root/fs/ntfs/super.c

DEFINITIONS

1. simple_getbool
2. parse_options
3. ntfs_write_volume_flags
4. ntfs_set_volume_flags
5. ntfs_clear_volume_flags
6. ntfs_remount
7. is_boot_sector_ntfs
8. read_ntfs_boot_sector
9. parse_ntfs_boot_sector
10. ntfs_setup_allocators
11. load_and_init_mft_mirror
12. check_mft_mirror
13. load_and_check_logfile
14. check_windows_hibernation_status
15. load_and_init_quota
16. load_and_init_usnjrnl
17. load_and_init_attrdef
18. load_and_init_upcase
19. load_system_files
20. ntfs_put_super
21. get_nr_free_clusters
22. __get_nr_free_mft_records
23. ntfs_statfs
24. ntfs_write_inode
25. ntfs_fill_super
26. ntfs_big_inode_init_once
27. ntfs_mount
28. init_ntfs_fs
29. exit_ntfs_fs

   1 // SPDX-License-Identifier: GPL-2.0-or-later
   2 /*
   3  * super.c - NTFS kernel super block handling. Part of the Linux-NTFS project.
   4  *
   5  * Copyright (c) 2001-2012 Anton Altaparmakov and Tuxera Inc.
   6  * Copyright (c) 2001,2002 Richard Russon
   7  */
   8 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
   9 
  10 #include <linux/stddef.h>
  11 #include <linux/init.h>
  12 #include <linux/slab.h>
  13 #include <linux/string.h>
  14 #include <linux/spinlock.h>
  15 #include <linux/blkdev.h>       /* For bdev_logical_block_size(). */
  16 #include <linux/backing-dev.h>
  17 #include <linux/buffer_head.h>
  18 #include <linux/vfs.h>
  19 #include <linux/moduleparam.h>
  20 #include <linux/bitmap.h>
  21 
  22 #include "sysctl.h"
  23 #include "logfile.h"
  24 #include "quota.h"
  25 #include "usnjrnl.h"
  26 #include "dir.h"
  27 #include "debug.h"
  28 #include "index.h"
  29 #include "inode.h"
  30 #include "aops.h"
  31 #include "layout.h"
  32 #include "malloc.h"
  33 #include "ntfs.h"
  34 
  35 /* Number of mounted filesystems which have compression enabled. */
  36 static unsigned long ntfs_nr_compression_users;
  37 
  38 /* A global default upcase table and a corresponding reference count. */
  39 static ntfschar *default_upcase;
  40 static unsigned long ntfs_nr_upcase_users;
  41 
  42 /* Error constants/strings used in inode.c::ntfs_show_options(). */
  43 typedef enum {
  44         /* One of these must be present, default is ON_ERRORS_CONTINUE. */
  45         ON_ERRORS_PANIC                 = 0x01,
  46         ON_ERRORS_REMOUNT_RO            = 0x02,
  47         ON_ERRORS_CONTINUE              = 0x04,
  48         /* Optional, can be combined with any of the above. */
  49         ON_ERRORS_RECOVER               = 0x10,
  50 } ON_ERRORS_ACTIONS;
  51 
  52 const option_t on_errors_arr[] = {
  53         { ON_ERRORS_PANIC,      "panic" },
  54         { ON_ERRORS_REMOUNT_RO, "remount-ro", },
  55         { ON_ERRORS_CONTINUE,   "continue", },
  56         { ON_ERRORS_RECOVER,    "recover" },
  57         { 0,                    NULL }
  58 };
  59 
  60 /**
  61  * simple_getbool -
  62  *
  63  * Copied from old ntfs driver (which copied from vfat driver).
  64  */
  65 static int simple_getbool(char *s, bool *setval)
  66 {
  67         if (s) {
  68                 if (!strcmp(s, "1") || !strcmp(s, "yes") || !strcmp(s, "true"))
  69                         *setval = true;
  70                 else if (!strcmp(s, "0") || !strcmp(s, "no") ||
  71                                                         !strcmp(s, "false"))
  72                         *setval = false;
  73                 else
  74                         return 0;
  75         } else
  76                 *setval = true;
  77         return 1;
  78 }
  79 
  80 /**
  81  * parse_options - parse the (re)mount options
  82  * @vol:        ntfs volume
  83  * @opt:        string containing the (re)mount options
  84  *
  85  * Parse the recognized options in @opt for the ntfs volume described by @vol.
  86  */
  87 static bool parse_options(ntfs_volume *vol, char *opt)
  88 {
  89         char *p, *v, *ov;
  90         static char *utf8 = "utf8";
  91         int errors = 0, sloppy = 0;
  92         kuid_t uid = INVALID_UID;
  93         kgid_t gid = INVALID_GID;
  94         umode_t fmask = (umode_t)-1, dmask = (umode_t)-1;
  95         int mft_zone_multiplier = -1, on_errors = -1;
  96         int show_sys_files = -1, case_sensitive = -1, disable_sparse = -1;
  97         struct nls_table *nls_map = NULL, *old_nls;
  98 
  99         /* I am lazy... (-8 */
 100 #define NTFS_GETOPT_WITH_DEFAULT(option, variable, default_value)       \
 101         if (!strcmp(p, option)) {                                       \
 102                 if (!v || !*v)                                          \
 103                         variable = default_value;                       \
 104                 else {                                                  \
 105                         variable = simple_strtoul(ov = v, &v, 0);       \
 106                         if (*v)                                         \
 107                                 goto needs_val;                         \
 108                 }                                                       \
 109         }
 110 #define NTFS_GETOPT(option, variable)                                   \
 111         if (!strcmp(p, option)) {                                       \
 112                 if (!v || !*v)                                          \
 113                         goto needs_arg;                                 \
 114                 variable = simple_strtoul(ov = v, &v, 0);               \
 115                 if (*v)                                                 \
 116                         goto needs_val;                                 \
 117         }
 118 #define NTFS_GETOPT_UID(option, variable)                               \
 119         if (!strcmp(p, option)) {                                       \
 120                 uid_t uid_value;                                        \
 121                 if (!v || !*v)                                          \
 122                         goto needs_arg;                                 \
 123                 uid_value = simple_strtoul(ov = v, &v, 0);              \
 124                 if (*v)                                                 \
 125                         goto needs_val;                                 \
 126                 variable = make_kuid(current_user_ns(), uid_value);     \
 127                 if (!uid_valid(variable))                               \
 128                         goto needs_val;                                 \
 129         }
 130 #define NTFS_GETOPT_GID(option, variable)                               \
 131         if (!strcmp(p, option)) {                                       \
 132                 gid_t gid_value;                                        \
 133                 if (!v || !*v)                                          \
 134                         goto needs_arg;                                 \
 135                 gid_value = simple_strtoul(ov = v, &v, 0);              \
 136                 if (*v)                                                 \
 137                         goto needs_val;                                 \
 138                 variable = make_kgid(current_user_ns(), gid_value);     \
 139                 if (!gid_valid(variable))                               \
 140                         goto needs_val;                                 \
 141         }
 142 #define NTFS_GETOPT_OCTAL(option, variable)                             \
 143         if (!strcmp(p, option)) {                                       \
 144                 if (!v || !*v)                                          \
 145                         goto needs_arg;                                 \
 146                 variable = simple_strtoul(ov = v, &v, 8);               \
 147                 if (*v)                                                 \
 148                         goto needs_val;                                 \
 149         }
 150 #define NTFS_GETOPT_BOOL(option, variable)                              \
 151         if (!strcmp(p, option)) {                                       \
 152                 bool val;                                               \
 153                 if (!simple_getbool(v, &val))                           \
 154                         goto needs_bool;                                \
 155                 variable = val;                                         \
 156         }
 157 #define NTFS_GETOPT_OPTIONS_ARRAY(option, variable, opt_array)          \
 158         if (!strcmp(p, option)) {                                       \
 159                 int _i;                                                 \
 160                 if (!v || !*v)                                          \
 161                         goto needs_arg;                                 \
 162                 ov = v;                                                 \
 163                 if (variable == -1)                                     \
 164                         variable = 0;                                   \
 165                 for (_i = 0; opt_array[_i].str && *opt_array[_i].str; _i++) \
 166                         if (!strcmp(opt_array[_i].str, v)) {            \
 167                                 variable |= opt_array[_i].val;          \
 168                                 break;                                  \
 169                         }                                               \
 170                 if (!opt_array[_i].str || !*opt_array[_i].str)          \
 171                         goto needs_val;                                 \
 172         }
 173         if (!opt || !*opt)
 174                 goto no_mount_options;
 175         ntfs_debug("Entering with mount options string: %s", opt);
 176         while ((p = strsep(&opt, ","))) {
 177                 if ((v = strchr(p, '=')))
 178                         *v++ = 0;
 179                 NTFS_GETOPT_UID("uid", uid)
 180                 else NTFS_GETOPT_GID("gid", gid)
 181                 else NTFS_GETOPT_OCTAL("umask", fmask = dmask)
 182                 else NTFS_GETOPT_OCTAL("fmask", fmask)
 183                 else NTFS_GETOPT_OCTAL("dmask", dmask)
 184                 else NTFS_GETOPT("mft_zone_multiplier", mft_zone_multiplier)
 185                 else NTFS_GETOPT_WITH_DEFAULT("sloppy", sloppy, true)
 186                 else NTFS_GETOPT_BOOL("show_sys_files", show_sys_files)
 187                 else NTFS_GETOPT_BOOL("case_sensitive", case_sensitive)
 188                 else NTFS_GETOPT_BOOL("disable_sparse", disable_sparse)
 189                 else NTFS_GETOPT_OPTIONS_ARRAY("errors", on_errors,
 190                                 on_errors_arr)
 191                 else if (!strcmp(p, "posix") || !strcmp(p, "show_inodes"))
 192                         ntfs_warning(vol->sb, "Ignoring obsolete option %s.",
 193                                         p);
 194                 else if (!strcmp(p, "nls") || !strcmp(p, "iocharset")) {
 195                         if (!strcmp(p, "iocharset"))
 196                                 ntfs_warning(vol->sb, "Option iocharset is "
 197                                                 "deprecated. Please use "
 198                                                 "option nls=<charsetname> in "
 199                                                 "the future.");
 200                         if (!v || !*v)
 201                                 goto needs_arg;
 202 use_utf8:
 203                         old_nls = nls_map;
 204                         nls_map = load_nls(v);
 205                         if (!nls_map) {
 206                                 if (!old_nls) {
 207                                         ntfs_error(vol->sb, "NLS character set "
 208                                                         "%s not found.", v);
 209                                         return false;
 210                                 }
 211                                 ntfs_error(vol->sb, "NLS character set %s not "
 212                                                 "found. Using previous one %s.",
 213                                                 v, old_nls->charset);
 214                                 nls_map = old_nls;
 215                         } else /* nls_map */ {
 216                                 unload_nls(old_nls);
 217                         }
 218                 } else if (!strcmp(p, "utf8")) {
 219                         bool val = false;
 220                         ntfs_warning(vol->sb, "Option utf8 is no longer "
 221                                    "supported, using option nls=utf8. Please "
 222                                    "use option nls=utf8 in the future and "
 223                                    "make sure utf8 is compiled either as a "
 224                                    "module or into the kernel.");
 225                         if (!v || !*v)
 226                                 val = true;
 227                         else if (!simple_getbool(v, &val))
 228                                 goto needs_bool;
 229                         if (val) {
 230                                 v = utf8;
 231                                 goto use_utf8;
 232                         }
 233                 } else {
 234                         ntfs_error(vol->sb, "Unrecognized mount option %s.", p);
 235                         if (errors < INT_MAX)
 236                                 errors++;
 237                 }
 238 #undef NTFS_GETOPT_OPTIONS_ARRAY
 239 #undef NTFS_GETOPT_BOOL
 240 #undef NTFS_GETOPT
 241 #undef NTFS_GETOPT_WITH_DEFAULT
 242         }
 243 no_mount_options:
 244         if (errors && !sloppy)
 245                 return false;
 246         if (sloppy)
 247                 ntfs_warning(vol->sb, "Sloppy option given. Ignoring "
 248                                 "unrecognized mount option(s) and continuing.");
 249         /* Keep this first! */
 250         if (on_errors != -1) {
 251                 if (!on_errors) {
 252                         ntfs_error(vol->sb, "Invalid errors option argument "
 253                                         "or bug in options parser.");
 254                         return false;
 255                 }
 256         }
 257         if (nls_map) {
 258                 if (vol->nls_map && vol->nls_map != nls_map) {
 259                         ntfs_error(vol->sb, "Cannot change NLS character set "
 260                                         "on remount.");
 261                         return false;
 262                 } /* else (!vol->nls_map) */
 263                 ntfs_debug("Using NLS character set %s.", nls_map->charset);
 264                 vol->nls_map = nls_map;
 265         } else /* (!nls_map) */ {
 266                 if (!vol->nls_map) {
 267                         vol->nls_map = load_nls_default();
 268                         if (!vol->nls_map) {
 269                                 ntfs_error(vol->sb, "Failed to load default "
 270                                                 "NLS character set.");
 271                                 return false;
 272                         }
 273                         ntfs_debug("Using default NLS character set (%s).",
 274                                         vol->nls_map->charset);
 275                 }
 276         }
 277         if (mft_zone_multiplier != -1) {
 278                 if (vol->mft_zone_multiplier && vol->mft_zone_multiplier !=
 279                                 mft_zone_multiplier) {
 280                         ntfs_error(vol->sb, "Cannot change mft_zone_multiplier "
 281                                         "on remount.");
 282                         return false;
 283                 }
 284                 if (mft_zone_multiplier < 1 || mft_zone_multiplier > 4) {
 285                         ntfs_error(vol->sb, "Invalid mft_zone_multiplier. "
 286                                         "Using default value, i.e. 1.");
 287                         mft_zone_multiplier = 1;
 288                 }
 289                 vol->mft_zone_multiplier = mft_zone_multiplier;
 290         }
 291         if (!vol->mft_zone_multiplier)
 292                 vol->mft_zone_multiplier = 1;
 293         if (on_errors != -1)
 294                 vol->on_errors = on_errors;
 295         if (!vol->on_errors || vol->on_errors == ON_ERRORS_RECOVER)
 296                 vol->on_errors |= ON_ERRORS_CONTINUE;
 297         if (uid_valid(uid))
 298                 vol->uid = uid;
 299         if (gid_valid(gid))
 300                 vol->gid = gid;
 301         if (fmask != (umode_t)-1)
 302                 vol->fmask = fmask;
 303         if (dmask != (umode_t)-1)
 304                 vol->dmask = dmask;
 305         if (show_sys_files != -1) {
 306                 if (show_sys_files)
 307                         NVolSetShowSystemFiles(vol);
 308                 else
 309                         NVolClearShowSystemFiles(vol);
 310         }
 311         if (case_sensitive != -1) {
 312                 if (case_sensitive)
 313                         NVolSetCaseSensitive(vol);
 314                 else
 315                         NVolClearCaseSensitive(vol);
 316         }
 317         if (disable_sparse != -1) {
 318                 if (disable_sparse)
 319                         NVolClearSparseEnabled(vol);
 320                 else {
 321                         if (!NVolSparseEnabled(vol) &&
 322                                         vol->major_ver && vol->major_ver < 3)
 323                                 ntfs_warning(vol->sb, "Not enabling sparse "
 324                                                 "support due to NTFS volume "
 325                                                 "version %i.%i (need at least "
 326                                                 "version 3.0).", vol->major_ver,
 327                                                 vol->minor_ver);
 328                         else
 329                                 NVolSetSparseEnabled(vol);
 330                 }
 331         }
 332         return true;
 333 needs_arg:
 334         ntfs_error(vol->sb, "The %s option requires an argument.", p);
 335         return false;
 336 needs_bool:
 337         ntfs_error(vol->sb, "The %s option requires a boolean argument.", p);
 338         return false;
 339 needs_val:
 340         ntfs_error(vol->sb, "Invalid %s option argument: %s", p, ov);
 341         return false;
 342 }
 343 
 344 #ifdef NTFS_RW
 345 
 346 /**
 347  * ntfs_write_volume_flags - write new flags to the volume information flags
 348  * @vol:        ntfs volume on which to modify the flags
 349  * @flags:      new flags value for the volume information flags
 350  *
 351  * Internal function.  You probably want to use ntfs_{set,clear}_volume_flags()
 352  * instead (see below).
 353  *
 354  * Replace the volume information flags on the volume @vol with the value
 355  * supplied in @flags.  Note, this overwrites the volume information flags, so
 356  * make sure to combine the flags you want to modify with the old flags and use
 357  * the result when calling ntfs_write_volume_flags().
 358  *
 359  * Return 0 on success and -errno on error.
 360  */
 361 static int ntfs_write_volume_flags(ntfs_volume *vol, const VOLUME_FLAGS flags)
 362 {
 363         ntfs_inode *ni = NTFS_I(vol->vol_ino);
 364         MFT_RECORD *m;
 365         VOLUME_INFORMATION *vi;
 366         ntfs_attr_search_ctx *ctx;
 367         int err;
 368 
 369         ntfs_debug("Entering, old flags = 0x%x, new flags = 0x%x.",
 370                         le16_to_cpu(vol->vol_flags), le16_to_cpu(flags));
 371         if (vol->vol_flags == flags)
 372                 goto done;
 373         BUG_ON(!ni);
 374         m = map_mft_record(ni);
 375         if (IS_ERR(m)) {
 376                 err = PTR_ERR(m);
 377                 goto err_out;
 378         }
 379         ctx = ntfs_attr_get_search_ctx(ni, m);
 380         if (!ctx) {
 381                 err = -ENOMEM;
 382                 goto put_unm_err_out;
 383         }
 384         err = ntfs_attr_lookup(AT_VOLUME_INFORMATION, NULL, 0, 0, 0, NULL, 0,
 385                         ctx);
 386         if (err)
 387                 goto put_unm_err_out;
 388         vi = (VOLUME_INFORMATION*)((u8*)ctx->attr +
 389                         le16_to_cpu(ctx->attr->data.resident.value_offset));
 390         vol->vol_flags = vi->flags = flags;
 391         flush_dcache_mft_record_page(ctx->ntfs_ino);
 392         mark_mft_record_dirty(ctx->ntfs_ino);
 393         ntfs_attr_put_search_ctx(ctx);
 394         unmap_mft_record(ni);
 395 done:
 396         ntfs_debug("Done.");
 397         return 0;
 398 put_unm_err_out:
 399         if (ctx)
 400                 ntfs_attr_put_search_ctx(ctx);
 401         unmap_mft_record(ni);
 402 err_out:
 403         ntfs_error(vol->sb, "Failed with error code %i.", -err);
 404         return err;
 405 }
 406 
 407 /**
 408  * ntfs_set_volume_flags - set bits in the volume information flags
 409  * @vol:        ntfs volume on which to modify the flags
 410  * @flags:      flags to set on the volume
 411  *
 412  * Set the bits in @flags in the volume information flags on the volume @vol.
