// SPDX-License-Identifier: GPL-2.0-or-later
/*
 * NTFS kernel super block handling.
 *
 * Copyright (c) 2001-2012 Anton Altaparmakov and Tuxera Inc.
 * Copyright (c) 2001,2002 Richard Russon
 * Copyright (c) 2025 LG Electronics Co., Ltd.
 */

#include <linux/blkdev.h>       /* For bdev_logical_block_size(). */
#include <linux/backing-dev.h>
#include <linux/vfs.h>
#include <linux/fs_struct.h>
#include <linux/sched/mm.h>
#include <linux/fs_context.h>
#include <linux/fs_parser.h>

#include "sysctl.h"
#include "logfile.h"
#include "index.h"
#include "ntfs.h"
#include "ea.h"
#include "volume.h"

/* A global default upcase table and a corresponding reference count. */
static __le16 *default_upcase;
static unsigned long ntfs_nr_upcase_users;

static struct workqueue_struct *ntfs_wq;

/* Error constants/strings used in inode.c::ntfs_show_options(). */
enum {
        /* One of these must be present, default is ON_ERRORS_CONTINUE. */
        ON_ERRORS_PANIC = 0x01,
        ON_ERRORS_REMOUNT_RO = 0x02,
        ON_ERRORS_CONTINUE = 0x04,
};

static const struct constant_table ntfs_param_enums[] = {
        { "panic",              ON_ERRORS_PANIC },
        { "remount-ro",         ON_ERRORS_REMOUNT_RO },
        { "continue",           ON_ERRORS_CONTINUE },
        {}
};

enum {
        NATIVE_SYMLINK_RAW,
        NATIVE_SYMLINK_REL,
};

static const struct constant_table ntfs_native_symlink_enums[] = {
        { "raw",                NATIVE_SYMLINK_RAW },
        { "rel",                NATIVE_SYMLINK_REL },
        {}
};

enum {
        SYMLINK_WSL,
        SYMLINK_NATIVE,
};

static const struct constant_table ntfs_symlink_enums[] = {
        { "wsl",                SYMLINK_WSL },
        { "native",             SYMLINK_NATIVE },
        {}
};

enum {
        Opt_uid,
        Opt_gid,
        Opt_umask,
        Opt_dmask,
        Opt_fmask,
        Opt_errors,
        Opt_nls,
        Opt_charset,
        Opt_show_sys_files,
        Opt_show_meta,
        Opt_case_sensitive,
        Opt_disable_sparse,
        Opt_sparse,
        Opt_mft_zone_multiplier,
        Opt_preallocated_size,
        Opt_sys_immutable,
        Opt_nohidden,
        Opt_hide_dot_files,
        Opt_check_windows_names,
        Opt_acl,
        Opt_discard,
        Opt_nocase,
        Opt_native_symlink,
        Opt_symlink,
};

static const struct fs_parameter_spec ntfs_parameters[] = {
        fsparam_u32("uid",                      Opt_uid),
        fsparam_u32("gid",                      Opt_gid),
        fsparam_u32oct("umask",                 Opt_umask),
        fsparam_u32oct("dmask",                 Opt_dmask),
        fsparam_u32oct("fmask",                 Opt_fmask),
        fsparam_string("nls",                   Opt_nls),
        fsparam_string("iocharset",             Opt_charset),
        fsparam_enum("errors",                  Opt_errors, ntfs_param_enums),
        fsparam_flag("show_sys_files",          Opt_show_sys_files),
        fsparam_flag("showmeta",                Opt_show_meta),
        fsparam_flag("case_sensitive",          Opt_case_sensitive),
        fsparam_flag("disable_sparse",          Opt_disable_sparse),
        fsparam_s32("mft_zone_multiplier",      Opt_mft_zone_multiplier),
        fsparam_u64("preallocated_size",        Opt_preallocated_size),
        fsparam_flag("sys_immutable",           Opt_sys_immutable),
        fsparam_flag("nohidden",                Opt_nohidden),
        fsparam_flag("hide_dot_files",          Opt_hide_dot_files),
        fsparam_flag("windows_names",           Opt_check_windows_names),
        fsparam_flag("acl",                     Opt_acl),
        fsparam_flag("discard",                 Opt_discard),
        fsparam_flag("sparse",                  Opt_sparse),
        fsparam_flag("nocase",                  Opt_nocase),
        fsparam_enum("native_symlink",          Opt_native_symlink, ntfs_native_symlink_enums),
        fsparam_enum("symlink",                 Opt_symlink, ntfs_symlink_enums),
        {}
};

static int ntfs_parse_param(struct fs_context *fc, struct fs_parameter *param)
{
        struct ntfs_volume *vol = fc->s_fs_info;
        struct fs_parse_result result;
        int opt;

        opt = fs_parse(fc, ntfs_parameters, param, &result);
        if (opt < 0)
                return opt;

        switch (opt) {
        case Opt_uid:
                vol->uid = make_kuid(current_user_ns(), result.uint_32);
                break;
        case Opt_gid:
                vol->gid = make_kgid(current_user_ns(), result.uint_32);
                break;
        case Opt_umask:
                vol->fmask = vol->dmask = result.uint_32;
                break;
        case Opt_dmask:
                vol->dmask = result.uint_32;
                break;
        case Opt_fmask:
                vol->fmask = result.uint_32;
                break;
        case Opt_errors:
                vol->on_errors = result.uint_32;
                break;
        case Opt_nls:
        case Opt_charset:
                if (vol->nls_map)
                        unload_nls(vol->nls_map);
                vol->nls_map = load_nls(param->string);
                if (!vol->nls_map) {
                        ntfs_error(vol->sb, "Failed to load NLS table '%s'.",
                                   param->string);
                        return -EINVAL;
                }
                break;
        case Opt_mft_zone_multiplier:
                if (vol->mft_zone_multiplier && vol->mft_zone_multiplier !=
                                result.int_32) {
                        ntfs_error(vol->sb, "Cannot change mft_zone_multiplier on remount.");
                        return -EINVAL;
                }
                if (result.int_32 < 1 || result.int_32 > 4) {
                        ntfs_error(vol->sb,
                                "Invalid mft_zone_multiplier. Using default value, i.e. 1.");
                        vol->mft_zone_multiplier = 1;
                } else
                        vol->mft_zone_multiplier = result.int_32;
                break;
        case Opt_show_sys_files:
        case Opt_show_meta:
                if (result.boolean)
                        NVolSetShowSystemFiles(vol);
                else
                        NVolClearShowSystemFiles(vol);
                break;
        case Opt_case_sensitive:
                if (result.boolean)
                        NVolSetCaseSensitive(vol);
                else
                        NVolClearCaseSensitive(vol);
                break;
        case Opt_nocase:
                if (result.boolean)
                        NVolClearCaseSensitive(vol);
                else
                        NVolSetCaseSensitive(vol);
                break;
        case Opt_preallocated_size:
                vol->preallocated_size = (loff_t)result.uint_64;
                break;
        case Opt_sys_immutable:
                if (result.boolean)
                        NVolSetSysImmutable(vol);
                else
                        NVolClearSysImmutable(vol);
                break;
        case Opt_nohidden:
                if (result.boolean)
                        NVolClearShowHiddenFiles(vol);
                else
                        NVolSetShowHiddenFiles(vol);
                break;
        case Opt_hide_dot_files:
                if (result.boolean)
                        NVolSetHideDotFiles(vol);
                else
                        NVolClearHideDotFiles(vol);
                break;
        case Opt_check_windows_names:
                if (result.boolean)
                        NVolSetCheckWindowsNames(vol);
                else
                        NVolClearCheckWindowsNames(vol);
                break;
        case Opt_acl:
#ifdef CONFIG_NTFS_FS_POSIX_ACL
                if (result.boolean)
                        fc->sb_flags |= SB_POSIXACL;
                else
                        fc->sb_flags &= ~SB_POSIXACL;
                break;
#else
                return -EINVAL;
#endif
        case Opt_discard:
                if (result.boolean)
                        NVolSetDiscard(vol);
                else
                        NVolClearDiscard(vol);
                break;
        case Opt_disable_sparse:
                if (result.boolean)
                        NVolSetDisableSparse(vol);
                else
                        NVolClearDisableSparse(vol);
                break;
        case Opt_native_symlink:
                if (result.uint_32 == NATIVE_SYMLINK_REL)
                        NVolSetNativeSymlinkRel(vol);
                else
                        NVolClearNativeSymlinkRel(vol);
                break;
        case Opt_symlink:
                if (result.uint_32 == SYMLINK_NATIVE)
                        NVolSetSymlinkNative(vol);
                else
                        NVolClearSymlinkNative(vol);
                break;
        case Opt_sparse:
                break;
        default:
                return -EINVAL;
        }

        return 0;
}

static int ntfs_reconfigure(struct fs_context *fc)
{
        struct super_block *sb = fc->root->d_sb;
        struct ntfs_volume *vol = NTFS_SB(sb);

        ntfs_debug("Entering with remount");

        sync_filesystem(sb);

        /*
         * For the read-write compiled driver, if we are remounting read-write,
         * make sure there are no volume errors and that no unsupported volume
         * flags are set.  Also, empty the logfile journal as it would become
         * stale as soon as something is written to the volume and mark the
         * volume dirty so that chkdsk is run if the volume is not umounted
         * cleanly.
         *
         * When remounting read-only, mark the volume clean if no volume errors
         * have occurred.
         */
        if (sb_rdonly(sb) && !(fc->sb_flags & SB_RDONLY)) {
                static const char *es = ".  Cannot remount read-write.";

                /* Remounting read-write. */
                if (NVolErrors(vol)) {
                        ntfs_error(sb, "Volume has errors and is read-only%s",
                                        es);
                        return -EROFS;
                }
                if (vol->vol_flags & VOLUME_IS_DIRTY) {
                        ntfs_error(sb, "Volume is dirty and read-only%s", es);
                        return -EROFS;
                }
                if (vol->vol_flags & VOLUME_MODIFIED_BY_CHKDSK) {
                        ntfs_error(sb, "Volume has been modified by chkdsk and is read-only%s", es);
                        return -EROFS;
                }
                if (vol->vol_flags & VOLUME_MUST_MOUNT_RO_MASK) {
                        ntfs_error(sb, "Volume has unsupported flags set (0x%x) and is read-only%s",
                                        le16_to_cpu(vol->vol_flags), es);
                        return -EROFS;
                }
                if (vol->logfile_ino && !ntfs_empty_logfile(vol->logfile_ino)) {
                        ntfs_error(sb, "Failed to empty journal LogFile%s",
                                        es);
                        NVolSetErrors(vol);
                        return -EROFS;
                }
        } else if (!sb_rdonly(sb) && (fc->sb_flags & SB_RDONLY)) {
                /* Remounting read-only. */
                if (!NVolErrors(vol)) {
                        if (ntfs_clear_volume_flags(vol, VOLUME_IS_DIRTY))
                                ntfs_warning(sb,
                                        "Failed to clear dirty bit in volume information flags.  Run chkdsk.");
                }
        }

        ntfs_debug("Done.");
        return 0;
}

const struct option_t on_errors_arr[] = {
        { ON_ERRORS_PANIC,      "panic" },
        { ON_ERRORS_REMOUNT_RO, "remount-ro", },
        { ON_ERRORS_CONTINUE,   "continue", },
        { 0,                    NULL }
};

void ntfs_handle_error(struct super_block *sb)
{
        struct ntfs_volume *vol = NTFS_SB(sb);

        if (sb_rdonly(sb))
                return;

        if (vol->on_errors == ON_ERRORS_REMOUNT_RO) {
                sb->s_flags |= SB_RDONLY;
                pr_crit("(device %s): Filesystem has been set read-only\n",
                        sb->s_id);
        } else if (vol->on_errors == ON_ERRORS_PANIC) {
                panic("ntfs: (device %s): panic from previous error\n",
                      sb->s_id);
        } else if (vol->on_errors == ON_ERRORS_CONTINUE) {
                if (errseq_check(&sb->s_wb_err, vol->wb_err) == -ENODEV) {
                        NVolSetShutdown(vol);
                        vol->wb_err = sb->s_wb_err;
                }
        }
}

