// SPDX-License-Identifier: GPL-2.0-or-later
/*
 * NTFS attribute operations.
 *
 * Copyright (c) 2001-2012 Anton Altaparmakov and Tuxera Inc.
 * Copyright (c) 2002 Richard Russon
 * Copyright (c) 2025 LG Electronics Co., Ltd.
 *
 * Part of this file is based on code from the NTFS-3G.
 * and is copyrighted by the respective authors below:
 * Copyright (c) 2000-2010 Anton Altaparmakov
 * Copyright (c) 2002-2005 Richard Russon
 * Copyright (c) 2002-2008 Szabolcs Szakacsits
 * Copyright (c) 2004-2007 Yura Pakhuchiy
 * Copyright (c) 2007-2021 Jean-Pierre Andre
 * Copyright (c) 2010 Erik Larsson
 */

#include <linux/string_choices.h>
#include <linux/writeback.h>
#include <linux/iomap.h>

#include "attrib.h"
#include "attrlist.h"
#include "lcnalloc.h"
#include "debug.h"
#include "mft.h"
#include "ntfs.h"
#include "iomap.h"

__le16 AT_UNNAMED[] = { cpu_to_le16('\0') };

/*
 * Maximum size allowed for reading attributes by ntfs_attr_readall().
 * Extended attribute, reparse point are not expected to be larger than this size.
 */

#define NTFS_ATTR_READALL_MAX_SIZE      (64 * 1024)

/*
 * ntfs_map_runlist_nolock - map (a part of) a runlist of an ntfs inode
 * @ni:         ntfs inode for which to map (part of) a runlist
 * @vcn:        map runlist part containing this vcn
 * @ctx:        active attribute search context if present or NULL if not
 *
 * Map the part of a runlist containing the @vcn of the ntfs inode @ni.
 *
 * If @ctx is specified, it is an active search context of @ni and its base mft
 * record.  This is needed when ntfs_map_runlist_nolock() encounters unmapped
 * runlist fragments and allows their mapping.  If you do not have the mft
 * record mapped, you can specify @ctx as NULL and ntfs_map_runlist_nolock()
 * will perform the necessary mapping and unmapping.
 *
 * Note, ntfs_map_runlist_nolock() saves the state of @ctx on entry and
 * restores it before returning.  Thus, @ctx will be left pointing to the same
 * attribute on return as on entry.  However, the actual pointers in @ctx may
 * point to different memory locations on return, so you must remember to reset
 * any cached pointers from the @ctx, i.e. after the call to
 * ntfs_map_runlist_nolock(), you will probably want to do:
 *      m = ctx->mrec;
 *      a = ctx->attr;
 * Assuming you cache ctx->attr in a variable @a of type struct attr_record *
 * and that you cache ctx->mrec in a variable @m of type struct mft_record *.
 *
 * Return 0 on success and -errno on error.  There is one special error code
 * which is not an error as such.  This is -ENOENT.  It means that @vcn is out
 * of bounds of the runlist.
 *
 * Note the runlist can be NULL after this function returns if @vcn is zero and
 * the attribute has zero allocated size, i.e. there simply is no runlist.
 *
 * WARNING: If @ctx is supplied, regardless of whether success or failure is
 *          returned, you need to check IS_ERR(@ctx->mrec) and if 'true' the @ctx
 *          is no longer valid, i.e. you need to either call
 *          ntfs_attr_reinit_search_ctx() or ntfs_attr_put_search_ctx() on it.
 *          In that case PTR_ERR(@ctx->mrec) will give you the error code for
 *          why the mapping of the old inode failed.
 *
 * Locking: - The runlist described by @ni must be locked for writing on entry
 *            and is locked on return.  Note the runlist will be modified.
 *          - If @ctx is NULL, the base mft record of @ni must not be mapped on
 *            entry and it will be left unmapped on return.
 *          - If @ctx is not NULL, the base mft record must be mapped on entry
 *            and it will be left mapped on return.
 */
int ntfs_map_runlist_nolock(struct ntfs_inode *ni, s64 vcn, struct ntfs_attr_search_ctx *ctx)
{
        s64 end_vcn;
        unsigned long flags;
        struct ntfs_inode *base_ni;
        struct mft_record *m;
        struct attr_record *a;
        struct runlist_element *rl;
        struct folio *put_this_folio = NULL;
        int err = 0;
        bool ctx_is_temporary = false, ctx_needs_reset = false;
        struct ntfs_attr_search_ctx old_ctx = { NULL, };
        size_t new_rl_count;

        ntfs_debug("Mapping runlist part containing vcn 0x%llx.",
                        (unsigned long long)vcn);
        if (!NInoAttr(ni))
                base_ni = ni;
        else
                base_ni = ni->ext.base_ntfs_ino;
        if (!ctx) {
                ctx_is_temporary = ctx_needs_reset = true;
                m = map_mft_record(base_ni);
                if (IS_ERR(m))
                        return PTR_ERR(m);
                ctx = ntfs_attr_get_search_ctx(base_ni, m);
                if (unlikely(!ctx)) {
                        err = -ENOMEM;
                        goto err_out;
                }
        } else {
                s64 allocated_size_vcn;

                WARN_ON(IS_ERR(ctx->mrec));
                a = ctx->attr;
                if (!a->non_resident) {
                        err = -EIO;
                        goto err_out;
                }
                end_vcn = le64_to_cpu(a->data.non_resident.highest_vcn);
                read_lock_irqsave(&ni->size_lock, flags);
                allocated_size_vcn =
                        ntfs_bytes_to_cluster(ni->vol, ni->allocated_size);
                read_unlock_irqrestore(&ni->size_lock, flags);
                if (!a->data.non_resident.lowest_vcn && end_vcn <= 0)
                        end_vcn = allocated_size_vcn - 1;
                /*
                 * If we already have the attribute extent containing @vcn in
                 * @ctx, no need to look it up again.  We slightly cheat in
                 * that if vcn exceeds the allocated size, we will refuse to
                 * map the runlist below, so there is definitely no need to get
                 * the right attribute extent.
                 */
                if (vcn >= allocated_size_vcn || (a->type == ni->type &&
                                a->name_length == ni->name_len &&
                                !memcmp((u8 *)a + le16_to_cpu(a->name_offset),
                                ni->name, ni->name_len) &&
                                le64_to_cpu(a->data.non_resident.lowest_vcn)
                                <= vcn && end_vcn >= vcn))
                        ctx_needs_reset = false;
                else {
                        /* Save the old search context. */
                        old_ctx = *ctx;
                        /*
                         * If the currently mapped (extent) inode is not the
                         * base inode we will unmap it when we reinitialize the
                         * search context which means we need to get a
                         * reference to the page containing the mapped mft
                         * record so we do not accidentally drop changes to the
                         * mft record when it has not been marked dirty yet.
                         */
                        if (old_ctx.base_ntfs_ino && old_ctx.ntfs_ino !=
                                        old_ctx.base_ntfs_ino) {
                                put_this_folio = old_ctx.ntfs_ino->folio;
                                folio_get(put_this_folio);
                        }
                        /*
                         * Reinitialize the search context so we can lookup the
                         * needed attribute extent.
                         */
                        ntfs_attr_reinit_search_ctx(ctx);
                        ctx_needs_reset = true;
                }
        }
        if (ctx_needs_reset) {
                err = ntfs_attr_lookup(ni->type, ni->name, ni->name_len,
                                CASE_SENSITIVE, vcn, NULL, 0, ctx);
                if (unlikely(err)) {
                        if (err == -ENOENT)
                                err = -EIO;
                        goto err_out;
                }
                if (unlikely(!ctx->attr->non_resident)) {
                        err = -EIO;
                        goto err_out;
                }
        }
        a = ctx->attr;
        /*
         * Only decompress the mapping pairs if @vcn is inside it.  Otherwise
         * we get into problems when we try to map an out of bounds vcn because
         * we then try to map the already mapped runlist fragment and
         * ntfs_mapping_pairs_decompress() fails.
         */
        end_vcn = le64_to_cpu(a->data.non_resident.highest_vcn) + 1;
        if (unlikely(vcn && vcn >= end_vcn)) {
                err = -ENOENT;
                goto err_out;
        }
        rl = ntfs_mapping_pairs_decompress(ni->vol, a, &ni->runlist, &new_rl_count);
        if (IS_ERR(rl))
                err = PTR_ERR(rl);
        else {
                ni->runlist.rl = rl;
                ni->runlist.count = new_rl_count;
        }
err_out:
        if (ctx_is_temporary) {
                if (likely(ctx))
                        ntfs_attr_put_search_ctx(ctx);
                unmap_mft_record(base_ni);
        } else if (ctx_needs_reset) {
                /*
                 * If there is no attribute list, restoring the search context
                 * is accomplished simply by copying the saved context back over
                 * the caller supplied context.  If there is an attribute list,
                 * things are more complicated as we need to deal with mapping
                 * of mft records and resulting potential changes in pointers.
                 */
                if (NInoAttrList(base_ni)) {
                        /*
                         * If the currently mapped (extent) inode is not the
                         * one we had before, we need to unmap it and map the
                         * old one.
                         */
                        if (ctx->ntfs_ino != old_ctx.ntfs_ino) {
                                /*
                                 * If the currently mapped inode is not the
                                 * base inode, unmap it.
                                 */
                                if (ctx->base_ntfs_ino && ctx->ntfs_ino !=
                                                ctx->base_ntfs_ino) {
                                        unmap_extent_mft_record(ctx->ntfs_ino);
                                        ctx->mrec = ctx->base_mrec;
                                        WARN_ON(!ctx->mrec);
                                }
                                /*
                                 * If the old mapped inode is not the base
                                 * inode, map it.
                                 */
                                if (old_ctx.base_ntfs_ino &&
                                    old_ctx.ntfs_ino != old_ctx.base_ntfs_ino) {
retry_map:
                                        ctx->mrec = map_mft_record(old_ctx.ntfs_ino);
                                        /*
                                         * Something bad has happened.  If out
                                         * of memory retry till it succeeds.
                                         * Any other errors are fatal and we
                                         * return the error code in ctx->mrec.
                                         * Let the caller deal with it...  We
                                         * just need to fudge things so the
                                         * caller can reinit and/or put the
                                         * search context safely.
                                         */
                                        if (IS_ERR(ctx->mrec)) {
                                                if (PTR_ERR(ctx->mrec) == -ENOMEM) {
                                                        schedule();
                                                        goto retry_map;
                                                } else
                                                        old_ctx.ntfs_ino =
                                                                old_ctx.base_ntfs_ino;
                                        }
                                }
                        }
                        /* Update the changed pointers in the saved context. */
                        if (ctx->mrec != old_ctx.mrec) {
                                if (!IS_ERR(ctx->mrec))
                                        old_ctx.attr = (struct attr_record *)(
                                                        (u8 *)ctx->mrec +
                                                        ((u8 *)old_ctx.attr -
                                                        (u8 *)old_ctx.mrec));
                                old_ctx.mrec = ctx->mrec;
                        }
                }
                /* Restore the search context to the saved one. */
                *ctx = old_ctx;
                /*
                 * We drop the reference on the page we took earlier.  In the
                 * case that IS_ERR(ctx->mrec) is true this means we might lose
                 * some changes to the mft record that had been made between
                 * the last time it was marked dirty/written out and now.  This
                 * at this stage is not a problem as the mapping error is fatal
                 * enough that the mft record cannot be written out anyway and
                 * the caller is very likely to shutdown the whole inode
                 * immediately and mark the volume dirty for chkdsk to pick up
                 * the pieces anyway.
                 */
                if (put_this_folio)
                        folio_put(put_this_folio);
        }
        return err;
}

/*
 * ntfs_map_runlist - map (a part of) a runlist of an ntfs inode
 * @ni:         ntfs inode for which to map (part of) a runlist
 * @vcn:        map runlist part containing this vcn
 *
 * Map the part of a runlist containing the @vcn of the ntfs inode @ni.
 *
 * Return 0 on success and -errno on error.  There is one special error code
 * which is not an error as such.  This is -ENOENT.  It means that @vcn is out
 * of bounds of the runlist.
 *
 * Locking: - The runlist must be unlocked on entry and is unlocked on return.
 *          - This function takes the runlist lock for writing and may modify
 *            the runlist.
 */
int ntfs_map_runlist(struct ntfs_inode *ni, s64 vcn)
{
        int err = 0;

        down_write(&ni->runlist.lock);
        /* Make sure someone else didn't do the work while we were sleeping. */
        if (likely(ntfs_rl_vcn_to_lcn(ni->runlist.rl, vcn) <=
                        LCN_RL_NOT_MAPPED))
                err = ntfs_map_runlist_nolock(ni, vcn, NULL);
        up_write(&ni->runlist.lock);
        return err;
}

struct runlist_element *ntfs_attr_vcn_to_rl(struct ntfs_inode *ni, s64 vcn, s64 *lcn)
{
        struct runlist_element *rl = ni->runlist.rl;
        int err;
        bool is_retry = false;

        if (!rl) {
                err = ntfs_attr_map_whole_runlist(ni);
                if (err)
                        return ERR_PTR(-ENOENT);
                rl = ni->runlist.rl;
        }

remap_rl:
        /* Seek to element containing target vcn. */
        while (rl->length && rl[1].vcn <= vcn)
                rl++;
        *lcn = ntfs_rl_vcn_to_lcn(rl, vcn);

        if (*lcn <= LCN_RL_NOT_MAPPED && is_retry == false) {
                is_retry = true;
                if (!ntfs_map_runlist_nolock(ni, vcn, NULL)) {
                        rl = ni->runlist.rl;
                        goto remap_rl;
                }
        }

        return rl;
}

/*
 * ntfs_attr_vcn_to_lcn_nolock - convert a vcn into a lcn given an ntfs inode
 * @ni:                 ntfs inode of the attribute whose runlist to search
 * @vcn:                vcn to convert
 * @write_locked:       true if the runlist is locked for writing
 *
 * Find the virtual cluster number @vcn in the runlist of the ntfs attribute
 * described by the ntfs inode @ni and return the corresponding logical cluster
 * number (lcn).
 *
 * If the @vcn is not mapped yet, the attempt is made to map the attribute
 * extent containing the @vcn and the vcn to lcn conversion is retried.
 *
 * If @write_locked is true the caller has locked the runlist for writing and
 * if false for reading.
 *
 * Since lcns must be >= 0, we use negative return codes with special meaning:
 *
 * Return code  Meaning / Description
 * ==========================================
 *  LCN_HOLE    Hole / not allocated on disk.
 *  LCN_ENOENT  There is no such vcn in the runlist, i.e. @vcn is out of bounds.
 *  LCN_ENOMEM  Not enough memory to map runlist.
 *  LCN_EIO     Critical error (runlist/file is corrupt, i/o error, etc).
 *
 * Locking: - The runlist must be locked on entry and is left locked on return.
 *          - If @write_locked is 'false', i.e. the runlist is locked for reading,
 *            the lock may be dropped inside the function so you cannot rely on
 *            the runlist still being the same when this function returns.
 */
s64 ntfs_attr_vcn_to_lcn_nolock(struct ntfs_inode *ni, const s64 vcn,
                const bool write_locked)
{
        s64 lcn;
        unsigned long flags;
        bool is_retry = false;

        ntfs_debug("Entering for i_ino 0x%llx, vcn 0x%llx, %s_locked.",
                        ni->mft_no, (unsigned long long)vcn,
                        write_locked ? "write" : "read");
        if (!ni->runlist.rl) {
                read_lock_irqsave(&ni->size_lock, flags);
                if (!ni->allocated_size) {
                        read_unlock_irqrestore(&ni->size_lock, flags);
                        return LCN_ENOENT;
                }
                read_unlock_irqrestore(&ni->size_lock, flags);
        }
retry_remap:
        /* Convert vcn to lcn.  If that fails map the runlist and retry once. */
        lcn = ntfs_rl_vcn_to_lcn(ni->runlist.rl, vcn);
        if (likely(lcn >= LCN_HOLE)) {
                ntfs_debug("Done, lcn 0x%llx.", (long long)lcn);
                return lcn;
        }
        if (lcn != LCN_RL_NOT_MAPPED) {
                if (lcn != LCN_ENOENT)
                        lcn = LCN_EIO;
        } else if (!is_retry) {
                int err;

                if (!write_locked) {
                        up_read(&ni->runlist.lock);
                        down_write(&ni->runlist.lock);
                        if (unlikely(ntfs_rl_vcn_to_lcn(ni->runlist.rl, vcn) !=
                                        LCN_RL_NOT_MAPPED)) {
                                up_write(&ni->runlist.lock);
                                down_read(&ni->runlist.lock);
                                goto retry_remap;
                        }
                }
                err = ntfs_map_runlist_nolock(ni, vcn, NULL);
                if (!write_locked) {
                        up_write(&ni->runlist.lock);
                        down_read(&ni->runlist.lock);
                }
                if (likely(!err)) {
                        is_retry = true;
                        goto retry_remap;
                }
                if (err == -ENOENT)
                        lcn = LCN_ENOENT;
                else if (err == -ENOMEM)
                        lcn = LCN_ENOMEM;
                else
                        lcn = LCN_EIO;
        }
        if (lcn != LCN_ENOENT)
                ntfs_error(ni->vol->sb, "Failed with error code %lli.",
                                (long long)lcn);
        return lcn;
}

struct runlist_element *__ntfs_attr_find_vcn_nolock(struct runlist *runlist, const s64 vcn)
{
        size_t lower_idx, upper_idx, idx;
        struct runlist_element *run;
        int rh = runlist->rl_hint;

        if (runlist->count <= 1)
                return ERR_PTR(-ENOENT);

        if (runlist->count - 1 > rh && runlist->rl[rh].vcn <= vcn) {
                if (vcn < runlist->rl[rh].vcn + runlist->rl[rh].length)
                        return &runlist->rl[rh];
                if (runlist->count - 2 == rh)
                        return ERR_PTR(-ENOENT);

                lower_idx = rh + 1;
        } else {
                run = &runlist->rl[0];
                if (vcn < run->vcn)
                        return ERR_PTR(-ENOENT);
                else if (vcn < run->vcn + run->length) {
                        runlist->rl_hint = 0;
                        return run;
                }

                lower_idx = 1;
        }

        run = &runlist->rl[runlist->count - 2];
        if (vcn >= run->vcn && vcn < run->vcn + run->length) {
                runlist->rl_hint = runlist->count - 2;
                return run;
        }
        if (vcn >= run->vcn + run->length)
                return ERR_PTR(-ENOENT);

        upper_idx = runlist->count - 2;

        while (lower_idx <= upper_idx) {
                idx = (lower_idx + upper_idx) >> 1;
                run = &runlist->rl[idx];

                if (vcn < run->vcn)
                        upper_idx = idx - 1;
                else if (vcn >= run->vcn + run->length)
                        lower_idx = idx + 1;
                else {
                        runlist->rl_hint = idx;
                        return run;
                }
        }

        return ERR_PTR(-ENOENT);
}

/*
 * ntfs_attr_find_vcn_nolock - find a vcn in the runlist of an ntfs inode
 * @ni:         ntfs inode describing the runlist to search
 * @vcn:        vcn to find
 * @ctx:        active attribute search context if present or NULL if not
 *
 * Find the virtual cluster number @vcn in the runlist described by the ntfs
 * inode @ni and return the address of the runlist element containing the @vcn.
 *
 * If the @vcn is not mapped yet, the attempt is made to map the attribute
 * extent containing the @vcn and the vcn to lcn conversion is retried.
 *
 * If @ctx is specified, it is an active search context of @ni and its base mft
 * record.  This is needed when ntfs_attr_find_vcn_nolock() encounters unmapped
 * runlist fragments and allows their mapping.  If you do not have the mft
 * record mapped, you can specify @ctx as NULL and ntfs_attr_find_vcn_nolock()
 * will perform the necessary mapping and unmapping.
 *
 * Note, ntfs_attr_find_vcn_nolock() saves the state of @ctx on entry and
 * restores it before returning.  Thus, @ctx will be left pointing to the same
 * attribute on return as on entry.  However, the actual pointers in @ctx may
 * point to different memory locations on return, so you must remember to reset
 * any cached pointers from the @ctx, i.e. after the call to
 * ntfs_attr_find_vcn_nolock(), you will probably want to do:
 *      m = ctx->mrec;
 *      a = ctx->attr;
 * Assuming you cache ctx->attr in a variable @a of type attr_record * and that
 * you cache ctx->mrec in a variable @m of type struct mft_record *.
 * Note you need to distinguish between the lcn of the returned runlist element
 * being >= 0 and LCN_HOLE.  In the later case you have to return zeroes on
 * read and allocate clusters on write.
 */
struct runlist_element *ntfs_attr_find_vcn_nolock(struct ntfs_inode *ni, const s64 vcn,
                struct ntfs_attr_search_ctx *ctx)
{
        unsigned long flags;
        struct runlist_element *rl;
        int err = 0;
        bool is_retry = false;

        ntfs_debug("Entering for i_ino 0x%llx, vcn 0x%llx, with%s ctx.",
                        ni->mft_no, (unsigned long long)vcn, ctx ? "" : "out");
        if (!ni->runlist.rl) {
                read_lock_irqsave(&ni->size_lock, flags);
                if (!ni->allocated_size) {
                        read_unlock_irqrestore(&ni->size_lock, flags);
                        return ERR_PTR(-ENOENT);
                }
                read_unlock_irqrestore(&ni->size_lock, flags);
        }

retry_remap:
        rl = ni->runlist.rl;
        if (likely(rl && vcn >= rl[0].vcn)) {
                rl = __ntfs_attr_find_vcn_nolock(&ni->runlist, vcn);
                if (IS_ERR(rl))
                        err = PTR_ERR(rl);
                else if (rl->lcn >= LCN_HOLE)
                        return rl;
                else if (rl->lcn <= LCN_ENOENT)
                        err = -EIO;
        }
        if (!err && !is_retry) {
                /*
                 * If the search context is invalid we cannot map the unmapped
                 * region.
                 */
                if (ctx && IS_ERR(ctx->mrec))
                        err = PTR_ERR(ctx->mrec);
                else {
                        /*
                         * The @vcn is in an unmapped region, map the runlist
                         * and retry.
                         */
                        err = ntfs_map_runlist_nolock(ni, vcn, ctx);
                        if (likely(!err)) {
                                is_retry = true;
                                goto retry_remap;
                        }
                }
                if (err == -EINVAL)
                        err = -EIO;
        } else if (!err)
                err = -EIO;
        if (err != -ENOENT)
                ntfs_error(ni->vol->sb, "Failed with error code %i.", err);
        return ERR_PTR(err);
}

static u32 ntfs_resident_attr_min_value_length(const __le32 type)
{
        switch (type) {
        case AT_STANDARD_INFORMATION:
                return offsetof(struct standard_information, ver) +
                       sizeof(((struct standard_information *)0)->ver.v1.reserved12);
        case AT_FILE_NAME:
                return offsetof(struct file_name_attr, file_name) +
                        sizeof(__le16) * 1;
        case AT_VOLUME_INFORMATION:
                return sizeof(struct volume_information);
        case AT_INDEX_ROOT:
                return sizeof(struct index_root);
        case AT_EA_INFORMATION:
                return sizeof(struct ea_information);
        default:
                return 0;
        }
}

static bool ntfs_attr_type_is_resident_only(const __le32 type)
{
        switch (type) {
        case AT_STANDARD_INFORMATION:
        case AT_FILE_NAME:
        case AT_OBJECT_ID:
        case AT_VOLUME_NAME:
        case AT_VOLUME_INFORMATION:
        case AT_INDEX_ROOT:
        case AT_EA_INFORMATION:
                return true;
        default:
                return false;
        }
}

static bool ntfs_file_name_attr_value_is_valid(const u8 *value, const u32 value_length)
{
        const struct file_name_attr *fn;
        u32 file_name_size;

        fn = (const struct file_name_attr *)value;
        file_name_size = fn->file_name_length * sizeof(__le16);

        return file_name_size <=
                        value_length - offsetof(struct file_name_attr, file_name);
}

static bool ntfs_volume_name_attr_value_is_valid(const u32 value_length)
{
        if (value_length & 1)
                return false;

        return value_length <= NTFS_MAX_LABEL_LEN * sizeof(__le16);
}

static bool ntfs_index_root_attr_value_is_valid(const u8 *value, const u32 value_length)
{
        const struct index_root *ir;
        u32 index_size;
        u32 entries_offset;
        u32 index_length;
        u32 allocated_size;

        ir = (const struct index_root *)value;
        index_size = value_length - offsetof(struct index_root, index);
        entries_offset = le32_to_cpu(ir->index.entries_offset);
        index_length = le32_to_cpu(ir->index.index_length);
        allocated_size = le32_to_cpu(ir->index.allocated_size);

        if ((entries_offset | index_length | allocated_size) & 7 ||
            entries_offset < sizeof(struct index_header) ||
            entries_offset > index_length ||
            index_length > allocated_size ||
            allocated_size > index_size ||
            index_length - entries_offset < sizeof(struct index_entry_header))
                return false;

        return true;
}

struct ntfs_resident_attr_value {
        const u8 *data;
        u32 len;
};

static bool ntfs_resident_attr_value_get(const struct attr_record *a,
                                         struct ntfs_resident_attr_value *value)
{
        u32 attr_len;
        u16 value_offset;

        attr_len = le32_to_cpu(a->length);
        if (attr_len < offsetof(struct attr_record, data.resident.reserved) +
                        sizeof(a->data.resident.reserved))
                return false;

        value->len = le32_to_cpu(a->data.resident.value_length);
        value_offset = le16_to_cpu(a->data.resident.value_offset);

        if (value->len > attr_len || value_offset > attr_len - value->len)
                return false;

        value->data = (const u8 *)a + value_offset;
        return true;
}

static bool ntfs_non_resident_attr_value_is_valid(const struct attr_record *a)
{
        u32 attr_len;
        u32 min_len;
        u16 mp_offset;

        attr_len = le32_to_cpu(a->length);
        min_len = offsetof(struct attr_record, data.non_resident.initialized_size) +
                  sizeof(a->data.non_resident.initialized_size);
        if (attr_len < min_len)
                return false;

        mp_offset = le16_to_cpu(a->data.non_resident.mapping_pairs_offset);
        return mp_offset >= min_len && mp_offset <= attr_len;
}

static bool ntfs_attr_value_is_valid(struct ntfs_volume *vol,
                                     const struct attr_record *a,
                                     const u64 mft_no)
{
        struct ntfs_resident_attr_value value;
        u32 min_len;

        if (a->non_resident) {
                if (ntfs_attr_type_is_resident_only(a->type))
                        goto corrupt;
                if (!ntfs_non_resident_attr_value_is_valid(a))
                        goto corrupt;
                return true;
        }

        if (!ntfs_resident_attr_value_get(a, &value))
                goto corrupt;

        min_len = ntfs_resident_attr_min_value_length(a->type);
        if (min_len && value.len < min_len)
                goto corrupt;

        switch (a->type) {
        case AT_FILE_NAME:
                if (!ntfs_file_name_attr_value_is_valid(value.data, value.len))
                        goto corrupt;
                break;
        case AT_VOLUME_NAME:
                if (!ntfs_volume_name_attr_value_is_valid(value.len))
                        goto corrupt;
                break;
        case AT_INDEX_ROOT:
                if (!ntfs_index_root_attr_value_is_valid(value.data, value.len))
                        goto corrupt;
                break;
        }
        return true;

corrupt:
        ntfs_error(vol->sb,
                   "Corrupt %#x attribute in MFT record %llu\n",
                   le32_to_cpu(a->type), mft_no);
        return false;
}