 413  *
 414  * Return 0 on success and -errno on error.
 415  */
 416 static inline int ntfs_set_volume_flags(ntfs_volume *vol, VOLUME_FLAGS flags)
 417 {
 418         flags &= VOLUME_FLAGS_MASK;
 419         return ntfs_write_volume_flags(vol, vol->vol_flags | flags);
 420 }
 421 
 422 /**
 423  * ntfs_clear_volume_flags - clear bits in the volume information flags
 424  * @vol:        ntfs volume on which to modify the flags
 425  * @flags:      flags to clear on the volume
 426  *
 427  * Clear the bits in @flags in the volume information flags on the volume @vol.
 428  *
 429  * Return 0 on success and -errno on error.
 430  */
 431 static inline int ntfs_clear_volume_flags(ntfs_volume *vol, VOLUME_FLAGS flags)
 432 {
 433         flags &= VOLUME_FLAGS_MASK;
 434         flags = vol->vol_flags & cpu_to_le16(~le16_to_cpu(flags));
 435         return ntfs_write_volume_flags(vol, flags);
 436 }
 437 
 438 #endif /* NTFS_RW */
 439 
 440 /**
 441  * ntfs_remount - change the mount options of a mounted ntfs filesystem
 442  * @sb:         superblock of mounted ntfs filesystem
 443  * @flags:      remount flags
 444  * @opt:        remount options string
 445  *
 446  * Change the mount options of an already mounted ntfs filesystem.
 447  *
 448  * NOTE:  The VFS sets the @sb->s_flags remount flags to @flags after
 449  * ntfs_remount() returns successfully (i.e. returns 0).  Otherwise,
 450  * @sb->s_flags are not changed.
 451  */
 452 static int ntfs_remount(struct super_block *sb, int *flags, char *opt)
 453 {
 454         ntfs_volume *vol = NTFS_SB(sb);
 455 
 456         ntfs_debug("Entering with remount options string: %s", opt);
 457 
 458         sync_filesystem(sb);
 459 
 460 #ifndef NTFS_RW
 461         /* For read-only compiled driver, enforce read-only flag. */
 462         *flags |= SB_RDONLY;
 463 #else /* NTFS_RW */
 464         /*
 465          * For the read-write compiled driver, if we are remounting read-write,
 466          * make sure there are no volume errors and that no unsupported volume
 467          * flags are set.  Also, empty the logfile journal as it would become
 468          * stale as soon as something is written to the volume and mark the
 469          * volume dirty so that chkdsk is run if the volume is not umounted
 470          * cleanly.  Finally, mark the quotas out of date so Windows rescans
 471          * the volume on boot and updates them.
 472          *
 473          * When remounting read-only, mark the volume clean if no volume errors
 474          * have occurred.
 475          */
 476         if (sb_rdonly(sb) && !(*flags & SB_RDONLY)) {
 477                 static const char *es = ".  Cannot remount read-write.";
 478 
 479                 /* Remounting read-write. */
 480                 if (NVolErrors(vol)) {
 481                         ntfs_error(sb, "Volume has errors and is read-only%s",
 482                                         es);
 483                         return -EROFS;
 484                 }
 485                 if (vol->vol_flags & VOLUME_IS_DIRTY) {
 486                         ntfs_error(sb, "Volume is dirty and read-only%s", es);
 487                         return -EROFS;
 488                 }
 489                 if (vol->vol_flags & VOLUME_MODIFIED_BY_CHKDSK) {
 490                         ntfs_error(sb, "Volume has been modified by chkdsk "
 491                                         "and is read-only%s", es);
 492                         return -EROFS;
 493                 }
 494                 if (vol->vol_flags & VOLUME_MUST_MOUNT_RO_MASK) {
 495                         ntfs_error(sb, "Volume has unsupported flags set "
 496                                         "(0x%x) and is read-only%s",
 497                                         (unsigned)le16_to_cpu(vol->vol_flags),
 498                                         es);
 499                         return -EROFS;
 500                 }
 501                 if (ntfs_set_volume_flags(vol, VOLUME_IS_DIRTY)) {
 502                         ntfs_error(sb, "Failed to set dirty bit in volume "
 503                                         "information flags%s", es);
 504                         return -EROFS;
 505                 }
 506 #if 0
 507                 // TODO: Enable this code once we start modifying anything that
 508                 //       is different between NTFS 1.2 and 3.x...
 509                 /* Set NT4 compatibility flag on newer NTFS version volumes. */
 510                 if ((vol->major_ver > 1)) {
 511                         if (ntfs_set_volume_flags(vol, VOLUME_MOUNTED_ON_NT4)) {
 512                                 ntfs_error(sb, "Failed to set NT4 "
 513                                                 "compatibility flag%s", es);
 514                                 NVolSetErrors(vol);
 515                                 return -EROFS;
 516                         }
 517                 }
 518 #endif
 519                 if (!ntfs_empty_logfile(vol->logfile_ino)) {
 520                         ntfs_error(sb, "Failed to empty journal $LogFile%s",
 521                                         es);
 522                         NVolSetErrors(vol);
 523                         return -EROFS;
 524                 }
 525                 if (!ntfs_mark_quotas_out_of_date(vol)) {
 526                         ntfs_error(sb, "Failed to mark quotas out of date%s",
 527                                         es);
 528                         NVolSetErrors(vol);
 529                         return -EROFS;
 530                 }
 531                 if (!ntfs_stamp_usnjrnl(vol)) {
 532                         ntfs_error(sb, "Failed to stamp transaction log "
 533                                         "($UsnJrnl)%s", es);
 534                         NVolSetErrors(vol);
 535                         return -EROFS;
 536                 }
 537         } else if (!sb_rdonly(sb) && (*flags & SB_RDONLY)) {
 538                 /* Remounting read-only. */
 539                 if (!NVolErrors(vol)) {
 540                         if (ntfs_clear_volume_flags(vol, VOLUME_IS_DIRTY))
 541                                 ntfs_warning(sb, "Failed to clear dirty bit "
 542                                                 "in volume information "
 543                                                 "flags.  Run chkdsk.");
 544                 }
 545         }
 546 #endif /* NTFS_RW */
 547 
 548         // TODO: Deal with *flags.
 549 
 550         if (!parse_options(vol, opt))
 551                 return -EINVAL;
 552 
 553         ntfs_debug("Done.");
 554         return 0;
 555 }
 556 
 557 /**
 558  * is_boot_sector_ntfs - check whether a boot sector is a valid NTFS boot sector
 559  * @sb:         Super block of the device to which @b belongs.
 560  * @b:          Boot sector of device @sb to check.
 561  * @silent:     If 'true', all output will be silenced.
 562  *
 563  * is_boot_sector_ntfs() checks whether the boot sector @b is a valid NTFS boot
 564  * sector. Returns 'true' if it is valid and 'false' if not.
 565  *
 566  * @sb is only needed for warning/error output, i.e. it can be NULL when silent
 567  * is 'true'.
 568  */
 569 static bool is_boot_sector_ntfs(const struct super_block *sb,
 570                 const NTFS_BOOT_SECTOR *b, const bool silent)
 571 {
 572         /*
 573          * Check that checksum == sum of u32 values from b to the checksum
 574          * field.  If checksum is zero, no checking is done.  We will work when
 575          * the checksum test fails, since some utilities update the boot sector
 576          * ignoring the checksum which leaves the checksum out-of-date.  We
 577          * report a warning if this is the case.
 578          */
 579         if ((void*)b < (void*)&b->checksum && b->checksum && !silent) {
 580                 le32 *u;
 581                 u32 i;
 582 
 583                 for (i = 0, u = (le32*)b; u < (le32*)(&b->checksum); ++u)
 584                         i += le32_to_cpup(u);
 585                 if (le32_to_cpu(b->checksum) != i)
 586                         ntfs_warning(sb, "Invalid boot sector checksum.");
 587         }
 588         /* Check OEMidentifier is "NTFS    " */
 589         if (b->oem_id != magicNTFS)
 590                 goto not_ntfs;
 591         /* Check bytes per sector value is between 256 and 4096. */
 592         if (le16_to_cpu(b->bpb.bytes_per_sector) < 0x100 ||
 593                         le16_to_cpu(b->bpb.bytes_per_sector) > 0x1000)
 594                 goto not_ntfs;
 595         /* Check sectors per cluster value is valid. */
 596         switch (b->bpb.sectors_per_cluster) {
 597         case 1: case 2: case 4: case 8: case 16: case 32: case 64: case 128:
 598                 break;
 599         default:
 600                 goto not_ntfs;
 601         }
 602         /* Check the cluster size is not above the maximum (64kiB). */
 603         if ((u32)le16_to_cpu(b->bpb.bytes_per_sector) *
 604                         b->bpb.sectors_per_cluster > NTFS_MAX_CLUSTER_SIZE)
 605                 goto not_ntfs;
 606         /* Check reserved/unused fields are really zero. */
 607         if (le16_to_cpu(b->bpb.reserved_sectors) ||
 608                         le16_to_cpu(b->bpb.root_entries) ||
 609                         le16_to_cpu(b->bpb.sectors) ||
 610                         le16_to_cpu(b->bpb.sectors_per_fat) ||
 611                         le32_to_cpu(b->bpb.large_sectors) || b->bpb.fats)
 612                 goto not_ntfs;
 613         /* Check clusters per file mft record value is valid. */
 614         if ((u8)b->clusters_per_mft_record < 0xe1 ||
 615                         (u8)b->clusters_per_mft_record > 0xf7)
 616                 switch (b->clusters_per_mft_record) {
 617                 case 1: case 2: case 4: case 8: case 16: case 32: case 64:
 618                         break;
 619                 default:
 620                         goto not_ntfs;
 621                 }
 622         /* Check clusters per index block value is valid. */
 623         if ((u8)b->clusters_per_index_record < 0xe1 ||
 624                         (u8)b->clusters_per_index_record > 0xf7)
 625                 switch (b->clusters_per_index_record) {
 626                 case 1: case 2: case 4: case 8: case 16: case 32: case 64:
 627                         break;
 628                 default:
 629                         goto not_ntfs;
 630                 }
 631         /*
 632          * Check for valid end of sector marker. We will work without it, but
 633          * many BIOSes will refuse to boot from a bootsector if the magic is
 634          * incorrect, so we emit a warning.
 635          */
 636         if (!silent && b->end_of_sector_marker != cpu_to_le16(0xaa55))
 637                 ntfs_warning(sb, "Invalid end of sector marker.");
 638         return true;
 639 not_ntfs:
 640         return false;
 641 }
 642 
 643 /**
 644  * read_ntfs_boot_sector - read the NTFS boot sector of a device
 645  * @sb:         super block of device to read the boot sector from
 646  * @silent:     if true, suppress all output
 647  *
 648  * Reads the boot sector from the device and validates it. If that fails, tries
 649  * to read the backup boot sector, first from the end of the device a-la NT4 and
 650  * later and then from the middle of the device a-la NT3.51 and before.
 651  *
 652  * If a valid boot sector is found but it is not the primary boot sector, we
 653  * repair the primary boot sector silently (unless the device is read-only or
 654  * the primary boot sector is not accessible).
 655  *
 656  * NOTE: To call this function, @sb must have the fields s_dev, the ntfs super
 657  * block (u.ntfs_sb), nr_blocks and the device flags (s_flags) initialized
 658  * to their respective values.
 659  *
 660  * Return the unlocked buffer head containing the boot sector or NULL on error.
 661  */
 662 static struct buffer_head *read_ntfs_boot_sector(struct super_block *sb,
 663                 const int silent)
 664 {
 665         const char *read_err_str = "Unable to read %s boot sector.";
 666         struct buffer_head *bh_primary, *bh_backup;
 667         sector_t nr_blocks = NTFS_SB(sb)->nr_blocks;
 668 
 669         /* Try to read primary boot sector. */
 670         if ((bh_primary = sb_bread(sb, 0))) {
 671                 if (is_boot_sector_ntfs(sb, (NTFS_BOOT_SECTOR*)
 672                                 bh_primary->b_data, silent))
 673                         return bh_primary;
 674                 if (!silent)
 675                         ntfs_error(sb, "Primary boot sector is invalid.");
 676         } else if (!silent)
 677                 ntfs_error(sb, read_err_str, "primary");
 678         if (!(NTFS_SB(sb)->on_errors & ON_ERRORS_RECOVER)) {
 679                 if (bh_primary)
 680                         brelse(bh_primary);
 681                 if (!silent)
 682                         ntfs_error(sb, "Mount option errors=recover not used. "
 683                                         "Aborting without trying to recover.");
 684                 return NULL;
 685         }
 686         /* Try to read NT4+ backup boot sector. */
 687         if ((bh_backup = sb_bread(sb, nr_blocks - 1))) {
 688                 if (is_boot_sector_ntfs(sb, (NTFS_BOOT_SECTOR*)
 689                                 bh_backup->b_data, silent))
 690                         goto hotfix_primary_boot_sector;
 691                 brelse(bh_backup);
 692         } else if (!silent)
 693                 ntfs_error(sb, read_err_str, "backup");
 694         /* Try to read NT3.51- backup boot sector. */
 695         if ((bh_backup = sb_bread(sb, nr_blocks >> 1))) {
 696                 if (is_boot_sector_ntfs(sb, (NTFS_BOOT_SECTOR*)
 697                                 bh_backup->b_data, silent))
 698                         goto hotfix_primary_boot_sector;
 699                 if (!silent)
 700                         ntfs_error(sb, "Could not find a valid backup boot "
 701                                         "sector.");
 702                 brelse(bh_backup);
 703         } else if (!silent)
 704                 ntfs_error(sb, read_err_str, "backup");
 705         /* We failed. Cleanup and return. */
 706         if (bh_primary)
 707                 brelse(bh_primary);
 708         return NULL;
 709 hotfix_primary_boot_sector:
 710         if (bh_primary) {
 711                 /*
 712                  * If we managed to read sector zero and the volume is not
 713                  * read-only, copy the found, valid backup boot sector to the
 714                  * primary boot sector.  Note we only copy the actual boot
 715                  * sector structure, not the actual whole device sector as that
 716                  * may be bigger and would potentially damage the $Boot system
 717                  * file (FIXME: Would be nice to know if the backup boot sector
 718                  * on a large sector device contains the whole boot loader or
 719                  * just the first 512 bytes).
 720                  */
 721                 if (!sb_rdonly(sb)) {
 722                         ntfs_warning(sb, "Hot-fix: Recovering invalid primary "
 723                                         "boot sector from backup copy.");
 724                         memcpy(bh_primary->b_data, bh_backup->b_data,
 725                                         NTFS_BLOCK_SIZE);
 726                         mark_buffer_dirty(bh_primary);
 727                         sync_dirty_buffer(bh_primary);
 728                         if (buffer_uptodate(bh_primary)) {
 729                                 brelse(bh_backup);
 730                                 return bh_primary;
 731                         }
 732                         ntfs_error(sb, "Hot-fix: Device write error while "
 733                                         "recovering primary boot sector.");
 734                 } else {
 735                         ntfs_warning(sb, "Hot-fix: Recovery of primary boot "
 736                                         "sector failed: Read-only mount.");
 737                 }
 738                 brelse(bh_primary);
 739         }
 740         ntfs_warning(sb, "Using backup boot sector.");
 741         return bh_backup;
 742 }
 743 
 744 /**
 745  * parse_ntfs_boot_sector - parse the boot sector and store the data in @vol
 746  * @vol:        volume structure to initialise with data from boot sector
 747  * @b:          boot sector to parse
 748  *
 749  * Parse the ntfs boot sector @b and store all imporant information therein in
 750  * the ntfs super block @vol.  Return 'true' on success and 'false' on error.
 751  */
 752 static bool parse_ntfs_boot_sector(ntfs_volume *vol, const NTFS_BOOT_SECTOR *b)
 753 {
 754         unsigned int sectors_per_cluster_bits, nr_hidden_sects;
 755         int clusters_per_mft_record, clusters_per_index_record;
 756         s64 ll;
 757 
 758         vol->sector_size = le16_to_cpu(b->bpb.bytes_per_sector);
 759         vol->sector_size_bits = ffs(vol->sector_size) - 1;
 760         ntfs_debug("vol->sector_size = %i (0x%x)", vol->sector_size,
 761                         vol->sector_size);
 762         ntfs_debug("vol->sector_size_bits = %i (0x%x)", vol->sector_size_bits,
 763                         vol->sector_size_bits);
 764         if (vol->sector_size < vol->sb->s_blocksize) {
 765                 ntfs_error(vol->sb, "Sector size (%i) is smaller than the "
 766                                 "device block size (%lu).  This is not "
 767                                 "supported.  Sorry.", vol->sector_size,
 768                                 vol->sb->s_blocksize);
 769                 return false;
 770         }
 771         ntfs_debug("sectors_per_cluster = 0x%x", b->bpb.sectors_per_cluster);
 772         sectors_per_cluster_bits = ffs(b->bpb.sectors_per_cluster) - 1;
 773         ntfs_debug("sectors_per_cluster_bits = 0x%x",
 774                         sectors_per_cluster_bits);
 775         nr_hidden_sects = le32_to_cpu(b->bpb.hidden_sectors);
 776         ntfs_debug("number of hidden sectors = 0x%x", nr_hidden_sects);
 777         vol->cluster_size = vol->sector_size << sectors_per_cluster_bits;
 778         vol->cluster_size_mask = vol->cluster_size - 1;
 779         vol->cluster_size_bits = ffs(vol->cluster_size) - 1;
 780         ntfs_debug("vol->cluster_size = %i (0x%x)", vol->cluster_size,
 781                         vol->cluster_size);
 782         ntfs_debug("vol->cluster_size_mask = 0x%x", vol->cluster_size_mask);
 783         ntfs_debug("vol->cluster_size_bits = %i", vol->cluster_size_bits);
 784         if (vol->cluster_size < vol->sector_size) {
 785                 ntfs_error(vol->sb, "Cluster size (%i) is smaller than the "
 786                                 "sector size (%i).  This is not supported.  "
 787                                 "Sorry.", vol->cluster_size, vol->sector_size);
 788                 return false;
 789         }
 790         clusters_per_mft_record = b->clusters_per_mft_record;
 791         ntfs_debug("clusters_per_mft_record = %i (0x%x)",
 792                         clusters_per_mft_record, clusters_per_mft_record);
 793         if (clusters_per_mft_record > 0)
 794                 vol->mft_record_size = vol->cluster_size <<
 795                                 (ffs(clusters_per_mft_record) - 1);
 796         else
 797                 /*
 798                  * When mft_record_size < cluster_size, clusters_per_mft_record
 799                  * = -log2(mft_record_size) bytes. mft_record_size normaly is
 800                  * 1024 bytes, which is encoded as 0xF6 (-10 in decimal).
