sys/ntfs/ntfs_subr.c

root/sys/ntfs/ntfs_subr.c
/*      $OpenBSD: ntfs_subr.c,v 1.53 2025/01/13 13:58:41 claudio Exp $  */
/*      $NetBSD: ntfs_subr.c,v 1.4 2003/04/10 21:37:32 jdolecek Exp $   */

/*-
 * Copyright (c) 1998, 1999 Semen Ustimenko (semenu@FreeBSD.org)
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 *
 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 * SUCH DAMAGE.
 *
 *      Id: ntfs_subr.c,v 1.4 1999/05/12 09:43:01 semenu Exp
 */

#include <sys/param.h>
#include <sys/systm.h>
#include <sys/namei.h>
#include <sys/kernel.h>
#include <sys/vnode.h>
#include <sys/lock.h>
#include <sys/mount.h>
#include <sys/buf.h>
#include <sys/malloc.h>
#include <sys/rwlock.h>
#include <sys/specdev.h>

/* #define NTFS_DEBUG 1 */
#include <ntfs/ntfs.h>
#include <ntfs/ntfsmount.h>
#include <ntfs/ntfs_inode.h>
#include <ntfs/ntfs_vfsops.h>
#include <ntfs/ntfs_subr.h>
#include <ntfs/ntfs_compr.h>
#include <ntfs/ntfs_ihash.h>

#if defined(NTFS_DEBUG)
int ntfs_debug = NTFS_DEBUG;
#endif

/* Local struct used in ntfs_ntlookupfile() */
struct ntfs_lookup_ctx {
        u_int32_t       aoff;
        u_int32_t       rdsize;
        cn_t            cn;
        struct ntfs_lookup_ctx *prev;
};

int ntfs_ntlookupattr(struct ntfsmount *, const char *, int, int *, char **);
int ntfs_findvattr(struct ntfsmount *, struct ntnode *, struct ntvattr **, struct ntvattr **, u_int32_t, const char *, size_t, cn_t);
int ntfs_uastricmp(struct ntfsmount *, const wchar *, size_t, const char *, size_t);
int ntfs_uastrcmp(struct ntfsmount *, const wchar *, size_t, const char *, size_t);

/* table for mapping Unicode chars into uppercase; it's filled upon first
 * ntfs mount, freed upon last ntfs umount */
static wchar *ntfs_toupper_tab;
#define NTFS_U28(ch)            ((((ch) & 0xE0) == 0) ? '_' : (ch) & 0xFF)
#define NTFS_TOUPPER(ch)        (ntfs_toupper_tab[(unsigned char)(ch)])
struct rwlock ntfs_toupper_lock = RWLOCK_INITIALIZER("ntfs_toupper");
static signed int ntfs_toupper_usecount;

/* support macro for ntfs_ntvattrget() */
#define NTFS_AALPCMP(aalp,type,name,namelen) (                          \
  (aalp->al_type == type) && (aalp->al_namelen == namelen) &&           \
  !ntfs_uastrcmp(ntmp, aalp->al_name,aalp->al_namelen,name,namelen) )

/*
 * 
 */
int
ntfs_ntvattrrele(struct ntvattr *vap)
{
        DPRINTF("ntfs_ntvattrrele: ino: %u, type: 0x%x\n",
            vap->va_ip->i_number, vap->va_type);

        ntfs_ntrele(vap->va_ip);

        return (0);
}

/*
 * find the attribute in the ntnode
 */
int
ntfs_findvattr(struct ntfsmount *ntmp, struct ntnode *ip,
    struct ntvattr **lvapp, struct ntvattr **vapp, u_int32_t type,
    const char *name, size_t namelen, cn_t vcn)
{
        int error;
        struct ntvattr *vap;

        if((ip->i_flag & IN_LOADED) == 0) {
                DPRINTF("ntfs_findvattr: node not loaded, ino: %u\n",
                    ip->i_number);
                error = ntfs_loadntnode(ntmp,ip);
                if (error) {
                        printf("ntfs_findvattr: FAILED TO LOAD INO: %d\n",
                               ip->i_number);
                        return (error);
                }
        } else {
                /* Update LRU loaded list. */
                TAILQ_REMOVE(&ntmp->ntm_ntnodeq, ip, i_loaded);
                TAILQ_INSERT_HEAD(&ntmp->ntm_ntnodeq, ip, i_loaded);
        }

        *lvapp = NULL;
        *vapp = NULL;
        LIST_FOREACH(vap, &ip->i_valist, va_list) {
                DDPRINTF("ntfs_findvattr: type: 0x%x, vcn: %llu - %llu\n",
                    vap->va_type, vap->va_vcnstart, vap->va_vcnend);
                if ((vap->va_type == type) &&
                    (vap->va_vcnstart <= vcn) && (vap->va_vcnend >= vcn) &&
                    (vap->va_namelen == namelen) &&
                    (strncmp(name, vap->va_name, namelen) == 0)) {
                        *vapp = vap;
                        ntfs_ntref(vap->va_ip);
                        return (0);
                }
                if (vap->va_type == NTFS_A_ATTRLIST)
                        *lvapp = vap;
        }

        return (-1);
}

/*
 * Search attribute specified in ntnode (load ntnode if necessary).
 * If not found but ATTR_A_ATTRLIST present, read it in and search through.
 * VOP_VGET node needed, and lookup through its ntnode (load if necessary).
 *
 * ntnode should be locked
 */
int
ntfs_ntvattrget(struct ntfsmount *ntmp, struct ntnode *ip, u_int32_t type,
    const char *name, cn_t vcn, struct ntvattr **vapp)
{
        struct ntvattr *lvap = NULL;
        struct attr_attrlist *aalp;
        struct attr_attrlist *nextaalp;
        struct vnode   *newvp;
        struct ntnode  *newip;
        caddr_t         alpool;
        size_t          namelen, len;
        int             error;

        *vapp = NULL;

        if (name) {
                DPRINTF("ntfs_ntvattrget: ino: %u, type: 0x%x, name: %s, "
                    "vcn: %llu\n", ip->i_number, type, name, vcn);
                namelen = strlen(name);
        } else {
                DPRINTF("ntfs_ntvattrget: ino: %u, type: 0x%x, vcn: %llu\n",
                    ip->i_number, type, vcn);
                name = "";
                namelen = 0;
        }

        error = ntfs_findvattr(ntmp, ip, &lvap, vapp, type, name, namelen, vcn);
        if (error >= 0)
                return (error);

        if (!lvap) {
                DPRINTF("ntfs_ntvattrget: UNEXISTED ATTRIBUTE: ino: %u, "
                    "type: 0x%x, name: %s, vcn: %llu\n", ip->i_number, type,
                    name, vcn);
                return (ENOENT);
        }
        /* Scan $ATTRIBUTE_LIST for requested attribute */
        len = lvap->va_datalen;
        alpool = malloc(len, M_TEMP, M_WAITOK);
        error = ntfs_readntvattr_plain(ntmp, ip, lvap, 0, len, alpool, &len,
                        NULL);
        if (error)
                goto out;

        aalp = (struct attr_attrlist *) alpool;
        nextaalp = NULL;

        for(; len > 0; aalp = nextaalp) {
                DPRINTF("ntfs_ntvattrget: attrlist: ino: %u, attr: 0x%x, "
                    "vcn: %llu\n", aalp->al_inumber, aalp->al_type,
                    aalp->al_vcnstart);

                if (len > aalp->reclen) {
                        nextaalp = NTFS_NEXTREC(aalp, struct attr_attrlist *);
                } else {
                        nextaalp = NULL;
                }
                len -= aalp->reclen;

                if (!NTFS_AALPCMP(aalp, type, name, namelen) ||
                    (nextaalp && (nextaalp->al_vcnstart <= vcn) &&
                     NTFS_AALPCMP(nextaalp, type, name, namelen)))
                        continue;