/*
 * ntfs_attr_find - find (next) attribute in mft record
 * @type:       attribute type to find
 * @name:       attribute name to find (optional, i.e. NULL means don't care)
 * @name_len:   attribute name length (only needed if @name present)
 * @ic:         IGNORE_CASE or CASE_SENSITIVE (ignored if @name not present)
 * @val:        attribute value to find (optional, resident attributes only)
 * @val_len:    attribute value length
 * @ctx:        search context with mft record and attribute to search from
 *
 * You should not need to call this function directly.  Use ntfs_attr_lookup()
 * instead.
 *
 * ntfs_attr_find() takes a search context @ctx as parameter and searches the
 * mft record specified by @ctx->mrec, beginning at @ctx->attr, for an
 * attribute of @type, optionally @name and @val.
 *
 * If the attribute is found, ntfs_attr_find() returns 0 and @ctx->attr will
 * point to the found attribute.
 *
 * If the attribute is not found, ntfs_attr_find() returns -ENOENT and
 * @ctx->attr will point to the attribute before which the attribute being
 * searched for would need to be inserted if such an action were to be desired.
 *
 * On actual error, ntfs_attr_find() returns -EIO.  In this case @ctx->attr is
 * undefined and in particular do not rely on it not changing.
 *
 * If @ctx->is_first is 'true', the search begins with @ctx->attr itself.  If it
 * is 'false', the search begins after @ctx->attr.
 *
 * If @ic is IGNORE_CASE, the @name comparisson is not case sensitive and
 * @ctx->ntfs_ino must be set to the ntfs inode to which the mft record
 * @ctx->mrec belongs.  This is so we can get at the ntfs volume and hence at
 * the upcase table.  If @ic is CASE_SENSITIVE, the comparison is case
 * sensitive.  When @name is present, @name_len is the @name length in Unicode
 * characters.
 *
 * If @name is not present (NULL), we assume that the unnamed attribute is
 * being searched for.
 *
 * Finally, the resident attribute value @val is looked for, if present.  If
 * @val is not present (NULL), @val_len is ignored.
 *
 * ntfs_attr_find() only searches the specified mft record and it ignores the
 * presence of an attribute list attribute (unless it is the one being searched
 * for, obviously).  If you need to take attribute lists into consideration,
 * use ntfs_attr_lookup() instead (see below).  This also means that you cannot
 * use ntfs_attr_find() to search for extent records of non-resident
 * attributes, as extents with lowest_vcn != 0 are usually described by the
 * attribute list attribute only. - Note that it is possible that the first
 * extent is only in the attribute list while the last extent is in the base
 * mft record, so do not rely on being able to find the first extent in the
 * base mft record.
 *
 * Warning: Never use @val when looking for attribute types which can be
 *          non-resident as this most likely will result in a crash!
 */
static int ntfs_attr_find(const __le32 type, const __le16 *name,
                const u32 name_len, const u32 ic,
                const u8 *val, const u32 val_len, struct ntfs_attr_search_ctx *ctx)
{
        struct attr_record *a;
        struct ntfs_volume *vol = ctx->ntfs_ino->vol;
        __le16 *upcase = vol->upcase;
        u32 upcase_len = vol->upcase_len;
        unsigned int space;
        u16 name_offset;
        u32 attr_len;
        u32 name_size;

        /*
         * Iterate over attributes in mft record starting at @ctx->attr, or the
         * attribute following that, if @ctx->is_first is 'true'.
         */
        if (ctx->is_first) {
                a = ctx->attr;
                ctx->is_first = false;
        } else
                a = (struct attr_record *)((u8 *)ctx->attr +
                                le32_to_cpu(ctx->attr->length));
        for (;; a = (struct attr_record *)((u8 *)a + le32_to_cpu(a->length))) {
                if ((u8 *)a < (u8 *)ctx->mrec || (u8 *)a > (u8 *)ctx->mrec +
                                le32_to_cpu(ctx->mrec->bytes_allocated))
                        break;

                space = le32_to_cpu(ctx->mrec->bytes_in_use) - ((u8 *)a - (u8 *)ctx->mrec);
                if ((space < offsetof(struct attr_record, data.resident.reserved) + 1 ||
                      space < le32_to_cpu(a->length)) && (space < 4 || a->type != AT_END))
                        break;

                ctx->attr = a;
                if (((type != AT_UNUSED) && (le32_to_cpu(a->type) > le32_to_cpu(type))) ||
                                a->type == AT_END)
                        return -ENOENT;
                if (unlikely(!a->length))
                        break;
                if (a->name_length) {
                        name_offset = le16_to_cpu(a->name_offset);
                        attr_len = le32_to_cpu(a->length);
                        name_size = a->name_length * sizeof(__le16);

                        if (name_offset > attr_len ||
                            attr_len - name_offset < name_size) {
                                ntfs_error(vol->sb,
                                           "Corrupt attribute name in MFT record %llu\n",
                                           ctx->ntfs_ino->mft_no);
                                break;
                        }
                }

                if (type == AT_UNUSED) {
                        if (!ntfs_attr_value_is_valid(vol, a, ctx->ntfs_ino->mft_no))
                                break;
                        return 0;
                }
                if (a->type != type)
                        continue;
                /*
                 * If @name is present, compare the two names.  If @name is
                 * missing, assume we want an unnamed attribute.
                 */
                if (!name || name == AT_UNNAMED) {
                        /* The search failed if the found attribute is named. */
                        if (a->name_length)
                                return -ENOENT;
                } else {
                        if (!ntfs_are_names_equal(name, name_len,
                                        (__le16 *)((u8 *)a + le16_to_cpu(a->name_offset)),
                                        a->name_length, ic, upcase, upcase_len)) {
                                register int rc;

                                rc = ntfs_collate_names(name, name_len,
                                                (__le16 *)((u8 *)a + le16_to_cpu(a->name_offset)),
                                                a->name_length, 1, IGNORE_CASE,
                                                upcase, upcase_len);
                                /*
                                 * If @name collates before a->name, there is no
                                 * matching attribute.
                                 */
                                if (rc == -1)
                                        return -ENOENT;
                                /* If the strings are not equal, continue search. */
                                if (rc)
                                        continue;
                                rc = ntfs_collate_names(name, name_len,
                                                (__le16 *)((u8 *)a + le16_to_cpu(a->name_offset)),
                                                a->name_length, 1, CASE_SENSITIVE,
                                                upcase, upcase_len);
                                if (rc == -1)
                                        return -ENOENT;
                                if (rc)
                                        continue;
                        }
                }

                if (!ntfs_attr_value_is_valid(vol, a, ctx->ntfs_ino->mft_no))
                        break;

                /*
                 * The names match or @name not present and attribute is
                 * unnamed.  If no @val specified, we have found the attribute
                 * and are done.
                 */
                if (!val || a->non_resident)
                        return 0;
                /* @val is present; compare values. */
                else {
                        u32 value_length = le32_to_cpu(a->data.resident.value_length);
                        int rc;

                        rc = memcmp(val, (u8 *)a + le16_to_cpu(
                                        a->data.resident.value_offset),
                                        min_t(u32, val_len, value_length));
                        /*
                         * If @val collates before the current attribute's
                         * value, there is no matching attribute.
                         */
                        if (!rc) {
                                if (val_len == value_length)
                                        return 0;
                                if (val_len < value_length)
                                        return -ENOENT;
                        } else if (rc < 0)
                                return -ENOENT;
                }
        }
        ntfs_error(vol->sb, "mft %#llx, type %#x is corrupt. Run chkdsk.",
                   (long long)ctx->ntfs_ino->mft_no, le32_to_cpu(type));
        NVolSetErrors(vol);
        return -EIO;
}

void ntfs_attr_name_free(unsigned char **name)
{
        if (*name) {
                kfree(*name);
                *name = NULL;
        }
}

char *ntfs_attr_name_get(const struct ntfs_volume *vol, const __le16 *uname,
                const int uname_len)
{
        unsigned char *name = NULL;
        int name_len;

        name_len = ntfs_ucstonls(vol, uname, uname_len, &name, 0);
        if (name_len < 0) {
                ntfs_error(vol->sb, "ntfs_ucstonls error");
                /* This function when returns -1, memory for name might
                 * be allocated. So lets free this memory.
                 */
                ntfs_attr_name_free(&name);
                return NULL;

        } else if (name_len > 0)
                return name;

        ntfs_attr_name_free(&name);
        return NULL;
}

/*
 * ntfs_attr_list_entry_is_valid - sanity check one $ATTRIBUTE_LIST entry
 * @ale:        the attribute-list entry to check
 * @al_end:     end of the attribute-list buffer @ale lives in
 *
 * Verify that @ale is a well-formed attr_list_entry wholly contained in
 * [.., @al_end): its fixed header must lie in range before any field is
 * dereferenced, its length must be a multiple of 8 that covers the fixed
 * header plus the name, the name must lie within the buffer, the entry must
 * be in use and carry a live MFT reference.  Return true if valid.
 */
bool ntfs_attr_list_entry_is_valid(const struct attr_list_entry *ale,
                                   const u8 *al_end)
{
        const u8 *al = (const u8 *)ale;
        u16 ale_len;

        /* The fixed header must be in bounds before it is parsed. */
        if (al + offsetof(struct attr_list_entry, name) > al_end)
                return false;
        ale_len = le16_to_cpu(ale->length);
        /* On-disk entries are 8-byte aligned (see struct attr_list_entry). */
        if (ale_len & 7)
                return false;
        if (ale->name_offset != sizeof(struct attr_list_entry))
                return false;
        if ((u32)ale->name_offset +
            (u32)ale->name_length * sizeof(__le16) > ale_len ||
            al + ale_len > al_end)
                return false;
        if (ale->type == AT_UNUSED)
                return false;
        if (MSEQNO_LE(ale->mft_reference) == 0)
                return false;
        return true;
}

/*
 * ntfs_attr_list_is_valid - sanity check an in-memory $ATTRIBUTE_LIST
 * @al_start:   start of the attribute list buffer
 * @size:       length of the attribute list in bytes
 *
 * Verify that [@al_start, @al_start + @size) is a sequence of valid
 * attr_list_entry records (see ntfs_attr_list_entry_is_valid()) that tile the
 * buffer exactly.  Return true if valid, false otherwise.
 */
bool ntfs_attr_list_is_valid(const u8 *al_start, s64 size)
{
        const u8 *al = al_start;
        const u8 *al_end = al_start + size;

        while (al < al_end) {
                const struct attr_list_entry *ale =
                                (const struct attr_list_entry *)al;

                if (!ntfs_attr_list_entry_is_valid(ale, al_end))
                        return false;
                al += le16_to_cpu(ale->length);
        }
        return al == al_end;
}

int load_attribute_list(struct ntfs_inode *base_ni, u8 *al_start, const s64 size)
{
        struct inode *attr_vi = NULL;

        if (!al_start || size <= 0)
                return -EINVAL;

        attr_vi = ntfs_attr_iget(VFS_I(base_ni), AT_ATTRIBUTE_LIST, AT_UNNAMED, 0);
        if (IS_ERR(attr_vi)) {
                ntfs_error(base_ni->vol->sb,
                           "Failed to open an inode for Attribute list, mft = %llu",
                           base_ni->mft_no);
                return PTR_ERR(attr_vi);
        }

        if (ntfs_inode_attr_pread(attr_vi, 0, size, al_start) != size) {
                iput(attr_vi);
                ntfs_error(base_ni->vol->sb,
                           "Failed to read attribute list, mft = %llu",
                           base_ni->mft_no);
                return -EIO;
        }
        iput(attr_vi);

        if (!ntfs_attr_list_is_valid(al_start, size)) {
                ntfs_error(base_ni->vol->sb, "Corrupt attribute list, mft = %llu",
                           base_ni->mft_no);
                return -EIO;
        }
        return 0;
}

/*
 * ntfs_external_attr_find - find an attribute in the attribute list of an inode
 * @type:       attribute type to find
 * @name:       attribute name to find (optional, i.e. NULL means don't care)
 * @name_len:   attribute name length (only needed if @name present)
 * @ic:         IGNORE_CASE or CASE_SENSITIVE (ignored if @name not present)
 * @lowest_vcn: lowest vcn to find (optional, non-resident attributes only)
 * @val:        attribute value to find (optional, resident attributes only)
 * @val_len:    attribute value length
 * @ctx:        search context with mft record and attribute to search from
 *
 * You should not need to call this function directly.  Use ntfs_attr_lookup()
 * instead.
 *
 * Find an attribute by searching the attribute list for the corresponding
 * attribute list entry.  Having found the entry, map the mft record if the
 * attribute is in a different mft record/inode, ntfs_attr_find() the attribute
 * in there and return it.
 *
 * On first search @ctx->ntfs_ino must be the base mft record and @ctx must
 * have been obtained from a call to ntfs_attr_get_search_ctx().  On subsequent
 * calls @ctx->ntfs_ino can be any extent inode, too (@ctx->base_ntfs_ino is
 * then the base inode).
 *
 * After finishing with the attribute/mft record you need to call
 * ntfs_attr_put_search_ctx() to cleanup the search context (unmapping any
 * mapped inodes, etc).
 *
 * If the attribute is found, ntfs_external_attr_find() returns 0 and
 * @ctx->attr will point to the found attribute.  @ctx->mrec will point to the
 * mft record in which @ctx->attr is located and @ctx->al_entry will point to
 * the attribute list entry for the attribute.
 *
 * If the attribute is not found, ntfs_external_attr_find() returns -ENOENT and
 * @ctx->attr will point to the attribute in the base mft record before which
 * the attribute being searched for would need to be inserted if such an action
 * were to be desired.  @ctx->mrec will point to the mft record in which
 * @ctx->attr is located and @ctx->al_entry will point to the attribute list
 * entry of the attribute before which the attribute being searched for would
 * need to be inserted if such an action were to be desired.
 *
 * Thus to insert the not found attribute, one wants to add the attribute to
 * @ctx->mrec (the base mft record) and if there is not enough space, the
 * attribute should be placed in a newly allocated extent mft record.  The
 * attribute list entry for the inserted attribute should be inserted in the
 * attribute list attribute at @ctx->al_entry.
 *
 * On actual error, ntfs_external_attr_find() returns -EIO.  In this case
 * @ctx->attr is undefined and in particular do not rely on it not changing.
 */
static int ntfs_external_attr_find(const __le32 type,
                const __le16 *name, const u32 name_len,
                const u32 ic, const s64 lowest_vcn,
                const u8 *val, const u32 val_len, struct ntfs_attr_search_ctx *ctx)
{
        struct ntfs_inode *base_ni = ctx->base_ntfs_ino, *ni = ctx->ntfs_ino;
        struct ntfs_volume *vol;
        struct attr_list_entry *al_entry, *next_al_entry;
        u8 *al_start, *al_end;
        struct attr_record *a;
        __le16 *al_name;
        u32 al_name_len;
        u32 attr_len, mft_free_len;
        bool is_first_search = false;
        int err = 0;
        static const char *es = " Unmount and run chkdsk.";

        ntfs_debug("Entering for inode 0x%llx, type 0x%x.", ni->mft_no, type);
        if (!base_ni) {
                /* First call happens with the base mft record. */
                base_ni = ctx->base_ntfs_ino = ctx->ntfs_ino;
                ctx->base_mrec = ctx->mrec;
                ctx->mapped_base_mrec = ctx->mapped_mrec;
        }
        if (ni == base_ni)
                ctx->base_attr = ctx->attr;
        if (type == AT_END)
                goto not_found;
        vol = base_ni->vol;
        al_start = base_ni->attr_list;
        al_end = al_start + base_ni->attr_list_size;
        if (!ctx->al_entry) {
                ctx->al_entry = (struct attr_list_entry *)al_start;
                is_first_search = true;
        }
        /*
         * Iterate over entries in attribute list starting at @ctx->al_entry,
         * or the entry following that, if @ctx->is_first is 'true'.
         */
        if (ctx->is_first) {
                al_entry = ctx->al_entry;
                ctx->is_first = false;
                /*
                 * If an enumeration and the first attribute is higher than
                 * the attribute list itself, need to return the attribute list
                 * attribute.
                 */
                if ((type == AT_UNUSED) && is_first_search &&
                                le32_to_cpu(al_entry->type) >
                                le32_to_cpu(AT_ATTRIBUTE_LIST))
                        goto find_attr_list_attr;
        } else {
                /* Check for small entry */
                if (((al_end - (u8 *)ctx->al_entry) <
                      (long)offsetof(struct attr_list_entry, name)) ||
                    (le16_to_cpu(ctx->al_entry->length) & 7) ||
                    (le16_to_cpu(ctx->al_entry->length) < offsetof(struct attr_list_entry, name)))
                        goto corrupt;

                al_entry = (struct attr_list_entry *)((u8 *)ctx->al_entry +
                                le16_to_cpu(ctx->al_entry->length));

                if ((u8 *)al_entry == al_end)
                        goto not_found;

                /* Preliminary check for small entry */
                if ((al_end - (u8 *)al_entry) <
                    (long)offsetof(struct attr_list_entry, name))
                        goto corrupt;

                /*
                 * If this is an enumeration and the attribute list attribute
                 * is the next one in the enumeration sequence, just return the
                 * attribute list attribute from the base mft record as it is
                 * not listed in the attribute list itself.
                 */
                if ((type == AT_UNUSED) && le32_to_cpu(ctx->al_entry->type) <
                                le32_to_cpu(AT_ATTRIBUTE_LIST) &&
                                le32_to_cpu(al_entry->type) >
                                le32_to_cpu(AT_ATTRIBUTE_LIST)) {
find_attr_list_attr:

                        /* Check for bogus calls. */
                        if (name || name_len || val || val_len || lowest_vcn)
                                return -EINVAL;

                        /* We want the base record. */
                        if (ctx->ntfs_ino != base_ni)
                                unmap_mft_record(ctx->ntfs_ino);
                        ctx->ntfs_ino = base_ni;
                        ctx->mapped_mrec = ctx->mapped_base_mrec;
                        ctx->mrec = ctx->base_mrec;
                        ctx->is_first = true;

                        /* Sanity checks are performed elsewhere. */
                        ctx->attr = (struct attr_record *)((u8 *)ctx->mrec +
                                        le16_to_cpu(ctx->mrec->attrs_offset));

                        /* Find the attribute list attribute. */
                        err = ntfs_attr_find(AT_ATTRIBUTE_LIST, NULL, 0,
                                        IGNORE_CASE, NULL, 0, ctx);

                        /*
                         * Setup the search context so the correct
                         * attribute is returned next time round.
                         */
                        ctx->al_entry = al_entry;
                        ctx->is_first = true;

                        /* Got it. Done. */
                        if (!err)
                                return 0;

                        /* Error! If other than not found return it. */
                        if (err != -ENOENT)
                                return err;

                        /* Not found?!? Absurd! */
                        ntfs_error(ctx->ntfs_ino->vol->sb, "Attribute list wasn't found");
                        return -EIO;
                }
        }
        for (;; al_entry = next_al_entry) {
                /* Out of bounds check. */
                if ((u8 *)al_entry < base_ni->attr_list ||
                                (u8 *)al_entry > al_end)
                        break;  /* Inode is corrupt. */
                ctx->al_entry = al_entry;
                /* Catch the end of the attribute list. */
                if ((u8 *)al_entry == al_end)
                        goto not_found;

                if ((((u8 *)al_entry + offsetof(struct attr_list_entry, name)) > al_end) ||
                    ((u8 *)al_entry + le16_to_cpu(al_entry->length) > al_end) ||
                    (le16_to_cpu(al_entry->length) & 7) ||
                    (le16_to_cpu(al_entry->length) <
                     offsetof(struct attr_list_entry, name_length)) ||
                    (al_entry->name_length && ((u8 *)al_entry + al_entry->name_offset +
                                               al_entry->name_length * sizeof(__le16)) > al_end))
                        break; /* corrupt */

                next_al_entry = (struct attr_list_entry *)((u8 *)al_entry +
                                le16_to_cpu(al_entry->length));
                if (type != AT_UNUSED) {
                        if (le32_to_cpu(al_entry->type) > le32_to_cpu(type))
                                goto not_found;
                        if (type != al_entry->type)
                                continue;
                }
                /*
                 * If @name is present, compare the two names.  If @name is
                 * missing, assume we want an unnamed attribute.
                 */
                al_name_len = al_entry->name_length;
                al_name = (__le16 *)((u8 *)al_entry + al_entry->name_offset);

                /*
                 * If !@type we want the attribute represented by this
                 * attribute list entry.
                 */
                if (type == AT_UNUSED)
                        goto is_enumeration;

                if (!name || name == AT_UNNAMED) {
                        if (al_name_len)
                                goto not_found;
                } else if (!ntfs_are_names_equal(al_name, al_name_len, name,
                                name_len, ic, vol->upcase, vol->upcase_len)) {
                        register int rc;

                        rc = ntfs_collate_names(name, name_len, al_name,
                                        al_name_len, 1, IGNORE_CASE,
                                        vol->upcase, vol->upcase_len);
                        /*
                         * If @name collates before al_name, there is no
                         * matching attribute.
                         */
                        if (rc == -1)
                                goto not_found;
                        /* If the strings are not equal, continue search. */
                        if (rc)
                                continue;

                        rc = ntfs_collate_names(name, name_len, al_name,
                                        al_name_len, 1, CASE_SENSITIVE,
                                        vol->upcase, vol->upcase_len);
                        if (rc == -1)
                                goto not_found;
                        if (rc)
                                continue;
                }
                /*
                 * The names match or @name not present and attribute is
                 * unnamed.  Now check @lowest_vcn.  Continue search if the
                 * next attribute list entry still fits @lowest_vcn.  Otherwise
                 * we have reached the right one or the search has failed.
                 */
                if (lowest_vcn && (u8 *)next_al_entry >= al_start &&
                                ntfs_attr_list_entry_is_valid(next_al_entry,
                                                              al_end) &&
                                le64_to_cpu(next_al_entry->lowest_vcn) <=
                                        lowest_vcn &&
                                next_al_entry->type == al_entry->type &&
                                next_al_entry->name_length == al_name_len &&
                                ntfs_are_names_equal((__le16 *)((u8 *)
                                        next_al_entry +
                                        next_al_entry->name_offset),
                                        next_al_entry->name_length,
                                        al_name, al_name_len, CASE_SENSITIVE,
                                        vol->upcase, vol->upcase_len))
                        continue;

is_enumeration:
                if (MREF_LE(al_entry->mft_reference) == ni->mft_no) {
                        if (MSEQNO_LE(al_entry->mft_reference) != ni->seq_no) {
                                ntfs_error(vol->sb,
                                        "Found stale mft reference in attribute list of base inode 0x%llx.%s",
                                        base_ni->mft_no, es);
                                err = -EIO;
                                break;
                        }
                } else { /* Mft references do not match. */
                        /* If there is a mapped record unmap it first. */
                        if (ni != base_ni)
                                unmap_extent_mft_record(ni);
                        /* Do we want the base record back? */
                        if (MREF_LE(al_entry->mft_reference) ==
                                        base_ni->mft_no) {
                                ni = ctx->ntfs_ino = base_ni;
                                ctx->mrec = ctx->base_mrec;
                                ctx->mapped_mrec = ctx->mapped_base_mrec;
                        } else {
                                /* We want an extent record. */
                                ctx->mrec = map_extent_mft_record(base_ni,
                                                le64_to_cpu(
                                                al_entry->mft_reference), &ni);
                                if (IS_ERR(ctx->mrec)) {
                                        ntfs_error(vol->sb,
                                                        "Failed to map extent mft record 0x%lx of base inode 0x%llx.%s",
                                                        MREF_LE(al_entry->mft_reference),
                                                        base_ni->mft_no, es);
                                        err = PTR_ERR(ctx->mrec);
                                        if (err == -ENOENT)
                                                err = -EIO;
                                        /* Cause @ctx to be sanitized below. */
                                        ni = NULL;
                                        break;
                                }
                                ctx->ntfs_ino = ni;
                                ctx->mapped_mrec = true;

                        }
                }
                a = ctx->attr = (struct attr_record *)((u8 *)ctx->mrec +
                                        le16_to_cpu(ctx->mrec->attrs_offset));
                /*
                 * ctx->vfs_ino, ctx->mrec, and ctx->attr now point to the
                 * mft record containing the attribute represented by the
                 * current al_entry.
                 */
                /*
                 * We could call into ntfs_attr_find() to find the right
                 * attribute in this mft record but this would be less
                 * efficient and not quite accurate as ntfs_attr_find() ignores
                 * the attribute instance numbers for example which become
                 * important when one plays with attribute lists.  Also,
                 * because a proper match has been found in the attribute list
                 * entry above, the comparison can now be optimized.  So it is
                 * worth re-implementing a simplified ntfs_attr_find() here.
                 */
                /*
                 * Use a manual loop so we can still use break and continue
                 * with the same meanings as above.
                 */
do_next_attr_loop:
                if ((u8 *)a < (u8 *)ctx->mrec ||
                    (u8 *)a >= (u8 *)ctx->mrec + le32_to_cpu(ctx->mrec->bytes_allocated) ||
                    (u8 *)a >= (u8 *)ctx->mrec + le32_to_cpu(ctx->mrec->bytes_in_use))
                        break;

                mft_free_len = le32_to_cpu(ctx->mrec->bytes_in_use) -
                               ((u8 *)a - (u8 *)ctx->mrec);
                if (mft_free_len >= sizeof(a->type) && a->type == AT_END)
                        continue;

                attr_len = le32_to_cpu(a->length);
                if (!attr_len ||
                    attr_len < offsetof(struct attr_record, data.resident.reserved) +
                    sizeof(a->data.resident.reserved) ||
                    attr_len > mft_free_len)
                        break;

                if (al_entry->instance != a->instance)
                        goto do_next_attr;
                /*
                 * If the type and/or the name are mismatched between the
                 * attribute list entry and the attribute record, there is
                 * corruption so we break and return error EIO.
                 */
                if (al_entry->type != a->type)
                        break;
                if (a->name_length && ((le16_to_cpu(a->name_offset) +
                               a->name_length * sizeof(__le16)) > attr_len))
                        break;
                if (!ntfs_are_names_equal((__le16 *)((u8 *)a +
                                le16_to_cpu(a->name_offset)), a->name_length,
                                al_name, al_name_len, CASE_SENSITIVE,
                                vol->upcase, vol->upcase_len))
                        break;

                ctx->attr = a;

                if (!ntfs_attr_value_is_valid(vol, a, ctx->ntfs_ino->mft_no))
                        break;