 801                  */
 802                 vol->mft_record_size = 1 << -clusters_per_mft_record;
 803         vol->mft_record_size_mask = vol->mft_record_size - 1;
 804         vol->mft_record_size_bits = ffs(vol->mft_record_size) - 1;
 805         ntfs_debug("vol->mft_record_size = %i (0x%x)", vol->mft_record_size,
 806                         vol->mft_record_size);
 807         ntfs_debug("vol->mft_record_size_mask = 0x%x",
 808                         vol->mft_record_size_mask);
 809         ntfs_debug("vol->mft_record_size_bits = %i (0x%x)",
 810                         vol->mft_record_size_bits, vol->mft_record_size_bits);
 811         /*
 812          * We cannot support mft record sizes above the PAGE_SIZE since
 813          * we store $MFT/$DATA, the table of mft records in the page cache.
 814          */
 815         if (vol->mft_record_size > PAGE_SIZE) {
 816                 ntfs_error(vol->sb, "Mft record size (%i) exceeds the "
 817                                 "PAGE_SIZE on your system (%lu).  "
 818                                 "This is not supported.  Sorry.",
 819                                 vol->mft_record_size, PAGE_SIZE);
 820                 return false;
 821         }
 822         /* We cannot support mft record sizes below the sector size. */
 823         if (vol->mft_record_size < vol->sector_size) {
 824                 ntfs_error(vol->sb, "Mft record size (%i) is smaller than the "
 825                                 "sector size (%i).  This is not supported.  "
 826                                 "Sorry.", vol->mft_record_size,
 827                                 vol->sector_size);
 828                 return false;
 829         }
 830         clusters_per_index_record = b->clusters_per_index_record;
 831         ntfs_debug("clusters_per_index_record = %i (0x%x)",
 832                         clusters_per_index_record, clusters_per_index_record);
 833         if (clusters_per_index_record > 0)
 834                 vol->index_record_size = vol->cluster_size <<
 835                                 (ffs(clusters_per_index_record) - 1);
 836         else
 837                 /*
 838                  * When index_record_size < cluster_size,
 839                  * clusters_per_index_record = -log2(index_record_size) bytes.
 840                  * index_record_size normaly equals 4096 bytes, which is
 841                  * encoded as 0xF4 (-12 in decimal).
 842                  */
 843                 vol->index_record_size = 1 << -clusters_per_index_record;
 844         vol->index_record_size_mask = vol->index_record_size - 1;
 845         vol->index_record_size_bits = ffs(vol->index_record_size) - 1;
 846         ntfs_debug("vol->index_record_size = %i (0x%x)",
 847                         vol->index_record_size, vol->index_record_size);
 848         ntfs_debug("vol->index_record_size_mask = 0x%x",
 849                         vol->index_record_size_mask);
 850         ntfs_debug("vol->index_record_size_bits = %i (0x%x)",
 851                         vol->index_record_size_bits,
 852                         vol->index_record_size_bits);
 853         /* We cannot support index record sizes below the sector size. */
 854         if (vol->index_record_size < vol->sector_size) {
 855                 ntfs_error(vol->sb, "Index record size (%i) is smaller than "
 856                                 "the sector size (%i).  This is not "
 857                                 "supported.  Sorry.", vol->index_record_size,
 858                                 vol->sector_size);
 859                 return false;
 860         }
 861         /*
 862          * Get the size of the volume in clusters and check for 64-bit-ness.
 863          * Windows currently only uses 32 bits to save the clusters so we do
 864          * the same as it is much faster on 32-bit CPUs.
 865          */
 866         ll = sle64_to_cpu(b->number_of_sectors) >> sectors_per_cluster_bits;
 867         if ((u64)ll >= 1ULL << 32) {
 868                 ntfs_error(vol->sb, "Cannot handle 64-bit clusters.  Sorry.");
 869                 return false;
 870         }
 871         vol->nr_clusters = ll;
 872         ntfs_debug("vol->nr_clusters = 0x%llx", (long long)vol->nr_clusters);
 873         /*
 874          * On an architecture where unsigned long is 32-bits, we restrict the
 875          * volume size to 2TiB (2^41). On a 64-bit architecture, the compiler
 876          * will hopefully optimize the whole check away.
 877          */
 878         if (sizeof(unsigned long) < 8) {
 879                 if ((ll << vol->cluster_size_bits) >= (1ULL << 41)) {
 880                         ntfs_error(vol->sb, "Volume size (%lluTiB) is too "
 881                                         "large for this architecture.  "
 882                                         "Maximum supported is 2TiB.  Sorry.",
 883                                         (unsigned long long)ll >> (40 -
 884                                         vol->cluster_size_bits));
 885                         return false;
 886                 }
 887         }
 888         ll = sle64_to_cpu(b->mft_lcn);
 889         if (ll >= vol->nr_clusters) {
 890                 ntfs_error(vol->sb, "MFT LCN (%lli, 0x%llx) is beyond end of "
 891                                 "volume.  Weird.", (unsigned long long)ll,
 892                                 (unsigned long long)ll);
 893                 return false;
 894         }
 895         vol->mft_lcn = ll;
 896         ntfs_debug("vol->mft_lcn = 0x%llx", (long long)vol->mft_lcn);
 897         ll = sle64_to_cpu(b->mftmirr_lcn);
 898         if (ll >= vol->nr_clusters) {
 899                 ntfs_error(vol->sb, "MFTMirr LCN (%lli, 0x%llx) is beyond end "
 900                                 "of volume.  Weird.", (unsigned long long)ll,
 901                                 (unsigned long long)ll);
 902                 return false;
 903         }
 904         vol->mftmirr_lcn = ll;
 905         ntfs_debug("vol->mftmirr_lcn = 0x%llx", (long long)vol->mftmirr_lcn);
 906 #ifdef NTFS_RW
 907         /*
 908          * Work out the size of the mft mirror in number of mft records. If the
 909          * cluster size is less than or equal to the size taken by four mft
 910          * records, the mft mirror stores the first four mft records. If the
 911          * cluster size is bigger than the size taken by four mft records, the
 912          * mft mirror contains as many mft records as will fit into one
 913          * cluster.
 914          */
 915         if (vol->cluster_size <= (4 << vol->mft_record_size_bits))
 916                 vol->mftmirr_size = 4;
 917         else
 918                 vol->mftmirr_size = vol->cluster_size >>
 919                                 vol->mft_record_size_bits;
 920         ntfs_debug("vol->mftmirr_size = %i", vol->mftmirr_size);
 921 #endif /* NTFS_RW */
 922         vol->serial_no = le64_to_cpu(b->volume_serial_number);
 923         ntfs_debug("vol->serial_no = 0x%llx",
 924                         (unsigned long long)vol->serial_no);
 925         return true;
 926 }
 927 
 928 /**
 929  * ntfs_setup_allocators - initialize the cluster and mft allocators
 930  * @vol:        volume structure for which to setup the allocators
 931  *
 932  * Setup the cluster (lcn) and mft allocators to the starting values.
 933  */
 934 static void ntfs_setup_allocators(ntfs_volume *vol)
 935 {
 936 #ifdef NTFS_RW
 937         LCN mft_zone_size, mft_lcn;
 938 #endif /* NTFS_RW */
 939 
 940         ntfs_debug("vol->mft_zone_multiplier = 0x%x",
 941                         vol->mft_zone_multiplier);
 942 #ifdef NTFS_RW
 943         /* Determine the size of the MFT zone. */
 944         mft_zone_size = vol->nr_clusters;
 945         switch (vol->mft_zone_multiplier) {  /* % of volume size in clusters */
 946         case 4:
 947                 mft_zone_size >>= 1;                    /* 50%   */
 948                 break;
 949         case 3:
 950                 mft_zone_size = (mft_zone_size +
 951                                 (mft_zone_size >> 1)) >> 2;     /* 37.5% */
 952                 break;
 953         case 2:
 954                 mft_zone_size >>= 2;                    /* 25%   */
 955                 break;
 956         /* case 1: */
 957         default:
 958                 mft_zone_size >>= 3;                    /* 12.5% */
 959                 break;
 960         }
 961         /* Setup the mft zone. */
 962         vol->mft_zone_start = vol->mft_zone_pos = vol->mft_lcn;
 963         ntfs_debug("vol->mft_zone_pos = 0x%llx",
 964                         (unsigned long long)vol->mft_zone_pos);
 965         /*
 966          * Calculate the mft_lcn for an unmodified NTFS volume (see mkntfs
 967          * source) and if the actual mft_lcn is in the expected place or even
 968          * further to the front of the volume, extend the mft_zone to cover the
 969          * beginning of the volume as well.  This is in order to protect the
 970          * area reserved for the mft bitmap as well within the mft_zone itself.
 971          * On non-standard volumes we do not protect it as the overhead would
 972          * be higher than the speed increase we would get by doing it.
 973          */
 974         mft_lcn = (8192 + 2 * vol->cluster_size - 1) / vol->cluster_size;
 975         if (mft_lcn * vol->cluster_size < 16 * 1024)
 976                 mft_lcn = (16 * 1024 + vol->cluster_size - 1) /
 977                                 vol->cluster_size;
 978         if (vol->mft_zone_start <= mft_lcn)
 979                 vol->mft_zone_start = 0;
 980         ntfs_debug("vol->mft_zone_start = 0x%llx",
 981                         (unsigned long long)vol->mft_zone_start);
 982         /*
 983          * Need to cap the mft zone on non-standard volumes so that it does
 984          * not point outside the boundaries of the volume.  We do this by
 985          * halving the zone size until we are inside the volume.
 986          */
 987         vol->mft_zone_end = vol->mft_lcn + mft_zone_size;
 988         while (vol->mft_zone_end >= vol->nr_clusters) {
 989                 mft_zone_size >>= 1;
 990                 vol->mft_zone_end = vol->mft_lcn + mft_zone_size;
 991         }
 992         ntfs_debug("vol->mft_zone_end = 0x%llx",
 993                         (unsigned long long)vol->mft_zone_end);
 994         /*
 995          * Set the current position within each data zone to the start of the
 996          * respective zone.
 997          */
 998         vol->data1_zone_pos = vol->mft_zone_end;
 999         ntfs_debug("vol->data1_zone_pos = 0x%llx",
1000                         (unsigned long long)vol->data1_zone_pos);
1001         vol->data2_zone_pos = 0;
1002         ntfs_debug("vol->data2_zone_pos = 0x%llx",
1003                         (unsigned long long)vol->data2_zone_pos);
1004 
1005         /* Set the mft data allocation position to mft record 24. */
1006         vol->mft_data_pos = 24;
1007         ntfs_debug("vol->mft_data_pos = 0x%llx",
1008                         (unsigned long long)vol->mft_data_pos);
1009 #endif /* NTFS_RW */
1010 }
1011 
1012 #ifdef NTFS_RW
1013 
1014 /**
1015  * load_and_init_mft_mirror - load and setup the mft mirror inode for a volume
1016  * @vol:        ntfs super block describing device whose mft mirror to load
1017  *
1018  * Return 'true' on success or 'false' on error.
1019  */
1020 static bool load_and_init_mft_mirror(ntfs_volume *vol)
1021 {
1022         struct inode *tmp_ino;
1023         ntfs_inode *tmp_ni;
1024 
1025         ntfs_debug("Entering.");
1026         /* Get mft mirror inode. */
1027         tmp_ino = ntfs_iget(vol->sb, FILE_MFTMirr);
1028         if (IS_ERR(tmp_ino) || is_bad_inode(tmp_ino)) {
1029                 if (!IS_ERR(tmp_ino))
1030                         iput(tmp_ino);
1031                 /* Caller will display error message. */
1032                 return false;
1033         }
1034         /*
1035          * Re-initialize some specifics about $MFTMirr's inode as
1036          * ntfs_read_inode() will have set up the default ones.
1037          */
1038         /* Set uid and gid to root. */
1039         tmp_ino->i_uid = GLOBAL_ROOT_UID;
1040         tmp_ino->i_gid = GLOBAL_ROOT_GID;
1041         /* Regular file.  No access for anyone. */
1042         tmp_ino->i_mode = S_IFREG;
1043         /* No VFS initiated operations allowed for $MFTMirr. */
1044         tmp_ino->i_op = &ntfs_empty_inode_ops;
1045         tmp_ino->i_fop = &ntfs_empty_file_ops;
1046         /* Put in our special address space operations. */
1047         tmp_ino->i_mapping->a_ops = &ntfs_mst_aops;
1048         tmp_ni = NTFS_I(tmp_ino);
1049         /* The $MFTMirr, like the $MFT is multi sector transfer protected. */
1050         NInoSetMstProtected(tmp_ni);
1051         NInoSetSparseDisabled(tmp_ni);
1052         /*
1053          * Set up our little cheat allowing us to reuse the async read io
1054          * completion handler for directories.
1055          */
1056         tmp_ni->itype.index.block_size = vol->mft_record_size;
1057         tmp_ni->itype.index.block_size_bits = vol->mft_record_size_bits;
1058         vol->mftmirr_ino = tmp_ino;
1059         ntfs_debug("Done.");
1060         return true;
1061 }
1062 
1063 /**
1064  * check_mft_mirror - compare contents of the mft mirror with the mft
1065  * @vol:        ntfs super block describing device whose mft mirror to check
1066  *
1067  * Return 'true' on success or 'false' on error.
1068  *
1069  * Note, this function also results in the mft mirror runlist being completely
1070  * mapped into memory.  The mft mirror write code requires this and will BUG()
1071  * should it find an unmapped runlist element.
1072  */
1073 static bool check_mft_mirror(ntfs_volume *vol)
1074 {
1075         struct super_block *sb = vol->sb;
1076         ntfs_inode *mirr_ni;
1077         struct page *mft_page, *mirr_page;
1078         u8 *kmft, *kmirr;
1079         runlist_element *rl, rl2[2];
1080         pgoff_t index;
1081         int mrecs_per_page, i;
1082 
1083         ntfs_debug("Entering.");
1084         /* Compare contents of $MFT and $MFTMirr. */
1085         mrecs_per_page = PAGE_SIZE / vol->mft_record_size;
1086         BUG_ON(!mrecs_per_page);
1087         BUG_ON(!vol->mftmirr_size);
1088         mft_page = mirr_page = NULL;
1089         kmft = kmirr = NULL;
1090         index = i = 0;
1091         do {
1092                 u32 bytes;
1093 
1094                 /* Switch pages if necessary. */
1095                 if (!(i % mrecs_per_page)) {
1096                         if (index) {
1097                                 ntfs_unmap_page(mft_page);
1098                                 ntfs_unmap_page(mirr_page);
1099                         }
1100                         /* Get the $MFT page. */
1101                         mft_page = ntfs_map_page(vol->mft_ino->i_mapping,
1102                                         index);
1103                         if (IS_ERR(mft_page)) {
1104                                 ntfs_error(sb, "Failed to read $MFT.");
1105                                 return false;
1106                         }
1107                         kmft = page_address(mft_page);
1108                         /* Get the $MFTMirr page. */
1109                         mirr_page = ntfs_map_page(vol->mftmirr_ino->i_mapping,
1110                                         index);
1111                         if (IS_ERR(mirr_page)) {
1112                                 ntfs_error(sb, "Failed to read $MFTMirr.");
1113                                 goto mft_unmap_out;
1114                         }
1115                         kmirr = page_address(mirr_page);
1116                         ++index;
1117                 }
1118                 /* Do not check the record if it is not in use. */
1119                 if (((MFT_RECORD*)kmft)->flags & MFT_RECORD_IN_USE) {
1120                         /* Make sure the record is ok. */
1121                         if (ntfs_is_baad_recordp((le32*)kmft)) {
1122                                 ntfs_error(sb, "Incomplete multi sector "
1123                                                 "transfer detected in mft "
1124                                                 "record %i.", i);
1125 mm_unmap_out:
1126                                 ntfs_unmap_page(mirr_page);
1127 mft_unmap_out:
1128                                 ntfs_unmap_page(mft_page);
1129                                 return false;
1130                         }
1131                 }
1132                 /* Do not check the mirror record if it is not in use. */
1133                 if (((MFT_RECORD*)kmirr)->flags & MFT_RECORD_IN_USE) {
1134                         if (ntfs_is_baad_recordp((le32*)kmirr)) {
1135                                 ntfs_error(sb, "Incomplete multi sector "
1136                                                 "transfer detected in mft "
1137                                                 "mirror record %i.", i);
1138                                 goto mm_unmap_out;
1139                         }
1140                 }
1141                 /* Get the amount of data in the current record. */
1142                 bytes = le32_to_cpu(((MFT_RECORD*)kmft)->bytes_in_use);
1143                 if (bytes < sizeof(MFT_RECORD_OLD) ||
1144                                 bytes > vol->mft_record_size ||
1145                                 ntfs_is_baad_recordp((le32*)kmft)) {
1146                         bytes = le32_to_cpu(((MFT_RECORD*)kmirr)->bytes_in_use);
1147                         if (bytes < sizeof(MFT_RECORD_OLD) ||
1148                                         bytes > vol->mft_record_size ||
1149                                         ntfs_is_baad_recordp((le32*)kmirr))
1150                                 bytes = vol->mft_record_size;
1151                 }
1152                 /* Compare the two records. */
1153                 if (memcmp(kmft, kmirr, bytes)) {
1154                         ntfs_error(sb, "$MFT and $MFTMirr (record %i) do not "
1155                                         "match.  Run ntfsfix or chkdsk.", i);
1156                         goto mm_unmap_out;
1157                 }
1158                 kmft += vol->mft_record_size;
1159                 kmirr += vol->mft_record_size;
1160         } while (++i < vol->mftmirr_size);
1161         /* Release the last pages. */
1162         ntfs_unmap_page(mft_page);
1163         ntfs_unmap_page(mirr_page);
1164 
1165         /* Construct the mft mirror runlist by hand. */
1166         rl2[0].vcn = 0;
1167         rl2[0].lcn = vol->mftmirr_lcn;
1168         rl2[0].length = (vol->mftmirr_size * vol->mft_record_size +
1169                         vol->cluster_size - 1) / vol->cluster_size;
1170         rl2[1].vcn = rl2[0].length;
1171         rl2[1].lcn = LCN_ENOENT;
1172         rl2[1].length = 0;
1173         /*
1174          * Because we have just read all of the mft mirror, we know we have
1175          * mapped the full runlist for it.
