linux/fs/ntfs/super.c
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   1/*
   2 * super.c - NTFS kernel super block handling. Part of the Linux-NTFS project.
   3 *
   4 * Copyright (c) 2001-2012 Anton Altaparmakov and Tuxera Inc.
   5 * Copyright (c) 2001,2002 Richard Russon
   6 *
   7 * This program/include file is free software; you can redistribute it and/or
   8 * modify it under the terms of the GNU General Public License as published
   9 * by the Free Software Foundation; either version 2 of the License, or
  10 * (at your option) any later version.
  11 *
  12 * This program/include file is distributed in the hope that it will be
  13 * useful, but WITHOUT ANY WARRANTY; without even the implied warranty
  14 * of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15 * GNU General Public License for more details.
  16 *
  17 * You should have received a copy of the GNU General Public License
  18 * along with this program (in the main directory of the Linux-NTFS
  19 * distribution in the file COPYING); if not, write to the Free Software
  20 * Foundation,Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
  21 */
  22
  23#include <linux/stddef.h>
  24#include <linux/init.h>
  25#include <linux/slab.h>
  26#include <linux/string.h>
  27#include <linux/spinlock.h>
  28#include <linux/blkdev.h>       /* For bdev_logical_block_size(). */
  29#include <linux/backing-dev.h>
  30#include <linux/buffer_head.h>
  31#include <linux/vfs.h>
  32#include <linux/moduleparam.h>
  33#include <linux/bitmap.h>
  34
  35#include "sysctl.h"
  36#include "logfile.h"
  37#include "quota.h"
  38#include "usnjrnl.h"
  39#include "dir.h"
  40#include "debug.h"
  41#include "index.h"
  42#include "inode.h"
  43#include "aops.h"
  44#include "layout.h"
  45#include "malloc.h"
  46#include "ntfs.h"
  47
  48/* Number of mounted filesystems which have compression enabled. */
  49static unsigned long ntfs_nr_compression_users;
  50
  51/* A global default upcase table and a corresponding reference count. */
  52static ntfschar *default_upcase = NULL;
  53static unsigned long ntfs_nr_upcase_users = 0;
  54
  55/* Error constants/strings used in inode.c::ntfs_show_options(). */
  56typedef enum {
  57        /* One of these must be present, default is ON_ERRORS_CONTINUE. */
  58        ON_ERRORS_PANIC                 = 0x01,
  59        ON_ERRORS_REMOUNT_RO            = 0x02,
  60        ON_ERRORS_CONTINUE              = 0x04,
  61        /* Optional, can be combined with any of the above. */
  62        ON_ERRORS_RECOVER               = 0x10,
  63} ON_ERRORS_ACTIONS;
  64
  65const option_t on_errors_arr[] = {
  66        { ON_ERRORS_PANIC,      "panic" },
  67        { ON_ERRORS_REMOUNT_RO, "remount-ro", },
  68        { ON_ERRORS_CONTINUE,   "continue", },
  69        { ON_ERRORS_RECOVER,    "recover" },
  70        { 0,                    NULL }
  71};
  72
  73/**
  74 * simple_getbool -
  75 *
  76 * Copied from old ntfs driver (which copied from vfat driver).
  77 */
  78static int simple_getbool(char *s, bool *setval)
  79{
  80        if (s) {
  81                if (!strcmp(s, "1") || !strcmp(s, "yes") || !strcmp(s, "true"))
  82                        *setval = true;
  83                else if (!strcmp(s, "0") || !strcmp(s, "no") ||
  84                                                        !strcmp(s, "false"))
  85                        *setval = false;
  86                else
  87                        return 0;
  88        } else
  89                *setval = true;
  90        return 1;
  91}
  92
  93/**
  94 * parse_options - parse the (re)mount options
  95 * @vol:        ntfs volume
  96 * @opt:        string containing the (re)mount options
  97 *
  98 * Parse the recognized options in @opt for the ntfs volume described by @vol.
  99 */
 100static bool parse_options(ntfs_volume *vol, char *opt)
 101{
 102        char *p, *v, *ov;
 103        static char *utf8 = "utf8";
 104        int errors = 0, sloppy = 0;
 105        kuid_t uid = INVALID_UID;
 106        kgid_t gid = INVALID_GID;
 107        umode_t fmask = (umode_t)-1, dmask = (umode_t)-1;
 108        int mft_zone_multiplier = -1, on_errors = -1;
 109        int show_sys_files = -1, case_sensitive = -1, disable_sparse = -1;
 110        struct nls_table *nls_map = NULL, *old_nls;
 111
 112        /* I am lazy... (-8 */
 113#define NTFS_GETOPT_WITH_DEFAULT(option, variable, default_value)       \
 114        if (!strcmp(p, option)) {                                       \
 115                if (!v || !*v)                                          \
 116                        variable = default_value;                       \
 117                else {                                                  \
 118                        variable = simple_strtoul(ov = v, &v, 0);       \
 119                        if (*v)                                         \
 120                                goto needs_val;                         \
 121                }                                                       \
 122        }
 123#define NTFS_GETOPT(option, variable)                                   \
 124        if (!strcmp(p, option)) {                                       \
 125                if (!v || !*v)                                          \
 126                        goto needs_arg;                                 \
 127                variable = simple_strtoul(ov = v, &v, 0);               \
 128                if (*v)                                                 \
 129                        goto needs_val;                                 \
 130        }
 131#define NTFS_GETOPT_UID(option, variable)                               \
 132        if (!strcmp(p, option)) {                                       \
 133                uid_t uid_value;                                        \
 134                if (!v || !*v)                                          \
 135                        goto needs_arg;                                 \
 136                uid_value = simple_strtoul(ov = v, &v, 0);              \
 137                if (*v)                                                 \
 138                        goto needs_val;                                 \
 139                variable = make_kuid(current_user_ns(), uid_value);     \
 140                if (!uid_valid(variable))                               \
 141                        goto needs_val;                                 \
 142        }
 143#define NTFS_GETOPT_GID(option, variable)                               \
 144        if (!strcmp(p, option)) {                                       \
 145                gid_t gid_value;                                        \
 146                if (!v || !*v)                                          \
 147                        goto needs_arg;                                 \
 148                gid_value = simple_strtoul(ov = v, &v, 0);              \
 149                if (*v)                                                 \
 150                        goto needs_val;                                 \
 151                variable = make_kgid(current_user_ns(), gid_value);     \
 152                if (!gid_valid(variable))                               \
 153                        goto needs_val;                                 \
 154        }
 155#define NTFS_GETOPT_OCTAL(option, variable)                             \
 156        if (!strcmp(p, option)) {                                       \
 157                if (!v || !*v)                                          \
 158                        goto needs_arg;                                 \
 159                variable = simple_strtoul(ov = v, &v, 8);               \
 160                if (*v)                                                 \
 161                        goto needs_val;                                 \
 162        }
 163#define NTFS_GETOPT_BOOL(option, variable)                              \
 164        if (!strcmp(p, option)) {                                       \
 165                bool val;                                               \
 166                if (!simple_getbool(v, &val))                           \
 167                        goto needs_bool;                                \
 168                variable = val;                                         \
 169        }
 170#define NTFS_GETOPT_OPTIONS_ARRAY(option, variable, opt_array)          \
 171        if (!strcmp(p, option)) {                                       \
 172                int _i;                                                 \
 173                if (!v || !*v)                                          \
 174                        goto needs_arg;                                 \
 175                ov = v;                                                 \
 176                if (variable == -1)                                     \
 177                        variable = 0;                                   \
 178                for (_i = 0; opt_array[_i].str && *opt_array[_i].str; _i++) \
 179                        if (!strcmp(opt_array[_i].str, v)) {            \
 180                                variable |= opt_array[_i].val;          \
 181                                break;                                  \
 182                        }                                               \
 183                if (!opt_array[_i].str || !*opt_array[_i].str)          \
 184                        goto needs_val;                                 \
 185        }
 186        if (!opt || !*opt)
 187                goto no_mount_options;
 188        ntfs_debug("Entering with mount options string: %s", opt);
 189        while ((p = strsep(&opt, ","))) {
 190                if ((v = strchr(p, '=')))
 191                        *v++ = 0;
 192                NTFS_GETOPT_UID("uid", uid)
 193                else NTFS_GETOPT_GID("gid", gid)
 194                else NTFS_GETOPT_OCTAL("umask", fmask = dmask)
 195                else NTFS_GETOPT_OCTAL("fmask", fmask)
 196                else NTFS_GETOPT_OCTAL("dmask", dmask)
 197                else NTFS_GETOPT("mft_zone_multiplier", mft_zone_multiplier)
 198                else NTFS_GETOPT_WITH_DEFAULT("sloppy", sloppy, true)
 199                else NTFS_GETOPT_BOOL("show_sys_files", show_sys_files)
 200                else NTFS_GETOPT_BOOL("case_sensitive", case_sensitive)
 201                else NTFS_GETOPT_BOOL("disable_sparse", disable_sparse)
 202                else NTFS_GETOPT_OPTIONS_ARRAY("errors", on_errors,
 203                                on_errors_arr)
 204                else if (!strcmp(p, "posix") || !strcmp(p, "show_inodes"))
 205                        ntfs_warning(vol->sb, "Ignoring obsolete option %s.",
 206                                        p);
 207                else if (!strcmp(p, "nls") || !strcmp(p, "iocharset")) {
 208                        if (!strcmp(p, "iocharset"))
 209                                ntfs_warning(vol->sb, "Option iocharset is "
 210                                                "deprecated. Please use "
 211                                                "option nls=<charsetname> in "
 212                                                "the future.");
 213                        if (!v || !*v)
 214                                goto needs_arg;
 215use_utf8:
 216                        old_nls = nls_map;
 217                        nls_map = load_nls(v);
 218                        if (!nls_map) {
 219                                if (!old_nls) {
 220                                        ntfs_error(vol->sb, "NLS character set "
 221                                                        "%s not found.", v);
 222                                        return false;
 223                                }
 224                                ntfs_error(vol->sb, "NLS character set %s not "
 225                                                "found. Using previous one %s.",
 226                                                v, old_nls->charset);
 227                                nls_map = old_nls;
 228                        } else /* nls_map */ {
 229                                unload_nls(old_nls);
 230                        }
 231                } else if (!strcmp(p, "utf8")) {
 232                        bool val = false;
 233                        ntfs_warning(vol->sb, "Option utf8 is no longer "
 234                                   "supported, using option nls=utf8. Please "
 235                                   "use option nls=utf8 in the future and "
 236                                   "make sure utf8 is compiled either as a "
 237                                   "module or into the kernel.");
 238                        if (!v || !*v)
 239                                val = true;
 240                        else if (!simple_getbool(v, &val))
 241                                goto needs_bool;
 242                        if (val) {
 243                                v = utf8;
 244                                goto use_utf8;
 245                        }
 246                } else {
 247                        ntfs_error(vol->sb, "Unrecognized mount option %s.", p);
 248                        if (errors < INT_MAX)
 249                                errors++;
 250                }
 251#undef NTFS_GETOPT_OPTIONS_ARRAY
 252#undef NTFS_GETOPT_BOOL
 253#undef NTFS_GETOPT
 254#undef NTFS_GETOPT_WITH_DEFAULT
 255        }
 256no_mount_options:
 257        if (errors && !sloppy)
 258                return false;
 259        if (sloppy)
 260                ntfs_warning(vol->sb, "Sloppy option given. Ignoring "
 261                                "unrecognized mount option(s) and continuing.");
 262        /* Keep this first! */
 263        if (on_errors != -1) {
 264                if (!on_errors) {
 265                        ntfs_error(vol->sb, "Invalid errors option argument "
 266                                        "or bug in options parser.");
 267                        return false;
 268                }
 269        }
 270        if (nls_map) {
 271                if (vol->nls_map && vol->nls_map != nls_map) {
 272                        ntfs_error(vol->sb, "Cannot change NLS character set "
 273                                        "on remount.");
 274                        return false;
 275                } /* else (!vol->nls_map) */
 276                ntfs_debug("Using NLS character set %s.", nls_map->charset);
 277                vol->nls_map = nls_map;
 278        } else /* (!nls_map) */ {
 279                if (!vol->nls_map) {
 280                        vol->nls_map = load_nls_default();
 281                        if (!vol->nls_map) {
 282                                ntfs_error(vol->sb, "Failed to load default "
 283                                                "NLS character set.");
 284                                return false;
 285                        }
 286                        ntfs_debug("Using default NLS character set (%s).",
 287                                        vol->nls_map->charset);
 288                }
 289        }
 290        if (mft_zone_multiplier != -1) {
 291                if (vol->mft_zone_multiplier && vol->mft_zone_multiplier !=
 292                                mft_zone_multiplier) {
 293                        ntfs_error(vol->sb, "Cannot change mft_zone_multiplier "
 294                                        "on remount.");
 295                        return false;
 296                }
 297                if (mft_zone_multiplier < 1 || mft_zone_multiplier > 4) {
 298                        ntfs_error(vol->sb, "Invalid mft_zone_multiplier. "
 299                                        "Using default value, i.e. 1.");
 300                        mft_zone_multiplier = 1;
 301                }
 302                vol->mft_zone_multiplier = mft_zone_multiplier;
 303        }
 304        if (!vol->mft_zone_multiplier)
 305                vol->mft_zone_multiplier = 1;
 306        if (on_errors != -1)
 307                vol->on_errors = on_errors;
 308        if (!vol->on_errors || vol->on_errors == ON_ERRORS_RECOVER)
 309                vol->on_errors |= ON_ERRORS_CONTINUE;
 310        if (uid_valid(uid))
 311                vol->uid = uid;
 312        if (gid_valid(gid))
 313                vol->gid = gid;
 314        if (fmask != (umode_t)-1)
 315                vol->fmask = fmask;
 316        if (dmask != (umode_t)-1)
 317                vol->dmask = dmask;
 318        if (show_sys_files != -1) {
 319                if (show_sys_files)
 320                        NVolSetShowSystemFiles(vol);
 321                else
 322                        NVolClearShowSystemFiles(vol);
 323        }
 324        if (case_sensitive != -1) {
 325                if (case_sensitive)
 326                        NVolSetCaseSensitive(vol);
 327                else
 328                        NVolClearCaseSensitive(vol);
 329        }
 330        if (disable_sparse != -1) {
 331                if (disable_sparse)
 332                        NVolClearSparseEnabled(vol);
 333                else {
 334                        if (!NVolSparseEnabled(vol) &&
 335                                        vol->major_ver && vol->major_ver < 3)
 336                                ntfs_warning(vol->sb, "Not enabling sparse "
 337                                                "support due to NTFS volume "
 338                                                "version %i.%i (need at least "
 339                                                "version 3.0).", vol->major_ver,
 340                                                vol->minor_ver);
 341                        else
 342                                NVolSetSparseEnabled(vol);
 343                }
 344        }
 345        return true;
 346needs_arg:
 347        ntfs_error(vol->sb, "The %s option requires an argument.", p);
 348        return false;
 349needs_bool:
 350        ntfs_error(vol->sb, "The %s option requires a boolean argument.", p);
 351        return false;
 352needs_val:
 353        ntfs_error(vol->sb, "Invalid %s option argument: %s", p, ov);
 354        return false;
 355}
 356
 357#ifdef NTFS_RW
 358
 359/**
 360 * ntfs_write_volume_flags - write new flags to the volume information flags
 361 * @vol:        ntfs volume on which to modify the flags
 362 * @flags:      new flags value for the volume information flags
 363 *
 364 * Internal function.  You probably want to use ntfs_{set,clear}_volume_flags()
 365 * instead (see below).
 366 *
 367 * Replace the volume information flags on the volume @vol with the value
 368 * supplied in @flags.  Note, this overwrites the volume information flags, so
 369 * make sure to combine the flags you want to modify with the old flags and use
 370 * the result when calling ntfs_write_volume_flags().
 371 *
 372 * Return 0 on success and -errno on error.
 373 */
 374static int ntfs_write_volume_flags(ntfs_volume *vol, const VOLUME_FLAGS flags)
 375{
 376        ntfs_inode *ni = NTFS_I(vol->vol_ino);
 377        MFT_RECORD *m;
 378        VOLUME_INFORMATION *vi;
 379        ntfs_attr_search_ctx *ctx;
 380        int err;
 381
 382        ntfs_debug("Entering, old flags = 0x%x, new flags = 0x%x.",
 383                        le16_to_cpu(vol->vol_flags), le16_to_cpu(flags));
 384        if (vol->vol_flags == flags)
 385                goto done;
 386        BUG_ON(!ni);
 387        m = map_mft_record(ni);
 388        if (IS_ERR(m)) {
 389                err = PTR_ERR(m);
 390                goto err_out;
 391        }
 392        ctx = ntfs_attr_get_search_ctx(ni, m);
 393        if (!ctx) {
 394                err = -ENOMEM;
 395                goto put_unm_err_out;
 396        }
 397        err = ntfs_attr_lookup(AT_VOLUME_INFORMATION, NULL, 0, 0, 0, NULL, 0,
 398                        ctx);
 399        if (err)
 400                goto put_unm_err_out;
 401        vi = (VOLUME_INFORMATION*)((u8*)ctx->attr +
 402                        le16_to_cpu(ctx->attr->data.resident.value_offset));
 403        vol->vol_flags = vi->flags = flags;
 404        flush_dcache_mft_record_page(ctx->ntfs_ino);
 405        mark_mft_record_dirty(ctx->ntfs_ino);
 406        ntfs_attr_put_search_ctx(ctx);
 407        unmap_mft_record(ni);
 408done:
 409        ntfs_debug("Done.");
 410        return 0;
 411put_unm_err_out:
 412        if (ctx)
 413                ntfs_attr_put_search_ctx(ctx);
 414        unmap_mft_record(ni);
 415err_out:
 416        ntfs_error(vol->sb, "Failed with error code %i.", -err);
 417        return err;
 418}
 419
 420/**
 421 * ntfs_set_volume_flags - set bits in the volume information flags
 422 * @vol:        ntfs volume on which to modify the flags
 423 * @flags:      flags to set on the volume
 424 *
 425 * Set the bits in @flags in the volume information flags on the volume @vol.
 426 *
 427 * Return 0 on success and -errno on error.