                /*
                 * If no @val specified or @val specified and it matches, we
                 * have found it!
                 */
                if ((type == AT_UNUSED) || !val)
                        goto attr_found;
                if (!a->non_resident) {
                        u32 value_length = le32_to_cpu(a->data.resident.value_length);
                        u16 value_offset = le16_to_cpu(a->data.resident.value_offset);

                        if (value_length == val_len &&
                            !memcmp((u8 *)a + value_offset, val, val_len)) {
attr_found:
                                ntfs_debug("Done, found.");
                                return 0;
                        }
                }
do_next_attr:
                /* Proceed to the next attribute in the current mft record. */
                a = (struct attr_record *)((u8 *)a + attr_len);
                goto do_next_attr_loop;
        }

corrupt:
        if (ni != base_ni) {
                if (ni)
                        unmap_extent_mft_record(ni);
                ctx->ntfs_ino = base_ni;
                ctx->mrec = ctx->base_mrec;
                ctx->attr = ctx->base_attr;
                ctx->mapped_mrec = ctx->mapped_base_mrec;
        }

        if (!err) {
                u64 mft_no = ctx->al_entry ? MREF_LE(ctx->al_entry->mft_reference) : 0;
                u32 type = ctx->al_entry ? le32_to_cpu(ctx->al_entry->type) : 0;

                ntfs_error(vol->sb,
                        "Base inode 0x%llx contains corrupt attribute, mft %#llx, type %#x. %s",
                        (long long)base_ni->mft_no, (long long)mft_no, type,
                        "Unmount and run chkdsk.");
                err = -EIO;
        }

        if (err != -ENOMEM)
                NVolSetErrors(vol);
        return err;
not_found:
        /*
         * If we were looking for AT_END, we reset the search context @ctx and
         * use ntfs_attr_find() to seek to the end of the base mft record.
         */
        if (type == AT_UNUSED || type == AT_END) {
                ntfs_attr_reinit_search_ctx(ctx);
                return ntfs_attr_find(AT_END, name, name_len, ic, val, val_len,
                                ctx);
        }
        /*
         * The attribute was not found.  Before we return, we want to ensure
         * @ctx->mrec and @ctx->attr indicate the position at which the
         * attribute should be inserted in the base mft record.  Since we also
         * want to preserve @ctx->al_entry we cannot reinitialize the search
         * context using ntfs_attr_reinit_search_ctx() as this would set
         * @ctx->al_entry to NULL.  Thus we do the necessary bits manually (see
         * ntfs_attr_init_search_ctx() below).  Note, we _only_ preserve
         * @ctx->al_entry as the remaining fields (base_*) are identical to
         * their non base_ counterparts and we cannot set @ctx->base_attr
         * correctly yet as we do not know what @ctx->attr will be set to by
         * the call to ntfs_attr_find() below.
         */
        if (ni != base_ni)
                unmap_extent_mft_record(ni);
        ctx->mrec = ctx->base_mrec;
        ctx->attr = (struct attr_record *)((u8 *)ctx->mrec +
                        le16_to_cpu(ctx->mrec->attrs_offset));
        ctx->is_first = true;
        ctx->ntfs_ino = base_ni;
        ctx->base_ntfs_ino = NULL;
        ctx->base_mrec = NULL;
        ctx->base_attr = NULL;
        ctx->mapped_mrec = ctx->mapped_base_mrec;
        /*
         * In case there are multiple matches in the base mft record, need to
         * keep enumerating until we get an attribute not found response (or
         * another error), otherwise we would keep returning the same attribute
         * over and over again and all programs using us for enumeration would
         * lock up in a tight loop.
         */
        do {
                err = ntfs_attr_find(type, name, name_len, ic, val, val_len,
                                ctx);
        } while (!err);
        ntfs_debug("Done, not found.");
        return err;
}

/*
 * ntfs_attr_lookup - find an attribute in an ntfs inode
 * @type:       attribute type to find
 * @name:       attribute name to find (optional, i.e. NULL means don't care)
 * @name_len:   attribute name length (only needed if @name present)
 * @ic:         IGNORE_CASE or CASE_SENSITIVE (ignored if @name not present)
 * @lowest_vcn: lowest vcn to find (optional, non-resident attributes only)
 * @val:        attribute value to find (optional, resident attributes only)
 * @val_len:    attribute value length
 * @ctx:        search context with mft record and attribute to search from
 *
 * Find an attribute in an ntfs inode.  On first search @ctx->ntfs_ino must
 * be the base mft record and @ctx must have been obtained from a call to
 * ntfs_attr_get_search_ctx().
 *
 * This function transparently handles attribute lists and @ctx is used to
 * continue searches where they were left off at.
 *
 * After finishing with the attribute/mft record you need to call
 * ntfs_attr_put_search_ctx() to cleanup the search context (unmapping any
 * mapped inodes, etc).
 *
 * Return 0 if the search was successful and -errno if not.
 *
 * When 0, @ctx->attr is the found attribute and it is in mft record
 * @ctx->mrec.  If an attribute list attribute is present, @ctx->al_entry is
 * the attribute list entry of the found attribute.
 *
 * When -ENOENT, @ctx->attr is the attribute which collates just after the
 * attribute being searched for, i.e. if one wants to add the attribute to the
 * mft record this is the correct place to insert it into.  If an attribute
 * list attribute is present, @ctx->al_entry is the attribute list entry which
 * collates just after the attribute list entry of the attribute being searched
 * for, i.e. if one wants to add the attribute to the mft record this is the
 * correct place to insert its attribute list entry into.
 */
int ntfs_attr_lookup(const __le32 type, const __le16 *name,
                const u32 name_len, const u32 ic,
                const s64 lowest_vcn, const u8 *val, const u32 val_len,
                struct ntfs_attr_search_ctx *ctx)
{
        struct ntfs_inode *base_ni;

        ntfs_debug("Entering.");
        if (ctx->base_ntfs_ino)
                base_ni = ctx->base_ntfs_ino;
        else
                base_ni = ctx->ntfs_ino;
        /* Sanity check, just for debugging really. */
        if (!base_ni || !NInoAttrList(base_ni) || type == AT_ATTRIBUTE_LIST)
                return ntfs_attr_find(type, name, name_len, ic, val, val_len,
                                ctx);
        return ntfs_external_attr_find(type, name, name_len, ic, lowest_vcn,
                        val, val_len, ctx);
}

/**
 * ntfs_attr_init_search_ctx - initialize an attribute search context
 * @ctx:        attribute search context to initialize
 * @ni:         ntfs inode with which to initialize the search context
 * @mrec:       mft record with which to initialize the search context
 *
 * Initialize the attribute search context @ctx with @ni and @mrec.
 */
static bool ntfs_attr_init_search_ctx(struct ntfs_attr_search_ctx *ctx,
                struct ntfs_inode *ni, struct mft_record *mrec)
{
        if (!mrec) {
                mrec = map_mft_record(ni);
                if (IS_ERR(mrec))
                        return false;
                ctx->mapped_mrec = true;
        } else {
                ctx->mapped_mrec = false;
        }

        ctx->mrec = mrec;
        /* Sanity checks are performed elsewhere. */
        ctx->attr = (struct attr_record *)((u8 *)mrec + le16_to_cpu(mrec->attrs_offset));
        ctx->is_first = true;
        ctx->ntfs_ino = ni;
        ctx->al_entry = NULL;
        ctx->base_ntfs_ino = NULL;
        ctx->base_mrec = NULL;
        ctx->base_attr = NULL;
        ctx->mapped_base_mrec = false;
        return true;
}

/*
 * ntfs_attr_reinit_search_ctx - reinitialize an attribute search context
 * @ctx:        attribute search context to reinitialize
 *
 * Reinitialize the attribute search context @ctx, unmapping an associated
 * extent mft record if present, and initialize the search context again.
 *
 * This is used when a search for a new attribute is being started to reset
 * the search context to the beginning.
 */
void ntfs_attr_reinit_search_ctx(struct ntfs_attr_search_ctx *ctx)
{
        bool mapped_mrec;

        if (likely(!ctx->base_ntfs_ino)) {
                /* No attribute list. */
                ctx->is_first = true;
                /* Sanity checks are performed elsewhere. */
                ctx->attr = (struct attr_record *)((u8 *)ctx->mrec +
                                le16_to_cpu(ctx->mrec->attrs_offset));
                /*
                 * This needs resetting due to ntfs_external_attr_find() which
                 * can leave it set despite having zeroed ctx->base_ntfs_ino.
                 */
                ctx->al_entry = NULL;
                return;
        } /* Attribute list. */
        if (ctx->ntfs_ino != ctx->base_ntfs_ino && ctx->ntfs_ino)
                unmap_extent_mft_record(ctx->ntfs_ino);

        mapped_mrec = ctx->mapped_base_mrec;
        ntfs_attr_init_search_ctx(ctx, ctx->base_ntfs_ino, ctx->base_mrec);
        ctx->mapped_mrec = mapped_mrec;
}

/*
 * ntfs_attr_get_search_ctx - allocate/initialize a new attribute search context
 * @ni:         ntfs inode with which to initialize the search context
 * @mrec:       mft record with which to initialize the search context
 *
 * Allocate a new attribute search context, initialize it with @ni and @mrec,
 * and return it. Return NULL if allocation failed.
 */
struct ntfs_attr_search_ctx *ntfs_attr_get_search_ctx(struct ntfs_inode *ni,
                struct mft_record *mrec)
{
        struct ntfs_attr_search_ctx *ctx;
        bool init;

        ctx = kmem_cache_alloc(ntfs_attr_ctx_cache, GFP_NOFS);
        if (ctx) {
                init = ntfs_attr_init_search_ctx(ctx, ni, mrec);
                if (init == false) {
                        kmem_cache_free(ntfs_attr_ctx_cache, ctx);
                        ctx = NULL;
                }
        }

        return ctx;
}

/*
 * ntfs_attr_put_search_ctx - release an attribute search context
 * @ctx:        attribute search context to free
 *
 * Release the attribute search context @ctx, unmapping an associated extent
 * mft record if present.
 */
void ntfs_attr_put_search_ctx(struct ntfs_attr_search_ctx *ctx)
{
        if (ctx->mapped_mrec)
                unmap_mft_record(ctx->ntfs_ino);

        if (ctx->mapped_base_mrec && ctx->base_ntfs_ino &&
            ctx->ntfs_ino != ctx->base_ntfs_ino)
                unmap_extent_mft_record(ctx->base_ntfs_ino);
        kmem_cache_free(ntfs_attr_ctx_cache, ctx);
}

/*
 * ntfs_attr_find_in_attrdef - find an attribute in the $AttrDef system file
 * @vol:        ntfs volume to which the attribute belongs
 * @type:       attribute type which to find
 *
 * Search for the attribute definition record corresponding to the attribute
 * @type in the $AttrDef system file.
 *
 * Return the attribute type definition record if found and NULL if not found.
 */
static struct attr_def *ntfs_attr_find_in_attrdef(const struct ntfs_volume *vol,
                const __le32 type)
{
        struct attr_def *ad;

        WARN_ON(!type);
        for (ad = vol->attrdef; (u8 *)ad - (u8 *)vol->attrdef <
                        vol->attrdef_size && ad->type; ++ad) {
                /* We have not found it yet, carry on searching. */
                if (likely(le32_to_cpu(ad->type) < le32_to_cpu(type)))
                        continue;
                /* We found the attribute; return it. */
                if (likely(ad->type == type))
                        return ad;
                /* We have gone too far already.  No point in continuing. */
                break;
        }
        /* Attribute not found. */
        ntfs_debug("Attribute type 0x%x not found in $AttrDef.",
                        le32_to_cpu(type));
        return NULL;
}

/*
 * ntfs_attr_size_bounds_check - check a size of an attribute type for validity
 * @vol:        ntfs volume to which the attribute belongs
 * @type:       attribute type which to check
 * @size:       size which to check
 *
 * Check whether the @size in bytes is valid for an attribute of @type on the
 * ntfs volume @vol.  This information is obtained from $AttrDef system file.
 */
int ntfs_attr_size_bounds_check(const struct ntfs_volume *vol, const __le32 type,
                const s64 size)
{
        struct attr_def *ad;

        if (size < 0)
                return -EINVAL;

        /*
         * $ATTRIBUTE_LIST has a maximum size of 256kiB, but this is not
         * listed in $AttrDef.
         */
        if (unlikely(type == AT_ATTRIBUTE_LIST && size > 256 * 1024))
                return -ERANGE;
        /* Get the $AttrDef entry for the attribute @type. */
        ad = ntfs_attr_find_in_attrdef(vol, type);
        if (unlikely(!ad))
                return -ENOENT;
        /* Do the bounds check. */
        if (((le64_to_cpu(ad->min_size) > 0) &&
                        size < le64_to_cpu(ad->min_size)) ||
                        ((le64_to_cpu(ad->max_size) > 0) && size >
                        le64_to_cpu(ad->max_size)))
                return -ERANGE;
        return 0;
}

/*
 * ntfs_attr_can_be_non_resident - check if an attribute can be non-resident
 * @vol:        ntfs volume to which the attribute belongs
 * @type:       attribute type which to check
 *
 * Check whether the attribute of @type on the ntfs volume @vol is allowed to
 * be non-resident.  This information is obtained from $AttrDef system file.
 */
static int ntfs_attr_can_be_non_resident(const struct ntfs_volume *vol,
                const __le32 type)
{
        struct attr_def *ad;

        /* Find the attribute definition record in $AttrDef. */
        ad = ntfs_attr_find_in_attrdef(vol, type);
        if (unlikely(!ad))
                return -ENOENT;
        /* Check the flags and return the result. */
        if (ad->flags & ATTR_DEF_RESIDENT)
                return -EPERM;
        return 0;
}

/*
 * ntfs_attr_can_be_resident - check if an attribute can be resident
 * @vol:        ntfs volume to which the attribute belongs
 * @type:       attribute type which to check
 *
 * Check whether the attribute of @type on the ntfs volume @vol is allowed to
 * be resident.  This information is derived from our ntfs knowledge and may
 * not be completely accurate, especially when user defined attributes are
 * present.  Basically we allow everything to be resident except for index
 * allocation and $EA attributes.
 *
 * Return 0 if the attribute is allowed to be non-resident and -EPERM if not.
 *
 * Warning: In the system file $MFT the attribute $Bitmap must be non-resident
 *          otherwise windows will not boot (blue screen of death)!  We cannot
 *          check for this here as we do not know which inode's $Bitmap is
 *          being asked about so the caller needs to special case this.
 */
int ntfs_attr_can_be_resident(const struct ntfs_volume *vol, const __le32 type)
{
        if (type == AT_INDEX_ALLOCATION)
                return -EPERM;
        return 0;
}

/*
 * ntfs_attr_record_resize - resize an attribute record
 * @m:          mft record containing attribute record
 * @a:          attribute record to resize
 * @new_size:   new size in bytes to which to resize the attribute record @a
 *
 * Resize the attribute record @a, i.e. the resident part of the attribute, in
 * the mft record @m to @new_size bytes.
 */
int ntfs_attr_record_resize(struct mft_record *m, struct attr_record *a, u32 new_size)
{
        u32 old_size, alloc_size, attr_size;

        old_size   = le32_to_cpu(m->bytes_in_use);
        alloc_size = le32_to_cpu(m->bytes_allocated);
        attr_size  = le32_to_cpu(a->length);

        ntfs_debug("Sizes: old=%u alloc=%u attr=%u new=%u\n",
                        (unsigned int)old_size, (unsigned int)alloc_size,
                        (unsigned int)attr_size, (unsigned int)new_size);

        /* Align to 8 bytes if it is not already done. */
        if (new_size & 7)
                new_size = (new_size + 7) & ~7;
        /* If the actual attribute length has changed, move things around. */
        if (new_size != attr_size) {
                u32 new_muse = le32_to_cpu(m->bytes_in_use) -
                                attr_size + new_size;
                /* Not enough space in this mft record. */
                if (new_muse > le32_to_cpu(m->bytes_allocated))
                        return -ENOSPC;

                if (a->type == AT_INDEX_ROOT && new_size > attr_size &&
                        new_muse + 120 > alloc_size && old_size + 120 <= alloc_size) {
                        ntfs_debug("Too big struct index_root (%u > %u)\n",
                                        new_muse, alloc_size);
                        return -ENOSPC;
                }

                /* Move attributes following @a to their new location. */
                memmove((u8 *)a + new_size, (u8 *)a + le32_to_cpu(a->length),
                                le32_to_cpu(m->bytes_in_use) - ((u8 *)a -
                                (u8 *)m) - attr_size);
                /* Adjust @m to reflect the change in used space. */
                m->bytes_in_use = cpu_to_le32(new_muse);
                /* Adjust @a to reflect the new size. */
                if (new_size >= offsetof(struct attr_record, length) + sizeof(a->length))
                        a->length = cpu_to_le32(new_size);
        }
        return 0;
}

/*
 * ntfs_resident_attr_value_resize - resize the value of a resident attribute
 * @m:          mft record containing attribute record
 * @a:          attribute record whose value to resize
 * @new_size:   new size in bytes to which to resize the attribute value of @a
 *
 * Resize the value of the attribute @a in the mft record @m to @new_size bytes.
 * If the value is made bigger, the newly allocated space is cleared.
 */
int ntfs_resident_attr_value_resize(struct mft_record *m, struct attr_record *a,
                const u32 new_size)
{
        u32 old_size;

        /* Resize the resident part of the attribute record. */
        if (ntfs_attr_record_resize(m, a,
                        le16_to_cpu(a->data.resident.value_offset) + new_size))
                return -ENOSPC;
        /*
         * The resize succeeded!  If we made the attribute value bigger, clear
         * the area between the old size and @new_size.
         */
        old_size = le32_to_cpu(a->data.resident.value_length);
        if (new_size > old_size)
                memset((u8 *)a + le16_to_cpu(a->data.resident.value_offset) +
                                old_size, 0, new_size - old_size);
        /* Finally update the length of the attribute value. */
        a->data.resident.value_length = cpu_to_le32(new_size);
        return 0;
}

/*
 * ntfs_attr_make_non_resident - convert a resident to a non-resident attribute
 * @ni:         ntfs inode describing the attribute to convert
 * @data_size:  size of the resident data to copy to the non-resident attribute
 *
 * Convert the resident ntfs attribute described by the ntfs inode @ni to a
 * non-resident one.
 *
 * @data_size must be equal to the attribute value size.  This is needed since
 * we need to know the size before we can map the mft record and our callers
 * always know it.  The reason we cannot simply read the size from the vfs
 * inode i_size is that this is not necessarily uptodate.  This happens when
 * ntfs_attr_make_non_resident() is called in the ->truncate call path(s).
 */
int ntfs_attr_make_non_resident(struct ntfs_inode *ni, const u32 data_size)
{
        s64 new_size;
        struct inode *vi = VFS_I(ni);
        struct ntfs_volume *vol = ni->vol;
        struct ntfs_inode *base_ni;
        struct mft_record *m;
        struct attr_record *a;
        struct ntfs_attr_search_ctx *ctx;
        struct folio *folio;
        struct runlist_element *rl;
        unsigned long flags;
        int mp_size, mp_ofs, name_ofs, arec_size, err, err2;
        u32 attr_size;
        u8 old_res_attr_flags;

        if (NInoNonResident(ni)) {
                ntfs_warning(vol->sb,
                        "Trying to make non-resident attribute non-resident.  Aborting...\n");
                return -EINVAL;
        }

        /* Check that the attribute is allowed to be non-resident. */
        err = ntfs_attr_can_be_non_resident(vol, ni->type);
        if (unlikely(err)) {
                if (err == -EPERM)
                        ntfs_debug("Attribute is not allowed to be non-resident.");
                else
                        ntfs_debug("Attribute not defined on the NTFS volume!");
                return err;
        }

        if (NInoEncrypted(ni))
                return -EIO;

        if (!NInoAttr(ni))
                base_ni = ni;
        else
                base_ni = ni->ext.base_ntfs_ino;
        m = map_mft_record(base_ni);
        if (IS_ERR(m)) {
                err = PTR_ERR(m);
                m = NULL;
                ctx = NULL;
                goto err_out;
        }
        ctx = ntfs_attr_get_search_ctx(base_ni, m);
        if (unlikely(!ctx)) {
                err = -ENOMEM;
                goto err_out;
        }
        err = ntfs_attr_lookup(ni->type, ni->name, ni->name_len,
                        CASE_SENSITIVE, 0, NULL, 0, ctx);
        if (unlikely(err)) {
                if (err == -ENOENT)
                        err = -EIO;
                goto err_out;
        }
        m = ctx->mrec;
        a = ctx->attr;

        /*
         * The size needs to be aligned to a cluster boundary for allocation
         * purposes.
         */
        new_size = (data_size + vol->cluster_size - 1) &
                        ~(vol->cluster_size - 1);
        if (new_size > 0) {
                if ((a->flags & ATTR_COMPRESSION_MASK) == ATTR_IS_COMPRESSED) {
                        /* must allocate full compression blocks */
                        new_size =
                                ((new_size - 1) |
                                 ((1L << (STANDARD_COMPRESSION_UNIT +
                                          vol->cluster_size_bits)) - 1)) + 1;
                }

                /*
                 * Will need folio later and since folio lock nests
                 * outside all ntfs locks, we need to get the folio now.
                 */
                folio = __filemap_get_folio(vi->i_mapping, 0,
                                            FGP_CREAT | FGP_LOCK,
                                            mapping_gfp_mask(vi->i_mapping));
                if (IS_ERR(folio)) {
                        err = -ENOMEM;
                        goto err_out;
                }

                /* Start by allocating clusters to hold the attribute value. */
                rl = ntfs_cluster_alloc(vol, 0,
                                ntfs_bytes_to_cluster(vol, new_size),
                                -1, DATA_ZONE, true, false, false);
                if (IS_ERR(rl)) {
                        err = PTR_ERR(rl);
                        ntfs_debug("Failed to allocate cluster%s, error code %i.",
                                        str_plural(ntfs_bytes_to_cluster(vol, new_size)),
                                        err);
                        goto folio_err_out;
                }
        } else {
                rl = NULL;
                folio = NULL;
        }

        down_write(&ni->runlist.lock);
        /* Determine the size of the mapping pairs array. */
        mp_size = ntfs_get_size_for_mapping_pairs(vol, rl, 0, -1, -1);
        if (unlikely(mp_size < 0)) {
                err = mp_size;
                ntfs_debug("Failed to get size for mapping pairs array, error code %i.\n", err);
                goto rl_err_out;
        }

        if (NInoNonResident(ni) || a->non_resident) {
                err = -EIO;
                goto rl_err_out;
        }

        /*
         * Calculate new offsets for the name and the mapping pairs array.
         */
        if (NInoSparse(ni) || NInoCompressed(ni))
                name_ofs = (offsetof(struct attr_record,
                                data.non_resident.compressed_size) +
                                sizeof(a->data.non_resident.compressed_size) +
                                7) & ~7;
        else
                name_ofs = (offsetof(struct attr_record,
                                data.non_resident.compressed_size) + 7) & ~7;
        mp_ofs = (name_ofs + a->name_length * sizeof(__le16) + 7) & ~7;
        /*
         * Determine the size of the resident part of the now non-resident
         * attribute record.
         */
        arec_size = (mp_ofs + mp_size + 7) & ~7;
        /*
         * If the folio is not uptodate bring it uptodate by copying from the
         * attribute value.
         */
        attr_size = le32_to_cpu(a->data.resident.value_length);
        WARN_ON(attr_size != data_size);
        if (folio && !folio_test_uptodate(folio)) {
                folio_fill_tail(folio, 0, (u8 *)a +
                                le16_to_cpu(a->data.resident.value_offset),
                                attr_size);
                folio_mark_uptodate(folio);
        }

        /* Backup the attribute flag. */
        old_res_attr_flags = a->data.resident.flags;
        /* Resize the resident part of the attribute record. */
        err = ntfs_attr_record_resize(m, a, arec_size);
        if (unlikely(err))
                goto rl_err_out;

        /*
         * Convert the resident part of the attribute record to describe a
         * non-resident attribute.
         */
        a->non_resident = 1;
        /* Move the attribute name if it exists and update the offset. */
        if (a->name_length)
                memmove((u8 *)a + name_ofs, (u8 *)a + le16_to_cpu(a->name_offset),
                                a->name_length * sizeof(__le16));
        a->name_offset = cpu_to_le16(name_ofs);
        /* Setup the fields specific to non-resident attributes. */
        a->data.non_resident.lowest_vcn = 0;
        a->data.non_resident.highest_vcn =
                cpu_to_le64(ntfs_bytes_to_cluster(vol, new_size - 1));
        a->data.non_resident.mapping_pairs_offset = cpu_to_le16(mp_ofs);
        memset(&a->data.non_resident.reserved, 0,
                        sizeof(a->data.non_resident.reserved));
        a->data.non_resident.allocated_size = cpu_to_le64(new_size);
        a->data.non_resident.data_size =
                        a->data.non_resident.initialized_size =
                        cpu_to_le64(attr_size);
        if (NInoSparse(ni) || NInoCompressed(ni)) {
                a->data.non_resident.compression_unit = 0;
                if (NInoCompressed(ni) || vol->major_ver < 3)
                        a->data.non_resident.compression_unit = 4;
                a->data.non_resident.compressed_size =
                                a->data.non_resident.allocated_size;
        } else
                a->data.non_resident.compression_unit = 0;
        /* Generate the mapping pairs array into the attribute record. */
        err = ntfs_mapping_pairs_build(vol, (u8 *)a + mp_ofs,
                        arec_size - mp_ofs, rl, 0, -1, NULL, NULL, NULL);
        if (unlikely(err)) {
                ntfs_error(vol->sb, "Failed to build mapping pairs, error code %i.",
                                err);
                goto undo_err_out;
        }

