs_debug("vol->mft_record_size_bits = %i (0x%x)",
821                         vol->mft_record_size_bits, vol->mft_record_size_bits);
822         /*
823          * We cannot support mft record sizes above the PAGE_CACHE_SIZE since
824          * we store $MFT/$DATA, the table of mft records in the page cache.
825          */
826         if (vol->mft_record_size > PAGE_CACHE_SIZE) {
827                 ntfs_error(vol->sb, "Mft record size (%i) exceeds the "
828                                 "PAGE_CACHE_SIZE on your system (%lu).  "
829                                 "This is not supported.  Sorry.",
830                                 vol->mft_record_size, PAGE_CACHE_SIZE);
831                 return false;
832         }
833         /* We cannot support mft record sizes below the sector size. */
834         if (vol->mft_record_size < vol->sector_size) {
835                 ntfs_error(vol->sb, "Mft record size (%i) is smaller than the "
836                                 "sector size (%i).  This is not supported.  "
837                                 "Sorry.", vol->mft_record_size,
838                                 vol->sector_size);
839                 return false;
840         }
841         clusters_per_index_record = b->clusters_per_index_record;
842         ntfs_debug("clusters_per_index_record = %i (0x%x)",
843                         clusters_per_index_record, clusters_per_index_record);
844         if (clusters_per_index_record > 0)
845                 vol->index_record_size = vol->cluster_size <<
846                                 (ffs(clusters_per_index_record) - 1);
847         else
848                 /*
849                  * When index_record_size < cluster_size,
850                  * clusters_per_index_record = -log2(index_record_size) bytes.
851                  * index_record_size normaly equals 4096 bytes, which is
852                  * encoded as 0xF4 (-12 in decimal).
853                  */
854                 vol->index_record_size = 1 << -clusters_per_index_record;
855         vol->index_record_size_mask = vol->index_record_size - 1;
856         vol->index_record_size_bits = ffs(vol->index_record_size) - 1;
857         ntfs_debug("vol->index_record_size = %i (0x%x)",
858                         vol->index_record_size, vol->index_record_size);
859         ntfs_debug("vol->index_record_size_mask = 0x%x",
860                         vol->index_record_size_mask);
861         ntfs_debug("vol->index_record_size_bits = %i (0x%x)",
862                         vol->index_record_size_bits,
863                         vol->index_record_size_bits);
864         /* We cannot support index record sizes below the sector size. */
865         if (vol->index_record_size < vol->sector_size) {
866                 ntfs_error(vol->sb, "Index record size (%i) is smaller than "
867                                 "the sector size (%i).  This is not "
868                                 "supported.  Sorry.", vol->index_record_size,
869                                 vol->sector_size);
870                 return false;
871         }
872         /*
873          * Get the size of the volume in clusters and check for 64-bit-ness.
874          * Windows currently only uses 32 bits to save the clusters so we do
875          * the same as it is much faster on 32-bit CPUs.
876          */
877         ll = sle64_to_cpu(b->number_of_sectors) >> sectors_per_cluster_bits;
878         if ((u64)ll >= 1ULL << 32) {
879                 ntfs_error(vol->sb, "Cannot handle 64-bit clusters.  Sorry.");
880                 return false;
881         }
882         vol->nr_clusters = ll;
883         ntfs_debug("vol->nr_clusters = 0x%llx", (long long)vol->nr_clusters);
884         /*
885          * On an architecture where unsigned long is 32-bits, we restrict the
886          * volume size to 2TiB (2^41). On a 64-bit architecture, the compiler
887          * will hopefully optimize the whole check away.
888          */
889         if (sizeof(unsigned long) < 8) {
890                 if ((ll << vol->cluster_size_bits) >= (1ULL << 41)) {
891                         ntfs_error(vol->sb, "Volume size (%lluTiB) is too "
892                                         "large for this architecture.  "
893                                         "Maximum supported is 2TiB.  Sorry.",
894                                         (unsigned long long)ll >> (40 -
895                                         vol->cluster_size_bits));
896                         return false;
897                 }
898         }
899         ll = sle64_to_cpu(b->mft_lcn);
900         if (ll >= vol->nr_clusters) {
901                 ntfs_error(vol->sb, "MFT LCN (%lli, 0x%llx) is beyond end of "
902                                 "volume.  Weird.", (unsigned long long)ll,
903                                 (unsigned long long)ll);
904                 return false;
905         }
906         vol->mft_lcn = ll;
907         ntfs_debug("vol->mft_lcn = 0x%llx", (long long)vol->mft_lcn);
908         ll = sle64_to_cpu(b->mftmirr_lcn);
909         if (ll >= vol->nr_clusters) {
910                 ntfs_error(vol->sb, "MFTMirr LCN (%lli, 0x%llx) is beyond end "
911                                 "of volume.  Weird.", (unsigned long long)ll,
912                                 (unsigned long long)ll);
913                 return false;
914         }
915         vol->mftmirr_lcn = ll;
916         ntfs_debug("vol->mftmirr_lcn = 0x%llx", (long long)vol->mftmirr_lcn);
917 #ifdef NTFS_RW
918         /*
919          * Work out the size of the mft mirror in number of mft records. If the
920          * cluster size is less than or equal to the size taken by four mft
921          * records, the mft mirror stores the first four mft records. If the
922          * cluster size is bigger than the size taken by four mft records, the
923          * mft mirror contains as many mft records as will fit into one
924          * cluster.
925          */
926         if (vol->cluster_size <= (4 << vol->mft_record_size_bits))
927                 vol->mftmirr_size = 4;
928         else
929                 vol->mftmirr_size = vol->cluster_size >>
930                                 vol->mft_record_size_bits;
931         ntfs_debug("vol->mftmirr_size = %i", vol->mftmirr_size);
932 #endif /* NTFS_RW */
933         vol->serial_no = le64_to_cpu(b->volume_serial_number);
934         ntfs_debug("vol->serial_no = 0x%llx",
935                         (unsigned long long)vol->serial_no);
936         return true;
937 }
938 
939 /**
940  * ntfs_setup_allocators - initialize the cluster and mft allocators
941  * @vol:        volume structure for which to setup the allocators
942  *
943  * Setup the cluster (lcn) and mft allocators to the starting values.
944  */
945 static void ntfs_setup_allocators(ntfs_volume *vol)
946 {
947 #ifdef NTFS_RW
948         LCN mft_zone_size, mft_lcn;
949 #endif /* NTFS_RW */
950 
951         ntfs_debug("vol->mft_zone_multiplier = 0x%x",
952                         vol->mft_zone_multiplier);
953 #ifdef NTFS_RW
954         /* Determine the size of the MFT zone. */
955         mft_zone_size = vol->nr_clusters;
956         switch (vol->mft_zone_multiplier) {  /* % of volume size in clusters */
957         case 4:
958                 mft_zone_size >>= 1;                    /* 50%   */
959                 break;
960         case 3:
961                 mft_zone_size = (mft_zone_size +
962                                 (mft_zone_size >> 1)) >> 2;     /* 37.5% */
963                 break;
964         case 2:
965                 mft_zone_size >>= 2;                    /* 25%   */
966                 break;
967         /* case 1: */
968         default:
969                 mft_zone_size >>= 3;                    /* 12.5% */
970                 break;
971         }
972         /* Setup the mft zone. */
973         vol->mft_zone_start = vol->mft_zone_pos = vol->mft_lcn;
974         ntfs_debug("vol->mft_zone_pos = 0x%llx",
975                         (unsigned long long)vol->mft_zone_pos);
976         /*
977          * Calculate the mft_lcn for an unmodified NTFS volume (see mkntfs
978          * source) and if the actual mft_lcn is in the expected place or even
979          * further to the front of the volume, extend the mft_zone to cover the
980          * beginning of the volume as well.  This is in order to protect the
981          * area reserved for the mft bitmap as well within the mft_zone itself.
982          * On non-standard volumes we do not protect it as the overhead would
983          * be higher than the speed increase we would get by doing it.
984          */
985         mft_lcn = (8192 + 2 * vol->cluster_size - 1) / vol->cluster_size;
986         if (mft_lcn * vol->cluster_size < 16 * 1024)
987                 mft_lcn = (16 * 1024 + vol->cluster_size - 1) /
988                                 vol->cluster_size;
989         if (vol->mft_zone_start <= mft_lcn)
990                 vol->mft_zone_start = 0;
991         ntfs_debug("vol->mft_zone_start = 0x%llx",
992                         (unsigned long long)vol->mft_zone_start);
993         /*
994          * Need to cap the mft zone on non-standard volumes so that it does
995          * not point outside the boundaries of the volume.  We do this by
996          * halving the zone size until we are inside the volume.
997          */
998         vol->mft_zone_end = vol->mft_lcn + mft_zone_size;
999         while (vol->mft_zone_end >= vol->nr_clusters) {
1000                 mft_zone_size >>= 1;
1001                 vol->mft_zone_end = vol->mft_lcn + mft_zone_size;
1002         }
1003         ntfs_debug("vol->mft_zone_end = 0x%llx",
1004                         (unsigned long long)vol->mft_zone_end);
1005         /*
1006          * Set the current position within each data zone to the start of the
1007          * respective zone.
1008          */
1009         vol->data1_zone_pos = vol->mft_zone_end;
1010         ntfs_debug("vol->data1_zone_pos = 0x%llx",
1011                         (unsigned long long)vol->data1_zone_pos);
1012         vol->data2_zone_pos = 0;
1013         ntfs_debug("vol->data2_zone_pos = 0x%llx",
1014                         (unsigned long long)vol->data2_zone_pos);
1015 
1016         /* Set the mft data allocation position to mft record 24. */
1017         vol->mft_data_pos = 24;
1018         ntfs_debug("vol->mft_data_pos = 0x%llx",
1019                         (unsigned long long)vol->mft_data_pos);
1020 #endif /* NTFS_RW */
1021 }
1022 
1023 #ifdef NTFS_RW
1024 
1025 /**
1026  * load_and_init_mft_mirror - load and setup the mft mirror inode for a volume
1027  * @vol:        ntfs super block describing device whose mft mirror to load
1028  *
1029  * Return 'true' on success or 'false' on error.
1030  */
1031 static bool load_and_init_mft_mirror(ntfs_volume *vol)
1032 {
1033         struct inode *tmp_ino;
1034         ntfs_inode *tmp_ni;
1035 
1036         ntfs_debug("Entering.");
1037         /* Get mft mirror inode. */
1038         tmp_ino = ntfs_iget(vol->sb, FILE_MFTMirr);
1039         if (IS_ERR(tmp_ino) || is_bad_inode(tmp_ino)) {
1040                 if (!IS_ERR(tmp_ino))
1041                         iput(tmp_ino);
1042                 /* Caller will display error message. */
1043                 return false;
1044         }
1045         /*
1046          * Re-initialize some specifics about $MFTMirr's inode as
1047          * ntfs_read_inode() will have set up the default ones.
1048          */
1049         /* Set uid and gid to root. */
1050         tmp_ino->i_uid = GLOBAL_ROOT_UID;
1051         tmp_ino->i_gid = GLOBAL_ROOT_GID;
1052         /* Regular file.  No access for anyone. */
1053         tmp_ino->i_mode = S_IFREG;
1054         /* No VFS initiated operations allowed for $MFTMirr. */
1055         tmp_ino->i_op = &ntfs_empty_inode_ops;
1056         tmp_ino->i_fop = &ntfs_empty_file_ops;
1057         /* Put in our special address space operations. */
1058         tmp_ino->i_mapping->a_ops = &ntfs_mst_aops;
1059         tmp_ni = NTFS_I(tmp_ino);
1060         /* The $MFTMirr, like the $MFT is multi sector transfer protected. */
1061         NInoSetMstProtected(tmp_ni);
1062         NInoSetSparseDisabled(tmp_ni);
1063         /*
1064          * Set up our little cheat allowing us to reuse the async read io
1065          * completion handler for directories.
1066          */
1067         tmp_ni->itype.index.block_size = vol->mft_record_size;
1068         tmp_ni->itype.index.block_size_bits = vol->mft_record_size_bits;
1069         vol->mftmirr_ino = tmp_ino;
1070         ntfs_debug("Done.");
1071         return true;
1072 }
1073 
1074 /**
1075  * check_mft_mirror - compare contents of the mft mirror with the mft
1076  * @vol:        ntfs super block describing device whose mft mirror to check
1077  *
1078  * Return 'true' on success or 'false' on error.
1079  *
1080  * Note, this function also results in the mft mirror runlist being completely
1081  * mapped into memory.  The mft mirror write code requires this and will BUG()
1082  * should it find an unmapped runlist element.