1176          */
1177         mirr_ni = NTFS_I(vol->mftmirr_ino);
1178         down_read(&mirr_ni->runlist.lock);
1179         rl = mirr_ni->runlist.rl;
1180         /* Compare the two runlists.  They must be identical. */
1181         i = 0;
1182         do {
1183                 if (rl2[i].vcn != rl[i].vcn || rl2[i].lcn != rl[i].lcn ||
1184                                 rl2[i].length != rl[i].length) {
1185                         ntfs_error(sb, "$MFTMirr location mismatch.  "
1186                                         "Run chkdsk.");
1187                         up_read(&mirr_ni->runlist.lock);
1188                         return false;
1189                 }
1190         } while (rl2[i++].length);
1191         up_read(&mirr_ni->runlist.lock);
1192         ntfs_debug("Done.");
1193         return true;
1194 }
1195 
1196 /**
1197  * load_and_check_logfile - load and check the logfile inode for a volume
1198  * @vol:        ntfs super block describing device whose logfile to load
1199  *
1200  * Return 'true' on success or 'false' on error.
1201  */
1202 static bool load_and_check_logfile(ntfs_volume *vol,
1203                 RESTART_PAGE_HEADER **rp)
1204 {
1205         struct inode *tmp_ino;
1206 
1207         ntfs_debug("Entering.");
1208         tmp_ino = ntfs_iget(vol->sb, FILE_LogFile);
1209         if (IS_ERR(tmp_ino) || is_bad_inode(tmp_ino)) {
1210                 if (!IS_ERR(tmp_ino))
1211                         iput(tmp_ino);
1212                 /* Caller will display error message. */
1213                 return false;
1214         }
1215         if (!ntfs_check_logfile(tmp_ino, rp)) {
1216                 iput(tmp_ino);
1217                 /* ntfs_check_logfile() will have displayed error output. */
1218                 return false;
1219         }
1220         NInoSetSparseDisabled(NTFS_I(tmp_ino));
1221         vol->logfile_ino = tmp_ino;
1222         ntfs_debug("Done.");
1223         return true;
1224 }
1225 
1226 #define NTFS_HIBERFIL_HEADER_SIZE       4096
1227 
1228 /**
1229  * check_windows_hibernation_status - check if Windows is suspended on a volume
1230  * @vol:        ntfs super block of device to check
1231  *
1232  * Check if Windows is hibernated on the ntfs volume @vol.  This is done by
1233  * looking for the file hiberfil.sys in the root directory of the volume.  If
1234  * the file is not present Windows is definitely not suspended.
1235  *
1236  * If hiberfil.sys exists and is less than 4kiB in size it means Windows is
1237  * definitely suspended (this volume is not the system volume).  Caveat:  on a
1238  * system with many volumes it is possible that the < 4kiB check is bogus but
1239  * for now this should do fine.
1240  *
1241  * If hiberfil.sys exists and is larger than 4kiB in size, we need to read the
1242  * hiberfil header (which is the first 4kiB).  If this begins with "hibr",
1243  * Windows is definitely suspended.  If it is completely full of zeroes,
1244  * Windows is definitely not hibernated.  Any other case is treated as if
1245  * Windows is suspended.  This caters for the above mentioned caveat of a
1246  * system with many volumes where no "hibr" magic would be present and there is
1247  * no zero header.
1248  *
1249  * Return 0 if Windows is not hibernated on the volume, >0 if Windows is
1250  * hibernated on the volume, and -errno on error.
1251  */
1252 static int check_windows_hibernation_status(ntfs_volume *vol)
1253 {
1254         MFT_REF mref;
1255         struct inode *vi;
1256         struct page *page;
1257         u32 *kaddr, *kend;
1258         ntfs_name *name = NULL;
1259         int ret = 1;
1260         static const ntfschar hiberfil[13] = { cpu_to_le16('h'),
1261                         cpu_to_le16('i'), cpu_to_le16('b'),
1262                         cpu_to_le16('e'), cpu_to_le16('r'),
1263                         cpu_to_le16('f'), cpu_to_le16('i'),
1264                         cpu_to_le16('l'), cpu_to_le16('.'),
1265                         cpu_to_le16('s'), cpu_to_le16('y'),
1266                         cpu_to_le16('s'), 0 };
1267 
1268         ntfs_debug("Entering.");
1269         /*
1270          * Find the inode number for the hibernation file by looking up the
1271          * filename hiberfil.sys in the root directory.
1272          */
1273         inode_lock(vol->root_ino);
1274         mref = ntfs_lookup_inode_by_name(NTFS_I(vol->root_ino), hiberfil, 12,
1275                         &name);
1276         inode_unlock(vol->root_ino);
1277         if (IS_ERR_MREF(mref)) {
1278                 ret = MREF_ERR(mref);
1279                 /* If the file does not exist, Windows is not hibernated. */
1280                 if (ret == -ENOENT) {
1281                         ntfs_debug("hiberfil.sys not present.  Windows is not "
1282                                         "hibernated on the volume.");
1283                         return 0;
1284                 }
1285                 /* A real error occurred. */
1286                 ntfs_error(vol->sb, "Failed to find inode number for "
1287                                 "hiberfil.sys.");
1288                 return ret;
1289         }
1290         /* We do not care for the type of match that was found. */
1291         kfree(name);
1292         /* Get the inode. */
1293         vi = ntfs_iget(vol->sb, MREF(mref));
1294         if (IS_ERR(vi) || is_bad_inode(vi)) {
1295                 if (!IS_ERR(vi))
1296                         iput(vi);
1297                 ntfs_error(vol->sb, "Failed to load hiberfil.sys.");
1298                 return IS_ERR(vi) ? PTR_ERR(vi) : -EIO;
1299         }
1300         if (unlikely(i_size_read(vi) < NTFS_HIBERFIL_HEADER_SIZE)) {
1301                 ntfs_debug("hiberfil.sys is smaller than 4kiB (0x%llx).  "
1302                                 "Windows is hibernated on the volume.  This "
1303                                 "is not the system volume.", i_size_read(vi));
1304                 goto iput_out;
1305         }
1306         page = ntfs_map_page(vi->i_mapping, 0);
1307         if (IS_ERR(page)) {
1308                 ntfs_error(vol->sb, "Failed to read from hiberfil.sys.");
1309                 ret = PTR_ERR(page);
1310                 goto iput_out;
1311         }
1312         kaddr = (u32*)page_address(page);
1313         if (*(le32*)kaddr == cpu_to_le32(0x72626968)/*'hibr'*/) {
1314                 ntfs_debug("Magic \"hibr\" found in hiberfil.sys.  Windows is "
1315                                 "hibernated on the volume.  This is the "
1316                                 "system volume.");
1317                 goto unm_iput_out;
1318         }
1319         kend = kaddr + NTFS_HIBERFIL_HEADER_SIZE/sizeof(*kaddr);
1320         do {
1321                 if (unlikely(*kaddr)) {
1322                         ntfs_debug("hiberfil.sys is larger than 4kiB "
1323                                         "(0x%llx), does not contain the "
1324                                         "\"hibr\" magic, and does not have a "
1325                                         "zero header.  Windows is hibernated "
1326                                         "on the volume.  This is not the "
1327                                         "system volume.", i_size_read(vi));
1328                         goto unm_iput_out;
1329                 }
1330         } while (++kaddr < kend);
1331         ntfs_debug("hiberfil.sys contains a zero header.  Windows is not "
1332                         "hibernated on the volume.  This is the system "
1333                         "volume.");
1334         ret = 0;
1335 unm_iput_out:
1336         ntfs_unmap_page(page);
1337 iput_out:
1338         iput(vi);
1339         return ret;
1340 }
1341 
1342 /**
1343  * load_and_init_quota - load and setup the quota file for a volume if present
1344  * @vol:        ntfs super block describing device whose quota file to load
1345  *
1346  * Return 'true' on success or 'false' on error.  If $Quota is not present, we
1347  * leave vol->quota_ino as NULL and return success.
1348  */
1349 static bool load_and_init_quota(ntfs_volume *vol)
1350 {
1351         MFT_REF mref;
1352         struct inode *tmp_ino;
1353         ntfs_name *name = NULL;
1354         static const ntfschar Quota[7] = { cpu_to_le16('$'),
1355                         cpu_to_le16('Q'), cpu_to_le16('u'),
1356                         cpu_to_le16('o'), cpu_to_le16('t'),
1357                         cpu_to_le16('a'), 0 };
1358         static ntfschar Q[3] = { cpu_to_le16('$'),
1359                         cpu_to_le16('Q'), 0 };
1360 
1361         ntfs_debug("Entering.");
1362         /*
1363          * Find the inode number for the quota file by looking up the filename
1364          * $Quota in the extended system files directory $Extend.
1365          */
1366         inode_lock(vol->extend_ino);
1367         mref = ntfs_lookup_inode_by_name(NTFS_I(vol->extend_ino), Quota, 6,
1368                         &name);
1369         inode_unlock(vol->extend_ino);
1370         if (IS_ERR_MREF(mref)) {
1371                 /*
1372                  * If the file does not exist, quotas are disabled and have
1373                  * never been enabled on this volume, just return success.
1374                  */
1375                 if (MREF_ERR(mref) == -ENOENT) {
1376                         ntfs_debug("$Quota not present.  Volume does not have "
1377                                         "quotas enabled.");
1378                         /*
1379                          * No need to try to set quotas out of date if they are
1380                          * not enabled.
1381                          */
1382                         NVolSetQuotaOutOfDate(vol);
1383                         return true;
1384                 }
1385                 /* A real error occurred. */
1386                 ntfs_error(vol->sb, "Failed to find inode number for $Quota.");
1387                 return false;
1388         }
1389         /* We do not care for the type of match that was found. */
1390         kfree(name);
1391         /* Get the inode. */
1392         tmp_ino = ntfs_iget(vol->sb, MREF(mref));
1393         if (IS_ERR(tmp_ino) || is_bad_inode(tmp_ino)) {
1394                 if (!IS_ERR(tmp_ino))
1395                         iput(tmp_ino);
1396                 ntfs_error(vol->sb, "Failed to load $Quota.");
1397                 return false;
1398         }
1399         vol->quota_ino = tmp_ino;
1400         /* Get the $Q index allocation attribute. */
1401         tmp_ino = ntfs_index_iget(vol->quota_ino, Q, 2);
1402         if (IS_ERR(tmp_ino)) {
1403                 ntfs_error(vol->sb, "Failed to load $Quota/$Q index.");
1404                 return false;
1405         }
1406         vol->quota_q_ino = tmp_ino;
1407         ntfs_debug("Done.");
1408         return true;
1409 }
1410 
1411 /**
1412  * load_and_init_usnjrnl - load and setup the transaction log if present
1413  * @vol:        ntfs super block describing device whose usnjrnl file to load
1414  *
1415  * Return 'true' on success or 'false' on error.
1416  *
1417  * If $UsnJrnl is not present or in the process of being disabled, we set
1418  * NVolUsnJrnlStamped() and return success.
1419  *
1420  * If the $UsnJrnl $DATA/$J attribute has a size equal to the lowest valid usn,
1421  * i.e. transaction logging has only just been enabled or the journal has been
1422  * stamped and nothing has been logged since, we also set NVolUsnJrnlStamped()
1423  * and return success.
1424  */
1425 static bool load_and_init_usnjrnl(ntfs_volume *vol)
1426 {
1427         MFT_REF mref;
1428         struct inode *tmp_ino;
1429         ntfs_inode *tmp_ni;
1430         struct page *page;
1431         ntfs_name *name = NULL;
1432         USN_HEADER *uh;
1433         static const ntfschar UsnJrnl[9] = { cpu_to_le16('$'),
1434                         cpu_to_le16('U'), cpu_to_le16('s'),
1435                         cpu_to_le16('n'), cpu_to_le16('J'),
1436                         cpu_to_le16('r'), cpu_to_le16('n'),
1437                         cpu_to_le16('l'), 0 };
1438         static ntfschar Max[5] = { cpu_to_le16('$'),
1439                         cpu_to_le16('M'), cpu_to_le16('a'),
1440                         cpu_to_le16('x'), 0 };
1441         static ntfschar J[3] = { cpu_to_le16('$'),
1442                         cpu_to_le16('J'), 0 };
1443 
1444         ntfs_debug("Entering.");
1445         /*
1446          * Find the inode number for the transaction log file by looking up the
1447          * filename $UsnJrnl in the extended system files directory $Extend.
1448          */
1449         inode_lock(vol->extend_ino);
1450         mref = ntfs_lookup_inode_by_name(NTFS_I(vol->extend_ino), UsnJrnl, 8,
1451                         &name);
1452         inode_unlock(vol->extend_ino);
1453         if (IS_ERR_MREF(mref)) {
1454                 /*
1455                  * If the file does not exist, transaction logging is disabled,
1456                  * just return success.
1457                  */
1458                 if (MREF_ERR(mref) == -ENOENT) {
1459                         ntfs_debug("$UsnJrnl not present.  Volume does not "
1460                                         "have transaction logging enabled.");
1461 not_enabled:
1462                         /*
1463                          * No need to try to stamp the transaction log if
1464                          * transaction logging is not enabled.
1465                          */
1466                         NVolSetUsnJrnlStamped(vol);
1467                         return true;
1468                 }
1469                 /* A real error occurred. */
1470                 ntfs_error(vol->sb, "Failed to find inode number for "
1471                                 "$UsnJrnl.");
1472                 return false;
1473         }
1474         /* We do not care for the type of match that was found. */
1475         kfree(name);
1476         /* Get the inode. */
1477         tmp_ino = ntfs_iget(vol->sb, MREF(mref));
1478         if (IS_ERR(tmp_ino) || unlikely(is_bad_inode(tmp_ino))) {
1479                 if (!IS_ERR(tmp_ino))
1480                         iput(tmp_ino);
1481                 ntfs_error(vol->sb, "Failed to load $UsnJrnl.");
1482                 return false;
1483         }
1484         vol->usnjrnl_ino = tmp_ino;
1485         /*
1486          * If the transaction log is in the process of being deleted, we can
1487          * ignore it.
1488          */
1489         if (unlikely(vol->vol_flags & VOLUME_DELETE_USN_UNDERWAY)) {
1490                 ntfs_debug("$UsnJrnl in the process of being disabled.  "
1491                                 "Volume does not have transaction logging "
1492                                 "enabled.");
1493                 goto not_enabled;
1494         }
1495         /* Get the $DATA/$Max attribute. */
1496         tmp_ino = ntfs_attr_iget(vol->usnjrnl_ino, AT_DATA, Max, 4);
1497         if (IS_ERR(tmp_ino)) {
1498                 ntfs_error(vol->sb, "Failed to load $UsnJrnl/$DATA/$Max "
1499                                 "attribute.");
1500                 return false;
1501         }
1502         vol->usnjrnl_max_ino = tmp_ino;
1503         if (unlikely(i_size_read(tmp_ino) < sizeof(USN_HEADER))) {
1504                 ntfs_error(vol->sb, "Found corrupt $UsnJrnl/$DATA/$Max "
1505                                 "attribute (size is 0x%llx but should be at "
1506                                 "least 0x%zx bytes).", i_size_read(tmp_ino),
1507                                 sizeof(USN_HEADER));
1508                 return false;
1509         }
1510         /* Get the $DATA/$J attribute. */
1511         tmp_ino = ntfs_attr_iget(vol->usnjrnl_ino, AT_DATA, J, 2);
1512         if (IS_ERR(tmp_ino)) {
1513                 ntfs_error(vol->sb, "Failed to load $UsnJrnl/$DATA/$J "
1514                                 "attribute.");
1515                 return false;
1516         }
1517         vol->usnjrnl_j_ino = tmp_ino;
1518         /* Verify $J is non-resident and sparse. */
1519         tmp_ni = NTFS_I(vol->usnjrnl_j_ino);
1520         if (unlikely(!NInoNonResident(tmp_ni) || !NInoSparse(tmp_ni))) {
1521                 ntfs_error(vol->sb, "$UsnJrnl/$DATA/$J attribute is resident "
1522                                 "and/or not sparse.");
1523                 return false;
1524         }
1525         /* Read the USN_HEADER from $DATA/$Max. */
1526         page = ntfs_map_page(vol->usnjrnl_max_ino->i_mapping, 0);
1527         if (IS_ERR(page)) {
1528                 ntfs_error(vol->sb, "Failed to read from $UsnJrnl/$DATA/$Max "
1529                                 "attribute.");
1530                 return false;
1531         }
1532         uh = (USN_HEADER*)page_address(page);
1533         /* Sanity check the $Max. */
1534         if (unlikely(sle64_to_cpu(uh->allocation_delta) >
1535                         sle64_to_cpu(uh->maximum_size))) {
1536                 ntfs_error(vol->sb, "Allocation delta (0x%llx) exceeds "
1537                                 "maximum size (0x%llx).  $UsnJrnl is corrupt.",
1538                                 (long long)sle64_to_cpu(uh->allocation_delta),
1539                                 (long long)sle64_to_cpu(uh->maximum_size));
1540                 ntfs_unmap_page(page);
1541                 return false;
1542         }
1543         /*
1544          * If the transaction log has been stamped and nothing has been written
1545          * to it since, we do not need to stamp it.
1546          */
1547         if (unlikely(sle64_to_cpu(uh->lowest_valid_usn) >=
1548                         i_size_read(vol->usnjrnl_j_ino))) {
1549                 if (likely(sle64_to_cpu(uh->lowest_valid_usn) ==
1550                                 i_size_read(vol->usnjrnl_j_ino))) {
1551                         ntfs_unmap_page(page);
1552                         ntfs_debug("$UsnJrnl is enabled but nothing has been "
1553                                         "logged since it was last stamped.  "
1554                                         "Treating this as if the volume does "
1555                                         "not have transaction logging "
1556                                         "enabled.");
1557                         goto not_enabled;
1558                 }
1559                 ntfs_error(vol->sb, "$UsnJrnl has lowest valid usn (0x%llx) "
1560                                 "which is out of bounds (0x%llx).  $UsnJrnl "
1561                                 "is corrupt.",
1562                                 (long long)sle64_to_cpu(uh->lowest_valid_usn),
1563                                 i_size_read(vol->usnjrnl_j_ino));
1564                 ntfs_unmap_page(page);
1565                 return false;
1566         }
1567         ntfs_unmap_page(page);
1568         ntfs_debug("Done.");
1569         return true;
1570 }
1571 
1572 /**
1573  * load_and_init_attrdef - load the attribute definitions table for a volume
1574  * @vol:        ntfs super block describing device whose attrdef to load
1575  *
1576  * Return 'true' on success or 'false' on error.