        /* Setup the in-memory attribute structure to be non-resident. */
        ni->runlist.rl = rl;
        if (rl) {
                for (ni->runlist.count = 1; rl->length != 0; rl++)
                        ni->runlist.count++;
        } else
                ni->runlist.count = 0;
        write_lock_irqsave(&ni->size_lock, flags);
        ni->allocated_size = new_size;
        if (NInoSparse(ni) || NInoCompressed(ni)) {
                ni->itype.compressed.size = ni->allocated_size;
                if (a->data.non_resident.compression_unit) {
                        ni->itype.compressed.block_size = 1U <<
                                (a->data.non_resident.compression_unit +
                                 vol->cluster_size_bits);
                        ni->itype.compressed.block_size_bits =
                                        ffs(ni->itype.compressed.block_size) -
                                        1;
                        ni->itype.compressed.block_clusters = 1U <<
                                        a->data.non_resident.compression_unit;
                } else {
                        ni->itype.compressed.block_size = 0;
                        ni->itype.compressed.block_size_bits = 0;
                        ni->itype.compressed.block_clusters = 0;
                }
                vi->i_blocks = ni->itype.compressed.size >> 9;
        } else
                vi->i_blocks = ni->allocated_size >> 9;
        write_unlock_irqrestore(&ni->size_lock, flags);
        /*
         * This needs to be last since the address space operations ->read_folio
         * and ->writepage can run concurrently with us as they are not
         * serialized on i_mutex.  Note, we are not allowed to fail once we flip
         * this switch, which is another reason to do this last.
         */
        NInoSetNonResident(ni);
        NInoSetFullyMapped(ni);
        /* Mark the mft record dirty, so it gets written back. */
        mark_mft_record_dirty(ctx->ntfs_ino);
        ntfs_attr_put_search_ctx(ctx);
        unmap_mft_record(base_ni);
        up_write(&ni->runlist.lock);
        if (folio) {
                iomap_dirty_folio(vi->i_mapping, folio);
                folio_unlock(folio);
                folio_put(folio);
        }
        ntfs_debug("Done.");
        return 0;
undo_err_out:
        /* Convert the attribute back into a resident attribute. */
        a->non_resident = 0;
        /* Move the attribute name if it exists and update the offset. */
        name_ofs = (offsetof(struct attr_record, data.resident.reserved) +
                        sizeof(a->data.resident.reserved) + 7) & ~7;
        if (a->name_length)
                memmove((u8 *)a + name_ofs, (u8 *)a + le16_to_cpu(a->name_offset),
                                a->name_length * sizeof(__le16));
        mp_ofs = (name_ofs + a->name_length * sizeof(__le16) + 7) & ~7;
        a->name_offset = cpu_to_le16(name_ofs);
        arec_size = (mp_ofs + attr_size + 7) & ~7;
        /* Resize the resident part of the attribute record. */
        err2 = ntfs_attr_record_resize(m, a, arec_size);
        if (unlikely(err2)) {
                /*
                 * This cannot happen (well if memory corruption is at work it
                 * could happen in theory), but deal with it as well as we can.
                 * If the old size is too small, truncate the attribute,
                 * otherwise simply give it a larger allocated size.
                 */
                arec_size = le32_to_cpu(a->length);
                if ((mp_ofs + attr_size) > arec_size) {
                        err2 = attr_size;
                        attr_size = arec_size - mp_ofs;
                        ntfs_error(vol->sb,
                                "Failed to undo partial resident to non-resident attribute conversion.  Truncating inode 0x%llx, attribute type 0x%x from %i bytes to %i bytes to maintain metadata consistency.  THIS MEANS YOU ARE LOSING %i BYTES DATA FROM THIS %s.",
                                        ni->mft_no,
                                        (unsigned int)le32_to_cpu(ni->type),
                                        err2, attr_size, err2 - attr_size,
                                        ((ni->type == AT_DATA) &&
                                        !ni->name_len) ? "FILE" : "ATTRIBUTE");
                        write_lock_irqsave(&ni->size_lock, flags);
                        ni->initialized_size = attr_size;
                        i_size_write(vi, attr_size);
                        write_unlock_irqrestore(&ni->size_lock, flags);
                }
        }
        /* Setup the fields specific to resident attributes. */
        a->data.resident.value_length = cpu_to_le32(attr_size);
        a->data.resident.value_offset = cpu_to_le16(mp_ofs);
        a->data.resident.flags = old_res_attr_flags;
        memset(&a->data.resident.reserved, 0,
                        sizeof(a->data.resident.reserved));
        /* Copy the data from folio back to the attribute value. */
        if (folio)
                memcpy_from_folio((u8 *)a + mp_ofs, folio, 0, attr_size);
        /* Setup the allocated size in the ntfs inode in case it changed. */
        write_lock_irqsave(&ni->size_lock, flags);
        ni->allocated_size = arec_size - mp_ofs;
        write_unlock_irqrestore(&ni->size_lock, flags);
        /* Mark the mft record dirty, so it gets written back. */
        mark_mft_record_dirty(ctx->ntfs_ino);
rl_err_out:
        up_write(&ni->runlist.lock);
        if (rl) {
                if (ntfs_cluster_free_from_rl(vol, rl) < 0) {
                        ntfs_error(vol->sb,
                                "Failed to release allocated cluster(s) in error code path.  Run chkdsk to recover the lost cluster(s).");
                        NVolSetErrors(vol);
                }
                kvfree(rl);
folio_err_out:
                folio_unlock(folio);
                folio_put(folio);
        }
err_out:
        if (ctx)
                ntfs_attr_put_search_ctx(ctx);
        if (m)
                unmap_mft_record(base_ni);
        ni->runlist.rl = NULL;

        if (err == -EINVAL)
                err = -EIO;
        return err;
}

/*
 * ntfs_attr_set - fill (a part of) an attribute with a byte
 * @ni:         ntfs inode describing the attribute to fill
 * @ofs:        offset inside the attribute at which to start to fill
 * @cnt:        number of bytes to fill
 * @val:        the unsigned 8-bit value with which to fill the attribute
 *
 * Fill @cnt bytes of the attribute described by the ntfs inode @ni starting at
 * byte offset @ofs inside the attribute with the constant byte @val.
 *
 * This function is effectively like memset() applied to an ntfs attribute.
 * Note thie function actually only operates on the page cache pages belonging
 * to the ntfs attribute and it marks them dirty after doing the memset().
 * Thus it relies on the vm dirty page write code paths to cause the modified
 * pages to be written to the mft record/disk.
 */
int ntfs_attr_set(struct ntfs_inode *ni, s64 ofs, s64 cnt, const u8 val)
{
        struct address_space *mapping = VFS_I(ni)->i_mapping;
        struct folio *folio;
        pgoff_t index;
        u8 *addr;
        unsigned long offset;
        size_t attr_len;
        int ret = 0;

        index = ofs >> PAGE_SHIFT;
        while (cnt) {
                folio = read_mapping_folio(mapping, index, NULL);
                if (IS_ERR(folio)) {
                        ret = PTR_ERR(folio);
                        ntfs_error(VFS_I(ni)->i_sb, "Failed to read a page %lu for attr %#x: %ld",
                                   index, ni->type, PTR_ERR(folio));
                        break;
                }

                offset = offset_in_folio(folio, ofs);
                attr_len = min_t(size_t, (size_t)cnt, folio_size(folio) - offset);

                folio_lock(folio);
                addr = kmap_local_folio(folio, offset);
                memset(addr, val, attr_len);
                kunmap_local(addr);

                folio_mark_dirty(folio);
                folio_unlock(folio);
                folio_put(folio);

                ofs += attr_len;
                cnt -= attr_len;
                index++;
                cond_resched();
        }

        return ret;
}

int ntfs_attr_set_initialized_size(struct ntfs_inode *ni, loff_t new_size)
{
        struct ntfs_attr_search_ctx *ctx;
        int err = 0;

        if (!NInoNonResident(ni))
                return -EINVAL;

        ctx = ntfs_attr_get_search_ctx(ni, NULL);
        if (!ctx)
                return -ENOMEM;

        err = ntfs_attr_lookup(ni->type, ni->name, ni->name_len,
                               CASE_SENSITIVE, 0, NULL, 0, ctx);
        if (err)
                goto out_ctx;

        ctx->attr->data.non_resident.initialized_size = cpu_to_le64(new_size);
        ni->initialized_size = new_size;
        mark_mft_record_dirty(ctx->ntfs_ino);
out_ctx:
        ntfs_attr_put_search_ctx(ctx);
        return err;
}

/*
 * ntfs_make_room_for_attr - make room for an attribute inside an mft record
 * @m:          mft record
 * @pos:        position at which to make space
 * @size:       byte size to make available at this position
 *
 * @pos points to the attribute in front of which we want to make space.
 */
static int ntfs_make_room_for_attr(struct mft_record *m, u8 *pos, u32 size)
{
        u32 biu;

        ntfs_debug("Entering for pos 0x%x, size %u.\n",
                        (int)(pos - (u8 *)m), (unsigned int) size);

        /* Make size 8-byte alignment. */
        size = (size + 7) & ~7;

        /* Rigorous consistency checks. */
        if (!m || !pos || pos < (u8 *)m) {
                pr_err("%s: pos=%p  m=%p\n", __func__, pos, m);
                return -EINVAL;
        }

        /* The -8 is for the attribute terminator. */
        if (pos - (u8 *)m > (int)le32_to_cpu(m->bytes_in_use) - 8)
                return -EINVAL;
        /* Nothing to do. */
        if (!size)
                return 0;

        biu = le32_to_cpu(m->bytes_in_use);
        /* Do we have enough space? */
        if (biu + size > le32_to_cpu(m->bytes_allocated) ||
            pos + size > (u8 *)m + le32_to_cpu(m->bytes_allocated)) {
                ntfs_debug("No enough space in the MFT record\n");
                return -ENOSPC;
        }
        /* Move everything after pos to pos + size. */
        memmove(pos + size, pos, biu - (pos - (u8 *)m));
        /* Update mft record. */
        m->bytes_in_use = cpu_to_le32(biu + size);
        return 0;
}

/*
 * ntfs_resident_attr_record_add - add resident attribute to inode
 * @ni:         opened ntfs inode to which MFT record add attribute
 * @type:       type of the new attribute
 * @name:       name of the new attribute
 * @name_len:   name length of the new attribute
 * @val:        value of the new attribute
 * @size:       size of new attribute (length of @val, if @val != NULL)
 * @flags:      flags of the new attribute
 */
int ntfs_resident_attr_record_add(struct ntfs_inode *ni, __le32 type,
                __le16 *name, u8 name_len, u8 *val, u32 size,
                __le16 flags)
{
        struct ntfs_attr_search_ctx *ctx;
        u32 length;
        struct attr_record *a;
        struct mft_record *m;
        int err, offset;
        struct ntfs_inode *base_ni;

        if (!ni || (!name && name_len))
                return -EINVAL;

        ntfs_debug("Entering for inode 0x%llx, attr 0x%x, flags 0x%x.\n",
                        (long long) ni->mft_no, (unsigned int) le32_to_cpu(type),
                        (unsigned int) le16_to_cpu(flags));

        err = ntfs_attr_can_be_resident(ni->vol, type);
        if (err) {
                if (err == -EPERM)
                        ntfs_debug("Attribute can't be resident.\n");
                else
                        ntfs_debug("ntfs_attr_can_be_resident failed.\n");
                return err;
        }

        /* Locate place where record should be. */
        ctx = ntfs_attr_get_search_ctx(ni, NULL);
        if (!ctx) {
                ntfs_error(ni->vol->sb, "%s: Failed to get search context",
                                __func__);
                return -ENOMEM;
        }
        /*
         * Use ntfs_attr_find instead of ntfs_attr_lookup to find place for
         * attribute in @ni->mrec, not any extent inode in case if @ni is base
         * file record.
         */
        err = ntfs_attr_find(type, name, name_len, CASE_SENSITIVE, val, size, ctx);
        if (!err) {
                err = -EEXIST;
                ntfs_debug("Attribute already present.\n");
                goto put_err_out;
        }
        if (err != -ENOENT) {
                err = -EIO;
                goto put_err_out;
        }
        a = ctx->attr;
        m = ctx->mrec;

        /* Make room for attribute. */
        length = offsetof(struct attr_record, data.resident.reserved) +
                          sizeof(a->data.resident.reserved) +
                ((name_len * sizeof(__le16) + 7) & ~7) +
                ((size + 7) & ~7);
        err = ntfs_make_room_for_attr(ctx->mrec, (u8 *) ctx->attr, length);
        if (err) {
                ntfs_debug("Failed to make room for attribute.\n");
                goto put_err_out;
        }

        /* Setup record fields. */
        offset = ((u8 *)a - (u8 *)m);
        a->type = type;
        a->length = cpu_to_le32(length);
        a->non_resident = 0;
        a->name_length = name_len;
        a->name_offset =
                name_len ? cpu_to_le16((offsetof(struct attr_record, data.resident.reserved) +
                                sizeof(a->data.resident.reserved))) : cpu_to_le16(0);

        a->flags = flags;
        a->instance = m->next_attr_instance;
        a->data.resident.value_length = cpu_to_le32(size);
        a->data.resident.value_offset = cpu_to_le16(length - ((size + 7) & ~7));
        if (val)
                memcpy((u8 *)a + le16_to_cpu(a->data.resident.value_offset), val, size);
        else
                memset((u8 *)a + le16_to_cpu(a->data.resident.value_offset), 0, size);
        if (type == AT_FILE_NAME)
                a->data.resident.flags = RESIDENT_ATTR_IS_INDEXED;
        else
                a->data.resident.flags = 0;
        if (name_len)
                memcpy((u8 *)a + le16_to_cpu(a->name_offset),
                                name, sizeof(__le16) * name_len);
        m->next_attr_instance =
                cpu_to_le16((le16_to_cpu(m->next_attr_instance) + 1) & 0xffff);
        if (ni->nr_extents == -1)
                base_ni = ni->ext.base_ntfs_ino;
        else
                base_ni = ni;
        if (type != AT_ATTRIBUTE_LIST && NInoAttrList(base_ni)) {
                err = ntfs_attrlist_entry_add(ni, a);
                if (err) {
                        ntfs_attr_record_resize(m, a, 0);
                        mark_mft_record_dirty(ctx->ntfs_ino);
                        ntfs_debug("Failed add attribute entry to ATTRIBUTE_LIST.\n");
                        goto put_err_out;
                }
        }
        mark_mft_record_dirty(ni);
        ntfs_attr_put_search_ctx(ctx);
        return offset;
put_err_out:
        ntfs_attr_put_search_ctx(ctx);
        return -EIO;
}

/*
 * ntfs_non_resident_attr_record_add - add extent of non-resident attribute
 * @ni:                 opened ntfs inode to which MFT record add attribute
 * @type:               type of the new attribute extent
 * @name:               name of the new attribute extent
 * @name_len:           name length of the new attribute extent
 * @lowest_vcn:         lowest vcn of the new attribute extent
 * @dataruns_size:      dataruns size of the new attribute extent
 * @flags:              flags of the new attribute extent
 */
static int ntfs_non_resident_attr_record_add(struct ntfs_inode *ni, __le32 type,
                __le16 *name, u8 name_len, s64 lowest_vcn, int dataruns_size,
                __le16 flags)
{
        struct ntfs_attr_search_ctx *ctx;
        u32 length;
        struct attr_record *a;
        struct mft_record *m;
        struct ntfs_inode *base_ni;
        int err, offset;

        if (!ni || dataruns_size <= 0 || (!name && name_len))
                return -EINVAL;

        ntfs_debug("Entering for inode 0x%llx, attr 0x%x, lowest_vcn %lld, dataruns_size %d, flags 0x%x.\n",
                        (long long) ni->mft_no, (unsigned int) le32_to_cpu(type),
                        (long long) lowest_vcn, dataruns_size,
                        (unsigned int) le16_to_cpu(flags));

        err = ntfs_attr_can_be_non_resident(ni->vol, type);
        if (err) {
                if (err == -EPERM)
                        pr_err("Attribute can't be non resident\n");
                else
                        pr_err("ntfs_attr_can_be_non_resident failed\n");
                return err;
        }

        /* Locate place where record should be. */
        ctx = ntfs_attr_get_search_ctx(ni, NULL);
        if (!ctx) {
                pr_err("%s: Failed to get search context\n", __func__);
                return -ENOMEM;
        }
        /*
         * Use ntfs_attr_find instead of ntfs_attr_lookup to find place for
         * attribute in @ni->mrec, not any extent inode in case if @ni is base
         * file record.
         */
        err = ntfs_attr_find(type, name, name_len, CASE_SENSITIVE, NULL, 0, ctx);
        if (!err) {
                err = -EEXIST;
                pr_err("Attribute 0x%x already present\n", type);
                goto put_err_out;
        }
        if (err != -ENOENT) {
                pr_err("ntfs_attr_find failed\n");
                err = -EIO;
                goto put_err_out;
        }
        a = ctx->attr;
        m = ctx->mrec;

        /* Make room for attribute. */
        dataruns_size = (dataruns_size + 7) & ~7;
        length = offsetof(struct attr_record, data.non_resident.compressed_size) +
                ((sizeof(__le16) * name_len + 7) & ~7) + dataruns_size +
                ((flags & (ATTR_IS_COMPRESSED | ATTR_IS_SPARSE)) ?
                 sizeof(a->data.non_resident.compressed_size) : 0);
        err = ntfs_make_room_for_attr(ctx->mrec, (u8 *) ctx->attr, length);
        if (err) {
                pr_err("Failed to make room for attribute\n");
                goto put_err_out;
        }

        /* Setup record fields. */
        a->type = type;
        a->length = cpu_to_le32(length);
        a->non_resident = 1;
        a->name_length = name_len;
        a->name_offset = cpu_to_le16(offsetof(struct attr_record,
                                              data.non_resident.compressed_size) +
                        ((flags & (ATTR_IS_COMPRESSED | ATTR_IS_SPARSE)) ?
                         sizeof(a->data.non_resident.compressed_size) : 0));
        a->flags = flags;
        a->instance = m->next_attr_instance;
        a->data.non_resident.lowest_vcn = cpu_to_le64(lowest_vcn);
        a->data.non_resident.mapping_pairs_offset = cpu_to_le16(length - dataruns_size);
        a->data.non_resident.compression_unit =
                (flags & ATTR_IS_COMPRESSED) ? STANDARD_COMPRESSION_UNIT : 0;
        /* If @lowest_vcn == 0, than setup empty attribute. */
        if (!lowest_vcn) {
                a->data.non_resident.highest_vcn = cpu_to_le64(-1);
                a->data.non_resident.allocated_size = 0;
                a->data.non_resident.data_size = 0;
                a->data.non_resident.initialized_size = 0;
                /* Set empty mapping pairs. */
                *((u8 *)a + le16_to_cpu(a->data.non_resident.mapping_pairs_offset)) = 0;
        }
        if (name_len)
                memcpy((u8 *)a + le16_to_cpu(a->name_offset),
                                name, sizeof(__le16) * name_len);
        m->next_attr_instance =
                cpu_to_le16((le16_to_cpu(m->next_attr_instance) + 1) & 0xffff);
        if (ni->nr_extents == -1)
                base_ni = ni->ext.base_ntfs_ino;
        else
                base_ni = ni;
        if (type != AT_ATTRIBUTE_LIST && NInoAttrList(base_ni)) {
                err = ntfs_attrlist_entry_add(ni, a);
                if (err) {
                        pr_err("Failed add attr entry to attrlist\n");
                        ntfs_attr_record_resize(m, a, 0);
                        goto put_err_out;
                }
        }
        mark_mft_record_dirty(ni);
        /*
         * Locate offset from start of the MFT record where new attribute is
         * placed. We need relookup it, because record maybe moved during
         * update of attribute list.
         */
        ntfs_attr_reinit_search_ctx(ctx);
        err = ntfs_attr_lookup(type, name, name_len, CASE_SENSITIVE,
                                lowest_vcn, NULL, 0, ctx);
        if (err) {
                pr_err("%s: attribute lookup failed\n", __func__);
                ntfs_attr_put_search_ctx(ctx);
                return err;

        }
        offset = (u8 *)ctx->attr - (u8 *)ctx->mrec;
        ntfs_attr_put_search_ctx(ctx);
        return offset;
put_err_out:
        ntfs_attr_put_search_ctx(ctx);
        return -1;
}

/*
 * ntfs_attr_record_rm - remove attribute extent
 * @ctx:        search context describing the attribute which should be removed
 *
 * If this function succeed, user should reinit search context if he/she wants
 * use it anymore.
 */
int ntfs_attr_record_rm(struct ntfs_attr_search_ctx *ctx)
{
        struct ntfs_inode *base_ni, *ni;
        __le32 type;
        int err;

        if (!ctx || !ctx->ntfs_ino || !ctx->mrec || !ctx->attr)
                return -EINVAL;

        ntfs_debug("Entering for inode 0x%llx, attr 0x%x.\n",
                        (long long) ctx->ntfs_ino->mft_no,
                        (unsigned int) le32_to_cpu(ctx->attr->type));
        type = ctx->attr->type;
        ni = ctx->ntfs_ino;
        if (ctx->base_ntfs_ino)
                base_ni = ctx->base_ntfs_ino;
        else
                base_ni = ctx->ntfs_ino;

        /* Remove attribute itself. */
        if (ntfs_attr_record_resize(ctx->mrec, ctx->attr, 0)) {
                ntfs_debug("Couldn't remove attribute record. Bug or damaged MFT record.\n");
                return -EIO;
        }
        mark_mft_record_dirty(ni);

        /*
         * Remove record from $ATTRIBUTE_LIST if present and we don't want
         * delete $ATTRIBUTE_LIST itself.
         */
        if (NInoAttrList(base_ni) && type != AT_ATTRIBUTE_LIST) {
                err = ntfs_attrlist_entry_rm(ctx);
                if (err) {
                        ntfs_debug("Couldn't delete record from $ATTRIBUTE_LIST.\n");
                        return err;
                }
        }

        /* Post $ATTRIBUTE_LIST delete setup. */
        if (type == AT_ATTRIBUTE_LIST) {
                if (NInoAttrList(base_ni) && base_ni->attr_list)
                        kvfree(base_ni->attr_list);
                base_ni->attr_list = NULL;
                NInoClearAttrList(base_ni);
        }

        /* Free MFT record, if it doesn't contain attributes. */
        if (le32_to_cpu(ctx->mrec->bytes_in_use) -
                        le16_to_cpu(ctx->mrec->attrs_offset) == 8) {
                if (ntfs_mft_record_free(ni->vol, ni)) {
                        ntfs_debug("Couldn't free MFT record.\n");
                        return -EIO;
                }
                /* Remove done if we freed base inode. */
                if (ni == base_ni)
                        return 0;
                ntfs_inode_close(ni);
                ctx->ntfs_ino = ni = NULL;
        }

        if (type == AT_ATTRIBUTE_LIST || !NInoAttrList(base_ni))
                return 0;

        /* Remove attribute list if we don't need it any more. */
        if (!ntfs_attrlist_need(base_ni)) {
                struct ntfs_attr na;
                struct inode *attr_vi;

                ntfs_attr_reinit_search_ctx(ctx);
                if (ntfs_attr_lookup(AT_ATTRIBUTE_LIST, NULL, 0, CASE_SENSITIVE,
                                        0, NULL, 0, ctx)) {
                        ntfs_debug("Couldn't find attribute list. Succeed anyway.\n");
                        return 0;
                }
                /* Deallocate clusters. */
                if (ctx->attr->non_resident) {
                        struct runlist_element *al_rl;
                        size_t new_rl_count;

                        al_rl = ntfs_mapping_pairs_decompress(base_ni->vol,
                                        ctx->attr, NULL, &new_rl_count);
                        if (IS_ERR(al_rl)) {
                                ntfs_debug("Couldn't decompress attribute list runlist. Succeed anyway.\n");
                                return 0;
                        }
                        if (ntfs_cluster_free_from_rl(base_ni->vol, al_rl))
                                ntfs_debug("Leaking clusters! Run chkdsk. Couldn't free clusters from attribute list runlist.\n");
                        kvfree(al_rl);
                }
                /* Remove attribute record itself. */
                if (ntfs_attr_record_rm(ctx)) {
                        ntfs_debug("Couldn't remove attribute list. Succeed anyway.\n");
                        return 0;
                }

                na.mft_no = VFS_I(base_ni)->i_ino;
                na.type = AT_ATTRIBUTE_LIST;
                na.name = NULL;
                na.name_len = 0;

                attr_vi = ilookup5(VFS_I(base_ni)->i_sb, VFS_I(base_ni)->i_ino,
                                   ntfs_test_inode, &na);
                if (attr_vi) {
                        clear_nlink(attr_vi);
                        iput(attr_vi);
                }

        }
        return 0;
}

/*
 * ntfs_attr_add - add attribute to inode
 * @ni:         opened ntfs inode to which add attribute
 * @type:       type of the new attribute
 * @name:       name in unicode of the new attribute
 * @name_len:   name length in unicode characters of the new attribute
 * @val:        value of new attribute
 * @size:       size of the new attribute / length of @val (if specified)
 *
 * @val should always be specified for always resident attributes (eg. FILE_NAME
 * attribute), for attributes that can become non-resident @val can be NULL
 * (eg. DATA attribute). @size can be specified even if @val is NULL, in this
 * case data size will be equal to @size and initialized size will be equal
 * to 0.
 *
 * If inode haven't got enough space to add attribute, add attribute to one of
 * it extents, if no extents present or no one of them have enough space, than
 * allocate new extent and add attribute to it.
 *
 * If on one of this steps attribute list is needed but not present, than it is
 * added transparently to caller. So, this function should not be called with
 * @type == AT_ATTRIBUTE_LIST, if you really need to add attribute list call
 * ntfs_inode_add_attrlist instead.
 *
 * On success return 0. On error return -1 with errno set to the error code.
 */
int ntfs_attr_add(struct ntfs_inode *ni, __le32 type,
                __le16 *name, u8 name_len, u8 *val, s64 size)
{
        struct super_block *sb;
        u32 attr_rec_size;
        int err, i, offset;
        bool is_resident;
        bool can_be_non_resident = false;
        struct ntfs_inode *attr_ni;
        struct inode *attr_vi;
        struct mft_record *ni_mrec;

        if (!ni || size < 0 || type == AT_ATTRIBUTE_LIST)
                return -EINVAL;

        ntfs_debug("Entering for inode 0x%llx, attr %x, size %lld.\n",
                        (long long) ni->mft_no, type, size);

        if (ni->nr_extents == -1)
                ni = ni->ext.base_ntfs_ino;