1083  */
1084 static bool check_mft_mirror(ntfs_volume *vol)
1085 {
1086         struct super_block *sb = vol->sb;
1087         ntfs_inode *mirr_ni;
1088         struct page *mft_page, *mirr_page;
1089         u8 *kmft, *kmirr;
1090         runlist_element *rl, rl2[2];
1091         pgoff_t index;
1092         int mrecs_per_page, i;
1093 
1094         ntfs_debug("Entering.");
1095         /* Compare contents of $MFT and $MFTMirr. */
1096         mrecs_per_page = PAGE_CACHE_SIZE / vol->mft_record_size;
1097         BUG_ON(!mrecs_per_page);
1098         BUG_ON(!vol->mftmirr_size);
1099         mft_page = mirr_page = NULL;
1100         kmft = kmirr = NULL;
1101         index = i = 0;
1102         do {
1103                 u32 bytes;
1104 
1105                 /* Switch pages if necessary. */
1106                 if (!(i % mrecs_per_page)) {
1107                         if (index) {
1108                                 ntfs_unmap_page(mft_page);
1109                                 ntfs_unmap_page(mirr_page);
1110                         }
1111                         /* Get the $MFT page. */
1112                         mft_page = ntfs_map_page(vol->mft_ino->i_mapping,
1113                                         index);
1114                         if (IS_ERR(mft_page)) {
1115                                 ntfs_error(sb, "Failed to read $MFT.");
1116                                 return false;
1117                         }
1118                         kmft = page_address(mft_page);
1119                         /* Get the $MFTMirr page. */
1120                         mirr_page = ntfs_map_page(vol->mftmirr_ino->i_mapping,
1121                                         index);
1122                         if (IS_ERR(mirr_page)) {
1123                                 ntfs_error(sb, "Failed to read $MFTMirr.");
1124                                 goto mft_unmap_out;
1125                         }
1126                         kmirr = page_address(mirr_page);
1127                         ++index;
1128                 }
1129                 /* Do not check the record if it is not in use. */
1130                 if (((MFT_RECORD*)kmft)->flags & MFT_RECORD_IN_USE) {
1131                         /* Make sure the record is ok. */
1132                         if (ntfs_is_baad_recordp((le32*)kmft)) {
1133                                 ntfs_error(sb, "Incomplete multi sector "
1134                                                 "transfer detected in mft "
1135                                                 "record %i.", i);
1136 mm_unmap_out:
1137                                 ntfs_unmap_page(mirr_page);
1138 mft_unmap_out:
1139                                 ntfs_unmap_page(mft_page);
1140                                 return false;
1141                         }
1142                 }
1143                 /* Do not check the mirror record if it is not in use. */
1144                 if (((MFT_RECORD*)kmirr)->flags & MFT_RECORD_IN_USE) {
1145                         if (ntfs_is_baad_recordp((le32*)kmirr)) {
1146                                 ntfs_error(sb, "Incomplete multi sector "
1147                                                 "transfer detected in mft "
1148                                                 "mirror record %i.", i);
1149                                 goto mm_unmap_out;
1150                         }
1151                 }
1152                 /* Get the amount of data in the current record. */
1153                 bytes = le32_to_cpu(((MFT_RECORD*)kmft)->bytes_in_use);
1154                 if (bytes < sizeof(MFT_RECORD_OLD) ||
1155                                 bytes > vol->mft_record_size ||
1156                                 ntfs_is_baad_recordp((le32*)kmft)) {
1157                         bytes = le32_to_cpu(((MFT_RECORD*)kmirr)->bytes_in_use);
1158                         if (bytes < sizeof(MFT_RECORD_OLD) ||
1159                                         bytes > vol->mft_record_size ||
1160                                         ntfs_is_baad_recordp((le32*)kmirr))
1161                                 bytes = vol->mft_record_size;
1162                 }
1163                 /* Compare the two records. */
1164                 if (memcmp(kmft, kmirr, bytes)) {
1165                         ntfs_error(sb, "$MFT and $MFTMirr (record %i) do not "
1166                                         "match.  Run ntfsfix or chkdsk.", i);
1167                         goto mm_unmap_out;
1168                 }
1169                 kmft += vol->mft_record_size;
1170                 kmirr += vol->mft_record_size;
1171         } while (++i < vol->mftmirr_size);
1172         /* Release the last pages. */
1173         ntfs_unmap_page(mft_page);
1174         ntfs_unmap_page(mirr_page);
1175 
1176         /* Construct the mft mirror runlist by hand. */
1177         rl2[0].vcn = 0;
1178         rl2[0].lcn = vol->mftmirr_lcn;
1179         rl2[0].length = (vol->mftmirr_size * vol->mft_record_size +
1180                         vol->cluster_size - 1) / vol->cluster_size;
1181         rl2[1].vcn = rl2[0].length;
1182         rl2[1].lcn = LCN_ENOENT;
1183         rl2[1].length = 0;
1184         /*
1185          * Because we have just read all of the mft mirror, we know we have
1186          * mapped the full runlist for it.
1187          */
1188         mirr_ni = NTFS_I(vol->mftmirr_ino);
1189         down_read(&mirr_ni->runlist.lock);
1190         rl = mirr_ni->runlist.rl;
1191         /* Compare the two runlists.  They must be identical. */
1192         i = 0;
1193         do {
1194                 if (rl2[i].vcn != rl[i].vcn || rl2[i].lcn != rl[i].lcn ||
1195                                 rl2[i].length != rl[i].length) {
1196                         ntfs_error(sb, "$MFTMirr location mismatch.  "
1197                                         "Run chkdsk.");
1198                         up_read(&mirr_ni->runlist.lock);
1199                         return false;
1200                 }
1201         } while (rl2[i++].length);
1202         up_read(&mirr_ni->runlist.lock);
1203         ntfs_debug("Done.");
1204         return true;
1205 }
1206 
1207 /**
1208  * load_and_check_logfile - load and check the logfile inode for a volume
1209  * @vol:        ntfs super block describing device whose logfile to load
1210  *
1211  * Return 'true' on success or 'false' on error.
1212  */
1213 static bool load_and_check_logfile(ntfs_volume *vol,
1214                 RESTART_PAGE_HEADER **rp)
1215 {
1216         struct inode *tmp_ino;
1217 
1218         ntfs_debug("Entering.");
1219         tmp_ino = ntfs_iget(vol->sb, FILE_LogFile);
1220         if (IS_ERR(tmp_ino) || is_bad_inode(tmp_ino)) {
1221                 if (!IS_ERR(tmp_ino))
1222                         iput(tmp_ino);
1223                 /* Caller will display error message. */
1224                 return false;
1225         }
1226         if (!ntfs_check_logfile(tmp_ino, rp)) {
1227                 iput(tmp_ino);
1228                 /* ntfs_check_logfile() will have displayed error output. */
1229                 return false;
1230         }
1231         NInoSetSparseDisabled(NTFS_I(tmp_ino));
1232         vol->logfile_ino = tmp_ino;
1233         ntfs_debug("Done.");
1234         return true;
1235 }
1236 
1237 #define NTFS_HIBERFIL_HEADER_SIZE       4096
1238 
1239 /**
1240  * check_windows_hibernation_status - check if Windows is suspended on a volume
1241  * @vol:        ntfs super block of device to check
1242  *
1243  * Check if Windows is hibernated on the ntfs volume @vol.  This is done by
1244  * looking for the file hiberfil.sys in the root directory of the volume.  If
1245  * the file is not present Windows is definitely not suspended.
1246  *
1247  * If hiberfil.sys exists and is less than 4kiB in size it means Windows is
1248  * definitely suspended (this volume is not the system volume).  Caveat:  on a
1249  * system with many volumes it is possible that the < 4kiB check is bogus but
1250  * for now this should do fine.
1251  *
1252  * If hiberfil.sys exists and is larger than 4kiB in size, we need to read the
1253  * hiberfil header (which is the first 4kiB).  If this begins with "hibr",
1254  * Windows is definitely suspended.  If it is completely full of zeroes,
1255  * Windows is definitely not hibernated.  Any other case is treated as if
1256  * Windows is suspended.  This caters for the above mentioned caveat of a
1257  * system with many volumes where no "hibr" magic would be present and there is
1258  * no zero header.
1259  *
1260  * Return 0 if Windows is not hibernated on the volume, >0 if Windows is
1261  * hibernated on the volume, and -errno on error.
1262  */
1263 static int check_windows_hibernation_status(ntfs_volume *vol)
1264 {
1265         MFT_REF mref;
1266         struct inode *vi;
1267         struct page *page;
1268         u32 *kaddr, *kend;
1269         ntfs_name *name = NULL;
1270         int ret = 1;
1271         static const ntfschar hiberfil[13] = { cpu_to_le16('h'),
1272                         cpu_to_le16('i'), cpu_to_le16('b'),
1273                         cpu_to_le16('e'), cpu_to_le16('r'),
1274                         cpu_to_le16('f'), cpu_to_le16('i'),
1275                         cpu_to_le16('l'), cpu_to_le16('.'),
1276                         cpu_to_le16('s'), cpu_to_le16('y'),
1277                         cpu_to_le16('s'), 0 };
1278 
1279         ntfs_debug("Entering.");
1280         /*
1281          * Find the inode number for the hibernation file by looking up the
1282          * filename hiberfil.sys in the root directory.
1283          */
1284         mutex_lock(&vol->root_ino->i_mutex);
1285         mref = ntfs_lookup_inode_by_name(NTFS_I(vol->root_ino), hiberfil, 12,
1286                         &name);
1287         mutex_unlock(&vol->root_ino->i_mutex);
1288         if (IS_ERR_MREF(mref)) {
1289                 ret = MREF_ERR(mref);
1290                 /* If the file does not exist, Windows is not hibernated. */
1291                 if (ret == -ENOENT) {
1292                         ntfs_debug("hiberfil.sys not present.  Windows is not "
1293                                         "hibernated on the volume.");
1294                         return 0;
1295                 }
1296                 /* A real error occurred. */
1297                 ntfs_error(vol->sb, "Failed to find inode number for "
1298                                 "hiberfil.sys.");
1299                 return ret;
1300         }
1301         /* We do not care for the type of match that was found. */
1302         kfree(name);
1303         /* Get the inode. */
1304         vi = ntfs_iget(vol->sb, MREF(mref));
1305         if (IS_ERR(vi) || is_bad_inode(vi)) {
1306                 if (!IS_ERR(vi))
1307                         iput(vi);
1308                 ntfs_error(vol->sb, "Failed to load hiberfil.sys.");
1309                 return IS_ERR(vi) ? PTR_ERR(vi) : -EIO;
1310         }
1311         if (unlikely(i_size_read(vi) < NTFS_HIBERFIL_HEADER_SIZE)) {
1312                 ntfs_debug("hiberfil.sys is smaller than 4kiB (0x%llx).  "
1313                                 "Windows is hibernated on the volume.  This "
1314                                 "is not the system volume.", i_size_read(vi));
1315                 goto iput_out;
1316         }
1317         page = ntfs_map_page(vi->i_mapping, 0);
1318         if (IS_ERR(page)) {
1319                 ntfs_error(vol->sb, "Failed to read from hiberfil.sys.");
1320                 ret = PTR_ERR(page);
1321                 goto iput_out;
1322         }
1323         kaddr = (u32*)page_address(page);
1324         if (*(le32*)kaddr == cpu_to_le32(0x72626968)/*'hibr'*/) {
1325                 ntfs_debug("Magic \"hibr\" found in hiberfil.sys.  Windows is "
1326                                 "hibernated on the volume.  This is the "
1327                                 "system volume.");
1328                 goto unm_iput_out;
1329         }
1330         kend = kaddr + NTFS_HIBERFIL_HEADER_SIZE/sizeof(*kaddr);
1331         do {
1332                 if (unlikely(*kaddr)) {
1333                         ntfs_debug("hiberfil.sys is larger than 4kiB "
1334                                         "(0x%llx), does not contain the "
1335                                         "\"hibr\" magic, and does not have a "
1336                                         "zero header.  Windows is hibernated "
1337                                         "on the volume.  This is not the "
1338                                         "system volume.", i_size_read(vi));
1339                         goto unm_iput_out;
1340                 }
1341         } while (++kaddr < kend);
1342         ntfs_debug("hiberfil.sys contains a zero header.  Windows is not "
1343                         "hibernated on the volume.  This is the system "
1344                         "volume.");
1345         ret = 0;
1346 unm_iput_out:
1347         ntfs_unmap_page(page);
1348 iput_out:
1349         iput(vi);
1350         return ret;
1351 }
1352 
1353 /**
1354  * load_and_init_quota - load and setup the quota file for a volume if present
1355  * @vol:        ntfs super block describing device whose quota file to load
1356  *
1357  * Return 'true' on success or 'false' on error.  If $Quota is not present, we
1358  * leave vol->quota_ino as NULL and return success.
1359  */
1360 static bool load_and_init_quota(ntfs_volume *vol)
1361 {
1362         MFT_REF mref;
1363         struct inode *tmp_ino;
1364         ntfs_name *name = NULL;
1365         static const ntfschar Quota[7] = { cpu_to_le16('$'),
1366                         cpu_to_le16('Q'), cpu_to_le16('u'),
1367                         cpu_to_le16('o'), cpu_to_le16('t'),
1368                         cpu_to_le16('a'), 0 };
1369         static ntfschar Q[3] = { cpu_to_le16('$'),
1370                         cpu_to_le16('Q'), 0 };
1371 
1372         ntfs_debug("Entering.");
1373         /*
1374          * Find the inode number for the quota file by looking up the filename
1375          * $Quota in the extended system files directory $Extend.
1376          */
1377         mutex_lock(&vol->extend_ino->i_mutex);
1378         mref = ntfs_lookup_inode_by_name(NTFS_I(vol->extend_ino), Quota, 6,
1379                         &name);
1380         mutex_unlock(&vol->extend_ino->i_mutex);
1381         if (IS_ERR_MREF(mref)) {
1382                 /*
1383                  * If the file does not exist, quotas are disabled and have
1384                  * never been enabled on this volume, just return success.
1385                  */
1386                 if (MREF_ERR(mref) == -ENOENT) {
1387                         ntfs_debug("$Quota not present.  Volume does not have "
1388                                         "quotas enabled.");
1389                         /*
1390                          * No need to try to set quotas out of date if they are
1391                          * not enabled.
1392                          */
1393                         NVolSetQuotaOutOfDate(vol);
1394                         return true;
1395                 }
1396                 /* A real error occurred. */
1397                 ntfs_error(vol->sb, "Failed to find inode number for $Quota.");
1398                 return false;
1399         }
1400         /* We do not care for the type of match that was found. */
1401         kfree(name);
1402         /* Get the inode. */
1403         tmp_ino = ntfs_iget(vol->sb, MREF(mref));
1404         if (IS_ERR(tmp_ino) || is_bad_inode(tmp_ino)) {
1405                 if (!IS_ERR(tmp_ino))
1406                         iput(tmp_ino);
1407                 ntfs_error(vol->sb, "Failed to load $Quota.");
1408                 return false;
1409         }
1410         vol->quota_ino = tmp_ino;
1411         /* Get the $Q index allocation attribute. */
1412         tmp_ino = ntfs_index_iget(vol->quota_ino, Q, 2);
1413         if (IS_ERR(tmp_ino)) {
1414                 ntfs_error(vol->sb, "Failed to load $Quota/$Q index.");
1415                 return false;
1416         }
1417         vol->quota_q_ino = tmp_ino;
1418         ntfs_debug("Done.");
1419         return true;
1420 }
1421 
1422 /**
1423  * load_and_init_usnjrnl - load and setup the transaction log if present
1424  * @vol:        ntfs super block describing device whose usnjrnl file to load
1425  *
1426  * Return 'true' on success or 'false' on error.