/*
 * ntfs_write_volume_flags - write new flags to the volume information flags
 * @vol:        ntfs volume on which to modify the flags
 * @flags:      new flags value for the volume information flags
 *
 * Internal function.  You probably want to use ntfs_{set,clear}_volume_flags()
 * instead (see below).
 *
 * Replace the volume information flags on the volume @vol with the value
 * supplied in @flags.  Note, this overwrites the volume information flags, so
 * make sure to combine the flags you want to modify with the old flags and use
 * the result when calling ntfs_write_volume_flags().
 *
 * Return 0 on success and -errno on error.
 */
static int ntfs_write_volume_flags(struct ntfs_volume *vol, const __le16 flags)
{
        struct ntfs_inode *ni = NTFS_I(vol->vol_ino);
        struct volume_information *vi;
        struct ntfs_attr_search_ctx *ctx;
        int err;

        ntfs_debug("Entering, old flags = 0x%x, new flags = 0x%x.",
                        le16_to_cpu(vol->vol_flags), le16_to_cpu(flags));
        mutex_lock(&ni->mrec_lock);
        if (vol->vol_flags == flags)
                goto done;

        ctx = ntfs_attr_get_search_ctx(ni, NULL);
        if (!ctx) {
                err = -ENOMEM;
                goto put_unm_err_out;
        }

        err = ntfs_attr_lookup(AT_VOLUME_INFORMATION, NULL, 0, 0, 0, NULL, 0,
                        ctx);
        if (err)
                goto put_unm_err_out;

        vi = (struct volume_information *)((u8 *)ctx->attr +
                        le16_to_cpu(ctx->attr->data.resident.value_offset));
        vol->vol_flags = vi->flags = flags;
        mark_mft_record_dirty(ctx->ntfs_ino);
        ntfs_attr_put_search_ctx(ctx);
done:
        mutex_unlock(&ni->mrec_lock);
        ntfs_debug("Done.");
        return 0;
put_unm_err_out:
        if (ctx)
                ntfs_attr_put_search_ctx(ctx);
        mutex_unlock(&ni->mrec_lock);
        ntfs_error(vol->sb, "Failed with error code %i.", -err);
        return err;
}

/*
 * ntfs_set_volume_flags - set bits in the volume information flags
 * @vol:        ntfs volume on which to modify the flags
 * @flags:      flags to set on the volume
 *
 * Set the bits in @flags in the volume information flags on the volume @vol.
 *
 * Return 0 on success and -errno on error.
 */
int ntfs_set_volume_flags(struct ntfs_volume *vol, __le16 flags)
{
        flags &= VOLUME_FLAGS_MASK;
        return ntfs_write_volume_flags(vol, vol->vol_flags | flags);
}

/*
 * ntfs_clear_volume_flags - clear bits in the volume information flags
 * @vol:        ntfs volume on which to modify the flags
 * @flags:      flags to clear on the volume
 *
 * Clear the bits in @flags in the volume information flags on the volume @vol.
 *
 * Return 0 on success and -errno on error.
 */
int ntfs_clear_volume_flags(struct ntfs_volume *vol, __le16 flags)
{
        flags &= VOLUME_FLAGS_MASK;
        flags = vol->vol_flags & cpu_to_le16(~le16_to_cpu(flags));
        return ntfs_write_volume_flags(vol, flags);
}

int ntfs_write_volume_label(struct ntfs_volume *vol, char *label)
{
        struct ntfs_inode *vol_ni = NTFS_I(vol->vol_ino);
        struct ntfs_attr_search_ctx *ctx;
        char *new_label;
        __le16 *uname;
        int uname_len, ret;

        uname_len = ntfs_nlstoucs(vol, label, strlen(label),
                                  &uname, FSLABEL_MAX);
        if (uname_len < 0) {
                ntfs_error(vol->sb,
                        "Failed to convert volume label '%s' to Unicode.",
                        label);
                return uname_len;
        }

        if (uname_len > NTFS_MAX_LABEL_LEN) {
                ntfs_error(vol->sb,
                           "Volume label is too long (max %d characters).",
                           NTFS_MAX_LABEL_LEN);
                kvfree(uname);
                return -EINVAL;
        }

        /*
         * Allocate the in-memory label copy up front. If kstrdup() fails we
         * bail out before touching on-disk metadata, so the in-memory label
         * and the on-disk label stay in sync.
         */
        new_label = kstrdup(label, GFP_KERNEL);
        if (!new_label) {
                kvfree(uname);
                return -ENOMEM;
        }

        mutex_lock(&vol_ni->mrec_lock);
        ctx = ntfs_attr_get_search_ctx(vol_ni, NULL);
        if (!ctx) {
                ret = -ENOMEM;
                goto out;
        }

        ret = ntfs_attr_lookup(AT_VOLUME_NAME, NULL, 0, 0, 0, NULL, 0,
                               ctx);
        if (!ret)
                ret = ntfs_attr_record_rm(ctx);
        else if (ret == -ENOENT)
                ret = 0;
        ntfs_attr_put_search_ctx(ctx);
        if (ret)
                goto out;

        ret = ntfs_resident_attr_record_add(vol_ni, AT_VOLUME_NAME, AT_UNNAMED, 0,
                                            (u8 *)uname, uname_len * sizeof(__le16), 0);
out:
        if (ret >= 0) {
                char *old_label;

                mutex_lock(&vol->volume_label_lock);
                old_label = vol->volume_label;
                vol->volume_label = new_label;
                mutex_unlock(&vol->volume_label_lock);

                kfree(old_label);
                mark_inode_dirty_sync(vol->vol_ino);
                ret = 0;
        }
        mutex_unlock(&vol_ni->mrec_lock);
        kvfree(uname);

        if (ret < 0)
                kfree(new_label);
        return ret;
}

/*
 * is_boot_sector_ntfs - check whether a boot sector is a valid NTFS boot sector
 * @sb:         Super block of the device to which @b belongs.
 * @b:          Boot sector of device @sb to check.
 * @silent:     If 'true', all output will be silenced.
 *
 * is_boot_sector_ntfs() checks whether the boot sector @b is a valid NTFS boot
 * sector. Returns 'true' if it is valid and 'false' if not.
 *
 * @sb is only needed for warning/error output, i.e. it can be NULL when silent
 * is 'true'.
 */
static bool is_boot_sector_ntfs(const struct super_block *sb,
                const struct ntfs_boot_sector *b, const bool silent)
{
        /*
         * Check that checksum == sum of u32 values from b to the checksum
         * field.  If checksum is zero, no checking is done.  We will work when
         * the checksum test fails, since some utilities update the boot sector
         * ignoring the checksum which leaves the checksum out-of-date.  We
         * report a warning if this is the case.
         */
        if ((void *)b < (void *)&b->checksum && b->checksum && !silent) {
                __le32 *u;
                u32 i;

                for (i = 0, u = (__le32 *)b; u < (__le32 *)(&b->checksum); ++u)
                        i += le32_to_cpup(u);
                if (le32_to_cpu(b->checksum) != i)
                        ntfs_warning(sb, "Invalid boot sector checksum.");
        }
        /* Check OEMidentifier is "NTFS    " */
        if (b->oem_id != magicNTFS)
                goto not_ntfs;
        /* Check bytes per sector value is between 256 and 4096. */
        if (le16_to_cpu(b->bpb.bytes_per_sector) < 0x100 ||
            le16_to_cpu(b->bpb.bytes_per_sector) > 0x1000)
                goto not_ntfs;
        /*
         * Check sectors per cluster value is valid and the cluster size
         * is not above the maximum (2MB).
         */
        if (b->bpb.sectors_per_cluster > 0x80 &&
            b->bpb.sectors_per_cluster < 0xf4)
                goto not_ntfs;

        /* Check reserved/unused fields are really zero. */
        if (le16_to_cpu(b->bpb.reserved_sectors) ||
                        le16_to_cpu(b->bpb.root_entries) ||
                        le16_to_cpu(b->bpb.sectors) ||
                        le16_to_cpu(b->bpb.sectors_per_fat) ||
                        le32_to_cpu(b->bpb.large_sectors) || b->bpb.fats)
                goto not_ntfs;
        /* Check clusters per file mft record value is valid. */
        if ((u8)b->clusters_per_mft_record < 0xe1 ||
                        (u8)b->clusters_per_mft_record > 0xf7)
                switch (b->clusters_per_mft_record) {
                case 1: case 2: case 4: case 8: case 16: case 32: case 64:
                        break;
                default:
                        goto not_ntfs;
                }
        /* Check clusters per index block value is valid. */
        if ((u8)b->clusters_per_index_record < 0xe1 ||
                        (u8)b->clusters_per_index_record > 0xf7)
                switch (b->clusters_per_index_record) {
                case 1: case 2: case 4: case 8: case 16: case 32: case 64:
                        break;
                default:
                        goto not_ntfs;
                }
        /*
         * Check for valid end of sector marker. We will work without it, but
         * many BIOSes will refuse to boot from a bootsector if the magic is
         * incorrect, so we emit a warning.
         */
        if (!silent && b->end_of_sector_marker != cpu_to_le16(0xaa55))
                ntfs_warning(sb, "Invalid end of sector marker.");
        return true;
not_ntfs:
        return false;
}

/*
 * read_ntfs_boot_sector - read the NTFS boot sector of a device
 * @sb:         super block of device to read the boot sector from
 * @silent:     if true, suppress all output
 *
 * Reads the boot sector from the device and validates it.
 */
static char *read_ntfs_boot_sector(struct super_block *sb,
                const int silent)
{
        char *boot_sector;

        boot_sector = kzalloc(PAGE_SIZE, GFP_NOFS);
        if (!boot_sector)
                return NULL;

        if (ntfs_bdev_read(sb->s_bdev, boot_sector, 0, PAGE_SIZE)) {
                if (!silent)
                        ntfs_error(sb, "Unable to read primary boot sector.");
                kfree(boot_sector);
                return NULL;
        }

        if (!is_boot_sector_ntfs(sb, (struct ntfs_boot_sector *)boot_sector,
                                 silent)) {
                if (!silent)
                        ntfs_error(sb, "Primary boot sector is invalid.");
                kfree(boot_sector);
                return NULL;
        }

        return boot_sector;
}

/*
 * parse_ntfs_boot_sector - parse the boot sector and store the data in @vol
 * @vol:        volume structure to initialise with data from boot sector
 * @b:          boot sector to parse
 *
 * Parse the ntfs boot sector @b and store all imporant information therein in
 * the ntfs super block @vol.  Return 'true' on success and 'false' on error.
 */
static bool parse_ntfs_boot_sector(struct ntfs_volume *vol,
                const struct ntfs_boot_sector *b)
{
        unsigned int sectors_per_cluster, sectors_per_cluster_bits, nr_hidden_sects;
        int clusters_per_mft_record, clusters_per_index_record;
        s64 ll;

        vol->sector_size = le16_to_cpu(b->bpb.bytes_per_sector);
        vol->sector_size_bits = ffs(vol->sector_size) - 1;
        ntfs_debug("vol->sector_size = %i (0x%x)", vol->sector_size,
                        vol->sector_size);
        ntfs_debug("vol->sector_size_bits = %i (0x%x)", vol->sector_size_bits,
                        vol->sector_size_bits);
        if (vol->sector_size < vol->sb->s_blocksize) {
                ntfs_error(vol->sb,
                        "Sector size (%i) is smaller than the device block size (%lu).  This is not supported.",
                        vol->sector_size, vol->sb->s_blocksize);
                return false;
        }