        /* Check the attribute type and the size. */
        err = ntfs_attr_size_bounds_check(ni->vol, type, size);
        if (err) {
                if (err == -ENOENT)
                        err = -EIO;
                return err;
        }

        sb = ni->vol->sb;
        /* Sanity checks for always resident attributes. */
        err = ntfs_attr_can_be_non_resident(ni->vol, type);
        if (err) {
                if (err != -EPERM) {
                        ntfs_error(sb, "ntfs_attr_can_be_non_resident failed");
                        goto err_out;
                }
                /* @val is mandatory. */
                if (!val) {
                        ntfs_error(sb,
                                "val is mandatory for always resident attributes");
                        return -EINVAL;
                }
                if (size > ni->vol->mft_record_size) {
                        ntfs_error(sb, "Attribute is too big");
                        return -ERANGE;
                }
        } else
                can_be_non_resident = true;

        /*
         * Determine resident or not will be new attribute. We add 8 to size in
         * non resident case for mapping pairs.
         */
        err = ntfs_attr_can_be_resident(ni->vol, type);
        if (!err) {
                is_resident = true;
        } else {
                if (err != -EPERM) {
                        ntfs_error(sb, "ntfs_attr_can_be_resident failed");
                        goto err_out;
                }
                is_resident = false;
        }

        /* Calculate attribute record size. */
        if (is_resident)
                attr_rec_size = offsetof(struct attr_record, data.resident.reserved) +
                        1 +
                        ((name_len * sizeof(__le16) + 7) & ~7) +
                        ((size + 7) & ~7);
        else
                attr_rec_size = offsetof(struct attr_record, data.non_resident.compressed_size) +
                        ((name_len * sizeof(__le16) + 7) & ~7) + 8;

        /*
         * If we have enough free space for the new attribute in the base MFT
         * record, then add attribute to it.
         */
retry:
        ni_mrec = map_mft_record(ni);
        if (IS_ERR(ni_mrec)) {
                err = -EIO;
                goto err_out;
        }

        if (le32_to_cpu(ni_mrec->bytes_allocated) -
                        le32_to_cpu(ni_mrec->bytes_in_use) >= attr_rec_size) {
                attr_ni = ni;
                unmap_mft_record(ni);
                goto add_attr_record;
        }
        unmap_mft_record(ni);

        /* Try to add to extent inodes. */
        err = ntfs_inode_attach_all_extents(ni);
        if (err) {
                ntfs_error(sb, "Failed to attach all extents to inode");
                goto err_out;
        }

        for (i = 0; i < ni->nr_extents; i++) {
                attr_ni = ni->ext.extent_ntfs_inos[i];
                ni_mrec = map_mft_record(attr_ni);
                if (IS_ERR(ni_mrec)) {
                        err = -EIO;
                        goto err_out;
                }

                if (le32_to_cpu(ni_mrec->bytes_allocated) -
                                le32_to_cpu(ni_mrec->bytes_in_use) >=
                                attr_rec_size) {
                        unmap_mft_record(attr_ni);
                        goto add_attr_record;
                }
                unmap_mft_record(attr_ni);
        }

        /* There is no extent that contain enough space for new attribute. */
        if (!NInoAttrList(ni)) {
                /* Add attribute list not present, add it and retry. */
                err = ntfs_inode_add_attrlist(ni);
                if (err) {
                        ntfs_error(sb, "Failed to add attribute list");
                        goto err_out;
                }
                goto retry;
        }

        attr_ni = NULL;
        /* Allocate new extent. */
        err = ntfs_mft_record_alloc(ni->vol, 0, &attr_ni, ni, NULL);
        if (err) {
                ntfs_error(sb, "Failed to allocate extent record");
                goto err_out;
        }
        unmap_mft_record(attr_ni);

add_attr_record:
        if (is_resident) {
                /* Add resident attribute. */
                offset = ntfs_resident_attr_record_add(attr_ni, type, name,
                                name_len, val, size, 0);
                if (offset < 0) {
                        if (offset == -ENOSPC && can_be_non_resident)
                                goto add_non_resident;
                        err = offset;
                        ntfs_error(sb, "Failed to add resident attribute");
                        goto free_err_out;
                }
                return 0;
        }

add_non_resident:
        /* Add non resident attribute. */
        offset = ntfs_non_resident_attr_record_add(attr_ni, type, name,
                        name_len, 0, 8, 0);
        if (offset < 0) {
                err = offset;
                ntfs_error(sb, "Failed to add non resident attribute");
                goto free_err_out;
        }

        /* If @size == 0, we are done. */
        if (!size)
                return 0;

        /* Open new attribute and resize it. */
        attr_vi = ntfs_attr_iget(VFS_I(ni), type, name, name_len);
        if (IS_ERR(attr_vi)) {
                err = PTR_ERR(attr_vi);
                ntfs_error(sb, "Failed to open just added attribute");
                goto rm_attr_err_out;
        }
        attr_ni = NTFS_I(attr_vi);

        /* Resize and set attribute value. */
        if (ntfs_attr_truncate(attr_ni, size) ||
                (val && (ntfs_inode_attr_pwrite(attr_vi, 0, size, val, false) != size))) {
                err = -EIO;
                ntfs_error(sb, "Failed to initialize just added attribute");
                if (ntfs_attr_rm(attr_ni))
                        ntfs_error(sb, "Failed to remove just added attribute");
                iput(attr_vi);
                goto err_out;
        }
        iput(attr_vi);
        return 0;

rm_attr_err_out:
        /* Remove just added attribute. */
        ni_mrec = map_mft_record(attr_ni);
        if (!IS_ERR(ni_mrec)) {
                if (ntfs_attr_record_resize(ni_mrec,
                                        (struct attr_record *)((u8 *)ni_mrec + offset), 0))
                        ntfs_error(sb, "Failed to remove just added attribute #2");
                unmap_mft_record(attr_ni);
        } else
                pr_err("EIO when try to remove new added attr\n");

free_err_out:
        /* Free MFT record, if it doesn't contain attributes. */
        ni_mrec = map_mft_record(attr_ni);
        if (!IS_ERR(ni_mrec)) {
                int attr_size;

                attr_size = le32_to_cpu(ni_mrec->bytes_in_use) -
                        le16_to_cpu(ni_mrec->attrs_offset);
                unmap_mft_record(attr_ni);
                if (attr_size == 8) {
                        if (ntfs_mft_record_free(attr_ni->vol, attr_ni))
                                ntfs_error(sb, "Failed to free MFT record");
                        if (attr_ni->nr_extents < 0)
                                ntfs_inode_close(attr_ni);
                }
        } else
                pr_err("EIO when testing mft record is free-able\n");

err_out:
        return err;
}

/*
 * __ntfs_attr_init - primary initialization of an ntfs attribute structure
 * @ni:         ntfs attribute inode to initialize
 * @ni:         ntfs inode with which to initialize the ntfs attribute
 * @type:       attribute type
 * @name:       attribute name in little endian Unicode or NULL
 * @name_len:   length of attribute @name in Unicode characters (if @name given)
 *
 * Initialize the ntfs attribute @na with @ni, @type, @name, and @name_len.
 */
static void __ntfs_attr_init(struct ntfs_inode *ni,
                const __le32 type, __le16 *name, const u32 name_len)
{
        ni->runlist.rl = NULL;
        ni->type = type;
        ni->name = name;
        if (name)
                ni->name_len = name_len;
        else
                ni->name_len = 0;
}

/*
 * ntfs_attr_init - initialize an ntfs_attr with data sizes and status
 * @ni: ntfs inode to initialize
 * @non_resident: true if attribute is non-resident
 * @compressed: true if attribute is compressed
 * @encrypted: true if attribute is encrypted
 * @sparse: true if attribute is sparse
 * @allocated_size: allocated size of the attribute
 * @data_size: actual data size of the attribute
 * @initialized_size: initialized size of the attribute
 * @compressed_size: compressed size (if compressed or sparse)
 * @compression_unit: compression unit size (log2 of clusters)
 *
 * Final initialization for an ntfs attribute.
 */
static void ntfs_attr_init(struct ntfs_inode *ni, const bool non_resident,
                const bool compressed, const bool encrypted, const bool sparse,
                const s64 allocated_size, const s64 data_size,
                const s64 initialized_size, const s64 compressed_size,
                const u8 compression_unit)
{
        if (non_resident)
                NInoSetNonResident(ni);
        if (compressed) {
                NInoSetCompressed(ni);
                ni->flags |= FILE_ATTR_COMPRESSED;
        }
        if (encrypted) {
                NInoSetEncrypted(ni);
                ni->flags |= FILE_ATTR_ENCRYPTED;
        }
        if (sparse) {
                NInoSetSparse(ni);
                ni->flags |= FILE_ATTR_SPARSE_FILE;
        }
        ni->allocated_size = allocated_size;
        ni->data_size = data_size;
        ni->initialized_size = initialized_size;
        if (compressed || sparse) {
                struct ntfs_volume *vol = ni->vol;

                ni->itype.compressed.size = compressed_size;
                ni->itype.compressed.block_clusters = 1 << compression_unit;
                ni->itype.compressed.block_size = 1 << (compression_unit +
                                vol->cluster_size_bits);
                ni->itype.compressed.block_size_bits = ffs(
                                ni->itype.compressed.block_size) - 1;
        }
}

/*
 * ntfs_attr_open - open an ntfs attribute for access
 * @ni:         open ntfs inode in which the ntfs attribute resides
 * @type:       attribute type
 * @name:       attribute name in little endian Unicode or AT_UNNAMED or NULL
 * @name_len:   length of attribute @name in Unicode characters (if @name given)
 */
int ntfs_attr_open(struct ntfs_inode *ni, const __le32 type,
                __le16 *name, u32 name_len)
{
        struct ntfs_attr_search_ctx *ctx;
        __le16 *newname = NULL;
        struct attr_record *a;
        bool cs;
        struct ntfs_inode *base_ni;
        int err;

        if (!ni || !ni->vol)
                return -EINVAL;

        ntfs_debug("Entering for inode %lld, attr 0x%x.\n",
                        ni->mft_no, type);

        if (NInoAttr(ni))
                base_ni = ni->ext.base_ntfs_ino;
        else
                base_ni = ni;

        if (name && name != AT_UNNAMED && name != I30) {
                name = ntfs_ucsndup(name, name_len);
                if (!name) {
                        err = -ENOMEM;
                        goto err_out;
                }
                newname = name;
        }

        ctx = ntfs_attr_get_search_ctx(base_ni, NULL);
        if (!ctx) {
                err = -ENOMEM;
                pr_err("%s: Failed to get search context\n", __func__);
                goto err_out;
        }

        err = ntfs_attr_lookup(type, name, name_len, 0, 0, NULL, 0, ctx);
        if (err)
                goto put_err_out;

        a = ctx->attr;

        if (!name) {
                if (a->name_length) {
                        name = ntfs_ucsndup((__le16 *)((u8 *)a + le16_to_cpu(a->name_offset)),
                                            a->name_length);
                        if (!name)
                                goto put_err_out;
                        newname = name;
                        name_len = a->name_length;
                } else {
                        name = AT_UNNAMED;
                        name_len = 0;
                }
        }

        __ntfs_attr_init(ni, type, name, name_len);

        /*
         * Wipe the flags in case they are not zero for an attribute list
         * attribute.  Windows does not complain about invalid flags and chkdsk
         * does not detect or fix them so we need to cope with it, too.
         */
        if (type == AT_ATTRIBUTE_LIST)
                a->flags = 0;

        if ((type == AT_DATA) &&
            (a->non_resident ? !a->data.non_resident.initialized_size :
             !a->data.resident.value_length)) {
                /*
                 * Define/redefine the compression state if stream is
                 * empty, based on the compression mark on parent
                 * directory (for unnamed data streams) or on current
                 * inode (for named data streams). The compression mark
                 * may change any time, the compression state can only
                 * change when stream is wiped out.
                 *
                 * Also prevent compression on NTFS version < 3.0
                 * or cluster size > 4K or compression is disabled
                 */
                a->flags &= ~ATTR_COMPRESSION_MASK;
                if (NInoCompressed(ni)
                                && (ni->vol->major_ver >= 3)
                                && NVolCompression(ni->vol)
                                && (ni->vol->cluster_size <= MAX_COMPRESSION_CLUSTER_SIZE))
                        a->flags |= ATTR_IS_COMPRESSED;
        }

        cs = a->flags & (ATTR_IS_COMPRESSED | ATTR_IS_SPARSE);

        if (ni->type == AT_DATA && ni->name == AT_UNNAMED &&
            ((!(a->flags & ATTR_IS_COMPRESSED) != !NInoCompressed(ni)) ||
             (!(a->flags & ATTR_IS_SPARSE)     != !NInoSparse(ni)) ||
             (!(a->flags & ATTR_IS_ENCRYPTED)  != !NInoEncrypted(ni)))) {
                err = -EIO;
                pr_err("Inode %lld has corrupt attribute flags (0x%x <> 0x%x)\n",
                                (unsigned long long)ni->mft_no,
                                a->flags, ni->flags);
                goto put_err_out;
        }

        if (a->non_resident) {
                if (((a->flags & ATTR_COMPRESSION_MASK) || a->data.non_resident.compression_unit) &&
                                (ni->vol->major_ver < 3)) {
                        err = -EIO;
                        pr_err("Compressed inode %lld not allowed  on NTFS %d.%d\n",
                                        (unsigned long long)ni->mft_no,
                                        ni->vol->major_ver,
                                        ni->vol->major_ver);
                        goto put_err_out;
                }

                if ((a->flags & ATTR_IS_COMPRESSED) && !a->data.non_resident.compression_unit) {
                        err = -EIO;
                        pr_err("Compressed inode %lld attr 0x%x has no compression unit\n",
                                        (unsigned long long)ni->mft_no, type);
                        goto put_err_out;
                }
                if ((a->flags & ATTR_COMPRESSION_MASK) &&
                    (a->data.non_resident.compression_unit != STANDARD_COMPRESSION_UNIT)) {
                        err = -EIO;
                        pr_err("Compressed inode %lld attr 0x%lx has an unsupported compression unit %d\n",
                                        (unsigned long long)ni->mft_no,
                                        (long)le32_to_cpu(type),
                                        (int)a->data.non_resident.compression_unit);
                        goto put_err_out;
                }
                ntfs_attr_init(ni, true, a->flags & ATTR_IS_COMPRESSED,
                                a->flags & ATTR_IS_ENCRYPTED,
                                a->flags & ATTR_IS_SPARSE,
                                le64_to_cpu(a->data.non_resident.allocated_size),
                                le64_to_cpu(a->data.non_resident.data_size),
                                le64_to_cpu(a->data.non_resident.initialized_size),
                                cs ? le64_to_cpu(a->data.non_resident.compressed_size) : 0,
                                cs ? a->data.non_resident.compression_unit : 0);
        } else {
                s64 l = le32_to_cpu(a->data.resident.value_length);

                ntfs_attr_init(ni, false, a->flags & ATTR_IS_COMPRESSED,
                                a->flags & ATTR_IS_ENCRYPTED,
                                a->flags & ATTR_IS_SPARSE, (l + 7) & ~7, l, l,
                                cs ? (l + 7) & ~7 : 0, 0);
        }
        ntfs_attr_put_search_ctx(ctx);
out:
        ntfs_debug("\n");
        return err;

put_err_out:
        ntfs_attr_put_search_ctx(ctx);
err_out:
        kfree(newname);
        goto out;
}

/*
 * ntfs_attr_close - free an ntfs attribute structure
 * @ni:         ntfs inode to free
 *
 * Release all memory associated with the ntfs attribute @na and then release
 * @na itself.
 */
void ntfs_attr_close(struct ntfs_inode *ni)
{
        if (NInoNonResident(ni) && ni->runlist.rl)
                kvfree(ni->runlist.rl);
        /* Don't release if using an internal constant. */
        if (ni->name != AT_UNNAMED && ni->name != I30)
                kfree(ni->name);
}

/*
 * ntfs_attr_map_whole_runlist - map the whole runlist of an ntfs attribute
 * @ni:         ntfs inode for which to map the runlist
 *
 * Map the whole runlist of the ntfs attribute @na.  For an attribute made up
 * of only one attribute extent this is the same as calling
 * ntfs_map_runlist(ni, 0) but for an attribute with multiple extents this
 * will map the runlist fragments from each of the extents thus giving access
 * to the entirety of the disk allocation of an attribute.
 */
int ntfs_attr_map_whole_runlist(struct ntfs_inode *ni)
{
        s64 next_vcn, last_vcn, highest_vcn;
        struct ntfs_attr_search_ctx *ctx;
        struct ntfs_volume *vol = ni->vol;
        struct super_block *sb = vol->sb;
        struct attr_record *a;
        int err;
        struct ntfs_inode *base_ni;
        int not_mapped;
        size_t new_rl_count;

        ntfs_debug("Entering for inode 0x%llx, attr 0x%x.\n",
                        (unsigned long long)ni->mft_no, ni->type);

        if (NInoFullyMapped(ni) && ni->runlist.rl)
                return 0;

        if (NInoAttr(ni))
                base_ni = ni->ext.base_ntfs_ino;
        else
                base_ni = ni;

        ctx = ntfs_attr_get_search_ctx(base_ni, NULL);
        if (!ctx) {
                ntfs_error(sb, "%s: Failed to get search context", __func__);
                return -ENOMEM;
        }

        /* Map all attribute extents one by one. */
        next_vcn = last_vcn = highest_vcn = 0;
        a = NULL;
        while (1) {
                struct runlist_element *rl;

                not_mapped = 0;
                if (ntfs_rl_vcn_to_lcn(ni->runlist.rl, next_vcn) == LCN_RL_NOT_MAPPED)
                        not_mapped = 1;

                err = ntfs_attr_lookup(ni->type, ni->name, ni->name_len,
                                        CASE_SENSITIVE, next_vcn, NULL, 0, ctx);
                if (err)
                        break;

                a = ctx->attr;

                if (not_mapped) {
                        /* Decode the runlist. */
                        rl = ntfs_mapping_pairs_decompress(ni->vol, a, &ni->runlist,
                                                           &new_rl_count);
                        if (IS_ERR(rl)) {
                                err = PTR_ERR(rl);
                                goto err_out;
                        }
                        ni->runlist.rl = rl;
                        ni->runlist.count = new_rl_count;
                }

                /* Are we in the first extent? */
                if (!next_vcn) {
                        if (a->data.non_resident.lowest_vcn) {
                                err = -EIO;
                                ntfs_error(sb,
                                        "First extent of inode %llu attribute has non-zero lowest_vcn",
                                        (unsigned long long)ni->mft_no);
                                goto err_out;
                        }
                        /* Get the last vcn in the attribute. */
                        last_vcn = ntfs_bytes_to_cluster(vol,
                                        le64_to_cpu(a->data.non_resident.allocated_size));
                }

                /* Get the lowest vcn for the next extent. */
                highest_vcn = le64_to_cpu(a->data.non_resident.highest_vcn);
                next_vcn = highest_vcn + 1;

                /* Only one extent or error, which we catch below. */
                if (next_vcn <= 0) {
                        err = -ENOENT;
                        break;
                }

                /* Avoid endless loops due to corruption. */
                if (next_vcn < le64_to_cpu(a->data.non_resident.lowest_vcn)) {
                        err = -EIO;
                        ntfs_error(sb, "Inode %llu has corrupt attribute list",
                                        (unsigned long long)ni->mft_no);
                        goto err_out;
                }
        }
        if (!a) {
                ntfs_error(sb, "Couldn't find attribute for runlist mapping");
                goto err_out;
        }
        if (not_mapped && highest_vcn && highest_vcn != last_vcn - 1) {
                err = -EIO;
                ntfs_error(sb,
                        "Failed to load full runlist: inode: %llu highest_vcn: 0x%llx last_vcn: 0x%llx",
                        (unsigned long long)ni->mft_no,
                        (long long)highest_vcn, (long long)last_vcn);
                goto err_out;
        }
        ntfs_attr_put_search_ctx(ctx);
        if (err == -ENOENT) {
                NInoSetFullyMapped(ni);
                return 0;
        }

        return err;

err_out:
        ntfs_attr_put_search_ctx(ctx);
        return err;
}

/*
 * ntfs_attr_record_move_to - move attribute record to target inode
 * @ctx:        attribute search context describing the attribute record
 * @ni:         opened ntfs inode to which move attribute record
 */
int ntfs_attr_record_move_to(struct ntfs_attr_search_ctx *ctx, struct ntfs_inode *ni)
{
        struct ntfs_attr_search_ctx *nctx;
        struct attr_record *a;
        int err;
        struct mft_record *ni_mrec;
        struct super_block *sb;

        if (!ctx || !ctx->attr || !ctx->ntfs_ino || !ni) {
                ntfs_debug("Invalid arguments passed.\n");
                return -EINVAL;
        }

        sb = ni->vol->sb;
        ntfs_debug("Entering for ctx->attr->type 0x%x, ctx->ntfs_ino->mft_no 0x%llx, ni->mft_no 0x%llx.\n",
                        (unsigned int) le32_to_cpu(ctx->attr->type),
                        (long long) ctx->ntfs_ino->mft_no,
                        (long long) ni->mft_no);

        if (ctx->ntfs_ino == ni)
                return 0;

        if (!ctx->al_entry) {
                ntfs_debug("Inode should contain attribute list to use this function.\n");
                return -EINVAL;
        }

        /* Find place in MFT record where attribute will be moved. */
        a = ctx->attr;
        nctx = ntfs_attr_get_search_ctx(ni, NULL);
        if (!nctx) {
                ntfs_error(sb, "%s: Failed to get search context", __func__);
                return -ENOMEM;
        }

        /*
         * Use ntfs_attr_find instead of ntfs_attr_lookup to find place for
         * attribute in @ni->mrec, not any extent inode in case if @ni is base
         * file record.
         */
        err = ntfs_attr_find(a->type, (__le16 *)((u8 *)a + le16_to_cpu(a->name_offset)),
                                a->name_length, CASE_SENSITIVE, NULL,
                                0, nctx);
        if (!err) {
                ntfs_debug("Attribute of such type, with same name already present in this MFT record.\n");
                err = -EEXIST;
                goto put_err_out;
        }
        if (err != -ENOENT) {
                ntfs_debug("Attribute lookup failed.\n");
                goto put_err_out;
        }

        /* Make space and move attribute. */
        ni_mrec = map_mft_record(ni);
        if (IS_ERR(ni_mrec)) {
                err = -EIO;
                goto put_err_out;
        }

        err = ntfs_make_room_for_attr(ni_mrec, (u8 *) nctx->attr,
                                le32_to_cpu(a->length));
        if (err) {
                ntfs_debug("Couldn't make space for attribute.\n");
                unmap_mft_record(ni);
                goto put_err_out;
        }
        memcpy(nctx->attr, a, le32_to_cpu(a->length));
        nctx->attr->instance = nctx->mrec->next_attr_instance;
        nctx->mrec->next_attr_instance =
                cpu_to_le16((le16_to_cpu(nctx->mrec->next_attr_instance) + 1) & 0xffff);
        ntfs_attr_record_resize(ctx->mrec, a, 0);
        mark_mft_record_dirty(ctx->ntfs_ino);
        mark_mft_record_dirty(ni);

        /* Update attribute list. */
        ctx->al_entry->mft_reference =
                MK_LE_MREF(ni->mft_no, le16_to_cpu(ni_mrec->sequence_number));
        ctx->al_entry->instance = nctx->attr->instance;
        unmap_mft_record(ni);
put_err_out:
        ntfs_attr_put_search_ctx(nctx);
        return err;
}

/*
 * ntfs_attr_record_move_away - move away attribute record from it's mft record
 * @ctx:        attribute search context describing the attribute record
 * @extra:      minimum amount of free space in the new holder of record
 */
int ntfs_attr_record_move_away(struct ntfs_attr_search_ctx *ctx, int extra)
{
        struct ntfs_inode *base_ni, *ni = NULL;
        struct mft_record *m;
        int i, err;
        struct super_block *sb;

        if (!ctx || !ctx->attr || !ctx->ntfs_ino || extra < 0)
                return -EINVAL;

        ntfs_debug("Entering for attr 0x%x, inode %llu\n",
                        (unsigned int) le32_to_cpu(ctx->attr->type),
                        (unsigned long long)ctx->ntfs_ino->mft_no);

        if (ctx->ntfs_ino->nr_extents == -1)
                base_ni = ctx->base_ntfs_ino;
        else
                base_ni = ctx->ntfs_ino;

        sb = ctx->ntfs_ino->vol->sb;
        if (!NInoAttrList(base_ni)) {
                ntfs_error(sb, "Inode %llu has no attrlist",
                                (unsigned long long)base_ni->mft_no);
                return -EINVAL;
        }

        err = ntfs_inode_attach_all_extents(ctx->ntfs_ino);
        if (err) {
                ntfs_error(sb, "Couldn't attach extents, inode=%llu",
                        (unsigned long long)base_ni->mft_no);
                return err;
        }

        mutex_lock(&base_ni->extent_lock);
        /* Walk through all extents and try to move attribute to them. */
        for (i = 0; i < base_ni->nr_extents; i++) {
                ni = base_ni->ext.extent_ntfs_inos[i];

                if (ctx->ntfs_ino->mft_no == ni->mft_no)
                        continue;
                m = map_mft_record(ni);
                if (IS_ERR(m)) {
                        ntfs_error(sb, "Can not map mft record for mft_no %lld",
                                        (unsigned long long)ni->mft_no);
                        mutex_unlock(&base_ni->extent_lock);
                        return -EIO;
                }
                if (le32_to_cpu(m->bytes_allocated) -
                    le32_to_cpu(m->bytes_in_use) < le32_to_cpu(ctx->attr->length) + extra) {
                        unmap_mft_record(ni);
                        continue;
                }
                unmap_mft_record(ni);

                /*
                 * ntfs_attr_record_move_to can fail if extent with other lowest
                 * s64 already present in inode we trying move record to. So,
                 * do not return error.
                 */
                if (!ntfs_attr_record_move_to(ctx, ni)) {
                        mutex_unlock(&base_ni->extent_lock);
                        return 0;
                }
        }
        mutex_unlock(&base_ni->extent_lock);