 428 */
 429static inline int ntfs_set_volume_flags(ntfs_volume *vol, VOLUME_FLAGS flags)
 430{
 431        flags &= VOLUME_FLAGS_MASK;
 432        return ntfs_write_volume_flags(vol, vol->vol_flags | flags);
 433}
 434
 435/**
 436 * ntfs_clear_volume_flags - clear bits in the volume information flags
 437 * @vol:        ntfs volume on which to modify the flags
 438 * @flags:      flags to clear on the volume
 439 *
 440 * Clear the bits in @flags in the volume information flags on the volume @vol.
 441 *
 442 * Return 0 on success and -errno on error.
 443 */
 444static inline int ntfs_clear_volume_flags(ntfs_volume *vol, VOLUME_FLAGS flags)
 445{
 446        flags &= VOLUME_FLAGS_MASK;
 447        flags = vol->vol_flags & cpu_to_le16(~le16_to_cpu(flags));
 448        return ntfs_write_volume_flags(vol, flags);
 449}
 450
 451#endif /* NTFS_RW */
 452
 453/**
 454 * ntfs_remount - change the mount options of a mounted ntfs filesystem
 455 * @sb:         superblock of mounted ntfs filesystem
 456 * @flags:      remount flags
 457 * @opt:        remount options string
 458 *
 459 * Change the mount options of an already mounted ntfs filesystem.
 460 *
 461 * NOTE:  The VFS sets the @sb->s_flags remount flags to @flags after
 462 * ntfs_remount() returns successfully (i.e. returns 0).  Otherwise,
 463 * @sb->s_flags are not changed.
 464 */
 465static int ntfs_remount(struct super_block *sb, int *flags, char *opt)
 466{
 467        ntfs_volume *vol = NTFS_SB(sb);
 468
 469        ntfs_debug("Entering with remount options string: %s", opt);
 470
 471#ifndef NTFS_RW
 472        /* For read-only compiled driver, enforce read-only flag. */
 473        *flags |= MS_RDONLY;
 474#else /* NTFS_RW */
 475        /*
 476         * For the read-write compiled driver, if we are remounting read-write,
 477         * make sure there are no volume errors and that no unsupported volume
 478         * flags are set.  Also, empty the logfile journal as it would become
 479         * stale as soon as something is written to the volume and mark the
 480         * volume dirty so that chkdsk is run if the volume is not umounted
 481         * cleanly.  Finally, mark the quotas out of date so Windows rescans
 482         * the volume on boot and updates them.
 483         *
 484         * When remounting read-only, mark the volume clean if no volume errors
 485         * have occurred.
 486         */
 487        if ((sb->s_flags & MS_RDONLY) && !(*flags & MS_RDONLY)) {
 488                static const char *es = ".  Cannot remount read-write.";
 489
 490                /* Remounting read-write. */
 491                if (NVolErrors(vol)) {
 492                        ntfs_error(sb, "Volume has errors and is read-only%s",
 493                                        es);
 494                        return -EROFS;
 495                }
 496                if (vol->vol_flags & VOLUME_IS_DIRTY) {
 497                        ntfs_error(sb, "Volume is dirty and read-only%s", es);
 498                        return -EROFS;
 499                }
 500                if (vol->vol_flags & VOLUME_MODIFIED_BY_CHKDSK) {
 501                        ntfs_error(sb, "Volume has been modified by chkdsk "
 502                                        "and is read-only%s", es);
 503                        return -EROFS;
 504                }
 505                if (vol->vol_flags & VOLUME_MUST_MOUNT_RO_MASK) {
 506                        ntfs_error(sb, "Volume has unsupported flags set "
 507                                        "(0x%x) and is read-only%s",
 508                                        (unsigned)le16_to_cpu(vol->vol_flags),
 509                                        es);
 510                        return -EROFS;
 511                }
 512                if (ntfs_set_volume_flags(vol, VOLUME_IS_DIRTY)) {
 513                        ntfs_error(sb, "Failed to set dirty bit in volume "
 514                                        "information flags%s", es);
 515                        return -EROFS;
 516                }
 517#if 0
 518                // TODO: Enable this code once we start modifying anything that
 519                //       is different between NTFS 1.2 and 3.x...
 520                /* Set NT4 compatibility flag on newer NTFS version volumes. */
 521                if ((vol->major_ver > 1)) {
 522                        if (ntfs_set_volume_flags(vol, VOLUME_MOUNTED_ON_NT4)) {
 523                                ntfs_error(sb, "Failed to set NT4 "
 524                                                "compatibility flag%s", es);
 525                                NVolSetErrors(vol);
 526                                return -EROFS;
 527                        }
 528                }
 529#endif
 530                if (!ntfs_empty_logfile(vol->logfile_ino)) {
 531                        ntfs_error(sb, "Failed to empty journal $LogFile%s",
 532                                        es);
 533                        NVolSetErrors(vol);
 534                        return -EROFS;
 535                }
 536                if (!ntfs_mark_quotas_out_of_date(vol)) {
 537                        ntfs_error(sb, "Failed to mark quotas out of date%s",
 538                                        es);
 539                        NVolSetErrors(vol);
 540                        return -EROFS;
 541                }
 542                if (!ntfs_stamp_usnjrnl(vol)) {
 543                        ntfs_error(sb, "Failed to stamp transation log "
 544                                        "($UsnJrnl)%s", es);
 545                        NVolSetErrors(vol);
 546                        return -EROFS;
 547                }
 548        } else if (!(sb->s_flags & MS_RDONLY) && (*flags & MS_RDONLY)) {
 549                /* Remounting read-only. */
 550                if (!NVolErrors(vol)) {
 551                        if (ntfs_clear_volume_flags(vol, VOLUME_IS_DIRTY))
 552                                ntfs_warning(sb, "Failed to clear dirty bit "
 553                                                "in volume information "
 554                                                "flags.  Run chkdsk.");
 555                }
 556        }
 557#endif /* NTFS_RW */
 558
 559        // TODO: Deal with *flags.
 560
 561        if (!parse_options(vol, opt))
 562                return -EINVAL;
 563
 564        ntfs_debug("Done.");
 565        return 0;
 566}
 567
 568/**
 569 * is_boot_sector_ntfs - check whether a boot sector is a valid NTFS boot sector
 570 * @sb:         Super block of the device to which @b belongs.
 571 * @b:          Boot sector of device @sb to check.
 572 * @silent:     If 'true', all output will be silenced.
 573 *
 574 * is_boot_sector_ntfs() checks whether the boot sector @b is a valid NTFS boot
 575 * sector. Returns 'true' if it is valid and 'false' if not.
 576 *
 577 * @sb is only needed for warning/error output, i.e. it can be NULL when silent
 578 * is 'true'.
 579 */
 580static bool is_boot_sector_ntfs(const struct super_block *sb,
 581                const NTFS_BOOT_SECTOR *b, const bool silent)
 582{
 583        /*
 584         * Check that checksum == sum of u32 values from b to the checksum
 585         * field.  If checksum is zero, no checking is done.  We will work when
 586         * the checksum test fails, since some utilities update the boot sector
 587         * ignoring the checksum which leaves the checksum out-of-date.  We
 588         * report a warning if this is the case.
 589         */
 590        if ((void*)b < (void*)&b->checksum && b->checksum && !silent) {
 591                le32 *u;
 592                u32 i;
 593
 594                for (i = 0, u = (le32*)b; u < (le32*)(&b->checksum); ++u)
 595                        i += le32_to_cpup(u);
 596                if (le32_to_cpu(b->checksum) != i)
 597                        ntfs_warning(sb, "Invalid boot sector checksum.");
 598        }
 599        /* Check OEMidentifier is "NTFS    " */
 600        if (b->oem_id != magicNTFS)
 601                goto not_ntfs;
 602        /* Check bytes per sector value is between 256 and 4096. */
 603        if (le16_to_cpu(b->bpb.bytes_per_sector) < 0x100 ||
 604                        le16_to_cpu(b->bpb.bytes_per_sector) > 0x1000)
 605                goto not_ntfs;
 606        /* Check sectors per cluster value is valid. */
 607        switch (b->bpb.sectors_per_cluster) {
 608        case 1: case 2: case 4: case 8: case 16: case 32: case 64: case 128:
 609                break;
 610        default:
 611                goto not_ntfs;
 612        }
 613        /* Check the cluster size is not above the maximum (64kiB). */
 614        if ((u32)le16_to_cpu(b->bpb.bytes_per_sector) *
 615                        b->bpb.sectors_per_cluster > NTFS_MAX_CLUSTER_SIZE)
 616                goto not_ntfs;
 617        /* Check reserved/unused fields are really zero. */
 618        if (le16_to_cpu(b->bpb.reserved_sectors) ||
 619                        le16_to_cpu(b->bpb.root_entries) ||
 620                        le16_to_cpu(b->bpb.sectors) ||
 621                        le16_to_cpu(b->bpb.sectors_per_fat) ||
 622                        le32_to_cpu(b->bpb.large_sectors) || b->bpb.fats)
 623                goto not_ntfs;
 624        /* Check clusters per file mft record value is valid. */
 625        if ((u8)b->clusters_per_mft_record < 0xe1 ||
 626                        (u8)b->clusters_per_mft_record > 0xf7)
 627                switch (b->clusters_per_mft_record) {
 628                case 1: case 2: case 4: case 8: case 16: case 32: case 64:
 629                        break;
 630                default:
 631                        goto not_ntfs;
 632                }
 633        /* Check clusters per index block value is valid. */
 634        if ((u8)b->clusters_per_index_record < 0xe1 ||
 635                        (u8)b->clusters_per_index_record > 0xf7)
 636                switch (b->clusters_per_index_record) {
 637                case 1: case 2: case 4: case 8: case 16: case 32: case 64:
 638                        break;
 639                default:
 640                        goto not_ntfs;
 641                }
 642        /*
 643         * Check for valid end of sector marker. We will work without it, but
 644         * many BIOSes will refuse to boot from a bootsector if the magic is
 645         * incorrect, so we emit a warning.
 646         */
 647        if (!silent && b->end_of_sector_marker != cpu_to_le16(0xaa55))
 648                ntfs_warning(sb, "Invalid end of sector marker.");
 649        return true;
 650not_ntfs:
 651        return false;
 652}
 653
 654/**
 655 * read_ntfs_boot_sector - read the NTFS boot sector of a device
 656 * @sb:         super block of device to read the boot sector from
 657 * @silent:     if true, suppress all output
 658 *
 659 * Reads the boot sector from the device and validates it. If that fails, tries
 660 * to read the backup boot sector, first from the end of the device a-la NT4 and
 661 * later and then from the middle of the device a-la NT3.51 and before.
 662 *
 663 * If a valid boot sector is found but it is not the primary boot sector, we
 664 * repair the primary boot sector silently (unless the device is read-only or
 665 * the primary boot sector is not accessible).
 666 *
 667 * NOTE: To call this function, @sb must have the fields s_dev, the ntfs super
 668 * block (u.ntfs_sb), nr_blocks and the device flags (s_flags) initialized
 669 * to their respective values.
 670 *
 671 * Return the unlocked buffer head containing the boot sector or NULL on error.
 672 */
 673static struct buffer_head *read_ntfs_boot_sector(struct super_block *sb,
 674                const int silent)
 675{
 676        const char *read_err_str = "Unable to read %s boot sector.";
 677        struct buffer_head *bh_primary, *bh_backup;
 678        sector_t nr_blocks = NTFS_SB(sb)->nr_blocks;
 679
 680        /* Try to read primary boot sector. */
 681        if ((bh_primary = sb_bread(sb, 0))) {
 682                if (is_boot_sector_ntfs(sb, (NTFS_BOOT_SECTOR*)
 683                                bh_primary->b_data, silent))
 684                        return bh_primary;
 685                if (!silent)
 686                        ntfs_error(sb, "Primary boot sector is invalid.");
 687        } else if (!silent)
 688                ntfs_error(sb, read_err_str, "primary");
 689        if (!(NTFS_SB(sb)->on_errors & ON_ERRORS_RECOVER)) {
 690                if (bh_primary)
 691                        brelse(bh_primary);
 692                if (!silent)
 693                        ntfs_error(sb, "Mount option errors=recover not used. "
 694                                        "Aborting without trying to recover.");
 695                return NULL;
 696        }
 697        /* Try to read NT4+ backup boot sector. */
 698        if ((bh_backup = sb_bread(sb, nr_blocks - 1))) {
 699                if (is_boot_sector_ntfs(sb, (NTFS_BOOT_SECTOR*)
 700                                bh_backup->b_data, silent))
 701                        goto hotfix_primary_boot_sector;
 702                brelse(bh_backup);
 703        } else if (!silent)
 704                ntfs_error(sb, read_err_str, "backup");
 705        /* Try to read NT3.51- backup boot sector. */
 706        if ((bh_backup = sb_bread(sb, nr_blocks >> 1))) {
 707                if (is_boot_sector_ntfs(sb, (NTFS_BOOT_SECTOR*)
 708                                bh_backup->b_data, silent))
 709                        goto hotfix_primary_boot_sector;
 710                if (!silent)
 711                        ntfs_error(sb, "Could not find a valid backup boot "
 712                                        "sector.");
 713                brelse(bh_backup);
 714        } else if (!silent)
 715                ntfs_error(sb, read_err_str, "backup");
 716        /* We failed. Cleanup and return. */
 717        if (bh_primary)
 718                brelse(bh_primary);
 719        return NULL;
 720hotfix_primary_boot_sector:
 721        if (bh_primary) {
 722                /*
 723                 * If we managed to read sector zero and the volume is not
 724                 * read-only, copy the found, valid backup boot sector to the
 725                 * primary boot sector.  Note we only copy the actual boot
 726                 * sector structure, not the actual whole device sector as that
 727                 * may be bigger and would potentially damage the $Boot system
 728                 * file (FIXME: Would be nice to know if the backup boot sector
 729                 * on a large sector device contains the whole boot loader or
 730                 * just the first 512 bytes).
 731                 */
 732                if (!(sb->s_flags & MS_RDONLY)) {
 733                        ntfs_warning(sb, "Hot-fix: Recovering invalid primary "
 734                                        "boot sector from backup copy.");
 735                        memcpy(bh_primary->b_data, bh_backup->b_data,
 736                                        NTFS_BLOCK_SIZE);
 737                        mark_buffer_dirty(bh_primary);
 738                        sync_dirty_buffer(bh_primary);
 739                        if (buffer_uptodate(bh_primary)) {
 740                                brelse(bh_backup);
 741                                return bh_primary;
 742                        }
 743                        ntfs_error(sb, "Hot-fix: Device write error while "
 744                                        "recovering primary boot sector.");
 745                } else {
 746                        ntfs_warning(sb, "Hot-fix: Recovery of primary boot "
 747                                        "sector failed: Read-only mount.");
 748                }
 749                brelse(bh_primary);
 750        }
 751        ntfs_warning(sb, "Using backup boot sector.");
 752        return bh_backup;
 753}
 754
 755/**
 756 * parse_ntfs_boot_sector - parse the boot sector and store the data in @vol
 757 * @vol:        volume structure to initialise with data from boot sector
 758 * @b:          boot sector to parse
 759 *
 760 * Parse the ntfs boot sector @b and store all imporant information therein in
 761 * the ntfs super block @vol.  Return 'true' on success and 'false' on error.
 762 */
 763static bool parse_ntfs_boot_sector(ntfs_volume *vol, const NTFS_BOOT_SECTOR *b)
 764{
 765        unsigned int sectors_per_cluster_bits, nr_hidden_sects;
 766        int clusters_per_mft_record, clusters_per_index_record;
 767        s64 ll;
 768
 769        vol->sector_size = le16_to_cpu(b->bpb.bytes_per_sector);
 770        vol->sector_size_bits = ffs(vol->sector_size) - 1;
 771        ntfs_debug("vol->sector_size = %i (0x%x)", vol->sector_size,
 772                        vol->sector_size);
 773        ntfs_debug("vol->sector_size_bits = %i (0x%x)", vol->sector_size_bits,
 774                        vol->sector_size_bits);
 775        if (vol->sector_size < vol->sb->s_blocksize) {
 776                ntfs_error(vol->sb, "Sector size (%i) is smaller than the "
 777                                "device block size (%lu).  This is not "
 778                                "supported.  Sorry.", vol->sector_size,
 779                                vol->sb->s_blocksize);
 780                return false;
 781        }
 782        ntfs_debug("sectors_per_cluster = 0x%x", b->bpb.sectors_per_cluster);
 783        sectors_per_cluster_bits = ffs(b->bpb.sectors_per_cluster) - 1;
 784        ntfs_debug("sectors_per_cluster_bits = 0x%x",
 785                        sectors_per_cluster_bits);
 786        nr_hidden_sects = le32_to_cpu(b->bpb.hidden_sectors);
 787        ntfs_debug("number of hidden sectors = 0x%x", nr_hidden_sects);
 788        vol->cluster_size = vol->sector_size << sectors_per_cluster_bits;
 789        vol->cluster_size_mask = vol->cluster_size - 1;
 790        vol->cluster_size_bits = ffs(vol->cluster_size) - 1;
 791        ntfs_debug("vol->cluster_size = %i (0x%x)", vol->cluster_size,
 792                        vol->cluster_size);
 793        ntfs_debug("vol->cluster_size_mask = 0x%x", vol->cluster_size_mask);
 794        ntfs_debug("vol->cluster_size_bits = %i", vol->cluster_size_bits);
 795        if (vol->cluster_size < vol->sector_size) {
 796                ntfs_error(vol->sb, "Cluster size (%i) is smaller than the "
 797                                "sector size (%i).  This is not supported.  "
 798                                "Sorry.", vol->cluster_size, vol->sector_size);
 799                return false;
 800        }
 801        clusters_per_mft_record = b->clusters_per_mft_record;
 802        ntfs_debug("clusters_per_mft_record = %i (0x%x)",
 803                        clusters_per_mft_record, clusters_per_mft_record);
 804        if (clusters_per_mft_record > 0)
 805                vol->mft_record_size = vol->cluster_size <<
 806                                (ffs(clusters_per_mft_record) - 1);
 807        else
 808                /*
 809                 * When mft_record_size < cluster_size, clusters_per_mft_record
 810                 * = -log2(mft_record_size) bytes. mft_record_size normaly is
 811                 * 1024 bytes, which is encoded as 0xF6 (-10 in decimal).