1577  */
1578 static bool load_and_init_attrdef(ntfs_volume *vol)
1579 {
1580         loff_t i_size;
1581         struct super_block *sb = vol->sb;
1582         struct inode *ino;
1583         struct page *page;
1584         pgoff_t index, max_index;
1585         unsigned int size;
1586 
1587         ntfs_debug("Entering.");
1588         /* Read attrdef table and setup vol->attrdef and vol->attrdef_size. */
1589         ino = ntfs_iget(sb, FILE_AttrDef);
1590         if (IS_ERR(ino) || is_bad_inode(ino)) {
1591                 if (!IS_ERR(ino))
1592                         iput(ino);
1593                 goto failed;
1594         }
1595         NInoSetSparseDisabled(NTFS_I(ino));
1596         /* The size of FILE_AttrDef must be above 0 and fit inside 31 bits. */
1597         i_size = i_size_read(ino);
1598         if (i_size <= 0 || i_size > 0x7fffffff)
1599                 goto iput_failed;
1600         vol->attrdef = (ATTR_DEF*)ntfs_malloc_nofs(i_size);
1601         if (!vol->attrdef)
1602                 goto iput_failed;
1603         index = 0;
1604         max_index = i_size >> PAGE_SHIFT;
1605         size = PAGE_SIZE;
1606         while (index < max_index) {
1607                 /* Read the attrdef table and copy it into the linear buffer. */
1608 read_partial_attrdef_page:
1609                 page = ntfs_map_page(ino->i_mapping, index);
1610                 if (IS_ERR(page))
1611                         goto free_iput_failed;
1612                 memcpy((u8*)vol->attrdef + (index++ << PAGE_SHIFT),
1613                                 page_address(page), size);
1614                 ntfs_unmap_page(page);
1615         };
1616         if (size == PAGE_SIZE) {
1617                 size = i_size & ~PAGE_MASK;
1618                 if (size)
1619                         goto read_partial_attrdef_page;
1620         }
1621         vol->attrdef_size = i_size;
1622         ntfs_debug("Read %llu bytes from $AttrDef.", i_size);
1623         iput(ino);
1624         return true;
1625 free_iput_failed:
1626         ntfs_free(vol->attrdef);
1627         vol->attrdef = NULL;
1628 iput_failed:
1629         iput(ino);
1630 failed:
1631         ntfs_error(sb, "Failed to initialize attribute definition table.");
1632         return false;
1633 }
1634 
1635 #endif /* NTFS_RW */
1636 
1637 /**
1638  * load_and_init_upcase - load the upcase table for an ntfs volume
1639  * @vol:        ntfs super block describing device whose upcase to load
1640  *
1641  * Return 'true' on success or 'false' on error.
1642  */
1643 static bool load_and_init_upcase(ntfs_volume *vol)
1644 {
1645         loff_t i_size;
1646         struct super_block *sb = vol->sb;
1647         struct inode *ino;
1648         struct page *page;
1649         pgoff_t index, max_index;
1650         unsigned int size;
1651         int i, max;
1652 
1653         ntfs_debug("Entering.");
1654         /* Read upcase table and setup vol->upcase and vol->upcase_len. */
1655         ino = ntfs_iget(sb, FILE_UpCase);
1656         if (IS_ERR(ino) || is_bad_inode(ino)) {
1657                 if (!IS_ERR(ino))
1658                         iput(ino);
1659                 goto upcase_failed;
1660         }
1661         /*
1662          * The upcase size must not be above 64k Unicode characters, must not
1663          * be zero and must be a multiple of sizeof(ntfschar).
1664          */
1665         i_size = i_size_read(ino);
1666         if (!i_size || i_size & (sizeof(ntfschar) - 1) ||
1667                         i_size > 64ULL * 1024 * sizeof(ntfschar))
1668                 goto iput_upcase_failed;
1669         vol->upcase = (ntfschar*)ntfs_malloc_nofs(i_size);
1670         if (!vol->upcase)
1671                 goto iput_upcase_failed;
1672         index = 0;
1673         max_index = i_size >> PAGE_SHIFT;
1674         size = PAGE_SIZE;
1675         while (index < max_index) {
1676                 /* Read the upcase table and copy it into the linear buffer. */
1677 read_partial_upcase_page:
1678                 page = ntfs_map_page(ino->i_mapping, index);
1679                 if (IS_ERR(page))
1680                         goto iput_upcase_failed;
1681                 memcpy((char*)vol->upcase + (index++ << PAGE_SHIFT),
1682                                 page_address(page), size);
1683                 ntfs_unmap_page(page);
1684         };
1685         if (size == PAGE_SIZE) {
1686                 size = i_size & ~PAGE_MASK;
1687                 if (size)
1688                         goto read_partial_upcase_page;
1689         }
1690         vol->upcase_len = i_size >> UCHAR_T_SIZE_BITS;
1691         ntfs_debug("Read %llu bytes from $UpCase (expected %zu bytes).",
1692                         i_size, 64 * 1024 * sizeof(ntfschar));
1693         iput(ino);
1694         mutex_lock(&ntfs_lock);
1695         if (!default_upcase) {
1696                 ntfs_debug("Using volume specified $UpCase since default is "
1697                                 "not present.");
1698                 mutex_unlock(&ntfs_lock);
1699                 return true;
1700         }
1701         max = default_upcase_len;
1702         if (max > vol->upcase_len)
1703                 max = vol->upcase_len;
1704         for (i = 0; i < max; i++)
1705                 if (vol->upcase[i] != default_upcase[i])
1706                         break;
1707         if (i == max) {
1708                 ntfs_free(vol->upcase);
1709                 vol->upcase = default_upcase;
1710                 vol->upcase_len = max;
1711                 ntfs_nr_upcase_users++;
1712                 mutex_unlock(&ntfs_lock);
1713                 ntfs_debug("Volume specified $UpCase matches default. Using "
1714                                 "default.");
1715                 return true;
1716         }
1717         mutex_unlock(&ntfs_lock);
1718         ntfs_debug("Using volume specified $UpCase since it does not match "
1719                         "the default.");
1720         return true;
1721 iput_upcase_failed:
1722         iput(ino);
1723         ntfs_free(vol->upcase);
1724         vol->upcase = NULL;
1725 upcase_failed:
1726         mutex_lock(&ntfs_lock);
1727         if (default_upcase) {
1728                 vol->upcase = default_upcase;
1729                 vol->upcase_len = default_upcase_len;
1730                 ntfs_nr_upcase_users++;
1731                 mutex_unlock(&ntfs_lock);
1732                 ntfs_error(sb, "Failed to load $UpCase from the volume. Using "
1733                                 "default.");
1734                 return true;
1735         }
1736         mutex_unlock(&ntfs_lock);
1737         ntfs_error(sb, "Failed to initialize upcase table.");
1738         return false;
1739 }
1740 
1741 /*
1742  * The lcn and mft bitmap inodes are NTFS-internal inodes with
1743  * their own special locking rules:
1744  */
1745 static struct lock_class_key
1746         lcnbmp_runlist_lock_key, lcnbmp_mrec_lock_key,
1747         mftbmp_runlist_lock_key, mftbmp_mrec_lock_key;
1748 
1749 /**
1750  * load_system_files - open the system files using normal functions
1751  * @vol:        ntfs super block describing device whose system files to load
1752  *
1753  * Open the system files with normal access functions and complete setting up
1754  * the ntfs super block @vol.
1755  *
1756  * Return 'true' on success or 'false' on error.
1757  */
1758 static bool load_system_files(ntfs_volume *vol)
1759 {
1760         struct super_block *sb = vol->sb;
1761         MFT_RECORD *m;
1762         VOLUME_INFORMATION *vi;
1763         ntfs_attr_search_ctx *ctx;
1764 #ifdef NTFS_RW
1765         RESTART_PAGE_HEADER *rp;
1766         int err;
1767 #endif /* NTFS_RW */
1768 
1769         ntfs_debug("Entering.");
1770 #ifdef NTFS_RW
1771         /* Get mft mirror inode compare the contents of $MFT and $MFTMirr. */
1772         if (!load_and_init_mft_mirror(vol) || !check_mft_mirror(vol)) {
1773                 static const char *es1 = "Failed to load $MFTMirr";
1774                 static const char *es2 = "$MFTMirr does not match $MFT";
1775                 static const char *es3 = ".  Run ntfsfix and/or chkdsk.";
1776 
1777                 /* If a read-write mount, convert it to a read-only mount. */
1778                 if (!sb_rdonly(sb)) {
1779                         if (!(vol->on_errors & (ON_ERRORS_REMOUNT_RO |
1780                                         ON_ERRORS_CONTINUE))) {
1781                                 ntfs_error(sb, "%s and neither on_errors="
1782                                                 "continue nor on_errors="
1783                                                 "remount-ro was specified%s",
1784                                                 !vol->mftmirr_ino ? es1 : es2,
1785                                                 es3);
1786                                 goto iput_mirr_err_out;
1787                         }
1788                         sb->s_flags |= SB_RDONLY;
1789                         ntfs_error(sb, "%s.  Mounting read-only%s",
1790                                         !vol->mftmirr_ino ? es1 : es2, es3);
1791                 } else
1792                         ntfs_warning(sb, "%s.  Will not be able to remount "
1793                                         "read-write%s",
1794                                         !vol->mftmirr_ino ? es1 : es2, es3);
1795                 /* This will prevent a read-write remount. */
1796                 NVolSetErrors(vol);
1797         }
1798 #endif /* NTFS_RW */
1799         /* Get mft bitmap attribute inode. */
1800         vol->mftbmp_ino = ntfs_attr_iget(vol->mft_ino, AT_BITMAP, NULL, 0);
1801         if (IS_ERR(vol->mftbmp_ino)) {
1802                 ntfs_error(sb, "Failed to load $MFT/$BITMAP attribute.");
1803                 goto iput_mirr_err_out;
1804         }
1805         lockdep_set_class(&NTFS_I(vol->mftbmp_ino)->runlist.lock,
1806                            &mftbmp_runlist_lock_key);
1807         lockdep_set_class(&NTFS_I(vol->mftbmp_ino)->mrec_lock,
1808                            &mftbmp_mrec_lock_key);
1809         /* Read upcase table and setup @vol->upcase and @vol->upcase_len. */
1810         if (!load_and_init_upcase(vol))
1811                 goto iput_mftbmp_err_out;
1812 #ifdef NTFS_RW
1813         /*
1814          * Read attribute definitions table and setup @vol->attrdef and
1815          * @vol->attrdef_size.
1816          */
1817         if (!load_and_init_attrdef(vol))
1818                 goto iput_upcase_err_out;
1819 #endif /* NTFS_RW */
1820         /*
1821          * Get the cluster allocation bitmap inode and verify the size, no
1822          * need for any locking at this stage as we are already running
1823          * exclusively as we are mount in progress task.
1824          */
1825         vol->lcnbmp_ino = ntfs_iget(sb, FILE_Bitmap);
1826         if (IS_ERR(vol->lcnbmp_ino) || is_bad_inode(vol->lcnbmp_ino)) {
1827                 if (!IS_ERR(vol->lcnbmp_ino))
1828                         iput(vol->lcnbmp_ino);
1829                 goto bitmap_failed;
1830         }
1831         lockdep_set_class(&NTFS_I(vol->lcnbmp_ino)->runlist.lock,
1832                            &lcnbmp_runlist_lock_key);
1833         lockdep_set_class(&NTFS_I(vol->lcnbmp_ino)->mrec_lock,
1834                            &lcnbmp_mrec_lock_key);
1835 
1836         NInoSetSparseDisabled(NTFS_I(vol->lcnbmp_ino));
1837         if ((vol->nr_clusters + 7) >> 3 > i_size_read(vol->lcnbmp_ino)) {
1838                 iput(vol->lcnbmp_ino);
1839 bitmap_failed:
1840                 ntfs_error(sb, "Failed to load $Bitmap.");
1841                 goto iput_attrdef_err_out;
1842         }
1843         /*
1844          * Get the volume inode and setup our cache of the volume flags and
1845          * version.
1846          */
1847         vol->vol_ino = ntfs_iget(sb, FILE_Volume);
1848         if (IS_ERR(vol->vol_ino) || is_bad_inode(vol->vol_ino)) {
1849                 if (!IS_ERR(vol->vol_ino))
1850                         iput(vol->vol_ino);
1851 volume_failed:
1852                 ntfs_error(sb, "Failed to load $Volume.");
1853                 goto iput_lcnbmp_err_out;
1854         }
1855         m = map_mft_record(NTFS_I(vol->vol_ino));
1856         if (IS_ERR(m)) {
1857 iput_volume_failed:
1858                 iput(vol->vol_ino);
1859                 goto volume_failed;
1860         }
1861         if (!(ctx = ntfs_attr_get_search_ctx(NTFS_I(vol->vol_ino), m))) {
1862                 ntfs_error(sb, "Failed to get attribute search context.");
1863                 goto get_ctx_vol_failed;
1864         }
1865         if (ntfs_attr_lookup(AT_VOLUME_INFORMATION, NULL, 0, 0, 0, NULL, 0,
1866                         ctx) || ctx->attr->non_resident || ctx->attr->flags) {
1867 err_put_vol:
1868                 ntfs_attr_put_search_ctx(ctx);
1869 get_ctx_vol_failed:
1870                 unmap_mft_record(NTFS_I(vol->vol_ino));
1871                 goto iput_volume_failed;
1872         }
1873         vi = (VOLUME_INFORMATION*)((char*)ctx->attr +
1874                         le16_to_cpu(ctx->attr->data.resident.value_offset));
1875         /* Some bounds checks. */
1876         if ((u8*)vi < (u8*)ctx->attr || (u8*)vi +
1877                         le32_to_cpu(ctx->attr->data.resident.value_length) >
1878                         (u8*)ctx->attr + le32_to_cpu(ctx->attr->length))
1879                 goto err_put_vol;
1880         /* Copy the volume flags and version to the ntfs_volume structure. */
1881         vol->vol_flags = vi->flags;
1882         vol->major_ver = vi->major_ver;
1883         vol->minor_ver = vi->minor_ver;
1884         ntfs_attr_put_search_ctx(ctx);
1885         unmap_mft_record(NTFS_I(vol->vol_ino));
1886         pr_info("volume version %i.%i.\n", vol->major_ver,
1887                         vol->minor_ver);
1888         if (vol->major_ver < 3 && NVolSparseEnabled(vol)) {
1889                 ntfs_warning(vol->sb, "Disabling sparse support due to NTFS "
1890                                 "volume version %i.%i (need at least version "
1891                                 "3.0).", vol->major_ver, vol->minor_ver);
1892                 NVolClearSparseEnabled(vol);
1893         }
1894 #ifdef NTFS_RW
1895         /* Make sure that no unsupported volume flags are set. */
1896         if (vol->vol_flags & VOLUME_MUST_MOUNT_RO_MASK) {
1897                 static const char *es1a = "Volume is dirty";
1898                 static const char *es1b = "Volume has been modified by chkdsk";
1899                 static const char *es1c = "Volume has unsupported flags set";
1900                 static const char *es2a = ".  Run chkdsk and mount in Windows.";
1901                 static const char *es2b = ".  Mount in Windows.";
1902                 const char *es1, *es2;
1903 
1904                 es2 = es2a;
1905                 if (vol->vol_flags & VOLUME_IS_DIRTY)
1906                         es1 = es1a;
1907                 else if (vol->vol_flags & VOLUME_MODIFIED_BY_CHKDSK) {
1908                         es1 = es1b;
1909                         es2 = es2b;
1910                 } else {
1911                         es1 = es1c;
1912                         ntfs_warning(sb, "Unsupported volume flags 0x%x "
1913                                         "encountered.",
1914                                         (unsigned)le16_to_cpu(vol->vol_flags));
1915                 }
1916                 /* If a read-write mount, convert it to a read-only mount. */
1917                 if (!sb_rdonly(sb)) {
1918                         if (!(vol->on_errors & (ON_ERRORS_REMOUNT_RO |
1919                                         ON_ERRORS_CONTINUE))) {
1920                                 ntfs_error(sb, "%s and neither on_errors="
1921                                                 "continue nor on_errors="
1922                                                 "remount-ro was specified%s",
1923                                                 es1, es2);
1924                                 goto iput_vol_err_out;
1925                         }
1926                         sb->s_flags |= SB_RDONLY;
1927                         ntfs_error(sb, "%s.  Mounting read-only%s", es1, es2);
1928                 } else
1929                         ntfs_warning(sb, "%s.  Will not be able to remount "
1930                                         "read-write%s", es1, es2);
1931                 /*
1932                  * Do not set NVolErrors() because ntfs_remount() re-checks the
1933                  * flags which we need to do in case any flags have changed.
1934                  */
1935         }
1936         /*
1937          * Get the inode for the logfile, check it and determine if the volume
1938          * was shutdown cleanly.