        /*
         * Failed to move attribute to one of the current extents, so allocate
         * new extent and move attribute to it.
         */
        ni = NULL;
        err = ntfs_mft_record_alloc(base_ni->vol, 0, &ni, base_ni, NULL);
        if (err) {
                ntfs_error(sb, "Couldn't allocate MFT record, err : %d", err);
                return err;
        }
        unmap_mft_record(ni);

        err = ntfs_attr_record_move_to(ctx, ni);
        if (err)
                ntfs_error(sb, "Couldn't move attribute to MFT record");

        return err;
}

/*
 * If we are in the first extent, then set/clean sparse bit,
 * update allocated and compressed size.
 */
static int ntfs_attr_update_meta(struct attr_record *a, struct ntfs_inode *ni,
                struct mft_record *m, struct ntfs_attr_search_ctx *ctx)
{
        int sparse, err = 0;
        struct ntfs_inode *base_ni;
        struct super_block *sb = ni->vol->sb;

        ntfs_debug("Entering for inode 0x%llx, attr 0x%x\n",
                        (unsigned long long)ni->mft_no, ni->type);

        if (NInoAttr(ni))
                base_ni = ni->ext.base_ntfs_ino;
        else
                base_ni = ni;

        if (a->data.non_resident.lowest_vcn)
                goto out;

        a->data.non_resident.allocated_size = cpu_to_le64(ni->allocated_size);

        sparse = ntfs_rl_sparse(ni->runlist.rl);
        if (sparse < 0) {
                err = -EIO;
                goto out;
        }

        /* Attribute become sparse. */
        if (sparse && !(a->flags & (ATTR_IS_SPARSE | ATTR_IS_COMPRESSED))) {
                /*
                 * Move attribute to another mft record, if attribute is too
                 * small to add compressed_size field to it and we have no
                 * free space in the current mft record.
                 */
                if ((le32_to_cpu(a->length) -
                     le16_to_cpu(a->data.non_resident.mapping_pairs_offset) == 8) &&
                    !(le32_to_cpu(m->bytes_allocated) - le32_to_cpu(m->bytes_in_use))) {

                        if (!NInoAttrList(base_ni)) {
                                err = ntfs_inode_add_attrlist(base_ni);
                                if (err)
                                        goto out;
                                err = -EAGAIN;
                                goto out;
                        }
                        err = ntfs_attr_record_move_away(ctx, 8);
                        if (err) {
                                ntfs_error(sb, "Failed to move attribute");
                                goto out;
                        }

                        err = ntfs_attrlist_update(base_ni);
                        if (err)
                                goto out;
                        err = -EAGAIN;
                        goto out;
                }
                if (!(le32_to_cpu(a->length) -
                    le16_to_cpu(a->data.non_resident.mapping_pairs_offset))) {
                        err = -EIO;
                        ntfs_error(sb, "Mapping pairs space is 0");
                        goto out;
                }

                NInoSetSparse(ni);
                ni->flags |= FILE_ATTR_SPARSE_FILE;
                a->flags |= ATTR_IS_SPARSE;
                a->data.non_resident.compression_unit = 0;

                memmove((u8 *)a + le16_to_cpu(a->name_offset) + 8,
                                (u8 *)a + le16_to_cpu(a->name_offset),
                                a->name_length * sizeof(__le16));

                a->name_offset = cpu_to_le16(le16_to_cpu(a->name_offset) + 8);

                a->data.non_resident.mapping_pairs_offset =
                        cpu_to_le16(le16_to_cpu(a->data.non_resident.mapping_pairs_offset) + 8);
        }

        /* Attribute no longer sparse. */
        if (!sparse && (a->flags & ATTR_IS_SPARSE) &&
            !(a->flags & ATTR_IS_COMPRESSED)) {
                NInoClearSparse(ni);
                ni->flags &= ~FILE_ATTR_SPARSE_FILE;
                a->flags &= ~ATTR_IS_SPARSE;
                a->data.non_resident.compression_unit = 0;

                memmove((u8 *)a + le16_to_cpu(a->name_offset) - 8,
                                (u8 *)a + le16_to_cpu(a->name_offset),
                                a->name_length * sizeof(__le16));

                if (le16_to_cpu(a->name_offset) >= 8)
                        a->name_offset = cpu_to_le16(le16_to_cpu(a->name_offset) - 8);

                a->data.non_resident.mapping_pairs_offset =
                        cpu_to_le16(le16_to_cpu(a->data.non_resident.mapping_pairs_offset) - 8);
        }

        /* Update compressed size if required. */
        if (NInoFullyMapped(ni) && (sparse || NInoCompressed(ni))) {
                s64 new_compr_size;

                new_compr_size = ntfs_rl_get_compressed_size(ni->vol, ni->runlist.rl);
                if (new_compr_size < 0) {
                        err = new_compr_size;
                        goto out;
                }

                ni->itype.compressed.size = new_compr_size;
                a->data.non_resident.compressed_size = cpu_to_le64(new_compr_size);
        }

        if (NInoSparse(ni) || NInoCompressed(ni))
                VFS_I(base_ni)->i_blocks = ni->itype.compressed.size >> 9;
        else
                VFS_I(base_ni)->i_blocks = ni->allocated_size >> 9;
        /*
         * Set FILE_NAME dirty flag, to update sparse bit and
         * allocated size in the index.
         */
        if (ni->type == AT_DATA && ni->name == AT_UNNAMED)
                NInoSetFileNameDirty(ni);
out:
        return err;
}

#define NTFS_VCN_DELETE_MARK -2
/*
 * ntfs_attr_update_mapping_pairs - update mapping pairs for ntfs attribute
 * @ni:         non-resident ntfs inode for which we need update
 * @from_vcn:   update runlist starting this VCN
 *
 * Build mapping pairs from @na->rl and write them to the disk. Also, this
 * function updates sparse bit, allocated and compressed size (allocates/frees
 * space for this field if required).
 *
 * @na->allocated_size should be set to correct value for the new runlist before
 * call to this function. Vice-versa @na->compressed_size will be calculated and
 * set to correct value during this function.
 */
int ntfs_attr_update_mapping_pairs(struct ntfs_inode *ni, s64 from_vcn)
{
        struct ntfs_attr_search_ctx *ctx;
        struct ntfs_inode *base_ni;
        struct mft_record *m;
        struct attr_record *a;
        s64 stop_vcn;
        int err = 0, mp_size, cur_max_mp_size, exp_max_mp_size;
        bool finished_build;
        bool first_updated = false;
        struct super_block *sb;
        struct runlist_element *start_rl;
        unsigned int de_cluster_count = 0;

retry:
        if (!ni || !ni->runlist.rl)
                return -EINVAL;

        ntfs_debug("Entering for inode %llu, attr 0x%x\n",
                        (unsigned long long)ni->mft_no, ni->type);

        sb = ni->vol->sb;
        if (!NInoNonResident(ni)) {
                ntfs_error(sb, "%s: resident attribute", __func__);
                return -EINVAL;
        }

        if (ni->nr_extents == -1)
                base_ni = ni->ext.base_ntfs_ino;
        else
                base_ni = ni;

        ctx = ntfs_attr_get_search_ctx(base_ni, NULL);
        if (!ctx) {
                ntfs_error(sb, "%s: Failed to get search context", __func__);
                return -ENOMEM;
        }

        /* Fill attribute records with new mapping pairs. */
        stop_vcn = 0;
        finished_build = false;
        start_rl = ni->runlist.rl;
        while (!(err = ntfs_attr_lookup(ni->type, ni->name, ni->name_len,
                                CASE_SENSITIVE, from_vcn, NULL, 0, ctx))) {
                unsigned int de_cnt = 0;

                a = ctx->attr;
                m = ctx->mrec;
                if (!a->data.non_resident.lowest_vcn)
                        first_updated = true;

                /*
                 * If runlist is updating not from the beginning, then set
                 * @stop_vcn properly, i.e. to the lowest vcn of record that
                 * contain @from_vcn. Also we do not need @from_vcn anymore,
                 * set it to 0 to make ntfs_attr_lookup enumerate attributes.
                 */
                if (from_vcn) {
                        s64 first_lcn;

                        stop_vcn = le64_to_cpu(a->data.non_resident.lowest_vcn);
                        from_vcn = 0;
                        /*
                         * Check whether the first run we need to update is
                         * the last run in runlist, if so, then deallocate
                         * all attrubute extents starting this one.
                         */
                        first_lcn = ntfs_rl_vcn_to_lcn(ni->runlist.rl, stop_vcn);
                        if (first_lcn == LCN_EINVAL) {
                                err = -EIO;
                                ntfs_error(sb, "Bad runlist");
                                goto put_err_out;
                        }
                        if (first_lcn == LCN_ENOENT ||
                            first_lcn == LCN_RL_NOT_MAPPED)
                                finished_build = true;
                }

                /*
                 * Check whether we finished mapping pairs build, if so mark
                 * extent as need to delete (by setting highest vcn to
                 * NTFS_VCN_DELETE_MARK (-2), we shall check it later and
                 * delete extent) and continue search.
                 */
                if (finished_build) {
                        ntfs_debug("Mark attr 0x%x for delete in inode 0x%llx.\n",
                                (unsigned int)le32_to_cpu(a->type), ctx->ntfs_ino->mft_no);
                        a->data.non_resident.highest_vcn = cpu_to_le64(NTFS_VCN_DELETE_MARK);
                        mark_mft_record_dirty(ctx->ntfs_ino);
                        continue;
                }

                err = ntfs_attr_update_meta(a, ni, m, ctx);
                if (err < 0) {
                        if (err == -EAGAIN) {
                                ntfs_attr_put_search_ctx(ctx);
                                goto retry;
                        }
                        goto put_err_out;
                }

                /*
                 * Determine maximum possible length of mapping pairs,
                 * if we shall *not* expand space for mapping pairs.
                 */
                cur_max_mp_size = le32_to_cpu(a->length) -
                        le16_to_cpu(a->data.non_resident.mapping_pairs_offset);
                /*
                 * Determine maximum possible length of mapping pairs in the
                 * current mft record, if we shall expand space for mapping
                 * pairs.
                 */
                exp_max_mp_size = le32_to_cpu(m->bytes_allocated) -
                        le32_to_cpu(m->bytes_in_use) + cur_max_mp_size;

                /* Get the size for the rest of mapping pairs array. */
                mp_size = ntfs_get_size_for_mapping_pairs(ni->vol, start_rl,
                                stop_vcn, -1, exp_max_mp_size);
                if (mp_size <= 0) {
                        err = mp_size;
                        ntfs_error(sb, "%s: get MP size failed", __func__);
                        goto put_err_out;
                }
                /* Test mapping pairs for fitting in the current mft record. */
                if (mp_size > exp_max_mp_size) {
                        /*
                         * Mapping pairs of $ATTRIBUTE_LIST attribute must fit
                         * in the base mft record. Try to move out other
                         * attributes and try again.
                         */
                        if (ni->type == AT_ATTRIBUTE_LIST) {
                                ntfs_attr_put_search_ctx(ctx);
                                if (ntfs_inode_free_space(base_ni, mp_size -
                                                        cur_max_mp_size)) {
                                        ntfs_debug("Attribute list is too big. Defragment the volume\n");
                                        return -ENOSPC;
                                }
                                if (ntfs_attrlist_update(base_ni))
                                        return -EIO;
                                goto retry;
                        }

                        /* Add attribute list if it isn't present, and retry. */
                        if (!NInoAttrList(base_ni)) {
                                ntfs_attr_put_search_ctx(ctx);
                                if (ntfs_inode_add_attrlist(base_ni)) {
                                        ntfs_error(sb, "Can not add attrlist");
                                        return -EIO;
                                }
                                goto retry;
                        }

                        /*
                         * Set mapping pairs size to maximum possible for this
                         * mft record. We shall write the rest of mapping pairs
                         * to another MFT records.
                         */
                        mp_size = exp_max_mp_size;
                }

                /* Change space for mapping pairs if we need it. */
                if (((mp_size + 7) & ~7) != cur_max_mp_size) {
                        if (ntfs_attr_record_resize(m, a,
                                        le16_to_cpu(a->data.non_resident.mapping_pairs_offset) +
                                                mp_size)) {
                                err = -EIO;
                                ntfs_error(sb, "Failed to resize attribute");
                                goto put_err_out;
                        }
                }

                /* Update lowest vcn. */
                a->data.non_resident.lowest_vcn = cpu_to_le64(stop_vcn);
                mark_mft_record_dirty(ctx->ntfs_ino);
                if ((ctx->ntfs_ino->nr_extents == -1 || NInoAttrList(ctx->ntfs_ino)) &&
                    ctx->attr->type != AT_ATTRIBUTE_LIST) {
                        ctx->al_entry->lowest_vcn = cpu_to_le64(stop_vcn);
                        err = ntfs_attrlist_update(base_ni);
                        if (err)
                                goto put_err_out;
                }

                /*
                 * Generate the new mapping pairs array directly into the
                 * correct destination, i.e. the attribute record itself.
                 */
                err = ntfs_mapping_pairs_build(ni->vol,
                                (u8 *)a + le16_to_cpu(a->data.non_resident.mapping_pairs_offset),
                                mp_size, start_rl, stop_vcn, -1, &stop_vcn, &start_rl, &de_cnt);
                if (!err)
                        finished_build = true;
                if (!finished_build && err != -ENOSPC) {
                        ntfs_error(sb, "Failed to build mapping pairs");
                        goto put_err_out;
                }
                a->data.non_resident.highest_vcn = cpu_to_le64(stop_vcn - 1);
                mark_mft_record_dirty(ctx->ntfs_ino);
                de_cluster_count += de_cnt;
        }

        /* Check whether error occurred. */
        if (err && err != -ENOENT) {
                ntfs_error(sb, "%s: Attribute lookup failed", __func__);
                goto put_err_out;
        }

        /*
         * If the base extent was skipped in the above process,
         * we still may have to update the sizes.
         */
        if (!first_updated) {
                ntfs_attr_reinit_search_ctx(ctx);
                err = ntfs_attr_lookup(ni->type, ni->name, ni->name_len,
                                CASE_SENSITIVE, 0, NULL, 0, ctx);
                if (!err) {
                        a = ctx->attr;
                        a->data.non_resident.allocated_size = cpu_to_le64(ni->allocated_size);
                        if (NInoCompressed(ni) || NInoSparse(ni))
                                a->data.non_resident.compressed_size =
                                        cpu_to_le64(ni->itype.compressed.size);
                        /* Updating sizes taints the extent holding the attr */
                        if (ni->type == AT_DATA && ni->name == AT_UNNAMED)
                                NInoSetFileNameDirty(ni);
                        mark_mft_record_dirty(ctx->ntfs_ino);
                } else {
                        ntfs_error(sb, "Failed to update sizes in base extent\n");
                        goto put_err_out;
                }
        }

        /* Deallocate not used attribute extents and return with success. */
        if (finished_build) {
                ntfs_attr_reinit_search_ctx(ctx);
                ntfs_debug("Deallocate marked extents.\n");
                while (!(err = ntfs_attr_lookup(ni->type, ni->name, ni->name_len,
                                CASE_SENSITIVE, 0, NULL, 0, ctx))) {
                        if (le64_to_cpu(ctx->attr->data.non_resident.highest_vcn) !=
                                        NTFS_VCN_DELETE_MARK)
                                continue;
                        /* Remove unused attribute record. */
                        err = ntfs_attr_record_rm(ctx);
                        if (err) {
                                ntfs_error(sb, "Could not remove unused attr");
                                goto put_err_out;
                        }
                        ntfs_attr_reinit_search_ctx(ctx);
                }
                if (err && err != -ENOENT) {
                        ntfs_error(sb, "%s: Attr lookup failed", __func__);
                        goto put_err_out;
                }
                ntfs_debug("Deallocate done.\n");
                ntfs_attr_put_search_ctx(ctx);
                goto out;
        }
        ntfs_attr_put_search_ctx(ctx);
        ctx = NULL;

        /* Allocate new MFT records for the rest of mapping pairs. */
        while (1) {
                struct ntfs_inode *ext_ni = NULL;
                unsigned int de_cnt = 0;

                /* Allocate new mft record. */
                err = ntfs_mft_record_alloc(ni->vol, 0, &ext_ni, base_ni, NULL);
                if (err) {
                        ntfs_error(sb, "Failed to allocate extent record");
                        goto put_err_out;
                }
                unmap_mft_record(ext_ni);

                m = map_mft_record(ext_ni);
                if (IS_ERR(m)) {
                        ntfs_error(sb, "Could not map new MFT record");
                        if (ntfs_mft_record_free(ni->vol, ext_ni))
                                ntfs_error(sb, "Could not free MFT record");
                        ntfs_inode_close(ext_ni);
                        err = -ENOMEM;
                        ext_ni = NULL;
                        goto put_err_out;
                }
                /*
                 * If mapping size exceed available space, set them to
                 * possible maximum.
                 */
                cur_max_mp_size = le32_to_cpu(m->bytes_allocated) -
                        le32_to_cpu(m->bytes_in_use) -
                        (sizeof(struct attr_record) +
                         ((NInoCompressed(ni) || NInoSparse(ni)) ?
                          sizeof(a->data.non_resident.compressed_size) : 0)) -
                        ((sizeof(__le16) * ni->name_len + 7) & ~7);

                /* Calculate size of rest mapping pairs. */
                mp_size = ntfs_get_size_for_mapping_pairs(ni->vol,
                                start_rl, stop_vcn, -1, cur_max_mp_size);
                if (mp_size <= 0) {
                        unmap_mft_record(ext_ni);
                        ntfs_inode_close(ext_ni);
                        err = mp_size;
                        ntfs_error(sb, "%s: get mp size failed", __func__);
                        goto put_err_out;
                }

                if (mp_size > cur_max_mp_size)
                        mp_size = cur_max_mp_size;
                /* Add attribute extent to new record. */
                err = ntfs_non_resident_attr_record_add(ext_ni, ni->type,
                                ni->name, ni->name_len, stop_vcn, mp_size, 0);
                if (err < 0) {
                        ntfs_error(sb, "Could not add attribute extent");
                        unmap_mft_record(ext_ni);
                        if (ntfs_mft_record_free(ni->vol, ext_ni))
                                ntfs_error(sb, "Could not free MFT record");
                        ntfs_inode_close(ext_ni);
                        goto put_err_out;
                }
                a = (struct attr_record *)((u8 *)m + err);

                err = ntfs_mapping_pairs_build(ni->vol, (u8 *)a +
                                le16_to_cpu(a->data.non_resident.mapping_pairs_offset),
                                mp_size, start_rl, stop_vcn, -1, &stop_vcn, &start_rl,
                                &de_cnt);
                if (err < 0 && err != -ENOSPC) {
                        ntfs_error(sb, "Failed to build MP");
                        unmap_mft_record(ext_ni);
                        if (ntfs_mft_record_free(ni->vol, ext_ni))
                                ntfs_error(sb, "Couldn't free MFT record");
                        goto put_err_out;
                }
                a->data.non_resident.highest_vcn = cpu_to_le64(stop_vcn - 1);
                mark_mft_record_dirty(ext_ni);
                unmap_mft_record(ext_ni);

                de_cluster_count += de_cnt;
                /* All mapping pairs has been written. */
                if (!err)
                        break;
        }
out:
        if (from_vcn == 0)
                ni->i_dealloc_clusters = de_cluster_count;
        return 0;

put_err_out:
        if (ctx)
                ntfs_attr_put_search_ctx(ctx);
        return err;
}

/*
 * ntfs_attr_make_resident - convert a non-resident to a resident attribute
 * @ni:         open ntfs attribute to make resident
 * @ctx:        ntfs search context describing the attribute
 *
 * Convert a non-resident ntfs attribute to a resident one.
 */
static int ntfs_attr_make_resident(struct ntfs_inode *ni, struct ntfs_attr_search_ctx *ctx)
{
        struct ntfs_volume *vol = ni->vol;
        struct super_block *sb = vol->sb;
        struct attr_record *a = ctx->attr;
        int name_ofs, val_ofs, err;
        s64 arec_size;

        ntfs_debug("Entering for inode 0x%llx, attr 0x%x.\n",
                        (unsigned long long)ni->mft_no, ni->type);

        /* Should be called for the first extent of the attribute. */
        if (le64_to_cpu(a->data.non_resident.lowest_vcn)) {
                ntfs_debug("Eeek!  Should be called for the first extent of the attribute.  Aborting...\n");
                return -EINVAL;
        }

        /* Some preliminary sanity checking. */
        if (!NInoNonResident(ni)) {
                ntfs_debug("Eeek!  Trying to make resident attribute resident. Aborting...\n");
                return -EINVAL;
        }

        /* Make sure this is not $MFT/$BITMAP or Windows will not boot! */
        if (ni->type == AT_BITMAP && ni->mft_no == FILE_MFT)
                return -EPERM;

        /* Check that the attribute is allowed to be resident. */
        err = ntfs_attr_can_be_resident(vol, ni->type);
        if (err)
                return err;

        if (NInoCompressed(ni) || NInoEncrypted(ni)) {
                ntfs_debug("Making compressed or encrypted files resident is not implemented yet.\n");
                return -EOPNOTSUPP;
        }

        /* Work out offsets into and size of the resident attribute. */
        name_ofs = 24; /* = sizeof(resident_struct attr_record); */
        val_ofs = (name_ofs + a->name_length * sizeof(__le16) + 7) & ~7;
        arec_size = (val_ofs + ni->data_size + 7) & ~7;

        /* Sanity check the size before we start modifying the attribute. */
        if (le32_to_cpu(ctx->mrec->bytes_in_use) - le32_to_cpu(a->length) +
            arec_size > le32_to_cpu(ctx->mrec->bytes_allocated)) {
                ntfs_debug("Not enough space to make attribute resident\n");
                return -ENOSPC;
        }

        /* Read and cache the whole runlist if not already done. */
        err = ntfs_attr_map_whole_runlist(ni);
        if (err)
                return err;

        /* Move the attribute name if it exists and update the offset. */
        if (a->name_length) {
                memmove((u8 *)a + name_ofs, (u8 *)a + le16_to_cpu(a->name_offset),
                                a->name_length * sizeof(__le16));
        }
        a->name_offset = cpu_to_le16(name_ofs);

        /* Resize the resident part of the attribute record. */
        if (ntfs_attr_record_resize(ctx->mrec, a, arec_size) < 0) {
                /*
                 * Bug, because ntfs_attr_record_resize should not fail (we
                 * already checked that attribute fits MFT record).
                 */
                ntfs_error(ctx->ntfs_ino->vol->sb, "BUG! Failed to resize attribute record. ");
                return -EIO;
        }

        /* Convert the attribute record to describe a resident attribute. */
        a->non_resident = 0;
        a->flags = 0;
        a->data.resident.value_length = cpu_to_le32(ni->data_size);
        a->data.resident.value_offset = cpu_to_le16(val_ofs);
        /*
         * File names cannot be non-resident so we would never see this here
         * but at least it serves as a reminder that there may be attributes
         * for which we do need to set this flag. (AIA)
         */
        if (a->type == AT_FILE_NAME)
                a->data.resident.flags = RESIDENT_ATTR_IS_INDEXED;
        else
                a->data.resident.flags = 0;
        a->data.resident.reserved = 0;

        /*
         * Deallocate clusters from the runlist.
         *
         * NOTE: We can use ntfs_cluster_free() because we have already mapped
         * the whole run list and thus it doesn't matter that the attribute
         * record is in a transiently corrupted state at this moment in time.
         */
        err = ntfs_cluster_free(ni, 0, -1, ctx);
        if (err) {
                ntfs_error(sb, "Eeek! Failed to release allocated clusters");
                ntfs_debug("Ignoring error and leaving behind wasted clusters.\n");
        }

        /* Throw away the now unused runlist. */
        kvfree(ni->runlist.rl);
        ni->runlist.rl = NULL;
        ni->runlist.count = 0;
        /* Update in-memory struct ntfs_attr. */
        NInoClearNonResident(ni);
        NInoClearCompressed(ni);
        ni->flags &= ~FILE_ATTR_COMPRESSED;
        NInoClearSparse(ni);
        ni->flags &= ~FILE_ATTR_SPARSE_FILE;
        NInoClearEncrypted(ni);
        ni->flags &= ~FILE_ATTR_ENCRYPTED;
        ni->initialized_size = ni->data_size;
        ni->allocated_size = ni->itype.compressed.size = (ni->data_size + 7) & ~7;
        ni->itype.compressed.block_size = 0;
        ni->itype.compressed.block_size_bits = ni->itype.compressed.block_clusters = 0;
        return 0;
}

/*
 * ntfs_non_resident_attr_shrink - shrink a non-resident, open ntfs attribute
 * @ni:         non-resident ntfs attribute to shrink
 * @newsize:    new size (in bytes) to which to shrink the attribute
 *
 * Reduce the size of a non-resident, open ntfs attribute @na to @newsize bytes.
 */
static int ntfs_non_resident_attr_shrink(struct ntfs_inode *ni, const s64 newsize)
{
        struct ntfs_volume *vol;
        struct ntfs_attr_search_ctx *ctx;
        s64 first_free_vcn;
        s64 nr_freed_clusters;
        int err;
        struct ntfs_inode *base_ni;

        ntfs_debug("Inode 0x%llx attr 0x%x new size %lld\n",
                (unsigned long long)ni->mft_no, ni->type, (long long)newsize);

        vol = ni->vol;

        if (NInoAttr(ni))
                base_ni = ni->ext.base_ntfs_ino;
        else
                base_ni = ni;

        /*
         * Check the attribute type and the corresponding minimum size
         * against @newsize and fail if @newsize is too small.
         */
        err = ntfs_attr_size_bounds_check(vol, ni->type, newsize);
        if (err) {
                if (err == -ERANGE)
                        ntfs_debug("Eeek! Size bounds check failed. Aborting...\n");
                else if (err == -ENOENT)
                        err = -EIO;
                return err;
        }

        /* The first cluster outside the new allocation. */
        if (NInoCompressed(ni))
                /*
                 * For compressed files we must keep full compressions blocks,
                 * but currently we do not decompress/recompress the last
                 * block to truncate the data, so we may leave more allocated
                 * clusters than really needed.
                 */
                first_free_vcn = ntfs_bytes_to_cluster(vol,
                                ((newsize - 1) | (ni->itype.compressed.block_size - 1)) + 1);
        else
                first_free_vcn =
                        ntfs_bytes_to_cluster(vol, newsize + vol->cluster_size - 1);

        if (first_free_vcn < 0)
                return -EINVAL;
        /*
         * Compare the new allocation with the old one and only deallocate
         * clusters if there is a change.
         */
        if (ntfs_bytes_to_cluster(vol, ni->allocated_size) != first_free_vcn) {
                struct ntfs_attr_search_ctx *ctx;

                err = ntfs_attr_map_whole_runlist(ni);
                if (err) {
                        ntfs_debug("Eeek! ntfs_attr_map_whole_runlist failed.\n");
                        return err;
                }

                ctx = ntfs_attr_get_search_ctx(ni, NULL);
                if (!ctx) {
                        ntfs_error(vol->sb, "%s: Failed to get search context", __func__);
                        return -ENOMEM;
                }