 812                 */
 813                vol->mft_record_size = 1 << -clusters_per_mft_record;
 814        vol->mft_record_size_mask = vol->mft_record_size - 1;
 815        vol->mft_record_size_bits = ffs(vol->mft_record_size) - 1;
 816        ntfs_debug("vol->mft_record_size = %i (0x%x)", vol->mft_record_size,
 817                        vol->mft_record_size);
 818        ntfs_debug("vol->mft_record_size_mask = 0x%x",
 819                        vol->mft_record_size_mask);
 820        ntfs_debug("vol->mft_record_size_bits = %i (0x%x)",
 821                        vol->mft_record_size_bits, vol->mft_record_size_bits);
 822        /*
 823         * We cannot support mft record sizes above the PAGE_CACHE_SIZE since
 824         * we store $MFT/$DATA, the table of mft records in the page cache.
 825         */
 826        if (vol->mft_record_size > PAGE_CACHE_SIZE) {
 827                ntfs_error(vol->sb, "Mft record size (%i) exceeds the "
 828                                "PAGE_CACHE_SIZE on your system (%lu).  "
 829                                "This is not supported.  Sorry.",
 830                                vol->mft_record_size, PAGE_CACHE_SIZE);
 831                return false;
 832        }
 833        /* We cannot support mft record sizes below the sector size. */
 834        if (vol->mft_record_size < vol->sector_size) {
 835                ntfs_error(vol->sb, "Mft record size (%i) is smaller than the "
 836                                "sector size (%i).  This is not supported.  "
 837                                "Sorry.", vol->mft_record_size,
 838                                vol->sector_size);
 839                return false;
 840        }
 841        clusters_per_index_record = b->clusters_per_index_record;
 842        ntfs_debug("clusters_per_index_record = %i (0x%x)",
 843                        clusters_per_index_record, clusters_per_index_record);
 844        if (clusters_per_index_record > 0)
 845                vol->index_record_size = vol->cluster_size <<
 846                                (ffs(clusters_per_index_record) - 1);
 847        else
 848                /*
 849                 * When index_record_size < cluster_size,
 850                 * clusters_per_index_record = -log2(index_record_size) bytes.
 851                 * index_record_size normaly equals 4096 bytes, which is
 852                 * encoded as 0xF4 (-12 in decimal).
 853                 */
 854                vol->index_record_size = 1 << -clusters_per_index_record;
 855        vol->index_record_size_mask = vol->index_record_size - 1;
 856        vol->index_record_size_bits = ffs(vol->index_record_size) - 1;
 857        ntfs_debug("vol->index_record_size = %i (0x%x)",
 858                        vol->index_record_size, vol->index_record_size);
 859        ntfs_debug("vol->index_record_size_mask = 0x%x",
 860                        vol->index_record_size_mask);
 861        ntfs_debug("vol->index_record_size_bits = %i (0x%x)",
 862                        vol->index_record_size_bits,
 863                        vol->index_record_size_bits);
 864        /* We cannot support index record sizes below the sector size. */
 865        if (vol->index_record_size < vol->sector_size) {
 866                ntfs_error(vol->sb, "Index record size (%i) is smaller than "
 867                                "the sector size (%i).  This is not "
 868                                "supported.  Sorry.", vol->index_record_size,
 869                                vol->sector_size);
 870                return false;
 871        }
 872        /*
 873         * Get the size of the volume in clusters and check for 64-bit-ness.
 874         * Windows currently only uses 32 bits to save the clusters so we do
 875         * the same as it is much faster on 32-bit CPUs.
 876         */
 877        ll = sle64_to_cpu(b->number_of_sectors) >> sectors_per_cluster_bits;
 878        if ((u64)ll >= 1ULL << 32) {
 879                ntfs_error(vol->sb, "Cannot handle 64-bit clusters.  Sorry.");
 880                return false;
 881        }
 882        vol->nr_clusters = ll;
 883        ntfs_debug("vol->nr_clusters = 0x%llx", (long long)vol->nr_clusters);
 884        /*
 885         * On an architecture where unsigned long is 32-bits, we restrict the
 886         * volume size to 2TiB (2^41). On a 64-bit architecture, the compiler
 887         * will hopefully optimize the whole check away.
 888         */
 889        if (sizeof(unsigned long) < 8) {
 890                if ((ll << vol->cluster_size_bits) >= (1ULL << 41)) {
 891                        ntfs_error(vol->sb, "Volume size (%lluTiB) is too "
 892                                        "large for this architecture.  "
 893                                        "Maximum supported is 2TiB.  Sorry.",
 894                                        (unsigned long long)ll >> (40 -
 895                                        vol->cluster_size_bits));
 896                        return false;
 897                }
 898        }
 899        ll = sle64_to_cpu(b->mft_lcn);
 900        if (ll >= vol->nr_clusters) {
 901                ntfs_error(vol->sb, "MFT LCN (%lli, 0x%llx) is beyond end of "
 902                                "volume.  Weird.", (unsigned long long)ll,
 903                                (unsigned long long)ll);
 904                return false;
 905        }
 906        vol->mft_lcn = ll;
 907        ntfs_debug("vol->mft_lcn = 0x%llx", (long long)vol->mft_lcn);
 908        ll = sle64_to_cpu(b->mftmirr_lcn);
 909        if (ll >= vol->nr_clusters) {
 910                ntfs_error(vol->sb, "MFTMirr LCN (%lli, 0x%llx) is beyond end "
 911                                "of volume.  Weird.", (unsigned long long)ll,
 912                                (unsigned long long)ll);
 913                return false;
 914        }
 915        vol->mftmirr_lcn = ll;
 916        ntfs_debug("vol->mftmirr_lcn = 0x%llx", (long long)vol->mftmirr_lcn);
 917#ifdef NTFS_RW
 918        /*
 919         * Work out the size of the mft mirror in number of mft records. If the
 920         * cluster size is less than or equal to the size taken by four mft
 921         * records, the mft mirror stores the first four mft records. If the
 922         * cluster size is bigger than the size taken by four mft records, the
 923         * mft mirror contains as many mft records as will fit into one
 924         * cluster.
 925         */
 926        if (vol->cluster_size <= (4 << vol->mft_record_size_bits))
 927                vol->mftmirr_size = 4;
 928        else
 929                vol->mftmirr_size = vol->cluster_size >>
 930                                vol->mft_record_size_bits;
 931        ntfs_debug("vol->mftmirr_size = %i", vol->mftmirr_size);
 932#endif /* NTFS_RW */
 933        vol->serial_no = le64_to_cpu(b->volume_serial_number);
 934        ntfs_debug("vol->serial_no = 0x%llx",
 935                        (unsigned long long)vol->serial_no);
 936        return true;
 937}
 938
 939/**
 940 * ntfs_setup_allocators - initialize the cluster and mft allocators
 941 * @vol:        volume structure for which to setup the allocators
 942 *
 943 * Setup the cluster (lcn) and mft allocators to the starting values.
 944 */
 945static void ntfs_setup_allocators(ntfs_volume *vol)
 946{
 947#ifdef NTFS_RW
 948        LCN mft_zone_size, mft_lcn;
 949#endif /* NTFS_RW */
 950
 951        ntfs_debug("vol->mft_zone_multiplier = 0x%x",
 952                        vol->mft_zone_multiplier);
 953#ifdef NTFS_RW
 954        /* Determine the size of the MFT zone. */
 955        mft_zone_size = vol->nr_clusters;
 956        switch (vol->mft_zone_multiplier) {  /* % of volume size in clusters */
 957        case 4:
 958                mft_zone_size >>= 1;                    /* 50%   */
 959                break;
 960        case 3:
 961                mft_zone_size = (mft_zone_size +
 962                                (mft_zone_size >> 1)) >> 2;     /* 37.5% */
 963                break;
 964        case 2:
 965                mft_zone_size >>= 2;                    /* 25%   */
 966                break;
 967        /* case 1: */
 968        default:
 969                mft_zone_size >>= 3;                    /* 12.5% */
 970                break;
 971        }
 972        /* Setup the mft zone. */
 973        vol->mft_zone_start = vol->mft_zone_pos = vol->mft_lcn;
 974        ntfs_debug("vol->mft_zone_pos = 0x%llx",
 975                        (unsigned long long)vol->mft_zone_pos);
 976        /*
 977         * Calculate the mft_lcn for an unmodified NTFS volume (see mkntfs
 978         * source) and if the actual mft_lcn is in the expected place or even
 979         * further to the front of the volume, extend the mft_zone to cover the
 980         * beginning of the volume as well.  This is in order to protect the
 981         * area reserved for the mft bitmap as well within the mft_zone itself.
 982         * On non-standard volumes we do not protect it as the overhead would
 983         * be higher than the speed increase we would get by doing it.
 984         */
 985        mft_lcn = (8192 + 2 * vol->cluster_size - 1) / vol->cluster_size;
 986        if (mft_lcn * vol->cluster_size < 16 * 1024)
 987                mft_lcn = (16 * 1024 + vol->cluster_size - 1) /
 988                                vol->cluster_size;
 989        if (vol->mft_zone_start <= mft_lcn)
 990                vol->mft_zone_start = 0;
 991        ntfs_debug("vol->mft_zone_start = 0x%llx",
 992                        (unsigned long long)vol->mft_zone_start);
 993        /*
 994         * Need to cap the mft zone on non-standard volumes so that it does
 995         * not point outside the boundaries of the volume.  We do this by
 996         * halving the zone size until we are inside the volume.
 997         */
 998        vol->mft_zone_end = vol->mft_lcn + mft_zone_size;
 999        while (vol->mft_zone_end >= vol->nr_clusters) {
1000                mft_zone_size >>= 1;
1001                vol->mft_zone_end = vol->mft_lcn + mft_zone_size;
1002        }
1003        ntfs_debug("vol->mft_zone_end = 0x%llx",
1004                        (unsigned long long)vol->mft_zone_end);
1005        /*
1006         * Set the current position within each data zone to the start of the
1007         * respective zone.
1008         */
1009        vol->data1_zone_pos = vol->mft_zone_end;
1010        ntfs_debug("vol->data1_zone_pos = 0x%llx",
1011                        (unsigned long long)vol->data1_zone_pos);
1012        vol->data2_zone_pos = 0;
1013        ntfs_debug("vol->data2_zone_pos = 0x%llx",
1014                        (unsigned long long)vol->data2_zone_pos);
1015
1016        /* Set the mft data allocation position to mft record 24. */
1017        vol->mft_data_pos = 24;
1018        ntfs_debug("vol->mft_data_pos = 0x%llx",
1019                        (unsigned long long)vol->mft_data_pos);
1020#endif /* NTFS_RW */
1021}
1022
1023#ifdef NTFS_RW
1024
1025/**
1026 * load_and_init_mft_mirror - load and setup the mft mirror inode for a volume
1027 * @vol:        ntfs super block describing device whose mft mirror to load
1028 *
1029 * Return 'true' on success or 'false' on error.
1030 */
1031static bool load_and_init_mft_mirror(ntfs_volume *vol)
1032{
1033        struct inode *tmp_ino;
1034        ntfs_inode *tmp_ni;
1035
1036        ntfs_debug("Entering.");
1037        /* Get mft mirror inode. */
1038        tmp_ino = ntfs_iget(vol->sb, FILE_MFTMirr);
1039        if (IS_ERR(tmp_ino) || is_bad_inode(tmp_ino)) {
1040                if (!IS_ERR(tmp_ino))
1041                        iput(tmp_ino);
1042                /* Caller will display error message. */
1043                return false;
1044        }
1045        /*
1046         * Re-initialize some specifics about $MFTMirr's inode as
1047         * ntfs_read_inode() will have set up the default ones.
1048         */
1049        /* Set uid and gid to root. */
1050        tmp_ino->i_uid = GLOBAL_ROOT_UID;
1051        tmp_ino->i_gid = GLOBAL_ROOT_GID;
1052        /* Regular file.  No access for anyone. */
1053        tmp_ino->i_mode = S_IFREG;
1054        /* No VFS initiated operations allowed for $MFTMirr. */
1055        tmp_ino->i_op = &ntfs_empty_inode_ops;
1056        tmp_ino->i_fop = &ntfs_empty_file_ops;
1057        /* Put in our special address space operations. */
1058        tmp_ino->i_mapping->a_ops = &ntfs_mst_aops;
1059        tmp_ni = NTFS_I(tmp_ino);
1060        /* The $MFTMirr, like the $MFT is multi sector transfer protected. */
1061        NInoSetMstProtected(tmp_ni);
1062        NInoSetSparseDisabled(tmp_ni);
1063        /*
1064         * Set up our little cheat allowing us to reuse the async read io
1065         * completion handler for directories.
1066         */
1067        tmp_ni->itype.index.block_size = vol->mft_record_size;
1068        tmp_ni->itype.index.block_size_bits = vol->mft_record_size_bits;
1069        vol->mftmirr_ino = tmp_ino;
1070        ntfs_debug("Done.");
1071        return true;
1072}
1073
1074/**
1075 * check_mft_mirror - compare contents of the mft mirror with the mft
1076 * @vol:        ntfs super block describing device whose mft mirror to check
1077 *
1078 * Return 'true' on success or 'false' on error.
1079 *
1080 * Note, this function also results in the mft mirror runlist being completely
1081 * mapped into memory.  The mft mirror write code requires this and will BUG()
1082 * should it find an unmapped runlist element.
1083 */
1084static bool check_mft_mirror(ntfs_volume *vol)
1085{
1086        struct super_block *sb = vol->sb;
1087        ntfs_inode *mirr_ni;
1088        struct page *mft_page, *mirr_page;
1089        u8 *kmft, *kmirr;
1090        runlist_element *rl, rl2[2];
1091        pgoff_t index;
1092        int mrecs_per_page, i;
1093
1094        ntfs_debug("Entering.");
1095        /* Compare contents of $MFT and $MFTMirr. */
1096        mrecs_per_page = PAGE_CACHE_SIZE / vol->mft_record_size;
1097        BUG_ON(!mrecs_per_page);
1098        BUG_ON(!vol->mftmirr_size);
1099        mft_page = mirr_page = NULL;
1100        kmft = kmirr = NULL;
1101        index = i = 0;
1102        do {
1103                u32 bytes;
1104
1105                /* Switch pages if necessary. */
1106                if (!(i % mrecs_per_page)) {
1107                        if (index) {
1108                                ntfs_unmap_page(mft_page);
1109                                ntfs_unmap_page(mirr_page);
1110                        }
1111                        /* Get the $MFT page. */
1112                        mft_page = ntfs_map_page(vol->mft_ino->i_mapping,
1113                                        index);
1114                        if (IS_ERR(mft_page)) {
1115                                ntfs_error(sb, "Failed to read $MFT.");
1116                                return false;
1117                        }
1118                        kmft = page_address(mft_page);
1119                        /* Get the $MFTMirr page. */
1120                        mirr_page = ntfs_map_page(vol->mftmirr_ino->i_mapping,
1121                                        index);
1122                        if (IS_ERR(mirr_page)) {
1123                                ntfs_error(sb, "Failed to read $MFTMirr.");
1124                                goto mft_unmap_out;
1125                        }
1126                        kmirr = page_address(mirr_page);
1127                        ++index;
1128                }
1129                /* Do not check the record if it is not in use. */
1130                if (((MFT_RECORD*)kmft)->flags & MFT_RECORD_IN_USE) {
1131                        /* Make sure the record is ok. */
1132                        if (ntfs_is_baad_recordp((le32*)kmft)) {
1133                                ntfs_error(sb, "Incomplete multi sector "
1134                                                "transfer detected in mft "
1135                                                "record %i.", i);
1136mm_unmap_out:
1137                                ntfs_unmap_page(mirr_page);
1138mft_unmap_out:
1139                                ntfs_unmap_page(mft_page);
1140                                return false;
1141                        }
1142                }
1143                /* Do not check the mirror record if it is not in use. */
1144                if (((MFT_RECORD*)kmirr)->flags & MFT_RECORD_IN_USE) {
1145                        if (ntfs_is_baad_recordp((le32*)kmirr)) {
1146                                ntfs_error(sb, "Incomplete multi sector "
1147                                                "transfer detected in mft "
1148                                                "mirror record %i.", i);
1149                                goto mm_unmap_out;
1150                        }
1151                }
1152                /* Get the amount of data in the current record. */
1153                bytes = le32_to_cpu(((MFT_RECORD*)kmft)->bytes_in_use);
1154                if (bytes < sizeof(MFT_RECORD_OLD) ||
1155                                bytes > vol->mft_record_size ||
1156                                ntfs_is_baad_recordp((le32*)kmft)) {
1157                        bytes = le32_to_cpu(((MFT_RECORD*)kmirr)->bytes_in_use);
1158                        if (bytes < sizeof(MFT_RECORD_OLD) ||
1159                                        bytes > vol->mft_record_size ||
1160                                        ntfs_is_baad_recordp((le32*)kmirr))
1161                                bytes = vol->mft_record_size;
1162                }
1163                /* Compare the two records. */
1164                if (memcmp(kmft, kmirr, bytes)) {
1165                        ntfs_error(sb, "$MFT and $MFTMirr (record %i) do not "
1166                                        "match.  Run ntfsfix or chkdsk.", i);
1167                        goto mm_unmap_out;
1168                }
1169                kmft += vol->mft_record_size;
1170                kmirr += vol->mft_record_size;
1171        } while (++i < vol->mftmirr_size);
1172        /* Release the last pages. */
1173        ntfs_unmap_page(mft_page);
1174        ntfs_unmap_page(mirr_page);
1175
1176        /* Construct the mft mirror runlist by hand. */
1177        rl2[0].vcn = 0;
1178        rl2[0].lcn = vol->mftmirr_lcn;
1179        rl2[0].length = (vol->mftmirr_size * vol->mft_record_size +
1180                        vol->cluster_size - 1) / vol->cluster_size;
1181        rl2[1].vcn = rl2[0].length;
1182        rl2[1].lcn = LCN_ENOENT;
1183        rl2[1].length = 0;
1184        /*
1185         * Because we have just read all of the mft mirror, we know we have
1186         * mapped the full runlist for it.