        if (b->bpb.sectors_per_cluster >= 0xf4)
                sectors_per_cluster = 1U << -(s8)b->bpb.sectors_per_cluster;
        else
                sectors_per_cluster = b->bpb.sectors_per_cluster;
        ntfs_debug("sectors_per_cluster = 0x%x", b->bpb.sectors_per_cluster);
        sectors_per_cluster_bits = ffs(sectors_per_cluster) - 1;
        ntfs_debug("sectors_per_cluster_bits = 0x%x",
                        sectors_per_cluster_bits);
        nr_hidden_sects = le32_to_cpu(b->bpb.hidden_sectors);
        ntfs_debug("number of hidden sectors = 0x%x", nr_hidden_sects);
        vol->cluster_size = vol->sector_size << sectors_per_cluster_bits;
        vol->cluster_size_mask = vol->cluster_size - 1;
        vol->cluster_size_bits = ffs(vol->cluster_size) - 1;
        ntfs_debug("vol->cluster_size = %i (0x%x)", vol->cluster_size,
                        vol->cluster_size);
        ntfs_debug("vol->cluster_size_mask = 0x%x", vol->cluster_size_mask);
        ntfs_debug("vol->cluster_size_bits = %i", vol->cluster_size_bits);
        if (vol->cluster_size < vol->sector_size) {
                ntfs_error(vol->sb,
                        "Cluster size (%i) is smaller than the sector size (%i).  This is not supported.",
                        vol->cluster_size, vol->sector_size);
                return false;
        }
        clusters_per_mft_record = b->clusters_per_mft_record;
        ntfs_debug("clusters_per_mft_record = %i (0x%x)",
                        clusters_per_mft_record, clusters_per_mft_record);
        if (clusters_per_mft_record > 0)
                vol->mft_record_size = vol->cluster_size <<
                                (ffs(clusters_per_mft_record) - 1);
        else
                /*
                 * When mft_record_size < cluster_size, clusters_per_mft_record
                 * = -log2(mft_record_size) bytes. mft_record_size normaly is
                 * 1024 bytes, which is encoded as 0xF6 (-10 in decimal).
                 */
                vol->mft_record_size = 1 << -clusters_per_mft_record;
        vol->mft_record_size_mask = vol->mft_record_size - 1;
        vol->mft_record_size_bits = ffs(vol->mft_record_size) - 1;
        ntfs_debug("vol->mft_record_size = %i (0x%x)", vol->mft_record_size,
                        vol->mft_record_size);
        ntfs_debug("vol->mft_record_size_mask = 0x%x",
                        vol->mft_record_size_mask);
        ntfs_debug("vol->mft_record_size_bits = %i (0x%x)",
                        vol->mft_record_size_bits, vol->mft_record_size_bits);
        /*
         * We cannot support mft record sizes above the PAGE_SIZE since
         * we store $MFT/$DATA, the table of mft records in the page cache.
         */
        if (vol->mft_record_size > PAGE_SIZE) {
                ntfs_error(vol->sb,
                        "Mft record size (%i) exceeds the PAGE_SIZE on your system (%lu).  This is not supported.",
                        vol->mft_record_size, PAGE_SIZE);
                return false;
        }
        /* We cannot support mft record sizes below the sector size. */
        if (vol->mft_record_size < vol->sector_size) {
                ntfs_warning(vol->sb, "Mft record size (%i) is smaller than the sector size (%i).",
                                vol->mft_record_size, vol->sector_size);
        }
        clusters_per_index_record = b->clusters_per_index_record;
        ntfs_debug("clusters_per_index_record = %i (0x%x)",
                        clusters_per_index_record, clusters_per_index_record);
        if (clusters_per_index_record > 0)
                vol->index_record_size = vol->cluster_size <<
                                (ffs(clusters_per_index_record) - 1);
        else
                /*
                 * When index_record_size < cluster_size,
                 * clusters_per_index_record = -log2(index_record_size) bytes.
                 * index_record_size normaly equals 4096 bytes, which is
                 * encoded as 0xF4 (-12 in decimal).
                 */
                vol->index_record_size = 1 << -clusters_per_index_record;
        vol->index_record_size_mask = vol->index_record_size - 1;
        vol->index_record_size_bits = ffs(vol->index_record_size) - 1;
        ntfs_debug("vol->index_record_size = %i (0x%x)",
                        vol->index_record_size, vol->index_record_size);
        ntfs_debug("vol->index_record_size_mask = 0x%x",
                        vol->index_record_size_mask);
        ntfs_debug("vol->index_record_size_bits = %i (0x%x)",
                        vol->index_record_size_bits,
                        vol->index_record_size_bits);
        /* We cannot support index record sizes below the sector size. */
        if (vol->index_record_size < vol->sector_size) {
                ntfs_error(vol->sb,
                           "Index record size (%i) is smaller than the sector size (%i).  This is not supported.",
                           vol->index_record_size, vol->sector_size);
                return false;
        }
        /*
         * Get the size of the volume in clusters and check for 64-bit-ness.
         * Windows currently only uses 32 bits to save the clusters so we do
         * the same as it is much faster on 32-bit CPUs.
         */
        ll = le64_to_cpu(b->number_of_sectors) >> sectors_per_cluster_bits;
        if ((u64)ll >= 1ULL << 32) {
                ntfs_error(vol->sb, "Cannot handle 64-bit clusters.");
                return false;
        }
        vol->nr_clusters = ll;
        ntfs_debug("vol->nr_clusters = 0x%llx", vol->nr_clusters);
        ll = le64_to_cpu(b->mft_lcn);
        if (ll >= vol->nr_clusters) {
                ntfs_error(vol->sb, "MFT LCN (%lli, 0x%llx) is beyond end of volume.  Weird.",
                                ll, ll);
                return false;
        }
        vol->mft_lcn = ll;
        ntfs_debug("vol->mft_lcn = 0x%llx", vol->mft_lcn);
        ll = le64_to_cpu(b->mftmirr_lcn);
        if (ll >= vol->nr_clusters) {
                ntfs_error(vol->sb, "MFTMirr LCN (%lli, 0x%llx) is beyond end of volume.  Weird.",
                                ll, ll);
                return false;
        }
        vol->mftmirr_lcn = ll;
        ntfs_debug("vol->mftmirr_lcn = 0x%llx", vol->mftmirr_lcn);
        /*
         * Work out the size of the mft mirror in number of mft records. If the
         * cluster size is less than or equal to the size taken by four mft
         * records, the mft mirror stores the first four mft records. If the
         * cluster size is bigger than the size taken by four mft records, the
         * mft mirror contains as many mft records as will fit into one
         * cluster.
         */
        if (vol->cluster_size <= (4 << vol->mft_record_size_bits))
                vol->mftmirr_size = 4;
        else
                vol->mftmirr_size = vol->cluster_size >>
                                vol->mft_record_size_bits;
        ntfs_debug("vol->mftmirr_size = %i", vol->mftmirr_size);
        vol->serial_no = le64_to_cpu(b->volume_serial_number);
        ntfs_debug("vol->serial_no = 0x%llx", vol->serial_no);

        vol->sparse_compression_unit = 4;
        if (vol->cluster_size > 4096) {
                switch (vol->cluster_size) {
                case 65536:
                        vol->sparse_compression_unit = 0;
                        break;
                case 32768:
                        vol->sparse_compression_unit = 1;
                        break;
                case 16384:
                        vol->sparse_compression_unit = 2;
                        break;
                case 8192:
                        vol->sparse_compression_unit = 3;
                        break;
                }
        }

        return true;
}

/*
 * ntfs_setup_allocators - initialize the cluster and mft allocators
 * @vol:        volume structure for which to setup the allocators
 *
 * Setup the cluster (lcn) and mft allocators to the starting values.
 */
static void ntfs_setup_allocators(struct ntfs_volume *vol)
{
        s64 mft_zone_size, mft_lcn;

        ntfs_debug("vol->mft_zone_multiplier = 0x%x",
                        vol->mft_zone_multiplier);
        /* Determine the size of the MFT zone. */
        mft_zone_size = vol->nr_clusters;
        switch (vol->mft_zone_multiplier) {  /* % of volume size in clusters */
        case 4:
                mft_zone_size >>= 1;                    /* 50%   */
                break;
        case 3:
                mft_zone_size = (mft_zone_size +
                                (mft_zone_size >> 1)) >> 2;     /* 37.5% */
                break;
        case 2:
                mft_zone_size >>= 2;                    /* 25%   */
                break;
        /* case 1: */
        default:
                mft_zone_size >>= 3;                    /* 12.5% */
                break;
        }
        /* Setup the mft zone. */
        vol->mft_zone_start = vol->mft_zone_pos = vol->mft_lcn;
        ntfs_debug("vol->mft_zone_pos = 0x%llx", vol->mft_zone_pos);
        /*
         * Calculate the mft_lcn for an unmodified NTFS volume (see mkntfs
         * source) and if the actual mft_lcn is in the expected place or even
         * further to the front of the volume, extend the mft_zone to cover the
         * beginning of the volume as well.  This is in order to protect the
         * area reserved for the mft bitmap as well within the mft_zone itself.
         * On non-standard volumes we do not protect it as the overhead would
         * be higher than the speed increase we would get by doing it.
         */
        mft_lcn = NTFS_B_TO_CLU(vol, 8192 + 2 * vol->cluster_size - 1);
        if (mft_lcn * vol->cluster_size < 16 * 1024)
                mft_lcn = (16 * 1024 + vol->cluster_size - 1) >>
                                vol->cluster_size_bits;
        if (vol->mft_zone_start <= mft_lcn)
                vol->mft_zone_start = 0;
        ntfs_debug("vol->mft_zone_start = 0x%llx", vol->mft_zone_start);
        /*
         * Need to cap the mft zone on non-standard volumes so that it does
         * not point outside the boundaries of the volume.  We do this by
         * halving the zone size until we are inside the volume.
         */
        vol->mft_zone_end = vol->mft_lcn + mft_zone_size;
        while (vol->mft_zone_end >= vol->nr_clusters) {
                mft_zone_size >>= 1;
                vol->mft_zone_end = vol->mft_lcn + mft_zone_size;
        }
        ntfs_debug("vol->mft_zone_end = 0x%llx", vol->mft_zone_end);
        /*
         * Set the current position within each data zone to the start of the
         * respective zone.
         */
        vol->data1_zone_pos = vol->mft_zone_end;
        ntfs_debug("vol->data1_zone_pos = 0x%llx", vol->data1_zone_pos);
        vol->data2_zone_pos = 0;
        ntfs_debug("vol->data2_zone_pos = 0x%llx", vol->data2_zone_pos);

        /* Set the mft data allocation position to mft record 24. */
        vol->mft_data_pos = 24;
        ntfs_debug("vol->mft_data_pos = 0x%llx", vol->mft_data_pos);
}

static struct lock_class_key mftmirr_runlist_lock_key,
                             mftmirr_mrec_lock_key;
/*
 * load_and_init_mft_mirror - load and setup the mft mirror inode for a volume
 * @vol:        ntfs super block describing device whose mft mirror to load
 *
 * Return 'true' on success or 'false' on error.
 */
static bool load_and_init_mft_mirror(struct ntfs_volume *vol)
{
        struct inode *tmp_ino;
        struct ntfs_inode *tmp_ni;

        ntfs_debug("Entering.");
        /* Get mft mirror inode. */
        tmp_ino = ntfs_iget(vol->sb, FILE_MFTMirr);
        if (IS_ERR(tmp_ino)) {
                if (!IS_ERR(tmp_ino))
                        iput(tmp_ino);
                /* Caller will display error message. */
                return false;
        }
        lockdep_set_class(&NTFS_I(tmp_ino)->runlist.lock,
                          &mftmirr_runlist_lock_key);
        lockdep_set_class(&NTFS_I(tmp_ino)->mrec_lock,
                          &mftmirr_mrec_lock_key);
        /*
         * Re-initialize some specifics about $MFTMirr's inode as
         * ntfs_read_inode() will have set up the default ones.
         */
        /* Set uid and gid to root. */
        tmp_ino->i_uid = GLOBAL_ROOT_UID;
        tmp_ino->i_gid = GLOBAL_ROOT_GID;
        /* Regular file.  No access for anyone. */
        tmp_ino->i_mode = S_IFREG;
        /* No VFS initiated operations allowed for $MFTMirr. */
        tmp_ino->i_op = &ntfs_empty_inode_ops;
        tmp_ino->i_fop = &ntfs_empty_file_ops;
        /* Put in our special address space operations. */
        tmp_ino->i_mapping->a_ops = &ntfs_aops;
        tmp_ni = NTFS_I(tmp_ino);
        /* The $MFTMirr, like the $MFT is multi sector transfer protected. */
        NInoSetMstProtected(tmp_ni);
        NInoSetSparseDisabled(tmp_ni);
        /*
         * Set up our little cheat allowing us to reuse the async read io
         * completion handler for directories.
         */
        tmp_ni->itype.index.block_size = vol->mft_record_size;
        tmp_ni->itype.index.block_size_bits = vol->mft_record_size_bits;
        vol->mftmirr_ino = tmp_ino;
        ntfs_debug("Done.");
        return true;
}

/*
 * check_mft_mirror - compare contents of the mft mirror with the mft
 * @vol:        ntfs super block describing device whose mft mirror to check
 *
 * Return 'true' on success or 'false' on error.
 *
 * Note, this function also results in the mft mirror runlist being completely
 * mapped into memory.  The mft mirror write code requires this and will BUG()
 * should it find an unmapped runlist element.
 */
static bool check_mft_mirror(struct ntfs_volume *vol)
{
        struct super_block *sb = vol->sb;
        struct ntfs_inode *mirr_ni;
        struct folio *mft_folio = NULL, *mirr_folio = NULL;
        u8 *kmft = NULL, *kmirr = NULL;
        struct runlist_element *rl, rl2[2];
        pgoff_t index;
        int mrecs_per_page, i;

        ntfs_debug("Entering.");
        /* Compare contents of $MFT and $MFTMirr. */
        mrecs_per_page = PAGE_SIZE / vol->mft_record_size;
        index = i = 0;
        do {
                u32 bytes;

                /* Switch pages if necessary. */
                if (!(i % mrecs_per_page)) {
                        if (index) {
                                kunmap_local(kmirr);
                                folio_put(mirr_folio);
                                kunmap_local(kmft);
                                folio_put(mft_folio);
                        }
                        /* Get the $MFT page. */
                        mft_folio = read_mapping_folio(vol->mft_ino->i_mapping,
                                        index, NULL);
                        if (IS_ERR(mft_folio)) {
                                ntfs_error(sb, "Failed to read $MFT.");
                                return false;
                        }
                        kmft = kmap_local_folio(mft_folio, 0);
                        /* Get the $MFTMirr page. */
                        mirr_folio = read_mapping_folio(vol->mftmirr_ino->i_mapping,
                                        index, NULL);
                        if (IS_ERR(mirr_folio)) {
                                ntfs_error(sb, "Failed to read $MFTMirr.");
                                goto mft_unmap_out;
                        }
                        kmirr = kmap_local_folio(mirr_folio, 0);
                        ++index;
                }