                /* Deallocate all clusters starting with the first free one. */
                nr_freed_clusters = ntfs_cluster_free(ni, first_free_vcn, -1, ctx);
                if (nr_freed_clusters < 0) {
                        ntfs_debug("Eeek! Freeing of clusters failed. Aborting...\n");
                        ntfs_attr_put_search_ctx(ctx);
                        return (int)nr_freed_clusters;
                }
                ntfs_attr_put_search_ctx(ctx);

                /* Truncate the runlist itself. */
                if (ntfs_rl_truncate_nolock(vol, &ni->runlist, first_free_vcn)) {
                        /*
                         * Failed to truncate the runlist, so just throw it
                         * away, it will be mapped afresh on next use.
                         */
                        kvfree(ni->runlist.rl);
                        ni->runlist.rl = NULL;
                        ntfs_error(vol->sb, "Eeek! Run list truncation failed.\n");
                        return -EIO;
                }

                /* Prepare to mapping pairs update. */
                ni->allocated_size = ntfs_cluster_to_bytes(vol, first_free_vcn);

                if (NInoSparse(ni) || NInoCompressed(ni)) {
                        if (nr_freed_clusters) {
                                ni->itype.compressed.size -=
                                        ntfs_cluster_to_bytes(vol, nr_freed_clusters);
                                VFS_I(base_ni)->i_blocks = ni->itype.compressed.size >> 9;
                        }
                } else
                        VFS_I(base_ni)->i_blocks = ni->allocated_size >> 9;

                /* Write mapping pairs for new runlist. */
                err = ntfs_attr_update_mapping_pairs(ni, 0 /*first_free_vcn*/);
                if (err) {
                        ntfs_debug("Eeek! Mapping pairs update failed. Leaving inconstant metadata. Run chkdsk.\n");
                        return err;
                }
        }

        /* Get the first attribute record. */
        ctx = ntfs_attr_get_search_ctx(base_ni, NULL);
        if (!ctx) {
                ntfs_error(vol->sb, "%s: Failed to get search context", __func__);
                return -ENOMEM;
        }

        err = ntfs_attr_lookup(ni->type, ni->name, ni->name_len, CASE_SENSITIVE,
                                0, NULL, 0, ctx);
        if (err) {
                if (err == -ENOENT)
                        err = -EIO;
                ntfs_debug("Eeek! Lookup of first attribute extent failed. Leaving inconstant metadata.\n");
                goto put_err_out;
        }

        /* Update data and initialized size. */
        ni->data_size = newsize;
        ctx->attr->data.non_resident.data_size = cpu_to_le64(newsize);
        if (newsize < ni->initialized_size) {
                ni->initialized_size = newsize;
                ctx->attr->data.non_resident.initialized_size = cpu_to_le64(newsize);
        }
        /* Update data size in the index. */
        if (ni->type == AT_DATA && ni->name == AT_UNNAMED)
                NInoSetFileNameDirty(ni);

        /* If the attribute now has zero size, make it resident. */
        if (!newsize && !NInoEncrypted(ni) && !NInoCompressed(ni)) {
                err = ntfs_attr_make_resident(ni, ctx);
                if (err) {
                        /* If couldn't make resident, just continue. */
                        if (err != -EPERM)
                                ntfs_error(ni->vol->sb,
                                        "Failed to make attribute resident. Leaving as is...\n");
                }
        }

        /* Set the inode dirty so it is written out later. */
        mark_mft_record_dirty(ctx->ntfs_ino);
        /* Done! */
        ntfs_attr_put_search_ctx(ctx);
        return 0;
put_err_out:
        ntfs_attr_put_search_ctx(ctx);
        return err;
}

/*
 * ntfs_non_resident_attr_expand - expand a non-resident, open ntfs attribute
 * @ni:                 non-resident ntfs attribute to expand
 * @prealloc_size:      preallocation size (in bytes) to which to expand the attribute
 * @newsize:            new size (in bytes) to which to expand the attribute
 * @holes:              how to create a hole if expanding
 * @need_lock:          whether mrec lock is needed or not
 *
 * Expand the size of a non-resident, open ntfs attribute @na to @newsize bytes,
 * by allocating new clusters.
 */
static int ntfs_non_resident_attr_expand(struct ntfs_inode *ni, const s64 newsize,
                const s64 prealloc_size, unsigned int holes, bool need_lock)
{
        s64 lcn_seek_from;
        s64 first_free_vcn;
        struct ntfs_volume *vol;
        struct ntfs_attr_search_ctx *ctx = NULL;
        struct runlist_element *rl, *rln;
        s64 org_alloc_size, org_compressed_size;
        int err, err2;
        struct ntfs_inode *base_ni;
        struct super_block *sb = ni->vol->sb;
        size_t new_rl_count;

        ntfs_debug("Inode 0x%llx, attr 0x%x, new size %lld old size %lld\n",
                        (unsigned long long)ni->mft_no, ni->type,
                        (long long)newsize, (long long)ni->data_size);

        vol = ni->vol;

        if (NInoAttr(ni))
                base_ni = ni->ext.base_ntfs_ino;
        else
                base_ni = ni;

        /*
         * Check the attribute type and the corresponding maximum size
         * against @newsize and fail if @newsize is too big.
         */
        err = ntfs_attr_size_bounds_check(vol, ni->type, newsize);
        if (err < 0) {
                ntfs_error(sb, "%s: bounds check failed", __func__);
                return err;
        }

        /* Save for future use. */
        org_alloc_size = ni->allocated_size;
        org_compressed_size = ni->itype.compressed.size;

        /* The first cluster outside the new allocation. */
        if (prealloc_size)
                first_free_vcn =
                        ntfs_bytes_to_cluster(vol, prealloc_size + vol->cluster_size - 1);
        else
                first_free_vcn =
                        ntfs_bytes_to_cluster(vol, newsize + vol->cluster_size - 1);
        if (first_free_vcn < 0)
                return -EFBIG;

        /*
         * Compare the new allocation with the old one and only allocate
         * clusters if there is a change.
         */
        if (ntfs_bytes_to_cluster(vol, ni->allocated_size) < first_free_vcn) {
                err = ntfs_attr_map_whole_runlist(ni);
                if (err) {
                        ntfs_error(sb, "ntfs_attr_map_whole_runlist failed");
                        return err;
                }

                /*
                 * If we extend $DATA attribute on NTFS 3+ volume, we can add
                 * sparse runs instead of real allocation of clusters.
                 */
                if ((ni->type == AT_DATA && (vol->major_ver >= 3 || !NInoSparseDisabled(ni))) &&
                    (holes != HOLES_NO)) {
                        if (NInoCompressed(ni)) {
                                int last = 0, i = 0;
                                s64 alloc_size;
                                u64 more_entries = round_up(first_free_vcn -
                                                 ntfs_bytes_to_cluster(vol, ni->allocated_size),
                                                 ni->itype.compressed.block_clusters);

                                do_div(more_entries, ni->itype.compressed.block_clusters);

                                while (ni->runlist.rl[last].length)
                                        last++;

                                rl = ntfs_rl_realloc(ni->runlist.rl, last + 1,
                                                last + more_entries + 1);
                                if (IS_ERR(rl)) {
                                        err = -ENOMEM;
                                        goto put_err_out;
                                }

                                alloc_size = ni->allocated_size;
                                while (i++ < more_entries) {
                                        rl[last].vcn = ntfs_bytes_to_cluster(vol,
                                                        round_up(alloc_size, vol->cluster_size));
                                        rl[last].length = ni->itype.compressed.block_clusters -
                                                (rl[last].vcn &
                                                 (ni->itype.compressed.block_clusters - 1));
                                        rl[last].lcn = LCN_HOLE;
                                        last++;
                                        alloc_size += ni->itype.compressed.block_size;
                                }

                                rl[last].vcn = first_free_vcn;
                                rl[last].lcn = LCN_ENOENT;
                                rl[last].length = 0;

                                ni->runlist.rl = rl;
                                ni->runlist.count += more_entries;
                        } else {
                                rl = kmalloc(sizeof(struct runlist_element) * 2, GFP_NOFS);
                                if (!rl) {
                                        err = -ENOMEM;
                                        goto put_err_out;
                                }

                                rl[0].vcn = ntfs_bytes_to_cluster(vol, ni->allocated_size);
                                rl[0].lcn = LCN_HOLE;
                                rl[0].length = first_free_vcn -
                                        ntfs_bytes_to_cluster(vol, ni->allocated_size);
                                rl[1].vcn = first_free_vcn;
                                rl[1].lcn = LCN_ENOENT;
                                rl[1].length = 0;
                        }
                } else {
                        /*
                         * Determine first after last LCN of attribute.
                         * We will start seek clusters from this LCN to avoid
                         * fragmentation.  If there are no valid LCNs in the
                         * attribute let the cluster allocator choose the
                         * starting LCN.
                         */
                        lcn_seek_from = -1;
                        if (ni->runlist.rl->length) {
                                /* Seek to the last run list element. */
                                for (rl = ni->runlist.rl; (rl + 1)->length; rl++)
                                        ;
                                /*
                                 * If the last LCN is a hole or similar seek
                                 * back to last valid LCN.
                                 */
                                while (rl->lcn < 0 && rl != ni->runlist.rl)
                                        rl--;
                                /*
                                 * Only set lcn_seek_from it the LCN is valid.
                                 */
                                if (rl->lcn >= 0)
                                        lcn_seek_from = rl->lcn + rl->length;
                        }

                        rl = ntfs_cluster_alloc(vol,
                                        ntfs_bytes_to_cluster(vol, ni->allocated_size),
                                        first_free_vcn -
                                        ntfs_bytes_to_cluster(vol, ni->allocated_size),
                                        lcn_seek_from, DATA_ZONE, false, false, false);
                        if (IS_ERR(rl)) {
                                ntfs_debug("Cluster allocation failed (%lld)",
                                                (long long)first_free_vcn -
                                                ntfs_bytes_to_cluster(vol, ni->allocated_size));
                                return PTR_ERR(rl);
                        }
                }

                if (!NInoCompressed(ni)) {
                        /* Append new clusters to attribute runlist. */
                        rln = ntfs_runlists_merge(&ni->runlist, rl, 0, &new_rl_count);
                        if (IS_ERR(rln)) {
                                /* Failed, free just allocated clusters. */
                                ntfs_error(sb, "Run list merge failed");
                                ntfs_cluster_free_from_rl(vol, rl);
                                kvfree(rl);
                                return -EIO;
                        }
                        ni->runlist.rl = rln;
                        ni->runlist.count = new_rl_count;
                }

                /* Prepare to mapping pairs update. */
                ni->allocated_size = ntfs_cluster_to_bytes(vol, first_free_vcn);
                err = ntfs_attr_update_mapping_pairs(ni, 0);
                if (err) {
                        ntfs_debug("Mapping pairs update failed");
                        goto rollback;
                }
        }

        ctx = ntfs_attr_get_search_ctx(base_ni, NULL);
        if (!ctx) {
                err = -ENOMEM;
                if (ni->allocated_size == org_alloc_size)
                        return err;
                goto rollback;
        }

        err = ntfs_attr_lookup(ni->type, ni->name, ni->name_len, CASE_SENSITIVE,
                               0, NULL, 0, ctx);
        if (err) {
                if (err == -ENOENT)
                        err = -EIO;
                if (ni->allocated_size != org_alloc_size)
                        goto rollback;
                goto put_err_out;
        }

        /* Update data size. */
        ni->data_size = newsize;
        ctx->attr->data.non_resident.data_size = cpu_to_le64(newsize);
        /* Update data size in the index. */
        if (ni->type == AT_DATA && ni->name == AT_UNNAMED)
                NInoSetFileNameDirty(ni);
        /* Set the inode dirty so it is written out later. */
        mark_mft_record_dirty(ctx->ntfs_ino);
        /* Done! */
        ntfs_attr_put_search_ctx(ctx);
        return 0;
rollback:
        /* Free allocated clusters. */
        err2 = ntfs_cluster_free(ni, ntfs_bytes_to_cluster(vol, org_alloc_size),
                                -1, ctx);
        if (err2)
                ntfs_debug("Leaking clusters");

        /* Now, truncate the runlist itself. */
        if (need_lock)
                down_write(&ni->runlist.lock);
        err2 = ntfs_rl_truncate_nolock(vol, &ni->runlist,
                        ntfs_bytes_to_cluster(vol, org_alloc_size));
        if (need_lock)
                up_write(&ni->runlist.lock);
        if (err2) {
                /*
                 * Failed to truncate the runlist, so just throw it away, it
                 * will be mapped afresh on next use.
                 */
                kvfree(ni->runlist.rl);
                ni->runlist.rl = NULL;
                ntfs_error(sb, "Couldn't truncate runlist. Rollback failed");
        } else {
                /* Prepare to mapping pairs update. */
                ni->allocated_size = org_alloc_size;
                /* Restore mapping pairs. */
                if (need_lock)
                        down_read(&ni->runlist.lock);
                if (ntfs_attr_update_mapping_pairs(ni, 0))
                        ntfs_error(sb, "Failed to restore old mapping pairs");
                if (need_lock)
                        up_read(&ni->runlist.lock);

                if (NInoSparse(ni) || NInoCompressed(ni)) {
                        ni->itype.compressed.size =  org_compressed_size;
                        VFS_I(base_ni)->i_blocks = ni->itype.compressed.size >> 9;
                } else
                        VFS_I(base_ni)->i_blocks = ni->allocated_size >> 9;
        }
        if (ctx)
                ntfs_attr_put_search_ctx(ctx);
        return err;
put_err_out:
        if (ctx)
                ntfs_attr_put_search_ctx(ctx);
        return err;
}

/*
 * ntfs_resident_attr_resize - resize a resident, open ntfs attribute
 * @attr_ni:            resident ntfs inode to resize
 * @newsize:            new size (in bytes) to which to resize the attribute
 * @prealloc_size:      preallocation size (in bytes) to which to resize the attribute
 * @holes:              flags indicating how to handle holes
 *
 * Change the size of a resident, open ntfs attribute @na to @newsize bytes.
 */
static int ntfs_resident_attr_resize(struct ntfs_inode *attr_ni, const s64 newsize,
                const s64 prealloc_size, unsigned int holes)
{
        struct ntfs_attr_search_ctx *ctx;
        struct ntfs_volume *vol = attr_ni->vol;
        struct super_block *sb = vol->sb;
        int err = -EIO;
        struct ntfs_inode *base_ni, *ext_ni = NULL;

attr_resize_again:
        ntfs_debug("Inode 0x%llx attr 0x%x new size %lld\n",
                        (unsigned long long)attr_ni->mft_no, attr_ni->type,
                        (long long)newsize);

        if (NInoAttr(attr_ni))
                base_ni = attr_ni->ext.base_ntfs_ino;
        else
                base_ni = attr_ni;

        /* Get the attribute record that needs modification. */
        ctx = ntfs_attr_get_search_ctx(base_ni, NULL);
        if (!ctx) {
                ntfs_error(sb, "%s: Failed to get search context", __func__);
                return -ENOMEM;
        }

        err = ntfs_attr_lookup(attr_ni->type, attr_ni->name, attr_ni->name_len,
                        0, 0, NULL, 0, ctx);
        if (err) {
                ntfs_error(sb, "ntfs_attr_lookup failed");
                goto put_err_out;
        }

        /*
         * Check the attribute type and the corresponding minimum and maximum
         * sizes against @newsize and fail if @newsize is out of bounds.
         */
        err = ntfs_attr_size_bounds_check(vol, attr_ni->type, newsize);
        if (err) {
                if (err == -ENOENT)
                        err = -EIO;
                ntfs_debug("%s: bounds check failed", __func__);
                goto put_err_out;
        }
        /*
         * If @newsize is bigger than the mft record we need to make the
         * attribute non-resident if the attribute type supports it. If it is
         * smaller we can go ahead and attempt the resize.
         */
        if (newsize < vol->mft_record_size) {
                /* Perform the resize of the attribute record. */
                err = ntfs_resident_attr_value_resize(ctx->mrec, ctx->attr,
                                        newsize);
                if (!err) {
                        /* Update attribute size everywhere. */
                        attr_ni->data_size = attr_ni->initialized_size = newsize;
                        attr_ni->allocated_size = (newsize + 7) & ~7;
                        if (NInoCompressed(attr_ni) || NInoSparse(attr_ni))
                                attr_ni->itype.compressed.size = attr_ni->allocated_size;
                        if (attr_ni->type == AT_DATA && attr_ni->name == AT_UNNAMED)
                                NInoSetFileNameDirty(attr_ni);
                        goto resize_done;
                }

                /* Prefer AT_INDEX_ALLOCATION instead of AT_ATTRIBUTE_LIST */
                if (err == -ENOSPC && ctx->attr->type == AT_INDEX_ROOT)
                        goto put_err_out;

        }
        /* There is not enough space in the mft record to perform the resize. */

        /* Make the attribute non-resident if possible. */
        err = ntfs_attr_make_non_resident(attr_ni,
                        le32_to_cpu(ctx->attr->data.resident.value_length));
        if (!err) {
                mark_mft_record_dirty(ctx->ntfs_ino);
                ntfs_attr_put_search_ctx(ctx);
                /* Resize non-resident attribute */
                return ntfs_non_resident_attr_expand(attr_ni, newsize, prealloc_size, holes, true);
        } else if (err != -ENOSPC && err != -EPERM) {
                ntfs_error(sb, "Failed to make attribute non-resident");
                goto put_err_out;
        }

        /* Try to make other attributes non-resident and retry each time. */
        ntfs_attr_reinit_search_ctx(ctx);
        while (!(err = ntfs_attr_lookup(AT_UNUSED, NULL, 0, 0, 0, NULL, 0, ctx))) {
                struct inode *tvi;
                struct attr_record *a;
                u32 value_len;

                a = ctx->attr;
                if (a->non_resident || a->type == AT_ATTRIBUTE_LIST)
                        continue;
                value_len = le32_to_cpu(a->data.resident.value_length);

                if (ntfs_attr_can_be_non_resident(vol, a->type))
                        continue;

                /*
                 * Check out whether convert is reasonable. Assume that mapping
                 * pairs will take 8 bytes.
                 */
                if (le32_to_cpu(a->length) <= (sizeof(struct attr_record) - sizeof(s64)) +
                                ((a->name_length * sizeof(__le16) + 7) & ~7) + 8)
                        continue;
                if (a->type == AT_DATA && !value_len)
                        continue;

                if (a->type == AT_DATA)
                        tvi = ntfs_iget(sb, base_ni->mft_no);
                else
                        tvi = ntfs_attr_iget(VFS_I(base_ni), a->type,
                                (__le16 *)((u8 *)a + le16_to_cpu(a->name_offset)),
                                a->name_length);
                if (IS_ERR(tvi)) {
                        ntfs_error(sb, "Couldn't open attribute");
                        continue;
                }

                if (ntfs_attr_make_non_resident(NTFS_I(tvi), value_len)) {
                        iput(tvi);
                        continue;
                }

                mark_mft_record_dirty(ctx->ntfs_ino);
                iput(tvi);
                ntfs_attr_put_search_ctx(ctx);
                goto attr_resize_again;
        }

        /* Check whether error occurred. */
        if (err != -ENOENT) {
                ntfs_error(sb, "%s: Attribute lookup failed 1", __func__);
                goto put_err_out;
        }

        /*
         * The standard information and attribute list attributes can't be
         * moved out from the base MFT record, so try to move out others.
         */
        if (attr_ni->type == AT_STANDARD_INFORMATION ||
            attr_ni->type == AT_ATTRIBUTE_LIST) {
                ntfs_attr_put_search_ctx(ctx);

                if (!NInoAttrList(base_ni)) {
                        err = ntfs_inode_add_attrlist(base_ni);
                        if (err)
                                return err;
                }

                err = ntfs_inode_free_space(base_ni, sizeof(struct attr_record));
                if (err) {
                        err = -ENOSPC;
                        ntfs_error(sb,
                                "Couldn't free space in the MFT record to make attribute list non resident");
                        return err;
                }
                err = ntfs_attrlist_update(base_ni);
                if (err)
                        return err;
                goto attr_resize_again;
        }

        /*
         * Move the attribute to a new mft record, creating an attribute list
         * attribute or modifying it if it is already present.
         */

        /* Point search context back to attribute which we need resize. */
        ntfs_attr_reinit_search_ctx(ctx);
        err = ntfs_attr_lookup(attr_ni->type, attr_ni->name, attr_ni->name_len,
                        CASE_SENSITIVE, 0, NULL, 0, ctx);
        if (err) {
                ntfs_error(sb, "%s: Attribute lookup failed 2", __func__);
                goto put_err_out;
        }

        /*
         * Check whether attribute is already single in this MFT record.
         * 8 added for the attribute terminator.
         */
        if (le32_to_cpu(ctx->mrec->bytes_in_use) ==
            le16_to_cpu(ctx->mrec->attrs_offset) + le32_to_cpu(ctx->attr->length) + 8) {
                err = -ENOSPC;
                ntfs_debug("MFT record is filled with one attribute\n");
                goto put_err_out;
        }

        /* Add attribute list if not present. */
        if (!NInoAttrList(base_ni)) {
                ntfs_attr_put_search_ctx(ctx);
                err = ntfs_inode_add_attrlist(base_ni);
                if (err)
                        return err;
                goto attr_resize_again;
        }

        /* Allocate new mft record. */
        err = ntfs_mft_record_alloc(base_ni->vol, 0, &ext_ni, base_ni, NULL);
        if (err) {
                ntfs_error(sb, "Couldn't allocate MFT record");
                goto put_err_out;
        }
        unmap_mft_record(ext_ni);

        /* Move attribute to it. */
        err = ntfs_attr_record_move_to(ctx, ext_ni);
        if (err) {
                ntfs_error(sb, "Couldn't move attribute to new MFT record");
                err = -ENOMEM;
                goto put_err_out;
        }

        err = ntfs_attrlist_update(base_ni);
        if (err < 0)
                goto put_err_out;

        ntfs_attr_put_search_ctx(ctx);
        /* Try to perform resize once again. */
        goto attr_resize_again;

resize_done:
        /*
         * Set the inode (and its base inode if it exists) dirty so it is
         * written out later.
         */
        mark_mft_record_dirty(ctx->ntfs_ino);
        ntfs_attr_put_search_ctx(ctx);
        return 0;

put_err_out:
        ntfs_attr_put_search_ctx(ctx);
        return err;
}

int __ntfs_attr_truncate_vfs(struct ntfs_inode *ni, const s64 newsize,
                const s64 i_size)
{
        int err = 0;

        if (newsize < 0 ||
            (ni->mft_no == FILE_MFT && ni->type == AT_DATA)) {
                ntfs_debug("Invalid arguments passed.\n");
                return -EINVAL;
        }

        ntfs_debug("Entering for inode 0x%llx, attr 0x%x, size %lld\n",
                        (unsigned long long)ni->mft_no, ni->type, newsize);

        if (NInoNonResident(ni)) {
                if (newsize > i_size) {
                        down_write(&ni->runlist.lock);
                        err = ntfs_non_resident_attr_expand(ni, newsize, 0,
                                                            NVolDisableSparse(ni->vol) ?
                                                            HOLES_NO : HOLES_OK,
                                                            false);
                        up_write(&ni->runlist.lock);
                } else
                        err = ntfs_non_resident_attr_shrink(ni, newsize);
        } else
                err = ntfs_resident_attr_resize(ni, newsize, 0,
                                                NVolDisableSparse(ni->vol) ?
                                                HOLES_NO : HOLES_OK);
        ntfs_debug("Return status %d\n", err);
        return err;
}

int ntfs_attr_expand(struct ntfs_inode *ni, const s64 newsize, const s64 prealloc_size)
{
        int err = 0;

        if (newsize < 0 ||
            (ni->mft_no == FILE_MFT && ni->type == AT_DATA)) {
                ntfs_debug("Invalid arguments passed.\n");
                return -EINVAL;
        }

        ntfs_debug("Entering for inode 0x%llx, attr 0x%x, size %lld\n",
                        (unsigned long long)ni->mft_no, ni->type, newsize);

        if (ni->data_size == newsize) {
                ntfs_debug("Size is already ok\n");
                return 0;
        }

        /*
         * Encrypted attributes are not supported. We return access denied,
         * which is what Windows NT4 does, too.
         */
        if (NInoEncrypted(ni)) {
                pr_err("Failed to truncate encrypted attribute\n");
                return -EACCES;
        }

        if (NInoNonResident(ni)) {
                if (newsize > ni->data_size)
                        err = ntfs_non_resident_attr_expand(ni, newsize, prealloc_size,
                                                            NVolDisableSparse(ni->vol) ?
                                                            HOLES_NO : HOLES_OK, true);
        } else
                err = ntfs_resident_attr_resize(ni, newsize, prealloc_size,
                                                NVolDisableSparse(ni->vol) ?
                                                HOLES_NO : HOLES_OK);
        if (!err)
                i_size_write(VFS_I(ni), newsize);
        ntfs_debug("Return status %d\n", err);
        return err;
}

/*
 * ntfs_attr_truncate_i - resize an ntfs attribute
 * @ni:         open ntfs inode to resize
 * @newsize:    new size (in bytes) to which to resize the attribute
 * @holes:      how to create a hole if expanding
 *
 * Change the size of an open ntfs attribute @na to @newsize bytes. If the
 * attribute is made bigger and the attribute is resident the newly
 * "allocated" space is cleared and if the attribute is non-resident the
 * newly allocated space is marked as not initialised and no real allocation
 * on disk is performed.
 */
int ntfs_attr_truncate_i(struct ntfs_inode *ni, const s64 newsize, unsigned int holes)
{
        int err;

        if (newsize < 0 ||
            (ni->mft_no == FILE_MFT && ni->type == AT_DATA)) {
                ntfs_debug("Invalid arguments passed.\n");
                return -EINVAL;
        }

        ntfs_debug("Entering for inode 0x%llx, attr 0x%x, size %lld\n",
                        (unsigned long long)ni->mft_no, ni->type, newsize);

        if (ni->data_size == newsize) {
                ntfs_debug("Size is already ok\n");
                return 0;
        }

        /*
         * Encrypted attributes are not supported. We return access denied,
         * which is what Windows NT4 does, too.
         */
        if (NInoEncrypted(ni)) {
                pr_err("Failed to truncate encrypted attribute\n");
                return -EACCES;
        }

        if (NInoCompressed(ni)) {
                pr_err("Failed to truncate compressed attribute\n");
                return -EOPNOTSUPP;
        }

        if (NInoNonResident(ni)) {
                if (newsize > ni->data_size)
                        err = ntfs_non_resident_attr_expand(ni, newsize, 0, holes, true);
                else
                        err = ntfs_non_resident_attr_shrink(ni, newsize);
        } else
                err = ntfs_resident_attr_resize(ni, newsize, 0, holes);
        ntfs_debug("Return status %d\n", err);
        return err;
}