1427  *
1428  * If $UsnJrnl is not present or in the process of being disabled, we set
1429  * NVolUsnJrnlStamped() and return success.
1430  *
1431  * If the $UsnJrnl $DATA/$J attribute has a size equal to the lowest valid usn,
1432  * i.e. transaction logging has only just been enabled or the journal has been
1433  * stamped and nothing has been logged since, we also set NVolUsnJrnlStamped()
1434  * and return success.
1435  */
1436 static bool load_and_init_usnjrnl(ntfs_volume *vol)
1437 {
1438         MFT_REF mref;
1439         struct inode *tmp_ino;
1440         ntfs_inode *tmp_ni;
1441         struct page *page;
1442         ntfs_name *name = NULL;
1443         USN_HEADER *uh;
1444         static const ntfschar UsnJrnl[9] = { cpu_to_le16('$'),
1445                         cpu_to_le16('U'), cpu_to_le16('s'),
1446                         cpu_to_le16('n'), cpu_to_le16('J'),
1447                         cpu_to_le16('r'), cpu_to_le16('n'),
1448                         cpu_to_le16('l'), 0 };
1449         static ntfschar Max[5] = { cpu_to_le16('$'),
1450                         cpu_to_le16('M'), cpu_to_le16('a'),
1451                         cpu_to_le16('x'), 0 };
1452         static ntfschar J[3] = { cpu_to_le16('$'),
1453                         cpu_to_le16('J'), 0 };
1454 
1455         ntfs_debug("Entering.");
1456         /*
1457          * Find the inode number for the transaction log file by looking up the
1458          * filename $UsnJrnl in the extended system files directory $Extend.
1459          */
1460         mutex_lock(&vol->extend_ino->i_mutex);
1461         mref = ntfs_lookup_inode_by_name(NTFS_I(vol->extend_ino), UsnJrnl, 8,
1462                         &name);
1463         mutex_unlock(&vol->extend_ino->i_mutex);
1464         if (IS_ERR_MREF(mref)) {
1465                 /*
1466                  * If the file does not exist, transaction logging is disabled,
1467                  * just return success.
1468                  */
1469                 if (MREF_ERR(mref) == -ENOENT) {
1470                         ntfs_debug("$UsnJrnl not present.  Volume does not "
1471                                         "have transaction logging enabled.");
1472 not_enabled:
1473                         /*
1474                          * No need to try to stamp the transaction log if
1475                          * transaction logging is not enabled.
1476                          */
1477                         NVolSetUsnJrnlStamped(vol);
1478                         return true;
1479                 }
1480                 /* A real error occurred. */
1481                 ntfs_error(vol->sb, "Failed to find inode number for "
1482                                 "$UsnJrnl.");
1483                 return false;
1484         }
1485         /* We do not care for the type of match that was found. */
1486         kfree(name);
1487         /* Get the inode. */
1488         tmp_ino = ntfs_iget(vol->sb, MREF(mref));
1489         if (unlikely(IS_ERR(tmp_ino) || is_bad_inode(tmp_ino))) {
1490                 if (!IS_ERR(tmp_ino))
1491                         iput(tmp_ino);
1492                 ntfs_error(vol->sb, "Failed to load $UsnJrnl.");
1493                 return false;
1494         }
1495         vol->usnjrnl_ino = tmp_ino;
1496         /*
1497          * If the transaction log is in the process of being deleted, we can
1498          * ignore it.
1499          */
1500         if (unlikely(vol->vol_flags & VOLUME_DELETE_USN_UNDERWAY)) {
1501                 ntfs_debug("$UsnJrnl in the process of being disabled.  "
1502                                 "Volume does not have transaction logging "
1503                                 "enabled.");
1504                 goto not_enabled;
1505         }
1506         /* Get the $DATA/$Max attribute. */
1507         tmp_ino = ntfs_attr_iget(vol->usnjrnl_ino, AT_DATA, Max, 4);
1508         if (IS_ERR(tmp_ino)) {
1509                 ntfs_error(vol->sb, "Failed to load $UsnJrnl/$DATA/$Max "
1510                                 "attribute.");
1511                 return false;
1512         }
1513         vol->usnjrnl_max_ino = tmp_ino;
1514         if (unlikely(i_size_read(tmp_ino) < sizeof(USN_HEADER))) {
1515                 ntfs_error(vol->sb, "Found corrupt $UsnJrnl/$DATA/$Max "
1516                                 "attribute (size is 0x%llx but should be at "
1517                                 "least 0x%zx bytes).", i_size_read(tmp_ino),
1518                                 sizeof(USN_HEADER));
1519                 return false;
1520         }
1521         /* Get the $DATA/$J attribute. */
1522         tmp_ino = ntfs_attr_iget(vol->usnjrnl_ino, AT_DATA, J, 2);
1523         if (IS_ERR(tmp_ino)) {
1524                 ntfs_error(vol->sb, "Failed to load $UsnJrnl/$DATA/$J "
1525                                 "attribute.");
1526                 return false;
1527         }
1528         vol->usnjrnl_j_ino = tmp_ino;
1529         /* Verify $J is non-resident and sparse. */
1530         tmp_ni = NTFS_I(vol->usnjrnl_j_ino);
1531         if (unlikely(!NInoNonResident(tmp_ni) || !NInoSparse(tmp_ni))) {
1532                 ntfs_error(vol->sb, "$UsnJrnl/$DATA/$J attribute is resident "
1533                                 "and/or not sparse.");
1534                 return false;
1535         }
1536         /* Read the USN_HEADER from $DATA/$Max. */
1537         page = ntfs_map_page(vol->usnjrnl_max_ino->i_mapping, 0);
1538         if (IS_ERR(page)) {
1539                 ntfs_error(vol->sb, "Failed to read from $UsnJrnl/$DATA/$Max "
1540                                 "attribute.");
1541                 return false;
1542         }
1543         uh = (USN_HEADER*)page_address(page);
1544         /* Sanity check the $Max. */
1545         if (unlikely(sle64_to_cpu(uh->allocation_delta) >
1546                         sle64_to_cpu(uh->maximum_size))) {
1547                 ntfs_error(vol->sb, "Allocation delta (0x%llx) exceeds "
1548                                 "maximum size (0x%llx).  $UsnJrnl is corrupt.",
1549                                 (long long)sle64_to_cpu(uh->allocation_delta),
1550                                 (long long)sle64_to_cpu(uh->maximum_size));
1551                 ntfs_unmap_page(page);
1552                 return false;
1553         }
1554         /*
1555          * If the transaction log has been stamped and nothing has been written
1556          * to it since, we do not need to stamp it.
1557          */
1558         if (unlikely(sle64_to_cpu(uh->lowest_valid_usn) >=
1559                         i_size_read(vol->usnjrnl_j_ino))) {
1560                 if (likely(sle64_to_cpu(uh->lowest_valid_usn) ==
1561                                 i_size_read(vol->usnjrnl_j_ino))) {
1562                         ntfs_unmap_page(page);
1563                         ntfs_debug("$UsnJrnl is enabled but nothing has been "
1564                                         "logged since it was last stamped.  "
1565                                         "Treating this as if the volume does "
1566                                         "not have transaction logging "
1567                                         "enabled.");
1568                         goto not_enabled;
1569                 }
1570                 ntfs_error(vol->sb, "$UsnJrnl has lowest valid usn (0x%llx) "
1571                                 "which is out of bounds (0x%llx).  $UsnJrnl "
1572                                 "is corrupt.",
1573                                 (long long)sle64_to_cpu(uh->lowest_valid_usn),
1574                                 i_size_read(vol->usnjrnl_j_ino));
1575                 ntfs_unmap_page(page);
1576                 return false;
1577         }
1578         ntfs_unmap_page(page);
1579         ntfs_debug("Done.");
1580         return true;
1581 }
1582 
1583 /**
1584  * load_and_init_attrdef - load the attribute definitions table for a volume
1585  * @vol:        ntfs super block describing device whose attrdef to load
1586  *
1587  * Return 'true' on success or 'false' on error.
1588  */
1589 static bool load_and_init_attrdef(ntfs_volume *vol)
1590 {
1591         loff_t i_size;
1592         struct super_block *sb = vol->sb;
1593         struct inode *ino;
1594         struct page *page;
1595         pgoff_t index, max_index;
1596         unsigned int size;
1597 
1598         ntfs_debug("Entering.");
1599         /* Read attrdef table and setup vol->attrdef and vol->attrdef_size. */
1600         ino = ntfs_iget(sb, FILE_AttrDef);
1601         if (IS_ERR(ino) || is_bad_inode(ino)) {
1602                 if (!IS_ERR(ino))
1603                         iput(ino);
1604                 goto failed;
1605         }
1606         NInoSetSparseDisabled(NTFS_I(ino));
1607         /* The size of FILE_AttrDef must be above 0 and fit inside 31 bits. */
1608         i_size = i_size_read(ino);
1609         if (i_size <= 0 || i_size > 0x7fffffff)
1610                 goto iput_failed;
1611         vol->attrdef = (ATTR_DEF*)ntfs_malloc_nofs(i_size);
1612         if (!vol->attrdef)
1613                 goto iput_failed;
1614         index = 0;
1615         max_index = i_size >> PAGE_CACHE_SHIFT;
1616         size = PAGE_CACHE_SIZE;
1617         while (index < max_index) {
1618                 /* Read the attrdef table and copy it into the linear buffer. */
1619 read_partial_attrdef_page:
1620                 page = ntfs_map_page(ino->i_mapping, index);
1621                 if (IS_ERR(page))
1622                         goto free_iput_failed;
1623                 memcpy((u8*)vol->attrdef + (index++ << PAGE_CACHE_SHIFT),
1624                                 page_address(page), size);
1625                 ntfs_unmap_page(page);
1626         };
1627         if (size == PAGE_CACHE_SIZE) {
1628                 size = i_size & ~PAGE_CACHE_MASK;
1629                 if (size)
1630                         goto read_partial_attrdef_page;
1631         }
1632         vol->attrdef_size = i_size;
1633         ntfs_debug("Read %llu bytes from $AttrDef.", i_size);
1634         iput(ino);
1635         return true;
1636 free_iput_failed:
1637         ntfs_free(vol->attrdef);
1638         vol->attrdef = NULL;
1639 iput_failed:
1640         iput(ino);
1641 failed:
1642         ntfs_error(sb, "Failed to initialize attribute definition table.");
1643         return false;
1644 }
1645 
1646 #endif /* NTFS_RW */
1647 
1648 /**
1649  * load_and_init_upcase - load the upcase table for an ntfs volume
1650  * @vol:        ntfs super block describing device whose upcase to load
1651  *
1652  * Return 'true' on success or 'false' on error.
1653  */
1654 static bool load_and_init_upcase(ntfs_volume *vol)
1655 {
1656         loff_t i_size;
1657         struct super_block *sb = vol->sb;
1658         struct inode *ino;
1659         struct page *page;
1660         pgoff_t index, max_index;
1661         unsigned int size;
1662         int i, max;
1663 
1664         ntfs_debug("Entering.");
1665         /* Read upcase table and setup vol->upcase and vol->upcase_len. */
1666         ino = ntfs_iget(sb, FILE_UpCase);
1667         if (IS_ERR(ino) || is_bad_inode(ino)) {
1668                 if (!IS_ERR(ino))
1669                         iput(ino);
1670                 goto upcase_failed;
1671         }
1672         /*
1673          * The upcase size must not be above 64k Unicode characters, must not
1674          * be zero and must be a multiple of sizeof(ntfschar).
1675          */
1676         i_size = i_size_read(ino);
1677         if (!i_size || i_size & (sizeof(ntfschar) - 1) ||
1678                         i_size > 64ULL * 1024 * sizeof(ntfschar))
1679                 goto iput_upcase_failed;
1680         vol->upcase = (ntfschar*)ntfs_malloc_nofs(i_size);
1681         if (!vol->upcase)
1682                 goto iput_upcase_failed;
1683         index = 0;
1684         max_index = i_size >> PAGE_CACHE_SHIFT;
1685         size = PAGE_CACHE_SIZE;
1686         while (index < max_index) {
1687                 /* Read the upcase table and copy it into the linear buffer. */
1688 read_partial_upcase_page:
1689                 page = ntfs_map_page(ino->i_mapping, index);
1690                 if (IS_ERR(page))
1691                         goto iput_upcase_failed;
1692                 memcpy((char*)vol->upcase + (index++ << PAGE_CACHE_SHIFT),
1693                                 page_address(page), size);
1694                 ntfs_unmap_page(page);
1695         };
1696         if (size == PAGE_CACHE_SIZE) {
1697                 size = i_size & ~PAGE_CACHE_MASK;
1698                 if (size)
1699                         goto read_partial_upcase_page;
1700         }
1701         vol->upcase_len = i_size >> UCHAR_T_SIZE_BITS;
1702         ntfs_debug("Read %llu bytes from $UpCase (expected %zu bytes).",
1703                         i_size, 64 * 1024 * sizeof(ntfschar));
1704         iput(ino);
1705         mutex_lock(&ntfs_lock);
1706         if (!default_upcase) {
1707                 ntfs_debug("Using volume specified $UpCase since default is "
1708                                 "not present.");
1709                 mutex_unlock(&ntfs_lock);
1710                 return true;
1711         }
1712         max = default_upcase_len;
1713         if (max > vol->upcase_len)
1714                 max = vol->upcase_len;
1715         for (i = 0; i < max; i++)
1716                 if (vol->upcase[i] != default_upcase[i])
1717                         break;
1718         if (i == max) {
1719                 ntfs_free(vol->upcase);
1720                 vol->upcase = default_upcase;
1721                 vol->upcase_len = max;
1722                 ntfs_nr_upcase_users++;
1723                 mutex_unlock(&ntfs_lock);
1724                 ntfs_debug("Volume specified $UpCase matches default. Using "
1725                                 "default.");
1726                 return true;
1727         }
1728         mutex_unlock(&ntfs_lock);
1729         ntfs_debug("Using volume specified $UpCase since it does not match "
1730                         "the default.");
1731         return true;
1732 iput_upcase_failed:
1733         iput(ino);
1734         ntfs_free(vol->upcase);
1735         vol->upcase = NULL;
1736 upcase_failed:
1737         mutex_lock(&ntfs_lock);
1738         if (default_upcase) {
1739                 vol->upcase = default_upcase;
1740                 vol->upcase_len = default_upcase_len;
1741                 ntfs_nr_upcase_users++;
1742                 mutex_unlock(&ntfs_lock);
1743                 ntfs_error(sb, "Failed to load $UpCase from the volume. Using "
1744                                 "default.");
1745                 return true;
1746         }
1747         mutex_unlock(&ntfs_lock);
1748         ntfs_error(sb, "Failed to initialize upcase table.");
1749         return false;
1750 }
1751 
1752 /*
1753  * The lcn and mft bitmap inodes are NTFS-internal inodes with
1754  * their own special locking rules:
1755  */
1756 static struct lock_class_key
1757         lcnbmp_runlist_lock_key, lcnbmp_mrec_lock_key,
1758         mftbmp_runlist_lock_key, mftbmp_mrec_lock_key;
1759 
1760 /**
1761  * load_system_files - open the system files using normal functions
1762  * @vol:        ntfs super block describing device whose system files to load
1763  *
1764  * Open the system files with normal access functions and complete setting up
1765  * the ntfs super block @vol.