                /* Do not check the record if it is not in use. */
                if (((struct mft_record *)kmft)->flags & MFT_RECORD_IN_USE) {
                        /* Make sure the record is ok. */
                        if (ntfs_is_baad_recordp((__le32 *)kmft)) {
                                ntfs_error(sb,
                                        "Incomplete multi sector transfer detected in mft record %i.",
                                        i);
mm_unmap_out:
                                kunmap_local(kmirr);
                                folio_put(mirr_folio);
mft_unmap_out:
                                kunmap_local(kmft);
                                folio_put(mft_folio);
                                return false;
                        }
                }
                /* Do not check the mirror record if it is not in use. */
                if (((struct mft_record *)kmirr)->flags & MFT_RECORD_IN_USE) {
                        if (ntfs_is_baad_recordp((__le32 *)kmirr)) {
                                ntfs_error(sb,
                                        "Incomplete multi sector transfer detected in mft mirror record %i.",
                                        i);
                                goto mm_unmap_out;
                        }
                }
                /* Get the amount of data in the current record. */
                bytes = le32_to_cpu(((struct mft_record *)kmft)->bytes_in_use);
                if (bytes < sizeof(struct mft_record_old) ||
                    bytes > vol->mft_record_size ||
                    ntfs_is_baad_recordp((__le32 *)kmft)) {
                        bytes = le32_to_cpu(((struct mft_record *)kmirr)->bytes_in_use);
                        if (bytes < sizeof(struct mft_record_old) ||
                            bytes > vol->mft_record_size ||
                            ntfs_is_baad_recordp((__le32 *)kmirr))
                                bytes = vol->mft_record_size;
                }
                /* Compare the two records. */
                if (memcmp(kmft, kmirr, bytes)) {
                        ntfs_error(sb,
                                   "$MFT and $MFTMirr record %i do not match.  Run chkdsk.",
                                   i);
                        goto mm_unmap_out;
                }
                kmft += vol->mft_record_size;
                kmirr += vol->mft_record_size;
        } while (++i < vol->mftmirr_size);
        /* Release the last folios. */
        kunmap_local(kmirr);
        folio_put(mirr_folio);
        kunmap_local(kmft);
        folio_put(mft_folio);

        /* Construct the mft mirror runlist by hand. */
        rl2[0].vcn = 0;
        rl2[0].lcn = vol->mftmirr_lcn;
        rl2[0].length = NTFS_B_TO_CLU(vol, vol->mftmirr_size * vol->mft_record_size +
                                vol->cluster_size - 1);
        rl2[1].vcn = rl2[0].length;
        rl2[1].lcn = LCN_ENOENT;
        rl2[1].length = 0;
        /*
         * Because we have just read all of the mft mirror, we know we have
         * mapped the full runlist for it.
         */
        mirr_ni = NTFS_I(vol->mftmirr_ino);
        down_read(&mirr_ni->runlist.lock);
        rl = mirr_ni->runlist.rl;
        /* Compare the two runlists.  They must be identical. */
        i = 0;
        do {
                if (rl2[i].vcn != rl[i].vcn || rl2[i].lcn != rl[i].lcn ||
                                rl2[i].length != rl[i].length) {
                        ntfs_error(sb, "$MFTMirr location mismatch.  Run chkdsk.");
                        up_read(&mirr_ni->runlist.lock);
                        return false;
                }
        } while (rl2[i++].length);
        up_read(&mirr_ni->runlist.lock);
        ntfs_debug("Done.");
        return true;
}

/*
 * load_and_check_logfile - load and check the logfile inode for a volume
 * @vol: ntfs volume to load the logfile for
 * @rp: on success, set to the restart page header
 *
 * Return 0 on success or errno on error.
 */
static int load_and_check_logfile(struct ntfs_volume *vol,
                                  struct restart_page_header **rp)
{
        struct inode *tmp_ino;
        int err = 0;

        ntfs_debug("Entering.");
        tmp_ino = ntfs_iget(vol->sb, FILE_LogFile);
        if (IS_ERR(tmp_ino)) {
                if (!IS_ERR(tmp_ino))
                        iput(tmp_ino);
                /* Caller will display error message. */
                return -ENOENT;
        }
        if (!ntfs_check_logfile(tmp_ino, rp))
                err = -EINVAL;
        NInoSetSparseDisabled(NTFS_I(tmp_ino));
        vol->logfile_ino = tmp_ino;
        ntfs_debug("Done.");
        return err;
}

#define NTFS_HIBERFIL_HEADER_SIZE       4096

/*
 * check_windows_hibernation_status - check if Windows is suspended on a volume
 * @vol:        ntfs super block of device to check
 *
 * Check if Windows is hibernated on the ntfs volume @vol.  This is done by
 * looking for the file hiberfil.sys in the root directory of the volume.  If
 * the file is not present Windows is definitely not suspended.
 *
 * If hiberfil.sys exists and is less than 4kiB in size it means Windows is
 * definitely suspended (this volume is not the system volume).  Caveat:  on a
 * system with many volumes it is possible that the < 4kiB check is bogus but
 * for now this should do fine.
 *
 * If hiberfil.sys exists and is larger than 4kiB in size, we need to read the
 * hiberfil header (which is the first 4kiB).  If this begins with "hibr",
 * Windows is definitely suspended.  If it is completely full of zeroes,
 * Windows is definitely not hibernated.  Any other case is treated as if
 * Windows is suspended.  This caters for the above mentioned caveat of a
 * system with many volumes where no "hibr" magic would be present and there is
 * no zero header.
 *
 * Return 0 if Windows is not hibernated on the volume, >0 if Windows is
 * hibernated on the volume, and -errno on error.
 */
static int check_windows_hibernation_status(struct ntfs_volume *vol)
{
        static const __le16 hiberfil[13] = { cpu_to_le16('h'),
                        cpu_to_le16('i'), cpu_to_le16('b'),
                        cpu_to_le16('e'), cpu_to_le16('r'),
                        cpu_to_le16('f'), cpu_to_le16('i'),
                        cpu_to_le16('l'), cpu_to_le16('.'),
                        cpu_to_le16('s'), cpu_to_le16('y'),
                        cpu_to_le16('s'), 0 };
        u64 mref;
        struct inode *vi;
        struct folio *folio;
        u32 *kaddr, *kend, *start_addr = NULL;
        struct ntfs_name *name = NULL;
        int ret = 1;

        ntfs_debug("Entering.");
        /*
         * Find the inode number for the hibernation file by looking up the
         * filename hiberfil.sys in the root directory.
         */
        inode_lock(vol->root_ino);
        mref = ntfs_lookup_inode_by_name(NTFS_I(vol->root_ino), hiberfil, 12,
                        &name);
        inode_unlock(vol->root_ino);
        kfree(name);
        if (IS_ERR_MREF(mref)) {
                ret = MREF_ERR(mref);
                /* If the file does not exist, Windows is not hibernated. */
                if (ret == -ENOENT) {
                        ntfs_debug("hiberfil.sys not present.  Windows is not hibernated on the volume.");
                        return 0;
                }
                /* A real error occurred. */
                ntfs_error(vol->sb, "Failed to find inode number for hiberfil.sys.");
                return ret;
        }
        /* Get the inode. */
        vi = ntfs_iget(vol->sb, MREF(mref));
        if (IS_ERR(vi)) {
                if (!IS_ERR(vi))
                        iput(vi);
                ntfs_error(vol->sb, "Failed to load hiberfil.sys.");
                return IS_ERR(vi) ? PTR_ERR(vi) : -EIO;
        }
        if (unlikely(i_size_read(vi) < NTFS_HIBERFIL_HEADER_SIZE)) {
                ntfs_debug("hiberfil.sys is smaller than 4kiB (0x%llx).  Windows is hibernated on the volume.  This is not the system volume.",
                                i_size_read(vi));
                goto iput_out;
        }

        folio = read_mapping_folio(vi->i_mapping, 0, NULL);
        if (IS_ERR(folio)) {
                ntfs_error(vol->sb, "Failed to read from hiberfil.sys.");
                ret = PTR_ERR(folio);
                goto iput_out;
        }
        start_addr = (u32 *)kmap_local_folio(folio, 0);
        kaddr = start_addr;
        if (*(__le32 *)kaddr == cpu_to_le32(0x72626968)/*'hibr'*/) {
                ntfs_debug("Magic \"hibr\" found in hiberfil.sys.  Windows is hibernated on the volume.  This is the system volume.");
                goto unm_iput_out;
        }
        kend = kaddr + NTFS_HIBERFIL_HEADER_SIZE/sizeof(*kaddr);
        do {
                if (unlikely(*kaddr)) {
                        ntfs_debug("hiberfil.sys is larger than 4kiB (0x%llx), does not contain the \"hibr\" magic, and does not have a zero header.  Windows is hibernated on the volume.  This is not the system volume.",
                                        i_size_read(vi));
                        goto unm_iput_out;
                }
        } while (++kaddr < kend);
        ntfs_debug("hiberfil.sys contains a zero header.  Windows is not hibernated on the volume.  This is the system volume.");
        ret = 0;
unm_iput_out:
        kunmap_local(start_addr);
        folio_put(folio);
iput_out:
        iput(vi);
        return ret;
}

/*
 * load_and_init_attrdef - load the attribute definitions table for a volume
 * @vol:        ntfs super block describing device whose attrdef to load
 *
 * Return 'true' on success or 'false' on error.
 */
static bool load_and_init_attrdef(struct ntfs_volume *vol)
{
        loff_t i_size;
        struct super_block *sb = vol->sb;
        struct inode *ino;
        struct folio *folio;
        u8 *addr;
        pgoff_t index, max_index;
        unsigned int size;

        ntfs_debug("Entering.");
        /* Read attrdef table and setup vol->attrdef and vol->attrdef_size. */
        ino = ntfs_iget(sb, FILE_AttrDef);
        if (IS_ERR(ino)) {
                if (!IS_ERR(ino))
                        iput(ino);
                goto failed;
        }
        NInoSetSparseDisabled(NTFS_I(ino));
        /* The size of FILE_AttrDef must be above 0 and fit inside 31 bits. */
        i_size = i_size_read(ino);
        if (i_size <= 0 || i_size > 0x7fffffff)
                goto iput_failed;
        vol->attrdef = kvzalloc(i_size, GFP_NOFS);
        if (!vol->attrdef)
                goto iput_failed;
        index = 0;
        max_index = i_size >> PAGE_SHIFT;
        size = PAGE_SIZE;
        while (index < max_index) {
                /* Read the attrdef table and copy it into the linear buffer. */
read_partial_attrdef_page:
                folio = read_mapping_folio(ino->i_mapping, index, NULL);
                if (IS_ERR(folio))
                        goto free_iput_failed;
                addr = kmap_local_folio(folio, 0);
                memcpy((u8 *)vol->attrdef + (index++ << PAGE_SHIFT),
                                addr, size);
                kunmap_local(addr);
                folio_put(folio);
        }
        if (size == PAGE_SIZE) {
                size = i_size & ~PAGE_MASK;
                if (size)
                        goto read_partial_attrdef_page;
        }
        vol->attrdef_size = i_size;
        ntfs_debug("Read %llu bytes from $AttrDef.", i_size);
        iput(ino);
        return true;
free_iput_failed:
        kvfree(vol->attrdef);
        vol->attrdef = NULL;
iput_failed:
        iput(ino);
failed:
        ntfs_error(sb, "Failed to initialize attribute definition table.");
        return false;
}

/*
 * load_and_init_upcase - load the upcase table for an ntfs volume
 * @vol:        ntfs super block describing device whose upcase to load
 *
 * Return 'true' on success or 'false' on error.
 */
static bool load_and_init_upcase(struct ntfs_volume *vol)
{
        loff_t i_size;
        struct super_block *sb = vol->sb;
        struct inode *ino;
        struct folio *folio;
        u8 *addr;
        pgoff_t index, max_index;
        unsigned int size;

        ntfs_debug("Entering.");
        /* Read upcase table and setup vol->upcase and vol->upcase_len. */
        ino = ntfs_iget(sb, FILE_UpCase);
        if (IS_ERR(ino)) {
                if (!IS_ERR(ino))
                        iput(ino);
                goto upcase_failed;
        }
        /*
         * The upcase size must not be above 64k Unicode characters, must not
         * be zero and must be a multiple of sizeof(__le16).
         */
        i_size = i_size_read(ino);
        if (!i_size || i_size & (sizeof(__le16) - 1) ||
                        i_size > 64ULL * 1024 * sizeof(__le16))
                goto iput_upcase_failed;
        vol->upcase = kvzalloc(i_size, GFP_NOFS);
        if (!vol->upcase)
                goto iput_upcase_failed;
        index = 0;
        max_index = i_size >> PAGE_SHIFT;
        size = PAGE_SIZE;
        while (index < max_index) {
                /* Read the upcase table and copy it into the linear buffer. */
read_partial_upcase_page:
                folio = read_mapping_folio(ino->i_mapping, index, NULL);
                if (IS_ERR(folio))
                        goto iput_upcase_failed;
                addr = kmap_local_folio(folio, 0);
                memcpy((char *)vol->upcase + (index++ << PAGE_SHIFT),
                                addr, size);
                kunmap_local(addr);
                folio_put(folio);
        }
        if (size == PAGE_SIZE) {
                size = i_size & ~PAGE_MASK;
                if (size)
                        goto read_partial_upcase_page;
        }
        vol->upcase_len = i_size >> sizeof(unsigned char);
        ntfs_debug("Read %llu bytes from $UpCase (expected %zu bytes).",
                        i_size, 64 * 1024 * sizeof(__le16));
        iput(ino);
        mutex_lock(&ntfs_lock);
        if (!default_upcase) {
                ntfs_debug("Using volume specified $UpCase since default is not present.");
                mutex_unlock(&ntfs_lock);
                return true;
        }
        if (default_upcase_len == vol->upcase_len &&
            !memcmp(vol->upcase, default_upcase,
                    default_upcase_len * sizeof(*default_upcase))) {
                kvfree(vol->upcase);
                vol->upcase = default_upcase;
                ntfs_nr_upcase_users++;
                mutex_unlock(&ntfs_lock);
                ntfs_debug("Volume specified $UpCase matches default. Using default.");
                return true;
        }
        mutex_unlock(&ntfs_lock);
        ntfs_debug("Using volume specified $UpCase since it does not match the default.");
        return true;
iput_upcase_failed:
        iput(ino);
        kvfree(vol->upcase);
        vol->upcase = NULL;
upcase_failed:
        mutex_lock(&ntfs_lock);
        if (default_upcase) {
                vol->upcase = default_upcase;
                vol->upcase_len = default_upcase_len;
                ntfs_nr_upcase_users++;
                mutex_unlock(&ntfs_lock);
                ntfs_error(sb, "Failed to load $UpCase from the volume. Using default.");
                return true;
        }
        mutex_unlock(&ntfs_lock);
        ntfs_error(sb, "Failed to initialize upcase table.");
        return false;
}