1187         */
1188        mirr_ni = NTFS_I(vol->mftmirr_ino);
1189        down_read(&mirr_ni->runlist.lock);
1190        rl = mirr_ni->runlist.rl;
1191        /* Compare the two runlists.  They must be identical. */
1192        i = 0;
1193        do {
1194                if (rl2[i].vcn != rl[i].vcn || rl2[i].lcn != rl[i].lcn ||
1195                                rl2[i].length != rl[i].length) {
1196                        ntfs_error(sb, "$MFTMirr location mismatch.  "
1197                                        "Run chkdsk.");
1198                        up_read(&mirr_ni->runlist.lock);
1199                        return false;
1200                }
1201        } while (rl2[i++].length);
1202        up_read(&mirr_ni->runlist.lock);
1203        ntfs_debug("Done.");
1204        return true;
1205}
1206
1207/**
1208 * load_and_check_logfile - load and check the logfile inode for a volume
1209 * @vol:        ntfs super block describing device whose logfile to load
1210 *
1211 * Return 'true' on success or 'false' on error.
1212 */
1213static bool load_and_check_logfile(ntfs_volume *vol,
1214                RESTART_PAGE_HEADER **rp)
1215{
1216        struct inode *tmp_ino;
1217
1218        ntfs_debug("Entering.");
1219        tmp_ino = ntfs_iget(vol->sb, FILE_LogFile);
1220        if (IS_ERR(tmp_ino) || is_bad_inode(tmp_ino)) {
1221                if (!IS_ERR(tmp_ino))
1222                        iput(tmp_ino);
1223                /* Caller will display error message. */
1224                return false;
1225        }
1226        if (!ntfs_check_logfile(tmp_ino, rp)) {
1227                iput(tmp_ino);
1228                /* ntfs_check_logfile() will have displayed error output. */
1229                return false;
1230        }
1231        NInoSetSparseDisabled(NTFS_I(tmp_ino));
1232        vol->logfile_ino = tmp_ino;
1233        ntfs_debug("Done.");
1234        return true;
1235}
1236
1237#define NTFS_HIBERFIL_HEADER_SIZE       4096
1238
1239/**
1240 * check_windows_hibernation_status - check if Windows is suspended on a volume
1241 * @vol:        ntfs super block of device to check
1242 *
1243 * Check if Windows is hibernated on the ntfs volume @vol.  This is done by
1244 * looking for the file hiberfil.sys in the root directory of the volume.  If
1245 * the file is not present Windows is definitely not suspended.
1246 *
1247 * If hiberfil.sys exists and is less than 4kiB in size it means Windows is
1248 * definitely suspended (this volume is not the system volume).  Caveat:  on a
1249 * system with many volumes it is possible that the < 4kiB check is bogus but
1250 * for now this should do fine.
1251 *
1252 * If hiberfil.sys exists and is larger than 4kiB in size, we need to read the
1253 * hiberfil header (which is the first 4kiB).  If this begins with "hibr",
1254 * Windows is definitely suspended.  If it is completely full of zeroes,
1255 * Windows is definitely not hibernated.  Any other case is treated as if
1256 * Windows is suspended.  This caters for the above mentioned caveat of a
1257 * system with many volumes where no "hibr" magic would be present and there is
1258 * no zero header.
1259 *
1260 * Return 0 if Windows is not hibernated on the volume, >0 if Windows is
1261 * hibernated on the volume, and -errno on error.
1262 */
1263static int check_windows_hibernation_status(ntfs_volume *vol)
1264{
1265        MFT_REF mref;
1266        struct inode *vi;
1267        struct page *page;
1268        u32 *kaddr, *kend;
1269        ntfs_name *name = NULL;
1270        int ret = 1;
1271        static const ntfschar hiberfil[13] = { cpu_to_le16('h'),
1272                        cpu_to_le16('i'), cpu_to_le16('b'),
1273                        cpu_to_le16('e'), cpu_to_le16('r'),
1274                        cpu_to_le16('f'), cpu_to_le16('i'),
1275                        cpu_to_le16('l'), cpu_to_le16('.'),
1276                        cpu_to_le16('s'), cpu_to_le16('y'),
1277                        cpu_to_le16('s'), 0 };
1278
1279        ntfs_debug("Entering.");
1280        /*
1281         * Find the inode number for the hibernation file by looking up the
1282         * filename hiberfil.sys in the root directory.
1283         */
1284        mutex_lock(&vol->root_ino->i_mutex);
1285        mref = ntfs_lookup_inode_by_name(NTFS_I(vol->root_ino), hiberfil, 12,
1286                        &name);
1287        mutex_unlock(&vol->root_ino->i_mutex);
1288        if (IS_ERR_MREF(mref)) {
1289                ret = MREF_ERR(mref);
1290                /* If the file does not exist, Windows is not hibernated. */
1291                if (ret == -ENOENT) {
1292                        ntfs_debug("hiberfil.sys not present.  Windows is not "
1293                                        "hibernated on the volume.");
1294                        return 0;
1295                }
1296                /* A real error occurred. */
1297                ntfs_error(vol->sb, "Failed to find inode number for "
1298                                "hiberfil.sys.");
1299                return ret;
1300        }
1301        /* We do not care for the type of match that was found. */
1302        kfree(name);
1303        /* Get the inode. */
1304        vi = ntfs_iget(vol->sb, MREF(mref));
1305        if (IS_ERR(vi) || is_bad_inode(vi)) {
1306                if (!IS_ERR(vi))
1307                        iput(vi);
1308                ntfs_error(vol->sb, "Failed to load hiberfil.sys.");
1309                return IS_ERR(vi) ? PTR_ERR(vi) : -EIO;
1310        }
1311        if (unlikely(i_size_read(vi) < NTFS_HIBERFIL_HEADER_SIZE)) {
1312                ntfs_debug("hiberfil.sys is smaller than 4kiB (0x%llx).  "
1313                                "Windows is hibernated on the volume.  This "
1314                                "is not the system volume.", i_size_read(vi));
1315                goto iput_out;
1316        }
1317        page = ntfs_map_page(vi->i_mapping, 0);
1318        if (IS_ERR(page)) {
1319                ntfs_error(vol->sb, "Failed to read from hiberfil.sys.");
1320                ret = PTR_ERR(page);
1321                goto iput_out;
1322        }
1323        kaddr = (u32*)page_address(page);
1324        if (*(le32*)kaddr == cpu_to_le32(0x72626968)/*'hibr'*/) {
1325                ntfs_debug("Magic \"hibr\" found in hiberfil.sys.  Windows is "
1326                                "hibernated on the volume.  This is the "
1327                                "system volume.");
1328                goto unm_iput_out;
1329        }
1330        kend = kaddr + NTFS_HIBERFIL_HEADER_SIZE/sizeof(*kaddr);
1331        do {
1332                if (unlikely(*kaddr)) {
1333                        ntfs_debug("hiberfil.sys is larger than 4kiB "
1334                                        "(0x%llx), does not contain the "
1335                                        "\"hibr\" magic, and does not have a "
1336                                        "zero header.  Windows is hibernated "
1337                                        "on the volume.  This is not the "
1338                                        "system volume.", i_size_read(vi));
1339                        goto unm_iput_out;
1340                }
1341        } while (++kaddr < kend);
1342        ntfs_debug("hiberfil.sys contains a zero header.  Windows is not "
1343                        "hibernated on the volume.  This is the system "
1344                        "volume.");
1345        ret = 0;
1346unm_iput_out:
1347        ntfs_unmap_page(page);
1348iput_out:
1349        iput(vi);
1350        return ret;
1351}
1352
1353/**
1354 * load_and_init_quota - load and setup the quota file for a volume if present
1355 * @vol:        ntfs super block describing device whose quota file to load
1356 *
1357 * Return 'true' on success or 'false' on error.  If $Quota is not present, we
1358 * leave vol->quota_ino as NULL and return success.
1359 */
1360static bool load_and_init_quota(ntfs_volume *vol)
1361{
1362        MFT_REF mref;
1363        struct inode *tmp_ino;
1364        ntfs_name *name = NULL;
1365        static const ntfschar Quota[7] = { cpu_to_le16('$'),
1366                        cpu_to_le16('Q'), cpu_to_le16('u'),
1367                        cpu_to_le16('o'), cpu_to_le16('t'),
1368                        cpu_to_le16('a'), 0 };
1369        static ntfschar Q[3] = { cpu_to_le16('$'),
1370                        cpu_to_le16('Q'), 0 };
1371
1372        ntfs_debug("Entering.");
1373        /*
1374         * Find the inode number for the quota file by looking up the filename
1375         * $Quota in the extended system files directory $Extend.
1376         */
1377        mutex_lock(&vol->extend_ino->i_mutex);
1378        mref = ntfs_lookup_inode_by_name(NTFS_I(vol->extend_ino), Quota, 6,
1379                        &name);
1380        mutex_unlock(&vol->extend_ino->i_mutex);
1381        if (IS_ERR_MREF(mref)) {
1382                /*
1383                 * If the file does not exist, quotas are disabled and have
1384                 * never been enabled on this volume, just return success.
1385                 */
1386                if (MREF_ERR(mref) == -ENOENT) {
1387                        ntfs_debug("$Quota not present.  Volume does not have "
1388                                        "quotas enabled.");
1389                        /*
1390                         * No need to try to set quotas out of date if they are
1391                         * not enabled.
1392                         */
1393                        NVolSetQuotaOutOfDate(vol);
1394                        return true;
1395                }
1396                /* A real error occurred. */
1397                ntfs_error(vol->sb, "Failed to find inode number for $Quota.");
1398                return false;
1399        }
1400        /* We do not care for the type of match that was found. */
1401        kfree(name);
1402        /* Get the inode. */
1403        tmp_ino = ntfs_iget(vol->sb, MREF(mref));
1404        if (IS_ERR(tmp_ino) || is_bad_inode(tmp_ino)) {
1405                if (!IS_ERR(tmp_ino))
1406                        iput(tmp_ino);
1407                ntfs_error(vol->sb, "Failed to load $Quota.");
1408                return false;
1409        }
1410        vol->quota_ino = tmp_ino;
1411        /* Get the $Q index allocation attribute. */
1412        tmp_ino = ntfs_index_iget(vol->quota_ino, Q, 2);
1413        if (IS_ERR(tmp_ino)) {
1414                ntfs_error(vol->sb, "Failed to load $Quota/$Q index.");
1415                return false;
1416        }
1417        vol->quota_q_ino = tmp_ino;
1418        ntfs_debug("Done.");
1419        return true;
1420}
1421
1422/**
1423 * load_and_init_usnjrnl - load and setup the transaction log if present
1424 * @vol:        ntfs super block describing device whose usnjrnl file to load
1425 *
1426 * Return 'true' on success or 'false' on error.
1427 *
1428 * If $UsnJrnl is not present or in the process of being disabled, we set
1429 * NVolUsnJrnlStamped() and return success.
1430 *
1431 * If the $UsnJrnl $DATA/$J attribute has a size equal to the lowest valid usn,
1432 * i.e. transaction logging has only just been enabled or the journal has been
1433 * stamped and nothing has been logged since, we also set NVolUsnJrnlStamped()
1434 * and return success.
1435 */
1436static bool load_and_init_usnjrnl(ntfs_volume *vol)
1437{
1438        MFT_REF mref;
1439        struct inode *tmp_ino;
1440        ntfs_inode *tmp_ni;
1441        struct page *page;
1442        ntfs_name *name = NULL;
1443        USN_HEADER *uh;
1444        static const ntfschar UsnJrnl[9] = { cpu_to_le16('$'),
1445                        cpu_to_le16('U'), cpu_to_le16('s'),
1446                        cpu_to_le16('n'), cpu_to_le16('J'),
1447                        cpu_to_le16('r'), cpu_to_le16('n'),
1448                        cpu_to_le16('l'), 0 };
1449        static ntfschar Max[5] = { cpu_to_le16('$'),
1450                        cpu_to_le16('M'), cpu_to_le16('a'),
1451                        cpu_to_le16('x'), 0 };
1452        static ntfschar J[3] = { cpu_to_le16('$'),
1453                        cpu_to_le16('J'), 0 };
1454
1455        ntfs_debug("Entering.");
1456        /*
1457         * Find the inode number for the transaction log file by looking up the
1458         * filename $UsnJrnl in the extended system files directory $Extend.
1459         */
1460        mutex_lock(&vol->extend_ino->i_mutex);
1461        mref = ntfs_lookup_inode_by_name(NTFS_I(vol->extend_ino), UsnJrnl, 8,
1462                        &name);
1463        mutex_unlock(&vol->extend_ino->i_mutex);
1464        if (IS_ERR_MREF(mref)) {
1465                /*
1466                 * If the file does not exist, transaction logging is disabled,
1467                 * just return success.
1468                 */
1469                if (MREF_ERR(mref) == -ENOENT) {
1470                        ntfs_debug("$UsnJrnl not present.  Volume does not "
1471                                        "have transaction logging enabled.");
1472not_enabled:
1473                        /*
1474                         * No need to try to stamp the transaction log if
1475                         * transaction logging is not enabled.
1476                         */
1477                        NVolSetUsnJrnlStamped(vol);
1478                        return true;
1479                }
1480                /* A real error occurred. */
1481                ntfs_error(vol->sb, "Failed to find inode number for "
1482                                "$UsnJrnl.");
1483                return false;
1484        }
1485        /* We do not care for the type of match that was found. */
1486        kfree(name);
1487        /* Get the inode. */
1488        tmp_ino = ntfs_iget(vol->sb, MREF(mref));
1489        if (unlikely(IS_ERR(tmp_ino) || is_bad_inode(tmp_ino))) {
1490                if (!IS_ERR(tmp_ino))
1491                        iput(tmp_ino);
1492                ntfs_error(vol->sb, "Failed to load $UsnJrnl.");
1493                return false;
1494        }
1495        vol->usnjrnl_ino = tmp_ino;
1496        /*
1497         * If the transaction log is in the process of being deleted, we can
1498         * ignore it.
1499         */
1500        if (unlikely(vol->vol_flags & VOLUME_DELETE_USN_UNDERWAY)) {
1501                ntfs_debug("$UsnJrnl in the process of being disabled.  "
1502                                "Volume does not have transaction logging "
1503                                "enabled.");
1504                goto not_enabled;
1505        }
1506        /* Get the $DATA/$Max attribute. */
1507        tmp_ino = ntfs_attr_iget(vol->usnjrnl_ino, AT_DATA, Max, 4);
1508        if (IS_ERR(tmp_ino)) {
1509                ntfs_error(vol->sb, "Failed to load $UsnJrnl/$DATA/$Max "
1510                                "attribute.");
1511                return false;
1512        }
1513        vol->usnjrnl_max_ino = tmp_ino;
1514        if (unlikely(i_size_read(tmp_ino) < sizeof(USN_HEADER))) {
1515                ntfs_error(vol->sb, "Found corrupt $UsnJrnl/$DATA/$Max "
1516                                "attribute (size is 0x%llx but should be at "
1517                                "least 0x%zx bytes).", i_size_read(tmp_ino),
1518                                sizeof(USN_HEADER));
1519                return false;
1520        }
1521        /* Get the $DATA/$J attribute. */
1522        tmp_ino = ntfs_attr_iget(vol->usnjrnl_ino, AT_DATA, J, 2);
1523        if (IS_ERR(tmp_ino)) {
1524                ntfs_error(vol->sb, "Failed to load $UsnJrnl/$DATA/$J "
1525                                "attribute.");
1526                return false;
1527        }
1528        vol->usnjrnl_j_ino = tmp_ino;
1529        /* Verify $J is non-resident and sparse. */
1530        tmp_ni = NTFS_I(vol->usnjrnl_j_ino);
1531        if (unlikely(!NInoNonResident(tmp_ni) || !NInoSparse(tmp_ni))) {
1532                ntfs_error(vol->sb, "$UsnJrnl/$DATA/$J attribute is resident "
1533                                "and/or not sparse.");
1534                return false;
1535        }
1536        /* Read the USN_HEADER from $DATA/$Max. */
1537        page = ntfs_map_page(vol->usnjrnl_max_ino->i_mapping, 0);
1538        if (IS_ERR(page)) {
1539                ntfs_error(vol->sb, "Failed to read from $UsnJrnl/$DATA/$Max "
1540                                "attribute.");
1541                return false;
1542        }
1543        uh = (USN_HEADER*)page_address(page);
1544        /* Sanity check the $Max. */
1545        if (unlikely(sle64_to_cpu(uh->allocation_delta) >
1546                        sle64_to_cpu(uh->maximum_size))) {
1547                ntfs_error(vol->sb, "Allocation delta (0x%llx) exceeds "
1548                                "maximum size (0x%llx).  $UsnJrnl is corrupt.",
1549                                (long long)sle64_to_cpu(uh->allocation_delta),
1550                                (long long)sle64_to_cpu(uh->maximum_size));
1551                ntfs_unmap_page(page);
1552                return false;
1553        }
1554        /*
1555         * If the transaction log has been stamped and nothing has been written
1556         * to it since, we do not need to stamp it.
1557         */
1558        if (unlikely(sle64_to_cpu(uh->lowest_valid_usn) >=
1559                        i_size_read(vol->usnjrnl_j_ino))) {
1560                if (likely(sle64_to_cpu(uh->lowest_valid_usn) ==
1561                                i_size_read(vol->usnjrnl_j_ino))) {
1562                        ntfs_unmap_page(page);
1563                        ntfs_debug("$UsnJrnl is enabled but nothing has been "
1564                                        "logged since it was last stamped.  "
1565                                        "Treating this as if the volume does "
1566                                        "not have transaction logging "
1567                                        "enabled.");
1568                        goto not_enabled;
1569                }
1570                ntfs_error(vol->sb, "$UsnJrnl has lowest valid usn (0x%llx) "
1571                                "which is out of bounds (0x%llx).  $UsnJrnl "
1572                                "is corrupt.",
1573                                (long long)sle64_to_cpu(uh->lowest_valid_usn),
1574                                i_size_read(vol->usnjrnl_j_ino));
1575                ntfs_unmap_page(page);
1576                return false;
1577        }
1578        ntfs_unmap_page(page);
1579        ntfs_debug("Done.");
1580        return true;
1581}
1582
1583/**
1584 * load_and_init_attrdef - load the attribute definitions table for a volume
1585 * @vol:        ntfs super block describing device whose attrdef to load
1586 *
1587 * Return 'true' on success or 'false' on error.