                DPRINTF("ntfs_ntvattrget: attribute in ino: %u\n",
                    aalp->al_inumber);

                /* this is not a main record, so we can't use just plain
                   vget() */
                error = ntfs_vgetex(ntmp->ntm_mountp, aalp->al_inumber,
                                NTFS_A_DATA, NULL, LK_EXCLUSIVE,
                                VG_EXT, &newvp);
                if (error) {
                        printf("ntfs_ntvattrget: CAN'T VGET INO: %d\n",
                               aalp->al_inumber);
                        goto out;
                }
                newip = VTONT(newvp);
                /* XXX have to lock ntnode */
                error = ntfs_findvattr(ntmp, newip, &lvap, vapp,
                                type, name, namelen, vcn);
                vput(newvp);
                if (error == 0)
                        goto out;
                printf("ntfs_ntvattrget: ATTRLIST ERROR.\n");
                break;
        }
        error = ENOENT;

        DPRINTF("ntfs_ntvattrget: UNEXISTED ATTRIBUTE: ino: %u, type: 0x%x, "
            "name: %.*s, vcn: %llu\n", ip->i_number, type,
            (unsigned int)namelen, name, vcn);
out:
        free(alpool, M_TEMP, 0);
        return (error);
}

/*
 * Read ntnode from disk, make ntvattr list.
 *
 * ntnode should be locked
 */
int
ntfs_loadntnode(struct ntfsmount *ntmp, struct ntnode *ip)
{
        struct ntnode   *oip;
        struct ntvattr  *vap;
        struct filerec  *mfrp;
        struct attr     *ap;
        daddr_t         bn;
        int             error,off;
 
        DPRINTF("ntfs_loadntnode: loading ino: %u\n", ip->i_number);
 
        KASSERT((ip->i_flag & IN_LOADED) == 0);

        if (ntmp->ntm_ntnodes >= LOADED_NTNODE_HI) {
                oip = TAILQ_LAST(&ntmp->ntm_ntnodeq, ntnodeq);
                TAILQ_REMOVE(&ntmp->ntm_ntnodeq, oip, i_loaded);
                ntmp->ntm_ntnodes--;

                DPRINTF("ntfs_loadntnode: unloading ino: %u\n", oip->i_number);

                KASSERT((oip->i_flag & IN_LOADED));
                oip->i_flag &= ~IN_LOADED;
                while ((vap = LIST_FIRST(&oip->i_valist)) != NULL) {
                        LIST_REMOVE(vap, va_list);
                        ntfs_freentvattr(vap);
                }
        }

        mfrp = malloc(ntfs_bntob(ntmp->ntm_bpmftrec), M_TEMP, M_WAITOK);
 
        if (ip->i_number < NTFS_SYSNODESNUM) {
                struct buf     *bp;

                DPRINTF("ntfs_loadntnode: read system node\n");

                bn = ntfs_cntobn(ntmp->ntm_mftcn) +
                        ntmp->ntm_bpmftrec * ip->i_number;

                error = bread(ntmp->ntm_devvp, bn,
                    ntfs_bntob(ntmp->ntm_bpmftrec), &bp);
                if (error) {
                        printf("ntfs_loadntnode: BREAD FAILED\n");
                        brelse(bp);
                        goto out;
                }
                memcpy(mfrp, bp->b_data, ntfs_bntob(ntmp->ntm_bpmftrec));
                brelse(bp);
        } else {
                struct vnode   *vp;

                vp = ntmp->ntm_sysvn[NTFS_MFTINO];
                error = ntfs_readattr(ntmp, VTONT(vp), NTFS_A_DATA, NULL,
                               ip->i_number * ntfs_bntob(ntmp->ntm_bpmftrec),
                               ntfs_bntob(ntmp->ntm_bpmftrec), mfrp, NULL);
                if (error) {
                        printf("ntfs_loadntnode: ntfs_readattr failed\n");
                        goto out;
                }
        }

        /* Check if magic and fixups are correct */
        error = ntfs_procfixups(ntmp, NTFS_FILEMAGIC, (caddr_t)mfrp,
                                ntfs_bntob(ntmp->ntm_bpmftrec));
        if (error) {
                printf("ntfs_loadntnode: BAD MFT RECORD %d\n",
                       (u_int32_t) ip->i_number);
                goto out;
        }

        DPRINTF("ntfs_loadntnode: load attrs for ino: %u\n", ip->i_number);
        off = mfrp->fr_attroff;
        ap = (struct attr *) ((caddr_t)mfrp + off);

        LIST_INIT(&ip->i_valist);
        
        while (ap->a_hdr.a_type != -1) {
                error = ntfs_attrtontvattr(ntmp, &vap, ap);
                if (error)
                        break;
                vap->va_ip = ip;

                LIST_INSERT_HEAD(&ip->i_valist, vap, va_list);

                off += ap->a_hdr.reclen;
                ap = (struct attr *) ((caddr_t)mfrp + off);
        }
        if (error) {
                printf("ntfs_loadntnode: failed to load attr ino: %d\n",
                       ip->i_number);
                goto out;
        }

        ip->i_mainrec = mfrp->fr_mainrec;
        ip->i_nlink = mfrp->fr_nlink;
        ip->i_frflag = mfrp->fr_flags;

        ip->i_flag |= IN_LOADED;

        /* Add to loaded list. */
        TAILQ_INSERT_HEAD(&ntmp->ntm_ntnodeq, ip, i_loaded);
        ntmp->ntm_ntnodes++;

out:
        free(mfrp, M_TEMP, 0);
        return (error);
}

/*
 * Routine locks ntnode and increase usecount, just opposite of
 * ntfs_ntput().
 */
int
ntfs_ntget(struct ntnode *ip)
{
        DPRINTF("ntfs_ntget: get ntnode %u: %p, usecount: %d\n",
            ip->i_number, ip, ip->i_usecount);

        ip->i_usecount++;

        rw_enter_write(&ip->i_lock);

        return 0;
}

/*
 * Routine search ntnode in hash, if found: lock, inc usecount and return.
 * If not in hash allocate structure for ntnode, prefill it, lock,
 * inc count and return.
 *
 * ntnode returned locked
 */
int
ntfs_ntlookup(struct ntfsmount *ntmp, ntfsino_t ino, struct ntnode **ipp)
{
        struct ntnode  *ip;

        DPRINTF("ntfs_ntlookup: looking for ntnode %u\n", ino);

 retry:
        if ((ip = ntfs_nthashlookup(ntmp->ntm_dev, ino)) != NULL) {
                ntfs_ntget(ip);
                DPRINTF("ntfs_ntlookup: ntnode %u: %p, usecount: %d\n",
                    ino, ip, ip->i_usecount);
                *ipp = ip;
                return (0);
        }

        ip = malloc(sizeof(*ip), M_NTFSNTNODE, M_WAITOK | M_ZERO);
        DDPRINTF("ntfs_ntlookup: allocating ntnode: %u: %p\n", ino, ip);

        /* Generic initialization */
        ip->i_devvp = ntmp->ntm_devvp;
        ip->i_dev = ntmp->ntm_dev;
        ip->i_number = ino;
        ip->i_mp = ntmp;

        LIST_INIT(&ip->i_fnlist);
        LIST_INIT(&ip->i_valist);
        vref(ip->i_devvp);

        /* init lock and lock the newborn ntnode */
        rw_init(&ip->i_lock, "ntnode");
        ntfs_ntget(ip);

        if (ntfs_nthashins(ip) != 0) {
                ntfs_ntput(ip);
                goto retry;
        }

        *ipp = ip;