/*
 * The lcn and mft bitmap inodes are NTFS-internal inodes with
 * their own special locking rules:
 */
static struct lock_class_key
        lcnbmp_runlist_lock_key, lcnbmp_mrec_lock_key,
        mftbmp_runlist_lock_key, mftbmp_mrec_lock_key;

/*
 * load_system_files - open the system files using normal functions
 * @vol:        ntfs super block describing device whose system files to load
 *
 * Open the system files with normal access functions and complete setting up
 * the ntfs super block @vol.
 *
 * Return 'true' on success or 'false' on error.
 */
static bool load_system_files(struct ntfs_volume *vol)
{
        struct super_block *sb = vol->sb;
        struct mft_record *m;
        struct volume_information *vi;
        struct ntfs_attr_search_ctx *ctx;
        struct restart_page_header *rp;
        int err;

        ntfs_debug("Entering.");
        /* Get mft mirror inode compare the contents of $MFT and $MFTMirr. */
        if (!load_and_init_mft_mirror(vol) || !check_mft_mirror(vol)) {
                /* If a read-write mount, convert it to a read-only mount. */
                if (!sb_rdonly(sb) && vol->on_errors == ON_ERRORS_REMOUNT_RO) {
                        static const char *es1 = "Failed to load $MFTMirr";
                        static const char *es2 = "$MFTMirr does not match $MFT";
                        static const char *es3 = ".  Run ntfsck and/or chkdsk.";

                        sb->s_flags |= SB_RDONLY;
                        ntfs_error(sb, "%s.  Mounting read-only%s",
                                        !vol->mftmirr_ino ? es1 : es2, es3);
                }
                NVolSetErrors(vol);
        }
        /* Get mft bitmap attribute inode. */
        vol->mftbmp_ino = ntfs_attr_iget(vol->mft_ino, AT_BITMAP, NULL, 0);
        if (IS_ERR(vol->mftbmp_ino)) {
                ntfs_error(sb, "Failed to load $MFT/$BITMAP attribute.");
                goto iput_mirr_err_out;
        }
        lockdep_set_class(&NTFS_I(vol->mftbmp_ino)->runlist.lock,
                           &mftbmp_runlist_lock_key);
        lockdep_set_class(&NTFS_I(vol->mftbmp_ino)->mrec_lock,
                           &mftbmp_mrec_lock_key);
        /* Read upcase table and setup @vol->upcase and @vol->upcase_len. */
        if (!load_and_init_upcase(vol))
                goto iput_mftbmp_err_out;
        /*
         * Read attribute definitions table and setup @vol->attrdef and
         * @vol->attrdef_size.
         */
        if (!load_and_init_attrdef(vol))
                goto iput_upcase_err_out;
        /*
         * Get the cluster allocation bitmap inode and verify the size, no
         * need for any locking at this stage as we are already running
         * exclusively as we are mount in progress task.
         */
        vol->lcnbmp_ino = ntfs_iget(sb, FILE_Bitmap);
        if (IS_ERR(vol->lcnbmp_ino)) {
                if (!IS_ERR(vol->lcnbmp_ino))
                        iput(vol->lcnbmp_ino);
                goto bitmap_failed;
        }
        lockdep_set_class(&NTFS_I(vol->lcnbmp_ino)->runlist.lock,
                           &lcnbmp_runlist_lock_key);
        lockdep_set_class(&NTFS_I(vol->lcnbmp_ino)->mrec_lock,
                           &lcnbmp_mrec_lock_key);

        NInoSetSparseDisabled(NTFS_I(vol->lcnbmp_ino));
        if ((vol->nr_clusters + 7) >> 3 > i_size_read(vol->lcnbmp_ino)) {
                iput(vol->lcnbmp_ino);
bitmap_failed:
                ntfs_error(sb, "Failed to load $Bitmap.");
                goto iput_attrdef_err_out;
        }
        /*
         * Get the volume inode and setup our cache of the volume flags and
         * version.
         */
        vol->vol_ino = ntfs_iget(sb, FILE_Volume);
        if (IS_ERR(vol->vol_ino)) {
                if (!IS_ERR(vol->vol_ino))
                        iput(vol->vol_ino);
volume_failed:
                ntfs_error(sb, "Failed to load $Volume.");
                goto iput_lcnbmp_err_out;
        }
        m = map_mft_record(NTFS_I(vol->vol_ino));
        if (IS_ERR(m)) {
iput_volume_failed:
                iput(vol->vol_ino);
                goto volume_failed;
        }

        ctx = ntfs_attr_get_search_ctx(NTFS_I(vol->vol_ino), m);
        if (!ctx) {
                ntfs_error(sb, "Failed to get attribute search context.");
                goto get_ctx_vol_failed;
        }

        if (!ntfs_attr_lookup(AT_VOLUME_NAME, NULL, 0, 0, 0, NULL, 0, ctx) &&
            !ctx->attr->non_resident &&
            !(ctx->attr->flags & (ATTR_IS_SPARSE | ATTR_IS_COMPRESSED)) &&
            le32_to_cpu(ctx->attr->data.resident.value_length) > 0) {
                err = ntfs_ucstonls(vol, (__le16 *)((u8 *)ctx->attr +
                                    le16_to_cpu(ctx->attr->data.resident.value_offset)),
                                    le32_to_cpu(ctx->attr->data.resident.value_length) / 2,
                                    &vol->volume_label, NTFS_MAX_LABEL_LEN);
                if (err < 0)
                        vol->volume_label = NULL;
        }

        ntfs_attr_reinit_search_ctx(ctx);
        if (ntfs_attr_lookup(AT_VOLUME_INFORMATION, NULL, 0, 0, 0, NULL, 0,
                        ctx) || ctx->attr->non_resident || ctx->attr->flags) {
                ntfs_attr_put_search_ctx(ctx);
get_ctx_vol_failed:
                unmap_mft_record(NTFS_I(vol->vol_ino));
                goto iput_volume_failed;
        }
        vi = (struct volume_information *)((char *)ctx->attr +
                        le16_to_cpu(ctx->attr->data.resident.value_offset));
        /* Copy the volume flags and version to the struct ntfs_volume structure. */
        vol->vol_flags = vi->flags;
        vol->major_ver = vi->major_ver;
        vol->minor_ver = vi->minor_ver;
        ntfs_attr_put_search_ctx(ctx);
        unmap_mft_record(NTFS_I(vol->vol_ino));
        pr_info("volume version %i.%i, dev %s, cluster size %d\n",
                vol->major_ver, vol->minor_ver, sb->s_id, vol->cluster_size);

        /* Make sure that no unsupported volume flags are set. */
        if (vol->vol_flags & VOLUME_MUST_MOUNT_RO_MASK) {
                static const char *es1a = "Volume is dirty";
                static const char *es1b = "Volume has been modified by chkdsk";
                static const char *es1c = "Volume has unsupported flags set";
                static const char *es2a = ".  Run chkdsk and mount in Windows.";
                static const char *es2b = ".  Mount in Windows.";
                const char *es1, *es2;

                es2 = es2a;
                if (vol->vol_flags & VOLUME_IS_DIRTY)
                        es1 = es1a;
                else if (vol->vol_flags & VOLUME_MODIFIED_BY_CHKDSK) {
                        es1 = es1b;
                        es2 = es2b;
                } else {
                        es1 = es1c;
                        ntfs_warning(sb, "Unsupported volume flags 0x%x encountered.",
                                        (unsigned int)le16_to_cpu(vol->vol_flags));
                }
                /* If a read-write mount, convert it to a read-only mount. */
                if (!sb_rdonly(sb) && vol->on_errors == ON_ERRORS_REMOUNT_RO) {
                        sb->s_flags |= SB_RDONLY;
                        ntfs_error(sb, "%s.  Mounting read-only%s", es1, es2);
                }
                /*
                 * Do not set NVolErrors() because ntfs_remount() re-checks the
                 * flags which we need to do in case any flags have changed.
                 */
        }
        /*
         * Get the inode for the logfile, check it and determine if the volume
         * was shutdown cleanly.
         */
        rp = NULL;
        err = load_and_check_logfile(vol, &rp);
        if (err) {
                /* If a read-write mount, convert it to a read-only mount. */
                if (!sb_rdonly(sb) && vol->on_errors == ON_ERRORS_REMOUNT_RO) {
                        sb->s_flags |= SB_RDONLY;
                        ntfs_error(sb, "Failed to load LogFile. Mounting read-only.");
                }
                NVolSetErrors(vol);
        }

        kvfree(rp);
        /* Get the root directory inode so we can do path lookups. */
        vol->root_ino = ntfs_iget(sb, FILE_root);
        if (IS_ERR(vol->root_ino)) {
                if (!IS_ERR(vol->root_ino))
                        iput(vol->root_ino);
                ntfs_error(sb, "Failed to load root directory.");
                goto iput_logfile_err_out;
        }
        /*
         * Check if Windows is suspended to disk on the target volume.  If it
         * is hibernated, we must not write *anything* to the disk so set
         * NVolErrors() without setting the dirty volume flag and mount
         * read-only.  This will prevent read-write remounting and it will also
         * prevent all writes.
         */
        err = check_windows_hibernation_status(vol);
        if (unlikely(err)) {
                static const char *es1a = "Failed to determine if Windows is hibernated";
                static const char *es1b = "Windows is hibernated";
                static const char *es2 = ".  Run chkdsk.";
                const char *es1;

                es1 = err < 0 ? es1a : es1b;
                /* If a read-write mount, convert it to a read-only mount. */
                if (!sb_rdonly(sb) && vol->on_errors == ON_ERRORS_REMOUNT_RO) {
                        sb->s_flags |= SB_RDONLY;
                        ntfs_error(sb, "%s.  Mounting read-only%s", es1, es2);
                }
                NVolSetErrors(vol);
        }

        /* If (still) a read-write mount, empty the logfile. */
        if (!sb_rdonly(sb) &&
            vol->logfile_ino && !ntfs_empty_logfile(vol->logfile_ino) &&
            vol->on_errors == ON_ERRORS_REMOUNT_RO) {
                static const char *es1 = "Failed to empty LogFile";
                static const char *es2 = ".  Mount in Windows.";