1588 */
1589static bool load_and_init_attrdef(ntfs_volume *vol)
1590{
1591        loff_t i_size;
1592        struct super_block *sb = vol->sb;
1593        struct inode *ino;
1594        struct page *page;
1595        pgoff_t index, max_index;
1596        unsigned int size;
1597
1598        ntfs_debug("Entering.");
1599        /* Read attrdef table and setup vol->attrdef and vol->attrdef_size. */
1600        ino = ntfs_iget(sb, FILE_AttrDef);
1601        if (IS_ERR(ino) || is_bad_inode(ino)) {
1602                if (!IS_ERR(ino))
1603                        iput(ino);
1604                goto failed;
1605        }
1606        NInoSetSparseDisabled(NTFS_I(ino));
1607        /* The size of FILE_AttrDef must be above 0 and fit inside 31 bits. */
1608        i_size = i_size_read(ino);
1609        if (i_size <= 0 || i_size > 0x7fffffff)
1610                goto iput_failed;
1611        vol->attrdef = (ATTR_DEF*)ntfs_malloc_nofs(i_size);
1612        if (!vol->attrdef)
1613                goto iput_failed;
1614        index = 0;
1615        max_index = i_size >> PAGE_CACHE_SHIFT;
1616        size = PAGE_CACHE_SIZE;
1617        while (index < max_index) {
1618                /* Read the attrdef table and copy it into the linear buffer. */
1619read_partial_attrdef_page:
1620                page = ntfs_map_page(ino->i_mapping, index);
1621                if (IS_ERR(page))
1622                        goto free_iput_failed;
1623                memcpy((u8*)vol->attrdef + (index++ << PAGE_CACHE_SHIFT),
1624                                page_address(page), size);
1625                ntfs_unmap_page(page);
1626        };
1627        if (size == PAGE_CACHE_SIZE) {
1628                size = i_size & ~PAGE_CACHE_MASK;
1629                if (size)
1630                        goto read_partial_attrdef_page;
1631        }
1632        vol->attrdef_size = i_size;
1633        ntfs_debug("Read %llu bytes from $AttrDef.", i_size);
1634        iput(ino);
1635        return true;
1636free_iput_failed:
1637        ntfs_free(vol->attrdef);
1638        vol->attrdef = NULL;
1639iput_failed:
1640        iput(ino);
1641failed:
1642        ntfs_error(sb, "Failed to initialize attribute definition table.");
1643        return false;
1644}
1645
1646#endif /* NTFS_RW */
1647
1648/**
1649 * load_and_init_upcase - load the upcase table for an ntfs volume
1650 * @vol:        ntfs super block describing device whose upcase to load
1651 *
1652 * Return 'true' on success or 'false' on error.
1653 */
1654static bool load_and_init_upcase(ntfs_volume *vol)
1655{
1656        loff_t i_size;
1657        struct super_block *sb = vol->sb;
1658        struct inode *ino;
1659        struct page *page;
1660        pgoff_t index, max_index;
1661        unsigned int size;
1662        int i, max;
1663
1664        ntfs_debug("Entering.");
1665        /* Read upcase table and setup vol->upcase and vol->upcase_len. */
1666        ino = ntfs_iget(sb, FILE_UpCase);
1667        if (IS_ERR(ino) || is_bad_inode(ino)) {
1668                if (!IS_ERR(ino))
1669                        iput(ino);
1670                goto upcase_failed;
1671        }
1672        /*
1673         * The upcase size must not be above 64k Unicode characters, must not
1674         * be zero and must be a multiple of sizeof(ntfschar).
1675         */
1676        i_size = i_size_read(ino);
1677        if (!i_size || i_size & (sizeof(ntfschar) - 1) ||
1678                        i_size > 64ULL * 1024 * sizeof(ntfschar))
1679                goto iput_upcase_failed;
1680        vol->upcase = (ntfschar*)ntfs_malloc_nofs(i_size);
1681        if (!vol->upcase)
1682                goto iput_upcase_failed;
1683        index = 0;
1684        max_index = i_size >> PAGE_CACHE_SHIFT;
1685        size = PAGE_CACHE_SIZE;
1686        while (index < max_index) {
1687                /* Read the upcase table and copy it into the linear buffer. */
1688read_partial_upcase_page:
1689                page = ntfs_map_page(ino->i_mapping, index);
1690                if (IS_ERR(page))
1691                        goto iput_upcase_failed;
1692                memcpy((char*)vol->upcase + (index++ << PAGE_CACHE_SHIFT),
1693                                page_address(page), size);
1694                ntfs_unmap_page(page);
1695        };
1696        if (size == PAGE_CACHE_SIZE) {
1697                size = i_size & ~PAGE_CACHE_MASK;
1698                if (size)
1699                        goto read_partial_upcase_page;
1700        }
1701        vol->upcase_len = i_size >> UCHAR_T_SIZE_BITS;
1702        ntfs_debug("Read %llu bytes from $UpCase (expected %zu bytes).",
1703                        i_size, 64 * 1024 * sizeof(ntfschar));
1704        iput(ino);
1705        mutex_lock(&ntfs_lock);
1706        if (!default_upcase) {
1707                ntfs_debug("Using volume specified $UpCase since default is "
1708                                "not present.");
1709                mutex_unlock(&ntfs_lock);
1710                return true;
1711        }
1712        max = default_upcase_len;
1713        if (max > vol->upcase_len)
1714                max = vol->upcase_len;
1715        for (i = 0; i < max; i++)
1716                if (vol->upcase[i] != default_upcase[i])
1717                        break;
1718        if (i == max) {
1719                ntfs_free(vol->upcase);
1720                vol->upcase = default_upcase;
1721                vol->upcase_len = max;
1722                ntfs_nr_upcase_users++;
1723                mutex_unlock(&ntfs_lock);
1724                ntfs_debug("Volume specified $UpCase matches default. Using "
1725                                "default.");
1726                return true;
1727        }
1728        mutex_unlock(&ntfs_lock);
1729        ntfs_debug("Using volume specified $UpCase since it does not match "
1730                        "the default.");
1731        return true;
1732iput_upcase_failed:
1733        iput(ino);
1734        ntfs_free(vol->upcase);
1735        vol->upcase = NULL;
1736upcase_failed:
1737        mutex_lock(&ntfs_lock);
1738        if (default_upcase) {
1739                vol->upcase = default_upcase;
1740                vol->upcase_len = default_upcase_len;
1741                ntfs_nr_upcase_users++;
1742                mutex_unlock(&ntfs_lock);
1743                ntfs_error(sb, "Failed to load $UpCase from the volume. Using "
1744                                "default.");
1745                return true;
1746        }
1747        mutex_unlock(&ntfs_lock);
1748        ntfs_error(sb, "Failed to initialize upcase table.");
1749        return false;
1750}
1751
1752/*
1753 * The lcn and mft bitmap inodes are NTFS-internal inodes with
1754 * their own special locking rules:
1755 */
1756static struct lock_class_key
1757        lcnbmp_runlist_lock_key, lcnbmp_mrec_lock_key,
1758        mftbmp_runlist_lock_key, mftbmp_mrec_lock_key;
1759
1760/**
1761 * load_system_files - open the system files using normal functions
1762 * @vol:        ntfs super block describing device whose system files to load
1763 *
1764 * Open the system files with normal access functions and complete setting up
1765 * the ntfs super block @vol.
1766 *
1767 * Return 'true' on success or 'false' on error.
1768 */
1769static bool load_system_files(ntfs_volume *vol)
1770{
1771        struct super_block *sb = vol->sb;
1772        MFT_RECORD *m;
1773        VOLUME_INFORMATION *vi;
1774        ntfs_attr_search_ctx *ctx;
1775#ifdef NTFS_RW
1776        RESTART_PAGE_HEADER *rp;
1777        int err;
1778#endif /* NTFS_RW */
1779
1780        ntfs_debug("Entering.");
1781#ifdef NTFS_RW
1782        /* Get mft mirror inode compare the contents of $MFT and $MFTMirr. */
1783        if (!load_and_init_mft_mirror(vol) || !check_mft_mirror(vol)) {
1784                static const char *es1 = "Failed to load $MFTMirr";
1785                static const char *es2 = "$MFTMirr does not match $MFT";
1786                static const char *es3 = ".  Run ntfsfix and/or chkdsk.";
1787
1788                /* If a read-write mount, convert it to a read-only mount. */
1789                if (!(sb->s_flags & MS_RDONLY)) {
1790                        if (!(vol->on_errors & (ON_ERRORS_REMOUNT_RO |
1791                                        ON_ERRORS_CONTINUE))) {
1792                                ntfs_error(sb, "%s and neither on_errors="
1793                                                "continue nor on_errors="
1794                                                "remount-ro was specified%s",
1795                                                !vol->mftmirr_ino ? es1 : es2,
1796                                                es3);
1797                                goto iput_mirr_err_out;
1798                        }
1799                        sb->s_flags |= MS_RDONLY;
1800                        ntfs_error(sb, "%s.  Mounting read-only%s",
1801                                        !vol->mftmirr_ino ? es1 : es2, es3);
1802                } else
1803                        ntfs_warning(sb, "%s.  Will not be able to remount "
1804                                        "read-write%s",
1805                                        !vol->mftmirr_ino ? es1 : es2, es3);
1806                /* This will prevent a read-write remount. */
1807                NVolSetErrors(vol);
1808        }
1809#endif /* NTFS_RW */
1810        /* Get mft bitmap attribute inode. */
1811        vol->mftbmp_ino = ntfs_attr_iget(vol->mft_ino, AT_BITMAP, NULL, 0);
1812        if (IS_ERR(vol->mftbmp_ino)) {
1813                ntfs_error(sb, "Failed to load $MFT/$BITMAP attribute.");
1814                goto iput_mirr_err_out;
1815        }
1816        lockdep_set_class(&NTFS_I(vol->mftbmp_ino)->runlist.lock,
1817                           &mftbmp_runlist_lock_key);
1818        lockdep_set_class(&NTFS_I(vol->mftbmp_ino)->mrec_lock,
1819                           &mftbmp_mrec_lock_key);
1820        /* Read upcase table and setup @vol->upcase and @vol->upcase_len. */
1821        if (!load_and_init_upcase(vol))
1822                goto iput_mftbmp_err_out;
1823#ifdef NTFS_RW
1824        /*
1825         * Read attribute definitions table and setup @vol->attrdef and
1826         * @vol->attrdef_size.
1827         */
1828        if (!load_and_init_attrdef(vol))
1829                goto iput_upcase_err_out;
1830#endif /* NTFS_RW */
1831        /*
1832         * Get the cluster allocation bitmap inode and verify the size, no
1833         * need for any locking at this stage as we are already running
1834         * exclusively as we are mount in progress task.
1835         */
1836        vol->lcnbmp_ino = ntfs_iget(sb, FILE_Bitmap);
1837        if (IS_ERR(vol->lcnbmp_ino) || is_bad_inode(vol->lcnbmp_ino)) {
1838                if (!IS_ERR(vol->lcnbmp_ino))
1839                        iput(vol->lcnbmp_ino);
1840                goto bitmap_failed;
1841        }
1842        lockdep_set_class(&NTFS_I(vol->lcnbmp_ino)->runlist.lock,
1843                           &lcnbmp_runlist_lock_key);
1844        lockdep_set_class(&NTFS_I(vol->lcnbmp_ino)->mrec_lock,
1845                           &lcnbmp_mrec_lock_key);
1846
1847        NInoSetSparseDisabled(NTFS_I(vol->lcnbmp_ino));
1848        if ((vol->nr_clusters + 7) >> 3 > i_size_read(vol->lcnbmp_ino)) {
1849                iput(vol->lcnbmp_ino);
1850bitmap_failed:
1851                ntfs_error(sb, "Failed to load $Bitmap.");
1852                goto iput_attrdef_err_out;
1853        }
1854        /*
1855         * Get the volume inode and setup our cache of the volume flags and
1856         * version.
1857         */
1858        vol->vol_ino = ntfs_iget(sb, FILE_Volume);
1859        if (IS_ERR(vol->vol_ino) || is_bad_inode(vol->vol_ino)) {
1860                if (!IS_ERR(vol->vol_ino))
1861                        iput(vol->vol_ino);
1862volume_failed:
1863                ntfs_error(sb, "Failed to load $Volume.");
1864                goto iput_lcnbmp_err_out;
1865        }
1866        m = map_mft_record(NTFS_I(vol->vol_ino));
1867        if (IS_ERR(m)) {
1868iput_volume_failed:
1869                iput(vol->vol_ino);
1870                goto volume_failed;
1871        }
1872        if (!(ctx = ntfs_attr_get_search_ctx(NTFS_I(vol->vol_ino), m))) {
1873                ntfs_error(sb, "Failed to get attribute search context.");
1874                goto get_ctx_vol_failed;
1875        }
1876        if (ntfs_attr_lookup(AT_VOLUME_INFORMATION, NULL, 0, 0, 0, NULL, 0,
1877                        ctx) || ctx->attr->non_resident || ctx->attr->flags) {
1878err_put_vol:
1879                ntfs_attr_put_search_ctx(ctx);
1880get_ctx_vol_failed:
1881                unmap_mft_record(NTFS_I(vol->vol_ino));
1882                goto iput_volume_failed;
1883        }
1884        vi = (VOLUME_INFORMATION*)((char*)ctx->attr +
1885                        le16_to_cpu(ctx->attr->data.resident.value_offset));
1886        /* Some bounds checks. */
1887        if ((u8*)vi < (u8*)ctx->attr || (u8*)vi +
1888                        le32_to_cpu(ctx->attr->data.resident.value_length) >
1889                        (u8*)ctx->attr + le32_to_cpu(ctx->attr->length))
1890                goto err_put_vol;
1891        /* Copy the volume flags and version to the ntfs_volume structure. */
1892        vol->vol_flags = vi->flags;
1893        vol->major_ver = vi->major_ver;
1894        vol->minor_ver = vi->minor_ver;
1895        ntfs_attr_put_search_ctx(ctx);
1896        unmap_mft_record(NTFS_I(vol->vol_ino));
1897        printk(KERN_INFO "NTFS volume version %i.%i.\n", vol->major_ver,
1898                        vol->minor_ver);
1899        if (vol->major_ver < 3 && NVolSparseEnabled(vol)) {
1900                ntfs_warning(vol->sb, "Disabling sparse support due to NTFS "
1901                                "volume version %i.%i (need at least version "
1902                                "3.0).", vol->major_ver, vol->minor_ver);
1903                NVolClearSparseEnabled(vol);
1904        }
1905#ifdef NTFS_RW
1906        /* Make sure that no unsupported volume flags are set. */
1907        if (vol->vol_flags & VOLUME_MUST_MOUNT_RO_MASK) {
1908                static const char *es1a = "Volume is dirty";
1909                static const char *es1b = "Volume has been modified by chkdsk";
1910                static const char *es1c = "Volume has unsupported flags set";
1911                static const char *es2a = ".  Run chkdsk and mount in Windows.";
1912                static const char *es2b = ".  Mount in Windows.";
1913                const char *es1, *es2;
1914
1915                es2 = es2a;
1916                if (vol->vol_flags & VOLUME_IS_DIRTY)
1917                        es1 = es1a;
1918                else if (vol->vol_flags & VOLUME_MODIFIED_BY_CHKDSK) {
1919                        es1 = es1b;
1920                        es2 = es2b;
1921                } else {
1922                        es1 = es1c;
1923                        ntfs_warning(sb, "Unsupported volume flags 0x%x "
1924                                        "encountered.",
1925                                        (unsigned)le16_to_cpu(vol->vol_flags));
1926                }
1927                /* If a read-write mount, convert it to a read-only mount. */
1928                if (!(sb->s_flags & MS_RDONLY)) {
1929                        if (!(vol->on_errors & (ON_ERRORS_REMOUNT_RO |
1930                                        ON_ERRORS_CONTINUE))) {
1931                                ntfs_error(sb, "%s and neither on_errors="
1932                                                "continue nor on_errors="
1933                                                "remount-ro was specified%s",
1934                                                es1, es2);
1935                                goto iput_vol_err_out;
1936                        }
1937                        sb->s_flags |= MS_RDONLY;
1938                        ntfs_error(sb, "%s.  Mounting read-only%s", es1, es2);
1939                } else
1940                        ntfs_warning(sb, "%s.  Will not be able to remount "
1941                                        "read-write%s", es1, es2);
1942                /*
1943                 * Do not set NVolErrors() because ntfs_remount() re-checks the
1944                 * flags which we need to do in case any flags have changed.
1945                 */
1946        }
1947        /*
1948         * Get the inode for the logfile, check it and determine if the volume
1949         * was shutdown cleanly.
1950         */
1951        rp = NULL;
1952        if (!load_and_check_logfile(vol, &rp) ||
1953                        !ntfs_is_logfile_clean(vol->logfile_ino, rp)) {
1954                static const char *es1a = "Failed to load $LogFile";
1955                static const char *es1b = "$LogFile is not clean";
1956                static const char *es2 = ".  Mount in Windows.";
1957                const char *es1;
1958
1959                es1 = !vol->logfile_ino ? es1a : es1b;
1960                /* If a read-write mount, convert it to a read-only mount. */
1961                if (!(sb->s_flags & MS_RDONLY)) {
1962                        if (!(vol->on_errors & (ON_ERRORS_REMOUNT_RO |
1963                                        ON_ERRORS_CONTINUE))) {
1964                                ntfs_error(sb, "%s and neither on_errors="
1965                                                "continue nor on_errors="
1966                                                "remount-ro was specified%s",
1967                                                es1, es2);
1968                                if (vol->logfile_ino) {
1969                                        BUG_ON(!rp);
1970                                        ntfs_free(rp);
1971                                }
1972                                goto iput_logfile_err_out;
1973                        }
1974                        sb->s_flags |= MS_RDONLY;
1975                        ntfs_error(sb, "%s.  Mounting read-only%s", es1, es2);
1976                } else
1977                        ntfs_warning(sb, "%s.  Will not be able to remount "
1978                                        "read-write%s", es1, es2);
1979                /* This will prevent a read-write remount. */
1980                NVolSetErrors(vol);
1981        }
1982        ntfs_free(rp);
1983#endif /* NTFS_RW */
1984        /* Get the root directory inode so we can do path lookups. */
1985        vol->root_ino = ntfs_iget(sb, FILE_root);
1986        if (IS_ERR(vol->root_ino) || is_bad_inode(vol->root_ino)) {
1987                if (!IS_ERR(vol->root_ino))
1988                        iput(vol->root_ino);
1989                ntfs_error(sb, "Failed to load root directory.");
1990                goto iput_logfile_err_out;
1991        }
1992#ifdef NTFS_RW
1993        /*
1994         * Check if Windows is suspended to disk on the target volume.  If it
1995         * is hibernated, we must not write *anything* to the disk so set
1996         * NVolErrors() without setting the dirty volume flag and mount
1997         * read-only.  This will prevent read-write remounting and it will also
1998         * prevent all writes.