        DPRINTF("ntfs_ntlookup: ntnode %u: %p, usecount: %d\n",
            ino, ip, ip->i_usecount);

        return (0);
}

/*
 * Decrement usecount of ntnode and unlock it, if usecount reach zero,
 * deallocate ntnode.
 *
 * ntnode should be locked on entry, and unlocked on return.
 */
void
ntfs_ntput(struct ntnode *ip)
{
        struct ntfsmount *ntmp = ip->i_mp;
        struct ntvattr *vap;

        DPRINTF("ntfs_ntput: rele ntnode %u: %p, usecount: %d\n",
            ip->i_number, ip, ip->i_usecount);

        ip->i_usecount--;

#ifdef DIAGNOSTIC
        if (ip->i_usecount < 0) {
                panic("ntfs_ntput: ino: %d usecount: %d ",
                      ip->i_number,ip->i_usecount);
        }
#endif

        if (ip->i_usecount > 0) {
                rw_exit_write(&ip->i_lock);
                return;
        }

        DPRINTF("ntfs_ntput: deallocating ntnode: %u\n", ip->i_number);

        if (LIST_FIRST(&ip->i_fnlist))
                panic("ntfs_ntput: ntnode has fnodes");

        ntfs_nthashrem(ip);

        /* Remove from loaded list. */
        if (ip->i_flag & IN_LOADED) {
                TAILQ_REMOVE(&ntmp->ntm_ntnodeq, ip, i_loaded);
                ntmp->ntm_ntnodes--;
        }

        while ((vap = LIST_FIRST(&ip->i_valist)) != NULL) {
                LIST_REMOVE(vap, va_list);
                ntfs_freentvattr(vap);
        }

        vrele(ip->i_devvp);
        free(ip, M_NTFSNTNODE, 0);
}

/*
 * increment usecount of ntnode 
 */
void
ntfs_ntref(struct ntnode *ip)
{
        ip->i_usecount++;

        DPRINTF("ntfs_ntref: ino %u, usecount: %d\n",
            ip->i_number, ip->i_usecount);
}

/*
 * Decrement usecount of ntnode.
 */
void
ntfs_ntrele(struct ntnode *ip)
{
        DPRINTF("ntfs_ntrele: rele ntnode %u: %p, usecount: %d\n",
            ip->i_number, ip, ip->i_usecount);

        ip->i_usecount--;

        if (ip->i_usecount < 0)
                panic("ntfs_ntrele: ino: %d usecount: %d ",
                      ip->i_number,ip->i_usecount);
}

/*
 * Deallocate all memory allocated for ntvattr
 */
void
ntfs_freentvattr(struct ntvattr *vap)
{
        if (vap->va_flag & NTFS_AF_INRUN) {
                if (vap->va_vruncn)
                        free(vap->va_vruncn, M_NTFSRUN, 0);
                if (vap->va_vruncl)
                        free(vap->va_vruncl, M_NTFSRUN, 0);
        } else {
                if (vap->va_datap)
                        free(vap->va_datap, M_NTFSRDATA, 0);
        }
        free(vap, M_NTFSNTVATTR, 0);
}

/*
 * Convert disk image of attribute into ntvattr structure,
 * runs are expanded also.
 */
int
ntfs_attrtontvattr(struct ntfsmount *ntmp, struct ntvattr **rvapp,
    struct attr *rap)
{
        int             error, i;
        struct ntvattr *vap;

        error = 0;
        *rvapp = NULL;

        vap = malloc(sizeof(*vap), M_NTFSNTVATTR, M_WAITOK | M_ZERO);
        vap->va_ip = NULL;
        vap->va_flag = rap->a_hdr.a_flag;
        vap->va_type = rap->a_hdr.a_type;
        vap->va_compression = rap->a_hdr.a_compression;
        vap->va_index = rap->a_hdr.a_index;

        DDPRINTF("type: 0x%x, index: %u", vap->va_type, vap->va_index);

        vap->va_namelen = rap->a_hdr.a_namelen;
        if (rap->a_hdr.a_namelen) {
                wchar *unp = (wchar *) ((caddr_t) rap + rap->a_hdr.a_nameoff);
                DDPRINTF(", name:[");
                for (i = 0; i < vap->va_namelen; i++) {
                        vap->va_name[i] = unp[i];
                        DDPRINTF("%c", vap->va_name[i]);
                }
                DDPRINTF("]");
        }
        if (vap->va_flag & NTFS_AF_INRUN) {
                DDPRINTF(", nonres.");
                vap->va_datalen = rap->a_nr.a_datalen;
                vap->va_allocated = rap->a_nr.a_allocated;
                vap->va_vcnstart = rap->a_nr.a_vcnstart;
                vap->va_vcnend = rap->a_nr.a_vcnend;
                vap->va_compressalg = rap->a_nr.a_compressalg;
                error = ntfs_runtovrun(&(vap->va_vruncn), &(vap->va_vruncl),
                                       &(vap->va_vruncnt),
                                       (caddr_t) rap + rap->a_nr.a_dataoff);
        } else {
                vap->va_compressalg = 0;
                DDPRINTF(", res.");
                vap->va_datalen = rap->a_r.a_datalen;
                vap->va_allocated = rap->a_r.a_datalen;
                vap->va_vcnstart = 0;
                vap->va_vcnend = ntfs_btocn(vap->va_allocated);
                vap->va_datap = malloc(vap->va_datalen, M_NTFSRDATA, M_WAITOK);
                memcpy(vap->va_datap, (caddr_t) rap + rap->a_r.a_dataoff,
                       rap->a_r.a_datalen);
        }
        DDPRINTF(", len: %llu", vap->va_datalen);

        if (error)
                free(vap, M_NTFSNTVATTR, 0);
        else
                *rvapp = vap;

        DDPRINTF("\n");

        return (error);
}

/*
 * Expand run into more utilizable and more memory eating format.
 */
int
ntfs_runtovrun(cn_t **rcnp, cn_t **rclp, u_long *rcntp, u_int8_t *run)
{
        u_int32_t       off;
        u_int32_t       sz, i;
        cn_t           *cn;
        cn_t           *cl;
        u_long          cnt;
        cn_t            prev;
        cn_t            tmp;

        off = 0;
        cnt = 0;
        while (run[off]) {
                off += (run[off] & 0xF) + ((run[off] >> 4) & 0xF) + 1;
                cnt++;
        }
        cn = mallocarray(cnt, sizeof(cn_t), M_NTFSRUN, M_WAITOK);
        cl = mallocarray(cnt, sizeof(cn_t), M_NTFSRUN, M_WAITOK);

        off = 0;
        cnt = 0;
        prev = 0;
        while (run[off]) {

                sz = run[off++];
                cl[cnt] = 0;

                for (i = 0; i < (sz & 0xF); i++)
                        cl[cnt] += (u_int32_t) run[off++] << (i << 3);

                sz >>= 4;
                if (run[off + sz - 1] & 0x80) {
                        tmp = ((u_int64_t) - 1) << (sz << 3);
                        for (i = 0; i < sz; i++)
                                tmp |= (u_int64_t) run[off++] << (i << 3);
                } else {
                        tmp = 0;
                        for (i = 0; i < sz; i++)
                                tmp |= (u_int64_t) run[off++] << (i << 3);
                }
                if (tmp)
                        prev = cn[cnt] = prev + tmp;
                else
                        cn[cnt] = tmp;

                cnt++;
        }
        *rcnp = cn;
        *rclp = cl;
        *rcntp = cnt;
        return (0);
}

/*
 * Compare unicode and ascii string case insens.
 */
int
ntfs_uastricmp(struct ntfsmount *ntmp, const wchar *ustr, size_t ustrlen,
    const char *astr, size_t astrlen)
{
        size_t  i;
        int             res;
        const char *astrend = astr + astrlen;

        for (i = 0; i < ustrlen && astr < astrend; i++) {
                res = (*ntmp->ntm_wcmp)(NTFS_TOUPPER(ustr[i]),
                                NTFS_TOUPPER((*ntmp->ntm_wget)(&astr)) );
                if (res)
                        return res;
        }

        if (i == ustrlen && astr == astrend)
                return 0;
        else if (i == ustrlen)
                return -1;
        else
                return 1;
}