1766  *
1767  * Return 'true' on success or 'false' on error.
1768  */
1769 static bool load_system_files(ntfs_volume *vol)
1770 {
1771         struct super_block *sb = vol->sb;
1772         MFT_RECORD *m;
1773         VOLUME_INFORMATION *vi;
1774         ntfs_attr_search_ctx *ctx;
1775 #ifdef NTFS_RW
1776         RESTART_PAGE_HEADER *rp;
1777         int err;
1778 #endif /* NTFS_RW */
1779 
1780         ntfs_debug("Entering.");
1781 #ifdef NTFS_RW
1782         /* Get mft mirror inode compare the contents of $MFT and $MFTMirr. */
1783         if (!load_and_init_mft_mirror(vol) || !check_mft_mirror(vol)) {
1784                 static const char *es1 = "Failed to load $MFTMirr";
1785                 static const char *es2 = "$MFTMirr does not match $MFT";
1786                 static const char *es3 = ".  Run ntfsfix and/or chkdsk.";
1787 
1788                 /* If a read-write mount, convert it to a read-only mount. */
1789                 if (!(sb->s_flags & MS_RDONLY)) {
1790                         if (!(vol->on_errors & (ON_ERRORS_REMOUNT_RO |
1791                                         ON_ERRORS_CONTINUE))) {
1792                                 ntfs_error(sb, "%s and neither on_errors="
1793                                                 "continue nor on_errors="
1794                                                 "remount-ro was specified%s",
1795                                                 !vol->mftmirr_ino ? es1 : es2,
1796                                                 es3);
1797                                 goto iput_mirr_err_out;
1798                         }
1799                         sb->s_flags |= MS_RDONLY;
1800                         ntfs_error(sb, "%s.  Mounting read-only%s",
1801                                         !vol->mftmirr_ino ? es1 : es2, es3);
1802                 } else
1803                         ntfs_warning(sb, "%s.  Will not be able to remount "
1804                                         "read-write%s",
1805                                         !vol->mftmirr_ino ? es1 : es2, es3);
1806                 /* This will prevent a read-write remount. */
1807                 NVolSetErrors(vol);
1808         }
1809 #endif /* NTFS_RW */
1810         /* Get mft bitmap attribute inode. */
1811         vol->mftbmp_ino = ntfs_attr_iget(vol->mft_ino, AT_BITMAP, NULL, 0);
1812         if (IS_ERR(vol->mftbmp_ino)) {
1813                 ntfs_error(sb, "Failed to load $MFT/$BITMAP attribute.");
1814                 goto iput_mirr_err_out;
1815         }
1816         lockdep_set_class(&NTFS_I(vol->mftbmp_ino)->runlist.lock,
1817                            &mftbmp_runlist_lock_key);
1818         lockdep_set_class(&NTFS_I(vol->mftbmp_ino)->mrec_lock,
1819                            &mftbmp_mrec_lock_key);
1820         /* Read upcase table and setup @vol->upcase and @vol->upcase_len. */
1821         if (!load_and_init_upcase(vol))
1822                 goto iput_mftbmp_err_out;
1823 #ifdef NTFS_RW
1824         /*
1825          * Read attribute definitions table and setup @vol->attrdef and
1826          * @vol->attrdef_size.
1827          */
1828         if (!load_and_init_attrdef(vol))
1829                 goto iput_upcase_err_out;
1830 #endif /* NTFS_RW */
1831         /*
1832          * Get the cluster allocation bitmap inode and verify the size, no
1833          * need for any locking at this stage as we are already running
1834          * exclusively as we are mount in progress task.
1835          */
1836         vol->lcnbmp_ino = ntfs_iget(sb, FILE_Bitmap);
1837         if (IS_ERR(vol->lcnbmp_ino) || is_bad_inode(vol->lcnbmp_ino)) {
1838                 if (!IS_ERR(vol->lcnbmp_ino))
1839                         iput(vol->lcnbmp_ino);
1840                 goto bitmap_failed;
1841         }
1842         lockdep_set_class(&NTFS_I(vol->lcnbmp_ino)->runlist.lock,
1843                            &lcnbmp_runlist_lock_key);
1844         lockdep_set_class(&NTFS_I(vol->lcnbmp_ino)->mrec_lock,
1845                            &lcnbmp_mrec_lock_key);
1846 
1847         NInoSetSparseDisabled(NTFS_I(vol->lcnbmp_ino));
1848         if ((vol->nr_clusters + 7) >> 3 > i_size_read(vol->lcnbmp_ino)) {
1849                 iput(vol->lcnbmp_ino);
1850 bitmap_failed:
1851                 ntfs_error(sb, "Failed to load $Bitmap.");
1852                 goto iput_attrdef_err_out;
1853         }
1854         /*
1855          * Get the volume inode and setup our cache of the volume flags and
1856          * version.
1857          */
1858         vol->vol_ino = ntfs_iget(sb, FILE_Volume);
1859         if (IS_ERR(vol->vol_ino) || is_bad_inode(vol->vol_ino)) {
1860                 if (!IS_ERR(vol->vol_ino))
1861                         iput(vol->vol_ino);
1862 volume_failed:
1863                 ntfs_error(sb, "Failed to load $Volume.");
1864                 goto iput_lcnbmp_err_out;
1865         }
1866         m = map_mft_record(NTFS_I(vol->vol_ino));
1867         if (IS_ERR(m)) {
1868 iput_volume_failed:
1869                 iput(vol->vol_ino);
1870                 goto volume_failed;
1871         }
1872         if (!(ctx = ntfs_attr_get_search_ctx(NTFS_I(vol->vol_ino), m))) {
1873                 ntfs_error(sb, "Failed to get attribute search context.");
1874                 goto get_ctx_vol_failed;
1875         }
1876         if (ntfs_attr_lookup(AT_VOLUME_INFORMATION, NULL, 0, 0, 0, NULL, 0,
1877                         ctx) || ctx->attr->non_resident || ctx->attr->flags) {
1878 err_put_vol:
1879                 ntfs_attr_put_search_ctx(ctx);
1880 get_ctx_vol_failed:
1881                 unmap_mft_record(NTFS_I(vol->vol_ino));
1882                 goto iput_volume_failed;
1883         }
1884         vi = (VOLUME_INFORMATION*)((char*)ctx->attr +
1885                         le16_to_cpu(ctx->attr->data.resident.value_offset));
1886         /* Some bounds checks. */
1887         if ((u8*)vi < (u8*)ctx->attr || (u8*)vi +
1888                         le32_to_cpu(ctx->attr->data.resident.value_length) >
1889                         (u8*)ctx->attr + le32_to_cpu(ctx->attr->length))
1890                 goto err_put_vol;
1891         /* Copy the volume flags and version to the ntfs_volume structure. */
1892         vol->vol_flags = vi->flags;
1893         vol->major_ver = vi->major_ver;
1894         vol->minor_ver = vi->minor_ver;
1895         ntfs_attr_put_search_ctx(ctx);
1896         unmap_mft_record(NTFS_I(vol->vol_ino));
1897         printk(KERN_INFO "NTFS volume version %i.%i.\n", vol->major_ver,
1898                         vol->minor_ver);
1899         if (vol->major_ver < 3 && NVolSparseEnabled(vol)) {
1900                 ntfs_warning(vol->sb, "Disabling sparse support due to NTFS "
1901                                 "volume version %i.%i (need at least version "
1902                                 "3.0).", vol->major_ver, vol->minor_ver);
1903                 NVolClearSparseEnabled(vol);
1904         }
1905 #ifdef NTFS_RW
1906         /* Make sure that no unsupported volume flags are set. */
1907         if (vol->vol_flags & VOLUME_MUST_MOUNT_RO_MASK) {
1908                 static const char *es1a = "Volume is dirty";
1909                 static const char *es1b = "Volume has been modified by chkdsk";
1910                 static const char *es1c = "Volume has unsupported flags set";
1911                 static const char *es2a = ".  Run chkdsk and mount in Windows.";
1912                 static const char *es2b = ".  Mount in Windows.";
1913                 const char *es1, *es2;
1914 
1915                 es2 = es2a;
1916                 if (vol->vol_flags & VOLUME_IS_DIRTY)
1917                         es1 = es1a;
1918                 else if (vol->vol_flags & VOLUME_MODIFIED_BY_CHKDSK) {
1919                         es1 = es1b;
1920                         es2 = es2b;
1921                 } else {
1922                         es1 = es1c;
1923                         ntfs_warning(sb, "Unsupported volume flags 0x%x "
1924                                         "encountered.",
1925                                         (unsigned)le16_to_cpu(vol->vol_flags));
1926                 }
1927                 /* If a read-write mount, convert it to a read-only mount. */
1928                 if (!(sb->s_flags & MS_RDONLY)) {
1929                         if (!(vol->on_errors & (ON_ERRORS_REMOUNT_RO |
1930                                         ON_ERRORS_CONTINUE))) {
1931                                 ntfs_error(sb, "%s and neither on_errors="
1932                                                 "continue nor on_errors="
1933                                                 "remount-ro was specified%s",
1934                                                 es1, es2);
1935                                 goto iput_vol_err_out;
1936                         }
1937                         sb->s_flags |= MS_RDONLY;
1938                         ntfs_error(sb, "%s.  Mounting read-only%s", es1, es2);
1939                 } else
1940                         ntfs_warning(sb, "%s.  Will not be able to remount "
1941                                         "read-write%s", es1, es2);
1942                 /*
1943                  * Do not set NVolErrors() because ntfs_remount() re-checks the
1944                  * flags which we need to do in case any flags have changed.
1945                  */
1946         }
1947         /*
1948          * Get the inode for the logfile, check it and determine if the volume
1949          * was shutdown cleanly.
1950          */
1951         rp = NULL;
1952         if (!load_and_check_logfile(vol, &rp) ||
1953                         !ntfs_is_logfile_clean(vol->logfile_ino, rp)) {
1954                 static const char *es1a = "Failed to load $LogFile";
1955                 static const char *es1b = "$LogFile is not clean";
1956                 static const char *es2 = ".  Mount in Windows.";
1957                 const char *es1;
1958 
1959                 es1 = !vol->logfile_ino ? es1a : es1b;
1960                 /* If a read-write mount, convert it to a read-only mount. */
1961                 if (!(sb->s_flags & MS_RDONLY)) {
1962                         if (!(vol->on_errors & (ON_ERRORS_REMOUNT_RO |
1963                                         ON_ERRORS_CONTINUE))) {
1964                                 ntfs_error(sb, "%s and neither on_errors="
1965                                                 "continue nor on_errors="
1966                                                 "remount-ro was specified%s",
1967                                                 es1, es2);
1968                                 if (vol->logfile_ino) {
1969                                         BUG_ON(!rp);
1970                                         ntfs_free(rp);
1971                                 }
1972                                 goto iput_logfile_err_out;
1973                         }
1974                         sb->s_flags |= MS_RDONLY;
1975                         ntfs_error(sb, "%s.  Mounting read-only%s", es1, es2);
1976                 } else
1977                         ntfs_warning(sb, "%s.  Will not be able to remount "
1978                                         "read-write%s", es1, es2);
1979                 /* This will prevent a read-write remount. */
1980                 NVolSetErrors(vol);
1981         }
1982         ntfs_free(rp);
1983 #endif /* NTFS_RW */
1984         /* Get the root directory inode so we can do path lookups. */
1985         vol->root_ino = ntfs_iget(sb, FILE_root);
1986         if (IS_ERR(vol->root_ino) || is_bad_inode(vol->root_ino)) {
1987                 if (!IS_ERR(vol->root_ino))
1988                         iput(vol->root_ino);
1989                 ntfs_error(sb, "Failed to load root directory.");
1990                 goto iput_logfile_err_out;
1991         }
1992 #ifdef NTFS_RW
1993         /*
1994          * Check if Windows is suspended to disk on the target volume.  If it
1995          * is hibernated, we must not write *anything* to the disk so set
1996          * NVolErrors() without setting the dirty volume flag and mount
1997          * read-only.  This will prevent read-write remounting and it will also
1998          * prevent all writes.