1999         */
2000        err = check_windows_hibernation_status(vol);
2001        if (unlikely(err)) {
2002                static const char *es1a = "Failed to determine if Windows is "
2003                                "hibernated";
2004                static const char *es1b = "Windows is hibernated";
2005                static const char *es2 = ".  Run chkdsk.";
2006                const char *es1;
2007
2008                es1 = err < 0 ? es1a : es1b;
2009                /* If a read-write mount, convert it to a read-only mount. */
2010                if (!(sb->s_flags & MS_RDONLY)) {
2011                        if (!(vol->on_errors & (ON_ERRORS_REMOUNT_RO |
2012                                        ON_ERRORS_CONTINUE))) {
2013                                ntfs_error(sb, "%s and neither on_errors="
2014                                                "continue nor on_errors="
2015                                                "remount-ro was specified%s",
2016                                                es1, es2);
2017                                goto iput_root_err_out;
2018                        }
2019                        sb->s_flags |= MS_RDONLY;
2020                        ntfs_error(sb, "%s.  Mounting read-only%s", es1, es2);
2021                } else
2022                        ntfs_warning(sb, "%s.  Will not be able to remount "
2023                                        "read-write%s", es1, es2);
2024                /* This will prevent a read-write remount. */
2025                NVolSetErrors(vol);
2026        }
2027        /* If (still) a read-write mount, mark the volume dirty. */
2028        if (!(sb->s_flags & MS_RDONLY) &&
2029                        ntfs_set_volume_flags(vol, VOLUME_IS_DIRTY)) {
2030                static const char *es1 = "Failed to set dirty bit in volume "
2031                                "information flags";
2032                static const char *es2 = ".  Run chkdsk.";
2033
2034                /* Convert to a read-only mount. */
2035                if (!(vol->on_errors & (ON_ERRORS_REMOUNT_RO |
2036                                ON_ERRORS_CONTINUE))) {
2037                        ntfs_error(sb, "%s and neither on_errors=continue nor "
2038                                        "on_errors=remount-ro was specified%s",
2039                                        es1, es2);
2040                        goto iput_root_err_out;
2041                }
2042                ntfs_error(sb, "%s.  Mounting read-only%s", es1, es2);
2043                sb->s_flags |= MS_RDONLY;
2044                /*
2045                 * Do not set NVolErrors() because ntfs_remount() might manage
2046                 * to set the dirty flag in which case all would be well.
2047                 */
2048        }
2049#if 0
2050        // TODO: Enable this code once we start modifying anything that is
2051        //       different between NTFS 1.2 and 3.x...
2052        /*
2053         * If (still) a read-write mount, set the NT4 compatibility flag on
2054         * newer NTFS version volumes.
2055         */
2056        if (!(sb->s_flags & MS_RDONLY) && (vol->major_ver > 1) &&
2057                        ntfs_set_volume_flags(vol, VOLUME_MOUNTED_ON_NT4)) {
2058                static const char *es1 = "Failed to set NT4 compatibility flag";
2059                static const char *es2 = ".  Run chkdsk.";
2060
2061                /* Convert to a read-only mount. */
2062                if (!(vol->on_errors & (ON_ERRORS_REMOUNT_RO |
2063                                ON_ERRORS_CONTINUE))) {
2064                        ntfs_error(sb, "%s and neither on_errors=continue nor "
2065                                        "on_errors=remount-ro was specified%s",
2066                                        es1, es2);
2067                        goto iput_root_err_out;
2068                }
2069                ntfs_error(sb, "%s.  Mounting read-only%s", es1, es2);
2070                sb->s_flags |= MS_RDONLY;
2071                NVolSetErrors(vol);
2072        }
2073#endif
2074        /* If (still) a read-write mount, empty the logfile. */
2075        if (!(sb->s_flags & MS_RDONLY) &&
2076                        !ntfs_empty_logfile(vol->logfile_ino)) {
2077                static const char *es1 = "Failed to empty $LogFile";
2078                static const char *es2 = ".  Mount in Windows.";
2079
2080                /* Convert to a read-only mount. */
2081                if (!(vol->on_errors & (ON_ERRORS_REMOUNT_RO |
2082                                ON_ERRORS_CONTINUE))) {
2083                        ntfs_error(sb, "%s and neither on_errors=continue nor "
2084                                        "on_errors=remount-ro was specified%s",
2085                                        es1, es2);
2086                        goto iput_root_err_out;
2087                }
2088                ntfs_error(sb, "%s.  Mounting read-only%s", es1, es2);
2089                sb->s_flags |= MS_RDONLY;
2090                NVolSetErrors(vol);
2091        }
2092#endif /* NTFS_RW */
2093        /* If on NTFS versions before 3.0, we are done. */
2094        if (unlikely(vol->major_ver < 3))
2095                return true;
2096        /* NTFS 3.0+ specific initialization. */
2097        /* Get the security descriptors inode. */
2098        vol->secure_ino = ntfs_iget(sb, FILE_Secure);
2099        if (IS_ERR(vol->secure_ino) || is_bad_inode(vol->secure_ino)) {
2100                if (!IS_ERR(vol->secure_ino))
2101                        iput(vol->secure_ino);
2102                ntfs_error(sb, "Failed to load $Secure.");
2103                goto iput_root_err_out;
2104        }
2105        // TODO: Initialize security.
2106        /* Get the extended system files' directory inode. */
2107        vol->extend_ino = ntfs_iget(sb, FILE_Extend);
2108        if (IS_ERR(vol->extend_ino) || is_bad_inode(vol->extend_ino)) {
2109                if (!IS_ERR(vol->extend_ino))
2110                        iput(vol->extend_ino);
2111                ntfs_error(sb, "Failed to load $Extend.");
2112                goto iput_sec_err_out;
2113        }
2114#ifdef NTFS_RW
2115        /* Find the quota file, load it if present, and set it up. */
2116        if (!load_and_init_quota(vol)) {
2117                static const char *es1 = "Failed to load $Quota";
2118                static const char *es2 = ".  Run chkdsk.";
2119
2120                /* If a read-write mount, convert it to a read-only mount. */
2121                if (!(sb->s_flags & MS_RDONLY)) {
2122                        if (!(vol->on_errors & (ON_ERRORS_REMOUNT_RO |
2123                                        ON_ERRORS_CONTINUE))) {
2124                                ntfs_error(sb, "%s and neither on_errors="
2125                                                "continue nor on_errors="
2126                                                "remount-ro was specified%s",
2127                                                es1, es2);
2128                                goto iput_quota_err_out;
2129                        }
2130                        sb->s_flags |= MS_RDONLY;
2131                        ntfs_error(sb, "%s.  Mounting read-only%s", es1, es2);
2132                } else
2133                        ntfs_warning(sb, "%s.  Will not be able to remount "
2134                                        "read-write%s", es1, es2);
2135                /* This will prevent a read-write remount. */
2136                NVolSetErrors(vol);
2137        }
2138        /* If (still) a read-write mount, mark the quotas out of date. */
2139        if (!(sb->s_flags & MS_RDONLY) &&
2140                        !ntfs_mark_quotas_out_of_date(vol)) {
2141                static const char *es1 = "Failed to mark quotas out of date";
2142                static const char *es2 = ".  Run chkdsk.";
2143
2144                /* Convert to a read-only mount. */
2145                if (!(vol->on_errors & (ON_ERRORS_REMOUNT_RO |
2146                                ON_ERRORS_CONTINUE))) {
2147                        ntfs_error(sb, "%s and neither on_errors=continue nor "
2148                                        "on_errors=remount-ro was specified%s",
2149                                        es1, es2);
2150                        goto iput_quota_err_out;
2151                }
2152                ntfs_error(sb, "%s.  Mounting read-only%s", es1, es2);
2153                sb->s_flags |= MS_RDONLY;
2154                NVolSetErrors(vol);
2155        }
2156        /*
2157         * Find the transaction log file ($UsnJrnl), load it if present, check
2158         * it, and set it up.
2159         */
2160        if (!load_and_init_usnjrnl(vol)) {
2161                static const char *es1 = "Failed to load $UsnJrnl";
2162                static const char *es2 = ".  Run chkdsk.";
2163
2164                /* If a read-write mount, convert it to a read-only mount. */
2165                if (!(sb->s_flags & MS_RDONLY)) {
2166                        if (!(vol->on_errors & (ON_ERRORS_REMOUNT_RO |
2167                                        ON_ERRORS_CONTINUE))) {
2168                                ntfs_error(sb, "%s and neither on_errors="
2169                                                "continue nor on_errors="
2170                                                "remount-ro was specified%s",
2171                                                es1, es2);
2172                                goto iput_usnjrnl_err_out;
2173                        }
2174                        sb->s_flags |= MS_RDONLY;
2175                        ntfs_error(sb, "%s.  Mounting read-only%s", es1, es2);
2176                } else
2177                        ntfs_warning(sb, "%s.  Will not be able to remount "
2178                                        "read-write%s", es1, es2);
2179                /* This will prevent a read-write remount. */
2180                NVolSetErrors(vol);
2181        }
2182        /* If (still) a read-write mount, stamp the transaction log. */
2183        if (!(sb->s_flags & MS_RDONLY) && !ntfs_stamp_usnjrnl(vol)) {
2184                static const char *es1 = "Failed to stamp transaction log "
2185                                "($UsnJrnl)";
2186                static const char *es2 = ".  Run chkdsk.";
2187
2188                /* Convert to a read-only mount. */
2189                if (!(vol->on_errors & (ON_ERRORS_REMOUNT_RO |
2190                                ON_ERRORS_CONTINUE))) {
2191                        ntfs_error(sb, "%s and neither on_errors=continue nor "
2192                                        "on_errors=remount-ro was specified%s",
2193                                        es1, es2);
2194                        goto iput_usnjrnl_err_out;
2195                }
2196                ntfs_error(sb, "%s.  Mounting read-only%s", es1, es2);
2197                sb->s_flags |= MS_RDONLY;
2198                NVolSetErrors(vol);
2199        }
2200#endif /* NTFS_RW */
2201        return true;
2202#ifdef NTFS_RW
2203iput_usnjrnl_err_out:
2204        if (vol->usnjrnl_j_ino)
2205                iput(vol->usnjrnl_j_ino);
2206        if (vol->usnjrnl_max_ino)
2207                iput(vol->usnjrnl_max_ino);
2208        if (vol->usnjrnl_ino)
2209                iput(vol->usnjrnl_ino);
2210iput_quota_err_out:
2211        if (vol->quota_q_ino)
2212                iput(vol->quota_q_ino);
2213        if (vol->quota_ino)
2214                iput(vol->quota_ino);
2215        iput(vol->extend_ino);
2216#endif /* NTFS_RW */
2217iput_sec_err_out:
2218        iput(vol->secure_ino);
2219iput_root_err_out:
2220        iput(vol->root_ino);
2221iput_logfile_err_out:
2222#ifdef NTFS_RW
2223        if (vol->logfile_ino)
2224                iput(vol->logfile_ino);
2225iput_vol_err_out:
2226#endif /* NTFS_RW */
2227        iput(vol->vol_ino);
2228iput_lcnbmp_err_out:
2229        iput(vol->lcnbmp_ino);
2230iput_attrdef_err_out:
2231        vol->attrdef_size = 0;
2232        if (vol->attrdef) {
2233                ntfs_free(vol->attrdef);
2234                vol->attrdef = NULL;
2235        }
2236#ifdef NTFS_RW
2237iput_upcase_err_out:
2238#endif /* NTFS_RW */
2239        vol->upcase_len = 0;
2240        mutex_lock(&ntfs_lock);
2241        if (vol->upcase == default_upcase) {
2242                ntfs_nr_upcase_users--;
2243                vol->upcase = NULL;
2244        }
2245        mutex_unlock(&ntfs_lock);
2246        if (vol->upcase) {
2247                ntfs_free(vol->upcase);
2248                vol->upcase = NULL;
2249        }
2250iput_mftbmp_err_out:
2251        iput(vol->mftbmp_ino);
2252iput_mirr_err_out:
2253#ifdef NTFS_RW
2254        if (vol->mftmirr_ino)
2255                iput(vol->mftmirr_ino);
2256#endif /* NTFS_RW */
2257        return false;
2258}
2259
2260/**
2261 * ntfs_put_super - called by the vfs to unmount a volume
2262 * @sb:         vfs superblock of volume to unmount
2263 *
2264 * ntfs_put_super() is called by the VFS (from fs/super.c::do_umount()) when
2265 * the volume is being unmounted (umount system call has been invoked) and it
2266 * releases all inodes and memory belonging to the NTFS specific part of the
2267 * super block.
2268 */
2269static void ntfs_put_super(struct super_block *sb)
2270{
2271        ntfs_volume *vol = NTFS_SB(sb);
2272
2273        ntfs_debug("Entering.");
2274
2275#ifdef NTFS_RW
2276        /*
2277         * Commit all inodes while they are still open in case some of them
2278         * cause others to be dirtied.
2279         */
2280        ntfs_commit_inode(vol->vol_ino);
2281
2282        /* NTFS 3.0+ specific. */
2283        if (vol->major_ver >= 3) {
2284                if (vol->usnjrnl_j_ino)
2285                        ntfs_commit_inode(vol->usnjrnl_j_ino);
2286                if (vol->usnjrnl_max_ino)
2287                        ntfs_commit_inode(vol->usnjrnl_max_ino);
2288                if (vol->usnjrnl_ino)
2289                        ntfs_commit_inode(vol->usnjrnl_ino);
2290                if (vol->quota_q_ino)
2291                        ntfs_commit_inode(vol->quota_q_ino);
2292                if (vol->quota_ino)
2293                        ntfs_commit_inode(vol->quota_ino);
2294                if (vol->extend_ino)
2295                        ntfs_commit_inode(vol->extend_ino);
2296                if (vol->secure_ino)
2297                        ntfs_commit_inode(vol->secure_ino);
2298        }
2299
2300        ntfs_commit_inode(vol->root_ino);
2301
2302        down_write(&vol->lcnbmp_lock);
2303        ntfs_commit_inode(vol->lcnbmp_ino);
2304        up_write(&vol->lcnbmp_lock);
2305
2306        down_write(&vol->mftbmp_lock);
2307        ntfs_commit_inode(vol->mftbmp_ino);
2308        up_write(&vol->mftbmp_lock);
2309
2310        if (vol->logfile_ino)
2311                ntfs_commit_inode(vol->logfile_ino);
2312
2313        if (vol->mftmirr_ino)
2314                ntfs_commit_inode(vol->mftmirr_ino);
2315        ntfs_commit_inode(vol->mft_ino);
2316
2317        /*
2318         * If a read-write mount and no volume errors have occurred, mark the
2319         * volume clean.  Also, re-commit all affected inodes.
2320         */
2321        if (!(sb->s_flags & MS_RDONLY)) {
2322                if (!NVolErrors(vol)) {
2323                        if (ntfs_clear_volume_flags(vol, VOLUME_IS_DIRTY))
2324                                ntfs_warning(sb, "Failed to clear dirty bit "
2325                                                "in volume information "
2326                                                "flags.  Run chkdsk.");
2327                        ntfs_commit_inode(vol->vol_ino);
2328                        ntfs_commit_inode(vol->root_ino);
2329                        if (vol->mftmirr_ino)
2330                                ntfs_commit_inode(vol->mftmirr_ino);
2331                        ntfs_commit_inode(vol->mft_ino);
2332                } else {
2333                        ntfs_warning(sb, "Volume has errors.  Leaving volume "
2334                                        "marked dirty.  Run chkdsk.");
2335                }
2336        }
2337#endif /* NTFS_RW */
2338
2339        iput(vol->vol_ino);
2340        vol->vol_ino = NULL;
2341
2342        /* NTFS 3.0+ specific clean up. */
2343        if (vol->major_ver >= 3) {
2344#ifdef NTFS_RW
2345                if (vol->usnjrnl_j_ino) {
2346                        iput(vol->usnjrnl_j_ino);
2347                        vol->usnjrnl_j_ino = NULL;
2348                }
2349                if (vol->usnjrnl_max_ino) {
2350                        iput(vol->usnjrnl_max_ino);
2351                        vol->usnjrnl_max_ino = NULL;
2352                }
2353                if (vol->usnjrnl_ino) {
2354                        iput(vol->usnjrnl_ino);
2355                        vol->usnjrnl_ino = NULL;
2356                }
2357                if (vol->quota_q_ino) {
2358                        iput(vol->quota_q_ino);
2359                        vol->quota_q_ino = NULL;
2360                }
2361                if (vol->quota_ino) {
2362                        iput(vol->quota_ino);
2363                        vol->quota_ino = NULL;
2364                }
2365#endif /* NTFS_RW */
2366                if (vol->extend_ino) {
2367                        iput(vol->extend_ino);
2368                        vol->extend_ino = NULL;
2369                }
2370                if (vol->secure_ino) {
2371                        iput(vol->secure_ino);
2372                        vol->secure_ino = NULL;
2373                }
2374        }
2375
2376        iput(vol->root_ino);
2377        vol->root_ino = NULL;
2378
2379        down_write(&vol->lcnbmp_lock);
2380        iput(vol->lcnbmp_ino);
2381        vol->lcnbmp_ino = NULL;
2382        up_write(&vol->lcnbmp_lock);
2383
2384        down_write(&vol->mftbmp_lock);
2385        iput(vol->mftbmp_ino);
2386        vol->mftbmp_ino = NULL;
2387        up_write(&vol->mftbmp_lock);
2388
2389#ifdef NTFS_RW
2390        if (vol->logfile_ino) {
2391                iput(vol->logfile_ino);
2392                vol->logfile_ino = NULL;
2393        }
2394        if (vol->mftmirr_ino) {
2395                /* Re-commit the mft mirror and mft just in case. */
2396                ntfs_commit_inode(vol->mftmirr_ino);
2397                ntfs_commit_inode(vol->mft_ino);
2398                iput(vol->mftmirr_ino);
2399                vol->mftmirr_ino = NULL;
2400        }
2401        /*
2402         * We should have no dirty inodes left, due to
2403         * mft.c::ntfs_mft_writepage() cleaning all the dirty pages as
2404         * the underlying mft records are written out and cleaned.