1939          */
1940         rp = NULL;
1941         if (!load_and_check_logfile(vol, &rp) ||
1942                         !ntfs_is_logfile_clean(vol->logfile_ino, rp)) {
1943                 static const char *es1a = "Failed to load $LogFile";
1944                 static const char *es1b = "$LogFile is not clean";
1945                 static const char *es2 = ".  Mount in Windows.";
1946                 const char *es1;
1947 
1948                 es1 = !vol->logfile_ino ? es1a : es1b;
1949                 /* If a read-write mount, convert it to a read-only mount. */
1950                 if (!sb_rdonly(sb)) {
1951                         if (!(vol->on_errors & (ON_ERRORS_REMOUNT_RO |
1952                                         ON_ERRORS_CONTINUE))) {
1953                                 ntfs_error(sb, "%s and neither on_errors="
1954                                                 "continue nor on_errors="
1955                                                 "remount-ro was specified%s",
1956                                                 es1, es2);
1957                                 if (vol->logfile_ino) {
1958                                         BUG_ON(!rp);
1959                                         ntfs_free(rp);
1960                                 }
1961                                 goto iput_logfile_err_out;
1962                         }
1963                         sb->s_flags |= SB_RDONLY;
1964                         ntfs_error(sb, "%s.  Mounting read-only%s", es1, es2);
1965                 } else
1966                         ntfs_warning(sb, "%s.  Will not be able to remount "
1967                                         "read-write%s", es1, es2);
1968                 /* This will prevent a read-write remount. */
1969                 NVolSetErrors(vol);
1970         }
1971         ntfs_free(rp);
1972 #endif /* NTFS_RW */
1973         /* Get the root directory inode so we can do path lookups. */
1974         vol->root_ino = ntfs_iget(sb, FILE_root);
1975         if (IS_ERR(vol->root_ino) || is_bad_inode(vol->root_ino)) {
1976                 if (!IS_ERR(vol->root_ino))
1977                         iput(vol->root_ino);
1978                 ntfs_error(sb, "Failed to load root directory.");
1979                 goto iput_logfile_err_out;
1980         }
1981 #ifdef NTFS_RW
1982         /*
1983          * Check if Windows is suspended to disk on the target volume.  If it
1984          * is hibernated, we must not write *anything* to the disk so set
1985          * NVolErrors() without setting the dirty volume flag and mount
1986          * read-only.  This will prevent read-write remounting and it will also
1987          * prevent all writes.
1988          */
1989         err = check_windows_hibernation_status(vol);
1990         if (unlikely(err)) {
1991                 static const char *es1a = "Failed to determine if Windows is "
1992                                 "hibernated";
1993                 static const char *es1b = "Windows is hibernated";
1994                 static const char *es2 = ".  Run chkdsk.";
1995                 const char *es1;
1996 
1997                 es1 = err < 0 ? es1a : es1b;
1998                 /* If a read-write mount, convert it to a read-only mount. */
1999                 if (!sb_rdonly(sb)) {
2000                         if (!(vol->on_errors & (ON_ERRORS_REMOUNT_RO |
2001                                         ON_ERRORS_CONTINUE))) {
2002                                 ntfs_error(sb, "%s and neither on_errors="
2003                                                 "continue nor on_errors="
2004                                                 "remount-ro was specified%s",
2005                                                 es1, es2);
2006                                 goto iput_root_err_out;
2007                         }
2008                         sb->s_flags |= SB_RDONLY;
2009                         ntfs_error(sb, "%s.  Mounting read-only%s", es1, es2);
2010                 } else
2011                         ntfs_warning(sb, "%s.  Will not be able to remount "
2012                                         "read-write%s", es1, es2);
2013                 /* This will prevent a read-write remount. */
2014                 NVolSetErrors(vol);
2015         }
2016         /* If (still) a read-write mount, mark the volume dirty. */
2017         if (!sb_rdonly(sb) && ntfs_set_volume_flags(vol, VOLUME_IS_DIRTY)) {
2018                 static const char *es1 = "Failed to set dirty bit in volume "
2019                                 "information flags";
2020                 static const char *es2 = ".  Run chkdsk.";
2021 
2022                 /* Convert to a read-only mount. */
2023                 if (!(vol->on_errors & (ON_ERRORS_REMOUNT_RO |
2024                                 ON_ERRORS_CONTINUE))) {
2025                         ntfs_error(sb, "%s and neither on_errors=continue nor "
2026                                         "on_errors=remount-ro was specified%s",
2027                                         es1, es2);
2028                         goto iput_root_err_out;
2029                 }
2030                 ntfs_error(sb, "%s.  Mounting read-only%s", es1, es2);
2031                 sb->s_flags |= SB_RDONLY;
2032                 /*
2033                  * Do not set NVolErrors() because ntfs_remount() might manage
2034                  * to set the dirty flag in which case all would be well.
2035                  */
2036         }
2037 #if 0
2038         // TODO: Enable this code once we start modifying anything that is
2039         //       different between NTFS 1.2 and 3.x...
2040         /*
2041          * If (still) a read-write mount, set the NT4 compatibility flag on
2042          * newer NTFS version volumes.
2043          */
2044         if (!(sb->s_flags & SB_RDONLY) && (vol->major_ver > 1) &&
2045                         ntfs_set_volume_flags(vol, VOLUME_MOUNTED_ON_NT4)) {
2046                 static const char *es1 = "Failed to set NT4 compatibility flag";
2047                 static const char *es2 = ".  Run chkdsk.";
2048 
2049                 /* Convert to a read-only mount. */
2050                 if (!(vol->on_errors & (ON_ERRORS_REMOUNT_RO |
2051                                 ON_ERRORS_CONTINUE))) {
2052                         ntfs_error(sb, "%s and neither on_errors=continue nor "
2053                                         "on_errors=remount-ro was specified%s",
2054                                         es1, es2);
2055                         goto iput_root_err_out;
2056                 }
2057                 ntfs_error(sb, "%s.  Mounting read-only%s", es1, es2);
2058                 sb->s_flags |= SB_RDONLY;
2059                 NVolSetErrors(vol);
2060         }
2061 #endif
2062         /* If (still) a read-write mount, empty the logfile. */
2063         if (!sb_rdonly(sb) && !ntfs_empty_logfile(vol->logfile_ino)) {
2064                 static const char *es1 = "Failed to empty $LogFile";
2065                 static const char *es2 = ".  Mount in Windows.";
2066 
2067                 /* Convert to a read-only mount. */
2068                 if (!(vol->on_errors & (ON_ERRORS_REMOUNT_RO |
2069                                 ON_ERRORS_CONTINUE))) {
2070                         ntfs_error(sb, "%s and neither on_errors=continue nor "
2071                                         "on_errors=remount-ro was specified%s",
2072                                         es1, es2);
2073                         goto iput_root_err_out;
2074                 }
2075                 ntfs_error(sb, "%s.  Mounting read-only%s", es1, es2);
2076                 sb->s_flags |= SB_RDONLY;
2077                 NVolSetErrors(vol);
2078         }
2079 #endif /* NTFS_RW */
2080         /* If on NTFS versions before 3.0, we are done. */
2081         if (unlikely(vol->major_ver < 3))
2082                 return true;
2083         /* NTFS 3.0+ specific initialization. */
2084         /* Get the security descriptors inode. */
2085         vol->secure_ino = ntfs_iget(sb, FILE_Secure);
2086         if (IS_ERR(vol->secure_ino) || is_bad_inode(vol->secure_ino)) {
2087                 if (!IS_ERR(vol->secure_ino))
2088                         iput(vol->secure_ino);
2089                 ntfs_error(sb, "Failed to load $Secure.");
2090                 goto iput_root_err_out;
2091         }
2092         // TODO: Initialize security.
2093         /* Get the extended system files' directory inode. */
2094         vol->extend_ino = ntfs_iget(sb, FILE_Extend);
2095         if (IS_ERR(vol->extend_ino) || is_bad_inode(vol->extend_ino)) {
2096                 if (!IS_ERR(vol->extend_ino))
2097                         iput(vol->extend_ino);
2098                 ntfs_error(sb, "Failed to load $Extend.");
2099                 goto iput_sec_err_out;
2100         }
2101 #ifdef NTFS_RW
2102         /* Find the quota file, load it if present, and set it up. */
2103         if (!load_and_init_quota(vol)) {
2104                 static const char *es1 = "Failed to load $Quota";
2105                 static const char *es2 = ".  Run chkdsk.";
2106 
2107                 /* If a read-write mount, convert it to a read-only mount. */
2108                 if (!sb_rdonly(sb)) {
2109                         if (!(vol->on_errors & (ON_ERRORS_REMOUNT_RO |
2110                                         ON_ERRORS_CONTINUE))) {
2111                                 ntfs_error(sb, "%s and neither on_errors="
2112                                                 "continue nor on_errors="
2113                                                 "remount-ro was specified%s",
2114                                                 es1, es2);
2115                                 goto iput_quota_err_out;
2116                         }
2117                         sb->s_flags |= SB_RDONLY;
2118                         ntfs_error(sb, "%s.  Mounting read-only%s", es1, es2);
2119                 } else
2120                         ntfs_warning(sb, "%s.  Will not be able to remount "
2121                                         "read-write%s", es1, es2);
2122                 /* This will prevent a read-write remount. */
2123                 NVolSetErrors(vol);
2124         }
2125         /* If (still) a read-write mount, mark the quotas out of date. */
2126         if (!sb_rdonly(sb) && !ntfs_mark_quotas_out_of_date(vol)) {
2127                 static const char *es1 = "Failed to mark quotas out of date";
2128                 static const char *es2 = ".  Run chkdsk.";
2129 
2130                 /* Convert to a read-only mount. */
2131                 if (!(vol->on_errors & (ON_ERRORS_REMOUNT_RO |
2132                                 ON_ERRORS_CONTINUE))) {
2133                         ntfs_error(sb, "%s and neither on_errors=continue nor "
2134                                         "on_errors=remount-ro was specified%s",
2135                                         es1, es2);
2136                         goto iput_quota_err_out;
2137                 }
2138                 ntfs_error(sb, "%s.  Mounting read-only%s", es1, es2);
2139                 sb->s_flags |= SB_RDONLY;
2140                 NVolSetErrors(vol);
2141         }
2142         /*
2143          * Find the transaction log file ($UsnJrnl), load it if present, check
2144          * it, and set it up.
2145          */
2146         if (!load_and_init_usnjrnl(vol)) {
2147                 static const char *es1 = "Failed to load $UsnJrnl";
2148                 static const char *es2 = ".  Run chkdsk.";
2149 
2150                 /* If a read-write mount, convert it to a read-only mount. */
2151                 if (!sb_rdonly(sb)) {
2152                         if (!(vol->on_errors & (ON_ERRORS_REMOUNT_RO |
2153                                         ON_ERRORS_CONTINUE))) {
2154                                 ntfs_error(sb, "%s and neither on_errors="
2155                                                 "continue nor on_errors="
2156                                                 "remount-ro was specified%s",
2157                                                 es1, es2);
2158                                 goto iput_usnjrnl_err_out;
2159                         }
2160                         sb->s_flags |= SB_RDONLY;
2161                         ntfs_error(sb, "%s.  Mounting read-only%s", es1, es2);
2162                 } else
2163                         ntfs_warning(sb, "%s.  Will not be able to remount "
2164                                         "read-write%s", es1, es2);
2165                 /* This will prevent a read-write remount. */
2166                 NVolSetErrors(vol);
2167         }
2168         /* If (still) a read-write mount, stamp the transaction log. */
2169         if (!sb_rdonly(sb) && !ntfs_stamp_usnjrnl(vol)) {
2170                 static const char *es1 = "Failed to stamp transaction log "
2171                                 "($UsnJrnl)";
2172                 static const char *es2 = ".  Run chkdsk.";
2173 
2174                 /* Convert to a read-only mount. */
2175                 if (!(vol->on_errors & (ON_ERRORS_REMOUNT_RO |
2176                                 ON_ERRORS_CONTINUE))) {
2177                         ntfs_error(sb, "%s and neither on_errors=continue nor "
2178                                         "on_errors=remount-ro was specified%s",
2179                                         es1, es2);
2180                         goto iput_usnjrnl_err_out;
2181                 }
2182                 ntfs_error(sb, "%s.  Mounting read-only%s", es1, es2);
2183                 sb->s_flags |= SB_RDONLY;
2184                 NVolSetErrors(vol);
2185         }
2186 #endif /* NTFS_RW */
2187         return true;
2188 #ifdef NTFS_RW
2189 iput_usnjrnl_err_out:
2190         iput(vol->usnjrnl_j_ino);
2191         iput(vol->usnjrnl_max_ino);
2192         iput(vol->usnjrnl_ino);
2193 iput_quota_err_out:
2194         iput(vol->quota_q_ino);
2195         iput(vol->quota_ino);
2196         iput(vol->extend_ino);
2197 #endif /* NTFS_RW */
2198 iput_sec_err_out:
2199         iput(vol->secure_ino);
2200 iput_root_err_out:
2201         iput(vol->root_ino);
2202 iput_logfile_err_out:
2203 #ifdef NTFS_RW
2204         iput(vol->logfile_ino);
2205 iput_vol_err_out:
2206 #endif /* NTFS_RW */
2207         iput(vol->vol_ino);
2208 iput_lcnbmp_err_out:
2209         iput(vol->lcnbmp_ino);
2210 iput_attrdef_err_out:
2211         vol->attrdef_size = 0;
2212         if (vol->attrdef) {
2213                 ntfs_free(vol->attrdef);
2214                 vol->attrdef = NULL;
2215         }
2216 #ifdef NTFS_RW
2217 iput_upcase_err_out:
2218 #endif /* NTFS_RW */
2219         vol->upcase_len = 0;
2220         mutex_lock(&ntfs_lock);
2221         if (vol->upcase == default_upcase) {
2222                 ntfs_nr_upcase_users--;
2223                 vol->upcase = NULL;
2224         }
2225         mutex_unlock(&ntfs_lock);
2226         if (vol->upcase) {
2227                 ntfs_free(vol->upcase);
2228                 vol->upcase = NULL;
2229         }
2230 iput_mftbmp_err_out:
2231         iput(vol->mftbmp_ino);
2232 iput_mirr_err_out:
2233 #ifdef NTFS_RW
2234         iput(vol->mftmirr_ino);
2235 #endif /* NTFS_RW */
2236         return false;
2237 }
2238 
2239 /**
2240  * ntfs_put_super - called by the vfs to unmount a volume
2241  * @sb:         vfs superblock of volume to unmount
2242  *
2243  * ntfs_put_super() is called by the VFS (from fs/super.c::do_umount()) when
2244  * the volume is being unmounted (umount system call has been invoked) and it
2245  * releases all inodes and memory belonging to the NTFS specific part of the
2246  * super block.
2247  */
2248 static void ntfs_put_super(struct super_block *sb)
2249 {
2250         ntfs_volume *vol = NTFS_SB(sb);
2251 
2252         ntfs_debug("Entering.");
2253 
2254 #ifdef NTFS_RW
2255         /*
2256          * Commit all inodes while they are still open in case some of them
2257          * cause others to be dirtied.
2258          */
2259         ntfs_commit_inode(vol->vol_ino);
2260 
2261         /* NTFS 3.0+ specific. */
2262         if (vol->major_ver >= 3) {
2263                 if (vol->usnjrnl_j_ino)
2264                         ntfs_commit_inode(vol->usnjrnl_j_ino);
2265                 if (vol->usnjrnl_max_ino)
2266                         ntfs_commit_inode(vol->usnjrnl_max_ino);
2267                 if (vol->usnjrnl_ino)
2268                         ntfs_commit_inode(vol->usnjrnl_ino);
2269                 if (vol->quota_q_ino)
2270                         ntfs_commit_inode(vol->quota_q_ino);
2271                 if (vol->quota_ino)
2272                         ntfs_commit_inode(vol->quota_ino);
2273                 if (vol->extend_ino)
2274                         ntfs_commit_inode(vol->extend_ino);
2275                 if (vol->secure_ino)
2276                         ntfs_commit_inode(vol->secure_ino);
2277         }
2278 
2279         ntfs_commit_inode(vol->root_ino);
2280 
2281         down_write(&vol->lcnbmp_lock);
2282         ntfs_commit_inode(vol->lcnbmp_ino);
2283         up_write(&vol->lcnbmp_lock);
2284 
2285         down_write(&vol->mftbmp_lock);
2286         ntfs_commit_inode(vol->mftbmp_ino);
2287         up_write(&vol->mftbmp_lock);
2288 
2289         if (vol->logfile_ino)
2290                 ntfs_commit_inode(vol->logfile_ino);
2291 
2292         if (vol->mftmirr_ino)
2293                 ntfs_commit_inode(vol->mftmirr_ino);
2294         ntfs_commit_inode(vol->mft_ino);
2295 
2296         /*
2297          * If a read-write mount and no volume errors have occurred, mark the
2298          * volume clean.  Also, re-commit all affected inodes.
2299          */
2300         if (!sb_rdonly(sb)) {
2301                 if (!NVolErrors(vol)) {
2302                         if (ntfs_clear_volume_flags(vol, VOLUME_IS_DIRTY))
2303                                 ntfs_warning(sb, "Failed to clear dirty bit "
2304                                                 "in volume information "
2305                                                 "flags.  Run chkdsk.");
2306                         ntfs_commit_inode(vol->vol_ino);
2307                         ntfs_commit_inode(vol->root_ino);
2308                         if (vol->mftmirr_ino)
2309                                 ntfs_commit_inode(vol->mftmirr_ino);
2310                         ntfs_commit_inode(vol->mft_ino);
2311                 } else {
2312                         ntfs_warning(sb, "Volume has errors.  Leaving volume "
2313                                         "marked dirty.  Run chkdsk.");
2314                 }
2315         }
2316 #endif /* NTFS_RW */
2317 
2318         iput(vol->vol_ino);
2319         vol->vol_ino = NULL;
2320 
2321         /* NTFS 3.0+ specific clean up. */
2322         if (vol->major_ver >= 3) {
2323 #ifdef NTFS_RW
2324                 if (vol->usnjrnl_j_ino) {
2325                         iput(vol->usnjrnl_j_ino);
2326                         vol->usnjrnl_j_ino = NULL;
2327                 }
2328                 if (vol->usnjrnl_max_ino) {
2329                         iput(vol->usnjrnl_max_ino);
2330                         vol->usnjrnl_max_ino = NULL;
2331                 }
2332                 if (vol->usnjrnl_ino) {
2333                         iput(vol->usnjrnl_ino);
2334                         vol->usnjrnl_ino = NULL;
2335                 }
2336                 if (vol->quota_q_ino) {
2337                         iput(vol->quota_q_ino);
2338                         vol->quota_q_ino = NULL;
2339                 }
2340                 if (vol->quota_ino) {
2341                         iput(vol->quota_ino);
2342                         vol->quota_ino = NULL;
2343                 }
2344 #endif /* NTFS_RW */
2345                 if (vol->extend_ino) {
2346                         iput(vol->extend_ino);
2347                         vol->extend_ino = NULL;
2348                 }
2349                 if (vol->secure_ino) {
2350                         iput(vol->secure_ino);
2351                         vol->secure_ino = NULL;
2352                 }
2353         }
2354 
2355         iput(vol->root_ino);
2356         vol->root_ino = NULL;
2357 
2358         down_write(&vol->lcnbmp_lock);
2359         iput(vol->lcnbmp_ino);
2360         vol->lcnbmp_ino = NULL;
2361         up_write(&vol->lcnbmp_lock);
2362 
2363         down_write(&vol->mftbmp_lock);
2364         iput(vol->mftbmp_ino);
2365         vol->mftbmp_ino = NULL;
2366         up_write(&vol->mftbmp_lock);
2367 
2368 #ifdef NTFS_RW
2369         if (vol->logfile_ino) {
2370                 iput(vol->logfile_ino);
2371                 vol->logfile_ino = NULL;
2372         }
2373         if (vol->mftmirr_ino) {
2374                 /* Re-commit the mft mirror and mft just in case. */
2375                 ntfs_commit_inode(vol->mftmirr_ino);
2376                 ntfs_commit_inode(vol->mft_ino);
2377                 iput(vol->mftmirr_ino);
2378                 vol->mftmirr_ino = NULL;
2379         }
2380         /*
2381          * We should have no dirty inodes left, due to
2382          * mft.c::ntfs_mft_writepage() cleaning all the dirty pages as
2383          * the underlying mft records are written out and cleaned.