1999          */
2000         err = check_windows_hibernation_status(vol);
2001         if (unlikely(err)) {
2002                 static const char *es1a = "Failed to determine if Windows is "
2003                                 "hibernated";
2004                 static const char *es1b = "Windows is hibernated";
2005                 static const char *es2 = ".  Run chkdsk.";
2006                 const char *es1;
2007 
2008                 es1 = err < 0 ? es1a : es1b;
2009                 /* If a read-write mount, convert it to a read-only mount. */
2010                 if (!(sb->s_flags & MS_RDONLY)) {
2011                         if (!(vol->on_errors & (ON_ERRORS_REMOUNT_RO |
2012                                         ON_ERRORS_CONTINUE))) {
2013                                 ntfs_error(sb, "%s and neither on_errors="
2014                                                 "continue nor on_errors="
2015                                                 "remount-ro was specified%s",
2016                                                 es1, es2);
2017                                 goto iput_root_err_out;
2018                         }
2019                         sb->s_flags |= MS_RDONLY;
2020                         ntfs_error(sb, "%s.  Mounting read-only%s", es1, es2);
2021                 } else
2022                         ntfs_warning(sb, "%s.  Will not be able to remount "
2023                                         "read-write%s", es1, es2);
2024                 /* This will prevent a read-write remount. */
2025                 NVolSetErrors(vol);
2026         }
2027         /* If (still) a read-write mount, mark the volume dirty. */
2028         if (!(sb->s_flags & MS_RDONLY) &&
2029                         ntfs_set_volume_flags(vol, VOLUME_IS_DIRTY)) {
2030                 static const char *es1 = "Failed to set dirty bit in volume "
2031                                 "information flags";
2032                 static const char *es2 = ".  Run chkdsk.";
2033 
2034                 /* Convert to a read-only mount. */
2035                 if (!(vol->on_errors & (ON_ERRORS_REMOUNT_RO |
2036                                 ON_ERRORS_CONTINUE))) {
2037                         ntfs_error(sb, "%s and neither on_errors=continue nor "
2038                                         "on_errors=remount-ro was specified%s",
2039                                         es1, es2);
2040                         goto iput_root_err_out;
2041                 }
2042                 ntfs_error(sb, "%s.  Mounting read-only%s", es1, es2);
2043                 sb->s_flags |= MS_RDONLY;
2044                 /*
2045                  * Do not set NVolErrors() because ntfs_remount() might manage
2046                  * to set the dirty flag in which case all would be well.
2047                  */
2048         }
2049 #if 0
2050         // TODO: Enable this code once we start modifying anything that is
2051         //       different between NTFS 1.2 and 3.x...
2052         /*
2053          * If (still) a read-write mount, set the NT4 compatibility flag on
2054          * newer NTFS version volumes.
2055          */
2056         if (!(sb->s_flags & MS_RDONLY) && (vol->major_ver > 1) &&
2057                         ntfs_set_volume_flags(vol, VOLUME_MOUNTED_ON_NT4)) {
2058                 static const char *es1 = "Failed to set NT4 compatibility flag";
2059                 static const char *es2 = ".  Run chkdsk.";
2060 
2061                 /* Convert to a read-only mount. */
2062                 if (!(vol->on_errors & (ON_ERRORS_REMOUNT_RO |
2063                                 ON_ERRORS_CONTINUE))) {
2064                         ntfs_error(sb, "%s and neither on_errors=continue nor "
2065                                         "on_errors=remount-ro was specified%s",
2066                                         es1, es2);
2067                         goto iput_root_err_out;
2068                 }
2069                 ntfs_error(sb, "%s.  Mounting read-only%s", es1, es2);
2070                 sb->s_flags |= MS_RDONLY;
2071                 NVolSetErrors(vol);
2072         }
2073 #endif
2074         /* If (still) a read-write mount, empty the logfile. */
2075         if (!(sb->s_flags & MS_RDONLY) &&
2076                         !ntfs_empty_logfile(vol->logfile_ino)) {
2077                 static const char *es1 = "Failed to empty $LogFile";
2078                 static const char *es2 = ".  Mount in Windows.";
2079 
2080                 /* Convert to a read-only mount. */
2081                 if (!(vol->on_errors & (ON_ERRORS_REMOUNT_RO |
2082                                 ON_ERRORS_CONTINUE))) {
2083                         ntfs_error(sb, "%s and neither on_errors=continue nor "
2084                                         "on_errors=remount-ro was specified%s",
2085                                         es1, es2);
2086                         goto iput_root_err_out;
2087                 }
2088                 ntfs_error(sb, "%s.  Mounting read-only%s", es1, es2);
2089                 sb->s_flags |= MS_RDONLY;
2090                 NVolSetErrors(vol);
2091         }
2092 #endif /* NTFS_RW */
2093         /* If on NTFS versions before 3.0, we are done. */
2094         if (unlikely(vol->major_ver < 3))
2095                 return true;
2096         /* NTFS 3.0+ specific initialization. */
2097         /* Get the security descriptors inode. */
2098         vol->secure_ino = ntfs_iget(sb, FILE_Secure);
2099         if (IS_ERR(vol->secure_ino) || is_bad_inode(vol->secure_ino)) {
2100                 if (!IS_ERR(vol->secure_ino))
2101                         iput(vol->secure_ino);
2102                 ntfs_error(sb, "Failed to load $Secure.");
2103                 goto iput_root_err_out;
2104         }
2105         // TODO: Initialize security.
2106         /* Get the extended system files' directory inode. */
2107         vol->extend_ino = ntfs_iget(sb, FILE_Extend);
2108         if (IS_ERR(vol->extend_ino) || is_bad_inode(vol->extend_ino)) {
2109                 if (!IS_ERR(vol->extend_ino))
2110                         iput(vol->extend_ino);
2111                 ntfs_error(sb, "Failed to load $Extend.");
2112                 goto iput_sec_err_out;
2113         }
2114 #ifdef NTFS_RW
2115         /* Find the quota file, load it if present, and set it up. */
2116         if (!load_and_init_quota(vol)) {
2117                 static const char *es1 = "Failed to load $Quota";
2118                 static const char *es2 = ".  Run chkdsk.";
2119 
2120                 /* If a read-write mount, convert it to a read-only mount. */
2121                 if (!(sb->s_flags & MS_RDONLY)) {
2122                         if (!(vol->on_errors & (ON_ERRORS_REMOUNT_RO |
2123                                         ON_ERRORS_CONTINUE))) {
2124                                 ntfs_error(sb, "%s and neither on_errors="
2125                                                 "continue nor on_errors="
2126                                                 "remount-ro was specified%s",
2127                                                 es1, es2);
2128                                 goto iput_quota_err_out;
2129                         }
2130                         sb->s_flags |= MS_RDONLY;
2131                         ntfs_error(sb, "%s.  Mounting read-only%s", es1, es2);
2132                 } else
2133                         ntfs_warning(sb, "%s.  Will not be able to remount "
2134                                         "read-write%s", es1, es2);
2135                 /* This will prevent a read-write remount. */
2136                 NVolSetErrors(vol);
2137         }
2138         /* If (still) a read-write mount, mark the quotas out of date. */
2139         if (!(sb->s_flags & MS_RDONLY) &&
2140                         !ntfs_mark_quotas_out_of_date(vol)) {
2141                 static const char *es1 = "Failed to mark quotas out of date";
2142                 static const char *es2 = ".  Run chkdsk.";
2143 
2144                 /* Convert to a read-only mount. */
2145                 if (!(vol->on_errors & (ON_ERRORS_REMOUNT_RO |
2146                                 ON_ERRORS_CONTINUE))) {
2147                         ntfs_error(sb, "%s and neither on_errors=continue nor "
2148                                         "on_errors=remount-ro was specified%s",
2149                                         es1, es2);
2150                         goto iput_quota_err_out;
2151                 }
2152                 ntfs_error(sb, "%s.  Mounting read-only%s", es1, es2);
2153                 sb->s_flags |= MS_RDONLY;
2154                 NVolSetErrors(vol);
2155         }
2156         /*
2157          * Find the transaction log file ($UsnJrnl), load it if present, check
2158          * it, and set it up.
2159          */
2160         if (!load_and_init_usnjrnl(vol)) {
2161                 static const char *es1 = "Failed to load $UsnJrnl";
2162                 static const char *es2 = ".  Run chkdsk.";
2163 
2164                 /* If a read-write mount, convert it to a read-only mount. */
2165                 if (!(sb->s_flags & MS_RDONLY)) {
2166                         if (!(vol->on_errors & (ON_ERRORS_REMOUNT_RO |
2167                                         ON_ERRORS_CONTINUE))) {
2168                                 ntfs_error(sb, "%s and neither on_errors="
2169                                                 "continue nor on_errors="
2170                                                 "remount-ro was specified%s",
2171                                                 es1, es2);
2172                                 goto iput_usnjrnl_err_out;
2173                         }
2174                         sb->s_flags |= MS_RDONLY;
2175                         ntfs_error(sb, "%s.  Mounting read-only%s", es1, es2);
2176                 } else
2177                         ntfs_warning(sb, "%s.  Will not be able to remount "
2178                                         "read-write%s", es1, es2);
2179                 /* This will prevent a read-write remount. */
2180                 NVolSetErrors(vol);
2181         }
2182         /* If (still) a read-write mount, stamp the transaction log. */
2183         if (!(sb->s_flags & MS_RDONLY) && !ntfs_stamp_usnjrnl(vol)) {
2184                 static const char *es1 = "Failed to stamp transaction log "
2185                                 "($UsnJrnl)";
2186                 static const char *es2 = ".  Run chkdsk.";
2187 
2188                 /* Convert to a read-only mount. */
2189                 if (!(vol->on_errors & (ON_ERRORS_REMOUNT_RO |
2190                                 ON_ERRORS_CONTINUE))) {
2191                         ntfs_error(sb, "%s and neither on_errors=continue nor "
2192                                         "on_errors=remount-ro was specified%s",
2193                                         es1, es2);
2194                         goto iput_usnjrnl_err_out;
2195                 }
2196                 ntfs_error(sb, "%s.  Mounting read-only%s", es1, es2);
2197                 sb->s_flags |= MS_RDONLY;
2198                 NVolSetErrors(vol);
2199         }
2200 #endif /* NTFS_RW */
2201         return true;
2202 #ifdef NTFS_RW
2203 iput_usnjrnl_err_out:
2204         if (vol->usnjrnl_j_ino)
2205                 iput(vol->usnjrnl_j_ino);
2206         if (vol->usnjrnl_max_ino)
2207                 iput(vol->usnjrnl_max_ino);
2208         if (vol->usnjrnl_ino)
2209                 iput(vol->usnjrnl_ino);
2210 iput_quota_err_out:
2211         if (vol->quota_q_ino)
2212                 iput(vol->quota_q_ino);
2213         if (vol->quota_ino)
2214                 iput(vol->quota_ino);
2215         iput(vol->extend_ino);
2216 #endif /* NTFS_RW */
2217 iput_sec_err_out:
2218         iput(vol->secure_ino);
2219 iput_root_err_out:
2220         iput(vol->root_ino);
2221 iput_logfile_err_out:
2222 #ifdef NTFS_RW
2223         if (vol->logfile_ino)
2224                 iput(vol->logfile_ino);
2225 iput_vol_err_out:
2226 #endif /* NTFS_RW */
2227         iput(vol->vol_ino);
2228 iput_lcnbmp_err_out:
2229         iput(vol->lcnbmp_ino);
2230 iput_attrdef_err_out:
2231         vol->attrdef_size = 0;
2232         if (vol->attrdef) {
2233                 ntfs_free(vol->attrdef);
2234                 vol->attrdef = NULL;
2235         }
2236 #ifdef NTFS_RW
2237 iput_upcase_err_out:
2238 #endif /* NTFS_RW */
2239         vol->upcase_len = 0;
2240         mutex_lock(&ntfs_lock);
2241         if (vol->upcase == default_upcase) {
2242                 ntfs_nr_upcase_users--;
2243                 vol->upcase = NULL;
2244         }
2245         mutex_unlock(&ntfs_lock);
2246         if (vol->upcase) {
2247                 ntfs_free(vol->upcase);
2248                 vol->upcase = NULL;
2249         }
2250 iput_mftbmp_err_out:
2251         iput(vol->mftbmp_ino);
2252 iput_mirr_err_out:
2253 #ifdef NTFS_RW
2254         if (vol->mftmirr_ino)
2255                 iput(vol->mftmirr_ino);
2256 #endif /* NTFS_RW */
2257         return false;
2258 }
2259 
2260 /**
2261  * ntfs_put_super - called by the vfs to unmount a volume
2262  * @sb:         vfs superblock of volume to unmount
2263  *
2264  * ntfs_put_super() is called by the VFS (from fs/super.c::do_umount()) when
2265  * the volume is being unmounted (umount system call has been invoked) and it
2266  * releases all inodes and memory belonging to the NTFS specific part of the
2267  * super block.
2268  */
2269 static void ntfs_put_super(struct super_block *sb)
2270 {
2271         ntfs_volume *vol = NTFS_SB(sb);
2272 
2273         ntfs_debug("Entering.");
2274 
2275 #ifdef NTFS_RW
2276         /*
2277          * Commit all inodes while they are still open in case some of them
2278          * cause others to be dirtied.