                /* Convert to a read-only mount. */
                ntfs_error(sb, "%s.  Mounting read-only%s", es1, es2);
                sb->s_flags |= SB_RDONLY;
                NVolSetErrors(vol);
        }
        /* If on NTFS versions before 3.0, we are done. */
        if (unlikely(vol->major_ver < 3))
                return true;
        /* NTFS 3.0+ specific initialization. */
        /* Get the security descriptors inode. */
        vol->secure_ino = ntfs_iget(sb, FILE_Secure);
        if (IS_ERR(vol->secure_ino)) {
                if (!IS_ERR(vol->secure_ino))
                        iput(vol->secure_ino);
                ntfs_error(sb, "Failed to load $Secure.");
                goto iput_root_err_out;
        }
        /* Get the extended system files' directory inode. */
        vol->extend_ino = ntfs_iget(sb, FILE_Extend);
        if (IS_ERR(vol->extend_ino) ||
            !S_ISDIR(vol->extend_ino->i_mode)) {
                if (!IS_ERR(vol->extend_ino))
                        iput(vol->extend_ino);
                ntfs_error(sb, "Failed to load $Extend.");
                goto iput_sec_err_out;
        }
        return true;

iput_sec_err_out:
        iput(vol->secure_ino);
iput_root_err_out:
        iput(vol->root_ino);
iput_logfile_err_out:
        if (vol->logfile_ino)
                iput(vol->logfile_ino);
        iput(vol->vol_ino);
iput_lcnbmp_err_out:
        iput(vol->lcnbmp_ino);
iput_attrdef_err_out:
        vol->attrdef_size = 0;
        if (vol->attrdef) {
                kvfree(vol->attrdef);
                vol->attrdef = NULL;
        }
iput_upcase_err_out:
        vol->upcase_len = 0;
        mutex_lock(&ntfs_lock);
        if (vol->upcase && vol->upcase == default_upcase) {
                ntfs_nr_upcase_users--;
                vol->upcase = NULL;
        }
        mutex_unlock(&ntfs_lock);
        if (vol->upcase) {
                kvfree(vol->upcase);
                vol->upcase = NULL;
        }
iput_mftbmp_err_out:
        iput(vol->mftbmp_ino);
iput_mirr_err_out:
        iput(vol->mftmirr_ino);
        return false;
}

static void ntfs_volume_free(struct ntfs_volume *vol)
{
        /* Throw away the table of attribute definitions. */
        vol->attrdef_size = 0;
        if (vol->attrdef) {
                kvfree(vol->attrdef);
                vol->attrdef = NULL;
        }
        vol->upcase_len = 0;
        /*
         * Destroy the global default upcase table if necessary.  Also decrease
         * the number of upcase users if we are a user.
         */
        mutex_lock(&ntfs_lock);
        if (vol->upcase && vol->upcase == default_upcase) {
                ntfs_nr_upcase_users--;
                vol->upcase = NULL;
        }

        if (!ntfs_nr_upcase_users) {
                kvfree(default_upcase);
                default_upcase = NULL;
        }

        free_compression_buffers();

        mutex_unlock(&ntfs_lock);
        if (vol->upcase) {
                kvfree(vol->upcase);
                vol->upcase = NULL;
        }

        unload_nls(vol->nls_map);

        kvfree(vol->lcn_empty_bits_per_page);
        kfree(vol->volume_label);
        kfree(vol);
}

/*
 * ntfs_put_super - called by the vfs to unmount a volume
 * @sb:         vfs superblock of volume to unmount
 */
static void ntfs_put_super(struct super_block *sb)
{
        struct ntfs_volume *vol = NTFS_SB(sb);

        pr_info("Entering %s, dev %s\n", __func__, sb->s_id);

        cancel_work_sync(&vol->precalc_work);

        /*
         * Commit all inodes while they are still open in case some of them
         * cause others to be dirtied.
         */
        ntfs_commit_inode(vol->vol_ino);

        /* NTFS 3.0+ specific. */
        if (vol->major_ver >= 3) {
                if (vol->extend_ino)
                        ntfs_commit_inode(vol->extend_ino);
                if (vol->secure_ino)
                        ntfs_commit_inode(vol->secure_ino);
        }

        ntfs_commit_inode(vol->root_ino);

        ntfs_commit_inode(vol->lcnbmp_ino);

        /*
         * the GFP_NOFS scope is not needed because ntfs_commit_inode
         * does nothing
         */
        ntfs_commit_inode(vol->mftbmp_ino);

        if (vol->logfile_ino)
                ntfs_commit_inode(vol->logfile_ino);

        if (vol->mftmirr_ino)
                ntfs_commit_inode(vol->mftmirr_ino);
        ntfs_commit_inode(vol->mft_ino);

        /*
         * If a read-write mount and no volume errors have occurred, mark the
         * volume clean.  Also, re-commit all affected inodes.
         */
        if (!sb_rdonly(sb)) {
                if (!NVolErrors(vol)) {
                        if (ntfs_clear_volume_flags(vol, VOLUME_IS_DIRTY))
                                ntfs_warning(sb,
                                        "Failed to clear dirty bit in volume information flags.  Run chkdsk.");
                        ntfs_commit_inode(vol->vol_ino);
                        ntfs_commit_inode(vol->root_ino);
                        if (vol->mftmirr_ino)
                                ntfs_commit_inode(vol->mftmirr_ino);
                        ntfs_commit_inode(vol->mft_ino);
                } else {
                        ntfs_warning(sb,
                                "Volume has errors.  Leaving volume marked dirty.  Run chkdsk.");
                }
        }

        iput(vol->vol_ino);
        vol->vol_ino = NULL;

        /* NTFS 3.0+ specific clean up. */
        if (vol->major_ver >= 3) {
                if (vol->extend_ino) {
                        iput(vol->extend_ino);
                        vol->extend_ino = NULL;
                }
                if (vol->secure_ino) {
                        iput(vol->secure_ino);
                        vol->secure_ino = NULL;
                }
        }

        iput(vol->root_ino);
        vol->root_ino = NULL;

        iput(vol->lcnbmp_ino);
        vol->lcnbmp_ino = NULL;

        iput(vol->mftbmp_ino);
        vol->mftbmp_ino = NULL;

        if (vol->logfile_ino) {
                iput(vol->logfile_ino);
                vol->logfile_ino = NULL;
        }
        if (vol->mftmirr_ino) {
                /* Re-commit the mft mirror and mft just in case. */
                ntfs_commit_inode(vol->mftmirr_ino);
                ntfs_commit_inode(vol->mft_ino);
                iput(vol->mftmirr_ino);
                vol->mftmirr_ino = NULL;
        }
        /*
         * We should have no dirty inodes left, due to
         * mft.c::ntfs_mft_writepage() cleaning all the dirty pages as
         * the underlying mft records are written out and cleaned.
         */
        ntfs_commit_inode(vol->mft_ino);
        write_inode_now(vol->mft_ino, 1);

        iput(vol->mft_ino);
        vol->mft_ino = NULL;
        blkdev_issue_flush(sb->s_bdev);

        ntfs_volume_free(vol);
}

int ntfs_force_shutdown(struct super_block *sb, u32 flags)
{
        struct ntfs_volume *vol = NTFS_SB(sb);
        int ret;

        if (NVolShutdown(vol))
                return 0;

        switch (flags) {
        case FS_SHUTDOWN_FLAGS_DEFAULT:
        case FS_SHUTDOWN_FLAGS_LOGFLUSH:
                ret = bdev_freeze(sb->s_bdev);
                if (ret)
                        return ret;
                bdev_thaw(sb->s_bdev);
                NVolSetShutdown(vol);
                break;
        case FS_SHUTDOWN_FLAGS_NOLOGFLUSH:
                NVolSetShutdown(vol);
                break;
        default:
                return -EINVAL;
        }

        return 0;
}

static void ntfs_shutdown(struct super_block *sb)
{
        ntfs_force_shutdown(sb, FS_SHUTDOWN_FLAGS_NOLOGFLUSH);

}

static int ntfs_sync_fs(struct super_block *sb, int wait)
{
        struct ntfs_volume *vol = NTFS_SB(sb);
        int err = 0;

        if (NVolShutdown(vol))
                return -EIO;

        if (!wait)
                return 0;

        /* If there are some dirty buffers in the bdev inode */
        if (ntfs_clear_volume_flags(vol, VOLUME_IS_DIRTY)) {
                ntfs_warning(sb, "Failed to clear dirty bit in volume information flags.  Run chkdsk.");
                err = -EIO;
        }
        sync_inodes_sb(sb);
        sync_blockdev(sb->s_bdev);
        blkdev_issue_flush(sb->s_bdev);
        return err;
}

/*
 * get_nr_free_clusters - return the number of free clusters on a volume
 * @vol:        ntfs volume for which to obtain free cluster count
 *
 * Calculate the number of free clusters on the mounted NTFS volume @vol. We
 * actually calculate the number of clusters in use instead because this
 * allows us to not care about partial pages as these will be just zero filled
 * and hence not be counted as allocated clusters.
 *
 * The only particularity is that clusters beyond the end of the logical ntfs
 * volume will be marked as allocated to prevent errors which means we have to
 * discount those at the end. This is important as the cluster bitmap always
 * has a size in multiples of 8 bytes, i.e. up to 63 clusters could be outside
 * the logical volume and marked in use when they are not as they do not exist.
 *
 * If any pages cannot be read we assume all clusters in the erroring pages are
 * in use. This means we return an underestimate on errors which is better than
 * an overestimate.
 */
s64 get_nr_free_clusters(struct ntfs_volume *vol)
{
        s64 nr_free = vol->nr_clusters;
        u32 nr_used;
        struct address_space *mapping = vol->lcnbmp_ino->i_mapping;
        struct folio *folio;
        pgoff_t index, max_index;
        struct file_ra_state ra = { 0 };

        ntfs_debug("Entering.");
        /* Serialize accesses to the cluster bitmap. */

        if (NVolFreeClusterKnown(vol))
                return atomic64_read(&vol->free_clusters);

        file_ra_state_init(&ra, mapping);

        /*
         * Convert the number of bits into bytes rounded up, then convert into
         * multiples of PAGE_SIZE, rounding up so that if we have one
         * full and one partial page max_index = 2.
         */
        max_index = (((vol->nr_clusters + 7) >> 3) + PAGE_SIZE - 1) >>
                        PAGE_SHIFT;
        /* Use multiples of 4 bytes, thus max_size is PAGE_SIZE / 4. */
        ntfs_debug("Reading $Bitmap, max_index = 0x%lx, max_size = 0x%lx.",
                        max_index, PAGE_SIZE / 4);
        for (index = 0; index < max_index; index++) {
                unsigned long *kaddr;

                /*
                 * Get folio from page cache, getting it from backing store
                 * if necessary, and increment the use count.
                 */
                folio = ntfs_get_locked_folio(mapping, index, max_index, &ra);

                /* Ignore pages which errored synchronously. */
                if (IS_ERR(folio)) {
                        ntfs_debug("Skipping page (index 0x%lx).", index);
                        nr_free -= PAGE_SIZE * 8;
                        vol->lcn_empty_bits_per_page[index] = 0;
                        continue;
                }

                kaddr = kmap_local_folio(folio, 0);
                /*
                 * Subtract the number of set bits. If this
                 * is the last page and it is partial we don't really care as
                 * it just means we do a little extra work but it won't affect
                 * the result as all out of range bytes are set to zero by
                 * ntfs_readpage().
                 */
                nr_used = bitmap_weight(kaddr, PAGE_SIZE * BITS_PER_BYTE);
                nr_free -= nr_used;
                vol->lcn_empty_bits_per_page[index] = PAGE_SIZE * BITS_PER_BYTE - nr_used;
                kunmap_local(kaddr);
                folio_unlock(folio);
                folio_put(folio);
        }
        ntfs_debug("Finished reading $Bitmap, last index = 0x%lx.", index - 1);
        /*
         * Fixup for eventual bits outside logical ntfs volume (see function
         * description above).
         */
        if (vol->nr_clusters & 63)
                nr_free += 64 - (vol->nr_clusters & 63);

        /* If errors occurred we may well have gone below zero, fix this. */
        if (nr_free < 0)
                nr_free = 0;
        else
                atomic64_set(&vol->free_clusters, nr_free);

        NVolSetFreeClusterKnown(vol);
        wake_up_all(&vol->free_waitq);
        ntfs_debug("Exiting.");
        return nr_free;
}

/*
 * @nr_clusters is the number of clusters requested for allocation.
 *
 * Return the number of clusters available for allocation within
 * the range of @nr_clusters, which is counts that considered
 * for delayed allocation.
 */
s64 ntfs_available_clusters_count(struct ntfs_volume *vol, s64 nr_clusters)
{
        s64 free_clusters;

        /* wait event */
        if (!NVolFreeClusterKnown(vol))
                wait_event(vol->free_waitq, NVolFreeClusterKnown(vol));

        free_clusters = atomic64_read(&vol->free_clusters) -
                atomic64_read(&vol->dirty_clusters);
        if (free_clusters <= 0)
                return -ENOSPC;
        else if (free_clusters < nr_clusters)
                nr_clusters = free_clusters;

        return nr_clusters;
}

/*
 * __get_nr_free_mft_records - return the number of free inodes on a volume
 * @vol:        ntfs volume for which to obtain free inode count
 * @nr_free:    number of mft records in filesystem
 * @max_index:  maximum number of pages containing set bits
 *
 * Calculate the number of free mft records (inodes) on the mounted NTFS
 * volume @vol. We actually calculate the number of mft records in use instead
 * because this allows us to not care about partial pages as these will be just
 * zero filled and hence not be counted as allocated mft record.
 *
 * If any pages cannot be read we assume all mft records in the erroring pages
 * are in use. This means we return an underestimate on errors which is better
 * than an overestimate.
 *
 * NOTE: Caller must hold mftbmp_lock rw_semaphore for reading or writing.
 */
static unsigned long __get_nr_free_mft_records(struct ntfs_volume *vol,
                s64 nr_free, const pgoff_t max_index)
{
        struct address_space *mapping = vol->mftbmp_ino->i_mapping;
        struct folio *folio;
        pgoff_t index;
        struct file_ra_state ra = { 0 };

        ntfs_debug("Entering.");

        file_ra_state_init(&ra, mapping);