/*
 * Compare unicode and ascii string case sens.
 */
int
ntfs_uastrcmp(struct ntfsmount *ntmp, const wchar *ustr, size_t ustrlen,
    const char *astr, size_t astrlen)
{
        size_t             i;
        int             res;
        const char *astrend = astr + astrlen;

        for (i = 0; (i < ustrlen) && (astr < astrend); i++) {
                res = (*ntmp->ntm_wcmp)(ustr[i], (*ntmp->ntm_wget)(&astr));
                if (res)
                        return res;
        }

        if (i == ustrlen && astr == astrend)
                return 0;
        else if (i == ustrlen)
                return -1;
        else
                return 1;
}

/* 
 * Search fnode in ntnode, if not found allocate and preinitialize.
 *
 * ntnode should be locked on entry.
 */
int
ntfs_fget(struct ntfsmount *ntmp, struct ntnode *ip, int attrtype,
    char *attrname, struct fnode **fpp)
{
        struct fnode *fp;

        DPRINTF("ntfs_fget: ino: %u, attrtype: 0x%x, attrname: %s\n",
            ip->i_number, attrtype, attrname ? attrname : "");
        *fpp = NULL;
        LIST_FOREACH(fp, &ip->i_fnlist, f_fnlist) {
                DPRINTF("ntfs_fget: fnode: attrtype: %u, attrname: %s\n",
                    fp->f_attrtype, fp->f_attrname ? fp->f_attrname : "");

                if ((attrtype == fp->f_attrtype) && 
                    ((!attrname && !fp->f_attrname) ||
                     (attrname && fp->f_attrname &&
                      !strcmp(attrname,fp->f_attrname)))){
                        DPRINTF("ntfs_fget: found existed: %p\n", fp);
                        *fpp = fp;
                }
        }

        if (*fpp)
                return (0);

        fp = malloc(sizeof(*fp), M_NTFSFNODE, M_WAITOK | M_ZERO);
        DPRINTF("ntfs_fget: allocating fnode: %p\n", fp);

        fp->f_ip = ip;
        fp->f_attrname = attrname;
        if (fp->f_attrname) fp->f_flag |= FN_AATTRNAME;
        fp->f_attrtype = attrtype;

        ntfs_ntref(ip);

        LIST_INSERT_HEAD(&ip->i_fnlist, fp, f_fnlist);

        *fpp = fp;

        return (0);
}

/*
 * Deallocate fnode, remove it from ntnode's fnode list.
 *
 * ntnode should be locked.
 */
void
ntfs_frele(struct fnode *fp)
{
        struct ntnode *ip = FTONT(fp);

        DPRINTF("ntfs_frele: fnode: %p for %u: %p\n", fp, ip->i_number, ip);

        DPRINTF("ntfs_frele: deallocating fnode\n");
        LIST_REMOVE(fp,f_fnlist);
        if (fp->f_flag & FN_AATTRNAME)
                free(fp->f_attrname, M_TEMP, 0);
        if (fp->f_dirblbuf)
                free(fp->f_dirblbuf, M_NTFSDIR, 0);
        free(fp, M_NTFSFNODE, 0);
        ntfs_ntrele(ip);
}

/*
 * Lookup attribute name in format: [[:$ATTR_TYPE]:$ATTR_NAME], 
 * $ATTR_TYPE is searched in attrdefs read from $AttrDefs.
 * If $ATTR_TYPE not specified, ATTR_A_DATA assumed.
 */
int
ntfs_ntlookupattr(struct ntfsmount *ntmp, const char *name, int namelen,
    int *attrtype, char **attrname)
{
        const char *sys;
        size_t syslen, i;
        struct ntvattrdef *adp;

        if (namelen == 0)
                return (0);

        if (name[0] == '$') {
                sys = name;
                for (syslen = 0; syslen < namelen; syslen++) {
                        if(sys[syslen] == ':') {
                                name++;
                                namelen--;
                                break;
                        }
                }
                name += syslen;
                namelen -= syslen;

                adp = ntmp->ntm_ad;
                for (i = 0; i < ntmp->ntm_adnum; i++, adp++){
                        if (syslen != adp->ad_namelen || 
                            strncmp(sys, adp->ad_name, syslen) != 0)
                                continue;

                        *attrtype = adp->ad_type;
                        goto out;
                }
                return (ENOENT);
        }

    out:
        if (namelen) {
                *attrname = malloc(namelen + 1, M_TEMP, M_WAITOK);
                memcpy(*attrname, name, namelen);
                (*attrname)[namelen] = '\0';
                *attrtype = NTFS_A_DATA;
        }

        return (0);
}

/*
 * Lookup specified node for filename, matching cnp, return fnode filled.
 */
int
ntfs_ntlookupfile(struct ntfsmount *ntmp, struct vnode *vp,
    struct componentname *cnp, struct vnode **vpp)
{
        struct fnode   *fp = VTOF(vp);
        struct ntnode  *ip = FTONT(fp);
        struct ntvattr *vap = NULL;     /* Root attribute */
        cn_t            cn = 0; /* VCN in current attribute */
        caddr_t         rdbuf = NULL;   /* Buffer to read directory's blocks */
        u_int32_t       blsize;
        u_int32_t       rdsize; /* Length of data to read from current block */
        struct attr_indexentry *iep;
        int             error, res, anamelen, fnamelen;
        const char     *fname,*aname;
        u_int32_t       aoff;
        int attrtype = NTFS_A_DATA;
        char *attrname = NULL;
        struct fnode   *nfp;
        struct vnode   *nvp;
        enum vtype      f_type;
        int fullscan = 0;
        struct ntfs_lookup_ctx *lookup_ctx = NULL, *tctx;

        error = ntfs_ntget(ip);
        if (error)
                return (error);

        error = ntfs_ntvattrget(ntmp, ip, NTFS_A_INDXROOT, "$I30", 0, &vap);
        if (error || (vap->va_flag & NTFS_AF_INRUN)) {
                error = ENOTDIR;
                goto fail;
        }

        /*
         * Divide file name into: foofilefoofilefoofile[:attrspec]
         * Store like this:       fname:fnamelen       [aname:anamelen]
         */
        fname = cnp->cn_nameptr;
        aname = NULL;
        anamelen = 0;
        for (fnamelen = 0; fnamelen < cnp->cn_namelen; fnamelen++)
                if(fname[fnamelen] == ':') {
                        aname = fname + fnamelen + 1;
                        anamelen = cnp->cn_namelen - fnamelen - 1;
                        DPRINTF("ntfs_ntlookupfile: %s (%d), attr: %s (%d)\n",
                            fname, fnamelen, aname, anamelen);
                        break;
                }

        blsize = vap->va_a_iroot->ir_size;
        DPRINTF("ntfs_ntlookupfile: blksz: %u\n", blsize);

        rdbuf = malloc(blsize, M_TEMP, M_WAITOK);

    loop:
        rdsize = vap->va_datalen;
        DPRINTF("ntfs_ntlookupfile: rdsz: %u\n", rdsize);

        error = ntfs_readattr(ntmp, ip, NTFS_A_INDXROOT, "$I30",
                               0, rdsize, rdbuf, NULL);
        if (error)
                goto fail;

        aoff = sizeof(struct attr_indexroot);

        do {
                iep = (struct attr_indexentry *) (rdbuf + aoff);

                for (; !(iep->ie_flag & NTFS_IEFLAG_LAST) && (rdsize > aoff);
                        aoff += iep->reclen,
                        iep = (struct attr_indexentry *) (rdbuf + aoff))
                {
                        DDPRINTF("scan: %u, %u\n", iep->ie_number,
                            iep->ie_fnametype);
 