2279          */
2280         ntfs_commit_inode(vol->vol_ino);
2281 
2282         /* NTFS 3.0+ specific. */
2283         if (vol->major_ver >= 3) {
2284                 if (vol->usnjrnl_j_ino)
2285                         ntfs_commit_inode(vol->usnjrnl_j_ino);
2286                 if (vol->usnjrnl_max_ino)
2287                         ntfs_commit_inode(vol->usnjrnl_max_ino);
2288                 if (vol->usnjrnl_ino)
2289                         ntfs_commit_inode(vol->usnjrnl_ino);
2290                 if (vol->quota_q_ino)
2291                         ntfs_commit_inode(vol->quota_q_ino);
2292                 if (vol->quota_ino)
2293                         ntfs_commit_inode(vol->quota_ino);
2294                 if (vol->extend_ino)
2295                         ntfs_commit_inode(vol->extend_ino);
2296                 if (vol->secure_ino)
2297                         ntfs_commit_inode(vol->secure_ino);
2298         }
2299 
2300         ntfs_commit_inode(vol->root_ino);
2301 
2302         down_write(&vol->lcnbmp_lock);
2303         ntfs_commit_inode(vol->lcnbmp_ino);
2304         up_write(&vol->lcnbmp_lock);
2305 
2306         down_write(&vol->mftbmp_lock);
2307         ntfs_commit_inode(vol->mftbmp_ino);
2308         up_write(&vol->mftbmp_lock);
2309 
2310         if (vol->logfile_ino)
2311                 ntfs_commit_inode(vol->logfile_ino);
2312 
2313         if (vol->mftmirr_ino)
2314                 ntfs_commit_inode(vol->mftmirr_ino);
2315         ntfs_commit_inode(vol->mft_ino);
2316 
2317         /*
2318          * If a read-write mount and no volume errors have occurred, mark the
2319          * volume clean.  Also, re-commit all affected inodes.
2320          */
2321         if (!(sb->s_flags & MS_RDONLY)) {
2322                 if (!NVolErrors(vol)) {
2323                         if (ntfs_clear_volume_flags(vol, VOLUME_IS_DIRTY))
2324                                 ntfs_warning(sb, "Failed to clear dirty bit "
2325                                                 "in volume information "
2326                                                 "flags.  Run chkdsk.");
2327                         ntfs_commit_inode(vol->vol_ino);
2328                         ntfs_commit_inode(vol->root_ino);
2329                         if (vol->mftmirr_ino)
2330                                 ntfs_commit_inode(vol->mftmirr_ino);
2331                         ntfs_commit_inode(vol->mft_ino);
2332                 } else {
2333                         ntfs_warning(sb, "Volume has errors.  Leaving volume "
2334                                         "marked dirty.  Run chkdsk.");
2335                 }
2336         }
2337 #endif /* NTFS_RW */
2338 
2339         iput(vol->vol_ino);
2340         vol->vol_ino = NULL;
2341 
2342         /* NTFS 3.0+ specific clean up. */
2343         if (vol->major_ver >= 3) {
2344 #ifdef NTFS_RW
2345                 if (vol->usnjrnl_j_ino) {
2346                         iput(vol->usnjrnl_j_ino);
2347                         vol->usnjrnl_j_ino = NULL;
2348                 }
2349                 if (vol->usnjrnl_max_ino) {
2350                         iput(vol->usnjrnl_max_ino);
2351                         vol->usnjrnl_max_ino = NULL;
2352                 }
2353                 if (vol->usnjrnl_ino) {
2354                         iput(vol->usnjrnl_ino);
2355                         vol->usnjrnl_ino = NULL;
2356                 }
2357                 if (vol->quota_q_ino) {
2358                         iput(vol->quota_q_ino);
2359                         vol->quota_q_ino = NULL;
2360                 }
2361                 if (vol->quota_ino) {
2362                         iput(vol->quota_ino);
2363                         vol->quota_ino = NULL;
2364                 }
2365 #endif /* NTFS_RW */
2366                 if (vol->extend_ino) {
2367                         iput(vol->extend_ino);
2368                         vol->extend_ino = NULL;
2369                 }
2370                 if (vol->secure_ino) {
2371                         iput(vol->secure_ino);
2372                         vol->secure_ino = NULL;
2373                 }
2374         }
2375 
2376         iput(vol->root_ino);
2377         vol->root_ino = NULL;
2378 
2379         down_write(&vol->lcnbmp_lock);
2380         iput(vol->lcnbmp_ino);
2381         vol->lcnbmp_ino = NULL;
2382         up_write(&vol->lcnbmp_lock);
2383 
2384         down_write(&vol->mftbmp_lock);
2385         iput(vol->mftbmp_ino);
2386         vol->mftbmp_ino = NULL;
2387         up_write(&vol->mftbmp_lock);
2388 
2389 #ifdef NTFS_RW
2390         if (vol->logfile_ino) {
2391                 iput(vol->logfile_ino);
2392                 vol->logfile_ino = NULL;
2393         }
2394         if (vol->mftmirr_ino) {
2395                 /* Re-commit the mft mirror and mft just in case. */
2396                 ntfs_commit_inode(vol->mftmirr_ino);
2397                 ntfs_commit_inode(vol->mft_ino);
2398                 iput(vol->mftmirr_ino);
2399                 vol->mftmirr_ino = NULL;
2400         }
2401         /*
2402          * We should have no dirty inodes left, due to
2403          * mft.c::ntfs_mft_writepage() cleaning all the dirty pages as
2404          * the underlying mft records are written out and cleaned.
2405          */
2406         ntfs_commit_inode(vol->mft_ino);
2407         write_inode_now(vol->mft_ino, 1);
2408 #endif /* NTFS_RW */
2409 
2410         iput(vol->mft_ino);
2411         vol->mft_ino = NULL;
2412 
2413         /* Throw away the table of attribute definitions. */
2414         vol->attrdef_size = 0;
2415         if (vol->attrdef) {
2416                 ntfs_free(vol->attrdef);
2417                 vol->attrdef = NULL;
2418         }
2419         vol->upcase_len = 0;
2420         /*
2421          * Destroy the global default upcase table if necessary.  Also decrease
2422          * the number of upcase users if we are a user.
2423          */
2424         mutex_lock(&ntfs_lock);
2425         if (vol->upcase == default_upcase) {
2426                 ntfs_nr_upcase_users--;
2427                 vol->upcase = NULL;
2428         }
2429         if (!ntfs_nr_upcase_users && default_upcase) {
2430                 ntfs_free(default_upcase);
2431                 default_upcase = NULL;
2432         }
2433         if (vol->cluster_size <= 4096 && !--ntfs_nr_compression_users)
2434                 free_compression_buffers();
2435         mutex_unlock(&ntfs_lock);
2436         if (vol->upcase) {
2437                 ntfs_free(vol->upcase);
2438                 vol->upcase = NULL;
2439         }
2440 
2441         unload_nls(vol->nls_map);
2442 
2443         sb->s_fs_info = NULL;
2444         kfree(vol);
2445 }
2446 
2447 /**
2448  * get_nr_free_clusters - return the number of free clusters on a volume
2449  * @vol:        ntfs volume for which to obtain free cluster count
2450  *
2451  * Calculate the number of free clusters on the mounted NTFS volume @vol. We
2452  * actually calculate the number of clusters in use instead because this
2453  * allows us to not care about partial pages as these will be just zero filled
2454  * and hence not be counted as allocated clusters.
2455  *
2456  * The only particularity is that clusters beyond the end of the logical ntfs
2457  * volume will be marked as allocated to prevent errors which means we have to
2458  * discount those at the end. This is important as the cluster bitmap always
2459  * has a size in multiples of 8 bytes, i.e. up to 63 clusters could be outside
2460  * the logical volume and marked in use when they are not as they do not exist.
2461  *
2462  * If any pages cannot be read we assume all clusters in the erroring pages are
2463  * in use. This means we return an underestimate on errors which is better than
2464  * an overestimate.
2465  */
2466 static s64 get_nr_free_clusters(ntfs_volume *vol)
2467 {
2468         s64 nr_free = vol->nr_clusters;
2469         struct address_space *mapping = vol->lcnbmp_ino->i_mapping;
2470         struct page *page;
2471         pgoff_t index, max_index;
2472 
2473         ntfs_debug("Entering.");
2474         /* Serialize accesses to the cluster bitmap. */
2475         down_read(&vol->lcnbmp_lock);
2476         /*
2477          * Convert the number of bits into bytes rounded up, then convert into
2478          * multiples of PAGE_CACHE_SIZE, rounding up so that if we have one
2479          * full and one partial page max_index = 2.
2480          */
2481         max_index = (((vol->nr_clusters + 7) >> 3) + PAGE_CACHE_SIZE - 1) >>
2482                         PAGE_CACHE_SHIFT;
2483         /* Use multiples of 4 bytes, thus max_size is PAGE_CACHE_SIZE / 4. */
2484         ntfs_debug("Reading $Bitmap, max_index = 0x%lx, max_size = 0x%lx.",
2485                         max_index, PAGE_CACHE_SIZE / 4);
2486         for (index = 0; index < max_index; index++) {
2487                 unsigned long *kaddr;
2488 
2489                 /*
2490                  * Read the page from page cache, getting it from backing store
2491                  * if necessary, and increment the use count.
2492                  */
2493                 page = read_mapping_page(mapping, index, NULL);
2494                 /* Ignore pages which errored synchronously. */
2495                 if (IS_ERR(page)) {
2496                         ntfs_debug("read_mapping_page() error. Skipping "
2497                                         "page (index 0x%lx).", index);
2498                         nr_free -= PAGE_CACHE_SIZE * 8;
2499                         continue;
2500                 }
2501                 kaddr = kmap_atomic(page);
2502                 /*
2503                  * Subtract the number of set bits. If this
2504                  * is the last page and it is partial we don't really care as
2505                  * it just means we do a little extra work but it won't affect
2506                  * the result as all out of range bytes are set to zero by
2507                  * ntfs_readpage().
2508                  */
2509                 nr_free -= bitmap_weight(kaddr,
2510                                         PAGE_CACHE_SIZE * BITS_PER_BYTE);
2511                 kunmap_atomic(kaddr);
2512                 page_cache_release(page);
2513         }
2514         ntfs_debug("Finished reading $Bitmap, last index = 0x%lx.", index - 1);
2515         /*
2516          * Fixup for eventual bits outside logical ntfs volume (see function
2517          * description above).
2518          */
2519         if (vol->nr_clusters & 63)
2520                 nr_free += 64 - (vol->nr_clusters & 63);
2521         up_read(&vol->lcnbmp_lock);
2522         /* If errors occurred we may well have gone below zero, fix this. */
2523         if (nr_free < 0)
2524                 nr_free = 0;
2525         ntfs_debug("Exiting.");
2526         return nr_free;
2527 }
2528 
2529 /**
2530  * __get_nr_free_mft_records - return the number of free inodes on a volume
2531  * @vol:        ntfs volume for which to obtain free inode count
2532  * @nr_free:    number of mft records in filesystem
2533  * @max_index:  maximum number of pages containing set bits
2534  *
2535  * Calculate the number of free mft records (inodes) on the mounted NTFS
2536  * volume @vol. We actually calculate the number of mft records in use instead
2537  * because this allows us to not care about partial pages as these will be just
2538  * zero filled and hence not be counted as allocated mft record.
2539  *
2540  * If any pages cannot be read we assume all mft records in the erroring pages
2541  * are in use. This means we return an underestimate on errors which is better
2542  * than an overestimate.
2543  *
2544  * NOTE: Caller must hold mftbmp_lock rw_semaphore for reading or writing.
2545  */
2546 static unsigned long __get_nr_free_mft_records(ntfs_volume *vol,
2547                 s64 nr_free, const pgoff_t max_index)
2548 {
2549         struct address_space *mapping = vol->mftbmp_ino->i_mapping;
2550         struct page *page;
2551         pgoff_t index;
2552 
2553         ntfs_debug("Entering.");
2554         /* Use multiples of 4 bytes, thus max_size is PAGE_CACHE_SIZE / 4. */
2555         ntfs_debug("Reading $MFT/$BITMAP, max_index = 0x%lx, max_size = "
2556                         "0x%lx.", max_index, PAGE_CACHE_SIZE / 4);
2557         for (index = 0; index < max_index; index++) {
2558                 unsigned long *kaddr;
2559 
2560                 /*
2561                  * Read the page from page cache, getting it from backing store
2562                  * if necessary, and increment the use count.
2563                  */
2564                 page = read_mapping_page(mapping, index, NULL);
2565                 /* Ignore pages which errored synchronously. */
2566                 if (IS_ERR(page)) {
2567                         ntfs_debug("read_mapping_page() error. Skipping "
2568                                         "page (index 0x%lx).", index);
2569                         nr_free -= PAGE_CACHE_SIZE * 8;
2570                         continue;
2571                 }
2572                 kaddr = kmap_atomic(page);
2573                 /*
2574                  * Subtract the number of set bits. If this
2575                  * is the last page and it is partial we don't really care as
2576                  * it just means we do a little extra work but it won't affect
2577                  * the result as all out of range bytes are set to zero by
2578                  * ntfs_readpage().
2579                  */
2580                 nr_free -= bitmap_weight(kaddr,
2581                                         PAGE_CACHE_SIZE * BITS_PER_BYTE);
2582                 kunmap_atomic(kaddr);
2583                 page_cache_release(page);
2584         }
2585         ntfs_debug("Finished reading $MFT/$BITMAP, last index = 0x%lx.",
2586                         index - 1);
2587         /* If errors occurred we may well have gone below zero, fix this. */
2588         if (nr_free < 0)
2589                 nr_free = 0;
2590         ntfs_debug("Exiting.");
2591         return nr_free;
2592 }
2593 
2594 /**
2595  * ntfs_statfs - return information about mounted NTFS volume
2596  * @dentry:     dentry from mounted volume
2597  * @sfs:        statfs structure in which to return the information
2598  *
2599  * Return information about the mounted NTFS volume @dentry in the statfs structure
2600  * pointed to by @sfs (this is initialized with zeros before ntfs_statfs is
2601  * called). We interpret the values to be correct of the moment in time at
2602  * which we are called. Most values are variable otherwise and this isn't just
2603  * the free values but the totals as well. For example we can increase the
2604  * total number of file nodes if we run out and we can keep doing this until
2605  * there is no more space on the volume left at all.
2606  *
2607  * Called from vfs_statfs which is used to handle the statfs, fstatfs, and
2608  * ustat system calls.
2609  *
2610  * Return 0 on success or -errno on error.