2405         */
2406        ntfs_commit_inode(vol->mft_ino);
2407        write_inode_now(vol->mft_ino, 1);
2408#endif /* NTFS_RW */
2409
2410        iput(vol->mft_ino);
2411        vol->mft_ino = NULL;
2412
2413        /* Throw away the table of attribute definitions. */
2414        vol->attrdef_size = 0;
2415        if (vol->attrdef) {
2416                ntfs_free(vol->attrdef);
2417                vol->attrdef = NULL;
2418        }
2419        vol->upcase_len = 0;
2420        /*
2421         * Destroy the global default upcase table if necessary.  Also decrease
2422         * the number of upcase users if we are a user.
2423         */
2424        mutex_lock(&ntfs_lock);
2425        if (vol->upcase == default_upcase) {
2426                ntfs_nr_upcase_users--;
2427                vol->upcase = NULL;
2428        }
2429        if (!ntfs_nr_upcase_users && default_upcase) {
2430                ntfs_free(default_upcase);
2431                default_upcase = NULL;
2432        }
2433        if (vol->cluster_size <= 4096 && !--ntfs_nr_compression_users)
2434                free_compression_buffers();
2435        mutex_unlock(&ntfs_lock);
2436        if (vol->upcase) {
2437                ntfs_free(vol->upcase);
2438                vol->upcase = NULL;
2439        }
2440
2441        unload_nls(vol->nls_map);
2442
2443        sb->s_fs_info = NULL;
2444        kfree(vol);
2445}
2446
2447/**
2448 * get_nr_free_clusters - return the number of free clusters on a volume
2449 * @vol:        ntfs volume for which to obtain free cluster count
2450 *
2451 * Calculate the number of free clusters on the mounted NTFS volume @vol. We
2452 * actually calculate the number of clusters in use instead because this
2453 * allows us to not care about partial pages as these will be just zero filled
2454 * and hence not be counted as allocated clusters.
2455 *
2456 * The only particularity is that clusters beyond the end of the logical ntfs
2457 * volume will be marked as allocated to prevent errors which means we have to
2458 * discount those at the end. This is important as the cluster bitmap always
2459 * has a size in multiples of 8 bytes, i.e. up to 63 clusters could be outside
2460 * the logical volume and marked in use when they are not as they do not exist.
2461 *
2462 * If any pages cannot be read we assume all clusters in the erroring pages are
2463 * in use. This means we return an underestimate on errors which is better than
2464 * an overestimate.
2465 */
2466static s64 get_nr_free_clusters(ntfs_volume *vol)
2467{
2468        s64 nr_free = vol->nr_clusters;
2469        struct address_space *mapping = vol->lcnbmp_ino->i_mapping;
2470        struct page *page;
2471        pgoff_t index, max_index;
2472
2473        ntfs_debug("Entering.");
2474        /* Serialize accesses to the cluster bitmap. */
2475        down_read(&vol->lcnbmp_lock);
2476        /*
2477         * Convert the number of bits into bytes rounded up, then convert into
2478         * multiples of PAGE_CACHE_SIZE, rounding up so that if we have one
2479         * full and one partial page max_index = 2.
2480         */
2481        max_index = (((vol->nr_clusters + 7) >> 3) + PAGE_CACHE_SIZE - 1) >>
2482                        PAGE_CACHE_SHIFT;
2483        /* Use multiples of 4 bytes, thus max_size is PAGE_CACHE_SIZE / 4. */
2484        ntfs_debug("Reading $Bitmap, max_index = 0x%lx, max_size = 0x%lx.",
2485                        max_index, PAGE_CACHE_SIZE / 4);
2486        for (index = 0; index < max_index; index++) {
2487                unsigned long *kaddr;
2488
2489                /*
2490                 * Read the page from page cache, getting it from backing store
2491                 * if necessary, and increment the use count.
2492                 */
2493                page = read_mapping_page(mapping, index, NULL);
2494                /* Ignore pages which errored synchronously. */
2495                if (IS_ERR(page)) {
2496                        ntfs_debug("read_mapping_page() error. Skipping "
2497                                        "page (index 0x%lx).", index);
2498                        nr_free -= PAGE_CACHE_SIZE * 8;
2499                        continue;
2500                }
2501                kaddr = kmap_atomic(page);
2502                /*
2503                 * Subtract the number of set bits. If this
2504                 * is the last page and it is partial we don't really care as
2505                 * it just means we do a little extra work but it won't affect
2506                 * the result as all out of range bytes are set to zero by
2507                 * ntfs_readpage().
2508                 */
2509                nr_free -= bitmap_weight(kaddr,
2510                                        PAGE_CACHE_SIZE * BITS_PER_BYTE);
2511                kunmap_atomic(kaddr);
2512                page_cache_release(page);
2513        }
2514        ntfs_debug("Finished reading $Bitmap, last index = 0x%lx.", index - 1);
2515        /*
2516         * Fixup for eventual bits outside logical ntfs volume (see function
2517         * description above).
2518         */
2519        if (vol->nr_clusters & 63)
2520                nr_free += 64 - (vol->nr_clusters & 63);
2521        up_read(&vol->lcnbmp_lock);
2522        /* If errors occurred we may well have gone below zero, fix this. */
2523        if (nr_free < 0)
2524                nr_free = 0;
2525        ntfs_debug("Exiting.");
2526        return nr_free;
2527}
2528
2529/**
2530 * __get_nr_free_mft_records - return the number of free inodes on a volume
2531 * @vol:        ntfs volume for which to obtain free inode count
2532 * @nr_free:    number of mft records in filesystem
2533 * @max_index:  maximum number of pages containing set bits
2534 *
2535 * Calculate the number of free mft records (inodes) on the mounted NTFS
2536 * volume @vol. We actually calculate the number of mft records in use instead
2537 * because this allows us to not care about partial pages as these will be just
2538 * zero filled and hence not be counted as allocated mft record.
2539 *
2540 * If any pages cannot be read we assume all mft records in the erroring pages
2541 * are in use. This means we return an underestimate on errors which is better
2542 * than an overestimate.
2543 *
2544 * NOTE: Caller must hold mftbmp_lock rw_semaphore for reading or writing.
2545 */
2546static unsigned long __get_nr_free_mft_records(ntfs_volume *vol,
2547                s64 nr_free, const pgoff_t max_index)
2548{
2549        struct address_space *mapping = vol->mftbmp_ino->i_mapping;
2550        struct page *page;
2551        pgoff_t index;
2552
2553        ntfs_debug("Entering.");
2554        /* Use multiples of 4 bytes, thus max_size is PAGE_CACHE_SIZE / 4. */
2555        ntfs_debug("Reading $MFT/$BITMAP, max_index = 0x%lx, max_size = "
2556                        "0x%lx.", max_index, PAGE_CACHE_SIZE / 4);
2557        for (index = 0; index < max_index; index++) {
2558                unsigned long *kaddr;
2559
2560                /*
2561                 * Read the page from page cache, getting it from backing store
2562                 * if necessary, and increment the use count.
2563                 */
2564                page = read_mapping_page(mapping, index, NULL);
2565                /* Ignore pages which errored synchronously. */
2566                if (IS_ERR(page)) {
2567                        ntfs_debug("read_mapping_page() error. Skipping "
2568                                        "page (index 0x%lx).", index);
2569                        nr_free -= PAGE_CACHE_SIZE * 8;
2570                        continue;
2571                }
2572                kaddr = kmap_atomic(page);
2573                /*
2574                 * Subtract the number of set bits. If this
2575                 * is the last page and it is partial we don't really care as
2576                 * it just means we do a little extra work but it won't affect
2577                 * the result as all out of range bytes are set to zero by
2578                 * ntfs_readpage().
2579                 */
2580                nr_free -= bitmap_weight(kaddr,
2581                                        PAGE_CACHE_SIZE * BITS_PER_BYTE);
2582                kunmap_atomic(kaddr);
2583                page_cache_release(page);
2584        }
2585        ntfs_debug("Finished reading $MFT/$BITMAP, last index = 0x%lx.",
2586                        index - 1);
2587        /* If errors occurred we may well have gone below zero, fix this. */
2588        if (nr_free < 0)
2589                nr_free = 0;
2590        ntfs_debug("Exiting.");
2591        return nr_free;
2592}
2593
2594/**
2595 * ntfs_statfs - return information about mounted NTFS volume
2596 * @dentry:     dentry from mounted volume
2597 * @sfs:        statfs structure in which to return the information
2598 *
2599 * Return information about the mounted NTFS volume @dentry in the statfs structure
2600 * pointed to by @sfs (this is initialized with zeros before ntfs_statfs is
2601 * called). We interpret the values to be correct of the moment in time at
2602 * which we are called. Most values are variable otherwise and this isn't just
2603 * the free values but the totals as well. For example we can increase the
2604 * total number of file nodes if we run out and we can keep doing this until
2605 * there is no more space on the volume left at all.
2606 *
2607 * Called from vfs_statfs which is used to handle the statfs, fstatfs, and
2608 * ustat system calls.
2609 *
2610 * Return 0 on success or -errno on error.
2611 */
2612static int ntfs_statfs(struct dentry *dentry, struct kstatfs *sfs)
2613{
2614        struct super_block *sb = dentry->d_sb;
2615        s64 size;
2616        ntfs_volume *vol = NTFS_SB(sb);
2617        ntfs_inode *mft_ni = NTFS_I(vol->mft_ino);
2618        pgoff_t max_index;
2619        unsigned long flags;
2620
2621        ntfs_debug("Entering.");
2622        /* Type of filesystem. */
2623        sfs->f_type   = NTFS_SB_MAGIC;
2624        /* Optimal transfer block size. */
2625        sfs->f_bsize  = PAGE_CACHE_SIZE;
2626        /*
2627         * Total data blocks in filesystem in units of f_bsize and since
2628         * inodes are also stored in data blocs ($MFT is a file) this is just
2629         * the total clusters.
2630         */
2631        sfs->f_blocks = vol->nr_clusters << vol->cluster_size_bits >>
2632                                PAGE_CACHE_SHIFT;
2633        /* Free data blocks in filesystem in units of f_bsize. */
2634        size          = get_nr_free_clusters(vol) << vol->cluster_size_bits >>
2635                                PAGE_CACHE_SHIFT;
2636        if (size < 0LL)
2637                size = 0LL;
2638        /* Free blocks avail to non-superuser, same as above on NTFS. */
2639        sfs->f_bavail = sfs->f_bfree = size;
2640        /* Serialize accesses to the inode bitmap. */
2641        down_read(&vol->mftbmp_lock);
2642        read_lock_irqsave(&mft_ni->size_lock, flags);
2643        size = i_size_read(vol->mft_ino) >> vol->mft_record_size_bits;
2644        /*
2645         * Convert the maximum number of set bits into bytes rounded up, then
2646         * convert into multiples of PAGE_CACHE_SIZE, rounding up so that if we
2647         * have one full and one partial page max_index = 2.
2648         */
2649        max_index = ((((mft_ni->initialized_size >> vol->mft_record_size_bits)
2650                        + 7) >> 3) + PAGE_CACHE_SIZE - 1) >> PAGE_CACHE_SHIFT;
2651        read_unlock_irqrestore(&mft_ni->size_lock, flags);
2652        /* Number of inodes in filesystem (at this point in time). */
2653        sfs->f_files = size;
2654        /* Free inodes in fs (based on current total count). */
2655        sfs->f_ffree = __get_nr_free_mft_records(vol, size, max_index);
2656        up_read(&vol->mftbmp_lock);
2657        /*
2658         * File system id. This is extremely *nix flavour dependent and even
2659         * within Linux itself all fs do their own thing. I interpret this to
2660         * mean a unique id associated with the mounted fs and not the id
2661         * associated with the filesystem driver, the latter is already given
2662         * by the filesystem type in sfs->f_type. Thus we use the 64-bit
2663         * volume serial number splitting it into two 32-bit parts. We enter
2664         * the least significant 32-bits in f_fsid[0] and the most significant
2665         * 32-bits in f_fsid[1].
2666         */
2667        sfs->f_fsid.val[0] = vol->serial_no & 0xffffffff;
2668        sfs->f_fsid.val[1] = (vol->serial_no >> 32) & 0xffffffff;
2669        /* Maximum length of filenames. */
2670        sfs->f_namelen     = NTFS_MAX_NAME_LEN;
2671        return 0;
2672}
2673
2674#ifdef NTFS_RW
2675static int ntfs_write_inode(struct inode *vi, struct writeback_control *wbc)
2676{
2677        return __ntfs_write_inode(vi, wbc->sync_mode == WB_SYNC_ALL);
2678}
2679#endif
2680
2681/**
2682 * The complete super operations.
2683 */
2684static const struct super_operations ntfs_sops = {
2685        .alloc_inode    = ntfs_alloc_big_inode,   /* VFS: Allocate new inode. */
2686        .destroy_inode  = ntfs_destroy_big_inode, /* VFS: Deallocate inode. */
2687#ifdef NTFS_RW
2688        .write_inode    = ntfs_write_inode,     /* VFS: Write dirty inode to
2689                                                   disk. */
2690#endif /* NTFS_RW */
2691        .put_super      = ntfs_put_super,       /* Syscall: umount. */
2692        .statfs         = ntfs_statfs,          /* Syscall: statfs */
2693        .remount_fs     = ntfs_remount,         /* Syscall: mount -o remount. */
2694        .evict_inode    = ntfs_evict_big_inode, /* VFS: Called when an inode is
2695                                                   removed from memory. */
2696        .show_options   = ntfs_show_options,    /* Show mount options in
2697                                                   proc. */
2698};
2699
2700/**
2701 * ntfs_fill_super - mount an ntfs filesystem
2702 * @sb:         super block of ntfs filesystem to mount
2703 * @opt:        string containing the mount options
2704 * @silent:     silence error output
2705 *
2706 * ntfs_fill_super() is called by the VFS to mount the device described by @sb
2707 * with the mount otions in @data with the NTFS filesystem.
2708 *
2709 * If @silent is true, remain silent even if errors are detected. This is used
2710 * during bootup, when the kernel tries to mount the root filesystem with all
2711 * registered filesystems one after the other until one succeeds. This implies
2712 * that all filesystems except the correct one will quite correctly and
2713 * expectedly return an error, but nobody wants to see error messages when in
2714 * fact this is what is supposed to happen.
2715 *
2716 * NOTE: @sb->s_flags contains the mount options flags.
2717 */
2718static int ntfs_fill_super(struct super_block *sb, void *opt, const int silent)
2719{
2720        ntfs_volume *vol;
2721        struct buffer_head *bh;
2722        struct inode *tmp_ino;
2723        int blocksize, result;
2724
2725        /*
2726         * We do a pretty difficult piece of bootstrap by reading the
2727         * MFT (and other metadata) from disk into memory. We'll only
2728         * release this metadata during umount, so the locking patterns
2729         * observed during bootstrap do not count. So turn off the
2730         * observation of locking patterns (strictly for this context
2731         * only) while mounting NTFS. [The validator is still active
2732         * otherwise, even for this context: it will for example record
2733         * lock class registrations.]
2734         */
2735        lockdep_off();
2736        ntfs_debug("Entering.");
2737#ifndef NTFS_RW
2738        sb->s_flags |= MS_RDONLY;
2739#endif /* ! NTFS_RW */
2740        /* Allocate a new ntfs_volume and place it in sb->s_fs_info. */
2741        sb->s_fs_info = kmalloc(sizeof(ntfs_volume), GFP_NOFS);
2742        vol = NTFS_SB(sb);
2743        if (!vol) {
2744                if (!silent)
2745                        ntfs_error(sb, "Allocation of NTFS volume structure "
2746                                        "failed. Aborting mount...");
2747                lockdep_on();
2748                return -ENOMEM;
2749        }
2750        /* Initialize ntfs_volume structure. */
2751        *vol = (ntfs_volume) {
2752                .sb = sb,
2753                /*
2754                 * Default is group and other don't have any access to files or
2755                 * directories while owner has full access. Further, files by
2756                 * default are not executable but directories are of course
2757                 * browseable.
2758                 */
2759                .fmask = 0177,
2760                .dmask = 0077,
2761        };
2762        init_rwsem(&vol->mftbmp_lock);
2763        init_rwsem(&vol->lcnbmp_lock);
2764
2765        /* By default, enable sparse support. */
2766        NVolSetSparseEnabled(vol);
2767
2768        /* Important to get the mount options dealt with now. */
2769        if (!parse_options(vol, (char*)opt))
2770                goto err_out_now;
2771
2772        /* We support sector sizes up to the PAGE_CACHE_SIZE. */
2773        if (bdev_logical_block_size(sb->s_bdev) > PAGE_CACHE_SIZE) {
2774                if (!silent)
2775                        ntfs_error(sb, "Device has unsupported sector size "
2776                                        "(%i).  The maximum supported sector "
2777                                        "size on this architecture is %lu "
2778                                        "bytes.",
2779                                        bdev_logical_block_size(sb->s_bdev),
2780                                        PAGE_CACHE_SIZE);
2781                goto err_out_now;
2782        }
2783        /*
2784         * Setup the device access block size to NTFS_BLOCK_SIZE or the hard
2785         * sector size, whichever is bigger.