/*
 * Resize an attribute, creating a hole if relevant
 */
int ntfs_attr_truncate(struct ntfs_inode *ni, const s64 newsize)
{
        return ntfs_attr_truncate_i(ni, newsize,
                                    NVolDisableSparse(ni->vol) ?
                                    HOLES_NO : HOLES_OK);
}

int ntfs_attr_map_cluster(struct ntfs_inode *ni, s64 vcn_start, s64 *lcn_start,
                s64 *lcn_count, s64 max_clu_count, bool *balloc, bool update_mp,
                bool skip_holes)
{
        struct ntfs_volume *vol = ni->vol;
        struct ntfs_attr_search_ctx *ctx;
        struct runlist_element *rl, *rlc;
        s64 vcn = vcn_start, lcn, clu_count;
        s64 lcn_seek_from = -1;
        int err = 0;
        size_t new_rl_count;

        err = ntfs_attr_map_whole_runlist(ni);
        if (err)
                return err;

        if (NInoAttr(ni))
                ctx = ntfs_attr_get_search_ctx(ni->ext.base_ntfs_ino, NULL);
        else
                ctx = ntfs_attr_get_search_ctx(ni, NULL);
        if (!ctx) {
                ntfs_error(vol->sb, "%s: Failed to get search context", __func__);
                return -ENOMEM;
        }

        err = ntfs_attr_lookup(ni->type, ni->name, ni->name_len,
                        CASE_SENSITIVE, vcn, NULL, 0, ctx);
        if (err) {
                ntfs_error(vol->sb,
                           "ntfs_attr_lookup failed, ntfs inode(mft_no : %llu) type : 0x%x, err : %d",
                           ni->mft_no, ni->type, err);
                goto out;
        }

        rl = ntfs_attr_find_vcn_nolock(ni, vcn, ctx);
        if (IS_ERR(rl)) {
                ntfs_error(vol->sb, "Failed to find run after mapping runlist.");
                err = PTR_ERR(rl);
                goto out;
        }

        lcn = ntfs_rl_vcn_to_lcn(rl, vcn);
        clu_count = min(max_clu_count, rl->length - (vcn - rl->vcn));
        if (lcn >= LCN_HOLE) {
                if (lcn > LCN_DELALLOC ||
                    (lcn == LCN_HOLE && skip_holes)) {
                        *lcn_start = lcn;
                        *lcn_count = clu_count;
                        *balloc = false;
                        goto out;
                }
        } else {
                WARN_ON(lcn == LCN_RL_NOT_MAPPED);
                if (lcn == LCN_ENOENT)
                        err = -ENOENT;
                else
                        err = -EIO;
                goto out;
        }

        /* Search backwards to find the best lcn to start seek from. */
        rlc = rl;
        while (rlc->vcn) {
                rlc--;
                if (rlc->lcn >= 0) {
                        /*
                         * avoid fragmenting a compressed file
                         * Windows does not do that, and that may
                         * not be desirable for files which can
                         * be updated
                         */
                        if (NInoCompressed(ni))
                                lcn_seek_from = rlc->lcn + rlc->length;
                        else
                                lcn_seek_from = rlc->lcn + (vcn - rlc->vcn);
                        break;
                }
        }

        if (lcn_seek_from == -1) {
                /* Backwards search failed, search forwards. */
                rlc = rl;
                while (rlc->length) {
                        rlc++;
                        if (rlc->lcn >= 0) {
                                lcn_seek_from = rlc->lcn - (rlc->vcn - vcn);
                                if (lcn_seek_from < -1)
                                        lcn_seek_from = -1;
                                break;
                        }
                }
        }

        rlc = ntfs_cluster_alloc(vol, vcn, clu_count, lcn_seek_from, DATA_ZONE,
                        false, true, true);
        if (IS_ERR(rlc)) {
                err = PTR_ERR(rlc);
                goto out;
        }

        WARN_ON(rlc->vcn != vcn);
        lcn = rlc->lcn;
        clu_count = rlc->length;

        rl = ntfs_runlists_merge(&ni->runlist, rlc, 0, &new_rl_count);
        if (IS_ERR(rl)) {
                ntfs_error(vol->sb, "Failed to merge runlists");
                err = PTR_ERR(rl);
                if (ntfs_cluster_free_from_rl(vol, rlc))
                        ntfs_error(vol->sb, "Failed to free hot clusters.");
                kvfree(rlc);
                goto out;
        }
        ni->runlist.rl = rl;
        ni->runlist.count = new_rl_count;

        if (!update_mp) {
                u64 free = atomic64_read(&vol->free_clusters) * 100;

                do_div(free, vol->nr_clusters);
                if (free <= 5)
                        update_mp = true;
        }

        if (update_mp) {
                ntfs_attr_reinit_search_ctx(ctx);
                err = ntfs_attr_update_mapping_pairs(ni, 0);
                if (err) {
                        int err2;

                        err2 = ntfs_cluster_free(ni, vcn, clu_count, ctx);
                        if (err2 < 0)
                                ntfs_error(vol->sb,
                                           "Failed to free cluster allocation. Leaving inconstant metadata.\n");
                        goto out;
                }
        } else {
                VFS_I(ni)->i_blocks += clu_count << (vol->cluster_size_bits - 9);
                NInoSetRunlistDirty(ni);
                mark_mft_record_dirty(ni);
        }

        *lcn_start = lcn;
        *lcn_count = clu_count;
        *balloc = true;
out:
        ntfs_attr_put_search_ctx(ctx);
        return err;
}

/*
 * ntfs_attr_rm - remove attribute from ntfs inode
 * @ni:         opened ntfs attribute to delete
 *
 * Remove attribute and all it's extents from ntfs inode. If attribute was non
 * resident also free all clusters allocated by attribute.
 */
int ntfs_attr_rm(struct ntfs_inode *ni)
{
        struct ntfs_attr_search_ctx *ctx;
        int err = 0, ret = 0;
        struct ntfs_inode *base_ni;
        struct super_block *sb = ni->vol->sb;

        if (NInoAttr(ni))
                base_ni = ni->ext.base_ntfs_ino;
        else
                base_ni = ni;

        ntfs_debug("Entering for inode 0x%llx, attr 0x%x.\n",
                        (long long) ni->mft_no, ni->type);

        /* Free cluster allocation. */
        if (NInoNonResident(ni)) {
                struct ntfs_attr_search_ctx *ctx;

                err = ntfs_attr_map_whole_runlist(ni);
                if (err)
                        return err;
                ctx = ntfs_attr_get_search_ctx(ni, NULL);
                if (!ctx) {
                        ntfs_error(sb, "%s: Failed to get search context", __func__);
                        return -ENOMEM;
                }

                ret = ntfs_cluster_free(ni, 0, -1, ctx);
                if (ret < 0)
                        ntfs_error(sb,
                                "Failed to free cluster allocation. Leaving inconstant metadata.\n");
                ntfs_attr_put_search_ctx(ctx);
        }

        /* Search for attribute extents and remove them all. */
        ctx = ntfs_attr_get_search_ctx(base_ni, NULL);
        if (!ctx) {
                ntfs_error(sb, "%s: Failed to get search context", __func__);
                return -ENOMEM;
        }
        while (!(err = ntfs_attr_lookup(ni->type, ni->name, ni->name_len,
                                CASE_SENSITIVE, 0, NULL, 0, ctx))) {
                err = ntfs_attr_record_rm(ctx);
                if (err) {
                        ntfs_error(sb,
                                "Failed to remove attribute extent. Leaving inconstant metadata.\n");
                        ret = err;
                }
                ntfs_attr_reinit_search_ctx(ctx);
        }
        ntfs_attr_put_search_ctx(ctx);
        if (err != -ENOENT) {
                ntfs_error(sb, "Attribute lookup failed. Probably leaving inconstant metadata.\n");
                ret = err;
        }

        return ret;
}

int ntfs_attr_exist(struct ntfs_inode *ni, const __le32 type, __le16 *name,
                u32 name_len)
{
        struct ntfs_attr_search_ctx *ctx;
        int ret;

        ntfs_debug("Entering\n");

        ctx = ntfs_attr_get_search_ctx(ni, NULL);
        if (!ctx) {
                ntfs_error(ni->vol->sb, "%s: Failed to get search context",
                                __func__);
                return 0;
        }

        ret = ntfs_attr_lookup(type, name, name_len, CASE_SENSITIVE,
                        0, NULL, 0, ctx);
        ntfs_attr_put_search_ctx(ctx);

        return !ret;
}

int ntfs_attr_remove(struct ntfs_inode *ni, const __le32 type, __le16 *name,
                u32 name_len)
{
        int err;
        struct inode *attr_vi;
        struct ntfs_inode *attr_ni;

        ntfs_debug("Entering\n");

        if (!ni)
                return -EINVAL;

        attr_vi = ntfs_attr_iget(VFS_I(ni), type, name, name_len);
        if (IS_ERR(attr_vi)) {
                err = PTR_ERR(attr_vi);
                ntfs_error(ni->vol->sb, "Failed to open attribute 0x%02x of inode 0x%llx",
                                type, (unsigned long long)ni->mft_no);
                return err;
        }
        attr_ni = NTFS_I(attr_vi);

        err = ntfs_attr_rm(attr_ni);
        if (err)
                ntfs_error(ni->vol->sb, "Failed to remove attribute 0x%02x of inode 0x%llx",
                                type, (unsigned long long)ni->mft_no);
        iput(attr_vi);
        return err;
}

/*
 * ntfs_attr_readall - read the entire data from an ntfs attribute
 * @ni:         open ntfs inode in which the ntfs attribute resides
 * @type:       attribute type
 * @name:       attribute name in little endian Unicode or AT_UNNAMED or NULL
 * @name_len:   length of attribute @name in Unicode characters (if @name given)
 * @data_size:  if non-NULL then store here the data size
 *
 * This function will read the entire content of an ntfs attribute.
 * If @name is AT_UNNAMED then look specifically for an unnamed attribute.
 * If @name is NULL then the attribute could be either named or not.
 * In both those cases @name_len is not used at all.
 *
 * On success a buffer is allocated with the content of the attribute
 * and which needs to be freed when it's not needed anymore. If the
 * @data_size parameter is non-NULL then the data size is set there.
 */
void *ntfs_attr_readall(struct ntfs_inode *ni, const __le32 type,
                __le16 *name, u32 name_len, s64 *data_size)
{
        struct ntfs_inode *bmp_ni;
        struct inode *bmp_vi;
        void *data, *ret = NULL;
        s64 size;
        struct super_block *sb = ni->vol->sb;

        ntfs_debug("Entering\n");

        bmp_vi = ntfs_attr_iget(VFS_I(ni), type, name, name_len);
        if (IS_ERR(bmp_vi)) {
                ntfs_debug("ntfs_attr_iget failed");
                goto err_exit;
        }
        bmp_ni = NTFS_I(bmp_vi);

        if (bmp_ni->data_size > NTFS_ATTR_READALL_MAX_SIZE &&
                (bmp_ni->type != AT_BITMAP ||
                bmp_ni->data_size > ((ni->vol->nr_clusters + 7) >> 3))) {
                ntfs_error(sb, "Invalid attribute data size");
                goto out;
        }

        data = kvmalloc(bmp_ni->data_size, GFP_NOFS);
        if (!data)
                goto out;

        size = ntfs_inode_attr_pread(VFS_I(bmp_ni), 0, bmp_ni->data_size,
                        (u8 *)data);
        if (size != bmp_ni->data_size) {
                ntfs_error(sb, "ntfs_attr_pread failed");
                kvfree(data);
                goto out;
        }
        ret = data;
        if (data_size)
                *data_size = size;
out:
        iput(bmp_vi);
err_exit:
        ntfs_debug("\n");
        return ret;
}

int ntfs_non_resident_attr_insert_range(struct ntfs_inode *ni, s64 start_vcn, s64 len)
{
        struct ntfs_volume *vol = ni->vol;
        struct runlist_element *hole_rl, *rl;
        struct ntfs_attr_search_ctx *ctx;
        int ret;
        size_t new_rl_count;

        if (NInoAttr(ni) || ni->type != AT_DATA)
                return -EOPNOTSUPP;
        if (start_vcn > ntfs_bytes_to_cluster(vol, ni->allocated_size))
                return -EINVAL;

        hole_rl = kmalloc(sizeof(*hole_rl) * 2, GFP_NOFS);
        if (!hole_rl)
                return -ENOMEM;
        hole_rl[0].vcn = start_vcn;
        hole_rl[0].lcn = LCN_HOLE;
        hole_rl[0].length = len;
        hole_rl[1].vcn = start_vcn + len;
        hole_rl[1].lcn = LCN_ENOENT;
        hole_rl[1].length = 0;

        down_write(&ni->runlist.lock);
        ret = ntfs_attr_map_whole_runlist(ni);
        if (ret) {
                up_write(&ni->runlist.lock);
                kfree(hole_rl);
                return ret;
        }

        rl = ntfs_rl_find_vcn_nolock(ni->runlist.rl, start_vcn);
        if (!rl) {
                up_write(&ni->runlist.lock);
                kfree(hole_rl);
                return -EIO;
        }

        rl = ntfs_rl_insert_range(ni->runlist.rl, (int)ni->runlist.count,
                                  hole_rl, 1, &new_rl_count);
        if (IS_ERR(rl)) {
                up_write(&ni->runlist.lock);
                kfree(hole_rl);
                return PTR_ERR(rl);
        }
        ni->runlist.rl =  rl;
        ni->runlist.count = new_rl_count;

        ni->allocated_size += ntfs_cluster_to_bytes(vol, len);
        ni->data_size += ntfs_cluster_to_bytes(vol, len);
        if (ntfs_cluster_to_bytes(vol, start_vcn) < ni->initialized_size)
                ni->initialized_size += ntfs_cluster_to_bytes(vol, len);
        ret = ntfs_attr_update_mapping_pairs(ni, 0);
        up_write(&ni->runlist.lock);
        if (ret)
                return ret;

        ctx = ntfs_attr_get_search_ctx(ni, NULL);
        if (!ctx) {
                ret = -ENOMEM;
                return ret;
        }

        ret = ntfs_attr_lookup(ni->type, ni->name, ni->name_len, CASE_SENSITIVE,
                               0, NULL, 0, ctx);
        if (ret) {
                ntfs_attr_put_search_ctx(ctx);
                return ret;
        }

        ctx->attr->data.non_resident.data_size = cpu_to_le64(ni->data_size);
        ctx->attr->data.non_resident.initialized_size = cpu_to_le64(ni->initialized_size);
        if (ni->type == AT_DATA && ni->name == AT_UNNAMED)
                NInoSetFileNameDirty(ni);
        mark_mft_record_dirty(ctx->ntfs_ino);
        ntfs_attr_put_search_ctx(ctx);
        return ret;
}

int ntfs_non_resident_attr_collapse_range(struct ntfs_inode *ni, s64 start_vcn, s64 len)
{
        struct ntfs_volume *vol = ni->vol;
        struct runlist_element *punch_rl, *rl;
        struct ntfs_attr_search_ctx *ctx = NULL;
        s64 end_vcn;
        int dst_cnt;
        int ret;
        size_t new_rl_cnt;

        if (NInoAttr(ni) || ni->type != AT_DATA)
                return -EOPNOTSUPP;

        end_vcn = ntfs_bytes_to_cluster(vol, ni->allocated_size);
        if (start_vcn >= end_vcn)
                return -EINVAL;

        down_write(&ni->runlist.lock);
        ret = ntfs_attr_map_whole_runlist(ni);
        if (ret) {
                up_write(&ni->runlist.lock);
                return ret;
        }

        len = min(len, end_vcn - start_vcn);
        for (rl = ni->runlist.rl, dst_cnt = 0; rl && rl->length; rl++)
                dst_cnt++;
        rl = ntfs_rl_find_vcn_nolock(ni->runlist.rl, start_vcn);
        if (!rl) {
                up_write(&ni->runlist.lock);
                return -EIO;
        }

        rl = ntfs_rl_collapse_range(ni->runlist.rl, dst_cnt + 1,
                                    start_vcn, len, &punch_rl, &new_rl_cnt);
        if (IS_ERR(rl)) {
                up_write(&ni->runlist.lock);
                return PTR_ERR(rl);
        }
        ni->runlist.rl = rl;
        ni->runlist.count = new_rl_cnt;

        ni->allocated_size -= ntfs_cluster_to_bytes(vol, len);
        if (ni->data_size > ntfs_cluster_to_bytes(vol, start_vcn)) {
                if (ni->data_size > ntfs_cluster_to_bytes(vol, (start_vcn + len)))
                        ni->data_size -= ntfs_cluster_to_bytes(vol, len);
                else
                        ni->data_size = ntfs_cluster_to_bytes(vol, start_vcn);
        }
        if (ni->initialized_size > ntfs_cluster_to_bytes(vol, start_vcn)) {
                if (ni->initialized_size >
                    ntfs_cluster_to_bytes(vol, start_vcn + len))
                        ni->initialized_size -= ntfs_cluster_to_bytes(vol, len);
                else
                        ni->initialized_size = ntfs_cluster_to_bytes(vol, start_vcn);
        }

        if (ni->allocated_size > 0) {
                ret = ntfs_attr_update_mapping_pairs(ni, 0);
                if (ret) {
                        up_write(&ni->runlist.lock);
                        goto out_rl;
                }
        }
        up_write(&ni->runlist.lock);

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

        ret = ntfs_attr_lookup(ni->type, ni->name, ni->name_len, CASE_SENSITIVE,
                               0, NULL, 0, ctx);
        if (ret)
                goto out_ctx;

        ctx->attr->data.non_resident.data_size = cpu_to_le64(ni->data_size);
        ctx->attr->data.non_resident.initialized_size = cpu_to_le64(ni->initialized_size);
        if (ni->allocated_size == 0)
                ntfs_attr_make_resident(ni, ctx);
        mark_mft_record_dirty(ctx->ntfs_ino);

        ret = ntfs_cluster_free_from_rl(vol, punch_rl);
        if (ret)
                ntfs_error(vol->sb, "Freeing of clusters failed");
out_ctx:
        if (ctx)
                ntfs_attr_put_search_ctx(ctx);
out_rl:
        kvfree(punch_rl);
        mark_mft_record_dirty(ni);
        return ret;
}

int ntfs_non_resident_attr_punch_hole(struct ntfs_inode *ni, s64 start_vcn, s64 len)
{
        struct ntfs_volume *vol = ni->vol;
        struct runlist_element *punch_rl, *rl;
        s64 end_vcn;
        int dst_cnt;
        int ret;
        size_t new_rl_count;

        if (NInoAttr(ni) || ni->type != AT_DATA)
                return -EOPNOTSUPP;

        end_vcn = ntfs_bytes_to_cluster(vol, ni->allocated_size);
        if (start_vcn >= end_vcn)
                return -EINVAL;

        down_write(&ni->runlist.lock);
        ret = ntfs_attr_map_whole_runlist(ni);
        if (ret) {
                up_write(&ni->runlist.lock);
                return ret;
        }

        len = min(len, end_vcn - start_vcn + 1);
        for (rl = ni->runlist.rl, dst_cnt = 0; rl && rl->length; rl++)
                dst_cnt++;
        rl = ntfs_rl_find_vcn_nolock(ni->runlist.rl, start_vcn);
        if (!rl) {
                up_write(&ni->runlist.lock);
                return -EIO;
        }

        rl = ntfs_rl_punch_hole(ni->runlist.rl, dst_cnt + 1,
                                start_vcn, len, &punch_rl, &new_rl_count);
        if (IS_ERR(rl)) {
                up_write(&ni->runlist.lock);
                return PTR_ERR(rl);
        }
        ni->runlist.rl = rl;
        ni->runlist.count = new_rl_count;

        ret = ntfs_attr_update_mapping_pairs(ni, 0);
        up_write(&ni->runlist.lock);
        if (ret) {
                kvfree(punch_rl);
                return ret;
        }

        ret = ntfs_cluster_free_from_rl(vol, punch_rl);
        if (ret)
                ntfs_error(vol->sb, "Freeing of clusters failed");

        kvfree(punch_rl);
        mark_mft_record_dirty(ni);
        return ret;
}

int ntfs_attr_fallocate(struct ntfs_inode *ni, loff_t start, loff_t byte_len, bool keep_size)
{
        struct ntfs_volume *vol = ni->vol;
        struct mft_record *mrec;
        struct ntfs_attr_search_ctx *ctx;
        s64 old_data_size;
        s64 vcn_start, vcn_end, vcn_uninit, vcn, try_alloc_cnt;
        s64 lcn, alloc_cnt;
        s64 rl_lcn, rl_length, rl_vcn;
        int err = 0;
        struct runlist_element *rl;
        bool balloc;

        if (NInoAttr(ni) || ni->type != AT_DATA)
                return -EINVAL;

        if (NInoNonResident(ni) && !NInoFullyMapped(ni)) {
                down_write(&ni->runlist.lock);
                err = ntfs_attr_map_whole_runlist(ni);
                up_write(&ni->runlist.lock);
                if (err)
                        return err;
        }

        mutex_lock_nested(&ni->mrec_lock, NTFS_INODE_MUTEX_NORMAL);
        mrec = map_mft_record(ni);
        if (IS_ERR(mrec)) {
                mutex_unlock(&ni->mrec_lock);
                return PTR_ERR(mrec);
        }

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

        err = ntfs_attr_lookup(AT_DATA, AT_UNNAMED, 0, 0, 0, NULL, 0, ctx);
        if (err) {
                err = -EIO;
                goto out_unmap;
        }

        old_data_size = ni->data_size;
        if (start + byte_len > ni->data_size) {
                err = ntfs_attr_truncate(ni, start + byte_len);
                if (err)
                        goto out_unmap;
                if (keep_size) {
                        ntfs_attr_reinit_search_ctx(ctx);
                        err = ntfs_attr_lookup(AT_DATA, AT_UNNAMED, 0, 0, 0, NULL, 0, ctx);
                        if (err) {
                                err = -EIO;
                                goto out_unmap;
                        }
                        ni->data_size = old_data_size;
                        if (NInoNonResident(ni))
                                ctx->attr->data.non_resident.data_size =
                                        cpu_to_le64(old_data_size);
                        else
                                ctx->attr->data.resident.value_length =
                                        cpu_to_le32((u32)old_data_size);
                        mark_mft_record_dirty(ni);
                }
        }

        ntfs_attr_put_search_ctx(ctx);
        unmap_mft_record(ni);
        mutex_unlock(&ni->mrec_lock);

        if (!NInoNonResident(ni))
                goto out;

        vcn_start = (s64)ntfs_bytes_to_cluster(vol, start);
        vcn_end = (s64)ntfs_bytes_to_cluster(vol,
                        round_up(start + byte_len, vol->cluster_size));
        vcn_uninit = (s64)ntfs_bytes_to_cluster(vol,
                        round_up(ni->initialized_size, vol->cluster_size));
        vcn_uninit = min_t(s64, vcn_uninit, vcn_end);

        /*
         * we have to allocate clusters for holes and delayed within initialized_size,
         * and zero out the clusters only for the holes.
         */
        vcn = vcn_start;
        while (vcn < vcn_uninit) {
                down_read(&ni->runlist.lock);
                rl = ntfs_attr_find_vcn_nolock(ni, vcn, NULL);
                if (IS_ERR(rl)) {
                        up_read(&ni->runlist.lock);
                        err = PTR_ERR(rl);
                        goto out;
                }
                rl_lcn = rl->lcn;
                rl_length = rl->length;
                rl_vcn = rl->vcn;
                up_read(&ni->runlist.lock);

                if (rl_lcn > 0) {
                        vcn += rl_length - (vcn - rl_vcn);
                } else if (rl_lcn == LCN_DELALLOC || rl_lcn == LCN_HOLE) {
                        try_alloc_cnt = min(rl_length - (vcn - rl_vcn),
                                            vcn_uninit - vcn);

                        if (rl_lcn == LCN_DELALLOC) {
                                vcn += try_alloc_cnt;
                                continue;
                        }

                        while (try_alloc_cnt > 0) {
                                mutex_lock_nested(&ni->mrec_lock, NTFS_INODE_MUTEX_NORMAL);
                                down_write(&ni->runlist.lock);
                                err = ntfs_attr_map_cluster(ni, vcn, &lcn, &alloc_cnt,
                                                            try_alloc_cnt, &balloc, false, false);
                                up_write(&ni->runlist.lock);
                                mutex_unlock(&ni->mrec_lock);
                                if (err)
                                        goto out;

                                if (balloc) {
                                        err = ntfs_dio_zero_range(VFS_I(ni),
                                                                  lcn << vol->cluster_size_bits,
                                                                  alloc_cnt <<
                                                                  vol->cluster_size_bits);
                                        if (err > 0)
                                                goto out;
                                }

                                if (signal_pending(current))
                                        goto out;

                                vcn += alloc_cnt;
                                try_alloc_cnt -= alloc_cnt;
                        }
                } else {
                        err = -EIO;
                        goto out;
                }
        }

        /* allocate clusters outside of initialized_size */
        try_alloc_cnt = vcn_end - vcn;
        while (try_alloc_cnt > 0) {
                mutex_lock_nested(&ni->mrec_lock, NTFS_INODE_MUTEX_NORMAL);
                down_write(&ni->runlist.lock);
                err = ntfs_attr_map_cluster(ni, vcn, &lcn, &alloc_cnt,
                                            try_alloc_cnt, &balloc, false, false);
                up_write(&ni->runlist.lock);
                mutex_unlock(&ni->mrec_lock);
                if (err || signal_pending(current))
                        goto out;

                vcn += alloc_cnt;
                try_alloc_cnt -= alloc_cnt;
                cond_resched();
        }

        if (NInoRunlistDirty(ni)) {
                mutex_lock_nested(&ni->mrec_lock, NTFS_INODE_MUTEX_NORMAL);
                down_write(&ni->runlist.lock);
                err = ntfs_attr_update_mapping_pairs(ni, 0);
                if (err)
                        ntfs_error(ni->vol->sb, "Updating mapping pairs failed");
                else
                        NInoClearRunlistDirty(ni);
                up_write(&ni->runlist.lock);
                mutex_unlock(&ni->mrec_lock);
        }
        return err;
out_unmap:
        if (ctx)
                ntfs_attr_put_search_ctx(ctx);
        unmap_mft_record(ni);
        mutex_unlock(&ni->mrec_lock);
out:
        return err >= 0 ? 0 : err;
}