                        /* check the name - the case-insensitive check
                         * has to come first, to break from this for loop
                         * if needed, so we can dive correctly */
                        res = ntfs_uastricmp(ntmp, iep->ie_fname,
                                iep->ie_fnamelen, fname, fnamelen);
                        if (!fullscan) {
                                if (res > 0) break;
                                if (res < 0) continue;
                        }

                        if (iep->ie_fnametype == 0 ||
                            !(ntmp->ntm_flag & NTFS_MFLAG_CASEINS))
                        {
                                res = ntfs_uastrcmp(ntmp, iep->ie_fname,
                                        iep->ie_fnamelen, fname, fnamelen);
                                if (res != 0 && !fullscan) continue;
                        }

                        /* if we perform full scan, the file does not match
                         * and this is subnode, dive */
                        if (fullscan && res != 0) {
                            if (iep->ie_flag & NTFS_IEFLAG_SUBNODE) {
                                tctx = malloc(sizeof(struct ntfs_lookup_ctx),
                                        M_TEMP, M_WAITOK);
                                tctx->aoff      = aoff + iep->reclen;
                                tctx->rdsize    = rdsize;
                                tctx->cn        = cn;
                                tctx->prev      = lookup_ctx;
                                lookup_ctx = tctx;
                                break;
                            } else
                                continue;
                        }

                        if (aname) {
                                error = ntfs_ntlookupattr(ntmp,
                                        aname, anamelen,
                                        &attrtype, &attrname);
                                if (error)
                                        goto fail;
                        }

                        /* Check if we've found ourselves */
                        if ((iep->ie_number == ip->i_number) &&
                            (attrtype == fp->f_attrtype) &&
                            ((!attrname && !fp->f_attrname) ||
                             (attrname && fp->f_attrname &&
                              !strcmp(attrname, fp->f_attrname))))
                        {
                                vref(vp);
                                *vpp = vp;
                                error = 0;
                                goto fail;
                        }

                        /* free the buffer returned by ntfs_ntlookupattr() */
                        if (attrname) {
                                free(attrname, M_TEMP, 0);
                                attrname = NULL;
                        }

                        /* vget node, but don't load it */
                        error = ntfs_vgetex(ntmp->ntm_mountp,
                                   iep->ie_number, attrtype, attrname,
                                   LK_EXCLUSIVE, VG_DONTLOADIN | VG_DONTVALIDFN,
                                   &nvp);
                        if (error)
                                goto fail;

                        nfp = VTOF(nvp);

                        if (nfp->f_flag & FN_VALID) {
                                *vpp = nvp;
                                goto fail;
                        }

                        nfp->f_fflag = iep->ie_fflag;
                        nfp->f_pnumber = iep->ie_fpnumber;
                        nfp->f_times = iep->ie_ftimes;

                        if((nfp->f_fflag & NTFS_FFLAG_DIR) &&
                           (nfp->f_attrtype == NTFS_A_DATA) &&
                           (nfp->f_attrname == NULL))
                                f_type = VDIR;  
                        else
                                f_type = VREG;  

                        nvp->v_type = f_type;

                        if ((nfp->f_attrtype == NTFS_A_DATA) &&
                            (nfp->f_attrname == NULL))
                        {
                                /* Opening default attribute */
                                nfp->f_size = iep->ie_fsize;
                                nfp->f_allocated = iep->ie_fallocated;
                                nfp->f_flag |= FN_PRELOADED;
                        } else {
                                error = ntfs_filesize(ntmp, nfp,
                                            &nfp->f_size, &nfp->f_allocated);
                                if (error) {
                                        vput(nvp);
                                        goto fail;
                                }
                        }

                        nfp->f_flag &= ~FN_VALID;
                        *vpp = nvp;
                        goto fail;
                }

                /* Dive if possible */
                if (iep->ie_flag & NTFS_IEFLAG_SUBNODE) {
                        DPRINTF("ntfs_ntlookupfile: diving\n");

                        cn = *(cn_t *) (rdbuf + aoff +
                                        iep->reclen - sizeof(cn_t));
                        rdsize = blsize;

                        error = ntfs_readattr(ntmp, ip, NTFS_A_INDX, "$I30",
                                        ntfs_cntob(cn), rdsize, rdbuf, NULL);
                        if (error)
                                goto fail;

                        error = ntfs_procfixups(ntmp, NTFS_INDXMAGIC,
                                                rdbuf, rdsize);
                        if (error)
                                goto fail;

                        aoff = (((struct attr_indexalloc *) rdbuf)->ia_hdrsize +
                                0x18);
                } else if (fullscan && lookup_ctx) {
                        cn = lookup_ctx->cn;
                        aoff = lookup_ctx->aoff;
                        rdsize = lookup_ctx->rdsize;

                        error = ntfs_readattr(ntmp, ip,
                                (cn == 0) ? NTFS_A_INDXROOT : NTFS_A_INDX,
                                "$I30", ntfs_cntob(cn), rdsize, rdbuf, NULL);
                        if (error)
                                goto fail;
                        
                        if (cn != 0) {
                                error = ntfs_procfixups(ntmp, NTFS_INDXMAGIC,
                                                rdbuf, rdsize);
                                if (error)
                                        goto fail;
                        }

                        tctx = lookup_ctx;
                        lookup_ctx = lookup_ctx->prev;
                        free(tctx, M_TEMP, 0);
                } else {
                        DPRINTF("ntfs_ntlookupfile: nowhere to dive :-(\n");
                        error = ENOENT;
                        break;
                }
        } while (1);

        if (error == ENOENT) {
                /* perform full scan if no entry was found */
                if (!fullscan) {
                        fullscan = 1;
                        cn = 0;         /* need zero, used by lookup_ctx */

                        DDPRINTF("ntfs_ntlookupfile: fullscan performed for: %.*s\n",
                            (unsigned int)fnamelen, fname);
                        goto loop;
                }

                if ((cnp->cn_flags & ISLASTCN) &&
                    (cnp->cn_nameiop == CREATE || cnp->cn_nameiop == RENAME))
                        error = EJUSTRETURN;
        }

        DPRINTF("finish\n");

fail:
        if (vap)
                ntfs_ntvattrrele(vap);
        if (rdbuf)
                free(rdbuf, M_TEMP, 0);
        if (attrname)
                free(attrname, M_TEMP, 0);
        if (lookup_ctx) {
                while(lookup_ctx) {
                        tctx = lookup_ctx;
                        lookup_ctx = lookup_ctx->prev;
                        free(tctx, M_TEMP, 0);
                }
        }
        ntfs_ntput(ip);
        return (error);
}

/*
 * Check if name type is permitted to show.
 */
int
ntfs_isnamepermitted(struct ntfsmount *ntmp, struct attr_indexentry *iep)
{
        if (ntmp->ntm_flag & NTFS_MFLAG_ALLNAMES)
                return 1;

        switch (iep->ie_fnametype) {
        case 2:
                DDPRINTF("ntfs_isnamepermitted: skipped DOS name\n");
                return 0;
        case 0: case 1: case 3:
                return 1;
        default:
                printf("ntfs_isnamepermitted: " \
                       "WARNING! Unknown file name type: %d\n",
                       iep->ie_fnametype);
                break;
        }
        return 0;
}