2611  */
2612 static int ntfs_statfs(struct dentry *dentry, struct kstatfs *sfs)
2613 {
2614         struct super_block *sb = dentry->d_sb;
2615         s64 size;
2616         ntfs_volume *vol = NTFS_SB(sb);
2617         ntfs_inode *mft_ni = NTFS_I(vol->mft_ino);
2618         pgoff_t max_index;
2619         unsigned long flags;
2620 
2621         ntfs_debug("Entering.");
2622         /* Type of filesystem. */
2623         sfs->f_type   = NTFS_SB_MAGIC;
2624         /* Optimal transfer block size. */
2625         sfs->f_bsize  = PAGE_CACHE_SIZE;
2626         /*
2627          * Total data blocks in filesystem in units of f_bsize and since
2628          * inodes are also stored in data blocs ($MFT is a file) this is just
2629          * the total clusters.
2630          */
2631         sfs->f_blocks = vol->nr_clusters << vol->cluster_size_bits >>
2632                                 PAGE_CACHE_SHIFT;
2633         /* Free data blocks in filesystem in units of f_bsize. */
2634         size          = get_nr_free_clusters(vol) << vol->cluster_size_bits >>
2635                                 PAGE_CACHE_SHIFT;
2636         if (size < 0LL)
2637                 size = 0LL;
2638         /* Free blocks avail to non-superuser, same as above on NTFS. */
2639         sfs->f_bavail = sfs->f_bfree = size;
2640         /* Serialize accesses to the inode bitmap. */
2641         down_read(&vol->mftbmp_lock);
2642         read_lock_irqsave(&mft_ni->size_lock, flags);
2643         size = i_size_read(vol->mft_ino) >> vol->mft_record_size_bits;
2644         /*
2645          * Convert the maximum number of set bits into bytes rounded up, then
2646          * convert into multiples of PAGE_CACHE_SIZE, rounding up so that if we
2647          * have one full and one partial page max_index = 2.
2648          */
2649         max_index = ((((mft_ni->initialized_size >> vol->mft_record_size_bits)
2650                         + 7) >> 3) + PAGE_CACHE_SIZE - 1) >> PAGE_CACHE_SHIFT;
2651         read_unlock_irqrestore(&mft_ni->size_lock, flags);
2652         /* Number of inodes in filesystem (at this point in time). */
2653         sfs->f_files = size;
2654         /* Free inodes in fs (based on current total count). */
2655         sfs->f_ffree = __get_nr_free_mft_records(vol, size, max_index);
2656         up_read(&vol->mftbmp_lock);
2657         /*
2658          * File system id. This is extremely *nix flavour dependent and even
2659          * within Linux itself all fs do their own thing. I interpret this to
2660          * mean a unique id associated with the mounted fs and not the id
2661          * associated with the filesystem driver, the latter is already given
2662          * by the filesystem type in sfs->f_type. Thus we use the 64-bit
2663          * volume serial number splitting it into two 32-bit parts. We enter
2664          * the least significant 32-bits in f_fsid[0] and the most significant
2665          * 32-bits in f_fsid[1].
2666          */
2667         sfs->f_fsid.val[0] = vol->serial_no & 0xffffffff;
2668         sfs->f_fsid.val[1] = (vol->serial_no >> 32) & 0xffffffff;
2669         /* Maximum length of filenames. */
2670         sfs->f_namelen     = NTFS_MAX_NAME_LEN;
2671         return 0;
2672 }
2673 
2674 #ifdef NTFS_RW
2675 static int ntfs_write_inode(struct inode *vi, struct writeback_control *wbc)
2676 {
2677         return __ntfs_write_inode(vi, wbc->sync_mode == WB_SYNC_ALL);
2678 }
2679 #endif
2680 
2681 /**
2682  * The complete super operations.
2683  */
2684 static const struct super_operations ntfs_sops = {
2685         .alloc_inode    = ntfs_alloc_big_inode,   /* VFS: Allocate new inode. */
2686         .destroy_inode  = ntfs_destroy_big_inode, /* VFS: Deallocate inode. */
2687 #ifdef NTFS_RW
2688         .write_inode    = ntfs_write_inode,     /* VFS: Write dirty inode to
2689                                                    disk. */
2690 #endif /* NTFS_RW */
2691         .put_super      = ntfs_put_super,       /* Syscall: umount. */
2692         .statfs         = ntfs_statfs,          /* Syscall: statfs */
2693         .remount_fs     = ntfs_remount,         /* Syscall: mount -o remount. */
2694         .evict_inode    = ntfs_evict_big_inode, /* VFS: Called when an inode is
2695                                                    removed from memory. */
2696         .show_options   = ntfs_show_options,    /* Show mount options in
2697                                                    proc. */
2698 };
2699 
2700 /**
2701  * ntfs_fill_super - mount an ntfs filesystem
2702  * @sb:         super block of ntfs filesystem to mount
2703  * @opt:        string containing the mount options
2704  * @silent:     silence error output
2705  *
2706  * ntfs_fill_super() is called by the VFS to mount the device described by @sb
2707  * with the mount otions in @data with the NTFS filesystem.
2708  *
2709  * If @silent is true, remain silent even if errors are detected. This is used
2710  * during bootup, when the kernel tries to mount the root filesystem with all
2711  * registered filesystems one after the other until one succeeds. This implies
2712  * that all filesystems except the correct one will quite correctly and
2713  * expectedly return an error, but nobody wants to see error messages when in
2714  * fact this is what is supposed to happen.
2715  *
2716  * NOTE: @sb->s_flags contains the mount options flags.
2717  */
2718 static int ntfs_fill_super(struct super_block *sb, void *opt, const int silent)
2719 {
2720         ntfs_volume *vol;
2721         struct buffer_head *bh;
2722         struct inode *tmp_ino;
2723         int blocksize, result;
2724 
2725         /*
2726          * We do a pretty difficult piece of bootstrap by reading the
2727          * MFT (and other metadata) from disk into memory. We'll only
2728          * release this metadata during umount, so the locking patterns
2729          * observed during bootstrap do not count. So turn off the
2730          * observation of locking patterns (strictly for this context
2731          * only) while mounting NTFS. [The validator is still active
2732          * otherwise, even for this context: it will for example record
2733          * lock class registrations.]
2734          */
2735         lockdep_off();
2736         ntfs_debug("Entering.");
2737 #ifndef NTFS_RW
2738         sb->s_flags |= MS_RDONLY;
2739 #endif /* ! NTFS_RW */
2740         /* Allocate a new ntfs_volume and place it in sb->s_fs_info. */
2741         sb->s_fs_info = kmalloc(sizeof(ntfs_volume), GFP_NOFS);
2742         vol = NTFS_SB(sb);
2743         if (!vol) {
2744                 if (!silent)
2745                         ntfs_error(sb, "Allocation of NTFS volume structure "
2746                                         "failed. Aborting mount...");
2747                 lockdep_on();
2748                 return -ENOMEM;
2749         }
2750         /* Initialize ntfs_volume structure. */
2751         *vol = (ntfs_volume) {
2752                 .sb = sb,
2753                 /*
2754                  * Default is group and other don't have any access to files or
2755                  * directories while owner has full access. Further, files by
2756                  * default are not executable but directories are of course
2757                  * browseable.
2758                  */
2759                 .fmask = 0177,
2760                 .dmask = 0077,
2761         };
2762         init_rwsem(&vol->mftbmp_lock);
2763         init_rwsem(&vol->lcnbmp_lock);
2764 
2765         /* By default, enable sparse support. */
2766         NVolSetSparseEnabled(vol);
2767 
2768         /* Important to get the mount options dealt with now. */
2769         if (!parse_options(vol, (char*)opt))
2770                 goto err_out_now;
2771 
2772         /* We support sector sizes up to the PAGE_CACHE_SIZE. */
2773         if (bdev_logical_block_size(sb->s_bdev) > PAGE_CACHE_SIZE) {
2774                 if (!silent)
2775                         ntfs_error(sb, "Device has unsupported sector size "
2776                                         "(%i).  The maximum supported sector "
2777                                         "size on this architecture is %lu "
2778                                         "bytes.",
2779                                         bdev_logical_block_size(sb->s_bdev),
2780                                         PAGE_CACHE_SIZE);
2781                 goto err_out_now;
2782         }
2783         /*
2784          * Setup the device access block size to NTFS_BLOCK_SIZE or the hard
2785          * sector size, whichever is bigger.
2786          */
2787         blocksize = sb_min_blocksize(sb, NTFS_BLOCK_SIZE);
2788         if (blocksize < NTFS_BLOCK_SIZE) {
2789                 if (!silent)
2790                         ntfs_error(sb, "Unable to set device block size.");
2791                 goto err_out_now;
2792         }
2793         BUG_ON(blocksize != sb->s_blocksize);
2794         ntfs_debug("Set device block size to %i bytes (block size bits %i).",
2795                         blocksize, sb->s_blocksize_bits);
2796         /* Determine the size of the device in units of block_size bytes. */
2797         if (!i_size_read(sb->s_bdev->bd_inode)) {
2798                 if (!silent)
2799                         ntfs_error(sb, "Unable to determine device size.");
2800                 goto err_out_now;
2801         }
2802         vol->nr_blocks = i_size_read(sb->s_bdev->bd_inode) >>
2803                         sb->s_blocksize_bits;
2804         /* Read the boot sector and return unlocked buffer head to it. */
2805         if (!(bh = read_ntfs_boot_sector(sb, silent))) {
2806                 if (!silent)
2807                         ntfs_error(sb, "Not an NTFS volume.");
2808                 goto err_out_now;
2809         }
2810         /*
2811          * Extract the data from the boot sector and setup the ntfs volume
2812          * using it.
2813          */
2814         result = parse_ntfs_boot_sector(vol, (NTFS_BOOT_SECTOR*)bh->b_data);
2815         brelse(bh);
2816         if (!result) {
2817                 if (!silent)
2818                         ntfs_error(sb, "Unsupported NTFS filesystem.");
2819                 goto err_out_now;
2820         }
2821         /*
2822          * If the boot sector indicates a sector size bigger than the current
2823          * device block size, switch the device block size to the sector size.
2824          * TODO: It may be possible to support this case even when the set
2825          * below fails, we would just be breaking up the i/o for each sector
2826          * into multiple blocks for i/o purposes but otherwise it should just
2827          * work.  However it is safer to leave disabled until someone hits this
2828          * error message and then we can get them to try it without the setting
2829          * so we know for sure that it works.
2830          */
2831         if (vol->sector_size > blocksize) {
2832                 blocksize = sb_set_blocksize(sb, vol->sector_size);
2833                 if (blocksize != vol->sector_size) {
2834                         if (!silent)
2835                                 ntfs_error(sb, "Unable to set device block "
2836                                                 "size to sector size (%i).",
2837                                                 vol->sector_size);
2838                         goto err_out_now;
2839                 }
2840                 BUG_ON(blocksize != sb->s_blocksize);
2841                 vol->nr_blocks = i_size_read(sb->s_bdev->bd_inode) >>
2842                                 sb->s_blocksize_bits;
2843                 ntfs_debug("Changed device block size to %i bytes (block size "
2844                                 "bits %i) to match volume sector size.",
2845                                 blocksize, sb->s_blocksize_bits);
2846         }
2847         /* Initialize the cluster and mft allocators. */
2848         ntfs_setup_allocators(vol);
2849         /* Setup remaining fields in the super block. */
2850         sb->s_magic = NTFS_SB_MAGIC;
2851         /*
2852          * Ntfs allows 63 bits for the file size, i.e. correct would be:
2853          *      sb->s_maxbytes = ~0ULL >> 1;
2854          * But the kernel uses a long as the page cache page index which on
2855          * 32-bit architectures is only 32-bits. MAX_LFS_FILESIZE is kernel
2856          * defined to the maximum the page cache page index can cope with
2857          * without overflowing the index or to 2^63 - 1, whichever is smaller.
2858          */
2859         sb->s_maxbytes = MAX_LFS_FILESIZE;
2860         /* Ntfs measures time in 100ns intervals. */
2861         sb->s_time_gran = 100;
2862         /*
2863          * Now load the metadata required for the page cache and our address
2864          * space operations to function. We do this by setting up a specialised
2865          * read_inode method and then just calling the normal iget() to obtain
2866          * the inode for $MFT which is sufficient to allow our normal inode
2867          * operations and associated address space operations to function.
2868          */
2869         sb->s_op = &ntfs_sops;
2870         tmp_ino = new_inode(sb);
2871         if (!tmp_ino) {
2872                 if (!silent)
2873                         ntfs_error(sb, "Failed to load essential metadata.");
2874                 goto err_out_now;
2875         }
2876         tmp_ino->i_ino = FILE_MFT;
2877         insert_inode_hash(tmp_ino);
2878         if (ntfs_read_inode_mount(tmp_ino) < 0) {
2879                 if (!silent)
2880                         ntfs_error(sb, "Failed to load essential metadata.");
2881                 goto iput_tmp_ino_err_out_now;
2882         }
2883         mutex_lock(&ntfs_lock);
2884         /*
2885          * The current mount is a compression user if the cluster size is
2886          * less than or equal 4kiB.
2887          */
2888         if (vol->cluster_size <= 4096 && !ntfs_nr_compression_users++) {
2889                 result = allocate_compression_buffers();
2890                 if (result) {
2891                         ntfs_error(NULL, "Failed to allocate buffers "
2892                                         "for compression engine.");
2893                         ntfs_nr_compression_users--;
2894                         mutex_unlock(&ntfs_lock);
2895                         goto iput_tmp_ino_err_out_now;
2896                 }
2897         }
2898         /*
2899          * Generate the global default upcase table if necessary.  Also
2900          * temporarily increment the number of upcase users to avoid race
2901          * conditions with concurrent (u)mounts.
2902          */
2903         if (!default_upcase)
2904                 default_upcase = generate_default_upcase();
2905         ntfs_nr_upcase_users++;
2906         mutex_unlock(&ntfs_lock);
2907         /*
2908          * From now on, ignore @silent parameter. If we fail below this line,
2909          * it will be due to a corrupt fs or a system error, so we report it.
2910          */
2911         /*
2912          * Open the system files with normal access functions and complete
2913          * setting up the ntfs super block.