2384          */
2385         ntfs_commit_inode(vol->mft_ino);
2386         write_inode_now(vol->mft_ino, 1);
2387 #endif /* NTFS_RW */
2388 
2389         iput(vol->mft_ino);
2390         vol->mft_ino = NULL;
2391 
2392         /* Throw away the table of attribute definitions. */
2393         vol->attrdef_size = 0;
2394         if (vol->attrdef) {
2395                 ntfs_free(vol->attrdef);
2396                 vol->attrdef = NULL;
2397         }
2398         vol->upcase_len = 0;
2399         /*
2400          * Destroy the global default upcase table if necessary.  Also decrease
2401          * the number of upcase users if we are a user.
2402          */
2403         mutex_lock(&ntfs_lock);
2404         if (vol->upcase == default_upcase) {
2405                 ntfs_nr_upcase_users--;
2406                 vol->upcase = NULL;
2407         }
2408         if (!ntfs_nr_upcase_users && default_upcase) {
2409                 ntfs_free(default_upcase);
2410                 default_upcase = NULL;
2411         }
2412         if (vol->cluster_size <= 4096 && !--ntfs_nr_compression_users)
2413                 free_compression_buffers();
2414         mutex_unlock(&ntfs_lock);
2415         if (vol->upcase) {
2416                 ntfs_free(vol->upcase);
2417                 vol->upcase = NULL;
2418         }
2419 
2420         unload_nls(vol->nls_map);
2421 
2422         sb->s_fs_info = NULL;
2423         kfree(vol);
2424 }
2425 
2426 /**
2427  * get_nr_free_clusters - return the number of free clusters on a volume
2428  * @vol:        ntfs volume for which to obtain free cluster count
2429  *
2430  * Calculate the number of free clusters on the mounted NTFS volume @vol. We
2431  * actually calculate the number of clusters in use instead because this
2432  * allows us to not care about partial pages as these will be just zero filled
2433  * and hence not be counted as allocated clusters.
2434  *
2435  * The only particularity is that clusters beyond the end of the logical ntfs
2436  * volume will be marked as allocated to prevent errors which means we have to
2437  * discount those at the end. This is important as the cluster bitmap always
2438  * has a size in multiples of 8 bytes, i.e. up to 63 clusters could be outside
2439  * the logical volume and marked in use when they are not as they do not exist.
2440  *
2441  * If any pages cannot be read we assume all clusters in the erroring pages are
2442  * in use. This means we return an underestimate on errors which is better than
2443  * an overestimate.
2444  */
2445 static s64 get_nr_free_clusters(ntfs_volume *vol)
2446 {
2447         s64 nr_free = vol->nr_clusters;
2448         struct address_space *mapping = vol->lcnbmp_ino->i_mapping;
2449         struct page *page;
2450         pgoff_t index, max_index;
2451 
2452         ntfs_debug("Entering.");
2453         /* Serialize accesses to the cluster bitmap. */
2454         down_read(&vol->lcnbmp_lock);
2455         /*
2456          * Convert the number of bits into bytes rounded up, then convert into
2457          * multiples of PAGE_SIZE, rounding up so that if we have one
2458          * full and one partial page max_index = 2.
2459          */
2460         max_index = (((vol->nr_clusters + 7) >> 3) + PAGE_SIZE - 1) >>
2461                         PAGE_SHIFT;
2462         /* Use multiples of 4 bytes, thus max_size is PAGE_SIZE / 4. */
2463         ntfs_debug("Reading $Bitmap, max_index = 0x%lx, max_size = 0x%lx.",
2464                         max_index, PAGE_SIZE / 4);
2465         for (index = 0; index < max_index; index++) {
2466                 unsigned long *kaddr;
2467 
2468                 /*
2469                  * Read the page from page cache, getting it from backing store
2470                  * if necessary, and increment the use count.
2471                  */
2472                 page = read_mapping_page(mapping, index, NULL);
2473                 /* Ignore pages which errored synchronously. */
2474                 if (IS_ERR(page)) {
2475                         ntfs_debug("read_mapping_page() error. Skipping "
2476                                         "page (index 0x%lx).", index);
2477                         nr_free -= PAGE_SIZE * 8;
2478                         continue;
2479                 }
2480                 kaddr = kmap_atomic(page);
2481                 /*
2482                  * Subtract the number of set bits. If this
2483                  * is the last page and it is partial we don't really care as
2484                  * it just means we do a little extra work but it won't affect
2485                  * the result as all out of range bytes are set to zero by
2486                  * ntfs_readpage().
2487                  */
2488                 nr_free -= bitmap_weight(kaddr,
2489                                         PAGE_SIZE * BITS_PER_BYTE);
2490                 kunmap_atomic(kaddr);
2491                 put_page(page);
2492         }
2493         ntfs_debug("Finished reading $Bitmap, last index = 0x%lx.", index - 1);
2494         /*
2495          * Fixup for eventual bits outside logical ntfs volume (see function
2496          * description above).
2497          */
2498         if (vol->nr_clusters & 63)
2499                 nr_free += 64 - (vol->nr_clusters & 63);
2500         up_read(&vol->lcnbmp_lock);
2501         /* If errors occurred we may well have gone below zero, fix this. */
2502         if (nr_free < 0)
2503                 nr_free = 0;
2504         ntfs_debug("Exiting.");
2505         return nr_free;
2506 }
2507 
2508 /**
2509  * __get_nr_free_mft_records - return the number of free inodes on a volume
2510  * @vol:        ntfs volume for which to obtain free inode count
2511  * @nr_free:    number of mft records in filesystem
2512  * @max_index:  maximum number of pages containing set bits
2513  *
2514  * Calculate the number of free mft records (inodes) on the mounted NTFS
2515  * volume @vol. We actually calculate the number of mft records in use instead
2516  * because this allows us to not care about partial pages as these will be just
2517  * zero filled and hence not be counted as allocated mft record.
2518  *
2519  * If any pages cannot be read we assume all mft records in the erroring pages
2520  * are in use. This means we return an underestimate on errors which is better
2521  * than an overestimate.
2522  *
2523  * NOTE: Caller must hold mftbmp_lock rw_semaphore for reading or writing.
2524  */
2525 static unsigned long __get_nr_free_mft_records(ntfs_volume *vol,
2526                 s64 nr_free, const pgoff_t max_index)
2527 {
2528         struct address_space *mapping = vol->mftbmp_ino->i_mapping;
2529         struct page *page;
2530         pgoff_t index;
2531 
2532         ntfs_debug("Entering.");
2533         /* Use multiples of 4 bytes, thus max_size is PAGE_SIZE / 4. */
2534         ntfs_debug("Reading $MFT/$BITMAP, max_index = 0x%lx, max_size = "
2535                         "0x%lx.", max_index, PAGE_SIZE / 4);
2536         for (index = 0; index < max_index; index++) {
2537                 unsigned long *kaddr;
2538 
2539                 /*
2540                  * Read the page from page cache, getting it from backing store
2541                  * if necessary, and increment the use count.
2542                  */
2543                 page = read_mapping_page(mapping, index, NULL);
2544                 /* Ignore pages which errored synchronously. */
2545                 if (IS_ERR(page)) {
2546                         ntfs_debug("read_mapping_page() error. Skipping "
2547                                         "page (index 0x%lx).", index);
2548                         nr_free -= PAGE_SIZE * 8;
2549                         continue;
2550                 }
2551                 kaddr = kmap_atomic(page);
2552                 /*
2553                  * Subtract the number of set bits. If this
2554                  * is the last page and it is partial we don't really care as
2555                  * it just means we do a little extra work but it won't affect
2556                  * the result as all out of range bytes are set to zero by
2557                  * ntfs_readpage().
2558                  */
2559                 nr_free -= bitmap_weight(kaddr,
2560                                         PAGE_SIZE * BITS_PER_BYTE);
2561                 kunmap_atomic(kaddr);
2562                 put_page(page);
2563         }
2564         ntfs_debug("Finished reading $MFT/$BITMAP, last index = 0x%lx.",
2565                         index - 1);
2566         /* If errors occurred we may well have gone below zero, fix this. */
2567         if (nr_free < 0)
2568                 nr_free = 0;
2569         ntfs_debug("Exiting.");
2570         return nr_free;
2571 }
2572 
2573 /**
2574  * ntfs_statfs - return information about mounted NTFS volume
2575  * @dentry:     dentry from mounted volume
2576  * @sfs:        statfs structure in which to return the information
2577  *
2578  * Return information about the mounted NTFS volume @dentry in the statfs structure
2579  * pointed to by @sfs (this is initialized with zeros before ntfs_statfs is
2580  * called). We interpret the values to be correct of the moment in time at
2581  * which we are called. Most values are variable otherwise and this isn't just
2582  * the free values but the totals as well. For example we can increase the
2583  * total number of file nodes if we run out and we can keep doing this until
2584  * there is no more space on the volume left at all.
2585  *
2586  * Called from vfs_statfs which is used to handle the statfs, fstatfs, and
2587  * ustat system calls.
2588  *
2589  * Return 0 on success or -errno on error.
2590  */
2591 static int ntfs_statfs(struct dentry *dentry, struct kstatfs *sfs)
2592 {
2593         struct super_block *sb = dentry->d_sb;
2594         s64 size;
2595         ntfs_volume *vol = NTFS_SB(sb);
2596         ntfs_inode *mft_ni = NTFS_I(vol->mft_ino);
2597         pgoff_t max_index;
2598         unsigned long flags;
2599 
2600         ntfs_debug("Entering.");
2601         /* Type of filesystem. */
2602         sfs->f_type   = NTFS_SB_MAGIC;
2603         /* Optimal transfer block size. */
2604         sfs->f_bsize  = PAGE_SIZE;
2605         /*
2606          * Total data blocks in filesystem in units of f_bsize and since
2607          * inodes are also stored in data blocs ($MFT is a file) this is just
2608          * the total clusters.
2609          */
2610         sfs->f_blocks = vol->nr_clusters << vol->cluster_size_bits >>
2611                                 PAGE_SHIFT;
2612         /* Free data blocks in filesystem in units of f_bsize. */
2613         size          = get_nr_free_clusters(vol) << vol->cluster_size_bits >>
2614                                 PAGE_SHIFT;
2615         if (size < 0LL)
2616                 size = 0LL;
2617         /* Free blocks avail to non-superuser, same as above on NTFS. */
2618         sfs->f_bavail = sfs->f_bfree = size;
2619         /* Serialize accesses to the inode bitmap. */
2620         down_read(&vol->mftbmp_lock);
2621         read_lock_irqsave(&mft_ni->size_lock, flags);
2622         size = i_size_read(vol->mft_ino) >> vol->mft_record_size_bits;
2623         /*
2624          * Convert the maximum number of set bits into bytes rounded up, then
2625          * convert into multiples of PAGE_SIZE, rounding up so that if we
2626          * have one full and one partial page max_index = 2.
2627          */
2628         max_index = ((((mft_ni->initialized_size >> vol->mft_record_size_bits)
2629                         + 7) >> 3) + PAGE_SIZE - 1) >> PAGE_SHIFT;
2630         read_unlock_irqrestore(&mft_ni->size_lock, flags);
2631         /* Number of inodes in filesystem (at this point in time). */
2632         sfs->f_files = size;
2633         /* Free inodes in fs (based on current total count). */
2634         sfs->f_ffree = __get_nr_free_mft_records(vol, size, max_index);
2635         up_read(&vol->mftbmp_lock);
2636         /*
2637          * File system id. This is extremely *nix flavour dependent and even
2638          * within Linux itself all fs do their own thing. I interpret this to
2639          * mean a unique id associated with the mounted fs and not the id
2640          * associated with the filesystem driver, the latter is already given
2641          * by the filesystem type in sfs->f_type. Thus we use the 64-bit
2642          * volume serial number splitting it into two 32-bit parts. We enter
2643          * the least significant 32-bits in f_fsid[0] and the most significant
2644          * 32-bits in f_fsid[1].
2645          */
2646         sfs->f_fsid.val[0] = vol->serial_no & 0xffffffff;
2647         sfs->f_fsid.val[1] = (vol->serial_no >> 32) & 0xffffffff;
2648         /* Maximum length of filenames. */
2649         sfs->f_namelen     = NTFS_MAX_NAME_LEN;
2650         return 0;
2651 }
2652 
2653 #ifdef NTFS_RW
2654 static int ntfs_write_inode(struct inode *vi, struct writeback_control *wbc)
2655 {
2656         return __ntfs_write_inode(vi, wbc->sync_mode == WB_SYNC_ALL);
2657 }
2658 #endif
2659 
2660 /**
2661  * The complete super operations.
2662  */
2663 static const struct super_operations ntfs_sops = {
2664         .alloc_inode    = ntfs_alloc_big_inode,   /* VFS: Allocate new inode. */
2665         .free_inode     = ntfs_free_big_inode, /* VFS: Deallocate inode. */
2666 #ifdef NTFS_RW
2667         .write_inode    = ntfs_write_inode,     /* VFS: Write dirty inode to
2668                                                    disk. */
2669 #endif /* NTFS_RW */
2670         .put_super      = ntfs_put_super,       /* Syscall: umount. */
2671         .statfs         = ntfs_statfs,          /* Syscall: statfs */
2672         .remount_fs     = ntfs_remount,         /* Syscall: mount -o remount. */
2673         .evict_inode    = ntfs_evict_big_inode, /* VFS: Called when an inode is
2674                                                    removed from memory. */
2675         .show_options   = ntfs_show_options,    /* Show mount options in
2676                                                    proc. */
2677 };
2678 
2679 /**
2680  * ntfs_fill_super - mount an ntfs filesystem
2681  * @sb:         super block of ntfs filesystem to mount
2682  * @opt:        string containing the mount options
2683  * @silent:     silence error output
2684  *
2685  * ntfs_fill_super() is called by the VFS to mount the device described by @sb
2686  * with the mount otions in @data with the NTFS filesystem.
2687  *
2688  * If @silent is true, remain silent even if errors are detected. This is used
2689  * during bootup, when the kernel tries to mount the root filesystem with all
2690  * registered filesystems one after the other until one succeeds. This implies
2691  * that all filesystems except the correct one will quite correctly and
2692  * expectedly return an error, but nobody wants to see error messages when in
2693  * fact this is what is supposed to happen.
2694  *
2695  * NOTE: @sb->s_flags contains the mount options flags.
2696  */
2697 static int ntfs_fill_super(struct super_block *sb, void *opt, const int silent)
2698 {
2699         ntfs_volume *vol;
2700         struct buffer_head *bh;
2701         struct inode *tmp_ino;
2702         int blocksize, result;
2703 
2704         /*
2705          * We do a pretty difficult piece of bootstrap by reading the
2706          * MFT (and other metadata) from disk into memory. We'll only
2707          * release this metadata during umount, so the locking patterns
2708          * observed during bootstrap do not count. So turn off the
2709          * observation of locking patterns (strictly for this context
2710          * only) while mounting NTFS. [The validator is still active
2711          * otherwise, even for this context: it will for example record
2712          * lock class registrations.]
2713          */
2714         lockdep_off();
2715         ntfs_debug("Entering.");
2716 #ifndef NTFS_RW
2717         sb->s_flags |= SB_RDONLY;
2718 #endif /* ! NTFS_RW */
2719         /* Allocate a new ntfs_volume and place it in sb->s_fs_info. */
2720         sb->s_fs_info = kmalloc(sizeof(ntfs_volume), GFP_NOFS);
2721         vol = NTFS_SB(sb);
2722         if (!vol) {
2723                 if (!silent)
2724                         ntfs_error(sb, "Allocation of NTFS volume structure "
2725                                         "failed. Aborting mount...");
2726                 lockdep_on();
2727                 return -ENOMEM;
2728         }
2729         /* Initialize ntfs_volume structure. */
2730         *vol = (ntfs_volume) {
2731                 .sb = sb,
2732                 /*
2733                  * Default is group and other don't have any access to files or
2734                  * directories while owner has full access. Further, files by
2735                  * default are not executable but directories are of course
2736                  * browseable.
2737                  */
2738                 .fmask = 0177,
2739                 .dmask = 0077,
2740         };
2741         init_rwsem(&vol->mftbmp_lock);
2742         init_rwsem(&vol->lcnbmp_lock);
2743 
2744         /* By default, enable sparse support. */
2745         NVolSetSparseEnabled(vol);
2746 
2747         /* Important to get the mount options dealt with now. */
2748         if (!parse_options(vol, (char*)opt))
2749                 goto err_out_now;
2750 
2751         /* We support sector sizes up to the PAGE_SIZE. */
2752         if (bdev_logical_block_size(sb->s_bdev) > PAGE_SIZE) {
2753                 if (!silent)
2754                         ntfs_error(sb, "Device has unsupported sector size "
2755                                         "(%i).  The maximum supported sector "
2756                                         "size on this architecture is %lu "
2757                                         "bytes.",
2758                                         bdev_logical_block_size(sb->s_bdev),
2759                                         PAGE_SIZE);
2760                 goto err_out_now;
2761         }
2762         /*
2763          * Setup the device access block size to NTFS_BLOCK_SIZE or the hard
2764          * sector size, whichever is bigger.