/*
 * Read ntfs dir like stream of attr_indexentry, not like btree of them.
 * This is done by scanning $BITMAP:$I30 for busy clusters and reading them.
 * Of course $INDEX_ROOT:$I30 is read before. Last read values are stored in
 * fnode, so we can skip toward record number num almost immediately.
 * Anyway this is rather slow routine. The problem is that we don't know
 * how many records are there in $INDEX_ALLOCATION:$I30 block.
 */
int
ntfs_ntreaddir(struct ntfsmount *ntmp, struct fnode *fp, u_int32_t num,
    struct attr_indexentry **riepp, struct proc *p)
{
        struct ntnode  *ip = FTONT(fp);
        struct ntvattr *vap = NULL;     /* IndexRoot attribute */
        struct ntvattr *bmvap = NULL;   /* BitMap attribute */
        struct ntvattr *iavap = NULL;   /* IndexAllocation attribute */
        caddr_t         rdbuf;          /* Buffer to read directory's blocks  */
        u_int8_t       *bmp = NULL;     /* Bitmap */
        u_int32_t       blsize;         /* Index allocation size (2048) */
        u_int32_t       rdsize;         /* Length of data to read */
        u_int32_t       attrnum;        /* Current attribute type */
        u_int32_t       cpbl = 1;       /* Clusters per directory block */
        u_int32_t       blnum;
        struct attr_indexentry *iep;
        int             error = ENOENT;
        u_int32_t       aoff, cnum;

        DPRINTF("ntfs_ntreaddir: read ino: %u, num: %u\n", ip->i_number, num);
        error = ntfs_ntget(ip);
        if (error)
                return (error);

        error = ntfs_ntvattrget(ntmp, ip, NTFS_A_INDXROOT, "$I30", 0, &vap);
        if (error) {
                error = ENOTDIR;
                goto fail;
        }

        if (fp->f_dirblbuf == NULL) {
                fp->f_dirblsz = vap->va_a_iroot->ir_size;
                fp->f_dirblbuf = malloc(MAX(vap->va_datalen,fp->f_dirblsz),
                    M_NTFSDIR, M_WAITOK);
        }

        blsize = fp->f_dirblsz;
        rdbuf = fp->f_dirblbuf;

        DPRINTF("ntfs_ntreaddir: rdbuf: %p, blsize: %u\n", rdbuf, blsize);

        if (vap->va_a_iroot->ir_flag & NTFS_IRFLAG_INDXALLOC) {
                error = ntfs_ntvattrget(ntmp, ip, NTFS_A_INDXBITMAP, "$I30",
                                        0, &bmvap);
                if (error) {
                        error = ENOTDIR;
                        goto fail;
                }
                bmp = malloc(bmvap->va_datalen, M_TEMP, M_WAITOK);
                error = ntfs_readattr(ntmp, ip, NTFS_A_INDXBITMAP, "$I30", 0,
                                       bmvap->va_datalen, bmp, NULL);
                if (error)
                        goto fail;

                error = ntfs_ntvattrget(ntmp, ip, NTFS_A_INDX, "$I30",
                                        0, &iavap);
                if (error) {
                        error = ENOTDIR;
                        goto fail;
                }
                cpbl = ntfs_btocn(blsize + ntfs_cntob(1) - 1);
                DPRINTF("ntfs_ntreaddir: indexalloc: %llu, cpbl: %u\n",
                    iavap->va_datalen, cpbl);
        } else {
                DPRINTF("ntfs_ntreadidir: w/o BitMap and IndexAllocation\n");
                iavap = bmvap = NULL;
                bmp = NULL;
        }

        /* Try use previous values */
        if ((fp->f_lastdnum < num) && (fp->f_lastdnum != 0)) {
                attrnum = fp->f_lastdattr;
                aoff = fp->f_lastdoff;
                blnum = fp->f_lastdblnum;
                cnum = fp->f_lastdnum;
        } else {
                attrnum = NTFS_A_INDXROOT;
                aoff = sizeof(struct attr_indexroot);
                blnum = 0;
                cnum = 0;
        }

        do {
                DPRINTF("ntfs_ntreaddir: scan: 0x%x, %u, %u, %u, %u\n",
                    attrnum, blnum, cnum, num, aoff);
                rdsize = (attrnum == NTFS_A_INDXROOT) ? vap->va_datalen : blsize;
                error = ntfs_readattr(ntmp, ip, attrnum, "$I30",
                                ntfs_cntob(blnum * cpbl), rdsize, rdbuf, NULL);
                if (error)
                        goto fail;

                if (attrnum == NTFS_A_INDX) {
                        error = ntfs_procfixups(ntmp, NTFS_INDXMAGIC,
                                                rdbuf, rdsize);
                        if (error)
                                goto fail;
                }
                if (aoff == 0)
                        aoff = (attrnum == NTFS_A_INDX) ?
                                (0x18 + ((struct attr_indexalloc *) rdbuf)->ia_hdrsize) :
                                sizeof(struct attr_indexroot);

                iep = (struct attr_indexentry *) (rdbuf + aoff);
                for (; !(iep->ie_flag & NTFS_IEFLAG_LAST) && (rdsize > aoff);
                        aoff += iep->reclen,
                        iep = (struct attr_indexentry *) (rdbuf + aoff))
                {
                        if (!ntfs_isnamepermitted(ntmp, iep)) continue;

                        if (cnum >= num) {
                                fp->f_lastdnum = cnum;
                                fp->f_lastdoff = aoff;
                                fp->f_lastdblnum = blnum;
                                fp->f_lastdattr = attrnum;

                                *riepp = iep;

                                error = 0;
                                goto fail;
                        }
                        cnum++;
                }

                if (iavap) {
                        if (attrnum == NTFS_A_INDXROOT)
                                blnum = 0;
                        else
                                blnum++;

                        while (ntfs_cntob(blnum * cpbl) < iavap->va_datalen) {
                                if (bmp[blnum >> 3] & (1 << (blnum & 7)))
                                        break;
                                blnum++;
                        }

                        attrnum = NTFS_A_INDX;
                        aoff = 0;
                        if (ntfs_cntob(blnum * cpbl) >= iavap->va_datalen)
                                break;
                        DPRINTF("ntfs_ntreaddir: blnum: %u\n", blnum);
                }
        } while (iavap);

        *riepp = NULL;
        fp->f_lastdnum = 0;

fail:
        if (vap)
                ntfs_ntvattrrele(vap);
        if (bmvap)
                ntfs_ntvattrrele(bmvap);
        if (iavap)
                ntfs_ntvattrrele(iavap);
        if (bmp)
                free(bmp, M_TEMP, 0);
        ntfs_ntput(ip);

        return (error);
}

/*
 * Convert NTFS times that are in 100 ns units and begins from
 * 1601 Jan 1 into unix times.
 */
struct timespec
ntfs_nttimetounix(u_int64_t nt)
{
        struct timespec t;

        /* Windows NT times are in 100 ns and from 1601 Jan 1 */
        t.tv_nsec = (nt % (1000 * 1000 * 10)) * 100;
        t.tv_sec = nt / (1000 * 1000 * 10) -
                369LL * 365LL * 24LL * 60LL * 60LL -
                89LL * 1LL * 24LL * 60LL * 60LL;
        return (t);
}

/*
 * Get file sizes from corresponding attribute. 
 * 
 * ntnode under fnode should be locked.
 */
int
ntfs_filesize(struct ntfsmount *ntmp, struct fnode *fp, u_int64_t *size,
    u_int64_t *bytes)
{
        struct ntvattr *vap;
        struct ntnode *ip = FTONT(fp);
        u_int64_t       sz, bn;
        int             error;

        DPRINTF("ntfs_filesize: ino: %u\n", ip->i_number);

        error = ntfs_ntvattrget(ntmp, ip,
                fp->f_attrtype, fp->f_attrname, 0, &vap);
        if (error)
                return (error);

        bn = vap->va_allocated;
        sz = vap->va_datalen;