2914          */
2915         if (!load_system_files(vol)) {
2916                 ntfs_error(sb, "Failed to load system files.");
2917                 goto unl_upcase_iput_tmp_ino_err_out_now;
2918         }
2919 
2920         /* We grab a reference, simulating an ntfs_iget(). */
2921         ihold(vol->root_ino);
2922         if ((sb->s_root = d_make_root(vol->root_ino))) {
2923                 ntfs_debug("Exiting, status successful.");
2924                 /* Release the default upcase if it has no users. */
2925                 mutex_lock(&ntfs_lock);
2926                 if (!--ntfs_nr_upcase_users && default_upcase) {
2927                         ntfs_free(default_upcase);
2928                         default_upcase = NULL;
2929                 }
2930                 mutex_unlock(&ntfs_lock);
2931                 sb->s_export_op = &ntfs_export_ops;
2932                 lockdep_on();
2933                 return 0;
2934         }
2935         ntfs_error(sb, "Failed to allocate root directory.");
2936         /* Clean up after the successful load_system_files() call from above. */
2937         // TODO: Use ntfs_put_super() instead of repeating all this code...
2938         // FIXME: Should mark the volume clean as the error is most likely
2939         //        -ENOMEM.
2940         iput(vol->vol_ino);
2941         vol->vol_ino = NULL;
2942         /* NTFS 3.0+ specific clean up. */
2943         if (vol->major_ver >= 3) {
2944 #ifdef NTFS_RW
2945                 if (vol->usnjrnl_j_ino) {
2946                         iput(vol->usnjrnl_j_ino);
2947                         vol->usnjrnl_j_ino = NULL;
2948                 }
2949                 if (vol->usnjrnl_max_ino) {
2950                         iput(vol->usnjrnl_max_ino);
2951                         vol->usnjrnl_max_ino = NULL;
2952                 }
2953                 if (vol->usnjrnl_ino) {
2954                         iput(vol->usnjrnl_ino);
2955                         vol->usnjrnl_ino = NULL;
2956                 }
2957                 if (vol->quota_q_ino) {
2958                         iput(vol->quota_q_ino);
2959                         vol->quota_q_ino = NULL;
2960                 }
2961                 if (vol->quota_ino) {
2962                         iput(vol->quota_ino);
2963                         vol->quota_ino = NULL;
2964                 }
2965 #endif /* NTFS_RW */
2966                 if (vol->extend_ino) {
2967                         iput(vol->extend_ino);
2968                         vol->extend_ino = NULL;
2969                 }
2970                 if (vol->secure_ino) {
2971                         iput(vol->secure_ino);
2972                         vol->secure_ino = NULL;
2973                 }
2974         }
2975         iput(vol->root_ino);
2976         vol->root_ino = NULL;
2977         iput(vol->lcnbmp_ino);
2978         vol->lcnbmp_ino = NULL;
2979         iput(vol->mftbmp_ino);
2980         vol->mftbmp_ino = NULL;
2981 #ifdef NTFS_RW
2982         if (vol->logfile_ino) {
2983                 iput(vol->logfile_ino);
2984                 vol->logfile_ino = NULL;
2985         }
2986         if (vol->mftmirr_ino) {
2987                 iput(vol->mftmirr_ino);
2988                 vol->mftmirr_ino = NULL;
2989         }
2990 #endif /* NTFS_RW */
2991         /* Throw away the table of attribute definitions. */
2992         vol->attrdef_size = 0;
2993         if (vol->attrdef) {
2994                 ntfs_free(vol->attrdef);
2995                 vol->attrdef = NULL;
2996         }
2997         vol->upcase_len = 0;
2998         mutex_lock(&ntfs_lock);
2999         if (vol->upcase == default_upcase) {
3000                 ntfs_nr_upcase_users--;
3001                 vol->upcase = NULL;
3002         }
3003         mutex_unlock(&ntfs_lock);
3004         if (vol->upcase) {
3005                 ntfs_free(vol->upcase);
3006                 vol->upcase = NULL;
3007         }
3008         if (vol->nls_map) {
3009                 unload_nls(vol->nls_map);
3010                 vol->nls_map = NULL;
3011         }
3012         /* Error exit code path. */
3013 unl_upcase_iput_tmp_ino_err_out_now:
3014         /*
3015          * Decrease the number of upcase users and destroy the global default
3016          * upcase table if necessary.
3017          */
3018         mutex_lock(&ntfs_lock);
3019         if (!--ntfs_nr_upcase_users && default_upcase) {
3020                 ntfs_free(default_upcase);
3021                 default_upcase = NULL;
3022         }
3023         if (vol->cluster_size <= 4096 && !--ntfs_nr_compression_users)
3024                 free_compression_buffers();
3025         mutex_unlock(&ntfs_lock);
3026 iput_tmp_ino_err_out_now:
3027         iput(tmp_ino);
3028         if (vol->mft_ino && vol->mft_ino != tmp_ino)
3029                 iput(vol->mft_ino);
3030         vol->mft_ino = NULL;
3031         /* Errors at this stage are irrelevant. */
3032 err_out_now:
3033         sb->s_fs_info = NULL;
3034         kfree(vol);
3035         ntfs_debug("Failed, returning -EINVAL.");
3036         lockdep_on();
3037         return -EINVAL;
3038 }
3039 
3040 /*
3041  * This is a slab cache to optimize allocations and deallocations of Unicode
3042  * strings of the maximum length allowed by NTFS, which is NTFS_MAX_NAME_LEN
3043  * (255) Unicode characters + a terminating NULL Unicode character.
3044  */
3045 struct kmem_cache *ntfs_name_cache;
3046 
3047 /* Slab caches for efficient allocation/deallocation of inodes. */
3048 struct kmem_cache *ntfs_inode_cache;
3049 struct kmem_cache *ntfs_big_inode_cache;
3050 
3051 /* Init once constructor for the inode slab cache. */
3052 static void ntfs_big_inode_init_once(void *foo)
3053 {
3054         ntfs_inode *ni = (ntfs_inode *)foo;
3055 
3056         inode_init_once(VFS_I(ni));
3057 }
3058 
3059 /*
3060  * Slab caches to optimize allocations and deallocations of attribute search
3061  * contexts and index contexts, respectively.
3062  */
3063 struct kmem_cache *ntfs_attr_ctx_cache;
3064 struct kmem_cache *ntfs_index_ctx_cache;
3065 
3066 /* Driver wide mutex. */
3067 DEFINE_MUTEX(ntfs_lock);
3068 
3069 static struct dentry *ntfs_mount(struct file_system_type *fs_type,
3070         int flags, const char *dev_name, void *data)
3071 {
3072         return mount_bdev(fs_type, flags, dev_name, data, ntfs_fill_super);
3073 }
3074 
3075 static struct file_system_type ntfs_fs_type = {
3076         .owner          = THIS_MODULE,
3077         .name           = "ntfs",
3078         .mount          = ntfs_mount,
3079         .kill_sb        = kill_block_super,
3080         .fs_flags       = FS_REQUIRES_DEV,
3081 };
3082 MODULE_ALIAS_FS("ntfs");
3083 
3084 /* Stable names for the slab caches. */
3085 static const char ntfs_index_ctx_cache_name[] = "ntfs_index_ctx_cache";
3086 static const char ntfs_attr_ctx_cache_name[] = "ntfs_attr_ctx_cache";
3087 static const char ntfs_name_cache_name[] = "ntfs_name_cache";
3088 static const char ntfs_inode_cache_name[] = "ntfs_inode_cache";
3089 static const char ntfs_big_inode_cache_name[] = "ntfs_big_inode_cache";
3090 
3091 static int __init init_ntfs_fs(void)
3092 {
3093         int err = 0;
3094 
3095         /* This may be ugly but it results in pretty output so who cares. (-8 */
3096         printk(KERN_INFO "NTFS driver " NTFS_VERSION " [Flags: R/"
3097 #ifdef NTFS_RW
3098                         "W"
3099 #else
3100                         "O"
3101 #endif
3102 #ifdef DEBUG
3103                         " DEBUG"
3104 #endif
3105 #ifdef MODULE
3106                         " MODULE"
3107 #endif
3108                         "].\n");
3109 
3110         ntfs_debug("Debug messages are enabled.");
3111 
3112         ntfs_index_ctx_cache = kmem_cache_create(ntfs_index_ctx_cache_name,
3113                         sizeof(ntfs_index_context), 0 /* offset */,
3114                         SLAB_HWCACHE_ALIGN, NULL /* ctor */);
3115         if (!ntfs_index_ctx_cache) {
3116                 printk(KERN_CRIT "NTFS: Failed to create %s!\n",
3117                                 ntfs_index_ctx_cache_name);
3118                 goto ictx_err_out;
3119         }
3120         ntfs_attr_ctx_cache = kmem_cache_create(ntfs_attr_ctx_cache_name,
3121                         sizeof(ntfs_attr_search_ctx), 0 /* offset */,
3122                         SLAB_HWCACHE_ALIGN, NULL /* ctor */);
3123         if (!ntfs_attr_ctx_cache) {
3124                 printk(KERN_CRIT "NTFS: Failed to create %s!\n",
3125                                 ntfs_attr_ctx_cache_name);
3126                 goto actx_err_out;
3127         }
3128 
3129         ntfs_name_cache = kmem_cache_create(ntfs_name_cache_name,
3130                         (NTFS_MAX_NAME_LEN+1) * sizeof(ntfschar), 0,
3131                         SLAB_HWCACHE_ALIGN, NULL);
3132         if (!ntfs_name_cache) {
3133                 printk(KERN_CRIT "NTFS: Failed to create %s!\n",
3134                                 ntfs_name_cache_name);
3135                 goto name_err_out;
3136         }
3137 
3138         ntfs_inode_cache = kmem_cache_create(ntfs_inode_cache_name,
3139                         sizeof(ntfs_inode), 0,
3140                         SLAB_RECLAIM_ACCOUNT|SLAB_MEM_SPREAD, NULL);
3141         if (!ntfs_inode_cache) {
3142                 printk(KERN_CRIT "NTFS: Failed to create %s!\n",
3143                                 ntfs_inode_cache_name);
3144                 goto inode_err_out;
3145         }
3146 
3147         ntfs_big_inode_cache = kmem_cache_create(ntfs_big_inode_cache_name,
3148                         sizeof(big_ntfs_inode), 0,
3149                         SLAB_HWCACHE_ALIGN|SLAB_RECLAIM_ACCOUNT|SLAB_MEM_SPREAD,
3150                         ntfs_big_inode_init_once);
3151         if (!ntfs_big_inode_cache) {
3152                 printk(KERN_CRIT "NTFS: Failed to create %s!\n",
3153                                 ntfs_big_inode_cache_name);
3154                 goto big_inode_err_out;
3155         }
3156 
3157         /* Register the ntfs sysctls. */
3158         err = ntfs_sysctl(1);
3159         if (err) {
3160                 printk(KERN_CRIT "NTFS: Failed to register NTFS sysctls!\n");
3161                 goto sysctl_err_out;
3162         }
3163 
3164         err = register_filesystem(&ntfs_fs_type);
3165         if (!err) {
3166                 ntfs_debug("NTFS driver registered successfully.");
3167                 return 0; /* Success! */
3168         }
3169         printk(KERN_CRIT "NTFS: Failed to register NTFS filesystem driver!\n");
3170 
3171         /* Unregister the ntfs sysctls. */
3172         ntfs_sysctl(0);
3173 sysctl_err_out:
3174         kmem_cache_destroy(ntfs_big_inode_cache);
3175 big_inode_err_out:
3176         kmem_cache_destroy(ntfs_inode_cache);
3177 inode_err_out:
3178         kmem_cache_destroy(ntfs_name_cache);
3179 name_err_out:
3180         kmem_cache_destroy(ntfs_attr_ctx_cache);
3181 actx_err_out:
3182         kmem_cache_destroy(ntfs_index_ctx_cache);
3183 ictx_err_out:
3184         if (!err) {
3185                 printk(KERN_CRIT "NTFS: Aborting NTFS filesystem driver "
3186                                 "registration...\n");
3187                 err = -ENOMEM;
3188         }
3189         return err;
3190 }
3191 
3192 static void __exit exit_ntfs_fs(void)
3193 {
3194         ntfs_debug("Unregistering NTFS driver.");
3195 
3196         unregister_filesystem(&ntfs_fs_type);
3197 
3198         /*
3199          * Make sure all delayed rcu free inodes are flushed before we
3200          * destroy cache.
3201          */
3202         rcu_barrier();
3203         kmem_cache_destroy(ntfs_big_inode_cache);
3204         kmem_cache_destroy(ntfs_inode_cache);
3205         kmem_cache_destroy(ntfs_name_cache);
3206         kmem_cache_destroy(ntfs_attr_ctx_cache);
3207         kmem_cache_destroy(ntfs_index_ctx_cache);
3208         /* Unregister the ntfs sysctls. */
3209         ntfs_sysctl(0);
3210 }
3211 
3212 MODULE_AUTHOR("Anton Altaparmakov <anton@tuxera.com>");
3213 MODULE_DESCRIPTION("NTFS 1.2/3.x driver - Copyright (c) 2001-2011 Anton Altaparmakov and Tuxera Inc.");
3214 MODULE_VERSION(NTFS_VERSION);
3215 MODULE_LICENSE("GPL");
3216 #ifdef DEBUG
3217 module_param(debug_msgs, bint, 0);
3218 MODULE_PARM_DESC(debug_msgs, "Enable debug messages.");
3219 #endif
3220 
3221 module_init(init_ntfs_fs)
3222 module_exit(exit_ntfs_fs)
3223 

~ [ source navigation ] ~ [ diff markup ] ~ [ identifier search ] ~

kernel.org | git.kernel.org | LWN.net | Project Home | Wiki (Japanese) | Wiki (English) | SVN repository | Mail admin

Linux® is a registered trademark of Linus Torvalds in the United States and other countries.
TOMOYO® is a registered trademark of NTT DATA CORPORATION.

osdn.jp