        /* Use multiples of 4 bytes, thus max_size is PAGE_SIZE / 4. */
        ntfs_debug("Reading $MFT/$BITMAP, max_index = 0x%lx, max_size = 0x%lx.",
                        max_index, PAGE_SIZE / 4);
        for (index = 0; index < max_index; index++) {
                unsigned long *kaddr;

                /*
                 * Get folio from page cache, getting it from backing store
                 * if necessary, and increment the use count.
                 */
                folio = ntfs_get_locked_folio(mapping, index, max_index, &ra);

                /* Ignore pages which errored synchronously. */
                if (IS_ERR(folio)) {
                        ntfs_debug("read_mapping_page() error. Skipping page (index 0x%lx).",
                                        index);
                        nr_free -= PAGE_SIZE * 8;
                        continue;
                }

                kaddr = kmap_local_folio(folio, 0);
                /*
                 * Subtract the number of set bits. If this
                 * is the last page and it is partial we don't really care as
                 * it just means we do a little extra work but it won't affect
                 * the result as all out of range bytes are set to zero by
                 * ntfs_readpage().
                 */
                nr_free -= bitmap_weight(kaddr,
                                        PAGE_SIZE * BITS_PER_BYTE);
                kunmap_local(kaddr);
                folio_unlock(folio);
                folio_put(folio);
        }
        ntfs_debug("Finished reading $MFT/$BITMAP, last index = 0x%lx.",
                        index - 1);
        /* If errors occurred we may well have gone below zero, fix this. */
        if (nr_free < 0)
                nr_free = 0;
        else
                atomic64_set(&vol->free_mft_records, nr_free);

        ntfs_debug("Exiting.");
        return nr_free;
}

/*
 * ntfs_statfs - return information about mounted NTFS volume
 * @dentry:     dentry from mounted volume
 * @sfs:        statfs structure in which to return the information
 *
 * Return information about the mounted NTFS volume @dentry in the statfs structure
 * pointed to by @sfs (this is initialized with zeros before ntfs_statfs is
 * called). We interpret the values to be correct of the moment in time at
 * which we are called. Most values are variable otherwise and this isn't just
 * the free values but the totals as well. For example we can increase the
 * total number of file nodes if we run out and we can keep doing this until
 * there is no more space on the volume left at all.
 *
 * Called from vfs_statfs which is used to handle the statfs, fstatfs, and
 * ustat system calls.
 *
 * Return 0 on success or -errno on error.
 */
static int ntfs_statfs(struct dentry *dentry, struct kstatfs *sfs)
{
        struct super_block *sb = dentry->d_sb;
        s64 size;
        struct ntfs_volume *vol = NTFS_SB(sb);
        struct ntfs_inode *mft_ni = NTFS_I(vol->mft_ino);
        unsigned long flags;

        ntfs_debug("Entering.");
        /* Type of filesystem. */
        sfs->f_type   = NTFS_SB_MAGIC;
        /* Optimal transfer block size. */
        sfs->f_bsize = vol->cluster_size;
        /* Fundamental file system block size, used as the unit. */
        sfs->f_frsize = vol->cluster_size;

        /*
         * Total data blocks in filesystem in units of f_bsize and since
         * inodes are also stored in data blocs ($MFT is a file) this is just
         * the total clusters.
         */
        sfs->f_blocks = vol->nr_clusters;

        /* wait event */
        if (!NVolFreeClusterKnown(vol))
                wait_event(vol->free_waitq, NVolFreeClusterKnown(vol));

        /* Free data blocks in filesystem in units of f_bsize. */
        size = atomic64_read(&vol->free_clusters) -
                atomic64_read(&vol->dirty_clusters);
        if (size < 0LL)
                size = 0LL;

        /* Free blocks avail to non-superuser, same as above on NTFS. */
        sfs->f_bavail = sfs->f_bfree = size;

        /* Number of inodes in filesystem (at this point in time). */
        read_lock_irqsave(&mft_ni->size_lock, flags);
        sfs->f_files = i_size_read(vol->mft_ino) >> vol->mft_record_size_bits;
        read_unlock_irqrestore(&mft_ni->size_lock, flags);

        /* Free inodes in fs (based on current total count). */
        sfs->f_ffree = atomic64_read(&vol->free_mft_records);

        /*
         * File system id. This is extremely *nix flavour dependent and even
         * within Linux itself all fs do their own thing. I interpret this to
         * mean a unique id associated with the mounted fs and not the id
         * associated with the filesystem driver, the latter is already given
         * by the filesystem type in sfs->f_type. Thus we use the 64-bit
         * volume serial number splitting it into two 32-bit parts. We enter
         * the least significant 32-bits in f_fsid[0] and the most significant
         * 32-bits in f_fsid[1].
         */
        sfs->f_fsid = u64_to_fsid(vol->serial_no);
        /* Maximum length of filenames. */
        sfs->f_namelen     = NTFS_MAX_NAME_LEN;

        return 0;
}

static int ntfs_write_inode(struct inode *vi, struct writeback_control *wbc)
{
        return __ntfs_write_inode(vi, wbc->sync_mode == WB_SYNC_ALL);
}

/*
 * The complete super operations.
 */
static const struct super_operations ntfs_sops = {
        .alloc_inode    = ntfs_alloc_big_inode,   /* VFS: Allocate new inode. */
        .free_inode     = ntfs_free_big_inode, /* VFS: Deallocate inode. */
        .drop_inode     = ntfs_drop_big_inode,
        .write_inode    = ntfs_write_inode,     /* VFS: Write dirty inode to disk. */
        .put_super      = ntfs_put_super,       /* Syscall: umount. */
        .shutdown       = ntfs_shutdown,
        .sync_fs        = ntfs_sync_fs,         /* Syscall: sync. */
        .statfs         = ntfs_statfs,          /* Syscall: statfs */
        .evict_inode    = ntfs_evict_big_inode,
        .show_options   = ntfs_show_options,    /* Show mount options in proc. */
};

static void precalc_free_clusters(struct work_struct *work)
{
        struct ntfs_volume *vol = container_of(work, struct ntfs_volume, precalc_work);
        s64 nr_free;

        nr_free = get_nr_free_clusters(vol);

        ntfs_debug("pre-calculate free clusters(%lld) using workqueue",
                        nr_free);
}

static struct lock_class_key ntfs_mft_inval_lock_key;

/*
 * ntfs_fill_super - mount an ntfs filesystem
 * @sb: super block of the device to mount
 * @fc: filesystem context containing mount options
 *
 * ntfs_fill_super() is called by the VFS to mount the device described by @sb
 * with the mount otions in @data with the NTFS filesystem.
 *
 * If @silent is true, remain silent even if errors are detected. This is used
 * during bootup, when the kernel tries to mount the root filesystem with all
 * registered filesystems one after the other until one succeeds. This implies
 * that all filesystems except the correct one will quite correctly and
 * expectedly return an error, but nobody wants to see error messages when in
 * fact this is what is supposed to happen.
 */
static int ntfs_fill_super(struct super_block *sb, struct fs_context *fc)
{
        char *boot;
        struct inode *tmp_ino;
        int blocksize, result;
        pgoff_t lcn_bit_pages;
        struct ntfs_volume *vol = NTFS_SB(sb);
        int silent = fc->sb_flags & SB_SILENT;

        vol->sb = sb;

        /*
         * We do a pretty difficult piece of bootstrap by reading the
         * MFT (and other metadata) from disk into memory. We'll only
         * release this metadata during umount, so the locking patterns
         * observed during bootstrap do not count. So turn off the
         * observation of locking patterns (strictly for this context
         * only) while mounting NTFS. [The validator is still active
         * otherwise, even for this context: it will for example record
         * lock class registrations.]
         */
        lockdep_off();
        ntfs_debug("Entering.");

        if (vol->nls_map && !strcmp(vol->nls_map->charset, "utf8"))
                vol->nls_utf8 = true;
        if (NVolDisableSparse(vol))
                vol->preallocated_size = 0;

        if (NVolDiscard(vol) && !bdev_max_discard_sectors(sb->s_bdev)) {
                ntfs_warning(
                        sb,
                        "Discard requested but device does not support discard.  Discard disabled.");
                NVolClearDiscard(vol);
        }

        /* We support sector sizes up to the PAGE_SIZE. */
        if (bdev_logical_block_size(sb->s_bdev) > PAGE_SIZE) {
                if (!silent)
                        ntfs_error(sb,
                                "Device has unsupported sector size (%i).  The maximum supported sector size on this architecture is %lu bytes.",
                                bdev_logical_block_size(sb->s_bdev),
                                PAGE_SIZE);
                goto err_out_now;
        }

        /*
         * Setup the device access block size to NTFS_BLOCK_SIZE or the hard
         * sector size, whichever is bigger.
         */
        blocksize = sb_min_blocksize(sb, NTFS_BLOCK_SIZE);
        if (blocksize < NTFS_BLOCK_SIZE) {
                if (!silent)
                        ntfs_error(sb, "Unable to set device block size.");
                goto err_out_now;
        }

        ntfs_debug("Set device block size to %i bytes (block size bits %i).",
                        blocksize, sb->s_blocksize_bits);
        /* Determine the size of the device in units of block_size bytes. */
        if (!bdev_nr_bytes(sb->s_bdev)) {
                if (!silent)
                        ntfs_error(sb, "Unable to determine device size.");
                goto err_out_now;
        }
        vol->nr_blocks = bdev_nr_bytes(sb->s_bdev) >>
                        sb->s_blocksize_bits;
        /* Read the boot sector and return unlocked buffer head to it. */
        boot = read_ntfs_boot_sector(sb, silent);
        if (!boot) {
                if (!silent)
                        ntfs_error(sb, "Not an NTFS volume.");
                goto err_out_now;
        }
        /*
         * Extract the data from the boot sector and setup the ntfs volume
         * using it.
         */
        result = parse_ntfs_boot_sector(vol, (struct ntfs_boot_sector *)boot);
        kfree(boot);
        if (!result) {
                if (!silent)
                        ntfs_error(sb, "Unsupported NTFS filesystem.");
                goto err_out_now;
        }

        if (vol->sector_size > blocksize) {
                blocksize = sb_set_blocksize(sb, vol->sector_size);
                if (blocksize != vol->sector_size) {
                        if (!silent)
                                ntfs_error(sb,
                                           "Unable to set device block size to sector size (%i).",
                                           vol->sector_size);
                        goto err_out_now;
                }
                vol->nr_blocks = bdev_nr_bytes(sb->s_bdev) >>
                                sb->s_blocksize_bits;
                ntfs_debug("Changed device block size to %i bytes (block size bits %i) to match volume sector size.",
                                blocksize, sb->s_blocksize_bits);
        }
        /* Initialize the cluster and mft allocators. */
        ntfs_setup_allocators(vol);
        /* Setup remaining fields in the super block. */
        sb->s_magic = NTFS_SB_MAGIC;
        /*
         * Ntfs allows 63 bits for the file size, i.e. correct would be:
         *      sb->s_maxbytes = ~0ULL >> 1;
         * But the kernel uses a long as the page cache page index which on
         * 32-bit architectures is only 32-bits. MAX_LFS_FILESIZE is kernel
         * defined to the maximum the page cache page index can cope with
         * without overflowing the index or to 2^63 - 1, whichever is smaller.
         */
        sb->s_maxbytes = MAX_LFS_FILESIZE;
        /* Ntfs measures time in 100ns intervals. */
        sb->s_time_gran = 100;

        sb->s_xattr = ntfs_xattr_handlers;
        /*
         * Now load the metadata required for the page cache and our address
         * space operations to function. We do this by setting up a specialised
         * read_inode method and then just calling the normal iget() to obtain
         * the inode for $MFT which is sufficient to allow our normal inode
         * operations and associated address space operations to function.
         */
        sb->s_op = &ntfs_sops;
        tmp_ino = new_inode(sb);
        if (!tmp_ino) {
                if (!silent)
                        ntfs_error(sb, "Failed to load essential metadata.");
                goto err_out_now;
        }

        tmp_ino->i_ino = FILE_MFT;
        insert_inode_hash(tmp_ino);
        if (ntfs_read_inode_mount(tmp_ino) < 0) {
                if (!silent)
                        ntfs_error(sb, "Failed to load essential metadata.");
                goto iput_tmp_ino_err_out_now;
        }
        lockdep_set_class(&tmp_ino->i_mapping->invalidate_lock,
                          &ntfs_mft_inval_lock_key);

        mutex_lock(&ntfs_lock);

        /*
         * Generate the global default upcase table if necessary.  Also
         * temporarily increment the number of upcase users to avoid race
         * conditions with concurrent (u)mounts.
         */
        if (!default_upcase)
                default_upcase = generate_default_upcase();
        ntfs_nr_upcase_users++;
        mutex_unlock(&ntfs_lock);

        lcn_bit_pages = (((vol->nr_clusters + 7) >> 3) + PAGE_SIZE - 1) >> PAGE_SHIFT;
        vol->lcn_empty_bits_per_page = kvmalloc_array(lcn_bit_pages, sizeof(unsigned int),
                                                      GFP_KERNEL);
        if (!vol->lcn_empty_bits_per_page) {
                ntfs_error(sb,
                           "Unable to allocate pages for storing LCN empty bit counts\n");
                goto unl_upcase_iput_tmp_ino_err_out_now;
        }