        DPRINTF("ntfs_filesize: %llu bytes (%llu bytes allocated)\n", sz, bn);

        if (size)
                *size = sz;
        if (bytes)
                *bytes = bn;

        ntfs_ntvattrrele(vap);

        return (0);
}

/*
 * This is one of the read routines.
 *
 * ntnode should be locked.
 */
int
ntfs_readntvattr_plain(struct ntfsmount *ntmp, struct ntnode *ip,
    struct ntvattr *vap, off_t roff, size_t rsize, void *rdata, size_t *initp,
    struct uio *uio)
{
        int             error = 0;
        off_t           off;

        *initp = 0;
        if (vap->va_flag & NTFS_AF_INRUN) {
                int             cnt;
                cn_t            ccn, ccl, cn, cl;
                caddr_t         data = rdata;
                struct buf     *bp;
                size_t          left, tocopy;

                DDPRINTF("ntfs_readntvattr_plain: data in run: %lu chains\n",
                    vap->va_vruncnt);

                off = roff;
                left = rsize;
                ccl = 0;
                ccn = 0;
                cnt = 0;
                while (left && (cnt < vap->va_vruncnt)) {
                        ccn = vap->va_vruncn[cnt];
                        ccl = vap->va_vruncl[cnt];

                        DDPRINTF("ntfs_readntvattr_plain: left %zu, "
                            "cn: 0x%llx, cl: %llu, off: %lld\n",
                            left, ccn, ccl, off);

                        if (ntfs_cntob(ccl) < off) {
                                off -= ntfs_cntob(ccl);
                                cnt++;
                                continue;
                        }
                        if (ccn || ip->i_number == NTFS_BOOTINO) {
                                ccl -= ntfs_btocn(off);
                                cn = ccn + ntfs_btocn(off);
                                off = ntfs_btocnoff(off);

                                while (left && ccl) {
                                        /*
                                         * Always read single clusters at a
                                         * time - we need to avoid reading
                                         * differently-sized blocks at the
                                         * same disk offsets to avoid
                                         * confusing the buffer cache.
                                         */
                                        tocopy = MIN(left,
                                            ntfs_cntob(1) - off);
                                        cl = ntfs_btocl(tocopy + off);
                                        KASSERT(cl == 1 &&
                                            tocopy <= ntfs_cntob(1));

                                        DDPRINTF("ntfs_readntvattr_plain: "
                                            "read: cn: 0x%llx cl: %llu, "
                                            "off: %lld, len: %zu, "
                                            "left: %zu\n",
                                            cn, cl, off, tocopy, left);
                                        error = bread(ntmp->ntm_devvp,
                                                      ntfs_cntobn(cn),
                                                      ntfs_cntob(cl),
                                                      &bp);
                                        if (error) {
                                                brelse(bp);
                                                return (error);
                                        }
                                        if (uio) {
                                                error = uiomove(bp->b_data + off,
                                                        tocopy, uio);
                                                if (error != 0)
                                                        break;
                                        } else {
                                                memcpy(data, bp->b_data + off,
                                                        tocopy);
                                        }
                                        brelse(bp);
                                        data = data + tocopy;
                                        *initp += tocopy;
                                        off = 0;
                                        left -= tocopy;
                                        cn += cl;
                                        ccl -= cl;
                                }
                        } else {
                                tocopy = MIN(left, ntfs_cntob(ccl) - off);
                                DDPRINTF("ntfs_readntvattr_plain: hole: "
                                    "ccn: 0x%llx ccl: %llu, off: %lld, "
                                    "len: %zu, left: %zu\n",
                                    ccn, ccl, off, tocopy, left);
                                left -= tocopy;
                                off = 0;
                                if (uio) {
                                        size_t remains = tocopy;
                                        for(; remains; remains--) {
                                                error = uiomove("", 1, uio);
                                                if (error != 0)
                                                        break;
                                        }
                                } else 
                                        bzero(data, tocopy);
                                data = data + tocopy;
                        }
                        cnt++;
                        if (error != 0)
                                break;
                }
                if (left && error == 0) {
                        printf("ntfs_readntvattr_plain: POSSIBLE RUN ERROR\n");
                        error = E2BIG;
                }
        } else {
                DDPRINTF("ntfs_readnvattr_plain: data is in mft record\n");
                if (uio) 
                        error = uiomove(vap->va_datap + roff, rsize, uio);
                else
                        memcpy(rdata, vap->va_datap + roff, rsize);
                *initp += rsize;
        }

        return (error);
}

/*
 * This is one of read routines.
 */
int
ntfs_readattr_plain(struct ntfsmount *ntmp, struct ntnode *ip,
    u_int32_t attrnum, char *attrname, off_t roff, size_t rsize, void *rdata,
    size_t *initp, struct uio *uio)
{
        size_t          init;
        int             error = 0;
        off_t           off = roff;
        size_t          left = rsize, toread;
        caddr_t         data = rdata;
        struct ntvattr *vap;
        *initp = 0;

        while (left) {
                error = ntfs_ntvattrget(ntmp, ip, attrnum, attrname,
                                        ntfs_btocn(off), &vap);
                if (error)
                        return (error);
                toread = MIN(left, ntfs_cntob(vap->va_vcnend + 1) - off);
                DDPRINTF("ntfs_readattr_plain: o: %lld, s: %zu "
                    "(%llu - %llu)\n", off, toread,
                    vap->va_vcnstart, vap->va_vcnend);
                error = ntfs_readntvattr_plain(ntmp, ip, vap,
                                         off - ntfs_cntob(vap->va_vcnstart),
                                         toread, data, &init, uio);
                if (error) {
                        printf("ntfs_readattr_plain: ntfs_readntvattr_plain "
                            "failed: o: %lld, s: %zu\n", off, toread);
                        printf("ntfs_readattr_plain: attrib: %llu - %llu\n",
                               vap->va_vcnstart, vap->va_vcnend);
                        ntfs_ntvattrrele(vap);
                        break;
                }
                ntfs_ntvattrrele(vap);
                left -= toread;
                off += toread;
                data = data + toread;
                *initp += init;
        }

        return (error);
}

/*
 * This is one of read routines.
 */
int
ntfs_readattr(struct ntfsmount *ntmp, struct ntnode *ip, u_int32_t attrnum,
    char *attrname, off_t roff, size_t rsize, void *rdata, struct uio *uio)
{
        int             error = 0;
        struct ntvattr *vap;
        size_t          init;

        DDPRINTF("ntfs_readattr: reading %u: 0x%x, from %lld size %zu bytes\n",
            ip->i_number, attrnum, roff, rsize);

        error = ntfs_ntvattrget(ntmp, ip, attrnum, attrname, 0, &vap);
        if (error)
                return (error);

        if ((roff > vap->va_datalen) ||
            (roff + rsize > vap->va_datalen)) {
                printf("ntfs_readattr: offset too big: %lld (%lld) > %llu\n",
                    roff, roff + rsize, vap->va_datalen);
                ntfs_ntvattrrele(vap);
                return (E2BIG);
        }
        if (vap->va_compression && vap->va_compressalg) {
                u_int8_t       *cup;
                u_int8_t       *uup;
                off_t           off = roff;
                caddr_t         data = rdata;
                cn_t            cn;
                size_t          left = rsize, tocopy;

                DDPRINTF("ntfs_ntreadattr: compression: %u\n",
                    vap->va_compressalg);

                cup = malloc(ntfs_cntob(NTFS_COMPUNIT_CL), M_NTFSDECOMP,
                    M_WAITOK);
                uup = malloc(ntfs_cntob(NTFS_COMPUNIT_CL), M_NTFSDECOMP,
                    M_WAITOK);

                cn = (ntfs_btocn(roff)) & (~(NTFS_COMPUNIT_CL - 1));
                off = roff - ntfs_cntob(cn);

                while (left) {
                        error = ntfs_readattr_plain(ntmp, ip, attrnum,
                                                  attrname, ntfs_cntob(cn),
                                                  ntfs_cntob(NTFS_COMPUNIT_CL),
                                                  cup, &init, NULL);
                        if (error)
                                break;