2786         */
2787        blocksize = sb_min_blocksize(sb, NTFS_BLOCK_SIZE);
2788        if (blocksize < NTFS_BLOCK_SIZE) {
2789                if (!silent)
2790                        ntfs_error(sb, "Unable to set device block size.");
2791                goto err_out_now;
2792        }
2793        BUG_ON(blocksize != sb->s_blocksize);
2794        ntfs_debug("Set device block size to %i bytes (block size bits %i).",
2795                        blocksize, sb->s_blocksize_bits);
2796        /* Determine the size of the device in units of block_size bytes. */
2797        if (!i_size_read(sb->s_bdev->bd_inode)) {
2798                if (!silent)
2799                        ntfs_error(sb, "Unable to determine device size.");
2800                goto err_out_now;
2801        }
2802        vol->nr_blocks = i_size_read(sb->s_bdev->bd_inode) >>
2803                        sb->s_blocksize_bits;
2804        /* Read the boot sector and return unlocked buffer head to it. */
2805        if (!(bh = read_ntfs_boot_sector(sb, silent))) {
2806                if (!silent)
2807                        ntfs_error(sb, "Not an NTFS volume.");
2808                goto err_out_now;
2809        }
2810        /*
2811         * Extract the data from the boot sector and setup the ntfs volume
2812         * using it.
2813         */
2814        result = parse_ntfs_boot_sector(vol, (NTFS_BOOT_SECTOR*)bh->b_data);
2815        brelse(bh);
2816        if (!result) {
2817                if (!silent)
2818                        ntfs_error(sb, "Unsupported NTFS filesystem.");
2819                goto err_out_now;
2820        }
2821        /*
2822         * If the boot sector indicates a sector size bigger than the current
2823         * device block size, switch the device block size to the sector size.
2824         * TODO: It may be possible to support this case even when the set
2825         * below fails, we would just be breaking up the i/o for each sector
2826         * into multiple blocks for i/o purposes but otherwise it should just
2827         * work.  However it is safer to leave disabled until someone hits this
2828         * error message and then we can get them to try it without the setting
2829         * so we know for sure that it works.
2830         */
2831        if (vol->sector_size > blocksize) {
2832                blocksize = sb_set_blocksize(sb, vol->sector_size);
2833                if (blocksize != vol->sector_size) {
2834                        if (!silent)
2835                                ntfs_error(sb, "Unable to set device block "
2836                                                "size to sector size (%i).",
2837                                                vol->sector_size);
2838                        goto err_out_now;
2839                }
2840                BUG_ON(blocksize != sb->s_blocksize);
2841                vol->nr_blocks = i_size_read(sb->s_bdev->bd_inode) >>
2842                                sb->s_blocksize_bits;
2843                ntfs_debug("Changed device block size to %i bytes (block size "
2844                                "bits %i) to match volume sector size.",
2845                                blocksize, sb->s_blocksize_bits);
2846        }
2847        /* Initialize the cluster and mft allocators. */
2848        ntfs_setup_allocators(vol);
2849        /* Setup remaining fields in the super block. */
2850        sb->s_magic = NTFS_SB_MAGIC;
2851        /*
2852         * Ntfs allows 63 bits for the file size, i.e. correct would be:
2853         *      sb->s_maxbytes = ~0ULL >> 1;
2854         * But the kernel uses a long as the page cache page index which on
2855         * 32-bit architectures is only 32-bits. MAX_LFS_FILESIZE is kernel
2856         * defined to the maximum the page cache page index can cope with
2857         * without overflowing the index or to 2^63 - 1, whichever is smaller.
2858         */
2859        sb->s_maxbytes = MAX_LFS_FILESIZE;
2860        /* Ntfs measures time in 100ns intervals. */
2861        sb->s_time_gran = 100;
2862        /*
2863         * Now load the metadata required for the page cache and our address
2864         * space operations to function. We do this by setting up a specialised
2865         * read_inode method and then just calling the normal iget() to obtain
2866         * the inode for $MFT which is sufficient to allow our normal inode
2867         * operations and associated address space operations to function.
2868         */
2869        sb->s_op = &ntfs_sops;
2870        tmp_ino = new_inode(sb);
2871        if (!tmp_ino) {
2872                if (!silent)
2873                        ntfs_error(sb, "Failed to load essential metadata.");
2874                goto err_out_now;
2875        }
2876        tmp_ino->i_ino = FILE_MFT;
2877        insert_inode_hash(tmp_ino);
2878        if (ntfs_read_inode_mount(tmp_ino) < 0) {
2879                if (!silent)
2880                        ntfs_error(sb, "Failed to load essential metadata.");
2881                goto iput_tmp_ino_err_out_now;
2882        }
2883        mutex_lock(&ntfs_lock);
2884        /*
2885         * The current mount is a compression user if the cluster size is
2886         * less than or equal 4kiB.
2887         */
2888        if (vol->cluster_size <= 4096 && !ntfs_nr_compression_users++) {
2889                result = allocate_compression_buffers();
2890                if (result) {
2891                        ntfs_error(NULL, "Failed to allocate buffers "
2892                                        "for compression engine.");
2893                        ntfs_nr_compression_users--;
2894                        mutex_unlock(&ntfs_lock);
2895                        goto iput_tmp_ino_err_out_now;
2896                }
2897        }
2898        /*
2899         * Generate the global default upcase table if necessary.  Also
2900         * temporarily increment the number of upcase users to avoid race
2901         * conditions with concurrent (u)mounts.
2902         */
2903        if (!default_upcase)
2904                default_upcase = generate_default_upcase();
2905        ntfs_nr_upcase_users++;
2906        mutex_unlock(&ntfs_lock);
2907        /*
2908         * From now on, ignore @silent parameter. If we fail below this line,
2909         * it will be due to a corrupt fs or a system error, so we report it.
2910         */
2911        /*
2912         * Open the system files with normal access functions and complete
2913         * setting up the ntfs super block.
2914         */
2915        if (!load_system_files(vol)) {
2916                ntfs_error(sb, "Failed to load system files.");
2917                goto unl_upcase_iput_tmp_ino_err_out_now;
2918        }
2919
2920        /* We grab a reference, simulating an ntfs_iget(). */
2921        ihold(vol->root_ino);
2922        if ((sb->s_root = d_make_root(vol->root_ino))) {
2923                ntfs_debug("Exiting, status successful.");
2924                /* Release the default upcase if it has no users. */
2925                mutex_lock(&ntfs_lock);
2926                if (!--ntfs_nr_upcase_users && default_upcase) {
2927                        ntfs_free(default_upcase);
2928                        default_upcase = NULL;
2929                }
2930                mutex_unlock(&ntfs_lock);
2931                sb->s_export_op = &ntfs_export_ops;
2932                lockdep_on();
2933                return 0;
2934        }
2935        ntfs_error(sb, "Failed to allocate root directory.");
2936        /* Clean up after the successful load_system_files() call from above. */
2937        // TODO: Use ntfs_put_super() instead of repeating all this code...
2938        // FIXME: Should mark the volume clean as the error is most likely
2939        //        -ENOMEM.
2940        iput(vol->vol_ino);
2941        vol->vol_ino = NULL;
2942        /* NTFS 3.0+ specific clean up. */
2943        if (vol->major_ver >= 3) {
2944#ifdef NTFS_RW
2945                if (vol->usnjrnl_j_ino) {
2946                        iput(vol->usnjrnl_j_ino);
2947                        vol->usnjrnl_j_ino = NULL;
2948                }
2949                if (vol->usnjrnl_max_ino) {
2950                        iput(vol->usnjrnl_max_ino);
2951                        vol->usnjrnl_max_ino = NULL;
2952                }
2953                if (vol->usnjrnl_ino) {
2954                        iput(vol->usnjrnl_ino);
2955                        vol->usnjrnl_ino = NULL;
2956                }
2957                if (vol->quota_q_ino) {
2958                        iput(vol->quota_q_ino);
2959                        vol->quota_q_ino = NULL;
2960                }
2961                if (vol->quota_ino) {
2962                        iput(vol->quota_ino);
2963                        vol->quota_ino = NULL;
2964                }
2965#endif /* NTFS_RW */
2966                if (vol->extend_ino) {
2967                        iput(vol->extend_ino);
2968                        vol->extend_ino = NULL;
2969                }
2970                if (vol->secure_ino) {
2971                        iput(vol->secure_ino);
2972                        vol->secure_ino = NULL;
2973                }
2974        }
2975        iput(vol->root_ino);
2976        vol->root_ino = NULL;
2977        iput(vol->lcnbmp_ino);
2978        vol->lcnbmp_ino = NULL;
2979        iput(vol->mftbmp_ino);
2980        vol->mftbmp_ino = NULL;
2981#ifdef NTFS_RW
2982        if (vol->logfile_ino) {
2983                iput(vol->logfile_ino);
2984                vol->logfile_ino = NULL;
2985        }
2986        if (vol->mftmirr_ino) {
2987                iput(vol->mftmirr_ino);
2988                vol->mftmirr_ino = NULL;
2989        }
2990#endif /* NTFS_RW */
2991        /* Throw away the table of attribute definitions. */
2992        vol->attrdef_size = 0;
2993        if (vol->attrdef) {
2994                ntfs_free(vol->attrdef);
2995                vol->attrdef = NULL;
2996        }
2997        vol->upcase_len = 0;
2998        mutex_lock(&ntfs_lock);
2999        if (vol->upcase == default_upcase) {
3000                ntfs_nr_upcase_users--;
3001                vol->upcase = NULL;
3002        }
3003        mutex_unlock(&ntfs_lock);
3004        if (vol->upcase) {
3005                ntfs_free(vol->upcase);
3006                vol->upcase = NULL;
3007        }
3008        if (vol->nls_map) {
3009                unload_nls(vol->nls_map);
3010                vol->nls_map = NULL;
3011        }
3012        /* Error exit code path. */
3013unl_upcase_iput_tmp_ino_err_out_now:
3014        /*
3015         * Decrease the number of upcase users and destroy the global default
3016         * upcase table if necessary.
3017         */
3018        mutex_lock(&ntfs_lock);
3019        if (!--ntfs_nr_upcase_users && default_upcase) {
3020                ntfs_free(default_upcase);
3021                default_upcase = NULL;
3022        }
3023        if (vol->cluster_size <= 4096 && !--ntfs_nr_compression_users)
3024                free_compression_buffers();
3025        mutex_unlock(&ntfs_lock);
3026iput_tmp_ino_err_out_now:
3027        iput(tmp_ino);
3028        if (vol->mft_ino && vol->mft_ino != tmp_ino)
3029                iput(vol->mft_ino);
3030        vol->mft_ino = NULL;
3031        /* Errors at this stage are irrelevant. */
3032err_out_now:
3033        sb->s_fs_info = NULL;
3034        kfree(vol);
3035        ntfs_debug("Failed, returning -EINVAL.");
3036        lockdep_on();
3037        return -EINVAL;
3038}
3039
3040/*
3041 * This is a slab cache to optimize allocations and deallocations of Unicode
3042 * strings of the maximum length allowed by NTFS, which is NTFS_MAX_NAME_LEN
3043 * (255) Unicode characters + a terminating NULL Unicode character.
3044 */
3045struct kmem_cache *ntfs_name_cache;
3046
3047/* Slab caches for efficient allocation/deallocation of inodes. */
3048struct kmem_cache *ntfs_inode_cache;
3049struct kmem_cache *ntfs_big_inode_cache;
3050
3051/* Init once constructor for the inode slab cache. */
3052static void ntfs_big_inode_init_once(void *foo)
3053{
3054        ntfs_inode *ni = (ntfs_inode *)foo;
3055
3056        inode_init_once(VFS_I(ni));
3057}
3058
3059/*
3060 * Slab caches to optimize allocations and deallocations of attribute search
3061 * contexts and index contexts, respectively.
3062 */
3063struct kmem_cache *ntfs_attr_ctx_cache;
3064struct kmem_cache *ntfs_index_ctx_cache;
3065
3066/* Driver wide mutex. */
3067DEFINE_MUTEX(ntfs_lock);
3068
3069static struct dentry *ntfs_mount(struct file_system_type *fs_type,
3070        int flags, const char *dev_name, void *data)
3071{
3072        return mount_bdev(fs_type, flags, dev_name, data, ntfs_fill_super);
3073}
3074
3075static struct file_system_type ntfs_fs_type = {
3076        .owner          = THIS_MODULE,
3077        .name           = "ntfs",
3078        .mount          = ntfs_mount,
3079        .kill_sb        = kill_block_super,
3080        .fs_flags       = FS_REQUIRES_DEV,
3081};
3082
3083/* Stable names for the slab caches. */
3084static const char ntfs_index_ctx_cache_name[] = "ntfs_index_ctx_cache";
3085static const char ntfs_attr_ctx_cache_name[] = "ntfs_attr_ctx_cache";
3086static const char ntfs_name_cache_name[] = "ntfs_name_cache";
3087static const char ntfs_inode_cache_name[] = "ntfs_inode_cache";
3088static const char ntfs_big_inode_cache_name[] = "ntfs_big_inode_cache";
3089
3090static int __init init_ntfs_fs(void)
3091{
3092        int err = 0;
3093
3094        /* This may be ugly but it results in pretty output so who cares. (-8 */
3095        printk(KERN_INFO "NTFS driver " NTFS_VERSION " [Flags: R/"
3096#ifdef NTFS_RW
3097                        "W"
3098#else
3099                        "O"
3100#endif
3101#ifdef DEBUG
3102                        " DEBUG"
3103#endif
3104#ifdef MODULE
3105                        " MODULE"
3106#endif
3107                        "].\n");
3108
3109        ntfs_debug("Debug messages are enabled.");
3110
3111        ntfs_index_ctx_cache = kmem_cache_create(ntfs_index_ctx_cache_name,
3112                        sizeof(ntfs_index_context), 0 /* offset */,
3113                        SLAB_HWCACHE_ALIGN, NULL /* ctor */);
3114        if (!ntfs_index_ctx_cache) {
3115                printk(KERN_CRIT "NTFS: Failed to create %s!\n",
3116                                ntfs_index_ctx_cache_name);
3117                goto ictx_err_out;
3118        }
3119        ntfs_attr_ctx_cache = kmem_cache_create(ntfs_attr_ctx_cache_name,
3120                        sizeof(ntfs_attr_search_ctx), 0 /* offset */,
3121                        SLAB_HWCACHE_ALIGN, NULL /* ctor */);
3122        if (!ntfs_attr_ctx_cache) {
3123                printk(KERN_CRIT "NTFS: Failed to create %s!\n",
3124                                ntfs_attr_ctx_cache_name);
3125                goto actx_err_out;
3126        }
3127
3128        ntfs_name_cache = kmem_cache_create(ntfs_name_cache_name,
3129                        (NTFS_MAX_NAME_LEN+1) * sizeof(ntfschar), 0,
3130                        SLAB_HWCACHE_ALIGN, NULL);
3131        if (!ntfs_name_cache) {
3132                printk(KERN_CRIT "NTFS: Failed to create %s!\n",
3133                                ntfs_name_cache_name);
3134                goto name_err_out;
3135        }
3136
3137        ntfs_inode_cache = kmem_cache_create(ntfs_inode_cache_name,
3138                        sizeof(ntfs_inode), 0,
3139                        SLAB_RECLAIM_ACCOUNT|SLAB_MEM_SPREAD, NULL);
3140        if (!ntfs_inode_cache) {
3141                printk(KERN_CRIT "NTFS: Failed to create %s!\n",
3142                                ntfs_inode_cache_name);
3143                goto inode_err_out;
3144        }
3145
3146        ntfs_big_inode_cache = kmem_cache_create(ntfs_big_inode_cache_name,
3147                        sizeof(big_ntfs_inode), 0,
3148                        SLAB_HWCACHE_ALIGN|SLAB_RECLAIM_ACCOUNT|SLAB_MEM_SPREAD,
3149                        ntfs_big_inode_init_once);
3150        if (!ntfs_big_inode_cache) {
3151                printk(KERN_CRIT "NTFS: Failed to create %s!\n",
3152                                ntfs_big_inode_cache_name);
3153                goto big_inode_err_out;
3154        }
3155
3156        /* Register the ntfs sysctls. */
3157        err = ntfs_sysctl(1);
3158        if (err) {
3159                printk(KERN_CRIT "NTFS: Failed to register NTFS sysctls!\n");
3160                goto sysctl_err_out;
3161        }
3162
3163        err = register_filesystem(&ntfs_fs_type);
3164        if (!err) {
3165                ntfs_debug("NTFS driver registered successfully.");
3166                return 0; /* Success! */
3167        }
3168        printk(KERN_CRIT "NTFS: Failed to register NTFS filesystem driver!\n");
3169
3170        /* Unregister the ntfs sysctls. */
3171        ntfs_sysctl(0);
3172sysctl_err_out:
3173        kmem_cache_destroy(ntfs_big_inode_cache);
3174big_inode_err_out:
3175        kmem_cache_destroy(ntfs_inode_cache);
3176inode_err_out:
3177        kmem_cache_destroy(ntfs_name_cache);
3178name_err_out:
3179        kmem_cache_destroy(ntfs_attr_ctx_cache);
3180actx_err_out:
3181        kmem_cache_destroy(ntfs_index_ctx_cache);
3182ictx_err_out:
3183        if (!err) {
3184                printk(KERN_CRIT "NTFS: Aborting NTFS filesystem driver "
3185                                "registration...\n");
3186                err = -ENOMEM;
3187        }
3188        return err;
3189}
3190
3191static void __exit exit_ntfs_fs(void)
3192{
3193        ntfs_debug("Unregistering NTFS driver.");
3194
3195        unregister_filesystem(&ntfs_fs_type);
3196
3197        /*
3198         * Make sure all delayed rcu free inodes are flushed before we
3199         * destroy cache.
3200         */
3201        rcu_barrier();
3202        kmem_cache_destroy(ntfs_big_inode_cache);
3203        kmem_cache_destroy(ntfs_inode_cache);
3204        kmem_cache_destroy(ntfs_name_cache);
3205        kmem_cache_destroy(ntfs_attr_ctx_cache);
3206        kmem_cache_destroy(ntfs_index_ctx_cache);
3207        /* Unregister the ntfs sysctls. */
3208        ntfs_sysctl(0);
3209}
3210
3211MODULE_AUTHOR("Anton Altaparmakov <anton@tuxera.com>");
3212MODULE_DESCRIPTION("NTFS 1.2/3.x driver - Copyright (c) 2001-2011 Anton Altaparmakov and Tuxera Inc.");
3213MODULE_VERSION(NTFS_VERSION);
3214MODULE_LICENSE("GPL");
3215#ifdef DEBUG
3216module_param(debug_msgs, bint, 0);
3217MODULE_PARM_DESC(debug_msgs, "Enable debug messages.");
3218#endif
3219
3220module_init(init_ntfs_fs)
3221module_exit(exit_ntfs_fs)
3222
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