        /*
         * From now on, ignore @silent parameter. If we fail below this line,
         * it will be due to a corrupt fs or a system error, so we report it.
         */
        /*
         * Open the system files with normal access functions and complete
         * setting up the ntfs super block.
         */
        if (!load_system_files(vol)) {
                ntfs_error(sb, "Failed to load system files.");
                goto unl_upcase_iput_tmp_ino_err_out_now;
        }

        /* We grab a reference, simulating an ntfs_iget(). */
        ihold(vol->root_ino);
        sb->s_root = d_make_root(vol->root_ino);
        if (sb->s_root) {
                s64 nr_records;

                ntfs_debug("Exiting, status successful.");

                /* Release the default upcase if it has no users. */
                mutex_lock(&ntfs_lock);
                if (!--ntfs_nr_upcase_users && default_upcase) {
                        kvfree(default_upcase);
                        default_upcase = NULL;
                }
                mutex_unlock(&ntfs_lock);
                sb->s_export_op = &ntfs_export_ops;
                lockdep_on();

                nr_records = __get_nr_free_mft_records(vol,
                                i_size_read(vol->mft_ino) >> vol->mft_record_size_bits,
                                ((((NTFS_I(vol->mft_ino)->initialized_size >>
                                    vol->mft_record_size_bits) +
                                   7) >> 3) + PAGE_SIZE - 1) >> PAGE_SHIFT);
                ntfs_debug("Free mft records(%lld)", nr_records);

                init_waitqueue_head(&vol->free_waitq);
                INIT_WORK(&vol->precalc_work, precalc_free_clusters);
                queue_work(ntfs_wq, &vol->precalc_work);
                return 0;
        }
        ntfs_error(sb, "Failed to allocate root directory.");
        /* Clean up after the successful load_system_files() call from above. */
        iput(vol->vol_ino);
        vol->vol_ino = NULL;
        /* NTFS 3.0+ specific clean up. */
        if (vol->major_ver >= 3) {
                if (vol->extend_ino) {
                        iput(vol->extend_ino);
                        vol->extend_ino = NULL;
                }
                if (vol->secure_ino) {
                        iput(vol->secure_ino);
                        vol->secure_ino = NULL;
                }
        }
        iput(vol->root_ino);
        vol->root_ino = NULL;
        iput(vol->lcnbmp_ino);
        vol->lcnbmp_ino = NULL;
        iput(vol->mftbmp_ino);
        vol->mftbmp_ino = NULL;
        if (vol->logfile_ino) {
                iput(vol->logfile_ino);
                vol->logfile_ino = NULL;
        }
        if (vol->mftmirr_ino) {
                iput(vol->mftmirr_ino);
                vol->mftmirr_ino = NULL;
        }
        /* Throw away the table of attribute definitions. */
        vol->attrdef_size = 0;
        if (vol->attrdef) {
                kvfree(vol->attrdef);
                vol->attrdef = NULL;
        }
        vol->upcase_len = 0;
        mutex_lock(&ntfs_lock);
        if (vol->upcase && vol->upcase == default_upcase) {
                ntfs_nr_upcase_users--;
                vol->upcase = NULL;
        }
        mutex_unlock(&ntfs_lock);
        if (vol->upcase) {
                kvfree(vol->upcase);
                vol->upcase = NULL;
        }
        if (vol->nls_map) {
                unload_nls(vol->nls_map);
                vol->nls_map = NULL;
        }
        /* Error exit code path. */
unl_upcase_iput_tmp_ino_err_out_now:
        /*
         * Decrease the number of upcase users and destroy the global default
         * upcase table if necessary.
         */
        mutex_lock(&ntfs_lock);
        if (!--ntfs_nr_upcase_users && default_upcase) {
                kvfree(default_upcase);
                default_upcase = NULL;
        }

        mutex_unlock(&ntfs_lock);
iput_tmp_ino_err_out_now:
        iput(tmp_ino);
        if (vol->mft_ino && vol->mft_ino != tmp_ino)
                iput(vol->mft_ino);
        vol->mft_ino = NULL;
        /* Errors at this stage are irrelevant. */
err_out_now:
        sb->s_fs_info = NULL;
        kvfree(vol->lcn_empty_bits_per_page);
        kfree(vol->volume_label);
        unload_nls(vol->nls_map);
        kfree(vol);
        ntfs_debug("Failed, returning -EINVAL.");
        lockdep_on();
        return -EINVAL;
}

/*
 * This is a slab cache to optimize allocations and deallocations of Unicode
 * strings of the maximum length allowed by NTFS, which is NTFS_MAX_NAME_LEN
 * (255) Unicode characters + a terminating NULL Unicode character.
 */
struct kmem_cache *ntfs_name_cache;

/* Slab caches for efficient allocation/deallocation of inodes. */
struct kmem_cache *ntfs_inode_cache;
struct kmem_cache *ntfs_big_inode_cache;

/* Init once constructor for the inode slab cache. */
static void ntfs_big_inode_init_once(void *foo)
{
        struct ntfs_inode *ni = foo;

        inode_init_once(VFS_I(ni));
}

/*
 * Slab caches to optimize allocations and deallocations of attribute search
 * contexts and index contexts, respectively.
 */
struct kmem_cache *ntfs_attr_ctx_cache;
struct kmem_cache *ntfs_index_ctx_cache;

/* Driver wide mutex. */
DEFINE_MUTEX(ntfs_lock);

static int ntfs_get_tree(struct fs_context *fc)
{
        return get_tree_bdev(fc, ntfs_fill_super);
}

static void ntfs_free_fs_context(struct fs_context *fc)
{
        struct ntfs_volume *vol = fc->s_fs_info;

        if (vol)
                ntfs_volume_free(vol);
}

static const struct fs_context_operations ntfs_context_ops = {
        .parse_param    = ntfs_parse_param,
        .get_tree       = ntfs_get_tree,
        .free           = ntfs_free_fs_context,
        .reconfigure    = ntfs_reconfigure,
};

static int ntfs_init_fs_context(struct fs_context *fc)
{
        struct ntfs_volume *vol;

        /* Allocate a new struct ntfs_volume and place it in sb->s_fs_info. */
        vol = kmalloc(sizeof(struct ntfs_volume), GFP_NOFS);
        if (!vol)
                return -ENOMEM;

        /* Initialize struct ntfs_volume structure. */
        *vol = (struct ntfs_volume) {
                .uid = INVALID_UID,
                .gid = INVALID_GID,
                .fmask = 0,
                .dmask = 0,
                .mft_zone_multiplier = 1,
                .on_errors = ON_ERRORS_CONTINUE,
                .nls_map = load_nls_default(),
                .preallocated_size = NTFS_DEF_PREALLOC_SIZE,
        };

        NVolSetShowHiddenFiles(vol);
        NVolSetCaseSensitive(vol);
        init_rwsem(&vol->mftbmp_lock);
        init_rwsem(&vol->lcnbmp_lock);
        mutex_init(&vol->volume_label_lock);

        fc->s_fs_info = vol;
        fc->ops = &ntfs_context_ops;
        return 0;
}

static struct file_system_type ntfs_fs_type = {
        .owner                  = THIS_MODULE,
        .name                   = "ntfs",
        .init_fs_context        = ntfs_init_fs_context,
        .parameters             = ntfs_parameters,
        .kill_sb                = kill_block_super,
        .fs_flags               = FS_REQUIRES_DEV | FS_ALLOW_IDMAP,
};
MODULE_ALIAS_FS("ntfs");

static int ntfs_workqueue_init(void)
{
        ntfs_wq = alloc_workqueue("ntfs-bg-io", WQ_PERCPU, 0);
        if (!ntfs_wq)
                return -ENOMEM;
        return 0;
}

static void ntfs_workqueue_destroy(void)
{
        destroy_workqueue(ntfs_wq);
        ntfs_wq = NULL;
}

/* Stable names for the slab caches. */
static const char ntfs_index_ctx_cache_name[] = "ntfs_index_ctx_cache";
static const char ntfs_attr_ctx_cache_name[] = "ntfs_attr_ctx_cache";
static const char ntfs_name_cache_name[] = "ntfs_name_cache";
static const char ntfs_inode_cache_name[] = "ntfs_inode_cache";
static const char ntfs_big_inode_cache_name[] = "ntfs_big_inode_cache";

static int __init init_ntfs_fs(void)
{
        int err = 0;

        err = ntfs_workqueue_init();
        if (err) {
                pr_crit("Failed to register workqueue!\n");
                return err;
        }

        ntfs_index_ctx_cache = kmem_cache_create(ntfs_index_ctx_cache_name,
                        sizeof(struct ntfs_index_context), 0 /* offset */,
                        SLAB_HWCACHE_ALIGN, NULL /* ctor */);
        if (!ntfs_index_ctx_cache) {
                pr_crit("Failed to create %s!\n", ntfs_index_ctx_cache_name);
                goto ictx_err_out;
        }
        ntfs_attr_ctx_cache = kmem_cache_create(ntfs_attr_ctx_cache_name,
                        sizeof(struct ntfs_attr_search_ctx), 0 /* offset */,
                        SLAB_HWCACHE_ALIGN, NULL /* ctor */);
        if (!ntfs_attr_ctx_cache) {
                pr_crit("NTFS: Failed to create %s!\n",
                        ntfs_attr_ctx_cache_name);
                goto actx_err_out;
        }

        ntfs_name_cache = kmem_cache_create(ntfs_name_cache_name,
                        (NTFS_MAX_NAME_LEN+2) * sizeof(__le16), 0,
                        SLAB_HWCACHE_ALIGN, NULL);
        if (!ntfs_name_cache) {
                pr_crit("Failed to create %s!\n", ntfs_name_cache_name);
                goto name_err_out;
        }

        ntfs_inode_cache = kmem_cache_create(ntfs_inode_cache_name,
                        sizeof(struct ntfs_inode), 0, SLAB_RECLAIM_ACCOUNT, NULL);
        if (!ntfs_inode_cache) {
                pr_crit("Failed to create %s!\n", ntfs_inode_cache_name);
                goto inode_err_out;
        }

        ntfs_big_inode_cache = kmem_cache_create(ntfs_big_inode_cache_name,
                        sizeof(struct big_ntfs_inode), 0, SLAB_HWCACHE_ALIGN |
                        SLAB_RECLAIM_ACCOUNT | SLAB_ACCOUNT,
                        ntfs_big_inode_init_once);
        if (!ntfs_big_inode_cache) {
                pr_crit("Failed to create %s!\n", ntfs_big_inode_cache_name);
                goto big_inode_err_out;
        }

        /* Register the ntfs sysctls. */
        err = ntfs_sysctl(1);
        if (err) {
                pr_crit("Failed to register NTFS sysctls!\n");
                goto sysctl_err_out;
        }

        err = register_filesystem(&ntfs_fs_type);
        if (!err) {
                ntfs_debug("NTFS driver registered successfully.");
                return 0; /* Success! */
        }
        pr_crit("Failed to register NTFS filesystem driver!\n");

        /* Unregister the ntfs sysctls. */
        ntfs_sysctl(0);
sysctl_err_out:
        kmem_cache_destroy(ntfs_big_inode_cache);
big_inode_err_out:
        kmem_cache_destroy(ntfs_inode_cache);
inode_err_out:
        kmem_cache_destroy(ntfs_name_cache);
name_err_out:
        kmem_cache_destroy(ntfs_attr_ctx_cache);
actx_err_out:
        kmem_cache_destroy(ntfs_index_ctx_cache);
ictx_err_out:
        if (!err) {
                pr_crit("Aborting NTFS filesystem driver registration...\n");
                err = -ENOMEM;
        }
        return err;
}

static void __exit exit_ntfs_fs(void)
{
        ntfs_debug("Unregistering NTFS driver.");

        unregister_filesystem(&ntfs_fs_type);

        /*
         * Make sure all delayed rcu free inodes are flushed before we
         * destroy cache.
         */
        rcu_barrier();
        kmem_cache_destroy(ntfs_big_inode_cache);
        kmem_cache_destroy(ntfs_inode_cache);
        kmem_cache_destroy(ntfs_name_cache);
        kmem_cache_destroy(ntfs_attr_ctx_cache);
        kmem_cache_destroy(ntfs_index_ctx_cache);
        ntfs_workqueue_destroy();
        /* Unregister the ntfs sysctls. */
        ntfs_sysctl(0);
}

module_init(init_ntfs_fs);
module_exit(exit_ntfs_fs);

MODULE_AUTHOR("Anton Altaparmakov <anton@tuxera.com>"); /* Original read-only NTFS driver */
MODULE_AUTHOR("Namjae Jeon <linkinjeon@kernel.org>"); /* Add write, iomap and various features */
MODULE_DESCRIPTION("NTFS read-write filesystem driver");
MODULE_LICENSE("GPL");
#ifdef DEBUG
module_param(debug_msgs, uint, 0);
MODULE_PARM_DESC(debug_msgs, "Enable debug messages.");
#endif