                        tocopy = MIN(left, ntfs_cntob(NTFS_COMPUNIT_CL) - off);

                        if (init == ntfs_cntob(NTFS_COMPUNIT_CL)) {
                                if (uio)
                                        error = uiomove(cup + off, tocopy, uio);
                                else
                                        memcpy(data, cup + off, tocopy);
                        } else if (init == 0) {
                                if (uio) {
                                        size_t remains = tocopy;
                                        for(; remains; remains--) {
                                                error = uiomove("", 1, uio);
                                                if (error != 0)
                                                        break;
                                        }
                                }
                                else
                                        bzero(data, tocopy);
                        } else {
                                error = ntfs_uncompunit(ntmp, uup, cup);
                                if (error)
                                        break;
                                if (uio)
                                        error = uiomove(uup + off, tocopy, uio);
                                else
                                        memcpy(data, uup + off, tocopy);
                        }
                        if (error)
                                break;

                        left -= tocopy;
                        data = data + tocopy;
                        off += tocopy - ntfs_cntob(NTFS_COMPUNIT_CL);
                        cn += NTFS_COMPUNIT_CL;
                }

                free(uup, M_NTFSDECOMP, 0);
                free(cup, M_NTFSDECOMP, 0);
        } else
                error = ntfs_readattr_plain(ntmp, ip, attrnum, attrname,
                                             roff, rsize, rdata, &init, uio);
        ntfs_ntvattrrele(vap);
        return (error);
}

#if UNUSED_CODE
int
ntfs_parserun(cn_t *cn, cn_t *cl, u_int8_t *run, u_long len, u_long *off)
{
        u_int8_t        sz;
        int             i;

        if (NULL == run) {
                printf("ntfs_parsetun: run == NULL\n");
                return (EINVAL);
        }
        sz = run[(*off)++];
        if (0 == sz) {
                printf("ntfs_parserun: trying to go out of run\n");
                return (E2BIG);
        }
        *cl = 0;
        if ((sz & 0xF) > 8 || (*off) + (sz & 0xF) > len) {
                printf("ntfs_parserun: " \
                       "bad run: length too big: sz: 0x%02x (%ld < %ld + sz)\n",
                       sz, len, *off);
                return (EINVAL);
        }
        for (i = 0; i < (sz & 0xF); i++)
                *cl += (u_int32_t) run[(*off)++] << (i << 3);

        sz >>= 4;
        if ((sz & 0xF) > 8 || (*off) + (sz & 0xF) > len) {
                printf("ntfs_parserun: " \
                       "bad run: length too big: sz: 0x%02x (%ld < %ld + sz)\n",
                       sz, len, *off);
                return (EINVAL);
        }
        for (i = 0; i < (sz & 0xF); i++)
                *cn += (u_int32_t) run[(*off)++] << (i << 3);

        return (0);
}
#endif

/*
 * Process fixup routine on given buffer.
 */
int
ntfs_procfixups(struct ntfsmount *ntmp, u_int32_t magic, caddr_t buf,
    size_t len)
{
        struct fixuphdr *fhp = (struct fixuphdr *) buf;
        int             i;
        u_int16_t       fixup;
        u_int16_t      *fxp;
        u_int16_t      *cfxp;

        if (fhp->fh_magic != magic) {
                printf("ntfs_procfixups: magic doesn't match: %08x != %08x\n",
                       fhp->fh_magic, magic);
                return (EINVAL);
        }
        if ((fhp->fh_fnum - 1) * ntmp->ntm_bps != len) {
                printf("ntfs_procfixups: " \
                       "bad fixups number: %d for %ld bytes block\n", 
                       fhp->fh_fnum, (long)len);        /* XXX printf kludge */
                return (EINVAL);
        }
        if (fhp->fh_foff >= ntmp->ntm_spc * ntmp->ntm_mftrecsz * ntmp->ntm_bps) {
                printf("ntfs_procfixups: invalid offset: %x", fhp->fh_foff);
                return (EINVAL);
        }
        fxp = (u_int16_t *) (buf + fhp->fh_foff);
        cfxp = (u_int16_t *) (buf + ntmp->ntm_bps - 2);
        fixup = *fxp++;
        for (i = 1; i < fhp->fh_fnum; i++, fxp++) {
                if (*cfxp != fixup) {
                        printf("ntfs_procfixups: fixup %d doesn't match\n", i);
                        return (EINVAL);
                }
                *cfxp = *fxp;
                cfxp = (u_int16_t *)((caddr_t)cfxp + ntmp->ntm_bps);
        }
        return (0);
}

#if UNUSED_CODE
int
ntfs_runtocn(cn_t *cn, struct ntfsmount *ntmp, u_int8_t *run, u_long len,
    cn_t vcn)
{
        cn_t            ccn = 0;
        cn_t            ccl = 0;
        u_long          off = 0;
        int             error = 0;

#if NTFS_DEBUG
        int             i;
        printf("ntfs_runtocn: run: %p, %ld bytes, vcn:%ld\n",
                run, len, (u_long) vcn);
        printf("ntfs_runtocn: run: ");
        for (i = 0; i < len; i++)
                printf("0x%02x ", run[i]);
        printf("\n");
#endif

        if (NULL == run) {
                printf("ntfs_runtocn: run == NULL\n");
                return (EINVAL);
        }
        do {
                if (run[off] == 0) {
                        printf("ntfs_runtocn: vcn too big\n");
                        return (E2BIG);
                }
                vcn -= ccl;
                error = ntfs_parserun(&ccn, &ccl, run, len, &off);
                if (error) {
                        printf("ntfs_runtocn: ntfs_parserun failed\n");
                        return (error);
                }
        } while (ccl <= vcn);
        *cn = ccn + vcn;
        return (0);
}
#endif

/*
 * if the ntfs_toupper_tab[] is filled already, just raise use count;
 * otherwise read the data from the filesystem we are currently mounting
 */
int
ntfs_toupper_use(struct mount *mp, struct ntfsmount *ntmp, struct proc *p)
{
        int error = 0;
        struct vnode *vp;

        /* get exclusive access */
        rw_enter_write(&ntfs_toupper_lock);

        /* only read the translation data from a file if it hasn't been
         * read already */
        if (ntfs_toupper_tab)
                goto out;

        /*
         * Read in Unicode lowercase -> uppercase translation file.
         * XXX for now, just the first 256 entries are used anyway,
         * so don't bother reading more
         */
        ntfs_toupper_tab = malloc(256 * 256 * sizeof(wchar), M_NTFSRDATA,
            M_WAITOK);

        if ((error = VFS_VGET(mp, NTFS_UPCASEINO, &vp)))
                goto out;
        error = ntfs_readattr(ntmp, VTONT(vp), NTFS_A_DATA, NULL,
                        0, 256*256*sizeof(wchar), (char *) ntfs_toupper_tab,
                        NULL);
        vput(vp);

    out:
        ntfs_toupper_usecount++;
        rw_exit_write(&ntfs_toupper_lock);
        return (error);
}

/*
 * lower the use count and if it reaches zero, free the memory
 * tied by toupper table
 */
void
ntfs_toupper_unuse(struct proc *p)
{
        /* get exclusive access */
        rw_enter_write(&ntfs_toupper_lock);

        ntfs_toupper_usecount--;
        if (ntfs_toupper_usecount == 0) {
                free(ntfs_toupper_tab, M_NTFSRDATA, 0);
                ntfs_toupper_tab = NULL;
        }
#ifdef DIAGNOSTIC
        else if (ntfs_toupper_usecount < 0) {
                panic("ntfs_toupper_unuse(): use count negative: %d",
                        ntfs_toupper_usecount);
        }
#endif
        
        /* release the lock */
        rw_exit_write(&ntfs_toupper_lock);
}