2765          */
2766         blocksize = sb_min_blocksize(sb, NTFS_BLOCK_SIZE);
2767         if (blocksize < NTFS_BLOCK_SIZE) {
2768                 if (!silent)
2769                         ntfs_error(sb, "Unable to set device block size.");
2770                 goto err_out_now;
2771         }
2772         BUG_ON(blocksize != sb->s_blocksize);
2773         ntfs_debug("Set device block size to %i bytes (block size bits %i).",
2774                         blocksize, sb->s_blocksize_bits);
2775         /* Determine the size of the device in units of block_size bytes. */
2776         if (!i_size_read(sb->s_bdev->bd_inode)) {
2777                 if (!silent)
2778                         ntfs_error(sb, "Unable to determine device size.");
2779                 goto err_out_now;
2780         }
2781         vol->nr_blocks = i_size_read(sb->s_bdev->bd_inode) >>
2782                         sb->s_blocksize_bits;
2783         /* Read the boot sector and return unlocked buffer head to it. */
2784         if (!(bh = read_ntfs_boot_sector(sb, silent))) {
2785                 if (!silent)
2786                         ntfs_error(sb, "Not an NTFS volume.");
2787                 goto err_out_now;
2788         }
2789         /*
2790          * Extract the data from the boot sector and setup the ntfs volume
2791          * using it.
2792          */
2793         result = parse_ntfs_boot_sector(vol, (NTFS_BOOT_SECTOR*)bh->b_data);
2794         brelse(bh);
2795         if (!result) {
2796                 if (!silent)
2797                         ntfs_error(sb, "Unsupported NTFS filesystem.");
2798                 goto err_out_now;
2799         }
2800         /*
2801          * If the boot sector indicates a sector size bigger than the current
2802          * device block size, switch the device block size to the sector size.
2803          * TODO: It may be possible to support this case even when the set
2804          * below fails, we would just be breaking up the i/o for each sector
2805          * into multiple blocks for i/o purposes but otherwise it should just
2806          * work.  However it is safer to leave disabled until someone hits this
2807          * error message and then we can get them to try it without the setting
2808          * so we know for sure that it works.
2809          */
2810         if (vol->sector_size > blocksize) {
2811                 blocksize = sb_set_blocksize(sb, vol->sector_size);
2812                 if (blocksize != vol->sector_size) {
2813                         if (!silent)
2814                                 ntfs_error(sb, "Unable to set device block "
2815                                                 "size to sector size (%i).",
2816                                                 vol->sector_size);
2817                         goto err_out_now;
2818                 }
2819                 BUG_ON(blocksize != sb->s_blocksize);
2820                 vol->nr_blocks = i_size_read(sb->s_bdev->bd_inode) >>
2821                                 sb->s_blocksize_bits;
2822                 ntfs_debug("Changed device block size to %i bytes (block size "
2823                                 "bits %i) to match volume sector size.",
2824                                 blocksize, sb->s_blocksize_bits);
2825         }
2826         /* Initialize the cluster and mft allocators. */
2827         ntfs_setup_allocators(vol);
2828         /* Setup remaining fields in the super block. */
2829         sb->s_magic = NTFS_SB_MAGIC;
2830         /*
2831          * Ntfs allows 63 bits for the file size, i.e. correct would be:
2832          *      sb->s_maxbytes = ~0ULL >> 1;
2833          * But the kernel uses a long as the page cache page index which on
2834          * 32-bit architectures is only 32-bits. MAX_LFS_FILESIZE is kernel
2835          * defined to the maximum the page cache page index can cope with
2836          * without overflowing the index or to 2^63 - 1, whichever is smaller.
2837          */
2838         sb->s_maxbytes = MAX_LFS_FILESIZE;
2839         /* Ntfs measures time in 100ns intervals. */
2840         sb->s_time_gran = 100;
2841         /*
2842          * Now load the metadata required for the page cache and our address
2843          * space operations to function. We do this by setting up a specialised
2844          * read_inode method and then just calling the normal iget() to obtain
2845          * the inode for $MFT which is sufficient to allow our normal inode
2846          * operations and associated address space operations to function.
2847          */
2848         sb->s_op = &ntfs_sops;
2849         tmp_ino = new_inode(sb);
2850         if (!tmp_ino) {
2851                 if (!silent)
2852                         ntfs_error(sb, "Failed to load essential metadata.");
2853                 goto err_out_now;
2854         }
2855         tmp_ino->i_ino = FILE_MFT;
2856         insert_inode_hash(tmp_ino);
2857         if (ntfs_read_inode_mount(tmp_ino) < 0) {
2858                 if (!silent)
2859                         ntfs_error(sb, "Failed to load essential metadata.");
2860                 goto iput_tmp_ino_err_out_now;
2861         }
2862         mutex_lock(&ntfs_lock);
2863         /*
2864          * The current mount is a compression user if the cluster size is
2865          * less than or equal 4kiB.
2866          */
2867         if (vol->cluster_size <= 4096 && !ntfs_nr_compression_users++) {
2868                 result = allocate_compression_buffers();
2869                 if (result) {
2870                         ntfs_error(NULL, "Failed to allocate buffers "
2871                                         "for compression engine.");
2872                         ntfs_nr_compression_users--;
2873                         mutex_unlock(&ntfs_lock);
2874                         goto iput_tmp_ino_err_out_now;
2875                 }
2876         }
2877         /*
2878          * Generate the global default upcase table if necessary.  Also
2879          * temporarily increment the number of upcase users to avoid race
2880          * conditions with concurrent (u)mounts.
2881          */
2882         if (!default_upcase)
2883                 default_upcase = generate_default_upcase();
2884         ntfs_nr_upcase_users++;
2885         mutex_unlock(&ntfs_lock);
2886         /*
2887          * From now on, ignore @silent parameter. If we fail below this line,
2888          * it will be due to a corrupt fs or a system error, so we report it.
2889          */
2890         /*
2891          * Open the system files with normal access functions and complete
2892          * setting up the ntfs super block.
2893          */
2894         if (!load_system_files(vol)) {
2895                 ntfs_error(sb, "Failed to load system files.");
2896                 goto unl_upcase_iput_tmp_ino_err_out_now;
2897         }
2898 
2899         /* We grab a reference, simulating an ntfs_iget(). */
2900         ihold(vol->root_ino);
2901         if ((sb->s_root = d_make_root(vol->root_ino))) {
2902                 ntfs_debug("Exiting, status successful.");
2903                 /* Release the default upcase if it has no users. */
2904                 mutex_lock(&ntfs_lock);
2905                 if (!--ntfs_nr_upcase_users && default_upcase) {
2906                         ntfs_free(default_upcase);
2907                         default_upcase = NULL;
2908                 }
2909                 mutex_unlock(&ntfs_lock);
2910                 sb->s_export_op = &ntfs_export_ops;
2911                 lockdep_on();
2912                 return 0;
2913         }
2914         ntfs_error(sb, "Failed to allocate root directory.");
2915         /* Clean up after the successful load_system_files() call from above. */
2916         // TODO: Use ntfs_put_super() instead of repeating all this code...
2917         // FIXME: Should mark the volume clean as the error is most likely
2918         //        -ENOMEM.
2919         iput(vol->vol_ino);
2920         vol->vol_ino = NULL;
2921         /* NTFS 3.0+ specific clean up. */
2922         if (vol->major_ver >= 3) {
2923 #ifdef NTFS_RW
2924                 if (vol->usnjrnl_j_ino) {
2925                         iput(vol->usnjrnl_j_ino);
2926                         vol->usnjrnl_j_ino = NULL;
2927                 }
2928                 if (vol->usnjrnl_max_ino) {
2929                         iput(vol->usnjrnl_max_ino);
2930                         vol->usnjrnl_max_ino = NULL;
2931                 }
2932                 if (vol->usnjrnl_ino) {
2933                         iput(vol->usnjrnl_ino);
2934                         vol->usnjrnl_ino = NULL;
2935                 }
2936                 if (vol->quota_q_ino) {
2937                         iput(vol->quota_q_ino);
2938                         vol->quota_q_ino = NULL;
2939                 }
2940                 if (vol->quota_ino) {
2941                         iput(vol->quota_ino);
2942                         vol->quota_ino = NULL;
2943                 }
2944 #endif /* NTFS_RW */
2945                 if (vol->extend_ino) {
2946                         iput(vol->extend_ino);
2947                         vol->extend_ino = NULL;
2948                 }
2949                 if (vol->secure_ino) {
2950                         iput(vol->secure_ino);
2951                         vol->secure_ino = NULL;
2952                 }
2953         }
2954         iput(vol->root_ino);
2955         vol->root_ino = NULL;
2956         iput(vol->lcnbmp_ino);
2957         vol->lcnbmp_ino = NULL;
2958         iput(vol->mftbmp_ino);
2959         vol->mftbmp_ino = NULL;
2960 #ifdef NTFS_RW
2961         if (vol->logfile_ino) {
2962                 iput(vol->logfile_ino);
2963                 vol->logfile_ino = NULL;
2964         }
2965         if (vol->mftmirr_ino) {
2966                 iput(vol->mftmirr_ino);
2967                 vol->mftmirr_ino = NULL;
2968         }
2969 #endif /* NTFS_RW */
2970         /* Throw away the table of attribute definitions. */
2971         vol->attrdef_size = 0;
2972         if (vol->attrdef) {
2973                 ntfs_free(vol->attrdef);
2974                 vol->attrdef = NULL;
2975         }
2976         vol->upcase_len = 0;
2977         mutex_lock(&ntfs_lock);
2978         if (vol->upcase == default_upcase) {
2979                 ntfs_nr_upcase_users--;
2980                 vol->upcase = NULL;
2981         }
2982         mutex_unlock(&ntfs_lock);
2983         if (vol->upcase) {
2984                 ntfs_free(vol->upcase);
2985                 vol->upcase = NULL;
2986         }
2987         if (vol->nls_map) {
2988                 unload_nls(vol->nls_map);
2989                 vol->nls_map = NULL;
2990         }
2991         /* Error exit code path. */
2992 unl_upcase_iput_tmp_ino_err_out_now:
2993         /*
2994          * Decrease the number of upcase users and destroy the global default
2995          * upcase table if necessary.
2996          */
2997         mutex_lock(&ntfs_lock);
2998         if (!--ntfs_nr_upcase_users && default_upcase) {
2999                 ntfs_free(default_upcase);
3000                 default_upcase = NULL;
3001         }
3002         if (vol->cluster_size <= 4096 && !--ntfs_nr_compression_users)
3003                 free_compression_buffers();
3004         mutex_unlock(&ntfs_lock);
3005 iput_tmp_ino_err_out_now:
3006         iput(tmp_ino);
3007         if (vol->mft_ino && vol->mft_ino != tmp_ino)
3008                 iput(vol->mft_ino);
3009         vol->mft_ino = NULL;
3010         /* Errors at this stage are irrelevant. */
3011 err_out_now:
3012         sb->s_fs_info = NULL;
3013         kfree(vol);
3014         ntfs_debug("Failed, returning -EINVAL.");
3015         lockdep_on();
3016         return -EINVAL;
3017 }
3018 
3019 /*
3020  * This is a slab cache to optimize allocations and deallocations of Unicode
3021  * strings of the maximum length allowed by NTFS, which is NTFS_MAX_NAME_LEN
3022  * (255) Unicode characters + a terminating NULL Unicode character.
3023  */
3024 struct kmem_cache *ntfs_name_cache;
3025 
3026 /* Slab caches for efficient allocation/deallocation of inodes. */
3027 struct kmem_cache *ntfs_inode_cache;
3028 struct kmem_cache *ntfs_big_inode_cache;
3029 
3030 /* Init once constructor for the inode slab cache. */
3031 static void ntfs_big_inode_init_once(void *foo)
3032 {
3033         ntfs_inode *ni = (ntfs_inode *)foo;
3034 
3035         inode_init_once(VFS_I(ni));
3036 }
3037 
3038 /*
3039  * Slab caches to optimize allocations and deallocations of attribute search
3040  * contexts and index contexts, respectively.
3041  */
3042 struct kmem_cache *ntfs_attr_ctx_cache;
3043 struct kmem_cache *ntfs_index_ctx_cache;
3044 
3045 /* Driver wide mutex. */
3046 DEFINE_MUTEX(ntfs_lock);
3047 
3048 static struct dentry *ntfs_mount(struct file_system_type *fs_type,
3049         int flags, const char *dev_name, void *data)
3050 {
3051         return mount_bdev(fs_type, flags, dev_name, data, ntfs_fill_super);
3052 }
3053 
3054 static struct file_system_type ntfs_fs_type = {
3055         .owner          = THIS_MODULE,
3056         .name           = "ntfs",
3057         .mount          = ntfs_mount,
3058         .kill_sb        = kill_block_super,
3059         .fs_flags       = FS_REQUIRES_DEV,
3060 };
3061 MODULE_ALIAS_FS("ntfs");
3062 
3063 /* Stable names for the slab caches. */
3064 static const char ntfs_index_ctx_cache_name[] = "ntfs_index_ctx_cache";
3065 static const char ntfs_attr_ctx_cache_name[] = "ntfs_attr_ctx_cache";
3066 static const char ntfs_name_cache_name[] = "ntfs_name_cache";
3067 static const char ntfs_inode_cache_name[] = "ntfs_inode_cache";
3068 static const char ntfs_big_inode_cache_name[] = "ntfs_big_inode_cache";
3069 
3070 static int __init init_ntfs_fs(void)
3071 {
3072         int err = 0;
3073 
3074         /* This may be ugly but it results in pretty output so who cares. (-8 */
3075         pr_info("driver " NTFS_VERSION " [Flags: R/"
3076 #ifdef NTFS_RW
3077                         "W"
3078 #else
3079                         "O"
3080 #endif
3081 #ifdef DEBUG
3082                         " DEBUG"
3083 #endif
3084 #ifdef MODULE
3085                         " MODULE"
3086 #endif
3087                         "].\n");
3088 
3089         ntfs_debug("Debug messages are enabled.");
3090 
3091         ntfs_index_ctx_cache = kmem_cache_create(ntfs_index_ctx_cache_name,
3092                         sizeof(ntfs_index_context), 0 /* offset */,
3093                         SLAB_HWCACHE_ALIGN, NULL /* ctor */);
3094         if (!ntfs_index_ctx_cache) {
3095                 pr_crit("Failed to create %s!\n", ntfs_index_ctx_cache_name);
3096                 goto ictx_err_out;
3097         }
3098         ntfs_attr_ctx_cache = kmem_cache_create(ntfs_attr_ctx_cache_name,
3099                         sizeof(ntfs_attr_search_ctx), 0 /* offset */,
3100                         SLAB_HWCACHE_ALIGN, NULL /* ctor */);
3101         if (!ntfs_attr_ctx_cache) {
3102                 pr_crit("NTFS: Failed to create %s!\n",
3103                         ntfs_attr_ctx_cache_name);
3104                 goto actx_err_out;
3105         }
3106 
3107         ntfs_name_cache = kmem_cache_create(ntfs_name_cache_name,
3108                         (NTFS_MAX_NAME_LEN+1) * sizeof(ntfschar), 0,
3109                         SLAB_HWCACHE_ALIGN, NULL);
3110         if (!ntfs_name_cache) {
3111                 pr_crit("Failed to create %s!\n", ntfs_name_cache_name);
3112                 goto name_err_out;
3113         }
3114 
3115         ntfs_inode_cache = kmem_cache_create(ntfs_inode_cache_name,
3116                         sizeof(ntfs_inode), 0,
3117                         SLAB_RECLAIM_ACCOUNT|SLAB_MEM_SPREAD, NULL);
3118         if (!ntfs_inode_cache) {
3119                 pr_crit("Failed to create %s!\n", ntfs_inode_cache_name);
3120                 goto inode_err_out;
3121         }
3122 
3123         ntfs_big_inode_cache = kmem_cache_create(ntfs_big_inode_cache_name,
3124                         sizeof(big_ntfs_inode), 0,
3125                         SLAB_HWCACHE_ALIGN|SLAB_RECLAIM_ACCOUNT|SLAB_MEM_SPREAD|
3126                         SLAB_ACCOUNT, ntfs_big_inode_init_once);
3127         if (!ntfs_big_inode_cache) {
3128                 pr_crit("Failed to create %s!\n", ntfs_big_inode_cache_name);
3129                 goto big_inode_err_out;
3130         }
3131 
3132         /* Register the ntfs sysctls. */
3133         err = ntfs_sysctl(1);
3134         if (err) {
3135                 pr_crit("Failed to register NTFS sysctls!\n");
3136                 goto sysctl_err_out;
3137         }
3138 
3139         err = register_filesystem(&ntfs_fs_type);
3140         if (!err) {
3141                 ntfs_debug("NTFS driver registered successfully.");
3142                 return 0; /* Success! */
3143         }
3144         pr_crit("Failed to register NTFS filesystem driver!\n");
3145 
3146         /* Unregister the ntfs sysctls. */
3147         ntfs_sysctl(0);
3148 sysctl_err_out:
3149         kmem_cache_destroy(ntfs_big_inode_cache);
3150 big_inode_err_out:
3151         kmem_cache_destroy(ntfs_inode_cache);
3152 inode_err_out:
3153         kmem_cache_destroy(ntfs_name_cache);
3154 name_err_out:
3155         kmem_cache_destroy(ntfs_attr_ctx_cache);
3156 actx_err_out:
3157         kmem_cache_destroy(ntfs_index_ctx_cache);
3158 ictx_err_out:
3159         if (!err) {
3160                 pr_crit("Aborting NTFS filesystem driver registration...\n");
3161                 err = -ENOMEM;
3162         }
3163         return err;
3164 }
3165 
3166 static void __exit exit_ntfs_fs(void)
3167 {
3168         ntfs_debug("Unregistering NTFS driver.");
3169 
3170         unregister_filesystem(&ntfs_fs_type);
3171 
3172         /*
3173          * Make sure all delayed rcu free inodes are flushed before we
3174          * destroy cache.
3175          */
3176         rcu_barrier();
3177         kmem_cache_destroy(ntfs_big_inode_cache);
3178         kmem_cache_destroy(ntfs_inode_cache);
3179         kmem_cache_destroy(ntfs_name_cache);
3180         kmem_cache_destroy(ntfs_attr_ctx_cache);
3181         kmem_cache_destroy(ntfs_index_ctx_cache);
3182         /* Unregister the ntfs sysctls. */
3183         ntfs_sysctl(0);
3184 }
3185 
3186 MODULE_AUTHOR("Anton Altaparmakov <anton@tuxera.com>");
3187 MODULE_DESCRIPTION("NTFS 1.2/3.x driver - Copyright (c) 2001-2014 Anton Altaparmakov and Tuxera Inc.");
3188 MODULE_VERSION(NTFS_VERSION);
3189 MODULE_LICENSE("GPL");
3190 #ifdef DEBUG
3191 module_param(debug_msgs, bint, 0);
3192 MODULE_PARM_DESC(debug_msgs, "Enable debug messages.");
3193 #endif
3194 
3195 module_init(init_ntfs_fs)
3196 module_exit(exit_ntfs_fs)